Microbiology Commons^™

Microscopic Analysis Of Sympathetic And Parasympathetic Distribution, Terminal Morphology, And Interaction In Whole-Mount Atria, Scott Harden

Electronic Theses and Dissertations

The sympathetic (SNS) and parasympathetic (PSNS) branches of the autonomic nervous system (ANS) innervate the heart, exerting excitatory and inhibitory influences (respectively) over cardiac functions (heart rate, AV conduction velocity, and contractility). However, the distribution and structure of SNS and PSNS innervation has not yet been well studied. Detailed characterization of the distributional organization and structural morphology of the SNS and PSNS in normal states is essential to the study of pathological autonomic remodeling. The present study utilized double immunohistochemical labeling techniques to examine tyrosine hydroxylase (TH) immunoreactive (IR) SNS and vesicular acetylcholine transporter (VAChT) IR PSNS axons and terminal …

The Expression Of Mkrn1, An E3 Ubiquitin Ligase For Telomerase Reverse Transcriptase, Is Induced With Differentiation Therapy In Leukemia, Jose Salvatico

Electronic Theses and Dissertations

Telomeres are important structural and functional components of chromosomes, serving to provide stability and enabling full replication of the chromosomes. However, a shortening of the telomeres occurs with each cell division that can be fixed by a polymerase activity provided by telomerase, preventing this loss which would otherwise eventually lead to chromosome end-to-end fusions, senescence and cell death. The telomerase activity is present in stem cells and germ line cells, but absent or barely noticeable in adult somatic cells. However, in approximately 80-90% of transformed somatic cells the telomerase activity is recovered, resulting in a "telomerase positive phenotype". This phenotype …

High Resolution Single Molecule Optical Localization Of Multiple Fluorophores On Dna Origami Constructs Fluorophores On Dna Origami Constructs, Anuradha Rajulapati

Theses, Dissertations and Capstones

An ongoing challenge in the development of nanoelectronics and nanophotonics is the nondestructive, high-resolution localization in space of single molecules and multi-molecular assemblies. The apparent barrier to the use of optical microscopy at the sub-100 nm scale is the well known Abbe Limit, the diffraction limit to resolution. This laboratory has adapted a technique called Single-molecule high resolution imaging with photobleaching (SHRIMP). We have developed methods for utilizing SHRIMP for the determination of the separation of two fluorophores in single DNA origami constructs.

DNA Origami is extremely useful because it can address nanocomponents down to 2nm separation. It should be …

In Vitro Studies On Metabolism Of Salvinorin A, Lukasz M. Kutrzeba, Vardan T. Karamyan, Robert C. Speth, John S. Williamson, Jordan K. Zjawiony

Office for Research Publications and Presentations

Microbial transformation of natural products is a well established model for mammalian metabolism. Salvinorin A, a diterpenoid isolated from the hallucinogenic mint Salvia divinorum Epling & Játiva-M (Lamiaceae), is a potent non-nitrogenous κ-opioid receptor agonist. The metabolism of salvinorin A has still not yet been well established. Thirty fungal species were screened for the ability to metabolize salvinorin A. We observed that salvinorin A undergoes fast hydrolysis of the acetate group at carbon atom C2, resulting in formation of the pharmacologically inactive product, salvinorin B. Ex vivo experiments were also performed using organelle fractions isolated from rat liver and brain. …

Evaluation Of Glyphosate-Tolerant Soybean Cultivars For Resistance To Bacterial Pustule, Lopa Goradia, Glen Hartman, Steven L. Daniel

Faculty Research & Creative Activity

Xanthomonas axonopodis pv. glycines causes bacterial pustule of soybean, which is a common disease in many soybean-growing areas of the world and is controlled by a single recessive gene (rxp gene) commonly found in many conventional glyphosate-sensitive soybean cultivars. Since glyphosate-tolerant cultivars are commonly planted today, there has been no information about whether these new cultivars have bacterial pustule resistance. The goal of this study was to screen glyphosate-tolerant soybean cultivars for resistance to X. axonopodis pv. glycines. Three experiments were completed to evaluate resistance. In experiment 1, 525 commercial glyphosate-tolerant cultivars from 2001 were inoculated with X. axonopodis pv. …

Structure-Function Analysis Of Endoproteolytic Cleavage: Site-Directed Mutagenesis Studies Of The Α-Msh Cleavage Site In Silurana Tropicalis Pomc, Quinn Kun Chen

Electronic Theses and Dissertations

The maturation process of many prohormone molecules typically requires endoproteolytic cleavage C-terminal of dibasic residues, such as the K¹⁴¹R¹⁴²↓ site N-terminal of the α-melanocyte stimulating hormone (α-MSH) sequence in Silurana tropicalis proopiomelanocortin (POMC). In order to determine the absolute requirement of basic amino acid residues in the cleavage process, site-directed mutagenesis was employed to substitute alanine for the wild-type residues in the frog POMC open reading frame. Specifically, the following underlined residues were individually targeted for alanine substitution: R ¹³⁷ Q ¹³⁸ E ¹³⁹ N ¹⁴⁰ K ¹⁴¹ R ¹⁴²↓. The mouse pancreatic αTC1.9 cell …

Genetic Analysis Of Two Phenotypes In Variovorax Paradoxus Strain Eps, Michael Jherek Pehl

Theses Digitization Project

The formation of biofilms is a complex process that involves activation of a wide array of genetic material within the cells found living within the biofilm. It has been shown that altered colony morphology has been associated with different biofilm levels within P. aureginosa. This analysis will provide further evidence of the strength of the colony morphology screen to isolate mutants with altered biofilm or swarming abilities.

Evaluation Of Glyphosate-Tolerant Soybean Cultivars For Resistance To Bacterial Pustule, Lopa Goradia, Glen Hartman, Steven Daniel

Faculty Research & Creative Activity

Xanthomonas axonopodis pv. glycines causes bacterial pustule of soybean, which is a common disease in many soybean-growing areas of the world and is controlled by a single recessive gene (rxp gene) commonly found in many conventional glyphosate-sensitive soybean cultivars. Since glyphosate-tolerant cultivars are commonly planted today, there has been no information about whether these new cultivars have bacterial pustule resistance. The goal of this study was to screen glyphosate-tolerant soybean cultivars for resistance to X. axonopodis pv. glycines. Three experiments were completed to evaluate resistance. In experiment 1, 525 commercial glyphosate-tolerant cultivars from 2001 were inoculated with X. axonopodis pv. …

Cross-Talk In The Gut, Jennifer E. Dinalo, David A. Relman

Faculty and Staff Publications

Modulation of host signaling by the products of microbial activity in the gut may affect weight gain and fat formation.

Failure Of E. Coli Bacteria To Induce Preterm Delivery In The Rat, Emmet Hirsch, Yana Filipovich, Roberto Romero

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

We sought to develop a model of bacterially induced preterm delivery in rats to parallel similar models in mice.

Methods

Female Sprague-Dawley rats on day 17 of gestation (normal term = 21–22 days) were inoculated into the uterus with either 2 × 10⁹ – 7 × 10¹⁰ killed E. coli organisms, 1 – 4 × 10⁸ live E. coli or sterile solution. These inoculations were made either via trans-cervical catheter or by direct intrauterine injection at laparotomy. Animals were then observed for delivery for variable periods up to term. Necropsies were performed and fetal viability …

Afforestation Alters The Composition Of Functional Genes In Soil And Biogeochemical Processes In South American Grasslands, Sean T. Berthrong, Christopher W. Schadt, Gervasio Piñeiro, Robert B. Jackson

Scholarship and Professional Work - LAS

Soil microbes are highly diverse and control most soil biogeochemical reactions. We examined how microbial functional genes and biogeochemical pools responded to the altered chemical inputs accompanying land use change. We examined paired native grasslands and adjacent Eucalyptus plantations (previously grassland) in Uruguay, a region that lacked forests before European settlement. Along with measurements of soil carbon, nitrogen, and bacterial diversity, we analyzed functional genes using the GeoChip 2.0 microarray, which simultaneously quantified several thousand genes involved in soil carbon and nitrogen cycling. Plantations and grassland differed significantly in functional gene profiles, bacterial diversity, and biogeochemical pool sizes. Most grassland …

A Global Meta-Analysis Of Soil Exchangeable Cations, Ph, Carbon, And Nitrogen With Afforestation, Sean T. Berthrong, Esteban G. Jobbagy, Robert B. Jackson

Scholarship and Professional Work - LAS

Afforestation, the conversion of non-forested lands to forest plantations, can sequester atmospheric carbon dioxide, but the rapid growth and harvesting of biomass may deplete nutrients and degrade soils if managed improperly. The goal of this study is to evaluate how afforestation affects mineral soil quality, including pH, sodium, exchangeable cations, organic carbon, and nitrogen, and to examine the magnitude of these changes regionally where afforestation rates are high. We also examine potential mechanisms to reduce the impacts of afforestation on soils and to maintain long-term productivity.

Across diverse plantation types (153 sites) to a depth of 30 cm of mineral …

Compensatory Evolution Of Gene Regulation In Response To Stress By Escherichia Coli Lacking Rpos, Daniel M. Stoebel, Karsten Hokamp, Michael S. Last, Charles J. Dorman

All HMC Faculty Publications and Research

The RpoS sigma factor protein of Escherichia coli RNA polymerase is the master transcriptional regulator of physiological responses to a variety of stresses. This stress response comes at the expense of scavenging for scarce resources, causing a trade-off between stress tolerance and nutrient acquisition. This trade-off favors non-functional rpoS alleles in nutrient-poor environments. We used experimental evolution to explore how natural selection modifies the regulatory network of strains lacking RpoS when they evolve in an osmotically stressful environment. We found that strains lacking RpoS adapt less variably, in terms of both fitness increase and changes in patterns of transcription, than …

X4 Human Immunodeficiency Virus Type 1 Gp120 Down-Modulates Expression And Immunogenicity Of Codelivered Antigens, Avi-Hai Hovav, Michael Santosuosso, Maytal Bivas-Benita, Andre Plair, Alex Cheng, Mazal Elnekave, Elda Righi, Tao Chen, Satoshi Kashiwagi, Michael W. Panas, Shi-Hua Xiang, Karina Furmanov, Norman L. Letvin, Mark C. Poznansky

Nebraska Center for Virology: Faculty Publications

In order to increase the immune breadth of human immunodeficiency virus (HIV) vaccines, strategies such

as immunization with several HIV antigens or centralized immunogens have been examined. HIV-1 gp120

protein is a major immunogen of HIV and has been routinely considered for inclusion in both present and

future AIDS vaccines. However, recent studies proposed that gp120 interferes with the generation of immune

response to codelivered antigens. Here, we investigate whether coimmunization with plasmid-encoded gp120

alters the immune response to other coadministered plasmid encoded antigens such as luciferase or ovalbumin

in a mouse model. We found that the presence of gp120 …

Identification And Characterization Of A New Kaposi’S Sarcoma-Associated Herpesvirus Replication And Transcription Activator (Rta)- Responsive Element Involved In Rta-Mediated Transactivation, Hui-Ju Wen, Veenu Minhas, Charles Wood

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) replication and transcription activator (RTA) is well established as a key transcriptional activator that regulates the KSHV life cycle from latency to lytic replication. It is expressed immediately after infection and activates a number of viral genes leading to virus replication. The RTA-responsive element (RRE) in the RTA target gene promoters is critical for RTA to mediate this transactivation. A number of non-conserved RREs have been identified in various RTA-responsive promoters, and AT-rich sequences have been proposed to serve as RTA targets, but no consensus RRE sequence has been identified so far. Two nonconserved RREs (RRE1 …

Use Of Average Mutual Information For Studying Changes In Hiv Populations, Khalid Sayood, Federico Hoffman, Charles Wood

Nebraska Center for Virology: Faculty Publications

Average mutual information (AMI) has been used in a number of applications in bioinformatics. In this paper we present its use to study genetic changes in populations; in particular populations of HIV viruses. Disease progression of HIV-1 infection in infants can be rapid resulting in death within the the first year, or slow, allowing the infant to survive beyond the first year. We study the development of rapid and slow progressing HIV population using AMI charts based on average mutual information among amino acids in the env gene from a population of 1142 clones derived from seven infants with slow …

Comparison Of Replication-Competent, First Generation, And Helper-Dependent Adenoviral Vaccines, Eric A. Weaver, Pramod N. Nehete, Stephanie S. Buchl, Julien S. Senac, Donna Palmer, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

All studies using human serotype 5 Adenovirus (Ad) vectors must address two major obstacles: safety and the presence of pre-existing neutralizing antibodies. Helper-Dependent (HD) Ads have been proposed as alternative vectors for gene therapy and vaccine development because they have an improved safety profile. To evaluate the potential of HD-Ad vaccines, we compared replication-competent (RC), first-generation (FG) and HD vectors for their ability to induce immune responses in mice. We show that RC-Ad5 and HD-Ad5 vectors generate stronger immune responses than FG-Ad5 vectors. HD-Ad5 vectors gave lower side effects than RC or FG-Ad, producing lower levels of tissue damage and …

Host And Seasonal Effects On The Infection Dynamics Of Skrjabinoptera Phrynosoma (Ortlepp) Schulz, 1927, A Parasitic Nematode Of Horned Lizards, Kathryn Claire Hilsinger

College of Graduate Studies: Theses & Dissertations

Author's Abstract: Skrjabinoptera phrynosoma (Ortlepp) Schulz, 1927 is a common parasitic nematode of horned lizards. The life cycle of S. phrynosoma was described by Lee in 1957, but has received little attention since. The present study addressed effect of season as well as host characteristics on the infection dynamics in lizard hosts. In the Alvord Basin in southeastern Oregon, S. phrynosoma were collected from Phrynosoma platyrhinos Gerard 1852 horned lizards via stomach flushes, cloaca flushes and fecal pellet collections. Parasite load variables (number of nematodes per host, length of those nematodes, and total worm burden (ΣL)) were analyzed within three …

The Molecular Identification Of Non Tuberculosis Mycobacteria (Ntm) From Clinical And Water Samples., Anne Curtin

Theses

Nontuberculosis Mycobacteria (NTM) are now considered a major source of opportunistic infection in immunocompromised patients. Reliable and rapid identification of NTM species is of the upmost importance for patient treatment regimes. Firstly, this study looked at the epidemiological trends of a small number of NTM isolates (n=50) from a large teaching hospital in Southern Ireland Cork University Hospital (C.U.H.). We found that 85% of clinical isolates were sampled from the respiratory tract, which is not unusual as the majority of samples analysed in the hospital lab originated from sputum samples. Also, the majority of patients were 59 years of age …

Generation And Maintenance Of Protective Igm Responses During Intracellular Bacterial Infection, Rachael Denise Racine

Legacy Theses & Dissertations (2009 - 2024)

It is widely accepted that IgM provides the first line of defense against during microbial infection prior to the generation of high-affinity, isotype-switched antibodies, which is the hallmark of long-lived lived immunity and immunological memory. The overall objective of these studies was to address the role of IgM in the generation and maintenance of protective immunity during intracellular bacterial infection. We have identified a population of CD11clo plasmablasts that were responsible for nearly all of the antigen-specific IgM production in the spleen. Moreover, selective depletion of the CD11c-expressing B cells during acute infection resulted in a complete loss in the …

Effect Of Anti-Lipopolysaccharide Iga Antibodies On The Virulence And Physiology Of Salmonella Enterica And Shigella Flexneri, Stephen J. Forbes

Legacy Theses & Dissertations (2009 - 2024)

Secretory IgA (SIgA) antibodies directed against the serotype-specific, O-antigen of lipopolysaccharide (LPS) are the primary determinants of mucosal immunity to enteric bacterial pathogens, including of Salmonella enterica serovar Typhimurium and Shigella flexneri. While the singular importance of SIgA in preventing enteric infections is recognized, the underlying mechanisms by which these antibodies protect the mucosal epithelium remains poorly understood. In this study, I demonstrated that Sal4, a protective, anti-LPS specific monoclonal IgA, is a potent inhibitor of S. Typhimurium flagella-based motility and type three secretion (T3S) mediated entry into epithelial cells. Sal4's effects on motility and invasion occurred rapidly (<15 min), and were independent of agglutination. I also present evidence the protective anti-LPS, monoclonal IgA, IgAC5, reduced S. flexneri T3S of IpaB and IpaC. Concurrent with the IgA-induced reduction in T3S, there was a decrease in both the proton motive force and ATP levels in both bacterial species examined. I also report that Sal4 and IgAC5 have effects on the bacterial envelope. Scanning, transmission, and cyro-electron microscopy revealed dramatic antibody-mediated alterations in the topology of the outer membrane (OM) of S.Typhimurium and S. flexneri. Furthermore, Sal4-treatment caused a ~5 fold increase in O-antigen, and elevated levels of lipid A, released into culture supernatants, consistent with the loss of LPS. Correspondingly, the OM of antibody-treated bacteria was ~50% more permeable than control cells. Based on these data, I proposed that Sal4 binding to the LPS destabilizes the outer leaflet of the OM of S. Typhimurium, thereby compromising the integrity of the bacterial envelope, disrupting bioenergetics by physical and/or mechanical stress, and arresting both flagella-based motility and T3S. This study reveals a previously unrecognized capacity of SIgA to "disarm" enteric pathogens in mucosal secretions, thereby preventing colonization and invasion of the intestinal epithelium.

The Impact Of Environment On Virulence Of The Pathogenic Yeast Cryptococcus Gattii, Deborah Jean Springer

Legacy Theses & Dissertations (2009 - 2024)

Four serotypes of Cryptococcus are responsible for most human and animal infections. C. gattii , serotype B and C, are the primary the causative agent of cryptococcosis in immune competent individuals whilst, C. neoformans var. neoformans serotype D, and C. neoformans var. grubii serotype A are most prevalent in immunocompromised hosts world-wide. C. gattii is recognized as a species distinct from C. neoformans based on differences in clinical manifestations, morphology, biological characteristics, and environmental niche. We used the plant model Arabidopsis thaliana plants and plant derived substrates as a model to explore C. gattii interactions in its ecological niche. C. …

Multiple Antibiotic Resistant Staphylococcus Spp. In Environmental Settings, Stephen Shost

Legacy Theses & Dissertations (2009 - 2024)

Ninety staphylococci carrying the mecA gene, including 17 strains of methicillin-resistant Staphylococcus aureus (MRSA), were isolated from environmental settings within New York State. Waterborne staphylococci harboring mecA were isolated from multiple sources: the Hudson River near a combined sewage overflow; urban streams; freshwater and marine beaches; a swimming pool; swimming pool decks; combined sewage; as well as wastewater treatment plant (WWTP) primary sewage influent, mixed liquor, aeration water, and final (unchlorinated) effluent. Environmental MRSA strains were isolated from beach water (n=3); swimming pool deck water (n=1); Hudson River water (n=2); combined sewage (n=3); as well as wastewater treatment plant mixed …

Identification Of B-Cell Epitopes On Domain 4 Of Anthrax Protective Antigen, Cassandra D. Kelly-Cirino

Legacy Theses & Dissertations (2009 - 2024)

Protective Antigen (PA) is the receptor binding subunit common to both Lethal (LT) and Edema (ET) toxins, which contribute to the mortality associated with Bacillus anthracis infection. While recombinant PA (rPA) is likely to be an important constituent of second generation anthrax vaccines, evaluating the effectiveness of candidate vaccines is currently difficult, because the specific B cell epitopes involved in toxin neutralization have not been completely defined. The only well characterized antibody, 14B7, has been shown to disrupt the association of PA with the anthrax toxin receptors (ATR) by binding to domain 4 of PA. I hypothesized that other domain …

Cd20 Positivity In Classical Hodgkin's Lymphoma: Diagnostic Challenge Or Targeting Opportunity., Muhammad Abrar Barakzai, Shahid Ahmed

Department of Pathology and Laboratory Medicine

BACKGROUND:It is now well established that Hodgkin cells are clonal B cells with a CD30 and CD15 phenotype. However, on immunohistochemistry, in our experience and the experience of others, CD20 positivity in an otherwise typical classical Hodgkin's Lymphoma is not uncommon and if associated with CD15 negativity poses a potential diagnostic trap and is likely to be called B-NHL.
OBJECTIVE:To assess the frequency of B-cell related antigens CD20 and CD79a in classical Hodgkin's Lymphoma.
MATERIALS AND METHODS:A total of 91 consecutive cases of classical Hodgkin's Lymphoma were analyzed for co-expression of CD20 and CD79a. Both males and …

Development Of A Gene Silencing Dna Vector Derived From A Broad Host Range Geminivirus, Edward M. Golenberg, D Noah Sather, Leandria C. Hancock, Kenneth J. Buckley, Natalie M. Villafranco, David M. Bisaro

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Gene silencing is proving to be a powerful tool for genetic, developmental, and physiological analyses. The use of viral induced gene silencing (VIGS) offers advantages to transgenic approaches as it can be potentially applied to non-model systems for which transgenic techniques are not readily available. However, many VIGS vectors are derived from Gemini viruses that have limited host ranges. We present a new, unipartite vector that is derived from a curtovirus that has a broad host range and will be amenable to use in many non-model systems.

Results

The construction of a gene silencing vector derived from the …

Incorporation Of Membrane-Bound, Mammalian-Derived Immunomodulatory Proteins Into Influenza Whole Virus Vaccines Boosts Immunogenicity And Protection Against Lethal Challenge, Andrew S. Herbert, Lynn Heffron, Roy Sundick, Paul C. Roberts

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Influenza epidemics continue to cause morbidity and mortality within the human population despite widespread vaccination efforts. This, along with the ominous threat of an avian influenza pandemic (H5N1), demonstrates the need for a much improved, more sophisticated influenza vaccine. We have developed an in vitro model system for producing a membrane-bound Cytokine-bearing Influenza Vaccine (CYT-IVAC). Numerous cytokines are involved in directing both innate and adaptive immunity and it is our goal to utilize the properties of individual cytokines and other immunomodulatory proteins to create a more immunogenic vaccine.

Results

We have evaluated the immunogenicity of inactivated cytokine-bearing influenza …

Results From A Mathematical Model For Human Monocytic Ehrlichiosis, H. Gaff, L. Gross, E. Schaefer

Biological Sciences Faculty Publications

Human monocytic ehrlichiosis (Ehrlichia chaffeensis), HME, is a tick-transmitted, rickettsial disease that has recently increased substantially in the USA from 142 reported cases in 2001 to 506 reported cases in 2005 [1,2]. There have been increasing surveys of tick populations over the past 10 years that have in turn supported the development of models for tick-borne disease transmission. Resulting HME models [3] suggest the importance of metapopulation structures, landscape environment parameters and periodic climatic effects in predicting the dynamics of HME transmission and the efficacy of control efforts, such as the reduction of the tick population through acaricide …

Peripheral Dendritic Cells Are Essential For Both The Innate And Adaptive Antiviral Immune Responses In The Central Nervous System, Christina D. Steel, Suzanna M. Hahto, Richard P. Ciavarra

Biological Sciences Faculty Publications

Intranasal application of vesicular stomatitis virus (VSV) causes acute infection of the central nervous system (CNS). However, VSV encephalitis is not invariably fatal, suggesting that the CNS may contain a professional antigen-presenting cell (APC) capable of inducing or propagating a protective antiviral immune response. To examine this possibility, we first characterized the cellular elements that infiltrate the brain as well as the activation status of resident microglia in the brains of normal and transgenic mice acutely ablated of peripheral dendritic cells (DCs) in vivo. VSV encephalitis was characterized by a pronounced infiltrate of myeloid cells (CD45^highCD11b^{+ …}

Retrocyclin, A Potent Hiv-1 Entry Inhibitor, Nitya Venkataraman

Electronic Theses and Dissertations

Human immununodeficiency virus (HIV) infection is the leading cause of death due to viral infections worldwide. In the absence of an effective vaccine or consistent male condom use, there is a clear need for female-controlled preventatives such as topical vaginal microbicides. Recent attention has been focused on developing natural antimicrobial peptides, as anti-retroviral microbicides. Increasing evidence suggests that cationic antimicrobial peptides such as defensins are effective HIV-1 inhibitors. Human alpha- and beta-defensins contribute substantially to innate immune defenses against microbial and viral infections. Certain nonhuman primates also produce theta-defensins – 18 residue cyclic peptides that are potent HIV-1 entry inhibitors. …