Clinical Research Directory

Effects of Urolithin A Supplementation on Glucose Metabolism in Healthy Adults 55 >= Years Old: A Randomized Triple-Masked Controlled Clinical Trial

Background: As people age, the cells in the pancreas that produce insulin begin to release less of this hormone, and levels of blood glucose (sugar) rise. This can lead to illnesses such as diabetes. Urolithin A (UA) is a natural nutritional supplement that may improve how the body controls blood glucose. Objective: To learn if UA improves levels of insulin and other hormones that help control blood glucose. Eligibility: People aged 55 years and older with a body mass index of 27 or higher. Design: Participants will have 6 clinic visits over 8 weeks. Participants will be screened. They will have a physical exam with blood and urine tests and a test of their heart function. UA gelcaps are taken by mouth every morning at home. Half of participants will take UA. The other half will take a placebo. The placebo looks like the study drug but does not contain any medicine. Participants will not know which they are taking. Participants will have tests during the study including: Oral glucose tolerance: Participants will drink a sweet liquid. Blood will be drawn at intervals over the next 3 hours. Continuous glucose monitor: A sensor with a needle that goes just under the skin will be placed on the upper arm. Participants will wear this sensor throughout the study. Exercise. Participants will walk on a treadmill while their heart rate, hearth rhythm, and blood pressure are monitored. They will walk in a hallway at normal and fast paces. Imaging scans of the thigh; scans of the brain are optional....

Effects of Meal Macronutrients on Postprandial Lipids

Background: Abnormal fats in the blood can lead to many problems, including heart disease. Researchers want to learn more about how eating meals with different levels of nutrients affects fats in the blood. Specifically, they want to study people with too much body fat, too little body fat, and a kidney problem called nephrotic syndrome. Objective: To learn more about how different types of foods affect fat levels in the blood. Eligibility: People aged 18 years or older with a health condition that affects how their body handles fats. Healthy volunteers are also needed. Design: Participants will have 2 overnight stays in the clinic within 6 months. At each visit, after staying overnight, they will eat a breakfast casserole. At 1 visit, breakfast will be a high-fat, low carbohydrate meal. At the other, it will be a high-carbohydrate, low-fat meal. Participants will have a tube inserted into a vein in their arm. They will have blood drawn via the tube 12 times in 8 hours: 2 times before they eat the breakfast and 10 times after. Participants will have other tests during their stays: * A resting metabolic test captures the air they exhale and measures how much energy they use at rest. * A dual energy X-ray absorptiometry (DXA) scan measures how much fat and muscle they have. * A Fibroscan is a special type of ultrasound of the liver. * A body surface scan uses lasers to measure the total area of the body. * A bioelectric impedance (BIS) exam measures how fast small electric currents move through their body. Participants may opt to have a third visit. At this visit, the breakfast will be high in protein....

Studies of Blood Flow to the Brain During Thought

The purpose of this study is to use brain imaging technology to measure changes in blood flow to areas in the brain as individuals perform intellectual tasks. This study will use functional magnetic resonance imaging (fMRI) to examine blood flow to areas of the brain as participants engage in tasks associated with visual perception, visual recognition, and memory.

Early Metabolic Effects of Dolutegravir or Tenofovir Alefenamide in Healthy Volunteers

Background: People with HIV take drugs to keep the amount of virus in their body low. One type of these drugs, called integrase strand transfer inhibitors (INSTIs), can cause weight gain over time. Weight gain can cause diabetes, heart disease, and other serious issues. Researchers want to understand how INSTIs cause weight changes. Objective: To see how a common INSTI, dolutegravir (DTG), affects how the body uses energy. DTG will be compared with a non-INSTI drug, tenofovir alafenamide (TAF). Eligibility: Healthy people aged 18 to 55. Design: Participants will be screened. They will have a physical exam and blood tests. They will have a nutritional assessment and tests of their heart function. Participants will have 2 inpatient stays at the clinic. Each stay will be for 11 nights, with a 3-week break between. Both DTG and TAF are gel caps swallowed once per day by mouth. Participants will take 1 drug for 8 days during each stay. Participants will have tests to see how their body uses energy: They will spend 23 continuous hours in a special room that measures how much oxygen they breathe in and how much carbon dioxide they breathe out. They will do this a total of 6 times. They will have a DEXA (dual-energy X-ray absorptiometry). DEXA is a kind of X-ray that measures body fat and bone density. They will lie on a table. Electrodes will be placed on their hands and feet to measure body fat and lean body mass. They will stand still on a platform for about 30 seconds. High-resolution laser cameras will scan their bodies.

Assessing the Impact of Perceptions of Unpredictability on Objective Measures of Food Consumption and Metabolism

Background: Many people in the United States are overweight or obese. This natural history study will look into how life events during childhood can impact eating behaviors and weight gain as adults. Objective: To explore how childhood experiences affect adult eating behaviors. Eligibility: Healthy people aged 18 to 60 years. Design: Participants will have 3 clinic visits. They will be screened with blood tests. They will answer questions about their alcohol and tobacco use. At the next visit, participants will undergo these activities: Parts of their body (such as waist, neck, and thighs) will be measured with a tape. They will have an imaging scan to find out how much body fat they have. They will start wearing a device like a wristwatch that measures their physical activity. They will wear this device for up to 10 days. They will wear a device on their upper arm or belly that measures blood glucose (sugar) levels. Participants will wear this for 7-10 days. They will answer questions about their education, childhood, and routines. They will receive a kit to collect a stool sample at home. At the last visit, participants will have these tests: Participants will relax and breathe normally while wearing a clear, plastic canopy that fits over their entire head. Blood samples will be taken before and after participants drink a sugary drink. Participants will be offered a large selection of foods for lunch. They will eat as much as they want. Then they will answer questions about how they feel about food and themselves.

Normal Values in Hearing and Balance Testing

Background: \- Researchers at the National Institutes of Health give many tests of hearing and balance. These tests can help detect problems that affect hearing or balance. It is important to know exactly how healthy people perform on each of these tests. This information will indicate when a test result is normal and when a test result shows a problem. Researchers also want to determine the best methods for each test. Objectives: \- To test different types of hearing and balance tests, and collect information on normal values for each test. Eligibility: \- Healthy volunteers between 5 and 80 years of age. Design: * This study will require a single visit to the National Institutes of Health Clinical Center. It will include both screening tests and study tests of hearing and balance. Sometimes, a second visit may be required if a test is designed to measure the same thing on 2 different days. Each visit will last between 2 and 5 hours, depending on the number of tests scheduled per visit. * Participants will have a physical exam and medical history. They will also have basic tests to check for normal hearing and balance. * Participants may have different hearing tests, including the following: * Auditory Evoked Potentials to study how the ears and brain handle sound information. * Auditory Processing Tests to study how a person processes complex sounds like speech in background noise. * Tests of middle ear and inner ear function. * Participants may have different balance and inner ear tests, including the following: * Balance test on a tilting platform. * Different tests to measure how well the eyes, ears, and brain work together to help maintain balance. * Treatment will not be needed as part of this study.

Safety and Tolerability Trial of Psilocybin in Healthy Older Adults

This study plans to learn more about the safety and tolerability of psychedelic administration (psilocybin) in healthy older adults ages 65-85.

Screening for Hematology Branch Protocols

This study allows the evaluation of subjects in order to determine their ability to safely participate in other active research studies. After subjects complete the screening process, they will be offered the opportunity to participate in an active research study, or if no appropriate studies are available information and recommendations will be provided for other treatment options....

Collection of Data and Samples From Healthy Donors for Use in Translational Research

Increased numbers of white blood cells called eosinophils can cause disease. To investigate this disease, researchers need blood, urine, sputum, stool, cerebrospinal fluid, skin and/or bone marrow samples to compare to samples from patients with this problem. Some of the samples will be used for genetic testing or future research. This study will last for about 10 years and will include a maximum of 50 paid volunteers ages 18 to 65.

Study of New Magnetic Resonance Imaging Methods of the Brain

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. ...

A Study to Assess Adverse Events, Tolerability, and Pharmacokinetics of Subcutaneous Injections of ABBV-295 in Healthy Adult Japanese Participants With Overweight or Obesity.

The purpose of this study is to assess the adverse events, tolerability, and Pharmacokinetics (PK) of subcutaneous injections of ABBV-295 in healthy adult Japanese participants with overweight or obesity.

Combining Motor Imagery and Tendon Vibration on the Effectiveness of Motor Imagery

Kinesthetic motor imagery (kMI) involves imagining the sensations of movement, activating brain regions similar to actual movement execution. It is widely used to maintain or restore motor functions, particularly in rehabilitation. Tendon vibration (TV), which stimulates proprioceptive receptors can also enhance corticospinal excitability and promote neuroplasticity. This project investigates the coupling of kMI and TV through three modalities: simultaneous application, TV application between kMI trials, or pre-application of TV to precondition the nervous system before kMI trials. The effectiveness and quality of kMI will be assessed by corticospinal excitability measurements using transcranial magnetic stimulation and EEG measures. Conducting this study in healthy participants will inform the development of optimized clinical interventions for immobilized or mobility-reduced patients.

Characterization of Diseases With Salivary Gland Involvement

Background: \- Salivary glands in and around the mouth and throat make saliva. Salivary gland disorders can affect a person s quality of life. Studying people who have a disease that affects their salivary gland(s) may teach researchers about the disorders and their genetics. Objectives: \- To study salivary gland diseases and disorders. To collect data and samples from people with salivary gland problems and their relatives. Eligibility: * People more than 4 years old who have or are suspected to have a disease involving salivary glands. * Their relatives more than 4 years old. * Healthy volunteers 18 years or older. Design: * Participants may be screened with: * Medical history * Physical exam * Blood and urine tests * General oral and dental history and exam * Saliva collection * Eye exam and test for dry eyes * Health questionnaires (adults) * Biopsy of some minor salivary glands. A small incision will be made on the inside of the lower lip and several tiny salivary glands will be removed. * Participants will have 2-3 visits. These may include: * Repeats of some screening tests * Ultrasounds of some glands. Researchers will put some gel on the face, then press on it with a smooth wand. * Adults may have other biopsies * A small catheter inserted into the opening of the parotid gland duct on the inside of the cheek. A saline solution (in a syringe) will fill the duct. * Swishing a saltwater solution in the mouth for 10 seconds and then spitting into a cup * Scrapings collected from teeth, tongue, and cheeks

Oral Bacteria and Immune System Problems Involved in Gum Disease (Periodontitis)

Background: \- Gum disease is a condition in which the tissue around the tooth root becomes swollen and infected. This condition can cause tooth loss if it is not treated. Who gets gum disease and how bad it will be depends on (1) the different bacteria in the mouth and (2) how the immune system of an individual handles these bacteria. Researchers want to look at the oral bacteria and genetic immune problems of different people to learn how these affect gum disease and other conditions of the mouth. Objectives: \- To study how immune system problems may lead to problems in the mouth, including gum disease. Eligibility: * Children and adults at least 7 years of age who have genetic problems with their immune system. * Healthy adults that have periodontal disease * Health adults that do not have periodontal disease Design: * This study will involve a screening visit and a study visit. * Participants will be screened with a medical history, blood work and a full oral and dental exam, including dental x-rays and photos. * The study visit will involve collection of blood, urine, and other samples, including saliva, plaque, and gum swabs. Any abnormal tissue will sampled for a biopsy. Additional oral and dental exams will be performed. Participants will also answer questions about any current medical or dental problems.

A Phase 1 Study to Assess the Effect of ABBV-722 on Ethinyl Estradiol and Levonorgestrel Drug Levels in Healthy Adult Female Participants

The objective of this study is to assess the effect of repeated doses of ABBV-722 on the single dose pharmacokinetics (PK) of ethinyl estradiol and levonorgestrel.

Impact of Exogenous Ketones on Breathing in Healthy Volunteers

Exogenous ketones (EK) are compounds that can increase the level of ketones in the body without needing to change what an individual eats. Although EK have been researched mainly in relation to energy and exercise, there haven't been many studies focusing specifically on how EKs affect breathing using well-established scientific methods. The investigators believe that EK may help improve breathing, which could be beneficial for situations like high altitudes, sleep apnea, and exercise. To explore how EK might influence breathing, the investigators are conducting a randomized, placebo-controlled crossover study with healthy volunteers.

A Phase 1 Study of the Safety and How the Body Processes ABBV-722 and Upadacitinib After Multiple Oral Doses in Healthy Adult Participants

This is a Phase 1 study to investigate safety and pharmacokinetics of ABBV-722 and Upadacitinib following multiple oral doses in healthy adult participants.

Safety Study of Intravenous Hydrogen-Oxygen Ultrafine Bubbles in Adults

The goal of this clinical trial is to learn whether hydrogen-oxygen ultrafine bubbles can be safely given through a vein (intravenous infusion) to adults. This is a first-in-human study, meaning this type of infusion has not been tested in people before. The study focuses on safety and does not aim to treat or prevent any disease. The main questions this study aims to answer are: 1) Can hydrogen-oxygen ultrafine bubbles be given safely without causing serious or unacceptable side effects? 2) What dose range can be given safely to adults for future research? About 40 adult participants, including healthy volunteers or people with mild, stable health conditions, will take part in the study. Each participant will receive two intravenous infusions, given one week apart. Some participants will receive a higher dose during the second infusion, depending on their assigned study group. Researchers will closely monitor participants before, during, and after each infusion. This includes checking vital signs, heart activity, and blood tests. The study will also collect exploratory laboratory measurements, such as markers related to oxygen levels and oxidative stress, to help guide the design of future studies. Participants will be followed for safety for about three weeks after starting the study. The information gained from this research will help determine whether hydrogen-oxygen ultrafine bubbles can be studied further in clinical research.

Development of Magnetic Resonance Spectroscopic Imaging Techniques for Imaging Metabolites in Human Brain and Muscle

Background: \- Magnetic resonance imaging (MRI) is a widely used scanning technique to obtain images of the human body and evaluate activity in the brain. A particular MRI method called magnetic resonance spectroscopy (MRS) can be used to study brain chemistry as well, which may help researchers who are studying new treatments for psychiatric illnesses. Researchers are interested in improving current MRI and MRS techniques, as well as developing new MRI and MRS techniques to view and measure brain chemicals and brain activity. Objectives: \- To implement, develop, and optimize brain chemistry imaging techniques using magnetic resonance imaging and magnetic resonance spectroscopy. Eligibility: \- Healthy individuals between 18 and 65 years of age. Design: * This study will involve a screening visit and a scanning visit at the National Institutes of Health Clinical Center. * Participants will be screened with a full medical and physical examination, blood and urine tests, and neurological testing. * During the second visit, participants will have an MRI scan of the brain. (Participants who have received an MRI within the past year will not need to have a second one; the images of the previous scan will be used for this study.) All participants will then have an MRS scan using the same scanning equipment.

Recruitment and Characterization of Healthy Research Volunteers for NIMH Intramural Studies

Objective: To screen and create a list of adult volunteers in good health for participation in research studies conducted at the National Institutes of Health (NIH) in Bethesda, Maryland. Develop a normative set of structural and functional brain MRI scans that are linked to healthy research volunteer characteristics. Maximize scientific impact of data from volunteers by broadly sharing with other researchers. Study Population: Adult males and females in general good health who are 18 years of age and older. Design: Adult individuals who are interested in participating in NIMH IRP clinical studies as a healthy research volunteer can directly visit or be directed to visit the study website where they will first consent electronically and then complete a set of online self-report measures. Items may include: demographic information, mental health symptoms, disability status, substance use patterns, handedness and clinical/family history. Individuals who are flagged based on predetermined responses to survey items will be further screened by a member of the study clinical team. If found to be ineligible for the study because of a clinically significant or unstable medical or mental health condition, these individuals will be referred back to the community and/or given information about NIMH clinical studies for which they may be eligible. Respondents with no flags or who pass through additional screening will be scheduled for an in-person assessment. During the outpatient appointment and after in-person informed consent, participants will receive a brief clinical interview to screen for current medical and mental conditions, and risk for self-harm. They will complete assessments of psychological, emotional, physiologic, biological and cognitive functioning. Participants will undergo a physical exam and be asked to provide blood and urine samples for routine clinical labs. Participants can separately consent for an optional baseline brain magnetic resonance imaging (MRI) scan and an optional magnetoencephalography (MEG) exam. All consent forms will explicitly inform participants that if enrolled in the study, their de-identified data will be broadly and publicly shared through NIH-approved data repositories. Participants in this recruitment and characterization study will then be placed on a list of healthy research volunteers from which other NIMH IRP studies may recruit according to the inclusion and exclusion criteria in their respective IRB-approved protocols. Outcome Measures: Outcome measures may include demographic data, mental and medical history and symptoms, results of psychological, emotional, physiologic, biological, and cognitive testing, physical exam and MRI findings....

Physiological and Psychological Profiles

The participation of women in high-impact sports such as rugby and basketball has been steadily increasing in Saudi Arabia. These sports are known for their physical demands and competitive nature, which have heightened the incidence of sports-related injuries. Understanding the predictive factors for these injuries is critical for developing preventive strategies, reducing long-term health consequences, and reducing healthcare burdens. Therefore, this study aims to identify the predictive effect of physiological factors (e.g., muscle strength, anaerobic power, oxygen consumption) and psychological factors (e.g., self-efficacy, resilience) on sports injuries among female athletes in Saudi Arabia, particularly focusing on those involved in rugby and basketball. A prospective cross-sectional design will be employed, involving a total of 30 female athletes aged 18-35 years actively participating in rugby and basketball. Data will be collected at the lifestyle research center through a series of physiological assessments, including maximal oxygen consumption, anaerobic power testing, isokinetic muscle strength testing, and psychological evaluations using validated questionnaires. The findings are expected to provide insights into the specific factors that increase injury risk among Saudi female athletes, offering targeted strategies for injury prevention. These strategies aim not only to minimize injuries but also to reduce associated healthcare costs, thereby supporting the sustainable growth of women's sports in Saudi Arabia. Ultimately, this study seeks to contribute to the broader objectives of Vision 2030 by promoting a vibrant sports culture and enhancing public health.

Variability In Mixed Meal Tests: Fixed Versus Adjusted to Energy Needs Caloric Dose

Background: Researchers use mixed meal tolerance tests (MMTTs) to look at how people s bodies respond to eating a meal. However, researchers do not agree on how to decide the number of calories to give in each meal. Some use fixed meals, which are the same size for everyone, and some use adjusted meals, based on the size of the person s body. Researchers want to know which MMTT is best to use for future research. Objective: To learn how fixed vs adjusted meals affect blood glucose levels in healthy people. Eligibility: Healthy people aged 18 years or older. Design: Participants will have 3 or 4 clinic visits of up to 8 hours in 8 weeks. Participants will have baseline tests: Their height, weight, and waist size will be measured. They will have an oral glucose tolerance test: A needle attached to a tube (IV) will be inserted into a vein in the arm. They will have a sugary drink. Blood samples will be taken from the tube at intervals up to 3 hours after the drink. They will have a body scan. Participants will have 2 MMTT visits. One will include a fixed meal and one will include an adjusted meal. They will have tests at both visits: Resting metabolic rate: A clear hood will be placed over the participant s head while they rest for 20 minutes. This will measure the oxygen they breathe in and out. MMTT. Participants will have 5 minutes to drink a liquid meal. Blood samples will be taken at intervals for the next 4 hours....

A Study to Assess How Intravenous and Subcutaneous Administrations of Risankizumab Moves Through the Body of Healthy Adult Participants

The purpose of this study is to compare how the drug moves through the body following risankizumab subcutaneous (SC) and risankizumab intravenous (IV) doses.

ENX-205 SAD/PET Study in Healthy Adults

This is a two-part study designed to evaluate the safety, tolerability, pharmacokinetics (PK), and receptor occupancy (RO) of ENX-205 in healthy adult participants in a double-blind placebo-controlled, single ascending dose (SAD) study (Part 1) and an open-label, single-dose, positron emission tomography (PET) study (Part 2).