View clinical trials related to Oculocutaneous Albinism.
Filter by:Serotonin (5-HT or 5-hydroxytryptamine) is a monoamine primarily known for its role as a neurotransmitter in the central nervous system (CNS). However, the functions of serotonin go beyond its role in the central nervous system: different peripheral tissues have the capacity to produce and/or use serotonin locally, forming systems called "micro-serotonergic" systems. Among the peripheral roles of serotonin, previous work by the Iron and Immunity team, INSERM U1016, Institut Cochin (Paris), was able to show that serotonin has a positive role on erythropoiesis and the survival of red blood cells, and the team's ongoing work suggests that serotonin also impacts iron metabolism. In humans and in mouse models, several studies have suggested a role for serotonin in pigmentation. In certain syndromic forms of albinism such as Hermansky Pudlak syndrome, platelet serotonin levels are reduced in connection with a decrease in dense platelet granules (delta granules): this characteristic is even part of the diagnostic criteria. Preliminary data from the Iron and Immunity team found: - Changes in serotonin levels in children with albinism compared to control patients, - Changes in hemoglobin level and mean corpuscular volume (MCV) in children with albinism (towards anemia and microcytosis), - Changes in the iron balance in children with albinism (towards iron deficiency). The hypothesis of this research is that peripheral serotonin plays a role in the clinical and biological manifestations of oculocutaneous albinism.
The oculocutaneous albinism is an autosomal recessive condition associated with mutations in 4 genes. In 20% of patients no mutation is identified. The optimization of genetic analysis methods and the search for new genes involved will help improve the diagnosis in these patients.
The purpose of the study is to evaluate and document physiologic and functional changes in visual performance and retinal function of patients diagnosed with albinism (a dopamine deficiency state) following a trial of oral Levodopa/carbidopa treatment.
Oculocutaneous albinism (OCA) is a term used to describe inherited forms of hypopigmentation associated with 1) variable levels of cutaneous hypopigmentation, ocular hypopigmentation, and visual deficits, and 2) involvement of both of the major developmental types of pigmented cells, i.e., melanocytes and retinal pigment epithelium. OCA that affects only usually-pigmented tissues is termed isolated OCA. There are currently seven albinism types (OCA-1 to OCA-7). With the exception of OCA-5, eash is associated with a specific gene and is inherited in an autosomal recessive manner OCA-5 is a proposed type of albinism associated with the chromosomal location 4q24. OCA-1 results from defects in the enzyme tyrosinase, which catalyzes the rate-limiting step in melanin synthesis. The precise functions of the remaining genes are not yet fully understood, but several may be associated with the regulation of pH in the subcellular organelle where melanin in manufactured-the melanosome. The majority of persons with OCA have two pathogenic mutations identified in a known OCA-causing gene, but a substantial minority to not. Ocular albinism (OA) is an X-linked disorder caused by mutations in the GPR143 gene. It affects the eye in a manner similar to OCA, but has minimal or no skin manifestations. In this protocol, we have four major goals: 1. To clinically and comprehensively characterize OCA types 1 - 7, and OA, with respect to the degree of hypopigmentation, genetic mutations, extent of ocular involvement, and longitudinal variation. 2. To use study participants cultured melanocytes to study pigment biology, variability in pigment formation related to genotype, and response to proposed treatments. Some of this work will be performed collaboratively. 3. To recruit study participants with hypopigmentation not due to known albinismcausing genes. 4. To evaluate methods of quantifying eye pigmentation, skin pigmentation and other clinical parameters that may be usable as outcome measures in future treatment studies. To achieve those goals, we will perform clinical evaluations of persons with OCA and OA at the NIH Clinical Center; obtain cultured cells, plasma, serum and urine for future studies; and, perform mutation analysis on known OCA and/or OA genes and search for other genes responsible for albinism. Routine admissions will last 3 - 4 days and occur every 2 - 3 years.
This study will examine whether five drugs (pravastatin, Losartan, Zileuton, N-acetylcysteine and erythromycin) used together can slow the course of pulmonary fibrosis (scarring of the lung tissue) in patients with Hermansky-Pudlak Syndrome (HPS). Patients with this disease have decreased skin color (albinism), bleeding problems, and sometimes colon problems. Two of the known types of Hermansky Pudlak syndrome, type 1 and type 4, are at high risk of pulmonary fibrosis between the ages of 30 and 50. Patients 18 to 70 years of age who have Hermansky-Pudlak Syndrome with a serious loss of lung function due to pulmonary fibrosis may be eligible for this study. Participants begin taking pravastatin on study day 2 and start a new drug every 3 days. Patients who experience no problems with the medicines return home and continue on the drugs for the next 2 years. They return to the NIH Clinical Center every 3 months for a medical history, physical examination, and blood, urine and lung function tests. CT and bone density scans are done every year. The study may continue for up to 3 years.
Hermansky-Pudlak Syndrome (HPS) is an inherited disease that results in decreased pigmentation (oculocutaneous albinism), bleeding problems due to a platelet abnormality (platelet storage pool defect), and storage of an abnormal fat-protein compound (lysosomal accumulation of ceroid lipofuscin). The disease can cause poor functioning of the lungs, intestine, kidneys, or heart. The most serious complication of the disease is pulmonary fibrosis and typically causes death in patients 40 - 50 years old. The disorder is common in Puerto Rico, where many of the clinical research studies on the disease have been conducted. Neither the full extent of the disease nor the basic cause of the disease is known. There is no known treatment for HPS. The drug pirfenidone blocks the biochemical process of inflammation and has been reported to slow or reverse pulmonary fibrosis in animal systems. In this study researchers will select up to 40 HPS patients diagnosed with pulmonary fibrosis. The patients will be randomly divided into 2 groups. The patients will not know if they are taking pirfenidone or a placebo "sugar pill". 1. Group one will be patients who will receive pirfenidone. 2. Group two will be patients who will receive a placebo "sugar pill" The major outcome measurement of the therapy will be a change in the lung function (forced vital capacity). The study will be stopped if one therapy proves to be more effective than the other.