Manipulating Ferroelectric Polarization and Spin Polarization of 2D CuInP2S6 Crystals for Photocatalytic CO2 Reduction.

Manipulating electronic polarizations such as ferroelectric or spin polarizations has recently emerged as an effective strategy for enhancing the efficiency of photocatalytic reactions. This study demonstrates the control of electronic polarizations modulated by ferroelectric and magnetic approaches within a two-dimensional (2D) layered crystal of copper indium thiophosphate (CuInP2S6) to boost the photocatalytic reduction of CO2. We investigate the substantial influence of ferroelectric polarization on the photocatalytic CO2 reduction efficiency, utilizing the ferroelectric-paraelectric phase transition and polarization alignment through electrical poling. Additionally, we explore enhancing the CO2 reduction efficiency by harnessing spin electrons through the synergistic introduction of sulfur vacancies and applying a magnetic field. Several advanced characterization techniques, including piezoresponse force microscopy, ultrafast pump-probe spectroscopy, in situ X-ray absorption spectroscopy, and in situ diffuse reflectance infrared Fourier transformed spectroscopy, are performed to unveil the underlying mechanism of the enhanced photocatalytic CO2 reduction. These findings pave the way for manipulating electronic polarizations regulated through ferroelectric or magnetic modulations in 2D layered materials to advance the efficiency of photocatalytic CO2 reduction.

Gestational Exposure to PM2.5 and Specific Constituents, Meconium Metabolites, and Neonatal Neurobehavioral Development: A Cohort Study.

Exposure to fine particulate matter (PM2.5) during pregnancy has been inversely associated with neonatal neurological development. However, the associations of exposure to specific PM2.5 constituents with neonatal neurological development remain unclear. We investigated these associations and examined the mediating role of meconium metabolites in a Chinese birth cohort consisting of 294 mother-infant pairs. Our results revealed that exposure to PM2.5 and its specific constituents (i.e., organic matter, black carbon, sulfate, nitrate, and ammonium) in the second trimester, but not in the first or third trimester, was inversely associated with the total neonatal behavioral neurological assessment (NBNA) scores. The PM2.5 constituent mixture in the second trimester was also inversely associated with NBNA scores, and sulfate was identified as the largest contributor. Furthermore, meconium metabolome analysis identified four metabolites, namely, threonine, lysine, leucine, and saccharopine, that were associated with both PM2.5 constituents and NBNA scores. Threonine was identified as an important mediator, accounting for a considerable proportion (14.53-15.33%) of the observed inverse associations. Our findings suggest that maternal exposure to PM2.5 and specific constituents may adversely affect neonatal behavioral development, in which meconium metabolites may play a mediating role.

Association of urinary and seminal plasma vanadium concentrations with semen quality: A repeated-measures study of 1135 healthy men.

Although animal studies have shown the reproductive toxicity of vanadium, less is known about its effects on semen quality in humans. Among 1135 healthy men who were screened as potential semen donors, we investigated the relationships of semen quality with urinary and seminal plasma vanadium levels via inductively coupled plasma-mass spectrometry (ICP-MS). Spearman rank correlation tests and linear regression models were used to assess the correlations between average urinary and within-individual pooled seminal plasma vanadium concentrations (n = 1135). We utilized linear mixed-effects models to evaluate the associations of urinary and seminal plasma vanadium levels (n = 1135) with repeated sperm quality parameters (n = 5576). Seminal plasma vanadium concentrations were not significantly correlated with urinary vanadium concentrations (r = 0.03). After adjusting for possible confounders, we observed inverse relationships of within-individual pooled seminal plasma vanadium levels with total count, semen volume, and sperm concentration (all P values for trend < 0.05). Specifically, subjects in the highest (vs. lowest) tertile of seminal plasma vanadium concentrations had - 11.3% (-16.4%, -5.9%), - 11.1% (-19.1%, -2.4%), and - 20.9% (-29.0%, -11.8%) lower sperm volume, concentration, and total count, respectively; moreover, urinary vanadium levels appeared to be negatively associated with sperm motility. These relationships showed monotonically decreasing dose-response patterns in the restricted cubic spline analyses. Our results demonstrated a poor correlation between urinary and seminal plasma levels of vanadium, and elevated vanadium concentrations in urine and seminal plasma may be adversely related to male semen quality.

Enhancing the Photocatalytic Degradation Efficiency of Dyes of Copper-Based Metal-Organic Frameworks through a Dimension-Induced Structural Strategy.

Photocatalytic degradation of pollutants is an effective environment purification strategy. Metal-organic frameworks (MOFs) have attracted extensive attention in the field of photocatalysis owing to their structural diversity, uniform cavity, and large specific surface area. However, poor electrical conductivity, light absorption, and water stability restrict their development. The tailorable structure of MOFs may effectively overcome these limitations. Herein, three Cu-based MOFs (complexes 1-3) with one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) structures, respectively, were successfully prepared by introducing different uncoordinated ligands and adjusting the ligand/metal salt ratio. Among them, complex 1 with a 1D chain was constructed as a typical J-type aggregation by π-π stacking interactions between adjacent naphthalene rings. This intermolecular aggregation mode enhances strong exciton coupling between conjugated rings, reduces the transition energy, expands the intrinsic light absorption edge, and provides a channel for electron transport, thus improving the charge-separation efficiency. As expected, complex 1 with a 1D chain structure exhibited excellent Fenton-like catalytic activity. The apparent reaction rates were 3.2 and 2.0 times higher than those of 2D and 3D MOFs, respectively.

Direct White-Light Emitting From a Single Metal-Organic Framework with Dual Phosphorescence Peaks.

Single component white-light-emitting (SCWLE) materials are extremely desired in the field of solid-state lighting. However, pure-phosphorescent SCWLE has rarely been reported. Herein, one halogen-bonding-containing MOF [Cd(5-BIPA)(phen)] (1) has been synthesized, which shows efficient white-light emission originating from dual phosphorescence bands with different wavelengths and lifetimes. The fabrication of a phosphor-converted white-light-emitting diode device driven by pulsing current enables this MOF to be a promising phosphor.

Fast photocatalytic degradation of rhodamine B using indium-porphyrin based cationic MOF under visible light irradiation.

A broad light-harvesting range and efficient charge separation are two main ways to enhance the visible photocatalytic performance of semiconductors. Herein, an ionic porphyrin MOF [In(TPyP)]·(NO3) (1) (TPyP = 5,10,15,20-tetrakis(4-pyridyl)-21H,23H-porphyrin) was synthesized via in situ metalation. The orderly arranged porphyrin photosensitizer and the internal electric field between the MOF host and NO3- guests enable effective visible light response and electron-hole separation. Consequently, the as-synthesized MOF shows efficient photocatalytic degradation of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) organic pollutants. It can degrade 99.07% of RhB within only 20 minutes under visible light irradiation (λ > 420 nm) with a high chemical reaction rate constant of 0.2400 min-1. The photocatalytic activity of the title MOF is more efficient than those of other reported MOFs, COFs and even inorganic semiconductors. The reusability, energy level, band gap, charge distribution and main degradation mechanisms of the photocatalyst were well studied.

Blood trihalomethane concentrations in relation to sperm mitochondrial DNA copy number and telomere length among 958 healthy men.

BACKGROUND: In animal and human studies, exposure to trihalomethanes (THMs) has been associated with reduced semen quality. However, the underlying mechanisms remain poorly understood. OBJECTIVE: To investigate the associations of blood THM concentrations with sperm mitochondrial DNA copy number (mtDNAcn) and telomere length (TL) among healthy men. METHODS: We recruited 958 men who volunteered as potential sperm donors. A single blood sample was collected from each participant at recruitment and measured for chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM) concentrations. Within a 90-day follow-up, the last semen sample provided by each participant was quantified for sperm mtDNAcn and TL. We used multivariable linear regression models to assess the associations between blood THM concentrations and sperm mtDNAcn and TL. We also performed stratified analyses according to the time intervals between baseline blood THM determinations and semen collection (i.e., 0-9, 10-14, 15-69, or >69 days) to explore potential windows of susceptibility. RESULTS: After adjusting for potential confounders, we found inverse associations between quartiles (or categories) of blood TBM, brominated THM (Br-THM, the sum of BDCM, DBCM, and TBM), and total THM (TTHM, the sum of all four THMs) concentrations and sperm mtDNAcn (all P for trend≤0.03). Besides, we found inverse associations between quartiles of blood TCM, Br-THM, chlorinated THM (Cl-THM, the sum of TCM, BDCM, and DBCM), and TTHM concentrations and sperm TL (all P for trend<0.10). Stratified analyses showed stronger associations between Br-THM concentrations and sperm mtDNAcn determined 15-69 days since baseline exposure determinations, and between blood TCM and TTHM concentrations and sperm TL determined >69 days since baseline exposure determinations. CONCLUSION: Exposure to THMs may be associated with sperm mitochondrial and telomeric dysfunction.

Sperm mitochondrial DNA copy number mediates the association between seminal plasma selenium concentrations and semen quality among healthy men.

Selenium (Se) is essential for successful male reproduction. However, the association of Se status with human semen quality remains controversial and the underlying mechanisms are poorly understood. We measured seminal plasma Se concentrations, sperm mitochondrial DNA copy number (mtDNAcn), and sperm quality parameters among healthy Chinese men screened as potential sperm donors. Linear mixed-effects models were used to investigate the associations of within-subject pooled seminal plasma Se concentrations (n = 1159) with repeated sperm quality parameters (n = 5617); mediation analyses were applied to evaluate the mediating role of sperm mtDNAcn (n = 989). Seminal plasma Se concentrations were positively associated with sperm concentration and total count (both P for trend < 0.001). In adjusted models, men in the top vs. bottom quartiles of seminal plasma Se concentrations had 70.1 % (95 % CI: 53.3 %, 88.9 %) and 59.1 % (95 % CI: 40.5 %, 80.2 %) higher sperm concentration and total count, respectively. Meanwhile, we observed inverse associations between seminal plasma Se concentrations and sperm mtDNAcn, and between sperm mtDNAcn and sperm motility, concentration, and total count (all P for trend < 0.05). Mediation analyses suggested that sperm mtDNAcn mediated 19.7 % (95 % CI: 15.9 %, 25.3 %) and 23.1 % (95 % CI: 17.4 %, 33.4 %) of the associations between seminal plasma Se concentrations and sperm concentration and total count, respectively. Our findings suggest that Se is essential for male spermatogenesis, potentially by affecting sperm mtDNAcn.

Associations of Urinary Trichloroacetic Acid Concentrations with Spermatozoa Apoptosis and DNA Damage in a Chinese Population.

Exposure to trichloroacetic acid (TCAA) has been associated with impaired semen quality; however, its association with spermatozoa apoptosis and DNA damage remains unclear. We, therefore, collected single semen and repeated urine samples from male partners of couples attending a reproductive center, which were measured for spermatozoa apoptosis and DNA damage parameters and TCAA concentrations, respectively. Multivariable linear regression models were used to explore the associations between urinary TCAA concentrations and spermatozoa apoptosis (n = 462) and DNA damage parameters (n = 512). After adjusting for potential confounders, positive dose-response relationships were found between urinary TCAA concentrations and percentage of tail DNA (tail%) and tail-distributed moment (TDM) (both p for trend <0.10). Compared with men in the lowest tertile of urinary TCAA concentrations, men in the highest tertile had a greater tail% and TDM of 6.2% (95% CI: 0.7, 12.2%) and 8.9% (95% CI: -1.9, 20.5%), respectively. Urinary TCAA concentrations were unrelated to spermatozoa apoptosis parameters in a dose-response manner. However, urinary TCAA concentrations were positively associated with the percentage of Annexin V+/PI- spermatozoa (apoptotic cells), when urinary TCAA concentrations were modeled as continuous variables. Our results suggest that exposure to TCAA at concentrations in real-world scenarios may be associated with spermatozoa apoptosis and DNA damage.

Sperm mitochondrial DNA copy number in relation to semen quality: A cross-sectional study of 1164 potential sperm donors.

OBJECTIVE: To investigate the association between mitochondrial DNA copy number (mtDNAcn) and semen quality. DESIGN: A cross-sectional study. SETTING: Hubei Province Human Sperm Bank of China (from April 2017 to July 2018). POPULATION: A total of 1164 healthy male sperm donors with 5739 specimens. MAIN OUTCOME MEASURES: Real-time quantitative polymerase chain reaction (RT-PCR) was used to measure sperm mtDNAcn. We also determined semen volume, concentration and motility parameters (progressive motility, nonprogressive motility and immotility). METHODS: Mixed-effect models and general linear models were uses. RESULTS: After adjusting for relevant confounding factors, mixed-effect models revealed diminished sperm motility (progressive and total), concentration, and total count across the quartiles of mtDNAcn (all P < 0.05). Compared with men in the lowest quartile, men in the highest quartile of mtDNAcn had lower progressive sperm motility, total motility, concentration and total count of -8.9% (95% CI -12.7% to -5.0%), -8.0% (95% CI -11.6% to -4.4%), -42.8% (95% CI -47.7% to -37.4%), and - 44.3% (95% CI -50.1% to -37.7%), respectively. These inverse dose-response relationships were further confirmed in the cubic spline models, where mtDNAcn was modelled as a continuous variable. CONCLUSIONS: We found that mtDNAcn was inversely associated with semen quality in a dose-dependent manner. Our results provide novel clues that sperm mtDNAcn may serve as a useful predictor of human semen characteristics. TWEETABLE ABSTRACT: Sperm mitochondrial DNA copy number was markedly associated with diminished sperm motility (progressive and total), concentration and total count.

Prenatal Exposure to Disinfection Byproducts and Intrauterine Growth in a Chinese Cohort.

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.

Physical activity and sedentary time in relation to semen quality in healthy men screened as potential sperm donors.

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.

Differential efficacy of genetically swapping GAL4.

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.

Reproducibility of essential elements chromium, manganese, iron, zinc and selenium in spot samples, first-morning voids and 24-h collections from healthy adult men.

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.

Urinary biomarker of late pregnancy exposure to drinking water disinfection by-products and ultrasound measures of fetal growth in Wuhan, China.

BACKGROUND: Disinfection by-products (DBPs) have been shown to be reproductive and developmental toxicity. However, few studies examine the effect of prenatal exposure to DBPs on fetal growth via ultrasound measures. OBJECTIVE: To investigate the associations between maternal exposure to DBPs during late pregnancy and ultrasound measures of fetal growth. METHODS: We included 332 pregnant women who presented to a hospital to wait for delivery in Wuhan, China. Ultrasound parameters of fetal growth including femur length (FL), head circumference (HC), abdominal circumference (AC) and biparietal diameter (BPD) were assessed. We measured maternal TCAA concentrations in first morning urine collected from late pregnancy as a biomarker of in utero DBP exposure levels. Multivariable linear regression models were used to examine the associations between maternal urinary TCAA concentrations during late pregnancy and ultrasound parameters of fetal growth. RESULTS: We found that elevated maternal creatinine (Cr)-adjusted urinary TCAA levels had negative associations with BPD, HC and FL in boys but not in girls (P interaction = 0.04, 0.05 and 0.08, respectively). Male fetal BPD, HC and FL had decreases of 0.21 cm (95% CI: -0.35, -0.07; P for trend = 0.003), 0.46 cm (95% CI: -0.81, -0.10; P for trend = 0.01) and 0.17 cm (95% CI: -0.30, -0.04; P for trend = 0.01) for the highest vs. lowest tertile of Cr-adjusted urinary TCAA, respectively. These negative associations persisted for maternal Cr-adjusted urinary TCAA concentrations modeled as continuous variables. CONCLUSION: The results from our study suggest that maternal exposure to TCAA during late pregnancy may have adverse effects on male fetal growth.

Mediation of the relationship between phthalate exposure and semen quality by oxidative stress among 1034 reproductive-aged Chinese men.

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.

Profiles, variability and predictors of concentrations of blood trihalomethanes and urinary haloacetic acids along pregnancy among 1760 Chinese women.

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.

Predictors and correlations of phthalate metabolite concentrations in urine and seminal plasma among reproductive-aged men.

BACKGROUND: Certain phthalates are suspected to be endocrine disruptors that are adversely associated with male reproductive health. However, the predictors and correlations of phthalate metabolite concentrations in urine and seminal plasma among reproductive-aged men have not been thoroughly studied. OBJECTIVE: To investigate the predictors and correlations of phthalate metabolite concentrations in urine and seminal plasma among adult Chinese males. METHOD: We measured mono-n-butyl phthalate (MBP), monobenzyl phthalate (MBzP), monomethyl phthalate (MMP), monoethyl phthalate (MEP), mono-n-octyl phthalate (MOP), mono(2-ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) concentrations in seminal plasma and repeated spot-urine samples from 687 men who visited a reproductive center. Mixed-effect models were used to examine the associations of sociodemographic, lifestyle and medical factors with urinary metabolite concentrations. Linear regression models were used to identify predictors of metabolite concentrations in seminal plasma and correlations between metabolite concentrations in spot urine samples and seminal plasma. RESULTS: Measurements taken from spot urine samples poorly predicted same-day seminal plasma concentrations (all R2<0.10). Inverse associations were observed between education level and urinary MBP and MEOHP and between household income and urinary MMP; receiving intravenous infusion therapy was associated with increased urinary MBP, MEHHP and MEOHP, use of facial cleanser/cream was associated with increased MEP, and smoking was associated with increased MEHP. The predictors of metabolite concentrations in seminal plasma differed from those in urine, except for the association of intravenous infusion therapy with MBP. BMI was associated with increased seminal plasma MBP, MEHP and MEOHP, smoking was associated with increased MEP, and contact with plastics was associated with increased MEOHP. CONCLUSIONS: Phthalate metabolite concentrations in adult men varied in accordance with sociodemographic variables, lifestyle factors and intravenous therapy. Measures of metabolite levels in urine may not directly reflect the exposure status of the male reproductive system.

Urinary Polycyclic Aromatic Hydrocarbon Metabolites and Human Semen Quality in China.

Toxicological studies have demonstrated that polycyclic aromatic hydrocarbons (PAHs) exposure impairs male reproductive health. However, the epidemiological evidence is limited and discordant. Our goal was to investigate the relationship between PAH exposures and human semen quality. We analyzed 12 urinary metabolites of PAHs from 933 men who sought semen quality analysis in an infertility clinic in Wuhan, China. Associations with semen quality were assessed using a multivariable linear regression. Restricted cubic splines were used to explore the dose-response relationships between urinary metabolites of PAHs and semen quality. We observed inverse associations between urinary 1-hydroxynaphthalene (1-OHNa) and sperm count, sperm concentration, and percentage of normal morphology (all p for trends <0.05) as well as between urinary ∑OHNa (sum of 1-OHNa and 2-OHNa) and sperm concentration (p for trend =0.04). Additionally, we found inverse associations between urinary 9-hydroxyphenanthrene (9-OHPh) and semen volume and sperm straight-line velocity (both p for trends <0.05) as well as between urinary ∑OHPh (sum of 1-, 2-, 3-, 4-, and 9-OHPh) and sperm count (p for trend =0.04). These dose-response relationships were further confirmed in the curves of the restricted cubic splines. Our data suggest that exposure to naphthalene and phenanthrene is related to decreased semen quality. Our results contribute to the growing body of evidence regarding the widespread exposure to PAHs and the detriment to male reproductive function.

Laparoscopic liver resection under hemihepatic vascular inflow occlusion using the lowering of hilar plate approach.

BACKGROUND: With advances in technology, laparoscopic liver resection is widely accepted. Laparoscopic liver resection under hemihepatic vascular inflow occlusion has advantages over the conventional total hepatic inflow occlusion using the Pringle's maneuver, especially in patients with cirrhosis. METHOD: From November 2011 to August 2012, eight consecutive patients underwent laparoscopic liver resection under hemihepatic vascular inflow occlusion using the lowering of hilar plate approach with biliary bougie assistance. RESULTS: The types of liver resection included right hepatectomy (n=1), right posterior sectionectomy (n=1), left hepatectomy and common bile duct exploration (n=1), segment 4b resection (n=1), left lateral sectionectomy (n=2), and wedge resection (n=2). Four patients underwent right and 4 left hemihepatic vascular inflow occlusion. Four patients had cirrhosis. The mean operation time was 176.3 minutes. The mean time taken to achieve hemihepatic vascular inflow occlusion was 24.3 minutes. The mean duration of vascular inflow occlusion was 54.5 minutes. The mean intraoperative blood loss was 361 mL. No patient required blood transfusion. Postoperatively, one patient developed bile leak which healed with conservative treatment. No postoperative liver failure and mortality occurred. The mean hospital stay of the patients was 7 days. CONCLUSION: Our technique of hemihepatic vascular inflow vascular occlusion using the lowering of hilar plate approach was safe, and it improved laparoscopic liver resection by minimizing blood loss during liver parenchymal transection.