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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Action de la matrice extra-cellulaire sur le métabolisme de l'hépatocyte infecté par le virus de l'hépatice C

Loubert, Jean-Baptiste January 2007 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
82

Efeito da suplementação com L-glutamina e L-alanina, livres ou como dipeptídeo, sobre a lesão, inflamação e citoproteção em modelos de estresse in vivo e in vitro / Effects of supplementation with L-glutamine and L-alanine, in their free form or as dipeptide, on muscle damage, inflammation and cytoprotection of in vivo and in vitro stress models

Raizel, Raquel 10 October 2017 (has links)
Subprojeto 1: Determinação do efeito anti-inflamatório e citoprotetor da suplementação com L-glutamina e L-alanina, ou com L-alanil-L-glutamina (DIP) em ratos submetidos a treinamento resistido. Exercícios intensos reduzem a disponibilidade de glutamina, comprometendo a função imune e a recuperação de atletas. O objetivo do estudo foi avaliar os efeitos da suplementação oral crônica com L-glutamina e L-alanina, nas formas livres ou como dipeptídeo (DIP), sobre parâmetros de lesão, inflamação e citoproteção em ratos Wistar adultos submetidos a treinamento resistido (TR). Neste estudo, o TR reduziu a concentração de glutamina no plasma e no músculo EDL. No entanto, este efeito foi atenuado pelos suplementos contendo L-glutamina, os quais aumentaram os conteúdos da proteína de resposta ao estresse (HSP70) em células do sistema imune (PBMC) e no EDL, concomitantemente à redução da ativação do NF-kB e a da concentração de citocinas no EDL. O efeito protetor das suplementações também foi evidenciado pela atenuação de marcadores de lesão (CK e LDH) e inflamação (TNF-&#945 e IL-1&#946), bem como pelo aumento nas concentrações de marcadores anti-inflamatórios (IL-6, IL-10 e MCP-1) no plasma. Nossos resultados sugerem que a suplementação oral crônica com L-glutamina (administrada com L-alanina livre ou como DIP) promoveu efeitos citoprotetores mediados pela HSP70 em resposta à lesão e inflamação induzidas pelo TR. Subprojeto 2: Efeitos da L-alanil-L-glutamina sobre as vias de sinalização da insulina e da mTOR/S6K, e citoproteção em células musculoesqueléticas C2C12. O dipeptídeo L-alanil-L-glutamina é conhecido por modular o metabolismo e a viabilidade celular. Contudo, os efeitos sobre os componentes clássicos das vias de sinalização da insulina e da mTOR/S6K, bem como o efeito citoprotetor em células musculares, são pouco esclarecidos. O objetivo deste estudo foi investigar o efeito do DIP sobre as vias de sinalização da insulina e da mTOR/S6K em miotubos C2C12, em condições normais ou resistentes à insulina. A exposição crônica à insulina (24h) promoveu resistência à insulina, reduzindo os conteúdos totais do receptor beta (IR-β) e do substrato do receptor de insulina (IRS-1), e diminuindo a fosforilação de IRS-1, AKT e P44/42 MAPK. Adicionalmente, houve redução na expressão do transportador de glicose (GLUT4) e HSP70, redução da viabilidade celular e menor fosforilação de p70S6k e S6, proteínas relacionadas à síntese proteica. Em contraste, a suplementação com DIP aumentou os conteúdos totais de IR-&#946 e IRS-1 e a fosforilação de IRS-1 e AKT. A glicólise anaeróbia e a capacidade glicolítica, além da fosforilação de p70S6k e S6, foram aumentadas pelo DIP em condições normais e na resistência à insulina. Nestas condições experimentais, nossos resultados sugerem que a suplementação com DIP melhorou as vias de sinalizações da insulina e da mTOR/S6K, aumentou a captação e metabolização da glicose, independente da estimulação com insulina e, finalmente, promoveu citoproteção resgatando parcialmente as células de um estado resistente à insulina, por meio do aumento de HSP70 e ativação das etapas finais da via mTOR/S6K. / Subproject 1: Determination of the anti-inflammatory and cytoprotective effects of supplementation with L-glutamine and L-alanine, or with L-alanyl-L-glutamine in rats submitted to resistance training. Intense exercise reduces glutamine availability, compromising immune function and recovery of athletes. The objective of the study was to evaluate the effects of chronic oral supplementation with L-glutamine and L-alanine, in their free form or as dipeptide (DIP), on muscle damage, inflammation and cytoprotection in adult Wistar rats submitted to resistance training (RT). In this study, RT reduced glutamine concentration in plasma and EDL muscle. However, this effect was attenuated by supplements containing L-glutamine, which increased the contents of the stress response protein (HSP70) in immune system cells (PBMC) and EDL, concomitantly with the reduction of NF-kB activation and the concentration of cytokines in EDL. The protective effect of supplementation was also evidenced by attenuation of lesion markers (CK and LDH) and inflammation (TNF-α and IL-1β), as well as by the increase in anti-inflammatory plasma markers (IL-6, IL-10 and MCP-1). Our results suggest that chronic oral supplementation with L-glutamine (administered along with free L-alanine or as DIP) promoted HSP70-mediated cytoprotective effects in response to RT-induced injury and inflammation. Subproject 2: Effects of L-alanyl-L-glutamine on the components of insulin and mTOR/ S6K signaling pathways and cytoprotection in C2C12 musculoskeletal cells. The dipeptide L-alanyl-L-glutamine is known to modulate metabolism and cell viability. However, the effects on the classical components of insulin and mTOR/ S6K signaling pathways, as well as the cytoprotective effect on muscle cells, are poorly understood. The aim of this study was to investigate the effect of DIP on insulin and mTOR/ S6K signaling pathways in C2C12 myotubes, under normal or insulin resistant conditions. Chronic insulin exposure (24h) promoted insulin resistance, reducing the total contents of the insulin receptor (IR-&#946) and the insulin receptor substrate (IRS-1), and decreasing the phosphorylation of IRS-1, AKT and P44/ 42 MAPK. In addition, there was a reduction in the expression of glucose transporter (GLUT4) and HSP70, reduction of cell viability and defective phosphorylation of p70S6k and S6, which are related to protein synthesis. On the other hand, DIP supplementation increased the total contents of IR-&#946 and IRS-1 and the phosphorylation of IRS-1 and AKT. Anaerobic glycolysis and glycolytic capacity, in addition to phosphorylation of p70S6k and S6, were increased by DIP under normal conditions and in insulin resistance. In our experimental conditions, our results suggest that DIP supplementation improved the signaling pathways of insulin and mTOR/ S6K, increased glucose uptake and metabolism, independent of insulin stimulation, and finally promoted cytoprotection by partially rescuing the cells of an insulin resistant state, by increasing HSP70 and activating the final stages of the mTOR/ S6K pathway.
83

Estudo do metaboloma salivar e sua associação com a doença periodontal em pacientes com síndrome de Down / Saliva metabolome in patients with Down syndrome and its association with periodontal disease

Souza, Rafael Celestino de 03 February 2016 (has links)
Os pacientes com Síndrome de Down (SD) possuem grande incidência de doença periodontal (DP), caracterizada por um curso precoce e com maior severidade. O estudo de metaboloma pode contribuir para o entendimento deste curso da doença, identificando possíveis metabólitos como biomarcadores nestes indivíduos. Para entender o perfil metabolômico dos indivíduos com síndrome de Down e a sua relação com a doença periodontal, realizamos a identificação de metabólitos salivares de adolescentes e adultos jovens, entre 12 e 21 anos, ambos os gêneros. Foram coletados dados sobre o estado geral de saúde e realizados exames clínicos bucais, como índice de higiene oral simplificado, sangramento e profundidade de sondagem. Para a análise do metaboloma foi coletada amostra de saliva não estimulada, analisadas por meio de cromatografia gasosa acoplada á espectrometria de massas. Saliva e fluido crevicular gengival também foram coletados para identificação microbiana através do MALDI-TOF. Os dados encontrados foram submetidos a análise estátisca por meio da Análise dos Componentes Principais (PCA) e quantificação relativa dos metabólitos foi avaliada por testes não paramétricos, Mann-Whitney e Kruskal-Wallis. Foi possível observar através dos modelos de PCA separação dos indivíduos com SD e controles, independente da doença periodontal. A quantificação relativa revelou maiores níveis de glicina, lprolina, l-leucina, l-serina, ácido palmítico, ácido pentanóico, ácido tetradecanóico, tirosina e l-fenilalanina nos grupos SD quando comparados aos controles. Controles com DP também apresentaram níveis elevados de glicina, l-alanina, l-serina e manopiranose quando comparados com controles saudáveis. A microbiota de indivíduos com SD apresentous diferenças siginificantes em relação aos individuos controles, principalmente para Rothia dentocariosa, Staphylococcus epidermidis, Tannerella forsythia quando avaliado a saliva e A. Actinomycetemcomitans, Micrococcus luteus, Rothia aeria, Treponema denticola no fluido crevicular gengival. Em conclusão, o perfil metabolômico impresso nos indivíduos com SD difere significativamente dos indivíduos controles, independente da doença periodontal. Entretanto, os metabólitos que diferenciam indivíduos controles com e sem DP, apresentam-se elevados em todos indivíduos com SD, promovendo novos \"insights\" para o perfil metabólico relacionado a DP na SD. / Down Syndrome (DS) patients have a high incidence of periodontal disease (PD), characterized by an early course and greater severity. The metabolome study may contribute to the understanding of the disease course, identifying possible metabolites as biomarkers in these individuals. To understand the metabolomic profile of the DS and their relationship with PD, we conducted the identification of salivary metabolites of adolescents and young adults between 12 and 21 years, both genders. Data were collected on general health and was performed oral clinical examination, as the IHOS, bleeding index and probing depth. For metabolome analysis was collected unstimulated saliva sample, analyzed by gas chromatography coupled to mass spectrometry. Saliva and gingival crevicular fluid were also collected for microbial identification by MALDI-TOF. Data were submitted to analysis-statistic by PCA and relative quantification of metabolites was evaluated by Mann-Whitney and Kruskal-Wallis tests. It can be observed through the PCA models separation of DS groups and controls groups, regardless of periodontal disease. Relative quantification showed higher levels of glycine, L-proline, L-leucine, L-serine, palmitic acid, pentanoic acid, tetradecanoic acid, tyrosine and L-phenylalanine in the SD groups when compared to controls groups. Controls with PD also showed high levels of glycine, L-alanine, L-serine and mannopyranose compared with healthy controls. The microbiota of individuals with DS groups show significant differences compared to control groups, especially for Rothia dentocariosa, Staphylococcus epidermidis, Tannerella forsythia when evaluated saliva and A. actinomycetemcomitans, Micrococcus luteus, Rothia aeria, Treponema denticola in gingival crevicular fluid. In conclusion, the printed metabolomic profile in individuals with Down syndrome differs significantly from control subjects, regardless of periodontal disease. However, the metabolites that distinguish controls group with and without PD, show up high in all DS individuals, promoting new \"insights\" to the metabolic profile related to PD in DS.
84

Estudo térmico e vibracional dos cristais de β-alanina pura e dopada com prata / THERMAL AND VIBRATIONAL STUDY OF β - ALANINE CRYSTALS PURE AND DOPED WITH SILVER

Sousa, Johnny Clécio Feitosa 12 December 2016 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-05-05T20:54:58Z No. of bitstreams: 1 JohnnySousa.pdf: 5039364 bytes, checksum: 4ccdef1692ea6e61c3afd0e3c56d979f (MD5) / Made available in DSpace on 2017-05-05T20:54:58Z (GMT). No. of bitstreams: 1 JohnnySousa.pdf: 5039364 bytes, checksum: 4ccdef1692ea6e61c3afd0e3c56d979f (MD5) Previous issue date: 2016-12-12 / In this work a study on the influence of silver (Ag+ ) in the crystal structure of the crystal β - alanine. The introduction of doping in a crystal lattice can change its physical properties and its growth habit. These changes in the structure can optimize the technological applications of these crystals. The crystals of β - alanine and pure β - alanine doped with silver ions (Ag +) were grown by the method of slow evaporation of solvent resulting in good quality crystals. Characterization was carried measured by X-ray diffraction, thermogravimetry, differential thermal analysis, differential scanning calorimetry and Raman scattering at room temperature and at high temperatures. After twenty days of rest, we obtained the pure and doped crystal growth in a solution with pH 6.2 and 6.8. With the diffractogram of the pure and doped and analyzes the Rietveld method, it was found that at room temperature the β -pure Alanine and doped with Ag + crystallize in the space group of orthorhombic structure P, b, c, a (61) , α, β, γ = 90 °. The refinement of quality parameters were satisfactory, with RWP = 14.32% and S = 1.23 for the pure sample and RWP = 18.16% and S = 1.38. The thermal analysis DTA and TGA showed that pure sample has thermal stability to 180 ° C and a weight loss of 80% between 180ºC and 332ºC with first endothermic event at 202.16 °C. And for the doped mass loss percentage is maintained, but the sample showed a lower thermal stability to 165 ° C first endothermic event at 193.49 ° C. DSC analysis revealed that pure sample undergoes fusion 206.49 ° C and 196.02 ° C in sample doped and that there is no thermal event that features a phase transition before melting. The Raman scattering study was conducted with temperatures in three spectral regions with gradually increasing temperature (40 ° C to 170 ° C). The first 40 cm -1 to 300 cm -1 , corresponding to modes of external vibration the second at 500 cm-1 and 1500 cm-1 and the third at 2800 cm-1 and 3100 cm -1 que are related to the vibration modes internal. The measurements showed that there was a weakening of the intermolecular bonds in the crystal of β - alanine doped with Ag+ ions, and that all the dynamic study is being described by two bands of lower power modes of the network once. Thus, the crystals have good transparency and optical studies can be applied in non-linear optics. / Neste trabalho foi realizado um estudo sobre a influência dos íons (Ag+) na estrutura cristalina do cristal de β – alanina. A introdução de dopantes em uma rede cristalina pode alterar suas propriedades físicas ou seu hábito de crescimento. Estas mudanças na estrutura podem otimizar as aplicações tecnológicas destes cristais. Os cristais de β – alanina pura e β – alanina dopada com íons prata (Ag+) foram crescidos pelo método da evaporação lenta do solvente resultando em cristais de boa qualidade. Medidas de caracterização por difração de raios-X, termogravimetria, análise térmica diferencial, calorimetria exploratória diferencial e espalhamento Raman à temperatura ambiente e a altas temperaturas. Após vinte dias de repouso, obteve-se os cristais puro e dopado em uma solução de crescimento com pH igual a 6.2 e 6.8. Com o difratograma da amostra pura e dopada e as análises do método Rietveld, constatou-se que à temperatura ambiente a β – alanina pura e dopada com Ag+ cristalizam-se numa estrutura ortorrômbica de grupo espacial P,b,c,a (61) , α, β, γ = 90°. Os parâmetros de qualidade do refinamento foram satisfatórios, com Rwp = 14,32% e S = 1,23 para a amostra pura e Rwp = 18,16% e S = 1,38. As análises térmicas de TGA e DTA mostraram que a amostra pura apresenta uma estabilidade térmica até 180ºC e uma perda de massa de 80% entre 180 ºC e 332ºC com primeiro evento endotérmico em 202,16 ºC. E para a amostra dopada os percentuais de perda de massa são mantidos, porém a amostra apresentou uma estabilidade térmica menor, 165ºC com primeiro evento endotérmico em 193,49 ºC. As analises de DSC revelaram que a amostra pura sofre fusão em 206,49 ºC e a amostra dopada em 196,02 ºC e que não há nenhum evento térmico que caracterize uma transição de fase antes da fusão. O estudo de espalhamento Raman com altas temperaturas foi realizado em três regiões espectrais com elevação gradual da temperatura (40°C a 170°C). A primeira em 40 cm-1 a 300 cm-1 , correspondente aos modos de vibração externa a segunda em 500 cm-1 e 1500 cm-1 e a terceira em 2800 cm-1 e 3100 cm-1 que estão relacionadas aos modos de vibração interna. As medidas mostraram que houve um enfraquecimento nas ligações intermoleculares do cristal de β – alanina dopada com íons Ag+ e que toda a dinâmica do estudo esta sendo descrita pelas duas bandas de menor energia dos modos de rede. Assim, os cristais possuem boa transparência e com estudos óticos podem ser aplicados na optica não linear.
85

Estudo de altas pressões por espectroscopia Raman no cristal de Nitrato de L-Alanina / Study of high pressures by Raman spectroscopy on L-Alanine Nitrate crystal

Soares, Rilleands Alves 18 April 2017 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-05-09T19:00:17Z No. of bitstreams: 1 RilleandsSoares.pdf: 3170256 bytes, checksum: 735ff5b185572666283ce8413340aa71 (MD5) / Made available in DSpace on 2017-05-09T19:00:17Z (GMT). No. of bitstreams: 1 RilleandsSoares.pdf: 3170256 bytes, checksum: 735ff5b185572666283ce8413340aa71 (MD5) Previous issue date: 2017-04-18 / In this work nitrate L-Alanine crystals (LAN) were prepared by slow evaporation technique at room temperature and characterization by X-ray diffraction and Raman scattering at room temperature and high pressures in the amino acid salt crystals LAN. The crystals grew after six months of rest. The growth solution was acidic with pH 1.0. With the XRD pattern of the material and the Rietveld analysis, it was found that at room temperature LAN crystallizes in orthorhombic space group (P212121) with four molecules per unit cell. The refinement of the quality parameters were satisfactory, with Rp = 5.52%, 7.73% and S = 1.4. The results of Raman scattering with hydrostatic pressure variation between 0 GPa and 7.4 GPa, show that the LAN crystal undergoes a phase transition between 3.5 and 4.1 GPa, as suggested by the changes in the vibrational modes, both In the low wave number as in the internal mode regions. The correlation between the configuration of hydrogen bonding at ambient pressure and the occurrence of phase transition with pressure variation was proposed. After decompression at ambient pressure, the original spectra were recovered indicating that the phase transitions are reversible. / Este trabalho descreve o preparo dos cristais de nitrato de L-Alanina (NLA) pela técnica de evaporação lenta do solvente à temperatura ambiente e realizadas medidas de caracterização por difração de raios X e espalhamento Raman à temperatura ambiente e a altas pressões em cristais do sal de aminoácido de NLA. Os cristais cresceram após seis meses de repouso. A solução de crescimento era ácida com pH 1,0. Com o difratograma do material e a análise pelo método Rietveld, constatou-se que à temperatura ambiente o NLA cristaliza-se numa estrutura ortorrômbica (P212121) com quatro moléculas por célula unitária. Os parâmetros de qualidade do refinamento foram satisfatórios, com Rp = 5,52 %, Rwp = 7,73 % e S = 1,4. Os resultados de espalhamento Raman com variação da pressão hidrostática entre 0 GPa e 7,4 GPa, sugerem que o cristal de NLA, sofre uma transição de fase entre 3,5 e 4,1 GPa, evidenciando pelas mudanças nos modos vibracionais, tanto no número de onda baixo como nas regiões de modos internos. Foi proposta a correlação entre as ligações de hidrogênio à pressão ambiente e a ocorrência de transição de fase com variação de pressão. Após a descompressão à pressão ambiente, os espectros originais foram recuperados indicando que as transições de fase são reversíveis.
86

Síntese e caracterização do cristal de B-Alaninato de Níquel (II) / Synthesis and Characterization of the Crystal of Nickel (II) B-Alaninate

CRUZ, Nayara da Silva 14 July 2017 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-09-21T17:25:16Z No. of bitstreams: 1 NayaraCruz.pdf: 2821867 bytes, checksum: 4cc762016119d71d331457a53080cac3 (MD5) / Made available in DSpace on 2017-09-21T17:25:16Z (GMT). No. of bitstreams: 1 NayaraCruz.pdf: 2821867 bytes, checksum: 4cc762016119d71d331457a53080cac3 (MD5) Previous issue date: 2017-07-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The crystals based in Amino acid have been studied recently, mainly due to their useful properties for electronic, non-linear optical and magnetic applications. One of most used amino acids are β-alanine, whose complexes with nickel were studied in the 1990s. However, there are no studies on the thermal and structural stability of this material. In order to better investigate β-alanine complexes with metal ions, this work presents the structural and thermal study of nickel (II) β-alaninate crystal. The crystals were grown by slow evaporation of the solvent. The crystals grew after a period of 30 days. The techniques used for the characterization of the sample were: X-Ray Diffraction (XRD) along with the refinement by the Rietveld method, Raman spectroscopy at room temperature and with temperature variation, Fourier Transform Infrared Spectroscopy (FTIR) and Thermal Analysis By Differential Exploratory Calorimetry (DSC). The XRD data showed that the crystals grown were the desired ones, presenting the same triclinic structure and spatial group P1. The DSC results showed events corresponding to water loss followed by phase transformation and subsequent melting at approximately 138 ° C. The results obtained by Raman Spectroscopy at room temperature and with temperature variation showed 32 spectral bands for the crystal, of which 5 are referring to the network modes or external modes. Raman spectroscopy confirmed the observed phase transformation on the DSC curve due to the loss of the water molecule. As the temperature increases, the bands shift to the number of smaller waves. For the results obtained at temperatures above 137 ° C the appearance of spectral bands was not observed, indicating that the crystal was melted as observed in the DSC curve. The results of X-ray diffraction as a function of temperature showed that, as the temperature increases, the peaks shift to smaller angles and that the process is non-reversible, characteristic of a phase transformation. For the FITR data we have that most bands have a high spectral absorption showing a total of 26 bands. The present result shows that the crystal is thermally stable up to 110 ° C and can be used for application below this temperature. / Cristais à base de aminoácidos têm sido estudados recentemente, principalmente devido à suas propriedades úteis para aplicações eletrônicas, óptica não linear e magnéticas. Dentre os aminoácidos mais utilizados há a β-alanina, cujos complexos com níquel foram estudados na década de noventa. Contudo, não há estudos da estabilidade térmica e estrutural desse material. No intuito de investigar melhor complexos de β-alanina com íons metálicos, este trabalho apresenta o estudo estrutural e térmico do cristal de β- alaninato de níquel (II). Os cristais foram crescidos por meio do método de evaporação lenta do solvente. Os cristais cresceram após um período de 30 dias. As técnicas utilizadas para a caracterização da amostra foram: Difração de Raios X (DRX) juntamente com o refinamento pelo método de Rietveld, Espectroscopia Raman em temperatura ambiente e com variação de temperatura, Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) e Análise Térmica pela técnica de Calorimetria Exploratória Diferencial (DSC). Os dados de DRX comprovaram que os cristais crescidos eram os desejados, apresentando a mesma estrutura triclínica e grupo espacial P1. Os resultados de DSC mostraram eventos que correspondem à perda de água seguida da transformação de fase e posterior fusão em aproximadamente 138°C. Os resultados obtidos por Espectroscopia Raman à temperatura ambiente e com variação de temperatura apresentaram 32 bandas espectrais para o cristal, das quais cinco são referentes aos modos de rede ou modos externos. A espectroscopia Raman confirmou a transformação de fase observada na curva de DSC, devido à perda da molécula de agua. À medida que a temperatura aumenta, ocorreu o deslocamento das bandas para número de ondas menores. Para os resultados obtidos em temperaturas superiores a 137°C não se observou o aparecimento de bandas espectrais, indicando que o cristal sofreu fusão conforme observado na curva de DSC. Os resultados de Difração de Raios X em função da temperatura mostraram que, à medida que ocorre o aumento da temperatura ocorre o deslocamento dos picos para ângulos menores e que o processo é não reversível, característica de uma transformação de fase. Para os dados de FITR, a maioria das bandas apresentam uma alta absorção espectral mostrando um total de 26 bandas. O presente resultado mostra que o cristal é termicamente estável até 110°C podendo ser utilizado para aplicação abaixo dessa temperatura.
87

Estudo do metaboloma salivar e sua associação com a doença periodontal em pacientes com síndrome de Down / Saliva metabolome in patients with Down syndrome and its association with periodontal disease

Rafael Celestino de Souza 03 February 2016 (has links)
Os pacientes com Síndrome de Down (SD) possuem grande incidência de doença periodontal (DP), caracterizada por um curso precoce e com maior severidade. O estudo de metaboloma pode contribuir para o entendimento deste curso da doença, identificando possíveis metabólitos como biomarcadores nestes indivíduos. Para entender o perfil metabolômico dos indivíduos com síndrome de Down e a sua relação com a doença periodontal, realizamos a identificação de metabólitos salivares de adolescentes e adultos jovens, entre 12 e 21 anos, ambos os gêneros. Foram coletados dados sobre o estado geral de saúde e realizados exames clínicos bucais, como índice de higiene oral simplificado, sangramento e profundidade de sondagem. Para a análise do metaboloma foi coletada amostra de saliva não estimulada, analisadas por meio de cromatografia gasosa acoplada á espectrometria de massas. Saliva e fluido crevicular gengival também foram coletados para identificação microbiana através do MALDI-TOF. Os dados encontrados foram submetidos a análise estátisca por meio da Análise dos Componentes Principais (PCA) e quantificação relativa dos metabólitos foi avaliada por testes não paramétricos, Mann-Whitney e Kruskal-Wallis. Foi possível observar através dos modelos de PCA separação dos indivíduos com SD e controles, independente da doença periodontal. A quantificação relativa revelou maiores níveis de glicina, lprolina, l-leucina, l-serina, ácido palmítico, ácido pentanóico, ácido tetradecanóico, tirosina e l-fenilalanina nos grupos SD quando comparados aos controles. Controles com DP também apresentaram níveis elevados de glicina, l-alanina, l-serina e manopiranose quando comparados com controles saudáveis. A microbiota de indivíduos com SD apresentous diferenças siginificantes em relação aos individuos controles, principalmente para Rothia dentocariosa, Staphylococcus epidermidis, Tannerella forsythia quando avaliado a saliva e A. Actinomycetemcomitans, Micrococcus luteus, Rothia aeria, Treponema denticola no fluido crevicular gengival. Em conclusão, o perfil metabolômico impresso nos indivíduos com SD difere significativamente dos indivíduos controles, independente da doença periodontal. Entretanto, os metabólitos que diferenciam indivíduos controles com e sem DP, apresentam-se elevados em todos indivíduos com SD, promovendo novos \"insights\" para o perfil metabólico relacionado a DP na SD. / Down Syndrome (DS) patients have a high incidence of periodontal disease (PD), characterized by an early course and greater severity. The metabolome study may contribute to the understanding of the disease course, identifying possible metabolites as biomarkers in these individuals. To understand the metabolomic profile of the DS and their relationship with PD, we conducted the identification of salivary metabolites of adolescents and young adults between 12 and 21 years, both genders. Data were collected on general health and was performed oral clinical examination, as the IHOS, bleeding index and probing depth. For metabolome analysis was collected unstimulated saliva sample, analyzed by gas chromatography coupled to mass spectrometry. Saliva and gingival crevicular fluid were also collected for microbial identification by MALDI-TOF. Data were submitted to analysis-statistic by PCA and relative quantification of metabolites was evaluated by Mann-Whitney and Kruskal-Wallis tests. It can be observed through the PCA models separation of DS groups and controls groups, regardless of periodontal disease. Relative quantification showed higher levels of glycine, L-proline, L-leucine, L-serine, palmitic acid, pentanoic acid, tetradecanoic acid, tyrosine and L-phenylalanine in the SD groups when compared to controls groups. Controls with PD also showed high levels of glycine, L-alanine, L-serine and mannopyranose compared with healthy controls. The microbiota of individuals with DS groups show significant differences compared to control groups, especially for Rothia dentocariosa, Staphylococcus epidermidis, Tannerella forsythia when evaluated saliva and A. actinomycetemcomitans, Micrococcus luteus, Rothia aeria, Treponema denticola in gingival crevicular fluid. In conclusion, the printed metabolomic profile in individuals with Down syndrome differs significantly from control subjects, regardless of periodontal disease. However, the metabolites that distinguish controls group with and without PD, show up high in all DS individuals, promoting new \"insights\" to the metabolic profile related to PD in DS.
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Effekt av ß-alanintillskott på Muskelkarnosin, Blodlaktat och Fysisk prestation. : En Litteraturstudie med Meta-analys / Effect of ß-alaninesupplement on Musclecarnosine, Bloodlactate and Physical performance : A Literature Study with Meta-Analysis

Fredriksson, Benjamin January 2019 (has links)
Bakgrund: Användningen av kosttillskott har ökat de senaste åren. Detta leder till att det kontinuerligt produceras nya tillskott som inte har någon evidens för effekt. Ett kosttillskott som har fått ökat intresse de senaste åren är ß-alanin. För aktiviteter där glykolys stimuleras och mjölksyraproduktionen är hög har ß-alanin föreslagits vara ett effektivt tillskott. ß-alanins effekter och funktioner i kroppen är inte helt fastställda. Syfte: Syftet med denna studie var att analysera ß-alanintillskotts effekter på muskelkarnosinkoncentrationen, blodlaktat, muskelstyrka och uthållighet/tid till utmattning.  Metod: Studien är utformad som en systematisk litteraturstudie med meta-analys. Pubmed användes som databas för litteratursökningen. Meta-analyser utfördes för karnosinkoncentration och blodlaktat.  Resultat: Dosering med 3.2g/dag av ß-alanin under 4 veckor visar signifikanta effekter på karnosinkoncentrationen. Effektstorleken på karnosinkoncetration mellan grupperna var 1.255 (p = 0.001) efter 4 veckor av supplementering. Effektstorleken mellan grupperna för 10 veckor var 2.054 (p=0.008). Inga signifikanta effekter på blodlaktat, effektstorleken mellan grupperna var 0.148 (p=0.278). Signifikant effekt av ß-alanin på tid till utmattning (TTE) vid hög-intensitets cykling. ß-alanintillskott visade signifikant effekt på en repetition max (1RM) och helkroppsstyrka (WBS). Slutsats: ß-alanintillskott med en dosering på minst 3.2g/dag i 4 veckor ger en signifikant ökning av muskelkarnosinkoncentrationen. Större dosering än 3.2g visar inte på större effekt. ß-alanin har inte någon signifikant effekt på blodlaktat. Signifikant effekt visades på TTE för hög-intensitetscykling/sprinter. ß-alanintillskotts effekt på muskelstyrka är svår identifierad eftersom det bara var två studier som kunde inkluderas. / Background: The use of dietary supplements has increased in recent years. Which leads to the continuous production of new supplements that have no evidence of effect. A dietary supplement that has gained increased interest in recent years is β-alanine. For activities where glycolysis is stimulated and lactic acid production is high, β-alanine has been suggested to be an effective supplement. The effects and functions of ß-alanine in the body are not fully established. Purpose: The purpose of this study was to analyze the effects of ß-alanine supplementation on muscle carnosine concentration, blood lactate, muscle strength and endurance/time to exhaustion. Method: The study is designed as a systematic literature study with meta-analysis. Pubmed was used as a database for the literature search. Meta-assays were performed for carnosine concentration and blood lactate. Result: Dosage at 3.2g / day of β-alanine for 4 weeks shows significant effects on carnosine concentration. The size of the effect on carnosine concentration between the groups after 4 weeks of supplementation was 1,255 (p = 0.001). The effect size between the groups for 8-10 weeks was 2,054 (p = 0.008). No significant effects on blood lactate, the effect size between the groups was 0.148 (p = 0.278). Significant effect of βalanine on time to fatigue (TTE) in high intensity cycling. β-alanine supplementation showed significant effects on a repetition max (1RM) and whole body strength (WBS). 2 Conclusion: β-alanine supplementation with a dosage of at least 3.2g / day for 4 weeks gives a significant increase in muscle carnosine concentration. Larger dosages than 3.2g does not show greater effect. β-alanine does not have a significant effect on blood lactate. Significant effect was shown on TTE for high intensity cycling sprints. The ßalanine supplemental effect on muscle strength is difficult to identify because only two studies could be included.
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Exploiting enzyme promiscuity for rational design

Branneby, Cecilia January 2005 (has links)
Enzymes are today well recognized in various industrial applications, being an important component in detergents, and catalysts in the production of agrochemicals, foods, pharmaceuticals, and fine chemicals. Their large use is mainly due to their high selectivity and environmental advantage, compared to traditional catalysts. Tools and techniques in molecular biology offer the possibility to screen the natural sources and engineer new enzyme activities which further increases their usefulness as catalysts, in a broader area. Although enzymes show high substrate and reaction selectivity many enzymes are today known to catalyze other reactions than their natural ones. This is called enzyme promiscuity. It has been suggested that enzyme promiscuity is Nature’s way to create diversity. Small changes in the protein sequence can give the enzyme new reaction specificity. In this thesis I will present how rational design, based on molecular modeling, can be used to explore enzyme promiscuity and to change the enzyme reaction specificity. The first part of this work describes how Candida antarctica lipase B (CALB), by a single point mutation, was mutated to give increased activity for aldol additions, Michael additions and epoxidations. The activities of these reactions were predicted by quantum chemical calculations, which suggested that a single-point mutant of CALB would catalyze these reactions. Hence, the active site of CALB, which consists of a catalytic triad (Ser, His, Asp) and an oxyanion hole, was targeted by site-directed mutagenesis and the nucleophilic serine was mutated for either glycine or alanine. Enzymes were expressed in Pichia pastoris and analyzed for activity of the different reactions. In the case of the aldol additions the best mutant showed a four-fold initial rate over the wild type enzyme, for hexanal. Also Michael additions and epoxidations were successfully catalyzed by this mutant. In the last part of this thesis, rational design of alanine racemase from Geobacillus stearothermophilus was performed in order to alter the enzyme specificity. Active protein was expressed in Escherichia coli and analyzed. The explored reaction was the conversion of alanine to pyruvate and 2-butanone to 2-butylamine. One of the mutants showed increased activity for transamination, compared to the wild type. / QC 20100929
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Alanina aminotransferasa en Sparus aurata: control de la expresión génica mediante RNAi y de la actividad enzimática por aminooxiacetato

González García, Juan Diego 31 October 2012 (has links)
Los peces carnívoros presentan baja capacidad para utilizar carbohidratos provenientes de la dieta y controlar los niveles de glucosa en sangre. En comparación con los mamíferos, estos animales tras la ingesta de glucosa o de dietas con alto contenido en carbohidratos, muestran una hiperglucemia mas prolongada. La alanina aminotransferasa (ALT) constituye un nexo de interacción entre el metabolismo de aminoácidos y el de carbohidratos al catalizar la reacción de la transaminación reversible entre L-alanina y 2-oxoglutarato para formar piruvato y L-glutamato. Estudios previos de nuestro grupo indicaron la presencia de tres isoformas ALT en dorada (Sparus aurata): las isoenzimas citosólicas cALT1 y cALT2 y una isoforma mitocondrial, mALT. En hígado de dorada, la expresión de cALT2 incrementa en situación de gluconeogénesis mientras que cALT1 predomina durante el período postprandial para la utilización de los nutrientes de la dieta. El objetivo general del presente estudio es comprender a nivel molecular los efectos metabólicos derivados de la inhibición de ALT en peces para ayudar a establecer nuevas aplicaciones biotecnológicas orientadas a mejorar la utilización de los nutrientes de la dieta. Así, en acuicultura, identificar los efectos metabólicos asociados a la modulación de la actividad ALT constituye un punto de interés para conocer si es posible efectuar una sustitución parcial de las proteínas de la dieta por carbohidratos u otros nutrientes, a fin de reducir el coste de la producción en acuicultura y disminuir la eutrofización de las aguas del entorno. Nuestros estudios muestran que la inyección intraperitoneal de doradas con nanopartículas del complejo pCpG-siRNA-quitosán resultó adecuada para promover la expresión de un siRNA para bloquear la expresión de cALT1 en hígado de Sparus aurata. La inyección intraperitoneal de nanopartículas de pCpGsi1sh1-quitosán promovió la silenciación de cALT1 a nivel de mRNA y actividad enzimática en hígado de dorada. Por otra parte, hemos analizado la inhibición postranscripcional de la actividad ALT in vivo e in vitro con el compuesto aminooxiacetato (AOA) y analizado los cambios promovidos en metabolitos y enzimas clave en el metabolismo intermediario de carbohidratos y proteínas en hígado de Sparus aurata, tras la ingesta del AOA con dietas de diferente composición. In vitro, el AOA ejerce una inhibición dependiente de dosis sobre la actividad ALT hepática citosólica y mitocondrial. In vivo, el AOA se comportó como inhibidor de la actividad ALT citosólica hepática, pero no de la mitocondrial. Una exposición a largo plazo a AOA promovió un aumento de la actividad piruvato quinasa en el hígado de dorada, independientemente de la composición de la dieta suministrada a los peces. Los estudios de 1H-RMN mostraron que la inclusión de AOA en la dieta promueve una disminución en los niveles hepáticos de alanina, glutamato y glucógeno. Adicionalmente, los análisis de 2H-RMN indicaron una tasa de renovación más alta de alanina en el hígado de los peces alimentados con una dieta con un contenido alto en carbohidratos y bajo en proteínas y que el AOA disminuye el enriquecimiento de alanina en 2H independientemente de la composición de la dieta. Los estudios derivados de esta tesis indican que la inhibición dependiente de AOA de la actividad de la ALT citosólica podría contribuir a aumentar el uso de nutrientes por carbohidratos de la dieta de Sparus aurata. / Carnivorous fish have low ability to utilize dietary carbohydrates and controlling blood glucose levels. Compared with mammals, these animals after ingestion of glucose or diets high in carbohydrates show a more prolonged hyperglycemia. Alanine aminotransferase (ALT) links carbohydrate and amino acid metabolism through catalysing the reversible transamination between L-alanine and 2-oxoglutarate to form pyruvate and L-glutamate. Previous studies from our group indicated the presence of three isoforms ALT bream (Sparus aurata): cALT1 cytosolic isoenzymes and cALT2 and a mitochondrial isoform, mALT. In the liver os Sparus aurata cALT2 expression increases gluconeogenesis situation prevails while cALT1 during the postprandial period for the utilization of dietary nutrients. The overall objective of this study is to understand at a molecular level the resulting metabolic effects from the inhibition of ALT in fish to help establish new biotechnological applications aimed to improve the use of dietary nutrients. Thus in aquaculture, identifying metabolic effects associated with ALT activity modulation is a point of interest to know if it is possible to perform a partial replacement of dietary proteins by carbohydrate or other nutrients, to reduce the cost of Aquaculture production and reduce eutrophication of the environment. Our studies show that intraperitoneal injection of a chitosan-pCpG-siRNA nanoparticles complex to Gilthead seabream proved to be suitable for the expression of a siRNA to silence the expression of liver cALT1 in Sparus aurata. Intraperitoneal injection of pCpGsi1sh1-chitosan nanoparticles complex promoted cALT1 silencing at the mRNA level and a decrease of liver enzyme activity of Gilthead seabream. In the present study amino-oxyacetate (AOA) was used to evaluate its effect on liver ALT activity of the carnivorous fish Sparus aurata. Moreover, the derived metabolic effects on metabolites and other key enzymes of glycolysis, gluconeogenesis and the pentose phosphate pathway were also studied. A dose-effect-dependent inhibition of AOA on hepatic cytosolic and mitochondrial ALT activity was observed in vitro. In vivo, AOA behaved as an inhibitor of hepatic cytosolic ALT activity. A long-term exposure to AOA increased pyruvate kinase activity in the liver irrespective of the composition of the diet supplied to fish. 1H NMR studies showed that inclusion of AOA to the diet decreased the hepatic levels of alanine, glutamate and glycogen. Moreover, 2H NMR analysis indicated a higher renewal rate for alanine in the liver of fish fed with a high-carbohydrate/low-protein diet, while AOA decreased alanine 2H-enrichment irrespective of the diet. The present study indicates that AOA-dependent inhibition of the cytosolic ALT activity could help to increase the use of dietary carbohydrate nutrients by the Sparus aurata fish.

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