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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.
The purpose of this study is to evaluate the impact of cryotherapy spray treatment for eradication of gastric antral vascular ectasia by measuring the change in hemoglobin levels and transfusion requirements in the first 6 months of cryotherapy treatment compared to the previous 6 months
Based on prior research, the investigators are interested in whether an intervention targeting gut health (supplemental fiber for 9 weeks total) will improve vascular health in individuals with obesity. Additionally, the investigators are interested in if this response differs based on whether individuals with obesity have very few heart disease risk factors or several heart disease risk factors.
Adverse childhood experiences (ACEs) are directly related to cardiovascular morbidity and mortality, and impaired vascular endothelial function (VEF) is an independent predictor of future cardiovascular disease (CVD) risk \[1, 2\]. Previous work from our lab (IRB 202010095) and others \[3\] demonstrates impaired VEF in young adults with prior exposure to ACEs even in the absence of clinical CVD risk factors. Sirtuin 1 (SIRT1) is a class III histone deacetylase (HDAC) that plays a role in regulating vascular homeostasis and reductions in SIRT1 are associated with age-related endothelial dysfunction \[4\]. We have shown that ACEs-related impairments in VEF are accompanied by reductions in SIRT1 \[5\]. However, the mechanisms by which ACE exposure promotes VEF remain unknown. The goal of this project is to establish proof of concept that alterations in vascular SIRT1 expression and activity mediate premature vascular aging in individuals with \>=4 ACEs compared to those with 0 ACEs and that, because NAD+ is an essential substrate for SIRT1, increasing NAD+ bioavailability will restore VEF in those with \>=4 ACEs. Thus, we will use a robust translational approach coupling in vivo and in vitro measures of endothelial function, inflammation, oxidative stress, and SIRT1 expression and activity in young adults with (n=30-35) versus without (n=30-35) ACE exposure in a cross-sectional study, and during a randomized controlled trial employing a novel 4-week nicotinamide riboside (NR) supplementation approach to increase SIRT1 activity by increasing cellular NAD+ in ACE+ (n=15/group) to accomplish the following specific aims: 1. Determine the mechanisms by which ACE exposure alters the regulation of VEF by SIRT1. We hypothesize that compared to those without ACEs (ACE-), ACE+ will have (H1a) elevated endothelial oxidative stress and inflammation, (H1b) accompanied by reduced endothelial SIRT1 expression and increased p66SHC expression and acetylation of p65 and p53, (H1c) in association with lower VEF. 2. Determine how targeting SIRT1 by increasing NAD+ bioavailability affects VEF in young adults with ACEs. We hypothesize that systemic NR supplementation will (H2a) augment cellular SIRT1 activity and (H2b) improve VEF in ACE+. \[1\] Felitti, V.J., Anda, R.F., Nordenberg, D., Williamson, D.F., Spitz, A.M., Edwards, V., Koss, M.P., \& Marks, J.S. (1998). Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: The adverse childhood experiences (ace) study. American Journal of Preventive Medicine, 14(4), 245-258. https://doi.org/10.1016/S0749-3797(98)00017-8. \[2\] Jenkins, N.D.M., \& Robinson, A.T. (2022). How do adverse childhood experiences get under the skin to promote cardiovascular disease? A focus on vascular health. Function (Oxf), 3(4), zqac032. PMC9279110. 10.1093/function/zqac032. \[3\] Rodriguez-Miguelez, P., Looney, J., Blackburn, M., Thomas, J., Pollock, J.S., \& Harris, R.A. (2022). The link between childhood adversity and cardiovascular disease risk: Role of cerebral and systemic vasculature. Function. 10.1093/function/zqac029. \[4\] Thompson, A. M., Wagner, R., \& Rzucidlo, E. M. (2014). Age-related loss of SirT1 expression results in dysregulated human vascular smooth muscle cell function. American Journal of Physiology-Heart and Circulatory Physiology, 307(4), H533-H541. \[5\] Jenkins, N.D.M., Rogers, E.M., Banks, N.F., Tomko, P.M., Sciarrillo, C.M., Emerson, S.R., Taylor, A., \& Teague, T.K. (2021). Childhood psychosocial stress is linked with impaired vascular endothelial function, lower sirt1, and oxidative stress in young adulthood. Am J Physiol Heart Circ Physiol, 321(3), H532-H541. PMC8461842. 10.1152/ajpheart.00123.2021
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). Investigators 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.
Stroke survivors have compromised vascular function which may contribute to secondary stroke risk, cardiovascular disease, and may limit their exercise tolerance. Preliminary data shows a single bout of ischemic conditioning or oral ingestion of an over-the-counter antioxidant supplement called MitoQ may improve vascular function and muscle activity in individuals post-stroke.
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.