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Investigation Of Competence Heterogeneity In Streptococcus Milleri Group Clinical Isolates, Anne-Marie G. Lacroix 2014 McMaster University

Investigation Of Competence Heterogeneity In Streptococcus Milleri Group Clinical Isolates, Anne-Marie G. Lacroix

Open Access Dissertations and Theses

The Streptococcus Milleri/Anginosus group (SMG) includes Streptococcus anginosus, Streptococcus constellatus and Streptococcus intermedius. The SMG is found in healthy individuals but these bacteria are most known clinically for being associated with invasive disease and more recently, airway infections including cystic fibrosis (CF). The SMG like many other streptococci are naturally competent, being able to actively bind, uptake and integrate extracellular DNA. Competence regulation involves a competence-stimulating peptide (CSP) derived from the ComC precursor and a two- component signaling system (a histidine kinase ComD and its response regulator ComE). In this study, I examined the distribution of CSP/ComD sequences ...


Characterization Of Protein-Protein Interactions Mediated By The Second Exon Of The Varicella-Zoster Virus Orf45/42 Terminase Subunit, Elizabeth A. Syster-Clevenger 2014 Indiana University – Purdue University Fort Wayne

Characterization Of Protein-Protein Interactions Mediated By The Second Exon Of The Varicella-Zoster Virus Orf45/42 Terminase Subunit, Elizabeth A. Syster-Clevenger

Master's Theses

Varicella-zoster virus (VZV), a member of the Herpesviridae, is ubiquitous human pathogen with significant morbidity and mortality in healthy and immunocompromised individuals. Primary infection causes a systemic viremia and skin rash known as varicella, and more commonly referred to as chickenpox. Latency is established in the nervous system during primary infection and can reactivate to cause zoster, more commonly known as shingles. Current treatments for VZV infection target viral DNA replication, primarily the DNA polymerase. However, novel small molecule inhibitors that target other viral replication processes, for example viral DNA encapsidation, offer additional therapeutic options. Seven conserved open reading frames ...


Growing Conditions For Algae, Angeles Mora, Tamar Melkonian, Alejandro Calderon-Urrea 2014 California Polytechnic State University

Growing Conditions For Algae, Angeles Mora, Tamar Melkonian, Alejandro Calderon-Urrea

STEM Teacher and Researcher (STAR) Program Posters

With the growing demands of water in California and the increasing cost of fossil fuels to operate water-cleaning equipment, Algae was cultivated in different concentrations of Nitrogen, Phosphorus, and Potassium (NPK) during different trails to identify the best growing conditions for the removal water contaminates. Before testing algae in waste water, the Algae: Dunaliella Primolecta, Chlorella Vulgaris, and Scenedesmus Dimorphus were cultivated in four different media containing distilled water and plant vitamins. The different mediums used include: Orchid Grow More (20-20-20), Miracle Grow (30-10-10), Murashige & Skoog, and Orchid Bloom Boster (11-35-15). As a result of the investigation, the algae, Scenedesmus ...


Phylogenetic Diversity Of Microbial Isolates From The Mars Pathfinder, Kyla BradyLong, Adriana Blachowicz, Parag Vaishampayan, James N. Benardini, Wayne Schubert 2014 California Polytechnic State University

Phylogenetic Diversity Of Microbial Isolates From The Mars Pathfinder, Kyla Bradylong, Adriana Blachowicz, Parag Vaishampayan, James N. Benardini, Wayne Schubert

STEM Teacher and Researcher (STAR) Program Posters

As spacecraft are sent to different planets, they take with them microscopic pieces of life from Earth. It is the task of the Biotechnology and Planetary Protection Group to keep as much of this life off other planets as possible as well as document any life that may have been sent. During the construction of the Mars Pathfinder, samples were collected from various locations on the spacecraft to test for contamination. These samples were then isolated, grown, documented, preserved and their 16S rRNA genes were sequenced for identification. The 16S rRNA gene sequence is utilized because it is a highly ...


Detection Of Microbial Catecholamines In A Model Wound Environment, Ryan F. Wasurick 2014 California Polytechnic State University

Detection Of Microbial Catecholamines In A Model Wound Environment, Ryan F. Wasurick

STEM Teacher and Researcher (STAR) Program Posters

Chronic wounds are defined as an injury that does not heal in a predictable pattern or time frame. The healing process is composed of specific stages and chronic wounds have been interrupted in one or more stages of this process. This project focuses on the bacterial component of an infected wound, specifically on the catecholamines influencing the bacteria in the wound site. The assay developed in this experiment is designed to optimally grow bacteria in a simulated eukaryotic wound environment, and evaluate biofilm expression and catecholamine production of the bacteria. Bacteria used in this study are Staphylococcus aureus and Pseudomonas ...


The Show Cave Of Diros Vs. Wild Caves Of Peloponnese, Greece - Distribution Patterns Of Cyanobacteria, Vasiliki Lamprinou, Daniel B. Danielidis, Adriani Pantazidou, Alexandra Oikonomou, Athena Economou-Amilli 2014 University of South Florida

The Show Cave Of Diros Vs. Wild Caves Of Peloponnese, Greece - Distribution Patterns Of Cyanobacteria, Vasiliki Lamprinou, Daniel B. Danielidis, Adriani Pantazidou, Alexandra Oikonomou, Athena Economou-Amilli

International Journal of Speleology

The karst cave ‘Vlychada’of Diros, one of the oldest show caves in Peloponnese, sustains extended phototrophic biofilms on various substrata – on rocks inside the cave including speleothems, and especially near the artificial lighting installation (‘Lampenflora’). After a survey of the main abiotic parameters (Photosynthetically Active Radiation -PAR, Temperature -T, Relative Humidity -RH, Carbon Dioxide -CO2) three clusters of sampling sites were revealed according to Principal Component Analysis (PCA): i) the water gallery section predominately influenced by CO2, ii) the dry passages influenced by RH and PAR, and iii) the area by the cave exit at the dry ...


Ammonia-Oxidizing Bacteria And Archaea Under Continuous Maize: The Influence Of Tillage, N Input And Aggregation On Abundance And Community Composition, Lauren Segal 2014 University of Nebraska - Lincoln

Ammonia-Oxidizing Bacteria And Archaea Under Continuous Maize: The Influence Of Tillage, N Input And Aggregation On Abundance And Community Composition, Lauren Segal

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Nitrification involves the oxidation of ammonium (NH4+) and is an important component of the overall N cycle. Nitrification occurs in two steps; first by oxidizing ammonium to nitrite, and then to nitrate. The first step is often the rate limiting step. Until recently ammonia-oxidizing bacteria (AOB) were thought to be the sole contributors to this process; however, the discovery of crenarchaeota, ammonia-oxidizing archaea (AOA), in marine environments has led to further study of their role in nitrification. Current literature supports the dominance of AOA over AOB in terrestrial ecosystems; however, little is known about what drives their abundance. To ...


Probiotic Therapy For Heart Failure: Investigating The Potential Anti-Hypertrophic Properties Of Probiotics, Grace L. Ettinger 2014 Western University

Probiotic Therapy For Heart Failure: Investigating The Potential Anti-Hypertrophic Properties Of Probiotics, Grace L. Ettinger

University of Western Ontario - Electronic Thesis and Dissertation Repository

Heart failure patients face a five-year 50% mortality rate, due to impaired cardiac function and hypertrophy of the heart. Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. Considering the established cardiovascular benefits of some probiotics, including reduction of cholesterol and hypertension, it was hypothesized that probiotics can improve outcomes of heart failure. Probiotics or controls were administered orally to an animal model for heart failure. Those receiving probiotics showed a significant improvement in cardiac hypertrophy and an attenuation of heart failure compared to control. No changes in gut microbial composition occurred ...


Understanding The Factors Affecting Microbiological Quality Of Wheat Milled Products: From Wheat Fields To Milling Operations, Luis E. Sabillón Galeas 2014 University of Nebraska - Lincoln

Understanding The Factors Affecting Microbiological Quality Of Wheat Milled Products: From Wheat Fields To Milling Operations, Luis E. Sabillón Galeas

Dissertations & Theses in Food Science and Technology

Although regarded as a low-risk commodity, wheat flour-based mixes have been implicated in several food safety incidents. The present thesis is a compilation of five scientific manuscripts on the effect of weather variation, milling steps and implementation of pre-milling interventions on the microbiological quality and safety of wheat and milled products. The first manuscript is a review of the microbiological quality and safety of wheat-based products. Despite the low water activity, wheat flour may harbor dormant but viable microorganisms, which could lead to safety concerns when flour is used to produce refrigerated dough products. The second manuscript illustrates the effect ...


Fty720 (Fingolimod) Provides Insight Into The Molecular Mechanisms Of Multiple Sclerosis, Madelyn Elizabeth Crawford 2014 University of Tennessee, Knoxville

Fty720 (Fingolimod) Provides Insight Into The Molecular Mechanisms Of Multiple Sclerosis, Madelyn Elizabeth Crawford

Pursuit - The Journal of Undergraduate Research at the University of Tennessee

Multiple sclerosis (MS) is a neurodegenerative disorder caused by a prolonged immune- mediated inflammatory response that targets myelin. Nearly all of the drugs approved for the treatment of MS are general immunosuppressants or only function in symptom management. The oral medication fingolimod, however, is reported to have direct therapeutic effects on cells of the central nervous system in addition to immunomodulatory functions. Fingolimod is known to interact with sphingosine-1-phosphate (S1P) receptors, and the most widely- accepted theory for its mechanism of action is functional antagonism of the receptor. This review examines significant neuromodulatory effects achieved by functional antagonism of the ...


The Role Of The N-Terminus On The Enzymatic Activity Of Dutpase From Dictyostelium Discoideum, Kyle C. Varon 2014 University of Nebraska - Lincoln

The Role Of The N-Terminus On The Enzymatic Activity Of Dutpase From Dictyostelium Discoideum, Kyle C. Varon

Dissertations and Theses in Biological Sciences

The enzyme deoxyuridine triphosphatase (dUTPase) (EC 3.6.1.23) converts dUTP to dUMP, thus shifting the dUTP to dUMP ratio in the cell. The molecule dUTP is subject to mis-incorporation into DNA due to lack of distinguishing by DNA polymerase. Uracil incorporation can be repaired with base excision repair mechanisms but may create overwhelming DNA strand breaks proving to be detrimental to the cell. Most dUTPases of eukaryotes are homotrimeric and contain five highly conserved motifs responsible for catalysis and substrate binding. Many dUTPases of eukaryotes possess a leading and core region in their sequence. The core region is ...


Investigating The Viability Of Two Stenotrophomonas Maltophilia Isolates After Air-Drying, Samantha Lane, Joanna Brooke 2014 DePaul University

Investigating The Viability Of Two Stenotrophomonas Maltophilia Isolates After Air-Drying, Samantha Lane, Joanna Brooke

DePaul Discoveries

Abstract

Stenotrophomonas maltophilia is a water-borne infectious bacterium that is found in both clinical (hospitals) and non-clinical environments. This human pathogen is commonly recovered from respiratory tract infections. A recent study at a hospital in Taiwan suggested that dry patient charts can serve as a vehicle of transmission of this bacterium7. As S. maltophilia is not commonly isolated from dry surfaces, this current study tested the hypothesis that this pathogen can remain viable for some time on a dry surface. This study was designed to determine how long S. maltophilia could remain viable after air-drying by observing culture growth ...


Characterizing The Response Of Multidrug-Resistant Klebsiella Pneumoniae Species To The Application Of A Phage Cocktail, Steven Liu 2014 California Polytechnic State University

Characterizing The Response Of Multidrug-Resistant Klebsiella Pneumoniae Species To The Application Of A Phage Cocktail, Steven Liu

Symposium

Project Summary: The application of bacteriophages to treat bacterial infections is known as phage therapy, which takes advantage of bacteriophage’s natural ability to infect and lyse bacterial hosts. Phages have been shaped by billions of years of evolution to be highly specialized deliverers of bactericidal agents to the cytoplasm of their target bacteria. Ever since discovery of bacteriophages in 1915, phage therapy was recognized as a potentially powerful tool for eliminating bacterial infections. The effectiveness of phage therapy can be increased by creating a mixture of multiple phages to target a wider variety of bacterial strains. Furthermore, phage therapy ...


Sub-Inhibitory Antibiotics Enhance Virulence, Persistence, And Pathogenesis Of Uropathogens, Lee W. Goneau 2014 Western University

Sub-Inhibitory Antibiotics Enhance Virulence, Persistence, And Pathogenesis Of Uropathogens, Lee W. Goneau

University of Western Ontario - Electronic Thesis and Dissertation Repository

In addition to their bactericidal effects, antibiotics are potent signal mediators at sub-inhibitory levels in the environment. The ability to modulate community structure in this niche raises concerns over their capacity to influence pathogenesis in patients during antibiotic therapy. This concept forms the basis of this thesis, and is explored using models of prophylactic therapy for recurrent urinary tract infection (UTI) management.

Sub-inhibitory ciprofloxacin, ampicillin, and gentamicin were found to augment virulence in vitro, increasing adherence and urothelial cell invasion in uropathogenic Escherichia coli (UPEC) and Staphylococcus saprophyticus. In addition, biofilm formation was increased, and swarming motility decreased. In UPEC ...


The Antimicrobial, Mechanical, Physical And Structural Properties Of Chitosan-Gallic Acid Films, Xiuxiu Sun, Zhe Wang, Hoda Kadouh, Kequan Zhou 2014 Wayne State University

The Antimicrobial, Mechanical, Physical And Structural Properties Of Chitosan-Gallic Acid Films, Xiuxiu Sun, Zhe Wang, Hoda Kadouh, Kequan Zhou

Nutrition and Food Science Faculty Research Publications

Chitosan films incorporated with various concentrations of gallic acid were prepared and investigated for antimicrobial, mechanical, physical and structural properties. Four bacterial strains that commonly contaminate food products were chosen as target bacteria to evaluate the antimicrobial activity of the prepared gallic acid-chitosan films. The incorporation of gallic acid significantly increased the antimicrobial activities of the films against Escherichia coli, Salmonella typhimurium, Listeria innocua and Bacillus subtilis. Chitosan films incorporated with 1.5 g/100 g gallic acid showed the strongest antimicrobial activity. It was also found that tensile strength (TS) of chitosan film was significantly increased when incorporating 0 ...


Chlorovirus Skp1 And Core Ankyrin-Repeat Protein Interplay And Mimicry Of Cellular Ubiquitin Ligase Machinery, Eric Andrew Noel 2014 University of Nebraska - Lincoln

Chlorovirus Skp1 And Core Ankyrin-Repeat Protein Interplay And Mimicry Of Cellular Ubiquitin Ligase Machinery, Eric Andrew Noel

Dissertations and Theses in Biological Sciences

The ubiquitin-proteasome system is a common target of several unrelated viruses that have evolved convergent strategies to redirect host ubiquitin machinery to serve their own needs. Members of the genus Chlorovirus, a group of large dsDNA viruses that infect certain freshwater chlorella-like green algae, encode a conserved Skp1 homolog and ankyrin-repeat (ANK) proteins, some of which contain C-terminal domains characteristic of cellular F-boxes or related viral PRANC domains. These observations suggested that this unique combination of chlorovirus proteins either interact with or imitate the key components of the SCF (Skp1-Cul1-F-box) ubiquitin ligases. Using mass spectrometry, we identified two functional classes ...


Characterization Of Corynebacterium Pseudotuberculosis Biovar Equi Isolates Obtained From Cal Poly Horses And Review Of Application Of Transposons To Better Prevent Pigeon Fever In Horses, Irene Hasen 2014 California Polytechnic State University

Characterization Of Corynebacterium Pseudotuberculosis Biovar Equi Isolates Obtained From Cal Poly Horses And Review Of Application Of Transposons To Better Prevent Pigeon Fever In Horses, Irene Hasen

Animal Science

No abstract provided.


The Effect Of Nutrition On The Microbiome In Pregnant Women And The Use Of Micronutrient Supplemented Probiotic Yogurt To Improve Outcomes, Megan Kathleen Enos 2014 Western University

The Effect Of Nutrition On The Microbiome In Pregnant Women And The Use Of Micronutrient Supplemented Probiotic Yogurt To Improve Outcomes, Megan Kathleen Enos

University of Western Ontario - Electronic Thesis and Dissertation Repository

The aims of this study were to characterize the gut, oral, and vaginal microbiotas of pregnant women with varying nutritional status and to determine if daily supplementation with probiotic yogurt containing Lactobacillus rhamnosus GR-1 and ground Moringa leaves, would ‘normalize’ the microbiota and improve pregnancy outcomes. For the latter, a clinical study was performed in Mwanza, Tanzania, in which consumption of yogurt for 88 ± 31 days, starting from the second trimester, did not result in excess weight gain, altered pregnancy outcomes or increased blood nutrient levels compared to an under-nourished group not taking the yogurt. Ingestion of the probiotic yogurt ...


Identification And Characterization Of Phytoplankton In Barnegat Bay, New Jersey, Nicole L. Elia 2014 Seton Hall University

Identification And Characterization Of Phytoplankton In Barnegat Bay, New Jersey, Nicole L. Elia

Seton Hall University Dissertations and Theses (ETDs)

Barnegat Bay is a marine estuary that encompasses 670-square miles of the eastern coast of New Jersey. The bay serves as a home to thousands of species of plants, animals, and microorganisms. During the summer months, the population of the bay increases from 576,000 to over 1.5 million residents. In 2011, the Barnegat Bay Partnership reported that environmental conditions of the bay are declining due to increased pollutants from nutrient fertilizers and runoff. Increased nitrogen levels have led to eutrophication and proliferation of phytoplankton algal blooms. Harmful algal blooms (HABs) cause a decrease in dissolved oxygen levels in ...


The Use Of Natural Products As Potential Anti-Pseudomonas Agents, Margaret T. Bell 2014 Seton Hall University

The Use Of Natural Products As Potential Anti-Pseudomonas Agents, Margaret T. Bell

Seton Hall University Dissertations and Theses (ETDs)

Pseudomonas is a genus of gram-negative gammaproteobacteria with a large range of diversity. Because of its ability to grow at low temperature, Pseudomonas is a cause of food spoilage. This bacterium is also a very common nosocomial infection of hospital patients. In this study, we investigated the effects of different natural products on Pseudomonas. The products included a polysaccharide, two flavonoids tangeretin and nobiletin and their derivatives, 5’OH-tangeretin and 5’OH-nobiletin, black tea polyphenol – theaflavins (TFs), as well as an herb named Fallopia multiflora (Chinese Knotweed). P. fluorescens and P. aeruginosa were used as model organisms. Antimicrobial effects were ...


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