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Archive - May 2011 - Story

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May 29th

How Influenza Triggers Attacks in Asthmatics

When children with asthma get the flu, they often land in the hospital gasping for air. Researchers at Children's Hospital Boston and collaborating institutions have found a previously unknown biological pathway explaining why influenza induces asthma attacks. Studies in a mouse model, published online on May 29, 2011 by the journal Nature Immunology, reveal that influenza activates a newly recognized group of immune cells called natural helper cells – presenting a completely new set of drug targets for asthma. If activation of these cells, or their asthma-inducing secretions, could be blocked, asthmatic children could be more effectively protected when they get the flu and possibly other viral infections, says senior investigator Dr. Dale Umetsu, of Children's Division of Immunology. Although most asthma is allergic in nature, attacks triggered by viral infection tend to be what put children in the hospital, reflecting the fact that this type of asthma isn't well controlled by existing drugs. "Virtually 100 percent of asthmatics get worse with a viral infection," says Dr. Umetsu. "We really didn't know how that happened, but now we have an explanation, at least for influenza." Natural helper cells were first, very recently, discovered in the intestines and are recognized to play a role in fighting parasitic worm infections as part of the innate immune system (our first line of immune defense). "Since the lung is related to the gut – both are exposed to the environment – we asked if natural helper cells might also be in the lung and be important in asthma," Dr. Umetsu says. Subsequent experiments, led by first authors Drs. Ya-Jen Chang and Hye Young Kim in Dr. Umetsu's lab, showed that the cells are indeed in the lung in a mouse model of influenza-induced asthma, but not in allergic asthma.

Pre-Implantation Genetic Diagnosis Can Prevent Passing on of Mitochondrial Diseases

Pre-implantation genetic diagnosis (PGD) can give women at risk of passing on a mitochondrial DNA disorder to their offspring a good chance of being able to give birth to an unaffected child, a researcher told the annual conference of the European Society of Human Genetics on May 30, 2011. Dr. Debby Hellebrekers, from Maastricht University Medical Centre, Maastricht, The Netherlands, said that the scientists' findings could have a considerable effect on preventing the transmission of mitochondrial diseases. Mitochondria are cellular organelles involved in the conversion of the energy of food molecules into ATP, the molecule that powers most cellular functions. Disruptions of this energy-producing process, due to a defect in the mitochondrial DNA (mtDNA) or nuclear genes, can cause mitochondrial disorders which represent the most common group of inborn errors of metabolism. The manifestation of mtDNA disorders can be quite varied, but the diseases are almost always serious and, if they do not lead to death, they can result in life-long serious disability for children born with them. Symptoms of mtDNA disorders include loss of muscle co-ordination, visual and hearing problems, poor growth, mental retardation, heart, liver, and kidney disease, neurological problems, respiratory disorders, and dementia. Prenatal diagnosis is in general not possible for mtDNA diseases, because the clinical signs cannot be reliably predicted from the mutation load (the relative amount of mutated mtDNA molecules) in chorionic villus sampling, so the team of scientists from The Netherlands, Australia, and the UK decided to look at whether PGD would be a better alternative. "If we could find a minimal level of mtDNA mutation load below which the chance for an embryo of being affected was acceptably low," said Dr.

May 29th

E-Cadherin Is a Key Molecule for Stem Cell Pluripotency

Researchers at the Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch and collaborating institutions have discovered what enables embryonic stem cells to differentiate into diverse cell types and thus to be pluripotent. This pluripotency depends on a specific molecule – E-cadherin – hitherto primarily known for its role in mediating cell-cell adhesion as a kind of “intracellular glue”. If E-cadherin is absent, the stem cells lose their pluripotency. The molecule also plays a crucial role in the reprogramming of somatic cells (body cells) into pluripotent stem cells. The work was reported online in EMBO Reports on May 27, 2011. Dr. Daniel Besser, Prof. Walter Birchmeier, and Torben Redmer from the MDC, a member of the Helmholtz Association, used mouse embryonic fibroblasts (MEFs) in their stem cell experiments. In a first step they showed that the pluripotency of these stem cells is directly associated with the cell-adhesion molecule E-cadherin. If E-cadherin is absent, the stem cells lose their pluripotency. In a second step, the researchers investigated what happens when somatic cells that normally neither have E-cadherin nor are pluripotent are reprogrammed into a pluripotent stem cell state. In this reprogramming technique, somatic cells are converted into induced pluripotent stem cells (iPSCs). This new technique may help researchers avoid the controversies that come with the use of human embryos to produce human embryonic stem cells for research purposes. The MDC researchers found that in contrast to the original cells, the new pluripotent cells derived from mouse connective tissue contained E-cadherin. “Thus, we have double proof that E-cadherin is directly associated with stem-cell pluripotency.

Low Vitamin D Levels a Risk Factor for MS in African Americans

In the first major study exploring the connection between vitamin D and multiple sclerosis in African Americans, a team of scientists at the University of California, San Francisco has discovered that vitamin D levels in the blood are lower in African Americans who have the disease, compared to African Americans who do not. “It seems relatively clear,” said Dr. Ari Green, who is the assistant director of the UCSF Multiple Sclerosis Center, director of the UCSF Neurodiagnostics Center and the senior author on the study. “Low vitamin D levels are a risk factor for developing multiple sclerosis.” Published online on May 24, 2011, in the journal Neurology, the results of the study are consistent with observations in Caucasian populations that link low vitamin D levels to having multiple sclerosis. However, the research could not explain why multiple sclerosis tends to be more severe in African Americans even though the disease is less common than in Caucasian populations. Earlier work by the same UCSF team established that African Americans tend to become disabled faster with multiple sclerosis, more frequently having to rely on canes and wheel chairs. “If we can understand why, we may be able to improve treatment for those patients,” said neurologist Dr. Bruce Cree, another author of the paper and one of the primary investigators. Vitamin D levels alone could not account for this apparent difference in severity, the study found. “There are likely other factors that drive the severity of the disease including genes and other environmental factors such as smoking,” said Dr, Jeffrey Gelfand, the first author on the study. Work is now underway to determine how genetic differences may affect the severity of multiple sclerosis.

May 26th

Ziram Pesticide Implicated As a Possible Cause of Parkinson’s Disease

In April 2009, researchers at UCLA announced they had discovered a link between Parkinson's disease and two chemicals commonly sprayed on crops to fight pests. That epidemiological study didn't examine farmers who constantly work with pesticides but people who simply lived near where farm fields were sprayed with the fungicide maneb and the herbicide paraquat. It found that the risk for Parkinson's disease for these people increased by 75 percent. Now a follow-up study adds two new twists. Once again the researchers returned to California's fertile Central Valley, and for the first time have implicated a third pesticide, ziram, in the pathology of Parkinson's disease. Second, instead of looking just at whether people lived near fields that were sprayed, they looked at where people worked, including teachers, firefighters and clerks who worked near, but not in, the fields. They found that the combined exposure to ziram, maneb and paraquat near any workplace increased the risk of Parkinson's disease (PD) threefold, while combined exposure to ziram and paraquat alone was associated with an 80 percent increase in risk. The results were published online on April 20, 2011, in the European Journal of Epidemiology. "Our estimates of risk for ambient exposure in the workplaces were actually greater than for exposure at residences," said Dr. Beate Ritz, senior author and a professor of epidemiology at the UCLA School of Public Health. "And, of course, people who both live and work near these fields experience the greatest PD risk. These workplace results give us independent confirmation of our earlier work that focused only on residences, and of the damage these chemicals are doing." In addition, Dr.

May 25th

Reindeer Can See UV Light

Researchers have discovered that the ultraviolet (UV) light that causes the temporary but painful condition of snow blindness in humans is life-saving for reindeer in the arctic. A Biotechnology and Biological Sciences Research Council (BBSRC)-funded team at University College London and other institutions published a paper in the June 15, 2011 issue of the Journal of Experimental Biology that shows that this remarkable visual ability is part of the reindeer's unique adaptation to the extreme arctic environment where they live. It allows them to take in live-saving information in conditions where normal mammalian vision would make them vulnerable to starvation, predators, and territorial conflict. It also raises the question of how reindeer protect their eyes from being damaged by UV, which is thought to be harmful to human vision. The paper served as the cover story for the Journal of Experimental Biology issue. Lead researcher Professor Glen Jeffery said "We discovered that reindeer can not only see ultraviolet light, but they can also make sense of the image to find food and stay safe. Humans and almost all other mammals could never do this as our lenses just don't let UV through into the eye. "In conditions where there is a lot of UV – when surrounded by snow, for example – it can be damaging to our eyes. In the process of blocking UV light from reaching the retina, our cornea and lens absorb its damaging energy and can be temporarily burned. The front of the eye becomes cloudy and so we call this snow blindness.

Researchers Study Red Wine Component in Treatment of Concussions

University of Texas Southwestern Medical Center researchers are engaging the help of professional boxers and trainers to study whether a component in red wine and grapes could help reduce the short- and long-term effects of concussions. Researchers plan to recruit about two dozen professional boxers to take the neuroprotective compound resveratrol after a fight to see if it reduces damage to the brain after impact and helps restore subtle brain functions and connections via its antioxidant effects. If successful, researchers hope the results may be applicable not only to concussions in other sports such as football and hockey, but also to everyday incidents such as falls, auto accidents, and other blows to the head. "We know from animal studies that if we give the drug immediately after or soon after a brain injury, it can dramatically and significantly reduce the damage you see long term," said Dr. Joshua Gatson, assistant professor of surgery in Burn/Trauma/Critical Care and principal investigator for the study. "There haven't been any completed human studies yet, so this is really the first look at resveratrol's effect on traumatic brain injury." Resveratrol is already being studied as an agent to lower blood sugar levels, for use against cancer, to protect cardiovascular health, and in stroke and Alzheimer's disease treatments. "Even though resveratrol is found in red wine, you would need 50 glasses of wine to get the required dose to get the protection you would need," said Dr. Gatson. He came up with the idea for the trial, called the REPAIR study, while watching ESPN. Being a sports fan, he saw frequent concussion issues in football.

May 25th

Pancake Batfish Among Top 10 New Species Described in 2010

The International Institute for Species Exploration at Arizona State University and a committee of taxonomists from around the world announced their picks for the top 10 new species described in 2010. Among their top picks is Halieutichthys intermedius, a pancake batfish recently discovered by Dr. Prosanta Chakrabarty, curator of fishes at Louisiana State University’s'mMuseum of Natural Science, and colleagues. Halieutichthys intermedius, more commonly referred to as the Louisiana pancake batfish, gained some notoriety during the spring and summer of 2010, when the Deepwater Horizon oil spill affected their primary habitat in the Gulf of Mexico. According to the Top 10 writeup, the batfish was considered one of the top discoveries first because of its precarious existence due to the fact that its entire habitat was covered in oil from the spill, and second, because it is quite a unique-looking fish. "This species is one of only 70 or so of the 1,500 Gulf of Mexico species that is endemic (i.e., only found in the region). All the other species are found in the open Atlantic, Caribbean or other areas," said Dr. Chakrabarty. "Because of their limited distribution, endemics like this new species are of special concern. In a way, this new batfish has become the poster child for the aquatic life threatened by the oil spill. It reminded me both of how little we knew about the biota in the Gulf and also about how the spill can impact some species more than others." Dr. Chakrabarty, who also serves as assistant professor of biological sciences, discovered the new species after studying samples of batfish stored in alcohol-filled jars. It wasn't long before he and Taiwanese colleague Dr. Hsuan-ching "Hans" Ho, and American Museum of Natural History Curator Dr. John Sparks, noticed consistent differences among the specimens.

May 23rd

Microchip Allows Health Assessments from Single Cells

There's a wealth of health information hiding in the human immune system. Accessing it, however, can be very challenging, as the many and complex roles that the immune system plays can mask the critical information that is relevant to addressing specific health issues. Now, research led by scientists from the California Institute of Technology (Caltech) has shown that a new generation of microchips developed by the team can quickly and inexpensively assess immune function by examining biomarkers—proteins that can reflect the response of the immune system to disease—from single cells. The scientists reported on their advanced technology in the May 22 online issue of Nature Medicine. "The technology permits us for the first time to quantitatively measure the levels of many functional proteins from single, rare immune cells," says Dr. James Heath, the Elizabeth W. Gilloon Professor and professor of chemistry at Caltech and corresponding author of the study. "The functional proteins are the ones that are secreted by the cells, and they control biological processes such as cell replication and inflammation and, specific to our study, tumor killing." In 2008, Dr. Heath—an expert in molecular electronics and personalized medicine—led the development of a "barcode chip" that, using just a pinprick's worth of blood, could measure the concentrations of dozens of proteins, including those that herald the presence of diseases like cancer and heart disease. This latest single-cell barcode chip (SCBC) device builds upon the success of that initial design, which is currently being utilized in diagnostic medical testing of certain cancer patients. The researchers tested the chip by measuring a cancer patient's response to a type of cell-based immunotherapy designed to target and kill tumor cells.

May 20th

Personalized Medicine 4.0 Conference: Focus on Pharmacogenomics & Consumer Genetic Testing

This year’s Personalized Medicine Conference (4.0) will be held Thursday, May 26 from 8 am to 7 pm at the South San Francisco Conference Center on the campus of San Francisco State University. This fourth annual conference on personalized medicine focuses on two exciting areas – pharmacogenomics (the right drug, at the right dose, for the right patient, at the right time) and the controversial topic of direct-to-consumer genetic testing, examining the science, the business, and the social dimensions of each. Personalized Medicine 4.0 is a one-day conference and networking opportunity for health and industry professionals, educators, and scientists. Learn how the new genomic medicine will affect your work and your life. Seating is limited. Register now at http://personalizedmedicine.sfsu.edu. For additional information or to sponsor this event, please e-mail dnamed@sfsu.edu or call Arlene Essex at 415-405-4107. Contact us for academic rates.