Pesquisa com Células-tronco: Mitos e Realidade

RESUMENDurante os últimos anos, diversos tipos de células-tronco (CT) têm sido descobertas a partir das células embrionárias e de adultos. Cada uma delas surge como promessa revolucionária no futuro da regeneração celular para tratar uma grande variedade de doenças. A pesquisa com estas células vem recebendo um grande apoio das políticas científicas na maioria dos países, provocando um intenso debate ético e religioso e despertando um grande interesse do público em geral. Entretanto, muito ainda há para ser investigado, através de pesquisas básicas e pré-clinicas, antes (irar o de) que possamos acreditar que este tipo de terapia esteja totalmente pronto para ser empregado nas pesquisas clínicas. O desenvolvimento de linhagens de CT in vitro, para o entendimento dos fatores envolvidos no crescimento e diferenciação celular, bem como o desenvolvimento de protocolos pré-clínicos, mostrando como e por que estas células regeneram os tecidos in vivo, são pontos fundamentais a serem levados em consideração. ABSTRACTDuring the past few years, several types of stem cells have been described, both embryonic and adult ones. Each one of them represents a revolutionary promise in the cellular regeneration field, for future treatment of many diseases. Research using stem cells is being greatly supported in most countries, provoking an intense ethical and religious debate among scientists as well as the general public. There is, however, a long road to go in basic research before we can safely and effectively use this technology for treating diseases. The in vitro development of stem cell lineages and pre-clinical protocols will allow us to understand more about how these cells grow and differentiate, as well as how and why these cells regenerate tissues. Key words: Stem cells, Cell theraph

Pesquisa com Células-tronco: Mitos e Realidade

RESUMENDurante os últimos anos, diversos tipos de células-tronco (CT) têm sido descobertas a partir das células embrionárias e de adultos. Cada uma delas surge como promessa revolucionária no futuro da regeneração celular para tratar uma grande variedade de doenças. A pesquisa com estas células vem recebendo um grande apoio das políticas científicas na maioria dos países, provocando um intenso debate ético e religioso e despertando um grande interesse do público em geral. Entretanto, muito ainda há para ser investigado, através de pesquisas básicas e pré-clinicas, antes (irar o de) que possamos acreditar que este tipo de terapia esteja totalmente pronto para ser empregado nas pesquisas clínicas. O desenvolvimento de linhagens de CT in vitro, para o entendimento dos fatores envolvidos no crescimento e diferenciação celular, bem como o desenvolvimento de protocolos pré-clínicos, mostrando como e por que estas células regeneram os tecidos in vivo, são pontos fundamentais a serem levados em consideração. ABSTRACTDuring the past few years, several types of stem cells have been described, both embryonic and adult ones. Each one of them represents a revolutionary promise in the cellular regeneration field, for future treatment of many diseases. Research using stem cells is being greatly supported in most countries, provoking an intense ethical and religious debate among scientists as well as the general public. There is, however, a long road to go in basic research before we can safely and effectively use this technology for treating diseases. The in vitro development of stem cell lineages and pre-clinical protocols will allow us to understand more about how these cells grow and differentiate, as well as how and why these cells regenerate tissues. Key words: Stem cells, Cell theraph

Association between the 1858T allele of the protein tyrosine phosphatase nonreceptor type 22 and type 1 diabetes in a Brazilian population.

The 1858T allele of the protein tyrosine phosphatase nonreceptor 22 (PTPN22) gene has been associated to diabetes in different populations. We investigated a possible relationship between this polymorphism and type 1 diabetes in a cohort of Brazilian patients. A significantly higher frequency of the 1858T allele was observed in diabetic patients (n = 211) than in control individuals (n = 241). Additionally, the heterozygote genotype was also increased in the diabetic group. No association was observed between the PTPN22 T allele and gender, or between T carriers and age of onset of T1D. This work describes for the first time a strong association of the 1858T allele with type 1 diabetes in a Brazilian population, reinforcing the role of this variant as an important susceptibility factor for this disease.info:eu-repo/semantics/publishe

Bio-electrospraying of human mesenchymal stem cells: An alternative for tissue engineering

Bio-electrospraying (BES) is a technique used for the processing of cells and can be applied to tissue engineering. The association of BES with scaffold production techniques has been shown to be an interesting strategy for the production of biomaterials with cells homogeneously distributed in the entire structure. Various studies have evaluated the effects of BES on different cell types. However, until the present moment, no studies have evaluated the impact of BES time on mesenchymal stem cells (MSC). Therefore, the aim of this work was to standardise the different parameters of BES (voltage, flow rate, and distance of the needle from the collecting plate) in relation to cell viability and then to evaluate the impact of BES time in relation to viability, proliferation, DNA damage, maintenance of plasticity and the immunophenotypic profile of MSC. Using 15 kV voltage, 0.46 ml/h flow rate and 4 cm distance, it was possible to form a stable and continuous jet of BES without causing a significant reduction in cell viability. Time periods between 15 and 60 min of BES did not cause alterations of viability, proliferation, plasticity, and immunophenotypic profile of the MSC. Time periods above 30 min of BES resulted in DNA damage; however, the DNA was able to repair itself within five hours. These results indicate that bio-electrospraying is an adequate technique for processing MSC which can be safely applied to tissue engineering and regenerative medicine