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BACKGROUND: Although effects of weather changes on human health have been widely reported, there is limited information regarding effects on pregnant women in developing countries. OBJECTIVE: We investigated the association between maternal exposure to ambient temperature and the risk of preterm birth (< 37 weeks of gestation) in Guangzhou, China. METHODS: We used a Cox proportional hazards model to estimate associations between preterm birth and average temperature during each week of gestation, with weekly temperature modeled as a time-varying exposure during four time windows: 1 week (the last week of the pregnancy), 4 weeks (the last 4 weeks of the pregnancy), late pregnancy (gestational week 20 onward), and the entire pregnancy. Information on singleton vaginal birth between 2001 and 2011 was collected. Daily meteorological data during the same period were obtained from the Guangzhou Meteorological Bureau. RESULTS: A total of 838,146 singleton vaginal births were included, among which 47,209 (5.6%) were preterm births. High mean temperatures during the 4 weeks, late pregnancy, and the entire pregnancy time windows were associated with an increased risk of preterm birth. Compared with the median temperature (24.4°C), weekly exposures during the last 4 weeks of the pregnancy to extreme cold (7.6°C, the 1st percentile) and extreme heat (31.9°C, the 99th percentile) were associated with 17.9% (95% CI: 10.2, 26.2%) and 10.0% (95% CI: 2.9, 17.6%) increased risks of preterm birth, respectively. The association between extreme heat and preterm birth was stronger for preterm births during weeks 20-31 and 32-34 than those during weeks 35-36. CONCLUSIONS: These findings might have important implications in preventing preterm birth in Guangzhou as well as other areas with similar weather conditions. http://dx.doi.org/10.1289/ehp.1509778, Introduction Preterm birth, defined as birth < 37 completed weeks of gestation, is a complex syndrome and remains a major global public health problem (Goldenberg et al. 2008; Muglia and [...]

Objective: To investigate the expression rules of FOXO1a, FOXO3a, FOXO4 and FOXO6 proteins in the human testis, and explore their roles in the development and progression of testicular aging., Methods: We collected the para-carcinoma testis tissue from 4 testis cancer patients aged 28, 31, 32 and 46 years, and the testis tissue from another 2 PCa patients aged 66 and 81 years after castration surgery from January 2018 to December 2020. We detected the expressions of FOXO1a, FOXO3a, FOXO4 and FOXO6 proteins in the testis tissue by Western blot, determined the locations of FOXO1a, FOXO3a, FOXO4 and FOXO6 in the testis cells by immunofluorescence staining, and performed semi-quantitative and statistical analyses using image J and SPSS 23.0 software, respectively., Results: The expression levels of FOXO1a and FOXO3a proteins were significantly decreased in the testis tissue of the elderly patients (P < 0.01), with an age-dependent reduction in the proportion of the positive cells. No statistically significant difference was observed in the expression levels of FOXO4 and FOXO6 between different age groups. FOXO1a was mainly expressed at the base of the seminiferous tubules, FOXO3a and FOXO4 in the Leydig cells, and FOXO6 in the seminiferous tubules. In addition, FOXO4 underwent age-related nuclear translocation in the senescent Leydig cells, suggesting its involvement in the aging of Leydig cells., Conclusion: FOXO1a/3a/4 may be closely related to human testicular aging and corresponding pathological changes, but its underlying mechanism remains to be further explored.

Objective: To explore the appropriate ways and contents of reproductive health education for middle school students and to understand reproductive health related sexual behavior and influencing factors among middle school students., Methods: Reproductive health related sexual behavior was evaluated among junior and senior middle school students in Luoyang by cluster sampling. The statistical software of SAS 8.1 was adopted for data analyses. Sexual behavior and influencing factors were analyzed by logistic regression., Results: Critical sexual behaviors were found significantly higher in senior students, including masturbation, sexual fantasy and sexual intercourse than that in junior students (P < 0.05), and boys had higher prevalence than girls (P < 0.05). Results from multivariate logistic regression model analyses indicated that incidence rate of sexual behavior among those who ever having had experiences was higher than those who were inexperienced (OR = 2.62, 95%CI: 1.21 - 5.66). Incidence rate of sexual behavior was related to access of reproductive health and STD/AIDS knowledge (OR = 3.09, 95%CI: 1.43 - 6.51). In addition, incidence rate of sexual behavior was related to attitude and relation of amour between boys and girls (OR = 2.24, 95%CI: 1.32 - 3.75)., Conclusion: Awareness on reproductive health knowledge among middle school students was not enough. Marginal sexual behaviors as masturbation and sexual fantasy had not been correctly and openly discussed to avoid inappropriate sexual activities.

To develop and validate an ultra performance liquid chromatography tandem mass spectrometric (UPLC-MS/MS) method for the simultaneous quantification of baicalin and chlorogenic acid in human plasma after iv infusion of Yinhuang injection, the analytes were isolated from plasma by protein precipitation with methanol. Then they were chromatographied on an Acquity UPLC BEH C18 column (50 mm x 2.1 mm ID, 1.7 microm) at 40 degrees C. The mobile phase A consisted of water and 0.1% formic acid. The mobile phase B consisted of methanol and 0.1% formic acid. The analytes were eluted from the column with a linear gradient from 5% B to 80% B in 5 min, then hold for 0.5 min before returning to initial condition. The flow rate was 0.35 mL x min(-1). A tandem mass spectrometer equipped with electrospray ionization source was used as detector. Multiple reaction monitoring (MRM) using the precursor to product ion pairs of m/z 447-->271 (for baicalin), m/z 353-->191 (for chlorogenic acid) and m/z 287-->287 (for internal standard) were used to quantification. The linear concentration ranges of the calibration curves for baicalin and chlorogenic acid ranged from 9.6 to 1540 ng x mL(-1) and from 7.5 to 1200 ng x mL(-1), respectively. The intra- and inter-day relative standard deviation (RSD) across three validations run over the entire concentration range was less than 10.2% for both baicalin and chlorogenic acid. After iv infusion of Yinhuang injection to the volunteers, the concentration-time curves of baicalin and chlorogenic acid fitted the two-compartment and three-compartment model. T(1/2)alpha were (4.47 +/- 0.89) and (7.65 +/- 4.42) min, T(1/2)beta were (46.22 +/- 10.03) and (34.40 +/- 19.16) min, respectively. The method was proved to be highly sensitive, selective, and suitable for pharmacokinetic investigations of both baicalin and chlorogenic acid.

Background: Studies showed that propentofylline enhances the action of adenosine and protects hippocampal neuronal damage against transient global cerebral ischaemia. Our study was to investigate the effect of propentofylline on hypoxic-ischaemic brain damage in neonatal rat., Methods: Seven-day-old Wistar rats were subjected to unilateral common carotid artery ligation and hypoxia in oxygen 8 kPa for two hours at 37 degrees C. Propentofylline (10 mg/kg) was administered intraperitoneally one hour after hypoxia-ischaemia (treated group). Control group rats were received an equivalent volume of saline. The effects of propentofylline were assessed by observing the body mass gain, behavioural alteration and neurohistological changes. The rats were sacrificed at 72 hours after hypoxia-ischaemia, and the brain sections were examined after haematoxylin and eosin staining., Results: The propentofylline-treated rats had better body mass gain and better behavioural response than the paired saline-controls did. In the control group, the rats either lost body mass or had little mass gain after the insult, their average body mass gain was 97.3% at 24 h, 100.3% at 48 h, and 114.1% at 72 h of recovery. In propentofylline-treated group, there was a significant improvement of body mass gain at 24 h (100.2%, P < 0.05) and 48 h (110.3%, P < 0.01) of recovery; the percentage of rats that performed well on behavioural test was significantly higher from 48 h to 72 h of recovery (P < 0.05); the incidence of severe brain damage to the cerebral cortex and dentate gyrus was significantly reduced in propentofylline-treated rats (cortex, 93% - 70.8%, P < 0.01; dentate gyrus 95% - 66.7%, P < 0.01) as compared with control rats., Conclusions: Administration of propentofylline 1 hour after hypoxia-ischaemia significantly attenuates brain damage in both the cerebral cortex and dentate gyrus, and also improves the body mass gain as well as behavioural disturbance in 7-day-old rats.