Physiology Commons^™

Novel Regulators Of Small G Proteins In The Pancreatic Beta Cell, Noah Gleason

Wayne State University Dissertations

Regulation of small GTPases within the pancreatic beta cell is a highly complex and coordinated sequence of protein interactions and post translational modifications. Various families participate in the physiological secretion of insulin in roles ranging from cytoskeletal reorganization to secretory vesicle priming and docking. However the regulatory partners of GTPase function, while studied broadly, lack vital information relating to smgGDS, a protein chaperone of small GTPases to and from the prenylation machinery, and RhoGDI function. Herein these studies are aimed to further our understanding of GTPase regulation and alterations that occur during metabolic stress (glucotoxicity) and related beta cell dysfunction.Data …

Novel Methods For Assessing Pulmonary And Cardio-Vascular Limitations To Aerobic Performance In Older And Younger Populations, Toni Haddad

Theses: Doctorates and Masters

Around the world, life expectancy is increasing, the ageing population is growing, and maintaining quality of life at an older age currently represents a major global challenge. While ‘successful ageing’ relies on a variety of factors, aerobic performance and exercise capacity are key determinants and attenuating their decline is of the utmost importance. The decrease in maximal oxygen consumption is often considered as a major determinant explaining the age[1]related decline in aerobic performance. Yet, multiple physiological systems are impaired with ageing and their contribution to aerobic limitation in older individuals is unclear. Understanding how the limitations to aerobic performance may …

Comparing Ionoregulation And Modes Of Nitrogen Excretion Across The Life Cycle Of Parasitic And Non-Parasitic Lamprey Species, Shannon Davidson

Theses and Dissertations (Comprehensive)

Abstract

Ionoregulation and nitrogenous waste (N-waste) metabolism in fishes has been extensively documented in teleosts and elasmobranchs, but less so in lampreys (Petromizontiformes). All lamprey species undergo metamorphosis which drastically changes their physiology and modes of feeding. However, differences in ionoregulatory mechanisms due to anadromous versus non anadromous life history strategies emerge following metamorphosis in different lamprey species. Furthermore, some species, such as anadromous juvenile sea lamprey (Petromyzon marinus), are parasitic and migrate to seawater (SW) to ingest blood protein from host fishes, while juveniles of freshwater (FW), non-parasitic species, such as the American brook lamprey …

Chromatin Regulation By Swi/Snf Remodelers In Somatic Stem Cell Maintenance And Transformation, Luke Thomas Deary

Dartmouth College Ph.D Dissertations

Cell identity is defined by the epigenome, whereby chromatin regulators work in concert to promote gene expression programs that serve a cell’s specialized purpose. Mutations in chromatin regulators are amongst the most frequent drivers of human disease, underscoring the importance of understanding their activities in maintaining cell identity and tissue function. In particular, mutations in subunits of the evolutionarily conserved SWI/SNF chromatin remodeling complexes drive diseases across human tissues in both development and adult tissue maintenance5. Three major SWI/SNF complexes exist: BAF, PBAF, and GBAF, which differ in their composition and genomic targeting but share an ATP-dependent catalytic activity to …

Modulation Of Persistent Inward Currents With Changes In Posture And Cutaneous Sensory Input, Ryan William Weller

Theses and Dissertations (Comprehensive)

Spinal motor neuron (MN) persistent inward currents (PIC) increase and sustain the MN output. PIC is amplified by descending monoamines and reduced by afferent inhibition. There is strong coupling between plantar cutaneous sensory input and lower limb MNs. Given that monoaminergic drive is altered with postures and motor tasks, our purpose was to assess posture-dependent plantar cutaneous sensory modulation of tibialis anterior (TA) MNs. We hypothesize that: 1) a supine position will suppress PIC, 2) removing the load from the bottom of the heel will inflate PIC, and 3) cutaneous stimulation of the plantar aspect of the heel will reduce …

Turtlegrass (Thalassia Testudinum) Undergoes A Coordinated Hypersensitive Response When Challenged With Pathogenic Labyrinthula Sp., Ava Vasile Larson

UNF Graduate Theses and Dissertations

Infection of the subtropical seagrass Thalassia testudinum Banks ex König by pathogenic Labyrinthula sp. was found to induce lesion progression, alterations to the host’s oxidative metabolism, and production of defense metabolites over the early stages of infection (monitored over a 72-hr time course). By 48-hrs post-infection, host oxygen consumption, internal reactive oxygen concentrations, and caspase-3 proteolytic activity reached their highest levels. The formation of reactive oxygen species (ROS) and nitric oxide (NO) were detected in T. testudinum lesions by use of redox-sensitive probes/substrates and fluorescent imaging. To our knowledge, this work represents the first time NO has been detected in …

Puberty-Associated Changes In Kiss1r, Mc3r, And Mc4r In The Ewe, Ashleigh Caitlyn Thomson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The neural mechanisms that control the onset of puberty are not completely understood. In livestock, the onset of puberty relies on an increase in gonadotropin releasing hormone (GnRH) and luteinizing hormone (LH). Kisspeptin, neurokinin B, and dynorphin neurons (KNDy) and their receptors, Kiss1r, NK3R, and KOR, respectively, are important regulators of puberty. Previous data from our laboratory has shown that KNDy neurons may be responding to other inputs, including the melanocortin system, that will affect the timing of puberty. Given this, we examined kisspeptin receptor (Kiss1r) mRNA expression in GnRH neurons as well as examining melanocortin 3 and 4 receptor …

Immune Outcomes Affected By Selection For Parasite Resistance In Katahdin Sheep, Kelsey Lynne Bentley

Graduate Theses, Dissertations, and Problem Reports (ETD)

Our understanding of the complex connection between selection for parasite resistance and the overall health outcomes in livestock is unclear. This study investigates the impact of post-weaning fecal egg count (PFEC) estimated breeding values (EBV) on health outcomes and immune responses in Katahdin sheep. Selection for PFEC, favoring Low-PFEC lambs, not only affects survivability to weaning but also suggests broader implications for immunity beyond parasite resistance. The effect of PFEC EBV on antibody production in response to vaccination against Clostridium perfringens type C&D and tetanus toxoid (CD&T) revealed a stepwise decrease in immunoglobin (IgG) from Low-PFEC to High-PFEC groups upon …

Utilizing Ai Integrated Neuroimaging Technology To Expand Upon Machine Learning In Positron Emission Tomography Technology With The Aim Of Detecting Amyloid Beta Biomarkers Early In The Onset Of Alzheimer's., Ethan S. Terman

Undergraduate Research Posters

Early intervention in Alzheimer's is vital for treatment. The earlier a professional can detect symptoms and make a diagnosis the earlier a prognosis can be implemented. With the prevalence of data in our day-to-day world combined with Artificial intelligence (AI), utilizing both for machine learning can pave the way for more accurate and efficient detection of Alzheimer's and other neurodegenerative diseases. AI combined with Machine learning (ML) increases diagnostic efficiency and reduces human errors, making it a valuable resource for physicians and clinicians alike. With the increasing amount of data processing and image interpretation required, the ability to use AI …

Carry-Over Effects Of Climate On Prothonotary Warbler (Protonotaria Citrea) Feather Quality, Alyssa N. Spasic, Dan Albrecht-Mallinger, Lesley Bulluck

Undergraduate Research Posters

Avian species have inspired numerous studies on ornamentation, exploring its role in intra- and intersexual selection as a marker for individual quality. Male birds have been the focus of most of these studies while females, which can also display ornamentation, have been studied less. Coloration achieved through molt, particularly carotenoid-based pigments, requires energy derived from food resources. As climate affects insect abundance, there may be a link between climate conditions during molt and feather quality the following season. We assessed the relationship between temperature and precipitation during molt and female Prothonotary Warbler (Protonotaria citrea) breast and crown feather reflectance metrics …