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M R Gasco

Publications and source records attributed to M R Gasco.

64 records · Page 4Linked to original sources
PubMed1976

[Complexes of pteridines with phenothiazine and phenoxazine derivatives].

Folic acid and pteroylaspartic acid form solid complexes with N-dialkylaminoalylphenothiazines and with N-dialkylaminoalkylphenoxazines. Folic acid forms 1:2 solid complexes with derivatives having the amine nitrogen in gamma position to heterocyclic nitrogen; the complexes are not formed with those derivatives in which the amine nitrogen is in the beta position to the heterocyclic nitrogen. Pteroylaspartic acid forms 1: 1 solid complexes with classes of compounds having aminic nitrogen in both gamma or beta position to the heterocyclic nitrogen.

Folic Acid↗
PubMed1976

[Charge-transfer complexes of hematoporphyrin with pteridine derivatives].

Charge-transfer complexes of hematoporphyrin with pteridine derivatives (folic acid, folinic acid, methotrexate) were studied in solutions buffered at pH 7.5 - 9 -10. The association constants for folic acid are pH dependent; at pH 7.5 the constant is 1240 wheras at pH 10 it is only 65. The association constant for folinic acid was determined only at pH 7.5 and was found to be 55. The association constants of methotexate are approximately the same at different pH's.

Buffers↗
PubMed1975

[Charge-transfer complexes of indolalkylamine and ergoline derivatives].

Charge-transfer complexes of 1,3,5-trinitrobenzene and pyromellitic dianhydride with indolalkylamines (5-hydroxytryptamine, dimethyltryptamine, etryptamine) and with ergoline derivatives having antiserotonin activity (methysergide, methylergometrine, metergoline, nicotergoline) were studied. The value of the association constant of indole derivatives with trinitrobenzene is influenced by variations on the chain; on the contrary, with pyromellitic dianhydride - only etryptamine and dimethyltryptamine form CT-complexes - the different behaviour can not be correlated with any particular structural characteristics. The association constant values of ergoline derivatives with trinitrobenzene are of the same order of magnitude as that of serotonin; with pyromellitic dianhydride only metergoline and nicotergoline form CT-complexes.

Metergoline↗
PubMedDate not supplied

Cholesteryl butyrate in solid lipid nanospheres as an alternative approach for butyric acid delivery.

BACKGROUND: Cholesteryl-butyrate chosen as lipid matrix of solid lipid nanospheres (SLNs) could be a suitable pro-drug to deliver butyric acid and overcome one of the most limiting disadvantages of the compound: the short half-life due to a rapid metabolism. METHODS: We evaluated the antiproliferative effect, with respect to that of sodium butyrate, of four SLNs (SLN1, SLN2, SLN3 and SLN4) characterized by a different concentration of cholesteryl-butyrate (range, 1.7-30 mM) on NIH-H460, a non-small cell lung carcinoma cell line. RESULTS: After 6 days of treatment, all SLN preparations induced a dose-dependent inhibition of NHI-H460 cell growth: the most effective SLN preparation (SLN1) was able to induce a complete growth inhibition already at 0.25 mM, a concentration at which sodium butyrate induced only a 55% inhibition. Fluorescence microscopy showed that 6-coumarin-tagged SLNs were almost completely internalized by cells after 5 min of treatment. CONCLUSIONS: The present results indicate that owing to their peculiar characteristics, SLNs could be an interesting alternative approach for butyric acid delivery into tumor cells.

Butyrates↗
PubMedDate not supplied

In vitro transdermal permeation of nifedipine from thickened microemulsions.

The in vitro transdermal absorption of nifedipine from microemulsions was studied using the skin of the hairless mouse as membrane. Two microemulsions (N.1 and N.2) were prepared and thickened; they contained respectively 1.8% and 2.0% of nifedipine in solution. The fluxes of the drug from the microemulsions were 7.8 micrograms/h/cm2 from N.1 and 18.6 micrograms/h/cm2 from N.2. Two reference gels were prepared to examine whether the components of the microemulsion could behave as enhancer: their fluxes were very low, below 0.5 microgram/h/cm2. Nifedipine dissolved in microemulsion and protected from light showed no degradation for up to six months.

Administration, Cutaneous↗