Antimicrobial mexicanolide limonoids from the seeds of Khaya senegalensis.

Three new mexicanolide limonoids were obtained from the 90% ethanol extract of the seeds of Khaya senegalensis. Their structures were elucidated as senegalenines A-C (1-3) by analysing their 1D/2D NMR and MS spectroscopic analysis. In addition, the isolated limonoids were tested in vitro for antimicrobial potentials against 5 pathogenic microorganisms. Consequently, compounds 1-3 exhibited antimicrobial activity against the tested Gram negative bacteria at the minimum inhibitory concentration values less than 40 µg/ml.

An improved MLVF method and its comparison with traditional MLVF, spa typing, MLST/SCCmec and PFGE for the typing of methicillin-resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus (MRSA) has become an important nosocomial pathogen, causing considerable morbidity and mortality. During the last 20 years, a variety of genotyping methods have been introduced for screening the prevalence of MRSA. In this study, we developed and evaluated an improved approach capillary gel electrophoresis based multilocus variable-number tandem-repeat fingerprinting (CGE/MLVF) for rapid MRSA typing. A total of 42 well-characterized strains and 116 non-repetitive clinical MRSA isolates collected from six hospitals in northeast China between 2009 and 2010 were tested. The results obtained by CGE/MLVF against clinical isolates were compared with traditional MLVF, spa typing, Multilocus sequence typing/ staphylococcal cassette chromosome mec (MLST/SCCmec) and pulse field gel electrophoresis (PFGE). The discriminatory power estimated by Simpson's index of diversity was 0.855 (28 types), 0.855 (28 patterns), 0.623 (11 types), 0.517 (8 types) and 0.854 (28 patterns) for CGE/MLVF, traditional MLVF, spa typing, MLST/SCCmec and PFGE, respectively. All methods tested showed a satisfied concordance in clonal complex level calculated by adjusted Rand's coefficient. CGE/MLVF showed better reproducibility and accuracy than traditional MLVF and PFGE methods. In addition, the CGE/MLVF has potential to produce portable results. In conclusion, CGE/MLVF is a rapid and easy to use MRSA typing method with lower cost, good reproducibility and high discriminatory power for monitoring the outbreak and clonal spread of MRSA isolates.

Cytotoxic and antibacterial aspidofractinine alkaloids from Kopsia hainanensis.

The ethanol extract of the twigs and leaves of Kopsia hainanensis afforded six new aspidofractinine alkaloids, kopsiahainanins A-F (1-6), among which alkaloids 1 and 2 possessed a lactone bridge with novel regiochemistry. The structures of the isolated compounds were established based on 1D and 2D (1H1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated compounds were tested in vitro for cytotoxic activity against seven tumor cell lines and antibacterial activities against two Gram-positive bacteria and five Gram-negative bacteria. As a result, alkaloids 1 and 2 exhibited cytotoxic activities (IC50 values <20 µM) against all tested tumor cell lines and significant antibacterial properties (MIC values from 0.12 to 0.26 mM).

Impact of Chemotherapy Delay on Overall Survival for AML with IDH1/2 Mutations: A Study in Adult Chinese Patients.

The effect of time from diagnosis to treatment (TDT) on overall survival of patients with acute myeloid leukemia (AML) remains obscure. Furthermore, whether chemotherapy delay impacts overall survival (OS) of patients with a special molecular subtype has not been investigated. Here, we enrolled 364 cases of AML to assess the effect of TDT on OS by fractional polynomial regression in the context of clinical parameters and genes of FLT3ITD, NPM1, CEBPA, DNMT3a, and IDH1/2 mutations. Results of the current study show IDH1/2 mutations are associated with older age, M0 morphology, an intermediate cytogenetic risk group, and NPM1 mutations. TDT associates with OS for AML patients in a nonlinear pattern with a J shape. Moreover, adverse effect of delayed treatment on OS was observed in patients with IDH1/2 mutations, but not in those with IDH1/2 wildtype. Therefore, initiating chemotherapy as soon as possible after diagnosis might be a potential strategy to improve OS in AML patients with IDH1/2 mutations.