[Association of urinary cadmium level with body mass index and body circumferences among older adults over 65 years old in 9 longevity areas of China].

Objective: To investigate the association of urinary cadmium level with body mass index (BMI) and body circumferences among the older adults over 65 years old in 9 longevity areas of China. Methods: Subjects were older adults over 65 years old from the Healthy Aging and Biomarkers Cohort Study (HABCS) between 2017 and 2018 conducted in 9 longevity areas in China. A total of 1 968 older adults were included in this study. Information including socio-demographic characteristics, lifestyles, diet intake, and health status was collected by using questionnaires and physical examinations. Urine samples were collected to detect urinary cadmium and creatinine levels. Body circumferences included waist circumference, hip circumference and calf circumference. Subjects were divided into three groups (low:<0.77 µg/g·creatinine, middle:0.77-1.69 µg/g·creatinine, high:≥1.69 µg/g·creatinine) by tertiles of creatinine-adjusted urinary cadmium concentration. Multiple linear regression models were used to analyze the association of creatinine-adjusted urinary cadmium level with BMI and body circumferences. The dose-response relationship of creatinine-adjusted urinary cadmium concentration with BMI and body circumferences was analyzed by using restrictive cubic splines fitting multiple linear regression model. Results: The mean age of subjects was (83.34±11.14) years old. The median (Q1, Q3) concentration of creatinine-adjusted urinary cadmium was 1.13 (0.63, 2.09) µg/g·creatinine, and the BMI was (22.70±3.82) kg/m2. The mean values of waist circumference, hip circumference, and calf circumference were (85.42±10.68) cm, (92.67±8.90) cm, and (31.08±4.76) cm, respectively. After controlling confounding factors, the results of the multiple linear regression model showed that for each increment of 1 µg/g·creatinine in creatinine-adjusted urinary cadmium, the change of BMI, waist circumference, hip circumference, and calf circumference in the high-level group was -0.28 (-0.37, -0.19) kg/m2, -0.74 (-0.96, -0.52) cm, -0.78 (-0.96, -0.61) cm, and -0.20 (-0.30, -0.11) cm, respectively. The restrictive cubic splines curve showed a negative nonlinear association of creatinine-adjusted urinary cadmium with BMI (Pnonlinear<0.001) and negative linear associations of creatinine-adjusted urinary cadmium with waist circumference (Plinear<0.001), hip circumference (Plinear<0.001), and calf circumference (Plinear<0.001). Conclusion: Urinary cadmium level is significantly associated with decreased BMI, waist circumference, hip circumference and calf circumference among older adults over 65 years old in 9 longevity areas of China.

[Association of sleep duration and physical exercise with dyslipidemia in older adults aged 80 years and over in China].

Objective: To explore the impact of sleep duration, physical exercise, and their interactions on the risk of dyslipidemia in older adults aged ≥80 (the oldest old) in China. Methods: The study subjects were the oldest old from four rounds of Healthy Aging and Biomarkers Cohort Study (2008-2009, 2011-2012, 2014 and 2017-2018). The information about their demographic characteristics, lifestyles, physical examination results and others were collected, and fasting venous blood samples were collected from them for blood lipid testing. Competing risk model was used to analyze the causal associations of sleep duration and physical exercise with the risk for dyslipidemia. Restricted cubic spline (RCS) function was used to explore the dose-response relationship between sleep duration and the risk for dyslipidemia. Additive and multiplicative interaction model were used to explore the interaction of sleep duration and physical exercise on the risk for dyslipidemia. Results: The average age of 1 809 subjects was (93.1±7.7) years, 65.1% of them were women. The average sleep duration of the subjects was (8.0±2.5) hours/day, 28.1% of them had sleep duration for less than 7 hours/day, and 27.2% had sleep for duration more than 9 hours/day at baseline survey. During the 9-year cumulative follow-up of 6 150.6 person years (follow-up of average 3.4 years for one person), there were 304 new cases of dyslipidemia, with an incidence density of 4 942.6/100 000 person years. The results of competitive risk model analysis showed that compared with those who slept for 7-9 hours/day, the risk for dyslipidemia in oldest old with sleep duration >9 hours/day increased by 22% (HR=1.22, 95%CI: 1.07-1.39). Compared with the oldest old having no physical exercise, the risk for dyslipidemia in the oldest old having physical exercise decreased by 33% (HR=0.67, 95%CI: 0.57-0.78). The RCS function showed a linear positive dose-response relationship between sleep duration and the risk for hyperlipidemia. The interaction analysis showed that physical exercise and sleep duration had an antagonistic effect on the risk for hyperlipidemia. Conclusion: Physical exercise could reduce the adverse effects of prolonged sleep on blood lipids in the oldest old.

[Epidemiological characteristics of mpox epidemic in Guangzhou].

Objective: To understand the epidemiological characteristics of mpox epidemic in Guangzhou and provide scientific evidence for the prevention and control of the disease. Methods: Based on the mpox surveillance system in Guangzhou, suspected mpox cases with fever and rash were reported by local hospitals at all levels to centers for disease control and prevention in Guangzhou for sampling, investigation and diagnosis. Descriptive epidemiological analysis was conducted on the clinical characteristics and treatment of the mpox cases and positive detection rate reported in Guangzhou as of 24:00 on June 23. Whole genome sequencing of the virus isolates was performed using Illumina Miniseq high-throughput sequencing platform. Results: The first mpox case in Guangzhou was reported on June 10 in 2023. As of 24:00 on June 23, a total of 25 confirmed mpox cases were reported. All the mpox cases were men with a M(Q1,Q3) of 32 (26, 36) years, the majority of the cases were MSM (96.0%). The main clinical features were rash (100.0%, 25/25), lymphadenectasis (100.0%, 25/25) and fever (52.0%, 13/25). Rash usually occurred near the genitals (88.0%, 22/25). The close contacts, mainly family members (40.4%, 23/57), showed no similar symptoms, such as fever or rash. The positive rate of mpox virus in household environment samples was 30.5%. The analyses on 3 complete gene sequences of mpox virus indicated that the strains belonged to West African type Ⅱb clade, B.1.3 lineage. Conclusions: Hidden transmission of mpox virus had occurred in MSM in Guangzhou. However, the size of affected population is relatively limited, and the possibility of wide spread of the virus is low.

[Association of hs-CRP with frailty and its components among the elderly over 65 years old in 9 longevity areas of China].

Objective: To investigate the association of the levels of high sensitivity C-reactive protein (hs-CRP) with frailty and its components among the elderly over 65 years old in 9 longevity areas of China. Methods: Cross-sectional data from the Health Ageing and Biomarkers Cohort Study (HABCS, 2017-2018) were used and the elderly over 65 years old were included in this study. Through questionnaire interview and physical examination, the information including demographic characteristics, behavior, diet, daily activity, cognitive function, and health status was collected. The association between hs-CRP and frailty and its components in the participants was analyzed by multivariate logistic regression model and restrictive cubic spline. Results: A total of 2 453 participants were finally included, the age was (84.8±19.8) years old. The median hs-CRP level was 1.13 mg/L and the prevalence of frailty was 24.4%. Compared with the low-level group (hs-CRP<1.0 mg/L), the OR (95%CI) value of the high-level group (hs-CRP>3.0 mg/L) was 1.79 (1.35-2.36) mg/L. As for the components, the hs-CRP level was also positively associated with ADL disability, IADL disability, functional limitation and multimorbidity. After adjusting for confounding factors, compared with the low-level group, the OR (95%CI) values of the high-level group for the four components were 1.68 (1.25-2.27), 1.88 (1.42-2.50), 1.68 (1.31-2.14) and 1.39 (1.12-1.72), respectively. Conclusion: There is a positive association between the levels of hs-CRP and the risk of frailty among the elderly over 65 years old in 9 longevity areas of China. The higher hs-CRP level may increase the risk of frailty by elevating the risk of four physical functional disabilities, namely ADL disability, IADL disability, functional limitation and multimorbidity.

[Association of greenness, nitrogen dioxide with the prevalence of hypertension among the elderly over 65 years old in China].

Objective: To investigate the association of mixed exposure to greenness and nitrogen dioxide(NO2) and hypertension among the older adults aged 65 years and over in China. Methods: The study subjects were from the Chinese Longitudinal Healthy Longevity Survey from 2017 to 2018. A total of 15 423 older adults aged 65 years and over meeting the criteria were finally included in the study. A questionnaire survey was used to collect information on demographic characteristics, lifestyle habits and self-reported prevalence of hypertension. Blood pressure values were obtained through physical examination. The level of normalized difference vegetation index(NDVI) was measured by the Medium-resolution Imaging Spectral Radiator(MODIS) of the National Aeronautics and Space Administration(NASA). The concentration of NO2 was from China's surface air pollutant data set. Meteorological data was from NASA MERRA-2. The exposure to NDVI and NO2 for each study subject was calculated based on the area within a 1 km radius around their residence. The association between mixed exposure of NDVI and NO2 as well as their interaction and hypertension in older adults was analyzed by using the multivariate logistic regression model. The restrictive cubic spline(RCS) function was used to explore the exposure-response relationship between greenness and NO2 and the risk of hypertension in study subjects. Results: The mean age of 15 423 older adults were (85.6±11.6). Women accounted for 56.3%(8 685/15 423) and 55.6%(8 578/15 423) lived in urban areas. The mean time of residence was (60.9±28.5) years. 59.8% of participants were with hypertension. The mean NDVI level was 0.41±0.13, and the mean NO2 concentration was (32.18±10.36) µg/cm3. The results of multivariate logistic regression analysis showed that NDVI was inversely and linearly associated with the hypertension in older adults, with the OR(95%CI) value of 0.959(0.928-0.992). Compared with the T1 group of NDVI, the risk of hypertension was lower in the T3 group, with the OR(95%CI) value of 0.852(0.769-0.944), and the trend test was statistically significant(P<0.05). Compared with the T1 group of NO2, the risk of hypertension was higher in the T2 and T3 groups, with OR(95%CI) values of 1.160(1.055-1.275) and 1.244(1.111-1.393), and the trend test was statistically significant (P<0.05). The result of the RCS showed that NDVI was inversely and linearly associated with hypertension in older adults. NO2 was nonlinearly associated with hypertension in older adults. The interaction analysis showed that NDVI and NO2 had a negative multiplicative interaction on the risk of hypertension, with OR(95%CI) value of 0.995(0.992-0.997). Conclusion: Exposure to greenness and NO2 are associated with hypertension in older adults.

[A study on longitudinal changes in white matter microstructure of parents who have lost their only child based on diffusion tensor imaging and its relationship with symptoms of posttraumatic stress disorder].

Objective: To investigate the longitudinal changes of white matter microstructural based on diffusion tensor imaging in parents who lost their only child without psychiatric disorders and its relationship with symptoms of posttraumatic stress disorder (PTSD). Methods: Parents who had who lost their only child and without psychiatric disorders in Jiangsu Province, from September 2016 to March 2017, were retrospectively collected (TENP group, 32). MRI scans were performed at baseline and at the end of 5-year follow-up, and the Clinician Administered PTSD Scales (CAPS) were used for assessing the severity of symptoms. Additionally, sex, age and education level matched healthy subjects were recruited as healthy controls (control group, 27) and underwent MRI scanning using the same protocol. The differences of fractional anisotropy (FA) values between TENP group and control group at baseline were analyzed by using Tract-based spatial statistics method, and the brain areas of lateral differences were used as the regions of interest for longitudinal follow-up analysis of TENP group. Partial correlation analysis was used to evaluate the relationship between FA values changes in longitudinal differences in brain regions and CAPS scores. Results: Compared with the control group, FA values of the right cingulate gyrus, Uncinate fasciculus, superior longitudinal fasciculus, corticospinal tract, Inferior fronto-occipital fasciculus, Inferior longitudinal fasciculus and forceps major in TENP group were decreased at baseline ((0.613±0.032) vs (0.631±0.034), (0.539±0.048) vs (0.563±0.045), (0.534±0.033) vs (0.558±0.039), (0.560±0.038) vs (0.580±0.030), (0.519±0.023) vs(0.549±0.024), (0.489±0.038) vs (0.518±0.027), (0.499±0.027) vs (0.533±0.032); all P<0.05). From baseline to follow-up, scores of trauma reexperience symptoms and avoidance/numbness symptoms were decreased ((5.2±2.8) vs (8.1±4.9), (4.0±3.2) vs (6.6±5.4); all P<0.05); FA values of the right corticospinal tract, Inferior fronto-occipital fasciculus, Inferior longitudinal fasciculus and forceps major were decreased ((0.523±0.049) vs (0.537±0.049), (0.568±0.052) vs (0.590±0.050), (0.540±0.063) vs (0.559±0.059), (0.520±0.059) vs (0.547±0.059); all P<0.05); The decrease of FA values of the right Inferior fronto-occipital fasciculus and right Inferior longitudinal fasciculus was negatively correlated with the decrease of avoidance/numbness symptoms scores (r=-0.458, -0.374, respectively, all P<0.05). Conclusions: The trauma of parents who lost their only child can result in impaired microstructural integrity of white matter. As the post-traumatic time goes by, parents who have lost their only child do not develop to PTSD and other psychiatric disorders, and the clinical symptoms are alleviated, the damage of the white matter microstructure continued to progress.

[Analysis of clinical phenotype and genotype of Chinese children with disorders of sex development].

Objective: To explore the heterogeneity and correlation of clinical phenotypes and genotypes in children with disorders of sex development (DSD). Methods: A retrospective study of 1 235 patients with clinically proposed DSD in 36 pediatric medical institutions across the country from January 2017 to May 2021. After capturing 277 DSD-related candidate genes, second-generation sequencing was performed to analyzed the heterogeneity and correlation combined with clinical phenotypes. Results: Among 1 235 children with clinically proposed DSD, 980 were males and 255 were females of social gender at the time of initial diagnosis with the age ranged from 1 day of age to 17.92 years. A total of 443 children with pathogenic variants were detected through molecular genetic studies, with a positive detection rate of 35.9%. The most common clinical phenotypes were micropenis (455 cases), hypospadias (321 cases), and cryptorchidism (172 cases) and common mutations detected were in SRD5A2 gene (80 cases), AR gene (53 cases) and CYP21A2 gene (44 cases). Among them, the SRD5A2 mutation is the most common in children with simple micropenis and simple hypospadias, while the AMH mutation is the most common in children with simple cryptorchidism. Conclusions: The SRD5A2 mutation is the most common genetic variant in Chinese children with DSD, and micropenis, cryptorchidism, and hypospadias are the most common clinical phenotypes. Molecular diagnosis can provide clues about the biological basis of DSD, and can also guide clinicians to perform specific clinical examinations. Target sequence capture probes and next-generation sequencing technology can provide effective and economical genetic diagnosis for children with DSD.

[Development of Risk Assessment Index System on HIV infection among young students based on Delphi method].

Objective: To develop a Risk Assessment Index System (RAIS) on HIV infection among young students based on Delphi method and to provide individual HIV infection risk assessment, targeted prevention and control measures. Methods: Delphi method was applied to determine the index system and weight of the assessment tool through three rounds of expert consultation and overall consideration of opinions and suggestions from 19 experts. Results: The positivity coefficients of three rounds of expert consultation were 100%. The authority coefficient of experts was between 0.887 and 0.945. The Kendall's W coefficients through first, second and third round specialist consultation was 0.379, 0.329 and 0.248, respectively (all P<0.001). The coefficients of variation in the third round were all less than 0.25, indicating that experts' opinion tend to be consistent and the results are highly reliable. The HIV infection risk assessment index system among young students consisted of 7 first grade indices and 54 second grade indices, of which weight was calculated. Conclusions: The RAIS on HIV infection for young students was initially established based on Delphi method, and could be used in the development of HIV infection risk assessment tools for personalized prevention and intervention among young students. However, the reliability, validity and effect of this assessment index system need to be further evaluated.

[Cluster analysis on survey of sexual health characteristics and health education demands in young students].

Objective: To explore the difference of sexual health characteristics and demands in students in different groups, and provide the basis for targeted sexual health eduction for AIDS prevention in young students. Methods: A survey was conducted based on the requirement of health education about sexual health and AIDS prevention in young students by the education department of Guangdong province. A two-step cluster analysis was performed on the survey data obtained by convenient sampling, the variables and number of clusters included were determined by combination of analysis results and professional knowledge. The demographic characteristics, the content and form of sexual health education needed were compared among different groups. Results: Survey data of 3 884 students were collected, and six variables were used for classification: cognition or occurrence masturbation, sexual behavior, frequency of sexual information acquisition, number of acceptable sex partners and AIDS knowledge awareness rate. By these variables, the students were classified into three levels of risk groups: high risk group (46.6%), medium risk group (39.9%) and low risk group (13.5%). As for demographic characteristics, high risk group, with a median age of 19 years, had the highest proportions of boys (65.9%), students with non-heterosexuality orientation (15.2%), urban residents (58.2%), only children (30.8%) and undergraduates (54.7%). Medium risk group, with a median age of 19 years, had the highest proportions of girls (82.7%) and vocational college students (34.0%). Low risk group, with a median age of 18 years, had the highest proportions of rural residents (52.4%), non-only child (80.6%), senior high school students (41.3%), non-boarding students (17.5%) and students without internship and part-time job experience (43.2%). In terms of health education demands, high risk group had a higher demand of information about self-identity, sexual safety, sexual decision making, contraception, abortion, and sexually transmitted disease or AIDS prevention. Medium risk group paid more attention to value on love and marriage, sexual assault. Low risk group showed a higher demand of adolescent physiology knowledge. Compared with low risk group, high risk group had a higher demand of peer education, Internet/multimedia, anonymous counseling and other forms of sexual health education. The differences were significant. Conclusion: The characteristics, sexual knowledge awareness, attitude and behavior, and health education demands of young students in different groups are different, so health education materials and methods should be developed according to the characteristics of different groups to enhance the acceptance and enthusiasm of students and improve the quality of sexual health education.

[Analysis on influencing factors of HIV testing services utilization in students with self-assessed high risk of HIV infection based on Andersen's model].

Objective: To analyze the influencing factors for HIV testing services utilization in students with self-assessed high risk of HIV infection. Methods: The research framework of the influencing factors for HIV testing services utilization in students was developed based on Andersen's health services utilization behavioral model and related literature. A cross-sectional survey was performed in students with self-assessed high risk of HIV infection by an online HIV infection risk assessment tool from March to April 2019. Multiple logistic regressions were applied with hierarchical model. Results: A total of 526 students were included in the study (age: 19.30±1.19 years old), in whom 96.2% agreed that HIV testing should be received after high-risk behavior. 56.7% (298/526) had sexual behavior and the HIV testing rate was 11.0% (58/526). The HIV testing rates in students who had and had no sex behavior were 13.42%(40/298) and 7.89% (18/228), respectively. According to the results from multivariate logistic regression analysis, non-heterosexual (compared with heterosexual, OR=7.88, 95%CI: 3.98-15.61) and higher score of AIDS knowledge awareness (compared with lower score, OR=2.05, 95%CI: 1.07-3.93) in propensity factor module, and having risk sexual behavior (compared with having no risk sexual behavior, OR=2.66, 95%CI: 1.41-5.03) and having diagnosis of STD infection in hospital (compared with having no such diagnosis, OR=6.35, 95%CI: 2.21-18.27) in demand factor module, and receiving health education about AIDS prevention in the past year (compared with receiving no such health education, OR=0.29, 95%CI: 0.11-0.76) and receiving health education about AIDS testing service in the past year (compared with receiving no such health education, OR=3.67, 95%CI: 1.71-7.90) in ability factor module were the influencing factors for utilization of HIV testing services. Conclusions: The acceptance of HIV testing in students needs to be improved urgently. Propensity factors, such as their AIDS knowledge awareness and sexual orientation, and demand factors, such as having risk sexual behavior and STD infection, have obvious impacts on the utilization of HIV testing services. However, health education about AIDS prevention and HIV testing service can play a more important role in facilitating the utilization of HIV testing in students. In the future, we should further strengthen the publicity of voluntary HIV counseling and testing service in students with particular attention to girls and those with risk sexual behaviors.

[Influence of self-categorized deviation in knowledge, attitude and practice for sexual health on the willingness to seek help for corresponding problems among young students].

Objective: To evaluate the effect of "self-categorization" on decision of health preference and the influence of self-categorized deviation in knowledge, attitude and practice (KAP) on the willingness of seeking help for sexual health among young students. Methods: From March to April 2019, young students who used a WeChat applet for sexual health and HIV infection risk assessment, which is called "Detective Bear" were recruited and investigated. According to the consistency between the self-categorization of KAP for sexual health and the systematic categorization from their honest answers, the participants were allocated into three groups: consistent, low or high status, according to their judgment on sexual information acquisition, sexual attitude, and the actual number of sexual experiences. Logistic regression was used to analyze the differences in the willingness to seek help for sexual health problems between the three groups. Results: 2 009 students with an average age of (19.2±1.1) were included. 54.7% (1 099/2 009) were female, and 98.4% (1 976/2 009) were college, undergraduate or postgraduate students. 49.0% (984/2 009) were in the consistent group, 10.9% (219/2 009) had a lower self-categorization, 40.1% (806/2 009) had a higher self-categorization. Compared with the consistent group, students with lower self-categorization of KAP for sexual health were less likely to assess HIV voluntary counseling and testing (aOR=0.65, 95%CI: 0.43-0.99). However, students with higher self-categorization seemed to dislike seeking help for sexually transmitted diseases (aOR=0.76, 95%CI: 0.59-0.98). Conclusions: Deviation in self-categorization of KAP for sexual health will reduce the young students' willingness to seek help for related problems. Especially those with lower self-categorization, lack of risk consciousness, and refuse to assess counseling and testing may increase the HIV/AIDS epidemic among this population. It is necessary to strengthen the capacity of self-assessment for young students while promoting sex education.

[Design and analysis of testing results of a WeChat applet for sexual health and HIV infection risk assessment in young students].

Objective: To summarize the design and analysis of testing results of a WeChat applet, which is called "Detective Bear", for sexual health and HIV infection risk assessment in young students, and evaluate its feasibility and effectiveness. Methods: Based on self-categorization theory, by using cluster analysis and Delphi expert consulting method, the framework of WeChat applet, risk assessment index system and preventive intervention content were determined. Young students were recruited by student associations for the application test, the results of the repeated tests and the satisfaction survey were collected and analyzed. Results: The study included 393 participants who repeated the test twice and 750 participants who volunteered to participate in the satisfaction questionnaire survey. The applet contains five modules: self-role judgment, self-test, risk assessment, assessment report generation and background management. The risk assessment module contains 6 first-level indicators and 55 second-level indicators. Assessment report generation module includes role diagnosis type, radar chart of HIV sexual health KAP and intervention prescription. In 393 students who repeated the test, the awareness of AIDS to be a serious sexually transmitted disease, the epidemic trend in young students in China, with active seeking HIV testing services and caring the infected improved. The satisfaction survey showed that 75.7% of students (568/750) accepted the applet, 86.5% (649/750) agreed the evaluation report, 83.1%(623/750) thought that there were some problems, but it was easy to use, 93.3% (700/750) said they can learn something from the applet and 84.1% (631/750) satisfied with the page design. Some students thought the questionnaire was too long and somewhat difficult to complete (P<0.05), and some reported that more can be learned (P<0.05). Conclusions: The applet integrates AIDS prevention related knowledge and practice into a challenging, interesting, interactive game and provide individualized, concrete risk assessment and self-intervention for young students, which can effectively help students to improve the awareness of AIDS related knowledge and get links for access to condoms, testing and other intervention services. However, its large-scale application and long-term effect need to be further tested.

Surprisingly good thermoelectric performance of monolayer C3N.

The rapid emergence of graphene has attracted numerous efforts to explore other two-dimensional materials. Here, we combine first-principles calculations and Boltzmann theory to investigate the structural, electronic, and thermoelectric transport properties of monolayer C3N, which exhibits a honeycomb structure very similar to graphene. It is found that the system is both dynamically and thermally stable even at high temperature. Unlike graphene, the monolayer has an indirect band gap of 0.38 eV and much lower lattice thermal conductivity. Moreover, the system exhibits obviously larger electrical conductivity and Seebeck coefficients for the hole carriers. Consequently, theZTvalue ofp-type C3N can reach 1.4 at 1200 K when a constant relaxation time is predicted by the simple deformation potential theory. However, such a largerZTis reduced to 0.6 if we fully consider the electron-phonon coupling. Even so, the thermoelectric performance of monolayer C3N is still significantly enhanced compared with that of graphene, and is surprisingly good for low-dimensional thermoelectric materials consisting of very light elements.

[Incidence of unintended pregnancy within 2 years after delivery and its influencing factors in China].

Objective: To investigate the present situation of unintended pregnancy within two years postpartum and its influencing factors in China. Methods: Participants who delivered a live birth at 60 hospitals in 15 provinces in the eastern, central and western regions of China during July 2015 to June 2016 were interviewed by using structured questionnaire. Information on occurrence of unintended pregnancy within 2 years after delivery, postpartum contraceptive use, sexual resumption, breastfeeding, and women's socio-demographic characteristics, and so on, were collected. Life-table analysis, cluster log-rank tests and a 2-level Cox regression model were used for data analysis. Results: A total of 18 045 postpartum women were investigated. The cumulative 1- and 2-year unintended pregnancy rates after delivery were 5.3% (95%CI: 4.5%－6.1%) and 13.1% (95%CI: 11.3%－14.8%), respectively. Cox regression model analysis showed that the risk of unintended pregnancy within 2 years postpartum were increased in younger women, ethnic minorities, women with abortion history, and those who had a vaginal delivery with short lactation time and late postpartum contraceptive initiation (all P<0.01). The risk of postpartum unintended pregnancy was not associated with geographic regions and hospitals where women gave a birth (all P>0.05). Conclusions: In China, the risk of unintended pregnancy within 2 years after delivery is relatively high. Service institutions and service providers should improve the quality of postpartum family planning services, promote the use of high effect contraceptive methods, and educate women to use a method at the time of their sexual resumption or even before.

[Genotypes and phenotypes of nine Uygur children with osteogenesis imperfecta in Xinjiang].

Objective: To explore the genotypes and phenotypes of osteogenesis imperfecta (OI) in Xinjiang Uygur children. Methods: The history of nine Uygur children with OI who were hospitalized in First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2017 were retrospectively reviewed. They were classified into 4 types according to the classical Sillence classification. The genes associated with OI were detected, and the pathogenic variation was assessed by InterVar and Alamut software according to the American College of Medical Genetics and Genomics (ACMG) recommendations. The phenotypes of children with different genotypes were further analyzed. Results: Nine cases aged 3 years and 6 monthes to 15 years were all clinically diagnosed as OI, the clinical manifes tations were repeated fractures, skeletal deformities,short stature, blue sclera, abnormol hearing, hypoplasia of dentin, and relaxation of Joint ligaments, among whom 6 was type Ⅲ OI, 3 were type Ⅳ OI. Nine mutations in 3 genes (COL1A1, COL1A2, and SERPINF1) were detected, and 5 of them were first reported and were all pathogenic variations. Conclusions: The cinical phenotypes of osteogenesis imperfecta in Xinjiang Uygur are complex and varied, but all of them have fractures and skeletal deformities. Genotype is different from that reported at China and abroad, and the SERPINF1 gene may have a higher incidence in Uyghur population. The genetic heterogeneity and unique gene variation pedigree of Uyghur osteogenesis imperfecta defects further provide a basis for the correlation between genotype and phenotype of osteogenesis defects.

[Status quo and characteristic analysis among MSM-users of the "Internet Plus-based AIDS Comprehensive Prevention Service System" in Guangzhou].

Objective: To analyze the characteristics of the "Interner Plus-based AIDS Comprehensive Prevention Service System" among MSM who frequently using the Internet in Guangzhou. Methods: An online survey was conducted among MSM who were recruited through gay-website portals between August and September, 2018 in Guangzhou, to collect information regarding the use of and attitudes on the "Interner Plus-based AIDS Comprehensive Prevention Service System" . Logistic regression was used to explore the association between the use of Internet intervention tools and related behavioral characteristics. Information on the awareness of AIDS, HIV testing, and condomless anal sex behavior were compared between the core or non-core services users. Results: A total of 777 Internet-based MSM were recruited as participants including 638 men (82.1%) as core service users. MSM were satisfied in using the the "Interner Plus-based AIDS Comprehensive Prevention Service System" while more than 80.0% of the users felt that the tools were helpful in: increasing the HIV awareness, promoting test uptake, and reducing those related risk behavior. Comparing with those who did not use the tools, the users showed higher rates in practising condomless anal intercourse (1.50-1.86 times), commercial sex with men (11.60-21.21 times), and unprotected vaginal intercourse (13.62-20.67 times), in the last 6 months. Proportions of core service users appeared as: [96.6% vs. 74.8%, aOR (95%CI): 8.80 (4.85-15.97)] on HIV testing, [56.4% vs. 22.3%, aOR (95%CI): 4.54 (2.94-7.02)] on regular HIV testing and [86.2% vs. 80.6%, aOR (95%CI): 1.75 (1.06-2.89)] on awareness of HIV knowledge respectively, which were all significantly higher than the non-core service users. Conclusions: The frequent Internet using MSM in Guangzhou claimed to have had high acceptance and satisfaction on the local Internet HIV intervention service tools. The "Internet Plus-based AIDS Comprehensive Prevention Service System" had effectively reached the high-risk subgroups of MSM, increasing the awareness on related risk and promoting testing on HIV.

[Characteristic analysis among MSM-users of the "Online HIV Acquisition Risk Assessment System" in Guangzhou].

Objective: To analyze the characteristics of levels related to the risk through self-evaluation system, among MSM users in Guangzhou, between 2015 and 2017. Methods: Between 2015 and 2017, data was collected from the users of a self-evaluation system network related to HIV infection, based on the previous 'HIV health risk appraisal model'. Information on risk factors was collected to calculate the scores and levels of risks and to estimate the incidence of HIV. Taking the reference of R value on risks as (R=0.9-1.1) in general population. The ones with very low risk, with low risk, moderate risk, high risk and very high risk were set as R≤0.5, 0.52.0, respectively. The scores of modifiable risk factors were compared with different subgroups of MSM. Results: A total of 4 601 MSM were involved in this study, with the following features presented as: aged 16-64 (28.38±7.11) years, proportions of residence from Guangzhou, Guangdong province or other provinces as 38.6%(1 776/4 601)、35.4%(1 629/4 601) and 26.0%(1 197/4 601), 59.6%(2 742/4 601) received bachelor or above degrees. 81.3%(3 741/4 601) of them claimed as having homosexual orientation. R values of risk level on very low risk, low risk level, moderate risk, high risk and very high risk appeared as 12.9%(594/4 601), 50.9%(2 342/4 601), 17.0%(783/4 601), 14.8%(682/4 601) and 4.3%(200/4 601), respectively. Scores of modifiable risk factors decreased year by year (P<0.05), among MSM in this study. In either of the groups that experiencing insertive or receptive sex, the ones with heterosexual orientation presented the highest scores of modifiable risk factors (P<0.05). Conclusions: The risk levels on HIV infections called for special attention among the users of the self-evaluation network system. Among the MSM that carrying either insertive or receptive sex role, the ones with heterosexual orientation had the highest risk levels and scores of modifiable risk factors in Guangzhou. Further study should be explored to better understand the causes of related risks.

[Applicability and feasibility of "Lingnanzhun" -an "Internet Plus-based HIV Self-testing Tool" targeting MSM in Guangzhou].

Objective: This article was to evaluate the applicability and feasibility of "Lingnanzhun" -an "Internet Plus-based HIV Self-testing Tool" targeting MSM in Guangzhou. Hopefully, the results could be used to improve the existing HIV testing services and to support the implementation and scale-up of HIV self-testing programs. Methods: Data were collected from a survey on HIV testing preferences among the Internet-using MSM in April to June, 2015. Univariate and multivariate logistic regression analysis were applied to identify factors associated with the use of HIV self-testing service provided by Lingnanzhun. Information related to the users of Lingnanzhun during September 2014 and December 2018 was also collected. Results: 769 MSM were recruited as participants. Of them, age distribution was 16-77(28.6±6.8) years old, 88.3%(679/769) were unmarried, 42.2%(325/769) were registered residents of Guangzhou, 82.1%(631/769) had university or college education. Among them, 195 (25.4%) used the HIV self- testing program of Lingnanzhun while 574 (74.6%) using the clinic service. Compared with the clinic service users, the Lingnanzhun users showed the following characteristics: longer experience in the MSM community ≥10 years (32.8% vs. 20.9%, 64/195 vs. 120/574); having male casual sexual partners ≥2 (42.1% vs. 29.6%, 82/195 vs. 170/574); having group sex (6.2% vs. 2.6%, 12/195 vs. 15/574) and having commercial sex with men (13.8% vs. 3.0%, 27/195 vs. 17/574). Data from the Lingnanzhun users showed that a total of 3 000 users had practised 5 038 times of self HIV-testings. 11.4% (343/3 000) of the Lingnanzhun users had never been tested. Conclusions: It was applicable and feasible to provide Internet-based HIV self-testing service to MSM as a significant complement to the traditional facility-based HIV testing services. It was also useful in accessing those who were having higher risk or had never received HIV testing so as to increase the testing uptake and the frequency.

[Effectiveness of the "Internet Plus-based AIDS Comprehensive Prevention Service System" among MSM in Guangzhou].

Objective: To evaluate the effectiveness of the "Internet Plus-based AIDS Comprehensive Prevention Service System" among men who have sex with men in Guangzhou. Methods: Data through case-reporting and follow-up programs on MSM HIV/AIDS in Guangzhou was collected from the China Information System for Disease Control and Prevention, which including those from the referral and follow-up treatment compliance programs in 2008-2014 (pre-treatment) and 2017-2018 (post-treatment). According to the types of care services, three groups were set as: with "Internet Plus" service, with 'HIV counseling/testing service' or with 'routine medical service'. General Estimating Equation (GEE) was used to analyze the follow up situation of HIV/AIDS cases, annually. Cox proportional hazard regression model was used to analyze the proportions of treatment referral, within the 30 days of diagnosis. Results: Before the implementation of immediate treatment after HIV diagnosis, 90.6% (707/780) of the HIV/AIDS cases received the first follow up program including the CD(4)(+) T cells counts (CD(4)) test service within 90 days of diagnosis, in the "Internet Plus-based HIV/AIDS care service" group presented 1.19 times (95%CI: 1.14-1.25) of the routine medical service group. The implementation of immediate treatment after HIV diagnosis, compared with the routine medical service group, the "Internet Plus" service group presented 1.71 times (95%CI: 1.03- 2.83) more treatment referrals within the 30 days of diagnosis, when the first testing CD(4) was ≤200 cells/µl. Compared with the routine medical service group, the HIV counseling and testing service group showed 1.37 times (95%CI: 1.20-1.56) more of the treatment referrals within the 30 days of HIV diagnosis, after the first testing CD(4) counts as >200 cells/µl. Conclusion: Standardized care and follow-up service should be promoted as soon as the referral and treatment programs were set after the diagnosis was made, under the "Internet Plus-based AIDS Comprehensive Prevention Service System" for the MSM population, in Guangzhou.

[Clinicopathologic features of Cronkhite-Canada syndrome and the significance of IgG4-positive plasma cells infiltration].

Objective: To analyze the clinical and pathological features of Cronkhite-Canada syndrome (CCS), and to investigate the significance of IgG4 positive plasma cell infiltration. Methods: Clinical presentations, endoscopic appearances and morphological features of 18 patients diagnosed with CCS at Peking Union Medical College Hospital during 2000-2016 were included in the study.There were 11 male and 7 female patients. IgG4 and IgG immunohistochemical stains were performed in total of 55 biopsies from the patients (36 polyps, 10 adenoma and 9 surrounding mucosa) and a control group of 58 cases (19 colonic mucosa, 7 colonic hyperplastic polyps, 9 inflammatory bowel disease and 23 adenoma). Results: Average age of CCS was 59 years (range 47-69 years) and the male to female ratio was 11∶7. All patients had at least one ectoderm lesion. Fourteen cases had testicular abnormalities. Digestive tract symptoms were encountered in most cases. Four patients had a history of connective tissue disease. Endoscopically, multiple polyps were found to involve entire gastrointestinal tract except the esophagus. Morphologically, CCS polyps were characterized by prominent mucosal edema, mild to moderate inflammation, glands hyperplasia and cystic dilatation. Ten cases had colonic adenoma and one case had rectal adenocarcinoma. While none of the cases reached the diagnostic criteria of IgG4 disease, the positive rate of IgG4 positive plasma cells in adenoma of CCS was significantly higher than that in polyps and surrounding mucosa of CCS (60.0%∶13.9%∶0, P<0.01). The positive rate of IgG4 positive plasma cells of adenoma and polyp of CCS had an increased tendency compared to that of adenoma and polyp of control group (60.0%∶34.8%; 13.9%∶0). Conclusion: The findings in the study do not support that CCS is a variant of IgG4 disease, although IgG4 positive plasma cells may be involved in the pathogenesis of CCS, which may be explored in future investigations.