FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Um dos principais objetivos do tratamento endodÃntico dos canais radiculares de dentes com polpa necrÃtica consiste em eliminar os microorganismos localizados no sistema de canais radiculares. Dessa forma, esta dissertaÃÃo, constituÃda por um artigo, propÃe-se a avaliar o efeito antibacteriano do preparo quÃmico-mecÃnico e de uma pasta à base de hidrÃxido de cÃlcio sobre bactÃrias presentes em canais radiculares de dentes decÃduos necrosados apÃs trauma bem como verificar a presenÃa dos microorganismos Fusobacterium nucleatum e bacilo pigmentado negro nestes dentes. Seguindo os critÃrios de inclusÃo, a amostra consistiu de 18 dentes, totalizando 14 pacientes. As coletas microbiolÃgicas foram realizadas apÃs a abertura coronÃria (C1) e 72h apÃs a remoÃÃo da medicaÃÃo intracanal (C3), sendo que, para 10 dentes, realizou-se outra coleta apÃs a instrumentaÃÃo (C2). As coletas foram realizadas introduzindo-se sequencialmente 3 cones de papel absorvente estÃril, de diÃmetro visualmente compatÃvel com o do canal radicular, no interior deste por aproximadamente 1 minuto. ApÃs este intervalo, os cones foram removidos, transferidos para um tubo contendo um fluido reduzido para transporte e levados ao laboratÃrio para processamento microbiolÃgico. Na C1, os microorganismos foram isolados em 17/18 (94,4%) dos canais radiculares, sendo a mÃdia de CFUs de 5.4 x 105, na C2, em apenas 1/10 (10%) canal radicular, com uma mÃdia de 4.3 x 102, e na C3 em 15/18 (83.3%), com mÃdia de 1.5 x 105. Houve uma diferenÃa estatisticamente significante entre C1 e C2, o mesmo nÃo ocorrendo entre C1 e C3 e entre C2 e C3. O microorganismo Fusobacterium nucleatum e o bacilo pigmentado negro foram observados em 55.5% (10/18) e 11.1% (2/18), respectivamente, na C1, nÃo sendo detectados na C2, e na C3 estavam presentes em 16.6% (3/18) e 5.5% (1/18), respectivamente. Na C1, observou-se uma predominÃncia de cocos gram-negativos (15/18) e bacilos gram-negativos (14/18), representando 83.3% e 77.8%, respectivamente. Na C2, os Ãnicos morfotipos detectados foram cocos gram-positivos (1/10), presente em 10% das amostras positivas, e na C3, os cocos-gram positivos predominaram (66.7%). Pode-se concluir que o preparo quÃmico-mecÃnico desempenhou sua funÃÃo antibacteriana ao reduzir significativamente o nÃmero de microorganismos do canal principal, porÃm o hidrÃxido de cÃlcio possui um efeito antibacteriano limitado, nÃo sendo capaz de prevenir o recrescimento de bactÃrias apÃs seu uso como medicaÃÃo intracanal. / One of the main objectives of endodontic treatment of roots canals with necrotic pulps consists in eliminating the microorganisms spread throughout the ramifications of root canal system. This study, comprised by one manuscript, had the objective to evaluate the antiseptic efficacy of biomechanical preparation and a calcium hydroxide-paste in root canals of human primary teeth with necrotic pulp after trauma and to detect the microorganisms Fusobacterium nucleatum and black-pigmented bacilli in this teeth. According to stringent inclusion criteria, 18 primary teeth with necrotic pulp were selected. Bacterial samples were taken after crown access (S1) and 72h after the removal of dressing with a calcium hydroxide paste (S3), but to 10 teeth were taken a other bacterial sample after chemomechanical preparation with 0.5% NaOCl as an irrigant (S2). Bacteriological samples were collected by introducing 3 sequential sterile absorbent paper points, of a size visually compatible with the root canal diameter. After approximately 1 min, the paper points were removed and placed in a test tube containing reduced transport fluid and were sent for microbiological evaluation. In the S1, the microorganisms were found in 7/18 (94,4%) of the samples, with a colony forming units (CFUâs) media of 5.4 x 105. In the S2, bacteria were cultured in only 1/10 (10%) root canal, with the CFUâs media of 4.3 x 102, and in the S3 bacteria were cultured in 15/18 (83.3%), with the CFUâs media of 1.5 x 105. A statistically significant reduction in bacterial counts was observed between S1 and S2, however no statistically significant difference was observed for comparisons involving S1 and S3, and S2 and S3. The microorganisms Fusobacterium nucleatum and black-pigmented bacilli were detected in 55.5% (10/18) and 11.1% (2/18), respectively, in the S1, no were found in the S2, and in the S3 were found in 16.6% (3/18) and 5.5% (1/18), respectively. In the S1, the gram-negative cocci (15/18) and gram-negative rods (14/18) were the most prevalent groups (83.3% and 77.8%, respectively). In the S2, the gram-positive cocci was the only group of the bacteria observed (1/10), and in the S3, the gram-positive cocci was the group most commonly recovered (66.7%). It was conclude that biomechanical preparation were important in the antisepsis of the root canal because reduced significantly the number of bacteria in the main canal however the calcium hydroxide paste had a antibacterial efficacy limited, no prevent the regrowing bacterial after used as dressing intracanal.

As proteínas são importantes componentes da matriz extracelular da polpa dentária e possuem diferentes funções nos tecidos. A literatura odontológica não relata como os proteoglicanos se distribuem e agem na matriz extracelular de dentes decíduos durante o processo fisiológico de rizólise. Foi objetivo do trabalho analisar as expressões dos proteoglicanos biglican e decorin e relacioná-las com as diversas fases do processo de rizólise. Para isso foram utilizados dentes decíduos humanos extraídos e livres de lesões de cárie, apresentando vários estágios de reabsorção radicular, divididos em três grupos: com dois terços ou mais do comprimento radicular médio, um terço ou mais do comprimento radicular médio e menos de um terço do comprimento radicular médio. Foi utilizada a técnica da imunoistoquímica, com o método da estreptavidina-biotina-peroxidase, e anticorpos contra as proteínas anteriormente citadas. Os resultados mostraram que os proteoglicanos estudados apresentaram imunorreatividade na matriz extracelular da polpa e da dentina dos dentes nas três fases de reabsorção. Foi possível concluir que houve diferença na distribuição e no padrão de expressão dos proteoglicanos biglican e decorin apenas na área de reabsorção, nos dentes decíduos hígidos nas três fases de rizólise o que sugere um papel regulador destes proteoglicanos no processo de reabsorção fisiológica nos dentes decíduos hígidos. / Proteins are important components in pulp extracellular matrix and perform several different roles in the body tissues. The distribution and functions of some proteins have already been described but there aren?t studies showing how the proteoglycans are distributed and act in the extracellular matrix of deciduous teeth at the physiological resorption process. The aim of the present work was to study the expression and distribution of the following non-collagenous components of the extracellular matrix: biglycan and decorin in deciduous teeth dental tissues at the physiological root resorption. Hygid human deciduous teeth that were extracted for orthodontic reasons were grouped together according to root length: group I - two thirds or more of average length root, group II - one third or more of average length root and group III ? less than one third of average length root. The streptavidin-biotinperoxidase method of immunohistochemistry was used with antibodies against the antigens previously quoted. The results showed that the proteoglycans had been found in pulp and dentin extracellular matrix in all groups. In conclusion, biglycan and decorin were differentially found only in the resorption area, between tissues in resorption process and its adjacent zone, which make us believe that these proteoglycans act regulating the physiological resorption process in hygid deciduous teeth.

The effects of controlled atmosphere on the metabolism of Golden Delicious and Rome Beauty apples, Anjou pears, and Lambert and Bing cherries were studied with respect to changes caused in the normal metabolic functions carried on during storage of these fruits. Atmospheres consisting of 1.5 per cent CO2 and 2.5 per cent O2 for the apples and pears and 10.5 per cent CO2 and 2.5 per cent O2 for the cherries were employed. Fungi of the strains Botrytis alli, Rhizopus nigricans, and Penicillium expansum were subjected to controlled atmospheres at 21° C to determine the toxic effect of CA. The fungi were grown on agar plates instead of fruit to prevent bias, such as condition of the fruit. Periodically, fruit was taken directly from the storage treatments and analyzed for CO2 evolution, for total and reducing sugars, organic acids, amino acids, and cytochrome c oxidase. Fruits were also taken from the storage treatments and held for a specific time at 15° C before analysis. The CA used in this experiment had an inhibitory effect on the fungi that were used. Botrytis alli and Penicillium expansum were particularly susceptible. It was found the height of the mycelial mat was less, the mycelium growth was less, and while sporulation was not eliminated, it was severely retarded. Combinations of CA and lowered temperatures should attain a high degree of fungal control. The results showed that CA had an inhibitory effect on the metabolic system of stored fruits. The specific areas of metabolic inhibition are not known exactly. This inhibition does not appear to be of a permanent nature as shown by the post storage analysis. Any differences that occurred in the CA stored fruit as contrasted to the fruit from the conventional stored fruit appeared to be able to correct themselves once they were removed from the CA.

published_or_final_version / abstract / toc / Dentistry / Master / Master of Philosophy

Mercury (Hg) research in Ontario has centered on aquatic environments since fish can be a significant source of methylmercury for humans. Interactions between terrestrial and aquatic environments in regards to the Hg cycle have received less attention. This study focuses on the role of trees as a source and/or sink of Hg to the environment and the ap- plicability of deciduous trees as biomonitors for Hg. Leaf, bark and wood core samples were taken from a variety of deciduous species including Acer spp. (sugar, silver and red maple), Quercus spp. (red oak), Populus spp. (eastern cottonwood), and Salix spp. (willow) mainly from the Dorset and Kingston, ON regions. Examination of seasonal variation of Hg concentrations ([Hg]) in leaves indicated that average autumn leaf Hg ranged from 17– 45 ng/g and differed significantly among species. Leaf [Hg] increased with the growing season and roughly corresponded to regional atmospheric [Hg]. Microspatial trends in leaf [Hg], such as position on a branch, may increase variability. Tree cores from contami- nated and reference sites in the Kingston area showed that although dendrochronological techniques are not appropriate for estimating historical atmospheric Hg, they are useful for estimating the total Hg burden of a single tree. Populus and Salix, had the greatest bark and wood [Hg] with maximums reaching 18 ng/g. This was significantly higher than more inland trees such as Quercus and Acer, with maximum values of 7 and 1.2 ng/g for bark and wood [Hg]. Individual, average sized trees in this study contained a total of 0.4–2.6 mg of Hg. This study will provide forest and watershed managers with a better understanding of the importance of trees in the Hg cycle and the contribution of leaf and wood Hg to litterfall and waterbodies in southern Ontario. / Thesis (Master, Biology) -- Queen's University, 2007-12-18 23:48:21.97

No description available.

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Thesis (doctoral)--University of Göteborg, 1983. / Extra t.p. with thesis statement inserted. Includes the author's seven published papers. Includes bibliographical references.

Thesis (doctoral)--University of Göteborg, 1983. / Extra t.p. with thesis statement inserted. Includes the author's seven published papers. Includes bibliographical references.

Thesis (M.D.Sc.) - University of Queensland, 2005. / Includes bibliographical references.