Development and validation of an LC-MS/MS multiplex assay for the quantification of bedaquiline, n-desmethyl bedaquiline, linezolid, levofloxacin, and clofazimine in dried blood spots.

Dried blood spot (DBS) assays to quantify novel and repurposed drugs for the treatment of rifampicin-resistant tuberculosis (RR-TB) would facilitate pharmacokinetic studies and therapeutic drug monitoring in low-middle income settings, considering their ease of application and simple sample storage requirements. We describe a DBS method for the simultaneous quantification of bedaquiline and metabolite N-desmethyl bedaquiline, linezolid, levofloxacin, and clofazimine. The analytes were extracted from the matrix and isolated by solid-phase extraction.

Development and validation of a liquid chromatography-tandem mass spectrometry assay for the simultaneous analysis of isoniazid and pyrazinamide in cerebrospinal fluid.

For the effective treatment of tuberculosis with first-line anti-tubercular drugs, drug concentrations need to be measured at the site of infection to determine drug exposure. To enable the measurement of the anti-tuberculosis drugs isoniazid and pyrazinamide in the nervous system of patients with tuberculous meningitis, an analytical method was developed and validated for the quantification of these drugs in human cerebrospinal fluid. Samples were prepared by solid phase extraction using Strata-X polymeric extraction plates.

Mapping and engineering RNA-controlled architecture of the multiphase nucleolus.

Biomolecular condensates are key features of intracellular compartmentalization. As the most prominent nuclear condensate in eukaryotes, the nucleolus is a layered multiphase liquid-like structure and the site of ribosome biogenesis. In the nucleolus, ribosomal RNAs (rRNAs) are transcribed and processed, undergoing multiple maturation steps that ultimately result in formation of the ribosomal small subunit (SSU) and large subunit (LSU).

Interim analysis, a tool to enhance efficiency of pharmacokinetic studies: Pharmacokinetics of rifampicin in lactating mother-infant pairs.

Pharmacokinetic studies are important for understanding drug disposition in the human body. However, pregnant and lactating women are often excluded from primary pharmacokinetic studies and as such there is often limited dosing information regarding drug use in pregnant and/or lactating women. The objectives of this interim analysis were to define the transfer of rifampicin to a breastfed infant and to determine the area under the concentration-time curve of rifampicin in maternal plasma, breastmilk and infant plasma.