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Analytica Chimica Acta: X Nov 2021In this study, cobalt nanoparticles (CoNPs) were synthesized and cobalt nanoparticles modified glassy carbon electrode (CoNPs/GCE) was prepared by drop coating the...
In this study, cobalt nanoparticles (CoNPs) were synthesized and cobalt nanoparticles modified glassy carbon electrode (CoNPs/GCE) was prepared by drop coating the nanoparticles on glassy carbon electrode. After preparing polypyrrole modified glassy carbon electrode (PPy/GCE) using electropolymerization of pyrrole in LiClO solution, cobalt nanoparticles-polypyrrole composite modified glassy carbon electrode (CoNPs/PPy/GCE) was fabricated by drop coating the CoNPs on the PPy/GCE. Different characterization techniques such as scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, FTIR spectroscopy, electrochemical impedance spectroscopy and cyclic voltammetry were used to study the morphological structure and electrochemical behavior of the sensors. The results demonstrated that PPy chains interacted with CoNPs through donor-acceptor bonds. Among all the electrodes, CoNPs/PPy/GCE exhibited highest electroactive surface area and lowest electron transfer resistance towards phoxim. Under the optimal conditions, the sensor showed linear relationship between the reduction peak current and the concentration of phoxim in the range of 0.025 μM-12 μM with the detection limit as 4.5 nM. Besides, the composite electrode demonstrated excellent reproducibility, good stability and selectivity towards the possible interfering substances. All of these properties made CoNPs/PPy/GCE a suitable electrochemical sensor for the electrochemical determination of phoxim in water samples using square wave voltammetry.
PubMed: 34622198
DOI: 10.1016/j.acax.2021.100077 -
Foods (Basel, Switzerland) Jul 2021A novel sorbent based on the ZrO nanoparticles and poly(diallyldimethylammonium chloride)-modified graphene oxide aerogel-grafted stainless steel mesh (ZrO/PDDA-GOA-SSM)...
ZrO Nanoparticles and Poly(diallyldimethylammonium chloride)-Doped Graphene Oxide Aerogel-Coated Stainless-Steel Mesh for the Effective Adsorption of Organophosphorus Pesticides.
A novel sorbent based on the ZrO nanoparticles and poly(diallyldimethylammonium chloride)-modified graphene oxide aerogel-grafted stainless steel mesh (ZrO/PDDA-GOA-SSM) was used for the extraction and detection of organophosphorus pesticides (OPPs). Firstly, the PDDA and GO composite was grafted onto the surface of SSM and then freeze-dried to obtain the aerogel, which efficiently reduced the accumulation of graphene nanosheets. It integrated the advanced properties of GOA with a thin coating and the three-dimensional structural geometry of SSM. The modification of ZrO nanoparticles brought a selective adsorption for OPPs due to the combination of the phosphate group as a Lewis base and ZrO nanoparticles with the Lewis acid site. The ZrO/PDDA-GOA-SSM was packed into the solid-phase extraction (SPE) cartridge to extract OPPs. According to the investigation of different factors, the extraction recovery was mainly affected by the hydrophilic-hydrophobic properties of analytes. Effective extraction and elution parameters such as sample volume, sample pH, rate of sample loading, eluent, and eluent volume, were also investigated and discussed. Under the optimal conditions, the linearity of phoxim and fenitrothion was in the range of 1.0-200 μg L, and the linearity of temephos was in the range of 2.5-200 μg L. The limits of detection were ranged from 0.2 to 1.0 μg L. This established method was successfully applied to detect OPPs in two vegetables. There was no OPP detected in real samples, and results showed that the matrix effects were in the range of 46.5%-90.1%. This indicates that the ZrO/PDDA-GOA-SSM-SPE-HPLC method could effectively extract and detect OPPs in vegetables.
PubMed: 34359486
DOI: 10.3390/foods10071616 -
Insects Jul 2021With the widespread application of insecticides, parasitoid wasps may also be under risk when exposed to insecticides directly at their free-living stages. The...
With the widespread application of insecticides, parasitoid wasps may also be under risk when exposed to insecticides directly at their free-living stages. The endoparasitoid wasp is the predominant natural enemy of many lepidopteran pests, such as and . The cytochrome P450 monooxygenases constitute a ubiquitous and complex superfamily of hydrophobic, haem-containing enzymes. P450s are involved in the detoxification of many xenobiotics. However, their exact roles in the tolerance mechanism in parasitoids toward insecticides has received less attention. Here, 28 P450 genes in were identified from a previously constructed transcriptome dataset. These P450 genes belonged to CYP2, -3, and -4, and mitochondrial clans. Subsequently, eight candidate were selected from four CYP clans to validate their expression patterns under phoxim, cypermethrin, and chlorfenapyr exposure by qRT-PCR. The results showed that all three insecticides had significant effects on the expression of . To further study the function of P450s, was silenced, and its expression levels of were significantly decreased. Survival analysis indicated that after dsRNA injection, the mortality rate of wasps was significantly increased when females were exposed to insecticides compared to control groups. Our findings provide a theoretical base for elucidating the mechanism of insecticide tolerance and promote functional research on P450 genes in parasitoid wasps.
PubMed: 34357311
DOI: 10.3390/insects12070651 -
Medicine Jun 2021Acute organophosphorus pesticide poisoning (AOPP) is a common critical illness observed in clinical practice, and severe AOPP can cause serious cardiac toxicity.
RATIONALE
Acute organophosphorus pesticide poisoning (AOPP) is a common critical illness observed in clinical practice, and severe AOPP can cause serious cardiac toxicity.
PATIENT CONCERNS
This patient was a 43-year-old woman who was admitted to the emergency department with acute respiratory failure and hypotension 13 hours after oral consumption of 300 mL of phoxim pesticide.
DIAGNOSES
Acute organophosphorus pesticide poisoning, cardiogenic shock.
INTERVENTIONS
We conducted veno-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy as the patient did not respond to conventional measures.
OUTCOMES
This patient was successfully rescued with VA-ECMO therapy and discharged.
LESSONS
We suggest that for patients with severe myocardial injury complicated with cardiogenic shock caused by AOPP, the use of VA-ECMO therapy can improve the prognosis.
Topics: Adult; Cardiotoxicity; Electrocardiography; Extracorporeal Membrane Oxygenation; Female; Humans; Organophosphate Poisoning; Organophosphates; Pesticides; Shock, Cardiogenic; Treatment Outcome
PubMed: 34115044
DOI: 10.1097/MD.0000000000026318 -
Journal of Insect Science (Online) Jan 2021Insecticides can have consequences for beneficial arthropods. Insect parasitoids can contact insecticides through direct exposure spray droplets or residues on crop...
Evaluation of Sensitivity to Phoxim and Cypermethrin in an Endoparasitoid, Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae), and Its Parasitization Efficiency Under Insecticide Stress.
Insecticides can have consequences for beneficial arthropods. Insect parasitoids can contact insecticides through direct exposure spray droplets or residues on crop foliage. Here, we focus on better understand the response of Meteorus pulchricornis (Wesmael), a parasitoid wasp of lepidopteran pests, and its detoxification mechanisms on stress caused by phoxim and cypermethrin. Hence, we determined the dose-mortality curves and estimating the sublethal concentrations (LC30 and LC50). Then, we applied the sublethal concentrations against adult parasitoids to assess its survival, parasitism efficacy, and also developmental and morphometric parameters of their offspring. Simultaneously, we check the activities of glutathione S-transferase (GST), acetylcholinesterase (AChE), and peroxidase (POD) after sublethal exposure of both insecticides, which has measured until 48 h after treatment. Overall, phoxim and cypermethrin exhibited acute lethal activity toward the parasitoid with LC50 values 4.608 and 8.570 mg/liter, respectively. Also, we detect that LC30 was able to trigger the enzymatic activity of GST, AChE, and POD, suggesting a potential detoxification mechanism. However, even when subjected to sublethal exposure, our results indicate strong negatives effects, in particular for phoxim, which has affected the parasitism efficacy and also the developmental and morphometric parameters of M. pulchricornis offspring. Therefore, it can be concluded that both phoxim and cypermethrin have negative impacts on M. pulchricornis and we suggest cautioning their use and the need for semifield and field assessments to confirm such an impact.
Topics: Animals; Host-Parasite Interactions; Insecticides; Organothiophosphorus Compounds; Pyrethrins; Spodoptera; Wasps
PubMed: 33580255
DOI: 10.1093/jisesa/ieab002 -
International Journal of Molecular... Jun 2020YC-XJ1 isolated from desert soil exhibited a diverse degrading ability towards aromatic oxyphenoxypropionic acid esters (AOPPs) herbicide, phthalate esters (PAEs),...
YC-XJ1 isolated from desert soil exhibited a diverse degrading ability towards aromatic oxyphenoxypropionic acid esters (AOPPs) herbicide, phthalate esters (PAEs), organophosphorus flame retardants (OPFRs), chlorpyrifos and phoxim. The genome of YC-XJ1 was sequenced and analyzed systematically. YC-XJ1 contained a large number of exogenous compounds degradation pathways and hydrolase resources. The quizalofop-p-ethyl (QPE) degrading gene and diethyl phthalate (DEP) degrading gene were cloned and expressed. The characteristics of corresponding hydrolases were investigated. The specific activity of recombinant QPEH2 was 0.1 ± 0.02 U mg for QPE with / values of 1.8 ± 0.016 (mM·s). The specific activity of recombinant DEPH1 was 0.1 ± 0.02 U mg for DEP with / values of 0.8 ± 0.02 (mM·s). This work systematically illuminated the metabolic versatility of strain YC-XJ1 via the combination of genomics analysis and laboratory experiments. These results suggested that strain YC-XJ1 with diverse xenobiotics biodegrading capacity was a promising candidate for the bioremediation of polluted sites.
Topics: Amino Acid Sequence; Biodegradation, Environmental; DNA, Bacterial; Genome, Bacterial; Hydrolases; Methylobacteriaceae; Phylogeny; Sequence Homology; Soil Microbiology; Xenobiotics
PubMed: 32580446
DOI: 10.3390/ijms21124436 -
Scientific Reports May 2020Two unique housefly strains, PSS and N-PRS (near-isogenic line with the PSS), were used to clarify the mechanisms associated with propoxur resistance in the housefly,...
Two unique housefly strains, PSS and N-PRS (near-isogenic line with the PSS), were used to clarify the mechanisms associated with propoxur resistance in the housefly, Musca domestica. The propoxur-selected resistant (N-PRS) strain exhibited >1035-fold resistance to propoxur and 1.70-, 12.06-, 4.28-, 57.76-, and 57.54-fold cross-resistance to beta-cypermethrin, deltamethrin, bifenthrin, phoxim, and azamethiphos, respectively, compared to the susceptible (PSS) strain. We purified acetylcholinesterase (AChE) from the N-PRS and PSS strains using a procainamide affinity column and characterized the AChE. The sensitivity of AChE to propoxur based on the bimolecular rate constant (K) was approximately 100-fold higher in the PSS strain compared to the N-PRS strain. The cDNA encoding Mdace from both the N-PRS strain and the PSS strain were cloned and sequenced using RT-PCR. The cDNA was 2073 nucleotides long and encoded a protein of 691 amino acids. A total of four single nucleotide polymorphisms (SNPs), I162M, V260L, G342A, and F407Y, were present in the region of the active site of AChE from the N-PRS strain. The transcription level and DNA copy number of Mdace were significantly higher in the resistant strain than in the susceptible strain. These results indicated that mutations combined with the up-regulation of Mdace might be essential in the housefly resistance to propoxur.
Topics: Acetylcholinesterase; Animals; Cholinesterase Inhibitors; Gene Expression Regulation, Enzymologic; Houseflies; Insect Proteins; Insecticide Resistance; Insecticides; Mutation; Polymorphism, Single Nucleotide; Propoxur
PubMed: 32439946
DOI: 10.1038/s41598-020-65242-3 -
International Journal of Molecular... Jan 2020The existence of a temperature effect of insecticides frustrated the control of the green plant bug (Meyer-Dür). Previous studies mostly focused on the application of... (Comparative Study)
Comparative Study
The existence of a temperature effect of insecticides frustrated the control of the green plant bug (Meyer-Dür). Previous studies mostly focused on the application of insecticides, but the underlying mechanism remains incompletely understood. Here, we report a transcriptome profiling of treated by three kinds of temperature coefficient insecticides (TCIs) (positive TCI: imidacloprid, negative TCI: b-cypermethrin and non-effect TCI: phoxim) at 15 °C, 25 °C and 35 °C by using next- and third-generation RNA-Seq methods. A total of 34,739 transcripts were annotated from 277.74 Gb of clean data. There were more up-regulated transcripts than down-regulated transcripts in all three kinds of TCI treatments. Further Venn diagrams indicate the regulatory transcripts and regulatory modes were different at the three temperatures. The responses to imidacloprid involved more detox and stress response transcripts such as cytochrome P450 (CYP450), carboxylesterase (CarE) and catalase (CAT) at 35 °C, which was the case for beta-cypermethrin at 15 °C. UDP-glucuronyltransferase (UGT) and heat shock protein (HSP) transcripts were heavily involved, and thus deserve particular note in the temperature effect of insecticides. This high-confidence transcriptome atlas provides improved gene information for further study on the insecticide temperature effect related physiological and biochemical processes of .
Topics: Animals; Gene Expression Profiling; Gene Expression Regulation; Heteroptera; High-Throughput Nucleotide Sequencing; Insect Proteins; Insecticides; Molecular Sequence Annotation; Neonicotinoids; Nitro Compounds; Organothiophosphorus Compounds; Pyrethrins; Sequence Analysis, RNA; Temperature
PubMed: 31963875
DOI: 10.3390/ijms21020658 -
Molecules (Basel, Switzerland) Nov 2019Phoxim, a type of organophosphorus pesticide (OP), is widely used in both agriculture and fisheries. The persistence of phoxim has caused serious environmental pollution...
Phoxim, a type of organophosphorus pesticide (OP), is widely used in both agriculture and fisheries. The persistence of phoxim has caused serious environmental pollution problems. In this study, YP6 (YP6), which is capable of promoting plant growth and degrading broad-spectrum OPs, was used to study phoxim degradation. Different culture media were applied to evaluate the growth and phoxim degradation of YP6. YP6 can grow rapidly and degrade phoxim efficiently in Luria-Bertani broth (LB broth) medium. Furthermore, it can also utilize phoxim as the sole phosphorus source in a mineral salt medium. Response surface methodology was performed to optimize the degradation conditions of phoxim by YP6 in LB broth medium. The optimum biodegradation conditions were 40 °C, pH 7.20, and an inoculum size of 4.17% (/). The phoxim metabolites, ,-diethylthiophosphoric ester, phoxom, and α-cyanobenzylideneaminooxy phosphonic acid, were confirmed by liquid chromatography-mass spectrometry. Meanwhile, transcriptome analysis and qRT-PCR were performed to give insight into the phoxim-stress response at the transcriptome level. The hydrolase-, oxidase-, and NADPH-cytochrome P450 reductase-encoding genes were significantly upregulated for phoxim hydrolysis, sulfoxidation, and o-dealkylation. Furthermore, the phoxim biodegradation pathways by YP6 were proposed, for the first time, based on transcriptomic data and product analysis.
Topics: Bacillus amyloliquefaciens; Biodegradation, Environmental; Genes, Bacterial; Hydrogen-Ion Concentration; Hydrolysis; NADPH-Ferrihemoprotein Reductase; Organothiophosphorus Compounds; Pesticides; Transcriptome
PubMed: 31694203
DOI: 10.3390/molecules24213997 -
International Journal of Molecular... Aug 2019Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductases (CPRs) function as redox partners of cytochrome P450 monooxygenases (P450s). CPRs and...
Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductases (CPRs) function as redox partners of cytochrome P450 monooxygenases (P450s). CPRs and P450s in insects have been found to participate in insecticide resistance. However, the CPR of the moth has not been well characterized yet. Based on previously obtained transcriptome information, a full-length CPR cDNA of () was PCR-cloned. The deduced amino acid sequence contains domains and residues predicted to be essential for CPR function. Phylogenetic analysis with insect CPR amino acid sequences showed that is closely related to CPRs of Lepidoptera. Quantitative reverse transcriptase PCR (RT-qPCR) was used to determine expression levels of in different developmental stages and tissues of . expression was strongest at the sixth-instar larvae stage and fifth-instar larvae showed highest expression in the midgut. Expression of in the midgut and fat body was strongly upregulated when fifth-instar larvae were exposed to phoxim at LC (4 μg/mL) and LC (20 μg/mL) doses. RNA interference (RNAi) mediated silencing of increased larval mortality by 34.6% (LC dose) and 53.5% (LC dose). Our results provide key information on the gene and indicate that expression levels in larvae influence their susceptibility to phoxim and possibly other insecticides.
Topics: Amino Acid Sequence; Animals; Gene Expression Regulation; Gene Silencing; Insecticide Resistance; Insecticides; Larva; NADPH-Ferrihemoprotein Reductase; Organothiophosphorus Compounds; Phylogeny; RNA Interference; Spodoptera
PubMed: 31390813
DOI: 10.3390/ijms20153839