Stanford chemists develop `ultra-sensitive test' for cancers

Malathy Iyer | TNN | Mar 24, 2016, 03.11 AM IST

Coming, super sensitive test to detect cancers, HIV (Getty Images)

It is usually said that early detection of cancer could lead to effective treatment, but a lot depends on the patient undergoing screening at the right time.
If a new method developed by Stanford University researchers clicks in a soon-to-be launched clinical trial, tests will soon become more sensitive in picking up cancer cells than existing tests.

"When a disease - whether a cancer or a virus like HIV - begins growing in the body, the immune system responds by producing antibodies. Fishing these antibodies or related biomarkers out of the blood is one way that scientists infer the presence of a disease. This involves designing a molecule that the biomarker will bind to, and which is adorned with an identifying "flag." Through a series of specialized chemical reactions, known as an immunoassay, researchers can isolate that flag, and the biomarker bound to it, to provide a proxy measurement of the disease," said a press release sent out by the university.

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Cancer vaccine?Communal Award

The new technique, developed in the lab of Carolyn Bertozzi, a professor of chemistry at Stanford, augments this standard procedure with powerful DNA screening technology. The scientists replaced the standard flag with a short strand of DNA, which can then be teased out of the sample using DNA isolation technologies that are far more sensitive than those possible for traditional antibody detections. ``The researchers tested their technique, with its signature DNA flag, against four commercially available, FDA-approved tests for a biomarker for thyroid cancer. It outperformed the sensitivity of all of them, by at least 800 times, and as much as 10,000 times. By detecting the biomarkers of disease at lower concentrations, physicians could theoretically catch diseases far earlier in their progression,'' it added.

Co-author Peter Robinson has been quoted as saying, "The thyroid cancer test has historically been a fairly challenging immunoassay, because it produces a lot of false positives and false negatives, so it wasn't clear if our test would have an advantage." He added that while the group hoped their test would be more sensitive, they were ``pleasantly surprised'' by the magnitude.

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Last Modified: Wed, Mar 23 2016. 06 12 PM IST

Ancient viruses lurking in our DNA: scientists

Scientists say one stretch of newfound DNA contains an intact, full genetic recipe for an entire virus

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PTI

Researchers confirmed 17 other pieces of virus DNA found in human genomes by other scientists in recent years. Photo: iStock

Washington: Our DNA is actually less human than previously thought, according to a new study that found 19 new pieces of non-human DNA left by viruses in our ancestors hundreds of thousands of years ago.
One stretch of newfound DNA, in about 50 of the 2,500 people studied, contains an intact, full genetic recipe for an entire virus, said researchers from University of Michigan and Tufts University.
Researchers do not know yet whether it can replicate or reproduce. But other studies of ancient virus DNA have shown it can affect the humans who carry it, they said.
In addition to finding these new stretches, researchers also confirmed 17 other pieces of virus DNA found in human genomes by other scientists in recent years.
The study looked at the entire span of DNA, or genome, from people from around the world, including a large number from Africa — where the ancestors of modern humans originated before migrating around the world.
Researchers used sophisticated techniques to compare key areas of each person’s genome to the “reference” human genome. The findings add to what science already knows about human endogenous retroviruses (HERVs).
HERVs is the name for the ancient infectious viruses that inserted a DNA-based copy of their own RNA genetic material into our ancestors’ genomes. They are part of the same type of virus that includes the modern human immunodeficiency virus, which causes AIDS.
Over generations, the virus-generated DNA kept getting copied and handed down when humans reproduced. That is how it ended up in our DNA today, researchers said.
About 8% of what we think of as our “human” DNA actually came from viruses.
In some cases, HERV sequences have been adopted by the human body to serve a useful purpose, such as one that helps pregnant women’s bodies build a cell layer around a developing foetus to protect it from toxins in the mother’s blood, they said.
The new HERVs are part of the family called HERV-K. The intact whole viral genome, or provirus, just found was on the X chromosome; it has been dubbed Xq21. It is only the second intact provirus found to be hiding in human DNA, researchers said.
“This one looks like it is capable of making infectious virus, which would be very exciting if true, as it would allow us to study a viral epidemic that took place long ago,” said John Coffin from Tufts University.
“This research provides important information necessary for understanding how retroviruses and humans have evolved together in relatively recent times,” Coffin said.
The findings were published in the journal PNAS.

PTI

Topics: Ancient virusesHuman DNAHuman GenomesHERVsProvirus

Kidney transplant now possible from any donor

Gina Kolata | NYT News Service | Mar 11, 2016, 03.22 AM IST

wo men, bound by a similar plight, underwent successful kidney transplants after their wives donated their kid... Read More

In the anguishing wait for a new kidney, tens of thousands of patients on waiting lists may never find a match because their immune systems will reject almost any transplanted organ. Now, in a revolutionary study, researchers have successfully altered patients' immune system to allow them to accept kidneys from an incompatible donor. Significantly, more of those patients were still alive after eight years than patients who had remained on waiting lists or received a kidney transplanted from a deceased donor.

The method, known as desensitisation, "has the potential to save many lives," said Dr Jeffery Berns, a kidney specialist and the president of the National Kidney Foundation, adding that the procedure could mean the difference between receiving a transplant and spending the rest of life on dialysis.

Researchers estimate about half of the 1,00,000 people in the United States on waiting lists for a kidney transplant have antibodies that will attack a transplanted organ, and about 20% are so sensitive that finding a compatible organ is all but impossible. In addition, said Dr Dorry Segev, the lead author of the study, an unknown number of people with kidney failure simply give up on the waiting lists and resign themselves to dialysis, a difficult and draining procedure that can pretty much take over a person's life.

Desensitisation involves first filtering the antibodies out of a patient's blood. The patient is then given an infusion of other antibodies to provide some protection while the immune system regenerates its own antibodies. For some reason — exactly why is not known — the person's regenerated antibodies are less likely to attack the new organ, Segev said. But if the person's regenerated natural antibodies are still a concern, the patient is treated with drugs that destroy any white blood cells that might make antibodies that would attack the new kidney.The process is expensive, costing $30,000, and uses drugs not approved for this purpose. The transplant costs about $100,000. But kidney specialists argue that desensitisation is cheaper in the long run than dialysis, which costs $70,000 a year for life. The process might be suitable for living-donor transplants of livers and lungs too, researchers said.

The desensitization procedure takes time — for some patients as long as two weeks — and is performed before the transplant operation, so patients must have a living donor.

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A huge breakthrough for so many suffering patients.Anthony

Clint Smith, one of the first patients who who went through desensitization, had progressive kidney disease and in 2004 they stopped functioning. His sister-in-law donated a kidney to him, but after six and a half years, it failed. He went on dialysis, it was keeping him alive, but it was not a life. Then a nurse suggested that he ask Johns Hopkins about its desensitisation studyand he qualified for the study. But he needed a donor and it came in the form of his wife's friend's husband.

That was four years ago, and Smith's new kidney is functioning and he is back to his normal active life.

admitted to the hospital with lung infection -dies-donates {infected}organs to 8 ?is this criminal to infect 8 more people with deadly infection??

Brain-dead Bengaluru youth lives on in 8 in New York

TNN | Mar 9, 2016, 08.59 AM IST

Bengaluru: The eyes, heart, pancreas, kidneys, oesophagus, liver and bone marrow of a Bengaluru youth have granted a new lease of life to at least eight persons in New York. This followed his family's decision to donate all his organs after he was declared brain-dead in Brooklyn Hospital Centre on Sunday.
Rajeev Naidu, 24, was admitted to the hospital with lung infection on February 21 and was undergoing treatment under the care of his roommates. Rajeev was pursuing masters in engineering from New York University in Washington Square South. He was a meritorious student and staunch follower of New Zealand cricketer Brendon McCullum.

"My parents and I haven't seen Rajeev since he fell ill in February . We never expected this. My husband Jayanth has gone to the US to bring his body home. We are proud of whatever he did while he lived and equally proud of him for promoting a greater cause by donating his organs," said his elder sister Kruthika Purushottam, a techie with HP. The family is expecting the body to arrive in Bengaluru by Thursday .

Last rites are likely to be performed on Friday . Rajeev, from Vidyanagar in Bommasandra, southeast Benglauru, completed BE in Computer Information Science from PESIT University in 2014. Rajeev worked in Dilip Material Hand ling Equipment, a local company in Bommasandra, for a year before taking admission for masters in NYU in 2015.

"Rajeev was an amazing person -kindhearted, helpful and always sport ed a smile. He would approach classmates, juniors and seniors to talk to them and help them. He was a great student and one of the top scorers in our university. Rajeev has made India proud by donating organs to those who needed them in US," said Tejaswini Reddy, a classmate from PESIT.

comment from a medic:-
 when a person dies of deadly infection of lungs it is criminal to donate his infected body parts to 8 people ;and they will also get the infection sure,and may die 
it is like donating the AIDS infected organs to others when AIDS patient dies