CHANNAI, India (Reuters Health) Dec 28 - Yoga induces a feeling of well-being in healthy people, and can reverse the clinical and biochemical changes associated with metabolic syndrome, according to results of studies from Sweden and India.
Dr. R.P. Agrawal, of the SP Medical College, Bikaner, India, and colleagues evaluated the beneficial effects of yoga and meditation in 101 adults with features of metabolic syndrome. In their randomized study, 55 subjects were assigned to 3 months of regular daily yoga, including standard postures, and Raja Yoga, a form of transcendental meditation, while the remaining received standard care.
Waist circumference, systolic blood pressure, fasting blood sugar, and triglycerides were significantly lower, and high density lipoprotein levels were higher in the yoga group as compared to controls, Dr. Agrawal's team reports in the December issue of Diabetes Research and Clinical Practice.
"Yoga and meditation have always been an essential part of life in the traditional system of treatment," Dr. R.P Agrawal and colleagues write. They attribute the effects to the redistribution of body fat, decreased arterial tone and peripheral resistance due to parasympathetic predominance, and increased sensitivity of beta cells of the pancreas.
In the second report, published on December 19 in BioMed Central Complementary and Alternative Medicine, Dr. Anette Kjellgren from the University of Karlstad, Sweden and her team evaluated the beneficial effects of yogic breathing exercises on healthy volunteers.
Fifty-five adults were advised to practice "Sudarshan Kriya," which involves cycles of slow normal and rapid breathing exercises. The exercises were practiced for an hour daily, six days a week for six weeks, while 48 controls were advised to relax in an armchair for 15 minutes daily.
At the end of the study period, feelings of anxiety, stress and depression were significantly decreased, and optimism was significantly increased, in the yoga group compared to controls, Dr. Kjellgren and colleagues report.
Yoga induces a "relaxation response" associated with reduced sympathetic nervous system activity and a feeling of well-being probably due to an increase in antioxidants and lower levels of cortisol, Dr. Kjellgren's team suggests.
Yoga not only helps in prevention of lifestyle diseases, but can also be "a powerful adjunct therapy when these diseases arise," co-author Dr. Faahri Saatiglou, from the University of Oslo, told Reuters Health. "We do not emphasize this point enough in our Western health care."
Sunday, December 30, 2007
New Findings About Dangerous Cancer Protein
new report from the University of Pennsylvania and Johns Hopkins University finds the Myc protein can stop the production of at least 13 microsRNAs – small pieces of nucleic acid that help control which genes are turned on and off.
The study also finds in several cases, re-introducing repressed miRNAs into Myc-containing cancer cells suppressed tumor growth in mice – this means it is possible that a gene-therapy approach could be effective in treating some cancers.
Researchers analyzed more than 300 miRNAs in lymphoma cells of humans and mice. They had previously found Myc could turn on one particular group of growth-promoting miRNAs in lymphoma cells. In the cells with high amounts of Myc protein, researchers found big changes in the quantities of at least 13 miRNAs.
When researchers took a closer look at the DNA of the lymphoma cells, they found Myc was directly attaching to the DNA at the miRNA genes.
“This study expands our understanding of how Myc acts as such a potent cancer-promoting protein,” lead researcher Joshua Mendell, Johns Hopkins University, was quoted as saying. “We already knew that it can directly regulate thousands of genes. Through its repertoire of miRNAs, Myc likely influences the expression of thousands of additional genes. Activation of Myc therefore profoundly changes the program of genes that are expressed in cancer cells.”
Researchers also reintroduced several repressed miRNAs into mouse lymphomas with high levels of Myc. When they measured the effect on the progression of lymphoma they found at least five of the miRNAs could stop cancer from growing.
Mendell says RNA-based therapies have had some success in animals and it is possible to find a wide range of miRNAs that can stop cancers in their tracks.
The study also finds in several cases, re-introducing repressed miRNAs into Myc-containing cancer cells suppressed tumor growth in mice – this means it is possible that a gene-therapy approach could be effective in treating some cancers.
Researchers analyzed more than 300 miRNAs in lymphoma cells of humans and mice. They had previously found Myc could turn on one particular group of growth-promoting miRNAs in lymphoma cells. In the cells with high amounts of Myc protein, researchers found big changes in the quantities of at least 13 miRNAs.
When researchers took a closer look at the DNA of the lymphoma cells, they found Myc was directly attaching to the DNA at the miRNA genes.
“This study expands our understanding of how Myc acts as such a potent cancer-promoting protein,” lead researcher Joshua Mendell, Johns Hopkins University, was quoted as saying. “We already knew that it can directly regulate thousands of genes. Through its repertoire of miRNAs, Myc likely influences the expression of thousands of additional genes. Activation of Myc therefore profoundly changes the program of genes that are expressed in cancer cells.”
Researchers also reintroduced several repressed miRNAs into mouse lymphomas with high levels of Myc. When they measured the effect on the progression of lymphoma they found at least five of the miRNAs could stop cancer from growing.
Mendell says RNA-based therapies have had some success in animals and it is possible to find a wide range of miRNAs that can stop cancers in their tracks.
Tuesday, December 18, 2007
Cardiovascular Disease Update
Cardiovascular disease (CVD) death rates are declining, but CVD is still the No. 1 cause of death in the United States, and risk factor control remains a challenge for many, according to the most recent data available online from the American Heart Association's Heart Disease and Stroke Statistics - 2008 Update.
Monday, December 17, 2007
Climate Change Preparedness
Climate change refers to any significant change in measures of climate, such as temperature, precipitation, or wind, that lasts for decades or longer.
Potential effects of climate change are likely to include more variable weather, heat waves, heavy precipitation events, flooding, droughts, intense storms such as hurricanes, rises in sea level, and air pollution.
Experts at the Centers for Disease Control and Prevention cannot predict how these changes will affect society and public health, but are preparing for the resulting health issues (podcast) that may be associated with global climate change.
Potential effects of climate change are likely to include more variable weather, heat waves, heavy precipitation events, flooding, droughts, intense storms such as hurricanes, rises in sea level, and air pollution.
Experts at the Centers for Disease Control and Prevention cannot predict how these changes will affect society and public health, but are preparing for the resulting health issues (podcast) that may be associated with global climate change.
Thursday, December 13, 2007
Hypertension Linked to Dementia
Elderly people with high blood pressure may be more likely to develop thinking and learning problems that can lead to dementia.
Hypertension was linked to one of two types of mild cognitive impairment, a condition that can foreshadow the development of dementia, but not the type strongly associated with Alzheimer's disease, according to the study published in the journal Archives of Neurology.
Hypertension was linked to one of two types of mild cognitive impairment, a condition that can foreshadow the development of dementia, but not the type strongly associated with Alzheimer's disease, according to the study published in the journal Archives of Neurology.
Wednesday, December 12, 2007
London to host ambitious research hub
The announcement last week that Europe's largest medical-research facility is to be built in central London has been largely welcomed by Britain's biomedical community, which hopes that the centre will accelerate the translational research — so beloved by policy-makers — that brings discoveries from the lab to patients. But the process has ruffled a few scientists' feathers.
Prime Minister Gordon Brown says that the government will sell a plot of land between the British Library and the international train station at St Pancras to a consortium of the Medical Research Council (MRC), Cancer Research UK (CRUK), the Wellcome Trust and University College London, for £85 million (US$173 million). The total cost of the UK Centre for Medical Research and Innovation, including purchase of the land, is pegged at more than £500 million. The MRC and CRUK are expected to shoulder the bulk of the cost, and the Wellcome Trust has committed £100 million to the project. The centre, which is expected to open in 2013, will employ up to 1,500 researchers and support staff.
It aims to compete with other global multidisciplinary scientific-research collaborations such as Biopolis in Singapore, the Allston Initiative at Harvard University and the Science-based Zizhu Industrial Park in Shanghai. “Being in central London, right alongside main teaching hospitals and main offices for clinical research, is a much better location for translational research,” MRC head Leszek Borysiewicz told Nature. “There is every opportunity for scientists to translate their work with the most appropriate clinical partners when they are that close to each other.”
Details of the research projects and teams that will be transferred to the centre remain scarce. Nobel laureate Paul Nurse, who is president of Rockefeller University in New York and CRUK's former director, will head an independent science-planning committee to determine the shape and direction of the centre's work and the facilities needed to carry it out.
The project will face numerous hurdles. Some researchers have expressed concerns that the infusion of funding into a prestigious project with limited space could ultimately hamper some basic research already taking place. And choosing to site the centre — which will include the largest animal-research laboratory in Europe and a category-4 virus containment laboratory — next to an international transport hub has sparked biosafety concerns.
Unease about potential staff reductions and shelving of core research has been particularly pronounced at the MRC's largest research body, the National Institute for Medical Research (NIMR), which will account for the bulk of the MRC's contribution to the new centre. The NIMR's 750 scientists and staff have already experienced nearly four years of debate within the MRC over its plans to move the institute from its current 19-hectare site in Mill Hill, northwest London, to central London. An earlier plan to move the institute to a site next to Euston Station in conjunction with University College London was ditched in March after the proposal faced scathing criticism from a key committee in the House of Commons that had held hearings on the plan.
NIMR staffers have previously expressed concerns that the 1.4-hectare site at St Pancras would have insufficient space for the institute's current facilities. Scientists have also criticized MRC executives for poor internal communication over the course of the discussions on the institute's fate, and say that the continuing uncertainty over how much of the NIMR will be transferred to the new research centre is taking a toll on morale. “It's going to be a very difficult management process to keep people happy,” says Robin Lovell-Badge, head of stem-cell biology and developmental genetics at the NIMR. “We are very nervous about it. Of course we can see the advantages and we want to be optimistic, but a lot of people at the institute just don't trust the MRC because of its past history.”
Translational medicine
Borysiewicz says that Nurse's committee is expected to draw up broad outlines of the new centre's scientific mission over the weeks to come, and he adds that NIMR researchers will be represented on the committee. “It may be five or six years before the new site is ready,” he says. “It is the MRC's intention to support the science at the NIMR during that period.”
Others think that the move will help their work. Neil McDonald, a structural biologist at CRUK, notes that his current central London lab needs major refurbishment, and says that the new centre was being viewed positively by CRUK's several hundred researchers. “The advantage of a big research institute, and the synergies involved, are not just economies of scale but accessibility to facilities that you wouldn't be able to afford at a smaller institute,” he says. “If you are in the same building and you see people in the canteen every day, it promotes collaborations and interactions, not just between research scientists but between scientists and clinicians.”
The proposed centre still needs planning permission to go ahead, but with Brown's backing, it is likely to succeed.
It aims to compete with other global multidisciplinary scientific-research collaborations such as Biopolis in Singapore, the Allston Initiative at Harvard University and the Science-based Zizhu Industrial Park in Shanghai. “Being in central London, right alongside main teaching hospitals and main offices for clinical research, is a much better location for translational research,” MRC head Leszek Borysiewicz told Nature. “There is every opportunity for scientists to translate their work with the most appropriate clinical partners when they are that close to each other.”
Details of the research projects and teams that will be transferred to the centre remain scarce. Nobel laureate Paul Nurse, who is president of Rockefeller University in New York and CRUK's former director, will head an independent science-planning committee to determine the shape and direction of the centre's work and the facilities needed to carry it out.
The project will face numerous hurdles. Some researchers have expressed concerns that the infusion of funding into a prestigious project with limited space could ultimately hamper some basic research already taking place. And choosing to site the centre — which will include the largest animal-research laboratory in Europe and a category-4 virus containment laboratory — next to an international transport hub has sparked biosafety concerns.
Unease about potential staff reductions and shelving of core research has been particularly pronounced at the MRC's largest research body, the National Institute for Medical Research (NIMR), which will account for the bulk of the MRC's contribution to the new centre. The NIMR's 750 scientists and staff have already experienced nearly four years of debate within the MRC over its plans to move the institute from its current 19-hectare site in Mill Hill, northwest London, to central London. An earlier plan to move the institute to a site next to Euston Station in conjunction with University College London was ditched in March after the proposal faced scathing criticism from a key committee in the House of Commons that had held hearings on the plan.
NIMR staffers have previously expressed concerns that the 1.4-hectare site at St Pancras would have insufficient space for the institute's current facilities. Scientists have also criticized MRC executives for poor internal communication over the course of the discussions on the institute's fate, and say that the continuing uncertainty over how much of the NIMR will be transferred to the new research centre is taking a toll on morale. “It's going to be a very difficult management process to keep people happy,” says Robin Lovell-Badge, head of stem-cell biology and developmental genetics at the NIMR. “We are very nervous about it. Of course we can see the advantages and we want to be optimistic, but a lot of people at the institute just don't trust the MRC because of its past history.”
Translational medicine
Borysiewicz says that Nurse's committee is expected to draw up broad outlines of the new centre's scientific mission over the weeks to come, and he adds that NIMR researchers will be represented on the committee. “It may be five or six years before the new site is ready,” he says. “It is the MRC's intention to support the science at the NIMR during that period.”
Others think that the move will help their work. Neil McDonald, a structural biologist at CRUK, notes that his current central London lab needs major refurbishment, and says that the new centre was being viewed positively by CRUK's several hundred researchers. “The advantage of a big research institute, and the synergies involved, are not just economies of scale but accessibility to facilities that you wouldn't be able to afford at a smaller institute,” he says. “If you are in the same building and you see people in the canteen every day, it promotes collaborations and interactions, not just between research scientists but between scientists and clinicians.”
The proposed centre still needs planning permission to go ahead, but with Brown's backing, it is likely to succeed.
Nuclear-reactor closure hits cancer tests
Hospitals across North America have been forced to cancel tests for cancer and heart disease because the unexpected closure of a Canadian nuclear reactor has led to a sudden shortage of medical isotopes.
The 50-year-old National Research Universal (NRU) reactor located in Chalk River, Ontario, was shut down on 18 November for scheduled maintenance and was due back online by mid-December. But Atomic Energy Canada, which owns and operates the facility, extended the outage to install safety-related equipment, including upgrades to the reactor cooling pumps. The reactor supplies about 60% of the molybdenum isotopes used in medical applications globally, including molybdenum-99, which decays into technetium-99m and is used in about 16 million nuclear medicine procedures annually in the United States.
“It's a disaster for patients,” says Sandy McEwan, president of the Society of Nuclear Medicine. North American hospitals now have 20–30% of the medical isotopes they require, he says.
Hospitals use a generator to extract technetium-99m from a source of decaying molybdenum-99. A technetium-99m isotope has a useful life of about one week, but can be stretched to two. MDS Nordion, an Ottawa-based life-sciences firm and molybdenum supplier to Bristol-Myers Squibb Medical Imaging, says it expects shortages of the radioisotope until mid-January. Molybdenum-99 has a half-life of 66 hours and cannot be stockpiled. Reactors in Australia, South Africa and Brussels also produce molybdenum-99. The shortage has reignited a discussion over securing the US supply of medical isotopes by building a reactor in the United States.
The NRU reactor was to be decommissioned in 2005, but its operating licence was extended until problems with two replacement reactors — MAPLE 1 and 2 — could be solved. The two MAPLE reactors and a processing facility were designed to supply the entire global demand for molybdenum-99, iodine-131, iodine-125 and xenon-133. In June, Atomic Energy Canada said that it expected MAPLE 1 and the processing facility to be in service by October 2008, and MAPLE 2 by October 2009.
The 50-year-old National Research Universal (NRU) reactor located in Chalk River, Ontario, was shut down on 18 November for scheduled maintenance and was due back online by mid-December. But Atomic Energy Canada, which owns and operates the facility, extended the outage to install safety-related equipment, including upgrades to the reactor cooling pumps. The reactor supplies about 60% of the molybdenum isotopes used in medical applications globally, including molybdenum-99, which decays into technetium-99m and is used in about 16 million nuclear medicine procedures annually in the United States.
“It's a disaster for patients,” says Sandy McEwan, president of the Society of Nuclear Medicine. North American hospitals now have 20–30% of the medical isotopes they require, he says.
Hospitals use a generator to extract technetium-99m from a source of decaying molybdenum-99. A technetium-99m isotope has a useful life of about one week, but can be stretched to two. MDS Nordion, an Ottawa-based life-sciences firm and molybdenum supplier to Bristol-Myers Squibb Medical Imaging, says it expects shortages of the radioisotope until mid-January. Molybdenum-99 has a half-life of 66 hours and cannot be stockpiled. Reactors in Australia, South Africa and Brussels also produce molybdenum-99. The shortage has reignited a discussion over securing the US supply of medical isotopes by building a reactor in the United States.
The NRU reactor was to be decommissioned in 2005, but its operating licence was extended until problems with two replacement reactors — MAPLE 1 and 2 — could be solved. The two MAPLE reactors and a processing facility were designed to supply the entire global demand for molybdenum-99, iodine-131, iodine-125 and xenon-133. In June, Atomic Energy Canada said that it expected MAPLE 1 and the processing facility to be in service by October 2008, and MAPLE 2 by October 2009.
FDA: Heartburn Drugs Show No Increased Risk For Heart Problems
FDA has completed a comprehensive, scientific review of known safety data for the drugs Prilosec and Nexium.
The FDA concluded that long-term use of these drugs is not likely to be associated with an increased risk of heart problems.
FDA recommends that health care providers continue to prescribe, and patients continue to use, these products as described in the labeling.
The FDA concluded that long-term use of these drugs is not likely to be associated with an increased risk of heart problems.
FDA recommends that health care providers continue to prescribe, and patients continue to use, these products as described in the labeling.
Monday, December 10, 2007
Clinical assessment of infant colour at delivery
Use of video recordings of newborn infants to determine: (1) if clinicians agreed whether infants were pink; and (2) the pulse oximeter oxygen saturation (SpO2) at which infants first looked pink...Among clinicians observing the same videos there was disagreement about whether newborn infants looked pink with wide variation in the SpO2 when they were considered to become pink
"Behind the Counter" Drug Category Proposed
This week's AMNews reports that the Food and Drug Administration is contemplating the establishment of a class of medications that would be available only after counseling from a pharmacist but without a physician's prescription.
While pharmacists tend to be most in favor of this, physicians argue it would make an already fragmented health care system even more so.
They also say the need to see a doctor first is not the most significant barrier to patients getting needed care.
While pharmacists tend to be most in favor of this, physicians argue it would make an already fragmented health care system even more so.
They also say the need to see a doctor first is not the most significant barrier to patients getting needed care.
HIV drug development: the next 25 years
The development of drugs for HIV infection began soon after the virus was discovered 25 years ago. Since then, progress has been substantial, but numerous uncertainties persist about the best way to manage this disease. Here we review the current treatment options, consider novel mechanisms that can be exploited for existing drug targets, and explore the potential of novel targets. With a view to the next quarter century, we consider whether drug resistance can be avoided, which drug classes will be favoured over others, which strategies are most likely to succeed, and the potential impact of pharmacogenomics and individualized therapy.(Charles Flexner)
With health care emerging as a major issue in the 2008 presidential race, NEWSWEEK asked seven Harvard experts to identify specific problems that ought to be addressed, and the steps that should be taken to solve them. The in-depth response to this survey is available on the website and outlines the following topics:
1:Ensure That Every American Has Health Insurance
2:Eliminate Racial Disparities
3:Fix the Medicare Drug Benefit
4:Use Quality-of-Care Report Cards
5:Wire American Medicine
6:Make Sure New Treatments Are Properly Studied
7:Curb Drug Spending Without Hurting Drug Development
1:Ensure That Every American Has Health Insurance
2:Eliminate Racial Disparities
3:Fix the Medicare Drug Benefit
4:Use Quality-of-Care Report Cards
5:Wire American Medicine
6:Make Sure New Treatments Are Properly Studied
7:Curb Drug Spending Without Hurting Drug Development
Bacterial pili, filamentous adhesive structures that extend from the cell surface, are important virulence factors and potential vaccine targets. Pili from Gram-negative bacteria have been structurally characterized. Now
Kang \u003cem\>et al.\u003c/em\>\u003c/b\> (p. \u003ca href\u003d\"http://www.sciencemag.org/cgi/content/short/318/5856/1625\" target\u003d\"_blank\" onclick\u003d\"return top.js.OpenExtLink(window,event,this)\"\>1625\u003c/a\>; \nsee the Perspective by \u003cb\>\u003ca href\u003d\"http://www.sciencemag.org/cgi/content/full/318/5856/1558\" target\u003d\"_blank\" onclick\u003d\"return top.js.OpenExtLink(window,event,this)\"\>Yeates and \nClubb\u003c/a\>\u003c/b\>) describe the structure of the major pilin subunit from a \nGram-positive human pathogen, \u003cem\>Streptococcus pyogenes\u003c/em\>. In the \ncrystal, the subunits associate in columns reminiscent of the likely \narrangement in native pili. The structure also reveals intramolecular \nisopeptide bonds that may stabilize the structure and contribute to \nprotease resistance. This could be a more general mechanism of protein \nstabilization in Gram-positive organisms, which lack the disulfide bond \nformation machinery of Gram-negative bacteria.\u003cp\>\n\u003cfont size\u003d\"-2\"\>CREDIT: KANG \u003cem\>ET \nAL.\u003c/em\>\u003c/font\>\u003c/p\>\u003c/td\>\u003c/tr\>\u003c/table\>\u003c/blockquote\>\n\u003chr\>\n\n\n\n\n\u003cp\>\n\n\n\u003chr\>\n\n\u003ch3\>Dissecting X Inactivation\u003c/h3\>\n\n\u003cp\>\n\n\n\n\n\nOne of the two X chromosomes in mammalian females is randomly inactivated \n\nearly in development to match the single active X chromosome of males. \n\nThis process is regulated through the X-inactivation center (Xic). The two\n\nXics interact in \u003cem\>trans\u003c/em\> at the beginning of X-inactivation, \n\npresumably to allow reciprocal activation/inactivation. So far, single \n\ncopies of elements from the Xic have not been able to recapitulate X \n\ninactivation, suggesting additional elements must be required. \u003cb\>Augui \n\n\u003cem\>et al.\u003c/em\>\u003c/b\> (p. \u003ca href\u003d\"http://www.sciencemag.org/cgi/content/short/318/5856/1632\" target\u003d\"_blank\" onclick\u003d\"return top.js.OpenExtLink(window,event,this)\"\>1632\u003c/a\>)\n\nfind that a region ~200 kilobases upstream of the Xic--the \n\nX-pairing-region (\u003cem\>Xpr\u003c/em\>) --is sufficient in a single copy to allow \n\na transient interaction between the two Xics at a time before the \n\nbeginning of X inactivation. This pairing is cell cycle dependent, can \n\noccur from an ectopic location, and may activate the expression of \n\n",1]
);
//-->
Kang et al. (p. 1625; see the Perspective by Yeates and Clubb) describe the structure of the major pilin subunit from a Gram-positive human pathogen, Streptococcus pyogenes. In the crystal, the subunits associate in columns reminiscent of the likely arrangement in native pili. The structure also reveals intramolecular isopeptide bonds that may stabilize the structure and contribute to protease resistance. This could be a more general mechanism of protein stabilization in Gram-positive organisms, which lack the disulfide bond formation machinery of Gram-negative bacteria.
Kang \u003cem\>et al.\u003c/em\>\u003c/b\> (p. \u003ca href\u003d\"http://www.sciencemag.org/cgi/content/short/318/5856/1625\" target\u003d\"_blank\" onclick\u003d\"return top.js.OpenExtLink(window,event,this)\"\>1625\u003c/a\>; \nsee the Perspective by \u003cb\>\u003ca href\u003d\"http://www.sciencemag.org/cgi/content/full/318/5856/1558\" target\u003d\"_blank\" onclick\u003d\"return top.js.OpenExtLink(window,event,this)\"\>Yeates and \nClubb\u003c/a\>\u003c/b\>) describe the structure of the major pilin subunit from a \nGram-positive human pathogen, \u003cem\>Streptococcus pyogenes\u003c/em\>. In the \ncrystal, the subunits associate in columns reminiscent of the likely \narrangement in native pili. The structure also reveals intramolecular \nisopeptide bonds that may stabilize the structure and contribute to \nprotease resistance. This could be a more general mechanism of protein \nstabilization in Gram-positive organisms, which lack the disulfide bond \nformation machinery of Gram-negative bacteria.\u003cp\>\n\u003cfont size\u003d\"-2\"\>CREDIT: KANG \u003cem\>ET \nAL.\u003c/em\>\u003c/font\>\u003c/p\>\u003c/td\>\u003c/tr\>\u003c/table\>\u003c/blockquote\>\n\u003chr\>\n\n\n\n\n\u003cp\>\n\n\n\u003chr\>\n\n\u003ch3\>Dissecting X Inactivation\u003c/h3\>\n\n\u003cp\>\n\n\n\n\n\nOne of the two X chromosomes in mammalian females is randomly inactivated \n\nearly in development to match the single active X chromosome of males. \n\nThis process is regulated through the X-inactivation center (Xic). The two\n\nXics interact in \u003cem\>trans\u003c/em\> at the beginning of X-inactivation, \n\npresumably to allow reciprocal activation/inactivation. So far, single \n\ncopies of elements from the Xic have not been able to recapitulate X \n\ninactivation, suggesting additional elements must be required. \u003cb\>Augui \n\n\u003cem\>et al.\u003c/em\>\u003c/b\> (p. \u003ca href\u003d\"http://www.sciencemag.org/cgi/content/short/318/5856/1632\" target\u003d\"_blank\" onclick\u003d\"return top.js.OpenExtLink(window,event,this)\"\>1632\u003c/a\>)\n\nfind that a region ~200 kilobases upstream of the Xic--the \n\nX-pairing-region (\u003cem\>Xpr\u003c/em\>) --is sufficient in a single copy to allow \n\na transient interaction between the two Xics at a time before the \n\nbeginning of X inactivation. This pairing is cell cycle dependent, can \n\noccur from an ectopic location, and may activate the expression of \n\n",1]
);
//-->
Kang et al. (p. 1625; see the Perspective by Yeates and Clubb) describe the structure of the major pilin subunit from a Gram-positive human pathogen, Streptococcus pyogenes. In the crystal, the subunits associate in columns reminiscent of the likely arrangement in native pili. The structure also reveals intramolecular isopeptide bonds that may stabilize the structure and contribute to protease resistance. This could be a more general mechanism of protein stabilization in Gram-positive organisms, which lack the disulfide bond formation machinery of Gram-negative bacteria.
A recent survey of practicing physicians in the United States found that most physicians agreed with principles regarding fair distribution of resources, access to and quality of care, conflicts of interest, and self-regulation that were proposed by professional societies in 2002.
Although 96% of respondents agreed that physicians should report impaired or incompetent colleagues to relevant authorities, 45% of respondents who encountered such colleagues had not reported them.
Self-reported behaviors, however, showed that about one half did not follow self-regulation principles and that about one third would order unneeded magnetic resonance imaging for back pain in response to a patient's request.
Although 96% of respondents agreed that physicians should report impaired or incompetent colleagues to relevant authorities, 45% of respondents who encountered such colleagues had not reported them.
Self-reported behaviors, however, showed that about one half did not follow self-regulation principles and that about one third would order unneeded magnetic resonance imaging for back pain in response to a patient's request.
Saturday, October 27, 2007
TUESDAY, Oct. 9 (HealthDay News) -- Prostate cancer patients receiving androgen-deprivation therapy, a common form of hormone treatment proven to slow tumor growth and prolong life, may face a nearly threefold higher risk of dying from heart disease, a new study suggests.
The apparent danger results from a drop in testosterone levels that is central to androgen-deprivation therapy's (ADT) effectiveness at curbing prostate cancer, the study authors said.
This drop in testosterone can provoke insulin resistance, leading to type 2 diabetes, as well as a gain in body mass, body fat and so-called bad cholesterol. Collectively, this group of problems is called the "metabolic syndrome," a condition long-associated with cardiac complications.
"However, I think overall ADT does help people with prostate cancer, and until it's studied further this can't be considered proof that there's a connection between the cardiac effects and hormone therapy," said study author Dr. Henry K. Tsai, who throughout the study period served as a resident in training in the Harvard Radiation Oncology Program in Boston.
"But patients need to think about being evaluated carefully by their doctor to see whether they're appropriate candidates for hormone therapy and be informed about the potential risks," Tsai added.
This new finding, published in the Oct. 17 issue of the Journal of the National Cancer Institute, follows research released in 2005 that highlighted ADT's link to an increased risk for bone fractures and osteoporosis.
The new findings are based on an analysis of medical records and questionnaires completed by nearly 4,900 patients between the ages of 39 and 86 who had been diagnosed with localized prostate cancer between 1995 and 2004.
All the patients had participated in a larger nationwide prostate cancer research project involving more than 13,000 men, during which all had indicated whether they had any preexisting medical complications in addition to cancer.
Of the 4,900 patients, nearly 3,300 had undergone prostate removal surgery following diagnosis.
The remainder underwent nonsurgical treatments, such as external beam radiation therapy; brachytherapy (involving the insertion of small radioactive pellets directly into the prostate); and/or cryotherapy (involving the freezing of tumor cells).
In addition, 266 of those patients who underwent surgery and 749 of those receiving an alternate treatment also received androgen-deprivation therapy.
The patients were tracked for an average of about four years following the start of all treatments; the patients receiving ADT did so for an average of about four months.
Tsai and his colleagues found that patients over the age of 65 who had undergone both prostate removal surgery and ADT had a 5.5 percent increased risk of dying from a cardiac event within five years of starting the hormone treatment. This compared to a 2 percent greater risk among patients older than 65 who had surgery alone.
The "relative risk" jump was similar among younger patients. Those under 65 who had surgery and hormone therapy had a 3.6 percent greater risk of death from heart disease within five years, compared with a 1.2 percent risk among those undergoing surgery alone.
ADT was not associated with any increased cardiac risk among patients undergoing any of the nonsurgical treatments.
An editorial accompanying the study calls for more research into the topic.
Jerome Seidenfeld and his colleagues at the University of Connecticut Health Center suggest that while Tsai's analysis of previously collected data raises an "interesting hypothesis," no definitive link to cancer risk can be proved until a clinical trial of prostate cancer patients currently undergoing hormone treatment is launched.
Tsai agreed.
"I pretty much feel similarly," Tsai said. "The editorial emphasizes that this is a preliminary study, and clinical trials are the gold standard. And we need one to confirm our findings."
Tsai, currently working as a radiation oncologist with Radiation Oncology Consultants in Princeton, N.J., said he doesn't want prostate cancer patients to view androgen-deprivation therapy with alarm.
"I don't think patients should be afraid," he said. "This is just what I'd call emerging data, and while the relative increase in risk for heart disease is large, in absolute terms the risk is still very small."
Dr. Nelson Neal Stone, a clinical professor of urology and radiation oncology at Mount Sinai School of Medicine in New York City, said the exact mechanism by which ADT might boost the risk for cardiac complications remains undefined, despite a widespread appreciation for the array of problems that accompany the metabolic syndrome.
In that light, he suggested that physicians should target the onset of the life-threatening syndrome as well as the life-prolonging treatment.
"The message is that we need to start paying attention to our patients' general health when we put them on hormonal therapy," he said. "And perhaps we should be putting them on a diet to control for the potential side effects of the therapy, and the serious impact it can have on their health."
"We can't take away the hormones altogether because there's a major benefit to that treatment," Stone added. "But we need to develop a good strategy for dealing with the negative consequences that occur."
The apparent danger results from a drop in testosterone levels that is central to androgen-deprivation therapy's (ADT) effectiveness at curbing prostate cancer, the study authors said.
This drop in testosterone can provoke insulin resistance, leading to type 2 diabetes, as well as a gain in body mass, body fat and so-called bad cholesterol. Collectively, this group of problems is called the "metabolic syndrome," a condition long-associated with cardiac complications.
"However, I think overall ADT does help people with prostate cancer, and until it's studied further this can't be considered proof that there's a connection between the cardiac effects and hormone therapy," said study author Dr. Henry K. Tsai, who throughout the study period served as a resident in training in the Harvard Radiation Oncology Program in Boston.
"But patients need to think about being evaluated carefully by their doctor to see whether they're appropriate candidates for hormone therapy and be informed about the potential risks," Tsai added.
This new finding, published in the Oct. 17 issue of the Journal of the National Cancer Institute, follows research released in 2005 that highlighted ADT's link to an increased risk for bone fractures and osteoporosis.
The new findings are based on an analysis of medical records and questionnaires completed by nearly 4,900 patients between the ages of 39 and 86 who had been diagnosed with localized prostate cancer between 1995 and 2004.
All the patients had participated in a larger nationwide prostate cancer research project involving more than 13,000 men, during which all had indicated whether they had any preexisting medical complications in addition to cancer.
Of the 4,900 patients, nearly 3,300 had undergone prostate removal surgery following diagnosis.
The remainder underwent nonsurgical treatments, such as external beam radiation therapy; brachytherapy (involving the insertion of small radioactive pellets directly into the prostate); and/or cryotherapy (involving the freezing of tumor cells).
In addition, 266 of those patients who underwent surgery and 749 of those receiving an alternate treatment also received androgen-deprivation therapy.
The patients were tracked for an average of about four years following the start of all treatments; the patients receiving ADT did so for an average of about four months.
Tsai and his colleagues found that patients over the age of 65 who had undergone both prostate removal surgery and ADT had a 5.5 percent increased risk of dying from a cardiac event within five years of starting the hormone treatment. This compared to a 2 percent greater risk among patients older than 65 who had surgery alone.
The "relative risk" jump was similar among younger patients. Those under 65 who had surgery and hormone therapy had a 3.6 percent greater risk of death from heart disease within five years, compared with a 1.2 percent risk among those undergoing surgery alone.
ADT was not associated with any increased cardiac risk among patients undergoing any of the nonsurgical treatments.
An editorial accompanying the study calls for more research into the topic.
Jerome Seidenfeld and his colleagues at the University of Connecticut Health Center suggest that while Tsai's analysis of previously collected data raises an "interesting hypothesis," no definitive link to cancer risk can be proved until a clinical trial of prostate cancer patients currently undergoing hormone treatment is launched.
Tsai agreed.
"I pretty much feel similarly," Tsai said. "The editorial emphasizes that this is a preliminary study, and clinical trials are the gold standard. And we need one to confirm our findings."
Tsai, currently working as a radiation oncologist with Radiation Oncology Consultants in Princeton, N.J., said he doesn't want prostate cancer patients to view androgen-deprivation therapy with alarm.
"I don't think patients should be afraid," he said. "This is just what I'd call emerging data, and while the relative increase in risk for heart disease is large, in absolute terms the risk is still very small."
Dr. Nelson Neal Stone, a clinical professor of urology and radiation oncology at Mount Sinai School of Medicine in New York City, said the exact mechanism by which ADT might boost the risk for cardiac complications remains undefined, despite a widespread appreciation for the array of problems that accompany the metabolic syndrome.
In that light, he suggested that physicians should target the onset of the life-threatening syndrome as well as the life-prolonging treatment.
"The message is that we need to start paying attention to our patients' general health when we put them on hormonal therapy," he said. "And perhaps we should be putting them on a diet to control for the potential side effects of the therapy, and the serious impact it can have on their health."
"We can't take away the hormones altogether because there's a major benefit to that treatment," Stone added. "But we need to develop a good strategy for dealing with the negative consequences that occur."
MONDAY, Sept. 24 (HealthDay News) -- Prostate cancer prevention studies conducted since the 1990s are poised to revolutionize the field in the next five years, a Canadian analysis concludes.
"I am optimistic that for the coming generation, beginning with men in their 20s and 30s, we will have a viable strategy to decrease the chance of developing prostate cancer later in life," said study lead author Dr. Neil Fleshner.
A professor of surgery, Fleshner heads the division of urology at Princess Margaret Hospital, part of the University Health Network at the University of Toronto.
His team's overview of the last 15 years of prostate cancer prevention research is published in the Nov. 1 issue of Cancer.
According to the U.S. National Cancer Institute (NCI), cancer of the prostate is the most common non-skin cancer among American men. Most patients diagnosed with the disease do not ultimately die of it. However, because of its high prevalence, prostate cancer remains the third biggest cancer killer for men in the Western world.
By age 40, one-third of men have already developed small carcinomas of the prostate, the researchers noted. By age 60, that figure rises to 60 percent, and, in North America, one in seven men will develop prostate cancer at some point in their lives.
But the disease is also often slow-moving, sometimes taking decades to develop from a single prostate cancer cell to advanced-stage illness.
That fact has led to the hope that doctors could intervene in ways that could halt disease progression at an early stage.
One such study reviewed by Fleshner and his colleagues was the Prostate Cancer Prevention Trial (PCPT), overseen by the NCI.
In this instance, NCI researchers looked at the ability of finasteride -- a so-called 5-alpha reductase inhibitor (5ARI) medication -- to impede the growth-promoting impact of hormones such as testosterone on prostate cancer.
Designed to interfere with the body's ability to uptake testosterone and other male hormones, finasteride was offered to half the almost 19,000 men over the age of 55 who participated in the seven-year study.
At the study's start, all the men screened as "normal" following digital rectal exams. As well, all had registered low-scoring prostate-specific antigen (PSA) levels. An elevated level of PSA in the blood is an indication of prostate cancer.
Yearly digital rectal exams and PSA screenings revealed that almost 25 percent of the men on placebo went on to develop prostate cancer. However, just a little over 18 percent of those taking finasteride got the disease.
Fleshner and his associates noted, however, that most of the cancer cases prevented appeared to be of the early stage, low-grade variety. More serious, higher-grade disease actually appeared to become more common among patients taking finasteride. This raises concern that the medication might actually hasten disease progression, the Canadian group cautioned.
Nevertheless, their review concluded that finasteride might, in the near future, become an effective prevention tool for men with a strong family history of the disease.
Additional studies are currently under way to explore the benefits of newer hormone manipulation drugs, they noted, including the 5ARI drug dutasteride and the selective estrogen receptor modifier toremifene. Results should be available in a few years.
Meanwhile, the Canadian team also uncovered evidence suggesting that limiting fat in the diet might also reduce prostate cancer risk. Various studies have highlighted unhealthful connections between fat and pesticide exposure, testosterone level increases, and the rise of oxidative stress -- all of which seem to contribute to prostate disease risk.
By contrast, evidence has mounted that increasing vitamin E and selenium intake could also protect against prostate cancer, they said. Recent research also suggests that consuming more green tea, soy, vitamin D, and lycopene (typically found in tomatoes) might confer similar benefits.
Fleshner and his colleagues hailed the new emphasis on prevention. The arrival of even more helpful prevention information might be just around the corner, they said.
"What's exciting now is that there's no doubt any longer that prostate disease is preventable," said Fleshner. "This will not necessarily translate into improved mortality rates, because it may be that we will be able to prevent more low-grade disease than high-grade."
But many men with low-grade disease currently undergo surgery and other treatments that can impact their quality of life, he noted. "So, even if we are able to reduce just the need for unnecessary treatment, this will be a good step," Fleshner said.
Not everyone shares that optimism, however.
Dr. Nelson Neal Stone, a clinical professor of urology and radiation oncology at the Mount Sinai School of Medicine in New York City, believes that when it comes to preventing prostate cancer, "we're still sort of at a loss."
"Today, you can't really advise a patient to do anything to prevent prostate cancer," he said. "The best study so far -- the PCPT study-- did show a 25 percent drop in prostate cancer, but that was in low-grade tumors, whereas the incidence of high-grade tumors may actually have gone up. And a lot of the dietary factors that showed promise --vitamins, selenium -- have come into question as to whether they're really helping patients."
"So, I would agree that in five year's time, we will probably come up with strategies to reduce the clinical incidence of the disease in terms of detecting low-grade cancer," he added. "But that doesn't have much meaning in a patient's life. What has meaning is the ability to prevent a high-grade tumor from metastasizing and potentially ending a patient's life. And nobody has shown that anything can reduce that."
"In my opinion, the best strategy we have now is early detection," Stone said. "If you find a patient with an aggressive prostate cancer, and it's small and in the prostate and you find it early, you save that patient's life."
"I am optimistic that for the coming generation, beginning with men in their 20s and 30s, we will have a viable strategy to decrease the chance of developing prostate cancer later in life," said study lead author Dr. Neil Fleshner.
A professor of surgery, Fleshner heads the division of urology at Princess Margaret Hospital, part of the University Health Network at the University of Toronto.
His team's overview of the last 15 years of prostate cancer prevention research is published in the Nov. 1 issue of Cancer.
According to the U.S. National Cancer Institute (NCI), cancer of the prostate is the most common non-skin cancer among American men. Most patients diagnosed with the disease do not ultimately die of it. However, because of its high prevalence, prostate cancer remains the third biggest cancer killer for men in the Western world.
By age 40, one-third of men have already developed small carcinomas of the prostate, the researchers noted. By age 60, that figure rises to 60 percent, and, in North America, one in seven men will develop prostate cancer at some point in their lives.
But the disease is also often slow-moving, sometimes taking decades to develop from a single prostate cancer cell to advanced-stage illness.
That fact has led to the hope that doctors could intervene in ways that could halt disease progression at an early stage.
One such study reviewed by Fleshner and his colleagues was the Prostate Cancer Prevention Trial (PCPT), overseen by the NCI.
In this instance, NCI researchers looked at the ability of finasteride -- a so-called 5-alpha reductase inhibitor (5ARI) medication -- to impede the growth-promoting impact of hormones such as testosterone on prostate cancer.
Designed to interfere with the body's ability to uptake testosterone and other male hormones, finasteride was offered to half the almost 19,000 men over the age of 55 who participated in the seven-year study.
At the study's start, all the men screened as "normal" following digital rectal exams. As well, all had registered low-scoring prostate-specific antigen (PSA) levels. An elevated level of PSA in the blood is an indication of prostate cancer.
Yearly digital rectal exams and PSA screenings revealed that almost 25 percent of the men on placebo went on to develop prostate cancer. However, just a little over 18 percent of those taking finasteride got the disease.
Fleshner and his associates noted, however, that most of the cancer cases prevented appeared to be of the early stage, low-grade variety. More serious, higher-grade disease actually appeared to become more common among patients taking finasteride. This raises concern that the medication might actually hasten disease progression, the Canadian group cautioned.
Nevertheless, their review concluded that finasteride might, in the near future, become an effective prevention tool for men with a strong family history of the disease.
Additional studies are currently under way to explore the benefits of newer hormone manipulation drugs, they noted, including the 5ARI drug dutasteride and the selective estrogen receptor modifier toremifene. Results should be available in a few years.
Meanwhile, the Canadian team also uncovered evidence suggesting that limiting fat in the diet might also reduce prostate cancer risk. Various studies have highlighted unhealthful connections between fat and pesticide exposure, testosterone level increases, and the rise of oxidative stress -- all of which seem to contribute to prostate disease risk.
By contrast, evidence has mounted that increasing vitamin E and selenium intake could also protect against prostate cancer, they said. Recent research also suggests that consuming more green tea, soy, vitamin D, and lycopene (typically found in tomatoes) might confer similar benefits.
Fleshner and his colleagues hailed the new emphasis on prevention. The arrival of even more helpful prevention information might be just around the corner, they said.
"What's exciting now is that there's no doubt any longer that prostate disease is preventable," said Fleshner. "This will not necessarily translate into improved mortality rates, because it may be that we will be able to prevent more low-grade disease than high-grade."
But many men with low-grade disease currently undergo surgery and other treatments that can impact their quality of life, he noted. "So, even if we are able to reduce just the need for unnecessary treatment, this will be a good step," Fleshner said.
Not everyone shares that optimism, however.
Dr. Nelson Neal Stone, a clinical professor of urology and radiation oncology at the Mount Sinai School of Medicine in New York City, believes that when it comes to preventing prostate cancer, "we're still sort of at a loss."
"Today, you can't really advise a patient to do anything to prevent prostate cancer," he said. "The best study so far -- the PCPT study-- did show a 25 percent drop in prostate cancer, but that was in low-grade tumors, whereas the incidence of high-grade tumors may actually have gone up. And a lot of the dietary factors that showed promise --vitamins, selenium -- have come into question as to whether they're really helping patients."
"So, I would agree that in five year's time, we will probably come up with strategies to reduce the clinical incidence of the disease in terms of detecting low-grade cancer," he added. "But that doesn't have much meaning in a patient's life. What has meaning is the ability to prevent a high-grade tumor from metastasizing and potentially ending a patient's life. And nobody has shown that anything can reduce that."
"In my opinion, the best strategy we have now is early detection," Stone said. "If you find a patient with an aggressive prostate cancer, and it's small and in the prostate and you find it early, you save that patient's life."
FRIDAY, Sept. 14 (HealthDay News) -- Men who've been adding vitamin E or the tomato nutrient lycopene to their diets to cut their risk of prostate cancer may need to think again.
According to a new study, neither carotenoids (such as lycopene), retinol, nor tocopherols (forms of vitamin E) appear to reduce the odds of prostate malignancy -- findings that are in line with two other recent publications.
"Our overall findings are null," said lead researcher Timothy Key, deputy director of the Cancer Research UK Epidemiology Unit at the University of Oxford, U.K.
"This large study does not support the hypothesis that consuming large amounts of these nutrients will reduce prostate cancer," he added. "That is disappointing, but that is the overall message."
The findings are published in the September issue of the American Journal of Clinical Nutrition.
His team examined the effect of the blood levels of 10 micronutrients on the risk of developing prostate cancer for almost 2,000 males from eight European countries.
The research, which the authors call "the largest prospective study to date of plasma carotenoids, retinol, tocopherols, and prostate cancer risk," was part of the EPIC (European Prospective Investigation into Cancer and Nutrition) study, which includes more than half a million men and women.
The authors did find evidence to suggest that, once a cancer forms, high levels of lycopene (or of carotenoids in general, including lycopene) may reduce by about 60 percent the risk of the tumor progressing to an advanced-stage prostate cancer. Carotenoids appeared to have no effect on the rate of localized, earlier-stage disease, however.
According to Dr. Peter Scardino, head of the Prostate Cancer Program at Memorial Sloan-Kettering Cancer Center in New York City, prostate cancer is the most common cancer in men in the developed world. A Western male, he said, has about a 42 percent risk of developing cancerous cells in his prostate over his lifetime, a 16 percent risk of being diagnosed with the disease, and about a three percent risk of dying as a result. In other words, nearly one-quarter of Western males have a subclinical form of prostate cancer, which will never progress to more advanced disease.
Stopping progression is crucial. According to Scardino, for those whose disease does progress, the risk of death is much higher -- nearly 50 percent.
"I think it's an important study," Scardino said. That lycopene and bulk carotenoids reduced the risk of progressing to advanced disease without impacting the risk of developing prostate cancer overall, he said, "suggests maybe these micronutrients are not as important in [stopping] carcinogenesis as they are in [slowing] progression of a very small early tumor to one that becomes invasive and larger and develops the ability to metastasize."
"The study provides supportive evidence that lycopene and the carotenoids may have an effect on delaying the progression of prostate cancer, so, from that point of view, it is an interesting study," Scardino added.
But Alan Kristal, associate head of the Cancer Prevention Program at the Fred Hutchinson Cancer Research Center in Seattle, remained more skeptical. Though he called the study "well-executed," Kristal noted, for instance, that the authors were unable to control for prostate-specific antigen (PSA) testing among the men. These blood tests often detect clinically irrelevant tumors, he explained.
"You can never do an observational study of prostate cancer without rigorously controlling for whether or not the person got PSA screening," Kristal said. "The more times you take the test, the more likely you are to get the disease."
He also noted that the finding for lycopene contradicts a report published in May in Cancer Epidemiology Biomarkers and Prevention. That study did account for PSA testing, and it found no effect of lycopene whatsoever on prostate cancer risk -- including the risk of advanced disease.
"To my mind, that study is definitive," said Kristal. "It's a big study, extremely well executed, properly analyzed, and not biased by PSA screening."
A review of lycopene's effect on cancer by the U.S. Food and Drug Administration, published in July in the Journal of the National Cancer Institute, likewise found "no credible evidence to support an association between lycopene intake and a reduced risk of prostate, lung, colorectal, gastric, breast, ovarian, endometrial, or pancreatic cancer and very limited evidence to support an association between tomato consumption and reduced risks of prostate, ovarian, gastric, and pancreatic cancers," according to that study's authors.
So, with tomatoes, ketchup and pizza sauce crossed off the list of prostate-protecting foods, Key and others continue the search. Kristal, for instance, is on the executive committee of a randomized trial examining the effects of selenium and/or vitamin E on prostate cancer risk in 35,000 men. Results are expected in 2012, he said.
Said Key, "I am optimistic we will find something. This paper is an important piece of work, but it doesn't look like this is the answer."
According to a new study, neither carotenoids (such as lycopene), retinol, nor tocopherols (forms of vitamin E) appear to reduce the odds of prostate malignancy -- findings that are in line with two other recent publications.
"Our overall findings are null," said lead researcher Timothy Key, deputy director of the Cancer Research UK Epidemiology Unit at the University of Oxford, U.K.
"This large study does not support the hypothesis that consuming large amounts of these nutrients will reduce prostate cancer," he added. "That is disappointing, but that is the overall message."
The findings are published in the September issue of the American Journal of Clinical Nutrition.
His team examined the effect of the blood levels of 10 micronutrients on the risk of developing prostate cancer for almost 2,000 males from eight European countries.
The research, which the authors call "the largest prospective study to date of plasma carotenoids, retinol, tocopherols, and prostate cancer risk," was part of the EPIC (European Prospective Investigation into Cancer and Nutrition) study, which includes more than half a million men and women.
The authors did find evidence to suggest that, once a cancer forms, high levels of lycopene (or of carotenoids in general, including lycopene) may reduce by about 60 percent the risk of the tumor progressing to an advanced-stage prostate cancer. Carotenoids appeared to have no effect on the rate of localized, earlier-stage disease, however.
According to Dr. Peter Scardino, head of the Prostate Cancer Program at Memorial Sloan-Kettering Cancer Center in New York City, prostate cancer is the most common cancer in men in the developed world. A Western male, he said, has about a 42 percent risk of developing cancerous cells in his prostate over his lifetime, a 16 percent risk of being diagnosed with the disease, and about a three percent risk of dying as a result. In other words, nearly one-quarter of Western males have a subclinical form of prostate cancer, which will never progress to more advanced disease.
Stopping progression is crucial. According to Scardino, for those whose disease does progress, the risk of death is much higher -- nearly 50 percent.
"I think it's an important study," Scardino said. That lycopene and bulk carotenoids reduced the risk of progressing to advanced disease without impacting the risk of developing prostate cancer overall, he said, "suggests maybe these micronutrients are not as important in [stopping] carcinogenesis as they are in [slowing] progression of a very small early tumor to one that becomes invasive and larger and develops the ability to metastasize."
"The study provides supportive evidence that lycopene and the carotenoids may have an effect on delaying the progression of prostate cancer, so, from that point of view, it is an interesting study," Scardino added.
But Alan Kristal, associate head of the Cancer Prevention Program at the Fred Hutchinson Cancer Research Center in Seattle, remained more skeptical. Though he called the study "well-executed," Kristal noted, for instance, that the authors were unable to control for prostate-specific antigen (PSA) testing among the men. These blood tests often detect clinically irrelevant tumors, he explained.
"You can never do an observational study of prostate cancer without rigorously controlling for whether or not the person got PSA screening," Kristal said. "The more times you take the test, the more likely you are to get the disease."
He also noted that the finding for lycopene contradicts a report published in May in Cancer Epidemiology Biomarkers and Prevention. That study did account for PSA testing, and it found no effect of lycopene whatsoever on prostate cancer risk -- including the risk of advanced disease.
"To my mind, that study is definitive," said Kristal. "It's a big study, extremely well executed, properly analyzed, and not biased by PSA screening."
A review of lycopene's effect on cancer by the U.S. Food and Drug Administration, published in July in the Journal of the National Cancer Institute, likewise found "no credible evidence to support an association between lycopene intake and a reduced risk of prostate, lung, colorectal, gastric, breast, ovarian, endometrial, or pancreatic cancer and very limited evidence to support an association between tomato consumption and reduced risks of prostate, ovarian, gastric, and pancreatic cancers," according to that study's authors.
So, with tomatoes, ketchup and pizza sauce crossed off the list of prostate-protecting foods, Key and others continue the search. Kristal, for instance, is on the executive committee of a randomized trial examining the effects of selenium and/or vitamin E on prostate cancer risk in 35,000 men. Results are expected in 2012, he said.
Said Key, "I am optimistic we will find something. This paper is an important piece of work, but it doesn't look like this is the answer."
Monday, September 17, 2007
When a man becomes sexually aroused, increased blood flow to the genital area readies the body for intercourse. The penis becomes enlarged and erect. In men with erectile dysfunction (ED), however, this physical response doesn't happen as it should. And this isn't just a one-time or occasional occurrence. In fact, occasional failure to become aroused or desiring sex less often than your partner is perfectly normal. Stress, fatigue and anxiety can affect the body's response to sexual stimulation. The problem occurs when this lack of response happens persistently and on a regular basis for more than 25 percent of the time. With ED, intercourse is difficult or impossible.
ED is not only a common problem, particularly among older men, but also it is undertreated. The Massachusetts Male Aging Study of middle-aged and older men showed 35 percent of men ages 40 to 70 years had complete ED, which was strongly related to age, health status and emotional function. According to the American Medical Association (AMA), about 20 million American men, mostly older than 65, are affected. It is difficult to calculate an exact number because less than 10 percent seek treatment.
The following information is designed as a basic introduction to possible causes of and treatments for ED. If you suspect a problem, talk with your doctor or other health care professional.
Causes
Once thought to be a psychological condition, most cases of ED are now known to have a physical cause, such as a disease, an injury or a side effect from a drug. Certain medications can interfere with the nerve signals that cause an erection. Hardening of the arteries and high blood pressure can damage blood vessels and interfere with blood flow to the penis. Smoking is a major risk factor for these conditions as well as for ED. Diabetes can damage nerves and interfere with erection. Surgery for prostate cancer may cause ED. Other possible physical causes include alcoholism, liver failure, hormonal abnormalities (such as low testosterone) and neurological disorders. In most cases of ED, even when there is also a definite physical cause, men may feel anxious, guilty or depressed, which can make the problem worse.
Treatments
The AMA estimates 95 percent of ED cases are treatable through one of the following measures.
Drug therapy: Viagra® (sildenafil) was approved by the U.S. Food and Drug Administration in 1998. Taken an hour or so before sexual activity, it increases the concentration of a natural chemical in the penis that causes the blood vessels to dilate, which increases blood flow to the penis. Unlike injection therapy (see below), it doesn't cause an automatic erection. Rather, it works in response to sexual stimulation. However, sildenafil isn't right for everyone. Men who have heart problems and take medications that help widen the coronary arteries are not good candidates because the drug combination can lower blood pressure dangerously. Some men with hormonal imbalances may be helped by testosterone shots, or skin patches. In 2003 the FDA approved Levitra® (vardenafil) for the treatment of ED. The way it works is similar to sildenafil. The latest medication approved for erectile dysfunction is Cialis® (tadalafil). It differs from the other two drugs only because its effects persist for 36 hours, rather than just a few hours.
Psychotherapy: Whether there is a physical cause or not, men may benefit from working with a therapist to learn techniques that can decrease anxiety associated with intercourse.
Vacuum constriction device: This involves placing a plastic tube over the penis and pumping the air out of the tube, drawing blood into the penis and making it erect. An elastic band is placed around the base of the penis to maintain the erection.
Penile injection therapy: Medication injected directly into the side of the penis causes the blood vessels to widen and erection to occur.
Intraurethral therapy: A soft pellet of medication is inserted into the urethra. Its absorption produces an erection.
Surgery: Surgery may involve one of three procedures: implanting a device (prosthesis) that can cause the penis to become erect; reconstructing arteries to increase blood flow to the penis; or repairing the veins within the penis that are failing to keep sufficient blood within the organ. Artery reconstructions and vein repairs have generally not given good long-term benefits.
All these treatments have different complications and side effects. So men should work with their doctors to determine what's right for them.
Risk of blindness
In 2005, the Food and Drug Administration (FDA) approved updated labeling for Cialis, Levitra and Viagra to reflect a small number of reports of sudden vision loss, attributed to NAION (non arteritic ischemic optic neuropathy), a condition where blood flow is blocked to the optic nerve. The FDA advises patients to stop taking these medicines, and call a doctor or health care provider right away if they have sudden or decreased vision loss in one or both eyes. Further, patients taking or considering taking these products should inform their health care professionals if they have ever had severe loss of vision, which might reflect a prior episode of NAION. Such patients are at an increased risk of developing NAION again.
At this time, it is not possible to say if these medicines for erectile dysfunction were the cause of the loss of sight or whether the problem is related to other factors such as high blood pressure or diabetes, or to a combination of these problems.
ED is not only a common problem, particularly among older men, but also it is undertreated. The Massachusetts Male Aging Study of middle-aged and older men showed 35 percent of men ages 40 to 70 years had complete ED, which was strongly related to age, health status and emotional function. According to the American Medical Association (AMA), about 20 million American men, mostly older than 65, are affected. It is difficult to calculate an exact number because less than 10 percent seek treatment.
The following information is designed as a basic introduction to possible causes of and treatments for ED. If you suspect a problem, talk with your doctor or other health care professional.
Causes
Once thought to be a psychological condition, most cases of ED are now known to have a physical cause, such as a disease, an injury or a side effect from a drug. Certain medications can interfere with the nerve signals that cause an erection. Hardening of the arteries and high blood pressure can damage blood vessels and interfere with blood flow to the penis. Smoking is a major risk factor for these conditions as well as for ED. Diabetes can damage nerves and interfere with erection. Surgery for prostate cancer may cause ED. Other possible physical causes include alcoholism, liver failure, hormonal abnormalities (such as low testosterone) and neurological disorders. In most cases of ED, even when there is also a definite physical cause, men may feel anxious, guilty or depressed, which can make the problem worse.
Treatments
The AMA estimates 95 percent of ED cases are treatable through one of the following measures.
Drug therapy: Viagra® (sildenafil) was approved by the U.S. Food and Drug Administration in 1998. Taken an hour or so before sexual activity, it increases the concentration of a natural chemical in the penis that causes the blood vessels to dilate, which increases blood flow to the penis. Unlike injection therapy (see below), it doesn't cause an automatic erection. Rather, it works in response to sexual stimulation. However, sildenafil isn't right for everyone. Men who have heart problems and take medications that help widen the coronary arteries are not good candidates because the drug combination can lower blood pressure dangerously. Some men with hormonal imbalances may be helped by testosterone shots, or skin patches. In 2003 the FDA approved Levitra® (vardenafil) for the treatment of ED. The way it works is similar to sildenafil. The latest medication approved for erectile dysfunction is Cialis® (tadalafil). It differs from the other two drugs only because its effects persist for 36 hours, rather than just a few hours.
Psychotherapy: Whether there is a physical cause or not, men may benefit from working with a therapist to learn techniques that can decrease anxiety associated with intercourse.
Vacuum constriction device: This involves placing a plastic tube over the penis and pumping the air out of the tube, drawing blood into the penis and making it erect. An elastic band is placed around the base of the penis to maintain the erection.
Penile injection therapy: Medication injected directly into the side of the penis causes the blood vessels to widen and erection to occur.
Intraurethral therapy: A soft pellet of medication is inserted into the urethra. Its absorption produces an erection.
Surgery: Surgery may involve one of three procedures: implanting a device (prosthesis) that can cause the penis to become erect; reconstructing arteries to increase blood flow to the penis; or repairing the veins within the penis that are failing to keep sufficient blood within the organ. Artery reconstructions and vein repairs have generally not given good long-term benefits.
All these treatments have different complications and side effects. So men should work with their doctors to determine what's right for them.
Risk of blindness
In 2005, the Food and Drug Administration (FDA) approved updated labeling for Cialis, Levitra and Viagra to reflect a small number of reports of sudden vision loss, attributed to NAION (non arteritic ischemic optic neuropathy), a condition where blood flow is blocked to the optic nerve. The FDA advises patients to stop taking these medicines, and call a doctor or health care provider right away if they have sudden or decreased vision loss in one or both eyes. Further, patients taking or considering taking these products should inform their health care professionals if they have ever had severe loss of vision, which might reflect a prior episode of NAION. Such patients are at an increased risk of developing NAION again.
At this time, it is not possible to say if these medicines for erectile dysfunction were the cause of the loss of sight or whether the problem is related to other factors such as high blood pressure or diabetes, or to a combination of these problems.
Saturday, August 18, 2007
Prostate Cancer Treatments
How is prostate cancer treated?
Many options are available to treat prostate cancer. The treatment that will work best depends on several factors. These include your overall health status, age and the grade and stage of the prostate cancer when it is first diagnosed.
Take the time to research your treatment options. Get a second opinion before making a final decision. The most common treatment options for prostate cancer include watchful waiting, surgery, radiation and hormone therapy.
Watchful waiting
Since prostate cancer often grows slowly, older men over age 70 who have the disease may not need treatment. Your physician may suggest taking a wait-and-see attitude. This course of treatment will involve periodic examinations and testing to determine if the cancer has become more aggressive. If it does, active treatment can then be initiated.
Surgical treatments
Surgical treatments are used when the goal is to remove the cancer. A radical prostatectomy involves the removal of the entire prostate gland and surrounding tissue. This operation is performed only if the cancer is confined to the prostate gland itself. The surgery involves making an incision into the abdomen to gain access to the prostate gland. A urinary catheter will be in place after surgery so that urine can be drained from the body. The catheter is left in place for a few weeks. Once it is removed, there may be problems with dribbling and incontinence. This usually improves over time and can sometimes be corrected with medication or other procedures. Impotence or the inability to sustain an erection may result after radical prostate surgery due to impairment of the nerves that control erection. This condition may be temporary or, in some cases, permanent. Discuss these issues with your doctor before consenting to this type of treatment. A nerve-sparing operation, which saves the nerves that control the ability to have an erection, may reduce this risk of impotence.
Transurethral resection of the prostate (TURP) is another surgical option that may be used for men who are not candidates for radical prostate surgery. During this procedure, an instrument is inserted through the urethra and into the prostate where tissue is removed through cauterization. No incision is needed, and a catheter will be left in place for a few days until any urinary bleeding resolves. Incontinence and impotence are not generally associated with a TURP but do occur. The surgery, however, will not cure the patient since the prostate gland is not removed.
Cryosurgery
Cryosurgery is a relatively new treatment for prostate cancer that involves killing the cancer cells through freezing by rods inserted in the prostate.
Radiation therapy
Two types of radiation treatments can be used to treat prostate cancer. They involve external beam radiation, which is similar to getting an X-ray. Treatments, given on a daily basis, last several minutes, and the entire course of therapy may take six or seven weeks to complete. New technology is more exact, using CT scan localization called three dimensional conformal radiation therapy, which offers a 3-D computerized image.
Internal radiation uses radioactive seeds placed directly into the prostate gland. The pellets emit radiation for a few months and then are no longer active.
Radiation therapy does have side effects. Many patients complain of fatigue during the treatments. Others report gastrointestinal symptoms like diarrhea and nausea. Some patients may have difficulty with urination and maintaining erections.
Hormone therapy
Since prostate cancer is dependent upon the male hormone testosterone to grow, reducing the amount of testosterone can cause the tumor to shrink or grow more slowly. Testosterone levels can be reduced through surgery to remove the testicles (orchiectomy), since most testosterone is manufactured here. Hormone pills can also be given to reduce testosterone levels.
Hormone therapy is not a cure for prostate cancer but rather a way to slow its growth. Shots of Lupron® (leuprolide) or Zoledex® (goserelin) (LH-RH agonists) can block the pituitary gland from producing gonadal (testicular) growth stimulating hormones such as testosterone. Hormone treatments may have side effects. They can cause infertility, decreased libido, hot flashes, impotence and osteoporosis (thinning of the bones).
Chemotherapy
The administration of cancer-fighting drugs that kill cancer cells within the body is used only in cases of advanced prostate cancer when the disease has already spread to other organs. The goal of therapy is to reduce pain and hinder the tumor's growth. Recent studies have shown improved survival for patients with metastatic prostate cancer using Taxotere® (docetaxel).
What can I expect following treatment for prostate cancer?
After you complete your initial treatment for prostate cancer, your physician will continue to monitor you closely. You will need to have regular medical examinations that will include screening tests to check for return of the cancer, including the PSA (prostate specific antigen) blood test. If recurrent prostate cancer is found, treatment will depend on what options were chosen originally.
Are there any new developments in prostate cancer research?
HPC1 gene. Scientists have only recently discovered a gene called HPC1 that they hope will soon give additional information about the inherited risk of prostate cancer. One day there may be tests available to identify men at high risk of developing prostate cancer. Early screening procedures could then be implemented.
Angiogenesis. New drugs are being tested that may be able to halt the spread of prostate cancer by interfering with the tumor's blood supply. Anti-vascular endothelial growth factors (VEGF) are being tested in clinical trials.
Prostate cancer vaccines. Several types of vaccines that boost the body's immune response to prostate cancer cells are now being tested in clinical research trials.
Many options are available to treat prostate cancer. The treatment that will work best depends on several factors. These include your overall health status, age and the grade and stage of the prostate cancer when it is first diagnosed.
Take the time to research your treatment options. Get a second opinion before making a final decision. The most common treatment options for prostate cancer include watchful waiting, surgery, radiation and hormone therapy.
Watchful waiting
Since prostate cancer often grows slowly, older men over age 70 who have the disease may not need treatment. Your physician may suggest taking a wait-and-see attitude. This course of treatment will involve periodic examinations and testing to determine if the cancer has become more aggressive. If it does, active treatment can then be initiated.
Surgical treatments
Surgical treatments are used when the goal is to remove the cancer. A radical prostatectomy involves the removal of the entire prostate gland and surrounding tissue. This operation is performed only if the cancer is confined to the prostate gland itself. The surgery involves making an incision into the abdomen to gain access to the prostate gland. A urinary catheter will be in place after surgery so that urine can be drained from the body. The catheter is left in place for a few weeks. Once it is removed, there may be problems with dribbling and incontinence. This usually improves over time and can sometimes be corrected with medication or other procedures. Impotence or the inability to sustain an erection may result after radical prostate surgery due to impairment of the nerves that control erection. This condition may be temporary or, in some cases, permanent. Discuss these issues with your doctor before consenting to this type of treatment. A nerve-sparing operation, which saves the nerves that control the ability to have an erection, may reduce this risk of impotence.
Transurethral resection of the prostate (TURP) is another surgical option that may be used for men who are not candidates for radical prostate surgery. During this procedure, an instrument is inserted through the urethra and into the prostate where tissue is removed through cauterization. No incision is needed, and a catheter will be left in place for a few days until any urinary bleeding resolves. Incontinence and impotence are not generally associated with a TURP but do occur. The surgery, however, will not cure the patient since the prostate gland is not removed.
Cryosurgery
Cryosurgery is a relatively new treatment for prostate cancer that involves killing the cancer cells through freezing by rods inserted in the prostate.
Radiation therapy
Two types of radiation treatments can be used to treat prostate cancer. They involve external beam radiation, which is similar to getting an X-ray. Treatments, given on a daily basis, last several minutes, and the entire course of therapy may take six or seven weeks to complete. New technology is more exact, using CT scan localization called three dimensional conformal radiation therapy, which offers a 3-D computerized image.
Internal radiation uses radioactive seeds placed directly into the prostate gland. The pellets emit radiation for a few months and then are no longer active.
Radiation therapy does have side effects. Many patients complain of fatigue during the treatments. Others report gastrointestinal symptoms like diarrhea and nausea. Some patients may have difficulty with urination and maintaining erections.
Hormone therapy
Since prostate cancer is dependent upon the male hormone testosterone to grow, reducing the amount of testosterone can cause the tumor to shrink or grow more slowly. Testosterone levels can be reduced through surgery to remove the testicles (orchiectomy), since most testosterone is manufactured here. Hormone pills can also be given to reduce testosterone levels.
Hormone therapy is not a cure for prostate cancer but rather a way to slow its growth. Shots of Lupron® (leuprolide) or Zoledex® (goserelin) (LH-RH agonists) can block the pituitary gland from producing gonadal (testicular) growth stimulating hormones such as testosterone. Hormone treatments may have side effects. They can cause infertility, decreased libido, hot flashes, impotence and osteoporosis (thinning of the bones).
Chemotherapy
The administration of cancer-fighting drugs that kill cancer cells within the body is used only in cases of advanced prostate cancer when the disease has already spread to other organs. The goal of therapy is to reduce pain and hinder the tumor's growth. Recent studies have shown improved survival for patients with metastatic prostate cancer using Taxotere® (docetaxel).
What can I expect following treatment for prostate cancer?
After you complete your initial treatment for prostate cancer, your physician will continue to monitor you closely. You will need to have regular medical examinations that will include screening tests to check for return of the cancer, including the PSA (prostate specific antigen) blood test. If recurrent prostate cancer is found, treatment will depend on what options were chosen originally.
Are there any new developments in prostate cancer research?
HPC1 gene. Scientists have only recently discovered a gene called HPC1 that they hope will soon give additional information about the inherited risk of prostate cancer. One day there may be tests available to identify men at high risk of developing prostate cancer. Early screening procedures could then be implemented.
Angiogenesis. New drugs are being tested that may be able to halt the spread of prostate cancer by interfering with the tumor's blood supply. Anti-vascular endothelial growth factors (VEGF) are being tested in clinical trials.
Prostate cancer vaccines. Several types of vaccines that boost the body's immune response to prostate cancer cells are now being tested in clinical research trials.
Prostate Cancer
What is the prostate?
The prostate gland is a walnut-shaped organ below the bladder that encircles the urethra, which is the passage for urine. Part of the male genital tract, the prostate secretes the fluid and chemical nutrients necessary for sperm cells to survive in semen.
What is prostate cancer?
Prostate cancer is the most often diagnosed cancer in men and the second leading cause of cancer death. Although more cases of prostate cancer are found now than in past decades, most are discovered early enough to assure complete cure. The improved survival rate is in part because of the prostate specific antigen (PSA) lab test and ongoing efforts to screen men as part of routine check-ups.
The prostate gland is a walnut-shaped organ below the bladder that encircles the urethra, which is the passage for urine. Part of the male genital tract, the prostate secretes the fluid and chemical nutrients necessary for sperm cells to survive in semen.
What is prostate cancer?
Prostate cancer is the most often diagnosed cancer in men and the second leading cause of cancer death. Although more cases of prostate cancer are found now than in past decades, most are discovered early enough to assure complete cure. The improved survival rate is in part because of the prostate specific antigen (PSA) lab test and ongoing efforts to screen men as part of routine check-ups.
Sunday, July 29, 2007
Common Sexually Transmitted Diseases (HPV and genital warts )
Human papillomavirus (HPV), among the most common causes of STDs in the world, refers to not one, but 60 viruses. Some cause different types of warts. Many are found on feet, hands or other parts of the body, and some live in the genital area and are spread through genital contact. Although some forms of HPV virus cause cervical and other genital cancers, according to Planned Parenthood, the HPVs that cause genital warts do not seem to be directly associated with these cancers. However, women should have regular Pap smears so that pre-cancerous conditions can be treated.
Genital warts are very contagious. About two thirds of people who have sexual contact with a partner with genital warts develop them within three months. In women, genital warts can occur on the outside and inside of the vagina, on the cervix, or around the anus. In men, genital warts are less common, but occur on the tip of the penis, on the shaft of the penis, on the scrotum or around the anus. Rarely, genital warts can develop in the mouth or throat of a person who has had oral sexual contact with an infected person.
Genital warts often occur in clusters and can be very tiny or can spread into large masses. Left untreated, genital warts often disappear. In other cases, they eventually may develop into a fleshy, raised growth with a cauliflower-like appearance. There is no way to predict whether the warts will grow or disappear. If you suspect you have genital warts, you should see a health care provider.
Prevention: People should stop all sexual contact as soon as they know or think they have genital warts and seek treatment immediately to avoid spreading them. However, symptoms are not always visible. It is uncertain whether condoms protect you from this particular STD.
How you get HPV and genital warts: Sexual contact with an infected person
Symptoms: Sometimes none ;Firm, rough warts, sometimes flat, sometimes clustered;Irritation, burning and itching;Foul smell;Painful intercourse;Increased vaginal discharge
Diagnosis: Genital examination; microscopic analysis of tissue samples; Pap tests
Treatment:Removal through freezing, burning or laser treatment; Topical creams; Injection of antiviral drugs
Genital warts are very contagious. About two thirds of people who have sexual contact with a partner with genital warts develop them within three months. In women, genital warts can occur on the outside and inside of the vagina, on the cervix, or around the anus. In men, genital warts are less common, but occur on the tip of the penis, on the shaft of the penis, on the scrotum or around the anus. Rarely, genital warts can develop in the mouth or throat of a person who has had oral sexual contact with an infected person.
Genital warts often occur in clusters and can be very tiny or can spread into large masses. Left untreated, genital warts often disappear. In other cases, they eventually may develop into a fleshy, raised growth with a cauliflower-like appearance. There is no way to predict whether the warts will grow or disappear. If you suspect you have genital warts, you should see a health care provider.
Prevention: People should stop all sexual contact as soon as they know or think they have genital warts and seek treatment immediately to avoid spreading them. However, symptoms are not always visible. It is uncertain whether condoms protect you from this particular STD.
How you get HPV and genital warts: Sexual contact with an infected person
Symptoms: Sometimes none ;Firm, rough warts, sometimes flat, sometimes clustered;Irritation, burning and itching;Foul smell;Painful intercourse;Increased vaginal discharge
Diagnosis: Genital examination; microscopic analysis of tissue samples; Pap tests
Treatment:Removal through freezing, burning or laser treatment; Topical creams; Injection of antiviral drugs
HIV/AIDS (overview)
Human immunodeficiency virus (HIV) causes acquired immune deficiency syndrome (AIDS), which is deadly if left untreated. An HIV infection damages the immune system, your body's defense against disease and infection. A person can die from "opportunistic" infections from bacteria, viruses and other types of microscopic organisms that are usually harmless to healthy people. Because the immune system is damaged, the body of someone with this condition cannot defend itself well. AIDS is the final stage of HIV infection, when opportunistic infections occur because of a greatly weakened immune system.
Several types of white cells work to protect you. One type - called the lymphocytes - includes B cells and T cells. The B cells produce antibodies (CD4 cells) that destroy organisms invading the body. T cells help regulate the production of these antibodies. Two types of T cells are helper cells and suppressor cells. Helper cells help create antibodies and so-called cell-mediated immunity that also assist in the defense against certain infections. Suppressor cells stop or suppress immune reactions. As these helper cells are destroyed, the immune system fails and AIDS develops.
In the United States, more than half a million people have died from AIDS, and about 35,000 people are infected annually. Nearly 300,000 are living with AIDS.
Prognosis
Since 1996, the introduction of powerful antiretroviral therapies has dramatically decreased the number of people who develop AIDS. Before better therapies and medical treatments existed to take care of complications, it was thought people could live an average of 10 years after HIV infection.
Early detection of HIV infection can extend your life if you are treated with antiretroviral therapy, but to date, this infection cannot be cured. These medications must be taken for life.
Several types of white cells work to protect you. One type - called the lymphocytes - includes B cells and T cells. The B cells produce antibodies (CD4 cells) that destroy organisms invading the body. T cells help regulate the production of these antibodies. Two types of T cells are helper cells and suppressor cells. Helper cells help create antibodies and so-called cell-mediated immunity that also assist in the defense against certain infections. Suppressor cells stop or suppress immune reactions. As these helper cells are destroyed, the immune system fails and AIDS develops.
In the United States, more than half a million people have died from AIDS, and about 35,000 people are infected annually. Nearly 300,000 are living with AIDS.
Prognosis
Since 1996, the introduction of powerful antiretroviral therapies has dramatically decreased the number of people who develop AIDS. Before better therapies and medical treatments existed to take care of complications, it was thought people could live an average of 10 years after HIV infection.
Early detection of HIV infection can extend your life if you are treated with antiretroviral therapy, but to date, this infection cannot be cured. These medications must be taken for life.
Wednesday, July 25, 2007
Common Sexually Transmitted Diseases (Herpes )
Herpes can take two forms: fever blisters on the mouth or face (oral herpes, or HSV-type 1), or those appearing in the genital area (genital herpes, or HSV-type 2). Both forms are spread from skin-to-skin contact, either to the mouth or genital area. Often, people who have herpes don't have symptoms, but others have outbreaks of blisters or ulcers. Herpes infection is life-long, but outbreaks can be suppressed with medication.
Herpes is contagious just before an outbreak of blisters, when the skin may itch or tingle. The disease is most contagious when the sores are open and least contagious when the skin is normal. Outbreaks last about two weeks, but afterwards, the virus remains in the body. It can become active and cause an outbreak again at any time. Some people never experience more than one outbreak while others have frequent outbreaks.
Although no cure exists for herpes, over the course of a few years, outbreaks tend to become less frequent, usually ending almost entirely within five or six years.
Transmission of herpes from mother to baby during delivery can have grave consequences. However, infection is less likely to occur during a herpes recurrence than an initial episode.
Prevention: Frequently, people experience warning signs before an outbreak, when herpes is most contagious. These include a tingling, burning or itching sensation. That's a signal to avoid sexual contact of any kind until the outbreak is over and all signs of sores and scabs have disappeared. Between outbreaks, condoms can help reduce the spread of herpes between asymptomatic people.
How you get herpes: Skin-to-skin contact with an infected person who may or may not exhibit symptoms, including kissing or any form of sexual contact.
Symptoms: Blisters or open sores ;Pain;Itching,Flu-like symptoms during first episodes.
Diagnosis: Fluid is taken from sores and tested in the laboratory
Treatment:Cannot be cured; symptoms may be suppressed or relieved with medication
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Herpes is contagious just before an outbreak of blisters, when the skin may itch or tingle. The disease is most contagious when the sores are open and least contagious when the skin is normal. Outbreaks last about two weeks, but afterwards, the virus remains in the body. It can become active and cause an outbreak again at any time. Some people never experience more than one outbreak while others have frequent outbreaks.
Although no cure exists for herpes, over the course of a few years, outbreaks tend to become less frequent, usually ending almost entirely within five or six years.
Transmission of herpes from mother to baby during delivery can have grave consequences. However, infection is less likely to occur during a herpes recurrence than an initial episode.
Prevention: Frequently, people experience warning signs before an outbreak, when herpes is most contagious. These include a tingling, burning or itching sensation. That's a signal to avoid sexual contact of any kind until the outbreak is over and all signs of sores and scabs have disappeared. Between outbreaks, condoms can help reduce the spread of herpes between asymptomatic people.
How you get herpes: Skin-to-skin contact with an infected person who may or may not exhibit symptoms, including kissing or any form of sexual contact.
Symptoms: Blisters or open sores ;Pain;Itching,Flu-like symptoms during first episodes.
Diagnosis: Fluid is taken from sores and tested in the laboratory
Treatment:Cannot be cured; symptoms may be suppressed or relieved with medication
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Tuesday, July 24, 2007
Common Sexually Transmitted Diseases(Chlamydia)
It's called the silent STD. Chlamydia is the most common bacterial sexually transmitted disease in the United States, with about 4 million new cases reported each year. There are usually no early symptoms of Chlamydia, which, in part, explains the high incidence of the disease. Chlamydia can cause infertility in both men and women. The disease can be cured with antibiotics.
Chlamydia occurs four times more often than gonorrhea. A pregnant woman may pass the infection to her baby during delivery, causing infection of the eyes or possibly pneumonia.
Prevention: Many doctors recommend everyone who has had more than one sex partner, especially women 25 and younger, be tested for Chlamydia infection regularly, even if they have no symptoms. Using condoms or diaphragms during sexual intercourse may help reduce the transmission of Chlamydia.
How you get Chlamydia:Unprotected vaginal, oral or anal sex with an infected partner.
Symptoms: Frequently none ,Genital discharge;Bleeding between periods;Low-grade fever;Painful urination or intercourse;Inflamed or itchy rectum;Conjunctivitis
Diagnosis:Laboratory testing of genital secretions or urine sample.
Treatment:Antibiotics
Chlamydia occurs four times more often than gonorrhea. A pregnant woman may pass the infection to her baby during delivery, causing infection of the eyes or possibly pneumonia.
Prevention: Many doctors recommend everyone who has had more than one sex partner, especially women 25 and younger, be tested for Chlamydia infection regularly, even if they have no symptoms. Using condoms or diaphragms during sexual intercourse may help reduce the transmission of Chlamydia.
How you get Chlamydia:Unprotected vaginal, oral or anal sex with an infected partner.
Symptoms: Frequently none ,Genital discharge;Bleeding between periods;Low-grade fever;Painful urination or intercourse;Inflamed or itchy rectum;Conjunctivitis
Diagnosis:Laboratory testing of genital secretions or urine sample.
Treatment:Antibiotics
Monday, July 23, 2007
Benign Prostatic Hyperplasia
The prostate normally enlarges in men as they age. However, not all men develop symptoms of BPH.
A derivative of the male hormone testosterone called dihydrotestosterone (DHT), which is concentrated in the prostate, may be associated with growth of the prostate. As men age, their bodies don't produce as much testosterone. However, DHT is still produced. Because the DHT is concentrated in the prostate, this may encourage cell growth.
Another theory talks about the proportions of estrogen and testosterone in a man's body. As men age, there is a higher proportion of estrogen compared to testosterone. Animal studies have suggested that higher amounts of estrogen within the prostate gland may trigger substances that promote prostate cell growth.
It is not known what makes the prostate more or less susceptible to hormonal effects. Age, nationality or a family history of BPH may account for this susceptibility to some extent.
A derivative of the male hormone testosterone called dihydrotestosterone (DHT), which is concentrated in the prostate, may be associated with growth of the prostate. As men age, their bodies don't produce as much testosterone. However, DHT is still produced. Because the DHT is concentrated in the prostate, this may encourage cell growth.
Another theory talks about the proportions of estrogen and testosterone in a man's body. As men age, there is a higher proportion of estrogen compared to testosterone. Animal studies have suggested that higher amounts of estrogen within the prostate gland may trigger substances that promote prostate cell growth.
It is not known what makes the prostate more or less susceptible to hormonal effects. Age, nationality or a family history of BPH may account for this susceptibility to some extent.
Benign Prostatic Hyperplasia
Prostate gland
The prostate is a walnut-sized gland that makes up part of the male reproductive system. The prostate gland makes some of the milky fluid (semen) that carries sperm. It is located in front of the rectum and just below the bladder, where urine is stored. The prostate gland surrounds the urethra, the canal through which urine passes out of the body. During a man's orgasm (sexual climax), muscles squeeze the prostate's fluid into the urethra. Sperm, which are made in the testicles, also go into the urethra during orgasm. The milky fluid carries the sperm through the penis during orgasm.
Prostate gland enlargement
It is common for the prostate gland to enlarge as men age. The enlargement of the prostate gland is called benign prostatic hyperplasia, or BPH. Most enlargements are NOT due to cancer.
Though the prostate continues to grow during most of a man's life, the enlargement doesn't usually cause problems before age 40. However, more than half of men in their 60s and as many as 90 percent in their 70s and 80s have some symptoms of BPH, according to the National Institutes of Health.
As the prostate enlarges, the layer of tissue surrounding it stops it from expanding, causing the prostate to press against the urethra. This causes the wall of the bladder to thicken and become irritated. The bladder begins to contract even when it contains small amounts of urine, causing more frequent urination.
Eventually, the bladder weakens and loses the ability to empty itself completely, so urine remains in the bladder. The narrowing of the urethra makes the urine stream weak and leads to straining in an attempt to empty the bladder. The most common cause of difficulty with urination in men is enlargement of the prostate gland.
Symptoms May Include:
Difficulty starting to urinate
Weak urination stream
Interruption of urination stream
Dribbling at end of urination
Sensation of incomplete bladder emptying
Urge to urinate frequently, especially at night
Deep discomfort in lower abdomen
Incontinence
The prostate is a walnut-sized gland that makes up part of the male reproductive system. The prostate gland makes some of the milky fluid (semen) that carries sperm. It is located in front of the rectum and just below the bladder, where urine is stored. The prostate gland surrounds the urethra, the canal through which urine passes out of the body. During a man's orgasm (sexual climax), muscles squeeze the prostate's fluid into the urethra. Sperm, which are made in the testicles, also go into the urethra during orgasm. The milky fluid carries the sperm through the penis during orgasm.
Prostate gland enlargement
It is common for the prostate gland to enlarge as men age. The enlargement of the prostate gland is called benign prostatic hyperplasia, or BPH. Most enlargements are NOT due to cancer.
Though the prostate continues to grow during most of a man's life, the enlargement doesn't usually cause problems before age 40. However, more than half of men in their 60s and as many as 90 percent in their 70s and 80s have some symptoms of BPH, according to the National Institutes of Health.
As the prostate enlarges, the layer of tissue surrounding it stops it from expanding, causing the prostate to press against the urethra. This causes the wall of the bladder to thicken and become irritated. The bladder begins to contract even when it contains small amounts of urine, causing more frequent urination.
Eventually, the bladder weakens and loses the ability to empty itself completely, so urine remains in the bladder. The narrowing of the urethra makes the urine stream weak and leads to straining in an attempt to empty the bladder. The most common cause of difficulty with urination in men is enlargement of the prostate gland.
Symptoms May Include:
Difficulty starting to urinate
Weak urination stream
Interruption of urination stream
Dribbling at end of urination
Sensation of incomplete bladder emptying
Urge to urinate frequently, especially at night
Deep discomfort in lower abdomen
Incontinence
Sunday, July 22, 2007
Can a Vitamin Cut Prostate Cancer Risk
Simply being male and getting older puts you at risk for prostate cancer. But could you cut that risk if you took common vitamins and minerals?
Preliminary evidence suggests that you can. Vitamin E and the mineral selenium have been shown in some small studies to cut the risk of prostate cancer between 30 percent and 60 percent. Now, researchers are giving the vitamin and mineral a second look in the largest-ever prostate cancer prevention trial.
More than a few good men
The National Cancer Institute (NCI) and a network of researchers known as the Southwest Oncology Group (SWOG) are looking for "quite a few good men" to participate in the Selenium and Vitamin E Cancer Prevention Trial, or SELECT, according to Charles A. Coltman Jr., M.D., chairman of SWOG and director of the San Antonio Cancer Institute in Texas.
The study will include a total of 32,400 healthy men of all races and ethnic backgrounds who are age 55 and older (50 and older for African-American men).
"Previous research with vitamin E and selenium - in studies that focused on other kinds of cancer - suggested that these nutrients might prevent prostate cancer. SELECT is focused on prostate cancer, and when the study is finished, we will know for sure whether these supplements can prevent the disease," Coltman says.
During the next 12 years, doctors in medical centers across the United States, Puerto Rico and Canada will follow participating patients to see whether those taking vitamin E and/or selenium develop cancer less frequently than those taking placebos.
The American Cancer Society (ACS) says men who participate in the study not only have a chance to prevent prostate cancer for themselves but also may help their sons and grandsons live free from the disease.
Prostate cancer is the most common cancer among men, except for skin cancer. In 2006, about 234,460 new cases of prostate cancer will be diagnosed in the United States. Though slow-growing and easily treated in the early stage, prostate cancer, unfortunately, usually isn't diagnosed until the disease has advanced. The ACS estimates more about 27,350 will die from the disease in 2006.
Three-fourths of men who are diagnosed are 65 and older. Your risk for developing prostate cancer is higher if your father or brother has had the disease. It is much more common in African-American men than in Caucasian men and less common in Asians and Native Americans.
Early evidence encouraging
The SELECT study is an outgrowth of two studies. In 1996 selenium was studied for the prevention of non-melanoma skin cancer in 1,000 men and women. It wasn't found effective for skin cancer prevention, but investigators did report a 60 percent decrease in the incidence of prostate cancer. Then, in a lung cancer study published in 1998, more than 29,000 male smokers took beta-carotene and vitamin E to determine if these supplements have any lung cancer prevention benefit. Again, the study revealed an unexpected result. Neither of the nutrients showed any effect against lung cancer, but those who took vitamin E had 32 percent less prostate cancer than the general population.
Vitamin E and selenium are antioxidants, which are nutrients believed to help control cell damage that can lead to cancer. Both vitamin E and selenium are normally found in water and food in small amounts. Selenium is especially found in meat, seafood and Brazil nuts. Good sources of vitamin E are vegetables, vegetable oil, nuts and egg yolks.
Because the earlier studies are promising, the Prostate Cancer Research Institute (PCRI) recommends both vitamin E and selenium as part of a diet to reduce the risk of prostate cancer. Seidmon recommends that men start taking vitamin E and selenium supplements by age 40. PCRI is a nonprofit educational and research center in Los Angeles founded by two medical oncologists.
How much to take
If you want to take these nutrients as part of your own health regimen, the daily amounts recommended in the study, 200 micrograms of selenium and 400 International Units of vitamin E are more than what's typically found in a multivitamin.
Some evidence suggests that a diet high in animal fat may increase your risk of prostate cancer and a diet high in fruits and vegetables may decrease the risk. A few studies have suggested that having a vasectomy might increase a man's risk for prostate cancer. However, the NCI says this finding has not been supported.
When should you get screened?
All men with a family history of prostate cancer or breast cancer on their mother's side are advised to have a yearly PSA blood test and digital rectal testing starting between ages 35 to 40, according to the PCRI.
In a digital rectal exam, the doctor uses his finger to feel if the prostate is enlarged, a sign that a cancerous tumor may be present. Also, the PSA test can detect levels of prostate specific antigen, or PSA, which is a hormone in the blood. Normally, the PSA level is between zero and four.
If the annual test shows that the PSA level is increasing, then further evaluation is recommended. Even if it's within the normal range, when the number is increasing, there should be additional testing with an ultrasound and biopsy, the PCRI urges.
If there's no family history of prostate or breast cancer, the PCRI recommends annual testing for all men starting at age 40. The American Urologic Association has a more specific recommendation; it suggests annual testing at age 40 for all black males and age 50 for all white males.
"We know that between 10 percent and 20 percent of all men have occult-stage cancer," says E. James Seidmon, M.D., professor of urology and diagnostic imaging at Temple University Medical School in Philadelphia. In occult-stage cancer, the cancerous cells are present, but there are no symptoms.
"The cancer is there and it's growing, but because it's so slow-growing, we have to wait until we see the rise in PSA to find it. The majority of diagnoses are being made this way," states Seidmon.
Preliminary evidence suggests that you can. Vitamin E and the mineral selenium have been shown in some small studies to cut the risk of prostate cancer between 30 percent and 60 percent. Now, researchers are giving the vitamin and mineral a second look in the largest-ever prostate cancer prevention trial.
More than a few good men
The National Cancer Institute (NCI) and a network of researchers known as the Southwest Oncology Group (SWOG) are looking for "quite a few good men" to participate in the Selenium and Vitamin E Cancer Prevention Trial, or SELECT, according to Charles A. Coltman Jr., M.D., chairman of SWOG and director of the San Antonio Cancer Institute in Texas.
The study will include a total of 32,400 healthy men of all races and ethnic backgrounds who are age 55 and older (50 and older for African-American men).
"Previous research with vitamin E and selenium - in studies that focused on other kinds of cancer - suggested that these nutrients might prevent prostate cancer. SELECT is focused on prostate cancer, and when the study is finished, we will know for sure whether these supplements can prevent the disease," Coltman says.
During the next 12 years, doctors in medical centers across the United States, Puerto Rico and Canada will follow participating patients to see whether those taking vitamin E and/or selenium develop cancer less frequently than those taking placebos.
The American Cancer Society (ACS) says men who participate in the study not only have a chance to prevent prostate cancer for themselves but also may help their sons and grandsons live free from the disease.
Prostate cancer is the most common cancer among men, except for skin cancer. In 2006, about 234,460 new cases of prostate cancer will be diagnosed in the United States. Though slow-growing and easily treated in the early stage, prostate cancer, unfortunately, usually isn't diagnosed until the disease has advanced. The ACS estimates more about 27,350 will die from the disease in 2006.
Three-fourths of men who are diagnosed are 65 and older. Your risk for developing prostate cancer is higher if your father or brother has had the disease. It is much more common in African-American men than in Caucasian men and less common in Asians and Native Americans.
Early evidence encouraging
The SELECT study is an outgrowth of two studies. In 1996 selenium was studied for the prevention of non-melanoma skin cancer in 1,000 men and women. It wasn't found effective for skin cancer prevention, but investigators did report a 60 percent decrease in the incidence of prostate cancer. Then, in a lung cancer study published in 1998, more than 29,000 male smokers took beta-carotene and vitamin E to determine if these supplements have any lung cancer prevention benefit. Again, the study revealed an unexpected result. Neither of the nutrients showed any effect against lung cancer, but those who took vitamin E had 32 percent less prostate cancer than the general population.
Vitamin E and selenium are antioxidants, which are nutrients believed to help control cell damage that can lead to cancer. Both vitamin E and selenium are normally found in water and food in small amounts. Selenium is especially found in meat, seafood and Brazil nuts. Good sources of vitamin E are vegetables, vegetable oil, nuts and egg yolks.
Because the earlier studies are promising, the Prostate Cancer Research Institute (PCRI) recommends both vitamin E and selenium as part of a diet to reduce the risk of prostate cancer. Seidmon recommends that men start taking vitamin E and selenium supplements by age 40. PCRI is a nonprofit educational and research center in Los Angeles founded by two medical oncologists.
How much to take
If you want to take these nutrients as part of your own health regimen, the daily amounts recommended in the study, 200 micrograms of selenium and 400 International Units of vitamin E are more than what's typically found in a multivitamin.
Some evidence suggests that a diet high in animal fat may increase your risk of prostate cancer and a diet high in fruits and vegetables may decrease the risk. A few studies have suggested that having a vasectomy might increase a man's risk for prostate cancer. However, the NCI says this finding has not been supported.
When should you get screened?
All men with a family history of prostate cancer or breast cancer on their mother's side are advised to have a yearly PSA blood test and digital rectal testing starting between ages 35 to 40, according to the PCRI.
In a digital rectal exam, the doctor uses his finger to feel if the prostate is enlarged, a sign that a cancerous tumor may be present. Also, the PSA test can detect levels of prostate specific antigen, or PSA, which is a hormone in the blood. Normally, the PSA level is between zero and four.
If the annual test shows that the PSA level is increasing, then further evaluation is recommended. Even if it's within the normal range, when the number is increasing, there should be additional testing with an ultrasound and biopsy, the PCRI urges.
If there's no family history of prostate or breast cancer, the PCRI recommends annual testing for all men starting at age 40. The American Urologic Association has a more specific recommendation; it suggests annual testing at age 40 for all black males and age 50 for all white males.
"We know that between 10 percent and 20 percent of all men have occult-stage cancer," says E. James Seidmon, M.D., professor of urology and diagnostic imaging at Temple University Medical School in Philadelphia. In occult-stage cancer, the cancerous cells are present, but there are no symptoms.
"The cancer is there and it's growing, but because it's so slow-growing, we have to wait until we see the rise in PSA to find it. The majority of diagnoses are being made this way," states Seidmon.
Know Your Prostate Cancer Risks
Most men are offered prostate screening starting at age 50. However, some would benefit from screening at an earlier age. African-Americans, for instance, are nearly twice as likely to develop prostate cancer. A family history of prostate cancer is also a major risk factor. About 10 percent of cases are associated with family history, where the heredity pattern for prostate cancer is between father and son or two brothers. Research implicates specific gene mutations in these families that lead to prostate cancer susceptibility.
Earlier screening
If your brother or father had prostate cancer, your own risk doubles and continues to rise with the number of relatives having the disease. If they developed prostate cancer at a young age, the risk is still higher. For men without any relatives with prostate cancer, screening tests (DRE and PSA) should begin at age 50. For those with a first-degree relative (father or brother) with prostate cancer, doctors offer screening at 45.
The importance of family history
If your father or brother has prostate cancer, you are more likely to develop the disease six or seven years earlier than men without any history of prostate cancer in the family.
The more relatives, the higher the risk. Three or more relatives increase the risk by 35 to 45 percent.
If your father was diagnosed younger than age 60, your risk is about 20 percent greater than the general population.
The prostate gland and screening
The prostate gland sits below the bladder, in front of the rectum and surrounds the urethra (urine tube) that leads into the penis. The prostate turns the semen into a favorable environment for sperm. The screening tests take advantage of the prostate's relatively easy access and one of its products, prostate specific antigen (PSA).
Digital rectal exam (DRE)
The back portion of the prostate is close to the rectum. So a doctor can feel the surface of the prostate by inserting a gloved finger and feeling for lumps or any irregularities on the surface.
Prostate specific antigen (PSA) test
The PSA is a blood test for a protein unique to the prostate gland. Most PSA exists in semen, but a small portion of it is circulating in the blood. If greater than a count of 4, the risk for prostate cancer increases. The "normal" for each man depends on several factors, including age and size of the prostate. An elevated PSA level may also indicate that there is an infection of the prostate (prostatitis). Doctors don't make any decisions based on a single PSA reading, but observe changes in PSA over time. The results help the doctor decide whether a biopsy is necessary to see if there is cancer within the gland.
What you can do
Know your prostate family history: Who has or had prostate cancer? At what age were they diagnosed?
Don't panic if you find out there is a family history of prostate cancer. Remember: prostate cancer grows very slowly compared to other kinds of cancer. Thus, if diagnosed early enough prostate cancer can be cured.
Get screened. The American Cancer Society recommends that men with a family history of prostate cancer be screened at age 45 (usually screening starts at 50).
Earlier screening
If your brother or father had prostate cancer, your own risk doubles and continues to rise with the number of relatives having the disease. If they developed prostate cancer at a young age, the risk is still higher. For men without any relatives with prostate cancer, screening tests (DRE and PSA) should begin at age 50. For those with a first-degree relative (father or brother) with prostate cancer, doctors offer screening at 45.
The importance of family history
If your father or brother has prostate cancer, you are more likely to develop the disease six or seven years earlier than men without any history of prostate cancer in the family.
The more relatives, the higher the risk. Three or more relatives increase the risk by 35 to 45 percent.
If your father was diagnosed younger than age 60, your risk is about 20 percent greater than the general population.
The prostate gland and screening
The prostate gland sits below the bladder, in front of the rectum and surrounds the urethra (urine tube) that leads into the penis. The prostate turns the semen into a favorable environment for sperm. The screening tests take advantage of the prostate's relatively easy access and one of its products, prostate specific antigen (PSA).
Digital rectal exam (DRE)
The back portion of the prostate is close to the rectum. So a doctor can feel the surface of the prostate by inserting a gloved finger and feeling for lumps or any irregularities on the surface.
Prostate specific antigen (PSA) test
The PSA is a blood test for a protein unique to the prostate gland. Most PSA exists in semen, but a small portion of it is circulating in the blood. If greater than a count of 4, the risk for prostate cancer increases. The "normal" for each man depends on several factors, including age and size of the prostate. An elevated PSA level may also indicate that there is an infection of the prostate (prostatitis). Doctors don't make any decisions based on a single PSA reading, but observe changes in PSA over time. The results help the doctor decide whether a biopsy is necessary to see if there is cancer within the gland.
What you can do
Know your prostate family history: Who has or had prostate cancer? At what age were they diagnosed?
Don't panic if you find out there is a family history of prostate cancer. Remember: prostate cancer grows very slowly compared to other kinds of cancer. Thus, if diagnosed early enough prostate cancer can be cured.
Get screened. The American Cancer Society recommends that men with a family history of prostate cancer be screened at age 45 (usually screening starts at 50).
Prostatitis
Prostatitis is an inflammation of the prostate gland, a common condition in adult males. Often caused by infection, prostatitis may develop rapidly (acute) or slowly (chronic).
Description
Prostatitis may be the symptom-producing disease of the genitourinary tract for which men most often seek medical help. About 40% of visits to a specialist in genitourinary problems (urologist) are for prostatitis. Forms of prostate inflammation include acute and chronic bacterial prostatitis and inflammation not caused by bacterial infection. A painful condition called prostatodynia, which may be caused by abnormal nerves or muscles in the region, is also thought to be a form of prostatitis. The chronic bacterial form is sometimes experienced by men whose sex partners have a bacterial infection of the vagina, making this a sexually transmitted disease. Other cases occur when small stones form within the prostate and become infected. Sometimes infection is caused by poor hygiene, surgical procedures, or even swimming in polluted water.
The sexually transmitted disease gonorrhea may sometimes cause prostatitis, and tuberculosis may spread to the prostate. Parasites and fungi may infect the prostate gland. Some men whose prostatitis is not caused by any microorganism have microscopic collections of cells called granulomas in their prostate tissue. Whether viruses also may cause prostatitis is debatable.
Causes and symptoms
However the inflammation may begin, it causes blockages in the tiny glands within the prostate so that secretions build up, and the prostate swells. In acute cases, this swelling can occur very suddenly and cause considerable pain. When prostatitis develops gradually, trouble with the flow of urine may be the first symptom. Small stones may form, because the body attempts to neutralize bacteria by coating them with calcium. These stones may become infected themselves and make the condition worse.
Symptoms and signs that are typically experienced by men with prostatitis include:
Difficulties in urinating. Most urinary problems are caused when the swollen prostate blocks the tube that carries urine from the bladder to the outside of the body (urethra). Patients feel the need to urinate more often than usual, often urgently. Urination is sometimes painful. It is hard to start the flow of urine and difficult to totally empty the bladder. Patients wake up at night to urinate. The stream may be weak or split. Dribbling after attempts to urinate may leave embarrassing wet spots on clothing. In severe prostatitis blood or sand-like particles (small calcium collections) may be passed in the urine.
Pain. Besides pain when urinating, caused by prostate swelling, stimulation of nerves in the prostate gland may cause pain in the penis, one or both testicles, the lower stomach, the low back, and the area between the scrotum and the anus (perineum). Some patients experience pain during or after ejaculation, whenever they sit down or walk, or during bowel movements.
Sex and fertility. The pain of prostatitis can make it impossible to enjoy sex. Men with prostatitis may be troubled by early release of sperm (premature ejaculation). Occasionally there is blood in the semen. Some of the drugs prescribed to ease the flow of the urine can dampen the desire to have sex. Because the normal prostate secretions make up part of the semen, prostatitis may lower fertility by severely lowering the number of sperm and making them less mobile.
Psychological problems. A man with prostatitis who feels that nothing can be done and he "just has to live with it" may experience serious depression. Low sexual desire certainly contributes to depression.
A person with acute prostatitis may suddenly develop fever and chills, along with rapidly developing urinary symptoms and pain in the perineum or low back. This state is a medical emergency that demands immediate medical help.
Most often the symptoms and physical findings are enough to form a diagnosis of prostatitis. When the examiner inserts a finger in the rectum, the swollen prostate can be felt; it may be extremely tender when probed. Squeezing the gland slightly will produce a few drops of fluid that may be cultured to learn whether bacteria are present. The fluid typically contains a large number of white blood cells, especially the cells used to fight off infection (macrophages). Note: too much pressure on the prostate can force bacteria into the blood and cause a serious general infection. Many patients with chronic bacterial prostatitis also have recurring urinary tract infections (diagnosed by examining and culturing urine samples). These infections can be an important clue to the diagnosis. If doubt remains, the urologist may insert a special instrument called a cystoscope through the penis to directly view the prostate from inside and see whether it looks inflamed.
Acute prostatitis is first treated with antibiotics. Even though it may be difficult for drugs to actually get into the inflamed prostate, most patients do quickly get better. If intravenous antibiotics are needed or the bladder is retaining urine, a hospital stay may be necessary. Broad-spectrum antibiotics that work against most bacteria are used first. At the same time tests are done with samples of prostatic fluid to determine which bacterium is causing the infection, so that drugs can be prescribed to fight the specific germ. In chronic cases, the best results are obtained with a combination of the antibiotics trimethoprim and sulfamethoxazole. Oral antibiotics should be given for one to three months; longer, if necessary. If a fungus or some other organism is causing infection, special drugs are available. If chronic prostatitis continues despite all medical efforts and is seriously affecting the patient's life, the prostate may be removed surgically.
Nonbacterial prostatitis requires other measures to relieve urinary symptoms. These measures include drugs that fight inflammation (steroids or nonsteroids) and a type of drug called an alpha-blocker that reduces muscle tension. Reduced muscle tension eases urine flow, allowing the bladder to empty. A narrowed urethra may be widened by placing a collapsed balloon at the site of obstruction and expanding it. This procedure is called balloon dilation. The effects of such dilation are usually temporary. Some physicians believe that stress is an important factor in prostatitis, and therefore prescribe diazepam (Valium) or another tranquilizer. The type of prostatitis known as prostatodynia is usually treated with a combination of muscle relaxing drugs, heat, special exercises, and sometimes a tranquilizer.
There are a number of "tips" for relieving symptoms of prostatitis. They are especially helpful early on, before antibiotics have a chance to cure infection, or for patients with chronic or non-bacterial prostatitis:
Hot sitz baths. Exposing the perineum to very hot water for 20 minutes or longer often relieves pain.
Ice. When heat does not help, ice packs, or simply placing a small ice cube in the rectum, may relieve pain for hours.
Water. A patient who has to urinate very often may want to cut back on his fluid intake but this will cause dehydration and increase the risk of bladder infection. Instead, it is best to drink plenty of water.
Diet. Most doctors recommend cutting out--or cutting down on--caffeine (as in coffee or tea), alcohol, and spicy or acid foods. Constipation should be avoided because large, hard bowel movements may press on the swollen prostate and cause great pain. Bran cereals and whole-grain breads are helpful.
Exercise. It is especially important for patients with chronic prostatitis to keep up their activity level. Simply walking often will help (unless walking happens to make the pain worse).
Frequent ejaculation. Ejaculating two or three times a week often is recommended, especially when taking antibiotics.
A treatment popularized in the Philippines is called "prostate drainage." At regular intervals, a finger is inserted into the rectum, to exert pressure on the prostate at the same time that an antibiotic treatment is given. Acupuncture and Chinese herbal medicine also can be effective in treating prostatitis. Nutritional supplements that support the prostate, including zinc, omega-3 fatty acids, several amino acids, and anti-inflammatory nutrients and herbs, can help reduce pain and promote healing. Western herbal medicine recommends saw palmetto (Serenoa repens) to support the prostate gland. Hot and cold contrast sitz baths can help reduce inflammation.
Most patients with acute bacterial prostatitis are cured if they receive proper antibiotic treatment. Every effort should be made to get a cure at the acute stage because chronic prostatitis can be much more difficult to eliminate. If the acute illness is not controlled, complications such as a localized infection (prostatic abscess), kidney infection, or infection of the blood (septicemia) may develop. When chronic prostatitis cannot be cured, it still is possible to keep urinary symptoms under control and keep the patient active by using low doses of antibiotics and other measures. If a man with any form of prostatitis develops serious psychological problems, he should be referred to a psychiatric specialist.
Potential sources of infection should be avoided. Good perineal hygiene should be maintained and sex should be avoided when one's partner has an active bacterial vaginal infection. If the kidneys, bladder, or other genitourinary organs are infected, prompt treatment may prevent the development of prostatitis. By far the best way of preventing chronic prostatitis is to treat an initial acute episode promptly and effectively.
Description
Prostatitis may be the symptom-producing disease of the genitourinary tract for which men most often seek medical help. About 40% of visits to a specialist in genitourinary problems (urologist) are for prostatitis. Forms of prostate inflammation include acute and chronic bacterial prostatitis and inflammation not caused by bacterial infection. A painful condition called prostatodynia, which may be caused by abnormal nerves or muscles in the region, is also thought to be a form of prostatitis. The chronic bacterial form is sometimes experienced by men whose sex partners have a bacterial infection of the vagina, making this a sexually transmitted disease. Other cases occur when small stones form within the prostate and become infected. Sometimes infection is caused by poor hygiene, surgical procedures, or even swimming in polluted water.
The sexually transmitted disease gonorrhea may sometimes cause prostatitis, and tuberculosis may spread to the prostate. Parasites and fungi may infect the prostate gland. Some men whose prostatitis is not caused by any microorganism have microscopic collections of cells called granulomas in their prostate tissue. Whether viruses also may cause prostatitis is debatable.
Causes and symptoms
However the inflammation may begin, it causes blockages in the tiny glands within the prostate so that secretions build up, and the prostate swells. In acute cases, this swelling can occur very suddenly and cause considerable pain. When prostatitis develops gradually, trouble with the flow of urine may be the first symptom. Small stones may form, because the body attempts to neutralize bacteria by coating them with calcium. These stones may become infected themselves and make the condition worse.
Symptoms and signs that are typically experienced by men with prostatitis include:
Difficulties in urinating. Most urinary problems are caused when the swollen prostate blocks the tube that carries urine from the bladder to the outside of the body (urethra). Patients feel the need to urinate more often than usual, often urgently. Urination is sometimes painful. It is hard to start the flow of urine and difficult to totally empty the bladder. Patients wake up at night to urinate. The stream may be weak or split. Dribbling after attempts to urinate may leave embarrassing wet spots on clothing. In severe prostatitis blood or sand-like particles (small calcium collections) may be passed in the urine.
Pain. Besides pain when urinating, caused by prostate swelling, stimulation of nerves in the prostate gland may cause pain in the penis, one or both testicles, the lower stomach, the low back, and the area between the scrotum and the anus (perineum). Some patients experience pain during or after ejaculation, whenever they sit down or walk, or during bowel movements.
Sex and fertility. The pain of prostatitis can make it impossible to enjoy sex. Men with prostatitis may be troubled by early release of sperm (premature ejaculation). Occasionally there is blood in the semen. Some of the drugs prescribed to ease the flow of the urine can dampen the desire to have sex. Because the normal prostate secretions make up part of the semen, prostatitis may lower fertility by severely lowering the number of sperm and making them less mobile.
Psychological problems. A man with prostatitis who feels that nothing can be done and he "just has to live with it" may experience serious depression. Low sexual desire certainly contributes to depression.
A person with acute prostatitis may suddenly develop fever and chills, along with rapidly developing urinary symptoms and pain in the perineum or low back. This state is a medical emergency that demands immediate medical help.
Most often the symptoms and physical findings are enough to form a diagnosis of prostatitis. When the examiner inserts a finger in the rectum, the swollen prostate can be felt; it may be extremely tender when probed. Squeezing the gland slightly will produce a few drops of fluid that may be cultured to learn whether bacteria are present. The fluid typically contains a large number of white blood cells, especially the cells used to fight off infection (macrophages). Note: too much pressure on the prostate can force bacteria into the blood and cause a serious general infection. Many patients with chronic bacterial prostatitis also have recurring urinary tract infections (diagnosed by examining and culturing urine samples). These infections can be an important clue to the diagnosis. If doubt remains, the urologist may insert a special instrument called a cystoscope through the penis to directly view the prostate from inside and see whether it looks inflamed.
Acute prostatitis is first treated with antibiotics. Even though it may be difficult for drugs to actually get into the inflamed prostate, most patients do quickly get better. If intravenous antibiotics are needed or the bladder is retaining urine, a hospital stay may be necessary. Broad-spectrum antibiotics that work against most bacteria are used first. At the same time tests are done with samples of prostatic fluid to determine which bacterium is causing the infection, so that drugs can be prescribed to fight the specific germ. In chronic cases, the best results are obtained with a combination of the antibiotics trimethoprim and sulfamethoxazole. Oral antibiotics should be given for one to three months; longer, if necessary. If a fungus or some other organism is causing infection, special drugs are available. If chronic prostatitis continues despite all medical efforts and is seriously affecting the patient's life, the prostate may be removed surgically.
Nonbacterial prostatitis requires other measures to relieve urinary symptoms. These measures include drugs that fight inflammation (steroids or nonsteroids) and a type of drug called an alpha-blocker that reduces muscle tension. Reduced muscle tension eases urine flow, allowing the bladder to empty. A narrowed urethra may be widened by placing a collapsed balloon at the site of obstruction and expanding it. This procedure is called balloon dilation. The effects of such dilation are usually temporary. Some physicians believe that stress is an important factor in prostatitis, and therefore prescribe diazepam (Valium) or another tranquilizer. The type of prostatitis known as prostatodynia is usually treated with a combination of muscle relaxing drugs, heat, special exercises, and sometimes a tranquilizer.
There are a number of "tips" for relieving symptoms of prostatitis. They are especially helpful early on, before antibiotics have a chance to cure infection, or for patients with chronic or non-bacterial prostatitis:
Hot sitz baths. Exposing the perineum to very hot water for 20 minutes or longer often relieves pain.
Ice. When heat does not help, ice packs, or simply placing a small ice cube in the rectum, may relieve pain for hours.
Water. A patient who has to urinate very often may want to cut back on his fluid intake but this will cause dehydration and increase the risk of bladder infection. Instead, it is best to drink plenty of water.
Diet. Most doctors recommend cutting out--or cutting down on--caffeine (as in coffee or tea), alcohol, and spicy or acid foods. Constipation should be avoided because large, hard bowel movements may press on the swollen prostate and cause great pain. Bran cereals and whole-grain breads are helpful.
Exercise. It is especially important for patients with chronic prostatitis to keep up their activity level. Simply walking often will help (unless walking happens to make the pain worse).
Frequent ejaculation. Ejaculating two or three times a week often is recommended, especially when taking antibiotics.
A treatment popularized in the Philippines is called "prostate drainage." At regular intervals, a finger is inserted into the rectum, to exert pressure on the prostate at the same time that an antibiotic treatment is given. Acupuncture and Chinese herbal medicine also can be effective in treating prostatitis. Nutritional supplements that support the prostate, including zinc, omega-3 fatty acids, several amino acids, and anti-inflammatory nutrients and herbs, can help reduce pain and promote healing. Western herbal medicine recommends saw palmetto (Serenoa repens) to support the prostate gland. Hot and cold contrast sitz baths can help reduce inflammation.
Most patients with acute bacterial prostatitis are cured if they receive proper antibiotic treatment. Every effort should be made to get a cure at the acute stage because chronic prostatitis can be much more difficult to eliminate. If the acute illness is not controlled, complications such as a localized infection (prostatic abscess), kidney infection, or infection of the blood (septicemia) may develop. When chronic prostatitis cannot be cured, it still is possible to keep urinary symptoms under control and keep the patient active by using low doses of antibiotics and other measures. If a man with any form of prostatitis develops serious psychological problems, he should be referred to a psychiatric specialist.
Potential sources of infection should be avoided. Good perineal hygiene should be maintained and sex should be avoided when one's partner has an active bacterial vaginal infection. If the kidneys, bladder, or other genitourinary organs are infected, prompt treatment may prevent the development of prostatitis. By far the best way of preventing chronic prostatitis is to treat an initial acute episode promptly and effectively.
Friday, July 20, 2007
Premature Ejaculation (general view)
Premature ejaculation occurs when male sexual climax (orgasm) occurs before a man wishes it or too quickly during intercourse to satisfy his partner. Premature ejaculation is the most commonly reported sexual complaint of men and couples. The highest number of complaints is among teenage, young adult, and sexually inexperienced males. Increased risk is associated with sexual inexperience and lack of knowledge of normal male sexual responses. There are several reasons why a man may ejaculate prematurely. For some men, the cause is due to an innate reflex or psychological predisposition of the nervous system. Sometimes it can be caused by certain drugs, such as non-prescription cold medications. Psychological factors, such as stress, fear, or guilt can also play a role. Examples of psychological factors include guilt that the sexual activity is wrong or sinful, fear of getting caught, or stress from problems at work or home.
In general, symptoms are when a male reaches climax in less than two minutes or when it occurs before the male or couple want it to occur. There are no tests used to diagnose premature ejaculation. It is usually determined by the male involved based on his belief that he reached orgasm too quickly. General guidelines for premature ejaculation is if it occurs in two minutes or less, or prior to about 15 thrusts during sexual intercourse. In 1966, William H. Masters and Virginia E. Johnson published Human Sexual Response, in which they broke the first ground in approaching this topic from a new perspective. Their method was devised by Dr. James Seman and has been modified subsequently by Dr. Helen Singer Kaplan and others.
A competent and orthodox sex therapist will spend much more time focusing on the personal than the sexual relationship between the two people who come for treatment. Without emotional intimacy, sexual relations are superficial and sexual problems such as premature ejaculation are not always overcome. With that foremost in mind, a careful plan is outlined that requires dedication, patience, and commitment by both partners. It necessarily begins by prohibiting intercourse for an extended period of time-at least a week, often a month. This is very important to the man because "performance anxiety" is the greatest enemy of performance. If he knows he cannot have intercourse he is able to relax and focus on the exercises. The first stage is called "sensate focus" and involves his concentration on the process of sexual arousal and climax. He should learn to recognize each step in the process, most particularly the moment just before the "point of no return." Ideally, this stage of treatment requires the man's partner to be devoted to his sensations. In order to regain equality, he should in turn spend separate time stimulating and pleasing his mate, without intercourse.
At this point the techniques diverge. The original "squeeze technique" requires that the partner become expert at squeezing the head of the penis at intervals to prevent orgasm. The modified procedure, described by Dr. Ruth Westheimer, calls upon the man to instruct the partner when to stop stimulating him to give him a chance to draw back. A series of stages follows, each offering greater stimulation as the couple gains greater control over his arousal. This whole process has been called "outercourse." After a period of weeks, they will have together retrained his response and gained satisfactory control over it. In addition, they will each have learned much about the other's unique sexuality and ways to increase each other's pleasure.
With either technique, the emphasis is on the mutual goal of satisfactory sexual relations for both partners.
However, the 1990s ushered in a new era in the treatment of premature ejaculation when physicians discovered that certain antidepression drugs had a side effect of delaying ejaculation. Clinical studies have shown that a class of antidepressants called selective seratonin reuptake inhibitors (SSRIs) can be very effective in prolonging the time to ejaculation. The individual drugs and the average amount of time they delay ejaculation are fluoxetine (Prozac), one to two minutes with doses of 20-40 milligrams per day (mg/day) and eight minutes with 60 mg/day; paroxetine (Paxil), three to 10 minutes with doses of 20-40 mg/day; and sertraline (Zoloft), two to five minutes with doses of 50-200 mg/day.
There are several alternative products, usually found in health food and nutrition stores, designed to be sprayed or rubbed on the penis to delay ejaculation. Although the products promise results, there are no valid clinical studies to support the claims. A device called a testicular restraint, sold through erotic mail-order magazines, sometimes helps men delay ejaculation. The Velcro-like device restrains the testicles from their natural tendency to move during sex. Testicular movement can cause premature ejaculation.
The "squeeze technique" has elicited a 95% success rate, whereby the patient is able to control ejaculation. Treatment with SSRIs is effective in 85-90% of cases. However, the effectiveness begins to decrease after five weeks of daily administration. Although more studies are needed, this suggests the SSRIs are more effective when used on an as-needed basis.
The best prevention is obtaining adequate information on normal sexual responses of males before having sex. It is also helpful to have sex in a comfortable, relaxed, private setting, free of guilt, stress, and fear.
In general, symptoms are when a male reaches climax in less than two minutes or when it occurs before the male or couple want it to occur. There are no tests used to diagnose premature ejaculation. It is usually determined by the male involved based on his belief that he reached orgasm too quickly. General guidelines for premature ejaculation is if it occurs in two minutes or less, or prior to about 15 thrusts during sexual intercourse. In 1966, William H. Masters and Virginia E. Johnson published Human Sexual Response, in which they broke the first ground in approaching this topic from a new perspective. Their method was devised by Dr. James Seman and has been modified subsequently by Dr. Helen Singer Kaplan and others.
A competent and orthodox sex therapist will spend much more time focusing on the personal than the sexual relationship between the two people who come for treatment. Without emotional intimacy, sexual relations are superficial and sexual problems such as premature ejaculation are not always overcome. With that foremost in mind, a careful plan is outlined that requires dedication, patience, and commitment by both partners. It necessarily begins by prohibiting intercourse for an extended period of time-at least a week, often a month. This is very important to the man because "performance anxiety" is the greatest enemy of performance. If he knows he cannot have intercourse he is able to relax and focus on the exercises. The first stage is called "sensate focus" and involves his concentration on the process of sexual arousal and climax. He should learn to recognize each step in the process, most particularly the moment just before the "point of no return." Ideally, this stage of treatment requires the man's partner to be devoted to his sensations. In order to regain equality, he should in turn spend separate time stimulating and pleasing his mate, without intercourse.
At this point the techniques diverge. The original "squeeze technique" requires that the partner become expert at squeezing the head of the penis at intervals to prevent orgasm. The modified procedure, described by Dr. Ruth Westheimer, calls upon the man to instruct the partner when to stop stimulating him to give him a chance to draw back. A series of stages follows, each offering greater stimulation as the couple gains greater control over his arousal. This whole process has been called "outercourse." After a period of weeks, they will have together retrained his response and gained satisfactory control over it. In addition, they will each have learned much about the other's unique sexuality and ways to increase each other's pleasure.
With either technique, the emphasis is on the mutual goal of satisfactory sexual relations for both partners.
However, the 1990s ushered in a new era in the treatment of premature ejaculation when physicians discovered that certain antidepression drugs had a side effect of delaying ejaculation. Clinical studies have shown that a class of antidepressants called selective seratonin reuptake inhibitors (SSRIs) can be very effective in prolonging the time to ejaculation. The individual drugs and the average amount of time they delay ejaculation are fluoxetine (Prozac), one to two minutes with doses of 20-40 milligrams per day (mg/day) and eight minutes with 60 mg/day; paroxetine (Paxil), three to 10 minutes with doses of 20-40 mg/day; and sertraline (Zoloft), two to five minutes with doses of 50-200 mg/day.
There are several alternative products, usually found in health food and nutrition stores, designed to be sprayed or rubbed on the penis to delay ejaculation. Although the products promise results, there are no valid clinical studies to support the claims. A device called a testicular restraint, sold through erotic mail-order magazines, sometimes helps men delay ejaculation. The Velcro-like device restrains the testicles from their natural tendency to move during sex. Testicular movement can cause premature ejaculation.
The "squeeze technique" has elicited a 95% success rate, whereby the patient is able to control ejaculation. Treatment with SSRIs is effective in 85-90% of cases. However, the effectiveness begins to decrease after five weeks of daily administration. Although more studies are needed, this suggests the SSRIs are more effective when used on an as-needed basis.
The best prevention is obtaining adequate information on normal sexual responses of males before having sex. It is also helpful to have sex in a comfortable, relaxed, private setting, free of guilt, stress, and fear.
Wednesday, July 18, 2007
Erectile Dysfunction and Hypertension
Recent analyses suggest that about 67-68% of men with hypertension have some degree of erectile dysfunction (ED). With about 25 million men in the US with hypertension, substantial numbers of hypertension-related ED exist that tend to be of a more severe nature than the general population. Men with ED are also more likely to have hypertension. Thiazide diuretic and beta-blocker therapy may contribute to ED. Phosphodiesterase-5 (PDE5) inhibitors are effective therapy in men with ED owing to hypertension who are taking antihypertensive medicines including those on multiple antihypertensive medicines. The addition of PDE5 inhibitors to usual common antihypertensive medicines (diuretics, beta blockers, calcium blockers, angiotensin converting enzyme inhibitors and angiotensin receptor blockers) results in either no or small additive reductions in blood pressure (BP) and no increase in serious clinical adverse events. There are however precautions regarding the use of PDE5 inhibitors in patients taking alpha blockers for either hypertension or benign prostatic hypertrophy, as some patients may develop orthostatic hypotension. Organic nitrates remain an absolute contraindication for PDE5 inhibitors because synergistic and symptomatic reductions in BP may occur in some patients with this drug combination.
Tuesday, July 17, 2007
Erectile Dysfunction.4
Oral pharmacotherapy is very effective and safe method for Erectile Dysfunction, especially the advent of phosphodiesterase type 5 inhibitors: sildenafil, tadanafil and vardenafil. Sildenafil was the first PDE5 inhibitor and >20 million men have been treated in the 6yr since its launch. It is effective after 30-60 mi from administration. Tadanafil is effective from 30min after administeration, but its peak efficacy is expected in about 2 h. efficacy is maintained for up to 36h. Its efficacy is not influenced by food. Vardenafil is effective after 30min from administeration. Its effect is reduced by a heavy fatty meal.
Thursday, July 12, 2007
Life Science.Stem Cell
The study of stem cell stem from the research of mouse embryonal carcinoma cell. Stem cell is a kind of cell that can self-renewal and can be differentiated into other kinds of cells. Nowadays, the main content of the study of stem cell is the separation, identification, self-renewal and the plasticity of stem cell. Clinic application is the ultimate aim of scientist, but it seems that more research is still required before final goal can be completed.
Wednesday, July 11, 2007
Erectile dysfunction.2
Erectile Dysfunction is ver common in aging man. Statistical data from MMAS (Massachusetts Male Aging Study)shows the overall probability of complete impotence tripled from 5% in subjects 40 years old to 15% in subjects 70 years old. There are also other studies which support this view. The reason why the prevalence of ED in aging man is so high is associated with many factors. Treatment for ED in aging man is recommended by EAU with two-steps therapy, which will be discussed in detail in the later.
Prostate Cancer
Prostate Cancer is the most frequently diagnosed cancer in men, especially in west countries. Thanks to the discovery of Prostate Specific Antigen, which serves as a mark of prostate cancer, the disease could be found in an early-stage. prostatectomy or radiation, the most common treatments for localized disease, have a high rate of cure. Treatment for advanced disease includes hormonal treatment (also known as androgen deprivation therapy) and chemotherapy. A number of new, promising agents are currently in development. Especially findings of susceptive genes could bring more revolutions
Tuesday, July 10, 2007
Premature Ejaculation.1
Definitely, Premature Ejaculation is another disease that embarrassed men. In fact, the concensus of the difinition of Premature Ejaculation have not reached by far. The etiology of Premature Ejaculation is complexed, including psychogenic and organic. It seems that psychogenic factors account for the most of Premature Ejaculation. The recent advances, including the etiology,epidemiology and treatment, about Premature Ejaculation will be elaborated in the later.
Erectile dysfunction.1
the difinition of erectile dysfunction is that: The inability to achieve and maintain an erectile sufficient to permit satisfactory sexual intercourse. many studies show that erectile dysfunction is associated with many diseases bisides itself organic and psychogenic causes, including hypertension, diabetes and depression. oberviously , the application of PDE5 inhibitor successfully improves the life of ED patients ,but its etiology still remains to be futher studied.
Monday, July 9, 2007
Men.Sex.1
Weekly, I make cavernosography for patients who were diagnosed with Erectile Dysfunction. Most of them were found problems with penile arteriovenous fistula. Sometimes, The results confused me since nothing could be found to be responsible for the arteriovenous fistula. Recent study of epidemiology shows organic reason is mainly the etilogy of Erectile Dysfunction(ED is classified with psychogenic, organic and mixed)
On The Road Of Medicine
Medicine is a kind of science that is profound and elaborate. Although it is an extremely old science, There are still a lot which are waitting for us to explore. miserably and mirthfully, I became a medical student in order to satisfy my parents desire. On the road of medicine, I find a truth: the more you learn, the less you know.
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