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Emerging evidence from observational studies proves the association between preterm birth (PTB) and phthalate metabolites; however, such findings are inconsistent and inconclusive. This meta-analysis aimed to clarify this association by accessing the connection between 11 phthalate metabolites and PTB, and 6 phthalate metabolites and spontaneous PTB. The PubMed, Embase, and WOS (Web of Science) databases were searched up to July 2020. Seven prospective studies met the inclusion criteria. Pooled odds ratios (OR) with 95 % confidence intervals (CIs) were calculated for risk estimation. Our results indicated that mono-n-butyl phthalate (MBP), sum of di-2-ethylhexyl phthalate (ΣDEHP), and mono 3-carboxypropyl phthalate (MCPP) significantly correlated with the risk of PTB (MBP: OR = 1.23, 95 % CI = 1.05-1.45; ΣDEHP: OR = 1.21, 95 % CI =1.01-1.44; MCPP: OR = 1.09, 95 % CI = 1.00-1.19). Pooled results showed that spontaneous PTB was associated with higher urinary levels of mono-ethyl phthalate (MEP), MCPP, mono-isobutyl phthalate (MIBP), and MBP (MBP: OR = 1.27, 95 % CI = 1.02-1.58; MEP: OR = 1.19, 95 % CI = 1.01-1.40; MCPP: OR = 1.15, 95 % CI = 1.02-1.30; MIBP: OR = 1.38, 95 % CI = 1.12-1.71). Overall, we conclude that during pregnancy, MBP, ΣDEHP, and MCPP levels are associated positively with PTB. MBP, MEP, MCPP, and MIBP levels had increased odds of spontaneous PTB. No significant associations were observed between other phthalate metabolites and PTB or spontaneous PTB. Further research is needed to verify these findings and elucidate the association of phthalate levels and PTB.

The study aimed to examine the associations between the level of trihalomethanes and its metabolites in pregnancy and the risks of adverse birth outcomes. We searched the databases of the China National Knowledge Infrastructure, WanFang, Vip, PubMed, and Elsevier Science Direct from database establishment to July 14, 2021 and performed a systematic review and meta-analysis of observational studies reporting associations between trihalomethanes level and abnormally low birth weight and preterm birth. The pooled odds ratio (OR), pooled risk ratio, and pooled risk difference with their 95% confidence interval (CI) were calculated for risk estimates. A total of 24 studies involving 1,118,037 pregnant women were finally enrolled in the present systematic review and meta-analysis. Our research found that abnormally low birth weight was associated with higher levels of total trihalomethanes (OR = 2.45, 95% CI: 1.28, 4.68; P = 0.007). Unexpectedly, the meta-analysis indicated that higher total trihalomethanes level was associated with lower odds of preterm birth (OR = 0.90, 95% CI: 0.81, 0.99; P = 0.03). Our findings indicate that trihalomethanes exposure might be a risk factor for abnormally low birth weight and that it would be prudent to minimize exposure to trihalomethanes during pregnancy because of the risk of abnormally low birth weight. Given some limitations of the systematic review and meta-analysis, our results should be interpreted with caution.

Background Epidemiological studies on the associations of legacy per- and polyfluoroalkyl substances (PFASs) and glucose homeostasis remain discordant. Understanding of PFAS alternatives is limited, and few studies have reported joint associations of PFASs and PFAS alternatives. Objectives To investigate associations of novel PFAS alternatives (chlorinated perfluoroalkyl ether sulfonic acids, Cl-PFESAs and perfluorobutanoic acid, PFBA) and two legacy PFASs (Perfluorooctanoic acid, PFOA and perfluorooctane sulfonate, PFOS) with glucose-homeostasis markers and explore joint associations of 13 legacy and alternative PFASs with the selected outcomes. Methods We used cross-sectional data of 1,038 adults from the Isomers of C8 Health Project in China. Associations of PFASs and PFAS alternatives with glucose-homeostasis were explored in single-pollutant models using generalized linear models with natural cubic splines for PFASs. Bayesian Kernel Machine Regression (BKMR) models were applied to assess joint associations of exposures and outcomes. Sex-specific analyses were also conducted to evaluate effect modification. Results After adjusting for confounders, both legacy (PFOA, PFOS) and alternative (Cl-PFESAs and PFBA) PFASs were positively associated with glucose-homeostasis markers in single-pollutant models. For example, in the total study population, estimated changes with 95% confidence intervals (CI) of fasting glucose at the 95th percentile of 6:2Cl-PFESA and PFOS against the thresholds were 0.90 (95% CI: 0.59, 1.21) and 0.44 (95% CI: 0.26, 0.62). Positive joint associations were found in BKMR models with 6:2Cl-PFESA contributing most. Sex-specific associations existed in both single- and multi-pollutant models. Conclusions Legacy and alternative PFASs were positively associated with glucose-homeostasis markers. 6:2Cl-PFESA was the primary contributor. Sex-specific associations were also identified. These results indicate that joint associations and effect modification should be considered in risk assessment. However, further studies are recommended to strengthen our findings and to elucidate the mechanisms of action of legacy and alternative PFASs.

Background: Malnutrition and tuberculosis (TB) tend to interact with each other. TB may lead to nutrition deficiencies that will conversely delay recovery by depressing immune functions. Nutrition support can promote recovery in the subject being treated for TB. The aim of this study was to evaluate the effectiveness of nutrition support on promoting the recovery of adult pulmonary TB patients with anti-TB drug therapy. Methods: English database of the Cochrane Controlled Trials Register, PubMed, EMBASE, and Chinese database of CBM, CNKI, VIP, and WANFANG were searched. Randomized controlled trials comparing nutrition support (given for more than 2 weeks) with no nutrition intervention, nutrition advice only, or placebo-control for TB patients being anti-TB treated were included. Two reviewers conducted data extraction, assessed the quality of the studies independently, and any discrepancies were solved by the third reviewer. Data were entered and analyzed by RevMan 5.2 software, and meta-analysis was done using risk ratios ( RR s) for dichotomous variables and mean differences (MDs) for continuous variables with 95% confidence intervals ( CI s). Results: A total of 19 studies (3681 participants) were included. In nutritional support for TB patients, pooled RR and its 95% CI of sputum smears- or culture-negative conversion rate and chest X-ray (CXR) absorption rate were 1.10 (1.04, 1.17) and 1.22 (1.08, 1.39), respectively, the pooled MD and its 95% CI of body mass index (BMI) and time of sputum smears or culture negativity were 0.59 (0.16, 1.2) and − 5.42 (−7.93, −2.92), respectively, compared with the control group. The differences in outcomes of CXR zone affected, TB score, serum albumin, and hemoglobin were not statistically significant ( P = 0.76, 0.24, 0.28, and 0.20, respectively) between the intervention group and the control group. No systemic adverse events were recorded. Conclusions: During anti-TB course, nutrition support may be helpful in treatment of TB patients by improving both sputum smears- or culture-negative conversion rate and BMI, shortening the time of sputum conversion negative. Whether it can improve the final clinical effect, there still needs high-level quality studies to confirm in the future.

To investigate the relationship of the levels of serum androgens with lipid metabolism in middle-aged and elderly men in Zunyi, Guizhou.Using the stratified cluster sampling method, we conducted a questionnaire investigation and physical examinations among 437 men in Zunyi City. We divided the subjects into a middle-aged (40－64 ［53.20 ± 7.41］ years, n = 269) and an elderly group (=≥65 ［70.63 ± 4.66］ years, n = 168) and collected fasting elbow venous blood samples from them for measuring the levels of total testosterone (TT), sex hormone-binding globulin (SHBG), luteinizing hormone (LH), total cholesterol (TCH), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), calculated free testosterone (cFT), free testosterone index (FTI), and testosterone secretion index (TSI).Compared with the elderly group, the middle-aged males showed significantly lower SHBG, LH, HDL and LDL, and higher cFT, FTI, TSI, TG and TCH (all P0.05). TT and SHBG were negatively correlated with TG, TCH, HDL and LDL, while cFT was positively correlated with TCH, and so was FTI with TG, TCH with LDL, and TSI with TCH, HDL and LDL (all P0.05), but LH was negatively correlated with TG, TCH and LDL (all P0.05). Multivariate linear regression analysis showed that TT and SHBG were negatively correlated with TG, TCH, HDL and LDL, and so was LH with TCH, HDL and LDL (all P0.05).In the middle-aged and elderly men in Zunyi, low concentrations of TT, SHBG and LH were associated with the increased risk of high-TCH and -LDL dyslipidemia, low concentrations of TT and SHBG with that of high-TG dyslipidemia, while high concentrations of TT, SHBG and LH with that of low-HDL dyslipidemia.目的： 探究贵州遵义市中老年男性血清雄激素水平与血脂代谢的关系。方法： 采用分层整群抽样方法在遵义市抽取437例年龄=≥40岁的男性行问卷调查和体格检查，采集空腹肘静脉血样标本检测血清总睾酮（TT）、性激素结合球蛋白（SHBG）、黄体生成素（LH）、总胆固醇（TCH）、甘油三脂（TG）、高密度脂蛋白（HDL）和低密度脂蛋白（LDL），计算游离睾酮（FT）、游离睾酮指数（FTI）和睾酮分泌指数（TSI）。结果： 中年组SHBG、LH、HDL和LDL均低于老年组，FT、FTI、TSI高于老年组(P均0.05)。TT和SHBG与TG、TCH、HDL和LDL呈负相关，FT与TCH呈正相关，FTI与TG、TCH和LDL呈正相关，TSI与TCH、HDL和LDL呈正相关，LH与TG、TCH和LDL呈负相关(P均0.05)。多元线性回归分析显示TT和SHBG与TG、TCH、HDL、LDL仍呈负相关；LH与TCH、HDL和LDL呈负相关(P均0.05)。结论： 中老年男性血清TT、SHBG和LH降低有增加患高TC血症和高LDL血症风险，TT和SHBG降低有增加患高TG血症风险，而TT、SHBG和LH升高有增加患低HDL血症风险。.

Alzheimer disease (AD) is a neurodegenerative disease. Manganese (Mn) is an essential trace element in the human body. It can enter the brain through the blood-brain barrier and blood-cerebrospinal fluid barrier. Excessive accumulation of Mn in the brain may disturb the homeostasis of the central nervous system (CNS) microenvironment and cause severe neuronal damage. The most recent data suggest that excessive Mn is associated with impaired learning and memory in animal models, and may lead to irreversible and progressive mild cognitive impairment and AD. However, the mechanism for the involvement of Mn in AD pathogenesis remains controversial. This paper reviews the effects of Mn on CNS, mitochondrial function, p53 expression, and amyloid precursor protein/β-amyloid metabolism, and analyzes the relationship between these effects and AD pathogenesis.

To explore the longterm influence of vasectomy on the levels of serum androgens in aging males.Using stratified random sampling, we conducted a questionnaire survey and physical examinations among 437 adult males aged ≥40 years, 232 with and 205 without the history of vasectomy. In addition, we measured the levels of serum total testosterone (TT), sexhormone binding globulin (SHBG), calculated free testosterone (cFT), testosterone secreting index (TSI), free testosterone index (FTI), and luteinizing hormone (LH).Compared with the nonvasectomy group, the vasectomy group showed significantly increased levels of serum TT (［16.01±5.41］ vs ［17.39±6.57］ nmol/L), SHBG (［58.91±36.89］ vs ［70.28±40.90］ nmol/L), and LH (［8.86±6.49］ vs ［10.85±11.73］ IU/L) (all P0.05) and a decreased level of FTI (0.33±0.15 vs 0.30±0.12, P0.05). There were no statistically significant differences between the nonvasectomy and vasectomy groups in cFT (［0.24±0.07］ vs ［0.23±0.09］ nmol/L) or TSI (［2.42±1.34］ vs ［2.46±1.51］ nmol/IU) (both P0.05), nor after adjustment for relevant factors in TT (β: 1.015, 95% CI: －0.180－2.210), SHBG (β: 5.118, 95% CI: －2.069－12.305), cFT (β: 0.003, 95% CI: －0.011－0.018), FTI (β: －0.012, 95% CI: －0.035－0.011), TSI (β: 0.138, 95% CI: －0.131－0.407), and LH (β: 1.011, 95% CI: －0.811－2.834) (all P0.05).Vasectomy has no obvious longterm influence on the levels of serum androgens in aging males.目的： 探讨输精管结扎术对男性中老年期血清雄激素水平的远期影响。 方法： 采用分层整群抽样的方法，抽取遵义地区40岁及以上成年男性437例(有输精管结扎史232例，无结扎史205例)进行问卷调查、体格检查，并检测其血清总睾酮(TT)、性激素结合球蛋白(SHBG)和黄体生成素(LH)，计算游离睾酮(cFT)、睾酮分泌指数(TSI)、游离睾酮指数(FTI)。结果： 结扎组TT(17.39±6.57) nmol/L、SHBG(70.28±40.90) nmol/L和LH(10.85±11.73) IU/L均显著高于非结扎组的(16.01±5.41) nmol/L、(58.91±36.89) nmol/L和(8.86±6.49) IU/L,P均0.05；结扎组FTI(0.30±0.12)显著低于非结扎组(0.33±0.15) ，P0.05；结扎组cFT(0.23±0.09) nmol/L、TSI(2.46±1.51) nmol/IU与非结扎组(0.24±0.07) nmol/L、(2.42±1.34) nmol/IU相比，差异无统计学意义（P均0.05）。校正相关因素后，结扎组与非结扎组相比，TT(β:1.015,95%CI:－0.180,2.210)、SHBG(β:5.118,95%CI:－2.069,12.305)、cFT(β:0.003,95%CI:－0.011,0.018)、FTI(β:－0.012,95%CI:－0.035，0.011)、TSI(β:0.138,95%CI:－0.131,0.407)、LH(β:1.011,95%CI:－0.811,2.834)差异均无统计学意义(P均0.05)。结论： 输精管结扎术对男性中老年期血清雄激素水平未见明显的远期影响。.

A Modified Cam-Clay Model and finite element methods (FEM) are used in this paper to analyze the deformation and settlement of red clay foundation. The results show: (1)The deformation of oil tank foundation calculated is close to that measured and the effect of geometric nonlinearity is small. (2) Geometry of loading and level of stress have important effects on the deformation behaviors of red clay foundations. In practice the result of elastic-plastic FEM is much better than that of classical calculated methods (CCM).

To evaluate the efficacy and safety of testosterone undecanoate (TU) in the treatment of late-onset hypogonadism (LOH) by meta-analysis.We searched Pubmed (until April 1, 2014), Embase (until March 28, 2014), Cochrane Library (until April 17, 2014), CBM (from January 1, 2001 to February 2, 2014), CNKI (from January 1, 2001 to February 2, 2014), Wanfang Database (from January 1, 2000 to February 2, 2014), and VIP Database (from January 1, 2000 to Febru ary 2, 2014) for randomized controlled trials of TU for the treatment of LOH. We evaluated the quality of the identified literature and performed meta-analysis on the included studies using the Rveman5. 2 software.Totally, 14 studies were included after screening, which involved 1 686 cases. Compared with the placebo and blank control groups, TU treatment significantly increased the levels of serum total testosterone (SMD = 6.22, 95% CI 3.99 to 8.45, P0.05) and serum free testosterone (SMD = 4.35, 95% CI 1.86 to 6. 85, P0.05) but decreased the contents of luteinizing hormone (WMD = -2.23, 95% CI -4.03 to -0.42, P0.05), sex hormone binding globulin (WMD = 2.00, 95% CI 1.38 to 2.63, P0.05). TU also remarkably reduced the scores of Partial Androgen Deficiency of the Aging Males (WMD = -9.49, 95% CI -12.96 to -6.03, P0.05) and Aging Males Symptoms rating scale (WMD = -2.76, 95% CI -4.85 to -0.66, P0.05) but increased the hemoglobin level (SMD = 2.35, 95% CI 0.29 to 4.41, P0.05) and packed-cell volume (SMD = 4.35, 95% CI 1.36 to 7.33, P0.05). However, no significant changes were shown in aspertate aminotransferase, alanine transaminase, prostate-specific antigen, or prostate volume after TU treatment (P0.05).TU could significantly increase the serum testosterone level and improve the clinical symptoms of LOH patients without inducing serious adverse reactions. However, due to the limited number and relatively low quality of the included studies, the above conclusion could be cautiously applied to clinical practice.

To evaluate the effect and safety of L-carnitine in the treatment of idiopathic oligoasthenozoospermia based on current clinical evidence.We searched the Cochrane Library, PubMed, MEDLINE, EMBASE, CNKI, VIP, CBM and Wanfang Database from the establishment to April 2014 for the published literature on the treatment of idiopathic oligoasthenozoospermia with L-carnitine. We conducted literature screening, data extraction, and assessment of the methodological quality of the included trials according to the inclusion and exclusion criteria, followed by statistical analysis with the RevMan 5. 2 software.Seven randomized controlled trials involving 751 patients with idiopathic oligoasthenozoospermia met the inclusion criteria, and 678 of them were included in the meta-analysis. L-carnitine treatment achieved a significantly increased rate of spontaneous pregnancy as compared with the control group (RR = 3.2, 95% CI 1.74 to 5.87, P = 0.0002). After 12-16 and 24-26 weeks of medication, total sperm motility (WMD = 5.21, 95% CI 2.78 to 7.64, P0.0001 and WMD = 9.29, 95% CI 1.28 to 17.29, P = 0.02) and the percentage of progressively motile sperm (WMD = 12.44, 95% CI 4.58 to 20.31, P = 0.002 and WMD = 9.76, 95% CI 3.56 to 15.97, P = 0.002) were remarkably higher than those in the control group, but no statistically significant differences were observed in sperm concentration between the two groups (WMD = 4.91, 95% CI -2.63 to 12.45, P = 0.2 and WMD = 0.93, 95% CI -3.48 to 5.34, P = 0.68). After 12-16 weeks of treatment, the percentage of morphologically abnormal sperm was markedly decreased in the L-carnitine group as compared with the control (WMD = -2.48, 95% CI -4.35 to -0.61, P = 0.009), but showed no significant difference from the latter group after 24-26 weeks (WMD = -4.38, 95% CI -9.66 to 0.89, P = 0.1). No statistically significant difference was found in the semen volume between the two groups after 12-16 or 24-26 weeks of medication (WMD = -0.13, 95% CI -0.43 to 0.18, P = 0.42 and WMD = 0.28, 95% CI -0.02 to 0.58, P = 0.07). No serious L-carnitine-related adverse events were reported in 4 of the randomniized controlled trials.The current evidence indicates that L-carnitine can improve spontaneous pregnancy and semen parameters in the treatment of idiopathic oligoasthenozoospermia, with no serious adverse reactions.

To explore the biomarker of manganese exposure by analyzing the relationship between manganese exposure and concentration in some biomaterials.The air samples were collected through the individual air sample. According to the manganese levels in the air, workers were assigned to control group, low concentration group and high concentration group, and manganese in the hair, urine, serum, blood cell and saliva from different group were measured respectively. The correlations between concentration of external manganese exposure and manganese concentrations in biomaterials, and years of employment and concentrations in biomaterials were analyzed.In the high concentration group, saliva manganese was 32.17 µg/L, hair manganese was 37.39 mg/kg, urine manganese was 2.50 µg/L, plasma manganese was 29.61 µg/L, blood manganese was 14.49 µg/L, were higher than those in the control group (10.40 µg/L, 1.60 mg/kg, 0.77 µg/L, 10.30 µg/L, 4.56 µg/L respectively) (P0.01). The manganese concentration in the saliva was significantly correlated with airborne manganese concentration (r = 0.649, P0.01), with the years of employment (r = 0.404, P0.01), with the total exposure of manganese (r = 0.342, P0.01), with the manganese concentration of plasma (r = 0.303, P0.01) and with the manganese concentration in blood cells (r = 0.359, P0.01), respectively.The concentration of manganese in saliva could work as a biomarker of manganese internal exposure.

In order to ascertain prevalence rate of premarital sexual intercourse, unintended pregnancy and abortion, and evaluate associated factors of unintended pregnancy among undergraduates from all over China, the representative sample of unmarried undergraduates was obtained by using a multi-stage, stratified, probability cluster design, and data were collected by using a survey questionnaire. 62 326 available responders were gained. 11.6% of them acknowledged having experiences of premarital sexual intercourse (standardized prevalence rate of sexual intercourse was 13.8%). 31.5% of students active in premarital sex acknowledged undergoing unintended pregnancy. 76.2% of pregnant students selected abortion to end it. Of students active in premarital sex, 46.2% used contraception at the first sexual intercourse, 28.2% replied “always” using contraception in sexual intercourse. The rate of using condoms, oral contraceptives (OCs), and withdrawal among students who had used contraception was 52.0%, 31.0%, and 27.2% respectively. “No preparation for sex” (40.3%), “pleasure decrement” (32.1%), “won’t-be-pregnancy in occasional sexual intercourse” (30.2%) were their common excuses for using no contraception. The identified risk factors for unintended pregnancy among students active in premarital sex by multivariate analysis were as follows: having no steady lover [having no steady lover vs having a steady lover: odds ratio (OR), 1.875; 95% confidence interval (CI), 1.629–2.158], unaware of the course of conception (unaware vs aware: OR, 2.023; 95% CI, 1.811–2.260), considering abortion not endanger women’s physical and mental health (no endangerment vs endangerment: OR, 2.659; 95% CI, 2.265–3.121), nonuse of contraception (never use vs always use: OR, 1.682; 95% CI, 1.295–2.185). Medical students were not less likely to experience an unintended pregnancy than nonmedical students (OR, 1.111; 95% CI, 0.906–1.287). The substantial proportion of unintended pregnancy among undergraduates indicates a need for convenient and targeted contraceptive education and services.