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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.
181

Fabrication of flexible, biofunctional architectures from silk proteins

Pal, Ramendra K 01 January 2017 (has links)
Advances in the biomedical field require functional materials and processes that can lead to devices that are biocompatible, and biodegradable while maintaining high performance and mechanical conformability. In this context, a current shift in focus is towards natural polymers as not only the structural but also functional components of such devices. This poses material-specific functionalization and fabrication related questions in the design and fabrication of such systems. Silk protein biopolymers from the silkworm show tremendous promise in this regard due to intrinsic properties: mechanical performance, optical transparency, biocompatibility, biodegradability, processability, and the ability to entrap and stabilize biomolecules. The unique ensemble of properties indicates opportunities to employ this material into numerous biomedical applications. However, specific processing, functionalization, and fabrication techniques are required to make a successful transition from the silk cocoon to silk-based devices. This research is focused on these challenges to form silk-based functional material and devices for application in areas of therapeutics, bio-optics, and bioelectronics. To make silk proteins mechanically conformable to biological tissues, the first exploration is directed towards the realization of precisely micro-patterned silk proteins in flexible formats. The optical properties of silk proteins are investigated by showing the angle-dependent iridescent behavior of micropatterned proteins, and developing soft micro-optical devices for light concentration and focusing. The optical characteristics and fabrication process reported in the work can lead to the future application of silk proteins in flexible optics and electronics. The microfabrication process of silk proteins is further extended to form shape-defined silk protein microparticles. Here, the specificity of shape and the ability to form monodisperse shapes can be used as shape encoded efficient cargo and contrast agents. Also, these particles can efficiently entrap and stabilize biomolecules for drug delivery and bioimaging applications. Next, a smart confluence of silk sericin and a synthetic functional polymer PEDOT:PSS is shown. The composite materials obtained have synergistic effects from both polymers. Silk proteins impart biodegradability and patternability, while the intrinsically conductive PEDOT:PSS imparts electrical conductivity and electrochemical activity. Conductive micro architectures on rigid as well as flexible formats are shown via a green, water-based fabrication process. The applications of the composite are successfully demonstrated by realizing biosensing and energy storage devices on rigid or flexible forms. The versatility of the approach will lead to the development of a variety of applications such as in bio-optics, bioelectronics, and in the fundamental study of cellular bio electrogenic environments. Finally, to expand the applicability of reported functional polymers and composites beyond the microscale, a method for silk nano-patterning via electron beam lithography is explored. The technique enables one-step fabrication of user defined structures at the submicron and nano-scales. By virtue of acrylate chemistry, a very low energetic beam and dosage are required to form silk nano-architectures. Also, the process can form both positive and negative features depending on the dosage. The fabrication platform can also form nano scale patterns of the conductive composite. The conductive measurements confirm the formation of conductive nanowires and the ability of silk sericin to entrap PEDOT:PSS particles in nanoscale features.
182

Silk Weaving in Sweden During the 19th Century : Textiles and texts - An evaluation of the source material

Ciszuk, Martin January 2012 (has links)
Silk-weaving in Sweden during the 19th century. Textiles and texts - An evaluation of the source material. With the rich material available, 19th century silk-weaving invites to studies on industrialisation processes. The purpose of this licentiate thesis is to present and discuss an empirical material regarding silk production in Sweden in the 19th century, to examine the possibilities and problems of different kinds of materials when used as source materials, and to describe how this material can be systematized and analysed in relation to the perspective of a textile scientific interpretation. The introductory sections of the thesis provide a background to textile research and the subject of textile science. This is followed by an overview of previous research on silk-weaving in Sweden and a historical overview of silk-weaving in Sweden, the Jacquard machine, and the K.A. Almgren Sidenväveri, where large parts of the source material have been preserved. After these overviews, the research material is described and systematized: first the main materials, textiles, machines and other objects, and then the various written sources. By way of conclusion, the empirical material is summarized in a critical discussion where the various groups of materials are evaluated in comparison to one another. A discussion on theory and methodology regarding objects as sources and the use of experience-based knowledge in academic research is developed in connection to the critical discussion. Finally, the potential of the material is demonstrated through a textile example. The presentation is an introduction to the cultural-historical analysis that will follow in the PhD thesis. Here, the empirical material will be analysed through the use of knowledge in handicrafts, which may create new dimensions of silk production in Sweden and the complexity of the industrialisation process.
183

Characterization and Biomedical Applications of Recombinant Silk-Elastinlike Protein Polymers

Teng, Weibing January 2012 (has links)
Biomaterials requirements nowadays are becoming more and more specialized to meet increasingly demanding needs for biomedical applications such as matrices for tissue scaffolds. Among various useful classes of biomaterials, protein-based materials have been extensively pursued as they can offer a wide range of material properties to accommodate a broader spectrum of functional and performance requirements. The advent of genetic engineering and recombinant DNA technology has enabled the production of new protein-based biopolymers with precisely controlled amino acid sequence. As an example, silk-elastinlike protein (SELP) polymers consisting of polypeptide sequences from native silk of remarkable mechanical strength and polypeptide sequences from native elastin that is extremely durable and resilient have been produced. In this dissertation, a particular silk-elastinlike protein copolymer, SELP-47K, was cast into film form, and fully characterized for its material properties, including the mechanical property, secondary structure transition, optical transparency, surface, and other physical, chemical properties. The relationship between mechanical property and protein secondary structure was investigated as well. In addition, the material property tunability which can be induced by physical, mechanical, and chemical treatments has been explored. It is worth noting that the physically crosslinked SELP-47K films displayed mechanical properties comparable to those of native elastin obtained from bovine ligament. Secondary structure study through Raman and FTIR spectra showed that methanol treatment is capable of inducing theβ-sheet crystallization of silklike blocks, which act as physical crosslinks in the protein polymer chain network, thus stabilizing the protein structure and conferring the improved material integrity. The SELP-47K protein polymer thin films displayed excellent optical transparency. In particular, its excellent optical transmittance (over 90%) in visible light range may indicate SELPs can be a family of promising biomaterial candidate for ocular applications. Besides material property characterization, SELP-47K protein polymer has been fabricated into a variety of drug delivery devices to sustainably release a common ocular antibiotic, ciprofloxacin over a period of up to 220 h, with near-first order kinetics.
184

Production of Synthetic Spider Silk

Hekman, Ryan Matthew 01 January 2018 (has links)
Spider silk is a material that both has impressive mechanical properties and is also environmentally friendly. Though there are limitless potential engineering applications for such materials, industrial production of spider silk has proven to be challenging. Farming silk from spiders, as is done with silkworms, is not a viable option for large-scale production of spider silk due to the venomous and predatory nature of spiders. Here, an attempt is made to express synthetic spider silk minifibroins heterologously in Escherichia coli, to purify the recombinant spidroins from cell lysate, and to spin them into artificial fibers through a biomimetic process. Silk minifibroins were designed to be similar to Major Ampullate Spidroin 1 from Latrodectus hesperus. Synthetic fibers were examined by scanning electron and light microscopy, and their mechanical properties were tested by a tensometer. Properties of synthetic silk were compared to those of native dragline silk from the same species from which their design was inspired, revealing synthetic silk fibers with lower breaking stress and breaking strain.
185

Dinâmica da inovação da sericicultura no Brasil / Dynamics of sericulture innovation in Brazil

Giacomin, Alessandra Maria 23 August 2018 (has links)
O Brasil destaca-se como maior produtor de seda em escala comercial no Ocidente e o quinto maior no mundo, devido ao eficiente sistema integrado de produção, que qualifica os fios de seda brasileiros como de alta qualidade. A sericicultura é a criação do Bombyx mori L. (bicho-da-seda) para obtenção dos casulos de seda para a fiação. A atividade emprega, no Brasil, aproximadamente, 2.500 famílias no meio rural, gerando renda por cerca de 8 a 9 meses do ano, contribuindo para a fixação delas ao campo. Além disso, cerca de 2.000 funcionários trabalham nas empresas de fiação no meio urbano, e o total de empregos, contando com os empregos indiretos, associados à atividade, somam, aproximadamente, 20.000. Esta pesquisa teve como objetivo apresentar a dinâmica da inovação da sericicultura no Brasil e as medidas que vêm sendo tomadas nesse sentido. Os dados, para elaboração deste estudo, foram coletados por meio de análise bibliográfica, assim como, visitas técnicas às empresas e aos produtores ligados à sericicultura nos estados do Paraná e São Paulo. Foram realizadas entrevistas com quatro sericicultores, juntamente com representantes das empresas Fiação de Seda BRATAC S.A., Fiação de Seda Artesanal O Casulo Feliz, Instituto Vale da Seda e com Enéas Neto, estilista residente da marca Vale da Seda. As principais modernizações constatadas visam diminuir o esforço físico do trabalhador rural e aumentar a produtividade, mantendo os padrões de qualidade. Constatou-se, nas visitas e entrevistas aos produtores rurais, que a sericicultura é, na maioria dos casos, a principal fonte de renda familiar, afirmando a importância social e econômica da referida atividade e que, mesmo após anos anteriores de declínio, vem se mostrando promissora no Brasil, com aumentos gradativos nas últimas safras, tornando-se uma atividade bastante rentável. Por meio das entrevistas com os empresários e representantes do setor, relacionados com a produção de seda no Brasil, percebe-se que se sentem otimistas com relação ao futuro da seda, pois existe hoje uma maior preocupação com o uso de produtos provenientes de extração mais sustentável, duráveis e com maior valor agregado e, a seda, se enquadra nesses requisitos. Além disso, estudos preliminares indicam uma correlação positiva entre a produção de seda e a mitigação da Pegada de Carbono. Desse modo, a sericicultura, de forma sustentável, ética e socialmente responsável, poderá apresentar cada vez maior destaque e, por consequência, refletir positivamente na economia brasileira como um todo. Conclui-se que a sericicultura é uma atividade economicamente viável para o Brasil, o qual apresenta condições de solo e clima favoráveis para a criação do bicho-da-seda, em diversas regiões de seu território, com a possibilidade de gerar empregos e renda, tanto na área rural, quanto na urbana. Impulsionada pela mecanização e modernização da atividade agropecuária, a sericicultura nacional vem retomando lugar de destaque / Brazil stands out as the largest commercial scale silk producer in the West and the fifth largest in the world due to its efficient integrated production system, which qualifies Brazilian silk yarns as high quality. The sericulture is the creation of Bombyx mori L. (silkworm) to obtain silk cocoons for spinning. The activity employs approximately 2,500 rural families in Brazil, generating income for about 8 to 9 months of the year, contributing to their setting in the field. In addition, around 2,000 employees work in the spinning companies and the total amount of jobs, added to the indirect jobs by the activity, is, approximately, 20,000. This research aimed to present the dynamic of sericulture innovation in Brazil and the measures that have been taken in this direction. All the data for the preparation of this study were collected through bibliographic analysis, as well as technical visits to companies and producers linked to sericulture in the states of Parana and Sao Paulo. Interviews were conducted with four sericulturists, along with representatives of the spinning companies of Silk BRATAC S.A., spinning of handmade silk O Casulo Feliz, Silk Valley Institute and with Eneas Neto, resident designer of the Silk Valley brand. The main modernizations observed aim to reduce the physical effort of the rural worker and increase productivity, maintaining the renowned Brazilian quality standards. In the visits and interviews with rural producers, sericulture is, in most cases, the main source of income of the family, affirming the social and economic importance of this activity, and that, even after previous years of decline, showing promising in Brazil, with gradual increases in the last harvests, becoming a very profitable activity for producers of other crops. Through interviews with businessmen and industry representatives related to the production of silk in Brazil, it is perceived that they feel optimistic about the future of silk, as there is a greater concern with the use of products from more sustainable extraction, durable and with higher added value, and silk meets these requirements. Furthermore, preliminary studies indicate a positive correlation between silk production and Carbon Footprint mitigation. In this way, sericulture, in a sustainable, ethical and socially responsible manner, may be increasingly prominent, and consequently, positively reflecting on the Brazilian economy as a whole. It is concluded that sericulture is an economically viable activity for Brazil that presents favorable soil and climate conditions for the creation of silkworms, as well as generates jobs and income in the rural area, contributing to a decrease in the rural exodus. Driven by the mechanization and modernization of agricultural activity, the national sericulture has resumed a prominent place
186

Recombinant spider silk with antimicrobial properties

Nilebäck, Linnea January 2013 (has links)
Immobilizing antimicrobial substances onto biocompatible materials is an important approach for the design of novel, functionalized medical devices. By choosing antimicrobial substances from innate immune systems, the risk for development of resistance in pathogenic microbes is lower than if conventional antibiotics are used. Combining natural antimicrobial peptides and bactericidal enzymes with strong and elastic spider silk through recombinant protein technology would enable large-scale production of materials that could serve as functionalized wound dressings. Herein, fusion proteins with the engineered spider silk sequence 4RepCT and five different antimicrobial substances were constructed using two different strategies. In the first, the fusion proteins had a His-tag as well as a solubility-enhancing domain N-terminally to the antimicrobial agent during expression. The tags were cleaved and separated from the target protein during the purification process. The other approach provided a His-tag but no additional solubility domain. The antimicrobial agents included in the work were a charge engineered enzyme and four antimicrobial peptides herein called Peptide A, Peptide B, Peptide C and Peptide D. Four out of five fusion proteins could be expressed in Escherichia coli without exhibiting noticeable toxicity to the host. However, most target proteins were found in the non-soluble fraction. For D-4RepCT, neither soluble nor non-soluble proteins were identified. An operating strategy for expression and purification of antimicrobial spider silk proteins was developed, where the construct system providing the solubility-enhancing domain N-terminally to the antimicrobial sequence, and long time expression at low temperatures is a promising approach. The fusion proteins A-4RepCT and C-4RepCT could be produced in adequate amounts, and they proved to possess the ability to assemble into stable fibers. When incubating solutions of Escherichia coli on the functionalized silk material A-4RepCT, it showed to decrease the number of living bacteria in solution, in contrary to wild-type 4RepCT on which bacteria continued to proliferate. Initial studies of the viability of bacteria adhered to the surface of the functionalized spider silk are so far inconclusive. A larger sample size, complementary experiments and methodology optimization is needed for a proper assessment of antibacterial properties. However, preliminary results for the development of antimicrobial spider silk are positive, and the approach elaborated in this work is believed to be applicable for the construction of functional spider silk with a wide range of natural antimicrobial agents for future wound healing applications.
187

Spider dragline silk : molecular properties and recombinant expression /

Rising, Anna, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
188

Les Routes de la lutte / The Wrestling roads

Philippe, Tanguy 25 June 2012 (has links)
La lutte est une mise en jeu de la force entre deux antagonistes qui tentent de se maîtriser dans un corps-à corps. Cette activité physique au principe simple est présente dans une majorité de cultures sous des formes élaborées. Elle constitue un motif imaginaire, représentant les oppositions fondamentales des mythes ou est organisée sous forme rituelle, pour que son résultat augure de la prospérité collective. Les « styles » de lutte, formes durables et localisées, correspondent à définition de la force dans les cultures et les civilisations, prenant en compte un idéal imaginaire et une construction fine desavoirs pratiques dans un système règlementaire cohérent et stimulant.En complément d’une présence universelle et de pratiques locales et originales, il est possible de rapprocher certains styles disposant de caractéristiques similaires, ce qui montre une diffusion de la lutte sur la longue durée. Les formes élaborées ont une distribution géographique régulière, correspondant aux routes de circulation de culture. Sur les routes de la soie, les styles se sont diffusés tout en se distinguant progressivement. Le long de la « Route celtique », ils ont connu une histoire complexe d’identification et de réunion, influençant même la synthèse de styles internationaux.La lutte, sur la base d’une formule d’opposition simple et modifiable, a été finement élaborée, développée en desstructures sociales plus complexes, et véhiculée le long des routes de culture. Ce cheminement sur la longue durée illustre la constitution du sport comme objet de culture, et montre comment l’ancrage du jeu et sa diffusion contribuent à créer et à enrichir la construction du sport / Wrestling is a play of strength between two antagonists who aim to master each other in a hand-to-hand opposition. The principle of this activity is fairly simple and well known in a majority of cultures and civilizations. It can be found in different elaborated forms. Wrestling symbolizes an imaginary representation of the fundamental opposition in mythology or acts as a ritual challenge in which the outcome foreshadows the collective wealth. Each wrestling style corresponds to one culture’s definition of the Strength concept, which takes into account an ideal imaginary, and a subtle construction of practical knowledge in a consistent and stimulating rules system.In addition to a universal presence and local original practices, we can easily notice similarities between styles and a wide set of common characteristics. It illustrates and implies a long-term diffusion. Elaborated forms have a steady geographical distribution, which corresponds to the roads of cultural circulation. Along the Silk Road styles spread out while they gradually evolved and grew apart. On the “Celtic Road” they experienced a complex History of identification and meeting that influenced the synthesis of international styles.Wrestling is an elementary and flexible system that has been deeply developed in more complex forms and spread out along the culture roads. This long-term progression illustrates the cultural character of sport and shows how its rooting and diffusion contribute into enriching the sport construction
189

Dinâmica da inovação da sericicultura no Brasil / Dynamics of sericulture innovation in Brazil

Alessandra Maria Giacomin 23 August 2018 (has links)
O Brasil destaca-se como maior produtor de seda em escala comercial no Ocidente e o quinto maior no mundo, devido ao eficiente sistema integrado de produção, que qualifica os fios de seda brasileiros como de alta qualidade. A sericicultura é a criação do Bombyx mori L. (bicho-da-seda) para obtenção dos casulos de seda para a fiação. A atividade emprega, no Brasil, aproximadamente, 2.500 famílias no meio rural, gerando renda por cerca de 8 a 9 meses do ano, contribuindo para a fixação delas ao campo. Além disso, cerca de 2.000 funcionários trabalham nas empresas de fiação no meio urbano, e o total de empregos, contando com os empregos indiretos, associados à atividade, somam, aproximadamente, 20.000. Esta pesquisa teve como objetivo apresentar a dinâmica da inovação da sericicultura no Brasil e as medidas que vêm sendo tomadas nesse sentido. Os dados, para elaboração deste estudo, foram coletados por meio de análise bibliográfica, assim como, visitas técnicas às empresas e aos produtores ligados à sericicultura nos estados do Paraná e São Paulo. Foram realizadas entrevistas com quatro sericicultores, juntamente com representantes das empresas Fiação de Seda BRATAC S.A., Fiação de Seda Artesanal O Casulo Feliz, Instituto Vale da Seda e com Enéas Neto, estilista residente da marca Vale da Seda. As principais modernizações constatadas visam diminuir o esforço físico do trabalhador rural e aumentar a produtividade, mantendo os padrões de qualidade. Constatou-se, nas visitas e entrevistas aos produtores rurais, que a sericicultura é, na maioria dos casos, a principal fonte de renda familiar, afirmando a importância social e econômica da referida atividade e que, mesmo após anos anteriores de declínio, vem se mostrando promissora no Brasil, com aumentos gradativos nas últimas safras, tornando-se uma atividade bastante rentável. Por meio das entrevistas com os empresários e representantes do setor, relacionados com a produção de seda no Brasil, percebe-se que se sentem otimistas com relação ao futuro da seda, pois existe hoje uma maior preocupação com o uso de produtos provenientes de extração mais sustentável, duráveis e com maior valor agregado e, a seda, se enquadra nesses requisitos. Além disso, estudos preliminares indicam uma correlação positiva entre a produção de seda e a mitigação da Pegada de Carbono. Desse modo, a sericicultura, de forma sustentável, ética e socialmente responsável, poderá apresentar cada vez maior destaque e, por consequência, refletir positivamente na economia brasileira como um todo. Conclui-se que a sericicultura é uma atividade economicamente viável para o Brasil, o qual apresenta condições de solo e clima favoráveis para a criação do bicho-da-seda, em diversas regiões de seu território, com a possibilidade de gerar empregos e renda, tanto na área rural, quanto na urbana. Impulsionada pela mecanização e modernização da atividade agropecuária, a sericicultura nacional vem retomando lugar de destaque / Brazil stands out as the largest commercial scale silk producer in the West and the fifth largest in the world due to its efficient integrated production system, which qualifies Brazilian silk yarns as high quality. The sericulture is the creation of Bombyx mori L. (silkworm) to obtain silk cocoons for spinning. The activity employs approximately 2,500 rural families in Brazil, generating income for about 8 to 9 months of the year, contributing to their setting in the field. In addition, around 2,000 employees work in the spinning companies and the total amount of jobs, added to the indirect jobs by the activity, is, approximately, 20,000. This research aimed to present the dynamic of sericulture innovation in Brazil and the measures that have been taken in this direction. All the data for the preparation of this study were collected through bibliographic analysis, as well as technical visits to companies and producers linked to sericulture in the states of Parana and Sao Paulo. Interviews were conducted with four sericulturists, along with representatives of the spinning companies of Silk BRATAC S.A., spinning of handmade silk O Casulo Feliz, Silk Valley Institute and with Eneas Neto, resident designer of the Silk Valley brand. The main modernizations observed aim to reduce the physical effort of the rural worker and increase productivity, maintaining the renowned Brazilian quality standards. In the visits and interviews with rural producers, sericulture is, in most cases, the main source of income of the family, affirming the social and economic importance of this activity, and that, even after previous years of decline, showing promising in Brazil, with gradual increases in the last harvests, becoming a very profitable activity for producers of other crops. Through interviews with businessmen and industry representatives related to the production of silk in Brazil, it is perceived that they feel optimistic about the future of silk, as there is a greater concern with the use of products from more sustainable extraction, durable and with higher added value, and silk meets these requirements. Furthermore, preliminary studies indicate a positive correlation between silk production and Carbon Footprint mitigation. In this way, sericulture, in a sustainable, ethical and socially responsible manner, may be increasingly prominent, and consequently, positively reflecting on the Brazilian economy as a whole. It is concluded that sericulture is an economically viable activity for Brazil that presents favorable soil and climate conditions for the creation of silkworms, as well as generates jobs and income in the rural area, contributing to a decrease in the rural exodus. Driven by the mechanization and modernization of agricultural activity, the national sericulture has resumed a prominent place
190

Ação da proteína sericina em lesão nervosa isquiática, associada ao exercício físico de natação, em ratos wistar / Action of sericin protein in ischiatic nervous injury, associated with physical exercise of swimming, in wistar rats

Debastiani, Jean Carlos 11 August 2017 (has links)
Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-02-23T17:32:36Z No. of bitstreams: 2 Jean_Debastiani2017.pdf: 2133266 bytes, checksum: 2c24ca5fdccdfabea585b210fcf8110f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-23T17:32:36Z (GMT). No. of bitstreams: 2 Jean_Debastiani2017.pdf: 2133266 bytes, checksum: 2c24ca5fdccdfabea585b210fcf8110f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-11 / Lesions in the peripheral nervous system imply active in voluntary motor function, leading to increased morbidity, incapacities in work activities and daily life, with consequent increase in costs for the public health system. Effective treatments research, studies have shown that physical and efficient exercise in functional recovery after the development of the nervous system, which is not a process of nerve regeneration. In addition, several products are being investigated with no intention to aid recovery, there are no cases of sericin silk protein, studies indicate its action in the healing process, contributing in the tissue regeneration in chronic lesions. The aim of this study was to verify the role of sericin associated with a swimming exercise protocol, with overload, without repair of the sciatic nerve of Wistar rats after nerve compression. For this purpose, 80 animals were divided into five groups of 16 animals each, being: control (CON), Injury (LES), injury-sericin (LSER), injury-swimming (LNAT) and injury-sericin-swimming (LSRNT). The animals of the LES, LSER, LNAT and LSRNT groups were submitted to compression of the sciatic nerve, however LSER and LSRNT received an application of hydrolyzed sericin protein directly on a nerve lesion at the time of surgery. The LNAT and LSRNT groups underwent swimming exercise with a load of 10% of the body weight of the animal, for cycles of five days of training and two of rest, of 1 or 3 cycles, according to the euthanasia times, and with progression of time, being in the first cycle 15 minutes of exercise, in the second 20 minutes and 25 minutes in the third cycle. During the experimental period, animals as well as nociception, by the digital "Von Frey" filament test and function analysis by means of the functional index of the ischiatic. Euthanasia was performed in two stages, the sample being euthanized on the 8th postoperative day, and the remainder on the 22nd day. Two fragments of the nerve, distal to the nerve injury, were collected and prepared for light microscopy analysis, stained with hematoxylin-eosin and pre-stained with carbon tetraoxide, being observed as morphological and morphometric characteristics of the nerve fiber. The results were analyzed statistically as their normality and one-way ANOVA was performed, with LSD post-test. Regarding the euthanized animals on the eighth day, a sericin applied directly on the sciatic nerve lesion, presented proinflammatory characteristics, and an isolated swimming showed an improvement of hypernociception in relation to the other interventions. There were no signs of acceleration of the nerve repair process on the eighth day after injury. In relation to the euthanized animals on the 22nd day, an association of sericin and swimming treatment evidenced a regulating effect of the serinin pro-inflammatory action by the resisted swimming exercise, and an isolated sericin caused exacerbation of the inflammatory process and resistance swimming exercise, It showed good evolution to the nociceptive threshold and allodynia. / Lesões no sistema nervoso periférico implicam em alterações na função motora voluntária, levando ao aumento da morbidade, incapacidades nas atividades laborais e de vida diária, com consequente aumento dos custos para o sistema de saúde público. Na busca de tratamentos efetivos, estudos têm demonstrado que o exercício físico é eficiente na recuperação funcional após lesão do nervo isquiático, sendo que a natação pode produzir a aceleração no processo de regeneração nervosa. Além disso, diversos produtos vêm sendo investigados no intuito de auxiliar a recuperação, no caso da proteína da seda sericina, estudos apontam sua ação no processo de cicatrização, contribuindo na regeneração tecidual em lesões crônicas. Observados estes aspectos, esta pesquisa teve por objetivo verificar o papel da sericina associada a um protocolo de exercício de natação, com sobrecarga, no reparo do nervo isquiático de ratos Wistar após compressão nervosa. Para tanto, foram utilizados 80 animais divididos em cinco grupos de 16 animais cada, sendo: controle (CON), lesão (LES), lesão-sericina (LSER), lesão-natação (LNAT) e lesão-sericina-natação (LSRNT). Os animais dos grupos LES, LSER, LNAT e LSRNT foram submetidos à compressão do nervo isquiático, porém somente LSER e LSRNT receberam a aplicação de proteína sericina hidrolisada diretamente sobre a lesão nervosa no momento da cirurgia. Os grupos LNAT e LSRNT realizaram exercício de natação com carga de 10% do peso corporal do animal, por ciclos de cinco dias de treino e dois de descanso, de 1 ou 3 ciclos, de acordo com os tempos de eutanásia, e com progressão de tempo, sendo no primeiro ciclo 15 minutos de exercício, no segundo 20 minutos e 25 minutos no terceiro ciclo. Durante o período experimental, os animais foram avaliados quanto à nocicepção, pelo teste de filamento tipo “Von Frey” digital e análise de função por meio do índice funcional do isquiático. A eutanásia foi realizada em duas etapas, sendo metade da amostra eutanasiada no 8º dia de pós-operatório, e o restante no 22º dia. Dois fragmentos do nervo, distais à lesão nervosa, foram coletados e preparados para analise em microscopia de luz, corado com hematoxilina-eosina e pré-corado com tetróxido de ósmio respectivamente, sendo observadas as características morfológicas e morfometricas da fibra nervosa. Os resultados obtidos foram analisados estatisticamente quanto sua normalidade e realizado ANOVA unidirecional, com pós-teste de LSD. Em relação aos animais eutanasiados no oitavo dia, a sericina aplicada diretamente sobre a lesão nervosa isquiática, apresentou características pró-inflamatórias, já a natação isolada mostrou melhora da hipernocicepção em relação às demais intervenções. Não houve sinais de aceleração do processo de reparo nervoso no oitavo dia após a lesão. Já em relação aos animais eutanasiados no 22º dia, a associação do tratamento de sericina e natação evidenciou um efeito regulador da ação pró-inflamatória da sericina pelo exercício resistido de natação, já a sericina isolada provocou exacerbação do processo inflamatório e o exercício de natação resistido, mostrou boa evolução quanto ao limiar nociceptivo e alodinia.

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