Endocrinology Commons^™

Apobec3 Regulation By Thyroid Hormone, Michelle Santiago

All Graduate Theses, Dissertations, and Other Capstone Projects

Thyroid hormone (TH) is crucial for many biological processes, including the development of the auditory system. Appropriate thyroid hormone signaling is important for the development of the cochlea, leading to the successful onset of hearing. More specifically, TH influences the timing of remodeling of the greater epithelial ridge (GER), a transient cochlear structure that secretes proteins that contribute to the formation of the tectorial membrane. Developmental hypothyroidism results in delayed GER regression, whereas excess TH results in premature remodeling. Both conditions result in deafness. However, it is unknown how TH mediates GER remodeling. Expression profiling identified APOBEC3 (A3) as a …

Effects Of Social Context On Salivary Cortisol And Attention In Tufted Capuchins (Cebus [Sapajus] Apella), Andrew Desana

Master’s Theses

Social context alters cognitive performance, but the mechanisms for this remain unclear. One possibility is that stressors associated with social contexts mediate changes in cognitive performance by influencing attention. We conducted two experiments to investigate how social context affects performance on an attention task in capuchin monkeys (Cebus [Sapajus] apella). We additionally validated and measured physiological stress through salivary cortisol. In experiment one, capuchins were exposed to three conditions where they were either isolated or paired with an affiliative or agonistic social partner separated by a barrier. In experiment two, subjects received affiliative and agonistic conditions without barriers to allow …

Relationships Between Behavior, Energy Metabolites, And Corticosterone In Black-Legged Kittiwake (Rissa Tridactyla) Nestlings, Sierra Pete

Master’s Theses

Birds can cope with energy-shifting challenges by redirecting energy and behavior to maintain energetic homeostasis. Nestlings allocate energy to support their rapid growth and developmental period; thus, their challenges and the subsequent energetic demands can be much different than an adult. At a baseline level, energy is constantly shifting in response to regularly occurring challenges; however, more substantial challenges can initiate the production of glucocorticoid hormones. In birds, the main glucocorticoid is corticosterone. Corticosterone is believed to aid in energy homeostasis by redirecting energy metabolite mobilization. Energy metabolites are intermediaries or end products of cellular metabolism, thus, metabolites like glucose …

The Use Of A Habitat Quality Stress Index To Evaluate Stress As An Analog For Proximate Fitness In The American Crow Within A Matrix Of Landcover Characteristics To Assess Its Potential Contribution To Disease Etiologies, Theodore Lee Grabarz

Antioch University Dissertations & Theses

All organisms occur within spatial and temporal environments to maximize proximate fitness (health) and thus life history outcomes. Previous work has examined the temporal and behavioral aspects of proximate fitness on life history outcomes particularly regarding highly perturbed environments (i.e., climate and land use change, resource extraction, agricultural erosion, etc.). My work focuses on the less examined spatial aspect of these perturbed environments. More specifically, this dissertation examines habitat selection and quality as the basis for understanding stress response (negative and positive feedback mechanisms) to environmental stressors within the larger context of regional or gamma (ɣ) biodiversity. Through the lens …

Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman

Electronic Theses and Dissertations

The southern Appalachian Mountains have among the highest salamander diversity in the world, largely due to local speciation in the family Plethodontidae. Plethodontid salamanders (i.e., lungless salamanders) are particularly sensitive to habitat climate conditions due to their reliance on cutaneous respiration, and their immediate environmental conditions (microhabitat) likely influence their dispersion and activity more than the large-scale atmospheric conditions. The Northern Gray-cheeked salamander (Plethodon montanus) is restricted to high elevations in the Appalachian Mountains. Our goal was to investigate the relationship between P. montanus and its microhabitat by examining behavioral preference for climatic conditions, characterizing the microclimate with …

Investigating Host Defenses Of North American Salamanders Against The Recently Emerged Chytrid Pathogen, Batrachochytrium Salamandrivorans, Kenzie Pereira

Electronic Theses and Dissertations

A recently emerged chytrid fungal pathogen, Batrachochytrium salamandrivorans (Bsal) threatens salamander biodiversity. Bsal susceptibility varies between and within salamander species, but little is known about the mechanisms underlying these differences. Susceptibility is likely influenced by numerous interacting factors, but my dissertation studied the role of host immune responses.

My first aim investigated between species differences by studying the bioactive properties of salamander skin peptides against Bsal and the related pathogen, B. dendrobatidis (Bd). Skin peptides were collected from five salamander species, used for in vitro assays, and analyzed by RP-HPLC. While skin peptides from one …

Body Temperature And Diet As Drivers Of Obesity Development, Jessie Morrill

Dissertations and Theses (Open Access)

Metabolic disease and obesity affect millions of individuals worldwide and the prevalence of obesity is expected to continue to rise. Mechanisms underlying diet-induced metabolic disease and obesity are complex and are largely unknown. In this dissertation research, we aimed to make advances toward understanding how body temperature and high-fat diet consumption contribute to the development of obesity. Herein, we describe the progress that was made toward three research projects. In the first project, we develop novel animal models to determine the impact of reduced body temperature on obesity development and also demonstrate that severe obesity can be reversed through increased …

Diabetes-Related Outcomes Following Use Of Basal-Bolus Insulin Vs Premixed Insulin In A Va Population With Type 2 Diabetes: A Retrospective Chart Review., Ravisha Bai, Kavita Batra, Charmaine Yap, Kenneth Izuora

School of Medicine Faculty Presentations

No abstract provided.

A Multi-Species Study On Several Types Of Visitor Effects On The Behavior And Physiology Of Animals At The Oregon Zoo, Laurel Berylline Fink

Dissertations and Theses

The visitor effect on zoo animals is one of the expanding research topics in zoo animal research. As visitors are a mandatory feature of zoological institutions, understanding their effects on zoo animals is imperative for maximizing zoo animal welfare. Zoo animals are subject to many anthropogenic influences: visual, olfactory, and audible, for example. This dissertation investigates several of the effects of visitor presence and its relative influence on six mammalian species: cheetahs (Acinonyx jubatus), African painted dogs (Lycaon pictus), Asian elephants (Elephas maximus indicus & Elephas maximus borneensis), giraffes (Giraffa camelopardalis reticulata & …

Effects Of Sunrise/Sunset Lighting On Corticosterone Levels In Coturnix Quail (Coturnix Coturnix), Hannah Feuerborn

Poultry Science Undergraduate Honors Theses

Both genetics and environment play an important role in the growth, performance and overall welfare of poultry species. Current commercial production practices typically do not mimic the natural environmental conditions of ancestral poultry species, specifically lighting requirements. In nature, poultry species are subjected to natural day length and the slow rising and setting of the sun. This is compared to commercial conditions in which lights are sudden on/off, not mimicking the natural trajectory of the sun in terms of light intensity and exposure. The current study aimed to evaluate the impact of genetics and the effect of sunrise/sunset lighting on …

Effects Of Glucocorticoids Upon Pro-Inflammatory Responses To Acute Sleep Fragmentation, Hunter Weaver

Masters Theses & Specialist Projects

Sleep loss is a common problem in humans who suffer from obstructive sleep apnea. Sleep aids in the regulation of immune responses, some of which induce inflammatory responses. Cytokines regulate the inflammatory process and are released in response to sleep fragmentation (SF) in mice. Glucocorticoids are hormones that are released from the adrenal cortices during a stress response and are considered to be anti-inflammatory and immunosuppressive at high doses but may stimulate immune function on an acute level. The first hypothesis tested was that normal physiological expression of glucocorticoids (Sham) will display increased IL-1β and TNFα expression levels, while high …

Inflammatory Bowel Disease Causing Retroperitoneal Varicosity Mimicking A Renal Artery Aneurysm: A Novel Case Report And Literature Review, Areez Shafqat, Shameel Shafqat, Belal Nedal Sabbah, Abdullah Shaik, Wael Khalil Alfehaid, Syed Shafqat Ul Islam

Medical College Documents

A 17-year-old female presented to our hospital complaining of bloody diarrhea 4-6 times per day for the past month. She was a known case of inflammatory bowel disease noncompliant to her medications. Abdominal computed tomography revealed an unusually dilated mass in the retroperitoneum at L2 vertebral level connecting the lumbar and left renal veins. The renal artery was visualized separately, and a diagnosis of communicating vein varicosity was made. This lesion can be misleading on imaging, hence our aim to disseminate our findings to practicing radiologists. The differential diagnosis of these lesions include retroperitoneal lymphadenopathy, renal artery aneurysms, and testicular …

Effects Of Sunrise/Sunset Lighting On Corticosterone Levels In Coturnix Quail (Coturnix Coturnix), Hannah M. Feuerborn, Sara K. Orlowski

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Both genetics and environment play important roles in the growth, performance, and overall welfare of poultry species. Current commercial production practices typically do not mimic the natural environmental conditions of ancestral poultry species, specifically lighting. The current study aimed to evaluate the impact of genetics and the effect of sunrise/sunset lighting on the stress response of 4 genetic lines of Coturnix quail. The 4 lines utilized in this study included high stress (H), low stress (L), stress control (R), and Arkansas randombred (A) quail lines. Day old chicks from these lines were placed in one of two environmentally controlled rooms. …

The Use Of Exogenous Acrp30 As A Promising Amelioratory Compound Regarding Insulin Resistance And Type Ii Diabetes Mellitus, Stephen L. Romero

Honors Undergraduate Theses

As numerous bodies of research have characterized the adipocytokine adiponectin (ACRP30) as an anti-diabetic compound, this work serves as an analysis to partly elucidate the potential usage of supplementary adiponectin as a therapeutic compound in the treatment of type II diabetes mellitus. In this work, a meta-analysis was conducted to centralize large amounts of data on adiponectin’s insulin sensitizing characteristics in conjunction with like-minded studies utilizing metformin treatment as the diabetic standard of care. Upon comparison of fasting glucose, fasting insulin, and glucose tolerance test area under the curve reduction percentages, it is quite clear that ACRP30 has significant insulin …

Estrogen Regulation Of Daily Metabolic Rhythms In Female Mice, Oluwabukola Omotola

Theses and Dissertations--Biology

Circadian rhythms are approximately 24-hour cycles of behavior, physiology, and gene expression. In mammals, these circadian rhythms are generated by clocks located in nearly every tissue in the body. The function of circadian clocks is to synchronize physiology and behavior with environmental cycles such as the light-dark cycle. After menopause, when circulating levels of estrogens are very low, women are more susceptible to obesity comorbidities such as metabolic syndrome and cardiovascular disease, suggesting that estrogens regulate these processes. Estrogens could protect females from metabolic dysfunction by regulating circadian rhythms. Consumption of diets that are high in fat contribute to obesity. …

The Exposome, Metabolic Dysfunction And Silicosis: A Pulmonary And Pathophysiology Study, Janet A. Thompson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The exposome encompasses the concept that an individual’s health is a combination of genetic, environmental, and occupational exposures. A worker’s exposomal profile could potentially influence their susceptibility to hazardous occupational exposures. Over 35% of adults in the United States have metabolic dysfunction (MetDys), yet interactions between MetDys and hazardous occupational exposures are generally unknown. MetDys is associated with HFWD-consumption and obesity and induces a chronic low grade systemic inflammation and alters serum adipokine profiles. Silicosis, a progressive inflammatory lung disease, results from occupational inhalation exposure to respirable crystalline silica particles. This research tests the hypothesis “Inflammation resulting from HFWD-induced …

Effects Of Melatonin Implantation On The Activity Levels Of Captive Snow Buntings (Plectrophenax Nivalis), Zoë Ward

Mahurin Honors College Capstone Experience/Thesis Projects

In vertebrates, melatonin regulates many components of the circadian rhythm; depending on the organism’s location and time of year, the pineal gland will produce melatonin accordingly, controlling the sleep-wake cycle and breeding physiologies. However, locations at the poles in which the sun is above the horizon for multiple days at a time pose unique challenges for the organisms living there. The goal of this study was to examine how the implantation of melatonin in an arctic-breeding songbird affects its activity levels and circadian rhythm. The subject of this study, the snow bunting (Plectrophenax nivalis), is a small songbird …

Fertility Control Options For Management Of Free-Roaming Horse Populations, Ursula S. Bechert, John W. Turner Jr., Dan L. Baker, Douglas C. Eckery, Jason E. Bruemmer, Candace C. Lyman, Tulio M. Prado, Sarah R. B. King, Mark A. Fraker

Human–Wildlife Interactions

The management of free-roaming horses (Equus ferus) and burros (E. asinus) in the United States has been referred to as a “wicked problem” because, although there are population control options, societal values will ultimately determine what is acceptable and what is not. In the United States, free-roaming equids are managed by different types of organizations and agencies, and the landscapes that these animals inhabit vary widely in terms of access, size, topography, climate, natural resources, flora, and fauna. This landscape diversity, coupled with contemporary socioeconomic and political environments, means that adaptive management practices are needed to …

Scaling Of Computed Tomography Body Composition To Height: Relevance Of Height-Normalized Indices In Patients With Colorectal Cancer, Justin C. Brown, Steven B. Heymsfield, Bette J. Caan

School of Medicine Faculty Publications

Background: Body weight scales to height with a power of ≈2 (weight/height2), forming the basis of body mass index (BMI). The corresponding scaling of body composition measured by abdominal computed tomography (CT) to height has not been established. The objective of this analysis was to quantify the scaling of body composition measured by a single-slice axial abdominal CT image (skeletal muscle, and visceral, subcutaneous, and total adipose tissue) to height in patients with colorectal cancer (CRC). Methods: This cross-sectional study included non-Hispanic white males and females, aged 18–80 years, who were diagnosed with stage I–III CRC at an integrated health …

Modulation Of Glucose Homeostasis By Nucleotide P2y2 Receptor And Biological Sex, Hailee Anne Marino

Graduate Theses/Dissertations

Recent insights into the pathological role of Nucleotide P2Y₂ receptor suggest P2Y₂R involvement in high fat diet-induced obesity and potentiates insulin resistance. However, these recent insights do not demonstrate how P2Y₂R modulates glucose homeostasis under physiological conditions. Further, it remains unknown how sex biological factors influence P2Y₂R receptor signaling in the regulation of glucose homeostasis. The research objective for the present study is to elucidate the novel roles of P2Y₂ in fasting blood glucose and glucose tolerance (basal insulin sensitivity) under resting conditions in males and females. We expected that under physiological …