OBJECTIVE:To develop a HPLC method for simultaneous determinatio n of ofloxacin and dexamethasone ac?etate in compound ofloxacin ear drops.METHODS:The analysis was carried on a XDB-C 8 ,the mobile phase was composed of methanol-potassium dihydrogen phosphate(0.02mol/L)by gradient elution,the flow rate was1.0ml/min,the column tem?perature was30℃and the detection wavelength was at240nm.RESULTS:The detectable concentrations of ofloxacin and dexamethasone acetate showed good linear correlation in the ranges of100～500?g/ml and10～30?g/ml respectively,the av?erage recoveries of ofloxacin and dexamethasone acetate were100.6%(RSD=0.46%,n=9)and101.3%(RSD=0.72%,n=9)respectively.CONCLUSION:The method is accurate and reproducible and can be used for determination of ofloxacin and dexamethasone acetate in compound ofloxacin ear drops.

Objective In order to study the pathogenesis of human papillomavirus(HPV) and seek for a therapeutic approach of the diseases caused by HPV, the construction of HPV18 E6E7 antisense RNA expressing recombinants was studied. Methods We amplified the HPV18 E6E7 816bp by PCR with HPV18 plasmid DNA as the template. pLNSX retroviruses were used as vectors,the HPV18 E6E7 retrovirus recombinants were constructed. And then the recombinants were cleaved with restriction endonuclease and hybridized with Southern blot for identifying the inserting direction and special check respectively. Results and conclusion The HPV18 E6E7 antisense RNA retrovirus expressing recombinants were screened and obtained,which had laid the foundation of studying the function of E6E7 genes further and explore whether the antisense technique can adjust and control the expression of E6E7 genes.

BACKGROUND:Human embryonic stem cels are able to self-renew indefinitely and have the capacity to differentiate into al three germ layers (ectoderm, endoderm and mesoderm). These properties imply great potential in the basic research and clinical application, including regenerative medicine, drug screening and toxins, early human embryo, cel transplantation, gene therapy,etc. However, it is a substantial chalenge to develop efficient techniques for their large-scale culture under defined conditions, and for controling and directing their differentiation. For therapeutic purposes, many scholars are trying to establish methods for maintaining pluripotency in defined xeno-free conditions and scalable culture systems. OBJECTIVE:To discuss the progress of serum-free culture systems in human embryonic stem cel research reported in recent years and to highlight the chalenges and advances being made towards the development of serum-free and xeno-free culture systems suitable for therapeutic applications. METHODS:A computer-based search of CNKI and PubMed academic database was performed for articles addressing serum-free culture systems of human embryonic stem cels published from 2008 to 2015. Repetitive and old articles were excluded. Finaly, 58 articles were summarized. RESULTS AND CONCLUSION:Several groups have attempted to exclude individual animal components by using feeder-free matrices, feeder cels of human origin, or defined xeno-free media, aiming to select a suitable matrix and medium that can minimize or not use heterologous components, in order to obtain cel lines at clinical level. However, the current cel products are far from clinical application. There are stil many problems to be solved, such as standardization, normalization and individualization of cel products. With the normative development of stem cel research and industry, human embryonic stem cel products are expected to be widely used in clinic.

In order to find an easy and rapid quantitative analytical method to detect rhamnolipid produced by Pseudomonas aeruginosa, three methods, H_ 2 SO_ 4 -anthrone analysis method, L-cysteine-H_ 2 SO_ 4 method and phenol-H_ 2 SO_ 4 method, were compared in the present paper, and the influence factors were also considered.The results showed that H_ 2 SO_ 4 -Anthrone analysis method was better than the others and its optimal reaction condition was obtained.The influence to the quantitative analysis of rhamnolipid from the residual glucose and the top clean liquid layer in the ferment solution could be ignored.But the influence from the bacterial body and the middle layer of the ferment solution reached a certain degree.Thus, the bacterial body should be removed before measuring.However, the influence from the middle layer of the ferment solution could be avoided by making a standard curve which was made by using a rhamnose mixed with the middle layer ferment solution.

Objective To prepare high-titer monoclonal antibodies against STX2A1 subunit of enterohemorrhagic E.coli(EHEC) O157∶H7.Methods BALB/c mice were immunized with GST-STX2A1 fusion protein and the spleen cells of BALB/c mice which were not immunized were used as feeder cells.Hybridoma technique,natural STX2A protein and ELISA test were used to prepare and screen the hybridoma cell lines of monoclonal antibodies against STX2A1.The ascites developed by injecting the hybridoma cells into abdominal cavity of the BALB/c mice and was purified with Protein A-Sepharose.The subclasses and isotypes were identified by mouse monoclonal antibody isotyping kit.The antigenic epitopes that can be recognized by STX2-1A3,STX2-1E10 and STX2-3A7 were analyzed by the ELISA additivity test.Results Three hybridoma cell strains were obtained and named as STX2-1A3,STX2-1E10 and STX2-3A7,respectively,all of which produced monoclonal antibodies specifically against STX2A1.The isotypes of the monoclonal antibodies were IgG1?,IgG1?,and IgG3? and the affinity constant was 5.76 ?109,1.21 ?109 and 3.97 ?108,respectively.Conclusion We have successfully prepared three hybridoma cell strains which secrete high-titer and highly specific monoclonal antibodies against STX2A1.Our study provides a basis for researching the early diagnosis,prevention and cure of the disease induced by EHEC O157∶H7.

Objective To investigate the value of serum cholinesterase (S-ChE) levels in judgment of severity and prognosis in patients with severe pneumonia. Methods The clinical data of patients with severe pneumonia, who were admitted to the Department of Internal Medicine in the First Affiliated Hospital of Sun Yat-sen University, or the Department of Neurology in the Third People's Hospital of Foshan from May 2011 to May 2015, whose hospital time was longer than 24 hours, were retrospectively analyzed. They were divided into survival group and death group according to the final outcome. Lab data, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, multiple organ dysfunction syndrome (MODS) score, the improved pneumonia score of British Thoracic Society (confusion, uremia, respiratory, blood pressure, age 65 years, CURB-65), and S-ChE levels of all patients were collected after they were hospitalized into the intensive care unit (ICU) within 24 hours. Independent risk factors for prognosis were analyzed by binary logistic regression analysis, and receiver operating characteristic curve (ROC) was plotted. Best truncation point analysis was used to compare their estimated value for prognosis of patients with severe pneumonia. Results Eighty-six patients with severe pneumonia were studied. Among them 46 patients survived, and 40 patients died. By the single factor analysis, the following lab data in the death group were found significantly lower than those in the survival group: S-ChE levels (kU/L: 2.748±0.826 vs. 4.489±1.360, t' = 7.274, P = 0.000), arterial partial pressure of oxygen [PaO2 (mmHg, 1 mmHg = 0.133 kPa): 52.55±18.29 vs. 60.83±16.65, t = 2.196, P = 0.031], oxygenation index (mmHg: 114.20±48.01 vs. 167.10±69.68, t' = 4.229, P = 0.000), and carbon dioxide combining power [CO2-CP (mmol/L): 22.85±5.44 vs. 26.00±7.63, t' = 2.225, P = 0.029]. The following clinical data were significantly higher in the death group than those in the survival group, namely body temperature (℃: 38.67±1.18 vs. 37.74±1.18, t = -3.627, P = 0.000), pulse (bpm: 130.65±15.72 vs. 107.26±19.61, t' = -6.133, P = 0.000), the ratio of concomitant chronic lung disease [45.0% (18/40) vs. 13.0% (6/46), χ2 = 10.860, P = 0.001], fraction of inspired oxygen [FiO2: 0.495 (0.410, 0.600) vs. 0.380 (0.290, 0.500), Z = -3.265, P = 0.001], APACHE Ⅱ score (25.80±5.07 vs. 16.39±5.12, t =-8.540, P = 0.000), CURB-65 score [3 (3, 4) vs. 2 (1, 2), Z = -5.562, P = 0.000], MODS score (8.15±2.49 vs. 4.35±2.01, t = -7.832, P = 0.000), international normalized ratio [INR: 1.22 (1.08, 1.31) vs. 1.07 (1.00, 1.10), Z = -4.231, P = 0.000], and activated partial thromboplastin time [APTT (s): 33.80 (32.13, 38.75) vs. 28.50 (25.70, 36.00), Z = -3.482, P = 0.000]. Binary logistic regression analysis showed that, S-ChE levels, APACHE Ⅱ score and MODS score were found to be the independent risk factors for prognosis in the patients with severe pneumonia, respectively [S-ChE: odds ratio (OR) = 0.084, 95% confidence interval (95%CI) = 0.017-0.424, P = 0.003; APACHE Ⅱ score: OR = 1.675, 95%CI = 1.098-2.556, P = 0.017; MODS score: OR = 2.189, 95%CI = 1.262-3.800, P = 0.005]. The area under ROC (AUC) for S-ChE levels, APACHE Ⅱ score and MODS score were 0.874±0.036, 0.889±0.033 and 0.884±0.035, respectively (all P > 0.05 as compared between any two means). At the best truncation points of S-ChE levels, APACHE Ⅱ score and MODS score were 3.372 kU/L, 19.5 score, and 6.5 score respectively. The sensitivity, specificity, positive predictive value and negative predictive value in predicting death risk in patients with severe pneumonia were (80.0%, 78.0%, 76.19% and 81.82%), (95.0%, 70.0%, 73.08% and 94.12%) and (70.0%, 91.0%, 87.50%, 77.78%), respectively. If S-ChE levels was combined with APACHE Ⅱ score or combined with MODS score, the sensitivity, specificity, positive predictive value and negative predictive value [S-ChE levels combined APACHE Ⅱ score: 100%, 92.0%, 93.75% and 100%; S-ChE levels combined MODS score: all 100%] were higher than single power of S-ChE levels, APACHE Ⅱ score or MODS score. Conclusions S-ChE levels can be considered as an effective and practical index to estimate the severity and prognosis in patients with severe pneumonia. The combined application of S-ChE levels and APACHE Ⅱ score or MODS score can obviously improve the prognostic power in patients with severe pneumonia.

Objective To establish a double-antibody sandwich ELISA for the rapid detection of shiga toxin typeⅡ ( StxⅡ) in shiga toxin-producing Escherichia coli ( STEC) infection. Methods A pool of murine hybridomas was used to screen out the optimal antibody pair for the establishment of double-anti-body sandwich ELISA. The established ELISA system was used to detect StxⅡin the culture supernatants of 16 clinical strains of STEC. Specificity and sensitivity of the established ELISA system were also evaluated. Results Two antibodies, S2D8 and S2C6, were successfully screened out, based on which the double-anti-body sandwich ELISA was set up. StxⅡand its variants rather than StxⅠwas detected in the culture super-natants of STEC with a lowest detection limit of 4 ng/ml. Its performance was consistent with that of commer-cial colloidal gold test kit, indicating the characteristics of good specificity and sensitivity. Conclusion The S2D8/S2C6-based ELISA laid a foundation for researches which designates the shiga toxin as a potential can-didate on the diagnosis and therapy of STEC infection.

Objective To explore the value of mast cell tryptase and brain natriuretic peptide(BNP)in the differential diagnostic of sudden death due to hypersensitivity and coronary atherosclerotic heart dis-ease.Methods Totally 30 myocardial samples were collected from the autopsy cases in the Department of Forensic Pathology, Shanxi Medical University during 2010—2015. All samples were divided into three groups:death of craniocerebral injury group, sudden death of hypersensitivity group and sudden death of coronary atherosclerotic heart disease group, 10 cases in each group. Mast cell tryptase and BNP in myocardium were detected by immunofluorescence staining and Western Blotting.Results Immunofluo-rescence staining showed that the positive staining mast cell tryptase appeared in myocardium of sudden death of hypersensitivity group and coronary atherosclerotic heart disease group. Among the three groups, the expression of mast cell tryptase showed significantly differences through pairwise comparison(P<0.05); The expression level of BNP in sudden death of coronary atherosclerotic heart disease group were significantly higher than the sudden death of hypersensitivity group and death of craniocerebral injury group(P<0.05). The difference of the expression level of BNP between the sudden death of hypersensitivity group and the death of craniocerebral injury group had no statistical significance(P>0.05).Conclusion The combined detection of the mast cell tryptase and BNP in myocardium is expected to provide help for the forensic differential diagnosis of sudden death due to hypersensitivity and coronary atherosclerotic heart disease.

Objective To study the epidemic and genetic characteristics of coxsackievirus A6 ( CVA6) strains isolated in Guangdong province.Methods Enterovirus strains positive for neither entero-virus A71 ( EV71) nor CVA16 were isolated from Guangdong province during 2008 to 2013 to screen CVA6 isolates by real-time PCR.The entire sequences of viral genes encoding VP1 of CVA6 positive samples were amplified and sequenced.The phylogenetic analysis was performed to analyze the full-length gene sequences encoding VP1 of CVA6 isolates and sequences downloaded from GenBank by using DNAStar6.0 and MEGA5.2 software packages.Results CVA6 strains accounted for 61.4%of the 1672 non-EV71 and non-CVA16 enterovirus strains isolated in Guangdong province during year 2008 to 2013.The positive rates were respectively 10.5%(4/38), 66.7%(34/51), 36.2% (81/224), 63.0% (182/289), 62.3% (325/522) and 73.0%(400/548) from 2008 to 2013 and the differences among different years were significant (χ2=133.79, P<0.01).The CVA6 isolates could be classified into four clusters in the phylogenetic tree, designated A, B, C and D (including D1, D2 and D3 subgenogroups) genogroups.The four clusters shared nucleotide diversity ranging from 15.5% to 23.1%.The CVA6 strains isolated in Guangdong province shared 88.7%-100.0% homologies in nucleotide and 95.7%-100.0% in amino acid.Subtype D2 strains circulated during 2008 to 2012 and subtype D3 strains circulated during 2009 to 2013.Conclusion CVA6 strains were the predominant enterovirus strains among non-EV71 and non-CVA16 enterovirus strains circula-ted in Guangdong province from year 2008 to 2013.The CVA6 isolates could be classified into A, B, C and D genogroups based on the sequence analysis of VP1 region.Subgroups D2 and D3 isolates were identified and the subgroup D3 isolates were the prevalent strains in Guangdong.

Objective To analyze the expression of Yes-associated protein and risk factors in differentiated thyroid carcinoma. Methods Clinical data of 152 patients with differentiated thyroid carcinoma and 27 cases of benign thyroid tumor from Changji Hui Autonomous Prefecture People’s Hospital of Xinjiang, were analyzed retrospectively. According to the expression levels of Yes-associated protein in differentiated thyroid cancer and benign thyroid tumor, univariate Chi-square test and multivariate Logistic regression methods were used to analyze the relationship between Yes-associated protein and gender, age, thyroid stimulating hormone(TSH) level, nodule size, capsule integrity, histological type and lymph node metastasis, in order to find out risk factors in differentiated thyroid cancer. Results The positive rate of expressed Yes-associated protein in benign thyroid tumor group was 66.7%(18/27), which was significantly higher than 31.58%(48/152) of differentiated thyroid cancer group, and the difference was statistically significant(χ2=12.127, P<0.01). Under an optical microscope, changes of Yes-associated protein were found to be mainly located in the nucleus and cytoplasm , and in benign thyriod tumor the degree of staining was deep, strong positive or moderately positive; differentiated thyroid carcinoma was lightly stained or no staining, weakly positive or negative. Chi-square test showed that the expression of Yes-associated protein was not affected by sex, age and pathological type(χ2= 0.419, 0.221, 0.315, all P >0.05); TSH level, nodule size, capsule integrity, lymph node metastasis had an impact on the expression of Yes-associated protein which was down regulated (χ2=4.020, 8.424, 4.386, 6.673, P<0.05 or<0.01). Logistic regression analysis showed that the nodule size was not a risk factor ( odds ratio , OR ) of Yes-associated protein expression (OR=1.929, P>0.05); TSH levels above 4.5 mU/L, lymph node metastasis and envelope incomplete were risk factors that down regulated the expression of Yes-associated protein (OR=2.167, 2.665, 3.048, all P<0.05). Conclusion Yes-associated protein is down regulated in differentiated thyroid cancer. Elevated TSH levels , incomplete capsule and lymph node metastasis are risk factors of Yes-associated protein down expression and differentiated thyroid cancer.