Medical Microbiology Commons^™

Identification Of Serum Mirna Signature And Establishment Of A Nomogram For Risk Stratification In Patients With Pancreatic Ductal Adenocarcinoma, Raju Kandimalla, Tadanobu Shimura, Saurav Mallik, Fuminori Sonohara, Susan Tsai, Douglas B Evans, Song Cheol Kim, Hideo Baba, Yasuhiro Kodera, Daniel Von Hoff, Xi Chen, Ajay Goel

Faculty, Staff and Students Publications

OBJECTIVE: The aim of the study was to perform mRNA-miRNA regulatory network analyses to identify a miRNA panel for molecular subtype identification and stratification of high-risk patients with pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND: Recent transcriptional profiling effort in PDAC has led to the identification of molecular subtypes that associate with poor survival; however, their clinical significance for risk stratification in patients with PDAC has been challenging.

METHODS: By performing a systematic analysis in The Cancer Genome Atlas and International Cancer Genome Consortium cohorts, we discovered a panel of miRNAs that associated with squamous and other poor molecular subtypes in PDAC. …

Endometriosis-Associated Angiogenesis And Anti-Angiogenic Therapy For Endometriosis, Monica S Chung, Sang Jun Han

Faculty, Staff and Students Publications

Endometriosis is a known estrogen-dependent inflammatory disease affecting reproductive-aged women. Common symptoms include pelvic pain, dysmenorrhea, dyspareunia, heavy menstrual bleeding, and infertility. The exact etiology of endometriosis is largely unknown, and, thus, the diagnosis and treatment of endometriosis are challenging. A complex interplay of many molecular mechanisms is thought to aid in the progression of endometriosis, most notably angiogenesis. This mini-review examines our current knowledge of the molecular etiology of endometriosis-associated angiogenesis and discusses anti-angiogenic therapy, in the blockade of endometriosis-associated angiogenesis, as potential non-hormonal therapy for the treatment of endometriosis.

Common Genomic Aberrations In Mouse And Human Breast Cancers With Concurrent P53 Deficiency And Activated Pten-Pi3k-Akt Pathway, Jarrod D Martinez, Qianxing Mo, Yixiang Xu, Li Qin, Yi Li, Jianming Xu

Faculty, Staff and Students Publications

Simultaneous P53 loss and activation of the PTEN-restricted PI3K-AKT pathway frequently occur in aggressive breast cancers. P53 loss causes genome instability, while PTEN loss and/or activating mutations of PIK3CA and AKT promote cancer cell proliferation that also increases incidences of genomic aberrations. However, the genomic alterations associated with P53 loss and activated PTEN-PI3K-AKT signaling in breast cancer have not been defined. Spatiotemporally controlled breast cancer models with inactivation of both P53 and Pten in adult mice have not been established for studying genomic alterations. Herein, we deleted both floxed Pten and Tp53 genes in the mammary gland epithelial cells in …

Nuclear Progesterone Receptor Expressed By The Cortical Thymic Epithelial Cells Dictates Thymus Involution In Murine Pregnancy, Soo Hyun Ahn, Sean L Nguyen, Tae Hoon Kim, Jae-Wook Jeong, Ripla Arora, John P Lydon, Margaret G Petroff

Faculty, Staff and Students Publications

Progesterone is a gonadal pro-gestational hormone that is absolutely necessary for the success of pregnancy. Most notable actions of progesterone are observed in the female reproductive organs, the uterus and the ovary. Acting through the nuclear progesterone receptor (PGR), progesterone prepares the endometrium for implantation of the embryo. Interestingly, the maternal thymus also is a known expressor of Pgr; its absence is associated with murine pregnancy complications. However, the localization of its expression and its functional importance were not known. Here, we used a transgenic dual fluorescent reporter mouse model and genetic deletion of Pgr in Foxn1+ thymic epithelial …

Interleukin-1Β Secretion Induced By Mucosa-Associated Gut Commensal Bacteria Promotes Intestinal Barrier Repair, Wan-Jung H Wu, Myunghoo Kim, Lin-Chun Chang, Adrien Assie, Fatima B Saldana-Morales, Daniel F Zegarra-Ruiz, Kendra Norwood, Buck S Samuel, Gretchen E Diehl

Faculty, Staff and Students Publications

The gut microbiota is essential for maintenance and repair of the intestinal epithelial barrier. As shifts in both intestinal epithelial barrier function and microbiota composition are found in inflammatory bowel disease patients, it is critical to understand the role of distinct bacteria in regulating barrier repair. We identified a mouse commensal E. coli isolate, GDAR2-2, that protects mice from Citrobacter rodentium infection and dextran sulfate sodium-induced colitis. Colonization with GDAR2-2 in mice resulted in expansion of CX3CR1+ mononuclear phagocytes, including CX3CR1+ macrophages/dendritic cells and monocytes, along with IL-22-secreting type 3 innate lymphoid cells and improved epithelial barrier function. In vitro …

An Investigation Into The Prevalence Of Vancomycin-Resistant Enterococci Within An Irish Hospital, Dylan Casey

International Undergraduate Journal of Health Sciences

Vancomycin-resistant enterococci (VRE) are well-recognised nosocomial pathogens that pose a significant threat to public health. Associated with poorer clinical outcomes than their vancomycin-sensitive counterparts, the prevalence of VRE in Ireland has increased in recent times, with the European Antimicrobial Resistance Surveillance Network reporting that out of 29 countries, Ireland demonstrated the highest rates of vancomycin resistance among invasive Enterococcus faecium isolates between 2011 and 2014 (2011; 34.9%, 2012; 44.0%, 2013; 42.7%, 2014; 45.1%). Herein, we investigate VRE prevalence in the Mercy University Hospital (MUH) – an acute care hospital in southern Ireland. A total of 21 first-time VRE infections were …

Eliminating Contamination In Umbilical Cord Blood Culture Sampling For Early-Onset Neonatal Sepsis., Vilmaris Quinones Cardona, Vanessa Lowery, David Cooperberg, Endla K Anday, Alison J Carey

Department of Pediatrics Faculty Papers

Introduction: Despite the advantages of umbilical cord blood culture (UCBC) use for diagnosis of early onset sepsis (EOS), contamination rates have deterred neonatologists from its widespread use. We aimed to implement UCBC collection in a level III neonatal intensive care unit (NICU) and apply quality improvement (QI) methods to reduce contamination in the diagnosis of early onset sepsis. Methods: Single-center implementation study utilizing quality improvement methodology to achieve 0% contamination rate in UCBC samples using the Plan-Do-Study-Act (PDSA) model for improvement. UCBC was obtained in conjunction with peripheral blood cultures (PBC) in neonates admitted to the NICU due to maternal …

The Mrna-Lnp Platform's Lipid Nanoparticle Component Used In Preclinical Vaccine Studies Is Highly Inflammatory, Sonia Ndeupen, Zhen Qin, Sonya Jacobsen, Aurélie Bouteau, Henri Estanbouli, Botond Z. Igyártó

Department of Microbiology and Immunology Faculty Papers

Vaccines based on mRNA-containing lipid nanoparticles (LNPs) are a promising new platform used by two leading vaccines against COVID-19. Clinical trials and ongoing vaccinations present with varying degrees of protection levels and side effects. However, the drivers of the reported side effects remain poorly defined. Here we present evidence that Acuitas' LNPs used in preclinical nucleoside-modified mRNA vaccine studies are highly inflammatory in mice. Intradermal and intramuscular injection of these LNPs led to rapid and robust inflammatory responses, characterized by massive neutrophil infiltration, activation of diverse inflammatory pathways, and production of various inflammatory cytokines and chemokines. The same dose of …

Evaluation Of Stratified Antibiograms For Use In Laboratory And Antimicrobial Stewardship, Linsey Donner

Theses & Dissertations

Antibiograms are critical for choosing empiric antimicrobial therapy. Cumulative antibiograms, which aggregate susceptibility data, can mask differences within specific patient subsets or clinical syndromes. This dissertation was done to determine if antibiotic susceptibilities showed substantial differences when comparing stratified antibiograms to cumulative antibiograms.

Antibiotic susceptibility data was retrospectively obtained from Nebraska Medicine January 1, 2017 – December 31, 2019 for Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis. The University of Nebraska Medical Center’s web antibiogram clinical decision support tool was used to export the data. Bacteria-antibiotic susceptibility rates of stratified antibiograms …

Characterizing And Overcoming Resistance To Aminomethylspectinomycins In Gram-Negative Bacteria, Nisha Das

Theses and Dissertations (ETD)

Spectinomycin (SPC) is a broad-spectrum aminocyclitol antibiotic. Its use in agriculture has led to widespread resistance in enteric bacteria, necessitating the development of more effective analogs. Aminomethyl spectinomycins (amSPC) are modified spectinomycins with increased potency against many bacterial species. These species include Legionella pneumophila, which harbors a chromosomally encoded aminoglycoside modifying enzyme (AME). In this study, we follow up on this observation and examine the extent to which the amSPCs are substrates for AMEs through adenylation (ANTs) and phosphorylation (APH). APH(9)-Ia and ANT(3")(9) were expressed in E. coli BL21(DE3) and purified using the Ni-affinity chromatography. The ability of AMEs to …

Genital Chlamydia Infection Is Influenced By The Female Sex Hormones Estrogen And Progesterone In Vivo, Amy Gail Gravitte

Electronic Theses and Dissertations

Chlamydia is the most common bacterial sexually transmitted infection in the United States and worldwide. It often goes unnoticed due to lack of symptoms and left untreated it can ascend the female genital tract to cause sequelae like pelvic inflammatory disease and irreversible tubal infertility. In reproductive-aged women, female sex hormones estrogen (E2) and progesterone (P4) concentrations fluctuate during the menstrual cycle and are influenced by hormonal contraceptives and hormone replacement therapy. E2 and P4 influence genital Chlamydia infection in women and mice, but these multifactorial interactions are not entirely mapped out. The complex interplay of E2 and P4 with …

Sars-Cov-2 Induces Robust Germinal Center Cd4 T Follicular Helper Cell Responses In Rhesus Macaques, Yashavanth Shaan Lakshmanappa, Sonny R. Elizaldi, Jamin W. Roh, Brian A. Schmidt, Timothy D. Carroll, Kourtney D. Weaver, Justin C. Smith, Anil Verma, Jesse D. Deere, Joseph Dutra, Mars Stone, Sergej Franz, Rebecca Lee Sammak, Katherine J. Olstad, J. Rachel Reader, Zhong Min Ma, Nancy K. Nguyen, Jennifer Watanabe, Jodie Usachenko, Ramya Immareddy

School of Graduate Studies Faculty Publications

CD4 T follicular helper (Tfh) cells are important for the generation of durable and specific humoral protection against viral infections. The degree to which SARS-CoV-2 infection generates Tfh cells and stimulates the germinal center (GC) response is an important question as we investigate vaccine induced immunity against COVID-19. Here, we report that SARS-CoV-2 infection in rhesus macaques, either infused with convalescent plasma, normal plasma, or receiving no infusion, resulted in transient accumulation of pro-inflammatory monocytes and proliferating Tfh cells with a Th1 profile in peripheral blood. CD4 helper cell responses skewed predominantly toward a Th1 response in blood, lung, and …

Moerv29 Promotes Apoplastic Effector Secretion Contributing To Virulence Of The Rice Blast Fungus Magnaporthe Oryzae, Bin Qian, Xiaotong Su, Ziyuan Ye, Xinyu Liu, Muxing Liu, Danyu Shen, Han Chen, Haifeng Zhang, Ping Wang, Zhengguang Zhang

School of Medicine Faculty Publications

During plant-pathogenic fungi and host plants interactions, numerous pathogen-derived proteins are secreted resulting in the activation of the unfolded protein response (UPR) pathway. For efficient trafficking of secretory proteins, including those important in disease progression, the cytoplasmic coat protein complex II (COPII) exhibits a multifunctional role whose elucidation remains limited. Here, we discovered that the COPII cargo receptor MoErv29 functions as a target of MoHac1, a previously identified transcription factor of the UPR pathway. In Magnaporthe oryzae, deletion of MoERV29 severely affected the vegetative growth, conidiation and biotrophic invasion of the fungus in susceptible rice hosts. We demonstrated that MoErv29 …

Lysergic Acid Diethylamide Induces Increased Signalling Entropy In Rats’ Prefrontal Cortex, Aurora Savino, Charles D. Nichols

School of Graduate Studies Faculty Publications

Psychedelic drugs are gaining attention from the scientific community as potential new compounds for the treatment of psychiatric diseases such as mood and substance use disorders. The 5-HT2A receptor has been identified as the main molecular target, and early studies pointed to an effect on the expression of neuroplasticity genes. Analysing RNA-seq data from the prefrontal cortex of rats chronically treated with lysergic acid diethylamide (LSD), we describe the psychedelic-induced rewiring of gene co-expression networks, which become less centralised but more complex, with an overall increase in signalling entropy typical of highly plastic systems. Intriguingly, signalling entropy mirrors, at the …

A Strategy To Detect Emerging Non-Delta Sars-Cov-2 Variants With A Monoclonal Antibody Specific For The N501 Spike Residue, Rama Devudu Puligedda, Fetweh H Al-Saleem, Christoph Wirblich, Chandana Devi Kattala, Marko Jović, Laura Geiszler, Himani Devabhaktuni, Giora Z Feuerstein, Matthias J. Schnell, Markus Sack, Lawrence L Livornese, Scott K Dessain

Department of Microbiology and Immunology Faculty Papers

Efforts to control SARS-CoV-2 have been challenged by the emergence of variant strains that have important implications for clinical and epidemiological decision making. Four variants of concern (VOCs) have been designated by the Centers for Disease Control and Prevention (CDC), namely, B.1.617.2 (delta), B.1.1.7 (alpha), B.1.351 (beta), and P.1 (gamma), although the last three have been downgraded to variants being monitored (VBMs). VOCs and VBMs have shown increased transmissibility and/or disease severity, resistance to convalescent SARS-CoV-2 immunity and antibody therapeutics, and the potential to evade diagnostic detection. Methods are needed for point-of-care (POC) testing to rapidly identify these variants, protect …

Mapk6-Akt Signaling Promotes Tumor Growth And Resistance To Mtor Kinase Blockade, Qinbo Cai, Wolong Zhou, Wei Wang, Bingning Dong, Dong Han, Tao Shen, Chad J Creighton, David D Moore, Feng Yang

Faculty, Staff and Students Publications

Mitogen-activated protein kinase 6 (MAPK6) is an atypical MAPK. Its function in regulating cancer growth remains elusive. Here, we reported that MAPK6 directly activated AKT and induced oncogenic outcomes. MAPK6 interacted with AKT through its C34 region and the C-terminal tail and phosphorylated AKT at S473 independent of mTORC2, the major S473 kinase. mTOR kinase inhibitors have not made notable progress in the clinic. Our identified MAPK6-AKT axis may provide a major resistance pathway. Besides repressing growth, inhibiting MAPK6 sensitized cancer cells to mTOR kinase inhibitors. MAPK6 overexpression is associated with decreased overall survival and the survival of patients with …

Cancer Vaccines And Immunotherapy For Tumor Prevention And Treatment, Jagmohan Singh, Wilbur Bowne, Adam E. Snook

Kimmel Cancer Center Faculty Papers

In this editorial, we highlight articles published in this Special Issue of Vaccines on "Cancer Vaccines and Immunotherapy for Tumor Prevention and Treatment", recent developments in the field of cancer vaccines, and the potential for immunotherapeutic combinations in cancer care. This issue covers important developments and progress being made in the cancer vaccine field and possible future directions for exploring new technologies to produce optimal immune responses against cancer and expand the arena of prophylactic and therapeutic cancer vaccines for the treatment of this deadly disease.

The Sulfur Microbial Diet Is Associated With Increased Risk Of Early-Onset Colorectal Cancer Precursors, Long H. Nguyen, Yin Cao, Jinhee Hur, Raaj S. Mehta, Daniel R. Sikavi, Yiqing Wang, Wenjie Ma, Kana Wu, Mingyang Song, Edward L. Giovannucci, Eric B. Rimm, Walter C. Willett, Wendy S. Garrett, Jacques Izard, Curtis Huttenhower, Andrew T. Chan

Food for Health: Publications

Background and aims: Diet may contribute to the increasing incidence of colorectal cancer (CRC) before age 50 (early-onset CRC). Microbial metabolism of dietary sulfur produces hydrogen sulfide (H₂S), a gastrointestinal carcinogen that cannot be easily measured at scale. As a result, evidence supporting its role in early neoplasia is lacking.

Methods: We evaluated long-term adherence to the sulfur microbial diet, a dietary index defined a priori based on increased abundance of 43 bacterial species involved with sulfur metabolism, with risk of CRC precursors among 59,013 individuals who underwent lower endoscopy in the Nurses’ Health Study II …

Interleukin-10 Suppression Enhances T-Cell Antitumor Immunity And Responses To Checkpoint Blockade In Chronic Lymphocytic Leukemia., J R Rivas, Y Liu, S S Alhakeem, J M Eckenrode, F Marti, J P Collard, Y Zhang, K A Shaaban, N Muthusamy, G C Hildebrandt, L Chen, J S Thorson, M Leggas, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

T-cell dysfunction is a hallmark of B-cell Chronic Lymphocytic Leukemia (CLL), where CLL cells downregulate T-cell responses through regulatory molecules including programmed death ligand-1 (PD-L1) and Interleukin-10 (IL-10). Immune checkpoint blockade (ICB) aims to restore T-cell function by preventing the ligation of inhibitory receptors like PD-1. However, most CLL patients do not respond well to this therapy. Thus, we investigated whether IL-10 suppression could enhance antitumor T-cell activity and responses to ICB. Since CLL IL-10 expression depends on Sp1, we utilized a novel, better tolerated analogue of the Sp1 inhibitor mithramycin (MTM

The Role Of The Filifactor Alocis Hypothetical Protein Fa519 In Oxidative Stress Resistance, Ezinne Rebecca Aja

Loma Linda University Electronic Theses, Dissertations & Projects

Filifactor alocis, a fastidious, Gram-positive, obligate anaerobic bacterium, is a newly appreciated member of the periodontal community, which is now proposed to be a diagnostic indicator of periodontal disease. Its pathogenic characteristics are highlighted by its ability to survive in the oxidative-stress rich environment of the periodontal pocket and to significantly alter the microbial community dynamics by forming biofilms and interacting with several oral bacteria. Currently, there is incomplete information on the pathogenic mechanism(s) and a possible dynamic functional role of F. alocis in the dysbiotic microbial community. Because the stress response of this bacterium to the oxidative environment …