Sunday, July 29, 2012
Elizabeth Blackburn, an alumna of Darwin College and a recipient of an Honorary Doctorate of Science from the University earlier this year, has been awarded the Nobel Prize in medicine. Professor Blackburn, along with Carol Greider and Jack Szostak, has been awarded the 2009 Nobel Prize for her research on telomerase, an enzyme she discovered in 1985 with her then PhD student Dr Greider. Telomerase, which adds DNA to the ends of chromosomes in cells, plays a key role in cancer development and has been the focus of much cancer research since its discovery.
Scientists have identified a diabetes drug which halves the mortality rate of a deadly infectious disease found throughout Southeast Asia and Northern Australia. Melioidosis, caused by a soil dwelling bacterium (Burkholderia pseudomallei) that is present in certain regions of the world, results in severe infections include bloodstream infections and pneumonia. Death results in up to 40% of affected individuals despite antibiotic treatment. New research by a multinational team from the United Kingdom, Thailand, Singapore and The Netherlands, however, has found that people taking the diabetes drug glibenclamide (called glyburide in the US) have half the mortality of other patients with melioidosis.
A collaborative project between physicists, oncologists and computer scientists at Oxford and Cambridge Universities, launched last month, will develop improved tools for the planning of high precision radiotherapy. Accel-RT will also help overcome time constraints that currently limit the use of complex radiotherapy treatment. Radiation therapy (radiotherapy) is an essential part of cancer treatment and is used in the treatment of 40 per cent of all patients who are cured of their disease. All radiotherapy treatments work by the application of ionising radiation to malignant cells in tumours. The free radicals released by this process damage the DNA of the exposed tissue, killing off the cancerous cells. By targeting the radiation to the tumour, the damage to surrounding healthy tissue is minimised.
The study published today by University of Cambridge scientists working with colleagues in India and the USA is the first to visualise the movement of gases at one million degrees in coronal loops – solar structures that are rooted at both ends and extend out from active regions of the Sun. Active regions are the ‘cradle’ for explosive energy releases such as solar flares and coronal mass ejections (CMEs). The observation will help scientists understand what is considered to be one of the most challenging issues in astrophysics – how solar structures are heated and maintained in the upper solar atmosphere. Extreme solar activity can lead to severe space storms that interfere with satellite communications and damage electric power transmission grids on Earth. Solar activity is cyclical, with the next maximum forecast to occur around May 2013, and severe space weather is now listed very high on the UK’s 2012 National Risk Register of Civil Emergencies. Based on observations from the Hinode satellite (a joint Japanese, NASA, European Space Agency and UK project), the new findings provide the first evidence of plasma upflows travelling at around 20 km per second in the one million degree active region loops. The scientists suggest that the upflow of gases is probably the result of “impulsive heating” close to the footpoint regions of the loops. “Active regions are now occurring frequently across the Sun. We have a really great opportunity to study them with solar spacecraft, such as Hinode and the Solar Dynamics Observatory (SDO),” said co-author Dr Helen Mason from the University of Cambridge’s Department of Applied Mathematics and Theoretical Physics. “Probing the heating of the Sun’s active region loops can help us to better understand the physical mechanisms for more energetic events which can impinge on the Earth’s environment.” Previous ultraviolet images of the Sun taken by NASA’s SDO have shown large loops of hot gas guided by the Sun’s magnetic field and rooted near sunspots. Despite such remarkable developments in the observations and theory of active regions over the past few decades, the question remained as to how solar plasma is heated and rises up into the loops in the first place. Now, the new research provides the first visualisation of plasma flow by showing the movement of gases within the loop as ‘blueshifts’ in diagnostic images using the extreme ultraviolet imaging spectrometer (EIS) on the Hinode satellite. Spectral lines produced by the spectrometer act like ‘fingerprints’ or the ‘bar code’ in a supermarket – the lines identify the multitude of elements and ions within the loop and shifts in the position of the lines provide information on the motion of the plasma. Although the Sun is composed mainly of hydrogen and helium, there are also other trace elements, such as oxygen and iron, in the hot ionised gas within the loops. The scientists suggest that the gas movement is caused by a process of “chromospheric evaporation” in which “impulsive heating” on a small scale can result in the heating of the solar active regions but on a larger scale can lead to huge explosions, such as solar flares or coronal mass ejections. “It is believed that magnetic energy builds up in an active region as the magnetic field becomes distorted, for example by motions below the surface of the Sun dragging the magnetic fields around,” explained Mason, whose research is partially funded by the UK’s Science and Technology Facilities Council (STFC). “Sometimes magnetic flux can emerge or submerge and affect the overlying magnetic field. We believe that solar plasma surges upwards when impulsive heating results from magnetic reconnection which occurs either in the loops or close to the Sun’s surface. These disruptions are sometimes relatively gentle but can also be catastrophic.” Commenting on the newly published study, Professor Richard Harrison MBE, Head of Space Physics and Chief Scientist at the STFC Rutherford Appleton Laboratory, said: “The Sun governs the environment in which we live and it is the so-called solar active regions that drive extreme conditions leading to the explosive flares and the huge eruptions; understanding these active regions is absolutely critical for the study of what we now call space weather. The work published by in this paper is a key element of that work, applying innovative analyses to the observations from the UK-led Hinode/EIS instrument.” The researchers hope that a better understanding of active regions might one day help scientists to identify the magnetic field structures that lead to explosive solar energy releases and use this as a means for predicting when such events will occur. The study is published today in Astrophysical Journal Letters.
Evidence of a community of prehistoric artists and craftspeople who “invented” ceramics during the last Ice Age – thousands of years before pottery became commonplace – has been found in modern-day Croatia. The finds consist of 36 fragments, most of them apparently the broken-off remnants of modelled animals, and come from a site called Vela Spila on the Adriatic coast. Archaeologists believe that they were the products of an artistic culture which sprang up in the region about 17,500 years ago. Their ceramic art flourished for about 2,500 years, but then disappeared. The study, which is published in the journal PLoS ONE, adds to a rapidly-changing set of views about when humans first developed the ability to make ceramics and pottery. Most histories of the technology begin with the more settled cultures of the Neolithic era, which began about 10,000 years ago. Now it is becoming clear that the story was much more complex. Over thousands of years, ceramics were invented, lost, reinvented and lost again. The earliest producers did not make crockery, but seem to have had more artistic inclinations. The Vela Spila finds have been the subject of intensive investigation by researchers at the University of Cambridge and colleagues in Croatia since 2010. Their report, published this week, suggests that although earlier ceramic remnants have been found elsewhere, they had no connection with the site, where the ability to make these artefacts appears to have been independently rediscovered by the people who lived there. “It is extremely unusual to find ceramic art this early in prehistory,” Dr. Preston Miracle, from the University of Cambridge, said. “The finds at Vela Spila seem to represent the first evidence of Palaeolithic ceramic art at the end of the last Ice Age. They appear to have been developed independently of anything that had come before. We are starting to see that several distinct Palaeolithic societies made art from ceramic materials long before the Neolithic era, when ceramics became more common and were usually used for more functional purposes.” Vela Spila is a large, limestone cave on Korčula Island, in the central Dalmatian archipelago. Excavations have taken place there sporadically since 1951, and there is evidence of occupation on the site during the Upper Palaeolithic period, roughly 20,000 years ago, through to the Bronze Age about 3,000 years ago. The first ceramic finds were made back in 2001. Initially they were almost overlooked, because it is so unusual to find ceramic in the Upper Palaeolithic record. As more ceramic emerged, however, examples were set aside for careful analysis. Researchers meticulously checked the collection for tell-tale evidence of modelling on the artefacts which would confirm that they had been made by a human hand. In all, 36 cases were identified. Broadly, the collection belongs to a material culture known as “Epigravettian” which spanned 12,000 years, but radiocarbon dating has allowed scholars to pin down the Vela Spila ceramic collection to a much narrower period, between 17,500 and 15,000 years ago. Those which can be identified appear to be fragments of modelled animals. The ceramics were clearly made with care and attention by real craftspeople who knew what they were doing. One of the better-preserved items, which seems to be the torso and foreleg of a horse or deer, shows that the creator deliberately minimised the number of joins in the model, perhaps to give it structural strength. They were also marked with incisions, grooves, and punctured holes, using various tools, probably made from bone or stone. Finger marks can still be seen where the objects were handled while the ceramic paste was wet. As well as being the first and only evidence of ceramic, figurative art in south-eastern Europe during the Upper Palaeolithic, the collection’s size, range and complexity suggests that Vela Spila was the heart of a flourishing and distinctive artistic tradition. Although the finds bear some similarities with ceramics discovered in the Czech Republic, which date back a further 10,000 years, there are enough structural and stylistic differences – as well as separation by a huge gulf in time – to suggest no continuity between the two.
Shift work can dramatically increase the risk of heart attacks and strokes, warn researchers. A study of two million people found shift workers are almost 25 per cent more likely to suffer. Night shift workers run the highest risk of 41 per cent, says a study published on the British Medical Journal website People working shifts also have higher levels of unhealthy behaviours such as eating junk food, sleeping badly and not exercising, which are linked to heart problems. But researchers said they took this into account - and the excess risks remained. The latest study is the biggest analysis of shift work and likelihood of vascular problems including heart attacks, strokes and angina. Shift work has long been known to disrupt the body clock and be linked to high blood pressure, high cholesterol and diabetes, but the overall impact on cardiovascular health has been unclear. A team of international researchers analysed the results of 34 studies involving 2,011,935 people to investigate whether shift work was associated with major vascular events. Shift work was defined as evening shifts, irregular or unspecified shifts, mixed schedules, night shifts and rotating shifts, and the studies also contained day workers or the general population for comparison. Altogether 17,359 had some kind of coronary event, 6,598 had heart attacks and 1,854 had ischaemic strokes caused by lack of blood to the brain. These events were more common among shift workers than other people. Shift work was associated with a 23 per cent increased risk of heart attack, 24 per cent rise in coronary events and five per cent extra strokes. These risks remained consistent even after adjusting for factors such as study quality, socioeconomic status and unhealthy behaviours in shift workers. Night shifts were linked with the steepest increase in risk of 41 per cent for coronary events. However, shift work was not associated with increased death rates from any cause. Daniel Hackam, Clinical Pharmacologist, Stroke Prevention & Atherosclerosis Research Centre (SPARC), London, Ontario, Canada, said the relative risks might appear modest, but millions of people do shift work which means the overall risks are high. He said screening programmes could help identify and treat risk factors, such as high blood pressure and cholesterol levels. ‘Shift workers should be educated about cardiovascular symptoms in an effort to forestall or avert the earliest clinical manifestations of disease’ he added. There has been mounting evidence that night shift working might boost cancer risk because of the disruption to the body clock and hormone production. Previous research found a link between night shifts and increased risk of breast cancer in women. In 2007 the International Agency for Research on Cancer concluded that shift work was ‘probably carcinogenic’.
Yoga may help stroke survivors improve their balance, according to a new study. Researchers found group yoga can improve balance in stroke survivors who no longer receive rehabilitative care. In a pilot study, scientists tested the potential benefits of yoga among chronic stroke survivors - those whose stroke occurred more than six months earlier. Lead researcher Doctor Arlene Schmid, a rehabilitation research scientist at Indiana University in the United States, said: 'For people with chronic stroke, something like yoga in a group environment is cost effective and appears to improve motor function and balance.' The study's 47 participants, about three-quarters of them male veterans, were divided into three groups: twice-weekly group yoga for eight weeks; a 'yoga-plus' group, which met twice weekly and had a relaxation recording to use at least three times a week; and a usual medical care group that did no rehabilitation. The yoga classes, taught by a registered yoga therapist, included modified yoga postures, relaxation, and meditation. Classes grew more challenging each week. Compared with patients in the usual-care group, those who completed yoga or yoga-plus significantly improved their balance. The researchers said balance problems frequently last long after a person suffers a stroke, and are related to greater disability and a higher risk of falls. Survivors in the yoga groups also had improved scores for independence and quality of life and were less afraid of falling. Dr Schmid said: 'For chronic stroke patients, even if they remain disabled, natural recovery and acute rehabilitation therapy typically ends after six months, or maybe a year.'
Friday, July 27, 2012
For athletes participating in the London 2012 Olympics, here is a helpful tip! According to a new research, you can now replace your dose of sports chews with the good old raisin as it provides the same workout boost. Researchers from the University of California-Davis found that eating raisins can boost performance in athletes and long distance runners.
A new research has claimed that cheese can prevent diabetes, even as the current health guidelines advise cutting back on dairy products. British and Dutch researchers found that eating just two slices of cheese a day cuts the risk of type 2 diabetes by 12 per cent, the Daily Mail reported. Diabetes can cause heart attacks, strokes, blindness and nerve problems, without yet having been diagnosed. The researchers looked at the diets of 16,800 healthy adults and 12,400 patients with type 2 diabetes from eight European countries, including the UK.
Secretary of State Hillary Clinton announced that the U.S. would be contributing an additional $157 million to the fight against HIV-AIDS, even as a constellation of celebrity speakers at the ongoing International AIDS Conference here admitted that the world continued to face serious challenges in halting the spread of the epidemic. Reflecting on the mixed record of the scientific community seeking a cure for HIV-AIDS Ms. Clinton said, “The ability to prevent and treat the disease has advanced beyond what many might have reasonably hoped 22 years ago. Yes, AIDS is still incurable, but it no longer has to be a death sentence.” With a rare hat-tip to former U.S. President George W. Bush, for setting up the nodal PEPFAR agency in 2003 for fighting HIV-AIDS in the U.S., the Secretary added that under President Barack Obama the U.S.’ focus has been on “shifting out of emergency mode and starting to build sustainable health systems that will help us finally win this fight.” To that end, she announced, the U.S. would be contributing an additional $40 million to support South Africa’s voluntary medical circumcision plans; investing an additional $80 million to ensure that HIV-positive pregnant women receive adequate treatment; $37 million in implementation research, country-specific programmes and civil-society support targeting vulnerable and high-risk populations across the world. India found specific mention as a nation with one of the largest HIV-positive populations globally, when Ms. Clinton said that along with South Africa, Namibia, and Botswana, India, may be able to provide more and better care for its by committing more of its own resources to the cause.
Scientists claimed to have discovered the gene that encourages the spread of breast cancer, paving way for treatments for the disease.
Always avoid alcohol while taking certain medicines because it actually triples the original dose, warn researchers. Lab experiments have demonstrated how alcohol made several drugs up to three times more available to the body, effectively tripling the original dose, said Christel Bergstrom, associate professor of pharmacology at Monash University, who led the study. Bergstrom and colleagues explain that beverage alcohol, or ethanol, can cause an increase in the amount of non-prescription and prescription drugs that are "available" to the body after taking a specific dose, the journal Molecular Pharmaceutics reports.
If you have ever looked over the edge of a cliff and felt dizzy, you understand the challenges faced by people who suffer from symptoms of vestibular dysfunction such as vertigo and dizziness. There are over 70 million of them in North America. For people with vestibular loss, performing basic daily living activities that we take for granted (e.g. dressing, eating, getting in and out of bed, getting around inside as well as outside the home) becomes difficult since even small head movements are accompanied by dizziness and the risk of falling. We've known for a while that a sensory system in the inner ear (the vestibular system) is responsible for helping us keep our balance by giving us a stable visual field as we move around. And while researchers have already developed a basic understanding of how the brain constructs our perceptions of ourselves in motion, until now no one has understood the crucial step by which the neurons in the brain select the information needed to keep us in balance. The way that the brain takes in and decodes information sent by neurons in the inner ear is complex. The peripheral vestibular sensory neurons in the inner ear take in the time varying acceleration and velocity stimuli caused by our movement in the outside world (such as those experienced while riding in a car that moves from a stationary position to 50 km per hour). These neurons transmit detailed information about these stimuli to the brain (i.e. information that allows one to reconstruct how these stimuli vary over time) in the form of nerve impulses. Scientists had previously believed that the brain decoded this information linearly and therefore actually attempted to reconstruct the time course of velocity and acceleration stimuli. But by combining electrophysiological and computational approaches, Kathleen Cullen and Maurice Chacron, two professors in McGill University's Department of Physiology, have been able to show for the first time that the neurons in the vestibular nuclei in the brain instead decode incoming information nonlinearly as they respond preferentially to unexpected, sudden changes in stimuli.
Researchers from the University of Kentucky have designed and discovered a series of highly efficient enzymes that effectively metabolize cocaine. These high-activity cocaine-metabolizing enzymes could potentially prevent cocaine from producing physiological effects, and could aid in the treatment of drug dependency. The results of this study by Chang-Guo Zhan et al are published in the journal PLOS Computational Biology.
A compelling new genetic study tracing the origins of immature egg cells, or 'oocytes', from the embryonic period throughout adulthood adds new information to a growing controversy. The notion of a "biological clock" in women arises from the fact that oocytes progressively decline in number as females get older, along with a decades-old dogmatic view that oocytes cannot be renewed in mammals after birth After careful assessment of data from a recent study published in PLoS Genetics, scientists from Massachusetts General Hospital and the University of Edinburgh argue that the findings support formation of new eggs during adult life; a topic that has been historically controversial and has sparked considerable debate in recent years.
Tuesday, July 24, 2012
Bottlenose dolphins in the northern Gulf of Mexico were hit by a triple whammy of events, leading to an unusually high death rate in early 2011, a paper published in PLoS ONE suggests. Between January and April 2011, 186 bottlenose dolphins (Tursiops truncatus) washed ashore in the northern Gulf of Mexico. Of these, 86 were near-term or newborn, nearly double the historical average. Dolphin deaths are being monitored by an ongoing Unusual Mortality Event (UME) survey, which began in response to high numbers of adult dolphins dying during a period of sustained cold weather in early 2010. The PLoS ONE study suggests that the cold weather was the first of three factors that weakened the dolphin population and contributed to the high death rate. The second was the Deepwater Horizon oil spill that followed in April. And the third was large volumes of cold fresh water from melting snow entering Mobile Bay — an inlet in the Gulf of Mexico — in 2011.
Bioengineers have made an artificial jellyfish using silicone and muscle cells from a rat’s heart. The synthetic creature, dubbed a medusoid, looks like a flower with eight petals. When placed in an electric field, it pulses and swims exactly like its living counterpart. “Morphologically, we’ve built a jellyfish. Functionally, we’ve built a jellyfish. Genetically, this thing is a rat,” says Kit Parker, a biophysicist at Harvard University in Cambridge, Massachusetts, who led the work. The project is described today in Nature Biotechnology.
Polar bears may have trod the planet for millions of years, according to a new genetic analysis. That suggests the white-coated, massive bears have weathered previous natural climate changes, and may predate the Arctic ice that is their preferred—and only—habitat today, which is why the species future remains uncertain presently. "There's no guarantee that they'll survive this time," says geneticist Webb Miller of Pennsylvania State University, an author of the study published July 23 in Proceedings of the National Academy of Sciences. After all, Miller notes, the species currently lacks much genetic diversity to help it adapt to changing conditions as well as facing unprecedented threats such as heavy metal pollution accumulating in the Arctic. By better understanding how old the species is, the scientists hope to better understand what might be done to allow the polar bear to cope with onrushing climate change and other existential challenges. By analyzing the genomes of 28 bears—polar bears, including a roughly 120,000-year-old specimen from Norway's Svalbard archipelago, as well as modern brown bears and black bears—the scientists in effect read back in time to a common ancestor at least four million years ago. That finding conflicts with a genetic analysis published in Science earlier this year that suggested the species was only 600,000 years old or so, which the team behind the new research suggests may result from misreading past interbreeding events with closely related brown bears. In fact, the key problem here may be that technically the polar bear may not be a species at all. "If one defines that two species separate as when they cannot produce viable offspring, then perhaps brown bears and polar bears aren't yet separate species," Miller admits.
Sunday, July 22, 2012
A combination of gold and green tea compounds may be potential treatment for prostate cancer, according to researchers from the University of Missouri. In a new mouse study published in the Proceedings of the National Academy of Sciences, the researchers found that a combination of a compound found in green tea leaves and radioactive gold nanoparticles were able to destroy the tumour cells. The tea compound, which was attracted to the cancerous cells, helped to deliver the gold nanoparticles, which killed the cancer cells. Researchers said large doses of chemotherapy, which sometimes have toxic side effects, are currently used to treat a variety of cancers, but the new treatment would require doses that are "thousands of times" lower than that of chemotherapy. The particles are small enough to destroy the diseased cells, but leave the healthy surrounding tissue and cells intact. "By combining a natural component in green tea that has an affinity for prostate tumour cells, we have formed gold nanoparticles that have a high uptake in tumour cells," ABC News quoted Dr. Cathy Cutler, research professor at the MU Research Reactor and co-author of the study, as saying. "This formulation of gold nanoparticles, which has shown such tumour cell death at such a low dose in a model of aggressive human prostate cancer indicates it could be effective for aggressive prostate cancer," Dr. Cutler noted.
Pearls rich in essential minerals can help treat killer diseases like cancer, a leading scientist has claimed. In a series of experiments by Ajai Kumar Sonkar at the Pearl Aquaculture Research Foundation in Port Blair, pearls produced through special culture technique have been found to contain traces of several metals and minerals which are known to have major health benefits. “We have produced the pearls in a controlled environment in the lab in most aseptic conditions. They are found to contain traces of metal and minerals such as zinc, copper, magnesium, iron, calcium, sodium and potassium,” Sonkar said. “These micro-nutrients are essential for various body functions such as metabolism, growth and immunity. Of them, zinc has been found to be playing a major role in preventing fatal diseases like cancer,” he told PTI. A study, published recently in the British Journal of Cancer, has also established zinc’s anti-tumour role that prevents the growth of cancer cells. Other studies have also found that zinc deficiency in the body causes delayed healing of wounds. It is also found to play a leading role in weight loss, help decrease the severity and duration of cold and several other illnesses. According to Sonkar, they have produced pearls from four different species of pearl oysters. “The bio availability of zinc in the pearls can be exploited to help treat several diseases.” For scientific analysis, the scientist had sent samples of pearl powder to the Indian Council of Agricultural Research’s Central Institute of Fisheries Technology in Cochin, which established the pearls do contain all the mentioned metals and minerals.
“Bacteria” has been a bad word, spelling infections and diseases. But the latest Human Microbiome project has something different to say. What it says can change the way we look at ourselves and our ailments...and of course influence our attitude towards bacteria.
That chimpanzees have a close evolutionary relation with human beings is a known fact. But recent research suggests that even our language might have been evolved from the variety of gestures used by chimpanzees to communicate with each other. A Stirling researcher has identified between 20 and 30 manual gestures used by a community of wild chimpanzees to communicate with others in a range of activities including nursing, feeding, sex, aggression and defence. Interestingly, a third of these gestures could have been used by humans during their evolving stage to develop language. Postgraduate researcher at the University of Stirling, Dr. Anna Roberts, found that chimpanzees use arm beckoning gestures to make another approach them, flail their arms to make another leave, use begging gestures to make others pass food and clap their hands to express excitement. The study is the first to show that wild chimpanzees are so close to humans in terms of their communicative abilities and these gestures suggest that the common ancestor of humans and chimpanzees must have used similar manual gestures. Dr. Roberts said: “Chimpanzees use these gestures intentionally to elicit a desired response from other chimpanzees and they may be the missing link between ape and human communication.” She added: “We now know that these gestures must have been in the repertoire of our common ancestor and might have been the starting point for language evolution. Manual gesture in chimpanzees is controlled by the same brain structures as speech in the human brain.” Dr. Roberts claimed that chimpanzees not only communicate using manual gestures, but they are able to work out what the signaller means from both gesture and accompanying context.
Researchers have created a collection of “bryologs” — derived from a tiny marine organism, that been shown to activate latent HIV reservoirs with equal or greater potency than the original substance. A collection of “bryologs” activate hidden reservoirs of the virus that currently make the disease nearly impossible to eradicate. Thanks to antiretrovirals, an AIDS diagnosis hasn’t been a death sentence for nearly two decades. But highly active antiretroviral therapy, or HAART, is also not a cure. Patients must adhere to a demandingly regular drug regimen that carries plenty of side effects. And while the therapy may be difficult to undergo in the United States, it is nearly impossible to scale to the AIDS crisis in the developing world. The problem with HAART is that it doesn’t address HIV’s so-called proviral reservoirs — dormant forms of the virus that lurk within T-cells and other cell types. Even after all of the body’s active HIV has been eliminated, a missed dose of antiretroviral drugs can allow the hibernating virus to emerge and ravage its host all over again. "It’s really a two-target problem,” Professor Paul Wender from Stanford said. "And no one has successfully targeted the latent virus,” he said. But Wender’s lab is getting closer, exciting many HIV patients hoping for a cure. The lab’s work may give doctors a practical way to flush out the dormant virus. The first attempts to reactivate latent HIV were inspired by observations of Samoan healers. When ethnobotanists examined the bark of Samoa’s mamala tree, traditionally used by healers to treat hepatitis, they found a compound known as prostratin. Prostratin binds to and activates protein kinase C, an enzyme that forms part of the signalling pathway that reactivates latent viruses. The discovery sparked interest in the enzyme as a potential therapeutic target, especially as it was discovered that prostratin isn’t the only biomolecule to bind to the kinase. The bryozoan Bugula neritina — a mossy, colonial marine organism — produces a protein kinase C—activating compound that is many times more potent than prostratin. The molecule, named bryostatin 1, was deemed to hold promise as a treatment, not only for HIV but for cancer and Alzheimer’s disease as well. The National Cancer Institute initiated a Phase II clinical trial for the compound in 2009 for the treatment of non-Hodgkin lymphoma. But the substance had a number of side effects and proved prohibitively difficult to produce. "It took 14 tons of bryozoans to make 18 grams of bryostatin,” Wender said. "They’ve stopped accrual in trials because, even if the trials worked, the compound cannot be currently supplied,” he said. Patient enrolment was suspended until more accessible compounds came out of the Wender Group’s lab. Wender, who published the first practical synthesis of prostratin and its analogs in 2008, had set out to make a simpler, more effective synthetic analog of bryostatin. "We can copy the molecule or we can learn how it works and use that knowledge to create something that has never existed in nature and might be superior to it,” he said.
The amount of structural damage that radiation causes in electronic materials at the atomic level may be at least ten times greater than previously thought. That is the surprising result of a new characterization method that uses a combination of lasers and acoustic waves to provide scientists with a capability tantamount to X-ray vision: It allows them to peer through solid materials to pinpoint the size and location of detects buried deep inside with unprecedented precision. The research, which was conducted by post-doctoral fellow Andrew Steigerwald under the supervision of Physics Professor Norman Tolk, was published online on July 19 in the Journal of Applied Physics. "The ability to accurately measure the defects in electronic materials becomes increasingly important as the size of microelectronic devices continues to shrink," Tolk explained. "When an individual transistor contains millions of atoms, it can absorb quite a bit of damage before it fails. But when a transistor contains a few thousand atoms, a single defect can cause it to stop working." Previous methods used to study damage in electronic materials have been limited to looking at defects and deformations in the atomic lattice. The new method is the first that is capable of detecting disruption in the positions of the electrons that are attached to the atoms. This is particularly important because it is the behavior of the electrons that determine a material's electrical and optical properties. "An analogy is a thousand people floating in a swimming pool. The people represent the atoms and the water represents the electrons," said Steigerwald. "If another person – representing an energetic particle – jumps into the pool, the people in his vicinity change their positions slightly to make room for him. However, these shifts can be fairly subtle and difficult to measure. But the jumper will also cause quite a splash and cause the level of the water in the pool to rise. Much like the water in the pool, the electrons in a material are more sensitive to defects than the atoms." To detect the electron dislocations, the physicists upgraded a 15-year-old method called coherent acoustic phonon spectroscopy (CAPS). "CAPS is similar to the seismic techniques that energy companies use to search for underground oil deposits, only on a much smaller scale," said Steigerwald. Oil explorers set off a series of small explosions on the surface and measure the sound waves that are reflected back to the surface. That allows them to identify and map the layers of different types of rock thousands of feet underground. Similarly, CAPS generates a pressure wave that passes through a chunk of semiconductor by blasting its surface with an ultrafast pulse of laser light. As this happens, the researchers bounce a second laser off the pressure wave and measure the strength of the reflection. As the pressure wave encounters defects and deformities in the material, its reflectivity changes and this alters the strength of the reflected laser light. By measuring these variations, the physicists can detect individual defects and measure the effect that they have on the material's electrical and optical properties.
Researchers from the University of California, San Francisco (UCSF) and Makerere University in Uganda have used hair and blood samples from three-month old infants born to HIV-positive mothers to measure the uninfected babies' exposure—both in the womb and from breast-feeding—to antiretroviral medications their mothers were taking. The results, they said, are surprising. "We found high levels of exposure to three antiretroviral medications in the hair samples of HIV uninfected infants at twelve weeks of life," said study senior author, Monica Gandhi, MD, MPH, associate professor of medicine at the UCSF Division of HIV/AIDS at San Francisco General Hospital and Trauma Center (SFGH). "From looking at plasma level data at the same time point, we believe that transfer of two of the medicines from mother to baby occurs exclusively in the womb and transfer of the third medication occurs both in the womb and through breastfeeding." The findings could lead to new ways to protect infants from HIV transmission and to better understand the development of toxicities and resistance to the drugs, the researchers said. A single plasma level of a medication reflects drug exposure over approximately 24 hours. Measuring the concentrations of antiretrovirals in a small hair sample reveals exposure over the past month. The team therefore measured both plasma and hair levels of medications in babies whose mothers were taking HIV medications to get a better idea of when drugs are being passed from mother to baby. "Since fetuses start growing hair in the womb, hair sampling gives us an opportunity to examine exposures to drug before birth," said Gandhi. UCSF researchers have pioneered the use of hair sampling for measuring antiretroviral levels. The procedure is now a standard measure in many research studies, equivalent in HIV clinical care to measuring hemoglobin A1C to monitor average blood glucose levels in patients with diabetes. In the study, the team took hair and blood samples from two groups of HIV-positive mothers, all of whom breast-fed their infants. For 45 mother/infant pairs, the mothers' antiretroviral regimens included a protease inhibitor, lopinavir, boosted by ritonavir, another antiretroviral medication. The other 64 mothers were on an efavirenz-based regimen. Infants in the lopinavir group had levels of the drug in their hair that measured 87 percent of the levels found in their mothers' hair. The levels of ritonavir were about 45 percent of the levels found in their mothers' hair. When the researchers looked at the drug levels in the blood drawn from the mothers and infants at 12 weeks, they found the expected levels of lopinavir and ritonavir in the mothers, but none of either in the blood of the infants. The inability to find drug in the infants' blood at 12 weeks tells us that the lopinavir and ritonavir in their hair is not due to recent exposure, so breast-feeding did not transfer these drugs to the infants. Our conclusion is that the lopinavir and ritonavir were transferred to the babies in the womb, and lopinavir at quite a high level," said Gandhi. In the efavirenz group, researchers found infant drug levels in hair samples that were about 40 percent of the levels found in their mothers. Additionally, they found that infants had levels in their blood that were about 15 percent of what was found in their mothers. These findings indicate a moderate transfer of efavirenz both in the womb and during breastfeeding said Gandhi. "Our findings, as we verify them, will have important implications. One, being able to measure drug exposures of fetuses in the womb and during breast-feeding can help us understand how to better protect infants from HIV transmission from HIV-positive mothers during pregnancy, birth and after birth. Antiretroviral medications are delivered prophylactically to HIV-positive mothers and newborns to prevent transmission, and fetuses derive protection from transmission if their HIV-positive mothers are on an antiretroviral regimen," she said. "Second, the development of resistance to antiretroviral medications in infants is an important issue. HIV develops resistant mutations after fairly low levels of exposure to the class of medications to which efavirenz belongs, non-nucleoside transcriptase inhibitors (NNRTIs). Additionally, hair sampling for antiretroviral exposure levels will ultimately help us monitor toxicities associated with these medications in infants." Using hair to measure exposure to antiretrovirals has advantages in that it is a painless, bloodless, biohazard-free method of collecting a stable specimen from HIV patients. It measures drug exposure over time and has been shown to be more predictive of treatment response than the "snapshot" of exposure provided by a single plasma level of medication. Gandhi said that researchers are finding hair sampling to be a very useful tool in several settings. One use is in resource-limited settings where collecting, storing and handling blood draws is difficult and expensive. Hair is snipped, wrapped in foil and needs no refrigeration.
Friday, July 20, 2012
Scientists have developed a new, free iPhone application which could help you conduct a self exam to detect potential skin cancer, but there is a catch: You will have to fully expose yourself for results. Developed by a team at the University of Michigan in the US, the new app, called UM SkinCheck, aims to make the already existing whole body photographic self-diagnosis a bit simpler and cheaper.
A Russian entrepreneur, who heads a hi-tech research project called 'Avatar' , has contacted the world's richest to offer them immortality. Itskov claims that he will personally oversee their immortality process in exchange for an undisclosed fee.
Astronomers at the University of California, Santa Cruz, and the Carnegie Institution of Washington believe they have discovered a planet right at Earth's front door that may be capable of supporting human life. The planet is 22 light years away, previously thought to be 20 light years, and is formally known as Gliese 581g, but lead researcher Professor Steven Vogt told News.com.au that he has since named it after his wife. "I called it 'Zarmina's world'. It's not just in our backyard, it's right in our face," Professor Vogt said. The study, which was released to News.com.au this week, showed that the planet was twice the size of earth. It is known as a "super Earth" due to its ability to hold on to its gassy atmosphere, which increases its chances of retaining liquid. Whether this liquid is frozen and stored under the surface or flowing freely across the planet, the researchers can't say. The scientist from the University of California said that the planet has "churchly weather" similar to what we experience in Australia. "From the energy bounds and brightness of the star we can tell that the temperatures would be just about right to stand on the surface and feel the warmth of the alien star on your face, like standing in the park in Sydney," he explained. However the researchers were unable to determine what the surface of the planet is like, Professor Vogt said.
A crucial, and often underappreciated, facet of science lies in deciding how to turn the raw numbers of data into useful, understandable information – often through graphs and images. Such visualization techniques are needed for everything from making a map of planetary orbits based on nightly measurements of where they are in the sky to colorizing normally invisible light such as X-rays to produce "images" of the sun. More information, of course, requires more complex visualizations and occasionally such images are not just informative, but beautiful too.