The effect of bone marrow-derived stem cells associated with platelet-rich plasma on the osseointegration of immediately placed implants

Stem cells associated with growth factors have been shown to improve bone healing and the osseointegration of dental implants. A Brazilian miniature pig model was used to evaluate the effect of autologous bone marrow-derived mesenchymal stem cells (BM-MS

Morphology and morphometry of feline bone marrow-derived mesenchymal stem cells in culture

Mesenchymal stem cells (MSC) are increasingly being proposed as a therapeutic option for treatment of a variety of different diseases in human and veterinary medicine. Stem cells have been isolated from feline bone marrow, however, very few data exist about the morphology of these cells and no data were found about the morphometry of feline bone marrow-derived MSCs (BM-MSCs). The objectives of this study were the isolation, growth evaluation, differentiation potential and characterization of feline BM-MSCs by their morphological and morphometric characteristics. in vitro differentiation assays were conducted to confirm the multipotency of feline MSC, as assessed by their ability to differentiate into three cell lineages (osteoblasts, chondrocytes, and adipocytes). To evaluate morphological and morphometric characteristics the cells are maintained in culture. Cells were observed with light microscope, with association of dyes, and they were measured at 24, 48, 72 and 120h of culture (P1 and P3). The non-parametric ANOVA test for independent samples was performed and the means were compared by Tukey's test. On average, the number of mononuclear cells obtained was 12.29 (±6.05x10(6)) cells/mL of bone marrow. Morphologically, BM-MSCs were long and fusiforms, and squamous with abundant cytoplasm. In the morphometric study of the cells, it was observed a significant increase in average length of cells during the first passage. The cell lengths were 106.97±38.16µm and 177.91±71.61µm, respectively, at first and third passages (24 h). The cell widths were 30.79±16.75 µm and 40.18±20.46µm, respectively, at first and third passages (24 h).The nucleus length of the feline BM-MSCs at P1 increased from 16.28µm (24h) to 21.29µm (120h). However, at P3, the nucleus length was 26.35µm (24h) and 25.22µm (120h). This information could be important for future application and use of feline BM-MSCs

Avaliação sensitiva, motora e cistométrica de cães com lesão medular crônica, submetidos ao transplante de células-tronco mesenquimais derivadas de tecido adiposo

RESUMO: A utilização de células-tronco na reparação de lesões tem sido extensivamente investigada. Neste estudo, examinamos os efeitos terapêuticos de dois transplantes (12x106 céls/transplante) de células-tronco mesenquimais alogênicas derivadas do tecido adiposo (CTDAs) em 11 cães com lesões crônicas traumáticas toracolombares da medula espinhal. As CTDAs foram foram cultivadas in vitro, a proliferação e a viabilidade foram avaliadas. As suspensões foram expandidas e administradas no espaço intradural com intervalo de uma semana entre transplantes. Os cães foram submetidos à avaliações clínicas, laboratoriais, radiográficas, tomográficas, sensitivas, motoras e cistométricas. A maioria dos animais não tinha raça definida (63,63%), mesma proporção para o acometimento de fêmeas e foi observada predominância de fratura com subluxação vertebral (81,81%). Na comparação dos cães pré e pós-transplante não foram observadas alterações hematológicas e três animais (27,27%) apresentaram cistite bacteriana. Em relação a sensibilidade, motricidade e cistometria, também não houve alterações significativas dos índices antes e pós transplantes, sendo observado a ausência nociceptiva na maioria dos animais (72,73%), paraplegia e incontinência urinária na mesma proporção. Neste estudo concluiu-se que o protocolo utilizado de transplante de CTDAs, demonstrou ser um tratamento seguro para cães com lesão medular crônica, com melhora discreta da funcionalidade vesical, porém sem melhora clínica significativa

Downregulation of the protein synthesis machinery is a major regulatory event during early adipogenic differentiation of human adipose-derived stromal cells

Commitment of adult stem cells involves the activation of specific gene networks regulated from transcription to protein synthesis. Here, we used ribosome profiling to identify mRNAs regulated at the translational level, through both differential association to polysomes and modulation of their translational rates. We observed that translational regulation during the differentiation of human adipose-derived stromal cells (hASCs, also known as adipose-derived mesenchymal stem cells), a subset of which are stem cells, to adipocytes was a major regulatory event. hASCs showed a significant reduction of whole protein synthesis after adipogenic induction and a downregulation of the expression and translational efficiency of ribosomal proteins. Additionally, focal adhesion and cytoskeletal proteins were downregulated at the translational level. This negative regulation of the essential biological functions of hASCs resulted in a reduction in cell size and the potential of hASCs to migrate. We analyzed whether the inactivation of key translation initiation factors was involved in this observed major repression of translation. We showed that there was an increase in the hypo phosphorylated forms of 4E-BP1, a negative regulator of translation, during early adipogenesis. Our results showed that extensive translational regulation occurred during the early stage of the adipogenic differentiation of hASCs