Trends of HIV/Syphilis/HSV-2 seropositive rate and factors associated with HSV-2 infection in men who have sex with men in Shenzhen, China: A retrospective study.

OBJECTIVES: To analyze the trends of HIV/syphilis/HSV-2 seropositive rate and explore the related factors with HSV-2 infection to provide the basis for adjusting STD intervention strategies and formulating prevention and control measures among MSM in Shenzhen. METHODS: Time-location sampling was conducted among MSM in Shenzhen in 2012, 2014, 2016, and 2018. Data on demographics, sexual behaviors and the laboratory test results of HIV, syphilis, HSV-2 were collected. The χ2 trend test was used to analyze the trends of HIV/syphilis/HSV-2 seropositive rate. The binary logistic regression model was used to explore the factors associated with HSV-2 infection. RESULTS: The seropositive rate of HIV fell significantly from 15.9% in 2012 to 8.7% in 2018 (Ptrend = 0.003), syphilis seropositive rate was significantly decreased from 20.4% in 2012 to 14.8% in 2018 (Ptrend = 0.025), HSV-2 seropositive rate had no significant change (16.7% in 2012 to 14.0% in 2018; Ptrend = 0.617). In principal component logistic regression analysis showed that FAC1_1 (X1 = Ever had sex with female, X2 = Gender of first sexual partner, X3 = Marital status, X4 = Age group), FAC2_1 (X5 = Education, X6 = Monthly income (RMB), X7 = Frequency of condom use in anal sex with men in the past 6 months), and FAC4_1 (X9 = History of STDs) were significantly associated with HSV-2 infection. CONCLUSIONS: The seropositive rates of HIV and syphilis have dropped significantly but are still high. HSV-2 seropositive rate had no significant change and maintained a high level. It is necessary to continue strengthening HIV and syphilis interventions among MSM in Shenzhen. HSV-2 detection and intervention are urgently required for MSM, which might be another effective biological strategy further to control the HIV epidemic among MSM in Shenzhen.

[Study on synchronous correlation between fruit characteristic spectrum and the parameter of internal quality for Hamlin sweet orange fruit].

The purpose of our study is to study the relationship between the reflective spectrum of fruit and the internal quality of the orange fruit and find the suitable mark spectrum that can synchronously measure the several fruit quality index at same time to lay a foundation for the development of a rapid and nondestructive field fruit quality analysis technique by analyzing the visible-near infrared spectrum. Mature Hamlin orange (Citrus sinensis (L)cv. Hamlin sweet orange) fruits were individually mensurated for their reflective spectrum by using FieldSpec-HH spectrometer and for their contents of total soluble solid (TSS), citric acid and vitamin C (Vc) by chemistry analysis. The experiment results showed that the fruit reflectivity values (x) at 988 nm was significantly correlated to both TSS (y)(r = 0.387* *, y = 13. 957x + 5.405), TSS/acid ratio(y)(r = 0. 440* *, y = 75.120x + 37.256), and Vc(r = 0.309*). Both of TSS and Vc contends were positively correlated with the second derivatives of the reflective spectrum at 943 nm, with correlation coefficients of 0.339* and 0.355*. TSS/acid ratio was positively correlated only with the reciprocal log values of the reflective spectrum at 944 nm (r = 0.304*). The results in this study indicated that fruit quality indexes TSS, Vc and TSS/acid can be synchronously, rapidly and nondestructively field measured at the same time by the 988 or 429 nm reflective spectrum test and special regress equation operation.