Microbiology Commons^™

Two Sampling Methods Yield Distinct Microbial Signatures In The Nasopharynges Of Asthmatic Children., Marcos Pérez-Losada, Keith A. Crandall, Robert J. Freishtat

Pediatrics Faculty Publications

Background

The nasopharynx is a reservoir for pathogens associated with respiratory illnesses, such as asthma. Next-generation sequencing (NGS) has been used to characterize the nasopharyngeal microbiome during health and disease. Most studies so far have surveyed the nasopharynx as a whole; however, less is known about spatial variation (biogeography) in nasal microenvironments and how sampling techniques may capture that microbial diversity.

Findings

We used targeted 16S rRNA MiSeq sequencing and two different sampling strategies [nasal washes (NW) and nasal brushes (NB)] to characterize the nasopharyngeal microbiota in 30 asthmatic children. Nasal brushing is more abrasive than nasal washing and targeted …

Cold Atmospheric Plasma Inhibits Hiv-1 Replication In Macrophages By Targeting Both The Virus And The Cells., Olga Volotskova, Larisa Dubrovsky, Michael Keidar, Michael Bukrinsky

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Cold atmospheric plasma (CAP) is a specific type of partially ionized gas that is less than 104°F at the point of application. It was recently shown that CAP can be used for decontamination and sterilization, as well as anti-cancer treatment. Here, we investigated the effects of CAP on HIV-1 replication in monocyte-derived macrophages (MDM). We demonstrate that pre-treatment of MDM with CAP reduced levels of CD4 and CCR5, inhibiting virus-cell fusion, viral reverse transcription and integration. In addition, CAP pre-treatment affected cellular factors required for post-entry events, as replication of VSV-G-pseudotyped HIV-1, which by-passes HIV receptor-mediated fusion at the plasma …

First Described Case Of Group B Streptococcus Pelvic Abscess In A Patient With No Medical Comorbidities, Paul Tyan, Elias Abi-Khalil, Karthik Dwarki, Gaby N. Moawad

Obstetrics and Gynecology Faculty Publications

Background. Group B Streptococcus is an organism that commonly infects a wide range of hosts including infants in the first week of life, pregnant women, and older age adults as well as adults with underlying medical comorbidities.

Case. Large pelvic abscess in a nonpregnant patient found to be caused by Group B Streptococcuswas treated successfully with IR guided drainage and antibiotics.

Conclusion. Though rare, GBS can still be a cause of invasive infection even in individuals who are nonpregnant and have no underlying comorbidities. Empiric antibiotic coverage for this organism should be kept in mind when treating an abscess.

Circulating Fibroblast Growth Factor-2, Hiv-Tat, And Vascular Endothelial Cell Growth Factor-A In Hiv-Infected Children With Renal Disease Activate Rho-A And Src In Cultured Renal Endothelial Cells., Jharna R Das, J Silvio Gutkind, Patricio E. Ray

Pediatrics Faculty Publications

Renal endothelial cells (REc) are the first target of HIV-1 in the kidney. The integrity of REc is maintained at least partially by heparin binding growth factors that bind to heparan sulfate proteoglycans located on their cell surface. However, previous studies showed that the accumulation of two heparin-binding growth factors, Vascular Endothelial Cell Growth Factor-A (VEGF-A) and Fibroblast Growth Factor-2 (FGF-2), in combination with the viral protein Tat, can precipitate the progression of HIV-renal diseases. Nonetheless, very little is known about how these factors affect the behavior of REc in HIV+ children. We carried out this study to determine how …

Utility And Origin Of Blood-Based Autoantibodies For Early Detection And Diagnosis Of Neurodegenerative Diseases, Cassandra Demarshall

Graduate School of Biomedical Sciences Theses and Dissertations

Autoantibodies are self-reactive antibodies that have been widely implicated as causal agents of autoimmune diseases. They are found in the blood of all human sera, regardless of age, gender, or the presence or absence of disease. While the underlying reason for their ubiquity remains unknown, it has been hypothesized that they participate in the clearance of blood-borne cell and tissue debris generated in both healthy and diseased individuals on a daily basis. Although much evidence supports this debris clearance role, recent studies also suggest a causal role for autoantibodies in disease. My thesis work has focused on this "cause and/or …

Lineage-Specific Differences In The Gp120 Inner Domain Layer 3 Of Human And Simian Immunodeficiency Viruses, Shilei Ding, Halima Medjahed, Jérémie Prévost, Mathieu Coutu, Shi-Hua Xiang, Andrés Finzi

Nebraska Center for Virology: Faculty Publications

Binding of HIV-1 and SIV gp120 exterior envelope glycoprotein to CD4 triggers conformational changes in gp120 that promote its interaction with one of the chemokine receptors, usually CCR5, ultimately leading to gp41-mediated virus-cell membrane fusion and entry. We previously described that topological Layers (Layer 1, Layer 2 and Layer 3) in the gp120 inner domain contribute to gp120-trimer association in the unliganded state but also help secure CD4 binding. Relative to Layer 1 of HIV-1 gp120, the SIVmac239 gp120 Layer 1 plays a more prominent role in maintaining gp120-trimer association but is minimally involved in promoting CD4 binding, which could …

Disseminated Cryptococcosis With Endobronchial Lesions, Kusha Davar, Arun Jose, Anne Cramer, Alexander Aldrich, Jillian S. Catalanotti

Medicine Faculty Posters and Presentations

No abstract provided.

Human Herpesvirus Multiplex Ddpcr Detection In Brain Tissue From Low- And High-Grade Astrocytoma Cases And Controls., Cheng-Te Major Lin, Emily C. Leibovitch, M. Isabel Almira-Suarez, Steven Jacobson

Pathology Faculty Publications

BACKGROUND: Glioblastoma (GBM) is a fatal CNS malignancy, representing 50 % of all gliomas with approximately 12-18 months survival time after initial diagnosis. Recently, the human herpesvirus cytomegalovirus (CMV) has been suggested to have an oncogenic role, yet this association remains controversial. In addition, human herpesvirus 6 (HHV-6) and Epstein-Barr virus (EBV) have also been associated with low-grade gliomas, but few studies have examined HHV-6 and EBV in glioblastomas. Droplet digital PCR (ddPCR) is a highly precise diagnostic tool that enables the absolute quantification of target DNA. This study examines the association between multiple human herpesviruses and astrocytomas.

METHODS: This …

Complete Genome Sequence Of A Ctx-M-15-Producing Escherichia Coli Strain From The H30rx Subclone Of Sequence Type 131 From A Patient With Recurrent Urinary Tract Infections, Closely Related To A Lethal Urosepsis Isolate From The Patient's Sister., Timothy J. Johnson, Maliha Aziz, Cindy M. Liu, Evgeni Sokurenko, Dagmara I. Kisiela, Sandip Paul, Paal S. Andersen, James R. Johnson, Lance B. Price

Environmental and Occupational Health Faculty Publications

We report here the complete genome sequence, including five plasmid sequences, of Escherichia coli sequence type 131 (ST131) strain JJ1887. The strain was isolated in 2007 in the United States from a patient with recurrent cystitis, whose caregiver sister died from urosepsis caused by a nearly identical strain.

Aeromonas Hydrophila In Amphibians: Harmless Bystander Or Opportunistic Pathogen, Zachary P. Rivas

Honors Undergraduate Theses

For several decades amphibian populations have been declining. Historically, the bacterium A. hydrophila (Ah) was hypothesized to be the causal factor in amphibian disease and population declines. However, with the discovery of a chytrid fungus, Batrachochytrium dendrobatidis (Bd) in 1998, which was identified on the skin of amphibians during documented mortality events, Ah research became of minor interest as focus shifted to Bd. Recent studies into the immunocompromising abilities of Bd, however, have opened new questions about its relationship with Ah and their combined effects on a host.

In this study, I explore the …

Giant Chloroviruses: Five Easy Questions, James L. Van Etten, David Dunigan

Nebraska Center for Virology: Faculty Publications

Chloroviruses are large, icosahedral, dsDNA-containing viruses that replicate in certain unicellular, chlorella-like green algae [1,2]. They exist in freshwater throughout the world with titers as high as thousands of plaque-forming units (PFU) per ml of indigenous water although titers are typically 1–100 PFU/ml. Titers fluctuate during the year with the highest titers typically occurring in the spring and late fall. Known chlorovirus hosts, which are normally symbionts and are often referred to as zoochlorellae, are associated with either the protozoan Paramecium bursaria (Fig 1A), the coelenterate Hydra viridis, or the heliozoan Acanthocystis turfacea. Zoochlorellae are resistant to viruses …

Genetic Barrier To Direct Acting Antivirals In Hcv Sequences Deposited In The European Databank, Dimas Alexandre Kliemann, Cristiane Valle Tovo, Ana Beatriz Gorini Da Veiga, André Luiz Machado, John T. West

Nebraska Center for Virology: Faculty Publications

Background & Aims: Development of resistance results from mutations in the viral genome, and the presence of selective drug pressure leads to the emergence of a resistant virus population. The aim of this study was to analyze the impact of genetic variability on the genetic barrier to drug resistance to DAAs.

Methods: The genetic barrier was quantified based on the number and type of nucleotide mutations required to impart resistance, considering full-length HCV NS3, NS5A and NS5B regions segregated by genotype into subtypes 1a, 1b, 2a, 2b and 3a. This study analyzed 789 NS3 sequences, 708 sequences and 536 NS5B …

Kaposi’S Sarcoma-Associated Herpesvirus Reduces Cellular Myeloid Differentiation Primary-Response Gene 88 (Myd88) Expression Via Modulation Of Its Rna, Amy Lingel, Erica Ehlers, Qianli Wang, Mingxia Cao, Charles Wood, Rongtuan Lin, Luwen Zhang

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma (KS)-associated herpesvirus (KSHV) is a human gammaherpesvirus associated with several human malignancies. The replication and transcription activator (RTA) is necessary and sufficient for the switch from KSHV latency to lytic replication. Interleukin 1 (IL-1) is a major mediator for inflammation and plays an important role in both innate and adaptive immunity. Myeloid differentiation primary response gene 88 (MyD88) is an essential adaptor molecule for IL-1 as well as most Toll-like receptor signaling. In this study, we identified a novel mechanism by which KSHV interferes with host inflammation and immunity. KSHV RTA specifically reduces the steady-state protein levels of …

Nf45 And Nf90 Bind Hiv-1 Rna And Modulate Hiv Gene Expression, Yan Li, Michael Belshan

Nebraska Center for Virology: Faculty Publications

A previous proteomic screen in our laboratory identified nuclear factor 45 (NF45) and nuclear factor 90 (NF90) as potential cellular factors involved in human immunodeficiency virus type 1 (HIV-1) replication. Both are RNA binding proteins that regulate gene expression; and NF90 has been shown to regulate the expression of cyclin T1 which is required for Tat-dependent trans-activation of viral gene expression. In this study the roles of NF45 and NF90 in HIV replication were investigated through overexpression studies. Ectopic expression of either factor potentiated HIV infection, gene expression, and virus production. Deletion of the RNA binding domains of NF45 …

Mucosal Vaccination By Adenoviruses Displaying Reovirus Sigma 1, Eric A. Weaver, Zenaido T. Camacho, Matthew L. Hillestad, Catherine M. Crosby, Mallory A. Turner, Adam J. Guenzel, Hind J. Fadel, George T. Mercier, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

We previously developed adenovirus serotype 5 (Ad5) vectors displaying the sigma 1 protein from reovirus as mucosal vaccines. Ad5-sigma retargets to JAM-1 and sialic acid, but had 40-fold reduced gene delivery when compared to Ad5. While weaker at transduction, Ad5-sigma generated stronger T cell responses than Ad5 when used for mucosal immunization. New Ad5- fiber-sigma vectors were generated here by varying the number of fiber β-spiral shaft repeats (R) fused between fiber tail and the sigma. Ad5 virions encoding R3, R14, and R20 chimeras were rescued. Increasing chimera length led to their decreasing encapsidation of these proteins in the virions. …

Development And Characterization Of A Recombinant Orf Virus Vector Expressing The Spike Protein Of Porcine Epidemic Diarrhea Virus, Kyle Hain

Electronic Theses and Dissertations

Orf virus (ORFV), the type member of the genus Parapoxvirus of the family Poxviridae, causes orf or cutaneous pustular dermatitis in sheep and goats. ORFV is a ubiquitous virus capable of re-infecting its hosts multiple times over time. ORFV causes a non-systemic, self-limiting disease which is usually restricted to the skin surrounding the virus entry sites. ORFV has evolved several immunomodulatory proteins (IMPs) that evade and/or modulate host immune responses to infection and contribute to virus virulence and disease pathogenesis. Given biological properties and unique immunomodula tor y properties, ORFV has gained significant attention in recent years for its …

Investigation Of Anaplasma Phagocytophilum And Anaplasma Marginale Adhesin-Host Cell Interactions, Kathryn S. Hebert

Theses and Dissertations

Anaplasma phagocytophilum and A. marginale are the etiologic agents of bovine anaplasmosis and human granulocytic anaplasmosis, respectively. As obligate intracellular pathogens, binding and entry of host cells is a prerequisite for survival. The molecular events associated with these processes are poorly understood. Identifying the adhesins mediating binding, delineating their key functional domains, and determining the molecular determinants to which they bind not only benefits better understanding of Anaplasma spp. pathobiology, but could also benefit the development of novel approaches for protecting against infection. We previously demonstrated that A. phagocytophilum outer membrane protein A (ApOmpA) is critical for bacterial binding and …

Antibody-Mediated Immunity To Vibrio Cholerae At Epithelial Surfaces, Kara Jeanette Levinson

Legacy Theses & Dissertations (2009 - 2024)

Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has an estimated worldwide disease burden in the millions and remains a significant public health threat. Immunity to V. cholerae is primarily antibody-mediated and though V. cholerae colonization evokes a mucosal immune response, it is the secretory IgA (SIgA) antibodies produced against bacterial surface antigens, specifically lipopolysaccharide (LPS) that confer protective immunity. SIgA antibodies are thought to function by inhibiting colonization by cross-linking and agglutination of pathogens, thereby limiting access to the epithelium, a process known as immune exclusion. Recent studies in other enteric pathogens have demonstrated that SIgA …

Recapitulating Cross-Species Transmission Of Sivcpz To Humans Using Humanized-Blt Mice, Zhe Yuan, Guobin Kang, Fangrui Ma, Wuxun Lu, Wenjin Fan, Christine M. Fennessey, Brandon F. Keele, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The origins of HIV-1 have been widely accepted to be the consequence of simian immunodeficiency viruses from wild chimpanzees (SIVcpz) crossing over to humans. However, there has not been any in vivo study of SIVcpz infection of humans. Also, it remains largely unknown why only specific SIVcpz strains have achieved cross-species transmission and what transmission risk might exist for those SIVcpz strains that have not been found to infect humans. Closing this knowledge gap is essential for better understanding cross-species transmission and predicting the likelihood of additional cross-species transmissions of SIV into humans. Here we show hu-BLT mice are susceptible …

High Glucose Induces Reactivation Of Latent Kaposi’S Sarcoma-Associated Herpesvirus, Fengchun Ye, Yan Zeng, Jingfeng Sha, Tiffany Jones, Kurt Kuhne, Charles Wood, Shou-Jiang Gao

Nebraska Center for Virology: Faculty Publications

High prevalence of Kaposi’s sarcoma (KS) is seen in diabetic patients. It is unknown if the physiological condition of diabetes contributes to KS development. We found elevated levels of viral lytic gene expression when Kaposi’s sarcoma-associated herpesvirus (KSHV) infected cells were cultured in high glucose medium. To demonstrate the association between high glucose and KSHV replication, we xeno29

grafted telomerase-immortalized human umbilical vein endothelial cells that are infected with KSHV (TIVE-KSHV) into hyperglycemic and normal nude mice. The injected cells expressed significantly higher levels of KSHV lytic genes in hyperglycemic mice than in normal mice. We further demonstrated that high …

Persistent Low-Level Replication Of Sivδnef Drives Maturation Of Antibody And Cd8 T Cell Responses To Induce Protective Immunity Against Vaginal Siv Infection, Sama Adnan, R. Keith Reeves, Jacqueline Gillis, Fay E. Wong, Yi Yu, Jeremy V. Camp, Qingsheng Li, Michelle Connole, Yuan Li, Michael Piatak Jr., Jeffrey D. Lifson, Wenjun Li, Brandon F. Keele, Pamela A. Kozlowski, Ronald C. Desrosiers, Ashley T. Haase, R. Paul Johnson

Nebraska Center for Virology: Faculty Publications

Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef …

Antibiotic Efficacy And Interaction In Escherichia Coli During Varying Nutrient Conditions, Kristina K. Millar

Scripps Senior Theses

Due to the recent rise in antibiotic resistant pathogens, and the difficulties surrounding the quest for new antibiotics, many researchers have started revisiting antibiotic interactions in hopes of finding new treatment options. The primary outcome of this project was to examine the efficacy of concomitant antibiotic use under varying nutrient conditions, to identify variations in antibiotic interactions. Antibiotic interactions were studied, utilizing E. coli as a model bacterial system, grown in four different media types. E. coli cultures were treated with streptomycin, tobramycin, erythromycin, and amikacin individually and in a pairwise fashion at varying doses. We found that at least …

Frequency And Etiology Of Community-Acquired Bloodstream Infection In Hospitalized Febrile Children, Tufail Soomro, Shiyam Sunder Tikmani, Sumera Aziz Ali

Community Health Sciences

Background: Blood stream infection is a serious problem that needs immediate attention and treatment. We aim to identify the frequency of common organisms in blood culture of febrile pediatric patients so that empirical antibiotic therapy can be started timely.
Methods: This cross-sectional study was conducted in pediatric ward Civil Hospital Sukkur from 1st May 2013 to 31st October 2014. Children of both genders who are between the age of one month to 15 years admitted to the pediatric ward with a fever of > 38.0 c and with a history of fever ˃ two days and whose blood culture has been …

Determining The Role Of Poly [Adp-Ribose] Polymerase 1 (Parp-1) In Retroviral Infection, Luis Valdes Rodriguez

Open Access Theses & Dissertations

Possible links between PARP-1 and HIV-1 have been previously reported but the role of this protein during viral infection has remained elusive. Based on the high evolutionary conservation of PARP-1, from Drosophila to humans, we have been able to counteract the difficulties related with the functional redundancy manifested in the PARP family by studying the influence of PARP-1 on the expression of an endogenous retrovirus using the chicken B lymphoblastoid cell line DT40, this cell line exhibits low PARP-1 functional redundancy and is viable after PARP-1 knockout. We have determined that the transcription level of the endogenous retrovirus RAV-1 is …

Central, Extraventricular And Atypical Neurocytomas: A Clinicopathologic Study Of 35 Cases From Pakistan Plus A Detailed Review Of The Published Literature, Zubair Ahmad, Nasir Ud Din, Aisha Memon, Mohammad Usman Tariq, Romana Idrees, Sheema Hasan

Department of Pathology and Laboratory Medicine

Background: Central neurocytomas are rare neuronal neoplasms with a favorable prognosis. They are typically located in the lateral ventricles of the brain and mostly histologically correspond to WHO grade II with a Mib 1 labelling index of 2 % and are designated as "atypical neurocytomas.AIM: The aim of our study was to describe the common as well as unusual morphologic features and the role of various immunohistochemical stains in the diagnosis of these rare tumors.MATERIALS AND Methods: We retrieved and reviewed 35 cases diagnosed between 2001 and 2015.Results: Sixty percent of patients were males, and the mean age was 26 …

Errors In Surgical Pathology Reports: A Study From A Major Center In Pakistan, Zubair Ahmad, Romana Idrees, Nasir Uddin, Arsalan Ahmed, Saira Fatima

Department of Pathology and Laboratory Medicine

Background:
Errors in surgical pathology diagnosis can have serious consequences for the patient. Since the final product of a surgical pathology lab is the report, errors can be picked by reviewing reports of cases.AIM: To determine the frequency and types of error in surgical pathology reports of cases signed out in 2014 in a laboratory in Karachi, Pakistan.
Material and Methods:
All surgical pathology reports in which changes were made in the original report after sign out and an amended report was issued were included. Errors included: (1) misinterpretations; (2) missing critical information; (3) erroneous critical information; (4) misidentification; and …

Flaviviruses As A Cause Of Undifferentiated Fever In Sindh Province, Pakistan: A Preliminary Report, Erum Khan, Joveria Q. Farooqi, Kelli L. Barr, Dhani Prakoso, Amna Nasir, Akbar Kanji, Sadia Shakoor, Faisal Riaz Malik, Rumina Hasan, John A. Lednicky

Department of Pathology and Laboratory Medicine

Arboviral diseases are expanding worldwide, yet global surveillance is often limited due to diplomatic and cultural barriers between nations. With human encroachment into new habitats, mosquito-borne viruses are also invading new areas. The actual prevalence of expanding arboviruses is unknown in Pakistan due to inappropriate diagnosis and poor testing for arboviral diseases. The primary objective of this study was to document evidence of flavivirus infections as the cause of undifferentiated fever in Pakistan. Through a cooperative effort between the USA and Pakistan, patient exposure to dengue virus (DENV), West Nile virus (WNV), and Japanese encephalitis virus (JEV) was examined in …

Sporadic Early Onset Colorectal Cancer In Pakistan: A Case- Control Analysis Of Microsatellite Instability, Sabeehuddin Siddique, Kanwal Tariq, Sobia Rafiq, Ahmed Raheem, Rashida Ahmed, Munira Shabbir-Moosajee, Kulsoom Ghias

Department of Pathology and Laboratory Medicine

Background: Early onset sporadic colorectal cancer (CRC) is a biologically and clinically distinct entity hypothesized to exhibit differences in histological features and microsatellite instability (MSI) as compared to typical onset CRC. This study compared the MSI status, mismatch repair enzyme deficiency and clinicopathological features of early onset (aged ≤45 years) with controls (>45 years).
Materials and Methods: A total of 30 cases and 30 controls were analyzed for MSI status using the Bethesda marker panel. Using antibodies against hMLH1, hMSH2 and hMSH6, mismatch repair protein expression was assessed by immunohistochemistry. Molecular characteristics were correlated with clinicopathological features.
Results: …

Sequence-Based Methods For Detecting And Evaluating The Human Gut Mycobiome, Mallory J. Suhr, Nabaraj Banjara, Heather E. Hallen-Adams

Department of Food Science and Technology: Faculty Publications

We surveyed the fungal microbiota in 16 fecal samples from healthy humans with a vegetarian diet. Fungi were identified using molecular cloning, 454 pyrosequencing and a Luminex analyte specific reagent (ASR) assay, all targeting the ITS region of the rRNA genes. Fungi were detected in each fecal sample and at least 46 distinct fungal operational taxonomic units (OTUs) were detected, from two phyla — Ascomycota and Basidiomycota. Fusarium was the most abundant genus, followed by Malassezia, Penicillium, Aspergillus, and Candida. Commonly detected fungi such as Aspergillus and Penicillium, as well as known dietary fungi Agaricus bisporus and …

Complete Genome Sequence Of Highly Virulent Porcine Reproductive And Respiratory Syndrome Virus Variants That Recently Emerged In The United States, Aspen M. Workman, Timothy P.L. Smith, Fernando A. Osorio, Hiep L.X. Vu

Nebraska Center for Virology: Faculty Publications

A recent outbreak of particularly virulent disease caused by porcine reproductive and respiratory syndrome virus has occurred in swine herds across the United States. We report here the complete genome sequence of eight viral isolates from four Nebraska herds experiencing an outbreak of severe disease in 2016.