November 27, 2007, 10:00 PM CT

Compounds Improves Brain Function In Rodents

MIT scientists have shown that a cocktail containing three compounds normally in the blood stream promotes growth of new brain connections and improves cognitive function in rodents. The therapy is now being tested in Alzheimer's patients and could hold promise for other brain diseases and injuries.

The mixture, which includes a type of omega-3 fatty acid, is part of a new approach to attacking Alzheimer's. That approach focuses on correcting the loss of synapses, or connections between neurons, which characterizes the disease.

For the past 30 years, scientists have tried targeting the clumps of misfolded proteins, known as amyloid beta plaques, found in the brains of Alzheimer's patients. However, that approach has not yielded any effective therapys for the disease, which affects an estimated four million to five million Americans.

"It's been very frustrating," said Richard Wurtman, the Cecil H. Green Distinguished Professor of Neuropharmacology and senior author of a paper on the new work reported in the recent issue of Brain Research. "Nobody has demonstrated that if you prevent formation of the amyloid, people get better".

In December, a group of Alzheimer's researchers, including Wurtman, will participate in a symposium with the goal of developing a public policy to promote new approaches to Alzheimer's research. Organizers of the symposium think that the current system of dementia research is "broken" and needs to be fixed......... Posted by: Emily      Read more         Source

November 19, 2007, 8:11 PM CT

Use of intraoperative MRI in neurosurgery

Eventhough the use of intraoperative MRI can add time to surgical procedures, it can help surgeons detect residual disease and, if needed, modify their plan for surgery while the patient is on the operating room table, as per a research studyconducted by scientists at the University Hospitals of Cleveland/Case Western Reserve University in Cleveland, OH and Johns Hopkins University in Baltimore, MD.

The study included 122 patients between the ages of 6-77 who underwent 130 neurosurgical and ear, nose and throat procedures, including 106 craniotomies and 17 pituitary resections. The study showed that 73% of the patients who had undergone intraoperative MRI had additional surgical resection based on the intraoperative findings, said Jonathan Lewin, MD, lead author of the study. Each patient had between one and five intra-or postoperative imaging sessions which were between 1.7 seconds to 8 minutes. As per the study, the added total imaging time per case was around 35 minutes.

While neurosurgeons and neuroradiologists have been enthusiastic about the potential of intraoperative MRI, no one had investigated the additional time mandatory to add this to a routine neurosurgical case, Dr. Lewin said. With the development of several technological advances geared toward limiting the time required, our goal was to quantitatively measure the impact on surgery from both the time perspective and the benefit of this additional information, he said......... Posted by: Emily      Read more         Source

November 19, 2007, 8:08 PM CT

How men and women cope differently under stress

As per a research studythat appears in the current issue of SCAN (Social Cognitive and Affective Neuroscience), scientists at the University of Pennsylvania School of Medicine discuss how men and women differ in their neural responses to psychological stress.

We observed that different parts of the brain activate with different spatial and temporal profiles for men and women when they are faced with performance-related stress, says J.J. Wang, PhD, Assistant Professor or Radiology and Neurology, and lead author of the study.

These findings suggest that stress responses may be fundamentally different in each gender, sometimes characterized as fight-or-flight in men and tend-and-befriend in women. Evolutionarily, males may have had to confront a stressor either by overcoming or fleeing it, while women may have instead responded by nurturing offspring and affiliating with social groups that maximize the survival of the species in times of adversity. The fight-or-flight response is linked to the main stress hormone system that produces cortisol in the human body the hypothalamic-pituitary-adrenal (HPA) axis.

Thirty-two healthy subjects 16 females and 16 males received fMRI (functional Magnetic Resonance Imaging) scans before, during and after they underwent a challenging arithmetic task (serial subtraction of 13 from a 4 digit number), under pressure. To increase the level of stress, the scientists frequently prompted participants for a faster performance and asked them to restart the task if they responded incorrectly. As a low stress control condition, participants were asked to count backward without pressure......... Posted by: Emily      Read more         Source

Tue, 20 Nov 2007 01:35:16 GMT

Why We All Stink as Intuitive Psychologists

Many people quite naturally believe they are good ''intuitive psychologists'', thinking it is relatively easy to predict other people''s attitudes and behaviours. We each have information built up from countless previous experiences involving both ourselves and others so surely we should have solid insights?

No such luck.

In reality people show a number of predictable biases when estimating other people''s behaviour and its causes. And these biases help to show exactly why we need psychology experiments and why we can''t rely on our intuitions about the behaviour of others.

One of these biases is called the false consensus bias. In the 1970s Stanford University social psychologist Professor Lee Ross set out to show just how the false consensus bias operates in two neat studies (Ross, Greene & House, 1977).

False consensus
In the first study participants were asked to read about situations in which a conflict occurred and then told two alternative ways of responding. They were asked to do three things:

• Guess which option other people would choose,
• Say which option they would choose,
• Describe the attributes of the person who would choose each of the two options.

The results showed more people thought others would do the same as them, regardless of which of the two responses they actually chose themselves. This shows what Ross and colleagues dubbed the ''false consensus'' bias - the idea that we each think other people think the same way we do when actually they often don''t.

Another bias emerged when participants were asked to describe the attributes of the person who made the opposite choice to their own. Compared to other people who made the same choice they did, people made more extreme predictions about the personalities of those who made didn''t share their choice.

To put it a little crassly: people tend to assume that those who don''t agree with them have something wrong with them! It might seem like a joke, but it is a real bias that people demonstrate.

Eat at Joe''s!
While the finding from the first study is all very well in theory, how can we be sure people really behave the way they say they will? After all, psychologists have famously found little connection between people''s attitudes and their behaviour.

In a second study, therefore, Ross and colleagues abandoned hypothetical situations, paper and pencil test and instead took up the mighty sandwich board.

This time a new set of participants, who were university students, were asked if they would be willing to walk around their campus for 30 minutes wearing a sandwich board saying: "Eat at Joe''s". (No information is available about the food quality at ''Joe''s'', and consequently how foolish students would look.)

For motivation participants were simply told they would learn ''something useful'' from the study, but that they were absolutely free to refuse if they wished.

The results of this study confirmed the previous study. Of those who agreed to wear the sandwich board, 62% thought others would also agree. Of those who refused, only 33% thought others would agree to wear the sandwich board. Posted by: Jerry      Read more     Source

November 18, 2007, 9:06 PM CT

Blood clotting protein linked to rheumatoid arthritis

Scientists at Cincinnati Childrens have issued the first study showing that a protein normally involved in blood clotting (fibrin), also plays an important role in the inflammatory response and development of rheumatoid arthritis. Inflammatory joint disease appears to be driven by the engagement of inflammatory cells with fibrin matrices through a specific integrin receptor, aMB2. Writing in the recent issue of The Journal of Clinical Investigation, scientists suggest that therapies designed to interrupt the localized interaction of inflammatory cells and fibrin may help arthritis patients.

Our study establishes that fibrin is a powerful, eventhough context-dependent, determinant of inflammatory joint disease, said Jay Degen, Ph.D., a researcher in Developmental Biology at Cincinnati Childrens and the studys lead author. These findings also suggest that pharmacologically interrupting the interaction of fibrin and aMB2 might be efficacious in the therapy of arthritic disease as well as a number of other inflammatory diseases, such as multiple sclerosis.

Affecting 2.1 million people in the United States, rheumatoid arthritis is a painful and debilitating disease involving chronic inflammation, tissue degeneration, loss of cartilage and bone and ultimately loss of joint mobility and function, as per the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Eventhough the diseases precise cause is not fully known, activation of specific components in the bodys immune system seem to play a major role in its onset and early progression, as per researchers. Fibrin deposits are a prominent feature of arthritic joints and the protein appears to be a link between systems that control inflammation and bleeding within joints. Dr. Degen and colleagues explained that in arthritic joints, the mesh-like matrices formed by fibrin to create blood clots may control local activity of inflammatory cells as well as support inappropriate tissue reorganization......... Posted by: Emily      Read more         Source

November 18, 2007, 8:43 PM CT

First study of Australia's high cost of pain

For the first time, a dollar value has been attached to the high cost of pain in Australia in an MBF Foundation funded study that reveals a massive annual cost of $34.3 billion -- nearly $11,000 for each of the estimated 3.2 million people grappling with pain. The price tag of pain includes both financial costs and loss of healthy life.

The MBF Foundation study The High Price of Pain: The Economic Impact of Persistent Pain in Australia, conducted by Access Economics in collaboration with the University of Sydney Pain Management Research Institute also observed that the people who are suffering from persistent pain are carrying more than half of its overall cost burden. The Foundation has called for pain to be treated as a health priority with a co-ordinated national response.

Findings from the study will be used to identify the best ways to ease suffering, save healthcare dollars and help patients maintain productive lives.

Dr Christine Bennett, MBF chief medical officer and chair of the MBF Foundation Steering Committee, said that establishing the economic cost of pain to Australia was a very significant development for healthcare strategy.

The impact and cost of persistent pain is so widespread that a national approach is needed to address this major health issue and its hidden health burden, Dr Bennett said. This is vital because pain is involved across many existing National Health Priority Areas such as cardiovascular disease, cancer, musculoskeletal disease and diabetes......... Posted by: Emily      Read more         Source

November 15, 2007, 10:11 PM CT

CT colonography detects extracolonic abnormalities

When used in elderly patients, can detect a high number of new and significant abnormalities outside the colon (including cirrhosis and tumors) and is well tolerated, as per a recent study conducted by scientists at St. Jamess University Hospital in Leeds, United Kingdom (UK).

We decided to target older patients (over age 70) with lower gastrointestinal tract symptoms, who were referred to radiology for work up, as this group generally tolerates barium enema examinations less well than those under age 70, said Damian Tolan, MD, lead author of the study. Our study centered on the initial analysis of CT colonography examinations in this patient group. We only looked for significant pathology, excluding common non-malignant incidental findings; for example gallstones or adrenal adenomas. It is important to note that CT colonography is not used for colorectal cancer screening in the UK and is reserved for symptomatic patients only, he said.

The study included 400 patients, who underwent CTC over a 14-month period. The study found 100 significant lesions that were previously unknown in 96 patients. The study also showed that 49 of the patients had at least one malignancy, including 23 extracolonic malignancies and 29 colorectal malignancies.

Lower gastrointestinal symptoms in older patients over 70 are less specific for colorectal cancer than in younger patients. In our study, patients had a high yield for significant colonic pathology, including colon cancer and advanced adenomas, said Dr. Tolan. While these would almost certainly have been detected by colonoscopy and barium enema, CT colonography detected a wide range of other abnormalities as well, he said.In all, 29% of patients had significant pathology outside the colon, and in 24% this was a newly diagnosed condition. These included gastric, lung and renal cancers (5.8%), complications of diverticular disease (2%) and a range of other conditions from abdominal aortic aneurysms to cirrhosis, he said......... Posted by: Emily      Read more         Source

November 15, 2007, 10:05 PM CT

Bad to the bone: shed light on osteoporosis

Ten million people in the United States are estimated to already have bone diseases, and almost 34 million more are estimated to have low bone mass, putting them at increased risk for osteoporosis, as per the National Osteoporosis Foundation.

Liyun Wang, assistant professor of mechanical engineering at the University of Delaware, knows the serious consequences of osteoporosis.

Two of Wang's aunts have suffered from the insidious bone-thinning disease, and one aunt died within a year after falling and fracturing her hip.

Wang is now leading research that will shed light on how osteocytes--the cells encased inside your bones--sense external stimuli and communicate with cells on the surface, signaling them to either build more bone or remove existing bone.

The five-year, $1.6 million project, ranked in the top 5 percent of research proposals recommended for funding by the National Institutes of Health (NIH) this year, holds promise in unveiling the mysteries of bone and joint diseases afflicting people worldwide.

The results may not only help researchers home in on the cause of osteoporosis and arthritis, but also develop more effective drug therapies to treat the debilitating bone and joint diseases.

The project will involve an interdisciplinary team of researchers at UD, including Prof. Mary C. Farach-Carson and Associate Prof. Randall Duncan, who hold primary appointments in biological sciences with joint appointments in mechanical engineering, and John Novotny, assistant professor of mechanical engineering......... Posted by: Emily      Read more         Source

November 14, 2007, 9:55 PM CT

Left brain helps hear through the noise

Our brain is very good at picking up speech even in a noisy room, an adaptation essential for holding a conversation at a cocktail party, and now we are beginning to understand the neural interactions that underlie this ability. An international research team reports today, in the online open access journal BMC Biology, how investigations using neuroimaging have revealed that the brain's left hemisphere helps discern the signal from the noise.

In our daily lives, we are exposed to a number of different sounds from multiple sources at the same time, from traffic noise to background chatter. These noisy signals interact and compete with each other when they are being processed by the brain, a process called simultaneous masking. The brain's response to masking stimuli brings about the 'cocktail-party effect' so that we are able to hear a particular sound, even in presence of a competing sound or background noise.

Hidehiko Okamoto and his colleagues of the Institute for Biomagnetism and Biosignal analysis, Muenster, Gera number of, and his colleagues in Japan and Canada have used a neuroimaging technique known as magnetoencephalography (MEG) to follow the underlying neural mechanisms and hemispheric differences correlation to simultaneous masking as volunteers listened to different combinations of test and background sounds. Test sounds were played either to the left or to the right ear, while the competing noise was presented either to the same or to the opposite ear......... Posted by: Emily      Read more         Source

November 14, 2007, 9:44 PM CT

Menstruation proves more than a curse

The cells which thicken the womb wall during a woman's menstrual cycle contain a newly discovered type of stem cell, and could be used in the therapy of damaged and/or old tissue, as per research published recently in the online open access publication, Journal of Translational Medicine.

Dr Xiaolong Meng of the Bio-Communications Research Institute in Wichita, Kansas, led the research team consisting of researchers from the University of Alberta, University of Western Ontario and Medistem Laboratories (mdsm.ob). The team identified a new type of stem cell that can be reproducibly isolated from menstrual blood collected from healthy female subjects.

"We have a number of problems with our current methods of stem cell treatment, like those taken from bone marrow," commented Dr Meng, "They may be rejected by the recipient and/or have limited potential to generate new tissue. Now we've found a possible new way to overcome these difficulties by using cells from menstrual blood."

The growth of new blood vessels from pre-existing blood vessels is an essential part of the uterine or womb phase of the menstrual cycle. Cells collected from the menstrual blood of women include types which can be cultured in the laboratory, which replicate almost 70 times in a very rapid time span. This replication rate is far faster than cells which are currently used, taken from umbilical cord blood and bone marrow. The cells are so unique in their ability to develop into at least 9 different cells including heart, liver and lung, that scientists called the cells Endometrial Regenerative Cells (ERC). Not only do ERC replicate at a phenomenal rate of almost every 20 hours, but they produce unique growth factors at a rate of almost 100,000 greater than cells from umbilical cord blood......... Posted by: Emily      Read more         Source