View clinical trials related to Primary Dysautonomias.
Filter by:Background: Sj(SqrRoot)(Delta)gren s Syndrome (SS) is an autoimmune disease that affects the glands that produce saliva and tears, causing dry eyes and dry mouth. Researchers do not know the exact cause of SS, but they believe that it may be caused by abnormalities in the autonomic nervous system (ANS) that stimulate these glands. Objectives: To better understand ANS function in patients with SS. To compare information about ANS function in healthy individuals and in patients with SS. Eligibility: Patients with Sj(SqrRoot)(Delta)gren s Syndrome who are 18 years of age and older, and who are not pregnant or breastfeeding. Participants will be asked to taper or discontinue the use of certain medications or dietary supplements before the ANS testing. Participants must be willing to discontinue the use of alcohol and tobacco 24 hours prior to testing. Design: The study will require one inpatient admission and/or outpatient visits to the NIH Clinical Center. The following tests and procedures will be performed: - Saliva, tear, and sweat production measurements to evaluate the function of glands. - Testing of changes to the cardiovascular system, including blood pressure and blood flow testing, and an electrocardiogram designed to evaluate hemodynamic changes controlled by the ANS. - Testing of changes to the gastrointestinal system, including a swallowing assessment study, barium swallow study, and gastric emptying study designed to evaluate gastrointestinal function controlled by the ANS. - Tests to evaluate the ANS function in response to certain drugs (edrophonium, glucagon and acetylcholine). - Self-reported questionnaire on ANS function and emotional/psychological well-being. Additional procedures and tests may include the following: - Blood samples. - Optional skin biopsy to study sweat glands and nerve supply of the skin.
An experimental drug called L-DOPS increases production in the body of a messenger chemical called norepinephrine. Cells in the brain that make norepinephrine are often gone in Parkinson disease. The exact consequences of this loss are unknown, but they may be related to symptoms such as fatigue, depression, or decreased attention that occur commonly in Parkinson disease. This study will explore effects of L-DOPS in conjunction with carbidopa and entacapone, which are drugs used to treat Parkinson disease. We wish to find out what the effects are of increasing norepinephrine production in the brain and whether carbidopa and entacapone augment those effects. Volunteers for this study must be at least 18 years of age and able to give consent to participate in the study. To participate in the study, volunteers must discontinue use of alcohol, tobacco, and certain herbal medicines or dietary supplements, and must also taper or discontinue certain kinds of medications that might interfere with the results of the study. Candidates will be screened with a medical history and physical exam. Participants will be admitted to the National Institutes of Health Clinical Center for two weeks of testing. The study will have three testing phases in a randomly chosen order for each participant: - Single dose of L-DOPS - Single dose of L-DOPS in conjunction with carbidopa - Single dose of L-DOPS in conjunction with entacapone Each phase will last two days, with a washout day between each phase in which no drugs will be given and no testing will be performed. In each phase, participants will undergo a series of tests and measurements, including blood pressure and electrocardiogram tests. Participants who are healthy volunteers will also have blood drawn and will undergo a lumbar puncture (also known as a spinal tap) to obtain spinal fluid for chemical tests.
After acute stroke, baroreflex sensitivity (BRS) is impaired. This impaired acute stage BRS has been reported to be predictive of worsen outcome years after stroke in general. However, it is not very clear if the impaired acute stroke BRS would actually persist months after the acute stage. It is also not clear that such change, if any, would correlate with the functional outcome or prognosis after stroke. The trial is to investigate the longitudinal time course of BRS after ischemic stroke up to the 6th month post stroke and to see if there is any correlation of the changes in BRS with the functional outcome parameters using NIHSS and mRS scores throughout this period.
Within the framework of a prospective double-blind and randomized study evaluating the efficacy of continuous intrathecal baclofen therapy (CIBT) on paroxysmal dysautonomia (main objective) and hypertonia, recovery and tolerance (secondary objectives) during the initial recovery phase of severe head injury, continuous intrathecal baclofen infusion will be delivered. The first week of study is double-blind: the first of two parallel groups receives CIBT and the second group receives placebo. The main outcome (number of neurovegetative episodes) is assessed at the end of first week. The second week of study is open labeled: active treatment is continued in the first group and the second group starts active CIBT treatment. The third week of study, treatment is stopped in both groups.
This study will conduct tests in patients with primary chronic autonomic failure (CAF) to learn more about these disorders, which include pure autonomic failure, multiple system atrophy, Parkinson's disease with autonomic failure, and autoimmune autonomic neuropathy. Healthy volunteers and patients with primary CAF 18 years of age or older may be eligible for this study. Participants undergo some of the following tests: - Blood studies, including arterial catheter insertion to measure blood pressure and collect arterial blood samples, blood flow studies using sensors applied to the skin and a pressure cuff around a limb, and blood draw for genetic studies. - Bladder motility: Ultrasound test of bladder function. - Electrocardiogram and heart ultrasound. - Responses to changes in temperature: Warm water and then room temperature water are passed through watertight pads applied to the back and front of the body and body temperatures are measured. - Gastrointestinal motility: Bowel sounds are recorded using a microphone placed on the abdomen. - Lower body negative pressure: The lower body is placed into an airtight barrel-like chamber. Some air is sucked out of the barrel, causing blood to pool in the legs, as occurs during standing. - Lumbar puncture: A needle is inserted in the space between the bones in the lower back to collect a small sample of cerebrospinal fluid. - Microdialysis to measures levels of chemicals in the body fluid of certain tissues. A solution is passed through a thin tube inserted into the skin. Chemicals in the body tissues enter the solution. The solution is collected and the chemical levels are measured. - PET scanning: A nuclear medicine test to produce images of body organs. For patients with urinary problems, a catheter is inserted into the bladder before starting the scan. - Pupillometry: The pupil of the eye is measured using a special camera in a light-controlled room. - QSART. A small amount of a brain chemical is applied to the skin with a tiny amount of electricity, and the sweat in a nearby patch of skin is measured. - Measurement of saliva production, using a cotton-like material placed between the teeth and gums to absorb saliva. - Skin electrical conduction test, using sensors on the skin to measure sweat production. - Skin and core temperature measurements using sensors on the skin and in the ear canal. - Speech and swallowing assessment for patients with speech and swallowing difficulties. - Stress echocardiogram: A catheter is placed in the subject's arm for sampling blood or giving a drug while the subject exercises. During the test, blood pressure, pulse rate, and EKG are continuously monitored.
This study is designed to use PET scans in order to measure activity of the sympathetic nervous system. The sympathetic nervous system is the portion of the nervous system that maintains a normal supply of blood and fuel to organs during stressful situations. PET scan or Positron Emission Tomography is an advanced form of an X-ray. It is used to detect radioactive substances in the body. During this study researchers plan to inject small amounts of the radioactive drug fluorodopamine into patients. Fluorodopamine is very similar to the chemicals found in the sympathetic nervous system. It can attach to sympathetic nerve endings and allow researchers to view them with the aid of a PET scan. One area of the body with many sympathetic nerve endings is the heart. After giving a dose of fluorodopamine, researchers will be able to visualize all of the sympathetic nerve endings involved in the activity of the heart. In addition, this diagnostic test will help researchers detect abnormalities of the nervous system of patient's hearts.
Brain and nerve cells communicate with each other by releasing and picking up chemicals called neurotransmitters. Norepinephrine is a neurotransmitter used by part of the nervous system activated during stress called the sympathetic nervous system. The sympathetic nervous system is involved with regulating blood pressure and pulse rate. Researchers believe the level norepinephrine in the blood can be used to measure activity of the sympathetic nervous system. This study is designed to answer important questions about rates of release of norepinephrine into the blood stream, removal of released norepinephrine, and the sympathetic nervous system response to stress. Researchers will attempt to measure levels of norepinephrine and activity of the sympathetic nervous system in patients with high blood pressure, normal patients with family histories of high blood pressure, patients taking drugs that can effect levels of norepinephrine, and patients with diseases or conditions directly affecting the sympathetic nervous system.
This study involves sampling blood from both normal volunteers and patients with diseases known or suspected to involve body chemicals called catecholamines. The blood will be used to establish normal values for plasma levels of catecholamines and related neurochemicals; to test for abnormal neurochemical patterns in patients; and to establish a "bank" of DNA from normal volunteers and from patients to be used in future studies about possible alterations of catecholamine-related genes. Study participants will report to NIH after fasting overnight except for water or noncaloric, noncaffeinated beverages. They must not have taken Tylenol for at least 5 days. Blood will then be drawn. DNA will be extracted and stored in the freezer for future studies.