三城市呼吸系统致病菌及药物敏感的初步比较

三城市呼吸系统致病菌及药物敏感的初步比较胡海棠，蒋加洪（广东省珠海市丽珠医药研究所珠海５１９０２０）呼吸系统感染是临床常见疾病。为了解各地致病菌差异及其药物敏感性状况，本文收集了１９９３年３月至１９９４年２月一年间，广州中山医科大学附属三院、武汉同济...

Study of sensitivity of different chemotherapeutic agents on colon cancer cell line SW480

Objective:The aim of this study was to investigate the sensitivity of chemotherapeutic agents 5-FU,cisplatin(DDP) or TAXOL on colon cancer cell line SW480 with different methods,to find out the best examine time period for further study of chemotherapeutic sensitivities.Methods:The SW480 cell was treated with 5-FU(200μg/mL),DDP(150μg/mL) or TAXOL(50μg/mL) respectively for 4h,8h or 12h.MTT assay was used to examine the cell survival rate,Annexin V/PI assay was used to analysis the apoptosis rate,Western Blot assay was applied to examine the expression of apoptotic protein.Results:(1) Results of MTT assay showed that the survival rate of SW480 cells at 4h,8h or 12h was:5-FU(200μg/mL)96.0%±8.2%,85.4%±7.8%,74.4% ±10.2%(P<0.05);DDP(150μg/mL) 99.0%±6.4%,88.7%±4.7%(P<0.05),46.9%±2.6%(P<0.01);TAXOL(50μg/mL) 51.5%±4.2%(P<0.01),31.9%±3.1%,17.6%±2.3%,or blank group 97.2%±5.8%,98.7%±7.2%,97.5%±7.5% respectively.(2) The apoptosis rate of cancer cells at 4h,8h or 12h was:control group:3.4%±0.2%,6.2%±0.4%,7.0%±0.5%;5-FU(200μg/mL) 4.0%±0.3%,4.8%±0.4%,7.7%±0.7%;DDP(150μg/mL) 8.5%±0.9%,18.6%±1.6%(P<0.05),67.0%±6.2%(P<0.01);or TAXOL(50μg/mL) 32.0%±5.2%(P<0.01),76.6%±8.5%,94.0% ±8.2%,respectively.(3) Western Blot assay showed that the expression of apoptosis associated protein.PARP,X-linked inhibitor of apoptasis(XIAP),Caspase-9 and Bcl-xL were changed.Conclusion:The sensitivity of chemotherapy could be assessed by MTT assay,Annexin V/PI assay and Western Blot.The best examine time of the three chemotherapuc agents was 5-FU(200μg/mL):>12h,DDP(150μg/mL):8-12h,or TAXOL(50μg/mL):<4h.

An epidemiological study of resistant tuberculosis in Chongqing,China

Background The epidemiological characteristics of drug-resistant tuberculosis （DR-TB） is fundamental to improving the prevention and control of DR-TB. Mutations in katG315 is thought to be the most predictive molecule markers for Isoniazid （INH） resistance in Mycobacterium tuberculosis （MTB）. However, mutations to these genes have not been thoroughly studied in China, and epidemiological evidence of their expression levels are especially lacking in the southwest of China, which has a high TB burden within the population. Methods MTB isolates were obtained from patients with active pulmonary tuberculosis at the TB dispensary and Chest hospital in Chongqing city between June 2003 and June 2006. Proportion methods were used to test the sensitivity to INH, RFP, SM and EMB of cultured MTB. A total of 100 MTB isolates were also randomly selected for analysis of the molecular mutation spectrum of katG by DNA sequencing. Results Totally 1 089 MTB isolates that completed positive sputum cultures and evaluated for their sensitivity to the four first-line drugs among 2 777 patients with TB. The prevalence of DR-TB and multi-drug resistant tuberculosis （MDR-TB） were 27.7% （302/1 089） and 7.3% （79/1 089）, respectively. The resistance to anti-TB drugs was found to be highest for SM （16.3%） and INH （14.0%）. There was also a significant increase in the prevalence of resistance to RFP and EMB （P〈0.01）, and an increase in MDR-TB between June 2003 and June 2004 and between July 2005 and June 2006. The total mutation rate of katG315 was 75＂5% （37/49） in INH-resistant MTB, and mutation sites included $315T, $315N and $315I with mutation rates of 81.1% （30/37）, 13.5% （5/37） and 5.4% （2/37）, respectively No katG315 mutants were found in any of the 48 INH-sensitive MTB. Our preliminary diagnostic results suggest that mutations in katG315 may potentially serve as molecular markers that can be used to diagnose the resistance to anti-TB drug of INH. Conclusion In the Chongqing, DR-TB and MDR-TB are increasing, and are becoming key problems for tuberculosis control. The use of katG315 mutations as potential molecule markers for drug resistance to INH may help improve patient treatment and decrease the spread of the disease

Susceptibility and Inverted Hysteresis Loop of Prussian Blue Analogs with Orthorhombic Structure

The magnetic susceptibility of ternary metal Prussian blue analogues with orthorhombic structure is studied using Ising model. Within the frame work of effective-field theory with correlations, the roles of the mole fraction y, uniaxial magnetic anisotropy, transverse and longitudinal magnetic field are discussed in detabls. The temperature dependence of the magnetic susceptibility is also investigated. The interesting phenomenon of the inverted magnetic hysteresis loop has been found. The results can help to understand the experimental work of the molecule-based ferri- ferrimagnet.