AIM: To study whether there was a correlation between central foveal thickness (CFT) assessed with optical coherence tomography (OCT) and visual acuity of patient with high myopia after phacoemulsification and intraocular lens implantation.METHODS: Totally 67 patients with high myopia underwent phacoemulsification and intraocular lens implantation were enrolled in the study.Best corrected visual acuity (BCVA) was recorded and CFT was measured using OCT at 1wk,1 and 3mo after oerations.BCVA and CFT were compared before and after the operation.All patents were divided into two groups by the BCVA at 3mo after operation,BCVA>0.5 in Group A and BCVA≤0.5 in Group B.ANOVA,Spearman correlation analysis and independent t test were used for statistical analysis.RESULTS: There was a statistically significant difference between preoperative BCVA and postoperative BCVA (F=115.04,P<0.01).Preoperative CFT was different compared with that 1wk and 1mo after operation (P=0.04,0.02) and was not different with that 3mo after operation(P=0.52).There was a statistically significant difference in CFT of postoperative 3-month compared with that of postoperative 1-week(P<0.01) or that of postoperative 1-month (P<0.01).BCVA showed significant positive correlation with CFT without foveal lesion on postoperative 3mo (r=0.28,P=0.03).CFT of Group A and Group B was significantly different at 3mo after the operation (t=-2.24,P=0.03).There was no significant difference in age and intraocular lens of two groups.CONCLUSION: Optical coherence tomography allow for objective assessment of retinal construction changes in eyes with high myopia are correlated to visual acuity.

Objective To explore the mechanism of CTL dysfunction in HCV infected person, to provide a theoretical basis for further understanding the pathogenesis of hepatitis C and the development of HCV vaccines. Methods HCV nucleopolypeptides were selected and synthesized with the method of solid phase synthesis. BALB/c mice were immunized subcutaneously with HCV nucleopolypeptides, and CTL activity of mice was detected by LDH releasing test. Results CTL of mice could be inhibited by HCV nucleopolypeptides residues 39-74, 67-76, 71-80 and enhanced by HCV nucleopolypeptides residues 5 23,63 72,131 140. Conclusion The function of CTL can be suppressed and intensified by different HCV nucleopolypeptides.

Objective To establish practical cell model of HCV infection, and investigate the susceptibility of a human liver cell line HepG2 to hepatitis C virus in vitro. Methods A human liver cell line HepG2 was incubated with serum from a chronic hepatitis C patient for 6～8 hours. Both the plus and minus strands of HCV RNA in infected cells or supernatant were examined by reverse transcription polymerase chain reaction (RT PCR). The HCV NS 3,NS 5 antigens in infected cells were respectively detected with the monoclonal antibodies to antigens of their own by immunohistochemical assay. The minus strand of HCV RNA in infected cells were localized by in situ hybridization. Results The intracellular plus or minus stands of HCV RNA were first detected on day 3 post incubation and then could be intermittently detected until day 35 post incubation in cells or supernatant. The positive signals of NS 3,NS 5 antigens could be expressed within cytoplasm of infected cells. The minus strand of HCV RNA was located within cytoplasm by in situ hybridization. Conclustions These results show that a human liver cell line HepG2 is not only susceptible to HCV but also able to support its long time replication in vitro.

Objective To investigate the pathogenesis of cytotoxic T cell (CTL) dysfunction in patients with HCV infection. Methods CTL detecting system was established. Two polypeptides which could enhance CTL function and two polypeptides which could inhibit CTL function were selected and cross-combined. BALB/c mice were immunized by subcutaneous injection of the combined polypeptides, and the CTL activity in mouse spleen cells was detected by LDH release test. Results CTL activity in BLAB/c mice immunized by polypeptides in the core region of HCV could be enhanced by CPA10 (5-23 aa) and inhibited by CPA9 (39-74 aa). CTL activity in the mice could be enhanced by polypeptides from the HCV core region, CPB2+CPB8, and CPB6+CPB8, respectively. There was no obvious difference between CPB2+CPB7, CPB6+CPB7 and the negative control. Two-factor analysis of variance showed that there was reciprocal action between the inhibitory and enhancing polypeptides from the HCV core region. Conclusion CTL activity in BLAB/c mice can be detected stably by LDH. There is an interactive effect between the inhibitory and enhancing polypeptides from the HCV core region.

Objective: To discuss the pathologic and clinical characteristics of papillary urothelial neoplasm with low malignant potential (PUNLMP). Methods: We retrospectively analyzed 41 cases of PUNLMP confirmed by pathological examination from 2003 to 2006 and selected 28 cases of urothelial papilloma and 51 cases of low-grade papillary urothelial carcinoma as control. Results: Forty one cases of PUNLMP (male 31; female 10, ranging from 33 to 87 years, average 61.6 years) were recruited in this study. Recurrence occurred in 6 cases (15%) with the mean recurrence period of 24.6 months. No progression was detected by pathological examination. Four patients had multiple tumors, among them 2 (50%) cases recurred. In 28 cases of urothelial papilloma, recurrence was observed in 1 (4%) case with no progression. In 51 cases of low-grade papillary urothelial carcinoma, 18 (35%) cases experienced recurrence and 5 cases (10%) had progressed disease. The difference in recurrence rate among the three groups was significant (P = 0.002). Conclusion: PUNLMP has its own pathologic and clinical characteristics. The term "low maligant potential" is more appropriate than "carcinoma". Long-term follow-up is needed after surgery because of high recurrence rate.

Objective To establish a simple animal model and the cytotoxic T cell(CTL) detecting system for the studies of the effects of CTL on HCV infection. Methods The CTL activity in BLAB/c mice immunized by polypeptides in the core region of HCV was detected with lactic dehydrogenase (LDH) by using SP2/O cells as the target cells. Results CTL activity in BLAB/c mice immunized by polypeptides in the core region of HCV could be detected with LDH. The activity could be enhanced by CPA10(5～23 aa) but inhibited by CPA9(39～74 aa). Conclusion CTL activity in BLAB/c mice can be detected stably by LDH.

Objective　To investigate the role of cytotoxic T lymphocyte associated molecule-4Ig(CTLA-4Ig) in the prevention of C57BL/6 mice autoimmune hepatitis. Methods　The C57BL/6 mice were intraperitoneally immunized with C57BL/6 mice liver-specific protein in complete Freund's adjuvant. At the same time CTLA-4Ig were given to observe the pathologic alteration of C57BL/6 mice liver. Results　With the increase of time of immunization, the results in the treatment group were similar to those of the control group; but inflammatory cell infiltration, hepatic cell swelling, focal necrosis and severe hepatocyte damage were found in the pathologic model group. There was a significant difference between the pathologic model group and control one. Conclusion　Autoimmune hepatitis of C57BL/6 mice can be effectively prevented by CTLA-4Ig.

Objective To analyze the common respiratory tract infection pathogens distribution and their drug resistance in pedi-atric cardiac intensive care unit(CICU),so as to provide reference for clinical rational use of antibiotics.Methods 1 350 cases of sputum specimens from lower respiratory tract infection patients of pediatric CICU in the medical center between January 2011 and December 2012 were cultivated and drug susceptibilities were tested.The results were retrospectively analyzed.Results 490 patho-genic strains were isolated from 1 350 cases of sputum specimens and identified,including Gram negative bacilli 288 strains (58.78%),Gram positive coccus 140 strains(28.57%),fungi 62 strains(12.65%,mainly Candida albicans ).Gram negative bacilli was given priority to with Klebsiella pneumoniae (62 strains,12.65%),followed by Branhamella catarhalis ,Pseudomonas aerugi-nosa and Escherichia coli .The rates of extended-spectrum beta-lactamases(ESBLs)-producing strains among Escherichia coli and Klebsiella pneumoniae were 73.33% and 66.13%,respectively.Gram positive coccus was given priority to with Staphylococcus aureus (65 strains,13.27%),followed by Streptococcus pneumoniae .Methicillin-resistant Staphylococcus aureus (MRSA)accounted for 24.62%.Conclusion Staphylococcus aureus ,Streptococcus pneumoniae and Klebsiella pneumoniae are main pathogens of re-spiratory tract infection in pediatric CICU.And there is multiple drug-resistant bacteria infection.Rational applicattion of antibiot-ics according to the test results of isolation and drug susceptibility is an effective way to control the infection of critical children and reduce the emergence of resistant strains.

Objective To study the survival and melanogenic potential of human melanocytes reversibly immortalized via SV40T antigen gene and Cre/loxP system in Guinea pigs. Methods The supernatants of retrovirus vector Cre-ERT2 were used to infect melanocytes which had been successfully transfected by SV40TAg gene (MCT), then the expression of Cre recombinase was induced with tamoxifen in infected cells; subsequently, the surviving cells, which were named as MCTC, were subjected to expansion culture. Guinea pigs were utilized to establish animal models of vitiligo, then MCTC and primary melanocytes were transplanted respectively into the animal models. The repigmentation at the transplanted area was observed with naked eyes successively until 3 months after the transplantation when tissue samples were obtained from implanted area and nonimplanted area of guinea pigs and subjected to Masson-Fontana silver stain and Hematoxylin-eosin stain for the analysis of melanocyte distribution and melanin deposition in epidermis. Results Repigmentation started 4 weeks after the transplantation, and dark or brown patches, which ranged in size from 0.5 to 1 cm, were observed in the implanted area 3 months after the transplantation. The repigmentation rate was of no significant difference between pigs transplanted with MCTC and those with primary melanocytes (82.5% vs 76.7%, P > 0.05). Pathological examination revealed melanin deposition in the basal layer of epidermis and some hair follicles in transplanted area. Conclusions SV40T antigen gene combined with Cre/loxP site-specific recombinase system can induce the reversible immortalization of human melanocytes, and the immortalized melanocytes have a favorable profile of biological safety and similarity in survival rate and melanogenic potential to primary melanocytes.

Objective To isolate melanocytes from epidermis and identify their biological characters. Methods Taking TPA/bFGF/IBMX as basic supplements in medium DMEM/F12(1∶1), the cultured cells from the resected foreskin were purified with trypsin digestion and G418 selection, and the cellular structure and function were observed by Dopa-staining, melanin content assay, tyrosinase activity assay and immunohistochemical staining. Results Dopa-staining showed that the cultured melanocytes had melanin synthesis, melanin content assay and tyrosinase activity assay showed the tyrosinase function of the cells was normal, immunohistochemical staining demonstrated the cell differentiation was normal. Conclusion Melanocytes could be cultured by TPA/bFGF/IBMX and would maintain normal structure and biological function under such conditions.