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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.
81

Imobilização de pepsina em membranas liofilizadas de quitosana e O-carboximetilquitosana / Pepsin immobilization into lyophilized chitosan and O-carboxymethilchitosan membranes

Karine Gargioni Pereira Correa de Mello 23 November 2009 (has links)
Enzimas são proteínas utilizadas em processos tecnológicos diversos. Estas enzimas dependendo do tipo e grau de pureza são geralmente caras. Comumente as enzimas exigem controle contínuo do processo no que se refere à temperatura, pH, agitação, entre outros, e após o uso são descartadas, o que torna o custo do processo mais elevado. Em decorrência disto, a imobilização de enzimas em suportes insolúveis e inertes, vem sendo proposta com resultados promissores de manutenção e até mesmo aumento da atividade enzimática, resistência mecânica, térmica e de pH, bem como por apresentar maior facilidade de remoção da enzima do sistema e possibilitar sua reutilização. Por causa disto, diferentes tipos de suportes vêem sendo estudados, dentre estes, os materiais poliméricos, tem recebido atenção especial. A quitosana é um polímero natural, biocompatível, biodegradável e atóxico. É obtida de fontes renováveis provenientes do descarte de cascas de crustáceos da indústria de alimentos, o que constitui um fator ambiental importante atualmente. Neste trabalho a enzima pepsina foi imobilizada em membranas liofilizadas de quitosana e O-carboximetilquitosana reticuladas ou não com glutaraldeído. A pepsina imobilizada na membrana de quitosana reticulada com glutaraldeído manteve sua atividade enzimática e o suporte apresentou propriedades físico-químicas de resistência a solubilização em pH ácido, o qual é necessário para atividade da pepsina. O processo de liofilização preservou a estrutura do suporte e não comprometeu a atividade enzimática. Demonstrando que o processo de liofilização é viável para secagem e incorporação de enzimas. / Enzymes are proteins used in a wide variety of biotechnological processes. Commonly, enzymes require stringent conditions, such as a particular pH, temperature, stirring, etc. In chemical and biochemical reactions, purified enzymes can be rather costly and additionally, must be discarded after each use, which is still less economical. As a result of this, enzyme immobilization on insoluble and inert supports has been studied as a manner to overcome these problems and optimize enzymes use. Promising results of greater immobilized enzyme activity and stability over a broader range of pH and temperature have been reported. As well, immobilized enzymes can be easily removed from the system and reused. Various materials have been employed as enzymes supports, among then, the polymers have received special attention. Chitosan is a natural polymer that presents biocompatibility, biodegradability and nontoxicity. Chitosan is obtained from crustacean shell wastes discarded by the food industry, and recover this material constitutes an important environmental factor nowadays. In this work the enzyme pepsin was immobilized on freezedried chitosan and O-Carboxymethylchitosan membranes crosslinked or not with glutaraldehyde. Pepsin immobilized on chitosan membrane crosslinked with glutaraldehyde maintained its enzymatic activity and the polymer support provided physicochemical properties such resistance to dissolution in acid pH. Acid pH is required for pepsin activity. The freeze-drying process preserved the support structure and did not compromise the enzymatic activity. Demonstrating that, freeze drying process, is viable for drying and enzymes incorporation.
82

Periodontite experimental como fator de risco na potencialização dos efeitos do imobilismo / Experimental periodontitis as a risk factor in potentializing the effects of immobility

Leite, Marcela Aparecida 25 January 2017 (has links)
Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2017-11-27T18:31:17Z No. of bitstreams: 2 MARCELA LEITE2017.pdf: 2527004 bytes, checksum: 37310bebca45bcc15d56cfda1b505434 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-11-27T18:31:17Z (GMT). No. of bitstreams: 2 MARCELA LEITE2017.pdf: 2527004 bytes, checksum: 37310bebca45bcc15d56cfda1b505434 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-01-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Objective: To evaluate whether periodontal disease, through systemic inflammation, can potentiates the deleterious effects of immobilization of the skeletal striated muscle, contributing to the development of muscle atrophy due to disuse. Methods: Forty Wistar rats were divided into four groups: 1) Control Group (CG), 2) Periodontal Disease (GPD) 3) Immobilized (IG) and 4) Immobilized with Periodontal Disease (IPDG). Periodontal disease was induced for 30 days, with ligature method, and the immobilization of the right pelvic limb was performed with cast bandage for 15 days. Prior to euthanasia, the nociceptive threshold and muscular grasping force were evaluated. Afterwards, the soleus muscle was dissected and processed for sarcomere counting and morphological and morphometric analysis. For analysis of the data, the one-way ANOVA followed by the Tukey post test, with p < 0.05. Results: The IG and IPDG groups presented lower muscle weight, lower muscular grip strength and less number of sarcomeres compared to CG. The PDG showed reduction of muscle strength and nociceptive threshold after 15 days of periodontal disease and increase of connective tissue compared to CG. The IPDG presented lower muscle length and nociceptive threshold compared to the other groups. The IG presented a reduction in the cross-sectional area and a smaller diameter, an increase in the number of nuclei and a nucleus/fiber ratio, a decrease in the number of capillaries and a capillary/fiber ratio, with an increase in connective tissue. In the IPDG group, there were significant results for increased nucleus/fiber ratio, decreased capillaries and increased connective tissue when compared to the IG group. The IPDG group presented greater muscle tissue degeneration and increased inflammatory cells when compared to the other groups. Conclusion: Periodontal disease potentiated the deleterious effects of immobilization of the skeletal striated muscle, through intense destruction of muscle tissue, with significant increase of connective tissue, nucleus/fiber ratio and inflammatory infiltrate, significant reduction of vascularization and reduction of muscle length, with consequent reduction of muscle strength and nociceptive threshold. / Objetivo: Avaliar se a doença periodontal, por meio da inflamação sistêmica, potencializa os efeitos deletérios da imobilização do músculo estriado esquelético, colaborando para o desenvolvimento da atrofia muscular por desuso. Metodologia: Foram utilizados 40 ratos Wistar, divididos em quatro grupos: 1) Grupo Controle (GC); 2) Doença Periodontal (GDP); 3) Imobilizado (GI); 4) Doença Periodontal Imobilizado (GDPI). A doença periodontal foi induzida pelo método de ligadura, durante 30 dias e a imobilização do membro pélvico direito foi realizada com atadura gessada, por 15 dias. Antes da eutanásia, foram avaliados o limiar nociceptivo e força muscular de preensão. Após, o músculo sóleo foi dissecado e processado para contagem de sarcômeros e análise morfológica e morfométrica. Para análise dos dados, foi utilizado o teste ANOVA de uma via seguida do post test Tukey, com p<0,05. Resultados: Os grupos GI e GDPI apresentaram menor peso muscular, força muscular de preensão e número de sarcômeros comparados ao GC. O GDP apresentou redução da força muscular e do limiar nociceptivo após 15 dias de doença periodontal e aumento de tecido conjuntivo comparado ao GC. O GDPI apresentou menor comprimento muscular e limiar nociceptivo comparados aos demais grupos. O GI apresentou redução da área de secção transversa e menor diâmetro, aumento no número de núcleos e razão núcleo/fibra, diminuição no número de capilares e razão capilar/fibra, com aumento de tecido conjuntivo. No grupo GDPI, houve resultados significativos para aumento da razão núcleo/fibra, diminuição de capilares e aumento de tecido conjuntivo quando comparado ao grupo GI. O grupo GDPI apresentou maior degeneração do tecido muscular e aumento de células inflamatórias quando comparado aos outros grupos. Conclusão: A doença periodontal potencializou os efeitos deletérios da imobilização do músculo estriado esquelético, por meio da intensa destruição do tecido muscular, com significativo aumento do tecido conjuntivo, da razão núcleo/fibra e infiltrado inflamatório, significativa diminuição da vascularização e redução do comprimento muscular, com consequente redução da força muscular e limiar nociceptivo.
83

Alterações musculoesqueléticas em camundongos obesos e desnutridos após protocolo de imobilização articular do membro pélvico unilateral / Musculoskeletal changes in obese and malnourished mice after the protocol of hindlimb joint immobilization

Rissi, Renato, 1988- 26 August 2018 (has links)
Orientador: Evanisi Teresa Palomari / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T00:31:52Z (GMT). No. of bitstreams: 1 Rissi_Renato_M.pdf: 1479367 bytes, checksum: e178a8d14769b59ec03814960ceef145 (MD5) Previous issue date: 2014 / Resumo: No âmbito da ortopedia, a imobilização articular é um recurso terapêutico eficiente e amplamente utilizado na prática clínica. Apesar de seu uso ser indispensável no tratamento de doenças álgicas ou fraturas, a imobilização ocasiona no paciente uma limitação física temporária de suas habilidades, podendo influenciar em sua locomoção e em suas atividades do cotidiano. A obesidade interfere muitas vezes na relação do hormônio insulina com os mecanismos de síntese e degradação proteica nos músculos. Considerando que a insulina exerce papel fundamental facilitando a síntese e inibindo a proteólise, os pacientes obesos, podem apresentar um balanço negativo no que se diz respeito à formação e degradação da massa muscular em virtude das desordens que estes pacientes geralmente apresentam no perfil insulinêmico. O tecido muscular é a reserva mais importante de proteína disponível no organismo, porém, este tecido se encontra consideravelmente reduzido nos casos de desnutrição proteica. Durante o jejum parcial ou total, a proteína corporal é destruída para proporcionar aminoácidos ao organismo, traduzindo-se desta forma em uma perda de massa corporal total. Quando consideramos a obesidade e a desnutrição proteica, associadas a um paciente imobilizado, a interação dessas condições podem vir a potencializar os prejuízos musculoesqueléticos do paciente. O objetivo deste estudo foi verificar experimentalmente se a condição de imobilização articular potencializa as alterações musculoesqueléticas em animais obesos e desnutridos. Para tal, 60 camundongos da linhagem C57BL6 foram utilizados e divididos em quatro grupos: Controle (GC), Controle Imobilizado (GCI), Obeso Imobilizado (GOI), Desnutrido Imobilizado (GDI). A imobilização articular foi realizada utilizando-se um modelo com esparadrapo/gesso adaptado para uso em camundongos. Os animais permaneceram imobilizados durante 14 dias. A obesidade e a desnutrição proteica foram desenvolvidas por meio de ingestão alimentar de dieta específica para cada grupo. Realizou-se análise da atividade locomotora; quantificação sérica da enzima creatina quinase; análise histomorfométrica da tíbia e dos músculos gastrocnêmio e tibial anterior; determinação do conteúdo de glicogênio intramuscular e zimografia das metaloproteinases (2 e 9). Como resultado, verificou-se a redução da atividade locomotora noturna nos animais imobilizados em relação ao GC; aumento dos níveis séricos da enzima CK nos animais imobilizados em relação ao GC; redução na área e no diâmetro das fibras musculares do gastrocnêmio e tibial anterior nos grupos imobilizados em relação ao GC; diminuição do conteúdo de glicogênio intramuscular no GDI em relação ao GCI; aumento da expressão das metaloproteinases 2 e 9 nos grupos imobilizados em relação ao GC. Portanto, podemos concluir que o protocolo de imobilização articular utilizado é capaz de gerar atrofia musculoesquelética nos animais. Já no caso da interação entre as condições de obesidade/imobilização e desnutrição/imobilização, o tecido musculoesquelético apresenta acréscimo na atrofia, revelando elevado prejuízo muscular nessas condições / Abstract: Within orthopedics, joint immobilization is an effective therapeutic tool and widely used in clinical practice. Although their use is essential in the treatment of painful diseases or fractures, the patient immobilization causes a temporary physical limitation of their abilities and may influence its locomotion and in their daily activities. Obesity often interferes to the hormone insulin in relation with the mechanisms of protein synthesis and degradation in muscle. Considering that insulin plays a key role in facilitating the synthesis and inhibiting proteolysis, obese patients may have a negative balance as regards the formation and degradation of muscle mass because of disorders in these patients insulinemic profile. Muscle tissue is the most important reserve available protein in the body, however, this tissue is considerably reduced in cases of malnutrition. During the partial or total fasting, the body protein is destroyed to provide amino acids to the body, thus translating into a loss of total body mass. When we consider obesity and protein malnutrition associated with an immobilized patient, the interaction of clinical conditions can come to enhance the patient's musculoskeletal damage. The aim of this study was to verify experimentally if the condition of joint immobilization enhances musculoskeletal changes in obese and malnourished animals. To this end, 60 mice C57BL6 were used and divided into four groups: Control (CG), Immobilized Control (ICG), Immobilized obese (IOG), Immobilized Malnourished (IMG). The joint immobilization was performed using a model with tape / plaster adapted for use in mice. The animals remained immobilized for 14 days. Obesity and protein malnutrition were developed by means of specific diets food intake for each group. We performed analysis of locomotor activity; quantification of serum CK; histomorphometric analysis of the tibia and the gastrocnemius and tibialis anterior muscles; determining the content of intramuscular glycogen; zymography of the metalloproteinases (2 and 9). As a result, we found reduction in nocturnal locomotor activity in immobilized animals relative to CG; increased serum levels of creatine kinase in the immobilized animals relative to CG; reduction in the area and diameter of the muscle fibers of the gastrocnemius and tibialis anterior in groups immobilized relative to CG; decreased content of intramuscular glycogen in the group IMG relative to ICG; increased expression of metalloproteinases 2 and 9 in groups immobilized relative to CG. Therefore, we conclude that the joint immobilization protocol used is able to generate skeletal muscle atrophy in animals. In the case of the interaction between the conditions of obesity / immobilization and malnutrition / immobilization, tissue musculoskeletal presents increase in atrophy, revealing high muscle injury in these conditions / Mestrado / Anatomia / Mestre em Biologia Celular e Estrutural
84

Conversão de sacarose em isomaltulose e trealulose utilizando-se células de Serratia plymuthica ATCC 15928 livres e imobilizadas em diferentes matrizes com adição de transglutaminase / Conversion of isomaltulose and trehalulose from sucrose by Serratia plymuthicacells free and immobilised using transglutaminase

Carvalho, Priscila Hoffmann, 1983- 23 August 2018 (has links)
Orientador: Hélia Harumi Sato / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-23T16:00:04Z (GMT). No. of bitstreams: 1 Carvalho_PriscilaHoffmann_D.pdf: 4102242 bytes, checksum: 1496382da70a395d87d5c8536317d42d (MD5) Previous issue date: 2013 / Resumo: A isomaltulose e a trealulose são dissacarídeos isômeros estruturais, que podem ser obtidos a partir da sacarose utilizando-se glicosiltransferase bacteriana. Esses dissacarídeos são considerados açúcares alternativos de grande potencial para uso nas indústrias de alimentos e farmacêutica porque são hidrolisados e absorvidos mais lentamente e apresentam baixo potencial cariogênico comparado com a sacarose. Foi estudada a imobilização de células de Serratia plymuthica ATCC 15928, produtora de glicosiltransferase por gelificação iônica em gel alginato contendo transglutaminase (TG) e também a utilização de células livres para a conversão de sacarose em isomaltulose e trealulose. Utilizando-se células livres de Serratia plymuthica ATCC 15928 foi obtido 70% de conversão em isomaltulose e 8% de trealulose a 25°C por 10 bateladas de 15 minutos, a partir de solução de sacarose 30%. Entre as cinco amostras de alginato de sódio testadas, para a imobilização das células de S. plymuthica ATCC 15928 com e sem adição de TG, foram obtidos melhores resultados (médio de três bateladas) de conversão de sacarose (37,4% de isomaltulose) utilizando o alginato de sódio B, de alta viscosidade (14.000cP Sigma ¿ A 7128) em presença de TG. Nas condições estudadas (1,7% de alginato de sódio, 30% de massa celular úmida, solução de cloreto de sódio 0,2Mol/L, 2% de TG e 35% de sacarose) também houve maior facilidade de formação de grânulos uniformes. A presença de TG como agente de reticulação na matriz de imobilização melhorou a estabilidade de conversão por três bateladas onde observou-se resultado médio 27% maior com relação a matriz com o mesmo tipo de alginato (B) em ausência de TG. A composição da matriz de imobilização com adição de TG foi otimizada por metodologia de planejamento experimental, assim como a adição de gelatina como fonte de proteína adicional para promoção de ligações cruzadas catalisadas pela TG. Os melhores resultados de conversão de sacarose (solução 35%) em isomaltulose (72,66% de isomaltulose e 8% de trealulose em 4 bateladas de 24horas) foram obtidos utilizando-se matriz de polissacarídeo-proteína composto de 1,7% de alginato de sódio 14.000cP (Sigma®-A7128), 0,25mol/L de CaCl2, 0,5% de gelatina, 3,5% de TG e concentração de massa celular úmida superior a 35% (m:v). Verificou-se que a adição de ALMP na matriz de alginato de cálcio-gelatina-TG para imobilização de S. plymuthica, testada por planejamentos experimentais seqüenciais, não aumentou a estabilidade da taxa de conversão de sacarose em isomaltulose quando comparada com as células imobilizadas em matriz de alginato de cálcio-gelatina-TG. Em processo contínuo utilizando-se coluna empacotada com células de S. plymuthica imobilizadas em matriz otimizada e descrita acima, foi obtida taxa de conversão média de 64% de sacarose em isomaltulose durante 200 horas de processo, equivalente a 0,27g de isomaltulose/g de células imobilizadas/hora em coluna a 25°C e fluxo de substrato (35% de sacarose) 0,2mL/min / Abstract: The isomaltulose and trehalulose are disaccharides and structural isomers, which can be obtained from sucrose using bacterial glycosyltransferase. These disaccharide are considered alternative sugars with great potential for use in the food and pharmaceutical industries because they are hydrolyzed and absorbed more slowly and have a low cariogenic potential compared with sucrose. The conversion of sucrose to isomaltulose and trehalulose was estudied using immobilized and free cells of Serratia plymuthica ATCC 15928. The cells were immobilized by ionic gelation in alginate gel containing transglutaminase. Using free cells of Serratia plymuthica ATCC 15928 was obtained 70% isomaltulose conversion and 8% trehalulose conversion at 25° C in 10 batches of 15 minutes from a 30% sucrose solution. Among the five samples of sodium alginate tested for S. plymuthica ATCC 15928 cells immobilization, with or without the addition of TG, the best results (average of three batches) were obtained using sodium alginate B, high viscosity (14.000cP Sigma - A 7128) in the presence of TG, leading to 37.4% isomaltulose conversion from sucrose. In the studied conditions (1.7% sodium alginate, 30% wet cell mass solution of sodium chloride 0.2 Mol/L, 2% TG, 35% sucrose) was also easier to form uniform granules. The presence of TG as a crosslinking agent in the immobilization matrix improved the stability during three batches, resulting in an 27% higher average conversion with respect to a same type of alginate (B) matrix in absence of TG. Immobilization matrix compositions with addition of TG was optimized by experimental design methodology, as well as the addition of gelatin as a protein source for promoting additional crosslinking catalyzed by TG. The best results conversion of sucrose (35% solution) into isomaltulose (72.66% of isomaltulose and 8% of trehalulose in 4 batches of 24 hours) were obtained using proteinpolysaccharide matrix composed of 1.7% alginate 14.000cP sodium (Sigma® A7128), 0.25 Mol/L CaCl2, 0.5% gelatin, 3.5% TG, and wet cell mass concentration of 35% (w:v). It has been found that the addition of ALMP (amidated low methoxyl pectin) into the calcium alginate-gelatin-TG matrix for immobilization of S. plymuthica, tested by sequential experimental design, do not increase the stability of sucrose to isomaltulose conversions rate when compared with cells immobilized in calcium alginate -gelatin-TG matrix. In continuous process using a packed column with S. plymuthica cell's immobilized in the optimized matrix described above, it was obtained an average conversion rate of 64% sucrose to isomaltulose during a 200 hours process, equivalent to 0.27g isomaltulose per gram of immobilized cell per hour, in a column at 25° C and using flow substrate (35% sucrose) of 0.2 mL / min / Doutorado / Ciência de Alimentos / Doutora em Ciência de Alimentos
85

Imobilização da tanase de Paecilomyces variotii e ação em reações de hidrólise e síntese / Immobilization of tannase from Pecilomyces variotii and reactions of hydrolysis and synthesis

Schons, Patricia Fernanda 06 June 2012 (has links)
Orientador: Gabriela Alves Macedo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-20T10:15:17Z (GMT). No. of bitstreams: 1 Schons_PatriciaFernanda_D.pdf: 7426090 bytes, checksum: 313de43e28f0e8dfd168987a56f6a2c1 (MD5) Previous issue date: 2012 / Resumo: Tanino acil hidrolase (TAH) conhecida como tanase (EC 3.1.1.20) é uma enzima que hidrolisa ésteres e taninos hidrolisáveis produzindo glicose e ácido gálico quando o meio reacional for polar. No entanto, a literatura indica sua capacidade de esterificar também ésteres de ácidos gálico em meio orgânico. Nosso grupo de pesquisa isolou um fungo, Paecilomyces variotii, produtor de tanase no ano de 2005 e desde então vem desenvolvendo estudos de produção, purificação, caracterização e aplicações desta enzima. Dando continuidade à linha de pesquisa, o objetivo deste trabalho foi estudar um processo de imobilização da tanase de Paecilomyces variotii empregando diferentes suportes e técnicas. Foram avaliados os parâmetros do processo de imobilização, a tanase livre e imobilizada foi caracterizada bioquimicamente ainda foi investigada a quimioseletividade da tanase imobilizada e livre para reações de síntese. A tanase foi imobilizada pelo método de adsorção em alumina, Amberlite, Accurel e celite; por ligação covalente em amberlite e Dowex ativados com polietilenoimina e glutaraldeído e em sílica, accurel e celite ativados com 3-aminopropiltrietoxisilano e glutaraldeído e por gelificação iônica em alginato de sódio, alginato de alga marrom, carragena, quitosana, pectina e goma gelana. A tanase imobilizada foi avaliada quanto a porcentagem de atividade enzimática e porcentagem de eficiência de imobilização. O processo de imobilização de tanase em alginato de sódio foi otimizado empregando a ferramenta de planejamento de experimentos. A tanase imobilizada em alginato na condição otimizada, foi avaliada quanto ao reuso e caracterizada bioquimicamente quanto ao pH e temperatura ótimos de atividade e de estabilidade e quanto a atividade frente a inibidores. Em adição ao processo de imobilização, foi avaliado o efeito do emprego de reticulantes: genipina, glutaraldeído, transglutaminase Activa® e transglutaminase de Streptomyces sp. CBMAI 837. As cápsulas obtidas foram avaliadas quanto à atividade enzimática, eficiência de imobilização e sua morfologia foi avaliada por microscopia eletrônica de varredura. Dentre os suportes empregados para imobilização de tanase por adsorção, ligação covalente e gelificação iônica obteve-se maior porcentagem de atividade enzimática utilizando os suportes celite, sílica ativada com 3-aminopropiltrietoxisilano e glutaraldeído e alginato de sódio, respectivamente. A condição otimizada para a imobilização de tanase em alginato de sódio foi com 3,6% de alginato de sódio, cloreto de cálcio 0,1M, 3,6mg de tanase/mL de alginato e 6h de cura. Após o processo de otimização a tanase aumentou 35 vezes sua atividade enzimática. A tanase imobilizada em alginato de sódio nas condições otimizadas pode ser reutilizadas por até 5X mantendo 60% de sua atividade catalítica, as cápsulas apresentaram maior estabilidade quanto ao pH, temperatura e inibidores comparando com a tanase livre. Por fim, avaliouse a capacidade da tanase livre e imobilizada em sintetizar ésteres de ácido gálico. A tanase livre mostrou-se efetiva na síntese de galatos, especialmente, propilgalato com porcentagem de esterificação de 65%, já com a tanase imobilizada em alginato de sódio somente 8% de esterificação do propilgalato foi observado / Abstract: Tannin acyl hydrolase (TAH) known as tannase (EC 3.1.1.20) is an enzyme that hydrolyzes esters of hydrolysable tannins producing gallic acid and glucose as the reaction medium is polar. However, the literature indicates their ability to produce also gallic acid esters in organic media. Our research group has isolated a fungus, Paecilomyces variotii, tannase producer in 2005 and since then has been conducting studies of production, purification, characterization and applications of this enzyme. Continuing the research, the objective of this work was study a process to immobilize tannase from Paecilomyces variotii using different supports and techniques. Were evaluated the parameters of the immobilization process, free and immobilized tannase were characterized biochemically and yet been investigated quimioseletivity of tannase immobilized and free for synthesis reactions. Tannase was immobilized by adsorption onto alumina, Amberlite, Accurel and celite, by covalent binding in Amberlite and Dowex activated with polyethyleneimine and glutaraldehyde on silica, celite and Accurel activated with glutaraldehyde and 3-aminopropyltriethoxysilane and ionic gelation by sodium alginate, alginate from brown seaweed, carrageenan, chitosan, pectin and gellan gum. The immobilized tannase was evaluated as the percentage of enzyme activity and percentage of immobilization efficiency. The immobilization process of tannase in sodium alginate was optimized using the experimental design method. After the optimization process the tannase immobilized in alginate was evaluated for reuse and characterized biochemically for pH and temperature optima for activity and stability and the activity against inhibitors. In addition to the immobilization process, we evaluated the effect of the use of cross-linking: genipin, glutaraldehyde, Transglutaminase Activa ® and the transglutaminase from Streptomyces sp. CBMAI 837. The capsules obtained were evaluated for percentage of enzymatic activity, percentage of immobilization efficiency and their morphology was studied by scanning electron microscopy. Among the carriers used for immobilization of tannase by adsorption, covalent and ionic gelation has been a higher percentage of enzyme activity using the supports celite, silica activated with glutaraldehyde and 3-aminopropyltriethoxysilane and sodium alginate, respectively. The optimal conditions for immobilization of tannase in sodium alginate were 3.6% sodium alginate, calcium chloride 0.1 M, 3.6 mg of tannase / mL alginate and 6h of cure. After the optimization process, the tannase activity increased by 35 times. The tannase immobilized on sodium alginate in the optimized conditions can be reused up to 5X keeping 60% of its catalytic activity, the capsules showed greater stability for pH, temperature and inhibitors compared with free tannase. Finally, we evaluated the ability of free and immobilized tannase in synthesizing esters of gallic acid. The free tannase proved to be effective in the synthesis of gallates, especially propyl gallate with a percentage of esterification of 65%, with the immobilized tannase in sodium alginate was observed only 8% of propyl gallate esterification / Doutorado / Ciência de Alimentos / Doutor em Ciência de Alimentos
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Novas fases estacionarias para CLAE preparadas por imobilização termica de PMODS sobre diferentes suportes de silica / New stationary phases for HPLC prepared by thermal immobilization of PMODS on different on different types of silica supports

Chaudhry, Zahra Fazal 28 February 2005 (has links)
Orientador: Carol Hollingworth Collins / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-04T16:24:19Z (GMT). No. of bitstreams: 1 Chaudhry_ZahraFazal_D.pdf: 3872022 bytes, checksum: b24a0aac0711390db05a94078e2b747f (MD5) Previous issue date: 2005 / Resumo: As fases estacionárias (FE) são consideradas uma das peças chave na técnica de Cromatografia Líquida de Alta Eficiência (CLAE). Neste trabalho foram avaliadas FE preparadas a partir de seis diferentes sílicas utilizadas como suporte para a imobilização do polímero poli(metiloctadecilsiloxano) (PMODS). Três destes suportes são sílicas com poros grandes, que atualmente apresentam grande aplicação em separações de macromoléculas. O primeiro passo para os testes cromatográficos das FE desenvolvidas foi o preparo de uma nova mistura padrão. A partir dela foi possível avaliar comparativamente as principais características das novas FE como a eficiência, a hidrofobicidade, a capacidade de separação de compostos de estruturas espaciais similares além de compostos de diferentes polaridades. Durante o estudo da metodologia de preparo das FE, definiu-se o tratamento térmico como a técnica utilizada para a imobilização do polímero sobre o suporte. Análises de ressonância magnética nuclear mostraram que, através desta metodologia, o polímero é adsorvido sobre a superficie de sílica formando uma monocamada estável distribuída de forma altamente favorável ao processo de transferência de massa entre a FE e a fase móvel (FM). Os suportes de sílica foram divididos em dois grupos, de acordo com suas caracteristicas estruturais, e em cada um dos grupos, foi realizada a otimização de variáveis como a carga de polimero adsorvido na superficie do suporte, a temperatura ideal de imobilização térmica e o tempo de imobilização. Os resultados obtidos através de testes cromatográficos mostraram que a variável tempo de imobilização é extremamente relevante no desempenho e eficiência das FE devendo ser ajustada seguindo as caracteristicas estruturais do suporte. Isto se deve principalmente à maneira como se organizam as cadeias do PMODS dentro dos poros da sílica e sobre sua superficie. Esta técnica de imobilização por tratamento térmico produziu FE de grande eficiência, capazes de realizar separações similares às observadas em colunas cromatográficas comerciais, como foi comprovado pelos resultados de separações de fármacos e pesticidas avaliados neste trabalho. / Abstract: Stationary phases (SP) are an important component in HPLC technique. ln this work, SP with the polymer poly(methil octadecylsiloxane) (PMODS) immobilized onto six different silica surfaces were evaluated. Three of these supports were wide pore silicas that offer ample application in macromolecule separations. The first step for the chromatograprnc tests was to develop a new test mixture of analytes. This test rnade possible comparative evaluations of the to main characteristics of the newly prepared SP, such as efficiency, hidrofobicity and the separation capacity of compounds with different polarities. During the study of SP preparation methodology, thermal treatments were defined as the technique for immobilization of PMODS onto the silica supports. Analyses of nuclear magnetic resonance demonstrated that, through this methodology, the polymer is sorved on the silica surface forming a distributed stable monolayer, leading to a highly favorable mass transfer process between SP and mobile phase (MP). The silica supports were divided into two groups according to their structural characteristics. In each group, optimization of variables, such as polymer load and the ideal temperature and time of thermal immobilization, was performed. The chromatographic results showed that time of immobilization is an extremely important variable for SP efficiency and that it should be adjusted according to the structural characteristics of the support. This is due mainly to the manner in which PMODS chains are organized inside the pores of silica surface. The proposed technique of immobilization by thermal treatment produced high efliciency SP that offer potential for applications in chemical separations similar to thase observed with commercially available columns, as showed by separations of pharmaceutical compounds and herbicides with these new chromatographic columns. / Doutorado / Quimica Analitica / Doutor em Ciências
87

Nanolithography with molecules using advanced scanning probe microscopy methods

Jirlén, Johan January 2018 (has links)
The possibilities of novel catalytic scanning probe lithography (cSPL) on starch using α-amylase was investigated. For this thin homogeneous layers of starch with good coverage were prepared by spin coating a starch solution on a silicon base. Amylase immobilized to an atomic force microscopy (AFM) cantilever tip were prepared and dragged along a spin coated starch surface. This after verifying the enzyme immobilization method using (3-Aminopropyl)triethoxysilane (APTES) on a silicon surface. In addition an unmodified cantilever tip were dipped in amylase solution and were dragged along a starch surface to investigate possibilities of dip-pen nanolithography (DPN). The preliminary experiments with AFM based enzymatic lithography were promising but non-conclusive. There are still many parameters not fully explored such as water availability, activity and reach of the amylase, speed of the enzymatic process and difference in structure between the starch and the shorter saccharides that are left after the hydrolysis
88

Efficacy of tarsal immobilization to alleviate Achilles tendon strain in vivo – direct measurements via a differential variable reluctance transducer™ (DVRT) strain gauge in a canine model

Lister, Stephanie A. January 1900 (has links)
Master of Science / Department of Clinical Sciences / Walter C. Renberg / Objective: To measure strain in vivo in the calcanean tendon during trotting in canines, and to compare to strain present after tibiotarsal immobilization. Animals: 6 canines Procedures: A Differential Variable Reluctance Transducer[superscript]TM (DVRT®) strain gauge was surgically implanted on the common gastrocnemius tendon. Surface EMG, % strain, and ground reaction forces were measured prior to intervention and after immobilization. Peak vertical force (Fz), vertical impulse, initial, maximum and final strain, and peak-to-peak EMG amplitude were recorded. Data was analyzed using repeated measures analysis of variance and paired t-tests (p[equal to or less than]0.05). Results: Timing of strain data correlated closely to the hind limb footstrike and EMG activity in all dogs. Maximum tendon strain occurred simultaneous with peak Fz. Continued muscle contraction was evident after immobilization. There was no statistical difference in maximum strain after immobilization compared to normal motion. Minimum strain, both at the beginning and end of the strain curve, was significantly decreased with the immobilized state compared to non-immobilized joints. Conclusions and Clinical Relevance: Tibiotarsal immobilization did not eliminate calcaneal tendon strain during weight bearing. Decreased isometric muscle contraction during swing phase of the gait would account for smaller minimum strain in immobilized joints. Immobilization is frequently applied after Achilles tendon rupture to alleviate strain and force on the sutured repair, with possible complications due to the immobilization method. Direct correlation of strain with tendon force was not made in this study. This would be an important factor before adjusting current treatment recommendations.
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Mise en oeuvre des surfaces spécifiques en vue de la détection de bactéries pathogènes par diffusion Raman / Elaboration of functionalized surfaces in the aim of pathogenic detection by Raman scattering

Kengne-Momo, Rosine Pélagie 06 May 2011 (has links)
L’objectif de cette thèse est de synthétiser de nouvelles surfaces spécifiques nécessaires à l’immobilisation des biomolécules ; visant à développer à terme un biocapteur pour la détection de pathogènes en industrie agroalimentaire. Cette nouvelle procédure de fonctionnalisation de surface consiste d’une part à greffer des molécules organiques sur un substrat métallique à partir d’une réaction électrochimique et d’autre part de synthétiser un monomère photopolymérisable sur tout type de surface. Ces surfaces sont enfin utilisées pour immobiliser les biomolécules. Ce procédé ainsi développé permet d’éliminer les multiples étapes, l’utilisation excessive de réactifs observés dans les protocoles classiques de fonctionnalisation de surface pour la capture de microorganismes. Deux stratégies de fonctionnalisation ont été investiguées : la polymérisation sur une plaque de platine et le dépôt de monocouche sur une surface d’or. La fonctionnalisation de surfaces ainsi que l’immobilisation de biomolécules ont été caractérisées par la spectroscopie Raman, la microbalance à cristal de quartz, la microscopie à force atomique (AFM) pour le premier et en plus la microscopie à fluorescence pour le second. Les résultats de la fonctionnalisation de surfaces par dépôt de polymère ont montré, une déstabilisation du polymère en présence de l’eau. Afin d’optimiser la synthèse, nous avons travaillé en milieu inerte, sous alumine activée. De plus, on note une large couverture de la zone spectrale des biomolécules par les signaux du polymère ; Pour le dépôt de monocouche, l’on a obtenu une surface très réactive, homogène. La diffusion Raman est la principale technique de caractérisation utilisée. Elle présente l'avantage d'être une méthode de caractérisation physico-chimique non destructive et non invasive. Longtemps délaissée dans les sciences du vivant, cette méthode apparaît maintenant particulièrement prometteuse grâce à un développement récent de spectromètres intégrés performants. La diffusion Raman sur la monocouche déposée montre une intensité accrue des signaux par l’utilisation de la surface d’or et un spectre plus dégagé conduisant à l’identification aisée des biomolécules après fixation. Elle permet non seulement d’identifier les bandes de vibrations de chaque groupement mais aussi la conformation des structures. Les résultats d’immobilisation ont montré que l’accroche des biomolécules sur les surfaces fonctionnalisées était spécifique. La fonctionnalisation de surface d’or par dépôt de monocouche constitue finalement une technique très rapide à mettre en œuvre, peu coûteuse permettant d’ancrer efficacement les biomolécules et peut être utilisée pour diverses applications. La synthèse du monomère photopolymérisable a été abordée et est en cours d’investigation. / In food processing industry, detecting bacteria or viruses is crucial. Nowadays, it can be achieved with microbiological tests but, it requires several days. The objective of the project was to synthesize new specific surfaces capable of biomolecules immobilization in order to develop a biosensor for the detection of various pathogenics in food-processing industry. This new procedure of surface functionalisation consists on one hand in anchoring organic molecules on a metallic substrate by an electrochemical reaction and on the other hand to synthesize a photocrosslinkable monomer on every type of surface. These surfaces are finally used to immobilize biomolecules. Two strategies of surface functionalisation were investigated: the polymerization on a platinium surface and the deposition of monolayer on a gold surface. Both processes were characterized by spectroscopy Raman, Quartz Crystal Microbalance, Atomic Force Microscopy and Fluorescence Microscopy. The results of the functionalisation of surfaces by deposition of polymer showed a destabilization of the polymer in presence of water. To optimize the synthesis, we worked in sluggish middle, under activated alumina. Furthermore, we noted a wide coverage of the spectral zone of biomolecules by the signals of the polymer; For the monolayer deposition, we obtained a very reactive and homogeneous surface. The Raman spectroscopy was the main technique used to the characterization. It presented the advantage to be a non-destructive and non invasive physico-chemical method. This method seemed now particularly promising due to a recent development of successful integrated spectrometers. Raman Spectroscopy showed an enhanced intensity of the signals by the use of the gold surface and a more clear spectrum well-to-do identification of biomolecules after binding. It allowed not only the identification of the bands of vibrations of every connection but also the conformation of the structures. The results of the immobilization showed that the grafting of biomolecules on functionalised surfaces was specific and efficient. The functionalisation of gold surface by monolayer deposition constituted at the end an efficient and low cost technique allowing to anchor biomolecules and can be used for multitude applications. The last step consisting of the synthesis of photocrosslinkable monomer was started and still investigated.
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The effect of immobilization on ligamentous healing and strength of the medial collateral ligament of the rat knee

Pisesky, Wayne Anthony January 1982 (has links)
The purpose of this study was to determine the effects of varying periods of immobilization on ligamentous healing and strength in a rat experimental model. Sixty-one mature male Wistar rats were used. The left knee medial collateral ligament was surgically exposed, divided, and repaired. The rats were randomly placed into one of four groups: Group A, no immobilization, Group B, 2 weeks' immobilization, Group C, 6 weeks' immobilization, and Group D, 10 weeks' immobilization of the operated limb. The right knee served as a control. The ligaments were studied histologically and biomechanically at 2 weeks, 6 weeks, 10 weeks and 20 weeks post-operatively. Histologic samples were objectively evaluated with the light microscope using a Maturity Index Score and Scale that were devised based on the numbers and orientation of the fibroblasts and the amount and orientation of the collagen fibres. Ligament-bone preparations were studied using an Instron material testing machine to determine the biomechanical properties of the ligament until failure. Utilizing the Maturity Index Score and Scale, it was shown that Group A, with no immobilization, matured more rapidly than the other groups, and achieved full maturity at 20 weeks post-operatively. The other groups all showed a retarded rate of healing while immobilized. The electron microscopic study supported this data by demonstrating the level of metabolic activity of the fibroblasts which decreased with increasing maturity and by demonstrating that the size, amount and orientation of the collagen fibers increased with mobilization. The biomechanical testing showed that at 2 weeks post-operative, Group A had achieved a strength which was 46% of controls while Group B was only 29% of controls (p = 0.055). At 6 weeks Group A was 65% of controls, Group B was 56% of controls and Group C was 39% of controls (p = 0.0004). At 20 weeks Group A was 83% of controls, Group B was 71% of controls, Group C was 66% of controls and Group D was 48% of controls (p = 0.0005). Group A was 71% stronger than Group D at this time, indicating that the healing medial collateral ligament attained a greater strength and histologically matured more rapidly if mobilization is begun immediately. / Science, Faculty of / Botany, Department of / Zoology, Department of / Graduate

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