• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 18
  • 7
  • 5
  • 4
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 36
  • 36
  • 16
  • 15
  • 14
  • 13
  • 9
  • 8
  • 8
  • 8
  • 7
  • 6
  • 6
  • 6
  • 4
  • 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

Análise Citogenética Clássica e Molecular para os Genes Aurora Cinase A e B em Células Hematopoéticas e Mesenquimais da Medula Óssea de Pacientes Portadores de Síndrome Mielodisplásica / Classical Cytogenetic Analysis and Molecular for Genes Aurora Kinase A and B in Hematopoietic Cells and Mesenchymal Bone Marrow of Patients with Myelodysplastic Syndrome

Sabrina Dias Leite Cueva 10 August 2012 (has links)
A síndrome mielodisplásica (SMD) é uma doença hematológica heterogênea, caracterizada por hematopoese anormal, displasia e instabilidade genômica, portanto, a análise citogenética é determinante no diagnóstico, prognóstico e acompanhamento evolutivo da doença. Considerando que as células hematopoéticas (CHs) e as estromais mesenquimais multipotentes (CTMs) estão em estreita associação, estudos que visem à caracterização destas poderão contribuir para elucidar os mecanismos que governam a progressão tumoral e identificar novos alvos terapêuticos. Objetivo: Caracterizar e comparar as CHs e CTMs derivadas de pacientes através da citogenética convencional e molecular para os genes aurora cinase A e B. Avaliar as propriedades biológicas das CTMs derivadas de SMD e controles saudáveis. Métodos: o estudo iniciou-se com a avaliação clinica de 25 pacientes e 8 controles saudáveis doo HCFMRP-USP e HAC-Jaú. Em seguida, foi realizada a análise cariótipica das CHs e CTMs da medula óssea pelo bandamento G e por FISH para os genes aurora A e B e o perfil imunofenotípico, bem como potencial de diferenciação em adipócito e osteócito das CTMs de pacientes portadores de SMD e controles saudáveis. Resultados: A avaliação clínica mostrou plaquetopenia (76%), neutropenia (100%), hemoglobina baixa (16%). A análise citogenética das CHs revelou cariótipo alterado em 13 pacientes (52%), com cariótipo complexo resultando em alterações numéricas e estruturais. Ao contrário, nas CTMs, o cariótipo se mostrou alterado em sete pacientes (28%) e um padrão de menor complexidade, apenas quatro pacientes apresentaram alterações nas duas populações celulares, porém, diferentes. Foram encontradas apenas alterações numéricas (sendo 86% monossomia e 14% ganho de cromossomo). As CHs e CTMs dos controles apresentaram cariótipos 100% normais. Na análise de FISH não foi evidenciada amplificação dos genes AURKA e AURKB. As CTMs dos pacientes e controles apresentaram-se semelhantes quanto à morfologia e potencial de diferenciação. Entretanto, as CTMs de pacientes mostraram-se alteradas para dois antígenos de superfície, CD90 e CD146, os quais mostraram níveis de expressão mais elevados nas amostras dos pacientes (p= 0,04, p = 0,001 respectivamente). Conclusão: Observou-se que as CTMs se encontram alteradas embora em menor frequência e diferindo das alterações encontradas nas CHs. Esses dados sugerem que as CTMs devem exercer importante papel na progressão tumoral e devem ser consideradas como alvos na busca de novas terapias e melhor esclarecimento dos mecanismos que governam a progressão tumoral. Apesar de não ter evidenciado amplificação dos genes AURKA e AURKB em SMD, estudos futuros que visem avaliar o nível de expressão dessas enzimas em pacientes portadores ou não de alterações citogenéticas poderão contribuir para a compreensão do envolvimento ou não desse gene com a evolução da doença. Além disso, não foi evidenciada associação de anemia profunda e citogenética alterada. / The myelodysplastic syndrome (MDS) is a heterogeneous hematologic disease characterized by abnormal hematopoiesis, dysplasia and genomic instability, therefore, cytogenetic analysis is crucial in the diagnosis, prognosis and monitoring of disease evolution. Whereas hematopoietic cells (CHs) and stromal multipotent mesenchymal (MSCs) are in close association studies aimed at the characterization of these may help to elucidate the mechanisms that govern tumor progression and identify novel therapeutic targets. Objective: To characterize and compare the CHs and MSCs derived from patients by conventional cytogenetics and molecular genes aurora kinase A and B. To evaluate the biological properties of MSCs derived from MDS and healthy controls. Methods: The study began with the clinical evaluation of 25 patients and eight healthy controls HCFMRP dooUSP and CH-Jau. Next, we performed a karyotypic analysis of CHs and MSCs from bone marrow by G-banding and FISH for aurora A and B genes and immunophenotypic profile and potential to differentiate into adipocytes and osteocytes of MSCs in patients with MDS and controls healthy. Results: The clinical evaluation showed thrombocytopenia (76%), neutropenia (100%), low hemoglobin (16%). The cytogenetic analysis revealed karyotype of CHs changed in 13 patients (52%), resulting in complex karyotype with numerical and structural changes. In contrast, in MSC, the karyotype was abnormal in seven patients (28%) and a pattern of lower complexity, only four patients had changes in both cell populations, however, different. Were found only numerical changes (monosomy being 86% and 14% gain in chromosome). The CHs and MSCs controls showed 100% normal karyotypes. In FISH analysis there was no evidence of gene amplification and AURKA AURKB. The MSCs of patients and controls were similar regarding the morphology and differentiation potential. However, the CTMs of patients proved to be changed to two surface antigens, CD90 and CD146, which showed higher expression levels in samples of patients (p = 0.04, p = 0.001 respectively). Conclusion: Furthermore, it was observed that the MSCs are changed although less frequently and differing from changes found in CHs. These data suggest that MSCs should play an important role in tumor progression and should be considered as targets in the search for new therapies and better explain the mechanisms that govern tumor progression. Although not shown AURKA amplification of genes in MDS and AURKB, future studies aimed at assessing the level of expression of these enzymes in patients with or without cytogenetic alterations may contribute to the understanding of the involvement or not of this gene with the disease. This study can not associate with profound anemia cytogenetic changes.
12

Effects of overexpression of syndecan-1 in mesenchymal tumor cells

Grönkvist, Pamela January 2011 (has links)
BackgroundAll cells carry a transmembrane proteoglycan calledsyndecan. Syndecans influence many functions like cell migration, cell adhesionand cell proliferation and it is involved in cellular signaling andtumourigenesis. The common features of differentiation in twomesenchymal tumor cell types, malignant mesothelioma cells and fibrosarcoma cells,are connected to the synthesis of syndecans. By studying the overexpression ofsyndecan-1 we hope to discover new features of the syndecan-1 molecule that wecan add to the puzzle of mesenchymal tumors. Methods and findingsMalignant mesothelioma cells and fibrosarcoma cellswere cultured and transfected with full-length- and truncated syndecan-1 constructs.To detect the expression of syndecan-1 on RNA level Rt-Q-PCR was conductedfollowed by immunocytochemical analysis to establish the syndecan-1 expressionon protein level. The result showed a 2-7 fold increase of syndecan-1 in thetransfectants comparing to the control. The proliferation of transfectants was analyzedby cell proliferation assay and cell cycle analysis. All transfectants showed alower proliferation rate comparing to the controls and a slight increase inG0/G1 phase. Because of the high structural similarities ofsyndecan family members, I studied how overexpression of syndecan-1 affected theother syndecans using Rt-Q-PCR. Syndecan-2 and -4 were downregulated in thetransfectants carrying syndecan-1 ectodomain, whereas the truncated versionshad the opposite effect. The expression of syndecan-bound heparan sulfate wasstudied by FACS and indicated an upregulation for heparan sulfate whenmeasuring internal- and membrane bound syndecans simultanesly. ConclusionsIn this study I haveshown that overexpression of full-length syndecan-1 and the different truncatedvariants, had similar profound effects on mesenchymal cell proliferation. Syndecan-1also influences the other members of the syndecan family suggesting a complexregulation.
13

Análise Citogenética Clássica e Molecular para os Genes Aurora Cinase A e B em Células Hematopoéticas e Mesenquimais da Medula Óssea de Pacientes Portadores de Síndrome Mielodisplásica / Classical Cytogenetic Analysis and Molecular for Genes Aurora Kinase A and B in Hematopoietic Cells and Mesenchymal Bone Marrow of Patients with Myelodysplastic Syndrome

Cueva, Sabrina Dias Leite 10 August 2012 (has links)
A síndrome mielodisplásica (SMD) é uma doença hematológica heterogênea, caracterizada por hematopoese anormal, displasia e instabilidade genômica, portanto, a análise citogenética é determinante no diagnóstico, prognóstico e acompanhamento evolutivo da doença. Considerando que as células hematopoéticas (CHs) e as estromais mesenquimais multipotentes (CTMs) estão em estreita associação, estudos que visem à caracterização destas poderão contribuir para elucidar os mecanismos que governam a progressão tumoral e identificar novos alvos terapêuticos. Objetivo: Caracterizar e comparar as CHs e CTMs derivadas de pacientes através da citogenética convencional e molecular para os genes aurora cinase A e B. Avaliar as propriedades biológicas das CTMs derivadas de SMD e controles saudáveis. Métodos: o estudo iniciou-se com a avaliação clinica de 25 pacientes e 8 controles saudáveis doo HCFMRP-USP e HAC-Jaú. Em seguida, foi realizada a análise cariótipica das CHs e CTMs da medula óssea pelo bandamento G e por FISH para os genes aurora A e B e o perfil imunofenotípico, bem como potencial de diferenciação em adipócito e osteócito das CTMs de pacientes portadores de SMD e controles saudáveis. Resultados: A avaliação clínica mostrou plaquetopenia (76%), neutropenia (100%), hemoglobina baixa (16%). A análise citogenética das CHs revelou cariótipo alterado em 13 pacientes (52%), com cariótipo complexo resultando em alterações numéricas e estruturais. Ao contrário, nas CTMs, o cariótipo se mostrou alterado em sete pacientes (28%) e um padrão de menor complexidade, apenas quatro pacientes apresentaram alterações nas duas populações celulares, porém, diferentes. Foram encontradas apenas alterações numéricas (sendo 86% monossomia e 14% ganho de cromossomo). As CHs e CTMs dos controles apresentaram cariótipos 100% normais. Na análise de FISH não foi evidenciada amplificação dos genes AURKA e AURKB. As CTMs dos pacientes e controles apresentaram-se semelhantes quanto à morfologia e potencial de diferenciação. Entretanto, as CTMs de pacientes mostraram-se alteradas para dois antígenos de superfície, CD90 e CD146, os quais mostraram níveis de expressão mais elevados nas amostras dos pacientes (p= 0,04, p = 0,001 respectivamente). Conclusão: Observou-se que as CTMs se encontram alteradas embora em menor frequência e diferindo das alterações encontradas nas CHs. Esses dados sugerem que as CTMs devem exercer importante papel na progressão tumoral e devem ser consideradas como alvos na busca de novas terapias e melhor esclarecimento dos mecanismos que governam a progressão tumoral. Apesar de não ter evidenciado amplificação dos genes AURKA e AURKB em SMD, estudos futuros que visem avaliar o nível de expressão dessas enzimas em pacientes portadores ou não de alterações citogenéticas poderão contribuir para a compreensão do envolvimento ou não desse gene com a evolução da doença. Além disso, não foi evidenciada associação de anemia profunda e citogenética alterada. / The myelodysplastic syndrome (MDS) is a heterogeneous hematologic disease characterized by abnormal hematopoiesis, dysplasia and genomic instability, therefore, cytogenetic analysis is crucial in the diagnosis, prognosis and monitoring of disease evolution. Whereas hematopoietic cells (CHs) and stromal multipotent mesenchymal (MSCs) are in close association studies aimed at the characterization of these may help to elucidate the mechanisms that govern tumor progression and identify novel therapeutic targets. Objective: To characterize and compare the CHs and MSCs derived from patients by conventional cytogenetics and molecular genes aurora kinase A and B. To evaluate the biological properties of MSCs derived from MDS and healthy controls. Methods: The study began with the clinical evaluation of 25 patients and eight healthy controls HCFMRP dooUSP and CH-Jau. Next, we performed a karyotypic analysis of CHs and MSCs from bone marrow by G-banding and FISH for aurora A and B genes and immunophenotypic profile and potential to differentiate into adipocytes and osteocytes of MSCs in patients with MDS and controls healthy. Results: The clinical evaluation showed thrombocytopenia (76%), neutropenia (100%), low hemoglobin (16%). The cytogenetic analysis revealed karyotype of CHs changed in 13 patients (52%), resulting in complex karyotype with numerical and structural changes. In contrast, in MSC, the karyotype was abnormal in seven patients (28%) and a pattern of lower complexity, only four patients had changes in both cell populations, however, different. Were found only numerical changes (monosomy being 86% and 14% gain in chromosome). The CHs and MSCs controls showed 100% normal karyotypes. In FISH analysis there was no evidence of gene amplification and AURKA AURKB. The MSCs of patients and controls were similar regarding the morphology and differentiation potential. However, the CTMs of patients proved to be changed to two surface antigens, CD90 and CD146, which showed higher expression levels in samples of patients (p = 0.04, p = 0.001 respectively). Conclusion: Furthermore, it was observed that the MSCs are changed although less frequently and differing from changes found in CHs. These data suggest that MSCs should play an important role in tumor progression and should be considered as targets in the search for new therapies and better explain the mechanisms that govern tumor progression. Although not shown AURKA amplification of genes in MDS and AURKB, future studies aimed at assessing the level of expression of these enzymes in patients with or without cytogenetic alterations may contribute to the understanding of the involvement or not of this gene with the disease. This study can not associate with profound anemia cytogenetic changes.
14

Functional characterisation of the mesenchymal cell-derived extracellular matrix in myelodysplastic neoplasms

Bains, Amanpreet Kaur 08 January 2024 (has links)
Myelodysplastic neoplasms (MDS) are a group of heterogeneous, clonal disorders characterised by ineffective haematopoiesis and peripheral blood cytopenia. MDS is highly progressive, difficult to treat, and is one of the most common blood cancers, affecting 4-5/100.000 people below the age of 70 and many more thereafter. Single or multiple driver gene mutations and chromosomal abnormalities in the haematopoietic compartment lead to MDS. These somatic gene mutations account for the dysregulation of epigenetic, DNA repair, cohesion complex, and spliceosome pathways. The International prognostic scoring system (IPSS) that was developed in 1997, revised (IPSS-R) in 2016 and updated in 2022 (IPSS-M) classifies MDS into low risk (LR-), intermediate (Int-), and high risk (HR-) groups. The haematopoietic disorder is accompanied by changes in the bone marrow microenvironment (BMME) and especially in mesenchymal cells (MSCs). BMME provides a supportive milieu for haematopoiesis and can be targeted by clinically available drugs such as AZA. The non cellular component of the BMME, the extracellular matrix (ECM), is a framework providing structural and biochemical support via cell-ECM interactions and the maintenance of growth factor gradients. To date, studies of bone marrow interactions in homeostasis and disease have focused largely on soluble and membrane-associated factors, while the involvement of the ECM in MDS and its response to therapy is underexplored. Therefore, this study aimed to characterise the MDS MSC derived ECM of both LR- and HR-MDS in comparison to that from healthy age matched donors in terms of composition, biophysical properties and functional haematopoietic support. This study also aimed to evaluate the impact of in vivo and in vitro AZA treatment on MDS MSC derived ECM. To investigate this, in vitro ECMs were generated by culturing of MSC monolayers on chemically prepared coverslips followed by decellularization using NH4OH and DNase-1 solution. The biophysical properties of the ECM were analysed using atomic force microscopy (AFM). Using targeted approaches, a selection of biochemical ECM components including glycoprotein (fibronectin), collagens and glycosaminoglycans (GAGs) were analysed in the various ECMs generated from the different MSC samples. AFM analysis revealed that MDS MSCs producer a softer ECM than the healthy donor MSCs, and that this difference becomes more prominent as the disorder progresses from LR-to HR- MDS. An increase in overall collagen content and a specific increase in collagens I and IV was observed in the ECM deposited by both LR- and HR-MDS MSCs when compared to healthy donor MSCs. Lectin staining revealed disease stage-specific differences in GAG composition: The levels of GAGs carrying N acetyl glucosamine and those carrying N-acetyl galactosamine sugars were both increased in ECM from LR-MDS, while ECM from HR-MDS retained high levels of N acetyl glucosamine but contained only low levels of N-acetyl galactosamine GAGs. The changes in N acetyl galactosamine and N acetyl glucosamine GAGs were further confirmed by chondroitin sulphate (CS) immunostaining, and hyaluronic acid (HA) ELISA respectively. Electrophoretic analysis revealed the presence of low molecular weight (LMW)-HA in one of the LR-MDS MSC derived ECM. Furthermore, the stimulation of MNCs with LMW-HA showed an increase in gene expression of pro-inflammatory cytokines like IL6 suggesting the possible involvement of LMW-HA in the inflammatory bone marrow state of LR-MDS. ECM derived from both LR- and HR-MDS MSCs had a reduced ability to support HSPC, as revealed by a loss of both polar morphology and subsequent colony-forming potential. The decreased rigidity of the ECM produced by MSCs from MDS patients was reversed in MSCs isolated from the patients post-AZA therapy. Similarly, direct exposure of cultured MDS MSCs to AZA also resulted in a corresponding increase in the rigidity of the ECM, although this remained lower than that observed from MDS MSCs isolated post-AZA therapy. A reduction in the collagen content of the ECM was only observed when using MSC from AZA-treated patients, but not following in vitro AZA treatment of MSCs from untreated patients. This indicated that the AZA-mediated restoration of ECM rigidity is an indirect result of effects in the context of the BMME and not on the MSCs alone. Interestingly, a few ECMs derived from MDS patients after AZA therapy had an improved ability to maintain functional HSPCs, as assessed by subsequent colony formation assay. Moreover, a polarized morphology of HSPCs cultured on the ECM derived from both in vivo and in vitro AZA-treated MDS MSCs, suggests a partial restoration of the HSPC behaviour on the AZA-treated MDS ECM. In conclusion, this study has demonstrated changes in the structure, collagen content, and GAG composition of ECM derived from MSCs from MDS patients compared to healthy donors. This study is one of the first to demonstrate an impact of MDS-derived ECM on both the morphology and function of HSPCs, supporting the relevance of the bone marrow ECM in haematological malignancies. The partial revision of the MDS ECM phenotype following in vivo AZA treatment suggests that the ECM itself may be a potential therapeutic target. An improved, in-depth understanding of the contribution of ECM to disease processes is therefore likely to enable us to find novel therapeutic targets to improve drug response in MDS in the future. / Myelodysplastische Neoplasien (MDS) sind eine Gruppe heterogener, klonaler Erkrankungen, die durch ineffektive Hämatopoese und Zytopenie des peripheren Blutes gekennzeichnet sind. MDS sind hochgradig progressiv, schwer zu behandeln und gehören zu den häufigsten Blutkrebserkrankungen, von denen 4-5/100.000 Menschen unter 70 Jahren betroffen sind. Die Inzidenz steigt mit zunehmendem Alter deutlich an. MDS wird durch einzelne oder mehrfache Mutationen von Treibergenen und Chromosomenanomalien im hämatopoetischen Kompartiment verursacht. Diese somatischen Genmutationen sind für die Dysregulation von epigenetischen, DNA-Reparatur-, Kohäsionskomplex- und Spleißosomen-Signalwegen verantwortlich. Das Internationale Prognosesystem (IPSS) wurde 1997 entwickelt, 2016 überarbeitet (IPSS-R) und 2022 aktualisiert (IPSS M), um MDS in Gruppen mit niedrigem Risiko (LR-), mittlerem (Int ) und hohem Risiko (HR-) einzuteilen. Die hämatopoetische Erkrankung geht mit Veränderungen in der Mikroumgebung des Knochenmarks (BMME) einher, insbesondere bei mesenchymalen Zellen (MSCs). Das BMME bietet ein unterstützendes Milieu für die Hämatopoese und kann durch klinisch verfügbare Medikamente wie AZA beeinflusst werden. Die nichtzelluläre Komponente der BMME, die extrazelluläre Matrix (ECM), ist ein Gerüst, das durch Zell-ECM-Interaktionen und die Aufrechterhaltung von Wachstumsfaktorgradienten strukturelle und biochemische Unterstützung bietet. Bislang haben sich Studien über die Interaktionen im Knochenmark bei Homöostase und Krankheit hauptsächlich auf lösliche und membranassoziierte Faktoren konzentriert, während die Beteiligung der ECM an MDS und ihre Reaktion auf die Therapie noch nicht ausreichend erforscht ist. Daher zielte diese Studie darauf ab, die aus MDS-MSCs abgeleitete ECM sowohl bei LR- als auch bei HR-MDS im Vergleich zu der von gesunden, altersgleichen Spendern zu charakterisieren, und zwar hinsichtlich der Zusammensetzung, der biophysikalischen Eigenschaften und der funktionellen hämatopoetischen Unterstützung. Ziel dieser Studie war es auch, die Auswirkungen einer in vivo und in vitro AZA-Therapie auf die aus MDS-MSCs stammende ECM zu untersuchen. Hierfür wurden in vitro ECMs durch Kultivierung von MSC-Monolayern auf chemisch-präparierten-Deckgläsern und anschließender Dezellularisierung mit NH4OH und DNase-1-Lösung erzeugt. Die biophysikalischen Eigenschaften der ECM wurden mittels Rasterkraftmikroskopie (AFM) analysiert. Mit gezielten Ansätzen wurde eine Auswahl biochemischer ECM-Komponenten, darunter Glykoproteine (Fibronektin), Kollagene und Glykosaminoglykane (GAGs), in den ECMs analysiert. Die AFM-Analyse ergab eine weichere ECM, die von MDS-MSCs im Vergleich zu gesunden Spender-MSCs gebildet wurde, was mit dem Fortschreiten der Erkrankung von LR- zu HR-MDS noch deutlicher wurde. Sowohl in LR-MDS- als auch in HR-MDS-ECMs wurde im Vergleich zu gesunden Spender-ECMs ein Anstieg des Gesamtkollagengehalts und eine spezifische Zunahme der Kollagene I und IV beobachtet. Darüber hinaus zeigte die Lektinfärbung krankheitsspezifische Unterschiede in der GAG-Zusammensetzung: Der Gehalt an N-Acetylglucosamin-tragenden GAGs und an N-Acetylgalactosamin-tragenden GAGs war in der ECM von LR-MDS erhöht, während die ECM von HR-MDS einen hohen Gehalt an N-Acetylglucosamin, aber nur einen geringen Gehalt an N-Acetylgalactosamin-GAGs aufwies. Die Veränderungen bei den N-Acetyl-Galactosamin- und N-Acetyl-Glucosamin-GAGs wurden durch Chondroitinsulfat (CS)-Immunfärbung bzw. Hyaluronsäure (HA) ELISA weiter bestätigt. Eine Elektrophoretische Analyse zeigte das Vorhandensein von niedermolekularem (LMW)-HA in einer der von LR-MDS-MSCs stammenden ECM. Darüber hinaus zeigte die Stimulierung von mononuklearen Zellen mit LMW-HA einen Anstieg der Genexpression von pro-inflammatorischen Zytokinen wie IL6, was auf eine Rolle von LMW-HA im entzündlichen Zustand des Knochenmarks von LR-MDS hindeutet. Darüber hinaus wies die ECM von LR- und von HR-MDS, eine verminderte Fähigkeit, hämatopoetische Stammvorläuferzellen (HSPCs) zu unterstützen, auf. Dies zeigte sich in einem Verlust sowohl der polaren Morphologie von HSPCs als auch des anschließenden koloniebildenden Potenzials selbiger. Darüber hinaus wurde die verringerte Steifigkeit der ECM von MDS-MSCs, die nach der AZA-Therapie aus den Patienten isoliert wurden, umgekehrt. In ähnlicher Weise führte die direkte Exposition von kultivierten MDS-MSCs mit AZA zu einer entsprechenden Erhöhung der Steifigkeit der ECM. Diese war jedoch geringer als bei den nach der AZA-Therapie isolierten MDS-MSCs. Die Verringerung des Kollagengehalts der ECM wurde nur in der in vivo mit AZA behandelten MSC-ECM beobachtet, nicht aber in den in vitro mit AZA behandelten Proben. Dies deutet darauf hin, dass die AZA-vermittelte Wiederherstellung der ECM-Steifigkeit ein Ergebnis der indirekten Wirkung von AZA im Knochenmark ist und eventuell vom MDS-Klon ausgeht. Interessanterweise wurde bei einigen ECMs von MDS-Patienten nach der AZA-Therapie eine Verbesserung der Koloniebildung hierauf- kultivierter HSPCs beobachtet. Darüber hinaus deutet eine polarisierte Morphologie von HSPCs, die auf der ECM von in vivo und in vitro AZA-behandelten MDS-MSCs vorkultiviert wurden, auf eine teilweise Wiederherstellung des Verhaltens von HSPCs auf der AZA-behandelten MDS-ECM hin. Zusammenfassend lässt sich sagen, dass diese Studie Veränderungen in der Struktur, im Kollagengehalt und in der GAG-Zusammensetzung zwischen der ECM von MDS-MSCs und der ECM von gesunden MSCs nachgewiesen hat. Dies ist auch eine der ersten Studien, die einen Einfluss der aus MDS-MSCs stammenden ECM auf die Morphologie und Funktion von HSPCs zeigt. Dies weist auf die Rolle der ECM bei der Entstehung hämatologischer Malignome hin. Darüber hinaus deutet die teilweise Korrektur des MDS-ECM-Phänotyps nach einer in vivo AZA-Behandlung darauf hin, dass die ECM selbst ein potenzielles therapeutisches Ziel sein könnte. Ein besseres und tieferes Verständnis des Beitrags der ECM zu MDS-Krankheitsprozessen wird es uns daher ermöglichen, neue therapeutische Ziele zu finden, um das Ansprechen auf Medikamente verbessern zu können
15

Isolamento e caracterização das células mesenquimais derivadas da membrana amniótica dos gatos domésticos / Isolation and characterization of Mesenchymal cells from cat amniotic membrane

Vidane, Atanásio Serafim 10 August 2012 (has links)
As células tronco mesenquimais derivadas do âmnio (AMSCs) são células multipotentes com alto potencial para se diferenciar em múltiplas linhagens. Podem ser isoladas sem recurso a procedimentos invasivos e usadas sem levantar quaisquer implicações éticas. O presente estudo visa isolar e caracterizar as células mesenquimais progenitoras da membrana amniótica de gatos domésticos para futura aplicação em terapia celular. As células foram isoladas de quatro membranas fetais, coletadas durante as campanhas rotineiras de castração em gatas no último terço de gestação, após anestesia geral. A porção dorsal do âmnio foi separada mecanicamente, lavada com PBS e submetida à digestão com colagenase. As células coletadas foram propagadas em cultivo (DMEN-F12/-MEM) e criopreservadas em várias passagens enquanto se efetuava a avaliação da cinética de crescimento e das características morfológicas. Em cultivo, as AMSCs demonstraram aderência à placa e uma morfologia similar a dos fibroblastos. A análise imunofenotípica revelou presença de marcadores específicos de MSCs CD73 e CD90 e ausência de marcadores hematopoiéticos CD34, CD45 e CD79 sugerindo a presença de células mesenquimais multipotentes na membrana amniótica de gatos domésticos. Em condições apropriadas, estas células diferenciaram-se em linhagens específicas osteogênica e adipogênica. Entretanto, após inoculação em camundongos imunodeficientes não foi registrado formação de teratomas. Estes achados sugerem que o âmnio de gatos domésticos pode ser considerado uma importante fonte de MSCs com maior atração para medicina regenerativa. / The amnion derived mesenchymal stem cells (AMSCs) are multipotent cells with a high ability to differentiate into multiple lineages. They can be obtained by non-invasive methods and therefore are exempt from the normal ethical problems involving stem cell use. The aim of this study was to isolate and characterize the progenitor mesenchymal cells from the cat amniotic membrane for future application in cell therapy. The cells were isolated from four fetal membranes collected after a routine ovarian hysterectomy process from cats in their third gestational trimester, under general anesthesia. The dorsal portion of amnion was mechanically separated, washed with PBS and subjected to collagenase digestion. The isolated cells were propagated in culture media (DMEMF12 or -MEM) and frozen in various passages while the growing kinetics and cell morphology were analyzed. In culture medium, AMSCs were adherent to the plastic culture dish and had a morphology similar to fibroblasts. Immunophenotyping assays showed the presence of MSCs specific markers CD73 and CD90 and absence of hematopoietic markers CD34, CD45 and CD79 suggesting the presence of multipotent mesenchymal cells in the cat amniotic membrane. Under appropriate conditions, these cells differentiated into osteogenic and adipogenic cell lineages. Moreover, after injection into immunodeficient mice, no tumors were generated. These findings suggest that the cat amniotic membrane can be considered an important and useful source of MSCs for regenerative medicine.
16

Cultura de células osteogênicas primárias a partir de osso de baixa densidade e análise do reparo ósseo periimplantar em ratas osteoporóticas em função da texturização de superfície por meio da oxidação por plasma eletrolítico /

Silva, William Phillip Pereira da. January 2019 (has links)
Orientador: Leonardo Perez Faverani / Coorientadora: Roberta Okamoto / Banca: Daniela Ponzoni / Banca: Ellen Cristina Gaetti Jardim / Resumo: O objetivo deste estudo foi avaliar um novo método de texturização por PEO com incorporação de Ca e P na superfície do Ti-6Al-4V em ossos de baixa densidade, por meio de avaliação in vitro, ex-in vivo e in vivo, em função de parâmetros topográficos e reparacionais. 57 ratas Wistar (Rattus novergicus), sendo 38 ratas com 6 meses de idade (Grupos OXV - submetidas à ovariectomia e SHAM - cirurgia fictícia) e 19 ratas senis (18 meses de idade: Grupo SENIL), foram divididas para realização do estudo ex-in vivo (n=9) e in vivo (n=48). Os grupos para análise ex-in vivo foram submetidos à eutanásia e os fêmures foram removidos e transportados em meio de cultura contendo meio essencial mínimo modificação alfa (α- MEM) suplementado com 500 µg/mL de gentamicina e 3 µg/mL de fungisona. As células-tronco mesenquimais de medula óssea (CTMs-MO) dos fêmures, foram isoladas e cultivadas em meio de crescimento para manterem-se como CTMs. Após alcançar a subconfluência, as células foram cultivadas em 3 superfícies de discos de Ti-6Al-4V, grupo CONTROLE (superfície usinada) grupo AC (superfície tratada por Ataque Ácido e Jateamento) e grupo PEO (superfície tratada por Oxidação de Plasma Eletrolítico com associação de Cálcio e Fosforo). Para avaliação das respostas celulares foram realizados ensaios de viabilidade celular, expressão gênica de marcadores osteoblásticos, imunolocalização de sialoproteina óssea (BSP) e osteopontina (OPN), atividade da fosfatase alcalina (ALP) e formação de matriz mi... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to evaluate a new PEO texturing method with Ca and P incorporation on the Ti-6Al-4V surface in low bone density, by means of in vitro, ex vivo and in vivo evaluation through topographic and repairment parameters. 57 Wistar rats (Rattus novergicus), being 38 at 6 months of age (OXV Groups - submitted to ovariectomy and SHAM surgery) and 19 senile rats (18 months of age: SENIL Group) were divided into three subgroups: ex-in vivo (n = 9) and in vivo (n = 48). The Groups for ex-in vivo analysis were euthanized and femurs were removed and transported in culture medium containing minimal alpha modification (α- MEM) medium supplemented with 500 μg / ml gentamicin and 3 μg / ml fungizone. The mesenchymal stem cells from bone marrow (MSC-M) of the femur were isolated and cultured in growth medium to remain as MSCs. After reaching the subconfluence, the cells were grown on 3 surfaces of Ti-6Al-4V discs, CONTROL group (machined surface) group AC (surface treated by etched-acid) and PEO group (surface treated by Electrolytic Plasma Oxidation with the association of Calcium and Phosphorus). Cell viability assays, gene expression of osteoblastic markers, bone sialoprotein (BSP) and osteopontin (OPN), alkaline phosphatase (ALP) activity, and mineralized matrix formation were performed to evaluate cellular responses. Data were submitted to ANOVA 1 factor test or Kruskal-Wallis test (P <0.05). In the groups for the in vivo study, after 90 days, an implant was i... (Complete abstract click electronic access below) / Mestre
17

Implante autólogo de células mesenquimais no tratamento de tendinites induzidas em eqüinos: avaliação clínica, ultrasonográfica, histopatológica e imunoistoquímica

Barreira, Anna Paula Balesdent [UNESP] January 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2005Bitstream added on 2014-06-13T20:27:19Z : No. of bitstreams: 1 barreira_apb_dr_botfmvz.pdf: 3081642 bytes, checksum: 31a0f6fc8ca00d6226b303ef5a047356 (MD5) / Universidade Estadual Paulista (UNESP) / A lesão do tendão do músculo flexor digital superficial (TFDS) é uma importante causa de claudicação em eqüinos, com prevalência de 13 a 30%, de acordo com a atividade eqüestre. Sua instalação pode comprometer a carreira do potro com recidivas ou causar o afastamento das corridas. Além disto, determina longos períodos de recuperação, com prejuízo à função tendínea. Os tratamentos propostos são diversos, mas efeitos como melhora da qualidade ou rapidez da cicatrização não são confirmados por estudos controlados. A terapia intralesional com fatores de crescimento (TGF-ß e IGF- 1), assim como a terapia com choques extracorpóreos vêm mostrando resultados promissores. Recentemente, os avanços médicos têm demonstrado crescente interesse na utilização das células-tronco em terapia de doenças degenerativas e também em cicatrização lenta ou ineficaz. Este estudo teve como objetivo avaliar os efeitos do implante autólogo de células mesenquimais de medula óssea na cicatrização tendínea, comparando tendões tratados com tendões do grupo controle. Foi induzida lesão do TFDS de ambos os membros anteriores de seis eqüinos, seguida por implante autólogo em apenas um membro de cada animal. Os animais foram avaliados por parâmetros clínicos e ultra-sonográficos e após biópsia realizada ao 48o dia do experimento, foram verificadas características histopatológicas e imunoistoquímicas. Resultados como aumento do infiltrado inflamatório celular, abundância da matriz, diminuição da necrose, discreto aumento no índice de proliferação celular (Ki- 67, clone MIB1) e menor imunomarcação do TGF-ß1 caracterizam a aceleração do reparo tendíneo no grupo tratado. Estudos aprofundados devem ser desenvolvidos com o objetivo de definir a influência do tratamento em fase posterior do reparo. Conclui-se, então,... / The superficial digital flexor tendonitis (SDFT) is an important cause of lameness in horses with incidence from 13 to 30% depending of the exercise modality. This injury can occur in yearlings and compromise its carrier by reinjury or even the impossibility of return to athletic life. Although long periods of rest are necessary to tendon repair, there is an elasticity loss in the tendon. As current treatment regimes have only marginal effects there is interest in researching therapies that influence the quality or the duration of tendon repair. Intralesional therapy with growth factors (TGFß1 e IGF-1) and radial shock wave therapy have been presenting promising results. Recently, medical interest has been directed to the stem cells therapy of degenerative diseases and cases of deficient healing process. This study aims to evaluate the influence of autologous mesenchymal stem cells from bone marrow in tendon healing, comparing treated and none treated tendons. Induced collagen lesions were in both forelimbs TFDS from six horses, followed by autologous implant in one forelimb from each animal. The horses were evaluated by clinical, ultrasonographic, histophatologic and imunohistochemistry parameters. Tendon biopsies were done at day 48. Results such as high inflammation cells infiltration and synthesis of extracellular matrix, few necrosis areas, discrete increase in cellular proliferation (Ki-67) and low immunoreactivity to TGFß1 found in treatment group suggested the acceleration of tendon repair in this group. Further studies should be developed in order to verify the influence of this treatment on later phase of tendon repair. Overall, after analysis of results, we conclude that cellular therapy with mesenchymal stem cells have accelerate tendon repair at 48 days after treatment.
18

Modélisation du syndrome d'Andersen dans les cellules souches pluripotentes induites : implication du canal potassique Kir2.1 dans la morphogenèse osseuse / Modeling Andersen's syndrome using induced Pluripotent Stem cells : implication of Kir2.1 potassium channel in bone morphogenesis

Pini, Jonathan 13 July 2016 (has links)
Le syndrome d’Andersen est une maladie rare et associée à la perte de fonction du canal potassique Kir2.1. Afin d’étudier sa physiopathologie, nous avons généré et caractérisé des cellules souches pluripotentes induites (iPS) contrôle et Andersen. Nous avons ensuite différencié ces cellules iPS en cellules souches mésenchymateuse (MSC). Les cellules MSC de patients présentent une capacité de différenciation en ostéoblastes et en chondrocytes diminuée par rapport aux cellules contrôle. En effet, la production de matrice extracellulaire et l'expression des master gènes des différenciations osseuses et cartilagineuses, est réduite chez les patients. Ces travaux de thèse montrent que le canal Kir2.1 est essentiel au développement osseux. Les défauts de différentiation observés pourraient expliquer les dysmorphies associées avec le syndrome d’Andersen. / Andersen's syndrome is a rare disorder associated with a Kir2.1 potassium channel loss of fuction. To study the pathophysiology, we have generated and characterized induced Pluripotent Stem cells (iPS) from control and patient cells. We have then differentiated those iPS cells into mesenchymal stem cells (MSC). Patient's MSc have a lower osteoblastic and chondrogenic differnciation ability compared to control cells. Indeed, extracellular matrix production and master gene expression of osteoblastic and chondrogenic differenciation are reduced in patient’s cells. Alltogether, these results shown that Kir2.1 channel is required for bone developement. The differenciation defects saw in patient cells could explain the Andersen's syndrome associated dysmorphies.
19

Regulação das células mesenquimais da matriz do cordão umbilical canino durante a osteogênese /

Gonzaga, João Paulo Ignácio January 2017 (has links)
Orientador: Teresa Cristina Cardoso da Silva / Banca: Roberto Gameiro de Carvalho / Banca: Andréa Fontes Garcia / Resumo: As células mesenquimais derivadas da geleia de Wharton isoladas da matriz do cordão umbilical canino tem sido sugeridas como uma fonte promissora de MSCs para serem usadas nas aplicações clínicas em ciência veterinária, como uma ferramenta potencialmente efetiva na regeneração óssea. MicroRNA (miARN) é um regulador pós-transcricional da expressão gênica em várias condições fisiológicas, incluindo a osteogênese. Neste estudo, as MSCs caninos (cMSCs) isoladas da geléia de Wharton foram induzidos a osteogênese e a transcrição de miR-106b foi avaliada em 0, 7, 14 e 21 dias após a indução. Em outro experimento, as cMSC foram transfectadas com um imitador de miR106b e um inibidor e induzidos a osteogênese. Morfologicamente, cMSCs transfectadas com um inibidor de miR-106b produziram células semelhantes a osteócitos quando comparadas às mesmas células transfectadas com o mímico de miR-106b. cMSCs apresentaram transcrição de miR-106b após 7 dias de osteoindução em um nível baixo em comparação com o controle positivo, enquanto as células transfectadas com o mímico de miR-106b mostraram que o miR-106b deveria ser regulado positivamente. Após a inibição da expressão de miR-106b em cMSCs osteoinduzidas, a atividade da fosfatase alcalina (ALP) foi aumentada. A transcrição do mRNA de osteocalcina, osteopontina e RUNX2 foi regulada positivamente aos 21 dias após a osteoindução, após a inibição de miR106b. Esses achados, pela primeira vez, mostraram que a expressão de miR106b regula negativam... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Wharton's jelly derived-MSCs isolated from canine umbilical cord matrix have been suggested as a promising source of MSCs to be used for clinical applications in veterinary science, as a potentially effective tool in bone regeneration. MicroRNA (miRNA) is a post-transcriptional regulator of gene expression in several physiological conditions, including osteogenesis In this study, canine MSCs (cMSCs) isolated from Wharton's jelly were induced to osteogenesis and miR-106b transcription was measured at 0, 7, 14 and 21 days following induction. In another experiment, cMSCs were transfected with a miR106b mimic and an inhibitor and induced to osteogenesis. Morphologically, cMSCs transfected with an inhibitor of miR-106b appeared as osteocyte-like cells when compared to the same cells transfected with the mimic of miR-106b. cMSCs showed miR-106b transcription after 7 days of osteoinduction was at a low level compared to the positive control, whereas transfected cells with the miR-106b mimic showed miR-106b to be upregulated. After inhibition of miR-106b expression in osteoinduced cMSCs, alkaline phosphatase (ALP) activity was increased. Osteocalcin, osteopontin and RUNX2 mRNA transcription were upregulated at 21 days after osteoinduction following miR-106b inhibition. These findings have, for the first time, shown that the expression of miR-106b negatively regulates osteogenesis in canine MSCs derived from Wharton's jelly and seems to interfere with cell differentiation. / Mestre
20

Regulação das células mesenquimais da matriz do cordão umbilical canino durante a osteogênese / Regulation of mesenchymal cells of the canine umbilical cord matrix during osteogenesis

Gonzaga, João Paulo Ignácio [UNESP] 07 August 2017 (has links)
Submitted by João Paulo Ignacio Gonzaga null (jp-ignaciogonzaga@hotmail.com) on 2017-08-30T00:35:08Z No. of bitstreams: 2 Dissertação João Paulo 2017.pdf: 958263 bytes, checksum: 7ef6cdf74470df5e3235cc2a1783d5ea (MD5) Dissertação João Paulo 2017.pdf: 958263 bytes, checksum: 7ef6cdf74470df5e3235cc2a1783d5ea (MD5) / Rejected by Luiz Galeffi (luizgaleffi@gmail.com), reason: Solicitamos que realize uma nova submissão seguindo a orientação abaixo: O arquivo submetido está sem a ficha catalográfica e sem o certificado de aprovação. A versão submetida por você é considerada a versão final da dissertação/tese, portanto não poderá ocorrer qualquer alteração em seu conteúdo após a aprovação. Corrija esta informação e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2017-08-30T17:26:52Z (GMT) / Submitted by João Paulo Ignacio Gonzaga null (jp-ignaciogonzaga@hotmail.com) on 2017-08-31T18:19:05Z No. of bitstreams: 1 dissertação João Paulo 2017 Pronta.pdf: 1042134 bytes, checksum: 67115cf2cf469d731be2911085bc6b7a (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-09-01T13:24:56Z (GMT) No. of bitstreams: 1 gonzaga_jpi_me_araca.pdf: 1042134 bytes, checksum: 67115cf2cf469d731be2911085bc6b7a (MD5) / Made available in DSpace on 2017-09-01T13:24:56Z (GMT). No. of bitstreams: 1 gonzaga_jpi_me_araca.pdf: 1042134 bytes, checksum: 67115cf2cf469d731be2911085bc6b7a (MD5) Previous issue date: 2017-08-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As células mesenquimais derivadas da geleia de Wharton isoladas da matriz do cordão umbilical canino tem sido sugeridas como uma fonte promissora de MSCs para serem usadas nas aplicações clínicas em ciência veterinária, como uma ferramenta potencialmente efetiva na regeneração óssea. MicroRNA (miARN) é um regulador pós-transcricional da expressão gênica em várias condições fisiológicas, incluindo a osteogênese. Neste estudo, as MSCs caninos (cMSCs) isoladas da geléia de Wharton foram induzidos a osteogênese e a transcrição de miR-106b foi avaliada em 0, 7, 14 e 21 dias após a indução. Em outro experimento, as cMSC foram transfectadas com um imitador de miR106b e um inibidor e induzidos a osteogênese. Morfologicamente, cMSCs transfectadas com um inibidor de miR-106b produziram células semelhantes a osteócitos quando comparadas às mesmas células transfectadas com o mímico de miR-106b. cMSCs apresentaram transcrição de miR-106b após 7 dias de osteoindução em um nível baixo em comparação com o controle positivo, enquanto as células transfectadas com o mímico de miR-106b mostraram que o miR-106b deveria ser regulado positivamente. Após a inibição da expressão de miR-106b em cMSCs osteoinduzidas, a atividade da fosfatase alcalina (ALP) foi aumentada. A transcrição do mRNA de osteocalcina, osteopontina e RUNX2 foi regulada positivamente aos 21 dias após a osteoindução, após a inibição de miR106b. Esses achados, pela primeira vez, mostraram que a expressão de miR106b regula negativamente a osteogênese em MSCs caninos derivados da geléia de Wharton e parece interferir na diferenciação celular. / Wharton`s jelly derived-MSCs isolated from canine umbilical cord matrix have been suggested as a promising source of MSCs to be used for clinical applications in veterinary science, as a potentially effective tool in bone regeneration. MicroRNA (miRNA) is a post-transcriptional regulator of gene expression in several physiological conditions, including osteogenesis In this study, canine MSCs (cMSCs) isolated from Wharton´s jelly were induced to osteogenesis and miR-106b transcription was measured at 0, 7, 14 and 21 days following induction. In another experiment, cMSCs were transfected with a miR106b mimic and an inhibitor and induced to osteogenesis. Morphologically, cMSCs transfected with an inhibitor of miR-106b appeared as osteocyte-like cells when compared to the same cells transfected with the mimic of miR-106b. cMSCs showed miR-106b transcription after 7 days of osteoinduction was at a low level compared to the positive control, whereas transfected cells with the miR-106b mimic showed miR-106b to be upregulated. After inhibition of miR-106b expression in osteoinduced cMSCs, alkaline phosphatase (ALP) activity was increased. Osteocalcin, osteopontin and RUNX2 mRNA transcription were upregulated at 21 days after osteoinduction following miR-106b inhibition. These findings have, for the first time, shown that the expression of miR-106b negatively regulates osteogenesis in canine MSCs derived from Wharton´s jelly and seems to interfere with cell differentiation.

Page generated in 0.3615 seconds