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Friday, May 13, 2011

Eat Less, Live Longer?

HealthDay News

Friday, May 13, 2011

FRIDAY, May 13 (HealthDay News) -- People who cut their daily caloric intake by 25 percent or more may live longer than those who do not, a new study suggests.

Researchers from the Washington University School of Medicine in St. Louis found that significantly limiting calories lowers core body temperature (the temperature at which all of the functions in the body can operate with maximum efficiency), which has been shown to prolong life.

The study, published recently in the journal Aging, compared the core body temperatures of 24 people in their mid-50s who practiced calorie restriction for at least six years to 24 of their peers who ate a standard Western diet with higher calorie and fat intake. The core body temperatures of 24 endurance runners in the same age group were also measured to determine if simply being lean was enough to lower body temperature without calorie restriction.

"The people doing calorie restriction had a lower average core body temperature by about 0.2 degrees Celsius, which sounds like a modest reduction but is statistically significant and similar to the reduction we have observed in long-lived, calorie-restricted mice," principal investigator Dr. Luigi Fontana said in a news release from Washington University. "What is interesting about that is endurance athletes, who are the same age and are equally lean, don't have similar reductions in body temperature."

Although restricting calories can double or even triple the lifespan of simple organisms, the researchers admitted it is not yet clear how much longer calorie restriction might help humans live. The study authors noted that those who practice the strict diet hope to survive past 100 years.

The researchers also pointed out that simply lowering body temperature isn't enough to increase lifespan. Fontana noted that how lower core body temperatures are achieved is important. "I don't think it ever will be possible to be overweight and smoking and drinking and then take a pill, or several pills, to lower body temperature and lengthen lifespan," he said.

"What may be possible, however, is to do mild calorie restriction, to eat a very good diet, get mild exercise and then take a drug of some kind that could provide benefits similar to those seen in severe calorie restriction," Fontana added.

More information

The U.S. National Institute on Aging has more information on calorie restriction and longevity.

Digestive Problems Early in Life May Increase Risk for Depression, Study Suggests

ScienceDaily

Friday, May 13, 2011

ScienceDaily (May 13, 2011) — Depression and anxiety may result from short-term digestive irritation early in life, according to a study of laboratory rats by researchers at the Stanford University School of Medicine. The findings suggest that some human psychological conditions may be the result, rather than the cause, of gastrointestinal disorders such as irritable bowel syndrome.

"A lot of research has focused on understanding how the mind can influence the body," said Pankaj Pasricha, MD, professor and chief of gastroenterology and hepatology. "But this study suggests that it can be the other way around. Gastric irritation during the first few days of life may reset the brain into a permanently depressed state."

Clearly not all stomach upsets lead to lifelong psychological problems, however. The impact of the irritation may depend on when it occurs during development or the genetic makeup of the affected person, the researchers believe. In particular, the viscera, or internal organs, are particularly vulnerable early in development.

Pasricha is the senior author of the study, published in PLoS ONE. Research associate Liansheng Liu is the lead author of the research. The Stanford scientists collaborated with researchers from the University of California-San Francisco and the University of Kansas on the study.

About 15 to 20 percent of people experience what physicians call functional dyspepsia, or persistent or recurring pain in the upper abdomen. Researchers like Pasricha have long noted that these people are also more likely than their peers to be anxious or depressed. Conventional wisdom has held that stress hormones associated with a patient's altered mood were responsible for his or her digestive disturbances.

However, there is another option. "The gut and the brain are hardwired together by the vagus nerve, which runs from the brain to the body's internal organs" said Pasricha. "In addition, the gut has its own nervous system that is relatively independent. So the communication between the gut and the adult brain is elaborate and bi-directional, and changes in the gut are signaled directly to the brain."

Because many of these patients date their gastrointestinal problems back to early childhood, before their psychological symptoms began, Pasricha and his colleagues wondered if the digestive disturbances could instead be causing the mood disorders. The possibility was bolstered by the fact that recent research by other groups has linked depression and anxiety in humans to changes in the composition of gut bacterial populations.

To test their hypothesis, the researchers used a laboratory model of functional dyspepsia they had developed years earlier. They subjected 10-day-old laboratory rats to mild stomach irritation daily for six days. They had previously shown that during the vulnerable newborn period such treatment, which causes a temporary inflammation or injury, results in hypersensitivity and functional abnormalities that persist long after the initial damage has been repaired.

"We hypothesized that this treatment might also be affecting the development of central nervous system, and driving the animals to anxiety and depression," said Pasricha.

Indeed, as the researchers assessed the behavior of the treated rats when the animals were 8 to 10 weeks old, they found that those rats with early gastric irritation were significantly more likely than their peers to display depressed and anxious behaviors including a decreased consumption of sugar water, less-active swimming in a pool of warm water and a preference for dark rather than light areas in a maze.

The treated rats also exhibited increased levels of the stress hormones corticosterone and corticotrophin after an injection of saline, and had higher-than-normal resting levels of corticosterone and corticotrophin-releasing factor, or CRF. Blocking the animals' ability to perceive sensation from their gut with a drug did not affect their behavior, indicating that the rats were not responding to ongoing pain. In contrast, inhibiting the activity of CRF, which is known to be associated with depression in humans and animals, caused the treated rats to behave more normally in the tests.

"It seems that when the rats are exposed to gastric irritation at the appropriate point in time," said Pasricha, "there is signaling across the gut to the brain that permanently alters its function."

The researchers are now planning to investigate exactly how that signaling is initiated and acts in the brain, and whether it might be possible to develop new ways to treat depression and anxiety in humans.

"We'd like to know whether the vagus nerve is involved, and confirm what changes may occur in the brain in response to this signal," said Pasricha. "The vast majority of humans don't experience any long-lasting consequences from transient infections. But there may be subset of patients who are genetically predisposed to this effect by mechanisms we don't yet understand yet. Our hope is that this work will open another avenue for exploring, understanding and treating these very complex syndromes."

In particular, electrical stimulation of the vagus nerve has recently been approved by the Food and Drug Administration for treatment-resistant depression; this research may help researchers better understand and optimize this new approach.

In addition to Pasricha and Liu, other Stanford researchers involved in the work include Robert Sapolsky, PhD, the John A. and Cynthia Fry Gunn Professor, and Kshama Mehta, PhD, an instructor in gastroenterology and hepatology. The research was funded by Stanford's Department of Medicine.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Liansheng Liu, Qian Li, Robert Sapolsky, Min Liao, Kshama Mehta, Aditi Bhargava, Pankaj J. Pasricha. Transient Gastric Irritation in the Neonatal Rats Leads to Changes in Hypothalamic CRF Expression, Depression- and Anxiety-Like Behavior as Adults. PLoS ONE, 2011; 6 (5): e19498 DOI: 10.1371/journal.pone.0019498

More signs diabetes drug linked to bladder cancer

By Alison McCook Alison Mccook

Reuters Health

Friday, May 13, 2011

NEW YORK (Reuters Health) – A review of official reports of bad drug reactions is revealing more signs that people taking the diabetes drug Actos are at higher risk of developing bladder cancer.

Between 2004 and 2009, more than half a million adverse reactions among people taking anti-diabetic drugs were added to an official U.S. Food and Drug Administration database. Among those reports were 138 instances of bladder cancer in patients taking at least one of more than 15 different anti-diabetic drugs.

However, more than a fifth of those bladder cancers were in patients taking Actos (pioglitazone), suggesting a "disproportionate risk" in comparison with other anti-diabetics, said study author Dr. Elisabetta Poluzzi of the University of Bologna in Italy.

A certain number of people taking a drug will always develop other problems, she explained, and it's often not clear whether those problems stem from the drug itself. As a result, these findings do not show Actos increases the risk of bladder cancer, she cautioned - just that researchers should look into it further.

"Disproportion is indicative of possible risk," Poluzzi told Reuters Health in an email, "not of an actual risk."

Still, this is not the first report to tie the drug to bladder cancer, and the possibility of increased cancer risk is already included in the prescribing information for the drug.

Last year, the FDA began a safety review of Actos after receiving early results from a long-term study by the drug's maker, Takeda Pharmaceutical Co Ltd. That study showed a raised risk of bladder cancer in patients with the longest exposure to Actos, and in those with the highest cumulative dose of the drug.

Actos is in the same class of drugs as GlaxoSmithKline's Avandia, which has not been associated with bladder cancer but has been linked to heart risks.

The FDA has said patients should not stop taking Actos unless told to do so by their doctor.

To investigate the question further, Poluzzi and her colleagues reviewed reports of negative reactions submitted to the FDA's official Adverse Event Reporting System, launched in 1969.

It's an imperfect system, she and her colleagues note in the journal Diabetes Care - for one, manufacturers are required to report to the FDA any health problem they suspect stems from one of their products, but for doctors, patients, lawyers, and anyone else who reports these reactions, it's entirely voluntary. As a result, the number of FDA reports does not equal the true number of bad reactions to drugs.

The data are also influenced by what is known as "notoriety bias," Poluzzi added, in which the number of reports of bad reactions typically rises after warnings - such as a new study - suggest that they could occur.

However, the scientists also saw disproportionate cases of bladder cancer among Actos users in the years before a major 2005 study suggested that a link might exist.

It's not clear how Actos might increase the risk of bladder cancer, Poluzzi added. The drug treats diabetes by activating certain receptors on cells - much as a key opens or closes a lock, and this same mechanism may also encourage some cells to become cancerous, she said.

Bladder cancer is the sixth most common cancer in the U.S. According to the National Cancer Institute, there were about 70,000 new cases diagnosed nationwide in 2010, and close to 15,000 deaths from the disease.

"Until the final data of the FDA investigation are available, physicians should pay careful attention to this possible risk," Poluzzi and her colleagues write.

Source: http://bit.ly/fRMKux

Diabetes Care, online April 22, 2011.

Disruption of Nerve Cell Supply Chain May Contribute to Parkinson's

ScienceDaily

Friday, May 13, 2011

ScienceDaily (May 13, 2011) — New data offer hints to why Parkinson's disease so selectively harms brain cells that produce the chemical dopamine, say researchers at Washington University School of Medicine in St. Louis.

Dopamine is involved in brain cell communications including the signals that control movement. As Parkinson's kills the dopamine-producing cells, patients begin to develop tremors, problems moving and other symptoms.

The new research shows that a drug known to damage dopamine-producing nerve cells and mimic Parkinson's disease does so by rapidly damaging cellular energy generators called mitochondria. This damage impairs the ability of mitochondria to circulate around the cell as they normally would. As a result, axons, the extended arms nerve cells use to send messages, wither; a few days later, the body or main portion of the cell also dies.

"Much of the research into Parkinson's disease treatments is focused on saving the bodies of these cells, but our results suggest that keeping axons healthy also is essential,"says Karen O'Malley, PhD, of Washington University School of Medicine in St. Louis. "When axons die back, dopamine is no longer delivered to the neurons that need it. The cell body also has fewer connections to other cells, and it needs those connections to survive."

The results were published May 11 in The Journal of Neuroscience.

Many processes and facilities for cellular maintenance are in the body of the nerve cell, and their products sometimes have to travel a significant distance to reach the axon's end.

"If you think, for example, about one of your peripheral nerves, the cell body is located in the spinal column, but some of the axons extend as far as your big toe," says O'Malley, professor of neurobiology. "That's like the cell body sits in an office in St. Louis and the end of the axon is in Chicago."

O'Malley compares the axon's system for transporting supplies to a railroad. Mitochondria are part of the railroad's cargo. They supply the energy that allows the axon to do its work.

For the study, O'Malley gave cultured mouse nerve cells a toxin called MPP+ that causes Parkinson's-like symptoms.

"MPP+ is a derivative of a synthetic form of heroin developed in California in the early 1980s," O'Malley says. "It came to scientists' attention when teenage abusers of the drug went to the hospital with Parkinson's disease symptoms."

O'Malley found that the toxin stopped the movement of mitochondria in the axon in 30 minutes. The railroad still functioned, shipping other cargo to the end of the axon. But most mitochondria either stopped moving or were headed for the cell body instead of the axon.

O'Malley suspected that this meant the mitochondria were damaged by the changes caused by the toxin and being shipped back to the cell body for repair. Additional tests supported this theory, showing that the mitochondria had lost their ability to maintain their membrane potential, a measure of mitochondrial fitness.

The specificity of this toxin for dopamine-producing cells is reinforced by the finding that other types of nerve cells did not have problems transporting mitochondria after toxin exposure. In a comparison between different nerve cell types, O'Malley found mitochondria in dopamine-producing nerve cells are smaller in size and travel three times slower. But she can't yet definitively say that these distinctions play a role in the problems caused by the toxin.

Scientists screened several compounds to see if they could block the toxin's effects. Only two antioxidants worked, glutathione and N-acetyl cysteine. The latter compound has already been shown to be effective in animal models of Parkinson's disease and is used as a treatment for other disorders in patients.

O'Malley is currently studying whether two genes linked to Parkinson's disease affect mitochondria damaged by the toxin.

"We're going to continue to look for specific differences in these cells that might help scientists develop better treatments," O'Malley says.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

J. S. Kim-Han, J. A. Antenor-Dorsey, K. L. O'Malley. The Parkinsonian Mimetic, MPP , Specifically Impairs Mitochondrial Transport in Dopamine Axons. Journal of Neuroscience, 2011; 31 (19): 7212 DOI: 10.1523/JNEUROSCI.0711-11.2011

Gene Variant Linked to Sudden Cardiac Death Risk in Blacks

HealthDay News

Friday, May 13, 2011

FRIDAY, May 13 (HealthDay News) -- A common gene variant among black people may be linked to the development of life-threatening heart arrhythmias (when the heart beats too fast, too slow or irregularly), according to a new study.

In pinpointing this gene, Duke University Medical Center researchers hope to one day help doctors determine which patients are likely to benefit most from an implantable cardio-defibrillator (ICD) -- a device that automatically detects and corrects potentially deadly heart rhythms by delivering a jolt of electricity.

Blacks are disproportionately affected by heart failure, arrhythmias and sudden cardiac death, "but are vastly underrepresented in the majority of clinical trials conducted to date," the study's lead author, Dr. Albert Y. Sun, said in a university news release. "Much debate surrounds the identification of patients for ICD implantation, which takes into account efficacy, cost and complication rates."

The study, published in the current issue of the journal Circulation: Cardiovascular Genetics, included 112 black patients who received ICDs for primary prevention of sudden cardiac death. Over a follow-up period that averaged about two years, ICDs were effectively activated in 23 of the patients.

The investigators found that patients with the gene variant, known as the Y1103 allele, were three times more likely have the device triggered because of a potentially life-threatening ventricular arrhythmia. "These findings are significant because approximately 13 percent of people of African descent carry this variant," Sun noted.

Patients with the gene variant also experienced their first arrhythmia 448 days sooner than those without the gene (609 days versus 1,057 days). "This is the largest genetic study to date of blacks with ICDs and it promises potential new diagnostic strategies to define patients who will most benefit from ICDs," concluded the study's principal investigator, Dr. Geoffrey S. Pitt, director of Duke's Ion Channel Research Unit, in the news release.

More information

The American Heart Association offers detailed information on heart arrhythmias.

Thursday, May 12, 2011

Are C-sections fueling the obesity epidemic?

By Amy Norton

Reuters Health

Thursday, May 12, 2011

NEW YORK (Reuters Health) – Young adults born via Cesarean section are more likely to be obese than those delivered vaginally, suggesting C-sections could be feeding the obesity epidemic, researchers have found.

But the theory is controversial. One expert cautioned that scientists are still a long way from pinning the expanding waistlines on higher rates of C-sections.

In the new study, Brazilian researchers found that among more than 2,000 23- to 25-year-olds, 15 percent of those delivered via C-section were obese compared to 10 percent of those born naturally.

The team looked at a number of other factors that could potentially explain the connection, like heavier birth weight, or income and education levels (more-educated mothers had a higher C-section rate).

But even after accounting for these factors, C-section remained linked to a 58-percent increase in the risk of adulthood obesity, according Dr. Helena Goldani and colleagues.

The findings do not prove cause-and-effect, Goldani, of Universidade Federal do Rio Grande do Sul in Porto Alegre, told Reuters Health in an email. And there could still be other explanations for the finding, she said.

Still, it's possible that C-sections could directly affect the risk of becoming obese later in life, the researchers speculate.

That's because infants born via C-section are not exposed to the beneficial bacteria in the birth canal, and so they might take longer to accumulate Bifidobacteria and other microbes that could influence their metabolism.

Similarly, obese adults tend to have fewer of those friendly bacteria in their digestive tract than normal-weight people do.

A researcher not involved in the study said that while the theory is "interesting," this study offers no proof that C-sections are to blame.

"I think all they have shown is an association. They have not shown any mechanism or cause-and-effect," said Dr. Xavier Pi-Sunyer, director of the New York Obesity Research Center at St. Luke's Hospital.

A major weakness, he told Reuters Health, is that the study had no information on mothers' weight.

Obese women are more likely than thinner women to need a C-section. Likewise, they are more likely to have overweight or obese children.

"That is a huge gap in the data," Pi-Sunyer said.

He noted, though, that other researchers are looking into the question of why obese people tend to have a different composition of bacteria in the intestines than thinner people.

One theory is that the variation in intestinal bacteria comes first and contributes to obesity by causing people to burn fewer calories and store more as fat.

Whether that is the case remains uncertain, however, and the role of C-sections is even less clear.

"This is an interesting finding," Pi-Sunyer said. "But it raises more questions than it answers, and it requires a lot more research."

He said that future studies will have to account for more "confounding" factors, like mothers' weight and pregnancy-related diabetes, to show whether the link between C-sections and obesity is real.

Goldani agreed that further studies in other countries are needed -- including studies that measure newborns' intestinal bacteria, then follow them over time to chart their weight changes.

Brazil has long had one of the highest C-section rates in the world. Of the 2,057 adults in this study, who were born in the late 1970s, 32 percent were born via C-section. It's now estimated that C-sections are done in about 44 percent of Brazilian births, many of which are thought to be medically unnecessary.

The C-section rate is also high in the U.S., where it accounts for about 33 percent of births.

"An underlying message in this (report) seems to be that there should be fewer C-sections performed," Pi-Sunyer said.

That may well be, he added, but not because it will do anything to solve the obesity problem.

Source: http://bit.ly/laOPGb

American Journal of Clinical Nutrition, online April 20, 2011.

Lack of Exercise Linked to Higher Heart Disease Risk in Healthy Children as Young as 9

ScienceDaily

Thursday, May 12, 2011

ScienceDaily (May 12, 2011) — Even healthy children as young as 9 years old can start to show an increased risk of future heart problems if they are physically inactive, according to a study in the May issue of Acta Paediatrica.

A team of researchers from Sweden and Denmark studied 223 children -- 123 boys and 100 girls -- with an average age of 9.8 years, assessing their physical activity levels over four days.

They found that the children who were more physically active had a lower composite risk factor score for cardiovascular disease (CVD) than the children with lower amounts of moderate to vigorous physical activity and vigorous physical activity.

"It is well known that physical inactivity in adults is associated with a wide range of diseases and all causes of death" says lead author Dr Tina Tanha from the Department of Clinical Sciences at Skane University Hospital in Malmo, Sweden.

"We believe that our study now demonstrates a clear clinical association between physical inactivity and multiple CVD risk factors in children. It reveals that up to 11 per cent of the variance in composite CVD risk factor scores in the children could be explained by differences in their physical activity."

The children wore an accelerometer strapped to an elastic waist belt for four consecutive days to measure physical activity levels, using parameters set by two large accelerometer studies. Children were only included in the study if they wore the belt for a minimum of eight hours a day for three days. They also underwent tests for various CVD risk factors, including blood pressure, resting heart rate, fitness and body fat.

Key findings included:

The children's average body mass index was 17.5 for the girls and 17.4 for the boys.

The boys were significantly more physically active than the girls, with higher levels of general physical activity (746 mean counts per minute versus 620), moderate to vigorous physical activity (45 minutes versus 35 minutes) and vigorous physical activity (15 minutes versus 11 minutes).

There were no significant differences between the genders when it came to systolic and diastolic blood pressure, mean arterial pressure and pulse pressure. However the resting heart rate was significantly higher in the girls (85 versus 80 beats per minute).

The boys had lower total body fat mass than the girls (6.3kg versus 8.3kg) and lower percentage body fat (16.2 per cent versus 22.6 per cent), but a higher peak oxygen uptake (41.7mL/min/kg versus 35.7).

Vigorous physical activity accounted for ten per cent of the variance in the accumulated cardiac risk scores and moderate to vigorous physical activity accounted for eight per cent of the variance. The results were similar for boys and girls.

But there was a difference when it came to general physical activity. This accounted for 11 per cent of the variance in the boys, but showed no significant variance in the girls.

"Previous research into CVD risk factors in children have focused on quite specific single risk factors, but our study covers multiple risk factors" explains Dr Tanha.

"Our results show a significant association between low levels of activity and high composite risk factors for CVD, even in young children. Much of the association was driven by body fat measurements and oxygen intake.

"This is important because the accumulation of these risk factors, if started in early childhood and sustained over a long period, is believed to have greater impact on CVD and mortality than one single risk factor."

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Tina Tanha, Per Wollmer, Ola Thorsson, Magnus K. Karlsson, Christian Lind้n, Lars B. Andersen, Magnus Dencker. Lack of physical activity in young children is related to higher composite risk factor score for cardiovascular disease. Acta Paediatrica, 2011; 100 (5): 717 DOI: 10.1111/j.1651-2227.2011.02226.x

People with diabetes more likely to get cancer

By Kerry Grens

Reuters Health

Thursday, May 12, 2011

NEW YORK (Reuters Health) – People with diabetes are at higher risk for certain cancers than those without the blood sugar disease, suggests a new study.

Based on data from a telephone survey of nearly 400,000 adults, researchers found 16 out of every 100 diabetic men and 17 out of every 100 diabetic women said they had cancer.

That compares to just seven per 100 men and 10 per 100 women without diabetes.

"The significant association between cancer and diabetes does not surprise us," said Dr. Chaoyang Li, an epidemiologist at the Centers for Disease Control and Prevention in Atlanta, Georgia, whose findings appear in the journal Diabetes Care.

According to the CDC, nine percent of U.S. adults have diabetes.

After taking into account things like age, race, smoking and drinking habits, the researchers concluded that diabetic men and women were 10 percent more likely to have had a cancer diagnosis of any kind.

Li told Reuters Health other studies have also found a link between the two diseases, although there is no proof that one causes the other.

The researchers found that the types of cancers that were more likely among diabetics differed between men and women.

Compared to people without diabetes, diabetic men were more likely to report having colon, pancreas, rectum, urinary bladder, kidney or prostate cancer (the latter only occurs in men). Diabetic women had more cases of breast cancer, leukemia or cancer of the womb.

For men, the greatest increase in risk was for pancreatic cancer, with 16 per 10,000 cases among diabetics and just two per 10,000 among non-diabetics.

That corresponds to a four-fold difference after taking other factors into account.

Women's risk of leukemia also varied greatly between the two groups. One per 1,000 women without diabetes said they had been diagnosed with the blood cancer, compared to three per 1,000 women with diabetes.

This new study is just a snapshot of people's medical history, and does not follow them over time.

Dr. Fred Brancati, a professor at Johns Hopkins University in Baltimore, said he was struck by the findings, because some of the cancers kill people fast, meaning they wouldn't show up in the study.

"It shows there's a substantial pool of American adults who have diabetes and cancer," said Brancati, who was not involved in the study. "The authors rightly point out that these two conditions go together beyond chance alone, so it pays to think about them together."

Brancati's own research has shown that the risk of death from cancer among people with diabetes is about 40 percent higher than among non-diabetics (see Reuters Health report, December 16, 2008).

Li said it's still unclear why diabetes is tied to cancer. High blood sugar levels or excess blood insulin -- a hormone that helps ferry sugar into the cells -- might increase the risk, but that has not been proven.

Certain lifestyle choices reduce the risk of both diabetes and cancer, such as maintaining a healthy weight and not smoking.

Li said the findings are an important reminder for people with diabetes and their doctors to meet regular cancer screening guidelines and to discuss any possible cancer risk from anti-diabetic therapy.

Source: http://bit.ly/kzUQMN

Diabetes Care, online April 19, 2011.

New Discoveries About Tumor-Suppressing Protein Could Help Reduce Treatment Side Effects

ScienceDaily

Thursday, May 12, 2011

ScienceDaily (May 12, 2011) — Researchers at the Stanford University School of Medicine have untangled two distinct ways in which a common, naturally occurring "tumor-suppressor" protein works. The separation of these two functions -- which can have quite different consequences -- could enhance efforts to develop treatment approaches that mitigate the sometimes-devastating side effects of radiotherapy and chemotherapy.

The protein, p53, is mutated or missing in more than half of all human cancers, and most cancers involve at least some compromise in its function.

Cancer is caused by two categories of mutations: those that activate oncogenes, whose protein products drive cells into overzealous replication, and those that disable tumor-suppressor genes, which code for proteins that sense this abnormal behavior and put the brakes on it.

"We knew that p53 responds to two different types of signals: DNA damage and oncogene activity," said Laura Attardi, PhD, associate professor of radiation oncology and of genetics. "We wanted to know if p53 responds to both in the same way." Attardi is senior author of a study to be published May 13 in Cell that throws light on crucial molecular details about how p53 works.

It is widely understood that p53 can temporarily or permanently shut down cell division in response to either acute damage to a cell's DNA or biochemical signals within a cell that suggest it's prone to becoming a cancer cell. In extreme cases, p53 convincingly counsels the cell to commit suicide, thereby preventing the possibility of a tumor arising.

Attardi and her colleagues created bioengineered mice in which various parts of p53 were incapacitated. This allowed them to determine which genes are activated by different parts of the protein, and to show that p53's aggressive DNA-damage response and its gentler tumor-suppression response are separable functions.

"We've determined, for the first time, that the gene expression program p53 requires in its tumor-suppression role is distinct from that which it requires in the context of acute DNA damage," Attardi said. "Separating these responses may allow the identification of ways to inhibit the detrimental effects of radiotherapy and chemotherapy -- both of which damage DNA -- without putting a patient at risk for developing new tumors."

While most tumors lack a working p53 protein, radiotherapy and chemotherapy activate the p53 present in healthy tissues, producing serious side effects by destroying cells in the gastrointestinal tract, blood, hair follicles and brain. That's because these treatments cause profound DNA damage, a trigger for p53 action.

It's known that p53 is a transcription factor: a protein that can regulate the production of numerous other proteins inside a cell. According to scientists, p53 recognizes and perches upon a particular DNA sequence found near large numbers of genes. Once p53 has seated itself near such a gene, two different regions of the protein, called TAD1 and TAD2, can serve as landing beacons that attract mammoth molecular copying machines to the gene -- a key early step in protein generation.

But the response is very different depending on which of the two beacons, TAD1 or TAD2, is calling in the copying machinery.

Attardi's group used bioengineered mice in which TAD1, TAD2 or both had been disabled by mutations. This allowed the investigators to show that these two beacons flag different sets of genes.

The genes that TAD1 turns on are the ones involved in p53's show-stopping response to DNA-damage. More than 100 such genes had already been identified.

But when the investigators disabled TAD1 while leaving TAD2 intact, they were able to unmask a set of 50 or so genes turned on by TAD2. These genes, the team showed, mediate p53's ability to stimulate cells' somewhat more nuanced tumor-suppression response, which shuts down a cell only upon sensing oncogene activity, a more direct sign of potential cancer than mere DNA damage.

"When we treated the TAD1-disabled mice with high-dose radiation, they didn't suffer the DNA-damage-induced side effects that we saw in wild-type mice," said the study's lead author, Colleen Brady, a PhD student in Attardi's lab. "But TAD1-disabled mice were resistant to tumor development."

"This is an important advance," said molecular biologist and oncologist Arnold Levine, PhD, a professor at the Institute of Advanced Studies in Princeton, N.J. "The team has uncovered half of what the biggest player in human cancers does." Levine, who didn't participate in the study but is familiar with it, is one of three scientists credited for p53's discovery in 1979.

The finding that p53 can suppress tumors, even when the part of it that shuts down cells in response to DNA damage has been disabled, holds significant implications for therapy. If the two distinct activities of p53 in healthy cells can be decoupled -- say, by a drug impairing TAD1's function but sparing TAD2's -- it might be possible to avoid the massive healthy-cell die-off responsible for nausea, hair loss, immune deficiency and nerve damage that usually occur during radiotherapy or chemotherapy, without promoting new tumor development. Disabling p53's TAD1 region would allow cells that have sustained DNA damage in the course of these therapies to live to another day, but TAD2's still-intact tumor-suppressor function in those otherwise normal cells would guard against those cells becoming cancer cells.

The study was funded by the American Cancer Society, the Leukemia & Lymphoma Society and the National Institutes of Health. Other Stanford co-authors were postdoctoral researchers Dadi Jiang, PhD; Stephano Spano Mello, PhD; Daniela Kenzelmann Broz, PhD; Lesley Jarvis, MD, PhD; and Shashwati Basak, PhD; medical students Margaret Kozak and Thomas Johnson, PhD; and research assistant Eunice Park, all of Attardi's lab. Jarvis is now an assistant professor of medicine at Dartmouth-Hitchcock Medical Center, and Basak is scientific manager at BBRC Syngene International Ltd.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Colleen A. Brady, Dadi Jiang, Stephano S. Mello, Thomas M. Johnson, Lesley A. Jarvis, Margaret M. Kozak, Daniela Kenzelmann Broz, Shashwati Basak, Eunice J. Park, Margaret E. McLaughlin et al. Distinct p53 Transcriptional Programs Dictate Acute DNA-Damage Responses and Tumor Suppression. Cell, Volume 145, Issue 4, 571-583, 13 May 2011 DOI: 10.1016/j.cell.2011.03.035

Wednesday, May 11, 2011

Do bedbugs carry superbugs?

By Julie Steenhuysen

Reuters

Wednesday, May 11, 2011

CHICAGO (Reuters) – Researchers in Canada have found bedbugs carrying antibiotic-resistant superbugs, a surprise finding because scientists had thought the pests were not capable of spreading infections.

The study was done by a team in a poor corner of Vancouver, where both bedbug infestations and strains of antibiotic resistant bacteria are increasing.

Dr. Marc Romney, a medical microbiologist at St. Paul's Hospital/Providence Health Care in Vancouver, decided to see if the two were related.

Romney and colleagues removed five of the pests from the clothes and skin of infested patients and tested them.

They found bedbugs carrying two types of drug-resistant bacteria, methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci.

"I was a little surprised. Historically, bedbugs have not been associated with infections," Romney said in a telephone interview.

He said scientists have tested bedbugs to see if they carry blood-borne diseases, such as hepatitis or HIV. But so far, they have not been reported to carry infection.

Infestations of the bloodsucking bugs, which can cause severe itching, have made a comeback in cities such as Paris and New York in recent years.

Romney said the strain of MRSA they found requires skin to be somewhat compromised, and he thinks the bedbugs are providing that as people scratch their bites.

"Maybe the bedbug's bite is breaking down the patient's skin," he said.

He said that some of these pests may be carrying MRSA and going from individual to individual.

"The data are preliminary, but it suggests maybe there is an association," Romney said.

"Even though they can't carry hepatitis B and HIV, maybe they can carry resistant bacteria."

"Maybe it is yet another factor that could be responsible for this large increase in resistant bacteria in inner cities in North America," he said.

(Editing by Mohammad Zargham)

Selenium doesn't prevent cancer: report

By Genevra Pittman

Reuters Health

Wednesday, May 11, 2011

NEW YORK (Reuters Health) – There is no convincing evidence that taking high doses of selenium -- a popular dietary supplement -- can prevent cancer, according to a new review.

Selenium is a mineral that is essential for humans, and is also present in soil and rocks.

While daily selenium recommendations from the United States and World Health Organization vary between 30 and 55 micrograms per day for adults, the authors note, companies that sell the supplements claim that higher doses have a range of health benefits, including cancer prevention.

However, "we still do not have an exact picture of what selenium is doing to human health," Dr. Marco Vinceti, one of the authors of the new review from the University of Modena and Reggio Emilia in Italy, told Reuters Health.

To try to get a better focus on that picture for cancer in particular, Vinceti and his colleagues analyzed 55 studies on the link between selenium and different types of cancer.

Most of those were so-called "observational studies" -- scientists measured how much selenium people ate every day or how much they had in their blood or toenails, then tracked who got cancer over the next few years.

The remaining 6 studies were done through more rigorous trials, in which researchers randomly divided participants into one group that took selenium supplements for a month or more, and another that took a drug-free placebo pill or nothing -- then followed them for cancer. These kinds of studies are thought to be better at accounting for outside factors that may affect cancer risk.

The observational studies suggested that talking selenium may be linked to a slightly lower risk of cancer -- more so in men than women.

But in the randomized trials, people assigned to take selenium at doses at least four times higher than the daily recommendation were not less likely to get cancer -- prostate cancer and skin cancer, in particular -- than those not taking selenium.

And some of those trials raised the question of whether high doses of selenium might be dangerous, such as by increasing the risk of diabetes.

The review is published in the Cochrane Library, a publication of the Cochrane Collaboration, an international organization that evaluates medical research.

"If you put it all together, it's not a good story for patients," Dr. Neil Fleshner, a researcher at University Health Network in Toronto who has studied the effect of selenium on prostate cancer risk, told Reuters Health.

He said it's still possible that selenium may help prevent cancer over a very long time period, or that certain kinds of selenium might work while others don't. But right now, "there's no good evidence at all that selenium is beneficial," said Fleshner, who was not involved in the review.

James Marshall, of the Roswell Park Cancer Institute in Buffalo, said that the excitement about selenium began with evidence that animals or people with very low selenium in their diet are at an increased risk for cancer.

While those individuals might benefit from a selenium supplement, that's where the mineral's anti-cancer effects appear to end.

"Once you get an animal or a person up to a place where selenium intake is adequate, then, this is where the evidence has proven disappointing," Marshall, who was not linked to the new research, told Reuters Health.

"Putting them on more selenium is not going to do them any good, and it may in fact harm them," Marshall said.

Vinceti said that while few people in Europe take selenium as a supplement, it's common in the United States.

Selenium supplements are about $2 for a month's supply.

Vinceti added that more research is needed to determine the range of daily selenium that is beneficial to human health -- as both too much and too little appear to have health risks. In that regard, "we are not at the end of the story," he said.

But when it comes to preventing cancer, at least for now, the evidence is not there.

"There are many ways of preventing cancer, but putting more selenium ...on your breakfast cereal, is probably not one of them," Marshall concluded.

Source: http://bit.ly/iqHcFo

The Cochrane Library, online May 10, 2011.

Scientists Find MRSA Germ in Supermarket Meats

By Steven Reinberg
HealthDay Reporter

HealthDay News

Wednesday, May 11, 2011

WEDNESDAY, May 11 (HealthDay News) -- MRSA, a bacteria resistant to common antibiotics, has been discovered in supermarket meats, and the germ is apparently being introduced by human food handlers, a new study reports.

Although thorough cooking will kill the bacteria, consumers run the risk of infection if they handle meats contaminated with the germ, researchers said.

MRSA (methicillin-resistant Staphylococcus aureus) is common in hospitals and nursing homes, where it can cause serious illness and even death. And so-called "community-acquired MRSA" has become a problem among some high school and college athletes who share equipment; this type of MRSA appears as a skin infection and is usually less serious, according to the U.S. Centers for Disease Control and Prevention.

It's the community-acquired MRSA that was found in the meats, the researchers said.

"MRSA has always been found in human patients, but we found this in retail meat, so retail meat can be a reservoir of these bugs," said study lead researcher Yifan Zhang, an assistant professor in the department of nutrition and food science at Wayne State University in Detroit.

"When people handle food, they can get the bugs from the meat if the meat is already contaminated," she explained.

The risk of becoming infected is especially high if you have open cuts or sores on your hands or skin, Zhang added.

"When you handle food, especially if you have wounds on your hands, wear gloves to protect yourself from getting MRSA infection," she said.

The researchers found a human strain of MRSA in meats, so people can also transfer the bacteria to meat, she added.

Contamination can occur if carriers of MRSA handle meat or if there is MRSA in the environment, which might happen in meat processing plants, Zhang added.

The report was published in the May 11 online edition of the U.S. Centers for Disease Control and Prevention's journal Emerging Infectious Diseases.

For the study, Zhang's team purchased 289 raw meat samples, including 156 beef, 76 chicken and 57 turkey samples, from 30 grocery stores in Detroit from August 2009 through January 2010.

The researchers found that 22.5 percent of the samples were contaminated with S. aureus and six samples tested positive for MRSA. Of the six samples contaminated with MRSA, two were beef, three were chicken and one was turkey, the researchers said.

The extent of MRSA contamination in meat varies by the type of meat and where the meat was processed, Zhang said.

Zhang thinks that MRSA in meat results from contact by people carrying the bacteria. Another recent study found that the strain of MRSA in meat in the United States is not the strain found in animals, she noted. That strain is found more commonly in Europe, she added.

However, the animal strain of MRSA has been found in live pigs in the United States, so it may appear in the food chain in the future, the researchers added.

Dr. Marc Siegel, an associate professor of medicine at New York University, said that "MRSA is a big problem and appears to be invading our meat."

Siegel also believes that the MRSA contamination Zhang's group found is most likely from infected people handling the meat.

Another factor is the overuse of antibiotics in the raising of livestock. This, Siegel explained, could create antibiotic-resistant animals that are more likely to be susceptible to bacteria such as MRSA.

"The combination of the overuse of antibiotics and the fact that MRSA is becoming more prominent in the human population explains this," he said.

In addition to taking other precautions when handling meat, MRSA is killed when the meat is cooked thoroughly, Siegel added.

Siegel also suggested washing plates or utensils used to prepare food before using them again to eat. And, it is important to disinfect counters that have come into contact with meats, he advised.

These precautions would also kill off any other S. aureus, which "we don't need in our meat either," Siegel said.

On a positive note, another report in the same journal issue finds that efforts to reduce bacterial contamination of chicken from campylobacteriosis have resulted in a 50 percent drop in what was an epidemic in New Zealand.

More information

For more information on MRSA, visit the U.S. National Library of Medicine.

Celebrex may curb colon cancer, but with caveats

By Alison McCook

Reuters Health

Wednesday, May 11, 2011

NEW YORK (Reuters Health) – People who took a newer type of pain pill over a three-year period were less likely to develop polyps that could lead to colorectal cancer -- but at the expense of a higher risk of heart problems, new study findings report.

And when participants stopped taking the pain pill Celebrex (celecoxib) out of concerns over side effects, they eventually developed more polyps than people who had remained on an inactive, or placebo, drug throughout the study.

So should people concerned about their risk of colorectal cancer consider Celebrex?

"The findings in this study don't necessarily make that decision any easier," said Dr. Andrew Chan of Massachusetts General Hospital and Harvard Medical School, who did not participate in the research.

The study, published in the American Journal of Gastroenterology, received financial support from Pfizer, which sells Celebrex.

This is not the first study to suggest Celebrex and similar drugs -- known as COX-2 inhibitors - may reduce the risk of developing colon cancer, he said, but people need to balance that potential benefit with the higher risk of cardiovascular complications.

As a result, he said he suspects most people would choose to rely on regular colonoscopies to catch the disease in its early stages, rather than take a potentially risky drug for years.

But to people who have no underlying cardiovascular problems and a particularly high risk of colon cancer - they were diagnosed with it before perhaps, or have a strong family history - regular screening may not be enough, Chan noted.

"So for those patients, they might consider taking a drug like this," he said.

Colorectal cancer is the third most common cancer in men and women, and strikes 1.2 million people each year.

Other research has provided signs that COX-2 inhibitors, which block the COX-2 enzyme that causes inflammation, could also prevent colorectal cancer, as well as lung cancer in heavy smokers.

However, most COX-2 inhibitors ran into safety issues a few years after their approval, and now only Celebrex remains on the U.S. market. At a cost of several dollars per day, depending on dosage, it is much more expensive than older pain relievers such as ibuprofen.

During the study, Dr. Nadir Arber of Tel Aviv University and his colleagues reviewed data collected from 1,561 people with a history of colorectal cancer. More than half had received Celebrex for approximately 3 years, before concerns over the increased risk of cardiovascular problems caused researchers to discontinue the study.

The scientists then followed the people willing to continue the research for another 2 years, noting who developed new polyps, including advanced polyps with features that suggest they're more likely to become cancerous. Approximately half of the people who started the study agreed to continue.

Not surprisingly, Celebrex users were more likely to develop cardiovascular problems, including a 66 percent higher risk of serious cardiac disorders. But over the total 5-year period, people who took Celebrex were also less likely to develop new and advanced polyps than people who took a placebo.

Specifically, new polyps were found in 58 percent of people on placebo, and only 51 percent on Celebrex.

However, during the 5th year of the study alone, after the trial had been over for 2 years, 27 percent of Celebrex users developed new polyps, versus only 16 percent of people who had been on placebo - translating to a 66 percent higher risk among those who previously took Celebrex. Those who had been on Celebrex were also more likely to develop advanced polyps during that final year.

This rebound in risk actually makes biological sense, Chan told Reuters Health. If COX-2 inhibitors protect against colon cancer by blocking an enzyme pathway, when that blockage is released, the disease could occur "potentially at higher levels than had you never been on the drug in the first place," he said.

Still, the results are "very promising," Arber told Reuters Health by e-mail, adding he is now working to identify people who could benefit from the drug without experiencing the side effects.

Only half of the people who originally agreed to participate in the study remained after 5 years, and it's unclear how this might affect the results, noted Chan, whose own research suggests aspirin could prevent deaths from colorectal cancer.

However, for a study that lasts this long, "those are acceptable numbers," noted Arber.

If patients asked him whether they should take celecoxib to prevent colorectal cancer, Arber would tell them "no," he added. "They should speak with their doctor."

Source: http://bit.ly/mDNurd

The American Journal of Gastroenterology, online April 19, 2011.

Mild Obesity Appears to Improve Survival in Amyotrophic Lateral Sclerosis Patients

ScienceDaily

Wednesday, May 11, 2011

ScienceDaily (May 11, 2011) — Patients with amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, may be an exception to the rule that being overweight is a health hazard. In a retrospective study of over 400 ALS patients, Massachusetts General Hospital (MGH) researchers found that those who were mildly obese survived longer than patients who were normal weight, underweight or even overweight. The study will appear in the journal Muscle & Nerve and has been published online.

“We have long known that being underweight shortens survival for ALS patients, and several studies in an animal model have shown that weight gain is associated with increased survival," says Anne-Marie Wills, MD, MPH, of the MGH Neurology Clinical Trials Unit, senior author of the report. "Our study was designed to investigate how cholesterol levels affect survival. We were surprised to find that body mass index or BMI -- a measure of weight adjusted for height -- made a large difference in survival. Patients with a BMI of 30 to 35, who would be considered mildly clinically obese, lived the longest; and patients who were overweight, with a BMI of 25 to 30, lived the second longest."

ALS is a progressive neurodegenerative disease affecting motor neurons in the brain and spinal cord. Death of these nerve cells stops the transmission of neural impulses to muscle fibers, leading to weakness, paralysis and usually death from respiratory failure. During the course of their disease ALS patients usually lose even more weight than can be attributed to the loss of muscle mass caused by nerve destruction and the related muscle inactivity. Studies have shown that ALS patients burn more calories than would be expected from their limited physical activity, but the mechanism for this metabolic change is currently unknown.

A previous smaller study suggested that ALS patients with higher levels of low-density lipoprotein (LDL) relative to high-density lipoprotein (HDL) might live longer. In order to test that association in a larger group of patients, the MGH team analyzed data on more than 400 patients who had participated in three clinical trials of potential ALS drugs. Along with the results of initial blood tests taken when participants entered the trials, the researchers had access to follow-up blood tests for almost 200 participants and information on how long each patient survived without needing mechanical ventilation assistance.

Depending on the particular clinical trial, survival data was available for one to two years after study initiation. While higher baseline cholesterol levels were associated with longer survival, that association disappeared when the results were controlled for BMI. As expected, the shortest survival was seen in malnourished or morbidly obese patients, but patients in the mildly obese range had the longest survival of any BMI group.

"While this finding needs further investigation, we hypothesize that it is due to increased energy reserves available to these patients," says Wills, an instructor of Neurology at Harvard Medical School. "We don't know whether actively putting on weight would be helpful, but right now I'm telling my patients with ALS they can eat anything they want."

The lead author of the Muscle & Nerve study is Sabrina Paganoni, MD, PhD, of Spaulding Rehabilitation Hospital. Additional co-authors are Jing Deng, Matthew Jaffa and Merit Cudkowicz, MD, MSc, all of MGH Neurology. The study was supported by the Muscular Dystrophy Association and the Digiovanni ALS Research Fund.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Sabrina Paganoni, Jing Deng, Matthew Jaffa, Merit E. Cudkowicz, Anne-Marie Wills. Body mass index, not dyslipidemia, is an independent predictor of survival in ALS. Muscle & Nerve, 2011; DOI: 10.1002/mus.22114

Shed Skin in Dust May Reduce Indoor Air Pollution

HealthDay News

Wednesday, May 11, 2011

WEDNESDAY, May 11 (HealthDay News) -- The flakes of human skin in household dust may help reduce indoor air pollution, according to new research.

Humans shed their entire outer layer of skin every two to four weeks, the researchers pointed out in the study, published in the May issue of the journal Environmental Science & Technology. Those flakes, which contain skin oils such as cholesterol and squalene, are a major contributor to dust buildup in homes and offices.

The Danish researchers reported that squalene oil, the most common fat and antioxidant found on human skin, plays a small role in reducing levels of indoor ozone, a pollutant that can irritate the eyes, nose and throat and exacerbate asthma symptoms.

"It is only within the last five years that we've grown to appreciate the central role that squalene (from human skin oil) plays in oxidation chemistry within indoor environments," the study authors said in a news release from the American Chemical Society.

The researchers examined how cholesterol and squalene from dust in 500 bedrooms of children aged 3 to 5 years and their daycare centers affected indoor air pollution. They found that squalene in settled dust reduced ozone levels roughly 2 to 15 percent.

Previous studies also revealed that squalene from human skin helped lower levels of ozone from the air in airplane cabins. "More than half of the ozone removal measured in a simulated aircraft cabin was found to be a consequence of ozone reacting with exposed, skin, hair, and clothing of passengers," Charles Weschler and colleagues wrote in the news release.

More information

The U.S. Environmental Protection Agency provides tips for controlling indoor air pollution.

Before You Start Bone-Building Meds, Try Dietary Calcium and Supplements, Experts Urge

ScienceDaily

Wednesday, May 11, 2011

ScienceDaily (May 11, 2011) — Has a bone density scan placed you at risk for osteoporosis, leading your doctor to prescribe a widely advertised bone-building medication? Not so fast! A University of Illinois study finds that an effective first course of action is increasing dietary calcium and vitamin D or taking calcium and vitamin D supplements.

"For many people, prescription bone-building medicines should be a last resort," said Karen Chapman-Novakofski, a U of I professor of nutrition and co-author of a literature review published in a recent issue of Nutrients.

The study reported that adults who increase their intake of calcium and vitamin D usually increase bone mineral density and reduce the risk for hip fracture significantly. These results were often accomplished through supplements, but food is also a good source of these nutrients, she said.

"I suspect that many doctors reach for their prescription pads because they believe it's unlikely that people will change their diets," she noted.

The scientist said that prescription bone-building medications are expensive, and many have side effects, including ironically an increase in hip fractures and jaw necrosis. They should be used only if diet and supplements don't do the trick.

"Bisphosphonates, for instance, disrupt normal bone remodeling by shutting down the osteoclasts -- the cells that break down old bone to make new bone. When that happens, new bone is built on top of old bone. Yes, your bone density is higher, but the bone's not always structurally sound," she said.

A bone density test measures quantity, not quality, of bone. "Although the test reports that you're fine or doing better, you may still be at risk for a fracture," said Chapman-Novakofski.

A woman in midlife can get enough calcium in her diet without gaining weight, said lead author Karen Plawecki, director of the U of I's dietetics program.

"Menopausal women should consume 1,200 milligrams of calcium a day. Three glasses of 1 percent to skim milk will get you up to 900 milligrams. The rest can easily be obtained through calcium-rich and calcium-fortified foods," Plawecki said.

According to Plawecki, the number of foods fortified with calcium and vitamin D is increasing exponentially. Examples are soy milk, orange juice, yogurt, crackers, cereal, bread, breakfast bars, and even pancakes.

The researchers also looked at the effects of dietary protein, vitamin K, soy, and sodium in their literature review. The new USDA food pyramid guidelines recommend that Americans decrease their sodium intake.

"Following a low-sodium diet does seem to have a positive effect on bone density. Some people have the habit of adding a generous sprinkle of salt to most foods before eating, but there's more involved here than learning not to do that. You have to choose different foods," Plawecki said.

Smoked or processed meats, bacon, lunch meat, and processed foods all contain a lot of sodium and could sabotage bone health. "Cheese is also very high in sodium so try to get your calcium some other way more often," Plawecki said.

She recommends a "portfolio diet" that contains a number of nutrients, not just extra calcium and vitamin D. For bone health, the researchers also encourage consuming adequate protein, less sodium, and more magnesium and potassium.

"That can be done by following a diet that's high in fruits and vegetables, has adequate calcium and protein, and is light on salt," she said.

Chapman-Novakofski noted that the National Osteoporosis Foundation recommends more physical activity. She suggests a combination of aerobic, strength, balance, and flexibility exercises with a focus on improving your core muscles so you can catch yourself if you start to fall.

Whatever sort of exercise you're doing, you have to introduce new forms of activity every so often because your bones will stop responding to the same old routine and rebuilding will slow, she said.

Plawecki and Chapman-Novakofski set out to determine the impact of dietary, supplemental, and educational interventions over the last 10 years and reached their conclusions after reviewing 219 articles in scientific journals.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Karen Plawecki, Karen Chapman-Novakofski. Bone Health Nutrition Issues in Aging. Nutrients, 2010; 2 (11): 1086 DOI: 10.3390/nu2111086

Tuesday, May 10, 2011

Vitamin D May Prevent Serious Respiratory Disease in Newborns

By Steven Reinberg
HealthDay Reporter

HealthDay News

Tuesday, May 10, 2011

TUESDAY, May 10 (HealthDay News) -- Vitamin D supplements for pregnant women may help prevent a respiratory disease called RSV that can lead to pneumonia and other potentially life-threatening illnesses in newborns, Dutch researchers report.

Respiratory syncytial virus (RSV) is the most common cause of pneumonia and inflammation of the lower airways (bronchiolitis) in infants in the United States, according to the U.S. Centers for Disease Control and Prevention. While most children recover, many are hospitalized and develop respiratory problems that persist well into childhood.

"We have no treatment for RSV. The only thing we can do is try to prevent the disease," said lead researcher Dr. Louis Bont, from the department of pediatric infectious diseases at Wilhelmina Children's Hospital and University Medical Center in Utrecht.

One way to prevent RSV is for pregnant women to take supplemental vitamin D, he said. "In fact, there are guidelines that prescribe that," he added.

"If pregnant women do not take vitamin D supplements, they have low vitamin D levels in the umbilical cord blood and then the children have a severely increased risk of RSV," Bont said.

"Intake of vitamin D during late stage of pregnancy is vital to prevent RSV, and probably other respiratory diseases as well," he concluded.

RSV infects about 5 million children in the United States each year. But if women took vitamin D supplements during pregnancy, about 20 percent of those infections in newborns might be prevented, Bont said. "That would be in the magnitude of 1 million cases per year," he said.

Vitamin D has many important functions, Bont explained, noting that "it shapes and matures the immune system." In addition, the vitamin plays a role in helping the respiratory system develop, he added.

The report was published in the May 9 online edition of Pediatrics.

For the study, Bont's team measured the amount of vitamin D in the umbilical cord blood of 156 newborns in the Netherlands.

The researchers found 54 percent of these newborns had insufficient levels of vitamin D. Among these infants, 18 (12 percent) developed RSV in the first year of life.

In fact, infants with low levels of vitamin D were six times more likely to develop RSV, compared with infants who had the highest levels, Bont's group found.

Among the women in the study, only 46 percent said they took supplements containing vitamin D while they were pregnant, the researchers noted.

Bont thinks all pregnant women should be taking vitamin D supplements. In general, they should be getting 400 to 1,000 International Units (IU) a day, he said.

In the study, Bont and other researchers explained that some pregnant women might need up to 4,000 IU a day to achieve the best outcome for their infants. (Experts who make up the U.S. Food and Nutrition Board recommend that pregnant women get at least 600 IU of vitamin D daily and note that they can safely take up to 4,000 IU a day, according to the U.S. Office of Dietary Supplements.)

The cost of prenatal vitamins, which contain vitamin D, is about $9 a month.

What the researchers have shown in this study is an association between vitamin D and preventing RSV. To establish a cause-and-effect relationship, Bont said that randomized trials are needed.

Dr. Andrew Colin, director of the division of pediatric pulmonology at the University of Miami Miller School of Medicine, said this finding could "save the world a humongous amount of money."

Colin noted the recognition of the link between low vitamin D levels and lung diseases has been growing over the years. This is particularly true for asthma. In fact, the increase in the number of asthma cases can, in part, be attributed to low vitamin D levels, he said.

"RSV is a worldwide scourge," Colin said. "Probably the most significant lung disease of infancy is RSV. The bad news about this disease is that quite a few infants who have had RSV infection will develop an asthma-like disease, which can affect their entire childhood," he added.

Colin thinks vitamin D may very well prevent RSV. "If, indeed, boosting the vitamin D in the mothers is going to end up with high vitamin D in babies [and] is going to make a difference, I think it's huge," he said.

This concept needs to be tested, Colin said, but added that he thinks it is fine for pregnant women to take supplemental vitamin D now. "I can't see the downside," he said.

More information

For more information on respiratory syncytial virus (RSV), visit the U.S. Centers for Disease Control and Prevention.

Vitamin D Deficiency in Pneumonia Patients Associated With Increased Mortality

ScienceDaily

Tuesday, May 10, 2011

ScienceDaily (May 10, 2011) — A new study published in the journal Respirology reveals that adult patients admitted to the hospital with pneumonia are more likely to die if they have vitamin D deficiency.

Vitamin D is known to be involved in the innate immune response to infection.

The team of researchers at Waikato Hospital and the Universities of Waikato and Otago, measured vitamin D in the blood samples of 112 adult patients admitted with community acquired pneumonia during the winter at the only acute-care hospital in Hamilton, New Zealand.

The researchers found that vitamin D deficiency was associated with higher mortality within the first 30 days after hospital admission for pneumonia. The association between vitamin D deficiency was not explained by patient age, sex, comorbidities, the severity of the systemic inflammatory response, or other known prognostic factors.

The authors conclude that "improved understanding of Vitamin D and its role in immunity may lead to better ways to prevent and/or treat pneumonia. We now need to investigate whether Vitamin D supplements could be a useful addition to pneumonia treatment and whether using supplements could help to prevent or reduce the severity of pneumonia among high-risk populations."

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Leong Leow, Talia Simpson, Ray Cursons, Noel Karalus, Robert J. Hancox. Vitamin D, innate immunity and outcomes in community acquired pneumonia. Respirology, 2011; 16 (4): 611 DOI: 10.1111/j.1440-1843.2011.01924.x

Research Suggests 1 in 7 Strokes Happens During Sleep

HealthDay News

Tuesday, May 10, 2011

TUESDAY, May 10 (HealthDay News) -- About 14 percent of strokes happen while people are sleeping, lowering the chance that they'll be able to get to the hospital in time for a potentially brain-saving treatment, a new study suggests.

"Because the only treatment for ischemic stroke must be given within a few hours after the first symptoms begin, people who wake up with stroke symptoms often can't receive the treatment since we can't determine when the symptoms started," Dr. Jason Mackey, of the University of Cincinnati and a study co-author, said in a news release from the American Academy of Neurology. "Imaging studies are being conducted now to help us develop better methods to identify which people are most likely to benefit from the treatment, even if symptoms started during the night."

In the study, published in the May 10 issue of Neurology, researchers examined the medical records of 1,854 adults who suffered from ischemic strokes in a one-year period and were treated at emergency rooms in the Cincinnati area. Ischemic stroke is caused by blocked blood flow in the brain, usually because of a clot.

In 14 percent of the cases, people woke up with symptoms of a stroke. Nationwide, that would account for 58,000 people who visit emergency rooms with stroke systems annually, the study authors pointed out.

Of 273 people who had so-called "wake-up strokes," at least 98 would have been eligible for treatment with a blood clot-busting drug called tPA if doctors had known when the stroke had begun, the study reported.

"If a stroke started more than a few hours ago, tPA is not indicated because it can cause bleeding that will extend and enlarge the stroke," explained Dr. Byron K. Lee, associate professor of medicine and director of the Electrophysiology Laboratories and Clinics at the University of California, San Francisco. "In wake-up strokes, it's nearly impossible to know when the symptoms started [so] tPA is not an option and, therefore, the neurologic deficits have a higher chance of becoming permanent."

If you wake up feeling strange symptoms, Lee said, don't sit around. "People should not wait for any new neurologic deficits in the morning to pass or go away as they become less groggy," he said. "They should seek medical attention immediately. Even though tPA may not be an option in wake-up strokes, there are many other treatments that can be given in an emergency room or hospital."

According to the National Stroke Association, symptoms of a stroke include:

  • Sudden paralysis or weakness in the face or limbs, especially on one side of the body
  • Sudden problems with balance or walking
  • Sudden vision problems
  • Slurred speech
  • Sudden confusion or problems speaking or understanding simple statements
  • Sudden severe headache with no apparent cause

Stroke experts offer a simple way to help people remember what to look for if they think they are witnessing a stroke: Think FAST (Face, Arms, Speech, Time):

Face: See if the person is able to smile, or if one side of their face seems to droop.

Arms: Can the person raise both arms, or does one side drift downward?

Speech: See if the person is able to speak clearly or repeat a simple phrase.

Time: Call 9-1-1 immediately if the person exhibits any of these signs.

More information

For more about the signs of stroke, visit the U.S. National Institutes of Health.

Heart Failure Patients' Osteoporosis Often Undiagnosed, Untreated

ScienceDaily

Tuesday, May 10, 2011

ScienceDaily (May 10, 2011) — One in 10 heart failure patients had compression fractures in the spine that could have been detected by a chest X-ray, but few are receiving treatment to help prevent such fractures, according to a Canadian study published in the American Heart Association journal Circulation: Heart Failure.

Among 623 heart failure patients, researchers found that 12 percent had moderate to severe vertebral compression fractures and 55 percent of those had multiple fractures. These fractures are a sign of osteoporosis, a condition in which bones become less dense and have a high risk of breaking. Only 15 percent of the heart failure patients with spinal fractures were being treated for osteoporosis, despite having a higher risk for fractures.

After adjusting for other risk factors for osteoporosis, heart failure patients who also had atrial fibrillation were twice as likely to have vertebral fractures as those with normal heart rhythms.

"Osteoporosis is an infrequently recognized and undertreated comorbidity of heart failure," said Kristin J. Lyons, M.D., C.M., lead author of the study and chief medical resident in the Department of Medicine at the University of Alberta in Edmonton, Canada. "Fortunately, the chest X-ray can be used as a case-finding tool to increase fracture identification."

Physicians' attention to the chest X-ray findings of their heart failure patients are key, said Justin A. Ezekowitz, M.D., senior author of the study and assistant professor at the Mazankowski Alberta Heart Institute in the University of Alberta in Edmonton. "While reviewing chest X-rays to look at the heart and lungs, physicians also need to look carefully at the bones. If fractures are found, patients need to be treated with dietary modification, exercise and, if indicated, osteoporosis medications. Treatment can reduce future fractures by as much as 50 percent."

Participants in the study were average age 69, 32 percent were 75 years or older and 31 percent were women. Average left ventricular ejection fraction was 32 percent in about half, 38 percent had atrial fibrillation and 65 percent had ischemic cardiomyopathy.

Heart failure patients with spinal fractures were older, more likely to be female, weighed less and more likely to have atrial fibrillation, the researchers found.

"As the population ages, two of the most prevalent diseases are heart disease and osteoporosis," Ezekowitz said. "While hip fractures are the most devastating complication of osteoporosis, vertebral compression fractures are by far the most common. Unfortunately, 60 percent to70 percent of spinal fractures are initially asymptomatic, escaping clinical detection yet placing the patients at higher risk for another vertebral facture and subsequent hip fractures."

Researchers found a higher incidence of fractures than in previous studies because many of the spinal fractures were asymptomatic and undiagnosed, he said.

In the past, treatments for osteoporosis, such as bisphosphonate drugs, have been reported to lead to atrial fibrillation; however, the Canadian researchers found no association.

The researchers hypothesize that hyperaldosteronism (high levels of the hormone aldosterone) may provide a plausible explanation for the relationship between chronic heart failure, osteoporosis and atrial fibrillation. Aldosterone, a hormone made in the adrenal gland, helps regulate blood pressure, the balance of fluids and electrolytes.

High levels of aldosterone in past studies have been shown to play a role in osteoporosis related fractures and also have led to atrial fibrillation, Ezekowitz said. "Further study is needed, but it could be that treatment with an aldosterone antagonist like spironolactone could lower the incidence of fractures and atrial fibrillation in these patients."

Further studies also are needed to either confirm or refute a link with hyperaldosteronism, Ezekowitz said.

Limitations of the study include that chest X-rays weren't performed specifically to diagnose spinal fractures and bone mineral density tests were not performed. The study's strengths were the completeness of the description of the patients and that all the chest X-rays were performed at one center where the radiologists were board certified, and the chest X-rays have been evaluated and found to be very specific for spinal fractures.

The researchers are studying whether atrial fibrillation should be considered as a risk factor for fractures in heart failure patients.

Sumit R. Majumdar, M.D., M.P.H., was also a co-author of the study. Author disclosures are on the manuscript.

Anonymous donations to the Heart Function Clinic via University Hospital Foundation in Edmonton, Canada funded the study.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

A Capsule Camera Instead of a Colonoscopy?

By Jenifer Goodwin
HealthDay Reporter

HealthDay News

Tuesday, May 10, 2011

TUESDAY, May 10 (HealthDay News) -- A new technology that uses a remote-controlled capsule camera to scan the inside of the colon may one day be an alternative to colonoscopy, a new study suggests.

Researchers from Japan's Osaka Medical College have developed a "self-propelled capsule endoscope" that can be inserted into the anus and driven through the colon via remote control and a magnetic field, capturing images along the way.

Similar capsule cameras are currently used to scout out problems in the small intestine, said Dr. Durado Brooks, director of colorectal cancer for the American Cancer Society. Patients swallow the capsule, which then moves through the digestive system much in the same way that food does, recording images of the inside of the intestine.

But capsules haven't worked as well in looking for problems in the colon, Brooks noted.

Part of the reason is that the colon has many nooks and crannies. During a colonoscopy, physicians move an endoscope, or a flexible tube containing a light and a camera, around inside the colon to get a full view, something that can't be done easily with capsule cameras.

"The colon is not a smooth tube. It's not like a pipe," Brooks said. "It's a convoluted, muscular tube with a lot of folds and crevices. The capsule camera is going to need to be able to visualize behind the folds and into the crevices."

Also, the colon -- though at about 4.5-feet long is considerably shorter than the 21-feet of the small intestine -- is larger in diameter than the small intestine, making getting a full 360 degree view more difficult.

Finally, capsule cameras currently in use take a long time to move through the digestive tract. To get a good view of the colon, it would have to be empty of waste material, including stool and mucus. Even if a patient undergoes an enema, waste material that hasn't yet made its way to the colon may end up obscuring the view by the time the capsule camera gets there.

According to the new study, Japanese researchers went in the other way, so to speak.

They first injected water into the anus, and then inserted the pill camera. Controlling the device by remote control, they obtained images using a real-time monitoring system.

The capsule moved smoothly through the colon and could be removed from the anus easily and safely, according to the study.

"This trial demonstrates the feasibility to control and maneuver the capsule in the colon of a human who is awake," study author Dr. Takanori Kuramoto, said in a Digestive Disease Week news release. "Our study is the first trial of an actively propelled video capsule in the human colon, and we expect it will lead to the development of a commercial system to propel the capsule in a way that lets doctors visualize the entire gastrointestinal tract from esophagus to anus."

The findings were presented Sunday at Digestive Disease Week in Chicago.

Brooks called the findings a "proof of principle," meaning that researchers have shown using camera capsules to scan the colon is possible. But far more research needs to be done before the devices should actually be put to use, including determining that they work as well as current screening, such as colonoscopy.

"The next step is determining whether or not it can give an accurate assessment of what is going on in the colon," Brooks said.

Even if it can, capsule camera will never replace colonoscopies, he said. When physicians detect abnormalities such as polyps that can develop into cancer during a colonoscopy, they'll often remove the polyps right then and there.

If a capsule detects polyps, the patient is going to have to undergo a colonoscopy afterward to get the polyps treated and biopsied.

"You can't do that through a capsule," he said.

Dr. Joel Brill, chief medical officer for the American Gastroenterological Association's Digestive Health Outcomes Registry, said any device that has the potential to make colorectal cancer screening more tolerable is a positive development.

"This looks like it's a feasibility study," Brill said. "As the researchers have said, the next step is to see if this can actually be commercialized or be done outside of a research setting."

More information

The American Cancer Society has more on colorectal cancer.

Beneficial Bacteria Help Repair Intestinal Injury by Inducing Reactive Oxygen Species

ScienceDaily

Tuesday, May 10, 2011

ScienceDaily (May 10, 2011) — The gut may need bacteria to provide a little bit of oxidative stress to stay healthy, new research suggests.

Probiotic bacteria promote healing of the intestinal lining in mice by inducing the production of reactive oxygen species, researchers at Emory University School of Medicine have shown.

The results, published online this week in Proceedings of the National Academy of Sciences Early Edition, demonstrate a mechanism by which bacterial cultures in foods such as yogurt and kimchi have beneficial effects on intestinal health. The insights gained could also guide doctors to improved treatments for intestinal diseases, such as necrotizing enterocolitis in premature babies or intestinal injury in critically ill adults.

The laboratories of Andrew Neish, MD and Asma Nusrat, MD, both professors of pathology and laboratory medicine, teamed up for the study. The paper's co-first authors are postdoctoral fellow Philip Swanson, PhD and associate research professor Amrita Kumar, PhD.

"It's been known for years that probiotic bacteria can have these kinds of helpful effects, but it wasn't really clear how this worked," Neish says. "We've identified one example, among many, of how certain kinds of bacteria have specific biochemical functions in the body."

Recent research has shown that the bacteria in our intestines influence our metabolism and immune systems. For example, an imbalance in the proportions of harmful and beneficial bacteria seems to over-activate immune cells in the intestines, driving inflammatory bowel disease.

Intestinal epithelial cells, the cells that line the intestine, live in close contact with bacteria and normally form a barrier that keeps bacteria away from other organs. They can repair small gaps in the barrier, which breaks down in intestinal diseases, by migrating into the gaps.

The researchers showed that Lactobacillus rhamnosus bacteria can accelerate this healing process, both in culture dishes and in mice with intestines damaged by chemicals. Lactobacillus rhamnosus, a species of bacteria found naturally in human intestines and often used as a probiotic, is a relative of other kinds of Lactobacillus bacteria found in fermented foods.

"Unlike most cell types that can not tolerate bacterial contact, intestinal epithelial cells respond to Lactobacillus rhamnosus by increasing their motility," Neish says.

Using a fluorescent dye that is sensitive to reactive oxygen species (ROS), the researchers showed that intestinal epithelial cells produce ROS internally when in contact with Lactobacillus rhamnosus. The ROS induced by the bacteria stimulate the formation of focal adhesions, structures on intestinal epithelial cells that act as anchors for their movement.

"Focal adhesions are where cells attach to the matrix that surrounds them," Neish says. "The cells lay them down on one side and remove them on the other side, like the tracks of a bulldozer."

In studying the effect of Lactobacillus rhamnosus on intestines in mice, Neish's team focused on the small intestine, which normally has fewer bacteria than the colon. This allowed them to avoid using antibiotics to remove naturally existing bacteria beforehand, and to see ROS production in tissue from live animals.

Antioxidants that mop up ROS prevent the bacteria from promoting wound healing in the laboratory, the researchers showed. Neish says his team's finding suggests that large amounts of antioxidants by humans could interfere with the ability of bacteria to promote intestinal healing.

Previously, it was known that immune cells respond to bacteria by producing ROS, but Neish and his colleagues believe the ROS production they observed stimulates tissue maintenance and is a marker of cohabitation and adaptation, rather than defense.

Oxidative stress, or an imbalance of reactive oxygen species throughout the body, has been linked to diseases such as heart disease and stroke. However, scientists have learned in recent years that cells can also use reactive oxygen species in a controlled, local way to send signals needed for normal functions.

Neish says his team is working to determine which part of the bacteria is responsible for inducing cells to produce ROS. Once identified, this component could be used to encourage intestinal healing in situations where contact with large amounts of live bacteria might be dangerous, such as in premature babies or critically ill adults.

The research was supported by the National Institutes of Health.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

P. A. Swanson, A. Kumar, S. Samarin, M. Vijay-Kumar, K. Kundu, N. Murthy, J. Hansen, A. Nusrat, A. S. Neish. Enteric commensal bacteria potentiate epithelial restitution via reactive oxygen species-mediated inactivation of focal adhesion kinase phosphatases. Proceedings of the National Academy of Sciences, 2011; DOI: 10.1073/pnas.1010042108

Colonoscopy Better Than Alternative at Spotting Cancer in Seniors: Study

By Randy Dotinga
HealthDay Reporter

HealthDay News

Tuesday, May 10, 2011

TUESDAY, May 10 (HealthDay News) -- Colonoscopy is significantly better than the less expensive screening procedure called sigmoidoscopy at detecting colon cancer in older patients, a new study says.

"We imagined there would be some difference, but there's a four-fold difference" between the two screening tests when it comes to detecting cancer, said study lead author Dr. Yize Richard Wang, a fellow at the Mayo Clinic in Jacksonville, Fla.

"Colonoscopy still remains the gold standard," added Wang, a health economist.

In the United States, colon cancer kills more than 51,000 people a year, according to the National Cancer Institute. Screening helps identify cancer before symptoms appear, when it may be easier to treat.

Colonoscopy, the most common screening test for colon cancer, involves threading a scope with a tiny camera through the length of the colon. But patients can also choose flexible sigmoidoscopy, which uses a shorter scope, costs less and may be more comfortable. However, sigmoidoscopy examines only half or less of the colon, Wang said.

Years ago sigmoidoscopy was the main screening test for colon cancer, but it has become less common over time. However, "from a patient perspective, the preparation and discomfort associated with a sigmoidoscopy is often considered less burdensome," said Dr. Thomas Semrad, assistant professor of internal medicine at the University of California, Davis Medical Center, who's familiar with the study findings.

Using a national database, the study authors examined the records of 52,236 patients 67 or older who underwent colonoscopy or sigmoidoscopy between 1998 and 2005 and were diagnosed with colon cancer within three years of the procedure. According to the study abstract, 57,412 colonoscopies were performed, as were 3,523 sigmoidoscopies.

The percentage of new or missed left-sided colon cancers was 12 percent among the sigmoidoscopy patients but only 4 percent for the colonoscopy patients.

It's not clear why colonoscopy was better at detecting cancers, Wang said, but it may be because the sigmoidoscopy misses part of the colon.

"If you suspect the patient has colon cancer, colonoscopy is still a better test than flexible sigmoidoscopy," he said.

Differences in bowel preparation and lack of sedation might also help explain the variation, the study authors said, noting further research is necessary.

The study was to be presented Tuesday at the Digestive Diseases Week conference in Chicago. The research is considered preliminary because it has not been subject to the scrutiny required for publication in a peer-reviewed journal.

Although the study did not include people younger than 67, "the results might be similar," Wang said.

Semrad said sigmoidoscopy may be appropriate in some cases. Compared to a colonoscopy, "an individual sigmoidoscopy will cost less, be easier to perform, and in the right hands can be an appropriate screening test," he said.

"Ultimately, the right test will be different for different patients and different health systems," Semrad added.

The U.S. Preventive Services Task Force recommends colonoscopy screening every 10 years for people 50 to 75 years old who are considered at average risk of getting colon cancer.

It's important that people undergo screening, Semrad said. "We know that we could save thousands of lives each year if everyone was screened according to the guidelines," he added.

But some people have a fear of the procedure, he noted. "Because the preparation is easier and the discomfort is often less, [sigmoidoscopy] can be especially important testing for patients unwilling to undergo colonoscopy," he noted.

More information

For more about colon cancer, visit the U.S. National Library of Medicine.

Depression Associated With Poor Medication Adherence in Patients With Chronic Illnesses

ScienceDaily

Tuesday, May 10, 2011

ScienceDaily (May 10, 2011) — People who are depressed are less likely to adhere to medications for their chronic health problems than patients who are not depressed, putting them at increased risk of poor health, according to a new RAND Corporation study.

Researchers found that depressed patients across a wide array of chronic illnesses such as diabetes and heart disease had 76 percent greater odds of being non-adherent with their medications compared to patients who were not depressed. The findings were published online by the Journal of General Internal Medicine.

The study is the largest systematic review to date to look at the role that depression plays in medication adherence among patients in the United States.

"These findings provide the best evidence to date that depression is an important risk factor that may influence whether patients adhere to their medications," said Dr. Walid F. Gellad, the study's senior author and a natural scientist at RAND, a nonprofit research organization. "There are important implications for both patient health and for health care costs.

"Doctors and other providers should periodically ask patients with depression about medication adherence. Also, when treating a patient who is not taking their medication correctly, they should consider the possibility that depression is contributing to the problem."

Poor adherence to prescribed medication is a well-known problem that is associated with higher death rates among people with chronic illnesses. It is also blamed for increasing U.S. health care costs.

Researchers from RAND and the Claremont Graduate School conducted the study by examining past studies that have measured medication adherence. They combined information from 31 studies involving more than 18,000 people -- significantly more than past reviews -to examine the link between medication adherence and depression.

The study is the first to review the association between depression and medication adherence for patients with high blood pressure and high cholesterol. Other conditions examined in the study include coronary heart disease, diabetes and asthma. The link between depression and medication adherence did not vary significantly between the different chronic illnesses, said Gellad, who is also a physician with the VA Pittsburgh Healthcare System.

"The consistent link between depression and nonadherence across all these illnesses underscores the seriousness of the role that depression plays in keeping people from properly managing chronic conditions," said Jerry L. Grenard, the study's lead author and an assistant professor at the Claremont Graduate School. "That consistency also suggests that lessons learned about how to improve medication adherence among depressed patients with one disease may be applied to other chronic conditions."

Researchers say that depression is just one barrier to getting patients to follow medication recommendations. Additional well-documented barriers to medication adherence are dose complexity and patient cost-sharing. Other barriers that may play a role include beliefs about medications, social support, side effects and provider factors.

The study was supported by the Agency for Healthcare Research and Quality and by Mehlman Vogel Castagnetti.

Other authors of the study are Brett A. Munjas, John L. Adams, Marika Suttorp and Margaret Maglione of RAND, and Elizabeth A. McGlynn of Kaiser Permanente.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Jerry L. Grenard, Brett A. Munjas, John L. Adams, Marika Suttorp, Margaret Maglione, Elizabeth A. McGlynn, Walid F. Gellad. Depression and Medication Adherence in the Treatment of Chronic Diseases in the United States: A Meta-Analysis. Journal of General Internal Medicine, 2011; DOI: 10.1007/s11606-011-1704-y

Are Coffee Drinkers Less Prone to Aggressive Breast Cancer?

By Alan Mozes
HealthDay Reporter

HealthDay News

Tuesday, May 10, 2011

TUESDAY, May 10 (HealthDay News) -- Women who drink a substantial amount of coffee each day may lower their risk for developing a particular type of breast cancer, Swedish researchers say.

Their study linked consumption of five or more cups of coffee a day to a relatively marked reduction in the non-hormone-responsive disease known as ER-negative breast cancer. However, coffee consumption did not appear to lower the risk for developing ER-positive breast cancer, a hormone-responsive estrogen receptor form of the disease.

Daily consumption of coffee may protect against the most aggressive type of breast cancer, ER-negative, said study co-author Dr. Per Hal, a professor in the medical epidemiology and biostatistics department at the Karolinska Institute in Stockholm.

"Now, we don't have all the details," he cautioned. "We don't know, for example, what specific type of coffee we're talking about here. But what we do know is that the protective effect is quite striking and remains even after adjusting for a lot of other factors that have the potential to play a protective role. And we know that we're talking about what we could call a relatively normal amount of coffee drinking. Certainly we're not talking about consuming gigantic amounts of coffee. So, this is a very intriguing finding."

The study, reported online May 11 in Breast Cancer Research, involved 5,929 Swedish women, aged 50 to 74. About half of the women had breast cancer.

Questionnaires were used to assess behavioral and health characteristics, including smoking and drinking patterns, physical activity routines, family history of breast cancer, hormone therapy protocols, nutritional intake, body mass index, education level and coffee consumption habits. Both tumor status and breast cancer type were also noted.

The principle finding: Drinking coffee appeared to spur a "strong reduction" in risk for ER-negative breast cancer, the researchers wrote. Women who drank five cups of coffee a day had a 33 percent to 57 percent lower risk for ER-negative cancer than did those who drank less than one cup a day.

The study revealed an apparent association between coffee consumption and a reduction in breast cancer risk, but not a cause-and-effect relationship.

And Hal was not eager for consumers to jump to conclusions.

"There are one or two other studies that have pointed in the same direction as ours -- but not many, just a few," he cautioned. "So before I would go to tell my neighbors to start drinking more coffee than they already do, I would like to know what is the biological mechanism at work here. And that's not yet clear."

Hal noted that he and his colleagues are now working on a new study to tease out that information.

Dr. Stephanie Bernik, chief of surgical oncology at Lenox Hill Hospital in New York City, described the findings as both "interesting" and "provocative," given that the kind of cancer coffee appears to protect against is one for which there are relatively few effective treatments.

"It is this kind of study that opens the door to improving treatment, as scientists try to uncover what biologic factors in a substance are beneficial, and then attempt to extract these factors and use them to defend against cancers," Bernik noted. "The goal would be to try and discover what it is in coffee that may be beneficial."

"The next step is to find out what chemical factors in coffee cause the decreased rate of cancer and then attempt to see if these same chemicals can be used to treat a patient once they are already diagnosed with cancer," she said.

More information

The U.S. National Cancer Institute has more about breast cancer.

Mitochondria: Body’s Power Stations Can Affect Aging

ScienceDaily

Tuesday, May 10, 2011

ScienceDaily (May 10, 2011) — Mitochondria are the body's energy producers, the power stations inside our cells. Researchers at the University of Gothenburg, Sweden, have now identified a group of mitochondrial proteins, the absence of which allows other protein groups to stabilise the genome. This could delay the onset of age-related diseases and increase lifespan.

Some theories of human aging suggest that the power generators of the cell, the mitochondria, play a part in the process. In addition to supplying us with energy in a usable form, mitochondria also produce harmful by-products -- reactive oxyradicals that attack and damage various cell components. Eventually these injuries become too much for the cell to cope with, and it loses its capacity to maintain important functions, so the organism starts to age. That's the theory anyway. Oddly enough, several studies have shown that certain mitochondrial dysfunctions can actually delay aging, at least in fungi, worms and flies. The underlying mechanisms have yet to be determined.

In a study from the Department of Cell and Molecular Biology at the University of Gothenburg, published in the journal Molecular Cell, a research team has now identified a group of mitochondrial proteins that are involved in this type of aging regulation. The researchers found that a group of proteins called MTC proteins, which are normally needed for mitochondrial protein synthesis, also have other functions that influence genome stability and the cell's capacity to remove damaged and harmful proteins.

"When a certain MTC protein is lacking in the cell, e.g. because of a mutation in the corresponding gene, the other MTC proteins appear to adopt a new function. They then gain increased significance for the stabilisation of the genome and for combating protein damage, which leads to increased lifespan," says Thomas Nystr๖m of the Department of Cell and Molecular Biology.

He adds, "These studies also show that this MTC-dependent regulation of the rate of aging uses the same signaling pathways that are activated in calorie restriction -- something that extends the lifespan of many different organisms, including yeasts, mice and primates. Some of the MTC proteins identified in this study can also be found in the human cell, raising the obvious question of whether they play a similar role in the regulation of our own aging processes. It is possible that modulating the activity of the MTC proteins could enable us to improve the capacity of the cell to delay the onset of age-related diseases. These include diseases related to instability of the genome, such as cancer, as well as those related to harmful proteins, such as Alzheimer's disease and Parkinson's disease. At the moment this is only speculation, and the precise mechanism underlying the role of the MTC proteins in the aging process is a fascinating question that remains to be answered."

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Antonio Caballero, Ana Ugidos, Beidong Liu, David ึling, Kristian Kvint, Xinxin Hao, Cora Mignat, Laurence Nachin, Mikael Molin, Thomas Nystr๖m. Absence of Mitochondrial Translation Control Proteins Extends Life Span by Activating Sirtuin-Dependent Silencing. Molecular Cell, 2011; 42 (3): 390 DOI: 10.1016/j.molcel.2011.03.021

Mental Decline Common in Women Over 85: Study

HealthDay News

Tuesday, May 10, 2011

TUESDAY, May 10 (HealthDay News) -- Mild problems with thinking and memory, as well as full-blown dementia, are common in the "oldest old" women, a new study finds.

The oldest old refers to people age 85 and older -- the fastest-growing segment of the U.S. population. Their numbers are expected to increase by 40 percent during the next decade, according to background information in the study.

"The 'oldest old,' defined as people 85 years or older, is the fastest growing segment of the United States' population. The nature and prevalence of cognitive impairment in this group has not been fully determined," noted Dr. Marc L. Gordon, a neurologist and Alzheimer's researcher at The Feinstein Institute for Medical Research in Manhasset, N.Y. He was not involved in the new research.

In the study, researchers at the University of California, San Francisco, analyzed data on nearly 1,300 women averaging just over 88 years of age who were enrolled in the Women Cognitive Impairment Study of Exceptional Aging. Of those women, 231 (17.8 percent) had been diagnosed with dementia and 301 (about 23 percent) had been diagnosed with "mild cognitive impairment."

Women aged 90 or older were more likely to have mild cognitive impairment than those aged 85 to 89 (24.5 percent vs. 22.7 percent), said Dr. Kristine Yaffe and colleagues at UCSF.

They also found that prevalence of dementia in women aged 90 or older was nearly double that of those aged 85 to 89 -- 28.2 percent vs. about 14 percent.

On average, women with dementia were older, less likely to have completed high school, more likely to live in a nursing home, and more likely to have a history of depression and stroke.

Gordon stressed that even this study might not have captured the true range of mental impairment in elderly women.

"Because women who develop cognitive impairment may be more likely to drop out of the study, the actual prevalence may be even higher than estimated on the basis of this study," he explained. "Nonetheless, the authors have established that the prevalence of dementia continues to increase with advancing age, while the subtypes of dementia and MCI are similar to 'younger old' populations. They underscore the importance of screening for cognitive disorders in the oldest old."

The study appears in the May issue of the Archives of Neurology.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about dementia.

Monday, May 9, 2011 

Heart Medication Best at Bedtime, Animal Study Suggests

ScienceDaily

Monday, May 9, 2011

ScienceDaily (May 9, 2011) — When doctors give heart drugs to patients, the time of day can make a big difference, according to new research by University of Guelph scientists.

Many doctors prefer to give heart drugs to patients in the morning. But the study revealed that angiotensin-converting enzyme (ACE) inhibitors -- commonly given to patients with high blood pressure or after a heart attack or during heart failure -- improve heart structure and function when given at sleep time. In fact, when administered during wake time, ACE inhibitors are no more effective than a placebo, the study found.

The research was conducted on mice with high blood pressure.

Guelph professors Tami Martino, Department of Biomedical Sciences, Jeremy Simpson, Department of Human Health and Nutritional Sciences and Nazneen Tata conducted the study in the laboratory of Dr. Michael Sole at the Peter Munk Cardiac Centre and the Heart and Stroke Richard Lewar Centre of Excellence in Toronto.

The study will appear May 17 in the Journal of the American College of Cardiology.

"Heart drugs are often given to patients in the morning for convenience without considering biological rhythms or time-related risks of adverse effects," said Martino. "But if they're given at bedtime, it's better."

That is because the drug affects a natural hormone involved in heart remodeling. Hormone levels increase at night and cause the heart to enlarge, which damages the organ in cardiac patients, said Martino.

"The sleep-time benefit of giving the ACE inhibitor correlates with the biological rhythm of this hormone," she said. "By targeting those hormones when they're highest during sleep, you're dropping their levels so they're not doing so much damage."

It's known that heart attacks and sudden cardiac death peak in early morning and night-shift workers with disturbed circadian rhythms have higher risk of heart disease and worse outcomes, said Sole, who is a cardiologist at the Toronto General Hospital.

"Earlier studies our group has worked on suggest that the heart repairs and renews itself during sleeping hours," he added.

These findings led the researchers to explore whether the effectiveness of ACE inhibitors is impacted by the time of day it's administered. The team used a short-acting version of the drug and studied the effects during wake and sleep time in a mouse model designed with high blood pressure.

Besides administering the drug to patients before bed, study results also suggest doctors should consider using a short-acting version of the drug, said Martino.

"Since the drug is most effective during sleep hours, it's not necessary to have its effects last throughout the span of an entire day. Using a short-acting version of the drug may help to reduce side effects."

Other researchers have also looked at using biological rhythms for drug treatment of other diseases, such as insulin release in diabetes and chemotherapy for cancer patients, she added.

"We are now starting to learn that biological and physiological rhythms play an important role in health and disease."

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

Martino, Tami A., Tata, Nazneen, Simpson, Jeremy A., Vanderlaan, Rachel, Dawood, Fayez, Kabir, M. Golam, Khaper, Neelam, Cifelli, Carlo, Podobed, Peter, Liu, Peter P., Husain, Mansoor, Heximer, Scott, Backx, Peter H., Sole, Michael J. The Primary Benefits of Angiotensin-Converting Enzyme Inhibition on Cardiac Remodeling Occur During Sleep Time in Murine Pressure Overload Hypertrophy. J Am Coll Cardiol, 2011 57: 2020-2028 DOI: 10.1016/j.jacc.2010.11.022

Acetaminophen tied to blood cancers

By Frederik Joelving

Reuters Health

Monday, May 9, 2011

NEW YORK (Reuters Health) – New research shows chronic users of acetaminophen, a top-selling painkiller known as Tylenol in the U.S. and paracetamol in Europe, are at slightly increased risk for blood cancers.

Yet the risk remains low, and it's still uncertain what role the drug plays.

The finding adds another twist to the complicated evidence linking cancer and painkillers, and hints acetaminophen might be different from the rest.

Earlier work has shown that aspirin use might lower the odds of dying from colon cancer but increase the risk of bleeding ulcers. The picture has been less clear for blood, or hematologic, cancers, however.

"Prior to this study there was very little evidence that aspirin reduces your risk of hematological cancers," said Emily White of the Fred Hutchinson Cancer Research Center in Seattle, who worked on the new research.

There were some suggestions that acetaminophen might increase the risk of the cancers, on the other hand, but those were based on individual cases of blood cancer.

Studies of individual patients aren't considered as strong as the new one, which tracked a large population of healthy people over time.

"We have the first prospective study," White told Reuters Health.

Still, she warned, there is no proof that acetaminophen causes cancer, and the new results need to be confirmed before they are used in any treatment decision.

Earlier work has linked acetaminophen to asthma and eczema as well, but scientists still don't agree on whether the drug is the actual culprit or just an innocent bystander.

The new study suffers from the same limitations, in that people who use lots of painkillers could be dealing with medical problems that set them up for cancer down the road.

The scientists followed nearly 65,000 older men and women in Washington State. At the outset, they asked the participants about their use of painkillers over the past ten years and made sure that no one had cancer (except skin cancer).

Over some six years on average, 577 people -- or less than one percent -- developed a cancer involving the blood cells. Examples of such cancers include lymphoma and myelodysplastic syndrome, or MDS.

More than nine percent of people who developed one of these cancers used high amounts of acetaminophen, compared to only five percent of those who didn't get sick.

After accounting for things like age, arthritis and a family history of certain blood cancers, chronic acetaminophen users had nearly twice the risk of developing the disease.

"A person who is age 50 or older has about a one-percent risk in ten years of getting one of these cancers," White said. "Our study suggests that if you use acetaminophen at least four times a week for at least four years, that would increase the risk to about two percent."

No other painkillers -- including aspirin and ibuprofen -- were tied to the risk of blood cancers.

Dr. Raymond DuBois, a cancer prevention expert at the University of Texas MD Anderson Cancer Center in Houston, said acetaminophen works very differently than other painkillers and so might be expected to have different effects on cancer.

Still, "It was quite surprising to see that acetaminophen use increased the risk of" blood cancers, DuBois, who was not involved in the study, told Reuters Health by email.

McNeil Consumer Healthcare, the Johnson & Johnson subsidiary that sells Tylenol, did not respond to requests for comment.

White said it is too soon to make any recommendations based on the new study, and that none of the painkillers is free of side effects.

"Long-term use of any over the counter drug might have adverse effects," she said. "You have to weigh the benefits against the risk of all the drugs."

Source: http://bit.ly/l8aYI0

Journal of Clinical Oncology, May 9, 2011.

Lifestyle, diet have little effect on Alzhiemer's

By Julie Steenhuysen

Reuters

Monday, May 9, 2011

CHICAGO (Reuters) – There is no strong evidence that any dietary or lifestyle changes can reduce a person's risk of developing Alzheimer's disease, a U.S. government panel said on Monday.

Experts called together by the National Institutes of Health examined scores of studies about whether diet, exercise, nutritional supplements and chronic diseases like diabetes or hypertension affect a person's risk of getting the fatal, brain-wasting disease.

They found some signs that diabetes, high cholesterol and smoking could raise the risk of Alzheimer's.

And they found that eating a Mediterranean-type diet -- high in healthy fats, fruits and vegetables -- and taking folic acid, cutting back on alcohol and keeping the brain and body fit appear to lower the risk.

But in every case, the evidence was not strong enough to say for sure, the panel found.

"Although numerous studies have investigated risk factors and potential therapies for Alzheimer's disease, significant gaps in scientific knowledge exist," Dr. Martha Daviglus of Northwestern University Feinberg School of Medicine, Chicago, and colleagues wrote in the Archives of Neurology.

"Currently, firm conclusions simply cannot be drawn about the association of any modifiable risk factor with Alzheimer's disease, and there is insufficient evidence to support the use of any lifestyle interventions or dietary supplements to prevent Alzheimer's," the panel wrote.

Old age remains the most reliable known risk factor for the disease, which afflicts 26 million people worldwide.

People with a specific variant of the apolipoprotein E or APOE gene are also at greater risk.

The U.S. panel called for large-scale, long-term, population-based studies and clinical trials to evaluate what, if anything, can be done to slow or stop its progression.

In the meantime, the experts said older people and those with Alzheimer's in their family should keep active and do all they can to maintain good health.

"Until more conclusive results are available, individuals should continue to aim for a physically and mentally active and healthy lifestyle and prevention of the well-known major risk factors for chronic diseases," they wrote.

The Alzheimer's Association said significant increases in federal funding for disease research were needed to conduct the studies called for in the NIH panel's report.

"It is clear that there is a relationship between heart health and brain health, and this relationship needs further research so that we can make definitive recommendations," the group said in a statement.

"Nonetheless, even now with the preliminary evidence that we have, this connection is another good reason to live a healthy lifestyle that is beneficial for your heart health such as controlling your cardiovascular risk factors -- your blood pressure, blood sugar, and body weight."

Policy-makers and drug companies are working furiously to find ways to prevent Alzheimer's as the Baby Boom generation heads into old age.

Of the 5.4 million Americans with the disease, an estimated 4 percent are under 65, 6 percent are 65 to 74, 45 percent are 75 to 84, and 45 percent are 85 or older.

(Editing by Laura MacInnis)

Acetaminophen tied to blood cancers

By Frederik Joelving

Reuters Health

Monday, May 9, 2011

NEW YORK (Reuters Health) – New research shows chronic users of acetaminophen, a top-selling painkiller known as Tylenol in the U.S. and paracetamol in Europe, are at slightly increased risk for blood cancers.

Yet the risk remains low, and it's still uncertain what role the drug plays.

The finding adds another twist to the complicated evidence linking cancer and painkillers, and hints acetaminophen might be different from the rest.

Earlier work has shown that aspirin use might lower the odds of dying from colon cancer but increase the risk of bleeding ulcers. The picture has been less clear for blood, or hematologic, cancers, however.

"Prior to this study there was very little evidence that aspirin reduces your risk of hematological cancers," said Emily White of the Fred Hutchinson Cancer Research Center in Seattle, who worked on the new research.

There were some suggestions that acetaminophen might increase the risk of the cancers, on the other hand, but those were based on individual cases of blood cancer.

Studies of individual patients aren't considered as strong as the new one, which tracked a large population of healthy people over time.

"We have the first prospective study," White told Reuters Health.

Still, she warned, there is no proof that acetaminophen causes cancer, and the new results need to be confirmed before they are used in any treatment decision.

Earlier work has linked acetaminophen to asthma and eczema as well, but scientists still don't agree on whether the drug is the actual culprit or just an innocent bystander.

The new study suffers from the same limitations, in that people who use lots of painkillers could be dealing with medical problems that set them up for cancer down the road.

The scientists followed nearly 65,000 older men and women in Washington State. At the outset, they asked the participants about their use of painkillers over the past ten years and made sure that no one had cancer (except skin cancer).

Over some six years on average, 577 people -- or less than one percent -- developed a cancer involving the blood cells. Examples of such cancers include lymphoma and myelodysplastic syndrome, or MDS.

More than nine percent of people who developed one of these cancers used high amounts of acetaminophen, compared to only five percent of those who didn't get sick.

After accounting for things like age, arthritis and a family history of certain blood cancers, chronic acetaminophen users had nearly twice the risk of developing the disease.

"A person who is age 50 or older has about a one-percent risk in ten years of getting one of these cancers," White said. "Our study suggests that if you use acetaminophen at least four times a week for at least four years, that would increase the risk to about two percent."

No other painkillers -- including aspirin and ibuprofen -- were tied to the risk of blood cancers.

Dr. Raymond DuBois, a cancer prevention expert at the University of Texas MD Anderson Cancer Center in Houston, said acetaminophen works very differently than other painkillers and so might be expected to have different effects on cancer.

Still, "It was quite surprising to see that acetaminophen use increased the risk of" blood cancers, DuBois, who was not involved in the study, told Reuters Health by email.

McNeil Consumer Healthcare, the Johnson & Johnson subsidiary that sells Tylenol, did not respond to requests for comment.

White said it is too soon to make any recommendations based on the new study, and that none of the painkillers is free of side effects.

"Long-term use of any over the counter drug might have adverse effects," she said. "You have to weigh the benefits against the risk of all the drugs."

Source: http://bit.ly/l8aYI0

Journal of Clinical Oncology, May 9, 2011.

Fewer behavior problems for breastfed kids: study

By Kate Kelland

Reuters

Monday, May 9, 2011

LONDON (Reuters) – Babies who are breastfed are less likely to grow into children with behavior problems by the time they reach the age of five than those who receive formula milk, scientists said on Tuesday.

In a study in the Archives of Disease in Childhood journal, British researchers used a "strengths and difficulties" questionnaire completed by parents about their children and found that abnormal scores were less common in children who were breastfed for at least four months.

Maria Quigley of the national perinatal epidemiology unit at Oxford University, who led the work, said the findings "provide even more evidence for the benefits of breastfeeding."

"Mothers who want to breastfeed should be given all the support they need. Many women struggle to breastfeed for as long as they might otherwise like, and many don't receive the support that might make a difference," she said in a statement.

Some benefits of breastfeeding are already well known -- for example breastfed babies have lower rates of infections, and mothers who breastfeed have a reduced risk of breast cancer.

A range of other health and child development benefits have also been suggested -- such as fewer behavioral problems and lower levels of obesity -- but the British team said evidence for these has been inconsistent across different studies.

In this study researchers from the universities of Oxford, Essex, York and from University College London used a nationwide British survey of babies born in 2000-2001 called the Millennium Cohort Study and included data for more than 9,500 mothers and babies born at full term to families of white ethnic background.

They used data on whether mothers had breastfed and how long for and combined these with the results of the "strengths and difficulties" questionnaire used for identifying children with possible behavioral problems.

They found abnormal scores for the questionnaires, which indicate potential behavioral problems, were less common in children breastfed for at least four months -- at 6 percent --than in formula fed children -- at 16 percent.

The lower risk of a full-term breastfed child having abnormal scores for behavior was also evident even when the researchers took into account other important influences such as socio-economic or parental factors.

"We're not necessarily talking about tearaway, unmanageable five-year-old kids," said Quigley. "It might be unusual anxiousness, restlessness, inability to socialize with other children or play fully in groups."

The researchers said one possible reason for the findings was that breast milk contains large amounts of essential long chain polyunsaturated fatty acids, growth factors and hormones which are important in brain and nervous system development.

The results might also be explained by the fact that breastfeeding leads to more interaction between mother and child and better learning of acceptable behaviors, they said.

Peter Kinderman, a professor of clinical psychology at the University of Liverpool, who was not involved in the study, said it was a good piece of research with important findings.

"Positive bonding between parent and child is known to be fantastically helpful for development," he said. "This is more evidence of the importance of breastfeeding and mother-baby attachment, not just for physical health but also for the psychological development of the child."

(Editing by Paul Casciato)

Newborn vitamin D levels tied to infection risk

By Amy Norton

Reuters Health

Monday, May 9, 2011

NEW YORK (Reuters Health) – Newborns with low vitamin D levels may have a heightened risk of developing a certain type of lung infection before their first birthday, a new study suggests.

The infection is caused by a bug known as respiratory syncytial virus (RSV). RSV can cause the small airways in the lungs to become inflamed, in a condition called bronchiolitis; it can also cause pneumonia. In fact, RSV is the most common cause of pneumonia and bronchiolitis in infants, according to the U.S. Centers for Disease Control and Prevention.

Researchers found that infants with inadequate vitamin D levels at birth were about six times more likely than others to develop RSV bronchiolitis in their first year of life.

The findings, the researchers say, raise the possibility that getting enough vitamin D during pregnancy could prevent some RSV infections.

However, studies to test that idea are still needed. In the meantime, it's just a theory.

The study's senior researcher, Dr. Louis Bont of Wilhelmina Children's Hospital in Utrecht, the Netherlands, told Reuters Health in an email that for now, pregnant women should stick with experts' general recommendations on vitamin D intake. In the U.S., the Institute of Medicine recently bumped up the recommended dose to 600 IU per day, and set an upper limit of 4,000 IU per day.

Nearly all children become infected with RSV by the time they are 2, and most have mild symptoms. But for every 10 kids, about 1 or 2 develop bronchiolitis - and about 1 in 10 of those end up in the hospital, Bont said.

The current study, scheduled for publication today in the journal Pediatrics, focused on more-serious cases of RSV where infants developed symptoms of bronchiolitis, including wheezing and a moderate to severe cough.

At the start of the study, Bont's team measured vitamin D levels in umbilical-cord blood from 156 newborns.

Overall, 27 percent had vitamin D levels that are generally considered inadequate. Another 27 percent had mid-range levels which some experts consider too low - although there's some controversy over their definition. The rest of the newborns -- 46 percent -- had adequate vitamin D levels.

Overall, 18 infants had a confirmed RSV infection during their first year of life.

The researchers found that babies with vitamin D levels in the lowest range at birth were about six times more likely to develop an RSV infection than those with adequate levels.

There was no increased risk among babies with vitamin D levels in the controversial mid-range levels.

However, the findings do not prove that higher vitamin D at birth, per se, prevents RSV infections. Instead, there could be other explanations for the link, according to Bont.

One possibility is that newborns from low-income families could be more likely to have inadequate vitamin D levels. And infants from those families may, for some yet-unknown reason, have a higher risk of severe RSV infection, Bont said.

He also noted that pregnant women with high vitamin D levels may spend more time outdoors; the body naturally synthesizes vitamin D when the skin is exposed to the sun. And those women may be more physically active or have generally healthier lifestyles.

On the other hand, vitamin D is believed to affect immune system function and inflammation. So it's plausible that the vitamin could play a role in the risk of RSV illness.

A researcher not involved in the study said that he thinks that vitamin D may indeed have a "real" effect on infants' respiratory infections. "But we have to do clinical trials," said Dr. Carlos Camargo, an associate professor of medicine at Harvard Medical School in Boston.

In a study recently published in Pediatrics, Camargo and his colleagues found that higher newborn vitamin D levels were linked to a lower risk of respiratory infections, in general, during the first three months of life.

So the current findings are "very consistent" with that study, Camargo told Reuters Health.

He and his colleagues have begun to study different doses of vitamin D for mothers during pregnancy, and vitamin D supplements for infants, to see whether they have an effect on respiratory infections.

But, Camargo said, there are already reasons for pregnant women to make sure they are getting enough vitamin D -- including their own bone health.

He suggested that women who might not have enough vitamin D in their blood -- such as those who are obese, have dark skin or get little sun -- might want to talk with their doctors about whether they should have their blood levels of the vitamin measured.

"It's possible that if you start super-low, you'll need more (supplemental vitamin D)," Camargo said.

The prenatal vitamins recommended for pregnant women contain vitamin D. Food sources include fortified cereals, milk and orange juice, and fatty fish like salmon and tuna (although pregnant women should limit themselves to two serving per week because the fish can contain traces of mercury).

Source: http://bit.ly/lnUeqg

Pediatrics, online May 9, 2011.

Burning the Midnight Oil May Lead to Weight Gain

HealthDay News

Monday, May 9, 2011

MONDAY, May 9 (HealthDay News) -- Night owls who consistently stay up late may be putting themselves at higher odds for weight gain, a new study finds.

Researchers at Northwestern University in Chicago found that people who burn the midnight oil typically consume more calories in the evening and eat more fast food than "early to bed, early to rise" types.

The study, published online in the journal Obesity, examined 51 people averaging 30 years of age. Twenty-three typically went to bed by about 3:45 a.m. and woke up by 10:45 a.m. The rest, considered normal sleepers, were in bed by 12:30 a.m. and up by 8 a.m.

The researchers found that people who stayed up late consumed an average 248 more calories daily. The diet of the night owls also included twice as much fast food, more non-diet sodas and only half as many fruits and vegetables as those with earlier sleep times. These extra calories were typically consumed at dinner and later in the evening. The study also found that those who regularly stayed up late had a higher body mass index than normal sleepers.

"The extra daily calories can mean a significant amount of weight gain -- two pounds per month -- if they are not balanced by more physical activity," the study's co-lead author, Kelly Glazer Baron, a health psychologist and a neurology instructor at Northwestern University Feinberg School of Medicine, said in a university news release.

The researchers suggest the reason behind the weight gain may be that healthier foods are not readily available at night, or that night owls tend to prefer foods that are higher in calories. The study concludes that eating habits are linked to sleeping patterns, and that when you eat may be just as important as what you eat.

"Human circadian rhythms in sleep and metabolism are synchronized to the daily rotation of the earth, so that when the sun goes down you are supposed to be sleeping, not eating," the study's senior author Dr. Phyllis Zee, professor of neurology and director of the Sleep and Circadian Rhythms Research Program at Feinberg and medical director of the Sleep Disorders Center at Feinberg and Northwestern Memorial Hospital, said in the news release. "When sleep and eating are not aligned with the body's internal clock, it can lead to changes in appetite and metabolism, which could lead to weight gain."

The study's authors also pointed out that people who eat unhealthy foods at the wrong time of day may increase their risk of stroke, heart disease and gastrointestinal disorders.

More information

The U.S. Centers for Disease Control and Prevention offers detailed information about the causes and dangers associated with obesity.

One in seven strokes happens during sleep

By Alison McCook

Reuters Health

Monday, May 9, 2011

NEW YORK (Reuters Health) – Nearly 15 percent of people who have a stroke are not eligible for clot-busting treatment because the stroke happened while they slept, a new study reports.

Clot-busting drugs can prevent permanent disability after a stroke - but the treatment must be given within a four-and-a-half-hour window after the stroke symptoms begin. Since people who have a stroke while asleep can't know when it occurred, they can't get the treatment if they slept for more than four and a half hours, explained study author Dr. Jason Mackey at the University of Cincinnati. "They can't get the drug," he said. "That's a big issue."

When Mackey and his colleagues compared these so-called "wake-up" strokes to strokes that occur during the day, they saw no major differences between the two types, indicating that the same advice for preventing and treating daytime strokes applies to those that take place while asleep, he told Reuters Health.

Strokes that occur while people are asleep or awake are "largely indistinguishable," he noted, so people concerned about either type should focus on staying generally healthy, controlling their blood pressure, eating well, exercising, and checking their cholesterol.

Stroke can be treated if people act quickly, Mackey added, so anyone who wakes up with typical signs - such as trouble speaking or walking, or weakness on one side in the arm, face or leg - should work fast. "If you suspect anyone is having a stroke, the important thing is to call 911 immediately."

Stroke is the third leading cause of death in the United States, after heart disease and cancer.

To investigate how many strokes occur during sleep, and whether they differ from strokes that begin while people are awake, Mackey and his team reviewed medical records from people who came to emergency rooms in Ohio and Kentucky in 2005.

They identified 1,854 people who had experienced the most common kind of stroke, in which blood flow to the brain becomes blocked. Of those stroke patients, 273 (almost 15 percent) said they woke up with symptoms.

If 15 percent of strokes happen during sleep, an estimated 58,000 Americans each year come to an emergency room because they woke up with stroke symptoms, the authors report in the journal Neurology.

Comparing strokes that occurred while people were asleep and awake, the researchers saw no major differences. In general, people who had wake-up strokes were slightly older and their strokes were somewhat more severe, but otherwise they resembled any stroke patient, said Mackey. "These wake-up strokes look a lot like the other strokes we see."

None of the patients who woke up with symptoms received the clot-busting drug known as tPA (short for "tissue plasminogen activator"). But what if some of them had their strokes right before they woke up, instead of many hours earlier? That could have made them eligible for treatment.

Indeed, one-third of the people who experienced wake-up strokes could have received the drugs if time had not been an issue. They didn't have any other features that would disqualify them from receiving tPA, such as high blood pressure or a recent surgery.

"A substantial proportion of these patients do not have any reason why they could not get the drug," said Mackey.

The reason doctors hesitate to administer tPA after that crucial time window, he explained, is that it comes with a risk of bleeding in the brain, and research has not shown any benefits if it's administered long after symptoms began.

The next step, said Mackey, is to investigate how to estimate when wake-up strokes actually occurred, so clinicians can determine which people who wake up with symptoms can receive tPA, "so we can give them a chance."

Source: http://bit.ly/k9sD1e

Neurology, online May 9, 2011.

After Heart Attack, Certain Painkillers May Raise Risk for Recurrence

By Maureen Salamon
HealthDay Reporter

HealthDay News

Monday, May 9, 2011

MONDAY, May 9 (HealthDay News) -- People with a history of heart attack are at increased risk of suffering another attack or dying after even a week of taking certain types of prescription and over-the-counter painkillers, including Advil, Motrin or Voltarin, a large new study suggests.

Danish researchers analyzed nationwide records of almost 84,000 heart attack survivors and found that those who used certain non-steroidal anti-inflammatory drugs (NSAID) for one week faced a 45 percent heightened risk of another heart attack. Three months' use raised the risk to 55 percent.

The results reinforce a 2007 American Heart Association statement advising doctors about the risk of NSAID use among heart patients and recommending the drugs be used only in the lowest dose and for the shortest duration necessary.

"The present results indicate there is no apparent safe therapeutic window for NSAIDs in patients with prior [heart attack], and challenge the current recommendations of low-dose and short-term use of NSAIDs as being safe," said study author Dr. Anne-Marie Schjerning Olsen, a research fellow at Copenhagen University in Denmark.

The study is published online May 9 in the journal Circulation.

The most common NSAIDs prescribed to study participants were ibuprofen (Advil, Motrin) and diclofenac (Cataflam, Voltaren). Diclofenac carried the highest cardiovascular risk, even greater than rofecoxib (Vioxx), an NSAID banned in the United States in 2004 because of a higher rate of heart attacks and strokes among those taking it.

The U.S. Food and Drug Administration recently issued a warning that diclofenac should not be used by patients recovering from heart surgery.

One popular NSAID, naproxen (Aleve), was not associated with a greater risk of death or recurrent heart attack in the study, although it has been linked to gastrointestinal bleeding.

"We were surprised that commonly used NSAIDs such as diclofenac, which in some countries is available over the counter without any expert advice on potential side effects, were associated with increased risk ... and the risk continued to persist during the course of treatment," Olsen said.

All NSAIDs block the production of the COX enzyme, which comes in two forms. Drugs inhibiting the COX-2 enzyme (these include Celebrex) have a higher chance of associated blood clots than other NSAIDs inhibiting the COX-1 type, said Dr. Elliott Antman, professor of medicine at Brigham and Women's Hospital and Harvard Medical School in Boston.

"For example, aspirin -- an NSAID with blood-thinning properties -- blocks the COX-1 enzyme," Antman noted, "and has long been considered useful in preventing heart attacks when used in low doses." Both Antman and Olsen agreed that, at the low dose typically given to patients, daily aspirin should pose no added risk for recurrence of heart attack.

Otherwise, the results of the new "are not surprising to us, and we felt it actually endorsed the recommendations we made," said Antman, who was also the lead author of the AHA's 2007 NSAIDs advisory.

"We felt there was a risk of using NSAIDs if the patient had ischemic heart disease or was at risk for it . . . we were not convinced for any period of time that these were safe," Antman added.

Olsen and her team noted that the new study was limited by its observational nature, and a prospective, randomized trial would bring more certainty on the issue. But the data was comprehensive because it came from the Danish National Patient Registry, she said, as well as a national prescription registry that has recorded every drug prescribed to citizens since 1997.

Among the nearly 84,000 heart attack survivors analyzed, whose average age was 68, more than 42 percent had at least one prescription for an NSAID, according to the study. Low-dose ibuprofen is the only NSAID available over-the-counter in Denmark, so its use was unlikely to significantly affect study results, Olsen said.

Antman said heart patients will sometimes use NSAIDs despite the risks if they suffer severe pain from conditions such as rheumatoid arthritis or lupus. Non-drug pain relief methods, such as physical therapy, heat and splints, or other types of pain relievers should be tried before resorting to NSAIDS, he said.

"Some patients have such debilitating arthritis that we need to work down the list [of NSAIDs], recognizing as we get down the list we're getting into increasingly dangerous territory," Antman said.

"If they're on one, they shouldn't stay on it. Many doctors don't monitor medication use and patients stay on long past flare-ups."

More information

The American Academy of Orthopaedic Surgeons has more information about NSAIDs.

Some get colonoscopies too frequently: study

By Genevra Pittman

Reuters Health

Monday, May 9, 2011

NEW YORK (Reuters Health) – Many patients are getting screened for colorectal cancer more often than guidelines recommend, hints a new study.

That finding, along with other research published today in Archives of Internal Medicine, suggest that doctors need to better target the tests to patients who are most likely to benefit, and conserve limited screening resources and prevent complications by sticking to recommendations more closely, researchers said.

When colonoscopies are done according to guidelines, they "should lead to a dramatic reduction in colon cancer," Dr. James Goodwin, one of the researchers from the University of Texas Medical Branch in Galveston, told Reuters Health.

However, he said, "You cause more harm than good when you're screening too frequently. It's a bad thing to do for the patient."

U.S. cancer guidelines recommend testing middle-aged and older adults with a normal cancer risk every 10 years for colorectal cancer using colonoscopy. More frequent screening doesn't pay off because the procedure is uncomfortable and invasive with a risk of complications and costs a few thousand dollars -- and because this type of cancer typically grows very slowly, experts have determined.

Another kind of test for colorectal cancer, which looks for blood in the stool, is less invasive but must be done every year, according to guidelines. It also catches early cases of cancer, as opposed to colonoscopies, which are capable of finding the warning signs of cancer before it has actually developed, Goodwin explained.

The American Cancer Society expects about 100,000 people in the U.S. to be diagnosed with colon cancer this year, and another 40,000 with rectal cancer.

In one of the two new studies, Goodwin and his colleagues followed a group of 24,000 Medicare recipients, age 66 and older, who had normal results on their first colonoscopy. Unless they developed symptoms that hinted at colorectal cancer, those patients shouldn't get screened again for another decade, according to guidelines.

But over the next 7 years, about 1 in 4 of them had another colonoscopy with no clear medical reason listed in their records.

It's particularly important to limit the number of unnecessary colonoscopies because about 1 in 1,000 people who get the test will end up in the hospital from a complication, Goodwin said. Those potential complications include major bleeding or a tear in the colon.

The second study looked at about 200 military veterans age 70 and older who tested positive for blood in their stool. In the next 7 years, about half of them went on to have a colonoscopy - which can more definitively diagnose colorectal cancer and pinpoint its location - and half of them did not.

Dr. Christine Kistler of the University of North Carolina at Chapel Hill, who led the study, and her colleagues found that while a few of the patients who didn't have a follow-up colonoscopy were diagnosed with colorectal cancer later, about half of them died within 5 years from a different cause - suggesting the first test may not really have been necessary for many of them in the first place.

The finding "argues against this one-size-fits-all, screen everybody" mentality, Kistler told Reuters Health. "We really need to target screening to those patients that are going to benefit from it," including younger and healthier people.

"If you're going to die in 5 years, why would we subject you to colonoscopies and biopsies?" said Kistler.

Patients with a longer life expectancy had a better chance of benefiting from screening, while older and sicker patients were more likely to experience the burdens of screening - hassle, discomfort, and a risk of complications and further procedures - without any benefit.

Even before doing a non-invasive fecal blood test, Kistler said, "we need to do a better job of starting to think about, what's the right test for the right patient?"

Sometimes, if a patient has already had a colonoscopy recently and has no cancer symptoms, or is old and sick enough so that having early stage colorectal cancer might not matter so much, that answer might be no test, at least for the time being, the researchers reported.

The findings should not dissuade most people from getting routine colonoscopies or other tests for colorectal cancer, said Dr. Michael LeFevre, a family doctor and co-chair of the United States Preventive Services Task Force, a federally-supported expert panel that makes screening recommendations.

Colorectal cancer "is one of the conditions for which we have very good science that screening saves lives," LeFevre told Reuters Health. And, he said, "we believe that many people are under-screened."

But he agreed that evidence shows that screening too often - or in very elderly patients - will generally do more harm than good, and that many doctors haven't fully gotten on board with screening guidelines.

Sources: http://bit.ly/jnEvS7 and http://bit.ly/m5zy8Y

 Archives of Internal Medicine, online May 9, 2011.

Popular Heartburn Meds May Boost Fracture Risk

By Maureen Salamon
HealthDay Reporter

HealthDay News

Monday, May 9, 2011

MONDAY, May 9 (HealthDay News) -- Reinforcing U.S. health officials' concerns, new Korean research suggests that long-term use of popular heartburn drugs such as Prilosec, Prevacid and Nexium is linked to an increased risk of fractures.

Scientists conducting a meta-analysis of 11 studies published between 1997 and 2011 found that proton pump inhibitors (PPIs), which reduce stomach acid production, were associated with a 29 percent increased risk of fracture. This included a 31 percent higher risk of hip fractures and a 54 percent heightened risk of vertebral fractures.

Another class of heartburn drugs known as H2-receptor antagonists or H2 blockers -- which include brand names such as Zantac and Pepcid -- were not significantly linked to fracture risk, according to the study authors. H2 blockers, however, are less powerful than PPIs at suppressing acid production, blocking only about 70 percent rather than the estimated 98 percent that can be blocked by PPIs.

"It is difficult to say uniformly what the absolute risk is because fracture risk shows many differences according to age, sex, race and ethnicity," said study lead author Dr. Chun-Sick Eom, a clinical instructor in the Department of Family Medicine at Hallym University Hospital in Chuncheon, Korea.

"Clinicians should carefully consider their decision to prescribe PPIs for patients at elevated risk for fracture, especially women older than 65 years of age," he added. "We recommend that drug doses be chosen thoughtfully with consideration of what is necessary to achieve desired therapeutic goals."

In addition, a subset of high-quality studies -- and studies adjusting for at least five variables that could also influence fracture risk -- did show an increase in fractures in people taking H2 blockers. For this reason, the study authors also recommended further study on that topic.

The study is published in the May/June issue of the journal Annals of Family Medicine.

In May 2010, the U.S. Food and Drug Administration decided that PPIs would carry a warning on their labels about their possible fracture risk. The drugs -- which include esomeprazole (Nexium), dexlansoprazole (Dexilant), omeprazole (Prilosec, Zegerid), lansoprazole (Prevacid), pantoprazole (Protonix) and rabeprazole (Aciphex) -- are used to treat stomach and small intestine ulcers, gastro-esophageal reflux disease (GERD) and inflammation of the esophagus.

Acid suppressors are the second leading medication used worldwide, Eom said, with sales in the United States in 2005 totaling nearly $27 billion.

PPIs and H2 blockers are thought to have different effects on bone metabolism, Eom noted, accounting for their disparate fracture risks. PPIs may interfere with the digestive tract's ability to absorb calcium -- a process aided by acid -- as well as the process of new bone cell growth.

Eom acknowledged that the study was limited by lack of access to individual data on nutrients that might have affected participants' fracture risks.

An editorial accompanying the study noted that the key was to balance absolute risks and benefits -- for physicians to reduce PPI use whenever appropriate, but not to worry about using them for patients such as those with acute gastric ulcers or other potentially life-threatening conditions.

Dr. David Bernstein, chief of the division of gastroenterology at North Shore University Hospital in Manhasset, N.Y., said that while the study was observational, it should prompt physicians to question the ongoing need for patients to take acid-suppressing drugs.

"We need to look at it case by case," Bernstein said. "If someone has uncontrollable reflux and needs PPI therapy long-term, they're probably going to get it. They feel better, and it's easy."

But, "at some point, the doctor and patient need to think of a different strategy -- either stop the medication or switch medications," he added. "We should give the minimal amount for the patient to get well, and then stop."

More information

The U.S. National Library of Medicine has more information about heartburn.

Parsley, Celery Carry Crucial Component for Fight Against Breast Cancer, Study Suggests

ScienceDaily

Monday, May 9, 2011

ScienceDaily (May 9, 2011) — Parsley is usually used as a decorative accent to a scrumptious meal, but don't set it aside just yet. In a new study, a University of Missouri researcher has found that a compound in parsley and other plant products, including fruits and nuts, can stop certain breast cancer tumor cells from multiplying and growing. The study was published recently in Cancer Prevention Research.

In his study, Salman Hyder, the Zalk Endowed Professor in Tumor Angiogenesis and professor of biomedical sciences in the College of Veterinary Medicine and the Dalton Cardiovascular Research Center, exposed rats with a certain type of breast cancer to apigenin, a common compound found in parsley and other plant products. The rats that were exposed to the apigenin developed fewer tumors and experienced significant delays in tumor formation compared to those rats that were not exposed to apigenin. Hyder believes this finding could impact women who are taking certain hormone replacement therapies.

"Six to 10 million women in the United States receive hormone replacement therapy (HRT)," Hyder said. "We know that certain synthetic hormones used in HRT accelerate breast tumor development. In our study, we exposed the rats to one of the chemicals used in the most common HRTs received in the United States -- a progestin called medroxyprogesterone acetate (MPA) -- which also happens to be the same synthetic hormone that accelerates breast tumor development."

When tumor cells develop in the breast in response to MPA, they encourage new blood vessels to form within tumors. The blood vessels then supply needed nutrients for the tumors to grow and multiply. Hyder found that apigenin blocked new blood vessel formation, thereby delaying, and sometimes stopping, the development of the tumors. Hyder also found that the compound reduced the overall number of tumors. However, while apigenin did delay tumor growth, it did not stop the initial formation of cancer cells within the breast.

Apigenin is most prevalent in parsley and celery, but can also be found in apples, oranges, nuts and other plant products. However, apigenin is not absorbed efficiently into the bloodstream, so scientists are unsure of how much can or should be ingested.

"We don't have specific dosage for humans yet," Hyder said. "However, it appears that keeping a minimal level of apigenin in the bloodstream is important to delay the onset of breast cancer that progresses in response to progestins such as MPA. It's probably a good idea to eat a little parsley and some fruit every day to ensure the minimal amount. However, you can also find this compound in pill supplements in the health food section of many stores. Of course, you should always check with your doctor before making any major changes to your diet or lifestyle."

The next phrase of studies should include human clinical trials to determine the appropriate dosage amount, Hyder said. He believes further study on humans is necessary to address any health and safety issues that might exist.

The research team included Benford Mafuvadze, doctoral student in biomedical sciences, Indira Benakanakere, research scientist Dalton Cardiovascular Research Center; Franklin Lopez, research fellow in the Department of Veterinary Pathobiology; Cynthia Besch-Williford, associate professor of veterinary pathobiology, and Mark Ellersieck, research professor of statistics in the College of Arts and Science.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Journal Reference:

B. Mafuvadze, I. Benakanakere, F. Lopez, C. L. Besch-Williford, M. Ellersieck, S. M. Hyder. Apigenin prevents development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats. Cancer Prevention Research, 2011; DOI: 10.1158/1940-6207.CAPR-10-0382