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Characterization of Tissue-Specific Immune Responses to Bronchoscopic Instillation of Mycobacterial Antigens Into the Human Lung

Background: Tuberculosis (TB) is a lung disease. It is caused by inhaling a type of airborne bacterium. Tuberculin Purified Protein Derivative (PPD) is used to test for TB exposure. It is usually injected under a person s skin. In this study, it will be applied in the lung. Objective: To learn how the cells within the lung react (immune response) when exposed to PPD. Eligibility: Adults ages 18-64 who (1) have been exposed to TB but do not have active disease or symptoms or (2) have never been exposed to TB. Design: Participants will be screened with a medical history, physical exam, and blood tests. They will have a TB skin test. They will also have an electrocardiogram to examine heart rhythm. For this, sticky patches will be placed on their chest. Some screening tests will be repeated at study visits. Participants will have 3 FDG PET-CT scans. They will lie in a machine that creates pictures of the inside of their body. They will get a radioactive substance injected into their arm called 18FDG. It helps make the pictures. Participants will have 3 bronchoscopies. Their mouth and nasal airways will be numbed. They will get drugs to relax. A tube will be inserted through their nose or mouth into a lung. Fluid will be delivered into the lung and suctioned back out to collect cells. They will get PPD during the first bronchoscopy. Participation will last for about 30 days. Participants will visit the clinic up to 8 times. They will go home after each procedure. No hospital stays are needed....

Bethesda, MarylandStart: September 2021
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.

Bethesda, MarylandStart: September 2021
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.

Phoenix, ArizonaStart: September 2021
Effects of MDMA-like Substances in Healthy Subjects

The serotonin (5-HT) and oxytocin releaser and so-called "empathogen" 3,4-methylenedioxymethamphetamine (MDMA) acutely produces positive feelings, empathy, and trust. MDMA is used recreationally (ecstasy), as research tool to study 5-HT and oxytocin function, and is investigated for MDMA-assisted psychotherapy. MDMA is metabolized in part (10%) to the psychoactive metabolite 3,4-methylenedioxyamphetamine (MDA) which itself is also a recreational substance and has also been used to assist psychotherapy in the past. The present study aims to describe and directly compare for the first time the effects of MDMA and MDA in the same healthy volunteers and using modern psychological and psychometric tests. Additionally, although amphetamines including MDMA and MDA induce mainly positive subjective effects they may also produce negative subjective drug effects including anxiety in particular at the onset of the subjective response and the rapid onset of euphoria may increase the risk of abuse. Additionally, blood pressure may increase rapidly at drug onset. A possible solution to mitigate anxiety, abuse-related rapid euphoria increases and/or rapid blood pressure changes at onset consist of slowing the onset of the drug effect by using a slow-release formulation of MDMA. In the present study, the investigators will characterize the effects of lysine-MDMA and lysine-MDA and compare their effects with MDMA/MDA to test the concept of attenuated effects across both substances.

Start: February 2022