Browsing by Author "McNulty, Steven"

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    Mycobacterial Interspersed Repetitive-Unit-Variable-Number Tandem-Repeat (MIRU-VNTR) Genotyping of Mycobacterium intracellulare for Strain Comparison with Establishment of a PCR-Based Database
    Iakhiaeva, Elena; McNulty, Steven; Brown-Elliott, Barbara A.; Falkinham, Joseph O. III; Williams, Myra D.; Vasireddy, Ravikiran; Wilson, Rebecca W.; Turenne, Christine; Wallace, Richard J. Jr. (American Society for Microbiology, 2012-11-21)
    Strain comparison is important to population genetics and to evaluate relapses in patients with Mycobacterium avium complex (MAC) lung disease, but the "gold standard" of pulsed-field gel electrophoresis (PFGE) is time-consuming and complex. We used variable-number tandem repeats (VNTR) for fingerprinting of respiratory isolates of M. intracellulare from patients with underlying bronchiectasis, to establish a nonsequence-based database for population analysis. Different genotypes identified by PFGE underwent species identification using a 16S rRNA gene multiplex PCR. Genotypes of M. intracellulare were confirmed by internal transcribed spacer 1 (ITS1) sequencing and characterized using seven VNTR primers. The pattern of VNTR amplicon sizes and repeat number defined each specific VNTR type. Forty-two VNTR types were identified among 84 genotypes. PFGE revealed most isolates with the same VNTR type to be clonal or exhibit similar grouping of bands. Repetitive sequence-based PCR (rep-PCR) showed minimal pattern diversity between VNTR types compared to PFGE. Fingerprinting of relapse isolates from 31 treated patients using VNTR combined with 16S multiplex PCR unambiguously and reliably distinguished different genotypes from the same patient, with results comparable to those of PFGE. VNTR for strain comparison is easier and faster than PFGE, is as accurate as PFGE, and does not require sequencing. Starting with a collection of 167 M. intracellulare isolates, VNTR distinguished M. intracellulare into 42 clonal groups. Comparison of isolates from different geographic areas, habitats, and clinical settings is now possible.
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    Nontuberculous Mycobacteria in Household Plumbing as Possible Cause of Chronic Rhinosinusitis
    Tichenor, Wellington S.; Thurlow, Jennifer; McNulty, Steven; Brown-Elliott, Barbara A.; Wallace, Richard J. Jr.; Falkinham, Joseph O. III (2012-10)
    Symptoms of chronic rhinosinusitis (CRS) often persist despite treatment. Because nontuberculous nnycobacteria (NTM) are resistant to commonly used antimicrobial drugs and are found in drinking water that patients may use for sinus irrigation, we investigated whether some CRS patients were infected with NTM in New York, New York, USA, during 2001-2011. Two approaches were chosen: 1) records of NTM-infected CRS patients were reviewed to identify common features of infection and Mycobacterium species; 2) samples from plumbing in households of 8 NTM-infected patients were cultured for NTM presence. In 3 households sampled, M. avium sharing rep-PCR and pulsed field gel electrophoresis fingerprints identified M. avium isolates clonally related to the patients' isolates. We conclude that patients with treatment-resistant CRS may be infected with NTM and should have cultures performed for NTM so appropriate therapy can be instituted. In addition, the results suggest that CRS patients can be infected by NTM in their household plumbing.
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    Soybean producers guide
    Vann, Rachel; Everman, Wesley; Holshouser, David L.; Huseth, Anders; Reisig, Dominic; Thiessen, Lindsey (U.S. Department of Agriculture Forest Service, Southern Research Station, 2021-11-01)
    This is 1 of 23 guides to help Southeastern U.S. producers of economically important agricultural commodities build resilience to, prepare for, and recover from hurricane impacts. All guides can be found on the USDA Southeast Climate Hub.