Healthy Paid Clinical Trials in Maryland

Objective: In this study we will develop and apply imaging techniques to perform the first three-dimensional (3-D) measurements of brain biomechanics during mild head movement in healthy human subjects. Biomechanics is the application of mechanics, or the physical principles in action when force is applied to an object, to the anatomical structure and/or function of organisms. Such techniques will be invaluable for building computational models of brain biomechanics, understanding variability of brain biomechanics across individual characteristics, such as age and sex, and determining brain sub-structures at risk for damage when movement of the head is accelerated, such as during a traumatic event. Study Population: Measurements will be performed on 90 healthy men and women aged 18-65. Design: We will build upon the model pioneered by our collaborator, Dr. Philip Bayly. The model places a human subject in a magnetic resonance (MR) scanner with one of two head support units that allows a specific range of motion. Each head support is latched such that it can be released by the subject, and results in either a rotation of the head of approximately 30 degrees or a flexion-extension of the head of approximately 4 degrees. Although both supports are weighted so that the motion is repeatable if the subject is relaxed, the subject can easily counteract the weight. The resulting acceleration/deceleration is small (in the range of normal activities, such as turning one's head during swimming) and has been validated and used in other human investigations of brain biomechanics. The subject repeats the motion multiple times during the MR scan under their own volition and desired pace to measure motion of the head and brain. Outcome measures: This project is a pilot study evaluating the potential of extracting three-dimensional estimates of brain deformation, such as strain measurements, using MR imaging. A primary outcome of this project will be a fast MR acquisition sequence for measuring 3-D brain deformation. The sequence will be evaluated by applying the protocol to human subjects, followed by preliminary quantification of the reproducibility and stability of deformation measurements. Read Less

The etiology of pulmonary fibrosis is unknown. Analyses of blood, genomic DNA, and specimens procured by bronchoscopy, lung biopsy, lung transplantation, clinically-indicated extra-pulmonary biopsies, or post-mortem examination from individuals with this disorder may contribute to our understanding of the pathogenic mechanisms of pulmonary fibrosis. The purpose of this protocol is to procure and analyze blood, genomic DNA, and specimens by bronchoscopy, lung biopsy, lung transplantation, extra-pulmonary biopsies, or post-mortem examination from subjects with pulmonary fibrosis. In addition, blood, genomic DNA, clinically-indicated extra-pulmonary biopsies, as well as bronchoscopy and post-mortem examination specimens may be procured and analyzed from relatives of subjects with hereditary forms of pulmonary fibrosis; blood, genomic DNA, and bronchoscopy specimens may be procured from healthy research volunteers.... Read Less

Background: When people have a stroke, they often have difficulty moving their arms and hands. Transcranial magnetic stimulation (TMS) can improve how well people with and without stroke can move their arms and hands. But the effects of TMS are minor, and it doesn t work for everyone. Researchers want to study how to time brain stimulation so that the effects are more consistent. Objective: To understand how the brain responds to transcranial magnetic stimulation so that treatments for people with stroke can be improved. Eligibility: Adults ages 18 and older who had a stroke at least 6 months ago Healthy volunteers ages 50 and older Design: Participants will have up to 5 visits. At visit 1, participants will be screened with medical history and physical exam. Participants with stroke will also have TMS and surface electromyography (sEMG). For TMS, a brief electrical current will pass through a wire coil on the scalp. Participants may hear a click and feel a pull. Muscles may twitch. Participants may be asked to do simple movements during TMS. For sEMG, small electrodes will be attached to the skin and muscle activity will be recorded. At visit 2, participants will have magnetic resonance imaging (MRI). They will lie on a table that slides into a metal cylinder in a strong magnetic field. They will get earplugs for the loud noise. At visit 3, participants will have TMS, sEMG, and electroencephalography (EEG). For EEG, small electrodes on the scalp will record brainwaves. Participants will sit still, watch a movie, or do TMS. Participants may be asked to have 2 extra visits to redo procedures. Read Less

Background: - Computed Tomography (CT) is a scan that makes detailed pictures of the body. It uses radiation to do that. In 2011, about 85.3 million CT scans were done in the United States. But there is growing concern about the health effects of radiation. There are new and different ways to make CT pictures that use less radiation. Researchers want to learn whether these new methods create images that are similar to images from a traditional CT. Objective: - To learn if new CT imaging methods with less radiation make images that are similar to traditional ways. Eligibility: - Adults 18 years of age and older who are scheduled for a CT of the chest, abdomen and pelvis with contrast. Design: Researchers will review participants medical records to see if they can be in this study. Participants may have blood drawn from an arm vein by a needle stick. The blood will be used to make sure they can be in this study and that it is safe for them to have contrast. During the participants CT scan appointment, one extra scan will be done using low radiation methods. During a CT scan, the participant lies on a table. A large x-ray machine takes pictures of the body. Read Less

More than 250 million courses of antibiotics are prescribed annually in the ambulatory care setting in the United States alone, including more than 40 million in children under 18 years of age. The perception that antibiotic use has minimal attendant adverse side effects contributes to the over-utilization of antibiotics in clinical circumstances when they are not strictly indicated. We have learned much about the human microbiome. The emerging view is of profound life-long bi-directional interactions between our microbiota and our cells. Perturbations in the microbiota affect metabolic, immune, and cognitive physiology in experimental animal models. When a person takes an antibiotic, the antibiotic diffuses via the blood into all body compartments, selecting for resistance. We propose to examine the effects of two commonly used antibiotics (the beta-lactam, amoxicillin and the macrolide azithromycin) on human microbial populations and on metabolic and immune physiology, studying healthy human volunteers in a randomized controlled clinical trial at the NIH Clinical Center. Our hypothesis is that in addition to acutely perturbing the human microbiome, these agents will have measurable metabolic and immunologic effects, with residual effects in the weeks that follow. To test this hypothesis, we will assess the effects of a brief therapeutic course of antibiotics on microbiome and metagenome composition. After an initial evaluation period, antibiotics will be given for 7 days or 5 days (depending on the antibiotic), and there will be a post-treatment evaluation. A control group will receive no drug intervention. Specimens will be obtained from multiple sites at each of 10 time points occurring before, during, and after antibiotic administration, and used for estimating bacterial and fungal composition and gene content. We will also assess the effects of the antibiotic course on markers of innate and adaptive immunity as well as markers of metabolic and hormonal physiology. A subgroup of subjects will be studied in the clinical center metabolic chamber to assess 24-hour energy expenditure and its components (sleeping, diet-induced, and activity energy expenditure), as well as macronutrient oxidation rates (carbohydrate, fat, and protein), during 3 of the 10 study visits. In addition to the primary data analyses, we will build a model that integrates the temporal data to begin to understand the complex intertwined physiology between microbiome and host. Read Less

Background: - Imaging tests, such as magnetic resonance imaging (MRI), can provide information about heart and blood vessels. The tests let doctors can see the amount of blood vessel narrowing and vessel wall thickness. This information may help diagnose and treat heart disease and other conditions that lead to heart attacks. Better MRI methods are needed to improve heart disease diagnosis, especially by avoiding the use of radiation. Researchers are testing new techniques to improve the quality of heart MRI, compared with more complex studies like catheterization or angiography. Objectives: - To compare heart MRI techniques with other tests used to diagnose heart disease. Eligibility: - People at least 18 years of age who either have or may have heart disease, or are healthy volunteers. Design: Participants will be screened with a physical exam, medical history, and blood tests. They will have an angiography to study the inside of blood vessels. This test is an x-ray study of the blood vessels. It will be done either separately or as part of a set of tests to diagnose possible heart disease. Participants will have at least one and up to five MRI scans. The scans will involve different methods of studying the heart and blood vessels. Participants may also have a computed tomography scan to confirm the findings of an MRI scan. No treatment will be provided as part of this protocol. Read Less

The purpose of this investigation is to develop improved magnetic resonance imaging (MRI) techniques and hardware for studying brain function. MRI is a diagnostic tool that provides information about brain chemistry and physiology. This study will evaluate new MRI methods for monitoring blood flow to regions of the brain in response to simple tasks. The MRI machine used in this study is more powerful than those in most hospitals, permitting a higher visual resolution. Normal healthy volunteers over 18 years old may be eligible for this study. Candidates will be screened with a medical history and questionnaire, and a neurological examination. Study participants will have a yearly MRI scan. For this procedure, the subject lies on a stretcher that is moved into a donut-shaped machine with a strong magnetic field. A lightweight circular or rectangular coil a device that improves the quality of the images may be placed on the head. The scan time varies from 20 minutes to 3 hours; most scans last between 45 and 90 minutes. During the scan, the subject may perform simple tasks, such as listening to tapes, tapping a finger, moving a hand, watching a screen, or smelling a fragrance. More complex tasks may require thinking about tones or pictures and responding to them by pressing buttons. Information from this study will be used to develop better imaging methods that will, in turn, permit a greater understanding of normal and abnormal brain behaviors. ... Read Less

This study will collect biological samples for use in research experiments aimed at better understanding the clinical features of certain diseases. The specimens may be used to evaluate the effectiveness of known therapies, refine treatment approaches, identify potential new therapies, and explore opportunities for disease prevention. The following individuals 2 years of age or older may be eligible for this study: Patients with a cancerous solid tumor or a cancerous or non-cancerous blood disorder who are being screened for or who are enrolled in a treatment study at the NIH Clinical Center HLA-compatible donor family members (18 years of age or older) of the above patients who are being evaluated for or are enrolled in an NIH study as a stem cell transplant donor Patients with a cancerous solid tumor or a cancerous or non-cancerous blood disorder or a bone marrow failure condition who cannot participate in an NIH treatment protocol or travel to the NIH Clinical Center and who are referred for participation through their home health care provider. Research samples will be collected from participants when blood is drawn or bone marrow, urine, or stool is collected, or tumor or other tissue is biopsied as part of their general medical care. Investigators may periodically request an additional sample of blood, stool, or urine. Participants who are 18 years of age or older may donate a large number of white blood cells through a procedure called leukapheresis. This procedure is not part of general medical care and would be done for research purposes only. For apheresis, a catheter (plastic tube) is placed in a vein in the subject's arm. Blood flows from the vein into a cell separator machine, where the white cells are separated from the red cells, platelets, and plasma by a spinning process. The white cells are removed and collected, and the rest of the blood is returned to the subject through a second tube placed in the other arm. ... Read Less

Background: - Changes in how a person s body burns energy or calories can affect their weight over time. The lowest level of energy the body needs to function is called basal metabolic rate. In the cold, we burn extra energy, even before we start to shiver. This is called non-shivering thermogenesis and it occurs in different types of tissue such as muscle and fat. Researchers want to learn more about this type of energy burning and how it is regulated. They hope this will help treat obesity in the future. Objectives: Sub-study 1: to better understand how non-shivering thermogenesis works. Sub-study 2: to measure the effects of anti-obesity drugs on basal metabolic rate. Sub-study 3: to better understand the effects of mirabegron, a beta-3 adrenergic receptor agonist, on brown fat activity. Eligibility: - Healthy, lean adult males ages 18 to 35. Design: Participants will be screened with medical history, physical exam, blood test, and EKG. For sub-studies 1 and 2: Participants will receive one X-ray scan. Each day, all participants will: <TAB>- Have height and weight measured, and have urine collected. Spend 4 hours in a temperature-controlled room with furniture, toilet area, phone, and computer. They will wear small non-invasive devices to monitor activity, heart rate, temperature, and shivering. <TAB>- Walk for 30 minutes. -For sub-study 3: Participants will receive one DXA scan and up to 4 PET/CT scans and 4 MRIs Each stay, all participants will: <TAB>- Have height and weight measured, and have urine collected. Spend 6 hours in a temperature-controlled room with furniture, toilet area, phone, and computer. They will wear small non-invasive devices to monitor activity, heart rate, temperature, and shivering. Participants will be compensated for their time and participation at the end of the study Read Less

Background: Most medications that treat depression take weeks or months to work. Researchers want to develop fast-acting treatments. One dose of ketamine has a rapid antidepressant effect. For most people, this lasts a week or less. Repeated doses of ketamine may help maintain this effect. Objective: Main Study: To study the effects of ketamine in treating depression. Ketamine Metabolites Substudy: To study how ketamine effects brain chemistry. To study how ketamine effects the brain. This is done by looking at metabolites, which are created when a drug is broken down. Eligibility: Main Study: People ages 18-65 with major depressive disorder and healthy volunteers Ketamine Metabolites Substudy: Healthy volunteers ages 18-65 Design: Main Study: Participants will be screened in another study, with: Medical and psychiatric history Psychiatric and physical exam Blood, urine, and heart tests Participants will be inpatients at NIH for 4 phases totaling 14-20 weeks. Phase I (2-7 weeks): Gradually stop current medications MRI: Participants lie and perform tasks in a machine that takes pictures of the body. Mood and thinking tests Blood and urine tests Sleep test: Monitors on the skin record brain waves, breathing, heart rate, and movement during sleep. Transcranial magnetic stimulation: A coil on the scalp gives an electrical current that affects brain activity. Stress tests: Electrodes on the skin measure reactions to loud noises or electric shocks. Phase I tests are repeated in Phases II and III and in the final visit. Phase II (4-5 weeks): 4 weekly IV infusions of ketamine or a placebo during an MRI or MEG. For the MEG, a cone over the head records brain activity. Phase III (optional): 8 infusions of ketamine over 4 weeks Phase IV (optional): Symptoms monitoring for 4 weeks Participants will have a final visit. They will be offered standard treatment at NIH for up to 2 months. Ketamine Metabolites Substudy: Participants will be screened in another study, with: Medical and psychiatric history Psychiatric and physical exam Blood, urine, and heart tests Participants will be inpatients at NIH for 4 days. Study Procedures: Mood and thinking tests Blood and urine tests 1 infusion of ketamine Spinal tap and spinal catheter: Used to get samples of cerebrospinal fluid (CSF). This is a fluid that moves around and within the brain and spinal cord. Studying CSF will help us learn how ketamine effects brain chemistry ... Read Less

Background: - National Institute on Aging researchers are looking at studies that require large numbers of white blood cells for lab use. Standard blood samples do not provide enough white blood cells for these studies. Researchers want to use cytapheresis to collect white blood cells from volunteer donors. This procedure can collect larger amounts of white blood cells and reduce the amount of fluid and other cells that are lost. Objectives: - To use cytapheresis to collect white blood cells for study. Eligibility: - Healthy blood donors at least 18 years of age. Design: Participants will be screened according to the usual blood donation procedures. Participants will provide white blood cells through cytapheresis. The blood cells will be collected in a machine that separates the white blood cells from the rest of the blood. The rest of the blood will be returned to the donor. Participants may have this type of donation every 56 days (six times per year). They will be asked to become a repeat donor. A donation schedule may be set up. Once a year, participants will have blood tests to continue to be eligible as a donor. Read Less

Background: - By the time diseases of the retina are detected, serious damage has often already been done. Researchers want to find better ways of viewing the retina. One way called adaptive optics may help detect problems earlier. Objectives: - To study if adaptive optics can help find better ways to diagnose, treat, and manage retinal diseases. Eligibility: People over age 12 with an eye disease. Healthy volunteers over age 12 with 20/20 vision or better. Design: Participants will be screened with medical history and eye exams. These may include dilating pupils and taking pictures of the eyes. Participants will have 1 or more study visits. They will have: Medical and eye history. Questions about their medications. Eye exam including pupil dilation. Adaptive optics imaging. After dilation, participants sit still while looking into an adaptive optics instrument. They look at specific places and images are taken of their retina. They may also have: More images. Perimetry. Participants look into a lens and press a button when they see a light. Color vision tests. Electroretinogram. Participants will get numbing eye drops and special contact lenses. A small metal electrode will be put on their forehead. They will look at flashing lights and try not to blink. Read Less