Physiology Commons^™

Fgf4 Induced Wnt5a Gradient In The Limb Bud Mediates Mesenchymal Cell Directed Migration And Division, John C. Allen

Theses and Dissertations

The AER has a vital role in directing embryonic limb development. Several models have been developed that attempt to explain how the AER directs limb development, but none of them are fully supported by existing data. I provide evidence that FGFs secreted from the AER induce a gradient of Wnt5a. I also demonstrate that limb mesenchyme grows toward increasing concentrations of Wnt5a. We hypothesize that the changing shape of the AER is critical for patterning the limb along the proximal to distal axis. To better understand the pathway through which Wnt5a elicits its effects, we have performed various genetic studies. …

Caveolins And Njks Influence Brain Endothelial Permeability After Juvenile Tbi, David Olufemi Ajao

Loma Linda University Electronic Theses, Dissertations & Projects

Disruption of blood-brain barrier (BBB) is a key secondary event that exacerbates brain damage following traumatic brain injury (TBI). BBB disruption is particularly damaging to the developing brain – which is highly vulnerable to various stress stimuli, resulting in increased brain swelling, disrupted cerebral blood flow (CBF) autoregulation, long-term disabilities and death following TBI in young demographic. Unsurprisingly, BBB disruption and the resultant cerebral edema have emerged as therapeutic targets in juvenile TBI. It is therefore important to understand the molecular players and mechanisms involved in TBI-induced BBB disruption in the juvenile brain. To this end, the endothelial caveolins and …

Variability Of Practice And Strength Training Periodization: When Theories Collide, Katherine Lauren Streder

Master's Theses

The primary purpose of this study was to examine whether variability of practice enhances neuromuscular adaptations when compared to traditional strength training. The secondary purpose was to investigate whether there was a difference in perception of exertion between the two strength programs. Forty one subjects (23 women and 18 men) were assigned to either the control group or one of two treatment groups by a blocked-random method. Subject's one repetition maximum (1RM) for the kettlebell press and leg press were measured at baseline, after 4 weeks of training, and after 8 weeks of training. The treatment groups completed 8 weeks …

Comparison Of Theophylline And 8-Cyclopentyltheophylline On The Heart Rates Of Neonatal Rats, Stephanie Arnold

Undergraduate Honors Theses

Neonatal apnea is a serious condition that affects the health of infants, especially those born prematurely. To stimulate breathing, methylxanthine drugs, such as theophylline and caffeine, are administered to reverse this condition in humans and avoid the use of breathing-assistance equipment. These drugs cause stimulation of the central nervous system and the heart, however, both detrimental side effects in preterm infants. Antagonism of adenosine receptors is the proposed mechanism of methylxanthine action. Synthetic chemists have produced xanthine analogs with increased affinity for adenosine receptors that could lead to respiratory stimulation while reducing cardiostimulant effects. For this study, theophylline and 8-cyclopentyltheophylline …

A Test Of Whether Human Handling Causes Developmental Or Habituation Effects On The Hypothalamic-Pituitary-Adrenal Stress Response Of Young American Kestrels (Falco Sparverius), Erin Leigh Wonder

Boise State University Theses and Dissertations

Early exposure to stressors affects subsequent stress responses in both mammalian and avian species, with the likelihood for lasting effects depending, in part, on the magnitude of the stressor. However, it is unclear whether lasting effects are the result of developmental changes to the hypothalamic-pituitary-adrenal (HPA) axis or habituation to the stressor. I investigated the effects of human handling, a known stressor, in free-living American kestrel (Falco sparverius) nestlings to determine if this brief, non-invasive stressor causes lasting changes in the stress response of handled birds, and whether alterations in the stress response were the result of developmental …

Endocannabinoid-Dependent Long-Term Depression Of Ventral Tegmental Area Gaba Neurons, Jared Mark Weed

Theses and Dissertations

GABA neurons in the ventral tegmental area of the midbrain are important components in the brain's reward circuit. Long term changes in this circuit occur through the process of synaptic plasticity. It has been shown that high frequency stimulation, as well as treatment with endocannabinoids, can cause GABA neurons in the ventral tegmental area to undergo long term depression, a form of synaptic plasticity that decreases excitability of cells. The present study elaborates on the mechanism whereby high frequency stimulation can result in long term depression of ventral tegmental area GABA neurons. Using the whole cell patch clamp technique in …

The Efficacy Of Partial Squats On Measures Of Strength And Explosiveness: An Exploratory Study, Caleb D. Bazyler, Kimitake Sato, Craig A. Wassinger, Hugh S. Lamont, Michael H. Stone

ETSU Faculty Works

Abstract available in the 8th Annual Coaches and Sport Science College.

Differential Effects Of Short-Chain Fatty Acids On Motility Of Guinea Pig Proximal And Distal Colon, Norman Hurst

Theses and Dissertations

NTRODUCTION: Colonic bacteria produce short-chain fatty acids (SCFAs) by fermentation of dietary carbohydrates and fiber. The production of SCFAs is greatest in proximal colon where propulsion is likely to be highly dependent on chemical/nutrient stimuli. Unabsorbed SCFAs entering the distal colon are likely to modify peristalsis initiated by fecal pellet-induced distension. AIM: To determine the effect of individual SCFAs on propulsive contractions in guinea pig proximal colon and on pellet propulsion in distal colon. METHODS: Proximal colon was excised, cannulated and placed in Krebs buffer in an organ bath. After equilibration, the colon was distended with 1ml of Krebs buffer …

Molecular Events In The Cell Types Of The Olfactory Epithelium During Adult Neurogenesis, Paula M. Heron, Arnold J. Stromberg, Patrick Breheny, Timothy S. Mcclintock

Physiology Faculty Publications

BACKGROUND: Adult neurogenesis, fundamental for cellular homeostasis in the mammalian olfactory epithelium, requires major shifts in gene expression to produce mature olfactory sensory neurons (OSNs) from multipotent progenitor cells. To understand these dynamic events requires identifying not only the genes involved but also the cell types that express each gene. Only then can the interrelationships of the encoded proteins reveal the sequences of molecular events that control the plasticity of the adult olfactory epithelium.

RESULTS: Of 4,057 differentially abundant mRNAs at 5 days after lesion-induced OSN replacement in adult mice, 2,334 were decreased mRNAs expressed by mature OSNs. Of the …

Modeling Dipyrenylpropane, Steven Bray, David Busath

Journal of Undergraduate Research

1,3-di(1-pyrenyl)propane(hereinafter dipyrenylpropane) has proven very useful as a fluorescence probe in determining fluidity and monitoring phase transitions in biological membrane systems.1 By virtue of its structure, dipyrenylpropane may fluoresce light in an excimer or a monomer configuration. Each configuration fluoresces light at a different wavelength, thus allowing us to monitor the excimer-to-monomer intensity ratio. The excimer form occurs when, as the light is absorbed, the pyrene branches come within close proximity, transferring energy and fluorescing light back at a different wavelength.2 The monomer configuration is defined by the lack of energy transfer and a consistent fluorescence wavelength. Therefore, as membrane …

Phylogeny Of Siphonaptera In Relation To Mecoptera And The Snow Fleas Using Molecular Data From The Mitochondrial Gene Cytochrome Oxidase Ii, Sonia Bake, Dr. Michael Whiting

Journal of Undergraduate Research

The intent of this study is to determine the phylogeny of the order Siphonaptera (fleas) and their relationship to the order Mecoptera (scorpion flies) including the Boreidae family (snow fleas) which have traditionally been placed with the scorpion flies. A study is being conducted using molecular data from several genes and morphology to design a more accurate phylogeny for these orders. This study uses the data from a single gene, cytochrome oxidase II or COII, to create a tree for several species from these orders.

The Composite Effect For Inverted Faces Is Reliable At Large Sample Sizes And Requires The Basic Face Configuration, Tirta Susilo, Constantin Rezlescu, Bradley Duchaine

Dartmouth Scholarship

Abstract The absence of the face composite effect (FCE) for inverted faces is often considered evidence that holistic processing operates only on upright faces. However, such absence might be explained by power issues: Most studies that have failed to find the inverted FCE tested 24 participants or less. Here we find that the inverted FCE exists reliably when we tested at least 60 participants. The inverted FCE was ∼ 18% the size of the upright FCE, and it was unaffected by testing order: It did not matter whether participants did the upright condition first (Experiment 1, n = 64) or …

Validity Of Boston Marathon Qualifying Times, Paul M. Vanderburgh

Health and Sport Science Faculty Publications

Purpose: To assess the validity of Boston Marathon qualifying (BMQ) standards for men and women. Methods: Percent differences between BMQ and current world records (WR) by sex and age group were computed. WR was chosen as the criterion comparison because it is not confounded by intensity, body composition, lifestyle, or environmental factors. A consistent difference across age groups would indicate an appropriate slope of the age-vs-BMQ curve. Inconsistent differences were corrected by adjusting BMQ standards to achieve a uniform percentage difference from WR. Results: BMQ standards for men were consistently ~50% slower than WR (mean 51.5% ± …

Insulin Responsiveness In Metabolic Syndrome After Eight Weeks Of Cycle Training, Charles A. Stuart, Mark A. South, Michelle L. Lee, Melanie P. Mccurry, Mary E. A. Howell, Michael W. Ramsey, Michael H. Stone

ETSU Faculty Works

Introduction Insulin resistance in obesity is decreased after successful diet and exercise. Aerobic exercise training alone was evaluated as an intervention in subjects with the metabolic syndrome.

Methods Eighteen nondiabetic, sedentary subjects, 11 with the metabolic syndrome, participated in 8 wk of increasing intensity stationary cycle training.

Results Cycle training without weight loss did not change insulin resistance in metabolic syndrome subjects or sedentary control subjects. Maximal oxygen consumption (V˙O2max), activated muscle AMP-dependent kinase, and muscle mitochondrial marker ATP synthase all increased. Strength, lean body mass, and fat mass did not change. The activated mammalian target of rapamycin was not …

Carbohydrate Mouth Rinse Improves 1.5 H Run Performance: Is There A Dose-Effect?, Benjamin F. Wright, Glen Davison

International Journal of Exercise Science

International Journal of Exercise Science 6(4) : 328-340, 2013. There is a substantial body of recent evidence showing ergogenic effects of carbohydrate (CHO) mouth rinsing on endurance performance. However, there is a lack of research on the dose-effect and the aim of this study was to investigate the effect of two different concentrations (6% and 12% weight/volume, w/v) on 90 minute treadmill running performance. Seven active males took part in one familiarization trial and three experimental trials (90-minute self-paced performance trials). Solutions (placebo, 6% or 12% CHO-electrolyte solution, CHO-E) were rinsed in the mouth at the beginning, and at 15, …

The Influence Of Start Position, Initial Step Type, And Usage Of A Focal Point On Sprinting Performance, Jennifer L. Dysterheft, William J. Lewinski, Dawn A. Seefeldt, Robert W. Pettitt

International Journal of Exercise Science

International Journal of Exercise Science 6(4) : 320-327, 2013. For many athletes, sprinting acceleration is vital to sport performance. The purpose of this study was to observe the influences of starting position, type of initial step taken, and a focal point on sprinting velocity, stride length, and acceleration over a 9.1 m distance. Two trials of four conditions were video recorded in which subjects had no focal point (n = 10) or a lateral focal point (n ₌ 9). The four conditions were: forwards (control), backwards, 90° left (90°L), and 90° right (90°R). Lower velocities (p > 0.05) were …

Evaluating Acute Changes In Joint Range-Of-Motion Using Self-Myofascial Release, Postural Alignment Exercises, And Static Stretches, Derek S. Roylance, James D. George, Adam M. Hammer, Nicole Rencher, Gilbert W. Fellingham, Ronald L. Hager, William J. Myrer

International Journal of Exercise Science

International Journal of Exercise Science 6(4) : 310-319, 2013. This study was designed to compare the acute effect of self-myofascial release (SMR), postural alignment exercises, and static stretching on joint range-of-motion. Our sample included 27 participants (n = 14 males and n = 13 females) who had below average joint range-of-motion (specifically a sit-and-reach score of 13.5 inches [34.3 cm] or less). All were university students 18–27 years randomly assigned to complete two 30–40-minute data collection sessions with each testing session consisting of three sit-and-reach measurements (which involved lumbar spinal flexion, hip flexion, knee extension, and ankle dorsiflexion) interspersed with …

Increasing The Distance Of An External Focus Of Attention Has Limited Effects On Standing Long Jump Performance, William Westphal, Jared M. Porter

International Journal of Exercise Science

International Journal of Exercise Science 6(4) : 300-309, 2013. Several previous studied have demonstrated that adopting an external focus of attention (i.e., directing attention towards the result of the movement) improves the performance of a variety of motor skills. The objective of this study was to investigate if increasing the distance of an external focus of attention would further improve standing long jump performance. We hypothesized that as the distance of the external focus increased so would jumping distance. We also hypothesized that when subjects completed jumps in the external focus of attention conditions they would jump significantly further than …

Biomechanical And Proprioceptive Differences During Drop Landings Between Dancers And Non-Dancers, Katie E. Volkerding, Caroline J. Ketcham Ph.D.

International Journal of Exercise Science

International Journal of Exercise Science 6(4) : 289-299, 2013. The focus of this research was to determine if female dancers have differing kinematic and kinetic characteristics when landing from three heights (0.2, 0.5, and 0.8 m) both with and without vision compared to non-dancers. It was hypothesized that dancers would show differing kinematic and kinetic patterns of control due to their increased proprioceptive awareness. Eight collegiate dancers and seven collegiate controls who were neither dancers nor collegiate jumping athletes volunteered for this study. Sagittal plane lower limb joint angles were measured at 100 Hz prior to landing through stability with …

Upper Body Muscular Activation During Variations Of Push-Ups In Healthy Men, Caroline C. Allen, Katie A. Dean, Alan P. Jung, John K. Petrella

International Journal of Exercise Science

International Journal of Exercise Science 6(4) : 278-288, 2013. The purpose of this study was to assess neural activity for upper body musculature in college-age men during repetitions of a conventional pushup or a Perfect Pushup^TM. Eighteen healthy men (21.6±1 yr, 182.5±7 cm, 87.4±15 kg) completed five repetitions of a conventional pushup and Perfect Pushup^TM while using a wide hand base of support for the upper body. Body position, hand placement, and cadence of the pushup were standardized. Root mean square electromyography (RMS-EMG, mV/Sec) was collected for the triceps brachii (TB), pectoralis major (PM), serratus anterior (SA), …