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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Relação estrutura-propriedades da amilopectina presente na solução do amido do tipo amidex 40003 e seus complexos metálicos

Peres, Gisele Louro January 2013 (has links)
O presente trabalho de tese desenvolveu uma metodologia analítica na obtenção e na produção de uma solução de amilopectina extraída da solubilização do Amidex 40003, amido geneticamente modificado contendo majoritariamente amilopectina, dissolvido na mistura dimetilsulfóxido (DMSO)/H2O (90/10% v/v), respectivamente. O objetivo foi produzir e caracterizar nanocomplexos de amilopectina com íons metálicos Cr3+, Fe3+, Cu2+, Ni2+, Co2+ e Pb2+ nas formas de sais de acetato, cloreto e nitrato, assim como, compreender as propriedades inorgânicas e físico-químicas (relação estrutura/propriedades) dos complexos formados, para futuras aplicações cosméticas. Foi realizado o monitoramento das características moleculares da solução de amilopectina durante a sua preparação sob ultrassom, em diferentes tempos e amplitudes, bem como em alguns complexos, através das técnicas de espectroscópia de espalhamento de luz (LS), viscosimetria, dentre outras. A redução da massa molecular da solução polimérica através do uso do ultrassom demonstrou que a metodologia desenvolvida é adequada para a redução e controle de tamanho da cadeia polimérica. O planejamento fatorial completo 23 foi realizado para a otimização das reações de complexação mostrando que o tempo de reação e a concentração são variáveis significativas. Além disso, as análises de pH, condutividade, infravermelho (FTIR), UV-Visível (UV-Vis), termogravimetria (TGA) e espalhamento de luz estático e dinâmico foram utilizados na confirmação dos complexos formados, bem como um estudo nas mudanças conformacionais ocorridas após a complexação com a solução de amilopectina. Os complexos com íons Cr3+ e Fe3+ possuem um rendimento reacional maior, comparado com os demais metais. O estudo reológico demonstrou a redução na viscosidade quando introduzidos os sais metálicos, devido ao empacotamento das cadeias poliméricas. Sendo que os sais de NO3- possuem uma estabilidade maior. O valor da viscosidade intrínseca encontrada foi de 1257 mL.g-1 para a solução de amilopectina e a concentração crítica (c*) da solução foi igual a 0,795 mg.mL-1. Foi verificado que o pH para as reações de complexação próximo de 5 é ideal para uma maior média de complexação. Em pH acima de 8, diminui o poder complexante do metal na solução. O uso da ferramenta estatística de separação por similaridade, i-PCA, proporcionou uma melhor compreensão do conjunto de dados, extraídos do FTIR. Através do estudo da relação estrutura-propriedades dos complexos metálicos com a amilopectina tratada em solução conclui-se que o polímero em solução encontra-se como uma esfera não homogênea e enovelada, sendo que após a complexação com íons metálicos a macromolécula modifica sua conformação em solução. Para todos os complexos formados ficou evidenciado um aumento do Rh, com exceção dos sais de Cr3+. Os resultados obtidos pelo gráfico de Berry mostram-se mais apropriado, pois a amilopectina possui elevadas ramificações, cujo as cadeias exteriores são cadeias flexíveis e não rígidas, o que facilita a complexação com os sais metálicos. Com o monitoramento, através da técnica do Espalhamento de luz estático de multiplas amostras (SMSLS) é evidenciado o aumento da massa molecular ao adicionar o sal. A nanopartícula de amilopectina desenvolvida é altamente estável e compatível com bases cosméticas. Estudos posteriores serão realizados para a aplicabilidade cosmetologia, como hidrogéis e emulsões oleosas. / The present work work developed an analytical method to obtain and produce a solution of extracted solubilization of amylopectin Amidex 40003, genetically modified starch containing mostly amylopectin dissolved in DMSO/H2O mixture (90/10 v / v%), respectively. The objective was to produce and characterize amylopectin nanocomplexes with Cr3 +, Fe3 +, Cu2 +, Ni2 +, Co2 + and Pb2 + metal ions in the form of acetate, chloride and nitrate salts, as well as understanding the properties of inorganic and physical-chemical properties (the structure / properties) of complexes formed for future cosmetic applications. The monitoring of molecular characteristics of amylopectin solution was conducted during its preparation under ultrasound at different times and amplitudes, as well as in some complexes, using such as light scattering spectroscopy (LS), viscosimetry, techniques. The reduction of the molecular weight of the polymer solution using ultrasound demonstrated that this methodology is suitable for the reduction and control of the size of the polymer chain. The 23 full factorial design was performed to optimize the complexation reactions showing that the reaction time and concentration are significant variables. In addition, pH, conductivity, infrared (FTIR) spectroscopy, UV-Visible (UV-Vis), thermogravimetry (TGA) and static and dynamic light scattering (techniques) were used for the confirmation of complexes formed, and a study in conformational changes occurred after complexation with the solution of amylopectin. Complexes with Cr3+ and Fe3+ have a higher reaction yield compared to the other metals. The rheological study demonstrated a reduction in viscosity when introducing metal salts due to the packing of polymer chains. Since NO3- salts have greater stability, the value of the intrinsic viscosity was found to be 1257 mL.g-1 solution to amylopectin and the critical concentration (c *) of the solution was equal to 0.795 mg.mL-1. It was found that the pH for complexation reactions around 5 is ideal for a higher average complexation. At pH above 8 decreases the complexing power of the metal in solution. The use of statistical tools separation similarity, i-PCA provided a better understanding of the data set extracted from FTIR. Through the study of the structure-properties of metal complexes in solution treated amylopectin concluded that the polymer is in solution as a sphere inhomogeneous and coiled, and after complexation with metal ions, the macromolecule alters its conformation in solution. For all complexes there was an evident increase of Rh, with the exception of Cr3 + salts. The results shown in the Berry plot were most suitable due to the high amylopectin branches whose outer chains are flexible and not rigid, which facilitates the complexation with metal salts. Using the technique of static light scattering of multiple samples (SMSLS) an increased molecular mass by adding salt is evident. The amylopectin nanoparticle developed is highly stable and compatible with cosmetic bases. Further studies will be performed to the applicability in cosmetology, such as hydrogels and oil emulsions.
12

Filtros Solares: determinação espectrofotométrica e cromatográfica / Sunscreens: spectrophotometric and chromatographic determination

Elizângela Abreu Dutra 29 November 2000 (has links)
Para minimizar os efeitos danosos a pele causados pelas radiações ultravioleta (UV), novos produtos cosméticos contendo filtros solares tem sido desenvolvidos e estão disponíveis no comércio. Consequentemente é necessário o desenvolvimento e validação de métodos analíticos para determinação quantitativa desses filtros solares em produtos cosméticos. O objetivo desta pesquisa foi a determinação quantitativa e simultânea dos filtros solares químicos, tais como, benzofenona-3, metoxicinamato de octila e salicilato de octila contidos em preparações cosméticas, por cromatografia líquida de alta eficiência (CLAE) e espectrofotometria no UV/visível. Paralelamente foi determinado o FPS para as amostras utilizando a espectrofotometria no uv/visível. A separação e determinação quantitativa pelo método cromatográfico foi realizada usando uma coluna LiChrospher® 100 RP-18 (5µm), fase móvel constituída de metanol-água (85:15, v/v), com vazão de 1,0mL/min e detecção no UV a 310nm. Os coeficientes de correlação e percentuais de recuperação para benzofenona-3, metoxicinamato de octila e salicilato de octila foram de 0,9999 e98,9%; 0,9995 e 99,9%;0,9998 e 98,9%, respectivamente. A média do desvio padrão relativo foi de 0,6%. A determinação espectrofotométrica só foi possível quando os filtros em estudo estão de forma isolada nas preparações cosméticas. O método espectrofotométrico foi validado a 287nm, 310nm e 306nm para benzofenona-3, metoxicinamato de octila e salicilato de octila, respectivamente; os coeficientes de correlação foram de 0,9998; 0,9999; 0,9998, respectivamente. O percentual de recuperação para a amostra comercial contendo apenas metoxicinamato de octila foi de 99,6%. A média do desvio padrão relativo foi de 0,5%. O Fator de Proteção Solar (FPS) determinado pelo método espectrofotométrico, para as preparações comerciais, não correspondeu aos mesmos valores rotulados. / In order to minimize the damaging effects to the skin caused by the ultraviolet (UV) radiation, several cosmetic products containing sunscreens has been developed and are available commercially. Consequently, it is necessary to develop and validate an analytical method for quantitative determination of sunscreen agents in cosmetic products. The aim of this research was to develop a high performance liquid chromatographic and a UV / visible spectrophotometric quantitative method for simultaneous determination of chemical sunscreens benzophenone-3, octyl methoxycinnamate and octyl salicylate contained in cosmetic product. At the same time, the Sun Protection Factor (SPF) was determined for the samples using UV / visible spectrophotometry. The separation and quantitative determination was achieved using a LiChrospher® 100 RP-18 (5µm) column, a mobile phase constituted of methanol-water (85: 15, v/v), a flow-rate of 1.0 mL/min and UV detection at 310nm. The correlation coefficient and percentage of recovery for benzophenone-3, octyl methoxycinnamate and octyl salicylate were 0.9999 and 99.05%; 0.9995 and 100.55%; 0.9998 and 98.05%, respectively. The average relative standard deviation (RSD) was 0.6%. The spectrophotometric determination was possible only when the sunscreens studied were in an isolated form, in cosmetic preparations. The spectrophotometric method was validated at 287nm, 310nm and 306nm for benzophenone-3, octyl methoxycinnamate and octyl salicylate, respectively. The correlation coefficients were 0.9998, 0.9999 and 0.9998, respectively. The percentage of recovery for commercial sample containing only octyl methoxycinnamate was 99.6%. The average relative standard deviation (RSO) was 0.5%. The Sun Protection Factor (SPF) determined by the spectrophotometric method, in the commercial preparations, did not corresponded to the labeled values.
13

高中職實習課程與教學之研究--以美容科為例

黃紹業 Unknown Date (has links)
本研究旨在探討高中職美容科實習課程與教學之現況,並根據研究結果與發現,探討可能原因,提出相關建議,以作為高中職美容科實習課程之參考。本研究首先透過文獻分析建立理論基礎,探究美容科實習課程內涵與實施方式,並輔以問卷調查蒐集實習課程教學現況,藉以達成本研究之目的。 本研究採取問卷調查法,抽取北部地區十九所設有美容科之高中職校,任教於美容科之教師共167位為樣本,以自編之「高中職美容科實習課程與教學問卷」進行調查,所得資料分別以描述分析、t考驗、單因子變異數分析、雪費事後比較等統計方法進行資料分析。研究結論如下: 一、美容科教師在實習課程教學上注重產學相關性以及就業之銜接。 二、美容科教師對學校設備與資源提供較為肯定,但對於實習計畫的擬定與實施較不認同。 三、美容科教師對實習課程的開設上,認為首要需考量就業市場、強化師資與注重師資的專業性。 四、美容科教師認為實習課程之實施應著重講解、示範與實作。 最後根據研究結果與結論,提出具體建議,以作為教育行政機關、學校、教師及未來研究的參考。 / The purpose of this study is to explore the status quo of the practical training program and teaching of Cosmetology Department in High School and Vocational High School. With the foundation of the research results and findings, several suggestions are made for the cosmetology departments of High Schools and Vocational High Schools. The Study was implemented with literature review and survey study. At first, theoretical foundation was established so as to know the connotation and mode of practice of practical training program. Secondly, survey study was applied to gather the information of current practical training program teaching, and attained the aim of this study. The study focused on 19 High Schools that with cosmetology department in the Northern Taiwan. Using the “Questionnaire on the Practical Training and Teaching of Cosmetology Department in High Schools and Vocational High Schools” compiled by the Researcher, the questionnaire survey was conducted to receive a total of 167 effective questionnaires from 167 teachers of cosmetology department. The data were analyzed through SPSS 10.0 for Windows software packages, further analyzed through descriptive analysis, t-test and one-way ANOVA for assumption and test. Those up to the significant research hypothesis were further taken into comparison through the Schefféé method to look into various divergences. The main findings of this study were as follows: 1. Practical training program teaching of cosmetology program should emphasize on meeting the enterprises’ need. 2. Most of the teachers of cosmetology departments were satisfied with the school equipments and resources, but felt less satisfied with the training program planning and policy. 3. Most of the cosmetology departments’ teachers approved that when set up a training program, the prior considerations should be: 1. job market, 2. teachers’ quality enhancement, 3. teachers’ specialty requirement. 4. Most of the cosmetology departments’ teachers believed that practical training program should lay particular stress on comprehension, demonstration and practice. Based on the findings of this study, proposals would be offered to the educational administration authorities, schools, school teachers as well as future researchers.
14

Segurança e eficácia antioxidante pré-clínica e clínica de etossomas contendo rutina  de orientação de uso cosmético / Preclinical and clinical safety and antioxidant efficacy of rutin-loaded ethosomes of cosmetic use guidance

Candido, Thalita Marcilio 18 October 2016 (has links)
Os cuidados com a pele abrangem gama de ações: cuidados com a exposição solar, alimentação balanceada, não tabagismo e alcoolismo e aplicação de produtos cosméticos, dentre outras. Sabe-se que subtâncias antioxidantes, endógenas e exógenas, auxiliam na manutenção do aspecto saudável e jovial da pele. A rutina, flavonoide pertencente à classe dos flavonóis, apresenta intensa atividade antioxidante, sendo empregada na indústria alimentícia, na prevenção ou tratamento da insuficiência venosa ou linfática e na prevenção aos danos causados pela radiação ultravioleta, por exemplo. Porém, a rutina possui taxa reduzida de permeação cutânea. O presente trabalho destinou-se a incorporar a rutina em etossomas, avaliando a segurança in vitro e in vivo, e a eficácia in vitro e ex vivo. As vesículas foram analisadas quanto ao tamanho de partícula, potencial zeta, taxa de encapsulação da rutina, atividade antirradicalar e potencial de irritação in vitro. As formulações foram avaliadas quanto ao valor de pH, características organolépticas, atividade antioxidante in vitro e ex vivo e permeação cutânea ex vivo. Os etossomas, com e sem rutina, foram obtidos por meio técnica de dispersão mecânica seguida de nova hidratação de filme, com partículas em dimensão nanométrica (369,5 e 247,0 nm, respectivamente). O potencial zeta para os etossomas sem rutina correspondeu à -39,3, enquanto que para aqueles com rutina foi -19,6. A rutina associada ao sistema etossomal foi igual a 80,1%. A rutina nas vesículas etossomais foi capaz de manter o potencial antirradicalar do flavonoide, verificado em ensaio in vitro. Os etossomas com rutina demonstraram-se seguros por meio dos ensaios in vitro e in vivo, sendo aplicados em ensaio posterior de permeação cutânea ex vivo, em voluntários. Foi observada taxa de permeação cutânea superior da rutina em etossomas em comparação com a rutina livre, assim, etossomas contendo rutina tornam-se um possível ingrediente ativo para adição em dermocosméticos destinados para uso contra o envelhecimento precoce. / Skin care covers a range of actions: limited sun exposure, a balanced diet, non smoking and non-alcoholism, and application of cosmetics. It is known that antioxidants, both endogenous and exogenous substances, assist in maintaining a healthy and youthful appearance of the skin. Rutin, a flavonoid belonging to the class of flavonols, has intense antioxidant activity and it is used in the food industry, in the prevention or treatment of venous or lymphatic insufficiency, and to prevent the damage caused by UV radiation. However, rutin has low skin permeation rate. This study was designed to incorporate rutin in ethosomes, evaluating their safety in vitro and in vivo, and efficacy in vitro and ex vivo, in order to assess the improvement of the skin permeation of the flavonoid. The ethosomes with and without rutin were obtained by a mechanical dispersion technique followed by a new lipid film hydration. The ethosomes were analyzed for particle size, zeta potential, encapsulation rate of rutin, antiradical activity and in vitro irritation potential. The formulations were evaluated for pH, organoleptic characteristics, antioxidant activity in vitro and ex vivo and ex vivo skin permeation. The association of rutin with ethosomal vesicles was able to mantain the antiradical potential of flavonoid. The ethosomes with rutin have shown to be safe through in vitro and in vivo safety assays, being applied in subsequent ex vivo tests to evaluate the skin permeation of rutin in human volunteers. A higher skin permeation rate was observed for rutin in ethosomes compared to the free rutin, thus rutin loaded ethosomes have potential as a compound in dermocosmetic formulations for premature aging.
15

Avaliação histológica do tecido adiposo da pele de ratas sob ação de cafeína e Cafeisilane® C / Histological evaluation of fatty tissue under the skin of rats caffeine action and Cafeisilane® C

Tano, Clara Tsugumi Nakamura 03 November 2003 (has links)
Hidrolipodistrofia ginóide é uma alteração genuína e loco-regional do panículo adiposo subcutâneo determinante do formato corporal característico da mulher. Várias substâncias ativas podem ser empregadas como anticelulíticos, sendo selecionado para esse trabalho a cafeína e o silício orgânico da cafeína (Cafeisilane® C). Foram desenvolvidas formulações cosméticas (9 emulsões empregando como base cera emulsionante não iônica e 3 géis utilizando polímero carboxivinílico e 1 gel a base de hidroxietilcelulose) contendo cafeína 4,0% p/p; cafeína e benzoato de sódio, ambos a 4,0% p/p e Cafeisilane® C 6,0% p/p e, as mesmas foram submetidas ao estudo de estabilidade acelerada nas seguintes condições: 4° C, ciclos alternados gela/degela (-10° C/45° C), 45° C, -10° C, 22° C e luz solar indireta. Das formulações avaliadas foram selecionadas uma emulsão não iônica e um gel de hidroxietilcelulose para o estudo \"in vivo\" em modelo animal, a fim de avaliar a ação lipolítica da cafeína e Cafeisilane® C. Após análise histológica do dorso depilado das ratas de linhagem Wistar, tanto a cafeína como o Cafeisilane® C apresentaram melhor resposta quando incorporados em emulsão não iônica, ocorrendo redução no diâmetro das células adiposas em 17% para a cafeína e 16% para o Cafeisilane® C. Nesta última preparação, também ocorreu redução de 32% no número de células adiposas. Da forma cosmética gel, apenas o que utilizou como base a hidroxietilcelulose com Cafeisilane® C promoveu redução de 26% no número de adipócitos quando comparado com o gel controle. / Gynoid hydrolipodystrophy is a genuine and regional alteration of the hypodermis, a subcutaneous tissue that determines the characteristic format of the female\'s body. Several active substances can be added in anticellulite cosmetics and in this research there were selected caffeine and siloxanetriol alginate caffeine (Cafeisilane® C). There were developed different cosmetic formulations (9 emulsions with nonionic emulsifying wax, 3 gels with carboxyvinilic polymer and 1 gel with hydroxyethyl cellulose) employing caffeine 4,0% w/w; caffeine and sodium benzoate, both 4,0% w/w, and Cafeisilane® C 6,0% w/w. Formulations above were submitted to the stress testing: 4° C, alternate freeze/thaw cycles (-10° C/45° C), 45° C, -10° C, 22° C and indirect sunlight, as the conditions. We selected one nonionic emulsion and the hydroxyethyl cellulose gel for the in vivo study in animal model for the evaluation of the lypolitic activity of caffeine and Cafeisilane® C. After histological analysis of Wistar\'s depilated back (female rats), as much caffeine as Cafeisilane® C resulted better answers when incorporated in nonionic emulsion, with diameter reduction of the fatty cells in 17% for caffeine and 16% for Cafeisilane® C. Within the Cafeisilane® C emulsion, reduction of 32% in the number of fatty cells occurred. Only hydroxyethyl cellulose gel with Cafeisilane® C promoted the reduction of 26% in the adipocytes numbers, when compared with the control gel.
16

Étude de la dynamique mitochondriale dans des cellules cutanées humaines : Mise en place de modèles pour des applications en cosmétologie / Mitochondrial dynamic in human skin cells : models development for cosmetic applications

Jugé, Romain 20 June 2016 (has links)
La peau est un épithélium spécialisé vital et fragile, qui évolue avec l’âge et est influencé par l’environnement, notamment les radiations solaires. Des données sont disponibles sur la réponse du réseau mitochondrial et le devenir des mitochondries endommagées en réponse à des stress chimiques et environnementaux dans plusieurs systèmes expérimentaux, mais ces processus restent peu étudiés dans les cellules cutanées. Dans ce contexte, le projet de thèse visait à analyser l’effet (i) de l’irradiation UVB sur la dynamique mitochondriale (en particulier la fragmentation des mitochondries) dans des kératinocytes primaires humains normaux, qui constituent la première ligne de défense contre les agressions externes ; (ii) d’un traitement par des poisons mitochondriaux sur les mitochondries contenues dans des kératinocytes ou des fibroblastes primaires humains normaux. Dans un premier axe de la thèse, nous avons mis au point une méthode originale (Mitoshape) basée sur l’imagerie confocale, permettant d’estimer à la fois qualitativement et quantitativement la morphologie du réseau mitochondrial dans des cellules vivantes après irradiation UVB. Grâce à cette technologie, nous avons pu montrer que les UVB induisaient une fragmentation du réseau mitochondrial dans les kératinocytes primaires, dont nous avons étudié les acteurs biochimiques. Dans un deuxième axe, nous avons montré que les poisons mitochondriaux avaient la capacité d’endommager les mitochondries dans des kératinocytes et des fibroblastes humains primaires et induisaient une autophagie générale sans toutefois exclure la présence d’une mitophagie dépendante de la voie PINK1/PARKIN. Outre son intérêt fondamental, ce travail (réalisé en collaboration avec la société de cosmétologie SILAB dans le cadre d’un partenariat industriel CIFRE) ouvre la voie à l’identification d’actifs naturels capables de préserver et/ou restaurer les paramètres fonctionnels mitochondriaux suite à des stress. / The skin is a specialized type of epithelium, both vital and fragile, which evolves with age and is continuously exposed to environmental stresses, such as solar radiations. While data is available about the response of the mitochondrial network and the fate of damaged mitochondria after chemical or environmental stresses in numerous experimental systems, little is known about these processes in skin cells. The aim of the present thesis was to study the impact (i) of UVB irradiation on mitochondrial dynamics (especially mitochondrial fragmentation) in normal human epidermal keratinocytes, which represent the first line of defence against environmental insults; (ii) of poisoning mitochondria of keratinocytes and normal human fibroblasts with chemical drugs. In a first axis, we developed an original method (called Mitoshape) based on confocal microscopy, to estimate qualitatively and quantitatively the morphology of the mitochondrial network within live cells following UVB irradiation. Using this technology, we demonstrated that UVB irradiation induces mitochondrial fragmentation in normal human keratinocytes, and studied the biochemical actors involved in this response. In a second axis, we showed that the use of mitochondrial poisons could damage mitochondria of keratinocytes and normal human fibroblasts and induce bulk autophagy, although it is not possible to formally rule out the involvement of a PINK1/PARKIN-dependent pathway of mitophagy. In addition to its fundamental interest, this work (performed in collaboration with the cosmetic company SILAB in the context of a CIFRE PhD fellowship from ANRT) paves the way for the screening of novel bioactive agents able to protect and restore mitochondria following stresses.
17

Avaliação histológica do tecido adiposo da pele de ratas sob ação de cafeína e Cafeisilane® C / Histological evaluation of fatty tissue under the skin of rats caffeine action and Cafeisilane® C

Clara Tsugumi Nakamura Tano 03 November 2003 (has links)
Hidrolipodistrofia ginóide é uma alteração genuína e loco-regional do panículo adiposo subcutâneo determinante do formato corporal característico da mulher. Várias substâncias ativas podem ser empregadas como anticelulíticos, sendo selecionado para esse trabalho a cafeína e o silício orgânico da cafeína (Cafeisilane® C). Foram desenvolvidas formulações cosméticas (9 emulsões empregando como base cera emulsionante não iônica e 3 géis utilizando polímero carboxivinílico e 1 gel a base de hidroxietilcelulose) contendo cafeína 4,0% p/p; cafeína e benzoato de sódio, ambos a 4,0% p/p e Cafeisilane® C 6,0% p/p e, as mesmas foram submetidas ao estudo de estabilidade acelerada nas seguintes condições: 4° C, ciclos alternados gela/degela (-10° C/45° C), 45° C, -10° C, 22° C e luz solar indireta. Das formulações avaliadas foram selecionadas uma emulsão não iônica e um gel de hidroxietilcelulose para o estudo \"in vivo\" em modelo animal, a fim de avaliar a ação lipolítica da cafeína e Cafeisilane® C. Após análise histológica do dorso depilado das ratas de linhagem Wistar, tanto a cafeína como o Cafeisilane® C apresentaram melhor resposta quando incorporados em emulsão não iônica, ocorrendo redução no diâmetro das células adiposas em 17% para a cafeína e 16% para o Cafeisilane® C. Nesta última preparação, também ocorreu redução de 32% no número de células adiposas. Da forma cosmética gel, apenas o que utilizou como base a hidroxietilcelulose com Cafeisilane® C promoveu redução de 26% no número de adipócitos quando comparado com o gel controle. / Gynoid hydrolipodystrophy is a genuine and regional alteration of the hypodermis, a subcutaneous tissue that determines the characteristic format of the female\'s body. Several active substances can be added in anticellulite cosmetics and in this research there were selected caffeine and siloxanetriol alginate caffeine (Cafeisilane® C). There were developed different cosmetic formulations (9 emulsions with nonionic emulsifying wax, 3 gels with carboxyvinilic polymer and 1 gel with hydroxyethyl cellulose) employing caffeine 4,0% w/w; caffeine and sodium benzoate, both 4,0% w/w, and Cafeisilane® C 6,0% w/w. Formulations above were submitted to the stress testing: 4° C, alternate freeze/thaw cycles (-10° C/45° C), 45° C, -10° C, 22° C and indirect sunlight, as the conditions. We selected one nonionic emulsion and the hydroxyethyl cellulose gel for the in vivo study in animal model for the evaluation of the lypolitic activity of caffeine and Cafeisilane® C. After histological analysis of Wistar\'s depilated back (female rats), as much caffeine as Cafeisilane® C resulted better answers when incorporated in nonionic emulsion, with diameter reduction of the fatty cells in 17% for caffeine and 16% for Cafeisilane® C. Within the Cafeisilane® C emulsion, reduction of 32% in the number of fatty cells occurred. Only hydroxyethyl cellulose gel with Cafeisilane® C promoted the reduction of 26% in the adipocytes numbers, when compared with the control gel.
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Segurança e eficácia antioxidante pré-clínica e clínica de etossomas contendo rutina  de orientação de uso cosmético / Preclinical and clinical safety and antioxidant efficacy of rutin-loaded ethosomes of cosmetic use guidance

Thalita Marcilio Candido 18 October 2016 (has links)
Os cuidados com a pele abrangem gama de ações: cuidados com a exposição solar, alimentação balanceada, não tabagismo e alcoolismo e aplicação de produtos cosméticos, dentre outras. Sabe-se que subtâncias antioxidantes, endógenas e exógenas, auxiliam na manutenção do aspecto saudável e jovial da pele. A rutina, flavonoide pertencente à classe dos flavonóis, apresenta intensa atividade antioxidante, sendo empregada na indústria alimentícia, na prevenção ou tratamento da insuficiência venosa ou linfática e na prevenção aos danos causados pela radiação ultravioleta, por exemplo. Porém, a rutina possui taxa reduzida de permeação cutânea. O presente trabalho destinou-se a incorporar a rutina em etossomas, avaliando a segurança in vitro e in vivo, e a eficácia in vitro e ex vivo. As vesículas foram analisadas quanto ao tamanho de partícula, potencial zeta, taxa de encapsulação da rutina, atividade antirradicalar e potencial de irritação in vitro. As formulações foram avaliadas quanto ao valor de pH, características organolépticas, atividade antioxidante in vitro e ex vivo e permeação cutânea ex vivo. Os etossomas, com e sem rutina, foram obtidos por meio técnica de dispersão mecânica seguida de nova hidratação de filme, com partículas em dimensão nanométrica (369,5 e 247,0 nm, respectivamente). O potencial zeta para os etossomas sem rutina correspondeu à -39,3, enquanto que para aqueles com rutina foi -19,6. A rutina associada ao sistema etossomal foi igual a 80,1%. A rutina nas vesículas etossomais foi capaz de manter o potencial antirradicalar do flavonoide, verificado em ensaio in vitro. Os etossomas com rutina demonstraram-se seguros por meio dos ensaios in vitro e in vivo, sendo aplicados em ensaio posterior de permeação cutânea ex vivo, em voluntários. Foi observada taxa de permeação cutânea superior da rutina em etossomas em comparação com a rutina livre, assim, etossomas contendo rutina tornam-se um possível ingrediente ativo para adição em dermocosméticos destinados para uso contra o envelhecimento precoce. / Skin care covers a range of actions: limited sun exposure, a balanced diet, non smoking and non-alcoholism, and application of cosmetics. It is known that antioxidants, both endogenous and exogenous substances, assist in maintaining a healthy and youthful appearance of the skin. Rutin, a flavonoid belonging to the class of flavonols, has intense antioxidant activity and it is used in the food industry, in the prevention or treatment of venous or lymphatic insufficiency, and to prevent the damage caused by UV radiation. However, rutin has low skin permeation rate. This study was designed to incorporate rutin in ethosomes, evaluating their safety in vitro and in vivo, and efficacy in vitro and ex vivo, in order to assess the improvement of the skin permeation of the flavonoid. The ethosomes with and without rutin were obtained by a mechanical dispersion technique followed by a new lipid film hydration. The ethosomes were analyzed for particle size, zeta potential, encapsulation rate of rutin, antiradical activity and in vitro irritation potential. The formulations were evaluated for pH, organoleptic characteristics, antioxidant activity in vitro and ex vivo and ex vivo skin permeation. The association of rutin with ethosomal vesicles was able to mantain the antiradical potential of flavonoid. The ethosomes with rutin have shown to be safe through in vitro and in vivo safety assays, being applied in subsequent ex vivo tests to evaluate the skin permeation of rutin in human volunteers. A higher skin permeation rate was observed for rutin in ethosomes compared to the free rutin, thus rutin loaded ethosomes have potential as a compound in dermocosmetic formulations for premature aging.
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Molecularly imprinted polymers for applications in cosmetology / Polymères à empreintes moléculaires pour applications en cosmétologie

Li, Bin 11 June 2013 (has links)
Un polymère à empreintes moléculaires (MIP) est un récepteur synthétique supramoléculaire, un matériau possédant des cavités pouvant reconnaître spécifiquement une molécule cible. Il est synthétisé en mettant en contact la molécule cible, avec un mélange de monomères fonctionnels et réticulants qui permettent d'obtenir un réseau polymérique tridimensionnel rigide. L'élimination de la molécule empreinte laissera des sites vides complémentaires de cette dernière. Ces cavités sont maintenant capables de la recapturer spécifiquement. Ces polymères sont utilisés dans les domaines tels que l’extraction en phase solide, la chromatographie d’affinité, la catalyse enzymatique, les biocapteurs et la vectorisation des médicaments. Bien que le concept des MIPs a pour origine les travaux réalisés sur des matériaux sol-gel imprimés dans les années 1930, ces derniers sont restés dans l’ombre jusqu’à l'introduction de polymères organiques imprimés plus versatiles. Par rapport aux MIPs organiques, les MIPs sol-gel présentent quelques avantages comme une plus grande stabilité thermique, une meilleure compatibilité avec l'eau et une plus grande porosité. Dans cette thèse, nous avons développé des MIPs organiques et des MIPs sol-gel pour leur application en cosmétologie et pour la vectorisation de médicaments. Dans la première partie, nous présentons des MIPs pouvant adsorber d’une façon spécifique l’acide oléique (OA), un biomarqueur de l’état pelliculaire sur le cuir chevelu. Pour la préparation des MIPs organiques, nous avons employé plusieurs monomères basiques dont l’acryloylaminobenzamidine (AB), que nous avons tout spécialement synthétisé. Tous les MIPs pouvaient lier l’OA mais beaucoup d’interaction non-spécifique était observé. D’autre part, les MIPs sol-gel présentaient une bonne reconnaissance spécifique et une capacité élevée pour OA; par exemple, un MIP de composition OA:APTES:TEOS = 1:1.6:1.7 pouvait adsorber 625 μmol.g-1 de OA dans le sébum artificiel. Des tests pour capturer l’OA sur le stratum corneum et la peau reconstruite (Episkin) ont également été effectués. La pénétration de l’OA sur les deux types de peau était plus faible en présence de MIP que de NIP. Les MIPs comme matériaux désodorisants font l’objet de la deuxième partie de cette thèse. Des MIPs pouvant adsorber les précurseurs de molécules malodorantes comme les conjugués glutamine des acides (E)-3-méthyl-2-hexénoïque (3M2H) et 3-hydroxy-3-méthyl-hexanoïque (3H3MH) ont été préparés. Le N-hexanoyl glutamine et le N-hexanoyl glutamate ont été utilisés comme template. Nous observons que le MIP synthétisé avec AB comme monomère fonctionnel possède la plus grande capacité d'adsorption pour le N-hexanoyl glutamine, ainsi que pour les précurseurs glutamines des molécules malodorantes. Des résultats préliminaires et très prometteurs ont également été obtenus dans la sueur. La dernière partie de cette thèse concerne des MIPs pour la vectorisation de médicaments. L'acide salicylique (SA) est un médicament efficace utilisé dans le traitement de l’acné. Des MIPs organiques et sol-gel contre SA ont été synthétisés. Les MIPs sol-gel ont une plus grande capacité d’adsorption, 180 μmol.g-1, que les MIPs organiques et ils lient le SA sept fois plus que le NIP. Les tests de relargage du SA ont été effectués dans plusieurs milieux, avec la plus grande efficacité dans l’eau pure. En conclusion, les applications de MIPs en cosmétologie et en vectorisation de médicaments ont étés étudiés. Nos résultats montrent que les MIPs sol-gel sont les plus appropriés pour ce type de travail. / Molecularly imprinted polymers (MIPs) are tailor-made synthetic receptors possessing specific cavities for a given target molecule. They are produced by introducing, into the polymer precursors, guest molecules that act as templates at the molecular level. Interacting and cross-linking monomers are then copolymerized to form a cast-like shell. After removal of the template, cavities complementary to the template in size, shape and position of functional groups are revealed in the polymer, which can now specifically bind the template. Thanks to these specific molecular recognition properties, MIPs have found applications in areas like bio sensors, solid phase extraction, affinity chromatography, catalysis, and drug delivery. Although the MIP concept originated from imprinted silica in the 1930s, imprinted sol-gel materials received little attention afterwards due to the introduction of the more versatile organic polymers as imprinting matrix. However, compared to organic polymers, sol-gels possess higher thermal stability, better water compatibility and larger inner surface area. There have been many applications to biomolecules in aqueous conditions with sol-gel imprinting materials. In this thesis, we have developed organic and silica sol-gel MIPs for applications in cosmetics and drug delivery. MIPs able to adsorb the dandruff-inducing molecule oleic acid (OA) were produced via both the organic and inorganic routes. In the organic MIPs synthesis, different positively charged monomers were used, one of which, acryloyl aminobenzamidine, was specifically synthesized. Although some binding of oleic acid was obtained, specificity and capacity of these polymers were not satisfying. Sol-gel MIPs, on the other hand, exhibited good specific recognition and high binding capacity for OA. A MIP of the composition OA:APTES:TEOS= 1:1.6:1.7 yielded a capacity of 625 μmol.g-1 in artificial sebum. Furthermore, tests were carried out to capture OA on stratum corneum and reconstructed skin (Episkin). Less penetration of OA was observed in the presence of a MIP than with a non-imprinted control polymer. Deodorant materials are another topic of this thesis. MIPs that are able to adsorb certain precursors of odorant molecules, the glutamine conjugates of (E)-3-methyl-2-hexenoic acid (3M2H) and 3-hydroxy-3-methyl-hexanoic acid (3H3MH) were prepared. N-hexanoyl glutamine and N-hexanoyl glutamate were used as templates. After optimization of the MIP composition, we found that MIPs synthesized with acryloyl aminobenzamidine as functional monomer had the highest adsorption capacity for N-hexanoyl glutamine, and also recognised the glutamine targets of 3M2H and 3H3MH. Some preliminary promising binding results were obtained in artificial sweat. The third part of this work concerns a drug delivery MIP. Salicylic acid (SA) is a drug used to treat acne. SA-imprinted polymers were prepared via both organic imprinting and the sol-gel process.Compared to organic MIPs, sol-gel MIPs have a higher capacity, 180 μmol.g-1, and 7 times higher binding than to a non-imprinted control polymer was observed. Release tests were carried out in different aqueous media, the most efficient drug release was observed in pure water. In conclusion, applications of molecularly imprinted polymers for cosmetics and drug delivery have been investigated. Our results demonstrate the great potential of in particular sol-gel MIPs for these purposes.
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Padronização de cultura de pele humana para avaliação de toxicidade e eficácia de produtos cosméticos / Standardization of human skin culture for toxicity evaluation and efficacy of cosmetic products

Ribeiro, Cláudio de Jesus 15 September 2003 (has links)
A legislação brasileira para cosméticos exige que os apelos mercadológicos desses produtos sejam comprovados. Os testes in vivo utilizando animais para avaliação desta categoria de produtos ou os princípios ativos nela contidos são, atualmente, bastante criticados. O presente trabalho teve como objetivo desenvolver um modelo de cultura de pele humana e avaliar a viabilidade dos melanócitos durante o período de 7 dias. A manutenção do tecido foi avaliada pela observação microscópica após coloração com HE e Masson, os melanócitos ativos pela reação de DOPA e a melanina pela coloração Fontana-Masson. Fragmentos de pele com 2mm2 mantidos em meio de Leibovitz à temperatura ambiente e atmosfera com 95% de ar e 5% de CO2, sofreram menos alterações morfológicas comparados aos mantidos em DMEM à temperatura de 37°C, 5% de CO2, 40% de O2 e 55% de N2. Fragmentos com 20mm2 mantidos em Leibovitz apresentaram alterações semelhantes aos de 2mm2. Células em divisão foram observadas em amostras de pele mantidas em Leibovitz enriquecido com SFB e ácido retinóico. A presença de melanina foi verificada durante todo o período de cultura, bem como a dos melanócitos, que se mostraram DOPA reativos. A radiação UVA/UVB, empregada com a finalidade de verificar se os melanócitos sofriam alguma alteração na atividade e morfologia, não provocou qualquer mudança nestas células, por outro lado induziu uma redistribuição da melanina nos queratinócitos dos fragmentos irradiados. Os resultados obtidos mostraram que é possível manter pele humana em cultura por 7dias, bem como a viabilidade dos melanócitos e sugere ser possível a aplicação do modelo estudado em futuros ensaios de eficácia e segurança de produtos tópicos. / The Brazilian law for cosmetics demands that the marketing of these products should be proofed. The tests in vivo utilizing animals for evaluation of this category of products or the active components in it, are very criticized nowadays. The present work had as an objective to develop a model of culture of human skin, and evaluate the viability of the melanocytes during a period of 7 days. The maintenance of the tissue was evaluated by the microscopic observation after coloring with HE and Masson, the active melanocytes by the DOPA reaction and the melanin by coloring of Fontana-Masson. Fragments of skin with 2mm2 kept in Leibovitz at room temperature and atmosphere with 95 % of air and 5 % of CO2, presented less morphologic alterations than the ones kept in DMEM at the temperature of 37, 5% of CO2, 40% of O2 and 55% of N2. Fragments with 20mm2 kept in Leibovitz presented similar alterations to the 2mm2. Mitotic cells were observed in samples of skin kept in enriched Leibovitz with FBS and retinoic acid. The presence of melanin was verified through all of the period of culture as well as the melanocytes that were DOPA-reactive. The radiation UVA/UVB, used with the aim of verifying if the melanocytes presented any alteration in the activity and morphology, didn\'t provoke any changes in the cells, on the other hand it induced a redistribution of the melanin in the keratinocytes of the irradiated fragments. The results obtained showed that it is possible to keep the human skin in culture for 7 days as well as the viability of melanocytes, and suggests the possibility of application of the studied model in future research on the efficacy and the safety of topic products.

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