Residue analysis and dietary risk assessment of abamectin in fresh corn, bitter melon, and Fritillaria.

To clarify the residue behavior and possible dietary risk of abamectin in fresh corn, bitter melon, and Fritillaria, a method was developed for the simultaneous determination of abamectin residues in fresh corn, bitter melon, and Fritillaria by QuEChERS (quick, easy, cheap, effective, rugged, safe) ultra-performance liquid chromatography-tandem mass spectrometry. The mean recovery of abamectin in fresh corn, bitter melon, and Fritillaria was 86.48%-107.80%, and the relative standard deviation was 2.07%-10.12%. The detection rates of abamectin residues in fresh corn, bitter melon, and Fritillaria were 62.50%, 87.50%, and 80.00%, respectively. The residues of abamectin in fresh corn, bitter melon, and Fritillaria were not more than 0.020, 0.019, and 0.087 mg/kg, respectively. Based on these results, dietary risk assessment showed that the risk content of abamectin residues in long- and short-term dietary exposure for Chinese consumers was 61.57% and 0.41%-1.11%, respectively, indicating that abamectin in fresh corn, bitter melon, and Fritillaria in the market would not pose a significant risk to consumers.

Waterborne Tebuconazole Exposure Induces Male-Biased Sex Differentiation in Zebrafish (Danio rerio) Larvae via Aromatase Inhibition.

Tebuconazole is a widely used fungicide for various crops that targets sterol 14-α-demethylase (CYP51) in fungi. However, attention has shifted to aromatase (CYP19) due to limited research indicating its reproductive impact on aquatic organisms. Herein, zebrafish were exposed to 0.5 mg/L tebuconazole at different developmental stages. The proportion of males increased significantly after long-term exposure during the sex differentiation phase (0-60, 5-60, and 19-60 days postfertilization (dpf)). Testosterone levels increased and 17ß-estradiol and cyp19a1a expression levels decreased during the 5-60 dpf exposure, while the sex ratio was equally distributed on coexposure with 50 ng/L 17ß-estradiol. Chemically activated luciferase gene expression bioassays determined that the male-biased sex differentiation was not caused by tebuconazole directly binding to sex hormone receptors. Protein expression and phosphorylation levels were specifically altered in the vascular endothelial growth factor signaling pathway despite excluding the possibility of tebuconazole directly interacting with kinases. Aromatase was selected for potential target analysis. Molecular docking and aromatase activity assays demonstrated the interactions between tebuconazole and aromatase, highlighting that tebuconazole poses a threat to fish populations by inducing a gender imbalance.

Graph Sampling-Based Multi-Stream Enhancement Network for Visible-Infrared Person Re-Identification.

With the increasing demand for person re-identification (Re-ID) tasks, the need for all-day retrieval has become an inevitable trend. Nevertheless, single-modal Re-ID is no longer sufficient to meet this requirement, making Multi-Modal Data crucial in Re-ID. Consequently, a Visible-Infrared Person Re-Identification (VI Re-ID) task is proposed, which aims to match pairs of person images from the visible and infrared modalities. The significant modality discrepancy between the modalities poses a major challenge. Existing VI Re-ID methods focus on cross-modal feature learning and modal transformation to alleviate the discrepancy but overlook the impact of person contour information. Contours exhibit modality invariance, which is vital for learning effective identity representations and cross-modal matching. In addition, due to the low intra-modal diversity in the visible modality, it is difficult to distinguish the boundaries between some hard samples. To address these issues, we propose the Graph Sampling-based Multi-stream Enhancement Network (GSMEN). Firstly, the Contour Expansion Module (CEM) incorporates the contour information of a person into the original samples, further reducing the modality discrepancy and leading to improved matching stability between image pairs of different modalities. Additionally, to better distinguish cross-modal hard sample pairs during the training process, an innovative Cross-modality Graph Sampler (CGS) is designed for sample selection before training. The CGS calculates the feature distance between samples from different modalities and groups similar samples into the same batch during the training process, effectively exploring the boundary relationships between hard classes in the cross-modal setting. Some experiments conducted on the SYSU-MM01 and RegDB datasets demonstrate the superiority of our proposed method. Specifically, in the VIS→IR task, the experimental results on the RegDB dataset achieve 93.69% for Rank-1 and 92.56% for mAP.

Residues and Dietary Risk Assessment of Prohexadione-Ca and Uniconazole in Oryza sativa L. and Citrus reticulata Blanco by Liquid Chromatography-Tandem Mass Spectrometry.

A simple and sensitive method for the simultaneous quantitation of prohexadione-Ca and uniconazole in the field experiment of Oryza sativa L. and Citrus reticulata Blanco was established using solid-phase extraction (SPE) with polymer anion exchange (PAX) and Florisil followed by LC-MS/MS. The method demonstrated excellent linearity (R2 > 0.999 0), trueness (recoveries between 95~105%), precision (CVs between 0.8~12%), sensitivity, and repeatability (LOQ of 0.05 and 0.01 mg/kg, respectively). Residue tests were conducted in the field at 12 representative sites in China, revealing final concentrations of prohexadione-Ca and uniconazole in brown rice, rice hull, and rice straw to be below 0.05 mg/kg, while in whole citrus fruit and citrus pulp, they were below 0.01 mg/kg. These were below the maximum residue limits specified in China. The chronic dietary risks of prohexadione-Ca and uniconazole in rice crops and citrus fruits were calculated to be 0.48% and 0.91%, respectively. Our research suggests that the chronic risk associated with the daily consumption of rice crops and citrus fruit at the recommended dosage is acceptable.

Global DNA 5-Hydroxymethylcytosine and 5-Formylcytosine Contents Are Decreased in the Early Stage of Hepatocellular Carcinoma.

Methylation of the fifth position of cytosine (5mC) is an important epigenetic modification of DNA. It has been shown that the oxidized derivatives of 5mC, namely 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC), are in dynamic existence and have distinct regulatory functions. In the current study, we investigated whether there are changes in the contents of all three 5mC-oxidized derivatives in the hepatocellular carcinoma (HCC) genome and further explored the underlying mechanisms. We showed that both global genomic 5hmC and 5fC contents were decreased significantly in the very early stage (stage 0, Barcelona Clinic Liver Cancer [BCLC] staging) of HCC compared with those of paratumor tissues. Noteworthily, 5fC content continued to decrease in the late stage (BCLC staging from 0 to A) of HCC. The 5caC content in HCC tissues was below the detection threshold. Hepatitis B virus (HBV) infection was associated with 5mC, 5hmC, or 5fC decrease in HCC; and measurements in cell lines integrated with or without HBV DNA showed consistent results. On the other hand, both the expression level of ten-eleven translocation enzyme 2 (TET2) and α-ketoglutarate content were decreased significantly in HCC. The significantly positive correlations among the expression levels of DNA methylation-related enzymes in paratumor tissues were generally attenuated or even disappeared in HCC tumor tissues. The decreases of both 5hmC and 5fC contents in genomic DNA were associated with poor prognosis of HCC patients. Conclusion: Global 5hmC and 5fC contents were decreased significantly in the very early stage of HCC; the decrease of 5hmC and 5fC was mainly due to the decrease of 5mC and associated with HBV infection, decreased TET enzyme activity, and uncoordinated expression of DNA methylation-related enzymes.

Gingival crevicular fluid levels of SLIT3 are increased in periodontal disease.

This study aims to investigate the levels of SLIT3 in gingival crevicular fluid (GCF) of healthy and periodontal disease subjects, and their correlations to periodontal disease. A total of 45 periodontal patients and 45 periodontally healthy volunteers were enrolled. The clinical parameters, radiographic bone loss and the levels of SLIT3, receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) in GCF were measured. The prevalences of Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia in subgingival plaque were also analyzed. The expression of SLIT3 and RANKL was detected in the periodontium of experimental periodontitis in rats and lipopolysaccharide (LPS)-induced mouse macrophage. The total amounts and concentrations of SLIT3 and RANKL were significantly higher in periodontitis than those in healthy, while the level of OPG was significantly lower (p < .05). Significant positive correlations were observed between the level of GCF SLIT3 and clinical attachment level and radiographic bone loss (p < .05). There existed a significant positive correlation between SLIT3 and RANKL (p < .05). Increased expression of SLIT3 and RANKL was observed in the periodontium of periodontal rats. SLIT3 expression was induced by LPS stimulation in macrophages. These results suggest that SLIT3 may act as a diagnostic indicator of periodontal disease and should be further investigated.

Design, synthesis, and biological evaluation of novel 2'-deoxy-2'-fluoro-2'-C-methyl 8-azanebularine derivatives as potent anti-HBV agents.

Hepatitis B virus (HBV) is a global health problem requiring more efficient and better tolerated anti-HBV agent. In this paper, a series of novel 2'-deoxy-2'-fluoro-2'-C-methyl-ß-d-arabinofuranosyl 8-azanebularine analogues (1 and 2a) and N4-substituted 8-azaadenosine derivatives (2b-g) were designed, synthesized and screened for in vitro anti-HBV activity. Two concise and practical synthetic routes were developed toward the structural motif construction of 2'-deoxy-2'-fluoro-2'-C-methyl-ß-d-arabinofuranosyl 8-azainosine from the ribonolactone 3 under mild conditions. The in vitro anti-HBV screening results showed that these 8-azanebularine analogues had a significant inhibitory effect on the expression of HBV antigens and HBV DNA at a concentration of 20 µM. Among them, halogen-substituted 8-azaadenosine derivative 2g displayed activities comparable to that of 3TC. In particular, 2g retained excellent activity against lamivudine-resistant HBV mutants.

Synergistic potential of fenvalerate and triadimefon on endocrine disruption and oxidative stress during rare minnow embryo development.

Pyrethroids have been reported to interact synergistically when co-exposed with azoles fungicides in different organisms. In the present study, we investigated the mixture toxicity of fenvalerate (FEN) and triadimefon (TDF) toward embryos of Gobiocypris rarus after 96 h exposure. Results demonstrated that TDF enhanced the acute toxicity of FEN. Exposure to binary mixtures of FEN and TDF resulted in synergistic responses of endocrine disruption by inducing the transcripts of several genes including vtg, erα, erß1, erß2, cyp19a, cyp1a, cyp4, cyp11a, gnrh3, gnrhr1a, star, and dmrt1. Furthermore, FEN and TDF mixture increased the VTG level and aromatase activity in rare minnow embryos. FEN and TDF co-exposure also regulated the mRNA of vezf, hsp70, p53, gadd45α, induced the synthesis of ROS and activity of GST, suggesting the synergistic potential of oxidative stress induced by FEN and TDF co-exposure. The results indicated that binary mixtures of FEN and TDF could simultaneously induce endocrine disruption and oxidative stress in a synergistic manner during rare minnow embryo development.

Effects of the antiretroviral drug 2'-deoxy-2'-ß-fluoro-4'-azidocytidine (FNC) on P-gp, MRP2 and BCRP expressions and functions.

The purpose of the present study was to dig into recent studies designed to characterize the impacts of 2'-deoxy-2'-ß-fluoro-4'-azidocytidine (FNC) on P-glycoprotein (P-gp), multidrug resistance-associated protein 2 (MRP2) and breast cancer resistance protein (BCRP). Specifically, the modulation effects of FNC on P-gp, MRP2 and BCRP protein expressions were assessed by western blot methods. 5 (and 6)-Carboxy-2',7'-dichloroflourescein (CDF) and BODIPY-prazosin were used to provide indications of alterations of MRP2 and BCRP activities. The effects of P-gp, MRP2 and BCRP on FNC were evaluated in the in situ single-pass intestinal perfusion model. The results showed that FNC at higher concentrations and with longer incubation times can upregulate the protein expression of P-gp, MRP2 and BCRP in Caco-2 cells. The upregulated proteins were also functionally active, as revealed by a lower degree of CDF and BODIPY-prazosin uptake by the cell monolayers. The intestinal absorptive coefficient (Peff) was observed to significantly increase with the inhibitors of P-gp, MRP2 and BCRP. These results suggested that FNC could modulate the expressions and functions of P-gp, MRP2 and BCRP, while P-gp, MRP2 and BCRP were involved in the efflux transport of FNC. The inductive effects of FNC on P-gp, MRP2 and BCRP suggested the possibility of FNC to contribute to the inter- and intra-individual variability of itself, as well as to alter the absorption of other drugs that may be administered concomitantly.

Individual and combined toxic effects of herbicide atrazine and three insecticides on the earthworm, Eisenia fetida.

In the present study, we evaluated the individual and combined toxic effects of herbicide atrazine and three insecticides (chlorpyrifos, lambda-cyhalothrin and imidacloprid) on the earthworm, Eisenia fetida. Results from 48-h filter paper test indicated that imidacloprid had the highest toxicity to E. fetida with an LC50 of 0.05 (0.041-0.058) µg a.i. cm(-2), followed by lambda-cyhalothrin and atrazine with LC50 values ranging from 4.89 (3.52-6.38) to 4.93 (3.76-6.35) µg a.i. cm(-2), while chlorpyrifos had the least toxicity to the worms with an LC50 of 31.18 (16.22-52.85) µg a.i. cm(-2). Results from 14-days soil toxicity test showed a different pattern of toxicity except that imidacloprid was the most toxic even under the soil toxicity bioassay system. The acute toxicity of atrazine was significantly higher than that of chlorpyrifos. In contrast, lambda-cyhalothrin was the least toxic to the animals under the soil toxicity bioassay system. The binary mixture of atrazine-lambda-cyhalothrin and ternary mixture of atrazine-chlorpyrifos-lambda-cyhalothrin displayed a significant synergistic effect on the earthworms under the soil toxicity bioassay. Our findings would help regulatory authorities understand the complexity of effects from pesticide mixtures on non-target organisms and provide useful information of the interaction of various pesticide classes detected in natural environment.

Histone H3K4 methylation regulates hyphal growth, secondary metabolism and multiple stress responses in Fusarium graminearum.

Histone H3 lysine 4 methylation (H3K4me) is generally associated with actively transcribed genes in a variety of eukaryotes. The function of H3K4me in phytopathogenic fungi remains unclear. Here, we report that FgSet1 is predominantly responsible for mono-, di- and trimethylation of H3K4 in Fusarium graminearum. The FgSET1 deletion mutant (ΔFgSet1) was crippled in hyphal growth and virulence. H3K4me is required for the active transcription of genes involved in deoxynivalenol and aurofusarin biosyntheses. Unexpectedly, FgSet1 plays an important role in the response of F. graminearum to cell wall-damaging agents via negatively regulating phosphorylation of FgMgv1, a core kinase in the cell wall integrity pathway. In addition, ΔFgSet1 exhibited increased resistance to the transcription elongation inhibitor mycophenolic acid. Yeast two-hybrid assays showed that FgSet1 physically interacts with multiple proteins including FgBre2, FgSpp1 and FgSwd2. FgBre2 further interacts with FgSdc1. Western blotting analyses showed that FgBre2 and FgSdc1 are associated with H3K4me. Both proteins are also involved in regulating deoxynivalenol biosynthesis and in responses to mycophenolic acid and cell wall-damaging agents. Taken together, these data indicate that H3K4me plays critical roles not only in regulation of fungal growth and secondary metabolism but also in multiple stress responses in F. graminearum.

The tubulin cofactor A is involved in hyphal growth, conidiation and cold sensitivity in Fusarium asiaticum.

BACKGROUND: Tubulin cofactor A (TBCA), one of the members of tubulin cofactors, is of great importance in microtubule functions through participating in the folding of α/ß-tubulin heterodimers in Saccharomyces cerevisiae. However, little is known about the roles of TBCA in filamentous fungi. RESULTS: In this study, we characterized a TBCA orthologue FaTBCA in Fusarium asiaticum. The deletion of FaTBCA caused dramatically reduced mycelial growth and abnormal conidiation. The FaTBCA deletion mutant (ΔFaTBCA-3) showed increased sensitivity to low temperatures and even lost the ability of growth at 4°C. Microscopic observation found that hyphae of ΔFaTBCA-3 exhibited blebbing phenotypes after shifting from 25 to 4°C for 1- or 3-day incubation and approximately 72% enlarged nodes contained several nuclei after 3-day incubation at 4°C. However, hyphae of the wild type incubated at 4°C were phenotypically indistinguishable from those incubated at 25°C. These results indicate that FaTBCA is involved in cell division under cold stress (4°C) in F. asiaticum. Unexpectedly, ΔFaTBCA-3 did not exhibit increased sensitivity to the anti-microtubule drug carbendazim although quantitative real-time assays showed that the expression of FaTBCA was up-regulated after treatment with carbendazim. In addition, pathogenicity assays showed that ΔFaTBCA-3 exhibited decreased virulence on wheat head and on non-host tomato. CONCLUSION: Taken together, results of this study indicate that FaTBCA plays crucial roles in vegetative growth, conidiation, temperature sensitivity and virulence in F. asiaticum.

Functional analysis of the Fusarium graminearum phosphatome.

Phosphatases are known to play important roles in the regulation of various cellular processes in eukaryotes. However, systematic characterization of the phosphatome has not been reported in phytopathogenic fungi. The wheat scab fungus Fusarium graminearum contains 82 putative phosphatases. The biological functions of each phosphatase were investigated in this study. Although 11 phosphatase genes appeared to be essential, deletion mutants of the other 71 phosphatase genes were obtained and characterized for changes in 15 phenotypes, including vegetative growth, nutrient response and virulence. Overall, the deletion of 63 phosphatase genes resulted in changes in at least one of the phenotypes assayed. Interestingly, the deletion of four genes (Fg06297, Fg03333, Fg03826 and Fg07932) did not dramatically affect hyphal growth, but led to strongly reduced virulence. Western blot analyses showed that three phosphatases (Fg10516, Fg03333 and Fg12867) functioned as negative regulators of the mitogen-activated protein kinase signaling pathways. In addition, we found, for the first time, that FgCdc14 is dispensable for growth, but plays an important role in ribosome biogenesis. Overall, in this first functional characterization of the fungal phosphatome, phosphatases important for various aspects of hyphal growth, development, plant infection and secondary metabolism were identified in the phytopathogenic fungus F. graminearum.

Upregulation of the long noncoding RNA HOTAIR predicts recurrence in stage Ta/T1 bladder cancer.

Stage Ta/T1 urothelial carcinoma of the bladder (Ta/T1 BC) has a marked tendency to recurrence. Long noncoding RNA HOTAIR has been reported to be expressed in some human cancers such as breast cancer, and it may be positively correlated with patient's prognosis. The aim of our study was to evaluate the prognostic value of HOTAIR in Ta/T1 BC. HOTAIR expression in Ta/T1 BC tissues and adjacent normal tissues was collected from 110 patients and measured by real-time quantitative PCR. The relationships between HOTAIR and the clinical pathological characteristics of Ta/T1 BC patients were analyzed. Immunohistochemistry was done to detect the protein of Wnt inhibitory factor 1 (WIF-1) as well. Ninety out of 110 specimens were detected in HOTAIR high expression. Histological grade and expression levels of HOTAIR were positively correlated with the recurrence rate. HOTAIR expression (hazard ratio 4.712; 95 % CI 2.894-8.714; P < 0.001) was an independent predictor of recurrence rate in multivariate Cox regression analysis. HOTAIR expression is correlated with patients' poor prognosis. A significant inverse correlation between HOTAIR and WIF-1 expression was demonstrated in Ta/T1 BC tissues. The expression levels of HOTAIR are an independent prognostic factor of recurrence in Ta/T1 BC patients.

Embryonic exposure to carbendazim induces the transcription of genes related to apoptosis, immunotoxicity and endocrine disruption in zebrafish (Danio rerio).

Carbendazim is one of the most widespread environmental contaminant that can cause major concern to human and animal reproductive system. To date, very few studies have been conducted on the toxic effect of carbendazim in the non-target organism zebrafish (Danio rerio). The study presented here aimed to assess how carbendazim triggers apoptosis, immunotoxicity and endocrine disruption pathways in zebrafish during its embryo development. Our results demonstrated that the expression patterns of many key genes involved in cell apoptosis pathway (e.g. P53, Mdm2, Bbc3 and Cas8) were significantly up-regulated upon the exposure to carbendazim at the concentration of 500 µg/L, while the Bcl2 and Cas3 were down-regulated at the same concentration, interestingly, the expression level of Ogg1 decreased at all the exposure concentrations. It was also observed that the mRNA levels of CXCL-C1C, CCL1, IL-1b and TNFα which were closely related to the innate immune system, were affected in newly hatched zebrafish after exposed to different concentrations of carbendazim. Moreover, the expression of genes that are involved in the hypothalamic-pituitary-gonadal/thyroid (HPG/HPT) axis including VTG, ERα, ERß2, Dio1, Dio2, Thraa and Thrb were all down-regulated significantly after the exposure to carbendazim. The expression levels of two cytochrome P450 aromatases CYP19a and CYP19b were increased significantly after 20 and 100 µg/L carbendazim exposure, respectively. Taken together, our results indicated that carbendazim had the potential to induce cell apoptosis and cause immune toxicity as well as endocrine disruption in zebrafish during the embryo developmental stage. The information presented here also help to elucidate the environmental risks caused by the carbendazim-induced toxicity in aquatic organisms.

[Expression of CCDC67 mRNA and its role in patients with papillary thyroid carcinoma].

OBJECTIVE: To explore the expression of CCDC67 mRNA between papillary thyroid carcinoma (PTC) and adjacent normal tissues. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was employed to detect the expression of CCDC67 mRNA in 48 cases of papillary thyroid carcinoma and their matched adjacent non-cancerous epithelium and cell lines of thyroid carcinoma. RESULTS: There was no expression of CCDC67 mRNA in SW579 and TPC-1 cell line. All cases had the expression of CCDC67 in adjacent normal tissues while the expression of CCDC67 mRNA was down-regulated significantly, only 39.6% (19/48) in 48 cases of thyroid carcinoma. In PTC, the expression rates of CCDC67 mRNA in stage I-II and III-IV were 60% (12/20) and 25% (7/28) and 24.1% (7/29) and 63.2% (12/19) in the lymph node metastasis and non-metastasis groups respectively. Also the expression rates of CCDC67 mRNA in Grades I and II were 61.1% (11/18) and 26.7% (8/30) respectively. And there was significant difference between two groups (P < 0.05). CONCLUSIONS: The down-regulated expression of CCDC67 is one of reasons for inactivation of PTC. And it may play an important role in carcinogenesis and progression of PTC.

Identification and validation of a prognostic model based on four genes related to satellite nodules in hepatocellular carcinoma.

Satellite nodules is a key clinical characteristic which has prognostic value of hepatocellular carcinoma (HCC). Currently, there is no gene-level predictive model for Satellite nodules in liver cancer. For the 377 HCC cases collected from the dataset of Cancer Genome Atlas (TCGA), their original pathological data were analyzed to extract information regarding satellite nodules status as well as other relevant pathological data. Then, this study employed statistical modeling for prognostic model establishment in TCGA, and validation in International Cancer Genome Consortium (ICGC) cohorts and GSE76427. Through rigorous statistical analyses, 253 differential satellite nodules-related genes (SNRGs) were identified, and four key genes related to satellite nodules and prognosis were selected to construct a prognostic model. The high-risk group predicted by our model exhibited an unfavorable overall survival (OS) outlook and demonstrated an association with adverse worse clinical characteristics such as larger tumor size, higher alpha-fetoprotein, microvascular invasion and advanced stage. Moreover, the validation of the model's prognostic value in the ICGC and GSE76427 cohorts mirrored that of the TCGA cohort. Besides, the high-risk group also showed higher levels of resting Dendritic cells, M0 macrophages infiltration, alongside decreased levels of CD8+ T cells and γδT cells infiltration. The prognostic model based on SNRGs can reliability predict the OS of HCC and is likely to have predictive value of immunotherapy for HCC.

Trifloxystrobin induced developmental toxicity by disturbing the ABC transporters, carbohydrate and lipid metabolism in adult zebrafish.

The environmental risks of trifloxystrobin (TR) have drawn attention because of its multiplex toxicity on aquatic organisms, but few studies have paid close attention to its chronic toxicity at environmental concentrations. In present study, histopathology, metabolomics and transcriptomics were comprehensively performed to investigate the toxic effects and biological responses on adult zebrafish after exposure to 0.1, 1 and 10 µg/L TR for 21 d. Results demonstrated long-term exposure of TR affected zebrafish liver, ovary and heart development. Metabolomics revealed 0.1, 1 and 10 µg/L TR simultaneously decreased the carbohydrates enriched in glucose metabolism and ABC transporters pathways, such as glycogen, lactose, lactulose, maltose, maltotriose, d-trehalose, while 1 µg/L and 10 µg/L TR significantly increased many metabolites related to glycerophospholipid and sphingolipid metabolism in zebrafish liver. Transcriptomics showed TR activated the transcription of the Abcb4, Abcb5 and Abcb11 involved in ABC transporters, Pck1, Pfk, Hk, Gyg1a and Pygma related to glucose metabolism, as well as the Lpcat1, Lpcat4, Gpat2, Cers and Sgms in glycerophospholipid and sphingolipid metabolism. Results further demonstrated high concentration of TR strongly affected the DNA repair system, while low dose of TR caused pronounced effects on cardiomyocytes and oocyte regulation pathways at transcriptional levels. The results indicated the abnormal liver, gonad and heart development caused by TR might be ascribed to the disturbance of carbohydrates and lipid metabolism mediating by the Abcb4, Abcb5 and Abcb11 ABC transporters, and long-term exposure of environmental concentration of TR was sufficient to affect zebrafish normal metabolism and development.

[Determination of three new herbicide residues in soil, sediment and water by liquid chromatography-tandem mass spectrometry].

Herbicides play an important role in preventing and controlling weeds and harmful plants and are increasingly used in agriculture, forestry, landscaping, and other fields. However, the effective utilization rate of herbicides is only 20%-30%, and most herbicides enter the atmosphere, soil, sediment, and water environments through drift, leaching, and runoff after field application. Herbicide residues in the environment pose potential risks to ecological safety and human health. Therefore, establishing analytical methods to determine herbicide residues in environmental samples is of great importance. In this study, an analytical method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) in positive electrospray ionization mode (ESI+) was developed for the determination of isoxaflutole, metazachlor, and saflufenacil residues in soil, sediment, and water. The instrumental detection parameters, including electrospray ionization mode, mobile phase, and chromatographic column, were optimized. The mobile phases were methanol (A) and 0.1% formic acid aqueous solution (B). Gradient elution was performed as follows: 0-1.0 min, 60%A; 1.0-2.0 min, 60%A-90%A; 2.0-3.0 min, 90%A; 3.0-4.0 min, 90%A-60%A; 4.0-5.0 min, 60%A. The samples were salted after extraction with acetonitrile and cleaned using a C18 solid-phase extraction column. Different solid-phase extraction columns and leaching conditions were investigated during sample pretreatment. Working curves in the neat solvent and matrix were constructed by plotting the measured peak areas as a function of the concentrations of the analytes in the neat solvent and matrix. Good linearities were found for isoxaflutole, metazachlor, and saflufenacil in the solvent and matrix-matched standards in the range of 0.0005-0.02 mg/L, with r≥0.9961. The matrix effects of the three herbicides in soil, sediment, and water ranged from -10.1% to 16.5%. The limits of detection (LODs, S/N=3) for isoxaflutole, metazachlor, and saflufenacil were 0.05, 0.01, and 0.02 µg/kg, respectively. The limits of quantification (LOQs, S/N=10) for isoxaflutole, metazachlor, and saflufenacil were 0.2, 0.05, and 0.05 µg/kg, respectively. The herbicides were applied to soil, sediment, and water at spiked levels of 0.005, 0.1, and 2.0 mg/kg, respectively. The average recoveries for isoxaflutole, metazachlor, and saflufenacil in soil, sediment, and water were in the ranges of 77.2%-101.9%, 77.9%-105.1%, and 80.8%-107.1%, respectively. The RSDs for isoxaflutole, metazachlor, and saflufenacil were in the ranges of 1.4%-12.8%, 1.2%-7.7%, and 1.5%-11.5%, respectively. The established method was used to analyze actual samples collected from four different sites in Zhejiang Province (Xiaoshan, Taizhou, Dongyang, and Yuhang) and one site in Heilongjiang (Jiamusi). The proposed method is simple, rapid, accurate, stable, and highly practical. It can be used to detect isoxaflutole, metazachlor, and saflufenacil residues in soil, sediment, and water and provides a reference for monitoring the residual pollution and environmental behavior of herbicides.

A systemic study of cyenopyrafen in strawberry cultivation system: Efficacy, residue behavior, and impact on honeybees (Apis mellifera L.).

The pesticide application method is one of the important factors affecting its effectiveness and residues, and the risk of pesticides to non-target organisms. To elucidate the effect of application methods on the efficacy and residue of cyenopyrafen, and the toxic effects on pollinators honeybees in strawberry cultivation, the efficacy and residual behavior of cyenopyrafen were investigated using foliar spray and backward leaf spray in field trials. The results showed that the initial deposition of cyenopyrafen using backward leaf spray on target leaves reached 5.06-9.81 mg/kg at the dose of 67.5-101.25 g a.i./ha, which was higher than that using foliar spray (2.62-3.71 mg/kg). The half-lives of cyenopyrafen in leaves for foliar and backward leaf spray was 2.3-3.3 and 5.3-5.9 d, respectively. The residues (10 d) of cyenopyrafen in leaves after backward leaf spray was 1.41-3.02 mg/kg, which was higher than that after foliar spraying (0.25-0.37 mg/kg). It is the main reason for the better efficacy after backward leaf spray. However, the residues (10 d) in strawberry after backward leaf spray and foliar spray was 0.04-0.10 and < 0.01 mg/kg, which were well below the established maximum residue levels of cyenopyrafen in Japan and South Korea for food safety. To further investigate the effects of cyenopyrafen residues after backward leaf spray application on pollinator honeybees, sublethal effects of cyenopyrafen on honeybees were studied. The results indicated a significant inhibition in the detoxification metabolic enzymes of honeybees under continuous exposure of cyenopyrafen (0.54 and 5.4 mg/L) over 8 d. The cyenopyrafen exposure also alters the composition of honeybee gut microbiota, such as increasing the relative abundance of Rhizobiales and decreasing the relative abundance of Acetobacterales. The comprehensive data on cyenopyrafen provide basic theoretical for environmental and ecological risk assessment, while backward leaf spray proved to be effective and safe for strawberry cultivation.