Steven H Hinrichs

University of Nebraska Medical Center, Omaha, Nebraska, United States

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Publications (198)1156.78 Total impact

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    ABSTRACT: The taxonomic status of the bacterium Wolbachia persica is described and based on the evidence presented, the transfer of this species to the genus Francisella and the renaming to Francisella persica comb. nov. is proposed. This reclassification is supported by data generated from genomic comparisons of the W. persica type strain ATCC VR-331T (FSC845T, DSM 101678T) to other near neighbors, including F. tularensis subspecies novicida. The full-length ATCC VR-331T 16S rRNA gene had 98.5% nucleotide identity to the cognate gene in F. tularensis, with the highest similarity to subspecies novicida. Phylogenetic trees of full-length 16S rRNA, gyrA, and recA from Alphaproteobacteria Wolbachia and Gammaproteobacteria Francisella species indicated that W. persica type strain ATCC VR-331T was most closely related to members of the genus Francisella and not Wolbachia. Local collinear blocks within the chromosome of ATCC VR-331T had considerable homology with F. tularensis subspecies novicida, but not with any Wolbachia strain. The genomes of ATCC VR-331T and F. tularensis subspecies novicida type strain U112T (ATCC 15482T) contained an average nucleotide identity mean of 88.72% and median of 89.18%. Importantly, the ATCC VR-331T genome contained one Francisella Pathogenicity Island, similar to F. tularensis subspecies novicida, as well as Francisella-specific gene fopA1 and F. tularensis-specific genes fopA2 and lpnA (also referred to as tul4). In contrast to the obligate intracellular Wolbachia genus, ATCC VR-331T and facultative intracellular Francisella can replicate in specialized cell-free media. Collectively, these results demonstrate that the type strain for Francisella persica comb. nov. is ATCC VR-331T (FSC845T, DSM 101678T).
    No preview · Article · Jan 2016 · International Journal of Systematic and Evolutionary Microbiology
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    ABSTRACT: Introduction: Menaquinone is used for transporting electrons and is essential for the aerobic and anaerobic respiratory systems of all pathogens and prokaryotes. Many Gram-positive bacteria use only menaquinone in the electron transport system. Thus, menaquinone biosynthesis is a potential target for the development of inhibitors against bacteria including drug-resistant pathogens. Results: After modeling, synthesis and in vitro testing, we determined that 7-methoxy-2-naphthol-based inhibitors targeted the MenA enzyme of the menaquinone biosynthesis pathway. The developmental compounds 1 and 2 were active against Mycobacterium tuberculosis and methicillin-resistant Staphylococcus aureus with a minimal inhibitory concentration of 3-5 μg/ml. Conclusion: Nontraditional bicyclic inhibitors, compounds 1 and 2 could serve as lead compounds for the development of an antimicrobial agent, with activities against M. tuberculosis and methicillin-resistant S. aureus.
    No preview · Article · Jan 2016 · Future medicinal chemistry
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    ABSTRACT: Rapid, reliable and easy to use diagnostic assays for detection of Zaire ebolavirus (ZEBOV) are urgently needed. The goal of this study was to examine the percentage agreement among Emergency Use Authorization (EUA) tests for the detection of ZEBOV nucleic acid including the BioFire FilmArray® BioThreat (BT) panel, the FilmArray BT E-panel and the NP2 and VP40 quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) assays from the Centers for Disease Control and Prevention (CDC). Specimens used in this study included whole blood spiked with inactivated ZEBOV at known titers and whole blood, plasma and urine clinical specimens from persons diagnosed with Ebola virus disease (EVD). The percentage agreement for FilmArray and qRT-PCR assays using contrived whole blood specimens was 100% (6/6) for each ZEBOV dilution from 4x10(7)-4x10(2) virus/ml as well as the no-virus negative control. The limit of detection for FilmArray and qRT-PCR based on duplicate positive results was determined to be 4x10(2) inactivated ZEBOV/ml. Percentage agreement between FilmArray and qRT-PCR using clinical specimens from patients with EVD was 85% (23/27) when testing whole blood, 90%(18/20) when testing whole blood by FilmArray and matched plasma by qRT-PCR and 85% (11/13) when testing urine. Of 60 specimens, eight discordant results were noted with ZEBOV nucleic acid detected only by FilmArray in four specimens and only by qRT-PCR in the remaining four. These findings demonstrate that the rapid and easy to use FilmArray panels are effective tests for evaluating patients with EVD. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
    Full-text · Article · Jul 2015 · Journal of clinical microbiology
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    ABSTRACT: Although Francisella tularensis is considered a monomorphic intracellular pathogen, molecular genotyping and virulence studies have demonstrated important differences within the tularensis subspecies (type A). To evaluate genetic variation within type A strains, sequencing and assembly of a new subtype A.II genome was achieved for comparison to other completed F. tularensis type A genomes. In contrast with the F. tularensis A.I strains (SCHU S4, FSC198, NE061598, and TI0902), substantial genomic variation was observed between the newly sequenced F. tularensis A.II strain (WY-00W4114) and the only other publically available A.II strain (WY96-3418). Genome differences between WY-00W4114 and WY96- 3418 included three major chromosomal translocations, 1580 indels, and 286 nucleotide substitutions of which 159 were observed in predicted open reading frames and 127 were located in intergenic regions. The majority of WY-00W4114 nucleotide deletions occurred in intergenic regions, whereas most of the insertions and substitutions occurred in predicted genes. Of the nucleotide substitutions, 48 (30%) were synonymous and 111 (70%) were nonsynonymous. WY-00W4114 and WY96-3418 nucleotide polymorphisms were predominantly G/C to A/T allelic mutations, with WY-00W4114 having more A+T enrichment. In addition, the A.II genomes contained a considerably higher number of intact genes and longer repetitive sequences, including transposon remnants than the A.I genomes. Together these findings support the premise that F. tularensis A.II may have a fitness advantage compared to the A.I subtype due to the higher abundance of functional genes and repeated chromosomal sequences. A better understanding of the selective forces driving F. tularensis genetic diversity and plasticity is needed.
    Full-text · Article · Apr 2015
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    ABSTRACT: The objective of this research was to determine test intervals between intraoperator case reviews to minimize the impact of recall. Three pathologists were presented with a group of 120 slides and subsequently challenged with a study set of 120 slides after 2-week and 4-week intervals. The challenge set consisted of 60 slides seen during the initial review and 60 slides previously unseen within the study. Pathologists rendered a diagnosis for each slide and indicated whether they recalled seeing the slide previously (yes/no). Two weeks after having been shown 60 cases from a challenge set of 120 cases, the pathologists correctly remembered 26, 22, and 24 cases or 40% overall. After 4 weeks, the pathologists correctly recalled 31% of cases previously seen. Pathologists were capable of recalling from memory cases seen previously at 2 and 4 weeks. Recall rates may be sufficiently high to affect intraobserver study design. Copyright© by the American Society for Clinical Pathology.
    No preview · Article · Mar 2015 · American Journal of Clinical Pathology

  • No preview · Article · Jan 2015 · American Journal of Clinical Pathology
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    Marilynn A Larson · Paul D Fey · Steven H Hinrichs · Peter C Iwen
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    ABSTRACT: Tularemia in the United States was examined by reviewing 106 Francisella tularensis isolates, mostly from Nebraska, collected during 1998-2012: 48% of Nebraska cases were cat-associated; 7/8 human cases were caused by subtype A.I. A vaccine is needed to reduce feline-associated tularemia, and cat owners should protect against bites/scratches and limit their pet's outdoor access.
    Full-text · Article · Dec 2014 · Emerging infectious diseases
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    Full-text · Article · Oct 2014 · Laboratory Medicine
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    ABSTRACT: This study investigated the diagnostic accuracy of whole slide imaging (WSI) in breast needle biopsy diagnosis in comparison with standard light microscopy (LM). The study examined the effects of image capture magnification and computer monitor quality on diagnostic concordance of WSI and LM. Four pathologists rendered diagnoses using WSI to examine 85 breast biopsies (92 parts; 786 slides) consisting of benign and malignant cases. Each WSI case was evaluated using images captured at either 20x or 40x magnifications and viewed using a DICOM grade, color-calibrated monitor or a standard, desktop LCD monitor. For each combination, the WSI result was compared to the original, LM diagnosis. The overall concordance rate observed between WSI and LM was 97.1% (95% CI:94.3%-98.5%). After a washout period, all cases were reviewed a second time by each pathologist after using LM, and the second LM diagnosis was compared to the WSI diagnosis rendered by the same pathologist. Intraobserver concordance between WSI and LM was 95.4% (95% CI:92.2%- 97.4%). The second LM diagnoses were also compared to the original LM diagnoses, and the observed interobserver LM concordance rate was 97.3% (95% CI:93.1% -99.0%). The study data demonstrated that breast needle biopsy diagnoses rendered by WSI were equivalent to diagnoses rendered by LM. No diagnostic differences were detected between the underlying viewing system parameters of monitor quality and image capture resolution. The results of this study demonstrated that WSI can be effectively utilized in subspecialty diagnostic cases where a minimum amount of tissue is available.
    No preview · Article · Aug 2014 · Human pathology
  • Marilynn A Larson · Oksana Lockridge · Steven H Hinrichs
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    ABSTRACT: Human butyrylcholinesterase (BChE) protects against the toxicity of organophosphorus nerve agents and pesticides. BChE purified from human plasma is limited and pathogen carry-over is a concern. Unlike the native BChE tetrameric complex with a residence time of days, recombinant BChE (rBChE) is produced predominantly as dimers and monomers that are cleared from the circulation within minutes. Assembly into tetramers requires incorporation of proline-rich peptides, a process that was thought to occur intracellularly. Our goal was to determine whether polyproline added to rBChE under cell-free conditions would promote tetramerization. Secreted rBChE was purified by procainamide affinity chromatography, and synthetic polyprolines (8-mer to 300-mer) were tested to determine their effect on tetramer assembly. These studies demonstrated that 90-98% of purified rBChE (65 µM) could be assembled into tetramers when incubated with synthetic 17-mer or 50-mer polyproline peptides (100 µM) for 1.5 h at 25˚C. However, rBChE tetramerization was inefficient with smaller 8-mer polyproline peptides and larger 300-mer polyproline proteins. Collectively, these studies demonstrated that the eukaryotic cellular machinery is not required for assembly of active BChE into tetramers and that this process can occur in vitro with purified rBChE in the presence of peptides containing 15 to 50 consecutive proline residues.
    No preview · Article · Jun 2014 · Biochemical Journal
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    ABSTRACT: This research investigated the use of SNOMED CT to represent diagnostic tissue morphologies and notable tissue architectures typically found within a pathologist's microscopic examination report to identify gaps in expressivity of SNOMED CT for use in anatomic pathology. 24 breast biopsy cases were reviewed by two board certified surgical pathologists who independently described the diagnostically important tissue architectures and diagnostic morphologies observed by microscopic examination. In addition, diagnostic comments and details were extracted from the original diagnostic pathology report. 95 unique clinical statements were extracted from 13 malignant and 11 benign breast needle biopsy cases. 75% of the inventoried diagnostic terms and statements could be represented by valid SNOMED CT expressions. The expressions included one pre-coordinated expression and 73 post-coordinated expressions. No valid SNOMED CT expressions could be identified or developed to unambiguously assert the meaning of 21 statements (ie, 25% of inventoried clinical statements). Evaluation of the findings indicated that SNOMED CT lacked sufficient definitional expressions or the SNOMED CT concept model prohibited use of certain defined concepts needed to describe the numerous, diagnostically important tissue architectures and morphologic changes found within a surgical pathology microscopic examination. Because information gathered during microscopic histopathology examination provides the basis of pathology diagnoses, additional concept definitions for tissue morphometries and modifications to the SNOMED CT concept model are needed and suggested to represent detailed histopathologic findings in computable fashion for purposes of patient information exchange and research. UNMC Institutional Review Board ID# 342-11-EP.
    Preview · Article · May 2014 · Journal of the American Medical Informatics Association
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    Full-text · Article · Jan 2014
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    ABSTRACT: Acute respiratory infections are a significant concern throughout the world, contributing to 4.25 million deaths annually. One such pathogen, H5N1 avian influenza, has the potential to become the next pandemic threat. While currently not transmitted human-to-human, recent cases of H5N1 have been shown to result in a 60% fatality rate and an increasing resistance to antiviral treatments. However, because of the rapid mutation rate of RNA viruses like influenza, it is likely that human-to-human transmission is imminent, motivating the need for efficacious vaccines against pandemic influenzas. Polyanhydride nanovaccines have been shown to be a versatile platform for the delivery of subunit vaccines. Nanoparticles composed of sebacic acid (SA), 1,6-bis-(p-carboxyphenoxy) hexane (CPH), and 1,8-bis-(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG), and their copolymers have been shown to sustain the release of encapsulated proteins while enhancing internalization by antigen presenting cells. Polyanhydride nanovaccines have also been shown to have immunomodulatory capabilities inducing both high avidity antibody titers as well as cell-mediated immune responses. Previously, we have demonstrated that polyanhydride nanoparticles are capable of stably releasing recombinant H5 hemagglutinin, an antigen for H5N1 influenza. In this work, we characterized the in vivo immune responses generated by polyanhydride-based subunit nanovaccines. Polyanhydride nanovaccine formulations encapsulating rH5 were found to elicit high antigen-specific antibody titers as well as virus-neutralizing antibody titers. Likewise, enhanced T cell memory responses were observed at 63 days post immunization. Finally, the efficacy of a nanovaccine formulation was evaluated using a live viral challenge. All these studies together indicate that polyanhydride nanovaccines offer a patient-friendly and efficacious platform for next generation influenza A vaccines.
    No preview · Conference Paper · Nov 2013
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    ABSTRACT: Patient: 75-year-old Caucasian male. Chief Complaint: Frequent diarrhea. History of Present Illness: The patient had a history of Crohn's disease, initially diagnosed in 1976 with a positive test for toxigenic Clostridium difficile (C. difficile) in August 2011, successfully treated with methronidazole (500 mg PO bid ×10 d). There was a concern that diarrhea may be a result of C. difficile recurrence. Past Medical History: The patient had an extensive medical history, including eosinophilia (8%, normal 0%-7%) in October 2011, gastroesophageal reflux disease, anemia secondary to Crohn's disease, coronary artery disease, hypertension, osteoarthritis, and Type II diabetes mellitus. Additionally, the patient has severe Crohn's disease which involves the terminal ileum and colon, and has undergone multiple small bowel resections as well as a colectomy. Medications included immunomodulatory therapy with balsalazide (Colazal), azathioprine (Imuran), infliximab (Remicade), ranitidine, and prednisone for both Crohn's disease and osteoarthritis. Previous biopsies of the small intestine and colon (before the current presentation) indicated changes consistent with Crohn's disease. Travel History: The patient was originally from Louisiana, and briefly lived in Las Vegas, NV. For approximately 40 years, he has lived in western Iowa. The patient did not have a history of foreign travel nor had he recently traveled outside of Iowa or Nebraska. He drives a bus for a local business. Principle Laboratory Findings: Loose brown stool was collected in December 2011 and submitted for laboratory testing for toxigenic C. difficile and cultured for enteric pathogens. An ova and parasites exam was not ordered at that time. Salmonella, Shigella, and Campylobacter species, as well as Shiga toxin producing-Escherichia coli, were not detected; the toxigenic C. difficile assay was negative. A laboratory technologist noted the presence of small trails of displaced bacteria on the blood agar plate from the original stool culture (Image 1). From this, a full ova and parasites exam was performed on the stool specimen.
    Preview · Article · Oct 2013 · Laboratory Medicine
  • Steven H Hinrichs · Patina Zarcone

    No preview · Article · Sep 2013 · Public Health Reports
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    ABSTRACT: Purpose: A comprehensive strategy was developed and validated for the identification of pathogens from closely related near neighbors using both chromosomal and protein biomarkers, with emphasis on distinguishing Yersinia pestis from the ancestral bacterium Yersinia pseudotuberculosis. Experimental design: Computational analysis was used to discover chromosomal targets unique to Y. pestis. Locus identifier YPO1670 was selected for further validation and PCR was used to confirm that this biomarker was exclusively present in Y. pestis strains, while absent in other Yersinia species. RT-PCR and Western blot analyses were utilized to evaluate YPO1670 expression and MRM MS was performed to identify the YPO1670 protein within cell lysates. Results: The described study validated that YPO1670 was exclusive to Y. pestis. PCR confirmed the locus to be unique to Y. pestis. The associated transcript and protein were produced throughout growth with the highest abundance occurring in stationary phase and MRM MS conclusively identified the YPO1670 protein in cell extracts. Conclusions and clinical relevance: These findings validated YPO1670 as a reliable candidate biomarker for Y. pestis and that a dual DNA and protein targeting approach is feasible for the development of next-generation assays to accurately differentiate pathogens from near neighbors.
    No preview · Article · Jun 2013 · PROTEOMICS - CLINICAL APPLICATIONS
  • Walter S Campbell · Kirk W Foster · Steven H Hinrichs
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    ABSTRACT: The ability to transfer image markup and annotation data from one scanned image of a slide to a newly acquired image of the same slide within a single vendor platform was investigated. The goal was to study the ability to use image markup and annotation data files as a mechanism to capture and retain pathologist knowledge without retaining the entire whole slide image (WSI) file. Accepted mathematical principles were investigated as a method to overcome variations in scans of the same glass slide and to accurately associate image markup and annotation data across different WSI of the same glass slide. Trilateration was used to link fixed points within the image and slide to the placement of markups and annotations of the image in a metadata file. Variation in markup and annotation placement between WSI of the same glass slide was reduced from over 80 μ to less than 4 μ in the x-axis and from 17 μ to 6 μ in the y-axis (P < 0.025). This methodology allows for the creation of a highly reproducible image library of histopathology images and interpretations for educational and research use.
    No preview · Article · Feb 2013
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    ABSTRACT: We describe the transfer of blaKPC-4 from Enterobacter cloacae to Serratia marcescens in a single patient. DNA sequencing revealed that KPC-4 was encoded on an IncL/M plasmid, pNE1280, closely related to pCTX-M360. Further analysis found that KPC-4 was encoded within a novel Tn4401 element (Tn4401f) containing a truncated tnpA and lacking tnpR, ISKpn7 left, and Tn4401 IRL-1, which are conserved in other Tn4401 transposons. This study highlights the continued evolution of Tn4401 transposons and movement to multiple plasmid backbones that results in acquisition by multiple species of Gram-negative bacilli.
    Full-text · Article · Oct 2012 · Antimicrobial Agents and Chemotherapy
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    Scott A Koepsell · Steven H Hinrichs · Peter C Iwen
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    ABSTRACT: A real-time PCR assay to detect Histoplasma capsulatum in formalin-fixed, paraffin-embedded (FFPE) tissue is described. The assay had an analytical sensitivity of 6 pg/μl of fungal DNA, analytical specificity of 100%, and clinical sensitivity of 88.9%. This proof-of-concept study may aid in the diagnosis of histoplasmosis from FFPE tissue.
    Full-text · Article · Aug 2012 · Journal of clinical microbiology
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    ABSTRACT: The aim of this study was to demonstrate a prototype tool for measuring infectivity of an aerosolized human pathogen - influenza A/PR/8/34 (H1N1) virus - using a small-animal model in the Controlled Aerosol Test System (CATS). Intranasal inoculation of nonadapted H1N1 virus into C57BL, BALB/c and CD-1 mice caused infection in all three species. Respiratory exposure of CD-1 mice to the aerosolized virus at graduated doses was accomplished in a modified rodent exposure apparatus. Weight change was recorded for 7 days postexposure, and viral populations in lung tissue homogenates were measured post mortem by DNA amplification (qRT-PCR), direct fluorescence and microscopic evaluation of cytopathic effect. Plots of weight change and of PCR cycle threshold vs delivered dose were linear to threshold doses of ~40 TCID(50) and ~12 TCID(50) , respectively. MID(50) for inspired H1N1 aerosols in CD-1 mice is between 12 and 40 TCID(50) ; proportionality to dose of weight loss and viral populations makes the CD-1 mouse a useful model for measuring infectivity by inhalation. In the CATS, this mouse-virus model provides the first quantitative method to evaluate the ability of respiratory protective technologies to attenuate the infectivity of an inspired pathogenic aerosol.
    No preview · Article · Jul 2012 · Journal of Applied Microbiology

Publication Stats

7k Citations
1,156.78 Total Impact Points

Institutions

  • 1994-2016
    • University of Nebraska Medical Center
      • • Department of Pathology and Microbiology
      • • Department of Biochemistry
      Omaha, Nebraska, United States
  • 2010-2014
    • The Nebraska Medical Center
      Omaha, Nebraska, United States
  • 1992-2011
    • University of Nebraska at Omaha
      • Department of Pathology and Microbiology
      Omaha, Nebraska, United States
  • 2007-2010
    • University of Nebraska at Lincoln
      • Department of Food Science and Technology
      Lincoln, Nebraska, United States
  • 2009
    • University of Nottingham
      • School of Chemistry
      Nottingham, ENG, United Kingdom
  • 2002
    • Centers for Disease Control and Prevention
      Атланта, Michigan, United States
  • 1999
    • University of Virginia
      Charlottesville, Virginia, United States
  • 1996
    • St. Luke's University Hospital - Bethlehem
      Bethlehem, Pennsylvania, United States
  • 1985-1996
    • University of California, Davis
      • • Department of Nutrition
      • • School of Medicine
      Davis, California, United States
  • 1989
    • National Cancer Institute (USA)
      • Laboratory of Molecular Biology
      Maryland, United States