8th Nov 2013, 12:11 PM #631
Re: Health Bulletin
US moves to ban artificial trans fats in food
The Food and Drug Administration on Thursday proposed measures that would all but eliminate artificial trans fats, the artery clogging substance that is a major contributor to heart disease in the United States, from the food supply.
Under the proposal, which is open for public comment for 60 days, the agency would declare that partially hydrogenated oils, the source of trans fats, were no longer "generally recognized as safe," a legal category that permits the use of salt and caffeine, for example. That means companies would have to prove scientifically that partially hydrogenated oils are safe to eat, a very high hurdle given that scientific literature overwhelmingly shows the contrary.
The Institute of Medicine has concluded that there is no safe level for consumption of artificial trans fats.
"That will make it a challenge, to be honest," said Michael R Taylor, deputy commissioner for foods at the FDA. Margaret A Hamburg, the agency's commissioner, said the rules could prevent 20,000 heart attacks and 7,000 deaths from heart disease each year.
The move concluded three decades of battles by public health advocates against artificial trans fats, which occur when liquid oil is treated with hydrogen gas and made solid. The long-lasting fats became popular in frying and baking and in household items like margarine, and were cheaper than animal fat, like butter.
But over the years, scientific evidence has shown they are worse than any other fat for health because they raise the levels of so-called bad cholesterol and can lower the levels of good cholesterol. In 2006, an FDA rule went into effect requiring that artificial trans fats be listed on food labels, a shift that prompted many large producers to eliminate them. A year earlier, New York City told restaurants to stop using artificial trans fats in cooking. Many major chains like McDonalds, found substitutes, and eliminated trans fats.
Those actions led to major advances in public health: Trans fat intake declined among Americans to about one gram a day in 2012, down from 4.6 grams in 2006. A report from the Centers for Disease Control and Prevention found that blood levels of trans fatty acids among white adults in the US declined by 58% from 2000 to 2009.
But the fats were not banned, and still lurk in many popular processed foods, such as microwave popcorn, certain desserts, frozen pizzas, margarines and coffee creamers. "The artery is still half clogged," said Thomas R Frieden, the director of the disease centers. "This is about preventing people from being exposed to a harmful chemical that most of the time they didn't even know was there."
He noted that artificial trans fats are required to be on the label only if there is more than half a gram per serving, a trace amount that can add up fast and lead to increased risk of heart attack.
Even as little as two or three grams of trans fat a day can increase the health risk, scientists say. NYT NEWS SERVICE
8th Nov 2013, 12:14 PM #632
Re: Health Bulletin
This onion won’t make you cry
Scientists have developed a new type of 'tearless' onions that produce less of the protein blamed for making eyes burn and tear up. The 'tearless' onions not only prevent eyes from burns and tears, but also fight against cardiovascular disease and weight gain, scientists say.
Researchers Colin C Eady and colleagues noted that the onion has a unique chemistry that leads to its tear-inducing effects when cut. Eady's team has developed a version of onions, which instead makes a sulphur compound similar to one found in cut garlic that may be the key to its cardiovascular benefits. Many people eat garlic cloves or take it as a nutritional supplement in pill form to reduce the clumping of platelets in the blood, which can lead to blood clots and clogged arteries.
Garlic also has been shown to reduce weight gain. They wanted to know whether the new onion might also have similar positive effects on health.
The scientists found that in lab tests, extract from the tearless onion significantly reduced platelet clumping, compared to regular onions or even garlic.
Other results showed that the new onion had about the same anti-inflammatory properties as the original. Also, preliminary testing in rats showed that the tearless onion could help control weight gain--more so than regular onions or garlic, according to the study published in The American Chemical Society's Journal of Agricultural and Food Chemistry.
A preliminary rat feeding trial indicated that the tearless onions may also play a key role in reducing weight gains, researchers said.
9th Nov 2013, 02:12 AM #633
Re: Health Bulletin
Fountain of youth? Scientists discover why wounds heal quicker for young people
The mystery of why wounds heal more quickly in the young compared to the elderly may soon be solved following the discovery of two of the genes involved in tissue regeneration.
Scientists believe that the findings will help to develop new drugs and treatments for faster wound-healing as well as shedding light on the ageing process itself, and what could amount to a genetic "fountain of youth".
Two teams of researchers found separate genes that accelerate tissue regeneration in laboratory mice. Both genes, which are also present in the human genome, are more active in young mice compared to older mice.
The scientists believe that the genes, called Lin28a and IMP1, are designed to be especially active during the foetal stages of development and are gradually turned off as an animal ages - which could explain why wounds take longer to heal in the elderly and how ageing occurs.
One of the teams, led by George Daley of the Boston Children's Hospital and Harvard Medical School, activated the Lin28a gene in adult mice and found that shaved fur on their backs grew back much faster than in ordinary adult mice where the gene had not be artificially boosted.
"It sounds like science fiction, but Lin28a could be part of a healing cocktail that gives adults the superior tissue repair seen in juvenile animals," said Dr Daley, whose study is published in the journal Cell.
Asked what the implications are for human health, Dr Daley said: "My strongest conclusion is that Lin28a, or drug manipulations that mimic the metabolic effects of Lin28a, enhances wound healing and tissue repair, and thus in the future might translate into improved healing of wounds after surgery or trauma in patients."
The study revealed that the Lin28a gene is responsible for a protein that binds to the key molecules of RNA involved in the metabolism of energy within the mitochondria, the "power packs" of the cells. The result is that when the gene is active, the cells are better and more efficient at repairing themselves - the activated genes also accelerated the repair of injuries.
Tissue regeneration is important in early foetal development and when damaged tissues need to be healed. A gradual loss of tissue regeneration and repair is one of the hallmarks of ageing so anything that could improve it could lead to anti-ageing treatments
"We were surprised that what was previously believed to be a mundane cellular 'housekeeping' function would be so important for tissue repair," said Shyh-Chang Ng of Harvard Medical School, the lead author of the Cell study.
"One of our experiments showed that bypassing Lin28a and directly activating mitochondrial metabolism with a small-molecule compound also had the effect of enhancing wound healing, suggesting that it could be possible to use drugs to promote tissue repair in humans."
The second gene, IMP1, also produces a protein that binds to the RNA molecules, but this time it promotes the self-renewal of key stem cells during foetal development, and also during tissue repair in later life, said Hao Zhu of the University of Texas in Dallas.
"This finding opens up an exciting possibility that metabolism could be modulated to improve tissue repair, whereby metabolic drugs could be employed to promote regeneration," Dr Zhu said.
9th Nov 2013, 01:14 PM #634
Re: Health Bulletin
Christian Medical College doctors use DNA sequencing to study mutated diabetes gene
For India, it means cutting edge research. For a person with diabetes, it could mean a world of change.
On Friday, doctors and scientists at Christian Medical College and Hospital in Vellore, announced new insights into the diagnosis of a less recognised problem in diabetes, more specifically, Maturity-Onset Diabetes of the Young (Mody), an inherited form of diabetes. They're insights that could radically change the course of treatment for a person with diabetes.
Dr Nihal Thomas, professor and head, department of endocrinology, diabetes & metabolism, CMC, who was part of the research team, said, "Type 1 is caused by the auto immune destruction of beta cells and usually manifests in childhood, while Type 2 diabetes is adult onset and is known to manifest after the age of 35." Doctors are now seeing diabetes in very young people, and while this is usually diagnosed as either Type 1 or 2, it may not be. "A clinician who does not know about Mody could start the patient on insulin when it may not be required," said Dr Thomas.
"For instance, patients may be taking insulin, but if they are found to have Mody 1 and 3, they only need oral tablets and there is no need for insulin. Some patients with Mody 2 may not even need any medical treatment if they learn to manage their diet and exercise," said Dr Thomas.
The doctors at CMC used next generation DNA sequencing technology for the first time in India to study 10 genes that are responsible for different types of Mody in a group of 70 patients, said Dr Thomas. The results were presented two weeks ago at the American Society of Human Genetics Conference in Boston, US, by Aaron Chapla, the primary scientist who set up the laboratory at CMC.
According to medical research, 13 different genes have been reported to cause Mody. "However, in India, prior to this, there have been reports of only two genes studied in a small set of clinically diagnosed patients with Mody," said Dr Thomas, citing high costs and non-availability of genetic diagnostic facilities, coupled with clinician unawareness as reasons.
Mody manifests itself before the age of 30, said Dr Thomas. And unlike in Type 1 and Type 2 diabetes, where multiple genes and lifestyle factors play a role, Mody is due to a mutation in a single gene and is reported to affect 1% to 2% of people with diabetes, he said. In India, there are around 70 million people with diabetes.
According to Chapla, studying three genes used to cost around Rs 50,000 and take 40 days per patient. But using the new technology, they can study 10 genes at the rate of eight patients a week. "We will be moving on from 10 to 12 Mody genes soon," said Dr Thomas.
"A result of the new testing is that we are picking up rarer ones. For instance, we have detected four cases of Mody 6. Across the world, there is published research of only five cases," said Dr Thomas. With the older technology, the pickup of abnormal Mody mutations was only 10%. With the new technology, and by studying a larger panel of genes, identification rates have more than doubled.
Since change in a single gene causes Mody, Dr Thomas said it could be passed on by affected parents to 50% of their children, whether male or female. "The new tests could also mean that other family members who are pre-disposed to diabetes can be counselled sooner," he said.
--Maturity-Onset Diabetes of the Young (Mody) is an inherited form of diabetes triggered by mutation in one gene
--Mody manifests itself before the age of 30
--It affects 1% to 2% of people with diabetes
--People with Mody may need only medication, and not insulin
--CMC used next generation DNA sequencing technology to study 10 genes responsible for different types of Mody in 70 patients
9th Nov 2013, 01:16 PM #635
Re: Health Bulletin
New bio patch can regrow bones
Indian-origin scientists have developed a revolutionary new bio patch which can regrow missing or damaged bones from within the body.
Researchers at the University of Iowa created the bio patch to regenerate bones by putting DNA into a nano-sized particle that delivers bone-producing instructions directly into cells.
The bone-regeneration kit relies on a collagen platform seeded with particles containing the genes needed for producing bone.
In experiments, the gene-encoding bio patch successfully regrew bone fully enough to cover skull wounds in test animals. It also stimulated new growth in human bone marrow stromal cells in lab experiments.
The study is novel in that the researchers directly delivered bone-producing instructions - using piece of DNA that encodes for a platelet-derived growth factor called PDGF-B - to existing bone cells in vivo, allowing those cells to produce the proteins that led to more bone production.
"We delivered the DNA to the cells, so that the cells produce the protein and that's how the protein is generated to enhance bone regeneration," said Aliasger Salem, co-corresponding author on the paper.
The researchers believe the patch could be used to rebuild bone in the gum area that serves as the concrete-like foundation for dental implants.
That prospect would be a "life-changing experience" for patients who need implants and don't have enough bone in the surrounding area, said Satheesh Elangovan, joint first author, as well as co-corresponding author, on the paper.
It also can be used to repair birth defects where there's missing bone around the head or face.
"We can make a scaffold in the actual shape and size of the defect site, and you'd get complete regeneration to match the shape of what should have been there," Elangovan said.
The team loaded the bio patch with synthetically created plasmids, each of which is outfitted with the genetic instructions for producing bone.
They then inserted the scaffold on to a 5 by 2mm missing area of skull in test animals. Four weeks later, the team compared the bio patch's effectiveness to inserting a scaffold with no plasmids or taking no action at all.
The plasmid-seeded bio patch grew 44-times more bone and soft tissue in the affected area than with the scaffold alone, and was 14-fold higher than the affected area.
"The most exciting part to me is that we were able to develop an efficacious, nonviral-based gene-delivery system for treating bone loss," said Sheetal D'mello, a graduate student in pharmacy and a joint first author on the paper.
The study was published in the journal Biomaterials.
10th Nov 2013, 03:57 PM #636
Re: Health Bulletin
Hot chocolate can keep brain healthy
A US study has suggested drinking two cups of hot chocolate a day may help elderly people to keep their brains healthy.
The study, published online in the American Academy of Neurology journal Neurology, involved 60 people with an average age of 73 who did not have dementia.
The participants drank two cups of hot cocoa per day for a month and did not consume any other chocolate during that time. These people were also given tests of memory and thinking skills as well as ultrasounds tests to measure the amount of blood flow to the brain.
"We're learning more about blood flow in the brain and its effect on thinking skills," said study author Farzaneh Sorond of the Harvard Medical School in Boston. "As different areas of the brain need more energy to complete their tasks, they also need greater blood flow."
"This relationship, called neurovascular coupling, may play an important role in diseases such as Alzheimer's," Sorond added.
The researchers found that 18 of the 60 participants, having impaired blood flow at the start of the study, saw an 8.3-percent improvement by the end of the study. There was no improvement for those who started out with regular blood flow.
The people with impaired blood flow also improved their times on a test of working memory, with scores dropping from 167 seconds at the beginning of the study to 116 seconds at the end, the researchers said. There was no change in times for people with regular blood flow.
However, Paul Rosenberg, of the Johns Hopkins School of Medicine in Baltimore, who wrote an editorial accompanying the study, said: "More work is needed to prove a link between cocoa, blood flow problems and cognitive decline."
"But this is an important first step that could guide future studies." Rosenberg added.
10th Nov 2013, 04:15 PM #637
Re: Health Bulletin
Mom's lifestyle link to baby's weak heart
Deficiency of vitamin D and calcium in Indian mothers is putting the lives of many infants at risk. Doctors warn that this micronutrient deficiency is being passed on to newborns, causing an increase in incidence of heart failures. Most hospitals report 3-4 such cases each month.
As a mineral, calcium helps in the contraction of muscles and blood clotting, in addition to building bones and keeping them healthy. Vitamin D helps in the absorption of calcium.
Pediatric cardiologists say a child needs 9-11 mg/dl calcium for a healthy heart. "If a child has less than the required amount of calcium in the body, it can impair the functioning of the heart. We get an alarming 2-3 such cases every month," said Dr Neeraj Aggarwal, pediatric cardiologist at Sir Ganga Ram Hospital. Infants with severe calcium deficiency have to be put on supplements-in the form of injections or syrup-for a period varying from two weeks to six months, say doctors.
Heart failure, which is triggered by calcium deficiency, was earlier seen in malnourished and pre-term babies mainly, Dr Aggarwal said. "But that's not true anymore. Most cases we get these days are of otherwise healthy babies from well-to-do families," he said.
According to Dr Viresh Mahajan, senior pediatric cardiologist at Max Hospital, Saket, infants are dependent on mother's milk for nutrition for the first six months.
"If the mother is critically deficient in micronutrients like vitamin D and calcium, the child may it is likely that the child may also suffer from the condition. There is need for compulsory screening of expecting mothers for such deficiencies of the essential micronutrients so that they are not transferred to the child," he said.
Depending on deficiency levels, Dr Mahajan said, a child may require calcium injections. "For example, a child whose heart is functioning with heart functioning at 15-20% of its capacity may require administering inotropic therapy and calcium injections for a few weeks," he added.
Health experts say that lack of exposure to sunlight (a major source of vitamin D) and milk-rich food (major source of calcium) is a common problem. "While many people do not exercise, others work in air-conditioned offices and move around in cars, thereby reducing exposure to sunlight. Due to this, vitamin D deficiency increases. Expecting mothers must undergo screening or blood test to assess the deficiency of important nutrientsand required supplementation to give birth to healthy children," said Dr Anita Saxena, senior pediatric cardiologist at AIIMS, adding that a greater number of instances of calcium deficiency-induced heart failure are being seen these days.
"Till a decade ago, doctors did not investigate this as a possible cause of heart failure. But now, with research showing a link between calcium deficiency and heart failure, diagnosis has gone up," she added.
11th Nov 2013, 01:24 PM #638
Re: Health Bulletin
Stress, booze worst stroke triggers
Stress and alcohol are the primary immediate triggers for stroke in Indian men but sexual activity could also set-off the life-threatening condition, a cross-sectional survey of patients conducted by AIIMS has found.
The survey, conducted on 290 stroke patients (210 men and 80 women) who visited the department of neurology from March 2012 to May 2013, showed that certain high-risk activities had triggered the stroke in 44% of them. Among men, this figure was higher at 48%.
A 'trigger' is the immediate cause that precipitates a stroke while 'risk factors' are lifestyle and health conditions that increase the chances of having a stroke in the long run.
"A small number of men, 5 out of 210 (2.4%), said they had sexual intercourse about two hours before the stroke," said Dr Ashish Sharma, who led the study. Previous studies have shown that sex induces transient increases in heart rate, blood pressure and adrenaline levels which might put pressure on brain tissues, precipitating a haemorrhagic stroke or bleeding in susceptible men.
Dr Sharma said none of the women patients reported sexual activity prior to the stroke. "It is difficult to analyse the cause and effect of sexual activity in precipitating stroke because many patients may not share the exact details," said another senior doctor.
Stroke, a condition traditionally associated with old age, is increasingly affecting young and middle-aged people. According to the study, trigger factors were mainly found in patients below 60 years of age. The presence of a trigger also made the stroke more severe, the study found.
Of the 48% of men who reported certain triggers for their stroke, 19% said they were nervous, distressed or scared in the week preceding the stroke due to stressful events. Another 15% said they had more than four standard drinks in the 24 hours preceding the stroke or equal to 15 standard drinks in the week before the event. About 9% said they suffered from infection in the preceding days.
Dr Kameshwar Prasad, professor and head of neurology department at AIIMS, said the findings could help predict when a stroke is most likely to occur in susceptible individuals, such as diabetics and hypertensive patients. "The study could help us develop a comprehensive stroke prevention programme which may include anger and stress management. In case of clinical infections, aggressive treatment of infections can be adopted to check the onset of stroke," said Dr Prasad.
With increase in the number of stroke cases in the recent past, particularly among youngsters, the neurology division of the institute conducted a cross-sectional survey on stroke patients to identify high-risk activities which precipitate the life-threatening situation.
A major new analysis from the Global and Regional Burden of Stroke in the 1990-2010 study, published in The Lancet, found there has been a sharp 25% increase in the number of stroke cases among people aged between 20 and 64 years over the past 20 years worldwide. Strokes in this age group now make up 31% of the total number of cases, compared to 25% before 1990. The overall amount of disability and illness and premature death caused by stroke is projected to be more than double worldwide by 2030.
11th Nov 2013, 03:40 PM #639
Re: Health Bulletin
Brain's decision-making algorithms decoded
Scientists have decoded the human brain's decision-making algorithms, deciphering precisely what happens in the organ when we make choices.
When faced with a choice, the brain retrieves specific traces of memories, rather than a generalised overview of past experiences, from its mental Rolodex, according to new brain-imaging research from the University of Texas at Austin.
Led by Michael Mack, a postdoctoral researcher in the departments of psychology and neuroscience, the study is the first to combine computer simulations with brain-imaging data to compare two different types of decision-making models.
In one model - exemplar - a decision is framed around concrete traces of memories, while in the other model - prototype - the decision is based on a generalised overview of all memories lumped into a specific category.
According to the findings, the exemplar model is more consistent with decision-making behaviour.
Researchers asked 20 respondents to sort various shapes into two categories.
During the task their brain activity was observed using functional magnetic resonance imaging (fMRI), allowing researchers to see how the respondents associate shapes with past memories.
With brain-imaging analysis, researchers found that the exemplar model accounted for the majority of participants' decisions.
The results show three different regions associated with the exemplar model were activated during the learning task: occipital (visual perception), parietal (sensory) and frontal cortex (attention).
While processing new information, the brain stores concrete traces of experiences, allowing it to make different kinds of decisions, such as categorisation information (is that a dog?), identification (is that John's dog?) and recall (when did I last see John's dog?).
"Imagine having a conversation with a friend about buying a new car. When you think of the category "car," you're likely to think of an abstract concept of a car, but not specific details. However, abstract categories are composed of memories from individual experiences. So when you imagine "car," the abstract mental picture is actually derived from experiences, such as your friend's white sedan or the red sports car you saw on the morning commute," Mack said.
"We flexibly memorise our experiences, and this allows us to use these memories for different kinds of decisions. By storing concrete traces of our experiences, we can make decisions about different types of cars and even specific past experiences in our life with the same memories," Mack said.
The study was published in the journal Current Biology.
11th Nov 2013, 03:54 PM #640
Re: Health Bulletin
'Kodo millet (varagu) helps keep diabetes under check'
Kodo millet (kodri), the wild cereal, has medicinal properties that can help diabetics and even the obese.
Research by professor M Daniel, former head of M S University's botany department, has revealed kodri, which yields white-husked grain, has a number of medicinal properties (including anti-diabetic and anti-rheumatic attributes), helps heal wounds and has a tranquilizing effect.
Kodri, which is cooked as rice, is cultivated in many countries for its grain and for fodder. In India, it is largely grown in parts of Gujarat, Maharashtra, Madhya Pradesh, Andhra Pradesh, Tamil Nadu, Odisha and Bihar.
"Since ancient times kodri is consumed as a food by diabetic patients, since traditionally it was believed it reduces sugar level," professor Daniel, who initiated the study at MSU and completed it at Dr Daniel's Laboratory, told TOI. "Recent experiments proved aqueous and ethanolic extracts of this grain produced a dose-dependent fall in fasting blood glucose (FBG) and a significant increase in serum insulin level. But the compounds responsible for reduction of sugar level were not known so far."
Through the research, the professor has isolated five anti-diabetic compounds — quercetin (the major one), ferulic acid, p-hydroxybenzoic acid, vanillic acid and syringic acid — from kodri and one chemical (quercetin) that prevents obesity.
"The alcoholic extract of kodri, which is responsible for the anti-diabetic property, is found to possess anti-diabetic compounds such as quercetin (a flavonol) and phenolic acids like vanillic acid, syringic acid, cis-ferulic acid, p-hydroxybenzoic acid and melilotic acid," he said. "The data on the phytochemicals of kodri substantiates the anti-diabetic property exhibited by this grain. Also, the presence of phospholipids, fibre contents and low oil content ... makes this grain a true nutraceutical."
The professor said kodri cultivation should be promoted in the country since unlike other cereals it grows even in gravelly or stony soils. "Kodri is also extremely drought- and salt-resistant and can be cultivated in saline areas and non-irrigational lands as well," he said.