Leukodystrophy

Leukodystrophy refers to a group of disorders characterized by progressive degeneration of the white matter of the brain. The leukodystrophies are caused by imperfect growth or development of the myelin sheath, the fatty covering that acts as an insulator around nerve fibers. Myelin, which the white matter of the brain takes its colour from, is a complex substance made up of at least ten different chemicals. Each of the leukodystrophies is the result of a defect in the gene that controls the production or metabolism of one of the component molecules of myelin.

The word leukodystrophy comes from the Greek roots leuko, white, dys, lack of, and troph, growth. Thus leukodystrophy describes a set of diseases that affect the growth or maintenance of the white matter.

Wolff-Parkinson-White

Wolff-Parkinson-White syndrome (WPW) is a syndrome of pre-excitation of the ventricles of the heart due to an accessory pathway known as the bundle of Kent. This accessory pathway is an abnormal electrical communication from the atria to the ventricles.

The incidence of WPW syndrome is between 0.9 and 3% of the general population.

While the vast majority of individuals with a bundle of Kent remain asymptomatic throughout their entire lives, there is a risk of sudden death associated with the syndrome. Sudden death due to WPW syndrome is rare (incidence of less than 0.6%), and is due to the effect of the accessory pathway on tachyarrhythmias in these individuals.

Coping with Disasters

After any type of disaster, people feel relieved to be alive. But then they often feel stress, fear and anger. Most people will also find that they can't stop thinking about what happened. These feelings and memories aren't a sign of personal weakness. Most trauma survivors have stress reactions for days or weeks. But some people have long-term problems, including

* Post-traumatic stress disorder
* Depression
* Self-blame
* Suicidal thoughts
* Alcohol or drug abuse

If you've survived a disaster, talk to your family and friends when you are ready. Most people recover from trauma naturally over time. If your emotional reactions are getting in the way of your relationships, work, or other important activities, you might want to talk to a counselor or your doctor. Treatments are available.

Influenza Diseases

Influenza is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death. The best way to prevent the flu is by getting a flu vaccination each year. Every year in the United States, on average 5% to 20% of the population gets the flu; more than 200,000 people are hospitalized from flu complications, and; about 36,000 people die from flu-related causes. Some people, such as older people, young children, and people with certain health conditions, are at high risk for serious flu complications.

here are two main types of influenza virus: Types A and B. Influenza A and B viruses are responsible for seasonal flu epidemics each year. Influenza A viruses can be broken down into sub-types. Over the course of a flu season, different types (A & B) and subtypes of influenza A viruses can circulate and cause illness. In addition, influenza viruses are constantly changing through a process called "antigenic drift."