Health Technology Research Synopsis 101st Issue Date 06 MAR 11 Compiled By Ralph Turchiano
Editors Top Five:
- 1. Is dairy colostrum the key to Olympic success?
- 2. Long-term use of osteoporosis medication associated with increased risk of atypical fractures
- 3. Scientists call for ‘swifter and sounder’ testing of chemicals
4.Old folk remedy revived: How tansy may be a treatment for herpes
- 5. Low vitamin D levels linked to allergies in kids In this issue:
1. Chemical compounds in trees can fight deadly staph infections in humans
2. Cell phone use may have effect on brain activity, but health consequences unknown
- 3. Long-term use of osteoporosis medication associated with increased risk of atypical fractures
- 4. Old folk remedy revived: How tansy may be a treatment for herpes
- 5. Higher vitamin D intake needed to reduce cancer risk
- 6. Microbes help children to breathe easily
- 7. Is dairy colostrum the key to Olympic success?
8. Low vitamin D levels linked to allergies in kids
- 9. AP IMPACT: Past medical testing on humans revealed
- 10. Experts propose global guidelines for safe use and production of Kava
- 11. Fish oil fights weight loss due to chemotherapy
- 12. Study links vitamin D to lung cancer survival
- 13. Study shows pine bark naturally improves kidney function in patients with metabolic syndrome
- 14. Potassium levels possible key to racial disparity in Type 2 diabetes
- 15. Polishing the apple’s popular image as a healthy food
- 16. Non-steroidal anti-inflammatory drugs linked to increased risk of erectile dysfunction
- 17. Scientists call for ‘swifter and sounder’ testing of chemicals
- 18. Sperm quality and counts worsening in Finland
- 19. Study finds MRSA danger in gyms may be exaggerated
- 20. Solving a traditional Chinese medicine mystery
- 21. Can you predict your mate will cheat by their voice?
Chemical compounds in trees can fight deadly staph infections in humans
COLUMBIA, Mo. – Most people would never suspect that a “trash tree,” one with little economic value and often removed by farmers due to its ability to destroy farmland, could be the key to fighting a deadly bacterium. Now, a University of Missouri researcher has found an antibiotic in the Eastern Red Cedar tree that is effective against methicillin-resistant Staphylococcus aureus (MRSA), a “superbug” that is resistant to most medications.
“I wanted to find a use for a tree species that is considered a nuisance,” said Chung-Ho Lin, research assistant professor in the MU Center for Agroforestry at the College of Agriculture, Food and Natural Resources. “This discovery could help people fight the bacteria as well as give farmers another cash crop.”
MRSA is an evolving bacterium that is resistant to most medications. For most people, the infection is isolated to the skin. However, it can spread to vital organs causing toxic shock syndrome and pneumonia, especially in people with weakened immune systems. The incidence of disease caused by MRSA bacteria is increasing worldwide. Thirty years ago, MRSA accounted for 2 percent of all staph infections. By 2003, that number had climbed to 64 percent. In 2005, more than 94,000 people developed life-threatening MRSA infections in the United States, according to a Centers for Disease Control report. Nearly 19,000 people died during hospital stays related to these infections.
While the Eastern Red Cedar has few commercial uses, it is present in the U.S. in large numbers and its range extends from Kansas to the eastern United States. An estimated 500 million trees grow in Missouri. Lin began his investigation by building on existing research showing the anti-bacterial potential of chemical compounds derived from the tree.
Lin, George Stewart, professor and department chair of Pathobiology in the College of Veterinary Medicine, and Brian Thompson, postdoctoral fellow in the Bond Life Sciences Center, identified, isolated and tested 17 bioactive compounds and has plans to analyze more compounds. Scientists found that a relatively small concentration of a chemical compound found in the Eastern Red Cedar– 5 micrograms per milliliter – was effective against MRSA. The team tested the compound’s effectiveness against many versions of MRSA in a test tube with promising initial results.
“We found this chemical from the cedar needles, an abundant and renewable resource that can be collected annually,” co-researcher Brian Thompson said. “Because the compound is in the needles, we don’t have to cut down the trees.”
In addition to its potential use in fighting MRSA, researchers found that some chemical compounds in the tree are able to fight and kill skin cancer cells present in mice. It may also be effective as a topical acne treatment. Stewart said the compounds are years away from commercial use, as they must go through clinical trials. The team’s research was presented recently at the International Conference on Gram-Positive Pathogens.
Public release date: 22-Feb-2011
Cell phone use may have effect on brain activity, but health consequences unknown
This release is also available in Chinese on EurekAlert! Chinese.
In a preliminary study, researchers found that 50-minute cell phone use was associated with increased brain glucose metabolism (a marker of brain activity) in the region closest to the phone antenna, but
the finding is of unknown clinical significance, according to a study in the February 23 issue of JAMA.
“The dramatic worldwide increase in use of cellular telephones has prompted concerns regarding potential harmful effects of exposure to radiofrequency-modulated electromagnetic fields (RF-EMFs). Of particular concern has been the potential carcinogenic effects from the RF-EMF emissions of cell phones. However, epidemiologic studies of the association between cell phone use and prevalence of brain tumors have been inconsistent (some, but not all, studies showed increased risk), and the issue remains unresolved,” according to background information in the article. The authors add that studies performed in humans to investigate the effects of RF-EMF exposures from cell phones have yielded variable results, highlighting the need for studies to document whether RF-EMFs from cell phone use affects brain function in humans.
Nora D. Volkow, M.D., of the National Institutes of Health, Bethesda, Md., and colleagues conducted a study to assess if cell phone exposure affected regional activity in the human brain. The randomized study, conducted between January 1 and December 31, 2009, included 47 participants. Cell phones were placed on the left and right ears and brain imaging was performed with positron emission tomography (PET) with (18F)fluorodeoxyglucose injection, used to measure brain glucose metabolism twice, once with the right cell phone activated (sound muted) for 50 minutes (“on” condition) and once with both cell phones deactivated (“off” condition). Analysis was conducted to verify the association of metabolism and estimated amplitude of radiofrequency-modulated electromagnetic waves emitted by the cell phone. The PET scans were compared to assess the effect of cell phone use on brain glucose metabolism.
The researchers found that whole-brain metabolism did not differ between the on and off conditions. However, there were significant regional effects. Metabolism in the brain region closest to the antenna (orbitofrontal cortex and temporal pole) was significantly higher (approximately 7 percent) for cell phone on than for cell phone off conditions. “The increases were significantly correlated with the estimated electromagnetic field amplitudes both for absolute metabolism and normalized metabolism,” the authors write. “This indicates that the regions expected to have the greater absorption of RF-EMFs from the cell phone exposure were the ones that showed the larger increases in glucose metabolism.”
“These results provide evidence that the human brain is sensitive to the effects of RF-EMFs from acute cell phone exposures,” the researchers write. They add that the mechanisms by which RF-EMFs could affect brain glucose metabolism are unclear.
“Concern has been raised by the possibility that RF-EMFs emitted by cell phones may induce brain cancer. … Results of this study provide evidence that acute cell phone exposure affects brain metabolic activity. However, these results provide no information as to their relevance regarding potential carcinogenic effects (or lack of such effects) from chronic cell phone use.”
“Further studies are needed to assess if these effects could have potential long-term harmful consequences,” the authors conclude.
(JAMA. 2011;305808-814. Available pre-embargo to the media at http://www.jamamedia.org) “Although the biological significance, if any, of increased glucose metabolism from acute cell phone
exposure is unknown, the results warrant further investigation. An important question is whether glucose
metabolism in the brain would be chronically increased from regular use of a wireless phone with higher radiofrequency energy than those used in the current study. Potential acute and chronic health effects need to be clarified. Much has to be done to further investigate and understand these effects.”
The editorial authors also question whether the findings of Volkow et al may be a marker of other alterations in brain function from radiofrequency emissions, such as neurotransmitter and neurochemical activities? “If so, this might have effects on other organs, leading to unwanted physiological responses. Further studies on biomarkers of functional brain changes from exposure to radiofrequency radiation are definitely warranted.”
Public release date: 22-Feb-2011
Long-term use of osteoporosis medication associated with increased risk of atypical fractures
Older women who used bisphosphonates (medications that prevent loss of bone mass) for five years or more were more likely to experience “atypical” fractures involving the femoral shaft (bone in the leg that extends from the hip to the knee) or subtrochanteric (fractures in the bone just below the hip joint), compared to women with less usage. However, the absolute risk of these “atypical” fractures was low and bisphosphonate use was associated with a reduced risk of typical osteoporotic fractures, according to a study in the February 23 issue of JAMA.
“Approximately 50 percent of women older than 50 years will sustain an osteoporosis-related fracture during their lifetime, and 1 of 5 patients with an osteoporosis-related fracture will die within 12 months. Although randomized trials have shown that treatment with bisphosphonates reduces the risk of osteoporotic fractures, concerns have recently emerged that bisphosphonate-related suppression of bone remodeling may adversely influence bone strength,” according to background information in the article. An increasing number of case reports describe women with long-term bisphosphonate therapy who develop fractures involving the subtrochanteric or shaft region of the femur, considered atypical because of their location and characteristic appearance on x-rays. The U.S. Food and Drug Administration recently announced its intent to actively monitor instances of bisphosphonate-induced atypical fractures.
Laura Y. Park-Wyllie, Pharm.D., M.Sc., of the Li Ka Shing Knowledge Institute of St. Michael’s Hospital, Toronto, Canada, and colleagues examined the association between long-term bisphosphonate use and subtrochanteric or femoral shaft fractures in a large population of postmenopausal women. The study included women ages 68 years or older from Ontario who initiated therapy with an oral bisphosphonate between April 2002 and March 2008. Cases were those hospitalized with a subtrochanteric or femoral shaft fracture and were matched to up to 5 controls with no such fracture. Study participants were followed up until March 31, 2009.
Over the study period, the researchers identified 205,466 women treated with a bisphosphonate who met inclusion criteria for the study, and within this group, 716 women were identified who sustained a subtrochanteric or femoral shaft fracture following initiation of bisphosphonate therapy, including 411 women with a subtrochanteric fracture and 305 women with a femoral shaft fracture. These cases were matched to 3,580 controls.
In the primary analysis, the researchers found that use of bisphosphonates for 5 years or longer was associated with a 2.7 times higher odds of hospitalization for subtrochanteric or femoral shaft fracture compared with transient use (less than 100 days in total) of bisphosphonates.
The secondary analysis examining the risk of typical osteoporotic fractures included 9,723 women with fractures of the femoral neck or intertrochanteric region (a section of the femur) during bisphosphonate therapy. Extended bisphosphonate use (greater than 5 years) was associated with a 24 percent reduced risk of fracture compared with transient use. Women with intermediate bisphosphonate use (3-5 years) demonstrated a similarly low risk, while a shorter duration of bisphosphonate use (100 days to 3 years) was associated with a nonsignificant reduction in the risk of such fractures.
Further analysis suggested that more than half of subtrochanteric or femoral shaft fractures among women taking bisphosphonates for greater than 5 years were attributable to extended bisphosphonate use; and that approximately 1 of every 10 subtrochanteric or femoral shaft fractures cases in the population might be prevented if no patient received more than 5 years of exposure. Among 52,595 women with at least 5
years of bisphosphonate therapy, a subtrochanteric or femoral shaft fracture occurred in 71 (0.13 percent) during the subsequent year and 117 (0.22 percent) within 2 years.
“In summary, our findings provide strong evidence that prolonged bisphosphonate therapy is associated with an increased risk of subtrochanteric or femoral shaft fracture, although the absolute risk of these fractures is low. These findings also highlight the need for a thoughtful assessment of individual risk of fracture when considering extended bisphosphonate therapy and that long-term use of these drugs may warrant reconsideration, especially in patients at relatively low risk of fracture. It may be appropriate to consider a drug holiday for selected patients, particularly as the cumulative duration of bisphosphonate therapy surpasses 5 years. Additional research is needed to better understand the prognosis of subtrochanteric or femoral shaft fractures among frail older adults, identify the specific subgroups of long- term users at the highest risk for these adverse effects, and explore whether interruptions in therapy reduce the risk of subtrochanteric or femoral shaft fractures over the long term,” the authors write.
They add that the results of their study should not deter clinicians and patients from using bisphosphonates in appropriate patients. “Our study confirms the known benefits of bisphosphonate treatment for typical osteoporotic fracture, and evidence suggests that bisphosphonate therapies are underused in individuals at high risk of fracture despite their established efficacy.”
Public release date: 22-Feb-2011
Old folk remedy revived: How tansy may be a treatment for herpes
For centuries tansy has been used as a folk remedy, but now scientists from Britain and Spain believe the plant may have medical benefits after all, as a treatment for herpes. The team’s findings, published in Phytotherapy Research, are the result of joint work between two teams to established scientific evidence for traditional medicines.
Tansy, Tanacetum vulgare, is a flowering plant found across mainland Europe and Asia. From the Middle Ages onwards the plant, whose folk names include Golden Buttons and Mugwort, has been used as a remedy for various conditions, from fevers to rheumatism. However, it’s supposed medical benefits have always been questioned.
“Our research focused on the anti-viral properties of tansy, especially the potential treatment it may represent for herpes,” said lead author Professor Francisco Parra from the Universidad de Oviedo. “We currently lack an effective vaccine for either HSV-1 or HSV-2 stands of the disease, which can cause long term infections.”
Professor Parra’s team which specialises in investigating new antiviral compounds, both through design or by screening natural plant extracts, began joint work on the properties of tansy with the research group led by Dr Solomon Habtemariam from the University of Greenwich, which studies European medicinal plants to establish the scientific evidence for traditional medicines.
Through a mechanistic-based antiherpetic activity study, the teams revealed which constituents of the plant are responsible for antiviral activity.
“Our study revealed that parthenolide is not one of the major anti HSV-1 principles of tansy, as has been suggested. However we found that tansy does contains known antiviral agents including 3,5- dicaffeoylquinic acid (3,5-DCQA) as well as axillarin, which contributes to its antiherpetic effect,” said Parra. “This shows that multiple properties of the plant are responsible for the supposed antiviral activity of tansy.”
The joint study used an established anti-HSV study model on both crude extracts of the aerial parts and roots of tansy, as well as some purified compounds to analyse the plants anti-viral activity.
“Although the precise molecular targets for tansy extract require further research this study reveals the clear potential of tansy to treat the dermatological lesions caused by HSV, concluded Parra. “This shows that systematic pharmacological and phytochemical studies such as this can play pivotal roles in the modernisation of European traditional herbal medicines.”
Public release date: 22-Feb-2011
Higher vitamin D intake needed to reduce cancer risk
Researchers at the University of California, San Diego School of Medicine and Creighton University School of Medicine in Omaha have reported that markedly higher intake of vitamin D is needed to reach blood levels that can prevent or markedly cut the incidence of breast cancer and several other major diseases than had been originally thought. The findings are published February 21 in the journal Anticancer Research
While these levels are higher than traditional intakes, they are largely in a range deemed safe for daily use in a December 2010 report from the National Academy of Sciences Institute of Medicine.
“We found that daily intakes of vitamin D by adults in the range of 4000-8000 IU are needed to maintain blood levels of vitamin D metabolites in the range needed to reduce by about half the risk of several diseases – breast cancer, colon cancer, multiple sclerosis, and type 1 diabetes,” said Cedric Garland, DrPH, professor of family and preventive medicine at UC San Diego Moores Cancer Center. “I was surprised to find that the intakes required to maintain vitamin D status for disease prevention were so high – much higher than the minimal intake of vitamin D of 400 IU/day that was needed to defeat rickets in the 20th century.”
“I was not surprised by this” said Robert P. Heaney, MD, of Creighton University, a distinguished biomedical scientist who has studied vitamin D need for several decades. “This result was what our dose- response studies predicted, but it took a study such as this, of people leading their everyday lives, to confirm it.”
The study reports on a survey of several thousand volunteers who were taking vitamin D supplements in the dosage range from 1000 to 10,000 IU/day. Blood studies were conducted to determine the level of 25- vitamin D – the form in which almost all vitamin D circulates in the blood.
“Most scientists who are actively working with vitamin D now believe that 40 to 60 ng/ml is the appropriate target concentration of 25-vitamin D in the blood for preventing the major vitamin D- deficiency related diseases, and have joined in a letter on this topic,” said Garland. “Unfortunately, according a recent National Health and Nutrition Examination Survey, only 10 percent of the US population has levels in this range, mainly people who work outdoors.”
Interest in larger doses was spurred in December of last year, when a National Academy of Sciences Institute of Medicine committee identified 4000 IU/day of vitamin D as safe for every day use by adults and children nine years and older, with intakes in the range of 1000-3000 IU/day for infants and children through age eight years old.
While the IOM committee states that 4000 IU/day is a safe dosage, the recommended minimum daily intake is only 600 IU/day.
“Now that the results of this study are in, it will become common for almost every adult to take 4000
IU/day,” Garland said. “This is comfortably under the 10,000 IU/day that the IOM Committee Report considers as the lower limit of risk, and the benefits are substantial.” He added that people who may have contraindications should discuss their vitamin D needs with their family doctor.
“Now is the time for virtually everyone to take more vitamin D to help prevent some major types of cancer, several other serious illnesses, and fractures,” said Heaney.
Public release date: 23-Feb-2011
Microbes help children to breathe easily
Bacteria and fungi offer protection against asthma
The incidence of asthma among children in Europe continues to rise. But not all children are equally at risk. Several studies published over the past few years have shown that children living on farms are significantly less likely to develop asthma than others. An international team of researchers including Dr. Markus Ege and Professor Erika von Mutius of Children’s Surgical Clinic in the Dr. von Hauner Children’s Hospital (Medical Center of the University of Munich) has just published an epidemiological study that confirms this finding. It shows that the lower susceptibility of farm children to asthma can largely be accounted for by the fact that they are exposed to a greater variety of microorganisms than other children living in the same regions. The physiological mechanisms underlying the effect remain to be elucidated, but the investigators have identified several species that might be responsible for the reduction in asthma risk. The results have broad implications for the prevention of asthma in other sectors of the population. “We have a long way to go before we can present new preventive measures, but at least we now have candidates for the development of a vaccine,” says Ege. (New England Journal of Medicine online, 24 February 2011)
Asthma is among the most prevalent chronic illnesses among children in Europe, and in many cases the condition will remain with them all their lives. This is why asthma presents such a challenge for health- care systems. The disease results from a combination of genetic and environmental factors, and various studies have shown that farm children have a significantly lower risk of developing the condition than other children. In order to identify the reasons for this difference, LMU researchers selected a group of Bavarian schoolchildren for detailed study. In the context of two large-scale, pan-European, epidemiological projects, named GABRIEL and PARSIFAL, Ege and his colleagues compared children living on farms with others from the same rural districts who had little direct contact with farms.
In the new work, the investigators focused on the microbes present in domestic interiors. They collected household dust from children’s bedrooms, and analyzed the bacterial and fungal DNAs in the samples. The results showed that farm children must cope with a much greater range of microorganisms than are children who live in other types of environment. The bacteria and fungi seem to act as guardians of health, for it turned out that the more diverse the microbial population, the lower the risk of asthma.
Exactly how the cells and spores perform this trick is still unclear, but the researchers suggest a couple of possible explanations. “One possibility is that a particular combination of microbial species stimulates the innate immune system and so prevents it from entering a state that promotes the development of asthma,” says Ege. Another model proposes that continuous exposure to many different microorganisms makes it more difficult for the species that potentially induce asthma to become the dominant forms in the lower respiratory tract – similarly to the gastrointestinal tract, where a balanced population of microbes is necessary for optimal organ function.
Microbial diversity alone, however, is not enough to prevent asthma. More probably, it takes a particular consortium of species to exert a protective effect. “Within the large spectrum of organisms that we examined, there are some that may be of special interest,” reports Ege. “Among these are certain species of bacilli and staphylococci – Staphylococcus sciuri, for instance – as well as fungi of the genus
Eurotium.” The next challenge facing the team is to elucidate, at the level of single species, the nature of the link between the microorganisms in household dust and the protective effect, with the long-term goal of identifying candidates that might serve as the basis of a live vaccine against asthma.
Public release date: 24-Feb-2011
Is dairy colostrum the key to Olympic success?
Scientistsinvestigatingnaturalwaysto enhance athletic performance have found that bovine colostrum can massively reduce gut permeability – otherwise known as ‘leaky gut syndrome.’ Their findings, published in the March issue of the American Journal of Physiology-Gastrointestinal and Liver Physiology, could have positive implications not just for athletes but also for sufferers of heatstroke.
A research group led by Ray Playford, Professor of Medicine at Barts and The London School of Medicine and Dentistry looked at athletes who were asked to run for 20 minutes at 80 per cent of their aerobic maximum. At the end of the exercise, changes in the subjects gut leakiness were measured using urine sample – also determined were changes in the athletes’ core temperature. Under standard conditions, gut leakiness had increased by 250 per cent and temperature had risen by 2 degrees. However, when the group were given a drink of dairy colostrum for two weeks before the trial, the rise in gut leakiness was reduced by about 80 per cent, despite the same effort and temperature rise.
Gut disorders induced by exercise are common in runners – the body’s response to increased permeability is to clear the gut contents, giving rise to symptoms such as diarrhoea to avoid toxins from gut organisms entering the bloodstream, as these lead to heatstroke which can result in damage to the internal organs.
Professor Playford’s research identified changes in gut barrier function in laboratory studies: gut cells were cultured at normal 37 degrees body heat and at 39 degrees to replicate the temperature after exercise. The death rate of gut cells was much increased at the higher temperature yet when colostrum was added to the culture medium the rise in cell death rate was reduced by two thirds.
Professor Ray Playford said: “Athletes’ performance can be seriously diminished due to gut symptoms during heavy exercise. We have been looking at natural approaches to reduce this problem as the range of products that athletes can legitimately take is very limited. Our findings suggest colostrum may have real value in helping our athletes perform. This is a research area we are especially interested in given our proximity to the 2012 Olympic site. In addition, extremes of temperature and exercise are often suffered by armed forces in desert war scenarios and can result in heat stroke which is life threatening. Based on our results to date, our research group is also exploring products that may be useful for protecting soldiers in life threatening situations such as these.”
Public release date: 24-Feb-2011
Low vitamin D levels linked to allergies in kids
February 24, 2011 ─ (BRONX, NY) ─ A study of more than 3,000 children shows that low vitamin D levels are associated with increased likelihood that children will develop allergies, according to a paper published in the February 17 online edition of the Journal of Allergy and Clinical Immunology.
Researchers from Albert Einstein College of Medicine of Yeshiva University headed the study. Researchers looked at the serum vitamin D levels in blood collected in 2005-2006 from a nationally
representative sample of more than 3,100 children and adolescents and 3,400 adults. The samples are derived from the National Health and Nutrition Examination Survey (NHANES), a program of studies designed to assess the health and nutritional status of adults and children in the United States. The survey is unique in that it combines interviews, physical examinations and laboratory studies. One of the blood tests assessed was sensitivity to 17 different allergens by measuring levels of Immunoglobulin E (IgE), a protein made when the immune system responds to allergens.
When the resulting data was analyzed by Einstein researchers, no association between vitamin D levels and allergies was observed in adults. But for children and adolescents, low vitamin D levels correlated with sensitivity to 11 of the 17 allergens tested, including both environmental allergens (e.g., ragweed, oak, dog, cockroach) and food allergens (e.g., peanuts). For example, children who had vitamin D deficiency (defined as less than 15 nanograms of vitamin D per milliliter of blood), were 2.4 times as likely to have a peanut allergy than were children with sufficient levels of vitamin D (more than 30 nanograms of vitamin D per milliliter of blood).
The research shows only an association and does not prove that vitamin D deficiency causes allergies in children, cautioned Michal Melamed, M.D., M.H.S., assistant professor of medicine and of epidemiology
& population health at Einstein and senior author of the study. Nevertheless, she said, children should certainly consume adequate amounts of the vitamin. “The latest dietary recommendations calling for children to take in 600 IU of vitamin D daily should keep them from becoming vitamin-D deficient,” she said.
Public release date: 24-Feb-2011
Probiotic identified to treat ulcers
Researchers from Spain have identified a strain of probiotic bacteria that may be useful in treating ulcers caused by Helicobacter pylori. They report their findings in the February 2011 issue of the journal Applied and Environmental Microbiology.
“H. pylori is considered one of the major risk factors underlying the development of gastritis and gastric and duodenal ulcers,” write the researchers. “Currently, antibiotic-based treatment for H. pylori infection is neither sufficient nor satisfactory, with the most successful treatments reaching 75 to 90% eradication rates. The use of probiotics is a potentially promising tool to prevent H. pylori.”
According to an expert consultation conducted by the Food and Agriculture Organization and the World Health Organization probiotics are “live microorganisms which when administered in adequate amounts confer a health benefit to the host.” The regular intake of probiotic microoganisms has been demonstrated to prevent several disorders including diarrhea and inflammatory bowel disease.
Among probiotics Bifidobacterium is one of the favorite genera in studies focused on the prevention of gastrointestinal infection and is often used in fermented dairy products or food supplements. Some studies have been done in vitro (in test tubes or petri dishes) showing bifidobacterial activity against H. pylori.
In this study, the researchers tested numerous strains of bifidobacteria isolated from the feces of breast-fed infants for activity against H. pylori. They identified one strain (Bifidobacterium bifidum CECT 7366) that under certain conditions had an inhibition level of nearly 95% in vitro and tested its activitity against infection in mice.
After 21 days, mice treated with the potentially probiotic strain developed significantly less ulcers than the control group. Additional tests suggest that treatment partially relieved damage to gastric tissue caused by
H. pylori infection. Ingestion of the bacteria did not induce any disease or mortality in both healthy and
“The results presented here confer to strain B. bifidum CECT 7366 the status of a probiotic bacterium with functional activity against H. pylori,” write the researchers. “Human clinical trials must be performed before commercialization of this strain can be approved.”
Public release date: 24-Feb-2011
AP IMPACT: Past medical testing on humans revealed
By MIKE STOBBE, AP Medical Writer Mike Stobbe, Ap Medical Writer 18 mins ago
ATLANTA – Shocking as it may seem, U.S. government doctors once thought it was fine to experiment on disabled people and prison inmates. Such experiments included giving hepatitis to mental patients in Connecticut, squirting a pandemic flu virus up the noses of prisoners in Maryland, and injecting cancer cells into chronically ill people at a New York hospital.
Much of this horrific history is 40 to 80 years old, but it is the backdrop for a meeting in Washington this week by a presidential bioethics commission. The meeting was triggered by the government’s apology last fall for federal doctors infecting prisoners and mental patients in Guatemala with syphilis 65 years ago.
U.S. officials also acknowledged there had been dozens of similar experiments in the United States — studies that often involved making healthy people sick.
An exhaustive review by The Associated Press of medical journal reports and decades-old press clippings found more than 40 such studies. At best, these were a search for lifesaving treatments; at worst, some amounted to curiosity-satisfying experiments that hurt people but provided no useful results.
Inevitably, they will be compared to the well-known Tuskegee syphilis study. In that episode, U.S. health officials
tracked 600 black men in Alabama who already had syphilis but didn’t give them adequate treatment even after penicillin became available.
These studies were worse in at least one respect — they violated the concept of “first do no harm,” a fundamental medical principle that stretches back centuries.
“When you give somebody a disease — even by the standards of their time — you really cross the key ethical norm of the profession,” said Arthur Caplan, director of the University of Pennsylvania’s Center for Bioethics.
Some of these studies, mostly from the 1940s to the ’60s, apparently were never covered by news media. Others were reported at the time, but the focus was on the promise of enduring new cures, while glossing over how test subjects were treated.
Attitudes about medical research were different then. Infectious diseases killed many more people years ago, and doctors worked urgently to invent and test cures. Many prominent researchers felt it was legitimate to experiment on people who did not have full rights in society — people like prisoners, mental patients, poor blacks. It was an attitude in some ways similar to that of Nazi doctors experimenting on Jews.
“There was definitely a sense — that we don’t have today — that sacrifice for the nation was important,” said Laura Stark, a Wesleyan University assistant professor of science in society, who is writing a book about past federal medical experiments.
The AP review of past research found:
_A federally funded study begun in 1942 injected experimental flu vaccine in male patients at a state insane asylum in Ypsilanti, Mich., then exposed them to flu several months later. It was co-authored by Dr. Jonas Salk, who a decade later would become famous as inventor of the polio vaccine.
Some of the men weren’t able to describe their symptoms, raising serious questions about how well they understood what was being done to them. One newspaper account mentioned the test subjects were “senile and debilitated.” Then it quickly moved on to the promising results.
_In federally funded studies in the 1940s, noted researcher Dr. W. Paul Havens Jr. exposed men to hepatitis in a series of experiments, including one using patients from mental institutions in Middletown and Norwich, Conn. Havens, a World Health Organization expert on viral diseases, was one of the first scientists to differentiate types of hepatitis and their causes.
A search of various news archives found no mention of the mental patients study, which made eight healthy men ill but broke no new ground in understanding the disease.
_Researchers in the mid-1940s studied the transmission of a deadly stomach bug by having young men swallow unfiltered stool suspension. The study was conducted at the New York State Vocational Institution, a reformatory prison in West Coxsackie. The point was to see how well the disease spread that way as compared to spraying the germs and having test subjects breathe it. Swallowing it was a more effective way to spread the disease, the researchers concluded. The study doesn’t explain if the men were rewarded for this awful task.
_A University of Minnesota study in the late 1940s injected 11 public service employee volunteers with malaria, then starved them for five days. Some were also subjected to hard labor, and those men lost an average of 14 pounds. They were treated for malarial fevers with quinine sulfate. One of the authors was Ancel Keys, a noted dietary scientist who developed K-rations for the military and the Mediterranean diet for the public. But a search of various news archives found no mention of the study.
_For a study in 1957, when the Asian flu pandemic was spreading, federal researchers sprayed the virus in the noses of 23 inmates at Patuxent prison in Jessup, Md., to compare their reactions to those of 32 virus- exposed inmates who had been given a new vaccine.
_Government researchers in the 1950s tried to infect about two dozen volunteering prison inmates with gonorrhea using two different methods in an experiment at a federal penitentiary in Atlanta. The bacteria was pumped directly into the urinary tract through the penis, according to their paper.
The men quickly developed the disease, but the researchers noted this method wasn’t comparable to how men normally got infected — by having sex with an infected partner. The men were later treated with antibiotics. The study was published in the Journal of the American Medical Association, but there was no mention of it in various news archives.
Though people in the studies were usually described as volunteers, historians and ethicists have questioned how well these people understood what was to be done to them and why, or whether they were coerced.
Prisoners have long been victimized for the sake of science. In 1915, the U.S. government’s Dr. Joseph Goldberger — today remembered as a public health hero — recruited Mississippi inmates to go on special rations to prove his theory that the painful illness pellagra was caused by a dietary deficiency. (The men were offered pardons for their participation.)
But studies using prisoners were uncommon in the first few decades of the 20th century, and usually performed by researchers considered eccentric even by the standards of the day. One was Dr. L.L. Stanley, resident physician at San Quentin prison in California, who around 1920 attempted to treat older, “devitalized men” by implanting in them testicles from livestock and from recently executed convicts.
Newspapers wrote about Stanley’s experiments, but the lack of outrage is striking.
“Enter San Quentin penitentiary in the role of the Fountain of Youth — an institution where the years are made to roll back for men of failing mentality and vitality and where the spring is restored to the step, wit to the brain, vigor to the muscles and ambition to the spirit. All this has been done, is being done … by a surgeon with a scalpel,” began one rosy report published in November 1919 in The Washington Post.
Around the time of World War II, prisoners were enlisted to help the war effort by taking part in studies that could help the troops. For example, a series of malaria studies at Stateville Penitentiary in Illinois and two other prisons was designed to test antimalarial drugs that could help soldiers fighting in the Pacific.
It was at about this time that prosecution of Nazi doctors in 1947 led to the “Nuremberg Code,” a set of international rules to protect human test subjects. Many U.S. doctors essentially ignored them, arguing that they applied to Nazi atrocities — not to American medicine.
The late 1940s and 1950s saw huge growth in the U.S. pharmaceutical and health care industries, accompanied by a boom in prisoner experiments funded by both the government and corporations. By the 1960s, at least half the states allowed prisoners to be used as medical guinea pigs.
But two studies in the 1960s proved to be turning points in the public’s attitude toward the way test subjects were treated.
The first came to light in 1963. Researchers injected cancer cells into 19 old and debilitated patients at a Jewish Chronic Disease Hospital in the New York borough of Brooklyn to see if their bodies would reject them.
The hospital director said the patients were not told they were being injected with cancer cells because there was no need — the cells were deemed harmless. But the experiment upset a lawyer named William Hyman who sat on the hospital’s board of directors. The state investigated, and the hospital ultimately said any such experiments would require the patient’s written consent.
At nearby Staten Island, from 1963 to 1966, a controversial medical study was conducted at the Willowbrook State School for children with mental retardation. The children were intentionally given hepatitis orally and by injection to see if they could then be cured with gamma globulin.
Those two studies — along with the Tuskegee experiment revealed in 1972 — proved to be a “holy trinity” that sparked extensive and critical media coverage and public disgust, said Susan Reverby, the Wellesley College historian who first discovered records of the syphilis study in Guatemala.
By the early 1970s, even experiments involving prisoners were considered scandalous. In widely covered congressional hearings in 1973, pharmaceutical industry officials acknowledged they were using prisoners for testing because they were cheaper than chimpanzees.
Holmesburg Prison in Philadelphia made extensive use of inmates for medical experiments. Some of the victims are still around to talk about it. Edward “Yusef” Anthony, featured in a book about the studies, says he agreed to have a layer of skin peeled off his back, which was coated with searing chemicals to test a drug. He did that for money to buy cigarettes in prison.
“I said ‘Oh my God, my back is on fire! Take this … off me!'” Anthony said in an interview with The
Associated Press, as he recalled the beginning of weeks of intense itching and agonizing pain.
The government responded with reforms. Among them: The U.S. Bureau of Prisons in the mid-1970s effectively excluded all research by drug companies and other outside agencies within federal prisons.
As the supply of prisoners and mental patients dried up, researchers looked to other countries.
It made sense. Clinical trials could be done more cheaply and with fewer rules. And it was easy to find patients who were taking no medication, a factor that can complicate tests of other drugs.
Additional sets of ethical guidelines have been enacted, and few believe that another Guatemala study could happen today. “It’s not that we’re out infecting anybody with things,” Caplan said.
Still, in the last 15 years, two international studies sparked outrage.
One was likened to Tuskegee. U.S.-funded doctors failed to give the AIDS drug AZT to all the HIV- infected pregnant women in a study in Uganda even though it would have protected their newborns. U.S. health officials argued the study would answer questions about AZT’s use in the developing world.
The other study, by Pfizer Inc., gave an antibiotic named Trovan to children with meningitis in Nigeria, although there were doubts about its effectiveness for that disease. Critics blamed the experiment for the deaths of 11 children and the disabling of scores of others. Pfizer settled a lawsuit with Nigerian officials for $75 million but admitted no wrongdoing.
Last year, the U.S. Department of Health and Human Services’ inspector general reported that between 40 and 65 percent of clinical studies of federally regulated medical products were done in other countries in 2008, and that proportion probably has grown. The report also noted that U.S. regulators inspected fewer than 1 percent of foreign clinical trial sites.
Monitoring research is complicated, and rules that are too rigid could slow new drug development. But it’s often hard to get information on international trials, sometimes because of missing records and a paucity of audits, said Dr. Kevin Schulman, a Duke University professor of medicine who has written on the ethics of international studies.
These issues were still being debated when, last October, the Guatemala study came to light.
In the 1946-48 study, American scientists infected prisoners and patients in a mental hospital in Guatemala with syphilis, apparently to test whether penicillin could prevent some sexually transmitted disease. The study came up with no useful information and was hidden for decades.
The Guatemala study nauseated ethicists on multiple levels. Beyond infecting patients with a terrible illness, it was clear that people in the study did not understand what was being done to them or were not able to give their consent. Indeed, though it happened at a time when scientists were quick to publish research that showed frank disinterest in the rights of study participants, this study was buried in file drawers.
“It was unusually unethical, even at the time,” said Stark, the Wesleyan researcher.
“When the president was briefed on the details of the Guatemalan episode, one of his first questions was whether this sort of thing could still happen today,” said Rick Weiss, a spokesman for the White House Office of Science and Technology Policy.
That it occurred overseas was an opening for the Obama administration to have the bioethics panel seek a new evaluation of international medical studies. The president also asked the Institute of Medicine to
further probe the Guatemala study, but the IOM relinquished the assignment in November, after reporting its own conflict of interest: In the 1940s, five members of one of the IOM’s sister organizations played prominent roles in federal syphilis research and had links to the Guatemala study.
So the bioethics commission gets both tasks. To focus on federally funded international studies, the commission has formed an international panel of about a dozen experts in ethics, science and clinical research. Regarding the look at the Guatemala study, the commission has hired 15 staff investigators and is working with additional historians and other consulting experts.
The panel is to send a report to Obama by September. Any further steps would be up to the administration.
Some experts say that given such a tight deadline, it would be a surprise if the commission produced substantive new information about past studies. “They face a really tough challenge,” Caplan said.
Public release date: 26-Feb-2011
Experts propose global guidelines for safe use and production of Kava
The South-Pacific plant has been traditionally used to reduce stress and anxiety but is restricted in some countries.
Leading world Kava experts Dr Jerome Sarris from the University of Melbourne, Australia; Professor Rolf Teschke from Wolfgang Goethe-University, Frankfurt, Germany; and Dr Vincent Lebot from CIRAD, Port-Vila, Vanuatu, have proposed a six-point plan that is intended to become the framework to assist in the re-introduction of Kava to restricted countries. The framework will ensure only high quality Kava to be consumed throughout the Pacific and the rest of the world.
The framework was recently published in the international journals Phytomedicine and The British Journal of Clinical Pharmacology.
“Kava can potentially be used safely if this framework for production and use is adopted,” Dr Jerome Sarris said.
Kava was restricted for use in 2002 in Europe, United Kingdom and Canada over concerns it may cause liver problems (on average one case per every 50 million doses). This was considered to be potentially due, in part, to companies using chemical extracts from poor quality material using an incorrect type of Kava.
Dr Sarris said the future regulatory and commercial strategies should focus not only on the standardisation of medicinal Kava products and traditional Kava extracts, but also on thorough surveillance during the manufacturing process to improve Kava quality for safe human use.
“It is intended now that these recommendations be taken up by Kava producing Pacific Island countries in order to reinvigorate the Kava industry and provide a pathway back to safe global use of the plant,” Dr Sarris said.
The use of the plant as a treatment for generalised anxiety is part of two human trials currently being conducted by Dr Sarris in Melbourne Australia, where it is available over the counter.
In Australia in 2005, the Australian Therapeutics Goods Administration allowed for water soluble extracts of Kava to be used for medicinal purposes.
He said preliminary results with the Mediherb extract showed the kava extract used was safe and effective
in reducing anxiety.
“We do however, need a larger study to validate this result,” Dr Sarris said. The six-point framework for the safe production of Kava is as follows:
1) Use of Kava plants at least five years old (“noble” type of Kava cultivar is preferred, as it is traditionally considered safe)
2) Use of the peeled rhizome (root) of Kava plant (not leaves or aerial parts)
3) Water-soluble extract for Kava (not alcohol or chemical solution to extract constituents)
4) Dosage recommendations of less than 250 mg of kavalactones (the active chemicals) per day for medicinal use
5) Systematic rigorous future research investigating safety issues (potentially from poorly stored and manufactured Kava material, and/or incorrect cultivar and plant material), and human clinical trials using noble cultivars prepared via good pharmaceutical manufacturing practice
6) A Pan-Pacific quality control system enforced by strict policing.
Public release date: 28-Feb-2011
Fish oil fights weight loss due to chemotherapy
A new analysis has found that supplementing the diet with fish oil may prevent muscle and weight loss that commonly occurs in cancer patients who undergo chemotherapy. Published early online in Cancer, a peer-reviewed journal of the American Cancer Society, the study indicates that fish oil may help combat cancer-related malnutrition.
Chemotherapy can cause cancer patients to lose muscle mass and become malnourished, leading to fatigue, a decreased quality of life, an inability to receive necessary treatments, and shorter survival.
Researchers suspect that supplementing the diet with fish oil—which contains omega-3 fatty acids such as eicosapentaenoic acid—may help patients maintain or gain muscle. To test the hypothesis, Vera Mazurak, PhD, of the University of Alberta in Edmonton, Canada, led a team that compared the effects of fish oil with that of standard care (no intervention) on weight, muscle, and fat tissue in newly referred non-small cell lung cancer patients.
The trial involved 16 patients who took fish oil (2.2 grams of eicosapentaenoic acid/day) and 24 patients who did not. The study ran until patients completed their first-line (initial) chemotherapy treatments, which lasted about 10 weeks. Muscle and fat were periodically measured using computed tomography images. Blood was collected and weight was recorded at the start of the study and throughout chemotherapy.
Patients who did not take fish oil lost an average of 2.3 kilograms whereas patients receiving fish oil maintained their weight. Patients with the greatest increase in eicosapentaenoic acid concentration in the blood following fish oil supplementation had the greatest gains in muscle. Sixty-nine percent of patients in the fish oil group gained or maintained muscle mass. Comparatively, only 29 percent of patients in the standard care group maintained muscle mass, and overall, patients in this group lost 1 kilogram of muscle. No difference in total fat tissue was observed between the two groups.
The authors concluded that nutritional intervention with two grams of fish oil per day provides a benefit over standard care, allowing patients to maintain their weight and muscle mass during chemotherapy. “Fish oil may prevent loss of weight and muscle by interfering with some of the pathways that are altered in advanced cancer,” said Dr. Mazurak. “This holds great promise because currently there is no effective treatment for cancer-related malnutrition,” she added. Dr. Mazurak noted that fish oil is safe and non-
toxic with virtually no side effects. It may be beneficial to patients with other forms of cancer and other chronic diseases that are associated with malnutrition, as well as to elderly individuals who are at risk for muscle loss.
Public release date: 1-Mar-2011
Study links vitamin D to lung cancer survival
U-M researchers find high levels of enzyme that blocks vitamin D can predict lung cancer survival
ANN ARBOR, Mich. — Recent research suggests vitamin D may be able to stop or prevent cancer. Now, a new study finds an enzyme that plays a role in metabolizing vitamin D can predict lung cancer survival.
The study, from researchers at the University of Michigan Comprehensive Cancer Center, suggests that this enzyme stops the anti-cancer effects of vitamin D.
Levels of the enzyme, called CYP24A1, were elevated as much as 50 times in lung adenocarcinoma compared with normal lung tissue. The higher the level of CYP24A1, the more likely tumors were to be aggressive. About a third of lung cancer patients had high levels of the enzyme. After five years, those patients had nearly half the survival rate as patients with low levels of the enzyme.
Researchers then linked this to how CYP24A1 interacts with calcitriol, the active form of vitamin D. CYP24A1 breaks down calcitriol, which has a normal and crucial role when kept in check. But when levels of CYP24A1 climb, the enzyme begins to hinder the positive anti-cancer effects of vitamin D.
Results of the study appear in Clinical Cancer Research.
Previous studies have linked low levels of vitamin D to a higher incidence of cancer and worse survival. Researchers are looking at using vitamin D to help prevent lung cancer from returning and spreading after surgery. This new study suggests the possibility of using CYP24A1 levels to personalize this approach to those likely to benefit most.
“Half of lung cancers will recur after surgery, so it’s important to find a way to prevent or delay this recurrence. A natural compound like vitamin D is attractive because it has few side effects, but it’s even better if we can determine exactly who would benefit from receiving vitamin D,” says study author Nithya Ramnath, M.D., associate professor of internal medicine at the U-M Medical School.
Researchers also are working to identify drugs that block CYP24A1. Blocking the enzyme would reinstate the positive anti-cancer effects of vitamin D, suggesting that this inhibitor could potentially be combined with vitamin D treatments.
Public release date: 2-Mar-2011
Study shows pine bark naturally improves kidney function in patients with metabolic syndrome
Research reveals Pycnogenol demonstrates kidney protective benefits and lowers elevated blood pressure and blood sugar
(Mar. 2, 2011) – HOBOKEN, NJ – The American Heart Association estimates 35 percent of adults in the
U.S. suffer from metabolic syndrome, a group of risk factors characterized by obesity and the simultaneous presence of heart disease risk factors with high blood pressure, blood sugar and lipids. In patients with
metabolic syndrome, high blood pressure and blood glucose gradually impair kidney function, which in turn affects the organ’s ability to filter waste from the body. A study published in the June 2010 issue of Panminerva Medica reveals Pycnogenol® (pic-noj-en-all), an antioxidant plant extract from the bark of the French maritime pine tree, demonstrates kidney health benefits in metabolic syndrome patients, with effective blood pressure control, reduced blood sugar, and further noticed lowered Body Mass Index (BMI) due to weight loss.
“Kidney damage is a common problem for people with metabolic syndrome due to the large number of cardiovascular rick factors involved. Similar to hypertension, there are no warning signs for suffering kidneys. Poor kidney function may further increase blood pressure, which in turn deteriorates the situation of the kidneys in a vicious circle” said Dr. Peter Rohdewald, a lead researcher of the study. “The results of this study demonstrate Pycnogenol®’s ability not only to control hypertension, but also to restore kidney function in those impacted by metabolic syndrome. Surprisingly, people taking Pycnogenol® not only demonstrated lower blood glucose levels, but also significant weight loss during the six months, yielding optimistic results for managing this condition.”
The controlled study carried out at the Nephrology Unit at the L’Aquila Hospital in Italy investigated 58 hypertensive patients who presented all of the criteria for diagnosis of metabolic syndrome, as defined by the World Health Organization: hypertension, high blood lipids, high fasting blood glucose and obesity. Furthermore, all patients showed early signs of kidney problems as judged by elevated amounts of proteins (albumin) present in their urine.
Patients were divided into two groups and instructed to follow a healthier lifestyle with dietary improvements, moderate exercise and effective management of health risk factors. Both groups were treated with anti-hypertensive medication Ramipril, taking a standard dosage of 5 mg twice a day, with one group of 31 patients taking Pycnogenol® in addition to the medication.
In the group taking Pycnogenol®, 50 mg Pycnogenol® tablets were taken three times a day at approximately 8 a.m., 4 p.m. and 10 p.m., a total dosage of 150 mg of Pycnogenol® per day. Urine was collected during a 24 hour period for quantification of the protein albumin in the urine at baseline and again after six months of treatment. Fasting blood was drawn for standard blood analysis. Systolic and diastolic blood pressure and heart rate were monitored in the morning.
The study also shows Pycnogenol® is effective for improving blood pressure in patients with metabolic syndrome. The study found that taking Pycnogenol® as an adjunct to Ramipril significantly further lowered systolic and diastolic blood pressure as compared to the group taking Ramipril alone. While average blood pressure in the Ramipril group was lowered to borderline-high 128.2/90.2 mmHg, the values in the group taking Pycnogenol® with Ramipril reached essentially normal values (122.2/85.3 mmHg) after six months of treatment.
Kidney function improved in both groups as judged by a significant reduction of protein detected in collected urine. With Ramipril alone, urinary protein decreased by 22 percent and with the addition of Pycnogenol® it decreased by 52.7 percent. Further, the group taking Pycnogenol® had a lowered fasting blood glucose level, which was reduced from high average value 135.6 mg/dL at baseline to reach essentially healthy reference value 102.3 mg/dL after six months of treatment. Pycnogenol® also led to a remarkable improvement of blood flow velocity of the kidney arteries. Blood flow velocity in the kidneys significantly increased with Ramipril from systolic 17.2 to 23.8 cm/sec and diastolic 4.2 to 2.0 cm/sec. The addition of Pycnogenol® was more effective, improving blood flow from systolic 18.2 to 27.2 and diastolic 4.1 to 9.8 cm/sec.
Only the group taking Pycnogenol® was found to have significantly lost weight after six months as compared to baseline, from average BMI 26.5 to 25.0.
“The number of people affected by metabolic syndrome is ever increasing and kidney disease is a growing
concern. Pycnogenol® cannot compensate for an unhealthy lifestyle, but certainly offers some urgently needed help. Our study suggests that essentially all major characteristics of metabolic syndrome are improved with Pycnogenol as part of a healthier lifestyle.” said Dr. Rohdewald.
This preliminary evaluation shows Pycnogenol® to offer a natural solution for individuals with metabolic syndrome, particularly for kidney protection. Previous studies have shown Pycnogenol® as a supplement to anti-hypertensive medication further improves kidney flow and kidney function. Pycnogenol® has also been shown in several studies to lower blood glucose in diabetic patients.
Public release date: 2-Mar-2011
Potassium levels possible key to racial disparity in Type 2 diabetes
Johns Hopkins researchers find mineral deficiency increases disease risk
Lower potassium levels in the blood may help explain why African-Americans are twice as likely to be diagnosed with type 2 diabetes as whites, according to a new study by Johns Hopkins researchers.
The findings, if confirmed, suggest that part of diabetes prevention may someday prove as easy as taking a cheap potassium supplement.
“This research doesn’t mean people should run out and start taking potassium supplements,” says Hsin- Chieh “Jessica” Yeh, Ph.D., an assistant professor of medicine at the Johns Hopkins University School of Medicine and an author of the study, which appears in the American Journal of Clinical Nutrition. “But we now know lower serum potassium is an independent risk factor for diabetes and that African- Americans have, on average, lower potassium levels than whites. What remains to be seen is if increasing potassium levels through diet or supplementation can prevent the most common form of diabetes.”
Yeh and her colleagues analyzed data from more than 12,000 participants in the Atherosclerosis Risk in Communities Study (ARIC), information collected from 1987 and 1996. The more than 2,000 African- Americans in the study had lower average serum potassium levels than the more than 9,000 whites in the study, and they were twice as likely to develop type 2 diabetes. The incidence of diabetes among study participants went up as potassium levels went down.
Type 2 diabetes affects more than 8 percent of Americans, or 23.6 million people, and the burden of the disease falls disproportionately on African-Americans. Many factors are thought to contribute to the greater prevalence of diabetes in African-Americans, including differences in socioeconomic status, diet, obesity and genetics. But researchers say these do not account for the entire disparity.
Serum potassium, Yeh and her colleagues found, appears to be a novel risk factor for the disorder that may explain some of the racial disparity in diabetes risk, and one that may be as important as obesity. A recent study found that the racial disparity in diabetes prevalence has widened the most in normal-weight and overweight people rather than the obese, suggesting that additional factors other than weight contribute to the risk.
Yeh notes that low potassium levels have been linked in healthy people to higher insulin and higher glucose levels — two hallmarks of diabetes.
Previous studies have shown that African-Americans get less potassium in their diets than whites in the United States, on average just half of the government recommended 4,700 milligrams per day. Potassium comes from many sources such as bananas, melons, lentils and yogurt.
Determining whether a patient is potassium deficient would be simple to do, Yeh says, as part of a basic
set of metabolic tests routinely ordered by primary care doctors.
Yeh says she would like to see clinical trials developed to examine whether manipulating potassium levels
— either through diet changes or the addition of supplements — would reduce diabetes risk for some groups.
“That is to be determined,” Yeh says. But “if this works,” she adds, “this would be a very low-cost, practical way to prevent diabetes.”
Public release date: 2-Mar-2011
Polishing the apple’s popular image as a healthy food
Scientists are reporting the first evidence that consumption of a healthful antioxidant substance in apples extends the average lifespan of test animals, and does so by 10 percent. The new results, obtained with fruit flies — stand-ins for humans in hundreds of research projects each year — bolster similar findings on apple antioxidants in other animal tests. The study appears in ACS’s Journal of Agricultural and Food Chemistry.
Zhen-Yu Chen and colleagues note that damaging substances generated in the body, termed free radicals, cause undesirable changes believed to be involved in the aging process and some diseases. Substances known as antioxidants can combat this damage. Fruits and vegetables in the diet, especially brightly colored foods like tomatoes, broccoli, blueberries, and apples are excellent sources of antioxidants. A previous study with other test animals hinted that an apple antioxidant could extend average lifespan. In the current report, the researchers studied whether different apple antioxidants, known as polyphenols, could do the same thing in fruit flies.
The researchers found that apple polyphenols not only prolonged the average lifespan of fruit flies but helped preserve their ability to walk, climb and move about. In addition, apple polyphenols reversed the levels of various biochemical substances found in older fruit flies and used as markers for age-related deterioration and approaching death. Chen and colleagues note that the results support those from other studies, including one in which women who often ate apples had a 13-22 percent decrease in the risk of heart disease, and polish the apple’s popular culture image as a healthy food.
Public release date: 2-Mar-2011
Non-steroidal anti-inflammatory drugs linked to increased risk of erectile dysfunction
Men who take non-steroidal anti-inflammatory drugs three times a day for more than three months are 2.4 times more likely to have erectile dysfunction compared to men who do not take those drugs regularly, according to a Kaiser Permanente study published online in The Journal of Urology.
While previous research showed a trend toward this same finding, this observational study used electronic health records, an automated pharmacy database and self-reported questionnaire data to examine NSAID use and ED in an ethnically diverse population of 80,966 men aged 45 to 69 years throughout California.
After controlling for age, race, ethnicity, smoking status, diabetes, hypertension, heart disease, high cholesterol and body mass index, the researchers found that ED was 1.4 times more likely — a modest risk
— among regular NSAID users compared to men who did not take the drugs regularly. This association was consistent across all age groups.
“This study is a great example of how we work to understand the safety and effectiveness of what we recommend for our patients. We went into this study thinking we would find the opposite effect: that NSAIDs would have a protective effect because they protect against heart disease, which is also linked to ED,” said study senior author Steven J. Jacobsen, MD, PhD, an epidemiologist and director of research for Kaiser Permanente Southern California. “The next step is to dive a bit deeper to understand the underlying physiology of what might be happening with these drugs.”
Erectile dysfunction is a common problem in many middle-aged and elderly men. According to the National Institutes of Health, approximately 5 percent of 40-year-old men and between 15 and 25 percent of 65-year-old men experience ED on a long-term basis.
However, the researchers caution that men should not stop taking NSAIDs based on this study.
“There are many proven benefits of non steroidals in preventing heart disease and for other conditions. People shouldn’t stop taking them based on this observational study. However, if a man is taking this class of drugs and has ED, it’s worth a discussion with his doctor,” Jacobsen said.
Public release date: 3-Mar-2011
Scientists call for ‘swifter and sounder’ testing of chemicals
Looking at toxicology alone is not enough
PULLMAN, Wash.—Scientific societies representing 40,000 researchers and clinicians are asking that federal regulators tap a broader range of expertise when evaluating the risks of chemicals to which Americans are being increasingly exposed.
Writing in a letter in the journal Science, eight societies from the fields of genetics, reproductive medicine, endocrinology, developmental biology and others note that some 12,000 new substances are being registered with the American Chemical Society daily. Few make it into the environment, but the top federal regulators, the U.S. Food and Drug Administration and the Environmental Protection Agency, often lack information about the hazards of chemicals produced in high volumes.
“The need for swifter and sounder testing and review procedures cannot be overstated,” the letter states.
Patricia Hunt, a professor in the Washington State University School of Molecular Biosciences and corresponding author of the letter, said the FDA and EPA need to look beyond the toxicology of substances to the other ways chemicals can affect us.
“One of the problems they have is they look at some of the science and don’t know how to interpret it because it’s not done using the traditional toxicology testing paradigm,” she said. “We need geneticists, we need developmental and reproductive biologists and we need the clinical people on board to actually help interpret and evaluate some of the science.”
“As things stand now,” she added, “things get rapidly into the marketplace and the testing of them is tending to lag behind.”
Hunt said the letter was driven in particular by growing concerns about chemicals like the plasticizer bisphenol A, or BPA, subject of more than 300 studies finding adverse health effects in animals. Because such chemicals look like hormones to our body, they’re like strangers getting behind the wheels of our cars, Hunt said.
“Hormones control everything—our basic metabolism, our reproduction,” she said. “We call them
endocrine disruptors. They’re like endocrine bombs to a certain extent because they can disrupt all these normal functions.”
Hunt’s testimony last year helped make Washington the fifth state to outlaw BPA in children’s food containers and drinking cups.
Public release date: 3-Mar-2011
Sperm quality and counts worsening in Finland
A new study published in the International Journal of Andrology reveals that semen quality has significantly deteriorated during the last ten years in Finland, a country that previously was a region with high sperm counts. At the same time, the incidence of testis cancer in the Finnish population showed a remarkable increase, following the worrying trends observed in several countries in Europe and the Americas.
Led by Jorma Toppari, MD, PhD, of the University of Turku, researchers examined three cohorts of 19 year old men between the years of 1998 and 2006. The men that were born in the late 1980s had lower sperm counts than those who were born in the beginning of the 1980s. The total sperm counts were 227 million, 202 and 165 for men born in 1979-81, 1982-83 and 1987, respectively. Less than 10 % of sperm are structurally normal, and the number of morphologically normal sperm declined from 18 million to 11.
At the same time, the younger and more recently born men also had higher incidences of testis cancer than the older generations. The incidence rate is many fold higher for Finns born around 1980 compared with men born around 1950.
The underlying cause for these simultaneously occurring adverse trends remains unknown. However, the rapid change strongly points to environmental reasons. Endocrine disrupting compounds acting during development have been hypothesized to be a cause.
“Our findings further necessitate the efforts to identify reasons for the adverse trends in reproductive health to make preventive measures possible,” Toppari notes.
Public release date: 3-Mar-2011
Study finds MRSA danger in gyms may be exaggerated
Washington, DC, March 3, 2011 – Community gym surfaces do not appear to be reservoirs for MRSA transmission, according to a study published in the March issue of the American Journal of Infection Control, the official publication of APIC – the Association for Professionals in Infection Control and Epidemiology.
The purpose of the study, conducted by researchers from the University of Florida College of Medicine, was to determine whether community gymnasium equipment surfaces could harbor staphylococcal colonies and to assess whether disinfection lowers the rate of bacterial transmission. A total of 240 samples were collected from three local gyms, before and after cleaning, at three different times. Each sample was analyzed for methicillin-resistant Staphylococcus aureus (MRSA) and methicillin- sensitive Staphylococcus aureus (MSSA). In all 240 samples, none were positive for MRSA or MSSA.
“Despite the increasing incidence of community-acquired MRSA/MSSA infections, the gyms that we studied do not appear to be significant sources of staphylococcal infection,” commented lead investigator
Kathleen Ryan, MD, Department of Pediatrics, College of Medicine, University of Florida. “Aggressive and expensive surface disinfection programs may not be warranted in certain gymnasium settings.”
MRSA is known to remain viable on dry surfaces for extended periods. With rising concerns about spread of infection, gyms have begun extensive cleaning programs, and some offer complimentary wipes for use by the patrons.
Equipment tested in each gym included two separate gym mats, benches, dumbbells, cardio machines, and weight machines. The first swabbing was completed at midday to serve as a baseline. A second sample was obtained in the two gyms that offered wipes shortly after equipment was cleaned with the wipes provided for discretionary use. A third sample was obtained shortly after equipment was cleaned according to the gym’s standard cleaning practices.
“This study supports the evidence that transmission [of MRSA] is more likely to originate from skin- to-skin contact than skin-to-surface contact in the community,” say the authors.
The authors recognize that broad conclusions should not be drawn from a study of this size and they suggest that future studies could swab recently used clothing of gym patrons, doorknobs, water fountains, or other areas within the locker room that might be more susceptible to colonization by MRSA and MSSA.
MRSA is an antibiotic-resistant bacteria that can lead to severe infections and is associated with approximately 19,000 deaths annually, according to the Centers for Disease Control and Prevention (CDC). The annual cost to treat MRSA in hospitalized patients is estimated at $3.2 to 4.2 billion.
Public release date: 3-Mar-2011
Solving a traditional Chinese medicine mystery
Discovery of molecular mechanism reveals antitumor possibilities
Researchers at the Johns Hopkins School of Medicine have discovered that a natural product isolated from a traditional Chinese medicinal plant commonly known as thunder god vine, or lei gong teng, and used for hundreds of years to treat many conditions including rheumatoid arthritis works by blocking gene control machinery in the cell. The report, published as a cover story of the March issue of Nature Chemical Biology, suggests that the natural product could be a starting point for developing new anticancer drugs.
“Extracts of this medicinal plant have been used to treat a whole host of conditions and have been highly lauded for anti-inflammatory, immunosuppressive, contraceptive and antitumor activities,” says Jun O. Liu, Ph.D., a professor of pharmacology and molecular sciences at Johns Hopkins. “We’ve known about the active compound, triptolide, and that it stops cell growth, since 1972, but only now have we figured out what it does.”
Triptolide, the active ingredient purified from the plant Tripterygium wilfordii Hook F, has been shown in animal models to be effective against cancer, arthritis and skin graft rejection. In fact, says Liu, triptolide has been shown to block the growth of all 60 U.S. National Cancer Institute cell lines at very low doses, and even causes some of those cell lines to die. Other experiments have suggested that triptolide interferes with proteins known to activate genes, which gives Liu and colleagues an entry point into their research.
The team systematically tested triptolide’s effect on different proteins involved with gene control by looking at how much new DNA, RNA and protein is made in cells. They treated HeLa cells with triptolide
for one hour, compared treated to untreated cells and found that triptolide took much longer to have an effect on the levels of newly made proteins and DNA, yet almost immediately blocked manufacture of new RNA. The researchers then looked more closely at the three groups of enzymes that make RNA and found that low doses of triptolide blocked only one, RNAPII.
But the RNAPII enzyme complex actually requires the assistance of several smaller clusters of proteins, according to Liu, which required more investigative narrowing down. Using a small gene fragment in a test tube, the researchers mixed in RNAPII components and in some tubes included triptolide and some not to see which combinations resulted in manufacture of new RNA. Every combination of proteins that included a cluster called TFIIH stopped working in the presence of triptolide.
But again, TFIIH is made of 10 individual proteins, many of which, according to Liu, have distinct and testable activities. Using information already known about these proteins and testing the rest to see if triptolide would alter their behaviors, the research team finally found that triptolide directly binds to and blocks the enzymatic activity of one of the 10, the XPB protein.
“We were fairly certain it was XPB because other researchers had found triptolide to bind to an unknown protein of the same size, but they weren’t able to identify it,” says Liu. ”
To convince themselves that the interaction between triplotide and XPB is what stops cells from growing, the researchers made 12 chemicals related to triplotide with a wide range of activity and treated HeLa cells with each of the 12 chemicals at several different doses. By both counting cells and testing XPB activity levels, the team found that the two correlate; chemicals that were better at decreasing XPB activity were also better at stopping cell growth and vice versa.
“Triptolide’s general ability to stop RNAPII activity explains its anti-inflammatory and anticancer effects,” says Liu. “And its behavior has important additional implications for circumventing the resistance that some cancer cells develop to certain anticancer drugs. We’re eager to study it further to see what it can do for future cancer therapy.”
Public release date: 4-Mar-2011
Can you predict your mate will cheat by their voice?
When choosing a partner, women believe the lower the man’s voice, the more likely he’s going to cheat. Conversely, men think a woman with a higher voice is more likely to be unfaithful, researchers have found.
The study, published in the latest edition of the online journal Evolutionary Psychology is the first to examine the link between voice pitch and perceived infidelity and offers insight into the evolution of the human voice and how we choose our mates.
“In terms of sexual strategy, we found that men and women will use voice pitch as a warning sign of future betrayal. So the more attractive the voice—a higher pitch for women and lower pitch for men—the more likely the chances he or she will cheat,” says Jillian O’Connor, a graduate student in the Department of Psychology, Neuroscience & Behaviour at McMaster University and lead author of the study.
“Infidelity is costly with the emotional impact, financial costs and potential loss of the family unit. But this suggests that through the evolutionary process, we have learned ways to avoid partners who may be unfaithful as a protection mechanism,” she says.
Participants in the study were asked to listen to two versions of recorded clips from a male voice and a female voice, which were electronically manipulated to be both higher and lower in pitch. They were then
asked which one, from each pair, was more likely to cheat sexually on their romantic partner.
“The reason voice pitch influences perceptions of cheating is likely due to the relationship between pitch, hormones and infidelity,” explains David Feinberg, an assistant professor in the Department of Psychology, Neuroscience & Behaviour and advisor on the study. “Men with higher testosterone levels have lower pitched voices, and women with higher estrogen levels have higher pitched voices. High levels of these hormones are associated with adulterous behaviour and our findings indicate individuals are somewhat aware of the link and may use this in their search for a romantic partner.”