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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.
291

Antitumor activities of tremella aurantialba polysaccharides.

January 2002 (has links)
Choi Pui-yu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 113-123). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (Chinese Version) --- p.iii / Acknowledgements --- p.v / List of Abbreviations --- p.vi / Table of Contents --- p.viii / List of Tables --- p.xii / List of Figures --- p.xiii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Literature Review / Chapter 2.1 --- Mushroom Polysaccharides with Antitumor Activities --- p.7 / Chapter 2.1.1 --- Antitumor β-Glucans --- p.7 / Chapter 2.1.2 --- Antitumor Heteroglycans --- p.9 / Chapter 2.1.3 --- Antitumor Polysaccharide-Protein Complexes --- p.12 / Chapter 2.2 --- Antitumor Activities and Structural Characteristics of Mushroom Polysaccharides --- p.15 / Chapter 2.3 --- Antitumor Effects of Mushroom Polysaccharides In Vitro --- p.19 / Chapter 2.4 --- Antitumor Effects of Mushroom Polysaccharides In Vivo --- p.21 / Chapter 2.5 --- Immunomodulatory Activities --- p.24 / Chapter 2.6 --- Activation of Cytokines by Mushroom Polysaccharides --- p.28 / Chapter 2.7 --- Induction of Nitric Oxide Synthase by Mushroom Polysaccharides --- p.32 / Chapter 2.8 --- Tremella aurantialba --- p.34 / Chapter Chapter 3 --- Materials and Methods --- p.35 / Chapter 3.1 --- Extraction --- p.35 / Chapter 3.1.1 --- Extraction of Crude Tremella aurantialba Polysaccharide --- p.35 / Chapter 3.1.2 --- Fractionation --- p.38 / Chapter 3.1.3 --- Polysaccharide and Protein Content Determination --- p.38 / Chapter 3.1.3.1 --- Phenol-Sulfuric Assay --- p.39 / Chapter 3.1.3.2 --- Lowry-Folin Method --- p.39 / Chapter 3.1.4 --- Gas Chromatography (GC) --- p.40 / Chapter 3.1.5 --- Modified Carbazole Assay --- p.41 / Chapter 3.1.6 --- High Performance Liquid Chromatography (HPLC) --- p.42 / Chapter 3.2 --- In Vitro Studies --- p.43 / Chapter 3.2.1 --- Maintenance of Cell Lines --- p.43 / Chapter 3.2.2 --- Effect on Cancer Cell Lines --- p.43 / Chapter 3.2.2.1 --- Trypan Blue Exclusion Methods --- p.44 / Chapter 3.2.2.2 --- MTT Assay --- p.44 / Chapter 3.2.3 --- Effect on Normal Cell Line --- p.45 / Chapter 3.2.4 --- Coulter Counter --- p.46 / Chapter 3.3 --- In Vivo Studies --- p.47 / Chapter 3.3.1 --- Animals --- p.47 / Chapter 3.3.2 --- Maintenance of Sarcoma 180 Cell Line --- p.47 / Chapter 3.3.3 --- Effect of TAP Fractions on Sarcoma 18 Solid Tumor --- p.48 / Chapter 3.3.3.1 --- Injection of TAP Fractions 24 h After Transplantation --- p.48 / Chapter 3.3.3.2 --- Injection of TAP Fractions 72 h After Transplantation --- p.49 / Chapter 3.4 --- Effect of TAP Fractions on Modulating mRNA Expression of Cytokines and Nitric Oxide Synthase --- p.51 / Chapter 3.4.1 --- Treatment of Mice --- p.51 / Chapter 3.4.2 --- Isolation of Splenocytes and Peritoneal Exduate Cells --- p.51 / Chapter 3.4.3 --- Extraction of Total mRNA from Splenocyte and Peritoneal Exduate Cells --- p.52 / Chapter 3.4.4 --- Reverse Transcription-Polymerase Chain Reaction (RT-PCR) --- p.53 / Chapter 3.4.4.1 --- Reverse Transcription --- p.53 / Chapter 3.4.4.2 --- Polymerase Chain Reaction --- p.56 / Chapter 3.4.5 --- DNA Sequencing --- p.57 / Chapter 3.5 --- Statistical Analysis --- p.58 / Chapter Chapter 4 --- Results --- p.59 / Chapter 4.1 --- Isolation and Characterization of TAP Fractions --- p.59 / Chapter 4.1.1 --- Percentage Yield of TAP Fractions --- p.59 / Chapter 4.1.2 --- Polysaccharide and Protein Content of TAP Fractions --- p.59 / Chapter 4.1.3 --- Relative Monosaccharide Contents in TAP Fractions --- p.60 / Chapter 4.1.4 --- Results of HPLC --- p.60 / Chapter 4.2 --- Effects of TAP Fractions In Vitro --- p.69 / Chapter 4.2.1 --- Effects of TAP Fractions on Suspension Cancer Cell Lines --- p.69 / Chapter 4.2.2 --- Effects of TAP Fractions on Adhesion Cancer Cell Lines --- p.69 / Chapter 4.2.3 --- Effects of TAP Fractions on Normal Cell Line --- p.70 / Chapter 4.2.4 --- Effect of TAP 2 on HL-60 Cell Line as Evaluated by Coulter Counter --- p.70 / Chapter 4.3 --- Antitumor Effect of TAP Fractions In Vivo --- p.78 / Chapter 4.4 --- Effect of TAP Fractions on Modulating mRNA Expressions of Cytokines and Nitric Oxide Sythase (NOS) --- p.83 / Chapter 4.4.1 --- Results of RT-PCR --- p.83 / Chapter 4.4.2 --- Sequencing --- p.84 / Chapter Chapter 5 --- Discussion --- p.91 / Chapter 5.1 --- Characterization of TAP Fractions --- p.91 / Chapter 5.2 --- Antitumor Effects of TAP Fractions In Vitro --- p.96 / Chapter 5.3 --- Furhter Study --- p.109 / Chapter Chapter 6 --- Conclusion --- p.111 / References --- p.113
292

Antitumor activities of polysaccharides from the long-veiled lady mushroom Dictyophora indusiata.

January 2002 (has links)
Poon Shuk-ching. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 113-125). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Abstract (Chinese Version) --- p.iv / Table of Contents --- p.vi / List of Tables --- p.x / List of Figures --- p.xi / List of Abbreviations --- p.xiii / Chapter Chapterl 1 --- ntroduction --- p.1 / Chapter Chapter 2 --- Literature Review --- p.5 / Chapter 2.1 --- Mushroom Polysaccharides From Basidiomycetes --- p.5 / Chapter 2.1.1 --- Antitumor and Immunomodulatory Activity --- p.6 / Chapter 2.1.2 --- Antiviral Activity --- p.9 / Chapter 2.1.3 --- Hypoglycermic Activity --- p.11 / Chapter 2.1.4 --- Free Radical Scavenging Activity --- p.11 / Chapter 2.2 --- Mushroom Dictyophora indusiata --- p.13 / Chapter 2.2.1 --- Nutritional Value --- p.13 / Chapter 2.2.2 --- Structural Characteristic of Dictyophora indusiata Polysaccharides --- p.14 / Chapter 2.2.3 --- Biological Activity --- p.16 / Chapter 2.3 --- In vivo Antitumor Study --- p.19 / Chapter 2.4 --- Induction of Cytokines Production in Immune System --- p.21 / Chapter 2.5 --- In vitro Antitumor Study --- p.25 / Chapter 2.6 --- Cell Cycle Regulation --- p.28 / Chapter Chapter 3 --- Materials & Methods --- p.34 / Chapter 3.1 --- Extraction --- p.34 / Chapter 3.1.1 --- Extraction of Dictyophora indusiata Polysaccharides --- p.34 / Chapter 3.1.2 --- Purification of Dictyophora indusiata Polysaccharides --- p.35 / Chapter 3.1.2.1 --- Preparation of DEAE-cellulose Ion Exchanger --- p.35 / Chapter 3.1.2.2 --- Fractionation --- p.35 / Chapter 3.2. --- Characterization of Dictyophora indusiata Polysaccharides --- p.39 / Chapter 3.2.1 --- Polysaccharide Content Determination --- p.39 / Chapter 3.2.2 --- Protein Content Determination --- p.39 / Chapter 3.2.3 --- Gas Chromatography (GC) --- p.40 / Chapter 3.2.4 --- Uronic Acid Content Determination --- p.42 / Chapter 3.2.5 --- High Performance Liquid Chromatography (HPLC) --- p.43 / Chapter 3.3 --- In vivo Studies --- p.44 / Chapter 3.3.1 --- Animals --- p.44 / Chapter 3.3.2 --- Maintenance of Sarcoma 180 Cell Line --- p.44 / Chapter 3.3.3 --- Effect of DI3 Fraction on Sarcoma 180 Solid Tumor --- p.45 / Chapter 3.3.4 --- Effect of DI3c Fraction on Tumor Necrosis Factor-Alpha (TNF-α) and Interleukin 2 (IL-2) Production --- p.47 / Chapter 3.3.4.1 --- Treatment of Mice --- p.47 / Chapter 3.3.4.2 --- Preparation of Mouse Serum --- p.47 / Chapter 3.3.4.3 --- Enzyme-linked Immunosorbent Assay (ELISA) for TNF-α Production --- p.48 / Chapter 3.3.4.4 --- Enzyme-linked Immunosorbent Assay (ELISA) for IL-2 Production --- p.49 / Chapter 3.4 --- In vitro Studies --- p.51 / Chapter 3.4.1 --- Maintenance of Cell Lines --- p.51 / Chapter 3.4.2 --- Effect on Cancer Cell Lines --- p.52 / Chapter 3.4.3 --- Cytotoxicity on Normal Cell Line --- p.52 / Chapter 3.4.4 --- Trypan Blue Exclusion Method --- p.53 / Chapter 3.4.5 --- MTT Assay --- p.54 / Chapter 3.4.6 --- BrdU Incorporation --- p.55 / Chapter 3.5 --- Statistical Analysis --- p.56 / Chapter Chapter 4 --- Results --- p.57 / Chapter 4.1 --- Extraction and Fractionation of Polysaccharides from Dictyophora indusiata --- p.57 / Chapter 4.1.1 --- Percentage Yield of Crude DI Polysaccharides --- p.57 / Chapter 4.1.2 --- Percentage Yield of DI3 Fractions --- p.57 / Chapter 4.2 --- Characterization of DI3 Fractions --- p.62 / Chapter 4.2.1 --- Polysaccharide and Protein Contents of DI3 Fractions --- p.62 / Chapter 4.2.2 --- Relative Monosaccharide and Uronic Acid Content in Different DI3 Fractions --- p.62 / Chapter 4.2.3 --- Estimated Molecular Weight of DI3 Fractions --- p.65 / Chapter 4.3 --- Antitumor Effect of Dictyophora indusiata Polysaccharides In vivo --- p.70 / Chapter 4.3.1 --- In vivo Antitumor Effect of Crude DI Polysaccharides --- p.70 / Chapter 4.3.2 --- In vivo Antitumor Effect of Various Fractions of DI3 --- p.70 / Chapter 4.3.3 --- Effect of DI3c on TNP-α and IL-2 Production in Mice --- p.78 / Chapter 4.4 --- In vitro Effects of DI3 Fractions on Cell Density and Viability on Normal and Cancer Cell Lines --- p.86 / Chapter 4.4.1 --- Effects of DI3 Fractions on Cell Density and Viability of Human Leukemic HL-60 and K-562 and Mouse Sarcoma 180 Cells --- p.86 / Chapter 4.4.2 --- Effects of DI3 Fractions on the Growth of Human Liver Cancer HepG2 and Normal Monkey Kidney Vero Cells --- p.86 / Chapter 4.4.3 --- Effect of DI3b Fraction on Proliferation of HL-60 Cells Determined by BrdU Incorporation --- p.94 / Chapter Chapter 5 --- Discussions --- p.96 / Chapter 5.1 --- Extraction and Characterization of DI3 Fractions --- p.96 / Chapter 5.2 --- Antitumor Effects of Dictyophora indusiata Polysaccharides --- p.101 / Chapter 5.3 --- Further Studies --- p.109 / Chapter Chapter 6 --- Conclusion --- p.111 / References --- p.113
293

Hapl?tipos de diferentes SNPs no interior do gene EWS em indiv?duos afetados e n?o-afetados pelo sarcoma de Ewing

Silva, D?borah Soares Bispo Santos 30 March 2012 (has links)
Made available in DSpace on 2015-04-14T14:51:17Z (GMT). No. of bitstreams: 1 438120.pdf: 2337312 bytes, checksum: 3bcbd6b2d333489c6e0cefb866d0b73c (MD5) Previous issue date: 2012-03-30 / Ewing s sarcoma was first described by James Ewing in 1921 and it is the second most common bone tumor in children and young adults. Both chromosomal breakage and translocation occur in this sarcoma. The EWS gene is localized in chromosome 22 and is involved in this translocation. However, little is known about this gene breaking region and what sequences could be involved in higher chromosomal break susceptibility. In this study we aimed to investigate three SNPs in the EWS gene breaking region in a healthy subjects population and in Ewing s sarcoma patients. Genotyping was performed by TaqMan? assay for allelic discrimination using Real-Time PCR System. We conducted analysis of allelic and genotypic frequencies, as well as association and transmission disequilibrium tests. According to our results, the control group showed similar and different genotypes distribution of all SNPs when compared to other populations studied by different projects, which shows how important it is to know the frequencies of our population. To test the hypothesis that some SNP, SNParrangement or haplotype could influence in the susceptibility to develop Ewing s sarcoma, we compared affected with non-affected individuals using association studies. The results showed one significant difference: a higher presence of homozygote T-rs4820804 in Ewing s Sarcoma patients. Transmission Disequilibrium Test (TDT) was performed to compare data from Ewing s Sarcoma patients and from their families but no statistically significant result was found. In conclusion, we find that the TT-rs4820804 EWS genotype can be associate with Ewing s sarcoma and that the rs4820804 SNP can be a candidate to understand the EWS breakage susceptibility. / O sarcoma de Ewing foi primeiramente descrito por James Ewing em 1921 e ? o segundo tumor ?sseo mais frequente em crian?as, adolescente e adultos jovens. Neste sarcoma, ? comum ocorrer a quebra e a transloca??o cromoss?mica. Dentre os genes envolvidos nesta transloca??o est? o gene EWS, localizado no cromossomo 22. Entretanto, pouco se sabe a respeito da regi?o de quebra deste gene e quais sequ?ncias poderiam levar a uma maior susceptibilidade a quebra cromoss?mica. Sendo assim, o objetivo deste trabalho foi investigar tr?s polimorfismos de base ?nica (SNPs) presentes na regi?o de quebra do gene EWS, em uma popula??o de indiv?duos saud?veis e em pacientes afetados pelo Sarcoma de Ewing. A genotipagem para os SNPs selecionados foi realizada usando TaqMan SNP Genotyping Assay pelo sistema de PCR em tempo real. N?s realizamos an?lises de frequ?ncias al?licas e genot?picas, assim como um estudo de associa??o e de desequil?brio de transmiss?o. A compara??o das frequ?ncias al?licas e genot?picas entre as popula??es deste estudo e entre popula??es de projetos j? publicados mostrou particularidades entre as popula??es, revelando a import?ncia de se conhecer tais frequ?ncias na popula??o de estudo. Para testar a hip?tese de que algum SNP, hapl?tipo ou combina??o espec?fica de SNPs poderia influenciar na susceptibilidade ao Sarcoma de Ewing, comparamos afetados com n?o-afetados realizando estudos de associa??o cujos resultados mostraram uma ?nica diferen?a significativa: a maior incid?ncia no gen?tipo TT-rs4820804 entre os afetados pelo Sarcoma de Ewing. O Teste de Desequil?brio de Transmiss?o (TDT) comparou os dados dos pacientes afetados e os dados de seus familiares, mas nenhum resultado significativo foi encontrado. Em conclus?o, o gen?tipo TT-rs4820804 pode estar associado ao Sarcoma de Ewing e o SNP rs4820804 pode ser candidato para aux?lio do entendimento da susceptibilidade de quebra do gene EWS.
294

Hapl?tipos de diferentes SNPs no interior do gene FLI1 em indiv?duos afetados e n?o-afetados pelo sarcoma de Ewing

Sawitzki, Fernanda Rosa 30 March 2012 (has links)
Made available in DSpace on 2015-04-14T14:51:17Z (GMT). No. of bitstreams: 1 438127.pdf: 909961 bytes, checksum: 5f9f40febc8291b363b759367f823d98 (MD5) Previous issue date: 2012-03-30 / In this study the SNPs rs640098, rs491714, rs611307 into the FLI1 gene were genotyped in a sample of 201 subjects from southern Brazilian population, in 24 Ewing s sarcoma patients (geographically matched with control group) and 54 of their family members, including parents and siblings. We performed association studies comparing genotypic frequencies of rs640098, rs491714, rs611307 into the FLI1 gene, and all possible genotype combinations between Ewing s Sarcoma patients and control group. Of the three SNPs investigated individually, only one of them showed a significant result when compared to the control group; our non-combined analysis revealed a significantly higher presence of homozygote A-rs497714 among Ewing s Sarcoma patients (p=0.0065; Chi square Test). In all other tested clusters, we always noticed a higher rate of homozygote A-rs497714 among Ewing s Sarcoma patients independent of the other SNP-arrangements and/or haplotype combinations. In addition, we performed transmission disequilibrium tests comparing data from Ewing s Sarcoma patients and from their families (parents and siblings), but no statistically significant result was found. In conclusion, the present study provides evidence statistically founded that the AA-rs497714 FLI1 genotype can associated with Ewing's sarcoma. And that this polymorphism can be clinically useful as a potential genetic marker to the prognostic of risk to develop this cancer or to provide insights into FLI1 chromosome breakage context of tumorigenesis. / Neste estudo, os SNPs rs640098, rs491714, rs611307 no gene FLI1 foram genotipados em uma amostra de 201 indiv?duos da popula??o do sul do Brasil, e em 24 pacientes portadores de Sarcoma Ewing (geograficamente comparado com grupo controle) e 54 de seus familiares, incluindo pais e irm?os. Realizamos estudos de associa??o, comparando as freq??ncias genot?picas do rs640098 e rs491714 e rs611307 no gene FLI1, e todas as combina??es poss?veis entre o gen?tipo de pacientes Sarcoma de Ewing e grupo controle. Dos tr?s SNPs investigados individualmente, apenas um deles apresentou um resultado significativo quando comparado com o grupo controle; nossa an?lise n?o-combinada revelou uma presen?a significativamente maior de homozigoto A-rs497714 entre os pacientes de Sarcoma Ewing (p = 0,0065; Chi quadrado). Em todos os outros grupos testados, foi notada uma maior taxa de homozigoto A-rs497714 entre os pacientes com Sarcoma de Ewing, independentemente dos outros arranjos e / ou combina??es de SNP e hapl?tipos. Al?m disso, foram realizados testes de desequil?brio de transmiss?o, comparando dados de pacientes portadores de Sarcoma de Ewing e de suas fam?lias (pais e irm?os), mas nenhum resultado estatisticamente significativo foi encontrado. Em conclus?o, o presente estudo fornece evid?ncias estatisticamente fundada de que o gen?tipo AA-rs497714 FLI1 pode associado ao sarcoma de Ewing. E que este polimorfismo pode ser clinicamente ?til como um potencial marcador gen?tico para o progn?stico de risco para desenvolver este c?ncer ou para fornecer insights no contexto de quebras cromoss?micas de tumorig?nese no gene FLI1.
295

Analyse du rôle de la voie p53 dans la réponse des sarcomes des tissus mous au traitement par TNF-alpha / Role of p53 pathway in the response of soft tissue sarcomas to TNF-alpha treatment

Muret, Jane 16 December 2011 (has links)
Introduction : Le TNF-a, impliqué dans l’inflammation et la défense de l’hôte, aaussi des propriétés anti-tumorales et est utilisé dans le traitement local des sarcomesdes membres. P53 est un anti-oncogène dont la mutation est associée audéveloppement de tumeurs. Des données expérimentales ont démontré une relationentre activité anti-tumorale de TNF-a et le statut de p53. Matériel et méthodes : Notre objectif a été d’étudier en immunohistochimie lestatut de p53 chez 110 patients atteints de sarcomes et traités par TNF-a. Ensuite,dans 8 sarcomes cultivés ex-vivo, nous avons étudié la localisation de l’apoptoseinduite par le TNF-a par microscopie confocale. Puis, dans 9 lignées de sarcomeshumains, nous avons testé la relation p53/TNF-a en abrogeant p53 grâce à un sh-RNA, ou en utilisant des petites molécules telles que CP-31398 ou Nutlin-3a aptes àrestaurer p53. Enfin, pour mieux comprendre les mécanismes de résistance au TNF-a,nous avons mesuré par méthode EMSA la liaison de NF-kB à l’ADN et recherché parRT-PCR quels gènes de l’apoptose étaient différentiellement régulés.Résultats : Le statut muté de p53 corrèle avec la réponse histologique autraitement par TNF-a chez l’homme. L’apoptose induite par le TNF-a est trouvée aussibien au niveau de la cellule endothéliale que de la cellule tumorale. De plus, laréponse au TNF-a est modulée par le statut de p53 puisque dans les lignées étudiées,l’abrogation de p53 supprime celle-ci alors que la réparation d’une activité p53 permetde l’augmenter. Enfin, une potentialisation de l’apoptose induite par TNF-a estobservée lorsqu’il est associé avec CP-31398 ou Nutlin-3a et elle corrèle avec ladiminution de la liaison du NF-kB à l’ADN. Une augmentation de l’expression desgènes RIPK2, TP53BP2 et GADD45 et une diminution de l’expression de TGF-b1 etFAIM est observée lorsque l’association de Nutlin-3a et TNF-a est synergique sur lamort cellulaire.Conclusions : Ces résultats suggèrent que l’utilisation de molécules capablesde restaurer l’activité de p53 peut inverser la résistance des sarcomes des tissusmous au traitement par TNF-a. Dans ce contexte, des études cliniques pourraientexploiter cette approche pour l’utiliser dans le cadre des sarcomes particulièrementrésistants aux traitements conventionnels ainsi que dans d’autres tumeurs. / Introduction: Although named for its antitumor properties, TNF-a is implicatedin a wide spectrum of diseases including chronic inflammation, autoimmunity andcancer. It is used for the loco regional treatment of limb’s sarcoma. P53 is an antioncogenewhose mutation is associated with tumour development. Experimental datademonstrated that TNF-a cytotoxic activity and p53 status are related.Material and methods: Our objective was to study by immunohistochemistrythe p53 status in 110 sarcoma patients treated by isolated limb perfusion with TNF-a. Then, we studied by confocal microscopy in 8 freshly obtained sarcoma tumours,the localization of apoptosis. Finally, in 9 sarcoma cell lines with different p53 status,we tested the p53/TNF-a relationship by abrogating p53 with a sh-RNA and by usingsmall molecules known to restore p53 functions. To better understand the mechanismsof resistance to TNF-a, we measured by EMSA the NF-kB-binding to DNA and withRT-PCR, we explored the regulation of some apoptosis related genes.Results: We demonstrated a relationship between p53 status and thehistological response to TNF-a use in humans. TNF-a induced apoptosis was presentin endothelial cells as well as in the tumour cells. TNF-a cytotoxicity was dependent onthe p53 status since in the cell lines studied, p53 abrogation reduced it and p53restoration allowed it to increase. Moreover, a potentiation of TNF-a cytotoxic effectwas observed when it was combined to CP-31398 or Nutlin-3a. The killing magnitudewas therefore related to the decrease in the NF-kB-binding to DNA when Nutlin-3awas added. A gene expression increase for RIPK2, TP53BP2 and GADD45 and adecrease for TGF-b1 and FAIM was observed if the combined treatment wassynergistic on tumour death cells.Conclusions: These results suggest that the use of compounds able to restorep53 activity could reverse the soft tissue sarcoma’s resistance to TNF-a treatment.Clinical studies should be performed in order to utilize this approach and to use it inthe context of sarcomas that are particularly resistant to conventional treatments.
296

"Pesquisa de sítios de restrição enzimática em segmento da ORF K1 do genoma de herpesvírus humano tipo 8 (HHV-8) em isolados clínicos de São Paulo: relação com subtipos virais e implantação da técnica de RFLP (Restriction Fragment Length Polymorphism Analyses) para determinar subtipos virais" / "Research of the restriction enzymatic sites in segment from ORF K1 genome HHV-8, isolates from KS-AIDS patients of São Paulo. Standardized a PCR-RFLP (restriction fragment length polymorphism analysis for HHV-8 subtyping"

Moreira, Abdiel Aparecido 22 August 2003 (has links)
A epidemia da Síndrome de Imunodeficiência Adquirida (AIDS) fez aumentar a incidência de sarcoma de Kaposi (SK) em todos os países e o SK passou a ser considerado doença definidora de AIDS. Desde a descoberta de seu agente etiológico, o herpesvírus humano tipo 8 (HHV-8), vários estudos vêm sendo realizados com o objetivo de caracterizar subtipos virais presentes em todas as formas de SK: clássica, endêmica, iatrogênica e epidêmica. Os sistemas rotineiramente usados na subtipagem do HHV-8 têm usado o seqüenciamento de um gene que contém regiões hipervariáveis e que codifica uma glicoproteína de membrana viral (ORF K1). O presente trabalho apresenta um sistema de subtipagem alternativo que se baseia na presença de sítios de restrição enzimática em um pequeno segmento do gene ORF K1, região hipervariável 1 (VR1) e que permite discriminar subtipos virais. A análise de 68 seqüências; 50 que pertenciam a 36 pacientes com sarcoma de Kaposi infectados e não infectados pelo HIV-1 de São Paulo e 18 a protótipos dos subtipos A a E, mostraram mapas de restrição enzimática característicos dos principais subtipos virais descritos até o momento. Tomando como base apenas as enzimas disponíveis comercialmente, foram selecionadas cinco que se mostraram úteis para a subtipagem de HHV-8: Taq I, Nsi I, Hinf I, Hae III e Mse I. Os resultados obtidos com a técnica de PCR-RFLP (reação em cadeia de polimerase associada à análise do polimorfismo de fragmentos de restrição enzimática) mostraram que de 48 espécimes brasileiros previamente classificados como sendo dos subtipos A, B e C por seqüenciamento gênico, todos foram corretamente subtipados pela técnica de PCR-RFLP. Três amostras (duas do subtipo A e uma do B) apresentaram mais um sítio de restrição enzimática além dos descritos como sendo os predominantes. Mais recentemente, outras 27 amostras de 18 casos de infecção por HHV-8 foram subtipadas pela PCR-RFLP. Houve detecção de oito isolados do subtipo A, sendo seis de variante predominante, um de variante minoritária conhecida e um de nova variante viral. Dois casos de infecção por HHV-8 do subtipo B e sete do subtipo C também foram identificados. Finalmente, um provável caso de infecção pelo subtipo E foi encontrado em paciente com SK-AIDS disseminado, resistente à quimioterapia. Na avaliação global, houve maior número de casos de infecção por HHV-8 dos subtipos A e C. Concluindo, devido à alta sensibilidade e especificidade, baixo custo, rapidez e facilidade de execução, a técnica de PCR-RFLP pode ser usada em larga escala para estudos de epidemiologia molecular, principalmente em países em desenvolvimento. / AIDS epidemic has increased the incidence rates of Kaposi’ s sarcoma (KS) in all countries, and KS has been considered an AIDS-defining illness. Since the discovery of the human herpesvirus 8 (HHV-8), the etiological agent of KS, several studies have been conducted in order to characterize HHV-8 in all forms of KS: classic, endemic, iatrogenic, and epidemic. The HHV-8 genome presents a hypervariable region termed ORF K1 useful for virus subtyping. The objectives of the present study were to describe an alternative method for subtyping HHV-8, to compare this new method with DNA sequencing, and to use this method for HHV-8 subtyping. After cloning and sequencing a segment of the ORF K1 (VR1) in 50 HHV-8/DNA isolates from 36 Brazilian KS-AIDS patients, we searched for restriction enzymatic sites in this segment of DNA, and compared them with 18 sequences reported in the literature. Then we constructed the enzymatic restriction maps useful for discriminating all HHV-8 subtypes described up to now, and standardized a PCR-RFLP (restriction fragment length polymorphism analysis) using five commercial enzymes: Taq I, Nsi I, Hinf I, Hae III e Mse I. After comparing the results obtained by the two methods, we used PCR-RFLP for HHV-8 subtyping in 27 new HHV-8/DNA isolates. The results obtained by DNA sequencing and PCR-RFLP showed 100% of concordance, and allowed the use of PCR-RFLP for HHV-8 subtyping. Indeed, we disclosed that among KS-AIDS patients from São Paulo, subtypes A and C are more prevalent than subtype B. Although additional restriction sites were detected in some Brazilian HHV-8 isolates, the majority of them belonged to the predominant strains described in the literature. Interestingly, one probable case of HHV-8 subtype E was detected in a patient who presented disseminated KS and resistance to chemotherapy. Because of its high sensitivity, specificity, low cost, and rapid execution, PCR-RFLP could be used on a large scale, mostly in countries with poor resources and where KS is endemic.
297

Sarcomas cutâneos primários: estudo retrospectivo de casos registrados na divisão de Dermatologia do Hospital das Clínicas da FMUSP no período de 1992 a 2002 / Primary cutaneous sarcomas: a retrospective study of cases studied in the Dvision of Dermatology of Hospital das Clínicas, São Paulo University Medical School from 1992 to 2002

Fleury Junior, Luiz Fernando Froes 28 March 2007 (has links)
Os sarcomas cutâneos primários são tumores raros e de grande heterogeniedade histológica. Com a evolução da oncologia cutânea e da cirurgia dermatológica, os dermatologistas têm sido cada vez mais requisitados para diagnóstico e orientação terapêutica de tumores menos freqüentes. Entretanto são escassos os estudos sobre o tema, sobretudo na literatura nacional. O presente trabalho apresenta como objetivos estudar casos diagnosticados como sarcoma cutâneo primário pelo Laboratório de Dermatopatologia da Divisão de Dermatologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo no período de 1992 a 2002. Os casos levantados foram revisados histologicamente, selecionando 65 casos que foram classificados em subtipos histológicos. Foi realizado revisão de prontuários médicos e estudadas as características demográficas, clínicas, evolutivas, histológicas e imuno-histoquímicas. O sarcoma de Káposi foi excluído deste estudo por possuir características epidemiológicas e etiopatogênicas específicas. Dos 65 casos, 34 foram de dermatofibrossarcoma protuberans (DFSP), 10 angiossarcomas, cinco sarcomas epitelióides, quatro fibroxantomas atípicos, três leiomiossarcomas, três mixofibrossarcomas, dois sarcomas pleomórficos, um fibrohistiocitoma maligno, um lipossarcoma, um rabdomiossarcoma, um fibrossarcoma. A análise dos resultados permitiu avaliar o perfil epidemiológico, clínico, anatomopatológico e imuno-histoquímico dos casos, bem como os tratamentos empregados e evolução dos pacientes. Os achados epidemiológicos deste estudo não diferiram significativamente da bibliografia consultada, demonstrando tratar-se de tumores raros representando cerca de um caso para cada 1000 biópsias neste serviço no mesmo período. Quanto a distribuição por idade e sexo os dados foram superponíveis à literatura com exceção feita ao angiossarcoma que mostrou-se mais freqüente no sexo feminino. A cirurgia micrográfica mostrou ser o melhor método para abordagem terapêutica do DFSP. Os casos de angiossarcoma e sarcoma epitelióide apresentaram pior prognóstico. / Soft tissue tumours represent a heterogeneous group of mesenchymal and neural lesions. The cutaneous presentation of these tumours is rare. With the evolution of dermatologic surgery and cutaneous oncology, dermatologists have emerged as the primary physicians for skin cancers management. The lack of epidemiological data about this topic in the brazilian population guided us to present this study. Our goal was to systematically review cases of primary cutaneous sarcomas diagnosed at the Dermatophatology laboratory of the Dermatology division of Hospital das Clínicas of São Paulo from January 1992 to December 2002. After a thorough chart review we could retrieve demographic and clinical data, histopathological and immunohistochemical characteristics, in addition to the type of treatment, response to treatment and follow up from each case studied. Kapos\'s sarcoma due to its peculiar characteristics was not included in this study. A total of 65 cases of primary cutaneous sarcoma were included. In respect to its pathological characterization 34 cases were diagnosed dermatofibrosarcoma protuberans (DFSP), 10 angiosarcoma, five epithelioid sarcoma, four atipical fibroxanthoma, tree leiomyosarcoma, tree myxofibrosarcoma, two pleomorfic sarcoma, one malignant fibrohistiocytoma, one liposarcoma, one rabdomyossarcoma, one fibrossarcoma. Our findings were in agreement with international published data available after a medline search. In summary, sarcomas with primary cutaneous presentation are rare tumors with an incidence of 0.1% from all the pathology slides received in our service during this period. Angiosarcoma and epithelioid sarcomas had the worse prognosis and micrographic surgery was the best treatment for the DFSP.
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Imunomarcação de proteínas relacionadas à apoptose em mastocitomas cutâneos caninos e seu valor como indicador prognóstico / Immunostaining of apoptosis-related proteins in canine cutaneous mast cell tumors and its value as prognostic indicators

Camila Neri Barra 18 August 2015 (has links)
A desregulação da apoptose, principalmente da via mitocondrial, exerce papel na progressão tumoral, resistência à quimioterapia, além de favorecer a formação de metástases por permitir a sobrevivência de células tumorais na circulação e outros microambientes teciduais. No presente estudo, foram avaliados 58 mastocitomas cutâneos caninos, provenientes de 50 animais submetidos à cirurgia excisional como única forma de tratamento. Os tumores foram graduados de acordo com o sistemas de estabelecidos por Patnaik, Ehler e MacEwen (1984) e Kiupel et al. (2011). As expressões das proteínas relacionadas à via intrínseca da apoptose, BCL2, BAX, APAF1, Caspase 9 e Caspase 3, foram caracterizadas por meio de imuno-histoquímica. Os resultados obtidos das imunomarcações foram comparados às graduações histopatológicas, bem como à mortalidade em função do tumor e ao tempo de sobrevida pós-cirúrgico. Observamos maior expressão de BAX em mastocitomas de grau III, bem como menor expressão de BCL2 em tumores de alto grau. A detecção imuno-histoquímica de BAX foi considerada um indicador prognóstico para sobrevida e mortalidade em função da doença, enquanto que as de APAF1 e BCL2 adicionaram valor prognóstico às graduações histopatológicas melhorando a previsão da sobrevida pós-cirurgia / Deregulation of apoptosis, especially in the mitochondrial pathway, plays a role in tumor progression, resistance to chemotherapy, and favor the formation of metastases by allowing the survival of tumor cells in the blood stream and other tissue microenvironments. In the present study, we evaluated 58 canine cutaneous mast cell tumors, from 50 dogs, which were submitted to excisional surgery alone. The tumors were graded according to the systems proposed by Patnaik, Ehler and MacEwen (1984) and Kiupel et al. (2011). The expression of the apoptosis-related proteins BCL2, BAX, APAF1, caspase 9 and caspase 3 was characterized by immunohistochemistry. Immunohistochemical results were compared with the histopathological grades, mortality due to the tumor and post-surgical survival time. We observed increased expression of BAX in grade III mast cell tumors and lower expression of BCL2 in high-grade tumors. Immunohistochemical detection of BAX was considered an independent indicator of prognosis for survival and mortality due to the disease, whereas APAF1 and BCL2 added prognostic value to the histopathological grading systems improving the prediction of survival post surgery
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EWSR1-FLI1 et la dissémination métastatique du sarcome d'Ewing : étude des mécanismes moléculaires mis en jeu lors de la migration et de l'invasion cellulaire / EWSR1-FLI1 and Ewing sarcoma metastatic dissemination : study of the molecular mechanisms involved in cell migration and invasion

Brisac, Alice 29 November 2017 (has links)
Le sarcome d’Ewing est une tumeur pédiatrique de l’os très agressive, généralement causée par une translocation chromosomique aboutissant à la protéine de fusion EWSR1-FLI1 qui dérégule l’expression d’un grand nombre de gènes participant à l’oncogenèse du sarcome d’Ewing. Au laboratoire, nous avons pu mettre en évidence une hétérogénéité intra-tumorale de l’expression d’EWSR1-FLI1 aboutissant à un nouveau modèle de la biologie du sarcome d’Ewing basé sur la coexistence de cellules EWSR1-FLI1high, participant à la prolifération de la tumeur primaire, et de cellules EWSR1-FLI1low, capables de dissémination métastatique. Au cours de ma thèse, je me suis intéressée en particulier aux mécanismes moléculaires sous-jacents aux capacités migratoires et invasives des cellules EWSR1-FLI1low. Nous avons ainsi pu mettre en évidence une diminution des jonctions serrées intercellulaires associée à une augmentation des interactions cellule-matrice chez les cellules EWSR1 FLI1low. Nous avons ensuite révélé le rôle clé des MMP dans l’invasion du sarcome d’Ewing, plus spécifiquement de la MMP2 et de la MT1-MMP qui sont toutes deux réprimées par EWSR1-FLI1 et sont apparues nécessaires à l’invasion des cellules EWSR1-FLI1low. L’un des défis majeurs actuels est de parvenir à visualiser cette sous-population très minoritaire et à suivre la plasticité de l’expression d’EWSR1-FLI1. Pour cela, l’identification de marqueurs des cellules EWSR1-FLI1low est cruciale. Ceci est également important pour déterminer si les chimiothérapies actuelles, qui ciblent plutôt les cellules prolifératives, n’entraînent pas une augmentation de la proportion de ces cellules au sein de la tumeur primaire. Enfin, nos essais infructueux d’utilisation de l’embryon de poulet comme nouveau modèle de la métastase du sarcome d’Ewing in vivo ont souligné la fragilité globale et les limitations de ce type de modèle, indiquant plutôt la nécessité d’améliorer les modèles murins existants. La mise au point de modèles in vivo apparaît en effet primordiale pour mieux disséquer les mécanismes moléculaires de la métastase et permettre le test de drogues susceptibles d’inhiber ce processus. / Ewing sarcoma is a very aggressive pediatric bone tumor generally caused by a chromosomal translocation that leads to the expression of the EWSR1-FLI1 fusion protein. This protein deregulates the expression of a number of genes involved in Ewing sarcoma oncogenesis. In the laboratory, we discovered an intra-tumor heterogeneity of EWSR1-FLI1 expression which lead us to propose a new model for Ewing sarcoma biology based on the coexistence of EWSR1-FLI1high cells, responsible for primary tumor growth, and EWSR1-FLI1low cells, with metastatic dissemination capacities. During my phD, I was especially interested in the molecular mechanisms underlying the migration and invasion capacities of EWSR1-FLI1low cells. We showed a decreased expression of intercellular junctions proteins associated with an increased expression of cell-matrix interaction proteins in EWSR1-FLI1low cells. We then revealed the key role of MMPs in Ewing sarcoma invasion, in particular of MMP2 and MT1-MMP, which are both repressed by EWSR1-FLI1 and were found necessary for invasion of EWSR1-FLI1low cells. One of the current major challenges is to visualize this very small sub-population and to track the plasticity of expression of EWSR1-FLI1. To this end, the identification of markers of EWSR1-FLI1low cell is crucial. This is also important in order to determine if current chemotherapies that primarily target highly proliferative cells do not increase the proportion of these EWSR1-FLI1low cells. Finally, our unsuccessful attempts to use the chick embryo as a new in vivo model of Ewing sarcoma metastasis indicate the need to improve the existing murine models. Indeed, the development of in vivo models appears essential for the dissection of the molecular mechanisms of Ewing sarcoma metastasis and the test of drugs susceptible to inhibit this process.
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Locally Recurrent Malignant Fibrous Histiocytoma: A Rare and Aggressive Genitourinary Malignancy

Fröhner, Michael, Manseck, Andreas, Haase, Michael, Hakenberg, Oliver W., Wirth, Manfred P. 17 February 2014 (has links) (PDF)
Objective: In this study, 22 cases of locally recurrent urological malignant fibrous histiocytoma were reviewed considering therapeutic options, follow-up and prognosis. Patients and Methods: In the available literature on this topic we identified 19 cases of locally recurrent genitourinary malignant fibrous histiocytoma. Three additional cases are discussed, primarily arising from the kidney, the bladder and the paratesticular region. Results: The prognosis of locally recurrent urological malignant fibrous histiocytoma was found to be extraordinarily poor. Only 2 of 22 patients have survived for longer than 3.5 years. One of them reported herein is still alive 10 years after extensive lymphatic spread accompanying the first local recurrence. In this case, late local recurrence occurred after an 8-year interval free of disease. Conclusion: Malignant fibrous histiocytoma is an unusual urological malignancy with a high rate of local recurrence. The latter is frequently accompanied by metastatic disease and unrelenting progression. Despite the poor prognosis early detection of local failure and aggressive salvage therapy might offer the chance of long-term survival in selected cases. Close and life-long follow-up is advisable for patients once treated for recurrent urological malignant fibrous histiocytoma. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

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