Bacteria Commons^™

Refining The Optimal First Treatment For Pediatric Breast Abscesses, Kayla B. Briggs

Research Days

Background: We previously reported treatment and outcomes of children with untreated, not spontaneously draining (UTND) breast abscesses. What has not been well defined however are those with previously treated, not spontaneously draining (PTND) pediatric breast abscesses. In general, a more conservative approach is favored in children with breast abscesses to avoid damage to the developing breast bud.

Objectives/Goal: We sought to determine if care at a pediatric tertiary referral center impacts disease persistence rate.

Methods/Design: Following IRB approval, patientstherapy.

Results: In all, 114 patients met inclusion criteria, 96 in the UTND group and 18 in the PTND group ...

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 ...

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

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. This ...

Selection For Thermophilic Bacteria With Antibacterial Potential Along Fire-Affected Soils In Centralia, Pa, Lanie Urbanski

Senior Scholars Day

In this study, bacteria were analyzed from a near-surface environment impacted by the anthracite coal mine fire in Centralia, Pennsylvania. We hypothesized that the elevated soil temperatures created by the spread of the underground fire would provide an ideal environment for previously unstudied thermophilic bacteria. With nearly 3 million cases of antibiotic resistant bacterial infections annually, the identification of novel bacteria is critical to make new antibiotics. Surface soil samples were taken from boreholes across eight fire-impacted locations. Bacteria were isolated from these samples on actinomycetes isolation agar at an increased temperature of 50°C to mimic the soil environment ...

The High Prevalence Of Clostridioides Difficile Among Nursing Home Elders Associates With A Dysbiotic Microbiome, John P. Haran, Doyle V. Ward, Shakti K. Bhattarai, Ethan Loew, Protiva Dutta, Amanda Higgins, Beth A. Mccormick, Vanni Bucci

University of Massachusetts Medical School Faculty Publications

Clostridioides difficile disproportionally affects the elderly living in nursing homes (NHs). Our objective was to explore the prevalence of C. difficile in NH elders, over time and to determine whether the microbiome or other clinical factors are associated with C. difficile colonization. We collected serial stool samples from NH residents. C. difficile prevalence was determined by quantitative polymerase-chain reaction detection of Toxin genes tcdA and tcdB; microbiome composition was determined by shotgun metagenomic sequencing. We used mixed-effect random forest modeling machine to determine bacterial taxa whose abundance is associated with C. difficile prevalence while controlling for clinical covariates including demographics ...

Microbiological Study In A Gneissic Cave From Sri Lanka, With Special Focus On Potential Antimicrobial Activities, Ethige Isuru P. Silva, Pathmakumara Jayasingha, Saman Senanayake, Anura Dandeniya, Dona Helani Munasinghe

International Journal of Speleology

The emergence of antibiotic resistance is a global health crisis, thus the search for novel antimicrobial compounds has become a continuous necessity. Underexplored and extreme environments, such as cave ecosystems, have been identified as a promising potential source for the discovery of novel microorganisms with novel antimicrobial compounds (AMC). This study presents the first cave microbiological investigation in Sri Lanka, with a special preference for bioprospecting of novel AMC. The cave sediment characterization demonstrated the presence of close to strong acidic conditions (pH 3.1 – 3.3) and thus indicates the possibility of isolating acidophilic microorganisms. Eight cave wall/ceiling ...

The Mycobacterium Tuberculosis Transposon Sequencing Database (Mtbtndb): A Large-Scale Guide To Genetic Conditional Essentiality [Preprint], Adrian Jinich, Anisha Zaveri, Michael A. Dejesus, Emanuel Flores-Bautista, Clare M. Smith, Christopher M. Sassetti, Jeremy M. Rock, Sabine Ehrt, Dirk Schnappinger, Thomas R. Ioerger, Kyu Rhee

University of Massachusetts Medical School Faculty Publications

Characterization of gene essentiality across different conditions is a useful approach for predicting gene function. Transposon sequencing (TnSeq) is a powerful means of generating genome-wide profiles of essentiality and has been used extensively in Mycobacterium tuberculosis (Mtb) genetic research. Over the past two decades, dozens of TnSeq screens have been published, yielding valuable insights into the biology of Mtb in vitro, inside macrophages, and in model host organisms. However, these Mtb TnSeq profiles are distributed across dozens of research papers within supplementary materials, which makes querying them cumbersome and assembling a complete and consistent synthesis of existing data challenging. Here ...

Ifnγ And Inos-Mediated Alterations In The Bone Marrow And Thymus And Its Impact On Mycobacterium Avium-Induced Thymic Atrophy [Preprint], Palmira Barreira-Silva, Rita Melo-Miranda, Claudia Nobrega, Susana Roque, Cláudia Serre-Miranda, Margarida Borges, Daniela De Sá Calçada, Samuel M. Behar, Rui Appelberg, Margarida Correia-Neves

University of Massachusetts Medical School Faculty Publications

Disseminated infection with the high virulence strain of Mycobacterium avium 25291 lead to progressive thymic atrophy. We previously uncovered that M. avium-induced thymic atrophy is due to increased levels of glucocorticoids synergizing with nitric oxide (NO) produced by interferon gamma (IFNγ) activated macrophages. Where and how these mediators are playing, was yet to be understood. We hypothesized that IFNγ and NO might be affecting bone marrow (BM) T cell precursors and/or T cell differentiation in the thymus. We show that M. avium infection causes a reduction on the percentage of lymphoid-primed multipotent progenitors (LMPP) and common lymphoid progenitors ...

Cd4 T Cell Help Prevents Cd8 T Cell Exhaustion And Promotes Control Of Mycobacterium Tuberculosis Infection [Preprint], Yu-Jung Lu, Palmira Barreira-Silva, Shayla Boyce, Jennifer Powers, Kelly Cavallo, Samuel M. Behar

University of Massachusetts Medical School Faculty Publications

CD4 T cells are essential for immunity to tuberculosis because they produce cytokines including interferon-γ. Whether CD4 T cells act as “helper” cells to promote optimal CD8 T cell responses during Mycobacterium tuberculosis is unknown. Using two independent models, we show that CD4 T cell help enhances CD8 effector functions and prevents CD8 T cell exhaustion. We demonstrate synergy between CD4 and CD8 T cells in promoting the survival of infected mice. Purified helped, but not helpless, CD8 T cells efficiently restrict intracellular bacterial growth in vitro. Thus, CD4 T cell help plays an essential role in generating protective CD8 ...

Host Tropism Determination By Convergent Evolution Of Immunological Evasion In The Lyme Disease System [Preprint], Thomas M. Hart, Alan P. Dupuis, Ii, Danielle M. Tufts, Anna M. Blom, Simon Starkey, Ryan O. M. Rego, Sanjay Ram, Peter Kraiczy, Laura D. Kramer, Maria A. Diuk-Wasser, Sergios-Orestis Kolokotronis, Yi-Pin Lin

University of Massachusetts Medical School Faculty Publications

Microparasites selectively adapt in some hosts, known as host tropism. Transmitted through ticks and carried mainly by mammals and birds, the Lyme disease (LD) bacterium is a well-suited model to study such tropism. LD bacteria species vary in host ranges through mechanisms eluding characterization. By feeding ticks infected with different LD bacteria species, utilizing feeding chambers and live mice and quail, we found species-level differences of bacterial transmission. These differences localize on the tick blood meal, and complement, a defense in vertebrate blood, and a bacterial polymorphic protein, CspA, which inactivates complement by binding to a host complement inhibitor, FH ...

Sirtuin 3 Downregulation In Mycobacterium Tuberculosis-Infected Macrophages Reprograms Mitochondrial Metabolism And Promotes Cell Death, Lorissa J. Smulan, Nuria M. Martinez, Michael C. Kiritsy, Chido L. Kativhu, Kelly Cavallo, Christopher M. Sassetti, Amit Singhal, Heinz G. Remold, Hardy Kornfeld

Open Access Publications by UMMS Authors

Mycobacterium tuberculosis induces metabolic reprogramming in macrophages like the Warburg effect. This enhances antimicrobial performance at the expense of increased inflammation, which may promote a pathogen-permissive host environment. Since the NAD(+)-dependent protein deacetylase Sirtuin 3 (SIRT3) is an important regulator of mitochondrial metabolism and cellular redox homeostasis, we hypothesized that SIRT3 modulation mediates M. tuberculosis-induced metabolic reprogramming. Infection of immortalized and primary murine macrophages resulted in reduced levels of SIRT3 mRNA and protein and perturbation of SIRT3-regulated enzymes in the tricarboxylic acid cycle, electron transport chain, and glycolytic pathway. These changes were associated with increased reactive oxygen species and ...

Sociodemographic, Clinical Characteristics, And Outcomes Of Influenza Pneumonia Patients Admitted In A Tertiary Care Hospital In Karachi, Pakistan: Findings From A Cross-Sectional Study, Fazal Ur Rehman, Muhammad Arslan Ahmed, Kashif Aziz, Mahmooda Jabeen Ashraf, Tazein Amber, Sumera Aziz Ali

Section of Internal Medicine

Objective: To determine the sociodemographic, clinical characteristics, and outcomes of influenza pneumonia patients in tertiary care hospital, Karachi Pakistan.
Study design: A cross-sectional study.
Place and duration of study: The Aga Khan University Hospital Karachi Pakistan from January 2013 to December 2018. Methodology: All adult patients who were older than 18 years and suspected to have viral pneumonia were included in the study. Data were abstracted on 105 patients and were entered on preformed proforma after reviewing the files of patients.
Results: Ninety-four (89.5%) patients were influenza positive and 15.2% (n=16) had been vaccinated. Around 92.4 ...

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 ...

Exploring The Impact Of Ketodeoxynonulosonic Acid In Host-Pathogen Interactions Using Uptake And Surface Display By Nontypeable Haemophilus Influenzae, Sudeshna Saha, Sanjay Ram, Ajit Varki

Open Access Publications by UMMS Authors

Surface expression of the common vertebrate sialic acid (Sia) N-acetylneuraminic acid (Neu5Ac) by commensal and pathogenic microbes appears structurally to represent "molecular mimicry" of host sialoglycans, facilitating multiple mechanisms of host immune evasion. In contrast, ketodeoxynonulosonic acid (Kdn) is a more ancestral Sia also present in prokaryotic glycoconjugates that are structurally quite distinct from vertebrate sialoglycans. We detected human antibodies against Kdn-terminated glycans, and sialoglycan microarray studies found these anti-Kdn antibodies to be directed against Kdn-sialoglycans structurally similar to those on human cell surface Neu5Ac-sialoglycans. Anti-Kdn-glycan antibodies appear during infancy in a pattern similar to those generated following incorporation of ...

Investigation Of A Monoclonal Antibody Against Enterotoxigenic Escherichia Coli, Expressed As Secretory Iga1 And Iga2 In Plants, Audrey Y-H. Teh, Lisa A. Cavacini, Yue Hu, Ozan S. Kumru, Jian Xiong, David T. Bolick, Sangeeta B. Joshi, Clemens Grunwald-Gruber, Friedrich Altmann, Mark S. Klempner, Richard L. Guerrant, David B. Volkin, Yang Wang, Julian K-C. Ma

Open Access Publications by UMMS Authors

Passive immunization with antibodies is a promising approach against enterotoxigenic Escherichia coli diarrhea, a prevalent disease in LMICs. The objective of this study was to investigate expression of a monoclonal anti-ETEC CfaE secretory IgA antibody in N. benthamiana plants, with a view to facilitating access to ETEC passive immunotherapy. SIgA1 and SIgA2 forms of mAb 68-81 were produced by co-expressing the light and engineered heavy chains with J chain and secretory component in N. benthamiana. Antibody expression and assembly were compared with CHO-derived antibodies by SDS-PAGE, western blotting, size-exclusion chromatography and LC-MS peptide mapping. N-linked glycosylation was assessed by rapid ...

The Intestinal And Oral Microbiomes Are Robust Predictors Of Covid-19 Severity The Main Predictor Of Covid-19-Related Fatality [Preprint], Doyle V. Ward, Shakti Bhattarai, Mayra Rojas-Correa, Ayan Purkayastha, Devon Holler, Ming Da Qu, William G. Mitchell, Jason D. Yang, Samuel Fountain, Abigail Zeamer, Catherine Forconi, Gavin Fujimori, Boaz Odwar, Caitlin Cawley, Beth A. Mccormick, Ann M. Moormann, Mireya Wessolossky, Vanni Bucci, Ana Maldonado-Contreras

University of Massachusetts Medical School Faculty Publications

The reason for the striking differences in clinical outcomes of SARS-CoV-2 infected patients is still poorly understood. While most recover, a subset of people become critically ill and succumb to the disease. Thus, identification of biomarkers that can predict the clinical outcomes of COVID-19 disease is key to help prioritize patients needing urgent treatment. Given that an unbalanced gut microbiome is a reflection of poor health, we aim to identify indicator species that could predict COVID-19 disease clinical outcomes. Here, for the first time and with the largest COVID-19 patient cohort reported for microbiome studies, we demonstrated that the intestinal ...

Quantifying The Regulatory Role Of Individual Transcription Factors In Escherichia Coli [Preprint], Sunil Guharajan, Shivani Chhabra, Vinuselvi Parisutham, Robert C. Brewster

University of Massachusetts Medical School Faculty Publications

Transcription factors (TFs) modulate gene expression by binding to regulatory DNA sequences surrounding target genes. To isolate the fundamental regulatory interactions of E. coli TFs, we measure regulation of TFs acting on synthetic target genes that are designed to isolate the individual TF regulatory effect. This data is interpreted through a thermodynamic model that decouples the role of TF copy number and TF binding affinity from the interactions of the TF on RNA polymerase through two distinct mechanisms: (de)stabilization of the polymerase and (de)acceleration of transcription initiation. We find the contribution of each mechanism towards the observed regulation ...

Covid-19 Presenting With Spontaneous Pneumothorax, Intisar Ahmed, Hunaina Shahab, Muhammad Arslan Ahmed, Muhammad Sohaib

Section of Cardiology

The coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease mainly affects respiratory system. Its common clinical findings include fever, cough and shortness of breath. Characteristic radiological features of the disease include peripherally distributed, bilateral ground-glass opacities, predominantly involving the lower lung zones. In this report, we present a case of COVID-19 disease presenting with spontaneous pneumothorax. A 26-year male patient was admitted to the Emergency Department with fever, dry cough, shortness of breath and right-sided chest pain. Radiographic imaging of the patient revealed pneumothorax on the right and peripherally distributed non-homogenous opacification ...

Host-Pathogen Genetic Interactions Underlie Tuberculosis Susceptibility In Genetically Diverse Mice [Preprint], Clare M. Smith, Richard E. Baker, Megan K. Proulx, Bibhuti B. Mishra, Jarukit E. Long, Michael C. Kiritsy, Michelle Bellerose, Andrew J. Olive, Kenan C. Murphy, Kadamba Papavinasasundaram, Frederick Boehm, Charlotte Reames, Christopher M. Sassetti

University of Massachusetts Medical School Faculty Publications

The outcome of an encounter with Mycobacterium tuberculosis (Mtb) depends on the pathogen’s ability to adapt to the heterogeneous immune response of the host. Understanding this interplay has proven difficult, largely because experimentally tractable small animal models do not recapitulate the heterogenous disease observed in natural infections. We leveraged the genetically diverse Collaborative Cross (CC) mouse panel in conjunction with a library of Mtb mutants to associate bacterial genetic requirements with host genetics and immunity. We report that CC strains vary dramatically in their susceptibility to infection and represent reproducible models of qualitatively distinct immune states. Global analysis of ...