Comparison of PCR-heteroduplex characterization by automated DNA sequencing and line probe assay for the detection of rifampicin resistance in Mycobacterium tuberculosis isolates from KwaZulu-Natal, South Africa.

Progress in understanding the basis of resistance to rifampicin (RifR) has allowed molecular tests for the detection of drug-resistant tuberculosis to be developed. One hundred thirteen strains of Mycobacterium tuberculosis isolated from patients with multidrug resistant tuberculosis (MDR-TB) were investigated for genotypic analysis of RifR by polymerase chain reaction-heteroduplex formation (PCR-HDF) and characterization of mutations by automated DNA sequencing of the rpoB gene. A subset of isolates (22) representative of different mutations as confirmed by sequence analysis were also evaluated by the Line Probe Assay (LiPA). In 106 of the RifR strains, 24 mutations within an 81-bp region of the rpoB gene affecting 13 amino acids were observed. Most isolates (7/8) harboring Leu533 --> Pro codon mutation required minimum inhibitory concentrations (MICs) of < or = 8 microg/ml. There was geographic variation in the frequency of occurrence of particular rpoB mutations, with the Ser531 --> Leu/Trp codon mutation found in 59/113 of isolates. Although there are certain limitations in the use of both the rapid PCR-HDF diagnostic assay and the LiPA for the detection of rifampicin susceptibility of M. tuberculosis, these provide important and convenient tools for identifying and managing patients with MDR-TB.

Hyperlipidemia, dyslipoproteinemia and apolipoproteinopathia--classification and risk of atheroslcerosis. Part I: Principles of classification and methods of dyslipoproteinemia determination.

This paper sums up new findings in the field of pathogenetic relations between lipid and lipoprotein metabolical disorders on the one hand and the risk of early forms of atherosclerosis on the other hand. Detail classification of disorders proceeds from precise clinical and biochemical criteria, genetic considerations and therapeutical aspects. It provides definitions of hyperlipidemia, hyperlipoproteinemia, normolipidemic (latent) dyslipoproteinemia, secondary hyperlipidemia, apolipoproteinopathia and relatively harmless (benign) hyperlipidemia. The paper provides detail tables and systematic graphs.