Fasting may reduce chemo side-effects

A few days of fasting might help protect patients from some of the unpleasant and dangerous side-effects of cancer chemotherapy, researchers reported on Tuesday.

They said mice given a high dose of chemotherapy after fasting thrived while half of a group of well-fed mice died, they reported in the Proceedings of the National Academy of Sciences.

The researchers stressed that people should not try this on their own yet but said the findings might lead to a way to use chemotherapy to more effectively kill tumors while sparing healthy cells.

Valter Longo of the University of Southern California and colleagues first tested yeast cells, then human cells in lab dishes. They found healthy cells starved of nutrients survived the ravages of chemotherapy -- but not cancer cells.

"In theory, it opens up new treatment approaches that will allow higher doses of chemotherapy. It's a direction that's worth pursuing in clinical trials in humans," cancer researcher Pinchas Cohen of the University of California, Los Angeles, who was not involved in the study, said in a statement.

Longo and colleagues said animals fed a low-calorie diet live longer, in part because their cells can resist stress better. They also noticed that starved cells go into a kind of hibernation mode, while cancer cells form tumors because they lack an "off" position, growing uncontrollably.

Longo wondered if the starvation response might be a way to differentiate healthy cells from cancer cells. One reason chemotherapy causes side-effects is that it affects all active and growing cells -- tumors, but also hair follicles, the lining of the intestines and other cells.

"Here, we tested the hypothesis that short-term starvation or low glucose/low serum can protect mammalian cells but not or to a lesser extent cancer cells, against high doses of oxidative damage or chemotherapy," they wrote.

"We administered an unusually high dose of etoposide (80 mg/kg) to ... mice that had been starved for 48 hours. In humans, one-third of this concentration of etoposide is considered to be a high dose and therefore in the maximum allowable range," they wrote.

The high dose killed 43 percent of the mice that were fed normally but just one starved mouse. The starved mice regained their lost weight within four days.

An even higher dose killed all of the well-fed mice from a different genetic strain but none of the starved mice, and again the mice that fasted regained their weight.

Other cancer experts said a few days of fasting would not harm most cancer patients.

"This could have applicability in maybe a majority of patients," said Dr. David Quinn of the University of Southern California.

"We have passed the stage where patients arrive at the clinic in an emaciated state. Not eating for two days is not the end of the world," agreed Felipe Sierra, director of the Biology of Aging Program at the National Institute on Aging.

Popcorn ingredient causes lung disease

A chemical used to give butter flavor to popcorn can damage the lungs and airways of mice, U.S. government experts reported on Thursday.

Tests on mice show that diacetyl, a component of artificial butter flavoring, can cause a condition known as lymphocytic bronchiolitis, said the team at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.
A popcorn seller stocks up in Barnes, southwest London July 5, 2007. A chemical used to give butter flavor to popcorn can damage the lungs and airways of mice, U.S. government experts reported on Thursday. (REUTERS/James Boardman)

The condition can lead to obliterative bronchiolitis -- or "popcorn lung" -- a rare and debilitating disease seen in workers at microwave popcorn packaging plants and at least one consumer.

At least two microwave popcorn makers -- ConAgra Foods Inc and Weaver Popcorn Co Inc -- have said recently they would stop using diacetyl.

Laboratory mice made to inhale diacetyl vapors for three months developed lymphocytic bronchiolitis, the NIEHS team said.

"This is one of the first studies to evaluate the respiratory toxicity of diacetyl at levels relevant to human health," Daniel Morgan at NIEHS, whose team led the study, said in a statement.

Writing in the journal Toxicological Sciences, the researchers said findings suggest that workplace exposure to diacetyl contributes to the development of obliterative bronchiolitis.

The hard-to-treat condition causes vague symptoms such as cough and shortness of breath, and steadily worsens, according to the U.S. Centers for Disease Control and Prevention.

Congress has been working on a bill to order quick action by the Occupational Safety and Health Administration to limit exposure to diacetyl. The House of Representatives passed a bill last year but the Senate has not acted.

The Food and Drug Administration said last September it was investigating a report of a man who came down with the life-threatening disease after eating several bags of butter-flavored microwave popcorn each day.

Memory loss declining among U.S. seniors

Older Americans are having less trouble with their memories, and it may be because they spent more time in school, U.S. researchers said on Wednesday.

They found the rate of cognitive impairment -- which includes a range of ills from significant memory loss to Alzheimer's disease -- fell 3.5 percentage points among people 70 and over between 1993 and 2002.

"We found a clear relationship. The more education people had, the better they performed on cognitive tests," said Dr. Ken Langa of the University of Michigan, whose study appears in the journal Alzheimer's & Dementia.

Langa said the research reinforces other studies that suggest people who do mentally challenging tasks early on build up a reserve of brain power that helps them withstand later injuries to the brain, such as a mini-stroke.

"Your brain is wired up differently. You can sustain more insults over your lifetime," Langa said in a telephone interview.

To test this, Langa and colleagues looked to see if there was a relationship between education and mental agility in older Americans.

They used data on 11,000 people from the Health and Retirement Study, a national survey of U.S. adults. The researchers compared data gathered in 1993 with data from 2002.

They found that in in 2002, 8.7 percent of those aged 70 or older had cognitive impairment, down from 12.2 percent in 1993. "We think education is part of the story here," Langa said.

In 1993, people who were 70 or older on average had 11 years of education. By 2002, those 70 and older had 12 years of education. "That is a relatively significant increase in the level of education," he said.

They also found that older adults with more education who did develop cognitive problems were more likely to die within two years.

Langa said the thinking is that people who have more education have developed different brain circuits that have allowed them to continue functioning at a high level.

"Once you put it off as long as you can, you are more likely to have a quicker decline and death," he said.

Langa said the results may also reflect better cardiovascular health, which can reduce strokes or other injuries that affect brain function. He said rising rates of obesity and diabetes could offset those gains.

"Cardiovascular risks have a close link to brain health," he said.

Langa said people should exercise their bodies to protect their cardiovascular health, and exercise their brains with puzzles and books.

Stem cells help rats recover function after stroke

Transplanting brain cells produced from human embryonic stem cells helped fix stroke damage in the brains of rats, according to scientists who hope to test the same thing in people whithin about five years.

Researchers have been looking for ways to repair the brain damage from a stroke, which can cause permanent disability. In a study published on Tuesday, researchers at Stanford University School of Medicine in California reported that treatment involving human embryonic stem cells may be a solution.

Embryonic stem cells are the master cells that give rise to every cell and tissue in the body.

The Stanford team reported they restored lost limb function in rats that had stroke-related brain damage. They induced human embryonic stem cells to develop into neural stem cells that, once transplanted in the rats, developed into neurons and two other important types of brain cells.

The researchers hope to use this approach within about five years in studies involving people who have had strokes.

"We have a lot of evidence that we'll be able to use this kind of stem cell regenerative therapy in patients, including stroke patients," Stanford's Dr. Gary Steinberg, who helped lead the study, said in a telephone interview.

Writing in the Public Library of Science journal PLoS ONE, Steinberg's team described how they caused strokes in 10 rats and then transplanted neural stem cells into their brains.

The cells made their way to the damaged brain region and incorporated themselves into surrounding brain tissue.

The cells never grew uncontrollably into tumors in lab dishes or inside the rats, the scientists said. The transplanted cells helped repair the stroke damage and enabled the rats to recover lost function in front legs weakened as a result of the stroke, they added.

"It was not quite back to normal but, at least in the rat, it looks like it's going to be close to normal -- very impressive," Steinberg said.

"Now remember, this is a rat, not a human. We still have to make that step. But if we could achieve that kind of recovery in humans, we would have a great therapy," Steinberg added.

In a stroke, the blood supply to any part of the brain is blocked. This can occur when a blood vessel bringing blood to the brain is blocked by a blood clot, or when a blood vessel bursts, causing blood to leak into the brain.

If blood flow is halted for more than a few seconds, the brain is deprived of blood and oxygen, brain cells die and permanent damage can result.

Some people oppose the use of human embryonic stem cells on ethical grounds because creating the reservoirs of these cells for use in research involves the destruction of human embryos.

Music matters for stroke patients, study finds

A little Beethoven is good for the brain, according to a Finnish study published on Wednesday showing that music helps people recover more quickly from strokes.

And patients who listened to a few hours of music each day soon after a stroke also improved their verbal memory and were in a better mood compared to patients who did not listen to music or used audio books, the researchers said.

Music therapy has long been used in a range of treatments but the study published in the journal Brain is the first to show the effect in people, they added.

"These findings demonstrate for the first time that music listening during the early post-stroke stage can enhance cognitive recovery and prevent negative mood," the researchers wrote.

Strokes, which occur when blood flow to the brain is blocked, can kill brain tissue and are one of the worldwide leading causes of death and permanent disability. Treatments include blood thinning drugs and attempts to lower cholesterol.

The study involved 60 people who recently had a stroke of the middle cerebral artery in the left or right side of the brain. This is the most common stroke and can affect motor control, speech and a range of other cognitive functions.

One group listened to their favourite music every day or used audio books while another did not listen to any music. All volunteers received standard rehabilitation treatment.

Three months after stroke music listeners showed a 60 percent better improvement in verbal memory compared to an 18 percent benefit for those using audio books and 29 percent for people who did not listen to either.

The ability to focus attention also improved by 17 percent in music listeners, said Teppo Sarkamo, a psychologist at the Cognitive Brain Research Unit at the University of Helsinki, who led the study.

"We can't say what is happening in the brain but based on previous research and theory it may be music listening could actually activate the brain areas that are recovering," he said in a telephone interview.

Music might also in some way activate more general mechanisms that repair and renew the brain's neural networks after stroke, Sarkamo said.

Larger studies are needed to better understand exactly what is going on but these findings show that music may offer a cheap, easy additional treatment for stroke patients, he said.

"This could be considered a pilot study," Sarkamo said. "It is a promising start.

Cardiac arrest: avoid nights, weekend

People who have a cardiac arrest in the hospital at night or on the weekend are far less likely to survive than those who suffer one during the day, U.S. researchers said on Tuesday.

Studies suggest this may be at least partly because of inadequate staffing at off-peak hours.

The researchers found only 14.7 percent of people whose hearts stop pumping during the night survive, compared with nearly 20 percent of people during the day.

Those who had a cardiac arrest at around 3 p.m. had the survival rate, Dr. Mary Ann Peberdy of Virginia Commonwealth University in Richmond and colleagues reported in the Journal of the American Medical Association.

The only part of the hospital with difference in survival day or night was the emergency department. "That survival difference by time of day was there regardless of where we looked, except in the emergency department," Peberdy said.

She said emergency departments are the one place in hospitals constantly staffed by senior-level physicians.

Cardiac arrest occurs when the heart stops circulating blood. Without cardiopulmonary resuscitation or CPR and often a shock from a defibrillator, patients can die within minutes.

"Doing the right thing and doing it quickly is very important," Peberdy said.

She said studies at individual hospitals suggested staffing played a role in whether a patient survived a cardiac arrest.

Other studies have shown that doctors make more mistakes at night, hospitals have fewer nurses per patient working at night and that fewer experienced supervisors work the night shift.

TIME TRUMPS OTHER FACTORS

Peberdy wanted to see how this affected survival of cardiac arrest. Her team scoured the National Registry of Cardiopulmonary Resuscitation, which included survival data for more than 86,000 adults who had heart attacks in more than 500 U.S. hospitals between January 2000 and February 2007.

They split up the data by time of day, with the day/evening defined as 7 a.m.-10:59 p.m., night as 11 p.m.-6.59 a.m. and weekends starting at 11 p.m. Friday and running through 6.59 a.m. Monday.

"We factored in how sick people were, what their initial rhythms were. None of that overshadowed the time of day," Peberdy said in a telephone interview.

"Weekend nights were pretty much the same as week nights. Weekend days were kind of in between week days and nights," she said.

She said the difference by time of day held regardless of whether a patient was in a bed with a heart monitor or even in the intensive care unit.

"I think the study confirms what some of us have suspected for a while: That how we staff the hospital determines how well patients do," said Dr. Graham Nichol who helps oversee the NRCPR registry for the American Heart Association.

Peberdy said the study suggests hospitals need to focus on improving their resuscitation systems in off-hours

Healthy elderly lifestyle key to longer life

You're never too old to reap the benefits of a healthful lifestyle, according to researchers who found that doing things like exercising and not smoking at age 70 greatly raises one's chances of living to age 90.

The researchers focused on what people can do in their early elderly years to live longer while maintaining good health and physical function -- a vital issue as the population ages in the United States and many other countries.

For 25 years, they tracked about 2,400 male doctors whose average age was 72 when they entered the study in the early 1980s.

Those who exercised two to four times per week, did not smoke, maintained normal body weight and blood pressure, and avoided diabetes had a 54 percent chance of living to 90.

Doing any one or combination of them also were beneficial. But men who did none of them had only a 4 percent chance of reaching age 90, the researchers reported on Monday in the Archives of Internal Medicine.

"This isn't surprising so much as it's reassuring," said Dr. Laurel Yates of Brigham and Women's Hospital and Harvard Medical School in Boston, who led the study.

"All of these factors are considered common sense -- good medical management -- in terms of emphasizing: don't smoke, let's do blood pressure control and weight management, and do exercise," Yates said in a telephone interview.

'DON'T SMOKE, DO EXERCISE'

Yates said the lifestyle message commonly has been aimed at middle-aged people, so it is helpful to see that such lifestyle factors can also help the elderly add healthy years.

"Lifestyle changes are the hardest ones to make. It's a lot easier to take a pill. So the onus is on an individual," Yates said. "If you're going to ask what's the one thing that I could do, I would say do two things: don't smoke and do exercise."

The researchers also found that the men who lived to at least 90 enjoyed better physical function and mental well-being late in their lives than men who died at a younger age.

Yates said research has shown that genetics counts for only about 25 to 30 percent in determining how long people live, with other factors playing a bigger role.

"Most people would say they don't want to have extra years added to their life if those years are going to be ones of disability and disease. And I think it is reassuring that there is something a person can do to help increase the probability of having extra years that are good ones," Yates said.

Another study in the same journal, led by Dr. Dellara Terry of Boston University School of Medicine and Boston Medical Center, looked at 523 women and 216 men age 97 or older.

Terry's team found that about a third of these people got to this advanced age despite having developed age-associated disease before age 85 such as chronic obstructive pulmonary disease, dementia, diabetes, heart disease, high blood pressure, osteoporosis, Parkinson's disease or stroke.

Other recent research has quantified how certain behaviors affect longevity. British researchers who tracked 20,000 people said last month those who exercised, avoided smoking, drank moderately and ate lots of fruit and vegetables lived 14 years longer on average than people who did none of these things.

Autopsies forecast surge in U.S. heart disease

Autopsies of adults who died young of unnatural causes show many already had clogged arteries, U.S. and Canadian researchers said on Monday in a study that suggests heart disease may be on the upswing.

The researchers said their findings suggest a four-decade-long trend of declines in heart disease may be about to come to a screeching halt.

They studied autopsy reports from younger people in one Minnesota county who died from accidents, suicide and murder and found most had clogged arteries and more than 8 percent had significant disease.

"What they observed was a bit shocking," said S. Jay Olshansky of the University of Illinois at Chicago, who wrote an editorial on the research, published in the Archives of Internal Medicine.

"It is the most definitive evidence I've seen suggesting that today's younger and middle-aged generations may be heading for an increase in their risks of heart disease," he said.

The researchers from the Mayo Clinic in Minnesota and the University of British Columbia in Vancouver looked at autopsy data from residents of Olmsted County, Minnesota, who died between 1981 and 2004 from unnatural causes.

During that time, 8.2 percent of 425 people aged 16 to 64 had high-grade disease and 83 percent had the beginnings of coronary artery disease.

Mayo's Cynthia Leibson and colleagues found declines in the grade of coronary artery disease ended after 1995 and began to climb after 2000.

"Declines in coronary artery disease appear to have ended and there is some suggestion that they might be increasing," Leibson said in a telephone interview.

She said it is not yet clear to what extent obesity and diabetes contributed to this, but the researchers plan to study this in the same group of patients.

'PERFECT STORM'

Olshansky, in a telephone interview, said rates of heart disease in the United States climbed steadily in the 20th century until the 1960s, and then began falling, helped by changes in lifestyle and declines in smoking. But then, a confluence of changes occurred.

"It was more or less a perfect storm," he said, citing the introduction of computers and a more sedentary lifestyle, the growth of fast-food chains and larger portion sizes, reduced physical education in schools and increased consumption of high-fructose corn syrup.

"It led to this explosion of obesity," Olshansky said.

A second study in the same journal confirms the trends.

Dr. Philip Mellen of the Hattiesburg Clinic in Mississippi analyzed national diet and nutrition data from a large federal study to see if patients with high blood pressure were adhering to a diet known to help control high blood pressure, a known cause of heart attacks and strokes.

They looked at data collected from 1988-1994, a period before a study in 1997 showed a diet high in fruits, vegetables and low-fat dairy products could significantly lower blood pressure. They compared this to data from 1999 to 2004.

What they found was people with hypertension were eating worse, not better. "The dietary quality has deteriorated over the last 15 years," Mellen said in a telephone interview.

"In our study, the youngest age group was the age group with the worse disease," he said. "This age group will have major problems as they continue to age."

Heart attacks drop after Italy's smoking ban

Italy's 2005 smoking ban has led to a sharp fall in heart attacks, researchers reported on Monday in a finding they said shows that such laws really do improve public health.

Following the ban the number of heart attacks in men and women aged 35-64 -- people most likely to be exposed to smoke in cafes, bars and restaurants -- fell 11 percent, the researchers said.

The findings showed the health benefits of European smoking bans in public places, said Francesco Forastiere, an epidemiologist at the Rome Health Authority who led the study.

"Most of this change is due to the decreased impact of passive smoke," he said in a telephone interview. "This is ... important because it shows the impact of a health intervention that can be achieved in other countries."

Italy, Britain, Ireland and a number of other European countries have outlawed smoking in public places, and many health experts are urging the European Union to adopt an even wider ban.

The ban in Italy, where the researchers said about 30 percent of men and 20 percent of women smoke, prohibited smoking cigarettes in all indoor public places such as offices, retail shops, restaurants, pubs and discos.

STRONGLY ENFORCED

"Smoking bans should be extended to all possible countries and smoking bans in the workplace should be strongly enforced," the researchers wrote.

Writing in the American Heart Association journal Circulation, the researchers compared the rate of heart attacks from 2000 to 2004 to those occurring in the year after the ban was enforced.

The team analyzed hospital records and adjusted for heat waves, flu epidemics, air pollution and other factors that could have contributed to heart attacks. The researchers also took daily measurements on air quality in 40 public places.

"The smoking ban in Italy is working and having a real protective effect on population health," Forastiere said.

After the ban, cigarette sales also fell 5.5 percent but the researchers attributed the health benefits seen in the study to reduced exposure to passive smoke.

They said young men and women living in poorer areas appeared to have the greatest health benefit after the ban.

Smoking kills about four million people each year while about a quarter of deaths related to heart disease are due to cigarettes, according to the World Health Organisation.