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Daniel Cressey In 2013, Beau Kilmer took on a pretty audacious head count. Citizens in the state of Washington had just voted to legalize marijuana for recreational use, and the state's liquor control board, which would regulate the nascent industry, was anxious to understand how many people were using the drug — and importantly, how much they were consuming. The task was never going to be straightforward. Users of an illicit substance, particularly heavy users, often under-report the amounts they take. So Kilmer, co-director of the RAND Drug Policy Research Center in Santa Monica, California, led a team to develop a web-based survey that would ask people how often they had used cannabis in the past month and year. To help them gauge the amounts, the surveys included scaled pictures showing different quantities of weed. The survey, along with other data the team had collected, revealed a rift between perception and reality. Based on prior data, state officials had estimated use at about 85 tonnes per year; Kilmer's research suggested that it was actually double that, about 175 tonnes1. The take-home message, says Kilmer, was “we're going to have to start collecting more data”. Scientists around the world would echo that statement. Laws designed to legalize cannabis or lessen the penalties associated with it are taking effect around the world. They are sweeping the sale of the drug out of stairwells and shady alleys and into modern shopfronts under full view of the authorities. In 2013, Uruguay became the first nation to legalize marijuana trade. And several countries in Europe — Spain and Italy among them — have moved away from tough penalties for use and possession. Thirty-nine US states plus Washington DC have at least some provisions for medicinal use of the drug. Washington, Colorado, Alaska and Oregon have gone further, legalizing the drug for recreational consumption. A handful of other states including California and Massachusetts are expected to vote on similar recreational-use measures by the end of 2016. © 2015 Nature Publishing Group
Keyword: Drug Abuse
Link ID: 21315 - Posted: 08.19.2015
By Lisa Rapaport (Reuters Health) - U.S. teens who try electronic cigarettes may be more than twice as likely to move on to smoking conventional cigarettes as those who have never tried the devices, report researchers from the University of Southern California. The findings, published August 18 in JAMA, offer some of the best evidence yet at establishing a link between e-cigarettes and smoking, said Dr. Nancy Rigotti, an expert in tobacco research at Massachusetts General Hospital and author of an editorial accompanying the study. "Adolescent brains appear to be especially susceptible to becoming addicted to nicotine when exposed," Rigotti told Reuters Health in an email. About 2 million middle- and high-school students tried e-cigarettes in 2014, triple the number of teen users in 2013, the Centers for Disease Control and Prevention reported in April. The data sparked alarm among tobacco control advocates who fear e-cigarettes will create a new generation of nicotine addicts who may eventually switch to conventional cigarettes. Big tobacco companies, including Altria Group Inc, Lorillard Tobacco Co and Reynolds American Inc, are all developing e-cigarettes. The battery-powered devices feature a glowing tip and a heating element that turns liquid nicotine and other flavorings into a cloud of vapor that users inhale. An international review of published research by the Cochrane Review in December concluded that the devices could help smokers quit but said much of the existing evidence on e-cigarettes was thin. © 2015 Scientific American
Keyword: Drug Abuse
Link ID: 21314 - Posted: 08.19.2015
—By Chris Mooney It is still considered highly uncool to ascribe a person's political beliefs, even in part, to that person's biology: hormones, physiological responses, even brain structures and genes. And no wonder: Doing so raises all kinds of thorny, non-PC issues involving free will, determinism, toleration, and much else. There's just one problem: Published scientific research keeps going there, with ever increasing audacity (not to mention growing stacks of data). The past two weeks have seen not one but two studies published in scientific journals on the biological underpinnings of political ideology. And these studies go straight at the role of genes and the brain in shaping our views, and even our votes. First, in the American Journal of Political Science, a team of researchers including Peter Hatemi of Penn State University and Rose McDermott of Brown University studied the relationship between our deep-seated tendencies to experience fear—tendencies that vary from person to person, partly for reasons that seem rooted in our genes—and our political beliefs. What they found is that people who have more fearful disposition also tend to be more politically conservative, and less tolerant of immigrants and people of races different from their own. As McDermott carefully emphasizes, that does not mean that every conservative has a high fear disposition. "It's not that conservative people are more fearful, it's that fearful people are more conservative," as she puts it. I interviewed the paper's lead author, Peter Hatemi, about his research for my 2012 book The Republican Brain. Hatemi is both a political scientist and also a microbiologist, and as he stressed to me, "nothing is all genes, or all environment." These forces combine to make us who we are, in incredibly intricate ways. ©2015 Mother Jones
Helen Thomson Serious mood disorders such as bipolar may be the price humans have had to pay for our intelligence and creativity. That’s according to new research which links high childhood IQ to an increased risk of experiencing manic bipolar traits in later life. Researchers examined data from a large birth cohort to identify the IQ of 1,881 individuals at age eight. These same individuals were then assessed for manic traits at the age of 22 or 23. The statements they provided were part of a checklist widely used to diagnose bipolar disorder. Each person was given a score out of 100 related to how many manic traits they had previously experienced. Individuals who scored in the top 10% of manic features had a childhood IQ almost 10 points higher than those who scored in the lowest 10%. This correlation appeared strongest for those with high verbal IQ. “Our study offers a possible explanation for how bipolar disorder may have been selected through generations,” said Daniel Smith of the University of Glasgow , who led the study. “There is something about the genetics underlying the disorder that are advantageous. One possibility is that serious disorders of mood - such as bipolar disorder - are the price that human beings have had to pay for more adaptive traits such as intelligence, creativity and verbal proficiency.” Smith emphasises that as things stand, having a high IQ is only an advantage: “A high IQ is not a clear-cut risk factor for bipolar, but perhaps the genes that confer intelligence can get expressed as illness in the context of other risk factors, such as exposure to maternal influenza in the womb or childhood sexual abuse.” © 2015 Guardian News and Media Limited
By ANDREW POLLACK The first prescription drug to enhance women’s sexual drive won regulatory approval on Tuesday, clinching a victory for a lobbying campaign that had accused the Food and Drug Administration of gender bias for ignoring the sexual needs of women. The drug — Addyi from Sprout Pharmaceuticals — is actually the first drug approved to treat a flagging or absent libido for either sex. Viagra and other drugs available for men are approved to help achieve erections, or to treat certain deficiencies of the hormone testosterone, not to increase desire. Advocates who pressed for approval of Addyi, many of them part of a coalition called Even the Score, said that a drug to improve women’s sex lives was long overdue, given the many options available to men. “This is the biggest breakthrough for women’s sexual health since the pill,” said Sally Greenberg, executive director of the National Consumers League. But critics said the campaign behind Addyi had made a mockery of the system that regulates pharmaceuticals and had co-opted the women’s movement to pressure the F.D.A. into approving a drug that was at best minimally effective and could cause side effects like low blood pressure, fainting, nausea, dizziness and sleepiness. In announcing the approval, Dr. Janet Woodcock, a senior F.D.A. official, said the agency was “committed to supporting the development of safe and effective treatments for female sexual dysfunction.” The F.D.A. decision on Tuesday was not a surprise since an advisory committee of outside experts had recommended by a vote of 18 to 6 in June that the drug be approved, albeit with precautions required to try to limit the risks and ensure that it was not overused. © 2015 The New York Times Company
Keyword: Sexual Behavior
Link ID: 21311 - Posted: 08.19.2015
By Zoe Kleinman Technology reporter, BBC News More than 200 academics have signed an open letter criticising controversial new research suggesting a link between violent video games and aggression. The findings were released by the American Psychological Association. It set up a taskforce that reviewed hundreds of studies and papers published between 2005 and 2013. The American Psychological Association concluded while there was "no single risk factor" to blame for aggression, violent video games did contribute. "The research demonstrates a consistent relation between violent video game use and increases in aggressive behaviour, aggressive cognitions and aggressive affect, and decreases in pro-social behaviour, empathy and sensitivity to aggression," said the report. "It is the accumulation of risk factors that tends to lead to aggressive or violent behaviour. The research reviewed here demonstrates that violent video game use is one such risk factor." However, a large group of academics said they felt the methodology of the research was deeply flawed as a significant part of material included in the study had not been subjected to peer review. "I fully acknowledge that exposure to repeated violence may have short-term effects - you would be a fool to deny that - but the long-term consequences of crime and actual violent behaviour, there is just no evidence linking violent video games with that," Dr Mark Coulson, associate professor of psychology at Middlesex University and one of the signatories of the letter told the BBC. "If you play three hours of Call of Duty you might feel a little bit pumped, but you are not going to go out and mug someone." © 2015 BBC
Link ID: 21310 - Posted: 08.19.2015
Alexander Christie-Miller You could say they sent the first tweets. An ancient whistling language that sounds a little like birdsong has been found to use both sides of the brain – challenging the idea that the left side is all important for communicating. The whistling language is still used by around 10,000 people in the mountains of north-east Turkey, and can carry messages as far as 5 kilometres. Researchers have now shown that this language involves the brain’s right hemisphere, which was already known to be important for understanding music. Until recently, it was thought that the task of interpreting language fell largely to the brain’s left hemisphere. Onur Güntürkün of Ruhr University Bochum in Germany wondered whether the musical melodies and frequencies of whistled Turkish might require people to use both sides of their brain to communicate. His team tested 31 fluent whistlers by playing slightly different spoken or whistled syllables into their left and right ears at the same time, and asking them to say what they heard. The left hemisphere depends slightly more on sounds received by the right ear, and vice versa for the right hemisphere. By comparing the number of times the whistlers reported the syllables that had been played into either their right or left ear, they could tell how often each side of the brain was dominant. As expected, when the syllables were spoken, the right ear and left hemisphere were dominant 75 per cent of the time. But when syllables were whistled, the split between right and left dominance was about even. © Copyright Reed Business Information Ltd.
By Perri Klass, A little more than a year ago, the American Academy of Pediatrics issued a policy statement saying that all pediatric primary care should include literacy promotion, starting at birth. That means pediatricians taking care of infants and toddlers should routinely be advising parents about how important it is to read to even very young children. The policy statement, which I wrote with Dr. Pamela C. High, included a review of the extensive research on the links between growing up with books and reading aloud, and later language development and school success. But while we know that reading to a young child is associated with good outcomes, there is only limited understanding of what the mechanism might be. Two new studies examine the unexpectedly complex interactions that happen when you put a small child on your lap and open a picture book. This month, the journal Pediatrics published a study that used functional magnetic resonance imaging to study brain activity in 3-to 5-year-old children as they listened to age-appropriate stories. The researchers found differences in brain activation according to how much the children had been read to at home. Children whose parents reported more reading at home and more books in the home showed significantly greater activation of brain areas in a region of the left hemisphere called the parietal-temporal-occipital association cortex. This brain area is “a watershed region, all about multisensory integration, integrating sound and then visual stimulation,” said the lead author, Dr. John S. Hutton, a clinical research fellow at Cincinnati Children’s Hospital Medical Center. This region of the brain is known to be very active when older children read to themselves, but Dr. Hutton notes that it also lights up when younger children are hearing stories. What was especially novel was that children who were exposed to more books and home reading showed significantly more activity in the areas of the brain that process visual association, even though the child was in the scanner just listening to a story and could not see any pictures. © 2015 The New York Times Company
Every brain cell has a nucleus, or a central command station. Scientists have shown that the passage of molecules through the nucleus of a star-shaped brain cell, called an astrocyte, may play a critical role in health and disease. The study, published in the journal Nature Neuroscience, was partially funded by the National Institutes of Health (NIH). “Unexpectedly we may have discovered a hidden pathway to understanding how astrocytes respond to injury and control brain processes. The pathway may be common to many brain diseases and we’re just starting to follow it,” said Katerina Akassoglou, Ph.D., a senior investigator at the Gladstone Institute for Neurological Disease, a professor of neurology at the University of California, San Francisco, and a senior author of the study. Some neurological disorders are associated with higher than normal brain levels of the growth factor TGF-beta, including Alzheimer's disease and brain injury. Previous studies found that after brain injury, astrocytes produce greater amounts of p75 neurotrophin receptor (p75NTR), a protein that helps cells detect growth factors. The cells also react to TGF-beta by changing their shapes and secreting proteins that alter neuronal activity. Dr. Akassoglou’s lab showed that eliminating the p75NTR gene prevented hydrocephalus in mice genetically engineered to have astrocytes that produce higher levels of TGF-beta. Hydrocephalus is a disorder that fills the brain with excess cerebral spinal fluid. Eliminating the p75NTR gene also prevented astrocytes in the brains of the mice from forming scars after injuries and restored gamma oscillations, which are patterns of neuronal activity associated with learning and memory.
By Kate Kelland LONDON (Reuters) - Scientists have genetically modified mice to be super-intelligent and found they are also less anxious, a discovery that may help the search for treatments for disorders such as Alzheimer's, schizophrenia and post traumatic stress disorder (PTSD). Researchers from Britain and Canada found that altering a single gene to block the phosphodiesterase-4B (PDE4B) enzyme, which is found in many organs including the brain, made mice cleverer and at the same time less fearful. "Our work using mice has identified phosphodiesterase-4B as a promising target for potential new treatments," said Steve Clapcote, a lecturer in pharmacology at Britain's Leeds University, who led the study. He said his team is now working on developing drugs that will specifically inhibit PDE4B. The drugs will be tested first in animals to see whether any of them might be suitable to go forward into clinical trials in humans. In the experiments, published on Friday in the journal Neuropsychopharmacology, the scientists ran a series of behavioral tests on the PDE4B-inhibited mice and found they tended to learn faster, remember events longer and solve complex problems better than normal mice. The "brainy" mice were better at recognizing a mouse they had seen the previous day, the researchers said, and were also quicker at learning the location of a hidden escape platform.
Dean Burnett Yesterday, an article in the Entrepreneurs section of the Guardian purported to reveal a “cloth cap that could help treat depression”. This claim has caused some alarm in the neuroscience and mental health fields, so it’s important to look a little more closely at what the manufacturers are actually claiming. The piece in question concerns a product from Neuroelectrics: a soft helmet containing electrodes and sensors. According to the company’s website, it can be used to monitor brain activity (electroencephalography, or EEG), or administer light electrical currents to different areas of the brain in order to treat certain neurological and psychiatric conditions (known as transcranial direct current stimulation or tDCS). While this would obviously be great news to the millions of people who deal with such conditions every day, such claims should be treated with a considerable amount of caution. The fields of science dedicated to researching and, hopefully, treating serious brain-based problems like depression, stroke, personality disorder etc. work hard to find new and inventive methods for doing so, or refining and improving existing ones. Sometimes they succeed, but probably not as often as they’d like. The problem is that when a new development occurs or a new approach is found, it doesn’t automatically mean it’s widely applicable or even effective for everyone. The brain is furiously complicated. There is no magic bullet for brain problems [Note: you shouldn’t use bullets, magic or otherwise, when dealing with the brain]. © 2015 Guardian News and Media Limited
Link ID: 21305 - Posted: 08.18.2015
By NICHOLAS BAKALAR “Insanity Treated By Electric Shock” read the headline of an article published on July 6, 1940, in The New York Times. The article described “a new method, introduced in Italy, of treating certain types of mental disorders by sending an electric shock through the brain.” It was the first time that what is now called electroconvulsive therapy, or ECT, had been mentioned in The Times. The electric shock, the article said, “is produced by a small portable electric box which was invented in Italy by Professor Ugo Cerletti of the Rome University Clinic.” Dr. S. Eugene Barrera, the principal researcher on the project, “emphasized that hope for any ‘miracle cure’ must not be pinned on the new method.” On April 29, 1941, the subject came up again, this time in an article about a scientific meeting at which a professor of psychiatry at Northwestern reported “ ‘very promising instantaneous results’ in the recently developed electric shock method of relieving schizophrenic patients of their malady.” The treatment entered clinical practice fairly quickly. In October 1941, The Times reported on the opening of several new buildings at Hillside Hospital in Queens (today called Zucker Hillside Hospital). “The hospital has pioneered in the use of insulin and metrazol, and also in the electric shock treatment, which has proved useful in shortening the average stay of patients,” the article read. Over the years, ECT has had its ups and downs in the public imagination and in the pages of The Times. In an article on Nov. 25, 1980, the reporter Dava Sobel seemed to relegate it to another age. © 2015 The New York Times Company
Link ID: 21304 - Posted: 08.18.2015
By CLAIRE MARTIN The eyeglass lenses that Don McPherson invented were meant for surgeons. But through serendipity he found an entirely different use for them: as a possible treatment for colorblindness. Mr. McPherson is a glass scientist and an avid Ultimate Frisbee player. He discovered that the lenses he had invented, which protect surgeons’ eyes from lasers and help them differentiate human tissue, caused the world at large to look candy-colored — including the Frisbee field. At a tournament in Santa Cruz, Calif., in 2002, while standing on a grassy field dotted with orange goal-line cones, he lent a pair of glasses with the lenses to a friend who happened to be colorblind. “He said something to the effect of, ‘Dude, these are amazing,’ ” Mr. McPherson says. “He’s like, ‘I see orange cones. I’ve never seen them before.’ ” Mr. McPherson was intrigued. He said he did not know the first thing about colorblindness, but felt compelled to figure out why the lenses were having this effect. Mr. McPherson had been inserting the lenses into glasses that he bought at stores, then selling them through Bay Glass Research, his company at the time. Mr. McPherson went on to study colorblindness, fine-tune the lens technology and start a company called EnChroma that now sells glasses for people who are colorblind. His is among a range of companies that have brought inadvertent or accidental inventions to market. Such inventions have included products as varied as Play-Doh, which started as a wallpaper cleaner, and the pacemaker, discovered through a study of hypothermia. To learn more about color vision and the feasibility of creating filters to correct colorblindness, Mr. McPherson applied for a grant from the National Institutes of Health in 2005. He worked with vision scientists and a mathematician and computer scientist named Andrew Schmeder. They weren’t the first to venture into this industry; the history of glassmakers claiming to improve colorblindness is long and riddled with controversy. © 2015 The New York Times Company
Link ID: 21303 - Posted: 08.17.2015
A new clinical trial is set to begin in the United Kingdom using the powerful noses of dogs to detect prostate cancer in humans. While research has been done before, these are the first trials approved by Britain's National Health Service. The trials, at the Milton Keynes University Hospital in Buckinghamshire, will use animals from a nonprofit organization called Medical Detection Dogs, co-founded in 2008 by behavioral psychologist Claire Guest. "What we've now discovered is that lots of diseases and conditions — and cancer included — that they actually have different volatile organic compounds, these smelly compounds, that are associated with them," Guest tells NPR's Rachel Martin. "And dogs can smell them." The dogs offer an inexpensive, non-invasive method to accompany the existing blood tests for prostate cancer, which detect prostate-specific antigen, or PSA, Guest says. "It's a low false-negative but a very high false-positive, meaning that three out of four men that have a raised PSA haven't got cancer," she explains. "So the physician has a very difficult decision to make: Which of the four men does he biopsy? What we want to do is provide an additional test — not a test that stands alone but an additional test that runs alongside the current testing, which a physician can use as part of that patient's picture." The samples come to the dogs — the dogs never go to the patient. At the moment, our dogs would be screening about between a .5- to 1-ml drop of urine [or 1/5 to 1/10 teaspoon], so a very small amount. In the early days, of course, we know whether the samples have come from a patient with cancer or if the patient has another disease or condition, or is in fact healthy. © 2015 NPR
Keyword: Chemical Senses (Smell & Taste)
Link ID: 21302 - Posted: 08.17.2015
John von Radowitz , Press Association Psychologists have confirmed that playing violent video games is linked to aggressive and callous behaviour. A review of almost a decade of studies found that exposure to violent video games was a "risk factor" for increased aggression. But the same team of experts said there was insufficient evidence to conclude that the influence of games such as Call Of Duty and Grand Theft Auto led to criminal acts. The findings have prompted a call for more parental control over violent scenes in video games from the American Psychological Association (APA). The original version of Doom, released in 1993, was widely controversial for its unprecedented levels of graphic violence A report from the APA task force on violent media concludes: "The research demonstrates a consistent relation between violent video game use and increases in aggressive behaviour, aggressive cognitions and aggressive affect, and decreases in pro-social behaviour, empathy and sensitivity to aggression." The report said no single influence led a person to act aggressively or violently. Rather, it was an "accumulation of risk factors" that resulted in such behaviour. It added: "The research reviewed here demonstrates that violent video game use is one such risk factor." The APA has urged game creators to increase levels of parental control over the amount of violence video games contain.
Link ID: 21301 - Posted: 08.17.2015
Geoff Brumfiel Learning to make sounds by listening to others is a skill that helps make us human. But research now suggests a species of monkey may have evolved similar abilities. Marmosets have the capacity to learn calls from their parents, according to research published Thursday in the journal Science. The results mean that studying marmosets might provide insights into developmental disorders found in humans. It also suggests that vocal learning may be more widespread than many researchers thought. Many animals can link sounds with meaning. Dogs respond to simple calls; chimpanzees can even communicate with people using sign language. But the ability to hear a sound and mimic it is possessed by only a small number of species: primarily song birds and humans. "We didn't think that mammals and primates in particular — besides us — had any type of vocal learning," says Asif Ghazanfar, a neuroscientist at Princeton University who led the new study. Enter the small, adorable common marmoset. These fuzzy South American primates look more like squirrels than a monkey. "They're cute, and they smell. They wash themselves in their own urine," Ghazanfar says. "I'm not sure why they do that." But once you get over the stink, these little guys are interesting. Marmoset mommies always give birth to twins and they need help rearing them. So, unlike many mammal species, fathers lend a hand, along with siblings and other community members. Ghazanfar thinks all that child care is what gives marmosets another special trait: They're super talkative. "They're chattering nonstop," he says. "That is also very different from our close relatives the chimpanzees." © 2015 NPR
Carl Zimmer You are what you eat, and so were your ancient ancestors. But figuring out what they actually dined on has been no easy task. There are no Pleistocene cookbooks to consult. Instead, scientists must sift through an assortment of clues, from the chemical traces in fossilized bones to the scratch marks on prehistoric digging sticks. Scientists have long recognized that the diets of our ancestors went through a profound shift with the addition of meat. But in the September issue of The Quarterly Review of Biology, researchers argue that another item added to the menu was just as important: carbohydrates, bane of today’s paleo diet enthusiasts. In fact, the scientists propose, by incorporating cooked starches into their diet, our ancestors were able to fuel the evolution of our oversize brains. Roughly seven million years ago, our ancestors split off from the apes. As far as scientists can tell, those so-called hominins ate a diet that included a lot of raw, fiber-rich plants. After several million years, hominins started eating meat. The oldest clues to this shift are 3.3-million-year-old stone tools and 3.4-million-year-old mammal bones scarred with cut marks. The evidence suggests that hominins began by scavenging meat and marrow from dead animals. At some point hominins began to cook meat, but exactly when they invented fire is a question that inspires a lot of debate. Humans were definitely making fires by 300,000 years ago, but some researchers claim to have found campfires dating back as far as 1.8 million years. Cooked meat provided increased protein, fat and energy, helping hominins grow and thrive. But Mark G. Thomas, an evolutionary geneticist at University College London, and his colleagues argue that there was another important food sizzling on the ancient hearth: tubers and other starchy plants. © 2015 The New York Times Company
When the owl swooped, the “blind” mice ran away. This was thanks to a new type of gene therapy to reprogramme cells deep in the eye to sense light. After treatment, the mice ran for cover when played a video of an approaching owl, just like mice with normal vision. “You could say they were trying to escape, but we don’t know for sure,” says Rob Lucas of the University of Manchester, UK, co-leader of the team that developed and tested the treatment. “What we can say is that they react to the owl in the same way as sighted mice, whereas the untreated mice didn’t do anything.” This is the team’s best evidence yet that injecting the gene for a pigment that detects light into the eyes of blind mice can help them see real objects again. This approach aims to treat all types of blindness caused by damaged or missing rods and cones, the eye’s light receptor cells. Most gene therapies for blindness so far have concentrated on replacing faulty genes in rarer, specific forms of inherited blindness, such as Leber congenital amaurosis. Deep down The new treatment works by enabling other cells that lie deeper within the retina to capture light. While rod and cone cells normally detect light and convert this into an electrical signal, the ganglion and bipolar cells behind them are responsible for processing these signals and sending them to the brain. By giving these cells the ability to produce their own light-detecting pigment, they can to some extent compensate for the lost receptors, or so it seems.
Link ID: 21298 - Posted: 08.15.2015
By Robert F. Service Move over, poppies. In one of the most elaborate feats of synthetic biology to date, a research team has engineered yeast with a medley of plant, bacterial, and rodent genes to turn sugar into thebaine, the key opiate precursor to morphine and other powerful painkilling drugs that have been harvested for thousands of years from poppy plants. The team also showed that with further tweaks, the yeast could make hydrocodone, a widely used painkiller that is now made chemically from thebaine. “This is a major milestone,” says Jens Nielsen, a synthetic biologist at Chalmers University of Technology in Göteborg, Sweden. The work, he adds, demonstrates synthetic biology’s increasing sophistication at transferring complex metabolic pathways into microbes. By tweaking the yeast pathways, medicinal chemists may be able to produce more effective, less addictive versions of opiate painkillers. But some biopolicy experts worry that morphinemaking yeast strains could also allow illicit drugmakers to brew heroin as easily as beer enthusiasts home brew today—the drug is a simple chemical conversion from morphine. That concern is one reason the research team, led by Christina Smolke, a synthetic biologist at Stanford University in Palo Alto, California, stopped short of making a yeast strain with the complete morphine pathway; medicinal drug makers also primarily use thebaine to make new compounds. Synthetic biologists had previously engineered yeast to produce artemisinin, an antimalarial compound, but that required inserting just a handful of plant genes. To get yeast to make thebaine, © 2015 American Association for the Advancement of Science.
By James Gallagher Health editor, BBC News website Fat or carbs? Scientists have shed new light on which diet might be more effective at reducing fat Cutting fat from your diet leads to more fat loss than reducing carbohydrates, a US health study shows. Scientists intensely analysed people on controlled diets by inspecting every morsel of food, minute of exercise and breath taken. Both diets, analysed by the National Institutes of Health, led to fat loss when calories were cut, but people lost more when they reduced fat intake. Experts say the most effective diet is one people can stick to. It has been argued that restricting carbs is the best way to get rid of a "spare tyre" as it alters the body's metabolism. The theory goes that fewer carbohydrates lead to lower levels of insulin, which in turn lead to fat being released from the body's stores. "All of those things do happen with carb reduction and you do lose body fat, but not as much as when you cut out the fat," said lead researchers Dr Kevin Hall, from the US-based National Institute of Diabetes and Digestive and Kidney Diseases. Cutting down on carbohydrates might not be as effective after all, the study suggests In the study, 19 obese people were initially given 2,700 calories a day. Then, over a period of two weeks they tried diets which cut their calorie intake by a third, either by reducing carbohydrates or fat. The team analysed the amount of oxygen and carbon dioxide being breathed out and the amount of nitrogen in participants' urine to calculate precisely the chemical processes taking place inside the body. The results published in Cell Metabolism showed that after six days on each diet, those reducing fat intake lost an average 463g of body fat - 80% more than those cutting down on carbs, whose average loss was 245g. © 2015 BBC.
Link ID: 21296 - Posted: 08.15.2015