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1.
Mol Cell ; 83(8): 1251-1263.e6, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36996811

RESUMO

Nucleosomes drastically limit transcription factor (TF) occupancy, while pioneer transcription factors (PFs) somehow circumvent this nucleosome barrier. In this study, we compare nucleosome binding of two conserved S. cerevisiae basic helix-loop-helix (bHLH) TFs, Cbf1 and Pho4. A cryo-EM structure of Cbf1 in complex with the nucleosome reveals that the Cbf1 HLH region can electrostatically interact with exposed histone residues within a partially unwrapped nucleosome. Single-molecule fluorescence studies show that the Cbf1 HLH region facilitates efficient nucleosome invasion by slowing its dissociation rate relative to DNA through interactions with histones, whereas the Pho4 HLH region does not. In vivo studies show that this enhanced binding provided by the Cbf1 HLH region enables nucleosome invasion and ensuing repositioning. These structural, single-molecule, and in vivo studies reveal the mechanistic basis of dissociation rate compensation by PFs and how this translates to facilitating chromatin opening inside cells.


Assuntos
Nucleossomos , Proteínas de Saccharomyces cerevisiae , Nucleossomos/genética , Nucleossomos/metabolismo , Histonas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Cromatina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética
2.
Nucleic Acids Res ; 51(3): 1139-1153, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36688297

RESUMO

Transcription factors (TF) require access to target sites within nucleosomes to initiate transcription. The target site position within the nucleosome significantly influences TF occupancy, but how is not quantitatively understood. Using ensemble and single-molecule fluorescence measurements, we investigated the targeting and occupancy of the transcription factor, Gal4, at different positions within the nucleosome. We observe a dramatic decrease in TF occupancy to sites extending past 30 base pairs (bp) into the nucleosome which cannot be explained by changes in the TF dissociation rate or binding site orientation. Instead, the nucleosome unwrapping free energy landscape is the primary determinant of Gal4 occupancy by reducing the Gal4 binding rate. The unwrapping free energy landscape defines two distinct regions of accessibility and kinetics with a boundary at 30 bp into the nucleosome where the inner region is over 100-fold less accessible. The Gal4 binding rate in the inner region no longer depends on its concentration because it is limited by the nucleosome unwrapping rate, while the frequency of nucleosome rewrapping decreases because Gal4 exchanges multiple times before the nucleosome rewraps. Our findings highlight the importance of the nucleosome unwrapping free energy landscape on TF occupancy and dynamics that ultimately influences transcription initiation.


Assuntos
Nucleossomos , Fatores de Transcrição , Fatores de Transcrição/metabolismo , DNA/química , Regulação da Expressão Gênica , Sítios de Ligação
3.
Pestic Biochem Physiol ; 204: 106035, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39277362

RESUMO

The widespread application of neonicotinoid insecticides (NNIs) has attracted widespread attention to their potential ecotoxicological effects. In this study, we systematically evaluated the toxic effects of thiamethoxam (TMX) and its metabolite clothianidin (CLO) on earthworms (Eisenia fetida). Specifically, the antioxidant system responses and endogenous metabolite metabolism responses in earthworms were analyzed in the temporal dimension after 7, 14, 21 and 28 days of exposure to TMX and CLO. The results found that TMX and CLO could inhibit the growth phenotype of earthworms and cause significant changes in antioxidant system related indicators. More importantly, we found that TMX and CLO could cause significant changes in the metabolic profiles of earthworms through NMR-based metabolomics. From the changes in endogenous metabolites, the toxicity effects of TMX on earthworms gradually increases with prolonged exposure time. Differently, the toxicity effects of CLO on earthworms is significantly higher than that of TMX in the early stages of exposure. Meanwhile, these impacts will not weaken with prolonged exposure time. Furthermore, the results of KEGG enrichment pathway analysis indicated that TMX and CLO could significantly interfere with energy homeostasis, redox homeostasis, osmotic regulation, amino acid metabolism and protein synthesis in earthworms. These findings further deepen our understanding of the ecotoxicological effects of NNIs on soil organism.


Assuntos
Guanidinas , Inseticidas , Neonicotinoides , Oligoquetos , Tiametoxam , Tiazóis , Oligoquetos/efeitos dos fármacos , Oligoquetos/metabolismo , Animais , Tiametoxam/toxicidade , Neonicotinoides/toxicidade , Tiazóis/toxicidade , Guanidinas/toxicidade , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Oxazinas/toxicidade , Antioxidantes/metabolismo , Metabolômica
4.
Analyst ; 148(8): 1824-1837, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36939165

RESUMO

Hydrogen peroxide (H2O2) is involved in many important tasks in normal cell metabolism and signaling. However, abnormal levels of H2O2 are associated with the occurrence of several diseases. Therefore, it is important to develop a new method for the detection of H2O2in vivo and in vitro. A turn-off sensor, 2,2-difluoro-4,6-bis(3-methoxy-4-((4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)oxy)styryl)-2H-1,3,2-dioxaborine (DFCB), based on curcumin was developed for the detection of H2O2. The DFCB, an orange-emitting sensor, was constructed by employing 2,2-difluoro-4,6-bis(4-hydroxy-3-methoxystyryl)-2H-1,3,2-dioxaborine (DFC) as the main carrier, and 2-(4-bromomethylphenyl)-4,4,5,5-tetramethyl-1,3,2-doxaborolane as the recognition site. The recognition group on the DFCB sensor could be completely cleaved by H2O2 to generate the intermediate DFC, which would lead to a colorimetric change from bright orange to light blue accompanying by a significantly quenched fluorescence, which could be seen by the naked eye. This sensor exhibited a highly specific fluorescence response to H2O2, in preference to other relevant species, with an excellent anti-interference performance. The sensor DFCB also possessed some advantages including a wide pH response range (6-11), a broad linear range (0-300 µM), and a low detection limit (1.31 µM). The sensing mechanism of the DFCB sensor for H2O2 was verified by HRMS analysis, 1H-NMR titration and DFT calculations. In addition, the use of the DFCB sensor was compatible with the fluorescence imaging of H2O2 in living cells and zebrafish.


Assuntos
Curcumina , Animais , Colorimetria/métodos , Peróxido de Hidrogênio/análise , Peixe-Zebra , Corantes Fluorescentes/química
5.
Pestic Biochem Physiol ; 190: 105320, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36740340

RESUMO

Prothioconazole (PTC) is a widely used agricultural fungicide. In recent years, studies have confirmed that it exerts adverse effects on various species, including aquatic organisms, mammals, and reptiles. However, the toxicological effects of PTC on soil organisms are poorly understood. Here, we investigated the toxic effects, via oxidative stress and metabolic responses, of PTC on earthworms (Eisenia fetida). PTC exposure can induce significant changes in oxidative stress indicators, including the activities of superoxide dismutase (SOD) and catalase (CAT) and the content of glutathione (GSH), which in turn affect the oxidative defense system of earthworms. In addition, metabolomics revealed that PTC exposure caused significant changes in the metabolic profiles of earthworms. The relative abundances of 16 and 21 metabolites involved in amino acids, intermediates of the tricarboxylic acid (TCA) cycle and energy metabolism were significantly altered after 7 and 14 days of PTC exposure, respectively. Particularly, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that multiple different metabolic pathways could be disturbed after 7 and 14 days of PTC exposure. Importantly, these alterations in oxidative stress and metabolic responses in earthworms reveal that the effects of PTC on earthworms were time dependent, and vary with exposure time. In conclusion, this study highlights that the effects of PTC on soil organisms are of serious concern.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Oligoquetos/genética , Oligoquetos/metabolismo , Solo/química , Poluentes do Solo/análise , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Catalase/metabolismo , Mamíferos/metabolismo
6.
Analyst ; 147(10): 2080-2088, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35510666

RESUMO

A simple yet highly effective camphor-derived fluorescent probe named 3-(anthracen-9-ylmethylene)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one oxime (ATHO) was developed based on an oxime recognition receptor and anthracene fluorophore. The probe ATHO exhibited a remarkably enhanced fluorescence response to HClO (∼7.2 fold). Meanwhile, this probe exhibited a low detection limit (0.118 µM), ultrafast response time (within seconds), excellent photostability (>260 min), wide linear range (0-180 µM), low probe concentration (2 µM), and high selectivity toward HClO over various interfering species. The sensing mechanism of the probe ATHO for HClO was supported by HRMS analysis and theoretical calculations. Furthermore, the probe ATHO was utilized to quantitatively determine HClO levels in environmental water samples. Additionally, the biological imaging of the probe ATHO for exogenous and endogenous HClO was successfully demonstrated in vitro and in vivo.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Cânfora , Fluorescência , Corantes Fluorescentes/farmacologia , Ácido Hipocloroso/análise , Oximas
7.
Environ Sci Technol ; 56(24): 17890-17901, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36332113

RESUMO

Reproductive disorders are a serious public health problem worldwide. Epidemiological data suggest that exposure to environmental pollutants is associated with the onset of reproductive disorders. However, the effects in reproductive health and exact mechanism of action of representative agricultural compounds prothioconazole (PTC) and its metabolite prothioconazole-desthio (dPTC) on mammals remain unclear. Here, we studied the physiological effects of the exposure to environmentally relevant doses of PTC and dPTC in mice reproductive systems. Combining in vivo, in vitro, and in silico studies, we observed that PTC and dPTC disrupt reproductive health by inducing metabolic perturbation, induction of apoptosis, and inflammation in gonadal tissue, which are achieved via activation of the aryl hydrocarbon receptor (AhR). Convincingly, the addition of alternate-day injections of CH223191 (an AhR inhibitor) to the 30-day exposure regimen ameliorated ovarian tissue damage, as evidenced by decreased TUNEL-positive cells and partially restored the inflammation and apoptotic factor levels. This study comprehensively reports the toxic effects of low-dose PTC and dPTC in the reproductive system in vivo and identifies AhR as a potential therapeutic target for the amelioration of reproductive disorders caused by similar endocrine-disrupting chemicals.


Assuntos
Exposição Ambiental , Fungicidas Industriais , Ovário , Triazóis , Animais , Camundongos , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Fungicidas Industriais/toxicidade , Inflamação/induzido quimicamente , Receptores de Hidrocarboneto Arílico/metabolismo , Triazóis/química , Triazóis/metabolismo , Ovário/efeitos dos fármacos
8.
Macromol Rapid Commun ; 43(2): e2100608, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34699661

RESUMO

Cellulose is the most abundant natural polymer with good biodegradability and biocompatibility. In this paper, a novel fluorescent probe DAC-SD-NA for aluminum (Al3+ ) detection is successfully synthesized based on dialdehyde cellulose (DAC). DAC-SD-NA exhibited a remarkable "turn-on" fluorescence response to Al3+ in a wide pH range, and the fluorescence color of DAC-SD-NA solution turned from colorless to bright blue at the presence of Al3+ . The detection limit for Al3+ is computed to be 6.06×10-7 m. The reaction mechanism of DAC-SD-NA towards Al3+ is confirmed by Job's plot, X-ray photoelectron spectroscopy, and density functional theory (DFT) calculations. In view of DAC-SD-NA exhibited good sensitivity and selectivity, it is applied to detect Al3+ in real water. What's more, DAC-SD-NA-loaded fluorescent hydrogel can serve as a convenient tool for the detection of Al3+ .


Assuntos
Corantes Fluorescentes , Bases de Schiff , Alumínio , Celulose/análogos & derivados , Espectrometria de Fluorescência
9.
Pestic Biochem Physiol ; 187: 105194, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36127066

RESUMO

Chlorantraniliprole (CAP), a representative bisamide insecticide, is widely used in rice fields around the world, posing potential toxicity risks to aquatic organisms. In this study, we examined the effects of exposure to CAP on growth and metabolic phenotype of zebrafish (Danio rerio) and oxidative stress and apoptosis in the liver of zebrafish (Danio rerio). First, we identified that CAP had a low bioaccumulation in zebrafish. Subsequently, growth phenotype analysis revealed that CAP could significantly increase liver weight and liver index in zebrafish. In addition, we found that CAP exposure could cause significant changes in indicators of oxidative stress, resulting in a significant increase in the content of malondialdehyde (MDA), causing oxidative stress in the liver of zebrafish. Meanwhile, the expression levels of apoptosis-related genes were also significantly changed and apoptosis was promoted in the liver of zebrafish with CAP exposure. Importantly, the results of metabolomics analysis shown that CAP exposure could significantly disrupt the metabolic phenotype of zebrafish, interfering with multiple metabolic pathways, mainly including valine, leucine and isoleucine biosynthesis and degradation, alanine, aspartate and glutamate metabolism and d-glutamine and D-glutamate metabolism. Last but not least, correlation analysis identified strong links between changes in liver function involving oxidative stress and apoptosis and changes in metabolic phenotype of zebrafish following CAP exposure. In brief, these results indicate that potential environmental risks of CAP to aquatic organisms should receive more attention.


Assuntos
Inseticidas , Poluentes Químicos da Água , Alanina/metabolismo , Animais , Ácido Aspártico/genética , Ácido Aspártico/metabolismo , Ácido Aspártico/farmacologia , Ácido Glutâmico , Glutamina/genética , Glutamina/metabolismo , Glutamina/farmacologia , Inseticidas/farmacologia , Isoleucina/genética , Isoleucina/metabolismo , Isoleucina/farmacologia , Leucina , Fígado , Malondialdeído/metabolismo , Fenótipo , Valina/farmacologia , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética , ortoaminobenzoatos
10.
Pestic Biochem Physiol ; 184: 105113, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715052

RESUMO

Imazalil (IMZ) is a highly effective fungicide employed in crop production. It has been consistently detected in aquatic environments. The main environmental metabolite of IMZ is imazalil-M (IMZ-M). Limited studies have focused on the toxicity of IMZ and IMZ-M in aquatic organisms. This study systematically evaluated the developmental toxicity of IMZ and IMZ-M on zebrafish (Danio rerio) embryos and explored the potential mechanisms involved. The results showed that IMZ and IMZ-M caused developmental toxicity, characterized by decreased heart rate, hatching inhibition, and pericardial cyst in zebrafish embryos. Subsequently, acridine orange (AO) staining revealed cell apoptosis in the area around the heart regions of zebrafish larvae. Besides, the expression levels of apoptosis-related genes also varied significantly. Furthermore, 1H NMR-based metabolomics analysis showed that IMZ and IMZ-M exposure could induce metabolic profiles disorder in zebrafish larvae. Importantly, zebrafish exposure to IMZ and IMZ-M significantly affected the metabolism of branched - chain amino acids, energy, and ketone bodies, which are related to cell apoptosis. Overall, the toxicity of IMZ and IMZ-M in zebrafish embryos and larvae was characterized, suggesting a theoretical basis for the potential environmental risks of IMZ and its metabolite IMZ-M on non-target organisms.


Assuntos
Doenças Metabólicas , Poluentes Químicos da Água , Animais , Apoptose , Embrião não Mamífero , Imidazóis/toxicidade , Larva , Doenças Metabólicas/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética
11.
Pestic Biochem Physiol ; 180: 104983, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34955176

RESUMO

Prothioconazole (PTA), a new triazole fungicide, has been widely used worldwide. A recent study has confirmed that PTA and its main metabolite prothioconazole-desthio (dPTA) interfere with the liver metabolism in reptiles. However, little is known about liver toxicity of these two pollutants in mammals. Here, female mice were orally exposed to PTA (1.5 mg/kg body weight/day) and dPTA (1.5 mg/kg body weight/day) for 30 days. Additionally, growth phenotype and indexes related to serum and liver function were examined. Using metabolomics and gene expression analysis, PTA- and dPTA-induced hepatotoxicity was studied to clarify its potential underlying mechanism of action. Together, the results indicated that PTA and dPTA exposure caused changes in growth phenotypes, including elevated blood glucose levels, triglyceride accumulation, and damage of liver function. Additionally, exposure to PTA and dPTA caused changes in genes and metabolites related to glycolipid metabolism in female mice, thereby interfering with the pyruvate metabolism and glycolysis/gluconeogenesis pathways, ultimately leading to hepatic metabolism disorders. In particular, the effect of dPTA on hepatotoxicity has been proven to be more significant than that of PTA. Thus, these findings help us understand the underlying mechanism of action of PTA and dPTA exposure-induced hepatotoxicity in mammals and possibly humans.


Assuntos
Fungicidas Industriais , Triazóis , Animais , Fungicidas Industriais/toxicidade , Glicolipídeos , Fígado , Camundongos , Triazóis/toxicidade
12.
Anal Bioanal Chem ; 413(25): 6267-6277, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34355255

RESUMO

In this work, a novel fluorescent probe CBO was synthesized for detecting Fe2+ using the natural monoterpenketone camphor as the starting material. The probe CBO displayed turn-on fluorescence to Fe2+ accompanied by the solution change from colorless to green. As expected, there was an excellent linear relationship between the fluorescence intensity of probe CBO and the concentration of Fe2+ (0-20 µM), and the detection limit was as low as 1.56×10-8 M. In particular, CBO could selectively sense Fe2+ more than other analytes (Fe3+ included) through the N-oxide strategy, and quickly responded to Fe2+ (60 s) over a wide pH (4-14) range. Additionally, based on the rapid fluorescence response of CBO to Fe2+, a simple test strip-based detector was designed for boosting practical applicability. The probe CBO had been successfully applied to the fluorescence imaging of Fe2+ in onion cells and living zebrafish. The probe CBO was a powerful tool of detecting Fe2+ level in organisms, which was of significance to understand the role of Fe2+ in Fe2+-related physical processes and diseases.


Assuntos
Cânfora/química , Corantes Fluorescentes/química , Ferro/química , Animais , Concentração de Íons de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Cebolas/citologia , Sensibilidade e Especificidade , Peixe-Zebra
13.
Pestic Biochem Physiol ; 168: 104619, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32711760

RESUMO

Imazethapyr (IMZT) is a typical chiral pesticide with two enantiomers with the R-IMZT having the main herbicidal activity. However, the enantioselectivity of the effects of IMZT enantiomers on human and animals is still unclear. In this study, a nuclear magnetic resonance (NMR)-based metabolomics method and determination of oxidative stress were used to evaluate the enantioselectivity of IMZT enantiomers in mice. The results showed that the R-IMZT caused larger disturbances of endogenous metabolites and the S-IMZT had stronger interferences to oxidation defense system. The significantly perturbed metabolic pathways in mice exposed to the R-enantiomer were the valine, leucine and isoleucine biosynthesis pathway as well as the phenylalanine, tyrosine and tryptophan biosynthesis pathway. However, exposure of mice to the S-enantiomer did not significantly affect the metabolic pathways, but exposure led to an increase of catalase (CAT) activity and an increase in malondialdehyde (MDA) content in the liver. These results indicate that we need to conduct a more comprehensive assessment of the health risks of pesticide monomers in the future. In a word, these results provide more evidence for assessing the differences in health risks of IMZT enantiomers to mammals as well as provide more references for the promotion and use of pesticide monomers in the future.


Assuntos
Herbicidas , Ácidos Nicotínicos , Animais , Humanos , Metabolômica , Camundongos , Estereoisomerismo
14.
Environ Res ; 173: 189-198, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30921577

RESUMO

Bisphenol S (BPS), a substitute of bisphenol A (BPA), is widely used for manufacturing different polymers. Due to its wide range of applications, BPS has been frequently detected in the foodstuffs, environment and human blood and excreta. In this study, we examined the effects of the perinatal exposure to BPS on obesity development using 1H NMR based on metabolomics strategy combined with gene expression analysis in male mouse offspring at a dosage of 100 ng/g bw/day. We found that perinatal exposure to BPS significantly increased the body weight, the weights of liver and epididymal white adipose tissue (epiWAT), serum alanine aminotransferase (ALT) activity, and the contents of triglyceride (TG) and cholesterol (T-Cho) in the liver. Histopathological analysis showed that lipids were accumulated significantly in liver tissues and epiWAT with BPS exposure. Furthermore, expressions of genes involved in the inflammatory pathways were significantly increased in liver tissues and epiWAT. Meanwhile, serum metabolomics study showed significant changes in the contents of metabolites associated with lipid and glucose metabolism. Correspondingly, the relative expression levels of genes involved in lipid and glucose metabolism were significantly changed in the liver tissue and epiWAT of male mouse offspring. In conclusion, these results showed that perinatal exposure to BPS may increase the risk of obesity by interfering with lipid and glucose metabolism in male mouse offspring. The potential health risks of BPS in the human required further detailed studies evaluating.


Assuntos
Compostos Benzidrílicos , Obesidade , Fenóis/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Sulfonas/toxicidade , Animais , Feminino , Glucose , Humanos , Lipídeos , Masculino , Camundongos , Gravidez
15.
Environ Monit Assess ; 188(5): 266, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27048491

RESUMO

Nowadays, there is an urgent need for the investigation of the field dissipation and assessment of the preharvest interval for trichlorfon residues on rice. To protect consumers from potential health risks, this study can provide references for the safe application of trichlorfon in the rice fields. Results of the field dissipation study showed that the dissipation dynamic equations of trichlorfon were based on the first-order reaction dynamic equations and that the dissipation rates vary among rice plant, brown rice, rice bran, soil, and water. The 2-year field trials conducted in Yangzhou and Xiaogan suggested the interval of each application for trichlorfon on rice to be at least 7 days when 80 % trichlorfon SP was sprayed with a dose ranges between 80 and 160 a.i g/667 m(2). Additionally, the preharvest interval of the last application should be at least 15 days to ensure the amounts of residues below the maximum residue limits of trichlorfon on brown rice (0.1 mg/kg).


Assuntos
Monitoramento Ambiental , Inseticidas/análise , Modelos Químicos , Resíduos de Praguicidas/análise , Triclorfon/análise , Agricultura , Cinética , Oryza/química , Solo/química , Triclorfon/química
16.
Int J Biol Macromol ; 266(Pt 1): 131209, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565364

RESUMO

Mercury ion (Hg2+) is one of harmful heavy metal ions that can accumulate inside the human organism and cause some health problems. In the article, a highly effective fluorescent probe named EC-T-PCBM was prepared by grafting flavonol derivatives onto ethyl cellulose for the specific recognition of Hg2+. EC-T-PCBM exhibited a remarkable fluorescence light-up response toward Hg2+ with excellent sensitivity. EC-T-PCBM possessed several prominent sensing properties for Hg2+, such as low detection limit (43.9 nM), short response time (5 min), and wide detection pH range (6-9). The response mechanism of EC-T-PCBM to Hg2+ has been verified through 1H NMR titration and DFT computation. Additionally, EC-T-PCBM not only can be used for accurately determining trace amount of Hg2+ in actual environmental water samples, but also can serve as a portable and rapid device by loading it on test strips for sensitive and selective visualization of Hg2+. More importantly, the confocal fluorescence imaging of onion cells suggested the favorable cell membrane permeability of EC-T-PCBM and its prominent ability to continuously monitor the enrichment from Hg2+ within fresh plant tissues.


Assuntos
Celulose , Flavonóis , Corantes Fluorescentes , Mercúrio , Mercúrio/análise , Celulose/química , Celulose/análogos & derivados , Corantes Fluorescentes/química , Flavonóis/química , Flavonóis/análise , Espectrometria de Fluorescência/métodos , Limite de Detecção , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise , Cebolas/química , Imagem Óptica/métodos
17.
Sci Total Environ ; 923: 171494, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38453077

RESUMO

Pesticides and microplastics are common pollutants in soil environments, adversely affecting soil organisms. However, the combined toxicological effects of aged microplastics and pesticides on soil organisms are still unclear. In this study, we systematically studied the toxicological effects of azoxystrobin and four different aged polyethylene (PE) microplastics on earthworms (Eisenia fetida). The purpose was to evaluate the effects of aging microplastics on the toxicity of microplastics-pesticides combinations on earthworms. The results showed that different-aged PE microplastics promoted azoxystrobin accumulation in earthworms. Meanwhile, combined exposure to azoxystrobin and aged PE microplastics decreased the body weight of earthworms. Besides, both single and combined exposure to azoxystrobin and aged PE microplastics could lead to oxidative damage in earthworms. Further studies revealed that azoxystrobin and aged PE microplastics damage the intestinal structure and function of earthworms. Additionally, the combination of different aged PE microplastics and azoxystrobin was more toxic on earthworms than single exposures. The PE microplastics subjected to mechanical wear, ultraviolet radiation, and acid aging exhibited the strongest toxicity enhancement effects on earthworms. This high toxicity may be related to the modification of PE microplastics caused by aging. In summary, these results demonstrated the enhancing effects of aged PE microplastics on the toxicity of pesticides to earthworms. More importantly, aged PE microplastics exhibited stronger toxicity-enhancing effects in the early exposure stages. This study provides important data supporting the impact of different aged PE microplastics on the environmental risks of pesticides.


Assuntos
Oligoquetos , Praguicidas , Pirimidinas , Poluentes do Solo , Estrobilurinas , Animais , Microplásticos/toxicidade , Plásticos/toxicidade , Polietileno/toxicidade , Raios Ultravioleta , Poluentes do Solo/análise , Estresse Oxidativo , Solo/química
18.
Talanta ; 277: 126355, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38838563

RESUMO

Acute liver injury (ALI) is a frequent and devastating liver disease that has been made more prevalent by the excessive use of chemicals, drugs, and alcohol in modern life. Hypochlorous acid (HClO), an important biomarker of oxidative stress originating mainly from the mitochondria, has been shown to be intimately connected to the development and course of ALI. Herein, a novel BODIPY-based NIR ratiometric fluorescent probe Mito-BS was constructed for the specific recognition of mitochondrial HClO. The probe Mito-BS can rapidly respond to HClO within 20 s with a ratiometric fluorescence response (from 680 nm to 645 nm), 24-fold fluorescence intensity ratio enhancement (I645/I680), a wide pH adaptation range (5-9) and the low detection limit (31 nM). The probe Mito-BS has been effectively applied to visualize endogenous and exogenous HClO fluctuations in living zebrafish and cells based on its low cytotoxicity and prominent mitochondria-targeting ability. Furthermore, the fluorescent probe Mito-BS makes it possible to achieve the non-invasive in-situ diagnosis of ALI through in mice, and provides a feasible strategy for early diagnosis and drug therapy of ALI and its complications.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Mitocôndrias , Peixe-Zebra , Ácido Hipocloroso/análise , Ácido Hipocloroso/metabolismo , Animais , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Camundongos , Mitocôndrias/metabolismo , Modelos Animais de Doenças , Humanos , Compostos de Boro/química , Imagem Óptica , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico por imagem
19.
Int J Biol Macromol ; 276(Pt 2): 133936, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39032908

RESUMO

Palladium ion (Pd2+) plays an important role in our daily life, but poses a great threat to the environment and human health. Thus, it is desirable to exploit a rapid and sensitive approach to realize the detection of Pd2+. In this study, a cellulose acetate-based macromolecular fluorescent probe CA-NA-PA was successfully prepared for tracking amounts of Pd2+. CA-NA-PA showed an obvious "on-off" fluorescence response to Pd2+, accompanied by the fluorescence color changed from bright yellow to colorless. CA-NA-PA had some outstanding detection performances such as low detection limit (26 nM), extremely short response time (1 min), good selectivity and anti-interference ability. Based on the advantages of probe mentioned above, CA-NA-PA could realize recognition of Pd2+ concentration in environmental water and soil samples. What's more, the probe CA-NA-PA was applied to image Pd2+ in zebrafish as well as in live onion tissue due to the good biocompatibility and cell membrane permeability of cellulose, suggesting its wide application prospect in biosystems.


Assuntos
Celulose , Corantes Fluorescentes , Paládio , Peixe-Zebra , Celulose/química , Celulose/análogos & derivados , Paládio/química , Corantes Fluorescentes/química , Animais , Íons , Cebolas/química
20.
Carbohydr Polym ; 328: 121726, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38220346

RESUMO

Fluorescent sensors available for metal ions detection have been extensively developed in recent years. However, developing an ultrasensitive fluorescent sensor for highly selectively detecting Al3+ based on cellulose remains a challenge. In this study, an ethylcellulose-based flavonol fluorescent sensor named EC-BHA was synthesized by the esterification of ethylcellulose (EC) with a new flavonol derivative 4-(2-(2,3-bis(ethoxymeothy)phenyl)-3-hydroxy-4-oxo-4-H-chromen-7-yl) benzoic acid (BHA). The fluorescence intensity of EC-BHA exhibited a 180-fold increase at 490 nm after binding with Al3+ and provided an ultralow detection limit of 13.0 nM. The sensor showed some exceptional sensing properties including a broad pH range (4-10), large Stokes shifts (190 nm), and a short response time (3 min). This sensor was successfully applied for determining trace Al3+ in food samples as well as in plant tissue. Moreover, the electrostatic spun film EBP was fabricated by blending EC-BHA with PS (polystyrene) via electrostatic spinning technique and utilized for selective detection of Al3+ as soon as possible.


Assuntos
Alumínio , Corantes Fluorescentes , Corantes Fluorescentes/química , Alumínio/química , Celulose/química , Flavonóis
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