Diabetes Clinical Trials

Several studies have reported that diabetic subjects have lower plasma vitamin C concentrations than non-diabetic subjects. Although urinary vitamin C loss in diabetic subjects was reported to be increased in two studies, these are difficult to interpret due to lack of controlled vitamin C intake, inadequate sampling, lack of control subjects, or methodology uncertainties in vitamin C assay and sample processing. Consequently, it is unclear whether diabetic subjects truly have both low plasma and high urine vitamin C concentrations. We propose that low plasma vitamin C concentrations in diabetic subjects are due in part to inappropriate renal loss of vitamin C in these subjects but not in healthy controls. We will study nondiabetic controls and cohorts with diabetes. Vitamin C concentrations in plasma, RBCs, and urine will be measured in outpatients. In those willing to be admitted to the Clinical Center, we will measure vitamin C pharmacokinetics to determine the relative bioavailability for vitamin C in individuals with and without abnormal urinary loss of vitamin C (or renal leak). Single nucleotide polymorphisms (SNPs) will be determined in genomic DNA responsible for the two proteins mediating sodium dependent vitamin C transport, SVCT1 and SVCT2. We will also explore mechanisms underlying abnormal urinary vitamin C loss.... Read Less

Despite the overwhelming focus on genetic and genomic causes of human disease over the past two decades, it has been estimated that genetics is currently known to explain only 20% and 40% of the etiology of common disease. Thus, it is becoming increasingly apparent that human disease is a consequence of both genetic susceptibility and environmental exposures. Importantly, while individuals cannot change their genetic composition, we do have the ability both personally and as a society, to influence our environment, promoting health and decreasing the risk of disease. The Personalized Environment and Genes Study (PEGS) aims to determine how the environment and gene-environment interactions can inform our understanding of human health and disease. As science has evolved, so too has the science of this project. This evolution was reflected in a change in the title of this project from the Environmental Polymorphisms Registry (EPR) to the Personalized Environment and Genes Study (PEGS) to more accurately reflect the science that can be conducted. PEGS is a unique resource because of the depth of environmental phenotyping which includes extensive information from exposome surveys, as well as whole genome sequencing on a significant number of participants in the cohort. While it is small relative to genomic cohorts, none of these have the extensive environmental data that is present in PEGS. In addition, other cohorts with deep environmental data lack the depth of genomic data that is present in PEGS. Importantly, PEGS has already provided important analytic advances that are of great interest to and can be confirmed in larger cohorts such as All of Us. The Personalized Environment and Genes Study (PEGS) aims to provide a resource for environmental health translational research by examining gene-environment interactions in health and disease. PEGS is an extension of two previous efforts where it began as a pilot study, the Environmental Polymorphisms Study (EPS; IRB# 02E9004) and was approved subsequently as a full protocol titled the Environmental Polymorphisms Registry (EPR) (IRB #04-E-N0053 and transitioned to its current ID# 04-E-0053). The EPR was envisioned as a phenotype-by-genotype registry of participants who had donated DNA samples, and who had agreed to be contacted for follow-up clinical translational studies based on their DNA genotypes. At the time, the only information available was a participant s age, sex, race, and ethnicity. Further phenotyping of a participant and/or any biospecimens obtained were investigated during a follow-up translational clinical study on participants recruited based on their genotype (hence phenotype-by-genotype) and the PEGS was the first recruit-by- genotype study at the NIH. Following a period focused on recruiting approximately 15,000 participants to enable genotyping of rare (approximately 1% minor allele frequency) single nucleotide polymorphisms (SNPs), the PEGS Consortium Project was undertaken in 2010- 2011 to examine, using the DNA of nearly 4,000 participants, approximately 700 SNPs in approximately 80 environmental response genes that work in concert with environmental exposures to elicit a phenotype. Several clinical follow-up studies, genotype-phenotype association studies, and publications have resulted from the PEGS Consortium Project. To expand phenotype information available to researchers, the Health and Exposure Questionnaire was administered between 2013-2014. In 2017, a more detailed Exposome Questionnaire which includes questions relating to the external and internal exposome was administered. This was an important resource through which to integrate exposures with genotype-phenotype association studies. Whole genome sequencing has now been performed on approximately 4700 participants who were reconsented for this purpose, as indicated above. Questionnaire data was fully adjudicated and combined in a robust and searchable database. With the increased power of the data available, the project was renamed as the Personalized Environment and Genes Study (PEGS) and rolled out in Sept. 2021. ... Read Less

It is unknown if obesity contributes to the development of heart disease in African American men and women. This study was created to determine whether there is a relationship between sex and body size and the incidence of heart disease in African American men and women. Researchers will attempt to associate obesity with the presence of heart disease risk factors. Risk factors that will be studied include; total body fat, body fat distribution, fat content of the blood (triglyceride concentration, low density lipoproteins \[LDL\], and high density lipoproteins \[HDL\]), how fast fat is removed from the blood, and how well insulin works in the body. Scientific studies have shown that obesity and increased levels of fat content in the blood are important risk factors for heart disease in Caucasian women. However, similar studies in African American women have failed to show the same correlation. In fact, it appears that African American women in all three body weight groupings, nonobese, overweight, and obese experience high death rates due to heart disease. In addition, prior research has shown that obese African American men tend to have elevated levels of fat in the blood while African American women have normal blood fat levels. Therefore, if high levels of triglycerides (fat found in the blood) are not seen in non-diabetic obese African American women, it cannot be considered a risk factor in this population. This suggests that studies conducted on Caucasian women may not provide insight into heart disease risk factors in African American women. The study will take 2000 healthy non-diabetic African American men and women (ages 18-70) and body mass index 3 subgroups; nonobese, overweight and obese. Diabetes undeniably increases the risk of heart disease. Therefore patients suffering from diabetes will not be included in the study. Candidates for the study will undergo a series of tests and examinations over 2 outpatient visits. Subjects will have body fat analyses, resting energy expenditure measurements, an EKG (electrocardiogram), and specific blood tests. Researchers believe this study will provide significant insight into the causes of obesity and heart disease in African Americans. Read Less

This study will conduct a two-arm randomized controlled trial to test the efficacy of a culturally tailored version of the NYU Caregiver Intervention (NYUCI) plus enhanced support (ES) through online chat groups (the NYUCI plus WeChat/Kakaotalk/other social media apps \[popular social media apps for individuals of Chinese or Korean descents\] peer support which we call the NYUCI-ES in reducing health risks for cardiometabolic disease among older Chinese and Korean American adults caring for relatives with ADRD. In collaboration with community organizations across the New York and northern New Jersey metropolitan area, we will enroll 300 caregivers of people with ADRD (150 Chinese and 150 Korean) in this study. Aim 1: Develop culturally adapted informational and educational materials about dementia and caregiving issues for social service providers of the intervention and for family caregivers. Aim 2: Test the hypothesis, H1: A counseling and support intervention (the NYUCI-ES) will significantly improve psychosocial factors such as depression, stress self-rated health and chronic disease management among Chinese and Korean-American ADRD caregivers and these changes will be mediated by improvement in social support. H1a: By the first (6- month) follow-up, the mediators (increases in social support, stress reaction) will improve significantly in the intervention group compared to baseline values and the control group. H1b: These improvements will be maintained, and lead to reduction in depressive symptoms, and improvement in self-reported health and chronic disease self-management by the 12-month follow-up compared to the control group. Aim 3: Test the hypothesis, H2: the NYUCI-ES will reduce biologic risk factors, including metabolic health (glycosylated hemoglobin) and inflammation (Oxidative stress, lipid metabolism, etc.) within 6 months of enrollment compared to baseline and a control group; these changes will be mediated through increases in social support and decreases in depressive symptoms and will be maintained at the 12-month follow-up. The public health significance of these findings will likely have an impact on health care policy for CGs from diverse underserved ethnic and cultural backgrounds, potentially reducing morbidity, and improving their quality of life. Read Less

This is a prospective, multi-center, two-arm, randomized trial to quantify the performance of the EchoMark®/EchoSure® System for AVF diagnostic ultrasound when used under a protocol of biweekly use for assessing fistula maturation and reducing time to Clinical Maturation. Read Less

This study seeks to correlate microbiome sequencing data with information provided by patients and their medical records. Read Less

The purpose of this research is to obtain blood samples before and after a bariatric procedure to better understand the reasons for glucose intolerance and insulin resistance (diabetes) in the obesity, and the reasons for improvement of diabetes after bariatric surgery Read Less

Study Overview: This interventional study aims to assess whether training healthcare professionals (HCPs) increases the number of continuous glucose monitor (CGM) prescriptions for patients with Type 2 Diabetes in a Federally Qualified Health Center serving a predominantly Hispanic/Latino population. Research Questions: Does HCP training enhance CGM prescription rates in a primary care setting? Does receiving a CGM prescription lead to improved Type 2 Diabetes control, as measured by Hemoglobin A1c levels? What barriers do patients face when prescribed and using CGMs? Given the significant impact of CGMs on diabetes management, this project seeks to improve CGM utilization among eligible patients through a focused intervention for HCPs and evaluate diabetes outcomes for those who do and do not receive a CGM. Methodology: HCPs and staff from three clinics within the same healthcare system will undergo a brief, in-person training on current clinical guidelines and insurance eligibility for CGMs. A booster session will follow about one month later to reinforce learning and address any prescribing challenges. Training efficacy will be evaluated by comparing CGM prescription rates before and after training using electronic health records. HCPs will complete pre- and post-training surveys to assess changes in knowledge, beliefs, and prescribing practices related to CGMs. Additionally, a small subset of prescribers will participate in interviews about their experiences with CGM prescriptions four months post-training. Patient Recruitment and Surveys: Patients with Type 2 Diabetes will be recruited for surveys at baseline, and at 3 and 6 months. These surveys will gather information on their diabetes management experience, levels of diabetes distress, and whether CGM discussions occurred with their primary care provider. Participants who received CGM prescriptions will share their experiences and any barriers encountered. A subset will also be invited for interviews to further explore their CGM experiences. Conclusion: This study seeks to fill a crucial gap in understanding how HCP training influences CGM prescription rates and the associated diabetes management outcomes, ultimately aiming to enhance diabetes care for a vulnerable population. Read Less

Aim 1: Characterize shared decision-making and unmet patient-caregiver dyads needs for patients with diabetes and Alzheimer's Disease and related dementias (ADRD) while using a continuous glucose monitoring (CGM) device. Aim 2: Develop an interactive tool to enhance shared decision-making for diabetes management. Read Less

Background: - Generalized lipodystrophy can cause high blood fat levels and resistance to insulin. This can lead to health problems including diabetes. Researchers have found that the drug metreleptin improves health in people with this disease. Objective: - To test the safety and effectiveness of metreleptin. Eligibility: * People ages 6 months and older with generalized lipodystrophy who: * have received metreleptin through NIH studies AND * cannot get it through approved or compassionate use mechanisms in their home country. Design: * Participants will come to NIH approximately every 6 months during year one, then every 1 2 years. Financial assistance may be available for travel within the U.S. * At visits, participants will get a supply of metreleptin to take home for daily injections. They will have: * plastic catheter placed in an arm vein. * blood tests, urine collection, and physical exam. * oral glucose tolerance test, drinking a sweet liquid. * ultrasound of the heart, liver, uterus, and ovaries. A gel and a probe are placed on the skin and pictures are taken of the organs. * echocardiogram, which takes pictures of the heart with sound waves. * Resting Metabolic Rate taken. A plastic hood is worn over the head while the oxygen they breathe is measured. * Participants will have up to 3 DEXA scan x-rays per year. * Participants may have: * annual bone x-rays. * liver biopsies every few years. A needle will be inserted into the liver to obtain a small piece. Participants will sign a separate consent for this. * Participants must be seen regularly by their local doctors and have blood tests at least every 3 6 months at home. Read Less

Background: Stem cells are found in body tissues. They can regenerate into more of the same cells or become other types of cell. Researchers want to use stem cells from taste buds to try to make cells that secrete insulin. Taste buds are found mostly on the tip and sides of the tongue. Researchers also want to study if the number of taste buds and stem cells decrease as people age. They will remove small pieces of tongue tissue (about the size of a pen tip). The taste buds will grow back. It is hoped that studying taste bud stem cells can lead to new diabetes treatments. Objectives: To see if stem cells from taste buds can be isolated in humans. Eligibility: Healthy adults at least 18 years old Design: Participants will be screened with: * Medical history * Physical exam * Blood and urine tests * Tongue photograph and mouth inspection. Food coloring will be applied to the tongue. Participants will have 1 study visit. They will not eat or drink anything 8 hours before. * They will give blood and urine samples. * They will have a tongue biopsy. Vital signs will be checked. The inside of the mouth will be examined. The tongue may be cleaned. The tongue will be numbed. Five small pieces of tissue will be taken with a small scissor. Any bleeding will be blotted with cotton and should stop in minutes. * Participants will be monitored for about 30 minutes. They will get a snack or meal. * They will be told how to take care of the tongue for the rest of the day. Participants will be called a week later to see how the ... 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