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The Tumor Suppressor Pkcδ Is Critical For Uv-Induced G2/M Checkpoint Activation And Apoptosis, Edward Lewis Lagory

Dissertations

Protein kinase C delta (PKCδ) is an essential component of the intrinsic apoptotic program. Following DNA damage, such as exposure to UV radiation, PKCδ is cleaved in a caspase-dependent manner, generating a constitutively active catalytic fragment (PKCδ-cat) which is necessary and sufficient for keratinocyte (KC) apoptosis. We found that in addition to inducing apoptosis, expression of PKCδ-cat caused a pronounced G2/M cell cycle arrest in both primary human KCs and immortalized HaCaT cells. Consistent with a G2/M arrest, PKCδ-cat induced phosphorylation of Cdk1 (Tyr15), a critical event in the G2/M checkpoint. Treatment with the ATM/ATR inhibitor caffeine was unable to …

Gabab Regulation Of Methamphetamine-Induced Associative Learning, Robin Michelle Voigt

Dissertations

Addiction is a chronic, relapsing disorder for which strikingly few effective therapies exist, and there are no FDA-approved pharmacotherapies for methamphetamine (Meth) addition. There is an immense need to identify the neurobiological underpinnings of psychostimulant addiction and develop efficacious drug therapies to compliment the current mainstay treatment of behavioral/cognitive therapy.

Re-exposure to cues associated with psychostimulants (e.g., drug paraphernalia) increase neuronal activity and can elicit drug-craving and -seeking; an effect which is profound and long-lasting. A mechanism to disrupt those brain processes which are necessary to maintain the association may reduce the incidence of cue-elicited relapse.

Conditioned place preference (CPP) …

Deconstructing Ihf-Mediated Inhibition Of The Complex Acs Promoter, David S. Thach

Dissertations

acs encodes a high affinity enzyme that permits survival during carbon starvation. As befits a survival gene, its transcription is subject to complex regulation. Previously, the Wolfe lab reported that CRP activates acs transcription by binding tandem DNA sites located upstream of the major acsP2 promoter and that the nucleoid protein IHF binds three specific sites located just upstream. The most proximal site (IHF III) exhibits reduced transcription compared to the full-length promoter or to a construct lacking all three IHF sites. The goal of my research was to understand how IHF III inhibits CRP-dependent acs transcription. First, I helped …

Developmental Characterization Of Cara Mitad: A Drosophila Nuclear Receptor Co-Regulator, Chhavi Chauhan

Dissertations

In insects and vertebrates, hormone titers drive cellular proliferation and differentiation events that guide proper development. Nuclear receptors (NR) respond to these hormone signals by activating cascades of gene expression, along with coregulator protein complexes. In Drosophila melanogaster, fluctuating titers of the steroid hormone ecdysone are responsible for coordinating the timing of organismal development. Despite major advances in our understanding of Drosophila NR activities, we lack essential knowledge of the coregulators that are required for their proper function.

We have recently identified the Drosophila cara mitad (cmi) (`dear half') gene. The deduced CMI protein is closely related to the N-terminal …

Polyomavirus Enhancer Activator 3 (Pea3), A Member Of The Ets Family Of Transcription Factors, Is A Transcriptional Activator Of Notch-1 And Notch-4 In Breast Cancer: An Opportunity For Novel Combinational Therapy, Anthony George Clementz

Dissertations

Women diagnosed with triple-negative breast cancer have the worst overall prognosis and frequently present with metastatic tumors. To date, there are no targeted therapies available to combat this aggressive form of breast cancer due to the lack of expression of well-known targets such as ER-alpha, PR, or HER2/neu. Therefore, there is an immediate need to identify novel targets that are responsible for the proliferation, survival, and invasive phenotype. Notch-1 and Notch-4, both potent breast oncogenes, are overexpressed in triple-negative breast cancers-associated with the poorest overall survival. PEA3 (polyomavirus enhancer activator 3), a member of the Ets family of transcription factors, …

The Role Of Igf-1 And Notch Signaling In Thoracic Malignancies., Sandra Eliasz

Dissertations

Thoracic malignancies are one of the deadliest of all cancers, being the leading cause of cancer death in the Western world. Thoracic malignancies arise from different tissues; however the most common are of epithelial (commonly referred to as non-small cell lung cancer, or NSCLC), neuroendocrine (small cell lung cancer, or SCLC) and mesothelial origin (malignant mesothelioma, or MM). The DNA oncogenic virus Simian Virus 40 (SV40) has been shown to cooperate with environmental oncogenic fibers in the onset of MM. Insulin like growth factor-1 (IGF-1) signaling plays a central role in all thoracic malignancies and in the process of SV40-mediated …

Notch Signaling Is Important In The Survival, Proliferation, And Self-Renewal Of The Putative Breast Cancer Stem Cell Population, Peter Grudzien

Dissertations

Numerous studies have identified stem-like cells, termed cancer stem cells (CSCs), in breast tumors and established cell lines. It has been hypothesized that CSCs are responsible for breast cancer formation, progression and recurrence; therefore, a deeper understanding of the signaling pathways regulating CSC survival will benefit development of novel therapeutic strategies. Notch signaling, which is dysregulated in breast cancer and has been implicated in mammary stem cell self-renewal, and can be effectively blocked by gamma-secretase inhibitors (GSIs). While GSIs are currently in clinical trials for breast cancer, it is not fully understood how these compounds will affect CSCs or if …

New Cyclophanes As Supramolecular Scaffolds: The Synthesis Of Tribenzo-1,4,7-Triazacyclononatriene., Andria M. Panagopoulos

Dissertations

Supramolecular chemistry involves the formation of complex molecular entities that have the capacity to participate in specific molecular recognition of guest molecules. A commonly employed scaffold in supramolecular chemistry is the trimeric crown-shaped molecule cyclotriveratrylene (CTV). CTV has been studied extensively for its capability of binding a number of smaller organic and organometallic guests within its bowl-shaped cleft and has been used as a building block enabling the construction of more complex cryptophanes. The goal of this research is the synthesis and characterization of a novel cyclophane, tribenzo-1,4,7-triazacyclononene and derivatives thereof. These new cyclophanes should have greater versatility than the …

Lysine Specific Demethylase-1 And The Brahma Chromatin Remodeling Complex Regulate Conserved Signaling Pathways During Drosophila Wing Development, Brenda Jean Curtis

Dissertations

The conserved SWI/SNF chromatin remodeling complex uses the energy from ATP hydrolysis to alter local chromatin environments by disrupting DNA-histone contacts. The Drosophila SWI/SNF counterpart, the Brahma complex, has been shown to have an essential role in regulating the proper expression of many developmentally important genes, including those required for eye and wing tissue morphogenesis. A temperature sensitive mutation in one of the core subunits, SNR1 (SNF5/Ini1/SMARC B1), results in reproducible wing patterning phenotypes that can be enhanced and suppressed by extragenic mutations. SNR1 functions as a regulatory subunit to modulate chromatin remodeling activities of the Brahma complex on target …

Aging Effects On Acute Lung Inflammation After Burn Injury, Vanessa Nomellini

Dissertations

The risk of complications and death after a moderate sized burn injury is significantly higher in persons over the age of 65, while almost non-existant in young, healthy individuals. The studies outlined below use a murine model to determine the mechanisms behind the development of pulmonary complications that frequently occur in aged individuals following burn injury. We hypothesized that, since aged mice maintain an elevated proinflammatory state prior to injury, they are at an even greater risk of pulmonary inflammation than young mice given a comparable sized wound. We found that neutrophils continue to accumulate in the lungs of aged …

Involvement Of The Nmda Receptor In Moderate Ethanol Preconditioning-Dependent Neuroprotection From Amyloid-Beta In Vitro, Robert Matthew Mitchell

Dissertations

Alzheimer's disease (AD) is a progressive, mentally crippling, and eventually fatal form of dementia with growing prevalence in aging populations. In 2009 it was estimated that 5.3 million Americans have AD, with 5.1 million older than age 65 and 200,000 under 65. That accounts for 1 in 8 adults over 65. Furthermore, AD costs Americans 148 billion dollars in direct expenses, and is the leading cause of dementia and the 6th leading cause of death. Since improved medical care in general is increasing average life span and age is the primary risk factor for AD, there is need for basic …

Ethanol Impairs Mechanisms Of Macrophage Phagocytosis And Cytokine Production, John Karavitis

Dissertations

Extensive evidence indicates that alcohol (ethanol) consumption affects human health by altering normal physiological functions of the immune system. This study investigated the effect of a single in vivo exposure of macrophages to clinically relevant levels of ethanol (1.2 and 2.2 g/kg). Following 3 hour exposure, both doses of ethanol decreased ex vivo TNFα production by splenic and alveolar macrophages (AMs). Interestingly, the higher dose of ethanol resulted in sustained suppression of LPS-induced TNFα production at 3 and 6 hours post ethanol administration, as well as decreased IL-6 and IL-12 production after 6 hours, compared control treated groups. LPS or …

Hypervirulent Clostridium Difficile Strains: Adherence, Toxin Production And Sporulation, Michelle Marie Merrigan

Dissertations

Clostridium difficile is a leading cause of nosocomial infections, and recently emerged "hypervirulent" C. difficile strains have caused epidemics worldwide. We hypothesized that multiple factors were responsible for this phenotype, particularly the interaction of C. difficile with the epithelial cell, as well as toxin production and sporulation.

To test if host interaction varied in HV strains, we developed a quantitative host-cell adherence assay, and found that while C. difficile strains varied in adherence to human intestinal epithelial cells, hypervirulent strains were not significantly more adherent than other strains. The bacterial surface protein SlpA varied in both size and amount between …

Hindbrain Serotonin Neurons Activate 5-Ht1a Receptors In The Nucleus Tractus Solitarius (Nts) To Modulate Sympathetic And Ventilatory Recovery Following Hypotensive Hemorrhage, Ling-Hsuan Kung

Dissertations

Trauma is the leading cause of death of young people in the United States. Most such deaths result either from the initial blood loss or from secondary reperfusion injury following resuscitation.

Currently, the standard treatments for hypovolemic shock include volume resuscitation and using of vasoconstrictors to raise pressure. However, these treatments can exacerbate reperfusion injury, and require technical care when apply to patients. Therefore, novel therapies that can safely restore perfusion pressure are needed.

Our lab has found that 5-HT1A-receptor agonist, 8-OH-DPAT, increases perfusion pressure and improves acid-base balance in hypovolemic rats by stimulation of sympathetic-mediated increases in venous tone. …

Forced-Exercise Alleviates Neuropathic Pain In Experimental Diabetes: Effects On Voltage-Gated Calcium Channels, Sahadev A. Shankarappa

Dissertations

Exercise is now established as an integral adjunct to the management of diabetes. Diabetic polyneuropathy, a painful complication of diabetes, remains untreatable, emphasizing a critical need for improved therapeutic strategies. Recent evidence suggests that exercise may facilitate recovery of peripheral nerve function in diabetes. However, the mechanism by which exercise protects against diabetes-induced nerve dysfunction is unknown. In this dissertation we hypothesized that forced-exercise protects against experimental DPN by preventing glucose-associated alterations of voltage-gated calcium currents (VGCC) in small diameter dorsal root ganglion (DRG) neurons. Using behavioral, nerve-electrophysiology and patch-clamp methodology we examined the functional consequences of forced-exercise (treadmill, 5.4 …

Camkii-Mediated Phosphorylation Of The Inositol 1,4,5-Trisphosphate Receptor At Serine-150 Results In Decreased Channel Activity, Joshua Thomas Maxwell

Dissertations

One mechanism by which calcium is mobilized from intracellular stores is via the activation of inositol 1,4,5-trisphosphate receptors (InsP3Rs) by the second messenger, inositol 1,4,5-trisphosphate (InsP3). InsP3 is produced when certain factors bind to G protein-coupled receptors on the plasma membrane, causing activation of phospholipase C which cleaves InsP3 from its membrane tether, allowing InsP3 to diffuse through the cytoplasm to bind to its receptor. Activation of InsP3Rs leads to release of calcium into the cytoplasm of the cell, where it can activate a multitude of signal transduction cascades and a variety of local and global cellular events. One such …

Coronavirus Replicase Proteins: Multifunctional Mediators Of Replication And Innate Immunity Evasion, Mark Anthony Clementz

Dissertations

Coronaviruses are positive-sense, single-stranded RNA viruses. The majority of the RNA encodes non-structural proteins (nsps) that are translated as a large polyprotein, which is cleaved by the papain-like (PLP) and picornavirus 3C-like (3CLpro) proteases. The nsps modify host membranes to produce double membrane vesicles (DMVs) upon which the replicase-transcriptase assembles and synthesizes viral RNA. nsp3, nsp4, and nsp6 are integral membrane proteins believed to be involved in DMV formation. Work presented here demonstrates that nsp4 is subjected to N-linked glycosylation and mutation of N258 to threonine in nsp4 confers a temperature sensitive phenotype to MHV-A59 infectious clone virus. This virus …

Fish Assemblage Structure In Natural, Channelized, And Restored Sections Of Nippersink Creek, Mchenry County, Illinois, Sarah Ann Zack

Master's Theses

Degradation of aquatic habitats and loss of biodiversity are growing concerns of natural resource managers and the general public. Channelization, the common historical practice of straightening streams and rivers for agricultural interests, has had profound detrimental effects on the biodiversity of lotic fish assemblages. Nippersink Creek, McHenry County, IL is a twenty-three mile stream that flows through an area valued for its fish, wildlife, and invertebrate biodiversity. Although a portion of the stream was channelized in the 1950's, restoration efforts by the McHenry County Conservation District have recently restored historical meanders. Nevertheless, efforts to restore streams and rivers to their …

Temporal Variability Of Bioassessment Indices Used To Evaluate Three Midwestern Streams, Nia M. Haller

Master's Theses

Population, community and functional measures or metrics in rapid bioassessment programs aid in establishing biological criteria for streams and rivers. Each metric measures different aspects of community structure and is important in detecting changes in macroinvertebrate community structure that are influenced by changes in water quality. In this study, temporal variation of nine commonly used bioassessment indices was examined in three midwestern streams. The indices were calculated for each of nine replicate benthic macroinvertebrate samples collected monthly for one year from Cowpie Creek (CC), Nippersink Creek (NC) and Lawrence Creek (LC), McHenry County, Illinois. In practice, the habitat sampled for …

Diet Overlap And Competition Among Native And Non-Native Small-Bodied Fishes In The Colorado River, Grand Canyon, Arizona, Sarah Ellen Zahn Seegert

Master's Theses

Introductions of non-native fishes are threatening native fish communities in streams and rivers across the United States. The Colorado River especially has experienced numerous species invasions, and native fish populations throughout the basin are in decline. The native fish community in the Grand Canyon has been particularly affected, with half of the native fishes extirpated from the canyon. Many scientists blame interactions with non-native fishes for these declines. However, to date no one has conducted a thorough diet analysis of small-bodied fishes in the system to assess overlap between native and non-native fish diets. I analyzed the diets of native …

Resource Composition And Macroinvertebrate Resource Consumption In The Colorado River Below Glen Canyon Dam, Holly Ann Alfreda Wellard Kelly

Master's Theses

Physical and biological changes to rivers induced by large dams can significantly alter downstream communities, decreasing the biotic integrity of these rivers. For example, completion of Glen Canyon Dam on the Colorado River in 1963 has altered the downstream ecosystem and contributed to the decline of native fish populations and dramatic changes in the macroinvertebrate communities. Physical changes associated with the dam may also influence the food resources supporting macroinvertebrate production, but this has not been previously measured. For example, autochthonous production is high in the clear tailwaters of the dam, but downstream tributary allochthonous carbon inputs are substantial and …

Structure-Function Relationship Studies Of The Udp-Glucose Pyrophosphorylase From Escherichia Coli, Agnieszka Maria Orlof

Master's Theses

UDP-Glucose Pyrophosphorylase (UDP-Glc PPase) is a key enzyme of the carbohydrate metabolic pathway widely used among prokaryotes and eukaryotes. In plants, UDP-Glc PPase is necessary for sucrose synthesis while mammals utilize this enzyme for the production of glycogen. A bacterium such as Escherichia coli uses UDP-Glc PPase for biosynthesis of the lipopolysscharide core which forms a cell wall.

This study focused on UDP-Glc PPase from Escherichia coli which is encoded by both galU and galF genes. The first part of this project investigated amino acids that could play an important role in the function of UDP Glc PPase (GalU). Based …

Functional And Phenotypical Analysis Of The Effects Of Aging On B Cells And Their Bone Marrow Microenvironment, Nicole May Ziegler

Master's Theses

Aging impacts multiple organ systems, and specifically causes the immune system to lose its ability to efficiently fight off infections. Regarding immunity, aging research predominantly focuses on the adaptive immune system. B cells, which mediate the humoral arm of the adaptive immune system, develop throughout life in the bone marrow where microenvironmental `niches' are important. The bone marrow does not exactly `atrophy' with age; however, studies comparing young and old mice demonstrate an age-related change in the bone marrow B cell subpopulations.

The overall goal was to determine if femoral and sternum bone marrow have different plasma cell composition and …

The Distribution Of Gnrh And Erbeta In Pre- And Post-Pubertal Male Rats, Maysaa Nageeb

Master's Theses

The hypothalamic-pituitary- gonadal axis is intrinsic in regulating reproductive function. Each part orchestrates the synthesis and release of a key hormone. At the level of the hypothalamus, Gonadotropin- releasing hormone (GnRH) is released and it is the

most upstream regulator of sexual maturation. GnRH neurons express a type of estrogen receptor, ERbeta, which suggests that estradiol (E2) plays a direct role in modulating GnRH function (Herbison and Pape 2001). The objective of this study was to determine if gonadal steroid hormones regulate the expression of ERbeta and GnRH mRNA in the male brain during pubertal development. In-situ hybridization was used …

Mechanisms Of Ipsapirone-Mediated Neuroprotection Of Ethanol-Treated Fetal Rhombencephalic Neurons: Role Of Endogenous Antioxidants, Jongho Lee

Dissertations

Prenatal exposure to ethanol can cause serious damage to the developing central nervous system. Both in vivo and in vitro studies demonstrate the vulnerability of the developing serotonergic system to the damaging effects of ethanol. However, treatment with a serotonin-1A (5-HT1A) agonist prevents the ethanol-associated apoptosis in developing 5-HT neurons. One mechanism by which 5-HT1A agonists exert their neuroprotective effects appears to involve activation of the phosphatidylinositol 3'kinase (PI-3K) pro-survival pathway and activation of NF-κB dependent anti-apoptotic genes. Additional NF-κB dependent genes might also be involved with the neuroprotective effects of ipsapirone.

There is also considerable evidence that ethanol augments …

Phenotypical And Functional Analysis Of Peripheral T Cells In Foxn1 Transgenic Mice: Effects Of Aging, Paulette Krishack

Master's Theses

The thymus is the primary organ for the development and production of TCRαβ naive T cells. However, with increasing age thymic involution occurs, causing a decline in the output of naïve T cells. The decline in naïve T cell production results in a contraction in the peripheral naïve and expansion of the memory T cell pools. Not only are the production and compositions of peripheral T cells altered with age, T cell functions such as T cell proliferation and production of cytokines required for cell proliferation are also declined. Currently, it is not known if restoring the decline in the …

Localization And Functional Analysis Of Plasmodium Falciparum Genes Pfl2550w And Pff0750w, Carolyn Jane Strobel

Master's Theses

Malaria is a parasitic disease that causes over a million deaths worldwide each year. Understanding development through the parasite's life cycle is necessary to stop disease transmission. As the genetic basis for the crucial transition from the erythrocytic asexual cycle to gametocytogenesis is unknown, we hope to better understand this transition by studying sexual stage genes and their roles in gametocytogenesis. PFL2550w and PFF0750w are genes upregulated during gametocytogenesis that were identified by a whole-genome microarray comparing gene expression between gametocyte-producing and gametocyte-deficient strains. In this study, PFL2550w was shown to be a soluble protein that is exported from the …

Phospholipase D Signaling In T Cells, Uma Chandrasekaran

Dissertations

Antigen stimulation of T lymphocytes induces the activation of phospholipase D (PLD) signaling. Phospholipase D (PLD) is a phosphodiesterase that catalyzes the conversion of phosphatidyl choline (PC) to phosphatidic acid (PA). PA is an important lipid second messenger and is known to mediate a variety of cellular functions. However, the specific role of PA in T lymphocytes has not been established. Previous studies indicated differential requirement for TCR induced PLD signaling in regulatory and non-regulatory T cells. Inhibition of TCR induced PLD signal preferentially suppressed the growth of non-regulatory T cells while allowing the proliferation of regulatory T cells in …

B Lymphocyte Development In Galt, Venkata Arunachalam Yeramilli

Dissertations

In rabbits, the primary antibody repertoire is generated in the gut-associated lymphoid tissues (GALT), where bone marrow (BM)-derived B cells undergo a proliferative expansion and somatically diversify the immunoglobulin genes. Unlike in other species, B lymphopoiesis in rabbit arrests a few months after birth, and it is unclear how the peripheral B cell compartment is maintained when there is no influx of newly-made B cells from the BM.

For my dissertation, I investigated how B cells develop in the GALT of rabbits, and how they are maintained in adults after the arrest of lymphopoiesis. To identify cellular signals that promote …

Characterization Of Tram, A Required Bacteroides Fragilis Conjugal Apparatus Protein That Interacts With The B. Fragilis Putative Coupling Protein Bcta And The B. Fragilis Relaxase Protein Bmph, Mai Thi Thanh Nguyen

Dissertations

Bacteroides spp. organisms, the most prominent bacteria of the human colon, are reservoirs of antibiotic resistance genes which promiscuously transfer within and from the genus via conjugation. The B. fragilis clinical isolate LV23 harbors a 37kb conjugative transposon, BTF-37. Two important conjugal apparatus proteins encoded by BTF-37 are BctA, a predicted coupling protein (CP) that powers DNA translocation, and ORF7 (TraM). In this study, we demonstrated that TraM exhibits characteristics of a required conjugal apparatus protein including 1) upregulated expression under conjugation conditions; 2) localization to the bacterial inner membrane; 3) interaction with the putative coupling protein BctA and the …