Superlong Metal-Organic Framework Micro-/Nanofibers for Selective Vitamin Absorption.

Superlong MOF-74-type micro/nanofibers, which have aspect ratios much higher than 200, are synthesized via nanoparticulate MOF-mediated recrystallization. Co-MOF-74 microfibers have high crystallinity, whereas Co-MOF-74-II nanofibers are composed of nanocrystals and amorphous phases, even though they have nanofibrous morphology. Both MOFs consist of plenty of micropores with diameters in the range of 1.

A novel automated multi-cycle magnetic solid-phase extraction coupled to LC-MS/MS to study the disorders of six functional B vitamins in patients with gastroenterology and hyperhomocysteinemia.

B vitamins are essential for human life and their disorders can cause a variety of diseases. Solid-phase extraction (SPE) coupled to LC-MS/MS is a preferred technique for determining multiple B vitamins, however, their complexity in real biological matrices makes it hard to achieve satisfactory recovery and accuracy when simultaneous detection. In this study, a novel automated multi-cycle magnetic SPE (MSPE) coupled to the LC-MS/MS method was established using a mixed-mode anion exchange magnetic adsorbent for the simultaneous extraction of six functional B vitamins, including methylmalonic acid, riboflavin, pantothenic acid, 4-pyridoxic acid, folic acid, and 5-methyltetrahydrofolate.

Simple and fast determination of tetrodotoxin in human plasma based on hydrophilic-interaction/ion-exchange mixed-mode solid phase extraction combined with liquid chromatography-tandem mass spectroscopy.

In this study, we developed and validated a simple, fast and sensitive LC-MS/MS method for the measurement of tetrodotoxin (TTX) in human plasma. Three HILIC-type solid phase extraction (SPE) carriers (PSA, silica, Siphila i HILIX) with different stationary phase functional groups were compared. The Siphila i HILIX SPE plate containing multi-carboxyl groups was finally selected due to obviously better extraction recovery of TTX (about 80% of recovery from plasma samples) than the other two and no significant matrix effects were observed, which was speculated to have mixed-mode synergistic effects of hydrophilic interaction and ion exchange.

Comparison of four different immunoassays and a rapid isotope-dilution liquid chromatography-tandem mass spectrometry assay for serum folate.

Objectives: Accurate measurement of serum folate is essential for the diagnosis and management of various disorders. This study aims to investigate the between-method differences of four immunoassays and a rapid isotope-dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) method.

Methods: Roche Cobas (USA), Abbott Alinity i2000 (USA), Beckman Coulter Access (USA), Mindray CL-6000i (China), and the ID-LC-MS/MS method were compared using 46 human serum samples.

Fasting serum fructose is associated with risk of gestational diabetes mellitus.

Objective: To investigate the association of fasting serum fructose concentrations and the incidence of GDM.

Research Design And Methods: Five hundred twenty six pregnant women who attended the obstetric clinic of Xinhua Hospital, Chongming Branch were recruited prospectively from September 2019 to November 2020. Fasting serum fructose concentrations were measured by a validated liquid chromatography-tandem mass spectrometry method.

Euphornin L promotes lipid clearance by dual regulation of LDLR and PCSK9.

Our previous study identified euphornin L as an active lipid-lowering compound in high-fat diet-fed Golden Syrian hamsters. The aim of the present study was to investigate the mechanisms underlying the lipid-lowering effects of euphornin L. Euphornin L in HepG2 cells was assessed via DiI-LDL update assays and found to increase LDL-update and LDLR protein levels.

Identification of circulating sphingosine kinase-related metabolites for prediction of type 2 diabetes.

Background: Sphingosine Kinase (SphK) that catalyzes sphingosine (Sph) to sphingosine 1-phosphate (S1P), plays a key role in both sphingolipid metabolism and cellular signaling. While SphK has been implicated in type 2 diabetes mellitus (T2DM), it is unexplored in humans. Herein, we investigated whether circulating SphK-related metabolites are associated with T2DM incidence in an established prospective cohort.

Direct analysis in real time-mass spectrometry for rapid quantification of five anti-arrhythmic drugs in human serum: application to therapeutic drug monitoring.

Therapeutic drug monitoring (TDM) is necessary for the optimal administration of anti-arrhythmic drugs in the treatment of heart arrhythmia. The present study aimed to develop and validate a direct analysis in real time tandem mass spectrometry (DART-MS/MS) method for the rapid and simultaneous determination of five anti-arrhythmic drugs (metoprolol, diltiazem, amiodarone, propafenone, and verapamil) and one metabolite (5-hydroxy(OH)-propafenone) in human serum. After the addition of isotope-labeled internal standards and protein precipitation with acetonitrile, anti-arrhythmic drugs were ionized by DART in positive mode followed by multiple reaction monitoring (MRM) detection.

Fasting Serum Fructose Levels Are Associated With Risk of Incident Type 2 Diabetes in Middle-Aged and Older Chinese Population.

Objective: We investigated the relationship between fasting serum fructose levels and the risk of incident type 2 diabetes in a prospective Chinese cohort.

Research Design And Methods: Among 949 community-based participants aged ≥40 years without diabetes at baseline, fasting serum fructose levels were measured using liquid chromatography-tandem mass spectrometry. The participants were followed up for the occurrence of diabetes.

23,24-Dihydrocucurbitacin B promotes lipid clearance by dual transcriptional regulation of LDLR and PCSK9.

23,24-Dihydrocucurbitacin B (designated as C95 in this article) is a cucurbitane triterpenoid that has been shown to possess a variety of pharmacological activities, such as anti-inflammatory and anti-HIV-1 activities etc. In this study, we investigated the effects of 23,24-dihydrocucurbitacin B on lipid regulation. We showed that 23,24-dihydrocucurbitacin B (1-5 μM) dose-dependently promoted DiI-LDL uptake in HepG2 cells by upregulating low-density lipoprotein receptor (LDLR) protein.

Application of a micro plasma collection card for the detection of homocysteine by liquid chromatography with tandem mass spectrometry.

Generally, it is recommended that blood samples for homocysteine detection should be centrifuged immediately to separate plasma in order to avoid continuous synthesis by blood cells. The use of a micro plasma collection card may improve sample stability and result accuracy by offering automatic and instant plasma separation. We compare a micro plasma collection method with routine wet plasma to explore applications of the dried plasma spots for homocysteine determination by using liquid chromatography with tandem mass spectrometry.

Oral Bioavailability and Mass Balance Studies of a Novel Anti-arrhythmic Agent Sulcardine Sulfate in Sprague-Dawley Rats and Beagle Dogs.

Background And Objectives: Sulcardine sulfate is a newly developed candidate drug used to control arrhythmias. The aim of this research was to investigate the pharmacokinetics, bioavailability and excretion characteristics of sulcardine in animals.

Methods: Sprague-Dawley rats were orally and intravenously given sulcardine at 20 and 40 mg/kg.

Determination of the novel antiarrhythmic drug sulcardine sulfate in human plasma by liquid chromatography tandem mass spectrometry and its application in a clinical pharmacokinetic study.

Sulcardine sulfate (Sul), a novel antiarrhythmic agent, is currently in phase I and phase II clinical trials. To elucidate its clinical pharmacokinetic characteristics, a rapid and accurate liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the quantification of Sul in human plasma. Plasma samples were precipitated by acetonitrile and isotope-labeled sulcardine was added as internal standard.

Pharmacokinetics of trantinterol and its metabolite in healthy elderly and young subjects.

Objective: The aim of this study was to investigate and compare the pharmacokinetics of trantinterol and its active amphoteric carboxylic acid metabolite (1-carbonyl trantinterol) between the healthy elderly and young subjects.

Methods: This was a single-center, open-label, parallel-group study completed by 22 healthy subjects (≥65 years (the elderly group); 18-45 years (the young group); 9 males and 2 females per age group) receiving single oral dose of 50 μg trantinterol tablets. Blood samples were taken at intervals up to 48 hours post-dose.

Simultaneous Determination of Trantinterol and One of Its Major Metabolites, 1-Carbonyl Trantinterol, in Human Plasma by LC-MS-MS.

A highly selective and sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of trantinterol and one of its major metabolites, 1-carbonyl trantinterol, in human plasma. An Oasis MCX 96-well solid-phase extraction cartridge and a SeQuantTM ZIC(®)-HILIC LC column were used for sample preparation and chromatographic separation, respectively. The analytes were monitored by a QTrap 5500 mass spectrometer with positive electrospray ionization.

Hair analysis, a reliable and non-invasive method to evaluate the contamination by clenbuterol.

The illegal use of clenbuterol has been an increasingly serious issue in today's livestock products industry. It becomes an important project to develop a reliable approach to detect its content in food animals. A simple and sensitive LC-MS/MS method was developed to detect clenbuterol residue in hair, with the low limit of quantitation (LLOQ) about 0.

Hyperlipidemia and atherosclerotic lesion development in Ldlr-deficient mice on a long-term high-fat diet.

Background: Mice deficient in the LDL receptor (Ldlr(-/-) mice) have been widely used as a model to mimic human atherosclerosis. However, the time-course of atherosclerotic lesion development and distribution of lesions at specific time-points are yet to be established. The current study sought to determine the progression and distribution of lesions in Ldlr(-/-) mice.

Contribution of carboxylesterase in hamster to the intestinal first-pass loss and low bioavailability of ethyl piperate, an effective lipid-lowering drug candidate.

Ethyl piperate is an effective lipid-lowering drug candidate synthesized from piperine. However, its pharmacokinetic characteristics and oral absorption process remain unclear. A liquid chromatography-tandem mass spectrometry method was applied to determine the oral bioavailability of ethyl piperate.

Pharmacokinetics of depside salts from Salvia miltiorrhiza in healthy Chinese volunteers: A randomized, open-label, single-dose study.

Background: Depside salts from Salvia miltiorrhiza, with active components of lithospermic acid B (LSB), rosmarinic acid (RA), and lithospermic acid (LA), are a multicomponent drug marketed in China for the treatment of coronary heart disease.

Objectives: The aims of this study were to determine the concentrations of LSB, RA, and LA in human plasma and urine, and to compare the pharmacokinetic properties of depside salts from S miltiorrhiza in healthy Chinese volunteers.

Methods: A randomized, open-label, single-dose study was conducted in healthy Chinese volunteers.

Liquid chromatography/tandem mass spectrometry for the determination of changrolin in rat plasma: application to a bioavailability study.

A sensitive and specific LC-CMS/MS method was developed for the quantification of changrolin, an anti-arrhythmic drug, in rat plasma using tiapride as internal standard. Liquid-liquid extraction was employed for sample preparation and analyzed using a multiple reaction monitoring mode with electrospray positive ionization source. The calibration curve for changrolin was linear over the range 5-1600 ng/mL with coefficients of correlation >0.

Pharmacokinetics and metabolism of lithospermic acid by LC/MS/MS in rats.

The pharmacokinetics and metabolism of lithospermic acid (LA), a component isolated from Salvia miltiorrhiza, and its two O-methylated metabolites (3'-monomethyl- and 3',3''-dimethyl-lithospermic acid), were analyzed by a rapid and specific isocratic liquid chromatography-tandem mass spectrometry (LC/MS/MS) method. Rat serum samples collected after intravenous and oral administration were analyzed for obtaining pharmacokinetic data of LA. Two O-methylated metabolites, namely one 3'-monomethyl- and one 3',3''-dimethyl-lithospermic acid were detected in rat serum and bile samples after intravenous and oral administration of LA, respectively.

Simultaneous determination of lithospermic acid B and its three metabolites by liquid chromatography/tandem mass spectrometry.

A rapid and sensitive method based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) was developed for the simultaneous determination of lithospermic acid B and its three main O-methylated metabolites in rat serum with silibinin as the internal standard. The calibration curves for LSB, and the three metabolites were linear over the ranges of 16-4096, and 8-2048 ng/ml, respectively, with coefficients of correlation >0.998.

Pharmacokinetics, tissue distribution, metabolism, and excretion of depside salts from Salvia miltiorrhiza in rats.

Salviae miltiorrhiza, a traditional Chinese medical herb known as "Danshen," has been widely used in clinics to improve blood circulation, relieve blood stasis, and treat coronary heart disease. Depside salts from S. miltiorrhiza are a novel drug in which magnesium lithospermate B and its analogs are the active components.