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Feb 23
Air pollution may speed up cognitive decline in women
Chronic exposure to particulate air pollution may accelerate cognitive decline in older women, researchers suggest.

In a large, prospective study led by a researcher at Rush University Medical Center, women who were exposed to higher levels of ambient particulate matter (PM) over the long term experienced more decline in their cognitive functioning over a four-year period.

Higher levels of long-term exposure to both coarse PM (PM2.5-10) and fine PM (PM2.5) were associated with significantly faster cognitive decline.

PM air pollution consists of small particles suspended in the air. Particles that are less than 2.5 microns in diameter, which is 1/30th the width of human hair, are called fine PM and particles larger than 2.5-10 microns is called coarse PM.

These associations were present at levels of PM exposure typical in many areas of the United States.

There are few recent studies that analyze air pollution and cognitive function in older adults, but this is the first study to examine change in cognitive function over a period of time and whether exposure to the size of particulate matter is important.

Jennifer Weuve, MPH., ScD, assistant professor of the Rush Institute of Healthy Aging and the principal investigator of the study, along with her colleagues, evaluated air pollution, both coarse and fine, in relation to cognitive decline in older women using a study population from the Nurses' Health Study Cognitive Cohort, which included 19,409 U.S. women ages 70 to 81 for a 14-year period going back as far as 1988.

"Our study explored chronic exposure to particulate air pollution in relation to decline in cognitive functioning among older women. Very is little known about the role of particulate matter exposure and its association with cognitive decline," said Weuve.

Exposure to particulate air pollution is associated with cardiovascular risk, which itself may play a role in causing or accelerating cognitive decline.

"Unlike other factors that may be involved in dementia such as diet and physical activity, air pollution is something we can intervene on as a society at large through policy, regulation and technology," said Weuve.

"Therefore, if our findings are confirmed in other research, air pollution reduction is a potential means for reducing the future population burden of age-related cognitive decline, and eventually, dementia," concluded Weuve.

Feb 23
Switching to diet drinks can help you shed 5% of your body weight in just six months
Ditching sugar-laden drinks and switching to either slim-line versions or water can help dieters shed up to 5 per cent of their body weight in just six months.

Researchers yesterday claimed that the simple substitution by those trying to lose weight will see them shift a minimum of 5lb.

Their study, due to appear in the American Journal of Clinical Nutrition, compared weight loss for 318 overweight or obese people.
Volunteers were divided into three groups - one group switched from calorie-laden beverages to diet soft drinks, the next switched to water, while the third group did not change their drinks and just received general information about healthy choices that could lead to weight loss.

Feb 22
The secret to long life? Starve yourself on alternate days to boost brain power and shed weight
Starving yourself on alternate days can make you live longer, according to scientists.

A group of Americans have said that fasting on and off can boost brain power and help to lose weight at the same time.

The National Institutes for Aging said their research was based on giving animals the bare minimum of calories required to keep them alive and results showed they lived up to twice as long.

The diet has since been tested on humans and appears to protect the heart, circulatory system and brain against age-related diseases like Alzheimer's.

'Dietery energy restriction extends lifespan and protects the brain and cardiovascular system against age-related disease,' said Mark Mattson, head of the laboratory of neurosciences at the NIA and professor of neuroscience at John Hopkins University in Baltimore.

Feb 22
Take tea to avoid heart problems, diabetes
While many of us may remain undecided about how much is too much for us to take tea in a day, researchers have now claimed that drinking three cups of tea a day could help us keep heart attacks as well as type 2 diabetes at bay.

A review shows that regular drinking of tea, with or without milk, can reduce the risk of heart problems by cutting levels of bad cholesterol and blood sugar, Daily Mail reported.

As per experts, the benefits of tea are largely due to the flavonoid content antioxidant ingredients that counteract cardiovascular disease.

One cup of tea provides 150-200mg of flavonoids and it is the best source of antioxidants in the diet

Drinking three or more cups of black tea a day protects against heart disease and two or more cups a day may protect against type 2 diabetes, a review in the journal Nutrition Bulletin found.

Nutritionist Carrie Ruxton, co-author of the latest review and a member of the industry backed Tea Advisory Panel (TAP), said: "There is far more to the nation's favourite drink than we realise.

"With its antioxidant flavonoids, black tea packs a powerful punch with many health benefits particularly for the heart. And recent studies show that the flavonoids work their magic whether or not we choose to add milk."

In addition, a 12-week study of 87 volunteers showed how drinking three cups of tea a day produced a significant improvement in various cardiovascular risk factors.

Flavonoids that are found in tea are said to assist in controlling inflammation, reducing excess blood clotting, promoting blood vessel function and also limiting furring up of the arteries.

Feb 21
One percent of human genes switched off
Scientists studying the human genome have found that each of us is carrying around 20 genes that have been completely inactivated, suggesting that not all switched-off genes are harmful to health.

A team at Britain's Wellcome Trust Sanger Institute is developing a new catalogue of so-called "loss-of-function" (LoF) gene variants to help identify new disease-causing mutations, and say their work will help scientists better understand the normal function of human genes.

Working as part of a larger study called the 1000 Genomes Project, the team developed a series of filters to identify common errors in the human genome, which maps the entire genetic code.

"The key questions we focused on for this study were how many of these LoF variants were real and how large a role might they play in human disease," says Daniel MacArthur of the Sanger Institute, who worked on the team.

The researchers looked at nearly 3000 possible LoF variants in the genomes of 185 people from Europe, East Asia and West Africa. Their findings were published today in the journal Science.
Zeroing in on how many

Loss of function variants are genetic changes that are predicted to severely disrupt the function of genes. Some are known to cause severe human diseases such as muscular dystrophy and cystic fibrosis.

Previous genome sequencing projects have suggested there are hundreds of these variants in the DNA of even perfectly healthy individuals, but researchers were not able to tell exactly how many.

In this study, the filters revealed that 56 per cent of the 3000 possible LoFs analysed were unlikely to seriously affect gene function.

But of the true LoF variants, 100 are typically found in the genome of each European, the researchers say, and 20 affect both copies of the gene - meaning they are likely to result in complete loss of gene function.

"This shows that at least 1 per cent of human genes can be shut down without causing serious disease," says Mark Gerstein, a professor of biomedical informatics from Yale University in the United States, who also worked on the study.

"We were able to use the differences between such 'LoF-tolerant' genes and known human disease genes to develop a way of predicting whether or not a newly discovered change in a gene is likely to be severely disease-causing."
Immediately useful

Chris Tyler-Smith, who led the team at the Sanger Institute, says the findings would prove immediately useful for current DNA sequencing studies in patients with particular diseases.

The results produced a list of more than 1000 LoF variants, he says, "and in most cases little or nothing is known about how these genes work or what they do.

"By studying the people carrying them in detail, we should get new insights into the function of many poorly known human genes."

Feb 21
Flu may boost Alzheimer's risk, research suggests
When we come down with the flu, we might think the worst is over after a week of a sore throat and body aches. But such viral infections may have lasting, unseen effects on the brain, emerging research suggests.

Viruses such as influenza and herpes may leave brain cells vulnerable to degeneration later in life, and increase the risk of developing diseases such as Alzheimer's and Parkinson's, research suggests. That's because these the viruses can enter the brain and trigger an immune response - inflammation - which can damage brain cells.

Viruses and other sources of inflammation "may be initiating factors in some of the most common neurological diseases," said Dr. Ole Isacson, professor of neurology at Harvard Medical School, who discussed the topic in an article published today (Feb. 15) in the journal Science Translational Medicine.

It's unlikely one bout of the flu will cause significant damage. But over a lifetime, injuries to cells accumulate, Isacson said, and along with environmental stresses, this can kill cells and the development of brain diseases. Variations in the number of infections we get may be the difference between a person developing Parkinson's disease at age 65 or at age 95, Isacson said.

It's possible that toning down the inflammation that occurs shortly after viral infection could reduce cell damage and the risk of subsequent brain disease, Isacson said. Isacson pointed to a 2011 study of 135,000 men and women found that those who took ibuprofen (a medication that can reduce inflammation) were 30 percent less likely to develop Parkinson's over a six year period compared to those who did not take the medication.

Brain infection

One of the earliest pieces of evidence for the virus-brain disease link comes from the 1918 influenza pandemic, according to Isacson's article. After that outbreak, there was a dramatic increase in cases of a disease called postencephalitic parkinsonism, which has many of the same symptoms as Parkinson's.

In a more rigorous test of the link, a 2009 study showed that mice injected with the H5N1 flu virus developed infections in cells in a brain region known to be significantly impacted by Parkinson's disease, Isacson said.

Research has also shown that infection with certain herpes viruses can increase the risk of Alzheimer's disease. And very rarely,encephalitis, or brain inflammation caused by viruses, can lead directly to an acute, but transient, form of Parkinson's disease.

But more often, viral infections in our brain are silent, Isacson said. We don't see the full impact of these infections until brain degeneration is substantial, he said.

Preventing disease

Several weeks after infection, inflammatory molecules known as cytokines reach a peak concentration, Isacson said. It's this "cytokine storm" that Isacson and his colleagues suspect is responsible for the brain cell damage associated with viral infections.

If researchers could find a way to block this peak from occurring, they might reduce the risk of certain neurological diseases, Isacson said.

In addition, researchers could also try to identify viruses that cause particularly severe cytokine storms, to better understand which infections pose the greatest risk to the brain, Isacson said.

The idea that immune system inflammation may influence the development of Alzheimer's disease and other neurological disorders is just one hypothesis out of many that are being investigated today, said Heather Snyder, senior associate director of medical and scientific relations at the Alzheimer's Association. More research is needed to understand what, if any, effect the immune system has on brain diseases, Snyder said.

Feb 20
Reducing salt in crisps without affecting the taste
Food scientists have found a way of measuring how we register the saltiness of crisps which could lead to new ways of producing healthier crisps - without losing any of the taste. The research by scientists at The University of Nottingham could lead to significant salt reduction in all snack foods.

The research, published on Thursday February 16 2012 in the Royal Society of Chemistry journal Food & Function, follows an investigation into how salt is released from crisps into the mouth.

Dr. Ian Fisk, a lecturer in the Division of Food Sciences, said: "The 'salt burst' from crisps is only released into the mouth 20 seconds after chewing begins. This means that in many cases the crisp may have already been swallowed before the majority of the salty taste is detected. Our aim is to develop a series of technologies that accelerate the delivery of salt to the tongue by moving the burst from 20 seconds to within the time that you normally chew and swallow. This would mean that less salt would be needed to get the same amount of taste.

Excess salt in the diet has been linked to high blood pressure and cardiovascular disease. The World Health Organization's recommendation for daily salt intake is just five grams. Many of us have twice this amount. The reduction of salt intake is now a major challenge for health authorities and the food industry.

Why is salt in our food?

Salt isn't just a flavor enhancer. Historically it has been added to enhance shelf life, improve functionality and control fermentation. Common foods including bread, meat products, breakfast cereals, cheese and popular snacks are among major dietary contributors to our salt intake.

There is now a clear need for the food industry to find ways of preserving these attributes while maintaining the consumer experience.

Crisps tasted under strict supervision

Salt release is complicated and the panel of 10 tasters were chosen for their ability to eat repeatedly 'under instruction'.

Working with Xing Tian, a Masters Project student, Dr. Fisk brought together the consumer panel of food tasters to chew crisps a prescribed number of times and hold them in their mouths for 60 seconds. The crisps were then swallowed as normal.

By taking tongue swabs and analysing the results on equipment capable of detecting sodium content they were able to monitor the salt levels as they peaked and troughed. Unlike other studies Dr. Fisk's research truly identified the moments of maximum intensity and maximum value.

Salt in crisps sits both on the surface and is embedded in the surface oil. So the salt has to be physically separated from the crisp bolus (chewed material), solubilized in the saliva and then moved to the salt receptors in the tongue for the brain to register the taste before being swallowed.

Dr. Fisk said: "After 20 seconds we detected a peak in saliva salt concentration. The panellists confirmed that they too detected an increase in salt perception at around this time."

Feb 20
Want to Lose Weight? Try Teamwork
A new study shows that people who shed at least 5% of their initial body weight during a weight loss competition were likely to be on the same teams. Those who said their teammates played a large role in their weight loss were more likely to lose a significant amount of weight.

The findings appear in Obesity.

Shows like The Biggest Loser often have team-, family-, or couples-based competitions that harness the power of peer influence when it comes to weight loss.

"People around us affect our health behaviors," says researcher Tricia Leahey, PhD. She is with The Miriam Hospital's Weight Control and Diabetes Research Center and is an assistant professor of psychiatry and human behavior at Alpert Medical School of Brown University in Providence, R.I.

This is true for healthy and unhealthy behaviors. "It could be quite beneficial if a bunch of friends that choose to lose weight make healthy food choices together, and hold each other accountable to those choices," she says.

Team members can motivate one another to stay the course. "If someone is doing really well, it could influence the whole group," Leahey says.

The findings are based on the results of the 2009 Shape Up Rhode Island campaign, a 12-week statewide, online weight loss competition. Participants competed against other teams for weight loss, physical activity, and the number of steps taken. The weight loss arm included 3,330 overweight or obese people on 987 teams. The teams had between five and 11 members.

Feb 18
Ray of hope for patients with end stage organ failure
Patients with end stage organ failure in the state can hope to prolong their life with the state government launching the Cadaver Transplant Programme. The programme paves the way for transplantation of vital organs harvested from brain-dead person in patients with chronic ailments.

The organs that can be transplanted include eyes, heart, lungs, liver, pancreas, kidneys, heart valves, skin, bones, bone marrow, connective tissues, middle ear, blood vessels and small intestine.

Though the government of India had passed the Transplantation of Human Organs Act in 1994, the state government had not framed rules to implement it in the state, which has the highest number of heart patients in the country and a large number of patients with liver and kidney related diseases.

The orders issued this week give legal backing for the organ transplantation. Issued under the Federal Act, the orders specify norms for determining brain death and procedures for removing and transplanting the organs.

The consent of relatives is a must for removing organs from brain dead persons and the person requiring organs needs to register with the health authorities. The order contains detailed guidelines for determining priority in making the organs available to patients. A provision would be incorporated soon for allowing donors to make donations to patients of their choice.

The government has set up a Core Committee for Cadaver Transplantation under the supervision of the Director of Medical Education to coordinate various functions related to the cadaver transplantation and a Cadaver Transplant Advisory Committee under the Health Secretary.

The Cadaver Transplant Programme was formulated on the basis of the report of an expert committee, which studied the implementation of the programme in the neighbouring states of Tamil Nadu and Andhra Pradesh.

Tamil Nadu has been a role model in cadaver transplantation. The state recorded a deceased donor rate of 1.3 per million as against 0.15 per million population in the country as a whole. Experts say that if the country can push the rate to the Tamil Nadu level it can easily meet the demand for organs. The current demand in the country for kidney transplants is 150,000; liver, 200,000 and heart, 150,000.

India now does only 3,000 kidney transplants and 500 liver transplants a year because there are not enough donors. Though 140, 000 lives are lost in the country through road accidents every year, the precious organs that could save the lives of many have been going waste.

Kerala too could meet the demand for vital organs to a great extent if a programme was in place to retrieve the organs of nearly 4000 road fatalities a year. The Cadaver Transplant Programme may help the state to tap this potential. However, experts say that simply laying the guidelines for cadaver transplant alone will not solve the problem. Though it simplifies the legal procedures there are social and ethical issues to be tackled.

In spite of high literacy people have not been coming forward to donate the organs. Health activists believe this is mainly because of ignorance, superstitious beliefs and religious restrictions. Private initiatives in the past have not been able to break these barriers. The Society for Organ Retrieval & Transplantation (SORT), one such initiative launched under the auspices of Indian Medical Association in 2000 could attract only 1500 donors in the last 12 years.

The society had to wait till 2004 for the first ever multi-organ transplantation. It was made possible by the members of the family of one Ramachandran Nair, who was declared brain dead following a road accident in June 2004. Three patients received the deceased's live and kidneys.

Sort has been organizing seminars on 'Religion and Organ Donation' involving religious heads to create awareness on organ donation. The Rotary Club of Trichur City has also been running a campaign involving doctors, NGOs, hospitals and others concerned to encourage organ donation. It has set up a body called RISORT (Rotary Initiated Society for Organ Retrieval and Transplantation) to popularise cadaver transplant in the state.

Feb 18
Smoking kicks out good bacteria from mouth
Smoking causes the body to turn against its own helpful bacteria, leaving smokers more vulnerable to disease, says an Indian-origin scientist.

They revealed that the mouth of a smoker is much more susceptible to invasion by harmful bacteria.

As a group, smokers suffer from higher rates of oral diseases -- especially gum disease -- than do nonsmokers, which is a challenge for dentists, according to Purnima Kumar, assistant professor of periodontology at Ohio State University.

"The smoker's mouth kicks out the good bacteria, and the pathogens are called in. So they're allowed to proliferate much more quickly than they would in a non-smoking environment," said Kumar

The results suggest that dentists may have to offer more aggressive treatment for smokers and would have good reason to suggest quitting smoking, Kumar said.

"A few hours after you're born, bacteria start forming communities called biofilms in your mouth. Your body learns to live with them, because for most people, healthy biofilms keep the bad bacteria away," stated Kumar.
She likens a healthy biofilm to a lush, green lawn of grass. "When you change the dynamics of what goes into the lawn, like too much water or too little fertilizer, you get some of the grass dying, and weeds moving in," she said.

For smokers, the "weeds" are problem bacteria known to cause disease.

In a new study, Kumar's team looked at how these bacterial ecosystems regrow after being wiped away. For 15 healthy nonsmokers and 15 healthy smokers, the researchers took samples of oral biofilms one, two, four and seven days after professional cleaning.
The researchers were looking for two things when they swabbed subjects' gums. First, they wanted to see which bacteria were present by analyzing DNA signatures found in dental plaque. They also monitored whether the subjects' bodies were treating the bacteria as a threat. If so, the swab would show higher levels of cytokines, compounds the body produces to fight infection.

The team found that for nonsmokers, bacterial communities regain a similar balance of species to the communities that were scraped away during cleaning. Disease-associated bacteria are largely absent, and low levels of cytokines show that the body is not treating the helpful biofilms as a threat.

"By contrast," said Kumar, "smokers start getting colonized by pathogens-bacteria that we know are harmful-within 24 hours. It takes longer for smokers to form a stable microbial community, and when they do, it's a pathogen-rich community."

Smokers also have higher levels of cytokines, indicating that the body is mounting defenses against infection. Clinically, this immune response takes the form of red, swollen gums-called gingivitis-that can lead to the irreversible bone loss of periodontitis.

In smokers, however, the body is not just trying to fight off harmful bacteria. The types of cytokines in smokers' gum swabs showed the researchers that smokers' bodies were treating even healthy bacteria as threatening.

Although they do not yet understand the mechanisms behind these results, Kumar and her team suspect that smoking is confusing the normal communication that goes on between healthy bacterial communities and their human hosts.

Practically speaking, these findings have clear implications for patient care, according to Kumar.

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