The use of enzymes as catalysts in organic synthesis constitutes an attractive alternative to conventional chemical catalysis. Enzymes are non-toxic and biodegradable and they can operate under mild reaction conditions. Furthermore, they often display high chemo-, regio- and stereoselectivity, enabling specific reactions with single product outcome. By the use of protein engineering, enzymes can be altered for the specific needs of the researcher. The major part of this thesis describes engineering of lipase A from Candida antarctica (CalA), for improved enantioselectivity in organic synthetic transformations. The first part of the thesis describes a highly combinatorial method for the introduction of mutation sites in an enzyme library. By the simultaneous introduction of nine mutations, we found an enzyme variant with five out of the nine possible mutations. This quintuple variant had an enlarged active site pocket and was enantioselective and active for our model substrate, an ibuprofen ester. This is a bulky substrate for which the wild-type enzyme shows no enantioselectivity and very poor activity. In the second part of the thesis, we continued our approach of combinatorial, focused enzyme libraries. This time we aimed at decreasing the alcohol pocket of CalA, in order to increase the enantioselectivity for small and medium-sized secondary alcohols. The enzyme library was bound on microtiter plates and screened by a transacylation reaction in organic solvent. This library yielded an enzyme variant with high enantioselectivity for the model substrate 1-phenyl ethanol, and high to excellent selectivity for other alcohols tested. Screening in organic solvent is advantageous since a potential hit is more synthetically useful. In the third part of the thesis, we used manipulated beads of controlled porosity glass (EziG™) for enzyme immobilization, and demonstrated the generality of this carrier for several enzyme classes. EziG™ allowed fast enzyme immobilization with simultaneous purification and yielded active biocatalysts in all cases. The last project describes the function of the proposed active site flap in CalA. In our study, we removed this motif. The engineered variant was compared to the wild-type enzyme by testing the amount of interfacial activation and the selectivity for certain alcohols. We showed that the motif is indeed controlling the entrance to the active site and that the flap is not part of the enantioselectivity determining machinery. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

Abstract To investigate the turnover of type IV collagen in skeletal muscle in conditions where muscle function is impaired, type IV collagen and proteins regulating its degradation were studied during 1, 3 and 7 days of immobilization, 3- and 10-day glucocorticoid treatment and in neuromuscular diseases. In addition, fibrillar type I and III collagens were studied during immobilization and in neuromuscular diseases. The mRNA levels of type I, III and IV collagens were decreased during immobilization and during 10-day dexamethasone treatment. Gene expression and quantity of (pro)MMP-2 was increased during immobilization but decreased during dexamethasone treatment. The expression of TIMP-2 was decreased both during immobilization and dexamethasone treatment. Decreased gene expression and increased degradation caused decreased concentration of type IV collagen, suggesting net degradation of type IV collagen during immobilization. While the gene expression and degradation were decreased during dexamethasone treatment, the amount of type IV collagen was not changed. Dexamethasone thus seemed to slow down the turnover of type IV collagen. Decreased mRNA levels of collagens and prolyl 4-hydroxylase suggest decreased biosynthesis of collagens during immobilization. The mRNA levels of collagens I, III and IV were increased in polyneuropathy and polymyositis. The concentration and staining intensity of type IV collagen was increased in polyneuropathy, as was also the quantity and staining intensity of (pro)MMP-9. The results suggest accumulation of type IV collagen in the basement membranes of muscle cells and capillaries in polyneuropathy muscles. Lengthened position during immobilization partly prevented the atrophy and changes in collagen metabolism in plantarflexors. Endurance running was effective in preventing muscle atrophy during dexamethasone treatment, but exercise did however fail to prevent the changes observed in type IV collagen synthesis and degradation.

Background: The patient's prerequisites form the basis for the pre-and postoperative care period. One of the aspects that affect health care is the patient's physical activity where immobilizing surgery involves atrophy of muscle mass. A low preoperative activity level, perioperative immobilization and postoperative immobilization increase the risk of postoperative complications. Aim: The purpose was to investigate how much skeletal muscle mass patients lose related to immobilizing surgery and how immobilization affects the patient's care time postoperatively. Method: A literature study that reviewed 12 original articles. The articles were reviewed according to Forsberg and Wengström (2016) where article’s contents and results were compared with the aim of this literature study. Results: After examination, no general loss of muscle mass after immobilized surgery could be identified. The muscle mass's ability to atrophy varies depending on the area of surgery and individual-based conditions. However, muscle mass and its quality were identified as a potential prognostic marker for how post-operative care time will play out where lower levels of muscular quality imply increased risk of complications and mortality. Care time for patients with a low muscle grade has been identified as prolonged related to immobilizing surgery. A care period that can be shortened by muscular activation in the form such as electrical stimulus or resistance exercises. Conclusion: The conclusion of this literature study is that the muscle mass lost in immobilized surgery and how postoperative care is affected is individual-based and influenced by preoperative muscle size and type of surgical procedure. Further research is needed on preoperative and postoperative skeletal muscle mass measurement and a routine for measuring muscle mass, since muscle atrophy has been identified as an important marker for postoperative care and survival. / Bakgrund: Patientens förutsättningar ligger till grund för hur den pre- och postoperativa vårdtiden kommer att fortlöpa. En av aspekterna som påverkar vården är patientens fysiska aktivitet där immobiliserande kirurgi innebär atrofi av muskelmassa. En låg preoperativ aktivitetsnivå, perioperativ immobilisering och postoperativ immobilisering ökar risken för postoperativa komplikationer relaterade till muskelatrofi. Syfte: Syftet var att undersöka hur mycket skelettmuskulatur patienter förlorar i samband med immobiliserande operation samt hur immobiliseringen påverkar patientens vårdtid postoperativt. Metod: En litteraturstudie som granskade 12 originalartiklar. Artiklarna granskades enligt Forsberg och Wengström (2016) där innehåll och resultat jämfördes med denna litteraturstudies syfte. Resultat: Efter granskning har ingen generell förlust av muskelmassa efter kirurgi kunnat identifieras. Muskelmassans förmåga att atrofiera varierar beroende på operationsområde och individbaserade förutsättningar. Muskelmassan och dess kvalitet kunde dock identifieras som en prognostisk markör för hur den postoperativa vårdtiden kommer att fortlöpa där lägre grad av muskulär kvalitet innebär ökad risk för komplikationer och mortalitet. Vårdtiden för patienter med muskelgrad av låg kvalitet har kunnat identifieras som förlängd i samband med immobiliserande kirurgi. En vårdtid som kan förkortas genom muskulär aktivering i form av t.ex. elektrisk stimulans eller motståndsövningar. Slutsats: Konklusionen av denna litteraturstudie är att den muskelmassa som förloras vid immobiliserande kirurgi samt hur den postoperativa vårdtiden påverkas är individbaserat och påverkas av preoperativ muskelgrad och typ av kirurgiskt ingrepp. Efter genomförd granskning eftersöks vidare forskning gällande preoperativ och postoperativ mätning av skelettmuskelmassa och en standardiserad rutin för att mäta muskelmassa, detta då muskelatrofi har identifierats som en viktig markör för postoperativ vård och överlevnad.

Ehemalige Urangruben tragen durch das anfallende Flutungswasser maßgeblich zur Ausbreitung von Schadstoffen wie Uran und Arsen in teils dicht besiedelte Gebiete bei. Um die Prozesse in den unterirdischen Gruben besser zu verstehen und alternative Strategien zur konventionellen, kostenintensiven Wasserbehandlung entwickeln zu können, war das Ziel der Arbeit, mikrobielle Gemeinschaften aus drei gefluteten Uranerzbergwerken in Sachsen, namens Pöhla, Schlema und Zobes, die unterschiedliche Flutungsstadien repräsentierten, zu charakterisieren und den mikrobiellen Einfluss auf die Mobilität von Uran und Arsen zu untersuchen. Um herauszufinden, welche Mikroorganismen die hydrochemischen Vorgänge im Untergrund der Uranerzbergwerke beeinflussen könnten, wurde die Diversität und Zusammensetzung mikrobieller Gemeinschaften mittels Pyrosequenzierung eines Fragments des 16S rRNA Gens (16S rDNA) und CARD-FISH ermittelt. Wenngleich Clusteranalysen zeigten, dass sich die planktonischen Gemeinschaften hinsichtlich ihrer bakteriellen Zusammensetzung zwischen den drei Uranerzbergwerken unterschieden, wurden alle von chemolithotrophen Schwefeloxidierern der Beta- und Epsilonproteobacteria dominiert, die mit den Gattungen Thiobacillus und Sulfuritalea bzw. Sulfuricurvum und Sulfurimonas vertreten waren. Im Unterschied zu den planktonischen Gemeinschaften bestanden in situ Biofilme, die auf BACTRAPs während einer 3-monatigen Exposition im Flutungswasser anwuchsen, laut Pyrosequenzierung zu einem wesentlichen, mitunter dominanten Anteil aus metall- bzw. sulfatreduzierenden Deltaproteobacteria. In Biofilmgemeinschaften aus Zobes wurden hauptsächlich Geobacter sp. detektiert, die als Fe(III)- und U(VI)-Reduzierer bekannt sind. Obwohl Archaea basierend auf den Ergebnissen der CARD-FISH-Analyse nur einen sehr geringen Anteil der planktonischen Gemeinschaften ausmachten, wurden mittels Pyrosequenzierung planktonische Euryarchaeota der Thermoprotei in allen Gruben detektiert. In planktonischen Gemeinschaften und 3-monatigen Biofilmen aus Pöhla und Zobes wurden zudem methanogene Crenarchaeota, vor allem Methanobacteria und teilweise Methanomicrobia, ermittelt. Die 16S rRNA-Analyse, die ergänzend zum DNA-basierten Ansatz durchgeführt wurde, lieferte Hinweise darauf, dass die detektierten, dominanten Mikroorganismen, Bacteria sowie Archaea, in der planktonischen Gemeinschaft aus Schlema und den Biofilmgemeinschaften stoffwechselaktiv waren. In der planktonischen Gemeinschaft aus Zobes wurden im Vergleich zur DNA-basierten Analyse höhere Abundanzen für Verrucomicrobia, Acidobacteria und Alphaproteobacteria ermittelt, deren Bedeutung offen bleibt. Untersuchungen zum mikrobiellen Stoffwechselpotential planktonischer Gemeinschaften mittels CFU- und MPN-Analysen ergaben, dass Mikroorganismen aus allen Urangruben ein breites Spektrum anaerober Reaktionen (Nitrat-, Eisen-, Mangan-, Arsenat- und Sulfatreduktion und Acetogenese) unter Laborbedingungen abdeckten. In guter Übereinstimmung mit den Sequenzierungsergebnissen konnten methanogene Mikroorganismen nur im Flutungswasser aus Pöhla und Zobes detektiert werden. Die Metaproteomanalyse ergab, dass 61,6% der Peptide in der planktonischen Gemeinschaft aus Schlema von den dominanten Epsilonproteobacteria stammten. Dagegen wurden für Zobes detektierte Peptide mehrheitlich methylotrophen und eisenoxidierenden Betaproteobacteria der Familien Methylophilaceae bzw. Gallionellaceae sowie methylotrophen Gammaproteobacteria der Methylococcaceae zugewiesen. Obwohl die Mehrheit der Proteine an der Translation beteiligt war, konnten insgesamt 49 Proteingruppen ermittelt werden, deren Vertreter für den mikrobiellen Energiestoffwechsel relevant waren. Insbesondere planktonische Gammaproteobacteria aus Zobes konnten so mit dem Kohlenstoff- und Schwefelkreislauf in Zusammenhang gebracht werden. Mithilfe von Labormikrokosmen wurde der potentielle Einfluss mikrobieller Gemeinschaften aus Schlema auf die Mobilität von Arsen und Uran im Flutungswasser mit Acetat als Elektronendonor unter anaeroben Bedingungen über einen Zeitraum von 98 Tagen untersucht. Im Vergleich zu den Kontrollen konnten sowohl die stimulierte, planktonische Gemeinschaft als auch Biofilme natürliches Arsen aus der wässrigen Phase fast vollständig entfernen. Allerdings wies der spätere Anstieg des gelösten Arsens daraufhin, dass der immobilisierte Zustand langfristig nicht stabil blieb. In stimulierten Biofilm-Ansätzen wurde Uran mit bis zu 39 ± 9% (in Anwesenheit von 7 µM natürlichem Uran) bzw. 34 ± 8% (bei Zugabe von 50 µM U(VI)) aus der wässrigen Phase langfristig (98 Tage) immobilisiert. Laserfluoreszenzspektroskopische Untersuchungen zeigten, dass Uran im Biofilm reduziert wurde.

L'objectif de ce travail est de développer un système catalytique hétérogène pour l'époxydation en utilisant directement O2 de l'air plutôt que H2O2 commercial. La stratégie adoptée a été de coupler la production in situ de H2O2, catalysée par la glucose oxydase (GOx), avec un catalyseur à base de Ti. La GOx a été immobilisée de manière covalente sur une mousse silicique mesocellulaire (MCF) amino-fonctionnalisée puis la stabilité thermique et aux solvants organiques de MCF-NH2-GOx a été étudiée. L'approche visant à ancrer Ti puis la GOx sur le même support n’a pas abouti à un catalyseur tandem efficace du fait d'un recouvrement de Ti par –NH2. L’hydrophilie de MCF apparaît, de plus, défavoriser l'oxydation d'alcènes organosolubles. Une option a consisté à utiliser la zéolithe TS-1 hydrophobe et réputée fonctionner en milieu aqueux mais dont les micropores ne peuvent loger la GOx. Cette dernière, associée à MCF-NH2-GOx en mélange mécanique, s’est montrée performante pour l'oxydation du cyclohexène dans MeOH/tampon acétate 50:50 à 35°C (rendement de 50% en époxyde et ses dérivés). D’encore meilleurs résultats ont été obtenus pour le prop-2-ène-1-ol en milieu aqueux à 40°C (rendement de 87% en glycérol). L’attaque basique de TS-1 crée une porosité suffisante pour loger la GOx, mais endommage son activité. En revanche, le recouvrement de MCF par un film de TS-1 a eu un effet bénéfique sur l’oxydation du prop-2-ène-1-ol dans l’eau par H2O2. Enfin, la porphyrine Mn-TCPP s’est montrée efficace comme catalyseur d'oxydation en tandem avec la GOx en solution mais, en cas d’immobilisation sur le support silicique MCF, la formation d’un précipité inhibe son activité. / The objective of this work was to develop an heterogeneous catalyst system supplied by dioxygen, rather than commercial H2O2, in order to carry out epoxidation reactions. Our strategy was to couple the in situ production of H2O2, catalyzed by glucose oxidase (GOx), with a Ti-based catalyst. The enzyme was covalently grafted onto a silicic mesocellular foam (MCF) functionalized by aminopropyle groups, then the thermal stability and behavior in organic solvents of the resulting material were investigated. The approach aiming at anchoring Ti, then GOx on the same support did not result in an effective tandem catalyst because of a too high –NH2 surface coverage. Hydrophilicity of MCF makes the oxidation of organosoluble alkenes unefficient. An alternative approach consisted in using the hydrophobic TS-1 zeolite known to operate in aqueous medium but whose micropores do not allow GOx hosting. However, TS-1 combined in a mechanical mixture with GOX immobilized on MCF turned out to be effective for the oxidation of cyclohexene in MeOH/acetate buffer 50:50 at 35°C (50% yield of epoxide and its derivatives). Even better performances were obtained for prop-2-ene-1-ol oxidation in aqueous medium at 40°C (87 % yield of glycerol). The basic attack of TS-1 has created mesoporosity to host GOx but damaged active Ti sites. On the other hand, TS-1 coated MCF appeared to be a good option having a beneficial effect on the oxidation of prop-2-en-1-ol in water by H2O2. Finally, a manganese porphyrin, Mn-TCPP, was also tested successfully as alkene oxidation catalyst in combination with GOx but, in case of immobilization, the presence of the silicate support lead to a deactivated catalyst.

Plasma polymerization techniques were used to synthesize and deposit hydrogel on silicon (Si) substrate. Hydrogel is a network of polymer chains that are water-insoluble and has a high degree of flexibility. The various fields of applications of hydrogel include drug release, biosensors and tissue engineering etc. Hydrogel synthesized from different monomers possess a common property of moisture absorption. In this work two monomers were used namely 1-amino-2-propanol (1A2P) and 2(ethylamino)ethanol (2EAE) to produce polymer films deposited on Si ATR crystal. Their moisture uptake property was tested using FTIR-ATR technique. This was evident by the decrease in -OH band in increasing N2 purging time of the films. Secondly, two monomer compounds namely vinyl acetic acid and glycidyl methacrylate which have both amine and carboxylic groups are used as solid surface for the immobilization of bovine serum albumin (BSA). Pulsed plasma polymerization was used to polymerize these monomers with different duty cycles. Initial works in this field were all about protein surface adsorption. But more recently, the emphasis is on covalent bonding of protein on to the surface. This immobilization of protein on solid surface has a lot of applications in the field of biochemical studies. The polymerization of vinyl acetic acid and glycidyl methacrylate were shown as successful method to attach protein on them. Chemical mechanical polishing (CMP) of Cu is one of the processes in the integrated chips manufacturing industry. Benzotriazole is one of the constituents of this CMP slurry used as corrosion inhibitor for Cu. Benzotriazole (C6H5N3) is a nitrogen heterocyclic derivative having three nitrogen atoms, each with an unshared pair of electrons, forming five-membered ring structure. This molecule coordinates with Cu atoms by loosing a proton from one of its nitrogen atom and thereby forming a film which is polymeric in nature that prevents further oxidation of Cu. In this work, aqueous solution of BTA was used to study the adsorption characteristics on Cu when a Cu electrodeposited Si was immersed in to it. This study was performed using ATR-FTIR technique. The adsorption of BTA on Cu surface was evident by the presence of aryl C-H stretching band at 3061 cm-1.

Fruto-oligossacarídeos (FOS) são fibras prebióticas com poder adoçante considerável, sendo um produto de alto valor para a indústria de alimentos. Açúcar invertido é o produto da hidrólise da sacarose possuindo maior poder adoçante, menor susceptibilidade à cristalização e maior higroscopicidade com relação à sacarose, sendo de grande interesse industrial. Ambos produtos podem ser produzidos por reações enzimáticas, utilizando β-frutosiltransferase e β- frutofuranosidase respectivamente, no entanto processos enzimáticos costumam ser caros devido ao alto custo e baixa estabilidade de enzimas. Esses fatores podem ser contornados com a imobilização da enzima, permitindo a reutilização e por vezes aumentando a estabilidade. No presente trabalho a enzima β-frutosiltransferase proveniente de um extrato comercial de Aspergillus aculeatus (Viscozyme L) foi parcialmente purificada, com resina de troca iônica, imobilizada covalentemente em esferas de quitosana e utilizada na produção de FOS. O processo de purificação aumentou a atividade específica em 6 vezes. A estabilidade do biocatalisador imobilizado foi avaliada em 50 bateladas para produção de FOS, foi observado cerca de 55 % de rendimento em cada batelada, sem perda de atividade detectada após as utilizações. Após esse experimento foi testada a utilização das esferas em reatores contínuos com leito fixo e fluidizado, com rendimentos de 59 % e 54 % respectivamente. A produção de açúcar invertido foi feita utilizando a enzima Maxinvert L (β-frutofuranosidase de Saccharomyces cerevisiae) que foi imobilizada, da mesma forma, em esferas de quitosana e sua utilização foi testada em reatores de leito fixo e fluidizado com rendimentos de 98 % e 94 % respectivamente. Os reatores de leito fixo possuem potencial para estudos envolvendo aplicações industriais tanto para produção de FOS quanto para produção de Açúcar Invertido. / Fructooligosaccharides (FOS) are prebiotic fibre with sweetening power, being a highvalue product for the food industry. Invert sugar is the product of sucrose hydrolysis; it has a higher sweetening power, it is less susceptible to crystallization and has a higher hygroscopicity than regular sugar. Finding many uses in food industry processes. Both products can be obtained by enzymatic reactions using β-fructosyltransferase and β- fructofuranosidase, respectively. However, enzymatic processes are often costly because of high enzymatic cost and lack of operational stability. These drawbacks can be overcome by immobilization of enzyme, enabling reuses and usually increasing its stability. In the present work, β-fructofuranosidase from a commercial preparation from Aspergillus aculeatus (Viscozyme L) was partially purified, covalently immobilized on chitosan spheres and used for FOS production. Partial purification resulted in a 6-fold increase in specific activity. Operational stability of biocatalyst was evaluated along 50 batches, resulting in around 55 % yield on each batch and no loss of activity after batches. The immobilized biocatalyst was also used for FOS production in packed bed and fluidized bed reactors with yields of 59 % and 54 % respectively. Invert sugar production was carried out using Maxinvert L (β- fructofuranosidase from Saccharomyces cerevisiae) immobilized, by the same method, on chitosan spheres. Its application on packed bed and fluidized bed reactors was evaluated resulting in yields of 98 % and 94 % respectively. The packed bed reactors presented potential for further studies aiming industrial applications for FOS and Invert Sugar production.

O objetivo deste estudo foi avaliar a influência da irradiação a laser de baixa intensidade, associada ou não a imobilização, nas propriedades mecânicas do músculo gastrocnêmio submetido a lesão experimental por mecanismo de impacto. Foram utilizadas 70 ratas da variedade Wistar, divididas em 7 grupos experimentais: grupo controle; grupo lesão; grupo lesão irradiação laser; grupo lesão-imobilização 24 horas-irradiação laser; grupo lesão-imobilização 72 horas-irradiação laser; grupo lesão-imobilização 24 horas; grupo lesão-imobilização 72 horas. A lesão foi provocada no músculo gastrocnêmio por mecanismo de impacto (trauma direto não invasivo). Os músculos foram submetidos a ensaios mecânicos na máquina universal de ensaio EMIC e, por meio da interface com microcomputador, geraram gráficos carga x alongamento a partir dos quais foram calculadas as respectivas propriedades mecânicas: carga e alongamento no limite de proporcionalidade e no limite máximo e rigidez. A lesão provocou diminuição da carga no limite de proporcionalidade e no limite máximo em relação ao grupo controle (p < 0,05). Os grupos submetidos a imobilização por 24 e 48 horas respectivamente e irradiados não apresentaram melhora das propriedades avaliadas quando comparados ao grupo lesão (p < 0,05). A análise mecânica mostrou que a lesão muscular foi efetiva e que a associação de imobilização gessada e irradiação laser não foi efetiva na melhora das propriedades mecânicas avaliadas / The aim of this study was to evaluate the influence of low power laser irradiation, associated or not with immobilization, on the mechanical properties of a gastrocnemius muscle submitted to experimental injury caused by impact mechanism. Seventy Wistar rats were used, and were divided into 7 experimental groups: 1-control group; 2-injury group; 3-injury–laser irradiation group; 4-injury–24 hour immobilization–laser irradiation group; 5-injury–72 hour immobilization–laser irradiation group; 6-injury–24 hour immobilization group; 7-injury–72 hour immobilization group. Injury was caused in the gastrocnemius muscle through impact mechanism (non-invasive direct trauma). Muscles were submitted to mechanical tests in the EMIC machine, and using computer interface they generated load x deformation graphs from which the mechanical properties of load and stretch were calculated: at the limit of proportionality, at the maximum limit and stiffness. The injury reduced load at the limit of proportionality and at the maximum limit in relation to control group (p < 0,05). Groups that were submitted to 24 and 48 hour immobilization respectively and were irradiated showed no improvement in the evaluated properties when compared to injury group (p < 0,05). A mechanical analysis showed that the muscular injury was effective, and that the association of plaster cast immobilization with irradiation was not efficient to improve the evaluated mechanical properties

O músculo esquelético é bastante adaptável às alterações nas demandas funcionais. Este trabalho teve como objetivo analisar o treinamento físico com natação, o sedentarismo e os efeitos da imobilização e reabilitação aquática em propriedades mecânicas do músculo gastrocnêmio de ratas treinadas e sedentárias. Para tanto, foram utilizadas 70 ratas Wistar, divididas em 7 grupos experimentais: grupo 1 (Controle) - mantido por 6 semanas em condições basais; grupo 2 (Treinado) - submetido a natação (treinamento de resistência) durante 6 semanas; grupo 3 (Sedentário) - alojado por 6 semanas em gaiolas nas quais a mobilidade esteve limitada; grupo 4 (Treinado-Imobilizado) - treinado com natação e submetido a imobilização gessada por 1 semana; grupo 5 (Sedentário-Imobilizado) - submetido ao sedentarismo e imobilizado por 1 semana; grupo 6 (Treinado-Imobilizado Reabilitado) - submetido a treinamento, imobilizado 1 semana e reabilitado com natação por 2 semanas; grupo 7 (Sedentário-Imobilizado Reabilitado) - mantido sedentário, imobilizado 1 semana e reabilitado com o mesmo protocolo do grupo anterior. Após estas etapas, os animais foram submetidos à eutanásia e o músculo gastrocnêmio do membro pélvico direito foi retirado para a realização do ensaio mecânico de tração em uma máquina universal de ensaios(EMIC). A partir dos gráficos carga versus alongamento de cada ensaio, foram calculadas as seguintes propriedades mecânicas: carga no limite de proporcionalidade, carga no limite máximo e rigidez. Os resultados sugeriram que o treinamento com natação causou adaptações biomecânicas favoráveis no músculo esquelético, ao contrário do sedentarismo. A imobilização gessada acarretou piora das propriedades mecânicas analisadas e, embora a perda em valores absolutos tenha sido maior nos animais submetidos ao treinamento prévio, houve maior preservação das propriedades dos músculos nas ratas treinadas em comparação às sedentárias. Além disto, a reabilitação foi eficiente em melhorar o comportamento mecânico muscular e foi possível observar que os animais previamente treinados apresentaram resultado final mais satisfatório que os sedentários / The skeletal muscle is a very adjustable structure and may present changes in response to functional demands. The aim of this study was to investigate the influence of physical training (swimming), sedentarism and the effects of immobilization and aquatic rehabilitation on the mechanical properties of the gastrocnemius muscle of trained and sedentary rats. Seventy female Wistar rats were allocated into seven experimental groups: group 1 (Control) - kept during 6 weeks in basal conditions; group 2 (Trained) - conditioned by a swimming program (resistance training) during six weeks; group 3 (Sedentary) - kept, during the same period, in small cages in which their mobility was restricted; group 4 (Trained-Immobilized) – previously trained with swimming and immobilized in a spica cast during a week; group 5 (Sedentary-Immobilized) - submitted to sedentarism and immobilized during a week; group 6 (Trained-Immobilized-Rehabilitated) physically trained, immobilized during a week and rehabilitated with swimming during two weeks; group 7 (Sedentary-Immobilized- Rehabilitated) - submitted to sedentarism, immobilized during a week and rehabilitated with the same protocol of the previous group. After this period, the animals were killed and the right gastrocnemius muscle was collected and mechanically tested in traction in a standard testing machine (EMIC). From the load versus deformation curves, the following mechanical parameters were obtained: load in the yield limit, ultimate load and stiffness. The results suggest that physical training caused favorable mechanical adaptations in the striated muscle. Conversely, sedentarism yielded a decrease in the mechanical parameters. Cast immobilization induced a decrease of mechanical parameters and, although the decrease was greater animals submitted to previous training, the mechanical parameters of trained rats were preserved in comparison to the sedentary animals. In addition, the rehabilitation program improved the muscular mechanical behavior and the previously trained animals showed a better recovery when compared with the sedentary rats

Avaliamos a influência da imobilização, remobilização livre, remobilização com alongamento passivo manual, remobilização com estimulação elétrica neuromuscular (EENM) e remobilização com estimulação elétrica e alongamento passivo associados sobre algumas propriedades mecânicas do músculo gastrocnêmio de ratas. Foram utilizadas 60 ratas albinas da variedade Wistar e divididas em 6 grupos experimentais. Um grupo foi utilizado como controle. Cinco grupos tiveram o membro posterior direito imobilizado por 14 dias consecutivos. Destes 5 grupos um foi submetido à morte logo após o período de imobilização, um foi liberado da imobilização permanecendo em gaiolas plásticas por 10 dias, outro foi submetido a técnica de alongamento passivo manual por 10 dias consecutivos, outro foi submetido a EENM por 10 dias consecutivos e o último foi submetido a EENM somado ao alongamento passivo manual por 10 dias consecutivos. Após os períodos de intervenção os animais foram mortos e em seguida realizados os ensaios mecânicos de tração longitudinal dos músculos. As propriedades mecânicas avaliadas foram a carga e alongamento no limite de proporcionalidade e no limite máximo, a rigidez e a capacidade de absorver energia na fase elástica (resiliência) do músculo, obtidas a partir das curvas carga versus alongamento. Observamos que a imobilização provocou redução significativa nos valores das propriedades mecânicas avaliadas no músculo gastrocnêmio. A remobilização por alongamento passivo manual devolveu ao músculo as propriedades de alongamento no limite de proporcionalidade, rigidez e resiliência a padrões controle, entretanto não foi capaz de restabelecer as propriedades de carga no limite de proporcionalidade, carga e alongamento no limite máximo. A remobilização constituída por EENM restabeleceu todas as propriedades estudadas a padrões controle. A remobilização por estimulação elétrica somada ao alongamento passivo restabeleceu as propriedades mecânicas de alongamento no limite máximo e de proporcionalidade e rigidez, no entanto não foi capaz de devolver ao músculo suas propriedades carga no limite máximo, carga no limite de proporcionalidade e resiliência. A remobilização livre não foi capaz de restabelecer nenhuma das propriedades a padrões controle / We evaluated the influence of immobilization, free remobilization, remobilization with manual passive stretching, remobilization with neuromuscular electric stimulation (NMES) and remobilization with electric stimulation and passive stretching associated upon some mechanical properties of the gastrocnemius muscle of female rats. We used sixty female albinic rats of the variety Wistar and divided them in 6 experimental groups. One of these groups was used as control. The animals of the five other groups had their right hind immobilized for 14 consecutive days. From the five groups, one was submitted to death right after the immobilization period, a second was set free from the immobilization remaining in plastic cages for 10 days, a third was submitted to the manual passive stretching technique for 10 consecutive days, a fourth was submitted to NMES for 10 consecutive days and the last one was submitted to NMES and manual passive stretching for 10 consecutive days. After the intervention periods, the animals were submitted to death and afterwards the mechanical tests of longitudinal traction of the muscles were done. The mechanical properties evaluated were the load and the stretching in the limit of proportionality and in the maximum limit, the stiffness and the capacity to absorb energy in the elastic phase (resilience) of the muscle, obtained based on the curves load versus stretching. We observed that the immobilization has provoked significant reduction of the values of the mechanical properties evaluated in the gastrocnemius muscle. The remobilization by the manual passive stretching gave back to the muscle the mechanical properties of stretching in the limit of proportionality, stiffness and resilience like the standard ones of the control group, but it was not capable of reestablishing the properties of load in the limit of proportionality, load and stretching in the maximum limit. The remobilization done by the NMES reestablished all of the properties studied like ones of the control group. The remobilization by electric stimulation and passive stretching reestablished the mechanical properties in the maximum limit and in the proportionality and stiffness, although it was not capable of giving back to the muscle its properties of load in the maximum limit, load in the limit of proportionality and resilience. The free remobilization was not capable of reestablish any of the properties like the ones of the control group