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ACS Omega Feb 2022Graphene-enhanced Raman scattering (GERS) produces enhancement of the Raman signal, which is based on chemical rather than electromagnetic mechanism such as in the...
Graphene-enhanced Raman scattering (GERS) produces enhancement of the Raman signal, which is based on chemical rather than electromagnetic mechanism such as in the surface-enhanced Raman scattering. Graphene oxide, amino- and guanidine-functionalized graphene oxide, exfoliated graphene, and commercial graphene nanoplatelets have been used to investigate the GERS response with the change of graphene properties. Different graphene nanostructures have been embedded into organic-inorganic microporous films to build a platform for the fast and sensitive detection of pesticides in water. The graphene nanostructures vary in the number of layers, lateral size, degree of oxidation, and surface functionalization. The GERS performances of the graphene nanostructures cast on silicon substrates and embedded in the nanocomposite films have been comparatively evaluated. After casting a few droplets of the pesticide aqueous solution on the graphene nanostructures, the Raman band enhancements of the analytes have been measured. In the nanocomposite films, the characteristic Raman bands originating from pesticides such as paraoxon, parathion, and glyphosate could be traced at concentrations below 10, 10, and 10 M, respectively. The results show that the surface functionalization reduces the GERS effect because it increases the ratio between the sp carbon and sp carbon. On the other hand, the comparison among different types of graphenes shows that the monolayers are more efficient than the few-layer nanostructures in enhancing the Raman signal.
PubMed: 35224328
DOI: 10.1021/acsomega.1c04863 -
Frontiers in Microbiology 2022Organophosphate compounds are widely used in pesticides to control weeds, crop diseases, and insect pests. Unfortunately, these synthetic compounds are hazardous and...
Organophosphate compounds are widely used in pesticides to control weeds, crop diseases, and insect pests. Unfortunately, these synthetic compounds are hazardous and toxic to all types of living organisms. In the present work, was bioengineered to achieve methyl parathion (MP) degradation via the introduction of six synthetic genes, namely, , , , , , and , to obtain a new transformant, BL-MP. MP and its subsequent decomposition intermediates were completely degraded by this transformant to enter the metabolites of multiple anabolic pathways. The MP-degraded strain created in this study may be a promising candidate for the bioremediation of MP and potential toxic intermediates.
PubMed: 35222319
DOI: 10.3389/fmicb.2022.679126 -
Movement Disorders : Official Journal... May 2022Dream-enacting behavior is a characteristic feature of rapid eye movement sleep behavior disorder, the most specific prodromal marker of synucleinopathies. Pesticide...
BACKGROUND
Dream-enacting behavior is a characteristic feature of rapid eye movement sleep behavior disorder, the most specific prodromal marker of synucleinopathies. Pesticide exposure may be associated with dream-enacting behaviors, but epidemiological evidence is limited.
OBJECTIVES
To examine high pesticide exposure events in relation to dream-enacting behaviors among farmers in the Agricultural Health Study.
METHODS
We conducted multivariable logistic regression analyses to examine high pesticide exposure events reported from 1993 to 1997 in relation to dream-enacting behaviors assessed from 2013 to 2015 among 11,248 farmers (age 47 ± 11 years).
RESULTS
A history of dream-enacting behaviors was reported by 939 (8.3%) farmers. Compared with farmers who did not report any high pesticide exposure event, those who reported were more likely to endorse dream-enacting behaviors 2 decades later (odds ratio = 1.75; 95% confidence interval [CI], 1.49-2.05). The association appeared stronger when there was a long delay in washing with soap and water after the event (2.63 [95% CI, 1.62-4.27] for waiting >6 hours vs. 1.71 [95% CI, 1.36-2.15] for washing within 30 minutes) and when the exposure involved the respiratory or digestive tract (2.04 [95% CI, 1.62-2.57] vs. 1.58 [95% CI, 1.29-1.93] for dermal contact only). In the analyses of specific pesticides involved, we found positive associations with two organochlorine insecticides (dichlorodiphenyltrichloroethane and lindane), four organophosphate insecticides (phorate, ethoprop, terbufos, and parathion), two herbicides (alachlor and paraquat), and fungicides as a group.
CONCLUSIONS
This study provides the first epidemiological evidence that high pesticide exposures may be associated with a higher risk of dream-enacting behaviors. © 2022 International Parkinson and Movement Disorder Society.
Topics: Adult; Agriculture; Farmers; Humans; Insecticides; Middle Aged; Occupational Exposure; Pesticides
PubMed: 35152487
DOI: 10.1002/mds.28960 -
Journal of Dairy Science Apr 2022As a food adapted to all kinds of people, milk has a high nutritional value. Because milk is a complex biological matrix, detecting illegal compounds is often difficult....
As a food adapted to all kinds of people, milk has a high nutritional value. Because milk is a complex biological matrix, detecting illegal compounds is often difficult. As a common pesticide, organophosphorus (OP) residues caused by nonstandard use may be ignored, which is a threat to milk quality. In this study, using coumaphos as template molecule, the synthesized molecularly imprinted polymer (MIP) can specifically recognize 7 kinds of OP. Then, the MIP was used as an identification element to prepare a chemiluminescence sensor on a 96-well microplate for the determination of OP residues in milk samples. Due to the 4-(imidazol-1-yl)phenol-enhanced luminol-HO system, the sensitivity of the system is very high; the detection limits of 7 OP including coumaphos, fenthion, chlorpyrifos, parathion, diazinon, fenchlorphos, and fenitrothion were 1 to 3 pg/mL, and the half maximal inhibitory concentrations were 1 to 20 ng/mL. The intraday recoveries of 7 OP were in the range of 86.1 to 86.5%, and the interday recoveries were in the range of 83.6 to 94.2%. Furthermore, the sensor can be reused up to 5 times. Therefore, the MIP-based chemiluminescence sensor can be used as a routine tool to detect OP residues in milk samples.
Topics: Animals; Humans; Hydrogen Peroxide; Luminescence; Milk; Molecular Imprinting; Molecularly Imprinted Polymers; Polymers
PubMed: 35086700
DOI: 10.3168/jds.2021-21213 -
British Journal of Clinical Pharmacology Dec 2022Organophosphorus (OP) insecticide poisoning causes respiratory failure due to acetylcholinesterase (AChE) inhibition. The AChE reactivating antidote pralidoxime was...
Organophosphorus (OP) insecticide poisoning causes respiratory failure due to acetylcholinesterase (AChE) inhibition. The AChE reactivating antidote pralidoxime was developed in the 1950s and was soon noted to benefit patients occupationally poisoned with the highly potent OP insecticide parathion. Routine use of pralidoxime and other oximes such as obidoxime then became widely recommended. However, nearly all severe cases of OP poisoning now result from self-poisoning with large volumes of less potent (WHO hazard class Ib and II) insecticides and co-formulated solvents. Unfortunately, oxime clinical trials have never shown benefit from their use for these patients, and some have shown that pralidoxime may be associated with harm, including increased mortality. Oximes should not be used routinely for the care of OP insecticide-poisoned patients until translational and clinical studies have identified a safe and effective oxime regimen and identified the patients who benefit.
Topics: Humans; Insecticides; Oximes; Acetylcholinesterase; Organophosphorus Compounds; Organophosphate Poisoning; Cholinesterase Inhibitors; Poisoning
PubMed: 34989015
DOI: 10.1111/bcp.15217 -
Children (Basel, Switzerland) Nov 2021Brain tumors are the second most common neoplasm in the pediatric age. Pesticides may play an etiologic role, but literature results are conflicting. This review... (Review)
Review
Parental Pesticide Exposure and Childhood Brain Cancer: A Systematic Review and Meta-Analysis Confirming the IARC/WHO Monographs on Some Organophosphate Insecticides and Herbicides.
BACKGROUND
Brain tumors are the second most common neoplasm in the pediatric age. Pesticides may play an etiologic role, but literature results are conflicting. This review provides a systematic overview, meta-analysis, and IARC/WHO consideration of data on parental exposure to pesticides and childhood brain tumors.
METHODS
We searched PubMed, SCOPUS, and Google Scholar for literature (1 January 1966-31 December 2020) that assessed childhood brain tumors and parental exposure to pesticides. We undertook a meta-analysis addressing prenatal exposure, exposure after birth, occupational exposure, and residential exposure. A total of 130 case-control investigations involving 43,598 individuals (18,198 cases and 25,400 controls) were included.
RESULTS
Prenatal exposure is associated with childhood brain tumors (odds ratio, OR = 1.32; 95% CI: 1.17-1.49; I = 41.1%). The same occurs after birth exposure (OR = 1.22; 95% CI: 1.03-1.45, I = 72.3%) and residential exposure to pesticides (OR = 1.31; 95% CI: 1.11-1.54, I = 67.2%). Parental occupational exposure is only marginally associated with CBT (OR = 1.17, 95% CI: 0.99-1.38, I = 67.0%).
CONCLUSIONS
There is an association between CBT and parental pesticides exposure before childbirth, after birth, and residential exposure. It is in line with the IARC Monograph evaluating the carcinogenicity of diazinon, glyphosate, malathion, parathion, and tetrachlorvinphos.
PubMed: 34943292
DOI: 10.3390/children8121096 -
Applied and Environmental Microbiology Feb 2022The marine environment presents great potential as a source of microorganisms that possess novel enzymes with unique activities and biochemical properties. Examples of...
The marine environment presents great potential as a source of microorganisms that possess novel enzymes with unique activities and biochemical properties. Examples of such are the quorum-quenching (QQ) enzymes that hydrolyze bacterial quorum-sensing (QS) signaling molecules, such as -acyl-homoserine lactones (AHLs). QS is a form of cell-to-cell communication that enables bacteria to synchronize gene expression in correlation with population density. Searching marine metagenomes for sequences homologous to an AHL lactonase from the phosphotriesterase-like lactonase (PLL) family, we identified new putative AHL lactonases (sharing 30 to 40% amino acid identity to a thermostable PLL member). Phylogenetic analysis indicated that these putative AHL lactonases comprise a new clade of marine enzymes in the PLL family. Following recombinant expression and purification, we verified the AHL lactonase activity for one of these proteins, named moLRP (marine-originated lactonase-related protein). This enzyme presented greater activity and stability at a broad range of temperatures and pH, tolerance to high salinity levels (up to 5 M NaCl), and higher durability in bacterial culture, compared to another PLL member, parathion hydrolase (PPH). The addition of purified moLRP to cultures of Pseudomonas fluorescens inhibited its extracellular protease activity, expression of the protease encoding gene, biofilm formation, and the sedimentation process in milk-based medium. These findings suggest that moLRP is adapted to the marine environment and can potentially serve as an effective QQ enzyme, inhibiting the QS process in Gram-negative bacteria involved in food spoilage. Our results emphasize the potential of sequence and structure-based identification of new QQ enzymes from environmental metagenomes, such as from the ocean, with improved stability or activity. The findings also suggest that purified QQ enzymes can present new strategies against food spoilage, in addition to their recognized involvement in inhibiting bacterial pathogen virulence factors. Future studies on the delivery and safety of enzymatic QQ strategy against bacterial food spoilage should be performed.
Topics: Carboxylic Ester Hydrolases; Metagenome; Phylogeny; Pseudomonas; Pseudomonas fluorescens; Quorum Sensing
PubMed: 34910563
DOI: 10.1128/AEM.01680-21 -
Sensors (Basel, Switzerland) Dec 2021Organophosphates (OPs) are neurotoxic agents also used as pesticides that can permanently block the active site of the acetylcholinesterase (AChE). A robust and...
Organophosphates (OPs) are neurotoxic agents also used as pesticides that can permanently block the active site of the acetylcholinesterase (AChE). A robust and sensitive detection system of OPs utilising the enzyme mimic potential of the cysteamine capped gold nanoparticles (C-AuNPs) was developed. The detection assay was performed by stepwise addition of AChE, parathion ethyl (PE)-a candidate OP, acetylcholine chloride (ACh), C-AuNPs, and 3, 3', 5, 5'-tetramethylbenzidine (TMB) in the buffer solution. The whole sensing protocol completes in 30-40 min, including both incubations. The Transmission Electron Microscopy (TEM) results indicated that the NPs are spherical and have an average size of 13.24 nm. The monomers of C-AuNPs exhibited intense catalytic activity (nanozyme) for the oxidization of TMB, revealed by the production of instant blue colour and confirmed by a sharp peak at 652 nm. The proposed biosensor's detection limit and linear ranges were 5.8 ng·mL and 11.6-92.8 ng·mL, respectively, for PE. The results strongly advocate that the suggested facile colorimetric biosensor may provide an excellent platform for on-site monitoring of OPs.
Topics: Acetylcholinesterase; Biosensing Techniques; Colorimetry; Cysteamine; Gold; Metal Nanoparticles; Organophosphates; Pesticides
PubMed: 34884060
DOI: 10.3390/s21238050 -
Archives of Toxicology Jan 2022Organophosphorus compound pesticides (OP) are widely used in pest control and might be misused for terrorist attacks. Although acetylcholinesterase (AChE) inhibition is...
Organophosphorus pesticides exhibit compound specific effects in rat precision-cut lung slices (PCLS): mechanisms involved in airway response, cytotoxicity, inflammatory activation and antioxidative defense.
Organophosphorus compound pesticides (OP) are widely used in pest control and might be misused for terrorist attacks. Although acetylcholinesterase (AChE) inhibition is the predominant toxic mechanism, OP may induce pneumonia and formation of lung edema after poisoning and during clinical treatment as life-threatening complication. To investigate the underlying mechanisms, rat precision-cut lung slices (PCLS) were exposed to the OP parathion, malathion and their biotransformation products paraoxon and malaoxon (100-2000 µmol/L). Airway response, metabolic activity, release of LDH, cytokine expression and oxidative stress response were analyzed. A concentration-dependent inhibition of airway relaxation was observed after exposure with the oxon but not with the thion-OP. In contrast, cytotoxic effects were observed for both forms in higher concentrations. Increased cytokine expression was observed after exposure to parathion and paraoxon (IL-6, GM-CSF, MIP-1α) and IL-6 expression was dependent on NFκB activation. Intracellular GSH levels were significantly reduced by all four tested OP but an increase in GSSG and HO-1 expression was predominantly observed after malaoxon exposure. Pretreatment with the antioxidant N-acetylcysteine reduced malaoxon but not paraoxon-induced cytotoxicity. PCLS as a 3D lung model system revealed OP-induced effects depending on the particular OP. The experimental data of this study contribute to a better understanding of OP toxicity on cellular targets and may be a possible explanation for the variety of clinical outcomes induced by different OP.
Topics: Acetylcholinesterase; Animals; Antioxidants; Lung; Organophosphorus Compounds; Pesticides; Rats
PubMed: 34778934
DOI: 10.1007/s00204-021-03186-x -
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