13th Sep 2013, 03:41 PM #471
Re: Health Bulletin
Middle-aged men, too, can blame estrogen for that waistline
It is the scourge of many a middle-aged man: he starts getting a pot belly, using lighter weights at the gym and somehow just doesn't have the sexual desire of his younger years.
The obvious culprit is testosterone, since men gradually make less of the male sex hormone as years go by. But a surprising new answer is emerging, one that doctors say could reinvigorate the study of how men's bodies age. Estrogen, the female sex hormone, turns out to play a much bigger role in men's bodies than previously thought, and falling levels contribute to their expanding waistlines just as they do in women's.
The discovery of the role of estrogen in men is "a major advance," said Dr Peter J Snyder, a professor of medicine at the University of Pennsylvania, who is leading a big new research project on hormone therapy for men 65 and over. Until recently, testosterone deficiency was considered nearly the sole reason that men undergo the familiar physical complaints of midlife.
The new frontier of research involves figuring out which hormone does what in men, and how body functions are affected at different hormone levels. While dwindling testosterone levels are to blame for middle-aged men's smaller muscles, falling levels of estrogen regulate fat accumulation, according to a study published Wednesday in The New England Journal of Medicine, which provided the most conclusive evidence to date that estrogen is a major factor in male midlife woes. And both hormones are needed for libido.
"Some of the symptoms routinely attributed to testosterone deficiency are actually partially or almost exclusively caused by the decline in estrogens," said Dr Joel Finkelstein, an endocrinologist at Harvard Medical School and the study's lead author, in a news release on Wednesday.
His study is only the start of what many hope will be a new understanding of testosterone and estrogen in men. Dr Snyder is leading another study, the Testosterone Trial, which measures levels of both hormones and asks whether testosterone treatment can make older men with low testosterone levels more youthful — by letting them walk more quickly, feel more vigorous, improve their sexual functioning and their memories, and strengthen their bones. Smaller studies have been promising but unreliable, and estrogen has not been factored in.
"We had ignored this hormone in men, but we are studying it now," said Dr Alvin M Matsumoto, a testosterone and geriatrics researcher at the University of Washington School of Medicine and the VA Puget Sound Health Care System, who is a Testosterone Trial researcher. "We are just starting out on this road."
Both men and women make estrogen out of testosterone, and men make so much that they end up with at least twice as much estrogen as postmenopausal women. As levels of both hormones decline with age, the body changes. But until now, researchers have focused almost exclusively on how estrogen affects women and how testosterone affects men.
Dr Finkelstein's study provides a new road map of the function of each hormone and its behavior at various levels. It suggests that different symptoms kick in at different levels of testosterone deficiency. Testosterone, he found, is the chief regulator of muscle tone and lean body mass, but it takes less than was thought to maintain muscle. For a young man, 550 nanograms of testosterone per decilitre of blood serum is the average level, and doctors have generally considered levels below 300 nanograms so low they might require treatment, typically with testosterone gels.
But Dr Finkelstein's study found that muscle strength and size turn out to be unaffected until testosterone levels drop very low, below 200 nanograms. Fat accumulation, however, kicks in at higher testosterone levels: at 300 to 350 nanograms of testosterone, estrogen levels sink low enough that middle-aged spread begins.
As for sexual desire and performance, both require estrogen and testosterone, and they increase steadily as those hormone levels rise. Researchers say it is too early to make many specific recommendations, but no one is suggesting that men take estrogen, because high doses cause feminine features like enlarged breasts.
Although doctors prescribe testosterone gels for men whose levels fall below 300 nanograms per deciliter, that cutoff point is arbitrary, and there is no clinical rationale for it, Dr Finkelstein said. Often men take the hormone to treat complaints like fatigue, depression or loss of sexual desire, which may or may not be from low levels of testosterone. The data suggest that men with levels around 300 nanograms who complain of sexual problems may want to try testosterone, but those who complain of flagging muscle strength should not blame testosterone deficiency, Dr Finkelstein said. But, he added, "symptoms of low testosterone tend to be quite vague."
Today, millions of men are using testosterone gels, fueling a nearly $2 billion market.
For their study, Dr Finkelstein and his colleagues recruited 400 men aged 20 to 50 who agreed to have their testosterone production turned off for 16 weeks. Half then received varying amounts of testosterone, while the other half also got a drug that shuts off estrogen synthesis so the researchers could assess the effects of having testosterone but not estrogen.
It turned out to be surprisingly easy to recruit subjects, Dr Finkelstein said. One, Ben Iverson, joined in part for the $1,000 subjects were paid. "That, to me, was enticing," he said. He was a 28-year-old Harvard graduate student at the time and is now an assistant professor of finance at Northwestern University.
Although Mr Iverson's wife looked askance at the injections to block testosterone production, Mr Iverson ended up getting enough testosterone in the gel he was assigned to use. The worst were the testosterone-suppressing injections, which required him to use a huge needle in his abdomen once a month, he said.
He found out when the study ended that he was in a group that got enough testosterone to keep his levels in a normal range. "I literally did not notice any difference at all," Mr Iverson recalled.
The worst symptoms were in men whose estrogen production was shut down — they got intense hot flashes.
Now Dr Finkelstein is repeating the study with older men. The Testosterone Trial is looking at them too.
For that study, Dr Snyder and his colleagues recruited nearly 800 men aged 65 and older who have low testosterone levels. The men take either a placebo or enough testosterone to bring their level to between 400 and 800. Investigators are assessing walking speed, sexual functioning, vitality, memory, red-blood-cell count, bones and coronary arteries. The yearlong study will be completed next year.
Next, researchers said, they want to do a large study like one conducted with thousands of women in 2002 that asked about long-term risks and benefits of hormone therapy. Does testosterone therapy lead, for example, to more prostate cancer? Does it prevent heart attacks?
"We still don't know the answers to the clinical questions," Dr Matsumoto said. "Does it prevent things that are really important?"
13th Sep 2013, 03:51 PM #472
Re: Health Bulletin
Tobacco inflicts huge damage on the health of of 1.5 million India's people a year
Tobacco inflicts huge damage on the health of India's people and could be clocking up a death toll of 1.5 million a year by 2020 if more users are not persuaded to kick the habit, an international report said on Thursday.
Despite having signed up to a global treaty on tobacco control and having numerous anti-tobacco and smoke-free laws, India is failing to implement them effectively, leaving its people vulnerable to addiction and ill health, according to the report by the International Tobacco Control Project (ITCP).
"Compared with many countries around the world, India has been proactive in introducing tobacco control legislation since 2003," said Geoffrey Fong, a professor of psychology at Canada's University of Waterloo and a co-author of the report.
"However ... the legislation currently in place is not delivering the desired results - in terms of dissuading tobacco use and encouraging quitting."
As a result, India, with a population of 1.2 billion, currently has around 275 million tobacco users, the report said.
Harm from tobacco accounts for nearly half of all cancers among males and a quarter of all cancers among females there, as well as being a major cause of heart and lung diseases.
"The tobacco epidemic in India requires urgent attention," the report said, adding that by 2020, tobacco consumption will account for more than 1.5 million Indian deaths a year.
Worldwide, the number of deaths caused by tobacco is expected to rise from around 6 million a year now to more than 8 million by 2030, according to the World Health Organisation.
The ITCP India Survey conducted face to face interviews with 8,000 tobacco users and 2,400 non-users across four Indian states - Bihar, Madhya Pradesh, Maharashtra and West Bengal.
So-called smokeless tobacco - including chewing products such as gutkha, zarda, paan masal and khaini - is the most common form of tobacco use in India, with many poorer people and women preferring these over smoking cigarettes or bindis - small, cheap, locally-made cigarettes.
According to the Global Adult Tobacco Survey, 26 percent of adults in India consume smokeless tobacco - 33 percent of men and 18.4 percent of women. Smokeless tobacco can cause oral and other cancers, as well as other mouth diseases and heart disease.
Among several striking findings in the ITCP report was that, while many smokers and tobacco users said they knew of the health risks, only a small proportion said they would like to quit.
Up to 94 percent of smokers and up to the same proportion of smokeless users in the survey said they had no plans to give up.
Set against this, the report also found that up to 81 percent of smokers and up to 87 percent of smokeless tobacco users expressed regret for taking up the habit, and more than 90 percent of tobacco users and non-users in all four states had negative views on smoking and tobacco.
The report said that, while India has been a regional leader in enacting tobacco control legislation over the past 10 years, the laws are poorly enforced, regulations covering smoke-free zones are patchy, and tobacco remains relatively cheap.
Fong said the low percentage of people wanting to quit meant deaths from tobacco use were destined to stay high.
"If there is any single indicator of the urgent need for continued and strengthened efforts for strong, evidence-based tobacco control in India - this is it."
13th Sep 2013, 03:52 PM #473
Re: Health Bulletin
What makes cholera toxin so deadly
Researchers have identified an underlying biochemical mechanism that helps make cholera toxin so deadly, often resulting in life-threating diarrhea.
Two groups of scientists at the University of California, San Diego, worked on fruit flies, mice and cultured human intestinal cells to study cholera toxin, produced by the highly infectious bacterium Vibrio cholerae.
They discovered the toxin exerts some of its devastating effects by reducing the delivery of proteins to molecular junctions that normally act like Velcro to hold intestinal cells together in the outer lining of the gut.
The UC San Diego researchers found that cholera toxin acts by two entirely distinct, but cooperating mechanisms to produce diarrhea. In addition to increasing the efflux of chloride ions through a protein channel called CFTR, it weakens cell junctions to allow a rapid outflow of counterbalancing sodium ions and water between the cells.
The scientists showed that many of the effects of the cholera toxin on the gut could be reversed by genetic manipulations that bolster the delivery of proteins to these junctions.
Understanding this novel mechanism of cholera action could also have important implications for other disorders of intestinal barrier function such as Crohn's disease, colitis and celiac disease.
The study is published in the journal Cell Host and Microbe.
14th Sep 2013, 12:51 PM #474
Re: Health Bulletin
Steroid jabs ups risk of HIV infection
: Nearly 10 percent men injecting themselves with anabolic steroids or tanning drugs could have been exposed to HIV, hepatitis B or hepatitis C, a new poll has shown.
According to the Public Health England (PHE), the number of people using image and performance-enhancing drugs has risen over the past 20 years.
Co-author Jim McVeigh, from the Centre for Public Health at Liverpool John Moores University, said that people injecting themselves with anabolic steroids and associated drugs are the biggest client group at many needle and syringe programs in the UK.
PHE and Liverpool John Moores University researchers questioned 395 men who used such type of drugs and found that one in 18 people had been exposed to hepatitis C, one in 11 had been exposed to hepatitis B and one in 65 had HIV, News.com.au reported.
Overall, 10 percent men were exposed to one or more of the blood-borne viruses.
The study has been published in BMJ Open.
14th Sep 2013, 12:52 PM #475
Re: Health Bulletin
A microbe may be key to eternal youth
Scientists have discovered a microbe that stays young forever by rejuvenating every time it reproduces, a finding that provides fundamental insights into the mechanisms of aging.
An international team involving researchers from the University of Bristol and the Max-Planck Institute for Molecular Cell Biology and Genetics in Germany has found that a common species of yeast microbe has evolved to stay young.
The organism could potentially serve as a model of certain non-aging types of cells in humans, researchers said. The team has shown that, unlike other species, the yeast microbe called S pombe, is immune to aging when it is reproducing and under favourable growth conditions. In general, even symmetrically diving microbes, do not split into two exactly identical halves.
Detailed investigations revealed that there are mechanisms in place that ensure that one half gets older, often defective, cell material, whereas the other half is equipped with new fully-functional material. So like humans microbes, in a sense, produce offspring that is younger than parent.
15th Sep 2013, 12:18 PM #476
Re: Health Bulletin
Cell transplants may help treat schizophrenia
Cell transplants could be used to treat schizophrenia, scientists have found.
In a new study, researchers found that transplanting stem cells into the rat brain - into a centre called the hippocampus - restored functions that are abnormal in schizophrenia.
Cells called "interneurons" inhibit activity within brain regions, but this braking or governing function is impaired in schizophrenia.
Consequently, a group of nerve cells called the dopamine system go into overdrive. Different branches of the dopamine system are involved in cognition, movement and emotions.
"Since these cells are not functioning properly, our idea is to replace them," said study senior author Daniel Lodge, assistant professor of pharmacology in the School of Medicine at The University of Texas Health Science Center at San Antonio.
Lodge and lead author Stephanie Perez, graduate student in his laboratory, biopsied tissue from rat foetuses, isolated cells from the tissue and injected the cells into a brain centre called the hippocampus.
This centre regulates the dopamine system and plays a role in learning, memory and executive functions such as decision making. Rats treated with the transplanted cells had restored hippocampal and dopamine function.
Stem cells are able to become different types of cells, and in this case interneurons were selected.
"We put in a lot of cells and not all survived, but a significant portion did and restored hippocampal and dopamine function back to normal," Lodge said.
Unlike traditional approaches to treating schizophrenia, such as medications and deep-brain stimulation, transplantation of interneurons potentially can produce a permanent solution.
"You can essentially fix the problem. Ultimately, if this is translated to humans, we want to reprogramme a patient's own cells and use them," Lodge said.
The study is published in the journal Molecular Psychiatry.
15th Sep 2013, 12:28 PM #477
Re: Health Bulletin
An orange a day can keep cancer away
On reviewing available research on cancer prevention and the benefits of orange, scientists say orange could prove to be crucial in the prevention of cancer.
In a forthcoming review article from Nutrition and Cancer: An International Journal, a publication of Routledge, researchers reviewed available evidence that links orange juice with cancer chemoprevention, reports Science Daily.
The review article, 'Orange Juice and Cancer Chemoprevention' discusses the putative mechanisms involved in the process and the available data in terms of evidence-based medicine.
Despite its potential toxicity (if taken in excess), orange juice has many potential positive effects when it comes to cancer, particularly because it is high in anti-oxidants.
Evidence from previous studies has indicated that orange juice can reduce the risk of leukemia in children, as well as aid in chemoprevention against mammary, hepatic, and colon cancers.
"Orange juice could contribute to chemoprevention at every stage of cancer initiation and progression",the researchers explained.
15th Sep 2013, 12:46 PM #478
Re: Health Bulletin
Holy water may harm health
Holy water, which is known for its purported cleansing properties, could actually be more harmful for your health than healing, a new study has revealed.
Researchers at the Institute of Hygiene and Applied Immunology at the Medical University of Vienna tested water from 21 springs in Austria and 18 fonts in Vienna and found samples contained up to 62 million bacteria per milliliter of water, which is not safe to drink, ABC News reported.
Researchers found that 86 percent of the holy water, commonly used in baptism ceremonies and to wet congregants' lips, was infected with common bacteria found in fecal matter such as E. coli, enterococci and Campylobacter.
The water contaminated with these bacteria can lead to diarrhea, cramping, abdominal pain, and fever.
It was found that the water also contained nitrates , commonly found in fertilizer from farms.
The research also suggested that while all church and hospital chapel fonts contained bacteria, the busier the church, the higher the bacterial count.
The study is published in the Journal of Water and Health.
16th Sep 2013, 11:55 AM #479
Re: Health Bulletin
High-fat diets interrupt stomach's signals to the brain: Study
Indulging in fatty foods could destroy stomach's signals to the brain, according to a new study which gives insight why many dieters tend to regain the weight after losing it.
New University of Adelaide research has found the nerves in the stomach which signal fullness to the brain appeared to be desensitised after long-term consumption of a high-fat diet.
The findings could explain why many dieters tend to regain the weight they have lost.
PhD student Stephen Kentish investigated the impact of high-fat diets on the ability of the gut to signal its fullness, and whether those changes revert back to normal by losing weight.
Study leader associate professor Amanda Page said laboratory studies showed the stomach's nerve response does not return to normal upon a return to a normal diet.
"This means you would need to eat more food before you felt the same degree of fullness as a healthy individual," she said.
"A hormone in the body, leptin, known to regulate food intake, can also change the sensitivity of the nerves in the stomach that signal fullness.
"In normal conditions, leptin acts to stop food intake. However, in the stomach in high-fat diet induced obesity, leptin further desensitises the nerves that detect fullness."
Associate professor Page said the two mechanisms combined meant that obese people needed to eat more to feel full, which fuels their obesity cycle.
She said the results had "very strong implications for obese people, those trying to lose weight, and those who are trying to maintain their weight loss".
"Unfortunately, our results show that the nerves in the stomach remain de-sensitised to fullness after weight loss has been achieved," she said.
Associate professor Page says the researchers were not yet sure whether the effect was permanent or just long-lasting.
17th Sep 2013, 03:08 PM #480
Re: Health Bulletin
Horses and iPads help autistic kids communicate
A new study has revealed that children with autism can improve their verbal communications skills with the help of horses and iPads.
Southern Tier Alternative Therapies, Inc. (STAT), together with Tina Caswell, a clinical faculty member in Ithaca College's Department of Speech-Language Pathology and Audiology, has combined equine therapy and assistive technology through an exclusive program called Strides.
The Strides program puts children on horseback and gives each family iPads equipped with speech-generating applications.
Caswell and her team of Ithaca College graduate students provide intensive, highly customized training and ongoing support. The unique therapeutic approach has helped children reach significant breakthroughs in communication, both verbally and through effective use of the device.
Caswell said that it's the first time the children have been on horseback, the first time many of them are using iPads with speech software, and more important, the first time they've had any kind of access to self-expression.
She said that parents also told her that it's the first time they've been able to have a two-way conversation with their kids.
The researchers found that children are doing more than requesting food and toys and for the first time, they are telling narratives and sharing feelings.
Each child participating in the program is given an iPad to be used as a speech-generating device. Participants and their parents are then trained by the Strides team and the Ithaca College students and faculty to continuously update new communication opportunities on their devices.