Physiology Commons^™

The International Journal Of Exercise Science: 2011 Year In Review, T. Scott Lyons, Jenny Hutchens, James W. Navalta

International Journal of Exercise Science

The International Journal of Exercise Science: 2011 Year in Review

Roles Of Trna In Cell Wall Biosynthesis, Kiley Dare, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Recent research into various aspects of bacterial metabolism such as cell wall and antibiotic synthesis, degradation pathways, cellular stress, and amino acid biosynthesis has elucidated roles of aminoacyl‐transfer ribonucleic acid (aa‐tRNA) outside of translation. Although the two enzyme families responsible for cell wall modifications, aminoacyl‐phosphatidylglycerol synthases (aaPGSs) and Fem, were discovered some time ago, they have recently become of intense interest for their roles in the antimicrobial resistance of pathogenic microorganisms. The addition of positively charged amino acids to phosphatidylglycerol (PG) by aaPGSs neutralizes the lipid bilayer making the bacteria less susceptible to positively charged antimicrobial agents. Fem transferases utilize …

The Effects Of Oxygen On The Electrophysiology Of Co2/H+-Chemosensitive And -Insensitive Neurons Of The Solitary Complex Of The Rat, Michael Patrick Matott

USF Tampa Graduate Theses and Dissertations

This study tested the hypothesis that decreasing the control O₂ level from 95% to 40% (5% CO₂ + 55% N₂) maintains viability in caudal solitary complex (cSC) neurons in transverse slices (~300-400ꝳ) prepared from neonatal rat (P2-22) maintained at 32-34°C. The underlying rationale is to reduce exposure to redox and nitrosative stimuli generated during several hours of exposure to 95% O₂ that produces a tissue O₂ tension throughout the slice which is in excess of 203 kPa (2.0 atmospheres absolute,ATA) oxygen. Whole cell recordings of cSC neurons maintained in 40% O₂ exhibited spontaneous …

High Altitude Diving In River Otters: Coping With Combined Hypoxic Stresses, Jamie R. Crait, Henry D. Prange, Noah A. Marshall, Henry J. Harlow, Clark Cotton, Merav Ben-David

Biology Faculty Publications

River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of elevations and represent an appropriate model for assessing the physiological responses to diving at altitude. In this study, we performed blood gas analyses and compared blood chemistry of river otters from a high-elevation (2357 m) population at Yellowstone Lake with a sea-level population along the Pacific coast. Comparisons of oxygen dissociation curves (ODC) revealed no significant difference in hemoglobin-oxygen (Hb-O₂) binding affinity between the two populations - potentially because of demands for tissue oxygenation. Instead, high-elevation otters had greater Hb concentrations (18.7 …

Two-Dimensional Blood Flow Velocity Estimation Using Apparent Speckle Pattern Angle Dependence On Scan Velocity, Tiantian Xu, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

An algorithm which measures the lateral component of blood flow velocity was developed in our previous studies based on the increase in speckle size due to relative motion between moving scatterers and spatial rate of scanner A-line acquisition (scan velocity). In this paper, the apparent dominant angle of the speckle pattern in a straight vessel was investigated and a new method of two-dimensional blood flow velocity estimation is introduced. Different scan velocities were used for data acquisition from blood flow traveling at an angle relative to the ultrasound beam. The apparent angle of the speckle pattern changes with different scan …

Monitoring Cerebral Hemodynamics With Transcranial Doppler Ultrasound During Cognitive And Exercise Testing In Adults Following Unilateral Stroke, Brian P. Watt, Judith M. Burnfield, Edward J. Truemper, Thad W. Buster, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

An observational study was performed as a preliminary investigation into the use of transcranial Doppler ultrasound (TCD) for recording cerebral hemodynamic changes during multiple tasks. TCD is a method of measuring cerebral blood flow (CBF) using ultrasound transducers in contact with the surface of the head. Using the maximum flow envelope of the Doppler spectrum returning from the middle cerebral artery (MCA), standard clinical flow indices can be calculated and displayed in real time providing information concerning perturbations in CBF and their potential cause. These indices as well as flow velocity measurements have been recognized as useful in measuring changes …

Dynamic Variability Of Isometric Action Tremor In Precision Pinching, Tim Eakin, Waneen Spirduso, Karen Francis

Kinesiology (Formerly Exercise and Sport Science)

Evolutionary development of isometric force impulse frequencies, power, and the directional concordance of changes in oscillatory tremor during performance of a two-digit force regulation task was examined. Analyses compared a patient group having tremor confounding volitional force regulation with a control group having no neuropathological diagnosis. Dependent variables for tremor varied temporally and spatially, both within individual trials and across trials, across individuals, across groups, and between digits. Particularly striking findings were magnitude increases during approaches to cue markers and shifts in the concordance phase from pinching toward rigid sway patterns as the magnitude increased. Magnitudes were significantly different among …

Notes On The Diet Of The Malay Civet (Viverra Tangalunga) And Other Civets In Logged And Unlogged Lowland Dipterocarp Rain Forests In Sabah, Borneo, Christina P. Colon, John B. Sugau

Publications and Research

Civet diets were examined in a logged and unlogged Bornean rain forest. Malay civets (Viverra tangalunga) consumed invertebrates, fruit, rodents, insectivores, birds, snakes and lizards, and appear to show preference for centipedes and scorpions. Other civet species consumed fruit, such as figs, Connarus sp. and Annona sp., particularly in the unlogged forest, but also consumed invertebrates and vertebrates. Reduced fruit consumption observed in the logged forest may be due to lower availability and may be offset by increased consumption of invertebrates. The increased overlap in diet between Malay civets and other civets in disturbed areas may lead to …

An Eccentric Intervention Of The Flexor-Pronator Mass To Impact Overhead Throwing Distance And Velocity, Ricker Stanton Adkins

Online Theses and Dissertations

This study focused on the pronator-flexor mass of the elbow and its role in the overhead throwing motion. This specific muscle group is responsible for primary pronation and flexion at the elbow joint, while also reducing valgus stress from compromising the ulnar collateral ligament.

Twenty-three participants were put through a short throwing progression that was focused on their velocity and overall distance thrown from a standing position. After baseline testing was completed participants underwent a short intervention to determine if the intervention would impact all dependent variables. Experimental and non-experimental groups were compared using a repeated measures ANOVA which found …

A Computational Study Of The Vibrational Behavior Of Fluid-Filled Spherical Thin Shells, Sami Abdul-Wahid

Undergraduate Honors Theses

Three-dimensional finite-element modeling of the resonance behavior of thin spherical shells is done with the COMSOL multi-physics software package and comparisons are made with experimental data and theoretical predictions. Computational models of the sell in vacuo, and with water inside, are tested. Results in vacuo show a 1% agreement in the very thin shell (h/R=1/250, for thickness h and radius R). Three experimentally measured resonance frequencies below 8500 Hz of the water filled shell are predicted computationally to within 25 Hz. Other spectral similarities and discrepancies are discussed qualitatively. The data suggests that the COMSOL …

Effects Of Self-Directed Physiological Monitoring On Therapists Anxiety, Melissa D. Dalton

Theses and Dissertations--Family Sciences

This mixed-method study investigated the effects of self-directed physiological monitoring on therapists anxiety. Ten therapists participated in a10-week physiological monitoring training sessions while monitoring respiratory sinus arrhythmia (RSA) and heart rate variability (HRV). The participants completed the state-trait anxiety inventory questionnaire after having a first, sixth, or tenth therapy session with a client. This was designed to monitor their state anxiety while working with clients. A series of paired sampled t-tests was conducted to assess changes in HRV, RSA, trait anxiety, and state anxiety. One significant result was found: the RSA of the therapist increased significantly. Correlations existed between …

Salinity Preference Of Alaskan Threespine Stickleback: Test For Divergence In Halotaxis Between Ancestral And Landlocked Populations, David Fryxell, Eric T. Schultz

EEB Articles

Glacial retreat during the Pleistocene caused landlocking of anadromous Alaskan threespine stickleback, Gasterosteus aculeatus, furnishing a natural ‘experiment’ in osmoregulatory divergence. The objective of this study was to assess the effects of individual acclimation and population divergence on salinity preference. Full-sibling families of marine, anadromous, and freshwater-landlocked populations of stickleback were reared in common environments until 3 weeks post-hatch, then were split and acclimated to low or high salinity. At 6 to 8 weeks of age the six experimental groups were tested for salinity preference in a tank that offers fish a choice of compartments with different salinities arranged …

Serine 910 Phosphorylation Of Focal Adhesion Kinase Is Critical For Costamere Assembly, Miensheng Chu

Dissertations

Tyrosine-phosphorylated FAK is required for the hypertrophic response of cardiomyocytes to growth factors and mechanical load, but the role of FAK serine phosphorylation in this process is unknown. Endothelin-1 (ET-1; 1-100nM, 2-30min) and other hypertrophic factors induced a time- and dose-dependent increase in FAK-S910 phosphorylation in neonatal rat ventricular myocytes (NRVM). FAK-S910 phosphorylation required ET_AR-dependent activation of PKCδ and Src via parallel Raf-1→MEK1/2→ERK1/2 and MEK5→ERK5 signaling pathways. Using co-immunoprecipitation, TIRF-microscopy and FRAP, ET-1 stimulation of NRVM expressing a nonphosphorylatable, S910A-FAK mutant decreased the interaction of paxillin and vinculin within costameres. This interaction was important in stabilizing α-actinin within …

An Investigation Of The Phospholamban-Serca Regulatory Interaction With Fluorescence Resonance Energy Transfer, Philip Adam Bidwell

Dissertations

With Fluorescence Resonance Energy Transfer (FRET), we are able to detect changes in the structure and affinity of the PLB-SERCA regulatory complex in live cells. Using this approach, we have detected a high level of PLB-SERCA interaction even at Ca2+ concentrations known to fully relieve PLB inhibition of SERCA, suggesting that dissociation is not required for relief of inhibition. We also detect no real-time change in PLB-SERCA binding over the course of a single Ca2+ transient in paced myocytes. The effect of Ca2+ on the PLB-SERCA interaction is best described as a reduced affinity with no change in the structure …

Receptor-Mediated Hypertrophic Signaling Via Protein Kinase D And Histone Deacetylase 5 In Adult Myocytes, Chia-Wei Jenny Chang

Dissertations

Hemodynamic stress and neurohumoral signaling are common causes of cardiac hypertrophy. These extrinsic stress stimuli typically act on GPCR and induce a cascade of signal transduction to re-program terminally differentiated myocytes to grow in length or width. The compensatory hypertrophic response can enhance cardiac output briefly due to increased work load. However, prolonged stress results in maladaptive changes in the heart and gradually deteriorates ventricular function to supply blood throughout the body. Sustained hypertrophic signaling can also progress toward heart failure.

My dissertation research focuses on the hypertrophic signaling in adult cardiac myocytes in response to neurohumoral stimuli, ET-1 and …

Electric Field Exposure Triggers And Guides Formation Of Pseudopod-Like Blebs In U937 Monocytes, Mikhail A. Rassokhin, Andrei G. Pakhomov

Bioelectrics Publications

We describe a new phenomenon of anodotropic pseudopod-like blebbing in U937 cells stimulated by nanosecond pulsed electric field (nsPEF). In contrast to "regular," round-shaped blebs, which are often seen in response to cell damage, pseudopod-like blebs (PLBs) formed as longitudinal membrane protrusions toward anode. PLB length could exceed the cell diameter in 2 min of exposure to 60-ns, 10-kV/cm pulses delivered at 10-20 Hz. Both PLBs and round-shaped nsPEF-induced blebs could be efficiently inhibited by partial isosmotic replacement of bath NaCl for a larger solute (sucrose), thereby pointing to the colloid-osmotic water uptake as the principal driving force for bleb …

Mrna Granules And Ischemic Preconditioning, Michelle Rei Smith

Wayne State University Theses

Brain ischemia and reperfusion that occurs after stroke and cardiac arrest, causes translation arrest (TA) in neurons which is irreversible in neurons that will undergo delayed neuronal death. TA is linked to mRNA granules, which are involved in ischemia-induced stress genes translation. Ischemic preconditioning (IPC) is the most protective response known that protects neurons from a lethal ischemic insult. In this thesis I studied the effects of (1) sublethal durations of ischemia, (2) IPC and (3) cycloheximide (CHX) on the formation of mRNA granules at 1 hour of reperfusion and the colocalization of HuR in the mRNA granules. All durations …

Foraging And Roosting Behaviors Of Rafinesque's Big-Eared Bat (Corynorhinus Rafinesquii) At The Northern Edge Of The Species Range, Joseph S. Johnson

Theses and Dissertations--Animal and Food Sciences

Bat populations in the eastern United States are currently declining at unprecedented rates as a result of habitat loss, commercial wind energy development, and white-nose syndrome. Effective conservation of these declining populations requires knowledge of several aspects of summer and winter ecology, including daytime habitat use (day-roost selection and social behaviors), nocturnal habitat use (foraging habitat selection, prey selection, and prey abundance), and winter hibernation (torpor) patterns. This dissertation addresses these questions for Rafinesque’s big-eared bat (Corynorhinus rafinesquii), a species of conservation concern in the southeastern United States. Kentucky represents the northern edge of the range of Rafinesque’s …

Body Mass Bias In Exercise Physiology, Paul M. Vanderburgh

Health and Sport Science Faculty Publications

In certain physically demanding occupations, especially the military, body mass bias has substantive implications. Work physiologists have determined that despite body mass bias in the common military physical fitness tests, the larger service members were often better performers of the physically demanding occupational tasks (Bilzon et al., 2002; Lyons et al., 2005; Rayson et al., 2000). That is, they could carry more, more easily evacuate casualties, and better engage in heavy materiel handling. Yet, the smaller personnel were achieving better scores on the physical fitness tests, the results of which have significant promotion and advancement implications (Vanderburgh & Mahar , …

The Cardiac L-Type Calcium Channel Distal Carboxyl- Terminus Auto-Inhibition Is Regulated By Calcium, Shawn M. Crump

Theses and Dissertations--Physiology

The L-type calcium channel (LTCC) provides trigger Ca²⁺ for sarcoplasmic reticulum Ca²⁺-release and LTCC function is influenced by interacting proteins including the LTCC Distal Carboxyl-terminus (DCT) and calmodulin. DCT is proteolytically cleaved, and re-associates with the LTCC complex to regulate calcium channel function. DCT reduces LTCC barium current (IBa,L) in reconstituted channel complexes, yet the contribution of DCT to ICa,L in cardiomyocyte systems is unexplored. This study tests the hypothesis that DCT attenuates cardiomyocyte ICa,L. We measured LTCC current and Ca²⁺ transients with DCT co-expressed in murine cardiomyocytes. We also heterologously co-expressed DCT and CaV1.2 constructs …