1,800 Clinical Trials for Various Conditions
The aim of this study is to assess the strengths and weaknesses of training models that are accessible, reproducible, and geared toward new learners. Specifically, the investigators aim to compare the four following models: Japanese shirataki konjac noodle, "Dragon skin" silicone vessel, standard silicone vessel, and the "blue-blood" chicken thigh model. This information will be valuable in assessing the utility of implementing a Japanese shirataki konjac noodle model in beginner microsurgical courses for both local and global education and outreach.
This is a longitudinal study to determine the influence of the menopause transition on autonomic and vascular function. PI Keller-Ross has published data demonstrating that postmenopausal females have greater sympathetic neural reactivity during a stressor compared with age-matched males and younger females and males. A paucity of literature exists, however, on the role of the menopause transition in autonomic function because the majority of experimental studies on menopause physiology are cross-sectional and/or focused on older, postmenopausal females . The influence of age on HTN is robust, whereas the effects of menopause are still unclear. Preliminary data demonstrate a clear association between age and sympathetic activity in females; how the transition through menopause influences these relations, however, remains unknown. The study will enroll 80 midlife (45-55 years of age) females to measure longitudinally the trajectory of autonomic and vascular function during the transition through menopause. The study hypothesizes that through the menopause transition, an increase in sympathetic activity and an impaired baroreflex sensitivity and endothelial function will emerge.
The goal of this study is to better understand how the back part of the eye-called the retina and the choroid-changes during pregnancy. Specialized photos of the eye will be taken at three different timepoints: early in pregnancy (first or second trimester), late in pregnancy (third trimester), and after delivery. This imaging is non-invasive and does not require contact with the surface of the eye. The photos taken will allow assessment of specific parameters, like blood flow and the health of specialized cells that support vision. Understanding how the eyes change during pregnancy may help guide how retina specialists understanding of retinal disease during pregnancy and better inform pregnancy outcomes.
Otherwise healthy women who develop preeclampsia during pregnancy are more likely to develop and die of cardiovascular disease later in life. The reason why this occurs is unclear but may be related to impaired endothelial function and dysregulation of the angiotensin system that occurs during preeclampsia and persists postpartum, despite the remission of clinical symptoms. The purpose of this investigation is to determine the mechanisms contributing to this lasting blood vessel damage caused by reduced endothelial function in women who have had preeclampsia compared to women who had a healthy pregnancy. Identification of these mechanisms and treatment strategies may lead to better clinical management of cardiovascular disease risk in these women. The purpose of this study is to examine differences in the microvascular balance of angiotensin II receptors women who have had preeclampsia. This will help the investigators better understand the mechanisms of dysregulated angiotensin II receptors in formerly preeclamptic women, and how activation or inhibition of these receptors may restore microvascular function. In this study, the investigators use the blood vessels in the skin as a representative vascular bed for examining mechanisms of microvascular dysfunction in humans. Using a minimally invasive technique (intradermal microdialysis for the local delivery of pharmaceutical agents) the investigators examine the blood vessels in a dime-sized area of the skin.
The long-term objective of this research line is to identify and implement an effective and feasible intervention capable of preventing and/or reducing the burden of cardiometabolic and obesity-related diseases that affect Mississippians and others. The pursuit of this long-term objective will begin with achieving the specific aims proposed in this pilot project, which are to determine the effect of single sprint training for improving (1) systemic macro-vascular function, (2) local and systemic micro-vascular function, and (3) cardiorespiratory fitness. These aims will be achieved using a randomized controlled trial whereby 40 males and females will be randomized into an intervention group (n=20) or time-matched negative control group (n=20). The intervention group will perform a single maximal effort sprint on a cycle ergometer for twenty seconds 3 days/week for 4 weeks and the control group will be asked to maintain pre-intervention habits/behavior over 4 weeks. All outcome measures are non-invasive, and will be assessed pre-, mid-, and post-intervention, with the exception of cardiorespiratory fitness, which will be measured pre- and post-. To achieve aim 1, brachial artery flow-mediated dilation via ultrasonography and systolic and diastolic blood pressure via automated oscillometry will be measured on the arm. To achieve aim 2, post-occlusive reactive hyperemia via near-infrared spectroscopy and reactive hyperemia via ultrasound will be measured in the arm and leg, respectively. To achieve aim 3, pulmonary gas exchange will be measured during a graded exercise test on a cycle ergometer. All outcomes will be compared across time between conditions and sex with a three-way Bayesian Repeated Measures ANOVA using pre-values as covariates and an uninformed prior. 95% credible intervals will also be calculated to power future investigations using this intervention. If the intervention is found effective, future studies will be conducted to determine the efficacy of the intervention in larger groups and more clinical populations, and to determine the mechanisms mediating the adaptations. If ineffective, the knowledge gained will be used to develop future interventions.
The purpose of this clinical trial is to evaluate Transdermal Continuous Oxygen Therapy (TCOT) as an adjunct to surgical wound healing in subjects undergoing vascular surgery for lower extremity arterial occlusive disease. It is the intention of this study to administer oxygen using the TCOT approach to the surgical sites of subjects undergoing the surgery and to monitor the healing of the incision as well as infection rate. The hypothesis is that oxygen delivered transdermally to the surgical site in a continuous manner for up to 28 days will accelerate the healing process and reduce the infection rate compared to the Standard of Care.
The Researchers are studying whether a vascular boot warming program plus standard of care anticoagulation can be a safe and effective method to resolve Deep Vein Thrombosis (DVT) ±Pulmonary Embolism (PE) earlier and prevent development of post-thrombotic syndrome (PTS). Additionally, to learn whether a more detailed imaging of the affected lower extremities will provide a more accurate and reliable method to guide treatment for this condition.
This is a multi-center, multi-cohort, prospective, open-label study of VELOS for treatment of vascular skin disorders. The plan is to enroll up to 60 subjects from up to 3 centers in the US and worldwide. The purpose is to collect data from the use of VELOS.
The objective of this research is to determine the effects of anti-VEGF drugs (bevacizumab, ranibizumab or aflibercept) on aqueous humor dynamics (AHD) in patients with retinal vascular disease. The underlying hypothesis is that anti-VEGF drugs increase intraocular pressure (IOP) by increasing aqueous inflow, decreasing uveoscleral outflow or both. The specific aim is to evaluate the changes produced in AHD after 1 baseline and a subsequent 1 monthly injection of anti VEGF agents.
Obtaining peripheral vascular access in medical patients is a necessary procedure for many healthcare providers. Peripheral vascular access is traditionally performed using palpation or visual inspection to identify appropriate points of entry in the vasculature after which a needle and catheter are threaded through the skin and surround fascia into the vessel of interest. This procedure, one of the most common procedures in the medical field including both artery and vein access, is not 100% successfully attempted. Operator skill heavily influences peripheral vascular cannulation. (Frisch et al. 2013) However, certain patient populations have difficult peripheral vessels to identify by palpation or visual inspection and past operators would be forced to perform the procedure blind based on anatomical landmarks. Recently, to aid vascular identification and increase cannulation success, a number of alternative techniques for peripheral vascular access have been described including ultrasound-guided. Ultrasound-guided vascular access has been utilized in vascular access with improved success rate. However, even with ultrasound guidance the first attempt success rate of cannulation was only approximately 65%. A proposed failure of ultrasound guided peripheral vascular access is most likely due to failure to advance the catheter into the vessel even the vessel was successfully punctured. The investigators propose a specific technique and the positive "Target Sign" as a means to obtain almost 100% successful peripheral vascular access. The investigators plan to enroll 100 surgical patients in the above study and study procedures will not differ from what a patient in the operating room under the care of anesthesia faculty would receive. The above study is simply a way to identify the steps regarding a specific technique.
Insulin resistance (IR) is an important contributor to increased cardiovascular disease risk in type 1 diabetes (T1D). The purpose of this study is to measure the effect of metformin on insulin sensitivity, vascular function and compliance, and mitochondrial function in T1D. The long term goal is to identify novel non-glycemic approaches to managing cardiovascular disease risk in T1D. The results of this study may validate a novel approach to T1D treatment that could significantly improve current management of cardiovascular disease risk in this high risk population.
Diabetic complications are an important source of blindness and mortality among Veterans. Their occurrence is unpredictable because of the highly variable effect of factors such as weight, diet and exercise. Improved prediction of diabetes complications has the potential to improve the care for Veterans with diabetes, especially if this can be done without any extra effort for the Veterans or their caretakers. All Veterans with diabetes in VHA are required to undergo annual retinal photography to screen for current diabetic retinopathy. The investigators have recently developed an automated, precise, fast, novel tool for measuring retinal vessels in these images. Manual measurement of retinal vessels has shown that these can predict future -not current- development of hypertension and also diabetic retinopathy. If the investigators can confirm that their tool can flag those Veterans at increased risk for developing these diabetes complications, this will allow earlier intervention and prevention. Because the tool only uses the images that are being taken anyway, there is no extra effort for either the Veteran or VA staff.
Human Adipose Tissue is considered as a new source for Stromal Stem Cells and offers a large therapeutic potential for many rare and common diseases that impacts millions of patients worldwide. The Stromal Vascular Fraction (SVF) of Adipose Tissue is relatively easy to extract with minimally invasive procedures such as elective liposuction in large quantities and therefore may be a cost effective source for cellular therapies in a wide range of medical specialties. In this study we aim to demonstrate the efficacy of Antria Cell Preparation Process© in obtaining human adipose derived Stromal Vascular Fraction (SVF) by performing histology, various cell counts, multiple surface marker tests and measurement of the residual amount of digestive enzymes as a safety measure for human clinical trials.
The prevalence, incidence, and severity of atherosclerotic disease all markedly increase with age. Basic experimental and observational data demonstrate that aging magnifies the pathologic and clinical consequences of established risk factors and is the most potent individual risk factor for coronary atherosclerosis and for adverse outcomes following an ischemic event. These findings suggest that normal aging alters the vascular substrate so as to promote the development and progression of atherosclerosis. The age-associated changes in vascular structure and function include an increase in central vascular stiffness, intimal proliferation, and endothelial dysfunction. The major hypothesis is that the above alterations in vascular substrate (i.e. vascular age) are an important determinant of the age associated increased likelihood for the development and progression of coronary atherosclerotic disease. This program will non-invasively characterize vascular age and atherosclerotic burden in BLSA participants and individuals with successful aging, i.e. those with no or minimal evidence of coronary atherosclerotic disease, and those with premature, clinically evident coronary artery disease. It will repeat measures of vascular age and atherosclerotic burden three years after the first assessment. By examining the impact of vascular age on the initial extent and the progression of atherosclerotic burden over a two to three-year period, it will test the hypothesis that vascular age is an important determinant of the ageassociated increase in atherosclerotic disease....
The goal of this clinical trial is to characterize blood vessel function and oxidative stress (a harmful condition that damages cells and tissues) in emergency medical technicians (EMTs). The main questions it aims to answer are: 1. Does an overnight shift work in emergency medical technicians reduce blood vessel function and increase oxidative stress? 2. Can supplementing with antioxidants help reduce the negative effects of night shift work in emergency medical technicians? Researchers will compare antioxidants to a placebo (a look-alike substance that contains no drug) to see if antioxidants work in reducing the negative effects of night shift work in emergency medical technicians. Participants will: 1. Report to the lab two separate times following an overnight shift to assess blood vessel functioning and oxidative stress 3. Take an antioxidant supplement or placebo during each night of shift work.
As people get older, especially women, they often feel dizzy or even faint when they go from sitting or lying down to standing up. This happens because their blood pressure (BP) drops, which can lead to falls, heart problems, and even death in older adults. When BP changes, it affects how well the heart works and how it talks with blood vessels. However, little research has been done on how the heart and blood vessels talk during times of low BP. The crosstalk between the heart and blood vessels is important, as it allows enough blood and oxygen to reach the brain and other vital organs. Some research shows that as we get older, the crosstalk does not work as well. This can make it harder for blood to flow properly or put extra pressure on the heart and arteries. That's why we want to study how the heart and blood vessels talk during a laboratory-simulated situation of low BP in young and older men and women. In our study, participants will lie down with their lower body in a chamber that creates a vacuum around their legs. This safely mimics what happens when you stand up quickly. We can then measure heart function, the stress on arteries, and BP while your legs are in that vacuum. We'll use an ultrasound to check the heart and a finger cuff to measure BP. We'll also see if gripping something firmly can help protect from sudden drops in blood pressure. This study will help us understand more about a condition called orthostatic hypotension and might even suggest that handgrip exercise could prevent it. The main questions the current study aims to address are: * Does the cross-talk between the heart and vessels become more impaired with aging during laboratory-simulated conditions of low BP? * Do women have worse crosstalk between the heart and blood vessels during laboratory-simulated conditions of BP? * Does hand gripping protect against drops in BP during conditions of low BP? All participants will be asked to * Complete two laboratory conditions on two separate days with a randomized order (like flipping a coin): * Exposure to a lower body negative pressure (LBNP) chamber to safely simulate low BP (control) * Exposure to a lower body negative pressure (LBNP) while conducting hand-squeezingexercise (experimental). The investigators will examine how heart and blood vessel interactions, as well as blood pressure (BP) responses, differ in young and older adults of both sexes when exposed to a laboratory-simulated low BP condition (LBNP), both with and without hand squeezing exercise.
High-resistance, short-duration inspiratory muscle strength training (IMST) is a novel lifestyle intervention involving 30 inhalations against a resistive load which requires only \~5 min/day and is thus ideal for youth with T2D (Y-T2D). We seek to 1: assess changes in casual and 24-hr SBP, endothelial function, and arterial stiffness after 3 months of IMST vs. sham training in Y-T2D, 2: Define changes in eGFR andalbuminuria after 3 months of IMST vs. sham in Y-T2D, 3: Interrogate mechanisms of IMST by translational assessments of NO bioavailability, endothelial NO synthase (eNOS) activation, and ROS/oxidative stress, and determine the role of circulating factors.
It is a 12-week study. The participants will follow three different diets, and during each diet period, and the participants will wear our device, and blood samples will be collected.
This early phase I trial compares sodium fluoride F-18 (F-18 NaF) positron emission tomography (PET)/computed tomography (CT) to the standard of care imaging scan (and fludeoxyglucose F-18 \[F-18 FDG\] PET/CT) for assessing the effects radiation therapy has on the blood vessels in the neck in patients with head and neck cancers. For people with cancers in the head and neck, doctors often use radiation to target both the tumor and nearby glands. Radiation therapy to this region can affect the blood vessels in the neck that supply blood to the brain. F-18 NaF and F-18 FDG are contrast agents that can be used together with PET/CT imaging to visualize areas inside the body. A PET scan is a procedure in which a small amount of radioactive glucose (sugar) is injected into a vein, and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is taken up. A CT scan is a procedure that uses a computer linked to an x-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create 3-dimensional views of tissues and organs. Combining a PET scan with a CT scan can help make the image easier to interpret. PET/CT scans are hybrid scanners that combine both modalities into a single scan during the same examination. Imaging with F-18 NaF PET/CT may be as effective or more effective than the standard F-18 FDG PET/CT for assessing the effects radiation therapy has on blood vessels in the neck in patients with head and neck cancers.
The goal of the proposed study is to understand the reasons for the variability in aerobic exercise (AE) training benefits on the vasculature in middle-age and older (MA/O) adults, including differences between men and women. To achieve this goal, a mechanistic randomized controlled (RCT) will be conducted, in which adults are randomized to 12-weeks intervention of AE or no-exercise Control. Our overall hypothesis is that the exercise response variation in vascular benefits is related to age and sex differences in the biological changes underlying vascular aging and/or the molecular transducers (i.e., circulating molecules) that communicate and coordinate the effects of AE on the vasculature in the periphery and brain. Because this is a mechanistic trial, the overall goal is not a single health-related outcome. Rather, the goal is to advance our understanding of the molecular signals and pathways underlying the systemic and local effects of AE on vascular health that may explain the variability in AE responses with age and sex. This knowledge will allow for the development of personalized age- and sex-specific AE recommendations, and/or provide insights into molecular targets that can be manipulated to enhance and/or mimic exercise in non-responders or in persons unable to exercise.
The purpose of this observational research study is to study if patients with herpes zoster, also known as Shingles, have a higher risk of vascular dysfunction (problems with blood vessels, including stroke) and vascular dementia (problems with mental decline as a result of decreased blood flow to the brain) compared to patients without herpes zoster. Patients are evaluated based on the group they are assigned too: 1. Herpes Zoster (HZ) Group: individuals presenting with untreated herpes zoster. These participants will have 6 visits: * Day 1 = 1st day presenting to clinic with acute zoster * 7 days post zoster * 1 month after Day 1 * 3 months after Day 1 * 6 months after Day 1 * 12 months after Day 1 2. Control Group: individuals without herpes zoster o Day 1 (only 1 visit will be completed) This study does not have a study medication/device. Standard of care for all patients will be followed.
The goal of this observational study is to learn if the measures of tissue oxygenation from the MIMOSA Pro imaging device correlate to standard vascular assessment tools in patients who receiving a lower extremity vascular assessment. The main questions it aims to answer are: * Do the MIMOSA Pro tissue oxygenation measures correlate to Ankle-Brachial Index, Toe-Brachial Index, transcutaneous oximetry, and Doppler wave forms? * Do the MIMOSA Pro tissue oxygenation measures correlate with disease classifications for peripheral arterial disease, venous disease, and wound stage? * Is the MIMOSA Pro able to measure vascular status more often than other modalities? Participants will be asked to follow standard of care, and also allow for their legs to imaged by the MIMOSA Pro.
In this study, tocilizumab-aazg (TYENNE) will be administered to see whether tocilizumab-aazg is safe in patients with a burst brain aneurysm and if it may prevent strokes in patients with a burst brain aneurysm.
The objective of this proposal is to determine whether heightened negative affective responsivity (NA-R) to daily stressors is related to blunted nitric oxide (NO)-mediated endothelium-dependent dilation (EDD) in working age adults and the extent to which this association is impacted by major depressive disorder (MDD).
Several studies have shown that the efficacy of clopidogrel for secondary prevention of major adverse cardiovascular events (MACE), including acute coronary syndrome, depends on the polymorphism of the CYP2C19 gene. However, studies with large sample sizes and long-term follow-up are missing. Moreover, the impact of this polymorphism on the risk of major adverse limb events (MALE), particularly in patients with peripheral artery disease of the lower limb, is unexplored. Additionally, the impact of CYP2C19 gene polymorphism on clopidogrel effectiveness in preventing recurrent stroke in diverse populations is unknown since most of the data are from Asian ancestry populations. We hypothesize that patients with CYP2C19 gene loss of function alleles are at high risk of MACE and MALE compared to those without loss of function alleles at long-term follow-up. We propose to assess MACE and MALE in a large cohort of patients with available CYP2C19 genotypes treated at the University of Florida Health to evaluate the impact of CYP2C19 gene polymorphisms on the risk of new or recurrent events at long-term follow-up. Our specific aims are Aim 1) to determine the impact of CYP2C19 gene polymorphisms (loss of function alleles vs. non-loss of function alleles) on the risk of MACE (a composite of all-cause death, non-fatal MI, and non-fatal stroke) at long-term follow-up; Aim 2) to evaluate the impact of CYP2C19 gene polymorphisms (loss of function alleles vs. non-loss of function alleles) on the risk of MALE (a composite of limb amputations, chronic threatening limb ischemia, acute limb ischemia, and limb revascularization) at long-term follow-up; and Aim 3) to evaluate the impact of CYP2C19 gene polymorphisms (loss of function alleles vs. non-loss of function alleles) on the risk of cerebrovascular events (CVE, a composite of any stroke and transient ischemic attack) at long-term follow-up.
Women with HIV have an increased risk of having a myocardial infarction (heart attack) as compared to women without HIV. One of the mechanisms underlying the increased risk of myocardial infarction among women with HIV may involve reduced ability to increase blood flow through large and small coronary arteries at times when increased flow of oxygen-carrying blood is needed. We are conducting a study randomizing women with HIV and either diabetes, chronic kidney disease, or both to health education alone or to health education plus referral to see either an Endocrinologist or a Nephrologist in a subspecialty clinic for consideration of treatment with medication in a class known as sodium glucose transporter 2 (SGLT2) inhibitors. SGLT2 inhibitors are clinically approved for use in patients with diabetes or chronic kidney disease but have been shown to be underutilized in people with HIV. One of our key analytic aims will be to test if SGLT2 inhibitor therapy results in improved blood flow through the large and small coronary arteries among women with HIV and either diabetes, chronic kidney disease, or both but who have no history of myocardial infarction. A second aim will be to test if subspecialty clinic referral (with or without SGLT2 inhibitor therapy prescription) results in improved blood flow through the large and small coronary arteries among the same group.
The far-reaching negative health effects of the reduced physical activity (RPA) epidemic are often overlooked by the general population and health professionals. Short-term RPA induces cardiometabolic dysfunction, including impaired glucose control and vascular function, that may precede disease development. The impact of existing health status on RPA-induced cardiometabolic dysfunction and recovery of impaired glucose control following RPA is unexplored. Thus, the investigators' objectives are 1) to investigate the effect of existing health status (cardiorespiratory fitness and adiposity) on the recovery of impaired glucose control following a period of RPA and 2) to determine the role of vascular function as a mechanism of impaired glucose control. The investigators' final objective is to 3) expose undergraduate students to meritorious biomedical clinical research methods. The investigators have piloted the clinical research methods and analysis with undergraduate researcher associates and are well-prepared to complete this proposal. Preliminary data show that low cardiorespiratory fitness and/or high adiposity impair the recovery of glucose control following short-term RPA. Thus, the investigators aim to examine the interactive role of health status (cardiorespiratory fitness and adiposity) on the ability to recover impaired glucose control following short-term RPA. The investigators also seek to examine changes in vascular function as a mechanism of recovery of impaired glucose control following a return to normal PA. The investigators will recruit men and women with divergent health status (cardiorespiratory fitness and adiposity) to examine glucose control and vascular function during 7-d of normal PA, 7-d of RPA, and 7-d of resumption of normal RA. Continuous glucose monitoring and oral glucose tolerance tests will be performed to assess glucose control. Increases in vascular shear stress induced by passive leg movement and central arterial stiffness will be measured to assess vascular function.
The purpose of this study is to compare two strategies for treating adults with suspected large vessel occlusion stroke within 7 hours of symptom onset. Researchers will evaluate whether direct transfer to the neurointerventional angiography suite improves recovery and reduces disability compared to the conventional approach of first being evaluated in the emergency department. The study will also assess safety and other health outcomes to guide care for stroke patients.
Most of the time, body weight is evaluated by looking at the ratio of your weight to your height. This measurement is called body mass index or BMI. However, BMI does not account for what your body is actually made up of (e.g., body fat versus muscle), which may be more important for determining cardiovascular disease risk. The investigators aim to understand vascular health in females with a "healthy" BMI with differing amounts of body fat and muscle mass. We will have participants come to the lab for two different study visits. At one visit, participants will eat a meal high in fat, and at the other visit, participants will undergo a stress task.
Obesity and type 2 diabetes mellitus (T2DM) represent major public health concerns in the aging Hispanic community. Tirzepatide, a novel dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist recently approved for the treatment of T2DM and obesity has been shown to be effective at reducing weight, improving markers of T2DM control, and improving cardiovascular health. Utilization of tirzepatide in the Hispanic community has been on the rise since FDA approval was issued, however the effects of tirzepatide use on functional outcomes in older Hispanic adults with obesity are not well established. Recent studies show that weight loss caused by tirzepatide may be driven by substantial loss of lean muscle mass, which may contribute to weakness and frailty, particularly among older adults. The proposed pilot study aims to evaluate how treatment with tirzepatide for 6 months affects muscle mass and function among older Hispanic adults, and if changes in muscle mass are linked to changes in functional status over the same time period.