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1.
Arq. Inst. Biol. (Online) ; 89: e00342020, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1416869

RESUMO

The identification of the application stage and correct dose of 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide is important so that wheat is not harmed. In view of this, the objective of this study was to evaluate the effect of 2,4-D doses applied at different development stages of wheat crop. The experiment was conducted in a randomized block design, arranged in a 4 × 5 factorial scheme, with four replications. In factor A, the application stages (before tillering, tillering, first node and booting) were allocated and the doses of 2,4-D (0, 349, 698, 1047 and 1396 g.ha­1) were allocated in factor B. The variables evaluated were phytotoxicity at 7, 14, 21, 28 and 35 days after application of the treatments (DAT), photosynthetic activity, CO2 internal concentration, stomatal conductance, efficient water use and carboxylation efficiency. The number of spikes·m­2, spike length and number of full and sterile grains were determined in the preharvest. Thousand grain mass, grain yield and hectoliter weight were determined after harvest. The results demonstrate that the herbicide caused phytotoxicity to wheat, being greater in increasing doses and mainly before tillering, causing grain sterility and decreased productivity. The other yield components did not present difference when increasing the dose and application in different stages as well as the physiological variables. The increase of the 2,4-D doses applied before tillering and in the booting stage caused linear decrease in wheat grain yield.


Assuntos
Triticum/crescimento & desenvolvimento , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Herbicidas/análise , Herbicidas/toxicidade , Estágios do Ciclo de Vida
2.
Food Chem Toxicol ; 157: 112601, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34626751

RESUMO

The current generation of carcinogenicity tests is often insufficient to predict cancer outcomes from pesticide exposures. In order to facilitate health risk assessment, The International Agency for Research on Cancer identified 10 key characteristics which are commonly exhibited by human carcinogens. The ToxTracker panel of six validated GFP-based mouse embryonic stem reporter cell lines is designed to measure a number of these carcinogenic properties namely DNA damage, oxidative stress and the unfolded protein response. Here we present an evaluation of the carcinogenic potential of the herbicides glyphosate, 2,4-D and dicamba either alone or in combination, using the ToxTracker assay system. The pesticide 2,4-D was found to be a strong inducer of oxidative stress and an unfolded protein response. Dicamba induced a mild oxidative stress response, whilst glyphosate did not elicit a positive outcome in any of the assays. The results from a mixture of the three herbicides was primarily an oxidative stress response, which was most likely due to 2,4-D with dicamba or glyphosate only playing a minor role. These findings provide initial information regarding the risk assessment of carcinogenic effects arising from exposure to a mixture of these herbicides.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Dano ao DNA/efeitos dos fármacos , Dicamba/toxicidade , Glicina/análogos & derivados , Herbicidas/toxicidade , Testes de Mutagenicidade , Estresse Oxidativo/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Animais , Dicamba/administração & dosagem , Relação Dose-Resposta a Droga , Glicina/administração & dosagem , Glicina/toxicidade , Herbicidas/administração & dosagem , Humanos , Camundongos , Testes de Mutagenicidade/métodos , Ratos , Glifosato
3.
J Biochem Mol Toxicol ; 35(12): e22912, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34463001

RESUMO

2,4-Dichlorophenoxyacetic acid (2,4-D), a member of the phenoxy family of herbicides is commonly used in agriculture for controlling broadleaf weeds but its uncontrolled and incoherent use has been linked to incidences of lung toxicity. The present study aimed to understand the molecular mechanisms behind the 2,4-D alone or in combination with endotoxin (lipopolysaccharide [LPS]) induced pulmonary toxicity. Blood and lung samples were collected from Swiss albino mice (n = 48) following chronic exposure to high (37 mg/kg; 1/10th of LD50 ) and low (18.5 mg/kg; 1/20th of LD50 ) doses of 2,4-D alone or in combination with endotoxin (80 µg/animal). Transcriptome analysis revealed Wnt Canonical signaling as one of the top dysregulated pathways in mice lung following exposure to 2,4-D with and without endotoxin (LPS) co-exposure. Global view of differentially expressed genes showed increased messenger RNA expression of Axin2 by 0.26, 2.58, 3.14, 2.59, and 2.97 folds following exposure to LPS, high dose alone or in combination with LPS and low dose alone or in combination with LPS, respectively. The microarray data were validated using quantitative polymerase chain reaction and immunohistochemistry. Furthermore, the plasma concentration of Axin2 was elevated in the high dose group as revealed by Sandwich ELISA. The data taken together suggest a role of Axin2 to activate the Canonical Wnt signaling pathway in 2,4-D and or endotoxin-induced lung damage in mice.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Proteína Axina/metabolismo , Endotoxinas/toxicidade , Herbicidas/toxicidade , Pulmão/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Animais , Proteína Axina/sangue , Regulação para Baixo/efeitos dos fármacos , Endotoxinas/administração & dosagem , Perfilação da Expressão Gênica , Herbicidas/administração & dosagem , Pulmão/metabolismo , Masculino , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Regulação para Cima/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
4.
Sci Rep ; 9(1): 16695, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723191

RESUMO

Common waterhemp emerges throughout the crop growing season in the Midwestern United States, and as a result, the seedlings are exposed to a wide range of temperature regimes. Typically, 2,4-D is used in the Midwest to control winter annual broad-leaf weeds before planting soybean and in an early post-emergence application in corn and sorghum; however, the evolution of 2,4-D-resistant common waterhemp in several Midwestern states may limit the use of 2.4-D for controlling this problem weed. Moreover, temperature is one of the crucial factors affecting weed control efficacy of 2,4-D. This research investigated the effect of temperature on efficacy of 2,4-D to control 2,4-D susceptible (WHS) and -resistant (WHR) common waterhemp. Do se-response of WHS and WHR to 2,4-D was assessed at two temperature regimes, high (HT; 34/20 °C, d/n) and low (LT; 24/10 °C, d/n). Whole plant dose response study indicated an increased level of 2,4-D resistance in WHR at HT compared to LT. Additional investigation of the physiological mechanism of this response indicated that both WHS and WHR common waterhemp plants rapidly metabolized 14C 2,4-D at HT compared to LT. In conclusion, a rapid metabolism of 2,4-D conferred increased level of resistance to 2,4-D in WHR at HT. Therefore, application of 2,4-D when temperatures are cooler can improve control of 2,4-D resistant common waterhemp.


Assuntos
Ácido 2,4-Diclorofenoxiacético/metabolismo , Amaranthus/metabolismo , Evolução Biológica , Resistência a Herbicidas , Herbicidas/metabolismo , Plantas Daninhas/metabolismo , Controle de Plantas Daninhas/métodos , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Amaranthus/efeitos dos fármacos , Herbicidas/administração & dosagem , Meio-Oeste dos Estados Unidos , Plantas Daninhas/efeitos dos fármacos , Temperatura
5.
J Environ Sci Health B ; 54(10): 803-809, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31264502

RESUMO

The aim of this study was to evaluate the effect of time of the day and their associated climatic conditions on spray deposition of two 2,4-D formulations, as well as the influence on weed control. The experiment was installed in the field in complete randomized design. Treatments were arranged in factorial design 8 × 2, with 20 repetitions. First factor corresponded to different application time (1:00, 4:00, 7:00, 10:00, 13:00, 16:00, 19:00, and 22:00) with their respective climatic conditions. The second factor consisted of two formulations of 2,4-D applied at 776 g a.e. ha-1 (2,4-D amine and 2,4-D choline salt with Colex-D™ Technology) + glyphosate (816 g a.e. ha-1). There was more spray deposition when 2,4-D choline formulation was used, and such differences were more evident for applications performed under adverse climatic conditions. More spray deposition was found in applications performed at times of day with more favorable temperature and humidity of the air conditions. Only the initial control of the evaluated species was affected by the time of application.


Assuntos
Ácido 2,4-Diclorofenoxiacético , Herbicidas , Plantas Daninhas , Controle de Plantas Daninhas/métodos , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Bidens , Brasil , Cenchrus , Commelina , Glicina/administração & dosagem , Glicina/análogos & derivados , Herbicidas/administração & dosagem , Umidade , Distribuição Aleatória , Temperatura , Tempo (Meteorologia) , Glifosato
6.
Sci Rep ; 9(1): 4363, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30867497

RESUMO

The gut microbiota critically confers various health benefits, whereas environmental chemicals can affect its constitution and functionality thereby increasing disease risk. In the present study, we aim to evaluate the toxic effects of a wildly-used herbicide 2,4-D (2,4-dichlorophenoxyacetic acid) on the gut microbiome and host using an occupationally relevant dose. A mouse model was used combined with metagenomic sequencing and metabolomic profiling to examine the alterations induced by subchronic low-dose 2,4-D exposure in fecal and plasma samples. The metagenomics results revealed a distinct gut microbial community with profound changes in diverse microbial pathways including urea degradation, amino acid and carbohydrate metabolism in 2,4-D-treated mice. Moreover, the metabolomics results revealed that the metabolic profiles in treatment group were differentiated from control group in both fecal and plasma samples. Toxic effects on the host of 2,4-D at an occupationally relevant dose were observed indicated by decreased acylcarnitine levels in plasma. These findings indicated that 2,4-D can cause toxicity and substantially impact the gut microbiome in mice at occupationally relevant doses, inferring that the relationship between environmental contaminants and microbiota is largely underestimated calling for more comprehensive consideration of the toxicity of occupational exposures.


Assuntos
Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Carnitina/análogos & derivados , Microbioma Gastrointestinal/efeitos dos fármacos , Herbicidas/administração & dosagem , Ácido 2,4-Diclorofenoxiacético/efeitos adversos , Animais , Carnitina/sangue , Biologia Computacional , Exposição Ambiental , Herbicidas/efeitos adversos , Metaboloma/efeitos dos fármacos , Metabolômica/métodos , Metagenoma , Camundongos
7.
Pak J Biol Sci ; 22(11): 518-526, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31930830

RESUMO

BACKGROUND AND OBJECTIVE: Sipahutar pineapple (Ananas comosus L.) is a indigenous of pineapple grown in Sipahutar district, North Sumatra, Indonesia. Propagation of Sipahutar pineapple that being done traditionally is less effective, because the number of seeds that produced is very limited and requires a long time. Propagation through in vitro culture is an alternative solution to solve this problem. It is necessary to add plant growth regulator (PGR) to stimulate callus formation in Sipahutar pineapple explants (Ananas comosus L.). Callus induction of pineapple from Sipahutar was carried out by PGR treatment on MS medium. The purpose of this study was to determine the effect MS medium treatment with added dichlorophenoxyacetic acid (2,4-D) and benzyl amino purin (BAP) PGR on Sipahutar pineapple callus formation (Ananas comosus L.) with light and dark treatment. MATERIALS AND METHODS: This callus induction research used a completely randomized design (CRD) with 2 factors, the first factor was treatment 2,4-D (0, 1, 2) ppm. The second factor is BAP (0, 0.5, 1) ppm. RESULTS: Nine combinations of treatments are obtained. Each combination of treatments is treated in both light and dark conditions. The parameters of this study were the percentage (%) of explants that formed callus, the time of callus formed, callus texture, callus biomass, callus surface height and callus surface area. Data were analyzed with two-way ANOVA, followed by Duncan Multiple Rate Test (DMRT). CONCLUSION: The study showed that the interaction between 2,4-D and BAP significantly affected the time of callus formed but 2,4-D and BAP did not significantly affect callus biomass, callus surface height and callus surface area. All explants can form callus, except explants without the addition of 2,4-D and BAP. The callus formed on 10 days after induction (DAI) and 12 DAI with the treatment of light and dark. The color of the produced callus were white, yellowish white, greenish white, brown, brownish yellow, brownish white, brownish green, yellowish green and greenish white. The callus formed is generally compact textures, except for explants which by giving 1 ppm 2,4-D produce friable callus.


Assuntos
Ananas/crescimento & desenvolvimento , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Ananas/efeitos dos fármacos , Compostos de Benzil/administração & dosagem , Biomassa , Produção Agrícola/métodos , Meios de Cultura , Indonésia , Reguladores de Crescimento de Plantas/farmacologia , Plantas Comestíveis/efeitos dos fármacos , Plantas Comestíveis/crescimento & desenvolvimento , Purinas/administração & dosagem
8.
Cell Mol Biol (Noisy-le-grand) ; 64(7): 92-96, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29974852

RESUMO

Arctium lappa L. (Burdock) is an important plant with various pharmacological effects. According to the importance of this plant, optimization of its tissue culture will lead to more investigation and application of it. The aim of this study was to develop protocols for callus induction and shoot regeneration of A.  lappa. In order to optimize of tissue culture in A. lappa, callus induction, indirect regeneration and direct regeneration were carried out in factorial experiment based on Completely Randomized Designs (CRDs). Hypocotyl and cotyledon were cultured on the Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of 2,4-Dichlorophenoxyacetic acid (2,4-D) and 6-Benzylaminopurine (BAP) for callus induction. In indirect regeneration experiment various levels of BAP and α-Naphthaleneacetic acid (NAA) and two types of explants (calli derived from cotyledon and hypocotyl) were investigated. In direct regeneration section, various levels of BAP plus 2 mg/l NAA and different explants (cotyledon, hypocotyl and bud) were compared. In both cotyledon and hypocotyl, the maximum callus induction was observed on a media containing 2 mg/l 2,4-D plus 1 mg/l BAP (100% and 76.19% respectively). The highest percentage of indirect regeneration (65%) was observed at 1 mg/l BAP plus 0.5 mg/l NAA on calli from hypocotyl. The highest percentage of direct regeneration (90.33) was observed in hypocotyl with a lateral bud explant on MS medium supplemented with 0.5 mg/l BAP plus 2 mg/l NAA. In this study, optimization of tissue culture protocol for A. lappa was carried out as a research technique, as well as technique for further exploitation of this plant.


Assuntos
Arctium/fisiologia , Diferenciação Celular/efeitos dos fármacos , Organogênese Vegetal/efeitos dos fármacos , Plantas Medicinais/fisiologia , Regeneração/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Arctium/efeitos dos fármacos , Compostos de Benzil/administração & dosagem , Calo Ósseo/efeitos dos fármacos , Cotilédone/efeitos dos fármacos , Meios de Cultura/farmacologia , Hipocótilo/efeitos dos fármacos , Ácidos Naftalenoacéticos/administração & dosagem , Reguladores de Crescimento de Plantas/farmacologia , Plantas Medicinais/efeitos dos fármacos , Purinas/administração & dosagem , Técnicas de Cultura de Tecidos
9.
J Environ Sci Health B ; 51(12): 888-893, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27768529

RESUMO

The objective of this study was to evaluate the effects of nozzle types and 2,4-D formulations on spray deposition on different targets. Two field experiments were carried out in a completely randomized design, and treatments were arranged in a factorial scheme. Species in experiment 1 were Sumatran fleabane (Conyza sumatrensis) and Brazil pusley (Richardia brasiliensis) and in experiment 2 were soybeans (Glycine max) and Benghal dayflower (Commelina benghalensis). For both experiments, the first factor corresponded to spray nozzles with different settings (AD 110.015 - 61 and 105 L ha-1; AD 015-D - 75 and 146 L ha-1; XR 110.0202 - 200 L ha-1; and ADIA-D 110.02 - 208 L ha-1) and the second factor consisted of two formulations of 2,4-D (amine and choline). The formulation of 2,4-D choline has contained Colex-D™ Technology. Similar or higher spray deposition was observed on the leaves and artificial targets when using 2,4-D choline as compared to the 2,4-D amine formulation, and these differences in deposition were more evident for nozzles applying lower spray volumes. Deposition was more affected by nozzle type when amine formulation was used, compared to choline formulation.


Assuntos
Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Agricultura/instrumentação , Agricultura/métodos , Brasil , Commelina , Conyza/efeitos dos fármacos , Dimetilaminas/administração & dosagem , Desenho de Equipamento , Plantas Daninhas/efeitos dos fármacos , Distribuição Aleatória , Glycine max
10.
Arch Toxicol ; 90(12): 3061-3071, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26838045

RESUMO

It was reported that 2,4-dichlorophenoxyacetic acid (2,4-D), a commonly used herbicide and a possible endocrine disruptor, can disturb spermatogenesis, but the precise mechanism is not understood. Since 2,4-D is a weak peroxisome proliferator in hepatocytes and peroxisome proliferator-activated receptor α (PPARα) is also expressed in Leydig cells, this study aimed to investigate the link between PPARα and 2,4-D-mediated testicular dysfunction. 2,4-D (130 mg/kg/day) was administered to wild-type and Ppara-null mice for 2 weeks, and the alterations in testis and testosterone/cholesterol metabolism in Leydig cells were examined. Treatment with 2,4-D markedly decreased testicular testosterone in wild-type mice, leading to degeneration of spermatocytes and Sertoli cells. The 2,4-D decreased cholesterol levels in Leydig cells of wild-type mice through down-regulating the expression of 3-hydroxy-3-methylglutaryl coenzyme A synthase 1 and reductase, involved in de novo cholesterogenesis. However, the mRNAs encoding the important proteins involved in testosterone synthesis were unchanged by 2,4-D except for CYP17A1, indicating that exhausted cholesterol levels in the cells is a main reason for reduced testicular testosterone. Additionally, pregnancy rate and the number of pups between 2,4-D-treated wild-type male mice and untreated female mice were significantly lower compared with those between untreated couples. These phenomena were not observed in 2,4-D-treated Ppara-null males. Collectively, these results suggest a critical role for PPARα in 2,4-D-induced testicular toxicity due to disruption of cholesterol/testosterone homeostasis in Leydig cells. This study yields novel insights into the possible mechanism of testicular dysfunction and male infertility caused by 2,4-D.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Disruptores Endócrinos/toxicidade , Herbicidas/toxicidade , Infertilidade Masculina/induzido quimicamente , Células Intersticiais do Testículo/efeitos dos fármacos , PPAR alfa/metabolismo , Testosterona/metabolismo , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Animais , Colesterol/química , Relação Dose-Resposta a Droga , Disruptores Endócrinos/administração & dosagem , Repressão Enzimática/efeitos dos fármacos , Herbicidas/administração & dosagem , Hidroximetilglutaril-CoA Redutases/química , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Hidroximetilglutaril-CoA Sintase/antagonistas & inibidores , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/patologia , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Masculino , Camundongos da Linhagem 129 , Camundongos Knockout , PPAR alfa/genética , Proliferadores de Peroxissomos/administração & dosagem , Proliferadores de Peroxissomos/toxicidade , Distribuição Aleatória , Epitélio Seminífero/efeitos dos fármacos , Epitélio Seminífero/metabolismo , Epitélio Seminífero/patologia , Epitélio Seminífero/fisiopatologia , Espermatogênese/efeitos dos fármacos
11.
Biomed Res Int ; 2014: 620434, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995315

RESUMO

We synthesized twenty thiazolidin-4-one derivatives, which were then characterized by standard chromatographic and spectroscopic methods. From the in vitro glucose uptake assay, two compounds behaved as insulin sensitizers, where they enhanced glucose uptake in isolated rat diaphragm. In high-carbohydrate diet-induced insulin resistant mice, these two thiazolidin-4-ones attenuated hyperglycemia, hyperinsulinemia, hypertriglyceridemia, hypercholesterolemia, and glucose intolerance. They raised the plasma leptin but did not reverse the diabetes-induced hypoadiponectinemia. Additionally, compound 3a reduced adiposity. The test compounds were also able to reverse the disturbed liver antioxidant milieu. To conclude, these two novel thiazolidin-4-ones modulated multiple mechanisms involved in metabolic disorders, reversing insulin resistance and thus preventing the development of type-2 diabetes.


Assuntos
Ácido 2,4-Diclorofenoxiacético/análogos & derivados , Transtornos do Metabolismo de Glucose/tratamento farmacológico , Resistência à Insulina , Tiazolidinas/química , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Ácido 2,4-Diclorofenoxiacético/síntese química , Ácido 2,4-Diclorofenoxiacético/química , Animais , Antioxidantes/metabolismo , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Ácido Clofíbrico/administração & dosagem , Ácido Clofíbrico/síntese química , Ácido Clofíbrico/química , Transtornos do Metabolismo de Glucose/sangue , Transtornos do Metabolismo de Glucose/patologia , Humanos , Insulina/sangue , Leptina/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Ratos , Tiazolidinas/administração & dosagem , Tiazolidinas/síntese química
12.
ScientificWorldJournal ; 2014: 947167, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25009832

RESUMO

Prior studies have shown that applications of the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D) to the foliage of potato plants can reduce common scab. Here field and glasshouse trials suggest that 2,4-D foliar treatments may also reduce the biologically distinct tuber disease, powdery scab. Significant correlations between suppression of common and powdery scab from the field trials suggested an interaction between the two diseases or possible additional broad spectrum mechanisms of enhanced defence against pathogen invasion provided by 2,4-D treatment.


Assuntos
Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Solanum tuberosum/microbiologia , Solanum tuberosum/parasitologia , Solanum tuberosum/efeitos dos fármacos , Streptomyces/efeitos dos fármacos
13.
Ceska Slov Farm ; 63(1): 17-21, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24568333

RESUMO

Effect of exogenously applied jasmonic acid (JA) in combination with calcium and verapamil (a calcium channels blocker) on the production of flavonoids and isoflavonoids in suspension cultures of Trifolium pratense L. was investigated. The culture was cultivated in Gamborg medium with an addition of 2 mg.l(-1) of 2,4-dichlorophenoxyacetic acid and 2 mg.l(-1) of 6-benzylaminopurine, at the temperature of 25 °C, 16-hr light/8-hr dark period. The best effect of jasmonic acid on the production of flavonoids and isoflavonoids was manifested after a 24-hour application of the 50 µmol.l(-1) concentration. The maximum production of JA-induced suspension culture was observed when cells were treated with a high level of calcium (10 mmol.l(-1)). The addition of all concentrations of verapamil to JA-induced suspension culture decreased production of flavonoids and isoflavonoids.


Assuntos
Ciclopentanos/administração & dosagem , Flavonoides/isolamento & purificação , Oxilipinas/administração & dosagem , Trifolium/química , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Compostos de Benzil , Técnicas de Cultura de Células , Cinetina/administração & dosagem , Purinas
14.
Rev Biol Trop ; 61(3): 1095-107, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24027910

RESUMO

J. curcas has been studied in different countries and some interesting agronomic, pharmacological and industrial properties have been reported. More recently, it has been considered an important alternative source for biofuel production. The objective of this study was to establish a long-term method for the maintenance of calli and cell suspension cultures of the local species J. curcas and J. gossypifolia, in order to allow future studies for novel compounds with pharmaceutical or industrial applications. For this, friable calli were successfully induced from hypocotyl segments of.. curcas and J. gossypifolia that were cultured in semisolid MS media supplemented with 1.5 mg/L, and 0.5 mg/L of 2,4-D, respectively. Cell suspension cultures of J. curcas were established using 1 g of 35 and 60-day calli, in 50 mL of liquid MS media supplied with 1.5 mg/L of 2,4-D; sucrose and maltose were additionally evaluated as carbon sources. After 35 days, cell suspension cultures initiated with 35-day calli, showed greater cell growth with a maximum biomass of 194.9 g/L fresh weight, 6.59 g/L dry weight and 17.3% packed volume. The exponential phase ended at day 35 for cultures initiated with 35-day calli, and at day 21 for cultures initiated with 60-day calli. Higher biomass production was obtained with sucrose. Cell cultures were established with 35-day calli in MS media with the same 2,4-D concentration used for calli induction and 30g/L sucrose. This medium was considered optimum for the maintenance and growth of cell suspensions for both species, with sub-cultures every 20 days. The biotechnological potential for the production of bioactive compounds in these species for pharmacological, agricultural and industrial applications is being evaluated.


Assuntos
Técnicas de Cultura de Células/métodos , Jatropha/crescimento & desenvolvimento , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Biomassa , Jatropha/efeitos dos fármacos , Maltose/administração & dosagem , Sacarose/administração & dosagem , Suspensões , Fatores de Tempo
15.
Plant Foods Hum Nutr ; 68(3): 293-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23828497

RESUMO

Black carrots contain anthocyanins possessing enhanced physiological activities. Explants of young black carrot shoots were cultured in Murashige and Skoog (MS) medium for callus initiation and were transferred to new MS medium supplemented with four different combinations of 2,4-dichlorophenoxyacetic acid and kinetin. Subsequently, the lyophilized calli and black carrot harvested from fields were subjected to ultrasound extraction with ethanol at a ratio of 1:15 (w:v). Obtained extracts were applied to various human cancer cell lines including MCF-7 SK-BR-3 and MDA-MB-231 (human breast adenocarcinomas), HT-29 (human colon adenocarcinoma), PC-3 (human prostate adenocarcinoma), Neuro 2A (Musmusculus neuroblastoma) cancer cell lines and VERO (African green monkey kidney) normal cell line by MTT assay. The highest cytotoxic activity was achieved against Neuro-2A cell lines exhibiting viability of 38-46% at 6.25 µg/ml concentration for all calli and natural extracts. However, a significantly high IC50 value of 170.13 µg/ml was attained in normal cell line VERO indicating that its natural counterpart is an ideal candidate for treatment of brain cancer without causing negative effects to normal healthy cells.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Daucus carota/química , Neoplasias/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Animais , Antocianinas/análise , Neoplasias da Mama , Linhagem Celular Tumoral , Chlorocebus aethiops , Meios de Cultura , Daucus carota/crescimento & desenvolvimento , Feminino , Células HT29 , Humanos , Cinetina/administração & dosagem , Células MCF-7 , Masculino , Camundongos , Neuroblastoma , Neoplasias da Próstata , Técnicas de Cultura de Tecidos , Células Vero
16.
Food Chem Toxicol ; 59: 356-61, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23806294

RESUMO

This study aims to assess effects of 96 h goldfish exposure to 1, 10 and 100 mg/L of the herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), on metabolic indices and free radical process markers in white muscle of a commercial fish, the goldfish Carassius auratus L. Most oxidative stress markers and antioxidant enzymes were not affected at 2,4-D fish treatment. 2,4-D fish exposure induced the elevated levels of total (by 46% and 40%) and reduced (by 77% and 73%) glutathione in muscles of goldfish of 10 mg/L 2,4-D and recovery (after 100 mg/L of 2,4-D exposure) groups, respectively. However, in muscles of 100 mg/L 2,4-D exposed goldfish these parameters were depleted (by 47% and 64%). None of investigated parameters of protein and carbohydrate metabolisms changed in white muscles of 2,4-D exposed fish, with exception of lactate dehydrogenase activity, which was slightly (by 11-15%) elevated in muscles of goldfish exposed to 10-100 mg/L of 2,4-D, but also recovered. Thus, the short term exposure of goldfish to the selected concentrations of 2,4-D does not substantially affect their white muscle, suggesting the absence of any effect under the environmentally relevant concentrations.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Radicais Livres/metabolismo , Carpa Dourada/metabolismo , Herbicidas/toxicidade , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Metabolismo dos Carboidratos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Proteínas de Peixes/agonistas , Proteínas de Peixes/metabolismo , Glutationa/metabolismo , Carpa Dourada/sangue , Herbicidas/administração & dosagem , Cinética , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fibras Musculares de Contração Rápida/metabolismo , Oxirredução , Oxirredutases/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Poluentes Químicos da Água/administração & dosagem
17.
Biotech Histochem ; 88(3-4): 202-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23398176

RESUMO

We studied the eco-toxic and carcinogenic effects of a commonly used 2,4-D acid iso-octylester herbicide on rat liver and pancreas. The rats in Group 1 were fed a standard feed and the rats in Group 2 were fed with standard feed to which was added 200 mg/kg/day 2,4-D acid iso-octylester for 16 weeks. Azaserine, 30 mg/kg/body weight, was injected into rats of Groups 3 and 4 to investigate the effects of 2,4-D acid iso-octylester on the development of neoplasms. After feeding the rats with neoplasms in Group 4 with food including 200 mg/kg/day 2,4-D acid iso-octylester for 16 weeks, an autopsy was carried out on all animals. We found that 2,4-D acid iso-octylester caused the formation of atypical cell foci (ACF) in the pancreata and livers of rats. ACF that were formed experimentally by exposure to azaserine had increased diameter, volume and number of atypical cell foci/mm(2) and mm(3) after exposure to 2,4-D acid iso-octylester. Our observations indicated that this herbicide potentially is a cancer initiator.


Assuntos
Ácido 2,4-Diclorofenoxiacético/análogos & derivados , Herbicidas/toxicidade , Fígado/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Ácido 2,4-Diclorofenoxiacético/toxicidade , Animais , Azasserina/administração & dosagem , Azasserina/toxicidade , Carcinógenos/administração & dosagem , Carcinógenos/toxicidade , Cocarcinogênese , Herbicidas/administração & dosagem , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Pâncreas/patologia , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/patologia , Ratos , Ratos Wistar , Vesículas Secretórias/efeitos dos fármacos , Vesículas Secretórias/patologia
18.
Regul Toxicol Pharmacol ; 64(3): 481-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23017741

RESUMO

Conventional chemical exposure assessment relies upon measurements or estimates of chemical concentrations in environmental media, food, or products, in combination with assumptions regarding contact rates, in order to estimate external doses (ppm in air) or intake rates of chemicals (e.g., mg/kg/day ingested). A risk assessment is conducted by comparing these external or intake dose estimates to appropriate (e.g., route-specific) exposure guidance values (e.g., Reference Dose or Reference Concentration) to assess whether exposures are exceeding levels of concern. Human biomonitoring, in which concentrations of chemicals are measured in blood or urine, is being increasingly used as an alternative or complementary exposure assessment. The Biomonitoring Equivalent, which is the translation of a Reference Dose to an equivalent concentration of a compound in blood or urine, provides a parallel means to interpret biomonitoring data in order to assess whether chemical-specific exposures exceed levels of concern. This manuscript presents a side-by-side comparison of the two approaches for assessing exposures and risks for a case study compound, 2,4-dichlorophenoxyacetic acid (2,4-D). The findings from this case study indicate that the external dose-based assessments result in estimates of exposure and resulting hazard quotients that are consistently several-fold higher than those based on biomonitoring data. These comparisons support a conclusion that exposure assessments conducted as part of the registration process for 2,4-D incorporate sufficiently conservative assumptions.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Herbicidas/toxicidade , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Animais , Feminino , Herbicidas/administração & dosagem , Humanos , Masculino , Ratos , Valores de Referência , Medição de Risco
19.
J Agric Food Chem ; 60(26): 6463-70, 2012 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-22686323

RESUMO

The sustained release and reduced leaching of herbicides is expected for enhancing their efficacy and minimizing their pollution. For this purpose, the rice straw biochar made at a relatively low temperature (350 °C) (RS350) was used simultaneously as the carrier for incorporating herbicides besides as the soil amendment. In this way, the sustained release of herbicides acetochlor and 2,4-D was obtained in the release experiments, due to the high and reversible sorption by RS350 biochar. Besides, the RS350 biochar significantly reduced the leached amount of herbicides by 25.4%-40.7% for acetochlor, and by 30.2%-45.5% for 2,4-D, depending on the depth (50 or 100 mm) of biochar-amended soil horizon. The high retention of both herbicides in the biochar-amended topsoil makes it possible to extend their efficacy. The results suggest a potential way of using low temperature biochars to reduce the leaching of herbicides without impacting their efficacy.


Assuntos
Carvão Vegetal , Herbicidas/administração & dosagem , Oryza , Solo/análise , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Ácido 2,4-Diclorofenoxiacético/química , Adsorção , Carvão Vegetal/química , Preparações de Ação Retardada , Recuperação e Remediação Ambiental/métodos , Herbicidas/química , Toluidinas/administração & dosagem , Toluidinas/química
20.
Environ Toxicol ; 27(3): 137-45, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20607813

RESUMO

The 2,4-Dichlorophenoxyacetic acid (2,4-D) was used in agriculture as an herbicide in many countries including Tunisia. The aim of this study was to evaluate the effects of 2,4-D on liver function of adult rats and their progeny. Female Wistar rats were divided into two groups: the controls and the treated rats which received 600 ppm of 2,4-D in their drinking water from the 14th day of pregnancy until day 14 after delivery. In 2,4-D group, a significant decrease in body weight of pups was noted, when compared to controls. Liver antioxidant enzyme activities, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) decreased, while malondialdehyde (MDA) levels increased in dams and pups. Moreover, plasma aminotransferases (ALT, AST), gamma glutamil transpeptidase (GGT), lactate dehydrogenase (LDH), bilirubin and albumin levels were increased significantly. The biochemical modifications were correlated with histopathological studies. We concluded that 2,4-D induced hepatotoxicity in adult and suckling rats.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Herbicidas/toxicidade , Fígado/efeitos dos fármacos , Estresse Oxidativo , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Alanina Transaminase/sangue , Animais , Catalase/metabolismo , Água Potável/química , Feminino , Glutationa Peroxidase/metabolismo , Herbicidas/administração & dosagem , L-Lactato Desidrogenase/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Malondialdeído/metabolismo , Gravidez , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Tunísia
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