Medical Microbiology Commons^™

Comprehensive In Vitro And In Vivo Evaluation Of Therapeutic Potential Of Bacopa-Derived Asiatic Acid Against A Human Oral Pathogen Streptococcus Mutans, Rajendran Jeyasri, Pandiyan Muthuramalingam, Arumugam Priya, Rajaiah Alexpandi, N. R. Siva Shanmugam, Saminathan Nivetha, Hyunsuk Shin, Shunmugiah Karutha Pandian, Arumugam Veera Ravi, Manikandan Ramesh

Food for Health: Publications

Dental caries is a common human oral disease worldwide, caused by an acid-producing bacteria Streptococcus mutans. The use of synthetic drugs and antibiotics to prevent dental caries has been increasing, but this can lead to severe side effects. To solve this issue, developing and developed countries have resorted to herbal medicines as an alternative to synthetic drugs for the treatment and prevention of dental caries. Therefore, there is an urgent need for plant-derived products to treat such diseases. Bacopa monnieri, a well-documented medicinal plant, contains 52 phytocompounds, including the pentacyclic triterpenoid metabolite known as asiatic acid (ASTA). Hence, …

Antibiotic-Induced Changes In Efflux Transporter Expression: A Key Factor In Pseudomonas Aeruginosa Biofilm Resistance, Zara Imtiaz, Avinash Chatoo, Will Wang, Weiqi Li, Paramita Basu

Touro College of Pharmacy (New York) Publications and Research

Listed by WHO as an antibiotic-resistant priority pathogen, Pseudomonas aeruginosa(P.A.) is a serious threat in nosocomial infections. Its high antibiotic resistance is attributed to major mechanisms that can be categorized into intrinsic, acquired, and adaptive resistance. This study tests the ability of three commonly used antibiotics to inhibit new biofilm formation and eradicate mature biofilm growth, as well as investigate changes in the expression levels of selected genes coding for multidrug efflux pumps in P.A. planktonic cells and biofilms before and after treatment with antibiotics to provide a conceptual estimate of the activity of the efflux transporters that work to …

Jag1/2 Maintain Esophageal Homeostasis And Suppress Foregut Tumorigenesis By Restricting The Basal Progenitor Cell Pool, Haidi Huang, Yu Jiang, Jiangying Liu, Dan Luo, Jianghong Yuan, Rongzi Mu, Xiang Yu, Donglei Sun, Jihong Lin, Qiyue Chen, Xinjing Li, Ming Jiang, Jianming Xu, Bo Chu, Chengqian Yin, Lei Zhang, Youqiong Ye, Bo Cao, Qiong Wang, Yongchun Zhang

Faculty, Staff and Students Publications

Basal progenitor cells are crucial for maintaining foregut (the esophagus and forestomach) homeostasis. When their function is dysregulated, it can promote inflammation and tumorigenesis. However, the mechanisms underlying these processes remain largely unclear. Here, we employ genetic mouse models to reveal that Jag1/2 regulate esophageal homeostasis and foregut tumorigenesis by modulating the function of basal progenitor cells. Deletion of Jag1/2 in mice disrupts esophageal and forestomach epithelial homeostasis. Mechanistically, Jag1/2 deficiency impairs activation of Notch signaling, leading to reduced squamous epithelial differentiation and expansion of basal progenitor cells. Moreover, Jag1/2 deficiency exacerbates the deoxycholic acid (DCA)-induced squamous epithelial injury and …

Seasonality, Clinical Characteristics, And Outcomes Of Respiratory Syncytial Virus Disease By Subtype Among Children Aged <5 Years: New Vaccine Surveillance Network, United States, 2016-2020, Ariana P Toepfer, Justin Z Amarin, Andrew J Spieker, Laura S Stewart, Mary Allen Staat, Elizabeth P Schlaudecker, Geoffrey A Weinberg, Peter G Szilagyi, Janet A Englund, Eileen J Klein, Marian G Michaels, John V Williams, Rangaraj Selvarangan, Christopher J Harrison, Joana Y Lively, Pedro A Piedra, Vasanthi Avadhanula, Brian Rha, James Chappell, Meredith Mcmorrow, Heidi Moline, Natasha B Halasa

Faculty, Staff and Students Publications

BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory illnesses in children. RSV can be broadly categorized into 2 major subtypes: A and B. RSV subtypes have been known to cocirculate with variability in different regions of the world. Clinical associations with viral subtype have been studied among children with conflicting findings such that no conclusive relationships between RSV subtype and severity have been established.

METHODS: During 2016-2020, children aged/guardian interviews, chart reviews, and collection of midturbinate nasal plus/minus throat swabs for RSV (RSV-A, RSV-B, and untyped) using reverse transcription polymerase chain reaction.

RESULTS: Among 6398 RSV-positive …

Standard Rodent Diets Differentially Impact Alcohol Consumption, Preference, And Gut Microbiome Diversity, Aline Zaparte, Evan Dore, Selby White, Franciely Paliarin, Cameron Gabriel, Katherine Copenhaver, Samhita Basavanhalli, Emily Garcia, Rishith Vaddavalli, Meng Luo, Christopher M. Taylor, David Allen Welsh, Rajani Maiya

School of Graduate Studies Faculty Publications

Alcohol use disorder (AUD) is a complex and widespread disease with limited pharmacotherapies. Preclinical animal models of AUD use a variety of voluntary alcohol consumption procedures to recapitulate different phases of AUD, including binge alcohol consumption and dependence. However, voluntary alcohol consumption in mice is widely variable, making it difficult to reproduce results across labs. Accumulating evidence indicates that different brands of commercially available rodent chow can profoundly influence alcohol intake. In this study, we investigated the effects of three commercially available and widely used rodent diet formulations on alcohol consumption and preference in C57BL/6 J mice using the 24 …

Evaluation Of Fusobacterium Nucleatum Enoyl-Acp Reductase (Fabk) As A Narrow-Spectrum Drug Target, Jacob T Rutherford, Kristiana Avad, Chetna Dureja, Krissada Norseeda, Bibek Gc, Chenggang Wu, Dianqing Sun, Kirk E Hevener, Julian G Hurdle

Faculty, Staff and Student Publications

Fusobacterium nucleatum, a pathobiont inhabiting the oral cavity, contributes to opportunistic diseases, such as periodontal diseases and gastrointestinal cancers, which involve microbiota imbalance. Broad-spectrum antimicrobial agents, while effective against F. nucleatum infections, can exacerbate dysbiosis. This necessitates the discovery of more targeted narrow-spectrum antimicrobial agents. We therefore investigated the potential for the fusobacterial enoyl-ACP reductase II (ENR II) isoenzyme FnFabK (C4N14_ 04250) as a narrow-spectrum drug target. ENRs catalyze the rate-limiting step in the bacterial fatty acid synthesis pathway. Bioinformatics revealed that of the four distinct bacterial ENR isoforms, F. nucleatum specifically encodes FnFabK. Genetic studies revealed …

Mustang: Multi-Sample Spatial Transcriptomics Data Analysis With Cross-Sample Transcriptional Similarity Guidance, Seyednami Niyakan, Jianting Sheng, Yuliang Cao, Xiang Zhang, Zhan Xu, Ling Wu, Stephen T C Wong, Xiaoning Qian

Faculty, Staff and Students Publications

Spatially resolved transcriptomics has revolutionized genome-scale transcriptomic profiling by providing high-resolution characterization of transcriptional patterns. Here, we present our spatial transcriptomics analysis framework, MUSTANG (MUlti-sample Spatial Transcriptomics data ANalysis with cross-sample transcriptional similarity Guidance), which is capable of performing multi-sample spatial transcriptomics spot cellular deconvolution by allowing both cross-sample expression-based similarity information sharing as well as spatial correlation in gene expression patterns within samples. Experiments on a semi-synthetic spatial transcriptomics dataset and three real-world spatial transcriptomics datasets demonstrate the effectiveness of MUSTANG in revealing biological insights inherent in the cellular characterization of tissue samples under study.

A Bioinformatic Analysis Of T-Cell Epitope Diversity In Sars-Cov-2 Variants: Association With Covid-19 Clinical Severity In The United States Population, Grace J. Kim, Jacob H. Elnaggar, Mallory Varnado, Amy K. Feehan, Darlene Tauzier, Rebecca Rose, Susanna L. Lamers, Maya Sevalia, Najah Nicholas, Elizabeth Gravois, Daniel Fort, Judy S. Crabtree, Lucio Miele

School of Graduate Studies Faculty Publications

Long-term immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requires the identification of T-cell epitopes affecting host immunogenicity. In this computational study, we explored the CD8+ epitope diversity estimated in 27 of the most common HLA-A and HLA-B alleles, representing most of the United States population. Analysis of 16 SARS-CoV-2 variants [B.1, Alpha (B.1.1.7), five Delta (AY.100, AY.25, AY.3, AY.3.1, AY.44), and nine Omicron (BA.1, BA.1.1, BA.2, BA.4, BA.5, BQ.1, BQ.1.1, XBB.1, XBB.1.5)] in analyzed MHC class I alleles revealed that SARS-CoV-2 CD8+ epitope conservation was estimated at 87.6%–96.5% in spike (S), 92.5%–99.6% in membrane (M), and 94.6%–99% in …

Optimization Of The Antifungal Properties Of The Bacterial Peptide Entv By Variant Analysis, Shantanu Guha, Shane A Cristy, Giuseppe Buda De Cesare, Melissa R Cruz, Michael C Lorenz, Danielle A Garsin

Faculty, Staff and Student Publications

Fungal resistance to commonly used medicines is a growing public health threat, and there is a dire need to develop new classes of antifungals. We previously described a peptide produced by Enterococcus faecalis, EntV, that restricts Candida albicans to a benign form rather than having direct fungicidal activity. Moreover, we showed that one 12-amino acid (aa) alpha helix of this peptide retained full activity, with partial activity down to the 10aa alpha helix. Using these peptides as a starting point, the current investigation sought to identify the critical features necessary for antifungal activity and to screen for new variants …

Progress Toward A Vaccine For Extraintestinal Pathogenic Coli (Expec) Ii: Efficacy Of A Toxin-Autotransporter Dual Antigen Approach, Yikun Xing, Justin R Clark, James D Chang, Jacob J Zulk, Dylan M Chirman, Felipe-Andres Piedra, Ellen E Vaughan, Haroldo J Hernandez Santos, Kathryn A Patras, Anthony W Maresso

Faculty, Staff and Students Publications

Extraintestinal pathogenic Escherichia coli (ExPEC) is a leading cause of worldwide morbidity and mortality, the top cause of antimicrobial-resistant (AMR) infections, and the most frequent cause of life-threatening sepsis and urinary tract infections (UTI) in adults. The development of an effective and universal vaccine is complicated by this pathogen’s pan-genome, its ability to mix and match virulence factors and AMR genes via horizontal gene transfer, an inability to decipher commensal from pathogens, and its intimate association and co-evolution with mammals. Using a pan virulome analysis of >20,000 sequenced E. coli strains, we identified the secreted cytolysin α-hemolysin (HlyA) as a …

Serine Deamination By Human Serine Racemase Synergizes With Antibiotics To Curtail The Replication Of Chlamydia Trachomatis, Patricia D. Mott, Arnold H. Zea, Jamiya Lewis, Oygul Mirzalieva, Ashok A. Aiyar

School of Medicine Faculty Publications

The obligate intracellular bacterium, Chlamydia trachomatis, has evolved to depend on its human host for many metabolites, including most amino acids and three of the four nucleotides. Given this, it is not surprising that depletion of a single amino acid in the host cell growth medium blocks chlamydial replication. Paradoxically, supra-normal levels of some amino acids also block productive replication of Chlamydia. Here, we have determined how elevated serine levels, generated by exogenous supplementation, impede chlamydial inclusion development and reduce the generation of infectious progeny. Our findings reveal that human serine racemase, which is broadly expressed in multiple tissues, potentiates …

Autologous Bone Marrow Mononuclear Cells To Treat Severe Traumatic Brain Injury In Children, Charles S Cox, David M Notrica, Jenifer Juranek, Jeffrey H Miller, Fabio Triolo, Steven Kosmach, Sean I Savitz, P David Adelson, Claudia Pedroza, Scott D Olson, Michael C Scott, Akshita Kumar, Benjamin M Aertker, Henry W Caplan, Margaret L Jackson, Brijesh S Gill, Robert A Hetz, Michael S Lavoie, Linda Ewing-Cobbs

Faculty, Staff and Student Publications

Autologous bone marrow mononuclear cells (BMMNCs) infused after severe traumatic brain injury have shown promise for treating the injury. We evaluated their impact in children, particularly their hypothesized ability to preserve the blood–brain barrier and diminish neuroinflammation, leading to structural CNS preservation with improved outcomes.

We performed a randomized, double-blind, placebo-sham-controlled Bayesian dose-escalation clinical trial at two children's hospitals in Houston, TX and Phoenix, AZ, USA (NCT01851083). Patients 5–17 years of age with severe traumatic brain injury (Glasgow Coma Scale score ≤ 8) were randomized to BMMNC or placebo (3:2). Bone marrow harvest, cell isolation and infusion were …

Sialic Acid-Siglec-E Interactions Regulate The Response Of Neonatal Macrophages To Group B Streptococcus, Sean J Lund, Pamela G B Del Rosario, Asami Honda, Kaitlin J Caoili, Marten A Hoeksema, Victor Nizet, Kathryn A Patras, Lawrence S Prince

Faculty, Staff and Students Publications

The mammalian Siglec receptor sialoadhesin (Siglec1, CD169) confers innate immunity against the encapsulated pathogen group B Streptococcus (GBS). Newborn lung macrophages have lower expression levels of sialoadhesin at birth compared with the postnatal period, increasing their susceptibility to GBS infection. In this study, we investigate the mechanisms regulating sialoadhesin expression in the newborn mouse lung. In both neonatal and adult mice, GBS lung infection reduced Siglec1 expression, potentially delaying acquisition of immunity in neonates. Suppression of Siglec1 expression required interactions between sialic acid on the GBS capsule and the inhibitory host receptor Siglec-E. The Siglec1 gene contains multiple STAT binding …

Performance Of A Stool-Based Quantitative Pcr Assay For The Diagnosis Of Tuberculosis In Adolescents And Adults: A Multinational, Prospective Diagnostic Accuracy Study, Alexander Kay, Anca Vasiliu, Lucia Carratala-Castro, Bariki Mtafya, Jose Euberto Mendez Reyes, Nontobeko Maphalala, Shilzia Munguambe, Durbbin Mulengwa, Tara Ness, Belen Saavedra, Jason Bacha, Gugu Maphalala, Rojelio Mejia, Godwin Mtetwa, Sozinho Acacio, Patricia Manjate, Edson Mambuque, Nosisa Shiba, Nokwanda Kota, Mangaliso Ziyane, Nyanda Elias Ntinginya, Christoph Lange, H Lester Kirchner, Andrew R Dinardo, Alberto L Garcia-Basteiro, Anna Maria Mandalakas, Stool4tb Global Partnership

Faculty, Staff and Students Publications

BACKGROUND: Despite increasing availability of rapid molecular tests for the diagnosis of tuberculosis in high-burden settings, many people with tuberculosis are undiagnosed. Reliance on sputum as the primary specimen for tuberculosis diagnostics contributes to this diagnostic gap. We evaluated the diagnostic accuracy and additive yield of a novel stool quantitative PCR (qPCR) assay for the diagnosis of tuberculosis in three countries in Africa with high tuberculosis burdens.

METHODS: We undertook a prospective diagnostic accuracy study in Eswatini, Mozambique, and Tanzania from Sept 21, 2020, to Feb 2, 2023, to compare the diagnostic accuracy for tuberculosis of a novel stool qPCR …

Investigating The Role Of The Gut Microbiota On Immune Checkpoint Inhibitor-Mediated Colitis, Taylor Halsey, Robert Jenq

Dissertations and Theses (Open Access)

Immune checkpoint inhibitors (ICIs) have been revolutionary in the fight against cancer by recruiting the host immune system as an agent for attack on malignant cells. Unfortunately, immune-related adverse events (irAEs), including ICI-mediated colitis (IMC), are common side effects that result from immune cell mediated damage on healthy tissues. Recent studies have highlighted a role for the gut microbiota in modulating ICI-mediated anti-tumor responses, but less is known regarding how the gut microbiota may impact on irAEs. Considering that the gastrointestinal tract harbors thousands of unique microbial species, many of which are known to modulate the immune system, microbes and …

Molecular Basis Of Cell Membrane Adaption Against Daptomycin In Enterococcus Faecalis, April Nguyen

Dissertations and Theses (Open Access)

Daptomycin is a last-resort lipopeptide antibiotic that disrupts cell membrane (CM) and peptidoglycan homeostasis (Grein et al., 2020a; Müller et al., 2016a). Enterococcus faecalis has developed a sophisticated mechanism to avoid daptomycin killing by redistributing CM anionic phospholipids away from the septum. The CM changes are orchestrated by a three-component regulatory system, designated LiaFSR, with a possible contribution of cardiolipin synthase (Cls) (Cesar A Arias et al., 2011a; Khan et al., 2019b; Palmer et al., 2011a; Panesso et al., 2015a; Reyes et al., 2015a). However, the mechanism by which LiaFSR controls the cell membrane response and the role of Cls …

Mir4435-2hg As A Possible Novel Predictive Biomarker Of Chemotherapy Response And Death In Pediatric B-Cell All, Yulieth Torres-Llanos, Jovanny Zabaleta, Nataly Cruz-Rodriguez, Sandra Quijano, Paula Carolina Guzmán, Iliana De Los Reyes, Nathaly Poveda-Garavito, Ana Infante, Liliana Lopez-Kleine, Alba Lucía Combita

School of Medicine Faculty Publications

Introduction: Although B-cell acute lymphoblastic leukemia (B-cell ALL) survival rates have improved in recent years, Hispanic children continue to have poorer survival rates. There are few tools available to identify at the time of diagnosis whether the patient will respond to induction therapy. Our goal was to identify predictive biomarkers of treatment response, which could also serve as prognostic biomarkers of death, by identifying methylated and differentially expressed genes between patients with positive minimal residual disease (MRD+) and negative minimal residual disease (MRD-). Methods: DNA and RNA were extracted from tumor blasts separated by immunomagnetic columns. Illumina MethlationEPIC and mRNA …

Study On A Strong Polymer Gel By The Addition Of Micron Graphite Oxide Powder And Its Plugging Of Fracture, Bin Shi, Guangming Zhang, Lei Zhang, Chengjun Wang, Zhonghui Li, Fangping Chen

Faculty, Staff and Student Publications

It is difficult to plug the fracture water channeling of a fractured low-permeability reservoir during water flooding by using the conventional acrylamide polymer gel due to its weak mechanical properties. For this problem, micron graphite powder is added to enhance the comprehensive properties of the acrylamide polymer gel, which can improve the plugging effect of fracture water channeling. The chemical principle of this process is that the hydroxyl and carboxyl groups of the layered micron graphite powder can undergo physicochemical interactions with the amide groups of the polyacrylamide molecule chain. As a rigid structure, the graphite powder can support the …

Quorum-Sensing Agr System Of Staphylococcus Aureus Primes Gene Expression For Protection From Lethal Oxidative Stress, Magdalena Podkowik, Andrew I Perault, Gregory Putzel, Andrew Pountain, Jisun Kim, Ashley L Dumont, Erin E Zwack, Robert J Ulrich, Theodora K Karagounis, Chunyi Zhou, Andreas F Haag, Julia Shenderovich, Gregory A Wasserman, Junbeom Kwon, John Chen, Anthony R Richardson, Jeffrey N Weiser, Carla R Nowosad, Desmond S Lun, Dane Parker, Alejandro Pironti, Xilin Zhao, Karl Drlica, Itai Yanai, Victor J Torres, Bo Shopsin

Faculty, Staff and Student Publications

The agr quorum-sensing system links Staphylococcus aureus metabolism to virulence, in part by increasing bacterial survival during exposure to lethal concentrations of H2O2, a crucial host defense against S. aureus. We now report that protection by agr surprisingly extends beyond post-exponential growth to the exit from stationary phase when the agr system is no longer turned on. Thus, agr can be considered a constitutive protective factor. Deletion of agr resulted in decreased ATP levels and growth, despite increased rates of respiration or fermentation at appropriate oxygen tensions, suggesting that Δagr cells undergo a shift towards a hyperactive metabolic …

Histone Proteoform Analysis Reveals Epigenetic Changes In Adult Mouse Brown Adipose Tissue In Response To Cold Stress, Bethany C Taylor, Loic H Steinthal, Michelle Dias, Hari Krishna Yalamanchili, Scott A Ochsner, Gladys E Zapata, Nitesh R Mehta, Neil J Mckenna, Nicolas L Young, Alli M Nuotio-Antar

Faculty, Staff and Students Publications

BACKGROUND: Regulation of the thermogenic response by brown adipose tissue (BAT) is an important component of energy homeostasis with implications for the treatment of obesity and diabetes. Our preliminary analyses of RNA-Seq data uncovered many nodes representing epigenetic modifiers that are altered in BAT in response to chronic thermogenic activation. Thus, we hypothesized that chronic thermogenic activation broadly alters epigenetic modifications of DNA and histones in BAT.

RESULTS: Motivated to understand how BAT function is regulated epigenetically, we developed a novel method for the first-ever unbiased top-down proteomic quantitation of histone modifications in BAT and validated our results with a …