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Existing methods for the analysis of pesticides in human breast milk involve multiple extraction steps requiring large sample and solvent volumes, which can be a major obstacle in large epidemiologic studies. Here, we developed a simple, low-volume method for extracting organophosphates, pyrethroids, carbamates, atrazine, and imidacloprid from 100 to 200 μL of human breast milk. Oxiglutatione Multiple extraction protocols were tested including microwave-assisted acid/base digestion and double-solvent extraction with 2 or 20 mL of 21 (v/v) dichloromethane/hexane, with or without subsequent solid-phase extraction (SPE) cleanup. Samples were analyzed by liquid chromatography tandem mass spectrometry. Analyte recoveries and reproducibility were highest when 100-200 μL of milk were extracted with 2 mL of dichloromethane/hexane without subsequent SPE steps. Analysis of 79 breast milk samples using this method revealed the presence of carbamates, organophosphates, pyrethroids, and imidacloprid at detection frequencies of 79-96, 53-90, 1-7, and 61%, respectively. This study demonstrates the feasibility of a simple low-volume extraction method for measuring pesticides in human breast milk.The evaporation of P from liquid Si under vacuum and reduced pressures of H2, He, and Ar was studied to evaluate the feasibility of effective P removal with insignificant Si loss. It was found that the introduction of Ar and He inert gases at low pressures reduces the rate of P removal, and their pressure decrease will increase the process rate. Moreover, the kinetics of P removal was higher in He than in Ar, with simultaneous lower Si loss. Under reduced pressures of H2 gas, however, the P removal rate was higher than that under vacuum conditions with the lowest Si loss. Quantum chemistry and dynamics simulations were applied, and the results indicated that P can maintain its momentum for longer distances in H2 once it is evaporated from the melt surface and then can travel far away from the surface, while Si atoms lose their momentum in closer distances, yielding less net Si flux to the gas phase. Moreover, this distance is significantly increased with decreasing pressure for H2, He, and Ar gases; however, it is the largest for H2 and the lowest for Ar for a given pressure, while the temperature effect is insignificant. The rate of P evaporation was accelerated by applying an additional vacuum tube close to the melt surface for taking out the hot gas particles before they lose their temperature and velocity. It was shown that this technique contributes to the rate of process by preventing condensing gas stream back to the melt surface.A highly efficient approach to a new class of polycyclic 8-azapurines, benzo[4,5]imidazo[1,2-a][1,2,3]triazolo[4,5-e]pyrimidines (BITPs), with good photophysical characteristics is proposed. The approach comprises condensation of aminobenzimidazoles with 3-oxo-2-phenylazopropionitrile to form 3-(arylazo)benzo[4,5]imidazo[1,2-a]pyrimidine-4-amines, which undergo oxidative cyclization by the catalytic action of copper(II) acetate, resulting in BITPs with 73-84% yield. Spectral investigations demonstrated the fluorescent properties of BITPs, exhibiting good quantum yields (up to 60%) with maxima absorption at 379-399 and emission at 471-505 nm.The synthesis of an octa-armed 24-membered cyclic octaamine (1) is reported. When 4-benzyl-1,4,7,10-tetraazacyclododecane-2,6-dione (3a) was prepared by the reaction of diethylenetriamine with diethyl N-benzyliminodiacetate (2), a dimeric macrocycle (3b) was obtained as a byproduct in a 5% yield. An octa-armed 24-membered cyclic octaamine (1), named Cosmosen, was prepared via the reductive amination and reduction of 3b. The binding constants for the 11 and 21 (Ag+/1) complexation of 1 were estimated to be ca. 7.9 and 13.9, respectively, by titration experiments using UV-vis spectrometry in methanol and chloroform (v/v, 91) solutions at 298 K.

Although second-look endoscopy (SLE) is frequently performed after gastric endoscopic submucosal dissection (ESD) to prevent bleeding, no studies have reported SLE findings after colorectal ESD. This study aimed to investigate SLE findings and their role in preventing delayed bleeding after colorectal ESD.

Post-ESD ulcer appearances were divided into coagulation (with or without remnant minor vessels) and clip closure groups. SLE findings were categorized according to the Forrest classification (high-risk ulcer stigma [type I and IIa] and low-risk ulcer stigma [type IIb, IIc, III, or clip closure]), and risk factors for high-risk ulcer stigma were analyzed.

Among the 375 cases investigated, SLEs were performed in 171 (45.6%) patients. The incidences of high-risk ulcer stigma and low-risk stigma were 5.3% (9/171) and 94.7% (162/171), respectively. During SLE, endoscopic hemostasis was performed more frequently in the high-risk ulcer stigma group than in the lowrisk ulcer stigma group (44.4% [4/9] vs. 1.9% [3/162], respectively; p < 0.001), but most of the endoscopic hemostasis in the high-risk ulcer stigma group (3/4, 75.0%) were prophylactic hemostasis. Post-ESD delayed bleeding occurred in three (0.8%) patients belonging to the SLE group, of which, one patient was from the high-risk stigma group and two were from the low-risk stigma group.

The incidence of high-risk ulcer stigma during SLE was low, and delayed bleeding occurred in, both, high-risk and low-risk groups of SLE. SLEs performed after colorectal ESD may not be effective in preventing delayed bleeding, and further prospective studies are needed to evaluate the efficacy of SLE in post-colorectal ESD.

The incidence of high-risk ulcer stigma during SLE was low, and delayed bleeding occurred in, both, high-risk and low-risk groups of SLE. SLEs performed after colorectal ESD may not be effective in preventing delayed bleeding, and further prospective studies are needed to evaluate the efficacy of SLE in post-colorectal ESD.The clinical phenotypes of nonalcoholic fatty liver disease (NAFLD) encompass from simple steatosis to nonalcoholic steatohepatitis (NASH) with varying degrees of fibrosis or cirrhosis. Liver biopsy has been the standard to diagnose NASH. However, there has been strong need for precise and accurate noninvasive tests because of invasiveness and sampling variability of biopsy. Metabolomics has drawn attention as a promising diagnostic methodology in the field of NAFLD, particularly to unravel metabolic alterations which plays relevant roles in the progression of NASH. There have been numerous metabolomics researches to find new biomarker of NASH in the last decade, fueled by the recent advances in the metabolomics methodology. This review briefly covers recent research advances on the lipidomics, amino acids and bile acid metabolomics regarding continuing attempts to discover relevant biomarkers for NASH.