Hindu26sep13 npcil, Westinghouse to sign ‘early’ n-agreement

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Two years back, Darrell Irvine of the Massachusetts Institute of Technology in the U.S., along with a team of other scientists, reported that a potent vaccine could be made by enclosing immunity-inducing substances in tiny capsules with several fatty layers.
Many germs, including HIV, gain entry into the body through moist tissue — the mucosa — that line the airways, alimentary canal, and the reproductive tract.
Dr. Irvine and colleagues have now demonstrated that such a nanocapsule vaccine can be administered in a needle-free manner at one mucosal site and produce immune protection at other mucosal surfaces as well.
The nanocapsules they tested in mice contained ovalbumin, an egg-white protein often used in immunology studies, along with two molecules to enhance the immune response. The ovalbumin played the part of an ‘antigen’, the bit of a pathogen that sets off the immune system’s alarm signals.
When the vaccine was administered to the airway of mice, immune cells patrolling the lining of the respiratory tract efficiently took in the nanocapsules and produced a strong immune response. Moreover, immune cells primed by the vaccine were detected in the gut and reproductive tract as well.
“We found that the nanocapsule vaccine promoted greater immunological memory at multiple mucosal tissue sites” than when the same vaccine components were given in solution, remarked Dr. Irvine in an email.
He and the other scientists also showed that mice immunised with an appropriate nanocapsule vaccine were much better protected when infected with the vaccinia virus.
“To date, strategies to enhance responses elicited by synthetic nanoparticle vaccines have largely focused on engineering the vaccine carrier itself, for example, to obtain optimal surface chemistry or particle size,” the scientists observed in their paper. “However, the site of vaccine administration may also play a critical role in the response to particulate vaccines.”
The safety and efficacy of their approach needed to be evaluated in a large-animal model closer to humans, such as monkeys, using relevant disease antigens, the scientists noted.
Besides HIV, this approach could be of interest for vaccines against many other mucosal pathogens, such as the human papillomavirus, herpes simplex virus, influenza and tuberculosis, said Dr. Irvine in his email.

At last, a Bill to control unethical practices in biomedical, health research

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Aarti Dhar

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Every biomedical and health research involving human participants, whether in conventional areas, or in new evolving specialised fields, will have to be conducted in accordance with the provisions of the proposed Biomedical and Health Research Regulation Bill, 2013.
Research on human subjects in the specified areas like assisted reproductive technology (ART); organ, tissue and cell therapy; genetic and genomic studies including techniques of genetic engineering and gene therapy; nano medicines; bio-banking; neurosciences, mental health studies and health related socio-cultural, economic and behavioural studies will all fall under the ambit of the proposed new law.
In the general areas of research, clinical studies involving human participants or material for development and evaluation of tools and strategies for promotion, prevention, amelioration and rehabilitation of diseases, or development of diagnostic tests or procedures, storage and use of biological materials; and scientific investigations required to understand processes which affect health, cause disease and influence human well-being; and translational study taking new leads will also be covered under the Biomedical Research Regulation Bill once it is approved by Parliament.
The purview
However, clinical trials involving systematic study of new drugs, medical devices, vaccines and cosmetics on human subjects will not fall under the purview of the proposed law.
In addition to this Bill, the existing laws including Drugs and Cosmetics Act, the Human Organ Transplantation Act, the Pre-Conception and Pre-Natal Diagnostic Techniques Act, the Medical Termination of Pregnancy Act and the Mental Health Act, too, will be applicable. The Bill focuses on the entitlements of a human participant during research making him eligible to be paid “due remuneration, compensation or reimbursement for the time lost, besides reimbursement of travelling and other incidental expenses incurred in connection with his participation in research.’’ The amount shall be decided by the ethics committee and shall not be such which can be considered as inducement for participation in research.
According to the Bill, the investigator and the institution shall take appropriate steps to safeguard the interest of special or vulnerable groups while the ethics committees shall ensure that individuals, groups or communities proposed to be subjected to research are selected by the investigator in such a way that the “burden and benefits’’ are equally distributed.
Human biological materials or data shall be used only after the express consent of the human participant and for the primary intended purpose approved by the ethics committee, and any request for secondary use of the human biological material or data shall be separately examined by the ethics committee. Important, according to the proposed Bill, there would be no bio-banking of the human biological material without consent of the human participant which should be governed by the specific principles of bio-banking.
Further, the Bill says that investigator shall maintain strict confidentiality of all research data which might lead to identification of the individual participant to avoid any consequent stigmatisation and discrimination unless he/she is under obligation to disclose the information to any official or the government department concerned under the provisions of any law.
“The confidentiality clause shall be incorporated in the information sheet while obtaining consent of the participant,’’ the Bill says.
On the informed consent, the Bill says in every biomedical and health research involving human participants, the investigator must obtain voluntary, documented, informed consent after being fully informed of his involvement in the research and also to withdraw the consent given earlier.
In case of an individual who is not capable of giving informed consent, for any reason, the consent of his legal guardian or legally authorised representative will have to be obtained.
“In case of research involving a group or community, legally acceptable representative or culturally appropriate authority of the group or community concerned may be contacted for permission. However, in no case shall a collective community agreement or the permission of a community leader or other authority be considered as a substitute for an individual consent.’’
The proposed Bill is expected to control unethical practices in biomedical and health research by making it mandatory to register all ethics committees in research institutions, colleges, universities and other organisations involved in research with the Biomedical and Health Research Authority. It specifies penalty for contravention of the provisions of the proposed legislation.

Unusual third Van Allen belt explained

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Vasudevan Mukunth

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The Van Allen radiation belts were discovered in 1958. They are gigantic donut-shaped belts of accelerated particles strung along the Earth’s magnetic field at 1,000-50,000 km above the surface. They consist of two distinct bands. The inner band consists of high-energy electrons and positive ions, and the outer band consists of high-energy electrons.
In February 2013, scientists reported that there was a third previously unobserved radiation, found lurking between the two original ones. Even more puzzling, this belt vanished after a month, leaving scientists wondering about its origins.
The answer may finally be here. Yuri Shprits, a researcher geophysicist at the University of California, Los Angeles, and his colleagues have performed calculations showing that the third belt was the result of an interaction between the outer belt and an injection of ions from a solar storm in September, 2012.
Shprits’s study, published in Nature Physics on September 22, also shows that the short-lived belt was composed entirely of ultra-relativistic electrons, i.e. travelling at close to the speed of light. The other belts have such electrons, too, but are not composed exclusively of them.
The team performed simulations with a model of the Earth’s radiation belts with respect to late August to early October, 2012.
They used information of space weather conditions as monitored and recorded by ground stations.
They showed that, during the solar storm, ions originating from a strong solar flare knocked out ultra-relativistic electrons from the outer belt almost to its inner edge. By the end, only a thin ring of ultra-relativistic electrons survived this.
“At ultra-relativistic energies, the physics to do with the wave-particle duality drives the radiation belts which allows for the formation of a vary narrow ring. This stayed unchanged for a whole month,” Shprits said in an email.
The simulations matched the observations from NASA’s Van Allen Probes mission, according some promise to this new theory of the mysterious ring.
Additionally, because so little is known about what accelerates particles in the radiation belts (a paper published in Science on August 30 suggests the cause is plasma waves originating from within the belts), Shprits’s work also sheds light on how those particles of different energies engage with conditions in space.
For instance, the electrons in the radiation belts have a wide range, from a “few hundred keV to multi-MeV,” Shprits wrote. 1 MeV, which stands for mega electron volt, is about the amount of energy corresponding to an electron accelerated to about 2,000 times its original mass.
“What we have discovered is that multi-MeV electrons form a new population that is driven by different physics and form very unusual structures in space,” he added.
He also cautioned that their ‘discovery’ was only the tip of the iceberg: “We still need to understand which physical processes are responsible for acceleration to ultra-relativistic energies.”
His and his team’s discovery could help engineers design better shielding for satellites that want to avoid radiation exposure to the Van Allen belts, as it could lead to anything from communication disruption to critical failure itself.

Oldest infectious disease of humans

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Ancient scourge:Mycobacterium tuberculosis (MTB) may well be the oldest pathogen to have infected humankind.— photo: AP

Ancient scourge:Mycobacterium tuberculosis (MTB) may well be the oldest pathogen to have infected humankind.— photo: AP
Modern humans (or homo sapiens) emerged out of the “hominid” group almost two million years ago, and began wandering out of Africa about 70,000 years ago to populate the world. How healthy were these people? What kind of illnesses affected them? Do we carry these afflictions to this date?
Questions such as these form the main research themes for a group of scientists who call themselves paleopathologists — paleo for ancient and pathology to define and describe the kind of illness. One such paleopathologist, Dr. Charlotte Roberts of Durham University, U.K. has written the book “The Archaeology of Disease”, where she argues that analysis of the DNA found in ancient human samples would help in understanding the origin and history of diseases that have affected us since antiquity.
Dr. Garth Sundem writes in his lucid essay “10 oldest known diseases” that in such studies, one should distinguish between diseases caused by external agencies (addiction, poisoning, infection) and age-dependent bodily dysfunctions (arthritis, epilepsy and such “conditions”) which are innate natural process of systemic malfunctions. The clue to zone in on the most ancient infection comes from both a study of bone abnormalities (seen in excavated bodies and mummies) and from analysis of all the DNA present in them. He points out that, contrary to the oft-quoted statement, dead men do tell tales.
Such a double analysis, plus information contained in ancient texts from across the world suggest the presence of ten diseases to be among the oldest to affect mankind. These are: tuberculosis (or TB), leprosy, cholera, smallpox, rabies, malaria, pneumonia, trachoma (chronic infection of the eyelid), influenza, measles and the black plaque. This list has been compiled by analysing information available from ancient texts and books such as the Vedas, the Bible, Greek history, oriental texts and oral history. The Rigveda (about 1500 BC) refers to TB and leprosy, the Egyptian “Ebers papyrus” (about 1500 BC) mentions leprosy, Thucydides of Greece (430 BC) mentions the plague, the Bible (Leviticcus 13.2) talks about leprosy and the Romans describe malaria. Aboriginal skeletons (800 BC) have shown skull lesions around the eyes, later suggested by circumstantial evidence as due to trachoma.
Sundem also refers to the analysis in Israel of the fossilized bones of a mother and child (estimated to be about 9000 years old) revealing the infection as due to TB, and also to a Turkish sample even older (50,000 years old!) again with the suggestion of TB affliction. It would thus seem that mycobacterium tuberculosis (MTB) may well be the oldest pathogen to have infected humankind.
MTB comes not as single strain but there are as many as 259 varieties that we know of today. Yet, DNA analysis of these strains has revealed not a great deal of diversity or heterogeneity, but very few mutations and nearly identical DNA sequences. Earlier work on such low level genetic variation, studied in 2005 by Dr. Veronique Vincent and colleagues at the Pasteur Institute, Paris, suggests that the present-day bacterium originated form a precursor or progenitor species — call it mycobacterium proto-tuberculosis , which could be as old as 3 million years. And the question is — when did this divergence from the single ancestor progenitor occur, how closely related in their DNA these 250 strains are and how sensitive or resistant each set of these strains is towards anti-tubercular drugs that we have today.
It is here that the recent paper by an international group led by Dr. Sebastien Gagneux of the Swiss Tropical and Public Health Institute, published in the 1 September 2013 issue of Nature Genetics is of value. The group analysed the DNA sequences of 259 TB strains from around the world, and showed that genetic diversity arose in them roughly around 70,000 years ago, concurrent with the outward migration from Africa of anatomically modern humans. When interviewed, Dr Gagneux pointed out that “the evolutionary path of humans and the TB bacteria show striking similarity. We see that diversity of MTB has increased markedly when human population expanded.”
In other words, what was dormant and restricted largely to the Rift Valley of Africa, where our far remote ancestors lived, became active and diverse as they started living in communities and passed on infection from person to person. And contrary to conventional wisdom, rather than getting infected from domesticated animals, we may even have passed on the TB germ to our pet animals.

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