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1.
Pol Merkur Lekarski ; 52(4): 427-432, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39360723

RESUMO

OBJECTIVE: Aim: The aim of the study was to investigate the activity of bioenergetic processes in rats under conditions of simultaneous exposure to malathion and carbon tetrachloride and after the use of enterosgel. PATIENTS AND METHODS: Materials and Methods: Experiments were conducted on rats. The rats were divided into nine groups.Malathion was administered daily (for 30 days) at a dose of 20 mg / kg body weight of the animal. Tetrachloromethane was administered twice (every other day) as a 50% oil solution at a dose of 1.0 ml / kg body weight. The intensity of energy supply processes was assessed by the activity of succinate dehydrogenase and cytochrome oxidase, impaired carbohydrate metabolism in terms of glucose and glycogen. RESULTS: Results: It was noted that succinate dehydrogenase activity in the liver decreased 2 times, in the myocardium - 1.6 times. On the thirty and seventh day of administration of toxicants after enterosorbent use, succinate dehydrogenase activity increased in the liver by 20%, cytochrome oxidase by 27%, in the myocardium - by 31% and 23%, respectively. The content of glucose in the serum after exposure to toxicants increased maximally (2.4 times) at the end of the study. In contrast, the glycogen content in the liver decreased by 48%, in the myocardium by 13%. The use of enterosgel resulted in a decrease in serum glucose. CONCLUSION: Conclusions: The use of enterosgel leads to the restoration of energy processes in the body of affected rats, which is confirmed by increased activity of mitochondrial enzymes, lowering glucose and increasing glycogen in the studied organs.


Assuntos
Tetracloreto de Carbono , Metabolismo Energético , Fígado , Malation , Succinato Desidrogenase , Animais , Ratos , Metabolismo Energético/efeitos dos fármacos , Succinato Desidrogenase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/enzimologia , Masculino , Miocárdio/metabolismo , Ratos Wistar , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glucose/metabolismo , Glicogênio/metabolismo , Inseticidas
2.
Animals (Basel) ; 14(19)2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39409863

RESUMO

The widespread use of malathion may offer several hazards to humans and animals; additionally, many medicinal plants provide what is known as a broad antitoxicity treatment. This study was carried out to investigate hazardous biochemical and histological reactions to MOP and evaluate the effectiveness of TEO and OEO essential oils in restoring normal physiological conditions after MOP exposure by measuring enzyme-specific activity for Cytochrome P450 1A2 (CYP1A2). One hundred and twenty rats were divided into six groups of twenty animals each: (i) C - MOP served as the control group, (ii) C + MOP treated with 5 mg/kg/BW of Malathion-D10, (iii) TEO treated with 100 mg/kg/BW of oregano essential oil, (iv) TEO treated with 100 mg/kg/BW of thyme essential oil, (v) MOP + OEO treated with 5 mg/kg/BW of Malathion-D10 and 100 mg/kg/BW of oregano essential oil, and (vi) MOP + TEO treated with 5 mg/kg/BW of Malathion-D10 and 100 mg/kg/BW of thyme essential oil. The results indicated the protective effects of OEO and TEO against MOP-induced weight loss. Additionally, there was a significant improvement in ALT, AST, and ALK-Ph after being treated with OEO and TEO, either alone or after MOP exposure. Also, treatment with OEO and TEO ameliorated these oxidative stress parameters, indicating their antioxidative properties. A histopathological examination of liver tissues showed reduced hepatocellular damage and improved liver architecture in the OEO and TEO, both alone and in combination with MOP, and protective effects were more pronounced in the TEO-treated groups. However, the results indicated that TEO was more effective than OEO in increasing CYP1A2 expression and alleviating MOP-induced toxicity. Specifically, TEO showed higher protein expression and therapeutic action in reducing liver damage. In conclusion, these findings suggest that OEO and TEO may be potent therapeutic agents against MOP toxicity, offering protective effects by enhancing CYP1A2 activity and mitigating organ damage. Such knowledge would be an important step toward developing potentially unique treatment options for natural antitoxins.

3.
Food Chem X ; 24: 101835, 2024 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-39347499

RESUMO

An aptasensor with dual-outputs was developed for malathion detection. Fe-MOF was synthesized to design favorable signal probes for catalytic amplification. Owing to the excellent peroxidase-like activity of Fe-MOF, the redox reaction was catalyzed to produce the dual-outputs of colorimetric and electrochemical. In this sensing strategy, malathion was captured by the aptamer on sensing interface, leading to the release of signal probe. Thanks to the catalytic amplification of Fe-MOF and the high capture effect of aptamer, the aptasensor produced a sensitive response for malathion. Based on the dual-signals of absorbance and current, the detection method for malathion was developed ranging from 10 ng/mL to 500 ng/mL. The detection limit of malathion was 5.8 ng/mL for colorimetric output and 4.6 ng/mL for electrochemical output. Furthermore, the aptasensor exhibited high specificity and good repeatability in malathion detection. Finally, the aptasensor was applied to detect malathion in fruit and vegetable samples with satisfactory recovery.

4.
Animals (Basel) ; 14(17)2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39272282

RESUMO

The widespread use of MLT may pose numerous hazards to animal breeding, health, and resilience due to the presence of MLT residues in animal feedstuffs, pastures, hay, and cereals. Many medicinal plants provide what is called a generalized anti-toxic remedy. The current study examined hazardous biochemical and histological reactions to MLT and the efficiency of ThEO and OEO essential oils as anti-toxic therapies to return to a natural state after MLT exposure. A total of 75 male albino rats were randomly assigned to two groups: (i) C - MLT, comprising 25 rats, served as the control group; and (ii) C + MLT, with 50 rats that were exposed to 5 mg/kg/BW. After exposure to MLT for 21 days, a return to normal status was determined by subdividing the C + MLT group into two equal groups: ThEO and OEO were used as treatments, with 100 mg/kg body weight of thyme and oregano essential oils, respectively, being administered for 21 days. The results showed a significant decrease in body weight gain (BWG) and final weight (FW) compared to C - MLT, while the therapeutic effects of ThEO and OEO enhanced FW and BWG. Our results indicated that MLT exposure resulted in deficient serum liver function, but that OEO and ThEO therapy brought about a significant improvement in liver enzyme function. Although there was no significant difference in serum aspartate transaminase (AST) or alkaline phosphatase (ALK-Ph) and a significant drop in alanine transaminase (ALT) and acetyl choline-esterase (AChE) levels, the C + MLT group showed hepatic fibrosis in the third stage. Furthermore, histological sections of the OEO and ThEO groups showed reduced hepatocellular damage, inflammation, and hepatic fibrosis. However, there was a significant increase in serum creatinine between the C + MLT and C - MLT groups following exposure to MLT. Histological sections of renal tissue from rats treated with OEO and ThEO showed reduced tubular damage, reduced interstitial inflammation, and preserved renal tissue architecture. In conclusion, OEO and ThEO are potential compounds for use as anti-toxic therapies to return to a natural state after MLT exposure. These compounds could serve as an experimental therapeutic approach against natural toxins, providing a solution to the problems of raising livestock that are exposed to nutritional toxicity.

5.
J Med Entomol ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39257062

RESUMO

Forensic entomology plays a crucial role in estimating the minimum postmortem interval through the study of insect larvae found at crime scenes. The precision of this estimation relies on various biotic and abiotic elements that simultaneously influence insect growth and development, encompassing factors such as temperature, humidity, photoperiod, diet, and the existence of xenobiotics in decomposing tissues. Despite numerous studies on the influence of these factors, including the impact of xenobiotics, there are currently no robust tools available for making corrections to this estimation considering concurrently all variables. In an attempt to propose an exploratory and descriptive statistical model to analyze the simultaneous effect and interaction of different variables on larval growth, this study aimed to compare the effect of malathion on the growth of Megaselia scalaris (Loew, 1866) (Diptera: Phoridae) raised in malathion-spiked porcine muscle, under controlled and uncontrolled temperature and humidity conditions (environmental conditions). Larvae were also reared using various growth media. A split-plot design that combined crossed and nested factors was employed; 2 linear mixed models were developed to assess the relationships between the variables. The model provides valuable insights into the complex interactions among xenobiotics, growth media, and environmental conditions in the size and development of M. scalaris.

6.
J Xenobiot ; 14(3): 1238-1255, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39311149

RESUMO

This study investigates using KOH-activated coffee grounds (KACGs) as an effective adsorbent for removing organophosphorus xenobiotics malathion and chlorpyrifos from water. Malathion and chlorpyrifos, widely used as pesticides, pose significant health risks due to their neurotoxic effects and environmental persistence. Spent coffee grounds, abundant biowaste from coffee production, are chemically activated with KOH to enhance their adsorptive capacity without thermal treatment. This offers a sustainable solution for biowaste management and water remediation. Adsorption kinetics indicating rapid initial adsorption with high affinity were observed, particularly for chlorpyrifos. Isotherm studies confirmed favorable adsorption conditions, with higher maximum adsorption capacities for chlorpyrifos compared to malathion (15.0 ± 0.1 mg g-1 for malathion and 22.3 ± 0.1 mg g-1 for chlorpyrifos), highlighting its potential in mitigating water pollution. Thermodynamic analysis suggested the adsorption process was spontaneous but with the opposite behavior for the investigated pesticides. Malathion interacts with KACGs via dipole-dipole and dispersion forces, while chlorpyrifos through π-π stacking with aromatic groups. The reduction in neurotoxic risks associated with pesticide exposure is also shown, indicating that no more toxic products were formed during the remediation. This research contributes to sustainable development goals by repurposing biowaste and addressing water pollution challenges through innovative adsorbent materials.

7.
Biosens Bioelectron ; 267: 116808, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39326319

RESUMO

Malathion (MALA), a widely used insecticide, even at trace levels exhibits deleterious effects towards respiratory tracts, and nervous system, necessitating its detection. Herein, we have offered non-enzymatic trace level monitoring of MALA using g-C3N4 supported CuO-derived biochar. The present B-CuO/g-C3N4 based electrochemical sensor is synthesized using hydrothermal approach followed by calcination at high temperature. The result unveiled the strong interactions, high charge separation efficiency, significant porosity leading to excellent electrochemically active surface area 9.88 × 10-5 cm2 with least charge transfer resistance (RCT) value of 35.2 K Ω. The B-CuO/g-C3N4 based nanocomposite offered excellent complex formation ability with MALA and square wave anodic stripping voltametric method (SWASV) generates an enhanced electrochemical signal due to oxidation of MALA. Following all necessary optimizations, the sensor was capable to exhibit limit of detection (LOD) value of 1.2 pg mL-1 with R2 = 0.968. The modified biosensor offered its potential towards detection of MALA in apple and tomato samples with a recovery ranging from 87.64 to 120.59%. This novel B-CuO/g-C3N4 ternary nanocomposite provides non-enzymatic detection of MALA having excellent electrochemical properties and hence opens new pathways for exploring the use of biochar in other electrochemical applications.

8.
J Hazard Mater ; 477: 135358, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39088958

RESUMO

To address the potential hazards of organophosphorus pesticides (OPs) residues in tea, an electrochemiluminescence (ECL) aptasensor based on functionalized nanomaterials was constructed in this work. Firstly, gold nanoparticles (AuNPs) were attached on the surface of multi-walled carbon nanotubes (MWCNTs) by the constant potential electrodeposition to form a compound, and it was utilized to provide excellent immobilization sites for complementary DNA (cDNA). Subsequently, composite nanomaterials were synthesized by a one-pot method with aminated Luminol/silver nanoparticles@silica nanospheres (NH2-Luminol/Ag@SiO2NSs). Finally, NH2-Luminol/Ag@SiO2NSs was combined with a malathion aptamer (Apt) to obtain signal probes (SPs) for the construction of an aptasensor. The aptasensor had a wide linear range (1×10-3-1×103 ng/mL) and a low limit of detection (LOD) (0.3×10-3 ng/mL). It had the virtues of high sensitivity, wonderful stability and excellent specificity, which could be used for the detection of malathion residue in tea. The work provides a proven way for the construction of a rapid and ultrasensitive aptasensor with low-cost.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Medições Luminescentes , Luminol , Malation , Nanopartículas Metálicas , Dióxido de Silício , Prata , Chá , Malation/análise , Malation/química , Chá/química , Nanopartículas Metálicas/química , Luminol/química , Prata/química , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Dióxido de Silício/química , Ouro/química , Aptâmeros de Nucleotídeos/química , Resíduos de Praguicidas/análise , Nanotubos de Carbono/química , Contaminação de Alimentos/análise , Técnicas Biossensoriais/métodos
9.
Food Chem ; 460(Pt 1): 140563, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39053269

RESUMO

Herein, a novel electrochemical sensor based on zirconium-doped cobalt oxyhydroxide (ZrCoOOH) was proposed for highly sensitive non-enzymatic determination of malathion (MAL). The doping of Zr can improve the electrical conductivity of CoOOH, of which the transfer resistance was reduced from 241.1 Ω to 140.2 Ω. Furthermore, the X-ray photoelectron spectroscopy confirmed that part of Co2+ was converted to Co3+ due to the introduction of Zr. The Co3+ in ZrCoOOH could react with MAL to form Co2+, which enhanced the electrooxidation current of Co2+. Therefore, the peak current of Co2+ was served as detection probe for MAL. Under optimal conditions, the developed sensor established the linear relationship for MAL in the concentration range of 0.001-10.0 µM with a low limit of detection (0.64 nM). The constructed sensor was employed to detect MAL in food samples (peach, kiwi fruit, spinach and tomato), verifying the accuracy and practicability of the sensor.


Assuntos
Cobalto , Condutividade Elétrica , Técnicas Eletroquímicas , Contaminação de Alimentos , Malation , Zircônio , Cobalto/química , Zircônio/química , Contaminação de Alimentos/análise , Malation/análise , Malation/química , Técnicas Eletroquímicas/instrumentação , Limite de Detecção , Óxidos/química , Frutas/química
10.
J Hazard Mater ; 476: 135162, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39002482

RESUMO

Iron oxide @ biochar (FeO/C) promotes bacterial growth and facilitates electron transfer, thereby effectively promoting malathion degradation by Shewanella oneidensis MR-1 (S. oneidensis MR-1). This study elucidated the underlying mechanism of FeO/C-enhanced malathion degradation by S. oneidensis MR-1 through a combination of metabolomics and proteomics analysis. The kinetic fitting results from the degradation experiment indicated that 0.1 g/L FeO/C exerted the most significant enhancement effect on malathion degradation by S. oneidensis MR-1. Observations from Scanning Electron Microscopy and Laser Scanning Confocal Microscopy, along with physiological and biochemical analysis, showed that FeO/C enhanced the growth and oxidative response of S. oneidensis MR-1 under malathion stress. In addition, metabolomics and proteomics analysis revealed an increase in certain electron transfer related metabolites, such as coenzymes, and the upregulation of proteins, including coenzyme A, sdhD, and petC. Overall, spectroscopic analysis suggested that Fe2+, which was reduced from Fe3+ by S. oneidensis MR-1 in FeO/C, promoted electron transfer in S. oneidensis MR-1 to enhance the degradation of malathion. This study offers enhanced strategies for efficient removal of malathion contaminants.


Assuntos
Compostos Férricos , Malation , Metabolômica , Proteômica , Shewanella , Malation/metabolismo , Shewanella/metabolismo , Shewanella/efeitos dos fármacos , Compostos Férricos/metabolismo , Compostos Férricos/química , Biodegradação Ambiental , Inseticidas/metabolismo , Inseticidas/química , Proteínas de Bactérias/metabolismo
12.
Chemosphere ; 362: 142700, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38936485

RESUMO

Pesticides are significant environmental pollutants, and many of them possess mutagenic potential, which is closely linked to carcinogenesis. Here we tested the mutagenicity of all six pesticides classified probably carcinogenic (Group 2A) by the International Agency of Research on Cancer: 4,4'-DDT, captafol, dieldrin, diazinon, glyphosate and malathion. Whole genome sequencing of TK6 human lymphoblastoid cell clones following 30-day exposure at subtoxic concentrations revealed a clear mutagenic effect of treatment with captafol or malathion when added at 200 nM or 100 µM initial concentrations, respectively. Each pesticide induced a specific base substitution mutational signature: captafol increased C to A mutations primarily, while malathion induced mostly C to T mutations. 4,4'-DDT, dieldrin, diazinon and glyphosate were not mutagenic. Whereas captafol induced chromosomal instability, H2A.X phosphorylation and cell cycle arrest in G2/M phase, all indicating DNA damage, malathion did not induce DNA damage markers or cell cycle alterations despite its mutagenic effect. Hypersensitivity of REV1 and XPA mutant DT40 chicken cell lines suggests that captafol induces DNA adducts that are bypassed by translesion DNA synthesis and are targets for nucleotide excision repair. The experimentally identified mutational signatures of captafol and malathion could shed light on the mechanism of action of these compounds. The signatures are potentially suitable for detecting past exposure in tumour samples, but the reanalysis of large cancer genome databases did not reveal any evidence of captafol or malathion exposure.


Assuntos
Testes de Mutagenicidade , Mutagênicos , Praguicidas , Humanos , Praguicidas/toxicidade , Mutagênicos/toxicidade , Dano ao DNA , Carcinógenos/toxicidade , Animais , Mutação , Linhagem Celular , Poluentes Ambientais/toxicidade
13.
Pestic Biochem Physiol ; 202: 105906, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879292

RESUMO

Early detection of insecticide resistance is essential to develop resistance countermeasures and depends on accurate and rapid biological and biochemical tests to monitor resistance and detect associated mechanisms. Many such studies have measured activities of esterases, enzymes associated with resistance to ester- containing insecticides, using the model substrate, α-naphthyl acetate (α-NA). However, in the field, pests are exposed to ester-containing insecticides such as malathion, that are structurally distinct from α-NA. In the current study, malathion resistance in C. quinquefasciatus (3.2- to 10.4-fold) was highly associated with esterase activity measured with either α-NA (R2 = 0.92) or malathion (R2 = 0.90). In addition, genes encoding two esterases (i.e., EST-2 and EST-3) were over-expressed in field- collected strains, but only one (EST-3) was correlated with malathion hydrolysis (R2 = 0.94) and resistance (Rs = 0.96). These results suggest that, in the strains studied, α-NA is a valid surrogate for measuring malathion hydrolysis, and that heightened expression of an esterase gene is not necessarily associated with metabolic resistance to insecticidal esters.


Assuntos
Culex , Esterases , Resistência a Inseticidas , Inseticidas , Malation , Malation/farmacologia , Animais , Esterases/metabolismo , Esterases/genética , Culex/efeitos dos fármacos , Culex/genética , Culex/enzimologia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Naftalenos/farmacologia , Hidrólise , Biomarcadores/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Naftóis
14.
Mikrochim Acta ; 191(7): 368, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833176

RESUMO

A colorimetric analysis platform has been successfully developed based on FeCo-NC dual-atom nanozyme (FeCo-NC DAzyme) for the detection of organophosphorus pesticides (OPPs). The FeCo-NC DAzyme exhibited exceptional oxidase-like activity (OXD), enabling the catalysis of colorless TMB to form blue oxidized TMB (oxTMB) without the need for H2O2 involvement. By combining acid phosphatase (ACP) hydrolase with FeCo-NC DAzyme, a "FeCo-NC DAzyme + TMB + ACP + SAP" colorimetric system was constructed, which facilitated the rapid detection of malathion. The chromogenic system was applied to detect malathion using a smartphone-based app and an auxiliary imaging interferogram device for colorimetric measurements, which have a linear range of 0.05-4.0 µM and a limit of detection (LOD) as low as 15 nM in real samples, comparable to UV-Vis and HPLC-DAD detection methods. Overall, these findings present a novel approach for convenient, rapid, and on-site monitoring of OPPs.


Assuntos
Colorimetria , Limite de Detecção , Praguicidas , Smartphone , Colorimetria/métodos , Praguicidas/análise , Compostos Organofosforados/análise , Compostos Organofosforados/química , Malation/análise , Malation/química , Oxirredutases/química , Ferro/química , Fosfatase Ácida/análise , Fosfatase Ácida/química , Benzidinas
15.
Sci Total Environ ; 935: 173262, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38768719

RESUMO

Growing concerns about pesticide residues in agriculture are pushing the scientific community to develop innovative and efficient methods for detecting these substances at low concentrations down to the molecular level. In this context, surface-enhanced Raman spectroscopy (SERS) is a powerful analytical method that has so far already undergone some validation for its effectiveness in pesticide detection. However, despite its great potential, SERS faces significant difficulties obtaining reproducible and accurate pesticide spectra, particularly for some of the most widely used pesticides, such as malathion, chlorpyrifos, and imidacloprid. Those inconsistencies can be attributed to several factors, such as interactions between pesticides and SERS substrates and the variety of substrates and solvents used. In addition, differences in the equipment used to obtain SERS spectra and the lack of standards for control experiments further complicate the reproducibility and reliability of SERS data. This review systematically discusses the problems mentioned above, including a comprehensive analysis of the challenges in precisely evaluating SERS spectra for pesticide detection. We not only point out the existing limitations of the method, which can be traced in previous review works, but also offer practical recommendations to improve the quality and comparability of SERS spectra, thereby expanding the potential applications of the method in such an essential field as pesticide detection.

16.
Eur J Obstet Gynecol Reprod Biol ; 298: 49-52, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38728841

RESUMO

BACKGROUND AND PURPOSE: Organophosphate pesticides such as malathion are the most widely used pesticides. Despite endocrine-disrupting effects, there is a paucity of information regarding chronic exposure to non-persistent organopesticides such as malathion. The purpose of this study is to describe the exposure burden among U.S. residents as well as possible impacts on fertility. METHODS: Population-based data collected by the National Health and Nutrition Examination Survey (NHANES) between 2015 and 2016 were used to perform a retrospective analysis on urinary concentrations of malathion diacid. Samples were assessed from 1703 adult participants, statistically weighted to represent over 231 million individuals. General linear models were used to examine associations between exposure and reproductive health measures among pre-menopausal women. RESULTS: Detectable concentrations of malathion diacid were identified in 16.1 % (n = 254) of samples. Concentrations were higher among women who reported seeing a physician due to difficulties becoming pregnant (P < 0.001; r2 = 0.12) as well as among women who reported trying for at least a year to become pregnant (P < 0.001; r2 = 0.06). CONCLUSIONS: Exposure to malathion is associated with a history of reproductive health challenges among women.


Assuntos
Malation , Inquéritos Nutricionais , Humanos , Malation/efeitos adversos , Malation/urina , Feminino , Adulto , Estados Unidos/epidemiologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Exposição Ambiental/efeitos adversos , Exposição Ambiental/estatística & dados numéricos , Adulto Jovem , Infertilidade/induzido quimicamente , Infertilidade/epidemiologia , Inseticidas/efeitos adversos , Inseticidas/urina , Gravidez
17.
Insects ; 15(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38786914

RESUMO

(1) Background: In Cambodia, Aedes albopictus is an important vector of the dengue virus. Vector control using insecticides is a major strategy implemented in managing mosquito-borne diseases. Resistance, however, threatens to undermine the use of insecticides. In this study, we present the levels of insecticide resistance of Ae. albopictus in Cambodia and the mechanisms involved. (2) Methods: Two Ae. albopictus populations were collected from the capital, Phnom Penh city, and from rural Pailin province. Adults were tested with diagnostic doses of malathion (0.8%), deltamethrin (0.03%), permethrin (0.25%), and DDT (4%) using WHO tube assays. Synergist assays using piperonyl butoxide (PBO) were implemented before the pyrethroid assays to detect the potential involvement of metabolic resistance mechanisms. Adult female mosquitoes collected from Phnom Penh and Pailin were tested for voltage-gated sodium channel (VGSC) kdr (knockdown resistance) mutations commonly found in Aedes sp.-resistant populations throughout Asia (S989P, V1016G, and F1534C), as well as for other mutations (V410L, L982W, A1007G, I1011M, T1520I, and D1763Y). (3) Results: The two populations showed resistance against all the insecticides tested (<90% mortality). The use of PBO (an inhibitor of P450s) strongly restored the efficacy of deltamethrin and permethrin against the two resistant populations. Sequences of regions of the vgsc gene showed a lack of kdr mutations known to be associated with pyrethroid resistance. However, four novel non-synonymous mutations (L412P/S, C983S, Q1554STOP, and R1718L) and twenty-nine synonymous mutations were detected. It remains to be determined whether these mutations contribute to pyrethroid resistance. (4) Conclusions: Pyrethroid resistance is occurring in two Ae. albopictus populations originating from urban and rural areas of Cambodia. The resistance is likely due to metabolic resistance specifically involving P450s monooxygenases. The levels of resistance against different insecticide classes are a cause for concern in Cambodia. Alternative tools and insecticides for controlling dengue vectors should be used to minimize disease prevalence in the country.

18.
Reprod Toxicol ; 126: 108595, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38641014

RESUMO

Malathion is an organophosphate pesticide used in agriculture and control of the Aedes aegypti mosquito. As previous reports have indicated the potential of malathion to compromise testosterone production in in vivo models, the objective of this study was to elucidate the mechanisms underlying the impairment of Leydig cell function, considering its critical role in male reproductive function. To this end, murine Leydig TM3 cells were exposed to concentrations of 1, 10, 100 or 1000 µM malathion for 24 h for evaluation of the compound on cell viability. Subsequently, concentrations of 1, 10, and 100 µM malathion were employed for a 24-h period to assess testosterone biosynthesis, levels of cytokines IL-1ß, IL-6, IL-10, and TNF-α, as well as the redox profile. Malathion exerted a concentration-dependent impact on cell viability. Notably, the lower concentrations of malathion (1 and 10 µM) were found to impair testosterone biosynthesis in TM3 cells. While there were changes in IL-1 and TNF-α levels at specific concentrations, no direct correlation with altered hormone production was established. Our investigation revealed that varied malathion concentrations induced oxidative stress by increase in superoxide anion and a compensatory rise in antioxidants. In conclusion, the observed changes in the oxidative profile of TM3 cells were linked to functional impairment, evidenced by reduced testosterone biosynthesis at lower malathion concentrations.


Assuntos
Sobrevivência Celular , Inseticidas , Células Intersticiais do Testículo , Malation , Oxirredução , Estresse Oxidativo , Testosterona , Malation/toxicidade , Animais , Testosterona/biossíntese , Masculino , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Camundongos , Inseticidas/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo
19.
Heliyon ; 10(7): e28438, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560236

RESUMO

Over the past decade, food safety has become a major concern due to the intensive use of pesticides. Pesticide contamination has been observed in poultry products when seeds are coated with pesticides or when stored products are exposed to pesticides in warehouses. In this experiment, the residue levels of malathion transferred from corn grain to the different parts of the chicken product, its transfer factors (TFs) and the human dietary risk for consumers were evaluated. Growth performance and carcass parameters of the chicken samples were also determined after different doses of malathion exposure. Malathion residues from different parts of chicken meat (breast, thigh, wing, liver and skin) were extracted by the QuEChERS method and analyzed by liquid chromatography-mass spectrophotometry (LC-MS/MS). A deterministic approach was used to calculate the acute and chronic risk assessment. Body weight, feed conversion ratio and feed intake decreased with increasing malathion dose. In addition to reduced feed intake, cold carcass and liver weights of the chicks were also decreased. The highest residues were found in the skin of the chicken followed by the breast, thigh, wing and liver. The TFs of malathion varied between 0.00 and 0.05 according to the different doses applied (4 mg/kg, 8 mg/kg, 16 mg/kg, 32 mg/kg). The chronic exposure assessment (HQ) showed that consumers of all ages and genders consumed 0.008-0.604% of the acceptable daily intake (0.3 mg/kg body weight (bw)/day) of malathion from chicken products. The acute intake assessment (aHQ) of consumers ranged from 0.00015 to 0.0135% of the acute reference dose (0.3 mg/kg bw). In conclusion the results suggest that the risk associated with the malathion residues in chicken meat was found to be low but the residue levels in meat should not be ignored.

20.
J Agric Food Chem ; 72(13): 6931-6941, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38514379

RESUMO

Tembotrione is a triketone herbicide widely used for broad-spectrum weed control in corn but not registered for use in wheat. A wide collection of spring, winter, and EMS-derived mutant lines of wheat was evaluated for their response to tembotrione treatment. Two winter wheat (WW) genotypes (WW-1 and WW-2) were found to be least sensitive to this herbicide, surviving >6 times the field recommended dose (92 g ai ha-1) compared to the most sensitive genotype (WW-24). Further, HPLC analysis using [14C] tembotrione suggested that both WW-1 and WW-2 metabolized tembotrione rapidly to nontoxic metabolites. Pretreatment with a P450 inhibitor (malathion) followed by tembotrione application increased the sensitivity of WW-1 and WW-2 genotypes to this herbicide, suggesting likely involvement of P450 enzymes in metabolizing tembotrione similar to corn. Overall, our results suggest that the genotypes WW-1 and WW-2 can potentially be used to develop tembotrione-resistant wheat varieties.


Assuntos
Herbicidas , Herbicidas/farmacologia , Herbicidas/metabolismo , Triticum/genética , Triticum/metabolismo , Cicloexanonas/farmacologia , Sulfonas/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Zea mays/metabolismo
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