血流感染肺炎克雷伯菌中CRISPR-Cas系统的分布及其与毒力基因和耐药的关系

的 了解血流感染肺炎克雷伯菌中CRISPR-Cas系统的分布特征并分析其与毒力基因和耐药的关系。方法 收集非重复血流感染肺炎克雷伯菌248株，使用Vitek2-Compact全自动微生物分析系统进行菌株鉴定及药物敏感性分析，PCR检测CRISPR-Cas系统3个相关基因(CRISPR1、CRISPR2和cas1)、筛查6种常见高毒力荚膜血清型(K1、K2、K5、 K20、K54和K57)、12种毒力基因及检测13种耐药基因，用χ2检验比较携带有CRISPR-Cas系统菌株与不携带CRISPR-Cas系统菌株毒力及耐药差异。结果 CRISPR-Cas系统的检出率为29.8%(74/248)；K1型是携带CRISPR-Cas系统肺炎克雷伯菌的主要荚膜血清型，占 28.4%(21/74)；除kpn基因外，携带CRISPR-Cas系统菌株的毒力基因检出率均大于不携带CRISPR-Cas系统菌株，其中7种差异有统计学意义；除对氨苄西林耐药率达100%外，携带有CRISPR-Cas系统菌株的其他抗菌药物耐药率均小于不携带有CRISPR-Cas系统菌株，其中13种差异有统计学意义；携带CRISPR-Cas系统菌株的耐药基因阳性率小于不携带CRISPR-Cas系统的菌株，且blaKPC、blaSHV、qnrS基因差异有统计学意义。结论 高毒力荚膜血清型肺炎克雷伯菌中主要为K1型携带CRISPR-Cas系统，携带CRISPR-Cas系统的肺炎克雷伯菌相对于不携带CRISPR-Cas系统菌株的毒力基因阳性率高，耐药率低，耐药基因的阳性率低。CRISPR-Cas系统可能能降低耐药基因在肺炎克雷伯菌中的水平传播，尤其是在K1型肺炎克雷伯菌。     

In vitro dissolution and oral bioavailability study of fenofibrate nanomatrix system prepared by hot-melt extrusion

Solvent evaporation method for preparation of nanomatrix has the disadvantages, such as residual organic solvent, environmental pollution, explosion-proofing and so on. To overcome these shortcomings, a series of fenofibrate nanomatrix drug delivery system (NDDS) consisting of nano-porous silica Sylysia^®350 (S350) and pH sensitive material Eudragit^® L100-55 (EL100-55) were prepared using hot-melt extrusion (HME), and their in vitro dissolution and in vivo bioavailability were compared. Finally, the formulation with the highest in vivo bioavailability was selected as the optimized formulation for DSC and PXRD characterization. The results showed that the optimized NDDS showed a higher bioavailability than the reference formulation, although there was crystalline form drug remaining in NDDS. The relative bioavailability of the optimized formulation was 157.1% compared with the commercial product Lipanthyl^®. In addition, the relative bioavailability of the optimized formulation was 124.8% in comparison with the formulation prepared by solvent evaporation method, showing that the NDDS prepared by the HME method was effective in improving the bioavailability of fenofibrate. In conclusion, HME was a promising method to prepare NDDS.     

The relationship between supination resistance and the kinetics and kinematics of the foot and ankle during gait

BackgroundClinical tests of foot posture and mobility are not strongly related to the dynamic kinematics of the foot during gait. These measures may be more directly related to foot and ankle kinetics. The supination resistance test (SRT) is a clinical test that may more directly measure forces acting on the weightbearing foot to provide clinicians with insight about the loading of foot structures.Research QuestionWhat is the relationship between the SRT in relaxed calcaneal stance and in single-leg-stance and the kinetics and kinematics of the foot and ankle during gait?Methods10 healthy adults between the ages of 18 and 65 were recruited to participate in this study. Three-dimensional motion analysis was performed using the Oxford Foot Model during gait. The results of the SRT were compared with peak midfoot and ankle joint moments, power generation and absorption, joint angles, and peak angular velocities and accelerations. Correlation coefficients were calculated to assess the strength of relationships between these variables and the SRT.ResultsThe SRT demonstrated significant relationships with several variables. In relaxed calcaneal stance, the SRT was inversely related to maximum midfoot pronation moments (r = −0.51), maximum midfoot plantarflexion moments (rho = −0.71), and peak midfoot power generation (r = −0.61). In single-leg-stance, the SRT was significantly related to maximum midfoot plantarflexion moments (rho = −0.55) and peak midfoot power generation (r = −0.47).SignificanceThe SRT is significantly associated to several kinetic variables that quantify midfoot loading during gait. Interventions that decrease supination resistance may have the potential to increase midfoot power generation.     

2013-2017年ICU感染病原菌分布及耐药趋势分析

目的 分析重症监护病房(ICU)感染病原菌分布及其耐药趋势，为ICU有效预防与控制医院感染提供依据。方法 采用回顾性研究方法，收集我院2013-2017年综合ICU送检的25057份临床标本分离的病原菌进行细菌种类鉴定和药敏试验。结果 分离病原菌6938株，其中革兰阴性菌5513株(79.46%)，革兰阳性菌710株(10.23%)，真菌715株(10.31%)，排名前4位分别为鲍曼不动杆菌(31.65%)、肺炎克雷伯菌(15.90%)、铜绿假单胞菌(11.46%)和大肠埃希菌(6.31%)。真菌随着时间变化呈现下降后升高趋势，鲍曼不动杆菌、铜绿假单胞菌和大肠埃希菌呈现升高后下降趋势，而肺炎克雷伯菌呈现下降后升高趋势。分离出多重耐药菌1387株，前3位分别为鲍曼不动杆菌(84.21%)、肺炎克雷伯菌(8.22%)和铜绿假单胞菌(4.83%)。5年间多重耐药鲍曼不动杆菌分布率均显著高于肺炎克雷伯菌和铜绿假单胞菌(P=0)，且在2016年检出率达最高，2013和2017年检出率最低；多重耐药肺炎克雷伯菌在2017年检出率达最高，2013年检出率最低；多重耐药铜绿假单胞菌5年间差异无统计学意义(P>0.05)。结论 我院病原菌以革兰阴性菌为主，不同年份病原菌及其耐药性变化有所不同，应定期监测病原菌及其耐药性变迁，正确合理使用抗菌药物。     

Numerical Investigation of Analytical Models of Drug Flux Through Microporated Skin

In this study, drug flux through microporated skin was modeled using detailed numerical solution of the diffusion equation. The results of the modeling were compared to previously published simplified and easy to use analytical equations. Limitations and accuracy of these equations were investigated. Appropriate modifications of the equations were identified to expand them to wider practical applications when pore shape is not circular. Numerical simulations have shown a good accuracy of the new simple equations when these are used within their limits of application.