Links for Keyword: Regeneration

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


Links 81 - 100 of 156

Paralysed patients are looking to scientists working on spinal-cord regeneration to help them walk again. HELEN PEARSON It was a miracle of almost biblical proportions. In 1998, scientists in Israel revealed that rats whose spinal cords had been severed had walked again after an injection of healing immune cells called macrophages1. Their hopes buoyed by enthusiastic media coverage, paralysed patients began to dream of taking their own tentative steps. Five years on, the status of those dreams remains unclear. Proneuron Biotechnologies, a Los Angeles-based company founded on the back of the research of lead investigator Michal Schwartz at the Weizmann Institute of Science in Rehovot, is expected soon to release the results of an initial trial of the procedure on eight patients with spinal injuries. Media reports have indicated that some patients have recovered some feeling and movement, but many researchers do not expect a repeat of the rodent miracle. Indeed, they claim that at least one group has since tried, and failed, to reproduce Schwartz's original animal results. Schwartz's study is not alone in this regard. Over the past few years, scientists working on spinal-cord repair have revealed encouraging results on several occasions, only to find that other groups have struggled to recreate the same outcome. Three papers published in Neuron2-4 last month underline the point, reporting contradictory findings in parallel studies of 'knockout' mice lacking proteins that are believed to be among the main inhibitors of nerve growth in the spinal cord. "Reproducibility has been a major problem in spinal-cord injury," says Oswald Steward, director of the Reeve-Irvine Research Center at the University of California, Irvine. © Nature News Service / Macmillan Magazines Ltd 2003

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 3878 - Posted: 06.24.2010

Molecules behind left-right generator might help spinal cord treatments. HELEN PEARSON Thanks to a mouse that jumps like a kangaroo, researchers have discovered two molecules that drive the ability to walk. They hope that similar results might eventually help people to recover from spinal-cord injuries. Many animals' spinal cords house a circuit called the central pattern generator (CPG), which triggers legs to perform a left-right gait. Some therapies for partially paralysed patients attempt to stimulate the CPG by supporting them over a treadmill and sending electrical pulses to the spine. But exactly which nerves are involved, and how they work, has been unclear. For Klas Kullander, of Gothenburg University in Sweden, and his colleagues, the clue came from mice genetically engineered to lack two molecules called ephrinB3 and EphA4. © Nature News Service / Macmillan Magazines Ltd 2003

Related chapters from BP7e: 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 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 3594 - Posted: 06.24.2010

Can bone marrow seed the brain with fresh neurons? BY EMILY SOHN The healing promise of stem cells is one of medicine's bright hopes. But the field needs some healing itself. It is beset by controversy because stem cells able to develop into every kind of tissue come from discarded embryos. What if adults had their own reserves of universal cells? Now comes the latest hint that they do: evidence that stem cells from adult bone marrow can turn into brain cells. If it holds up, the finding might lead to new techniques for treating brain injury and diseases like Alzheimer's, without the ethical baggage of embryo cells. But the study has also inflamed a debate over what adult stem cells can and cannot do. In test tubes, mice, and even some human studies, bone marrow stem cells have seemed to turn into tissues including liver, heart, skin, and lung, although other groups have often failed to replicate the findings. Two years ago, researchers also showed that in mice, marrow stem cells could become brain cells. Copyright © 2003 U.S. News & World Report

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 3386 - Posted: 06.24.2010

Seven years after actor Christopher Reeve was paralyzed from a spinal cord injury, tests show his brain has maintained a near-normal ability to detect feeling and direct movement. The finding suggests the "use it or lose it" rule may not apply to the brain after all, experts say. By Brian Branch-Price, AP Years of research has shown in animals that when the spinal cord is severed, cutting off signals to parts of the brain, then the brain will reorganize itself and eventually not respond to signals from the paralyzed part of the body. But a study by researchers at Washington University School of Medicine in St. Louis using a MRI technique shows that may not be true for Reeve. "We see evidence of some reorganization in this patient," said Dr. Maurizio Corbetta, a Washington University neurology researcher. "But we also see strong evidence for stability ... which goes against the principle of 'use it or lose it.'" Copyright 2002 The Associated Press. © Copyright 2002 USA TODAY

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 15: Language and Our Divided Brain
Link ID: 3143 - Posted: 06.24.2010

Beam could help repair spine damage or wire up implants. PHILIP BALL A laser beam can guide nerve cells to grow in a particular direction, researchers have shown. The technique might help damaged nerves to regrow or could connect them to electronic implants, such as artificial retinas and prosthetic limbs. Rat and mouse nerve cells growing over a glass plate take the path pointed out by a red laser, report Allen Ehrlicher, of the University of Leipzig in Germany, and colleagues1. The cells move towards the spot of laser light, travelling as if down a gentle slope, they think. Moreover, the laser does not harm the cells, the researchers report, even if it leads them along a zigzag. Normally, cells don't like making sharp turns; forced to do so, they soon try to straighten out. Previous attempts to guide cells in channels or on adhesive tracks damaged their delicate walls. © Nature News Service / Macmillan Magazines Ltd 2002

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 3085 - Posted: 06.24.2010

Topic Editor: John F. Alksne, M.D Table of Contents 1. The role of cell therapy for stroke. Douglas Kondziolka, Lawrence Wechsler, Elizabeth Tyler-Kabara, and Cristian Achim 2. Role of cell therapy in Parkinson disease. Olle Lindvall and Peter Hagell 3. Status of fetal tissue transplantation for the treatment of advanced Parkinson disease. Paul E. Greene and Stanley Fahn 4. Glial cell line-derived neurotrophic factor-supplemented hibernation of fetal ventral mesencephalic neurons for transplantation in Parkinson disease: long-term storage. Adam O. Hebb, Kari Hebb, Arun C. Ramachandran, and Ivar Mendez 5. Growth factor gene therapy for Alzheimer disease. Mark H. Tuszynski, Hoi Sang U, John Alksne, Roy A. Bakay, Mary Margaret Pay, David Merrill, and Leon J. Thal Copyright© 1998-2002; American Association of Neurological Surgeons

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 15: Language and Our Divided Brain
Link ID: 3011 - Posted: 06.24.2010

Protein cocktail persuades stem-cell grafts to become neurons. MICHAEL STEBBINS A simple protein shake coaxes human neural stem cells from fetuses to develop into proper neurons when implanted into live animals' brain or spinal cord. The technique jumps an important hurdle on the path to stem-cell therapies. To fix neurodegenerative diseases and repair spinal-cord injuries, new neurons must grow in the place of the damaged ones. Unfortunately, most engrafted neural stem cells either don't develop, or turn into support cells rather than neurons, even though they have the potential to grow into any type of cell. "We used proteins involved in the development of neurons to point them in the right direction before they are engrafted," says team member Ping Wu of the University of Texas Medical Branch in Galveston. "So what is happening to the cells is natural for them." © Nature News Service / Macmillan Magazines Ltd 2002

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 5: The Sensorimotor System
Link ID: 2979 - Posted: 06.24.2010

Like the beams in a house infested with termites, certain neurons in people with Parkinson's disease slowly disintegrate, causing muscle tremors and stiffness. Now, researchers have repaired such degenerating neurons in mice using stem cells. The results could eventually lead to better treatments for humans. People with Parkinson's disease slowly lose a group of neurons that help coordinate body movement. These neurons reside in a brain region called the substantia nigra and use dopamine to communicate with each other. Neuroscientists had previously used neural stem cells to replace dead neurons in brains with other kinds of damage, so neurobiologist Evan Snyder of Harvard Medical School in Boston and colleagues reasoned that neural stem cells could replace the dopamine neurons in mice with a Parkinson's-like condition. Copyright © 2002 by the American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 2809 - Posted: 06.24.2010

Researchers receive grant to use robots to improve walking Irvine, Calif., Paralysis from spinal cord injury was significantly reversed by adding tiny nerves from the rib cage and mixing them with a powerful growth inducer found in most nerve cells, a UC Irvine and Long Beach Veterans Administration Medical Center study has found. The study, conducted in rats, suggests that nerve cells can be inserted and stimulated to grow through damaged areas of the spinal cord, perhaps leading to better treatments for spinal cord injury. The research is part of a wave of studies challenging the conventional wisdom that severed nerves in the spinal cord are nearly impossible to regenerate. The study appears in the October issue of the Journal of Neurotrauma. Dr. Vernon Lin, professor of physical medicine at UCI and director of the Spinal Cord Injury Group at the Long Beach V.A., and his colleagues found that grafting nerves from the rib cage and adding the growth stimulator, a molecule called aFGF, partially restored hind leg movement in rats that had their spinal cords severed. © Copyright 2002 UC Regents

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 5: The Sensorimotor System
Link ID: 2764 - Posted: 06.24.2010

Copyright © 2002 AP Online By ANDREW BRIDGES, AP Science Writer LOS ANGELES - An experimental nerve-graft surgery allowed a paraplegic woman whose spinal cord was severed in an automobile accident to reacquire limited use of her legs, an Italian doctor reported this week at a conference in California. In a 14-hour surgery performed in July 2000, Dr. Giorgio Brunelli, of the Universita' di Brescia, Italy, removed a portion of the 28-year-old's sciatic nerve and used it as a graft to connect the undamaged portion of her spine to muscles in her buttocks and thighs. He said the graft allowed the regrowth of nerves connected to the central nervous system into the muscle tissue. The unidentified patient first showed movement in her legs in September and since has begun walking with assistance, Brunelli said. The woman had used a wheelchair for five years prior to the surgery. Copyright © 2001 Nando Media

Related chapters from BP7e: 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 13: Memory, Learning, and Development
Link ID: 2561 - Posted: 06.24.2010

Exclusive from New Scientist Print Edition Two men paralysed on one side of their body can walk again, thanks to an ingenious implant that uses signals from a healthy leg to control a paralysed one. Both men, aged 47 and 64, had been paralysed by strokes. Previously neither could walk unaided. But after sensors were placed over certain muscle groups on the healthy leg and stimulators implanted in the paralysed leg, they can now walk, stand and sit. The unique therapy allows a patient to move their paralysed leg in a natural way without being aware that they are doing it, says Wenwei Yu, who developed the technique at Hokkaido University in Sapporo, Japan. But it could be another five years or more before the technology becomes available, he says. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: 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 13: Memory, Learning, and Development
Link ID: 2550 - Posted: 06.24.2010

Exclusive from New Scientist Print Edition Nerve cells extracted from a patient's own nose could one day be used to cure paralysis. At least, that is the hope of neuroscientists in Australia who have announced the beginning of tests on people. The team, led by Alan Mackay-Sim of Griffith University in Brisbane, has recruited three people who have been paralysed from the waist down for between six months and three years, and plans to enlist another five. Half the patients will receive a spinal injection of the nasal cells. The cells, called olfactory ensheathing cells, connect the lining of the nose with the brain, giving us our sense of smell. Unlike most nerve cells, they continue to regenerate throughout life, a property that probably evolved because they can be destroyed by infections. "There's only a few microns of mucus between the air and the nerve endings," points out Mackay-Sim. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 15: Language and Our Divided Brain; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 2303 - Posted: 06.24.2010

Copyright © 2002 United Press International BALTIMORE, - Scientists announced Wednesday they have figured out a new way to get nerve cells to regenerate in the laboratory and have come one step closer to being able to repair spinal cord injuries - although that prospect remains years away. "For the first time in history there is some optimism that we may be able to get functional recovery of spinal cord injuries," Ronald L. Schnaar, co-author of the study and professor of pharmacology and of neuroscience at Johns Hopkins University, told United Press International. "Whether it's this decade or next decade, I think we'll begin to see this knowledge turned into therapies." Schnaar and colleagues at the University of Hamburg, Germany, discovered how to modulate a molecular signal that inhibits the regeneration of nerve cells after they are damaged. Copyright © 2001 Nando Media

Related chapters from BP7e: 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 13: Memory, Learning, and Development
Link ID: 2251 - Posted: 06.24.2010

by Francesco Fiondella, BioMedNet News When nerves are severed by spinal cord injury, a tangle of long and branched molecules forms around them like "overgrown shrubbery," as one expert puts it, and prevents the damaged fibers from regenerating. Researchers now say that selectively pruning this molecular growth with chemicals results in "modest but significant" nerve regeneration in rat models, according to published and unpublished findings presented this week. A class of molecules known as chondroitin sulphate proteoglycans (CSPGs), a protein called Nogo, and another called myelin associated glycoprotein (MAG) are among the most studied of this molecular shrubbery shown to inhibit nerve regeneration. © Elsevier Science Limited 2002

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 15: Language and Our Divided Brain; Chapter 5: The Sensorimotor System
Link ID: 1930 - Posted: 06.24.2010

Bacterial enzyme chews through nerve growth barrier. HELEN PEARSON An enzyme that clears a path for growing nerves can help damaged spinal cord to repair itself, researchers have found. The enzyme could one day help to treat paralysing injuries, in conjunction with other therapies. Damaged nerves in the spinal cord do not normally recover. The surrounding cells multiply to form a dense scar, and secrete a thicket of barrier molecules that nerves cannot cross. Like a miniature lawnmower, the bacterial enzyme chondroitinase ABC trims back these obstructing molecules, Elizabeth Bradbury of King's College London and her team have shown1. Rats with damaged spinal cords injected with the enzyme partly recover from their injury. * Bradbury, E. J. Chondrotinase ABC promotes functional recovery after spinal cord injury. Nature, 416, 636, (2002). © Nature News Service / Macmillan Magazines Ltd 2002

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 1851 - Posted: 06.24.2010

Study in rats points to potential human therapy By Nicolle Charbonneau HealthScoutNews Reporter A study by British researchers reports that rats with partial spinal cord injuries regained neurological function and their ability to walk normally after treatment with the enzyme, known as chondroitinase ABC (ChABC). Their findings appear in tomorrow's issue of Nature. While previous research had shown this enzyme could make nerve fibers regenerate in the brain, co-author Dr. James W. Fawcett, a professor at the University of Cambridge's Centre for Brain Repair, says this study is the first demonstration of the enzyme's effect on the spinal cord. SOURCES: James W. Fawcett, M.D., Ph.D., professor, Department of Physiology, Centre for Brain Repair, University of Cambridge, Cambridge, England; Lars Olson, Ph.D., professor, Department of Neuroscience, Karolinska Institute, Stockholm, Sweden; April 11, 2002, Nature Copyright © 2002 ScoutNews, LLC. All rights reserved.

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 1844 - Posted: 06.24.2010

An injectable hydrogel could aid recovery from brain injury by helping stimulate tissue growth at the site of the wound, researchers say. Research on rats suggests the gel, made from synthetic and natural sources, may spur growth of stem cells in the brain. The gel has been developed by Dr Ning Zhang at Clemson University, South Carolina, who presented her work to a conference on military health research. She predicted the gel may be ready for human testing in about three years. Following a brain injury the tissues tend to swell up and this causes the loss of even more cells, compounding the damage caused by the original wound. The standard treatments attempt to minimise this secondary damage at the site of the injury, for instance by lowering the temperature or relieving the build up of pressure. However, their impact is often limited. Scientists believe that transplanting donor brain cells into the wound to repair tissue damage is potentially a more productive approach. But while this method has had some success in treating some central nervous system diseases, it has produced very limited results when used to treat brain injuries. The donor cells do not tend to thrive at the site of injury, or to stimulate repair. This could be due to inflammation and scarring at the injury site, and the lack of supportive tissue and blood supply to provide the necessary nutrients. Researchers say the advantage of the new gel, which is injected into the injury in liquid form, is that it can be loaded with different chemicals to stimulate various biological processes. (C)BBC

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 13237 - Posted: 09.03.2009

Doctors hope to use the body's own nerves to bridge the gap in the spinal cord left by paralysing injuries. Marie Filbin, from the City University of New York, took a nerve leaving the spine just above an injury, and reattached it below. New Scientist magazine reports that rats used in the experiment showed some signs of renewed movement. A UK expert said the injury location could govern whether a suitable nerve was available for surgery. An injury that breaks or severely damages the spinal cord can cause permanent disability, with the extent set by exactly how far down the spine the damage has happened. Scientists are hunting for ways to repair that damage, including using growth-promoting chemicals to encourage healing across the 'gap', and grafts of nerve fibres from elsewhere in the body. The New York approach is slightly different - it takes one of the nerves that naturally leaves the spinal column, disconnects it from its destination, then plugs it back into the spinal cord using a protein "glue". In the case of the rats, this was a nerve heading for the abdominal muscles, which was taken just above a break in the spinal cord, and reattached below. After just two weeks, it became clear that the new arrangement was working, with the nerve growing and starting to form connections with its new neighbour. Sending electrical impulses down the spinal cord caused twitching in the lower limbs, again indicating that connections had been made. There were no ill-effects in the abdominal muscle, as other nerves connected to it compensated for the loss of one connection. (C)BBC

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 11291 - Posted: 02.07.2008

Silk may be able to help repair damaged nerves, according to scientists. The UK researchers have shown how nerve cells can grow along bundles of a special fibre, which has properties similar to spider silk. They hope the silk will encourage cell re-growth across severed nerves, possibly even in damaged spinal cords. A picture of nerve cells growing on the silk is one of the winning images in this year's Wellcome Trust Biomedical Image Awards. It is one of 26 images - many revealing objects invisible to the naked eye - captured from medical research programmes across Britain. The silk, dubbed Spidrex, comes from silk worms that have been modified to give the fibres special properties that help cells to bind. Professor John Priestley, a neuroscientist from Queen Mary's School of Medicine and Dentistry, London, and lead researcher, said the silk acted as a scaffold on which nerve cells could grow. The team has tested the silk in tissue culture (shown in the winning image) and in animals - and in both cases, said Professor Priestly, the results had been good. (C)BBC

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 9135 - Posted: 07.13.2006

CINCINNATI--The number of sites in children's brains involved in language recognition decreases as the children age, according to a University of Cincinnati (UC) study. The finding, says Jerzy Szaflarski, MD, PhD, an assistant professor of neurology at the UC Academic Health Center, suggests that as a child grows more language proficient, recalling words may involve less effort. It also supports earlier explanations as to why young children who injure a large part of one side of the brain often recover completely, or almost completely. Funded by the National Institute of Child Health and Human Development, the study will be presented April 6 at the annual meeting of the American Academy of Neurology in San Diego. The paper will also appear in print in the April Annals of Neurology. "The decrease in activity sites may mean that language areas in the brain are more flexible when children are younger and become more specialized as they mature," Dr. Szaflarski says. "This raises hope for rehabilitation of brain function in children after stroke or traumatic brain injuries," he says.

Related chapters from BP7e: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory, Learning, and Development
Link ID: 8750 - Posted: 04.08.2006