El tratamiento con relaxina estimula la diferenciación de células madre mesenquimales en osteoblastos

Resumen Antecedentes/objetivo: Varios estudios han determinado que la relaxina estimula la diferenciación y regula la actividad de los osteoclastos maduros, pero se sabe poco sobre su efecto en la diferenciación de las células mesenquimales hacia el linaje osteogénico. Por lo tanto, este estudio tuvo como objetivo determinar el efecto de la relaxina sobre la proliferación y diferenciación del linaje osteoblástico de células mesenquimales derivadas de pulpa dental humana (hDPSC). Materiales y métodos: En este estudio in vitro, las hDPSC fueron caracterizadas y tratadas con relaxina a diferentes dosis (10e80 ng/ml) y tiempos (1e21 días). La morfología se evaluó mediante microscopía y la proliferación mediante un ensayo de resazurina. La diferenciación osteoblástica se evaluó mediante tinción con rojo alizarina, marcaje con fosfatasa alcalina (ALP) y cambios en la expresión de los genes de diferenciación osteoblástica RUNX2 y BMP2. Resultados: El tratamiento con relaxina no indujo cambios en la proliferación o viabilidad de las hDPSCs; sin embargo, se observaron células más grandes y una mayor prolongación citoplasmática. El tratamiento con relaxina (20 y 80 ng/ml) aumentó significativamente la formación de nódulos calcificados en los días 14 y 21. Las señales citoquímicas para la expresión de los genes ALP, RUNX2 y BMP2 aumentaron significativamente (P < 0,05) con el tratamiento con relaxina.Abstract Background/purpose: Several studies have determined that relaxin stimulates differentiation and regulates the activity of mature osteoclasts, but little is known about its effect on the differentiation of mesenchymal cells towards the osteogenic lineage. Therefore, this study aimed to determine the effect of relaxin on the proliferation and differentiation of the osteoblastic lineage of mesenchymal cells derived from human dental pulp (hDPSC). Materials and methods: In this in vitro study, hDPSC were characterized and treated with relaxin at different doses (10e80 ng/ml) and times (1e21 days). Morphology was assessed by microscopy, and proliferation was assessed using a resazurin assay. Osteoblastic differentiation was evaluated by Alizarin Red staining, alkaline phosphatase (ALP) labeling, and changes in the expression of the osteoblastic differentiation genes RUNX2 and BMP2. Results: Relaxin treatment did not induce changes in the proliferation or viability of hDPSCs; however, larger cells and increased cytoplasmic prolongation were observed. Relaxin treatment (20 and 80 ng/ml) significantly increased calcified nodule formation on days 14 and 21. The cytochemical signals for ALP, RUNX2, and BMP2 gene expression were significantly (P < 0.05) increased by the relaxin treatment

Desempenho de borregos desmamados da raça Barriga Negra em Roraima.

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31P Magnetic resonance spectroscopy study of phosphocreatine recovery kinetics in skeletal muscle: the issue of intersubject variability

AbstractWe have analyzed by 31P MRS the relationship between kinetic parameters of phosphocreatine (PCr) recovery and end-of-exercise status under conditions of moderate and large acidosis induced by dynamic exercise. Thirteen healthy subjects performed muscular contractions at 0.47 Hz (low frequency, moderate exercise) and 0.85 Hz (high frequency, heavy exercise). The rate constant of PCr resynthesis (kPCr) varied greatly among subjects (variation coefficients: 43 vs. 57% for LF vs. HF exercises) and protocols (kPCr values: 1.3±0.5 min−1 vs. 0.9±0.5 min−1 for LF vs. HF exercises, P<0.03). The large intersubject variability can be captured into a linear relationship between kPCr, the amount of PCr consumed ([PCr2]) and pH reached at the end of exercise (pHend) (kPCr=−3.3+0.7 pHend-0.03 [PCr2]; P=0.0007; r=0.61). This dual relationship illustrates that mitochondrial activity is affected by end-of-exercise metabolic status and allows reliable comparisons between control, diseased and trained muscles. In contrast to kPCr, the initial rate of PCr recovery and the maximum oxidative capacity were always constant whatever the metabolic conditions of end-of-exercise and can then be additionally used in the identification of dysfunctions in the oxidative metabolic pathway

Perfil dos produtores e da produção de leite e derivados nos municípios de São Luiz e Rorainópolis em Roraima.

Em 2017 a empresa lançou um edital buscando propostas que contribuíssem com tecnologias sustentáveis para a Amazônia com foco na agricultura familiar. Dentre as principais linhas temáticas expressas incluiu-se a recuperação de pastagens degradadas visando atender a um dos anseios daqueles que lidam diariamente com atividades pastoris. Dentre as ações propostas neste sentido fazia parte a realização de um diagnóstico sobre a atividade leiteira nos municípios de São Luiz e Rorainópolis. Esta publicação apresenta informações sobre o perfil da produção e dos produtores de leite e derivados naqueles municípios, iniciando-se com uma visão geral sobre a produção de leite no contexto mundial, brasileiro, regional e estadual. Segue-se com dados sobre aspectos socioeconômicos, sobre os estabelecimentos rurais e seus proprietários

Práticas e custos de produção para implantação de bosques de Tecas (Tectona grandis) em pastagens de Roraima.

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Damped Bloch oscillations of cold atoms in optical lattices

The paper studies Bloch oscillations of cold neutral atoms in the optical lattice. The effect of spontaneous emission on the dynamics of the system is analyzed both analytically and numerically. The spontaneous emission is shown to cause (i) the decay of Bloch oscillations with the decrement given by the rate of spontaneous emission and (ii) the diffusive spreading of the atoms with a diffusion coefficient depending on {\em both} the rate of spontaneous emission and the Bloch frequency.Comment: 10 pages, 8 figure

Recuperação de pastagens degradadas em propriedade particular na região da Confiança, Município do Cantá, Roraima.

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Aproximação de modelo determinístico para estimação diária de umidade relativa do ar na região do Apiaú , Roraima

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