Physiology Commons^™

Qt Prolongation Is Associated With Increased Mortality In End Stage Liver Disease, Sun Moon Kim, Bennet George, Diego Alcivar-Franco, Charles L. Campbell, Richard Charnigo, Brian P. Delisle, Jonathan Hundley, Yousef Darrat, Gustavo Morales, Samy-Claude Elayi, Alison L. Bailey

Internal Medicine Faculty Publications

AIM

To determine the prevalence of QT prolongation in a large series of end stage liver disease (ESLD) patients and its association to clinical variables and mortality.

METHODS

The QT interval was measured and corrected for heart rate for each patient, with a prolonged QT cutoff defined as QT > 450 ms for males and QT > 470 ms for females. Multiple clinical variables were evaluated including sex, age, serum sodium, international normalized ratio, creatinine, total bilirubin, beta-blocker use, Model for End-Stage Liver Disease (MELD), MELD-Na, and etiology of liver disease.

RESULTS

Among 406 ESLD patients analyzed, 207 (51.0%) had QT prolongation. …

Constitutive Activation Of Kappa Opioid Receptors At Ventral Tegmental Area Inhibitory Synapses Following Acute Stress., Abigail M Polter, Kelsey Barcomb, Rudy W Chen, Paige M Dingess, Nicholas M Graziane, Travis E Brown, Julie A Kauer

Pharmacology and Physiology Faculty Publications

Stressful experiences potently activate kappa opioid receptors (κORs). κORs in the ventral tegmental area regulate multiple aspects of dopaminergic and non-dopaminergic cell function. Here we show that at GABAergic synapses on rat VTA dopamine neurons, a single exposure to a brief cold-water swim stress induces prolonged activation of κORs. This is mediated by activation of the receptor during the stressor followed by a persistent, ligand-independent constitutive activation of the κOR itself. This lasting change in function is not seen at κORs at neighboring excitatory synapses, suggesting distinct time courses and mechanisms of regulation of different subsets of κORs. We also …

Pharmacology, Pharmacokinetics, And Metabolism Of The Dna-Decoy Ayx1 For The Prevention Of Acute And Chronic Post-Surgical Pain, Julien Mamet, Scott Harris, Michael Klukinov, David C. Yeomans, Renee R. Donahue, Bradley K. Taylor, Kelly Eddinger, Tony Yaksh, Donald C. Manning

Physiology Faculty Publications

Background: AYX1 is an unmodified DNA-decoy designed to reduce acute post-surgical pain and its chronification with a single intrathecal dose at the time of surgery. AYX1 inhibits the transcription factor early growth response protein 1, which is transiently induced at the time of injury and triggers gene regulation in the dorsal root ganglia and spinal cord that leads to long-term sensitization and pain. This work characterizes the AYX1 dose-response profile in rats and the link to AYX1 pharmacokinetics and metabolism in the cerebrospinal fluid, dorsal root ganglia, and spinal cord.

Results: The effects of ascending dose-levels of AYX1 on mechanical …

Casein Protein Supplementation In Trained Men And Women: Morning Versus Evening, Jose Antonio

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 479-486, 2017. The purpose of this investigation was to determine the effects of casein supplementation (54 grams) in the morning (Casein-MOR) or evening (Casein-EVE) (90 minutes or less prior to sleep) on measures of body composition and exercise performance in trained men and women. Twenty-six healthy men and women who had been training regularly for greater than 12 months completed this 8-week study (mean±SD; Casein-MOR group [n=14, seven male, seven female]: 30.0±8.2 yr; 170.7±9.5 cm; 70.9±13.9 kg. Casein-EVE group [n=12, nine male, three female]: 28.9±9.5 yr; 172.9±7.3 cm; 72.6±10.9 kg). Subjects in each group …

Assessment Of Differences In The Anthropometric, Physiological And Training Characteristics Of Finishers And Non-Finishers In A Tropical 161-Km Ultra-Marathon, Philip Ls Tan, Frankie Hy Tan, Andrew N. Bosch

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 465-478, 2017. This study aimed to compare and determine the differences in the physiological, anthropometric and training characteristics of the finishers (FIN) and non-finishers (N-FIN) in a 161-km race. Two groups of runners (FIN; N=12 and N-FIN; N=14) completed a series of anthropometric and physiological measurements over two separate sessions at least three weeks prior to the race. Training sessions starting from six weeks prior to the race were recorded. Sum of 7 skinfolds, arm and calf girths, VO2max and peak treadmill speed (PTS) were taken during session 1 while the lactate threshold (LT) …

Demands Of Simulated Commuting Using An Electrically Assisted Bicycle, D. Taylor La Salle, Robert Shute, Matthew Heesch, Dustin Slivka

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 454-464, 2017. The American College of Sports Medicine (ACSM) recommends adults participate in weekly aerobic activity for a minimum of 30 minutes moderate intensity exercise 5 days per week or 20 minutes of vigorous activity 3 days per week. The electrically assisted bicycle may help individuals achieve the ACSM’s aerobic recommendations and introduce inactive individuals to physical activity. To compare the physiological requirements of riding a bicycle with electric pedal assist versus non-assist among healthy active young adults. 6 males and 6 females completed two randomized cycling trials using electric pedal assist (PAB) and …

Self-Optimization Of Stride Length Among Experienced And Inexperienced Runners, Iain Hunter, James B. Tracy, Jared Ward

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 446-453, 2017. Experienced runners appear to naturally select a stride length which is optimal for minimizing oxygen uptake. However, whether this ability is naturally built into the human body or whether it is learned through experience has not been previously tested. This study investigated whether inexperienced runners are as capable as experienced runners of self-optimizing stride length to minimize oxygen uptake. Thirty-three subjects (nineteen experienced and fourteen inexperienced) ran for twenty-minutes while preferred and economical stride lengths were measured. A t-test checked for differences between the experienced and inexperienced groups in the percent increase …

A Correlational Study Of Religiosity And Total Body Fat Composition In Collegiate Populations, Courtney Bostrum, Ryan Radtke, Seth A. Paradis

Applied Health Sciences Student Works

Previous research indicates rising levels of body fat composition in Americans. One contributing factor may be an individual’s degree of religiosity. Although not all, most studies have found religiosity to negatively impact body mass index (BMI) and obesity levels. Minimal research has been conducted regarding the relations between religiosity and body fat percentage. Not only do the overall increasing trends in body fat composition cost the American people between $48 and $68 billion per year in medical care, but excess body fat increases the risk for diabetes, cardiovascular diseases and cancer. Religious factors have been shown to play a role …

Diabetic Cardiomyopathy: An Immunometabolic Perspective., Paras K. Mishra, Wei Ying, Shyam Sundar Nandi, Gautam K. Bandyopadhyay, Kaushik K. Patel, Sushil K. Mahata

Journal Articles: Cellular & Integrative Physiology

The heart possesses a remarkable inherent capability to adapt itself to a wide array of genetic and extrinsic factors to maintain contractile function. Failure to sustain its compensatory responses results in cardiac dysfunction, leading to cardiomyopathy. Diabetic cardiomyopathy (DCM) is characterized by left ventricular hypertrophy and reduced diastolic function, with or without concurrent systolic dysfunction in the absence of hypertension and coronary artery disease. Changes in substrate metabolism, oxidative stress, endoplasmic reticulum stress, formation of extracellular matrix proteins, and advanced glycation end products constitute the early stage in DCM. These early events are followed by steatosis (accumulation of lipid droplets) …

Hypotensive Responses Of Reciprocal Supersets Versus Traditional Resistance Training In Apparently Healthy Men, Claudio Melibeu Bentes, Pablo B. Costa Corresponding Author, Victor Gonçalves Corrêa Neto, Roberto Simão, Gabriel Andrade Paz, Marianna Maia, Tiago Figueiredo, Gabriel Rodrigues Neto, Jefferson S. Novaes, Humberto Miranda

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 434-445, 2017. The purpose of this study was to compare the hypotensive responses of reciprocal supersets (SS) versus traditional training (TRAD) methods. Thirteen men with at least five years of recreational experience in resistance training (RT) volunteered for the study. When completing the TRAD protocol, participants performed the following exercises separately in sequence: chest press (CP), low row (LR), leg extension (LE), leg curl (LC), pull down (PD), and shoulder press (SP). The SS method required participants to complete the same exercises as in the TRAD protocol, but exercises were coupled such that muscles …

Passion For Academics And Problematic Health Behaviors, Alex T. Bureau, Selen Razon Ph.D, Umit Tokac, Bryan K. Saville, Lawrence W. Judge

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 417-433, 2017. According to the Dualistic Model of Passion (39), passion entails valuing, liking, and spending time on an activity. The Dualistic Model also posits two types of passion for activities: harmonious passion (individual voluntarily engages in the activity) and obsessive passion (individual is compelled to engage in the activity). The purpose of the present study was to examine the possible links between college students’ passion for academic activities and problematic health behaviors including smoking, excessive drinking, exercise addiction, disordered eating, and sleepiness, which is a possible indicator of sleep deprivation. Participants (n = …

Resistance Training Contribute To The Aerobic Components Of An Exercise Session In Adults But Not As Much In Older Adults, Neha Bharti, Travis Hrubeniuk, Andrea Mayo, Martin Senechal, Danielle R. Bouchard

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 406-416, 2017. Previous research has indicated that active adults are able to achieve moderate intensity as measured via heart rate during a typical resistance training (RT) session. The main objective was to identify if overweight adults and older adults can reach aerobic moderate intensity at a rate comparable to adults displaying a recommended body mass index. Twenty participants in each group were asked to visit a fitness facility twice if they self-reported doing RT for a minimum two days per week. At the first session baseline characteristics and maximal lifting capacity for each RT …

College Students’ Knowledge Of Recovery Beverage Serving Sizes, Stephanie Lewis, Victoria Baxter, Kim Spaccarotella, Walter Andzel

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 397-405, 2017. Previous research suggests that chocolate milk may be a beneficial recovery beverage, yet little is known about how athletes and students training for careers in sports science or health-related fields interpret recommended recovery beverage serving sizes. This study examined college students’ ability to correctly apply serving size recommendations for chocolate milk and protein powder used during post-exercise recovery and assessed usual consumption of milk as a recovery beverage. College students (34 women, 39 men) poured the amount of chocolate milk they would consume within 90 minutes after exercise unaided and with the …

The Effect Of Acute Hyperglycemia On Muscular Strength, Power And Endurance, Franklin Lime-Ma, Joshua A. Cotter, Evan E. Schick

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 390-396, 2017. The purpose of this study was to elucidate the impact of acute hyperglycemia on skeletal muscle strength, power, and endurance. Ten male collegiate athletes (age 21.5 ± 1.5 years, height 186 ± 2.03 cm, body mass 108.8 ± 7.6 kg) participated in 2 testing sessions, separated by 7 days and randomized for either high glucose (HG) or control (C) treatment conditions. HG consumed a high glucose drink (2 g glucose/kg body weight) while controls consumed an isocaloric nutrition bar (40% protein, 30% fat, and 30% carbohydrate). Blood glucose (BC) levels for HG …

Better Health-Related Fitness In Youth: Implications For Public Health Guidelines, Mitch Barton, Allen W. Jackson, Scott B. Martin, James R. Morrow Jr., Trent A. Petrie, Christy A. Greenleaf

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 379-389, 2017. Public health guidelines for physical activity (PA) behaviors are being updated with 2018 as a proposed release date. Currently, ≥60 minutes of daily PA are recommended for youth. Thus, the purpose of this study was to investigate the association between reported days of aerobic PA and health-related fitness (HRF). Participants included 4448 students in grades 6-8. Self-reported days of ≥60 minutes of aerobic PA was obtained. HRF was assessed with FitnessGram. Discriminant analysis indicated that weekly days of aerobic PA related to HRF. Adolescents who participated in ≥5 days of weekly aerobic …

Antiproliferative Effects Of Hibernating American Bullfrog (Rana Catesbeiana) Blood Plasma On Thp-1 Cells, Sean Robbins

Annual Graduate Student Symposium

Hibernation is an incredible adaptation that allows an organism to go dormant during the winter, when food is scarce. Much is unknown physiologically about hibernation, and most current research comes from mammalian models. During hibernation, the cells of mammals are impeded from going through mitosis. 13-lined ground squirrels (Ictidomys tridecemlineatus) and woodchucks (Marmota monax) have a protein, alpha-2-macroglobulin, in their blood plasma, which has significant antiproliferative effects on spleen cells. The goal of my study was to determine if an exothermic organism, the American Bullfrog (Rana catesbeiana), also actively suppresses mitosis while hibernating and if so, determine if it is …

Time Course Of Changes In Neuromuscular Responses At 30% Versus 70% 1 Repetition Maximum During Dynamic Constant External Resistance Leg Extensions To Failure, Cory M. Smith, Terry J. Housh, Ethan C. Hill, Richard J. Schmidt, Glen O. Johnson

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 365-378, 2017. The purpose of the current study was to examine the time course of changes in neuromuscular responses from the vastus medialis (VM) during low versus high intensity dynamic constant external resistance (DCER) leg extension muscle actions to failure. Thirteen men performed DCER leg extensions to failure at 30% and 70% 1-repetition maximum (1-RM) as well as 1-RM measurements pretest and posttest. Electromyogaphy and mechanomyographic signals were measured from the VM. There were no differences in neuromuscular responses pretest versus posttest 1-RM. There were time-dependent differences between the 30% and 70% 1-RM protocols. …

Effects Of Different Number Of Sets Of Resistance Training On Flexibility, Thalita B. Leite, Pablo B. Costa, Richard D. Leite, Jefferson S. Novaes, Steven J. Fleck, Roberto Simão

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 354-364, 2017. The aim of this study was to investigate the effects of six months of training with three different number of sets of resistance training on flexibility in young men. Forty-seven men (mean ± SD age = 24 ± 1yrs; body mass = 79.39 ± 9.12 kg; height = 174.5 ± 5.6 cm) were randomly divided into three training groups performing either one set (G1S), three sets (G3S), or five sets (G5S) of all exercises in a resistance training session or a control group (CG). All groups were assessed pre- and post-training for …

A Low Dose Caffeine And Carbohydrate Supplement Does Not Improve Athletic Performance During Volleyball Competition, David Pfeifer, Kelsey Arvin, Nicholas Haynes, Courtney Herschberger, Matthew S. Renfrow

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 340-353, 2017. Dietary supplements are widely used to enhance sport performance and the combination of carbohydrate and caffeine (CHO+CAF) has yielded particularly high performance gains. Though the effects of a CHO+CAF supplement have been studied in a laboratory environment, little research exists on the effects of supplementation during competition. Therefore, the purpose of this study was to determine the effects of a CHO+CAF supplement on athletic performance in competition. Eight female collegiate volleyball players completed three testing sessions under three different conditions separated by approximately one week each: CHO+CAF supplement, placebo (PBO), and control …

The Relationship Of Living Environment With Behavioral And Fitness Outcomes By Sex: An Exploratory Study In College-Aged Students, Kaelah Shaffer, Melissa Bopp, Zack Papalia, Dangaia Sims, Christopher M. Bopp

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 330-339, 2017. Although physical activity (PA) is associated with several health benefits, there is a marked decline during college years, which is an influential period for the development of health behaviors. This study examined the relationship of neighborhood and living environment with behavioral (PA and sedentary behavior) and fitness outcomes by sex. Participants were college students that participated in a fitness assessment, followed by a survey that measured self-reported exercise and perception of one’s environment (sidewalks, crime, traffic, access to PA resources in their neighborhood and/or apartment complex). Pearson correlations examined the relationship between …