The interaction of ten natural polyphenolic compounds (chlorogenic acid, apigenin, catechin, epicatechin, flavanone, flavone, quercetin, rutin, vicenin-2 and vitexin) with human serum albumin and mixtures of human serum albumin and α(1)-acid glycoprotein under near physiological conditions is studied by capillary electrophoresis-frontal analysis. Furthermore, the binding of these polyphenolic compounds to total plasmatic proteins is evaluated using ultrafiltration and capillary electrophoresis. In spite of the relatively small differences in the chemical structures of the compounds studied, large differences were observed in their binding behaviours to plasmatic proteins. The hydrophobicity, the presence/absence of some functional groups, steric hindrance and spatial arrangement seem to be key factors in the affinity of natural polyphenols towards plasmatic proteins.

The aim of the present study was to evaluate the in vitro activity of baicalein, the flavone constituent of Scutellaria baicalensis, and synergism of the combination of baicalein and fluconazole against Candida albicans, Candida tropicalis and Candida parapsilosis. The MIC 50 (lowest concentration at which there was 50 % inhibition of growth) of baicalein alone against six Candida strains ranged from 13 to 104 mg ml "1 . For the three species tested, exposure to baicalein at the MIC 50 concentrations obtained for each strain resulted in a high loss of viability. The fluconazole plus baicalein combination markedly reduced the MICs of both drugs for all three strains analysed. In addition, a synergistic effect between baicalein and fluconazole was observed for C. parapsilosis in terms of MIC 50 (fractional inhibitory concentration index50.207). Scanning electron microscopy analysis revealed that yeast cells exposed to baicalein at MIC 50 produced a profusely flocculent extracellular material, resembling a biofilm-like structure. In conclusion, these results showed the antifungal capability of baicalein against Candida species and highlight a promising role of baicalein when used in combination with fluconazole against Candida infections. INTRODUCTIONCandidiasis is one of the most common fungal infections in humans caused by Candida species, most notably by Candida albicans. Currently, other species of this genus have been found to cause an increasing number of cases of candidiasis (Mokaddas et al., 2007;Pereira et al., 2010;Das et al., 2011).The therapy of invasive candidiasis remains a difficult medical problem. Despite the availability of extendedspectrum triazoles, the incidence of invasive infections and resistance to antifungal therapy continue to increase (Pfaller & Diekema, 2010). Widespread use of antifungal agents could be an explanation for the emergence of the more resistant non-albicans species of Candida, such as Candida glabrata (reviewed by Kothavade et al., 2010; Silva et al., 2012).The azole fluconazole is effective against most Candida species and is used currently as a first-line drug, although different degrees of susceptibility among species have been described. For instance, C. glabrata is inherently less susceptible to fluconazole. In addition, the emergence of fluconazole resistance has been reported in species typically susceptible to this agent, such as C. albicans, Candida tropicalis and Candida parapsilosis (Hajjeh et al., 2004;Yang et al., 2004;Lyon et al., 2010;Oxman et al., 2010; Arendrup et al., 2011), including that observed in Brazilian tertiarycare hospitals (Bruder-Nascimento et al., 2010;Favalessa et al., 2010;Pereira et al., 2010;Furlaneto et al., 2011).These factors present an urgent need to search for novel compounds with anticandidal activity. To this end, efforts have been made in the search for novel antifungal agents from various natural sources. In this regard, baicalein (5,6,7-trihydroxyflavone; Fig. 1) is a flavonoid originally isolated from the roots of the Chine...

Aims To evaluate the relative bioavailability of oral amoxicillin (AMX) tablets in comparison to AMX suspension in Roux‐en‐Y gastric bypass bariatric subjects. Methods A randomized, double‐blind, cross‐over study was performed on the bioavailability of oral AMX tablets and suspension in Roux‐en‐Y gastric bypass subjects operated at least 3 months previously . Doses of 875 mg of the AMX tablet or 800 mg of the AMX suspension were given to all the subjects, allowing a washout of 7 days between the periods. Blood samples were collected at 0, 0.25, 0.5, 1, 1.5, 2, 4, 6 and 8 hours after drug administration and the AMX levels were quantified by liquid chromatography coupled with triple quadrupole tandem mass spectrometry. The pharmacokinetic parameters were calculated by noncompartmental analysis, normalized to an 875 mg dose and the bioavailability of the AMX from the tablets was compared to that from the suspension formulation. Results Twenty subjects aged 42.65 ± 7.21 years and with a body mass index of 29.88 ± 4.36 kg/m2 were enrolled in the study. The maximum AMX plasma concentration of the tablets and the suspension (normalized to 875 mg) were 7.42 ± 2.99 mg/L and 8.73 ± 3.26 mg/L (90% confidence interval of 70.71–99.11), and the total area under the curve from time zero to infinity were 23.10 ± 7.41 mg.h/L and 27.59 ± 8.32 mg.h/L (90% confidence interval of 71.25–97.32), respectively. Conclusion The tablets presented a lower bioavailability than the suspension formulation and the total absorbed amount of AMX in these subjects was lower in comparison to the standard AMX absorption rates in nonbariatric subjects, regardless of the formulation.

The data obtained from the system composed of 20% Polox, 0.15% Carb, and 0.25% MB indicated a potentially functional role in PDT of the colorectal cancer and suggest it is worthy of clinical evaluation.