[Accumulation of microbial necromass carbon and their contribution to soil organic carbon in different vegetation types on the Loess Plateau, Northwest China].

Microbial necromass carbon (MNC) is an important contributor to soil organic carbon (SOC). Soil carbon storage has increased significantly since the return of farmland to forestland (grassland) on the Loess Plateau. However, the contribution of MNC to SOC accumulation in different vegetation types and the influence factors remain unclear.

Mechanism of polyethylene and biodegradable microplastic aging effects on soil organic carbon fractions in different land-use types.

Microplastics (MPs) are widely present in terrestrial ecosystems, but knowledge about the aging characteristics of MPs in different land-use types and their impact on soil organic carbon fractions is still limited. Polyethylene (PE) and biodegradable MPs (Poly propylene carbonate and Polybutylene adipate terephthalate synthetic material (PPC + PBAT, Bio)), at 0 %, 0.03 %, and 0.

Pharmacokinetic study of the main components of Tanreqing capsules and Tanreqing injections in beagles by liquid chromatography-tandem mass spectrometry.

Background: Tanreqing capsules (TRQCs) and Tanreqing injections (TRQIs) are widely used in the treatment of respiratory diseases. In this study, a simple, rapid, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous quantification of the main components of Tanreqing, which include chlorogenic acid, ursodeoxycholic acid, chenodeoxycholic acid, and baicalin, in beagle dog plasma to compare their pharmacokinetic parameters.

Methods: Plasma samples were pretreated with protein precipitation.

LC-MS/MS Method for Determination of Hydroxychloroquine and Metabolites: Application in a Pharmacokinetic Study.

Hydroxychloroquine (HCQ) was originally used as an antimalarial and immunomodulation drug. We developed and validated a simple and sensitive ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for simultaneous quantitation of HCQ and its three metabolites in rat blood, and reported their pharmacokinetic parameters. The chromatographic separation and detection of analytes were achieved within 4 min on ZORBAX SB-C (3.

A Direct and Sensitive Method for Determination of 5-Fluorouracil in Colorectal Cancer Cells: Evaluating the Effect of Stromal Cell on Drug Resistance of Cancer Cells.

Fibroblasts in the stroma play a critical role in tumor evolution. In this study, we assessed the influence of colonic fibroblasts on colon cancer cells treated with 5-fluorouracil (5-FU), and mouse colon cancer cell lines MC38 and colonic fibroblasts NIH3T3 were used in this study. A sensitive and rapid UHPLC-MS/MS method for the quantitation of 5-FU from the cell and their medium has been successfully developed and validated.

Human drug efflux transporter ABCC5 confers acquired resistance to pemetrexed in breast cancer.

Aim: Pemetrexed, a new generation antifolate drug, has been approved for the treatment of locally advanced or metastatic breast cancer. However, factors affecting its efficacy and resistance have not been fully elucidated yet. ATP-binding cassette (ABC) transporters are predictors of prognosis as well as of adverse effects of several xenobiotics.

A rapid and sensitive method for simultaneous determination of eight protein-bound uremic toxins in human serum by UHPLC-MS/MS: application in assessing peritoneal dialysis.

A simple, rapid, reliable and sensitive ultra-high performance liquid chromatography tandem spectrometry (UHPLC-MS/MS) method was established for determination of eight serum protein-bound uremic toxins (hippuric acid, indoxyl sulfate, indole-3-acetic acid, kynurenic acid, L-kynurenine, melatonin, 3-carboxy-4-methyl-5-propyl-2-furanpropionic acid, 4-hydroxyhippuric acid) in serum from chronic kidney disease (CKD) dialysis patients. The chromatographic separation was achieved on an Atlantis T3 column (3 μm, 2.1 mm × 100 mm) using a gradient elution with acetonitrile (phase B) and 0.