Health Technology Research Synopsis
25th Issue Date 20 FEB 2008
Compiled By Ralph Turchiano
Editors Top Five:
1. Purple pigments and obesity 2. Fake malaria drugs made in China; how the winter vomiting virus evolves 3. Study finds patients with complex fibroadenomas can avoid surgery 4. A compound extracted from olives inhibits cancer cells growth and prevents their appearance 5. Flu Vaccine doesn’t match most circulating viruses, health officials say
In this Issue:
- New study suggests link between environmental toxins and early onset puberty in girls
- Europe’s most common genetic disease is a liver disorder ( hemochromatosis )
- Sleep Duration May Play Important Role in Childhood Obesity
- Study suggests new therapy for lung disease patients (Current Therapy Wrong)
- Anti-cancer drug damages brain vessels
- Fatty acids beneficial in treatment for dry eye syndrome
- Purple pigments and obesity
- Fake malaria drugs made in China; how the winter vomiting virus evolves
- Autopsy findings suggest end of decline in coronary disease rates
- Study finds patients with complex fibroadenomas can avoid surgery
- Some cases of autism may be traced to the immune system of mothers during pregnancy
- A compound extracted from olives inhibits cancer cells growth and prevents their appearance
- U of I study: exercise to avoid gallstones!
- Metabolic syndrome linked to cold tolerance
- Cell phone-cancer link found by Tel Aviv University scientist
- Health effects of pesticide mixtures: Unexpected insights from the salmon brain
- As depression symptoms improve with antidepressants, hopelessness can linger
- Vaccine doesn’t match most circulating viruses, health officials say
- FDA ties pneumonia deaths to infant vaccine
Public release date: 6-Feb-2008
New study suggests link between environmental toxins and early onset puberty in girls
Cincinnati, February 6, 2008 – Although scientists have speculated over the negative effects of environmental toxins for years, new data suggest that certain environmental toxins may disrupt the normal growth and hormonal development of girls. Some of these toxins, such as the mycoestrogen zearalenone (ZEA) produced by the Fusarium fungus species, can be found naturally in the environment, have properties similar to the female reproductive hormone estrogen, and are also structurally similar to anabolic growth agents used in animal breeding. A new study scheduled for publication in The Journal of Pediatrics suggests that certain mycoestrogens may be directly linked to the early onset of sexual development in young girls.
Dr. Francesco Massart and colleagues from the University of Pisa in Italy studied a group of girls affected by the early onset of puberty, or central precocious puberty (CPP), from the North-West region of Tuscany. They undertook the study to explain why this area has a much higher than average incidence of CPP. The authors tested the girls for mycoestrogens to see if environmental toxins were a factor in the girls’ premature sexual development.
Six of the 17 girls with CPP were found to have elevated levels of ZEA. According to Dr. Massart, “Although this finding might be incidental, ZEA may be related to CPP occurrence in girls exposed to mycoestrogens. However, the presence of ZEA pollution could not explain the epidemic of CPP in the region, suggesting that other environmental factors such as herbicides and pesticides may be involved.”
The authors also noted that because of its chemical resemblance to some anabolic growth agents used in animal breeding, ZEA may promote accelerated growth in exposed children. Though the researchers were unable to identify a definitive cause of the high rates of CPP in this region of Tuscany, the study identifies the need for more research into the possible negative effects of environmental pollutants on children.
Public release date: 6-Feb-2008
Europe’s most common genetic disease is a liver disorder ( hemochromatosis )
Researchers discover the origin of hereditary hemochromatosis, a common iron overload disorder, is a genetic defect in the liver
Much less widely known than the dangerous consequences of iron deficiencies is the fact that too much iron can also cause problems. The exact origin of the genetic iron overload disorder hereditary hemochromatosis [HH] has remained elusive. In a joint effort, researchers from the European Molecular Biology Laboratory [EMBL] and the University of Heidelberg, Germany, have now discovered that HH is a liver disease. They report in the current issue of Cell Metabolism that the disorder develops when a crucial gene is lacking in liver cells.
“For a long time scientists thought of HH as a disease of the intestine, because this is where iron uptake actually takes place,” says Matthias Hentze, Associate Director of EMBL. “Our research now reveals that the crucial point is actually the liver and explains why HH patients suffer from increased iron absorption.”
HFE encodes a protein that is likely involved in transmitting signals about the current iron contents of the body to liver cells. In response to these signals, the liver cells make a special iron hormone, hepcidin, that is released into the blood stream and reduces iron uptake in the intestine.
“HFE influences hepcidin expression through a series of intermediate molecules, but when the HFE gene is mutated the result is that less hepcidin is produced. This in turn means iron uptake in the intestine cannot be limited as effectively and an overload develops,” says Martina Muckenthaler, professor at the University of Heidelberg.
Public Release: 7-Feb-2008
Sleep Duration May Play Important Role in Childhood Obesity
Less sleep can increase a child’s risk of being overweight or obese, according to a study by researchers at the Johns Hopkins Bloomberg School of Public Health. Their analysis of epidemiological studies found that with each additional hour of sleep, the risk of a child being overweight or obese dropped by 9 percent. The results are published in the February 2008 edition Obesity, the journal of The Obesity Society.
“Our analysis of the data shows a clear association between sleep duration and the risk for overweight or obesity in children. The risk declined with more sleep,” said Youfa Wang, MD, PhD, senior author of the study and associate professor with the Bloomberg School’s Center for Human Nutrition. “Desirable sleep behavior may be an important low cost means for preventing childhood obesity and should be considered in future intervention studies. Our findings may also have important implications in societies where children do not have adequate sleep due to the pressure for academic excellence and where the prevalence of obesity is rising, such as in many East Asian countries.”
“The influence of sleep quality on obesity risk is another important area where future research is needed,” added Xiaoli Chen, MD, PhD, the study’s lead author and a former postdoctoral fellow at the Bloomberg School.
For the study, Wang, Chen and colleague May A. Beydoun, also a postdoctoral fellow at the Bloomberg School, reviewed 17 published studies on sleep duration and childhood obesity and they analyzed 11 of them in their meta-analysis.
The recommended amount of daily sleep varied between studies analyzed and with children’s age. Some research suggests that children under age 5 should sleep for 11 hours or more per day, children age 5 to 10 should sleep for 10 hours or more per day, and children over age 10 should sleep at least 9 hours per day. The Hopkins researchers used these suggestions for their analysis.
The results of the analysis showed that children with the shortest sleep duration had a 92 percent higher risk of being overweight or obese compared to children with longer sleep duration. For children under age 5, shortest sleep duration meant less than 9 hours of sleep per day. For children ages 5 to 10 it meant less than 8 hours of sleep per day and less than 7 hours of sleep per day for children over 10. The association between increased sleep and reduced obesity risk was strongly associated with boys, but not in girls.
Public release date: 7-Feb-2008
Study suggests new therapy for lung disease patients (Current Therapy Wrong)
CHICAGO — A new study by researchers at Northwestern University’s Feinberg School of Medicine may change current thinking about how best to treat patients in respiratory distress in hospital intensive care units.
It has been commonly believed that high levels of carbon dioxide (CO2) or hypercapnia in the blood and lungs of patients with acute lung disease may be beneficial to them. Now, for the first time, scientists have shown how elevated levels of CO2 actually have the opposite effect.
The excessive CO2 impairs the functioning of the lungs. Jacob Sznajder, M.D., chief of pulmonary and critical care at the Feinberg School, and his research team found that high levels of CO2 make it harder for the lungs to clear fluid.
The excess CO2 initiates a signaling cascade leading to the inhibition of the action of sodium “pumps” that help move water out of the air spaces. This creates a greater risk of edema in which the lungs flood with fluid.
The investigators worked with rats and human cells for the study, which was published in the February issue of the Journal of Clinical Investigation.
“Allowing high levels of CO2 may contribute to the high mortality of patients with diseases like chronic obstructive pulmonary disease (COPD),” said Sznajder, a professor of medicine and of cell and molecular biology at the Feinberg School and a physician at Northwestern Memorial Hospital. “This study argues toward therapies to reduce the high CO2 levels of patients toward normal levels, which is not the current practice in the intensive care unit.”
COPD is the fourth leading cause of death in the United States, killing more than 120,000 people, according to the National Institutes of Health. When people have COPD, their lungs lose elasticity and have trouble exchanging carbon dioxide for oxygen. COPD used to be strictly a disease of smokers, but now it’s also crippling the lungs of non-smokers.
Public release date: 11-Feb-2008
Anti-cancer drug damages brain vessels
The cancer drug Avastin (bevacizumab) is used to treat advanced bowel cancer in combination with chemotherapy. This drug targets a protein called VEGF (vascular endothelial growth factor) that stimulates blood vessel growth. Avastin inhibits the growth of tumors by cutting off their blood supply, which deprives them of oxygen and other nutrients. In a small percentage of patients, however, Avastin can cause neurological side effects ranging from headaches and blurry vision to potentially fatal seizures and brain swelling.
The new study reveals that VEGF normally protects the specialized cells that create a seal between the brain and spinal column and thus prevent fluid from leaking into the brain. When VEGF was blocked in mice, these cells died and the animals developed brain swelling. The authors suspect that Avastin’s side effects in humans may be caused by a similar phenomenon. Why these symptoms occur in only a few patients is not yet known.
Public release date: 11-Feb-2008
Fatty acids beneficial in treatment for dry eye syndrome
Boston (Feb. 11, 2008) — Research conducted by Massachusetts Eye and Ear Infirmary (MEEI) Cornea Service Director and Harvard Medical School Professor Reza Dana, M.D., M. Sc., MPH, and colleagues at the Schepens Eye Research Institute have found for the first time that topical drop application of alpha-linolenic acid (ALA) led to a significant decrease in clinical signs of dry eye syndrome (DES) in animal models. ALA is a fatty acid that cannot be made by the body and must be supplied in the diet. The study will be published in the February 2008 issue of Archives of Ophthalmology.
Dry eye syndrome is a condition in which the eyes do not produce enough tears, causing them to become dry and irritated. Inflammation is frequently associated with the condition. Symptoms of dry eye syndrome include eye discomfort, such as stinging or burning, eye irritation or a feeling of scratchiness. The condition affects well more than 10 million people, primarily women, in the United States alone and can often lead to problems with activities such as reading and driving. Dry eye syndrome is also one of the most common conditions for which patients see eye care. Unfortunately, treatment options are quite limited in terms of both efficacy and undesirable side-effects.
The study tested three formulations of fatty acids: 0.2 percent alpha-linolenic acid (an omega-3 fatty acid) ; 0.2 percent linoleic acid (an omega-6 fatty acid) ; and 0.1 percent alpha-linolenic acid combined with 0.1 percent linoleic acid. An eye drop containing each of the three formulations was applied topically to the eye of a mouse once daily. An untreated group did not receive eye drops. Signs of dry eye were then measured 24 hours after the last dose. Eyes treated with ALA showed a significant reversal in epithelial damage to the cornea, the transparent dome that covers the pupil. Results show a beneficial effect of the topical application of ALA in reversing the signs of dry eye syndrome as well as the inflammatory changes seen in dry eye syndrome.
“The current study for the first time demonstrates the benefit of topical application of a particular fatty acid in treating the signs of dry eye syndrome at both the molecular and cellular levels. Using topical formulations of fatty acids to treat dry eye would allow for more flexibility for treatment, including lessening side effects that patients can experience from oral intake of fatty acids. Clinical studies with topical fatty acids are being planned, which if successful could alter the method by which this common condition is treated,” said Dr. Dana.
Public release date: 11-Feb-2008
Purple pigments and obesity
Journal of Agricultural and Food Chemistry
Scientists in Arkansas are reporting new evidence that natural pigments responsible for the beautiful blue/purple/reddish color of certain fruits and vegetables may help prevent obesity. Their animal study, scheduled for the Feb. 13 issue of ACS’ Journal of Agricultural and Food Chemistry, however, reports that eating the whole fruit containing these pigments seems to be less effective than eating an extract of the berry.
Ronald L. Prior and colleagues, who did the new study, note that past research has shown that the pigments — called anthocyanins — prevent obesity in laboratory mice fed a high-fat diet. Anthocyanins are found in grape skins, blueberries, blackberries, purple corn, and other foods. The mice also had other healthful changes in disease-related substances found in the blood.
In the new study, researchers found that mice fed a high-fat diet for 8 weeks plus drinking water with purified anthocyanins from blueberries and strawberries gained less weight and had lower body fat levels than a control group. “Anthocyanins fed as the whole blueberry did not prevent and may have actually increased obesity,” the study reported. “However, feeding purified anthocyanins from blueberries or strawberries reduced obesity.” — JS
Public release date: 11-Feb-2008
Fake malaria drugs made in China; how the winter vomiting virus evolves
Study finds evidence of fake malaria drugs being manufactured in China
A unique collaborative study between scientists, public health workers and police has led to the arrest of alleged traders of fake anti-malarial drugs in China. The epidemiological investigation, involving teams from across the globe and published in this week’s PLoS Medicine, highlights the growing threat posed by fake pharmaceuticals and the complexities of tracking down those responsible for their manufacture.
Fake anti-malarial drugs are an increasingly serious problem, particularly in South East Asia and Africa. In countries such as Myanmar (Burma), the Lao PDR, Cambodia and Viet Nam, with a large burden of malaria, as many as half of all purchased artesunate tablets, one of the most effective of anti-malarial drugs, are counterfeit.
The new collaborative investigation, known as “Operation Jupiter,” was coordinated by the International Criminal Police Organisation (INTERPOL), the World Health Organization’s Western Pacific Regional Office, and the Wellcome Trust-University of Oxford SE Asian Tropical Medicine Research Programme, in close cooperation with Chinese authorities. Scientists from five other laboratories analysed the composition of 391 samples of genuine and fake artesunate tablets collected across SE Asia, and also studied their packaging.
Most of the fakes examined contained no artesunate. Some contained a wide range of potentially toxic wrong active ingredients, including banned pharmaceuticals such as metamizole, and raw materials, such as safrole, used for the manufacture of the drug ecstacy.
Of additional great concern for public health, the counterfeiters sometimes included dangerously small amounts of artesunate in the tablets. This may be done to foil screening tests of drug quality, but these doses are too low to be effective at treating malaria yet high enough to encourage the spread of malaria parasites resistant to the medicine.
Dr Paul Newton (Wellcome Trust-University of Oxford SE Asian Tropical Medicine Research Programme), the study’s lead author, said: “Artesunate, as part of artemisinin-based combination therapy, is vital for malaria treatment and is one of the most effective weapons we have against this terrible scourge.”
“Those who make fake anti-malarials have killed with impunity,” he said, “directly through the criminal production of a medicine lacking active ingredients and by encouraging drug resistance to spread. If malaria becomes resistant to artesunate, the effect on public health in the tropics will be catastrophic.”
In addition to analysing the chemistry of the samples, researchers used a technique known as forensic palynology to study pollen contamination within the fake tablets with the aim of tracking down the likely location of manufacture. The pollen evidence suggested that at least some of the counterfeit artesunate came from southern China, and this was supported by examination of the mineral calcite, found in some of the samples.
Armed with these findings by INTERPOL, Chinese authorities arrested a suspect in China’s Yunnan Province in 2006. He is alleged to have traded 240,000 blisterpacks of counterfeit artesunate, enough to “treat” almost a quarter of a million adults with a medicine with no activity against a potentially fatal disease. Whilst the Chinese authorities were able to seize 24,000 of these packs, the remainder are alleged to have been sold at crossings on the border of Yunnan and Myanmar (Burma), accounting for almost a half of all blisterpacks of artesunate sold to the region.
Ralph’s Note – Inspect, Inspect, Inspect. In addition if the drug, supplement, or food, is traded across national borders, extradite.
Public release date: 11-Feb-2008
Autopsy findings suggest end of decline in coronary disease rates
Autopsies of individuals in one Minnesota County suggest that the decades-long decline in the rate of coronary artery disease may have ended and possibly reversed after 2000, according to a report in the February 11 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
“Over the past century, the rate of death due to heart disease in the United States rose until the mid 1960s when it began a steady decline, which continues today,” the authors write as background information in the article. These declines appear to be accompanied by reductions in the incidence and death rates of coronary artery disease, the most common form of heart disease, characterized by blockages in the vessels that supply blood to the heart. The gold standard for detecting trends in the prevalence of coronary artery disease among the general population has been gathering information from autopsies. However, autopsy rates must be high to ensure that findings accurately reflect the general population. The national autopsy rate has never been high and continues to decline, with a national average of only 8.3 percent in 2003.
Olmsted County, Minnesota, has traditionally had high autopsy rates across all age groups. Rates are especially high for non-elderly individuals who died of unnatural causes (such as accidents, homicides or suicides). Cynthia Leibson, Ph.D., and colleagues from Mayo Clinic, Rochester, Minn., and the University of British Columbia, Vancouver, Canada, used data from death certificates and pathology reports to assess trends in coronary artery disease among Olmsted County residents age 16 through 64 who died of unnatural causes between 1981 and 2004.
A total of 3,237 Olmsted County residents in this age group died in those years, 515 of unnatural causes. Among those 515, 96 percent were autopsied and 82 percent (425) had grades assigned based on the amount of blockage in several coronary arteries, with grades ranging from zero (no blockage) to five (100 percent blocked).
“Over the full period (1981 to 2004), 8.2 percent of the 425 individuals had high-grade disease, and 83 percent had evidence of any disease,” the authors write. High-grade disease was defined as a grade of three or higher in the left main artery or a grade four or higher in any other single artery. Analyses adjusted to consider the individuals’ age and sex revealed declines over the entire period for high-grade disease, any disease and the average grade of disease. However, “declines in the grade of coronary disease ended after 1995 and possibly reversed after 2000.”
“Our finding that temporal declines in the grade of coronary artery disease at autopsy have ended, together with suggestive evidence that declines have recently reversed, provides some of the first data to support increasing concerns that declines in heart disease mortality may not continue,” the authors conclude. “The extent to which recent trends are attributable to the epidemics of obesity and diabetes mellitus awaits further investigation.”
Public release date: 11-Feb-2008
Study finds patients with complex fibroadenomas can avoid surgery
Complex fibroadenomas have a low incidence of malignancy, so women with this condition can be more conservatively treated and avoid surgical biopsy, according to a new study by a team of researchers from the Hadassah-Hebrew University Medical Center in Jerusalem.
A fibroadenoma is a benign growth of the breast that is common in young women. They are not usually associated with breast cancer, and are often diagnosed with simple ultrasound-guided, non-surgical biopsy. Complex fibroadenomas are a subtype of fibroadenomas. They are also benign, but they have calcifications and small cysts that make their pathology more complex than simple fibroadenomas, prompting many doctors to recommend surgical removal to ensure that the fibroadenoma is not malignant.
“There is a lack of information or guidelines in the medical literature about the management of complex fibroadenomas, causing a dilemma for doctors with patients who have these lesions. Because the management of these patients is not clear, there is a tendency to excise them on surgery following a needle biopsy,” said Miri Sklair-Levy, MD, lead author of the study.
For the study, the researchers evaluated the clinical and imaging presentations of biopsy-proven complex fibroadenomas in 63 patients, compared pathologies and sizes of the lesions, and then followed up after two years. They found that only one out of the 63 patients with complex fibroadenomas had a malignancy, and that the patient with a malignancy had already shown previously.
“The findings from our study showed that complex fibroadenomas can be treated similar to simple fibroadenomas, meaning follow-up without the need to excise the lesions surgically. The exception to this practice would be if some atypical high-risk lesions are found, as in the case with the one patient in our study. In those situations, the complex fibroadenomas should be surgically excised to rule out malignancy,” said Dr. Sklair-Levy.
Public release date: 11-Feb-2008
Some cases of autism may be traced to the immune system of mothers during pregnancy
SACRAMENTO, Calif.) – New research from the UC Davis M.I.N.D. Institute and Center for Children’s Environmental Health has found that antibodies in the blood of mothers of children with autism bind to fetal brain cells, potentially interrupting healthy brain development. The study authors also found that the reaction was most common in mothers of children with the regressive form of autism, which occurs when a period of typical development is followed by loss of social and/or language skills. The findings, to be published in the March 2008 issue of Neurotoxicology, raise the possibility that the transfer of maternal antibodies during pregnancy is a risk factor for autism and, at some point, that a prenatal test and treatment could prevent the disorder for some children.
“While a growing body of research is dedicated to finding distinctions in the immune systems of children with autism, this is one of the first studies to identify immunological factors in mothers that could be linked to autism in the very earliest stages of life,” said Judy Van de Water, senior author of the study and professor of rheumatology, allergy and clinical immunology. “Our results should lead to more research on the prenatal environment and the onset of autism. We are also optimistic that in the future a prenatal test and therapeutic intervention preventing IgG exposure during pregnancy could protect some children from ever getting autism.”
We’re not entirely sure why the IgG response against fetal brain proteins was so specific for later onset autism,” said Van de Water. “It’s possible that early exposure to maternal antibodies sets in motion a biological path to autism with the behavioral outcomes not apparent until much later. It’s also possible that an environmental exposure sometime after birth could be required to set this process in motion. We are hopeful that this study will help build our understanding of the foundations of the regressive form of the disorder.”
Characteristic features of autism – social deficits, language impairments and limited, repetitive behaviors – are often clear early in an affected child’s life. Other children seem to progress normally until 12-to-24 months of age, when developmental milestones disappear. These distinct pathways have led clinicians to identify autism as one of two types – early onset or regressive – potentially with distinct causes and disease processes.
IgG antibodies are responsible for long-term immune system responses to infection, but they can also contribute to autoimmune diseases such as arthritis, multiple sclerosis and lupus. IgG also crosses the placenta in order to provide key immune system protectants to a growing fetus and newborn child, which is a key reason why Van de Water decided to investigate the role of IgG as a potential factor in autism.
Van de Water next wants to know if IgG in women during the time of their pregnancies produces the same response to fetal brain proteins. Women in the current study were two-to-five years beyond childbirth. She will now conduct the same study with women who are pregnant and already have a child with autism, because such women are much more likely to have another child with the disorder.
Public release date: 13-Feb-2008
A compound extracted from olives inhibits cancer cells growth and prevents their appearance
A research group of the University of Granada has found out that maslinic acid, a compound present in the leaf and the olive skin wax extracted from alpeorujo (crushed olive pulp), has the capacity of preventing cancer as well as regulating apoptosis in carcinogenic processes.
Maslinic acid is a protease inhibitor that, among other features, has the capacity of regulating cell growth. It is useful for cancer treatment, as it allows to control the hyperplasia and hypertrophy processes, typical of this disease. The scientists of the UGR have characterized for the first time maslinic acid action from the molecular point of view when it is applied to the development of tumour cells.
This work has been carried out by Ph D student Fernando Jesús Reyes Zurita, and directed by Professor José Antonio Lupiáñez Cara, of the department of Biochemistry and Molecular Biology I. According to them, the advantages of maslinic acid are three: Unlike other anti-carcinogenic products, highly cytotoxic, it is a natural compound and, therefore, less toxic. In addition, it is selective, this is, it only acts on carcinogenic cells, whose pH is more acid than usual. And lastly, it has a preventive nature, as it can inhibit cancer appearance in those cells with a higher predisposition to develop it.
For all types of cancer
Although the research group of Professor Lupiáñez Cara has analysed the effect of maslinic acid in the treatment of colon cancer, it can be used in different types of tumours. For the moment, their research works have been developed in colon carcinoma lines and transgenic mice, but they have not dismissed the possibility of applying them to humans in future.
Maslinic acid is a pentacyclic terpene which, besides being anti-carcinogenic, it has anti-inflammatory and antioxidant effects and can be found in high concentrations in olive skin wax. At present, the only production plant of this substance at a semi-industrial level in the whole world is at the Faculty of Sciences of the University of Granada.
Public release date: 13-Feb-2008
U of I study: exercise to avoid gallstones!
University of Illinois study shows that exercise-trained mice get far fewer gallstones than sedentary mice and identifies potential mechanisms to explain why this occurs.
The study, recently published in the Journal of Applied Physiology, can be viewed online at: http://jap.physiology.org/cgi/reprint/01292.2007v1.
“For the first time, we have direct evidence that physical activity reduces gallstone formation, adding to the ever-increasing number of reasons that people should get more exercise,?said Kenneth Wilund, a faculty member in the U of I Division of Nutritional Sciences and an Assistant Professor in Kinesiology and Community Health.
Gallbladder disease affects 10 to 25 percent of adults in the United States, although some persons who are affected may not have symptoms. It has the second highest cost of any digestive disease at $5.8 billion annually and results in over 800,000 hospitalizations each year.
Gallstones form when bile cholesterol levels become high enough to precipitate, fall out of solution, and solidify, Wilund said.
In the study, 50 mice from a gallstone-susceptible strain were fed a high-fat diet containing cholic acid, which helps increase cholesterol absorption. They were then divided into two groups. One group of mice ran on treadmills 45 minutes per day five days a week; the other group did not exercise.
After 12 weeks, the scientists removed the animals?gallbladders, pooling the stones from each group and weighing them. The gallstones in the sedentary group weighed two and a half times more than the stones in the exercised group.
“You could see through the gallbladders in the exercise-trained group, whereas the gallbladders in the sedentary group were full of stones,?Wilund said.
To understand more about why this happened, the scientists then measured the expression of selected genes in the liver and intestine that are involved in cholesterol absorption and may affect gallstone development.
“In the exercised mice, we saw an increase in the expression of two genes (LDLr and SRB1) that help bring cholesterol into the liver to ‘clear?it from the circulation. But we also found that a protein called Cyp27 was upregulated about two a half times; this resulted in there being more bile acids to solubilize the increased cholesterol so it didn’t turn into gallstones.
“Taken together, the differences in gene expression between the exercised and sedentary mice in this study show how exercise training could simultaneously improve cholesterol levels while also inhibiting gallstone formation,?he said.
Previous observational studies have suggested that people who are physically fit have fewer gallstones and lower cholesterol, but laboratory studies had not confirmed the link.
Wilund said these mice are a useful model because humans have a similar set of genes that regulate liver and bile cholesterol metabolism. He also said that human studies would be difficult to perform because of the number of years it takes for people to develop gallstones.
“We certainly found the changes in gene expression in the exercised animals very intriguing,?he said. “The results add to a body of evidence that supports the importance of physical activity for good health.?/
Public release date: 14-Feb-2008
Metabolic syndrome linked to cold tolerance
Researchers from the University of Chicago have discovered that many of the genetic variations that have enabled human populations to tolerate colder climates may also affect their susceptibility to metabolic syndrome, a cluster of related abnormalities such as obesity, elevated cholesterol levels, heart disease, and diabetes.
More than 100 years ago, scientists noted that humans inhabiting colder regions were bulkier and had relatively shorter arms and legs. In the 1950s, researchers found correlations between colder climates and increased body mass index (BMI), a measure of body fat, based on height and weight.
Now, in a study published in the February issue of the open-access journal PLoS Genetics, scientists have found a strong correlation between climate and several of the genetic variations that appear to influence the risk of metabolic syndrome, consistent with the idea that these variants played a crucial role in adaptations to the cold. The researchers report that some genes associated with cold tolerance have a protective effect against the disease, while others increase disease risk.
“Our earliest human ancestors lived in a hot humid climate that placed a premium on dispersing heat,” said Anna Di Rienzo, professor of human genetics at the University of Chicago. “As some populations migrated out of Africa to much cooler climates, there would have been pressure to adapt to their new settings by boosting the processes that produce and retain heat.”
“Thousands of years later,” she said, “in an era that combines widespread central heating with an overabundant food supply, those genetic alterations have taken on a different sort of significance. They alter our susceptibility to a whole new set of diseases, such as obesity, coronary artery disease and type 2 diabetes.”
The researchers set out to look for correlations between the frequency of genetic variations linked to metabolic syndrome and climate variables in worldwide population samples.
They selected 82 genes associated with energy metabolism – many of them previously implicated in disease risk – and looked for climate-related variations in those genes. They studied genetic variation in 1,034 people from 54 populations, finding widespread correlations between the frequencies of certain genetic variations and colder climates, as measured by latitude as well as summer and winter temperatures.
One of the strongest signals of selection came from the leptin receptor, a gene involved in the regulation of appetite and energy balance. One version of this gene is increasingly common in locales with colder winters. This version of the leptin receptor is associated with increased respiratory quotient – the ability to take up oxygen and release carbon dioxide – which plays an important role in heat production. This allele also has been linked to lower BMI, less abdominal fat and lower blood pressure, and is thus protective against metabolic syndrome.
Other genes that varied according to climate included several involved in heat production, cholesterol metabolism, energy use, and blood glucose regulation.
Not all cold-tolerance-related gene variants protect against metabolic syndrome. Increased blood glucose levels, for example, could protect someone from the cold by making fuel more readily available for heat production, yet it raises the risk of type 2 diabetes. The version of a gene known as FABP2 that became more common as temperatures fell causes increased BMI, promotes fat storage and elevates cholesterol levels. This would protect against the cold, but increase susceptibility to heart disease and diabetes.
“All these genes are likely to be involved in metabolic adaptations to cold climates,” said Di Rienzo, “but they have opposing effects on metabolic syndrome risk. We suspect they spread rapidly as populations settled into colder and colder climates at higher latitudes, but in the modern era they have taken on a whole new significance, as the supply of calories from food has mushroomed and the survival advantage of generating more heat has been minimized by technology.”
The authors suggest that the search for genes that vary according to climate could provide additional clues about the onset of metabolism related diseases.
“The biological processes that influence tolerance to climatic extremes,” the authors conclude, “are likely to play important roles in the pathogenesis of common metabolic disorders… Our results argue for a role of climate adaptations in the biological processes underlying the metabolic syndrome and its phenotypes.”
Public release date: 14-Feb-2008
Cell phone-cancer link found by Tel Aviv University scientist
An Israeli scientist, Dr. Siegal Sadetzki, has found a link between cell phone usage and the development of tumors.
Dr. Sadetzki, a physician, epidemiologist and lecturer at Tel Aviv University, published the results of a study recently in the American Journal of Epidemiology, in which she and her colleagues found that heavy cell phone users were subject to a higher risk of benign and malignant tumors of the salivary gland.
Those who used a cell phone heavily on the side of the head where the tumor developed were found to have an increased risk of about 50% for developing a tumor of the main salivary gland (parotid), compared to those who did not use cell phones.
The fact that the study was done on an Israeli population is significant. Says Sadetzki, “Unlike people in other countries, Israelis were quick to adopt cell phone technology and have continued to be exceptionally heavy users. Therefore, the amount of exposure to radiofrequency radiation found in this study has been higher than in previous cell phone studies.
“This unique population has given us an indication that cell phone use is associated with cancer,” adds Sadetzki, whose study investigated nearly 500 people who had been diagnosed with benign and malignant tumors of the salivary gland.
Controlled Study Reveals Link
The study’s subjects were asked to detail their cell phone use patterns in terms of how frequently they used one, and the average length of calls. They were compared to a sample of about 1,300 healthy control subjects.
The study also found an increased risk of cancer for heavy users who lived in rural areas. Due to fewer antennas, cell phones in rural areas need to emit more radiation to communicate effectively.
Sadetzki predicts that, over time, the greatest effects will be found in heavy users and children.
While anecdotal evidence has been substantial, the consistency of the results of this study support an association between cell phone use and these tumors. The risks have been hard to prove, mainly due to the long latency period involved in cancer development, explains Sadetzki.
Keep Calling but Call Smarter
Today it is estimated that more than 90% percent of the Western world uses cell phones. As the technology becomes cheaper and more accessible, its usage by a greater number of people, including children, is bound to increase.
“While I think this technology is here to stay,” Sadetzki says, “I believe precautions should be taken in order to diminish the exposure and lower the risk for health hazards.” She recommends that people use hands-free devices at all times, and when talking, hold the phone away from one’s body. Less frequent calls, shorter in duration, should also have some preventative effect.
While she appreciates the ease of communication that cell phones allow between parents and their children, Sadetzki says that parents need to consider at what age their children start using them. Parents should be vigilant about their children’s using speakers or hands-free devices, and about limiting the number of calls and amount of time their children spend on the phone.
“Some technology that we use today carries a risk. The question is not if we use it, but how we use it,” concludes Sadetzki.
Sadetzki’s main research on this new study was carried out at the Gertner Institute for Epidemiology and Health Policy Research at the Sheba Medical Center. Her research is part of the international Interphone Study, which attempts to determine an association between cell phones and several types of brain and parotid gland tumors.
Public release date: 16-Feb-2008
Health effects of pesticide mixtures: Unexpected insights from the salmon brain
In his research, scientist Nat Scholz examines how pesticides that run off the land and mix in rivers and streams combine to have a greater than expected toxic effect on the salmon nervous system. These pesticides are widely used in the United States and their occurrence as mixtures in the food supply for humans may also pose an unexpected risk for people.
“We have a pretty good handle on how to assess the health effects of single chemicals in conventional toxicity trials,” said Scholz, a fishery biologist with the National Oceanic and Atmospheric Administration. “But the real world is usually more complex, and exposures to mixtures of chemicals can be more of the rule than the exception. One of the major scientific challenges of our generation is to develop new approaches to anticipate and head off any ill effects of interacting chemicals.”
Scholz will present his research along with five other scientists from the U.S. government, the Canadian government and academia in the symposium entitled “From Kitchen Sinks to Ocean Basins: Emerging Chemical Contaminants and Human Health.” Organized by NOAA’s Oceans and Human Health Initiative, the symposium is one of the features of the AAAS Annual Meeting.
Scholz and his colleagues found that salmon died when exposed to combinations of pesticides that were not deadly when tested in individual trials. The findings for salmon could have important implications for the recovery of many threatened and endangered salmon populations throughout the western United States. The research also points to the need for more study of how combinations of pesticides found on fruits and vegetables may be affecting humans.
Public release date: 18-Feb-2008
As depression symptoms improve with antidepressants, hopelessness can linger
A sense of hopefulness does not improve as quickly as other symptoms
ANN ARBOR, Mich. — People taking medication for depression typically see a lot of improvements in their symptoms during the first few months, but lagging behind other areas is a sense of hopefulness, according to new research from the University of Michigan Health System.
That means people with depression may still feel a sense of hopelessness even while their condition is improving, which could lead them to stop taking the medication.
For many in the study, feelings of hopefulness did not improve until several weeks, or even months, after depressive symptoms lifted, says lead author James E. Aikens, Ph.D., associate professor in the Department of Family Medicine at the University of Michigan Health System.
“The finding suggests that some patients may become unduly pessimistic and stop adhering to an already-helpful therapy,” he notes. This finding is troubling, he says, because hopelessness is a strong risk factor for suicide.
The study appears in the January-February issue of the journal General Hospital Psychiatry.
Aikens and his team studied 573 patients with depression from 37 practices. They were given an antidepressant, either fluoxetine (Prozac), paroxetine (Paxil) or sertraline (Zoloft). They were assessed one, three, six and nine months after the treatment began.
Overall, patients’ depression responded rapidly to medication, with 68 percent of their improvement occurring by the end of the first month, and 88 percent by three months. The patients experienced the majority of their improvement in several areas during this time period, including positive emotions, work functioning and social functioning.
Improvements in head, back and stomach pain plateaued during the first month, with little improvement thereafter. Because of that, Aikens says, physicians may want to consider additional treatments that directly target pain in depressed patients if these physicial complaints persist after the first few weeks of treatment with antidepressants.
With hopefulness, however, the improvement was much more gradual. Physicians may want to consider cognitive-behavioral strategies, such as teaching patients to identify and challenge the pessimistic thoughts that usually accompany depression, and encouraging them to engage in activities that may improve their mood, Aikens says.
Public release date: 18-Feb-2008
Vaccine doesn’t match most circulating viruses, health officials say
ATLANTA – The flu season is getting worse, and U.S. health officials say it’s partly because the flu vaccine doesn’t protect against most of the spreading flu bugs.
The flu shot is a good match for only about 40 percent of this year’s flu viruses, officials at the U.S. Centers for Disease Control and Prevention said Friday.
That’s worse than last week’s report when the CDC said the vaccine was protective against roughly half the circulating strains. In good years, the vaccine can fend off 70 to 90 percent.
Infections from an unexpected strain have been booming, and now are the main agent behind most of the nation’s lab-confirmed flu cases, said Dr. Joe Bresee, the CDC’s chief of influenza epidemiology.
It’s too soon to know whether this will prove to be a bad flu season overall, but it’s fair to say a lot of people are suffering at the moment. “Every area of the country is experiencing lots of flu right now,” Bresee said.
This week, 44 states reported widespread flu activity, up from 31 last week. The number of children who have died from the flu has risen to 10 since the flu season’s official Sept. 30 start.
Those numbers aren’t considered alarming. Early February is the time of year when flu cases tend to peak. The 10 pediatric deaths, though tragic, are about the same number as was reported at this time in the last two flu seasons, Bresee said.
The biggest surprise has been how poorly the vaccine has performed.
A bad match
Each winter, experts try to predict which strains of flu will circulate so they can develop an appropriate vaccine for the following season. They choose three strains — two from the Type A family of influenza, and one from Type B.
Usually, the guesswork is pretty good: The vaccines have been a good match in 16 of the last 19 flu seasons, experts said.
But the vaccine’s Type B component turned out not to be a good match for the B virus that has been most common this winter. And one of the Type A components turned out to be poorly suited for the Type A H3N2/Brisbane-like strain that now accounts for the largest portion of lab-confirmed cases.
“Typically, they’re very successful at that, but this is just one of those years where it was a little off, and it hasn’t been as good of a match,” John Silcox of the Fort Wayne-Allen County, Ind., Department of Health told WISE-TV in Fort Wayne.
“So that’s why we’re perhaps seeing a little bit more flu.”
Over the years, the H3N2 flu has tended to cause more deaths, Bresee said.
That may be little comfort for the suffering masses. In Philadelphia, Health Commissioner Donald F. Schwarz cited what he called an unusually sharp increase in the number of people with the flu. Emergency room doctors said they were seeing more cases and worse symptoms than last year.
“This year’s been more virulent. People last year had a mild case of the flu and stayed home. This year, they feel a lot more miserable, and we’re treating accordingly,” Dr. Ben Usatch of Lankenau Hospital told WCAU-TV in Philadelphia.
The flu appears to be taking a heavy toll on college students. At the University of Kentucky, in Lexington, doctors have been seeing 20 to 30 students a day with flu symptoms, said Gregory Moore, director of University Health Services. He said conditions on campuses were usually prime for the flu to attack.
“People are living in close proximity,” Moore told WLEX-TV in Lexington. “Unfortunately, some of our students aren’t eating well or sleeping well.”
“I woke up with a fever, started around 101, went up to 103 by the time it was over,” said Elizabeth Shemwell, a student at the university. “Body aches, fever chills, headache, everything. The works — I had it.”
This week, the World Health Organization took the unusual step of recommending that next season’s flu vaccine have a completely different makeup from this year’s. The U.S. Food and Drug Administration is expected to make its decision about the U.S. vaccine next week.
H3N2 strains are treatable by Tamiflu and other antiviral drugs, but the other, H1N1 Type A strains are more resistant. Of all flu samples tested this year, 4.6 percent have been resistant to antiviral medications. That’s up from less than 1 percent last year.
“This represents a real increase in resistance,” Bresee said
Public release date: 18-Feb-2008
FDA ties pneumonia deaths to infant vaccine
WASHINGTON – GlaxoSmithKline Plc’s rotavirus vaccine is associated with increased pneumonia-related deaths and other adverse reactions, U.S. regulatory staff said in documents posted on Friday.
The review comes ahead of a Food and Drug Administration advisory meeting next Wednesday to consider approval of the oral vaccine to prevent the most common cause of severe diarrhea and dehydration among infants and young children in the world.
FDA staff said its analysis of 11 studies revealed that in the largest trial, there was a statistically significant increase in deaths related to pneumonia compared with placebo, documents posted on the FDA’s Web site said.
That study, which enrolled about 63,000 children, also found an increase in convulsions in children given the drug, named Rotarix. Another study found an increased rate of bronchitis, compared with placebo.
In a conclusion section, the FDA documents noted the pneumonia-related deaths and convulsions, but did not appear to make a recommendation to the advisory panel.
That expert panel will weigh the staff review, but makes its own recommendation, which is typically followed by the FDA.
Ralph’s Note- So an Infant has a higher chance of dying from the Vaccine, than a Placebo. Why are they even considering approving this vaccine for global use?