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Background: Chlamydia is common among women of reproductive age and can cause serious health issues. This study aimed to examine the trends and factors linked to newly diagnosed and reported chlamydia cases in women aged 15–49 in Guangdong Province from 2006 to 2020. Methods: We included all newly diagnosed and reported chlamydia cases from January 1, 2006, to December 31, 2020. Data from 21 cities in Guangdong Province were sourced from the National Notifiable Infectious Disease Reporting Information System in China. Temporal trends were analyzed using Joinpoint regression models. City-level factors (population density, net migration rate, and male-to-female sex ratio) were derived from the Guangdong Statistical Yearbook and the Guangdong Health and Family Planning Statistical Yearbook. Quasi-Poisson regression models were used to explore the relationship between sociodemographic factors and chlamydia incidence. Results: From 2006 to 2020, 523,367 new chlamydia cases were reported among women of reproductive age in Guangdong. The mean reported rate was 122.6 per 100,000 population over 15 years, significantly increasing from 1.4 in 2006 to 179.7 in 2020 (average annual percent change [AAPC] = 47.4%, 95% CI: 42.8%-52.2%, P < 0.05). The highest rate was 196.8 per 100,000 population in 2019. Among older women, 9,045 cases were reported, with a mean reported rate of 4.9 per 100,000, rising significantly from 0.01 in 2006 to 9.6 in 2020 (AAPC = 52.6%, 95% CI: 30.3%-78.8%, P < 0.05). The reported rate among women of reproductive age correlated with the net migration rate (RR = 1.2; 95% CI: 1.2–1.3) and the ratio of those participating in child-bearing insurance to the permanent population (RR = 1.5; 95% CI: 1.4–1.6). Conclusion: The reported rate of new chlamydia cases among women of reproductive age was significantly higher than among older adults and increased markedly from 2006 to 2020. These findings underscore the urgent need for targeted prevention strategies for women of reproductive age. [ABSTRACT FROM AUTHOR]

Background The global resurgence of syphilis necessitates vaccine development. Methods We collected ulcer exudates and blood from 17 participants with primary syphilis (PS) and skin biopsies and blood from 51 patients with secondary syphilis (SS) in Guangzhou, China, for Treponema pallidum subsp pallidum (TPA) quantitative polymerase chain reaction, whole genome sequencing (WGS), and isolation of TPA in rabbits. Results TPA DNA was detected in 15 of 17 ulcer exudates and 3 of 17 blood PS specimens. TPA DNA was detected in 50 of 51 SS skin biopsies and 27 of 51 blood specimens. TPA was isolated from 47 rabbits with success rates of 71% (12/17) and 69% (35/51), respectively, from ulcer exudates and SS bloods. We obtained paired genomic sequences from 24 clinical samples and corresponding rabbit isolates. Six SS14- and 2 Nichols-clade genome pairs contained rare discordances. Forty-one of the 51 unique TPA genomes clustered within SS14 subgroups largely from East Asia, while 10 fell into Nichols C and E subgroups. Conclusions Our TPA detection rate was high from PS ulcer exudates and SS skin biopsies and over 50% from SS blood, with TPA isolation in more than two-thirds of samples. Our results support the use of WGS from rabbit isolates to inform vaccine development. [ABSTRACT FROM AUTHOR]

Background: Chlamydia and gonorrhea notifications are rapidly rising in men who have sex with men (MSM). Currently, there are limited data on the prevalence of chlamydia and gonorrhea across various anatomical sites. Our study aimed to explore the prevalence, association and changing trends of urethral and rectal chlamydia and gonorrhea among MSM in Guangdong Province, China. Methods: We analyzed data among MSM attending sexually transmitted infections (STI) clinics in the Guangdong governmental sentinel network between 2018 and 2022. Chi-square tests were used to compare the difference, Join-point regressions for analyzing changing trends, and multivariate logistic regressions for examining associated factors. Results: We included 4856 men in the analysis. Rectal chlamydia significantly increased from 13.8% to 26.4% over the past 5 years (average annual percentage change [AAPC] 19.2%, 95%CI 1.0-40.6, p = 0.043). After adjusting for covariates, chlamydia infection positively associated with main venue used to seek sexual partners (aOR = 2.31, 95%CI 1.17–4.55), having regular sexual partners in the past 6 months (aOR = 3.32, 95%CI 1.95–5.64), receiving HIV counselling and testing services (aOR = 2.94, 95%CI 1.67–5.17), receiving peer education (aOR = 1.80, 95%CI 1.14–2.83), infection with syphilis (aOR = 2.02, 95%CI 1.02–4.01) and infection with gonorrhea (aOR 7.04, 95% CI 3.01–16.48). Gonorrhea infection positively associated with having regular sexual partners in the past 6 months (aOR = 3.48.95%CI 1.16–10.49), and infection with chlamydia (aOR 7.03, 95% CI 2.99–16.51). Conclusions: To conclude, our findings reveal a high prevalence of chlamydia infections among MSM, particularly in the rectal area. Comprehensive chlamydia and gonorrhea health services are necessary for MSM to improve sexual health. [ABSTRACT FROM AUTHOR]

Simple Summary: Ivermectin (IVM), a macrolide insecticide, targets the ionotropic gamma-aminobutyric acid receptor (iGABAR) and plays a crucial role in controlling Aedes aegypti mosquitoes and researching mosquito drug resistance. This study marks the first characterization of the GRD subunit (Ae-GRD) of the Ae. aegypti iGABAR. We discovered that the expression of Ae-GRD is negatively regulated by miR-71-5p, a finding supported by both in vitro cell studies and in vivo microinjection experiments. Using RNA interference (RNAi) techniques and bioassays, we found that silencing Ae-GRD through dsRNA microinjection decreased the susceptibility of Ae. aegypti to IVM. Additionally, similar regulation of Ae-GRD by miR-71-5p altered the sensitivity of the mosquitoes to the insecticide. iGABAR, a member of the Cys-loop ligand-gated ion channel superfamily, is a significant target of the insecticide ivermectin (IVM). GRD is the potential subunit of the insect iGABAR. However, little information about GRD in Ae. aegypti has been reported. In this study, we involved cloning and characterizing the iGABAR subunit GRD of Ae. aegypti (Ae-GRD). Sequence analysis indicated that Ae-GRD, as part of the cysteine-loop ligand-gated ion channel family, is similar to other insect GRD. RNA interference (RNAi) was employed to explore IVM resistance in Ae. aegypti, resulting in a significant reduction in Ae-GRD expression (p < 0.05), and the mortality of Ae. aegypti adults with Ae-GRD knockdown was significantly decreased after exposure to ivermectin. Bioinformatics prediction identified miR-71-5p as a potential regulator of Ae-GRD. In vitro, dual-luciferase reporter assays confirmed that Ae-GRD expression was regulated by miR-71-5p. Microinjection of miR-71-5p mimics upregulated miR-71-5p expression and downregulated Ae-GRD gene expression, reducing mortality by 34.52% following IVM treatment. Conversely, microinjection of a miR-71-5p inhibitor decreased miR-71-5p expression but did not affect the susceptibility to IVM despite increased Ae-GRD expression (p < 0.05). In conclusion, Ae-GRD, as one of the iGABA receptor subunits, is a potential target of ivermectin. It may influence ivermectin resistance by modulating the GABA signaling pathway. The inhibition of Ae-GRD expression by miR-71-5p decreased ivermectin resistance and consequently lowered the mortality rate of Ae. aegypti mosquitoes. This finding provides empirical evidence of the relationship between Ae-GRD and its miRNA in modulating insecticide resistance, offering novel perspectives for mosquito control strategies. [ABSTRACT FROM AUTHOR]

Author(s): Cheng Wang, Jason J. Ong, Peizhen Zhao, Ann Marie Weideman, Weiming Tang, M. Kumi Smith, Michael Marks, Hongyun Fu, Weibin Cheng, Fern Terris-Prestholt, Heping Zheng, Joseph D. Tucker, Bin [...]

Author(s): Cheng Wang 1,2,*, Jason J. Ong 3,4, Peizhen Zhao 1,2, Ann Marie Weideman 5,6, Weiming Tang 1,2,7, M. Kumi Smith 8, Michael Marks 3, Hongyun Fu 9, Weibin Cheng [...], Background Low syphilis testing uptake is a major public health issue among men who have sex with men (MSM) in many low- and middle-income countries. Syphilis self-testing (SST) may complement and extend facility-based testing. We aimed to evaluate the effectiveness and costs of providing SST on increasing syphilis testing uptake among MSM in China. Methods and findings An open-label, parallel 3-arm randomized controlled trial (RCT) was conducted between January 7, 2020 and July 17, 2020. Men who were at least 18 years of age, had condomless anal sex with men in the past year, reported not testing for syphilis in the last 6 months, and had a stable residence with mailing addresses were recruited from 124 cities in 26 Chinese provinces. Using block randomization with blocks of size 12, enrolled participants were randomly assigned (1:1:1) into 3 arms: standard of care arm, standard SST arm, and lottery incentivized SST arm (1 in 10 chance to win US$15 if they had a syphilis test). The primary outcome was the proportion of participants who tested for syphilis during the trial period and confirmed with photo verification and between arm comparisons were estimated with risk differences (RDs). Analyses were performed on a modified intention-to-treat basis: Participants were included in the complete case analysis if they had initiated at least 1 follow-up survey. The Syphilis/HIV Duo rapid test kit was used. A total of 451 men were enrolled. In total, 136 (90·7%, 136/150) in the standard of care arm, 142 (94·0%, 142/151) in the standard of SST arm, and 137 (91·3%, 137/150) in the lottery incentivized SST arm were included in the final analysis. The proportion of men who had at least 1 syphilis test during the trial period was 63.4% (95% confidence interval [CI]: 55.5% to 71.3%, p = 0.001) in the standard SST arm, 65.7% (95% CI: 57.7% to 73.6%, p = 0.0002) in the lottery incentivized SST arm, and 14.7% (95% CI: 8.8% to 20.7%, p < 0.001) in the standard of care arm. The estimated RD between the standard SST and standard of care arm was 48.7% (95% CI: 37.8% to 58.4%, p < 0.001). The majority (78.5%, 95% CI: 72.7% to 84.4%, p < 0.001) of syphilis self-testers reported never testing for syphilis. The cost per person tested was US$26.55 for standard SST, US$28.09 for the lottery incentivized SST, and US$66.19 for the standard of care. No study-related adverse events were reported during the study duration. Limitation was that the impact of the Coronavirus Disease 2019 (COVID-19) restrictions may have accentuated demand for decentralized testing. Conclusions Compared to standard of care, providing SST significantly increased the proportion of MSM testing for syphilis in China and was cheaper (per person tested). Trial registration Chinese Clinical Trial Registry: ChiCTR1900022409.

Background Female sex workers (FSW) are particularly vulnerable to chlamydia and gonorrhea infections. However, there were few studies that detail the evolving patterns of chlamydia and gonorrhea among Chinese FSW. Therefore, our study endeavors to assess the prevalence of chlamydia and gonorrhea epidemics within FSW, investigate their changing trends and scrutinize associated factors. Methods In 2019, China instituted a sentinel surveillance network focused on FSW in Guangdong Province. This network conducted an annual serial cross-sectional survey spanning from April to August. All analyses are predicated on surveillance data accumulated between 2019 and 2022. Results The prevalence of chlamydia increased from 10.1 to 12.3%, exhibiting an annual percentage shift of 6.8%. Conversely, the prevalence of gonorrhea dwindled from 2.0 to 1.3%, marking an annual percentage decline of 13.4% (P <  0.001). After adjusting for covariates, chlamydia exhibited associations with having household registration in other provinces (adjusted odds ratio (aOR = 0.55)), displaying symptoms of sexually transmitted infections (STIs) (aOR = 1.65) and infected with gonorrhea (aOR = 5.68). In parallel, gonorrhea demonstrated associations with providing oral sex to clients (aOR = 3.74), manifesting STIs symptoms (aOR = 4.27) and those infected with chlamydia (aOR = 5.43). Conclusions Our observations underscore the imperative to implement a comprehensive intervention strategy concentrating on chlamydia, while simultaneously fortifying endeavors to expand the scope of gonorrhea prevention services. [ABSTRACT FROM AUTHOR]

The char-CO2 reaction behaviour is important for oxy-fuel combustion of coal gangue and weathered coal or biomass. The thermal conversion characteristics of coal gangue, weathered coal, pine sawdust and their blends in CO2/N2 atmosphere were investigated using thermogravimetric analysis, focusing on the reaction behaviour of char and CO2. The results showed that the thermal conversion of coal gangue, weathered coal and pine sawdust all had two main stages, but pine sawdust had shorter time of thermal conversion. Mass loss of coal gangue/pine sawdust blends included two obvious stages with four overlapped peaks, which was different from coal gangue/weathered coal mixtures with two separated peaks. The addition of weathered coal or pine sawdust could improve the char-CO2 reactivity of coal gangue. However, the interactions were absent for all the coal gangue/weathered coal mixtures, and interaction between coal gangue and pine sawdust was obvious during the reaction of char and CO2, which was affected by the blending ratio of pine sawdust. [ABSTRACT FROM AUTHOR]