Light activity every day keeps disability at bay

http://feeds.feedburner.com/~r/sciencedaily/living_well/~4/-TqIU2dMtXQ

Pushing a shopping cart or a vacuum doesn’t take a lot of effort, but enough of this sort of light physical activity every day can help people with or at risk of knee arthritis avoid developing disabilities as they age, according to a new Northwestern Medicine study.It is known that the more time people spend in moderate or vigorous activities, the less likely they are to develop disability, but this is the first study to show that spending more time in light activities can help prevent disability, too.”Our findings provide encouragement for adults who may not be candidates to increase physical activity intensity due to health limitations,” said Dorothy Dunlop, professor of medicine at Northwestern University Feinberg School of Medicine and lead author of the study. “Even among those who did almost no moderate activity, the more light activity they did, the less likely they were to develop disability.”Results of the study were published April 29 in the British Medical Journal.The scientists identified a group of almost 1,700 adults, ages 45 to 79, from the Osteoarthritis Initiative study who were free of disability but were at elevated risk for developing it because they had knee osteoarthritis or other risk factors for knee osteoarthritis, such as obesity.Knee osteoarthritis commonly leads to disability, preventing people from engaging in activities essential to independent living and quality of life, such as dressing, bathing, walking across a room or making telephone calls, managing money and grocery shopping. Two-thirds of obese adults are expected to develop knee osteoarthritis during their lifetime.To track the amount and intensity of physical activity these at-risk people engaged in every day, scientists had them wear an accelerometer during waking hours for about a week. The device is worn around the hip and measures the intensity of movement. The data collected reveals how much time is spent in vigorous, moderate or light activities.Two years after collecting the results from the accelerometer, participants were surveyed and asked about the development of disabilities. As expected, more time spent in moderate or vigorous activity was associated with lower reports of disabilities, but researchers were pleased to find that greater time spent in light intensity activities also was related to fewer disabilities, even after accounting for time spent in moderate activities.Those who spent more than four hours per day doing light physical activity had more than a 30 percent reduction in the risk for developing disability compared to those spending only three hours a day in light activity (the least average number of hours collected in the study).The findings controlled for time spent in moderate or vigorous physical activity and other predictors of disability, both demographic and health factors.”We were delighted to see that more time spent during the day, simply moving your body, even at a light intensity, may reduce disability,” Dunlop said. “Now people with health problems or physical limitations, who cannot increase the intensity of their activity, have a starting place in the effort to stay independent.”Story Source:The above story is based on materials provided by Northwestern University. The original article was written by Erin White. Note: Materials may be edited for content and length.


Read More: Light activity every day keeps disability at bay

Brain, cognitive reserve protect long-term against cognitive decline, MS researchers find

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_health/~4/JuQGlCFN_qg

Multiple sclerosis researchers have found that brain reserve and cognitive reserve confer a long-term protective effect against cognitive decline.James Sumowski, PhD, lead author of the article, and John DeLuca, PhD, are at Kessler Foundation. Co-authors are from the Manhattan Memory Center, New York, NY, the San Raffaele Scientific Institute, Milan, Italy, and the University of Belgrade, Serbia. Neurology is the official journal of the American Academy of Neurology. Dr. Sumowski presented these findings at the AAN 2014 conference in Philadelphia.”Our research aims to answer these questions,” explained Dr. DeLuca. “Why do some people with MS experience disabling symptoms of cognitive decline, while others maintain their cognitive abilities despite neuroimaging evidence of significant disease progression? Can the theories of brain reserve and cognitive reserve explain this dichotomy? Can we identify predictors of cognitive decline?”In this study, memory, cognitive efficiency, vocabulary (a measure of intellectual enrichment/cognitive reserve), brain volume (a measure of brain reserve), and disease progression on MRI, were evaluated in 40 patients with MS at baseline and at 4.5-year followup. After controlling for disease progression, scientists looked at the impact of brain volume and intellectual enrichment on cognitive decline.Results supported the protective effects of brain reserve and cognitive reserve,” noted Dr. …


Read More: Brain, cognitive reserve protect long-term against cognitive decline, MS researchers find

Engineers grow functional human cartilage in lab

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_health/~4/F75jmglIVBM

Researchers at Columbia Engineering announced today that they have successfully grown fully functional human cartilage in vitro from human stem cells derived from bone marrow tissue. Their study, which demonstrates new ways to better mimic the enormous complexity of tissue development, regeneration, and disease, is published in the April 28 Early Online edition of Proceedings of the National Academy of Sciences (PNAS).”We’ve been able — for the first time — to generate fully functional human cartilage from mesenchymal stem cells by mimicking in vitro the developmental process of mesenchymal condensation,” says Gordana Vunjak-Novakovic, who led the study and is the Mikati Foundation Professor of Biomedical Engineering at Columbia Engineering and professor of medical sciences. “This could have clinical impact, as this cartilage can be used to repair a cartilage defect, or in combination with bone in a composite graft grown in lab for more complex tissue reconstruction.”For more than 20 years, researchers have unofficially called cartilage the “official tissue of tissue engineering,” Vunjak-Novakovic observes. Many groups studied cartilage as an apparently simple tissue: one single cell type, no blood vessels or nerves, a tissue built for bearing loads while protecting bone ends in the joints. While there has been great success in engineering pieces of cartilage using young animal cells, no one has, until now, been able to reproduce these results using adult human stem cells from bone marrow or fat, the most practical stem cell source. Vunjak-Novakovic’s team succeeded in growing cartilage with physiologic architecture and strength by radically changing the tissue-engineering approach.The general approach to cartilage tissue engineering has been to place cells into a hydrogel and culture them in the presence of nutrients and growth factors and sometimes also mechanical loading. But using this technique with adult human stem cells has invariably produced mechanically weak cartilage. So Vunjak-Novakovic and her team, who have had a longstanding interest in skeletal tissue engineering, wondered if a method resembling the normal development of the skeleton could lead to a higher quality of cartilage.Sarindr Bhumiratana, postdoctoral fellow in Vunjak-Novakovic’s Laboratory for Stem Cells and Tissue Engineering, came up with a new approach: inducing the mesenchymal stem cells to undergo a condensation stage as they do in the body before starting to make cartilage. He discovered that this simple but major departure from how things were usually? being done resulted in a quality of human cartilage not seen before.Gerard Ateshian, Andrew Walz Professor of Mechanical Engineering, professor of biomedical engineering, and chair of the Department of Mechanical Engineering, and his PhD student, Sevan Oungoulian, helped perform measurements showing that the lubricative property and compressive strength — the two important functional properties — of the tissue-engineered cartilage approached those of native cartilage. …


Read More: Engineers grow functional human cartilage in lab

MRI-guided biopsy for brain cancer improves diagnosis

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_health/~4/AzSBIu6lReQ

Neurosurgeons at UC San Diego Heath System have, for the first time, combined real-time magnetic resonance imaging (MRI) technology with novel non-invasive cellular mapping techniques to develop a new biopsy approach that increases the accuracy of diagnosis for patients with brain cancer.”There are many different types of brain cancer. Making an accurate diagnosis is paramount because the diagnosis dictates the subsequent course of treatment,” said Clark C. Chen, MD, PhD, vice-chairman of research, division of neurosurgery, UC San Diego School of Medicine. “For instance, the treatment of glioblastoma is fundamentally different than the treatment for oligodendroglioma, another type of brain tumor.”Chen said that as many as one third of brain tumor biopsies performed in the traditional manner can result in misdiagnosis. He cited two challenges with conventional biopsy.”First, because distinct areas of brain tumors exhibit different cell densities and higher cell densities are generally associated with higher tumor grade, biopsies taken from one region may yield a different diagnosis than if another area is biopsied,” said Chen. “Second, because tumors are hidden within the brain, surgeons must use mathematical algorithms to target where the biopsy should occur. As with all calculations, the process is subject to errors that the surgeon cannot easily correct in real time once the biopsy has begun.”Chen’s team applied an MRI technique called Restriction Spectrum Imaging (RSI) to visualize the parts of the brain tumor that contain different cell densities.”RSI allows us to identify the regions of the cell that are most representative of the entire tumor,” said Chen. “By targeting biopsies to these areas, we minimize the number of biopsies needed but still achieve a sampling that best characterizes the entire tumor.”To ensure a targeted biopsy, Chen performs the procedure in the MRI suite while the patient is under general anesthesia. Because conventional biopsy equipment cannot be used in the MRI, Chen uses a special MRI-compatible system called ClearPoint. This system utilizes an integrated set of hardware, software, and surgical equipment to allow the surgeon to target and visualize the path of the biopsy as well as the actual biopsy site, intraoperatively.”Surgeons have been performing brain biopsies in a near blind manner for the past fifty years. …


Read More: MRI-guided biopsy for brain cancer improves diagnosis

Increased prevalence of GI symptoms among children with autism, study confirms

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_health/~4/6lzeiIgEDoo

A new study conducted by researchers at Marcus Autism Center, Children’s Healthcare of Atlanta and Emory University School of Medicine indicates that children with autism spectrum disorder (ASD) are more than four times more likely to experience general gastrointestinal (GI) complaints compared with peers, are more than three times as prone to experience constipation and diarrhea than peers, and complain twice as much about abdominal pain compared to peers.The results are reported in the April 28, 2014, online early edition of the journal Pediatrics.While parents frequently express concern regarding GI symptoms among children with ASD in pediatric settings, this study is the first meta-analysis of all published, peer-reviewed research relating to this topic.”Our findings corroborate a history of anecdotal reports and case studies suggesting increased risk of GI concerns in autism,” says co-author William Sharp, PhD, director of the Pediatric Feeding Disorders Program at Marcus Autism Center and assistant professor of pediatrics at Emory University School of Medicine. “This analysis reinforces the need for greater clinical and research scrutiny in this area to guide best standards of care and to address important questions regarding the detection and treatment of GI symptoms among children with autism.”The process of detecting and studying possible GI concerns in children with ASD is complicated by the unique combination of behavioral, neurological and medical issues associated with the condition. Most notably, limitations in verbal communication in patients with ASD make it difficult for them to communicate information about GI symptoms, making it more challenging for physicians to detect possible underlying GI issues. In such cases, parents and medical professionals must rely on non-verbal signs that fall outside of the routine GI diagnostic evaluation.”In many cases, the only indication of a possible GI problem in autism may be the emergence or escalation of problem behaviors, such as self-injury, aggression, or irritability, that cannot be otherwise explained,” says co-author Barbara McElhanon, MD, pediatric gastroenterologist at Children’s Healthcare of Atlanta and assistant professor of pediatrics at Emory University School of Medicine. “Relying on these atypical signs to detect possible GI concerns can be difficult for practitioners because repetitive and stereotyped patterns of behavior occur so frequently in ASD and no guidelines exist to help parents and clinicians navigate the diagnostic process.”For this reason, McElhanon and her colleagues emphasize the need to develop a standardized screening instrument as well as clinical guidelines for conducting GI examinations among children with ASD, particularly non-verbal children. More detailed, standardized screening procedures would enhance detection, while also increasing awareness in the ASD community regarding what to look for among children suspected of possible GI disorders.”The important point from this research is that children with autism — who have difficulties in communicating their symptoms — need special attention from physicians to determine whether or not a child is experiencing GI distress” says Sharp. “Unfortunately for parents, the unfounded assertion that vaccinations somehow caused an inflammatory GI disease which then caused autism has significantly hindered progress in this field for years. Many studies have now shown no evidence of an association with vaccines, and vaccines are important for child health. That controversy diverted attention from the GI needs of children with ASD, and we hope that our work helps spur renewed investment for addressing these needs.”In addition to more standardized assessment, the authors recommend studying GI symptoms in ASD with consideration to the high rates of feeding problems and related dietary issues, such as food selectivity, in this population. “If food intake becomes highly restricted, a child is likely to experience issues like GI distress and constipation or diarrhea; but for children with autism, they often can’t communicate those issues in the same way,” says McElhanon. …


Read More: Increased prevalence of GI symptoms among children with autism, study confirms

Psychologists discover babies recognize real-life objects from pictures as early as nine months

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_health/~4/hCedpsqY9R0

Babies begin to learn about the connection between pictures and real objects by the time they are nine-months-old, according to a new study by scientists at Royal Holloway, University of London, and the University of South Carolina.The research, published today in Child Development, found that babies can learn about a toy from a photograph of it well before their first birthday.”The study should interest any parent or caregiver who has ever read a picture book with an infant,” said Dr Jeanne Shinskey, from the Department of Psychology at Royal Holloway. “For parents and educators, these findings suggest that, well before their first birthdays and their first words, babies are capable of learning about the real world indirectly from picture books, at least those that have very realistic images like photographs.”Researchers familiarized 30 eight and nine-month-olds with a life-sized photo of a toy for about a minute. The babies were then placed before the toy in the picture and a different toy and researchers watched to see which one the babies reached for first.In one condition, the researchers tested infants’ simple object recognition for the target toy by keeping both objects visible, drawing infants’ attention to the toys and then placing the toys inside clear containers. In another condition, they tested infants’ ability to create a continued mental idea of the target toy by hiding both toys from view, drawing infants’ attention to the toys and then placing the toys inside opaque containers.When the toys were visible in clear containers, babies reached for the one that had not been in the picture, suggesting that they recognized the pictured toy and found it less interesting than the new toy because its novelty had worn off. But when the toys were hidden in opaque containers, babies showed the opposite preference — they reached more often for the one that had been in the photo, suggesting that they had formed a continued mental idea of it.Dr Shinskey said: “These findings show that one brief exposure to a picture of a toy affects infants’ actions with the real toy by the time they reach nine-months-old. It also demonstrates that experience with a picture of something can strengthen babies’ ideas of an object so they can maintain it after the object disappears — so out of sight is not out of mind.”The study, which was carried out at the Baby Lab at Royal Holloway’s campus, in Egham, Surrey, was published online today in Child Development, the journal of the Society for Research in Child Development.Story Source:The above story is based on materials provided by University of Royal Holloway London. Note: Materials may be edited for content and length.


Read More: Psychologists discover babies recognize real-life objects from pictures as early as nine months

Wetlands likely to blame for atmospheric methane increases: Study

http://feeds.feedburner.com/~r/sciencedaily/earth_climate/ecology/~4/zpMs2QK06kE

A surprising recent rise in atmospheric methane likely stems from wetland emissions, suggesting that much more of the potent greenhouse gas will be pumped into the atmosphere as northern wetlands continue to thaw and tropical ones to warm, according to a new international study led by a University of Guelph researcher.The study supports calls for improved monitoring of wetlands and human changes to those ecosystems — a timely topic as the Intergovernmental Panel on Climate Change prepares to examine land use impacts on greenhouse gas emissions, says Prof. Merritt Turetsky, Department of Integrative Biology.Turetsky is the lead author of a paper published today in Global Change Biology based on one of the largest-ever analyses of global methane emissions. The team looked at almost 20,000 field data measurements collected from 70 sites across arctic, temperate and tropical regions.Agnieszka Kotowska, a former master’s student, and David Olefeldt, a post-doc at Guelph, also were among 19 study co-authors from Canada, the United States, the United Kingdom, Finland, Germany and Sweden.One of the strongest greenhouse gases, methane comes from agriculture and fossil fuel use, as well as natural sources such as microbes in saturated wetland soils.The amount of atmospheric methane has remained relatively stable for about a decade, but concentrations began to rise again in 2007. Scientists believe this increase stems partly from more methane being released from thawing northern wetlands.Scientists have assumed that wetland methane release is largest in the tropics, said Turetsky.”But our analyses show that northern fens, such as those created when permafrost thaws, can have emissions comparable to warm sites in the tropics, despite their cold temperatures. That’s very important when it comes to scaling methane release at a global scale.”The study calls for better methods of detecting different types of wetlands and methane release rates between flooded and drained areas.Fens are the most common type of wetland in Canada, but we lack basic scientific approaches for mapping fens using remote sensing products, she said.”Not only are fens one of the strongest sources of wetland greenhouse gases, but we also know that Canadian forests and tundra underlain by permafrost are thawing and creating these kinds of high methane-producing ecosystems.”Most methane studies focus on measurements at a single site, said co-author Narasinha Shurpali, University of Eastern Finland. “Our synthesis of data from a large number of observation points across the globe is unique and serves an important need.”The team showed that small temperature changes can release much more methane from wetland soils to the atmosphere. But whether climate change will ramp up methane emissions will depend on soil moisture, said Turetsky.Under warmer and wetter conditions, much more of the gas will be emitted. If wetland soils dry out from evaporation or human drainage, emissions will fall — but not without other problems.In earlier studies, Turetsky found drying peatlands can spark more wildfires.Another study co-author, Kim Wickland, United States Geological Survey, said, “This study provides important data for better accounting of how methane emissions change after wetland drainage and flooding.”Methane emissions vary between natural and disturbed or managed wetlands, says Wickland, who has helped the IPCC improve methods for calculating greenhouse gas emissions from managed wetlands.Turetsky holds a Canada Research Chair in Integrative Ecology. She and her students examine how ecosystems regulate climate in field sites in Canada and Alaska.Story Source:The above story is based on materials provided by University of Guelph. Note: Materials may be edited for content and length.


Read More: Wetlands likely to blame for atmospheric methane increases: Study