Open Access. Powered by Scholars. Published by Universities.®

Pathogenic Microbiology Commons

Open Access. Powered by Scholars. Published by Universities.®

Medical Sciences

Institution
Keyword
Publication Year
Publication
Publication Type

Articles 1 - 30 of 33

Full-Text Articles in Pathogenic Microbiology

Space Race, Siri And The Central Dogma: A Contemporary Nursing Analysis Of Antibiotics Resistance, Donovan Lucibello Apr 2019

Space Race, Siri And The Central Dogma: A Contemporary Nursing Analysis Of Antibiotics Resistance, Donovan Lucibello

Nursing Undergraduate Theses

In the age of information, antibiotic resistance is still a black-box problem in clinical practice; pathogens are often defined in terms of which pharmaceuticals are no longer effective, and treatment protocols are prescribed prophylactically; often at strengths that are in excess of what is known about the pathogen’s susceptibilities or even its identity. All antibiotic resistance mechanisms involve the expression of proteins that provide resistance capabilities. These modified proteins should be detectable by analyzing DNA (or RNA intermediates) that code for them in order to determine a pathogen’s threat profile. Next-Generation and nanopore DNA sequencing technologies are capable ...


Cryptococcus Neoformans Cda1 And Its Chitin Deacetylase Activity Are Required For Fungal Pathogenesis, Rajendra Upadhya, Lorina G. Baker, Woei C. Lam, Charles A. Specht, Maureen J. Donlin, Jennifer K. Lodge Nov 2018

Cryptococcus Neoformans Cda1 And Its Chitin Deacetylase Activity Are Required For Fungal Pathogenesis, Rajendra Upadhya, Lorina G. Baker, Woei C. Lam, Charles A. Specht, Maureen J. Donlin, Jennifer K. Lodge

Open Access Articles

Chitin is an essential component of the cell wall of Cryptococcus neoformans conferring structural rigidity and integrity under diverse environmental conditions. Chitin deacetylase genes encode the enyzmes (chitin deacetylases [Cdas]) that deacetylate chitin, converting it to chitosan. The functional role of chitosan in the fungal cell wall is not well defined, but it is an important virulence determinant of C. neoformans Mutant strains deficient in chitosan are completely avirulent in a mouse pulmonary infection model. C. neoformans carries genes that encode three Cdas (Cda1, Cda2, and Cda3) that appear to be functionally redundant in cells grown under vegetative conditions. Here ...


Vancomycin Delays Clindamycin-Induced Fatality In The Hamster Model Of Clostridioides [Clostridium] Difficile Infection, Amelia E. Fox-King, Chrisabelle Mefferd, Jacqueline R. Phan, Nancy O. Nou, Ernesto Abel-Santos, Brian P. Hedlund Oct 2018

Vancomycin Delays Clindamycin-Induced Fatality In The Hamster Model Of Clostridioides [Clostridium] Difficile Infection, Amelia E. Fox-King, Chrisabelle Mefferd, Jacqueline R. Phan, Nancy O. Nou, Ernesto Abel-Santos, Brian P. Hedlund

LSAMP Poster Presentations

Antibiotics can leave the host gut microbiome susceptible to Clostridioides [Clostridium] difficile colonization and lethal toxin production. For instance, clindamycin-induced susceptibility to C. difficile infection (CDI) results in rapid fatality in hamster models, yet vancomycin has been shown to offer increased survival in hamsters challenged with C. difficile. We aim to develop an antibiotic treatment that will facilitate CDI susceptibility without prompt fatality in hamster models. An antibiotic regimen starting with a continuous vancomycin treatment along with a single clindamycin dosage is thought to reduce the major disruption in the indigenous gut microbiome and prevent clindamycin-induced death. Quantitative polymerase chain ...


Nutritional Virulence Of Legionella Pneumophila., Ashley M. Best May 2018

Nutritional Virulence Of Legionella Pneumophila., Ashley M. Best

Electronic Theses and Dissertations

Legionella pneumophila is an environment organism that parasitizes a wide range of protozoa. Growth within the environmental host primes L. pneumophila for infection of human alveolar macrophages when contaminated aerosols are inhaled. Intracellular replication within either host requires the establishment a replicative niche, known as the Legionella-containing vacuole (LCV). Biogenesis of the LCV depends on the type IVb translocation system, the Dot/Icm, to translocation >320 effectors into the host cytosol. Effectors are responsible for preventing lysosome fusion to the LCV, recruitment of ER-derived vesicles to the LCV, and modulation of a plethora of host processes to promote the ...


A Comparison Of Oral And Intravenous Mouse Models Of Listeriosis, Michelle G. Pitts, Sarah E. F. D'Orazio Mar 2018

A Comparison Of Oral And Intravenous Mouse Models Of Listeriosis, Michelle G. Pitts, Sarah E. F. D'Orazio

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Listeria monocytogenes is one of several enteric microbes that is acquired orally, invades the gastric mucosa, and then disseminates to peripheral tissues to cause systemic disease in humans. Intravenous (i.v.) inoculation of mice with L. monocytogenes has been the most widely-used small animal model of listeriosis over the past few decades. The infection is highly reproducible and has been invaluable in deciphering mechanisms of adaptive immunity in vivo, particularly CD8+ T cell responses to intracellular pathogens. However, the i.v. model completely bypasses the gut phase of the infection. Recent advances in generating both humanized mice and murinized bacteria ...


Evolution Of Bordetella Pertussis Genome May Play A Role In The Increased Rate Of Whooping Cough Cases In The United States, Kevin Loftus Jan 2018

Evolution Of Bordetella Pertussis Genome May Play A Role In The Increased Rate Of Whooping Cough Cases In The United States, Kevin Loftus

Senior Honors Projects, 2010-current

Bordetella pertussis is the bacterium responsible for pertussis, a disease commonly referred to as whooping cough. Recently, pertussis has made a resurgence in the U.S. despite high-vaccination coverage. Possible causes of the increased number of pertussis cases include genetic evolution of B. pertussis, increased awareness of the disease, better laboratory diagnostics, and the switch from a whole-cellular (wP) vaccine to an acellular vaccine (aP) in the 1990s. Fortunately, just as B. pertussis is evolving, so is the arsenal of technologies used to understand and combat this pathogenic bacterium. Whole genome sequencing is one technology that helps researchers better understand ...


Comparison Between Listeria Sensu Stricto And Listeria Sensu Lato Strains Identifies Novel Determinants Involved In Infection, Jakob Schardt, Grant Jones, Stefanie Müller-Herbst, Kristina Schauer, Sarah E. F. D'Orazio, Thilo M. Fuchs Dec 2017

Comparison Between Listeria Sensu Stricto And Listeria Sensu Lato Strains Identifies Novel Determinants Involved In Infection, Jakob Schardt, Grant Jones, Stefanie Müller-Herbst, Kristina Schauer, Sarah E. F. D'Orazio, Thilo M. Fuchs

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The human pathogen L. monocytogenes and the animal pathogen L. ivanovii, together with four other species isolated from symptom-free animals, form the "Listeria sensu stricto" clade. The members of the second clade, "Listeria sensu lato", are believed to be solely environmental bacteria without the ability to colonize mammalian hosts. To identify novel determinants that contribute to infection by L. monocytogenes, the causative agent of the foodborne disease listeriosis, we performed a genome comparison of the two clades and found 151 candidate genes that are conserved in the Listeria sensu stricto species. Two factors were investigated further in vitro and in ...


T-Cell Responses Targeting Hiv Nef Uniquely Correlate With Infected Cell Frequencies After Long-Term Antiretroviral Therapy., Allison S Thomas, Kimberley L Jones, Rajesh T Gandhi, Deborah K Mcmahon, Joshua C Cyktor, Dora Chan, Szu-Han Huang, Ronald Truong, Alberto Bosque, Amanda B Macedo, Colin Kovacs, Erika Benko, Joseph J Eron, Ronald J Bosch, Christina M Lalama, Samuel Simmens, Bruce D Walker, John W Mellors, R Brad Jones Sep 2017

T-Cell Responses Targeting Hiv Nef Uniquely Correlate With Infected Cell Frequencies After Long-Term Antiretroviral Therapy., Allison S Thomas, Kimberley L Jones, Rajesh T Gandhi, Deborah K Mcmahon, Joshua C Cyktor, Dora Chan, Szu-Han Huang, Ronald Truong, Alberto Bosque, Amanda B Macedo, Colin Kovacs, Erika Benko, Joseph J Eron, Ronald J Bosch, Christina M Lalama, Samuel Simmens, Bruce D Walker, John W Mellors, R Brad Jones

Microbiology, Immunology, and Tropical Medicine Faculty Publications

HIV-specific CD8+ T-cell responses limit viral replication in untreated infection. After the initiation of antiretroviral therapy (ART), these responses decay and the infected cell population that remains is commonly considered to be invisible to T-cells. We hypothesized that HIV antigen recognition may persist in ART-treated individuals due to low-level or episodic protein expression. We posited that if persistent recognition were occurring it would be preferentially directed against the early HIV gene products Nef, Tat, and Rev as compared to late gene products, such as Gag, Pol, and Env, which have higher barriers to expression. Using a primary cell model of ...


The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry Jul 2017

The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The FeoABC ferrous transporter is a wide-spread bacterial system. While the feoABC locus is regulated by a number of factors in the bacteria studied, we have previously found that regulation of feoABC in Yersinia pestis appears to be unique. None of the non-iron responsive transcriptional regulators that control expression of feoABC in other bacteria do so in Y. pestis. Another unique factor is the iron and Fur regulation of the Y. pestis feoABC locus occurs during microaerobic but not aerobic growth. Here we show that this unique iron-regulation is not due to a unique aspect of the Y. pestis Fur ...


Pas Signaling Mechanisms In Aer And Aer2, Darysbel Garcia Jun 2017

Pas Signaling Mechanisms In Aer And Aer2, Darysbel Garcia

Loma Linda University Electronic Theses, Dissertations & Projects

PAS domains are widespread signal sensors that share a conserved three-dimensional αβ fold that consists of a central β-sheet flanked by several α- helices. The aerotaxis receptor Aer from Escherichia coli and the Aer2 chemoreceptor from Pseudomonas aeruginosa both contain PAS domains. Aer senses oxygen (O2) indirectly via an FAD cofactor bound to its PAS domain, while Aer2 directly binds O2 to its PAS b-type heme cofactor. The Aer and Aer2 PAS domains both interact with a signal transduction domain known as a HAMP domain. The PAS-HAMP arrangement differs between Aer and Aer2, with Aer- PAS residing adjacent to its ...


Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings May 2017

Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings

Undergraduate Honors Theses

More so than ever, Multiple Drug Resistant (MDR) bacteria are on the rise due to overuse of antibiotics along with natural selection for adaptations that enhance drug-resistant properties. One particular bacterial family, Enterobacteriaceae, has been problematic, exhibiting several bacterial members that have developed a precipitous resistance to modern antibiotics and are also primary causative agents of nosocomial, or hospital acquired, infections. Citrobacter freundii (CF) and Enterobacter cloacae (ECL) are two species of the Enterobacteriaceae family causing significant medical concern due to their role in producing numerous opportunistic infections such as bacteremia, lower respiratory tract infections, urinary tract infections, and endocarditis ...


The Making Of A Pathogen: Implications Of Phage Domestication In Acinetobacter Baumannii, Allison Welp Apr 2017

The Making Of A Pathogen: Implications Of Phage Domestication In Acinetobacter Baumannii, Allison Welp

Undergraduate Theses

Mutations and horizontal gene transfer have allowed for rapid evolution of many species of bacteria, allowing them to become more virulent and resistant to antibiotics. As a result of these changes, Acinetobacter baumannii has become one of the most prominent drug-resistant bacteria in hospitals. This nosocomial pathogen is capable of causing a range of infections—from pneumonia to sepsis—and is extremely difficult to eradicate from hospital settings. Despite its current status, this species has not always been apparent in healthcare. The emergence of this organism has been extremely rapid; once an innocuous environmental organism, A. baumannii is now resistant ...


The Effect Of Photoactivated Tmp On Burkholderia Cepacia Biofilms, Reyna G. Osorio, Chandra N. Swiech, Tracy L. Collins Apr 2017

The Effect Of Photoactivated Tmp On Burkholderia Cepacia Biofilms, Reyna G. Osorio, Chandra N. Swiech, Tracy L. Collins

The Research and Scholarship Symposium

Burkholderia cepacia is an opportunistic pathogen that causes infections in immunocompromised individuals such as cystic fibrosis patients. B. cepacia infections are typically characterized by the formation of complex communities of cells known as biofilms. Because B. cepacia biofilms are difficult to eradicate using antibiotics, it is important to pursue alternative treatment methods. Photodynamic therapy (PDT) is a type of therapy that uses light, a photosensitizer, and oxygen to elicit cell death through the production of reactive oxygen species. PDT has been shown in previous studies to be successful in killing both Pseudomonas aeruginosa and Staphylococcus aureus. In this study, we ...


Ticks Elicit Variable Fibrinogenolytic Activities Upon Feeding On Hosts With Different Immune Backgrounds, Ashish Vora, Vikas Taank, John F. Anderson, Durland Fish, Daniel E. Sonenshine, John D. Catravas, Hameeda Sultana, Girish Neelakanta Mar 2017

Ticks Elicit Variable Fibrinogenolytic Activities Upon Feeding On Hosts With Different Immune Backgrounds, Ashish Vora, Vikas Taank, John F. Anderson, Durland Fish, Daniel E. Sonenshine, John D. Catravas, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Ticks secrete several anti-hemostatic factors in their saliva to suppress the host innate and acquired immune defenses against infestations. Using Ixodes scapularis ticks and age-matched mice purchased from two independent commercial vendors with two different immune backgrounds as a model, we show that ticks fed on immunodeficient animals demonstrate decreased fibrinogenolytic activity in comparison to ticks fed on immunocompetent animals. Reduced levels of D-dimer (fibrin degradation product) were evident in ticks fed on immunodeficient animals in comparison to ticks fed on immunocompetent animals. Increased engorgement weights were noted for ticks fed on immunodeficient animals in comparison to ticks fed on ...


Dynamic Host-Pathogen Interactions Result In Fungal Epitope Unmasking, Alex Hopke Aug 2016

Dynamic Host-Pathogen Interactions Result In Fungal Epitope Unmasking, Alex Hopke

Electronic Theses and Dissertations

Molecular camouflage is used by a diverse set of pathogens to disguise their identity and avoid recognition by protective host receptors. The opportunistic fungal pathogen Candida albicans is a good example, as it masks the inflammatory component β-glucan in its cell wall to evade detection by the immune receptor Dectin-1. Interestingly, it has been seen that β-glucan becomes unmasked during infection in vivo, though the underlying mechanisms remained unclear. Exposure levels of this epitope may be important, as Dectin-1 mediates protection from some strains of C. albicans and alterations in the organization and composition of the Candida cell wall can ...


The Activity Of Antimicrobial Surfaces Varies By Testing Protocol Utilized, Matias D. Campos, Paola C. Zucchi, Ann Phung, Steven N. Leonard, Elizabeth B. Hirsch Aug 2016

The Activity Of Antimicrobial Surfaces Varies By Testing Protocol Utilized, Matias D. Campos, Paola C. Zucchi, Ann Phung, Steven N. Leonard, Elizabeth B. Hirsch

Pharmacy Faculty Scholarship

Background: Contaminated hospital surfaces are an important source of nosocomial infections. A major obstacle in marketing antimicrobial surfaces is a lack of efficacy data based on standardized testing protocols. Aim: We compared the efficacy of multiple testing protocols against several “antimicrobial” film surfaces.

Methods: Four clinical isolates were used: one Escherichia coli, one Klebsiella pneumoniae, and two Staphylococcus aureus strains. Two industry methods (modified ISO 22196 and ASTM E2149), a “dried droplet”, and a “transfer” method were tested against two commercially available antimicrobial films, one film in development, an untreated control, and a positive (silver) control film. At 2 (only ...


Needle In The Haystack: Combining Intravital Imaging And Mathematical Modeling To Understand How Vaccine-Induced T Cells Find Malaria-Infected Cells In Murine Livers, Vitaly V. Ganusov, Ian Cockburn, Reka Kelemen May 2016

Needle In The Haystack: Combining Intravital Imaging And Mathematical Modeling To Understand How Vaccine-Induced T Cells Find Malaria-Infected Cells In Murine Livers, Vitaly V. Ganusov, Ian Cockburn, Reka Kelemen

Biology and Medicine Through Mathematics Conference

No abstract provided.


A Novel And Rapid Staphylococcus Aureus Bacterial Identification Method Utilizing Immunomagnetic Beads And Single Cell Laser-Light Scattering, Kaylagh Hollen May 2016

A Novel And Rapid Staphylococcus Aureus Bacterial Identification Method Utilizing Immunomagnetic Beads And Single Cell Laser-Light Scattering, Kaylagh Hollen

All NMU Master's Theses

Staphylococcus aureus is the most commonly isolated human associated bacterial pathogen. It plays an important role in skin and soft-tissue infections, pneumonia, endocarditis, osteomyelitis, foreign-body infections, and sepsis. S. aureus diagnosis and treatment requires a minimum of 24-48. With this in mind, previous studies suggest that faster pathogen identification has been linked to improved patient outcomes. Improved patient outcomes including a reduction in hospitalization time, decreased risk of nosocomial infections, and decreased in medical costs. The impact of faster identification on patient outcome has led us to develop an alternative method of S. aureus identification via ImmunoMagnetic Separation (IMS) and ...


Metagenomic Sequencing With Strain-Level Resolution Implicates Uropathogenic E. Coli In Necrotizing Enterocolitis And Mortality In Preterm Infants, Doyle V. Ward, Matthias Scholz, Moreno Zolfo, Diana H. Taft, Kurt R. Schibler, Adrian Tett, Nicola Segata, Ardythe L. Morrow Mar 2016

Metagenomic Sequencing With Strain-Level Resolution Implicates Uropathogenic E. Coli In Necrotizing Enterocolitis And Mortality In Preterm Infants, Doyle V. Ward, Matthias Scholz, Moreno Zolfo, Diana H. Taft, Kurt R. Schibler, Adrian Tett, Nicola Segata, Ardythe L. Morrow

Open Access Articles

Necrotizing enterocolitis (NEC) afflicts approximately 10% of extremely preterm infants with high fatality. Inappropriate bacterial colonization with Enterobacteriaceae is implicated, but no specific pathogen has been identified. We identify uropathogenic E. coli (UPEC) colonization as a significant risk factor for the development of NEC and subsequent mortality. We describe a large-scale deep shotgun metagenomic sequence analysis of the early intestinal microbiome of 144 preterm and 22 term infants. Using a pan-genomic approach to functionally subtype the E. coli, we identify genes associated with NEC and mortality that indicate colonization by UPEC. Metagenomic multilocus sequence typing analysis further defined NEC-associated strains ...


Antibiotic Efficacy And Interaction In Escherichia Coli During Varying Nutrient Conditions, Kristina K. Millar Jan 2016

Antibiotic Efficacy And Interaction In Escherichia Coli During Varying Nutrient Conditions, Kristina K. Millar

Scripps Senior Theses

Due to the recent rise in antibiotic resistant pathogens, and the difficulties surrounding the quest for new antibiotics, many researchers have started revisiting antibiotic interactions in hopes of finding new treatment options. The primary outcome of this project was to examine the efficacy of concomitant antibiotic use under varying nutrient conditions, to identify variations in antibiotic interactions. Antibiotic interactions were studied, utilizing E. coli as a model bacterial system, grown in four different media types. E. coli cultures were treated with streptomycin, tobramycin, erythromycin, and amikacin individually and in a pairwise fashion at varying doses. We found that at least ...


Design And Testing Of Novel Anthrax Vaccines Utilizing A Tobacco Mosaic Virus Expression System, Ryan C. Mccomb Dec 2015

Design And Testing Of Novel Anthrax Vaccines Utilizing A Tobacco Mosaic Virus Expression System, Ryan C. Mccomb

KGI Theses and Dissertations

Anthrax is a potentially fatal disease caused by the bacteria Bacillus anthracis. Infection and disease occur after spores gain entry into the body, germinate into vegetative bacteria, and produce toxin. Bacillus anthracis spores have been engineered as bioweapons and have been used repeatedly in warfare and terrorism to inflict casualties in military and civilian populations. Currently, only one vaccine has been approved for prevention of anthrax in the United States. This vaccine is an undefined product that is difficult to produce, requires a long vaccination schedule, and is reactogenic. Efforts to make an improved anthrax vaccine are being pursued. With ...


Virulence Of Group A Streptococci Is Enhanced By Human Complement Inhibitors, David Ermert, Jutamas Shaughnessy, Thorsten Joeris, Jakub Kaplan, Catherine J. Pang, Evelyn A. Kurt-Jones, Peter A. Rice, Sanjay Ram, Anna M. Blom Jul 2015

Virulence Of Group A Streptococci Is Enhanced By Human Complement Inhibitors, David Ermert, Jutamas Shaughnessy, Thorsten Joeris, Jakub Kaplan, Catherine J. Pang, Evelyn A. Kurt-Jones, Peter A. Rice, Sanjay Ram, Anna M. Blom

Open Access Articles

Streptococcus pyogenes, also known as Group A Streptococcus (GAS), is an important human bacterial pathogen that can cause invasive infections. Once it colonizes its exclusively human host, GAS needs to surmount numerous innate immune defense mechanisms, including opsonization by complement and consequent phagocytosis. Several strains of GAS bind to human-specific complement inhibitors, C4b-binding protein (C4BP) and/or Factor H (FH), to curtail complement C3 (a critical opsonin) deposition. This results in diminished activation of phagocytes and clearance of GAS that may lead to the host being unable to limit the infection. Herein we describe the course of GAS infection in ...


Tonb Not Directly Related To Efflux Of Antibiotics In E. Coli, Amber Gombash May 2015

Tonb Not Directly Related To Efflux Of Antibiotics In E. Coli, Amber Gombash

Honors Projects

Studies in Pseudomonas aeruginosa have suggested that the TonB energy transduction system directly contributes to efflux-mediated antibiotic resistance, ostensibly by energizing one or more efflux systems. We have found ∆tonB strains of Escherichia coli to similarly be more sensitive to certain antibiotics relative to wild-type strains. To test the hypothesis that this enhanced sensitivity involved the energization of efflux systems, sensitivity patterns for a variety of antibiotics were evaluated using a set of strains differentially lacking genes encoding the Acr efflux system, the universal outer membrane efflux portal TolC, and TonB. No correlation was evident between the resistance phenotypes of ...


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

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 ...


Listeria Monocytogenes Can Utilize Both M Cell Transcytosis And Inla-Mediated Uptake To Cross The Epithelial Barrier Of The Intestine During An Oral Infection Model Of Listeriosis, Hilary Denney Jan 2014

Listeria Monocytogenes Can Utilize Both M Cell Transcytosis And Inla-Mediated Uptake To Cross The Epithelial Barrier Of The Intestine During An Oral Infection Model Of Listeriosis, Hilary Denney

Theses and Dissertations--Medical Sciences

The invasive pathways, InlA- and InB-mediated uptake and M cell transcytosis, that Listeria monocytogenes uses to invade the intestine have mainly been studied using infection models that do not truly replicate what occurs during a natural infection. Recently, our lab has developed an oral infection model that is more physiolocally relevant to what occurs during food borne listeriosis. We have sought to evaluate the relative roles of the previously defined invasive pathways, in our oral model of infection. We have done this by utilizing an InlAmCG Lm strain that is able to bind murine E-cadherin, knockout Lm strains, ΔinlA Lm ...


Mycological Study For A Management Plan Of A Neotropical Show Cave (Brazil), Erika Linzi Silva Taylor, Maria Aparecida De Resende Stoianoff, Rodrigo Lopes Ferreira Oct 2013

Mycological Study For A Management Plan Of A Neotropical Show Cave (Brazil), Erika Linzi Silva Taylor, Maria Aparecida De Resende Stoianoff, Rodrigo Lopes Ferreira

International Journal of Speleology

Caves are stable environments with characteristics favoring the development of microorganisms. The allocthonous input of organic matter and microbes into the warm Neotropical caves may favor the development of filamentous fungi, including pathogenic species. Histoplasma capsulatum is a pathogenic species commonly found in caves and associated with bat and bird guano. Many Brazilian caves have been historically visited due to scenic and religious tourism. The objective of this study was to perform a microbiology study for a management plan of a show cave in Brazil, focusing on the presence and distribution of pathogenic and opportunistic fungi in the cave. Statistics ...


Food, Pathogen, Signal: The Multifaceted Nature Of A Bacterial Diet, Lesley T. Macneil, Albertha J. M. Walhout Oct 2013

Food, Pathogen, Signal: The Multifaceted Nature Of A Bacterial Diet, Lesley T. Macneil, Albertha J. M. Walhout

Program in Systems Biology Publications and Presentations

C. elegans, both in the wild and in the lab, live on a diet of live bacteria. The bacterial diet provides nutrients for C. elegans, but can also play a number of other roles in C. elegans physiology. Recently, we compared the effects of different bacterial diets on life history traits and gene expression. Here, we discuss our recent findings in the context of other dietary studies and highlight challenges in understanding dietary effects. For instance, since bacteria can be pathogenic it can be difficult to disentangle pathogenic from dietary effects. Here we summarize different bacterial diets used for C ...


Proteomic Studies Of The Influenza Virus-Human Cell Interactions: The Responses Of Host Cell Protein Expression To Viral Infection And The Novel Host Proteins That Interact With Virus Protein Ns1, Yimeng Wang May 2013

Proteomic Studies Of The Influenza Virus-Human Cell Interactions: The Responses Of Host Cell Protein Expression To Viral Infection And The Novel Host Proteins That Interact With Virus Protein Ns1, Yimeng Wang

Theses and Dissertations

Influenza A viruses (IAVs) continue to be a threat to human health. Despite extensive studies, the mechanisms underlying the IAVs-host interactions during IAV infection remain elusive. We employed quantitative proteomic methods to systematically explore the host cell protein expression responses to IAV infection and examine the function of a critical IAV protein called NS1 by identifying its host binding partners. Specifically, we used a 2-dimentional gel electrophoresis (2-DE) based proteomic method to screen host proteins whose expression was substantially altered by IAV. One critical protein named IκB kinase-gamma (IKKγ) was found to be significantly down-regulated during IAV infection. Functional studies ...


An Investigation Of The Subtype Diversity Of Clinical Isolates Of Irish Clostridium Difficile Ribotypes 027 And 078 By Repetitive-Extragenic Palindromic Pcr, Denise Drudy, K. Solomon, S. Murray, L. Scott, S. Mcdermott,, A. Martin, C. O’Donoghue, M. Skally, K. Burns, L. Fenelon, F. Fitzpatrick,, L. Kyne, S. Fanning Jan 2011

An Investigation Of The Subtype Diversity Of Clinical Isolates Of Irish Clostridium Difficile Ribotypes 027 And 078 By Repetitive-Extragenic Palindromic Pcr, Denise Drudy, K. Solomon, S. Murray, L. Scott, S. Mcdermott,, A. Martin, C. O’Donoghue, M. Skally, K. Burns, L. Fenelon, F. Fitzpatrick,, L. Kyne, S. Fanning

Articles

A repetitive-extragenic palindromic PCR (rep-PCR) subtyping method (DiversiLab) in conjunction with ribotyping, toxinotyping and antimicrobial-susceptibility testing was used to detect subtypes within Clostridium difficile ribotypes 027 and 078. Clinical isolates of ribotypes 027 (toxinotype III) (n530) and 078 (toxinotype V) (n523) were provided by health-care facilities across the Republic of Ireland over 2 months in 2006 and 1 month in 2009. Ribotype 027 isolates were significantly more related to each other (9 different subtype profiles) when compared to ribotype 078 isolates (14 different profiles) (P50.001; cut-off .90 % similarity). Almost half of ribotype 078 isolates (45.5 %) showed no relationship ...


An Evaluation Of Methicillin Resistant Staphylococcus Aureus Survival On Five Environmental Surfaces Under Two Different Humidities, With And Without The Addition Of Bovine Serum Albumin, Courtney Ann Coughenour May 2009

An Evaluation Of Methicillin Resistant Staphylococcus Aureus Survival On Five Environmental Surfaces Under Two Different Humidities, With And Without The Addition Of Bovine Serum Albumin, Courtney Ann Coughenour

UNLV Theses, Dissertations, Professional Papers, and Capstones

The spread of antibiotic resistant bacteria is a major public health concern, as they result in greater healthcare costs and increased morbidity and mortality rates. Methicillin resistant Staphylococcus aureus (MRSA) is one organism of particular concern, with the number of infections increasing in epidemic proportion. Bacterial surface contamination with MRSA is significant, as it may serve as a reservoir for transmission and have negative health implications. The purpose of this study was to evaluate survival of MRSA on five environmental surface materials; glass, wood, vinyl, plastic, and cloth. The effect of relative humidity (RH) and bovine serum albumin (BSA) were ...