Trimester-specific associations of maternal exposure to disinfection by-products, oxidative stress, and neonatal neurobehavioral development.

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.

Corrigendum to "Comparative analysis of Phytophthora genomes reveals oomycete pathogenesis in crops" [Heliyon 7 (2) (February 2021) e06317].

[This corrects the article DOI: 10.1016/j.heliyon.2021.e06317.].

Comparative analysis of Phytophthora genomes reveals oomycete pathogenesis in crops.

The oomycete genus Phytophthora includes devastating plant pathogens that are found in almost all ecosystems. We sequenced the genomes of two quarantined Phytophthora species-P. fragariae and P. rubi. Comparing these Phytophthora species and related genera allowed reconstruction of the phylogenetic relationships within the genus Phytophthora and revealed Phytophthora genomic features associated with infection and pathogenicity. We found that several hundred Phytophthora genes are putatively inherited from red algae, but Phytophthora does not have vestigial plastids originating from phototrophs. The horizontally-transferred Phytophthora genes are abundant transposons that "transmit" exogenous gene to Phytophthora species thus bring about the gene recombination possibility. Several expansion events of Phytophthora gene families associated with cell wall biogenesis can be used as mutational targets to elucidate gene function in pathogenic interactions with host plants. This work enhanced the understanding of Phytophthora evolution and will also be helpful for the design of phytopathological control strategies.

Blood and urinary biomarkers of prenatal exposure to disinfection byproducts and oxidative stress: A repeated measurement analysis.

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.

First-trimester blood concentrations of drinking water trihalomethanes and neonatal neurobehavioral development in a Chinese birth cohort.

Toxicological evidence indicates that exposure to drinking water trihalomethanes (THMs) can impair neural development. However, no epidemiologic study to date has evaluated the relation of trihalomethanes exposure with neonatal neurobehavioral development. Here we aimed to evaluate if prenatal exposure to THMs during early pregnancy is associated with neonatal neurobehavioral development in 451 Chinese mother-child pairs. First trimester blood THMs [chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM)] were determined by solid phase micro-extraction gas chramatography. Neonatal neurobehavioral development was assessed using neonatal behavioral neurological assessment (NBNA) on the third day after birth. Multivariable linear regression models and restricted cubic spline models were constructed to evaluate the associations between blood THMs and neonatal neurological development scores. Blood concentrations of BDCM, whether modeled as continuous or categorical variables, were inversely associated with total NBNA score of newborns based on the multivariable linear regression. The association was further confirmed in the cubic spline model, and a linear dose-response relationship was observed. Stratified analysis showed that the inverse association between blood BDCM and total NBNA score was more evident in male infants than females. Our findings suggest that exposure to THMs during early pregnancy may be associated with impaired neonatal neurobehavioral development.

Blood Biomarkers of Late Pregnancy Exposure to Trihalomethanes in Drinking Water and Fetal Growth Measures and Gestational Age in a Chinese Cohort.

BACKGROUND: Previous studies have suggested that elevated exposure to disinfection by-products (DBPs) in drinking water during gestation may result in adverse birth outcomes. However, the findings of these studies remain inconclusive. OBJECTIVE: The purpose of our study was to examine the association between blood biomarkers of late pregnancy exposure to trihalomethanes (THMs) in drinking water and fetal growth and gestational age. METHODS: We recruited 1,184 pregnant women between 2011 and 2013 in Wuhan and Xiaogan City, Hubei, China. Maternal blood THM concentrations, including chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM), were measured as exposure biomarkers during late pregnancy. We estimated associations with gestational age and fetal growth indicators [birth weight, birth length, and small for gestational age (SGA)]. RESULTS: Total THMs (TTHMs; sum of TCM, BDCM, DBCM, and TBM) were associated with lower mean birth weight (-60.9 g; 95% CI: -116.2, -5.6 for the highest vs. lowest tertile; p for trend = 0.03), and BDCM and DBCM exposures were associated with smaller birth length (e.g., -0.20 cm; 95% CI: -0.37, -0.04 for the highest vs. lowest tertile of DBCM; p for trend = 0.02). SGA was increased in association with the second and third tertiles of TTHMs (OR = 2.91; 95% CI: 1.32, 6.42 and OR = 2.25; 95% CI: 1.01, 5.03; p for trend = 0.08). CONCLUSIONS: Our results suggested that elevated maternal THM exposure may adversely affect fetal growth. CITATION: Cao WC, Zeng Q, Luo Y, Chen HX, Miao DY, Li L, Cheng YH, Li M, Wang F, You L, Wang YX, Yang P, Lu WQ. 2016. Blood biomarkers of late pregnancy exposure to trihalomethanes in drinking water and fetal growth measures and gestational age in a Chinese cohort. Environ Health Perspect 124:536-541; http://dx.doi.org/10.1289/ehp.1409234.

Generation of marker-free transgenic plants concurrently resistant to a DNA geminivirus and a RNA tospovirus.

Global threats of ssDNA geminivirus and ss(-)RNA tospovirus on crops necessitate the development of transgenic resistance. Here, we constructed a two-T DNA vector carrying a hairpin of the intergenic region (IGR) of Ageratum yellow vein virus (AYVV), residing in an intron inserted in an untranslatable nucleocapsid protein (NP) fragment of Melon yellow spot virus (MYSV). Transgenic tobacco lines highly resistant to AYVV and MYSV were generated. Accumulation of 24-nt siRNA, higher methylation levels on the IGR promoters of the transgene, and suppression of IGR promoter activity of invading AYVV indicate that AYVV resistance is mediated by transcriptional gene silencing. Lack of NP transcript and accumulation of corresponding siRNAs indicate that MYSV resistance is mediated through post-transcriptional gene silencing. Marker-free progenies with concurrent resistance to both AYVV and MYSV, stably inherited as dominant nuclear traits, were obtained. Hence, we provide a novel way for concurrent control of noxious DNA and RNA viruses with less biosafety concerns.

Antidepressant-Like Activity of the Ethanolic Extract from Uncaria lanosa Wallich var. appendiculata Ridsd in the Forced Swimming Test and in the Tail Suspension Test in Mice.

This study investigated the antidepressant activity of ethanolic extract of U. lanosa Wallich var. appendiculata Ridsd (UL(EtOH)) for two-weeks administrations by using FST and TST on mice. In order to understand the probable mechanism of antidepressant-like activity of UL(EtOH) in FST and TST, the researchers measured the levels of monoamines and monoamine oxidase activities in mice brain, and combined the antidepressant drugs (fluoxetine, imipramine, maprotiline, clorgyline, bupropion and ketanserin). Lastly, the researchers analyzed the content of RHY in the UL(EtOH). The results showed that UL(EtOH) exhibited antidepressant-like activity in FST and TST in mice. UL(EtOH) increased the levels of 5-HT and 5-HIAA in cortex, striatum, hippocampus, and hypothalamus, the levels of NE and MHPG in cortex and hippocampus, the level of NE in striatum, and the level of DOPAC in striatum. Two-week injection of IMI, CLO, FLU and KET enhanced the antidepressant-like activity of UL(EtOH). UL(EtOH) inhibited the activity of MAO-A. The amount of RHY in UL(EtOH) was 17.12 mg/g extract. Our findings support the view that UL(EtOH) exerts antidepressant-like activity. The antidepressant-like mechanism of UL(EtOH) may be related to the increase in monoamines levels in the hippocampus, cortex, striatum, and hypothalamus of mice.

[PCR detection of transgenic elements in feed raw material].

Based on the heterogeneous genes usually used in transgenic crops, the PCR technique was performed with primers derived from CaMV 35S promoter (35S-promoter,originated from cauliflower mosaic virus), NOS terminator (nopaline synthase-terminator,derived from Agrobacterium tumefaciens), EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) gene, and CryIA(b) (delta-endotoxin,evolved from Bacillus thuringiensis subsp. kurstaki) gene to detect transgenic agents from feed raw materials of soybean dregs and corn gluten meal, respectively. Endogenous corn Zein (a protein extracted from corn gluten) gene, soybean Lectin (chitin-binding protein) gene and negative, positive control were applied for avoiding false results. The method established here has been successfully applied in detecting transgenic elements in imported feed raw material.