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1.
Plant Dis ; 103(10): 2536-2540, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31424998

RESUMO

Fusarium head blight, also called scab, is caused by Fusarium graminearum and is one of the most important destructive diseases of wheat. The frequency of carbendazim resistance in 1,132 isolates of F. graminearum recovered from fields in different regions of Henan Province in 2016, 2017, and 2018 was determined. A total of 31 F. graminearum isolates resistant to carbendazim were detected, including 30 moderately resistant isolates and one highly resistant isolate. The frequency of resistance of F. graminearum isolates to carbendazim was 2.7%. The range of effective concentration (EC50) values of 1,101 sensitive isolates and 30 moderately resistant isolates was 0.08 to 0.98 µg ml-1 and 2.73 to 13.28 µg ml-1, respectively. The mean ± SD EC50 value was 0.55 ± 0.13 µg ml-1 and 5.61 ± 2.58 µg ml-1, respectively. The EC50 value of the highly resistant isolate was 21.12 µg ml-1. Point mutation types of the carbendazim-resistant isolates were characterized by cloning the ß2-tubulin gene of 31 resistant isolates. Three point mutation types at amino acids F167Y, E198Q, and E198L in the ß2-tubulin gene of resistant isolates were identified. Among 31 resistant isolates, the frequency of point mutation types in F167Y, E198Q, and E198L of the ß2-tubulin gene was 71.0, 25.8, and 3.2%, respectively. The data indicate that F. graminearum has developed resistance to carbendazim in Henan Province, and single point mutations at amino acid F167Y were the predominant type of mutation detected.


Assuntos
Benzimidazóis , Carbamatos , Farmacorresistência Fúngica , Fusarium , Triticum , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Farmacorresistência Fúngica/genética , Fungicidas Industriais , Fusarium/efeitos dos fármacos , Fusarium/genética , Genes de Plantas/genética , Mutação Puntual , Triticum/microbiologia , Tubulina (Proteína)/genética
2.
BMC Plant Biol ; 19(1): 371, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438856

RESUMO

BACKGROUND: Propamocarb (PM) is one of the main pesticides used for controlling cucumber downy mildew. However, due to its volatility and internal absorption, PM can easily form pesticide residues on cucumber fruits that seriously endanger human health and pollute the environment. The breeding of new cucumber varieties with a low abundance of PM residues via genetic methods constitutes an effective strategy for reducing pesticide residues and improving cucumber safety and quality. To help elucidate the molecular mechanism resulting in a low PM residue abundance in cucumber, we used the cucumber cultivar 'D0351' (which has the lowest PM residue content) as the test material and identified genes related to low PM residue abundance through high-throughput tag-sequencing (Tag-Seq). RESULTS: CsMAPEG was constitutively expressed and showed both varietal and organizational differences. This gene was strongly expressed in 'D0351'. The expression levels of CsMAPEG in different cucumber tissues under PM stress were as follows: fruit>leaf>stem>root. CsMAPEG can respond to salicylic acid (SA), gibberellin (GA) and Corynespora cassiicola Wei (Cor) stress and thus plays an important regulatory role in plant responses to abiotic and biological stresses. The PM residue abundance in the fruits of CsMAPEG-overexpressing plants was lower than those found in antisense CsMAPEG plants and wild-type plants at all tested time points. The results revealed that CsMAPEG played a positive role in reducing the PM residue abundance. A CsMAPEG sense construct increased the contents of SOD, POD and GST in cucumber fruits, enhanced the degradation and metabolism of PM in cucumber, and thus effectively reduced the pesticide residue abundance in cucumber fruits. CONCLUSIONS: The expression patterns of CsMAPEG in cucumber cultivars with high and low pesticide residue abundances and a transgenic verification analysis showed that CsMAPEG can actively respond to PM stress and effectively reduce the PM residue abundance in cucumber fruits. The results of this study will help researchers further elucidate the mechanism responsible for a low PM residue abundance in cucumber and lay a foundation for the breeding of new agricultural cucumber varieties with low pesticide residue abundances.


Assuntos
Carbamatos/farmacologia , Cucumis sativus/genética , Fungicidas Industriais/farmacologia , Genes de Plantas , Resíduos de Praguicidas , Clonagem Molecular , Cucumis sativus/efeitos dos fármacos , Cucumis sativus/enzimologia , Cucumis sativus/fisiologia , Perfilação da Expressão Gênica , Vetores Genéticos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transformação Genética
3.
Pestic Biochem Physiol ; 158: 101-111, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378344

RESUMO

Standard chemical insecticides present mainly neurotoxic effects and are becoming less and less effective due to insects developing resistance to them. One of the innovative strategies to control insects pests is to find a way to increase the sensitivity of the target sites in the insect nervous system to the applied insecticides. In the presented research, we proposed menthol, a component of essential oils, as a factor increasing the effectiveness of bendiocarb, a carbamate insecticide. The aim of our study was to evaluate the potentiation of the bendiocarb effect by menthol. In toxicity tests performed on Periplaneta americana, menthol (0.1 µM) accelerated the lethal effect of bendiocarb, primarily in its low concentrations (lower than 0.05 mM). In the presence of menthol (1 and 0.1 µM), the ability of insects to turn back from its dorsal to the normal ventral side was significantly lower than with bendiocarb (1 µM) alone. We also evaluated the effectiveness of chemicals on the activity of the ventral nerve cord of the cockroach. In this preparation, bendiocarb (1 µM and higher concentrations) caused an irregular, spontaneous bursts of action potentials. The total nerve activity (including the response to stimulation and spontaneous firing) was much higher when bendiocarb was applied in the presence of menthol (1 µM). The effect of menthol was similar to the octopamine effect and was abolished by phentolamine, the octopamine receptor antagonist. Our results clearly indicated a strengthening effect of menthol on bendiocarb effectiveness; potentiation occurred through octopamine receptors activation.


Assuntos
Carbamatos/farmacologia , Baratas/efeitos dos fármacos , Inseticidas/farmacologia , Mentol/farmacologia , Óleos Voláteis/química , Fenilcarbamatos/farmacologia , Acetilcolinesterase/metabolismo , Animais , Interações de Medicamentos , Resistência a Inseticidas
4.
Pestic Biochem Physiol ; 158: 128-134, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378348

RESUMO

Indoleacetic acid (IAA)-carbendazim was synthesized to assess whether this conjugate could retain the fungicidal activity of carbendazim and gain root-inducing properties upon the addition of an indoleacetic acid group. An indoor virulence test demonstrated that the conjugate retained the fungicidal activity of carbendazim towards Cylindrocladium parasiticum. The conjugate was detected in roots after soaking Ricinus communis L. leaves into a solution of the IAA-carbendazim, which confirmed its phloem mobility. The activities of the cellulase, polygalacturonase and xylanase produced by Cylindrocladium parasiticum treated with different concentrations of the conjugate were determined, and the peak activities appeared at 72 h or 96 h. More importantly, the conjugate showed the ability to promote root growth. These results revealed that indoleacetic acid-carbendazim may be useful in preventing Cylindrocladium parasiticum and other diseases.


Assuntos
Ascomicetos/efeitos dos fármacos , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Fungicidas Industriais/farmacologia , Ácidos Indolacéticos/farmacologia , Celulase/metabolismo , Floema/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Poligalacturonase/metabolismo , Ricinus/efeitos dos fármacos
5.
Pestic Biochem Physiol ; 158: 61-68, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378362

RESUMO

Insecticide resistance in house fly populations is a major problem faced by livestock producers worldwide. A survey of insecticide resistance levels and pyrethroid resistance allele frequencies in the United States was conducted in 2008-09, but little is known about how resistance levels have changed over the last 10 years. In addition, new target-site pyrethroid resistance alleles that confer high levels of resistance have been recently identified in the voltage-sensitive sodium channel, and their frequencies in field populations are unknown. Our aim in this study was to reassess the resistance status of house flies from select locations in the United States by examining resistance levels against commonly used insecticides and frequencies of known resistance alleles. House flies were collected from animal production facilities in five different states between 2016 and 2018. Resistance levels to three insecticides (permethrin, tetrachlorvinphos, and methomyl), representing three classes of insecticides (pyrethroids, organophosphates and carbamates) varied geographically and were lowest in the population collected from New Mexico, intermediate in the population collected from Utah, and greatest in the population from Kansas. The recently identified 1B pyrethroid resistance allele increased dramatically in frequency compared to previous reports, most notably in populations from Kansas and Maryland, indicating that it may already be widespread around the United States. Based on comparison with historical data, the population collected from Kansas represents one of the most highly permethrin resistant populations ever sampled. If the alleles responsible for this level of resistance spread, pyrethroids may be of limited use for house fly control in the United States in the near future.


Assuntos
Moscas Domésticas/efeitos dos fármacos , Inseticidas/farmacologia , Animais , Carbamatos/farmacologia , Moscas Domésticas/genética , Resistência a Inseticidas/genética , Organofosfatos/farmacologia , Permetrina/farmacologia , Estados Unidos
6.
Plant Dis ; 103(9): 2385-2391, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31313639

RESUMO

Stimulatory effects of low doses of fungicides on the virulence of phytopathogens have profound implications for applications of fungicides. The present study demonstrated that carbendazim sprayed at 0.001 to 0.03 µg/ml had stimulatory effects on the virulence of mycelia of Botrytis cinerea, and the maximum percent stimulations were 15.5 and 21.4% for isolates HB459 and HB536, respectively. Potato dextrose agar (PDA) amended with carbendazim at 0.01, 0.02, and 0.05 µg/ml inhibited mycelial growth of isolate HB536 by 0.8, 10.0, and 30.6%, respectively. However, after the inhibited mycelia were inoculated on cucumber leaves, virulence increased by 10.1, 12.9, and 10.8%, respectively. With respect to sclerotial production, carbendazim at 0.005 and 0.02 µg/ml in PDA significantly (P < 0.05) increased, while at 0.1 µg/ml significantly (P < 0.05) reduced the sclerotial number and weight of both isolates compared with nontreated controls. Conidia germination percentages slightly yet statistically significantly (P < 0.05) increased after being inoculated on PDA amended with carbendazim at 0.001 and 0.005 µg/ml. Carbendazim at 0.001∼0.02 µg/ml, either sprayed on cucumber leaves or cosuspended with conidia, exerted significantly (P < 0.05) stimulatory effects on the virulence of B. cinerea conidia. Mechanism studies showed that sublethal doses of carbendazim did not increase the expression levels of pathogenicity-related pectin methylesterase gene Bcpme1, endopolygalacturonase gene Bcpg2, cutinase gene CutA, xylanase gene Xyn11A, or NADPH oxidase gene BcnoxA.


Assuntos
Benzimidazóis , Botrytis , Carbamatos , Doenças das Plantas , Virulência , Benzimidazóis/farmacologia , Botrytis/efeitos dos fármacos , Carbamatos/farmacologia , Virulência/efeitos dos fármacos
7.
Pestic Biochem Physiol ; 157: 26-32, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153474

RESUMO

Nitenpyram is very effective in controlling Nilaparvata lugens (brown planthopper, BPH), and its resistance has been reported in field populations; however, the resistance mechanism remains unclear. In the present study, cross-resistance and resistance mechanisms in nitenpyram-resistant BPH were investigated. A resistant strain (NR) with a high resistance level (164.18-fold) to nitenpyram was evolved through successive selection for 42 generations from a laboratory susceptible strain (NS). The bioassay results showed that the NR exhibited cross-resistance to imidacloprid (37.46-fold), thiamethoxam (71.66-fold), clothianidin (149.17-fold), dinotefuran (98.13-fold), sulfoxaflor (47.24-fold), cycloxaprid (9.33-fold), etofenprox (10.51-fold) and isoprocarb (9.97-fold) but not to triflumezopyrim, chlorpyrifos and buprofezin. The NR showed a 3.21-fold increase in cytochrome P450 monooxygenase (P450) activity compared to that in the NS, while resistance was also synergized (4.03-fold) with the inhibitor piperonyl butoxide (PBO), suggesting a role of P450. Furthermore, the mRNA expression levels of cytochrome P450 (CYP) genes by quantitative real-time PCR results indicated that twelve P450 genes were significantly overexpressed in the NR strain, especially CYP6ER1 (203.22-fold). RNA interference (RNAi) suppression of CYP6ER1 through injection of dsCYP6ER1 led to significant susceptibility in the NR strain. The current study expands our understanding of the nitenpyram resistance mechanism in N. lugens, provides an important reference for integrated pest management (IPM), and enriches the theoretical system of insect toxicology.


Assuntos
Hemípteros/efeitos dos fármacos , Neonicotinoides/farmacologia , Animais , Carbamatos/farmacologia , Guanidinas/farmacologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Nitrocompostos/farmacologia , Piretrinas/farmacologia , Piridinas/farmacologia , Pirimidinonas/farmacologia , Interferência de RNA , Tiazóis/farmacologia
8.
Plant Dis ; 103(8): 2076-2082, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31194616

RESUMO

Stem-end rot caused by Botryodiplodia theobromae is a destructive disease of mango. B. theobromae field isolates resistant to carbendazim (MBC) were collected in Hainan Province, China. In this study, the characteristics of these field isolates with resistance to MBC were investigated. The resistance of B. theobromae isolates to MBC was stably inherited. Both the MBC-resistant and MBC-sensitive isolates had similar mycelial growth rates, pathogenicity, sensitivity to high glucose, glycerol content, and peroxidase activity. Compared with MBC-sensitive isolates, MBC-resistant isolates were more sensitive to low temperature and had a significant decrease in sensitivity to high NaCl and a significant increase in catalase (CAT) and glutathione S-transferase (GST) activities. After MBC treatment, the cell membrane permeability of the sensitive isolates was markedly increased compared with that of the resistant isolates. Analysis of the ß-tubulin gene sequence revealed point mutations resulting in substitutions at codon 198 from glutamic acid (GAG) to alanine (GCG) in moderately resistant isolates, and at codon 200 from phenylalanine (TTC) to tyrosine (TAC) in highly resistant isolates. These ß-tubulin gene mutations were consistently associated with MBC resistance. Overall, we infer that the altered cell membrane permeability and the increase in CAT and GST activities of the resistant isolates are linked to MBC resistance.


Assuntos
Ascomicetos , Benzimidazóis , Carbamatos , Farmacorresistência Fúngica , Fungicidas Industriais , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Ascomicetos/genética , Ascomicetos/metabolismo , Benzimidazóis/farmacologia , Carbamatos/farmacologia , China , Farmacorresistência Fúngica/genética , Fungicidas Industriais/farmacologia , Genes Fúngicos/genética
9.
J Enzyme Inhib Med Chem ; 34(1): 1078-1082, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31124389

RESUMO

3-Methylpentyl(4-sulphamoylphenyl)carbamate (MSPC) came as the most potent compound out of a new series of carbamates composed of phenyl-ethanol or branched aliphatic alcohols, and 4-benzenesulphonamide-carbamic acid. In this study, the anticonvulsant activity and pharmacokinetics (PKs) of MSPC-two individual enantiomers were comparatively analysed in rats as well as their carbonic anhydrase (CA) inhibition. The anticonvulsant activity of MSPC enantiomers was evaluated at the rat-maximal electroshock (MES) test, and their CA inhibition evaluated. (R)-MSPC had a 29% higher clearance and consequently, a lower plasma exposure area under the curve (AUC) than (S)-MSPC and racemic-MSPC. Nevertheless, (R)-MSPC had a better brain permeability than its (S)-enantiomer with brain-to-plasma-(AUC)-ratio (BPR) of 2.07 ((R)-enantiomer), 1.85 (racemate), and 0.79 ((S)-enantiomer). As a whole body (in vivo) pharmacodynamic (PD) measure, MSPC-anticonvulsant maximal electroshock seizure (MES) activity was less enantioselective than MSPC-CA inhibition. The lack of significant differences between racemic-MSPC and its individual enantiomers suggest that their anticonvulsant activity might be due to multiple mechanisms of action.


Assuntos
Anticonvulsivantes/farmacologia , Carbamatos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Fármacos do Sistema Nervoso Central/farmacologia , Sistema Nervoso Central/efeitos dos fármacos , Animais , Anticonvulsivantes/síntese química , Anticonvulsivantes/química , Carbamatos/síntese química , Carbamatos/química , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Anidrases Carbônicas/metabolismo , Sistema Nervoso Central/metabolismo , Fármacos do Sistema Nervoso Central/síntese química , Fármacos do Sistema Nervoso Central/química , Relação Dose-Resposta a Droga , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade
10.
Plant Dis ; 103(7): 1515-1524, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31059385

RESUMO

Powdery mildew, caused by the fungus Podosphaera xanthii, is one of the most economically important diseases affecting cucurbit crops in Spain. Currently, chemical control offers the most efficient management of the disease; however, P. xanthii isolates resistant to multiple classes of site-specific fungicides have been reported in the Spanish cucurbit powdery mildew population. In previous studies, resistance to the fungicides known as methyl benzimidazole carbamates (MBCs) was found to be caused by the amino acid substitution E198A on ß-tubulin. To detect MBC-resistant isolates in a faster, more efficient, and more specific way than the traditional methods used to date, a loop-mediated isothermal amplification (LAMP) system was developed. In this study, three sets of LAMP primers were designed. One set was designed for the detection of the wild-type allele and two sets were designed for the E198A amino acid change. Positive results were only obtained with both mutant sets; however, LAMP reaction conditions were only optimized with primer set 2, which was selected for optimal detection of the E198A amino acid change in P. xanthii-resistant isolates, along with the optimal temperature and duration parameters of 65°C for 75 min, respectively. The hydroxynaphthol blue (HNB) metal indicator was used for quick visualization of results through the color change from violet to sky blue when the amplification was positive. HNB was added before the amplification to avoid opening the lids, thus decreasing the probability of contamination. To confirm that the amplified product corresponded to the ß-tubulin gene, the LAMP product was digested with the enzyme LweI and sequenced. Our results show that the LAMP technique is a specific and reproducible method that could be used for monitoring MBC resistance of P. xanthii directly in the field.


Assuntos
Ascomicetos , Farmacorresistência Fúngica , Doenças das Plantas , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Ascomicetos/fisiologia , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Técnicas de Amplificação de Ácido Nucleico , Espanha
11.
Int J Mol Sci ; 20(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934674

RESUMO

A series of new benzene-based derivatives was designed, synthesized and comprehensively characterized. All of the tested compounds were evaluated for their in vitro ability to potentially inhibit the acetyl- and butyrylcholinesterase enzymes. The selectivity index of individual molecules to cholinesterases was also determined. Generally, the inhibitory potency was stronger against butyryl- compared to acetylcholinesterase; however, some of the compounds showed a promising inhibition of both enzymes. In fact, two compounds (23, benzyl ethyl(1-oxo-1-phenylpropan-2-yl)carbamate and 28, benzyl (1-(3-chlorophenyl)-1-oxopropan-2-yl) (methyl)carbamate) had a very high selectivity index, while the second one (28) reached the lowest inhibitory concentration IC50 value, which corresponds quite well with galanthamine. Moreover, comparative receptor-independent and receptor-dependent structure⁻activity studies were conducted to explain the observed variations in inhibiting the potential of the investigated carbamate series. The principal objective of the ligand-based study was to comparatively analyze the molecular surface to gain insight into the electronic and/or steric factors that govern the ability to inhibit enzyme activities. The spatial distribution of potentially important steric and electrostatic factors was determined using the probability-guided pharmacophore mapping procedure, which is based on the iterative variable elimination method. Additionally, planar and spatial maps of the host⁻target interactions were created for all of the active compounds and compared with the drug molecules using the docking methodology.


Assuntos
Acetilcolinesterase/metabolismo , Benzeno/química , Benzeno/farmacologia , Butirilcolinesterase/metabolismo , Carbamatos/química , Carbamatos/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Animais , Benzeno/síntese química , Carbamatos/síntese química , Inibidores da Colinesterase/síntese química , Desenho de Drogas , Electrophorus , Cavalos , Concentração Inibidora 50 , Ligantes , Simulação de Acoplamento Molecular , Análise de Componente Principal , Probabilidade , Relação Estrutura-Atividade
12.
Exp Appl Acarol ; 77(4): 545-554, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30997606

RESUMO

The acaricide bifenazate acts as complex III inhibitor whereas cyenopyrafen and SYP-9625 act as complex II inhibitors. All these acaricides are commonly used to control two-spotted spider mite (TSSM), Tetranychus urticae Koch. We examined field-evolved and laboratory-selected resistance of TSSM to these three acaricides and determined cross-resistance among them. Six field populations of TSSM showed low levels of resistance to bifenazate with resistance ratios ranging from 2.20 to 10.65 compared to a susceptible strain. SYP-9625, structurally similar to cyenopyrafen, showed slightly higher activity to TSSMs but significant cross-resistance in both field populations and a laboratory-selected strain by SYP-9625. However, low levels of resistance to these two chemicals were found in field populations even when used for short time periods. Cross-resistance was not found between bifenazate and Complex II inhibitors, cyenopyrafen and SYP-9625, in both field populations and the laboratory-selected strain. Field-evolved resistance of TSSM to the tested acaricides is still low and should be delayed by the implementation of resistance management practices. Cross-resistance between cyenopyrafen and SYP-9625 is obvious, so they should not be used together in resistance management strategies based on mode of action rotation.


Assuntos
Acaricidas/farmacologia , Evolução Biológica , Resistência a Medicamentos , Tetranychidae/efeitos dos fármacos , Acrilonitrila/análogos & derivados , Acrilonitrila/farmacologia , Animais , Carbamatos/farmacologia , China , Hidrazinas/farmacologia , Pirazóis/farmacologia , Tetranychidae/fisiologia
13.
Ecotoxicology ; 28(5): 487-498, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30969407

RESUMO

The effect of pesticides on arbuscular mycorrhizal (AM) fungi and plants are of interest to agriculture. Hence, the present study was conducted to understand the potential effect of two systemic fungicides (Ridomil "250 and 500 mg/L" and Bavistin "500 and 1000 mg/L") and one insecticide (Agrothoate 40% EC "1.25 and 2.50 ml/L H2O") on AM fungal colonization, some biochemical changes and K+ content of cucumber plants (Cucumis sativus L.). AM and non-AM cucumber plants were exposed to two concentrations of each pesticide. Results revealed an increase in mycorrhizal colonization (F%) with Ridomil and Bavistin applications however there was a decrease in this percentage with Agrothoate. Stimulation of phosphatase enzymes activity was observed subsequent to pesticides application. Moreover, there was a significant decrease in K+ content with increasing pesticides concentration, and this decrease was more distinct in non-AM cucumber plants than AM ones. Our results also showed a significant increase in malondialdehyde (MDA) content in all pesticides treated cucumber plants relative to control ones. Thus, the content of non-enzymatic antioxidants such as phenolic and flavonoids was stimulated by pesticides application and with AM fungal inoculation, further augmentation in their contents was detected. Therefore AM fungi can partially or completely alleviate pesticides toxicity and helpful to overcome some of their negative effects on the biochemical metabolites of cucumber. Thus the judicious use of these pesticides may have stimulatory effect on AM fungal colonization.


Assuntos
Cucumis sativus/química , Fungicidas Industriais/farmacologia , Inseticidas/farmacologia , Micorrizas/efeitos dos fármacos , Potássio/análise , Alanina/análogos & derivados , Alanina/farmacologia , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Micorrizas/química , Micorrizas/fisiologia
14.
J Microbiol Biotechnol ; 29(5): 713-720, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31030451

RESUMO

Acanthamoeba castellanii belonging to the T4 genotype may cause a fatal brain infection known as granulomatous amoebic encephalitis, and the vision-threatening eye infection Acanthamoeba keratitis. The aim of this study was to evaluate the antiamoebic effects of three clinically available antidiabetic drugs, Glimepiride, Vildagliptin and Repaglinide, against A. castellanii belonging to the T4 genotype. Furthermore, we attempted to conjugate these drugs with silver nanoparticles (AgNPs) to enhance their antiamoebic effects. Amoebicidal, encystation, excystation, and host cell cytotoxicity assays were performed to unravel any antiacanthamoebic effects. Vildagliptin conjugated silver nanoparticles (Vgt-AgNPs) characterized by spectroscopic techniques and atomic force microscopy were synthesized. All three drugs showed antiamoebic effects against A. castellanii and significantly blocked the encystation. These drugs also showed significant cysticidal effects and reduced host cell cytotoxicity caused by A. castellanii. Moreover, Vildagliptin-coated silver nanoparticles were successfully synthesized and are shown to enhance its antiacanthamoebic potency at significantly reduced concentration. The repurposed application of the tested antidiabetic drugs and their nanoparticles against free-living amoeba such as Acanthamoeba castellanii described here is a novel outcome that holds tremendous potential for future applications against devastating infection.


Assuntos
Acanthamoeba castellanii/efeitos dos fármacos , Amebicidas/farmacologia , Anti-Infecciosos/farmacologia , Hipoglicemiantes/farmacologia , Nanoconjugados/química , Amebicidas/química , Anti-Infecciosos/química , Carbamatos/química , Carbamatos/farmacologia , Células HeLa , Humanos , Hipoglicemiantes/química , Nanopartículas Metálicas/química , Piperidinas/química , Piperidinas/farmacologia , Prata/química , Compostos de Sulfonilureia/química , Compostos de Sulfonilureia/farmacologia , Vildagliptina/química , Vildagliptina/farmacologia
15.
Mater Sci Eng C Mater Biol Appl ; 99: 315-321, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889705

RESUMO

Diatomite as a promising natural material is filled into poly(acrylamide) (PAAm) to synthesize PAAm/diatomite composite hydrogel. The internal chemistry structure of PAAm/diatomite composite hydrogel and the diatomite dispersion are characterized via Attenuated total reflection Fourier transform infrared (ATR-FTIR) and scanning electron microscopy (SEM). The mechanical property, water absorbency, and transparency of PAAm/diatomite composite hydrogels filled with different contents of diatomite are systematically investigated. The tensile and compressive strengths of PAAm/diatomite composite hydrogels are improved twice and 13-fold with 8 phr of diatomite. The water absorbency and transparency of PAAm/diatomite composite hydrogel decrease with the increase of diatomite content. The diatomite in PAAm hydrogels is not merely filling the bulk of PAAm hydrogel but is connecting with PAAm via hydrogen bonding. Carbendazim as a broad-spectrum benzimidazole fungicide is used to investigate the release property and kinetics of the composite hydrogels. The PAAm hydrogels can decrease the release rate of carbendazim and prolong the carbendazim efficacy, especially for the diatomite composite hydrogel. The time of half carbendazim release from the diatomite composite hydrogel is prolonged for almost 4 days, and the release mechanism is anomalous transport. Thus, diatomite can improve the mechanical property of PAAm hydrogel and extend the carbendazim efficacy loaded with PAAm hydrogel. Considering more widely applicable, the diatomite composite hydrogel can be applied to reduce the loss and waste of drugs and prolong the duration of drugs in biomedical materials.


Assuntos
Resinas Acrílicas/química , Terra de Diatomáceas/química , Hidrogéis/química , Fenômenos Mecânicos , Benzimidazóis/química , Benzimidazóis/farmacologia , Carbamatos/química , Carbamatos/farmacologia , Liberação Controlada de Fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
16.
Plant Dis ; 103(5): 929-937, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30880557

RESUMO

Fusarium graminearum species complex (FGSC), causing Fusarium head blight (FHB) of wheat, has species-specific geographical distributions in wheat-growing regions. In recent years, benzimidazole resistance of FHB pathogens has been largely widespread in China. Although the demethylation inhibitor fungicide metconazole has been used for FHB control in some countries, no information about metconazole sensitivity of Chinese FHB pathogen populations and efficacy of metconazole in FHB control in China is available. In this study, the sensitivity of FGSC to metconazole was measured with 32 carbendazim-sensitive strains and 35 carbendazim-resistant strains based on mycelial growth. The 50% effective concentration values of 67 strains were normally distributed and ranged from 0.0209 to 0.0838 µg ml-1, with a mean of 0.0481 ± 0.0134 µg ml-1. No significant difference in metconazole sensitivity was observed between carbendazim-sensitive and -resistant populations. An interactive effect of metconazole and phenamacril, a novel cyanoacrilate fungicide approved in China against Fusarium spp., in inhibiting mycelial growth showed an additive interaction at different ratios. Furthermore, field trials to evaluate the effect of metconazole and metconazole + phenamacril treatments in FHB control, deoxynivalenol (DON) production, and grain yields were performed. Compared with the fungicides carbendazim and phenamacril currently used in China, metconazole exhibits a better efficacy for FHB control, DON production, and grain yields, and dramatically reduces use dosages of chemical compounds in the field. The mixture of metconazole and phenamacril at ratios of 2:3 and 1:2 showed the greatest efficacy for FHB control, DON production, and grain yields among all the fungicide treatments but its use dosages were higher in comparison with metconazole alone. In addition, FHB control, grain yields, and DON levels were significantly correlated with each other, showing that visual disease indices can be used as an indicator of grain yields and DON contamination. Meanwhile, the frequency of carbendazim-resistant alleles in F. graminearum populations was dramatically reduced after metconazole and phenamacril alone and the mixture of metconazole and phenamacril applications, indicating that metconazole and a mixture of metconazole and phenamacril can be used for carbendazim resistance management of FHB in wheat. Overall, the findings of this study provide important data for resistance management of FHB and reducing DON contamination in wheat grains.


Assuntos
Farmacorresistência Fúngica , Fungicidas Industriais , Fusarium , Benzimidazóis/farmacologia , Carbamatos/farmacologia , China , Farmacorresistência Fúngica/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Triazóis/farmacologia , Triticum/microbiologia
17.
Chemosphere ; 226: 36-46, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30913426

RESUMO

In this study, fenamidone, propamocarb and their transformation products were monitored in cherry tomato, cucumber, and courgette samples. A mixture of both compounds, which have different physico-chemical characteristics, are commercially available (Consento®). For analysis, ultra high-performance liquid chromatography coupled to Orbitrap mass spectrometry (UHPLC-Orbitrap-MS) and gas chromatography coupled to Q-Orbitrap mass spectrometry (GC-Q-Orbitrap-MS) were used. The dissipation of these active ingredients was monitored at two doses (normal and double dose) from 1 to 40 days after the application of the commercial product. Half-lives (DT50) were lower than 30 days for both compounds, which indicates low persistence. Metabolites of both compounds were also monitored due to in some cases these can be more dangerous for human health than the parent compounds. The metabolites monitored were RPA 410193 ((5S)-3-anilino-5-methyl-5-phenylimidazolidine-2,4-dione), acetophenone, 2-phenylpropionic acid, 5-methyl-5-phenylhydantoin and 5-methylhydantoin for fenamidone, and propamocarb hydrochloride (propyl 3-(dimethylamino)propylcarbamate hydrochloride), N-oxide propamocarb (propyl [3-(dimethylnitroryl)propyl]carbamate), oxazoline-2-one propamocarb (3-[3-(dimethylamino)propyl]-4-hydroxy-4-methyl-1,3-oxazolidin-2-one), 2-hydroxypropamocarb and n-desmethyl propamocarb (propyl [3-(methylamino)propyl]carbamate) for propamocarb. In addition, they were detected one day after the application of commercial product, being RPA 410193, the metabolite detected at the highest concentration in samples. Retrospective analysis of incurred samples allowed putative identification of four possible new metabolites of propamocarb and one of fenamidone.


Assuntos
Carbamatos/uso terapêutico , Cromatografia Líquida de Alta Pressão/métodos , Fungicidas Industriais/uso terapêutico , Cromatografia Gasosa-Espectrometria de Massas/métodos , Estrobilurinas/uso terapêutico , Verduras/química , Carbamatos/farmacologia , Fungicidas Industriais/farmacologia , Humanos , Cinética , Estudos Retrospectivos , Estrobilurinas/farmacologia
18.
BMC Genomics ; 20(1): 115, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30732567

RESUMO

BACKGROUND: Pokkah boeng is one of the most serious and devastating diseases of sugarcane and causes significant loss in cane yield and sugar content. Although carbendazim is widely used to prevent fungal diseases, the molecular basis of Fusarium species complex (FSC) resistance to carbendazim remains unknown. RESULTS: The EC50 (fungicide concentration that inhibits 50% of mycelial growth) values of carbendazim for 35 FSC isolates collected in cane growing regions of China were ranged from 0.5097 to 0.6941 µg mL- 1 of active ingredient (a.i.), in an average of 0.5957 µg a.i. mL- 1. Among carbendazim-induced mutant strains, SJ51M (F. verticillioides) had a CTG rather than CAG codon (Q134L) at position 134 of the FVER_09254 gene, whereas in the mutant strain HC30M (F. proliferatum) codon ACA at position 351 of the FPRO_07779 gene was replaced by ATA (T351I). Gene expression profiling analysis was performed for SJ51M and its corresponding wild type strain SJ51, with and without carbendazim treatment. The gene expression patterns in SJ51 and SJ51M changed greatly as evidenced by the detection of 850 differentially expressed genes (DEGs). Functional categorization indicated that genes associated with oxidation-reduction process, ATP binding, integral component of membrane, transmembrane transport and response to stress showed the largest expression changes between SJ51M and SJ51. The expression levels of many genes involved in fungicide resistance, such as detoxification enzymes, drug efflux transporters and response to stress, were up-regulated in SJ51M compared to SJ51 with and without carbendazim treatment. CONCLUSION: FSC was sensitive to carbendazim and had the potential for rapid development of carbendazim resistance. The transcriptome data provided insight into the molecular pathways involved in FSC carbendazim resistance.


Assuntos
Benzimidazóis/farmacologia , Carbamatos/farmacologia , Farmacorresistência Fúngica/genética , Fusarium/efeitos dos fármacos , Fusarium/fisiologia , Doenças das Plantas/microbiologia , Saccharum/microbiologia , Fusarium/genética , Genes Fúngicos/genética , Mutação , Temperatura Ambiente , Transcriptoma/efeitos dos fármacos
19.
Acta Trop ; 193: 148-157, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30742803

RESUMO

Anopheles sacharovi and Anopheles superpictus have a significant public health importance since they are primer and seconder malaria vectors of Turkey, respectively. As a result of intensive insecticide usage in historically malaria endemic regions of Turkey for long years, insecticide resistance problem has occurred inevitably. In this study, we aimed to investigate the involvement of the detoxification enzymes in insecticide resistance in Turkish An. sacharovi and An. superpictus populations in the Mediterranean and South-eastern Anatolia region where have a malaria history in the past. Bioassay results indicated that both An. sacharovi and An. superpictus populations are resistant to DDT, resistant or possible resistant to organophosphates and carbamates and finally mostly susceptible to pyrethroids. Although bioassays results indicated high DDT resistance in all mosquito populations, biochemical assays did not show significantly high GST levels in all strains. Almost all An. sacharovi and An. superpictus populations had an increased α and ß esterase activity levels while nearly half of the overall populations had an increased p-NPA esterase than the control group. Elevated levels of MFO frequency have been shown in the majority of the populations. Consequently, our results reveal that biochemical resistance mechanisms may play an important role in insecticide resistance in Turkish An. sacharovi and An. superpictus populations. These results give useful cues to monitor the insecticide resistance before it spreads throughout an entire population, enabling early intervention.


Assuntos
Anopheles/efeitos dos fármacos , Esterases/metabolismo , Resistência a Inseticidas , Inseticidas/farmacologia , Malária/epidemiologia , Mosquitos Vetores/efeitos dos fármacos , Animais , Anopheles/enzimologia , Carbamatos/farmacologia , DDT/farmacologia , Doenças Endêmicas , Feminino , Glutationa Transferase/metabolismo , Humanos , Oxigenases de Função Mista/metabolismo , Mosquitos Vetores/enzimologia , Organofosfatos/farmacologia , Piretrinas/farmacologia , Turquia/epidemiologia
20.
Int J Mol Sci ; 20(3)2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30704062

RESUMO

The 18 kDa Translocator Protein (TSPO) is a marker for microglial activation as its expression is enhanced in activated microglia during neuroinflammation. TSPO ligands can attenuate neuroinflammation and neurotoxicity. In the present study, we examined the efficacy of new TSPO ligands designed by our laboratory, MGV-1 and 2-Cl-MGV-1, in mitigating an in vitro neuroinflammatory process compared to the classic TSPO ligand, PK 11195. We exposed BV-2 microglial cells to lipopolysaccharide (LPS) for 24 h to induce inflammatory response and added the three TSPO ligands: (1) one hour before LPS treatment (pretreatment), (2) simultaneously with LPS (cotreatment), and (3) one hour after LPS exposure (post-treatment). We evaluated the capability of TSPO ligands to reduce the levels of three glial inflammatory markers: cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and nitric oxide (NO). We compared the effects of the two novel ligands to PK 11195. Both 2-Cl-MGV-1 and MGV-1 reduced the levels of glial COX-2, iNOS, and NO in LPS-treated BV-2 cells more efficiently than PK 11195. Notably, even when added after exposure to LPS, all ligands were able to suppress the inflammatory response. Due to their pronounced anti-inflammatory activity, 2-Cl-MGV-1 and MGV-1 may serve as potential therapeutics in neuroinflammatory and neurodegenerative diseases.


Assuntos
Carbamatos/farmacologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Isoquinolinas/farmacologia , Lipopolissacarídeos/toxicidade , Microglia/efeitos dos fármacos , Microglia/metabolismo , Quinazolinas/farmacologia , Receptores de GABA/metabolismo , Animais , Western Blotting , Linhagem Celular , Camundongos
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