PubMed Health⌕ Search

Biomedical subjects

A Alvarez-Morujo

Publications and source records attributed to A Alvarez-Morujo.

15 recordsLinked to original sources
PubMed1992

[Morphologic substrates of the ventricular route of secretion and transport of substances in the tubero-infundibular region of the hypothalamus. Ultrastructural study].

Ultrastructural studies of the ependyma of the tuberoinfundibular region of the rat hypothalamus have revealed the existence of intraventricular axonal endings and of cytoplasmic blebs and bulbs that project from the apical surface of the ependymal cells to the ventricular lumen. All these structures account for the processes of ependymal apocrine secretion and the neuroventriculocrinia, and hence the release of biologically active substances into the cerebrospinal fluid (CSF). These substances contained in the CSF must act on the nervous nuclei of the tuberoinfundibular region, such as the arcuate nucleus, which is very important in the neuroendocrine regulation of the anterior pituitary gland. Dilated intercellular spaces among neighbouring ependymocytes of this region, small intraependymal cisternae and, in particular, a lateral prolongation of the infundibular recess, which courses through the nervous tissue between the arcuate nucleus and the median eminence from the vertex of the lateral angle of the infundibular recess, may be the route followed by the CSF from the third ventricle to the tissue compartment of the tuberoinfundibular region. Also studied are the cisternae of the region and the relationships of these with the lateral prolongation of the infundibular recess. Some of these cisternae may be filled by the CSF through the prolongation. In this way, the tissue compartment of CSF would be enlarged, and hence the ventricular route for the secretion and transport of biologically active substances would be potentiated.

Animals↗
PubMed1978

The collagen of the gingiva and of its blood vessels.

The collagen of the gingiva and that of its blood vessels of several animal species and of man were studied with the scanning electron microscope following corrosion with pancreatin at 0.3%. The gingival collagen forms fundamental cells or fasciculi that are distributed throughout the entire territory. In the interior of the cells there are small balls either detached or in clusters. Because of the contact and the fusion of these balls with the collagenic fasciculi, and due to their resistance to the pancreatin corrosion procedure, we believe them to be condensations of collagen. The approximate size of these balls was 2 micrometer. The fasciculi that surround these cells have either the form of bundles or are united in bands. There is an abundance of blood vessels in the gingiva and they are surrounded by collagen. This collagen can assume any of varied positions. The relations that exist between the vascular collagen and that of the gingiva are different in every case.

Animals↗
PubMed1978

New capillary collagen of cutaneous scars.

The capillary collagen of several human keloids was studied. In the majority of the preparations, the collagen had the appearance of an amorphous mass where the amorphous material of the intercellular component was mixed with the newly formed collagen. The vessels of these regions offered neither definite form nor structure but rather a mixture of well-formed fibers and of other fibers still in the process of formation. The principal characteristic of the newly formed vascular collagen was its distribution in the form of rings, each of which was united in turn to other rings. Fibers could be seen radiating from the periphery of these rings and served to join the rings to the surrounding intercellular amorphous substance. The vessels presented different disposition and structures depending upon their grade of development, which is never complete.

Capillaries↗
PubMed1975

Morphological aspect of the skin terminal corpuscles, previous corrosion with pancreatin.

The capsulated corpuscles of the skin have been studied by pancreatin corrosion methods. With this corrosion, Meissner's corpuscles disappear while those, whose fundamental structure is collagenous, remain intact. We have observed structural differences in these collagenous corpuscles, some being formed as a fine reticulum or with longitudinal or concentric sheaths. Within the corpuscle, there is a totally vascular compartment, the 'vascular hill', which is easily differentiated from the other laminar or reticular segment which is the 'nerve hill'. We conclude that the connective tissue arrangement and the vascular content of the corpuscles contribute to the regulation of the different degrees of sensations perceived by these corpuscles. The tendency that these corpuscles show to unite may be caused because the places, where they are grouped, are the points of greatest sensory perception.

Collagen↗
PubMedDate not supplied

[Various aspects of the vessels of the renal glomerulus seen through the scanning electron microscope].

The kidney glomeruli of the rabbit have been examined by means of repletion with celloidin and subsequent corrosion. The observation has been done with a scanning electronic microscope. In their most general and common aspect, the glomeruli have variations in their arteries; in some cases these are homogenous whilst in others they may be different within a single glomerulus and different among each other. When the glomeruli are dissected, these differences are seen much better as there can be seen to be several collaterals, those emerging from the afferrent trunk which may have different devices and several shapes as some are more or less elongated whilst in other circumstances these arteries are spiral with numerous curls. We cannot specify whether these differences are purely morphological or different functional states. When glomeruli are observed in a single area, they present different shapes and sizes which suggests that these differences are typical of each glomerulus and never dependent upon the topography where they are located. The arteries of the glomeruli are generally arranged in lobules. These may be different in the size, length and arrangement of the vessels since, as we clearly state in this paper, the vascular lobules are different from each other within a single glomerulus.

Animals↗
PubMedDate not supplied

[Various aspects of renal pyramid collagen seen by scanning electron microscopy].

In apparently normal kidneys, viewed with a scanning electromicroscope, it has been observed that the renal pyramid has a collagen arranged in cells which cover vessels and tubules. These cells vary in arrangement and structure. In spite of the apparent normality, collagen variations are observed. Sometimes as a result of the increased intensity and other times because forms of neocollagen appear with accumulations of essential substances. This fact suggests that the said changes involve two circumstances. Either this tissue changes continuously or the said kidneys have some lesion in their collagen which leads to new forms of neocollagen appearing and to the great richness of essential substances.

Animals↗