Leishmaniosis--a report about the microvascular and cellular architecture of the infected spleen in Canis familiaris.

Leishmaniosis is an anthropozoonosis caused by an intracellular protozoan parasite that causes a wide spectrum of diseases in humans and dogs worldwide. In the Mediterranean basin, Portugal, Central and South America, and in the Middle East, visceral leishmaniosis is caused by Leishmania infantum. In these areas, dogs are believed to be the natural reservoirs of this parasite. In the case of visceral leishmaniosis, the spleen is one of the several hematopoietic and immunocompetent organs involved. Since this viscera is a blood filter, the authors investigated the expression of the morphological and microvascular environment and modifications of the spleen cell population related to immunological responses to this parasitic condition. The tools used to perform this study were scanning electronic microscopy of intact tissue and corrosion casts, transmission electronic microscopy, histology and immunohistochemistry. The results reveal three important modifications concerning the spleen's microvascular architecture when compared with its normal pattern, independently of the serological titer obtained with indirect immunofluorescence. (1) A marked scarcity of the sinusoidal system sheet that surrounds the central artery/arteriole of the white pulp; (2) A huge development of pulp venules and veins; (3) The presence of a surprising development of reticular fibers. The authors postulate that independent of the virulence of the parasite involved and the type of immunity prevalent in a particular host, the spleen develops blood dynamic conditions that permit reduction in the speed of blood flow so that cells involved in immunological processes can proliferate and differentiate, and also contributes to trapping lymphocytes within the area through the differentiation of characteristics that resemble those of HEV endothelial cells.

[The myth of Apollo and Marsyas. Artistic representations and anatomical studies]. / A lenda de Apolo e Mársias. Representações artísticas e estudos de anatomia de superfície.

The authors analyze an interesting sculpture found in the gardens of a 17th Century palace in Lisbon, representing the myth of Apollo and Marsyas, which led them to compare the details of the sculpture of the flayed satyr with the previous anatomic studies by Leonardo da Vinci (cc.1510-1530) or Vesalius (cc.1543). The photographic material obtained from the 17th century Italian sculpture presents amazing similitude with these, earlier, 16th century anatomical studies. As a complement to this study, the authors compare the sculptures with the artistic evidences, found throughout the world, of the 17th century interest for the representation of the myth of Apollo and Marsyas, which could be considered as a meaningful artistic movement of the Renaissance and neo-classic art. Some of the artistic representations of surface anatomy depict other motives, as is the case of the self-portrait of Michelangelo, painted in the Sistine Chapel, in honour of St. Bartholomew.