Bacterial Infections and Mycoses Commons^™

Genomic Epidemiology Of Clostridium Difficile Colonization And Transmission In An Intensive Care Unit Cohort, Brianne Ciferri

Dissertations and Theses

Abstract

Genomic epidemiology of Clostridium difficile colonization and transmission in an intensive care unit cohort

by Brianne Ciferri, MPH

Advisor: C. Mary Schooling, PhD

Introduction: Clostridiodes difficile (C. difficile) is a leading cause of healthcare associated infections (HAI) in the United States and responsible for an estimated incidence of 223,900 cases and 12,800 deaths per year^1,2. C. difficile can cause gastrointestinal illness with symptoms ranging from mild diarrheal illness to a life-threatening condition. C. difficile is an opportunistic pathogen in which spores can live in an undisturbed dormant state within the intestinal tract and become …

Type Vi Secretion System Mutations Reduced Competitive Fitness Of Classical Vibrio Cholerae Biotype, Benjamin Kostiuk, Francis J. Santoriello, Laura Diaz-Satizabal, Fabiana Bisaro, Kyung-Jo Lee, Anna N. Dhody, Daniele Provenzano, Daniel Unterweger, Stefan Pukatzki

Publications and Research

The gram-negative bacterium Vibrio cholerae is the causative agent of the diarrhoeal disease cholera and is responsible for seven recorded pandemics. Several factors are postulated to have led to the decline of 6th pandemic classical strains and the rise of El Tor biotype V. cholerae, establishing the current 7th pandemic. We investigated the ability of classical V. cholerae of the 2nd and 6th pandemics to engage their type six secretion system (T6SS) in microbial competition against non-pandemic and 7th pandemic strains. We report that classical V. cholerae underwent sequential mutations in T6SS genetic determinants that initially exposed 2nd pandemic strains …

Oral Manifestations Of Tuberculosis, Diana V. Macri, Sandra Castellanos, Elvir Dincer

Publications and Research

This article will update the reader on tuberculosis and its oral manifestations.

After decades of decreasing incidence, tuberculosis resurgence is being seen in some global regions due to factors that include the human immunodeficiency virus (HIV) epidemic, increased immigration from countries with endemic tuberculosis, transmission of tuberculosis in crowded or unsanitary environments, and poor healthcare infrastructure. Additionally, this review is especially prescient considering the increasing prevalence of drug-resistant tuberculosis.

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 …

Pandemic Vibrio Cholerae Shuts Down Site-Specific Recombination To Retain An Interbacterial Defence Mechanism, Francis J. Santoriello, Lina Michel, Daniel Unterweger, Stefan Pukatzki

Publications and Research

Vibrio cholerae is an aquatic microbe that can be divided into three subtypes: harmless environmental strains, localised pathogenic strains, and pandemic strains causing global cholera outbreaks. Each type has a contact-dependent type VI secretion system (T6SS) that kills neighbouring competitors by translocating unique toxic effector proteins. Pandemic isolates possess identical effectors, indicating that T6SS effectors may affect pandemicity. Here, we show that one of the T6SS gene clusters (Aux3) exists in two states: a mobile, prophage-like element in a small subset of environmental strains, and a truncated Aux3 unique to and conserved in pandemic isolates. Environmental Aux3 can be readily …

Investigating The Impact Of The Nursing Practice Environment (Npe) On Central Line-Associated Bloodstream Infections (Clabsi) Among Older Adults In The Intensive Care Unit (Icu), Kristen A. Cribbs

Dissertations and Theses

Background: Health care–associated infections, resulting from treatment received for medical or surgical conditions in a health care setting, represent a critical public health and patient safety issue, exacting substantial medical, social, and economic costs. The costliest among the leading causes of preventable health care-associated infections is central-line associated bloodstream infections (CLABSI), to which older adults (age 65 years and older) are particularly susceptible, especially during intensive care unit (ICU) stays. A rich body of research has empirically linked the quality of the nursing practice environment (NPE) in hospitals to both positive and negative patient outcomes; yet, surprisingly few studies have …

Antibacterial, Antifungal, Antioxidant Activity And Polyphenol Content Of Aerial Parts And Bulbs Of Allium Schugnanicum., Saidbeg Satorov, F. Mirzoeva, Sh. Kurbonbekova, Sh. Satorov, M. Vakhidova, Vyacheslav Dushenkov

Publications and Research

Objective: То study of antibacterial, antifungal and antioxidant activity, and content of polyphenols in the bulb and aerial parts of an endemic species of onion A. schugnanicum. Methods: An ethanol-based extract was prepared from fresh plants. Total polyphenolic content (Folin) and ABTS antioxidant capacity assays were used to characterized extracts. Extracts obtained from bulbs, peduncle, and seeds demonstrated antibacterial activity against the reference Staphylococcus aureus (ATCC 4929), Pseudomonas aeruginosa (ATCC 4930) and Klebsiella pneumoniae (ATCC 4927) strains, as well as against the hospital strains of the same types of bacteria, i.e. strains isolated from inpatient surgical patients. Results: The study …

Plasmid Diversity And Phylogenetic Consistency In The Lyme Disease Agent Borrelia Burgdorferi, Sherwood R. Casjens, Eddie B. Gilcrease, Marija Vujadinovic, Emmanuel F. Mongodin, Benjamin J. Luft, Steven E. Schutzer, Claire M. Fraser, Wei-Gang Qiu

Publications and Research

Background: Bacteria from the genus Borrelia are known to harbor numerous linear and circular plasmids. We report here a comparative analysis of the nucleotide sequences of 236 plasmids present in fourteen independent isolates of the Lyme disease agent B. burgdorferi.

Results: We have sequenced the genomes of 14 B. burgdorferi sensu stricto isolates that carry a total of 236 plasmids. These individual isolates carry between seven and 23 plasmids. Their chromosomes, the cp26 and cp32 circular plasmids, as well as the lp54 linear plasmid, are quite evolutionarily stable; however, the remaining plasmids have undergone numerous non-homologous and often duplicative recombination …

Lesion-Specific Immune Response In Granulomas Of Patients With Pulmonary Tuberculosis: A Pilot Study, Selvakumar Subbian, Liana Tsenova, Mi-Jeong Kim, Helen C. Wainwright, Annalie Visser, Nirmalya Bandyopadhyay, Joel S. Bader, Petros C. Karakousis, Gabriele B. Murrmann, Linda-Gail Bekker, David G. Russell, Gilla Kaplan

Publications and Research

The formation and maintenance of granulomas is central to the host response to Mycobacterium tuberculosis (Mtb) infection. It is widely accepted that the lungs of patients with tuberculosis (TB) usually contain multiple infection foci, and that the granulomas evolve and differentiate independently, resulting in considerable heterogeneity. Although gene expression profiles of human blood cells have been proposed as biomarkers of Mtb infection and/or active disease, the immune profiles of discrete lesion types has not been studied extensively. Using histology, immunopathology and genome-wide transcriptome analysis, we explored the immunological profile of human lung TB granulomas. We show that although the different …