Physiology Commons^™

Longitudinal Analysis Of Arterial Blood Pressure And Heart Rate Response To Acute Behavioral Stress In Rats With Type 1 Diabetes Mellitus And In Age-Matched Controls, David C. Randall, Richard O. Speakman, Dennis L. Silcox, Laura V. Brown, David R. Brown, Ming C. Gong, Abhijit R. Patwardhan, L. Raymond Reynolds, Dennis G. Karounos, Don E. Burgess, Chikodi N. Anigbogu

Physiology Faculty Publications

We recorded via telemetry the arterial blood pressure (BP) and heart rate (HR) response to classical conditioning following the spontaneous onset of autoimmune diabetes in BBDP/Wor rats vs. age-matched, diabetes-resistant control (BBDR/Wor) rats. Our purpose was to evaluate the autonomic regulatory responses to an acute stress in a diabetic state of up to 12 months duration. The stress was a 15-s pulsed tone (CS+) followed by a 0.5-s tail shock. The initial, transient increase in BP (i.e., the "first component," or C₁), known to be derived from an orienting response and produced by a sympathetic increase in peripheral …

The Trna Synthetase Paralog Poxa Modifies Elongation Factor-P With (R)-Β-Lysine, Hervé Roy, S. Betty Zou, Tammy J. Bullwinkle, Benjamin S. Wolfe, Marla S. Gilreath, Craig J. Forsyth, William Wiley Navarre, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The lysyl-tRNA synthetase paralog PoxA modifies elongation factor P (EF-P) with α-lysine at low efficiency. Cell-free extracts containing non–α-lysine substrates of PoxA modified EF-P with a change in mass consistent with addition of β-lysine, a substrate also predicted by genomic analyses. EF-P was efficiently functionally modified with (R)-β-lysine but not (S)-β-lysine or genetically encoded α-amino acids, indicating that PoxA has evolved an activity orthogonal to that of the canonical aminoacyl-tRNA synthetases.

Association Between T Cells-Related Gene Expression And Fibrosis Progression In Hcv Recurrence Disease., Alexander Philip

Theses and Dissertations

Hepatitis C virus (HCV) is the major cause of chronic hepatitis worldwide and a leading cause for liver transplant. Unfortunately, graft HCV infection is a universal phenomenon despite of pre-transplant prophylactic strategies. Acute HCV infection and innate immune responses elicit an inflammatory scenario that triggers the recruitment of adaptive immune response cells. Of those chronically infected, 30% experience accelerated fibrosis with concomitant cirrhosis development within 5 years post-LT and require re-transplant. With many patients responding unfavorably to antivirals and ineffective vaccines, much attention is now placed on T cell immunity in controlling HCV infection. This study represents a retrospective analysis …

Molecular Pathways Involved In Calcineurin Inhibitor Nephrotoxicity In Kidney Allograft Transplants, Huong Nguyen

Theses and Dissertations

ABSTRACT MOLECULAR MECHANISMS AND GENE SIGNATURES INVOVLED IN CALCINEURIN INHIBITOR NEPHROTOXICITY IN KIDNEY ALLOGRAFT By Huong Le Diem Nguyen, M.S. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Physiology at Virginia Commonwealth University. Virginia Commonwealth University, 2011. Major Director: Valeria Mas, Ph.D. Associate Professor, Department of Surgery and Pathology Director of Molecular Transplant Research Laboratory, Division of Transplant Calcineurin inhibitors (CNI), cyclosporin A and tacrolimus, are potent immunosuppressive agents but induce toxicities causing damages and graft dysfunction, and have been suggested to contribute to late-term loss of graft in kidney transplant …

Mechanisms Of Prenatal High-Salt "Fetal Programming" Resulting In Stress Hyperresponsiveness In The Adult Female Offspring In The Sprague Dawley Rat., Clinton L. Johnson

Theses and Dissertations

Female offspring of Sprague-Dawley rats fed a high-salt diet (HS) during pregnancy show an enhancement of mean arterial pressure (MAP) and heart rate (HR) response to acute stress in adulthood compared to offspring whose mothers were fed a normal-salt diet (NS) [1]. In the present study, we first examined the expression of soluble epoxide hydrolase (SEH) protein in brain tissue. Whole brains were collected and SEH gene (EPHX2) mRNA and SEH protein expression were analyzed using RT-PCR and Western blot, respectively. mRNA levels were relatively decreased in high-salt rats (1.0 ± 0.32 NS vs 0.39 ± 0.07 HS, n=6). However, …

Physiologically-Based Pharmacokinetic Modeling For Predicting Drug-Drug Interactions, David M. Ng, Ali Navid

STAR Program Research Presentations

Dynamics of interactions between the drugs caffeine and ciprofloxacin are predicted using physiologically-based pharmacokinetic (PBPK) modeling. Pharmacokinetic means the model determines where the drugs are distributed in the body over time. Physiologically-based means the anatomy and physiology of the human body is reflected in the structure and functioning of the model. Multiple drugs can interact to increase or decrease their beneficial and/or undesired effects. This is important because some common substances, such as caffeine in coffee and soft drinks, are actually drugs that affect the body. By implementing the model as a computer program, it is relatively straightforward to perform …

Interspecies Comparison Of Αii-Spectrin Abundance Between Chinook Salmon And Steelhead, Brielle D. Kemis, Ann L. Miracle, Katie A. Wagner, Christa M. Woodley

STAR Program Research Presentations

Salmonids, such as Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss), are a staple economic, recreational, tribal, and environmental resource, yet many populations are unsustainable. This study was part of a broad scale effort to monitor the impact of downstream migration obstacles on juvenile salmonid health and survival, which is an essential step towards increasing Smolt-to-Adult Return ratios (SARs). The objective of this study was to determine if juvenile Chinook salmon and steelhead exhibit differing quantities of alphaII-Spectrin Breakdown Products (SBDPs) over two consecutive spring migration periods, indicative of neurogenesis rate and/or biological response to head …

The Proteomic Response Of Ciona Intestinalis To Ocean Acidification And Acute Heat Stress: Impacts Of Global Climate Change In Coastal Marine Systems, Michael Dennis Dwyer Jr.

Biological Sciences

No abstract provided.

Regulation Of Endothelial Nitric Oxide Synthase In Pulmonary Myofibroblasts, Jonathan David Faughn

Masters Theses & Specialist Projects

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease leading to decreased lung volume and eventual respiratory failure. At present, the median post-diagnosis lifespan is between three and six years. Myofibroblasts are collagen-secreting cells essential for wound healing, but also implicated in the fibroproliferation and extra cellular matrix deposition commonly seen in IPF. The nitric oxide (NO) signaling pathway is implicated in protomyofibroblast to myofibroblast transition and regulation. Previous work has shown that in pulmonary myofibroblasts, endothelial nitric oxide synthase (eNOS) is the primary NOS isoform expressed. The current study used cultured rat pulmonary myofibroblasts between passages two and five …

The Role Of The Androgen Receptor Cofactor P44/Wdr77 In Astrocyte Activation, Bryce H. Vincent

Dissertations and Theses (Open Access)

Astrogliosis is induced by neuronal damage and is also a pathological feature of the major aging-related neurodegenerative disorders. The mechanisms that control the cascade of astrogliosis have not been well established. In a previous study, we identified a novel androgen receptor (AR)-interacting protein (p44/WDR77) and found that it plays a critical role in the control of proliferation and differentiation of prostate epithelial cells. In the present study, we found that deletion of the p44 gene in the mouse brain caused accelerated aging with dramatic astrogliosis. The p44/WDR77 is expressed in astrocytes and loss of p44/WDR77 expression in astrocytes leads to …

Embryonic Development Of The Grass Shrimp, Palaemonetes Pugio, And The Influence Of Salinity On Cardiac Physiology, Amie Lynn Romney

UNLV Theses, Dissertations, Professional Papers, and Capstones

The grass shrimp, Palaemonetes pugio, inhabit the brackish waters along the Atlantic coast of North America and are a key component of the estuarine ecosystem. These decapod shrimp can tolerate large fluctuations in environmental parameters including daily and seasonal fluctuations in salinity between 0 to 55 parts per thousand (seawater at 30-32 ppt). Any observed distribution patterns of adult P. pugio in relation to salinity may be accounted for by their relative ability to tolerate a range in salinity and their ability to maintain internal water volumes and cardiac performance in the earliest life stage, the embryonic period. This thesis …

Proceedings Of The Ii International Meeting In Exercise Physiology

International Journal of Exercise Science: Conference Proceedings

Proceedings of the II International Meeting in Exercise Physiology. Meeting held May 5-7, 2011. This meeting was promoted by the Exercise Physiology Laboratory / UFSCar, in collaboration with UNICAMP and UNIMEP universities. The event was designed to bring Brazilian scientists, especially from São Paulo state that work with Exercise Physiology and Health. The main objective was to put together these students and scientists interested in developing joint researches in this area.

Opioid Addiction Treatments During Pregnancy And Their Effects On Axonal Growth And Myelination In The Developing Central Nervous System, Manisha Magar

Theses and Dissertations

Treatment with buprenorphine represents a promising alternative for pregnant opioid addicts but there is a need to understand potential effects on nervous system development. We previously showed effects of perinatal exposure to buprenorphine on axonal caliber and myelination in 26-day-old rat corpus callosum. These changes, detected at the end of rapid brain myelination and accompanied by earlier oligodendrocyte maturation, suggested interference with mechanisms coordinating axonal growth and myelination. To better understand buprenorphine actions and to establish whether these effects extend to the spinal cord, we analyzed the corpus callosum and corticospinal tract at 16 days of age, just before the …

Programming

International Journal of Exercise Science: Conference Proceedings

Programming for the II International Meeting in Exercise Physiology

Exercise-Induced Lymphocyte Apoptosis And Relationship With Level Of Lactate In Smokers And Non-Smokers, Kyung-Shin Park, Yang Lee

International Journal of Exercise Science

Purposes of this study were 1) to examine the exercise intensity where lymphocyte apoptosis index (AI) is significantly increased in smokers and non-smokers, 2) to find out whether AI is associated with level of lactate (L). METHODS: Fourteen healthy untrained smokers (≥ 1 pack year, n=7) and non-smokers (n=7) aged 18 to 26 were recruited. Each subject conducted three treadmill runs at different intensities randomly. Running distance for all three runs was equivalent to 30 minute run at 70% VO2max. AI and L were analyzed at rest (Pre), immediately after (Post), and 1 h following (1 h post) each run. …

Presence Of Observers Increases One Repetition Maximum In College-Age Males And Females, Steven C. Baker, Alan P. Jung, John K. Petrella

International Journal of Exercise Science

Purpose: To determine if the presence of observers affects muscular strength performance in college-age males and females. Methods: Twenty-five women and 24 men participated in the study. Two counter-balanced trials were performed in which participants completed 1-RM tests in bench press and leg press. During one trial, two members of the opposite gender observed the 1-RM tests. During the other trial there were no observers, other than the tester. Results: 1-RM for females increased 3.4±0.8 lbs on bench press (p<.001) and increased 9.2±3.8 lbs on leg press (p=.025) when observers were present. 1-RM for males increased 4.2±1.1 lbs on bench press (p=.001) and increased 18.8±5.2 lbs on leg press (p=.002) with observers present. There was no difference in the percent increase in 1-RM between males and females for either leg press (p=.71) or bench press (p=.08). Conclusion: College-age males and females lifted more weight during a 1-RM test when observers were present.

Effects Of Backward Walking On Hamstring Flexibility And Low Back Range Of Motion, Chet R. Whitley, Janet S. Dufek

International Journal of Exercise Science

The purpose of the study was to examine the effects of backward walking on hamstring flexibility and low back range of motion. Ten healthy female volunteers (29.9±10.0 yr; 165.1±8.2 cm; 68.53±18.4 kg) completed pre-post laboratory testing surrounding a 4-week intervention of backward walking. During the pretest, each participant walked forward on a treadmill at a preferred velocity for 3-5 min. A biaxial electrogoniometer was secured externally to the low back and a sit-and-reach test was performed. Each participant then walked backward at their preferred pace on a treadmill for 10 min, during which time low back motion data were obtained …

Intermittent Vs Continuous Graded Exercise Test For Vo2max In College Soccer Athletes, Constance M. Mier, Ryan P. Alexander

International Journal of Exercise Science

The purpose of this study was to determine if a 1-min active recovery between stages during a graded exercise test (GXT) would result in a higher stage intensity and maximum oxygen uptake in college soccer athletes. Eleven athletes completed two GXT protocols on separate days. Each GXT consisted of 2-min stages performed at a constant running speed and incremental increases of 2.5% grade. One GXT was performed continuously and the other was intermittent with 1-min active recovery between each stage. Tests were performed to volitional fatigue. Following the each GXT and a 10-min active recovery period, participants performed a verification …

Accuracy Of Consumer Grade Bioelectrical Impedance Analysis Devices Compared To Air Displacement Plethysmography, Janet T. Peterson, Wendy E. S. Repovich, Carlye R. Parascand

International Journal of Exercise Science

The purpose of this study was to examine the accuracy of percent body fat estimates from seven different bioelectrical impedance analysis (BIA) models and a seven-site skin fold formula (SKF) compared with air displacement plethysmography (ADP) in females. Eighty-two female volunteers ranging from 19-67 years (31.96 ± 1.39) enrolled in this study. Body composition was assessed by seven site skin folds (SKF), ADP, Tetrapolar BIA (TBIA), and five consumer grade BIA devices: finger to finger (FF), hand to hand (HH) and three different leg to leg (LL1, LL2, LL3) models. In addition, LL3 was analyzed using the athletic (LL3a) and …

Does The Friel Anaerobic Threshold Test Accurately Detect Heart Rate Deflection In Trained Cyclists?, Willie K. Yuen, Shad R. Schreiner, Donald L. Hoover, Janice K. Loudon, Sandra A. Billinger

International Journal of Exercise Science

The Friel Anaerobic Threshold Test (FATT) has been used to determine anaerobic threshold (AT). The FATT suggests AT occurs near the heart rate deflection point (HRDP) at a rating of perceived exertion (RPE) of 17. Purpose: The primary purpose of this study was to determine 1) whether the HRDP could be determined using the FATT, 2) examine differences between HRVT and HR that coincided Borg’s rating of perceived exertion (RPE) of 17, and 3) if riding position (hoods or aero) would influence performance. Methods: Fourteen male cyclists (30.4 ± 7.41years of age; 151.8 ± 60.4 cycled miles/week) participated in the …

Quantitative Analysis Of Contactin-Associated Protein And Voltage-Gated Sodium Channel Isoform 1.6 Following Experimental Diffuse Traumatic Brain Injury, Daniel Gardiner

Theses and Dissertations

Traumatic axonal injury (TAI) contributes to the mortality and morbidity following diffuse traumatic brain injury (TBI). Previous work has shown that following TBI, alterations in the molecular domains of axons result in TAI. It is currently posited that injury induced ionic flux is responsible for activating deleterious proteolytic cascades, resulting in altered distributions of axonal components. However, the underlying mechanism of this progressive pathology remains elusive. This study further explores the hypothesis that altered molecular domains contributes to the progressive intra-axonal changes that characterize TAI. Using a rodent model of impact acceleration TBI we examined the expression of nodal and …

Calcineurin Is Required For Trpv1-Induced Ltd Of Ca1 Stratum Radiatum Interneurons, Tyron Deray Jensen

Theses and Dissertations

Learning and memory in the brain are thought to be dependent on synaptic plasticity. In response to sensory input, synapses can be strengthened or weakened, known as long-term potentiation or long-term depression (LTD), respectively. Transient receptor potential vanilloid 1 (TRPV1) has been shown to mediate a novel form of presynaptic LTD in hippocampal interneurons. TRPV1 is currently being heavily studied in the PNS and being targeted by pharmaceuticals for its anti-nociceptive and anti-inflammatory properties. However, much less is known regarding TRPV1 function in the CNS, including the signal mechanism mediating hippocampal LTD despite its obvious importance. Here we performed whole-cell …

Receptor Influences In Girk Current Activation And Desensitization, Gyu Park

Theses and Dissertations

G protein-coupled receptors (GPCRs) are seven-transmembrane domain receptors that sense extracellular signal and activate intracellular signaling pathways. Metabotropic glutamate receptor 2 (mGluR2) is one of the GPCRs coupled to Gi/o proteins whose Gβγ subunits stimulate G protein-gated inwardly rectifying K+ channels (GIRKs). Previous experiments demonstrated that in planar lipid bilayer both active forms of G proteins [Gα (GTPγS-stimulated) and Gβγ subunits] were required to activate GIRK channels in the absence of the receptor, but surprisingly, the Gβγ subunit alone could activate GIRK channel in the presence of GPCR. Currently, it is not clear whether GPCRs play a role beyond catalyzing …

The Effects Of Β-Amyloid On Α7 Nicotinic Acetylcholine Receptors Expressed In Xenopus Oocytes, Malia L. Anderson

Theses and Dissertations

The exact mechanism and progression of Alzheimer's disease (AD) at present is not fully understood. In patients suffering from AD, damage to the hippocampal region and impairment of learning and memory is present. It is also known that a buildup of β-amyloid plaques occur in AD patients and that β-amyloid interacts with some subtypes of neuronal nicotinic acetylcholine receptors (neuronal nAChRs). These receptors are composed of five subunits. The most prevalent nAChR subunit composition through the brain as a whole is α7. Previous data produced from our lab suggests that α7 nAChRs are also one of the most prevalent subunits …

Plantar Pressure Distribution Differences In Physically Active Individuals With And Without Functional Ankle Instability During A Side Cut, J'Nai Pittman

Human Movement Studies & Special Education Theses & Dissertations

Context: Functional ankle instability (FAI) is a popular condition in the physically active population. There is a surplus of evidence to demonstrate how FAI decreases proprioception, balance, and overall athletic performance. However, to date there is no evidence that demonstrates how F AI correlates to alterations in plantar pressure distribution differences in a physically active population while completing athletic tasks. Objective: To assess differences in plantar pressure distributions while completing a side cut in individuals with and without FAI. Design: Observational case-control. Setting: Outdoor field turf and research laboratory. Participants: Fifty ankles from physically active individuals (FAI: age= 21.47±3.02 yrs; …

Effects Of Diet Type And Supplementation Of Glucosamine, Chondroitin, And Msm On Body Composition, Functional Status, And Markers Of Health In Women With Knee Osteoarthritis Initiating A Resistance-Based Exercise And Weight Loss Program, Teresa Magrans-Courtney, Colin Wilborn, Christopher Rasmussen, Maria Pontes Ferreira, Lori Greenwood, Bill Campbell, Chad M. Kerksick, Erica Nassar, Rui Li, Mike Iosia, Matt Cooke, Kristin Dugan, Darryn Willoughby, Luann Soliah, Richard B. Kreider

Nutrition and Food Science Faculty Research Publications

Background: The purpose of this study was to determine whether sedentary obese women with knee OA initiating an exercise and weight loss program may experience more beneficial changes in body composition, functional capacity, and/or markers of health following a higher protein diet compared to a higher carbohydrate diet with or without GCM supplementation.

Methods: Thirty sedentary women (54 ± 9 yrs, 163 ± 6 cm, 88.6 ± 13 kg, 46.1 ± 3% fat, 33.3 ± 5 kg/m²) with clinically diagnosed knee OA participated in a 14-week exercise and weight loss program. Participants followed an isoenergenic low fat higher …

Store-Operated Ca(2+) Entry (Soce) Contributes To Normal Skeletal Muscle Contractility In Young But Not In Aged Skeletal Muscle, Angela M. Thornton, Xiaoli Zhao, Noah Weisleder, Leticia S. Brotto, Sylvain Bougoin, Thomas M. Nosek, Michael B. Reid, Brian Hardin, Zui Pan, Jianjie Ma, Jerome Parness, Marco Brotto

Physiology Faculty Publications

Muscle atrophy alone is insufficient to explain the significant decline in contractile force of skeletal muscle during normal aging. One contributing factor to decreased contractile force in aging skeletal muscle could be compromised excitation-contraction (E-C) coupling, without sufficient available Ca(2+) to allow for repetitive muscle contractility, skeletal muscles naturally become weaker. Using biophysical approaches, we previously showed that store-operated Ca(2+) entry (SOCE) is compromised in aged skeletal muscle but not in young ones. While important, a missing component from previous studies is whether or not SOCE function correlates with contractile function during aging. Here we test the contribution of extracellular …

A Call To (Physical) Activity, A Call To Action, Karen Richardson, Sam Baumgarten

Bridgewater Review

No abstract provided.

Ischemia Impairs Vasodilation In Skeletal Muscle Resistance Artery, Kyle Remington Struthers

Master's Theses

Functional vasodilation in arterioles is impaired with chronic ischemia. We sought to examine the impact of chronic ischemia and age on skeletal muscle resistance artery function. To examine the impact of chronic ischemia, the femoral artery was resected from young (2-3mo) and adult (6-7mo) mice and the profunda femoris artery diameter was measured at rest and following gracilis muscle contraction 14 days later using intravital microscopy. Functional vasodilation was significantly impaired in ischemic mice (14.4±4.6% vs. 137.8±14.3%, p<0.0001 n=8) and non-ischemic adult mice (103.0±9.4% vs. 137.8±14.3%, p=0.05 n=10). In order to analyze the cellular mechanisms of the impairment, a protocol was developed to apply pharmacological agents to the experimental preparation while maintaining tissue homeostasis. Endothelial and smooth muscle dependent vasodilation were impaired with ischemia, 39.6 ± 13.6% vs. 80.5 ± 11.4% and 43.0 ± 11.7% vs. 85.1 ± 10.5%, respectively. From this data, it can be supported that smooth muscle dysfunction is the reason for the observed impairment in arterial vasodilation.

Possible Molecular Mechanism To Account For Wavelength Dependence Of Equilibration Rates Of Patman And Laurdan In Phosphatidylcholine Bilayers, Hannabeth A. Franchino

Theses and Dissertations

Patman is a fluorescent membrane probe related to Laurdan. The structural distinctions between the two probes are the lengths of the aliphatic tails (eleven carbons in Laurdan and fifteen in Patman) and the presence of a trimethylammonium group on Patman that produces a positively-charged head. Preliminary studies exploring Patman as a probe to detect membrane properties during apoptosis revealed that the fluorescence intensity of two edges of the emission spectrum (435 and 500 nm) stabilizes at different rates as the probe binds to the cell membrane. To test whether these differences represent dissimilarities in probe binding to ordered and disordered …