Bacterial Infections and Mycoses Commons^™

Pulmonary Surfactant Fortified With Cath-2 As A Novel Therapy For Bacterial Pneumonia, Brandon J. Baer

Western Research Forum

Background: Bacterial pneumonia is a leading cause of death worldwide, with high mortality rates persisting even after antibiotic treatment. Current treatments for pneumonia involve administration of antibiotics, however after the bacteria are killed they release toxic substances that induce inflammation and lung dysfunction. Host defense peptides represent a potential solution to this problem through their ability to down regulate inflammation. However, effective delivery to the lung is difficult because of the complex branching structure of the airways. My study addresses this delivery problem by using exogenous surfactant, a pulmonary delivery vehicle capable of improving spreading of these peptides throughout the …

Enhanced Control Of Mycobacterium Tuberculosis Extrapulmonary Dissemination In Mice By An Arabinomannan-Protein Conjugate Vaccine, R Prados-Rosales, L Carreno, T Cheng, C Blanc, B Weinrick, Aharona Glatman-Freedman, A Casadevall, S Hung, A Tripathi, J Xu, Aharona Glatman-Freedman, W Jacobs Jr., J Chan, S Porcelli, J Achkar, A Casadevall

NYMC Faculty Publications

Currently there are a dozen or so of new vaccine candidates in clinical trials for prevention of tuberculosis (TB) and each formulation attempts to elicit protection by enhancement of cell-mediated immunity (CMI). In contrast, most approved vaccines against other bacterial pathogens are believed to mediate protection by eliciting antibody responses. However, it has been difficult to apply this formula to TB because of the difficulty in reliably eliciting protective antibodies. Here, we developed capsular polysaccharide conjugates by linking mycobacterial capsular arabinomannan (AM) to either Mtb Ag85b or B. anthracis protective antigen (PA). Further, we studied their immunogenicity by ELISA and …

Outpatient Parenteral Antimicrobial Therapy In Pediatric Medicaid Enrollees., Jennifer Goldman, Troy Richardson, Jason G. Newland, Brian R. Lee, Jeffrey S. Gerber, Matt Hall, Matthew Kronman, Adam L. Hersh

Manuscripts, Articles, Book Chapters and Other Papers

Background: Outpatient parenteral antimicrobial therapy (OPAT) is overused in cases where highly bioavailable oral alternatives would be equally effective. However, the scope of OPAT use for children nationwide is poorly understood. Our objective was to characterize OPAT use and clinical outcomes for a large population of pediatric Medicaid enrollees treated with OPAT.

Methods: We analyzed the Truven MarketScan Medicaid claims database between 2009 and 2012. An OPAT episode was identified by capturing children with claims data indicating home infusion therapy for an intravenous antimicrobial. We characterized OPAT use by describing patient demographics, diagnoses, and antimicrobials prescribed. We categorized an antimicrobial …

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 …

Orientia Tsutsugamushi Secretes Two Ankyrin Repeat-Containing Effectors Via A Type 1 Secretion System To Inhibit Host Nf-Κb Function, Sean M. Evans

Theses and Dissertations

Scrub typhus is a potentially fatal infection that threatens one billion persons in the Asia-Pacific region and is caused by the obligate intracellular bacterium, Orientia tsutsugamushi. How this organism facilitates its intracellular survival and pathogenesis is poorly understood. Intracellular bacterial pathogens utilize the Type 1 (T1SS) or Type 4 secretion system (T4SS) to translocate ankyrin repeat-containing proteins (Anks) into the host cell to modulate host cell processes. The O. tsutsugamushi genome encodes one of the largest known bacterial Ank libraries as well as Type 1 and Type 4 secretion systems (T1SS and T4SS), which are expressed during infection. In …

Determining The Effects Of Methanol, Ethanol, Isopropanol, And Glycerol On Both Thermal Stability And Catalytic Activity Of Rv0045c, An Enzyme From M. Tuberculosis, Katelyn Baumer

Undergraduate Honors Thesis Collection

Tuberculosis (TB) is a highly infectious respiratory disease contracted through the inhalation of Mycobacterium tuberculosis. Serine hydrolases are abundant in M. tuberculosis and serve as a model for studying the inhibition of TB. Rv0045c is an example of such with little known regarding its biological function. Rv0045c was exposed to methanol, ethanol, isopropanol, or glycerol and the effects of varying concentration of these alcohols on the catalytic efficiency and thermal stability of the enzyme was determined. The thermal stability of Rv0045c was found to decrease with concentration of methanol, ethanol, or isopropanol. The opposite was true of the thermal stability …

Nitrosative Stress Sensing In Porphyromonas Gingivalis: Structure And Function Of The Heme Binding Transcriptional Regulator Hcpr, Benjamin R. Belvin

Theses and Dissertations

Porphyromonas gingivalis, a Gram negative anaerobe implicated in the progression of periodontal disease, is capable of surviving and causing infection despite high levels of reactive nitrogen species found in the oral cavity due to its efficient nitrosative stress response. HcpR is an important sensor-regulator that plays a vital step in the initiation of the nitrosative stress response in many Gram negative anaerobic bacteria. We employ a combination of X-ray crystallography, SAXS, resonance Raman spectroscopy, UV-Vis spectroscopy, and molecular biology techniques to better understand this key regulator. Knockout of the hcpR gene in W83 P. gingivalis results in the inability of …

Human Tear Fluid Reduces Culturability Of Contact Lens-Associated Pseudomonas Aeruginosa Biofilms But Induces Expression Of The Virulence-Associated Type Iii Secretion System, Yvonne T. Wu, Connie Tam, Lucia S. Zhu, David J. Evans, Suzanne M. J. Fleiszig

Faculty Publications & Research of the TUC College of Pharmacy

Purpose

The type III secretion system (T3SS) is a significant virulence determinant for Pseudomonas aeruginosa. Using a rodent model, we found that contact lens(CL)-related corneal infections were associated with lens surface biofilms. Here, we studied the impact of human tear fluid on CL-associated biofilm growth and T3SS expression.

Methods

P. aeruginosa biofilms were formed on contact lenses for up to 7 days with or without human tear fluid, then exposed to tear fluid for 5 or 24 h. Biofilms were imaged using confocal microscopy. Bacterial culturability was quantified by viable counts, and T3SS gene expression measured …

Biomarkers Of Sepsis: A Retrospective Approach, Jose M. Roberts

Williams Honors College, Honors Research Projects

Background: Biomarkers are taking the spotlight in becoming the norm for early diagnoses. Sepsis is an inflammatory disease that increases metabolic rate in children. The first biomarker is hyponatremia. Hyponatremia is a frequent electrolyte imbalance in clinical practice, often observed in children with inflammatory disease and infection. Presence of hyponatremia is associated with electrical signaling imbalances, inflammation and renal dysfunction. The clinical value of hyponatremia in pediatric patients is unknown. The C-reactive protein is a second biomarker. Its presence signifies that necrotic cells and inflammation are present.

Objectives: To evaluate the use of biomarkers in children seen in the Emergency …

Discovering A Novel Antifungal Target In Downstream Sterol Biosynthesis Using A Squalene Synthase Functional Motif, Kristin Brooke Linscott

Theses and Dissertations--Molecular and Cellular Biochemistry

The sterol biosynthetic pathway is essential for growth of all eukaryotic cells and the main target of antifungal agents. The emergence of resistance to these antifungals in an already ill patient population indicates a need to develop drugs that have a broad spectrum of activity among pathogenic fungi and have minimal patient toxicity. Squalene synthase is the first committed step in the sterol pathway and has been studied intensively for development of antifungal agents. While the overall architecture of this enzyme is identical throughout eukaryotes, it was shown that plant and animal genes cannot complement a squalene synthase knockout mutation …

Epidemiological Investigation Of Candida Species Causing Bloodstream Infection In Pediatric Small Bowel Transplant Recipients, Mallory J. Suhr, João Carlos Gomes-Neto, Nabaraj Banjara, Diana F. Florescu, David F. Mercer, Peter C. Iwen, Heather E. Hallen-Adams

Department of Food Science and Technology: Faculty Publications

Small bowel transplantation (SBT) can be a life-saving medical procedure. However, these recipients experience high risk of bloodstream infections caused by Candida. This research aims to characterize the SBT recipient gut microbiota over time following transplantation and investigate the epidemiology of candidemia in seven pediatric patients. Candida species from the recipients’ ileum and bloodstream were identified by internal transcribed spacer sequence and distinguished to strain by multilocus sequence typing and randomly amplified polymorphic DNA. Antifungal susceptibility of bloodstream isolates was determined against nine antifungals. Twenty-two ileostomy samples harbored at least one Candida species. Fungemia were caused by Candida parapsilosis …

Characterizing The Role Of Cpsa In Mycobacterial Pathogenesis, Amir Hassan

Undergraduate Research Symposium Posters

Mycobacterium tuberculosis infects one-third of the world’s population and causes an estimated 2 million deaths per year, more than any other single bacterial pathogen. The inadequacies of existing tuberculosis therapies demand the discovery of novel agents to treat M. tuberculosis infection, which requires mechanistic insight into the pathways involved in mycobacterial pathogenesis. We identified an unanticipated role of the M. tuberculosis protein CpsA in preventing phago-lysosome fusion by host macrophages, resulting in enhanced intracellular survival of bacteria within the host. Strains of M. tuberculosis lacking cpsA are severely attenuated in both macrophage and mouse models, thus establishing CpsA as a …

Mucosal Fluid Glycoprotein Dmbt1 Suppresses Twitching Motility And Virulence Of The Opportunistic Pathogen Pseudomonas Aeruginosa, Jianfang Li, Matteo E. O. Metruccio, David J. Evans, Suzanne M. J. Fleiszig

Faculty Publications & Research of the TUC College of Pharmacy

It is generally thought that mucosal fluids protect underlying epithelial surfaces against opportunistic infection via their antimicrobial activity. However, our published data show that human tear fluid can protect against the major opportunistic pathogen Pseudomonas aeruginosa independently of bacteriostatic activity. Here, we explored the mechanisms for tear protection, focusing on impacts of tear fluid on bacterial virulence factor expression. Results showed that tear fluid suppressed twitching motility, a type of surface-associated movement conferred by pili. Previously, we showed that twitching is critical for P. aeruginosa traversal of corneal epithelia, exit from epithelial cells after internalization, and corneal virulence. Inhibition …

Mc-Ppea As A New And More Potent Inhibitor Of Clp-Induced Sepsis And Pulmonary Inflammation Than Fk866., Peixin Huang, Mark W Lee, Keivan Sadrerafi, Daniel P. Heruth, Li Q. Zhang, Dev Maulik, Shui Qing Ye

Manuscripts, Articles, Book Chapters and Other Papers

Our previous study indicated that overexpression of nicotinamide phosphoribosyltransferase (NAMPT) aggravated acute lung injury, while knockdown of NAMPT expression attenuated ventilator-induced lung injury. Recently, we found that meta-carborane-butyl-3-(3-pyridinyl)-2E-propenamide (MC-PPEA, MC4), in which the benzoylpiperidine moiety of FK866 has been replaced by a carborane, displayed a 100-fold increase in NAMPT inhibition over FK866. Here, we determined the effects of MC4 and FK866 on cecal ligation and puncture (CLP) surgery-induced sepsis in C57BL/6J mice. MC4 showed stronger inhibitory effects than FK866 on CLP-induced mortality, serum tumor necrosis factor α (TNFα) levels, pulmonary myeloperoxidase activity, alveolar injury, and interleukin 6 and interleukin1β messenger …

Life-Threatening Hypercalcemia During Prodrome Of Pneumocystis Jiroveci Pneumonia In An Immunocompetent Infant, Judith Sebestyen Vansickle, Tarak Srivastava, Uri S. Alon

Manuscripts, Articles, Book Chapters and Other Papers

Severe hypercalcemia in infants is usually attributed to genetic etiologies and less commonly to acquired ones. An 8-week-old girl presented with failure to thrive, mild respiratory distress, and life-threatening hypercalcemia (23.5 mg/dL). Serum 1,25(OH)2-D) level was elevated and parathyroid hormone undetectable. Evaluation for genetic mutations and malignant etiologies of hypercalcemia was negative. Treatment with intravenous hydration, loop diuretic, and calcitonin failed to correct the hypercalcemia, which was subsequently controlled with bisphosphonate therapy. Due to progressive respiratory deterioration, a bronchopulmonary lavage was done on day 17 of her hospitalization disclosing Pneumocystis jiroveci infection. The subsequent immunological investigation showed no abnormalities. She …