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1.
Environ Sci Technol ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34813313

RESUMO

Disinfection byproduct (DBP) exposure has been associated with birth size, pregnancy oxidative stress, and other adverse perinatal outcomes. However, little is known about the potential effect of prenatal DBP exposure on intrauterine growth. The present study included 1516 pregnant women from the Xiaogan Disinfection By-Products (XGDBP) birth cohort who were measured for four blood trihalomethanes [i.e., chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM)] and two urinary haloacetic acids [i.e., dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA)] across pregnancy trimesters. Second- and third-trimester fetal ultrasound measures of the abdominal circumference (AC), head circumference, biparietal diameter, femur length, and estimated fetal weight and birth weight were converted into z-scores. After adjusting for potential confounders, linear mixed models showed a decreasing AC z-score across tertiles of blood brominated THM (Br-THMs, the sum of BDCM, DBCM, and TBM) and total THM (THM4, the sum of Br-THMs and TCM) concentrations (both p for trend <0.01). We also observed a decreasing AC z-score across categories of blood TBM during pregnancy trimesters (p for trend = 0.03). Urinary haloacetic acids were unrelated to fetal growth parameters. In summary, prenatal exposure to THMs, particularly during the first trimester, was associated with reduced fetal abdominal circumference.

2.
Fertil Steril ; 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34656302

RESUMO

OBJECTIVE: To explore the association between depression and semen quality and the mediating role of oxidative stress. DESIGN: Cross-sectional study with repeated measures of semen quality. SETTING: Human Sperm Bank of Hubei Province, People's Republic of China. PATIENT(S): From April 2017 to July 2018, we recruited 1,000 potential sperm donors who completed the Beck Depression Inventory questionnaire and had measures of oxidative stress biomarkers. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Severity of depression was evaluated by the Beck Depression Inventory scores (0-4, no depression; 5-13, mild depression; 14-20, moderate depression; and 21 or greater, severe depression). The urinary concentrations of 8-hydroxy-2-deoxyguanosine, 4-hydroxy-2-nonenal-mercapturic acid, and 8-iso-prostaglandin F2α (8-isoPGF2α) were measured to reflect oxidative stress status. Repeated semen quality parameters (n = 5,880) were examined by trained professional technicians according to the World Health Organization laboratory manual. Associations between depression, oxidative stress, and repeated measures of semen quality parameters were evaluated using linear or mixed-effects models with adjustment for potential confounders. Mediation analysis was performed to test the potential mediating role of oxidative stress. RESULT(S): A total of 391 (39.1%) men were classified as mild depression, 67 (6.7%) as moderate depression, and 19 (1.9%) as severe depression. Inverse dose-response relationships between severity of depression and semen quality parameters were found. Compared with men without depression (n = 523), those with severe depression had a 25.26% (95% confidence interval, -38.65%, -8.93%) lower semen volume, 37.04% (-55.37%, -11.20%) lower total sperm count, 13.57% (-23.17%, -2.78%) lower total motility, and 15.08% (-25.09%, -3.72%) lower progressive motility; men with moderate depression also had a 12.28% (-21.16%, -2.40%) lower semen volume and 23.56% (-36.50%, -7.97%) lower total sperm count. We found a positive dose-response relationship between severity of depression and urinary 8-isoPGF2α concentrations. However, we found no evidence that the associations between depression status and semen quality were mediated by oxidative stress markers. CONCLUSION(S): In the study of Chinese male sperm donors, men with depression had worse semen quality parameters, including semen volume, sperm concentration, total sperm count, total motility, and progressive motility. Although depression was positively associated with urinary 8-isoPGF2α concentrations, depression-semen quality associations were not mediated by oxidative stress.

3.
Environ Int ; 157: 106838, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34450548

RESUMO

BACKGROUND: Toxicological studies suggest that maternal exposure to disinfection by-products (DBPs) can impair fetal neurodevelopment. However, evidence from epidemiological studies is scarce and the underlying mechanisms remain unclear. OBJECTIVE: To explore the trimester-specific associations between maternal blood trihalomethane (THM) and urinary haloacetic acid (HAA) concentrations and neonatal neurobehavioral development, and the potential mediating role of oxidative stress (OS). METHODS: We included 438 pregnant Chinese women from the Xiaogan Disinfection By-Products (XGDBP) birth cohort. Biospecimens were repeatedly collected across trimesters and measured for blood THMs, urinary HAAs, and urinary OS biomarker concentrations. On the third day after birth, the Neonatal Behavioral Neurological Assessment (NBNA) test was administered to newborns. Associations of trimester-specific DBP measurements and OS biomarkers with neonatal NBNA scores were assessed using linear regression models with generalized estimating equations. The potential mediating role of maternal OS biomarkers was also investigated using mediation analyses. RESULTS: After adjusting for potential confounders, blood bromodichloromethane (BDCM) concentrations in the first trimester were inversely associated with NBNA scores [percent change comparing the extreme BDCM tertiles = -28.1% (95% CI: -55.2%, -0.88%); p for trend = 0.043]. Besides, third-trimester urinary trichloroacetic acid (TCAA) concentrations were inversely associated with NBNA scores [percent change comparing the extreme TCAA tertiles = -32.9% (95% CI: -64.7%, -1.0%); p for trend = 0.046]. These inverse associations differed across pregnancy trimesters (Type 3p-value = 0.066 and 0.053, respectively) and were stronger in male infants and mothers aged ≥25 years. There was no evidence of mediating effect by 8-hydroxy-2-deoxyguanosine (8-OHdG), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), or 8-iso-prostaglandin F2α (8-isoPGF2α). CONCLUSIONS: Higher prenatal BDCM and TCAA concentrations during specific pregnancy trimesters were associated with lower NBNA scores. However, additional research is required to investigate underlying mechanisms.


Assuntos
Desinfecção , Exposição Materna , Feminino , Humanos , Recém-Nascido , Masculino , Exposição Materna/efeitos adversos , Estresse Oxidativo , Gravidez , Trimestres da Gravidez , Ácido Tricloroacético , Trialometanos/toxicidade
5.
Sci Rep ; 11(1): 9491, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947884

RESUMO

Obesity increases the risk of developing cardiovascular disease and other metabolic diseases. We intended to compare three different anthropometric indicators of obesity, in predicting the incidence of cardiovascular events in Chinese type 2 diabetes. Beijing Community Diabetes Study was a prospective multi-center study conducted in Beijing community health centers. Type 2 diabetes patients from fourteen community health centers were enrolled at baseline. The primary endpoint was cardiovascular events. The upper quartile of neck circumference (NC) was set as greater NC. A total of 3299 diabetes patients were enrolled. In which, 941 (28.52%) had cardiovascular disease at baseline. Logistic analysis showed that central obesity (waist circumference (WC) above 90 cm in men and 85 cm in women) and greater NC were all related to baseline cardiovascular disease (adjusted OR = 1.49, and 1.55). After 10-year follow-up, 340 (10.31%) had cardiovascular events. Compared with patients without cardiovascular events, those having cardiovascular events had higher BMI, larger WC and NC. Cox regression analysis showed that greater WC and NC were all associated with the occurrence of cardiovascular events (adjusted HR = 1.41, and 1.38). A higher NC and WC might increase the risk of cardiovascular events by about 40% in type 2 diabetes patients in Beijing communities.


Assuntos
Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Pescoço/fisiologia , Circunferência da Cintura/fisiologia , Idoso , Antropometria/métodos , Pequim , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/complicações , Obesidade Abdominal/fisiopatologia , Estudos Prospectivos , Fatores de Risco
6.
Environ Int ; 155: 106586, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33910075

RESUMO

BACKGROUND: Essential elements such as iron (Fe), cobalt (Co), copper (Cu), zinc (Zn), selenium (Se), rubidium (Rb), strontium (Sr), and molybdenum (Mo) are necessary for reproductive health. However, their associations with human semen quality remain inconclusive. OBJECTIVES: To investigate the associations of urinary Fe, Co, Cu, Zn, Se, Rb, Sr, and Mo concentrations with semen quality in healthy men screened as potential sperm donors and identify critical windows of susceptibility. METHODS: 1428 healthy men provided 3766 urine and 6527 semen samples, which were measured for urinary essential element concentrations and sperm quality parameters, respectively. Linear mixed models and cubic spline curves were used to evaluate associations between urinary essential elements and semen quality. Multiple informant models were used to identify potential critical windows of susceptibility. RESULTS: Linear mixed models and cubic spline curves showed positive dose-response relationships between urinary Zn and sperm concentration and total count and between urinary Mo and total sperm count [all False Discovery Rate (FDR) adjusted p-value for trend < 0.05]. In the multiple-element linear mixed models, the men in the highest versus lowest quartiles of urinary Zn and Mo had a higher sperm concentration of 17.5% (95% CI: 2.8%, 34.2%; p-value for trend = 0.006) and total sperm count of 18.3% (95% CI: 1.4%, 38.0%; p-value for trend = 0.027), respectively. Urinary Zn was also positively associated with total sperm count in a dose-dependent manner (p-value for trend = 0.036), though the percentile difference in total sperm count between men in the highest and lowest quartile was not statistically significant (16.4%, 95% CI: -1.7%, 37.9%). These associations appeared to be stronger when urinary Zn and Mo were measured at 0-9 days before the date of semen examination (i.e., corresponding to epididymal storage). CONCLUSIONS: Higher urinary Zn and Mo, particularly during the period of epididymal storage, were associated with greater sperm production.


Assuntos
Selênio , Análise do Sêmen , Humanos , Masculino , Sêmen , Contagem de Espermatozoides , Motilidade Espermática , Espermatozoides
7.
World J Clin Cases ; 9(8): 1901-1908, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748240

RESUMO

BACKGROUND: Leptospira is an uncommon pathogen for adult severe community-acquired pneumonia and its nonspecific manifestations and limited diagnostic tests make it difficult to identify. Although conventional penicillin remains efficacious to treat leptospirosis, failure in early diagnosis and treatment can lead to progression into a deadly syndrome with multiple organ dysfunction. Next generation sequencing is of great value to understand cases with infection of unknown cause, which could help in the diagnosis of uncertain Leptospira infection. CASE SUMMARY: We recently managed a patient with fever, cough and dyspnea on admission that progressed into persistent adult respiratory distress syndrome, hemoptysis and hematuria after admission. In this case, the rare Leptospira infection was clouded by the positive influenza tests at admission, delaying early Leptospira-targeted antibiotics administration. Next generation sequencing, a novel molecular diagnostic tool, provided a key hint to uncover the crucial pathogen, Leptospira interrogans, further supported by the possible occupational exposure history. Subsequent conventional penicillin and mechanical respiratory support were administrated to cure the patient successfully without any sequela. CONCLUSION: Clinicians must pay attention to possible exposure history and keep uncommon Leptospira in mind when managing pneumonia with unknown causes.

8.
Sci Rep ; 11(1): 4839, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649485

RESUMO

To investigate the potential benefits of acarbose therapy on cardiovascular events (CVD) in Type 2 diabetes (T2DM) in an urban community over 10-year follow-up. The study population of Beijing Community Diabetes Study (BCDS) were type 2 diabetes (T2DM) living in 21 communities in Beijing. All patients received comprehensive intervention in accordance with the Chinese guidelines for the prevention and treatment of diabetes. Professors in endocrinology from top tier hospitals regularly visited the communities for consultations, which was a feature of this study. A total of 1797 T2DM in BCDS study had complete screening data, including blood glucose, blood pressure, lipid profiles and acarbose continuous therapy. After 10-year follow-up, the risks of CVD outcomes were assessed according to whether patients had received acarbose therapy or not. All patients were followed-up to assess the long-term effects of the multifactorial interventions. At baseline, compared with the acarbose therapy free in T2DM, there was no significant difference in achieving the joint target control in patients with acarbose therapy. From the beginning of 8th year follow-up, the joint target control rate in patients with acarbose therapy was significantly higher than that of acarbose therapy free. During the 10-year follow-up, a total of 446 endpoint events occurred, including all-cause death, cardiovascular events, cerebrovascular events. The incidences of myocardial infarction (from the 4th year of follow-up) and all-cause death (from the 2nd year of follow-up) in patients who received acarbose therapy were significantly lower than that of acarbose therapy free respectively. In Cox multivariate analyses, there were significant differences in incidences of myocardial infarction and all-cause death between afore two groups during the 10-year follow-up, and the adjusted HRs were 0.50 and 0.52, respectively. After multifactorial interventions, T2DM with acarbose therapy revealed significant reductions of myocardial infarction and all-cause death. The long-term effects of with acarbose therapy on improving joint target control might be one of the main reasons of myocardial infarction and all-cause death reduction.Trial Registration: ChiCTR-TRC-13003978, ChiCTR-OOC-15006090.

10.
Environ Health Perspect ; 128(10): 107001, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33026246

RESUMO

BACKGROUND: Some disinfection by-products (DBPs) are reproductive and developmental toxicants in laboratory animals. However, studies of trimester-specific DBP exposure on adverse birth outcomes in humans are inconsistent. OBJECTIVE: We examined whether trimester-specific blood and urinary biomarkers of DBP were associated with small for gestational age (SGA), low birth weight (LBW), and preterm birth. METHODS: A total of 4,086 blood and 3,951 urine samples were collected across pregnancy trimesters among 1,660 mothers from Xiaogan City, China. Blood samples were quantified for biomarkers of trihalomethanes (THMs): chloroform (TCM), bromodichloromethane, dibromochloromethane, and bromoform. Urine samples were quantified for biomarkers of haloacetic acids (HAA): dichloroacetic acid and trichloroacetic acid. Birth outcomes were abstracted at delivery from medical records. We used Poisson regression models with log link functions to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for SGA, LBW, and preterm birth across tertiles (or categories) of DBP biomarker concentrations measured across pregnancy trimesters. We also examined the relative exposure differences across gestation comparing adverse outcomes with normal births using mixed-effects models. RESULTS: Blood TCM concentrations in the second trimester were associated with an elevated risk of SGA comparing middle vs. lowest (RR, 2.34; 95% CI: 1.02, 5.35) and highest vs. lowest (RR, 2.47; 95% CI: 1.09, 5.58) exposure groups. Third-trimester blood TCM concentrations were also associated with an increased risk of SGA comparing the second tertile with the first (RR, 2.61; 95% CI: 1.15, 5.92). We found that maternal blood TCM concentrations were significantly higher for SGA compared with non-SGA births across the period from 23 to 34 wk gestation. Other blood and urinary DBP biomarkers examined were unrelated to SGA, LBW, or preterm birth. CONCLUSION: Blood TCM concentrations in mid to late pregnancy were associated with an increased risk of SGA, whereas other biomarkers of DBPs examined across pregnancy were not associated with birth outcomes. https://doi.org/10.1289/EHP7195.


Assuntos
Desinfetantes/metabolismo , Hidrocarbonetos Clorados/urina , Exposição Materna/estatística & dados numéricos , Complicações do Trabalho de Parto/epidemiologia , Trialometanos/sangue , Poluentes Químicos da Água/metabolismo , Adulto , Peso ao Nascer , China/epidemiologia , Desinfecção , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Razão de Chances , Gravidez , Terceiro Trimestre da Gravidez , Trimestres da Gravidez , Nascimento Prematuro
11.
Environ Int ; 137: 105518, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32018134

RESUMO

BACKGROUND: Toxicological studies have demonstrated that disinfection by-products (DBPs) can induce oxidative stress, a proposed mechanism that is relevant to adverse birth outcomes. OBJECTIVE: To examine the associations of blood trihalomethanes (THMs) and urinary haloacetic acids (HAAs) with urinary biomarkers of oxidative stress among pregnant women. METHODS: From 2015 to 2017, a total of 4150 blood and 4232 urine samples were collected from 1748 Chinese women during pregnancy. We determined concentrations of 4 blood THMs [chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM)] and 2 urinary HAAs [dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA)]. The summary measures of exposure for brominated THMs (Br-THMs; a molar sum of BDCM, DBCM, and TBM) and total THMs (TTHMs; a molar sum of TCM and Br-THMs) were also calculated. Associations of categorical (i.e., tertiles) and continuous measures of DBPs with urinary concentrations of oxidative stress (OS) biomarkers, 8-hydroxy-2-deoxyguanosine (8-OHdG), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), and 8-iso-prostaglandin F2α (8-isoPGF2α), were assessed using linear mixed regression models. RESULTS: After adjusting for relevant confounding factors, we observed positive dose-response relationships between blood Br-THM tertiles and urinary HNE-MA (P for trend < 0.001). We also found positive associations between tertiles of blood TCM and TTHMs and urinary 8-OHdG and HNE-MA (all P for trend < 0.05). Urinary HAAs were also positively associated with 8-OHdG, HNE-MA, and 8-isoPGF2α in a dose-response manner (all P for trend < 0.001). These associations were further confirmed when we modeled DBP exposures as continuous variables in linear mixed regression models, as well as in penalized regression splines based on generalized additive mixed models. CONCLUSIONS: Exposure to DBPs during pregnancy may increase maternal OS status.


Assuntos
Desinfetantes , Estresse Oxidativo , Efeitos Tardios da Exposição Pré-Natal , Ácido Tricloroacético , Trialometanos , Poluentes Químicos da Água , Biomarcadores , Desinfecção , Feminino , Humanos , Gravidez , Trialometanos/sangue
12.
Environ Int ; 135: 105368, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31830732

RESUMO

BACKGROUND: Short sleep duration and poor sleep quality are increasingly prevalent in modern society and may be associated with impaired semen quality, yet studies are inconclusive. OBJECTIVES: To investigate the reproducibility of semen quality parameters among 842 healthy men screened as potential sperm donors and explore the associations of sleep duration and quality with repeated measures of semen quality parameters. METHODS: We assessed sleep duration (night sleep and daytime napping) and sleep quality using the Pittsburgh Sleep Quality Index (PSQI) among 842 healthy men screen as potential sperm donors. We examined sleep characteristics in relation to repeated measurements (n = 5601) of semen parameters using linear mixed-effects models. RESULTS: High degrees of within-individual variability were found for total and progressive sperm motility with intraclass correlation coefficient (ICC) of 0.20 and 0.22, respectively; while fair-to-good reproducibilities were observed for sperm volume, concentration, and total count (ICC = 0.54, 0.62, and 0.50, respectively). Compared to men with total sleep duration of 8.0-8.5 h/day (h/d), men who slept less than 6.0 h/d and higher than 9.0 h/d had lower sperm volume of 12% [95% confidence interval (CI): -22%, -0.68%] and 3.9% (95% CI: -7.3%, -0.44%), respectively. Compared to men with night sleep duration of 7.5-8.0 h/d, men who slept less than 6.0 h/d had lower total and progressive sperm motility of 4.4% (95 CI:-8.4%, -0.24%) and 5.0% (95% CI: -9.2%, -0.48%), respectively. Compared to men who reported good sleep quality (total PSQI score ≤5.0), those reporting poor sleep quality (total PSQI score >5.0) had lower total sperm count, total motility, and progressive motility of 8.0% (95% CI: -15%, -0.046%), 3.9% (95% CI: -6.2%, -1.5%), and 4.0% (95% CI: -6.5%, -1.4%), respectively. CONCLUSIONS: Both long and short sleep duration and poor sleep quality were associated with impaired semen quality parameters. The high within-individual variability of total and progressive sperm motility suggests that a single measurement may result in a moderate degree of classification error.


Assuntos
Análise do Sêmen , Motilidade Espermática , Humanos , Masculino , Reprodutibilidade dos Testes , Sêmen , Contagem de Espermatozoides
13.
Environ Int ; 134: 105335, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783240

RESUMO

BACKGROUND: Trihalomethanes (THMs) have demonstrated adverse effects on male reproductive systems in experimental animals, but human evidence has been inconsistent. Prior researches have been limited by small sample sizes and inadequate exposure assessment. OBJECTIVES: To investigate the association between blood THMs and repeated measurements of semen quality parameters among 1199 healthy men screened as potential sperm donors. METHODS: We recruited healthy men presenting to the Hubei Province Human Sperm Bank from April to December 2017. At study entry, each participant provided a spot blood sample which was used to quantify blood concentrations of four THMs: chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM) and bromoform (TBM). The summary measures of exposure for brominated THMs (Br-THMs; molar sum of BDCM, DBCM and TBM) and total THMs (TTHMs; molar sum of TCM and Br-THMs) were also calculated. We used multivariable linear regression models to estimate the cross-sectional associations of tertiles of blood THM concentrations with semen quality parameters measured at study entry, and mixed-effect models to estimate the longitudinal associations accounting for repeated measures of semen quality, adjusting for relevant confounding factors. RESULTS: In the cross-sectional analysis, several inverse dose-response relationships were observed across tertiles of blood TCM concentrations and sperm count, total motility and progressive motility, and between blood DBCM, and Br-THMs, and TTHMs and sperm count and concentration. The inverse associations of blood TCM, DBCM, Br-THMs and TTHMs with sperm count were confirmed in the longitudinal, repeated measure analysis. CONCLUSION: Our results suggest that exposure to THMs from drinking water may be related to decreased semen quality in young healthy men.


Assuntos
Água Potável/química , Análise do Sêmen , Trialometanos/sangue , Poluentes Químicos da Água/sangue , China , Estudos Transversais , Humanos , Masculino , Espermatozoides/efeitos dos fármacos , Trialometanos/efeitos adversos , Poluentes Químicos da Água/efeitos adversos
14.
Hum Reprod ; 34(12): 2330-2339, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31858122

RESUMO

STUDY QUESTION: Is physical activity or sedentary time associated with semen quality parameters? SUMMARY ANSWER: Among healthy men screened as potential sperm donors, higher self-reported physical activity was associated with increased progressive and total sperm motility. WHAT IS KNOWN ALREADY: Despite the claimed beneficial effect of moderate physical activity on semen quality, results from epidemiological studies have been inconclusive. Previous studies were mostly conducted among endurance athletes or male partners of couples who sought infertility treatment. STUDY DESIGN, SIZE, DURATION: Healthy men screened as potential sperm donors were recruited at the Hubei Province Human Sperm Bank of China. Between April 2017 and July 2018; 746 men completed the long-form International Physical Activity Questionnaire (IPAQ) and provided repeated semen samples (n = 5252) during an approximately 6-month period. PARTICIPANTS/MATERIALS, SETTING, METHODS: Total metabolic equivalents (METs), moderate-to-vigorous METs and sedentary time were abstracted from the IPAQ. Sperm concentration, total sperm count, progressive motility and total motility in repeated specimens were determined by trained clinical technicians. Mixed-effect models were applied to investigate the relationships between physical activity and sedentary time and repeated measures of semen quality parameters. MAIN RESULTS AND THE ROLE OF CHANCE: After adjusting for multiple confounders, total METs and moderate-to-vigorous METs were both positively associated with progressive and total sperm motility. Compared with men in the lowest quartiles, those in the highest quartiles of total and moderate-to-vigorous METs had increased progressive motility of 16.1% (95% CI: 6.4, 26.8%) and 17.3% (95% CI: 7.5, 27.9%), respectively, and had increased total motility of 15.2% (95% CI: 6.2, 24.9%) and 16.4% (95% CI: 7.4, 26.1%), respectively. Sedentary time was not associated with semen quality parameters. LIMITATIONS, REASONS FOR CAUTION: The IPAQ was reported only once from study participants; measurement errors were inevitable and may have biased our results. Furthermore, although we have adjusted for various potential confounders, the possibility of unmeasured confounding cannot be fully ruled out. WIDER IMPLICATIONS OF THE FINDINGS: Our findings suggest that maintaining regular exercise may improve semen quality parameters among healthy, non-infertile men. Specifically, we found that higher self-reported total and moderate-to-vigorous METs were associated with improved sperm motility, which reinforces the existing evidence that physical activity may improve male reproductive health. STUDY FUNDING/COMPETING INTEREST(S): Y.-X.W was supported by the Initiative Postdocs Supporting Program (No. BX201700087). A.P. was supported by the National Key Research and Development Program of China (2017YFC0907504). C.-L.X. was supported by the National Key Research and Development Program of China (2016YFC1000206). The authors report no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Exercício Físico , Comportamento Sedentário , Contagem de Espermatozoides/estatística & dados numéricos , Motilidade Espermática , Adulto , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
15.
Huan Jing Ke Xue ; 40(10): 4404-4411, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854807

RESUMO

Intermediate-volatility organic compounds (IVOCs) are important precursors of secondary organic aerosols that have received much recent attention; however, there is a lack of emission data for IVOCs from combustion sources, especially for residential solid fuel combustion. In this study, two bituminous coals with different geological maturity (XZ and LW) and two biomass types (rice stalk and pinewood) were tested at seven temperature points (300-900℃ with an interval of 100℃) using a quartz tube furnace together with a dilution sampling system. The results showed that the averaged emission factor for IVOCs from biomass combustion[(483±182) mg·kg-1] was 2.5 times higher than that of bituminous coal combustion (190±108) mg·kg-1. The remaining unresolved complex mixture (UCM) dominated the IVOC content for both biomass and coal combustions (81%±11% and 68%±6%, respectively). The fraction of normal and branched alkanes for biomass combustions was lower than for coal combustion, while the fraction of aromatics was higher. The effect of temperature on the emission of IVOCs and their composition was significantly different between the two types of fuel. The emission factor for IVOCs from coal (using LW as an example) at 500℃[(340±113) mg·kg-1] was 5.4 times higher than at 900℃[(63±15) mg·kg-1], while two comparable peaks are observed at 400-500℃ and 800-900℃. As the combustion temperature increased, the proportion of aromatic hydrocarbons in pinewood IVOCs increased from 1% to 29%, while the remaining UCM decreased from 92% to 61%. However, there was little variation for coal combustion. The effects of fuel type and temperature on the emission of IVOCs were further explained with respect to the modified combustion efficiency (MCE).

16.
Biomed Res Int ; 2019: 4242304, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886212

RESUMO

Background: Neck circumference (NC) was found to be related to the risk factors of cardiovascular disease. However, the effects of NC on cardiovascular disease are still controversial. A prospective study of Chinese patients with type 2 diabetes was performed to evaluate the relationship between NC and cardiovascular disease. Methods: A multicenter prospective study with eight-year follow-up was conducted in Beijing communities. Cardiovascular events were defined as myocardial infarction, unstable angina pectoris, hospitalization for heart failure, coronary revascularization, cardiac death, stroke, transient ischemic attack, and cerebral hemorrhage. Results: A total of 3,009 diabetic patients were recruited. Following an eight-year follow-up, 211 patients with cardiovascular events (105 in men and 106 in women) were identified. All patients were categorized into two groups according to the upper quartile of NC (43 cm in men and 39 cm in women). The prevalence of cardiovascular events in men with an NC >43 cm (16.48%) was higher than that in the group with an NC <43 cm (8.16%, p=0.007). The prevalence of cardiovascular events in women with the NC >39 cm (10.67%) was higher compared to the group with NC <39 cm (5.31%, p=0.004). The longitudinal prevalence of cardiovascular events in groups with different NC increased with the increasing duration of follow-up (p < 0.001). Cox regression analysis showed that higher NC was associated with the occurrence of cardiovascular events after adjusting for confounding variables (adjusted HR = 2.305 (1.535-3.460)). Conclusions: NC was associated with the occurrence of cardiovascular events in type 2 diabetes in Chinese communities, and greater NC may increase the risk of cardiovascular events by about 2.3-fold.


Assuntos
Doenças Cardiovasculares/patologia , Complicações do Diabetes/patologia , Diabetes Mellitus Tipo 2/patologia , Pescoço/patologia , Adulto , Pequim/epidemiologia , Doenças Cardiovasculares/epidemiologia , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores Sexuais
17.
Environ Res ; 179(Pt A): 108778, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31629946

RESUMO

BACKGROUND: Emerging evidence from animals indicates that oxidative stress plays a crucial role in the effects of phthalate exposure on male reproductive dysfunctions, which has never been thoroughly explored in humans. OBJECTIVE: To explore the potential mediating role of oxidative stress in the association of phthalate exposure with semen quality among 1034 Chinese men. METHOD: Repeated urine samples gathered from the male partners of sub-fertile couples were analyzed for 3 oxidative stress markers [8-hydroxy-2-deoxyguanosine (8-OHdG), 8-iso-prostaglandin F2α (8-isoPGF2α) and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA)], using a liquid chromatography-tandem mass spectrometry. Multivariate regression models were constructed to evaluate the associations of urinary oxidative stress markers with urinary phthalate metabolites and semen quality. We also explored the potential mediation effects by oxidative stress markers. RESULTS: Significantly positive dose-dependent relationships were observed between each individual phthalate metabolite and all analyzed oxidative stress markers (all p for trend<0.05), except for monoethyl phthalate (MEP) in relation to HNE-MA. Additionally, significantly or suggestively inverse dose-dependent relationships were exhibited between urinary 8-isoPGF2α and sperm concentration (p for trend = 0.05), and between urinary 8-OHdG and percent of normal sperm morphology (p for trend = 0.01). Mediation analysis showed that urinary 8-isoPGF2α suggestively mediated 12% of the inverse association between monobutyl phthalate (MBP) and sperm concentration, and that urinary 8-OHdG suggestively mediated 32% of the inverse association of MEP with percent of normal sperm morphology (both p < 0.10). CONCLUSIONS: Although further investigations are required, our results suggest that oxidative stress may play a mediating role in the effects of phthalate exposure on impaired semen quality.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Ácidos Ftálicos/metabolismo , Análise do Sêmen , Sêmen/efeitos dos fármacos , Adulto , Animais , China , Poluentes Ambientais/toxicidade , Humanos , Masculino , Estresse Oxidativo , Ácidos Ftálicos/toxicidade , Reprodução , Contagem de Espermatozoides
18.
Br J Nutr ; 122(3): 343-351, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31337445

RESUMO

Evaluation of Cr, Mn, Fe, Zn and Se in humans is challenged by the potentially high within-individual variability of these elements in biological specimens, which are poorly characterised. This study aimed to evaluate their within-day, between-day and between-month variability in spot samples, first-morning voids and 24-h collections. A total of 529 spot urine samples (including eighty-eight first-morning voids and 24-h collections) were collected from eleven Chinese adult men on days 0, 1, 2, 3, 4, 30, 60 and 90 and analysed for these five elements using inductively coupled plasma-MS. Intraclass correlation coefficients (ICC) were utilised to characterise the reproducibility, and their sensitivity and specificity were analysed to assess how well a single measurement classified individuals' 3-month average exposures. Serial measurements of Zn in spot samples exhibited fair to good reproducibility (creatinine-adjusted ICC = 0·47) over five consecutive days, which became poor when the samples were gathered months apart (creatinine-adjusted ICC = 0·33). The reproducibility of Cr, Mn, Fe and Se in spot samples was poor over periods ranging from days to months (creatinine-adjusted ICC = 0·01-0·12). Two spot samples were sufficient for classifying 60 % of the men who truly had the highest (top 33 %) 3-month average Zn concentrations; for Cr, Mn, Fe and Se, however, at least three specimens were required to achieve similar sensitivities. In conclusion, urinary Cr, Mn, Fe, Zn and Se concentrations showed a strong within-individual variability, and a single measurement is not enough to efficiently characterise individuals' long-term exposures.


Assuntos
Cromo/urina , Ferro/urina , Manganês/urina , Selênio/urina , Zinco/urina , Adulto , Biomarcadores/urina , China , Creatinina/urina , Exposição Ambiental/análise , Humanos , Masculino , Análise de Regressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Urinálise , Adulto Jovem
19.
J Neurogenet ; 33(2): 52-63, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30939963

RESUMO

Several large or mid-scale collections of Drosophila enhancer traps have been recently created to allow for genetic swapping of GAL4 coding sequences to versatile transcription activators or suppressors such as LexA, QF, split-GAL4 (GAL4-AD and GAL4-DBD), GAL80 and QS. Yet a systematic analysis of the feasibility and reproducibility of these tools is lacking. Here we focused on InSITE GAL4 drivers that specifically label different subpopulations of olfactory neurons, particularly local interneurons (LNs), and genetically swapped the GAL4 domain for LexA, GAL80 or QF at the same locus. We found that the major utility-limiting factor for these genetic swaps is that many do not fully reproduce the original GAL4 expression patterns. Different donors exhibit distinct efficacies for reproducing original GAL4 expression patterns. The successfully swapped lines reported here will serve as valuable reagents and expand the genetic toolkits of Drosophila olfactory circuit research.


Assuntos
Animais Geneticamente Modificados/genética , Proteínas de Drosophila/genética , Técnicas Genéticas , Fatores de Transcrição/genética , Animais , Drosophila , Feminino , Masculino
20.
Environ Res ; 172: 665-674, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30878738

RESUMO

Blood trihalomethanes (THMs) and urinary haloacetic acids (HAAs) are the leading candidate biomarkers for disinfection byproduct (DBP) exposure. However, no studies have assessed the exposure profiles, temporal variability, and potential predictors of these biomarkers during pregnancy. Here we collected blood (n = 4304) and urine samples (n = 4165) from 1760 Chinese pregnant women during early, mid-, and late pregnancy, which were separately analyzed for 4 THMs and 2 HAAs. We calculated the intraclass correlation coefficients (ICCs) to assess the variability of these biomarkers and estimated their correlations with sociodemographic, water-use behavioral, dietary and sample collection factors using mixed models. The median concentrations of TCM, BDCM, Br-THMs [sum of BDCM, dibromochloromethane (DBCM), bromoform (TBM)], total THMs (TTHMs, sum of TCM and Br-THMs), DCAA and TCAA in the water distribution system were 4.2 µg/L, 1.7 µg/L, 2.9 µg/L, 7.1 µg/L, 3.4 µg/L and 8.2 µg/L, respectively. Chloroform (TCM), bromodichloromethane (BDCM), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were detected in > 75% of the biospecimens. Repeated measurements of blood TCM, BDCM, Br-THMs and TTHMs and urinary DCAA and TCAA uniformly exhibited high variability (ICCs = 0.01-0.13); the use of a single measurement to classify gestational average exposure resulted in a high degree of exposure misclassification. The sampling season was a strong predictor of all analyzed DBPs. Additionally, we detected a positive association of blood TCM and BDCM with household income, urinary DCAA with age, and urinary TCAA with tap water usage, education level and amount of tap water consumed. Inverse associations were found between blood BDCM and vegetable consumption, and between blood Br-THM and TTHM and time interval since the last bathing/showering. Afternoon samples had lower DCAA concentrations than did early morning samples. Our results indicate that blood THM and urinary HAA concentrations vary greatly over the course of pregnancy and are affected by sampling season, time of day of blood/urine collection, sociodemographic factors, recent water-use activities and dietary intake.


Assuntos
Trialometanos , Poluentes Químicos da Água , Biomarcadores/sangue , Biomarcadores/urina , China , Ácido Dicloroacético/urina , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Gravidez , Ácido Tricloroacético/urina , Trialometanos/sangue , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/urina
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