Reverse transcription-polymerase chain reaction (RT-PCR) and quantitative, competitive RT-PCR were used to examine the capability of rifampin to induce the expression of mRNA derived from multidrug resistance-1 (MDR1) and drug-metabolizing cytochrome P450 (P450) genes in the mononuclear fraction (lymphocytes) of human blood. A total of 50 healthy volunteers (age, 18-74) participated in two stud...

The correlation between resistance to pyrazinamide (PZA) and resistance to other first-line antituberculosis drugs was investigated in 395 Mycobacterium tuberculosis strains isolated from clinical specimens, representing 14% of the overall number of M. tuberculosis isolates obtained between 2003 and 2008 at the laboratory of a referral university hospital for tuberculosis. A high correlation wa...

Tubercular uveitis (TBU) is a common cause of infectious uveitis in countries where tuberculosis is endemic. Molecular diagnostic techniques are the cornerstone of diagnosis as of now, as culture positivity has never been reported to date. With increasing reports of multidrug-resistant tuberculosis (MDR TB) from various extrapulmonary sites and in the light of a recent case report (1), there is...

We studied the presence of mutations in the whole katG gene and specific regions of the oxyR-ahpC and mabA-inhA regulatory region in 61 Mycobacterium tuberculosis isoniazid-resistant isolates. An 81-bp region of the rpoB gene was also sequenced in 17 rifampin-resistant strains. Alterations in the katG gene were detected in 55% of the isolates. Mutation in codon 315 was the most prevalent (32%)....

Pregnane X receptor (PXR) has been reported to regulate the expression of drug-metabolizing enzymes, such as the cytochrome P450 3A (CYP3A) family and transporters, such as multiple drug resistance 1 (MDR1). Fucoxanthin, the major carotenoid in brown sea algae, is a putative chemopreventive agent. In this study, we determined whether fucoxanthin could overcome drug resistance through attenuatio...

Evidence is mounting that epistasis is widespread among mutations. The cost of carrying two deleterious mutations, or the advantage of acquiring two beneficial alleles, is typically lower that the sum of their individual effects. Much less is known on epistasis between beneficial and deleterious mutations, even though this is key to the amount of genetic hitchhiking that may occur during evolut...

There are 30 of bacterial samples were isolated from 45 different infections. These isolates diagnosed microscopically and by using biochemical tests. ability their resistance was tested against the following antibiotics: (amoxicillin, tetracycline, cephalexin, nitrofurantoin, ciprofloxacin, clarithromycin, erythromycin, ampicillin, rifampin), for detection sites genes encoding antibiotic , con...

BACKGROUND Based on a hollow-fiber system model of tuberculosis, we hypothesize that microbiologic failure and acquired drug resistance are primarily driven by low drug concentrations that result from pharmacokinetic variability. METHODS Clinical and pharmacokinetic data were prospectively collected from 142 tuberculosis patients in Western Cape, South Africa. Compartmental pharmacokinetic pa...