Showing posts with label medical researches. Show all posts
Showing posts with label medical researches. Show all posts

2 Dec 2011

Eating fish reduces risk of Alzheimer’s disease

People who eat baked or broiled fish on a weekly basis may be improving their brain health and reducing their risk of developing mild cognitive impairment (MCI) and Alzheimer’s disease, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).
“This is the first study to establish a direct relationship between fish consumption, brain structure and Alzheimer’s risk,” said Cyrus Raji, M.D., Ph.D., from the University of Pittsburgh Medical Center and the University of Pittsburgh School of Medicine. “The results showed that people who consumed baked or broiled fish at least one time per week had better preservation of gray matter volume on MRI in brain areas at risk for Alzheimer’s disease.”

Alzheimer’s disease is an incurable, progressive brain disease that slowly destroys memory and cognitive skills. According to the National Institute on Aging, as many as 5.1 million Americans may have Alzheimer’s disease. In MCI, memory loss is present but to a lesser extent than in Alzheimer’s disease. People with MCI often go on to develop Alzheimer’s disease.

For the study, 260 cognitively normal individuals were selected from the Cardiovascular Health Study. Information on fish consumption was gathered using the National Cancer Institute Food Frequency Questionnaire. There were 163 patients who consumed fish on a weekly basis, and the majority ate fish one to four times per week. Each patient underwent 3-D volumetric MRI of the brain. Voxel-based morphometry, a brain mapping technique that measures gray matter volume, was used to model the relationship between weekly fish consumption at baseline and brain structure 10 years later. The data were then analyzed to determine if gray matter volume preservation associated with fish consumption reduced risk for Alzheimer’s disease. The study controlled for age, gender, education, race, obesity, physical activity, and the presence or absence of apolipoprotein E4 (ApoE4), a gene that increases the risk of developing Alzheimer’s.

Gray matter volume is crucial to brain health. When it remains higher, brain health is being maintained. Decreases in gray matter volume indicate that brain cells are shrinking.
The findings showed that consumption of baked or broiled fish on a weekly basis was positively associated with gray matter volumes in several areas of the brain. Greater hippocampal, posterior cingulate and orbital frontal cortex volumes in relation to fish consumption reduced the risk for five-year decline to MCI or Alzheimer’s by almost five-fold.

“Consuming baked or broiled fish promotes stronger neurons in the brain’s gray matter by making them larger and healthier,” Dr. Raji said. “This simple lifestyle choice increases the brain’s resistance to Alzheimer’s disease and lowers risk for the disorder.”
The results also demonstrated increased levels of cognition in people who ate baked or broiled fish.
“Working memory, which allows people to focus on tasks and commit information to short-term memory, is one of the most important cognitive domains,” Dr. Raji said. “Working memory is destroyed by Alzheimer’s disease. We found higher levels of working memory in people who ate baked or broiled fish on a weekly basis, even when accounting for other factors, such as education, age, gender and physical activity.”
Eating fried fish, on the other hand, was not shown to increase brain volume or protect against cognitive decline.
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30 Nov 2011

Scientists question if wi-fi laptops can damage sperm/BBC News

Scientists are questioning if using wi-fi on a laptop to roam the internet could harm a man's fertility, after lab work suggested ejaculated sperm were significantly damaged after only four hours of exposure.
The benchside tests showed sperm were less able to swim and had changes in the genetic code that they carry.

Experts stress this does not mean the same would occur in a real-life setting and say men should not worry unduly.
But they are recommending more studies.
The preliminary research, published in the journal Fertility and Sterility, looked at semen samples from 29 healthy donors.
Each donor sample was separated out into two pots. One of these pots was then stored for four hours next to a laptop that was wirelessly connected to the internet. The other was stored under identical conditions, minus the laptop.
The scientists, from Argentina and the US, suspect that the effect seen is unrelated to the heat kicked out by a laptop, although heat can damage sperm.
Under investigation

The UK's Health Protection Agency has been closely monitoring the safety of wi-fi.
It says people using wi-fi, or those in the proximity of wi-fi equipment, are exposed to the radio signals it emits - and some of the transmitted energy in the signals is absorbed in their bodies.
However, the signals are very low power.
The HPA says there is no consistent evidence to date that exposure to radio signals from wi-fi adversely affects the health of the general population.

UK fertility expert Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, said: "The study is very well conducted, but we should be cautious about what it may infer about the fertility of men who regularly use laptops with wi-fi on their laps.
"Ejaculated sperm are particularly sensitive to many factors because outside the body they don't have the protection of the other cells, tissues and fluids of the body in which they are stored before ejaculation. Therefore, we cannot infer from this study that because a man might use a laptop with wi-fi on his lap for more than four hours then his sperm will necessarily be damaged and he will be less fertile.
"We need large epidemiological studies to determine this, and to my knowledge these have not yet been performed."

He said men should still be cautious about balancing a laptop on their thighs for hours on end.
"We know from other studies that the bottom of laptops can become incredibly hot and inadvertent testicular heating is a risk factor for poor sperm quality.
"There is a case report of a man who burnt his penis after using a laptop resting on his lap for a long time. Therefore, there are many reasons to try and use a laptop on a table where possible, and this may in itself ameliorate any theoretical concerns about wi-fi."
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28 Nov 2011

An Egg a Day Raises Risk of Diabetes -Researchers

People who eat eggs every day may substantially increase their risk of type 2 diabetes, researchers here said.

Men with the highest level of egg consumption -- at seven or more per week -- were 58% more likely to develop type 2 diabetes than those who did not eat eggs, and women were 77% more likely to become diabetic if they ate at least an egg a day, Luc Djoussé, M.D., D.Sc., of Brigham and Women's Hospital and Harvard, and colleagues reported online in Diabetes Care.

Levels of egg intake above one a week also incrementally increased diabetes risk in both men and women (both P<0.0001 for trend), the researchers said.

Eggs are a major source of dietary cholesterol (about 200 mg per egg) and add about 1.5 g of saturated fat each to the diet, both of which would be expected to increase diabetes risk, they said.
Action Points

    Explain to interested patients that the average one-egg-a-week consumption was not associated with increased diabetes risk.

    Note that eggs may influence glucose metabolism primarily through their effect on cholesterol, although the researchers noted that the observational study could not determine the mechanism.

But each egg also contributes about 0.7 g of polyunsaturated fat, which may confer a lower risk of type 2 diabetes, the researchers noted.

The limited, primarily animal model, evidence for an effect of eggs or dietary cholesterol on glucose metabolism has been inconsistent, they added.

To sort out the effects, the researchers analyzed two large prospective trials that included food frequency questionnaires.

Their analysis included 20,703 male physicians without baseline diabetes from the Physicians' Health Study I (1982-2007) and 36,295 similarly diabetes-free female health professionals from the Women's Health Study (1992-2007).

Both studies were originally designed as randomized trials of vitamin supplementation and aspirin for prevention of heart disease.

Over a mean follow-up of 20.0 years in men and 11.7 years in women, 1,921 men and 2,112 women developed type 2 diabetes.

Diabetes was more common in men and women who reported eating more than the average one egg a week.

After adjustment for traditional diabetes risk factors and compared with no egg consumption at the 95% confidence interval, the hazard ratios for type 2 diabetes in men were:

    9% for less than one egg a week (hazard ratio 1.09, 0.87 to 1.37)
    9% for one egg a week (HR 1.09, 0.88 to 1.34)
    18% for two to four eggs a week (HR 1.18, 0.95 to 1.45)
    46% for five to six eggs per week (HR 1.46, 1.14 to 1.86)
    58% for seven or more eggs each week (HR 1.58, 1.25 to 2.01)

Updating egg consumption with longer follow-up among men strengthened the associations to an almost twofold risk for those in the near daily or higher intake groups (HR 1.77, 95% CI 1.39 to 2.26, and HR 1.99, 95% CI 1.23 to 3.23, respectively).

For women, the multivariate-adjusted risks, also at the 95% confidence interval, compared with no egg intake were:

    6% for less than one egg per week (HR 1.06, 0.92 to 1.22)
    -3% for one egg a week (HR 0.97, 0.83 to 1.12)
    19% for two to four eggs per week (HR 1.19, 1.03 to 1.38)
    18% for five to six eggs a week (HR 1.18, 0.88 to 1.58)
    77% for seven or more per week (HR 1.77, 1.28 to 2.43)

Data on dietary cholesterol available in the female health professional study showed higher diabetes risk with rising dietary cholesterol with hazard ratios increasing to 1.28 (95% CI 1.10 to 1.50) in the highest quintile (P<0.0001 for trend).

Adjustment for dietary cholesterol attenuated the association between diabetes and egg consumption, whereas saturated fat was not associated with type 2 diabetes and did not alter the diabetes-egg link.

The effects did not appear to be limited to those with high carbohydrate diets, hypercholesterolemia, or high body mass index.

However, the researchers acknowledged that the data did not include repeat fasting glucose, fasting insulin, and other biomarkers of glucose metabolism to "comprehensively examine possible physiologic mechanisms."

The observational studies may also have been limited by self-reporting and residual confounding, they noted.

The generalizablity may have been limited as well by the homogeneous, primarily Caucasian health professional population, which may have different behaviors than the general population, Dr. Djoussé's group said.

"Given the societal burden of type 2 diabetes," they concluded, "confirmation of these findings in other populations and exploration of possible underlying biological mechanisms are warranted."

The study was supported by grants from the National Cancer Institute and the National Heart, Lung, and Blood Institute.

Reviewed by Dori F. Zaleznik, MD; Associate Clinical Professor of Medicine, Harvard Medical School, Boston.    
(MedPage Today)
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26 Nov 2011

Acupuncture Safe in Kids, Study Finds

Treating kids with acupuncture is a common practice and generally safe, according to a new study.

“Like adults, acupuncture is very safe when applied to the children’s population,” said Jamie Starkey, an acupuncturist from the Cleveland Clinic, who did not take part in the study. “And so it basically mimics exactly what is seen in the adult population.”

Researchers at the University of Alberta studied data from different countries spanning 60 years. They looked at the association between needle acupuncture and the different adverse events in children.

Out of 279 adverse effects, 253 were mild, according to the researchers.

The other 25 adverse effects were likely related to sub-standard techniques.

Adverse effects included bruising, bleeding and worsening of symptoms after treatment.

“Any of the serious side effects that they found were definitely due in part to the clinician’s malpractice,” Starkey said. “So, it was certainly somebody who was not necessarily the most trained. The take-home message is that it is absolutely safe in both the adult and pediatric world, but you have to go to somebody who is trained.”
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25 Nov 2011

New method of nerve stimulation developed

Better Electrical Stimulation Could Help Damaged Nerves
Functional electrical stimulation (FES) was developed to help return lost function to patients with upper and lower extremity injuries and spinal cord injuries, among other applications. However, the devices, which work by stimulating neuronal activity in nerve-damaged patients, have a potential shortcoming in that the electrical currents needed for the treatment to work can also send errant signals to surrounding nerves, resulting in painful side effects.

Earlier this fall, a plastic surgery research team at Beth Israel Deaconess Medical Center (BIDMC) and an engineering team from the Massachusetts Institute of Technology (MIT), described a new method of nerve stimulation that reduces the device’s electrical threshold by 40 percent, compared with traditional FES therapy. Reported in the October 23 Advance On-line issue of the journal Nature Materials, the findings could help researchers develop a safer, more efficient FES therapy with fewer side effects.

“This new device works by manipulating the concentration of charged ions surrounding the nerve,” explains co-senior author Samuel J. Lin, MD, a surgeon in BIDMC’s Divisions of Plastic Surgery and Otolaryngology and Assistant Professor of Surgery at Harvard Medical School. “This could potentially mean reduced risk to surrounding nerves because less electrical current is required to stimulate the affected nerve.” The researchers additionally discovered that they could use the device to block signals in nearby nerve fibers, which could help prevent unwanted muscle contractions.
The research team, led by Lin and MIT Associate Professor Jongyoon Han, PhD, determined that by altering calcium ion concentrations in the fluid surrounding the nerves they could adjust the electrical impulses.
“Nerve fibers fire their signals based on the message they receive from the interaction of ions, or charged particles,” explains coauthor Ahmed M.S. Ibrahim, MD, a Research Fellow in BIDMC’s Divisions of Plastic Surgery and Otolaryngology. “We wanted to achieve the lowest current possible that would still result in positive results.” After testing the manipulation of sodium and potassium ions, the researchers determined that consistent results could be achieved by removing positively charged calcium ions from the fluid surrounding the nerves.

The newly designed method not only prevents electrical impulses from traveling along a nerve but also uses significantly less current required by existing FES therapy. “This could be of particular benefit for the treatment of patients with various forms of paralysis,” explains Lin. “The nerves that control movements and the sensory nerves that carry pain signals are extremely close together, so existing FES therapy has had limitations.”
The researchers conducted their study of this new electrochemical-stimulation method in the nerves of frogs and plan to later test it in mammalian nerves.

“This is an important step towards the design of a device to help patients suffering from nerve paralysis and chronic neurological conditions,” say Lin. “By bringing together biomedical and engineering research teams we have been able to successfully develop this new technique. Going forward, these types of collaborations will be absolutely crucial to creating new clinical treatments and enhancing patient care.”
In addition to Lin, Han and Ibrahim, study coauthors include Rohat Melik of MIT, Amr N. Rabie of BIDMC and Ain Shams University, Cairo, Egypt; David Moses of Rice University, Houston, TX; and Ara Tan of the University of Minnesota.
This study was supported, in part, by a Harvard Catalyst grant from the Harvard Clinical and Translational Science Center (National Institutes of Health) and the Massachusetts Institute of Technology.
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23 Nov 2011

New evidence links virus to brain cancer

Tilting the scales in an ongoing debate, University of Wisconsin-Madison researchers have found new evidence that human cytomegalovirus (HCMV) is associated with glioblastoma multiforme (GBM), the brain cancer that killed Sen. Edward Kennedy.
Tilting the scales in an ongoing debate, University of Wisconsin-Madison researchers have found new evidence that human cytomegalovirus (HCMV) is associated with glioblastoma multiforme (GBM), the brain cancer that killed Sen. Edward Kennedy.

The findings confirm what only a handful of scientists have found, but in a manner that University of Wisconsin School of Medicine and Public Health researchers believe enhances the scientific rigor of earlier studies.

The study, published in the advanced online edition (Nov. 16, 2011) of the Journal of Virology, hints for the first time that HCMV may work differently than other cancer-related viruses - possibly by affecting only tumor stem cells, self-renewing cells that keep the tumor growing.

The new research may place HCMV in an expanding group of viruses associated with cancer.

"As many as 15 to 20 percent of all human cancers are caused by viruses, and the number is growing," says HCMV expert Dr. Robert Kalejta, associate professor of oncology at the UW School of Medicine and Public Health (SMPH). "The viruses may not cause cancer on their own, but they play a critical role in the process."

Among others, human papilloma virus (HPV) causes cervical cancer, Epstein-Barr virus (EBV) causes lymphoma and hepatitis C virus (HCV) causes liver cancer.

HCMV's role in GBM has been debated, with many scientists and clinicians remaining skeptical. Oncologist Dr. Charles Cobbs of California Pacific Medical Center has been the main proponent of the theory that HCMV contributes to GBM.

Dr. John Kuo, assistant professor of neurological surgery and human oncology and a cancer stem cell scientist at the School of Medicine and Public Health, was one of the skeptical ones, but he says he's now convinced that HCMV is associated with human GBM specimens.

Still, the association does not prove a causal relationship between HCMV and the development of GBM, he says.

HCMV-infected cell.
"This study may open up a new unexplored area of research for this incurable disease," says Kuo, who is director of the Comprehensive Brain Tumor Program at UW Hospital and Clinics. He also coordinates clinical trials as chair of the brain tumor group at the Carbone Cancer Center.

Kuo and colleagues on the UW brain tumor team currently treat GBM patients with the standard regimen of surgery, followed by radiation and chemotherapy. More research is needed before anti-viral drugs against HCMV could be considered for clinical trials, says Kuo, whose group contributed to the Journal of Virology paper.

Two years ago, Kalejta's team added support to Cobb's position when it showed that two HCMV proteins shut down a key protein that restricts tumor growth in general.

"HCMV can also do every one of the things that are generally considered the 10 hallmarks of cancer," says Kalejta, a member of the McArdle Laboratory for Cancer Research, Carbone Cancer Center, Stem Cell and Regenerative Medicine Center and Institute for Molecular Virology at UW-Madison.

The problem with studying HCMV is that the virus is present in a harmless way in almost everyone, so scientists can't ask if HCMV-positive people are more likely to get cancer than people without HCMV.

Kalejta's postdoctoral fellow Dr. Padhma Ranganatan used a standard laboratory test, rather than the ultra-sensitive test Cobb has used, to see if HCMV was present in 75 GBM samples. The UW-Madison researchers also looked to see if the entire virus genome - all of its DNA - rather than just a portion of it was present in the tissues. Finally, they wanted to learn if all cells within the tumor or just some of them were infected.

The analysis showed that HCMV is statistically more likely to be present in GBM sample tissues than in other brain tumor and epileptic brain tissues. The whole virus genome, not a portion of it, was present in GBM samples. And the data suggested that a minority of GBM cells were infected with HCMV.

"We hypothesize that HCMV may be infecting only tumor stem cells, unlike other viruses, which infect every single tumor cell," says Kalejta. "This leads us to predict that HCMV functions by a unique mechanism that no other virus uses."

Kalejta hopes to begin looking for the new mechanism soon. If there is such a mechanism, it could open a new door in cancer biology. It would also convert many more people to the idea that HCMV plays a key role in GBM.

"But I think the tide is now turning on the debate," Kalejta says.
(via Medical Xpress)
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21 Nov 2011

Underweight people at higher post-surgery risk: study

(Reuters) - People who are underweight have a 40 percent higher risk of dying in the first month after surgery than patients who are overweight, according to new research released on Monday.
The findings suggest that body mass index, or BMI, may be useful in predicting which patients are at the greatest risk while recovering from surgery, U.S. researchers reported in the Archives of Surgery.
Prior studies looking at the role of BMI in surgery have been mixed, said George Stukenborg of the University of Virginia in Charlottesville, who worked on the study.
"Patients with low BMI are at higher risk of death 30 days after surgery," Stukenborg said in a telephone interview.
The researchers used data on nearly 190,000 patients who underwent a variety of surgeries at 183 hospitals between 2005 and 2006.
BMI is calculated by dividing weight in kilograms by height in meters squared. According to the U.S. Centers for Disease Control and Prevention, people with a BMI of 18.5 to 24.9 are normal weight, those with a BMI of 25 to 29.9 are overweight, and those with a BMI of 30 and above are obese.
To look for a link between body weight and the risk of death, they classified patients into five groups or quintiles: people with a BMI of less than 23.1; people with a BMI of 23.1 to less than 26.3; people with a BMI of 26.3 to less than 29.7; people with a BMI of 29.7 to less than 35.3; and people with a BMI of 35.3 or higher.
Overall, 2,245 or 1.7 percent of people in the study died within 30 days of surgery.
"We found patients in the lowest quintile had a 40 percent higher odds of death compared to the mid-range," said Stukenborg, referring to people in the overweight category with BMIs of 26.3 to 29.7.
Even when the researchers adjusted for type of surgery and other risk factors, those with a low BMI still had a greater risk of dying in the first month after surgery compared with plumper surgery patients.
Stukenborg said it is not clear why. The study did not track recent weight loss, so it could be that people who weighed less were sicker to begin with.
"That is a possibility," he said.
Either way, Stukenborg said doctors should consider BMI when they plan surgeries for their patients.
Being overweight or obese carries many other risk, raising chances of heart disease, diabetes, some cancers, arthritis and other conditions. Obesity-related diseases account for nearly 10 percent of medical spending in the United States or an estimated $147 billion a year.
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Study shows left side of brain more active in immoral thinking

Because the brain is so complex, researchers are forced to devise all manner of different types of tests in trying to understand not just how it works, but which parts of it do what. To that end, a diverse group of scientists from several universities across the U.S. got together to work on the problem of which parts of the brain, if any specifically, are involved in analyzing and making moral judgments. To find out, or at least learn more, they devised three experiments meant to test the busyness of the brain, measured by blood flow, to certain regions, when presented with immoral situations. They have published the results of what they found in the journal Frontiers in Evolutionary Neuroscience.
The idea behind all three experiments was to present volunteers with material that is generally believed to be immoral while watching blood flow patterns in their brains using fMRI, as compared to what happens when moral or neutral material is viewed.

In the first study, volunteers were told that they would be engaging in a memory test. They were then shown a series of statements, followed by another series of statements after that. During the second series they were asked to press a button to indicate if the statement they were being shown had been among those shown in the first series. The statements shown were divided into four classes: pathogen related (non-sexually gross stuff), incestuous acts, nonsexual immoral acts and neutral acts.
In the second study, volunteers were shown three types of statements in random order: 50 examples describing acts that most people think of as immoral, 50 statements that most think of as pro-moral (morally good) and 50 statements that most people think of as neutral.
And finally, in the third study, volunteers were shown three types of pictures in random order: immoral, non-moral (negative without morality), and neutral.

After analyzing and normalizing the data, the researchers found that the left hemisphere of the brain showed increased blood flow in response to immoral stimuli throughout all three studies, while the right did not. No such pattern was found for the neutral or pro-moral tests. They also found that while each of the three tests tended to light up specific areas of the left hemisphere in the scanned images, there was also quite a bit of overlap between those participating in the three different studies.
The research team isn’t making any declarations regarding their results other than suggesting that it appears the left side of the brain appears to be more involved in immoral processing than the right. They also suggest the brain might have evolved to work this way to avoid duplication in processing and to increase efficiency.
© 2011 Medical Xpress
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20 Nov 2011

Space siblings at least two years apart to make them smarter

According to a new study by University of Notre Dame economist Kasey Buckles and graduate student Elizabeth Munnich, siblings spaced more than two years apart have higher reading and math scores than children born closer together. The positive academic effects of greater spacing between children were seen in older siblings, but not in younger ones, according to Buckles.

The study will be published in an upcoming issue of the Journal of Human Resources.

Using the 1979 National Longitudinal Survey of Youth (NLSY79), researchers sampled a nationally representative panel survey of 12,686 young people ages 14 to 22 in 1979, and their children. The study was designed to identify the causal effect of spacing on academic achievement.

“Our results indicate that longer gaps improve test scores for older children, and have no effect on the scores of younger children,” Buckles says. “This appears to be due in part to the fact that older children get more of their parents’ time when the younger sibling is not born until a few years later.”

Earlier research in other fields has focused mostly on the effects of small gaps (less than two years) between siblings on early outcomes such as birth weight and infant mortality. Buckles’ study investigates the effects of birth spacing on later-life academic performance as measured by the Peabody Individual Achievement Tests for math and reading.

“Parents often wonder whether there is an ideal spacing between children. Our results suggest that for at least one important outcome—academic achievement—greater spacing can improve outcomes for the older sibling.”
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18 Nov 2011

Women more likely to have 'broken heart syndrome'

A woman's heart breaks more easily than a man's
Females are seven to nine times more likely to suffer "broken heart syndrome," when sudden or prolonged stress like an emotional breakup or death causes overwhelming heart failure or heart attack-like symptoms, the first nationwide study of this finds. Usually patients recover with no lasting damage.
The classic case is "a woman who has just lost her husband," said Dr. Mariell Jessup, a University of Pennsylvania heart failure specialist who has treated many such cases.
Cyndy Bizon feared that was happening when her husband, Joel, suffered a massive heart attack in 2005. "May God work through your hands," the Maine woman told the surgeon as her husband was wheeled past her into the operating room. She later collapsed at a nurse's station from "broken heart syndrome" and wound up in coronary care with him. Both survived.

Japanese doctors first recognized this syndrome around 1990 and named it Takotsubo cardiomyopathy; tako tsubo are octopus traps that resemble the unusual pot-like shape of the stricken heart.
It happens when a big shock, even a good one like winning the lottery, triggers a rush of adrenaline and other stress hormones that cause the heart's main pumping chamber to balloon suddenly and not work right. Tests show dramatic changes in rhythm and blood substances typical of a heart attack, but no artery blockages that typically cause one. Most victims recover within weeks, but in rare cases it proves fatal.

Dr. Abhishek Deshmukh of the University of Arkansas had treated some of these cases.
"I was very curious why only women were having this," he said, so he did the first large study of the problem and reported results Wednesday at an American Heart Association conference in Florida.
Using a federal database with about 1,000 hospitals, Deshmukh found 6,229 cases in 2007. Only 671 involved men. After adjusting for high blood pressure, smoking and other factors that can affect heart problems, women seemed 7.5 times more likely to suffer the syndrome than men.

It was three times more common in women over 55 than in younger women. And women younger than 55 were 9.5 times more likely to suffer it than men of that age.
No one knows why, said Dr. Abhiram Prasad, a Mayo Clinic cardiologist who presented other research on this syndrome at the conference.
"It's the only cardiac condition where there's such a female preponderance," he said.
One theory is that hormones play a role. Another is that men have more adrenaline receptors on cells in their hearts than women do, "so maybe men are able to handle stress better" and the chemical surge it releases, Deshmukh said.

Bizon was 57 when her attack occurred; she's now 63. She and her husband are pharmacists and live in Scarborough, Maine.
"I remember grabbing the counter and a black curtain coming down before my eyes," she said in a telephone interview. Her attack was so severe that she went into full cardiac arrest and had to have her heart shocked back into a normal rhythm. Although most such attacks resolve without permanent damage, she later needed to have a defibrillator implanted.
About 1 percent of such cases prove fatal, the new study shows.
"In the old days, we'd say someone was scared to death," said Prasad.
About 10 percent of victims will have a second episode sometime in their lives. And although heart attacks happen more in winter, broken heart syndrome is more common in summer.
Heart Association, http://www.americanheart.org
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15 Nov 2011

Stem cells reverse heart damage

A new study says heart damage may be reversible with stem cell therapy without dangerous side effects.
On a June day in 2009, a 39-year-old man named Ken Milles lay on an exam table at Cedars-Sinai Medical Center in Los Angeles. A month earlier, he'd suffered a massive heart attack that destroyed nearly a third of his heart.

"The most difficult part was the uncertainty," he recalls. "Your heart is 30% damaged, and they tell you this could affect you the rest of your life." He was about to receive an infusion of stem cells, grown from cells taken from his own heart a few weeks earlier. No one had ever tried this before.

About three weeks later, in Kentucky, a patient named Mike Jones underwent a similar procedure at the University of Louisville's Jewish Hospital. Jones suffered from advanced heart failure, the result of a heart attack years earlier. Like Milles, he received an infusion of stem cells, grown from his own heart tissue.

"Once you reach this stage of heart disease, you don't get better," says Dr. Robert Bolli, who oversaw Jones' procedure, explaining what doctors have always believed and taught. "You can go down slowly, or go down quickly, but you're going to go down."

Conventional wisdom took a hit Monday, as Bolli's group and a team from Cedars-Sinai each reported that stem cell therapies were able to reverse heart damage, without dangerous side effects, at least in a small group of patients.

In Bolli's study, published in The Lancet, 16 patients with severe heart failure received a purified batch of cardiac stem cells. Within a year, their heart function markedly improved. The heart's pumping ability can be quantified through the "Left Ventricle Ejection Fraction," a measure of how much blood the heart pumps with each contraction. A patient with an LVEF of less than 40% is considered to suffer severe heart failure. When the study began, Bolli's patients had an average LVEF of 30.3%. Four months after receiving stem cells, it was 38.5%. Among seven patients who were followed for a full year, it improved to an astounding 42.5%. A control group of seven patients, given nothing but standard maintenance medications, showed no improvement at all.

"We were surprised by the magnitude of improvement," says Bolli, who says traditional therapies, such as placing a stent to physically widen the patient's artery, typically make a smaller difference. Prior to treatment, Mike Jones couldn't walk to the restroom without stopping for breath, says Bolli. "Now he can drive a tractor on his farm, even play basketball with his grandchildren. His life was transformed."

At Cedars-Sinai, 17 patients, including Milles, were given stem cells approximately six weeks after suffering a moderate to major heart attack. All had lost enough tissue to put them "at big risk" of future heart failure, according to Dr. Eduardo Marban, the director of the Cedars-Sinai Heart Institute, who developed the stem cell procedure used there.

The results were striking. Not only did scar tissue retreat -- shrinking 40% in Ken Milles, and between 30% and 47% in other test subjects -- but the patients actually generated new heart tissue. On average, the stem cell recipients grew the equivalent of 600 million new heart cells, according to Marban, who used MRI imaging to measure changes. By way of perspective, a major heart attack might kill off a billion cells.

"This is unprecedented, the first time anyone has grown living heart muscle," says Marban. "No one else has demonstrated that. It's very gratifying, especially when the conventional teaching has been that the damage is irreversible."

Perhaps even more important, no treated patient in either study suffered a significant health setback.

The twin findings are a boost to the notion that the heart contains the seeds of its own rebirth. For years, doctors believed that heart cells, once destroyed, were gone forever. But in a series of experiments, researchers including Bolli's collaborator, Dr. Piero Anversa, found that the heart contains a type of stem cell that can develop into either heart muscle or blood vessel components -- in essence, whatever the heart requires at a particular point in time. The problem for patients like Mike Jones or Ken Milles is that there simply aren't enough of these repair cells waiting around. The experimental treatments involve removing stem cells through a biopsy, and making millions of copies in a laboratory.

The Bolli/Anversa group and Marban's team both used cardiac stem cells, but Bolli and Anversa "purified" the CSCs, so that more than 90% of the infusion was actual stem cells. Marban, on the other hand, used a mixture of stem cells and other types of cells extracted from the patient's heart. "We've found that the mixture is more potent than any subtype we've been able to isolate," he says. He says the additional cells may help by providing a supportive environment for the stem cells to multiply.

Other scientists, including Dr. Douglas Losordo, have produced improvements in cardiac patients using stem cells derived from bone marrow. "The body contains cells that seem to be pre-programmed for repair," explains Losordo. "The consistent thing about all these approaches is that they're leveraging what seems to be the body's own repair mechanism."
This is unprecedented, the first time anyone has grown living heart muscle.
Dr. Eduardo Marban, Cedars-Sinai Heart Institute

Losordo praised the Lancet paper, and recalls the skepticism that met Anversa's initial claims, a decade ago, that there were stem cells in the adult heart. "Some scientists are always resistant to that type of novelty. You know the saying: First they ignore you, then they attack you and finally they imitate you."

Denis Buxton, who oversees stem cell research at the National Heart, Lung and Blood Institute at the National Institutes of Health, calls the new studies "a paradigm shift, harnessing the heart's own regenerative processes." But he says he would like to see more head-to-head comparisons to determine which type of cells are most beneficial.

Questions also remain about timing. Patients who suffer large heart attacks are prone to future damage, in part because the weakened heart tries to compensate by dilating -- swelling -- and by changing shape. In a vicious circle, the changes make the heart a less efficient pump, which leads to more overcompensation, and so on, until the end result is heart failure. Marban's study aimed to treat patients before they could develop heart failure in the first place.

In a third study released Monday, researchers treated patients with severe heart failure with stem cells derived from bone marrow. In a group of 60 patients, those receiving the treatment had fewer heart problems over the course of a year, as well as improved heart function.

A fourth study also used cells derived from bone marrow, but injected them into patients two to three weeks after a heart attack. Previous studies, with the cells given just days afterward, found a modest improvement in heart function. But Monday, the lead researcher, Dr. Dan Simon of UH Case Medical Center, reported that with the three-week delay, patients did not see the same benefit.

With other methods, there may be a larger window of opportunity. At least in initial studies, Losordo's bone marrow treatments helped some patients with long-standing heart problems. Bolli's Lancet paper suggests that CSCs, too, might help patients with advanced disease. "These patients had had heart failure for several years. They were a wreck!" says Bolli. "But we found their stem cells were still very competent." By that, he means the cells were still capable of multiplying and of turning into useful muscle and blood vessel walls.

Marban has an open mind on the timing issue. In fact, one patient from his control group e-mailed after the study was complete, saying he felt terrible and pleading for an infusion of stem cells. At Marban's request, the FDA granted special approval to treat him. "He had a very nice response. That was 14 months after his heart attack. Of course that's just one person, and we need bigger studies," says Marban.

For Ken Milles, the procedure itself wasn't painful, but it was unsettling. The biopsy to harvest the stem cells felt "weird," he recalls, as he felt the doctor poking around inside his heart. The infusion, a few weeks later, was harder. The procedure -- basically the same as an angioplasty -- involved stopping blood flow through the damaged artery for three minutes, while the stem cells were infused. "It felt exacfly like I was having a heart attack again," Milles remembers.

Milles had spent the first weeks after his heart attack just lying in bed re-watching his "Sopranos" DVDs, but within a week of the stem cell infusion, he says, "I was reinvigorated." Today he's back at work full time, as an accounting manager at a construction company. He's cut out fast food and shed 50 pounds. His wife and two teenage sons are thrilled.

Denis Buxton says the new papers could prove a milestone. "We don't have anything else to actually regenerate the heart. These stem cell therapies have the possibility of actually reversing damage."

Bolli says he'll have to temper his enthusiasm until he can duplicate the results in larger studies, definitive enough to get stem cell therapy approved as a standard treatment. "If a phase 3 study confirmed this, it would be the biggest advance in cardiology in my lifetime. We would possibly be curing heart failure. It would be a revolution."
(CNN) 
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