Effects of education level of men who have sex with men on their high risk sexual behaviors and the infection of HIV and syphilis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the effects of educational background of men who have sex with men (MSM) on their high risk sexual behaviors and the HIV/STI infection rates.</p><p><b>METHODS</b>During July to November of 2009 and March to October of 2010, snowball and convenience sampling methods were adopted to recruit MSM from MSM venues and via the internet in Changzhou city of Jiangsu province, and finally 659 MSM were conducted a questionnaire survey and serological testing. According to the educational background of MSM, they were divided into 3 groups, that is, junior high school group (206 cases), high school group (254 cases), and university group (199 cases). The questionnaire mainly includes information on social demography, sexual behaviors, condom use, etc. Blood samples were collected for HIV and syphilis spirochete detection, and urine samples were also collected in 291 MSM who were recruited during July to November of 2009 for neisseria gonorrhoeae and chlamydia trachomatis nucleic acid detection. χ(2) test and other statistical analysis methods were used to compare the characteristics of sexual behaviors and HIV/STI infections in 3 groups.</p><p><b>RESULTS</b>Of the 659 valid questionnaires returned, junior high school group, high school group, and university group accounted for 31.3% (206 cases), 38.5% (254 cases) and 30.2% (199 cases). Places where MSM of different education levels most often to seek sexual partners, were significantly different. Junior high school group and high school group mostly went to bath house/sauna club (56.3%, 116 cases) and bar (34.8%, 88 cases) for partners, respectively, while the university group sought partners mainly through the internet (41.1%, 81 cases) (χ(2) = 99.35, P < 0.05). 53.4% (109/204) of the junior high school group had anal sex with men in the last 6 months, which was higher than that of high school group (67.7%, 172/254) (χ(2) = 9.74, P < 0.05) and university group (72.7%, 144/198) (χ(2) = 16.04, P < 0.05) . A total of 54.4% (111/204) of the junior high school group had sex with women in the last 6 months, which was higher than that of university group (38.6%, 76/197) (χ(2) = 10.10, P < 0.05) , but was not statistically significantly different from that of high school group (46.9%, 119/254) (χ(2) = 2.59, P = 0.11) . The rates of condom use with men at the last anal sex in junior high school group (73.4%, 80/109) , high school group (78.0%, 131/168) and university group (73.9%, 105/142) were similar. The rates of condom use with women in the last intercourse in junior high school group, high school group and university group were 51.8% (57/110), 54.6% (65/119) and 61.8% (47/76), respectively(χ(2) = 1.88, P = 0.39) . In junior high school group, high school group and university group, the infection rates of HIV were 9.2% (19/206), 10.6% (27/254) and 5.6% (11/197) (χ(2) = 3.68, P = 0.16), the positive rates of neisseria gonorrhoeae were 3.8% (3/79), 3.4% (4/117) and 0.0% (0/95) (χ(2) = 3.85, P = 0.14), the positive rates of chlamydia trachomatis were 5.1% (4/79), 9.4% (11/117) and 4.2% (4/95) (χ(2) = 2.70, P = 0.26). The infection rate of syphilis in junior high school group was 19.9% (41/206), which was higher than high school group (12.2%, 31/254) (χ(2) = 5.11, P < 0.05) and university group (10.2%, 20/197) (χ(2) = 7.45, P < 0.05 ).</p><p><b>CONCLUSION</b>There was no obvious correlation between education level and high risk sexual behaviors;MSM with lower education level were at higher risk of infection of syphilis.</p>

Comparative analysis on both high risk behaviours, infection of HIV and syphilis between married and unmarried men who have sex with men / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the distribution of marriage status among men who have sex with men (MSM) in the city of Changzhou, and to explore the impact of marriage on AIDS related high risk behaviors and HIV infection in this population.</p><p><b>METHODS</b>Target sampling (snowball sampling) was adopted to carry out a cross-sectional study, and structured questionnaire-based interviews were conducted to collect information on social demography, HIV related high risk behaviors. Blood and urine samples were collected to detect HIV, syphilis, gonorrhea and Chlamydia trachomatis infections.</p><p><b>RESULTS</b>Of the 655 participants, 37.4% were married. Married MSM mostly sought their sexual partners at the public bathing house (61.6%), while unmarried MSM were mainly through bars (33.6%) or internet (31.1%). The proportion of having anal sex with men during the last 6 months was lower in the married group (50.8%) than in the unmarried group (73.3%), (P < 0.001) The percentage of having sex with women in the last 6 months was significantly higher in the married group (68.9%) than that in the unmarried group (33.2%) (P < 0.001), (OR = 4.454, 95%CI: 3.168 - 6.261). The rates of condom use in the last anal sex with men in married and unmarried groups were 71.0% and 77.6%, respectively (P = 0.152). The rate of condom use in the last intercourse with women was significantly lower in the married group (44.0%) than that in the unmarried group (70.4%) (P < 0.001), (OR = 0.331, 95%CI: 0.205 - 0.535). In the sex trade, most of the married MSM would "buy" sex (66.7%), while unmarried MSM would "sell" sex (63.2%) (P < 0.05), (OR = 3.429, 95%CI: 1.255 - 9.366). The percentage of having drugs in the previous year was higher in married group (3.3%) than that in the unmarried group (0.8%) (P < 0.05). In married and unmarried groups, the infection rates of HIV, syphilis, gonorrhea and Chlamydia trachomatis appeared to be (8.6%, 8.6%), (17.1%, 12.3%), (1.6%, 2.4%), and (3.3%, 9.0%), respectively (P > 0.05).</p><p><b>CONCLUSION</b>Marriage seemed to have had limited effects on reducing the high risk behaviors of MSM. Different and multiform interventions should be developed according to the different characteristics of married or unmarried MSM population.</p>

The effect of inhalable titanium dioxide on the oxidative stress among occupational population / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the inhalable titanium dioxide exposure level and make an assessment of its oxidative effect on occupational exposed population.</p><p><b>METHODS</b>A total of 7 workers occupationally exposing to inhalable titanium dioxide were recruited into the study. The basic information and occupational history were collected by interview, while their blood sample (10 ml for each subject) were collected before and after the investigation, respectively. Pre- and post-work shift urine samples (60 ml for each subject) were collected for 29 days consecutively. The daily personal titanium dioxide exposure level, temperature and relative humidity were detected too. Urinary 8-hydroxy-deoxyguanosine (8-OHdG) and serum high-sensitivity C-reactive protein (hs-CRP) were detected by ELISA and latex immunoturbidimetric assay, respectively.</p><p><b>RESULTS</b>The mean concentration of air inhalable titanium dioxide was (1.194 ± 1.015) mg/m(3). Serum hs-CRP level before and after the investigation was (1.13 ± 1.08), (1.33 ± 1.01) mg/L, respectively. No statistical significance was observed between hs-CRP level before and after the investigation (t = -0.848, P = 0.425). Pre- and post-work shift urinary 8-OHdG was (3.51 ± 1.39), (3.65 ± 1.06) µmol/mol Cr, respectively. A positive correlation was found between the concentration of inhalable titanium dioxide and the changes of 8-OHdG level (r = 0.192, t = 2.09, P = 0.039). Linear mixed-effect models, adjusted by work shift, years of employment, age, body mass index, smoking status, temperature and relative humidity, showed no significant exposure-respond trend between the inhalable titanium dioxide concentration and 8-OHdG level (β = 0.288, t = 1.940, P = 0.055).</p><p><b>CONCLUSION</b>Our findings do not support the potential link between occupationally exposure to inhalable titanium dioxide and high induction of DNA oxidative stress.</p>

Effect of nano-TiO(2) intratracheal instillation on lipid metabolism of AopE gene-knockout mice / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of nano-TiO(2) intratracheal instillation on the progression of dyslipidemia and atherosclerosis in apolipoprotein E-knockout mice.</p><p><b>METHODS</b>The nano-TiO(2) was ultrasound with phosphate-buffered saline solutions (PBS) into its suspension for exposure. A total of 46 specific pathogen free (SPF) level of 11-week-old male apolipoprotein E-knockout mice were randomly divided into groups by their body weights: non-treatment group (8 mice), PBS control group (9 mice), high dose group (1.0 mg/ml, 10 mice), medium dose group (0.5 mg/ml, 10 mice), and low dose group (0.1 mg/ml, 9 mice). Except the non-treatment group, mice from other groups were intratracheally instilled with 0.05 ml each time, twice a week. After exposure of 6 weeks, viscera index, blood TC, TG, HDL-C, LDL-C, and organic lipid ratio were assessed as biomarkers. Artery and aortic root issues were assessed by histopathology.</p><p><b>RESULTS</b>After 5 weeks exposure, mice body weights in high dose group ((29.7 ± 1.9) g) started to drop, compared to PBS control ((31.3 ± 1.9) g, t = -1.58, P < 0.05) and low dose group ((31.4 ± 1.4) g, t = -1.17, P < 0.05); after 6 weeks, high dose group ((28.8 ± 1.5) g) was lower than PBS control ((30.4 ± 1.9) g, t = -1.60, P < 0.05), non-treatment group ((30.2 ± 1.3) g, t = -1.43, P < 0.05) and low dose group ((30.6 ± 1.0) g, t = -1.83, P < 0.05). TC levels of non-treatment, PBS control, high dose group, medium dose group and low dose group were (2.92 ± 1.18), (3.12 ± 0.73), (4.19 ± 1.86), (3.46 ± 0.72) and (2.57 ± 0.64) mmol/L, respectively; TG levels were (0.39 ± 0.13), (0.39 ± 0.08), (0.60 ± 0.21), (0.55 ± 0.19) and (0.41 ± 0.11) mmol/L, respectively; HDL-C levels were (1.67 ± 0.45), (1.54 ± 0.67), (0.93 ± 0.50), (1.02 ± 0.48) and (1.31 ± 0.64) mmol/L; TG levels of high dose group were higher than that of non-treatment group (t = 1.27, P = 0.03) and low dose group (t = 1.62, P = 0.01); TG levels of medium dose group was higher than PBS control (t = 0.16, P = 0.04), and TC levels of high dose group were higher than PBS control (t = 0.22, P = 0.01), non-treatment group (t = 0.22, P = 0.04) and low dose group (t = 0.20, P = 0.03), and HDL-C levels of high dose group were lower than PBS control (t = -0.61, P = 0.04) and non-treatment group (t = -0.74, P = 0.04); organic lipid ratio of each group were (2.27 ± 0.51)%, (2.06 ± 0.53)%, (2.90 ± 0.50)%, (2.60 ± 0.23)%, (2.24 ± 0.45)%; high dose group were higher than PBS control (t = 0.85, P = 0.00), non-treatment group (t = 0.64, P = 0.03) and low dose group (t = 0.67, P = 0.01); medium dose group was higher than PBS control (t = 0.54, P = 0.02). The plaque lipid content and calcium content which showed the progression of atherosclerosis and plaque rupture were elevated in medium and high dose groups.</p><p><b>CONCLUSION</b>Intratracheal instillation of nano-TiO(2) can induce dyslipidemia and accelerate the development of atherosclerosis and plaque rupture in ApoE-/-mice.</p>