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Differential scanning calorimetry has been employed to study the thermal effects of vinblastine sulfate upon aqueous, single and multiple bilayer dispersions of 1,2-dipalmitoyl-3-sn-phosphatidylcholine (DPPC). The calorimetric results summarized to an increase in the gel to liquid–crystalline phase transition enthalpy and the abolishment of the Lβ′ (gel phase) to Pβ′ (ripple phase) pretransition for the uni- and multilamellar dispersions, as well as an increase in the transition temperature Tm and the transition cooperativity for single bilayer DPPC/vinblastine mixed vesicles, are consistent with an induced, partially interdigitated, gel phase. Computational analysis has been successfully applied to clarify the intermolecular effects and verify the feasibility of the proposed interdigitation for the vinblastine sulfate molecules and also for the ursodeoxycholic acid (UDCAH) and bromocylated taxanes, which have been shown to induce an interdigitated gel phase in DPPC bilayers. [Copyright &y& Elsevier]

The composition of the essential oil from the leaves of Cistus monspeliensis (Cistaceae) shows seasonal and diurnal variation. The essential oils were investigated by GC-FID and GC-MS. Labdanes which were identified for the first time in the essential oil of C. monspeliensis, are predominant in autumn and in winter and they were found in great amount with clerodanes in spring. Manoyl oxide, 3β-hydroxy-13-epi-manoyl oxide, 3β-acetoxy-13-epi-manoyl oxide and their isomers varied through the day and the year. The results obtained from GC-MS analysis of the oils were submitted to statistical analysis. [Copyright &y& Elsevier]

Abstract: Differential scanning calorimetry (DSC) has been employed to investigate the thermal changes caused by the anticancer alkaloid drug vinorelbine in dipalmytoylphosphatidylcholine (DPPC) bilayers. The total enthalpy change was increased by the presence of the drug molecule, indicating a partial interdigitation of the lipid alkyl chains. The presence of cholesterol in DPPC bilayers including vinorelbine induced an obstruction of the interdigitation, since cholesterol interrupts the upraise of enthalpy change. Vinorelbine''s interdigitation ability and stabilizing properties with the active site of the receptor have been compared with those of similar in structure amphipathic and bulky alkaloid vinblastine. The obtained results may in part explain their similar mechanism of action but different bioactivity. [Copyright &y& Elsevier]

Abstract: Liposomes composed of hexadecylphosphocholine/egg phosphatidylcholine/stearylamine (HePC/EPC/SA) 10:10:0.1, 10:10:0.5 and 10:10:1 (molar ratio) (1–3) were prepared and lyophilized. The liposomes were physicochemically characterized (size and ζ-potential) and they were found stable at 4 °C over a period of 4 weeks. In vitro, liposomes 1 and 2 were about twice more active than HePC against Leishmania donovani WT whereas liposomes 3 were about three times more active than HePC on HePC-resistant promastigotes. Although liposomes 1–3 were inactive on the in vitro intramacrophage amastigote model, the ability of the liposomes to accumulate within the liver where parasites are located justifies a further in vivo evaluation. We observed that liposome 1 was twice more active than HePC against Trypanosoma brucei brucei bloodstream forms maintained in vitro. In vivo results showed that liposomal HePC seemed to be less toxic than the free drug despite the absence of significant antitrypanosomal activity. [Copyright &y& Elsevier]

Abstract: Reactive oxygen species (ROS) are usually involved in two opposite procedures related to cancer: initiation, progression and metastasis of cancer, as well as in all non-surgical therapeutic approaches for cancer, including chemotherapy, radiotherapy and photodynamic therapy. This review is concentrated in new therapeutic strategies that take advantage of increased ROS in cancer cells to enhance therapeutic activity and selectivity. Novel biophotonic techniques for manipulation and characterization of drug delivery nanosystems in cancer therapy are discussed, including optical tweezers and atomic force microscopy. This review highlights how these techniques are playing a critical role in recent and future cancer fighting applications. We can conclude that Biophotonics and nanomedicine are the future for cancer biology and disease management, possessing unique potential for early detection, accurate diagnosis, dosimetry and personalized treatment of biomedical applications targeting cancer. [Copyright &y& Elsevier]

Abstract: Liposomes have been actively studied as models of cell membranes and are currently used as drug delivery systems of bioactive molecules. Liposome transformations that mimic cellular processes and are associated with their physicochemical properties have become field of interest the last decade. However, there has been little experimental work on controlled vesicle transformations by non-contact, optical handling methods. In this paper we present the use of line optical tweezers to observe liposome state transitions and transformations. Dynamic shape deformations were induced by line optical tweezers in giant stained liposomes leading to budding transition, fission and pearling creation. Under the controlled effect of line optical tweezers reversible liposome deformations were observed. The shear modulus μ of the membrane was inferred by measuring deformation of stained liposomes induced by the applied optical force. Further laser radiation caused irreversible shape deformations of liposomes, which were transformed from spherical to tubular vesicles. The ability of the selective manipulation of liposomes brings us closer to study their physicochemical properties which play a key role in cellular–liposome interactions, drug encapsulation and delivery efficiency. [Copyright &y& Elsevier]

Synopsis Preservatives are added to products for two reasons: first, to prevent microbial spoilage and therefore to prolong the shelf life of the product; second, to protect the consumer from a potential infection. Although chemical preservatives prevent microbial growth, their safety is questioned by a growing segment of consumers. Therefore, there is a considerable interest in the development of preservative-free or self-preserving cosmetics. In these formulations traditional/chemical preservatives have been replaced by other cosmetic ingredients with antimicrobial properties that are not legislated as preservatives according to the Annex VI of the Commission Directive 76/768/EEC and the amending directives (2003/15/EC, 2007/17/EC and 2007/22/EC). ‘Hurdle Technology’, a technology that has been used for the control of product safety in the food industry since 1970s, has also been applied for the production of self-preserving cosmetics. ‘Hurdle Technology’ is a term used to describe the intelligent combination of different preservation factors or hurdles to deteriorate the growth of microorganisms. Adherence to current good manufacturing practice, appropriate packaging, careful choice of the form of the emulsion, low water activity and low or high pH values are significant variables for the control of microbial growth in cosmetic formulations. This paper describes the application of the basic principles of ‘Hurdle Technology’ in the production of self-preserving cosmetics. Multifunctional antimicrobial ingredients and plant-derived essential oils and extracts that are used as alternative or natural preservatives and are not listed in Annex VI of the Cosmetic Directive are also reported. [ABSTRACT FROM AUTHOR]

Abstract: Ceramides are the most important intercellular lipids of the stratum corneum, regulating the barrier function of the skin and participating as second signal messenger in stress-induced apoptosis. The high lipophilicity of ceramides presents a pharmacological problem. In order to overcome this problem two lipophilic delivery systems were used for the incorporation of the ceramides: (1) nanoemulsions (NE) and (2) solid lipid nanoparticles (SLN). The influence of the incorporation of ceramides on the particle shape, size and Polydispersity Index was investigated by photon correlation spectroscopy (PCS) and scanning electron microscopy (SEM). The results showed that NE can incorporate larger amounts of ceramides than SLN (up to 23.2% and 5% of lipid matrix, respectively) without any significant alteration on the morphology of the dispersed particles. The incorporation of higher amounts of ceramides into SLN, leads to anisometric platelet-like formations that are known to be caused by the transition of triglycerides from α- to β-mesomorph. The results of this study can be useful for the design of appropriate delivery systems and for further pharmacological evaluations. [Copyright &y& Elsevier]

Abstract: Sclareol is a labdane-type diterpene that has demonstrated a significant cytotoxic activity against human leukemic cell lines. Here, we report the effect of sclareol against the human breast cancer cell lines MN1 and MDD2 derived from the parental cell line, MCF7. MN1 cells express functional p53, whereas MDD2 cells do not express p53. Flow cytometry analysis of the cell cycle indicated that sclareol was able to inhibit DNA synthesis induce arrest at the G0/1 phase of the cycle apoptosis independent of p53. Sclareol-induced apoptosis was further assessed by detection of fragmented DNA in the cells. Furthermore, sclareol enhanced the activity of known anticancer drugs, doxorubicin, etoposide and cisplatinum, against MDD2 breast cancer cell line. [Copyright &y& Elsevier]

Abstract: Sclareol (labd-14-ene-8,13-diol) is a highly water-insoluble molecule that belongs to the labdane type diterpenes and is characterized as a biologically active molecule, due to its cytotoxic and cytostatic effects against human leukemic cell lines. A superimposition study between sclareol and cholesterol, based on their corresponding hydrophobic and polar molecular segments calculated from their lipophilic profiles, revealed their spatial similarities. This structural similarity between the two molecules prompted us to compare their effects on the structure and stability of phospholipid dipalmitoylphosphatidylcholine (DPPC) membranes. Differential scanning calorimetry (DSC) was applied to compare the thermal changes caused by either cholesterol or sclareol when are incorporated in DPPC bilayers. The results showed that sclareol is incorporated into phospholipid model membranes and mimics the thermal effects of cholesterol especially at concentrations up to X sclareol =9.1mol%. These effects can be summarized as the abolition of pre-transition, lowering of the main phase transition and reduction of the enthalpy change (ΔH) of the gel to liquid-crystalline phase transition of DPPC bilayers. At concentrations X ≥16.7mol%, sclareol and cholesterol caused different heterogeneity in lipid bilayers or a reversible transition from a vesicular suspension to an extended peak bilayer network. This different fluidization, exerted by the two molecules at high concentration, may be related to their different stability and the z-average mean diameter of the liposomes they form. Small unilamellar vesicles, prepared by the thin film hydration method showed that DPPC bilayers containing a high concentration of sclareol in equimolar ratio sclareol:cholesterol were unstable, in contrast to the ones containing only cholesterol. [Copyright &y& Elsevier]

One promising class of antioxidant compounds is polyphenols, contained abundantly in pine bark extract(Pycnogenol®—pine bark extract). This medicinal extract is utilized for its anti-inflammatory properties. Its pharmacological action in skin depends on the kinetics of its absorption. In this study the dermal bioavailability of pine bark extract was investigated. Viable human skin, adapted on continuously perfused Franz cells, was applied with 5%(w/v) pine bark solution. Samples were taken at 0.5, 1, 2, 4, 6, 8, 10, and 12-hour intervals and analyzed for detection of pine bark extract constituents by high performance liquid chromatography(HPLC)(reversed phase column, isocratic conditions) coupled with an electrochemical detector(EC). Several constituents of pine bark extract such as gallic acid, protocatechuic acid, catechin, p-hydroxybenzoic acid, vanillin, and one unidentified constituent were detected. These findings indicate that pine bark extract is readily absorbed by human skin and can be used for topical application. [ABSTRACT FROM AUTHOR]

pp. 107–123 This work was partially presented at the 7th Joint Meeting of AFRP, ASP, GA, PSE and SIF, Athens, Greece, and at the XIIIth COSMODERM Joint Meeting of ESCAD and the Hellenic Society of Dermatology and Venerology, Athens, Greece. In recent years, there is a considerable interest in the development of preservative-free or self-preserving cosmetics. The aim of our work was to develop new cosmetic formulations by replacing chemical preservatives with ingredients with antimicrobial properties that are not legislated as preservatives according to Annex VI of Commission Directive 76/768/EEC. This paper describes the preservative efficacy of the well-known antimicrobial extracts of Lonicera caprifoleum and Lonicera japonica in combination with glyceryl caprylate and/or levulinic acid, p-anisic acid, and ethanol. We prepared a series of acidic (pH = 5.5) aqueous and O/W formulations, i.e., tonic lotion, shampoo, shower gel, conditioning cream, anticellulite cream, cleansing milk and peeling cream, containing (0.2% w/w) Lonicera extracts, alone in the case of tonic lotion and in combination with (1% w/w) glyceryl caprylate in the other products, and we performed challenge tests according to the European Pharmacopoeia procedures and criteria. Formulations such as shampoo, shower gel, and conditioning cream fulfilled criterion A, while tonic lotion, anticellulite cream, cleansing milk, and peeling cream fulfilled criterion B, in regard to contamination from A. niger. Furthermore, we evaluated the efficacy of the antimicrobial systems in two states of use: the intact product and after 3 weeks of consumer use. The results showed that A. niger was also detected during use by consumers in the products that satisfied only criterion B in challenge tests. The addition of antimicrobial fragrance ingredients such (≤0.3% w/w) levulinic acid or (0.1% w/w) p-anisic acid and/or (5% w/w) ethanol afforded products that met criterion A in challenge tests and were also microbiologically safe during use. The small quantity (5% w/w) of ethanol gave an important assistance in order to boost the self-preserving system and to produce stable and safe products. [ABSTRACT FROM AUTHOR]