Keeping you up to date on recent headlines in neurology.

New PD study to image pre-treatment brain ... Parkinson's disease (PD), a debilitating movement disorder, is usually controlled by using drugs that compensate for a lack of the neurotransmitter dopamine. PD patients have a deficit of this important chemical because of degeneration in an area of the brain stem where it is made — a structure called the substantia nigra. A team of researchers led by David Vaillancourt, associate professor of kinesiology at the University Of Illinois at Chicago, hope that tests using functional and high-resolution structural brain imaging will reveal new clues about early PD. They've been awarded a two-year, $855,000 National Institutes of Health grant to do the work. "What's not well understood is how the structure and function of the basal ganglia, or other parts of the brain, are affected early on in the disease," said Vaillancourt. Vaillancourt will recruit 25 subjects with early signs of PD who haven't yet begun taking drugs to control the disease. Their study will compare findings to a control group matched for age, gender and handedness — because all subjects will perform motor tasks with their hands while their brain is being imaged. Vaillancourt's group wants to study what is happening before PD patients begin treatment with drugs such as levodopa that can change the way the brain functions. Pre-treatment brain scans may be useful to develop markers for screening and diagnosis.

Scientist builds tools to monitor brain signals ... Understanding the inner workings of the brain remains one of the last frontiers in all of neurobiology. A Case Western Reserve University (Cleveland) engineering professor is developing a miniaturized low-power device to detect how electrical signals and neurotransmitters in the brain work. Pedram Mohseni, assistant professor of electrical engineering and computer science at Case School of Engineering, was awarded a $675,000 Faculty Early Career Development grant from the National Science Foundation to pursue the project. Specifically in this CAREER project, Mohseni will develop a miniaturized low-power device for brain use to support neurobiological experiments in small laboratory animals. This new instrument will simultaneously record 16 channels of chemical and electrical neural activity in the brain from multiple microsensors, measuring neurotransmitters and action potentials in real time, as these signals happen, during behavior. An engineering method called very-large-scale-integration (VLSI) will be used to fabricate the device, roughly the size of a common cold capsule. VLSI is the same fabrication process used to create integrated circuits that are at the heart of today's consumer electronics and portable devices such as personal cell phones and computers.

High protein diet may shrink brain ... Researchers observing the effects of various diets on the brains of genetically engineered mice bred for studying Alzheimer's disease (AD) found quite unexpectedly that mice fed a high protein, low carbohydrate diet, developed brains that were five per cent lighter than those of mice fed other diets. The study was the work of researchers at The Mount Sinai School of Medicine (New York) and colleagues. The study is published in the journal Molecular Neurodegeneration. Many other studies have already suggested that low calorie, low fat diets rich in vegetables, fruits, and fish may delay or slow down AD, so researchers decided to take this a step further and compare the effects of several different diets on mice that were genetically engineered to have some of the disease characteristics of AD. Beta amyloid is a protein fragment snipped from an amyloid precursor protein (APP), whose role in the brain is not fully understood. What we do know is that in a healthy brain, beta amyloid fragments are broken down and eliminated, but in Alzheimer's disease, they build up and form hard, insoluble plaques. For the study, researchers tested four different diets on mice that were genetically engineered to express a mutant form of APP. To their surprise, they found that the brains of the mice that had been fed the high protein/low carbohydrate diet were five per cent lighter than those of mice on the other diets, and regions of the hippocampus were less developed. However, until they test for this effect in non-genetically engineered mice, it remains unclear whether the loss of brain mass is linked to the type of plaque found in AD.

Evidence given to back extension of stroke treatment window ... An article published online and in the December edition of The Lancet Neurology adds further evidence to back the extension of the treatment window for stroke using alteplase to 4.5 hours. Currently, the drug is only licensed for use in the 0-3 hour window following stroke. The article is written by researchers from the department of neurology, University of Heidelberg (Germany). Previously published research from ECASS III has shown that alteplase leads to better outcomes than placebo in stroke patients in the 3.0-4.5 hour window post stroke. In this study, the authors did secondary analyses using different endpoints to confirm or refute the efficacy and safety outcomes in the primary analysis in ECASS III. They also looked for evidence of confounding factors or subgroups that might differentially affect treatment outcome. The authors conclude: "Our results support the use of this thrombolytic drug in the extended period across a broad range of patient subgroups who meet the requirements of the European product label but miss the approved treatment window of 0-3 hours. Even with these encouraging findings, the most important principle of acute stroke intervention should, however, not be lost – that is, time remains critical and fast treatment still provides the greatest chance of recovery."

Tailored physical therapy helps restore more functions ... New research suggests a tailored approach to physical therapy after a neurological injury such as a stroke, traumatic brain injury or spinal cord injury could help restore a wider variety of functions. Clinical physical therapy is a widely used treatment approach to help restore the motor function of patients following neurological injuries. Unfortunately many of the specific treatments used in the clinic only restore function to a specific task, and not to a wide range of everyday activities. This is also true in animal research where stand training only leads to better standing, step training only leads to better stepping, and so forth. Researchers at Georgetown University Medical Center (Washington) have investigated the effects of training rats with spinal cord injuries on a robotic device (Rodent Robotic Motor Performance System made by Robomedica (Irvine, California) that precisely guides the hindlimbs through a training pattern. "Our results show that increasing activity using a precise and repeatable physiologically relevant training pattern can modify overground locomotion," said Nathan Neckel, PhD, a post-doctoral fellow in the department of neuroscience. "These findings suggest that more accurate and precise exercises in the human physical therapy clinic may lead to the restoration of function in everyday tasks."

— Compiled by Rob Kimball, MDD