Chapter 5. The Sensorimotor System
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by Carl Zimmer Inside each of us is a miniature version of ourselves. The Canadian neurologist Wilder Penfield discovered this little person in the 1930s, when he opened up the skulls of his patients to perform brain surgery. He would sometimes apply a little electric jolt to different spots on the surface of the brain and ask his patients–still conscious–to tell him if they felt anything. Sometimes their tongues tingled. Other times their hand twitched. Penfield drew a map of these responses. He ended up with a surreal portrait of the human body stretched out across the surface of the brain. In a 1950 book, he offered a map of this so-called homunculus. For brain surgeons, Penfield’s map was a practical boon, helping them plan out their surgeries. But for scientists interested in more basic questions about the brain, it was downright fascinating. It revealed that the brain organized the sensory information coming from the skin into a body-like form. There were differences between the homunculus and the human body, of course. It was as if the face had been removed from the head and moved just out of reach. The area that each body part took up in the brain wasn’t proportional to its actual size. The lips and index finger were gigantic, for instance, while the forearm barely took up less space than the tongue. That difference in our brains is reflected in our nerve endings. Our fingertips are far more sensitive than our backs. We simply don’t need to make fine discriminations with our backs. But we use our hands for all sorts of things–like picking up objects or using tools–that demand that sort of sensory power.
Keyword: Pain & Touch
Link ID: 18407 - Posted: 07.25.2013
Recycling is not only good for the environment, it’s good for the brain. A study using rat cells indicates that quickly clearing out defective proteins in the brain may prevent loss of brain cells. Results of a study in Nature Chemical Biology suggest that the speed at which damaged proteins are cleared from neurons may affect cell survival and may explain why some cells are targeted for death in neurodegenerative disorders. The research was supported by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health. One of the mysteries surrounding neurodegenerative diseases is why some nerve cells are marked for destruction whereas their neighbors are spared. It is especially puzzling because the protein thought to be responsible for cell death is found throughout the brain in many of these diseases, yet only certain brain areas or cell types are affected. In Huntington’s disease and many other neurodegenerative disorders, proteins that are misfolded (have abnormal shapes), accumulate inside and around neurons and are thought to damage and kill nearby brain cells. Normally, cells sense the presence of malformed proteins and clear them away before they do any damage. This is regulated by a process called proteostasis, which the cell uses to control protein levels and quality. In the study, Andrey S. Tsvetkov and his colleagues showed that differences in the rate of proteostasis may be the clue to understanding why certain nerve cells die in Huntington’s, a genetic brain disorder that leads to uncontrolled movements and death.
Link ID: 18403 - Posted: 07.23.2013
By Melinda Wenner Moyer Many studies over the past decade have pointed to pesticides as a potential cause of Parkinson's disease, a neurodegenerative condition that impairs motor function and afflicts a million Americans. Yet scientists have not had a good idea of how these chemicals harm the brain. A recent study suggests a possible answer: pesticides may inhibit a biochemical pathway that normally protects dopaminergic neurons, the brain cells selectively attacked by the disease. Preliminary research also indicates that this pathway plays a role in Parkinson's even when pesticides are not involved, providing an exciting new target for drug development. Past studies have shown that a pesticide called benomyl, which lingers in the environment despite having been banned in the U.S. in 2001 because of health concerns, inhibits the chemical activity of aldehyde dehydrogenase (ALDH) in the liver. Researchers at the University of California, Los Angeles, U.C. Berkeley, the California Institute of Technology and the Greater Los Angeles Veterans Affairs Medical Center wondered whether the pesticide might also affect levels of ALDH in the brain. ALDH's job is to break down DOPAL, a naturally forming toxic chemical, rendering it harmless. To find out, the researchers exposed different types of human brain cells—and, later, whole zebra fish—to benomyl. They found that it “killed almost half of the dopamine neurons while leaving all other neurons tested intact,” according to lead author and U.C.L.A. neurologist Jeff Bronstein. When they zeroed in on the affected cells, they confirmed that the benomyl was indeed inhibiting the activity of ALDH, which in turn spurred the toxic accumulation of DOPAL. Interestingly, when the scientists lowered DOPAL levels using a different technique, benomyl did not harm the dopamine neurons, a finding that suggests that the pesticide kills these neurons specifically because it allows DOPAL to build up. © 2013 Scientific American,
Here’s yet another reason to get off the couch: new research findings suggest that regularly breaking a sweat may lower the risk of having a stroke. A stroke can occur when a blood vessel in the brain gets blocked. As a result, nearby brain cells will die after not getting enough oxygen and other nutrients. A number of risk factors for stroke have been identified, including smoking, high blood pressure, diabetes and being inactive. For this study, published in the journal Stroke, Michelle N. McDonnell, Ph.D., from the University of South Australia, Adelaide and her colleagues obtained data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. REGARDS is a large, long-term study funded by the NIH National Institute of Neurological Disorders and Stroke (NINDS) to look at the reasons behind the higher rates of stroke mortality among African-Americans and other residents living in the Southeastern United States. “Epidemiological studies such as REGARDS provide an important opportunity to explore race, genetics, environmental, and lifestyle choices as stroke risk factors,” said Claudia Moy, Ph.D., program director at NINDS. Over 30,000 participants supplied their medical history over the phone. The researchers also visited them to obtain health measures such as body mass index and blood pressure. At the beginning of the study, the researchers asked participants how many times per week they exercised vigorously enough to work up a sweat. The researchers contacted participants every six months to see if they had experienced a stroke or a mini-stroke known as a transient ischemic attack (TIA). To confirm their responses, the researchers reviewed participants’ medical records.
Link ID: 18393 - Posted: 07.20.2013
By GRETCHEN REYNOLDS Two newly published studies investigate the enticing possibility that we might one day be able to gain the benefits of exercise by downing a pill, rather than by actually sweating. But while some of the research holds out promise for an effective workout pill, there remains the question of whether such a move is wise. The more encouraging of the new studies, which appears this week in Nature Medicine, expands on a major study published last year in Nature. In that study, researchers at the Scripps Research Institute in Jupiter, Fla., reported that a compound they had created and injected into obese mice increased activation of a protein called REV-ERB, which is known to partially control animals’ circadian rhythms and internal biological clocks. The injected animals lost weight, even on a high-fat diet, and improved their cholesterol profiles. Unexpectedly, the treated mice also began using more oxygen throughout the day and expending about 5 percent more energy than untreated mice, even though they were not moving about more than the other animals. In fact, in most cases, they were more physically lazy and inactive than they had been before the injections. The drug, it seemed, was providing them with a workout, minus the effort. Intrigued, the Scripps scientists, in conjunction with researchers from the Pasteur Institute in France and other institutions, set out to see what their compound might be doing inside muscles to provide this ersatz exercise. They knew that their drug increased the potency of the REV-ERB protein, but no one yet knew what REV-ERB actually does in muscles. So they began by developing a strain of mice that could not express very much of the protein in their muscle cells. Copyright 2013 The New York Times Company
Link ID: 18384 - Posted: 07.18.2013
By PERRI KLASS, M.D. My patient was missing a lot of middle school because of headaches. Her physical exam was completely normal, and the symptoms sounded like migraine — she had a throbbing sensation on both sides of her head, was more comfortable when the room was dark, and felt much better if she took ibuprofen. I asked her to keep a “headache diary,” noting when the headaches came, how long they lasted, what made them better or worse. Instead, that evening she and her mother went to the emergency room, where a head CT scan was done. The scan was normal, the diagnosis migraine, and mother and daughter felt better. They had been worried the girl might have had a brain tumor. Headaches are common in children, interfering with school, with activities, with life in general. Many children get migraines, even some too young to describe their symptoms: Sometimes they hit themselves in the head in reaction to the pain. Other children get “tension-type” headaches, sometimes related to muscle tightness or to stress. Children’s headaches can be related to ailments, from allergies to ear infections to sinus problems, and most of the time they don’t indicate a dangerous illness. But for many parents, the shadow of a terrible diagnosis lurks in the corner of the darkened room where a headachy child is lying with a cool cloth on her brow. Sometimes, children with headaches need neuroimaging — brain CTs or M.R.I.’s. But recently several large studies have raised concerns about CT scans done on children because the radiation from these scans can increase the risk of eventually developing cancer, though that overall risk is still very small. Copyright 2013 The New York Times Company
Keyword: Pain & Touch
Link ID: 18360 - Posted: 07.09.2013
Oxytocin, the naturally occuring human hormone linked to bonding with a newborn and romantic partner, could also help improve mood after rejection, a laboratory study suggests. When scientists in Montreal gave 100 students either oxytocin or a placebo through a nose spray and then tried to snub them in a conversation, feelings of trust were higher in the hormone group. But the hormone had no effect among those who weren't emotionally charged up by the social rejection of having researchers posing as students disagree, interrupt or ignore them. "Instead of the traditional 'fight or flight' response to social conflict where people get revved up to respond to a challenge or run away from it, oxytocin may promote the 'tend and befriend' response where people reach out to others for support after a stressful event. That can, in turn, strengthen social bonds and may be a healthier way to cope," study author Mark Ellenbogen said in a release. For a decade, researchers have speculated that oxytocin, known as the love hormone, motivates people to seek out social support to respond to challenges and blunt the negative hit of stress. Ellenbogen's team said its study offers the first experimental support of the idea that oxytocin motivates us to strengthen social bonds during times of distress. © CBC 2013
It only takes one bad apple to spoil the bunch, and the same may be true of certain proteins in the brain. Studies have suggested that just one rogue protein (in this case, a protein that is misfolded or shaped the wrong way) can act as a seed, leading to the misfolding of nearby proteins. According to an NIH-funded study, various forms of these seeds — originating from the same protein — may lead to different patterns of misfolding that result in neurological disorders with unique sets of symptoms. “This study has important implications for Parkinson’s disease and other neurodegenerative disorders,” said National Institute of Neurological Disorders and Stroke (NINDS) Director Story Landis, Ph.D. “We know that among patients with Parkinson’s disease, there are variations in the way that the disorder affects the brains. This exciting new research provides a potential explanation for why those differences occur.” An example of such a protein is alpha-synuclein, which can accumulate in brain cells, causing synucleinopathies, multiple system atrophy, Parkinson’s disease, Parkinson’s disease with dementia (PDD), and dementia with Lewy bodies (DLB). In addition, misfolded proteins other than alpha-synuclein sometimes aggregate, or accumulate, in the same brains. For example, tau protein collects into aggregates called tangles, which are the hallmark of Alzheimer’s disease and are often found in PDD and DLB brains. Findings from this study raise the possibility that different structural shapes, or strains, of alpha-synuclein may contribute to the co-occurrence of synuclein and tau accumulations in PDD or DLB.
By SABRINA TAVERNISE PORTSMOUTH, Ohio — Prescription pain pill addiction was originally seen as a man’s problem, a national epidemic that began among workers doing backbreaking labor in the coal mines and factories of Appalachia. But a new analysis of federal data has found that deaths in recent years have been rising far faster among women, quintupling since 1999. More women now die of overdoses from pain pills like OxyContin than from cervical cancer or homicide. And though more men are dying, women are catching up, according to the analysis by the Centers for Disease Control and Prevention. And the problem is hitting white women harder than black women, and older women harder than younger ones. In this Ohio River town on the edge of Appalachia, women blamed the changing nature of American society. The rise of the single-parent household has thrust immense responsibility on women, who are not only mothers, but also, in many cases, primary breadwinners. Some who described feeling overwhelmed by their responsibilities said they craved the numbness that drugs bring. Others said highs made them feel pretty, strong and productive, a welcome respite from the chaos of their lives. “I thought I was supermom,” said Crystal D. Steele, 42, a recovering addict who said she began to take medicine for back pain she developed working at Kentucky Fried Chicken. “I took one kid to football, the other to baseball. I went to work. I washed the car. I cleaned the house. I didn’t even know I had a problem.” © 2013 The New York Times Company
By C. CLAIBORNE RAY Q. What effect does the barometric pressure have on humans? Can it cause headaches and other discomforts? A. Differences in air pressure because of the weather or changes in altitude can have noticeable effects on the human body, though some people are more sensitive than others. Low barometric pressure can cause headaches by creating a pressure difference between the surrounding atmosphere and the sinuses, which are filled with air, said Dr. Matthew Fink, neurologist in chief at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. That leads to distended sinuses, especially if there is any congestion or blockage. “The same thing can happen with joints in people who have arthritis,” Dr. Fink said, with the low pressure associated with a coming storm aggravating joint pains in some. “High barometric pressure does not usually cause a problem, unless it is extreme,” he said. For example, water pressure can cause serious problems for a scuba diver because nitrogen dissolves in the blood when it is under pressure for some time. When the pressure is released as a diver ascends too quickly, the gas expands into bubbles; the resulting organic distress, often called the bends, can be fatal. One of the most noticeable effects of shifting air pressure occurs when a plane changes altitude rapidly. As expanding or contracting air in the inner ear equalizes its pressure with the surrounding atmosphere, ear popping and pain are common. © 2013 The New York Times Company
Keyword: Pain & Touch
Link ID: 18335 - Posted: 07.02.2013
Brendan Maher Hugh Rienhoff says that his nine-year-old daughter, Bea, is “a fire cracker”, “a tomboy” and “a very sassy, impudent girl”. But in a forthcoming research paper, he uses rather different terms, describing her hypertelorism (wide spacing between the eyes) and bifid uvula (a cleft in the tissue that hangs from the back of the palate). Both are probably features of a genetic syndrome that Rienhoff has obsessed over since soon after Bea’s birth in 2003. Unable to put on much muscle mass, Bea wears braces on her skinny legs to steady her on her curled feet. She is otherwise healthy, but Rienhoff has long worried that his daughter’s condition might come with serious heart problems. Rienhoff, a biotech entrepreneur in San Carlos, California, who had trained as a clinical geneticist in the 1980s, went from doctor to doctor looking for a diagnosis. He bought lab equipment so that he could study his daughter’s DNA himself — and in the process, he became a symbol for the do-it-yourself biology movement, and a trailblazer in using DNA technologies to diagnose a rare disease (see Nature 449, 773–776; 2007). “Talk about personal genomics,” says Gary Schroth, a research and development director at the genome-sequencing company Illumina in San Diego, California, who has helped Rienhoff in his search for clues. “It doesn’t get any more personal than trying to figure out what’s wrong with your own kid.” Now nearly a decade into his quest, Rienhoff has arrived at an answer. Through the partial-genome sequencing of his entire family, he and a group of collaborators have found a mutation in the gene that encodes transforming growth factor-β3 (TGF-β3). Genes in the TGF-β pathway control embryogenesis, cell differentiation and cell death, and mutations in several related genes have been associated with Marfan syndrome and Loeys–Dietz syndrome, both of which have symptomatic overlap with Bea’s condition. The mutation, which has not been connected to any disease before, seems to be responsible for Bea’s clinical features, according to a paper to be published in the American Journal of Medical Genetics. © 2013 Nature Publishing Group,
by Katia Moskvitch In the days before GPS, we needed both a compass and a map to navigate. Migrating birds are no different. Studies have suggested that the animals rely on an internal map and compass to traverse large distances, though just where these senses reside is unclear. Now, scientists say they have the strongest evidence yet that map sense is associated with the beak. Researchers have long suspected that migrating birds navigate by sensing Earth's magnetic field. The idea was that their beaks, which contain a lot of iron, worked like real magnets, with the metal aligning itself relative to the field. Supposedly, the so-called trigeminal nerve transmitted this information to the brain. But in 2009, a team led by Henrik Mouritsen of the University of Oldenburg in Germany cut the trigeminal nerve in several European robins and found that the animals still oriented perfectly. In lab-based experiments, the birds were able to locate the natural and artificial magnetic north. It seemed that the beak played no role in the compass sense. The finding gave support to another hypothesis, one that suggested that the inner compass was instead a magnetism-sensing chemical reaction in the birds' eyes. But Mouritsen's team was still convinced that the beak had to be involved in the magnetosense in some way, and it decided to do another test. In 2010 and 2011, the scientists captured 57 Eurasian reed warblers near Kaliningrad, Russia. Every spring, these birds migrate northeast to their breeding grounds in southern Scandinavia, up to 1000 kilometers away. Once again, the scientists snapped the trigeminal nerve, in half of the birds. But then they also moved all 57 birds 1000 kilometers to the east, where the magnetic field differs from their home site, and released them. © 2010 American Association for the Advancement of Science
Keyword: Animal Migration
Link ID: 18327 - Posted: 06.29.2013
Sid Perkins Sporting feats such as baseball's 100-mile-per-hour fastball are made possible by a suite of anatomical features that appeared in our hominin ancestors about 2 million years ago, a video study of college athletes suggests. And this ability to throw projectiles may have been crucial for human hunting, which in turn may have had a vital role in our evolution. “Throwing projectiles probably enabled our ancestors to effectively and safely kill big game,” says Neil Roach, a biological anthropologist at George Washington University in Washington DC, who led the work. Eating more calorie-rich meat and fat would have helped early hominins' brains and bodies to grow, enabling our ancestors to expand into new regions of the world, he suggests. The study is published today in Nature1. Although some primates occasionally throw objects, and with a fair degree of accuracy, only humans can routinely hurl projectiles with both speed and accuracy, says Roach. Adult male chimpanzees can throw objects at speeds of around 30 kilometres per hour, but even a 12-year-old human can pitch a baseball three times faster than that, he notes. In fact, the quickest motion that the human body produces — rotation of the humerus, the long bone in the upper arm, at a rate that is briefly equivalent to 25 full rotations in a single second — occurs while a person is throwing a projectile. © 2013 Nature Publishing Group,
By Meghan Rosen Paralyzed rats can now decide for themselves when it’s time to take a leak. Animals in a new study regained bladder control thanks to a new treatment that coaxes severed nerves to grow. Instead of dribbling out urine, the rodents squeezed out shots of pee almost as well as healthy rats do, researchers report June 25 in the Journal of Neuroscience. The study is the first to regenerate nerves that restore bladder function in animals with severely injured spinal cords. “This is a very big deal,” says neurologist John McDonald of the Kennedy Krieger Institute in Baltimore, Md. If the treatment works in people with spinal cord injuries, he says, “it would change their lives.” Unlike paralyzed rats, severely paralyzed humans can’t leak urine to relieve a full bladder. Unless injured people are fitted with a catheter, urine backs up into the kidneys. “These people get kidney failure all the time,” says study leader Jerry Silver, a neuroscientist at Case Western Reserve University in Cleveland. “It’s a terrible problem. If they didn’t have the catheter, they would die.” Some of the worst spinal cord injuries sever the bundle of nerve cells that reach from a mammal’s brain down through the vertebrae. The neurons can’t just grow back. Instead, the cells’ stumps get stuck in a gummy thicket of scar tissue that forms around the wound. © Society for Science & the Public 2000 - 2013
by Mara Hvistendahl and Martin Enserink A mysterious group of viruses known for their circular genome has been detected in patients with severe disease on two continents. In papers published independently this week, researchers report the discovery of agents called cycloviruses in Vietnam and in Malawi. The studies suggest that the viruses—one of which also widely circulates in animals in Vietnam—could be involved in brain inflammation and paraplegia, but further studies are needed to confirm a causative link. The discovery in Vietnam grew out of a frustrating lack of information about the causes of some central nervous system (CNS) infections such as encephalitis and meningitis, which can be fatal or leave lasting damage. "There are a lot of severe cases in the hospitals here, and very often we can't come to a diagnosis," says H. Rogier van Doorn, a clinical virologist with the Oxford University Clinical Research Unit in the Hospital for Tropical Diseases, Ho Chi Minh City. Extensive diagnostic tests turn up pathogens in only about half of patients with such infections, he says. Van Doorn and colleagues in Vietnam and at the University of Amsterdam's Academic Medical Center hoped that they might uncover new pathogens using a powerful new technique called next-generation sequencing. The group sequenced all the genetic material in cerebrospinal fluid (CSF) samples taken from more than 100 patients with undiagnosed CNS infections. One sample batch returned a promising lead: a viral sequence belonging to the Circoviridae family. © 2010 American Association for the Advancement of Science
Keyword: Movement Disorders
Link ID: 18311 - Posted: 06.25.2013
By Judith Graham, A year ago, Bernard Belisle was in a bad way. Pain throbbed in his legs all day, every day, and he was angry and irritable much of the time. Then, he enrolled in a novel study on preventing depression in older adults at the University of Pittsburgh Medical Center. Belisle says the move has changed his life. While this 73-year-old still has pain, he’s less oppressed by it after four months of therapy that taught him new ways to adapt to his osteoarthritis. “My pain is still there, but I can manage it better and I have a much more positive attitude,” says Belisle, whose emotional response to his chronic pain had put him at risk of becoming depressed. “If I feel I’m becoming upset these days, I stop and go on to something else,” he said. “I take more breaks, and I don’t take on more than I can handle.” The Pittsburgh investigation is the largest effort to explore whether helping older adults cope with their illnesses can forestall major depression, an underrecognized and undertreated mental health problem that often has a dramatic impact on seniors’ overall health. “It’s a vicious cycle: Pain can make people feel hopeless and helpless, which leads to depression, which can lead to [fitness] deconditioning, fatigue, worse sleep at night, which then amplifies pain and just perpetuates the cycle,” said Jordan Karp, who is heading up part of the study. © 1996-2013 The Washington Post
The paralyzing syndrome Guillain-Barré syndrome isn't linked to receiving common vaccines, according to a U.S. study. Concerns about the association of Guillain-Barré syndrome with vaccines have "flourished" since there was a hint of an increased risk after the 1976 swine flu vaccine campaign. It hasn’t been clearly linked since then. The syndrome is an acute inflammatory disease that results in destruction of a nerve’s myelin sheath and some nerves, which in severe cases can progress to complete paralysis and even death. Researchers from the U.S. Centers for Disease Control and Prevention and Kaiser Permanente Vaccine Study Center in Oakland, Calif. looked back at cases of GBS over 13 years in the state that were confirmed by a neurologist who reviewed the medical records. In the 13-year study period 415 patients were confirmed with GBS only 25 had received a vaccine within six weeks before onset of the disease. "In summary, this study did not find any association between influenza vaccine or any other vaccine and development of GBS within six weeks following vaccination," Dr. Roger Baxter, co-director of the Kaiser Permanente Vaccine Study Center and his co-authors concluded in Monday's online issue of Clinical Infectious Diseases. © CBC 2013
By Amy Mathews Amos, My symptoms started in January 2008, with deep pain in my bladder and the sense that I had to urinate constantly. I was given a diagnosis of interstitial cystitis, a chronic bladder condition with no known cure. But in the following months, pain spread to my thighs, knees, hips, buttocks, abdomen and back. By the time my condition was properly diagnosed three years later, I had seen two urogynecologists, three orthopedists, six physical therapists, two manual therapists, a rheumatologist, a neurologist, a chiropractor and a homeopath. What was wrong? Something completely unexpected, given my symptoms: myofascial pain syndrome, a condition caused by muscle fibers that contract but don’t release. That constant contraction creates knots of taut muscle, or trigger points, that send pain throughout the body, even to parts that are perfectly healthy. Most doctors have never heard of myofascial pain syndrome and few know how to treat it. In my case, trigger points in my pelvic floor — the bowl of muscle on the bottom of the pelvis — referred pain to my bladder. Points along my thighs pulled on my knee joints, creating sharp pain when I walked. Points in my hips, buttocks and abdomen threw my pelvis and lower spine out of alignment, pushing even more pain up my back. The pain was so severe at times that I could sit for only brief periods. “Why didn’t anybody know this?” I asked my doctor, Timothy Taylor, soon after he correctly diagnosed the reason for my pain. “Because doctors don’t specialize in muscles,” he said. “It’s the forgotten organ.” © 1996-2013 The Washington Post
By E. Paul Zehr As an infant, the Man Of Steel escaped Krypton’s red sun in a rocket lovingly prepared for him by his parents. Kal-L (but more commonly known as Kal-El) arrived under our yellow sun in Smallville to eventually become Clark Kent. Since his debut in Action Comics #1 in June of 1938, Superman has accumulated a pretty long list of “super abilities”. For me, though, I really like the list of his abilities that come from the 1940s radio serials. This was back when Superman was described as “faster than a speeding bullet, more powerful than a locomotive, and able to leap tall buildings in a single bound”. These descriptions all have to do with super-strength when you get right down to it. And with this summer’s “Man of Steel” Superman re-boot, super-strength is the focus of this post. I have to admit I’ve always found the explanation for Superman’s powers to be, well, a bit dubious. He has his powers because of our yellow sun. That is, because he was from a red sun planet (Krypton) somehow the yellow sun of Earth unleashes some inner super power mechanism that gives Superman all his…super-ness. Of course it’s a bit pure escapist fun. But what if there actually was something to that, though? I don’t mean something to the “yellow sun / red sun” stuff. You can just check in with our “friendly neighborhood physics” professor Jim Kakalios and his bok “Physics of Superheroes” for the real deal on that one. I mean rather the unleashing of some inner mechanism bit. What if something inside the human body could be unleashed—like removing the shackles from Hercules—and allow for dramatically increased strength? © 2013 Scientific American
by Trisha Gura A rare genetic disease may be going to the dogs. About six in 100,000 babies are born with centronuclear myopathy, which weakens skeletal muscles so severely that children have trouble eating and breathing and often die before age 18. Now, by discovering a very similar condition in canines, researchers have a means to diagnose the disease, unravel its molecular intricacies, and target new therapies. The story began when Jocelyn Laporte, a geneticist at the Institute of Genetics and Molecular and Cellular Biology in Strasbourg, France, uncovered the genetic roots of an odd form of centronuclear myopathy that showed up in a Turkish family. Three children, two of them fraternal twins, were born normal. Then, at the age of 3-and-a-half, they grew progressively and rapidly ill. (Most forms of the illness do not come on so suddenly.) The twins died by the age of 9. Their younger brother recently reached the same age but is very ill. Investigators traced the problem to a mutation in a gene called BIN1, which makes a protein that helps shape the muscle so that it can respond to nerve signals that initiate muscle contraction. To find out how mutations in this gene could lead to such dire consequences, other researchers tried to genetically engineer mice models. But deleting the BIN1 gene failed to recreate the disease in mice, so the researchers had to look elsewhere. Laporte's team joined with geneticist and veterinarian Laurent Tiret, at the Alfort School of Veterinary Medicine in Paris, to tap a network of vets in the United States, United Kingdom, Canada, Australia, and France. The idea was to track down and analyze dogs that had spontaneously acquired a similar condition. Because of their longer lifespans and larger size, the canines could model how the disease progresses and might respond to new therapies. © 2010 American Association for the Advancement of Science