Posts tagged neuroscience

 July 30, 2012

In the first human study of its kind, researchers found that using stem cells to re-grow craniofacial tissues—mainly bone—proved quicker, more effective and less invasive than traditional bone regeneration treatments.

Researchers from the University of Michigan School of Dentistry and the Michigan Center for Oral Health Research partnered with Ann Arbor-based Aastrom Biosciences Inc. in the clinical trial, which involved 24 patients who required jawbone reconstruction after tooth removal.

Patients either received experimental tissue repair cells or traditional guided bone regeneration therapy. The tissue repair cells, called ixmyelocel-T, are under development at Aastrom, which is a U-M spinout company.

"In patients with jawbone deficiencies who also have missing teeth, it is very difficult to replace the missing teeth so that they look and function naturally," said Darnell Kaigler, principal investigator and assistant professor at the U-M School of Dentistry. "This technology and approach could potentially be used to restore areas of bone loss so that missing teeth can be replaced with dental implants."

William Giannobile, director of the Michigan Center for Oral Health Research and chair of the U-M Department of Periodontics and Oral Medicine, is co-principal investigator on the project.

The treatment is best suited for large defects such as those resulting from trauma, diseases or birth defects, Kaigler said. These defects are very complex because they involve several different tissue types—bone, skin, gum tissue—and are very challenging to treat.

The main advantage to the stem cell therapy is that it uses the patient’s own cells to regenerate tissues, rather than introducing man-made, foreign materials, Kaigler said.

The results were promising. At six and 12 weeks following the experimental cell therapy treatment, patients in the study received dental implants. Patients who received tissue repair cells had greater bone density and quicker bone repair than those who received traditional guided bone regeneration therapy.

In addition, the experimental group needed less secondary bone grafting when getting their implants.

The cells used for the therapy were originally extracted from bone marrow taken from the patient’s hip. The bone marrow was processed using Aastrom’s proprietary system, which allows many different cells to grow, including stem cells. These stem cells were then placed in different areas of the mouth and jaw.

Stem cell therapies are still probably 5-10 years away from being used regularly to treat oral and facial injuries and defects, Kaigler said. The next step is to perform more clinical trials that involve larger craniofacial defects in a larger number of patients.

The study, “Stem cell therapy for craniofacial bone repair: A randomized, controlled clinical trial,” appears this month in the journal Cell Transplantation.

See the video here

Source: University of Michigan

July 30, 2012

UC Irvine scientists have discovered intriguing differences in the brains and mental processes of an extraordinary group of people who can effortlessly recall every moment of their lives since about age 10.

The phenomenon of highly superior autobiographical memory – first documented in 2006 by UCI neurobiologist James McGaugh and colleagues in a woman identified as “AJ” – has been profiled on CBS’s “60 Minutes” and in hundreds of other media outlets. But a new paper in the peer-reviewed journal Neurobiology of Learning & Memory’s July issue offers the first scientific findings about nearly a dozen people with this uncanny ability.

All had variations in nine structures of their brains compared to those of control subjects, including more robust white matter linking the middle and front parts. Most of the differences were in areas known to be linked to autobiographical memory, “so we’re getting a descriptive, coherent story of what’s going on,” said lead author Aurora LePort, a doctoral candidate at UCI’s Center for the Neurobiology of Learning & Memory.

Surprisingly, the people with stellar autobiographical memory did not score higher on routine laboratory memory tests or when asked to use rote memory aids. Yet when it came to public or private events that occurred after age 10½, “they were remarkably better at recalling the details of their lives,” said McGaugh, senior author on the new work.

"These are not memory experts across the board. They’re 180 degrees different from the usual memory champions who can memorize pi to a large degree or other long strings of numbers," LePort noted. "It makes the project that much more interesting; it really shows we are homing in on a specific form of memory."

She said interviewing the subjects was “baffling. You give them a date, and their response is immediate. The day of the week just comes out of their minds; they don’t even think about it. They can do this for so many dates, and they’re 99 percent accurate. It never gets old.”

The study also found statistically significant evidence of obsessive-compulsive tendencies among the group, but the authors do not yet know if or how this aids recollection. Many of the individuals have large, minutely catalogued collections of some sort, such as magazines, videos, shoes, stamps or postcards.

UCI researchers and staff have assessed more than 500 people who thought they might possess highly superior autobiographical memory and have confirmed 33 to date, including the 11 in the paper. Another 37 are strong candidates who will be further tested.

"The next step is that we want to understand the mechanisms behind the memory," LePort said. "Is it just the brain and the way its different structures are communicating? Maybe it’s genetic; maybe it’s molecular."

McGaugh added: “We’re Sherlock Holmeses here. We’re searching for clues in a very new area of research.”

Provided by University of California, Irvine

Source: medicalxpress.com

30 July 2012

Researchers from The University of Queensland’s Institute for Molecular Bioscience have discovered a potential new approach to treating chronic inflammatory diseases such as arthritis. 

Professor David Fairlie and his colleagues have developed an experimental treatment that has proven effective at reducing symptoms and stopping the progression of the disease in models of arthritis. 

“Human enzymes called proteases stimulate the secretion of immune cells that, when the correct amount is released, play important roles in digestion, fighting infections and healing wounds,” Professor Fairlie said. 

“But in chronic inflammatory diseases such as arthritis, these enzymes continuously stimulate the release of immune cells, which cause inflammation when present at high levels. This leads to ongoing tissue damage.” 

Professor Fairlie and his team have developed experimental compounds that block this stimulation and successfully reduce chronic inflammatory arthritis in experimental models. 

If the treatment could be transferred to humans, it has the potential to reduce both the health and economic impacts of chronic inflammatory diseases. 

Almost four million Australians suffer from chronic joint pain and disability caused by various forms of arthritis, including osteoarthritis, rheumatoid arthritis and gout. 

Related healthcare and loss of employment cost Australia over $20 billion per year, an amount that is expected to increase dramatically as our population ages. 

These promising new findings are published in the current hard-copy edition of The Federation of American Societies For Experimental Biology Journal, the world’s most cited scientific journal in biology. 

Journal subscribers can access the paper at this address: http://bit.ly/Pg8lgk

Source: The University of Queensland

July 30, 2012

Is attention-deficit/hyperactivity disorder (ADHD) due to a delay in brain development or the result of complete deviation from typical development? In the current issue of Biological Psychiatry, Dr. Philip Shaw and colleagues present evidence for delay based on a study by the National Institutes of Health.

The cerebral cortex is the folded gray tissue that makes up the outermost portion of the brain, covering the brain’s inner structures. This tissue has left and right hemispheres and is divided into lobes. Each lobe performs specific and vitally important functions, including attention, thought, language, and sensory processing.

Two dimensions of this structure are cortical thickness and cortical surface area, both of which mature during childhood as part of the normal developmental process. This group of scientists had previously found that the thickening process is delayed in children diagnosed with ADHD. So in this study, they set out to measure whether surface area development is similarly delayed.

They recruited 234 children with ADHD and 231 typically developing children and scanned each up to 4 times. The first scan was taken at about age 10, and the final scan was around age 17. Using advanced neuroimaging technology, they were able to map the trajectories of surface area development at over 80,000 points across the brain.

They found that the development of the cortical surface is delayed in frontal brain regions in children with ADHD. For example, the typically developing children attained 50% peak area in the right prefrontal cortex at a mean age of 12.7 years, whereas the ADHD children didn’t reach this peak until 14.6 years of age.

"As other components of cortical development are also delayed, this suggests there is a global delay in ADHD in brain regions important for the control of action and attention," said Dr. Shaw, a clinician studying ADHD at the National Institute of Mental Health and first author of this study.

"These data highlight the importance of longitudinal approaches to brain structure," commented Dr. John Krystal, Editor of Biological Psychiatry. "Seeing a lag in brain development, we now need to try to understand the causes of this developmental delay in ADHD."

Dr Shaw agrees, adding that this finding “guides us to search for genes that control the timing of brain development in the disorder, opening up new targets for treatment.”

Additional work expanding these measures into adulthood will also be important. Such data would help determine whether or when a degree of normalization occurs, or if these delays translate into long-lasting cortical deficits.

Provided by Elsevier

Source: medicalxpress.com