Discrepancy between behavioral-indicated and perceived candidacy for HIV pre-exposure prophylaxis among men who have sex with men in Chengdu, China / 北京大学学报(医学版)

OBJECTIVE@#To explore the discrepancy between behavioral-indicated candidacy and perceived candidacy (behavioral-perceived gap) and its associated factors of human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) among men who have sex with men (MSM), so as to identify the focus population of PrEP interventions and to design and implement targeted interventions.@*METHODS@#We recruited a sample of 622 HIV-negative MSM who were regular clients of a community-based organization located in Chengdu, China, from November to December 2021. A cross-sectional questionnaire was used to collect the participants' information on social demographics, PrEP-related knowledge and cognitions, and risk behaviors. In this study, behaviorally eligible for PrEP was defined as performing at least one type of high-risk behavior in the past six months, including inconsistent condom use, sex with an HIV-positive partner, confirmed sexual transmitted infections (STI) diagnosis, substance use, and post-exposure prophylaxis (PEP) experience. Logistic regression models were fitted, and multivariate analyses were adjusted for social demographics.@*RESULTS@#Among the 622 eligible participants, 52.6% (327/622) were classified as behaviorally eligible for PrEP. Only 37.9% (124/327) of the participants perceived themselves as appropriate candidates for PrEP and 62.1% (203/207) had discrepancy between behavioral-indicated and perceived candidacy. 85.9% (281/327) had heard of PrEP, and 14.2% (40/281) accessed PrEP information through health care providers. Of the 327 participants eligible for behavior-indicated PrEP use, about half (47.1%) knew how to obtain PrEP medication and 33.0% had a professional PrEP counseling experience. The majority (93.3%) had no or few friends using PrEP. 54.1% scored eight or above in PrEP knowledge level. 66.7% reported having two or more sexual partners in the past six months. After adjusting for age and recruitment channel, we found six factors that were associated with perceived candidacy for PrEP, including PEP use [adjusted odds ratio (ORA)=2.20; 95% confidence interval (CI): 1.33-3.63], PrEP availability (ORA=1.69; 95%CI: 1.06-2.68), a greater number of PrEP-using friends (ORA=4.92; 95%CI: 1.77-13.65), PrEP know-ledge (ORA=2.21; 95%CI: 1.38-3.56), multiple sexual partnership (ORA=1.77; 95%CI: 1.07-2.94), and perceiving a higher risk of HIV infection (ORA=4.02; 95%CI: 1.73-9.32). Substance use during sex and PrEP information channel were not statistically associated with this beha-vioral-perceived gap.@*CONCLUSION@#We observed a high discrepancy between behavioral-indicated and perceived candidacy for PrEP among Chengdu MSM in China. Future PrEP implementation efforts should be made in skills training in assessing HIV infection risk, increasing PrEP knowledge, providing professional PrEP counselling, and fostering PrEP support environment.

Association between response to repeated negative HIV testing and risk sexual behaviors in men who have sex with men in Chengdu / 中华流行病学杂志

Objective: To investigate the association between the response to repeated negative HIV testing and the risk sexual behaviors in men who have sex with men (MSM) in Chengdu. Methods: A total of 610 MSM were recruited by convenience sampling method through Chengdu Tongle Health Consultation Service Centre from March to May 2022. Data were collected from the MSM through questionnaire survey, including the demographic characteristics, sexual behaviors in the past 6 months, the response to rerpeated negative HIV testing. Univariate and multivariate logistic regression models were conducted to analyze the association between the response to repeated negative HIV testing and risk sexual behavior. Results: A total of 579 (94.9%) participants participated in the questionnaire survey and 354 (61.1%) subjects were included in the study.For the negative HIV testing, some MSM believed that they had taken effective protection measures (17.03±2.20), some believed that they were lucky (7.50±1.87) and some believed that they were at low risk (8.87±3.62). Multivariate logistic regression model showed that protected sexual behavior was negatively associated with group sex (aOR=0.80, 95%CI: 0.67-0.95), lucky was positively associated with casual sex (aOR=1.20, 95%CI: 1.06-1.35), inconsistent condom use (aOR=1.21, 95%CI: 1.06-1.37), group sex (aOR=1.26, 95%CI: 1.00-1.60), and multiple sexual partners (aOR=1.24, 95%CI: 1.09-1.42) and low risk perception was positively associated with multiple sexual partners only (aOR=1.08, 95%CI: 1.01-1.15). Conclusions: There were high levels of recognition of protected sexual behavior and lucky dimensions in response to repeated negative HIV testing and well risk perception in MSM in Chengdu. In HIV testing and counseling services, intervention and risk warning should be strengthened in MSM who believed that they are lucky to improve their awareness of safe sex and reduce the negative effects of fluke mind.

Relationship of urine cobalt and individual exposure levels of cobalt and its compounds in cobalt exposed workers / 中国职业医学

@#Objective - To analyze the relationship between cobalt level of post shift urine and individual exposure level of ， cobalt and its compounds in cobalt exposed workers and to explore the feasibility of using urine cobalt as a biomarker. Methods - A total of 148 occupational cobalt exposed workers from a new material company were selected as the exposed ， - - group and 44 non occupational cobalt exposed workers from the company were selected as the control group using the typical sampling method. The exposure concentration of time weighted average of cobalt and its compounds in the workplace air of the - two groups was determined by inductively coupled plasma mass spectrometry as the individual exposure level. The cobalt levels - - of pre shift and post shift urinary samples of the two groups were detected by this method. The linear relationship between the - cobalt level of post shift urine and the individual exposure level of cobalt and its compounds in the air of the workplace was Results - 3 analyzed. The individual exposure level of cobalt and its compounds in the exposed group was 1.10 131.71 μg/m with （M） 3 the median of 12.23 μg/m. No cobalt and its compounds were detected in the workplace air in the control group. The cobalt - - levels of pre shift and post shift urines in exposed group were higher than those in the control group at the same time point （M： vs ， vs ， P ） - - 1.54 0.56 μg/L 8.77 0.83 μg/L all <0.01 . The cobalt level of post shift urine was higher than that in pre shift （M： vs ，P ）， urine in the exposed group 8.77 1.54 μg/L <0.01 and it was positively correlated with the individual exposure level （ ，P ） ， of cobalt and its compounds Spearman correlation coefficient=0.86 <0.01 . After common logarithm conversion the linear regression equation of the cobalt level of post shift urine and the common logarithm of individual exposure level of cobalt and （x） ：ŷ x（ ；F ， its compounds in the exposed group was as follows = −0.178 + 0.988 coefficient of determination=0.72 =374.75 P ；t ， P ） Conclusion - <0.01 = - 19.36 <0.01 . There was a linear correlation between cobalt level of post shift urine and occupational cobalt exposure level of cobalt exposed workers. Urinary cobalt can be used as a biomarker of occupational cobalt

Applicability of three surveillance methods for Aedes albopictus in dengue risk indication / 中华疾病控制杂志

Objective To disscus the applicability of three surveillance methods for Aedes albopictus in dengue risk indication. Methods Larval and adult mosquito surveillance were conducted in two villages of Guangzhou by using three vector monitoring methods. Meteorological data and dengue cases were obtained in the same period. Results The population dynamics of larvae and adult mosquitoes were affected by temperature and their overall trend was consistent, but there were differences between the abundance of larvae and adult mosquitoes. From December to February the next year, Breteau index(BI) ranged from 5.66 to 24.53 with a risk of level 1 to 3 for dengue fever, while the mosquito and oviposition positive index(MOI) and adult-mosquito density index(ADI) were 0 to 4.00 and 0 to 1 per man-hour, respectively, indicating no risk for dengue fever. In March, compared with BI which indicated a risk of level 3, MOI were 2.13 and 3.77, respectively, representing for no risk. ADI were 4 to 6 per man-hour, indicating a risk of level 1 and level 2, respectively. After April, the dengue risk level reflected by each indicator became to be consistent. Conclusions The risk of dengue fever indicated by BI is always higher than or equal to the risk indicated by the other two. Compared with BI, MOI and ADI are more sensitively in reflecting the activity of Ae. albopictus.

Effect of monoclonal antibodies against LI-cadherin on the proliferation of human hepatocellular carcinoma cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To obtain monoclonal antibodies (mAb) against LI-cadherin and investigate their effects on the proliferation of human hepatocellular carcinoma cells.</p><p><b>METHODS</b>Balb/c mice were immunized with recombinant LI-cadherin, and hybridoma cell lines secreting monoclonal antibodies against LI-cadherin were established with routine cell fusion and subcloning approach. The specificity of these mAbs was determined by enzyme-linked immunosorbent assay (ELISA) and Western blotting. The effect of the mAbs obtained on the growth of HepG2 cells was assessed using inverted microscope and MTT assay.</p><p><b>RESULTS</b>Two hybridoma cell lines (F001 and F002) stably secreting specific mAbs were obtained. Western blot analysis showed that the two antibodies specifically recognized LI-cadherin antigen derived from human eucaryotic cells or tissue. Treatment of the HepG2 cells with the mAbs resulted in reduced viable cell number and changes in the cell morphologies, and the two mAbs inhibited the proliferation of HepG2 cells in a concentration-dependent manner (P<0.05).</p><p><b>CONCLUSION</b>The two specific mAbs obtained can inhibit the proliferation of HepG2 cells in vitro, which facilitates further study of the relationship between LI-cadherin and tumors.</p>

Isolation and identification of Sclerotinia stem rot causal pathogen in Arabidopsis thaliana / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

A new stem rot disease is found to occur naturally on Arabidopsis plants in greenhouses of Fuzhou, China. In order to identify its pathogen, we conducted a series of fungal isolation and purification, plant reinoculation, and ascus and ascospore induction from the sclerotia. The isolate caused typical water-soaked lesions after reinoculation and produced sclerotia both on Arabidopsis plants and culture medium plates, and the sclerotia could be induced to produce discal apothecia and 8 binucleate ascospores per ascus. These disease symptom and fungal morphology data revealed that the fungus Sclerotinia sclerotiorum (Lib.) de Bary was the pathogen for Arabidopsis stem rot. To confirm this, we further amplified its large subunit ribosomal DNA (LSU rDNA) by polymerase chain reaction (PCR), and compared the sequence with the known LSU rDNA sequences in GenBank. The results show that the sequence shares the highest identities with the LSU rDNAs of different S. sclerotiorum strains. Taking all these data together, we concluded that the fungus that caused the Arabidopsis stem rot is S. sclerotiorum (Lib.) de Bary. This is the first report that Arabidopsis is naturally infected by S. sclerotiorum.