Posts Tagged ‘treatment’

Alzheimer’s Disease

May 11, 2010

Alzheimer’s disease is the most common form of dementia. Common symptoms include memory loss, confusion, irritability and aggression, mood swings and language breakdown. It is often misdiagnosed as senility. Progression of the disease varies widely. About 26.6 million people were diagnosed with Alzheimer’s in 2006.

There are two types of Alzheimer’s. Late-onset, or sporadic, Alzheimer’s is more common and is diagnosed in people 65 years of age or older. Early-onset, or familial Alzheimer’s disease (FAD), usually develops in adults in their 30’s and 40’s. This type only occurs in about 1 out of every 1000 Alzheimer’s cases. These individuals have a family history of FAD. Genetics has been linked to Alzheimer’s.

Genetics of Alzheimer’s

Genetics and Alzheimer’s are linked but the relationship is not completely understood. If a parent has been diagnosed with FAD, 50% of his offspring will develop it. It is due to autosomal dominant mutations. Therefore, even if a person has only one copy of the gene, he will develop that type. A person who has not developed the disease can not pass it on. Late-onset Alzheimer’s, on the other hand, is not inherited. There are, however, families in which clusters of cases exist.

Three genes have been discovered that influence a person’s risk of getting FAD. These include an amyloid precursor protein (APP) gene and two presenilin genes (PSEN-1 and PSEN-2). These genes exist on chromosomes 1, 14 and 21. A mutation on chromosome 21 causes a build-up in the amount of amyloid protein in the brain. An increase in the amount of amyloid protein has been linked to FAD. Mutations in all of these genes cause senile plaques.

Many genes affect a person’s chances of getting late-onset Alzheimer’s. Some genes are thought to have protective influence. A combination of multiple genes increases the risk of developing it. Only one gene has been identified so far. Apolipoprotein E (APOE) mutations are the cause of about 50% of all late-onset Alzheimer’s. It is found in three forms:

  • APOE2 gives a person some protection against getting Alzheimer’s.
  • APOE3 gives an individual an “average risk” of developing Alzheimer’s.
  • APOE4 increases a person’s risk of getting Alzheimer’s. People with one copy are four times more likely and those with two copies are ten times more likely to develop the disease. Having two copies, however, does not mean that a person will definitely get the disease.

Recent research has, however, made it possible to determine which genes have an influence on developing this disorder. It will only take time to identify these genes. The role of each gene will then be determined. It may then be possible to treat and prevent the disease.

Treatment of Alzheimer’s

Treatment is targeted at alleviating the symptoms of Alzheimer’s. Research has not yet discovered a way to prevent or delay the onset or progression of this condition. Clinical trials are ongoing. Some lifestyle changes that may help include exercise, mental stimulation and a healthy diet. Cardiovascular health and pharmaceutical products may also have an influence on one’s risk.

Cystic Fibrosis: Signs and Symptoms, Causes, Treatment

May 11, 2010

Cystic fibrosis (CF) is a genetic disease affecting the mucus glands of the lungs, pancreas, liver, sinuses, intestines and sex organs. Mucus, which is normally thin and watery, usually keeps tissues moist. Those who develop CF, however, have very thick mucus which results in frequent lung infections. This mucus can block ducts leading to the pancreas as well. Sweat glands are also affected.

Signs and Symptoms of Cystic Fibrosis

Genetic tests can identify individuals with a mutated gene even before they are born. Newborn genetic screening tests can detect the disease as well. Sweat tests must be performed after birth, however, to determine if the individual is a carrier or has the disease. 

Symptoms and severity differ from person to person. One individual may have terrible lung and digestive disorders. Others may not have any symptoms until later in life. Some symptoms include:

  • bloated feeling
  • deficiency in the fat-soluble vitamins A, D, E and K
  • greasy and/or bulky stools
  • intestinal gas
  • malnourished
  • poor growth
  • shortness of breath
  • stomach pain or discomfort.

In advanced cases lung and pancreatic disorders cause many problems. Mucus in the lungs harbors bacteria which cause lung infections and blocks airways making it difficult to breathe. Respiratory failure is a major problem.

Ducts in the pancreas are blocked by mucus as well. The pancreas normally produces digestive enzymes that break down food in the intestines. If the ducts are blocked, proteins and fats will not be metabolized correctly. When this happens, the person suffers from stomach and intestinal disquietude, malnutrition and abnormal stools.

People who have CF have sweat which is five times as salty as a healthy individual’s sweat. Their mineral balance can be upset if they perspire and lose large quantities of sodium, which is very important in the body’s normal functions. This loss can also result in a heat emergency or abnormal heart rhythms.

What Causes Cystic Fibrosis

Medical research has established a genetic link to cystic fibrosis. A single gene on chromosome 7 makes a protein called the cystic fibrosis transmembrane conductance regulator (CFTR). This gene is responsible for making sweat, mucus and digestive juices. This protein controls chloride ions going in and out of cells.

People who have cystic fibrosis have a mutation in the CFTR gene. This means that chloride ions are not capable of getting through the membrane of the cells. In most cases, however, the CFTR protein is missing. The shortened version is identified by the body and destroyed.

CF is inherited and is not contagious. It is a recessive disorder, meaning people with one normal gene and one mutated gene are carriers of the disease. Offspring must inherit the mutated gene from each parent to have symptoms. Offspring of two parents who are carriers have a 25% chance of developing the disease.

Treatment for Cystic Fibrosis

Treatment involves the use of antibiotics and clearing the mucus out of the lungs. They are prescribed enzymes to help them digest their food and obtain nutrients. Surgery is sometimes necessary to clear obstructions. Lung transplants may be required if tissue damage is too severe.

Progress toward a Cure

There is no cure for CF. Cystic fibrosis prognosis is not good. But research gives hope that there is an increasing life expectancy of people with CF. Recent developments in treating and curing the disease are under development. Gene therapy is in the future. This involves placing a normal CFTR gene in the infected cells.

Some other developments toward a cure target the metabolic pathways involved in the disease. These include:

  • Correcting the problems with the lining of the lungs to prevent infections
  • Improving the mucus so it is not so thick
  • New antibiotics
  • New medications to reduce the toxic effects of the inflammatory immune response.