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C Capdevila

Publications and source records attributed to C Capdevila.

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Effect of spontaneous pathology and thrombin on leukocyte adhesion to rat aortic endothelium.

Leukocyte adhesion and other injury parameters have been studied in the aortic endothelium of Sprague-Dawley rats in two situations: (1) spontaneous pathology in conventional rats with antibodies to Mycoplasma pulmonis and/or Kilham or Sendai viruses, and (2) intravascular coagulation by thrombin administration in SPF rats. Adhesion (esterase (+) leukocytes/mm2) in SPF rats was 8 +/- 5 (n = 12). Adhesion in 38% of the conventional rats was 54 +/- 27 (n = 8), half of them being non-analyzed and the rest having antibodies to M. pulmonis and/or Kilham rat virus. In 19 rats with antibodies to M. pulmonis and/or Kilham or Sendai viruses, AgNO3 and hematoxylin staining of the aortic endothelium showed an increase in leukocyte adhesion, and the presence of argyrophilic cells, stigmata and granularity--severe endothelial lesions being observed in some cases. Adhesion in rats after 0.25, 1, 3 and 6 h of thrombin administration (30 units/100 g) was not different from controls. Adhesion after 24 h was 108 +/- 53 (n = 10) and 60 +/- 59 (n = 10), and 22 +/- 20 (n = 10) in rats treated with thrombin plus heparin or hirudin, respectively. Thrombin produced endothelial lesions at all times studied, and these included membrane blebs, platelet and erythrocyte adhesion and alterations in the pattern of endothelial esterase activity.

Animals

Technical considerations in evaluating the endothelial integrity of rat aortic preparations with silver staining.

Assessment of endothelial integrity is an obligatory step in many pharmacological studies. Integrity of endothelium is affected by manipulations performed during the removal and cleaning of the vessel and by some of the silver-staining techniques utilized for demonstrating interendothelial junctions. When aortas were cleaned of periadventitial tissue in cold Tris-saline (once separated from the animal) by untrained personnel, only 45% of the endothelium was preserved. When cleaning was performed in situ by trained personnel while flushing with cold Krebs-Ringer-6% albumin, over 95% was left intact. AgNO3-staining performed before fixation produced a 50% loss of endothelium when using NH4Br and (NH4)2S as developers. AgNO3-staining performed after fixation produced over 95% recuperation of endothelium when 2% glutaraldehyde, 150 mM NaCl, 40 mM phosphate buffer, pH 7.4, were utilized as initial fixative, NH4Br and (NH4)2S being equally effective as developers. Chloride ions were necessary to intensify silver lines. Several patterns of deendothelization were produced by mechanical and chemical injury with saponin, NH4Br and (NH4)2S. In all cases, hematoxylin staining was employed as an auxiliary technique to interpret images of injured endothelium. Presence of albumin protected the endothelium from mechanical damage.

Animals

Adhesion of leukocytes to the aortic endothelium of conventional, specific pathogen free (SPF) and hypercholesterolemic SPF rats.

Adhesion of leukocytes to the aortic endothelium was studied in specific pathogen-free (SPF) and conventional rats and in SPF rats with diet-induced hypercholesterolemia. Nonspecific esterase activity with alpha-naphthyl acetate as substrate was used to characterize the adhered cells. Phagocytic activity was determined by injecting i.v. 0.1-0.4 ml/100 g doses of Monastral blue B (MbB). Adhesion in SPF rats was 8 +/- 4 esterase (+) cells/mm2. Adhesion in conventional rats was of the same order except in 2 cases with antibodies to Mycoplasma pulmonis and Kilham rat virus, where adhesion was 44 and 68 esterase (+) cells/mm2, respectively. For all MbB doses studied, phagocytic activity arose in a percentage of the adherent cells, ranging from 5 to 85%. Rats fed the hyperlipidic diet for 15 days developed severe hypercholesterolemia and adhesion was drastically increased to 200-700 esterase (+) cells/mm2. Results indicate that: (1) spontaneous pathology in rats may produce an increased adhesion of leukocytes to the endothelium, and (2) phagocytic activity is only expressed in a fraction of the esterase (+) cells adhered to the endothelium.

Animals

Technical considerations in evaluating the adhesion of leukocytes to aortic endothelium of the rat.

Comments on techniques for characterizing leukocytes adhered to the aortic endothelium of the rat are given. Alpha-naphthyl acetate esterase positive leukocytes were studied by optical microscopy of en face intima-media preparations. Results indicate 1) 1% paraformaldehyde-2% glutaraldehyde is a better fixative than formalin-calcium or 4% paraformaldehyde with or without 1.5 mM CaCl2; the latter produces distortion of leukocytes, endothelial desquamation and enzymate inhibition, 2) washing the aorta with phosphate-buffered saline for 90 sec prior to fixation-perfusion produces a notable decrease in the number of leukocytes adhered, 3) diazotized parasaniline is better than fast blue RR salt as coupling agent in the esterase reaction, and 4) counterstaining with 1% methyl green for 1 min, before or after the esterase reaction, is not adequate because of limited contrast and the heavy staining of smooth muscle. Counterstaining with Gill's hematoxylin No. 3 for 90 sec is adequate only when done before the esterase reaction. Inhibition of endothelial esterase activity by hematoxylin decreases background, favors contrast of adhered leukocytes and makes it possible to observe nucleus-cytoplasm relations.

Animals

Codependency: a critique.

An examination of the origins and development of the codependency concept finds it rooted in an obsolete disturbed-personality hypothesis. Both the current literature and treatment philosophy in the chemical dependency field reflect this perspective and continue to perpetuate a pathogenic view of wives who have chemically dependent husbands. Methods of treatment and the validity of treatment for what remains an unverified diagnostic entity are challenged on the grounds of professional ethics and therapeutic efficacy.

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