Prevalence of antiretroviral drug resistance in treatment-naive injecting drug users infected with HIV-1 in Guangzhou, 2008-2015 / 中华流行病学杂志

Objective: To understand the prevalence of drug resistance in treatment-naive injecting drug users (IDUs) infected with HIV-1 in Guangzhou. Methods: HIV-1 RNA were extracted from the serum specimens of the newly confirmed HIV-1 positive IDUs living in Guangzhou, being infected through injecting drug use and receiving no antiretroviral therapy at the time of confirmation during 2008-2015. Full sequence of pol protease (PR) gene and partial sequence of reverse transcriptase (RT) gene were amplified by nested reverse transcription polymerase chain reaction (nested-PCR) and sequenced. After that, data were submitted to the HIV resistance database of Stanford University for drug resistance analysis. Results: Among the 518 HIV-1 infected IDUs, HIV-1pol gene segments were successfully obtained from the serum samples of 407 HIV-1 infected IDUs (78.57%) aged 18-64 (37.44±8.14) years. Among them, males accounted for 89.68% (365/407), those of Han ethnic group accounted for 89.93% (366/407), the unmarried accounted for 55.28% (225/407), and those with education level of junior high school or below accounted for 83.78% (341/407). The distribution of subtypes was predominated by CRF07_BC (47.18%, 192/407), followed by CRF01_AE (23.83%, 97/407), CRF08_BC (22.85%, 93/407), and other subtypes (6.14%, 25/407). The overall prevalence of drug resistance was 3.44% (14/407). The prevalence of drug resistance to protease inhibitors, nucleoside reverse transcriptase inhibitors and non-nucleoside reverse transcriptase inhibitors were 1.47%(6/407), 0.25% (1/407) and 1.72% (7/407) respectively. The mutation rate was 12.29% (50/407). No major drug resistance mutation was detected in protease and nucleoside reverse transcriptase regions. Higher rate of V179E mutation in the non-nucleoside reverse transcriptase region was detected in other subtypes and subtype CRF07_BC. Mutation seemed to have occurred in all 8 cases of subtype CRF55_01B in other subtypes. The highest mutation rate of E138A was detected in subtype CRF08_BC (3.23%). Two cases were resistant to all four drugs of NNRTIs. Conclusions: The prevalence of drug resistance in treatment-naive HIV-1 positive IDUs remained at a relatively low level during 2008-2015, in Guangzhou. Most infections were sensitive to existing antiviral drugs. However, drug resistance surveillance in IDUs infected with HIV should be strengthened to prevent the prevalence of multi-drug resistance and cross drug resistance.

Characteristic and dynamic of HIV-1 subtype distribution in men who have sex with men in Guangzhou, 2008-2015 / 中华流行病学杂志

Objective: To understand the characteristics and dynamic of HIV-1 subtype distribution in men who have sex with men (MSM) in Guangzhou between 2008 and 2015. Methods: HIV-1 RNAs were extracted from serum samples of the individuals newly diagnosed with HIV-1 infection among MSM living in Guangzhou between 2008 and 2015. The pol gene segments of HIV-1 genome from these RNA samples were amplified by nested reverse transcription polymerase chain reaction (nested-PCR) and were sequenced. Subsequently, the phylogenetic tree was reconstructed using pol sequences of samples and references together and the subtype of HIV-1 was determined. The distributions of HIV-1 subtypes detected in MSM with different demographic characteristics in different years were compared. Results: A total of 2 210 pol gene segments were successfully obtained from 2 473 serum samples of the MSM. The average age of 2 210 MSM was 30.19 years with standard deviation of 8.22 years, the unmarried MSM and those in Han ethnic group accounted for 73.39% and 90.81%, respectively. The proportion of subtype CRF07_BC (38.10%) was highest, followed by CRF01_AE (34.84%), CRF55_01B (14.62%), B (6.06%), URFs (3.58%), CRF59_01B (2.17%) and other subtypes (0.63%). The annual proportions of subtype B (P=0.000, 99%CI:0.000-0.000), CRF07_BC (χ(2)=14.965, P=0.036), CRF55_01B (χ(2)=18.161, P=0.011) and URFs (P=0.001, 99% CI: 0.000-0.001) were significantly different. The proportion of subtype B showed a gradual decrease from 14.08% to 4.33% (P=0.000, 99%CI: 0.000-0.000), while the proportion of URFs rapidly increased from 0% to 6.40% (P=0.000, 99% CI: 0.000-0.000). The rate of URFs was significantly higher in farmers and migrant workers than in other groups (P=0.017, 99%CI: 0.014- 0.020) and the rate of URFs was higher in individuals who had multi sexual partners (χ(2)=5.733, P=0.017). Conclusions: CRF07_BC and CRF01_AE were the predominant HIV-1 subtypes and multiple subtypes co-circulated among MSM in Guangzhou between 2008 and 2015. The recombinations of HIV-1 continue to occur in MSM. Strengthening behavioral intervention for farmers, migrant workers and individuals who have multi sexual partners has the important epidemiological significance against the emerging and circulating of the novel recombinant virus among MSM in Guangzhou.

Associations of obesity and physical activity with cognition in people aged 50 and above in Shanghai / 中华流行病学杂志

Objective: To investigate the associations of obesity and physical activity with cognition in the elderly. Methods: A cross-sectional survey was conducted from October 2009 to June 2010 among people aged ≥50 years selected through multistage random cluster sampling in Shanghai. The subjects' body weight, body height, waist circumference and hip circumference were measured to calculate body mass index (BMI) and waist-hip ratio (WHR), and the data on self-reported physical activity level were collected through questionnaire survey. A comprehensive battery of cognitive tests was conducted to assess subjects' cognitive functions, including verbal recall, forward digit span (FDS), backward digit span (BDS), and verbal fluency (VF). General linear model was used to examine the associations of BMI, WHR and physical activity with cognition. Results: A total of 7 913 participants were included, with a median age of 60 years. Age, sex, education level, income level, BMI, WHR and physical activity level were significantly associated with cognitive scores in univariate analysis. After adjusted for age, sex, education level and income level, BMI was no longer significantly associated with cognitive scores in all cognitive functions (all P>0.01). WHR was significantly associated with VF score (P<0.01). Abdominally obese participants had lower VF score than non-abdominally obese participants (P<0.01). Physical activity level was significantly associated with all cognitive functions (P<0.01). Compared with participants with moderate physical activity level, participants with low physical activity level had lower scores in all cognitive functions (P<0.01). Conclusion: Abdominal obesity and low physical activity level were negatively associated with cognition level in the elderly, suggesting that waist circumference control and physical activity might help maintain cognition in the elderly.

Characteristics and influencing factors regarding social relations among men who have sex with men / 中华流行病学杂志

Objective: To study the characteristics of social relations and relative factors among MSM in Guangzhou. Methods: Data was collected through a cross-sectional study in Guangzhou from November 2016 to May 2017. Sample size was estimated and participants were recruited from the voluntary counseling and testing services (VCT) which were set for MSM population, by nongovernmental organizations (NGOs) and the Centers for Disease Control and Prevention (CDC). Social ties and demographic characteristics of the respondents and their sexual partners were analyzed through both Chi square test and generalized estimating equations (GEE). Results: A total of 1 073 MSM, together with their nominated 4 301 partners were successfully recruited and involved in this study. Age (OR=1.2, P=0.01) and non-internet based intercourse (OR=1.65, P<0.01) were easy to form close relation with strong ties. Compared with MSM traditional venues (chess and cards room, tea room bathhouse, club), general public venue (bars, KTV, parks, shopping malls, schools, restaurants) (OR=1.46-3.12, P<0.01) showed close relation with strong ties. Our finding showed that MSM at the age of 18-25 preferred to build weak ties with the older MSM, while the 26-30-year-olds and 31-40-year-olds prefer to establish weak ties with younger partners but the 41-50-year-olds preferred to develop weak ties with one that were ten years younger. Conclusions: Clusters were noticed in the MSM populations when grouping and making friends with ones at different age. Characteristics regarding the relationship between sexual partners in choosing venues and ways of dating were different. Targeted intervention programs need to be explored innovatively.

Analysis on reproductive health service, demographics and characteristics of internal migrant population in three municipalities of China / 中华流行病学杂志

Objective: To investigate the utilization of reproductive health services and relating factors among internal migrant population in Beijing, Shanghai and Chongqing. Methods: A multi-stage cluster sampling method was adopted in this cross-sectional study, conducted in Beijing, Shanghai and Chongqing from August 2014 to August 2015. Standard methods on statistics and nonlinear canonical correlation were applied. Results: Out of the 6 545 internal migrant persons, 41.76% ever used the reproductive health services in the past year. Results from the nonlinear canonical correlation analysis revealed that the utilization of reproductive health services was correlated with the demographic features (=0.28, P<0.000 1) and characteristics of the population mobility (=0.21, P<0.000 1), respectively. For the above said demographic features, canonical variable L(1) which represented the demographic features was mainly determined by area, occupation and education attainment. Canonical variable M(1) that reflected the utilization of reproductive health services, was mainly determined by factors as free contraceptives, education on contraception/reproductive health, and pregnancy diagnosis/antenatal care. As for the characteristics of the population mobility, canonical variable U(1), which represented population mobility characteristics, was mainly determined by factors as purpose of migration, current pattern of residence and the length of annual stay in the area. Again, the canonical variable V(1), reflecting the use of reproductive health services was mainly determined by factors as free contraceptives, check-up on reproductive tract infection, education on contraception/reproductive health, and pregnancy diagnosis/antenatal care. Conclusions: The utilization of reproductive health services was low among the internal migrant population under study. Responsible departments for health and family planning in those cities should make internal migrants attach importance to reproductive health.

Fewer beams and segments result in a shorter delivery time and a better quality intensity-modulated radiotherapy plan in gastric cancer

Background: This study evaluated whether IMRT using fewer beams and segments could reduce delivery time without compromising plan quality in gastric cancer adjuvant radiotherapy

Materials and Methods: Fifteen patients with advanced gastric cancer who underwent D2, R0 surgery were included in this study. IMRT plans for each patient were designed as 7 equal beams with 40 segments, 5 beams with 25 segments and 4 beams with 20 segments. The dosimetric parameters were compared for the planned target volume [PTV]. The dose of normal organs at risk [OARs] was also assessed. The monitor units and treatment times of the different IMRT plans were calculated

Results: The 20-segment IMRT plan significantly reduced the PTV maximum dose compared to the 40-segment IMRT plan. The 20-segment IMRT plan improved left kidney and liver dose sparing in V20 and V30 as well as the 40-segment IMRT plan did and provided be4er protection for the V20 [13.86+/-7.78] of the right kidney, the V30 [9.25+/-4.04] of the le kidney, the D mean [19.68+/-2.47] of liver and D max [38.79+/-3.57] of the spinal cord. Irradiation times in the 20-segment and 25-segment plans decreased by 2.5 and 1.9 min, respectively, compared to the 40-segment IMRT plan

Conclusion: IMRT using fewer beams and segments reduced delivery time without compromising plan quality in gastric cancer adjuvant radiotherapy. Fewer segments IMRT plans lowered the monitor units and the treatment time

Comparison of different indicators of iodine deficiency in school children

To compare different indicators of iodine deficiency disorders [IDD] in school children from study sites in Bangladesh Indonesia, Guatemala, and the United States. Cross-sectional surveys were performed in Savar, Bangladesh; Sukabumi, Indonesia; San Pedro Sacatepequez, Guatemala; and Atlanta, United States. In each study site, school children were assessed for thyroid size by palpation and thyroid volume by ultrasonography, urine specimens collected for iodine concentration, and finger stick blood specimens spotted onto filter paper for assessment of thyroid stimulating hormone [TSH] and thyroglobulin [Tg]. Weights and heights were collected in all sites except Guatemala. Between 305 to 518 school children were surveyed in each site. Indicators based on thyroid size tended to indicate more severe levels of iodine deficiency compared to urinary iodine based on WHO/UNICEF/ICCIDD criteria. TSH levels appeared to correlate well with other indicators of IDD whereas Tg did not. In these study sties, it appeared that urinary iodine, thyroid volume [based on body surface area], palpation, and TSH were consistent in identifying the Bangladesh site as having the highest prevalence of IDD, followed by sites in Indonesia, Guatemala, and the United States. The prevalence of goiter indicated more severe levels of IDD compared to urinary iodine levels. Tg was not significantly different between the study sites