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Medical Sciences Commons

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2007

Doctor of Philosophy (PhD) Heersink School of Medicine

Articles 31 - 39 of 39

Full-Text Articles in Medical Sciences

Directing Akt And Gsk3ss: Molecular Insights Into Cell Signaling And Survival, Gordon P. Meares Jan 2007

Directing Akt And Gsk3ss: Molecular Insights Into Cell Signaling And Survival, Gordon P. Meares

All ETDs from UAB

Proper regulation of survival signaling is critical for all organisms. One important signaling cascade involved in the coordinated effort to control signals influencing cell fate is the phosphatidylinositol 3-kinase (PI3K)-Akt-glycogen synthase kinase 3β (GSK3β) signaling cascade. Following activation by growth factors the PI3K-Akt pathway promotes cell survival and, cell death is facilitated following inhibition of Akt. Many factors influence the function of the Akt-GSK3β signaling dyad, including phosphorylation, protein complex formation and subcellular localization. Previous work had demonstrated that the 90kDa heat shock protein, HSP90, directly binds and stabilizes Akt. Furthermore, several heat shock proteins including HSP90 and HSP105 can …


The Function Of Hiv-1 A-Loop On Primer Selection, Na Ni Jan 2007

The Function Of Hiv-1 A-Loop On Primer Selection, Na Ni

All ETDs from UAB

Reverse transcription is the hallmark of retroviruses, such as HIV-1. A cellular tRNA bound to the primer binding site region (PBS) is used for initiation of reverse transcription. HIV-1 specially selects tRNALys3 as primer, although changing the PBS can force HIV-1 to use alternative tRNAs as a primer. However, HIV-1 reverts back to use tRNALys3 following in vitro replication. The A-loop, located upstream of PBS, interacts with the anti-codon of primer tRNA. The inclusion of A-loop modification has been shown to stabilize the utilization of some alternative tRNAs. The studies in this dissertation focus on further defining the role of …


Regulation Of Vertebrate Gastrulation By Erbb Signaling, Shuyi Nie Jan 2007

Regulation Of Vertebrate Gastrulation By Erbb Signaling, Shuyi Nie

All ETDs from UAB

ErbB receptor tyrosine kinases have long been implicated in cancer formation and progression by regulating cell division, migration, and survival. ErbBs are also essential in multiple processes during invertebrate development; however, their activities during vertebrate embryogenesis are not well understood. For functional characterization of ErbB signaling during vertebrate development, frog model Xenopus laevis was used in our studies. The expression pattern and the general activities of ErbB receptors during early frog development were first analyzed and results shown that ErbBs regulate gastrulation, somite organization and head patterning. As gastrulation is the first major morphogenetic event in vertebrate development, I focused …


Trafficking Of Hantaviral Nucleocapsid Proteins, Harish N. Ramanathan Jan 2007

Trafficking Of Hantaviral Nucleocapsid Proteins, Harish N. Ramanathan

All ETDs from UAB

Hantaviruses are enveloped, negative-sense RNA viruses belonging to genus Hantavirus, within the family Bunyaviridae. Hantaviruses include many serious human pathogens and are classified as Old and New World based on the geographic distribution of rodent reservoirs and their ability to in induce distinct illnesses in humans. Currently there are no reservoirs known for hantaviruses other than the rodents. Human transmission of hantaviruses occurs via inhalation of aerosolized rodent excreta leading to hemorrhagic fever with renal syndrome (HFRS) or hantavirus pulmonary syndrome (HPS). Hantavirus genome consists of small (S), medium (M) and large (L) segments that encode nucleocapsid (N) protein, two …


The Role Of Complement In Experimental Autoimmune Uveitis, Russell W. Read Jan 2007

The Role Of Complement In Experimental Autoimmune Uveitis, Russell W. Read

All ETDs from UAB

The complement system has been increasingly implicated in the pathophysiology of autoimmune disease. Complement expression in the normal human eye had not been previously completely defined. We performed immunohistochemical studies for membrane complement proteins in normal human retina to provide a baseline for future studies. We found expression of the anaphylatoxin receptors, CD55, and CD59 in the inner retina and CD46 in a polarized fashion on the retinal pigment epithelium. Previous studies in uveitis have shown activated fragments of complement in human eyes with uveitis and animal models have shown an effect on disease by complement depletion with cobra venom …


In Vivo Imaging Studies In Animal Models Of Myocardial Infarction With And Without Cell Injections, Balazs Ruzsics Jan 2007

In Vivo Imaging Studies In Animal Models Of Myocardial Infarction With And Without Cell Injections, Balazs Ruzsics

All ETDs from UAB

After prolonged myocardial ischemia, myocardial infarction occurs. Several tissue changes are associated with myocardial infarction and iron labeled cell injections. In the present thesis our major aim was to develop methods to monitor these tissue changes with MRI and MDCT. In the first chapter we used transendocardial injection to deliver iron labeled allogen skeletal myoblasts one week after myocardial infarction. Our goal was to identify the cells and/or injection sites in the myocardium. We used our new Tissue Characterization Mapping method to delineate tissue edema and hemorrhage in the myocardium. The T2 weighted signal intensity enhancement, T2w SIE region was …


Bacillus Anthracis Spore-Host Interactions, Melissa K. Swiecki Jan 2007

Bacillus Anthracis Spore-Host Interactions, Melissa K. Swiecki

All ETDs from UAB

The use of Bacillus anthracis as a bioweapon depends on the dispersal of its spores into the environment, entrance into the body, spore uptake by human host cells, germination of the spores in the host and the pathological consequences of the virulence factors produced by the vegetative cells. Prior to 2001, very little was known about the mechanisms of spore entry into the host, including targeting cell types at airway, digestive and skin surfaces, potential spore receptors on these cells and spore encounters with cellular and humoral elements of the innate and adaptive immune systems. To this end, we have …


The Role Of Cd5 In Experimental Autoimmune Encephalitomyelitis, Robert C. Axtell Jan 2007

The Role Of Cd5 In Experimental Autoimmune Encephalitomyelitis, Robert C. Axtell

All ETDs from UAB

The regulation of activation, differentiation and persistence of effector T-cells are critical for the development of Experimental Autoimmune Encephalomyelitis (EAE), the animal model of Multiple Sclerosis. Until now, the function of CD5 was accepted to be a negative regulator of T-cell activation. This dissertation reports that CD5 has an addi-tional role in T-cell responses, which is to promote cell survival. Observations from EAE experiments revealed that mice deficient in CD5 exhibited decreased disease severity which was associated with the inability of activated T-cells to survive. Moreover, block-ing the engagement of CD5 in mice led to enhanced activation induced cell death …


Primer Selection Of E. Coli Trna Lys,3 By Human Immunodeficiency Virus Type-1, Anna Mcculley Jan 2007

Primer Selection Of E. Coli Trna Lys,3 By Human Immunodeficiency Virus Type-1, Anna Mcculley

All ETDs from UAB

Human immunodeficiency virus (HIV) is the cause of acquired immunodeficiency syndrome (AIDS). HIV replication includes the notable process of reverse transcription, a conversion of RNA to DNA. Reverse transcription is initiated from a primer by a viral enzyme, reverse transcriptase. The primer, tRNALys,3, is selected from the cytoplasm of an infected cell, annealed via the 3’ terminal 18-nucleotides to the viral primer binding site (PBS), and used in a subsequent infection. The mechanism of primer selection has not been determined although numerous studies have been performed. This has been hampered by the challenge of tRNALys,3 manipulation in the cell and …