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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.
91

Efeitos de um derivado polifenólico da Camellia sinensis na hidrocefalia experimental induzida em ratos Wistar / The effects of a Camellia sinensis-derived polyphenolic in induced experimental hydrocephalus in Wistar rats

Carlos Henrique Rocha Catalão 30 January 2013 (has links)
A hidrocefalia é uma síndrome complexa caracterizada pelo acúmulo de líquido cérebro-espinal no interior das cavidades ventriculares. Considerando a sua fisiopatologia de caráter multifatorial sendo um dos fatores envolvidos o estresse oxidativo desencadeado pela peroxidação lipídica e formação de radicais livres, este trabalho visa estudar o possível efeito neuroprotetor proveniente do polifenol galato de epigalocatequina (EGCG) na hidrocefalia experimental. Foram utilizados ratos da linhagem Wistar (N=56), com 7 dias de idade. Os filhotes foram submetidos à indução da hidrocefalia pelo método da injeção intracisternal de caulim a 20%. O polifenol foi administrado intraperitonealmente por 9 ou 20 dias consecutivos a partir da indução da hidrocefalia. Aferição do peso corporal diário e testes comportamentais foram realizados. Dez ou 21 dias após a indução da hidrocefalia os animais, profundamente anestesiados, foram sacrificados através da perfusão cardíaca com solução salina. Seus encéfalos foram removidos, fixados com paraformaldeído 3% em tampão fosfato 0,1M e processados para inclusão em parafina. Preparações histológicas foram realizadas para a análise por coloração hematoxilina eosina, solocromo-cianina e imunoistoquímica para GFAP e Ki67. Os diferentes parâmetros de avaliação demonstraram que os animais tratados com o polifenol por 9 dias consecutivos apresentaram redução da atividade astrocitária através da imunomarcação pelo GFAP no corpo caloso, cápsula externa e matriz germinativa; além de apresentarem corpo caloso mais espesso e mielinizado, exibindo uma tonalidade azul mais intensa evidenciada pela coloração solocromocianina. Apesar desses resultados demonstrarem um possível efeito neuroprotetor na fase inicial de instalação da doença, estudos adicionais devem ser realizados para obtenção de uma terapêutica eficiente e segura para o aprofundamento com testes clínicos. / Hydrocephalus is a complex syndrome, characterized by the accumulation of cerebrospinal fluid in cerebral ventricles. Considering its multifactorial pathophysiology, one of the factors being the oxidative stress triggered by lipid peroxidation and free radical formation, this work aims to study the possible neuroprotective effect of the polyphenol epigallocatechin gallate (EGCG) in experimental hydrocephalus. Seven-day old Wistar rats (N=56) were used in this study. The pups were subjected to hydrocephalus induction by kaolin 20% through intracisternal injection. The polyphenol was administered intraperitoneally for 9 or 20 days from the induction of hydrocephalus. Measurement of daily body weight and behavioral tests were performed. The animals, deeply anesthetized, were sacrificed by cardiac perfusion with saline 10 or 21 days after induction of hydrocephalus. Their brains were removed, fixed with 3% paraformaldehyde in 0.1 M phosphate buffer, and processed for paraffin embedding. Preparations were made for histological analysis by hematoxylin and eosin, solochrome-cyanine and immunohistochemistry for GFAP and Ki67. The different evaluated parameters showed that animals treated with the polyphenol for 9 consecutive days displayed reduction on the reactive astrocytes GFAP immunostaining at the corpus callosum, external capsule and germinal matrix, also having thicker and more myelinated corpus callosum exhibiting a more intense blue staining by solocromo-cyanine. Although these results demonstrate a possible neuroprotective effect at the initial onset of the disease, additional studies should be performed to obtain an effective and safe therapy for deeper studies in clinical trials.
92

Produção, purificação, caracterização e aplicação de tanase de Aspergillus melleus URM 5827 produzida por fermentação em estado sólido utilizando sementes de achachairú (Garcinia humilis (Vahl) C. D. Adam)

LIU, Tatiana Pereira Shiu Lin 25 February 2016 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-05-19T12:41:06Z No. of bitstreams: 1 Tatiana Pereira Shiu Lin Liu.pdf: 880008 bytes, checksum: 5eed3ce34aa09053744a3f45eca49b25 (MD5) / Made available in DSpace on 2016-05-19T12:41:06Z (GMT). No. of bitstreams: 1 Tatiana Pereira Shiu Lin Liu.pdf: 880008 bytes, checksum: 5eed3ce34aa09053744a3f45eca49b25 (MD5) Previous issue date: 2016-02-25 / Tannin acylhydrolase (TAH) known as tannase (E.C:3.1.1.20) is an enzyme which hydrolizes esters and lateral bonds of hydrolizable tannins. The tannic acid is a typical hydrolizable tannin, which can be hydrolized by tannase along with glucose and gallic acid. Tannase can be obtained from vegetables, animal and microbial sources. From those, the last is the most important source to obtain the enzyme. Green tea has several substances, among which catechins are a major source of antioxidant, which help in maintaining the organism.The activity and purification of tannase produced by Aspergillus melleus URM 5827 was evaluated by semi solid fermentation using seeds of mangosteen (Garcinia humilis (Vahl) C. D. Adam) as substract. Forty two cultures fungical cultures of Aspergillus were used for qualitative selection purposes in order to verify potential for tannase production. After selecting cultures, it was performed a semi solid fermentation using seeds of mangosteen as substrate. A factorial planning (2³) was used to verify the influence of production variables such as: quantity of substrate; initial moisture and amount of tannic acid over tannase activity. The purification was evaluated by ionic change chromatography at DEAE-Sephadex. Maximum activity was produced by Aspergillus melleus URM 5827 with 452.55 units per gram of dry-based substract (U/gss) using 5.0 grams of substrate, with initial moisture of 60% and 2% of tannic acid through 48 hours fermentation. The purified enzyme has a molecular weight of 69.52 kDa on Superdex G-75, while on SDS-PAGE electrophoresis showed 66.5 kDa. As for the characterization, the optimum pH and temperature was 5.5 and 40ºC, respectively, achieving thermostability at 30ºC. Coughing increases the antioxidant activity of green tea significantly. The results obtained in this study show the promising potential of tannase produced by Aspergillus melleus URM 5827 and its use in improving the antioxidant potential of green tea. / Tanino acil hidrolase (TAH) conhecida como tanase (E.C:3.1.1.20) é uma enzima que hidrolisa ésteres e ligações laterais de taninos hidrolisáveis. O ácido tânico é um típico tanino hidrolisável, que pode ser hidrolisado por tanase em glicose e ácido gálico. A tanase pode ser obtida a partir de fontes vegetais, animais e microbianas, sendo o meio microbiológico a fonte mais importante de obtenção desta enzima. O chá verde apresenta várias substâncias, dentre elas, as catequinas que são uma importante fonte de antioxidante, que ajudam na manutenção do organismo.A atividade e a purificação de tanase produzida por Aspergillus melleus URM 5827 foi avaliada por fermentação em estado sólido utilizando como substrato sementes de achachairú (Garcinia humilis (Vahl) C. D. Adam). Foram utilizadas 42 culturas de fungos do gênero Aspergillus para seleção qualitativa das culturas com potencial para produção da tanase. Com a cultura selecionada foi realizada uma fermentação em estado sólido utilizando sementes de achachairú como substrato. Um planejamento fatorial (23) foi utilizado para analisar a influência das variáveis de produção: quantidade de substrato, umidade inicial e quantidade de ácido tânico sobre a atividade da tanase. A purificação foi avaliada por cromatografia de troca iônica em DEAE- Sephadex. A máxima atividade foi produzida por Aspergillus melleus URM 5827 com 452,55 unidades por grama de substrato na base seca (U/gss) utilizando 5,0 g de substrato, com umidade inicial de 60% e 2,0% de ácido tânico em 48 horas de fermentação. A enzima purificada apresentou peso molecular de 69,52 kDa em Superdex G-75, enquanto que em eletroforese SDS-PAGE apresentou 66,5 kDa. Quanto a caracterização, apresentou pH e temperatura ótima de 5,5 e 40ºC respectivamente, obtendo termoestabilidade a 30ºC. A atividade enzimática na presença de íons, surfactantes e inibidores de protease, foi inibida na presença dos íons ZnCl2, ZnSO4 e dos surfactantes triton X-100, SDS, reduzida com os íons CaCl2, KCl, NaCl, MgSO4, CuSO4, dos surfactantes Tween 20, Tween 80 e dos inibidores de protease EDTA e β-mercaptoetanol. A tanase aumentou a atividade antioxidante do chá verde significativamente. Os resultados obtidos no presente estudo, mostram o potencial promissor da tanase produzida por Aspergillus melleus URM 5827 e na sua utilização no aumento do potencial antioxidante do chá verde.
93

Estudo comparativo entre epigalocatequina-3-galato e sibutramina em ratos Wistar com obesidade induzida

RIBEIRO, Libania Lima 26 February 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-26T12:29:26Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO DE PATOLOGIA LIBÂNIA L. RIBEIRO.pdf: 3636176 bytes, checksum: c91dc469ad8c94f010a143b161defe01 (MD5) / Made available in DSpace on 2016-07-26T12:29:26Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO DE PATOLOGIA LIBÂNIA L. RIBEIRO.pdf: 3636176 bytes, checksum: c91dc469ad8c94f010a143b161defe01 (MD5) Previous issue date: 2016-02-26 / A obesidade é uma das doenças mais estudadas no mundo, tendo em vista seu crescente aumento e envolvimento em várias comorbidades. Nesse contexto, o presente trabalho visa avaliar a substância epigalocatequina-3-galato (EGCG), a catequina mais ativa da planta Camellia sinensis, no emagrecimento de ratos após indução de obesidade com dieta ocidentalizada, assim como comparar seu efeito com o da sibutramina. O estudo foi realizado através de método experimental comparativo controlado, desenvolvido no biotério de Nutrição da Universidade Federal de Pernambuco, no período de fevereiro de 2015 a janeiro de 2016. Para tal, foram utilizados 32 ratos Wistar machos, procedentes de cria habitual e manipulada, para compor quatro grupos de oito ratos, a saber: grupo controle salina (CSAL) grupo controle, proveniente de cria habitual, que fez uso da dieta Presence® e foi tratado com NaCl 0,9%; grupo ocidentalizado salina (OSAL), obeso, cria reduzida, alimentado com dieta ocidentalizada e tratado com NaCl 0,9%; grupo ocidentalizado sibutramina (OSIB), obeso, cria reduzida, alimentado com dieta ocidentalizada e tratado com sibutramina 7,5 mg/Kg e o grupo ocidentalizado epigalocatequina-3-galato (OEGCG), obeso, cria reduzida, alimentado com dieta ocidentalizada e tratado com EGCG 50mg/Kg/dia. Ao atingir o fenótipo obeso e findar oito dias de tratamento, foram observados dados murinométricos, consumo alimentar, exames hematológicos e histológicos de fígado, rins e coração. Os resultados obtidos mostraram que os grupos OSIB e OEGCG apresentaram importante queda no consumo alimentar e peso corporal. O trabalho mostrou que a EGCG não apresentou toxicidade para os animais e foi capaz de reduzir significativamente o peso dos ratos obesos com intensidade comparável à da sibutramina, além de prevenir ou promover regressão de esteatose hepática e esteato hepatite. / Obesity is one of the most studied diseases in the world, given its increasing involvement in various comorbidities. In this context, this study aims to evaluate the epigallocatechin-3-gallate (EGCG), Camellia sinensis’s most active catechin, in weight loss of rats after an obesity induction with occidentalized diet, as well as to compare its effect with sibutramine’s. The study was made through a controlled comparative experimental method, developed at the nutrition vivarium of the Federal University of Pernambuco, between February 2015 and January 2016. For that matter, 32 male Wistar mice were used, coming from a manipulated and standard spawn, to compose four groups of eight mice, namely: saline control group (CSAL), coming from a standard spawn, which made use of Presence® diet and was treated with NaCl 0.9%; saline occidentalized group (OSAL), obese, fed with westernized diet and treated with NaCl 0.9%; sibutramine occidentalized group (OSIB), reduced spawn, fed with occidentalized diet and treated with sibutramine 7.5 mg/Kg; and epigallocatechin-3-gallate occidentalized group (OEGCG), reduced spawn, fed with occidentalized diet and treated with EGCG 50 mg/Kg/day. Upon reaching the obese phenotype and completing eight days of treatment, murinometric data, food consumption, hematological and histological tests of liver, kidney and heart were observed. The results reported that groups OSIB and OEGCG demonstrated significant decrease in food consumption and weight. A biochemical and histological evaluation of the animals showed no toxicity of the drugs, after the treatment period. The study found that EGCG showed no toxicity in animals and that it was able to significantly reduce the weight of obese mice with intensity comparable to sibutramine’s, as well as to prevent or promote regression of hepatic steatosis and steatohepatitis.
94

Análise da expressão de genes relacionados ao metabolismo energético e lipídico em mulheres com obesidade grau III após suplementação de extrato de chá verde descafeinado / Analysis of gene expression related energy and lipid metabolism in women with obesity grade III after decaffeinated green tea extract supplementation

Driele Cristina Gomes Quinhoneiro 19 August 2016 (has links)
A obesidade surge como um distúrbio neuroendócrino, com atuação de fatores de risco ambientais e genéticos, e recentemente centenas de genes tem sido associados ao controle do peso corporal e metabolismo energético. Frente à alta incidência e prevalência de obesidade na população, empregam-se estratégias com a finalidade de elevar a eficácia de perda de peso, como por exemplo, o uso de compostos bioativos presentes nos alimentos, com destaque para 3-galato de epigalocatequina (GEGC) presente no chá verde. As dietas ricas em polifenóis apresentam efeitos antiobesogênicos, possivelmente por sua interação direta ou indireta com o tecido adiposo. O presente estudo teve como objetivo verificar a expressão de UCPs, PLIN1, PPARG2 e ADRB3 em tecido adiposo subcutâneo abdominal de mulheres com obesidade grau III antes e após oito semanas de suplementação com extrato de chá verde descafeinado e associar com variáveis antropométricas, taxa metabólica de repouso (TMR), oxidação de substratos e consumo alimentar. A amostra foi composta por 11 mulheres com obesidade grau III submetidas à suplementação de 450 mg de chá verde por oito semanas (grupo intervenção) e 10 mulheres eutróficas (grupo controle). Tratou-se de um estudo longitudinal e foram coletadas medidas antropométricas de peso e estatura para cálculo do Índice de Massa Corporal (IMC); circunferência abdominal (CA); composição corporal (massa livre de gordura e massa gorda) por bioimpedância elétrica; ingestão alimentar por recordatórios de 24h, TMR por calorimetria indireta e análise de expressão gênica por reação em cadeia da polimerase em tempo real (RT-qPCR). Após oito semanas de suplementação, o grupo intervenção não apresentou alterações nas variáveis antropométricas, de composição corporal, TMR e oxidação de substratos. Ao comparar o grupo controle e intervenção, observou-se no primeiro valores menores de IMC, CA, massa livre de gordura, massa gorda, TMR e oxidação de lipídios. Dos genes analisados, houve aumento da expressão de UCP3 após o período de suplementação (p=0,026). As análises de correlação e regressão linear mostraram que as mulheres com obesidade grau III antes da suplementação de chá verde que expressavam mais UCP2 possuíam menor peso (p=0,043) e massa gorda (p=0,045). Ainda, às que ingeriam mais calorias por dia, exibiram maior expressão de UCP2 (p=0,045). Conclui-se que a suplementação de extrato de chá verde descafeinado, por 8 semanas, em mulheres com obesidade grau III, não altera a expressão de UCP1, UCP2, PLIN1, PPARG2 e ADRB3, o que poderia explicar a manutenção das variáveis antropométricas, composição corporal, taxa metabólica de repouso e oxidação de substratos. Por outro lado, há o aumento da expressão de UCP3 após a intervenção, sugerindo um possível mecanismo de adaptação desse gene atuando na manutenção do peso. / Obesity emerges as neuroendocrine disorder, with action of environmental and genetic risk factors, and recently hundreds of genes have been associated with management of body weight and energy metabolism. As obesity rates continue to climb in population, an increased number of strategies are employed in order to improve effectiveness of weight loss, such as use of bioactive compounds in foods, especially Epigallocatechin gallate (EGCG) present in green tea. Polyphenol-rich foods have anti-obesogenic effects, possibly by its direct or indirect interaction with adipose tissue. This study aimed to verify expression of UCPs, PLIN1, PPARG2 and ADRB3 in abdominal subcutaneous adipose tissue of women with obesity grade III before and after eight weeks of supplementation with decaffeinated green tea extract and associate with anthropometric, metabolic rate (RMR), substrate oxidation and energy intake. The sample consisted of 11 women with obesity grade III submitted to supplementation of 450 mg of green tea for eight weeks (intervention group) and 10 women eutrophic (control group). This was a longitudinal study and were collected anthropometric measurements of weight and height to calculate body mass index (BMI); abdominal circumference (AC); body composition (fat-free mass and fat mass) by bioelectrical impedance analysis; energy intake by 24-hour dietary recalls; TMR by indirect calorimetry and gene expression analysis by real-time PCR (RT-qPCR). After eight weeks of supplementation, the intervention group showed no changes in anthropometric variables, body composition, TMR and substrate oxidation. When comparing control group and intervention, is noted that first had lower values of BMI, WC, fat-free mass, fat mass, RMR and oxidation of lipids. Genetic analysis show an increased expression of UCP3 gene after the supplementation period (p = 0.026). The correlation and linear regression analysis revealed that women with obesity grade III before green tea supplementation that expressed more UCP2 had lower weight (p = 0.043) and fat mass (p = 0.045). Still, those that had higher energy intake, exhibited increased expression of UCP2 (p = 0.045). We conclude that the decaffeinated green tea extract supplementation for 8 weeks in women with obesity grade III, does not alter the expression of UCP1, UCP2, PLIN1, PPARG2 and ADRB3, which could explain maintenance of anthropometric variables, composition body, resting metabolic rate and substrate oxidation. Moreover, there is increased UCP3 expression after supplementation, suggesting a possible adjustment mechanism of this gene acting in weight management.
95

Microencapsulação de compostos bioativos de Camellia sinensis em sistemas lipídicos por spray drying / Microencapsulation of bioactive compounds of Camellia sinensis in lipid systems by spray drying

Vanessa Aparecida Secolin 06 February 2015 (has links)
O chá verde (Camellia sinensis) é reconhecido mundialmente por seu alto teor de polifenóis, em especial as catequinas. As catequinas estão relacionadas à prevenção de várias doenças degenerativas, como o câncer e diabetes, devido ao grande potencial antioxidante. Contudo, vários incovenientes precisam ser superados para aprimorar o uso destes produtos, principalmente em relação à sua biodisponibilidade. O desenvolvimento de carreadores lipídicos na encapsulação de compostos bioativos é uma tecnologia recente capaz de resolver vários problemas de biodisponibilidade apresentadas pelos produtos naturais, produzindo uma estrutura capaz de proteger os compostos ativos. O objetivo deste trabalho foi o desenvolvimento de uma formulação utilizando carreador lipídico, empregando métodos de secagem para aumentar a estabilidade dos compostos bioativos, enfatizando-se processos de preparação, tipo de excipientes e procedimentos para a caracterização físico-química, estabilidade e avaliação da atividade antioxidante in vitro do produto final. Os compostos bioativos foram extraídos a partir das folhas secas e moídas de chá-verde através do processo de maceração dinâmica, sendo filtrado, concentrado e liofilizado. A formulação foi desenvolvida utilizando o sistema de balanço hidrófilo-lipófilo (EHL) com tensoativos nãoiônicos e co-solvente, e caracterizados pelas análises organolépticas, centrifugação, reologia, microscopia óptica, distribuição de tamanho e potencial zeta. Para a etapa de secagem, selecionou-se a formulação mais estável. As formulações foram secas em spray dryer de escala laboratorial a uma vazão de 4,0 g/min, e temperaturas de 100, 120 e 150 °C. O desempenho de secagem foi avaliado pela recuperação do produto. Os pós obtidos por spray drying foram caracterizados quanto ao teor de umidade, atividade da água, densidade, distribuição granulométrica, propriedades de fluxo, cristalinidade, morfologia e redispersibilidade. Após, se avaliou a atividade antioxidante do produto em óleo vegetal (óleo de soja) utilizando o teste acelerado de estabilidade oxidativa em Rancimat®. O EHL, o tipo de tensoativo e a técnica de preparo da formulação influenciaram diretamente na estabilidade do sistema. Para as formulações estudadas, o tensoativo que conferiu uma maior estabilidade foi o Gelucire® 44/14, sendo selecionado para prosseguimento com o processo de secagem das composições. O rendimento do processo atingiu em média 51,3 ±3,5 %, típico para secadores do tipo spray dryer em escala laboratorial. A maioria das partículas apresentou aparência arredondada, sem presença visível de porosidade, independente do adjuvante (lactose ou trealose). O produto apresentou baixa atividade de água (<= 0,22) e teor de umidade (<= 1,79). O aumento da temperatura de secagem provocou um ligeiro aumento no diâmetro médio de partícula quando a lactose foi utilizada como adjuvante de secagem (9,8 ± 5,9 ?m para 13,65 ± 8,4 ?m). Os pós obtidos tiveram baixa densidade, sendo menor em temperaturas mais altas. O índice de Carr e Fator de Hausner (15 % e < 1,25, respectivamente) indicaram boas propriedades de compressão e fluidez. O produto foi prontamente redispersível, recuperando facilmente sua consistência e características originais. A avaliação da estabilidade oxidativa acelerada utilizando Rancimat demonstrou que o processo de encapsulação conferiu uma maior solubilidade e proteção dos compostos bioativos, levando ao aumento da atividade antioxidante. Os resultados aqui relatados confirmam a viabilidade da encapsulação dos compostos bioativos de Camellia sinensis em carreadores lipídios empregando o processo de spray drying. O produto apresenta potencial de aplicação como matéria-prima para a produção de formas orais, inclusão em produtos nutracêuticos e cosméticos / Green tea, a product made from Camellia sinensis leaves, is recognized worldwide by its high polyphenol content, in special the catechins. Tea catechins are linked to the prevention of several degenerative diseases as cancer and diabetes. However, several drawbacks need to be overcome in order to increase the use of this products, being their bioavailability one of the upmost. The development of carrier lipid based containing bioproducts is a recent technology, which can solve several bioavailability problems presented by natural products, producing a structure which confer protection to active compounds. The aim of this work was the development of carrier lipid based compositions containing bioactive compounds of Camellia sinensis (green tea) by spray drying evaluating processes of preparation, type of excipients and characterization of physicochemical properties and evaluation the antioxidant activity in vitro of the product. Bioactive compounds from dried and milled green tea leaves was extracted by dynamic maceration, filtered, concentrated and freeze-dried. The formulation was developed through the utilization of Hydrophilic Lipophilic Balance System (HLB) using the non-ionic surfactants and a co-solvent and characterized by organoleptic analysis, centrifugation, rheology, optical microscopy, size distribution and zeta potential. The most stable compositions were submitted to spray drying. The compositions were dried in a labscale spray dryer at flow rate of 4.0 g/min at temperatures of 100, 120 and 150 °C. The spray drying performance was characterized by determination of the powder production yield. Spray dried powders were characterized by moisture content, water activity, density, size distribution, flow properties, crystallinity, morphology, and redispersibility. After, it was evaluated the antioxidant activity of the product in vegetable oil (soybean oil) using the accelerated oxidative stability test Rancimat®. The HLB, the type of surfactant and the preparation method of the formulation influenced the system stability. For the formulations studied, the surfactant which confers the greater stability was Gelucire® 44/14, which was selected to prepare composition for spray drying. The powder production yield falls around 51.3 ±3.5 %, typical for lab scale spray dryers. Wrinkled and rounded particles, without visible presence porosities were mostly generated, independent of the adjuvant (trehalose or lactose). The product presented low water activity (<= 0.20) and low moisture content (<= 1.79). Increasing in drying temperature caused a slight increase in mean particle diameter, when lactose was used as drying carrier (9.8 ±5.9 ?m to 13.65 ±8.4 ?m). Low density powders were generated, but density tends to be lower at high drying temperatures composition were submitted to spray drying. Carr index and Hausner ratio of the product (< 15% and < 1.25, respectively) were indicative of good compressive and flow properties. The product was promptly redispersible, regaining its original consistency straight forwardly. The accelerated oxidative stability using the Rancimat demonstrated that the encapsulation increased the solubility and protection of bioactive compounds, resulting to increased antioxidant activity of the product. The results here reported confirm the feasibility of entrapment of herbal bioactive compounds of Camellia sinensis in lipid carrier by spray drying. The product has potential to be used as raw material for production of oral dosage forms, inclusion in nutraceutical and cosmetic products.
96

Efeito do chá verde sobre o epitélio de revestimento e a capacidade de cicatrização / Effects of green tea on lining epithelium and wound healing.

Ana Luiza de Almeida Neves 30 October 2009 (has links)
O chá verde e um produto da planta Camellia sinensis e apresenta em sua composição mais de 200 substâncias, sendo as mais conhecidas as catequinas, ou polifenóis, ou flavonóides, mas há também os polissacarídeos conjugados, os aminoácidos, cafeína e vitaminas. Estudos têm demonstrado que o consumo regular de chá verde reduz o risco de câncer, protegendo contra seus eventos iniciais e retardando a progressão da doença, que possui ação antioxidante e propriedades bactericidas e pode ser um coadjuvante no tratamento de diabetes, hipertensão e hipercolesterolemia. O objetivo desse trabalho foi avaliar e comparar as características dos epitélios de revestimento da pele e da mucosa bucal, assim como o processo de cicatrização, em animais controle e os que fizeram uso de chá verde. Ratos Wistar receberam chá verde para beber no lugar de água. O controle foi realizado com animais com pesos e idades semelhantes que receberam água de torneira para beber. Após 2 semanas, controles e tratados foram submetidos à cirurgia em seu dorso, sendo essas áreas avaliadas aos 1, 3 e 7 dias de pós-operatório (PO). Para avaliação dos epitélios sem cirurgia foram utilizados animais tratados com chá verde durante 2 e 8 semanas e foram utilizados os epitélios da pele, da língua, dos palatos mole e duro e da gengiva. Na avaliação da cicatrização, observou-se aumento de epitélio neoformado aos 3 dias PO, e diminuição de edema tanto aos 3, quantos aos 7 dias PO. Observaram-se, na avaliação dos epitélios, alterações nucleares e epiteliais nos períodos iniciais de uso do chá verde, que tendem a ser normalizadas com o uso continuado; foram avaliados, também, os valores de colesterol total, triglicérides, HDL, VLDL e LDL e observou-se diminuição significativa principalmente nos valores de triglicérides. / Green tea, a product from Camellia sinensis, consists of over 200 components. The most known are the catechins, or polyphenolic compounds, or flavonoids, but it contains also polysacharide conjugates, amino acids, caffeine and vitamins. Studies have suggested that the regular use of green tea reduces the risk of cancer, protecting against initial events and progression of the disease, that may act as antioxidant, has bactericidal properties, and that green tea consumption may be an adjuvant in the treatment of diabetes mellitus, hypertension and hypercholesterolemia. The purpose of this study was the evaluation the oral epithelium, skin epithelium and wound healing process. Our experimental study was carried out with Male Wistar rats, separated in two groups, experimental and control. To the control group were served water ad libitum, and the experimental group received green tea instead of water. After 2 weeks of experimental period, all the animals, control and experimental groups, suffered surgical wounds on the dorsum. The animals were sacrificed on days 1, 3 and 7 after surgery. Skin samples were used for light microscopy evaluation. Our results allow us to observe that the experimental group (green tea drinking) presented accelerated epithelial neoformation on day 3 after surgery, when epithelial neoformation is in initial phases. To epithelium evaluation were used animals receiving green tea for 2 and 8 weeks (skin, tongue, palates and gun were used). We observed epithelial and nuclear changes, but this values tend of return to control patterns with continued use. We also evaluated lipoproteins, such as total cholesterol, triglycerides, HDL, LDL and VLDL. Triglycerides values were significantly decrease in experimental group.
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The effects of combinations of a green tea extract and an active ingredient thereof, with standard antiretroviral drugs on SC-1 cells infected with the LP-BM5 virus

Dias, Andreia Sofia Pires 13 January 2009 (has links)
The introduction of highly active antiretroviral therapy (HAART) has resulted in a significant decrease in the mortality and morbidity associated with the acquired immunodeficiency syndrome (AIDS). Several problems are associated with HAART and include high costs of treatments, poor availability of drugs in low-income countries, poor compliance, severe adverse effects and drug resistance. Therefore, the focus of current research is the development of new antiretroviral drugs, improved treatment strategies and the discovery of new drugs derived from plants. Green tea (GT) and its active constituent epigallocatechin gallate (EGCg) have been found to be protective against cancer, cardiovascular and neurodegenerative diseases and were found also to have antimicrobial, antimalarial and more importantly antiviral activity. EGCg, in vitro has been shown to inhibit the human immunodeficiency virus (HIV) viral enzymes reverse transcriptase and protease, destroy viral particles and interfere with the attachment of gp120 to cellular receptor CD4. The aims of this study were firstly to investigate the in vitro antiretroviral activity of GT and EGCg on the LP-BM5 defective murine leukemia virus (MuLV) that induces a disease in C57BL/6 mice similar to AIDS in humans and secondly to investigate the effects of GT and EGCg on the in vitro cytotoxicity and antiretroviral activity of current antiretroviral drugs zidovudine (AZT), indinavir (IDV), hydroxyurea (HU) and chloroquine (CQ). To achieve the above aims an in vitro model that represents cell-to-cell spreading of the LP-BM5 MuLV was developed. Firstly the presence of the LP-BM5-defective virus in the BM5 cell line was confirmed using transmission electron microscopy (TEM) to identify viral particles, PCR and RT-PCR were used to determine the presence of viral DNA and RNA respectively and viral infectivity was confirmed in C57BL/10 mice. The cytotoxicity of each drug and combination was evaluated with the MTT assay in the SC-1 cell line, the predominant cell type in the in vitro cell culture model. GT was the least cytotoxic, followed by AZT, IDV, EGCg, HU and CQ. Co-cultures (BM5:SC-1, 1:10000) that represented cell-to-cell transmission of the virus were established. Real time PCR for proviral DNA revealed that IDV, AZT and HU completely suppressed, CQ dose dependently reduced while GT and EGCg had no effect on viral transmission. Findings using AZT and IDV thus validated the use of this in vitro co-culture model for first line screening of new drugs and plant extracts. The effect of GT or EGCg in combination with AZT, IDV, HU or CQ was also evaluated as GT or EGCg could enhance the antiretroviral effects or decrease cellular toxicity of these drugs. For GT with AZT a mix of synergism and antagonism on cell toxicity was observed with little to no effect on the antiretroviral activity of AZT. Antagonism on cell toxicity was observed for GT with IDV, with no effect on the antiretroviral activity of IDV. In contrast EGCg significantly reduced the antiretroviral activity of IDV. A strong antagonistic effect was observed for GT with HU, with GT reducing the antiretroviral effect of HU. For combinations of AZT with EGCg and HU with EGCg a similar effect was observed as for AZT and HU respectively combined with GT. Synergism in cytotoxicity was observed between GT and CQ associated with a significant decrease in viral loads while EGCg combined with CQ had an opposite effect at higher concentrations. In conclusion, the in vitro co-culture model of BM5 and SC-1 cells was successfully used to evaluate combinations of GT and EGCg with AZT, IDV, HU and CQ. Interesting and often contradicting effects were observed, such as seen for IDV in combination with GT and EGCg as well as CQ in combination with GT and EGCg. These effects may be of clinical relevance and further investigation is warranted. / Dissertation (MSc)--University of Pretoria, 2009. / Anatomy / unrestricted
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Epigallocatechin-3-gallate and recombinant human activated protein C and the modulation of acute pancreatitis

Idicula Babu, Benoy January 2012 (has links)
Effective management of acute pancreatitis has for centuries eluded mankind. The disease has a wide spectrum of presentation; the milder form is usually a self limiting condition, whereas the severe form presents as a highly morbid and frequently lethal attack. The ability to predict disease progression on admission would aid in the comprehensive and multidisciplinary management of patients. The perfect predictor of disease progression has been an elusive factor hindering the management of the disease. On systematically reviewing literature and identifying appropriate biochemical markers in predicting progression of acute pancreatitis, the ideal predictor would be a combination of biochemical, clinical and contemporary organ dysfunction scoring systems. Early prediction of disease progression however, is important in the better management of the disease. The pathophysiological changes of acinar cell injury and death are the earliest events that occur in acute pancreatitis. Identification of potential pharmacological interventions offered through valuable insight in to experimental and clinical acute pancreatitis may lead on to the development of various natural and synthetic potential disease modifiers. Green Tea Extracts (GTE) consumed in many parts of the world has been examined as a potential therapeutic medication. Experimental results have demonstrated the effect of GTE on the oxidative pathway significantly ameliorating the effects of pancreatic injury. The various green tea catechins especially Epigallocatechin-3- gallate (EGCG) can perhaps be useful lead compounds for new drug discovery. With no specific targeted therapy for severe acute pancreatitis at present, various medications have been tested. The possibility of targeting initial acinar cell injury may not be a feasible option as patient presentation and management would usually be after this phase. As the disease progresses, severe acute pancreatitis is characterised by inflammation and necrosis. The hypothesis of preserving pancreatic parenchymal microvascular patency and thus ameliorating pancreatic injury through the early administration of recombinant human Activated Protein C (rhAPC) has identified a potential treatment for acute pancreatitis. rhAPC converted from its inactive precursor, protein C, by thrombin acts through fibrinolysis and inhibition of thrombosis. Studies on rhAPC in experimental acute pancreatitis examined the modulation of rhAPC on inflammatory markers, morphology, microvascular thrombosis and apoptosis. The encouraging results from initial experimental work helped set up the Phase 2 clinical trial of administering rhAPC early on in severe acute pancreatitis. Prior to taking this significant step from bench to bed side, the variation in functional protein C levels with the severity of the disease was examined as a precursor to the Phase 2 trial.
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Storage and allogeneic transplantation of peripheral nerve using a green tea polyphenol solution in a canine model / ポリフェノール処理による末梢神経の保存と同種移植に関する犬モデルの研究

Nakayama, Ken 25 January 2016 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第12980号 / 論医博第2106号 / 新制||医||1012(附属図書館) / 32450 / (主査)教授 髙橋 良輔, 教授 鈴木 茂彦, 教授 高橋 淳 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Dietary Green Tea to Attenuate Metabolic Endotoxemia-Associated Inflammation Along the Gut-Liver Axis

Sasaki, Geoffrey Y. January 2020 (has links)
No description available.

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