Orientadores: Cinthia Pereira Machado Tabchoury, Renata de Oliveira Mattos-Graner / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-15T04:03:05Z (GMT). No. of bitstreams: 1 Arthur_RodrigoAlex_D.pdf: 8956677 bytes, checksum: 3655b08eae9bcd1faa50719332f91c0e (MD5) Previous issue date: 2010 / Resumo: Os estreptococos do grupo mutans, em especial Streptococcus mutans, são considerados como um dos principais microrganismos relacionados à doença cárie dental. Clinicamente, esses microrganismos estão presentes na cavidade bucal na forma de diferentes genótipos, que podem apresentar diferentes características fenotípicas. Nesse sentido, foi avaliada diversidade genotípica de S. mutans em biofilme dental formado in vivo ou in situ durante 3 dias sob condições controladas de exposição à sacarose, o mais cariogênico dos carboidratos, e os seus monossacarídeos constituintes (glicose e frutose). Diferentes genótipos de S. mutans foram encontrados nessas distintas condições, entretanto, não foi observada seleção de genótipos nos biofilmes dentais formados. Além disso, as características fenotípicas de virulência desses genótipos não foram avaliadas. Sendo assim, seria importante avaliar nesses genótipos previamente isolados de biofilme dental formado in vivo e in situ, na presença ou ausência de sacarose, as características fenotípicas de cariogenicidade relacionadas à aciduricidade e à acidogenicidade, visando investigar a relação entre um alto desafio cariogênico (exposição frequente à sacarose e acúmulo de biofilme) e a virulência de S. mutans. Tanto naqueles genótipos previamente isolados de biofilme dental formado in vivo, quanto naqueles isolados de biofilme dental formado in situ, a aciduricidade foi avaliada em relação à análise da viabilidade celular em condições ácidas e em relação à atividade da bomba F-ATPase, e a acidogenicidade foi avaliada em relação à análise da curva de queda de pH devido metabolização de glicose. Além disso, oito genótipos previamente isolados do biofilme dental formado in situ durante 3 dias foram submetidos a um crescimento na forma de biofilme in vitro, condição na qual foram avaliadas a acidogenicidade, a habilidade do genótipos em sintetizar polissacarídeos extracelulares e o potencial desses genótipos para desmineralizar o esmalte dental. Em relação aos genótipos isolados de biofilme dental formado in vivo, aqueles isolados de biofilme formado na presença de sacarose foram mais ácido-tolerantes, tanto em pH 5,0 ou 2,8, e mais acidogênicos, uma vez que apresentaram menores valores de pH final durante a análise da curva de queda de pH e também maior velocidade na produção de ácidos nos primeiros 15 minutos de metabolização da glicose, que aqueles encontrados em biofilme formado na sua ausência de sacarose. Além disso, não foram encontradas diferenças expressivas na atividade da bomba F-ATPase entre essas duas condições distintas. Comportamento semelhante também foi observado para genótipos previamente isolados de biofilme dental formado in situ, com maior aciduricidade e acidogenicidade para aqueles genótipos isolados de biofilme formado na presença de sacarose. No modelo de biofilme in vitro não foram encontradas diferenças nem na acidogenicidade nem na habilidade dos genótipos de produzirem polissacarídeos extracelulares. Entretanto, os genótipos apresentaram potenciais cariogênicos distintos, não havendo relação entre o potencial cariogênico desses genótipos e a condição na qual esses genótipos foram isolados (presença ou ausência de um alto desafio cariogênico). Os resultados sugerem que as freqüentes quedas de pH decorrentes da exposição à sacarose parecem tornar os genótipos mais de S. mutans mais virulentos. Além disso, genótipos distintos de S. mutans podem apresentar diferentes potenciais cariogênicos. / Abstract: Mutans streptococci, mainly Streptococcus mutans, are considered as the main microorganisms related to dental caries. These microorganisms are present in oral cavity as distinct genotypes, which may show distinct phenotypic traits. In this context, it was evaluated the S. mutans genotypic diversity in dental biofilm formed in vivo and in situ during 3 days under controlled exposure to sucrose, the most carigenic carbohydrate, and its monosaccharides constituents (glucose and fructose). Distinct S. mutans genotypes were found under these before mentioned conditions, but no selection of them was found in dental biofilms formed. Moreover, the virulence phenotypic traits of these genotypes were not evaluated. Thus, it would be important to evaluate in these genotypes previously isolated from dental biofilm formed in vivo and in situ in the presence or absence of sucrose, the phenotypic traits of cariogenicity related to aciduricity and acidogenicity in order to investigate the relationship between a high cariogenic challenge (frequent exposure to sucrose and biofilm accumulation) and their virulence. Either in those genotypes isolated from in vivo dental biofilms, or in those isolated from in situ dental biofilms, the acidogenicity trait was evaluated through counts of viable cells in acid conditions and F-ATPase activity, and the acidogenicity trait was evaluated through the ability to lower the pH due to glycolysis. Besides, eight genotypes previously isolated from in situ dental biofilms formed during three days were grown as in vitro biofilms, and these genotypes were evaluated regarding their acidogenicity, cariogenic potential and ability to synthesize extracellular polysaccharides. In relation to genotypes isolated from in vivo biofilms, those isolated from biofilms formed in the presence of sucrose were more acid-tolerant, either at pH 5.0 or at pH 2.8, and more acidogenic, since they showed lower values of final pH during the evaluation of the curve of pH fall and also higher ability to produce acids in the first 15 minutes of glucose fermentation, than genotypes isolated from in vivo biofilms formed in the absence of sucrose. Besides, no expressive differences regarding F-ATPase activity between these two distinct conditions were found. Genotypes found only in the presence of sucrose were more acidogenic than those found only in the absence of this carbohydrate. Similar data were found for genotypes isolated from in situ dental biofilms formed in the presence of sucrose, which were more aciduric and more acidogenic than genotypes isolated from biofilms formed in the absence of this carbohydrate. In in vitro biofilm model, no differences either in the acidogenicity or in the ability of genotypes to synthesize extracellular polyssacharide were found. However, the S. mutans genotypes showed distinct cariogenic potential, independent of the fact that these genotypes had been isolated in the presence or absence of a high cariogenic challenge. The results suggest that frequent pH fall due to sucrose exposure may select more virulent S. mutans genotypes. Besides, distinct S. mutans genotypes may show distinct cariogenic potential. / Doutorado / Cariologia / Doutor em Odontologia

Orientador: Antonio Wilson Sallum / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-25T11:08:36Z (GMT). No. of bitstreams: 1 Tubel_CarlosAlbertoMalanconi_M.pdf: 5126326 bytes, checksum: 8ec90877f813bc397dc2f1e329110380 (MD5) Previous issue date: 1999 / Resumo: O objetivo dessa pesquisa foi avaliar o controle químico-mecânico da placa bacteriana em pacientes submetidos ao tratamento ortodôntico, através da escovação associada a um dentifrício contendo Triclosan-Gantrez-Citrato de Zinco-Pirofosfato de Sódio, quando comparado um dentifrício placebo. Foi realizado um estudo paralelo duplo cego, utilizando uma amostra de 69 pacientes do curso de Especialização em Ortodontia, na Faculdade de Odontologia da Universidade Metropolitana de Santos, tratados pela técnica do Arco Reto (filosofia de Roth), leucodermas, de ambos os sexos, na faixa etária de 12 a 25 anos, com idade média de 14 anos, apresentando dentadura permanente completa, portadores de maloclusão Classe I e Classe II, divisão 1 e 2 de Angle, sendo orientados e supervisionados para realizarem a escovação (técnica de BASS modificada) juntamente com o dentifrício designado. o.s pacientes foram aleatoriamente divididos em dois grupos: grupo A (controle) com escovação associada a um dentifrício placebo; grupo B (teste) com escovação associada a um dentifrício contendo Triclosan. Durante a pesquisa foram realizadas cinco avaliações, sendo a primeira realizada antes da instalação do aparelho ortodôntico fixo; as demais avaliações foram avaliadas nos seguintes períodos 5, 10, 15 e 20 meses, após a instalação do aparelho ortodôntico fixo, onde foram registrados o índice de placa de SILNESS & LÓE 'POT. 93' e o índice gengival de LÓE & SILNESS 'POT. 57', de todos os pacientes, nas diferentes épocas. Para a análise estatística foi usado o teste não paramétrico de Wilcoxon. Conclui-se que: 1. A colocação do aparelho ortodôntico fixo favoreceu o aumento do índice de placa e índice gengival em ambos os grupos no período de 5 meses, em média 25%; 2. O índice de placa bacteriana do grupo controle diminuiu 43% no grupo teste 51 % do início ao término do experimento, não sendo esses valores estatisticamente significantes. 3. O índice gengival do grupo controle diminuiu 20% e do grupo teste 45%, do início ao término do experimento, sendo esses valores estatisticamente significantes. 4. Tanto o grupo teste como o grupo controle apresentaram-se eficientes no controle da placa bacteriana, o grupo teste apresentou melhora estatisticamente significante nos índices gengivais quando comparado ao grupo controle; 5. A. escovação mecânica pareceu ser o melhor meio no controle da remoção da placa bacteriana e manutenção da saúde dos tecidos gengivais; 6. O controle químico-mecânico da placa bacteriana e inflamação gengival associada a um dentifrício contendo Triclosan-Gantrez - Pirofosfato de Sódio - Citrato de Zinco mostrou uma redução estatisticamente significante quando comparado a um dentifrício placebo na redução da placa bacteriana supragengival, sangramento gengival e gengivite marginal / Abstract: The aim of the present investigation was to examine the supragingival plaque control in patients undergoing orthodontic treatment, through oral hygiene associated to a dentifuce containing Triclosan-gantrez-zinc citrate-sodium pyrophosphate, compared to a placebo dentifrice. It was a double blind cross over clinical study conduced on 69 patients of the Metropolitan University of Santos. All of them were Brazilian caucasian, from both sexes. The age range 12 to 25 years old, and has either Class I or Class II malocclusions. They were adequately oriented and supervised to perform oral hygiene associated to a dentifrice containing Triclosan or placebo. The patients were stratified into 2 groups: group A (control) with oral hygiene associated to a dentifrice placebo group B (test) with oral hygiene associated to a dentifuce containing Triclosan. During the present investigation were performed 5 trial, being the first before the orthodontic appliance were installed; the orthers one were after a period the 5, 10, 15 and 20 months, after the appliance were installed. The purpose of theses avaluations was to appraise any alterations in the plaque index (according to Silness & Lõe) and in the gingival index (according to Lõe & Silness). To the statistic analysis was used the non-parametric test, named Wilcoxon. Based on the analysis of the results obtained, we concluded that: 1. The orthodontic appliance increased the plaque and gingival index, in both groups at phase 5 months, mean 25%. 2. The plaque index in the control group decreased 43% and the test group 51% from begining to the end ofthe study, not being this values statistically significant. 3. The gingival index in the control group decreased 20% and in the group test 45%, form begining to the end ofthe experiment, being this values statistically significant. 4. Both test and control group showed satisfatory on plaque control, test gr-oup was statistically significant on gingival index when compared to control group. 5. Mouthbrushing showed to be the best way on plaque remotion and healthy stability of gingival tissues. 6. The plaque and gingival control associated to a dentifrice containg Triclosan-gantrez zinc citrate-sodium pyrophosphate showed decreased statistically significant when compared a placebo dentifrice on supragingival index, gingival bleeding and marginal gingivitis / Mestrado / Ortodontia / Mestre em Odontologia

The plaque reduction neutralization test (PRNT) is a confirmatory diagnostic assay that is used to confirm a variety of diseases. The performance of PRNT requires the use of infectious wild type viruses, which increases the risk of laboratory acquired infections. For instance, eastern equine encephalitis (EEEV) is a highly virulent pathogen used in PRNT that can result in potentially fatal neurological diseases among humans and equines. Therefore, arboviral PRNT must be performed in Biosafety Level 3 (BSL-3) containment facilities and may require select agent approved scientists, like in the case of EEEV. These stringent requirements restrict the ability of public health laboratories to conduct PRNTs. Chimera viruses, recombinant constructs that have been bio-engineered to express the immunogenic structural proteins from the wild type virus in an attenuated form, can serve as a substitution for infectious viruses when performing PRNT. Since chimera viruses do not require the use of a BSL-3 facility and are not classified as select agents, their use offers advantages over wild type viruses. This study aimed at validating the use of EEE and West Nile chimera viruses as an alternative to the corresponding wild type viruses for diagnostic purposes at the Florida Department of Health (FDOH) Bureau of Public Health Laboratories (BPHL). These evaluations were conducted using human and avian sera. The results illustrate that chimera virus-based PRNT portrays specificity comparable to that of the wild type virus, while a slight reduction in sensitivity was observed when human sera was used. Considering their benefits in increasing safety and reducing regulatory requirements, these chimera viruses are an important alternative to the virulent wild type viruses and could be highly beneficial for diagnostic laboratories.

>Magister Scientiae - MSc / There are limited reports on virus population in haloalkaline environments; therefore the aim of this study was to investigate the genetic diversity and biology of bacteriophage communities in these environments. Bacteria were isolated to be used as phage hosts. One bacterium from Lake Magadi and four bacteria from Lake Shala were successfully isolated from sediment samples. A further two Lake Shala bacterial hosts from the IMBM culture collection were also used to isolate bacteriophages. Bacterial isolates were identified to be most closely related to Bacillius halodurans, Halomonas axialensis, Virgibacillus salarius, Bacillus licheniformis, Halomonas venusta, Bacillus pseudofirmus and Paracoccus aminovorans. Bacteriophages were screened using all bacteria against sediment samples from both Lake Shala and Lake Magadi. One phage was identified from Lake Magadi sediments (MGBH1) and two phages from Lake Shala sediments (SHBH1 and SHPA). TEM analysis showed that these phages belong to three different dsDNA phage families; Siphoviridae (MGBH1), Myoviridae (SHBH1) and Podoviridae (SHPA). All phages showed different genome sizes on agarose gel. Due to the small genome size, phage SHPA was chosen for further investigation. Partial, genome sequence analysis showed homology to both bacterial and phage proteins. A further investigation of phage diversity in this environment is essential using metagenomic approaches to understand these unique communities.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Nephrolithiasis will affect one-in-eleven people, and more than half of those individuals will have stone recurrence within a decade of their first episode. Despite decades of biomedical research on nephrolithiasis and extraordinary advances in molecular and cell biology, the precise mechanisms of kidney stone formation are not fully understood. Currently, there are limited treatments or preventative measures for nephrolithiasis. Therefore, it is crucial to scrutinize kidney stones from a molecular and cell biology perspective to better understand its pathogenesis and pathophysiology; and to, hereafter, contribute to effective therapeutic targets and preventative strategies. Kidney stones are composed of an admixture of crystal aggregated material and an organic matrix. 80% of all kidney stones are composed of calcium oxalate (CaOx) and half of all CaOx patients grow their stones on to Randall’s plaques (RP). RP are interstitial calcium phosphate mineral deposits in the renal papilla. Thus, we developed and optimized methodologies to directly interrogate CaOx stones. CaOx stones were demineralized, sectioned, and imaged by microscopy, utilizing micro CT for precise orientation. Laser microdissection (LMD) of specific regions of stone matrix analyzed by proteomics revealed various proteins involved in inflammation and the immune response. Analyses on jackstone calculi, having arm protrusions that extend out from the body of the stone, revealed that they are a rare subtype of CaOx stone formation. Micro CT analyses on 98 jackstones showed a radiolucent, organic-rich core in the arm protrusions. Fluorescence imaging on RP stones showed consistent differences in autofluorescence patterns between RP and CaOx overgrowth regions. Moreover, cell nuclei were discovered with preserved morphology in RP regions, along with variable expressions of vimentin and CD45. In comparing spatial transcriptomic expression of reference and CaOx kidney papillae, CaOx patients differentially expressed genes associated with pathways of immune cell activation, reactive oxygen damage and injury, extracellular remodeling, and ossification. Our findings provide novel methodologies to better understand the role of molecules and cells in CaOx stone matrix. Several of the proteins and cells identified in these studies may serve as potential biomarkers, and future therapeutic targets in preventing kidney stone disease.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20621号 / 医博第4270号 / 新制||医||1023(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 山下 潤, 教授 木村 剛, 教授 渡邉 大 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: Bacteremia involving oral bacteria and the systemic inflammatory responses are mechanisms that could causally link oral and systemic diseases. Objective: To use an experimental gingivitis model (EGM) in 2 clinical studies to 1) examine the systemic inflammatory responses to dental plaque, and assess racial differences in these responses; 2) determine whether dental plaque accumulation causes bacteremia and subsequent systemic responses following toothbrushing. Additionally, a laboratory study was conducted to examine the interaction between circulating human neutrophils and Fusobacterium nucleatum. Methods: For both clinical studies, healthy adults, aged 18-31 years, were recruited. In the first study, black and white, males and females participated in a 21-day EGM; in the second study, white adults participated in a 7-day EGM. In both studies, subjects visited the clinic weekly for: 1) measurement of the plaque index (PI) and gingival index (GI); 2) collection of peripheral blood samples to evaluate systemic markers of inflammation. In the second study, to analyze bacteremic episodes during the experimental phase, peripheral blood samples were collected at baseline and at 0.5, 5, and 30 minutes post-toothbrushing. In the laboratory study, interactions between F. nucleatum and circulating neutrophils were examined using a luminol-enhanced chemiluminescence assay. Results: During the experimental phases of both clinical studies, PI and GI increased (p<0.05) with a correlation between PI and GI ≥0.79. In the first study, dental plaque accumulation resulted in a systemic response that manifested as changes (p<0.05) in the level of inflammatory markers, hematologic factors, markers of lipid metabolism, and markers of metabolic change. This systemic response differed between individuals of different gender and race. In the second study, bacteremic episodes and changes in hematologic factors were observed post-toothbrushing during the experimental phase. Activation of neutrophils with F. nucleatum, in the laboratory study, increased the levels of neutrophil chemiluminescence (p<0.05). Conclusions: Overall, the findings of these investigations may shed light on the mechanistic pathways by which oral infection may impose risk for systemic diseases and provide some evidence to support a possible causal association between oral and systemic diseases. The clinical significance of this in systemic inflammatory diseases requires further investigation.

Atherosclerosis causes hundreds of thousands of deaths in the US alone every year. Fibrous cap rupture is one of the leading causes of these fatalities. Thin cap atheromas are commonly regarded as vulnerable plaque, however the effect of calcium upon a thin fibrous cap with lipid pool is poorly understood. Some studies have shown that calcium adds to stability of the lesion, while others have proven otherwise. An article by Li et al. 2007 suggests location is the key factor. By varying the percentage of calcium and lipid within a defined region, the stress on the cap was estimated using an idealized finite element arterial model. Also the thickness of the fibrous cap was varied to determine whether the stress was solely a function of lipid percentage or a combination. Plaque, arterial wall, lipid, and calcium were modeled using linear elastic, isotropic, and incompressible material properties. The first test varied the thin cap thickness from 65 to 500 microns and tested the calcified lipid model at varying lipid/calcium percentages. The lipid/Calcium pool increased/decreased 10% each test. As the cap thickness becomes thinner than 100 microns, the stress level increases rapidly. The second test compared a model with lipid pool and calcium behind the lipid with a thin cap of 65 microns to a model with lipid pool of the same size and thin cap of 65 microns but only fibrous tissue surrounding (no calcium). The lipid pool increased from 10 to 90% lipid. The result of this test found that at higher lipid percentages, the calcium increased the stress on the cap. By understanding the material properties of plaque and the structure of the lesion, future developments may be able to evaluate rupture risk. This idealized study illustrates the ability of computation models to provide insight into clinical situations.

No description available.