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.

Aim To investigate the protective effects of dihydroquercetin(DDQ) against myocardial ischemis reperfusion injury(MIRI) in rats.Methods Male Sprague-Dawley rats were randomly divided into 4 groups(n=10):normal,control,I/R model, and I/R model+DDQ(5,10 mg·L-1).This study used an isolated Langendorff rat heart model.The left ventricu-lar developed pressure(LVDP),heart rate(HR) and the maximum rise and fall rate of the left ventricular pressure(±dp/dtmax) were monitored and documented using a physiological recorder.The levels of lactate dehydrogenase(LDH) and creatine kinase(CK) were analyzed using enzyme-linked immunosorbent assay(ELISA).Infarct size was measured using 2,3,5-triphenyltetrazolium chloride staining.The levels of superoxide dismutase(SOD) and malondialdehyde(MDA), as well as the ratio of glutathione/glutathione disulfide(GSH/GSSG) were measured via ELISA.HE staining was used to observe the pathological changes of myocardial tissue.Results Compared with the I/R model group, the I/R model+DDQ groups raised hemodynamic parameters, SOD level, and GSH/GSSG ratio;and reduced the amount of CK, LDH, MDA levels.Moreover, the I/R model+DDQ groups had lower infarct size and pathological changes in myocardial tissue than I/R model group.Conclusion DDQ exertes cardioprotective effects against I/R via improving the oxygen free radical scavenging ability, the inhibition of oxygen free radical and reducing lipid peroxidation.