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229 active trials for Healthy Volunteers

Stereophotogrammetry of the Torso in Healthy Individuals and Patients With Scoliosis, Chest Wall Deformations, or Obesity

Background: - Stereophotogrammetry (SP) uses four sets of digital cameras to generate a three-dimensional computer image. Unlike other types of evaluations which require radiation, SP only uses computer images to learn more about physical deformities such as scoliosis or about the placement of fat on the body. To refine the SP process, researchers are interested in collecting images and body data from individuals with skeletal structural problems such as scoliosis or chest wall deformities, individuals who are overweight or obese, and healthy volunteers. Objectives: - To use stereophotogrammetry to study different individual body types and refine existing imaging techniques. Eligibility: - Individuals at least 2 years of age who have spine, rib, or chest wall deformities; are overweight or obese (body mass index greater than 25); or are healthy volunteers. Design: Participants will be screened with a physical examination and medical history. The physical examination will include measurements of range of motion and joint mobility, torso width and length, and other observational data. Healthy volunteers and participants in the obesity group will also have bioelectric spectroscopy (bioimpedance), which uses an additional machine to measure how fat is spread in different parts of the body. After the physical examination has been completed, participants will have SP photographs taken. Participants will be asked to remove all clothing from the torso, stand with arms raised at the center of four cameras, and remain still while several images are taken. A complete image takes less than 1 second. Participants with spine or rib deformities, or who are in the obesity group, may also volunteer to return for followup SP imaging, once a year for 5 years, to study progress over time....

Start: June 2011
Food Intake Response to Short-Term Modifications of Metabolism in Humans

One reason people gain weight is eating more calories from food than what they need for energy over 24 hours. Metabolism is the amount of energy a person uses over 24 hours. Researchers want to study the relationship between changes in metabolism and how much a person eats. Objectives: To see how much food a person eats when the body's temperature is cooled. To study how changes in metabolism may alter the amount of food a person eats. Eligibility: Healthy people ages 18-55. Design: Participants will stay at NIH for 20 days. During the first 4 days, participants will have: Medical exam Electrocardiogram Blood and urine tests. One blood test includes drinking a sugar solution. DXA body composition scan Questions about foods they like, physical activity, and personal behavior Exercise test on a stationary bicycle Participants will spend 24-hour periods in a metabolic chamber. The chamber will be at normal room temperature or cooler. Some times, participants will eat a diet that matches their daily needs. Other times, they can eat as much as they wish from a vending machine. Participants will have blood and urine collected. Participants will swallow an ingestible wireless sensor and wear a small data recorder device. On the second to last day, participants will stay in the metabolic chamber but only consume water and non-caffeinated sugar-free beverages. Participants will come back for 1-day visits at six months and one year from the first admission. They will have blood and urine tests, and a DXA scan. They will answer questions on physical activity and food habits.

Start: April 2017
Children s Growth and Behavior Study

Background: - Studies show that many factors affect children s eating behavior and health. These include sleep, mood, thinking skills, and genetics. Studying children over time may identify children at higher risk for eating-related health concerns. Objective: - To understand how genes and environment influence eating behavior and health over time. Eligibility: - Children ages 8 17 in good general health. Design: Screening visit 1: Medical history, physical exam, body measurements, and questions. 14 days: Participants will wear a wrist monitor and answer smartphone prompts about eating and mood. They may give a stool sample. Screening visit 2: Body measurements. Saliva, urine, and blood samples. Heart tests. Meals provided (after fasting overnight). Questionnaires and interview. Behavior, thinking, and exercise tests. X-ray of left wrist and full body.<TAB> Some parents may have medical history, physical exam, and questions at screening visits. They may answer questions at the yearly visits. Participants will have up to 6 yearly visits. They will give a urine sample and body measurements, and repeat the X-rays. They will have questions and behavior and thinking tasks. They may give stool samples. Visits will range from 3 to 8 hours. Participants may choose to participate in other studies: Stress and Hormones, 1 visit: While resting, participants will give saliva samples and have their heart monitored. Then they will do math. They will repeat the resting part, then do a computer task. Brain Imaging, 2 visits: Twice, participants will perform tasks with a magnetic cone on their head then answer questions. Once, they will have an MRI, lying still in a scanner with a coil on their head. Sleep, 2 visits: Participants will have food provided, answer questions and do tasks. Participants will be compensated for the time and inconvenience involved with completing study procedures.

Start: April 2015
Neurobiology of Suicide

Background: There are no good treatments for people considering suicide. Researchers want to study suicide with questions, blood tests, brain imaging, and sleep studies. They hope to better understand suicide, so they can help suicidal people. Objective: To understand what happens in the brain when someone has thought about or attempted suicide. Eligibility: Group 1: Adults ages 18 70 who have thought about or attempted suicide recently Group 2: Adults ages 18 70 who have thought about or attempted suicide in the past Group 3: Adults ages 18 70 who have depression or anxiety, but have never thought about suicide Group 4: Healthy volunteers the same ages. Design: Participants will be screened in another protocol. Adults who have recently thought about or attempted suicide must be referred by a doctor. They may do up to 3 phases of this study. Groups 2, 3 and 4 will do only Phase 1 and will not get ketamine. Phase 1: 1 week in hospital. Participants will have: Physical exam. Questions about thoughts and feelings. Thinking and memory tests and simple tasks. Blood and urine tests. Two MRI scans. Participants will lie on a table that slides into a metal cylinder that takes pictures. They will have a coil over their head and earplugs and do a computer task. Sleep test. Disks and bands will be placed on the body to monitor it during sleep. Magnetic detectors on their head while they perform tasks. A wrist monitor for activity and sleep. Lumbar puncture (optional). A needle will collect fluid from the back. Shock experiments (optional). Participants will observe pictures and sounds and feel a small shock on the hand. Phase 2: 4 days in hospital. A thin plastic tube will be placed in each arm, one for blood draws, the other to get the drug ketamine once. Participants will repeat most of the Phase 1 tests. Phase 3: up to 4 more ketamine doses over 2 weeks. Participants will have follow-up calls or visits at 6 months and then maybe yearly for 5 years.

Start: December 2015
Effects of Sucralose on Drug Absorption and Metabolism (The SweetMeds Study)

Background: Artificial sweeteners like sucralose are found in many foods and drinks. Sucralose might affect hormones and cause health changes. Objective: To see if sucralose changes how medicines are absorbed and processed, how hormones are secreted, gut bacteria, and how fat cells are metabolized. Eligibility: People ages 18-60 who: Are black or Hispanic Weigh more than 110 pounds Have a body mass index of 25-40 Do not have a condition that requires drug treatment Design: Participants will be screened with: Medical history Physical exam Blood, heart, and urine tests Participants must not eat or drink anything with artificial sweeteners throughout the study. Over 7 days, Participants will answer questions, and give daily urine samples and 1 stool sample. Participants will repeat these throughout the study. Overnight Visit 1: participants will fast starting the night before. They will get breakfast at the visit. The visit includes: An IV will be placed in the arm. Participants will get 2 tablets of medicines. Blood will be drawn several times over 24 hours. A piece of fat tissue may be taken from the abdomen (biopsy). Participants will have a sweet drink. Blood samples will be taken over 2 hours. Then participants will be randomly assigned to take either a sucralose capsule or placebo. They will take it twice a day for 2 weeks. They will complete two 24-hour food diaries. Overnight Visit 2 repeats Visit 1 except the biopsy. Then participants will take the capsules for another 2 weeks. Overnight Visit 3 repeats Visit 1. Participants may be contacted by phone within 4 weeks after they finish....

Start: April 2018
Impact on Anxiety and Motivation of COVID-19 and Predictors of Individual Responses

Background: Researchers think that people s mental health and behavior will be very affected by the steps taken to slow the spread of COVID-19, such as social distancing. Also, the threat of disease and death, to people and their loved ones, can cause much stress. Researchers want to learn more about these stressors and how they are affecting people. Objective: To study the relationship of affective, cognitive, and behavioral responses to stressors related to COVID-19 with neuroimaging and behavioral data collected before COVID-19. Eligibility: English-speaking adults age 18 and older Design: This online study will include both new participants and those who have taken part in past National Institute of Mental Health studies. All will complete the same surveys and tasks. Participants will give their name and email address. They will get a username and password. The file that links their username to their personal data will be kept secure. Participants will complete a set of surveys about the following: Sociodemographic data, such age, race, and income Education and work status Mental and medical illness and treatment Family medical history Mood COVID-19 experience Anxiety Substance and alcohol use Attention control Other mental health related topics. Participants will complete a finger-tapping task. For this, they will press a key a certain number of times in a limited period. They will get to practice the task. After the task, they will complete a survey about it. It will take about 1 hour to complete the surveys and the task. About 8 months later, participants will be contacted to repeat the surveys and task. Compensation is provided.

Start: June 2021
Genetic and Epigenetic Signatures of Translational Aging Laboratory Testing (GESTALT)

Background: - Biomarkers are substances in people s blood and tissues. They help researchers understand diseases and signs of aging. Scientists want to do more research on biomarkers to find ways to improve quality of life in old age. Objective: - To learn more about biomarkers and their relationship to aging. Eligibility: - Adults at least 20 years old who weigh at least 110 pounds and have a body mass index below 30. They must agree that their genetic samples can be collected, studied, and stored. Design: Participants will be screened with medical history, physical exam, and blood and urine tests. They will have heart tests and nurse will assess their veins. They will fill out a questionnaire. Participants will have a 2-day baseline visit. Then they will return every 2 years for up to 10 years. These follow-up visits will repeat the baseline visit: Repeat of screening procedures. Physical performance tests like balance and walking tests. Leg and grip strength tests. Health and mental state questions. Memory and problem solving tests. Cytapheresis. Blood will be removed through a needle in the vein of one arm and run through a machine. The blood will be returned through a needle in a vein of the other arm. Visits may also include: Magnetic resonance imaging scans. Participants will lie on a table that slides in and out of a machine that takes pictures. Diabetes test. After fasting, participants will drink a sweet drink and give blood. Breathing and walking tests. Wearing a device that record physical activity. Scan of the abdomen and the right leg. A small amount of muscle tissue and/or skin removed.

Start: April 2015
Brain Dopamine Function in Human Obesity

Background: Dopamine is a natural chemical in the brain that may influence eating behavior and physical activity. Researchers want to measure the brain s dopamine activity and understand how it differs in people with obesity. Objective: To better understand how brain function, particularly dopamine activity, relates to body weight and eating behavior. Individuals may be able to participate if they: Have a BMI of at least 18.5 kg/m2 Are weight-stable and generally healthy Are between ages 18-45 years Have normal blood pressure Are not using illegal drugs (based on urine drug screen) Are not following a special diet Do not have metal implants Design: Participants will be screened with: Medical history Physical exam Questionnaires and an interview to see if it is safe to have a PET/MRI scan Fasting blood and urine tests Participants will eat a special diet given to them for the 5 days before their inpatient visit. Participants will have a 5-day inpatient visit. Some days include blood and urine tests. Each day includes surveys and tests to measure habits and likes/dis-likes. A sample schedule may be: Day 1: Participants will wear a monitor that uses a needle below the skin to measure glucose. Their body fat will be measured with low-dose x-rays Day 2: Participants will have a PET scan. They will lie on a table that slides in and out of a donut-shaped scanner. They will be injected with a small amount of a radioactive substance and wear a cap on their head. Day 3: Participants will have an MRI. They will lie on a table that slides in and out of a scanner. Day 4: Participants will have another PET scan. This time, they will drink a milk shake during a break from the scanner. Then, they will go back inside the scanner for the end of their scan. Day 5: Participants will wear a hood for up to 40 minutes to measure their breathing. They will also drink special water and collect samples of their urine to measure the rate they burn energy. For 12 months after the visit, participants will track their weight and physical activity daily using a special scale and activity monitor. A few times over the year, the study team will send participants special activity monitors to use for 7 days at a time. Participants will have an in-person 1-day follow-up visit. This includes most tests except for PET scanning....

Start: September 2018
Developing Biomarkers of Dietary Intake: Dose Dependent Measurement of Sugar Intake

Background: Diet is one of the most modifiable behaviors affecting health. But diet assessment measures that are based on self-report can be inaccurate. Researchers want better ways to address the role of diet in chronic disease. They want to see if stable isotopes can be used to better assess what people eat. Objective: To see if stable isotopes can help scientists identify things people eat. Eligibility: Healthy adults ages 18 to 65 Design: Participants will be screened with a medical history and physical exam. They will have blood and urine tests. These tests will be repeated during the study. Participants will stay in the inpatient unit of the NIH in Phoenix, Arizona, for 13 weeks. For 7 days, participants will eat a diet prepared by the NIH kitchen. They will get balanced meals that are 50% carbohydrates, 20% protein, and 30% fat. Then participants will be randomly placed on one of 3 diets containing different percentages of carbohydrates from soda. Participants height and weight will be measured. The amount of fat and muscle in their body will be measured by body scans that are similar to x-rays. Participants will have oral glucose tolerance tests. They will consume a sugar drink and then give blood samples over 3 hours. Participants will give hair and stool samples. Participants will complete a diet questionnaire. It assesses their food intake over 24 hours. Participants will complete behavioral questionnaires and computer performance tests. Participants will have fat biopsies taken from their stomach and thigh. Participants will have three 24-hour stays in a metabolic chamber. It is used to measure metabolism.

Start: June 2021
A Research Study Investigating Mim8 in People With Haemophilia A

This study consists of 2 parts. Part 1 looks at the safety and tolerability when the study medicine Mim8 is given to healthy subjects for the first time. The obtained results will help to perform a second part of the study with patients who suffer from a bleeding disorder called haemophilia A. Haemophilia A is an inherited condition caused by a lack of a protein called factor VIII. Mim8 works in the body for a longer time than most other products used by patients with haemophilia A. Mim8 is designed for once weekly or once monthly administration. In Part 1, participants will be injected only once with either Mim8 or a "dummy" medicine (placebo) under the tummy skin - which one will be decided by chance. In this study, Mim8 will be used for the first time in humans. Mim8 is a new medicine and cannot be prescribed by doctors in any country. Mim8 belongs to a group of medicines called antibodies. Mim8 is designed to take over the function of the missing factor VIII in haemophilia A patients. Part 1 of the study will last for up to 20 weeks. Participants will attend a screening visit, followed by a 12-day in-house visit where they will have to stay in the study unit. This is followed by 10 ambulatory visits with the study doctor throughout the remaining part of the study. Assessments will include several blood tests and electrocardiograms (ECGs). In part 2 of the study, people with haemophilia A - with or without inhibitors - will be given injections with a thin needle in the skin of their stomach, either weekly or monthly. Part 2 of the study will last for 120 weeks.

Start: January 2020
Exploring the Effects of Corticosteroids on the Human Hippocampus

Chronic corticosteroid (CS) exposure is associated with changes in memory and the hippocampus in both humans and in animal models. The hippocampus has a high concentration of glucocorticoid receptors (GCRs), and the pre-clinical literature demonstrates shortening of apical dendrites in the CA3 region of the hippocampus and decreased neurogenesis in the dentate gyrus (DG) following CS administration. In humans, both stress and CS exposure are associated with a decline in declarative memory performance (a process mediated by the hippocampus). Impairment in declarative memory and hippocampal atrophy are reported in patients with excessive CS release due to Cushing's disease, and, by our group, in patients receiving prescription CS therapy. These findings have important implications for patients with mood disorders, as a large subset of people with major depressive disorder (MDD) show evidence of HPA axis activation, elevated cortisol and, importantly, resistance to the effects of CSs on both the HPA axis and on declarative memory. Thus, resistance to corticosteroids appears to be a consequence of MDD. this study will examine changes in declarative memory, as well as use state-of-the-art high-resolution multimodal neuroimaging, including structural and functional (i.e., task-based and resting state) MRI, in both men and women healthy controls, and, as an exploratory aim, a depressed group, given 3-day exposures to hydrocortisone (160 mg/day) or placebo. The study will translate preclinical findings to humans, provide valuable data on possible sex differences in the response to cortisol and, for the first time, identify specific hippocampal subfields (e.g., CA3/DG) in humans that are most sensitive to acute CS effects. Using resting state fMRI data and whole brain connectomics using graph theoretical approaches, we will determine the effects of cortisol exposure on functional brain networks. Furthermore, this will be the first study to use neuroimaging to compare the brain's response to CSs in people with depression vs. controls, and determine whether depressed people demonstrate glucocorticoid resistance within the hippocampus. We hypothesize that hippocampal response to acute CSs will be greatest in the CA3/DG subfield, greater in women than in men, and that depressed people will show a blunted hippocampal response to CSs compared to controls. A multidisciplinary research team with extensive experience in CS effects on the brain and hippocampal subfield neuroimaging, and a prior history of research collaboration, will conduct the project.

Start: October 2019
Samples From Human Subjects to Facilitate Basic, Translational and Clinical Research

Background: This study is designed to provide samples to help us study the genes your blood cells are making as well as the proteins, sugars, fats, vitamins and other metabolites found in your blood or urine. Blood samples may also be collected to make special cells. These are called induced pluripotent stem cells or iPSCs. Pluripotent stem cells are cells that can be converted into any type of cell. Researchers want to study in the lab iPSCs that are derived from blood samples. Objective: To collect samples to help study genes, proteins, sugars, fats, vitamins, and other metabolites found in blood or urine. Eligibility: Healthy volunteers and patients ages 18 and older Design: First-time research study participants at NIH will have an initial visit for this study that should last no more than 1 hour. All other visits should last 20 30 minutes. Participants will undergo a limited history and physical exam. Participants may have routine blood and urine tests. If participants are giving a blood sample, they must have a hemoglobin level checked in the past 12 months to make sure it is safe for them to give a blood sample for research. Participants may have a venous blood collection. They may do this at several visits. They will lie on a recliner or couch or sit in a chair. A needle will be placed into a vein in the hand or arm, using sterile techniques. Blood will be withdrawn into multiple syringes or tubes. Participants may be asked to provide urine in an appropriate container...

Start: September 2017