Physiology Commons^™

Monitoring Relationships Between Corticosterone And Snake Fungal Disease In Timber Rattlesnakes (Crotalus Horridus) In Western Kentucky, John Bromley Hewlett

Murray State Theses and Dissertations

Over the past four decades, emergent fungal diseases have been the most devastating relative to species declines and extinctions. While most research has focused on fungal diseases affecting amphibians and bats, less has focused on diseases like snake fungal disease (SFD), caused by Ophidiomyces ophiodiicola (Oo). SFD was first described in 2006 in North America within a Timber rattlesnake (Crotalus horridus) population in New Hampshire. Since then SFD has been documented in 19 US states, one US territory (Puerto Rico), and Europe. SFD causes high mortality in some species, including the Eastern Massasauga rattlesnakes (Sistrurus …

Males Of The Wolf Spider Rabidosa Rabida Use Two Mechanisms To Stun Females During Copulation, Daniel Schoenberg

Murray State Theses and Dissertations

The differences in energetic input between the sexes required to produce gametes translates to the differences in reproductive behavior and overall mating systems seen in a species. Females generally produce a few energetically and resource expensive eggs and typically choose a high-quality suitor to ensure she has high quality offspring. In contrast, males produce abundant energetically cheap sperm and attempt to fertilize as many eggs as possible in as many females as possible. Both sexes are trying to maximize their inclusive fitness, but the dichotomy of interests can lead to sexual conflict and perhaps extreme or unusual behaviors such as …

Estrogen Disruption Of Hypothalamic Neural Activity, Princess Dickson

Cal Poly Humboldt theses and projects

The brain is highly dependent on the endocrine system for proper neurodevelopment, as it plays a key role in many biological processes. Bisphenol A is a chemical found in plastics that has the potential to mimic the effects of Estrogen in the body, at least weakly. People interact with plastic that contains BPA regularly, and people are at risk for exposure even before being born. The abundance of BPA, along with other exogenous estrogens, makes examining the relationship between early exposure and changes in brain activity imperative. The current study aims to establish a relationship between disrupted estrogen function and …

Characterization Of Spontaneous Preeclampsia In The African Green Monkey (Chlorocebus Aethiops Sabaeus), Chelsea Christina Weaver

Theses and Dissertations--Biology

Hypertensive pregnancy disorders are a major contribution to maternal and neonatal mortality worldwide. Two of these disorders, preeclampsia and chronic hypertension in pregnancy, affect up to 10% of all pregnancies. These hypertensive disorders of pregnancy are associated with long-term, postnatal risk factors for both mother and offspring. Despite numerous recent advances in preeclampsia research, the underlying mechanisms are still not understood. This could be due to lack of a spontaneous animal model. This dissertation presents the African Green Monkey (AGM; Chlorocebus aethiops sabaeus) as the first known spontaneous animal model of preeclampsia and a highly translational model of chronic …

The Effects Of Food Supply On Reproductive Hormones And Timing Of Reproduction In An Income-Breeding Seabird, Shannon Whelan, Scott A. Hatch, Z. Morgan Benowitz-Fredericks, Charline Parenteau, Olivier Chastel, Kyle Elliott

Faculty Journal Articles

Current food supply is a major driver of timing of breeding in income-breeding animals, likely because increased net energy balance directly increases reproductive hormones and advances breeding. In capital breeders, increased net energy balance increases energy reserves, which eventually leads to improved reproductive readiness and earlier breeding. To test the hypothesis that phenology of income-breeding birds is independent of energy reserves, we conducted an experiment on food-supplemented (“fed”) and control female black-legged kittiwakes (Rissa tridactyla). We temporarily increased energy costs (via weight handicap) in a 2 × 2 design (fed/unfed; handicapped/unhandicapped) during the pre-laying period and observed movement …

Creating A Georgia Southern Spider Collection: Can Dna Barcoding Help?, Guy B. Hobbs

College of Graduate Studies: Theses & Dissertations

With over 280 spider (Araneae) species recorded within the State of Georgia, USA, the need for a well-documented natural history collection with a usable voucher system is critical to continually assess spider diversity and their future ecological impact in this region. Spider identification can be daunting for the inexperienced taxonomist; it is time consuming and sometimes requires destructive procedures. Previous works have successfully used an alternative method, DNA barcoding, to correctly identify spider species while preserving their morphology. This study set forth to create the core of a well-documented spider collection within Georgia Southern University’s Institute for Coastal Plain Science …

Novel Quantification And Localization Of Water And Solute Transporters In The Tissues Of The Spiney Dogfish (Squalus Acanthias), Tolulope B. Ojo

College of Graduate Studies: Theses & Dissertations

The dogfish, Squalus acanthias is a marine cartilaginous elasmobranch found in the North Atlantic and Pacific oceans. Dogfish synthesize and excrete urea as a product of nitrogen metabolism. They also convert ammonia into urea and retain this urea, such that their plasma is isosmotic or slightly hyperosmotic to the surrounding seawater. To facilitate the regulation of body fluid and to maintain ionic concentrations and osmotic pressure, Dogfish use ion and solute transporters (e.g., NCC, UT-1) and aquaporin water channel proteins. Studies have identified some of the aquaporin genes in the elasmobranch genome, but their functions are mostly uncharacterized. Recent transcriptomic …

Inhibition Of Oxidative Metabolism By Nitric Oxide Restricts Emcv Replication Selectively In Pancreatic Beta-Cells, Joshua D. Stafford, Chay Teng Yeo, John A. Corbett

Biological Sciences Faculty Research & Creative Works

Environmental factors, such as viral infection, are proposed to play a role in the initiation of autoimmune diabetes. In response to encephalomyocarditis virus (EMCV) infection, resident islet macrophages release the pro-inflammatory cytokine IL-1b, to levels that are sufficient to stimulate inducible nitric oxide synthase (iNOS) expression and production of micromolar levels of the free radical nitric oxide in neighboring b-cells. We have recently shown that nitric oxide inhibits EMCV replication and EMCV-mediated b-cell lysis and that this protection is associated with an inhibition of mitochondrial oxidative metabolism. Here we show that the protective actions of nitric oxide against EMCV infection …

Control Of Blood Volume Following Hypovolemic Challenge In Vertebrates: Transcapillary Versus Lymphatic Mechanisms., Stanley S. Hillman, Robert C. Drewes, Michael S. Hedrick

Biology Faculty Publications and Presentations

Anurans have an exceptional capacity for maintaining vascular volume compared with other groups of vertebrates. They can mobilize interstitial fluids via lymphatic return at rates that are ten-fold higher than mammals. This extraordinary capacity is the result of coordination of specialized skeletal muscles and pulmonary ventilation that vary volume and pressure of subcutaneous lymph sacs, thus moving lymph to dorsally located lymph hearts that return lymph to the vascular space. Variation in the capacity to mobilize lymph within anurans varies with the degree of terrestriality, development of skeletal muscles, lung volume and lung compliance, and lymph heart pressure development. This …

Influence Of Testosterone On Male-Male Competition In The Red-Sided Garter Snake, Thamnophis Sirtalis Parietalis, Isabella M. G. Bukovich

Senior Honors Projects, 2020-current

Female mimicry in the red-sided garter snake, Thamnophis sirtalis parietalis, is described in several well-studied evolutionary advantages, but an aspect that remains elusive is how reproductive traits are linked to the 3-fold higher circulating androgens in males with this phenotype. In this study, we implanted male garter snakes (n=15 per group) with either a blank implant (SHAM; control) or a T implant, the latter simulating the female mimic phenotype. Following simulated low-temperature dormancy, males were scored for courtship intensity over three days of behavioral trials with females housed in the same facility. Males were sacrificed, and sperm were collected …

A Brain-Infecting Parasite Impacts Host Metabolism Both During Exposure And After Infection Is Established, Lauren E. Nadler, Erik Bengston, Erika J. Eliason, Cameron Hassibi, Siri H. Helland-Riise, Ida B. Johansen, Garfield T. Kwan, Martin Tresguerres, Andrew V. Turner, Kelly L. Weinersmith, Øyvind Øverli, Ryan F. Hechinger

Marine & Environmental Sciences Faculty Datasets

1. Metabolic costs associated with parasites should not be limited to established infections. Even during initial exposure to questing and attacking parasites, hosts can enact behavioural and physiological responses that could also incur metabolic costs. However, few studies have measured these costs directly. Hence, little is known about metabolic costs arising from parasite exposure.
2. Further, no one has yet measured whether and how previous infection history modulates metabolic responses to parasite exposure.
3. Here, using the California killifish (Fundulus parvipinnis) and its brain-infecting parasite (Euhaplorchis californiensis), we quantified how killifish metabolism, behaviour, and osmoregulatory phenotype changed upon acute …

Inhibition Of Mitochondrial Oxidative Metabolism Attenuates Emcv Replication And Protects B-Cells From Virally Mediated Lysis, Joshua D. Stafford, Zachary R. Shaheen, Chay Teng Yeo, John A. Corbett

Biological Sciences Faculty Research & Creative Works

Viral infection is one environmental factor that may contribute to the initiation of pancreatic b-cell destruction during the development of autoimmune diabetes. Picornaviruses, such as encephalomyocarditis virus (EMCV), induce a pro-inflammatory response in islets leading to local production of cytokines, such as IL-1, by resident islet leukocytes. Furthermore, IL-1 is known to stimulate b-cell expression of iNOS and production of the free radical nitric oxide. The purpose of this study was to determine whether nitric oxide contributes to the b-cell response to viral infection. We show that nitric oxide protects b-cells against virally mediated lysis by limiting EMCV replication. This …

Wnt/_-Catenin Mediated Regulation Of Murine And Human Cardiac Electrophysiology And Arrhythmogenesis, Gang Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cardiac arrhythmias affects millions of Americans and can lead to sudden cardiac death, accounting for more than 300,000 deaths annually. Despite the vast knowledge available for cardiac disease and associated arrhythmias, very few effective therapies exist. Current interventions include cardioverter defibrillators and antiarrhythmic drugs targeting ion channels or the _-adrenergic pathway. In most acquired and inherited arrhythmias, molecular signaling pathways are perturbed. However, little is known about the underlying mechanism of how these signaling pathways regulate cardiac electrophysiology. Therefore, a better understanding of major signaling pathways governing cardiac development or dysregulated in cardiac disease could lead to novel therapeutics for …

Drosophila Model To Study Muscle Atrophy, Aaron Aghai

Master of Science in Integrative Biology Theses

Muscle atrophy (MA) is a phenomenon of muscle mass loss due to accelerated protein degradation in muscle fibers. Some pathological conditions, such as chronic inflammation or cancer, induce accelerated MA, which complicates medical treatment, hampers recovery of fragile patients, and ultimately can be the cause of a patient’s death. To gain better control over MA, more information is required about the whole spectrum of genetic factors that can influence MA.

Drosophila provides an excellent platform for genetic screening, although it has somewhat limited utility for MA research since insect muscles lack the level of plasticity found in mammalian muscles. We …

Impacts Of Tourism On The Ecophysiology Of The Endangered Northern Bahamian Rock Iguana (Cyclura Cychlura), Alison C. Webb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increased interest in ecotourism over recent years has led to more direct human-animal interactions and a striking concomitant increase in the provisioning of non-natural food, that may have unintended consequences for the wildlife involved. The critically endangered Northern Bahamian Rock Iguana provides a valuable model to address the potential impact of food provisioning on health as there are populations that represent a graded variation in human presence, with sites experiencing high, low, or no tourism. To assess the potential impacts of tourism on iguana physiology I first reviewed the relevant literature on iguana physiology and then performed three investigations focusing …

Assessing Well-Being Of Asian Elephants (Elephas Maximus) Through Major Events And Transitions, With Development And Aging, And Husbandry Changes, Sharon Stuart Glaeser

Dissertations and Theses

In this body of research, reproductive and adrenal hormones and behavior were used to evaluate individual and group responses to physiological, social, and environmental changes in zoo-housed Asian elephants, considering factors of sex, age, and life stage. Animals experience physiological, social, and environmental changes as part of their natural history and individual life experience. Measures of both positive and negative states are needed to assess the impact of these changes at the individual and group level. Such measures can help us better understand how animals cope with a changing environment, and can help inform management decisions. Through longitudinal analyses of …

Energy Stores And Life-History Transitions In Red-Sided Garter Snakes (Thamnophis Sirtalis Parietalis), Rachel Catharine Wilson

Dissertations and Theses

All organisms must prioritize investment in either reproductive or self-maintenance activities. Despite this established paradigm, our understanding of how organisms choose to prioritize certain behaviors and physiologies over others remains limited. It is likely that an organism's energy status not only influences variation in reproductive effort, but also transitions to and from reproductive activities. My dissertation aims to investigate how energy metrics (body condition index, adipocyte follicle size, and liver glycogen) relate to reproduction and associated life-history stages in red-sided garter snakes (Thamnophis sirtalis parietalis). Chapter two examines if energy metrics differ with migratory status and sex in …

Circadian Disruption With Constant Light Exposure Exacerbates Atherosclerosis In Male Apolipoproteine-Deficient Mice, Jeffrey M. Chalfant, Deborah A. Howatt, Lisa R. Tannock, Alan Daugherty, Julie S. Pendergast

Biology Faculty Publications

Disruption of the circadian system caused by disordered exposure to light is pervasive in modern society and increases the risk of cardiovascular disease. The mechanisms by which this happens are largely unknown. ApolipoproteinE-deficient (ApoE^−/−) mice are studied commonly to elucidate mechanisms of atherosclerosis. In this study, we determined the effects of light-induced circadian disruption on atherosclerosis in ApoE^−/− mice. We first characterized circadian rhythms of behavior, light responsiveness, and molecular timekeeping in tissues from ApoE^−/− mice that were indistinguishable from rhythms in ApoE^+/+ mice. These data showed that ApoE^−/− mice had no inherent circadian …

Determining The Genetic Control Of Neural Tube Malformation Through Genetic Interactions With Idgf3, Elli N. Fox

Honors Projects

Genetic mutations disrupting human neural tube formation can lead to birth defects such as spina bifida and anencephaly. Defects can result in lack of neural tube closure in either the caudal (spina bifida) or cranial (anencephaly) regions. Little is known about the genes that cause these malformations. Researchers have been using the model organism Drosophila melanogaster in an attempt to determine genes responsible for neural tube malformations. Recently, an ortholog of human chitin-like protein, imaginal disc growth factor 3 (Idgf3), has been identified as important in the proper formation of Drosophila egg dorsal appendages. However, the molecular mechanism responsible for …

The Effect Of Intensified Illuminance And Artificial Light At Night On Fitness And Susceptibility To Abiotic And Biotic Stressors, Grascen Shidemantle

Biological Sciences Student Scholarship

Changing light conditions due to human activities represents an important emerging environmental concern. Although changes to natural light conditions can be independently detrimental, in nature, organisms commonly face multiple stressors. To understand the consequences of altered light conditions, we exposed a model amphibian (wood frog; Lithobates sylvaticus) to a control and two anthropogenic light conditions: intensified daytime illuminance and artificial light at night - ALAN (intensified daytime illuminance + extended photoperiod). We measured (1) metrics of fitness (hatching success as well as survival to, size at, and time to metamorphosis) (2) susceptibility (time to death) to a commonly cooccurring anthropogenic …

Physiological And Behavioral Correlates Of Hif-1 Alpha Protein Levels In The Gulf Killifish, Fundulus Grandis, Jasmine Harris

LSU New Orleans Theses and Dissertations

Although the hypoxia-inducible transcription factor (HIF) orchestrates molecular responses to low oxygen, the amount of HIF-1α protein expressed during hypoxia varies among species, individuals, and tissues. This study measured HIF-1α protein levels along with several physiological and behavioral variables in the estuarine fish Fundulus grandis under normoxia (> 7 mg l^-1 dissolved oxygen) and hypoxia (1 mg l^-1 dissolved oxygen). Fish under hypoxic conditions had higher tissue levels of HIF-1α, hematocrit, blood glucose, blood lactate, frequency of aquatic surface respiration (ASR), and lower activity than normoxic controls. Under hypoxia, HIF-1α abundance in gill was positively correlated with body …

Comparative Study Of Spectral Sensitivity, Irradiance Sensitivity, Spatial Resolution And Temporal Resolution In The Visual Systems Of Aratus Pisonii And Ocypode Quadrata, Ruchao Qian

All HCAS Student Capstones, Theses, and Dissertations

Autrum’s studies (1950, 1958) on terrestrial arthropods first revealed that the visual systems of arthropods reflected their lifestyles and habitats, demonstrating that rapidly moving predatory diurnal species tend to have better temporal resolution than slower moving nocturnal species. In order to test Autrum’s hypothesis that visual adaptions are driven by predator/prey interactions, the visual physiology of a nocturnal fast-moving predatory crab, the Atlantic ghost crab (Ocypode quadrata), and a diurnal herbivorous crab, the mangrove tree crab (Aratus pisonii), was examined and compared. Spectral sensitivity, irradiance sensitivity, and temporal resolution of the crabs were quantified using the …

Characterizing The Role Of Β-Amylase3 In Cold Stress Response And Recovery In Arabidopsis Thaliana, Isabelle G. Houston

Senior Honors Projects, 2020-current

Starch is a polymer of glucose that is used as an energy store in plants. Mobilization of starch has implications in abiotic stress survival and recovery. While the importance of carbon and energy allocation in plant survival has been explored, the specific roles of starch degrading enzymes in plant responses to stress are still unclear. β-Amylase3, or BAM3, is the principle starch degrading enzyme at night and is transcriptionally upregulated in response to cold stress in the plant Arabidopsis thaliana. Using single and quadruple knockout mutant plants, I aimed to clarify the role of BAM3 in the response to …

Microglia-Neuron Interactions In A Mouse Model Of Low Grade Neuroepithelial Tumors, Veolette Hanna

Honors Scholar Theses

Microglia are the macrophages of the brain and spinal cord, playing an important role in the immune response to disease states of the nervous system. This study conducts an investigation on the activity of microglia in response to low grade neuroepithelial tumors. Using mouse models and microglial markers, a qualitative and quantitative analysis of microglia activation, migration, and invasion within the brain cortex during early stages of tumor development was conducted. It was found that the presence of a low grade neuroepithelial tumor in the cortex of one hemisphere of the brain causes significant microglia activation in comparison to the …

Rapid Evolution Of Starvation Resistance In Drosophila: Physiological And Molecular Mechanisms, Austin Joseph Mckenna

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Gibbs lab has maintained starvation-selected Drosophila melanogaster for >130 generations. These starvation-selected flies evolved an obese phenotype with a suite of physiological differences compared to control-fed flies. Previous studies have shown that long-term starvation-selected Drosophila contain more lipids, have lower metabolic rates and develop more slowly than controls. This dissertation encompasses 1) Examining the molecular mechanisms contributing to starvation resistance, 2) Functional validation of the candidate plin1 allele, and 3) Rapid physiological and genomic evolution in starvation-selected Drosophila.

Starvation-selected Drosophila survive starvation conditions much longer than control-fed flies. This study took a simple approach to identify possible differences in …

Effects Of Pharmacologically-Induced Sleep Loss On Parental Care In Arctic-Breeding Songbirds, Wesley Payette

Masters Theses & Specialist Projects

Sleep loss is well known to impair cognitive function, immunological responses, and general well-being in humans. However, sleep requirements in mammals and birds may vary dramatically, especially with changes in environment. In circumpolar regions with continuous light, sleep requirements may be little, particularly in breeding birds. The effects of sleep loss on several fitness parameters were examined in two species of Arctic-breeding passerine birds: Lapland longspurs (Calcarius lapponicus) and snow buntings (Plectrophenax nivalis). Adult males were implanted during the nestling phase (4 days post-hatch) with osmotic pumps containing an anti-narcolepsy drug, modafinil, to extend the active period for 72 h. …

Reconsidering Undergraduate Anatomy And Physiology Curriculum, Eric Michael Walsh

Theses and Dissertations

In the past 50 years several convergent factors have spurred unprecedented change in anatomy and physiology (A&P) instruction. An explosion of biomedical knowledge, an increased demand for students well-versed in A&P, and decreased resources for the course has provoked a vast array of research. However, most studies employ one of three strategies to enact change: testing the effectiveness of new pedagogies, exploring the utility of new technologies, or documenting learning in new contexts. By comparison, a much smaller body of research focuses on changing the A&P curriculum to improve student learning. To address this gap, the musculoskeletal curriculum for an …

Life Line March 2020, Otterbein Biology And Earth Science Department

Life Line - The Biology Department Newsletter

The Department Welcomes Dr. Sinn; Modeling to Help with Global Research; The Paradise of Bombs Revisited; The End of an Era in Conesville Ohio; Reports from two recipients of the Melinda Phinney Award for Pre-Med Travel Experiences; Preparing Skins for Study; Genomics in the Jungle; Zoo Program Gets New T -Shirt and Sweatshirt Designs; Aquarium Track Dives Right In; Dr. Svitana’s Sabbatical Accomplishments;Biology Behind Bars; Grossology: The Science of Icky, Sticky, Disgusting Things.

Targeting Cancer-Anorexia Cachexia Syndrome And Septic Inflammatory-Based Atrophy With R/S 1,3 Butanediol Acetoacetate Diester, Andrew P. Koutnik

USF Tampa Graduate Theses and Dissertations

Cancer anorexia cachexia syndrome (CACS) is a distinct atrophy disease negatively influencing multiple aspects of clinical care and patient quality of life. Although it directly causes 20% of all cancer-related deaths, there are currently no model systems that encompass the entire multifaceted syndrome, nor are there any effective therapeutic treatments. Here, we show that the VM-M3 mouse model of systemic metastasis demonstrates a novel, immunocompetent, logistically feasible, repeatable phenotype with progressive tumor growth, spontaneous metastatic spread, and the full multifaceted CACS with expected sex dimorphisms across tissue wasting. We also demonstrate that the ubiquitin proteasomal degradation pathway was significantly upregulated …

The Location Of Sensing Determines The Pancreatic Β-Cell Response To The Viral Mimetic Dsrna, Zachary R. Shaheen, Joshua D. Stafford, Michael G. Voss, Bryndon J. Oleson, Jennifer S. Stancill, John A. Corbett

Biological Sciences Faculty Research & Creative Works

Viral infection is an environmental trigger that has been suggested to initiate pancreatic β-cell damage, leading to the development of autoimmune diabetes. Viruses potently activate the immune system and can damage β-cells by either directly infecting them or stimulating the production of secondary effector molecules (such as proinflammatory cytokines) during bystander activation. However, how and where β-cells recognize viruses is unclear, and the antiviral responses that are initiated following virus recognition are incompletely understood. In this study, we show that the β-cell response to dsRNA, a viral replication intermediate known to activate antiviral responses, is determined by the cellular location …