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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.
1

A study of the saliva with special reference to its ammonia and inorganic phosphorus concentrations

Evans, Mervyn Wyke, 1907- January 1942 (has links)
Preliminary investigations commenced in 1937, quantitive experiments conducted in 1940 / 220 leaves / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (D.D.S.)--University of Adelaide, 1963
2

A study of the saliva with special reference to its ammonia and inorganic phosphorus concentrations.

Evans, Mervyn Wyke, January 1900 (has links) (PDF)
Thesis (D.D.S.)--University of Adelaide, 1963. / Preliminary investigations commenced in 1937, quantitive experiments conducted in 1940.
3

A comparative study of the salivary pH of the normal speaker and stutterer

Hafford, Jeannette Craver. January 1942 (has links)
Thesis (M.A.)--University of Wisconsin--Madison, 1942. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 32-35).
4

The chemical composition of human saliva.

Chauncey, Howard Haskell January 1955 (has links)
Thesis (Ph.D.)--Boston University. / Whole saliva obtained immediately on arising, before brushing of the teeth, eating, or mouth rinsing was examined for enzyme activity. The enzymes measured were acid phosphatase, alkaline phosphatase, total esterase, pseudocholinesterase, lipase, aryl-sulfatase, beta-D-galactosidase, beta-glucuronidase, hyaluronidase, and lysozyme. Hyaluronidase activities of the saliva samples were determined by a modification of the viscosimetric method. Lysozyme activities were measured turbidimetically. The remaining enzyme activities were determined by the colorimetric methods of Seligman and his co-workers, modified for use with saliva. The measurement of a spectrum of enzymes using various esters and derivatives of a single chromogenic substance, beta-naphthol, afforded a means of comparing the enzyme activities of saliva, while the simultaneous determination of ten enzymes on the same saliva sample permitted evaluation of the possible interrelationship between individual enzyme systems. Sterile parotid saliva, obtained by cannulation with a parotid cap, was shown to contain acid phosphatase, esterase, pseudocholinesterase, lipase, beta-glucuronidase, and lysozyme. The acid phosphatase activity of parotid saliva was 1O% of that found in whole saliva. Cholinesterase represented 60% of the activity of whole saliva. Parotid saliva contributed about 1% to the whole saliva total esterase activity, while parotid lipase was approximately 1O% of the whole saliva lipase titer. Parotid beta-glucuronidase was from 5-20% of the amount found in whole saliva. Only with lysozyme was the activity of parotid saliva higher than that found in whole saliva. Broth cultures of whole saliva indicated that all but sulfatase and lysozyme could be produced by the microorganisms normally inhabiting the oral cavity. These findings indicated that the parotid gland secretion contributed a part of six of the ten enzymes present in whole saliva, with the remaining share of these six enzymes apparently derived from the oral flora, cellular debris, or the other salivary glands. In order to determine further the part-whole relationship of the parotid secretion to whole saliva, various inorganic, organic, nitrogenous and enzymic components of stimulated whole and parotid saliva were measured. An aqueous mouth rinse was employed to minimize the effect of oral microorganisms and cellular debris. One enzyme, beta-glucuronidase, was determined in whole saliva both before and after the washing process as an indicator for the effectiveness of the mouth rinse. Blood obtained from the test subjects was examined for enzyme titer so that serum and saliva enzyme levels could be compared using the same substrate for both, while the saliva levels for calcium, sodium, potassium, chloride, bicarbonate, phosphorus, lactic acid, and non-protein nitrogen, total proteins, albumins, and globulins could be compared to established normal serum values. In measuring the effect of mouth rinsing on the whole saliva enzyme levels it was found that the beta-glucuronidase level decreased 40% after washing. Similarly, acid phosphatase values showed a 29% decrease from the values found in the group which did not have the preliminary mouth washing. Two tests, the chi square goodness of fit and a plot of the distribution, of each of the saliva and serum components measured, were used together in a combined judgment in order to gauge the normality of the distribution. Seven (total esterase, lipase, cholinesterase, total proteins, globulins, organic phosphorus, and lactate) of the twenty-one factors measured in whole saliva were abnormally distributed; six (total esterase, lipase, total proteins, albumins, globulins, and potassium) of the twenty factors determined in parotid saliva were found to have an abnormal distribution; while one of the serum enzymes, beta-glucuronidase, proved to be abnormal. The remaining components for whole saliva, parotid saliva, and serum could thus be considered normally distributed populations. Measurement of the various salivary components indicated that whole saliva was higher than parotid saliva in regard to the calcium, inorganic phosphorus, albumins, non-protein nitrogen and hydroxyl ion contents; while the parotid secretion contained greater amounts of sodium, potassium, chloride, bicarbonate, organic phosphorus, lactic acid, total proteins and globulins. An analysis of the difference between the means of each variable in parotid saliva versus its counterpart in whole saliva was made. With the exception of chloride, inorganic phosphorus, organic phosphorus, albumins, and lactic acid a significant difference existed between the mean whole saliva level and the mean parotid saliva level. Human serum normally maintains an anionic and cationic balance of approximately 155 milli-equivalents per liter, with little variation except during marked acidosis, alkalois, or excessive salt excretion. Whole saliva had a mean total anion content of 37.7 +/- 12.0 mEq/liter and a mean total cation content of 40.7 +/- 12.8 mEq/liter. The mean total anion content of parotid saliva was 47.4 +/- 19. 2 mEq/liter, while the mean total cation content was 43. 9 +/- 17. 1 mEq/L. Saliva thus contained approximately 25% of the ionic content of serum. When the individual salivary components were compared to their serum counterparts it was found that only the potassium and inorganic phosphorus levels of whole and parotid saliva and the calcium level of whole saliva were greater than normal serum values. It was noted that parotid saliva contained relatively high levels of acid phosphatase and total esterases. The acid phosphatase levels of the parotid secretion were found to be similar in titer to those present in human serum. It was these findings which led to the study of the properties of the parotid saliva phosphomonoesterase and total esterase. Characterization of these enzymes thus permitted comparison with similar enzymes present in the other body tissues and aided in their identification. The pH activity curve for the phosphomonoesterase was determined over the range pH 2.70-5.98 in 1.2 M acetate buffer at a substrate concentration of 8.9 x 10^-4 M. Results indicated that the pH optimum for parotid saliva acid phosphatase was 4.57 with beta-naphthyl phosphate as substrate. The reaction rate followed zero order when the substrate concentration was sufficiently high. When the initial substrate concentration was lowered there was a deviation from zero order as the reaction proceeded. If the initial substrate was further decreased and increased amounts of enzyme employed the reaction tended to follow those of a monomolecular reaction, or first order, Using the method of Lineweaver and Burk a plot of S (substrate concentration) against S/V (substrate concentration/ velocity of reaction) the Michaelis constant, Km, was found to have a value of 2 x 10^-4 M. The energies of activation and inactivation were determined for the salivary phosphomonoesterase at the pH optimum. Enzyme activity was measured at nine temperatures over 25 and 55°C. The energy of activation was between 6,600 and 7,600 cal./mole., while the energy of inactivation was found to be between 32,900 and 35,900 cal. /mole. The temperature coefficient (Q10) was 1.48. Maximum activity occurred at 47°C. Although the substrate employed for the investigation of the parotid total esterases was attacked most readily by the nonspecific esterases of liver; cholinesterase and lipase were also able to catalyze its hydrolysis. Thus it may be assumed that the cholinesterase and lipase observed in saliva, as well as any nonspecific esterase present contributed to the hydrolysis of beta-naphthyl acetate by parotid saliva. In dealing with the multiple effects caused by the simultaneous action of several enzymes on a single substrate, each enzyme having its own particular characteristics, certain deviations of the resulting data from ideal were to be expected. However, this did not occur with the total esterase activity of parotid saliva, which acted as a single enzyme. Results of the investigation indicated an optimum of pH 8.57 for parotid saliva total esterases. When a sufficiently high initial substrate concentration was employed the reaction was zero order up to six hours. Longer periods of incubations could not be employed due to the high degree of spontaneous hydrolysis encountered. The Michaelis-Menten constant was calculated to be 14.48 x 10^-4 M. A linear relationship between saliva volume and the amount of beta-naphthyl acetate hydrolyzed was observed. The energy of activation was 5,860 calories/mole. Maximum activity occurred at 60°C. The temperature coefficient (Q10) of the interval 25-35 degrees C was 1.69, while a QlO of 1.38 was observed for the interval 35-45 degrees C.
5

Interação dos sistemas ABO, Lewis e fatores grupo-especificos da saliva e sua importancia pericial

Daruge Junior, Eduardo, 1960- 17 June 1998 (has links)
Orientador: Roberto Jose Gonçalves / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-23T22:39:50Z (GMT). No. of bitstreams: 1 DarugeJunior_Eduardo_D.pdf: 1950659 bytes, checksum: 06c4dd621c35af1c251b053c84bee0d8 (MD5) Previous issue date: 1998 / Resumo: Até a presente data, vários trabalhos foram realizados no sentido de investigar a existência ou não de uma interação entre os grupos sanguíneos do Sistema ABO, os fenotipos do Sistema Lewis e os fatores grupo-específicos secretados ou não pela saliva humana. Neste trabalho, utilizamos amostras de sangue e de saliva de 60 indivíduos que compareceram na Faculdade de Odontologia de Piracicaba-UNICAMP, para se submeterem a exames de investigação de paternidade por determinação judicial. Após a utilização das referidas amostras, o restante do material foi empregado neste experimento. A partir das amostras de suspensão de hemácias foram tipados os antígenos do Sistema ABO, isto é, os tipos sanguíneos A, B, AB e °, os Fatores Rh positivo e negativo, os fenótipos do Sistema Lewis (Lea e Leb) e a substância H, utilizando-se os soros Anti-A, Anti-B, Anti-Lea, Anti-Leb e soro de Lectina Anti-H, todos adquiridos da Biotest S/A. Todos os testes foram realizados de acordo com as técnicas preconizadas pelo fabricante dos soros empregados neste experimento, tendo sido feitos controles, com suspensão de hemácias já conhecidas e fornecidas gentilmente pela Biotest S/A, evitando-se assim erros na interpretação dos resultados. A determinação da função secretora ou não secretora das substâncias ABH, foi realizada pela técnica da isoaglutinação descrita por FERREIRA (13) e por BEIGUELMAN(3). Os resultados comprovam a existência de uma interação entre o fenotipo Leb e a função secretora das substâncias ABH, pois não foi identificado nenhum caso, na amostra estudada, de secretor com fenotipo Lea+. A funcão não secretora destas substâncias. pela saliva humana. está mais relacionada com o fenotipo Lea, embora verificamos alguns casos de indivíduos não secretores com os fenotipos Lea-b-. Nos indivíduos pertencentes ao grupo sanguíneo AB, verificamos que a função secretora ou não secretora, dos fatores grupo-específicos da saliva, constitui uma especificidade dos fenotipos A e B, de forma totalmente independente / Abstract: Up to now, many studies have been carried out aiming to find out whether there is an interaction among blood types (ABO system), Lewis system phenotype and group-specific factors (either produced by human saliva or not). In this study we utilized blood and saliva samples from sixty persons who carne to this faculty to do paternity investigation exams under judicial determination. After using the sample for this purpose, the surplus of the sample was used for this research. From red blood cells suspension samples we determined the antigens of ABO system, i.e., blood types (A, B, AB or O), Rh (positive) and rh (negative) factors, Lewis system phenotypes (Lea e Leb), and the H substance, using Anti-A, Anti-B, Anti-Lea and Anti-Leb serum, and Anti H Lecithin serum, ali of them acquired from Biotest S/A. Ali the tests were done according to the manufacturer's instructions. The control was done with blood red cells suspensions given by Biotest S/A, so that we avoided result interpretation errors. The determination of secretory or non-secretory function of substances ABH was achieved through isoagglutination technique as described by FERREIRA(13) and by BEIGUELMAN (3). The results have confirmed the interaction between phenotypes Leb and the secretory functions of substances ABH, because no cases were found of secretory function with phenotype Lea+. The non-secretory function of these substances, from saliva, was mainly related to phenotypes Lea although we verified a few cases of non-secretory individuais with Lea-b- phenotypes. In AB blood type individuais we verified that the secretory or non secretory function from group-specific factors from saliva is specific of phenotypes A and B, in a totaUy independent way / Doutorado / Odontologia Legal e Deontologia / Doutor em Ciências
6

Caracterização do sistema de dois componentes SptRS de Streptococcus sanguinis com possível papel na viabilidade em saliva humana : Characterization of the component system SptRS of Streptococcus sanguinis with putative role in bacterial viability in human saliva / Characterization of the component system SptRS of Streptococcus sanguinis with putative role in bacterial viability in human saliva

Camargo, Tarsila Mendes de, 1982- 24 August 2018 (has links)
Orientador: Renata de Oliveira Mattos Graner / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-24T21:23:04Z (GMT). No. of bitstreams: 1 Camargo_TarsilaMendesde_D.pdf: 3797669 bytes, checksum: f0bf38a8e753cc57e8da2546f30b5b31 (MD5) Previous issue date: 2014 / Resumo: Streptococcus sanguinis é colonizador comensal da superfícies dos dentes e patógeno comum de endocardite bacteriana em seres humanos. A colonização da cavidade oral por S. sanguinis depende, em parte, de interações de superfície bacteriana com componentes adsorvidos na superfície dos dentes (que são principalmente de origem salivar) chamado película adquirida (PA). Além disso, os produtos do metabolismo aeróbio de S. sanguinis, por exemplo, peróxido de hidrogênio, inibe o crescimento de espécies de estreptococos concorrentes e promove a liberação de DNA genômico, um componente da matriz extracelular do biofilme dental. S. sanguinis se adapta fisiologicamente a saliva durante suas fases de colonização na cavidade oral, que provavelmente envolve alterações dinâmicas em seu transcriptoma. Transcriptomas bacterianos são regulados pelos sistemas de dois componentes (SDC), que consistem de uma membrana sensora de histidina quinase (HK) e um regulador de resposta intracelular cognato (RR). A HK sofre autofosforilação sob estímulos específicos e fosforila RR cognato, que por sua vez se liga às regiões reguladoras de genes alvo, induzindo ou reprimindo a transcrição. S. sanguinis SK36 tem um ortólogo de SDC SptRS designado (de Saliva persistência) envolvidos na sobrevivência e persistência na saliva humana em S. pyogenes. O objetivo deste estudo foi investigar o papel do SDC SptRS na biologia de S. sanguinis. Para isso, mutantes knockout de sptR (SKsptR-) e sptS (SKsptS-) foram obtidos a partir da cepa SK36. Mutantes sptRS foram analisados quanto ao crescimento planctônico e biofilme em meio suplementado ou não com saliva humana. Liberação de DNA, produção de peróxido de hidrogênio, autólise e sensibilidade ao stresse oxidativo também foram analisados nestas cepas. Alterações da transcrição dos genes associados a fenótipos observados foram avaliadas por meio de RT - qPCR. Sob aerobiose, mutantes sptRS formaram cadeias muito longas e agregados de cocos. O crescimento mais lento em comparação com SK36 também foi observado. Por outro lado, um aumento significativo (cerca de 2 vezes ) em biomassa do biofilme foram encontrados em mutantes em comparação com SK36 na presença de saliva. Consistentemente, mutantes liberaram 2 a 5 vezes mais DNA ao meio e produziram 2 a 3 vezes mais de H2O2 em comparação com a cepa selvagem. Não foram observadas alterações em autólise induzida por alta temperatura. Os mutantes mostraram um aumento da tolerância ao stresse oxidativo, mas reduções de 1 a 2 logs na contagem de células (ufc / ml ) durante a incubação em saliva. A análise de RT- qPCR revelou que SptRS regula negativamente os genes que codificam as hidrolases mureína (SSA_0094 e cwdP); aumentos de 2,14 e 14,7 vezes nestes genes foram respectivamente observados em mutantes SKsptR-. Além disso, nos mutantes sptRS foram observados aumentos de 15,5 a 27,9 vezes em transcritos do gene spxB, que codifica a oxidase piruvato necessária para a produção de H2O2. Outros genes associados com a produção H2O2 também foram afetados nos mutantes [ackA (aumento de 5,3-9,7 vezes); tpK (aumento de 12,19 vezes)]. Este estudo fornece evidências de que SptRS regula as funções de S. sanguinis de estabelecimento em biofilmes associados à produção de H2O2 e liberação de DNA, e participa da sobrevivência das bactérias na saliva humana / Abstract: Streptococcus sanguinis is commensal colonizer of tooth surfaces and common pathogen of bacterial endocarditis in humans. The colonization of the oral cavity by S. sanguinis depends in part, on bacterial surface interactions with components adsorbed to tooth surfaces (which are primarily of salivary origin) called acquired pellicle (AP). In addition, products of S. sanguinis aerobic metabolism, e.g. hydrogen peroxide, inhibits the growth of competitor streptococcal species and promotes the release of genomic DNA, a component of the extracellular matrix of dental biofilms. S. sanguinis physiological adaptation to saliva during the stages of colonization of the oral cavity, likely involves dynamic changes in its transcriptome. Bacterial transcriptomes are regulated by two-component systems (TCS), which consist of a membrane sensor histidine kinase (HK) and a cognate intracellular response regulator (RR). The HK undergoes autophosphorylation under specific stimuli and phosphorylates the cognate RR, which in turn binds to regulatory regions of target genes, inducing or repressing transcription. S. sanguinis SK36 strain has an orthologue of the TCS designated SptRS (of Saliva persistence) involved in survival and persistence in human saliva in S. pyogenes. The aim of this study was to investigate the role of SptRS TCS in S. sanguinis biology. To that purpose, knockout mutants of sptR (SKsptR-), and sptS (SKsptS-) genes were obtained in strain SK36. SptRS mutants were analyzed regarding to planktonic and biofilm growth in medium supplemented or not with human saliva. DNA release, production of hydrogen peroxide, autolysis and sensitivity to oxidative stress were also analyzed in these strains. Transcriptional changes in genes associated with observed phenotypes were then assessed by RT-qPCR. Under aerobiosis, sptS/R mutants formed extremely long chains and aggregates of cocci. Slower growth compared to SK36 was also observed. On the other hand, significant increases (about 2-fold) in biofilm biomass were found in mutants compared to SK36 in the presence of saliva. Consistently, mutants released 2 to 5-fold more DNA to medium and produced 2 to 3-fold more H2O2 compared to parent strain. No changes were observed in autolysis induced by high temperature. Mutants showed increased tolerance to oxidative stress, but reductions of 1 to 2 logs in cell counts (cfu/ml) during incubation in saliva. RT- qPCR analysis revealed that SptRS negatively regulates genes encoding murein hydrolases (SSA_0094 and cwdP); increases of 2.14 and 14.7-folds in these genes were respectively observed in SKsptR mutants. In addition, 15.5 to 27.9-fold increases in sptR/S mutants were observed in spxB transcripts, which encode pyruvate oxidase required for H2O2 production. Other genes associated with H2O2 production were also affected in mutants [ackA (5.3 to 9.7-fold increases; tpK (12.19-fold increase)]. This study provides evidence that SptRS regulates functions for S. sanguinis establishment in biofilms associated with H2O2 production and DNA release, and participates in bacterial survival in human saliva / Doutorado / Microbiologia e Imunologia / Doutora em Biologia Buco-Dental
7

Inter-subject variation in the physical and/or chemical properties of human saliva this thesis submitted in partial fulfillment ... in pediatric dentistry ... /

English, Marie J. January 1987 (has links)
Thesis (M.S.)--University of Michigan, 1987.
8

Studies on salivary glycoproteins

Ericson, Thorild, January 1968 (has links)
Akademisk avhandling--Karolinska institutet, Stockholm. / Extra t.p., with thesis statement, inserted. Six articles by the author reprinted from Advances in fluorine research and dental caries prevention Arkiv för Kemi, Helv. odont. acta; Caries research and Acta odontologica Scandinavica laid in. Bibliography: p. 17-[20].
9

Inter-subject variation in the physical and/or chemical properties of human saliva this thesis submitted in partial fulfillment ... in pediatric dentistry ... /

English, Marie J. January 1987 (has links)
Thesis (M.S.)--University of Michigan, 1987.
10

Studies on calcium and inorganic phosphate in human parotid saliva

Lagerlöf, Folke. January 1982 (has links)
Thesis (doctoral)--Karolinska Institutet, Stockholm, 1982. / Extra t.p. with thesis statement inserted. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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