Healthy

Researchers are looking for new weight loss medicines for people with higher body weight. The trial medicine, MK-4082, is different from similar weight loss medicines because people take it as a pill instead of an injection. Before giving a trial medicine to participants with a health condition, researchers first do trials in healthy participants to find a safe dose level (amount) of the trial medicine. The goal of this study is to learn what happens to MK-4082 in a person's body over time. Researchers will compare what happens to levels of MK-4082 in people's blood when it is taken without (Period 1) and with (Period 2) another medicine called diltiazem. Researchers also want to learn about the safety of MK-4082 taken with and without diltiazem and if people tolerate them.

The goal of this study is to learn what happens to a single dose of enlicitide over time in a healthy participant's body when the participant is given a single dose of MK-7262 and what happens to a single dose of MK-7262 over time in a healthy participant's body when the participant is given a single dose of enlicitide.

Background: About 5 million adults in the United States have age-related brain disorders. These include Alzheimer disease (AD), mild cognitive impairment (MCI), and other dementias. The number of people with these disorders will likely increase as the population ages and life span increases. Inflammation is thought to play a role in AD and MCI. Researchers want to know if an enzyme called PDE4B increases inflammation in people with AD or MCI. Objective: To test whether medical imaging using a new radiotracer (\[18F\]PF-06445974) can measure PDE4B in the brains of people with AD or MCI. Eligibility: People aged 50 years and older with AD or MCI. Healthy volunteers are also needed. Design: Participants will have up to 5 clinic visits with 3 imaging scans of the brain. They will have be screened. They will have a physical exam with blood tests. This will include tests of their heart and nerve function, including memory. Participants will have 2 positron emission tomography (PET) scans. One will use a standard radiotracer. The other will use the study radiotracer. They will receive each tracer through a tube attached to a needle inserted into a vein. During the scan with the study tracer, participants will have a second tube inserted into a vein in the wrist; this tube will be used to draw blood during the scan. Participants will lie on a bed that slides into a doughnut-shaped machine. These visits will take about 6 hours each. Participants will have 1 magnetic resonance imaging (MRI) scan. They will lie on a bed that slides into a cylinder. This visit will take up to 2 hours....

Background: Researchers have developed a new radioactive tracer (11C-ARMI). A tracer is a drug that attaches itself to other chemicals in the body and lights up so that the chemicals can be seen in imaging scans. The new tracer may be able to help them with many diseases, such as Alzheimer s disease and Parkinson s disease. Researchers want to test the new tracer in healthy people. Objective: To test a new tracer (11C-ARMI) during imaging scans of the brain and body in healthy people. Eligibility: Healthy people aged 18 years and older. They must have been screened under protocols 01-M-0254 or 17M0181. Design: All participants will have a positron emission tomography (PET)/computed tomography (CT) scan. Before the scan, they will have blood and urine tests and a test of their heart function. The tracer will be given through a tube attached to a needle inserted into a vein in the arm. They will lie on a padded bed that fits inside a doughnut-shaped machine; the machine uses x-rays to create images of the inside of the body. Some participants will have a PET/CT scan of their whole body. They will need only 1 visit. Some participants will have a PET/CT scan of only their brain. They will have up to 2 visits. On the second visit, they will have a magnetic resonance imaging (MRI) scan of the brain. For the MRI, they will lie on a table that slides into a cylinder. The MRI uses magnetic fields to create images of the inside of the body. Participants will receive a follow-up call to check on their well-being after their PET/CT scans.

In the present study, 120 healthy volunteers (HV) will be randomized to one of three ketamine-induced pharmacoBOLD (phBOLD) arms: low, medium, and high. Within each ketamine arm, participants will be randomized to 4 days of "study drug" \[TS-134 (1st 20 participants) or XT (remaining 100 participants)\] or placebo in a 5:3 ratio (25 study drug:15 placebo per arm). During the study, each participant will undergo a Screening Period (up to 31 days), a 4-day Treatment Period, and a total of two phBOLD sessions: a first session at Baseline and a second session on Day 4 of the Treatment Period, conducted at least 7 days apart, and a follow up visit.

The main objective of this trial is to investigate the effect of a moderate CYP 3A inducer bosentan on the pharmacokinetics of zongertinib.

Background: PDE4B is a protein in cells that helps turn off certain chemical signals after they ve done their job. It controls inflammation, immune responses, and some brain signaling. Measuring PDE4B levels in the body can help doctors manage a disease or know if a treatment is working. Researchers want to find out if a new tracer (a radioactive substance injected during imaging scans) can help them measure PDE4B in people more effectively. Objective: To test a new tracer (\[11C\]ZTP-1) during imaging scans of the brain and body in healthy people. Eligibility: Healthy people aged 18 and older. They must have been screened under protocols 01M-0254 or 17M0181. Design: Participants will have either 1 or 2 clinic visits. During their first visit, all participants will have a positron emission tomography (PET)/computed tomography (CT) scan. Prior to the scan, they will have blood and urine tests and a test of their heart function. The study tracer will be given through a tube attached to a needle inserted into a vein in the arm. They will lie on a padded bed that fits inside a doughnut-shaped machine; the machine uses x-rays to create images of the inside of the body. Some participants will have a PET/CT scan of their whole body. They will need only 1 visit. The visit will last up to about 8 hours. Some participants will have a PET/CT scan of only their brain. They will also have a magnetic resonance imaging (MRI) scan of the brain. They may need to return for a second visit for the MRI scan. Participants will receive a follow-up call to check on their well-being after their PET/CT scans.

Background: About 5 million adults in the United States have age-related brain disorders. These include Alzheimer disease (AD), mild cognitive impairment (MCI), and other dementias. The number of people with these disorders will likely increase as the population ages and life span increases. Inflammation is thought to play a role in AD and MCI. Researchers want to know if an enzyme called PDE4B increases inflammation in people with AD or MCI. Objective: To test whether medical imaging using a new radiotracer (\[18F\]PF-06445974) can measure PDE4B in the brains of people with AD or MCI. Eligibility: People aged 50 years and older with AD or MCI. Healthy volunteers are also needed. Design: Participants will have up to 5 clinic visits with 3 imaging scans of the brain. They will have be screened. They will have a physical exam with blood tests. This will include tests of their heart and nerve function, including memory. Participants will have 2 positron emission tomography (PET) scans. One will use a standard radiotracer. The other will use the study radiotracer. They will receive each tracer through a tube attached to a needle inserted into a vein. During the scan with the study tracer, participants will have a second tube inserted into a vein in the wrist; this tube will be used to draw blood during the scan. Participants will lie on a bed that slides into a doughnut-shaped machine. These visits will take about 6 hours each. Participants will have 1 magnetic resonance imaging (MRI) scan. They will lie on a bed that slides into a cylinder. This visit will take up to 2 hours....

The aim of the present study is to assess the impact of short-term forearm immobilization on forearm muscle glucose uptake and amino acid net balance and kinetics in individuals with T2D compared with a control group with normoglycaemia.

Skin health is influenced by the microbiome, lipids, oxidative stress, inflammation, and UV exposure. A 12-week trial with 48 women aged 45-65 will test if polyphenol-rich pulses improve skin health by affecting these factors. Using a white rice control diet, the study will measure skin parameters and analyze correlations with changes in lipids and microbiome, potentially proving the benefits of pulses.

Researchers are studying a medicine called MK-8527 to learn how it behaves in the body of healthy adults. The goal of this study is to learn about the effect of MK-8527 when it is taken with food or with other medicines. Researchers also want to learn about the safety of MK-8527 and if people tolerate it. Tolerate means participants will receive treatment in the trial unless they need to stop it due to health problems.

The goal of this project is to determine an individual's ability to generate active gut microbial metabolites called urolithins upon consumption of pomegranate dietary supplements. Recent publications have reported that urolithins are the major active metabolites responsible for the beneficial effects of eating pomegranates, berries, or walnuts. However, the production of urolithins from the parent compound ellagic acid (EA) is dependent upon the presence of certain bacteria in the human gut. In this trial, we propose to investigate variations in gut microbiota and their capacity to metabolize pomegranate dietary supplements (PDS) into active urolithins. We will measure the levels of urolithins in blood as well as inflammatory cytokines in plasma samples upon consumption of PDS.

This study aims to evaluate the effects of a dual Bifidobacterium longum probiotic formulation (dipro-O and dipro-X) on sleep quality, stress responses, and gut microbiota stability in healthy adults during short-term travel. Using a randomized, double-blind, placebo-controlled design, the study investigates whether probiotic supplementation can enhance sleep resilience, buffer stress, and modulate microbiome and physiological responses under travel-related environmental changes.

The objective of this trial is to evaluate the effectiveness of a mobile app-based motor skills intervention (DigiKids RCT) on motor competence, physical activity, and perceived motor competence compared with standard school practices in primary school children. In addition, the study will examine other factors such as child-specific and family-related factors that might influence the findings.

The goal of this study is to learn what happens to a single dose of enlicitide over time in a healthy participant's body when the participant is given a single dose of MK-7262 and what happens to a single dose of MK-7262 over time in a healthy participant's body when the participant is given a single dose of enlicitide.

The goal of this clinical investigation is to evaluate the performance of three neuromuscular electrical stimulation (NMES) foot pad programmes in healthy adults. It will also learn about how well the NMES programmes are tolerated. The main questions it aims to answer are: * Do two newly-developed NMES programmes ('P1' and 'PM7') increase lower limb blood flow more than the existing 'Medic' NMES programme during use? * How do the programmes compare in terms of user discomfort and muscle oxygenation during use? Researchers will compare the P1 and PM7 programmes with the existing Medic programme to determine whether the new programmes produce greater improvements in lower limb haemodynamics during device use. Participants will: * Attend four study visits at a single research site. * Complete 1 familiarisation visit and 3 testing visits, with 12 hours to 7 days between visits. * Use all three NMES programmes once in a randomised order. * Receive 30 minutes of NMES during each testing visit. * Undergo blood flow and muscle oxygenation measurements during each test. * Complete questionnaires about discomfort and their experience using the device.

The primary purpose of this study is to evaluate the safety and tolerability of QX-4533 following oral administration of single and multiple ascending doses in healthy participants.

Ketogenic diets are very low-carbohydrate diets that increase hepatic production of ketone bodies, which have several effects as substrates and signals. Ketogenic diets are used to manage some conditions (e.g., drug-resistant epilepsy), and their potential for managing many other conditions (e.g., cancer) is being actively explored. Indeed, the British Dietetic Association acknowledge the potential for ketogenic diets to improve glycaemic control to a greater extent than some other diets in people with type 2 diabetes. A lower fasting glucose is also relevant to future mortality in people without diabetes. Ketogenic diets are popular in the general population, with up to 15% of the UK following a low-carbohydrate diet. There is, therefore, great interest in ketogenic diets amongst people with and without health conditions. However, although the diet shows promising results in improving blood sugar levels, it has also shown to increase low-density lipoprotein-cholesterol (LDL-c) in some individuals, which has been linked to increased cardiovascular health risks. The aim of this project is to find the potential for personalised use of (or guidance to avoid) ketogenic diets for cardiovascular disease risk. To do that the investigators will ask participants to replicate 24 hours of a ketogenic diet and a control diet thrice each. This will allow the investigators to find variability between responses and have a better idea of individuals who could benefit (or not) from following the ketogenic diet.

The proposed study uses a mHealth application "app" to help parents teach their preschool-age child motor skill (FMS) activities in the home environment. This app guides families to participate in 10-min activity breaks, 7 days/week for 12 weeks and the app includes weekly instructional lessons, peer modeling videos, behavioral scaffolding, and structured activities. This study builds on prior work by assessing whether improvements in FMS generalize to cognitive domains, including executive function skills such as working memory, attention, and inhibitory control. By examining both motor and cognitive outcomes, the project will provide essential evidence on whether enhanced FMS uniquely contributes to cognitive development. Based on findings from the proposed study, there may be a need to develop additional modules that address diverse needs of children or that contribute to broader, multifaceted improvement in both motor competence and cognitive function. Findings will inform the potential of technology-based motor skill interventions to support broader aspects of child development in diverse populations, guiding future practice and policy in education, health, and early intervention.

Researchers are looking for new vaccines to prevent illnesses caused by a type of bacteria called Streptococcus pneumoniae. There are many different types of Streptococcus pneumoniae bacteria, called serotypes. Vaccines contain small parts of certain serotypes. These parts will not cause an infection but help the body create antibodies (proteins) to fight the bacteria. PREVNAR 20™ is a vaccine given to help to prevent disease from Streptococcus pneumoniae bacteria. Researchers designed a new vaccine, V118E, to help prevent disease from Streptococcus pneumoniae bacteria. The goal of this study is to learn how safe V118 formulation E is in Healthy Adults and how well people tolerate it.

This is a Phase 0 interventional, non-therapeutic study investigating the biodistribution and safety of \[18F\]-fluoromannitol as a radiotracer (a substance used to help detect disease or infection) in Positron Emission Tomography (PET) scans. The primary objective of this study is to generate safety data in healthy adult human volunteers. In the future, this tracer may help to determine if a medical problem is infectious in people who have Sickle Cell Disease, cancer or other conditions that impact the immune system, or with people who have joint implants. Primary Objective \- Generate safety data, biodistribution and perform human organ dosimetry for \[18F\]- fluoromannitol as a novel PET tracer. Participants will be recruited primarily from St. Jude Children's Research Hospital employees and SJLIFE participants, and from the broader Memphis community if needed.

The goal of this clinical trial is to learn the effects of technology enhancements when combined with basic education, goal-setting, and self-monitoring to increase physical activity among older adults living alone, experiencing subjective cognitive decline, and currently engaging minimal physical activity (60 minutes or less of moderate to vigorous physical activity). Further, we will examine key psychosocial mechanisms believed to contribute to successful promotion of physical activity, which include social support and stress resilience. The primary questions are to determine whether * the tech-enhanced condition lead to greater physical activity over time? * the tech-enhanced condition lead to social support and stress resilience over time? * social support and stress resilience mediate the relationship between the study condition and physical activity? All participants will engage in self-monitoring of physical activity, will receive weekly text reminders of their physical activity goals for the week, and will receive basic education about the importance of physical activity, social support, and stress resilience for cognitive, physical, and psychological health. Participants in the tech-enhanced condition will also receive access to a study-specific website and virtual coaching to reinforce the information presented. Researchers will then compare the tech-enhanced condition to the basic education condition to determine the benefits of technology to deliver the intervention materials in order to increase physical activity, social support, and stress resilience. Participants will: * Use a Garmin wearable device to monitor their physical activity * Be randomly assigned to a basic education condition or tech-enhanced condition * Set achievable goals for weekly physical activity, with incremental increases to achieve 7000 average daily steps by the end of the study * Respond to surveys to monitor their social support, stress resilience, quality of life, and depression. The sample has several risk factors for Alzheimer's disease and related dementias: low physical activity, social isolation risk via living alone, and subjective cognitive impairment. Therefore, a long-term goal includes the determination of the intervention's effectiveness at increasing physical activity, social support, and stress resilience to reduce risk for developing dementia.

The purpose of this study is to assess the impact of the Early Childhood Friendship Project (ECFP) on changes in aggression/peer victimization subtypes, prosocial behavior, and social and academic competence with a teacher-implemented (with coaching) version of the program. Further, investigators will examine whether changes in executive functioning, emotion regulation, and hostile attribution biases indirectly account for the program effects. Investigators will test if physiological reactivity (skin conductance and respiratory sinus arrhythmia) serves as moderators of intervention effects. Data will be collected from 600 children (30 randomly assigned preschool classrooms) diverse in socioeconomic status and race/ethnicity. Investigators will use multiple methods (school-based observations, direct academic assessments, child interviews, physiological reactivity using two tasks, observer, caregiver, and teacher reports) to assess the efficacy of the program, hypothesized mechanisms, and role of physiology as a moderator of intervention effects. The duration of the effects will be tested at both 4 month and 12-month follow-up and will thus demonstrate the impact the program has on children's school readiness and transition to kindergarten. It is expected that preschool children randomly assigned to the ECFP intervention relative to the control condition will show significant and moderate reductions in physical and relational aggression/victimization at post-test and follow-up; the ECFP intervention group will also show increases in prosocial behavior, social competence, and academic competence, relative to the control group at post-test and follow-up (4-months at the end of preschool and 12 months after transitioning to kindergarten). Additionally, it is hypothesized that changes in executive functioning, emotion regulation, and hostile attribution biases will mediate treatment effects from baseline to respective follow-ups. It is anticipated that these hypothesis will be moderated by gender such that effects will be stronger for girls relative to boys. Finally, it is hypothesized that physiological reactivity will act as a moderator of intervention effects and of the executive functioning, emotion regulation, and hostile attribution biases mechanisms.

The purpose of this trial is to learn about a trial medicine called MK-1403. Researchers designed MK-1403 to treat a type of heart and blood vessel disease called atherosclerotic cardiovascular disease (ASCVD). Before giving a trial medicine to people with a health condition, researchers first do clinical trials in healthy people. This trial will help researchers learn about the safety of MK-1403 and if participants tolerate it. Tolerate means participants receive the trial medicine and they do not need to stop taking it due to health problems. The trial will also measure what happens to MK 1403 in a healthy person's body over time.

The purpose of this study is to determine the effect of obesity on cardiovascular responses during various breathing maneuvers.