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Anti-Cancer Effects Of Garcinol In Pancreatic Cancer Transgenic Mouse Model, Nadia Saadat

Wayne State University Dissertations

Adenocarcinoma of pancreas is recognized for its poor prognosis, as it progresses asymptomatically and is rarely diagnosed at early stage. According to American cancer society pancreatic cancer, it has lowest survival rate in all cancer types, with less than 6% five year survival rate. Surgical resection is only possible for 20% of diagnosed cases and current chemotherapy has only 15% response rate. Even the most favored drug, Gemcitabine, increases survival time only by a few months, depending on the stage at diagnosis. Some bioactive food components or nutraceuticals have shown chemopreventive and chemotherapeutic effects without added side effects. Garcinol is …

The Role Of Oxidative Stress In The Pathogenesis Of Epithelial Ovarian Cancer, Nicole Marie King

Wayne State University Dissertations

Ovarian cancer is the leading cause of death from gynecologic malignancies yet the underlying pathophysiology is not clearly established. The disease is usually diagnosed in the advanced stage and carries a poor prognosis. The 5-year survival rate is greater than 75% if diagnosis of the cancer occurs at an early stage; however, this rate drops to 20% when the tumor has spread beyond its origin. Thus, a method for early detection is critically needed, which can help prolong, or even save lives. Currently, an effective screening test for ovarian cancer is lacking. Many tests have been evaluated but have been …

Investigating Hfq-Mrna Interactions In Bacteria, Martha Audra Faner

Wayne State University Dissertations

Regulatory RNAs (sRNAs) are essential for bacteria to thrive in diverse environments and they also play a key role in virulence [11]. Trans-sRNAs affect the stability and/or translation of their target mRNAs through complementary base-pairing. The base-pairing interaction is not perfect and requires the action of an RNA binding protein, Hfq. Hfq facilitates these RNA-RNA interactions by stabilizing duplex formation, aiding in structural rearrangements, increasing the rate of structural opening, and/or by increasing the rate of annealing [18-21]. Hfq has two well characterized binding surfaces: the proximal surface, which binds AU rich stretches typical of sRNAs, and the distal surface, …

Characterization Of High-Voltage-Activated Calcium Channels In Retinal Bipolar Cells, Qi Lu

Wayne State University Dissertations

Retinal bipolar cells, conveying visual information from photoreceptors to ganglion cells, segregate visual information into multiple parallel pathways through their diversified cell types and physiological properties. Voltage-gated Ca²⁺ channels could be particularly important underlying the diversified physiological properties of different BCs. In this dissertation, I investigated the high-voltage-activated (HVA) calcium current in retinal bipolar cells in mice. In the first part of my dissertation, I characterized multiple bipolar cell-expressing GFP and/or Cre transgenic mouse lines. In the second part of my dissertation, by performing whole-cell patch-clamp recordings, I examined the electrophysiological properties of HVA calcium currents among CBCs and …

Mechanisms Of Cytokine-Induced Metabolic Dysfunction Of The Pancreatic Beta-Cell, Abiy Mussa Mohammed

Wayne State University Dissertations

MECHANISMS OF CYTOKINE-INDUCED METABOLIC DYSFUNCTION OF THE PANCREATIC BETA-CELL

by

ABIY MUSSA MOHAMMED

August 2013

Advisor: Dr. Anjaneyulu Kowluru

Major: Pharmaceutical Sciences

Degree: Doctor of Philosophy

Type I diabetes is characterized by an absolute insulin deficiency due to loss of pancreatic â-cell mass by autoimmune aggression. During the progression of the disease proinflammatory cytokines such as IL-1â, TNFá and INFã are secreted by infiltrated and activated T-cells and macrophages which ultimately damage the pancreatic â-cell. However, the signaling mechanisms involved in cytokine-induced damage are only partially understood. Phagocyte-like NADPH oxidase [NOX2] has been shown to play regulatory roles in the …

The Drosophila Interactions Database: Integrating The Interactome And Transcriptome, Thilakam Murali

Wayne State University Dissertations

In this thesis I describe the integration of heterogeneous interaction data for Drosophila into DroID, the Drosophilainteractions database, making it a one-stop public resource for interaction data. I have also made it possible to filter the interaction data using gene expression data to generate context-relevant networks making DroID a one-of-a kind resource for biologists. In the two years since the upgraded DroID has been available, several studies have used the heterogeneous interaction data in DroID to advance our understanding of Drosophila biology thus validating the need for such a resource for biologists. In addition to this, I have identified …

Thick Ascending Limb Nitric Oxide Production And Inhibition Of Nkcc2 Activity Are Impaired In Angiotensin Ii-Induced Hypertension, Vanesa Daniela Ramseyer

Wayne State University Dissertations

Cardiovascular disease is the leading cause of death in the US. Hypertension, which affects about 30 % of the US population, is an important risk factor in the development of this disease. Inappropriately elevated sodium reabsorption by the kidney contributes to hypertension; therefore, studying the mechanisms that lead to enhanced sodium transport is important in understanding this pathology. The thick ascending limb (THAL) reabsorbs 30% of the filtered sodium chloride load. Nitric oxide (NO) produced by NO synthase type 3 (NOS3) increases cyclic GMP (cGMP) and inhibits THAL transport by reducing Na/K/2Cl cotransporter type 2 (NKCC2) activity. Interestingly, in angiotensin …

Single-Molecule Studies Of Local And Global Nucleic-Acid Dynamics, Eric Muthuri Patrick

Wayne State University Dissertations

Nucleic acids undergo both global and local conformational changes that are important for their function. Structural studies have over the decades been invaluable in elucidation of various biomolecular mechanisms, hence contributing significantly to the understanding of biological events. However, a clear understanding of how molecules function in the cellular context requires investigation of their interconversion between multiple conformations, including mapping the folding landscape and any coupled changes in conformation. Work in this thesis focuses on fluorescence experiments, mainly at a single-molecule level to investigate such processes.

First, a novel single-molecule approach is described focusing on local dynamics within nucleic acids …

Overcoming Tumor Drug Resistance By Activating Amp-Activated Protein Kinase And Destabilizing Oncoproteins, Min Shen

Wayne State University Dissertations

Although considerable progress has been achieved in the field of cancer therapeutics, primary or acquired drug resistance remains a fundamental cause of therapeutic failure in cancer therapy. Among different mechanisms characterized that are responsible for tumor drug resistance, there is increasing evidence suggesting that dysregulation of gene expression, especially oncogene or tumor suppressor gene expression, at either gene transcription or protein synthesis level, can contribute to the drug-resistant phenotype. AMP-activated protein kinase (AMPK) is a well-known major cellular energy sensor, which negatively regulates metabolic pathways such as protein synthesis, fatty acid oxidation and glucose consumption. Activation of AMPK may suppress …

Impact Of Cryoablation On Tumor Immunity, Jesse Veenstra

Wayne State University Dissertations

Background and Objectives: Percutaneous cryoablation is a minimally invasive procedure for tumor debulking, which has the potential to initiate or amplify tumor immunity through the release of tumor-associated antigens and endogenous danger signals. However, enhanced immunity is rarely observed in treated patients, suggesting the need for mechanistic analysis. The goal is to determine how cryoablation affects tumor specific immunity and if the response can be improved through exogenous TLR9 stimulation.

Methodology: We evaluated anti-Her2/neu immunity following cryoablation in wt BALB/c and tolerant NeuT mice inoculated with neu or Her2 expressing mammary tumors TUBO and D2F2/E2 respectively. Mice were treated with …

Roles Of Neuregulin1 In Neuromuscular Junction Development, Jiajing Wang

Wayne State University Dissertations

Neuromuscular junction (NMJ) development is a multistep process mediated by coordinated interactions between nerve terminals, target muscles, and peri-synaptic glial cells, and thus requires reciprocal signals derived from every cell type. Neuregulin1s (NRG1s) are a family of predominantly neuronal growth and differentiation factors that are important for many aspects of nervous system development. In this thesis, both the effects of NRG1 on NMJ development and reciprocal effects of neurotrophic factors on NRG1 expression were studied as a means to define the complex regulatory communication at the NMJ. Using the chicken embryo as a model, methods were developed to study the …

Towards Personalized Medicine Using Systems Biology And Machine Learning, Calin Voichita

Wayne State University Dissertations

The rate of acquiring biological data has greatly surpassed our ability to interpret it. At the same time, we have started to understand that evolution of many diseases such as cancer, are the results of the interplay between the disease itself and the immune system of the host. It is now well accepted that cancer is not a single disease, but a “complex collection of distinct genetic diseases united by common hallmarks”. Understanding the differences between such disease subtypes is key not only in providing adequate treatments for known subtypes but also identifying new ones. These unforeseen disease subtypes are …

Mechanisms Mediating Modulation Of The Cardiopulmonary Chemoreflex Control Of Regional Sympathetic Outputs By Adenosine A1 And A2a Receptors In The Nts, Zeljka Minic

Wayne State University Dissertations

ABSTRACT

by

ZELJKA MINIC

August 2013

Advisor: Dr. Tadeusz J. Scislo

Major: Physiology

Degree: Doctor of Philosophy

Adenosine is an important neuromodulator of cardiovascular control at the level of the nucleus of the solitary tract (NTS) where cardiovascular and other autonomic reflexes are primarily integrated. Levels of adenosine increase in the NTS during life threatening hypotension, ischemia and hypoxia. Adenosine may modulate cardiovascular reflexes to correct hemodynamic imbalance, acting via A₁ and A_2a receptors which inhibit and facilitate neurotransmitter release, respectively. Previous studies from our laboratory showed that NTS A₁ adenosine receptors inhibit the arterial baroreflex whereas …

Platyrrhine Phylogenetics With A Focus On Callitrichine Life History Adaptations, Natalie Mae Jameson

Wayne State University Dissertations

The life history of a species is highly impacted by their reproductive strategy. In my dissertation I address the changing reproductive strategies in callitrichine New World monkeys and their genetic underpinnings using a phylogenetic approach. The necessity for a resolved phylogeny is universal to any comparative genomic study. Here we have constructed a reliable phylogenetic framework from which reproductive strategy could be studied in callitrichines. First, to determine the most recent common ancestor of Anthropoid primates we took a phylogenomic approach, using the publicly available whole genome sequences of 17 mammal species. With high confidence, we determined here that Tarsier …

Development Of Peptide Inhibitors Targeting Clostridium Difficile Toxins A/B And Characterizing The Regulatory Role Of A Putative Negative Regulator Tcdc In Clostridium Difficile Toxin Gene Expression, Sanofar Jainul Abdeen

Wayne State University Dissertations

Clostridium difficile infections cause one of the most common and vital hospitalacquired

diseases often associated with broad-spectrum antibiotic usage. TcdA and TcdB

are the key virulence factors involved in major patho-physiology. While standard

antibiotics provide some respite, due to the high relapse rates and the emergence of more

severe disease presentations, antibiotics alone have often proven to be suboptimal.

Therefore there is a desperate need to develop an effective non-antimicrobial

therapeutics. Part of this work focuses on identification and further characterization of

peptide therapeutic that target the major virulence factor TcdA/TcdB. Towards

development of mechanistic-based anti-toxin agent, phage display was …

Characterization Of Antimicrobial-Resistant Staphylococcus Spp. In Food Animals And Retail Meat, Kanika Bhargava

Wayne State University Dissertations

Antimicrobial resistance in Staphylococcus spp. is a worldwide epidemic concern in hospital and community settings. Food animals and retail meat are important reservoirs of these pathogens that can pose potential threat to humans. In this dissertation, we aimed to investigate the molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Coagulase-negative Staphylococci (MRCoNS) in food animals and retail meat to provide insight into the role of agricultural environment in transmitting bacteria of human clinical significance. Furthermore, the potential application of phytochemicals as antimicrobials and antimicrobial adjuvants to control MRSA infections was explored.

CoNS recovered from food animals were characterized by …

How Atomic Level Interactions Drive Membrane Fusion: Insights From Molecular Dynamics Simulations, Navendu Bhatnagar

Wayne State University Dissertations

This project is focused on identifying the role of key players in the membrane fusion process at the atomic level with the use of molecular dynamics simulations. Membrane fusion of apposed bilayers is one of the most fundamental and frequently occurring biological phenomena in living organisms. It is an essential step in several cellular processes such as neuronal exocytosis, sperm fusion with oocytes and intracellular fusion of organelles to name a few. Membrane fusion is a frequent process in a living organism but is still not fully understood at the atomic level in terms of the role of various factors …

Insight Into Human Brain Evolution Through Phylogenetic Analysis And Comparative Genomics, Amy Marie Boddy

Wayne State University Dissertations

As a species, humans are often considered to be unique among mammals, with respect to their large brain size and enhanced cognitive abilities. Humans are the most encephalized mammals, with a brain that is six times larger than expected relative to body mass. Presumably, it is this high degree of encephalization that underlies our advanced cognitive abilities, including the skills needed for complex language and culture. Understanding how large brains evolved can shed light on what makes the human brain unique and introduce possible mechanism for human specific neurodegenerative diseases. This study takes a both a phenotypic and molecular approach …

Functional Characterization Of The Cholera Toxin Promoter Of Vibrio Cholerae, Jennifer Dittmer

Wayne State University Dissertations

Vibrio cholerae is the bacterium responsible for the severe diarrheal disease cholera. The disease is directly caused by cholera toxin, which is secreted by the bacterium in the upper small intestinal lumen during the course of infection. Expression of cholera toxin, along with other virulence genes, is activated by the positive transcriptional regulator, ToxT. ToxT binds to DNA sequences known as toxboxes that are found within promoters of virulence genes and subsequently ToxT activates transcription. However, the toxboxes have not been previously characterized in arguably the most important virulence promoter in V. cholerae, the cholera toxin promoter (PctxAB). …

Expression And Regulation Of Map Kinase Phosphatases 1 And 2 In Breast Cancer Tamoxifen Sensitivity, Kelly Haagenson

Wayne State University Dissertations

ABSTRACT

EXPRESSION AND REGULATION OF MAP KINASE PHOSPHATASES 1 and 2 IN BREAST CANCER TAMOXIFEN SENSITIVITY

by

KELLY K. HAAGENSON

May 2013

Advisor: Dr. Malathy Shekhar

Co-Advisor: Dr. Gen Sheng Wu

Major: Cancer Biology

Degree: Doctor of Philosophy

The deregulation of cell signaling is a very important component in the development and progression of cancer. One group of signaling molecules that has been implicated in these processes is the Mitogen-Activated Protein Kinase (MAPK) family which consists of three major branches in mammalian cells: ERK, JNK and p38. The activity of these kinases has wide-ranging effects within the cell and must …

Investigation Of X Chromosome Recognition: The Role Of Small Rna In Drosophila Dosage Compensation, Debashish Unnikrishnan Menon

Wayne State University Dissertations

In humans and flies, females have two X chromosomes but males have one X chromosome and one Y chromosome. This leads to a fatal imbalance in X-linked gene expression in one sex. In mammals and in the fruit fly Drosophila, modulation of X chromosome expression is critical for survival. This process is termed dosage compensation. Flies increase expression from the male X chromosome two-fold. This is achieved by the Male Specific Lethal (MSL) complex, which consists of two large, non-coding RNA on the X transcripts (roX1 and roX2) and five proteins. The roX RNAs have a critical …

Fatty Acid Fate In Determining Oxidation And Inflammation In Adipose Tissue, Emilio Patrick Mottillo

Wayne State University Dissertations

Adipose tissue (AT) is a critical regulator of energy balance through its ability to store or oxidize free fatty acids (FFAs). White adipose tissue (WAT) functions as an anabolic organ to sequester and release FAs, in contrast brown adipose tissue (BAT) is a catabolic organ that oxidizes FAs. However, a comprehensive understanding of the role that FFAs play in the function of WAT and BAT is needed. Here we demonstrate that intracellular FAs enhance the expression of inflammatory cytokines by β3-AR activation in adipocytes, in which the expression of PAI-1 is partly mediated by the de novo synthesis of ceramides/sphingolipids. …

Elucidation Of The Functional Role Of Pcbp-The Cytosolic Iron Chaperone Protein Family, In Cellular Iron Homeostasis, Poorna Subramanian

Wayne State University Dissertations

Biological Role of Ferritin - Iron is essential for life and often utilized as a cofactor in many proteins. In humans, iron accumulation causes cirrhosis, arthritis, cardiomyopathy and diabetes mellitus, and it is associated with increased risk of cancer and heart disease. In contrast, decreased brain iron content results in permanent neurocognitive and motor impairment. Intracellular iron content must be maintained within a narrow range to avoid the adverse effects of iron depletion or excess, and this function is performed by the protein ferritin. Ferritins are iron storage proteins that are ubiquitously expressed in animals, plants and bacteria. They serve …

Development And Optimization Of The First High Throughput In Vitro Fret Assay To Characterize The Saccharomyces Cerevisiae Gpi-T, Sandamali Amarasingha Ekanayaka

Wayne State University Dissertations

DEVELOPMENT AND OPTIMIZATION OF AN IN VITRO FRET ASSAY TO CHARACTERIZE THE SACCHAROMYCES CEREVISIAE GPI TRANSAMIDASE

By

SANDAMALI AMARASINGHA EKANAYAKA

December 2013

Advisor: Dr. Tamara L. Hendrickson

Major: Biochemistry

Degree: Doctor of Philosophy

The enzyme glycosylphosphatidylinositol transamidase (GPI-T) mediates the attachment of a glycosylphosphatidylinositol (GPI) anchor to the C-terminus of specific proteins to produce GPI anchored proteins. This post-translational modification is essential for viability of eukaryotic organisms. However, very little is known about GPI-T and its catalytic activity. Thus, the research described in this abstract was conducted to develop an in vitro assay to monitor GPI-T. A high-throughput assay for …

Polymeric Nanocarriers And Their Oral Inhalation Formulations For The Regional Delivery Of Nucleic Acids To The Lungs, Denise Santos Conti

Wayne State University Dissertations

Gene therapy has attracted attention in the fields of medicine, pharmacy, and bionanotechnology due to the potential for treating a large number of medically relevant diseases. Oral inhalation (OI) is a promising route for the administration of therapeutics, including small molecules and biomacromolecules, such as nucleotides, peptides, and proteins, to (locally) and through (systemically) the lungs. The use of OI is especially attractive for the delivery of nucleic acids as it provides a direct and non-invasive route for targeting the lungs. Pressurized metered-dose inhalers (pMDIs), are the most commonly used OI in treatment of lung diseases and are thus promising …

Linking Environmental Toxicant Exposure To Diabetes Susceptibility, Jannifer Beth Tyrrell

Wayne State University Dissertations

An important and unresolved question in the environmental health field is whether exposure to common environmental toxicants, such as dioxin and heavy metals like Pb, increase the risk of developing diabetes, especially in combination with other common metabolic stressors such as obesity.

Previous studies suggested that dioxin exposure increased peripheral insulin resistance but did not appear to cause fasting hyperglycemia or elevated hepatic glucose output. In concordance with those findings we observed that dioxin treatment caused a strong suppression of the expression of the key hepatic gluconeogenic genes PEPCK and G6Pase. However, this suppression was not solely mediated by the …

Biochemical, Structural, And Drug Design Studies Of Multi-Drug Resistant Hiv-1 Therapeutic Targets, Tamaria Grace Dewdney

Wayne State University Dissertations

Protein point mutations acquired as a mechanism of survival against therapeutics cause structural changes that effect protein function and inhibitor binding. This work investigates the structural mechanisms that lead to multi-drug resistance to HIV-1 protease and integrase inhibitors.

Proper proteolytic processing of the HIV-1 Gag/Pol polyprotein is required for HIV infection and viral replication. This feature has made HIV-1 protease an attractive target for antiretroviral drug design for the treatment of HIV-1 infected patients, thus the development of drug resistance has arisen as a major therapeutic and drug design challenge. To understand the molecular mechanisms leading to drug resistance we …

Synthesis And Application Of Atp Analogs For Phosphorylation-Dependent Kinase-Substrate Crosslinking, Satish Kumar Garre Venkata Raghavendra

Wayne State University Dissertations

Phosphorylation is an important post-translational modification that plays a key role in a variety of signaling cascades and cellular functions. Kinases phosphorylate protein substrates in a highly regulated manner and are promiscuous. Understanding kinase-substrate specificity has been challenging and there is a need for new chemical tools. To this end we developed -phosphate modified ATP photocrosslinking analogs ATP-ArN3 and ATP-BP, that crosslink substrate and kinase in a phosphorylation dependent manner. We have successfully demonstrated that ATP-ArN3 and ATP-BP can be used with natural kinase and substrates using cell lysates in vitro. We used our approach to identify novel kinases of …

The Effect Of Proalgazyme And Its Subfractions On Lipid Metabolism In Diet Induced Hypercholesterolemic Hamsters: Correlation With Plasma Metabolomic Profile, Andreea Geamanu

Wayne State University Dissertations

ABSTRACT

THE EFFECT OF PROALGAZYME AND ITS SUBFRACTIONS ON LIPID METABOLISM IN DIET INDUCED HYPERCHOLESTEROLEMIC HAMSTRES:

CORREALTION WITH PLASMA METABOLOMIC PROFILE

by

ANDREEA GEAMANU

December 2013

Advisor: Dr. Smiti Gupta

Major: Nutrition and Food Science

Degree: Doctor of Philosophy

Background: Plasma HDL cholesterol levels are inversely related to cardiovascular disease, which is the leading cause of death worldwide. This study investigated the preventative effect of an algae infusion, ProAlgaZyme (PAZ) and its subfractions (F1, F2, F3, F4) on plasma HDL in a hamster model. Further, the study aimed to identify the biologically active fraction of PAZ and to determine the …

Single-Stranded Dna Scanning And Deamination With Single-Molecule Resolution, Padhuk Gamarala Senavirathne

Wayne State University Dissertations

SINGLE-STRANDED DNA SCANNING AND DEAMINATION WITH SINGLE-MOLECULE RESOLUTION

by

GAYAN SENAVIRATHNE

December 2013

Advisor: Dr. David Rueda & Dr.Ashok Bhagwat

Major: Chemistry (Analytical)

Degree: Doctor of Philosophy

APOBEC3G (Apo3G) and Activation-Induced cytidine Deaminase (AID) are the most notable members of APOBEC enzymes, a family of cytidine (C) deaminases with crucial functions in the immune system. In T cells, Apo3G deaminates C in viral cDNA to halt the replication of HIV 1 strains lacking viral infectivity factor (vif). In B cells, AID is required for the diversification of antibodies through initiation of somatic hypermutation (SHM), and class switch recombination (CSR), by …