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Objective To study virulence factors and drug resistance mechanism of linezolid-intermediate Enterococcus faecalis(E.faecalis) isolated from patients with bloodstream infection.Methods Two linezolid-intermediate E.faecalis strains,namely A and B,were isolated from two patients with bloodstream infection,the treatment of two patients was analyzed.The minimum inhibitory concentration (MIC) of linezolid and vancomycin were determined.The virulence genes (esp,asa1,gelE,ace,agg,efaA,cylA,and hyl) and linezolid resistance genes (domain V region of the 23SrRNA,cfr,cfr[B],optrA) were amplified by polymerase chain reaction (PCR).PCR products of domain V region of 23SrRNA gene were sequenced and analyzed.Results Symptoms of two patients who isolated two linezolid-intermediate E.faecalis strains were controlled after accepted linezolid therapy.Strains A and B were both susceptible to vancomycin(MICs were 1μg/mL and 4μg/mL respectively),teicoplain,ampicillin,and nitrofurantoin,while intermediate to linezolid(MIC were both 4μg/mL).Two strains both contained multiple virulence factors,strain A were negative for cylA and hyl,strain B were negative for hyl and esp,but positive for other virulence genes.There was G2621T mutation in domain V region of 23SrRNA in strain A,and no variation was found in strain B.Drug resistance genes of cfr,cfr(B),and optrA were all negative in both strain A and B.Conclusion In the present study,two linezolid-intermediate E.faecalis strains isolated from patients with bloodstream infection were susceptible to vancomycin and ampicillin,although the treatment of linezolid in two patients is effective,the utilization of linezolid therapy in clinical practice still needs to be cautious.The mutation of target site is a significant resistance mechanism,it is necessary for us to pay more attention to these clinical strains which are non-susceptible to such antimicrobial agents,and the treatment strategy needs further study.
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<p><b>OBJECTIVE</b>To establish New Zealand rabbit hepatoma models with VX2 cell line, and modify the hepatic artery catheterization technique.</p><p><b>METHODS</b>Forty New Zealand rabbit models bearing hepatoma were established by implanting VX2 cells into the left and right liver lobes. Two weeks after the tumor cell implantation, 26 rabbits in the experimental group underwent modified hepatic artery catheterization procedures using microsurgical technique, and 10 rabbits in the control group were catheterized with 3F micro-catheter using Seldinger technique. The VX2 hepatomas were observed before and after the catheterization with multi-slice spiral CT scan and digital subtractive angiography (DSA).</p><p><b>RESULTS</b>Tumor growth after the tumor cell implantation was confirmed in 36 rabbits by CT scans and open operations. The success rate of catheterization was 88% (23/26) in the experimental group, and 40% (4/10) in the control group. VX2 hepatomas appeared as hypointense or isointense nodules on multi-slice spiral CT, and hepatic artery angiography showed that VX2 hepatomas had homogeneous or nodular tumor staining.</p><p><b>CONCLUSION</b>The modified hepatic artery catheterization using microsurgical technique has higher success rate than catheterization with 3F micro-catheter by Seldinger technique, and significantly decreases X-ray exposure for the staff undertaking the operations.</p>
Subject(s)
Animals , Female , Male , Rabbits , Carcinoma, Hepatocellular , Pathology , Catheterization , Methods , Cell Line, Tumor , Disease Models, Animal , Hepatic Artery , Liver Neoplasms, Experimental , Pathology , Radiography, Interventional , Tomography, Spiral ComputedABSTRACT
<p><b>OBJECTIVE</b>To study the influence of HBV/P22 protein on the induced apoptosis of HepG2 cells.</p><p><b>METHODS</b>In vitro, two HepG2 strains were transfected with pcDNA3.1+ and pcDNA3.1+HBV/P22 respectively and the cells were exposed to Act D and TNF alpha for 6h and then the induced apoptosis was detected by flow cytometry (FCM) and TUNEL technique. Supernatant HBeAg was detected by Abbott reagent. The intracellular expression of HBV/P22 protein was measured by Western blot and immunochemistry. In vivo, three cell groups were inoculated into nude mice by subcutaneous injections. After two weeks, Act D and TNF alpha were injected into the tumors and then the induced apoptosis in the tissues was detected by TUNEL technique. The expression of HBV/P22 protein in the tumor tissues was detected by immunochemistry.</p><p><b>RESULTS</b>In vitro, in HepG2- pcDNA3.1+HBV/P22 cells, supernatant HBeAg was positive and intracellular HBV/P22 protein was positively expressed. The apoptosis proportion of HepG2-pCDNA3.1+HBV/P22 cells was markedly lower than HepG2 and HepG2-pcDNA3.1+ cells (P < 0.05). In vivo, HBV/P22 protein was expressed in the tumor tissues, and the apoptosis proportion in the group injected with HepG2-pcDNA3.1+HBV/P22 cells was markedly lower than those injected with HepG2 and HepG2-pcDNA3.1+cells (P < 0.05).</p><p><b>CONCLUSION</b>HBV/P22 protein could inhibit the induced apoptosis of HepG2 cells both in vitro and in vivo.</p>
Subject(s)
Animals , Female , Humans , Male , Mice , Apoptosis , Hep G2 Cells , Hepatitis B Core Antigens , Genetics , Hepatitis B e Antigens , Metabolism , Mice, Inbred BALB C , Mice, Nude , Transfection , Viral Core Proteins , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To study the relationship between hepatitis B virus (HBV) genotypes and liver fibrosis.</p><p><b>METHODS</b>Polymerase chain reaction-restriction fragment length polymorphism method was employed to determine HBV genotypes in 298 HBV-related liver disease patients, including 73 with hepatocellular carcinoma, 53 with liver cirrhosis, 91 with chronic hepatitis B and 82 asymptomatic HBV carriers to analyze the relationship of HBV genotypes with serum fibrous indices and serum albumin and globulin (A/G) ratio.</p><p><b>RESULTS</b>B and C genotypes were dominant in patients with HBV-related hepatic diseases in Guangdong province. The levels of serum fibrous indices were significantly higher in patients with genotype C than in those with genotype B, and the former patients also had lower A/G ratio.</p><p><b>CONCLUSION</b>Patients with HBV genotype C may sustain more serious liver injury.</p>