Plasticity of fetal cartilaginous cells.

Tissue-specific stem cells found in adult tissues can participate in the repair process following injury. However, adult tissues, such as articular cartilage and intervertebral disc, have low regeneration capacity, whereas fetal tissues, such as articular cartilage, show high regeneration ability. The presence of fetal stem cells in fetal cartilaginous tissues and their involvement in the regeneration of fetal cartilage is unknown. The aim of the study was to assess the chondrogenic differentiation and the plasticity of fetal cartilaginous cells. We compared the TGF-β3-induced chondrogenic differentiation of human fetal cells isolated from spine and cartilage tissues to that of human bone marrow stromal cells (BMSC). Stem cell surface markers and adipogenic and osteogenic plasticity of the two fetal cell types were also assessed. TGF-β3 stimulation of fetal cells cultured in high cell density led to the production of aggrecan, type I and II collagens, and variable levels of type X collagen. Although fetal cells showed the same pattern of surface stem cell markers as BMSCs, both type of fetal cells had lower adipogenic and osteogenic differentiation capacity than BMSCs. Fetal cells from femoral head showed higher adipogenic differentiation than fetal cells from spine. These results show that fetal cells are already differentiated cells and may be a good compromise between stem cells and adult tissue cells for a cell-based therapy

Doenças foliares da pupunheira (Bactris gasipaes) no Estado do Paraná.

Visando fornecer subsidios para futuras acoes de pesquisa, este trabalho tem o objetivo de apresentar informacoes sobre a situacao fitossanitaria da cultura da pupunha no Estado do Parana. Foi constatada a ocorrencia de antracnose, causada por Colletotrichum gloesporioides, em oito plantios e dois viveiros amostrados nos municipios de Morretes, Paranagua, Sao Tome e Paranavai, Estado do Parana. A ocorrencia de antracnose foi mais severa em mudas em formacao em viveiros e tambem nos plantios com ate 6 a 8 meses. Foram constatadas as presencas de Fusarium sp. e Cladosporium sp., causando queima das folhas, em plantas jovens.Notas tecnicas

Transformations of Heun's equation and its integral relations

We find transformations of variables which preserve the form of the equation for the kernels of integral relations among solutions of the Heun equation. These transformations lead to new kernels for the Heun equation, given by single hypergeometric functions (Lambe-Ward-type kernels) and by products of two hypergeometric functions (Erd\'elyi-type). Such kernels, by a limiting process, also afford new kernels for the confluent Heun equation.Comment: This version was published in J. Phys. A: Math. Theor. 44 (2011) 07520