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Comment by Dr. Krishna Kumari Challa on October 16, 2015 at 6:39am

A person’s brain activity appears to be as unique as his or her fingerprints, a new Yale-led imaging study shows. These brain “connectivity profiles” alone allow researchers to identify individuals from the fMRI images of brain activity of more than 100 people, according to the study published Oct. 12 in the journal Nature Neuroscience.
Finn and co-first author Xilin Shen, under the direction of R. Todd Constable, professor of diagnostic radiology and neurosurgery at Yale, compiled fMRI data from 126 subjects who underwent six scan sessions over two days. Subjects performed different cognitive tasks during four of the sessions. In the other two, they simply rested. Researchers looked at activity in 268 brain regions: specifically, coordinated activity between pairs of regions. Highly coordinated activity implies two regions are functionally connected. Using the strength of these connections across the whole brain, the researchers were able to identify individuals from fMRI data alone, whether the subject was at rest or engaged in a task. They were also able to predict how subjects would perform on tasks.

Finn said she hopes that this ability might one day help clinicians predict or even treat neuropsychiatric diseases based on individual brain connectivity profiles.

Functional connectome fingerprinting: identifying individuals using patterns of brain connectivity
http://www.nature.com/neuro/journal/vaop/ncurrent/full/nn.4135.html

Comment by Dr. Krishna Kumari Challa on October 16, 2015 at 6:11am

Dietary supplements send 23,000 people, many of them children, to the emergency room in the U.S. each year, according to a new estimate reported in a new study based on a federal database of adverse events reported at 63 hospitals over a 10-year period., released online October 14 in the New England Journal of Medicine.
Just over 9% require hospitalization. Many patients report heart symptoms.
According to doctors who treated them the supplements include herbal products, amino acids, vitamins, minerals, and other complementary nutrition products hawked for a wide range of uses, often with little or no testing to back up claims.

The new study illustrates the idea that something that's 'natural' is not necessarily safe, and these products do not come without risk.
At these hospitals, the research team identified 3,667 emergency room visits linked to the supplements. That extrapolates to 23,005 adverse events nationwide each year, including an estimated 2,154 hospitalizations.

Unsupervised children under age 5 accounted for 21.6% of the visits.
Adults ages 20 to 34 made up an even bigger proportion of victims - 28%.

Weight-loss products accounted for an estimated 3,339 emergency room visits each year by women, nearly three times the number for men.

Among males, an estimated 567 visits were attributed to products designed for sexual enhancement and 368 were for body-building products. Comparable numbers for women were so small the researchers couldn't come up with a reliable estimate.

Heart symptoms were the chief complaint in 43% of people taking weight-loss products, 46% of patients taking energy products, 50% taking body-building products, and 37% taking sexual-enhancement products.

What's most concerning is the age of people coming in with cardiovascular complications or symptoms. They are in their 20s to 30s, which shows there are risks to these products.
Among older adults, swallowing problems caused nearly 40% of emergency department visits for supplement-related adverse events, with micronutrients implicated in more than 80% of these visits, the researchers said.

Comment by Dr. Krishna Kumari Challa on October 16, 2015 at 6:04am

Update on Ebola: 15th Oct., 2015

U.K. Ebola “Relapse” Case Takes Virus Specialists to Uncharted Waters according to Reuters

Scottish nurse Pauline Cafferkey is in critical condition following "totally unprecedented" return of symptoms
The case of Pauline Cafferkey, the first person known to have recovered from Ebola and then suffer an apparently life-threatening relapse, is taking scientists into uncharted territory.

The Scottish nurse's critically ill situation, described as "staggering" by one British virologist, signals just how complex and formidable a foe the Ebola virus may turn out to be now that scientists have the chance to study its survivors.

Previous studies and preliminary data from research in survivors of the vast West African outbreak have detected Ebola virus in semen, breast milk, vaginal secretions, spinal fluid and fluids around the eyes.

But scientific literature has never documented an Ebola relapse case before, meaning Cafferkey's is likely to generate great fear and anxiety for the 17,000 or so other Ebola survivors across West Africa.
This has never been observed before. Is this a one off? A very rare event? Or is this going to be quite common? The honest answer is we don't know!
Until researchers can study in detail and in large numbers of people the virus's long-term effects, each survivor, be they healthy or sickly, will be able to teach virologists more.
Preliminary data published this week has already forced a re-think on how long male survivors should be advised to abstain from sex or use condoms, with a study showing traces of Ebola can be found in semen of some men at least nine months after they first became ill.

Even if you don't have the virus in your bloodstream it can be hiding out. And we need to be aware of that because it's setting up the stage for potentially new outbreaks.

Comment by Dr. Krishna Kumari Challa on October 14, 2015 at 6:05am

Laos is facing again vaccine-derived polio, the World Health Organization said on 12th Oct., 2015.
The WHO said an 8-year-old boy died of the disease on Sept. 11, and genetic sequencing suggested the virus strain has been circulating in the area of Bolikhamxay province, which has low immunization rates, for more than two years.
A global vaccination campaign has all but beaten the wild polio virus, with only Pakistan and Afghanistan reporting cases of wild polio virus infection this year.

Specialists have warned that vaccine-derived cases - such as this one in Laos and previous ones in Ukraine and Mali - could hamper progress towards global eradication.
Ending polio requires eliminating both wild and vaccine-derived polio.

It added, however, that because of relatively limited travel to and from this area, and because of extra immunization campaigns planned in response, the risk of international spread of this polio strain from Laos is low.

Laos has been free of the wild polio virus since 1993, but poor immunization rates mean people are at risk of infection with strains of the virus that can mutate in sewage after being excreted by immunized children.

The risk of vaccine-derived polio cases can be avoided by switching from using live oral polio vaccines (OPV) - which are highly effective, cheap, easy to deliver but contain live virus, - to "inactivated" vaccines (IPV), which are not effective for fighting endemic disease but contain no live virus.

The WHO said the use of OPV is being scaled down in a phased manner as countries eliminate circulating wild polio virus strains.
- Reuters

Comment by Dr. Krishna Kumari Challa on October 11, 2015 at 11:57am

Comment by Dr. Krishna Kumari Challa on October 10, 2015 at 5:57am

Do you know that elephants rarely get cancer? And science may have found a part of the answer to this question 'why'!

According to a pair of papers independently published this week. Elephants have 20 copies of a gene called p53 (or, more properly, TP53), in their genome, where humans and other mammals have only one. The gene is known as a tumour suppressor, and it snaps to action when cells suffer DNA damage, churning out copies of its associated p53 protein and either repairing the damage or killing off the cell.

Joshua Schiffman, a paediatric oncologist and scientist at the University of Utah in Salt Lake City, first heard about Peto’s paradox three years ago at an evolution conference, when Carlo Maley, an evolutionary biologist now at Arizona State University in Tempe, revealed he had found multiple copies of TP53 in the African elephant's genome.

The researchers found that elephants produce extra copies of the p53 protein, and that elephant blood cells seem exquisitely sensitive to DNA damage from ionizing radiation. The animals' cells carry out a controlled self-destruction called apoptosis in response to DNA damage at much higher rates than do human cells. Schiffman suggests that, instead of repairing the DNA damage, compromised elephant cells have evolved to kill themselves to nip nascent tumours in the bud. “This is a brilliant solution to Peto’s paradox,” he says.

http://www.nature.com/news/how-elephants-avoid-cancer-1.18534

Schiffman and Lynch’s teams have now independently revealed their findings — Schiffman's in the Journal of the American Medical Association, and Lynch's in a paper posted to the bioRxiv.org preprint site, but which is in review at the journal eLife.

Comment by Dr. Krishna Kumari Challa on October 9, 2015 at 7:01am

Comment by Dr. Krishna Kumari Challa on October 8, 2015 at 5:49am

Researchers modify more than 60 genes with gene editing techniques in an effort to enable organ transplants from pigs into humans.
A steady supply of human organs for transplantation by growing them in pigs is what scientists always wanted to do. But concerns about rejection by the human immune system and infection by viruses embedded in the pig genome have put breaks on this research. Bymodifying more than 60 genes from pig embryos—ten times more than have been edited in any other animal—researchers believe they may have produced a suitable non-human organ donor now.
The work was presented on 5 October at a meeting of the US National Academy of Sciences (NAS) in Washington DC on human gene editing. Geneticist George Church of Harvard Medical School in Boston, Massachusetts, announced that he and colleagues had used the CRISPR/Cas9 gene-editing technology to inactivate 62 porcine endogenous retroviruses (PERVs) in pig embryos. These viruses are embedded in all pigs’ genomes and cannot be treated or neutralized. It is feared that they could cause disease in human transplant recipients.
Church’s group also modified more than 20 genes in a separate set of pig embryos, including genes that encode proteins that sit on the surface of pig cells and are known to trigger a human immune response or cause blood clotting. Church declined to reveal the exact genes, however, because the work is as yet unpublished. Eventually, pigs intended for organ transplants would need both these modifications and the PERV deletions.
Cutting multiple genes will also be useful for human therapies because many diseases with a genetic component involve more than one gene.
http://www.nature.com/news/gene-editing-record-smashed-in-pigs-1.18525

Comment by Dr. Krishna Kumari Challa on October 8, 2015 at 5:29am

DNA Repair Methods gets 2015 Chemistry Nobel Prize

Three scientists who found ways that cells fix damaged DNA—staving off cancer and other diseases—have won this year's prize
The coveted prize has gone to Tomas Lindahl from the Francis Crick Institute and Clare Hall Laboratory in Hertfordshire, England; Paul Modrich from the Howard Hughes Medical Institute and Duke University School of Medicine in North Carolina in the United States; and Aziz Sancar from the University of North Carolina in Chapel Hill, also in the U.S.
All the researchers, working independently over the last 40 years, described three different mechanisms that create errors in DNA—the molecule that controls cell behavior—and the different ways that chemical and biological processes fix many of these problems.

All forms of cancer start with DNA damage. If you do not have DNA repair, we would have a lot more cancer. That’s how important this is.
The understanding that we have of these mechanisms help us design drugs to repair all sorts of DNA errors. There are also several genetic diseases caused by the inability of cells to fix DNA properly, for instance, and work on the repair methods aids understanding of these ailments and how to treat them.
Scientists used to believe that DNA molecules were extremely stable. After all, they had to reliably transmit genetic information from generation down to generation. Then in the 1970s Lindahl demonstrated that the neat double helix and its components constantly decays. Every day, hundreds of those components, the DNA building block chemicals abbreviated as A, T, C, and G, get knocked out of their places. If the process continued unabated, the development of life on Earth would have been impossible. This insight led Lindahl to discover a series of enzymes and reactions, called base excision repair, which constantly works to fight this decay. The C building block, for instance, is repeatedly broken down into another molecule that should not be in DNA. The enzymes Lindahl found identify that broken molecule and rebuild it into a C.

Sancar found that cells use another technique to repair damage to DNA caused by ultraviolet light, the same thing that gives you a sunburn. This DNA fix is called nucleotide excision repair. People born with defects in this repair system will develop skin cancer if they are exposed to sunlight. Excision enzymes cut out the DNA lesions. The cell also uses this repair system to correct DNA damage people get after they are born, when they encounter mutagenic substances.

Finally, Modrich found out how a cell corrects errors that occur during a vital biological process: Cell division, when DNA is replicated. This copying process is supposed to produce identical strands of DNA but often there are stretches of the new stand that do not match up. The set of cellular chemicals that Modrich found, a complex called mismatch repair, scans the strands and fixes them, reducing the error frequency during replication by about a thousand times during each replication cycle.

Without all of these repair mechanisms, we would not be long-lived.

This year’s prize is about the cell’s toolbox for repairing DNA.

Comment by Dr. Krishna Kumari Challa on October 7, 2015 at 6:05am

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