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The aim of this study was to characterize the stability of new vehicles for the undecylenoyl phenylalanine that is used as skin-lightening agent in the melasma treatment. The purpose of this research was also to analyse the release kinetics of phenylalanine derivative from topical preparations through different synthetic membranes. Topical formulations such as two different macroemulsions, hydrogels (based on carbomer and hydroxyethylcellulose) and microemulsions were characterized in terms of stability by laser diffraction method. Additionally, multiple light scattering assessed the stability of macroemulsions. The release rates of active substance through different membranes (such as Cuprophan, nitrocellulose, cellulose acetate and Strat-M) were determined using enhancer cell. In order to explain the mechanism of release process the results were fitted with different kinetic models. New stable vehicles for Ude-Phe were successfully obtained. The results proved that the membrane structure had the influence on the release rate of undecylenoyl phenylalanine. The slowest release rate of Ude-Phe was observed when Strat-M membrane was applied. The highest amount of active substance was released from the hydrogel based on carbomer. The release of undecylenoyl phenylalanine from both macroemulsions and hydrogel based on hydroxyethylcellulose followed the Higuchi model. Whereas the release results of Ude-Phe from both microemulsion-based hydrogels and carbomer hydrogel can be described by using Korsmeyer-Peppas model. Hydrogels and microemulsion-based hydrogels could be recommended as proper vehicles for the derivative of phenylalanine.

In this study semisolid formulations containing AcYPFF (N-acetyl-Tyr-Pro-Phe-Phe-NH 2 ) tetrapeptide were obtained and characterized in terms of rheology, stability by multiple light scattering and particle size distribution by laser diffraction. Additionally, the release studies of tetrapeptide from formulations obtained were performed. The influence of different factors such as semisolid and membrane type on tetrapeptide release rate was examined. The release experiments of tetrapeptide modified with palmitoyl group (PalmYPFF) were also carried out. The results proved that formulation type and its rheological properties strongly determined the permeation process of the tetrapeptide. The fastest release of tetrapeptide was observed from hydrogel that had the lowest viscosity. The kinetic data of tetrapeptide released from oil-in-water (o/w) and water-in-oil (w/o) emulsions prepared at elevated temperature showed good fit to the Higuchi equation, whereas when AcYPFF was released from oil-in-water (o/w) emulsion prepared with the addition of auto-emulsifier high linearity with Korsmeyer-Peppas model was observed. While when tetrapeptide was released from Hydrogel the most suitable model was the first-order kinetics. It was suggested that mechanism that led to the release of tetrapeptide from all formulations was non-Fickian diffusion transport. The presence of palmitoyl group changed the solubility of tetrapeptide both in formulation and receptor fluid and thus the release rate of active compound was modified.

The ordered mesoporous silicas SBA-15 and KIT-6, modified with lanthanum, have been for the first time applied in investigation of ibuprofen adsorption and release. The materials of hexagonal and regular structure were obtained by the hydrothermal method using a triblock copolymer Pluronic P123 as a template. The mesoporous silicas were impregnated with an aqueous solution of lanthanum(III) chloride in the amount necessary to obtain 1, 3 and 5wt.% La loading. The physicochemical properties of the modified silicas were characterised by X-ray diffraction, transmission electron microscopy, UV-Vis spectrophotometry and low-temperature nitrogen sorption. The results showed that lanthanum strongly determined structural as well as textural properties of the silicas. The samples of modified silica were checked for the ability to adsorb and release of ibuprofen. The storage capacity of the modified silicas obtained increased with increasing their average pore diameter and percentage content of lanthanum. The amount of ibuprofen adsorbed onto KIT-6 silica modified with La was higher than that adsorbed onto SBA-15 materials. The high coverage of lanthanum on the surface of KIT-6 and SBA-15 solids was found to increase the amount of ibuprofen and the rate of its release., (Copyright © 2015 Elsevier B.V. All rights reserved.)

To be effective, probiotic bacteria must exhibit a number of functional characteristics, including the resistance to gastric acidity and the ability to adhere to the intestinal epithelium. In this study, we examined in vitro the viability of lactic acid bacteria (LAB) combination after exposure to low pH, and the adhesion of LAB to Caco-2 cells during coincubation of 9 bacterial strains. To test bacterial viability, 6 commercially available products were incubated in 0.1 N HCl at pH 1.2 for 60 min. The greatest growth inhibition was noted for the non-capsulated product containing the Lactobacillus rhamnosus strain (log reduction of CFU = 6.4), and the best survival observed for the product containing 9 bacterial strains, equipped with a modern capsule made according to the Multi-Resistant Encapsulation technology (log reduction of CFU = 0.1). In the adhesion experiment, the combination of 9 bacterial strains was added to 17-day-old Caco-2 cell culture for 90 min. The greatest efficiency of adhesion was observed for the inoculum containing 5.5x10(8) CFU/mL/9.6 cm(2) of Caco-2 and the dose of probiotic bacteria of 190 cells per one Caco-2 cell. As a result, approximately 157 bacterial cells adhered to one Caco-2 cell. The results indicate that the combination of 9 bacterial strains in the examined product is characterized as highly adhesive.

Sulforaphane (SFN) is an isothiocyanate that is naturally present in cruciferous vegetables, with high concentration in broccoli. The results of the most recent studies indicate multi-targeted sulforaphane actions which may contribute to prevention and therapy of cancer. Protective properties of sulforaphane have been observed in every stage of carcinogenesis. The mechanism of protection against the initiation of carcinogenesis by SFN includes modulation of phase I and II xenobiotic-metabolizing enzymes, as well as direct blocking of specific binding sites of carcinogens with the DNA molecule. As a result, sulforaphane inhibits DNA adduct formation, thus reducing the risk of mutations. Further sulforaphane activity is targeted at cancer cells and prevents their expansion due to regulation of proliferation and induction of differentiation or apoptosis. In vitro studies using various types of cancer cells have revealed the ability of SFN to arrest the cell cycle, particularly in G2/M, while SFN at higher concentration is shown to activate apoptotic pathways. The possible SFN anticancer effect in the progression stage of carcinogenesis has been proved by only a few studies, which provide evidence for its antiangiogenic and antimetastatic influence. Additionally, SFN exhibits anti-inflammatory and antibacterial effects relevant to cancer prevention. Apart from the biological activity of SFN, this review also focuses on its bioavailability and tissue distribution as well as individuals' genetic predispositions as significant factors influencing the potential efficiency of chemoprevention using this compound.

This review discusses the preventive and therapeutic potential of natural dietary compounds against colorectal cancer. The chemopreventive properties of many natural food matrices and purified bioactive compounds have been evaluated. Prominent among the dietary constituents that are the focus of interest in colorectal cancer chemoprevention are dietary fiber, probiotics and prebiotics, methionine and folate, vitamins D and E, calcium and selenium, anthocyanins, procyanidins, phytoestrogens, isothiocyanates, epigallocatechin gallate, curcumin, and resveratrol. Laboratory studies provide strong evidence for the antitumor potential of these dietary agents. The mechanisms of their chemopreventive action are associated with, for example, the modulation of gene expression involved in the regulation of cell proliferation, differentiation, and apoptosis and the suppression of metastasis and angiogenesis. The anti-carcinogenic properties of these food compounds are also related to inhibition of many inflammatory agents, including the expression of cyclooxygenase-2. In vitro and animal studies showed that most of them can protect against various carcinogens mediating colon cancer and suggest that they can also sensitize tumors to chemotherapy and radiation. Although experimental studies have clearly demonstrated their anticancer activity, not many clinical trials have provided satisfying results, not only because of the lack of efficiency of the chemopreventive agents, but also due to the lack of precise biomarkers monitoring their effects on colon cancer. Despite the lack of strong evidence for the anticancer potential of natural food compounds, clinicians have high hopes for using these factors in colon cancer chemoprevention and decreasing the incidence of this common malignancy in the future.

Hypertension accelerates the deterioration of the function of transplanted kidney. Aggressive control of blood pressure is recommended in post-transplant period when maintenance levels of the immunosuppressive drugs are achieved. The aim of this study was to compare the transplanted kidney function in two groups of the hypertensive patients matched for age, sex, HLA-mismatches, early post-transplant course, standard triple immunosuppression and hypotensive therapy during 3 years of follow-up. The mean through-levels of cyclosporine A in whole blood were similar in both groups and did not exceed 185 ng/ml. Group 1 consisted of 28 patients with satisfactory blood pressure (BP) control (arterial pressure below 160/90 mmHg) and group 2 consisted of 21 patients with unsatisfactory BP control. Slow but significant increase of the mean creatinine levels was observed in group 2 during 3 years of follow up, whereas in group 1 graft function remained stable. Cardiovascular events were observed only in group 2--stroke in one patient and death because of heart failure in one patient.