Clinical Trials

This is a single-blind, prospective randomized controlled study to determine if a combination of purgative agent, prokinetic agent, simethicone, and position will improve small bowel visualization, diagnostic yield, and completion rate of capsule endoscopy.

The investigators' prior research has focused on defining the changes in expression of nuclear encoded mitochondrial genes that predict changes in insulin sensitivity in skeletal muscle, with the goal of defining the molecular mechanisms underlying the connection between mitochondrial dysfunction and insulin resistance in skeletal muscle. The purpose of this study is to determine whether experimental lipid oversupply decreases mitochondrial respiratory function. We will use mitochondrial respiration studies in vitro and mass spectrometry and proteomics analysis to test the hypothesis that experimental lipid oversupply: 1. Decreases mitochondrial respiration in response to lipid fuels. 2. Reduces abundance of mitochondrial proteins. 3. Alters phosphorylation of proteins in the electron transport chain. Three groups of subjects will be studied: lean, healthy control subjects (n=12), obese non-diabetic subjects (n=12) and patients with type 2 Diabetes Mellitus (n=12) for a total of 36 subjects. Twenty subjects have completed the study at Arizona State University; the remaining 16 subjects will be accrued at the Mayo Clinic in Arizona. Subjects will come to the Mayo Clinic 2 times. On study Day 1 subjects will be screened with a medical history and physical exam, and a 75 g oral glucose tolerance test, measure body fat percentage, and an electrocardiogram (EKG). On Study Day 2, subjects will report to the clinic after an overnight fast. Female subjects will take a urine pregnancy test. A muscle biopsy will be performed to take a small sample from one thigh. A lipid infusion will be performed for 5 hours (60 ml/hr), with blood samples taken at 8 intervals during the infusion. At the end of the 5 hour period, a second muscle biopsy will be taken from the other thigh. The fat infusion will stop, subjects will be given lunch and allowed to leave the clinic.

This is a single-center, randomized control trial of a code status video as an educational tool in the intensive care unit.  Subjects are stratified by patient or surrogate and are randomized to either watch an educational video on code status or not watch the video.  They are then asked knowledge base questions regarding code status as well as questions pertaining to comfort regarding code status.  Participants randomized to watch the video are also asked questions related to acceptance of the video.

This research study is being done to determine levels of proteins that are normally present in the blood and urine of healthy individuals so as to compare to those levels in patients with heart disease.

Normal blood and urine will be analyzed for levels of proteins and cardiac peptides which are affected by heart disease in the elderly. We are trying to determine if there are normal age-related changes when heart disease is not involved.

This research study is designed to help us better understand how the body controls the secretion of adrenocorticotropic hormone (ACTH) in young men and women.

ACTH is a hormone (a chemical that circulates in the blood and influences a person's health) that is made in and released by the pituitary gland in the brain. ACTH increases the production of cortisol by the adrenal gland.

Cortisol is a hormone which allows the body to respond to stress. Thus, ACTH and cortisol are called stress hormones.

Their levels differ in men and women, but doctors do not know why. This study will test how testosterone (male sex hormone) in men and estrogen (female sex hormone) in women control the stress hormones.

This question is important, because sex hormones increase in puberty and decrease with aging.

Evidence suggests a relationship between sleep deprivation and cardiovascular disease. Voluntary sleep restriction is common, with 28% of the US adult population reports getting 6 or fewer hours of sleep per night, and those who do are 24% more likely to have cardiovascular disease and have twice the risk of hypertension. Insufficient sleep may conceivably be one of the most common, and most preventable, cardiovascular risk factors. The investigators wish to determine whether 9 nights of modest sleep restriction results in activation of cardiovascular disease mechanisms, thus potentially increasing the risk of cardiovascular disease. The investigators will combine our cardiovascular studies with state-of-the art sleep monitoring and neurocognitive tests to provide unambiguous data on the neurologic effects of sleep restriction. Together, the investigators findings will help explain whether the reduced sleep duration in the general population may be contributing to the current epidemic of cardiovascular disease, and suggest strategies to reduce this risk.

This protocol involves performance of a hyperinsulinemic euglycemic clamp with 2 muscle biopsies and an exercise study with a muscle biopsy.

Type 2 Diabetes and cardiovascular disease are closely linked. A common abnormality in both conditions is insulin resistance. The primary cause of insulin resistance in not known. A significant question is what dietary components contribute to the development of insulin resistance. Based on epidemiologic data, it seems that the type of dietary fat is a significant contributor to the development of insulin resistance. However, some researchers argue that the main determinant is total amount of fat, not the composition. This study is intended to determine if the main types of fat (saturated, monounsaturated and polyunsaturated) ingested over a short time can cause insulin resistance in lean, healthy people. It has been demonstrated that 6 hours of intravenous fat infused into lean, healthy subjects can result in insulin resistance, as well as blood pressure elevation and endothelial dysfunction. Whether this is so with oral fat is not known. The question is important because there is debate about whether the type of fat is as important as the quantity of fat in a person's daily diet. Settling this debate will enhance the ability of health care personnel to determine the optimal dietary recommendations. This study will make use of a high fat diet consisting of vegetable oils high in the 3 main fatty acids in plasma (palmitate, oleate and linoleate). Because large fat loads can cause intestinal discomfort, a feeding tube will be used to bypass the stomach. The 3 oils will be assigned randomly following a base line study with saline 2 weeks prior to the intervention. Our primary endpoint is insulin resistance, which will be measured by a euglycemic, hyperinsulinemic clamp. Secondary measures will include changes in blood pressure and in vascular reactivity as measured by ultrasound after brief occlusion of a forearm vessel. The changes will be compared to baseline and to the other 2 groups.

The investigators' prior research has focused on defining the changes in expression of nuclear encoded mitochondrial genes that predict changes in insulin sensitivity in skeletal muscle, with the goal of defining the molecular mechanisms underlying the connection between mitochondrial dysfunction and insulin resistance in skeletal muscle. Three groups of subjects will be studied: lean, healthy control subjects (n=12) obese non-diabetic subjects (n=12) and patients with type 2 Diabetes Mellitus (n=12) for a total of 36 subjects. Twenty subjects have completed the study at Arizona State University; the remaining 16 subjects will be accrued at the Mayo Clinic in Arizona. Subjects will come to the Mayo Clinic 4 times. On Study Day 1 Subjects will be screened with a medical history & physical and a 75 g oral glucose tolerance test to determine if they are eligible for the study. On Study Day 2, subjects will report to the clinic after an overnight fast, undergo a euglycemic clamp (using deuterated glucose) to determine insulin sensitivity, and in addition have a muscle biopsy (basal biopsy for comparison). On Study Day 3, subjects will report to the clinic after an overnight fast, and undergo a Volume Oxygen Maximum (VO_2 max) determination. On Study Day 4, subjects will report to the clinic after an overnight fast to perform an exercise bout with muscle biopsy 30 minutes after the end of exercise. This will be followed by an overnight fast, and an additional muscle biopsy at 24 hours post exercise.

Information will be collected, images will be taken.