Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
1.
Educ. med. super ; 36(2)jun. 2022. ilus, tab
Article in Spanish | LILACS, CUMED | ID: biblio-1404551

ABSTRACT

Introducción: Los mentefactos conceptuales como estrategia para el aprendizaje de la estadística inferencial desarrollan procesos cognitivos mediante diagramas, lo que estructura los temas conceptuales sobre la base de las operaciones intelectuales. Objetivo: Determinar el efecto de los mentefactos conceptuales como estrategia didáctica para el aprendizaje de Estadística Inferencial por estudiantes del IV ciclo de carrera profesional de psicología en la Universidad Peruana Los Andes. Métodos: Se ejecutaron una investigación experimental y un diseño pre experimental longitudinal con pre- y pos prueba. La muestra fue de 16 estudiantes del IV ciclo de la carrera profesional de psicología, matriculados en la asignatura de Estadística Inferencial. Se experimentaron los temas población y muestra y estimación estadística. Se aplicó una prueba objetiva de 10 ítems medidos en escala de razón. Los datos se procesaron mediante la estadística descriptiva y las pruebas de hipótesis. Resultados: En relación con el tema población y muestra, se demostró la significancia de la diferencia de medias en pre-y pos = 4,7 mayor que = 2,04 y α = 0,05; en la segunda fase el tema fue estimación estadística, en el cual la diferencia de medias en pre- y pos- resultaron significativos porque = 8,6 mayor que = 2,04, al aceptar la hipótesis alternativa. Conclusiones: Los mentefactos conceptuales como estrategia de aprendizaje de la Estadística Inferencial generó expectativas en estudiantes, quienes lograron su aprendizaje significativamente. Se reconoció la necesidad de aplicar sistemáticamente y con continuidad el modelo, dado que se obtiene mejor nivel de aprehensión de los conocimientos estadísticos(AU)


Introduction: Conceptual diagrams as a strategy for learning inferential statistics develop cognitive processes, structuring conceptual topics on the basis of intellectual operations. Objective: To determine the effect of conceptual diagrams as a didactic strategy for the learning of inferential statistics by students from the fourth cycle of the professional major of Psychology at Los Andes Peruvian University. Methods: An experimental research was carried out, together with a longitudinal, preexperimental, pre-test/post-test design. The sample consisted of sixteen students from the fourth cycle of the professional major in Psychology, enrolled in the Inferential Statistics subject. The topics about population and sample, as well as statistical estimation, were tested. An objective test of ten items measured on a ratio scale was applied. The data were processed using descriptive statistics and hypothesis testing. Results: Regarding the population and sample item, the significance of the difference in means between pre-test and post-test was demonstrated, being t cal =4.7, a value higher than t crit =2.04, and α=0.05. In the second phase, the topic was statistical estimation, for which the difference in means between pre-test and post-test resulted to be significant, because t cal =8.6, a value higher than t crit =2.04, by accepting the alternative hypothesis. Conclusions: Conceptual diagrams as a strategy for learning inferential statistics created expectations among students, who achieved their learning significantly. The need to apply the model systematically and continuously was recognized, given that a better level of apprehension of statistical knowledge is obtained(AU)


Subject(s)
Humans , Knowledge , Learning , Students , Statistical Inference
2.
Rev. colomb. ciencias quim. farm ; 51(1)ene.-abr. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1535832

ABSTRACT

Introducción: el estradiol es una hormona esteroide sexual femenina usada ampliamente como terapia hormonal que presenta una baja biodisponibilidad, debido a su baja solubilidad acuosa y a su alta hidrofobicidad, perteneciendo a la clase II del sistema de clasificación de biofarmacéutica. Objetivos: diseñar y caracterizar un sistema de entrega de fármacos autoemulsificable (SEDDS) para el fármaco estradiol por pruebas fisicoquímicas con el fin de obtener la relación óptima que permitiera mejorar su solubilidad acuosa, velocidad de disolución y potencialmente su biodisponibilidad. Método: estudios de solubilidad en diferentes solventes, diagramas de fases pseudoternarios constituidos por aceites, tensioactivos, cotensioactivos y agua permitieron reconocer las diferentes regiones de formación de SEDDS e identificar los porcentajes de excipientes que conducen a la formación de soluciones isotrópicas; las formulaciones resultantes fueron caracterizadas en tiempo de autoemulsificación, robustez a la dilución, punto de nube y perfil de disolución en capsula dura. Resultados: las formulaciones que contenían Capmul MCM®, Kolliphor® RH40 y Transcutol®, tuvieron un tiempo de autoemulsificación de aproximadamente 1 min; fueron estables en tres distintos pH (1,2; 4,5 y 7,2), en diferentes volúmenes de dilución, exhibiendo una apariencia transparente, ligeramente azulada, sin precipitados, o separación de fases, puntos de nube mayores en comparación de las formulaciones que contenían Gelucire® 44/14. Conclusiones: las estrategias de caracterización empleadas en el desarrollo de esta investigación demostraron ser eficientes para la selección adecuada de excipientes y su proporción óptima para el diseño eficaz de un sistema de entrega de fármaco autoemulsificable (SEDDS).


SUMMARY Introduction: Estradiol is a female sex steroid hormone widely used as hormonal therapy that has low bioavailability, due to its low aqueous solubility and high hydro-phobicity, belonging to class II of the Biopharmaceutical Classification System. Aim: To design and characterize a self-emulsifying drug delivery system (SEDDS) for the drug estradiol by physicochemical tests to obtain the most optimal ratio that would improve its aqueous solubility, dissolution rate, and potentially its bioavailability. Method: Solubility studies in different solvents; pseudo ternary phase diagrams made up of oils, surfactants, co-surfactants, and water, allowed to recognize the different regions of SEDDS formation and identify the percentages of excipients that lead to the formation of isotropic solutions; The resulting formulations were characterized in autoemulsification time, robustness to dilution, cloud point and dissolution profile in a hard capsule. Results: The formulations containing Capmul MCM®, Kolliphor® RH40, and Transcutol®, had an autoemulsification time of approximately 1 minute; were stable at three different pHs (1.2, 4.5 and 7.2), at different dilution volumes, exhibiting a transparent, slightly bluish appearance, without precipitates, or phase separation, higher cloud points compared to the formulations containing Gelucire® 44/14. Conclusions: The characterization strategies used in the development of this research proved to be efficient for the adequate selection of excipients and their optimal ratio for the effective design of a self-emulsifying drug delivery system (SEDDS).


Introdução: o estradiol é um hormônio esteroide sexual feminino amplamente utilizado como terapia hormonal que apresenta baixa biodisponibilidade devido à sua baixa solubilidade aquosa e alta hidrofobicidade, pertencente à classe II do sistema de classificação biofarmacêutica. Objetivos: projetar e caracterizar um sistema de liberação de drogas autoemulsificante (SEDDS) para o fármaco estradiol por meio de testes físico-químicos a fim de obter a proporção ideal que melhore sua solubilidade aquosa, taxa de dissolução e potencialmente sua biodisponibilidade. Método: estudos de solubilidade em diferentes solventes, diagramas de fases pseudoternários compostos por óleos, tensoativos, cotensoativos e água permitiram reconhecer as diferentes regiões de formação de SEDDS e identificar as porcentagens de excipientes que levam à formação de soluções isotrópicas; as formulações resultantes foram caracterizadas quanto ao tempo de autoemulsificação, robustez à diluição, ponto de turvação e perfil de dissolução da cápsula dura. Resultados: as formulações contendo Capmul MCM®, Kolliphor® RH40 e Transcutol®, tiveram um tempo de autoemulsificação de aproximadamente 1 min; foram estáveis em três diferentes pH's (1,2; 4,5 e 7,2), em diferentes volumes de diluição, apresentando aspecto transparente, levemente azulado, sem precipitados ou separação de fases, pontos de turvação mais elevados em relação às formulações contendo Gelucire® 44/14. Conclusões: as estratégias de caracterização utilizadas no desenvolvimento desta pesquisa mostraram-se eficientes para a seleção adequada de excipientes e sua proporção ideal para o desenho eficaz de um sistema de liberação de fármacos autoemulsificante (SEDDS).

3.
Ciênc. rural (Online) ; 51(3): e20200347, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1153867

ABSTRACT

ABSTRACT: The objective of this study was to design two diagrammatic scales for the evaluation of black node disease (Stagonosporopsis hortensis and Boeremia spp.) in common bean (Phaseolus vulgaris L.). The developed scales corresponded to logarithmic intervals (SADL) of seven levels and equal intervals (SADE) of nine levels. These scales were compared to the scale developed by the International Center for Tropical Agriculture (CIAT), which corresponds to a descriptive scale (NoSAD). In the scale validation the accuracy, precision, and concordance of repeatability were determined using Lin's concordance correlation coefficient, whereas inter-rater reproducibility was determined by the overall concordance correlation coefficient (OCCC). It was observed that with the use of the proposed scales, reproducibility and repeatability were significantly improved for inexperienced raters, and reproducibility was improved in the case of experienced raters. Thus, the designed standard area diagrams with equal and logarithmic intervals are a useful tool for estimating severity under field and experimental conditions as part of the study of this patho-system.


RESUMO: O objetivo deste estudo foi delinear duas escalas diagramáticas para avaliação da doença do nó preto (Stagonosporopsis hortensis e Boeremia spp.) em feijoeiro (Phaseolus vulgaris L.). As escalas desenvolvidas corresponderam a intervalos logarítmicos (SADL) de sete níveis e intervalos iguais (SADE) de nove níveis. Essas escalas foram comparadas com a escala desenvolvida pelo Centro Internacional de Agricultura Tropical (CIAT), que corresponde a uma escala descritiva (NoSAD). Na validação da escala, a exatidão, precisão e concordância da repetibilidade foram determinadas usando o coeficiente de correlação de concordância de Lin, enquanto a reprodutibilidade entre avaliadores foi determinada pelo coeficiente de correlação de concordância geral (OCCC). Observou-se que, com o uso das escalas propostas, a reprodutibilidade e a repetibilidade foram significativamente melhoradas para os avaliadores inexperientes, e a reprodutibilidade foi melhorada no caso dos avaliadores experientes. Assim, as escalas diagramáticas projetadas são uma ferramenta útil para estimar a severidade em condições experimentais e de campo como parte do estudo desse sistema patológico.

4.
China Pharmacy ; (12): 1655-1660, 2019.
Article in Chinese | WPRIM | ID: wpr-817116

ABSTRACT

OBJECTIVE: To establish content determination method of Triptolide-glycyrrhetic acid compound microemulsion, optimize the formula and investigate its physicochemical properties and release rate in vitro. METHODS: The content of Triptolide- glycyrrhetic acid compound microemulsion was determined by UPLC. The determination was performed on ACQUITY UPLC BEH C18 column with mobile phase consisted of 0.1% formic acid aqueous solution-acetonitrile (gradient elution) at the flow rate of 0.4 mL/min. The column temperature was 40 ℃. The detection wavelength was set at 218 nm, and sample size was 5 μL. Pseudo-ternary phase diagrams were drawn by water titration method. Using oil phase, surfactants and co-surfactants as index, the formula was optimized, and in intro release characteristics was investigated by in vitro release test. RESULTS: The linear range of triptolide and glycyrrhetinic acid were 1-40 μg/mL(r=0.999 7) and 10-400 μg/mL(r=0.999 8), respectively. The limits of quantitation were 0.5 and 0.8 μg/mL; the limits of detection were 0.1 and 0.2 μg/mL. RSDs of precision, stability and reproducibility tests were all less than 2%. Average recoveries were 100.32%-101.15% (RSD=0.36%, n=6), 99.78%-101.42% (RSD=0.59%,n=6). The optimal formula included that medium chain triglyceride as oil phase, polyethylene glycol hydroxy stearate as surfactants, ethanol as co-surfactants, water as water phase, the proportion of them was 8 ∶  28 ∶ 14 ∶ 50. The obtained microemulsion was O/W type, being transparent and clear, with average diameter, average polydispersity index and average viscosity of (62.38±3.44) nm, 0.096±0.001 and (26.84±1.10) mPa·S. Within 24 h, cumulative release rates of triptolide and glycyrrhetinic acid in obtained microemulsion were 99.8% and 99.7% (in PBS pH 2.0), 99.3% and 99.4% (in PBS pH 7.4), 98.9% and 98.4% (in PBS pH 9.0), respectively. Triptolide and glycyrrhetinic acid released faster in the single microemulsion than in the compound microemulsion. CONCLUSIONS: Established content determination method is simple and stable. The optimized formula is stable and feasible. Obtained iriptolide-glycyrrhetinic acid compound microemulsion show better sustained-release effect than sigle microemulsion.

5.
Chinese Traditional and Herbal Drugs ; (24): 2319-2324, 2019.
Article in Chinese | WPRIM | ID: wpr-851119

ABSTRACT

Objective :To fabricate resveratrol nanoemulsions and probe their pharmacokinetics profiles in rats in vivo. Methods The nanoemulsions of resveratrol were tailored by using aethylis oleas as the oil phase, Cremophor RH40 as emulsifiers, absolute alcohol as co-emulsifiers, respectively. The formulation was optimized by pseudo-ternary phase diagrams and their physicochemical properties of nanoemulsions were characterized by particle size distribution, transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FTIR). The pharmacokinetics experiments were also performed in rats after gavage and the plasm concentration of resveratrol were determined by HPLC as well as the profiles of pharmacokinetic parameters were obtained by Drug and Statistics (DAS) software. Results: The formula of nanoemulsions were as follows: the ratio of resveratrol-aethylis oleas-mixture surfactant- distilled water was 1:10:24:65. The average particle size diameters of prepared resveratrol nanoemulsions were about 40 nm and the droplets of nanoemulsions were in spherical shape observed by TEM. The results of IR disclosed that the active trans-resveratrol presented in the oil droplet of the nanoemulsions. Compared with resveratrol suspensions, the bioavailability of resveratrol nanoemulsions was increased 1.45-fold, and Cmax reached to 1.93-fold. Conclusion : These results indicated that nanoemulsions may be a promising tool for the delivery of resveratrol.

6.
Rev. lasallista investig ; 15(2): 315-326, jul.-dic. 2018. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1094001

ABSTRACT

Resumen Introducción: El empleo de asfaltos modificados con polímeros en la construcción de obras viales es una práctica frecuente a nivel internacional pero limitada aún en Ecuador. Sin embargo, ante la poca durabilidad de nuestros pavimentos asfálticos, mayormente causada por agrietamientos prematuros de fatiga o bloques, el potencial de estos productos debe ser considerado. Objetivo: Evaluar el comportamiento del asfalto procedente de la Refinería de Esmeraldas al mezclarse con tres tipos de polímeros, mediante las pruebas exigidas para la clasificación por viscosidad y por grados de desempeño Superpave, incluyendo un análisis reológico empleando diagramas de Black. Materiales y métodos: Los polímeros empleados fueron: SBS, Elvaloy y caucho de llantas, dosificados para cumplir ciertas exigencias de calidad determinadas por métodos experimentales, según las normativas ASTM. Resultados: Como principales resultados se obtuvo que al modificar el asfalto PG 64-28 con los distintos polímeros todos incrementaron el grado alto de temperatura a 76, manteniéndose el grado bajo en los modificados con Elvaloy y caucho en -28, mientras que para el SBS aumentó a -22. En relación a las temperaturas intermedias, la temperatura crítica a la fatiga no tuvo mayor variación al emplear los diferentes modificadores. Esta situación fue corroborada con los diagramas de Black. Conclusiones: Tratar de solucionar el mal comportamiento del asfalto ecuatoriano ante el agrietamiento mediante su mezcla con los polímeros estudiados no sería la solución más efectiva, aunque es notoria la mejora del comportamiento ante las deformaciones plásticas.


Abstract Introduction: The use of modified asphalts with polymers in the construction of roads is a frequent practice at an international level but still limited in Ecuador. However, due to the short durability of our asphalt pavements, mainly caused by premature fatigue cracks or blocks, the potential of these products should be considered. Objective: Evaluate the behavior of the asphalt coming from the Esmeraldas Refinery when it is mixed with three commercial polymers, by means of the tests required for the classification of viscosity and by Superpave performance grades, including a rheological analysis using master curves and Black diagrams. Materials and methods: The polymers used were: SBS, Elvaloy and rubber tires, dosed to meet certain quality requirements determined by experimental methods, according to ASTM regulations. Results: As main results the high degree of temperature increased to 76 by modifying the PG 6428 asphalt with the different polymers, maintaining the low degree on those modified with Elvaloy and rubber in -28, while for the SBS it increased to -22. Regarding to intermediate temperatures, the critical temperature to fatigue didn't have much variation when the different modifiers were applied. This situation was corroborated with Black diagrams. Conclusions: Trying to solve the poor cracking performance of the Ecuadorian asphalt by mixing it with the polymers studied would not be the most effective solution, although the improvement of the performance to plastic deformations is notorious.


Resumo Introdução: O uso de asfalto modificado com polímeros na construção de obras viárias é uma prática frequente em nível internacional, mas ainda limitada no Equador. No entanto, dada a curta durabilidade de nossos pavimentos asfálticos, causada principalmente por rachaduras prematura de fadiga ou blocos, o potencial desses produtos deve ser considerado. Objetivo: Avaliar o comportamento do asfalto da refinaria de Esmeraldas quando misturado com três tipos de polímeros, por meio dos testes exigidos para a classificação por viscosidade e pelos graus de desempenho Superpave, incluindo uma análise reológica usando diagramas pretos. Materiais e métodos: Os polímeros utilizados foram: SBS, Elvaloy e pneus de borracha, dosados para atender a determinados requisitos de qualidade determinados por métodos experimentais, de acordo com as normas da ASTM. Resultados. Como principais resultados, foi obtido que, ao modificar o asfalto PG 64-28 com os diferentes polímeros, todos aumentaram o alto grau de temperatura para 76, mantendo o baixo grau naqueles modificados com Elvaloy e borracha em -28, enquanto para o SBS aumentou para -22. Em relação às temperaturas intermediárias, a temperatura crítica à fadiga não apresentou muita variação ao utilizar os diferentes modificadores. Esta situação foi corroborada com os diagramas de Black. Conclusões: Tentar resolver o mau comportamento do asfalto produzido na Refinaria de Esmeraldas antes de partir pela fadiga, misturando-o com os polímeros estudados, não é a solução mais eficaz, embora seja notório a melhora do comportamento diante das deformações plásticas.

7.
Braz. J. Pharm. Sci. (Online) ; 54(1): e17232, 2018. tab, graf
Article in English | LILACS | ID: biblio-951908

ABSTRACT

The purpose of the study was to combine the advantages of self-nanoemulsifying drug delivery systems and tablets as a conventional dosage form. Self-nanoemulsifying drug delivery system (SNEDDS) was prepared to enhance the solubility and thus oral bioavailability of sertraline. Aqueous titration method was used to prepare the liquid SNEDDS; ternary phase diagrams were constructed and based on smaller droplet size (24.8 nm), minimum viscosity (153.63 cP) and polydispersity index (0.182), higher percentage transmittance (95%) and in vitro drug release (97%), an optimum system was designated. Liquid SNEDDS was transformed into free-flowing powder by solid adsorption technique followed by compression into tablets. In vitro release of sertraline from liquid and solid SNEDDS was found to be highly significant compared to plain sertraline (p<0.01). Pharmacokinetic studies after oral administration of liquid and solid SNEDDS in rats showed about 6-and 5-fold increased absorption of sertraline compared to the aqueous suspension of sertraline. These studies demonstrate that the solid SNEDDS are promising strategies for successful delivery of poorly water-soluble drug like sertraline


Subject(s)
Tablets/analysis , Biological Availability , Sertraline/pharmacology , Solubility , Administration, Oral , Emulsifying Agents
8.
Journal of China Pharmaceutical University ; (6): 688-693, 2016.
Article in Chinese | WPRIM | ID: wpr-811883

ABSTRACT

@#The purpose of this study was to prepare dabigatran etexilate nanoemulsion to improve bioavailability of dabigatran etexilate, a poorly water-soluble drug. The physicochemical properties and the stability of dabigatran etexilate nanoemulsion were investigated. Equilibrium solubility of dabigatran etexilate in commonly used oil materials for nanoemulsion were determined for selection. Then, surfactant and co-surfactant were chosen based upon the plooted pseudo-ternary diagrams. The formulation and preparation process were further optimized with orthogonal design. As a result, the dabigatran etexilate nanoemulsion was formulated based on the system consisting of Oil Acid/Labrafac Lipophile WL1394/Cremophor RH40/Transcutol P/H2O. The dabigatran etexilate nanoemulsion was found to have a mean diameter of(57. 5±0. 2)nm, Zeta potential of -(20. 9±1. 4)mV, and the drug encapsulation efficiency of(85. 2±1. 0)%. Besides, the droplet size, stability constant and drug content of the nanoemulsion was found to have no significant changes in at least 3 months under room temperature. In conclusion, the uniform and stable dabigatran etexilate nanoemulsion with a clear and translucent appearance was obtained after the optimization of formulation and preparation process. Thus nanoemulsion could be a promising way for the improvement of bioavailability of dabigatran etexilate and other poorly water-soluble drugs.

9.
Journal of China Pharmaceutical University ; (6): 581-586, 2016.
Article in Chinese | WPRIM | ID: wpr-811865

ABSTRACT

@#The aim of the study was to investigate the effect of oleic acid(OA)and isosorbide mononitrate(ISMN)on the phase diagrams of glyceryl monooleate(GMO)liquid crystalline systems and release of ISMN from them. Liquid crystalline systems of GMO/H2O, GMO/H2O/ISMN and GMO/H2O/OA were prepared and their phase diagrams were plotted. Investigation of water absorption of GMO and ISMN release profiles shown that the release mechanism of ISMN was diffusion-controlled. Increased drug loading accelerated the release rate. However, the increased loading of OA decreased ISMN release. The result could offer practical basis for drug loading and the selection of additives in GMO liquid crystalline system.

10.
Journal of China Pharmaceutical University ; (6): 437-441, 2016.
Article in Chinese | WPRIM | ID: wpr-811842

ABSTRACT

@#The purpose of this study was to investigate the formation thermodynamics of baicalein(BE)-nicotinamide(NCT)cocrystals in three solvents including ethyl acetate, acetone and trichloromethane. The solubilities of BE, NCT and BE-NCT in the above solvents at 25 °C were measured. Ternary phase diagrams(TPDs)of the BE-NCT-solvent systems were established. The non-linear fitting equation according to 1 ∶1 complexation mechanism of BE-NCT cocrystals demonstrated a good correlation between calculated and experiment data. ΔG0< 0 suggested that BE-NCT cocrystal formation was a spontaneous process. Among the organic solvents studied, the absolute value of ΔG0 in trichloromethane was significantly lower than that in the other two solvents. In addition, the cocrystallization zone in trichloromethane was far away from stoichiometric line. This study provides a theoretical foundation for solvent selection and preparation-condition optimization of BE-NCT cocrystals.

11.
Br J Med Med Res ; 2015; 10(4): 1-9
Article in English | IMSEAR | ID: sea-181733

ABSTRACT

Using causal diagrams and an axiomatization of causality, we examined the well-known claim that conditioning on confounders (“adjustment” for confounders) is sufficient to remove confounding bias. We show that this advice is poorly stated and is incomplete. To remove confounding bias, it is necessary to condition on three types of variables, none of which is a confounder. Conditioning on one of them, however, leads to an interesting form of colliding bias, which in turn, can be removed by conditioning on two other types of variables.

12.
World Science and Technology-Modernization of Traditional Chinese Medicine ; (12): 712-718, 2015.
Article in Chinese | WPRIM | ID: wpr-463971

ABSTRACT

The self-microemulsion formulation of potassium dehydroandrographolidi succinas (PDS) has been optimized and the performance in vitro has been evaluated preliminary. Kinds of prescription accessories were screened by solubility based on the emulsifying result and efficiency, particle size of emulsions. The optimal formulation composition and compatibility proportion were determined by orthogonal design and pseudo-ternary phase diagrams. The appearance, particle size, Zeta potential and stability of this formulation were also investigated. The optimized prescription of PDS was 10% MCT, 40% Tween-20 and 50% glycerol. It can spontaneously form a transparent pale blue opalescent emulsion with emulsification time 31.27 s, particle size 37.1 nm, Zata potential -17.4 mV and good stability.

13.
Journal of China Pharmaceutical University ; (6): 194-200, 2015.
Article in Chinese | WPRIM | ID: wpr-811933

ABSTRACT

@#The aim of this study was to investigate the effect of polymers on the formation thermodynamics of adefovir dipifoxil(AD)-saccharin(SAC)cocrystal. In the absence and presence of polymers such as polyethylene glycol, ethyl cellulose, polyvinylpyrrolidone and Eudragit E100, solubilities of AD and SAC in ethanol solution containing different concentrations of SAC at variable temperatures were determined by high-performance liquid chromatography(HPLC). Appropriate mathematical model for the description of the influence of polymers and temperature on the solubility of AD-SAC cocrystal was established. The ternary phase diagrams were set up using the assayed solubilities data, and they were used to predict changes of cocrystals solubility and product yield. Addition of polymers resulted in increased solubility of AD-SAC cocrystal, decreased complexation constants(K11), enhanced solubility products(Ksp), but there was a gradually decreased free energy change(ΔG0). The areas of homogeneous liquid phase and pure solid cocrystal in equilibrium with the liquid phase in ternary phase diagrams were also found to be larger. Therefore, although there was no change to the spontaneity of AD-SAC cocrystal formation, there existed retardation to cocrystal formation and reduction in product yield of pure cocrystal in the presence of polymers. Moreover, application of polymers could broaden the concentration range of AD and SAC solutions when solution crystallization was selected to prepare cocrystal.

14.
Braz. j. pharm. sci ; 50(3): 653-661, Jul-Sep/2014. tab, graf
Article in English | LILACS | ID: lil-728707

ABSTRACT

In this paper, nanostructured systems were developed, with the aid of ternary phase diagrams, from two surfactants, of differing degrees of lipophilicity (PPG-5-Ceteth-20 and the Oleth 10) and two oil phases (oleic acid and isopropyl myristate). It was observed that there were differences between the four resulting phase diagrams in the physical properties of the systems they represent. Thus, due to the capacity of Oleth 10 (as surfactant) and oleic acid (as the oil phase) to reduce interfacial tension, large regions of translucent systems were seen on the diagrams produced by them. By polarized light microscopy, it was possible to identify the isotropic and anisotropic properties of these systems, which were confirmed by small-angle X-ray scattering (SAXS) analysis. Furthermore, it was found that increasing the proportion of water in the formulations led to more highly organized structures, resulting in narrower and well defined SAXS peaks.


Neste trabalho, os sistemas nanoestruturados com diferentes níveis de organização foram obtidos através dos diagramas de fase ternários, utilizando tensoativos com de diferentes graus de lipofilicidade, o PPG-5-Ceteth-20 e o Oleth 10, e ácido oleico e miristato de isopropila como fases oleosas. Através dos diagramas foi possível observar diferenças significativas relacionadas com as características dos sistemas, devido à capacidade que o Oleth 10 (como tensoativo) e o ácido oleico (como fase oleosa) têm em diminuir a tensão interfacial, facilitando a formação de uma extensa região de sistemas transparentes. Através da microscopia de luz polarizada foi possível identificar as características isotrópicas e anisotrópicas dos sistemas, sendo posteriormente confirmadas pelas curvas de dispersão de raios X de pequeno ângulo (SAXS). Além disso, foi possível verificar que o aumento de água nas formulações proporcionou maior estruturação, permitindo a observação de picos mais estreitos e definidos nas curvas de SAXS.


Subject(s)
Oleic Acid/analysis , Nanostructures , Surface-Active Agents , Pharmaceutical Preparations
15.
Chinese Pharmaceutical Journal ; (24): 696-702, 2012.
Article in Chinese | WPRIM | ID: wpr-860743

ABSTRACT

OBJECTIVE: To investigate the O/W submicron emulsion injection formulation, and investigate its pharmacokinetics in the rat. METHODS: Pseudo-ternary phase diagrams were established using the water titration method. The effects of different surfactants, cosurfactants and Km values on the phase diagram were investigated, and the prescription of submicron emulsion formulation was optimized. Stability of coenzyme Q10 submicron emulsion was evaluated, and the pharmacokinetics in the rat after intravenous injection was study. RESULTS: Coenzyme Q10 submicron emulsion consisting of Poloxamer188/Lipoid S100/ethanol/PEG400/water has the lower viscosity, the smaller size and the higher encapsulation efficiency. An obvious sustained-release effect of coenzyme Q10 submicron emulsion was observed after iv injection in the pharmacokinetics experiment, and mean residence time is 6. 55 h. CONCLUSION: The optimized coenzyme Q10 submicron emulsion consumes smaller quantities of auxiliary materials and shows good stability. Moreover, it is easy to manufacture and convenient for clinical use. Copyright 2012 by the Chinese Pharmaceutical Association.

16.
Rev. bras. educ. méd ; 35(1): 122-131, jan.-mar. 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-586702

ABSTRACT

Este trabalho descreve e comenta uma experiência piloto de ensino de semiologia pediátrica em Unidades de Saúde da Família, através do uso de fluxogramas individualizados por idade, de acordo com a rotina do Ministério da Saúde para acompanhamento durante o primeiro ano de vida. O estudo foi realizado durante atendimento pediátrico inserido no módulo Piesc III para alunos do terceiro ano de Medicina da Universidade Estadual de Feira de Santana - Bahia (UEFS). Os fluxogramas foram aplicados em campo, mostrando-se efetivos para a sistematização das consultas de puericultura na etapa em que os estudantes se encontravam, reduzindo o estresse inicial, proporcionando maior segurança aos alunos e possibilitando anamneses mais extensas e esclarecedoras, com repercussão no aprendizado dos alunos e possibilidade de melhoria na qualidade da assistência às crianças e na oferta de dados em prontuários para pesquisa.


This paper describes and comments on a pilot teaching experience in clinical pediatrics in Family Health Units, using individualized flowcharts by age, according to the Brazilian Ministry of Health's guidelines for monitoring infants (0-12 months of age). The study was performed during pediatric care as part of training for third-year medical students at the State University in Feira de Santana, Bahia (UEFS). The flowcharts were applied in the field and proved effective for systematizing child care consultations at the students' respective stage of development, reducing the initial stress, providing greater security for students, and allowing more extensive and instructive case histories, with positive repercussions on the students' learning and the possibility for improved quality of care for children and recording of relevant data on patient charts, for use in future research.


Subject(s)
Humans , Education, Medical , Teaching/methods , Medical History Taking , Students, Medical
17.
Acta amaz ; 39(4)2009.
Article in Portuguese | LILACS-Express | LILACS, VETINDEX | ID: biblio-1455050

ABSTRACT

The present study evaluated the physical and chemical characteristics of the water of the rivers Solimões, Purus and their tributaries, collected in November of 2004 in the State of Amazonas between the cities of Manacapuru and Alvarães and Anamã and Pirarauara. Physical-chemical analyses (temperature, pH, electrical conductivity, turbidity, Ca2+, Na+, K+, Mg2+, HCO3-, SO4(2-), Cl-), and trace-elements (Li, B, Al, Sc, V, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Cd, Sb, Cs, Ba, Pb, La, Ce e U) and Sr isotopes were accomplished. The analyzed parameters and the chemical composition show that the waters of the rivers and tributaries of the central region of the Amazonia are chemically distinct between them. The white waters of Solimões are calcium-bicarbonate and of Purus are bicarbonates, and the respectives tributaries are sodium-potassium-bicarbonate and sodium-potassium-sulphate. This causes the white poorly acided waters to the neutrals and more conductives, while the black ones are less mineralized, more acids, mainly of Purus. The Ba, Sr, Cu, V e As in highest levels differentiate the Solimões white waters of the Purus`s waters, well as the tributaries of the first related to the second. This complex of caracteristics indicates that the Solimões as the Purus and their respectives tributaries are submitted to geological/ambiental distinct conditions. The influence of arrives in port of sediments of Andes is diluted at the currency of basin of the Solimões and it reflects on formation of fertile valleys Solimões and Purus. By another view, the crust rocks, represented by the Shields of the Guianas and Brasileiro both contribute, but in a reduced proportion.


Este trabalho discute as características físico-químicas das águas dos rios Solimões, Purus e seus afluentes, coletadas em novembro de 2004 no Estado do Amazonas, entre as cidades de Manacapuru-Alvarães e Anamã-Pirarauara. Foram realizadas análises físico-químicas (temperatura, pH, condutividade elétrica, turbidez, Ca2+, Na+, K+, Mg2+, HCO3-, SO4(2-), Cl-), de elementos-traço (Li, B, Al, Sc, V, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Cd, Sb, Cs, Ba, Pb, La, Ce e U) e isótopos de estrôncio. Os parâmetros analisados e a composição química mostram que as águas dos rios e igarapés da região central da Amazônia são quimicamente distintas entre si. As águas brancas do Solimões são cálcicas-bicarbonatadas e as do Purus bicarbonatadas, os respectivos afluentes são sódico-potássico-bicarbonatados e sódico-potássico-sulfatados. Isso acarreta águas brancas fracamente ácidas a neutras e mais condutivas, enquanto as pretas são menos mineralizadas, mais ácidas, especialmente as do Purus. O Ba, Sr, Cu, V e As mais elevados diferenciam as águas brancas do Solimões das do Purus, bem como os afluentes do primeiro em relação ao segundo. Esse conjunto de características indicam que tanto o Solimões, como o Purus e os respectivos afluentes, estão submetidos a condições geológicas/ambientais distintas. A influência do aporte de sedimentos dos Andes é diluída ao longo da bacia do Solimões e se reflete na formação das várzeas dos Solimões e Purus. Por outro lado as rochas crustais, representadas pelos escudos das Guianas e Brasileiro também contribuem, mas em menor proporção.

18.
Journal of Zhejiang Chinese Medical University ; (6)2006.
Article in Chinese | WPRIM | ID: wpr-559575

ABSTRACT

It introduces the model of Yinyang Taiji Eight Diagrams figure established by Pro.Xia Guicheng under acquired Eight Diagrams theory in Yi Classic,explains the essence of menstrual cycle evolution,hoping to guide the more effective diagnosis and treatment of gynecological incretory diseases,such as abnormal productive rhythm.

19.
Chinese Traditional and Herbal Drugs ; (24)1994.
Article in Chinese | WPRIM | ID: wpr-580775

ABSTRACT

Objective To optimize the formulation of self-microemulsifying drug delivery systems containing tanshinone ⅡA(tanshinone ⅡA-SMEDDS) and assess the quality of tanshinone ⅡA-SMEDDS. Methods Pseudoternary phase diagrams were used to choose the oil,emulsifier,co-emulsifier,and their proportion in the formulation on the basis of the ability to form emulsions and regions. Then the self-emulsifying time,droplet and morphology,size distribution,?-potential,stability,and other aspects of the quality were evaluated. Results The formulation of tanshinone ⅡA-SMEDDS was as follows:ethyl oleate-Labrasol-PEG 400=10%:45%:45%,drug loading ratio was 2.25 mg/g. The self-microemulsifying time of tanshinone ⅡA-SMEDDS in 0.1 mol/L hydrochloric acid solution was less than 1 min,the emulsion drops were spherical shape with average particle size of (84.9?2.1) nm and the average ?-potential (-24.0?1.15) mV (n=3). So tanshinone ⅡA-SMEDDS was stable. Conclusion In this paper,the tanshinone ⅡA-SMEDDS has a good self-emulsifying performance. It is expected to further stabilize the preparation of tanshinone ⅡA self-microemulsifying agents.

20.
Chinese Traditional and Herbal Drugs ; (24)1994.
Article in Chinese | WPRIM | ID: wpr-577325

ABSTRACT

Objective To study the preparation of Fructus perrillae oil nanoemulsion and its quality evaluation. Methods The formulations of Fructus Perrillae oil nanoemulsion were optimized by drawing the pseudoternary phase diagrams and investigating the form, viscosity, particle size distribution, stability, conductance, and refractiratio. Results The optimal formulation was composed of wheat oil and cremophor RH40, electron microscopy presented Fructus Perrillae oil nanoemulsion as small spherical drops, viscosity was (5.49?0.02)/mm2?s-1, conductance was 316/ms-1, refractiratio was (1.124?0.002 50), and mean diameter of particle was (50.3?1.1) nm.The average recovery determined by GC was 98.9%, its mean RSD was 0.88%. Conclusion The solubility and stability of Fructus Perrillae oil are promoted by nanoemulsion with better produncibility. It is a favorable medical matrix.

SELECTION OF CITATIONS
SEARCH DETAIL