Search

In this study, an embryogenic callus induction and proliferation system for Hippeastrum vittatum was established, with the tender bulbs as expiants. And then the sensitivity of the expiants and calli to kanamycin and hygromycin was evaluated. The results suggested that the embryogenic calli were induced from tender bulbs and cultured in Murashige and Skoog (MS) medium supplemented with 0.5 mg/L N-phenyl-N'-l, 2,3-thiadiazol-5-ylurea (TDZ), 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D), and 30 g/L sucrose (pH5.8) in the dark at 25 ± 1°C. Further study of the influence of kanamycin and hygromycin on callus induction and multiplication showed that, the lethal doses of kanamycin and hygromycin to bulb expiants were 100 and 30 mg/L, respectively. All expiants of H. vittatum died on the medium supplemented with 100 mg/L kanamycin or 30 mg/L hygromycin at the induction stage, and callus proliferation was completely inhibited by 100 mg/L kanamycin or 25 mg/L hygromycin, and all the calli died at last. These results will provide important reference for further studies of transgenic H. vittatum. [ABSTRACT FROM AUTHOR]

Background: The emergence and spread of Carbapenem-resistant Escherichia coli (CREC) is becoming a serious problem in Chinese hospitals, however, the data on this is scarce. Therefore, we investigate the risk factors for healthcare-associated CREC infection and study the incidence, antibiotic resistance and medical costs of CREC infections in our hospital.Methods: We conducted a retrospective, matched case-control-control, parallel study in a tertiary teaching hospital. Patients admitted between January 2012 and December 2015 were included in this study. For patients with healthcare-associated CREC infection, two matched subject groups were created; one group with healthcare-associated CSEC infection and the other group without infection.Results: Multivariate conditional logistic regression analysis demonstrated that prior hospital stay (<6 months) (OR:3.96; 95%CI:1.26-12.42), tracheostomy (OR:2.24; 95%CI: 1.14-4.38), central venous catheter insertion (OR: 8.15; 95%CI: 2.31-28.72), carbapenem exposure (OR: 12.02; 95%CI: 1.52-95.4), urinary system disease (OR: 16.69; 95%CI: 3.01-89.76), low hemoglobin (OR: 2.83; 95%CI: 1.46-5.50), and high blood glucose are associated (OR: 7.01; 95%CI: 1.89-26.02) with CREC infection. Total costs (p = 0.00), medical examination costs (p = 0.00), medical test costs (p = 0.00), total drug costs (p = 0.00) and ant-infective drug costs (p = 0.00) for the CREC group were significantly higher than those for the no infection group. Medical examination costs (p = 0.03), total drug costs (p = 0.03), and anti-infective drug costs (p = 0.01) for the CREC group were significantly higher than for the CSEC group. Mortality in CREC group was significantly higher than the CSEC group (p = 0.01) and no infection group (p = 0.01).Conclusion: Many factors were discovered for acquisition of healthcare-associated CREC infection. CREC isolates were resistant to most antibiotics, and had some association with high financial burden and increased mortality. [ABSTRACT FROM AUTHOR]