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20 September 2010

Teens who smoke, weigh too much, fail to exercise may risk headache

THIS STUDY analyzed data on 5,847 teenagers, including how often they exercised, how much they weighed and whether they smoked. Among those who were overweight, smoked and did not exercise, about 55 percent had recurring headaches, compared with 25 percent of the teens who had none of these traits. Smoking alone raised the risk for headaches by 50 percent, being overweight increased it by 40 percent and not exercising raised it by 20 percent, when compared with teens who did not smoke, were not overweight and did exercise. Frequent headaches were nearly twice as common among teens with two negative behaviors and more than three times as frequent with three such behaviors.

WHO MAY BE AFFECTED? Teenagers. Physical activity often decreases as kids become teens. In the United States, an estimated 20 percent of high school students and 6 percent of middle school students smoke, and at least 20 percent are overweight or obese, according to the Centers for Disease Control and Prevention.

CAVEATS Data on the teens' behaviors came from their responses to questionnaires as well as from interviews and examinations. Other factors, such as socioeconomic and psychological status, were not considered and may have affected the results. The study did not test whether changing negative behaviors would reduce the frequency of headaches.

Antibiotics mess up your stomach, U.S. study finds

An intimate study of three women given ciprofloxacin showed the drug suppressed entire populations of beneficial bacteria, and at least one woman took months to recover.

The study, published in the Proceedings of the National Academy of Sciences, supports the common wisdom that antibiotics can damage the "good" germs living in the body.

It may also support the idea behind the development of so-called probiotic products including yogurt with live cultures of bacteria.

The researchers tested the three volunteers daily, giving them a five-day course of the commonly used antibiotic ciprofloxacin twice during the 10-month study.

They ran DNA tests on stool samples from the volunteers to determine what kind of microbes were living in the gut.

"The effect of ciprofloxacin on the gut microbiota was profound and rapid," Les Dethlefsen and David Relman of Stanford University in California wrote.

"By one week after the end of each course, communities began to return to their initial state, but the return was often incomplete."

More and more studies support the idea that humans and other animals have a symbiotic relationship with germs. Microbes in the intestines help digest food and "good" germs can take up space and keep bad germs away.

"The human distal gut is one of the most complex ecosystems on the planet," the researchers wrote in the study, available here

Gut microbes can affect obesity and may play a role in allergy. Lactobacillus reuteri, found in breast milk, may protect against rotavirus infections, other researchers have found.

Several recent studies have found that certain bacteria cause inflammation that can affect appetite as well as inflammatory bowel conditions like Crohn's disease and colitis.

Regularly wiping out the body's bacterial population could also be helping drive the rapid spread of drug-resistant superbugs, the Stanford team said.

"One potential ramification of the altered community is an enhanced carriage of antibiotic-resistance genes in the human population," they wrote.

"Every course of antibiotics may represent another roll of the dice," they added -- potentially a "bad" strain to replace a beneficial species.

Chemicals In Indoor Swimming Pools May Increase Cancer Risk

Newswise — Swimming in indoor chlorinated pools may induce genotoxicity (DNA damage that may lead to cancer) as well as respiratory effects, but the positive health effects of swimming can be maintained by reducing pool levels of the chemicals behind these potential health risks, according to a new study published in a set of three articles online September 12 ahead of print in the peer-reviewed journal Environmental Health Perspectives (EHP). This study is the first to provide a comprehensive characterization of disinfection by-products (DBPs) in an indoor pool environment and the first to study the genotoxicity of exposure to these chemicals among swimmers in an indoor chlorinated pool.

DBPs form in pool water from reactions between disinfectants such as chlorine and organic matter that is either present naturally or is introduced by swimmers, such as sweat, skin cells, and urine. Previous epidemiologic studies have found an association between exposure to DBPs in drinking water and risk of bladder cancer, and one such study has found this association for dermal/inhalational exposure such as occurs during showering, bathing, or swimming.

The new study details a comprehensive investigation of DBPs and mutagenicity of water samples collected from two indoor pools, one disinfected with chlorine, the other with bromine. In addition, short-term changes in biomarkers of genotoxicity and respiratory effects were studied in swimmers who swam in the chlorinated pool. No previous studies have combined investigations of the mutagenicity (ability to cause permanent DNA mutations) of pool water with a comprehensive chemical characterization of the water and studies of human exposures, the authors stated.

Evidence of genotoxic effects were seen in 49 healthy adults after they swam for 40 minutes in the chlorinated pool. Specifically, researchers found increases in two genotoxicity biomarkers relative to the concentration of the most common types of DBPs in exhaled breath, which were used as a measure of the swimmers’ exposures. The biomarkers that increased were micronuclei in blood lymphocytes, which have been associated with cancer risk in healthy subjects, and urine mutagenicity, which is a biomarker of exposure to genotoxic agents.

Detailed measurements were also made of the most common exhaled DBPs (trihalomethanes) in air around the pool and in exhaled breath of the swimmers before and after swimming. Researchers measured several biomarkers of respiratory effects after swimming and found changes in only one—a slight increase in serum CC16, which suggests an increase in lung epithelium permeability. This result was explained by the effects of exercise itself as well as exposure to DBPs. Further research is needed to sort out the clinical relevance of this acute change, the researchers stated.

In addition, the authors identified more than 100 DBPs in the pool waters, some never reported previously in swimming pool water and/or chlorinated drinking water. In vitro assays showed that the swimming pool water was mutagenic at levels similar to that of drinking water but was more cytotoxic (can kill cells at a lower concentration) than drinking water.

The human exposures studied were short-term, and further investigations of genotoxic and respiratory effects of longer-term exposures are needed, the authors stated. Also noted was a need for further research on an array of swimming pools under various conditions of maintenance and use, as well as more complete evaluations of the uptake and potential effects of the wide range of compounds present in pool water. These are preliminary results that should be confirmed in studies with larger sample sizes.

16 September 2010

Coffee may protect against DNA damage: Study

A daily cup of coffee may reduce the oxidative damage to DNA by 12 percent, according to a pan-European study.

Researchers from the University of Vienna, Nestlé, and the University of Belgrade report that paper-filtered coffee – the most widely consumed form in Central Europe and the US – may protect against oxidative DNA-damage.

No changes in overall antioxidants status of the 38 participants were observed, according to findings published in Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis.

“It is conceivable that indirect effects such as reduced uptake of glucose via the gastrointestinal tract, which was seen with specific types of coffee and with chlorogenic acids may play a role as it is known that alterations of the energy metabolism may lead to reduced reactive oxygen species formation in the mitochondria,” wrote the researchers.

The study was funded by the Institute of Scientific Information on Coffee (ISIC) – a scientific consortium of European coffee companies.

Health benefits

A recent review by Mario Ferruzzi from Purdue University noted that coffee is one of the richest sources of polyphenols in the Western diet, with one cup of the stuff providing 350 milligrams of phenolics. Of these, the most abundant compounds coffee are chlorogenic acids, making up to 12 per cent of the green coffee bean. The most abundant of these compounds is caffeic acid (Physiology & Behavior, 2010, Vol. 100, pp. 33-41).

“A better understanding of how the beverage composition impacts phenolic profiles and their bioavailability is critical to development of beverage products designed to deliver specific health benefits,” he added.

The beverage, and its constituent ingredients, has come under increasing study with research linking it to reduced risk of diabetes, and improved liver health.

Coffee, one of the world's largest traded commodities produced in more than 60 countries and generating more than $70bn in retail sales a year, continues to spawn research and interest, and has been linked to reduced risks of certain diseases, especially of the liver and diabetes.
Study details


The researchers recruited 38 people to participate in their controlled intervention trial with a cross-over design. The subjects were assigned to drink either 800 ml coffee or water daily for five days. Various measures of DNA damage were used.


At the end of the study, a reduction in DNA damage, as measured by a reduction in the formation of oxidised purines of 12.3 percent was observed in the coffee drinkers.


On the other hand, no significant changes in levels of antioxidants in the blood, or levels of reactive oxygen species in the blood were observed,


“Overall, the results indicate that coffee consumption prevents endogenous formation of oxidative DNA-damage in human, this observation may be causally related to beneficial health effects of coffee seen in earlier studies,” concluded the researchers.


From bean to leaf


Only last week, we reported on findings from a human study that indicated that green tea may also reduce DNA damage. Researchers from The Hong Kong Polytechnic University reported in the British Journal of Nutrition that combined results from a human supplementation trial and an in vitro study indicated a 20 percent reduction in levels of DNA damage.


“The results indicate that green tea has significant genoprotective effects and provide evidence for green tea as a ‘functional food’,” wrote the Hong Kong-based researchers.

Study details


The researchers recruited 38 people to participate in their controlled intervention trial with a cross-over design. The subjects were assigned to drink either 800 ml coffee or water daily for five days. Various measures of DNA damage were used.


At the end of the study, a reduction in DNA damage, as measured by a reduction in the formation of oxidised purines of 12.3 percent was observed in the coffee drinkers.


On the other hand, no significant changes in levels of antioxidants in the blood, or levels of reactive oxygen species in the blood were observed,


“Overall, the results indicate that coffee consumption prevents endogenous formation of oxidative DNA-damage in human, this observation may be causally related to beneficial health effects of coffee seen in earlier studies,” concluded the researchers.


From bean to leaf


Only last week, we reported on findings from a human study that indicated that green tea may also reduce DNA damage. Researchers from The Hong Kong Polytechnic University reported in the British Journal of Nutrition that combined results from a human supplementation trial and an in vitro study indicated a 20 percent reduction in levels of DNA damage.


“The results indicate that green tea has significant genoprotective effects and provide evidence for green tea as a ‘functional food’,” wrote the Hong Kong-based researchers.

Study details


The researchers recruited 38 people to participate in their controlled intervention trial with a cross-over design. The subjects were assigned to drink either 800 ml coffee or water daily for five days. Various measures of DNA damage were used.


At the end of the study, a reduction in DNA damage, as measured by a reduction in the formation of oxidised purines of 12.3 percent was observed in the coffee drinkers.


On the other hand, no significant changes in levels of antioxidants in the blood, or levels of reactive oxygen species in the blood were observed,


“Overall, the results indicate that coffee consumption prevents endogenous formation of oxidative DNA-damage in human, this observation may be causally related to beneficial health effects of coffee seen in earlier studies,” concluded the researchers.


From bean to leaf


Only last week, we reported on findings from a human study that indicated that green tea may also reduce DNA damage. Researchers from The Hong Kong Polytechnic University reported in the British Journal of Nutrition that combined results from a human supplementation trial and an in vitro study indicated a 20 percent reduction in levels of DNA damage.


“The results indicate that green tea has significant genoprotective effects and provide evidence for green tea as a ‘functional food’,” wrote the Hong Kong-based researchers.

Omega-3, vitamins C and E may boost pancreatic health

Increased intakes of omega-3 fatty acids, and vitamins C and E may reduce the risk of pancreatic cancer by over 30 percent, suggests new research.

Data from residents in the San Francisco Bay Area found that consuming at least 850 milligrams of omega-3 fatty acids per day was associated with a 53 percent reduction in the risk of pancreatic cancer, compared to intakes of between 330 and 580 milligrams per day.

According to findings published in the International Journal of Cancer, benefits were also observed for intakes of vitamin C and E, the highest average intakes associated with 31 and 33 percent reductions, respectively, compared with the lowest average intakes.

On the flip side, researchers from the University of California San Francisco report that high intakes of saturated fats and certain monounsaturated fatty acids may increase the risk of pancreatic cancer – the fourth most common cause of cancer mortality in the US and the cause of 33,400 deaths among men and women in 2007.

“Results from this large population-based case-control study provide additional evidence that dietary factors and use of supplements may affect risk of pancreatic cancer,” wrote the researchers, led by Paige Bracci from the Department of Epidemiology and Biostatistics.

“Our results showing increased risk of pancreatic cancer with increased saturated fatty acid intake and decreased risk with high intake of long-chain omega-3 fatty acid and of vitamin C and E from supplements contribute new data to the epidemiologic literature on pancreatic cancer,” they added.

Citrus compounds may reduce cancer risk: Study

Daily consumption of citrus may reduce the risk of a range of cancers, especially pancreatic and prostate cancer, suggests a new study from Japan.

Eating citrus daily was associated with a 11 and 14 percent reduction in the incidence of all types of cancer for men and women, respectively, according to a study with 42,270 people living in North Eastern Japan.

Findings published in the International Journal of Cancer also indicate that co-consumption with one cup of green tea a day produced an enhanced protective effect.

“Because of the popularity of citrus and green tea among the Japanese people, these findings suggest that a possible joint effect between them may have implications for public health,” wrote the researchers, led by Wen-Qing Li from Tohoku University Graduate School of Medicine.

“However, we have no information on the difference between a second cup made from the same or another set of leaves, the same as most epidemiological surveys in Japan. In any event, the mechanism responsible for this joint effect needs to be clarified further.”

Global crisis

“Cancer represents a crisis for public health, with a global estimated 12.4 million incident cases and 7.6 million deaths from cancer overall in 2008,” state the Japanese researchers. Some “basic studies” have indicated the potential for citrus to reduce the risk of cancer, linked to the compounds in the fruit exhibiting antioxidant potential.

Despite such links, actual studies of citrus intakes and the incidence of cancer are not abundant.

Study details

The Japanese scientists analysed data from 42,470 people in the Ohsaki National Health Insurance Cohort and correlated the effect of citrus and green tea consumption on the overall incidence of cancer. The average age of participants was 59.

After nine years of follow-up, the researchers documented 3,398 cases of cancer. Citrus consumption was divided into five groups: ‘never’; ‘occasionally’; ‘1 to 2 times per week’; ‘3 to 4 times per week’; and ‘daily’.

The results showed that daily consumption was correlated with significant reductions in the risk of all cancer, and especially for prostate and pancreatic cancer. In these cases, the risk reduction was calculated to be 37 and 38 percent, respectively, for daily citrus intakes.

Furthermore, people who drank one cup of green tea a day the reduction in the risk of overall cancer was 17 percent, said the researchers.

“These findings suggest that citrus consumption is associated with reduced all-cancer incidence, especially for subjects having simultaneously high green tea consumption,” wrote the scientists. “Further work on the specific citrus constituents is warranted, and clinical trials are ultimately necessary to confirm the protective effect.”

9 September 2010

Cranberry Juice Shows Promise Blocking Staph Infections

ScienceDaily (Sep. 3, 2010) — Expanding their scope of study on the mechanisms of bacterial infection, researchers at Worcester Polytechnic Institute (WPI) have reported the surprise finding from a small clinical study that cranberry juice cocktail blocked a strain of Staphylococcus aureus (S. aureus) from beginning the process of infection.

The data was reported in a poster presentation at the American Chemical Society's national meeting in Boston on August 23, 2010, by Terri Camesano, professor of chemical engineering at WPI. "Most of our work with cranberry juice has been with E. coli and urinary tract infections, but we included Staphylococcus aureus in this study because it is a very serious health threat," Camesano said. "This is early data, but the results are surprising."

The virulent form of E. coli that Camesano studies is the primary cause of most urinary tract infections. Strains of S. aureus can cause a range of "staph infections" from minor skin rashes to serious bloodstream infections. One particular strain, known as Methicillin-resistant Staphylococcus aureus, or MRSA, is a growing public health problem in hospitals, nursing homes, and other institutions because it doesn't respond to most antibiotics.

To cause an infection, bacteria must first adhere to a host, then gather together in colonies to form a biofilm. In the current study, Camesano recruited healthy female students at WPI to drink either cranberry juice cocktail or a placebo fluid that looked and tasted like cranberry juice. The subjects provides urine samples at prescribed intervals after drinking the juice or placebo, and those samples were incubated in petri dishes with several strains of E. coli and a single strain of S. aureus. Camesano's team stained the bacteria with a special dye, then used a spectrophotometer to measure the density of the bacterial colonies in the dishes over time. Their analysis showed that the urine samples from subjects who had recently consumed cranberry juice cocktail significantly reduced the ability of E. coli and S. aureus to form biofilms on the surface of the dishes.

"What was surprising is that Staphylococcus aureus showed the most significant results in this study," Camesano said. "We saw essentially no biofilm in the staph samples, which is very surprising because Staph aureus is usually very good at forming biofilms. That's what makes it such a health problem."

With E. coli, Camesano's focal point is the small hair-like projections known as fimbriae, which act like hooks and help the bacteria latch onto cells that line the urinary tract. Camesano has shown that exposure to cranberry juice causes the fimbriae on E. coli to curl up, blunting their ability to attach to cells. S. aureous, however, doesn't have fimbirae, so there must be other reasons why the cranberry juice affected its biofilm formation in the study. "These results do create more questions than answers," Camesano said. "We believe this is an important new area to explore, and we are now thinking about how best to proceed."

Since bacterial adhesion is required for infection, Camesano hopes that better understanding of the specific mechanisms and forces involved in biofilm formation will help inform future studies aimed at identifying potential drug targets for new antibiotics. The data may also be useful in studies aimed at engineering the surfaces of invasive medical devices like catheters to make them more resistant to bacterial adhesion.

The research detailed in the current study was supported by grants from the Cranberry Institute and the Wisconsin Cranberry Board.

3 September 2010

Broccoli 'boosts' healthy gut

Extracts of broccoli and banana may help in fighting stomach problems, research suggests.

Laboratory studies show fibres from the vegetables may boost the body's natural defences against stomach infections.

Trials are under way to see if they could be used as a medical food for patients with Crohn's disease.

Crohn's disease is an inflammatory bowel disease that causes symptoms such as diarrhoea and abdominal pain.

Scientists at the University of Liverpool looked at how roughage from vegetables influenced the passage of harmful bacteria through cells inside the gut.

They found that fibres from the plantain, a type of large banana, and broccoli, were particularly beneficial. But a common stabiliser added to processed foods during the manufacturing process had the opposite effect.

Dr Barry Campbell, from the University of Liverpool, said: "This research shows that different dietary components can have powerful effects on the movement of bacteria through the bowel.

"We have known for some time the general health benefits of eating plantain and broccoli, which are both high in vitamins and minerals, but until now we have not understood how they can boost the body's natural defences against infection common in Crohn's patients.

"Our work suggests that it might be important for patients with this condition to eat healthily and limit their intake of processed foods."

M-cells

The research, published in the journal Gut, and carried out in collaboration with experts in Sweden and Scotland, investigated special cells, called M-cells, which line the gut and ward off invading bacteria.

Work was carried out in laboratory-grown cells and tissue samples from patients undergoing surgery for stomach problems.

Clinical trials are now underway in 76 Crohn's patients to find out whether a medical food containing plantain fibres could help keep the disease at bay.

"It may be that it makes sense for sufferers of Crohn's to take supplements of these fibres to help prevent relapse," said Professor Jon Rhodes of the University of Liverpool.

Commenting on the study, a spokesperson for Crohn's and Colitis, which represents patients with inflammatory bowel disorders, welcomed further insight into how the gut combats bacteria like E.Coli.

"Knowledge of the M-cell role offers a more detailed explanation as to why a healthy diet can improve the health and well being for people with Crohn's disease and healthy individuals alike," she said.

31 August 2010

Andy Roddick Rolls, Holds Court on Heat, Blake, Scoliosis

Andy RoddickNEW YORK -- Andy Roddick enjoyed a relatively easy first-round match on Monday at the U.S. Open, defeating Stephane Robert of France 6-3, 6-2, 6-2. Roddick, the No. 9 seed, lost his serve only once and broke Robert in half of his 12 service games. Completing the match in one hour and 42 minutes was important for Roddick, who recently suffered through a battle of mononucleosis.

On his health, Roddick said, "It's going the right way. To be honest, once you decide to play, I think you throw all the excuses and everything else out the window. If I decide to play, then it's up to me to give 100 percent of what I have. So it's not something I really want to discuss too much from this point forward. I'm not going to analyze it every day."

Like most Roddick press conferences, his meeting with the media after his victory over Robert covered subjects beyond his own tennis game.

Roddick, a longtime Miami Heat fan, was asked about his team's acquisition of free agents LeBron James and Chris Bosh.

"I'm sick of defending my fanhood," said Roddick. "I was going to the games in '01, when they were paying people to come. I was in Boca (Raton) for a long time and went to four or five home games a year. I'm excited.

"I was just hoping and praying they'd re-sign Dwayne (Wade). Then when Bosh came, I was ecstatic. Then when LeBron came it was bordering on ridiculous. Like everyone else, I'm excited to see how it all goes together."

Roddick's passion for Miami's basketball team, however, is dwarfed by his admiration for Davis Cup teammate James Blake, who was honored during Monday night's opening ceremonies for overcoming scoliosis to become a top player.

"I'm extremely biased," said Roddick. "I'm a massive James Blake fan. His career is one thing, but I also like his character. I like the way he goes about his business. He's been a real good friend to me."

Blake, a wild-card entry in this year's Open, has struggled of late, but is hopeful for another memorable run.

Said Roddick: "My biggest hope for James is that he can get healthy enough to have a run that he would like."

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