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Full-Text Articles in Organisms

Disinfection Of Dentin By Intracanal Laser Irradiation: An In Vitro Model, Silvia Cristina Mafra Cecchini Dec 2000

Disinfection Of Dentin By Intracanal Laser Irradiation: An In Vitro Model, Silvia Cristina Mafra Cecchini

Loma Linda University Electronic Theses, Dissertations & Projects

A possible cause for root canal failure is the persistence of bacteria that have colonized dentinal tubules. To reduce this risk and, if possible, to also shorten the time consuming endodontic therapy, new equipment and materials are constantly being introduced. The aim of the present investigation was to study the effect of disinfection of dentinal tubules by intracanal laser irradiation using an in vitro model. The groups irradiated by various lasers were compared with calcium hydroxide, a material frequently used as intracanal medication between appointments. Freshly extracted, intact bovine incisors were used. The root cementum was removed and the teeth …


Molecular Evolution Of Insecticidal Spore-Forming Bacteria, John Pool Apr 2000

Molecular Evolution Of Insecticidal Spore-Forming Bacteria, John Pool

Honors Theses

Molecular methods are increasingly being used to determine the phylogeny of microorganisms. This research was intended to determine phylogenetic relationships for bacteria of the species Bacillus thuringiensis and other members of the Bacillus cereus group. Each strain was analyzed by its sasp-B gene sequence to determine its species classification and relation to other strains studied. Results of this study indicated that according to the sasp-B gene tree, the species Bacillus thuringiensis is a paraphyletic with respect to both Bacillus cereus and Bacillus anthracis. Some unexpected results and implications for species designations are also discussed.


Whole Genome Sequencing Of L.Monocytogenes And L.Innocua : A Basis For Comparative Genomics Of The Genus Listeria, Rachel Purcell Jan 2000

Whole Genome Sequencing Of L.Monocytogenes And L.Innocua : A Basis For Comparative Genomics Of The Genus Listeria, Rachel Purcell

Theses

Listeria monocytogenes is a gram-positive, food-borne human and animal pathogen. L.innocua is a non-pathogenic species the most closely related to L. monocytogenes. Comparative genomics between a pathogenic and a closely related non-pathogenic species is a powerful approach for identifying genes or regions on the chromosome, which might be involved in virulence. Therefore whole genome sequencing of these two organisms was undertaken. The strategy used was based on a random approach combined with end-sequencing of a medium insert library for the finishing phase. Based on the available sequence data for these two species an in silico analysis for the presence of …