Os tumores de glândula salivar compreendem em torno de 2 a 6,5% dos tumores de cabeça e pescoço. Entre os tumores de glândula salivar, o adenoma pleomórfico é benigno e o mais comum. O carcinoma adenoide cístico e adenocarcinoma polimorfo de baixo grau encontram-se entre os mais frequentes malignos. Jab1 é uma de muitas proteínas que afetam diversos estágios da tumorigênese sendo importante na regulação variadas vias de sinalização e/ou proteínas como p27 e AP-1, a última composta por c-jun e c-fos, que são principalmente relacionadas com o ciclo celular e proliferação celular. O objetivo desse trabalho foi avaliar a expressão imuno-histoquímica das proteínas Jab1, p27, c-jun e c-fos no adenoma pleomórfico, adenocarcinoma polimorfo de baixo grau e carcinoma adenoide cístico das glândulas salivares. Foi realizada análise imuno-histoquímica semi-quantitativa das células marcadas nos tumores de glândula salivar e glândula salivar normal de acordo com o escore 0 (células sem expressão), 1(> 0 <= 5% de células marcadas), 2 (> 5 <= 50%) and 3 (> 50%). Para Jab1, c-jun e c-fos foi considerado apenas marcação nuclear e para p27, nuclear e citoplasmática, separadamente. Os resultados foram analisados utilizando-se os testes de Kruskal-Wallis, de Mann-Whitney, do Qui-quadrado e o teste de correlação de Spearman, cujo nível de significância foi de p<0,05 e processados com o auxílio do software GraphPad Prisma 5.0. A análise estatística revelou que a expressão de Jab1 foi significante no adenoma pleomórfico e no carcinoma adenoide cístico em relação aos ductos e no adenocarcinoma polimorfo de baixo grau em relação ao carcinoma adenoide cístico (p=0,0136, 0,0001 e 0,0344, respectivamente); a expressão de p27 nuclear foi significante no adenoma pleomórfico e no adenocarcinoma polimorfo de baixo grau quando comparados ao carcinoma adenoide cístico (p=0,0074 e 0,0004, respectivamente) e a expressão citoplasmática em todos os grupos quando comparados aos ácinos; c-fos, a expressão foi significativa nos ductos ao compará-los ao adenoma pleomórfico, adenocarcinoma polimorfo de baixo grau e carcinoma adenoide cístico (p=0,0002, 0,0048 e 0,0352, respectivamente). O teste de correlação de Spearman de Jab1, p27, c-jun e c-fos em cada lesão separadamente revelou que no adenoma pleomórfico houve correlação significativa entre Jab1 e p27 (r=0,371; p=0,020) e entre c-jun e c-fos (r=0,452; p=0,004). No adenocarcinoma polimorfo de baixo grau, houve correlação entre Jab1 e p27 (r=0,494; p=0,044) e no carcinoma adenoide cístico, entre p27 e c-fos (r=0,513; p=0,035). Foi concluído que a tumorigênese do adenoma pleomórfico, adenocarcinoma polimorfo de baixo grau e carcinoma adenoide cístico parece estar associada à expressão de Jab1 e p27. / Salivary gland tumors comprise about 2 to 6.5% of the head and neck tumors. Among the salivary gland tumors, pleomorphic adenoma is the most common and benign tumor. Adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma are the most frequent malignant tumors. Jab1 is one of many proteins which affects many stages of the tumorigenesis and regulates positively and negatively several pathways and/or proteins such as p27 and AP-1, the latter composed by c-jun and c-fos, which are mostly related to cell cycle and cell proliferation. The aim of this study was to evaluate the immunoexpression of the proteins Jab1, p27, c-jun and c-fos in pleomorphic adenoma, polymorphous low-grade adenocarcinoma and adenoid cystic carcinoma of the salivary glands. The semi-quantitative immunohistochemical analysis was performed in salivary gland tumors and in normal salivary gland according to the score 0 (no stained cells), 1 (> 0 <= 5% of stained cells), 2 (> 5 <= 50%) and 3 (> 50%). Nuclear immunostaining alone was considered for Jab1, c-jun and c-fos proteins and cytoplasmic and nuclear staining for p27. Results were analyzed in GraphPad Prisma 5.0 software using Kruskal-Wallis, Mann-Whitney and Chi-square tests and Spearman correlation test in which significancy level was p<0,05. Statistical analysis revealed that Jab1 expression was significant in pleomorphic adenoma and adenoid cystic carcinoma in relation to ducts and in polymorphous low-grade adenocarcinoma in relation to adenoid cystic carcinoma (p=0,0136, 0,0001 e 0,0344, respectively); the p27 nuclear expression was significant in pleomorphic adenoma and in polymorphous low-grade adenocarcinoma when compared to adenoid cystic carcinoma (p=0,0074 e 0,0004, respectively) and cytoplasmic immunostaining was significant in all groups when compared to acini; c-fos expression was significant in ducts if compared to pleomorphic adenoma, polymorphous low-grade adenocarcinoma and adenoid cystic carcinoma (p=0,0002, 0,0048 e 0,0352, respectively). Spearman correlation test to Jab1, p27, c-jun and c-fos in each lesion separately revealed significant correlation between Jab1 and p27 (r=0,371; p=0,020) and c-jun and c-fos (r=0,452; p=0,004) in pleomorphic adenoma. There was correlation between Jab1 and p27 (r=0,494; p=0,044) in polymorphous low-grade adenocarcinoma and between p27 and c-fos (r=0,513; p=0,035) in adenoid cystic carcinoma. In conclusion, tumorigenesis in pleomorphic adenoma, polymorphous low-grade adenocarcinoma and adenoid cystic carcinoma seems to be associated to expression of Jab1 and p27.

Mosquitos são os mais importantes vetores de patógenos humanos, transmitindo um amplo espectro de doenças infecciosas emergentes e reemergentes. Nesse cenário, o mosquito Aedes aegypti está entre as espécies mais relevantes. No presente estudo investigamos as atividades do extrato de glândula salivar (EGS) desse mosquito vetor na biologia das células dendríticas e dos linfócitos T. Nossos dados revelam que o EGS não interfere na diferenciação, maturação e função de células dendríticas murinas. Entretanto, componentes salivares desse mosquito possuem um efeito direto sobre linfócitos. O mecanismo de ação do EGS envolveu a apoptose de células T naïve, enquanto células de memória foram mais resistentes a essa atividade. Uma molécula com peso molecular acima de 400 kDa é provavelmente a responsável por esse efeito. Em conjunto, os resultados gerados por esse trabalho contribuem com a elucidação dos efeitos biológicos da saliva de Ae. aegypti na imunidade de seus hospedeiros e, conseqüentemente, seu papel na transmissão de doenças. / Mosquitoes are the most important vectors of human pathogens, transmitting a wide range of emerging and re-emerging infectious diseases. In this scenario, Aedes aegypti is a relevant mosquito species. In the present study, we have investigated the activities of the salivary gland extract (SGE) of this mosquito vector on the dendritic cell and T lymphocyte biology. Our data reveals that the SGE does not interfere on the differentiation, maturation and function of murine dendritic cells. However, salivary components of these mosquitoes have a direct effect on lymphocytes. The mechanism of action of SGE involved apoptosis of naïve T cells, while memory cells were more resistant to this activity. A molecule with molecular weight above 400 kDa is likely responsible for this effect. .Taken together, the results generated by this work contribute to the understanding of the biological effects of Ae. aegypti saliva on the host and, consequently, its role on the transmission of diseases.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2007. / Härtill 4 uppsatser.

Made available in DSpace on 2014-12-17T15:32:33Z (GMT). No. of bitstreams: 1 MarciaCCMiguel_tese.pdf: 1534160 bytes, checksum: 1a3ec415bfaf10c088ec1ae5f6224189 (MD5) Previous issue date: 2005-05-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Pleomorphic adenoma and adenoid cystic carcinoma (ACC) consist benign and malignant neoplasm from salivary gland, respectively. These neoplasms share some characteristics, such as cellular origin and considerable production of extracellular matrix, however, with distinct biological behavior. The aim of the present study was to compare the expression of D2E1, D3E1 e D5E1 integrins in pleomorphic adenoma from minor and major salivary glands and ACCs. Furthermore, it was investigated possible differences in the expression of these integrins according to histological subtypes of ACC. Fourteen cases of pleomorphic adenoma from major salivary gland, fourteen cases from minor salivary gland and ten cases of ACC were selected. It was taken into consideration the presence or absence, localization and intensity of integrin immunoexpression. The cases of pleomorphic adenoma were grouped in order to compare the expression between the distinct neoplasms. It was observed a highly significant difference (p<0,0001) in relation to D2E1 integrin between the neoplasms since pleomorphic adenoma showed a pronounced immunostaining. It was not possible to perform statistical tests considering the D2E1 integrin expression; nevertheless, it could be observed a tendency of higher staining in pleomorphic adenoma. For comparative reasons the cases ACCs were divided in two groups: solid and tubular/cribriform. It was not detected significant differences in regard to D2E1 integrin; and statistical analysis could not be realized in relation to D3E1 and D5E integrin expression. However, it was also verified a tendency of absence or reduced expression in the solid subtype. It can be concluded that the reduced D2E1 integrin expression observed in CACs may be related to a lesser degree of cell differentiation in this neoplasm and the reduced D5E1 integrin expression can be associated with aggressive biological behavior. Moreover, the absence and/or reduced expression of the studied integrins in solid ACC suggests a role in pathogenesis and more aggressive biological behavior of this histological subtype / O adenoma pleom?rfico e o carcinoma aden?ide c?stico (CAC) representam neoplasias de gl?ndula salivar benigna e maligna, respectivamente, as quais compartilham algumas caracter?sticas como a mesma origem celular e uma marcante presen?a de matriz extracelular, apresentando, por?m, comportamentos biol?gicos distintos. O prop?sito desta pesquisa consistiu em comparar a express?o das integrinas D2E1, D3E1 e D5E1 em adenomas pleom?rficos de gl?ndula salivar menor e maior e CACs. Al?m disso, procurou investigar se havia diferen?as na express?o destas integrinas entre os subtipos histopatol?gicos do CAC. Foram selecionados 14 casos de adenoma pleom?rfico de gl?ndula salivar maior, 14 casos de gl?ndula salivar menor e 10 casos de CACs. Analisou-se a presen?a ou aus?ncia, localiza??o e intensidade de marca??o das integrinas. Os dois grupos de adenomas pleom?rficos foram reunidos em um s? para fazer a compara??o entre os dois tumores. Verificou-se que houve diferen?a estat?stica altamente significativa (p<0,0001) para a integrina D2E1 entre os dois tumores, apresentando o adenoma pleom?rfico, uma marca??o mais intensa para esta integrina. Em rela??o ? integrina D5E1 n?o foi poss?vel a realiza??o de testes estat?sticos, ficando patente, por?m, que houve uma tend?ncia da referida integrina ser mais intensamente expressa no adenoma pleom?rfico. Para an?lise comparativa, os CACs foram subdivididos em 2 grupos: s?lido e tubular/cribriforme. Para a integrina D2E1 observou-se que n?o houve diferen?a estatisticamente significativa e em rela??o ? D3E1 e D5E1 n?o foi poss?vel a realiza??o do teste estat?stico; no entanto, tamb?m foi verificada uma clara tend?ncia para os casos do subtipo s?lido apresentarem express?o ausente ou reduzida das integrinas avaliadas. Concluiu-se que a reduzida express?o da integrina D2E1 observada nos CACs, pode estar relacionada com a menor diferencia??o das c?lulas deste tumor e ? poss?vel que a reduzida express?o da D5E1, possa estar implicada em seu comportamento mais agressivo. Al?m disso, sugere-se que a aus?ncia e/ou redu??o da express?o das integrinas pesquisadas nos casos do subtipo s?lido, pode desempenhar algum papel na patog?nese e no comportamento biol?gico mais agressivo deste subtipo tumoral

No ciclo natural de transmissão da leishmaniose, as fêmeas infectadas de flebotomíneos regurgitam promastigotas na pele de hospedeiro junto com a saliva. Tem sido descrito que componentes da saliva do vetor possuem propriedades imunomodulatórias que facilitam o estabelecimento da infecção no hospedeiro, contudo a maior parte dos estudos emprega lisado de glândula salivar (LGS) de vetores colonizados em laboratório. Dessa forma, o principal objetivo deste estudo foi avaliar a especificidade do LSG dos flebotomíneos Lutzomyia flaviscutellata e Lutzomyia (Psychodopygus) complexus capturados no campo na infectividade de Leishmania (Leishmania) amazonensis e Leishmania (Viannia) braziliensis. Camundongos BALB/c foram inoculados no coxim plantar traseiro com formas promastigotas de L. (L.) amazonensis e L. (V.) braziliensis na ausência ou presença do LGS de L. flaviscutelata, e L. (P.) complexus. A evolução da infecção foi acompanhada semanalmente e biópsias do ponto de inoculação foram coletadas para análise histopatológica e determinação de carga parasitária na 4ª e 8ª semana pós-infecção (PI); e o linfonodo de drenagem para caracterização de subpopulações de linfócitos T por citometria de fluxo. Células de linfonodo de drenagem foram também cultivadas, com estímulo homólogo, para quantificação de citocinas (IL-10, IL- 12 e IL-4) no sobrenadante. A infecção por L. (L.) amazonensis e L. (V.) braziliensis não se mostrou exacerbada nos grupos co-inoculados com o LGS de ambas as espécies em relação ao grupo controle, inoculado somente com o parasito. O tamanho de lesão e carga parasitária do grupo controle foi maior ou igual aos grupos com saliva. Na infecção por L. (L.) amazonensis houve diminuição dos linfócitos CD4+ e aumento na população de linfócitos CD8+ enquanto na infecção por L. (V.) braziliensis houve manutenção da população de linfócitos CD4+ e aumento de linfócitos CD8+ em todos os grupos quando comparados ao grupo saudável. A produção de IL-10 e IL-12, não diferiram entre os grupos, assim como a produção de IL-4 no grupo infectado por L. (V.) braziliensis. No entanto, nos grupos infectados apenas com L. (L.) amazonensis e com saliva de L. flaviscutellata, foi observada uma maior produção de IL-4 em relação ao grupo saudável. De forma geral, os resultados mostraram que a saliva de L. flaviscutellata e de Lutzomyia (P.) complexus, no seu binômio natural vetor/parasito ou não, não favoreceram o estabelecimento da infecção causada por L. (L.) amazonensis e L. (V.) braziliensis em camundongos BALB/c. / During the natural transmission of leishmaniasis, the infected female phlebotomine regurgitates promastigotes into the host\'s skin together with the saliva. It has been reported that components of vector saliva contain immunomodulatory properties that facilitate the establishment of infection in the host, however the most studies employed salivary gland lysate (SGL) of laboratory colonized vectors. Thus, the main objective of this study was to evaluate the specificity of SGL of the phlebotomines Lutzomyia flaviscutellata and Lutzomyia (Psychodopygus) complexus caught in the field in the infectivity of L. (L.) amazonensis and L. (V.) braziliensis. BALB/c mice were inoculated in the hind footpad with promastigotes of L. (L.) amazonensis and L. (V.) braziliensis in the absence or presence of L. flaviscutelata, and L. (P.) complexus SGL. The evolution of the lesion size was evaluated weekly and biopsies from the site of infection were collected for histopathological analysis and determination of parasite load in the 4th and 8th week post infection (PI), and the draining lymph node to characterize subsets of T cells by flow cytometry. The draining lymph nodes cells were also cultured with specific antigen to determine the cytokines (IL-10, IL-12 and IL-4) in the supernatant. L. (L.) amazonensis and L. (V.) braziliensis infection was not exacerbated in the groups co-inoculated with the SGL of both species in the control group, only inoculated with the parasite. The lesion size and parasite burden of the control group was higher or equal to the groups with saliva. In L. (L.) amazonensis infection there was a decrease of CD4+ cells and an increase in the population of CD8+ cells while in L. (V.) braziliensis infection there was a maintenance of CD4+ cells and an increase in the population of CD8+ cells in all groups compared with the health group. The production of IL-10 and IL-12, did not differ between groups, as well as the production of IL-4 in the group infected by L. (V.) braziliensis. However, in the groups infected only with L. (L.) amazonensis in the presence of L. flaviscutellata saliva, it was observed a higher production of IL-4 in relation with the health group. As a whole, the results show that the saliva of L. flaviscutellata and L. (P.) complexus, in the natural vector/parasite binomium or not, did not favor the establishment of the infection caused by L. (L.) amazonensis and L. (V.) braziliensis in BALB/c mice

We used flow cytometry in a retrospective study of pleomorphic adenoma and carcinoma arising in pleomorphic adenoma, using paraffin-embedded tissue, to assess the relationship among proliferative activity, ploidy, and recurrence or malignant transformation. Twenty-four specimens obtained from 22 tumors were acceptable for analysis (co-efficient of variation, < or = 7.0), including multiple samples from two tumors. Fourteen tumors (13 benign and one malignant) were diploid. Six tumors were aneuploid: four benign pleomorphic adenomas and two carcinomas arising in pleomorphic adenoma. Two tetraploid tumors were malignant recurrences from the same patient. Of the recurrent tumors (nine benign and four malignant), 54% were aneuploid. The highest S-phase fractions were observed in recurrent and malignant pleomorphic adenomas. Immunostaining with p105, a nuclear proliferation antigen, revealed increased proliferative activity in a majority of pleomorphic adenomas. Increased proliferative activity and aneuploidy occurred in benign pleomorphic adenomas.

O objetivo deste estudo foi mensurar o fluxo salivar, pH, capacidade tampão, concentrações de proteína total e ácido siálico, atividades das enzimas amilase e peroxidase e concentração dos íons sódio, potássio, cálcio, fósforo, zinco e magnésio em saliva total de indivíduos síndrome de Down com idade entre 1 e 25 anos. Nos indivíduos com idade entre 1 e 5 anos a saliva total foi coletada através de uma leve sucção, enquanto que nos outros indivíduos com idade entre 6 e 10, 11 e 15, 15 e 20, 21 e 25 a saliva total foi coletada com estimulação mecânica através da mastigação de parafilm, durante 10 minutos. O pH e a capacidade tampão foramdeterminadas usando um pHmetro digital. A capacidade tampão foi mensurada através de titulação com HCl a 0,01N. A concentração de eletrólitos foi determinada através de um espectrofotômetro de emissão atômica com fonte de excitação de argônio induzido. A proteína total foi mensurada através do reagente de Folin. A atividade da amilase foi mensurada através da produção de maltose e a atividade da peroxidase foi mensurada através da utilização de orto-dianisidina. Para a analise estatística os dados foram apresentados em media ± desvio padrão. Foi utilizado o teste “t" de Student para determinar as diferenças entre as medias dos indivíduos síndrome de Down e o grupo controle. Nenhuma diferença significante foi observada na concentração de ácido siálico, fósforo, zinco, magnésio e cálcio entre os indivíduos síndrome de Down e o grupo controle. A concentração de sódio, proteína total e a capacidade tampão demonstraram ser maior nos indivíduos com síndrome de Down em comparação ao grupo controle. Por outro lado, o fluxo salivar, a concentração de potássio, e a atividade das enzimas amilase e peroxidase foram menores no grupo síndrome de Down quando comparado ao grupo controle. Estes resultados sugerem que as pessoas com síndrome de Down apresentam alterações no metabolismo do ducto e/ou das células acinares das glândulas salivares. / The aim of this study was to measure the flow rate, pH, buffer capacity, sialic acid, total protein concentrations, amylase and peroxidase activities and sodium, potassium, calcium, phosphorus, zinc and magnesium concentration whole saliva of individuals with Down syndrome aged 1 - 25 years. In individuals aged 1-5 years the whole saliva was collected under slight suction, while in the others individuals aged 6-10, 11-15, 15-20, 21-25 the whole saliva was collected with stimulation by chewing a piece of parafilm, for 10 minutes. The pH and the buffer capacity were determined using a digital pHmeter. The buffer capacity was measured by titration with 0.01 N HCl. Electrolyte concentrations were determined by inductively coupled argon plasma with atomic emission spectrometry. Sialic acid was determined by thiobarbituric acid assay. Protein was determined by the folin’s phenol reagent. Amylase was assayed measuring the maltose produced by the breakdown of starch and peroxidase with ortho dianisidine. For statistical analysis the date are presented as mean ± SD. Student’s “t" test was used to determine differences between the mean of the Down syndrome and control groups. No statistically significant differences were observed in sialic acid, phosphorus, zinc, magnesium and calcium concentration between the individuals with Down syndrome and control group. The sodium and total protein concentration and buffer capacity showed higher in the Down syndrome than in the control group. On the other hand the flow rate and potassium concentration, amylase and peroxidase activities were lower in the Down syndrome than in the control group. These results suggest that the Down syndrome persons present alteration in the metabolism of the duct and/or acinar cells of salivary glands.

Title: The subnuclear localisation of Notch responsive genes. Candidate Name: Matthew Jones Notch signalling is a highly conserved cell-cell communication pathway with critical roles in metazoan development and mutations in Notch pathway components are implicated in many types of cancer. Notch is an excellent and well-studied model of biological signalling and gene regulation, with a single intracellular messenger, one receptor and two ligands in Drosophila. However, despite the limited number of chemical players involved, a striking number of different outcomes arise. Molecular studies have shown that Notch activates different targets in different cell types and it is well known that Notch is important for maintaining a stem cell fate in some situations and driving differentiation in others. Thus some of the factors affecting the regulation of Notch target genes are yet to be discovered. Previous studies in various organisms have found that the location of a gene within the nucleus is important for its regulation and genome reorganisation can occur following gene activation or during development. Therefore this project aimed to label individual Notch responsive loci and determine their subnuclear localisation. In order to tag loci of interest a CRISPR/Cas9 genome-editing method was established that enabled the insertion of locus tags at Notch targets, namely the well-characterized Enhancer of split locus and also dpn and Hey, two transcription factors involved in neural cell fate decisions. The ParB/Int system is a recently developed locus tagging system and is not well characterised in Drosophila. It has a number of advantages over the traditional LacO/LacI-GFP locus tagging system as it does not rely on binding site repeats for signal amplification and can label two loci simultaneously in different colours. This thesis characterised the ParB/Int system in the Drosophila salivary gland and larval L3 neuroblast. Using 3D image segmentation hundreds of nuclei were reconstructed and a volume based normalisation method was applied to determine the subnuclear localisation of several Notch targets with and without genetic manipulations of the Notch pathway.

O objetivo deste estudo foi mensurar o fluxo salivar, pH, capacidade tampão, concentrações de proteína total e ácido siálico, atividades das enzimas amilase e peroxidase e concentração dos íons sódio, potássio, cálcio, fósforo, zinco e magnésio em saliva total de indivíduos síndrome de Down com idade entre 1 e 25 anos. Nos indivíduos com idade entre 1 e 5 anos a saliva total foi coletada através de uma leve sucção, enquanto que nos outros indivíduos com idade entre 6 e 10, 11 e 15, 15 e 20, 21 e 25 a saliva total foi coletada com estimulação mecânica através da mastigação de parafilm, durante 10 minutos. O pH e a capacidade tampão foramdeterminadas usando um pHmetro digital. A capacidade tampão foi mensurada através de titulação com HCl a 0,01N. A concentração de eletrólitos foi determinada através de um espectrofotômetro de emissão atômica com fonte de excitação de argônio induzido. A proteína total foi mensurada através do reagente de Folin. A atividade da amilase foi mensurada através da produção de maltose e a atividade da peroxidase foi mensurada através da utilização de orto-dianisidina. Para a analise estatística os dados foram apresentados em media ± desvio padrão. Foi utilizado o teste “t” de Student para determinar as diferenças entre as medias dos indivíduos síndrome de Down e o grupo controle. Nenhuma diferença significante foi observada na concentração de ácido siálico, fósforo, zinco, magnésio e cálcio entre os indivíduos síndrome de Down e o grupo controle. A concentração de sódio, proteína total e a capacidade tampão demonstraram ser maior nos indivíduos com síndrome de Down em comparação ao grupo controle. Por outro lado, o fluxo salivar, a concentração de potássio, e a atividade das enzimas amilase e peroxidase foram menores no grupo síndrome de Down quando comparado ao grupo controle. Estes resultados sugerem que as pessoas com síndrome de Down apresentam alterações no metabolismo do ducto e/ou das células acinares das glândulas salivares. / The aim of this study was to measure the flow rate, pH, buffer capacity, sialic acid, total protein concentrations, amylase and peroxidase activities and sodium, potassium, calcium, phosphorus, zinc and magnesium concentration whole saliva of individuals with Down syndrome aged 1 - 25 years. In individuals aged 1-5 years the whole saliva was collected under slight suction, while in the others individuals aged 6-10, 11-15, 15-20, 21-25 the whole saliva was collected with stimulation by chewing a piece of parafilm, for 10 minutes. The pH and the buffer capacity were determined using a digital pHmeter. The buffer capacity was measured by titration with 0.01 N HCl. Electrolyte concentrations were determined by inductively coupled argon plasma with atomic emission spectrometry. Sialic acid was determined by thiobarbituric acid assay. Protein was determined by the folin’s phenol reagent. Amylase was assayed measuring the maltose produced by the breakdown of starch and peroxidase with ortho dianisidine. For statistical analysis the date are presented as mean ± SD. Student’s “t” test was used to determine differences between the mean of the Down syndrome and control groups. No statistically significant differences were observed in sialic acid, phosphorus, zinc, magnesium and calcium concentration between the individuals with Down syndrome and control group. The sodium and total protein concentration and buffer capacity showed higher in the Down syndrome than in the control group. On the other hand the flow rate and potassium concentration, amylase and peroxidase activities were lower in the Down syndrome than in the control group. These results suggest that the Down syndrome persons present alteration in the metabolism of the duct and/or acinar cells of salivary glands.

Magister Chirurgiae Dentium - MChD / Purpose: To assess the oral health status of 4-15-year-old schoolchildren in the Western Region of the Eastern Cape Province, by determining the prevalence of dental caries, periodontal disease, dental fluorosis, malocclusion and oral mucosal lesions and to create baseline data for planning oral health services in this region. Materials and Methods: The prevalent analytic survey was undertaken on 822 schoolchildren between the ages of 4-15 years in 27 different schools. The sample size selected for this region by the Department of Statistics, University of Pretoria, for the National Oral Health Survey of 1999/2000 was used. The data on 209, 210, 209 and 194 scholars in the 4-5, 6, 12 and 15-year-old age groups respectively were collected. The World Health Organization's (1997) criteria were used to determine the prevalence of caries, periodontal treatment needs, the dental fluorosis, malocclusion and prevalence of oral mucosal lesions. Six calibrated and trained examiners recorded the data on a survey form. The WHO survey forms were used for data collection. The data were analysed and processed by the author on Microsoft Excel 2000. Results: The sample size consisted of 1.35 % Asian, 51.89 % Black, 26.07 % Coloured and 20.06 % White scholars. Nearly equal amounts of males (48.3 %) and females (51.7%) were examined. The dental caries prevalence in the primary dentition of 4-5-year-olds with an average age of 4.43 years was 40.67%, with a mean dmft of 3,56. The dental caries prevalence in the permanent dentition of6-, 12- and 15-year-oldage groups was 67.62%, 46.05% and 67.92% respectively. The mean DMFT for 6-, 12- and 15 year olds were 0.05, 1.19 and 2.02 respectively. Gender differences and differences in prevalence of dental caries between the populations groups were recorded. The Coloured children experienced the highest dental caries prevalence. In the 4-5- and 15-year-old groups the males were affected more than the females by dental caries. Prevalent differences were recorded between rural and urban areas in the same population group. The prevalence of periodontal disease in 373, 12-15-year-olds was 79.09%. Only 4.02 % were in need of dental hygiene instructions and polishing. Dental education, dental hygiene instructions, dental scaling and polishing were needed by 75.07% of the children. Dental fluorosis prevalence in 450, 6-15-year-olds was 13.03%. Dental fluorosis did not affect 86.97% of the scholars; 10.63% had mild fluorosis and 2.05% was severely affected. The mean fluoride concentration in the drinking water in this region were 1.07 mgIL, ranging between 0.3-3 mgIL. Definite malocclusion was recorded in only 0.48% of the 12-year-old group, whom needed elective treatment. In the 12-year-olds, 99.52% needed no or slight treatment for no or minor malocclusions. The majority of children had no oral mucosal lesions (91.55%). The prevalence of oral mucosal lesions was 8.5% in this survey. The most frequent conditions were traumatic lesions (1.96%), dento-alveolar abscess (1.22%) and herpes labialis (1.22%). The intra-examiner reliability for caries, dental fluorosis, periodontal treatment needs and prevalence of malocclusions was 97.66%, 100%, 88.89% and 86.67% respectively. The inter-examiner reliability was 98.75%, 98.34%, 100%, 100% and 100% respectively for the five examiners. Conclusion: This survey indicated a higher prevalence of dental caries in the primary dentition (63.48%), than the permanent dentition (41.3%). The mean dmft was 3.65 and the DMFT 1.2, which indicated a low mean caries experience for these children. The WHO goal for the year 2000 for the 6-year-olds of 50% being caries free has not reached for only 32.56% were caries free. The mean DMFT of 1.2 for 12-year-olds in this survey is below the WHO goal of a mean DMFT of 1.5 or less. The lack of available preventative service provision, were ) indicated by the low percentage of fissure sealants (2.8%). The need for dental treatment was highlighted by the need mostly for one-surface restorations. Preventative treatment, two-surface fillings and extractions were also needed. Periodontal disease was a major public oral health concern for this region for a prevalence of 79.09% was recorded for the 12-15-year-olds. The majority of the children affected by periodontal disease (75.07%) were in need of professional cleaning and calculus removal. The prevalence of dental fluorosis was 8.2%, 19.87% and 13.05% for 6-, 12- and IS-year age groups respectively. The prevalence of malocclusion was 0.48% for the 12-year-old group. The prevalence of oral mucosa lesions was 8.5% for 4-15-year-old schoolchildren. Therefore, the conclusion can be made that dental fluorosis; malocclusions and oral mucosal lesions were no public concern in this region. The major public oral health concerns were dental caries in the primary dentition and periodontal disease in all age groups. Recommendations: Dental services in this region should be directed towards prevention of dental caries in the primary dentition and periodontal disease in all age groups. The focus of dental services should be primarily on preventative programs and treatments. The public dental treatments needs indicated in this survey, namely scaling and polishing, restorations and extractions, consists of the primary health care package delivery. Currently, no evaluation tool exists to monitor the efficiency of oral health programs, no baseline data for the Province exists. Therefore, the urgent need for dental research and oral health service planning and delivery are recommended.