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'Moonlighting' Molecules Discovered; Researchers Uncover New Kink In Gene Control

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Since the completion of the human genome sequence, a question has baffled researchers studying gene control: How is it that humans, being far more complex than the lowly yeast, do not proportionally contain in our genome significantly more gene-control proteins?Now, a collaborative effort at the Johns Hopkins School of Medicine to examine protein-DNA interactions across the whole genome has uncovered more than 300 proteins that appear to control genes, a newly discovered function for all of these proteins previously known to play other roles in cells. The results, which appear in the October 30 issue of Cell, provide a partial explanation for human complexity over yeast but also throw a curve ball in what we previously understood about protein functions.

"Everyone knows that transcription factors bind to DNA and everyone knows that they bind in a sequence-specific manner," says Heng Zhu, Ph.D., an assistant professor in pharmacology and molecular sciences and a member of the High Throughput Biology Center. "But you only find what you look for, so we looked beyond and discovered proteins that essentially moonlight as transcription factors."

The team suspects that many more proteins encoded by the human genome might also be moonlighting to control genes, which brings researchers to the paradox that less complex organisms, such as plants, appear to have more transcription factors than humans. "Maybe most of our genes are doing double, triple or quadruple the work," says Zhu. "This may be a widespread phenomenon in humans and the key to how we can be so complex without significantly more genes than organisms like plants."

The team set out to figure out which proteins encoded by the genome bind to which DNA sequences. It had been predicted by examining the human genome sequence that about 1,400 to 1,700 of encoded proteins are so-called transcription factors -- proteins that bind to specific sequences in DNA to turn a gene on or off. The researchers also included in their study, in addition to these proteins, other types that are known to maintain chromosome structure and bind to structurally different RNA. Also included were proteins that normally relay information within a cell and are not thought to directly come in contact with DNA. In total, they collected nearly 4,200 human proteins together on a protein microarray, or protein "chip."

To identify proteins on that chip that bound DNA directly, the group first reviewed previously published scientific literature and catalogued 460 different, short sequences of DNA that are known or predicted to bind proteins.

One at a time, the team tested each of the 460 DNA sequences against the 4,200 protein-containing chip. In addition to finding many protein-DNA interactions for transcription factors, some confirming previously known interactions, the team found 367 new unconventional DNA binding proteins -- proteins known to do other cellular jobs.

"This nearly doubled the number of known protein-DNA interactions," says Jiang Qian, Ph.D., an assistant professor of ophthalmology at Hopkins. "But we only looked at about a fifth of all the proteins in the human genome -- there could be hundreds, even thousands more of these unconventional transcription factors that we don't yet know about."

One of the unconventional transcription factors discovered was the protein MAP Kinase 1, also known as ERK2, a protein long studied for its ability to control cell growth and development via its ability to add phosphate groups to other molecules.

"It's one of the best studied proteins out there, but no one ever thought ERK2 could directly regulate gene expression by actually binding to DNA," says Seth Blackshaw, Ph.D., an assistant professor of neuroscience and a member of the High Throughput Biology Center and the Neuroregeneration Program at the Institute for Cell Engineering.

To be certain that ERK2 really does bind DNA and control genes in living cells, the team tested the protein in human cells. They found that ERK2 mutated to no longer bind DNA causes specific genes to be turned on, while both normal ERK2 and ERK2 that's no longer able to chemically modify proteins turn off those same genes. "It clearly acts to repress specific genes," says Blackshaw. "Maybe this will help clear up some of the puzzles that have arisen in ERK2 experiments over the years."

A central question in understanding how genes are controlled is hich of the 20,000 proteins encoded by our genome act on which segments of DNA. "It's not possible to predict this a priori," Blackshaw says. "Someone has to do the experiment -- because we just don't know enough about how proteins bind to DNA -- patterns have surfaced in this field's 45 year history, but not enough yet to establish any rules."

This study was funded by the National Institutes of Health, a National Eye Institute Vision Core grant, a W. M. Keck Foundation Distinguished Young Investigator in Medical Research Award, a grant from the Ruth and Milton Steinbach Fund and a generous gift from Mr. and Mrs. Robert and Clarice Smith

Authors on the paper are Shaohui Hu, Zhi Xie, Akishi Onishi, Xueping Yu, Lizhi Jiang, Jimmy Lin, Hee-Sool Rho, Crystal Woodard, Hong Wang, Jun-Seop Jeong, Shunyou Long, Xiaofei He, Herschel Wade, Blackshaw, Qian, and Zhu, all of Johns Hopkins.

Bodybuilding With Steroids Damages Kidneys

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Athletes who use anabolic steroids may gain muscle mass and strength, but they can also destroy their kidney function, according to a paper being presented at the American Society of Nephrology's 42nd Annual Meeting and Scientific Exposition in San Diego, CA. The findings indicate that the habitual use of steroids has serious harmful effects on the kidneys that were not previously recognized.Reports of professional athletes who abuse anabolic steroids are increasingly common. Most people know that using steroids is not good for your health, but until now, their effects on the kidneys have not been known. Leal Herlitz, MD (Columbia University Medical Center) and her colleagues recently conducted the first study describing injury to the kidneys following long-term abuse of anabolic steroids. The investigators studied a group of 10 bodybuilders who used steroids for many years and developed protein leakage into the urine and severe reductions in kidney function. Kidney tests revealed that nine of the ten bodybuilders developed a condition called focal segmental glomerulosclerosis, a type of scarring within the kidneys. This disease typically occurs when the kidneys are overworked. The kidney damage in the bodybuilders has similarities to that seen in morbidly obese patients, but appears to be even more severe.

When the bodybuilders discontinued steroid use their kidney abnormalities improved, with the exception of one individual with advanced kidney disease who developed end-stage kidney failure and required dialysis. Also, one of the bodybuilders started taking steroids again and suffered a relapse of severe kidney dysfunction.

The researchers propose that extreme increases in muscle mass require the kidneys to increase their filtration rate, placing harmful levels of stress on these organs. It's also likely that steroids have direct toxic effects on the kidneys. "Athletes who use anabolic steroids and the doctors caring for them need to be aware of the potentially serious risks to the kidney," said Dr. Herlitz.

This study was conducted in the laboratory of Dr. Vivette D'Agati, MD at Columbia Univeristy Medical Center. Study co-authors include Glen Markowitz, MD, Joshua Schwimmer, MD, Michael Stokes, MD, Cheryl Kunis, MD, Vivette D'Agati, MD, (Columbia University Medical Center); Alton Farris, MD, and Robert Colvin, MD (Massachusetts General Hospital).

The study abstract, "Development of FSGS Following Anabolic Steroid Use in Bodybuilders," (TH-PO163) will be presented as part of a Poster Session during the American Society of Nephrology's 42nd Annual Meeting and Scientific Exposition on Oct. 29 in the Scientific Exposition Hall of the San Diego Convention Center in San Diego, CA.

Just One Cigarette Has Harmful Effect On Arteries Of Young Healthy Adults

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Even one cigarette has serious adverse effects on young adults, according to research presented by Dr. Stella Daskalopoulou at the Canadian Cardiovascular Congress 2009, co-hosted by the Heart and Stroke Foundation and the Canadian Cardiovascular Society.Her study found that smoking one cigarette increases the stiffness of the arteries in 18 to 30 year olds by a whopping 25 per cent.

Arteries that are stiff or rigid increase resistance in the blood vessels, making the heart work harder. The stiffer the artery, the greater the risk for heart disease or stroke.

"Young adults aged 20-24 years have the highest smoking rate of all age groups in Canada," says Dr. Daskalopoulou, an internal medicine and vascular medicine specialist at McGill University Health Centre. "Our results are significant because they suggest that smoking just a few cigarettes a day impacts the health of the arteries. This was revealed very clearly when these young people were placed under physical stress, such as exercise."

The study compared the arterial stiffness of young smokers (five to six cigarettes a day) to non-smokers. The median age was 21 years. Arterial measurements were taken in the radial artery (in the wrist), the carotid artery (in the neck), and in the femoral artery (in the groin), at rest and after exercise.

Arterial stiffness in both smokers and non-smokers was measured using a new but well established method called applanation tonometry. Dr. Daskalopoulou introduced the 'arterial stress test' which measures the arteries' response to the stress of exercise. The test is comparable to a cardiac stress test, which measures the heart's response to the stress of exercise.

"In effect we were measuring the elasticity of arteries under challenge from tobacco," explains Dr. Daskalopoulou.

An initial arterial stress test was carried out to establish a baseline measurement for both the non-smokers and the smokers, who were asked not to smoke for 12 hours prior to the test. After the first meeting, smokers returned and smoked one cigarette each and then repeated the stress test. During the final meeting, smokers were asked to chew a piece of nicotine gum prior to the stress test.

Dr. Daskalopoulou found that after exercise the arterial stiffness levels in non-smokers dropped by 3.6 per cent. Smokers, however, showed the reverse: after exercise their arterial stiffness increased by 2.2 per cent. After nicotine gum, it increased by 12.6 per cent. After one cigarette, it increased by 24.5 per cent.

Interestingly, there was no difference in the arterial stiffness measurements between smokers and non-smokers at rest.

"In effect, this means that even light smoking in otherwise young healthy people can damage the arteries, compromising the ability of their bodies to cope with physical stress, such as climbing a set of stairs or running to catch a bus," says Dr. Daskalopoulou. "It seems that this compromise to respond to physical stress occurs first, before the damage of the arteries becomes evident at rest."

"More than 47,000 Canadians will die prematurely each year due to tobacco use, which often starts in the teen years," warns Heart and Stroke Foundation spokesperson Dr. Beth Abramson. "We know that over 90 per cent of teenagers who smoke as few as three to four cigarettes a day may be trapped into a lifelong habit of regular smoking, which typically lasts 35 to 40 years."

Smoking contributes to the build up of plaque in the arteries, increases the risk of blood clots, reduces the oxygen in the blood, increases blood pressure, and makes the heart work harder. Smoking also nearly doubles the risk of ischemic stroke.

Dr. Abramson says this study reinforces the importance of education, prevention programs, and legislation such as the recently passed Bill C-32, Cracking Down on Tobacco Marketing Aimed at Youth Act.

Thyroid Surgery Safe For Older Patients, Study Finds

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Dr. Melanie W. Seybt, endocrine-head and neck surgeon at the Medical College of Georgia, with patient.
Thyroid surgery is safe for older patients, say physicians who found only slight differences in rates of complications and hospital readmissions in a multi-year study."We were pleasantly surprised," says Dr. Melanie W. Seybt, endocrine-head and neck surgeon at the Medical College of Georgia and first author of the study, published in the journal Archives of Otolaryngology -- Head and Neck Surgery. "We suspected older patients might be admitted to the hospital more often, have more complications and more cancer."

But their study of 428 thyroidectomy patients at MCGHealth Medical Center and the Charlie Norwood Veterans Affairs Medical Center between November 2003 and December 2007, including 44 patients over age 65 and 86 between ages 21-35, showed few differences in the two groups.

Surgeons found:

* They could do outpatient surgery in both groups at essentially the same rate, 45.5 percent in the elderly and 51.2 percent in younger patients
* Similar complication rates, with 12.5 percent of older patients having transient problems with low calcium versus 11.1 percent of younger patients.
* The thyroid growth was suspected to be malignant in 4.5 percent of elderly patients and 2.3 percent of younger patients. Final pathology revealed cancer in 27.3 percent of elderly patients and 18.6 percent of older patients.
* Elderly patients had a slightly higher hospital readmission rate -- 4.5 percent versus 1.2 percent -- but readmissions were related to the transient problems with calcium levels not age-related complications.
* Neither group had post-operative bleeding or permanent vocal cord paralysis.

She hopes the findings will decrease concerns among patients and practitioners about the safety of thyroidectomies in the growing elderly population, noting that thorough preoperative screening, important at any age, likely helped minimize adverse reactions in their older patients.

Although thyroid disease tends to be most common in young women, the number of older patients diagnosed with the problem is escalating, Dr. Seybt says, noting that the oldest patient in this study group was 84. With a geriatric population that has increased by 90 percent in the last 30 years, according to the U.S. Census Bureau, the numbers are likely to continue upward.

"A lot of our older patients have other problems, such as heart failure, hypertension and restrictive lung disease, so we are very aggressive about getting medical clearance and optimizing control of their other problems," Dr. Seybt says.

She notes that head and neck surgeries generally have less complications and quicker recoveries than procedures in other parts of the body, such as the abdomen or chest. Low calcium levels are a common complication of thyroid surgery because the adjacent parathyroid glands are typically a little stunned by removal of the thyroid gland, she says. To help avoid problems, patients are routinely placed on a three-week tapering dose of calcium but sometimes still have transient problems, most commonly numbness or tingling around the lips and cramping of the hands and feet. Because of the close proximity to the vocal cords, patients also can have transient or permanent hoarseness.

While its exact cause is unknown, thyroid disease tends to run in families and radiation exposure is believed to be a risk factor for thyroid cancer. The increased availability of quality, non-invasive screening such as ultrasound likely means more cases are being identified at every age, Dr. Seybt says.

Laptop-sized ultrasounds are showing up in many physician offices and thyroid nodules also show up when patients have more sophisticated studies of the head and neck, such as an MRI scan, for other reasons. Patients or their doctors often just feel nodules in the neck although they can be oddly asymptomatic until they grow large enough to impact swallowing and/or breathing. While some of these larger growths are very obvious, those that grow downward into the chest or toward the back can be harder to detect. In older patients, many of the growths likely have been there a while, Dr. Seybt says.

Depending on the size of the growth in patients, surgeons at MCG and the VA will use one of three different approaches. These include a standard, several-inch incision at the base of the neck for the largest growth as well as include minimally invasive thyroidectomy, in which surgeons work through an incision about half the size of the norm, and an endoscopic approach, in which video monitoring and a thin, ultrasonic scalpel reduce incision size another half.

Dr. David Terris, chair of the Department of Otolaryngology-Head and Neck Surgery in the MCG School of Medicine and a pioneer of the minimally invasive approaches, showed in the March 2006 issue of Laryngoscope that the newer, minimally invasive approaches, which reduce the incision size and recovery time, could be used safely in most patients. Dr. Terris is corresponding author on the current study.

Dr. Terris and Sunny Khichi, a senior medical student at MCG, are study co-authors.

Phytochemicals In Plant-based Foods Could Help Battle Obesity, Disease

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The cheeseburger and French fries might look tempting, but eating a serving of broccoli or leafy greens first could help people battle metabolic processes that lead to obesity and heart disease, a new University of Florida study shows.Eating more plant-based foods, which are rich in substances called phytochemicals, seems to prevent oxidative stress in the body, a process associated with obesity and the onset of disease, according to findings published online in advance of the print edition of the Journal of Human Nutrition and Dietetics.

To get enough of these protective phytochemicals, researchers suggest eating plant-based foods such as leafy greens, fruits, vegetables, nuts and legumes at the start of a meal. Using what is known as a phytochemical index, which compares the number of calories consumed from plant-based foods compared with the overall number of daily calories, could also help people make sure they remember to get enough phytochemicals during their regular meals and snacks, said Heather K. Vincent, Ph.D., the lead author of the paper.

"We need to find a way to encourage people to pull back on fat and eat more foods rich in micronutrients and trace minerals from fruits, vegetables, whole grains and soy," said Vincent, an assistant professor in the UF Orthopaedics and Sports Medicine Institute. "Fill your plate with colorful, low-calorie, varied-texture foods derived from plants first. By slowly eating phytochemical-rich foods such as salads with olive oil or fresh-cut fruits before the actual meal, you will likely reduce the overall portion size, fat content and energy intake. In this way, you're ensuring that you get the variety of protective, disease-fighting phytochemicals you need and controlling caloric intake."

The researchers studied a group of 54 young adults, analyzing their dietary patterns over a three-day period, repeating the same measurement eight weeks later. The participants were broken into two groups: normal weight and overweight-obese.

Although the adults in the two groups consumed about the same amount of calories, overweight-obese adults consumed fewer plant-based foods and subsequently fewer protective trace minerals and phytochemicals and more saturated fats. They also had higher levels of oxidative stress and inflammation than their normal-weight peers, Vincent said. These processes are related to the onset of obesity, heart disease, diabetes and joint disease, she added.

"Diets low in plant-based foods affect health over the course of a long period of time," Vincent said. "This is related to annual weight gain, low levels of inflammation and oxidative stress. Those are the onset processes of disease that debilitate people later in life."

Oxidative stress occurs when the body produces too many damaging free radicals and lacks enough antioxidants or phytochemicals to counteract them. Because of excess fat tissue and certain enzymes that are more active in overweight people, being obese can actually trigger the production of more free radicals, too.

Because many phytochemicals have antioxidant properties, they can help combat free radicals, Vincent said. Phytochemicals include substances such as allin from garlic, lycopene from tomatoes, isoflavones from soy, beta carotene from orange squashes and anythocyanins from red wine, among others.

"People who are obese need more fruits, vegetables, legumes and wholesome unrefined grains," she said. "In comparison to a normal-weight person, an obese person is always going to be behind the eight ball because there are so many adverse metabolic processes going on."

Instead of making drastic changes, people could substitute one or two choices a day with phytochemical-rich foods to make a difference in their diets, Vincent said. For example, substituting a cup of steeped plain tea instead of coffee or reaching for an orange instead of a granola bar could increase a person's phytochemical intake for the day without even changing the feeling of fullness. Over time, replacing more pre-packaged snacks with fresh produce or low-sugar grains could become a habit that fights obesity and disease, Vincent said.

"We always want to encourage people to go back to the whole sources of food, the nonprocessed foods if we can help it," Vincent said. "That would be the bottom line for anyone, regardless of age and body size, keep going back to the purer plant-based foods. Remember to eat the good quality food first."

Currently, there are no recommendations for how much of these plant compounds people should be getting each day, says Susanne Talcott, Ph.D., an assistant professor of food science and nutrition at Texas A&M University. Using the phytochemical index could be a good way to come up with these recommendations, she said.

Like Vincent, Talcott also cautions people to try and stick to the whole sources of foods and be wary of processed foods that promise benefits from added plant compounds.

"Consumers should stick with what we have known for decades and eat fresh or frozen fruits and vegetables," she said. "Stick with those kinds of foods rather than reaching out for a tropical wonder pill or juice."

Smart Rat 'Hobbie-J' Produced By Over-expressing A Gene That Helps Brain Cells Communicate

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Over-expressing a gene that lets brain cells communicate just a fraction of a second longer makes a smarter rat, report researchers from the Medical College of Georgia and East China Normal University.Dubbed Hobbie-J after a smart rat that stars in a Chinese cartoon book, the transgenic rat was able to remember novel objects, such as a toy she played with, three times longer than the average Long Evans female rat, which is considered the smartest rat strain. Hobbie-J was much better at more complex tasks as well, such as remembering which path she last traveled to find a chocolate treat.

The report comes about a decade after the scientists first reported in the journal Nature that they had developed "Doogie," a smart mouse that over-expresses the NR2B gene in the hippocampus, a learning and memory center affected in diseases such as Alzheimer's. Memory improvements they found in the new genetically modified Long Evans rat were very similar to Doogie's. Subsequent testing has shown that Doogie maintained superior memory as he aged.

"This adds to the notion that NR2B is a universal switch for memory formation," says Dr. Joe Z. Tsien, co-director of the MCG Brain & Behavior Discovery Institute and co-corresponding author on the paper published Oct. 19 in PLoS One. Dr. Xiaohua Cao at East China Normal University also is a co-corresponding author.

The finding also further validates NR2B as a drug target for improving memory in healthy individuals as well as those struggling with Alzheimer's or mild dementia, the scientists says.

NR2B is a subunit of NMBA receptors, which are like small pores on brain cells that let in electrically-charged ions that increase the activity and communication of neurons. Dr. Tsien refers to NR2B as the "juvenile" form of the receptor because its levels decline after puberty and the adult counterpart, NR2A, becomes more prevalent.

While the juvenile form keeps communication between brain cells open maybe just a hundred milliseconds longer, that's enough to significantly enhance learning and memory and why young people tend to do both better, says Dr. Tsien, the Georgia Research Alliance Eminent Scholar in Cognitive and Systems Neurobiology. This trap door configuration that determines not just how much but how fast information flows is unique to NMBA receptors.

Scientists found that Hobbie-J consistently outperformed the normal Long Evans rat even in more complex situations that require association, such as working their way through a water maze after most of the designated directional cues and the landing point were removed. "It's like taking Michael Jordan and making him a super Michael Jordan," Deheng Wang, MCG graduate student and the paper's first author, says of the large black and white rats already recognized for their superior intellect.

But even a super rat has its limits. For example with one test, the rats had to learn to alternate between right and left paths to get a chocolate reward. Both did well when they only had to wait a minute to repeat the task, after three minutes only Hobbie-J could remember and after five minutes, they both forgot. "We can never turn it into a mathematician. They are rats, after all," Dr. Tsien says, noting that when it comes to truly complex thinking and memory, the size of the brain really does matter.

That's one of the reasons scientists pursue this type of research: to see if increased production of NR2B in more complex creatures, such as dogs and perhaps eventually humans, gets the same results. He also is beginning studies to explore whether magnesium – a mineral found in nuts, legumes and green vegetables such as spinach – can more naturally replicate the results researchers have obtained through genetic manipulation. Magnesium ion blocks entry to the NMDA receptor so more magnesium forces the brain cell to increase expression levels of the more efficient NR2B to compensate. This is similar to how statin drugs help reduce cholesterol levels in the blood by inhibiting its synthesis in the liver.

Scientists created Hobbie-J and Doogie by making them over-express CaMKII, an abundant protein that works as a promoter and signaling molecule for the NMDA receptor, something that likely could not be replicated in humans. In October 2008, they reported in Neuron that they could also safely and selectively erase old and new memories alike in mice by over-expressing CaMKII while the memory was being recalled

"We want to make sure this is a real phenomenon," Dr. Tsien says of the apparent connection between higher levels of NR2B and better memory. "You should never assume that discovery you made in a cell line or a mouse can be translated to other species or systems unless you do the experiments." He adds that the failure of new drugs and other disappointments result from the lack of sufficient scientific evidence.

The transgenic rat has other practical value as well. There is substantial scientific and behavior data already available on rats and because rats are larger, it's easier to do memory tests and record signals from their brain. For example they are strong enough to press levers to get a food reward and their size and comfort level with water means they won't just float aimlessly in a water maze as "fluffy" mice tend to do.

Smoking Bans Reduce Risk Of Heart Attacks Associated With Secondhand Smoke

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Smoking bans are effective at reducing the risk of heart attacks and heart disease associated with exposure to secondhand smoke, says a new report from the Institute of Medicine. The report also confirms there is sufficient evidence that breathing secondhand smoke boosts nonsmokers' risk for heart problems, adding that indirect evidence indicating that even relatively brief exposures could lead to a heart attack is compelling."It's clear that smoking bans work," said Lynn Goldman, professor of environmental health sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, and chair of the committee of experts that wrote the report. "Bans reduce the risks of heart attack in nonsmokers as well as smokers. Further research could explain in greater detail how great the effect is for each of these groups and how secondhand smoke produces its toxic effects. However, there is no question that smoking bans have a positive health effect."

About 43 percent of nonsmoking children and 37 percent of nonsmoking adults are exposed to secondhand smoke in the United States, according to public health data. Despite significant reductions in the percentages of Americans breathing environmental tobacco smoke over the past several years, roughly 126 million nonsmokers were still being exposed in 2000.

A 2006 report from the U.S. Surgeon General's office, The Health Consequences of Involuntary Exposure to Tobacco Smoke, concluded that exposure to secondhand smoke causes heart disease and indicated that smoke-free policies are the most economical and effective way to reduce exposure. However, the effectiveness of smoking bans in reducing heart problems has continued to be a source of debate.

The IOM committee conducted a comprehensive review of published and unpublished data and testimony on the relationship between secondhand smoke and short-term and long-term heart problems. Eleven key studies that evaluated the effects of smoking bans on heart attack rates informed the committee's conclusions about the positive effects of smoke-free policies. The studies calculated that reductions in the incidence of heart attacks range from 6 percent to 47 percent. Given the variations in how the studies were conducted and what they measured, the committee could not determine more precisely how great the effect is. Only two of the studies distinguished between reductions in heart attacks suffered by smokers versus nonsmokers. However, the repeated finding of decreased heart attack rates overall after bans were implemented conclusively demonstrates that smoke-free policies help protect people from the cardiovascular effects of tobacco smoke, the committee said.

The report also provides a detailed discussion of the evidence from animal research and epidemiological studies showing a cause-and-effect relationship between secondhand smoke exposure and heart problems. The committee was not able to determine the exact magnitude of the increased risk presented by breathing environmental tobacco smoke, but noted that studies consistently indicate it increases the risks by 25 percent to 30 percent. Although there is no direct evidence that a relatively brief exposure to secondhand smoke could precipitate a heart attack, the committee found the indirect evidence compelling. Data on particulate matter in smoke from other pollution sources suggest that a relatively brief exposure to such substances can initiate a heart attack, and particulate matter is a major component of secondhand smoke.

The report was sponsored by the U.S. Centers for Disease Control and Prevention. Established in 1970 under the charter of the National Academy of Sciences, the Institute of Medicine provides independent, objective, evidence-based advice to policymakers, health professionals, the private sector, and the public. The National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council make up the National Academies.

Those With Severe H1N1 At Risk For Pulmonary Emboli, Researchers Find

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University of Michigan researchers have found that patients with severe cases of the H1N1 virus are at risk for developing severe complications, including pulmonary emboli, according to a study published today in the American Journal of Roentgenology.A pulmonary embolism occurs when one or more arteries in the lungs become blocked. The condition can be life-threatening. However, if treated aggressively, blood thinners can reduce the risk of death.

“The high incidence of pulmonary embolism is important. Radiologists have to be aware to look closely for the risks of pulmonary embolism in severely sick patients,” said Prachi P. Agarwal, M.D., assistant professor of radiology at the U-M Medical School and lead author of the study.

“With the upcoming annual influenza season in the United States, knowledge of the radiologic features of H1N1 is important, as well as the virus’s potential complications. The majority of patients with H1N1 that undergo chest X-rays have normal radiographs. CT scans proved valuable in identifying those patients at risk of developing more serious complications as a possible result of the H1N1 virus,” says Agarwal.

Working with Agarwal on the research were Ella Kazerooni, M.D., director of U-M’s division of cardiothoracic radiology and professor of radiology and Sandro K. Cinti, clinical assistant professor in U-M’s Department of Internal Medicine. The research included 66 patients diagnosed with the H1N1 flu. Of those, 14 were patients that were severely ill and required Intensive Care Unit admission.

All 66 patients underwent chest X-rays for the detection of H1N1 abnormalities. Pulmonary emboli were seen in CT scans on five of the 14 ICU patients.

Another important finding is that initial chest radiographs were normal in more than half of the patients with H1N1, says Kazerooni.

“These findings indicate that imaging studies would have to be repeated in severely ill patients to monitor disease progression,” said Kazerooni. “It’s important to heighten awareness not only among the radiologists, but also among the referring clinicians.”

There was no outside funding for the research.

The study will be published in the December issue of the AJR.

'ECG For The Mind' Could Diagnose Depression In An Hour

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An innovative diagnostic technique invented by a Monash University researcher could dramatically fast-track the detection of mental and neurological illnesses.Monash biomedical engineer Brian Lithgow has developed electrovestibulography which is something akin to an 'ECG for the mind'. Patterns of electrical activity in the brain's vestibular (or balance) system are measured against distinct response patterns found in depression, schizophrenia and other Central Nervous System (CNS) disorders.

The vestibular system is closely connected to the primitive regions of the brain that relate to emotions and behaviour, so Lithgow saw the diagnostic potential of measuring and comparing different patterns of electrovestibular activity.

Working with psychiatry researchers at Monash University's Alfred Psychiatry Research Centre (MAPrc) in Melbourne, Australia, he tested volunteers and found distinct response patterns, or "biomarkers", that distinguished different CNS diseases from each other and from regular electrovestibular activity.

Monash has teamed up with corporate partner Neural Diagnostics to develop and patent electrovestibulography, or EVestG™. It is hoped the simple, quick and inexpensive screening process for CNS diseases will eventually become standard practice in hospitals around the world.

"The patient sits in a specially designed tilt chair that triggers electrical responses in their balance system. A gel-tipped electrode placed in the individual's ear canal silences interfering noise so that these meaningful electrical responses are captured and recorded," the Monash researcher said. "The responses are then compared to the distinct biomarkers indicative of particular CNS disorders, allowing diagnosis to be made in under an hour."

Neural Diagnostics CEO Dr Roger Edwards said the implications of the new technique were huge.

"This could be one of the most significant inventions ever to come out of Monash. CNS disorders cost upwards of $US2 trillion globally and affect one in four people sometime in their lifetime. At present, diagnosing these conditions is done almost exclusively by qualitative measures, through questions and interviews, and it can take many years for sufferers to be correctly diagnosed," Dr Edwards said.

The technique is already attracting international interest and, if further testing goes to plan, it could be adopted in Australian and overseas hospitals within a few years.

"We are doing the necessary research and development and getting independent expert reports done, but results so far are cause for great optimism," Dr Edwards said.

MAPrc Director Professor Jayashri Kulkarni said, "Engineering and psychiatry are two disciplines that do not usually work together, but here at MAPrc, through our collaboration, we are at the forefront of translating biotechnology into clinical tools for psychiatric practice. While there is more work to be done, electrovestibulography could provide a major breakthrough in the diagnosis of mental illnesses".

New Findings About Brain Proteins Suggest Possible Way To Fight Alzheimer's

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The action of a small protein that is a major villain in Alzheimer's disease can be counterbalanced with another brain protein, researchers at UT Southwestern Medical Center have found in an animal study.The findings, available online in the journal Proceedings of the National Academy of Sciences, suggest a promising new tactic against the devastating illness, the researchers said.

The harmful protein, called beta-amyloid, is found in the brain and, when functioning properly, suppresses nerve activity involved with memory and learning. Its normal function can be likened to a red traffic light, restraining nerve cells from getting overexcited when they receive stimulating signals from neighboring cells. People with Alzheimer's disease, however, accumulate too much beta-amyloid – the traffic light gets stuck on "red" and nerve cells become less responsive.

Another brain protein, called Reelin, acts as a "green light," stimulating nerve cells to respond more strongly to their neighbors' signals.

The new study shows that applying Reelin directly to brain slices from mice prevents excess beta-amyloid from completely silencing nerves.

"If we can identify a mechanism to keep the nerve cells functioning strongly, that might provide a way to fight Alzheimer's disease," said Dr. Joachim Herz, professor of molecular genetics and neuroscience at UT Southwestern and the study's senior author.

In the study, the researchers recorded electrical currents in the mouse hippocampus, an area of the brain associated with learning and memory. From their experiments they determined that Reelin and beta-amyloid interact with the same protein complex, called an NMDA receptor, which plays an important role in coordinating chemical signals between adjacent nerve cells.

They found that Reelin activates and strengthens the response of the NMDA receptor. In the presence of too much beta-amyloid, the receptor migrates into the cell, reducing the cell's sensitivity to incoming signals. By contrast, in strong concentrations of Reelin, the receptor remains active and the cell has the green light to continue receiving normally.

Dr. Herz said the study is especially important because this mechanism involves another protein involved in Alzheimer's called ApoE4, which is the primary risk factor for the most frequent late-onset form of the disease. The receptor that binds to ApeE molecules also binds to Reelin, and is part of the red-light/green-light complex that controls the sensitivity of the NMDA receptors.

"These results imply that Reelin, ApoE and beta-amyloid converge on the same molecular mechanism, which is critical in the Alzheimer's disease process, and Reelin may be a common factor to fight both beta-amyloid and mutated ApoE," Dr. Herz said. "This study establishes a rationale that ApoE receptors have an action that can keep the Alzheimer's disease process at bay by preventing damage in the first place."

The researchers are currently studying the role of ApoE4 in this mechanism. Mimicking or preserving normal Reelin function to stimulate the ApoE receptors might provide a path to stave off the disease, Dr. Herz said.

Other UT Southwestern authors included lead author Dr. Murat Durakoglugil, assistant instructor of molecular genetics; graduate student Ying Chen; Dr. Charles White, professor of pathology; and Dr. Ege Kavalali, associate professor of neuroscience.

The study was funded by the National Institutes of Health, the American Health Assistance Foundation, the Perot Family Foundation and the Humboldt Foundation.

Physicians Bust Myths About Insulin

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People diagnosed with type 2 diabetes often resist taking insulin because they fear gaining weight, developing low blood sugar and seeing their quality of life decline.A study recently completed at UT Southwestern Medical Center suggests that those fears are largely unfounded and that patients and physicians should consider insulin as a front-line defense, as opposed to a treatment of last resort for non-insulin-dependent diabetes.

"We found that those patients who received insulin initially did just as well, if not better, than those who didn't receive insulin," said Dr. Ildiko Lingvay, assistant professor of internal medicine at UT Southwestern and lead author of the study appearing online and in a future issue of Diabetes Care. "This reinforces the idea that insulin treatment is a viable and safe option for patients, even in the very initial stages of their diagnoses.

"There is a myth out in the community, especially among certain ethnicities, that insulin is the last resort, and that somebody started on insulin is going to die," Dr. Lingvay added. "We as physicians are responsible for teaching the patient that that's not the case."

More than 20 million Americans have type 2 diabetes. Obesity, age and lack of exercise all increase the risk for the disease, which is characterized by a progressive loss of insulin-producing beta cells. Diabetes is the single greatest independent risk factor for heart disease, as well as a contributor to a number of other medical problems, including blindness and kidney disease.

The standard initial treatment for type 2 diabetes is a single drug, often metformin, followed by the addition of more oral hypoglycemic agents as needed.

For this study, researchers evaluated the effectiveness of offering insulin-based therapy as an initial treatment option to newly diagnosed type 2 diabetes patients. They compared rates of compliance, satisfaction, effectiveness, safety and quality of life among the patients, who were randomized to receive either the standard triple oral therapy or insulin plus metformin, an oral drug that helps regulate blood sugar levels.

The patients, ranging in age from 21 to 70 years old, had been diagnosed with type 2 diabetes within the past two months. Researchers recruited study participants from Parkland Memorial Hospital or by self-referral to the Clinical Diabetes Research Clinic at UT Southwestern between November 2003 and June 2005.

After enrollment, every participant followed an insulin and metformin regimen for three months. The patients were then randomized to continue taking insulin and metformin or begin the triple oral therapy regimen. All participants were checked monthly for the first four months, at six months after randomization, and every three months thereafter for three years. Of the 58 patients randomized, 24 of the insulin-treated group and 21 of the triple oral therapy group completed the study.

The researchers found that the patients taking insulin plus metformin had fewer low-blood-sugar, or hypoglycemic, events, gained less weight and reported high satisfaction with the insulin.

Dr. Lingvay said she hopes physicians use these findings as the rationale to offer insulin-metformin as the first, rather than last, line of defense.

"Modern medicine uses insulin as a very effective and safe treatment tool," she said. "With the new devices that we're using, giving yourself an insulin shot is not much harder than taking pills."

The data represent the first three years of a six-year study still under way at UT Southwestern. The next step, Dr. Lingvay said, is to begin analyzing how the insulin plus metformin and oral triple therapy regimens affect insulin production in beta cells.

Other UT Southwestern researchers involved in the study included Jaime Legendre, recipient of a Clinical Research Fellowship from the Doris Duke Charitable Foundation; Dr. Polina Kaloyanova, former fellow in endocrinology; Dr. Song Zhang, assistant professor of clinical sciences; and Beverley Adams Huet, assistant professor of clinical sciences.

The study was supported by Novo Nordisk Inc., the National Institutes of Health and the Doris Duke Charitable Foundation.

Exercise Improves Body Image For Fit And Unfit Alike

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Attention weekend warriors: the simple act of exercise and not fitness itself can convince you that you look better, a new University of Florida study finds.People who don't achieve workout milestones such as losing fat, gaining strength or boosting cardiovascular fitness feel just as good about their bodies as their more athletic counterparts, said Heather Hausenblas, a UF exercise psychologist. Her study is published in the September issue of the Journal of Health Psychology.

"You would think that if you become more fit that you would experience greater improvements in terms of body image, but that's not what we found," she said. "It may be that the requirements to receive the psychological benefits of exercise, including those relating to body image, differ substantially from the physical benefits."

The study by Hausenblas and graduate student Anna Campbell is the first to systematically analyze the wide-ranging effects of exercise on body image by examining all intervention studies on the subject until June 2008. From the 57 publications, the researchers found conclusively that exercise buffed up the way people see their bodies regardless of the actual benefits, but the results varied.

Negative body image has grown to almost epidemic proportions in the past 20 years, with as many as 60 percent of adults in national studies saying they don't like the way their bodies look, Hausenblas said.

Americans spend billions of dollars a year for products designed to change their body size and shape, including diet pills and various cosmetic procedures, she said.

"Body dissatisfaction is a huge problem in our society and is related to all sorts of negative behavior including yo-yo dieting, smoking, taking steroids and undergoing cosmetic surgery," she said. "It affects men and women and all ages, starting with kids who are as young as five years old saying they don't like how their bodies look."

The psychological advantages of exercise have been less explored, including the reduction of depression or confidence in body image, compared with the well-researched and understood physical benefits, she said.

The study found no difference in body image improvement between people who met the American College of Sports Medicine guidelines by exercising at least 30 minutes a day five days a week and those who did not, Hausenblas said. The guidelines are considered the minimum amount of exercise needed to receive the health related benefits of physical activity, she said.

"We would have thought that people exercising this amount would have felt better about their bodies than those who did not work out as much," she said.

In other results, the study showed slightly larger benefits from exercise in terms of improving body image for women than men, Hausenblas said.

"We believed the gap would be much bigger, but what could be coming into play is the rise of body image issues among men," she said. "We're seeing more media portrayals of the ideal physique for men rather than the overriding emphasis on women we did in the past."

Age presented another difference, with older people most likely to report enhanced body images from exercise, Hausenblas said. The gap may be explained by the older generation having more concerns about their body image than young people, who tend to exercise more, she said.

While the frequency of exercise mattered for boosting body perceptions, there were no differences for the duration, intensity, length or type of exercise, the study found.

"People who say they have high body dissatisfaction tend to exercise the least, so we wanted to take it a step further and see whether exercise causes people's body image to improve," she said.

Kathleen Martin Ginis, a kinesiology professor at McMaster University in Ontario, Canada, and exercise expert, praised the research. "This is an important study because it shows that doing virtually any type of exercise, on a regular basis, can help people feel better about their bodies," she said. "With such a large segment of the population dissatisfied with their physiques, it's encouraging to know that even short, frequent bouts of lower intensity exercise can improve body image."

Major Improvements Made In Engineering Heart Repair Patches From Stem Cells

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 Dr. Charles
University of Washington (UW) researchers have succeeded in engineering human tissue patches free of some problems that have stymied stem-cell repair for damaged hearts.The disk-shaped patches can be fabricated in sizes ranging from less than a millimeter to a half-inch in diameter. Until now, engineering tissue for heart repair has been hampered by cells dying at the transplant core, because nutrients and oxygen reached the edges of the patch but not the center. To make matters worse, the scaffolding materials to position the cells often proved to be harmful.

Heart tissue patches composed only of heart muscle cells couldn't grow big enough or survive long enough to take hold after they were implanted in rodents, the researchers noted in their article, published last month in the Proceedings of the National Academy of Sciences. The researchers decided to look at the possibility of building new tissue with supply lines for the oxygen and nutrients that living cells require.

The scientists testing this idea are from the UW Center for Cardiovascular Biology and the UW Institute for Stem Cell and Regenerative Medicine, under the guidance of senior author Dr. Charles "Chuck" Murry, professor of pathology and bioengineering. The lead author is Dr. Kelly R. Stevens, a UW doctoral student in bioengineering who came up with solutions to the problems observed in previous grafts. The study is part of a collaborative tissue engineering effort called BEAT (Biological Engineering of Allogeneic Tissue).

Stevens and her fellow researchers added two other types of cells to the heart muscle cell mixture. These were cells similar to those that line the inside of blood vessels and cells that provide the vessel's muscular support. All of the heart muscle cells were derived from embryonic stem cells, while the vascular cells were derived from embryonic stem cells or a variety of more mature sources such as the umbilical cord. The resulting cell mixture began forming a tissue containing tiny blood vessels.

"These were rudimentary blood vessel networks like those seen early in embryonic development," Murry said.

In contrast to the heart muscle cell-only tissue, which failed to survive transplantation and which remained apart from the rat's heart circulatory system, the pre-formed vessels in the mixed-cell tissue joined with the rat's heart circulatory system and delivered rat blood to the transplanted graft.

"The viability of the transplanted graft was remarkably improved," Murry observed. "We think the gain in viability is due to the ability for the tissue to form blood vessels."

Equally as exciting, the scientists observed that the patches of engineered tissue actively contracted. Moreover, these contractions could be electronically paced, up to what would translate to 120 beats per minute. Beyond that point, the tissue patch didn't relax fully and the contractions weakened. However, the average resting adult heart pulses about 70 beats per minute. This suggests that the engineered tissue could, within limits, theoretically keep pace with typical adult heart muscle, according to the study authors.

Another physical quality that made the mixed-cell tissue patches superior to heart muscle-cell patches was their mechanical stiffness, which more closely resembled human heart muscle. This was probably due to the addition of supporting cells, which created connective tissues. Passive stiffness allows the heart to fill properly with blood before it contracts.

When the researchers implanted these mixed celled, pre-vascularized tissue patches into rodents, the patches grew into cell grafts that were ten times larger than the too-small results from tissue composed of heart muscle cells only. The rodents were bred without an immune system that rejects tissue transplants.

Murry noted that these results have significance beyond their contribution to the ongoing search for ways to treat heart attack damage by regenerating heart tissue with stem cells.

The study findings, he observed, suggest that researchers consider including blood vessel-generating and vascular-supporting elements when designing human tissues for certain other types of regenerative therapies unrelated to heart disease.

One of the major obstacles still to be overcome is the likelihood that people's immune systems would reject the stem transplant unless they take medications for the rest of their lives to suppress this reaction. Murry hopes someday that scientists would be able to create new tissues from a person's own cells.

"Researchers can currently turn human skin cells back to stem cells, and then move them forward again into other types of cells, such as heart muscle and blood vessel cells," Murry said. "We hope this will allow us to build tissues that the body will recognize as 'self.'"

While the clinical application of tissues engineered from stem cells in treating hearts damaged from heart attacks or birth defects is still in the future, the researchers believe progress has been made. This study showed that researchers could create the first entirely human heart tissue patch from human embryonic cell-derived heart muscle cells, blood vessel lining cells and fiber-producing cells, and successfully engraft the tissue into an animal.

Future studies will try to move heart cell regeneration closer toward clinical usefulness, according to Murry and his research team. They forecast that such research would include testing other sources of human cells and developing techniques to create bigger patches for treating larger animals through surgical transplantation or through catheter delivered injections.

Lastly, they concluded, researchers would need to test whether tissue patches actually improve physical functioning after implantation in damaged hearts.

In addition to Stevens and Murry, the other researchers on this study, entitled Physiological Function and Transplantation of Scaffold-Free and Vascularized Human Cardiac Muscle Tissue, were Kareen L. Kreutziger, senior fellow in pathology; Sarah K. Dupras, research scientist in pathology; F. Steven Korte, senior fellow in bioengineering: Michael Regnier, associate professor of bioengineering; Veronica Muskheli, research scientist in pathology; Marilyn B. Nourse, postdoctoral scientist, Geron Corp.; Kira Bendixen, research technologist; and Hans Reinecke, research assistant professor of pathology.

The research was supported by grants from the National Institutes of Health, a Bioengineering Cardiovascular Training Grant, and a Pathology of Cardiovascular Disease Training Grant.

Anti-swine flu drug Tamil flu now available across India

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Tamil flu
In an attempt to fight the menace of Swine Flu, an anti-swine flu drug Tamil flu is being launched by the Govt of India in the licenced shops across the country.

The launch of the drug came at a time when the deadly virus has claimed 257 lives and affected 8,153 people in the country.

The drug is sold under the trade name Tamiflu and is taken orally in capsules or a drink.

The ministry of health and family welfare issued a notification on Tuesday allowing “restricted sale” of tamiflu (Oselatamivir) the only available drugs that are used for the treatment of Swine Flu.

Taking into account the current spread of the Influenza A(H1N1) in the country, the health ministry decided that retail sale of tamiflu should be allowed in the country but in a regulated manner.

The retail sale of tamiflu was banned by the central government and its distribution was permissible only through public health institutions.

A 10-tablet strip of tamiflu costs Rs.280.

Nobel Prize In Chemistry: What Ribosomes Look Like And How They Functions At Atomic Level

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An X-ray structure of a bacterium ribosome.
The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry for 2009 jointly to Venkatraman Ramakrishnan, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom; Thomas A. Steitz, Yale University, New Haven, CT, USA; and Ada E. Yonath, Weizmann Institute of Science, Rehovot, Israel, "for studies of the structure and function of the ribosome".

The ribosome translates the DNA code into life

The Nobel Prize in Chemistry for 2009 awards studies of one of life's core processes: the ribosome's translation of DNA information into life. Ribosomes produce proteins, which in turn control the chemistry in all living organisms. As ribosomes are crucial to life, they are also a major target for new antibiotics.

This year's Nobel Prize in Chemistry awards Venkatraman Ramakrishnan, Thomas A. Steitz and Ada E. Yonath for having showed what the ribosome looks like and how it functions at the atomic level. All three have used a method called X-ray crystallography to map the position for each and every one of the hundreds of thousands of atoms that make up the ribosome.

Inside every cell in all organisms, there are DNA molecules. They contain the blueprints for how a human being, a plant or a bacterium, looks and functions. But the DNA molecule is passive. If there was nothing else, there would be no life.

The blueprints become transformed into living matter through the work of ribosomes. Based upon the information in DNA, ribosomes make proteins: oxygen-transporting haemoglobin, antibodies of the immune system, hormones such as insulin, the collagen of the skin, or enzymes that break down sugar. There are tens of thousands of proteins in the body and they all have different forms and functions. They build and control life at the chemical level.

An understanding of the ribosome's innermost workings is important for a scientific understanding of life. This knowledge can be put to a practical and immediate use; many of today's antibiotics cure various diseases by blocking the function of bacterial ribosomes. Without functional ribosomes, bacteria cannot survive. This is why ribosomes are such an important target for new antibiotics.

This year's three Laureates have all generated 3D models that show how different antibiotics bind to the ribosome. These models are now used by scientists in order to develop new antibiotics, directly assisting the saving of lives and decreasing humanity's suffering.

V Ramakrishnan wins Nobel prize for Chemistry

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Tamil Nadu-born Venkatraman Ramakrishnan, a senior scientist at the MRC Laborartory of Molecular Biology at Cambridge, has won the 2009 Nobel Prize for Chemistry along with two others, the Nobel Committee announced on Wednesday.

Born in 1952 in Chidambaram, Ramakrishnan shares the Nobel prize with Thomas E Steitz (US) and Ada E Yonath (Israel) for their "studies of the structure and function of the ribosome".


Ramakrishnan earned his B.Sc. in Physics (1971) from Baroda University and his Ph.D. in Physics (1976) from Ohio University.


He moved into biology at the University of California, San Diego, where he took a year of classes, then conducted research with Dr Mauricio Montal, a membrane biochemist.



With this 5.5 Angstrom-resolution structure, Ramakrishnan's group identified key portions of the RNA and, using previously determined structures, positioned seven of the subunit's proteins.


In the 21st September 2000 issue of Nature, Ramakrishnan published two papers. In the first of these, he presents the 3 Angstrom structure of the 30S ribosomal subunit.


His second paper reveals the structures of the 30S subunit in complex with three antibiotics that target different regions of the subunit. In this paper, Ramakrishnan discusses the structural basis for the action of each of these drugs.

After his postdoctoral fellowship, Ramakrishnan joined the staff of Brookhaven National Laboratory in the US. There, he began his collaboration with Stephen White to clone the genes for several ribosomal proteins and determine their three-dimensional structures.


He was also awarded a Guggenheim fellowship during his tenure there, and he used it to make the transition to X-ray crystallography.

Ramakrishnan moved to the University of Utah in 1995 to become a professor in the Department of Biochemistry. There, he initiated his studies on protein-RNA complexes and the entire 30S subunit.

He since moved to the MRC Laboratory of Molecular Biology in Cambridge, where he is a Senior Scientist and Group Leader in the Structural Studies Division. He joins the list of several Nobel laureates who worked at the laboratory.

Women's Soccer: Get Fit While Having Fun

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New research shows that women benefit more from playing recreational soccer than from running when it comes to overall fitness. And that's not all: women playing soccer experience a higher degree of motivation when it comes to sticking to their sport, and they increase their ability to bridge and create new acquaintances. Video and photos available from the project website.The study

Over a period of two years, 30 scientist lead by Associate Professor Peter Krustrup, University of Copenhagen, have investigated physiological, sociological and psychological aspects of women's soccer in comparison to running. 100 untrained adult premenopausal women have participated in the study.

The women (65 participated in the physiological study) were randomly divided into three groups: One soccer group, one running group and one control group. The soccer players and runners trained twice a week for one hour. After four and sixteen weeks, all the subjects went through extensive physiological tests. The same 65 subjects + another 35 women playing in soccer clubs were continually observed and interviewed to study the sociological and psychological effects of their training.

Soccer players stick to their game

Many women find it difficult to fit in sport and exercise in their busy daily lives, and many state family and especially small children as the main reason for not finding the time.

The study reveals that contrary to common assumption, the flexibility of running as exercise form actually makes running harder to stick to for most women than soccer, which requires a fixed time and place.

"What is really interesting is that the soccer players differed from the runners in their motivation. The runners were motivated by the idea of getting in shape and improving health. But the soccer players focused on the game itself and were motivated by the social interaction and by having fun with others. As it turns out, the soccer players got in better shape than the runners, and that combined with the social benefits makes soccer a great alternative to running", says Associate Professor Laila Ottesen and continues:

"The women who played soccer have continued their soccer training as a group whereas few of the women in the running group continued running after the study. Actually, some of the women from the running group joined teams with the soccer group after the project finished."

Why soccer players are more fit

When choosing a sport, women tend to favour cardiovascular training to strength training although the build-up of muscles and bone strength are vital to preserve health into old age.

"While playing soccer, the women have high heart rates and perform many sprints, turns, kicks and tackles, making soccer an effective integration of both cardio and strength training", says project leader Peter Krustrup.

"Our study shows that the 16 weeks of recreational women's soccer causes marked improvement in maximal oxygen uptake, muscle mass and physical performance, including the endurance, intermittent exercise and sprinting ability, explains Peter Krustrup, and continues

"This makes soccer a very favourable choice of exercise training for women.

In the recent decade, we have seen a significant rise in women and girls playing soccer. It seems as though women are really beginning to take in soccer and make it a popular sport for women on their own terms. This is a very positive step forward, not only because of the improved physical fitness and health profile but also for the enjoyment of sports", Krustrup concludes.

Publication plans

The present results will be submitted online in the international journal Scandinavian Journal of Medicine and Science in Sports next week (Bangsbo, Nielsen, Mohr, Randers, Krustrup, Brito, Nybo and Krustrup. Performance enhancements and muscular adaptations of a 16-week recreational football intervention for untrained women. Scand J Med Sci Sports, 2009).

In January 2010, the same journal will publish a supplementum describing multiple health effects of recreational football for various subject groups, including men, women, young and elderly. The supplementum includes one review and 13 original scientific papers.

The data will also be presented at the Scandinavian Congress of Medicine and Science in Sports 2010, Copenhagen, Denmark, 4-6 February 2010, and at the 3rd International Football Medicine Conference in Sun City, South Africa, 19-21 February 2010.

The project group currently includes collaborators from Switzerland, Norway and Italy, and major applications are currently being processed to include collaborators from England, Portugal, Belgium, Australia and Kenya.

Funding

The work has been financially supported by F-MARC, The Danish Ministry of Culture, The Danish Football Association and The Danish Sport Federation, The Danish Gymnastics and Sports Associations and by 3F (United Federation of Danish Workers).

Phthalates Hard To Avoid In Food

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Phthalates – the softening agents in synthetic materials – were a hot topic during the last decade and have been linked to deformities in the male genitals, diabetes, premature births and excess weight. Now, a study from ETH Zurich has revealed that they are extremely difficult to avoid, even if you eat healthily.Synthetic materials are omnipresent in our everyday lives. To make them soft, flexible, durable and nicer, PVC or synthetically produced rubber is mixed with an organic compound made up of phthalate ester and alcohol (otherwise known as phthalates), for example. The synthetics industry uses about five million tons of these softeners annually; they are present in conventional flooring, cables and packaging materials, but also medical products and cosmetics.

Easy pickings

Because they are everywhere, they can easily enter the food chain and the human organism via food and drink. When and where this happens, however, is difficult to ascertain and has barely been researched. “After all,” says Michael Siegrist, a professor at the Institute of Environmental Decisions at ETH Zurich, “often you don’t know where in the food chain the phthalates get into the food – whether they come from the bucket used to harvest olives, the conveyor belt, or elsewhere in the production chain”.

Consequently, Siegrist supervised a study at the Institute of Environmental Decisions in conjunction with the Institute of Chemistry and Bioengineering at ETH Zurich which showed that sensible eating cannot really prevent the intake of phthalates. As a matter of fact, consumers who eat naturally and healthily and try to keep the chemical additives in their food to a minimum might even be ingesting more phthalates on a daily basis than those who do not worry about their diet at all.

On the one hand, the study was aimed at assessing consumers’ eating habits to show the extent to which they are exposed to phthalates. On the other hand, however, the scientists examined the relationship between the consumers’ exposure and their interest in a natural and healthy diet, as well as their risk perception of chemicals in food, such as pesticides or phthalates, such as with pesticides or phthalates. For the first time, the scientists thus established a link between consumer perception and physical reality as regards the intake of food containing phthalates.

In their study, the research team polled about 1200 people in German-speaking Switzerland about their eating habits. The respondents were asked to provide information on their diet. The evaluation of the survey yielded four characteristic groups: people who eat health-consciously and also rely on vitamin supplements compared to those who eat healthily and naturally, people who do not worry about their food and react passively, and people who consume an especially high amount of fatty and sugary food and ready-to-eat meals.

Junk food no worse than healthy products

To quantify the phthalate amounts ingested by the test people in their food, the researchers used existing data for food where the phthalate exposure had already been examined. It became clear that the people who have a healthy and natural diet ingest most of some phthalates, whereas those who behave more passively in their eating habits are the least exposed to the pollutants. All in all, the results of the two nutritionally aware groups and the “fatty, sugary and ready-to-eat meals” group were similar. However, it seems reassuring that the various tolerance levels issued by the European Food Safety Agency for different softening agents did not even come close to being reached in the study, let alone exceeded. Nevertheless, the researchers admit that the result should be taken with a pinch of salt as not all foods could be taken into account.

All the same, the result seems ironic and the researchers are also at a loss to explain why. Maria Dickson-Spillmann, Siegrist’s doctoral student and first author of the study, stresses that the matter still needs a lot of research. She says, “Our results show that even consumers who make a point of having a healthy and natural diet cannot escape chemical pollutants like phthalates. The findings underline the importance of food controls by cantonal laboratories”. Nonetheless, it would be wrong to advise consumers against fresh fruit and vegetables, for example, as this may cause other health risks.

In recent years, various studies have suggested that phthalates act like hormones in humans: above all, deformities in the genital area in male offspring became apparent. However, additional but still debatable links to sterility and diabetes in men, premature births in pregnant women and premature breast development in girls were also established. Consequently, teething rings for babies without phthalates are now being promoted, for instance, and the food industry is using rubber gloves and packaging materials that hardly emit any phthalates, or do not contain any at all. That said, due to their omnipresence, it is highly unlikely that they can be eliminated from the food chain altogether.

Breast Milk Should Be Drunk At The Same Time Of Day That It Is Expressed

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The levels of the components in breast milk change every 24 hours in response to the needs of the baby. A new study published in the journal Nutritional Neuroscience shows, for example, how this milk could help newborn babies to sleep.
Breast milk contains various ingredients, such as nucleotides, which perform a very important role in regulating babies' sleep. The new study confirms that the composition of breast milk changes quite markedly throughout the day.

The scientists looked for three nucleotides in breast milk (adenosine, guanosine and uridine), which excite or relax the central nervous system, promoting restfulness and sleep, and observed how these varied throughout a 24-hour period.

The milk, collected from 30 women living in Extremadura, was expressed over a 24-hour period, with six to eight daily samples. The highest nucleotide concentrations were found in the night-time samples (8pm to 8am).

"This made us realise that milk induces sleep in babies", Cristina L. Sánchez, lead author of the article and a researcher at the Chrononutrition Laboratory at the University of Extremadura, tells SINC.

"You wouldn't give anyone a coffee at night, and the same is true of milk – it has day-specific ingredients that stimulate activity in the infant, and other night-time components that help the baby to rest", explains Sánchez.

In order to ensure correct nutrition, the baby should be given milk at the same time of day that it was expressed from the mother's breast. "It is a mistake for the mother to express the milk at a certain time and then store it and feed it to the baby at a different time", points out the researcher. .

The benefits of breast milk

The World Health Organisation (WHO) says breast milk is the best food for the newborn, and should not be substituted, since it meets all the child's physiological requirements during the first six months of life. It not only protects the baby against many illnesses such as colds, diarrhoea and sudden infant death syndrome, but can also help prevent future diseases such as asthma, allergies and obesity, and promotes intellectual development.

The benefits of breastfeeding also extend to the mother. Women who breastfeed lose the weight gained during pregnancy more quickly, and it also helps prevent against anaemia, high blood pressure and postnatal depression. Osteoporosis and breast cancer are also less common among women who breastfeed their children.