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Association Tests Of The Opioid Receptor System And Alcohol-Related Traits, Ryan Bennett Dec 2009

Association Tests Of The Opioid Receptor System And Alcohol-Related Traits, Ryan Bennett

Theses and Dissertations

The opioid receptors and their endogenous ligands have long been implicated in a variety of traits including addiction, impulsive behaviors and substance dependence. Using phenotypic measurements collected from the IASPSAD, data from a latent class analysis and data from a SNP array and additional genotyping assays, association and regression tests were performed to determine the effects of common SNPs encoded in the genes of the opioid receptors and ligands on various traits relating to alcohol dependence. Although only one SNP can be reported as significant for substance dependence within alcoholics, there were a few results approaching significance that may offer …


Effects Of Cannabinoid Receptor Interacting Protein (Crip1a) On Cannabinoid Receptor (Cb1) Function, Tricia Smith Nov 2009

Effects Of Cannabinoid Receptor Interacting Protein (Crip1a) On Cannabinoid Receptor (Cb1) Function, Tricia Smith

Theses and Dissertations

EFFECTS OF CANNABINOID RECEPTOR INTERACTING PROTEIN (CRIP1a) ON CANNABINOID (CB1) RECEPTOR FUNCTION. By Tricia Hardt Smith, B.S., M.S. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University Virginia Commonwealth University, 2009. Major Director: Dana E. Selley, Ph.D., Department of Pharmacology and Toxicology This dissertation examines modulation of cannabinoid CB1 receptor function by Cannabinoid Receptor Interacting Protein (CRIP1a), a novel protein that binds the C-terminus of CB1 receptors. In Human embryonic kidney cells expressing human CB1 receptors (hCB1-HEK) and hCB1-HEK cells stably co-expressing CRIP1a (hCB1-HEK-CRIP1a), quantitative immunoblotting revealed a CRIP1a/CB1 …


Nonhomologous End-Joining: Tdp1-Mediated Processing, Atm-Mediated Signaling, Amy Hawkins Nov 2009

Nonhomologous End-Joining: Tdp1-Mediated Processing, Atm-Mediated Signaling, Amy Hawkins

Theses and Dissertations

This thesis investigates two separate features of nonhomologous end-joining (NHEJ) DNA repair: end processing, and DNA repair kinase signaling. DNA end processing was investigated in a mouse model of hereditary spinocerebellar ataxia with axonal neuropathy (SCAN1), a congenital neurodegenerative disease. SCAN1 is caused by a homozygous H493R mutation in the active site of tyrosyl-DNA phosphodiesterase (TDP1). To address how the H493R mutation elicits the specific pathologies of SCAN1 and to further elucidate the role of TDP1 in processing DNA end modifications, we generated a Tdp1 knockout mouse and characterized their behavior and specific repair deficiencies in extracts of embryonic fibroblasts …


Denitration In Colonic Smooth Muscle, Seemab Malick Nov 2009

Denitration In Colonic Smooth Muscle, Seemab Malick

Theses and Dissertations

Tyrosine nitration results in altered function of smooth muscle voltage-gated L-type calcium channel. We explored the possibility that smooth muscle contains denitrase activity to allow functional recovery of the calcium channel without requiring synthesis of new channel proteins. Following peroxynitrite treatment of mouse colonic smooth muscle strips, CaCl2 (1 mM)-induced smooth muscle contraction was significantly reduced by 67% (P ≤ 0.05), which reversed by approximately 86% upon periodic washing within 2 hr period (P ≤ 0.001). The effect of the c-Src kinase inhibitor, PP2, on muscle contraction was also restored after 2 hr post-peroxynitrite treatment consistent with the thesis that …


Age-Related Genetic And Epigenetic Chromosomal Changes: A Twin Study, Kimberly Jones Nov 2009

Age-Related Genetic And Epigenetic Chromosomal Changes: A Twin Study, Kimberly Jones

Theses and Dissertations

The primary aims of this study were to examine acquired genetic and epigenetic changes that occur in individuals with increasing age and to determine how these changes are influenced by genetic/environmental factors. Acquired genetic changes were assessed by determining the frequency and chromosomal contents of spontaneously occurring micronuclei in identical and fraternal twins. A total of 115 individuals (48 twin pairs and 19 singletons) were evaluated, ranging in age from 7 to 85 years. As expected, micronuclei frequencies, which are indicative of genomic damage, significantly increased with age (p<0.0001, r=0.446). The majority of micronuclei (32%) contained sex chromosomes and the frequency of sex chromosome-bearing micronuclei significantly increased with age (p<0.0001). The frequency of autosome-containing micronuclei was not significantly influenced by age or gender. However, some autosomes were seen more (chromosomes 4, 8, and 9) or less (chromosomes 17 and 22) frequently than expected by chance (p<0.05). An evaluation of the numerical contents of the sex chromosome-containing micronuclei and their corresponding binucleates showed that the majority of the binucleates had an abnormal chromosomal complement (either hypodiploid or hyperdiploid), with the subset of binucleates having a normal chromosomal complement decreasing with age for both the Y chromosome in males and the X chromosome in females. Model fitting, implemented in Mx, showed the variation in the frequency of micronuclei to be best explained by either additive genetic and unique environmental components, or common and unique environmental factors. Specific environmental exposures and health conditions that were shown to influence micronuclei frequencies, included: multivitamins, leafy green vegetables, fruit, vitamin E supplements, arthritis, heart disease, allergies, and alcohol. To assess acquired epigenetic changes, global methylation profiles of two identical twin pairs were compared and found to differ, indicating that individuals do develop alterations in their methylation profiles with age. Furthermore, the twin pair having a significant difference in their micronuclei frequencies and environmental exposures had more differences in their methylation pattern compared to the twin pair whose micronuclei frequencies and environmental factors did not differ. Overall, genetic and epigenetic changes were shown to occur with age and to be influenced by genetic and lifestyle factors.


Genes And Symptoms Of Schizophrenia: Modifiers, Networks, And Interactions In Complex Disease, Sarah Bergen Sep 2009

Genes And Symptoms Of Schizophrenia: Modifiers, Networks, And Interactions In Complex Disease, Sarah Bergen

Theses and Dissertations

Understanding the genetic foundations of schizophrenia and the resultant symptom manifestations is an important step as we work toward development of new prevention and treatment strategies. This work has sought better understanding of this disease through use of three subject cohorts and two studies using simulated data exploring features of complex disease. First, we probed the symptoms of schizophrenia in subjects of African and European ancestry drawn from the Genetic Association Information Network (GAIN) schizophrenia study and found significant differences between groups, particularly in affective symptoms. The genetic basis of symptom variation was then explored in a selection of candidate …


Inhibition Of The Calcium Plateau Following In Vitro Status Epilepticus Prevents The Development Of Spontaneous Recurrent Epileptiform Discharges, Nisha Nagarkatti Sep 2009

Inhibition Of The Calcium Plateau Following In Vitro Status Epilepticus Prevents The Development Of Spontaneous Recurrent Epileptiform Discharges, Nisha Nagarkatti

Theses and Dissertations

Status epilepticus (SE) is a major clinical emergency resulting in continuous seizure activity that can cause brain injury and many molecular and pathophysiologic changes leading to neuronal plasticity. The neuronal plasticity following SE-induced brain injury can initiate epileptogenesis and lead to the ultimate expression of acquired epilepsy (AE), characterized clinically by spontaneous, recurrent seizures. Epileptogenesis is the process wherein healthy brain tissue is transformed into hyperexcitable neuronal networks that produce AE. Understanding these alterations induced by brain injury is an important clinical challenge and can lend insight into possible new therapeutic targets to halt the development of AE. Currently there …


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 …


Behavioral And Molecular Analysis Of Individual Variation In Ethanol Drinking, Jennifer Wolstenholme Jul 2009

Behavioral And Molecular Analysis Of Individual Variation In Ethanol Drinking, Jennifer Wolstenholme

Theses and Dissertations

A majority of Americans regularly consume alcohol, but the risk factors leading to excessive drinking and alcohol abuse are unevenly distributed throughout the population. Genetic differences can account for only 40-60% of this variability. While variations in ethanol preference drinking in rodent models have been reported, the neurobiological factors underlying these behaviors are still not completely understood. Thus, these studies were designed to determine behavioral and molecular factors associated with the initiation of ethanol drinking preference in an inbred mouse model. We harnessed the power of inter-individual variation of ethanol drinking within an inbred mouse strain to essentially eliminate genetic …


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 …


Enzymatic Regulation Of Opioid Antinociception And Tolerance, Lynn Hull Jul 2009

Enzymatic Regulation Of Opioid Antinociception And Tolerance, Lynn Hull

Theses and Dissertations

ENZYMATIC REGULATION OF OPIOID ANTINOCICEPTION AND TOLERANCE By Lynn C. Hull, Ph.D. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2009 Director: William L. Dewey, Ph.D. Department of Pharmacology and Toxicology The involvement of kinases in opioid actions has long been established. The acute actions of opioids, through the Gi/Go G-proteins, cause the inhibition of adenylyl cyclase and therefore a decrease in protein kinase A (PKA) activation. Additionally, acute opioid administration may cause the G-protein to activate the phospholipase C (PLC)-mediated cascade leading to the …


Triptolide Is A Potential Therapeutic Agent For Alzheimer’S Disease, Matthew Allsbrook Jul 2009

Triptolide Is A Potential Therapeutic Agent For Alzheimer’S Disease, Matthew Allsbrook

Theses and Dissertations

Mounting evidence indicates an involvement of inflammation in the pathogenesis of Alzheimer’s disease. While there are other mechanisms involved, it is this role of inflammatory processes that we wish to investigate. Triptolide is the major constituent in the Chinese herb, Tripterygium wilfordii Hook F, and has been used for centuries as part of Chinese herbal medicine. The four ringed structure has close homology to drugs of the steroid class and it has been shown to be beneficial as an anti-inflammatory for rheumatoid arthritis and for treatment of certain cancers. The aim of this study was to evaluate the potential therapeutic …


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 …


Transcriptional, Epigenetic, And Signal Events In Antifolate Therapeutics, Alexandra Racanelli Jun 2009

Transcriptional, Epigenetic, And Signal Events In Antifolate Therapeutics, Alexandra Racanelli

Theses and Dissertations

A targeted approach to the development of antifolate therapies has been sought for many years. Central to the success of such development is an understanding of the molecular mechanisms dictating the sensitivity of cells to antifolates and the fundamental differences of these processes between normal and neoplastic phenotypes. This dissertation addressed transcriptional mechanisms and cell-signaling events responsible for the efficacy of antifolate therapies. Transcriptional processes and cell signaling pathways are often aberrant in neoplastic tissues, providing a potential point of distinction between a normal and neoplastic cellular state. Folylpolyglutamate synthetase (FPGS) catalyzes the formation of poly-γ-glutamate derivatives of folates and …


The Effect Of Chronic Constriction Injury On Cellular Systems Within Nociceptive Pathways In The Mouse, Michelle Hoot Jun 2009

The Effect Of Chronic Constriction Injury On Cellular Systems Within Nociceptive Pathways In The Mouse, Michelle Hoot

Theses and Dissertations

Chronic neuropathic pain is often difficult to treat due to its resistance to therapeutic intervention. This is due in part to the poor understanding of the physiological mechanisms involved in the establishment and maintenance of neuropathic pain states. The neuropathic pain model, chronic constriction injury of the sciatic nerve, produced robust pain hypersensitivity in our mice. It also induced significant changes in the mitogen activated protein kinase family, and the cannabinoid and µ-opioid systems in three different brain areas involved in the modulation or regulation of pain states. CCI induced a 2.5 fold increase in mRNA of the kinase Raf-1 …


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 …


Therapeutic Drugs In Cancer, Teneille Walker Apr 2009

Therapeutic Drugs In Cancer, Teneille Walker

Theses and Dissertations

The first study examined the interaction between low doses of the multi-kinase inhibitor sorafenib and the histone deacetylase inhibitor vorinostat in colon cancer cells. Sorafenib and vorinostat synergized to kill HCT116 and SW480 cells. In SW480 cells, sorafenib+vorinostat toxicity correlated with CD95 activation and CD95-stimulated autophagy. Drug lethality in SW480 cells was blocked by knock down of CD95. In SW620 cells that are patient matched to SW480 cells, sorafenib+vorinostat toxicity was significantly reduced that correlated with a lack of CD95 activation and lower expression of ceramide synthase 6 (LASS6). Overexpression of LASS6 in SW620 cells enhanced drug-induced CD95 activation and …


Therapeutic Drugs In Cancer And Resistance., Aditi Pandya Martin Apr 2009

Therapeutic Drugs In Cancer And Resistance., Aditi Pandya Martin

Theses and Dissertations

We investigated the mechanism of toxicity and resistance development of small molecule tyrosine kinase inhibitor lapatinib in HCT 116 colon cancer cells. Lapatinib mediated cell death in HCT 116 cells was caspase independent and involved cytosolic release of apoptosis inducing factor. Treatment of HCT 116 cells with 10µM Lapatinib lead to the outgrowth of lapatinib resistant HCT 116 cells. Our studies show that alterations in the expression and activation of Bcl-2 family proteins allow lapatinib resistant HCT 116 cells to resist cytotoxic effects of lapatinib as well as of other commonly used chemotherapeutic agents. In hepatoma and pancreatic cancer cells, …