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Comment by Dr. Krishna Kumari Challa on December 9, 2015 at 12:52pm

The 2014 hypertension guidelines: implications for patients and practitioners in Asia
Hypertension is a global public health issue and a major cause of morbidity and mortality. Because of population growth and ageing, the number of people with uncontrolled hypertension rose from 600 million in 1980 to nearly 1 billion in 2008. Furthermore, the number of adults with hypertension in 2025 has also been predicted to increase by about 60% to a total of 1.56 billion. The prevalence of hypertension in most Asian countries has increased over the last 30 years and more dramatically in the last 10 years. Several factors contributed to such changes in Asia, but acculturation to Western lifestyle, modernisation and urbanisation are considered key contributing factors. There are some unique features in regards to cardiovascular risk in Asia. Specifically, Asian regions have disproportionately higher mortality and morbidity from stroke compared with Western countries. Furthermore, the relationship between blood pressure level and risk of stroke is stronger in Asia than in Western regions. Although evidence-based and qualified guidelines for hypertension diagnosis and management have been released recently from Europe and North America, the unique features of Asian patients with hypertension raise concerns in regards to the real clinical applicability of Western guidelines in Asian populations. Specifically, it is not yet clear to what extent the new blood pressure target proposed by Western guidelines for high risk and elderly hypertensive individuals apply to Asian populations.
European and North American blood pressure guidelines, issued last year, may actually boost the stroke risk if used for Asian patients, particularly the elderly, suggested an expert opinion published online in Heart Asia. High blood pressure is a key risk factor for stroke, but the link between the two is much stronger in Asians than it is in Europeans or North Americans, said the experts. The global number of people with poorly controlled high blood pressure has risen from 600 million in 1980 to almost 1 billion in 2008, and predicted to rise a further 60 percent to 1.56 billion by 2025. The prevalence of high blood pressure in Asian countries has risen sharply in the past 30 years, and particularly over the past decade, as a result of increasing urbanization and the adoption of a Western lifestyle. High blood pressure among Asian populations has unique features in terms of the response to drug treatment, risk of complications, and outcomes, say the authors. This leads to disproportionately high rates of death and ill health from stroke compared with Western populations. “Although evidence-based and qualified guidelines have been recently released from Europe and North America, the unique features of Asian hypertensive patients raise concerns on the real clinical applicability of these guidelines to Asian populations,” wrote the authors. The latest Western guidelines increased target blood pressure to 140/90 mmHg for patients at high risk of cardiovascular disease and renal failure, but this may be too high for Asian populations warn, the authors. Some Asian guidelines have recommended more stringent targets in these patients, they said. Treating high blood pressure in elderly Asian patients is particularly challenging, they said. And the threshold for systolic blood pressure recommended by Western guidelines could boost the risk of stroke in these patients. A threshold below 140/90 mmHg might be more appropriate, they suggest. “The paucity of data on the correct definition of the most appropriate [blood pressure] target in elderly patients, highlighted by the few available trials, should be perceived as a stimulus for future research in Asia, not as an argument for questioning the benefit of treatment,” the researchers wrote.
http://heartasia.bmj.com/content/7/2/21

Comment by Dr. Krishna Kumari Challa on December 8, 2015 at 5:55am

Rattan wood — the stems of a climbing palm that grows in South-East Asian and West African forests — could be the source of next-generation bone implants, with the first products planned for release in 2019.

Italian firm GreenBone announced last month that trials on sheep prove that its technology works. It found that rattan can be used to build a scaffold to support damaged bones by turning rattan into a material with the same strength, flexibility and porosity as bones.

“Rattan is totally biocompatible and absorbable, and structurally organised like natural bone... it induces bone regeneration.”

The chemical process that turns rattan into a bone-like material was developed by a team at the Institute of Science and Technology for Ceramics (Istec) of the Italian National Research Council. Through this process, plant materials such as lignin and cellulose are removed from pieces of rattan wood, which are then treated to create hydroxyapatite, the same mineral that makes up human bones.

“The advantages offered by rattan-derived bone-like material over other bone substitutes like ceramics, polymers and titanium are great,” says Anna Tampieri, a researcher with the Istec project and chief scientist at GreenBone “Unlike these solutions, rattan is totally biocompatible and absorbable, and structurally organised like natural bone. We also already had evidence that it induces bone regeneration. With time, it will completely fuse with the real bone.”

Bone replacement is crucial for treating various conditions when bones cannot self-repair. These include severe breaks, bone cancer and degenerative diseases such as osteoporosis.

Rattan bones could be especially important for replacing large chunks of bone — three centimetres or more — for which existing bone substitutes are unsuitable, the team found. In time, rattan grafts are replaced with newly formed bone without needing further surgery, making it a cheaper and less-invasive choice for long-term treatment, the researchers say.

Pilot studies by Tampieri’s team showed evidence of full integration with real bone and no signs of rattan bones being rejected or leading to infection.
http://www.scidev.net/global/r-d/news/rattan-wood-bone-implants-nea...

http://www.inbar.int/forest-femur

http://news.bbc.co.uk/2/hi/europe/8446637.stm

Comment by Dr. Krishna Kumari Challa on December 7, 2015 at 5:31am

How scientists are trying to protect coral reefs

Comment by Dr. Krishna Kumari Challa on December 4, 2015 at 7:36am

Event Horizon Telescope Reveals Magnetic Fields at Milky Way's Central Black Hole

The supermassive black holes at the centers of galaxies are more like cosmic engines, converting energy from infalling matter into intense radiation that can outshine the combined light from all surrounding stars. If the black hole is spinning, it can generate strong jets that blast across thousands of light-years and shape entire galaxies. These black hole engines are thought to be powered by magnetic fields. For the first time, astronomers have detected magnetic fields just outside the event horizon of the black hole at the center of our Milky Way galaxy.
A new study results appear in the Dec. 4th issue of the journal Science.
These magnetic fields have been predicted to exist, but no one has seen them before.
This feat was achieved using the Event Horizon Telescope (EHT) – a global network of radio telescopes that link together to function as one giant telescope the size of Earth. Since larger telescopes can provide greater detail, the EHT ultimately will resolve features as small as 15 micro-arcseconds. (An arcsecond is 1/3600 of a degree, and 15 micro-arcseconds is the angular equivalent of seeing a golf ball on the moon.)
The Event Horizon Telescope made observations at a wavelength of 1.3 mm. The team measured how that light is linearly polarized. On Earth, sunlight becomes linearly polarized by reflections, which is why sunglasses are polarized to block light and reduce glare. In the case of Sgr A*, polarized light is emitted by electrons spiraling around magnetic field lines. As a result, this light directly traces the structure of the magnetic field.

Sgr A* is surrounded by an accretion disk of material orbiting the black hole. The team found that magnetic fields in some regions near the black hole are disorderly, with jumbled loops and whorls resembling intertwined spaghetti. In contrast, other regions showed a much more organized pattern, possibly in the region where jets would be generated.

They also found that the magnetic fields fluctuated on short time scales of only 15 minutes or so.

“Once again, the galactic center is proving to be a more dynamic place than we might have guessed. Those magnetic fields are dancing all over the place.”

https://www.cfa.harvard.edu/news/2015-28

Comment by Dr. Krishna Kumari Challa on December 4, 2015 at 6:03am

Quantum entanglement of multiple particles! Heard it before?
A first-of-its-kind measurement has quantified a mysterious quantum bond shared by several particles rather than just two. The experiment, reported in the Dec. 3 Nature, brings physicists closer to understanding the true scope of this link, known as quantum entanglement.

Entanglement interweaves particles’ fates so that some of each particle’s properties, which are inherently uncertain according to quantum mechanics, are tied to those of its partners. Each particle essentially sacrifices its individuality to become part of an umbrella entangled state. While physicists have developed reliable methods for detecting entanglement between pairs of particles, the measurements get tricky when three or more particles are involved.

A team of quantum physicists from Harvard University measured a property called entanglement entropy, which quantifies the apparent randomness that comes with observing just a portion of an entangled whole. Markus Greiner and colleagues used lasers to create an optical cage with four compartments, each of which held a rubidium atom chilled to nearly absolute zero. The researchers could tweak the laser settings to adjust the height of the walls between compartments. If the walls were low enough, atoms could exploit their strange quantum ability to occupy multiple compartments at once. As the four atoms jumped around, they interacted and established a state of entanglement.

Greiner’s team created a pair of four-compartment systems and confirmed that they were identical using a technique developed for comparing photons. Then the researchers compared portions of the two cages — say, two of the four compartments where atoms could reside. The partial system of one cage differed from the corresponding partial system of the other cage. A difference between parts when the wholes are indistinguishable “only happens if there is entanglement within each system,” Greiner says.

While studying entangled particle pairs is interesting, the real world is dominated by entangled states that encompass much larger sets of particles. Analyzing particles in collections similar to those in Greiner’s experiment could help physicists understand the complex entanglement-rich interactions between electrons in superconductors, which conduct electrical current with no resistance.

http://www.nature.com/nature/journal/v528/n7580/full/nature15750.html

Comment by Dr. Krishna Kumari Challa on December 4, 2015 at 5:57am

Zika virus, which first appeared in Brazil in May, causes fever, rash, vomiting, red eyes and, in some cases, death. Brazilian health officials believe that a Zika infection during pregnancy harms growing fetuses. Pregnant women hit by the virus may be more likely to give birth to babies with the rare birth defect microcephaly, a congenital condition marked by a small head and abnormal brain development.

Over recent months, Brazilian health officials have noted an unusually high number of babies born with microcephaly. From 2010 to 2014, on average, 156 Brazilian babies were born with the birth defect each year. This year, health officials have already recorded 1,248 suspected cases of microcephaly. On November 28, government health officials reported that Zika virus had been found in tissue from a baby born with microcephaly, a find that links the birth defect to the virus.

Zika virus also has been documented in Africa, Southeast Asia and islands in the Pacific including the Cook Islands, French Polynesia and the Federated States of Micronesia. Because the Aedes mosquitoes that carry the virus live around the world, the virus will probably spread to previously unaffected areas.

https://flutrackers.com/forum/forum/emerging-diseases-other-health-...

Comment by Dr. Krishna Kumari Challa on December 3, 2015 at 6:04am

Comment by Dr. Krishna Kumari Challa on December 2, 2015 at 9:26am

Mysteries solved with the help of science and experts in the field...

Comment by Dr. Krishna Kumari Challa on December 2, 2015 at 8:33am

Non-Human Primates Harbor Diverse Mammalian and Avian Astroviruses Including Those Associated with Human Infections.
A new study of nearly 900 nonhuman primates in Bangladesh and Cambodia shows that macaques harbor diverse astroviruses, which can cause infectious gastroenteritis or diarrhea in humans. The research is the first to show evidence of human astroviruses in animals, and among the earliest to demonstrate that astroviruses can move between mammalian species, according to the report, published in PLOS Pathogens. “If you are a bat, you have bat astrovirus, but if you are a monkey, you could have everything,” said Dr. Lisa Jones-Engel, a research scientist at the University of Washington National Primate Research Primate Center and a co-author of the study. Astroviruses from a number of species, including human, bovine, bird, cow and dog, were detected in monkeys, “challenging the paradigm that AstV (astrovirus) infection is species-specific,” the authors wrote. It is still unknown whether these viruses are two-way and can be transmitted to humans. They did find evidence that, in monkeys, two species of astrovirus recombined.
Astroviruses are most commonly associated with diarrhea. They can also cause clinical diseases such as nephritis, hepatitis and encephalitis. However, astroviruses also can be asymptomatic, depending on the species. Currently, the only treatment is oral rehydration.
The researchers said more study is needed to determine if astrovirus infections in nonhuman primates are associated with clinical disease, or whether such infections are asymptomatic. They said none of monkeys sampled in the study appeared to have clinical disease (e.g., diarrhea) at the time of sampling.
http://journals.plos.org/plospathogens/article?id=10.1371/journal.p...

Comment by Dr. Krishna Kumari Challa on December 2, 2015 at 8:25am

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