This study is sponsored by Children's Hospital of Philadelphia Department of Radiology. The purpose of this research is to study 18F-L-Fluoro-DOPA (F-DOPA), a tracer, which is used to take pictures of the pancreas. This imaging test is called an F-DOPA PET scan. The F-DOPA tracer is used to highlight areas of the pancreas that make too much insulin on the PET scan images. The test includes a CT scan (computerized tomography) done at the same time on the same machine, to help define exactly where the highlighted area is located within the pancreas and determine the location of blood vessels and other vital structures. Who can participate:

• Infants, children and adults with hyperinsulinemic hypoglycemia, diagnosed by a fasting test and/or response to glucagon stimulation
• Any age, from birth on
• Requiring surgery to remove part or all of the pancreas

The goal of the study extension is to see whether the incretin hormone GIP increases insulin secretion in individuals with CF and normal glucose tolerance compared to individuals without CF and normal glucose tolerance. This study includes 3 or 4 visits.

The purpose of the study is to evaluate blood sugar levels and beta-cell function in adolescents and adult with KATP hyperinsulinism whom did not undergo pancreatectomy. We will perform oral glucose tolerance tests, glucose potentiated arginine tests, and evaluate blood sugars in home environment by using continuous glucose monitoring for 10 days.

The purpose of this research study is to examine and understand the various mechanisms that contribute to CFRD and gain a better understanding of potential means to treat CFRD. Participation will include 2-3 visits, home monitoring, and will last about 2 years.

The goal of this study is to identify a safe dosing regimen for siplizumab in participants with type 1 diabetes. Siplizumab is a drug used to help treat recent onset type 1 diabetes mellitus (T1DM). This study is interested in participants aged 18-45 years with T1DM, who are within 18 months of receiving their diagnosis. Participants will be randomized (selected at random by the study team) to one of four possible treatment groups. All groups will receive weekly siplizumab doses administered subcutaneously (injected into the body through the skin) for a total of 12 weeks.

This study wants to know about the problems that Black or African American teenagers with type 1 diabetes (T1D) and their families face. It also wants to see how these problems affect their feelings, behavior, and how they get along with others. The study will find out how well they can handle T1D and adapt to it. It will also learn how good things like being strong, family, and where they live might help young people who have to deal with hard things. This includes how well they handle their feelings, behavior, relationships, and T1D care.

Our team has partnered with Moderna on a clinical trial for patients with glycogen storage disease type 1a (GSD1a). We would like to invite you to take part in a clinical trial for an mRNA investigational drug that could potentially correct the cause of GSD1a, by teaching your body to break down glycogen, correct low glucose, and avoid starch intake. The purpose of this trial is to see if a new investigational mRNA study drug, called mRNA-3745, is safe and if it works in the way researchers expect. mRNA technology uses messenger ribonucleic acid (mRNA), an instructional molecule that naturally occurs in the body and carries information to cells. In this case, we are studying if mRNA-3745 given through an IV infusion can instruct the body to make the protein that is missing in people with GSD1a.

mRNA-3725 is not approved by the FDA; the FDA has allowed us to provide this investigational medicine to patients enrolled in this phase 1/2 trial. Phase 1/2 clinical trials like this one aim to test the safety, side effects, and best dose of an investigational medication. In the phase 2 part, participants usually receive the highest dose of treatment discovered in the phase 1 part. This is the first study in which humans are administered this study drug.

If successful, mRNA-3745 would enable certain organs in the body to effectively break down glycogen and avoid low glucose levels and starch intake. If mRNA-3745 could correct the cause of GSD1a, it would help keep your glucose levels where they need to be all the time.

Participation in this clinical trial could last up to approximately two years, depending on which stage you enroll in and whether or not you decide to participate in the long-term follow-up period of the study. Some of the visits in this trial will require you to stay overnight at the hospital, and some of the visits will require you to visit the hospital or doctors office. Most of the visits in this clinical trial can be done at your home, where a home health nurse will perform the assessments needed.

All study-related procedures, travel, and compensation are provided.

NAD+ (nicotinamide adenine dinucleotide) is an important substance found in the body that plays a role in energy metabolism and overall health. The purpose of this research study is to test the performance of a new magnetic resonance imaging (MRI) technique (spectroscopy) to measure NAD+ metabolism in brain and skeletal muscle. MRI provides pictures of the inside of the body and information about chemicals the body makes.We are seeking to enroll males and females with Friedrichs Ataxia (FA) as well as healthy matched volunteers, 18 years of age and above. Pregnant females excluded for safety purposes.

The purpose of the study is to determine changes in lactate and creatine in calf muscle of healthy adult volunteers. Males and females of different ages (18 - 30 years, 45-55 years, and 70-80 years) will be asked to attend a single in-person study visit. Prior to the completing the MRI scan, the study team will review the health status of individuals.

The purpose of this research study is to learn more about Graves disease and PTC/Hypothyroidism, How it effects brain function and brain function changes after starting medical treatment.