Validation of LC-MS/MS methods for quantitative analysis of kynurenine pathway metabolites in human plasma and cerebrospinal fluid.

Dysregulation of the kynurenine metabolic pathway has been reported in several neurological conditions. Sensitive and selective LC-MS/MS methods have been validated for six kynurenine pathway metabolites in human cerebrospinal fluid and plasma. For each matrix, we validated three methods - one for the simultaneous determination of kynurenine, kynurenic acid, anthranilic acid and 3-hydroxy-kynurenine (four-analyte assay), one for quinolinic acid and one for tryptophan - using stable-isotopically labeled internal standards.

A sensitive LC-MS/MS method for simultaneous quantification of ulotaront and its N-desmethyl metabolite in human plasma and application to a clinical study.

Ulotaront (SEP-363856) is a novel non-D2-receptor-binding agent under development for the treatment of patients with schizophrenia. A highly sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with lower limit of quantitation of 0.0200 ng/mL (i.

Use of venoarterial extracorporeal membrane oxygenation in fulminant chagasic myocarditis as a bridge to heart transplant.

A 17-year-old Brazilian male presented with progressive dyspnea for 15 days, worsening in the last 24 hours, and was admitted in respiratory failure and cardiogenic shock, with multiple organ dysfunctions. Echocardiography showed a left ventricle ejection fraction of 11%, severe diffuse hypokinesia, and a systolic pulmonary artery pressure of 50mmHg, resulting in the need for hemodynamic support with dobutamine (20mcg/kg/min) and noradrenaline (1.7mcg/kg/min).

Determination of carboplatin in human plasma using HybridSPE-precipitation along with liquid chromatography-tandem mass spectrometry.

The main purpose of this study was to develop and validate a rapid, specific, sensitive, and reliable LC-MS/MS-based bioanalytical method for the determination of carboplatin in human plasma. The optimal chromatographic behavior of carboplatin was achieved on a Biobasic SCX column (50 mm × 2.1 mm, 5 μm) using ion exchange chromatography.

Optimization and utilization of the SureFire phospho-STAT5 assay for a cell-based screening campaign.

The family of signal transducers and activators of transcription (STATs) consists of seven transcription factors that respond to a variety of cytokines, hormones, and growth factors. STATs are activated by tyrosine phosphorylation, which results in their dimerization and translocation into the nucleus where they exert their effect on transcription of regulated target genes. The phosphorylation of STATs is mediated mainly by Janus kinases (JAKs).