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Full-Text Articles in Organisms

Comparison Of The Humoral Immune Response Following Both Bacterial Challenge And Rnai Of Major Factors On Proliferation Of Bartonella Quintana In The Human Louse, Jake Zina Oct 2022

Comparison Of The Humoral Immune Response Following Both Bacterial Challenge And Rnai Of Major Factors On Proliferation Of Bartonella Quintana In The Human Louse, Jake Zina

Masters Theses

Human body lice, Pediculus humanus humanus, and head lice, Pediculus humanus capitis, have been hematophagous ectoparasites of humans for thousands of years. Despite being ecotypes, only body lice are known to transmit bacterial diseases to humans, and it appears that lower humoral and cellular immune responses allow body lice to possess a higher vector competence. We previously observed that the transcription level of the defensin 1 gene was up-regulated only in head lice following oral challenge of Bartonella quintana, a causative agent of trench fever, and also that body lice excreted more viable B. quintana in their …


Regulation Of Mhc Ii Trafficking And Expression By Host And Viral Factors, Alex Lac Jul 2022

Regulation Of Mhc Ii Trafficking And Expression By Host And Viral Factors, Alex Lac

Electronic Thesis and Dissertation Repository

Antigen presentation by major histocompatibility complex class II (MHC II) to the adaptive immune system is crucial for mounting sterilizing immune responses. This central role has made antigen presentation a target for antagonism by many pathogens. Notably, infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) decrease MHC II expression in several immune cells. The mechanisms responsible for this suppression are unknown but involves either redirecting MHC II molecules away from the cell surface or inhibiting MHC II expression. To understand how pathogens manipulate intracellular MHC II trafficking, we first investigated the role of the Golgi trafficking regulator, ERC1, in …


How Environmental Change Will Impact Mosquito-Borne Diseases, Arsal Khan May 2022

How Environmental Change Will Impact Mosquito-Borne Diseases, Arsal Khan

Master's Projects and Capstones

Mosquitos, the most lethal species throughout human history, are the most prevalent source of vector-borne diseases and therefore a major global health burden. Mosquito-borne disease incidence is expected to shift with environmental change. These changes can be predicted using species distribution models. With the wide variety of methods used for models, consensus for improving accuracy and comparability is needed. A comparative analysis of three recent modeling approaches revealed that integrating modeling techniques compensates for trade-offs associated with a singular approach. An area that represents a critical gap in our ability to predict mosquito behavior in response to changing climate factors, …


Flippase Inhibitors As Antimicrobial Agents, Robert Tancer May 2022

Flippase Inhibitors As Antimicrobial Agents, Robert Tancer

Seton Hall University Dissertations and Theses (ETDs)

Drug resistant microbes are a considerable challenge for modern medicine to overcome. The research described in this dissertation involved development of lipid flippase inhibitors and investigating their potential as antimicrobial agents against various drug resistant microbes. The microbes primarily investigated were methicillin resistant Staphylococcus aureus (MRSA) & Cryptococcus neoformans. Chapter 1 reviews the historical perspective and summarizes the current state of the field of research. In Chapter 2, the design space of an antimicrobial peptide known as humimycin was explored and the effects of modifications on its structure were observed against MRSA. Several key observations resulted. Most notably, the …


Quantifying The Degree Of Programmed Cell Death In The Central Nervous System Among Different Genotypes Of The Drosophila Melanogaster, Radha Awasthi May 2022

Quantifying The Degree Of Programmed Cell Death In The Central Nervous System Among Different Genotypes Of The Drosophila Melanogaster, Radha Awasthi

Chancellor’s Honors Program Projects

No abstract provided.


Investigation On Bacterial Signaling Through Generation Of A Ppgpp Biosensor, Andrew Robinson May 2022

Investigation On Bacterial Signaling Through Generation Of A Ppgpp Biosensor, Andrew Robinson

Undergraduate Honors Theses

Guanosine tetraphosphate (ppGpp) is a bacterial signaling molecule involved in activating the stringent response, a cellular reaction to environmental stress that downregulates cell division and metabolism processes to conserve nutrients. The stringent response is implicated in some instances of antibiotic persistence, so broadening the current understanding of ppGpp signaling is useful. This thesis seeks to generate a ppGpp biosensor that will bind ppGpp and emit fluorescent light in its presence, which will allow for improved research into the pathways and functions of the signaling molecule. To generate a novel ppGpp biosensor, I converted a biosensor previously used to detect cyclic …


Bacteriophages: Paving The Road For The Future Of Medicine, Luke Brinkerhoff May 2022

Bacteriophages: Paving The Road For The Future Of Medicine, Luke Brinkerhoff

Honors Theses

Bacteriophages are a possible solution to antibiotic resistance, which is predicted to be detrimental world-wide by the year 2050. Personal field research was also conducted for a project studying the characteristics of two bacteriophages on a single bacterial host.


Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan May 2022

Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan

Electronic Theses and Dissertations

Retinal fibrosis is detrimental to vision. Retinal pigment epithelial (RPE) cells contribute to several retinal fibrotic diseases. Upon exposure to TGF-β, a key fibrotic cytokine, RPE cells trans-differentiate to myofibroblasts marked by the integration of α-SMA fibers into F-actin stress fibers, which confer strong contractility. Myofibroblasts produce and contract the collagen-rich fibrotic scar and disrupt retinal architecture. In this study, we investigated the in vitro effects of the putative endocannabinoid compound N-oleoyl dopamine (OLDA) on TGF-β2 induced porcine RPE cell contraction and α-SMA expression. Using an in vitro collagen matrix contraction assay, we found that OLDA inhibited TGF-β2 induced contraction …


Diversity Of Bacteriophage In Burkholderia Species, Abigail Price Apr 2022

Diversity Of Bacteriophage In Burkholderia Species, Abigail Price

Honors Projects

Bacteriophages are viruses that infect and replicate within bacteria and offer the potential of a therapeutic alternative to chronic infections that do not respond to antibiotic-based therapies. B. vietnamiensis is one of a number of Burkholderia species involved with chronic drug resistant infections in the lungs of individuals with compromised respiratory systems, as found in those with chronic obstructive pulmonary disease and, most especially, are of particular significance in patients with cystic fibrosis. The diversity of the Burkholderia species is explored by using online databases and looking at bacteriophage or phage-encoding viruses found in B. vietnamiensis. The open reading frames …


Increasing Staff Compliance With Routine Hcv Screening And Improving Linkage To Care Among Patients Testing Hepatitis C Positive In The Emergency Department, Carson G. Swartz Jan 2022

Increasing Staff Compliance With Routine Hcv Screening And Improving Linkage To Care Among Patients Testing Hepatitis C Positive In The Emergency Department, Carson G. Swartz

DNP Projects

Background: Hepatitis C virus (HCV) is a blood-borne pathogen that can cause severe liver disease, cancer, and death and is a significant source of morbidity and mortality in the United States. Several academic medical centers including University of Kentucky Healthcare have implemented routine HCV screening for patients presenting to the emergency department (ED) and have discovered a large viral burden amongst patients who are often symptomatic.

Purpose: The purpose of this doctoral project is to increase staff compliance, confidence, and education regarding the HCV screening process in an urban, Level I emergency department, as well as to evaluate whether an …


The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth Jan 2022

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth

Williams Honors College, Honors Research Projects

It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H2O2 was the experimental factor to further test FeRB tolerance. H2O2 is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H2O2 concentrations were fed …


Implementing Educational Initiatives To Decrease Contamination And Costs In The Blood Culture Specimen Collection Process, Hannah M. Mcguire Jan 2022

Implementing Educational Initiatives To Decrease Contamination And Costs In The Blood Culture Specimen Collection Process, Hannah M. Mcguire

Master's Theses and Capstones

Background: The diagnosis of sepsis in a patient presenting with symptoms includes the collection of blood cultures which identifies the presence of specific infectious agents. The culture result will identify the organism as well as report sensitivity to various antimicrobial agents to allow the healthcare provider to determine the specific set of treatments, specifically antibiotics, that will be included in the medication regimen in combating the infection. When blood specimens become contaminated in the collection process, it hinders the success of rapidly treating these patients as repeat cultures will likely need to be completed for accurate treatment. This becomes a …


Effectiveness Of Stabilized Hypochlorous Acid In Acute Peritonitis Treatment: A Murine Surgical Study, Benjamin Michael Pomeroy Jan 2022

Effectiveness Of Stabilized Hypochlorous Acid In Acute Peritonitis Treatment: A Murine Surgical Study, Benjamin Michael Pomeroy

MSU Graduate Theses

Peritonitis is an inflammatory condition affecting the mesothelial cells that line the peritoneal cavity and is commonly induced by bowel perforations. This medical emergency is treated through antibiotic therapy and surgical intervention followed by tissue irrigation (lavage). Acute treatments aim to remove the bacterial burden, however recurring peritoneal infections occur at high rates and contribute to patient morbidity. These recurring infections are likely due to the inability of lavage solutions to remove the entire massive intra-abdominal bacterial load due to intestinal perforation. Numerous antiseptic solutions and antibiotic additives have been evaluated in their ability to improve source control by abdominal …


An Antimicrobial Polydopamine Surface Coating To Reduce Biofouling On Telemetry Tags Used In Marine Conservation Practices, Ariana Smies Jan 2022

An Antimicrobial Polydopamine Surface Coating To Reduce Biofouling On Telemetry Tags Used In Marine Conservation Practices, Ariana Smies

Dissertations, Master's Theses and Master's Reports

Satellite telemetry tags are used to track the migration patterns of large cetaceans. These tags penetrate the dermis and remain embedded in the underlying blubber tissue. As the dermis of cetaceans is host to a diverse microbiome, and it is impossible to clean the skin before implanting the devices, the potential for infection is increased when the tags penetrate through the skin. H2O2 is a potential antimicrobial agent that, in addition to showing broad-spectrum efficacy against gram-negative and gram-positive bacteria, can promote wound healing outcomes by promoting proliferative factors and peptides that protect against oxidative stress. However, …


Genital Chlamydia Infection Is Influenced By The Female Sex Hormones Estrogen And Progesterone In Vivo, Amy Gail Gravitte Dec 2021

Genital Chlamydia Infection Is Influenced By The Female Sex Hormones Estrogen And Progesterone In Vivo, Amy Gail Gravitte

Electronic Theses and Dissertations

Chlamydia is the most common bacterial sexually transmitted infection in the United States and worldwide. It often goes unnoticed due to lack of symptoms and left untreated it can ascend the female genital tract to cause sequelae like pelvic inflammatory disease and irreversible tubal infertility. In reproductive-aged women, female sex hormones estrogen (E2) and progesterone (P4) concentrations fluctuate during the menstrual cycle and are influenced by hormonal contraceptives and hormone replacement therapy. E2 and P4 influence genital Chlamydia infection in women and mice, but these multifactorial interactions are not entirely mapped out. The complex interplay of E2 and P4 with …


Investigating The Developmental Impacts Of 3,3’-Dichlorobiphenyl (Pcb-11) In Zebrafish (Danio Rerio), Monika A. Roy Oct 2021

Investigating The Developmental Impacts Of 3,3’-Dichlorobiphenyl (Pcb-11) In Zebrafish (Danio Rerio), Monika A. Roy

Doctoral Dissertations

The environmental pollutant 3,3’-dichlorobiphenyl (PCB-11) is a lower-chlorinated polychlorinated biphenyl (PCB) congener present in air and water samples. Both PCB-11 and its metabolite, 4-PCB-11-Sulfate, are detected in humans, including in pregnant women. The work conducted for this dissertation takes a developmental toxicology approach and uses zebrafish (Danio rerio) to investigate PCB-11’s potential impacts to the liver and pancreas. Chapter 1 introduces PCBs and the current knowledge gaps. Chapter 2 investigates PCB-11 interactions in short-term 4-day exposures with the Aryl hydrocarbon receptor (Ahr) pathway in both 0-20 mM individual and mixture exposures with other Ahr agonists. In Chapter 3, …


Disruption Of Insertion Sequence 200 (Is200) Leads To A Premature Induction Of The Cysteine Regulon In Salmonella Typhimurium, Naomi-Jean Q. Scherba Oct 2021

Disruption Of Insertion Sequence 200 (Is200) Leads To A Premature Induction Of The Cysteine Regulon In Salmonella Typhimurium, Naomi-Jean Q. Scherba

Electronic Thesis and Dissertation Repository

Salmonella Typhimurium is a leading contributor to non-typhoid diseases with complex regulatory networks that are key to understanding its pathogenicity and virulence. I explore the role of the sRNA IS200, where its deletion in Salmonellaleads to premature induction of the Cys regulon. The premature induction in ∆IS200 was validated through qRT-PCR and GFP transcriptional fusions and occurs at late exponential to early stationary phase. In addition, ∆IS200 leads to increased sensitivity to oxidative stress. The focus of this work has been to understand how ∆IS200 leads to premature Cys regulon induction, and I present three models: the futile import/export, …


Assesment Of Antibiotic Resistant Gene Expression In Clinical Isolates Of Pseudomonas Aeruginosa, Dustin Esmond Sep 2021

Assesment Of Antibiotic Resistant Gene Expression In Clinical Isolates Of Pseudomonas Aeruginosa, Dustin Esmond

Biology Theses

Increasing prevalence of nosocomial infections by antimicrobial resistant pathogens resulting in higher mortality rates and financial burden is of great concern. Pseudomonas aeruginosa represents one of six highly virulent “ESKAPE” pathogens that exhibit considerable intrinsic drug resistance as well as mechanisms for acquiring further resistance. As many of these mechanisms are regulated through gene expression, we sought to identify regulatory strategies and patterns at play in 23 clinical isolates collected from Baku, Azerbaijan and Tyler, Texas, USA. Real-time quantitative polymerase chain reaction was performed on six gene targets implicated in resistance and contrasted with antibiotic phenotypes. We found AmpC cephalosporinase …


Analysis Of Single Cell Rna-Seq Data Revealed Interferon Gamma Signaling Alteration In Severe Covid Patients, Ahmed Elbaz May 2021

Analysis Of Single Cell Rna-Seq Data Revealed Interferon Gamma Signaling Alteration In Severe Covid Patients, Ahmed Elbaz

Theses and Dissertations

Background: SARS-COV2 virus detected in December 2019, and was considered a pandemic in March 2020 by the WHO. Symptoms range from asymptomatic to life threatening ones. Studying cell-cell interactions in patients' blood samples may lead to novel diagnosis and treatment approaches.

Aim: This study aims to analyze single-cell RNA sequencing data to identify differences in cell-cell communications between healthy and COVID patients and differentially expressed T-cells genes that contributed to immune system antiviral activity.

Materials and methods: Single-Cell RNA sequencing data from seven COVID patients and five healthy individuals were collected from (GEO accession GSE155673). Cell types were identified and …


Hemin Utilization In Rhizobium Leguminosarum Atcc 14479, John Lusby May 2021

Hemin Utilization In Rhizobium Leguminosarum Atcc 14479, John Lusby

Electronic Theses and Dissertations

Rhizobium leguminosarum is a Gram negative, motile, nitrogen-fixing soil bacterium. Due to the scarcity of iron in the soil bacteria have developed a wide range of iron scavenging systems. The two types of iron scavenging systems used are indirect and direct. In-silico analysis of the genome identified a unique direct iron scavenging system the Hmu operon. This system has been identified in other closely related rhizobium species and is believed to be involved in utilizing heme compounds as a sole source of iron. We have attempted to characterize the role of the Hmu operon in iron utilization by monitoring the …


The Migration Of Carbapenem-Resistant Acinetobacter Baumannii From The Battlefields Of Iraq And Afghanistan To The Healthcare Facilities Of The Veterans Health Administration, Jeffery Rogers May 2021

The Migration Of Carbapenem-Resistant Acinetobacter Baumannii From The Battlefields Of Iraq And Afghanistan To The Healthcare Facilities Of The Veterans Health Administration, Jeffery Rogers

Capstone Experience

Multidrug-resistant organisms (MDRO) pose a great threat to health across the globe. That threat is also felt in the Veterans Health Administration (VHA). Wounded warriors returning home from the battlefields of Iraq and Afghanistan may have brought with them MDROs, such as the bacterium Acinetobacter baumannii, as they have transitioned from military service into the VHA facilities. This study investigates the interconnectedness of military service in the Department of Defense (DoD) and a lifetime of care at VHA through a longitudinal tracking of a linked cohort of combat veterans with battlefield injuries and subsequent MDR infections of A. baumannii. …


Identification And Characterization Of Butyrate-Producing Species In The Human Gut Microbiome, Grace Maline May 2021

Identification And Characterization Of Butyrate-Producing Species In The Human Gut Microbiome, Grace Maline

Theses/Capstones/Creative Projects

Inflammatory Bowel Diseases (IBD) including ulcerative colitis, indeterminate colitis, and Crohn’s disease are increasingly common conditions that places a high physical and financial burden on individuals and global healthcare systems. Though many treatments exist for these conditions, their unpredictable nature and causation make them difficult to manage across the variety of IBD patients. Additionally, many of these treatments come with undesirable side effects or modes of delivery. Therefore, it is worthwhile to explore the use of Short Chain Fatty Acids (SCFAs) such as butyrate whose affects in the human gut include decreased inflammation and decreased risk of colorectal cancer. As …


Novel Mammalian Models For Understanding And Treating Spinal Cord Injury, Michael B. Orr Jan 2021

Novel Mammalian Models For Understanding And Treating Spinal Cord Injury, Michael B. Orr

Theses and Dissertations--Physiology

Spinal cord injury (SCI) is devastating and often leaves the injured individual with persistent dysfunction. The injury persists because humans have poor wound repair and there are no pharmacologic treatments to induce wound repair after SCI. The continued efforts to discover therapeutic targets and develop treatments heavily relies on animal models. The purpose of this project is to develop and study novel mammalian models of SCI to provide insights for the development and effective implementation of SCI therapies.

Lab mice (Mus musculus) are a powerful tool for recapitulating the progression and persistent damage evident in human SCI, but …


Cellular Bioenergetics Regulates Cell Proliferation During Mammalian Regeneration, Sandeep Saxena Jan 2021

Cellular Bioenergetics Regulates Cell Proliferation During Mammalian Regeneration, Sandeep Saxena

Theses and Dissertations--Biology

Mammalian system consists of stress-sensing molecules that regulates their cellular response against damage, injury and oncogenic stress. During vertebrate regeneration, cells responding to injury re-enter the cell cycle and proliferate to form new tissue. Cell cycle re-entry or arrest is at least partly regulated by cellular senescence which negatively impacts the proliferative pool of cells during regeneration. What remains unclear is whether cells in regenerating systems possess an increased propensity to proliferate and are refractory to signals that induce senescence. My thesis work has focused on how fibroblasts from the ear pinna differentially regulate healing in highly regenerative mammals (e.g., …


Bacterial Association Networks From Healthy And Cancer-Associated Gut Microbiomes, Mark Loftus Jan 2021

Bacterial Association Networks From Healthy And Cancer-Associated Gut Microbiomes, Mark Loftus

Electronic Theses and Dissertations, 2020-

The human gastrointestinal tract is colonized by a diverse community of symbiotic microorganisms, mainly bacteria, that are known to play essential roles in maintaining the health of their human host. Disruption of this bacterial community has been associated with numerous diseases, including Colorectal Cancer (CRC). CRC is one of the leading causes of cancer-related deaths worldwide. As such, focus has been placed on the modulation of the bacterial community within the cancer-associated gut microbiome as the next step in possible CRC treatment and prevention strategies. To use the bacterial community for these purposes, a better understanding of the associations that …


Utilizing The Coughing Rat Model Of Pertussis To Improve Vaccine Efficacy, Jesse M. Hall Jan 2021

Utilizing The Coughing Rat Model Of Pertussis To Improve Vaccine Efficacy, Jesse M. Hall

Graduate Theses, Dissertations, and Problem Reports

Pertussis, also known as whooping cough, is a respiratory disease caused by the highly contagious, Gram-negative pathogen Bordetella pertussis (Bp). Infection occurs through inhalation of aerosolized droplets containing Bp, which then colonizes ciliated epithelial cells of the respiratory tract. Here, Bp expresses toxins and virulence factors that lead to leukocyte recruitment, paroxysmal cough, and impairment of host innate responses. Currently, in developed countries, acellular pertussis vaccines (aP; DTaP; Tdap) are used to prevent Bp infection and whooping cough disease. However, we currently realize that the aP vaccine efficacy quickly wanes resulting in a reemergence of pertussis. Recent …


Dendrimer-Based Antibiotics For The Treatment Of Bacterial Biofilm In Cystic Fibrosis (Cf), Younan Ma Jan 2021

Dendrimer-Based Antibiotics For The Treatment Of Bacterial Biofilm In Cystic Fibrosis (Cf), Younan Ma

Theses and Dissertations

Pseudomonas aeruginosa (PA) is the predominant pathogen in chronic lung infections of cystic fibrosis (CF) patients. The most important mechanism of adaptation of PA to host defense and antibiotic treatment is the formation of biofilms within the mucus layer covering the lung bronchi. The effectiveness of antibiotics such as aminoglycosides is significantly attenuated by their limited penetration through thick mucus and embedded biofilm matrix in patients’ lung. Inhaled tobramycin (Tobra), which is the most commonly used antibiotics in the treatment of PA infections for CF patients, is usually found to be in very high concentration in patients’ lung, and yet …


A Crisis Of Kelp, Rachel L. Sherman Dec 2020

A Crisis Of Kelp, Rachel L. Sherman

Capstones

Along with insects and lab-grown meat, for years seaweed has been lauded as a sustainable “food of the future” by the U.N. Food and Agricultural Organization. As the world increasingly turns to alternative foods in pursuit of a healthier Earth, seaweed has all the makings of an ecological savior. It’s plentiful — seaweeds and ocean algae make up roughly nine tenths of all the plant life on Earth — it’s cheap to harvest and get to market, packed with nutrition, and keeps oceans clean, absorbing more carbon dioxide and releasing more oxygen than the world’s rainforests.

But outside of Japanese …


Valley Fever: Education For Primary Care Providers And Allied Health Care Professionals, Michelle Elizabeth Bergen Dec 2020

Valley Fever: Education For Primary Care Providers And Allied Health Care Professionals, Michelle Elizabeth Bergen

Doctor of Nursing Practice (DNP) Projects

Valley Fever: Educating Primary Care Providers and Allied Healthcare Professionals

Abstract

Problem: Coccidioidomycosis (cocci), informally Valley Fever (VF), infects the lungs with the fungal spore coccidioides. It is prevalent in areas where soil disturbance occurs. Currently, there are no related educational or standardized guidelines exist for primary care providers (PCPs) in California’s Central Valley, where VF is highly endemic (Centers for Disease Control and Prevention, 2018).

Context: A Doctor of Nursing Practice project educational program for PCPs and allied healthcare workers (AHWs) at the Adventist Health Central Valley Network (AHCVN) clinics. The project aimed to educate PCPs to …


Site Tolerance Of The Rada Intein, Chase Taul, Christopher Lennon Dr Dec 2020

Site Tolerance Of The Rada Intein, Chase Taul, Christopher Lennon Dr

Honors College Theses

Inteins (intervening proteins) invade genes at the DNA level and splice out at the protein level. Once thought of as only a parasitic type of a mobile genetic element, recent work suggests a mutualistic relationship has formed in some cases within bacterial and archaeal hosts. After translation, a precursor protein is formed with the intein between two exteins. The intein is catalytic and can excise itself out through protein splicing. Intein insertion is biased towards the active site of the protein and is thought to cause inactivation of the host protein prior to splicing. Intein splicing is responsive to a …