today's health articles-21st dec, 2010

Heavy exercise can help you live longer

IANS, Dec 21, 2010, 12.00am IST
Heavy exercise could be the secret to living longer, scientists claim. 

A study found that strenuous physical activity - like running a marathon can stop cells dying and keep bodies healthy till old age, reports express.co.uk .

Scientists hope that finding a drug to slow cell death - a process called apoptosis could help prevent people from ageing completely.

They discovered that apoptosis is stopped after heavy exercise. Their findings suggest this is because a gene called sirtuin - an anti-ageing protein looks after the cells during exercise.

This could mean that certain cells which cannot normally re-generate, such as skeletal muscular cells, can be protected by exercise.

The scientists studied amateur athletes after a 26-mile run, looking at cells in the blood that are critical for helping the immune system to fight infection.

They found that the balance between the slowing of cell death changed after the race.

Matteo Russo, one of the researchers, said: "Sirtuins are genes that alone can increase the survival rates of mammals, including may be man".

"They are very important because they are involved in the link in maintaining tissues which usually don't proliferate. We hope that this kind of single link can be useful for successful ageing, which is very important," he added.


Homes are home to infections
Household is where the maximum number of infections are born, a global hygiene council (GHC) study report said Thursday. 

"Nearly 90 per cent of infections originate in our households because of unhygienic conditions," said Narendra Saini, representative of the GHC. 

The main source of bacterial and viral infections are door handles, refrigerators, towels and uncleaned floors at homes. 

"It is not the dirt that we clean, it is the absence of germs that makes a surface hygienic and infection-free. The method of cleaning is much more important than the frequency of cleaning," Saini added. 

The study, conducted in nine countries across the globe, was a joint venture of GHC and Reckitt Benckiser. 

"Diseases such as swine flu can be prevented if proper hygiene is maintained. But a lot of awareness is required to tell people about the ways of maintaining hygiene," said V.K. Monga, chairman of municipal health committee in Delhi. 

"Civic bodies and GHC are working on awareness creation programmes in select schools of Delhi. Our target group for the programme are children," Monga added. 

According to the GHC study, nearly 60 per cent of diseases in India are communicable in nature. 

Abnormal rhythms behind sudden death

ANI, Dec 21, 2010, 06.46pm IST

An international team of scientists has identified DNA sequence variations linked with the heart's electrical rhythm in several surprising regions among 22 locations across the human genome. 

Among the notable discoveries were variations in two side-by-side genes that regulate electrically charged particles to produce signals that start contraction of the heart and register as pulsing waves seen on heart monitors.

One of the genes, named SCN5A, was known to be involved in controlling how signals start from specialized muscle cells and travel across the heart to cause its rhythmic contractions. Its neighbour, SCN10A, previously was an unsuspected player in cardiac electrical activity.

The study's genome-wide hunt focused on the QRS interval, a measure of electrical depolarization in the main lower pumping chambers of the heart (ventricles), easily detectable with a simple EKG machine.

A prolonged QRS interval suggests a diseased ventricular conduction system and has been associated with increased risk for sudden cardiac death, among other heart disorders.

Fifteen genome-wide association or so-called GWAS studies among healthy American and European populations who had EKGs were combined for large-scale meta-analysis.

Each GWAS reported what effects were observed at which locations in a scan of 2.5 million single nucleotide polymorphisms (SNPs) throughout the genome. Pronounced snips, SNPs are sites where a single letter in the DNA code is variable. Study subjects whose EKGs showed prolonged QRS intervals had SNPs in common with each other.

"The size of the study really gave us the power to identify many genes not previously suspected to play a role in heart conduction," said Dan Arking of the Johns Hopkins University.

To further investigate one of the 22 regions deemed significant, team members used mouse hearts to find where in the heart the ion channel protein products of the SCN10A gene form, locating an abundance of them in the fibers that conduct electrical signals.

Next, the researchers treated mice with a drug that blocked the function of the ion channels produced by the SCN10A gene, and used EKGs to show that the QRS duration was extended in these animals.

"These genes potentially could be very useful for identifying individuals for whom adverse drug reactions may cause life threatening cardiac events," said Arking.

The findings were reported in the Nature Genetics .