Objective:To establish a novel rapid HIV-1 nucleic acid detection method based on reverse transcription-recombinase aided amplification（RT-RAA）and clustered regularly interspaced short palindromic repeats（CRISPR）technology.Methods:A total of 610 full-length HIV-1 genome sequences reported in China were analyzed，and primers targeting the relatively conserved region of the HIV-1 pol gene and three crRNAs were designed. The crRNAs were validated and screened，and the CRISPR detection system was optimized to establish a “one-pot” HIV-1 RT-RAA/CRISPR assay. Ten recombinant plasmids representing HIV-1 subtypes reported in China were constructed and serially diluted to evaluate the subtype coverage and sensitivity of the assay. The specificity of the assay was evaluated using plasma samples from hepatitis B virus（HBV），hepatitis C virus（HCV）and treponema pallidum（TP）-infected individuals. The clinical performance of the assay was preliminarily evaluated using 45 clinical samples（25 plasma samples from HIV-1 infected individuals and 20 plasma samples from healthy individuals）.Results:The crRNA combination demonstrated higher sequence coverage and higher terminal fluorescence compared to single crRNA. The HIV-1 RT-RAA/CRISPR assay established with the crRNA combination could complete the detection in 30 minutes. This method could detect all 10 reported HIV-1 subtypes in China，with a sensitivity as low as 1-10 copies/μl. No cross-reactivity was observed with HBV，HCV and TP. The results of clinical sample testing were 100% concordant with those of real time fluorescence quantitative RT-PCR assay.Conclusion:This study established a novel HIV-1 RT-RAA/CRISPR nucleic acid detection method with broad subtype coverage，simplicity，rapidity，high sensitivity，and strong specificity. The method shows potential for application in point-of-care testing of HIV-1.

Objective:To establish a novel rapid HIV-1 nucleic acid detection method based on reverse transcription-recombinase aided amplification（RT-RAA）and clustered regularly interspaced short palindromic repeats（CRISPR）technology.Methods:A total of 610 full-length HIV-1 genome sequences reported in China were analyzed，and primers targeting the relatively conserved region of the HIV-1 pol gene and three crRNAs were designed. The crRNAs were validated and screened，and the CRISPR detection system was optimized to establish a “one-pot” HIV-1 RT-RAA/CRISPR assay. Ten recombinant plasmids representing HIV-1 subtypes reported in China were constructed and serially diluted to evaluate the subtype coverage and sensitivity of the assay. The specificity of the assay was evaluated using plasma samples from hepatitis B virus（HBV），hepatitis C virus（HCV）and treponema pallidum（TP）-infected individuals. The clinical performance of the assay was preliminarily evaluated using 45 clinical samples（25 plasma samples from HIV-1 infected individuals and 20 plasma samples from healthy individuals）.Results:The crRNA combination demonstrated higher sequence coverage and higher terminal fluorescence compared to single crRNA. The HIV-1 RT-RAA/CRISPR assay established with the crRNA combination could complete the detection in 30 minutes. This method could detect all 10 reported HIV-1 subtypes in China，with a sensitivity as low as 1-10 copies/μl. No cross-reactivity was observed with HBV，HCV and TP. The results of clinical sample testing were 100% concordant with those of real time fluorescence quantitative RT-PCR assay.Conclusion:This study established a novel HIV-1 RT-RAA/CRISPR nucleic acid detection method with broad subtype coverage，simplicity，rapidity，high sensitivity，and strong specificity. The method shows potential for application in point-of-care testing of HIV-1.

Total 1188 subjects aged 35-74 in an urban community of Beijing were recruited by a multistage stratified random sampling procedure. Dental caries were examined by three dentists independently. The prevalence of dental crown caries was 79. 6% (DF), that of DMFS was 24. 39% and the root caries index (RCI) was 3.5% in this group. 22. 3% of the examinees required treatment for the crown caries and 26. 0% for root caries. Bivariate correlation analysis showed that DMFS was significantly correlated with RCI (P <0. 01 ), and there was no significant difference of DMFS and RCI between males and females. The study indicates that dental caries is a common health problem in adults and elderly population of urban Beijing, and the development of community oral health service system is necessary.

Objective To investigate the effects of liposome mediated intraocular gene transfection of endostatin on the inhibition of the development of choroidal neovascularization (CNV) in a rat model. Methods Experimental CNV model in Brown Norway rats was induced by laser photocagulation. The recombinant eukaryotic expression plasmid pSecTagA hEndostatin or control plasmid pSecTagA and liposome complexes were injected into the subretinal space of the model rats. In situ hybridization and immunohistochemical observation confirmed the presence of endostatin mRNA and protein expression two weeks after injection. Intraocular and serum levels of endostatin were measured by enzyme linked immunosorbent assay. The intensity of fluorescein leakage from the photocoagulated lesions was studied at 13 d after photocoagulation. The area of CNV was measured using high molecular weight FITC dextran (MW2?10 6) for high resolution angiography in RPE choroid sclera flat mounts. In addition, sections of CNV lesions were studied by light microscopy and endoglin (CD105) immunohistochemical evaluation. Results The retina, RPE, choroidal were infected by subretinal delivery of the pSecTag hEndostatin and expressed the endostatin. Two weeks after intraocular injection, the level of endostatin in the whole eye homogenates were (50 14?3 43) ng/eye and (31 5?2 21) ng/eye, respectively. Fluorescein leakage from the CNV lesions decreased significantly as compared with that in the control groups. The average area of CNV at the sites of the Bruch's membrane rupture showed significant difference in eyes injected with endostatin as compared with that in the control eyes. Endothelial cells demonstrated strong immunoreactivity of CD105 in CNV lesions in the control eyes. Conclusion Liposome mediated endostatin gene transfection can significantly inhibit the development of CNV.

Objective:To compare the characteristics of Dean's index(DI) and tooth surface index of fluorosis(TSIF). Methods:416 inhabitants of 12, 15 and 35~44 years old were sampled randomly to receive epidemiological survey assessed by DI in fluorosis endemic areas of Xingtai City, Hebei Province. Then TSIF was used to investigate the 178 samples selected randomly from the 416 subjects. Two examiners(S/C) were trained by an experienced specialist of epidemiology(W) before investigation. SPSS 10.0 software and Excel database were used to analyze the data.Results:Weighted Kappa of theoretic calibration of DI and TSIF was ranging from 0.86 to 0.96. The results of TSIF were lower than DI in clinical calibration test. With the increase of the number of tooth surfaces concerned, strength of agreement declined, ranging from “very good” to “moderate”. Prevalence of fluorosis according to DI was lower than that accoding to TSIF.In 35-44 years old people difference of fluorosis prevalence calculating between DI and TSIF was almost 40%. The most probably reason for this phenomenon was that a person with “questionable” fluorosis wouldn't be calculated as a fluorosis patient. The proportion of “questionable” in 35-44 age group was the highest (40.3%). Conclusion:DI is suitable for large-scale epidemiology survey, and should be combined with community fluorosis index (CFI), while TSIF is suitable for esthetic study, especially for severe fluorosis patients.

Objective:To study the psychosocial effect of fluorosis on students with dental fluorosis.Methods:115 students with different types of fluorosis were sampled randomly from fluorosis epidemic area of Xingtai city in Hebei province, including 60 of 12-year-old and 55 of 15-year-old students. Dental fluorosis was classified by Dean's Index (DI). Parents and teachers of the selected students were involved in a psychosocial questionnaire investigation which included five five-point questions, respectively.Results:Prevalence of fluorosis was 89.6% in the young students in the area. Evaluation scores by parents, which included “health of teeth”, “satisfaction of teeth” and “perceived well-being”, decreased with the decline of DI. Statistical difference was found in the answer to the five questions by parents when comparing the evaluation scores of control(without dental fluorosis) group,moderate dental fluorosis group and severe dental fluorosis group(P0.05). Difference of the evaluation scores of parents and teachers on boys and girls was not significant.Conclusion:Fluorosis has psychosocial impact on students, especially evaluated by parents.