Distribution of collagen fibers in the aggregated lymphoid follicles of swine terminal ileum.

The arrangement of the collagen bundles was studied in the Peyer's patches of swine terminal ileum, by means of light microscopy (using silver-impregnation technique and picrosirius F3BA staining) and scanning electron microscopy (after NaOH-maceration). The lymphoid tissue forms a large and continuous patch along the antimesenteric border. The follicles are disposed mainly in the tela submucosa and sometimes they reached in the tunica mucosa surface (follicle/dome structures). Some follicles are located in the lamina propria of the tunica mucosa. Light microscopy showed black and brown-stained fibers, and yellow and red, and green-stained fibers, respectively by silver impregnation technique and picrosirius red staining, in the tela submucosa. In this tela, by scanning electron microscopy, the collagen fibers appeared as thick bundles forming a network of parallel layers. This network was denser in the interfollicular than in the follicular area, and formed a capsule surrounding the lymphoid follicles. Our results pointed out that a clear correspondence exists between the findings of currently used light microscopy techniques and the scanning electron microscopy after alkali-water maceration method. The arrangement of the collagen fibers in the antimesenteric border of the tela submucosa suggested a functional compartmentalization within the aggregated lymphoid follicles. This could facilitate the antigen-to-cell and cell-to-cell interaction during the immune response and thus create a suitable microenvironment for an active cell metabolism. The tunica mucosa showed a porous structure and its frequent gaps were likely the sites through which lymphocytes and other cells could freely migrate thus participating in the immunological activities of these structures.

The frenula of the papilla ilealis of the swine.

The junction between the small and the large intestines has been studied in several animals since this region makes an important intestinal transition. Like humans the swine have a structure that forms a boundary between the cecum and the ascending colon - the frenulum papillae ilealis dorsalis and ventralis. Nevertheless the morphology and physiology of this is poorly known. The aim of this work is to describe the morphology of the swine's frenula and to trace some elements of comparative anatomy. The macroscopic research was done on 33 animals and the results were analyzed by Wilcoxon test. The arrangement of the tunica muscularis was studied in 12 animals by dissection, after immersion in 50% nitric acid solution, and the light microscopic studies were performed in 15 animals. In all of the cases it was observed that it was the frenulum papillae ilealis, dorsal and ventral, which formed the internal boundary between the cecum and the ascending colon. They were constituted of the tunica mucosa, tela submucosa and tunica muscularis of the large intestine. The swine's frenula papillae ilealis participate in the functioning of the ileocecocolic "pylorus". The macro- and microscopic morphology of the swine's frenula are similar to that of the man, indicating that this animal would be a good model for the experimental studies.

Atlas com ponticulus posticus bilateral / Atlas with bilateral ponticulus posticus: a case report

Introdução: A margem inferior da membrana atlantoccipital posterior pode ocasionalmente estar ossificada em virtude do aparecimento de um centro de ossificação incomum. Quando isso acontece, pode haver formação de uma pequena ponte óssea (ponticulus posticus) sobre o sulco para a artéria vertebral. É relatado o caso de um atlas com ponticulus posticus bilateral, em que o direito não se fixa na massa lateral, mas sobre uma ponte óssea, que une o processo transverso àquela massa. Objetico: Analisar um caso de pnticulus posticus em uma vértebra atlas humana. Material e métodos: O presente estudo enfoca, de modo descritivo, um atlas obtido por dissecação da coluna vertebral de um indivíduo adulto do sexo masculino. Resultados: O atlas apresentava um ponticulus posticus sobre o sulco para a artéria vertebral bilateralmente. Conclusão: É relatado um caso de ponticulus posticus em uma atlas humano, considerando-se suas variações e importância clínica (isquemia vertebrobasilar e enxaqueca sem aura)

The anatomosurgical arterial segments of the kidney of mongrel caprines

Thirty pair of kidneys of adult, mongrel caprines, Capra hircus, were studied after injection of a plasticsubstance followed by corrosion, focusing on the main branches of the terminal divison of the renal artery and their distribution through renal sectors. Segmental arteries and consequently anatomicosurgical segments were identified. The right and left renal aa, were always single and bifurcated into ventral and dorsal sectorial arteries, which in turn originate, off the segmental arteries. Extra-hilar arteries were foundin the right kidney 20 (per cent) and left 10 (per cent) and were also considered segmental arteries. More frequently there were 4 anatomosurgical segments in the ventral sector being 53 (per cent) on the right and 66.7 (per cent) on the left, and in left kidney, eight anatomosurgical segments: ventrocranial, ventromediocranial, and ventrocaudal, in the ventral sector, and dorsocranial, dorsomediocranial, dorsomediocaudal and dorsocaudal, in the dorsal sector. Bilateral symmetry of the renal arterial anatomosurgical segmentation occured in 20 (per cent).