Links for Keyword: Neuroimmunology
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Friends, not family, are the key to a longer life, a new study suggests. While previous research has found that strong social networks help older people live longer, the work had not distinguished between contact with friends or relatives. The new study followed almost 1500 Australians, initially aged over 70. Those who at the start reported regular close personal or phone contact with five or more friends were 22% less likely to die in the next decade than those who had reported fewer, more-distant friends. But the presence or absence of close ties with children or other relatives had no impact on survival. The reasons are not entirely clear. Friends and confidantes might help with coping in times of stress and difficulty, the team suggests. They might also encourage healthy behaviours, such as seeking help for new medical symptoms. Journal reference: Journal of Epidemiological and Community Health (vol 59, p 538) © Copyright Reed Business Information Ltd.
Rest assured, the cells that guard your brain are no slackers. New movies of brain cells called microglia reveal that these sentries constantly extend and retract tiny arms to probe the fluid spaces between brain cells for signs of injury or infection. The findings present a radically new view of how these cells protect the brain. Microglia are the immune system's foot soldiers in the brain. They spring into action when damage occurs, creating a protective barrier around the injury and cleaning up dead cells and other debris. What the microglia do between crises has been unclear, largely because getting the cells under a microscope has required excising a chunk of brain tissue--thereby causing damage that sends the cells into emergency response mode. The new study gets around that obstacle by using genetically engineered mice whose microglia produce a fluorescent green protein. The research team, led by Axel Nimmerjahn at the Max Planck Institute for Medical Research in Heidelberg, Germany, created a window on the brain of 12 such mice by shaving away a small patch of skull until only a transparent sliver of bone remained. Using a noninvasive technique called two-photon microscopy, the team snapped pictures of glowing microglia near the surface of the brain for several hours and compiled the images into time-lapse movies. Copyright © 2005 by the American Association for the Advancement of Science.
By Rob Stein, Washington Post Staff Writer According to the Bible, "a merry heart doeth good like a medicine." Now, modern science may be validating that Old Testament proverb -- a good laugh may actually help fend off heart attacks and strokes. "We believe laughing is good for your health," said Michael Miller of the University of Maryland School of Medicine in Baltimore, who led the research. "And we think we have evidence to show why that's the case." A growing body of other evidence has suggested that negative emotions, particularly depression and stress, can be harmful, making people more prone to illness, more likely to experience suffering from their ailments and less likely to recover as quickly, or at all. One recent study even found sudden emotional shock can trigger life-threatening heart symptoms that many doctors mistake for a classic heart attack. Miller himself, along with his colleagues, had done a study that found people who have a negative reaction to social situations tend to be more prone to heart disease. But far less has been done to examine whether positive emotions can reduce the risk and complications of illness. © 2005 The Washington Post Company
A BIG brain is a sign of a healthy immune system, at least as far as male birds are concerned. Anders Møller at Pierre and Marie Curie University in Paris, France, and colleagues examined data from 127 bird species. They found that in species with larger brains for their body size, such as yellowhammers and barn swallows, the males also tended to have a larger spleen and bursa of Fabricius - two organs central to the immune system. The pattern did not hold for organs like the heart and liver not involved the immune system, or for females (Journal of Evolutionary Biology, DOI: 10.1111/j.1420-9101.2004.00805.x). Møller says that females choosing brainy males, perhaps by favouring a large song repertoire, may also be selecting for males with better immune systems. Previous research has shown that infections impair a bird's cognitive abilities, so a male displaying his braininess may also be showing off good genes for seeing off parasites. What's more the pattern may exist in other animals. "I can't see any reason why it should be restricted to birds," Møller says. © Copyright Reed Business Information Ltd.
Related chapters from BP7e: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 11: Emotions, Aggression, and Stress
Link ID: 6668 - Posted: 06.24.2010
Fatigue is in the mind, not the muscles, suggests a new study. But it can still have a serious impact on athletic performance. The finding could lead to treatments for conditions like chronic fatigue syndrome, or the development of illicit performance-enhancing drugs. Traditionally, fatigue was viewed as the result of over-worked muscles ceasing to function properly. But evidence is mounting that our brains make us feel weary after exercise (New Scientist print edition, 20 March). The idea is that the brain steps in to prevent muscle damage. Now Paula Robson-Ansley and her colleagues at the University of Cape Town in South Africa have demonstrated that a ubiquitous body signalling molecule called interleukin-6 plays a key role in telling the brain when to slow us down. Blood levels of IL-6 are 60 to 100 times higher than normal following prolonged exercise, and injecting healthy people with IL-6 makes them feel tired. © Copyright Reed Business Information Ltd.
Bruce Bower The old saying that it's better to give than to receive may be true, at least when it comes to social support. Over a 5-year period, seniors who provided either a lot of practical assistance to friends, relatives, and neighbors or regular emotional support to their spouses displayed a higher survival rate than those who didn't provide such help, a new study finds. New data suggest that older people who provide social support to spouses, friends, and others live longer than other seniors do. In contrast, recipients of plentiful social support showed death rates similar to those of their peers who got little or no such support, say psychologist Stephanie L. Brown of the University of Michigan in Ann Arbor and her colleagues. Copyright ©2003 Science Service.
-- An increasing number of doctors and other health experts have been encouraging older adults to rise from their recliners and go for a walk, a bike ride, a swim, or engage in just about any other form of physical activity as a defense against the potentially harmful health consequences of a sedentary lifestyle. "Exercise is touted as a panacea for older adults," said Jeffrey Woods, a kinesiology professor at the University of Illinois at Urbana-Champaign, who noted that fitness programs are routinely recommended for people with various health problems -- from diabetes to heart disease. Health experts generally recognize that this population benefits from physical fitness, he said. What they don't know is why exercise appears to have certain preventive and restorative health effects. Also unknown is what -- if any -- relationship exists between exercise and immune functioning. Copyright © 1992-2003 Bio Online, Inc.
Researchers want to understand the control center of the activation process | By Josh P. Roberts We can do things that haven't been done before, I think, ever in cell biology," exclaims Mark Davis of Stanford University. His 3-D, fluorescence video-microscopy system allows him to count the number of antigen receptors being stimulated on a given T cell, and to follow that cell through time. Davis asks of the single cell, "What do you need in the way of signals to get synapses? And what is the sensitivity of a T cell to antigen?" The synapse Davis refers to is the immunological synapse, where T cells receive their marching orders; understanding it is vital to appreciating how an immune response is set in motion. "We like to think of the immunological synapse as the brain," says cell biologist Abraham (Avi) Kupfer. "It's like a control center of the activation process." SIMPLICITY ITSELF In its simplest incarnation, the immunological synapse (IS) consists of two pairs of molecules. Michael Dustin and colleagues at Washington University put freely diffusible MHC-peptide (major histocompatability complex class II plus bound peptide) with ICAM-1 (intracellular adhesion molecule-1) into an artificial lipid bilayer. By adding T cells, the researchers induced T-cell antigen receptor (TCR) and lymphocyte function-associated antigen-1 (LFA-1) to form "kind of a bull's-eye-like pattern," he recalls. ©2003, The Scientist Inc.
May Increase Susceptibility To Inflammatory Diseases Such As Allergic, Autoimmune Or Cardiovascular Diseases WASHINGTON - Chronic stress not only makes people more vulnerable to catching illnesses but can also impair their immune system's ability to respond to its own anti-inflammatory signals that are triggered by certain hormones, say researchers, possibly altering the course of an inflammatory disease. This finding is reported on in the November issue of Health Psychology, published by the American Psychological Association (APA). Chronic stress seems to impair the immune system's capacity to respond to glucocorticoid hormones that normally are responsible for terminating an inflammatory response following infection and/or injury, according to researchers Gregory E. Miller, Ph.D., of Washington University at St. Louis and colleagues. To examine what happens to people's immune systems during on-going stressful situations, the researchers compared 25 healthy parents with children undergoing treatment for pediatric cancer with 25 healthy parents with healthy children on measures of mental health, effects of social support and certain immune system responses. All the parents had blood drawn at the initial session and salivary cortisol samples taken at intermittent times over two days. © PsycNET 2002 American Psychological Association
By Julie Steenhuysen CHICAGO (Reuters) - Optimists live longer, healthier lives than pessimists, U.S. researchers said on Thursday in a study that may give pessimists one more reason to grumble. Researchers at University of Pittsburgh looked at rates of death and chronic health conditions among participants of the Women's Health Initiative study, which has followed more than 100,000 women ages 50 and over since 1994. Women who were optimistic -- those who expect good rather than bad things to happen -- were 14 percent less likely to die from any cause than pessimists and 30 percent less likely to die from heart disease after eight years of follow up in the study. Optimists also were also less likely to have high blood pressure, diabetes or smoke cigarettes. The team, led Dr. Hilary Tindle, also looked at women who were highly mistrustful of other people -- a group they called "cynically hostile" -- and compared them with women who were more trusting. Women in the cynically hostile group tended to agree with questions such as: "I've often had to take orders from someone who didn't know as much as I did" or "It's safest to trust nobody," Tindle said in a telephone interview. "These questions prove a general mistrust of people," said Tindle, who presented her study Thursday at the American Psychosomatic Society's annual meeting in Chicago.
The power of the mind has been overestimated when it comes to fighting cancer, US scientists say. They said they found that a patient's positive or negative emotional state had no direct bearing on cancer survival or disease progression. The University of Pennsylvania team followed more than 1,000 patients with head and neck cancer. But experts said the Cancer journal study should not deter people from adopting a "fighting spirit". Indeed, a positive outlook can help patients cope with gruelling cancer therapies and resume a "normal" life, a spokeswoman for Macmillan Cancer Support said. Seeking emotional support may be beneficial to cancer patients, said the researchers. Lead author Dr James Coyne said: "If cancer patients want psychotherapy or to be in a support group, they should be given the opportunity. There can be lots of emotional and social benefits. But they should not seek such experiences solely on the expectation that they are extending their lives. The hope that we can fight cancer by influencing emotional states appears to have been misplaced." In the study, a patient's emotional status had no bearing on survival, regardless of gender, tumour site or disease stage. Julia Frater, of Cancer Research UK, said: "People with cancer can feel under pressure to cope well with their disease and treatment and to stay on top of things. They are often urged to feel positive. "These results should reassure them that if they don't feel like this, it's okay. Many people do feel worried or low following a diagnosis and this isn't likely to affect the outcome of their treatment." (C)BBC
Perfectionists are more prone to developing irritable bowel syndrome (IBS) after an infection, a study has suggested. University of Southampton researchers asked 620 people with gastroenteritis about stress and their illness. Those who pushed themselves or were particularly anxious about symptoms were more likely to develop IBS. Experts said the study, published in Gut, may explain why only some people develop IBS after a gut infection. Up to one in 10 people develop it after a having a bacterial gut infection, having previously been healthy. Such infections cause inflammation and ulceration in the bowel and can cause severe vomiting and rectal bleeding. In this study, each person was checked three and six months after their initial bout of bacterial gastroenteritis to see if they had developed IBS symptoms such as diarrhoea, constipation, abdominal pain and bloating. In all, 49 people had IBS at both points. Women were more than twice as likely to have IBS as the men. Those with IBS were significantly more likely to have reported high levels of stress and anxiety and psychosomatic symptoms than those who did not develop the condition. They were also significantly more likely to be "driven", carrying on regardless until they were forced to rest, which the researchers say simply makes the initial condition worse and longer-lasting, potentially leading to IBS. (C)BBC
Some cases of chronic fatigue syndrome could be due to brain "injuries" caused during the early stages of glandular fever, scientists suggest. A University of New South Wales team has followed people with Epstein-Barr virus since 1999. They suggest those who remained ill after the virus had gone had suffered a "hit-and-run injury" to the brain. Writing in the Journal of Infectious Diseases, they said the brain appears to keep behaving as if a person is ill. Epstein-Barr virus causes glandular fever, sometimes known as "the kissing disease". Symptoms include fever, sore throat, tiredness, and swollen lymph glands. Most patients recover within a few weeks but one in 10 young people will suffer prolonged symptoms, marked by fatigue. If these symptoms persist, to a disabling degree for six months or more, the illness may be diagnosed as chronic fatigue syndrome (CFS). The researchers followed the course of illness among 39 people diagnosed with acute glandular fever. Eight patients developed a "post-infective fatigue syndrome" lasting six months or longer, while the remaining 31 recovered quickly. The scientists then looked for signs of the Epstein-Barr virus in blood samples collected from each individual over 12 months. Professor Andrew Lloyd, of the research team, said: "Our findings reveal that neither the virus nor an abnormal immune response explain the post-infective fatigue syndrome. (C)BBC
A team of scientists at the Weizmann Institute of Science, led by Prof. Michal Schwartz of the Neurobiology Department, has come up with new findings that may have implications in delaying and slowing down cognitive deterioration in old age. The basis for these developments is Schwartz's team's observations, published today in the February issue of Nature Neuroscience, that immune cells contribute to maintaining the brain's ability to maintain cognitive ability and cell renewal throughout life. Until quite recently, it was generally believed that each individual is born with a fixed number of nerve cells in the brain, and that these cells gradually degenerate and die during the person's lifetime and cannot be replaced. This theory was disproved when researchers discovered that certain regions of the adult brain do in fact retain their ability to support and promote cell renewal (neurogenesis) throughout life, especially under conditions of mental stimuli and physical activity. One such brain region is the hippocampus, which subserves certain memory functions. But how the body delivers the message instructing the brain to step up its formation of new cells is yet unknown. The central nervous system (CNS), comprising the brain and spinal cord, has been considered for a long time as "a forbidden city", in which the immune system is denied entry as its activity is perceived as a possible threat to the complex and dynamic nerve cell networks. Furthermore, immune cells that recognize the brain's own components("autoimmune" cells) are viewed as a real danger as they can induce autoimmune diseases.
Patients with panic disorder have nearly double the risk for coronary heart disease, and those also diagnosed with depression are at almost three times the risk, according to new research. The study in the current issue of Psychosomatic Medicine focuses on the medical histories of nearly 40,000 people from the time they were first diagnosed as suffering from panic disorder. Lead author Andres Gomez-Caminero, Ph.D., says the large cohort study "highlights, for the first time, the potential for additive effects of different psychiatric conditions on cardiovascular health….and it really sets the foundation for new research in the area of cardiovascular risk estimation among patients with mental illness." The report focuses on medical histories from a database of 17 million patients jointly maintained by 30 managed care providers. Panic disorder involves unexpected and repeated episodes of intense fear accompanied by physical symptoms including chest pain, heart palpitations, shortness of breath, dizziness or abdominal distress. Panic disorder patients are more likely to be female, overweight, smokers and have a history of depression. About 2.4 million Americans annually experience panic episodes, and the manifestations often mimic symptoms of a heart attack. The disorder can be treated by medications and psychotherapy.
Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 7943 - Posted: 09.24.2005
By NICHOLAS BAKALAR Using brain scanning techniques, researchers have located a specific part of the brain that causes people with asthma to wheeze and gasp for breath when under emotional stress. Their report, released on Aug. 29, will appear in the Sept. 13 issue of The Proceedings of the National Academy of Sciences. Asthma sufferers often note that anxiety and emotional turmoil make the symptoms of an attack much worse, and in some cases, emotion alone can precipitate an attack. Previous research has shown, for example, that college students with asthma have greater airway inflammation when they are exposed to an allergen during exam week than when the exposure occurs at a less stressful time. Though these psychological exacerbations of asthma were well known, the physical connection between the brain and the immune system had not been described. Richard J. Davidson, the senior author of the paper and a professor of psychology and psychiatry at the University of Wisconsin, said the work showed that when people with asthma are exposed to their allergen, "you find certain centers in the brain that we know are intimately involved in emotions that get activated." Copyright 2005 The New York Times Company
MADISON -- The mere mention of a stressful word like "wheeze" can activate two brain regions in asthmatics during an attack, and this brain activity may be associated with more severe asthma symptoms, according to a study by University of Wisconsin-Madison researchers and collaborators. The study, which appears in the Proceedings of the National Academy of Sciences (Online, August 29, 2005), reveals a functional link between emotion processing centers in the brain and certain physiological processes relevant to disease. UW-Madison psychology professor Richard Davidson, an expert on emotions; and UW-Madison medicine professor William Busse, an expert on asthma; are senior co-authors on the study. Melissa Rosenkranz, a graduate student at the UW-Madison Laboratory for Affective Neuroscience, is the lead author. "While this study was small, it shows how important specific brain circuits can be in modulating inflammation," says Davidson, director of the affective neuroscience laboratory and the Waisman Laboratory for Functional Brain Imaging and Behavior. "The data suggest potential future targets for the development of drugs and behavioral interventions to control asthma and other stress-responsive disorders."
New York University biologists have uncovered how the innate immune system in mice's brains fights viral infection of neurons. The findings, published as the cover study in the latest issue of Virology, show that proteins in neurons fight the virus at multiple stages--by preventing the formation of viral RNA and proteins, and blocking the virus' release, which could infect other cells in the brain. "There is no magic bullet in fighting viral infections in neurons," said NYU Biology Professor Carol Shoshkes Reiss, the study's senior author. "However, these findings show the redundancy of the immune system--when one response fails to fight infection, others step in." The study was also conducted at NYU, by a post-doctoral fellow, Mark Trottier, Jr., PhD, now at Michigan State, and Beth Palian, currently a doctoral student at the University of Southern California. Recently, the West Nile virus has been responsible for a viral encephalitis outbreak in the northeast. The NYU researchers set out to determine how the body can fight viral encephalitis. Specifically, they examined how type I interferons--proteins made by the body that are released in response to stimuli, notably infection--work in neurons and to determine if nerve cells' response to interferons is similar to that of other cells.
Curious female rats, more willing to step out and explore their environment, survive breast and pituitary tumors longer than their more cautious sisters, says a Penn State researcher. Dr. Sonia Cavigelli, assistant professor of biobehavioral health, says that her study of 80 female rats from birth to death shows that the curious ones with tumors lived, on average, an additional six months, or 25 percent longer lives, than the cautious ones. "It's difficult to extrapolate from rats to people,Ó she notes.ÒHowever, there have been studies that show that shy elderly people report more health symptoms than their more outgoing age-mates. Our new results with rats are consistent with those findings and support the notion that personality traits may have a significant impact on health and resilience to disease." Cavigelli, who joined the Penn State faculty in August, detailed the results at the American Psychosomatic Society meeting in Vancouver, Canada, in a paper, Exploratory Tendency During Infancy and Survival in Female Rats with Spontaneous Tumors. She conducted the study while she was a postdoctoral researcher at the University of Chicago. Her co-authors are J. R. Yee, graduate student in human development, and Dr. Martha McClintock, professor of psychology, both at the University of Chicago.
Up to three in 10 people who are injured do not recover as quickly as expected for psychological reasons, according to new study. In 5% to 10% of cases a minor physical injury becomes a major problem, affecting insurance claims and the length of time off work, it found. The work was done for the Association of British Insurers and International Underwriting Association. Insurers want to intervene earlier to prevent cases becoming too expensive. The report found that the recovery of between 20% and 30% of people injured in car accidents or at work was hampered by psychological factors. The organisations commissioned the research after evidence showed factors such as depression were affecting people's recovery from accidents. The report said the problem helps to explain why many injury claims take much longer to settle and at far greater cost than first seemed likely. Chief executive of the Motor Insurers' Bureau Ashton West, who chaired the research panel, said insurers would usually expect injuries such as back sprain or whiplash to clear up quickly. (C)BBC
Related chapters from BP7e: Chapter 16: Psychopathology: Biological Basis of Behavior Disorders; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 12: Psychopathology: The Biology of Behavioral Disorders; Chapter 11: Emotions, Aggression, and Stress
Link ID: 5898 - Posted: 07.28.2004