Physiology Commons^™

Changes In Intragastric Temperature Reflect Changes In Heat Stress Following Tepid Fluid Ingestion But Not Ice Slurry Ingestion, Christopher J. Stevens, Ben Dascombe

Journal of Human Performance in Extreme Environments

This study examined the effects of fluid and ice slurry ingestion on the relationship between intragastric temperature and rectal temperature in humans during physical activity. The purpose was to identify a technique to quantify changes in heat stress in situations when temperature probes are not feasible and when time constraints do not allow for a period long enough for an indigestible temperature capsule to reach the lower gastrointestinal tract. Eight moderately trained male runners inserted a rectal probe and ingested a telemetric capsule before randomized, crossover, pre-exercise ingestion of 7.5 mL x kg^-1 x BM^-1tepid fluid (22°C) …

Effects Of Prenatal Environment Are Revealed By Post-Natal Challenges: Embryonic Hormone Exposure, Adrenocortical Function And Food In Seabird Chicks, Z. Morgan Benowitz-Fredericks, Jannik Schultner, Alexander S. Kitaysky

Faculty Journal Articles

The interaction between prenatal environments and postnatal environments is an important source of phenotypic variability. We examined the ability of prenatal steroid exposure and postnatal energy restriction to explain adrenocortical function and fledging age in captive seabird chicks. We proposed and tested two hypotheses: (1) the strength of prenatal effects is attenuated by challenging postnatal environments (postnatal override) and (2) the strength of prenatal effects increases with the severity of postnatal challenges (postnatal reveal). We reared common murre (Uria aalge) chicks and measured prenatal exposure to corticosterone (CORT) and testosterone (T) from allantoic waste. Adrenocortical function was assessed after 10 …

Multi-Stress Proteomics: The Global Protein Response To Multiple Environmental Stressors In The Porcelain Crab Petrolisthes Cinctipes, Michael A. Garland

Master's Theses

Global climate change is increasing the number of hot days along the California coast as well as increasing the incidence of off-shore upwelling events that lower the pH of intertidal seawater; thus, intertidal organisms are experiencing an increase in more than one stress simultaneously. This study seeks to characterize the global protein response of the eurythermal porcelain crab Petrolisthes cinctipes to changes in thermal, pH, and tidal regime treatments, either combined or individually. The first experiment examined temperature stress alone and sought to determine the effect of chronic temperature acclimation on the acute heat shock response. We compared the proteomic …

Bioregulatory Systems Medicine: An Innovative Approach To Integrating The Science Of Molecular Networks, Inflammation, And Systems Biology With The Patient's Autoregulatory Capacity?, Alyssa W Goldman, Yvonne Burmeister, Konstantin Cesnulevicius, Martha Herbert, Mary Kane, David Lescheid, Timothy Mccaffrey, Myron Schultz, Bernd Seilheimer, Alta Smit, Georges St Laurent, Brian Berman

Medicine Faculty Publications

Bioregulatory systems medicine (BrSM) is a paradigm that aims to advance current medical practices. The basic scientific and clinical tenets of this approach embrace an interconnected picture of human health, supported largely by recent advances in systems biology and genomics, and focus on the implications of multi-scale interconnectivity for improving therapeutic approaches to disease. This article introduces the formal incorporation of these scientific and clinical elements into a cohesive theoretical model of the BrSM approach. The authors review this integrated body of knowledge and discuss how the emergent conceptual model offers the medical field a new avenue for extending the …

Gating Mechanisms Of The Canonical Trp Channel Isoform Trpc4, Dhananjay P. Thakur

Dissertations and Theses (Open Access)

Non-selective cation channels formed by Transient Receptor Potential Canonical (TRPC) proteins play important roles in regulatory and pathophysiological processes. These channels are known to be activated downstream from phospholipase C (PLC) signaling. However, the mechanism by which the PLC pathway activates TRPC4/C5 remains unclear. Uniquely, TRPC4 is maximally activated only when two separate G protein pathways, G_q/11 and G_i/o, are co-stimulated, making it a coincidence detector of G_q/11- and G_i/o -coupled receptor activation. Using HEK293 cells co-expressing mouse TRPC4β and selected G protein-coupled receptors, I observed that coincident stimulation of G_i/o proteins and …

The Effects Of Arginine Vasopressin On Maternal Behavior And Aggression In Peromyscus Californicus Mothers, Nathaniel Ng

Honors Projects

Research studies since the 1950s have shown that a chemical within the brain called arginine vasopressin (AVP) is associated with the modulation of many different social behaviors in mammals. Some of these behaviors are related to parenting, such as parental care initiation, aggression, social recognition, depression and anxiety. Understanding the physiology behind AVP regulation could allow for the creation of new therapies for treating human social disorders, such as using an AVP receptor antagonist to attenuate anxiety. This project examines how neural injections of AVP and an AVP receptor antagonist affect both maternal care and aggression in female Peromyscus californicus …

Expressing And Characterizing Mechanosensitive Channels In Xenopus Oocytes, Grigory Maksaev, Elizabeth S. Haswell

Biology Faculty Research

The oocytes of the African clawed frog (Xenopus laevis) comprise one of the most widely used membrane protein expression systems. While frequently used for studies of transporters and ion channels, the application of this system to the study of mechanosensitive ion channels has been overlooked, perhaps due to a relative abundance of native expression systems. Recent advances, however, have illustrated the advantages of the oocyte system for studying plant and bacterial mechanosensitive channels. Here we describe in detail the methods used for heterologous expression and characterization of bacterial and plant mechanosensitive channels in Xenopus oocytes.

The Reproductive Ecology Of The Timber Rattlesnake, Crotalus Horridus, In Northwestern Arkansas: Interactions Between Environment, Steroid Hormones, And Life History, Craig Michael Lind

Graduate Theses and Dissertations

In this dissertation I examined the relationship between individual energetic status, hormone production, and life history trait expression in field-active Timber Rattlesnakes, Crotalus horridus. In chapter one I reviewed what is known regarding these relationships in snakes and defined major research goals. In chapter two I described the seasonal profile of testosterone (T) and corticosterone (CORT) in relation to the breeding season and to individual energetic status in males. Results showed that the seasonal pattern of T production in C. horridus was different than other pit viper species with similar mating patterns. Testosterone was elevated in the months leading up …

Pathological Effects Of Repeated Concussive Tbi In Mouse Models: Periventricular Damage And Ventriculomegaly, Richard H. Wolferz Jr.

Honors Scholar Theses

Repeated concussive traumatic brain injury (rcTBI) is the most prominent form of head injury affecting the brain, with an estimated 1.7 million Americans affected each year (Kuhn 2012). Neurologists have been concerned about the danger of repeated head impacts since the 1920’s, but researchers have only begun to understand the long-term effects of rcTBI (McKee 2009). Although symptoms can be as mild as dizziness, current research suggests that multiple concussions can lead to a progressive degenerative brain disease known as chronic traumatic encephalopathy (CTE) (Luo 2008, McKee 2009, Kane 2013). Research on the brain is just beginning to scratch the …

Manipulation Of The Microbiome And Its Impact On Functional Recovery Following Ischemic Stroke, Michal Jandzinski

Honors Scholar Theses

Each year, nearly 800,000 individuals residing in the United States will have a stroke. Of these, about 130,000 cases will prove fatal while many of the survivors will be forced to live with disability for the remainder of their lives. Out of all strokes over 87% are ischemic strokes. The widespread incidence of this debilitating condition costs the United States an estimated $36.5 billion dollars every single year. Despite this, clinicians are armed with very little to combat the disease. Recent research developments have brought about the rise in awareness about the importance of the microbiome, the various gut flora …

Compensatory Review Addressing Acute Ischemic Strokes And Bell's Palsy, Patrick R. Godfrey

Celebrating Scholarship & Creativity Day (2011-2017)

In this study, I review the clinical diagnostic procedure for facial weakness; evaluate the physiological perspective of acute ischemic strokes and Bell's palsy; and assess possible consequences of Tissue Plasminogen Activator (tPA) treatment, and the ramification tPA has on Bell's palsy.

Successful Inquiry Based Activities In High School Physiology, Sowmya Anjur

Faculty Publications & Research

Physiology and Disease students at the Illinois Mathematics and Science Academy in Aurora employ inquiry driven activities to improve their understanding and articulation of the discipline. Students make heart models and make correlations with heart rate, lung capacity and blood pressure measurements. Students seemed to gain a better understanding of the cardiovascular unit as reflected in their heart unit assessment scores.

Tradeoffs Of Warm Adaptation In Aquatic Ectotherms: Live Fast, Die Young?, Eloy Martinez, Anthony Porreca, Robert Colombo, Michael Menze

Faculty Research & Creative Activity

In the face of a changing climate, questions regarding sub-lethal effects of elevated habitat temperature on the physiology of ectotherms remain unanswered. In particular, long-term responses of ectotherms to the warming trend in tropical regions are unknown, and understudied due to the difficulties in specimen and community traceability. In freshwater lakes employed as cooling reservoirs for power plants, increased physiological stress from high water temperature can potentially alter the community structure of fishes. We employ this highly tractable system to assess how thermal regimes can alter the physiology and ecology of aquatic species. We documented a significantly reduced lifespan, growth …

Development Of A Yeast-Based Assay For The Functional Characterization Of Fkbp52/ Î?-Catenin Interactions With The Androgen Receptor, Theresa Anne Rodriguez

Open Access Theses & Dissertations

Prostate cancer development is uniquely dependent on the androgen receptorâ??s (ARâ??s) transcriptional regulation in response to hormone binding. Current therapies directly target AR acting as an antagonist at androgen binding sites. However, once androgen-dependence is lost, meaning the patient has progressed into a late-stage hormone resistant phenotype, all current treatments are essentially ineffective. Utilizing the yeast strain Saccharomyces cerevisiae we are capable of creating a model system that allows for the exogenous expression of AR while still retaining the chaperone components needed for this steroid receptor complex. The 52kDa FK506 binding protein (FKBP52) has been shown to be an important …

Development Of Neuroendocrine Components Of The Thyroid Axis In The Direct-Developing Frog Eleutherodactylus Coqui: Formation Of The Median Eminence And Onset Of Pituitary Tsh Production., David H. Jennings, Bryce Evans, James Hanken

SIUE Faculty Research, Scholarship, and Creative Activity

Direct-developing frogs lack, wholly or in part, a wide range of larval features found in metamorphosing species and form adult-specific features precociously, during embryogenesis. Most information on thyroid regulation of direct development relies on hormone manipulations; the ontogeny of many thyroid axis components has not been fully described. This analysis examines differentiation of the median eminence of the hypothalamus and production of thyroid-stimulating hormone (TSH) by the pituitary of the direct-developing frog Eleutherodactylus coqui. The median eminence is established two-thirds of the way through embryogenesis. Cells immunoreactive to human TSHb antibodies are first detected during embryogenesis and quantitative changes in …

Restraint Stress Alters Pro-Inflammatory Cytokine Expression And Increases Superoxide Dismutase In The Rat Hypothalamus And Hippocampus, Kristina Isabel Barron

Open Access Theses & Dissertations

The impact of restraint stress on changes in cytokine expression and oxidative stress markers in hippocampal (Hipp) and hypothalamic (Hyp) regions of the brain, were assessed in a rat model. In addition, immune and inflammatory variables were assessed in peripheral blood. Male Wistar rats were acutely (30 min) or repeatedly (30 min/d for 14 consecutive days) exposed to a restraint stress, or maintained as non-stressed controls. At the time of sacrifice, whole blood and brain tissues enriched in Hyp or Hipp regions were collected; blood was collected with EDTA as an anticoagulant and centrifuged to yield plasma. All tissue samples …

Human Anatomy And Physiology Preparatory Course (1st Edition), Carlos Liachovitzky

Open Educational Resources

The overall purpose of this preparatory course textbook is to help students familiarize with some terms and some basic concepts they will find later in the Human Anatomy and Physiology I course.

The organization and functioning of the human organism generally is discussed in terms of different levels of increasing complexity, from the smallest building blocks to the entire body. This Anatomy and Physiology preparatory course covers the foundations on the chemical level, and a basic introduction to cellular level, organ level, and organ system levels. There is also an introduction to homeostasis at the beginning.

Mutations In The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Enlarge The Parasite's Food Vacuole And Alter Drug Sensitivities, Serena Pulcini, Henry M. Staines, Andrew H. Lee, Sarah H. Shafik, Guillaume Bouyer, Catherine M. Moore, Daniel A. Daley, Matthew J. Hoke, Lindsey M. Altenhofen, Heather J. Painter, Jainbing Mu, David J.P. Ferguson, Manuel Llinás, Rowena E. Martin, David A. Fidock, Roland A. Cooper, Sanjeev Krishna

Biological Sciences Faculty Publications

Mutations in the Plasmodium falciparum chloroquine resistance transporter, PfCRT, are the major determinant of chloroquine resistance in this lethal human malaria parasite. Here, we describe P. falciparum lines subjected to selection by amantadine or blasticidin that carry PfCRT mutations (C101F or L272F), causing the development of enlarged food vacuoles. These parasites also have increased sensitivity to chloroquine and some other quinoline antimalarials, but exhibit no or minimal change in sensitivity to artemisinins, when compared with parental strains. A transgenic parasite line expressing the L272F variant of PfCRT confirmed this increased chloroquine sensitivity and enlarged food vacuole phenotype. Furthermore, the introduction …

Understanding The Physiological Effects Of Suspended Material On Rainbow Trout (Oncorhynchus Mykiss), Tyler J. Weinhardt

Theses and Dissertations (Comprehensive)

The effect of global warming on northern environments is becoming increasingly evident. Melting of underlying permafrost is associated with widespread impacts in these environments. The loss of permafrost results in a destabilizing of underlying sedimentary layers resulting in thermokarst slumping. When this occurs on a large scale (mega-slumping) soil material becomes mobilized and is carried into local streams and rivers. The purpose of this study is to examine the sub-lethal physiological effects that suspended material has on rainbow trout (Oncorhynchus mykiss) in the context of the Peel River Plateau. Juvenile rainbow trout were exposed (following Environment Canada exposure …

The Effects Of Lampricide 3-Trifluoromethyl-4-Nitrophenol Toxicity On The Gills Of Larval Sea Lamprey And Non-Target Rainbow Trout And Lake Sturgeon, Lisa A. Sorensen

Theses and Dissertations (Comprehensive)

The pesticide, 3-trifluoromethyl-4-nitrophenol (TFM), is widely used in the Great Lakes to control invasive sea lampreys (Petromyzon marinus) populations, but much about its sub-lethal effects remains unknown. A better understanding of its toxicity is needed to improve TFM effectiveness and to protect non-target organisms from its potential adverse effects. The objectives of this thesis were to test the following two hypotheses: (1) impairment of mitochondrial ATP production by TFM interferes with ATP-dependent ion-uptake by fish, leading to altered electrolyte balance, and (2) perturbations of gill function by TFM are exacerbated in soft, ion poor water (SW; 40 mg …

The Reproductive Biology Of The Finetooth Shark, Carcharhinus Isodon, In The Northwest Atlantic Ocean, Amanda N. Brown

UNF Graduate Theses and Dissertations

Shark fisheries are a multimillion dollar industry in the United States and have significant contributions both recreationally and commercially. In order to maintain this industry, fisheries must be properly managed. An understanding of life history and reproduction is crucial in order to adequately manage shark fisheries. The finetooth shark, Carcharhinus isodon, is a member of the small coastal shark (SCS) fishery complex. It is found in Atlantic waters from South Carolina to Florida and throughout the Gulf of Mexico. This species has recently come under increased fishing pressure and has previously been overfished. New data is needed in order …

Molecular Identification And Functional Characteristics Of Peptide Transporter 1 (Pept1) In The Bonnethead Shark (Sphyrna Tiburo), Hannah Hart

UNF Graduate Theses and Dissertations

Many elasmobranchs are considered top predators with worldwide distribution, and in general these fish play an important role in the transfer of energy from the lower to the upper trophic levels within the marine ecosystem. Despite this, little research has been done regarding the rates of prey ingestion, digestion, and the processes of energy and nutrient absorption. Specifically understudied is enzymatic digestion within the intestinal brush border, which functions to break down macromolecules into smaller subunits for luminal absorption across the gastrointestinal epithelium. Given their carnivorous diet, the present study sought to expand knowledge on nutrient intake in elasmobranchs by …

The Effects Of Hibernation On The Hemostatic Properties Of The American Bullfrog, Rana Catesbeiana, Kiana Cullinan

Honors Program Theses

It is known that hibernating animals display a drastic reduction in metabolic rate, accompanied by reduced heart rate and rate of blood flow through vessels. Sluggish blood flow increases the risk for developing clots, yet it has been observed that hibernators conclusively display elongated clotting times. This observed impairment may be caused by the decrease in body temperature, due to a negative impact on the functioning of the enzymes involved in coagulation. Some hibernating endotherms, or “warm-blooded” animals, employ biological mechanisms as preventative means to prevent clotting during hibernation, such as the down-regulation of certain clotting factors or the production …

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 …

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 …

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 …

Metagenomic Identification Of A Novel Salt Tolerance Gene From The Human Gut Microbiome Which Encodes A Membrane Protein With Homology To A Brp/Blh-Family Beta-Carotene 15,15'-Monooxygenase, Eamonn P. Culligan, Roy D. Sleator, Julian R. Marchesi, Colin Hill

Department of Biological Sciences Publications

The human gut microbiome consists of at least 3 million non-redundant genes, 150 times that of the core human genome. Herein, we report the identification and characterisation of a novel stress tolerance gene from the human gut metagenome. The locus, assigned brpA, encodes a membrane protein with homology to a brp/blh-family β-carotene monooxygenase. Cloning and heterologous expression of brpA in Escherichia coli confers a significant salt tolerance phenotype. Furthermore, when cultured in the presence of exogenous β-carotene, cell pellets adopt a red/orange pigmentation indicating the incorporation of carotenoids in the cell membrane.

Clinical Investigation Of Plethysmographic Variability Index: A Derivative Index Of Pulse Oximetry In Anesthetized Dogs, Vaidehi V. Paranjape

Open Access Theses

Plethysmographic Variability Index (PVI) is a derivative index of pulse oximetry that allows evaluating an individual's intravascular volume status. Perfusion Index (PI) represents the strength of pulse signal at the anatomic site of measurement from which PVI is calculated using changes in PI over respiratory cycles. Plethysmographic Variability Index has been used to detect hypovolemia and predict fluid responsiveness in mechanically ventilated human patients however, fewer studies are available in spontaneously breathing patients. The use of PVI has not been explored extensively in dogs so far. The goals of this study were to establish a common range for PVI and …