Molecular Biology Commons^™

Investigating The Functional Role Of Tick Antioxidants In Hematophagy And Vector Competence, Deepak Kumar

Dissertations

Ticks are obligate hematophagous arthropods and harbor several pathogens which transmit various diseases to humans and their domesticated animals. Host blood- digestion in a tick midgut (MG) generates several reactive oxygen species (ROS), which are extremely toxic to essential macromolecules (e.g. DNA, proteins, and lipids) within the cell, resulting in high oxidative stress. Thus, this dissertation focuses on the questions of how tick homeostasis responds to high oxidative stress, and how ticks and their harbored pathogens survive the high surge of oxidative stress during blood digestion. We are specifically interested in the tick-pathogen, Rickettsia parkeri (R. parkeri, Rp), harbored by …

Characterization Of Glycine Rich Proteins From The Salivary Glands Of The Lone Star Tick Amblyomma Americanum, Rebekah Lynn Bullard

Dissertations

Ticks are blood sucking arthropods that feed on living hosts for up to three weeks. The ticks secrete a multitude of pharmacologically active proteins into the host during feeding which allow the tick to avoid the host immune response, establish a blood pool, and form a firm attachment. The firm attachment is facilitated by the formation of a cement cone which surrounds the tick mouthparts and intertwine between the host skin layers. In this study, gene expression of 44 A. americanum genes was measured throughout the bloodmeal to reveal the differential expression of these genes. Each of the genes tested …

The Role Of Foxo Transcription Factors In Alcohol-Induced Deficient Fracture Repair, Philip M. Roper

Dissertations

Proper and complete repair of a bone fracture is essential in quality of life maintenance, but poor healing and fracture malunion are still medically and socially relevant problems. Alcohol abuse impairs normal fracture healing, leading to delayed or incomplete union. This dissertation aims to clarify mechanisms behind this alcohol-induced impaired healing, thereby elucidating potential methods of intervention.

Alcohol-induced oxidative stress has been linked to many morbidities associated with alcohol abuse. This dissertation elucidates a potential mechanism through which alcohol inhibits fracture healing by increasing oxidative stress. Using a rodent model, I found that alcohol exposure decreases fracture callus formation and …

The Role Of Microrna In Cardioprotection: Ischemic Preconditioning And Mesenchymal Stem Cell Paracrine Effects, Kristin Luther

Dissertations

Changes in gene expression and protein levels are an important aspect of cardioprotection in which short non-coding RNA known as miRNA may play a key regulatory role. We investigated the functions of several miRNAs in the context of two cardioprotective stimuli, ischemic preconditioning (IPC) and mesenchymal stem cell (MSC) paracrine effects. We hypothesized that downregulation of a set of miRNAs (miR-148a/b, miR-30b, and let-7a*) augments expression of protective heat shock proteins during IPC, and that MSC exosomes transfer miR-21 to cardiomyocytes, resulting in downregulation of pro-apoptotic genes and reduction of infarct size.

IPC increased the level of Hsp70, Hsp90, and …