Medicine and Health Sciences Commons^™

The Brief Case:, Eileen M Burd, Ahmed Babiker, Jessica K Fairley, Divya Bhamidipati, Laila E Woc-Colburn, Blaine A Mathison

Journal Articles

No abstract provided.

Trypanosoma Cruzi Modulates Piwi-Interacting Rna Expression In Primary Human Cardiac Myocytes During The Early Phase Of Infection, Kayla J. Rayford, Ayorinde Cooley, Ashutosh Arun, Girish Rachakonda, Yulia Kleschenko, Fernando Villalta, Siddharth Pratap, Maria F. Lima, Pius N. Nde

Publications and Research

Trypanosoma cruzi dysregulates the gene expression profile of primary human cardiomyocytes (PHCM) during the early phase of infection through a mechanism which remains to be elucidated. The role that small non-coding RNAs (sncRNA) including PIWI-interacting RNA (piRNA) play in regulating gene expression during the early phase of infection is unknown. To understand how T. cruzi dysregulate gene expression in the heart, we challenged PHCM with T. cruzi trypomastigotes and analyzed sncRNA, especially piRNA, by RNA-sequencing. The parasite induced significant differential expression of host piRNAs, which can target and regulate the genes which are important during the early infection phase. An …

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 …

Carbapenem-Resistant Enterobacteriaceae (Cre): Epidemiology, Duration Of Carriage, And Progression To Infection In A Large Healthcare System In Miami, Fl, Adriana Jimenez

FIU Electronic Theses and Dissertations

Carbapenem-resistant Enterobacteriaceae (CRE) are multidrug-resistant organisms (MDRO) considered by the CDC as an urgent public health threat that is spreading globally. Little is known about the epidemiology of CRE in Miami, FL. The purpose of this dissertation was to 1) Evaluate trends in the epidemiology of CRE among patients admitted to the acute care facilities of the largest healthcare system in Miami, FL between 2012 and 2016, 2) Identify factors associated with progressing to infection among patients colonized with carbapenemase-producing Enterobacteriaceae (CPE), and 3) Determine the duration of CPE carriage and factors associated with long-term carriage in our cohort.

A …

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 …

Chain-Selective Isotopic Labeling Of The Heterodimeric Type Iii Secretion Chaperone, Scc4:Scc1, Reveals The Total Structural Rearrangement Of The Chlamydia Trachomatis Bi-Functional Protein, Scc4, Thilini O. Ukwaththage, Samantha M. Keane, Li Shen, Megan A. Macnaughtan

School of Medicine Faculty Publications

Scc4 is an unusual bi-functional protein from Chlamydia trachomatis (CT) that functions as a type III secretion system (T3SS) chaperone and an RNA polymerase (RNAP)-binding protein. Both functions require interactions with protein partners during specific stages of the CT developmental cycle. As a T3SS chaperone, Scc4 binds Scc1 during the late stage of development to form a heterodimer complex, which chaperones the essential virulence effector, CopN. During the early-middle stage of development, Scc4 regulates T3SS gene expression by binding the σ66-containing RNAP holoenzyme. In order to study the structure and association mechanism of the Scc4:Scc1 T3SS chaperone complex using nuclear …

Neurotropic Lineage Iii Strains Of Listeria Monocytogenes Disseminate To The Brain Without Reaching High Titer In The Blood, Taylor E. Senay, Jessica L. Ferrell, Filip G. Garrett, Taylor M. Albrecht, Jooyoung Cho, Katie L. Alexander, Tanya Myers-Morales, Olivia F. Grothaus, Sarah E. F. D'Orazio

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Listeria monocytogenes is thought to colonize the brain using one of three mechanisms: direct invasion of the blood-brain barrier, transportation across the barrier by infected monocytes, and axonal migration to the brain stem. The first two pathways seem to occur following unrestricted bacterial growth in the blood and thus have been linked to immunocompromise. In contrast, cell-to-cell spread within nerves is thought to be mediated by a particular subset of neurotropic L. monocytogenes strains. In this study, we used a mouse model of foodborne transmission to evaluate the neurotropism of several L. monocytogenes isolates. Two strains preferentially colonized the brain …

Staphylococcus Aureus Atp Synthase Promotes Biofilm Persistence By Influencing Innate Immunity, Megan E. Bosch, Blake P. Bertrand, Cortney E. Heim, Abdulelah A. Alqarzaee, Sujata S. Chaudhari, Amy L. Aldrich, Paul D. Fey, Vinai C. Thomas, Tammy Kielian

Journal Articles: Pathology and Microbiology

No abstract provided.

Which Sample Type Is Better For Xpert Mtb/Rif To Diagnose Adult And Pediatric Pulmonary Tuberculosis?, Mengyuan Lyu, Jian Zhou, Yuhui Cheng, Weelic Chong, Kang Wu, Teng Fang, Tianbo Fu, Binwu Ying

Department of Medicine Faculty Papers

OBJECTIVE: This review aimed to identify proper respiratory-related sample types for adult and pediatric pulmonary tuberculosis (PTB), respectively, by comparing performance of Xpert MTB/RIF when using bronchoalveolar lavage (BAL), induced sputum (IS), expectorated sputum (ES), nasopharyngeal aspirates (NPAs), and gastric aspiration (GA) as sample.

METHODS: Articles were searched in Web of Science, PubMed, and Ovid from inception up to 29 June 2020. Pooled sensitivity and specificity were calculated, each with a 95% confidence interval (CI). Quality assessment and heterogeneity evaluation across included studies were performed.

RESULTS: A total of 50 articles were included. The respective sensitivity and specificity were 87% …

Cell Cycle Regulation In Macrophages And Susceptibility To Hiv-1, Isabella A. T. M. Ferreira, James Zachary Porterfield, Ravindra K. Gupta, Petra Mlcochova

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Macrophages are the first line of defence against invading pathogens. They play a crucial role in immunity but also in regeneration and homeostasis. Their remarkable plasticity in their phenotypes and function provides them with the ability to quickly respond to environmental changes and infection. Recent work shows that macrophages undergo cell cycle transition from a G0/terminally differentiated state to a G1 state. This G0-to-G1 transition presents a window of opportunity for HIV-1 infection. Macrophages are an important target for HIV-1 but express high levels of the deoxynucleotide-triphosphate hydrolase SAMHD1, which restricts viral DNA synthesis by decreasing levels of dNTPs. While …

Deacetylation Of Hsd17b10 By Sirt3 Regulates Cell Growth And Cell Resistance Under Oxidative And Starvation Stresses., Lu Liu, Shuaiyi Chen, Miao Yu, Chenxu Ge, Mengmeng Ren, Boya Liu, Xin Yang, Thomas W Christian, Ya-Ming Hou, Junhua Zou, Wei-Guo Zhu, Jianyuan Luo

Department of Biochemistry and Molecular Biology Faculty Papers

17-beta-hydroxysteroid dehydrogenase 10 (HSD17B10) plays an important role in mitochondrial fatty acid metabolism and is also involved in mitochondrial tRNA maturation. HSD17B10 missense mutations cause HSD10 mitochondrial disease (HSD10MD). HSD17B10 with mutations identified from cases of HSD10MD show loss of function in dehydrogenase activity and mitochondrial tRNA maturation, resulting in mitochondrial dysfunction. It has also been implicated to play roles in the development of Alzheimer disease (AD) and tumorigenesis. Here, we found that HSD17B10 is a new substrate of NAD-dependent deacetylase Sirtuin 3 (SIRT3). HSD17B10 is acetylated at lysine residues K79, K99 and K105 by the acetyltransferase CBP, and the …

Lyssavirus Vaccine With A Chimeric Glycoprotein Protects Across Phylogroups, Christine R Fisher, David E Lowe, Todd G Smith, Yong Yang, Christina L Hutson, Christoph Wirblich, Gino Cingolani, Matthias J. Schnell

Department of Biochemistry and Molecular Biology Faculty Papers

Rabies is nearly 100% lethal in the absence of treatment, killing an estimated 59,000 people annually. Vaccines and biologics are highly efficacious when administered properly. Sixteen rabies-related viruses (lyssaviruses) are similarly lethal, but some are divergent enough to evade protection from current vaccines and biologics, which are based only on the classical rabies virus (RABV). Here we present the development and characterization of LyssaVax, a vaccine featuring a structurally designed, functional chimeric glycoprotein (G) containing immunologically important domains from both RABV G and the highly divergent Mokola virus (MOKV) G. LyssaVax elicits high titers of antibodies specific to both RABV …

Thrombospondin-1 Plays An Essential Role In Yes-Associated Protein Nuclear Translocation During The Early Phase Of Trypanosoma Cruzi Infection In Heart Endothelial Cells, Ashutosh Arun, Kayla J. Rayford, Ayorinde Cooley, Girish Rachakonda, Fernando Villalta, Siddharth Pratap, Maria F. Lima, Nader Sheibani, Pius N. Nde

Publications and Research

The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease. This neglected tropical disease causes severe morbidity and mortality in endemic regions. About 30% of T. cruzi infected individuals will present with cardiac complications. Invasive trypomastigotes released from infected cells can be carried in the vascular endothelial system to infect neighboring and distant cells. During the process of cellular infection, the parasite induces host cells, to increase the levels of host thrombospondin-1 (TSP-1), to facilitate the process of infection. TSP-1 plays important roles in the functioning of vascular cells, including vascular endothelial cells with important implications in cardiovascular …

Are You Still On The Fence About Wearing A Mask?, Richard Davis

Articles, Abstracts, and Reports

Microbe-containing droplets are produced by coughing, talking, singing and sneezing. Masks are effective at blocking most of these droplets, even when up close.

Clinical And Basic Research Investigations Into The Long‐Term Effects Of Prenatal Opioid Exposure On Brain Development, Taylor Boggess, W. Chris Risher

Biomedical Sciences

Coincident with the opioid epidemic in the United States has been a dramatic increase in the number of children born with neonatal abstinence syndrome (NAS), a form of withdrawal resulting from opioid exposure during pregnancy. Many research efforts on NAS have focused on short‐term care, including acute symptom treatment and weaning of the infants off their drug dependency prior to authorizing their release. However, investigations into the long‐term effects of prenatal opioid exposure (POE) on brain development, from the cellular to the behavioral level, have not been as frequent. Given the importance of the perinatal period for human brain development, …

The Trait Repertoire Enabling Cyanobacteria To Bloom Assessed Through Comparative Genomic Complexity And Metatranscriptomics, Huansheng Cao, Yohei Shimura, Morgan M. Steffen, Zhou Yang, Jingrang Lu, Allen Joel, Landon Jenkins, Masanobu Kawachi, Yanbin Yin, Ferran Garcia-Pichel

Food for Health: Publications

Water bloom development due to eutrophication constitutes a case of niche specialization among planktonic cyanobacteria, but the genomic repertoire allowing bloom formation in only some species has not been fully characterized. We posited that the habitat relevance of a trait begets its underlying genomic complexity, so that traits within the repertoire would be differentially more complex in species successfully thriving in that habitat than in close species that cannot. To test this for the case of bloom-forming cyanobacteria, we curated 17 potentially relevant query metabolic pathways and five core pathways selected according to existing ecophysiological literature. The available 113 genomes …

Staphylococcus Aureus May Be Living In Your Nasal Cavity Right Now, Hannah Pedersen

Research and Scholarship Symposium Posters

Staphylococcus aureus is a dual role bacterium and is able to live commensally in some patients, but can cause disease in others. Methicillin resistant S. aureus (MRSA) causes life threatening disease in patients and can be very hard to treat since it is resistant to many antibiotics. In order for S. aureus to wreak havoc on the body, it must be able to have specific genes expressed to secrete toxins. These toxins are what causes the patients to get a wide variety of symptoms like boils, scalded skin, toxic shock syndrome, pneumonia or sepsis. This study tested eleven different isolates …

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 …

Approaches To Overcome Flow Cytometry Limitations In The Analysis Of Cells From Veterinary Relevant Species, Julia Hunka, John T. Riley, Gudrun F. Debes

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: Flow cytometry is a powerful tool for the multiparameter analysis of leukocyte subsets on the single cell level. Recent advances have greatly increased the number of fluorochrome-labeled antibodies in flow cytometry. In particular, an increase in available fluorochromes with distinct excitation and emission spectra combined with novel multicolor flow cytometers with several lasers have enhanced the generation of multidimensional expression data for leukocytes and other cell types. However, these advances have mainly benefited the analysis of human or mouse cell samples given the lack of reagents for most animal species. The flow cytometric analysis of important veterinary, agricultural, wildlife, …

A Decerebrating Female: A Rare Presentation Of Acute Disseminated Encephalomyelitis Due To Measles, Natasha Del Rio, Yordan Orive, Andres Sobrado, Ruben Cabrera, Ilde Manuel Lee, Troy Hoang, Sherard Lacaille, Ricardo Garcia-Rivera, Robert Hernandez

Internal Medicine

No abstract provided.

Alteration Of The Gut Microbiome In Normal And Overweight School Children From Selangor With Lactobacillus Fermented Milk Administration, Narcisse Joseph, Jonathan B. Clayton, Susan L. Hoops, Carter A. Linhardt, Amalia Mohd Hashim, Barakatun Nisak Mohd Yusof, Suresh Kumar, Syafinaz Amin Nordin

Food for Health: Publications

Childhood obesity is a serious public health problem worldwide. Perturbations in the gut microbiota composition have been associated with the development of obesity in both children and adults. Probiotics, on the other hand, are proven to restore the composition of the gut microbiome which helps reduce the development of obesity. However, data on the effect of probiotics on gut microbiota and its association with childhood obesity is limited. This study aims to determine the effect of probiotics supplement intervention on gut microbiota profiles in obese and normal-weight children. A total of 37 children, 17 normal weight, and 20 overweight school …

Stool Microbiome, Ph And Short/Branched Chain Fatty Acids In Infants Receiving Extensively Hydrolyzed Formula, Amino Acid Formula, Or Human Milk Through Two Months Of Age, Car Reen Kok, Bradford Brabec, Maciej Chichlowski, Cheryl L. Harris, Nancy Moore, Jennifer L. Wampler, Jon Vanderhoof, Devin Rose, Robert Hutkins

Food for Health: Publications

CRISPR–Cas is an anti-viral mechanism of prokaryotes that has been widely adopted for genome editing. To make CRISPR–Cas genome editing more controllable and safer to use, anti-CRISPR proteins have been recently exploited to prevent excessive/prolonged Cas nuclease cleavage. Anti-CRISPR (Acr) proteins are encoded by (pro)phages/(pro)viruses, and have the ability to inhibit their host’s CRISPR–Cas systems. We have built an online database AcrDB (http://bcb.unl.edu/AcrDB) by scanning ∼19 000 genomes of prokaryotes and viruses with AcrFinder, a recently developed AcrAca (Acr-associated regulator) operon prediction program. Proteins in Acr-Aca operons were further processed by two machine learning-based programs (AcRanker and PaCRISPR) to obtain …

Prevalence Of The Hypervirulent Nap1/Bi/027 Strain Of C. Difficile In Southwestern Virginia And Risk Factors Associated With Infection, Andrew O. Hanna, Anthony Baffoe-Bonnie, Shikha Vasudeva

Graduate Medical Education (GME) Resident and Fellow Research Day Posters

C. difficile infection (CDI) incidence has increased over the last several decades. The BI/NAP1/027 ribotype was discovered in 2005 and has since been responsible for multiple outbreaks in the US and Canada. This subtype of C. Difficile is known to be more virulent in vivo and produce more severe disease. Limited regional data of the prevalence of this ribotype is available, which could help guide treatment. Using infection control data from a large regional hospital and a VA medical center, this study documented the prevalence of the 027 ribotype in Southwest Virginia. Patients were included if they were tested at …

Fluorescent Sensor Arrays Can Predict And Quantify The Composition Of Multicomponent Bacterial Samples, Denis Svechkarev, Marat Sadykov, Lucas J. Houser, Kenneth W. Bayles, Aaron M. Mohs

Journal Articles: Pathology and Microbiology

Fast and reliable identification of infectious disease agents is among the most important challenges for the healthcare system. The discrimination of individual components of mixed infections represents a particularly difficult task. In the current study we further expand the functionality of a ratiometric sensor array technology based on small-molecule environmentally-sensitive organic dyes, which can be successfully applied for the analysis of mixed bacterial samples. Using pattern recognition methods and data from pure bacterial species, we demonstrate that this approach can be used to quantify the composition of mixtures, as well as to predict their components with the accuracy of ~80% …

Neutrophils Are Mediators Of Metastatic Prostate Cancer Progression In Bone, Diane L. Costanzo-Garvey, Tyler Keeley, Adam J. Case, Gabrielle F. Watson, Massar Alsamraae, Yangsheng Yu, Kaihong Su, Cortney E. Heim, Tammy Kielian, Colm Morrissey, Jeremy S Frieling, Leah M. Cook

Journal Articles: Pathology and Microbiology

Bone metastatic prostate cancer (BM-PCa) significantly reduces overall patient survival and is currently incurable. Current standard immunotherapy showed promising results for PCa patients with metastatic, but less advanced, disease (i.e., fewer than 20 bone lesions) suggesting that PCa growth in bone contributes to response to immunotherapy. We found that: (1) PCa stimulates recruitment of neutrophils, the most abundant immune cell in bone, and (2) that neutrophils heavily infiltrate regions of prostate tumor in bone of BM-PCa patients. Based on these findings, we examined the impact of direct neutrophil-prostate cancer interactions on prostate cancer growth. Bone marrow neutrophils directly induced apoptosis …

Tlr2 And Caspase-1 Signaling Are Critical For Bacterial Containment But Not Clearance During Craniotomy-Associated Biofilm Infection, Amy L. Aldrich, Cortney E. Heim, Wen Shi, Rachel W. Fallet, Bin Duan, Tammy Kielian

Journal Articles: Pathology and Microbiology

BACKGROUND: A craniotomy is required to access the brain for tumor resection or epilepsy treatment, and despite precautionary measures, infectious complications occur at a frequency of 1-3%. Approximately half of craniotomy infections are caused by Staphylococcus aureus (S. aureus) that forms a biofilm on the bone flap, which is recalcitrant to antibiotics. Our prior work in a mouse model of S. aureus craniotomy infection revealed a critical role for myeloid differentiation factor 88 (MyD88) in bacterial containment and pro-inflammatory mediator production. Since numerous receptors utilize MyD88 as a signaling adaptor, the current study examined the importance of Toll-like receptor 2 …

An Integrated Computational And Experimental Study To Investigate Staphylococcus Aureus Metabolism, Mohammad Mazharul Islam, Vinai Chittezham Thomas, Matthew Van Beek, Jong-Sam Ahn, Abdulelah A. Alqarzaee, Chunyi Zhou, Paul D. Fey, Kenneth W. Bayles, Rajib Saha

Journal Articles: Pathology and Microbiology

Staphylococcus aureus is a metabolically versatile pathogen that colonizes nearly all organs of the human body. A detailed and comprehensive knowledge of staphylococcal metabolism is essential to understand its pathogenesis. To this end, we have reconstructed and experimentally validated an updated and enhanced genome-scale metabolic model of S. aureus USA300_FPR3757. The model combined genome annotation data, reaction stoichiometry, and regulation information from biochemical databases and previous strain-specific models. Reactions in the model were checked and fixed to ensure chemical balance and thermodynamic consistency. To further refine the model, growth assessment of 1920 nonessential mutants from the Nebraska Transposon Mutant Library …

First-Time Characterization Of Viable But Non-Culturable Proteus Mirabilis: Induction And Resuscitation, Reham Wasfi, G. R. Abdellatif, H. M. Elshishtawy, Hossam M. Ashour

USF St. Petersburg campus Faculty Publications

Pathogenic bacteria can enter into a viable but non-culturable (VBNC) state under unfavourable conditions. Proteus mirabilis is responsible for dire clinical consequences including septicaemia, urinary tract infections and pneumonia, but is not a species previously known to enter VBNC state. We suggested that stress-induced P. mirabilis can enter a VBNC state in which it retains virulence. P. mirabilis isolates were incubated in extreme osmotic pressure, starvation, low temperature and low pH to induce a VBNC state. Resuscitation was induced by temperature upshift and inoculation in tryptone soy broth with Tween 20 and brain heart infusion broth. Cellular ultrastructure and gene …

Monocyte Metabolic Reprogramming Promotes Pro-Inflammatory Activity And Staphylococcus Aureus Biofilm Clearance, Kelsey J. Yamada, Cortney E. Heim, Xinyuan Xi, Kuldeep S. Attri, Dezhen Wang, Wenting Zhang, Pankaj K. Singh, Tatiana K. Bronich, Tammy Kielian

Journal Articles: Pathology and Microbiology

Biofilm-associated prosthetic joint infections (PJIs) cause significant morbidity due to their recalcitrance to immune-mediated clearance and antibiotics, with Staphylococcus aureus (S. aureus) among the most prevalent pathogens. We previously demonstrated that S. aureus biofilm-associated monocytes are polarized to an anti-inflammatory phenotype and the adoptive transfer of pro-inflammatory macrophages attenuated biofilm burden, highlighting the critical role of monocyte/macrophage inflammatory status in dictating biofilm persistence. The inflammatory properties of leukocytes are linked to their metabolic state, and here we demonstrate that biofilm-associated monocytes exhibit a metabolic bias favoring oxidative phosphorylation (OxPhos) and less aerobic glycolysis to facilitate their anti-inflammatory activity and biofilm …

Stochastic Expression Of Sae-Dependent Virulence Genes During Staphylococcus Aureus Biofilm Development Is Dependent On Saes, Elizabeth A. Delmain, Derek E. Moormeier, Jennifer L. Endres, Rebecca E. Hodges, Marat R. Sadykov, Alexander R. Horswill, Kenneth W. Bayles

Journal Articles: Pathology and Microbiology

The intricate process of biofilm formation in the human pathogen Staphylococcus aureus involves distinct stages during which a complex mixture of matrix molecules is produced and modified throughout the developmental cycle. Early in biofilm development, a subpopulation of cells detaches from its substrate in an event termed “exodus” that is mediated by SaePQRS-dependent stochastic expression of a secreted staphylococcal nuclease, which degrades extracellular DNA within the matrix, causing the release of cells and subsequently allowing for the formation of metabolically heterogenous microcolonies. Since the SaePQRS regulatory system is involved in the transcriptional control of multiple S. aureus virulence factors, the …