Biology Commons^™

From Young To Old: The Effects Of Sedentary-Aging And Exercise Interventions On Structural Plasticity Of Lumbar Motor Neurons, Nmj, And Glial Cell Line-Derived Neurotrophic Factor Expression, Alberto Felipe Cintron-Colon

Dissertations

Neuromuscular weakness has been associated with age progression. A possible reason is a disconnection between muscle and neuron, causing components from both the central and peripheral nervous systems to deteriorate. Exercise, however, has beneficial effects for both muscle and nervous tissue, inducing neuroprotection. Neurotrophic factors are powerful regulators of neuronal maintenance and synaptic strength. Glial cell line-derived neurotrophic factor (GDNF) is a neurotrophic factor that has been shown to be a potent survival factor for somatic motor neurons that innervate skeletal muscle.

This study aims to evaluate changes in structural plasticity of motor neurons in the lumbar spinal cord and …

The Impacts Of Aging, Sedentarism, And Exercise On Neurotrophic Factor Expression And Innervation In The Heart And The Effects Of Treatment With Α-Cgrp On Heart Function, Gabriel Almeida Alves

Dissertations

Neurotrophic factors (NFs) are important molecules responsible for development, differentiation, regeneration, and maintenance of new and mature neurons. Neurotrophic factors act as neurocytokines and may assist with the regulation of axonal and dendritic arrangements and synaptic plasticity between neurons themselves or with other non-neural target tissues. In this study, we analyze the levels of two NFs: glial cell line-derived neurotrophic factor (GDNF) and nerve growth factor (NGF). Cardiomyocytes produce these neurotrophic factors which assist with the innervation pattern of the heart. The heart is innervated by the two branches of the autonomic nervous system; namely the sympathetic nervous system and …

Mitochondria Imaging And Targeted Cancer Treatment, Tinghan Zhao

Dissertations

Mitochondria are essential organelles as the site of respiration in eukaryotic cells and are involved in many crucial functions in cell life. Dysfunction of mitochondrial metabolism and irregular morphology have been frequently found in human cancers. The capability of imaging mitochondria as well as regulating their microenvironment is important both scientifically and clinically. Mitochondria penetrating peptides (MPPs), certain peptides that are composed of cationic and hydrophobic amino acids, are good candidates for mitochondria targeting. Herein, a novel MPP, D-argine-phenylalanine-D-argine-phenylalanine-D-argine-phenylalanine-NH₂ (rFrFrF), is conjugated with a rhodamine-based fluorescent chromophore (TAMRA). The TAMRA-rFrFrF probe exhibits advantageous properties for long-term mitochondria tracking of …

A Microbiomic Approach To The Characterization Of The Impacts And Influences Of Viral, Bacterial, And Harmful Algal Bloom Toxins On The Bottlenose Dolphin, Corey David Russo

Dissertations

As apex predators that display high site fidelity Tursiops truncatus (bottlenose dolphin) are indicators of marine ecosystem health. Bottlenose dolphins, additionally, display pathogenesis and immune response similar to that of humans. Humans and coastal bottlenose dolphins, in particular, are constantly exposed to the same industrial, agricultural and domestic toxins and pathogens, contaminants and pollutants. Thus, studies on the bottlenose dolphin are also valuable in bridging the gap between ocean and human health. Bottlenose dolphins are susceptible to viral bacterial and toxin infection. Infection in the bottlenose dolphin manifests itself in the form of mass stranding events, unusual mortality events, chronic …

Role Of Msa In Immune Evasion, Persistence, And Protease Regulation In The Human Pathogenic Strains Of Staphylococcus Aureus, Maria Deepa Basco

Dissertations

Opportunistic pathogens like Staphylococcus aureus on entering the host can stay colonized at the foci of infection or evade the immune system to disseminate to other sites. In this study we investigated the regulatory influence of the modulator of sarA (msa) on immune evasion and host persistence, employing the hospital-acquired strain S. aureus UAMS-1 and community-acquired strain S. aureus USA300 LAC. In the murine sepsis model, mutation of the msa gene in LAC showed no change in dissemination of infection; however, in UAMS-1 a decrease in microbial load was observed in the lungs. Differential regulation by the msa gene was …

Discovery And Characterization Of A Tanapoxvirus Encoded Human Neuregulin Mimetic, David Jeng

Dissertations

Studies on large dsDNA viruses such as poxviruses have been helpful in identifying a number of viral and cellular growth factors that contribute to our broad understanding of virus-host interaction. Orthopoxviruses and leporipoxviruses are among the most studied viruses in this aspect. However, tanapoxvirus (TPV) a member of the genus Yatapoxvirus, still remains largely unexplored, as the only known hosts for this virus are humans and monkeys. Here, we describe the initial characterization of an EGF-like growth factor mimicking human neuregulin from TPV, expressed by the TPV-15L gene. Assays using a baculovirus expressed and tagged TPV-15L protein demonstrated the ability …

Neuroprotective Effects Of A Nicotinic Acetylcholine Receptor Agonist And Modulator In The Rodent Retina, Kazuhiro Iwamoto

Dissertations

The purpose of this dissertation is to assess the potential neuroprotective effect of an alpha7 nAChR agonist, PNU-282987, and modulator, PNU-120596, in an in vitro model of excitotoxicity and an in vivo model of acute glaucoma. In in vitro studies, retinas obtained from Long Evans rats were cultured using various concentrations of the PNU compounds to analyze neuroprotection against glutamate-induced excitotoxicity. After 3 days in culture, RGCs were identified using an antibody against Thy 1.1, visualized using a fluorescent dye and quantified. In culture, glutamate significantly decreased the number of RGCs. However, if either PNU compound was introduced before the …

The Role Of Msa In The Global Regulation Of Virulence In Staphylococcus Aureus, Vijayaraj Nagarajan

Dissertations

Staphylococcus aureus is an important pathogen causing life threatening diseases in humans. Previously we showed that msa modulates the activity of sarA (Staphylococcal accessory regulator), which is one of a major global regulator of virulence in S. aureus. The objective of this study is to characterize the role of msa (Modulator of SarA) in the global regulation of virulence in S. aureus. Structure and function predictions were done using several computational tools and approaches to understand the nature of msa. A novel S. aureus microarray meta-database (SAMMD) was designed and developed to compare and contrast other transcriptomes with msa transcriptome. …

Use Of Monoclonal ∆-9-Tetrahydrocannabinol Antibodies Chemically Bound To A Polystyrene Surface Using Glutaraldehyde For The Purpose Of Extracting ∆-9-Tetrahydrocannabinol And ∆-9-Tetrahydrocannabinol Carboxylic Acid From Postmortem Whole Blood Samples For Analysis By Gas Chromatography Mass Spectrometry, Thomas Sidney Pittman

Dissertations

Quantitations of drugs and their respective metabolites in postmortem blood samples using gas chromatographic instrumentation is a primary analytical practice used to determine if drugs played a role in or were the cause of a victim's death. Postmortem blood samples often prove difficult to work with due to interfering substances formed during the putrefaction process. Attempts to eliminate interfering substances with present day extraction methods can be time-consuming, costly and often ineffective when dealing with drugs that exhibit toxicity or impairment at very low concentrations. This study was conducted using monoclonal antibodies chemically bound to a polystyrene surface to extract …

A Study Of The Environmental Aspects Of Schistosomiasis In Libya, Abubaker I. Swehli

Dissertations

Schistosomiasis is a serious disease in humans. Two species of schistosome, Schistosoma mansoni and Schistosoma haematobium, organisms that cause the disease, parasitize humans in Libya. Schistosomes require aquatic snails in their life cycle. The purpose of this study was to investigate the environmental and the host relationships of the disease in the three regions of Libya where the disease is found. These relationships include:

1) Analyses of the physical-chemical characteristics of the aquatic habitat.

2) Collection of snails to determine: a) the kind of snail species and th e ir abundance; and b) the cercarial infestation rates.

3) Infection rates …