Tropical shrubs living in an extreme environment show convergent ecological strategies but divergent ecophysiological strategies.

Background And Aims: Trait-based frameworks assess plant survival strategies using different approaches. Some frameworks use functional traits to assign species to a priori defined ecological strategies. Others use functional traits as the central element of a species ecophysiological strategy.

Evaluation of the BacT/ALERT PZA kit in comparison with the BACTEC 460TB PZA for testing Mycobacterium tuberculosis susceptibility to pyrazinamide.

Objectives: To compare the performance of the BacT/ALERT PZA kit (BioMerieux, Marcy l'Etoile, France) with the radiometric BACTEC 460TB PZA test (Becton-Dickinson method) for testing Mycobacterium tuberculosis susceptibility to pyrazinamide.

Methods: A total of 50 M. tuberculosis strains were tested.

Multicenter laboratory evaluation of the MB/BacT Mycobacterium detection system and the BACTEC MGIT 960 system in comparison with the BACTEC 460TB system for susceptibility testing of Mycobacterium tuberculosis.

In this multicenter study, the reliability of two nonradiometric, fully automated systems, the MB/BacT and BACTEC MGIT 960 systems, for testing the susceptibilities of 82 Mycobacterium tuberculosis strains to isoniazid, rifampin, ethambutol, and streptomycin was evaluated in comparison with the radiometric BACTEC 460TB system. The arbitration of discrepant results was done by the reanalysis of the strain, the determination of the MIC, and the molecular characterization of some resistance determinants. The overall level of agreement with BACTEC 460TB results was 96% with the MB/BacT test and 97.

Rapid detection of specific gene mutations associated with isoniazid or rifampicin resistance in Mycobacterium tuberculosis clinical isolates using non-fluorescent low-density DNA microarrays.

Background: A new, fast 'low cost and density' DNA microarray (LCD array), designed for the detection of mutations that confer isoniazid or rifampicin resistance in Mycobacterium tuberculosis isolates, has been developed and was evaluated using 46 resistant clinical isolates from Barcelona.

Methods: LCD chips are pre-structured polymer supports using a non-fluorescent detection principle based on the precipitation of a clearly visible dark substrate. One LCD chip consists of eight identical microarrays, designed to detect mutations within the 90 bp rpoB region, codon 315 in the katG gene and the mabA-inhA regulatory region.

Molecular analysis of isoniazid and rifampin resistance in Mycobacterium tuberculosis isolates recovered from Barcelona.

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.

Direct detection in clinical samples of multiple gene mutations causing resistance of Mycobacterium tuberculosis to isoniazid and rifampicin using fluorogenic probes.

Background: This study evaluates a method based on real-time PCR for direct detection in clinical samples of the common mutations responsible for isoniazid and rifampicin resistance of Mycobacterium tuberculosis.

Methods: Six pairs of fluorogenic 5' exonuclease probes (Taqman), mutated and wild-type, were designed for six targets: codon 315 of katG, substitution C209T in the regulatory region of inhA, and codons 513, 516, 526 and 531 of rpoB.

Results: A total of 98 clinical samples harbouring resistant bacilli from 55 patients and 126 samples harbouring susceptible bacilli from 126 patients were processed.

[Occurrence of Listeria monocytogenes in pre-sliced vacuum-packaged].

There is scarce information in Brazil and other South American countries about the occurrence of Listeria monocytogenes in food, mainly refrigerated ready-to-eat products. The consumption of sliced vacuum-packaged meat products has increased in the last few years. Nevertheless, a complete assessment of the risk associated with L.