View clinical trials related to Abnormalities.
Filter by:Background: - Patellofemoral pain syndrome is one of the most common knee problems. It is characterized by pain in the front of the knee that is aggravated by deep knee flexion, prolonged sitting, and repetitive movement. The most widely accepted theory regarding the source of this pain is that a force imbalance around the knee puts extra stress on the area, leading to pain. - Researchers are interested in learning more about the muscle groups around the knee to better understand the causes of knee pain. Objectives: - To obtain more information on how muscles, tendons, and bones work together to cause motion in the knee, both in the normal state and after immobilizing certain muscles around the knee. Eligibility: - Healthy individuals between the ages of 18 and 55, who have no current or chronic muscle, bone, or joint problems and who have no implants or other problems that would prevent them from receiving a magnetic resonance imaging (MRI) scan. Design: - This protocol will be carried out over two visits, both of which will involve using standard MRI sequences to look at the knee at rest and in motion. - The first part will examine the knee under its natural state, with a standard MRI scan of the knee both at rest and in motion. - The second part will involve temporarily reducing the force producing capabilities of one of the extensor muscles in the knee. To do so, study doctors will inject lidocaine into the muscle, which will temporarily (for approximately 2 hours) block the force producing capacity of this muscle, and then perform the MRI scan.
Effective treatment and prevention strategies for childhood stroke and porencephaly can only be developed once the causes are understood. There is increasing evidence that inherited and acquired coagulation abnormalities alone or in combination with environmental factors, predispose to arterial and venous thrombosis. Inherited abnormalities of factor V Leiden, prothrombin, protein C, protein S, and antithrombin III may account for many of these thromboses. At present there is little information on the existing distribution of these coagulation anomalies in children with thrombosis. Recent reports also suggest that these clotting abnormalities may be responsible for some instances of intracranial hemorrhage, porencephaly, cerebral palsy and fetal death. This study will measure the frequency of several coagulation factor abnormalities (factor V Leiden, prothrombin 20210A, protein C, protein S, antithrombin III, and antiphospholipid antibodies) in children with a history of porencephaly and stroke, and will compare these to the prevalence of these mutations in population controls and family members. We will also describe the exogenous conditions which in concert with these coagulation factors, may have led to the development of thrombosis in these children....
The purpose of this research is to study a new way to test for chromosome abnormalities. Chromosomes are strands of DNA (the genetic material in the cell nucleus) that are made up of genes-the units of heredity. Chromosome abnormalities are usually investigated by staining the chromosomes with a dye (Giemsa stain) and examining them under a microscope. This method can detect many duplications and deletions of pieces of chromosomes and is very accurate in diagnosing certain abnormalities. It is not useful, however, for identifying very small abnormalities. This study will evaluate the accuracy of a test method using 24 different dyes for finding small chromosome abnormalities. Children and adults with various chromosome abnormalities may be eligible for this study, including, for example, people with developmental delay or mental retardation, abnormal growth features or growth retardation, and certain behavioral disorders. Participants will be evaluated in the clinic over a 1- to 3-day period, depending on their symptoms. All participants will be examined by a genetics specialist and will have a physical examination and possibly X-rays, computerized tomography (CT) scans, magnetic resonance imaging (MRI), ultrasound studies and medical photography. Blood will be drawn for chromosome testing-about 3 tablespoons from adults and 1 to 3 teaspoons from children. When the test results are available, participants will return to the clinic for follow-up evaluation and review of the test findings. The genetic and medical evaluations, along with their implications, will be discussed.