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71.
Ronald N. Jones Kenneth E. Aldridge Arthur L. Barry Peter C. Fuchs E. Hugh Gerlach Michael A. Pfaller John A. Washington II 《Diagnostic microbiology and infectious disease》1988,10(4):221-240
Lomefloxacin (NY-198 or SC-47111) is a difluoro-quinolone derivative having a C-methyl at the 3-position of the piperazine ring, thus minimizing its metabolic alteration in vivo. In our research, its antimicrobial activity was most similar to that of difloxacin, enoxacin, fleroxacin, and norfloxacin but usually less than that of ciprofloxacin and ofloxacin against most species. Lomefloxacin shared cross-resistance with other 4-quinolones but remained very active against ceftazidime-resistant organisms, including stably derepressed beta-lactamase producing Gram-negative bacilli. Lower pH increased the lomefloxacin MICs. MBCs were usually identical to the measured MIC, and the lomefloxacin MICs were not significantly increased by high inoculum concentrations. The
were found to have a very low rate of spontaneous mutation to lomefloxacin resistance (10−8–10−9). In vitro tests by 5-μg and 10-μg lomefloxacin disks and dilution methods were correlated, and the 10-μg disk was recommended for clinical trials using a ≤4 μg/ml susceptible breakpoint. The quality assurance guidelines for dilution tests were determined by a multilaboratory study. 相似文献
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Histamine reduces boron neutron capture therapy‐induced mucositis in an oral precancer model 下载免费PDF全文
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Emmi Helle Aldo Córdova-Palomera Tiina Ojala Priyanka Saha Praneetha Potiny Stefan Gustafsson Erik Ingelsson Michael Bamshad Deborah Nickerson Jessica X. Chong University of Washington Center for Mendelian Genomics Euan Ashley James R. Priest 《Genetic epidemiology》2019,43(2):215-226
Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes. 相似文献
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Naoya Uchida Kareem N Washington Coen J Lap Matthew M Hsieh John F Tisdale 《Molecular therapy》2011,19(1):133-139
Position effects limit the curative potential of gene transfer strategies for the hemoglobinopathies by inducing clonal variability of transgene expression. We evaluated the mitigating effects of the chicken hypersensitivity site 4 (HS4) insulator among lentiviral vector-transduced human hematopoietic cells. We constructed various lentiviral vectors using a green fluorescent protein (GFP) reporter under the control of a reverse-oriented murine stem cell virus (MSCV)-long-term repeat (LTR) promoter or a reverse-oriented β-globin expression cassette. A full-length HS4, a tandem HS4 core, and a single core insulator were inserted into the 3′ LTR in both forward and reverse orientation. All but the reverse single core insulator significantly decreased titers. All reduced %GFP without increasing mean fluorescence intensity (MFI) among erythroid progeny of transduced human CD34+ cells. A lower coefficient of variation (CV) was observed only among progeny of the full-length vector-transduced cells, yet a fivefold reduction in transduction efficiency was observed. In xenografted mice, the single core insulator decreased both the %GFP and the MFI at 4 and 8 weeks after transplantation with no difference in CVs. These data demonstrate that the inclusion of HS4 insulator elements lowers viral titers, reduces efficiency of transduction, and produces minimal effects on transgene expression among human hematopoietic cells in vitro and in vivo. 相似文献
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Comparison of isolation of Haemophilus vaginalis (Corynebacterium vaginale) from peptone-starch-dextrose agar and Columbia colistin-nalidoxic acid agar. 下载免费PDF全文
A total of 447 cervical or vaginal specimens were inoculated in parallel onto peptone-starch-dextrose (PSD) and Columbia colistin (10 mg/ml)-nalidixic acid (15 mug/ml) (CNA) agar and were incubated for 48 h at 35 degrees C in an atmosphere with 2 to 10% CO2. One hundred (22.4%) of the cultures were positive for Haemophilus vaginalis. Forty-eight of the isolates were recovered from both PSD and Columbia CNA agar, five from PSD only, and 47 from Columbia CNA agar only (P less than 0.001). On Columbia CNA agar, 76 of the isolates were detected after 24 h of incubation, and the remainder were detected within 4 days of incubation. 相似文献
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