Isoniazid (INH), a widely used first-line antitubercular drug, has been noted to be associated with hepatotoxicity. In spite of extensive researches over many decades, the mechanism of INH-induced hepatotoxicity still remains poorly understood. Recently, mitochondrial toxicity has been emerging as a new paradigm for INH-induced hepatotoxicity. In this study, we showed that INH impaired mitochon...

We evaluated thin-layer agar (TLA) for the detection of resistance of Mycobacterium tuberculosis to rifampicin (RMP) and isoniazid (INH) as a direct method in patients at risk of multidrug-resistant tuberculosis (MDR-TB). Quadrant TLA plates contain 7H10 Middlebrook growth control, para-nitrobenzoic acid, INH and RMP. Detection of RMP and INH resistance by TLA was compared to that in indirect c...

During the course of horseradish peroxidase-mediated oxidation of either o-dianisidine or 2-2'-azino-di(3-ethyl-benzthiazoline-6-sulfonic acid) (ABTS), no O2 consumption took place. When isonicotinic acid hydrazide (isoniazid) (INH) was included in the reaction mixture, O2 was consumed in amounts linearly related to the INH concentration. Nicotinic acid hydrazide at equimolar concentrations ind...

Two antimycobacterial drugs ethambutol (EMB) and isoniazid (INH) were found to result in decreases of biomechanical properties including adhesion force, cell wall spring constant, and Young's modulus in Mycobacterium sp. strain JLS (M. JLS).

In 1952 the clinical use of pyrazinamide (PZA) was first reported by Yeager, Munroe, and Dessa&. In 1954 McCune, Tompsett, and McDermott2 observed that the combined use of isoniazid and pyrazinamide in the treatment of pulmonary tuberculosis was especially effective. Isoniazid (INH) and pyrazinamide have been employed at the San Fernando Veterans Administration Hospital since 1952, but not unti...

A series of twenty-three N-acylhydrazones derived from isoniazid (INH 1-23) have been evaluated for their in vitro antibacterial activity against INH- susceptible strain of M. tuberculosis (RG500) and three INH-resistant clinical isolates (RG102, RG103 and RG113). In general, derivatives 4, 14, 15 and 16 (MIC=1.92, 1.96, 1.96 and 1.86 µM, respectively) showed relevant activities against RG500 s...

Isonicotinic acid hydrazide (isoniazid; INH) inhibition of mycolic acid synthesis was studied by using cell extracts from both INH-sensitive and -resistant strains of Mycobacterium aurum. The cell extract of the INH-sensitive strain was inhibited by INH, while the preparation from the INH-resistant strain was not. This showed that the INH resistance of mycolic acid synthesis was not due to a di...

OBJECTIVES Isoniazid (INH) is one of the main first line drugs used in treatment of tuberculosis and development of resistance against this compound can result in serious problems in treatment procedures. Resistance to INH is mediated mainly by mutation in KatG gene that is coded for the catalase enzyme. The proportional method for detection of INH-resistance is time consuming due to the slow g...

The study sought to determine the rate of discordant results between genotypic and phenotypic tests for diagnosis drug-resistant tuberculosis (DR-TB). Sputum samples cultured isolates from suspected DR-TB patients were, respectively, analyzed Mycobacterium by Xpert® MTB/RIF (Cepheid, Sunnyvale, CA, USA) line probe assays (LPA) (Hain, Nehren, Germany). Discrepant rifampicin (RMP)-resistant were ...

Background. Analysis of isoniazid (INH) uptake has been based on measurement of plasma concentrations providing a short-term and potentially biased view. Objectives. To establish hair analysis as a tool to measure long-term uptake of INH and to assess whether acetylator phenotype in hair reflects N-acetyltransferase-2 (NAT2) genotype. Design and Methods. INH and acetyl-INH concentrations in hai...