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Amaral L

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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Rapid, laser-induced conversion of 20-hydroxyecdysone and its diacetonide — experimental set-up of a system for photochemical transformation of bioactive substances.

BACKGROUND:
Photochemical transformation of certain bioactive compounds for the purpose of obtaining derivatives with increased bioactivity is a prospective area of synthetic chemistry. Ecdysteroids, analogs of the insect molting hormone, which can also exert several beneficial effects in mammals including humans, contain an enone moiety in their B ring, and, as such, are good candidates for photochemical transformations.
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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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In vitro cytotoxic activity of novel protoflavone analogs – selectivity towards a multidrug resistant cancer cell line.

BACKGROUND:
Protoapigenone (PA), a natural flavonoid possessing an unusual p-quinol moiety on its B ring, is a prospective novel lead compound against cancer currently in development, together with WYC0209, a potent synthetic PA analog. Structure activity relationships (SAR) concerning different 1′-O-alkyl side-chains were also studied on two sets of derivatives.
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Inhibitors of bacterial efflux pumps that also inhibit efflux pumps of cancer cells.

Bacteria and cancer cells frequently increase their resistance to chemotherapeutics as a consequence of therapy. Whenever studied, refractory response to chemotherapy is due to the over-expression of efflux pumps that render the bacterium or cancer cell resistant not only to the agent used for therapy, but to many, if not all other agents as well.
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Thioridazine protects the mouse from a virulent infection by Salmonella enterica serovar Typhimurium 74

When administered to mice at doses of 100microg/mouse and 200microg/mouse, thioridazine (TDZ) significantly protected animals from the lethality produced by a virulent strain of Salmonella enterica serovar Typhimurium and reduced the number of bacteria retrieved from the spleen, liver and heart blood.
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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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An original deal for new molecule: reversal of efflux pump activity, a rational strategy to combat gram-negative resistant bacteria.

The worldwide dissemination of «multi-drug resistant» (MDR) pathogens has severely reduced the efficacy of our antibiotic arsenal and increased the frequency of therapeutic failure. MDR bacteria over-express efflux pumps and this active mechanism can extrude all classes of antibiotics from the cell.
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Optical investigation of medicine solutions in micro-droplets form at interaction with laser radiation.

One of the alternatives to the existing medicines and treatment procedures in fighting multi drug resistance (MDR) is strengthening the effects of medicines by modifying their molecular structures through exposure to laser radiation.
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