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Full-Text Articles in Bacteria

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

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

Honors Theses

Haemaphysalis longicornis ticks are invasive to the United States with potential to transmit several tick-borne pathogens that are native to the United States. Based on existing locations of H. longicornis in its native regions in Asia, as well as its invasive populations that are established in the United States, several geographic range prediction models have been produced to help understand future range expansion and distribution of this invasive tick in North America. Unfortunately, these models do not all agree and there is uncertainty associated with the potential geographic range expansion of H. longicornis ticks in North America. Climate can affect …


Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris May 2023

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

All Dissertations

Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …


Independent Effects Of Hiv And Antiretroviral Therapy On The Oral Microbiome Identified By Multivariate Analyses, Clifford J. Beall, Elizabeth A. Lilly, Carolina Granada, Kelly Treas, Kenneth R. Dubois, Shahr B. Hashmi, Jose A. Vazquez, Michael E. Hagensee, Ann L. Griffen, Eugene J. Leys, Paul L. Fidel Apr 2023

Independent Effects Of Hiv And Antiretroviral Therapy On The Oral Microbiome Identified By Multivariate Analyses, Clifford J. Beall, Elizabeth A. Lilly, Carolina Granada, Kelly Treas, Kenneth R. Dubois, Shahr B. Hashmi, Jose A. Vazquez, Michael E. Hagensee, Ann L. Griffen, Eugene J. Leys, Paul L. Fidel

School of Dentistry Faculty Publications

The oral microbiome is an important predictor of health and disease. We recently reported significant yet modest effects of HIV under highly active antiretroviral therapy (ART) on the oral microbiome (bacterial and fungal) in a large cohort of HIV-positive (HIV+) and matched HIV-negative (HIV-) individuals. As it was unclear whether ART added to or masked further effects of HIV on the oral microbiome, the present study aimed to analyze the effects of HIV and ART independently, which also included HIV- subjects on preexposure prophylaxis (PrEP) therapy. Cross-sectional analyses of the effect of HIV devoid of ART (HIV+ ART- versus matched …


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 …


Development Of A Chemical Biology Approach To Uncover The Influence Of Sequence Variations On Ces1 Activity In Live Cells, Samuel James Knebel Jan 2023

Development Of A Chemical Biology Approach To Uncover The Influence Of Sequence Variations On Ces1 Activity In Live Cells, Samuel James Knebel

Masters Theses

Drug metabolism is the biochemical process of modifying drugs to detoxify and remove them through enzymatic transformations. These biotransformation’s occur primarily in the liver and are critical to understanding how pharmaceutical compounds are chemically altered inside the human body. Human carboxylesterases (CESs) catalyze the hydrolysis of esters, amides, thioesters, and carbamates. CES-mediated hydrolysis plays an important role in the metabolism of many drugs including the first FDA approved antiviral treatment for COVID-19, remdesivir (Veklury), the seizure control medication rufinamide (Banzel), and the flu antiviral drug oseltamivir (Tamiflu). CES activity is known to be influenced by a variety of factors including …


Sea-Phages Research Opportunity, Sarah Ballarin Oct 2022

Sea-Phages Research Opportunity, Sarah Ballarin

Trick to the Treat of Internships and Research

Research opportunity targeted for freshmen and sophomores through the SEA-PHAGES program. The goal of the research is to discover new bacteriophages (viruses that infect bacteria) to help combat antibiotic resistance. Phage therapy is a promising alternative to conventional antibiotics. Phages have also been widely used in the food industry to prevent microbial growth on certain foods and are currently being explored as a method for bioremediation of oil spills and wastewater treatment.

Last year, my research team discovered two new bacteriophages: Genamy16 and NovaSharks that were able to infect the bacteria Gordonia rubripertincta. These phages can possibly be used for …


Tracking The Source Of Helicobacter Pylori In Watersheds Of San Juan, Puerto Rico, Mary Elizabeth Sailors Jul 2022

Tracking The Source Of Helicobacter Pylori In Watersheds Of San Juan, Puerto Rico, Mary Elizabeth Sailors

Biology Theses

Helicobacter pylori is a pathogenic bacterium that infects more than half of the world’s population. The large number of H. pylori infections in Puerto Rico could be related to the waterborne transmission of the pathogen. While the San Juan Bay Estuary (SJBE) system is home to over three million people, water quality studies in this area of Puerto Rico are lacking. The goal of this study is to determine seasonal and yearly (2020-2021) shifts and relationships between the presence of H. pylori and host-specific (human and dog) Bacteroides in streams that flow through the northern coastal zone of Puerto Rico …


A Case Report Of Pulmonary Actinomycosis: A Diagnostic Quagmire, Sarah Akbani, Aderinsola O. Ademiluyi, Jonathan Dean, Vinita Mathur May 2022

A Case Report Of Pulmonary Actinomycosis: A Diagnostic Quagmire, Sarah Akbani, Aderinsola O. Ademiluyi, Jonathan Dean, Vinita Mathur

Advances in Clinical Medical Research and Healthcare Delivery

The implications of misdiagnosis can be drastic, especially when the correct diagnosis is treatable. Pulmonary actinomycosis is one of the complications of infection with actinomyces, an anaerobic gram-positive organism that is usually found as a part of the normal flora in the human body infection. It is a very rare disease and is frequently mistaken with other diagnoses owing to its nonspecific presentation. In this report, we present a 67-year-old male with a mass like lesion on a CT scan of his chest that was done due to progressively worsening productive cough, weight loss and fatigue. These symptoms could have …


Safety And Efficacy Of Silver-Coated Biomaterials In Vivo, Megan Klem, Darien L. Seidman, Rahyan Mahmoud, Manuella Adu, Lei Yu, Jeffrey Hettinger, Renee M Demarest May 2022

Safety And Efficacy Of Silver-Coated Biomaterials In Vivo, Megan Klem, Darien L. Seidman, Rahyan Mahmoud, Manuella Adu, Lei Yu, Jeffrey Hettinger, Renee M Demarest

Rowan-Virtua Research Day

Overtreatment and overuse of antibiotics in healthcare and agricultural settings have contributed to the selective pressure on bacterial strains to develop resistance. Resistance can develop as a result of mutations and subsequent resistance genes that allow bacteria to survive against antibiotics. Novel silver-oxide coatings were developed and were previously demonstrated to prevent adhesion of gram-negative bacteria (Escherichia Coli and Pseudomonas Aeruginosa) to the disc, but did not prevent gram-positive bacterial adherence (Streptococcus Aureus). In order to determine whether the silver-oxide coatings are bacterial static and may be preventing progression to biofilm formation, in vivo analysis of S. Aureus attached to …


Neurosyphilis: A Monkey Among Men, Cameron Rowe Do, Nathan Buckley Do, Bhaskar Chhetri Md, Suresh Paudel Md May 2022

Neurosyphilis: A Monkey Among Men, Cameron Rowe Do, Nathan Buckley Do, Bhaskar Chhetri Md, Suresh Paudel Md

Journal of Community Hospital Internal Medicine Perspectives

Neurosyphilis is the progression of the untreated sexually transmitted infection caused by Treponema pallidum. When the initial infection is not adequately treated, progression of primary syphilis can lead to a wide variety of serious health sequelae. While neurosyphilis can appear up to 10-30 years after the initial infection, syphilis can invade the nervous system at any stage of infection and can imitate symptoms of many other diseases. This variety of symptoms is why syphilis has been called “The Great Pretender” or “The monkey among diseases” (12). This is a case report of an 83-year-old female with a history of multiple …


Identification Of Ciprofloxacin Resistance Factors Via In Vivo Evolution Of Aeromonas Veronii In The Medicinal Leech, Lauren Daddi May 2022

Identification Of Ciprofloxacin Resistance Factors Via In Vivo Evolution Of Aeromonas Veronii In The Medicinal Leech, Lauren Daddi

Honors Scholar Theses

Infections from ciprofloxacin (Cp) resistant (CpR) Aeromonas veronii have been reported in increasing numbers among patients receiving leech therapy in recent years. Mutations in DNA gyrase, gyrA S83I, and DNA topoisomerase IV, parC E91K, along with acquisition of the qnrS2 gene located on the pAv42 plasmid, have been identified as genetic factors contributing to CpR in A. veronii. A strain of A. veronii harboring all known resistance factors was previously constructed and has a Cp minimum inhibitory concentration (MIC) of 3 µg/ml, which remains below the resistance threshold of 4 µg/ml and well below the high …


Investigating Alternative Induction Of The S. Aureus 80a Prophage, Jody Caretti Apr 2022

Investigating Alternative Induction Of The S. Aureus 80a Prophage, Jody Caretti

Student Scholar Showcase

Widespread antibiotic resistance has quickly become one of the most concerning crises affecting modern medicine, especially in cases of Staphylococcal infections, which have become resistant to all ��-lactam antibiotics. As a result, research into alternative forms of treatment for bacterial infections is a top priority. Bacteriophage therapy is a popular candidate for replacing antibiotics, due to the way the viruses interact with the bacteria. The 80�� prophage integrates its DNA into Staphylococcus aureus strain 10616 via the lysogenic cycle, and replicates with the bacterial cell. When stressed, the bacteria stop replicating and the prophage stimulates the lytic cycle, activating transcription …


Urinary Incontinence: Understanding The Silent Plight Of Women, Yasmin Nadeem Parpio, Anmol Minaz, Sonia Ijaz Haider Apr 2022

Urinary Incontinence: Understanding The Silent Plight Of Women, Yasmin Nadeem Parpio, Anmol Minaz, Sonia Ijaz Haider

School of Nursing & Midwifery

Urinary incontinence (UI) is defined as the complaint of involuntary loss of urine. UI affects both men and women but is more common in women. It has been identified as a World Health Organization priority. The burden related to UI at local, national, and global levels is huge and its impact in terms of physical, social, mental, and financial aspects makes it a concerning issue. However, there exist several barriers in terms of knowledge and attitude in seeking healthcare among women experiencing UI. This calls upon a multi-disciplinary approach involving professionals from different disciplines and tackling it with collaborative and …


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 …


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

Graduate Theses/Dissertations

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 …


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 …


Eradication Of Enterococcus Faecalis In Conventional Endodontic Retreatments (A Randomized Clinical Trial), Fadl H. Khaled, Roula S. Abiad, Khaled Abd El Galil, Essam Osman Nov 2021

Eradication Of Enterococcus Faecalis In Conventional Endodontic Retreatments (A Randomized Clinical Trial), Fadl H. Khaled, Roula S. Abiad, Khaled Abd El Galil, Essam Osman

BAU Journal - Creative Sustainable Development

Enterococcus faecalis is the most common bacteria isolated in conventional endodontic retreatments. Aim: To compare the impact of three irrigation modalities on the elimination of the isolated microbial strains of Enterococcus faecalis. Materials and Methods: Thirty patients requiring conventional endodontic retreatment for one of their mandibular premolars and tested positive for E. faecalis were chosen. Patients were randomly divided into three groups (n=10) according to the irrigation modality to be used; group I: syringe irrigation (NaOCl 2.625%), group II: NaOCl 2.625%+EndoActivator and group III: NaOCl 2.625%+diode laser. Before obturation, samples S2 were collected and PCR analysis was performed to identify …


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 …


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: Master of Public Health

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. …


A Novel Application Of Galleria Mellonella Larvae To Study Pathogenesis Of Rickettsia Rickettsii Infection, Jacob M. Jones Apr 2021

A Novel Application Of Galleria Mellonella Larvae To Study Pathogenesis Of Rickettsia Rickettsii Infection, Jacob M. Jones

Honors College Theses

Rickettsia are obligate intracellular tick-borne bacteria that cause acute undifferentiated febrile illness accompanied by headache, malaise, myalgias, and disseminated endothelial infection. Immune responses to Rickettsia and pathogenesis of rickettsioses are not fully understood. Current work with Rickettsia is limited to vertebrate models that are strictly regulated and have low throughput. Since the innate immune system of vertebrates retains striking similarities with the immune response in insects, invertebrates are being used to study host responses to various pathogens. The purpose of this study was to evaluate if larvae of the greater wax moth Galleria mellonella (GML) can be used as an …


3d Printing Of Human Microbiome Constituents To Understand Spatial Relationships And Shape Parameters In Bacteriology, Jacques Izard, Teklu Kuru Gerbaba, Shara R. P. Yumul Mar 2021

3d Printing Of Human Microbiome Constituents To Understand Spatial Relationships And Shape Parameters In Bacteriology, Jacques Izard, Teklu Kuru Gerbaba, Shara R. P. Yumul

Department of Food Science and Technology: Faculty Publications

Effective laboratory and classroom demonstration of microbiome size and shape, diversity, and ecological relationships is hampered by a lack of high-resolution, easy-to-use, readily accessible physical or digital models for use in teaching. Three-dimensional (3D) representations are, overall, more effective in communicating visuospatial information, allowing for a better understanding of concepts not directly observable with the unaided eye. Published morphology descriptions and microscopy images were used as the basis for designing 3D digital models, scaled at 20,000×, using computer-aided design software (CAD) and generating printed models of bacteria on mass-market 3D printers. Sixteen models are presented, including rod-shaped, spiral, flask-like, vibroid, …


When The Pandemic Opts For The Lockdown: Secretion System Evolution In The Cholera Bacterium, Francis J. Santoriello, Stefan Pukatzki Feb 2021

When The Pandemic Opts For The Lockdown: Secretion System Evolution In The Cholera Bacterium, Francis J. Santoriello, Stefan Pukatzki

Publications and Research

Vibrio cholerae, the causative agent of the diarrheal disease cholera, is a microbe capable of inhabiting two different ecosystems: chitinous surfaces in brackish, estuarine waters and the epithelial lining of the human gastrointestinal tract. V. cholerae defends against competitive microorganisms with a contact-dependent, contractile killing machine called the type VI secretion system (T6SS) in each of these niches. The T6SS resembles an inverted T4 bacteriophage tail and is used to deliver toxic effector proteins into neighboring cells. Pandemic strains of V. cholerae encode a unique set of T6SS effector proteins, which may play a role in pathogenesis or pandemic …


Streptococcus Cristatus – An Oral Bacterium Causing A Case Of Mild Bacteremia And “Possible Endocarditis”, Camilo Guzman, Adi Zaclli, John Molinari Jan 2021

Streptococcus Cristatus – An Oral Bacterium Causing A Case Of Mild Bacteremia And “Possible Endocarditis”, Camilo Guzman, Adi Zaclli, John Molinari

Medical Student Research Symposium

Streptococcus cristatus is a member of the Mitis streptococcus group. Like other members of this group, it resides in mucosal surfaces of the oral cavity but rarely causes disease. We present a case of S. cristatus bacteremia and “possible endocarditis” (per the modified Duke criteria) in a 59-year-old male suffering from end- stage cryptogenic cirrhosis. To date, it is the fifth reported case of disease caused by the microbe, and the first adult case in which S. cristatus was the sole microbe identified. Our patient had a history of dental caries and poor dentition, which were likely the source of …


Comparisons Of Oral, Intestinal, And Pancreatic Bacterial Microbiomes In Patients With Pancreatic Cancer And Other Gastrointestinal Diseases, Mei Chung, Naisi Zhao, Richard Meier, Devin C. Koestler, Guojun Wu, Erika De Castillo, Bruce J. Paster, Kevin Charpentier, Jacques Izard, Karl T. Kelsey, Dominique S. Michaud Jan 2021

Comparisons Of Oral, Intestinal, And Pancreatic Bacterial Microbiomes In Patients With Pancreatic Cancer And Other Gastrointestinal Diseases, Mei Chung, Naisi Zhao, Richard Meier, Devin C. Koestler, Guojun Wu, Erika De Castillo, Bruce J. Paster, Kevin Charpentier, Jacques Izard, Karl T. Kelsey, Dominique S. Michaud

Department of Food Science and Technology: Faculty Publications

Background: Oral microbiota is believed to play important roles in systemic diseases, including cancer. Methods: We collected oral samples (tongue, buccal, supragingival, and saliva) and pancreatic tissue or intestinal samples from 52 subjects, and characterized 16S rRNA genes using high-throughput DNA sequencing.

Results: Bray–Curtis plot showed clear separations between bacterial communities in the oral cavity and those in intestinal and pancreatic tissue samples. PERMANOVA tests indicated that bacterial communities from buccal samples were similar to supragingival and saliva samples, and pancreatic duct samples were similar to pancreatic tumor samples, but all other samples were significantly different from each …


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 (ETD)

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 …


Investigating Microbial And Host Factors That Modulate Severity Of Clostridioides Difficile Associated Disease, Armando Lerma Nov 2020

Investigating Microbial And Host Factors That Modulate Severity Of Clostridioides Difficile Associated Disease, Armando Lerma

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Clostridioides difficile is recognized as one of the most important pathogens in hospital and community healthcare settings. The clinical outcome of infection of toxigenic C. difficile infection (CDI) ranges from asymptomatic colonization to fulminant pseudomembranous colitis and death. In recent studies, it has been suggested that a high proportion of nosocomial CDI cases are transmitted from asymptomatic carriers which might be acting as infection reservoirs. Understanding what causes the different responses to infection could lead to the development of novel prevention and treatment strategies. Although several explanations have been proposed to explain variations in susceptibility, understanding of the exact mechanisms …


The Inhibitory Effects Of An Antimicrobial Gel On The Staphylococcus Species, Mara Trinkle Aug 2020

The Inhibitory Effects Of An Antimicrobial Gel On The Staphylococcus Species, Mara Trinkle

Undergraduate Honors Theses

The prevalence of antibiotic resistant bacteria has made the choices for topical treatments for patients who experience burns wounds extremely limited. The Staphylococcus genus is naturally occurring in and on the human body but can become harmful once it enters the bloodstream. A novel antimicrobial gel has been shown by our laboratory to inhibit both the planktonic growth and biofilm formation of Staphylococcus aureus in previous studies. The antimicrobial gel is made of seven natural compounds including antioxidants (vitamin C and E). We wanted to examine the effects of the antimicrobial gel on numerous other Staphylococcal species because it is …


Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding Aug 2020

Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding

Electronic Theses and Dissertations

Despite efforts to decrease the global health burden of malaria, infections with Plasmodium species continue to cause over 200 million episodes of malaria each year which resulted in 405,000 deaths in 2018 [1]. One complication of malaria is increased susceptibility to invasive bacterial infections. Plasmodium infections impair host immunity to non-Typhoid Salmonella (NTS) through activities of heme oxygenase I (HO-I) )-induced release of immature granulocytes and myeloid cell-derived IL-10. Yet, it is not known if these mechanisms are specific to NTS. We show here, that Plasmodium yoelii 17XNL (Py) infected mice had impaired clearance of systemic Listeria monocytogenes (Lm) during …


Identifying Determinants Of Target Specificity In Two Related Bacterial Peptide Toxins, Andrew D. Holmes May 2020

Identifying Determinants Of Target Specificity In Two Related Bacterial Peptide Toxins, Andrew D. Holmes

Honors Thesis

Toxin-antitoxin (TA) systems were originally identified as two-component systems ensuring the stable inheritance of plasmids in bacterial populations. Recently, they have been identified on bacterial chromosomes where their functions remain mostly undefined. The par locus of E. faecalis plasmid pAD1 (parpAD1) was the first TA system defined in a Gram-positive bacterium and a homolog encoded on the E. faecalis chromosome (parEF0409) was later described. Related loci numbering in the hundreds have been identified throughout Gram-positive bacteria based on homology to the toxin of the system, Fst, and similarities in genetic organization and regulation. Despite …


Biological Sex Influences Susceptibility To Acinetobacter Baumannii Pneumonia In Mice, Sílvia Pires, Adeline Peignier, Jeremy Seto, Davida S. Smyth, Dane Parker Apr 2020

Biological Sex Influences Susceptibility To Acinetobacter Baumannii Pneumonia In Mice, Sílvia Pires, Adeline Peignier, Jeremy Seto, Davida S. Smyth, Dane Parker

Publications and Research

Acinetobacter baumannii (A. baumannii) is an extremely versatile multidrug-resistant pathogen with a very high mortality rate; therefore, it has become crucial to understand the host response during its infection. Given the importance of mice for modeling infection and their role in preclinical drug development, equal emphasis should be placed on the use of both sexes. Through our studies using a murine model of acute pneumonia with A. baumannii, we observed that female mice were more susceptible to infection. Likewise, treatment of male mice with estradiol increased their susceptibility to infection. Analysis of the airway compartment revealed enhanced inflammation and reduced …