O interesse em efeitos sinérgicos ou antagônicos através de experiências com associações cresceu imensamente nas últimas décadas. Com o objetivo de estudar a associação de dois herbicidas inibidores da ALS (sulfometuron-methyl e chlorimuron-ethyl) em Digitaria insularis, empregou-se dos métodos estatísticos fornecidos por meio das curvas dose-resposta e isobologramas. O conceito de curvas dose-resposta tem sido amplamente utilizado para avaliar os resultados das experiências com herbicidas. No entanto, a abordagem estatística em torno das curvas deve ser cuidadosa; cosiderar as curvas dose-resposta semelhantes quando elas não são pode influenciar muito na comparação entre as moléculas e afetar o cálculo da potência relativa. A potência relativa ajuda a entender qual é a relação de potência entre as moléculas, esse conhecimento é fundamental para os estudos com os herbicidas em associação. Sabendo-se disso foram conduzidos experimentos do tipo dose-resposta em dois tipos de substratos utilizando Digitaria insularis como planta daninha indicadora. Os experimentos foram conduzidos em casa de vegetação do Centro de Pesquisa e Desenvolvimento da DuPont em Paulínia (SP). Para cada molécula foram aplicadas, em pré-emergência, oito doses com quatro repetições cada e quatro plantas testemunha nos diferentes substratos. O substrato A é somente substrato comercial (marca Tropstrato HT®) puro; E o substrato B é uma mistura de solo arenoso, peneirado e livre de contaminação mais substrato comercial na proporção 3:1 v/v. Neste caso ficou evidente a maior capacidade do sulfometuronmethyl em reduzir a biomassa da espécie, as curvas dose-resposta foram descritas pelo modelo log-logístico com os valores de ED50 e as declividades de cada curva variando livremente, pois as hipóteses testadas nos diferentes substratos de curvas paralelas foram rejeitadas. O valor calculado da potência relativa para o nível de resposta de 50% entre os herbicidas CLASSIC® (chlorimuron-ethyl) e CURAVIAL® (sulfometuron-methyl) nas condições desse estudo foi de 8,596 e 44,047 nos Substrato A e B respectivamente. A partir dessa informação foram utilizadas as mesmas condições do experimento anterior para o experimento com as isoboles dos herbicidas em associação, cinco curvas dose-resposta, foram propostas, duas curvas para os produtos isolados e três curvas para as associações em diferentes proporções [(25% : 75%); (50% : 50%); (75% : 25%)] chlorimuron-ethyl / sulfometuron-methyl, totalizando 144 parcelas. Vários modelos isoboles foram testados, o modelo de Concentração Aditiva foi significativamente descartado, mas foi levado em consideração para testar teoricamente o grau de sinergia ou antagonismo que modelos mais complexos podiam fornecer. O modelo de isobole proposto por Hewlett e Plackett (1959) teve ajuste significativo e parâmetro de interação menor que um (λ=0,33). O modelo que mais se ajustou aos dados foi o proposto por Vølund e os resultados também mostraram que nessas condições a associação de sulfometuron-methyl com chlorimuron-ethyl foi antagônica; as isoboles são potentes ferramentas para capturar e descrever associações de herbicidas. Entretanto a literatura mostra que associar duas moléculas e testar em um sistema biológico complexo sofrendo variações das diferentes condições ambientais possíveis pode gerar respostas variáveis, portanto esses resultados devem ser repetidos em outras condições para validar as conclusões ou então serem executados em condições controladas de laboratório e usar organismos vivos de menor complexidade como bioindicador. / The interest in synergistic or antagonistic effects through experiences with associations has immensely grown in recent decades. In order to study the association of two ALS inhibitor herbicides (sulfometuron-methyl and chlorimuronethyl) in Digitaria insularis, the statistical methods provided by the dose-response curves and isobolograms were used. The concept of dose-response curves has been widely used to evaluate the results of herbicide experiments. However, the statistical approach around curves must be careful; considering the dose-response curves when they are not can greatly influence the comparison between molecules and affect the calculation of relative potency. Relative potency helps to understand what the power ratio is between molecules, this knowledge is fundamental for studies with herbicides in association. Knowing this, dose-response experiments were conducted on two types of substrates using Digitaria insularis as an indicator weed. The experiments were conducted in a greenhouse of the DuPont Research and Development Center in Paulínia (SP). For each molecule were applied, in pre-emergence, eight doses with four replicates each and four control plants on different substrates. Substrate A is pure commercial substrate (brand Tropstrato HT®); and substrate B is a mixture of sandy soil, sifted and contamination-free plus commercial substrate in the ratio 3:1 v/v. In this case it was evident the greater capacity of the sulfometuron-methyl to reduce the biomass of the species, the dose-response curves were described by the log-logistic model with the values of ED50 and the slopes of each curve varying freely, since the hypotheses tested in the different substrates of parallel curves were rejected. The calculated value of relative potency for the 50% response level between CLASSIC® (chlorimuron-ethyl) and CURAVIAL® (sulfometuron-methyl) herbicides under the conditions of this study was 8.596 and 44.047 on Substrate A and B respectively. From this information the same conditions of the previous experiment for the isoboles of the herbicides in association were used, five doseresponse curves were proposed, two curves for the isolated products and three curves for the associations in different ratios [25% : 75%); (50% : 50%); (75% : 25%)] chlorimuron-ethyl / sulfometuron-methyl, totaling 144 plots. Isoboles models were tested, the Concentration Additive model was significantly discarded, but was taken into account to theoretically test the degree of synergy or antagonism that more complex models could provide. The isobole model proposed by Hewlett and Plackett (1959) had a significant adjustment and interaction parameter smaller than 1 (λ = 0.33). The model that best fit the data was the one proposed by Vølund and the results also showed that under these conditions the association of sulfometuronmethyl with chlorimuron-ethyl was antagonistic; isoboles are potent tools for capturing and describing herbicide associations. So these results must be repeated in other conditions to validate the conclusions or to be executed in controlled laboratory conditions and to use living organisms of lesser complexity as a bioindicator.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / The Lippia alba (Mill.) N. E. Brown species inhabits almost all regions of Brazil, which is plenty used in popular medicine. Studies show that between the Brazilian Northeast three chemotypes of L. alba, the chemotype II (OELaII), produces in its leaves, essential oil with the largest and broadest antimicrobial potential. The objective of this study was to evaluate the interference of the OELaII in the Oxacillin activity and its mechanism of action against Staphylococcus aureus. The antimicrobial activity was performed by determining the Minimum Inhibitory Concentration (MIC) and minimum bactericidal concentration (MBC) by broth microdilution methods of culture and spreading on the surface of agar Plate-Count, respectively. The evaluation of the OELaII interference on antimicrobial oxacillin activity and other antibiotics was performed by using methodology changed disk diffusion. The checkerboard method, calculation of Fractional Inhibitory Concentration Indices and graphing Isobologramas was used to assess the interference OELaII the antimicrobial activity oxacillin. The study of the OELaII mechanism of action on strains of S. aureus was performed by evaluating the OE antimicrobial activity in the phases of exponential growth and stationary as well as by the action of chloramphenicol on the exponential growth. The effect of OELaII, oxacillin and OELaII-OXA exposure time, on strains of S. aureus was observed by tracing curves time of death, was considered synergistic association was found that a reduction in the number of viable cells after 24-48 hours when compared to each compound alone. The results revealed that the MIC and MBC OELaII to the strains of S. aureus oxacillin resistant (ORSA) are equal or very close to those observed for susceptible strains (UR) ranging from 0.312 to 1.25 mg / ml and 1.25 to 5.0 mg / mL for the first, and 0.312 -0.625 mg / mL and 0.625 to 2.5 mg / mL for the second. Oxacillin to the values obtained were 6.25 to 200 mg / ml and 25 and 400 mg / mL and 0.390 to 3.12 for ORSA mg / mL and 0.781 to 6.25 mg / mL for the UR. The study of the evaluation of synergism using the Kirby-Bauer method and checkerboad showed that the interference exerted by the essential oil on the antimicrobial action vary with the type of antibiotic and the type of strain tested. Isobologram charts obtained by checkerboard method suggests a synergism between good and OELaII Oxacillin for all the microorganisms tested. The study of the mechanism of action on inhibition OELaII /death ORSA strains, it was found that the OELaII reduced the number of viable cells in any growth stage. The same was not observed when cell division was halted by the presence of chloramphenicol, suggesting that OE acts mainly in the exponential growth phase (intense cell division). The death curve by microbial activity and OELaII Oxacillin showed a synergistic effect for the association OELaII-OXA, with a logarithmic decrease significantly when compared to treatment done alone. Given this biological potential, this study suggests that the Lippia alba can be used as a pharmaceutical ingredient in preparations of association with antimicrobial drugs in order to diminish the toxicity and increase its spectrum. However, there is the importance of studies on the elucidation of the different molecular targets through knowledge of its mechanism of action and toxicity testing in vitro, thus providing the safety and therapeutic efficacy of this important plant species users. / A espÃcie Lippia alba (Mill.) N. E. Brown habita praticamente todas as regiÃes do Brasil, onde à muito empregada na medicina popular. Estudos mostram que, entre os trÃs quimiotipos de L. alba do Nordeste Brasileiro, o quimiotipo II (OELaII), produz, em suas folhas, o Ãleo essencial com o maior e mais amplo potencial antimicrobiano. O objetivo deste estudo foi avaliar a interferÃncia do OELaII na atividade de Oxacilina e o seu mecanismo de aÃÃo frente a cepas de Staphylococcus aureus. A avaliaÃÃo da atividade antimicrobiana foi realizada pela determinaÃÃo da ConcentraÃÃo InibitÃria MÃnima (CIM) e ConcentraÃÃo Bactericida MÃnima (CBM), pelos mÃtodos de microdiluiÃÃo em caldo de cultura e espalhamento na superfÃcie do Ãgar Plate-Count, respectivamente. A avaliaÃÃo da interferÃncia do OELaII na atividade antimicrobiana da Oxacilina e outros antibiÃticos de uso foi realizada pela metodologia de disco-difusÃo modificado. O mÃtodo de Checkerboard, cÃlculo dos Indices da ConcentraÃÃo InibitÃria Fracionada e construÃÃo de grÃficos Isobologramas foi utilizado na avaliaÃÃo da interferÃncia do OELaII na atividade antimicrobiana da Oxacilina. O estudo do mecanismo de aÃÃo do OELaII sobre cepas de S. aureus foi realizado pela avaliaÃÃo da atividade antimicrobiana do OE nas fases de crescimento exponencial e estacionÃrio, bem como pela aÃÃo do cloranfenicol sobre o crescimento exponencial. O efeito do tempo de exposiÃÃo ao OELaII, Oxacilina e OELaII-OXA sobre cepas de S. aureus foi verificado pelo traÃado das curvas de tempo de morte, sendo considerado sinergismo as associaÃÃes em que foi verificado uma reduÃÃo do nÃmero de cÃlulas viÃveis, apÃs 24-48 horas quando comparado a cada composto isoladamente. Os resultados obtidos revelaram que a CIM e CBM do OELaII para cepas de S. aureus oxacilina-resistente (ORSA) sÃo iguais ou muito prÃximas Ãquelas constatadas para as cepas sensÃveis (OSSA), variando de 0,312-1,25 mg/mL e 1,25-5,0 mg/mL para a primeira; e 0,312-0,625 mg/mL e 0,625-2,5 mg/mL para a segunda. Para a Oxacilina os valores encontrados foram de 6,25-200 mg/mL e 25 e 400 mg/mL para as ORSA e 0,390-3,12 mg/mL e 0,781-6,25 mg/mL para as OSSA. O estudo da avaliaÃÃo do sinergismo, pelo mÃtodo de Kirby-Bauer e por checkerboad, mostrou que a interferÃncia exercida pelo Ãleo essencial sobre a aÃÃo dos antimicrobianos varia de acordo com o tipo de antibiÃtico e o tipo de cepa testada. Os grÃficos de isobolograma obtidos pelo mÃtodo de checkerboard sugerem um bom sinergismo entre o OELaII e a Oxacilina para todos os micro-organismos testados. Pelo estudo do mecanismo de aÃÃo do OELaII na inibiÃÃo/morte de cepas ORSA, verificou-se que o OELaII reduziu o nÃmero de cÃlulas viÃveis em qualquer estÃgio de crescimento. O mesmo nÃo foi verificado quando a divisÃo celular foi interrompida pela presenÃa de cloranfenicol, sugerindo que o OE age, principalmente, na fase exponencial de crescimento (intensa divisÃo celular). A curva de morte microbiana pela atividade do OELaII e Oxacilina, mostrou um efeito sinÃrgico para a associaÃÃo OELaII-OXA, com uma reduÃÃo logarÃtima significativa, quando comparado ao tratamento feito isoladamente. Diante desse importante potencial biolÃgico, este estudo sugere que a Lippia alba possa ser utilizado como insumo farmacÃutico em preparaÃÃes de associaÃÃo com medicamentos antimicrobianos visando a diminuir a toxicidade e aumentar o seu espectro de aÃÃo. Todavia, surge a importÃncia de estudos sobre a elucidaÃÃo dos diferentes alvos moleculares atravÃs do conhecimento do seu mecanismo de aÃÃo, bem como testes de toxicidade in vitro, oferecendo assim, seguranÃa e eficÃcia terapÃutica aos usuÃrios dessa importantes espÃcie vegetal

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-05-25T18:14:33Z No. of bitstreams: 1 Resumo-MarliseMilhomem.pdf: 42297 bytes, checksum: 30c042f85d9be42768eb80b841807673 (MD5) / Made available in DSpace on 2017-05-25T18:14:33Z (GMT). No. of bitstreams: 1 Resumo-MarliseMilhomem.pdf: 42297 bytes, checksum: 30c042f85d9be42768eb80b841807673 (MD5) Previous issue date: 2017-04-04 / The Rhipicephalus microplus tick is considered one of the biggest problems for cattle breeding in Brazil. The continuous use of synthetic acaricides to control this tick has increased the frequency of resistance. Work using extracts and plant oils, are shown to be promising in the control of R. microplus. Lippia gracilis is a plant rich in essential oil, presenting major compounds which have a proven carrapaticide effect. The objective of this work was to evaluate the effect of the association between synthetic carrapaticides and natural compounds on resistant and susceptible synthetic Rhipicephalus microplus larvae. Immersion tests of R. microplus larvae were carried out using synthetic carrapaticides and essential oils (OE) of L. gracilis and their major compounds. First the lethal concentration to 50% (LC50) of the larvae was found for each of the isolated compounds. Associations of each of the natural compounds associated with a synthetic carrapaticides. In the obtained results it is observed that there was an antagonistic effect in the associations with one of the synthetic carrapaticides used, however in the associations with the other carrapaticide a strong synergic effect is observed, the same occurred for the two strains. We have shown that associations of natural compounds with synthetic carrapaticides may be a promising alternative in the control of R. microplus / O carrapato Rhipicephalus microplus é considerado um dos maiores problemas para a pecuária bovina no Brasil. O uso contínuo de acaricidas sintéticos para o controle deste carrapato tem aumentado a frequência de resistência. Trabalhos utilizando extratos e óleos de plantas, mostram-se promissores no controle do R. microplus. Lippia gracilis é uma planta rica em óleo essencial, apresentando compostos majoritários os quais tem comprovado efeito carrapaticida. O objetivo deste trabalho foi avaliar o efeito da associação entre carrapaticidas sintéticos e compostos naturais sobre larvas de Rhipicephalus microplus resistentes e sensíveis a compostos sintéticos. Foram realizados testes de imersão de larvas de R. microplus, utilizando carrapaticidas sintéticos e óleo essencial (OE) de L. gracilis e seus compostos majoritários. Primeiramente encontrou-se a concentração letal para 50% (CL50) das larvas para cada um dos compostos isolados. Em seguida foi realizada associações de cada um dos compostos naturais associado a um carrapaticida sintético. Nos resultados obtidos observase que houve efeito antagônico nas associações com um dos carrapaticidas sintéticos utilizados, no entanto nas associações com o outro carrapaticida observa-se um forte efeito sinérgico, o mesmo ocorreu para as duas cepas. Demonstramos que as associações de compostos naturais com carrapaticidas sintéticos podem ser uma alternativa promissora no controle do R. microplus.

A.baumannii é um importante patógeno em infecções nosocomiais principalmente por sua capacidade de se tornar resistente aos antimicrobianos. Surtos de A.baumannii resistente aos carbapenêmicos (ABRC) têm sido descritos em todo mundo. Devido à emergência de resistência aos antimicrobianos e ausência de novas opções de tratamento, as polimixinas reemergiram como opção de terapia contra infecções causadas por A.baumannii. O uso de polimixina é associado a maior mortalidade e menor eficácia comparada a outros antimicrobianos. Alguns estudos in vitro têm avaliado a combinação de polimixina com outros antimicrobianos a fim de aumentar a eficácia dos tratamentos. O objetivo deste estudo foi avaliar o sinergismo entre a polimixina B com outros antimicrobianos em isolados de ABRC, pelo método de Curvas Tempo-Morte bacteriana (Time- Kill Curves). Os isolados foram provenientes de banco de amostras e foram avaliadas as combinações de polimixina B com carbapenêmicos (imipenem e meropenem), tigeciclina, rifampicina, amicacina e ceftazidima. As combinações foram testadas nos tempo 0, 30’, 1,4,12 e 24 h. Sinergismo entre polimixina B foi demonstrado contra todos antimicrobianos para ambos isolados, exceto para ceftazidima e imipenem no isolado 1. Nosso estudo mostrou que tigeciclina, amicacina e rifampicina são agentes mais ativos combinados com polimixina B, sendo assim estes agentes podem apresentar efeito benéfico em combinação com a polimixina no tratamento de ABRC. / A.baumannii is an important pathogen in nosocomial infections primarily for its ability to become resistant to antimicrobials. Outbreaks carbapenem- resistant A.baumannii (CRAB) has been described worldwide. Due to the emergence of antimicrobial resistance and the absence of new treatment options, the polymyxins reemerged as an option therapy against infections caused by A.baumannii. The use of polymyxin is associated with higher mortality and lower effectiveness compared to other antimicrobials. In vitro studies have evaluated the combination of polymyxin with other antimicrobial agents to enhance the effectiveness of the treatments. This study was to evaluate the synergy between polymyxin B with other antimicrobials in isolates from ABRC, by Time-Kill Curves. The isolates were from stool samples and were evaluated combinations of polymyxin B with carbapenems (imipenem and meropenem), tigecycline, rifampin, amikacin and ceftazidime. The combinations were tested at time 0, 30 ', 1,4,12 and 24 h. Synergism between polymyxin B was demonstrated against all antimicrobials for both isolates, except for ceftazidime and imipenem in isolated 2. Our study showed that tigecycline, amikacin and rifampicin more active agents are combined with polymyxin B, and thus these agents may have a beneficial effect in combination with a polymyxin in treating CRAB.

Nesta dissertação, identificou-se que as drogas esqualestatina, fosmidomicina, risedronato e nerolidol apresentam atividades sinérgicas e aditivas quando administradas em cultura de P. falciparum. Esses resultados contribuem para a compreensão da biologia do parasita e abrem estudos para possíveis antimaláricos. Identificou-se a especificidade da droga esqualestatina inibidora da enzima fitoeno sintase por meio de marcações metabólicas utilizando precursor radioativo ([3H]GGPP), e análise pela técnica de cromatografia (RP-HPLC). Realizou-se testes de inibição para determinar o valor da IC50 na linhagem pRM2-Fito-HA, a qual encontra-se super expressando enzima fitoeno sintase e encontrou-se um valor IC50 de 5 <font face=\"Symbol\">mM para o isolado 3D7 enquanto que para a linhagem pRM2-Fito-HA foi de 30 <font face=\"Symbol\">mM. Demonstrando assim que a enzima fitoeno sintase é o principal, senão único alvo da esqualestatina em P. falciparum, o que sugere que este composto ou derivado do mesmo são potenciais antimalaricos. / In this thesis, we found that the drug squalestatin, fosmidomicina, risedronate, nerolidol have synergistic and additive activity when administered in cultured P. falciparum. These results contribute to the understanding of the biology of the parasite and open studies for potential antimalarials. We identified the specific drug squalestatin inhibiting phytoene synthase enzyme by using metabolic markers radioactive precursor ([3H] GGPP) by the technique of analysis and chromatography (RP-HPLC). Held inhibition tests to determine the IC50 value of the strain in pRM2-Phyto-HA, which is super expressing phytoene synthase enzyme and met an IC50 value of 5 microM to isolate 3D7 whereas for strain pRM2 -Phyto-HA was 30 <font face=\"Symbol\">mM. Thus demonstrating that the enzyme phytoene synthase is the primary, if not sole target of squalestatin in P. falciparum, which suggests that this compound or derivative thereof as potential antimalarials.

Orientador: Ary Fernandes Júnior / Resumo: A busca por novos fármacos é uma constante, especialmente para aqueles obtidos a partir de produtos naturais, que apresentem melhor eficácia e vários efeitos terapêuticos. A própolis e o veneno (apitoxina) da abelha Apis mellifera, além da melitina, uma fração da apitoxina, possuem ação antimicrobiana reportada na literatura. As ações antibacterianas do extrato hidroalcoólico de própolis (EHP), de apitoxinas obtidas das abelhas Apis mellifera submetidas a floras apícolas diferentes (Api 1 - flora apícola silvestre, Api 2 - flora apícola de eucalipto, Api 3 - flora apícola de laranjeira, Api 4 - flora apícola silvestre associada com alimentação artificial) e de melitina foram testadas sobre isolados clínicos de Staphylococcus aureus resistentes à meticilina (MRSA) utilizando metodologia da microdiluição (Resazurin Microtiter Assay Plate – REMA) para obtenção dos respectivos valores de concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM). Ensaios também foram realizados para verificação de sinergismo entre o EHP, as diferentes apitoxinas e a melitina em combinação com a oxacilina sobre uma linhagem de MRSA ATCC e um isolado clínico de MRSA utilizando metodologia da curva de sobrevivência (time kill curve). Foram realizados ensaios inéditos objetivando verificar também se a Api 1 e melitina inibem a produção de enterotoxinas sobre cepas ATCC de S. aureus SEA, SEB, SEC, SED e se inibem a produção de biofilme sobre a cepa ATCC de S. aureus. A microscopia el... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

<p>ABSTRACT</p><p>The purpose of the study was to examine, from the point of view of former research findings, what impact physical activity had on learning. I chose to make an explorative/inductive research, to get as much knowledge as possible from the studied presentation of problem, not to limit myself to a specific research theory. The result proved, that school personal and student experienced many positive effects from daily physical activities. The pupils were more pleased. There was more piece and quiet in the classroom. The ability of concentration increased. The social climate was more agreeable, and with this the developement of knowledge was inpacted. Most research scientists also talked about the importance of better self-reliance and good self-understanding as a result of physical activities. It was also mentioned, that the number of violation had decreased and that the results of the national test had improved. The conclusions were, that it was elementary that schoolboards considered, the alterations in Lpo- and Lpf 94 about daily physical activities, seriously. The leaders of the school area had to appropriate resources, that would make it possible for teachers, to make physical activities form an integral part of many subjects. To sum up, learning was impacted positively by physical activities, even if the reported results showed that further research would be needed.</p> / <p>SAMMANFATTNING</p><p>Syftet med studien var, att utifrån tidigare forskning, undersöka vilken påverkan fysisk aktivitet hade på lärande. Jag valde att göra en explorativ/induktiv undersökning, för att hämta så mycket kunskap som möjligt från det studerade problemområdet och inte begränsa mig till en specifik undersökningsteori. Resultatet visade, att skolans personal och elever upplevde många positiva effekter av daglig fysisk aktivitet. Eleverna var gladare. Det var lugnare i klassrummet. Koncentrationsförmågan ökade. Det sociala klimatet var behagligare, och med det påverkades kunskapsutvecklingen. De flesta forskare nämnde även betydelsen av ökat självförtroende och god självuppfattning, som resultat av fysisk aktivitet. Det framkom också, att antalet kränkningar hade minskat och att resultaten på de nationella proven hade blivit bättre. Slutsatser blev, att det var primärt att skolledning tog förändringarna, i Lpo och Lpf 94, om daglig fysisk aktivitet på allvar. Ledarna i skolans värld borde avsätta mer resurser, som möjliggör för lärare att ämnesintegrera fysisk aktivitet. Sammanfattningsvis, påverkades lärande positivt av fysisk aktivitet, även om resultaten som redovisades visade, att det krävdes ytterliggare forskning.</p>

<p>The enzymatic degradation of cellulose is an important process in nature. This thesis has focused on the degradation of cellulose by enzymes from two cellulose-degrading fungi, <i>Hypocrea jecorina</i> and <i>Phanerochaete chrysosporium</i>, including both the action of the individual enzymes and their synergistic interplay. </p><p>The end-preference of cellobiohydrolases on crystalline cellulose was studied. Cellobiohydrolases belonging to glycosyl hydrolase (GH) family 7 were found to hydrolyse cellulose processively, starting from the reducing end of the cellulose chain. End-labelled cellulose can serve as a tool for functional classification of cellulases.</p><p>The synergy mechanism between endoglucanases and cellobiohydrolases was studied using substrates with different physical properties derived from bacterial cellulose. A new mechanism for synergism between endo- and exoacting enzymes was proposed whereby endoglucanases, in addition to creating nicks in amorphous parts of cellulose, thereby making new starting-points for processively acting cellobiohydrolases, also “polish” the cellulose surface by removing shorter chains from cellulose surface.</p><p>A new small endoglucanase belonging to the GH12 family was isolated and characterised. The proposed role of this enzyme is to make the cellulose in wood more accessible to other cellulases.</p><p>Oxygen conversion by cellobiose dehydrogenase was studied. Hydrogen peroxide produced by cellobiose dehydrogenase can be decomposed even by traces of certain metal ions into a hydroxyl radical and a hydroxyl ion. As an example, reduced metal ions will be continuously regenerated by cellobiose dehydrogenase, which thus stimulates the degradation.</p><p>Interactions between GH7 family cellobiohydrolases and o-nitrophenyl cellobioside were studied by fluorescence spectroscopy and kinetic tests. o-nitrophenyl cellobioside was used as indicator ligand to determine the dissociation constants for cellobiose binding to catalytically inactive Cel7A mutants by displacement binding experiments.</p>

The enzymatic degradation of cellulose is an important process in nature. This thesis has focused on the degradation of cellulose by enzymes from two cellulose-degrading fungi, Hypocrea jecorina and Phanerochaete chrysosporium, including both the action of the individual enzymes and their synergistic interplay. The end-preference of cellobiohydrolases on crystalline cellulose was studied. Cellobiohydrolases belonging to glycosyl hydrolase (GH) family 7 were found to hydrolyse cellulose processively, starting from the reducing end of the cellulose chain. End-labelled cellulose can serve as a tool for functional classification of cellulases. The synergy mechanism between endoglucanases and cellobiohydrolases was studied using substrates with different physical properties derived from bacterial cellulose. A new mechanism for synergism between endo- and exoacting enzymes was proposed whereby endoglucanases, in addition to creating nicks in amorphous parts of cellulose, thereby making new starting-points for processively acting cellobiohydrolases, also “polish” the cellulose surface by removing shorter chains from cellulose surface. A new small endoglucanase belonging to the GH12 family was isolated and characterised. The proposed role of this enzyme is to make the cellulose in wood more accessible to other cellulases. Oxygen conversion by cellobiose dehydrogenase was studied. Hydrogen peroxide produced by cellobiose dehydrogenase can be decomposed even by traces of certain metal ions into a hydroxyl radical and a hydroxyl ion. As an example, reduced metal ions will be continuously regenerated by cellobiose dehydrogenase, which thus stimulates the degradation. Interactions between GH7 family cellobiohydrolases and o-nitrophenyl cellobioside were studied by fluorescence spectroscopy and kinetic tests. o-nitrophenyl cellobioside was used as indicator ligand to determine the dissociation constants for cellobiose binding to catalytically inactive Cel7A mutants by displacement binding experiments.

ABSTRACT The purpose of the study was to examine, from the point of view of former research findings, what impact physical activity had on learning. I chose to make an explorative/inductive research, to get as much knowledge as possible from the studied presentation of problem, not to limit myself to a specific research theory. The result proved, that school personal and student experienced many positive effects from daily physical activities. The pupils were more pleased. There was more piece and quiet in the classroom. The ability of concentration increased. The social climate was more agreeable, and with this the developement of knowledge was inpacted. Most research scientists also talked about the importance of better self-reliance and good self-understanding as a result of physical activities. It was also mentioned, that the number of violation had decreased and that the results of the national test had improved. The conclusions were, that it was elementary that schoolboards considered, the alterations in Lpo- and Lpf 94 about daily physical activities, seriously. The leaders of the school area had to appropriate resources, that would make it possible for teachers, to make physical activities form an integral part of many subjects. To sum up, learning was impacted positively by physical activities, even if the reported results showed that further research would be needed. / SAMMANFATTNING Syftet med studien var, att utifrån tidigare forskning, undersöka vilken påverkan fysisk aktivitet hade på lärande. Jag valde att göra en explorativ/induktiv undersökning, för att hämta så mycket kunskap som möjligt från det studerade problemområdet och inte begränsa mig till en specifik undersökningsteori. Resultatet visade, att skolans personal och elever upplevde många positiva effekter av daglig fysisk aktivitet. Eleverna var gladare. Det var lugnare i klassrummet. Koncentrationsförmågan ökade. Det sociala klimatet var behagligare, och med det påverkades kunskapsutvecklingen. De flesta forskare nämnde även betydelsen av ökat självförtroende och god självuppfattning, som resultat av fysisk aktivitet. Det framkom också, att antalet kränkningar hade minskat och att resultaten på de nationella proven hade blivit bättre. Slutsatser blev, att det var primärt att skolledning tog förändringarna, i Lpo och Lpf 94, om daglig fysisk aktivitet på allvar. Ledarna i skolans värld borde avsätta mer resurser, som möjliggör för lärare att ämnesintegrera fysisk aktivitet. Sammanfattningsvis, påverkades lärande positivt av fysisk aktivitet, även om resultaten som redovisades visade, att det krävdes ytterliggare forskning.