Links for Keyword: Muscles

Follow us on Facebook or subscribe to our mailing list, to receive news updates. Learn more.


Links 1 - 20 of 71

Scott Hensley In a split vote, advisers to the Food and Drug Administration recommended that the agency approve the first gene therapy for Duchenne muscular dystrophy, the most common form of the genetic illness. The vote, 8 to 6, came after a day of testimony from speakers for Sarepta Therapeutics, the maker of the gene therapy called SRP-9001, FDA scientists and families whose children have Duchenne muscular dystrophy. The question before the panel was whether the benefits for the treatment outweigh the risks. While the FDA is not bound by the recommendations of its outside advisers, it usually follows them. The agency is expected to decide by the end of May. Gene therapy for muscular dystrophy stirs hopes and controversy Duchenne muscular dystrophy is the most common inherited neuromuscular disorder among children. It affects an estimated 10,000 to 12,000 children in the U.S. The genetic condition mainly afflicts boys and leads to progressive muscle damage, loss of ability to movement and eventually death. Sarepta's treatment involves a single infusion of viruses that has been genetically modified to carry a gene to patients' muscles to produce a miniature version of a protein called dystrophin. Patients with Duchenne muscular dystrophy are missing the muscle-protecting protein or don't make enough of it. While not a cure, Sarepta argues that its "micro-dystrophin" treatment can help slow the progression of the disease. The company's request for approval rested mainly on how much micro-dystrophin the treatment produces in patients' muscles instead of waiting for clear, real-world evidence that it's actually helping patients. © 2023 npr

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 28780 - Posted: 05.13.2023

By Lisa Sanders, M.D. The 22-year-old man struggled to get out of bed. The E.M.T.s were just outside his door, if he could only get there. The previous day he felt that he was coming down with something. Normally he never took naps, but that afternoon, he returned from class feeling completely wiped out and slept long and hard. Yet when he awoke, he felt even worse. Every muscle was sore. He felt feverish. This must be the flu, he told himself. He had the flu shot before starting school that year, but of course no vaccine is 100 percent effective. He spent the rest of that afternoon in bed, too tired and in too much pain to even get up to join his partner for dinner. When he awoke in the middle of the night to go to the bathroom, he was so weak and sore he could hardly sit up. He maneuvered to the edge of the bed and, using the headboard, pulled himself to his feet, but his partner had to help him get to the bathroom. Once he was there, the urine he produced was startlingly dark — the color of Coca-Cola. The next day he felt no better. His partner wanted to stay home with him, but he hurried her off to work. It’s just the flu, he assured her. But as the morning wore on, he started to worry. He called his parents, who were both nurses. They were worried too; influenza can be bad. When he got the same message from a doctor back home in New York, he started wondering if he should go to the hospital. He’d never been this sick before. © 2021 The New York Times Company

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 27904 - Posted: 07.14.2021

Jon Hamilton This is the story of a fatal genetic disease, a tenacious scientist and a family that never lost hope. Conner Curran was 4 years old when he was diagnosed with Duchenne Muscular Dystrophy, a genetic disease that causes muscles to waste away. Conner's mother, Jessica Curran, remembers some advice she got from the doctor who made that 2015 diagnosis: "Take your son home, love him, take him on trips while he's walking, give him a good life and enjoy him because there are really not many options right now." Five years later, Conner is not just walking, but running faster than ever, thanks to an experimental gene therapy that took more than 30 years to develop. Conner was the first child to receive the treatment — a single infusion designed to fix the genetic mutation that was gradually causing his muscles cells to die. The treatment can't bring back the cells he's lost (he remains smaller and weaker than his twin brother, Kyle), but it has allowed the muscle cells he still has to function better. Since Conner's treatment, eight other boys with Duchenne have received two different doses of the gene therapy. Preliminary results on six of them, tested a year after treatment, showed they, too, had improved strength and endurance at an age when boys with Duchenne usually become weaker. © 2020 npr

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: Development of the Brain
Link ID: 27387 - Posted: 07.27.2020

By Gretchen Reynolds When we start to lift weights, our muscles do not strengthen and change at first, but our nervous systems do, according to a fascinating new study in animals of the cellular effects of resistance training. The study, which involved monkeys performing the equivalent of multiple one-armed pull-ups, suggests that strength training is more physiologically intricate than most of us might have imagined and that our conception of what constitutes strength might be too narrow. Those of us who join a gym — or, because of the current pandemic restrictions and concerns, take up body-weight training at home — may feel some initial disappointment when our muscles do not rapidly bulge with added bulk. In fact, certain people, including some women and most preadolescent children, add little obvious muscle mass, no matter how long they lift. But almost everyone who starts weight training soon becomes able to generate more muscular force, meaning they can push, pull and raise more weight than before, even though their muscles may not look any larger and stronger. Scientists have known for some time that these early increases in strength must involve changes in the connections between the brain and muscles. The process appears to involve particular bundles of neurons and nerve fibers that carry commands from the brain’s motor cortex, which controls muscular contractions, to the spinal cord and, from there, to the muscles. If those commands become swifter and more forceful, the muscles on the receiving end should respond with mightier contractions. Functionally, they would be stronger. But the mechanics of these nervous system changes have been unclear. Understanding the mechanics better could also have clinical applications: If scientists and doctors were to better understand how the nervous system changes during resistance training, they might be better able to help people who lose strength or muscular control after a stroke, for example, or as a result of aging or for other reasons. © 2020 The New York Times Company

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 27350 - Posted: 07.08.2020

By Jane E. Brody “Use it or lose it.” I’m sure you’re familiar with this advice. And I hope you’ve been following it. I certainly thought I was. I usually do two physical activities a day, alternating among walking, cycling and swimming. I do floor exercises for my back daily, walk up and down many stairs and tackle myriad physical tasks in and around my home. My young friends at the Y say I’m in great shape, and I suppose I am compared to most 77-year-old women in America today. But I’ve noticed in recent years that I’m not as strong as I used to be. Loads I once carried rather easily are now difficult, and some are impossible. Thanks to an admonition from a savvy physical therapist, Marilyn Moffat, a professor at New York University, I now know why. I, like many people past 50, have a condition called sarcopenia — a decline in skeletal muscle with age. It begins as early as age 40 and, without intervention, gets increasingly worse, with as much as half of muscle mass lost by age 70. (If you’re wondering, it’s replaced by fat and fibrous tissue, making muscles resemble a well-marbled steak.) “Sarcopenia can be considered for muscle what osteoporosis is to bone,” Dr. John E. Morley, geriatrician at Saint Louis University School of Medicine, wrote in the journal Family Practice. He pointed out that up to 13 percent of people in their 60s and as many as half of those in their 80s have sarcopenia. As Dr. Jeremy D. Walston, geriatrician at Johns Hopkins University School of Medicine, put it, “Sarcopenia is one of the most important causes of functional decline and loss of independence in older adults.” Yet few practicing physicians alert their older patients to this condition and tell them how to slow or reverse what is otherwise an inevitable decline that can seriously impair their physical and emotional well-being and ability to carry out the tasks of daily life. Sarcopenia is also associated with a number of chronic diseases, increasingly worse insulin resistance, fatigue, falls and, alas, death. © 2018 The New York Times Company

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: Development of the Brain
Link ID: 25415 - Posted: 09.05.2018

By Catherine Offord An experimental gene therapy for Duchenne Muscular Dystrophy has showed better-than-expected results in a three-patient trial, according to preliminary data presented by Cambridge, Massachusetts–based biotech Sarepta Therapeutics on Tuesday (June 19). Company shares jumped 60 percent following the news that the treatment dramatically boosted levels of microdystrophin, a muscle-protecting protein designed by researchers, and reduced levels of an enzyme associated with the disease. “I have spent my life wanting to make a real change in this disease,” principal investigator Jerry Mendell of Nationwide Children’s Hospital in Columbus tells STAT News. “Finally, we may be there. I am very hopeful. This is an emotional time for people in the field.” Duchenne Muscular Dystrophy (DMD) is a rare genetic disorder caused by loss-of-function mutations in the dystrophin gene. An X-linked condition, the disease mostly affects boys, and usually manifests itself in the form of muscle weakness in children between the ages of 3 and 5. There is no cure for DMD, and although steroids can slow the progression of symptoms, the disease eventually causes life-threatening damage to the heart muscles. Few patients live beyond their 30s. The US Food and Drug Administration (FDA) approved the first drug for DMD, Sarepta’s oligonucleotide therapeutic Exondys 51 (eteplirsen), in 2016. But the therapy was only effective in around 15 percent of DMD patients—those with a specific genetic mutation—and produced just marginal improvements in dystrophin levels. More-recent, preclinical approaches are experimenting with CRISPR to correct DMD-causing point mutations. © 1986-2018 The Scientist

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: Development of the Brain
Link ID: 25125 - Posted: 06.22.2018

By Diana Kwon Using CRISPR, researchers have successfully treated congenital muscular dystrophy type 1A (MDC1A), a rare disease that can lead to severe muscle wasting and paralysis, in mice. The team was able to restore muscle function by correcting a splicing site mutation that causes the disorder, according to a study published today (July 17) in Nature Medicine. “Instead of inserting the corrected piece of information, we used CRISPR to cut DNA in two strategic places,” study coauthor Dwi Kemaladewi, a research fellow at the Hospital for Sick Children (Sick Kids) in Toronto, explains in a statement. “This tricked the two ends of the gene to come back together and create a normal splice site.” By targeting both the skeletal muscles and peripheral nerves, the team was able to improve the animals’ motor function and mobility. “This is important because the development of therapeutic strategies for muscular dystrophies have largely focused on improving the muscle conditions,” Kemaladewi says in the release. “Experts know the peripheral nerves are important, but the skeletal muscles have been perceived as the main culprit in MDC1A and have traditionally been the focus of treatment options.” “The robustness of the correction we see in animal models to me is very encouraging,” Amy Wagers, a biologist at Harvard University who was not involved in this study, tells the Toronto Star. © 1986-2017 The Scientist

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23851 - Posted: 07.19.2017

By Michael Price Contrary to popular lore that portrays chimpanzees as having “super strength,” studies have only found modest differences with humans. But our closest relatives are slightly stronger by several measures, and now a study comparing the muscle fibers of different primates reveals a potential explanation: Humans may have traded strength for endurance, allowing us to travel farther for food. To determine why chimpanzees are stronger than humans—at least on a pound-for-pound basis—Matthew O’Neill, an anatomy and evolution researcher at the University of Arizona College of Medicine in Phoenix, and colleagues biopsied the thigh and calf muscles of three chimps housed at the State University of New York at Stony Brook. They dissected the samples into individual fibers and stimulated them to figure out how much force they could generate. Comparing their measurements to known data from humans, the team found that, at the individual fiber level, muscle output was about the same. Given that different fibers throughout the muscle might make a difference, the researchers conducted a more thorough analysis of tissue samples from pelvic and hind limb muscles of three chimpanzee cadavers from various zoos and research institutes around the United States. Previous studies in mammals have found that muscle composition between trunk, forelimb, and hind limb muscles is largely the same, O’Neill says, so he’s confident the samples are representative across most of the chimp’s musculature. The team used a technique called gel electrophoresis to break down the muscles into individual muscle fibers, and compared this breakdown to human muscle fiber data. © 2017 American Association for the Advancement of Science.

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23782 - Posted: 06.27.2017

By KATIE THOMAS Nolan and Jack Willis, twins from upstate New York, and just 10 other boys took part in a clinical trial that led to the approval last fall of the very first drug to treat their rare, deadly muscle disease. Now the Willis boys are again test cases as a different type of medical question comes to the fore: whether insurers will cover the controversial drug, Exondys 51, which can cost more than $1 million a year even though it’s still unclear if it works. The boys’ insurer, Excellus BlueCross BlueShield, refused to cover the cost of the drug because the twins, who are 15, can no longer walk. Their disease, Duchenne muscular dystrophy, overwhelmingly affects boys and causes muscles to deteriorate, killing many of them by the end of their 20s. “I’m cycling between rage and just sadness,” their mother, Alison Willis Hoke, said recently, on the day she learned that an appeal for coverage had been denied. For now, the company that sells the drug, Sarepta Therapeutics, is covering the treatment’s costs, but Mrs. Hoke does not know how long that will last. The desperation in Mrs. Hoke’s voice reflects a sobering reality for families of boys with the disease since their elation last fall over the drug’s approval. Because the Food and Drug Administration overruled its own experts — who weren’t convinced the Exondys 51 had shown sufficiently good results — and gave the drug conditional approval, many insurers are now declining to cover it or are imposing severe restrictions that render patients ineligible. The story of Exondys 51 raises complex and emotionally charged questions about what happens when the F.D.A. approves an expensive drug based on a lower bar of proof. In practice, health insurers have taken over as gatekeeper in determining who will get the drug. © 2017 The New York Times Company

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 23768 - Posted: 06.23.2017

Carrie Arnold Could a protein that originated in a virus explain why men are more muscular than women? Viruses are notorious for their ability to cause disease, but they also shape human biology in less obvious ways. Retroviruses, which insert their genetic material into our genomes to copy themselves, have left behind genes that help to steer our immune systems and mold the development of embryos and the placenta. Now researchers report in PLOS Genetics that syncytin, a viral protein that enables placenta formation, also helps to increase muscle mass in male mice1. These results could partially explain a lingering mystery in biology: why the males of many mammalian species tend to be more muscular than females. “As soon as I read it, my mind started racing with the potential implications,” says evolutionary virologist Aris Katzourakis of the University of Oxford, UK. About 8% of the 3 billion pairs of As, Ts, Gs and Cs that make up our DNA are viral detritus. Many of those viral hand-me-downs have degraded into useless junk — but not all, as a series of discoveries over the past 15 years has revealed. In 2000, scientists discovered that syncytin, a protein that enables the formation of the placenta, actually originated as a viral protein that humans subsequently ‘borrowed’2. That original viral protein enables the retrovirus to fuse with host cells, depositing its entire genome into the safe harbour of the cytoplasm. Syncytin has changed little from this ancestral protein form; it directs certain placental cells to fuse with cells in the mother’s uterus, forming the outer layer of the placenta. © 2016 Macmillan Publishers Limited

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 8: Hormones and Sex
Link ID: 22650 - Posted: 09.13.2016

Jon Hamilton Researchers have identified a substance in muscles that helps explain the connection between a fit body and a sharp mind. When muscles work, they release a protein that appears to generate new cells and connections in a part of the brain that is critical to memory, a team reports Thursday in the journal Cell Metabolism. The finding "provides another piece to the puzzle," says Henriette van Praag, an author of the study and an investigator in brain science at the National Institute on Aging. Previous research, she says, had revealed factors in the brain itself that responded to exercise. The discovery came after van Praag and a team of researchers decided to "cast a wide net" in searching for factors that could explain the well-known link between fitness and memory. They began by looking for substances produced by muscle cells in response to exercise. That search turned up cathepsin B, a protein best known for its association with cell death and some diseases. Experiments showed that blood levels of cathepsin B rose in mice that spent a lot of time on their exercise wheels. What's more, as levels of the protein rose, the mice did better on a memory test in which they had to swim to a platform hidden just beneath the surface of a small pool. The team also found evidence that, in mice, cathepsin B was causing the growth of new cells and connections in the hippocampus, an area of the brain that is central to memory. But the researchers needed to know whether the substance worked the same way in other species. So they tested monkeys, and found that exercise did, indeed, raise circulating levels of cathepsin in the blood. © 2016 npr

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 13: Memory and Learning
Link ID: 22353 - Posted: 06.24.2016

By ANDREW POLLACK In a confrontation between the hopes of desperate patients and clinical trial data, advisers to the Food and Drug Administration voted on Monday not to recommend approval of what would become the first drug for Duchenne muscular dystrophy. The negative votes came despite impassioned pleas from patients, parents and doctors who insisted that the drug, called eteplirsen, was prolonging the ability of boys with the disease to walk well beyond when they would normally be in wheelchairs. The problem was that the drug’s manufacturer, Sarepta Therapeutics, was trying to win approval based on a study involving only 12 patients without an adequate placebo control. The advisory panel voted 7 to 3, with three abstentions, that the clinical data did not meet the F.D.A. requirements for well controlled studies necessary for approval. However, some of the panel members had trouble reconciling the often compelling patient testimony with the F.D.A. legal requirements. “I was just basically torn between my mind and my heart,” said Richard P. Hoffmann, a pharmacist who was the consumer representative on the committee and who abstained. Dr. Bruce I. Ovbiagele, chairman of neurology at the Medical University of South Carolina, voted against approval but said, “Based on all I heard, the drug definitely works, but the question was framed differently.” On another question of whether the drug could qualify for so-called accelerated approval, a lower hurdle, the panel voted 7 to 6 against the drug. The F.D.A., which does not have to follow the advice of its advisory panels, is scheduled to decide whether to approve eteplirsen by May 26. © 2016 The New York Times Company

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 22142 - Posted: 04.26.2016

Tina Hesman Saey SAN DIEGO — Friendly ghosts help muscles heal after injury. Connective tissue sheaths that bundle muscle cells together leave behind hollow fibers when muscles are injured, Micah Webster of the Carnegie Institution for Science in Baltimore and colleagues discovered. Muscle-repairing stem cells build new tissue from inside those empty tunnels, known as ghost fibers, Webster reported December 13 at the annual meeting of the American Society for Cell Biology. Researchers previously knew that stem cells can heal muscle, but how stem cells integrate new cells into muscle fibers has been a mystery. Webster and colleagues used a special microscopy technique to watch stem cells in live mice as the cells fixed muscles damaged by snake venom. Stem cells from undamaged parts of the muscle fiber crawled back and forth through the ghostly part of the fibers and spaced themselves out evenly. Stem cells replicated themselves to reconstruct each muscle fiber inside its ghostly shell the researchers found. Stem cells didn’t move from one ghost fiber to another. The finding suggests that researchers will need to create artificial ghost fibers to repair injuries in which chunks of muscles are lost, such as in soldiers hit by explosives, Webster said. The researchers also reported the results online December 10 in Cell Stem Cell. M.T. Webster et al. Intravital imaging reveals ghost fibers as architectural units guiding muscle progenitors. Annual meeting of the American Society for Cell Biology, San Diego, December 13, 2015. M.T. Webster et al. Intravital imaging reveals ghost fibers as architectural units guiding myogenic progenitors during regeneration. Cell Stem Cell. Published online December 10, 2015. doi: 10.1016/j.stem.2015.11.005 © Society for Science & the Public 2000 - 2015

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 21704 - Posted: 12.16.2015

BY Tina Hesman Saey SAN DIEGO — A Golden retriever that inherited a genetic defect that causes muscular dystrophy doesn’t have the disease, giving scientists clues to new therapies for treating muscle-wasting diseases. The dog, Ringo, was bred to have a mutation that causes Duchenne muscular dystrophy in both animals and people. His weak littermates that inherited the same mutation could barely suckle at birth. But Ringo was healthy, with muscles that function normally. One of Ringo’s sons also has the mutation but doesn’t have the disease, said geneticist Natassia Vieira of Boston Children’s Hospital and Harvard University October 19 at the annual meeting of the American Society of Human Genetics. The dogs without the disease had a second genetic variant that caused their muscles to make more of a protein called Jagged 1, Vieira and her colleagues discovered. That protein allows muscles to repair themselves. Making more of Jagged 1 appears to compensate for the wasting effect of the muscular dystrophy mutation, although the researchers don’t yet know the exact mechanism. The finding suggests that researchers may one day be able to devise treatments for people with muscular dystrophies by boosting production of Jagged 1 or other muscle repair proteins. N. M. Vieira. The muscular dystrophies: Revealing the genetic and phenotypic variability. American Society of Human Genetics Annual Meeting, San Diego, October 19, 2014. © Society for Science & the Public 2000 - 2014

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 20226 - Posted: 10.22.2014

A drug to treat a particular form of Duchenne muscular dystrophy has been given the green light by the European Medicines Agency and could be available in the UK in six months. Translarna is only relevant to patients with a 'nonsense mutation', who make up 10-15% of those affected by Duchenne. The EMA decided not to pass the drug in January, but they have since re-examined the evidence. A campaign group said the drug must reach the right children without delay. There are currently no approved therapies available for this life-threatening condition. The patients who will benefit the most are those aged five years and over who are still able to walk, the EMA said. Duchenne muscular dystrophy is a genetic disease that gradually causes weakness and loss of muscle function. Patients with the condition lack normal dystrophin, a protein found in muscles, which helps to protect muscles from injury. In patients with the disease, the muscles become damaged and eventually stop working. There are 2,400 children in the UK living with muscular dystrophy, but only those whose condition is caused by a particular 'nonsense mutation' - namely 200 children - are suitable to use Translarna. The drug, ataluren, will be known by the brand name of Translarna in the EU. It was developed by PTC Therapeutics. The next step will see the European Commission rubberstamp the EMA's scientific 'green light' within the next three months and authorise the drug to be marketed in the European Union. At that point, individual member states, including the UK, must decide how it will be funded. The Muscular Dystrophy Campaign is calling for urgent meetings with National Institute of Health of Clinical Excellence (NICE) and NHS England to discuss how Translarna can be cleared for approval and use in the UK. It said families in the UK could have access to the drug by spring 2015. Robert Meadowcroft, chief executive of the campaign, said: "This decision by the EMA is fantastic news. BBC © 2014

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 19648 - Posted: 05.24.2014

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

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 18273 - Posted: 06.15.2013

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

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 18272 - Posted: 06.15.2013

Linda Carroll TODAY contributor Each day brings Jenn McNary another dose of hope and heartache as she watches one son get healthier while the other becomes sicker. Both of McNary's sons were born with Duchene muscular dystrophy. Max, 11, is receiving an experimental therapy that appears to be making him better, while 14-year-old Austin is slowly dying. Austin was too sick to be included in the clinical trials for a promising new drug called Eteplirsen. “He can’t get into a chair, out of his wheelchair, into his bed and onto the toilet,” McNary told NBC’s Janet Shamlian. Max, however, was exactly what researchers were looking for. He was put on Eteplirsen, and now he's back to running around, climbing stairs and even playing soccer. “It’s a miracle,” McNary said. “It really is a miracle drug. This is something that nobody ever expected and he looks like an almost normal 11-year-old.” Eteplirsen is designed to partially repair one of the common genetic mutations that causes DMD. Even a partial repair may enough to improve life for boys struck by the condition, which results from a defect in the dystrophin gene. That gene resides on the X chromosome, which is why only boys end up with DMD. Boys get one X and one Y chromosome. Girls get two copies of the X chromosome — one from their mother and one from their father — so even if they inherit a defective copy from their mom, they get a healthy one from their dad. Although they won’t suffer symptoms, girls wind up with a 50 percent chance of being carriers for DMD.

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 4: Development of the Brain
Link ID: 18196 - Posted: 05.28.2013

National Institutes of Health researchers used the popular anti-wrinkle agent Botox to discover a new and important role for a group of molecules that nerve cells use to quickly send messages. This novel role for the molecules, called SNARES, may be a missing piece that scientists have been searching for to fully understand how brain cells communicate under normal and disease conditions. "The results were very surprising,” said Ling-Gang Wu, Ph.D., a scientist at NIH’s National Institute of Neurological Disorders and Stroke. “Like many scientists we thought SNAREs were only involved in fusion." Every day almost 100 billion nerve cells throughout the body send thousands of messages through nearly 100 trillion communication points called synapses. Cell-to-cell communication at synapses controls thoughts, movements, and senses and could provide therapeutic targets for a number of neurological disorders, including epilepsy. Nerve cells use chemicals, called neurotransmitters, to rapidly send messages at synapses. Like pellets inside shotgun shells, neurotransmitters are stored inside spherical membranes, called synaptic vesicles. Messages are sent when a carrier shell fuses with the nerve cell’s own shell, called the plasma membrane, and releases the neurotransmitter “pellets” into the synapse. SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) are three proteins known to be critical for fusion between carrier shells and nerve cell membranes during neurotransmitter release.

Related chapters from BN: Chapter 11: Motor Control and Plasticity; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 18115 - Posted: 05.04.2013

By James Gallagher Health reporter, BBC News A 'molecular scalpel' shows promise in patients with a deadly muscle wasting condition, according to researchers. The gene for the protein dystrophin is damaged in people with Duchenne muscular dystrophy. A drug trial on 19 children, published in the Lancet, used the 'scalpel' to removed the damage and restore dystrophin production. The charity Muscular Dystrophy Campaign said there was "real hope for the future". Duchenne muscular dystrophy affects one in every 3,500 newborn boys. Throughout life the muscle wastes away and children can need a wheelchair by the age of 10. The condition can become life-threatening before the age of 30, when it affects the muscles needed to breathe and pump blood around the body. New approach The instructions for making a protein are in the genetic code, but this can be disrupted by mutations or deletions in the code. Stem cell and gene therapy research has tried to find ways of introducing a functional dystrophin gene. This study tried to do the best it could with the damaged code. BBC © 2011

Related chapters from BN: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 15590 - Posted: 07.25.2011