Metabolite profiles of live or dead carp (Cyprinus carpio) exposed to endosulfan sulfate using a targeted GC–MS analysis

Endosulfan sulfate is a major oxidized metabolite of endosulfan, which is a broad-spectrum chlorinated cyclodiene insecticide. In this study, GC–MS-based metabolic profiles of dead or live carp (Cyprinus carpio) exposed to endosulfan sulfate were investigated to elucidate the molecular toxicological effects of endosulfan sulfate on carp. Three different extraction methods were compared, and a 50% methanol solution was chosen as an efficient extraction method. Carp was exposed to endosulfan sulfate at a concentration of 8 ppb for 2 days. After exposure, the whole body of the fish was homogenized with liquid N2, extracted with the 50% methanol solution and dried before TMS derivatization for GC–MS analyses of the dead and live carp. A SIM (selected ion monitoring)-library of 373 metabolites was applied after GC–MS analysis to detect 146 metabolites in carp. Based on the one-way ANOVA results (P  1.5 or < 0.667), 30 metabolites were identified as biomarkers that were significantly different in the metabolic profiles among the control, dead and live carp. A metabolic pathway analysis using MetaboAnalyst 4.0 revealed that those biomarkers were important for the living or death response to endosulfan sulfate. The pathways indicated by the metabolic pathway analysis included starch and sucrose metabolism, galactose metabolism, glycerolipid metabolism, the citrate cycle and linoleic acid metabolism. These results suggest that these pathways underwent significant perturbations over the exposure period

X-ray crystal structure of endosulfan sulfate

X-ray crystallography is an important method used to confirm the three-dimensional structure of a chemical compound. In this study, the crystal structure of endosulfan sulfate was investigated. Endosulfan sulfate is the major metabolite of the insecticide endosulfan, which is composed of two stereoisomers (α and β). From GC–MS analysis, α- and β-endosulfan each gave a single peak in the endosulfan sample, but only one peak was observed for endosulfan sulfate. Interestingly, in X-ray crystallography, two conformers of endosulfan sulfate (A and B) were observed at a ratio of 2(A):1(B). A heterocyclic seven-membered ring of conformer B assumed a horizontal-chair form, differing from two twisted forms of α-endosulfan while a vertical-chair form was observed for conformer A, showing the very similar structure to β-endosulfan; this difference in conformation is caused by differing bond angles at O(1)–C(8)–C(3) and O(2)–C(9)–C(4). In space packing, two asymmetric units were obtained, and three molecules were aligned in the order of A–A–B conformers in each unit. The total potential energy of A was slightly lower (approximately 4 kcal/mol) than B, possibly resulting in the two molecules of A that exist in a rigid crystal state. However, A and B conformers should not exist at room temperature in a solution state for GC–MS analysis, likely due to the small energy difference.The authors research was supported by contract research funds (Grant no. 550–20170104) of the Research Institute for Veterinary Science (RIVS) from the College of Veterinary Medicine and by the BK 21 Plus Program (Grant no. 5260–20150100) for Creative Veterinary Science Research. The funders had no role in study design, data collection, analysis and interpretation, decision to publish, or preparation of the manuscript

Toxicometabolomics of lindane in adult zebrafish (Danio rerio) using GC-MS/MS and LC-Orbitrap-MS/MS

Lindane is a broad-spectrum persistent organochlorine pesticide that has been used to control pests for many years. In this study, its toxic mechanisms in adult zebrafish were investigated using targeted metabolomics with GC-MS/MS and non-targeted metabolomics with LC-Orbitrap-MS/MS. Zebrafish was exposed to lindane in water for 48 h in three groups: control, low exposure (1/10 LC50) and high exposure (LC50). In the zebrafish exposed to low concentration of lindane, 2.24–3.98 mg/kg of lindane were determined, while 35.67–56.46 mg/kg were observed in the zebrafish exposed to high concentration. A total of 118 metabolites were identified from 394 metabolites on GC-MS/MS and 45 metabolites were selected as biomarkers. A total of 62 metabolites were identified on LC-Orbitrap-MS/MS and 7 metabolites were selected as biomarkers. Three groups were well separated on partial least squares-discriminant analysis (PLS-DA), and a total of 52 metabolites in both the targeted and non-targeted metabolites were selected as biomarkers through VIP and ANOVA tests to construct a heatmap. Five metabolic pathways such as the pentose phosphate pathway (PPP), histidine metabolism, phenylalanine metabolism, alanine/aspartate/glutamate metabolism, and phenylalanine/tyrosine/tryptophan biosynthesis, were observed to show toxicologically significant alterations. Oxidative stress was also confirmed through MDA and ROS assays. Such perturbations of the metabolic pathways of zebrafish caused by the exposure to lindane resulted in significant toxicological effects

Translocation of residual ethoprophos and tricyclazole from soil to spinach

The dissipation of ethoprophos and tricyclazole in soil and their translocation tendency to spinach were investigated. Prior to field trials, the analytical method for the determination of these pesticide residues was optimized and validated on soil and spinach. The field trial was conducted under greenhouse conditions for two different pretreatment periods with the pesticides. After treating with pesticides 30 (PBI-30) and 60 days (PBI-60) before seeding, soil samples were collected on different days for the dissipation study of soil. Spinach samples were harvested from the soil, and 50% and 100% mature spinach samples were collected. The initial amounts of ethoprophos residue in the PBI-60 and PBI-30 soils were 0.21 and 2.74 mg/kg, respectively, and these both decreased to less than 0.01 mg/kg on the day of spinach harvest. Similar initial residues of tricyclazole were observed in the PBI-60 (0.87 mg/kg) and PBI-30 soils (0.84 mg/kg), and these decreased to 0.44 and 0.34 mg/kg, respectively. The half-lives of ethoprophos in the soils were calculated as 7.6 and 4.8 days, respectively, while relatively long half-lives of 36.5 and 77.0 days were calculated for tricyclazole. According to the pesticide residue amounts in the spinach, the translocation rate from the soil to the spinach was determined. In the case of ethoprophos, the residual amount was already rapidly degraded in the soil, and the translocation rate could not be confirmed. On the other hand, for tricyclazole, it was confirmed that 1.19 to 1.61% of the residual amount in soil was transferred to spinach. According to these results, safe management guidelines for tricyclazole in soil were suggested considering the maximum residue limit on spinach.This work was supported by the Rural Development Administration (PJ0152772020)

A Quantitative Tandem Mass Spectrometry and Scaled-Down QuEChERS Approach for Simultaneous Analysis of Pesticide Multiresidues in Human Urine

Multiresidual pesticide determination in a biological sample is essential for an immediate decision and response related to various pesticide intoxications. A rapid and simultaneous analytical method for 260 pesticides in human urine was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). High speed positive/negative switching electrospray ionization (ESI) mode was used, and scheduled multiple reaction monitoring (MRM) was optimized. Three versions of scaled-down QuEChERS procedures were evaluated, and the procedure using non-buffer reagents (magnesium sulfate and sodium chloride) and excluding cleanup steps was selected for optimum pesticide extraction. The limit of quantitation (LOQ) in this methodology was 10 ng/mL for each target pesticide, and correlation coefficient (r2) values of calibration curves were &#8805;0.988 (linearity range; 10&#8211;250 ng/mL). In accuracy and precision tests, the relative error ranges were &#8722;18.4% to 19.5%, with relative standard deviation (RSD) 2.1%&#8211;19.9% at an LOQ level (10 ng/mL), and &#8722;14.7% to 14.9% (RSD; 0.6%&#8211;14.9%) at higher concentrations (50, 150, and 250 ng/mL). Recovery range was 54.2%&#8211;113.9% (RSD; 0.3%&#8211;20.0%), and the soft matrix effect (range; &#8722;20% to 20%) was observed in 75.4% of target pesticides. The established bioanalytical methods are sufficient for application to biomonitoring in agricultural exposures and applicable in the forensic and clinic

Occupational exposure and risk assessment for agricultural workers of thiamethoxam in vineyards

© 2022 The AuthorsDermal &amp; inhalation exposure was examined and according to these results, risk assessment of agricultural workers to thiamethoxam was performed during pesticide mixing/loading and hand-held sprayer application (11 replicates, each of about 1000 L of spray suspension) in vineyards. For the whole body dosimetry (WBD), clothing (Outer and inner), gauze, and nitrile gloves were analyzed to determine dermal exposure using whole-body dosimetry exposure protocol. The inhalation exposure was measured using a glass fiber filter with an IOM sampler. Analytical method validation of exposure matrices was evaluated including the field recovery and breakthrough test. The dermal exposure amount during mixing/loading was 0.163 mg (0.0004% of the total mixed/loaded active ingredient [a.i.]), whereas there was no inhalation exposure. The gloves (0.154 mg, 94.5%) were the most exposed body parts followed by the chest and stomach (0.009 mg, 5.5%). During application, the dermal and inhalation exposure amounts were 32.3 mg (0.07% of the total applied a.i.) and 10.8 µg (2.4 × 10−6% of the total applied a.i), respectively. The shin (35.1%) had the highest exposure to pesticides, followed by the chest &amp; stomach (15.6%) and pelvis (12.6%). In case of mixing/loading, the amounts of actual dermal exposure (ADE) and actual inhalation exposure (AIE) were 0.0 and 0.0 μg/day, while those of ADE and AIE were 4707.6 and 15.8 μg/day for application. In risk assessment of the two different scenarios, the risk index was much lower than 1 (mixing/loading:0.000, application:0.014), indicating that vineyard workers are at low risk of thiamethoxam exposure. To determine the validity of the risk assessment using WBD method, the urinary metabolite was analyzed. Comparison of biomonitoring data and WBD exposure data show a reliable correlation (r = 0.885, p = 0.0003), suggesting that these are suitable methods to estimate exposure.N

Modified Aloe Polysaccharide Restores Chronic Stress-Induced Immunosuppression in Mice

Chronic stress generally experienced in our daily lives; is known to augment disease vulnerability by suppressing the host immune system. In the present study; the effect of modified Aloe polysaccharide (MAP) on chronic stress-induced immunosuppression was studied; this Aloe compound was characterized in our earlier study. Mice were orally administered with MAP for 24 days and exposed to electric foot shock (EFS; duration; 3 min; interval; 10 s; intensity; 2 mA) for 17 days. The stress-related immunosuppression and restorative effect of MAP were then analyzed by measuring various immunological parameters. MAP treatment alleviated lymphoid atrophy and body weight loss. The numbers of lymphocyte subsets were significantly normalized in MAP-treated mice. Oral administration of MAP also restored the proliferative activities of lymphocytes; ovalbumin (OVA)-specific T cell proliferation; antibody production; and the cell killing activity of cytotoxic T lymphocytes. In summary; oral administration of MAP ameliorated chronic EFS stress-induced immunosuppression

Robotic Completion Thyroidectomy via the Bilateral Axillo-Breast Approach

Background: Bilateral axillo-breast approach (BABA) robotic thyroidectomy has been successfully performed for thyroid cancer patients with excellent cosmetic results. Completion thyroidectomy is sometimes necessary after thyroid lobectomy, and whether it has a higher complication rate than the primary operation due to the presence of adhesions remains controversial. The aim of this study was to evaluate surgical outcomes, including operation time and postoperative complications, in patients who underwent BABA robotic completion thyroidectomy. Methods: From Jan 2012 to Aug 2020, 33 consecutive patients underwent BABA robotic completion thyroidectomy for a thyroid malignancy after BABA robotic thyroid lobectomy. The procedures were divided into five steps: (1) robot setting and surgical draping, (2) flap dissection, (3) robot docking, (4) thyroidectomy, and (5) closure. Clinicopathological characteristics, operation time, and postoperative complications were reviewed. Results: The total operation time was shorter for completion thyroidectomy than for the initial operation (164.8 ± 31.7 min vs. 179.8 ± 27.1 min, p = 0.043). Among the robotic thyroidectomy steps, the duration of the thyroidectomy step was shorter than that of the initial operation (69.6 ± 20.9 min vs. 83.0 ± 19.5 min, p = 0.009. One patient (1/33, 3.0%) needed hematoma evacuation under the flap area immediately after surgery. Three patients (3/33, 9.1%) showed transient hypoparathyroidism, and one patient (1/33, 3.0%) had permanent hypoparathyroidism. Two patients (2/33, 6.1%) showed transient vocal cord palsy and recovered within 3 months following the completion thyroidectomy. There were no cases of open conversion, tracheal injury, flap injury or wound infection. Conclusions: BABA robotic completion thyroidectomy could be performed safely without completion-related complication