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Martins A

Non-antibiotics reverse resistance of bacteria to antibiotics.

BACKGROUND: Most clinical isolates that exhibit a multi-drug resistant phenotype owe that resistance to over-expressed efflux pumps. Compounds that are efflux pump inhibitors (EPIs) reduce or reverse resistance to antibiotics to which the bacterial strain is initially resistant. We have evaluated non-antibiotics to reduce resistance of commonly encountered bacterial pathogens to antibiotics. MATERIALS AND METHODS: […]
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Role of calcium in the efflux system of Escherichia coli.

Efflux of antibiotics by Escherichia coli AG100 is performed by a variety of efflux pumps, ensuring survival of the bacterium in widely diverse media. At pH 5, efflux is independent of metabolic energy during the period of time the assay is conducted; at pH 8 it is totally dependent upon metabolic energy.
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Genetic response of Salmonella enterica serotype Enteritidis to thioridazine rendering the organism resistant to the agent.

Thioridazine (TZ)-induced accumulation of the universal efflux pump substrate ethidium bromide and its subsequent efflux by Salmonella strains with various degrees of overexpressed efflux pumps takes place automatically at pH 7.4, is independent of a metabolic source, is not affected by a proton ionophore and is precluded by palmitic acid.
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Phenothiazines, bacterial efflux pumps and targeting the macrophage for enhanced killing of intracellular XDRTB

Phenothiazines have their primary effects on the plasma membrane of prokaryotes and eukaryotes. Among the components of the prokaryotic plasma membrane affected are efflux pumps, their energy sources, energy providing enzymes such as ATPases, and genes that regulate and code for permeability aspects of the bacterium.
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Competition between substrates of the efflux pump system of Salmonella enteritidis.

AIM:
To determine whether tetracycline competes with ethidium bromide (EB), used as substrate of efflux pumps, for extrusion by the efflux pump system of Salmonella enteritidis NCTC 13349 reference strain.
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Feline Leishmania infection in a canine leishmaniasis endemic region, Portugal

Canine leishmaniasis (CanL) caused by Leishmania infantum is a serious zoonotic public health and veterinary problem in the Mediterranean basin. Leishmania infection in domestic cats (Felis catus domesticus) has been reported in several countries where this zoonosis is endemic, such as Portugal, Spain, Italy, France, Greece, Israel, Palestine and Brazil. The aim of this study […]
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Activity of fourteen new hydantoin compounds on the human ABCB1 efflux pump.

BACKGROUND:
Multidrug resistance (MDR) is one of the major concerns in the treatment of cancer and one of the major causes of therapy failure. The overexpression of an ABC transporter, the ABCB1, is often associated with MDR in cancer. Previously it was observed that hydantoin compounds can modulate the activity of the ABCB1 pump.
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Inhibition of efflux pumps in methicillin-resistant Staphylococcus aureus and Enterococcus faecalis resistant strains by triterpenoids from Momordica balsamina.

Six cucurbitane-type triterpenoids (1-6) isolated from the aerial parts of Momordica balsamina were evaluated for their ability to inhibit the activity of bacterial efflux pumps of methicillin-resistant Staphylococcus aureus (MRSA) COL(OXA), Enterococcus faecalis ATCC 29212, Salmonella enterica subsp.
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