Life Sciences Commons^™

Utility Of The Motivation To Change Lifestyle And Health Behaviors For Dementia Risk Reduction Scale (Mclhb-Drr) Based On A North American Sample, Angelina E. Witbeck

Dissertations

As the population ages, the prevalence rates of dementia continue to increase. Without a cure or promising treatment for dementia, the best course of lowering the prevalence rates of dementia is through preventative measures. Through an electronic survey, the study utilized the MCLHB-DRR scale to determine whether (1) gender, age, educational background, and socioeconomic status will impact the motivational factors to change lifestyle and health behaviors to reduce the risk of developing dementia and (2) direct experiences with individuals that have a dementia diagnosis are likely to impact one's motivational factors to change lifestyle and health behaviors to reduce the …

Liquid Biopsies For Type 2 Diabetes Mellitus: Biomarkers For Disease Risk And Diagnosis, Stephanie Chidester

Dissertations

Background: Type 2 diabetes mellitus (T2DM) has reached epidemic proportions in the United States. There is a critical need for earlier and more effective screening and diagnostic tools. Innovative liquid biopsy technologies may play a key role in meeting this need. Liquid biopsies are a non-invasive, adjunctive tool for determining diagnosis, prognosis, and therapeutic response. This dissertation focuses on two potential applications of liquid biopsy technologies to T2DM: (1) epigenome-wide association studies to identify epigenetic markers of risk for T2DM, and (2) extracellular vesicle (EV)-based biomarker studies to identify and detect markers associated with T2DM development and progression. Dissertation studies: …

Redefining Burnout: Exploring Common Conceptualizations And The Neurophysiology Of Chronic Stress To Establish An Integrated Allostatic Model, Danny A. Guzzi

Dissertations

Burnout is a widely researched stress-related phenomenon associated with numerous adverse outcomes for employees and organizations. Unfortunately, burnout is not well understood and research to this point has been flawed due to a lack of consensus on the definition, dimensionality, and context of the construct. Prevalent conceptualizations of burnout have been criticized for being arbitrarily developed without solid theoretical foundation and for failing to clearly distinguish burnout from depression or other work-related conditions such as compassion fatigue, secondary traumatization, and vicarious traumatization. The current project first examines relevant literature to identify commonalities among prevalent burnout conceptualizations. Then relevant stress research …

The Influence Of Stressful Life Events On The Development Of Type 2 Diabetes, Joshua Minks

Dissertations

This study examined the relationship between distress and the development of Type 2 diabetes mellitus (T2DM) in the presence of established risk factors. Distress secondary to mental health disparities, stressful life events, and work conditions has been shown to promote insulin resistance and the development of T2DM.

Subjects (N=79) diagnosed with T2DM within the previous six months were recruited from SSM Health Centers and VA Medical Centers in the greater St. Louis area. They completed the Recent Life Changes Questionnaire, ENRICHD Social Support Instrument, and a demographic survey and analyses were conducted to determine differences between the veteran …

Interactions And Pathogen Transmission Between Carnivores In Madagascar, Fidisoa Rasambainarivo

Dissertations

Introduced carnivores exert considerable pressure on native predators through predation, competition and disease transmission. Improved understanding of determinant factors of interactions and pathogen transmission between introduced and endemic wildlife may help to predict disease emergence, avoid pathogen spillover and help control outbreaks. Using non-invasive camera traps, I identified areas where transmission of pathogens might happen through records of shared space-use within a protected area in Eastern Madagascar. I showed that indirect interactions between animals were more likely to occur near the research station which may constitute a disease transmission hotspot for carnivores in the landscape. Secondly, I investigated the associations …

A Novel Role For Osteopontin In Facilitating West Nile Virus Neuroinvasion, Amber M. Paul

Dissertations

West Nile virus (WNV) is a positive-sensed, single-stranded RNA flavivirus that can cause human neuroinvasive diseases, including encephalitis, meningitis, and flaccid paralysis. The mechanisms by which WNV enters the central nervous system and the host-factors that are involved in WNV-neuroinvasiveness are not completely understood. Osteopontin (OPN), a multifunctional glycoprotein, has been implicated as a bio-marker for a number of neuroinflammatory diseases. In particular, secreted (s)OPN has been implicated to participate in recruitment of polymorphonuclear neutrophils (PMN) to sites of its expression, while PMNs have been suggested to act as WNV reservoirs. Therefore, sOPN recruitment of PMNs may contribute to neuroinvasive …

Study Of Rickettsia Parkeri Colonization And Proliferation In The Tick Host Amblyomma Maculatum (Acari: Ixodidae), Khemraj Budachetri

Dissertations

Amblyomma maculatum (Gulf coast tick) ticks are prevalent across the Atlantic to Gulf Coast region of United States. These ticks are recognized vectors of Rickettsia parkeri, a spotted fever group of Rickettsia (SFGR) known to cause American boutonneuse fever associated with fever and eschar rashes localized to the site of bites. We hypothesized that Rickettsia parkeri colonization and proliferation in the tick vector involve pathogen-symbiont dynamics and tick-pathogen interactions, which influence rickettsial transmission to the victims after tick bites. The rickettsial infection is maintained across the tick life cycle for many generations due to transovarial and transstadial transmission of …

Epidemiology Of White Spot Syndrome Virus In The Daggerblade Grass Shrimp (Palaemonetes Pugio) And The Gulf Sand Fiddler Crab (Uca Panacea), Muhammad

Dissertations

Ever since the first outbreaks of White spot syndrome virus (WSSV), which causes White Spot Disease (WSD), in Asia in the early 1990s, the pathogen has been a major constraint to the profitability of the shrimp aquaculture industry across the globe. WSSV has a broad host range and is routinely detected in wild decapod crustaceans. In the present study, two common species in the tidal salt marsh along the northern coast of the Gulf of Mexico, the daggerblade grass shrimp (Palaemonetes pugio) and the Gulf sand fiddler crab (Uca panacea), were investigated for their role as …

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 …

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 …

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. …

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 …