Physiology Commons^™

The Reduction Of Metabolic Cost While Using Handrail Support During Inclined Treadmill Walking Is Dependent On The Handrail-Use Instruction, Cory Hofmann, Connor Dougherty, Hagop Abkarian, Michele Fox, Paul Juris

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 339-345, 2014. Inclined treadmill walking is a commonly performed activity to increase cardiovascular health. Handrail support on a treadmill provides an individual the opportunity to change their posture with respect to the walking surface. Differences in metabolic cost during inclined walking due to postural changes with handrail use are unknown. To test the hypothesis that metabolic cost will differ depending on how handrail support is used, respiratory gas analysis was performed during inclined walking in 13 healthy subjects. Energy expenditure was quantified while each subject walked in four conditions: 5% incline unsupported, 10% …

Functional Morphology And Feeding Mechanics Of Billfishes, María Laura Habegger

USF Tampa Graduate Theses and Dissertations

Billfishes (marlins, spearfishes, sailfishes and swordfish) are one of the fastest and largest marine apex predators, and perhaps their most recognizable attribute is their bill or rostrum. The proposed function for this novel structure has ranged from hydrodynamic enhancement to defensive weaponry. However, the most supported hypothesis for its function has been linked to feeding. Billfishes have been observed to subdue their prey with their rostrum, either stunning or cutting them into pieces before ingestion. Due to their large body sizes and pelagic lifestyles a thorough investigation of the function of this structure has been logistically challenging. The goal of …

Lactate Threshold Comparison In Anaerobic Vs. Aerobic Athletes And Untrained Subjects, Matt Green, Jared Hornsby, Robert Pritchett, Kelley Pritchett

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 329-338, 2014. This study compared VO₂ max, lactate threshold (LT) and VO₂ at LT (VO_2LT) among aerobic athletes (ARA) (n=10), anaerobic athletes (ANA) (n=9) and untrained participants (UTS) (n=7). From a treadmill test to exhaustion, VO₂ max and LT (4 mmol·L^-1 blood lactate concentration) were assessed. Analysis of variance showed VO₂ max (ml·kg^-1·min^-1) was significantly greater for ARA (67.6 ± 9.4) than ANA (53.4 ± 6.4) and UTS (44.9 + 6.9), with ANA significantly greater than UTS. LT for ARA (82.9 + …

Longitudinal Trajectories Of Cholesterol From Midlife Through Late Life According To Apolipoprotein E Allele Status, Brian Downer, Steven Estus, Yuriko Katsumata, David W. Fardo

Physiology Faculty Publications

Background: Previous research indicates that total cholesterol levels increase with age during young adulthood and middle age and decline with age later in life. This is attributed to changes in diet, body composition, medication use, physical activity, and hormone levels. In the current study we utilized data from the Framingham Heart Study Original Cohort to determine if variations in apolipoprotein E (APOE), a gene involved in regulating cholesterol homeostasis, influence trajectories of total cholesterol, HDL cholesterol, and total: HDL cholesterol ratio from midlife through late life.

Methods: Cholesterol trajectories from midlife through late life were modeled using generalized …

Intercollegiate Cross Country Competition: Effects Of Warm-Up And Racing On Salivary Levels Of Cortisol And Testosterone, Kathleen V. Casto, Christopher Elliott, David A. Edwards

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 318-328, 2014. Team intercollegiate athletic competition is associated with an increase in salivary cortisol (C) and testosterone (T) in men and women. The present study was designed to determine the hormonal effects of warm-up and racing in cross country runners – a sport that has both individual and team components. Members of the Emory University men’s and women’s varsity cross country teams gave saliva samples before warm-up, after warm-up, and immediately after the finish of each of two intercollegiate invitational meets held one year apart in the same setting (2010, N = 10 …

Vo2 Reserve Vs. Heart Rate Reserve During Moderate Intensity Treadmill Exercise, Tanner J. Solheim, Brad G. Keller, Charles J. Fountaine

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 311-317, 2014. ­VO₂ and heart rate (HR) are widely used when determining appropriate training intensities for clinical, healthy, and athletic populations. It has been shown that if the % reserve (%R) is used, rather than % of max, HR and VO₂ can be used interchangeably to accurately prescribe exercise intensities. Thus, heart rate reserve (HRR) can be prescribed if VO₂ reserve (VO₂R) is known. Therefore, the purpose of this study was to compare VO₂ R and HRR during moderate intensity exercise (50%R). Physically active college students …

Muscle Activity In Single- Vs. Double-Leg Squats, Bradley A. Deforest, Gregory S. Cantrell, Brian K. Schilling

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 302-310, 2014. Muscular activity, vertical displacement and ground reaction forces of back squats (BS), rear-leg elevated split squats (RLESS) and split squats (SS) were examined. Nine resistance-trained men reported for two sessions. The first session consisted of the consent process, practice, and BS 1-repetition maximum testing. In the second session, participants performed the three exercises while EMG, displacment and ground reaction force data (one leg on plate) were collected. EMG data were collected from the gluteus maximus (GMX), biceps femoris (BF), semitendinosus (ST), rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), tibialis …

Occupational Sitting And Physical Activity Among University Employees, Charles J. Fountaine, Meredith Piacentini, Gary A. Liguori

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 295-301, 2014. The prevalence of overweight and obese in the U.S. has been thoroughly documented. With the advent of inactivity physiology research and the subsequent interest in sedentary behavior, the work environment has come under closer scrutiny as a potential opportunity to reverse inactivity. Therefore, the purpose of this study was to determine the sitting and physical activity (PA) habits among different classifications of university employees. University employees (n=625) completed an online survey based on the Occupational Sitting and Physical Activity Questionnaire (OSPAQ). Participants were instructed to describe time spent sitting, standing, walking, …

Time Spent In Mvpa During Exergaming With Xbox Kinect In Sedentary College Students, Chie Yang, Zachary Wickert, Samantha Roedel, Alexandria Berg, Alex Rothbauer, Marquell Johnson, Donald Bredle

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 286-294, 2014. The primary purpose of this study was to determine the amount of time spent in moderate-to-vigorous physical activity (MVPA) during a 30-minute bout of exergaming with the Xbox Kinect game console in sedentary college-aged students. A secondary purpose was to examine enjoyment level of participation in the selected exergame. Twenty college-aged students (14 females and 6 males) who self-reported being physically inactive and having no prior experience with the Xbox Kinect game “Your Shape Fitness Evolved 2012” Break a Sweat activity participated in the study. Participants came into the lab on …

Can Resistance Training Contribute To The Aerobic Components Of The Physical Activity Guidelines?, Travis J. Hrubeniuk, Neal Prokop, Semone Myrie, Martin Sénéchal, Danielle R. Bouchard

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 278-285, 2014. To evaluate if resistance training can reach Moderate to Vigorous Intensity (MVI) and contribute to the aerobic component of the international physical activity guidelines. Sixteen participants aged between 20 and 35 were recruited. Heart rate was recorded by heart rate monitor during a resistance training program. Based on maximal heart rate, time spent at MVI (55-69% of maximal heart rate) was calculated. Participants displayed a HR equal or above MVI for 51.5% ± 21.7% of time. When stratifying by lower and upper body sessions, that proportion was median (25-75th); 75.0% (32.5%-89.2%) …

The Acute Effects Of A Dynamic Stretching Protocol On Wingate Performance, Autumn S. Gipson Ms., Jamarious Jones, Elise N. Ritchey, Colby Murphy, Hope Grimes, John M. Coons

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 271-277, 2014. Stretching before performing anaerobic activity has been a highly debated subject, with studies finding differing results depending on the type (static, dynamic, etc.) and duration of the stretch. Furthermore, the effects of dynamic stretching (DS) on anaerobic performance have been minimally researched. The purpose of this study was to examine the effects a DS protocol had on power performance using a Wingate test (WAnT). College-aged male subjects were recruited for this study. Prior to experimental trials, subjects performed a familiarity WAnT trial. Subjects then performed the WAnT two more times, once …

The Relationship Between Change Of Direction Speed In The Frontal Plane, Power, Reactive Strength, And Strength, Brian T. Mccormick, James C. Hannon, Charlie A. Hicks-Little, Maria Newton, Barry Shultz, Nicole Detling, Warren B. Young

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 260-270, 2014. Change-of-direction speed (CODS) is an important quality to performance in multi-direction sports. The relationship between CODS in the frontal plane and power, strength, and reactive strength is largely unstudied. Twenty-three male college students participated in this study. The study used a Pearson’s product-moment correlation to measure the relationship between CODS, power, strength, and reactive strength. A lateral shuffle test was used as the measure of CODS. A lateral hop for distance was used as the measure of power in the frontal plane. A countermovement vertical jump test was used as the …

Family Of Flp Peptides In Caenorhabditis Elegans And Related Nematodes, Chris Li, Kyuhyung Kim

Publications and Research

Neuropeptides regulate all aspects of behavior in multicellular organisms. Because of their ability to act at long distances, neuropeptides can exert their effects beyond the conventional synaptic connections, thereby adding an intricate layer of complexity to the activity of neural networks. In the nematode Caenorhabditis elegans, a large number of neuropeptide genes that are expressed throughout the nervous system have been identified.The actions of these peptides supplement the synaptic connections of the 302 neurons, allowing for fine tuning of neural networks and increasing the ways in which behaviors can be regulated. In this review, we focus on a large …

The Non-Canonical Hydroxylase Structure Of Yfcm Reveals A Metal Ion-Coordination Motif Required For Ef-P Hydroxylation, Kan Kobayashi, Assaf Katz, Andrei Rajkovic, Ryohei Ishii, Owen E. Branson, Michael A. Freitas, Ryuichiro Ishitani, Michael Ibba, Osamu Nureki

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

EF-P is a bacterial tRNA-mimic protein, which accelerates the ribosome-catalyzed polymerization of poly-prolines. In Escherichia coli, EF-P is post-translationally modified on a conserved lysine residue. The post-translational modification is performed in a two-step reaction involving the addition of a β-lysine moiety and the subsequent hydroxylation, catalyzed by PoxA and YfcM, respectively. The β-lysine moiety was previously shown to enhance the rate of poly-proline synthesis, but the role of the hydroxylation is poorly understood. We solved the crystal structure of YfcM and performed functional analyses to determine the hydroxylation mechanism. In addition, YfcM appears to be structurally distinct from any …

Natural Selection On Thermal Performance In A Novel Thermal Environment, Michael L. Logan, Robert M. Cox, Ryan Calsbeek

Dartmouth Scholarship

Tropical ectotherms are thought to be especially vulnerable to climate change because they are adapted to relatively stable temperature regimes, such that even small increases in environmental temperature may lead to large decreases in physiological performance. One way in which tropical organisms may mitigate the detrimental effects of warming is through evolutionary change in thermal physiology. The speed and magnitude of this response depend, in part, on the strength of climate-driven selection. However, many ectotherms use behavioral adjustments to maintain preferred body temperatures in the face of environmental variation. These behaviors may shelter individuals from natural selection, preventing evolutionary adaptation …

Sleep Patterns In Collegiate Dancers, Beth Nicks, Jacque Price

e-Research: A Journal of Undergraduate Work

As college dance majors, the investigators have witnessed firsthand the effects that sleep and the lack thereof can have on the performance quality of University level dancing. It has been shown that lack of sleep can compromise nearly every physiological process such as memory, coordination, metabolism, and new learning (Wozny 2008). Studies on disruptions of the human circadian rhythms have shown that athletes involved in endeavors where sleep is restricted or totally deprived have severe consequences on behavior and performance. (Edwards 2007). However, the environment of college dance programs is different than athletics due to there being no off season. …

Mistranslation Of The Genetic Code, Adil Moghal, Kyle Mohler, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

During mRNA decoding at the ribosome, deviations from stringent codon identity, or “mistranslation,” are generally deleterious and infrequent. Observations of organisms that decode some codons ambiguously, and the discovery of a compensatory increase in mistranslation frequency to combat environmental stress have changed the way we view “errors” in decoding. Modern tools for the study of the frequency and phenotypic effects of mistranslation can provide quantitative and sensitive measurements of decoding errors that were previously inaccessible. Mistranslation with non‐protein amino acids, in particular, is an enticing prospect for new drug therapies and the study of molecular evolution.

Relaxed Substrate Specificity Leads To Extensive Trna Mischarging By Streptococcus Pneumoniae Class I And Class Ii Aminoacyl-Trna Synthetases, Jennifer Shepherd, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases provide the first step in protein synthesis quality control by discriminating cognate from noncognate amino acid and tRNA substrates. While substrate specificity is enhanced in many instances by cis- and trans-editing pathways, it has been revealed that in organisms such as Streptococcus pneumoniae some aminoacyl-tRNA synthetases display significant tRNA mischarging activity. To investigate the extent of tRNA mischarging in this pathogen, the aminoacylation profiles of class I isoleucyl-tRNA synthetase (IleRS) and class II lysyl-tRNA synthetase (LysRS) were determined. Pneumococcal IleRS mischarged tRNA^Ile with both Val, as demonstrated in other bacteria, and Leu in a tRNA sequence-dependent …

An Intronic Picalm Polymorphism, Rs588076, Is Associated With Allelic Expression Of A Picalm Isoform, Ishita Parikh, Christopher Medway, Steven Younkin, David Fardo, Steven Estus

Physiology Faculty Publications

BACKGROUND: Although genome wide studies have associated single nucleotide polymorphisms (SNP)s near PICALM with Alzheimer's disease (AD), the mechanism underlying this association is unclear. PICALM is involved in clathrin-mediated endocytosis and modulates Aß clearance in vitro. Comparing allelic expression provides the means to detect cis-acting regulatory polymorphisms. Thus, we evaluated whether PICALM showed allele expression imbalance (AEI) and whether this imbalance was associated with the AD-associated polymorphism, rs3851179.

RESULTS: We measured PICALM allelic expression in 42 human brain samples by using next-generation sequencing. Overall, PICALM demonstrated equal allelic expression with no detectable influence by rs3851179. A single sample demonstrated …

Translation Initiation Rate Determines The Impact Of Ribosome Stalling On Bacterial Protein Synthesis, Steven J. Hersch, Sara Elgamal, Assaf Katz, Michael Ibba, William Wiley Navarre

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ribosome stalling during translation can be caused by a number of characterized mechanisms. However, the impact of elongation stalls on protein levels is variable, and the reasons for this are often unclear. To investigate this relationship, we examined the bacterial translation elongation factor P (EF-P), which plays a critical role in rescuing ribosomes stalled at specific amino acid sequences including polyproline motifs. In previous proteomic analyses of both Salmonella and Escherichia coli efp mutants, it was evident that not all proteins containing a polyproline motif were dependent on EF-P for efficient expression in vivo . The α- and β-subunits of …

Ef-P Dependent Pauses Integrate Proximal And Distal Signals During Translation, Sara Elgamal, Assaf Katz, Steven J. Hersch, David Newsom, Peter White, William Wiley Navarre, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is required for the efficient synthesis of proteins with stretches of consecutive prolines and other motifs that would otherwise lead to ribosome pausing. However, previous reports also demonstrated that levels of most diprolyl-containing proteins are not altered by the deletion of efp. To define the particular sequences that trigger ribosome stalling at diprolyl (PPX) motifs, we used ribosome profiling to monitor global ribosome occupancy in Escherichia coli strains lacking EF-P. Only 2.8% of PPX motifs caused significant ribosomal pausing in the Δefp strain, with up to a 45-fold increase in ribosome density observed at …

The Effect Of Maternal Aldosterone Levels On The Expression Of 11b-Hsd Isoenzymes In Normal And Hypertensive Rat Placentae, Nicole Jorissen

Journal of Undergraduate Research at Minnesota State University, Mankato

In this project, we developed a Western blotting procedure to semi-quantitate levels of 11β-HSD1 and 11β-HSD2 in whole cell extracts. Then, we applied this technique to analyze the effect of reduced maternal aldosterone levels on the expression of 11β-HSD1 and 11β-HSD2 isoenzymes in the placental tissue in both normal and hypertensive rats. These enzymes control levels of glucocorticoids which compete for aldosterone’s mineralocorticoid receptor. Overstimulation of this receptor results in hypertension. If aldosterone levels decrease, levels of the enzymes controlling active glucocorticoid concentrations might change to compensate for the lowered aldosterone levels. Decreased placental 11β-HSD2 expression could affect hypertension in …

Cryopreservation Of Hepatocyte (Hepg2) Cell Monolayers: Impact Of Trehalose, Blake Stokich, Quinn Osgood, David Grimm, Shhyam Moorthy, Nilay Chakraborty, Michael A. Menze

Faculty Research & Creative Activity

A simple method to cryogenically preserve hepatocyte monolayers is currently not available but such a technique would facilitate numerous applications in the field of biomedical engineering, cell line development, and drug screening. We investigated the effect of trehalose and dimethyl sulfoxide (Me2SO) in cryopreservation of human hepatocellular carcinoma (HepG2) cells in suspension and monolayer formats. HepG2 cell monolayers were incubated for 24 h at varying concentrations of trehalose (50–150 mM) prior to cryopreservation to identify the optimum concentration for such preincubation. When trehalose alone was used as the cryoprotective agent (CPA), cells in monolayer format did not survive freezing while …

Cryopreservation Of Hepatocyte (Hepg2) Cell Monolayers: Impact Of Trehalose, Blake Stokich, Quinn Osgood, David Grimm, Shhyam Moorthy, Nilay Chakraborty, Michael Menze

Faculty and Staff Scholarship

A simple method to cryogenically preserve hepatocyte monolayers is currently not available but such a technique would facilitate numerous applications in the field of biomedical engineering, cell line development, and drug screening. We investigated the effect of trehalose and dimethyl sulfoxide (Me2SO) in cryopreservation of human hepatocellular carcinoma (HepG2) cells in suspension and monolayer formats. HepG2 cell monolayers were incubated for 24 h at varying concentrations of trehalose (50–150 mM) prior to cryopreservation to identify the optimum concentration for such preincubation. When trehalose alone was used as the cryoprotective agent (CPA), cells in monolayer format did not survive freezing while …

Melanin As An Oto-Protective Pigment In Two Fish Species: Poecilia Latipinna And Cyprinus Carpio , Bethany N. Coffey

Masters Theses & Specialist Projects

Melanin is the dark pigment found in most organisms that gives color to the skin, hair, feathers, and eyes of vertebrates. While melanin is known to also be present in the stria vascularis of the mammalian cochlea, its function in the inner ear is still unknown. Some previous studies have indicated that melanin may serve to protect the mammalian ear from hearing loss. Minimal previous research on melanin within the inner ears of fishes has been conducted. In this study, the melanin levels in the inner ears of different color morphs of two fish species (Poecilia latipinna and Cyprinus …

Physiological Effects Of A Kettlebell Workout Versus A High-Resistance Circuit Workout, Brett Schreiber

Graduate Theses and Dissertations

Purpose: To compare the physiological effects of a single kettlebell workout to a high-resistance circuit workout in resistance-trained males. Methods: 12 resistance trained healthy males (age: 24 ± 2.97 years; height: 1.75 ± 0.064 m; body mass: 75.99 ± 8.46 kg) participated in this study. Participants had a familiarization visit and two subsequent experimental visits (kettlebell workout; circuit workout). The kettlebell workout consisted of 12-minutes of standardized kettlebell swings. The circuit workout consisted of three sets of 6 repetitions of smith machine squats, bench press, leg curl, and lat pulldown. Heart rate, rectal temperature, skin temperature, blood lactate, rating of …

Mirna-21 Has Anti-Inflammatory Effects In The Macrophage Response To Peritonitis., Rebecca Elise Barnett

Electronic Theses and Dissertations

This project investigated the role of miRNA-21 in the macrophage response to peritonitis; with the goal of understanding whether the associated mechanism has potential benefits in the clinical treatment of peritonitis. A novel therapeutic intervention in the treatment of peritonitis could modulate the host immune response to decrease an exaggerated pro-inflammatory innate response and then prevent or ameliorate the development of sepsis and organ failure. We found the following: 1. MiRNA-21 expression increases in peritoneal macrophages after lipopolysaccharide (LPS) stimulation. 2. Over expression of miRNA-21 decreases TNF-a secretion from macrophages after LPS stimulation. Suppression of miRNA-21 expression results in increased …

Balance And Power In Older Adults With And Without A History Of Falls, Stephanie Michelle Gray

Graduate Theses and Dissertations

The purpose of this study was to observe the differences between power and balance in older adults over the age of 65 with and without falls. A total of 62 community dwelling older adults between the ages of 65 and 92 participated in the study. Two groups consisted of 25 fallers and 37 non-fallers. No statistical differences were found between groups on age, height, weight, or BMI. Testing included the Berg Balance Scale (BBS) to test balance, the Tendo Weightlifting Analyzer (TWA) during a sit-to-stand to test lower body power, and the Physical Activity Scale for the Elderly (PASE) to …

The Effect Of Leucine Supplementation On Biomarkers Of Mitochondrial Biogenesis And Protein Synthesis In Soleus Muscle Of Rats Fed A High-Fat Diet, Gina Davis

Graduate Theses and Dissertations

Mitochondrial dysfunction is a contributing factor to the advancement of various diseases including obesity, diabetes, and cardiovascular disease. Impairment in mitochondria brings about a diminished mitochondrial number and oxidative capacity. Leucine is known to stimulate muscle protein synthesis through transcription and translation of nuclear DNA leading to increases in mitochondrial biogenesis and fatty acid oxidation. However, the effects of leucine on anabolic factors of the mitochondrial genome, during catabolic conditions are not known. PURPOSE: To determine if leucine supplementation alters the negative effects of a high fat (60%) diet (HFD) on the mitochondrial genome by measuring the gene expression of …

Effects Of Breathing Cool Air During Cycling Exercise In The Heat, Christian B. Ridings

Graduate Theses and Dissertations

INTRODUCTION: The purpose of this study was to establish the ability of the Core Cooler device to prevent rises in physiological heat strain of trained male cyclists during cycling exercise in the heat. METHODS: 15 healthy male cyclists cycled at 50-70% VO2max for 75 minutes in a heat chamber of 31°C & 55% RH while breathing through the Core Cooler device under three different conditions: 1:4 ratio without ice termed control (CN), 1:4 ratio with ice termed low intermittent (LI), and at 1:1 ratio with ice termed high intermittent (HI). Data collected every 15 minutes assessing intestinal temperature (TGI), heart …