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Instituto de Higiene e Medicina Tropical

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Viveiros M

Effective therapy with the neuroleptic thioridazine as an adjunct to second line of defence drugs, and the potential that thioridazine offers for new patents that cover a variety of “new uses”.

New and active infections of tuberculosis continue to increase globally. Although antibiotic susceptible infections can be readily cured with isoniazide and rifampicin, infections resistant to these two antibiotics, named Multi-Drug Resistant TB (MDR TB), are problematic for therapy, extol high costs in terms of human suffering and finances, and when these MDR infections progress to Extensive Drug Resistant TB (XDR TB) status, they are not only difficult to treat, they produce high levels of mortality regardless of therapeutic modality employed.
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Direct modification of bioactive phenothiazines by exposure to laser radiation.

Whereas exposure of combinations of a phenothiazine and bacterium to incoherent UV increases the activity of the phenothiazine, exposure of the phenothiazine alone does not yield an increase of its activity. Because the laser beam energy is greater than that produced by the incoherent UV sources, exposure of phenothiazines to specific lasers may yield molecules with altered activities over that of the unexposed parent.
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Ethidium bromide efflux by Salmonella: modulation by metabolic energy, pH, ions and phenothiazines

The main efflux pump of Salmonella enterica serotype Enteritidis, which obtains its energy for the extrusion of noxious agents from the proton-motive force, was studied with the aid of an ethidium bromide (EtBr) semi-automated method under conditions that define the role of metabolic energy, ions and pH in the extrusion of the universal substrate EtBr.
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Identification of nontuberculous mycobacteria in clinical samples using molecular methods: a 3-year study

Nontuberculous mycobacteria (NTM) are being increasingly isolated in clinical laboratories and present technical and therapeutic challenges.
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Identification of the plasmid-encoded qacA efflux pump gene in meticillin-resistant Staphylococcus aureus (MRSA) strain HPV107, a representative of the MRSA Iberian clone

Meticillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial bacterium for which prevention and control measures consist mainly of the application of biocides with antiseptic and disinfectant activity.
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Quinazoline derivatives are efficient chemosensitizers of antibiotic activity in Enterobacter aerogenes, Klebsiella pneumoniae and Pseudomonas aeruginosa resistant strains

Amongst the three series of quinazoline derivatives synthesised and studied in this work, some molecules increase the antibiotic susceptibility of Gram-negative bacteria presenting multidrug-resistant phenotypes.
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Measuring efflux and permeability in mycobacteria

The intrinsic resistance of mycobacteria to most antimicrobial agents is mainly attributed to the synergy between their relatively impermeable cell wall and efflux systems. The mycobacterial cell wall is rich in lipids and polysaccharides making a compact envelope that limits drug uptake.
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Nested and Multiplex Real-Time PCR Using Dual-Labeled Probes: Detecting and Discriminating Mycobacterium tuberculosis Complex Members in Cultures and Animal Tissues

Members of the Mycobacterium tuberculosis complex (MTC) are causative agents of tuberculosis (TB) in both humans and animals. In the last two decades, the accumulating knowledge of the nucleotide sequences of several genes, and of the whole genomes, of MTC members has allowed the development of novel molecular assays able to detect and discriminate between these species.
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