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Full-Text Articles in Medicine and Health Sciences

Chaperone Expression And Effects Of Its Inhibition On Breast Cancer Sensitization, Malissa Diehl Jul 2009

Chaperone Expression And Effects Of Its Inhibition On Breast Cancer Sensitization, Malissa Diehl

Theses and Dissertations

Breast cancer is one of the most prevalent and deadly forms of cancer in women and is not restricted by race or ethnicity. Although a wealth of knowledge has been amassed on the biology of breast cancer, including its risk factors, diagnosis, prognosis, prevention, and treatment, it remains a serious health concern and active area of research. Initial response to standard chemotherapeutic and radiotherapeutic regimens is generally strong for many patients, yet breast tumors often recur, leading to more aggressive and resistant tumors. Because recurrence is such a clinical issue, more effective therapeutic approaches are needed to eliminate partial clinical …


Chaperone Association With Telomere Binding Proteins, Amy Depcrynski Jul 2009

Chaperone Association With Telomere Binding Proteins, Amy Depcrynski

Theses and Dissertations

The Hsp90 chaperone complex associates with the telomerase enzyme, facilitating the assembly of the ribonucleoprotein complex. While previous data from our laboratory indicate that Hsp90 and p23 remain stably associated with (functionally active) telomerase, more recent experiments suggest that these chaperones associate with telomeres independent of telomerase, presumably through a specific interaction with telomere binding proteins. The current study examines the novel interactions between TRF2, TRF1, TIN2 and TPP1 and molecular chaperones (Hsp90, Hsp70, p23). In vitro and in cell experiments have shown an interaction between TRF1 and TRF2 and the molecular chaperones Hsp90 and Hsp70. Inhibition of Hsp90 using …


Exploring The Methylation Status Of Rai1 And The Rai1 Consensus Binding Sequence, Eri Kamura Jul 2009

Exploring The Methylation Status Of Rai1 And The Rai1 Consensus Binding Sequence, Eri Kamura

Theses and Dissertations

Smith Magenis Syndrome (SMS) is a multiple congenital anomalies/ mental retardation disorder caused by deletion or mutation of the RAI1 gene on chromosome 17p11.2. The majority of patients with SMS phenotypes have a deletion or mutation of RAI1. However, some patients have been observed with SMS-like phenotypes and yet have no deletions or mutations in the RAI1 gene. One possible explanation could be aberrant methylation of RAI1 since RAI1 is present and yet may be silenced. In order to study this possibility, patient cell lines were treated with 5-Aza-2’-deoxycytidine. RNA was extracted and real-time PCR was used to check the …


Retinoic Acid Induced 1 Gene Analysis In Humans And Zebrafish, Bijal Vyas Jul 2009

Retinoic Acid Induced 1 Gene Analysis In Humans And Zebrafish, Bijal Vyas

Theses and Dissertations

Smith-Magenis syndrome (SMS) is a complex mental retardation syndrome caused by deletion of 17p11.2 region or mutation of the RAI1 gene (retinoic acid induced 1). Individuals with SMS typically exhibit speech and motor delays, mental retardation, characteristic craniofacial and skeletal anomalies, and a distinct neurobehavioral phenotype that includes sleep disturbances, stereotypes, and maladaptive and self-injurious behaviors. RAI1 is thought to be a transcription factor modulating the expression of genes involved in a variety of cellular functions. Previous studies have shown the RAI1 gene being induced by retinoic acid (RA), a derivative of vitamin A. RA plays a significant role in …


Identification Of Apoptosis Pathway In Treacher Collins Syndrome, Khaled Alsayegh Jun 2009

Identification Of Apoptosis Pathway In Treacher Collins Syndrome, Khaled Alsayegh

Theses and Dissertations

Treacher Collins Syndrome (TCS) is a rare autosomal dominant disorder characterized by severe craniofacial defects. The syndrome is associated with mutations in the TCOF1 gene, which encodes a nucleolar phosphoprotein called treacle. Model organisms have been generated to model the disease and have revealed knowledge about the etiology and pathogenesis of the disorder. The craniofacial abnormality observed in TCS patients is found to be caused by an increased level of apoptosis in the neuroepithelium and from this it has been suggested that treacle is important for proper formation and proliferation of neural crest cells that will ultimately contribute to the …


Roles Of Krüppel Like Factors Klf1, Klf2, And Klf4 In Embryonic Beta-Globin Gene Expression, Yousef Alhashem Jun 2009

Roles Of Krüppel Like Factors Klf1, Klf2, And Klf4 In Embryonic Beta-Globin Gene Expression, Yousef Alhashem

Theses and Dissertations

Krüppel like factors (KLFs) are a family of 17 proteins whose main function is gene regulation by binding to DNA elements in the promoters of various genes. KLF transcription factors recognize CACCC-elements and act as activators or repressors of the gene expression. Among the 17 family members, KLF1, KLF2, and KLF4 share high homology to each other. KLF1 is the founding member of the family and is an erythroid-specific protein. KLF2 is expressed in erythroid, endothelial, and other cells. KLF4 is expressed in endothelial, smooth muscle, and other cells. In this thesis, the functions of these KLFs were reviewed in …


Obesity, Adiposity, And Satiety In Mouse Models Of Smith-Magenis Syndrome And Dup(17)(P11.2) Syndrome, Brooke Burns Apr 2009

Obesity, Adiposity, And Satiety In Mouse Models Of Smith-Magenis Syndrome And Dup(17)(P11.2) Syndrome, Brooke Burns

Theses and Dissertations

Smith-Magenis syndrome (SMS) is a complex disorder caused by haploinsufficiency of RAI1 and characterized by sleep disturbances, behavioral abnormalities, mental retardation, and obesity in teens and adults. Rai1+/- mice are obese after 20 weeks. Dup(17)(p11.2) syndrome is a complex disorder associated with overexpression of RAI1. A transgenic mouse model of dup(17)(p11.2) syndrome overexpresses Rai1 and results in a mouse that is growth delayed. In order to characterize the obese phenotypes of mouse models of SMS and the role of RAI1 in obesity, daily food intake and serum levels of insulin, glucose, PPY, and leptin were measured; adiposity was studied by …


Effects Of Altered Superoxide Dismutase Expression On Age-Related Functional Declines And Survival In Drosophila, Ian Martin Apr 2008

Effects Of Altered Superoxide Dismutase Expression On Age-Related Functional Declines And Survival In Drosophila, Ian Martin

Theses and Dissertations

Most organisms experience progressive declines in physiological function as they age. A number of studies in a variety of species support a strong link between oxidative damage, age-related functional declines and life span determination. Here, manipulating the expression levels of superoxide dismutase (SOD) isoenzymes SOD1 and SOD2, resulted in altered functional senescence and survival characteristics in Drosophila. Overexpression of cytosolic Sod1 using the yeast GAL4/UAS system conferred a 30-34% increase in mean life span and resulted in an attenuated senescence of odor avoidance behavior in aging flies. Tissue-specific Sod1 overexpression selectively in the nervous system or muscle failed to reproduce …


Telomerase Inhibition And Sensitization Of Breast Tumor Cells, Kennon R. Poynter Jan 2007

Telomerase Inhibition And Sensitization Of Breast Tumor Cells, Kennon R. Poynter

Theses and Dissertations

Telomerase, a ribonucleoprotein enzyme minimally composed of an RNA template (hTR) and a catalytically active protein subunit (hTERT), synthesizes telomeric repeats onto chromosome ends and is obligatory for continuous tumor cell proliferation, as well as malignant progression of breast cancer cells. Telomerase is an attractive anticancer therapeutic target because its activity is present in over 90% of human cancers, including more than 95% of breast carcinomas, but undetectable in most somatic cells. Traditions chemo- and radio-therapies lack the ability to effectively control and cure breast cancer, in part because residual cells are or become resistant to DNA damaging modalities.While various …


The Quantitative Genetics Of Neurodevelopment: A Magnetic Resonance Imaging Study Of Childhood And Adolescence, James Eric Schmitt Jan 2007

The Quantitative Genetics Of Neurodevelopment: A Magnetic Resonance Imaging Study Of Childhood And Adolescence, James Eric Schmitt

Theses and Dissertations

Understanding the causes of individual differences in brain structure may give clues about the etiology of cognition, personality, and psychopathology, and also may identify endophenotypes for molecular genetic studies on brain development. We performed a comprehensive statistical genetic study of anatomic neuroimaging data from a large pediatric sample (N=600+) of twins and family members from the Child Psychiatry Branch at the NIMH. These analyses included variance decomposition of structural volumetric endophenotypes at several levels of resolution, voxel-level analysis of cortical thickness, assessment of gene by age interaction, several multivariate genetic analyses, and a search for genetically-mediated brain-behavioral relationships. These analyses …


Dual Regulation Of Telomerase Activity By Hsf1 And Its Role In Prostate Cancer Progression, Keith Douglas Ostergaard Jensen Jan 2006

Dual Regulation Of Telomerase Activity By Hsf1 And Its Role In Prostate Cancer Progression, Keith Douglas Ostergaard Jensen

Theses and Dissertations

It has been shown that the key components of the hsp90 chaperone complex, including hsp90, p23, hsp70, hsp40, and HOP (p60), associate with telomerase; however, their specific roles in telomerase function and tumor progression have not yet been defined. HSF1, the primary mammalian heat shock protein transcription factor, may affect telomerase activity and transformation by regulating the expression of several hsp90 chaperone complex proteins in response to stress as well as regulating the transcription of hTERT, the protein subunit of telomerase.In our in vitro model of prostate cancer progression, as cells progress from immortal but non-tumorigenic (P69) to tumorigenic (M2182) …


A Critical Review Of Telomerase Biology And Model Systems For The Study Of Telomerase, Jeremy Charles Aisenberg Jan 2006

A Critical Review Of Telomerase Biology And Model Systems For The Study Of Telomerase, Jeremy Charles Aisenberg

Theses and Dissertations

The study of telomere and telomerase biology holds substantial promise in uncovering the molecular process of aging and the treatment of cancers. Studies have shown that telomere shortening is directly linked to cellular aging and that telomerase expression is found in over 85% of human cancers, including 95% of all advanced malignancies. Development of effective model systems to elucidate the molecular mechanisms underlying the role of telomeres and telomerase in the processes aging and cancer is of particular importance. While inbred strains of mice have provided a wealth of information for a variety of pathways and diseases, the mouse model …


Characterization Of The Tcof1 Gene Using A Neuroblastoma Cell Line And A Mouse Model, Lin Li Jan 2006

Characterization Of The Tcof1 Gene Using A Neuroblastoma Cell Line And A Mouse Model, Lin Li

Theses and Dissertations

Treacher Collins syndrome (TCS) is an autosomal dominant craniofacial development disorder and is caused by mutations in the TCOF1 gene. The TCOFl protein treacle is a nucleolar protein and may function in ribosome biogenesis.Previously, we identified downstream candidate genes using microarray analysis after manipulating Tcofl levels in a murine neuroblastoma (NB) cell line. The list of genes includes cell cycle genes as well as the transcription factors Cnbp and Tbx2, which are known to affect the cell cycle through the c-myc and p19-Mdm2-p53-p21 pathways respectively. To further characterize the cellular effects of Tcofl, stably transfected NB cell lines with overexpression …


A Twin Study Of Antisocial Behavior And Depression: Methodology, Etiology, And Comorbidity, Kelly A. Tracy Jan 2006

A Twin Study Of Antisocial Behavior And Depression: Methodology, Etiology, And Comorbidity, Kelly A. Tracy

Theses and Dissertations

The etiological connection between internalizing and externalizing disorders is poorly understood. This manuscript aims to investigate the roles of genes and then environment in the development of Major Depressive Disorder (MDD) and Antisocial Personality Disorder (ASPD) and the nature of their comorbidity in young adults. Data from a sample of 2,291 young adult male and female twins from the Young Adult Follow Up Study (YAFU) of the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) were used to estimate the proportion of variation in these traits that can be accounted for by additive genetic, shared environmental, and unique environmental factors. …


Genetic Dissection Of Behavioral And Neurogenomic Responses To Acute Ethanol, Aaron Wolen Dec 2001

Genetic Dissection Of Behavioral And Neurogenomic Responses To Acute Ethanol, Aaron Wolen

Theses and Dissertations

Individual differences in initial sensitivity to ethanol are strongly related to the heritable risk of alcoholism in humans. To elucidate key molecular networks that modulate ethanol sensitivity we performed a systems genetics analysis of ethanol-responsive gene expression in brain regions of the mesocorticolimbic reward circuit (prefrontal cortex, nucleus accumbens and ventral midbrain) across the BXD RI panel, a highly diverse family of isogenic mouse strains before and after treatment with ethanol. Acute ethanol altered the expression of ~2,750 genes in one or more regions and 400 transcripts were jointly modulated in all three. Ethanol-responsive gene networks were extracted with a …