Diversos estudos têm revelado a existência de uma relação entre aspectos psicossociais e o desenvolvimento ou agravamento de dermatoses crônicas, dentre as quais se encontra a psoríase. Fatores psicológicos, stress e outros eventos da vida são capazes de agravar de 40 e 80% dos casos. O estudo objetivou analisar a forma como esses aspectos podem ensejar o surgimento, a reincidência ou a acentuação do quadro clínico. Metodologia: Estudo de casos concretos com pacientes portadores da psoríase, além de uma vasta literatura bibliográfica acerca da temática. Conclusão: Ficou demonstrada a importância do tratamento psíquico e fisiológico, bem como a necessidade do desenvolvimento de estratégias de coping para enfretamento das situações sociais envolvidas.

The low temperature magnetization, specific heat, electrical resistance and magnetoresistance have been studied for the Ru-doped La(1.32)Sr(1.68)Mn(2 - y)Ru(y)O(7) (y = 0.0, 0.04, 0.08 and 0.15) layered manganite system. The undoped compound (y = 0.0) shows a sharp ferromagnetic transition (T(C)) accompanied by a metal-insulator transition (T(MI)) at 118 K. The Ru substitution decreases the T(C) and T(MI) temperatures significantly. The temperature dependence of specific heat measurement confirms the decrease in T(C) by observing the anomaly corresponding to T(C). The decreased effective moments from 3.48 μ(B) for the undoped compound to 1.82 μ(B) for the highly doped compound at 5 K indicates the Ru substitution weakens the ferromagnetic order in the low temperature regime and reduces the number of Mn pairs in the highly doped sample. The field dependence of magnetization measurements exhibits an enhancement of the coercive field with increased Ru concentration and gives evidence for the mixed magnetic phase for the highly doped compound. For the undoped sample, a large negative magnetoresistance of 300% at T(C) and 128% at 4.2 K in a 5 T field were observed. The magnetoresistance ratio decreases gradually with increasing Ru substitution. We find that the doped Ru in the Mn site drives the layered manganite system towards a magnetically mixed state. The effects of Ru doping in the transport and magnetic properties will be explained by the antiferromagnetically coupled Ru and Mn sublattices.

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