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1.
Environ Sci Technol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629313

RESUMO

Plant guttation is an important source of water/nutrients for many beneficial insects, while the presence of pesticides in guttation has been considered as a new exposure route for nontarget insects. This study aimed to elucidate how 15 diverse pesticides are translocated from growth media to guttation by maize plants through a hydroponic experiment. All pesticides were effectively translocated from the growth solution to maize guttation and reached a steady state within 5 days. The strong positive correlation (R2 = 0.43-0.84) between the concentrations of pesticides in guttation and in xylem sap demonstrated that xylem sap was a major source of pesticides in guttation. The relationship between the bioaccumulation of pesticides in guttation (BCFguttation) and the chemical Kow was split into two distinct patterns: for pesticides with log Kow > 3, we identified a good negative linear correlation between log BCFguttation and log Kow (R2 = 0.71); however, for pesticides with log Kow < 3, all data fall close to a horizontal line of BCFguttation ≅ 1, indicating that hydrophilic pesticides can easily pass through the plants from rhizosphere solution to leaf guttation and reach saturation status. Besides, after feeding with pesticide-contaminated guttation, the mortality of honeybees was significantly impacted, even at very low levels (e.g., ∑600 µg/L with a mortality of 93%). Our results provide essential information for predicting the contamination of plant guttation with pesticides and associated ecological risks.

2.
Sci Total Environ ; 925: 171670, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38485020

RESUMO

Many studies investigate the plant uptake and metabolism of xenobiotics by hydroponic experiments, however, plants grown in different conditions (hydroponic vs. soil) may result in different behaviors. To explore the potential differences, a comparative study on the uptake, translocation and metabolism of the fungicide phenamacril in crops (wheat/rice) under hydroponic and soil cultivation conditions was conducted. During 7-14 days of exposure, the translocation factors (TFs) of phenamacril were greatly overestimated in hydroponic-wheat (3.6-5.2) than those in soil-wheat systems (1.1-2.0), with up to 3.3 times of difference between the two cultivation systems, implying it should be cautious to extrapolate the results obtained from hydroponic to field conditions. M-144 was formed in soil pore water (19.1-29.9 µg/L) in soil-wheat systems but not in the hydroponic solution in hydroponics; M-232 was only formed in wheat shoots (89.7-103.0 µg/kg) under soil cultivation conditions, however, it was detected in hydroponic solution (20.1-21.2 µg/L), wheat roots (146.8-166.0 µg/kg), and shoots (239.2-348.1 µg/kg) under hydroponic conditions. The root concentration factors (RCFs) and TFs of phenamacril in rice were up to 2.4 and 3.6 times higher than that in wheat for 28 days of the hydroponic exposure, respectively. These results highlighted that cultivation conditions and plant species could influence the fate of pesticides in crops, which should be considered to better assess the potential accumulation and transformation of pesticides in crops.


Assuntos
Cianoacrilatos , Oryza , Praguicidas , Poluentes do Solo , Hidroponia , Solo , Produtos Agrícolas/metabolismo , Praguicidas/metabolismo , Triticum/metabolismo , Oryza/metabolismo , Raízes de Plantas/metabolismo , Poluentes do Solo/análise
3.
Environ Sci Technol ; 58(3): 1680-1689, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38173396

RESUMO

Pesticides are frequently sprayed in greenhouses to ensure crop yields, where airborne particulate matter (PM) may serve as a carrier in depositing and transporting pesticides. However, little is known about the occurrence and fate of PM-borne pesticides in greenhouses. Herein, we examined the distribution, dissipation, and transformation of six commonly used pesticides (imidacloprid, acetamiprid, prochloraz, triadimefon, hexaconazole, and tebuconazole) in greenhouse PM (PM1, PM2.5, and PM10) after application as well as the associated human exposure risks via inhalation. During 35 days of experiment, the six pesticides were detected in all PM samples, and exhibited size- and time-dependent distribution characteristics, with the majority of them (>64.6%) accumulated in PM1. About 1.0-16.4% of initially measured pesticides in PM remained after 35 days, and a total of 12 major transformation products were elucidated, with six of them newly identified. The inhalation of PM could be an important route of human exposure to pesticides in the greenhouse, where the estimated average daily human inhalation dose (ADDinh) of the six individual pesticides was 2.1-1.2 × 104 pg/kg day-1 after application (1-35 days). Our findings highlight the occurrence of pesticides/transformation products in greenhouse PM, and their potential inhalation risks should be further concerned.


Assuntos
Poluentes Atmosféricos , Praguicidas , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , China
4.
Chemosphere ; 328: 138577, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37019393

RESUMO

Pesticide residues in grapes could be transferred to fermentation system during the wine-making process, which may interfere the normal proliferation of Saccharomyces cerevisiae and subsequently affect the safety and quality of wine products. However, the interaction between pesticides and Saccharomyces cerevisiae is still poorly understood. Herein, the fate, distribution and interaction effect with Saccharomyces cerevisiae of five commonly-used pesticides during the wine-making process were evaluated. The five pesticides exerted varied inhibition on the proliferation of Saccharomyces cerevisiae, and the order of inhibition intensity was difenoconazole > tebuconazole > pyraclostrobin > azoxystrobin > thiamethoxam. Compared with the other three pesticides, triazole fungicides difenoconazole and tebuconazole showed stronger inhibition and played a major role in binary exposure. The mode of action, lipophilicity and exposure concentration were important factors in the inhibition of pesticides. Saccharomyces cerevisiae had no obvious impacts on the degradation of target pesticides in the simulated fermentation experiment. However, the levels of target pesticides and their metabolite were significantly reduced during the wine-making process, with the processing factors ranged from 0.030 to 0.236 (or 0.032 to 0.257) during spontaneous (or inoculated) wine-making process. As a result, these pesticides were significantly enriched in the pomace and lees, and showed a positive correlation (R2 ≥ 0.536, n = 12, P < 0.05) between the hydrophobicity of pesticides and distribution coefficients in the solid-liquid distribution system. The findings provide important information for rational selection of pesticides on wine grapes and facilitate more accurate risk assessments of pesticides for grape processing products.


Assuntos
Fungicidas Industriais , Resíduos de Praguicidas , Praguicidas , Vitis , Vinho , Vinho/análise , Praguicidas/toxicidade , Praguicidas/metabolismo , Saccharomyces cerevisiae/metabolismo , Resíduos de Praguicidas/análise , Fungicidas Industriais/toxicidade , Fungicidas Industriais/metabolismo , Fermentação
5.
PLoS Med ; 20(3): e1004197, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36877740

RESUMO

BACKGROUND: LGBTQ+ community's higher susceptibility to worse mental health outcomes and more help-seeking barriers compared to the cis-heterosexual population. Despite the LGBTQ+ population facing higher mental health risks, there has been a dearth of research focusing on developing tailored interventions targeting them. This study aimed to assess the effectiveness of a digital multicomponent intervention in promoting help-seeking for mental health issues in LGBTQ+ young adults. METHODS AND FINDINGS: We recruited LGBTQ+ young adults aged between 18 and 29 who scored moderate or above on at least 1 dimension of the Depression Anxiety Stress Scale 21 and did not have help-seeking experiences in the past 12 months. Participants (n = 144) were stratified by gender assigned at birth (male/female) and randomly allocated (1:1 ratio) to the intervention or active control parallel condition by generating a random number table, so they were blinded to the intervention condition. All participants received online psychoeducational videos, online facilitator-led group discussions, and electronic brochures in December 2021 and January 2022, with the final follow-up in April 2022. The contents of the video, discussion, and brochure are help-seeking for the intervention group and general mental health knowledge for the control group. The primary outcomes were help-seeking intentions for emotional problems and suicidal ideation and attitudes toward seeking help from mental health professionals at the 1-month follow-up. The analysis was performed by including all participants based on their randomized group regardless of adherence to the protocol. A linear mixed model (LMM) was used for analysis. All models were adjusted for baseline scores. Chinese Clinical Trial Registry: ChiCTR2100053248. A total of 137 (95.1%) participants completed a 3-month follow-up, and 4 participants from the intervention condition and 3 from the control condition did not complete the final survey. Compared with the control group (n = 72), a significant improvement was found in help-seeking intentions for suicidal ideation in the intervention group (n = 70) at post-discussion (mean difference = 0.22, 95% CI [0.09, 0.36], p = 0.005), 1-month (mean difference = 0.19, 95% CI [0.06, 0.33], p = 0.018), and 3-month follow-ups (mean difference = 0.25, 95% CI [0.11, 0.38], p = 0.001). There was also a significant improvement in the intervention condition on the help-seeking intention for emotional problems at 1-month (mean difference = 0.17, 95% CI [0.05, 0.28], p = 0.013) and 3-month follow-ups (mean difference = 0.16, 95% CI [0.04, 0.27], p = 0.022) compared with the control group. Participants' depression and anxiety literacy and help-seeking encouragement related knowledge in intervention conditions showed significant improvements. There were no significant improvements in actual help-seeking behaviors, self-stigma toward seeking professional assistance, depression, and anxiety symptoms. No adverse events or side effects were observed. However, the follow-up time point was limited to 3 months which might not be long enough for drastic mindset and behavioral changes in help-seeking to occur. CONCLUSIONS: The current intervention was an effective approach in promoting help-seeking intentions, mental health literacy, and help-seeking encouragement-related knowledge. Its brief yet integrated intervention format could also be utilized in treating other imminent concerns confronted by LGBTQ+ young adults. TRIAL REGISTRATION: Chictr.org.cn, ChiCTR2100053248.


Assuntos
Saúde Mental , Suicídio , Recém-Nascido , Humanos , Masculino , Feminino , Adulto Jovem , Lactente , Pré-Escolar , Ideação Suicida , Ansiedade/terapia , Estigma Social
6.
Adv Mater ; 35(16): e2210895, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36757878

RESUMO

Epigenetic-alterations-mediated antigenicity reducing in leukemic blasts (LBs) is one of the critical mechanisms of immune escape and resistance to T-cell-based immunotherapy. Herein, a bimetallic metal-organic framework (MOF)-based biomimetic nanoplatform (termed as AFMMB) that consists of a DNA hypomethylating agent, a leukemia stem cell (LSC) membrane, and pro-autophagic peptide is fabricated. These AFMMB particles selectively target not only LBs but also LSCs due to the homing effect and immune compatibility of the LSC membrane, and induce autophagy by binding to the Golgi-apparatus-associated protein. The autophagy-triggered dissolution of AFMMB releases active components, resulting in the restoration of the stimulator of interferon genes pathway by inhibiting DNA methylation, upregulation of major histocompatibility complex class-I molecules, and induction of RNA-methylation-mediated decay of programmed cell death protein ligand transcripts. These dual epigenetic changes eventually enhance T-cell-mediated immune response due to increased antigenicity of leukemic cells. AFMMB also can suppress growth and metastases of solid tumor, which was suggestive of a pan-cancer effect. These findings demonstrate that AFMMB may serve as a promising new nanoplatform for dual epigenetic therapy against cancer and warrants clinical validation.


Assuntos
Leucemia Mieloide Aguda , Estruturas Metalorgânicas , Humanos , Estruturas Metalorgânicas/uso terapêutico , Metilação de DNA , RNA/metabolismo , Biomimética , Desmetilação do DNA , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia
7.
Food Chem ; 400: 134049, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36067689

RESUMO

Novel insecticide cyetpyrafen is frequently used in various crops, however, knowledge of its fate in crops and environments is largely unexplored. In this study, an effective method was firstly established for simultaneous determination of cyetpyrafen and its metabolites (M-309 and M-391) in 13 matrices (e.g., plants and soils) to explore their fate. Mean recoveries of the three compounds ranged from 73.1 % to 118.7 % with the relative standard deviations (RSDs) less than 17.9 %. Further, after 28 days of exposure in a field soil-strawberry system, cyetpyrafen and M-309 exhibited great accumulations in strawberry leaves by foliar spray while both compounds were predominately accumulated in roots by root irrigation, where cyetpyrafen was poorly translocated within plant. An equal amount of M-309 was measured in both strawberry plants and soils indicates the extensive transformation of cyetpyrafen in soil-strawberry system. Therefore, metabolism of cyetpyrafen in foods need to be considered for its better risk assessment.


Assuntos
Produtos Agrícolas/química , Fragaria , Praguicidas/análise , Solo/química , Água/análise , Produtos Agrícolas/metabolismo , Inseticidas/análise , Inseticidas/metabolismo , Praguicidas/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Água/metabolismo
8.
Sci Total Environ ; 860: 160535, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36574547

RESUMO

Racemates in the environment can lead to inaccurate risk assessment. To obtain the enantiomeric level information of benzovindiflupyr for accurate risk assessment, the absolute configuration of benzovindiflupyr was first confirmed, and the enantioseparation method was developed by supercritical fluid chromatography tandem mass spectrometry. The enantioselectivity for bioactivity and toxicity was investigated, and the mechanism was explored by molecular docking and detecting succinate dehydrogenase (SDH) activity and content of succinate acid. 1S,4R-(-)-benzovindiflupyr was identified as the most active against the six targeted phytopathogens, which showed higher 1.7-54.5 times than 1R,4S-(+)-benzovindiflupyr. Additionally, 1S,4R-(-)-benzovindiflupyr (LD50: 21.54 µg L-1) was 103.7 times more toxic than 1R,4S-(+)-benzovindiflupyr against Daphnia magna. 1S,4R-(-)-benzovindiflupyr had a stronger affinity for SDH and significantly inhibited SDH activity, resulting in an increase in succinate acid in the tricarboxylic acid cycle, while its downstream products, fumaric and L-malic acid were significantly reduced. Moreover, the dissipation behavior of benzovindiflupyr on three vegetables was evaluated. 1S,4R-(-)-benzovindiflupyr was preferentially degraded in tomato, but opposite in leaves. The enantioselectivity in pepper and cucumber leaves was the same as in tomato, while there was no enantioselectivity in pepper and cucumber. The study provides a basis for accurate risk assessment and the development of high-effective and low-risk fungicides.


Assuntos
Fungicidas Industriais , Fungicidas Industriais/química , Simulação de Acoplamento Molecular , Norbornanos/farmacologia , Pirazóis , Estereoisomerismo
9.
Pest Manag Sci ; 79(1): 464-473, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36209490

RESUMO

BACKGROUND: Fall armyworm (Spodoptera frugiperda) is one of the major invasive pests in China, and has been widely controlled by labor-intensive foliar sprays of agrochemicals in maize (Zea mays L.). RESULTS: Systemic bioassay showed that mixtures of chlorantraniliprole (Chlor) and carbaryl (Carb) had dramatically synergistic effect on toxicity to S. frugiperda. Particularly, a mixture of Chlor with Carb at a mass ratio of 2:1 (MCC) exhibited the highest toxicity to S. frugiperda. Therefore, seed treatment of Chlor mixed with Carb was studied as a simple, accurate, efficient and low-cost control technology. Our results showed that MCC treatment shortened the median lethal time and 90% lethal time to S. frugiperda compared to Chlor- and Carb-alone treatments. Meanwhile, smaller leaf consumption by S. frugiperda was recorded under MCC treatment compared to Chlor- and Carb-alone treatments. In field trial, maize-seed treatment with MCC showed efficacy up to 39 days post-emergence in preventing S. frugiperda foliar damage at a low infestation pressure. Moreover, chemical quantification by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) showed that Chlor residues were more absorbed and concentrated in maize leaves of MCC treatment, compared to that of Chlor-alone treatment. CONCLUSION: These results suggested that seed treatment with MCC can be applied to increase the control efficacy and reduce the cost of Chlor-alone treatment for controlling S. frugiperda. The present study provided evidence of an enhanced translocation and accumulation of Chlor residues in maize leaves under MCC treatment, which likely contributed to a synergistic effect against S. frugiperda. © 2022 Society of Chemical Industry.


Assuntos
Carbaril , Zea mays , Carbaril/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Sementes
10.
Environ Int ; 169: 107522, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36137426

RESUMO

As new agrochemicals are continuously introduced into agricultural systems, it is essential to investigate their uptake and metabolism by plants to better evaluate their fate and accumulation in crops and the subsequent risks to human exposure. In this study, the uptake and elimination kinetics and transformation of a novel insecticide, cyetpyrafen, in two model crops (lettuce and rice) were first evaluated by hydroponic experiments. Cyetpyrafen was rapidly taken up by plant roots and reached a steady state within 24 h, and it was preferentially accumulated in root parts with root concentration factors up to 2670 mL/g. An uptake mechanism study suggested that root uptake of cyetpyrafen was likely to be dominated by passive diffusion and was difficult to transport via xylem and phloem. Ten phase I and three phase II metabolites of cyetpyrafen were tentatively identified in the hydroponic-plant system through a nontarget screening strategy. The structures of two main metabolites (M-309 and M-391) were confirmed by synthesized standards. The metabolic pathways were proposed including hydroxylation, hydrolysis, dehydrogenation, dehydration and conjugation, which were assumed to be regulated by cytochrome P450, carboxylesterase, glycosyltransferase, glutathione S-transferases and peroxidase. Cyetpyrafen and its main metabolites (M-409, M-309 and M-391) were estimated to be harmful/toxic toward nontarget organisms by theoretical calculation. The high bioaccumulation and extensive transformation of cyetpyrafen highlighted the necessity for systematically assessing the crop uptake and metabolism of new agrochemicals.


Assuntos
Inseticidas , Hidrolases de Éster Carboxílico/metabolismo , Produtos Agrícolas/metabolismo , Glutationa/metabolismo , Glicosiltransferases/metabolismo , Humanos , Inseticidas/metabolismo , Inseticidas/toxicidade , Peroxidases/metabolismo , Raízes de Plantas/metabolismo , Transferases/metabolismo
11.
Food Chem ; 395: 133571, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-35802974

RESUMO

Fluindapyr is a pyrazolamide chiral fungicide of succinate dehydrogenase inhibitor (SDHIs) with two enantiomers. Pesticide enantiomers often exhibit different biological activities, toxicity due to their different enantioselectivity. Therefore, it is important to separate fluindapyr enantiomers and assess each enantiomer. In this study, fluindapyr enantiomers were baseline separated by supercritical fluid chromatography-mass spectrometry in 2 min. The limit of quantification (LOQ) of this method was 5 µg/kg. The developed method was applied to monitor the fluindapyr enantiomers in cucumber and tomato, the data showed that R-(-)-fluindapyr was preferentially degraded in tomato leaves, S-(+)-fluindapyr was preferentially degraded in cucumber leaves, and fluindapyr enantiomers had no enantioselective degradation behavior in two fruits. It is proved again that enantiomers have different enantioselective degradation behavior with the different plant species and even to different parts of the same plant. The enantioselectivity is likely to be caused by different biodegradation enzyme systems.


Assuntos
Cromatografia com Fluido Supercrítico , Cucumis sativus , Solanum lycopersicum , Cromatografia com Fluido Supercrítico/métodos , Cucumis sativus/química , Solanum lycopersicum/química , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos
12.
Internet Interv ; 28: 100524, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35342718

RESUMO

Background: Compared to its cis-heterosexual counterpart, the sexual and gender minority (SGM) population is disproportionately susceptible to mental health problems, including depression, anxiety, and minority stress. They are also facing unique help-seeking barriers when in need of support. Past research has shown promising results in using interventions to promote help-seeking intentions and attitudes of the cis-heterosexual population. However, there were no known help-seeking interventions targeting the SGM population. This protocol illustrates a study design to test the efficacy of a newly-developed internet-based program aimed to promote help-seeking for mental health in LGBTQ+ young adults. Methods: This study is a randomized controlled trial that aims to promote and improve the SGM young adults' help-seeking by integrating animated psychoeducational videos, group discussion, and the SGM youth help-seeking brochure. Primary outcomes, including help-seeking intentions and attitudes, will be measured at baseline, post-intervention, one-month post-intervention, and three-month post-intervention. The secondary outcomes, including help-seeking stigma, help-seeking literacy, mental health literacy, and help-seeking behaviors, will be measured at the same time points. Discussion: This is an internet-based, multi-dimensional, and integrative intervention tailored to the needs of the SGM population. It addresses an important gap in the current landscape of mental health promotion for the SGM population. The findings from this trial will provide new knowledge on promoting help-seeking among the SGM population, paving the road for future research that focuses on addressing mental health issues faced by the SGM population. Trial registration: Chictr.org.cn: ChiCTR2100053248.

13.
J Sci Food Agric ; 102(6): 2494-2499, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34689325

RESUMO

BACKGROUND: Pesticide contamination in oil crops and processed products is an important food safety concern. The study was aimed to investigate the pesticide residue changes in press processing of peanut oil and frying of chips. RESULTS: Five pesticides - chlorpyrifos, deltamethrin, methoxyfenozide, azoxystrobin and propargite - which are often applied during growth period in peanut plants, were selected to investigate their residue changes in cold press processing of peanut oil and frying of potato chips. Results showed that the residues of the five pesticides were decreased by 3.1-42.6% during air-drying before oil pressing. The residues of chlorpyrifos, deltamethrin, methoxyfenozide and propargite in peanut oil were 2.05-3.63 times higher than that in peanut meal after cold pressing of the oil, except for azoxystrobin having a slightly lower residue in peanut oil, with 0.92 times that in peanut meal. The processing factors of the five pesticides in peanut oil ranged from 1.17 to 2.73 and were highly related to the log Kow of the pesticides. The higher the log Kow , the more easily was the pesticide partitioned in the peanut oil. Besides, as frying time increase during preparation of chips, the concentration of pesticides in peanut oil decreased gradually by 6.7-22.1% compared to the first frying. In addition, 0.47-11.06% of the pesticides were transferred to the chips through frying with contaminated oil. CONCLUSION: This is first report showing that pesticides can transfer from contaminated oil to chips. There exists a potential dietary health risk by using pesticide-contaminated oil for frying chips. This work could provide basic data for accurate dietary risk assessment of pesticide residues in peanut oil and its frying products. © 2021 Society of Chemical Industry.


Assuntos
Clorpirifos , Resíduos de Praguicidas , Praguicidas , Arachis , Culinária , Óleo de Amendoim , Resíduos de Praguicidas/análise , Praguicidas/análise
14.
Food Chem ; 376: 131883, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34971887

RESUMO

A fast, effective, and environmental-friendly method was developed for enantioseparation and analysis of mefentrifluconazole in vegetables based on supercritical fluid chromatography tandem mass spectrometry. The enantioselective behaviors of mefentrifluconazole enantiomers in tomato, cucumber, and pepper in the greenhouse, and pickled cucumber and pepper during processing were investigated. Mefentrifluconazole enantiomers could obtain baseline separation within 2 min. The average recoveries of all matrices ranged from 78.4% to 119.0%, with relative standard deviations less than 16.8% for two enantiomers. S-(+)-mefentrifluconazole was preferentially degraded in pepper, while there was no enantioselectivity in tomato and cucumber under field conditions. During processing, S-(+)-mefentrifluconazole was reduced preferentially than R-(-)-mefentrifluconazole in pickled cucumber and cucumber brine. Inversely, R-(-)-mefentrifluconazole degraded faster than S-(+)-mefentrifluconazole in pepper brine. But, no obvious enantioselectivity was observed in pickled pepper. The result of this study could contribute to a more accurate dietary risk assessment of mefentrifluconazole in vegetables and processed products.

15.
J Sci Food Agric ; 101(13): 5478-5486, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33682082

RESUMO

BACKGROUND: Imazalil is widely used in agriculture, which may pose a threat to food safety. This study aimed to investigate the fate of imazalil and its main metabolite, R14821 (imazalil-M), in field grapes and apples, and in the processing of fruit wine at the enantiomeric level. RESULTS: Analysis method was established to determine imazalil and imazalil-M enantiomers in grape, apple, fruit wine and pomace. The method showed acceptable recoveries of 71.6-99.9% and precision with relative standard deviation of 0.3-11.7%. Processing factors (PFs) were 0.15-0.40 (for imazalil enantiomers) and <0.13-0.83 (for imazalil-M enantiomers) during the wine-making process. The PFs after individual steps including washing, peeling, fermentation, and clarification were all less than 1. No enantioselective dissipation of imazalil was found in grapes under field conditions with half-lives of 23.82-24.49 days. R-(-)-imazalil degraded slightly faster than S-(+)-imazalil in apples under field conditions with half-lives of 9.82-10.09 days. S-(+)-imazalil-M preferentially degraded in field grapes and apple. No significant enantioselectivity of imazalil and imazalil-M was observed during the wine-making process. The enantiomeric fraction (EF) values of imazalil were 0.484-0.511 and 0.509-0.522 in grape wine and cider, respectively. The EFs were 0.484-0.501(in grape wine) and 0.484-0.504 (in cider) for imazalil-M. CONCLUSION: The results showed that the wine-making process could reduce imazalil and imazalil-M residues in grapes and apples. The finding of non-enantioselectivity of imazalil during the processing of fruit wine was useful for accurate risk assessment for imazalil in raw and processing fruits. © 2021 Society of Chemical Industry.


Assuntos
Fungicidas Industriais/química , Imidazóis/química , Malus/química , Vitis/química , Vinho/análise , Resíduos de Drogas/química , Resíduos de Drogas/metabolismo , Contaminação de Alimentos/análise , Manipulação de Alimentos , Frutas/química , Frutas/metabolismo , Fungicidas Industriais/metabolismo , Imidazóis/metabolismo , Malus/metabolismo , Estereoisomerismo , Vitis/metabolismo
16.
J Sep Sci ; 43(21): 4077-4087, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32860653

RESUMO

Oxathiapiprolin is a chiral fungicide used in China for the prevention and treatment of grape downy mildew, but its potential risk could be inaccurately assessed without distinguishing its enantiomers. In this study, an effective and sensitive chiral analytical method was first established for quantification of oxathiapiprolin enantiomers using supercritical fluid chromatography tandem mass spectrometry. Baseline separation for oxathiapiprolin enantiomers was achieved for less than 3 min by using a Lux Cellulose-2 chiral column with the resolution of 1.51. The elution order of the eluting enantiomers was identified as (-)-oxathiapiprolin and (+)-oxathiapiprolin by an optical rotation detector. The grape samples were extracted by QuEChERS method, with the average recoveries of each enantiomer in grapes were in the range of 88.1-111.8% and the relative standard deviations were less than 18.9%. The enantioselective analysis of the dissipation of oxathiapiprolin in field grape samples showed that (-)-oxathiapiprolin was dissipated faster than (+)-oxathiapiprolin. The results indicate that this proposed method could provide data support for the risk assessment of oxathiapiprolin in agricultural produces in a more accurate way.


Assuntos
Fungicidas Industriais/análise , Hidrocarbonetos Fluorados/análise , Pirazóis/análise , Poluentes do Solo/análise , Vitis/química , Cromatografia com Fluido Supercrítico , Estrutura Molecular , Estereoisomerismo , Espectrometria de Massas em Tandem
17.
Ying Yong Sheng Tai Xue Bao ; 31(3): 872-882, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32537983

RESUMO

Effects of elevated atmospheric CO2 concentration and temperature on rice dry matter accumulation vary in planting regions and cropping systems. It remains unclear how dry matter productivity responds to factorial combination of elevated CO2 and temperature in the double rice cropping system of China. Field experiments were conducted using open-top chambers (OTC) to simulate different scenarios of elevated CO2 and/or temperature for three rotations of double rice in Jingzhou, Hubei Province. Liangyou 287 and Xiangfengyou 9 were used as rice cultivar for early rice and late rice, respectively. There were five treatments: UC, paddy field without OTC covering; CK, OTC with the similar temperature and CO2 concentration to field environment; ET, OTC with 2 ℃ temperature elevation; EC, OTC with 60 µmol·mol-1 CO2 elevation; ETEC, OTC with simu-ltaneous 2 ℃ temperature elevation and 60 µmol·mol-1 CO2 elevation. We measured aboveground biomass, leaf area index (LAI) and net assimilation rate (NAR) of dry matter under different treatments. Our results showed that elevated CO2 and/or temperature had no significant effects on NAR from transplanting to jointing, increased NAR from jointing to heading, but decreased NAR from heading to maturity (except for EC treatment in early rice). Elevated CO2 and/or temperature promoted leaf area development at all growth stages, with ETEC showing the highest increase in LAI except at maturity. Warming and CO2 enrichment jointly promoted dry matter accumulation at heading, with ETEC increasing aboveground biomass by 10.3%-39.8% and 23.6%-34.4% compared with CK in early rice and late rice, respectively. At maturity of early rice, elevated temperature partly offset the positive effects of elevated CO2 on aboveground biomass, as shown by a reduction of 3.2%-14.1% under ETEC compared with EC. Contrarily at maturity of late rice, co-elevation of CO2 and temperature further increased aboveground biomass, showing a synergistic interaction. Results from regression analysis showed that warming and CO2 enrichment had positive effects on NAR at vegetative stages of double rice, while warming showed negative effects on NAR at reproductive stages. Considering the dissimilarities in growth characteristics, growing periods and ambient temperature, elevated CO2 and temperature might increase dry matter production in the Chinese double rice cropping system.


Assuntos
Oryza , Biomassa , Dióxido de Carbono , China , Folhas de Planta , Temperatura
18.
Sci Total Environ ; 733: 139069, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32446056

RESUMO

Zoxamide is a recently discovered chiral fungicide that applied to agricultural production, but the potential environmental risk may be underestimated because the risk posed by either enantiomer has not been adequately assessed. Therefore, systemic evaluation of zoxamide was first carried out at the enantiomeric level. Enantioselective bioactivity against target pathogens (Phytophthora capsici Leonian, Alternaria solani, Botryis cinerea, Colletotrichum gloeosprioides Penz, Phytophthora sojae Kaufmann & Gerdemann) was explored, and the order of the bioactivity was R-zoxamide >Rac-zoxamide >S-zoxamide, with a 9.9- to 140.0-times difference between two enantiomers. Molecular docking simulation was utilized to clarify the mechanism underlying the observed differences in enantioselective bioactivity, and the result indicated that a difference of Van der waals force between R/S-zoxamide and the specific receptor gave rise to the different antifungal activity. The enantioselective toxicity result demonstrated that R-zoxamide had 4.9- to 10.8- times greater acute toxicity to Selenastrum capricornutum and Daphnia magna than S-zoxamide. S-zoxamide degraded faster under aerobic condition in all three types of soils, giving rise to an enrichment of high-risk R-enantiomer. Under anaerobic condition, however, no significant difference in dissipation rate was observed between two enantiomers. R-zoxamide was 1.5- to 3.5-times more bioactive and 1.1- to 1.5-times more toxic than Rac-zoxamide, which means developing R-zoxamide instead of racemate is a potential way to reduce pesticide dosage without loss of efficacy against target organisms and that an inactive isomer would no more be released to the environment. This study may have implications for better practical application and environmental risk assessment of zoxamide enantiomers.


Assuntos
Fungicidas Industriais , Triazóis , Amidas , Animais , Simulação de Acoplamento Molecular , Estereoisomerismo
19.
Syst Biol Reprod Med ; 66(2): 99-111, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32040351

RESUMO

The adverse effects of sleep disorders on male fertility are of increased concern. In this study, a rat model of chronic sleep restriction (CSR) was established using the modified multiplatform method. The effects of CSR on the fertility of male rats were evaluated first based on sexual behavior. Serum hormones, including testosterone (T), prolactin (PRL), luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and sperm parameters (concentration, viability, motility, deformation rate) were measured, and testicular histology was analysed by hematoxylin and eosin staining. The transcriptional differences between CSR rats and control rats were detected by RNA sequencing (RNA-Seq), and DNA methylation was then detected by bisulfite sequencing. After the differentialy expressed genes of CSR rats were sequenced and screened, representative up- and down-regulated genes were randomly sampled to verify the sequencing results by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). Finally, functional annotations were completed, including gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomic (KEGG) pathway analyses. The results showed that the sexual behavior of CSR rats did not change when compared with control group rats. The sperm concentration, viability and motility of the CSR rats decreased significantly, while the sperm malformation rate increased significantly. In the KEGG pathway analysis database, some specific differentially expressed genes were screened, which are involved in metabolic pathways, inflammation-related pathways, the renin-angiotensin system, as well as others. However, the aforesaid differentially expressed genes in the testes were not related to their DNA methylation status. CSR could significantly reduce the fertility of male rats, and one of its mechanisms occurs by altering gene expression in the testes, which is not related to their  state of  DNA methylation. The results of this study suggest that CSR could cause male infertility by significantly altering the testicular transcriptome.Abbreviations: CSR: chronic sleep restriction; SD: sleep deprivation; RNA-Seq: RNA sequencing; NGS: next generation sequencing; qRT-PCR: real-time quantitative reverse transcription polymerase chain reaction; KEGG: Kyoto encyclopedia of genes and genomic; NO: nitric oxide; INOS: Inducible nitric oxide synthase; Il6: interleukin-6; Tnf: tumour necrosis factor alpha; Hsd11b1: hydroxysteroid 11-beta dehydrogenase 1; Dnmt3a: DNA methyltransferase 3Ax; PSD: paradoxic sleep deprivation; DNMTs: DNA methyltransferases family; REM: rapid eye movement sleep; PGD: preimplantation genetic diagnosis; PGS: preimplantation genetic screening; ECS: expanded carrier screening; T: testosterone; FSH: follicle stimulating hormone; LH: luteinizing hormone; PRL: prolactin; BC group: Blank Control group; MC group: Model Control group; Hist1h2ba: histone cluster 1 H2ba; Lgr4: leucine-rich repeat-containing G protein-coupled receptor 4; Atrn: attractin ; Ogg1: 8-oxoguanine DNA glycosylase; SNVs: single nucleotide variants ; HPG axis: hypothalamic-pituitary-adrenal axis; Star protein: steroid acute regulatory protein; Dmac2l: distal membrane arm assembly complex 2 like; Esr1: estrogen receptor 1; MAPK pathways: mitogen-activated protein kinase pathways; Sos2: SOS Ras/Rho guanine nucleotide exchange factor 2; Jak2: Janus kinase 2; Pik3cb: phosphatidylinositol-4,5-bisphosphate 3-kinase, and catalytic subunit beta; Kras: KRAS proto-oncogene and GTPase; RRBS: reduced representation bisulfite sequencing; DEGs: differently expressed genes; SPF: Specific Pathogen Free; HE: hematoxylin & eosin; DMR: differentially methylated region; GO Analysis: Gene Ontology analysis; SINE: short interspersed nuclear elements; LINE: long interspersed nuclear elements; LTR: long terminal repeats.


Assuntos
Regulação da Expressão Gênica/genética , Infertilidade Masculina/etiologia , Infertilidade Masculina/genética , Privação do Sono/complicações , Privação do Sono/genética , Animais , Sequência de Bases , DNA/biossíntese , Metilação de DNA , Hormônios Esteroides Gonadais/sangue , Masculino , Ratos , Ratos Wistar , Comportamento Sexual Animal , Testículo/metabolismo
20.
Emerg Infect Dis ; 26(1): 81-89, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855142

RESUMO

In 2018, we conducted a cross-sectional study to investigate azole resistance in environmental Aspergillus fumigatus isolates obtained from different agricultural fields in China. Using 63 soil cores, we cultured for azole-resistant A. fumigatus and characterized isolates by their cyp51A gene type, short tandem repeat genotype, and mating type. Of 206 A. fumigatus isolates, 21 (10.2%) were azole resistant. Nineteen of 21 had mutations in their cyp51A gene (5 TR34/L98H, 8 TR34/L98H/S297T/F495I, 6 TR46/Y121F/T289A). Eighteen were cultured from soil samples acquired from strawberry fields, suggesting this soil type is a potential hotspot for azole resistance selection. Twenty resistant isolates were mating type MAT1-1, suggesting asexual sporulation contributed to their evolution. Prochloraz, difenoconazole, and tebuconazole were the most frequently detected fungicides in soil samples with azole-resistant fungus. Our study results suggest that managing the fungicides used in agriculture will help contain the problem of antifungal drug resistance in clinics.


Assuntos
Aspergillus fumigatus/efeitos dos fármacos , Produção Agrícola , Fragaria , Fungicidas Industriais/farmacologia , Aspergillus fumigatus/genética , Aspergillus fumigatus/isolamento & purificação , China/epidemiologia , Estudos Transversais , Farmacorresistência Fúngica/genética , Técnicas de Genotipagem , Testes de Sensibilidade Microbiana , Repetições de Microssatélites/genética , Filogenia , Análise de Sequência de DNA , Microbiologia do Solo
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