The effects of pneumolysin on the proinflammatory activity of human neutrophils, as well as on cation fluxes in these cells, have been investigated. Superoxide production, release of elastase, CR3 expression, phospholipase A2 activity, and alterations in membrane potential were measured by use of lucigenin-enhanced chemiluminescence and colorimetric, flow cytometric, radiometric, and spectroflu...

The fluorescence enhancement of berberine hydrochloride (BBH) as a result of complex with β-cyclodextrin (β-CD) is investigated. The mechanism of the inclusion was studied and discussed by spectrofluoremetry and infrared spectrograms. The results showed that a 1∶1 (β-CD: BBH) complex was formed with an apparent association constant of 4.23×10(2) L/mol. Based on the enhancement of the fluorescen...

An endogenous chromophore regularly associated with rat alpha 1 fetoprotein was detected by a systematic study of the fluorescence spectra of the protein purified by immunoabsorption. This fluorescent ligand, of low molecular weight, was dissociated from rat alpha 1 fetoprotein by exhaustive dialysis of the protein at low concentration. A phase partition method with aqueous preparations of rat ...

A simple and sensitive spectrofluorimetric method was developed for the determination of biotin in pure form and in pharmaceutical preparations. The proposed method is based on the oxidation of the drug with cerium (IV) ammonium sulfate in acidic medium. The fluorescence of the produced Cerium (III) was measured at 365 nm after excitation at 255 nm. The different experimental parameters affecti...

The synthesis and characterization of the new chiral ligand 2, based on a BINOL-tren (tren = tris(2-aminoethyl)amine) conjugate, in enantiomerically pure form, are reported. UV-Vis spectrophotometric and spectrofluorimetric studies at variable pH show that the incorporation of a phenolic functionality in close proximity to the polyamino fragment of the molecule causes a dramatic variation of th...

The interaction between zaleplon (ZAL) and different cyclodextrins in aqueous solutions was investigated by spectrofluorimetric and phase solubility studies. Stability constants determined by both methods showed that among natural cyclodextrins, β-cyclodextrin (βCD) formed the most stabile complex but its solubilizing efficiency was limited. Among βCD derivatives, the complex stability and solu...

Two simple and sensitive spectrofluorimetric methods have been developed for the determination of labetalol (LBT). In method A, the native fluorescence was measured at 432 nm after excitation at 312 nm. The second method (method B) is based on the formation of a ternary complex between zinc (II), eosin and LBT. The fluorescence intensity of the ternary complex was measured at 452 nm after excit...

The effect of several surfactants on the formation of the fluorescent ternary complex oxalate-Alizarin Red S-zirconium(IV) has been studied. In weakly acidic medium and in the presence of cationic surfactants, such as cetylpyridinium chloride, total complex formation is achieved, whereas in aqueous medium or in the presence of non-cationic micelles no significant changes are obtained in compari...

Advanced glycation endproducts (AGE) are the result of post-translational changes to proteins, which ultimately compromise their structure and/or function. The identification of methods to prevent the formation of these compounds holds great promise in the development of alternative therapies for diseases such as diabetes. Plants used in traditional medicine are often rich sources of anti-glyca...

The aim of the study was to assess stress on the basis of the excretion rates of stress hormones in occupational groups under mental stress. The investigation includes 293 persons, working in power engineering, education, public health and information sector. The stress hormones adrenaline, noradrenaline and 11-oxycorticosteroids (11-OCS) were followed during the working day using spectrofluori...