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‣ Stem cells in endometrium and their role in the pathogenesis of endometriosis

FIGUEIRA, Paula Gabriela Marin; ABRAO, Mauricio Simoes; KRIKUN, Graciela; TAYLOR, Hugh
Fonte: BLACKWELL SCIENCE PUBL Publicador: BLACKWELL SCIENCE PUBL
Tipo: Artigo de Revista Científica
Português
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The human endometrium is a dynamic tissue that undergoes cycles of growth and regression with each menstrual cycle. Adult progenitor stem cells are likely responsible for this remarkable regenerative capacity; these same progenitor stem cells may also have an enhanced capacity to generate endometriosis if shed in a retrograde fashion. The progenitor stem cells reside in the uterus; however, less-committed mesenchymal stem cells may also travel from other tissues such as bone marrow to repopulate the progenitor population. Mesenchymal stem cells are also involved in the pathogenesis of endometriosis and may be the principle source of endometriosis outside of the peritoneal cavity when they differentiate into endometriosis in ectopic locations. Finally, besides progenitor stem cells, recent publications have identified multipotent stem cells in the endometrium. These multipotent stem cells are a readily available source of cells that are useful in tissue engineering and regenerative medicine. Endometrial stem cells have been used to generate chondrocytes, myocytes, neurons, and adiposites in vitro as well as to replace dopaminergic neurons in a murine model of Parkinson`s disease.; NIH[U54HD052668]

‣ Avaliação da osteogênese em defeitos ósseos com utilização da engenharia tecidual óssea: uma comparação entre osso autógeno, substituto ósseo e células-tronco mesenquimais; Evaluation of osteogenesis in bone defects using bone tissue engineered: a comparison among autogenous bone, bone substitute and mesenchymal stem cells

Prata, Celina Antonio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 30/08/2010 Português
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O tecido ósseo possui potencial regenerativo e capacidade em restaurar completamente sua estrutura e função original. Há situações em que o organismo não consegue por si só, a reparação desejada dos defeitos ósseos. Vários métodos são propostos para a reparação de defeitos ósseos, entre eles, o uso de diferentes tipos de enxertos os quais demonstram capacidade em promover a formação óssea. Por muitos anos o osso autógeno foi considerado a referência padrão como enxerto ósseo, devido as suas vantagens biológicas e potencial osteogênico. Entretanto, por este material apresentar limitações, estimulou-se a pesquisa para um substituto ósseo ideal para o enxerto ósseo autogênico. O advento de um novo biomaterial xenogênico, como o osso bovino, que se comporta como promotor de reparação e é portador de fatores de indução óssea parece representar o futuro da reconstrução de defeitos ósseos. Mas pelo pequeno potencial de regeneração óssea produzida pelos enxertos alógenos e xenógenos, os pesquisadores tem utilizado a bioengenharia tecidual óssea para reconstrução de defeitos ósseos. Diante destas informações, este estudo teve como objetivo quantificar histomorfometricamente a reparação óssea após o enxerto de uma associação de osso autógeno e/ou osso bovino composto (Gen-Mix) associados a células- tronco mesenquimais em defeitos ósseos produzidos pela extração dental de ratos. 108 ratos foram separados em 6 grupos : Controle (c) - o defeito ósseo foi preenchido só por sangue; Osso autógeno (oa) - o defeito ósseo foi preenchido por sangue e osso autógeno; Gen-Mix (G-mix) o defeito ósseo foi preenchido por osso bovino composto (osso medular e cortical)...

‣ Produção e uso da proteína de fusão VP22.Pax4 na diferenciação de células-tronco em células produtoras de insulina; Production and use of the VP22.Pax4 fusion protein for stem cells differentiation into insulin-producing cells

Gabanyi, Ilana
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 12/11/2010 Português
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O Diabetes Mellitus tipo I (DM1) é causado pela destruição auto-imune das células β pancreáticas, encontradas na porção endócrina do pâncreas, constituída pelas ilhotas pancreáticas. As células β são responsáveis pela produção e liberação de insulina, um hormônio que promove a internalização da glicose pelas células. Junto com outros hormônios, a insulina é um dos principais reguladores do nível de glicose sanguinea (glicemia). Uma das terapias utilizadas para o tratamento do DM1 é o transplante de ilhotas pancreáticas. Entretanto, um dos maiores problemas em relação a esta terapia é a falta de massa celular adequada para ser infundida no paciente. Uma tentativa para solucionar este problema, é o desenvolvimento de fontes alternativas de células produtoras de insulina, como as células-tronco, que possuem a capacidade de se diferenciarem em diversos tipos de células, inclusive nas produtoras de insulina. Pax4 é um dos fatores de transcrição responsáveis pela diferenciação de células β , sendo essencial para o apropriado desenvolvimento e maturação destas, constitui um bom candidato para induzir a diferenciação de células-tronco em células produtoras de insulina in vitro. Para introduzir o Pax4 nas células-tronco...

‣ Comparação entre fontes de células-tronco mesenquimais na indução à regeneração óssea; Comparison of mesenchymal stem cells from different sources in inducing bone formation

Almada, Bruno Vinicius Pimenta de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 08/08/2013 Português
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A regeneração óssea é um processo fisiológico que promove a neoformação de tecido ósseo saudável e funcional com características idênticas antes da lesão. Entretanto, frente a defeitos críticos, o osso é incapaz de se regenerar espontaneamente. Diante destas deficiências, a bioengenharia de tecidos ósseos (BTO) é uma opção promissora para a regeneração deste tipo de defeito. A maioria das abordagens de BTO utiliza as células-tronco mesenquimais da medula óssea (BMSC), porém, a coleta de BMSC dos pacientes é um processo bastante invasivo e doloroso. Por estas desvantagens, a busca por abordagens acessíveis e menos invasivas de novas fontes de células-tronco (CT) se tornou necessária. Neste contexto, as células-tronco de polpa de dentes decíduos (SHED) foram identificadas e sua aplicação na BTO, desde então, vem sendo amplamente estudada devido ao seu potencial osteogênico e por se tratar de uma fonte não invasiva. A obtenção de células-tronco do músculo orbicular do lábio (OOMDSC) também não causa dor adicional aos indivíduos, pois os fragmentos deste tecido são rotineiramente descartados durante as cirurgias de reconstrução do lábio. No presente trabalho investigamos o potencial de diferenciação osteoblástico in vitro e in vivo das OOMDSC e comparamos com as SHED...

‣ Células-tronco mesenquimais: isolamento e caracterização de populações derivadas de alvéolo dental humano e identificação e caracterização de populações de polpas dentais de camundongos; Mesenchymal stem cells: Isolation and characterization of populations derived from human dental alveolus and identification and characterization of populations from mouse dental pulp

Luiz, Lucyene Miguita
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 29/11/2013 Português
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Há um grande interesse no estudo de células-tronco em função de sua capacidade de auto-renovação e plasticidade. Estas características capacitam as células-tronco a produzirem células de diferentes linhagens que participam ativamente do processo de homeostase, da resposta à injúria e da regeneração e reparação tecidual. A polpa dental é o tecido mais estudado na Odontologia em relação a células-tronco, mas diversos estudos já mostraram a presença dessas células também na região periodontal. É importante salientar, que dependendo de sua origem, as células-tronco apresentam comportamentos diversos, especialmente no que tange ao transplante in vivo. Além disso, os microambientes onde as células-tronco residem (nichos), têm um papel fundamental no comportamento das mesmas, pois controlam aspectos essenciais como o estado de indiferenciação e a auto-renovação. Esse projeto de pesquisa teve como objetivos duas análises distintas. Na primeira, verificar se existem células-tronco mesenquimais derivadas da curetagem do alvéolo dental humano após extrações dentais. Na segunda, analisar o nicho de células-tronco nas polpas dentais de camundongos. Em comum, as duas análises se basearam no uso de marcadores previamente utilizados na literatura para o estudo de células-tronco. Como não existem marcadores únicos e específicos para a identificação dessas células...

‣ Estudo da interação das células-tronco mesenquimais e linfócitos no modelo da doença do enxerto contra hospedeiro; Study of mesenchymal stem cells and lymphocytes interaction in graft versus host disease model

Normanton, Marília
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/07/2014 Português
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Uma das principais complicações inerentes ao transplante de células-tronco hematopoiéticas é a doença do enxerto contra hospedeiro (DECH), que se trata da resposta imunológica contra os tecidos do receptor pelas células T do doador contidas no transplante. Este quadro é responsável por 15-30% das mortes que ocorrem após o transplante de células-tronco hematopoiéticas alogênicas. Apesar dos recentes avanços para reduzir a incidência de DECH através de alternância de regimes profiláticos reduzindo a intensidade do condicionamento, são poucos os tratamentos efetivos. Recentemente, o potencial imunomodulador das células-tronco mesenquimais tornou-se o foco de vários estudos. Alguns autores descreveram a atuação destas células na redução da resposta imunológica através da inibição da proliferação de células T, representando um novo potencial terapêutico para DECH. Mediante esse conhecimento, investigamos o papel das células-tronco mesenquimais na proliferação, apoptose e na produção de citocinas por linfócitos T. Nossos resultados mostraram que a presença de células-tronco mesenquimais nas culturas regulam negativamente a proliferação de linfócitos T estimulados de forma independente de contato e a apoptose de forma parcialmente dependente de contato. Observamos também que linfócitos T virgens em diferenciação para Th17 na presença de células-tronco mesenquimais apresentam redução na capacidade de produzir duas importantes citocinas efetoras implicadas na DECH...

‣ In vivo evaluation of the potencial of mesenchymal stem cells (MSCs) from wharton jelly (WJ) to improve the biocompatibility of poly(vinyl) alcohol hydrogel (PVA) membranes in animal model (sheep).

Alexandre, Nuno; Lopes, Ascensão; Rodrigues, Miguel; Amorim, Irina; Pereira, Tiaho; Gärtner, Andrea; Maurício, Ana Colette; Santos, José Domingos; Luís, Ana Lúcia
Fonte: Sociedade Portuguesa de Células Estaminais e Terapias Celulares - 8th International Meeting of the Portuguese Society for Stem Cells and Cell Therapies Publicador: Sociedade Portuguesa de Células Estaminais e Terapias Celulares - 8th International Meeting of the Portuguese Society for Stem Cells and Cell Therapies
Tipo: Aula
Português
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758.9201%
Introduction: The use of cellular systems for improving biointegration of medical devices is a current trend of tissue engineering. The biocompatibility is a key aspect that can influence the performance of medical devices, for that reason inflammatory and foreign body reaction must be evaluated in pre-clinical studies. MSCs can modify the interaction of biomaterials with tissues by several mechanisms through the immunomodulatory effects of these cells allowing a faster biointegration avoiding an exuberant local inflammatory reaction (Martino et al.). These immunomodulatory changes are linked to the suppression of inflammatory cytokines and to the induction of T cells with regulatory or suppressive phenotypes. For this reason, we have decided to evaluate the association of MSCs isolated from the umbilical cord WJ with PVA membranes in order to use this biomaterial in future as a scaffold for vascular reconstruction. Materials and Methods: PVA membranes were produced by a freeze/thawed method with a diameter of 15 mm and 3 mm thickness. In order to coat PVA membranes with MSCs they were seeded with a cell density of 104cells/cm2 for 4 days. For the in vivo evaluation, 24 adult female sheep were divided in 4 groups of 6 animals each. In group 1...

‣ Characterization of human adipose-derived stem cells and expression of chondrogenic genes during induction of cartilage differentiation

Hamid,Adila A; Idrus,Ruszymah Bt Hj; Saim,Aminuddin Bin; Sathappan,Somasumdaram; Chua,Kien-Hui
Fonte: Faculdade de Medicina / USP Publicador: Faculdade de Medicina / USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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OBJECTIVES: Understanding the changes in chondrogenic gene expression that are involved in the differentiation of human adipose-derived stem cells to chondrogenic cells is important prior to using this approach for cartilage repair. The aims of the study were to characterize human adipose-derived stem cells and to examine chondrogenic gene expression after one, two, and three weeks of induction. MATERIALS AND METHODS: Human adipose-derived stem cells at passage 4 were evaluated by flow cytometry to examine the expression of surface markers. These adipose-derived stem cells were tested for adipogenic and osteogenic differentiation capacity. Ribonucleic acid was extracted from the cells for quantitative polymerase chain reaction analysis to determine the expression levels of chondrogenic genes after chondrogenic induction. RESULTS: Human adipose-derived stem cells were strongly positive for the mesenchymal markers CD90, CD73, CD44, CD9, and histocompatibility antigen and successfully differentiated into adipogenic and osteogenic lineages. The human adipose-derived stem cells aggregated and formed a dense matrix after chondrogenic induction. The expression of chondrogenic genes (collagen type II, aggrecan core protein, collagen type XI...

‣ Fibroblast Growth Factor Type 2 Signaling Is Critical for DNA Repair in Human Keratinocyte Stem Cells

Harfouche, Ghida; Vaigot, Pierre; Rachidi, Walid; Rigaud, Odile; Moratille, Sandra; Marie, Mélanie; Lemaitre, Gilles; Fortunel, Nicolas O; Martin, Michèle T
Fonte: Wiley Subscription Services, Inc., A Wiley Company Publicador: Wiley Subscription Services, Inc., A Wiley Company
Tipo: Artigo de Revista Científica
Publicado em /09/2010 Português
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Tissue stem cells must be endowed with superior maintenance and repair systems to ensure genomic stability over multiple generations, which would be less necessary in more differentiated cells. We previously reported that human keratinocyte stem cells were more resistant to ionizing radiation toxicity than their direct progeny, the keratinocyte progenitor cells. In the present study we addressed the mechanisms underlying this difference. Investigations of DNA repair showed that both single and double DNA strand breaks were repaired more rapidly and more efficiently in stem cells than in progenitors. As cell signaling is a key regulatory step in the management of DNA damage, a gene profiling study was performed. Data revealed that several genes of the fibroblast growth factor type 2 (FGF2) signaling pathway were induced by DNA damage in stem cells and not in progenitors. Furthermore, an increased content of the FGF2 protein was found in irradiated stem cells, both for the secreted and the cellular forms of the protein. To examine the role of endogenous FGF2 in DNA repair, stem cells were exposed to FGF2 pathway inhibitors. Blocking the FGF2 receptor (FGF receptor 1) or the kinase (Ras-mitogen-activated protein kinase 1) resulted in a inhibition of single and double DNA strand-break repair in the keratinocyte stem cells. Moreover...

‣ Defining Molecular Phenotypes of Mesenchymal and hematopoietic Stem Cells derived from Peripheral blood of Acute Lymphocytic Leukemia patients for regenerative stem cell therapy

Potdar, PD; Subedi, RP
Fonte: Journal of Stem cells and Regenerative medicine Publicador: Journal of Stem cells and Regenerative medicine
Tipo: Artigo de Revista Científica
Publicado em 01/04/2011 Português
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Acute Lymphocytic Leukemia (ALL) is a clonal myeloid disorder affecting all age groups, characterized by accumulation of immature blast cells in bone marrow and in peripheral blood. Autologous Bone Marrow Transplantation is a present treatment for cure of ALL patients, which is very expensive, invasive process and may have possibility of transplantation of malignant stem cells to patients. In the present study, we hypothesized to isolate large number of normal Mesenchymal & Hematopoietic stem cells from peripheral blood of ALL patients, which will be further characterized for their normal phenotypes by using specific molecular stem cell markers. This is the first study, which defines the existing phenotypes of isolated MSCs and HSCs from peripheral blood of ALL patients. We have established three cell lines in which two were Mesenchymal stem cells designated as MSCALL and MSCnsALL and one was suspension cell line designated as HSCALL. The HSCALL cell line was developed from the lymphocyte like cells secreted by MSCALL cells. Our study also showed that MSCALL from peripheral blood of ALL patient secreted hematopoietic stem cells in vitro culture. We have characterized all three-cell lines by 14 specific stem cell molecular markers. It was found that both MSC cell lines expressed CD105...

‣ Differentiation of neuron-like cells from mouse parthenogenetic embryonic stem cells☆

Yan, Xingrong; Yang, Yanhong; Liu, Wei; Geng, Wenxin; Du, Huichong; Cui, Jihong; Xie, Xin; Hua, Jinlian; Yu, Shumin; Li, Liwen; Chen, Fulin
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em 05/02/2013 Português
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Parthenogenetic embryonic stem cells have pluripotent differentiation potentials, akin to fertilized embryo-derived embryonic stem cells. The aim of this study was to compare the neuronal differentiation potential of parthenogenetic and fertilized embryo-derived embryonic stem cells. Before differentiation, karyotype analysis was performed, with normal karyotypes detected in both parthenogenetic and fertilized embryo-derived embryonic stem cells. Sex chromosomes were identified as XX. Immunocytochemistry and quantitative real-time PCR detected high expression of the pluripotent gene, Oct4, at both the mRNA and protein levels, indicating pluripotent differentiation potential of the two embryonic stem cell subtypes. Embryonic stem cells were induced with retinoic acid to form embryoid bodies, and then dispersed into single cells. Single cells were differentiated in N2 differentiation medium for 9 days. Immunocytochemistry showed parthenogenetic and fertilized embryo-derived embryonic stem cells both express the neuronal cell markers nestin, βIII-tubulin and myelin basic protein. Quantitative real-time PCR found expression of neurogenesis related genes (Sox-1, Nestin, GABA, Pax6, Zic5 and Pitx1) in both types of embryonic stem cells...

‣ Cancer Stem Cells Converted from Pluripotent Stem Cells and the Cancerous Niche

Kasai, T; Chen, L; Mizutani, AZ; Kudoh, T; Murakami, H; Fu, L; Seno, M
Fonte: Journal of Stem Cells and Regenerative Medicine Publicador: Journal of Stem Cells and Regenerative Medicine
Tipo: Artigo de Revista Científica
Publicado em 30/04/2014 Português
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Nowadays, the cancer stem cells are considered to be significantly responsible for growth, metastasis, invasion and recurrence of all cancer. Cancer stem cells are typically characterized by continuous proliferation and self-renewal as well as by differentiation potential, while stem cells are considered to differentiate into tissue- specific phenotype of mature cells under the influence of micro-environment. Cancer stem cells should be traced to the stem cells under the influence of a micro-environment, which induces malignant tumors. In this review, we propose this micro-environment as a ‘cancerous niche’ and discuss its importance on the formation and maintenance of cancer stem cells with the recent experimental results to establish cancer stem cell models from induced pluripotent stem cells. These models of cancer stem cell will provide the great advantages in cancer research and its therapeutic applications in the future.

‣ Are newborn rat-derived neural stem cells more sensitive to lead neurotoxicity?★

Chan, Yan Ho; Gao, Mingyong; Wu, Wutian
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em 05/03/2013 Português
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668.1003%
Lead ion (Pb2+) has been proven to be a neurotoxin due to its neurotoxicity on mammalian nervous system, especially for the developing brains of juveniles. However, many reported studies involved the negative effects of Pb2+ on adult neural cells of humans or other mammals, only few of which have examined the effects of Pb2+ on neural stem cells. The purpose of this study was to reveal the biological effects of Pb2+ from lead acetate [Pb (CH3COO)2] on viability, proliferation and differentiation of neural stem cells derived from the hippocampus of newborn rats aged 7 days and adult rats aged 90 days, respectively. This study was carried out in three parts. In the first part, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT viability assay) was used to detect the effects of Pb2+ on the cell viability of passage 2 hippocampal neural stem cells after 48-hour exposure to 0–200 μM Pb2+. In the second part, 10 μM bromodeoxyuridine was added into the culture medium of passage 2 hippocampal neural stem cells after 48-hour exposure to 0–200 μM Pb2+, followed by immunocytochemical staining with anti-bromodeoxyuridine to demonstrate the effects of Pb2+ on cell proliferation. In the last part, passage 2 hippocampal neural stem cells were allowed to grow in the differentiation medium with 0–200 μM Pb2+. Immunocytochemical staining with anti-microtubule-associated protein 2 (a neuron marker)...

‣ Similarity on neural stem cells and brain tumor stem cells in transgenic brain tumor mouse models

Qiao, Guanqun; Li, Qingquan; Peng, Gang; Ma, Jun; Fan, Hongwei; Li, Yingbin
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em 05/09/2013 Português
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Although it is believed that glioma is derived from brain tumor stem cells, the source and molecular signal pathways of these cells are still unclear. In this study, we used stable doxycycline-inducible transgenic mouse brain tumor models (c-myc+/SV40Tag+/Tet-on+) to explore the malignant trans-formation potential of neural stem cells by observing the differences of neural stem cells and brain tumor stem cells in the tumor models. Results showed that chromosome instability occurred in brain tumor stem cells. The numbers of cytolysosomes and autophagosomes in brain tumor stem cells and induced neural stem cells were lower and the proliferative activity was obviously stronger than that in normal neural stem cells. Normal neural stem cells could differentiate into glial fibrillary acidic protein-positive and microtubule associated protein-2-positive cells, which were also negative for nestin. However, glial fibrillary acidic protein/nestin, microtubule associated protein-2/nestin, and glial fibrillary acidic protein/microtubule associated protein-2 double-positive cells were found in induced neural stem cells and brain tumor stem cells. Results indicate that induced neural stem cells are similar to brain tumor stem cells, and are possibly the source of brain tumor stem cells.

‣ TRANSCRIPTIONAL LANDSCAPE OF NEURONAL and CANCER STEM CELLS

Miele, Evelina
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
Português
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669.8457%
Tumor mass is composed by heterogeneous cell population including a subset of “cancer stem cells” (CSC). Oncogenic signals foster CSC by transforming tissue stem cells or by reprogramming progenitor/differentiated cells towards stemness. Thus, CSC share features with cancer and stem cells (e.g. self-renewal, hierarchical developmental program leading to differentiated cells, epithelial/mesenchimal transition) and these latter are maintained by the constitutive activation of stemness-promoting signals. CSC could trigger tumor formation, drive to resistance to conventional therapeutics and underlie patients’ relapse. Indeed, stem cell signatures have been associated with poor prognosis in various. This background makes the identification of CSC molecular features mandatory to highlight the survival inner working and to design novel CSC specific therapeutic strategies. Medulloblastoma (MB) is the most common childhood malignant brain tumor and a leading cause of cancerrelated morbidity and mortality. Current multimodal therapies are effective in about 50% of patients but often cause long-term side effects, i.e. developmental, neurological, neuroendocrine and psychosocial deficits (Northcott PA Nature Rev cancer 2012). For many years...

‣ Putative stem cells in regenerating human periodontium

Lin, N.H.; Menicanin, D.; Mrozik, K.; Gronthos, S.; Bartold, P.
Fonte: Blackwell Munksgaard Publicador: Blackwell Munksgaard
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
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BACKGROUND AND OBJECTIVE: Human postnatal stem cells have been identified in periodontal ligament, with the potential to regenerate the periodontium in vivo. However, it is unclear if periodontal ligament stem cells are present in regenerating periodontal tissues. The aim of this study was to identify and localize putative stem cells in block biopsies and explant cultures of regenerating human periodontal tissues. MATERIAL AND METHODS: Guided tissue regeneration was carried out on the molars of three human volunteers. After 6 wk, the teeth with the surrounding regenerating tissues and bone were surgically removed and processed for immunohistochemistry. The mesenchymal stem cell-associated markers STRO-1, CD146 and CD44 were used to identify putative stem cells. Cell cultures established from regenerating tissue explants were analysed by flow cytometry to assess the expression of these markers. Mineralization, calcium concentration and adipogenic potential of regenerating tissue cells were assessed and compared with periodontal ligament stem cells, bone marrow stromal stem cells and gingival fibroblasts. RESULTS: STRO-1(+), CD44(+) and CD146(+) cells were identified in the regenerating tissues. They were found mainly in the paravascular and extravascular regions. Flow cytometry revealed that cultured regenerating tissue cells expressed all three mesenchymal stem cell associated markers. The regenerating tissue cells were able to form mineral deposits and lipid-containing adipocytes. However...

‣ SHED: Stem cells from human exfoliated deciduous teeth

Miura, M.; Gronthos, S.; Zhao, M.; Lu, B.; Fisher, L.; Robey, P.; Shi, S.
Fonte: Natl Acad Sciences Publicador: Natl Acad Sciences
Tipo: Artigo de Revista Científica
Publicado em //2003 Português
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To isolate high-quality human postnatal stem cells from accessible resources is an important goal for stem-cell research. In this study we found that exfoliated human deciduous tooth contains multipotent stem cells [stem cells from human exfoliated deciduous teeth (SHED)]. SHED were identified to be a population of highly proliferative, clonogenic cells capable of differentiating into a variety of cell types including neural cells, adipocytes, and odontoblasts. After in vivo transplantation, SHED were found to be able to induce bone formation, generate dentin, and survive in mouse brain along with expression of neural markers. Here we show that a naturally exfoliated human organ contains a population of stem cells that are completely different from previously identified stem cells. SHED are not only derived from a very accessible tissue resource but are also capable of providing enough cells for potential clinical application. Thus, exfoliated teeth may be an unexpected unique resource for stem-cell therapies including autologous stem-cell transplantation and tissue engineering.; Masako Miura, Stan Gronthos, Mingrui Zhao, Bai Lu, Larry W. Fisher, Pamela Gehron Robey and Songtao Shi

‣ Lineage differentiation of mesenchymal stem cells from dental pulp, apical papilla, and periodontal ligament

Akiyama, K.; Chen, C.; Gronthos, S.; Shi, S.
Fonte: Humana Press Publicador: Humana Press
Tipo: Parte de Livro
Publicado em //2012 Português
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Recently, a variety of mesenchymal stem cells (MSCs), including dental pulp stem cells, stem cells from human exfoliated deciduous teeth, stem cells from apical papilla, periodontal ligament stem cells, and mesenchymal stem cells derived from human gingival, were isolated from orofacial and dental tissues. However, it is unknown whether these orofacial stem cells are derived from mesoderm or neural crest cell. In order to encourage orofacial MSC investigation, we provide detailed protocols for assessing lineage ­differentiation of orofacial MSCs.; Kentaro Akiyama, Chider Chen, Stan Gronthos, Songtao Shi

‣ Expression Profile of microRNAs Regulating Proliferation and Differentiation in Mouse Adult Cardiac Stem Cells

Brás-Rosário, Luis; Matsuda, Alex; Pinheiro, Ana Isabel; Gardner, Rui; Lopes, Telma; Amaral, Andreia; Gama-Carvalho, Margarida
Fonte: PLOS Publicador: PLOS
Tipo: Artigo de Revista Científica
Publicado em 17/05/2013 Português
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The identification of cardiac cells with stem cell properties changed the paradigm of the heart as a post mitotic organ. These cells proliferate and differentiate into cardiomyocytes, endothelial and vascular smooth muscle cells, providing for cardiac cell homeostasis and regeneration. microRNAs are master switches controlling proliferation and differentiation, in particular regulating stem cell biology and cardiac development. Modulation of microRNAs -regulated gene expression networks holds the potential to control cell fate and proliferation, with predictable biotechnologic and therapeutic applications. To obtain insights into the regulatory networks active in cardiac stem cells, we characterized the expression profile of 95 microRNAs with reported functions in stem cell and tissue differentiation in mouse cardiac stem cells, and compared it to that of mouse embryonic heart and mesenchymal stem cells. The most highly expressed microRNAs identified in cardiac stem cells are known to target key genes involved in the control of cell proliferation and adhesion, vascular function and cardiomyocyte differentiation. We report a subset of differentially expressed microRNAs that are proposed to act as regulators of differentiation and proliferation of adult cardiac stem cells...

‣ Characterization of human adipose-derived stem cells and expression of chondrogenic genes during induction of cartilage differentiation

Hamid, Adila A; Idrus, Ruszymah Bt Hj; Saim, Aminuddin Bin; Sathappan, Somasumdaram; Chua, Kien-Hui
Fonte: Universidade de São Paulo. Faculdade de Medicina Publicador: Universidade de São Paulo. Faculdade de Medicina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/01/2012 Português
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OBJECTIVES: Understanding the changes in chondrogenic gene expression that are involved in the differentiation of human adipose-derived stem cells to chondrogenic cells is important prior to using this approach for cartilage repair. The aims of the study were to characterize human adipose-derived stem cells and to examine chondrogenic gene expression after one, two, and three weeks of induction. MATERIALS AND METHODS: Human adipose-derived stem cells at passage 4 were evaluated by flow cytometry to examine the expression of surface markers. These adipose-derived stem cells were tested for adipogenic and osteogenic differentiation capacity. Ribonucleic acid was extracted from the cells for quantitative polymerase chain reaction analysis to determine the expression levels of chondrogenic genes after chondrogenic induction. RESULTS: Human adipose-derived stem cells were strongly positive for the mesenchymal markers CD90, CD73, CD44, CD9, and histocompatibility antigen and successfully differentiated into adipogenic and osteogenic lineages. The human adipose-derived stem cells aggregated and formed a dense matrix after chondrogenic induction. The expression of chondrogenic genes (collagen type II, aggrecan core protein, collagen type XI...