Target and Semitarget Analysis of Advanced Glycation End Products Using a New Pair of Permanently Positively Charged Stable Isotope Labeling Agents.

A pair of positively charged stable isotope labeling (SIL) agents, (4-carbonochloridoylphenyl)-trimethylazanium iodide (-CCPTA) and -CCPTA, were designed and synthesized. These agents were employed in the precolumn labeling of advanced glycation end products (AGEs) within 5 min under mild conditions. Through derivatization, the mass spectrometry response of the AGEs was enhanced by approximately 2 orders of magnitude.

Pyridinium and ammonium stable isotope labeling agents and their performance in the analysis of alkylamines in food and food packaging materials.

Two pairs of stable isotope labeling (SIL) agents, (4-carboxyphenyl)trimethylammonium iodide (d-CPTA) and its deuterated counterpart d-CPTA, 1-methyl-nicotinamide iodide (d-MNA) and its deuterated counterpart d-MNA, were designed and synthesized. Their mass spectrometry (MS) sensitivity enhancement effect was studied and compared with commercial dansyl chloride to provide inspiration for labeling agent design. CPTA with quaternary ammonium group showed much higher MS sensitivity enhancement effect and was applied to the SIL analysis of alkylamines in food and food packaging materials.

Isolation and identification of hemostatic steroidal glycosides from Ypsilandra thibetica.

The phytoconstituents of the fraction with hemostatic activity of the 70% aqueous ethanol extract of Ypsilandra thibetica Franch. were investigated. As a result, fourteen previously unreported spirostanol saponins, ypsilandrosides Z1-Z14, and nine known analogues were isolated and characterized by MS, NMR, and chemical methods.

Blocking Rice Shoot Gravitropism by Altering One Amino Acid in LAZY1.

Tiller angle is an important trait that determines plant architecture and yield in cereal crops. Tiller angle is partially controlled during gravistimulation by the dynamic re-allocation of LAZY1 (LA1) protein between the nucleus and plasma membrane, but the underlying mechanism remains unclear. In this study, we identified and characterized a new allele of based on analysis of a rice ( L.

Ypsilandrosides U-Y, five new steroidal saponins from Ypsilandra thibetica.

Phytochemical reinvestigation on the whole plants of Ypsilandra thibetica obtained four new spirostanol glycosides, named ypsilandrosides U-X (1-4), and one new cholestanol glycoside, named ypsilandroside Y (5). Their structures have been established by extensive spectroscopic data and chemical methods. Among them, compound 4 is a rare spirostanol glycoside which possesses a novel 5(6 → 7) abeo-steroidal aglycone, while compound 1 is a first spirostanol bisdesmoside attached to C-3 and C-12, respectively, isolated from the genus Ypsilandra.

All-in-one: a robust fluorescent fusion protein vector toolbox for protein localization and BiFC analyses in plants.

Fluorescent tagging protein localization (FTPL) and bimolecular fluorescence complementation (BiFC) are popular tools for in vivo analyses of the subcellular localizations of proteins and protein-protein interactions in plant cells. The efficiency of fluorescent fusion protein (FFP) expression analyses is typically impaired when the FFP genes are co-transformed on separate plasmids compared to when all are cloned and transformed in a single vector. Functional genomics applications using FFPs such as a gene family studies also often require the generation of multiple plasmids.

MiR-940 Serves as a Diagnostic Biomarker in Patients with Sepsis and Regulates Sepsis-Induced Inflammation and Myocardial Dysfunction.

Introduction: Sepsis is a heterogeneous syndrome with a life-long threat caused by infection. This study aimed to investigate the clinical function of miR-940 and its influence on cardiomyocyte models.

Methods: The relative expression of miR-940 was assessed by qRT-PCR and the roles in the clinical diagnosis of miR-940 were revealed by the ROC curve.

LncRNA RMST Regulates Neuronal Apoptosis and Inflammatory Response via Sponging miR-150-5p in Parkinson's Disease.

Introduction: LncRNA rhabdomyosarcoma 2-associated transcript (RMST) serves as a key regulator in neural stem cell fate and is involved in the progression of different neurological diseases. In this research, the serum level and clinical value of RMST in Parkinson's disease (PD) patients were detected, and the underlying mechanism was explored.

Methods: Ninety-nine PD patients and 93 healthy individuals were collected for clinical experiments.

A novel fluorescent labeling reagent, 2-(9-acridone)-ethyl chloroformate, and its application to the analysis of free amino acids in honey samples by HPLC with fluorescence detection and identification with online ESI-MS.

In this study, a novel fluorescent labeling reagent 2-(9-acridone)-ethyl chloroformate (AEC-Cl) was designed, synthesized and applied for the determination of free amino acids by high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The free amino acids were rapidly and efficiently labeled by AEC-Cl in the presence of basic catalyst (pH 9.0) within 5 min at room temperature (25 °C).

Permanently Positively Charged Stable Isotope Labeling Agents and Its Application in the Accurate Quantitation of Alkylphenols Migrated from Plastics to Edible Oils.

A new permanently positively charged stable isotope labeling (SIL) agent pair, 4-(((2,5-dioxopyrrolidin-1-yl)oxy)carbonyl)-,,-trimethylbenzenaminium iodide(DPTBA) and its deuterated counterpart -DPTBA, was designed and synthesized. The SIL agents were applied to the liquid chromatography-tandem mass spectrometry analysis of alkylphenols. Light labeled standards and heavy labeled samples were mixed and analyzed simultaneously.

Cationic Surfactant Modified 3D COF and Its Application in the Adsorption of UV Filters and Alkylphenols from Food Packaging Material Migrants.

Hexadecyl trimethylammonium bromide (CTAB) micelles were applied in the synthesis of covalent organic frameworks (COFs) for the first time to achieve the synthesis of 3D COF from 2D materials. Benzidine, one raw material for COF, was enclosed in the CTAB micelles because of the hydrophobic effect, and thus the target COF, which can be formed immediately with the aid of p-toluenesulfonic acid, grew in a micelle guided 3D form. The synthesized 3D COF showed a flower-like structure, whereas the COF synthesized without CTAB showed a smooth structure.

Determination of residual organophosphorus thioester pesticides in agricultural products by chemical isotope-labelling liquid chromatography-tandem mass spectrometry coupled with in-syringe dispersive solid phase clean-up and in situ cleavage.

Chemical isotope labelling in combination with high-performance liquid chromatography-tandem mass spectrometry (CIL-HPLC-MS/MS) is a powerful method for quantitative profiling of targeted molecules. In the current work, we successfully developed a novel CIL-HPLC-MS/MS method for quantitative profiling of residual organophosphorus thioester pesticides (OPTPs) in agricultural products through the determination of the cleavage products of thiol (CP-thiol) compounds. In this method, we synthesized a novel pair of CIL reagents, i.

The OsmiR396-OsGRF8-OsF3H-flavonoid pathway mediates resistance to the brown planthopper in rice (Oryza sativa).

Multi-functional microRNAs (miRNAs) are emerging as key modulators of plant-pathogen interactions. Although the involvement of some miRNAs in plant-insect interactions has been revealed, the underlying mechanisms are still elusive. The brown planthopper (BPH) is the most notorious rice (Oryza sativa)-specific insect that causes severe yield losses each year and requires urgent biological control.

Cationic gemini surfactant-resorcinol-aldehyde resin and its application in the extraction of endocrine disrupting compounds from food contacting materials.

A new cationic gemini surfactant-resorcinol/formaldehyde resin was designed and synthesized. Cationic gemini surfactant was introduced into the resorcinol/formaldehyde resin for the first time and led to the retention of negatively charged endocrine disrupting compounds (EDCs) through electrostatic interactions, hydrogen bonding and π-π interactions. The synthesized material showed good performance in the dispersive micro-solid phase extraction (D-μ-SPE) of EDCs such as alkylphenol and phenoxy acid herbicides from food packaging migrants.

Analysis of Fatty Acids in Trichosanthes kirilowii Maxim by MSPD and Fluorescence Derivatization.

The extraction and analysis of free fatty acids (FFAs) in the whole natural plants are reported. The aminopropyl-functionalized SBA-15 was designed to increase the efficiency of the matrix solid-phase dispersion (MSPD) extraction method. MSPD extraction was performed using to extract FFAs via acid-base interactions.

Quaternary ammonium-functionalized MCM-48 mesoporous silica as a sorbent for the dispersive solid-phase extraction of endocrine disrupting compounds in water.

MCM-48 mesoporous silica was functionalized with dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, a quaternary ammonium salt with a long hydrophobic chain, to prepare a new sorbent for the dispersive solid-phase extraction (DSPE) of seven endocrine disrupting compounds (EDCs) including 4-hexylphenol, 4-octylphenol, 4-nonylphenol, bisphenol A, estrone, 17β-estradiol and estriol in water. A series of differently functionalized MCM-48 materials were also synthesized, and they served as reference materials to study the mechanism. The developed DSPE method was combined with HPLC with fluorescence detection to evaluate the adsorption performance.

3-(2-Bromoacetamido)-N-(9-ethyl-9H)-carbazol fluorescent probe and its application for the determination of thiophenols in rubber products by HPLC with fluorescence detection and atmospheric chemical ionization mass spectrometry identification.

A rapid, sensitive, and selective precolumn derivatization method for the simultaneous determination of eight thiophenols using 3-(2-bromoacetamido)-N-(9-ethyl-9H)-carbazol as a labeling reagent by high-performance liquid chromatography with fluorescence detection has been developed. The labeling reagent reacted with thiophenols at 50°C for 50 min in aqueous acetonitrile in the presence of borate buffer (0.10 mol/L, pH 11.

A rapid, accurate and sensitive method with the new stable isotopic tags based on microwave-assisted dispersive liquid-liquid microextraction and its application to the determination of hydroxyl UV filters in environmental water samples.

A rapid, accurate and sensitive method, using the stable isotope labeling (SIL), microwave-assisted dispersive liquid-liquid micro extraction (MADLLME) and the ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), was developed and validated for the determination of hydroxyl UV Filters in environmental water samples. A pair of new isotopic tags D-/D-1-methylindole-3-acetic acid (D-/D-MIAA) is synthesized, with which a simple yet efficient pretreatment MADLLME-SIL is developed. Under the optimized conditions (80℃, 240W, 180s), the sample pretreatment including analyte extraction, pre-concentration and isotope labeling can be finished conveniently in only 9min.

Stable isotope labeling assisted liquid chromatography-tandem mass spectrometry for the analysis of perfluorinated carboxylic acids in serum samples.

A new stable isotope labeling (SIL) reagent pair, 10-methyl-acridone-2-sulfonohydrazide (MASH) and its deuterated counterpart d-MASH was synthesized and successfully applied to the analysis of perfluorinated carboxylic acids (PFCAs) in serum samples. The limits of detection (LODs) were in the range of 0.07-0.

Gas Purge Microextraction Coupled with Stable Isotope Labeling-Liquid Chromatography/Mass Spectrometry for the Analysis of Bromophenols in Aquatic Products.

A green, sensitive, and accurate method was developed for the extraction and determination of bromophenols (BPs) from aquatic products by using organic solvent-free gas purge microsyringe extraction (GP-MSE) technique in combination with stable isotope labeling (SIL) strategy. BPs were extracted by NaHCO buffer solution, with recoveries varying from 92.0% to 98.

Dual ultrasonic-assisted dispersive liquid-liquid microextraction coupled with microwave-assisted derivatization for simultaneous determination of 20(S)-protopanaxadiol and 20(S)-protopanaxatriol by ultra high performance liquid chromatography-tandem mass spectrometry.

This paper, for the first time, reported a speedy hyphenated technique of low toxic dual ultrasonic-assisted dispersive liquid-liquid microextraction (dual-UADLLME) coupled with microwave-assisted derivatization (MAD) for the simultaneous determination of 20(S)-protopanaxadiol (PPD) and 20(S)-protopanaxatriol (PPT). The developed method was based on ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection using multiple-reaction monitoring (MRM) mode. A mass spectrometry sensitizing reagent, 4'-carboxy-substituted rosamine (CSR) with high reaction activity and ionization efficiency was synthesized and firstly used as derivatization reagent.

Accurate Determination of Amino Acids in Serum Samples by Liquid Chromatography-Tandem Mass Spectrometry Using a Stable Isotope Labeling Strategy.

An accurate and sensitive liquid chromatography-tandem mass spectrometry method was developed for the analysis of amino acids (isoleucine, leucine, valine, tyrosine, phenylalanine and tryptophan) in serum samples using a stable isotope labeling strategy. Amino acid samples and standards were, respectively, derivatized by 10-methyl-acridone-2-sulfonyl chloride (d0-MASC) and its deuterated counterpart d3-MASC to form isotopic pairs which co-eluted and were detected by an MS detector at the same time. Accurate internal standard-based quantification was thereby achieved without the use of any internal standard analogy.

Development of ultrasonic-assisted closed in-syringe extraction and derivatization for the determination of labile abietic acid and dehydroabietic acid in cosmetics.

Two resin acids, abietic acid (AA) and dehydroabietic acid (DHAA), in cosmetics may cause allergy or toxicoderma, but remain inaccurately investigated due to their lability. In this work, an accurate, sensitive, efficient and convenient method, utilizing the ultrasonic-assisted closed in-syringe extraction and derivatization (UCSED) prior to high performance liquid chromatography (HPLC) coupled with fluorescence detection (FLD) and on-line tandem mass spectra (MS/MS), has been developed. Analytes are extracted by acetonitrile (10/1, v/m) in a sealed syringe under safe condition (60°C; 15 min; nitrogen atmosphere) and then in-syringe derivatized by 2-(2-(anthracen-10-yl)-1H-naphtho[2,3-d]imidazol-1-yl) ethyl-p-toluenesulfonate (ANITS) (8-fold, 93°C, 30 min, DMF as co-solvent, K2CO3 as catalyst).

Sensitive, accurate and rapid detection of trace aliphatic amines in environmental samples with ultrasonic-assisted derivatization microextraction using a new fluorescent reagent for high performance liquid chromatography.

A new fluorescent reagent, 1-(1H-imidazol-1-yl)-2-(2-phenyl-1H-phenanthro[9,10-d]imidazol-1-yl)ethanone (IPPIE), is synthesized, and a simple pretreatment based on ultrasonic-assisted derivatization microextraction (UDME) with IPPIE is proposed for the selective derivatization of 12 aliphatic amines (C1: methylamine-C12: dodecylamine) in complex matrix samples (irrigation water, river water, waste water, cultivated soil, riverbank soil and riverbed soil). Under the optimal experimental conditions (solvent: ACN-HCl, catalyst: none, molar ratio: 4.3, time: 8 min and temperature: 80°C), micro amount of sample (40 μL; 5mg) can be pretreated in only 10 min, with no preconcentration, evaporation or other additional manual operations required.

Determination of triterpenic acids in fruits by a novel high performance liquid chromatography method with high sensitivity and specificity.

A novel and interesting pre-column derivatisation method was developed for the analysis of triterpenic acids by high-performance liquid chromatography (HPLC) with fluorescence detection. Each triterpenic acid produced two HPLC peaks with similar peak areas after derivatising with chiral 1-(9H-carbazol-9-yl) propan-2-yl-methanesulfonate (CPMS), while the fatty acid derivative of CPMS had only one peak. This phenomenon greatly increased the confidence in analyte confirmation.