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Immunocytochemical staining of the glial fibrillary acidic protein (GFAP) was utilized to characterize the processes of the astrocytes enveloping the vessel wall in the central nervous system. The study was carried out in the mesencephalic lobes of 18 and 20 incubation-day chick embryos and of 20 day chickens. A perivascular GFAP positivity was mainly detectable in the vessel portions running within the tectum white layers, while it was scarce, or absent, in the grey ones. The perivascular GFAP negativity in the tectum cellular layers was not considered result of the absence of astrocytic endfeet since our previous electronmicroscopical studies evidenced an almost complete perivascular astrocytic ring throughout the tectum layers at hatching time. Present data rather suggest that the expression of the GFAP-made intermediate filaments in developing astrocytes might be controlled by the surrounding microenvironment.

Using labelled ligand-binding methods, previous studies have identified specific angiotensin II receptors (Ang II-Rs) in eel liver, kidney and intestine membranes. Isoelectric focusing on polyacrylamide gels also showed that there are two Ang II-R isoforms in eel liver, focusing at isoelectric points (pI) 6·5 and 6·7. These may have different functions. In contrast, eel enterocyte plasma membrane and renal brush border membranes contain only the pI 6·5 form. To characterize the eel receptors more fully, a newly developed monoclonal antibody (6313/G2) which selectively recognizes the AT1 subtype of mammalian Ang II-R was used. In ligand-binding experiments, the preincubation of eel liver membranes with 6313/G2 antibody eliminated the specific [3,5-3H]Tyr4-Ile5-Ang II binding. Moreover, Ang II—receptor complexes from solubilized liver membranes, which were immunoprecipitated by 6313/G2-coated beads, had a pI of 6·5. In immunoblotting experiments, the antibody recognized the isoform focusing at pI 6·5 in eel intestine and liver preparations, but not the liver pI 6·7 isoform. Immunoblotting of SDS gels showed that the antibody bound to a single protein of molecular mass of 75 kDa in eel liver, gill and kidney and to a doublet of molecular mass of about 74 and 75 kDa in intestinal membrane preparations. Immunocytochemistry of paraffin-embedded and cryostat sections of eel liver, kidney, intestine and gill showed that antibody 6313/G2 bound to uniformly distributed intracellular sites and cell surface membranes in proximal tubular cells, absorptive intestinal cells, hepatocytes and chloride cells. It also stained endothelium and both the longitudinal and circular layers of smooth muscle cells in the intestine. The data suggest that the previously described Ang II-R from eel liver, kidney and intestine may be similar to the mammalian AT1 subtype.

Twelve ataxic subjects (seven with Friedreich's heredo-ataxia and five with a cerebellar vascular or traumatic lesion) were examined by way of urodynamic evaluation. The results explain the role the cerebellum plays in the modulation of the micturition reflex and confirm the importance of bilateral encephalic damage in causing vesico-sphincteral malfunctioning and the important role of the lateral myelon cords in transporting bladder proprioceptive sensitivity.

In this research we studied the interrelationships between the progression of morphological damage and leucocyte populations in the last ileal loop after blockage of blood supply subsequent to arterial and venous occlusion. Our morphological data on the staging of the ileal wall damage agree with those reported in literature. In addition we described that in the ischemic loop the number of lymphocytes appear decreased and polymorphonuclear cells degranulate actively.

Abstract —Because oleic acid is implicated in the antiatherogenic effects attributed to the Mediterranean diet, we investigated whether this fatty acid can modulate endothelial activation, ie, the concerted expression of gene products involved in leukocyte recruitment and early atherogenesis. We incubated sodium oleate with human umbilical vein endothelial cells for 0 to 72 hours, followed by coincubation of oleate with human recombinant tumor necrosis factor, interleukin (IL)-1α, IL-1β, IL-4, Escherichia coli lipopolysaccharide (LPS), or phorbol 12-myristate 13-acetate for a further 6 to 24 hours. The endothelial expression of vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and intercellular adhesion molecule-1 was monitored by cell surface enzyme immunoassays or flow cytometry, and steady-state levels of VCAM-1 mRNA were assessed by Northern blot analysis. At 10 to 100 μmol/L for >24 hours, oleate inhibited the expression of all adhesion molecules tested. After a 72-hour incubation with oleate and a further 16-hour incubation with oleate plus 1 μg/mL LPS, VCAM-1 expression was reduced by >40% compared with control. Adhesion of monocytoid U937 cells to LPS-treated endothelial cells was reduced concomitantly. Oleate also produced a quantitatively similar reduction of VCAM-1 mRNA levels on Northern blot analysis and inhibited nuclear factor-κB activation on electrophoretic mobility shift assays. Incubation of endothelial cells with oleate for 72 hours decreased the relative proportions of saturated (palmitic and stearic) acids in total cell lipids and increased the proportions of oleate in total cell lipids without significantly changing the relative proportions of polyunsaturated fatty acids. Although less potent than polyunsaturated fatty acids in inhibiting endothelial activation, oleic acid may contribute to the prevention of atherogenesis through selective displacement of saturated fatty acids in cell membrane phospholipids and a consequent modulation of gene expression for molecules involved in monocyte recruitment.

The wall of the eye bulbs of 15 chick embryos, immediately after their transfer to Hanks fluid, was irradiated with a CO2 laser, focused on the 12th conjunctival papilla or on its prospective area. This 'in vitro' irradiation was performed under the following main parameters: (a) beam power congruent to 4W; (b) exposure time = 1/30 sec; (c) thickness of the fluid (Hanks solution) on the target surfaces = 0, 3 divided by 0, 7 mm. The same area of the eye bulb surface of other 15 chick embryos was irradiated 'in ovo' under the following conditions: (a) congruent to 4W; (b) = 1/10 sec; (c) (amniotic fluid + albumen) = 1 divided by 1, 5 mm. In the L/M analysis so far carried out, the lesions produced 'in vitro' and 'in ovo' showed a number of qualitative resemblances: i.e., disappearance of epithelial cells and numerous pyknoses in the cells left 'in situ'; decrease in thickness of the outer layer of the scleral mesenchyme, whose cells appeared closer to each other-owing to reduction of the intercellular spaces-, and often pyknotic. It is possible that the same mechanisms underlie such morphological aspects, observed in both groups of irradiated eyes. On the other hand, some quantitative differences were observed between the 'in vitro' and 'in ovo' lesions, the extent in surface and depth of the latter being appreciably lesser. Presumably the genesis of such differences could have been influenced by the physico-chemical differences between the fluids covering the target surfaces: Hanks fluid and, respectively, amniotic fluid + albumen.(ABSTRACT TRUNCATED AT 250 WORDS)