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Identification And Characterization Of Distinct Populations Of Clonogenic Bone Marrow Stromal Cells Capable Of Transferring The Hematopoietic Microenvironment In Vivo And Supporting Lt-Hscs In Vitro, Colby Suire

Dissertations and Theses (Open Access)

Bone marrow (BM) stromal cells are ascribed two key functions, 1) stem cells for non-hematopoietic tissues (MSC) and 2) as components of the hematopoietic stem cell niche. Current approaches studying the stromal cell system in the mouse are complicated by the low yield of clonogenic progenitors (CFU-F). Given the perivascular location of MSC in BM, we developed an alternative methodology to isolate MSC from mBM. An intact ‘plug’ of bone marrow is expelled from bones and enzymatically disaggregated to yield a single cell suspension. The recovery of CFU-F (1917.95+199) reproducibly exceeds that obtained using the standard BM flushing technique (14.32+1.9) …

Lmw-E Mediates Mammary Tumorigenesis By Deregulating Acinar Morphogenesis & Generating Cancer Stem Cells, Mylinh T. Duong

Dissertations and Theses (Open Access)

Cyclin E is the regulatory subunit of the cyclin E/CDK2 complex that

mediates the G1-S phase transition. N-terminal cleavage of cyclin E by elastase in

breast cancer generates two low molecular weight (LMW) isoforms that exhibit both

enhanced kinase activity and resistance to p21 and p27 inhibition compared to fulllength cyclin E. Clinically, approximately 27% of breast cancer patients overexpress

LMW-E and associate with poor survival. Therefore, we hypothesize that LMW-E

disrupts normal mammary acinar morphogenesis and serves as the initial route into

breast tumor development. We first demonstrate that LMW-E overexpression in

non-tumorigenic hMECs is sufficient to induce tumor …

Understanding The Roles Of Non-Homologous End Joining And P53 After Dna Damage, Omid Tavana

Dissertations and Theses (Open Access)

The inability to maintain genomic stability and control proliferation are hallmarks of many cancers, which become exacerbated in the presence of unrepaired DNA damage. Such genotoxic stresses trigger the p53 tumor suppressor network to activate transient cell cycle arrest allowing for DNA repair; if the damage is excessive or irreparable, apoptosis or cellular senescence is triggered. One of the major DNA repair pathway that mends DNA double strand breaks is non-homologous end joining (NHEJ). Abrogating the NHEJ pathway leads to an accumulation of DNA damage in the lymphoid system that triggers p53-mediated apoptosis; complete deletion of p53 in this system …

Taz As A Regulator Of Mesenchymal Transformation And Clinical Aggressiveness In Gliomas, Katrina Salazar

Dissertations and Theses (Open Access)

Glioblastoma multiforme (GBM) is an aggressive, high grade brain tumor. Microarray studies have shown a subset of GBMs with a mesenchymal gene signature. This subset is associated with poor clinical outcome and resistance to treatment. To establish the molecular drivers of this mesenchymal transition, we correlated transcription factor expression to the mesenchymal signature and identified transcriptional co-activator with PDZ-binding motif (TAZ) to be highly associated with the mesenchymal shift. High TAZ expression correlated with worse clinical outcome and higher grade. These data led to the hypothesis that TAZ is critical to the mesenchymal transition and aggressive clinical behavior seen in …

Regulation Of Net1a Subcellular Localization By The Small Gtpase Rac1, Christopher A. Morris

Dissertations and Theses (Open Access)

Activation of Rho family small G proteins is thought to be a critical event in breast cancer development and metastatic progression. Rho protein activation is stimulated by a family of enzymes known as guanine nucleotide exchange factors (Rho GEFs). The neuroepithelioma transforming gene 1 (Net1) is a Rho GEF specific for the RhoA subfamily that is overexpressed in primary breast tumors and breast cancer cell lines. Net1 isoform expression is also required for migration and invasion of breast cancer cells in vitro. These data indicate that Net1 may be a critical regulator of metastatic progression in breast cancer. Net1 activity …

Bim Mediates Imatinib-Induced Apoptosis Of Gastrointestinal Stromal Tumors: Translational Implications, David Reynoso

Dissertations and Theses (Open Access)

Gastrointestinal stromal tumors (GISTs) are oncogene-addicted cancers driven by activating mutations in the genes encoding receptor tyrosine kinases KIT and PDGFR-α. Imatinib mesylate, a specific inhibitor of KIT and PDGFR-α signaling, delays progression of GIST, but is incapable of achieving cure. Thus, most patients who initially respond to imatinib therapy eventually experience tumor progression, and have limited therapeutic options thereafter. To address imatinib-resistance and tumor progression, these studies sought to understand the molecular mechanisms that regulate apoptosis in GIST, and evaluate combination therapies that kill GISTs cells via complementary, but independent, mechanisms. BIM (Bcl-2 interacting mediator …

Metabolic Regulation Of Mtor Activation And Endoplasmic Reticulum Stress In The Heart, Shiraj Sen

Dissertations and Theses (Open Access)

When subjected to increased workload, the heart responds metabolically by increasing its reliance on glucose and structurally by increasing the size of myocytes. Whether changes in metabolism regulate the structural remodeling process is unknown. A likely candidate for a link between metabolism and growth in the heart is the mammalian target of rapamycin (mTOR), which couples energy and nutrient metabolism to cell growth. Recently, sustained mTOR activation has also been implicated in the development of endoplasmic reticulum (ER) stress. We explored possible mechanisms by which acute metabolic changes in the hemodynamically stressed heart regulate mTOR activation, ER stress and cardiac …

Induced-Pluripotent Stem-Derived Neuronal Progenitor Cells As A Novel Treatment For Neurodegenerative Diseases, Dennisse A. Gonzalez-Romero

Dissertations and Theses (Open Access)

Cellular therapies, as neuronal progenitor (NP) cells grafting, are promising therapies for patients affected with neurodegenerative diseases like Creutzfeldt-Jakob Disease (CJD). At this time there is no effective treatment or cure for CJD. The disease is inevitably fatal and affected people usually die within months of the appearance of the first clinical symptoms. Compelling evidence indicate that the hallmark event in the disease is the conversion of the normal prion protein (termed PrP^C) into the disease-associated, misfolded form (called PrP^Sc). Thus, a reasonable therapeutic target would be to prevent PrP misfolding and prion replication. This strategy …

Population Coding In Laminar Cortical Circuits, Bryan J. Hansen

Dissertations and Theses (Open Access)

One of the fundamental questions in neuroscience is to understand how encoding of sensory inputs is distributed across neuronal networks in cerebral cortex to influence sensory processing and behavioral performance. The fact that the structure of neuronal networks is organized according to cortical layers raises the possibility that sensory information could be processed differently in distinct layers. The goal of my thesis research is to understand how laminar circuits encode information in their population activity, how the properties of the population code adapt to changes in visual input, and how population coding influences behavioral performance. To this end, we performed …

Genetic Predictors Of Hyperglycemia Due To Hydrochlorothiazide Therapy, Jorge L. Del Aguila

Dissertations and Theses (Open Access)

Response to pharmacological treatment is variable among individuals. Some patients respond favorably to a drug while others develop adverse reactions. Early investigations showed evidence of variation in genes that code for drug receptors, drug transporters, and drug metabolizing enzymes; and pharmacogenetics appeared as the science that studies the relationship between drug response and genetic variation.

Thiazide diuretics are the recommended first-line monotherapy for hypertension (i.e. SBP>140 or DBP>90). Even so, diuretics are associated with adverse metabolic side effects, such as hyperglycemia, which increase the risk of developing type 2 diabetes. Published approaches testing variation in candidate genes (e.g. …

Functional Characterization Of Atxa, The Bacillus Anthracis Virulence Regulator, Troy G. Hammerstrom

Dissertations and Theses (Open Access)

Coordinated expression of virulence genes in Bacillus anthracis occurs via a multi-faceted signal transduction pathway that is dependent upon the AtxA protein. Intricate control of atxA gene transcription and AtxA protein function have become apparent from studies of AtxA-induced synthesis of the anthrax toxin proteins and the poly-D-glutamic acid capsule, two factors with important roles in B. anthracis pathogenesis. The amino-terminal region of the AtxA protein contains winged-helix (WH) and helix-turn-helix (HTH) motifs, structural features associated with DNA-binding. Using filter binding assays, I determined that AtxA interacted non-specifically at a low nanomolar affinity with a target promoter (Plef) …

Effects Of Thymus Size And Involution On The Contribution Of Recent Thymic Emigrants To The Peripheral T Cell Pool, Michelle L. Bolner

Dissertations and Theses (Open Access)

The contribution of recent thymic emigrants (RTEs) to the peripheral naïve T cell population is necessary to maintain diversity of the T cell receptor (TCR) repertoire and produce immune responses against newly encountered antigens.

The thymus involutes with age, after irradiation or chemotherapy, and due to severe viral infections. Thymus involution results in decreased thymopoiesis and RTE output leading to a reduced diversity of peripheral T cells. This increases susceptibility to disease and impairs immune responsiveness to vaccines. Therefore, studies aimed at maintaining or regenerating thymic function are integral for maintaining and restoring peripheral TCR diversity.

Mice that express a …

Increased Geranylgeranylated K-Ras Contributes To Antineoplastic Effects Of Farnesyltransferase Inhibitors., Mandy A. Hall

Dissertations and Theses (Open Access)

The Ras family of small GTPases (N-, H-, and K-Ras) is a group of important signaling mediators. Ras is frequently activated in some cancers, while others maintain low level activity to achieve optimal cell growth. In cells with endogenously low levels of active Ras, increasing Ras signaling through the ERK and p38 MAPK pathways can cause growth arrest or cell death. Ras requires prenylation – the addition of a 15-carbon (farnesyl) or 20-carbon (geranylgeranyl) group – to keep the protein anchored into membranes for effective signaling. N- and K-Ras can be alternatively geranylgeranylated (GG’d) if farnesylation is inhibited but are …

Cellular Trafficking Of Single And Multistage Vectors, Silvia Ferrati

Dissertations and Theses (Open Access)

Nanomedicine is an innovative field of science which has recently generated many drug delivery platforms with exciting results. The great potential of these strategies rely on the unique characteristics of the devices at the nano-scale in terms of long time circulation in the blood stream, selective accumulation at the lesions sites, increased solubility in aqueous solutions, etc.

Herein we report on a new drug delivery system known as a multistage system which is comprised of non-spherical, mesoporous silicon particles loaded with second stage nanoparticles. The rationally designed particle shape, the possibility to modulate the surface properties and the degree of …

Novel Phantoms And Post-Processing For Diffusion Spectrum Imaging, Vaibhav Juneja

Dissertations and Theses (Open Access)

High Angular Resolution Diffusion Imaging (HARDI) techniques, including Diffusion Spectrum Imaging (DSI), have been proposed to resolve crossing and other complex fiber architecture in the human brain white matter. In these methods, directional information of diffusion is inferred from the peaks in the orientation distribution function (ODF). Extensive studies using histology on macaque brain, cat cerebellum, rat hippocampus and optic tracts, and bovine tongue are qualitatively in agreement with the DSI-derived ODFs and tractography. However, there are only two studies in the literature which validated the DSI results using physical phantoms and both these studies were not performed on a …

Accuracy Of The Brcapro Risk Assessment Model In Males Presenting To Md Anderson For Brca Testing, Carolyn Garby, Banu Arun M.D, Michelle Jackson M.S., Cgc, Jennifer Litton M.D, Syed Hashmi M.D., Ph.D, Sharon Giordano M.D, Mph, Claire Singletary M.S, Cgc

Dissertations and Theses (Open Access)

ACCURACY OF THE BRCAPRO RISK ASSESSMENT MODEL IN MALES PRESENTING TO MD ANDERSON FOR BRCA TESTING

Publication No. _______

Carolyn A. Garby, B.S.

Supervisory Professor: Banu Arun, M.D.

Hereditary Breast and Ovarian Cancer (HBOC) syndrome is due to mutations in BRCA1 and BRCA2 genes. Women with HBOC have high risks to develop breast and ovarian cancers. Males with HBOC are commonly overlooked because male breast cancer is rare and other male cancer risks such as prostate and pancreatic cancers are relatively low. BRCA genetic testing is indicated for men as it is currently estimated that 4-40% of male breast cancers …

Regulation Of Protein Degradation In The Heart By Amp-Activated Protein Kinase, Kedryn K. Baskin

Dissertations and Theses (Open Access)

The degradation of proteins by the ubiquitin proteasome system is essential for cellular homeostasis in the heart. An important regulator of metabolic homeostasis is AMP-activated protein kinase (AMPK). During nutrient deprivation, AMPK is activated and intracellular proteolysis is enhanced through the ubiquitin proteasome system (UPS). Whether AMPK plays a role in protein degradation through the UPS in the heart is not known. Here I present data in support of the hypothesis that AMPK transcriptionally regulates key players in the UPS, which, under extreme conditions can be detrimental to the heart. The ubiquitin ligases MAFbx /Atrogin-1 and MuRF1, key regulators of …

Predictors Of Contralateral Breast Cancer In Brca Negative Women, Ann E. Simmons

Dissertations and Theses (Open Access)

Breast cancer is the most common cancer diagnosis and second leading cause of death in women. Risk factors associated with breast cancer include: increased age, alcohol consumption, cigarette smoking, white race, physical inactivity, benign breast conditions, reproductive and hormonal factors, dietary factors, and family history. Hereditary breast and ovarian cancer syndrome (HBOC) is caused by mutations in the BRCA1 and BRCA2 genes. Women carrying a mutation in these genes are at an increased risk to develop a second breast cancer. Contralateral breast cancer is the most common second primary cancer in patients treated for a first breast cancer. Other risk …

Chemosensitization Of Hepatocellular Carcinoma To Gemcitabine By Non-Invasive Radiofrequency Field-Induced Hyperthermia, Mustafa Raoof

Dissertations and Theses (Open Access)

Gemcitabine is a potent nucleoside analogue against solid tumors however drug resistance rapidly emerges. Removal of gemcitabine incorporated in the DNA by repair mechanisms could potentially contribute to resistance in chemo-refractory solid tumors. In this study, we evaluated homologous recombination repair of gemcitabine-stalled replication forks as a potential mechanism contributing to resistance. We also studied the effect of hyperthermia on homologous recombination pathway to explain the previously reported synergy between gemcitabine and hyperthermia. We found that hyperthermia degrades and inhibits localization of Mre11 to gemcitabine-stalled replication forks. Furthermore, gemcitabine-treated cells that were also treated with hyperthermia demonstrate a prolonged passage …

A Pre-Clinical Assessment Of Minocycline For Treatment Of Chronic Neuropathic Pain After Spinal Cord Injury, Alissa R. Poteete

Dissertations and Theses (Open Access)

Patients living with a spinal cord injury (SCI) often develop chronic neuropathic pain (CNP). Unfortunately, the clinically approved, current standard of treatment, gabapentin, only provides temporary pain relief. This treatment can cause numerous adverse side effects that negatively affect the daily lives of SCI patients. There is a great need for alternative, effective treatments for SCI-dependent CNP.

Minocycline, an FDA-approved antibiotic, has been widely prescribed for the treatment of acne for several decades. However, recent studies demonstrate that minocycline has neuroprotective properties in several pre-clinical rodent models of CNS trauma and disease. Pre-clinical studies also show that short-term minocycline treatment …

Pathologic Markers Of Prognosis In Ampullary Carcinoma, Rachna T. Shroff

Dissertations and Theses (Open Access)

Ampullary cancer is a rare gastrointestinal malignancy that can be curable with surgical resection of localized disease. The benefit of adjuvant therapy, however, remains unknown in these patients partly because of difficulty in stratifying which patients are at high risk for recurrence. To better identify those patients who may benefit from adjuvant therapy, I conducted a retrospective analysis the pathology reports from 176 patients with surgically resected ampullary cancer who had not received any neoadjuvant therapy, the systemic therapy given, and the patient outcomes. A tissue microarray (TMA) of 95 surgically resected ampullary specimens was also constructed to examine whether …

Evidence Of Human Endogenous Retrovirus K Involvement In Human Cancer, Joshua B. Plummer

Dissertations and Theses (Open Access)

Many lines of clinical and experimental evidence indicate a viral role in carcinogenesis (1-6). Our access to patient plasma, serum, and tissue samples from invasive breast cancer (N=19), ductal carcinoma

in situ (N=13), malignant ovarian cancer (N=12), and benign ovarian tumors (N=9), via IRB-approved and informed consent protocols through M.D. Anderson Cancer Center, as well as normal donor plasmas purchased from Gulf Coast Regional Blood Center (N=6), has allowed us to survey primary patient blood and tissue samples, healthy donor blood from the general population, as well as commercially available human cell lines for the presence of human endogenous retrovirus …

Regulation Of Protein Degradation In The Heart By Amp-Activated Protein Kinase, Kedryn K. Baskin, Kedryn K. Baskin

Dissertations and Theses (Open Access)

The degradation of proteins by the ubiquitin proteasome system is essential for cellular homeostasis in the heart. An important regulator of metabolic homeostasis is AMP-activated protein kinase (AMPK). During nutrient deprivation, AMPK is activated and intracellular proteolysis is enhanced through the ubiquitin proteasome system (UPS). Whether AMPK plays a role in protein degradation through the UPS in the heart is not known. Here I present data in support of the hypothesis that AMPK transcriptionally regulates key players in the UPS, which, under extreme conditions can be detrimental to the heart. The ubiquitin ligases MAFbx /Atrogin-1 and MuRF1, key regulators of …

Evaluation Of Knowledge Regarding Diagnostic Strategies For Genetic Diseases In Select Residents, Samantha Penney

Dissertations and Theses (Open Access)

Genetics education for physicians has been a popular publication topic in the United States and in Europe for over 20 years. Decreasing numbers of medical genetics professionals and an increasing volume of genetic information has created a dire need for increased genetics training in medical school and in clinical practice. This study aimed to assess how well pediatrics-focused primary care physicians apply their general genetics knowledge to clinical genetic testing using scenario-based questions. We chose to specifically focus on knowledge of the diagnostic applicability of Chromosomal Microarray (CMA) technology in pediatrics because of its recent recommendation by the International Standard …

Control Of The Master Virulence Regulatory Gene Atxa In Bacillus Anthracis, Jennifer L. Dale

Dissertations and Theses (Open Access)

Transcription of the Bacillus anthracis structural genes for the anthrax toxin proteins and biosynthetic operon for capsule are positively regulated by AtxA, a transcription regulator with unique properties. Consistent with the role of atxA in virulence factor expression, a B. anthracis atxA-null mutant is avirulent in a murine model for anthrax. In batch culture, multiple signals impact atxA transcript levels, and the timing and steady state level of atxA expression is critical for optimal toxin and capsule synthesis. Despite the apparent complex control of atxA transcription, only one trans-acting protein, the transition state regulator AbrB, has been demonstrated …

April 25, 2012, Geneva Henry

Lecture Series on E-Science

Geneva Henry, Executive Director of the Center for Digital Scholarship, Rice University. Data rights and ownership of digital research data can impact how you use data, how others use data you've collected, and how rights are determined in collaborative research. Copyright rules governing data vary from one country to the next, making data ownership in international collaborations particularly murky. Licensing the use of data sets from the start is one way to address these issues early and provide a means for easily sharing datasets that can be cited and properly attributed. This talk with introduce issues associated with digital research …

Compliance: E-Science Mandates And Policies, Sarah White

Lecture Series on E-Science

Data collected under federally funded research is subject to compliance rules and regulations. Policies affecting what you can and cannot do with your data, who is responsible, and what role your institution plays can vary with funding agencies and the type of data collected. This talk will address many of the compliance issues associated with research data, as well as funder mandates that you need to be aware of to ensure compliance.

New England Journal Of Medicine And Nature Ipad Applications, Vol.10 (4), Texas Medical Center Library

Insider Express (2003-2013)

No abstract provided.

Gsbs News, Spring 2012, Graduate School Of Biomedical Sciences, University Of Texas Health Science Center At Houston/M.D. Anderson Cancer Center

GSBS News

No abstract provided.

Archivist Philip Montgomery Speaks At International Symposium, Philip Montgomery

Library Staff Publications

No abstract provided.