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

Medical Microbiology Commons

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

Diseases

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1 - 30 of 251

Full-Text Articles in Medical Microbiology

Typhlitis In A Neutropenic Patient, Alice He Bs, Wern Lynn Ng Md, Lay She Ng Md, Si Yuan Khor Md, Chandi Garg Md Apr 2024

Typhlitis In A Neutropenic Patient, Alice He Bs, Wern Lynn Ng Md, Lay She Ng Md, Si Yuan Khor Md, Chandi Garg Md

Tower Health Research Day

No abstract provided.


Rare Case Of Mycobacterium Avium Complex Peritonitis In A Patient With Multiple Myeloma Undergoing Peritoneal Dialysis, Sacide S. Ozgur, Nida Ansari, Dhruv Patel, Ryan Rahman, Raymond Shih Jan 2024

Rare Case Of Mycobacterium Avium Complex Peritonitis In A Patient With Multiple Myeloma Undergoing Peritoneal Dialysis, Sacide S. Ozgur, Nida Ansari, Dhruv Patel, Ryan Rahman, Raymond Shih

Journal of Community Hospital Internal Medicine Perspectives

Mycobacterium avium complex (MAC) infections can present as a variety of severe diseases. While it has a predilection for immunocompromised patients such as those with Human immunodeficiency virus (HIV), it can also affect immunocompetent patients as well. One of the rare yet severe diseases that MAC infections can present is MAC peritonitis. Often hard to distinguish from other causes of peritonitis, high clinical suspicion should be maintained for those who are susceptible. Here we present an 85-year-old female with a past medical history of end-stage renal disease on peritoneal dialysis who presented with nausea and vomiting. She was found to …


The Implications Of Ferroptosis In Antibiotic Resistance, Marysol Hohl Nov 2023

The Implications Of Ferroptosis In Antibiotic Resistance, Marysol Hohl

Senior Honors Theses

Bacterial infections in the United States are becoming increasingly resistant to existing antibiotic treatments. Due to projected increases in resistance and the recent decrease in novel antibacterials, experts have determined that the United States is in the “post-antibiotic era.” The scientific community has failed to resolve resistance despite the continual discovery of new antibiotic compounds. In the past decade, a novel form of cell death called ferroptosis has been implicated in antibiotic treatment by employing the use of nanotechnology. This literature review will describe the problem of bacterial resistance and demonstrate how current research is pioneering a new age of …


Tumor-Resident Lactobacillus Iners Confer Chemoradiation Resistance Through Lactate-Induced Metabolic Rewiring, Lauren E. Colbert, Molly B. El Alam, Rui Wang, Tatiana Karpinets, David Lo, Erica J. Lynn, Timothy A. Harris, Jacob H. Elnaggar, Kyoko Yoshida-Court, Katarina Tomasic, Julianna K. Bronk, Julie Sammouri, Ananta V. Yanamandra, Adilene V. Olvera, Lily G. Carlin, Travis Sims, Andrea Y. Delgado Medrano, Tatiana Cisneros Napravnik, Madison O'Hara, Daniel Lin, Chike O. Abana, Hannah X. Li, Patricia J. Eifel, Anuja Jhingran, Melissa Joyner, Lilie Lin, Lois M. Ramondetta, Andrew M. Futreal Oct 2023

Tumor-Resident Lactobacillus Iners Confer Chemoradiation Resistance Through Lactate-Induced Metabolic Rewiring, Lauren E. Colbert, Molly B. El Alam, Rui Wang, Tatiana Karpinets, David Lo, Erica J. Lynn, Timothy A. Harris, Jacob H. Elnaggar, Kyoko Yoshida-Court, Katarina Tomasic, Julianna K. Bronk, Julie Sammouri, Ananta V. Yanamandra, Adilene V. Olvera, Lily G. Carlin, Travis Sims, Andrea Y. Delgado Medrano, Tatiana Cisneros Napravnik, Madison O'Hara, Daniel Lin, Chike O. Abana, Hannah X. Li, Patricia J. Eifel, Anuja Jhingran, Melissa Joyner, Lilie Lin, Lois M. Ramondetta, Andrew M. Futreal

School of Medicine Faculty Publications

Tumor microbiota can produce active metabolites that affect cancer and immune cell signaling, metabolism, and proliferation. Here, we explore tumor and gut microbiome features that affect chemoradiation response in patients with cervical cancer using a combined approach of deep microbiome sequencing, targeted bacterial culture, and in vitro assays. We identify that an obligate L-lactate-producing lactic acid bacterium found in tumors, Lactobacillus iners, is associated with decreased survival in patients, induces chemotherapy and radiation resistance in cervical cancer cells, and leads to metabolic rewiring, or alterations in multiple metabolic pathways, in tumors. Genomically similar L-lactate-producing lactic acid bacteria commensal to other …


Rare Case Of Prosthetic Joint Infection Caused By Salmonella Enterica - A Case Report, Carlos Ramos, Shyama Appareddy, Peter J. Gonzalez Oct 2023

Rare Case Of Prosthetic Joint Infection Caused By Salmonella Enterica - A Case Report, Carlos Ramos, Shyama Appareddy, Peter J. Gonzalez

Research Colloquium

Introduction: Collectively, over 1 million total knee arthroplasties (TKA) and total hip arthroplasties (THA) are performed in the United States each year. In 2010 it was estimated that 1.58% of the United States general population has received a TKA. Prosthetic joint infections (PJI) are the most common indication for a TKA revision1 . In total, S. aureus is responsible for about 50% of all prosthetic joint infections, and about 15% are caused by gram negative pathogens2 .

Objective: This is a case report which describes the presentation and clinical course of a 59-yearold female with Salmonella enterica septic arthritis of …


Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado Oct 2023

Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado

Research Colloquium

Background: Catheter-associated urinary tract infections (CA-UTIs) account for 40 percent of nosocomial infections worldwide. Their elimination is at the forefront of quality improvement in one South Texas acute care hospital.

Methods: Over a period of 6 months, five CA-UTIs occurred in one South Texas acute care hospital. These cases were identified via regular surveillance by Infection Prevention staff and the Laboratory Department of the hospital. This research reviews patient age, sex, length of stay, bacteria contracted, appropriate antibiotic use, patient characteristics, and overall outcomes.

Results: Between the months of July and December 2021, 5 CAUTIs were contracted. Patients ranged in …


A Novel Gardnerella, Prevotella, And Lactobacillus Standard That Improves Accuracy In Quantifying Bacterial Burden In Vaginal Microbial Communities, Jacob H. Elnaggar, Caleb M. Ardizzone, Nuno Cerca, Evelyn Toh, Paweł Łaniewski, Rebecca A. Lillis, Melissa M. Herbst-Kralovetz, Alison J. Quayle, Christina A. Muzny, Christopher M. Taylor Jun 2023

A Novel Gardnerella, Prevotella, And Lactobacillus Standard That Improves Accuracy In Quantifying Bacterial Burden In Vaginal Microbial Communities, Jacob H. Elnaggar, Caleb M. Ardizzone, Nuno Cerca, Evelyn Toh, Paweł Łaniewski, Rebecca A. Lillis, Melissa M. Herbst-Kralovetz, Alison J. Quayle, Christina A. Muzny, Christopher M. Taylor

School of Graduate Studies Faculty Publications

Bacterial vaginosis (BV) is the most common vaginal dysbiosis. In this condition, a polymicrobial biofilm develops on vaginal epithelial cells. Accurately quantifying the bacterial burden of the BV biofilm is necessary to further our understanding of BV pathogenesis. Historically, the standard for calculating total bacterial burden of the BV biofilm has been based on quantifying Escherichia coli 16S rRNA gene copy number. However, E. coli is improper for measuring the bacterial burden of this unique micro-environment. Here, we propose a novel qPCR standard to quantify bacterial burden in vaginal microbial communities, from an optimal state to a mature BV biofilm. …


Relative And Quantitative Characterization Of The Bovine Bacterial Ocular Surface Microbiome In The Context Of Suspected Ocular Squamous Cell Carcinoma, Hannah B. Gafen, Chin-Chi Liu, Nikole E. Ineck, Clare M. Scully, Melanie A. Mironovich, Lauren Guarneri, Christopher M. Taylor, Meng Luo, Marina L. Leis, Erin M. Scott, Renee T. Carter, Andrew C. Lewin Jun 2023

Relative And Quantitative Characterization Of The Bovine Bacterial Ocular Surface Microbiome In The Context Of Suspected Ocular Squamous Cell Carcinoma, Hannah B. Gafen, Chin-Chi Liu, Nikole E. Ineck, Clare M. Scully, Melanie A. Mironovich, Lauren Guarneri, Christopher M. Taylor, Meng Luo, Marina L. Leis, Erin M. Scott, Renee T. Carter, Andrew C. Lewin

School of Medicine Faculty Publications

The ocular surface microbiome is altered in certain disease states. The aim of this study was to characterize the bovine bacterial ocular surface microbiome (BBOSM) in the context of ocular squamous cell carcinoma (OSCC). The conjunctiva of normal (n = 28) and OSCC (n = 10) eyes of cows aged 2 to 13 years from two farms in Louisiana and Wyoming were sampled using individual sterile swabs. DNA extraction followed by 16S ribosomal ribonucleic acid (rRNA) gene sequencing and real-time polymerase chain reaction (RT-PCR) were performed to, respectively, assess the relative and absolute BBOSM. Discriminant analysis (DA) was performed using …


Stewardship Opportunities For Cervical Lymphadenitis And Deep Neck Space Abscesses, Aaron Shaw, Brian R. Lee, Lauren Kazmaier, Emily Baker, Tina Dao, Sandra Arnold, Angela Myers May 2023

Stewardship Opportunities For Cervical Lymphadenitis And Deep Neck Space Abscesses, Aaron Shaw, Brian R. Lee, Lauren Kazmaier, Emily Baker, Tina Dao, Sandra Arnold, Angela Myers

Research Days

Background: Cervical lymphadenitis (LAD) and deep neck space abscesses (DNSA) are common pediatric infections caused by similar bacteria. We sought to determine differences in presentation, diagnosis, and treatment between LAD and DNSA to identify antimicrobial and diagnostic stewardship opportunities.

Methods: Charts were obtained using ICD9/10 codes for retropharyngeal and parapharyngeal abscessed (DNSA), and LAD between 1/1/10-12/31/20 from two pediatric centers. 1981 charts were identified. Charts were excluded if the diagnosis was not a bacterial infection (e.g. Kawasaki disease), if the LAD was not in the neck, or if caused by less common bacteria (e.g. tuberculosis). Data on presenting signs, symptoms, …


Oxidative Stress And Micrornas In Endothelial Cells Under Metabolic Disorders, Morgan Minjares, Wendy Wu, Jie-Mei Wang May 2023

Oxidative Stress And Micrornas In Endothelial Cells Under Metabolic Disorders, Morgan Minjares, Wendy Wu, Jie-Mei Wang

Pharmaceutical Sciences Faculty Publications

Reactive oxygen species (ROS) are radical oxygen intermediates that serve as important second messengers in signal transduction. However, when the accumulation of these molecules exceeds the buffering capacity of antioxidant enzymes, oxidative stress and endothelial cell (EC) dysfunction occur. EC dysfunction shifts the vascular system into a pro-coagulative, proinflammatory state, thereby increasing the risk of developing cardiovascular (CV) diseases and metabolic disorders. Studies have turned to the investigation of microRNA treatment for CV risk factors, as these post-transcription regulators are known to co-regulate ROS. In this review, we will discuss ROS pathways and generation, normal endothelial cell physiology and ROS-induced …


Elucidating The Impact Of Sos-Response Timing In On Escherichia Coli Survival Following Treatment With Fluoroquinolone Topoisomerase Inhibitors, Stephanie Schofield May 2023

Elucidating The Impact Of Sos-Response Timing In On Escherichia Coli Survival Following Treatment With Fluoroquinolone Topoisomerase Inhibitors, Stephanie Schofield

Honors Scholar Theses

Antibiotic treatment failure is a public health crisis, with a 2019 report stating that roughly 35,000 deaths occur in the United States yearly due to bacterial infections that are unresponsive to antibiotics (1). One complication in the treatment of bacterial infection is antibiotic persistence which further compromises our battle to effectively treat infection. Bacterial persisters can exist in clonal bacterial cultures and can tolerate antibiotic treatment by undergoing reversible phenotypic changes. They can survive drug concentrations that their genetically identical kin cannot. Some persisters remain in a slow growing state and are difficult to target with current antibiotics. A specific …


Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell May 2023

Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell

Poster Presentations

Honors research poster.

Haemaphysalis longicornis is a species of tick native to eastern Asia, including eastern China, Japan, eastern Russia, and Korea. To date, it has invaded and has now established its existence in Australia, New Zealand, and several of the Pacific Islands. This species of tick has recently been introduced to the United States, having a confirmed sighting in November 2017 on a sheep farm in New Jersey and since establishing populations in 18 states along the east coast and Appalachia. Based on the existing locations of H. longicornis in its native regions, as well as in the United …


Hpv-Related Anal Cancer Is Associated With Changes In The Anorectal Microbiome During Cancer Development, Jacob H. Elnaggar, Victoria O. Huynh, Daniel Lin, R. Tyler Hillman, Chike O. Abana, Molly B. El Alam, Katarina C. Tomasic, Tatiana V. Karpinets, Ramez Kouzy, Jae L. Phan, Jennifer Wargo, Emma B. Holliday, Prajnan Das, Melissa P. Mezzari, Nadim J. Ajami, Erica J. Lynn, Bruce D. Minsky, Van K. Morris, Andrea Milbourne, Craig A. Messick, Ann H. Klopp, P. Andrew Futreal, Cullen M. Taniguchi, Kathleen M. Schmeler, Lauren E. Colbert Mar 2023

Hpv-Related Anal Cancer Is Associated With Changes In The Anorectal Microbiome During Cancer Development, Jacob H. Elnaggar, Victoria O. Huynh, Daniel Lin, R. Tyler Hillman, Chike O. Abana, Molly B. El Alam, Katarina C. Tomasic, Tatiana V. Karpinets, Ramez Kouzy, Jae L. Phan, Jennifer Wargo, Emma B. Holliday, Prajnan Das, Melissa P. Mezzari, Nadim J. Ajami, Erica J. Lynn, Bruce D. Minsky, Van K. Morris, Andrea Milbourne, Craig A. Messick, Ann H. Klopp, P. Andrew Futreal, Cullen M. Taniguchi, Kathleen M. Schmeler, Lauren E. Colbert

School of Graduate Studies Faculty Publications

Background: Squamous cell carcinoma of the anus (SCCA) is a rare gastrointestinal cancer. Factors associated with progression of HPV infection to anal dysplasia and cancer are unclear and screening guidelines and approaches for anal dysplasia are less clear than for cervical dysplasia. One potential contributing factor is the anorectal microbiome. In this study, we aimed to identify differences in anal microbiome composition in the settings of HPV infection, anal dysplasia, and anal cancer in this rare disease. Methods: Patients were enrolled in two prospective studies. Patients with anal dysplasia were part of a cross-sectional cohort that enrolled women with high-grade …


Topical Anesthetic Gel Interferes With Antibacterial Efficacy Of Povidone-Iodine Both In Vitro And In Vivo, Cecilly Kelleher Bs, Jacob Im Md, Linda Kang Bs, Aleksey Mishulin Md, Sukhvinder Singh Phd, Ashok Kumar Phd Mar 2023

Topical Anesthetic Gel Interferes With Antibacterial Efficacy Of Povidone-Iodine Both In Vitro And In Vivo, Cecilly Kelleher Bs, Jacob Im Md, Linda Kang Bs, Aleksey Mishulin Md, Sukhvinder Singh Phd, Ashok Kumar Phd

Medical Student Research Symposium

Purpose: To evaluate the effects of viscous lidocaine gel on the antimicrobial efficacy of povidone-iodine (PI) and their order of application in both in vitro and in vivo models.

Methods: In vitro antibacterial effects were tested against Staphylococcus aureus (S. aureus) with disc diffusion methods for application of lidocaine alone, PI alone, PI before lidocaine, and lidocaine before PI. Zones of inhibition were measured after incubation at 37°C overnight. Mouse eyes were colonized with S. aureus for in vivo study to which PI and/or lidocaine were applied in various combinations. Eyes were then rinsed with saline, and …


Chlamydia Trachomatis Subverts Alpha-Actinins To Stabilize Its Inclusion, A. Haines, J. Wesolowski, F. Paumet Jan 2023

Chlamydia Trachomatis Subverts Alpha-Actinins To Stabilize Its Inclusion, A. Haines, J. Wesolowski, F. Paumet

Department of Microbiology and Immunology Faculty Papers

Chlamydia trachomatis is the leading cause of sexually transmitted bacterial disease and a global health burden. As an obligate intracellular pathogen, Chlamydia has evolved many strategies to manipulate its host and establish its intracellular niche called the inclusion. C. trachomatis reorganizes the host actin cytoskeleton to form scaffolds around the inclusion and reinforce the growing inclusion membrane. To control the kinetics and formation of actin scaffolds, Chlamydia expresses the effector InaC/CT813, which activates the host GTPase RhoA. Here, we have discovered that InaC stabilizes actin scaffolds through the host actin cross-linking proteins α-actinins 1 and 4. We demonstrate that α-actinins …


A Rodent Model For Dirofilaria Immitis, Canine Heartworm: Parasite Growth, Development, And Drug Sensitivity In Nsg Mice, Jessica A. Hess, Mark L. Eberhard, Marcelo Segura-Lepe, Kathrin Grundner-Culemann, Barbara Kracher, Jeffrey Shryock, John Harrington, David Abraham Jan 2023

A Rodent Model For Dirofilaria Immitis, Canine Heartworm: Parasite Growth, Development, And Drug Sensitivity In Nsg Mice, Jessica A. Hess, Mark L. Eberhard, Marcelo Segura-Lepe, Kathrin Grundner-Culemann, Barbara Kracher, Jeffrey Shryock, John Harrington, David Abraham

Department of Microbiology and Immunology Faculty Papers

Heartworm disease, caused by Dirofilaria immitis, remains a significant threat to canines and felines. The development of parasites resistant to macrocyclic lactones (ML) has created a significant challenge to the control of the infection. The goal of this study was to determine if mice lacking a functional immune response would be susceptible to D. immitis. Immunodeficient NSG mice were susceptible to the infection, sustaining parasites for at least 15 weeks, with infective third-stage larvae molting and developing into the late fourth-stage larvae. Proteomic analysis of host responses to the infection revealed a complex pattern of changes after infection, with at …


Combatting Bacterial Infections: The Efficacy Of Poly-Gamma-Glutamic Acid On The Prevention Of Nasopharyngeal Infections Among Individuals With Cleft Lip And Palate, Florence Pun Jan 2023

Combatting Bacterial Infections: The Efficacy Of Poly-Gamma-Glutamic Acid On The Prevention Of Nasopharyngeal Infections Among Individuals With Cleft Lip And Palate, Florence Pun

Scripps Senior Theses

Cleft lip and palate (CLP) is a medical condition where children are born with an unfused lip and palate. While surgery is required to fuse the lip and palate, there are other conditions that children with CLP face after surgeries, such as otitis media (OM), speech impediments, and difficulty breathing. Particularly, OM occurs frequently in individuals with CLP because the tensor veli palatini muscles cannot open the Eustachian tube frequently and ventilate the middle ear properly, even after surgery. This thesis is a research proposal to evaluate whether γ-PGA can be used in nasal washes to safely prevent nasopharyngeal infections …


Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh Jan 2023

Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh

Undergraduate Research Posters

Human Immunodeficiency Virus (HIV) is a retrovirus that infects CD4+ T cell lymphocytes in humans, leading to the development of Acquired Immunodeficiency Syndrome (AIDS) if left untreated. While current treatment methods, including antiretroviral combination treatments, effectively limit HIV replication, HIV can evade these treatments due to its high mutation rate. Long-term antiretroviral treatment can also be toxic to patients, meaning patients would benefit from a new mechanism of HIV treatment. RNA interference (RNAi) is an antiviral pathway found in mammals, plants, and insects that involves a small-interfering RNA that is incorporated into a protein complex called the RNA-induced Silencing Complex …


Covid-19 Vaccine Effectiveness In Preventing Severe Infections And Mortality Among Patients In Kerala, India., Surag Mk, Sarin S. M, Sarosh Kumar K K, Udaya A Jan 2023

Covid-19 Vaccine Effectiveness In Preventing Severe Infections And Mortality Among Patients In Kerala, India., Surag Mk, Sarin S. M, Sarosh Kumar K K, Udaya A

Digital Journal of Clinical Medicine

ABSTRACT

Background:

India has a top status among world countries, related to the COVID-19 mortality that had crossed the 3-lakh level. The second wave of COVID19 had ravaged the world countries, created havoc of the highest order, leaving many hapless, thanks to the low availability of oxygen, ICU facilities, vaccines and counselling prospects.

There is a lack of information about how COVID-19 vaccines have affected mortality in specific geographic areas.

Method:

A Retrospective record-based design. Patients were matched for age, sex, ethnicity, co-morbidities and grouped into fully immunized, partially immunized and non-immunized.

The primary outcome was in-hospital deaths and secondary …


Follow-Up Blood Cultures In Gram-Negative Bacteremia: How Do They Impact Outcomes?, Azza Elamin, Faisal Khan, Rajasekhar Jagarlamudi Nov 2022

Follow-Up Blood Cultures In Gram-Negative Bacteremia: How Do They Impact Outcomes?, Azza Elamin, Faisal Khan, Rajasekhar Jagarlamudi

Journal of Community Hospital Internal Medicine Perspectives

Introduction: Several studies have questioned the utility of obtaining follow-up blood cultures in Gram-negative bacteremia, but the impact of this practice on clinical outcomes is not fully understood. Methods: A retrospective cohort study of adult patients admitted with Gram-negative bacteremia over a two year period, to compare outcomes in those with and without follow-up blood cultures obtained. Data collected included demographics, comorbidities and presumed source of bacteremia. White blood cell count and presence of fever or hemodynamic compromise on the day of follow-up blood culture were recorded. The primary objective was to compare 30-day mortality between the two groups. Secondary …


Defining The Role Of Powassan Virus In Evading Host Antiviral Immunity (September 2022), Melissa Molho, Phd, Holly Ramage, Phd Sep 2022

Defining The Role Of Powassan Virus In Evading Host Antiviral Immunity (September 2022), Melissa Molho, Phd, Holly Ramage, Phd

Department of Microbiology and Immunology Posters

Background

Powassan Virus (POWV) is an emerging neurotropic flavivirus transmitted to humans through the bite of an infected tick. Currently, there is no specific antiviral treatment nor approved vaccine for POWV. During infection, many interferon-independent host proteins and pathways sense and respond to viral infection. Flaviviruses have evolved multiple mechanisms to counteract host antiviral programs, often with individual viral proteins mediating this antagonism. However, it has not been determined if these mechanisms are conserved across diverse flaviviruses.


Infection And Transmission Determinants Of Flea-Borne Rickettsioses, Hanna J. Laukaitis Aug 2022

Infection And Transmission Determinants Of Flea-Borne Rickettsioses, Hanna J. Laukaitis

<strong> Theses and Dissertations </strong>

The genus Rickettsia is comprised of Gram-negative, obligate intracellular bacteria that are spread by hematophagous arthropods. Elucidating the factors conferring rickettsial virulence has perplexed investigators for decades, complicated by the lack of efficient genetic tools necessary to uncover rickettsial- and vector-specific factors contributing to persistence. The advent of transposon mutagenesis has enabled the field to make vast developments in uncovering novel rickettsial mechanisms utilized in various host backgrounds. Thus, the aim of this study was to generate Rickettsia felis transposon mutants and characterize novel phenotypes associated with genetic disruption in an arthropod background. Distribution of rickettsiae is reliant on the …


Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan Jul 2022

Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan

Mathematics, Physics, and Computer Science Faculty Articles and Research

n this study, we combined all-atom MD simulations, the ensemble-based mutational scanning of protein stability and binding, and perturbation-based network profiling of allosteric interactions in the SARS-CoV-2 spike complexes with a panel of cross-reactive and ultra-potent single antibodies (B1-182.1 and A23-58.1) as well as antibody combinations (A19-61.1/B1-182.1 and A19-46.1/B1-182.1). Using this approach, we quantify the local and global effects of mutations in the complexes, identify protein stability centers, characterize binding energy hotspots, and predict the allosteric control points of long-range interactions and communications. Conformational dynamics and distance fluctuation analysis revealed the antibody-specific signatures of protein stability and flexibility of the …


Effect Of Sub-Inhibitory Concentrations Of Nitrofurantoin, Ciprofloxacin And Trimethoprim On In-Vitro Biofilm Formation In Uropathogenic Escherichia Coli, Shane Whelan Jun 2022

Effect Of Sub-Inhibitory Concentrations Of Nitrofurantoin, Ciprofloxacin And Trimethoprim On In-Vitro Biofilm Formation In Uropathogenic Escherichia Coli, Shane Whelan

ORBioM (Open Research BioSciences Meeting)

The purpose of the current study was to determine the effect of sublethal concentrations of nitrofurantoin, ciprofloxacin and trimethoprim on biofilm formation in 57 uropathogenic Escherichia coli strains (UPEC).

The MIC of nitrofurantoin, ciprofloxacin and trimethoprim was determined for 57 UPEC isolates. Biofilm formation for each isolate with and without sub-lethal concentrations of each antibiotic was then quantified, and the statistical significance of changes in biofilm formation was ascertained by way of a Dunnett's test.

The effects of sub-MIC antibiotics on biofilm formation of UPEC were variable. A total of 22.8% of strains were induced to form biofilm by nitrofurantoin, …


The Role Of Coagulase-Negative Staphylococcal Secreted Products On Staphylococcus Aureus And Staphylococcus Lugdunensis Infections, Denny Chin Apr 2022

The Role Of Coagulase-Negative Staphylococcal Secreted Products On Staphylococcus Aureus And Staphylococcus Lugdunensis Infections, Denny Chin

Electronic Thesis and Dissertation Repository

The Staphylococcus genus is comprised of over 40 bacterial species. The most well-studied species in this genus is the notorious human pathogen Staphylococcus aureus, a bacterium that produces coagulase among many other virulence factors. Since S. aureus is a major health burden and causes a plethora of diseases in humans, it has received significant attention and much research has been done to understand its biology to treat diseases caused by this pathogen. However, the coagulase-negative staphylococci (CoNS) make up most of the staphylococcal species and have received less attention since they are thought to have a lesser impact on …


Cellular Dynamics And Disease Outcome Of Type 3 Streptococcus Pneumoniae Clinical Isolates Differ Between Strains, Taylor Rae Plunkett White Apr 2022

Cellular Dynamics And Disease Outcome Of Type 3 Streptococcus Pneumoniae Clinical Isolates Differ Between Strains, Taylor Rae Plunkett White

Theses and Dissertations (ETD)

Streptococcus pneumoniae is a bacterial pathogen that continues to be a major cause of disease around the world. It is not only the number one cause of bacterial pneumonia but also the cause of about 15% of the deaths of children under 5 around the world. There is a lot of research done on this organism, but with around 100 known serotypes and each one producing a unique capsule, there is still much more to be studied. The Etiology of Pneumonia in the Community (EPIC) study conducted by the CDC observed the burden of hospitalizations caused by pneumonia while determining …


A Quantitative Analysis Of The Efficacy Of Various Essential Oils Against The Sars Cov-2 Virus, Elizabeth Wagstaff, Chandrelyn Kraczek, Jack Brandon Lopez Mar 2022

A Quantitative Analysis Of The Efficacy Of Various Essential Oils Against The Sars Cov-2 Virus, Elizabeth Wagstaff, Chandrelyn Kraczek, Jack Brandon Lopez

Annual Research Symposium

A poster presentation and abstract for the Roseman Symposium. The project focuses on testing 3 essential oil blends and two disinfectants containing an essential oil blend against SARS CoV-2 in response to the COVID-19 pandemic. The project procedure involves plaque assays, disinfection, and neutralization techniques.


Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado Feb 2022

Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado

MEDI 9331 Scholarly Activities Clinical Years

Background: Catheter-associated urinary tract infections (CA-UTIs) account for 40 percent of nosocomial infections worldwide. Their elimination is at the forefront of quality improvement in one South Texas acute care hospital.

Methods: Over a period of 6 months, five CA-UTIs occurred in one South Texas acute care hospital. These cases were identified via regular surveillance by Infection Prevention staff and the Laboratory Department of the hospital. This research reviews patient age, sex, length of stay, bacteria contracted, appropriate antibiotic use, patient characteristics, and overall outcomes.

Results: Between the months of July and December 2021, 5 CAUTIs were contracted. Patients …


Effects Of Gaba On Inflammation And Intestinal Barrier Disruption, Tyrel W. Long Jan 2022

Effects Of Gaba On Inflammation And Intestinal Barrier Disruption, Tyrel W. Long

EWU Masters Thesis Collection

Gut dysbiosis and intestinal barrier disruption have been linked to multiple sclerosis (MS). Our previous works show that experimental autoimmune encephalomyelitis (EAE) induction modifies the gut's microbiota composition, reducing frequencies of gamma-aminobutyric acid (GABA)-producing bacteria. GABA levels are reduced in the brains and circulation of MS patients. We engineered Lactococcus lactis with extra copies of gadB (glutamic acid decarboxylase) and gadC (glutamate/GABA antiporter) to increase GABA levels produced by the bacterium (GAD-L. lactis). EAE studies showed that the treatment with GAD-L. lactis and not with a L. lactis control expressing an empty plasmid (P-L. lactis) reduced the severity of the …


Evaluation Of Stratified Antibiograms For Use In Laboratory And Antimicrobial Stewardship, Linsey Donner Dec 2021

Evaluation Of Stratified Antibiograms For Use In Laboratory And Antimicrobial Stewardship, Linsey Donner

Theses & Dissertations

Antibiograms are critical for choosing empiric antimicrobial therapy. Cumulative antibiograms, which aggregate susceptibility data, can mask differences within specific patient subsets or clinical syndromes. This dissertation was done to determine if antibiotic susceptibilities showed substantial differences when comparing stratified antibiograms to cumulative antibiograms.

Antibiotic susceptibility data was retrospectively obtained from Nebraska Medicine January 1, 2017 – December 31, 2019 for Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis. The University of Nebraska Medical Center’s web antibiogram clinical decision support tool was used to export the data. Bacteria-antibiotic susceptibility rates of stratified antibiograms …