Month: December 2007

Myoclonus refers to a quick, involuntary muscle jerk. For example, hiccups are a form of myoclonus. So are the sudden jerks, or “sleep starts,” you may experience just before falling asleep. These forms of myoclonus occur in healthy people and rarely present a problem. But in some cases, more severe forms of myoclonus can be triggered by an underlying problem, such as a head or spinal cord injury, a stroke, a nervous system or metabolic disorder, lack of oxygen to your brain, an infection, ingestion of a toxin, a reaction to a medication or other medical problems. If the underlying problem that’s causing myoclonus — a medication, for example — can be eliminated, the myoclonus usually resolves, too. But some disorders that cause myoclonus, such as epilepsy or Alzheimer’s disease, aren’t reversible and treatment of associated myoclonus may not eliminate … Read more

Tremor is an involuntary, rhythmical, shaking movement, usually of the hands, lower arms, and head. Who gets it? Tremor occurs as a symptom of some neurological diseases, such as Parkinson’s disease and multiple sclerosis, and in people with diseases of or damage to the cerebellum.  Some people inherit this condition from a parent who has tremors, or develop it as a side effect of certain drugs or underlying disease.  Tremor can affect both men and women. What causes it? Tremor occurs when the muscles relax and contract repeatedly.  While most people experience a tremor at some time, usually because of fear or excitement, a number of neurological diseases that destroy nerve tissue cause uncontrollable tremor.  These include Parkinson’s disease and multiple sclerosis.  Other causes include stroke or head injury; Wilson’s disease, a hereditary disorder in which toxic levels of copper … Read more

Wilson disease causes the body to retain copper. The liver of a person who has Wilson disease does not release copper into bile as it should. Bile is a liquid produced by the liver that helps with digestion. As the intestines absorb copper from food, the copper builds up in the liver and injures liver tissue. Eventually, the damage causes the liver to release the copper directly into the bloodstream, which carries the copper throughout the body. The copper buildup leads to damage in the kidneys, brain, and eyes. If not treated, Wilson disease can cause severe brain damage, liver failure, and death. Wilson disease is hereditary. Symptoms usually appear between the ages of 6 and 20 years, but can begin as late as age 40. The most characteristic sign is the Kayser-Fleischer ring—a rusty brown ring around the cornea … Read more

The authors investigated the effects of green tea polyphenols, a group of naturally occurring chemical substances found in plants that have antioxidant properties, in an animal model of Parkinson’s disease. Parkinson’s disease is a progressive, degenerative disorder of the central nervous system, resulting from the loss of dopamine-producing brain cells, and there is presently no cure. According to Dr. Baolu Zhao, corresponding and senior author on this article, current treatments for Parkinson’s are associated with serious and important side effects. Their previous research has indicated that green tea possesses neuroprotective effects, leading Guo and colleagues to examine its effects specifically in Parkinson’s. The authors discovered that green tea polyphenols protect dopamine neurons that increases with the amount consumed. They also show that this protective effect is mediated by inhibition of the ROS-NO pathway, a pathway that may contribute to cell … Read more

The work shows that adenosine, a brain chemical most widely known as the cause of drowsiness, is central to the effect of deep brain stimulation, or DBS. The technique is used to treat people affected by Parkinson’s disease and who have severe tremor, and it’s also being tested in people who have severe depression or obsessive-compulsive disorder. Patients typically are equipped with a “brain pacemaker,” a small implanted device that delivers carefully choreographed electrical signals to a very precise point in the patient’s brain. The procedure disrupts abnormal nerve signals and alleviates symptoms, but doctors have long debated exactly how the procedure works. The new research, by a team of neuroscientists and neurosurgeons at the University of Rochester Medical Center, gives an unexpected nod to a role for adenosine and to cells called astrocytes that were long overlooked by neuroscientists. … Read more