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1.
Front Med (Lausanne) ; 11: 1254467, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38695016

RESUMO

Background: Preeclampsia (PE) is a pregnancy complication defined by new onset hypertension and proteinuria or other maternal organ damage after 20 weeks of gestation. Although non-invasive prenatal testing (NIPT) has been widely used to detect fetal chromosomal abnormalities during pregnancy, its performance in combination with maternal risk factors to screen for PE has not been extensively validated. Our aim was to develop and validate classifiers that predict early- or late-onset PE using the maternal plasma cell-free DNA (cfDNA) profile and clinical risk factors. Methods: We retrospectively collected and analyzed NIPT data of 2,727 pregnant women aged 24-45 years from four hospitals in China, which had previously been used to screen for fetal aneuploidy at 12 + 0 ~ 22 + 6 weeks of gestation. According to the diagnostic criteria for PE and the time of diagnosis (34 weeks of gestation), a total of 143 early-, 580 late-onset PE samples and 2,004 healthy controls were included. The wilcoxon rank sum test was used to identify the cfDNA profile for PE prediction. The Fisher's exact test and Mann-Whitney U-test were used to compare categorical and continuous variables of clinical risk factors between PE samples and healthy controls, respectively. Machine learning methods were performed to develop and validate PE classifiers based on the cfDNA profile and clinical risk factors. Results: By using NIPT data to analyze cfDNA coverages in promoter regions, we found the cfDNA profile, which was differential cfDNA coverages in gene promoter regions between PE and healthy controls, could be used to predict early- and late-onset PE. Maternal age, body mass index, parity, past medical histories and method of conception were significantly differential between PE and healthy pregnant women. With a false positive rate of 10%, the classifiers based on the combination of the cfDNA profile and clinical risk factors predicted early- and late-onset PE in four datasets with an average accuracy of 89 and 80% and an average sensitivity of 63 and 48%, respectively. Conclusion: Incorporating cfDNA profiles in classifiers might reduce performance variations in PE models based only on clinical risk factors, potentially expanding the application of NIPT in PE screening in the future.

2.
PeerJ ; 12: e16554, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188142

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) is a the first and rate-limiting enzyme that plays a critical role in G6PD deficiency, the most common enzyme disorder worldwide, is related to intravascular hemolysis. To determine the clinical enzyme activity level in different G6PD variants, we evaluated 15 variant from 424 clinical blood samples by using multicolor melting curve analysis and DNA sequencing. The results showed that the enzyme activities of the hemizygous deficient were 1.5-2.4 U/gHb, which was significantly lower than those of the heterozygous (P < 0.001) and the compound heterozygous variants (P < 0.05). Since the hemizygous of c.1024C > T (Chinese-5) mutation affects the kinetic parameters of G6PD and increase utilization of analogues, its enzyme activity is more than those of other mutations that mutated in the ß+α region of G6PD. The heterozygous enzyme levels ranged from 6.5-20.1 U/gHb; and there was no significant difference among different heterozygous variants (P > 0.05). The enzyme activity levels of the compound heterozygous mutation were mainly in the range of 1.7-3.8 U/gHb, which was much lower than that of the heterozygous mutation (P < 0.001). In summary, our findings revealed that the enzyme activity of G6PD in blood have a significant relationship with genotype of G6PD.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Humanos , Genótipo , Deficiência de Glucosefosfato Desidrogenase/genética , Testes Hematológicos
3.
Food Chem X ; 20: 100904, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37817988

RESUMO

This study investigated the effect of electron beam irradiation (EBI) on the lipid stability of oat and barley during long-term storage. Results showed that the initial free fatty acid content in oat was higher than that in barley. This may mean that lipid hydrolysis started under the function of lipase when oat and barley were milled into flours. Both storage and EBI factors influenced lipid-degrading enzyme activity and promoted lipid oxidation in oat and barley. However, it seemed that storage had higher impacts because the DPPH scavenging activity decreased greatly, and the contents of both malondialdehyde and volatile lipid oxidation products increased in all samples. Thus, the antioxidant capacity and level of lipid oxidation after EBI treatment should be considered when producing oat and barley foods. Overall, this study shows the high potential of EBI for use as a non-thermal technique in stabilising the storage quality of oat and barley.

4.
Mol Genet Genomic Med ; 11(10): e2229, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37337789

RESUMO

BACKGROUND: The identification of genetic mosaicism and the genetic counseling needed following its discovery have been challenging problems in the field of prenatal diagnosis. Herein, we describe the clinical phenotypes and various prenatal diagnostic processes used for two rare cases of 9p duplication mosaicism and review the prior literature in the field to evaluate the merits of different methods for diagnosing mosaic 9p duplication. METHODS: We recorded ultrasound examinations, reported the screening and diagnosis pathways, and analyzed the mosaic levels of the two cases of 9p duplication using karyotype analysis, chromosomal microarray analysis (CMA), and fluorescence in situ hybridization analysis (FISH). RESULTS: Case 1 had a normal clinical phenotype for tetrasomy 9p mosaicism, and Case 2 showed multiple malformations caused by both trisomy 9 and trisomy 9p mosaicism. Both cases were initially suspected after non-invasive prenatal screening (NIPT) based on cell-free DNA. The mosaic ratio of 9p duplication found via karyotyping was lower than what was discovered by CMA and FISH, in both cases. Contrary to previous findings, the mosaic level of trisomy 9 found by karyotype analysis was greater than what was found by CMA, in terms of complex mosaicism involving trisomy 9 and trisomy 9p, in Case 2. CONCLUSION: NIPT can indicate 9p duplication mosaicism during prenatal screening. Different strengths and limitations existed in terms of diagnosing mosaic 9p duplication by karyotype analysis, CMA, and FISH. The combined use of various methods may be capable of more accurately determining break-points and mosaic levels of 9p duplication during prenatal diagnosis.

5.
Environ Int ; 178: 108028, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37343326

RESUMO

Due to their ubiquity and potential risks, microplastics (MPs) and nanoplastics (NPs) are concerning environmental issues. Yet there are still significant knowledge gaps in understanding the tissue-specific accumulation and dynamic change of MPs and NPs in the aquatic organism and how these micro/nano-scale emerging contaminants interact with other environmental pollutants such as persistent organic pollutants (POPs). Here, in vivo imaging systems (IVIS), radioisotope tracing, and histological staining were innovatively used to reveal the fate and toxicity of fluorescently-labeled MPs/NPs and 14C-labeled 2,4,4'-trichlorobiphenyl (PCB28) in edible jellyfish Rhopilema esculentum. These contaminants' ingestion, biological effects, and interactions were visualized at cellular, tissue, and whole-body multidimensional levels. Both MPs and NPs were shown to be preferentially accumulated in the mouthlets of oral arms, and most ingested MPs/NPs were present in the extracellular environment instead of being internalized into the mesoglea. Moreover, the presence of MPs or NPs in the seawater significantly inhibited the bioaccumulation of PCB28 in the jellyfish tissue, thus alleviating physiological alteration, gastric damage, and apoptosis caused by PCB28. This study provides a multi-dimensional visualization strategy to display the distribution and biological effects of typical pollutants in marine organisms and offers new insights for understanding the impacts of MPs/NPs and POPs on marine ecosystems.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Microplásticos/toxicidade , Plásticos/toxicidade , Ecossistema , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Organismos Aquáticos , Ingestão de Alimentos
6.
J Hazard Mater ; 445: 130583, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-37055988

RESUMO

As a best-selling triazolinthione fungicide, prothioconazole (PTZ) has been widely used worldwide and has aroused concern about its environmental effect. This study used phenyl-UL-14C-labeled PTZ and an improved fate model to investigate the fate and metabolism of this fungicide in aerobic soil. During 120 d of incubation, PTZ rapidly transformed into metabolites and bound residues, with a half-life (DT50) of less than 1 d. After 120 d, approximately 45-55% of PTZ formed bound residues, and the extractable metabolite residues were gradually degraded over time. Approximately 19%, 44% and 27% of phenyl-UL-14C-PTZ was mineralized in red soil, fluvo-aquic soil and cinnamon soil, respectively, but only approximately 3% was mineralized in black soil. Five metabolites were identified and confirmed, and a possible metabolic pathway for phenyl-UL-14C-PTZ in soil was proposed. Based on the correlation analysis between soil properties and model rate constants, soil properties exerted important effects on PTZ transformation. These results will provide basic data for environmental risk assessments and removal of the PTZ pollutant and suggest that the soil type should be considered in the selection and application of pesticides.


Assuntos
Fungicidas Industriais , Praguicidas , Poluentes do Solo , Fungicidas Industriais/química , Solo/química , Poluentes do Solo/análise
7.
Sci Total Environ ; 880: 163312, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030363

RESUMO

Dufulin is a promising chiral antiviral agent, but little is known about its fate in soils. In this study, the fate of dufulin enantiomers in aerobic soils was investigated using radioisotope tracing techniques. The result of the four-compartment model showed no significant differences in dissipation, generation of bound residues (BR) and mineralization between S-dufulin and R-dufulin during incubation. Dufulin dissipated most quickly in cinnamon soils, followed by fluvo-aquic and black soils and the half-lives of dufulin in these soils obtained by the modified model were 4.92-5.23, 32.39-33.32 and 60.80-61.34 d, respectively. After 120 d incubation, the percentage of radioactivity of BR increased to 18.2-38.4 % in the three soils. Dufulin formed most bound residues in the black soil, least in the cinnamon soil, and BRs rapidly formed in the cinnamon soil during the early culture period. In these three soils, the cumulative mineralization of 14CO2 ranged from 25.0 to 26.7 %, 42.1 to 43.4 % and 33.8 to 34.4 %, respectively, which indicated that the environmental fate of dufulin was primarily influenced by soil characteristics. The study of microbial community structure revealed that the phyla Ascomycota, Proteobacteria and genus Mortierella might be related to the degradation of dufulin. These findings provide a reference for assessing the environmental impact and ecological safety of dufulin application.


Assuntos
Praguicidas , Poluentes do Solo , Praguicidas/química , Solo/química , Poluentes do Solo/análise , Benzotiazóis/análise
8.
Sci Total Environ ; 878: 162983, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36958557

RESUMO

Dufulin (DFL), a plant antiviral agent synthesized in China, has been widely used to control viral diseases in rice, tobacco, tomato, and other crops. However, its fate in flooded anaerobic soils, which is essential for environmental risk assessment, remains unknown. Using the 14C tracer technique, the fate of 14C-labeled DFL isomers in flooded anaerobic soils was systematically investigated in this study. Over the 100-day incubation, a small part of 14C-DFL enantiomer was mineralized to 14CO2 (< 10.44 %) or entered the surface water phase (< 6.69 %), with most of the 14C (> 80.40 %) remaining in the subsoil. The residues in all tested soils were gradually converted from extractable residues (ERs) to nonextractable residues (NERs). At the end of incubation, the fraction of 14C-NERs reached 5.38-23.77 %. The half-life (t1/2) of the DFL parent in soil is relatively long under submerged anaerobic conditions, especially in Fluvo-aquic soil, up to 277.26-315.07 days, which exceeds the risk threshold recommended by the Stockholm Convention (< 180 days). Soil type and microbial activity influenced the fate of DFL in flooded soils and microbial analysis showed that 2.0 mg kg-1 DFL had no obvious impact on soil bacterial richness and function. Pseudomonas spp. was estimated to be a potentially efficient degrading genus for DFL. No enantioselective behaviors were detected in this study. This research provides a theoretical basis for evaluating the environmental impact and ecological safety of DFL application.


Assuntos
Praguicidas , Poluentes do Solo , Praguicidas/química , Solo/química , Anaerobiose , Poluentes do Solo/análise
9.
J Neurodev Disord ; 15(1): 6, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737720

RESUMO

BACKGROUND: Neurodevelopmental disorders (NDDs) are a group of disorders induced by abnormal brain developmental processes. The prefrontal cortex (PFC) plays an essential role in executive function, and its role in NDDs has been reported. NDDs are associated with high-risk gene mutations and share partially overlapping genetic abnormalities. METHODS: Neurexins (NRXNs) are related to autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). NRXN1, an essential susceptibility gene for NDDs, has been reported to be associated with NDDs. However, little is known about its key role in NDDs. RESULTS: NRXN1 downregulation in the medial PFC induced anxiety-like behaviors and abnormal social phenotypes with impaired neurite outgrowth in Sh-NRXN1 in prefrontal neurons. Moreover, tandem mass tag (TMT)-based proteomic analysis of rat brain samples showed that NRXN1 downregulation led to significant proteome alterations, including pathways related to the extracellular matrix, cell membrane, and morphologic change. Furthermore, full-automatic immunoblotting analysis verified the differently expressed proteins related to cell morphology and membrane structure. CONCLUSIONS: Our results confirmed the association of NRXN1 with abnormal behaviors in NDDs and provided richer insights into specific prefrontal knockdown in adolescence, potentially expanding the NRXN1 interactome and contributing to human health.


Assuntos
Transtorno do Espectro Autista , Animais , Ratos , Ansiedade , Transtorno do Espectro Autista/genética , Proteínas de Ligação ao Cálcio/genética , Moléculas de Adesão de Célula Nervosa/genética , Crescimento Neuronal , Fenótipo , Córtex Pré-Frontal , Proteômica
10.
Mutagenesis ; 38(2): 109-119, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-36852768

RESUMO

To investigate the distribution of polymorphisms and their frequent haplotypes in the regulatory region of MGMT in residents of high background radiation area (HBRA) and their impacts on transcriptional activity, we collected DNA samples from 83 healthy Chinese residents in HBRA and searched for genetic polymorphisms in the regulatory region of MGMT. Haplotypes were characterized by Haploview analysis. Transcriptional activities of different polymorphism haplotypes were detected by using a dual-luciferase reporter assay. Six genetic polymorphisms were identified within the regulatory region (1024 bp) of MGMT. Linkage disequilibrium (LD) patterns and haplotype profiles were analyzed using the identified genetic polymorphisms. These polymorphisms we found to be in high LD, with a D' of 0.928 (r2 = 0.581) for -808 T>C and -19 C>T, 0.928 (r2 = 0.581) for -797 G>A and -19 C>T in Han Chinese HBRA residents. Complete LD with a D' of 1.0 (r2 = 1.0) was observed between -808 T>C and -797 G>A. Haploview analysis revealed the existence of three polymorphism haplotypes in the core region of regulatory region of MGMT. Using serially truncated regulatory region of human MGMT luciferase reporter gene constructs, we found a 1002 bp (-637 nt to +365 nt) fragment in the MGMT gene was the core region. Dual-luciferase reporter assays showed that different polymorphism haplotypes bearing different variant alleles exhibit distinct transcriptional activities, especially the polymorphism haplotype carrying -19 T has the strongest transcriptional activity. In summary, the present study obtained genetic characteristics of the six polymorphisms in the regulatory region of the MGMT gene in HBRA residents, and the results suggest that different polymorphism haplotypes have significant effects on the transcriptional activity of the MGMT and that the -19 C>T polymorphism may be a functional variant involved in the transcriptional regulation of the MGMT gene.


Assuntos
Radiação de Fundo , Polimorfismo Genético , Humanos , Haplótipos/genética , Regiões Promotoras Genéticas , Luciferases/genética , Polimorfismo de Nucleotídeo Único , Desequilíbrio de Ligação , Frequência do Gene , Metilases de Modificação do DNA/genética , Proteínas Supressoras de Tumor/genética , Enzimas Reparadoras do DNA/genética
11.
J Agric Food Chem ; 71(2): 1139-1148, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36621945

RESUMO

Pesticide use can result in plant residues, which can be ingested by livestock consuming plant-derived feed and appear in manure. When this manure is applied as a fertilizer, pesticides can contaminate plant-soil systems. Few studies have focused on pesticide infiltration from applying pesticide-contaminated manure to land. In this study, the fate of pesticide vanisulfane from chicken manure was studied in radish-soil and cabbage-soil systems assisted by carbon-14 labeling. Vanisulfane and its metabolites mostly appeared as bound residues (BRs) after introduction, and BR release was found at 35 d. Notably, manure contaminated with vanisulfane and its metabolites exhibited higher plant accumulation and phytotoxicity than manure contaminated with only the parent. Four metabolites were identified, and germination toxicity assays illustrated that a metabolite with an aldehyde structure induced phytotoxicity. This study provides valuable information on pesticide contamination from manure and emphasizes the importance of considering pesticide metabolites when assessing environmental risks.


Assuntos
Praguicidas , Poluentes do Solo , Animais , Solo/química , Esterco/análise , Radioisótopos de Carbono , Poluentes do Solo/análise
12.
Sci Total Environ ; 858(Pt 1): 159396, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244481

RESUMO

Dufulin is a new type of plant antiviral agent. However, its metabolism in plants, which is very important for environmental risk assessment, is still unclear. In this study, we used 14C markers at different positions and high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (HPLC-QTOF-MS) to qualitatively and quantitatively analyze dufulin metabolites in cherry radish. By combining ion pairs with unique abundance ratios, we clarified the metabolite structures, inferred the metabolic pathway of dufulin, and clarified the criteria for residues. The extractable residue of dufulin from cherry radish stem and leaf tissues was above 98 % and that in the succulent root was above 87 %. In the stem and leaf tissues and succulent root, dufulin underwent both phase I and phase II metabolism, and four metabolites were produced, including a conjugate of glucose malonate and hydroxylated dufulin, which was confirmed by comparison with a standard. However, the proportions and concentrations of the four metabolites did not meet the residue criteria, so only the dufulin precursor compound was included as a residue. This study provides reliable data for evaluating the impacts of dufulin on the environment and human health and for objectively examining the safety of dufulin.


Assuntos
Raphanus , Humanos , Antivirais , Benzotiazóis/análise , Cromatografia Líquida de Alta Pressão/métodos
14.
J Hazard Mater ; 439: 129677, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36104905

RESUMO

Vanisulfane is a novel plant antiviral agent with promising prospects to prevent and control viral crop diseases. However, human health risk assessment after vanisulfane exposure from animal-derived food products remains limited. To gain insight into the accumulation and biotransformation of vanisulfane in livestock, laying hens were dietary exposed to 14C-vanisulfane. Although more than 80 % of the applied dose was observed in the excreta, vanisulfane and its metabolites accumulated in tissues, especially the liver and kidney, and was found to be transferred to eggs. A total of eight metabolites associated with both phase I and phase II metabolism were identified via 14C tracing and LC-QTOF-MS. Phase I metabolism included oxidation, hydroxylation, dechlorination and demethylation, and phase II metabolism was associated with sulfonic acid and glucuronide conjugation. The high percentages of metabolites in laying hens' tissues and organs, illustrated the active biotransformation of vanisulfane in vivo, which suggests that the marker residues of vanisulfane should consider its major metabolites. A digestive model was also used to determine the digestive fate of vanisulfane. This study improves our understanding of vanisulfane accumulation and biotransformation in laying hens, which will be helpful for risk assessments of foods derived from animals exposed to pesticides.


Assuntos
Exposição Dietética , Praguicidas , Animais , Benzaldeídos , Biotransformação , Galinhas/metabolismo , Feminino , Humanos , Praguicidas/metabolismo
15.
J Hazard Mater ; 440: 129777, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36007361

RESUMO

The excessive use of herbicides had caused serious environmental pollution and ecological problems. Therefore, it is imperative to explore an effective method to reduce herbicide residues and pollution. In the present study, we used superabsorbent hydrogels coated 14C-acetochlor (SH-ACE) to investigate its behavior in different soils under oxic conditions. After 100 days, the mineralization by SH-ACE was increased by 2.3%, 2.5% and 3.3% in the red clay soils, fluvio-marine yellow loamy soils and coastal saline soils, respectively, compared to the control group. This result indicated that the SH-ACE treatment resulted in more complete degradation and detoxification of acetochlor. In addition, the dissipation rates of acetochlor were significantly faster in the SH-ACE treatment, which reduced the persistence of acetochlor. The probable degradation pathways of acetochlor involved dechlorination, hydroxylation, deethoxymethylation, and the formation of thioacetic acid derivatives in the two treatments, but the contents of transformation products were completely different. These findings suggest that the SH-ACE treatment has a significant effect to accelerate the degradation of acetochlor. When developing green pesticides, we emphasize that superabsorbent hydrogel coating treatment should be considered as a promising method for ecological safety in the environment.


Assuntos
Herbicidas , Poluentes do Solo , Argila , Herbicidas/metabolismo , Hidrogéis , Solo , Poluentes do Solo/metabolismo , Toluidinas/análise , Toluidinas/química , Toluidinas/metabolismo
16.
Chemosphere ; 307(Pt 4): 136125, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35995201

RESUMO

Reduced graphene oxide (RGO) is one of common carbon nanomaterials, which is widely used in various fields. Triclosan is an antimicrobial agent added in pharmaceuticals and personal care products. Extensive release of RGO and triclosan has posed potential risks to humans and the environment. The impact of RGO on the fate of triclosan in paddy soil is poorly known. 14C-Triclosan was employed in the present study to determine its distribution, degradation and mineralization in paddy soil mixed with RGO. Compared with the control, RGO (500 mg kg-1) significantly inhibited the mineralization of 14C-triclosan, and reduced its extractability by 6.5%. The bound residues of triclosan in RGO-contaminated soil (100 and 500 mg kg-1) were 2.9-13.3% greater than that of the control at 112 d. RGO also accelerated the dissipation of triclosan, and its degradation products in both treatments and controls were tentatively identified via 14C-labeling method and LC-Q-TOF-MS analysis. The concentrations of the major metabolites (methyl-triclosan and dechlorinated dimer) were inversely related with the concentrations of RGO. RGO at 50 mg kg-1 or lower had a negligible effect on the degradation of triclosan in paddy soil. Triclosan was strongly adsorbed onto RGO-contaminated soil, which may play a vital role in the fate of triclosan in RGO-contaminated paddy soil. Interestingly, RGO had little effect on triclosan-degrading bacteria via soil microbial community analysis. This study helps understand the effects of RGO on the transformation of triclosan in paddy soil, which is of significance to evaluate the environmental risk of triclosan in RGO-contaminated soil.


Assuntos
Poluentes do Solo , Triclosan , Adsorção , Carbono , Grafite , Humanos , Preparações Farmacêuticas , Solo , Poluentes do Solo/análise , Triclosan/análise
17.
Nature ; 609(7927): 616-621, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35917926

RESUMO

The PIN-FORMED (PIN) protein family of auxin transporters mediates polar auxin transport and has crucial roles in plant growth and development1,2. Here we present cryo-electron microscopy structures of PIN3 from Arabidopsis thaliana in the apo state and in complex with its substrate indole-3-acetic acid and the inhibitor N-1-naphthylphthalamic acid (NPA). A. thaliana PIN3 exists as a homodimer, and its transmembrane helices 1, 2 and 7 in the scaffold domain are involved in dimerization. The dimeric PIN3 forms a large, joint extracellular-facing cavity at the dimer interface while each subunit adopts an inward-facing conformation. The structural and functional analyses, along with computational studies, reveal the structural basis for the recognition of indole-3-acetic acid and NPA and elucidate the molecular mechanism of NPA inhibition on PIN-mediated auxin transport. The PIN3 structures support an elevator-like model for the transport of auxin, whereby the transport domains undergo up-down rigid-body motions and the dimerized scaffold domains remain static.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácidos Indolacéticos , Apoproteínas/química , Apoproteínas/metabolismo , Apoproteínas/ultraestrutura , Arabidopsis/química , Arabidopsis/metabolismo , Arabidopsis/ultraestrutura , Proteínas de Arabidopsis/antagonistas & inibidores , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/ultraestrutura , Transporte Biológico/efeitos dos fármacos , Microscopia Crioeletrônica , Ácidos Indolacéticos/química , Ácidos Indolacéticos/metabolismo , Ftalimidas/química , Ftalimidas/farmacologia , Domínios Proteicos , Multimerização Proteica , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo
18.
Sci Total Environ ; 846: 157377, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35843335

RESUMO

As triclosan is used extensively as an antimicrobial agent, it inevitably enters agroecosystems, when sewage and treated wastewater are applied to agricultural fields. As a result, triclosan can be accumulated into crops and vegetables. Currently, limited information is available on the metabolism of triclosan in vegetables. In this study, the fate of 14C-triclosan in celery under a hydroponic system was investigated in a 30-day laboratory test. Most (97.7 %) of the 14C-triclosan accumulated in celery. The bioconcentration factors of triclosan were up to 3140 L kg-1 at day 30. The concentration of 14C-triclosan in roots (17.8 mg kg-1) was 57- and 127-fold higher than that in stems (0.31 mg kg-1) and leaves (0.14 mg kg-1), respectively, at day 30, suggesting a higher accumulation of triclosan in celery roots and negligible transport to stems and leaves. Moreover, triclosan, as well as its eight metabolites, was detected and identified in celery tissues and the growth medium using 14C-labelling and LC-Q-TOF-MS analysis methods. Phase I metabolites in the growth medium were from hydroxylation, dechlorination, nitration, and nitrosylation. Phase II metabolism was the major pathway in celery tissues. Monosaccharide, disaccharide, and sulfate conjugates of triclosan were putatively identified. The results represent an important step toward a better evaluation of the behavior of triclosan in vegetables, with notable implications for environmental and human risk assessments of triclosan.


Assuntos
Apium , Triclosan , Apium/metabolismo , Humanos , Hidroponia , Triclosan/metabolismo , Verduras/metabolismo , Águas Residuárias/análise
19.
Environ Pollut ; 303: 119100, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35248618

RESUMO

Dufulin is a biologically derived antiviral agent chemically synthesized by α-phosphoramidate in sheep and is effective against viral diseases in plants such as tobacco, rice, cucumber and tomato. However, the environmental behaviors and fate of Dufulin under different cultivation systems remain unknown. This study investigates the absorption, translocation and accumulation of 14C-Dufulin stereoisomers introduced by pesticide leaf daubing and by mixing the pesticide with soil in different tissues of cherry radish. We particularly focused on whether the behaviors of Dufulin enantiomers in plants were stereoselective. In the leaf uptake experiments, S-Dufulin and R-Dufulin were transported both up and down, while more than 93% of the pesticide remained in the labeled leaves. During the radicular absorption experiments, both enantiomers of Dufulin were taken up by radish roots and moved to the upper part of the plant, while less than 0.2% Dufulin was absorbed from the soil. Hence, it was easier for Dufulin to enter plants through the leaf surface than through the roots. However, we found in this trial that the stereoisomers of Dufulin underwent nonstereoselective absorption and translocation, which implies that rac-Dufulin and its metabolites should be a major research priority. Overall, our results provide a relatively accurate prediction of the risk assessment of Dufulin, which will help guide its rational use in the environment as well as ensure eco-environmental safety and human health.


Assuntos
Praguicidas , Raphanus , Poluentes do Solo , Animais , Benzotiazóis , Compostos Organofosforados , Raphanus/metabolismo , Ovinos , Solo , Poluentes do Solo/metabolismo
20.
Sci Total Environ ; 826: 153920, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35189233

RESUMO

Information on pesticide metabolites is crucial for accurate environmental risk assessment. However, identifying the various metabolites of a novel pesticide is challenging since the potential metabolic pathways are unknown. In this study, we coupled diverse positional 14C labeling with high-resolution mass spectrometry to quantitatively and qualitatively study pesticide metabolism in rats. With the unique M/(M + 2) ratios derived from 14C, precursor compounds of metabolites could be better distinguished from impurity ions. Additionally, the use of diverse 14C labeling positions is a powerful tool to elucidate the complete metabolic fate of novel contaminants. Vanisulfane is a novel vanillin-derived antiviral agent with encouraging prospects for the efficient control of cucumber mosaic virus in China, but its metabolic pathways in mammals are still poorly understood. Thus, the metabolism of vanisulfane was studied in rats of both sexes by this strategy. The results showed that phase I and phase II metabolism occurred in both sexes. The former included mainly oxidation reactions, and the latter involved binding reactions that formed glucuronide, sulfate and amino acid conjugates. Sex-related differences were observed in the experiment, with earlier appearance of downstream metabolites and a preference for sulfate conjugate formation in males compared to females. This research facilitates the risk evaluation of vanisulfane, and offers an effective framework for screening unknown pesticide metabolic pathways, which could be applied to establish the metabolic profiles of other novel contaminants with limited information.


Assuntos
Praguicidas , Animais , Benzaldeídos , Cromatografia Líquida de Alta Pressão , Feminino , Masculino , Mamíferos , Praguicidas/análise , Ratos , Sulfatos , Espectrometria de Massas em Tandem/métodos
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