Age related changes of the collagen network of the human heart.

The objective of this work was to study the collagen tissue of the human heart muscle as a function of age. The types of collagen, their disposition, as well as the density of collagen tissue and diameter of collagen fibrils were examined. Pieces of the ventricular wall from 12 human hearts, six from young individuals and six from aged individuals were studied by the Picrosirius-polarization method and by transmission electron microscopy (TEM). The results obtained showed the presence of two types of collagen fibers in the ventricular walls - thin, weakly birefringent, greenish fibers (collagen type III) and thick, yellow or red, strongly, birefringent fibers (collagen type I), both in the endomysium and perimysium. In the hearts obtained from old subjects, there were no significant differences in the arrangement of the collagen fibers in relation to the hearts obtained from young subjects. Measurements of collagen content in myocardial tissue suggest that both perimysial and endomysial collagen type I fibers increase in number and thickness in the old. These histochemical results obtained coincided with the electron microscopic observations in showing increase in the number of collagen fibrils with large diameter in the old hearts. These ultrastructural and histochemical characteristics of collagen may provide insights important to assessing the pathogenesis of the cardiac lesions of several cardiopathies in the aged heart.

Identification of collagen, elastic, elaunin and oxytalan fibres in ganglia of the myenteric plexus of the human oesophagus.

The connective tissue associated with the myenteric plexus of the human oesophagus was studied by light and electron microscopy. Collagen fibres were identified by picrosirius staining with polarization microscopy and from their fine structural morphology. A capsule of connective tissue invests the ganglia while septa of connective tissue separate groups of ganglion neurons, surrounding each individual ganglion neuron and each nerve bundle. Collagen fibrils surround the ganglia, each ganglion neuron and each nerve bundle. The fibrils are disposed in various orientations forming networks. Elastic, elaunin and oxytalan fibres were identified by their staining characteristics and fine structural morphology. The bulk of the ganglion sheath consists of coarse elastic fibres and elaunin fibres. Elaunin and oxytalan fibres form the intraganglionic network. Oxytalan, elaunin and elastic fibres appear to be located in areas related to different stresses and deformation to which the ganglia of the myenteric plexus are exposed during the contraction of the esophageal wall. The ganglia of the myenteric plexus of the human oesophagus show structural organisation of the connective tissue component similar to that seen in sympathetic and parasympathetic ganglia.

Functional anatomy of the tela submucosa of the valva ileocecalis in the adult man.

The collagen and elastic fibres of the tela submucosa and their relationships with the tunica muscularis in the human ileocecal valve were studied in 61 anatomic specimens of adult individuals, using meso- and microscopical technics. 2 fibrous components were described: one intrafascicular, which arises from the muscular bundles, and another, interfascicular, which coming from the connective intermuscular layer of the tunica muscularis, pass between the annular bundles toward the tela submucosa. In the tela of the terminal ileum these fibrous components form, like the muscular bundles of the annular layer, a "polar" system, which vanishes at the level of the "marginal sphincter" and in the cecocolic aspect of the ileal papilla. A system of muscular-elastic-collagen bundles is described in these 2 last portions, extending from the tunica muscularis toward the tela submucosa. 2 patterns of arrangements were observed in the tela submucosa: one lamellar, in the terminal ileum and part of the ileal papilla, and another areolar, in the apex and part of the cecocolic aspect of the papilla. A morphometric study was performed in order to estimate the distribution of fat cells in the tela submucosa of the ileocecal valve. It revealed a gradual increase of fat cells amount toward the apex and cecocolic aspect of the papilla ilealis. Some morphofunctional considerations are made, concerning the ileocecocolic junction control.

Surgical and ethnic anatomy of the relationships between the small saphenous vein and the common peroneal and tibial nerves in adult males.

A comparative analysis of the measurements of the distances between the small saphenous vein and the common peroneal and tibial nerves at the back of the knee was performed in melanodermal and leukodermal male adults. The positions in which the vein lies ore closely to the nerves are stressed and should be considered as critical in possible surgical damage to the nerves during saphenectomy.