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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.
11

Cell proliferation rate in clinically healthy oral mucosa of crack cocaine users

Matheus, Paula Daniele January 2012 (has links)
Objetivo: Avaliar a taxa proliferativa de células esfoliadas da mucosa bucal clinicamente saudável de usuários de crack. Material e Métodos: esfregaços orais foram coletados de língua e assoalho bucal de 87 indivíduos, divididos em três grupos: os usuários de crack (CRCO), n = 26; fumantes / etilistas (SA), n = 26 e controles (C ), n = 35. Lâminas histológicas foram submetidas à técnica de impregnação pela prata para quantificação do número de AgNORs/núcleo. As imagens foram obtidas por um sistema de captura de imagem adaptado a um microscópio de luz em x1000 ampliação. A média AgNOR por núcleo (mAgnor) e a percentagem de células com mais de 1,2,3 e 4 AgNORs por núcleo (pAgNOR> 1,> 2> 3 um> 4) foram calculados. Resultados: As células esfoliadas de mucosa da língua SA (3,34 ± 0,51 AgNOR / núcleo) exibiram maior taxa de proliferação celular (p <0,05) quando comparado com C (2,81 ± 0,773 AgNORs / núcleo) e CRCO (2,87 ± 0,51 AgNORs / núcleo) . Um aumento (p <0,05) da mAgnor também foi observada nas células do assoalho bucal (3,55 ± 0,57) em comparação com SA C (3,18 ± 0,53) e CRCO (3,28 ± 0,39). Dados semelhantes foram encontrados usando pAgNOR>1,>2,>3 e > 4. Conclusão: usuários de crack não apresentaram alterações na taxa proliferativa celular da mucosa bucal. Diante dos dados apresentados, o consumo de cigarro, em combinação com o consumo de álcool, continua sendo o maior fator prejudicial à mucosa bucal. / Objective: The aim of this study was to evaluate cell proliferation rate of cells exfoliated from clinically healthy mucosa of crack cocaine users. Material and Methods: Oral smears were collected from tongue and floor of the mouth mucosa of 87 individuals divided into three groups: crack cocaine users (CrCo), n=26; smokers/alcohol drinkers (SA), n=26 and controls (C), n=35. Histological slides were silver-stained using AgNOR technique to evaluate cell proliferation rate. Images were obtained by an image capturing system adapted to a light microscope at x1000 magnification. Quantification considered 50 cells by smear in which the number of AgNOR dots was visually counted. Mean AgNOR numbers per nucleus (mAgNOR) and the percentage of cells with more than 1,2,3 and 4 AgNORs per nucleus (pAgNOR>1,>2>3 an>4) were calculated. Results: Cells exfoliated from tongue mucosa of SA (3.34±0.51 AgNOR/nucleus) exhibit higher cell proliferation rate (p<0.05) when compared to C (2.81±0.773 AgNORs/nucleus) and to CrCo (2.87±0.51 AgNORs/nucleus). An increase (p<0.05) in mAgNOR was also observed in floor of the mouth cells (3.55±0.57) in SA when compared to C (3.18±0.53) and CrCo (3.28±0.39). Similar findings were found using pAgNOR>1,>2,>3 e >4. Conclusion: Crack cocaine users did not present changes in cell proliferation rate of oral mucosa. Between the expositions studied here, cigarette smoking in combination with alcohol consumption remain as the most harmful factors to oral mucosa.
12

FGF básico e seus receptores em relação à atividade proliferativa na placenta bubalina em diferentes fases da gestação / Basic FGF and its receptors in relation to proliferative activity in the buffalo placenta during gestation

Laura Pacheco Artoni 19 August 2005 (has links)
O bFGF (fator de crescimento fibroblástico básico) é um dos fatores envolvidos na organogênese placentária. O fator participa da regulação dos processos de angiogênese, de crescimento e desenvolvimento placentário e de proliferação e diferenciação das células placentárias. A homeostase tecidual requer balanço entre proliferação e morte celular. A identificação de células em atividade proliferativa pode ser feita pela detecção do antígeno Ki-67 presente no núcleo das células em proliferação. Objetivou-se estudar a distribuição espaço-temporal do bFGF e dois de seus receptores, FGFR1 e FGFR2, na placenta bubalina correlacionando-a à proliferação celular. Foram utilizadas treze placentas de fêmeas da espécie bubalina em diferentes fases da gestação, divididas em quatro grupos. Grupo 1 (n=4), placentas de 3 meses; grupo 2 (n=4), 5 meses; grupo 3 (n=1), 8 meses e grupo 4 (n=4), 9,5 meses. Para a detecção da proteína do bFGF, FGFR1 e FGFR2 bem como do antígeno Ki-67 foram realizados testes de imuno-histoquímica. Para tal, bloqueou-se a peroxidase endógena com peróxido de hidrogênio PA a 1% em metanol e as reações inespecíficas com soro eqüino. A incubação com os anticorpos primários anti-Ki-67, anti-bFGF, anti-FGFR1 e anti-FGFR2 foi feita a 4°C por vinte e quatro horas e a incubação com o anticorpo secundário universal por vinte minutos em temperatura ambiente. Foi utilizado um complexo avidina-biotina para amplificar a reação e para revelação utilizou-se Nova Red&reg;. A análise dos resultados foi feita em microscópio óptico em aumento de 400 vezes através do sistema de imagens KS-400. Utilizou-se o programa Graph Prism 4 para análise estatística dos resultados. Foi detectada a expressão da proteína do bFGF e seus receptores no núcleo e citoplasma de células do estroma e epitélio maternos e fetais da placenta bubalina de maneira tempo-dependente ao longo da gestação. A atividade proliferativa apresentou perfil decrescente do início até o final da gestação. A correlação observada entre a expressão do bFGF e do Ki-67 nas células do epitélio materno e fetal e estroma materno foi positiva (r = 0,282, r = 0,313 e r = 0,469, respectivamente; p < 0.05); entre FGFR1 e Ki-67 a correlação foi mais elevada para as células do estroma e epitélio maternos e estroma fetal (r = 0,739, r = 0,511 e r = 0,358; p<0,0001) e negativa para o epitélio fetal (r = -0.211); FGFR2 e Ki-67 a correlação foi negativa para as células epitélio materno (r = -0,027) e positiva para o epitélio e estroma fetal (r = 0,384 e r = 0,268; respectivamente; p < 0.05). Pode-se concluir a partir dos resultados obtidos que existe uma correlação positiva entre a expressão da proteína do bFGF de seus receptores 1 e 2 e o antígeno Ki-67. No entanto, essa correlação é dependente do tipo celular e da fase de gestação analisadas, e aponta para um possível envolvimento do bFGF e seu receptor 2 na proliferação do trofoblasto enquanto o receptor 1 modularia a ação de outro agente proliferativo no epitélio materno e estromas materno e fetal. / The bFGF (basic Fibroblast Growth Factor) is involved in the placental organogesis as a potent angiogenic molecule and is related to the growing and development of the placenta and proliferation of placental cells. Tissue homeostasis requires a balance between cell proliferation and cell death. The identification of proliferating cells can be made through the detection of Ki-67 nuclear antigen, present in these cells. The aim of this study was to evaluate the space-temporal expression of bFGF and two of its receptors, FGFR1 and FGFR2, in buffalo placenta in correlation to proliferative activity. In this study 13 buffalo placentas in different gestational phases were collected and divided into four groups. Group 1 (n=4), three moth-old placentas; group 2 (n=4), five month-old; group 3 (n=1), eight month-old and group 4 (n=4), 9.5 month-old. For the localization of bFGF, FGFR1, FGFR2 proteins and Ki-67 antigen, immunohistochemical assays were carried out. For that purpose, endogenous peroxidase activity was blocked with 1% Hydrogen Peroxide PA in methanol and non-specific binding with equine serum (1:10). Incubations with primary antibodies anti-Ki-67, anti-bFGF, anti-FGFR1 and anti-FGFR2 were made for 24 hours at 4°C. Incubation with universal secondary antibody (1:200) was made for 20 minutes in moist chamber at room temperature. Avidin/biotinylated horseradish ABC Elite Kit was used to amplify and Nova Red&reg; to develop the immunostaining. Slides were observed under a light microscope at 400 times magnification and photographed with KS-400 image program. Graph Prism 4.0 program was used for statistical analysis. Expression of the bFGF and its receptors proteins was detected in the nucleus and cytoplasm of buffalo placental cells during gestation. Placental proliferative activity was evaluated through the expression of Ki-67 antigen. The correlation observed between bFGF and Ki-67 expression in the maternal and fetal epithelium and maternal stroma cells was positive (r = 0,282, r = 0,313 e r = 0,469, respectively; p < 0.05). Between FGFR1 and Ki-67 the correlation was higher for maternal epithelial and stroma and fetal stroma cells (r = 0,739, r = 0,511 e r = 0,358, respectively; p<0,0001) and negative for fetal epithelium (r = -0.211). FGFR2 and Ki-67 correlation observed was negative for maternal epithelium cells (r = -0,027) and positive for fetal epithelium and stroma cells (r = 0,384 e r = 0,268; respectively; p < 0.05). We conclude that bFGF and its receptors 1 and 2 are positively correlated to the expression of the Ki-67 antigen, depending on cell type and gestational period. The results suggest that bFGF and its receptor 2 may be involved in the modulation of trophoblast proliferation, whereas FGFR1 may modulate proliferation in the maternal epithelium and fetal and maternal stroma, probably through the binding to another growth factor (s).
13

Estudo retrospectivo-sistemático e análise quantitativa da proliferação celular e apoptose; identificação da proteína conexina 43 e 26 aberrante em glândula perianal normal, hiperplásica e neoplásica em cães / Retrospective - systematic study and quantitative analysis of the cellular proliferation and apoptosis and identification of connexin 43 and aberrant 26 protein in normal, hyperplasic and neoplastic perianal glands in dogs

Ana Maria Cristina Rabello Pinto da Fonseca Martins 05 July 2006 (has links)
Duzentos e quarenta e cinco neoplasias de glândula perianal de cães dos arquivos do Departamento de Patologia da FMVZ/ USP, de 1984 à 2004, foram revisadas histologicamente. A grande maioria dos casos (34%) foi classificada como adenoma moderadamente diferenciado, grupo II, em machos com mais de oito anos de idade o que reflete a dependência androgênica dessas neoplasias. A análise quantitativa da proliferação celular e apoptose nos diferentes tipos histológicos de neoplasias, hiperplasia e tecido normal dessas glândulas determinou um padrão paralelo de aumento de ambas as quantificações. Com os resultados do índice de crescimento ajustado obtivemos que, embora os carcinomas tenham um nível de proliferação celular muito maior que os adenomas (grupo I), esses têm um potencial de crescimento maior, levando-se em conta a apoptose. Investigamos, também, a expressão de Cx43, 26 e 32 nessas glândulas perianais com métodos imunoistoquímicos. A Cx 43 expressava-se em glândulas perianais normais, hiperplásicas, adenomas (grupo I) e adenomas moderadamente diferenciados. Nos adenomas pouco diferenciados (grupo II), a expressão estava reduzida e não se expressava nos carcinomas (grupo III). A Cx 26 acumulava-se no citoplasma nas glândulas normais, hiperplásicas, adenomas (grupo I) e adenomas moderadamente diferenciados (grupo II). Nos adenomas pouco diferenciados (grupo II), a expressão estava reduzida e, ausente, nos carcinomas. A Cx 32 não foi identificada em nenhum dos grupos (I, II e III) ou glândulas normais e hiperplásicas. Concluindo, Cx 43 e Cx26 são importantes para a homeostasia de glândula perianal normal, podendo estar associadas aos receptores de andrógenos presentes em suas células. Este foi o primeiro estudo mostrando a apoptose e sua influência na fase promocional da carcinogênese e, também, o primeiro estudo mostrando a expressão de Cx43, Cx 26 citoplasmática e ausência de expressão da Cx 32 em glândulas perianais normais, hiperplásicas e neoplásicas em cães / Two hundred and forty five neoplasms of the perianal glands of dogs from the archives of the Department of Pathology of the FMVZ/USP, 1984 to 2004, have been reviewed hystologically. Most of the cases (34%) were classified as moderately differentiated adenomas, group II, in males over 8 years of age, which showed an androgenic dependence of these neoplasms. The quantitative analysis of the cellular proliferation and apoptosis, in the different hystologic types of neoplasia, hyperplasia and normal tissue of these glands, determined a parallel pattern of increase in both quantifications. The values of the net growth index showed that although carcinomas have a much higher level of proliferation than adenomas (group I), these latter have a much higher potential of growth, taking into account the effect of the apoptosis. The occurrence of Cx 43, 26 and 32 in these perianal glands was also investigated by immunohystochemical methods. Cx 43 expression was present in normal, hyperplasic, adenomas (group I) and moderately differentiated adenomas perianal glands. In poorly differentiated adenomas (group II), the expression was reduced and was absent in carcinomas. Cx 26 was accumulated in the cytoplasm in normal, hyperplasic, adenomas (group I) and moderately differentiated adenomas glands. In poorly differentiated adenomas (group II), the expression was reduced and was absent in carcinomas. Cx 32 was not found in all groups (I, II, III), normal and hyperplasic glands. In conclusion, Cx 43 and Cx 26 are important for homeostasis of normal canine perianal glands, being able to be associated with the androgen receptors present in their cells. This was the first study showing the apoptosis and its influence on the promotional phase of carcinogenesis and, also, the first study showing the occurrence of Cx 43, cytoplasmatic Cx 26 and no expression of Cx 32 in normal, hyperplasic and neoplastic canine perianal glands
14

Estudo retrospectivo-sistemático e análise quantitativa da proliferação celular e apoptose; identificação da proteína conexina 43 e 26 aberrante em glândula perianal normal, hiperplásica e neoplásica em cães / Retrospective - systematic study and quantitative analysis of the cellular proliferation and apoptosis and identification of connexin 43 and aberrant 26 protein in normal, hyperplasic and neoplastic perianal glands in dogs

Martins, Ana Maria Cristina Rabello Pinto da Fonseca 05 July 2006 (has links)
Duzentos e quarenta e cinco neoplasias de glândula perianal de cães dos arquivos do Departamento de Patologia da FMVZ/ USP, de 1984 à 2004, foram revisadas histologicamente. A grande maioria dos casos (34%) foi classificada como adenoma moderadamente diferenciado, grupo II, em machos com mais de oito anos de idade o que reflete a dependência androgênica dessas neoplasias. A análise quantitativa da proliferação celular e apoptose nos diferentes tipos histológicos de neoplasias, hiperplasia e tecido normal dessas glândulas determinou um padrão paralelo de aumento de ambas as quantificações. Com os resultados do índice de crescimento ajustado obtivemos que, embora os carcinomas tenham um nível de proliferação celular muito maior que os adenomas (grupo I), esses têm um potencial de crescimento maior, levando-se em conta a apoptose. Investigamos, também, a expressão de Cx43, 26 e 32 nessas glândulas perianais com métodos imunoistoquímicos. A Cx 43 expressava-se em glândulas perianais normais, hiperplásicas, adenomas (grupo I) e adenomas moderadamente diferenciados. Nos adenomas pouco diferenciados (grupo II), a expressão estava reduzida e não se expressava nos carcinomas (grupo III). A Cx 26 acumulava-se no citoplasma nas glândulas normais, hiperplásicas, adenomas (grupo I) e adenomas moderadamente diferenciados (grupo II). Nos adenomas pouco diferenciados (grupo II), a expressão estava reduzida e, ausente, nos carcinomas. A Cx 32 não foi identificada em nenhum dos grupos (I, II e III) ou glândulas normais e hiperplásicas. Concluindo, Cx 43 e Cx26 são importantes para a homeostasia de glândula perianal normal, podendo estar associadas aos receptores de andrógenos presentes em suas células. Este foi o primeiro estudo mostrando a apoptose e sua influência na fase promocional da carcinogênese e, também, o primeiro estudo mostrando a expressão de Cx43, Cx 26 citoplasmática e ausência de expressão da Cx 32 em glândulas perianais normais, hiperplásicas e neoplásicas em cães / Two hundred and forty five neoplasms of the perianal glands of dogs from the archives of the Department of Pathology of the FMVZ/USP, 1984 to 2004, have been reviewed hystologically. Most of the cases (34%) were classified as moderately differentiated adenomas, group II, in males over 8 years of age, which showed an androgenic dependence of these neoplasms. The quantitative analysis of the cellular proliferation and apoptosis, in the different hystologic types of neoplasia, hyperplasia and normal tissue of these glands, determined a parallel pattern of increase in both quantifications. The values of the net growth index showed that although carcinomas have a much higher level of proliferation than adenomas (group I), these latter have a much higher potential of growth, taking into account the effect of the apoptosis. The occurrence of Cx 43, 26 and 32 in these perianal glands was also investigated by immunohystochemical methods. Cx 43 expression was present in normal, hyperplasic, adenomas (group I) and moderately differentiated adenomas perianal glands. In poorly differentiated adenomas (group II), the expression was reduced and was absent in carcinomas. Cx 26 was accumulated in the cytoplasm in normal, hyperplasic, adenomas (group I) and moderately differentiated adenomas glands. In poorly differentiated adenomas (group II), the expression was reduced and was absent in carcinomas. Cx 32 was not found in all groups (I, II, III), normal and hyperplasic glands. In conclusion, Cx 43 and Cx 26 are important for homeostasis of normal canine perianal glands, being able to be associated with the androgen receptors present in their cells. This was the first study showing the apoptosis and its influence on the promotional phase of carcinogenesis and, also, the first study showing the occurrence of Cx 43, cytoplasmatic Cx 26 and no expression of Cx 32 in normal, hyperplasic and neoplastic canine perianal glands
15

THE PHYSIOLOGICAL AND PATHOPHYSIOLOGICAL ROLES OF MELANOTRANSFERRIN

Suryo Rahmanto, Yohan January 2007 (has links)
Doctor of Philosophy(PhD) / Melanotransferrin or melanoma tumour antigen p97 (MTf) is a transferrin homologue that is found predominantly bound to the cell membrane via a glycosylphosphatidylinositol anchor. The molecule is a member of the transferrin super-family that binds iron through a single high affinity iron(III)-binding site. Melanotransferrin was originally identified at high levels in melanoma cells and other tumours, but at lower levels in normal tissues. Since its discovery, the function of MTf has remained intriguing, particularly regarding its role in cancer cell iron transport. In fact, considering the crucial role of iron in many metabolic pathways e.g., DNA and haem synthesis, it is important to understand the function of melanotransferrin in the transport of this vital nutrient. Melanotransferrin has also been implicated in diverse physiological processes, such as plasminogen activation, angiogenesis, cell migration and eosinophil differentiation. Despite these previous findings, the exact biological and molecular function(s) of MTf remain elusive. Therefore, it was important to investigate the function of this molecule in order to clarify its role in biology. To define the roles of MTf, six models were developed during this investigation. These included: the first MTf knockout (MTf -/-) mouse; down-regulation of MTf expression by post-transcriptional gene silencing (PTGS) in SK-Mel-28 and SK-Mel-2 melanoma cells; hyper-expression of MTf expression in SK-N-MC neuroepithelioma cells and LMTK- fibroblasts cells; and a MTf transgenic mouse (MTf Tg) with MTf hyperexpression. The MTf -/- mouse was generated through targeted disruption of the MTf gene. These animals were viable, fertile and developed normally, with no morphological or histological abnormalities. Assessment of Fe indices, tissue Fe levels, haematology and serum chemistry parameters demonstrated no differences between MTf -/- and wild-type (MTf +/+) littermates, suggesting MTf was not essential for Fe metabolism. However, microarray analysis showed differential expression of molecules involved in proliferation such as myocyte enhancer factor 2a (Mef2a), transcription factor 4 (Tcf4), glutaminase (Gls) and apolipoprotein d (Apod) in MTf -/- mice compared with MTf +/+ littermates. Considering the role of MTf in melanoma cells, PTGS was used to down-regulate MTf mRNA and protein levels by >90% and >80%, respectively. This resulted in inhibition of cellular proliferation and migration. As found in MTf -/- mice, melanoma cells with suppressed MTf expression demonstrated up-regulation of MEF2A and TCF4 in comparison with parental cells. Furthermore, injection of melanoma cells with decreased MTf expression into nude mice resulted in a marked reduction of tumour initiation and growth. This strongly suggested a role for MTf in proliferation and tumourigenesis. To further understand the function of MTf, a whole-genome microarray analysis was utilised to examine the gene expression profile of five models of modulated MTf expression. These included two stably transfected MTf hyper-expression models (i.e., SK-N-MC neuroepithelioma and LMTK- fibroblasts) and one cell type with downregulated MTf expression (i.e., SK-Mel-28 melanoma). These findings were then compared with alterations in gene expression identified using the MTf -/- mouse. In addition, the changes identified from the microarray data were also assessed in another model of MTf down-regulation in SK-Mel-2 melanoma cells. In the cell line models, MTf hyper-expression led to increased proliferation, while MTf down-regulation resulted in decreased proliferation. Across all five models of MTf down- and upregulation, three genes were identified as commonly modulated by MTf. These included ATP-binding cassette sub-family B member 5 (Abcb5), whose change in expression mirrored MTf down- or up-regulation. In addition, thiamine triphosphatase (Thtpa) and Tcf4 were inversely expressed relative to MTf levels across all five models. The products of these three genes are involved in membrane transport, thiamine phosphorylation and proliferation/survival, respectively. Hence, this study identifies novel molecular targets directly or indirectly regulated by MTf and the potential pathways involved in its function, including modulation of proliferation. To further understand the function of MTf, transgenic mice bearing the MTf gene under the control of the human ubiquitin-c promoter were generated and characterised. In MTf Tg mice, MTf mRNA and protein levels were hyper-expressed in a variety of tissues compared with control mice. Similar to the MTf -/- mice, these animals exhibited no gross morphological, histological, nor Fe status changes when compared with wild-type littermates. The MTf Tg mice were also born in accordance with classical Mendelian ratios. However, haematological data suggested that hyper-expression of MTf leads to a mild, but significant decrease in erythrocyte count. In conclusion, the investigations described within this thesis clearly demonstrate no essential role for MTf in Fe metabolism both in vitro and in vivo. In addition, this study generates novel in vitro and in vivo models for further investigating MTf function. Significantly, the work presented has identified novel role(s) for MTf in cell proliferation, migration and melanoma tumourigenesis.
16

THE PHYSIOLOGICAL AND PATHOPHYSIOLOGICAL ROLES OF MELANOTRANSFERRIN

Suryo Rahmanto, Yohan January 2007 (has links)
Doctor of Philosophy(PhD) / Melanotransferrin or melanoma tumour antigen p97 (MTf) is a transferrin homologue that is found predominantly bound to the cell membrane via a glycosylphosphatidylinositol anchor. The molecule is a member of the transferrin super-family that binds iron through a single high affinity iron(III)-binding site. Melanotransferrin was originally identified at high levels in melanoma cells and other tumours, but at lower levels in normal tissues. Since its discovery, the function of MTf has remained intriguing, particularly regarding its role in cancer cell iron transport. In fact, considering the crucial role of iron in many metabolic pathways e.g., DNA and haem synthesis, it is important to understand the function of melanotransferrin in the transport of this vital nutrient. Melanotransferrin has also been implicated in diverse physiological processes, such as plasminogen activation, angiogenesis, cell migration and eosinophil differentiation. Despite these previous findings, the exact biological and molecular function(s) of MTf remain elusive. Therefore, it was important to investigate the function of this molecule in order to clarify its role in biology. To define the roles of MTf, six models were developed during this investigation. These included: the first MTf knockout (MTf -/-) mouse; down-regulation of MTf expression by post-transcriptional gene silencing (PTGS) in SK-Mel-28 and SK-Mel-2 melanoma cells; hyper-expression of MTf expression in SK-N-MC neuroepithelioma cells and LMTK- fibroblasts cells; and a MTf transgenic mouse (MTf Tg) with MTf hyperexpression. The MTf -/- mouse was generated through targeted disruption of the MTf gene. These animals were viable, fertile and developed normally, with no morphological or histological abnormalities. Assessment of Fe indices, tissue Fe levels, haematology and serum chemistry parameters demonstrated no differences between MTf -/- and wild-type (MTf +/+) littermates, suggesting MTf was not essential for Fe metabolism. However, microarray analysis showed differential expression of molecules involved in proliferation such as myocyte enhancer factor 2a (Mef2a), transcription factor 4 (Tcf4), glutaminase (Gls) and apolipoprotein d (Apod) in MTf -/- mice compared with MTf +/+ littermates. Considering the role of MTf in melanoma cells, PTGS was used to down-regulate MTf mRNA and protein levels by >90% and >80%, respectively. This resulted in inhibition of cellular proliferation and migration. As found in MTf -/- mice, melanoma cells with suppressed MTf expression demonstrated up-regulation of MEF2A and TCF4 in comparison with parental cells. Furthermore, injection of melanoma cells with decreased MTf expression into nude mice resulted in a marked reduction of tumour initiation and growth. This strongly suggested a role for MTf in proliferation and tumourigenesis. To further understand the function of MTf, a whole-genome microarray analysis was utilised to examine the gene expression profile of five models of modulated MTf expression. These included two stably transfected MTf hyper-expression models (i.e., SK-N-MC neuroepithelioma and LMTK- fibroblasts) and one cell type with downregulated MTf expression (i.e., SK-Mel-28 melanoma). These findings were then compared with alterations in gene expression identified using the MTf -/- mouse. In addition, the changes identified from the microarray data were also assessed in another model of MTf down-regulation in SK-Mel-2 melanoma cells. In the cell line models, MTf hyper-expression led to increased proliferation, while MTf down-regulation resulted in decreased proliferation. Across all five models of MTf down- and upregulation, three genes were identified as commonly modulated by MTf. These included ATP-binding cassette sub-family B member 5 (Abcb5), whose change in expression mirrored MTf down- or up-regulation. In addition, thiamine triphosphatase (Thtpa) and Tcf4 were inversely expressed relative to MTf levels across all five models. The products of these three genes are involved in membrane transport, thiamine phosphorylation and proliferation/survival, respectively. Hence, this study identifies novel molecular targets directly or indirectly regulated by MTf and the potential pathways involved in its function, including modulation of proliferation. To further understand the function of MTf, transgenic mice bearing the MTf gene under the control of the human ubiquitin-c promoter were generated and characterised. In MTf Tg mice, MTf mRNA and protein levels were hyper-expressed in a variety of tissues compared with control mice. Similar to the MTf -/- mice, these animals exhibited no gross morphological, histological, nor Fe status changes when compared with wild-type littermates. The MTf Tg mice were also born in accordance with classical Mendelian ratios. However, haematological data suggested that hyper-expression of MTf leads to a mild, but significant decrease in erythrocyte count. In conclusion, the investigations described within this thesis clearly demonstrate no essential role for MTf in Fe metabolism both in vitro and in vivo. In addition, this study generates novel in vitro and in vivo models for further investigating MTf function. Significantly, the work presented has identified novel role(s) for MTf in cell proliferation, migration and melanoma tumourigenesis.
17

Evolução dos índices de proliferação celular e apoptose em placentas de ratas com diabete grave : relação com glicemia materna e o resultado perinatal /

Costa, Elaine Cristina Nunes Fagundes. January 2002 (has links)
Resumo: Não existem relatos sobre estudo concomitante de proliferação celular e apoptose placentária em ratas com diabete grave que é modelo de RCIU. O objetivo foi definir a técnica para estudar os índices de proliferação celular e de apoptose na placenta de ratas com diabete grave, no 18° e 21° dias de prenhez. Ratas Wistar prenhes constituíram quatro grupos experimentais, de acordo com a presença ou não de diabete, induzido pelo Streptozotocin e da idade de resolução da prenhez no 18º e 21º dias. Foram colhidas as placentas e analisadas a proliferação celular pelo método do PCNA e a apoptose pelos métodos de HE e TUNEL. Os dados foram comparados pelos testes t ou de Mann- Whitney. O índice de proliferação celular foi menor no grupo diabético de 21 dias em relação aos outros grupos, sendo que tanto o HE como o TUNEL detectaram esses índices menores no grupo diabético de 21 dias. A análise da apoptose pelo TUNEL, com índices apresentados por área de tecido placentário, parece ser mais adequada que o HE, pela rapidez na leitura das lâminas e pelos maiores índices observados. Os índices de PCNA e apoptose placentários por campo e por mm2, foram menores nos grupos diabéticos no 21° dia da prenhez. No 18° dia, estas análises foram equivalentes nos grupos controle e diabético; não houve correlação entre os índices de PCNA e apoptose no 18° e no 21° dias, nos grupos controle e diabético. / Abstract: There are no reports of placental studies of cellular proliferation and apoptosis in rats with severe diabetes, that is a IUGR (inter-uterine growth restriction) model. The aim of this study was to define a technique for studying cell proliferation and placental apoptosis of rats with severe diabetes, on the 18th and 21st days of pregnancy. Pregnant Wistar rats were divided into four experimental groups, with and without diabetes, induced by Streptozotocin, and pregnancy time of 18 and 21 days resolution. Placentae were collected and cell proliferation was analyzed by the PCNA method, and apoptosis by HE and TUNEL methods; and the data were compared by t tests or Mann-Whitney. The cell proliferation rate was lower in the diabetic group of 21 days pregnancy, in both HE and TUNEL tests. Analyses of apoptosis by TUNEL technique wich was presented by placental tissue area, seemed to be more adequate than HE, due to quickness on slide reading, and by the higher observed indexes. The indexes of PCNA and placental apoptosis by sight and in mm2 were lower in the diabetic groups on the pregnancy 21st day. On the 18th day, these analyses showed similar values in the control and the diabetic groups; there was no correlation between PCNA and apoptosis indexes on the 18th and on the 21st days, in control and diabetic groups. / Orientador: Marilza Vieira Cunha Rudge / Coorientador: Luís Fernando Barbisan / Doutor
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Cell proliferation rate in clinically healthy oral mucosa of crack cocaine users

Matheus, Paula Daniele January 2012 (has links)
Objetivo: Avaliar a taxa proliferativa de células esfoliadas da mucosa bucal clinicamente saudável de usuários de crack. Material e Métodos: esfregaços orais foram coletados de língua e assoalho bucal de 87 indivíduos, divididos em três grupos: os usuários de crack (CRCO), n = 26; fumantes / etilistas (SA), n = 26 e controles (C ), n = 35. Lâminas histológicas foram submetidas à técnica de impregnação pela prata para quantificação do número de AgNORs/núcleo. As imagens foram obtidas por um sistema de captura de imagem adaptado a um microscópio de luz em x1000 ampliação. A média AgNOR por núcleo (mAgnor) e a percentagem de células com mais de 1,2,3 e 4 AgNORs por núcleo (pAgNOR> 1,> 2> 3 um> 4) foram calculados. Resultados: As células esfoliadas de mucosa da língua SA (3,34 ± 0,51 AgNOR / núcleo) exibiram maior taxa de proliferação celular (p <0,05) quando comparado com C (2,81 ± 0,773 AgNORs / núcleo) e CRCO (2,87 ± 0,51 AgNORs / núcleo) . Um aumento (p <0,05) da mAgnor também foi observada nas células do assoalho bucal (3,55 ± 0,57) em comparação com SA C (3,18 ± 0,53) e CRCO (3,28 ± 0,39). Dados semelhantes foram encontrados usando pAgNOR>1,>2,>3 e > 4. Conclusão: usuários de crack não apresentaram alterações na taxa proliferativa celular da mucosa bucal. Diante dos dados apresentados, o consumo de cigarro, em combinação com o consumo de álcool, continua sendo o maior fator prejudicial à mucosa bucal. / Objective: The aim of this study was to evaluate cell proliferation rate of cells exfoliated from clinically healthy mucosa of crack cocaine users. Material and Methods: Oral smears were collected from tongue and floor of the mouth mucosa of 87 individuals divided into three groups: crack cocaine users (CrCo), n=26; smokers/alcohol drinkers (SA), n=26 and controls (C), n=35. Histological slides were silver-stained using AgNOR technique to evaluate cell proliferation rate. Images were obtained by an image capturing system adapted to a light microscope at x1000 magnification. Quantification considered 50 cells by smear in which the number of AgNOR dots was visually counted. Mean AgNOR numbers per nucleus (mAgNOR) and the percentage of cells with more than 1,2,3 and 4 AgNORs per nucleus (pAgNOR>1,>2>3 an>4) were calculated. Results: Cells exfoliated from tongue mucosa of SA (3.34±0.51 AgNOR/nucleus) exhibit higher cell proliferation rate (p<0.05) when compared to C (2.81±0.773 AgNORs/nucleus) and to CrCo (2.87±0.51 AgNORs/nucleus). An increase (p<0.05) in mAgNOR was also observed in floor of the mouth cells (3.55±0.57) in SA when compared to C (3.18±0.53) and CrCo (3.28±0.39). Similar findings were found using pAgNOR>1,>2,>3 e >4. Conclusion: Crack cocaine users did not present changes in cell proliferation rate of oral mucosa. Between the expositions studied here, cigarette smoking in combination with alcohol consumption remain as the most harmful factors to oral mucosa.
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Avaliação do C-MYC, BCL2, KI67 e índice mitótico como fatores prognósticos em cães com linfoma difuso de grandes células B / Evaluation of C-MYC, BCL2, KI67 and mitotic index as prognostic factors in dogs with diffuse large B cell lymphoma

Sierra Matiz, Oscar Rodrigo [UNESP] 26 February 2016 (has links)
Submitted by osirra@hotmail.com (osirra@hotmail.com) on 2016-04-08T05:35:02Z No. of bitstreams: 1 Sierra_Matiz_Oscar_Ro.pdf: 1664098 bytes, checksum: 33fb78fcc1b1c34c59c528918880411a (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-08T14:59:49Z (GMT) No. of bitstreams: 1 sierramatiz_or_me_jabo.pdf: 1664098 bytes, checksum: 33fb78fcc1b1c34c59c528918880411a (MD5) / Made available in DSpace on 2016-04-08T14:59:49Z (GMT). No. of bitstreams: 1 sierramatiz_or_me_jabo.pdf: 1664098 bytes, checksum: 33fb78fcc1b1c34c59c528918880411a (MD5) Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O linfoma difuso de grandes células B (LDGCB) é o tipo de linfoma mais comum em cães e humanos, caracterizado por seu comportamento agressivo e por promover tempos de sobrevida variáveis, mesmo quando se utiliza a mesma abordagem terapêutica. Atualmente, poucos fatores prognósticos tem sido associados especificamente com LDGCB canino. A imunoexpressão de C-MYC e Bcl2 é reconhecida em humanos como fator prognóstico, devido a relação desses oncogenes com proliferação celular e evasão da apoptose nessa doença. O objetivo desse estudo foi avaliar a imunomarcação dos anticorpos C-MYC, Bcl2, e marcadores de proliferação celular Ki67 e índice mitótico (IM) em cães com LDGCB tratados com protocolo CHOP 19 semanas e correlacioná-la com o tempo de sobrevida e estadiamento clínico visando defini-los como possíveis fatores prognósticos. Trinta amostras de linfonodos de cães diagnosticados com LDGCB foram avaliadas. Para determinar a marcação de C-MYC, Bcl2 e Ki67 foi realizada a técnica de imuno-histoquímica utilizando-se os anticorpos C-MYC, Bcl2 (Santa Cruz Biotechnology) e MIB-1 (Dako), respetivamente. O IM foi calculado como descrito para outras neoplasias. A interpretação dos resultados da imuno-histoquímica para C-MYC e Bcl2, foi calculada no porcentagem de área do número de células marcadas, enquanto a contagem de Ki67 foi realizada com auxílio de uma gratícula, contando-se células positivas por área de 1 cm². Foram estabelecidos pontos de corte, calculando-se a média para todos os marcadores, e posteriormente os valores do C-MYC, Bcl2, Ki67 e a IM foram classificados e definidos como “baixo” ou “alto”. Amostras classificadas como alto C-MYC e alto Bcl2, concomitantemente, foram definidas como alvo duplo MYC/Bcl2. A média de C-MYC foi de 21 (intervalo: 2,5-53,5), de Bcl2 foi de 32,5 (intervalo: 16,9 – 76,8), de Ki67 foi de 107 (intervalo: 1 – 446) e de IM foi de 21 (intervalo: 0-73). Quando comparados os tempos de sobrevida para cada marcador, observou-se que o Ki67 apresentou diferença significativa entre as médias dos grupos baixo (281 dias) e alto (91 dias) (p<0,05). Não houve relação do alvo duplo MYC/Bcl2 com tempos de sobrevida (p>0,05), assim como não houve associação entre a imunomarcação dos anticorpos com o estadiamento clínico. Porém, houve correlação positiva entre C-MYC e Bcl2 (p<0,05) e entre Ki67 e IM (p<0,0001). A expressão imuno-histoquímica dos anticorpos C-MYC e Bcl2, individualmente ou em alvo duplo, não parece constituir um fator prognóstico em cães com LDGCB. Porém, valores acima de 107 células positivas de Ki67 podem estar associados com tempos de sobrevida mais curtos em cães com LDGCB tratados com protocolo CHOP 19 semanas. / Diffuse large B cell lymphoma (DLBCL) is the most common type of lymphoma in dogs and humans, being characterized by its aggressive behavior with variable survival times, even when same therapeutic approach is used. Currently, few prognostic factors are described in the literature regarding canine DLBCL. Immunoexpression of C-MYC and Bcl2 is recognized in humans as a prognostic factor in DLBCL, product of the relationship between these oncogenes with cellular proliferation and apoptosis escape. The objective of this study is to evaluate the immunolabeling of C-MYC, Bcl2, and markers of cellular proliferation Ki67 and mitotic index (MI) in dogs with DLBCL treated with 19 weeks CHOP protocol and correlate them to survival times and clinical stage in order to identify new prognostic factors. Thirty lymphnode samples of dogs diagnosed with DLBCL were evaluated. For immunoexpression of C-MYC, Bcl2 and Ki67, we perform immunohistochemistry using the antibodies C-MYC, Bcl2 (Santa Cruz Biotechnology) and MIB-1 (Dako), respectively. MI was calculated as previously discussed in other tumors. The interpretation of the immunohistochemistry results for C-MYC and Bcl2 was based on the expression level of the area of positive cells, whereas a grid reticle was used for counting Ki67 positive cells in a total area of 1 cm². Cutoff values for all markers were established calculating the mean value and then the C-MYC Bcl2, Ki67 and MI values were classified and defined as “low” and “high”. Cases classified as high C-MYC and high Bcl2, were defined as double target MYC/Bcl2. Mean values were 21 (range: 2,5-53,5) for C-MYC, 32,5 (range: 16,9-76,8) for Bcl2, 107 (range: 1-446) for Ki67 and 21 (range: 0-73) for MI. Only Ki67 immunoexpression was found to be statistical different when survival times were compared between groups low and high (281 days vs 91 days). When double target MYC/Bcl2 was analyzed, no relationship was identified with survival times (p>0,05). Additionally, an association between the antibodies immunoexpression and clinical staging was not identified. However, a positive correlation between C-MYC and Bcl2 (p<0,05) and, Ki67 and MI (P<0,0001) was established. The immunohistochemistry expression of the antibodies C-MYC and Bcl2, individually or in double target, does not appear to constitute a prognostic factor in dogs with DLBCL, whereas a value of Ki67>107 positive cells can be used in dogs with DLBCL to foresee shorter survival times when treated with 19 weeks CHOP protocol.
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Evolução dos índices de proliferação celular e apoptose em placentas de ratas com diabete grave: relação com glicemia materna e o resultado perinatal

Costa, Elaine Cristina Nunes Fagundes [UNESP] January 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2002Bitstream added on 2014-06-13T19:03:50Z : No. of bitstreams: 1 costa_ecnf_dr_botfm.pdf: 894781 bytes, checksum: 2aef88e3eb9258a9238181931845d932 (MD5) / Não existem relatos sobre estudo concomitante de proliferação celular e apoptose placentária em ratas com diabete grave que é modelo de RCIU. O objetivo foi definir a técnica para estudar os índices de proliferação celular e de apoptose na placenta de ratas com diabete grave, no 18° e 21° dias de prenhez. Ratas Wistar prenhes constituíram quatro grupos experimentais, de acordo com a presença ou não de diabete, induzido pelo Streptozotocin e da idade de resolução da prenhez no 18º e 21º dias. Foram colhidas as placentas e analisadas a proliferação celular pelo método do PCNA e a apoptose pelos métodos de HE e TUNEL. Os dados foram comparados pelos testes t ou de Mann- Whitney. O índice de proliferação celular foi menor no grupo diabético de 21 dias em relação aos outros grupos, sendo que tanto o HE como o TUNEL detectaram esses índices menores no grupo diabético de 21 dias. A análise da apoptose pelo TUNEL, com índices apresentados por área de tecido placentário, parece ser mais adequada que o HE, pela rapidez na leitura das lâminas e pelos maiores índices observados. Os índices de PCNA e apoptose placentários por campo e por mm2, foram menores nos grupos diabéticos no 21° dia da prenhez. No 18° dia, estas análises foram equivalentes nos grupos controle e diabético; não houve correlação entre os índices de PCNA e apoptose no 18° e no 21° dias, nos grupos controle e diabético. / There are no reports of placental studies of cellular proliferation and apoptosis in rats with severe diabetes, that is a IUGR (inter-uterine growth restriction) model. The aim of this study was to define a technique for studying cell proliferation and placental apoptosis of rats with severe diabetes, on the 18th and 21st days of pregnancy. Pregnant Wistar rats were divided into four experimental groups, with and without diabetes, induced by Streptozotocin, and pregnancy time of 18 and 21 days resolution. Placentae were collected and cell proliferation was analyzed by the PCNA method, and apoptosis by HE and TUNEL methods; and the data were compared by t tests or Mann-Whitney. The cell proliferation rate was lower in the diabetic group of 21 days pregnancy, in both HE and TUNEL tests. Analyses of apoptosis by TUNEL technique wich was presented by placental tissue area, seemed to be more adequate than HE, due to quickness on slide reading, and by the higher observed indexes. The indexes of PCNA and placental apoptosis by sight and in mm2 were lower in the diabetic groups on the pregnancy 21st day. On the 18th day, these analyses showed similar values in the control and the diabetic groups; there was no correlation between PCNA and apoptosis indexes on the 18th and on the 21st days, in control and diabetic groups.

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