Transfer-messenger RNA and SmpB mediate bacteriostasis in Escherichia coli cells against tRNA cleavage.

RNAs, such as mRNA, rRNA and tRNA, are essential macromolecules for cell survival and maintenance. Any perturbation of these molecules, such as by degradation or mutation, can be toxic to cells and may occasionally induce cell death. Therefore, cells have mechanisms known as quality control systems to eliminate abnormal RNAs.

Enantioselective and highly sensitive determination of carvedilol in human plasma and whole blood after administration of the racemate using normal-phase high-performance liquid chromatography.

A highly sensitive HPLC method for enantioselective determination of carvedilol in human whole blood and plasma was developed. Carvedilol and S-carazolol as an internal standard extracted from whole blood or plasma were separated using an enantioselective separation column (Chiralpak AD column; 2.0 diameter x 250 mm) without any chiral derivatizations.