Interações entre sistemas de referência alocêntricos e egocêntricos: evidências dos estudos com direção percebida / Interactions between allocentric and egocentric frames of reference: evidences from studies on perceived direction

Sistemas de referência (frames of reference) são definidos como um locus ou conjunto de loci em relação ao qual as localizações espaciais são determinadas. Os sistemas de referência egocêntricos definem as localizações espaciais em relação ao observador, enquanto que nos sistemas de referência alocêntricos, as localizações são determinadas em relação a loci externos ao observador. Analisamsediversas evidências da utilização destes sistemas de referência pelo sistema visual humano, tanto para tarefas de percepção visual quanto para tarefas de navegação. Hipóteses da dissociação dosistema visual em função destes sistemas de referência são evidenciadas por resultados de estudos neuropsicológicos. O conjunto das evidências experimentais indica uma efetiva interação entre codificações em sistemas de referência egocêntricos e alocêntricos, de modo que os sistemas visual e visomotor introduzem transformações nas coordenadas de um sistema em função de outro, adequando a informação às características das diferentes tarefas.

Frame of reference is a locus or a set of loci in relation to which spatial locations are determined. Egocentrical frames of reference define spatial locations in relation to observer; in allocentricalframes of reference, spatial locations are determined in relation to external loci. Several evidences of usefulness of frames of references to human visual system are analysed, to perceptual tasks as well as navigational tasks. Neuropsychological studies provided empirical support to hypothesis ondissociation of visual system as a function of frames of reference. The whole of experimental evidenceindicates an effective interaction between codings in egocentrical and allocentrical frames of reference,thus visual and visuomotor systems introduce transformations on coordinates of a frame on another,adjusting information to different tasks requirements.

Effect of Rumo Shengji San on Skin Defect After Repair with Tissue-engineered Skin / 中药新药与临床药理

Objective To investigate the effect of Rumo Shengji San on promoting tissue regeneration of skin defect after repair with tissue-engineered skin.Methods The dermal scaffolds were reconstructed by collagen sponge in which human skin fibroblasts were transplanted inside and human keratocytes were transplanted on the surface.The tissue-engineered skin was transplanted into the wound surface of defected skin in naked mice.Rumo Shengji San was applied externally once every other day after transplantation for 2 days.The animals were randomly divided into two groups:external application group and control group,4 mice in each group.The differentiation tissue of the tissue-engineered skin was sampled 9 days after transplantation.The epidermis thickness and dermal capillary proliferation in wound of defected skin were observed with HE staining,and double-labeled immunofluorescence method was used to test dermal laminin(Ln) and typeⅠcollagen protein expression.Results Rumo Sheng Jji San promoted the development of epidermis after transplantation for 9 days.The number of capillaries in dermis was increased,and the expression of Ln and typeⅠcollagen protein was promoted in external application group than that in the control group.Conclusion Rumo Shengji San can promote tissue regeneration of skin defect after repair with tissue-engineered skin.