Diseases Commons^™

Targeting The Colchicine Binding Site On Tubulin To Overcome Multidrug Resistance And Anticancer Efficacy Of Selective Survivin Inhibitors, Kinsle E. Arnst

Theses and Dissertations (ETD)

Tubulin inhibitors are widely used as chemotherapeutic agents, and their successis attributed to their ability to target microtubule dynamics and disrupt critical cellular functions including cell signaling, motility, intracellular trafficking, and mitosis. Interference with microtubule dynamics consequently disrupts mitotic progression and ultimately leads to apoptosis, validating microtubule dynamics as an excellent target for anticancer agents. While this class of drug has proven to be effective against many cancer types, the clinical efficacy of current tubulin inhibitors is often limited by the development of multidrug resistance. The most common form of resistance to these agents arises from the overexpression of drug …

Role Of Smarce1 And Bhlhe40 In Breast Cancer Metastasis, Aarti Sethuraman

Theses and Dissertations (ETD)

No abstract provided.

Novel Determinants That Influence Azole Susceptibility In Candida Glabrata And Candida Albicans, Sarah Garland Whaley

Theses and Dissertations (ETD)

Despite the scientific and medical communities’ best efforts, the incidence of fungal infections in susceptible populations continues to rise. The most common cause of these opportunistic fungal infections is Candida. In fact, Candida is the fourth most common pathogen associated with nosocomial blood stream infections. Reported mortality rates for patients with candidemia vary, but have not decreased in the past fifteen years and are reported to be as high as 50%. Candida glabrata, second only to Candida albicans among Candida infections, expresses high rates of resistance to treatment with arguably the best class of currently available antifungals - …

Pitx3null Mutant (Striatal Dopamine-Deficient) Mice Have Exaggerated Spiny Projection Neuron Responses To L-Dopa And D1 Agonism And Lack Baseline Striatonigral Spiking, Ben Sagot

Theses and Dissertations (ETD)

L-3,4 dihidroxyphenylalanine (l-DOPA) strongly stimulates motor activity in parkinsonian patients and animal models of Parkinson's disease. Severe striatal dopamine (DA) loss characterizes Parkinson's disease and its animal models. Given the canonical rate model of Parkinson's Disease pathophysiology based on differences in DA pharmacology manifesting as electrophysiological differences in striatal projection neuron (SPN) spike rates, SPNs should increase spiking during the motor response to l-DOPA. In fact, stimulating specific subsets of these neurons to spike in freely-moving wild type and parkinsonian animals causes or inhibits motor activity as predicted. However, pharmacological effects of DA deficiency, let alone those of DA replacement, …

Revealing A Non-Canonical Role Of Anti-Apoptotic Mcl-1 In Early Embryonic Development, Xue Yang

Theses and Dissertations (ETD)

MCL-1, a well-known pro-survival BCL-2 family member, is indispensable for the survival of various cellular lineages and is also among the most frequently amplified genes in a variety of human malignancies. Gene ablation studies previously revealed that Mcl-1 deficiency leads to embryonic lethality around E3.5 during peri-implantation stage. Strikingly, the study did not detect any increase in apoptotic cells of the blastocyst, indicating a function of MCL-1 beyond regulating apoptosis. Our previous studies revealed an unrecognized role of MCL-1 in promoting mitochondrial physiology, which is independent of its classical anti-apoptotic function and requires being imported into the mitochondrial matrix. In …

Metabolic Regulation Of Cellular Signaling, Rashid John Darbandi

Theses and Dissertations (ETD)

Using the biochemically tractable Xenopus oocyte model system, we have previously characterized a novel metabolic regulation of cell death. We found that glucose-6-phosphate (G6P) via the pentose phosphate pathway leads to increased nicotinamide adenine dinucleotide phosphate (NADPH) levels, a subsequent increase in cytosolic acetyl-coenzyme A and activation of Ca2+/calmodulin-dependent protein kinase II (CaMKII). We recently identified coenzyme A (CoA), derived from the breakdown of acetyl-CoA, as the key metabolic signal that mediates a novel mechanism of calmodulindependent activation of CaMKII. CoA binds directly to the calmodulin (CaM) binding domain (CaMBD) of CaMKII resulting in its activation and downstream inhibitory phosphorylation …

Discovery Of Novel Tubulin Inhibitors And Selective Survivin Inhibitors For Advanced Melanoma And Total Synthesis Of Bioactive 20s-Hydroxyvitamin D3, Qinghui Wang

Theses and Dissertations (ETD)

According to the statistics from American Cancer Society, the 5-year survival rate for patients with advanced melanoma is as low as 5%. Treatment of advanced melanoma, therefore, represents an unmet medical need. In this dissertation, I will show the effort to develop new generations of bioavailable tubulin inhibitors targeting the colchicine binding site and selective small-molecule survivin inhibitors for treating advanced melanoma. Extensive structure-activity relationship (SAR) studies of lead molecules ABI-231 and UC-112 have been performed.

Chapter 1 will introduce the current situation of advanced or metastatic melanoma, its clinical drug treatments, as well as problems in current drug treatments. …

Using S. Pombe To Study The Biological Roles Of The Histone Deacetylases Sir2 And Clr3 And The Dead-Box Rna Helicase Ded1, Brandon Ray Lowe

Theses and Dissertations (ETD)

The fission yeast Schizosaccharomyces pombe provides a good model system to quickly study basic mechanisms underlying biological pathways conserved in higher eukaryotes. Here we utilized fission yeast to study the roles of the histone deacetylases (HDACs) Sir2 and Clr3 in heterochromatin formation and cancer associated mutations of the DEAD-box RNA helicase DDX3X, homolog of fission yeast Ded1, in translational control. Heterochromatin in fission yeast is characterized by hypoacetylation as well as methylation of histone H3 on lysine 9 (H3K9me). Heterochromatin assembly can now be separated into three distinct steps: heterochromatin establishment, spreading, and maintenance. These steps involve the actions of …

Therapeutic Effects Of Ormeloxifene In Cervical Cancer Carcinogenesis, Neeraj Chauhan

Theses and Dissertations (ETD)

Cervical cancer (CxCa) remains the fourth leading cause of cancer related deaths among women worldwide. Cervical cancer is mainly (~ 99.7%) derived from high risk Human papillomavirus (HR HPV). HPV E6/E7 are the two main oncoproteins that interfere with p53 and pRb (retinoblastoma) cell cycle regulatory proteins and hinder their efficacy of controlling cell growth. Additionally, PI3K-Akt is a cell survival pathway that is aberrantly expressed in cervical cancer cells. This pathway has a profound role in inhibiting mitochondrial intrinsic apoptotic signaling pathway. Advanced stage cervical cancer is difficult to treat and patients diagnosed with metastatic disease have a poor …

Role Of Dendritic Cells In Pathology Of Respiratory Syncytial Virus Infection In Neonates, Bishwas Shrestha

Theses and Dissertations (ETD)

Respiratory syncytial virus (RSV) is one of the leading causes of bronchiolitis in children. We have shown that neonatal mice respond to primary RSV infection with T helper type 2 (Th2) biased immune responses, which are enhanced following reinfection. Dendritic cells (DCs) including myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) play important roles in driving host responses to RSV infection. mDCs present antigens to help Th cells differentiate, and pDCs protect against viral infection through type I interferons (IFNs). Despite data demonstrating importance of mDCs and pDCs in protection against RSV, it has not been studied in an age appropriate …

The Roles Of Nuclear Receptor Nr4a1 In Cancer Cell Proliferation And Skeletal Muscle Differentiation, Alexa Farmer

Theses and Dissertations (ETD)

Nuclear receptors (NRs) constitute a major class of drug targets in the treatment of various cancer types. NRs respond to cellular signals and become activated upon ligand binding to transcriptionally modulate expression of target genes. NR4A1 (Nur77) is a member of the NR4A family of nuclear receptors and displays an oncogenic profile in many cancer models. It is often upregulated in adult solid malignancies and is known to promote cell proliferation and survival. Knockdown studies of NR4A1 in cancer cell lines results in decreased cell growth and angiogenesis and increased apoptosis, suggesting NR4A1 is an oncogenic protein. Due to the …

Novel Oncogenic Drivers In Pediatric Gliomagenesis, Alexander K. Diaz

Theses and Dissertations (ETD)

Pediatric high-grade gliomas (pHGGs), with a two-year survival rate of less than 20%, are some of the most aggressive human cancers. This dissertation begins with our analysis of 127 pHGGs, including brainstem (BS) and non-brainstem (NBS) tumors, from 118 patients using next-generation sequencing technologies. Nearly one-third of BS-HGGs, also known as diffuse intrinsic pontine gliomas (DIPGs), harbored somatic heterozygous missense mutations in ACVR1, coding for a receptor serine-threonine kinase involved in bone morphogenetic protein (BMP) signaling. These alterations led to gain-of-function as evidenced by increased phosphorylation of downstream targets in primary astrocytes and zebrafish embryo ventralization. Whole-genome sequencing and …

The Role Of Drak2 In T Cell Function And Autoimmunity, Tarsha L. Harris

Theses and Dissertations (ETD)

The immune system utilizes many regulatory mechanisms to limit immune responses and ensure that immune cells target foreign pathogens and not healthy cells of the body. However, some immune cells can escape these checkpoints and attack the body’s healthy cells, leading to tissue destruction and devastating autoimmune disorders. For example, multiple sclerosis (MS) occurs when immune cells attack the myelin sheath surrounding neurons of the central nervous system (CNS). Likewise, the destruction of pancreatic islet cells by dysregulated immune cells leads to type 1 diabetes (T1D). Remarkably, there are more than 80 types of autoimmune diseases. An estimated 50 million …

Assessment Of The Zoonotic Potential Of A Novel Bovine Influenza Virus, Laura Evelyn Eckard

Theses and Dissertations (ETD)

A novel orthomyxovirus was recently identified from pigs, with subsequent work suggesting the natural reservoir being bovine populations. The virus had genome characteristics most similar to influenza C viruses (ICV) but, due to the extent of sequence divergence, was proposed as a new genus, influenza D virus (IDV). Current literature on IDV has largely focused on the agricultural significance of the virus and provided evidence for the agricultural impact via observation of widespread prevalence and pathology in laboratory infected cattle. However, only one study, which identified 1.3% seroprevalence in a small cohort, has addressed the zoonotic potential of IDV to …

Hit Identification For Pkcζ Inhibitors: Structure-Based Optimization, Virtual Screening, And Biological Evaluation, Xiaoxin Wu

Theses and Dissertations (ETD)

Protein kinase C ζ (PKCζ) is believed to be a promising target for the treatment of some diseases, including inflammatory diseases, obesity and diabetes. Hit identification of PKCζ inhibitors was conducted by structure-based modification, virtual screening and biological evaluation. Among all the compounds selected and synthesized, compound JW-1-60A showed moderate activity against PKCζ at 30 μM and 100 μM. The molecular modeling studies showed that the binding mode of JW-1-61A was very close to the binding mode of JP-3-149, a reported PKCζ inhibitor with very potent activity, which might partially explain the moderate activity of JW-1-61A. Based on the structure …

Antibodies To Heterogenous Nuclear Ribonucleoprotein A1 Penetrate Neurons Leading To Multiple Downstream Effects Resulting In Neurodegeneration, Joshua Nathan Douglas

Theses and Dissertations (ETD)

Multiple sclerosis (MS) is the most common demyelinating disorder of the central nervous system. MS is believed to occur in genetically susceptible individuals due to an unknown environmental stimulus. MS patients produce autoantibodies to heterogenous nuclear ribonuclearprotein A1 (hnRNP A1), an RNA binding protein (RBP) highly expressed in neurons. hnRNP A1 functions in pre-mRNA splicing, mRNA trafficking, and translation. Furthermore, the anti-hnRNP A1 antibodies are specific to a N-terminal region termed ‘M9’ which serves as a nuclear export sequence/nuclear localization sequence (NES/NLS) responsible for nuclear/cytoplasmic transport of the protein. In this manuscript we will provide data revealing that anti-hnRNP A1 …

Pten Signaling In Regulatory T Cells And Inflammatory Disease, Sharad Krishna Shrestha

Theses and Dissertations (ETD)

Regulatory T (Treg) cells suppress CD4+ T cell responses during homeostasis and inflammation to prevent autoimmunity and other immune disorders. Although the transcriptional and epigenetic programs impacting Treg cell function have been extensively studied, the signaling and metabolic pathways underlying Treg stability and function are not fully understood. In this study, we determined the role of the phosphatase PTEN in Treg cells. We found that specific depletion of PTEN in Treg cells results in excessive TH1 and T follicular helper cells (TFH) responses, associated with elevated germinal center (GC) B cells and spontaneous development of autoimmune and lymphoproliferative disease in …

Development And Evaluation Of Amphotericin B Loaded Iron Oxide Nanoparticles For Targeted Drug Delivery To Systemic Fungal Infections, Pavan Balabathula

Theses and Dissertations (ETD)

A targeted nanotheronostic drug delivery system to diagnose and treat life threatening invasive fungal infections (IFIs) such as cryptococcal meningitis was designed, developed, characterized, and evaluated. To address the development processes, first, iron oxide nanoparticles (IONP) (34-40 nm) coated with bovine serum albumin (BSA), loaded and targeted with amphotericin B (AMB) (AMB-IONP) was formulated by applying a layer by layer approach. Several designs (A, B, C, D, & E) of AMB-IONP were developed and their physicochemical properties such as drug loading with HPLC method, particle size, poly dispersity index (PDI), and ζ-potential using dynamic light scattering (DLS) technique, morphology with …

Genetic Control Of Survival And Weight Loss During Pneumonic Burkholderia Pseudomallei (Bp) Infection, Felicia D. Emery

Theses and Dissertations (ETD)

Burkholderia pseudomallei (Bp) is a saprophytic, gram-negative aerobe and the causative agent of the disease melioidosis. Melioidosis is an infectious disease that occurs in humans and animals and is prevalent in Southeast Asia, northern Australia and other tropical areas. Transmission occurs through direct contact with the organism via ingestion, inhalation, or through open wounds and skin abrasions. Clinical presentation is extremely variable and can range from acute septicemia with bacterial dissemination to distant sites, to an isolated pulmonary infection. Treatment of melioidosis can be problematic because it is often difficult to diagnose and Bp is resistant to a diverse group …

Development Of Oral Vaccines Against Lyme Disease, Rita Raquel Dos Anjos De Carvalho E Melo

Theses and Dissertations (ETD)

Lyme Disease, caused by the spirochete Borrelia burgdorferi, is the most common vector-borne disease in the United States and Europe. If left untreated, it can lead to permanent damage to the nervous and musculoskeletal systems. In some cases, patients that receive the recommended antibiotic therapy develop a debilitating health condition associated with substantial health care costs. Despite current preventive measures, the incidence and the geographic distribution of Lyme Disease continues to increase. Recent estimates from CDC suggest that the true number of cases of Lyme Disease in the US is approximately 300,000 per year. Yet, there is currently no vaccine …

Health-Related Quality Of Life In Children With Cancer, Tha'er Ghandi Almomani

Theses and Dissertations (ETD)

Health-related quality of life is an important phenomenon to measure in children undergoing treatment for cancer. However, the effects of different treatment modalities and cancer related factors over the duration of treatment have not been explored. To assess the effects of different child-, cancer-, and treatment-related factors, we analyzed a large sample of children undergoing curative treatment for 5 different childhood cancer diagnoses. These diagnostic groups were Hodgkin Lymphoma (HL), Acute Lymphoblastic Leukemia (ALL), Acute Myeloid Leukemia (AML), Osteosarcoma (OS), and Melanoma. We analyzed a sample of 710 patients across the five diagnostic groups over four time-points in treatment. These …

Adverse Effects Of Asparaginase In Pediatric Patients With Acute Lymphoblastic Leukemia, Chengcheng Liu

Theses and Dissertations (ETD)

Acute lymphoblastic leukemia (ALL) is the most common type of childhood cancer. Asparaginase is a critical treatment component for ALL. However, its use is complicated by adverse effects, such as hypersensitivity, osteonecrosis and pancreatitis.

Hypersensitivity to asparaginase typically requires discontinuation of current formulation and substitution with other formulations, but the differential diagnosis can be challenging, and the diagnostic utility of antibody tests is unclear. We comprehensively analyzed anti-Elspar (native E.coli asparaginase) IgG antibodies in 410 pediatric patients treated on an asparaginaseintensive front-line clinical trial. Of 169 patients (41.2%) who exhibited clinical allergy, 147 (87.0%) were positive for anti-Elspar antibody. Of …

Anal Cancer Risk Factor Management Practices And The Barriers And Facilitators Of Addressing Anal Health In The Hiv Primary Care Setting, Crystal Martin Walker

Theses and Dissertations (ETD)

Background: The incidence of anal cancer is only 1-2 per 100,000 people in the general population, but in people living with HIV and AIDS (PLWHA), the incidence is far greater by about 80 times. This is a striking disproportion, and it is vital for the healthcare provider and healthcare system to become more attentive to the risk of anal cancer in high-risk populations such as PLWHA. There are a number of modifiable risk factors for anal cancer in PLWHA such as smoking, non-adherence to antiretroviral therapy (ART), and risky sexual behaviors. The HIV primary care provider (HIV PCP) plays a …

The Role Of Occupational Therapy In The Prevention Of Infant Torticollis & Plagiocephaly, Anne H. Zachry

Faculty Presentations

AOTA includes health promotion as an Intervention approach in the Occupational Therapy Practice Framework: Domain and Process. As health care professionals, occupational therapy practitioners are responsible for promoting public health and wellness. Occupational therapists need to educate parents and caregivers about the importance of varying infant positions, providing tummy time, and limiting infant time spent in baby gear.

Hemoglobin A1c And The Diagnosis Of Diabetes And Prediabetes In Children And Adolescents, Jennifer Mcguire Hitt

Theses and Dissertations (ETD)

Although the American Diabetes Association (ADA) adopted the use of the glycated hemoglobin (A1C) test as a method of diabetes and prediabetes diagnosis, the ADA has not developed firm guidelines concerning the use of the A1C test in children and adolescents, as research has not validated thresholds in this group. Diabetes and prediabetes are diseases influenced by multiple factors, including race and ethnicity, age, vitamin D deficiency, and body mass index (BMI). The purpose of this study was to determine the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the A1C test compared to the gold …

Effect Of Nedd4 Haploinsufficiency On Insulin Sensitivity, Adiposity And Neuronal Behaviors, Jingjing Li

Theses and Dissertations (ETD)

The neural precursor cell expressed developmentally down-regulated gene 4 (NEDD4) is a HECT-type E3 ubiquitin ligase that has received broad attention in recent years. Many of its reported substrates are active players in metabolism, implying a potential role of NEDD4 itself in metabolic regulation. Since homozygous Nedd4 deletion leads to embryonic or perinatal lethality, we investigated the function of NEDD4 in metabolic regulation in vivo, using Nedd4- haploinsufficient mice in a high fat diet-induced obesity (HFDIO) model.

Our studies show that Nedd4-haploinsufficient mice fed a normal diet (ND) exhibited decreased body weight in both genders and proportionally reduced tissue mass …

An Examination Of Factors That Influence Health Behaviors Among Low Income African American Women With Type 2 Diabetes In Memphis, Tn: A Qualitative Inquiry Using Mixed Methods, Adole Muruako

Theses and Dissertations (ETD)

Obesity and type 2 diabetes are increasing health concerns in the United States, particularly among women and minorities. Generally, research has highlighted the health disparities that exist among African American women, especially as these disparities relate to obesity and type 2 diabetes. In Memphis, TN, the ZIP codes of 38106 and 38109 have the highest rates of diabetes hospitalizations in the city. Further, African American women in Memphis, TN have been identified as being most vulnerable to experiencing a potentially avoidable hospitalization due to chronic disease. The purpose of study was to identify factors that may impact African American overweight/obese …

Autoimmune Susceptibility Imposed By Public Tcrβ Chains, Yunqian Zhao

Theses and Dissertations (ETD)

The major histocompatibility complex (MHC) is the strongest genetic risk factor for autoimmunity. It acts together with a corresponding TCR repertoire, yet, considering the extent of the repertoire's diversity, how this imposes disease susceptibility on a population is not well understood. We address the hypothesis that shared or public TCR, those present in most individuals, modulate autoimmune risk. High resolution analyses of autoimmune encephalomyelitis-associated T-cell receptor β chain (TCRβ) showed preferential utilization of public TCR sequences, implicating them in pathogenesis. Disease-associated public TCRβ, when transgenically expressed in association with endogenously rearranged T-cell receptor α chain (TCRα), could further endow unprimed …

Group Iv Cytosolic Phospholipase A2Α Is Critical For The Development Of Angiotensin Ii-Induced Hypertension And Associated Pathogenesis, Nayaab Shehbaz Khan

Theses and Dissertations (ETD)

Angiotensin II (Ang II) activates cytosolic phospholipase A2α and releases arachidonic acid (AA) from tissue phospholipids. AA metabolites mediate or modulate one or more renocardiovascular effects of this peptide and have been implicated in hypertension. Since AA release is the rate limiting step in eicosanoid production, it is possible that cPLA2α might play a central role in the development of Ang II-induced hypertension. To test this hypothesis, we investigated the effect of Ang II infusion for 13 days by micro-osmotic pumps (700 ng/kg/min), on systolic blood pressure and associated pathophysiological changes in wild type (cPLA2α+/+) and cPLA2α-/- mice. Ang II …

The Role Of Mcl-1 In The Heart: Gateway From Life To Death, Xi Wang

Theses and Dissertations (ETD)

MCL-1 is an essential BCL-2 family member that promotes the survival of multiple cellular lineages, but its role in cardiac muscle has remained unclear. Here, we have demonstrated that cardiac-specific ablation of Mcl-1 results in a rapidly fatal, dilated cardiomyopathy preceded by loss of myofibrils and cardiac contractility, abnormal mitochondria ultrastructure, defective mitochondrial respiration, and impaired autophagy. Genetic ablation of both pro-apoptotic effectors (Bax and Bak) could largely rescue the lethality and impaired cardiac function induced by Mcl-1 deletion. However, Mcl-1-, Bax-, and Bak-deficient hearts still revealed mitochondrial ultrastructural abnormalities and displayed deficient mitochondrial respiration, and are hypersensitive to chronic …