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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.
171

Análise da expressão do fator de crescimento HER-2 e do fator de transcrição FOXO3a  em sarcomas e carcinossarcomas uterinos / Evaluation of the HER-2 growth factor receptor and FOXO3a transcriptional factor in uterine sarcomas and carcinossarcomas

Almeida, Thaís Gomes de 27 October 2015 (has links)
Sarcomas uterinos são tumores mesodérmicos raros que compreendem, aproximadamente, 3% de todos os cânceres uterinos. Até o momento não há consenso quanto os fatores de risco para determinar um pior prognóstico e tratamento mais adequado. A radioterapia adjuvante não tem impacto na sobrevida e o papel da quimioterapia ainda é limitado. Nesse contexto, a busca por marcadores moleculares mostra-se importante tanto para a individualização do tratamento, quanto para o diagnóstico e prognóstico desses tumores. O objetivo deste estudo foi avaliar a expressão de HER-2 e do fator de transcrição FOXO3a nos sarcomas e carcinossarcomas uterinos. Para isso, foram avaliadas 100 amostras incluindo: 56 leiomiossarcomas (LMS), 24 carcinossarcomas (CS), 18 sarcomas do estroma endometrial (SEE) e 2 adenossarcomas (AS). A expressão das proteínas foi avaliada por imunoistoquímica e a presença de alterações no número de cópias do gene HER-2 foi analisada por FISH e SISH. A amplificação de HER-2, resultando na hiperexpressão da proteína, foi observada no componente epitelial de uma única amostra de carcinossarcoma. Não foi observada deleção do gene. Os dados de SISH mostraram maior correlação com os de imunoistoquímica. A expressão de FOXO3a foi significativamente maior em todos os tumores avaliados em comparação ao miométrio, e mostrou associação significativamente com maior sobrevida livre de doença nos casos de LMS. Maior expressão dessa proteína também foi observada nos SEE de alto grau. Mulheres com mais de 50 anos, portadoras de LMS, apresentaram menor expressão de FOXO3a. Em conjunto, os resultados sugerem ser o FOXO3a potencial marcador para o risco de malignização e prognóstico para pacientes com LMS. Além disso, permitem indicar a utilização da técnica de SISH para melhor correlacionar a amplificação de HER-2 com os dados imunoistoquímicos / Uterine sarcomas are rare mesodermal tumors that comprise approximately 3% of all uterine cancers. To date, there is no consensus related to risk factors for poor prognosis and appropriate treatment. Adjuvant radiotherapy has no impact on survival of the patients and chemotherapy has limited role. In this context, the search for molecular markers is important in a search for individualization of treatment, for the diagnosis and prognosis of these tumors. The objective of this study was to evaluate the expression of HER-2 and FOXO3a transcription factor in uterine sarcomas and carcinosarcomas. For this, we evaluated a total of 100 samples including: 56 leiomyosarcomas (LMS), 24 carcinosarcomas (CS), 18 endometrial stromal sarcoma (ESS) and 2 adenosarcomas (AS). The protein expression were assessed by immunohistochemistry and copy number of the HER-2 was performed by FISH and SISH. HER-2 gene amplification, resulting in the protein overexpression was found in the epithelial component of an only one case of carcinosarcoma. SISH data showed higher relationship with protein expression than FISH. FOXO3a expression was significantly higher in all tumors than normal myometrium and it showed association with lower disease free survival, in LMSs patients. Protein overexpression was observed in the high grade SEE samples. LMS women´s with > 50 years old showed lower FOXO3a protein expression. Our results suggest that FOXO3a is involved in leiomyosarcoma risk of malignancy and might become a potential prognostic marker to these patients. Moreover, they allow us to indicate the SISH analysis as a better correlation method with the immunohistochemical data for HER-2 amplification, in the future
172

Análise da expressão do fator de crescimento HER-2 e do fator de transcrição FOXO3a  em sarcomas e carcinossarcomas uterinos / Evaluation of the HER-2 growth factor receptor and FOXO3a transcriptional factor in uterine sarcomas and carcinossarcomas

Thaís Gomes de Almeida 27 October 2015 (has links)
Sarcomas uterinos são tumores mesodérmicos raros que compreendem, aproximadamente, 3% de todos os cânceres uterinos. Até o momento não há consenso quanto os fatores de risco para determinar um pior prognóstico e tratamento mais adequado. A radioterapia adjuvante não tem impacto na sobrevida e o papel da quimioterapia ainda é limitado. Nesse contexto, a busca por marcadores moleculares mostra-se importante tanto para a individualização do tratamento, quanto para o diagnóstico e prognóstico desses tumores. O objetivo deste estudo foi avaliar a expressão de HER-2 e do fator de transcrição FOXO3a nos sarcomas e carcinossarcomas uterinos. Para isso, foram avaliadas 100 amostras incluindo: 56 leiomiossarcomas (LMS), 24 carcinossarcomas (CS), 18 sarcomas do estroma endometrial (SEE) e 2 adenossarcomas (AS). A expressão das proteínas foi avaliada por imunoistoquímica e a presença de alterações no número de cópias do gene HER-2 foi analisada por FISH e SISH. A amplificação de HER-2, resultando na hiperexpressão da proteína, foi observada no componente epitelial de uma única amostra de carcinossarcoma. Não foi observada deleção do gene. Os dados de SISH mostraram maior correlação com os de imunoistoquímica. A expressão de FOXO3a foi significativamente maior em todos os tumores avaliados em comparação ao miométrio, e mostrou associação significativamente com maior sobrevida livre de doença nos casos de LMS. Maior expressão dessa proteína também foi observada nos SEE de alto grau. Mulheres com mais de 50 anos, portadoras de LMS, apresentaram menor expressão de FOXO3a. Em conjunto, os resultados sugerem ser o FOXO3a potencial marcador para o risco de malignização e prognóstico para pacientes com LMS. Além disso, permitem indicar a utilização da técnica de SISH para melhor correlacionar a amplificação de HER-2 com os dados imunoistoquímicos / Uterine sarcomas are rare mesodermal tumors that comprise approximately 3% of all uterine cancers. To date, there is no consensus related to risk factors for poor prognosis and appropriate treatment. Adjuvant radiotherapy has no impact on survival of the patients and chemotherapy has limited role. In this context, the search for molecular markers is important in a search for individualization of treatment, for the diagnosis and prognosis of these tumors. The objective of this study was to evaluate the expression of HER-2 and FOXO3a transcription factor in uterine sarcomas and carcinosarcomas. For this, we evaluated a total of 100 samples including: 56 leiomyosarcomas (LMS), 24 carcinosarcomas (CS), 18 endometrial stromal sarcoma (ESS) and 2 adenosarcomas (AS). The protein expression were assessed by immunohistochemistry and copy number of the HER-2 was performed by FISH and SISH. HER-2 gene amplification, resulting in the protein overexpression was found in the epithelial component of an only one case of carcinosarcoma. SISH data showed higher relationship with protein expression than FISH. FOXO3a expression was significantly higher in all tumors than normal myometrium and it showed association with lower disease free survival, in LMSs patients. Protein overexpression was observed in the high grade SEE samples. LMS women´s with > 50 years old showed lower FOXO3a protein expression. Our results suggest that FOXO3a is involved in leiomyosarcoma risk of malignancy and might become a potential prognostic marker to these patients. Moreover, they allow us to indicate the SISH analysis as a better correlation method with the immunohistochemical data for HER-2 amplification, in the future
173

Caractérisation par cytogénétique moléculaire des chromosomes marqueurs surnuméraires et étude de leur implication dans le développement et la reproduction humaine / Molecular cytogenetic characterization of small supernumerary marker chromosomes and study of their implication in human development and reproductive function

Guediche, Narjes 12 June 2012 (has links)
Les chromosomes marqueurs surnuméraires (CMS) sont définis comme des chromosomes de structure anormale qui ne peuvent pas être identifiés ni caractérisés de façon non ambigüe par les techniques de cytogénétique conventionnelle seules et qui sont de taille égale ou plus petits qu’un chromosome 20 de la même métaphase. La prévalence de cette anomalie chromosomique est estimée à 0,071% en post-natal, 0,075% en diagnostic prénatal et 0,288% chez les patients atteints de retard mental et/ou du développement. Chez les patients infertiles, la fréquence des CMS est estimée à 0,122% et varie selon le sexe. Les CMS sont sans conséquence clinique dans 70% des cas. Dans un tiers des cas, ils peuvent être responsables de nombreuses anomalies du développement et de la reproduction humaine. A ce jour, il existe très peu d’études de caractérisation des CMS permettant une cartographie précise des gènes présents. Dans ce travail, nous avons étudié une série de huit CMS par cytogénétique conventionnelle, FISH (fluorescent in situ hybridization) et CGH array (array comparative genomic hybridization). Nous avons établi une cartographie des gènes présents dans ces CMS. L’étude de la relation génotype-phénotype des patients nous a permis de proposer l’implication de certains gènes candidats dans des anomalies du développement et de la reproduction humaine. Notre étude de l’implication des CMS dans les anomalies du développement humain s’est basée sur l’étude cytogénétique de trois fœtus. Les deux premiers fœtus étaient porteurs d’un CMS(20) en anneau. Le sujet 1 présentait un retard de croissance intra-utérin (RCIU) et une dysmorphie cranio-faciale. Le sujet 2 n’avait pas d’anomalies particulières à part une obésité diagnostiquée à l’âge de quatre mois. La taille de ces CMS(20) était de 13,6 Mb pour le sujet 1 et 4,8 Mb pour le sujet 2. Le gène SSTR4 présent sur le CMS(20) du sujet 2 code pour un récepteur de la somatostatine. Cette hormone joue un rôle dans le comportement alimentaire. Le troisième fœtus présentait un hygroma kystique et un RCIU associé à un CMS(13) néocentromérique. Les explorations par CGH array ont révélé un gain chromosomique de la région 13q21.1qter de 39 Mb contenant 80 gènes dont GPC5, GPC6, SPRY2, EFNB2, SOX1 et DZIP1. La modification d’expression de ces gènes est susceptible d’être responsable du phénotype des sujets étudiés.Notre étude de l’implication des CMS dans les anomalies de la reproduction humaine s’est basée sur l’étude cytogénétique de cinq patients qui présentaient des troubles de la fertilité (anomalies de la spermatogenèse, insuffisance ovarienne prématurée, syndrome des ovaires polykystiques et fausses couches spontanées). Les CMS explorés par CGH array correspondaient aux régions chromosomiques 15q11.2 (3,6 Mb), 21p11.2 (0,266 Mb), 6p11.2q12 (9 Mb) et 20p11.21 (3,3 Mb). Le CMS d’une des patientes ne contenait pas d’euchromatine et une autre patiente était porteuse de deux CMS d’origines chromosomiques différentes. Plusieurs gènes candidats (POTE B, BAGE et THBD) ont pu être identifiés. La modification de leur expression ainsi que des effets mécaniques ou biochimiques perturbant la méiose et la maturation des gamètes pourraient être responsables des troubles de la fertilité observés chez ces patients. L’étude des CMS par CGH array nous a permis de caractériser précisément les points de cassure des CMS, leur taille et leur composition génétique afin de cartographier les gènes présents dans les CMS et d’établir des relations entre le génotype et le phénotype des patients. / Small supernumerary marker chromosomes (sSMC) are defined as structurally abnormal chromosomes which cannot be unambiguously identified or characterized by conventional banding cytogenetic techniques alone and are generally equal in size or smaller than a chromosome 20 of the same metaphase spread. sSMC frequency is estimated at 0.071% in postnatal cases, 0.075% in prenatal cases, and 0.288% for mentally and/or development retarded patients. In infertile patients cases, sSMC frequency is estimated at 0.122% and is different in male (0.165%) and female infertility (0.022%). sSMC have no clinical consequences in 70% of the cases. In one third of the cases, they can be responsible for various human development and reproduction anomalies. To date, only a few studies precisely characterizing the sSMC contents have been performed.In this study, we used conventional cytogenetics, FISH (fluorescent in situ hybridization) and array CGH (array comparative genomic hybridization) to characterize eight sSMC and to precisely localize the genes included. The study of the genotype-phenotype correlations of the patients led us to suppose the implication of some candidate genes in human development and reproduction anomalies.Our study of the implication of sSMC in human development anomalies was based on the cytogenetic study of three fetuses. The first two fetuses carried a ring sSMC(20). Case 1 presented with intrauterine growth retardation and craniofacial dysmorphism. Case 2 had a normal phenotype except for obesity diagnosed at the age of four months. The size of these sSMC(20) was approximately 13,6 Mb for case 1 and 4,8 Mb for case 2. The SSTR4 gene located on the case 2 sSMC(20) is coding for one of the somatostatin receptor. This hormone has multiple effects on variable cells and is implicated in the regulation of food behavior, which could explain the obesity of case 2. Case 3 presented with intrauterine growth retardation and a cystic hygroma associated with a neocentric sSMC(13). Array CGH investigations showed a 32.9 Mb gain from 13q31.1 to 13qter region containing 80 genes. Among these genes, six genes could be involved in the phenotype of the proband (GPC5, GPC6, SPRY2, EFNB2, SOX1 and DZIP1). The expression modification of these genes could be responsible for the phenotype observed.Our study of the implication of sSMC in human reproduction anomalies was based on the cytogenetic study of five patients presenting fertility troubles (spermatogenesis impairment, ovarian insufficiency, polycystic ovary syndrome and repeated abortions). The sSMC explored by array CGH corresponded to the 15q11.2 region (3.6 Mb), the 21p11.2 region (0.266 Mb), the 6p11.2q12 region (9 Mb) and 20p11.21 region (3.3 Mb). The sSMC of one of the patients did not contain euchromatin and one patient carried two sSMC derived from two different chromosomes. Among the genes present on the sSMC, some candidate genes (POTE B, BAGE and THBD) have been identified. The modification of their expression and mechanical or biochemical effects of the sSMC impeding meiosis could be directly responsible for the fertility trouble observed in these patients. A detailed molecular cytogenetic investigation using array CGH allowed us to precisely characterize the chromosomal breakpoints, the size and genomic constitution of sSMC. This study may be helpful to address genotype–phenotype correlations and for medical and genetic counseling.
174

Citogenética de 13 espécies de aranhas haploginas pertencentes às famílias Pholcidae, Sicariidae e Scytodidae (Araneomorphae): evolução cromossômica, sistema cromossômico de determinação sexual e citotaxonomia

Araujo, Douglas de [UNESP] 27 April 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04-27Bitstream added on 2014-06-13T21:01:36Z : No. of bitstreams: 1 araujo_d_dr_rcla.pdf: 1858376 bytes, checksum: dbeb43d42be45d0e0d9524437faa5d74 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dentre todas as ordens de aracnideos conhecidas taxonomicamente, Araneae e a segunda mais diversa, com numero de especies menor somente em relacao a Acari. Atualmente, 39.725 especies ja foram descritas, sendo que centenas de novas descricoes sao feitas a cada ano em diversas familias de aranhas. O conhecimento citogenetico sobre a ordem restringe-se a analise de 638 especies (ca 2%) do total descrito do ponto de vista taxonomico. Este trabalho tem como objetivos fornecer uma compilacao dos dados citogeneticos existentes para a ordem na literatura ate a presente data, bem como caracterizar e estabelecer as estrategias de diferenciacao cromossomica em 13 especies de aranhas pertencentes ao grupo das haploginas, clado que corresponde a somente 3.257 especies (ca 8%) do total da ordem e a apenas 41 especies (ca 6%) do total cariotipado ate os dias atuais. Aliado a baixa representatividade dos dados cariologicos, outros pontos que fazem das haploginas um grupo interessante para estudos sao a predominancia de cromossomos meta/submetacentricos e de sistemas cromossomicos de determinacao sexual simples e multiplos, muitas vezes incluindo um cromossomo Y, ambas caracteristicas raras entre os outros clados de Araneae. As especies analisadas pertencem a tres familias de haploginas, Pholcidae (Mesabolivar luteus e Micropholcus fauroti), Sicariidae (Loxosceles amazonica, Loxosceles gaucho, Loxosceles hirsuta, Loxosceles intermedia, Loxosceles laeta, Loxosceles puortoi, Loxosceles similis e Sicarius tropicus) e Scytodidae (Scytodes fusca, Scytodes globula e Scytodes itapevi). Em Pholcidae, os resultados ineditos para os dois generos mostraram... / Mesabolivar luteus (Keyserling 1891) and Micropholcus fauroti (Simon 1887) specimens were collected in Ubatuba and Rio Claro, both in the state of São Paulo, Brazil. Mesabolivar luteus showed 2n(.) = 15 = 14 + X and 2n(.) = 16 = 14 + XX in mitotic metaphases and 7II + X in diplotenic cells. During late prophase I, all bivalents presented a ring shape, evidencing two chiasmata per bivalent. In this species, some diplotenic cells appear in pairs, maybe due to specific characteristics of the intercellular bridges. The metaphases II showed n = 7 or n = 8 = 7 + X chromosomes. Micropholcus fauroti evidenced 2n(.) = 17 = 16 + X in spermatogonial metaphases and 8II+X in diplotenic cells, with only one chiasma per bivalent, contrasting with M. luteus. In both species, all chromosomes were metacentrics. The X sexual chromosome was the largest element and appeared as a univalent during meiosis I. These are the first cytogenetical data for the genera Mesabolivar and Micropholcus. Additionally, M. luteus is the first chromosomally analyzed species of the New World clade and the observed diploid number for M. fauroti had not yet been recorded in Pholcidae.
175

Avaliação de gametas e embriões bovinos produzidos in vitro após exposição experimental ao BoHV-5 /

Frade, Camila da Silva. January 2009 (has links)
Resumo: A produção in vitro (PIV) de embriões e a transferência de embriões (TE) tratam-se de biotecnologias da reprodução, as quais são rotineiramente aplicadas no melhoramento genético da espécie bovina. No entanto, resta determinar até que ponto sua utilização implica na disseminação de patógenos no rebanho. A fim de elucidar a possibilidade de transmissão do BoHV-5 através de células germinativas e/ou embriões, após exposição experimental in vitro, uma série de 3 experimentos foram realizados. Estes consistiram na exposição de oócitos, espermatozóides e embriões bovinos ao BoHV-5, tendo como critério de avaliação o desenvolvimento embrionário, bem como a detecção do vírus através de emprego da técnica de hibridização in situ (ISH) e PCR, além da apoptose, determinada pelo teste de TUNEL e pela imunomarcação dos fatores pro-apoptóticos (anexina-V, caspase-2 e -3) e antiapoptóticos (BCl-2). O experimento I foi realizado durante o período de maturação oocitária, sendo dividido em I (controle + 10% SFB), II (vírus + 10% SFB; BoHV-SFB) e III (vírus + 1 mg/mL PVA; BoHV-PVA); o experimento II foi realizado na etapa de fertilização, sendo dividido em I (controle) e II (exposto; BoHV-SPTZ); e o experimento III foi feito no período de cultura embrionária, sendo dividido em I (controle) e II (exposto; BoHV-PZ). A análise estatística para os resultados de desenvolvimento embrionário será feita pela ANOVA e teste-t de Bonferroni para os dados dos oócitos infectados e pelo teste t não pareado para os resultados de espermatozóides e embriões infectados, já para a análise da apoptose e marcadores apoptóticos será empregado o teste de Kruskal-Wallis e Dunn, diferenças serão consideradas significativas quando p<0,05. / Abstract: The in vitro production (IVP) of embryos and embryo transfer (ET) are reproduction biotechnologies, which are routinely applied in breeding bovine. However, it remains to determine if these techniques can promote spread of pathogens in the herd. In order to elucidate the possibility of transmission of BoHV-5 by germ cells and/or embryos after in vitro experimental exposure, a total of 3 experiments were performed. These consisted of exposure of oocytes, sperm and embryos to BoHV-5, with the evaluation embryonic development, and detection of the virus through use of the technique of in situ hybridization (ISH) and PCR, in addition to apoptosis, determined by TUNEL test and by immunostaining of the factors pro-apoptotic (annexin-V, caspase-2 and -3) and anti-apoptotic (Bcl-2). The first experiment was conducted during the period of oocyte maturation and was divided into I (control + 10% FBS), II (virus + 10% fetal calf serum; BoHV-SFB) and III (virus + 1 mg / ml PVA, BoHV-PVA ), the second trial was conducted at the stage of fertilization, was divided into I (control) and II (exposure, BoHV-SPTZ), and experiment III was done during the growing stage, and divided into I (control) and II (exposure; BoHV-PZ). Statistical analysis for the results of embryo development will be made by ANOVA and Bonferroni-t test to the data from exposed oocytes and the unpaired t test for the results of sperm and embryos exposed, as for the analysis of apoptosis will be used the Kruskal-Wallis and Dunn, differences are considered significant when p <0.05. / Orientadora: Tereza Cristina Cardoso / Coorientador: Alicio Martins Júnior / Banca: José Fernando Garcia / Banca: Magali D'Angelo / Mestre
176

Linfoma de Burkitt: características clinicopatológicas, imunoistoquímicas e associação com o vírus de Epstein-Barr (EBV) em populações adulta e pediátrica em diferentes regiões geográficas no Brasil / Burkitt lymphoma: clinicopathologic, immunohistochemical and association with Epstein-Barr virus (EBV) in adult and pediatric population in different geographical regions of Brazil

Eduardo Moreira de Queiroga 13 December 2008 (has links)
O linfoma de Burkitt (LB) é neoplasia linfóide de células B de alto grau que apresenta translocação constante envolvendo o proto-oncogene C-MYC. A associação com o vírus de Epstein-Barr (EBV) varia de acordo com a forma clinicopatológica. O presente estudo tem por objetivo analisar as características clinicopatológicas, imunoistoquímicas, incluindo a expressão do fator de transcrição MUM1/IRF4 e das proteínas p53 e p63, e investigar a associação com infecção pelo Herpesvírus humano 8 (HHV-8) e EBV, através de hibridização in situ e PCR, em 234 casos bem caracterizados de LB no Brasil, provenientes das 5 regiões geográficas em pacientes pediátricos e adultos, incluindo casos associados ao HIV. As características clínicas do LB no Brasil, de maneira geral, foram semelhantes às observadas na forma esporádica do LB ocorrendo nos países desenvolvidos. A infecção pelo EBV foi observada em 52,5% dos casos. A maior associação com EBV foi verificada nas regiões Norte e Nordeste e a menor na região Sul. Através de PCR, demonstrou-se predomínio de EBV do tipo A, sendo exceção a região Centro-Oeste. O fator de transcrição MUM1/IRF4 foi expresso em 39,2% dos tumores e apresentou correlação inversa com infecção pelo EBV. A expressão das proteínas p53 e p63 foi observada em 16,2% e 3,8% dos casos, respectivamente. Não se identificou infecção pelo HHV-8. O LB no Brasil apresenta características clinicopatológicas variáveis entre as regiões geográficas. A associação com infecção pelo EBV é intermediária entre a forma endêmica de LB e a forma esporádica ocorrendo em países desenvolvidos, sendo maior em regiões com indicadores sociais menos favoráveis. / Burkitt lymphoma (BL) is a high grade B cell lymphoma with a consistent translocation involving the proto-oncogene C-MYC. The association with the Epstein-Barr virus (EBV) varies depending on the clinicopathological form. This study aims to analyze the clinicopathologic, immunohistochemical features, including the expression of transcription factor MUM1/IRF4 and p53 and p63 proteins, and investigate the association with infection by human herpesvirus-8 (HHV-8) and EBV, by in situ hybridization and PCR, in 234 well-characterized cases of BL in Brazil from the 5 different geographic regions, in adult and pediatric patients, including HIV associated cases. The clinical characteristics of BL in Brazil, in general, were similar to those observed in the sporadic form of BL occurring in developed countries. EBV infection was seen in 52.5% of cases. The strongest association with EBV was found in the North and Northeast and the lowest in the South. PCR study demonstrated predominance of EBV type A, except in the Central-West region. The transcription factor MUM1/IRF4 was expressed in 39.2% of the tumors and showed inverse correlation with EBV infection. The expression of p53 and p63 proteins was observed in 16.2% and 3.8% of cases, respectively. No evidence of HHV-8 infection was found. The BL in Brazil is clinicopathologic diverse and regionally distinct. The association with EBV infection is intermediate between the endemic form of BL and sporadic form occurring in developed countries and is higher in regions with the less favorable social indicators
177

Estudo da expressão dos genes HOXB13 e HHEX em carcinomas epidermóides de boca através das técnicas de RT-PCR e Hibridização in situ. / HOXB13 and HHEX expression study in oral squamous cell carcinoma with the RT-PCR and in situ Hybridization techniques.

Claudia Cazal 13 December 2004 (has links)
O presente estudo teve o objetivo de verificar o padrão de expressão dos genes HOXB13 e HHEX em carcinomas epidermóides de boca (CEB) através das técnicas de Transcriptase Reversa em Reação de Cadeia Polimerase (RT- PCR) e Hibridização In situ (ISH). Fragmentos de tecido tumoral e de tecido não tumoral adjacente à lesão foram obtidos de 30 pacientes portadores de CEB no Serviço de Cirurgia de Cabeça e Pescoço do HC - FMUSP. As amostras tiveram seus cDNAs extraí dos e submetidos à amplificação por PCR. Os “ amplicons” foram visualizados sob luz UV por eletroforese em gel de agarose a 1% contendo brometo de etí dio. A amplificação dos genes foram correlacionadas com a classificação UICC, TNM, graduação histológica, localização e espessura tumoral, invasão de tecidos adjacentes, perineural e vascular. Após seqüenciamento dos “ amplicons” e confirmação dos genes foram confecionadas as sondas de mRNA para realização da técnica de hibridização in situ. Os resultados obtidos através da técnica de RT-PCR mostraram que: a amplificação dos transcritos dos genes HOXB13 e HHEX podem ser detectados tanto no carcinoma epidermóide quanto no tecido não tumoral adjacente à lesão; não existindo diferença na amplificação dos transcritos de ambos genes para os dois grupos de tecido estudados; a amplificação do transcrito do gene HOXB13 mostrou relação estatí stica com os fatores prognósticos: espessura tumoral, invasão perineural e invasão vascular; a amplificação do transcrito do gene HHEX mostrou relação estatí stica com os fatores prognósticos: invasão vascular,envolvimento com os tecidos adjacentes e uma relação inversa com a idade do paciente. A expressão dos transcritos dos genes HOXB13 e HHEX, detectados pela técnica de ISH, mostrou um padrão de marcação consistente e invariável para os tecidos analisados, estando expressos tanto em carcinoma epidermóide quanto no tecido não tumoral adjacentes à lesão. Os resultados apontam para uma correlação entre a expressão do HHEX e do HOXB13 e alguns fatores prognósticos importantes podendo representar um indicador prognóstico valoroso para o entendimento do comportamento biológico do CEB. / The aim of this study was to verify the HOXB13 and HHEX genes expression in oral squamous cell carcinoma (OSCC) using Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) and in situ Hybridization techniques. Tumoral tissues and adjacent non-tumoral oral mucosa specimens were obtained from 30 patients with OSCC at the Head and Neck Surgery Service HC (FMUSP). The samples were cDNA extracted and submitted to the RT-PCR technique. The amplicons were visualized in electrophoresis on a 1% agarose gel with ethidium bromide. Genes expressions were correlated with UICC staging, TNM stage, tumor location, tumor thickness, adjacent tissues involvement, vascular and perineural invasion, and cellular differentiation. Finally, direct sequence analysis was performed on PCR products to confirm cDNA sequence. Riboprobes were confectioned for in situ hybridization analysis. RT-PCR results showed HOXB13 and HHEX transcripts in both tumoral and non-tumoral tissue samples; no statistical correlation was verified between HOXB13/HHEX expressions and tumoral or non-tumoral tissues; there was a positive correlation between HOXB13 tumoral expression and tumor thickness, neural invasion, and vascular invasion; there was a positive correlation between HHEX tumoral expression and adjacent tissue involvement, vascular invasion, and a inverse relationship with patients age; ISH technique exhibited a consistent and invariable pattern of expression for both genes on both tumoral and non-tumoral tissue samples. Present results points out to a correlation between HOXB13 and HHEX expressions, and some important prognostic indicators, and this may represent a valuable tool to understand the biological behavior of OSCC.
178

Estudo da expressão dos genes HOXB13 e HHEX em carcinomas epidermóides de boca através das técnicas de RT-PCR e Hibridização in situ. / HOXB13 and HHEX expression study in oral squamous cell carcinoma with the RT-PCR and in situ Hybridization techniques.

Cazal, Claudia 13 December 2004 (has links)
O presente estudo teve o objetivo de verificar o padrão de expressão dos genes HOXB13 e HHEX em carcinomas epidermóides de boca (CEB) através das técnicas de Transcriptase Reversa em Reação de Cadeia Polimerase (RT- PCR) e Hibridização In situ (ISH). Fragmentos de tecido tumoral e de tecido não tumoral adjacente à lesão foram obtidos de 30 pacientes portadores de CEB no Serviço de Cirurgia de Cabeça e Pescoço do HC - FMUSP. As amostras tiveram seus cDNAs extraí dos e submetidos à amplificação por PCR. Os “ amplicons" foram visualizados sob luz UV por eletroforese em gel de agarose a 1% contendo brometo de etí dio. A amplificação dos genes foram correlacionadas com a classificação UICC, TNM, graduação histológica, localização e espessura tumoral, invasão de tecidos adjacentes, perineural e vascular. Após seqüenciamento dos “ amplicons" e confirmação dos genes foram confecionadas as sondas de mRNA para realização da técnica de hibridização in situ. Os resultados obtidos através da técnica de RT-PCR mostraram que: a amplificação dos transcritos dos genes HOXB13 e HHEX podem ser detectados tanto no carcinoma epidermóide quanto no tecido não tumoral adjacente à lesão; não existindo diferença na amplificação dos transcritos de ambos genes para os dois grupos de tecido estudados; a amplificação do transcrito do gene HOXB13 mostrou relação estatí stica com os fatores prognósticos: espessura tumoral, invasão perineural e invasão vascular; a amplificação do transcrito do gene HHEX mostrou relação estatí stica com os fatores prognósticos: invasão vascular,envolvimento com os tecidos adjacentes e uma relação inversa com a idade do paciente. A expressão dos transcritos dos genes HOXB13 e HHEX, detectados pela técnica de ISH, mostrou um padrão de marcação consistente e invariável para os tecidos analisados, estando expressos tanto em carcinoma epidermóide quanto no tecido não tumoral adjacentes à lesão. Os resultados apontam para uma correlação entre a expressão do HHEX e do HOXB13 e alguns fatores prognósticos importantes podendo representar um indicador prognóstico valoroso para o entendimento do comportamento biológico do CEB. / The aim of this study was to verify the HOXB13 and HHEX genes expression in oral squamous cell carcinoma (OSCC) using Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) and in situ Hybridization techniques. Tumoral tissues and adjacent non-tumoral oral mucosa specimens were obtained from 30 patients with OSCC at the Head and Neck Surgery Service HC (FMUSP). The samples were cDNA extracted and submitted to the RT-PCR technique. The amplicons were visualized in electrophoresis on a 1% agarose gel with ethidium bromide. Genes expressions were correlated with UICC staging, TNM stage, tumor location, tumor thickness, adjacent tissues involvement, vascular and perineural invasion, and cellular differentiation. Finally, direct sequence analysis was performed on PCR products to confirm cDNA sequence. Riboprobes were confectioned for in situ hybridization analysis. RT-PCR results showed HOXB13 and HHEX transcripts in both tumoral and non-tumoral tissue samples; no statistical correlation was verified between HOXB13/HHEX expressions and tumoral or non-tumoral tissues; there was a positive correlation between HOXB13 tumoral expression and tumor thickness, neural invasion, and vascular invasion; there was a positive correlation between HHEX tumoral expression and adjacent tissue involvement, vascular invasion, and a inverse relationship with patients age; ISH technique exhibited a consistent and invariable pattern of expression for both genes on both tumoral and non-tumoral tissue samples. Present results points out to a correlation between HOXB13 and HHEX expressions, and some important prognostic indicators, and this may represent a valuable tool to understand the biological behavior of OSCC.
179

Telomere analysis of normal and neoplastic hematopoietic cells : studies focusing on fluorescence in situ hybridization and flow cytometry

Hultdin, Magnus January 2003 (has links)
<p>The telomeres are specialized structures at the end of the chromosomes composed of the repeated DNA sequence (TTAGGG)n and specific proteins bound to the DNA. The telomeres protect the chromosomes from degradation and end to end fusions. Due to the end-replication problem, the telomeric DNA shortens every cell division, forcing the cells into senescence at a critical telomere length. This process can be counteracted by activating a specialized enzyme, telomerase, which adds telomeric repeats to the chromosome ends leading to an extended or infinite cellular life span. Telomerase activity is absent in most somatic tissues but is found in germ cells, stem cells, activated lymphocytes and the vast majority of tumor cells and permanent cell lines. Hence, telomerase has been suggested as a target for cancer treatment as malignant cells almost exclusively express the enzyme and in that context telomere length measurements will be of great importance.</p><p>Telomere length is traditionally measured with a Southern blot based technique. A new method for telomere analysis of cells in suspension, called flow-FISH, was developed based on fluorescence in situ hybridization using a telomeric peptide nucleic acid (PNA) probe,</p><p>DNA staining with propidium iodide and quantification by flow cytometry. Flow-FISH had high reproducibility and the telomere length measurements showed good correlation with Southern blotting results. The flow-FISH technique also allows studies of cells in specific phases of the cell cycle and the replication timing of telomeric, centromeric and other repetitive sequences were analyzed in a number of cells. Like previous studies, centromeres were shown to replicate late in S phase while the telomere repeats were found to replicate early in S phase or concomitant with the bulk DNA, which is opposite to the patterns described in yeast.</p><p>In benign immunopurified lymphocytes from tonsils, high telomerase activity was found in germinal center (GC) B cells. This population also had high hTERT mRNA levels and displayed a telomere elongation as shown by flow-FISH and Southern blotting. Combined immunophenotyping and flow-FISH on unpurified tonsil cells confirmed the results.</p><p>Chronic lymphocytic leukemia (CLL), the most common leukemia in adults, can be divided into pre-GC CLL, characterized by unmutated immunoglobulin VH genes and worse prognosis, and post-GC CLL, with mutated VH genes and better prognosis. In 61 cases of CLL, telomere length was measured with Southern blotting and VH gene mutation status was analyzed. A new association was found between VH mutation status and telomere length, where cases with longer telomeres and mutated VH genes (post-GC CLL) had better prognosis</p><p>than CLL with short telomeres and unmutated VH genes (pre-GC CLL). A larger study of 112 CLL cases was performed using flow-FISH. The same correlation between telomere length and VH mutation status was found but gender seemed to be of importance as telomere length was a significant prognostic factor for the male CLL patients but not in the female group. Age of the patients and spread of disease seemed to affect the prognostic value of VH gene mutation status.</p>
180

Neuropeptide Y Receptors in Human, Guinea pig and Chicken : Cloning, <i>in vitro</i> Pharmacology and <i>in situ</i> Hybridization

Holmberg, Sara January 2001 (has links)
<p>Neuropeptide Y (NPY) is known to influence a vast number of physiological and behavioral processes such as vasoconstriction, circadian rhythms, feeding, anxiety and memory. Peptides of the NPY family bind to five different cloned G-protein coupled receptor subtypes (Y1, 2, 4-6). The studies compiled in this thesis present inter-species comparisons of sequence similarities, binding properties and expression patterns among receptors of the NPY family.</p><p>Cloning of Y1 and Y2 receptor subtypes from guinea pigs revealed strong binding profile similarity to the corresponding human receptors. Previously demonstrated atypical binding profiles in the caval vein of guinea pigs were concluded to result from other receptors than the cloned Y1 and Y2 receptors, or possibly combinations of distinct receptor subtypes.</p><p>The guinea pig Y5 receptor was found to be expressed in regions of the brain that have been indicated as important for regulation of food intake. Expression in the hypothalamus, amygdala and brain stem was noticed, similar to studies in rats and humans. In other brain regions, such as the striatum and hippocampus, some species differences were observed.</p><p>Mutagenesis studies of the human Y1 receptor indicated sites important for binding both of endogenous agonists and synthetic antagonists. Putative new sites of interaction with the Y1 antagonists BIBP3226 and/or SR120819A were recognized. The data were used to construct a three-dimensional structure model, based on a high-resolution bovine rhodopsin model.</p><p>Cloning of the chicken (<i>Gallus gallus</i>) Y1, Y2 and Y5 receptors revealed high sequence similarities with mammalian receptors. Most endogenous ligands bound with similar affinities as to mammalian receptors. The strongest exception was the discovery of high-affinity binding to chicken Y2 of [Leu<sup>31</sup>, Pro<sup>34</sup>]NPY, which was previously considered to bind non-Y2 receptors only. </p><p>The new human Y1 receptor model provides a basis for further investigations of ligand-receptor interactions which will be aided by information on NPY receptors from other taxa. Guinea pigs are concluded to be a good complement to rats and mice for studying NPY signaling. These results demonstrate the benefits of species comparisons for pharmacological studies.</p>

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