36 research outputs found

    Usefulness of artificial membrane, strat-M®, in the assessment of drug permeation from complex vehicles in finite dose conditions

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    The ban on the use of animals in testing cosmetic products has led to the development of animal-free in vitro methods. Strat-M® is an artificial membrane engineered to mimic human skin and is recommended as a replacement for skin. However, its usefulness in the assessment of the permeation of cosmetics in in-use conditions remains unverified. No data have been published on its comparative performance with the membrane of choice, porcine skin. The comparative permeability characteristics of Strat-M® and porcine skin were investigated using Franz diffusion cells. Caffeine (CF) and rhododendrol (RD) in complex vehicles with varying concentrations of polyols were applied as finite and infinite doses. Good rank orders of permeation from finite dose experiments were observed for RD. High correlations were observed in RD permeation between Strat-M® and porcine skin under finite and infinite dose conditions, whereas only finite dose conditions for CF were associated with good correlations. Permeation from formulations with high polyol content and residual formulations was enhanced due to the disruption of the integrity of the Strat-M® barrier. The usefulness of Strat-M® in the assessment of dermal permeation may be limited to finite dose conditions and not applicable to infinite dose conditions or formulations applied in layers.11p. Article No.173 Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)

    La entomofauna triásica de la Cuenca Cuyana: nuevos registros y su importancia en el Gondwana

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    La Cuenca Cuyana, conformada por espesas secuencias sedimentarias del Triásico Medio a Superior comprende sistemas fluvio-lacustres bien desarrollados, que integran el Grupo Uspallata. La mayoría de sus unidades contienen ricas floras (Dicroidium) y faunas fósiles (tetrápodos, peces e invertebrados). Su paleobiodiversidad constituye uno de los más importantes registros de la vida continental desarrollada en el Gondwana. Los nuevos insectos proceden de dos áreas de la provincia de Mendoza: 1) sur del cerro Cacheuta (localidades Puesto Míguez, Quebrada del Durazno y Agua de las Avispas), en estratos de las formaciones Potrerillos y Cacheuta y, 2) norte del cerro Bayo de Potrerillos ("Quebrada del Puente"), en los niveles de la Formación Potrerillos. Estos registros comprenden impresiones de alas de hemípteros, blatópteros, odonatos y ortópteros; élitros y abdómenes de coléopteros; y dos ninfas asignadas a Plecoptera y Odonata. La nueva asociación está compuesta principalmente por insectos adultos alados (terrestres) y estadios ninfales (acuáticos). Hasta el presente, la Formación Los Rastros (Cuenca del Bermejo) presentaba la paleoentomofauna más abundante y diversa del Triásico argentino (230 ejemplares, 48 especies), seguida por las formaciones Potrerillos (30 ejemplares, 21 especies), Ischichuca (11 ejemplares, 11 especies), Llantenes (3 ejemplares, 3 especies), Cortaderita y Cacheuta (2 ejemplares, 2 especies). Los nuevos registros incrementan la biodiversidad conocida para la Cuenca Cuyana y para todo el Triásico de la Argentina ubicándolo a nivel regional, como el depósito más importante de este período, en cuanto a diversidad y abundancia de insectos fósiles (278 ejemplares, 11 órdenes, 27 familias, 87 especies). A nivel continental, se ubica como el tercero en importancia entre otros depósitos triásicos del Gondwana. La potencialidad de la mayoría de las unidades del Grupo Uspallata para el conocimiento de la paleoentomofauna del Triásico de América del Sur resulta tan significativa, como la de secuencias triásicas ya conocidas de Sudáfrica y Australia.Simposio III: Ecosistemas triásicos, su paleobiología y el contexto de recuperación de la gran extinciónFacultad de Ciencias Naturales y Muse

    Correlación del potencial óxido reducción y la población bacteriana durante el estudio de biolixiviación de sulfuros de cobre

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    The correlactionship of bacterial population and oxidation-reduction potential in the bioleaching of sulfuric minerals by bacterial strain of Aciditiobacilus Ferrooxidans isolated from acid mine effluent was studied. The solubilization of copper and gold release from a mineral with sulphides exceeding 80% was evaluated. The experimental variables were: Pulp density at 1, 2 and 6% (W/V), concentration of ferrous sulfate as part of the 9k medium of 0, 3, 6, 9 and 15 gr/L.; maintaining constant temperature and pH. The tests were carried out in three consecutive stages, starting with inoculum containing 7.05x107 Cell/mL and then the one obtained in each previous stage, observing the variation in the periods of adaptation and growth. In the first stage the maximum bacterial density reached in 24 days was 4.75x107 Cell/mL with 6 g/L of ferrous sulfate. In the second stage a maximum density of 6.30x107 Cell/mL was obtained without the addition of ferrous sulfate. In the third stage the bacterial density reached 4.51x107 Cell/mL, with exponential growth starts at approximately 13, 8 and 3 days, respectively. Bacterial strains are successfully adapted in different media containing varying amounts of iron and sulfuric minerals, regardless of iron sulfate as part of the bacterial substrat.Se estudio la correlación de las variables población bacteriana y potencial de óxido reducción (ORP) en la biolixiviación de minerales sulfurados mediante cepa bacteriana de Acidithiobacilus Ferrooxidans aisladas a partir de efluente ácido de mina, buscando la solubilización del cobre y la liberación del oro presente en un mineral con sulfuros superior a 80%. Las variables de experimentación fueron: La densidad de pulpa a 1, 2 y 6 % (W/V), concentración de sulfato ferroso como parte del medio 9k de 0, 3, 6, 9 y 15 gr/L; manteniendo constante la temperatura, agitación del medio y el pH. Los ensayos se realizaron en tres etapas consecutivas, iniciándose con inoculo conteniendo 7.05x107 Cel/mL y luego, la obtenida en cada etapa previa, observándose la variación en los periodos de adaptación y crecimiento. En la primera etapa la máxima población bacteriana alcanzada fue de 4.75x107 Cel/mL en 24 días con 6 g/L de sulfato ferroso. En la segunda etapa se obtuvo una máxima densidad de 6.30x107 Cel/mL sin la adición de sulfato ferroso. En la tercera etapa la densidad bacteriana alcanzada fue de 4.51x107 Cel/mL., con inicios de crecimiento exponencial aproximadamente a los 13, 8 y 3 días, respectivamente. Las cepas bacterianas fueron adaptadas satisfactoriamente en distintos medios conteniendo cantidades variadas de hierro y minerales sulfurados, dando mejores resultados sin la adición de sulfato ferroso

    Preparation, Characterization, Solubility, and Antioxidant Capacity of Ellagic Acid-Urea Complex

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    Ellagic acid (EA), a natural polyphenol found in berries, has high antioxidant capacity. This study aimed to improve EA solubility by complex formation with urea (UR) using solvent evaporation method and evaluate its solubility, antioxidant capacity, and physical properties. The solubility test (25 °C, 72 h) showed that the solubility of EVP (EA/UR = 1/1) was approximately two-fold higher than that of EA (7.13 µg/mL versus 3.99 µg/mL). Moreover, the IC50 values of EA and EVP (EA/UR = 1/1) (1.50 µg/mL and 1.30 µg/mL, respectively) showed higher antioxidant capacity of EVP than that of EA. DSC analysis revealed that the UR peak at 134 °C disappeared, and a new endothermic peak was observed at approximately 250 °C for EVP (EA/UR = 1/1). PXRD measurements showed that the characteristic peaks of EA at 2θ = 12.0° and 28.0° and of UR at 2θ = 22.0°, 24.3°, and 29.1° disappeared and that new peaks were identified at 2θ = 10.6°, 18.7°, and 26.8° for EVP (EA/UR = 1/1). According to 2D NOESY NMR spectroscopy, cross-peaks were observed between the -NH and -OH groups, suggesting intermolecular interactions between EA and UR. Therefore, complexation was confirmed in EA/UR = 1/1 prepared by solvent evaporation, suggesting that it contributed to the improvement in solubility and antioxidant capacity of EA.This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cite

    Preparation, Characterization, and In Vitro Evaluation of Inclusion Complexes Formed between S-Allylcysteine and Cyclodextrins

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    The present study prepared inclusion complexes of S-allylcysteine (SAC) and cyclodextrin (α, β, γ) by the freeze-drying (FD) method and verified the inclusion behavior of the solid dispersion. Also, the study investigated the effect of SAC/CD complex formation on liver tumor cells. Isothermal titration calorimetry (ITC) measurements confirmed the exothermic titration curve for SAC/αCD, suggesting a molar ratio of SAC/αCD = 1/1, but no exothermic/endothermic reaction was obtained for the SAC/βCD and SAC/γCD system. Powder X-ray diffraction (PXRD) results showed that the characteristic diffraction peaks of SAC and CDs disappeared in FD (SAC/αCD) and FD (SAC/γCD), indicated by a halo pattern. On the other hand, diffraction peaks originating from SAC and βCDs were observed in FD (SAC/βCD). Near-infrared (NIR) absorption spectroscopy results showed that CH and OH groups derived from SAC and OH groups derived from αCD and γCD cavity were shifted, suggesting complex formation due to intermolecular interactions occurring in SAC/αCD and SAC/γCD. Stability test results showed that the stability was maintained with FD (SAC/αCD) over FD (SAC/βCD) and FD (SAC/γCD). In 1H–1H of NOESY NMR measurement, FD (SAC/αCD) was confirmed to have a cross peak at the CH group of the alkene of SAC and the proton (H-3, -5, -6) in the αCD cavity. In FD (SAC/γCD), a cross peak was confirmed at the alkyl group on the carbonyl group side of SAC and the proton (H-3) in the cavity of γCD. From the above, it was suggested that the inclusion mode of SAC is different on FD (SAC/CDs). The results of the hepatocyte proliferation inhibition test using HepG2 cells showed that FD (SAC/βCD) inhibited cell proliferation. On the other hand, FD (SAC/αCD) and FD (SAC/γCD) did not show a significant decrease in the number of viable cells. These results suggest that the difference in the inclusion mode may contribute to the stability and cell proliferation inhibition

    Preparation and Characterization of a Hybrid Complex of Cyclodextrin-Based Metal—Organic Frameworks-1 and Ascorbic Acid Derivatives

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    Cyclodextrin-based metal–organic frameworks-1 (CD-MOF-1) prepared using potassium hydroxide, ethanol, and γ-cyclodextrin (γ-CD) has been reported as a new type of MOF for the development of pharmaceutical formulations. The present study aimed to investigate the physicochemical properties of ascorbic acid derivatives (L-ascorbyl 6-palmitate (ASCP); L-ascorbyl 2,6-palmitate (ASCDP)) complexed with CD-MOF-1 by a solvent evaporation method. Powder X-ray diffraction revealed that the crystal diffraction pattern of CD-MOF-1 changed from α-type to β-type when prepared by a solvent evaporation method. For ASCP/CD-MOF-1 = 1/2 and ASCDP/CD-MOF-1 = 1/4 evaporated samples, the crystal diffraction peaks derived from ASCP and ASCDP disappeared, indicating a β-like behavior. Differential scanning calorimetry results revealed that the endothermic peaks of evaporated samples (ASCP/CD-MOF-1 = 1/2 and ASCDP/CD-MOF-1 = 1/4) were not detected due to melting. Furthermore, intermolecular interactions were observed in the hydrogen bonds between the CH groups of the side chains of ASCP and ASCDP and the OH group of CD-MOF-1 in (ASCP/CD-MOF-1 = 1/2) and EVP (ASCDP/CD-MOF-1 = 1/4), based on the near-infrared absorption spectroscopy analysis. CD-MOF-1 did not form inclusion complexes with the lactone rings of ASCP and ASCDP, but with the lipophilic side chains. These results suggested that CD-MOF-1 may be useful in preparing novel drug carriers for ASCP and ASCDP.Article No.7309 This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cite

    Determination of sugars and amino acids in japanese wine using core-shell liquid chromatography tandem electrochemical detection

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    In this study, sugars (glucose, fructose, and sucrose) and amino acids in plum and yuzu wines were quantified with a new and simple method involving an electrochemical detector (ECD) and core-shell column [S-30/70=St (styrene)/DVB (divinylbenzene)-5TMDAH (tetramethyldiaminohexane)]. Analysis was conducted under the following conditions: A column temperature (40°C), flow rate (0.3 mL/min), injection volume (20 μL), and mobile phase (0.1 mol/L NaOH). Glucose, fructose, and sucrose had retention times of 14.68 min, 16.22 min, and 19.29 min, respectively, when measured using an ECD. When the sugar content was compared among the plum wines, plum wine A had the lowest sugar content. A comparison of the sugar content of the different types of yuzu showed that yuzu wine C had the lowest sugar content. In addition, plum wine C showed higher values of amino acid components (2.27 μmol/mL of alanine, 0.67 μmol/mL of GABA, and 5.28 μmol/mL of glutamic acid) compared with A and B. This straightforward LC technique is reliable in the determination of carbohydrates and amino acid contents in wine, useful criteria for consumers in selecting wines parallel to their ideal health outcomes

    Effect of layered application and finite dose conditions on the skin concentration and permeation of drugs

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    学位授与機関:城西大学 学位記番号:博甲第97号,学位の種別:博士(薬科学), 学位授与年月日: 令和2年(2020年)3月17日 (75p.)博士(薬科学)城西大
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