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Plant Disease Aug 2022Meta-analysis was used to compare yield protection and nematode suppression provided by two seed-applied and two soil-applied nematicides against and on cotton across... (Meta-Analysis)
Meta-Analysis
Meta-analysis was used to compare yield protection and nematode suppression provided by two seed-applied and two soil-applied nematicides against and on cotton across 3 years and several trial locations in the U.S. Cotton Belt. Nematicides consisted of thiodicarb- and fluopyram-treated seed, aldicarb and fluopyram applied in furrow, and combinations of the seed treatments and soil-applied fluopyram. The nematicides had no effect on nematode reproduction or root infection but had a significant impact on seed cotton yield response ([Formula: see text]), with an average increase of 176 and 197 kg/ha relative to the nontreated control in and infested fields, respectively. However, because of significant variation in yield protection and nematode suppression by nematicides, five or six moderator variables (cultivar resistance [ only], nematode infestation level, nematicide treatment, application method, trial location, and growing season) were used depending on nematode species. In -infested fields, greater yield protection was observed with nematicides applied in furrow and with seed-applied + in-furrow than with solo seed-applied nematicide applications. Most notable of these in-furrow nematicides were aldicarb and fluopyram (>131 g/ha) with or without a seed-applied nematicide compared with thiodicarb. In -infested fields, moderator variables provided no further explanation of the variation in yield response produced by nematicides. Furthermore, moderator variables provided little explanation of the variation in nematode suppression by nematicides in and -infested fields. The limited explanation by the moderator variables on the field efficacy of nematicides in and -infested fields demonstrates the difficulty of managing these pathogens with nonfumigant nematicides across the U.S. Cotton Belt.
Topics: Aldicarb; Animals; Antinematodal Agents; Benzamides; Gossypium; Pyridines; Seeds; Soil; Tylenchoidea; United States
PubMed: 34978874
DOI: 10.1094/PDIS-07-21-1529-RE -
Luminescence : the Journal of... Feb 2022A novel double-windows fluorescence sensor for carbofuran (CF) detection was successfully developed based on rare-earth Eu,Tb-doped Y O @SiO -based molecularly imprinted...
A novel double-windows fluorescence sensor for carbofuran (CF) detection was successfully developed based on rare-earth Eu,Tb-doped Y O @SiO -based molecularly imprinted nanoparticles (MINs) with a multilayer core-shell structure. The recognition process of the MINs for CF was fairly fast and needed only ~8 min to reach a dynamic equilibrium. Interestingly, one fluorescence attenuation window was found with an increase in CF concentration (Q) from 0.1 to 10 μg ml and with a limit of detection (LOD) of 0.04 μg ml at 544 nm belonging to the Tb emission, as well as another fluorescence enhanced window within the CF concentration range 10-100 μg ml (LOD = 4 μg ml ) at 617 nm of Eu emission in the dispersed rare-earth-doped MIN colloidal aqueous solution. Luminescence resonance energy transfer from CF to Eu and an inner filter effect of CF towards Tb , as well from the two independent detection windows were clearly observed simultaneously. The competition experiment displayed hardly any marked interference during detection of CF following addition of its analogues (carbaryl, isoprocarb, aldicarb, methomyl, and etofenprox). Moreover, the MINs could also be applied to accurately detect CF in rhubarb and wolfberry samples with recoveries of 85.7-92.2%. This sensing system has high specific recognition and a wide detection range for CF and provides new opportunities for pesticide detection.
Topics: Carbofuran; Limit of Detection; Molecular Imprinting; Nanoparticles; Silicon Dioxide
PubMed: 34889024
DOI: 10.1002/bio.4177 -
The Journal of Biological Chemistry Jan 2022Complex biological functions within organisms are frequently orchestrated by systemic communication between tissues. In the model organism Caenorhabditis elegans, the...
Complex biological functions within organisms are frequently orchestrated by systemic communication between tissues. In the model organism Caenorhabditis elegans, the pharyngeal and body wall neuromuscular junctions are two discrete structures that control feeding and locomotion, respectively. Separate, the well-defined neuromuscular circuits control these distinct tissues. Nonetheless, the emergent behaviors, feeding and locomotion, are coordinated to guarantee the efficiency of food intake. Here, we show that pharmacological hyperactivation of cholinergic transmission at the body wall muscle reduces the rate of pumping behavior. This was evidenced by a systematic screening of the effect of the cholinesterase inhibitor aldicarb on the rate of pharyngeal pumping on food in mutant worms. The screening revealed that the key determinants of the inhibitory effect of aldicarb on pharyngeal pumping are located at the body wall neuromuscular junction. In fact, the selective stimulation of the body wall muscle receptors with the agonist levamisole inhibited pumping in a lev-1-dependent fashion. Interestingly, this response was independent of unc-38, an alpha subunit of the nicotinic receptor classically expressed with lev-1 at the body wall muscle. This implies an uncharacterized lev-1-containing receptor underpins this effect. Overall, our results reveal that body wall cholinergic transmission not only controls locomotion but simultaneously inhibits feeding behavior.
Topics: Aldicarb; Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Cholinesterase Inhibitors; Feeding Behavior; Levamisole; Neuromuscular Junction; Signal Transduction
PubMed: 34864060
DOI: 10.1016/j.jbc.2021.101466 -
Comparative Biochemistry and... Feb 2022Acetylcholinesterase (AChE; EC 3.1.1.7) from aquatic organisms have been used to evaluate the exposure of specimens to pesticides and heavy metals at sublethal levels in...
Acetylcholinesterase from the charru mussel Mytella charruana: kinetic characterization, physicochemical properties and potential as in vitro biomarker in environmental monitoring of mollusk extraction areas.
Acetylcholinesterase (AChE; EC 3.1.1.7) from aquatic organisms have been used to evaluate the exposure of specimens to pesticides and heavy metals at sublethal levels in environmental samples. AChE of Mytella charruana was extracted to characterize its physicochemical and kinetic properties as well as the effect of organophosphate (dichlorvos, diazinon, chlorpyrifos, methyl-parathion and temephos), carbamates (carbaryl, carbofuran and aldicarb), benzoylureas (diflubenzuron and novaluron), pyrethroid (cypermethrin) and juvenile hormone analog - JHA (pyriproxyfen) and the effect of metal ions: Hg, Cd, Pb, As, Cu and Zn, in order to evaluate the potential of the enzyme as biomarker. The optimum pH of M. charruana AChE was 8.5 and the maximum activity peak occurred at 48 °C, being highly thermostable maintaining 97.8% of its activity after incubation at 60 °C. The Michaelis-Menten constants (k) for the substrates acetylthiocholine and propionylthiocholine were 2.8 ± 1.26 and 4.94 ± 6.9 mmol·L, respectively. The V values for the same substrates were 22.6 ± 0.90 and 10.2 ± 4.94 mU·mg, respectively. Specific inhibition results suggest an AChE presenting active site with dimensions between those of AChE and butyrylcholinesterase (BChE). The IC values related to the effect of the pesticides on the enzyme showed higher inhibitory power of temephos (0.17 μmol·L), followed by aldicarb (0.19 μmol·L) and diflubenzuron (0.23 μmol·L). Metal ions inhibited M. charruana enzyme in the following order: Hg > Pb > Cd > As > Cu > Zn. These data suggest that the enzyme showed potential as in vitro biomarker of the exposure to temephos, mercury, zinc and copper.
Topics: Acetylcholinesterase; Animals; Biomarkers; Bivalvia; Environmental Monitoring; Gene Expression Regulation, Enzymologic; Metals, Heavy; Pesticides; Water Pollutants, Chemical
PubMed: 34744030
DOI: 10.1016/j.cbpc.2021.109225 -
Annals of Neurosciences Jan 2021Alzheimer's disease (AD), a prevalent neurodegenerative disease with progressive dementia and neurotransmission (NT)-dysfunction-related complications in older adults,...
BACKGROUND
Alzheimer's disease (AD), a prevalent neurodegenerative disease with progressive dementia and neurotransmission (NT)-dysfunction-related complications in older adults, is known to be caused by abnormal Amyloid-β (Aβ) peptide and associated amyloid plaques in the brain. Drugs to cure AD are not in sight. Two major excitatory neurotransmitters, glutamate (Glu) and acetylcholine (ACh), and their signaling systems are implicated in AD.
OBJECTIVE
To determine the effect of various NT-altering compounds including fenobam, quisqualic acid, and dimethyl sulfoxide (DMSO) in the protection against Aβ toxicity. Further, to identify the potential mechanism through which the protection happens.
METHODS
The well-known AD model, CL4176, in which human Aβ expression is turned on upon a temperature shift to 25 °C that leads to paralysis, was screened for protection/delay in paralysis because of Αβ toxicity. While screening the compounds, dimethyl sulfoxide (DMSO), a universal solvent used to solubilize compounds, was identified to provide protection. Aldicarb and levamisole assays were performed to identify the contribution of ACh neurotransmission in Αβ toxicity protection by DMSO.
RESULTS
One percent and two percent DMSO delayed paralysis by 48% and 90%, respectively. DMSO was dominant over one of the Glu-NT pathway-related compounds, Fenobam-Group I mGluR antagonist. But DMSO provided only 30% to 50% protection against Quisqualic acid, the Glu-agonist. DMSO (2%) delayed ACh-NT, both presynaptic acetylcholine esterase inhibitor (AchEi)-aldicarb and postsynaptic-iAChR-agonst-levamisole induced paralysis, by ∼70% in CL4176. DMSO seems to be altering Ca ion permeability essential for NT as EthyleneDiamine Tetra-Acetic acid (EDTA) and DMSO provided similar aldicarb resistance either combined or alone in wildtype worms. But postsynaptic Ca depletion by EDTA could reverse DMSO-induced levamisole hypersensitivity. Surprisingly, the absence of FOrkhead boXO (FOXO) transcription factor homolog, (loss-of-function mutant), a critical transcription factor in the reduced IIS-mediated longevity in abolished DMSO-mediated Ald.
CONCLUSION
DMSO and Fenobam protect against Aβ toxicity through modulation of NT.
PubMed: 34733055
DOI: 10.1177/09727531211046369 -
Toxics Oct 2021Animal poisoning is one of the greatest conservation threats facing wildlife. In a preliminary study in the oceanic archipelago of the Canary Islands, we showed that the...
Animal poisoning is one of the greatest conservation threats facing wildlife. In a preliminary study in the oceanic archipelago of the Canary Islands, we showed that the degree of threat from this circumstance was very high-even higher than that reported in other regions of continental Europe. Consequently, a legal framework for the effective prosecution of the crime of wildlife poisoning came into force in 2014 in this region. We present the results of the investigation of 961 animals and 84 baits sent to our laboratory for the diagnosis of animal poisonings during the period 2014-2021. We were able to identify poison as the cause of death in 251 animals and 61 baits. Carbofuran stands out as the main agent used in this archipelago. We have also detected an increasing tendency to use mixtures of several pesticides in the preparation of baits. The entry into operation of two canine patrols has led to the detection of more dead animals in the wild and a greater number of poisoned animals. The percentage of poison positives is significantly higher in areas with lower population density, corresponding to rural environments, as well as in areas with greater agricultural and livestock activity.
PubMed: 34678963
DOI: 10.3390/toxics9100267 -
Human Molecular Genetics Mar 2022Dominant GNAO1 mutations cause an emerging group of childhood-onset neurological disorders characterized by developmental delay, intellectual disability, movement...
Dominant GNAO1 mutations cause an emerging group of childhood-onset neurological disorders characterized by developmental delay, intellectual disability, movement disorders, drug-resistant seizures and neurological deterioration. GNAO1 encodes the α-subunit of an inhibitory GTP/GDP-binding protein regulating ion channel activity and neurotransmitter release. The pathogenic mechanisms underlying GNAO1-related disorders remain largely elusive and there are no effective therapies. Here, we assessed the functional impact of two disease-causing variants associated with distinct clinical features, c.139A > G (p.S47G) and c.662C > A (p.A221D), using Caenorhabditis elegans as a model organism. The c.139A > G change was introduced into the orthologous position of the C. elegans gene via CRISPR/Cas9, whereas a knock-in strain carrying the p.A221D variant was already available. Like null mutants, homozygous knock-in animals showed increased egg laying and were hypersensitive to aldicarb, an inhibitor of acetylcholinesterase, suggesting excessive neurotransmitter release by different classes of motor neurons. Automated analysis of C. elegans locomotion indicated that goa-1 mutants move faster than control animals, with more frequent body bends and a higher reversal rate and display uncoordinated locomotion. Phenotypic profiling of heterozygous animals revealed a strong hypomorphic effect of both variants, with a partial dominant-negative activity for the p.A221D allele. Finally, caffeine was shown to rescue aberrant motor function in C. elegans harboring the goa-1 variants; this effect is mainly exerted through adenosine receptor antagonism. Overall, our findings establish a suitable platform for drug discovery, which may assist in accelerating the development of new therapies for this devastating condition, and highlight the potential role of caffeine in controlling GNAO1-related dyskinesia.
Topics: Acetylcholinesterase; Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Caffeine; Drug Evaluation, Preclinical; Dyskinesias; GTP-Binding Protein alpha Subunits, Gi-Go; GTP-Binding Proteins; Mutation; Neurotransmitter Agents
PubMed: 34622282
DOI: 10.1093/hmg/ddab296 -
IUBMB Life Jul 2022Riboflavin (Rf), or vitamin B2, is the precursor of FMN and FAD, redox cofactors of several dehydrogenases involved in energy metabolism, redox balance and other cell...
Riboflavin (Rf), or vitamin B2, is the precursor of FMN and FAD, redox cofactors of several dehydrogenases involved in energy metabolism, redox balance and other cell regulatory processes. FAD synthase, coded by FLAD1 gene in humans, is the last enzyme in the pathway converting Rf into FAD. Mutations in FLAD1 gene are responsible for neuromuscular disorders, in some cases treatable with Rf. In order to mimic these disorders, the Caenorhabditis elegans (C. elegans) gene orthologue of FLAD1 (flad-1) was silenced in a model strain hypersensitive to RNA interference in nervous system. Silencing flad-1 resulted in a significant decrease in total flavin content, paralleled by a decrease in the level of the FAD-dependent ETFDH protein and by a secondary transcriptional down-regulation of the Rf transporter 1 (rft-1) possibly responsible for the total flavin content decrease. Conversely an increased ETFDH mRNA content was found. These biochemical changes were accompanied by significant phenotypical changes, including impairments of fertility and locomotion due to altered cholinergic transmission, as indicated by the increased sensitivity to aldicarb. A proposal is made that neuronal acetylcholine production/release is affected by alteration of Rf homeostasis. Rf supplementation restored flavin content, increased rft-1 transcript levels and eliminated locomotion defects. In this aspect, C. elegans could provide a low-cost animal model to elucidate the molecular rationale for Rf therapy in human Rf responsive neuromuscular disorders and to screen other molecules with therapeutic potential.
Topics: Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Disease Models, Animal; Flavin-Adenine Dinucleotide; Humans; Neuromuscular Diseases; Nucleotidyltransferases; Riboflavin; Vitamins
PubMed: 34558787
DOI: 10.1002/iub.2553 -
Ecotoxicology and Environmental Safety Aug 2021Carbaryl is the representative of carbamate insecticide. As an acetylcholinesterase inhibitor, it poses potential threat to humans and other non-target organisms....
Carbaryl is the representative of carbamate insecticide. As an acetylcholinesterase inhibitor, it poses potential threat to humans and other non-target organisms. Agrobacterium sp. XWY-2, which could grow with carbaryl as the sole carbon source, was isolated and characterized. The carH gene, encoding a carbaryl hydrolase, was cloned from strain XWY-2 and expressed in Escherichia coli BL21 (DE3). CarH was able to hydrolyze carbamate pesticides including carbaryl, carbofuran, isoprocarb, propoxur and fenobucarb efficiently, while it hydrolyzed oxamyl and aldicarb poorly. The optimal pH of CarH was 8.0 and the optimal temperature was 30 ℃. The apparent K and k values of CarH for carbaryl were 38.01 ± 2.81 μM and 0.33 ± 0.01 s, respectively. The point mutation experiment demonstrated that His341, His343, His346, His416 and D437 are the key sites for CarH to hydrolyze carbaryl.
PubMed: 34416635
DOI: 10.1016/j.ecoenv.2021.112666 -
Ecotoxicology and Environmental Safety Aug 2021Studies investigating the association between pesticide exposure and colorectal cancer (CRC) risk have been inconclusive.
BACKGROUND
Studies investigating the association between pesticide exposure and colorectal cancer (CRC) risk have been inconclusive.
OBJECTIVES
Investigate the association between pesticide exposure and CRC risk through a systematic literature review.
METHODS
CRC has the fourth-highest rate of cancer-caused death in the US after lung cancer, breast cancer in women, and prostate cancer in men. Here we have conducted a systematic literature search on studies examining the association between any pesticide exposure and CRC risk using PubMed, MEDLINE via EBSCO host, and Embase according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist.
RESULTS
Following the review, 139 articles were included for qualitative evaluation. Study participants were farmers, pesticide applicators, pesticide manufacturers, spouses of pesticide applicators, farm residents, Korean veterans of the Vietnam War, rural communities, and those who consumed food with pesticide residues. The studies' results were split between those with significant positive (39 significant results) and inverse (41 significant results) associations when comparing pesticide exposure and CRC risk.
DISCUSSION
From our literature review, we have identified a similar number of significant positive and inverse associations of pesticide exposure with CRC risk and therefore cannot conclude whether pesticide exposure has a positive or inverse association with CRC risk overall. However, certain pesticides such as terbufos, dicamba, trifluralin, S-ethyl dipropylthiocarbamate (EPTC), imazethapyr, chlorpyrifos, carbaryl, pendimethalin, and acetochlor are of great concern not only for their associated elevated risk of CRC, but also for the current legal usage in the United States (US). Aldicarb and dieldrin are of moderate concern for the positive associations with CRC risk, and also for the illegal usage or the detection on imported food products even though they have been banned in the US. Pesticides can linger in the soil, water, and air for weeks to years and, therefore, can lead to exposure to farmers, manufacturing workers, and those living in rural communities near these farms and factories. Approximately 60 million people in the US live in rural areas and all of the CRC mortality hotspots are within the rural communities. The CRC mortality rate is still increasing in the rural regions despite the overall decreasing of incidence and mortality of CRC elsewhere. Therefore, the results from this study on the relationship between pesticide exposure and CRC risk will help us to understand CRC health disparities.
Topics: Adult; Colorectal Neoplasms; Farmers; Female; Herbicides; Humans; Incidence; Male; Middle Aged; Occupational Exposure; Pesticide Residues; Pesticides
PubMed: 34029839
DOI: 10.1016/j.ecoenv.2021.112327