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1.
Langmuir ; 39(19): 6865-6873, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37133428

RESUMEN

Porous carbon, one of the characteristic materials for electrochemical energy storage devices, has been paid wide-ranging attention. However, balancing the reconcilable mesopore volume with a large specific surface area (SSA) was still a challenge. Herein, a dual-salt-induced activation strategy was developed to obtain a porous carbon sheet with ultrahigh SSA (3082 m2 g-1), desirable mesopore volume (0.66 cm3 g-1), nanosheet morphology, and high surface O (7.87%) and S (4.0%) content. Hence, as a supercapacitor electrode, the optimal sample possessed a high specific capacitance (351 F g-1 at 1 A g-1) and excellent rate performance (holding capacitance up to 72.2% at 50 A g-1). Furthermore, the assembled zinc-ion hybrid supercapacitor also exhibited superior reversible capacity (142.7 mAh g-1 at 0.2 A g-1) and highly stable cycling (71.2 mAh g-1 at 5 A g-1 after 10,000 cycles with retention of 98.9%). This work was delivered a new possibility for the development of coal resources for the preparation of high performance porous carbon materials.

2.
Molecules ; 28(9)2023 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-37175070

RESUMEN

The surface properties and the hierarchical pore structure of carbon materials are important for their actual application in supercapacitors. It is important to pursue an integrated approach that is both easy and cost-effective but also challenging. Herein, coal-based hierarchical porous carbon with nitrogen doping was prepared by a simple dual template strategy using coal as the carbon precursor. The hierarchical pores were controlled by incorporating different target templates. Thanks to high conductivity, large electrochemically active surface area (483 m2 g-1), hierarchical porousness with appropriate micro-/mesoporous channels, and high surface nitrogen content (5.34%), the resulting porous carbon exhibits a high specific capacitance in a three-electrode system using KOH electrolytes, reaching 302 F g-1 at 1 A g-1 and 230 F g-1 at 50 A g-1 with a retention rate of 76%. At 250 W kg-1, the symmetrical supercapacitor assembled at 6 M KOH shows a high energy density of 8.3 Wh kg-1, and the stability of the cycling is smooth. The energy density of the symmetric supercapacitor assembled under ionic liquids was further increased to 48.3 Wh kg-1 with a power output of 750 W kg-1 when the operating voltage was increased to 3 V. This work expands the application of coal-based carbon materials in capacitive energy storage.

3.
Amino Acids ; 54(8): 1215-1227, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35752997

RESUMEN

L-homoarginine (hARG) is involved in nitric oxide biosynthesis, but its role and concentration in preeclampsia (PE) have not been fully revealed. The purpose of this study was to develop and validate a feasible clinical assay to quantify serum hARG, arginine (ARG), asymmetric (ADMA) and symmetric dimethylarginines (SDMA) levels by LC-MS/MS and investigate their differences at different stages of pregnancy with or without preeclampsia. Serum samples were collected from 84 pregnant women without complications (controls), 84 with mild preeclampsia (MPE), and 81 with severe preeclampsia (SPE) at various gestation stages (before the 20th week, during the 20th-28th week or after the 28th week of gestation). No significant difference in ARG levels was observed between PE and controls at any stage (P > 0.05). The serum hARG levels and hARG/ADMA ratios of MPE before the 20th week were higher than those of controls (P < 0.001). ADMA levels of MPE were higher than those of controls during the 20th-28th week (P < 0.01). SDMA levels of SPE were higher than those of MPE (P < 0.01) and controls (P < 0.05) after the 28th week. Elevated serum hARG before the 20th week was identified as an independent predictor for PE (OR = 1.478, 95% CI 1.120-1.950). ROC curve analysis showed serum hARG before the 20th week had a good potential to predict MPE (AUC = 0.875, 95% CI 0.759-0.948). In conclusion, our study indicated that elevated serum hARG and dimethylarginine levels detected by LC-MS/MS might serve as potential biomarkers for the early prediction of PE.


Asunto(s)
Homoarginina , Preeclampsia , Arginina/análogos & derivados , Cromatografía Liquida , Femenino , Humanos , Preeclampsia/diagnóstico , Embarazo , Espectrometría de Masas en Tándem
4.
Ecotoxicol Environ Saf ; 157: 191-200, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-29621711

RESUMEN

In natural ecosystems, organisms are commonly exposed to chemical mixtures rather than individual compounds. However, environmental risk is traditionally assessed based on data of individual compounds. In the present study, we aimed to investigate the individual and combined effects of four pesticides [fenobucarb (FEN), chlorpyrifos (CPF), clothianidin (CLO), acetochlor (ACE)] and one heavy metal chromium [Cr(Ⅵ)] on the earthworm (Eisenia fetida) using avoidance behavior as an endpoint. Our results indicated that CLO had the highest toxicity to E. fetida, followed by Cr(Ⅵ), while FEN showed the least toxicity. Two mixtures of CPF+CLO and Cr(Ⅵ)+CPF+CLO+ACE exhibited synergistic effects on the earthworms. The other two quaternary mixtures of CLO+FEN+ACE+Cr(Ⅵ) and Cr(Ⅵ)+FEN+CPF+ACE at low concentrations also displayed synergistic effects on the earthworms. In contrast, the mixture of Cr(Ⅵ)+FEN had the strongest antagonistic effects on E. fetida. Besides, the quinquenary mixture of Cr(Ⅵ)+FEN+CPF+CLO+ACE also exerted antagonistic effects. These findings highlighted the importance to evaluate chemical mixtures. Moreover, our data strongly pointed out that the avoidance tests could be used to assess the effects of combined effects.


Asunto(s)
Cromo/toxicidad , Plaguicidas/toxicidad , Contaminantes del Suelo/toxicidad , Animales , Reacción de Prevención , Carbamatos/toxicidad , Cloropirifos/toxicidad , Sinergismo Farmacológico , Guanidinas/toxicidad , Metales Pesados/farmacología , Neonicotinoides/toxicidad , Oligoquetos/efectos de los fármacos , Tiazoles/toxicidad , Toluidinas/toxicidad
5.
Ecotoxicology ; 25(5): 991-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27068296

RESUMEN

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.


Asunto(s)
Atrazina/toxicidad , Herbicidas/toxicidad , Insecticidas/toxicidad , Oligoquetos/fisiología , Contaminantes del Suelo/toxicidad , Pruebas de Toxicidad Aguda , Animales , Cloropirifos/toxicidad , Imidazoles/toxicidad , Neonicotinoides , Nitrilos/toxicidad , Nitrocompuestos/toxicidad , Piretrinas/toxicidad
6.
Fish Shellfish Immunol ; 41(2): 493-500, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25304545

RESUMEN

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.


Asunto(s)
Apoptosis/efectos de los fármacos , Bencimidazoles/farmacología , Carbamatos/farmacología , Disruptores Endocrinos/farmacología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Inmunidad Innata/efectos de los fármacos , Inmunotoxinas/farmacología , Pez Cebra/genética , Análisis de Varianza , Animales , Apoptosis/genética , Cartilla de ADN/genética , Electroforesis en Gel de Agar , Regulación del Desarrollo de la Expresión Génica/inmunología , Hormonas Esteroides Gonadales/biosíntesis , Hormonas Esteroides Gonadales/metabolismo , ARN Mensajero/inmunología , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectrofotometría Ultravioleta , Hormonas Tiroideas/biosíntesis , Hormonas Tiroideas/metabolismo , Pez Cebra/embriología , Pez Cebra/inmunología
7.
J Mol Histol ; 55(4): 513-525, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38777993

RESUMEN

Environmental changes can trigger endoplasmic reticulum (ER) stress and misfolded protein accumulation, potentially leading to pre-eclampsia (PE). Amyloid-ß (Aß) is a crucial misfolded protein that can overactivate autophagy. Our study assessed the expression of Aß1-42 and autophagic activity in PE placental tissues and trophoblasts under ER stress. Placental tissues were surgically collected from normal pregnant women (NP) and pregnant women with late-onset PE (LOPE) delivering through cesarean section. The expression levels of Aß1-42 were detected in both PE and NP placental tissues, as well as in tunicamycin (TM)-induced HTR-8/SVneo cells. Autophagy-related proteins, such as Beclin-1, the ratio of LC3-II to LC3-I, ATG5, and SQSTM1/p62 in the placental tissues and HTR-8/SVneo cells were measured by Western blot. The number and morphology of autophagosomes were observed using transmission electron microscopy (TEM). Potential targets associated with the unfolded protein response (UPR) in the placental tissues of NP and PE cases were screened using PCR Arrays. The misfolded protein was significantly upregulated in the PE group. In both PE placental tissues and TM-induced HTR-8/SVneo cells, not only was Aß1-42 upregulated, but also Beclin-1, ATG5, and LC3BII/I were significantly increased, accompanied by an increase in autophagosome count, while SQSTM1/P62 was downregulated. A total of 17 differentially expressed genes (DEGs) associated with the UPR were identified, among which elevated calnexin (CANX) was validated in the placenta from both PE and TM-induced HTR-8/SVneo cells. Autophagy is significantly upregulated in PE cases due to ER stress-induced Aß1-42 accumulation, likely mediated by autophagy-related proteins involved in the UPR.


Asunto(s)
Péptidos beta-Amiloides , Autofagia , Estrés del Retículo Endoplásmico , Fragmentos de Péptidos , Preeclampsia , Trofoblastos , Tunicamicina , Humanos , Preeclampsia/metabolismo , Preeclampsia/genética , Preeclampsia/patología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Autofagia/efectos de los fármacos , Femenino , Embarazo , Péptidos beta-Amiloides/metabolismo , Línea Celular , Tunicamicina/farmacología , Tunicamicina/efectos adversos , Trofoblastos/metabolismo , Trofoblastos/efectos de los fármacos , Trofoblastos/patología , Adulto , Placenta/metabolismo , Placenta/efectos de los fármacos , Placenta/patología , Respuesta de Proteína Desplegada/efectos de los fármacos
8.
Environ Toxicol Chem ; 43(2): 429-439, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37991213

RESUMEN

Diamide insecticides are widely used in rice paddies and pose a potential threat to aquatic organisms. However, the risk research related to their application in major rice-producing areas is very limited, especially mesocosm research to simulate the impact on aquatic ecosystems of long-term exposure, as well as exposure analysis based on local models and local scenarios. To assess potential risks from a novel diamide insecticide (tetrachlorantraniliprole) to aquatic nontarget organisms in the field over long-term exposure, an outdoor mesocosm study was performed, and the environmental concentrations were predicted by the multimedia paddy-pond model (TOPRICE). The mesocosm experiment showed that tetrachlorantraniliprole mainly stayed in the aqueous phase after entering the water body. Although the chemical dissipated quickly in the aqueous phase (half-life of 0.79-1.5 days), it showed toxic effects on zooplankton communities. Cladocerans, represented by Simocephalus vetulus, were most sensitive to tetrachlorantraniliprole stress. Significant short-term toxicity to cladocerans occurred in all treatment groups, but all recovered within 8 weeks except for the highest concentration group (30.0 µg /L). Based on the ecological recovery results, 7.74 µg tetrachlorantraniliprole/L (nominal concentration, 10.0 µg /L) is suggested to be the no-observed-ecological-adverse-effect concentration (NOEAEC) for the zooplankton community. When this NOEAEC was compared with predicted environmental concentrations (PECs; the PECs in natural ponds simulated by the TOPRICE model for 148 application scheme combinations in major rice-producing areas), a relatively high risk of applying tetrachlorantraniliprole during the rice tillering stage was found. The present study makes a positive contribution to the hypothesis that the current Tier 1 approaches for global acute risk assessment have a sufficient protective effect for assessing the risk of tetrachlorantraniliprole to aquatic organisms. Also, the present results should help us to gain a fuller understanding of the ecological risk of diamide insecticides in aquatic ecosystems and their rational application schemes. Environ Toxicol Chem 2024;43:429-439. © 2023 SETAC.


Asunto(s)
Insecticidas , Oryza , Contaminantes Químicos del Agua , Animales , Insecticidas/toxicidad , Ecosistema , Zooplancton , Diamida/farmacología , Organismos Acuáticos , Contaminantes Químicos del Agua/toxicidad
9.
J Econ Entomol ; 106(1): 142-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23448026

RESUMEN

The parasitoid Trichogramma confusum Viggiani (Hymenoptera: Trichogrammatidae) is an important natural enemy of many lepidopterans throughout the world. Extensive toxicological tests have clarified the toxic effects of insecticides on trichogrammatids, but only few studies have examined these effects on T. confusum. Among the seven classes of tested chemicals, organophosphates and carbamates exhibited the highest intrinsic toxicity to the parasitoid with LC50 values ranging from 0.037 (0.030-0.046) to 0.29 (0.23-0.38) and from 0.17 (0.15-0.19) to 1.61 (1.45-1.79) mg AI L(-1), respectively. They were followed by phenylpyrazoles, avermectins, pyrethroids, and neonicotinoids, which induced variable toxicity responses with LC50 values ranging from 0.63 to 45.26, 1.06-21.73, 3.89-19.36, and 0.24-754.2 mg AI L(-1), respectively. In contrast, insect growth regulators (IGRs) showed the least toxicity to the parasitoid with LC50 values ranging from 3,907 (3,432-4,531) to 10,154 (8,857-12,143) mg AI L(-1). A risk quotient analysis indicated that neonicotinoids (except thiamethoxam), avermectins, pyrethroids, IGRs, and phenylpyrazoles are safe, but organophosphates and carbamates are slightly to moderately or dangerously toxic to T. confusum. This study provides informative data for implementing both biological and chemical control strategies in integrated pest management of lepidopterans.


Asunto(s)
Insecticidas , Avispas , Animales , Dosificación Letal Mediana , Óvulo/parasitología , Control Biológico de Vectores , Medición de Riesgo
10.
Environ Toxicol Pharmacol ; 97: 104016, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36435387

RESUMEN

Terbuthylazine is an effective and widely used s-triazine herbicide. However, limited data exists on its toxicity and bioaccumulation in earthworms (Eisenia fetida). In this study, we investigated the bioaccumulation, antioxidant enzyme activity, detoxification enzyme activity, and DNA damage in earthworms when exposed to terbuthylazine. The results indicated that terbuthylazine in soil had low bioaccumulation in earthworms and the biota-soil accumulation factors of terbuthylazine declined with an increasing soil terbuthylazine concentration. In the enzyme activity assays, the superoxide dismutase (SOD), catalase (CAT), and glutathione-S-transferase (GST) activities showed upward trends when compared with the control. The carboxylesterase (CarE) activity increased on day 21. The 8-hydroxy-2-deoxyguanosine (8-OHdG) content, a DNA damage bioindicator, was higher than that of the control on day 21. Combined with the integrated biological response index version 2 analysis, these results can provide a comprehensive evaluation of the toxicological effects that terbuthylazine has on earthworms and soil ecosystems.


Asunto(s)
Oligoquetos , Contaminantes del Suelo , Animales , Estrés Oxidativo , Oligoquetos/fisiología , Bioacumulación , Ecosistema , Catalasa/metabolismo , Antioxidantes , Triazinas/toxicidad , Suelo , Contaminantes del Suelo/toxicidad , Superóxido Dismutasa/metabolismo , Malondialdehído
12.
Chemosphere ; 227: 489-495, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31005669

RESUMEN

The contaminants, instead of single contaminants, are usually found as chemical mixtures in terrestrial environment. However, little information is now available about the joint effects of heavy metals and farm chemicals on the soil organism. Our current study aimed to assess the combined toxicity of cadmium (Cd) and four pesticides (atrazine, chlorpyrifos, lambda-cyhalothrin and abamectin) to the earthworm (Eisenia fetida) with binary, ternary, quaternary and quinquenary mixtures. Two distinct kinds of bioassay systems were applied in this study, including contact filter paper test and artificial soil test. Synergistic effects were observed from two quaternary mixtures (Cd-Atrazine-Chlorpyrifos-Lambda-cyhalothrin and Cd-Chlorpyrifos-Lambda-cyhalothrin-Abamectin) and one quinquenary mixture (Cd-Atrazine-Chlorpyrifos-Lambda-cyhalothrin-Abamectin) in both bioassay systems. Besides, two binary mixtures (Cd-Atrazine and Cd-Lambda-cyhalothrin) and three ternary mixtures (Cd-Atrazine-Chlorpyrifos, Cd-Atrazine-Lambda-cyhalothrin and Cd-Chlorpyrifos-Lambda-cyhalothrin) also exhibited synergistic effects on E. fetida by the soil toxicity test. It is more practical to evaluate the contaminant toxicities to earthworm by soil toxicity test. Therefore, the effects of chemical mixtures on soil invertebrates might be underestimated by data obtained from single toxicant. Our findings would offer a better understanding of the complex effects of chemical mixtures on non-target living creatures, and these findings provided valuable insights into the interplay of different chemicals in natural environment.


Asunto(s)
Cadmio/toxicidad , Mezclas Complejas/farmacología , Oligoquetos/efectos de los fármacos , Plaguicidas/toxicidad , Contaminantes del Suelo/toxicidad , Pruebas de Toxicidad , Animales , Insecticidas/toxicidad , Metales Pesados/toxicidad
13.
Chemosphere ; 219: 923-932, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30572241

RESUMEN

As a neurotoxic insecticide, imidacloprid (IMI) has been widely used for crop protection. However, continuous application of such pesticide in the environment may damage the non-target organisms in soil. In the present study, we aimed to investigate the effects of IMI on earthworms in terms of survival, avoidance behavior, reproduction, detoxification enzyme activity and gene expression using a systematic experimental approach. The results showed that the 14-day LC50 value of IMI was 2.26 (2.09-2.43) mg a.i. kg-1, and the 2-day AC50 value (concentration inducing an avoidance rate of 50%) of IMI was 1.34 (1.02-1.91) mg a.i. kg-1 to E. fetida. For reproduction, the 56-day EC50 value of IMI was 0.87 (0.66-1.33) mg a.i. kg-1 to E. fetida, and there was a positive correlation between the growth rate of earthworms and the number of juveniles in IMI treatments. Activities of carboxylesterase (CarE) and glutathione-S-transferases (GST) in earthworms were disturbed by IMI exposure. Moreover, effects of IMI on the CarE activity in earthworms were more severe and sensitive compared with the GST activity. The expressions of annetocin (ann) and calreticulin (crt) at the transcriptional level were decreased upon IMI exposure, reaching the lowest levels of 0.09 fold and 0.16 fold on day 7 and day 14, respectively. Transcriptionally controlled tumor protein (tctp), heat shock protein 70 (hsp70) and gst exhibited relatively obvious variations (up-regulation or down-regulation) when the exposure duration was extended. Taken together, these results comprehensively contributed to further understandings of the impacts of IMI on earthworms.


Asunto(s)
Ecotoxicología/métodos , Neonicotinoides/uso terapéutico , Nitrocompuestos/uso terapéutico , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/química , Suelo/química , Animales , Neonicotinoides/farmacología , Nitrocompuestos/farmacología
14.
Chemosphere ; 192: 14-23, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29091792

RESUMEN

Pesticides usually present in mixtures in surface waters, although they are traditionally regulated on an individual basis in aquatic ecosystems. In this study, we aimed to investigate the lethal and transcriptional responses of individual and combined pesticides (iprodione, pyrimethanil, pyraclostrobin and acetamiprid) on zebrafish (Danio rerio). Semi-static toxicity test indicated that the greatest toxicity to the four life stages (embryonic, larval, juvenile and adult stages) of D. rerio was detected from pyraclostrobin, followed by iprodione and pyrimethanil. In contrast, the lowest toxicity to the organisms was found from acetamiprid. Most of the selected pesticides exerted greater toxicities to D. rerio of embryonic stage compared with other life stages. Synergistic responses were observed from all binary mixtures of iprodione in combination with pyrimethanil or acetamiprid and ternary mixtures of iprodione+pyraclostrobin in combination with pyrimethanil or acetamiprid. The expressions of 16 genes related to cell apoptosis pathway, oxidative stress response, innate immunity and endocrine disruption at the mRNA level showed that zebrafish embryos were affected by the individual or combined pesticides. The expressions of P53, Tnf, TRß, Tsh and Cyp19a exhibited greater changes upon exposure to combined pesticides compared with individual pesticides. Taken together, increased toxicity might be triggered by the simultaneous presence of several pesticides in the aquatic environment, which seriously damaged the non-target organisms.


Asunto(s)
Ecotoxicología , Plaguicidas/toxicidad , Pez Cebra , Animales , Interacciones Farmacológicas , Disruptores Endocrinos/toxicidad , Larva/efectos de los fármacos , Pez Cebra/crecimiento & desarrollo
15.
Environ Sci Pollut Res Int ; 24(5): 4528-4536, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27943158

RESUMEN

In the present study, we evaluated the individual and mixture toxicities of imidacloprid and other four pesticides (atrazine, chlorpyrifos, butachlor, and λ-cyhalothrin) to the zebrafish (Danio rerio) larvae in order to clarify the interactive effects of pesticides on aquatic organisms. Results from the 96-h semi-static toxicity test indicated that chlorpyrifos, λ-cyhalothrin, and butachlor had the highest toxicities to D. rerio with an LC50 value ranging from 0.28 (0.13∼0.38) to 0.45 (0.31∼0.59) mg AI L-1, followed by atrazine with an LC50 value of 15.63 (10.71∼25.76) mg AI L-1, while imidacloprid exhibited the least toxicity to the organisms with an LC50 value of 143.7 (99.98∼221.6) mg AI L-1. Seven pesticide mixtures (two binary mixtures of imidacloprid + atrazine and imidacloprid + λ-cyhalothrin, two ternary mixtures of imidacloprid + atrazine + λ-cyhalothrin and imidacloprid + butachlor + λ-cyhalothrin, two quaternary mixtures of imidacloprid + atrazine + chlorpyrifos + λ-cyhalothrin and imidacloprid + chlorpyrifos + butachlor + λ-cyhalothrin, and one quinquenary mixture of imidacloprid + atrazine + chlorpyrifos + butachlor + λ-cyhalothrin) exhibited synergistic effects with equitoxic ratio and equivalent concentration on the zebrafish. Our results highlighted that the simultaneous presence of several pesticides in the aquatic environment might lead to increased toxicity, causing serious damage to the aquatic ecosystems compared with their individual toxicities. Therefore, the toxic effects of both individual pesticides and their mixtures should be incorporated into the environmental risk evaluation of pesticides.


Asunto(s)
Plaguicidas/toxicidad , Animales , Imidazoles/toxicidad , Larva/efectos de los fármacos , Neonicotinoides , Nitrocompuestos/toxicidad , Pruebas de Toxicidad , Pez Cebra
16.
Chemosphere ; 170: 61-67, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27974272

RESUMEN

Instead of individual ones, pesticides are usually detected in water environment as mixtures of contaminants. Laboratory tests were conducted in order to investigate the effects of individual and joint pesticides (phoxim, atrazine, chlorpyrifos, butachlor and λ-cyhalothrin) on zebrafish (Denio rerio). Results from 96-h semi-static toxicity test indicated that λ-cyhalothrin had the greatest toxicity to the three life stages (embryonic, larval and juvenile stages) of D. rerio with LC50 values ranging from 0.0031 (0.0017-0.0042) to 0.38 (0.21-0.53) mg a.i. L-1, followed by butachlor and chlorpyrifos with LC50 values ranging from 0.45 (0.31-0.59) to 1.93 (1.37-3.55) and from 0.28 (0.13-0.38) to 13.03 (7.54-19.71) mg a.i. L-1, respectively. In contrast, atrazine showed the least toxicity with LC50 values ranging from 6.09 (3.34-8.35) to 34.19 (24.42-51.9) mg a.i. L-1. The larval stage of D. rerio was a vulnerable period to most of the selected pesticides in the multiple life stages tested. Pesticide mixtures containing phoxim and λ-cyhalothrin exerted synergistic effects on the larvae of D. rerio. Moreover, the binary mixture of phoxim-atrazine also displayed synergistic response to zebrafish. It has been assumed that most chemicals are additive in toxicity. Therefore, it is crucial to clarify the synergistic interaction for pesticide regulators and environment managers. In the present study, our data provided a clear picture on ecological risk of these pesticide mixtures to aquatic organisms. Moreover, joint effects play a more important role than individual ones, which require more attention when defining standard for water environment quality and risk assessment protocols.


Asunto(s)
Acetanilidas/toxicidad , Atrazina/toxicidad , Cloropirifos/toxicidad , Nitrilos/toxicidad , Compuestos Organotiofosforados/toxicidad , Plaguicidas/toxicidad , Piretrinas/toxicidad , Animales , China , Monitoreo del Ambiente , Larva/efectos de los fármacos , Medición de Riesgo , Pruebas de Toxicidad , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/embriología
17.
Chemosphere ; 166: 63-71, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27684438

RESUMEN

It remains a daunting challenge to determine ecotoxicological risks of exposure to mixtures of endocrine disrupting chemicals (EDCs) in environmental toxicology. In the present study, we investigated acute and endocrine disruptive toxicities of cypermethrin (CPM), malathion (MAL), prochloraz (PRO) and their binary mixtures of MAL + CPM and MAL + PRO to the early life stages of zebrafish. In the acute lethal toxicity test, three pesticides exhibited different levels of toxicity to zebrafish larvae, and the order of toxicity was as follows: CPM > PRO > MAL. The binary mixture of MAL + CPM displayed a synergistic effect on zebrafish larvae after exposure for 24, 48, 72 and 96 h. However, binary mixture of MAL + PRO showed an antagonistic effect. To evaluate the estrogenic effect, the expression of genes in the hypothalamic-pituitary-gonadal axis was assessed after zebrafish embryos were exposed to CPM, MAL, PRO and their binary mixtures from blastula stage (1 h post-fertilization, 1 hpf) to 14 dpf (14 d post-fertilization). Our data indicated that the transcription patterns of many key genes (vtg1, vtg2, era, erß1, erß2, cyp19a1a and cyp19a1b) were affected in hatched zebrafish after exposure to CPM, MAL and PRO. Moreover, following exposure to binary mixtures of 1000 µg/L MAL +4 µg/L CPM and 1000 µg/L MAL +900 µg/L PRO, the gene expressions were significantly changed compared with the individual pesticides. Our data provided a better understanding of bidirectional interactions of toxic response induced by these pesticides.


Asunto(s)
Disruptores Endocrinos/toxicidad , Imidazoles/toxicidad , Larva/efectos de los fármacos , Malatión/toxicidad , Piretrinas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/metabolismo , Animales , Sistema Endocrino/efectos de los fármacos , Estrógenos/toxicidad , Femenino , Perfilación de la Expresión Génica , Gónadas/efectos de los fármacos , Hipotálamo/efectos de los fármacos , Masculino , Plaguicidas/toxicidad , Hipófisis/efectos de los fármacos , Factores de Tiempo , Pruebas de Toxicidad Aguda
18.
Environ Sci Pollut Res Int ; 24(9): 8722-8730, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28210953

RESUMEN

Although the earthworm Eisenia fetida has been used in many ecotoxicological studies in recent years, most of these studies have only focused on assessing the effects of individual insecticides. In the present study, we aimed to compare the individual and combined toxic effects of imidacloprid and three insecticides (phoxim, chlorpyrifos, and lambda-cyhalothrin) on E. fetida. We showed that imidacloprid had the highest intrinsic toxicity to the worms in filter paper contact test, followed by phoxim and lambda-cyhalothrin, while the least toxicity was found from chlorpyrifos. Moreover, 14-day soil toxicity test revealed that the highest toxicity was still detected for imidacloprid with an LC50 value of 2.82 (2.61∼3.17) mg a.i. kg-1 dry weight (DW), followed by chlorpyrifos with an LC50 value of 384.9 (353.5∼440.3) mg a.i. kg-1 DW. Meanwhile, a relatively less toxicity was found for lambda-cyhalothrin with an LC50 value of 560.3 (475.9∼718.5) mg a.i. kg-1 DW, while the lowest toxicity to E. fetida was observed for phoxim with an LC50 value of 901.5 (821.3∼1017) mg a.i. kg-1 DW. In addition, significant synergistic responses were found from the ternary mixture of imidacloprid-phoxim-lambda-cyhalothrin and quaternary mixture of imidacloprid-phoxim-chlorpyrifos-lambda-cyhalothrin in both bioassay systems. Therefore, our findings highlighted that the simultaneous presence of several insecticides in the soil environment might lead to increased toxicity, resulting in serious damage to the nontarget organisms compared with individual insecticides.


Asunto(s)
Ecotoxicología/métodos , Imidazoles/toxicidad , Insecticidas/toxicidad , Nitrocompuestos/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Cloropirifos/toxicidad , Sinergismo Farmacológico , Dosificación Letal Mediana , Neonicotinoides , Nitrilos/toxicidad , Compuestos Organotiofosforados/toxicidad , Piretrinas/toxicidad , Pruebas de Toxicidad
19.
Placenta ; 51: 70-75, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28292471

RESUMEN

INTRODUCTION: Pre-eclampsia (PE) is a common and severe obstetric complication. MicroRNAs (miRs) have emerged as molecules that are associated with the disease. METHODS: Quantitative reverse transcription PCR (RT-qPCR) was used for serum miR-520g characterization from 19 severe pre-eclamptic and 19 normal pregnancies. In situ hybridation was adopted to localize microRNA-520g (miR-520g). Migration and invasion of HTR-8/SVneo cells were evaluated after miR-520g mimic treatment with transwell system. MiR-520g target gene was verified in luciferase reporter system. RESULTS: The expression of serum miR-520g displayed an upward trend as pregnancies progress. At first-trimester, miR-520g in pre-eclampsia was significantly higher than that in the control, but no significant differences were found in the second and last trimesters. MiR-520g localized in cytoplasm of early trimester placental trophoblasts. The migration and invasion of HTR8/SVneo were inhibited by miR-520g mimic treatment. Matrix metalloproteinase 2 (MMP2) was verified as a direct target of miR-520g. CONCLUSIONS: Elevated maternal serum level of miR-520g level in first trimester was detected in patients with severe PE. By suppressing the migration and invasion of trophoblast via at least partial inhibition of MMP2 translation inhibition, miR-520g might play a role in the defective spiral artery remodeling, and thus contribute to pre-eclampsia pathophysiology.


Asunto(s)
Movimiento Celular/fisiología , MicroARNs/sangre , Placenta/metabolismo , Preeclampsia/metabolismo , Trofoblastos/metabolismo , Regulación hacia Arriba , Adulto , Femenino , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Placenta/patología , Preeclampsia/sangre , Preeclampsia/patología , Embarazo , Primer Trimestre del Embarazo , Trofoblastos/patología
20.
Environ Sci Pollut Res Int ; 24(4): 3483-3492, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27878481

RESUMEN

Cyazofamid, as a fungicide of the novel cyanoimidazole chemical class, has been widely used to control tomato late blight. Understanding of cyazofamid residues in environment and crops is an essential prerequisite for its risk assessment. In this study, field investigations in four typical tomato-producing areas were conducted to explore the dissipation kinetics and residues of cyazofamid and its primary metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile (CCIM) in soil and tomato. A robust method using QuEChERS coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for simultaneous analysis of cyazofamid and CCIM, with limits of quantification of 0.33 and 3.8 µg/kg, respectively. Field trials showed that the half-lives of cyazofamid were 3.6-6.9 days in soil and 12.2-18.3 days in tomato. The total residues of cyazofamid and CCIM in tomato collected at three time intervals were all below 0.5 mg/kg. Moreover, the potential risks of total residues via tomato intake to ten population subgroups were evaluated. We found that the risk quotient values were all generally low (0.13-1.3%), indicating that the recommended dose of cyazofamid on tomato will not result in a consumer exposure exceeding the toxicological reference value. Here, the results of field investigation provided important information for further understanding the behavior and risk of cyazofamid in the natural environment.


Asunto(s)
Productos Agrícolas/química , Imidazoles/análisis , Contaminantes del Suelo/análisis , Suelo/química , Solanum lycopersicum/química , Sulfonamidas/análisis , Cinética , Residuos de Plaguicidas/análisis , Medición de Riesgo , Espectrometría de Masas en Tándem/métodos
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