Asthma linked to DNA damage.

An image of epithelial cells surrounding a lung bronchiole in mice with asthma induced by dust mites. Researchers have shown that this type of asthma also produces DNA damage in lung cells, which is indicated in green.(Image: Tze Khee Chan) House dust mites, which are a major source of allergens in house dust, can cause asthma in adults and children. Researchers from MIT and the National University of Singapore have now found that these mites have a greater impact than previously known — they induce DNA damage that can be fatal to lung cells if the damaged DNA is not adequately repaired. The findings suggest that DNA repair capacity, which varies widely among healthy individuals, could be a susceptibility factor that places an asthmatic patient at increased risk of developing asthma-associated pathologies, the researchers say. “DNA damage is a component in asthma development, potentially contributing to the worsening of asthma. In addition to activation of immune responses, patients’ DNA repair capacity may affect disease progression,” says Bevin Engelward, a professor of biological engineering at MIT and a senior author of the study. “Ultimately, screening for DNA repair capacity might be used to predict the development of severe asthma.” Fred Wong Wai-Shiu, head of the Department of Pharmacology at the National University of Singapore, is also a senior author of the study, which appears in the May 1 issue of the Journal of Allergy and Clinical Immunology. The paper’s lead author is Tze Khee Chan, a graduate student in the Singapore-MIT Alliance for Research and Technology (SMART) Asthma is usually triggered by an exaggerated immune response to allergens such as dust mites, pollen, or pet dander. Immune cells flood the lung where the allergen has invaded, secreting immune chemicals called cytokines that drive inflammation and constriction of the smooth muscle, leading to narrowing of the airways and making breathing difficult. More than 300 million people suffer from asthma worldwide, and in the United States about 8 percent of the population is affected. The research team focused on dust-mite-induced allergies because dust mites are ubiquitous and thrive in warm, humid climates. Dust mites provoke allergic symptoms, such as sneezing and watery eyes, and in sensitive individuals dust mites can even trigger allergic asthma. Up to 85 percent of patients with asthma are allergic to dust mites, making it the main trigger for allergic asthma. When the researchers exposed mice to dust mites, to induce an asthma-like condition, they found an alternative pathway that contributes to asthma development. In these mice, the dust mites caused production of chemicals called reactive oxygen and nitrogen species (RONS), which are known for their potential to damage DNA and other biological molecules. Furthermore, when DNA repair is inhibited using a drug called NU7441, more DNA damage and cell death are observed. There is a wide range of DNA repair capacity among people, so the findings suggest that asthma patients with poor DNA repair capacity could be more susceptible to asthma-induced inflammation and tissue damage. Although the mechanism is not known, dust mites can also directly induce DNA damage when they come into contact with cultured human cells. “Our findings show that dust mites can not only induce an immune response, they can also cause direct DNA damage in the lung epithelial cells. These damaging effects are magnified when DNA repair is inhibited. It shows how important DNA repair is to prevent cell death,” Chan says. “Our current understanding is that inflammatory cells, such as eosinophils, neutrophils, and macrophages, produce free radicals that damage the cell. But right now what we observe is the epithelial cell by itself, without the other cells, can actually produce free radicals when exposed to dust mites. This is a finding that has not been reported before,” Wong says. The findings provide additional data to support the possibility of treating asthma patients with antioxidants to neutralize the RONS, in order to help prevent asthma-induced tissue damage. The researchers are now testing this approach in mice. “This important report suggests that a paradigm shift may now be in order for allergens as environmental agents, and also for our understanding of the steps by which inhaled allergens interact with the lung to induce allergic asthma,” says Michael Fessler, a senior investigator at the National Institute of Environmental Health Sciences, who was not involved in the research. Finally, the results suggest that DNA damage may also be an important underlying factor in asthma exacerbation caused by inflammation during infectious diseases such as rhinovirus infection, the researchers say.Culled from MIT NEWS

LABRADOR RETRIEVER AND OBESITY GENE..

A new University of Cambridge study shows that Chubby labrador retrievers may be genetically predisposed to obesity. This research has been published in the journal Cell Metabolism,the dog – which is the most popular breed in the UK – is often considered to be "obsessed with food", say the researchers,this could be explained by the gene. 310 pet and assistance Labradors were weighed, assessed, and given a "body condition score". The team also "searched for variants of obesity-related genes" and assessed food-motivation via a diary kept by dog owners. The research found that one particular gene – POMC – was associated with obesity in the Labradors, with around one in four Labradors thought to carry the gene. It affects how the brain regulates and recognizes the feeling of hunger – meaning the dogs may carry on eating when they're full. "This is a common genetic variant in Labradors and has a significant effect on those dogs that carry it, so it is likely that this helps explain why Labradors are more prone to being overweight in comparison to other breeds," said Eleanor Raffman, lead author of the research. "People who live with Labradors often say they are obsessed by food, and that would fit with what we know about this genetic change." The team says the research may also have an impact on our understanding of human obesity. "Common genetic variants affecting the POMC gene are associated with human body weight and there are even some rare obese people who lack a very similar part of the POMC gene to the one that is missing in the dogs. So further research in these obese Labradors may not only help the well being of companion animals but also have important lessons for human health," said Stephen O'Rahilly, who also worked on the research. Obesity in dogs can cause diabetes, heart disease, cancer and a reduced lifespan as also observed in man. culled from wired.co.uk

Robot carries out first autonomous soft tissue surgery.

A robot has for the first time carried out fully autonomous surgery on a live subject: an intestinal anastomosis on a pig, during which two loops of intestine were stitched together. Four surgeries were carried out and all the subjects survived without complications. A paper in Science Translational Medicine shows how , the Smart Tissue Autonomous Robot (STAR) was created by a team of surgeons and scientists at the Sheikh Zayed Institute for Pediatric Surgical Innovation at the USA's Children's National Health System in Washington, DC. As well as live (in vivo) surgery, STAR also carried out surgeries on inanimate (ex vivo) porcine tissue, including both intestinal anastomosis and linear suturing. When compared to the intestinal anastomosis procedures carried out both manually by experienced surgeons and with existing robot-assisted surgical techniques using the daVinci Surgical System, STAR was found to outperform both in terms of surgical quality. The results of the procedures were assessed on factors such as "consistent suture spacing, which helps to promote healing, and in withstanding higher leak pressures, as leakage can be a significant complication from anastomosis surgery". However, STAR currently takes longer than a surgeon working manually: 35 minutes, to a human's eight minutes. Its time is comparable to the time it takes humans to carry out laparoscopic intestinal anastomosis – keyhole surgery that relies on tiny cameras to track progress and haptic feedback instruments to do the suturing. Dr Peter C. Kim said that "the intent of this demonstration is not to replace surgeons, but to expand human capacity and capability through enhanced vision, dexterity and complementary machine intelligence for improved surgical outcomes." STAR is designed to improve the accuracy of always-challenging soft tissue surgery, allowing a human surgeon to invest their expertise by supervising the procedure and interrupting if necessary, while the robot plans and performs the soft tissue sutures. Technical lead Axel Krieger says that "by using novel tissue tracking and applied force measurement, coupled with suture automation software, our robotic system can detect arbitrary tissue motions in real time and automatically adjust." Until STAR's development, says Krieger, "autonomous robot surgery has been limited to applications with rigid anatomy, such as bone cutting, because they are more predictable." STAR tracks the position of flexible soft tissues using near infrared florescent (NIRF) markers applied to the areas it needs to suture, monitored by a camera system that's able to see in three dimensions. An intelligent algorithm guides the robot's surgical plan and allows it to autonomously adjust and react in real time as tissue moves. It also has finely calibrated force sensors and actuators and an articulated laparoscopic suturing tool with eight degrees of movement – one more than the human arm, according to Science, which also provides video footage of the robot performing surgery on inanimate tissue. Dr Kim says that the next step in STAR's development will be to create improved sensors and further miniaturise the tools used by the robot. He says that, if the team can find a suitable partner to develop the technology, we could be seeing it in clinical use in as little as two years. culled from wired.co.uk

Paranoia 'reduced' by virtual reality therapy

In a study published in the British Journal of Psychiatry, an Oxford University team found that patients experiencing paranoia could have their symptoms alleviated through a VR experience.Virtual reality has been used to treat conditions like autism, PTSD and depression,now new study claims that it could be used to reduce persecutor y delusions in patients with paranoia. "The patients had tried standard treatments, like medication, but still had strong paranoia," Daniel Freeman told WIRED. Freeman, who is a professor of clinical psychology at Oxford University, worked on the project. "So the benefits of VR were shown for people who had difficulties despite treatment in mental health services." The experiment used patients with persecutor y delusions – people who mistakenly think that others are watching them or are trying to cause them harm of some kind. This can often lead to safety-seeking behavior, wherein patients believe that particular threats was averted because of avoidance rather than because the threat was erroneous to begin with. For example, a patient may believe that they weren't attacked because they got off a bus when they felt paranoid, rather than because they were unlikely to be attacked in the first place. Almost all patients with persecutor y paranoia indulge in this kind of safety-seeking behavior. To examine how to alleviate or reduce this kind of behavior, the team developed a VR experience to expose patients to situations that were likely to cause them paranoia-related anxiety. Virtual social environments could provide a means for patients with severe paranoid to make the first steps towards entering their feared situations before taking the learning into the real world . 30 patients with persecutor y delusions were first asked to complete a 5 minute behavioral test in which they entered a real life social environment they were scared of (for example entering the Tube or walking to a shop). They were then given virtual reality cognitive therapy, and asked to rate how strong their conviction in their delusion was before and after each VR experience. Compared to patients who underwent exposure therapy, VR cognitive therapy led to "large reductions in delusional conviction". Freeman hopes that the technique could be used further – "undoubtedly, VR could go on to have a central role in mental health clinics and wards" – and thinks that the best time to target patients is during an early onset of an episode. "Arguably, the best treatment approach would be to help people at the earliest stages of their problems," he said. "One could envisage people using VR at home delivered via a smartphone. Generally, the longer and more severe a problem then the greater the therapist time needed to help complement a technological treatment device." "So the earlier the problem is caught, the greater the likelihood the person can overcome it alone using VR." At this point in the research, the team view the project as "another treatment to add to those provided in services". But they also say that VR could be "especially potent" for the treatment of persecutory paranoia because it targets the key issue of a sense of danger. "With VR, we can help patients relearn safety, and in this way the paranoia begins to fade away." Barriers to access are slowly lifting, though – while such services were previously limited because of "the cost and specialist technological support needed" to run programs like this, this is now changing. culled from wired

U.S. kills 39,000 turkeys in outbreak of mild bird flu - OIE

U.S. authorities destroyed 39,000 turkeys in Missouri due to an outbreak of a mild form of avian flu, the World Organization for Animal Health said on Tuesday, as officials remained on alert for new cases. State authorities also have begun a quarantine and taken surveillance measures around the farm in Jasper County that was hit with the H5N1 strain of the virus to watch for other cases, according to the Missouri Department of Agriculture. All commercial flocks within a 10-kilometer radius of the farm have tested negative, the department said. The outbreak, which was detected late last month, is considered low pathogenic, meaning it is not as contagious or deadly as other varieties of the disease. Such strains are still a concern to agriculture and health officials because they can mutate into more dangerous, highly pathogenic forms of the virus. Japan has banned imports of poultry from the area around the infected farm, and Kazakhstan has banned imports from Jasper County unless they are heat-treated to a required temperature, according to United States Department of Agriculture notices. In January, an Indiana turkey flock was thought to have become infected with highly pathogenic flu when a less dangerous strain mutated. More than 400,000 birds around the infected farm were eventually culled to contain the outbreak. Last year, almost 50 million chickens and turkeys died in the United States because they were infected with a fast-moving outbreak of highly pathogenic bird flu or killed to contain the disease. Birds from the infected Missouri flock will not enter the food system, according to the USDA. In some outbreaks of low pathogenic flu, infected poultry can be slaughtered for meat if they have time to recover from the disease and test negative for it. However, the Missouri flock was a week away from going to slaughter when it was infected and there was not enough time for that process, the USDA said. The agency said it is treating the Missouri infection as it would any other low patfor that process, the USDA said. The agency said it is treating the Missouri infection as it would any other low pathogenic flu case. Wild birds are thought to spread the virus to farms through feces and feathers dropped from the air. The strain found in Missouri had its lineage in North American wild birds, officials said. culled from Reuters.com

Macaques Are Learning to Communicate with Touch-screens.

Akita, a 10-year-old Japanese macaque, sits in a glass booth calmly tapping away as colored dots flash on a video touch-screen anchored to a wall in front of him. Red, blue, yellow – he picks the dots in the requisite order, then grabs for his reward: fresh blueberries that pop out of a tube onto the floor next to him. Akita is one of eight adult Japanese macaques at the Lincoln Park Zoo in Chicago being trained to use a touch-screen. For now, he’s mastering simple sequencing tasks. But soon, researchers will start him on new exercises aimed ultimately at getting inside his head—finding out what he and the other macaques think and feel about their life in the zoo. A death or birth among their troop? Too many noisy visitors pressed up to the glass in front of them? Researchers hope to find out how these things affect the animals so that they can adjust animal care in response. Touch-screens, they hope, will provide a way to do this. “The goal is to evaluate and enhance their welfare,” says Katherine Cronin, lead research scientist for the zoo’s macaque project, which she believes to be unique to North America. Melissa Bateson, a professor of ethology at Newcastle University in the United Kingdom, has studied ways to communicate with animals and consulted with Cronin. Over the past decade, she says, animal welfare scientists have tried to adapt tasks used to measure emotions in humans to animals, but the process has been “quite laborious,” with a person needed to interact with the animal, offer it choices and record its behavior. “Translation of these tasks to a touch-screen that can offer choices and record data automatically would be a great advance,” she says, and “would pave the way for more widespread use of these novel approaches in applied settings such as zoos.” The research has helped Cronin and her team glean insights into the monkeys’ social environment—a rigidly defined hierarchy that the macaques self-police. This means that the monkeys voluntarily come to the booths during training time (generally mid-day, five days a week) in their ranked order, with alpha Akita first. Even if the macaques don’t get to the point of being able to communicate their cares and woes to their keepers, the touch-screen training has helped enhance their daily lives. Cronin says that research shows engaging in tasks that challenge the monkeys’ minds is in itself “a way to improve their welfare and keep them stimulated, because they’re such smart, complex animals.” culled from discovermagazine.com

Yeast Can Now Produce THC, Marijuana’s Infamous Compound,cannabidiol .

Yeast, the sugar-gobbling microorganism that’s filled our bellies with beer and bread for millennia, has a new, increasingly important, role to play in society: serving as a therapeutic drug factory. In August, scientists announced they had genetically engineered yeast to produce the painkiller hydrocodone, and even before that breakthrough, modified yeast churned out the anti-malarial drug artemisinin. Now, scientists have customized yeast to create THC (the marijuana chemical that produces a “high”) and cannabidiol Biochemists from the Technical University in Dortmund, Germany, created a genetically-engineered yeast strain to produce very small amounts of THC or cannabidiol. Unlike normal yeast, however, these custom yeast have to be fed cannabigerolic acid, which is a precursor molecule to THC and cannabidiol. Using a molecular precursor as a starting point is a bit like reading a book from the middle chapters to its conclusion. Ideally, the entire process would start with simple sugars — or chapter 1 — rather than precursors to complete the entire chemical pathway that the marijuana plant does naturally. However, scientists believe they’ll get to that point and scale up production for industrial use in the near future, the New York Times reports. The team published its work with the yeast strain that produces THC in the journal Biotechnology Letters. They also created a separate strain that produces cannabidiol, but those data are yet to be published. Marijuana is chock full of molecular compounds that are fascinating to scientists. Synthetic THC is already available in pill form and it is used to ease nausea in cancer patients undergoing chemotherapy, or stimulate the appetites of people with H.I.V. or other infections. Cannabidiol, a compound that is not psychoactive, has shown potential to reduce the frequency of seizures in epileptic individuals. Yeast factories could help scale up production of these chemicals not just for therapy, but for research too. Producing marijuana’s constituent compounds in vast quantities would give researchers a supply of marijuana’s myriad chemicals to better understand how, or if, they work as advertised. Still, at the moment, the plant is far more efficient than the yeast — modern marijuana strains can contain more than 30 percent THC by dry weight. So there’s still a long way to go before THC-producing yeast change the landscape of cannabis research. Researchers will likely need to splice many more genes into species of yeast to complete the entire chemical reaction in a single strain. But at the rate that genetically-modified yeast research is advancing, it may not be a long wait. culled from science for the curious Discover.