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L'étanchéité des bois des chênes sessile et pédonculé dans la direction longitudinale dépend de la quantité et de la qualité de la thyllose. Depuis quelques années, un taux de fuite anormalement élevé dans les barriques fabriquées a été noté. Une étude expérimentale a été menée sur deux tonneaux non étanches et les fuites observées ont donné lieu à une exploration fine des voies de passage du liquide coloré à l'intérieur des douelles défectueuses. Nous avons pu mettre en relation une thyllose faible ou absente avec une migration de liquide qui peut s'effectuer sur toute la longueur d'une douelle. Par ailleurs, une production spéciale de merrains a été réalisée afin de comprendre l'influence de la hauteur dans l'arbre, de l'âge cambial, de l'arrosage et des différents paramètres de maturation des merrains (temps, position dans la palette) sur la perméabilité et la thyllose. Il a été nécessaire de mettre au point une méthode pour évaluer quantitativement la thyllose. Deux méthodes sont utilisées : La première repose sur l'observation anatomique et la propriété des vaisseaux non obstrués ou partiellement obstrués par des thylles de laisser filtrer la lumière. La seconde consiste à réaliser des mesures de la perméabilité à l'air sur des éprouvettes cylindriques taillées dans la direction longitudinale. L'infradensité des échantillons a été également mesuré. Les observations en Microscopie Électronique à Balayage ont permis d'étudier la structure fine des thylles et de déceler la présence de spores et d'hyphes mycéliens. Les résultats sont analysés avec un logiciel de traitement statistique des données. Nous avons pu déterminer l'effet néfaste des développements microbiologiques, en particulier des champignons, sur la perméabilité longitudinale et la quantité de la thyllose du bois en cas de maturation trop longue / The tightness of wood sessile and pedunculate oaks in the longitudinal direction depends on the quantity and quality of tylosis. In recent years, an unusually high rate of leak in barrels made was noted. An experimental study was conducted on two barrels leaking and leakage observed resulted in a fine exploration of the pathways of the colored liquid inside the defective staves. We were able to connect a low tylosis with migration of liquid that can be done along the length of a stave. In addition, a special production of staves was conducted to understand the influence of the height in the tree, the cambial age, watering and curing parameters of staves (time, position in the stack) on the permeability and thyllose. It was necessary to develop a method to quantify the tylosis. Two methods are used: The first observation is based on anatomical and ownership of vessels not blocked or partially blocked by tylosis to let light through. The second is to take measurements of air permeability on cylindrical cut in the longitudinal direction. Infradensity of the samples were also measured. The observations in Scanning Electron Microscopy were used to examine the fine structure of tylosis and the presence of spores and mycelial hyphae. The results are analyzed with a software statistical processing of data. We were able to determine the adverse effect of microbiological growth, especially fungi, the longitudinal permeability and the amount of tylosis timber if too long maturation

Contexte : Le développement de la fonction rénale immature des nouveau-nés prématurés est soumis à des facteurs environnementaux dont l'empreinte s'étend au-delà de la période néonatale. Objectifs : 1) déterminer les valeurs de référence du débit de filtration glomérulaire (DFG) chez des grands prématurés durant le premier mois de vie, 2) déterminer l'impact des facteurs périnatals sur leur fonction rénale, 3) déterminer l'effet de l'empreinte périnatale et de la croissance staturo-pondérale sur leur fonction rénale dans l'enfance. Echantillon : Cohorte multicentrique de nouveau-nés prématurés de 27-31 semaines d'aménorrhée, avec mesure de leur fonction rénale durant la période néonatale, et à 4 ans. Résultats : 1) 275 nouveau-nés inclus. La valeur de référence médiane de DFG (mL/min/1,73m²) s'étendait de : 7,9 à J7 à 37,9 à J28. 2) Le DFG était significativement diminué à J7 chez les enfants traités par ibuprofène : 12,8±6,2 vs. 18,1±12,1 ml/min/1,73 m² ; p < 0,001. Cette baisse persistait pendant le premier mois de vie, avec une atteinte de la fonction tubulaire. Parmi les médicaments administrés aux mères ou avant J7 chez les nouveau-nés, l'ibuprofène était le seul significativement associé à un DFG inférieur à la médiane pour l'âge gestationnel à J7. 3) Une taille >= -1 DS à quatre ans était un facteur de risque d'albuminurie élevée chez 119 enfants étudiés à quatre ans. Conclusion : i) Ces valeurs de référence de DFG sont disponibles pour recherche clinique, ii) L'environnement thérapeutique néonatal est un facteur de risque d'altération de la fonction rénale et de retard à la maturation rénale, iii) La taille à quatre ans est associée au taux d'albuminurie. / Background: Physiological development of renal may be altered in preterm infants by environmental factors. Their imprinting could persist beyond the neonatal period. Objectives: 1) to determine reference values of glomerular filtration rate (GFR) during the first month of life in preterm newborns, 2) to determine the impact of perinatal factors and of the drugs often prescribed on their renal function, 3) to determine the effect of the perinatal imprinting, and of the growth and height catch-up, on their renal function in early childhood. Sample: Multicentre cohort of children born very preterm at 27-31 weeks of gestation, with a measure of their renal function during the neonatal period, and at 4 years of age. Results: 1) 275 infants included. Median reference GFR value (mL/min/1.73m²) was: 7.9 on day7 to 37.9 on day 28. 2) GFR was significantly reduced on day 7 in ibuprofen-infused infants in comparison to Controls: 12.8±6.2 vs. 18.1±12.1 ml/min/1.73 m², p < 0.001. This decrease persisted throughout the first month of life, and tubular function was also altered. Among all antenatal drugs and drugs administered during the first week of life, alone ibuprofen was significantly associated with a GFR < median reference value on day 7. 3) Height >= -1 SD in early childhood was associated with a high albuminuria in 119 four year-old preterm-born children. Conclusion: i) These GFR reference values are to be used in clinical research, ii) Neonatal therapeutic environment impairs renal function and delays its maturation, iii) The height at age four is an independent risk factor of high albuminuria in preterm-born children.

Os resultados do desempenho motor (DM) na adolescência podem ser imprecisos quando os fatores de crescimento, idade biológica e idade cronológica (IC) não são considerados. A idade óssea (IO) é reconhecida como um eficiente indicador biológico, assim, a identificação da IO em função do crescimento e o DM resultante foi o objeto de estudo em 233 escolares de 9 a 16 anos de ambos os sexos (fem=109; masc=114). A IO foi determinada por radiografia do punho e mãos e o DM medido em testes de aptidão física. A IO foi maior (0,7 anos) e mais abrangente que a IC, com maiores efeitos no sexo feminino. As moças estavam mais maduras que os rapazes em todas as idades, todavia eles apresentaram maiores médias de DM, estatura, peso corporal e menor valor de gordura. O crescimento foi mais concordante com IO enquanto o DM com IC, sem significância estatística para ambos os sexos. Concluiu-se que ao classificar adolescentes segundo o crescimento, a maturação é indispensável, porém quando o DM está envolvido, as informações de IC e sexo são suficientes. / The results of the motor performance (MP) in adolescence can be inaccurate if the growth factors, biological age and chronological age (CA) are not considered. The bony age (BA) is recognized as an efficient biological indicator, like this, the identification of BA in function of the growth and results upon MP was here the object of study in 233 from 9 to 16 years of both sexes students (femme=109; male=114). BA was determined by x-ray of the wrist and hands, and the MP was measure in physical fitness tests. BA was larger (0.7 years) and including than CA, with larger effects in the female sex. The girls were more mature than boys in all the ages, though they presented larger averages of MP, height, weight and smaller fat value. The growth was more concordant with BA while MP with CA, without statistical significance for both sexes. In conclusion, when classifying adolescents according to the growth, the maturation is indispensable, however when the MP is involved, the information of IC and sex are enough.

Os potenciais evocados auditivos de longa latência fornecem dados objetivos sobre a funcionalidade das estruturas corticais auditivas. O objetivo do presente estudo foi caracterizar a maturação do sistema auditivo central em crianças com audição normal por meio destes potenciais. Foram avaliados 56 indivíduos de ambos os sexos, com audição dentro dos padrões de normalidade, comprovada por audiometria e imitanciometria, sendo 46 crianças, de três a 12 anos, e 10 adultos jovens, os quais foram incluídos a título de comparação com a casuística infantil. O equipamento utilizado disponibilizava dois canais de registro, sendo um destinado à captação dos potenciais evocados auditivos de longa latência e outro, ao registro do artefato gerado pelo movimento ocular, visando ao seu controle. Os potenciais foram registrados com os indivíduos em estado de alerta, assistindo a um vídeo mudo, por meio de eletrodos posicionados em Cz (ativo) e A2 (referência) e os movimentos oculares, por eletrodos em posição supra e infra-orbital esquerda; o eletrodo terra foi colocado em A1. Foram analisados os valores de latência e de amplitude dos componentes P1, N1 e P2, bem como a morfologia destes componentes de acordo com a idade. Para verificar a reprodutibilidade dos potenciais registrados, foi realizado um estudo duplo-cego com a introdução da análise de uma avaliadora experiente em Eletrofisiologia, a qual não mostrou diferenças estatisticamente significantes da análise feita pela autora da pesquisa. Como resultado, constatou-se, quanto à morfologia, melhora na definição dos componentes com o avanço da idade. Foi observada diminuição nos valores de latência dos componentes P1, N1 e P2 com o avanço da idade. Não foi observada variação nos valores de amplitude com o avanço da idade para os componentes N1 e P2, exceto para o componente P1, que teve sua amplitude diminuída. Não foi observada diferença estatisticamente significante entre os sexos. Pôde-se observar que o processo maturacional do sistema auditivo central acontece de maneira gradativa, sendo as maiores modificações observadas ao se comparar crianças e adultos. / The long latency auditory evoked potentials provide objective data on the function of hearing cortical structures. This study aims at characterizing the maturation of the central hearing system, in normally hearing children, through these potentials. Fifty-six subjects from both genders, with hearing within normality patterns, verified by means of audiometry and imitanciometry, were evaluated, being 46 children in the age range 3-12, and 10 young adults, who were included for comparison with the infantile sample. The equipment utilized had two recording channels: one to catch the long latency auditory evoked potentials, and the other, to record the artifact generated by ocular movement, aiming at its control. The potentials were recorded with subjects alert, while watching a mute video, through electrodes positioned in Cz (active) and A2 (reference), and the ocular movements, through electrodes in left supra and infra-orbital position and the ground electrode was placed in A1. Values of latency and of amplitude for components P1, N1 and P2, as well as the morphology of these components, according to age, were analyzed. In order to verify the reproducibility of the recorded potentials, a double blind study was carried out, by introducing the analysis of an experienced Electrophysiology evaluator, whose analysis did not show statistically significant differences, as compared to that performed by the author of the research. Thus, as to morphology, improvement in the definition of components was seen, as age increased. A decrease in latency values of components P1, N1 and P2 was observed, as age advanced. No variation was verified in amplitude values, as age increased, for components N1 and P2, except for component P1, whose amplitude was diminished. No statistically significant difference was seen between genders. It was verified that the maturational process of the central hearing system takes place in a gradual fashion, being the greatest modifications seen, when comparing children and adults.

Multiple sclerosis (MS) is a chronic central nervous system disease featuring exacerbations of inflammation and demyelination that cause progressively debilitating clinical effects over time. Current treatments for multiple sclerosis are limited in their ability to impact overall disease progression. Research aimed at generation of novel potential therapeutics for MS is needed. Recently, kallikrein 6 (KLK6), a member of the kallikrein (KLK) family of secreted serine proteases, was found to be elevated in the cerebrospinal fluid and brain of MS patients. The fifteen known tissue-based KLKs cleave proteins through a similar mechanism, but have different binding pocket specificity, diverse localization in human tissues, and multiple biological functions. KLKs have been linked to normal human physiology (e.g. KLK4, enamel formation) and disease (e.g. KLK3, prostate cancer). KLK6 is one of the highest expressed serine proteases in the healthy human brain and is expressed predominately in mature oligodendrocytes in both human and mouse brain. The role of KLK6 in oligodendrocyte maturation, myelination, and disease is not fully understood. To evaluate the role of KLK6 in oligodendrocyte maturation, I used a pluripotent in vitro primary cell system to assess the impact of exogenous KLK6 and modulators of the KLK6 pathway on oligodendrocyte maturation. I demonstrate that signaling through KLK6 decreases the number of mature oligodendrocytes in culture, whereas blockade of KLK6 signaling increases the number of mature oligodendrocytes in culture in the presence of triiodothyronine higher than either agent alone. This work suggests that KLK6 modulation impacts oligodendrocyte maturation. To understand the potential impact of KLK6 pathway inhibition on remyelination, I used the toxin cuprizone to induce demyelination in mice. I found that animals treated with a KLK6 inhibitor had increased myelin staining in the corpus callosum compared to vehicle-treated. This work suggests that KLK6 modulates oligodendrocyte maturation and myelination and may be relevant for improving myelin-related therapeutic outcomes, particularly in multiple sclerosis. / 2019-06-12T00:00:00Z

Made available in DSpace on 2014-06-11T19:22:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-21Bitstream added on 2014-06-13T20:48:34Z : No. of bitstreams: 1 silva_lb_me_botfca.pdf: 393551 bytes, checksum: 68ad65b5247076fa26c16688a2d0cd1d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O presente trabalho teve como objetivo avaliar o efeito dos estágios de colheita e do repouso pós-colheita dos frutos na qualidade de sementes de mamoneira (Ricinus communis L.) cultivar AL Guarany 2002. Foram avaliadas 9 épocas de colheita dos racemos, dos 30 até 142 dias após a antese (DAA), em intervalos de 14 dias e quatro condições de repouso: sem e com repouso de sete dias de sementes extraídas (nuas), de frutos e de frutos presos ao racemo. Foram avaliados a massa fresca dos frutos, as dimensões e a cor de frutos e sementes; o teor de água, matéria seca, germinação e vigor das sementes (primeira contagem de germinação, porcentagem de plântulas vigorosas, emergência de plântulas em areia, índice de velocidade de emergência e condutividade elétrica). O estágio de colheita e o repouso póscolheita afetaram a qualidade das sementes de mamoneira. Sementes com máxima qualidade fisiológica e matéria seca foram obtidas de frutos colhidos aos 86 DAA. A colheita pode ser realizada até os 128 DAA sem redução da germinação, mas com prejuízos devido à queda dos frutos, dispersão das sementes aos 100 DAA e reduções do vigor. O repouso das sementes nuas permitiu a antecipação da colheita para 72 DAA sem prejuízos à germinação e matéria seca, mas com reduções de vigor. A cor dos frutos, das sementes e o teor de água das sementes foram parâmetros eficientes para a identificação do ponto de colheita, principalmente se usados conjuntamente. / This study aims to assess the effect of the harvesting stages process and the resting period of the post-harvest of fruits in the quality of castor bean seeds (Ricinus communis L.) AL Guarany 2002. It were assessed nine times in racemes, from 30 to the 142 day after anthesis (DAA), at intervals of fourteen days and four conditions of resting period; without and with resting period of seven days of seeds extracted (bare), fruits and fruits prisioners to the raceme. The fruits weight, the dimension and the fruits colour and seeds were then assessed: the content of water, dry matter, seed germination and vigour (first of germination, percentage of vigorous seedlings, emergence of seedlings in sand, speed emergence index and electric conductivity). The harvest stage and the post-harvest resting period affected the quality of castor bean seeds. Seeds with maximum physiological quality and dry matter were obtained from fruit harvested at 86 DAA. The harvest can be achieved by the 128 DAA without reducing germination, but with losses due to falling fruit, seed dispersal to 100 DAA and reductions in strength. The rest seeds bare allows the harvest to be brought forward to the 72 DAA without detriment to the germination and dry matter, but with reductions in strength. The colour of the fruits, seeds, and water content of seeds were effective parameters for the identification of the harvest point harvest, particularly if used together.

Estudos epidemiológicos e experimentos com animais têm demonstrado que a susceptibilidade à doença cárie é maior logo após o período pós-eruptivo dos dentes, decrescendo posteriormente. Na literatura, várias pesquisas ressaltam a importância do conhecimento das características do esmalte durante e após o processo de erupção, assim como dos mecanismos envolvidos na desmineralização dentária para o estabelecimento de medidas preventivas eficazes. Variações idade dependentes na susceptibilidade à doença cárie são de grande importância clínica. Entretanto, a literatura é escassa em estudos que avaliem as alterações no esmalte em dentes inclusos e após a erupção na cavidade bucal. O objetivo deste estudo in vitro foi avaliar a maturação do esmalte em profundidade, de dentes hígidos com diferentes idades eruptivas (antes da erupção na cavidade bucal; 2 a 3 anos após a erupção; 4 a 10 anos após a erupção; e com mais de 10 anos após a erupção) por meio da microdureza longitudinal. Foram utilizados 12 espécimes de esmalte de dentes hígidos de humano para cada idade eruptiva. A comparação entre a microdureza longitudinal das diferentes idades e entre as diferentes profundidades foi realizada por meio da Análise de Variância a dois critérios (ANOVA), adotando-se um nível de significância de 5%. De acordo com a metodologia adotada na presente pesquisa, foi possível concluir que houve diferença entre a microdureza longitudinal dos espécimes com diferentes idades eruptivas em todas as profundidades estudadas, evidenciando-se um comportamento crescente da mineralização quanto maior a idade eruptiva. Pôde-se observar ainda uma tendência crescente dos valores da microdureza quanto maior a profundidade do esmalte, em todos os grupos de idade. / Epidemiologic studies and caries experiments with animals have suggested that caries susceptibility of teeth decreases with age. Many researches in literature, stands out the importance of the enamel characteristics knowledge during and after the eruption process, as well as of the involved mechanisms in dental demineralization in order to establish efficient methods of prevention. Age-dependent variations in the susceptibility to caries lesions are of great clinical importance. However, literature is scarce in studies that evaluate the alterations that occur in the unerupted teeth enamel and after its eruption in the oral cavity. The aim of this study was to evaluate, in vitro, the maturation in depth of sound teeth enamel with different eruptive ages (before the eruption in the mouth, 2 to 3 years after the eruption; 4 to10 years after the eruption; and over 10 years after the eruption) through the longitudinal microhardness. We used 12 specimens of sound teeth enamel for each eruptive age. The comparison between the longitudinal microhardness of the different eruptive ages and in different depths was performed by analysis of variance with two criteria (ANOVA), adopting a significance level of 5%. According to the methodology adopted in this research, it was possible to conclude that there was a difference between the longitudinal microhardness of specimens with different eruptive ages at all depths, revealing an increase of the mineralization with age. It was observed also an increasing trend of the values of microhardness as the enamel depth increased, in all age groups studied.

Orientador: Joaquim Mansano Garcia / Coorientador: Naiara Zoccal Saraiva / Banca: César Roberto Esper / Banca: Simone Cristina Méo Niciura / Resumo: Este estudo objetivou avaliar a influência do fluido folicular (FF) e da proteína recombinante humana GDF9 adicionados ao meio de maturação sobre a qualidade de embriões bovinos produzidos in vitro. Foram realizados três experimentos utilizando o meio TCM199 como meio básico de maturação. No primeiro experimento, os oócitos foram maturados em cinco diferentes meios (0%, 25%, 50%, 75% ou 100% de FF) em quatro tempos de maturação (22, 24, 26 ou 28 h). No segundo experimento, os oócitos foram maturados nos mesmos meios utilizados no primeiro experimento e fecundados em três diferentes tempos (24, 26 ou 28 h). No terceiro experimento, foram utilizados dois meios: controle (sem FF) ou com 25% de FF e quatro níveis de suplementação (0, 25, 100 ou 200 ng/mL) com GDF9. O FF promoveu retardo da progressão meiótica, afetando a maturação nuclear e a migração de grânulos corticais para a periferia dos oócitos. O FF em altas concentrações influenciou negativamente as taxas de clivagem e de blastocisto. O GDF9, com (25%) ou sem FF, não influenciou as taxas de clivagem e de blastocisto, no entanto, interferiu positivamente sobre o percentual de embriões considerados superiores. O percentual mais elevado (82,22%) de embriões classificados como superiores foi obtido com o uso de 200 ng de GDF9 em meio de maturação acrescido de 25% de FF. Em conclusão, a adição do fluido folicular (75% e 100%) ao meio de maturação in vitro retarda a progressão meiótica, sincronizando a maturação nuclear com a citoplasmática e a suplementação do meio de maturação com proteína recombinante humana GDF9 melhora a qualidade de embriões bovinos produzidos in vitro, baseando-se na avaliação da proporção do número de células da massa celular interna (MCI) em relação ao número total de células / Abstract: This study aimed to evaluate the effects of follicular fluid (FF) and recombinant human GDF9 added to the maturation media on the quality of in vitro produced bovine embryos. Three experiments using TCM199 medium as basic maturation media were performed. In the first experiment oocytes were matured in five different media (0%, 25%, 50%, 75% or 100% of FF) during four maturation times (22, 24, 26 or 28 h). In the second experiment, the oocytes were matured in the same five media used in the first experiment and fertilized at three different times (24, 26 or 28 h). In the third experiment were used two media: control (without FF) or with 25% FF combined with four levels of supplementation (0, 25, 100 or 200ng/mL) with GDF9. The FF promoted delay of the meiotic progression, affecting nuclear maturation and cortical granules migration to the oocyte periphery. In addition FF influenced the cleavage and blastocyst rates. GDF9, without or added to FF did not affect the cleavage and blastocyst rates, however, a positive influence on the percentage of embryos considered superior was observed. The highest percentage (82.22%) of embryos considered superior was obtained with maturation media added with 25% of FF and supplemented with 200 ng of GDF9. In conclusion, addition follicular fluid (75% and 100%) to the in vitro maturation media delays meiotic progression, synchronizing nuclear to cytoplasmic maturation, and supplementation of maturation media with recombinant human GDF9 improves the quality of bovine embryos in vitro produced, based on inner cell mass cells (ICM) proportion, relative to the total cell number / Mestre