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P S Gutierrez

Publications and source records attributed to P S Gutierrez.

At least 19 recordsLinked to original sources
PubMed1998

Distribution of hyaluronan and dermatan/chondroitin sulfate proteoglycans in human aortic dissection.

Aortic dissections (AD) are characterized by the separation of the artery into two sheets, possibly due to fragility of the vessel wall. A mucoid histological pattern, imparted to the tissues mainly by hyaluronan and proteoglycans, can be seen in "cysts" and, in chronic cases, in a band of repair tissue. We studied the localization of hyaluronan, versican, decorin and biglycan in situ in aortas of 21 patients with recent AD, 8 with chronic AD and in 15 control cases. None of these substances was increased in the areas of mucoid "cysts" that possibly contain anomalous material. Similar distributions were seen in normal and dissected aortas: versican and hyaluronan were more prominent in the external half of the medial layer where the dissection usually occurs. Since these molecules play a role in resistance to compression, disorders not detected by our method may be involved in aortic dissection. Hyaluronan was seen adjacent to fibrin at the dissection tear, probably as an early wound repair phenomenon. Biglycan, hyaluronan and mostly versican are seen during advanced repairing. The mucoid deposits may represent various compounds which reflect different disorders in vascular biology.

Acute Disease↗
PubMed1997

An in situ quantitative immunohistochemical study of cytokines and IL-2R+ in chronic human chagasic myocarditis: correlation with the presence of myocardial Trypanosoma cruzi antigens.

Inflammatory cells positive for the cytokines IL-2, IL-4, IL-6, TNF-alpha, and IFN-gamma and for IL-2R, as well as CD8+ and CD4+ T cells and B cells were quantified using an immunoperoxidase technique in 25 fresh myocardial fragments from patients presenting with chronic chagasic cardiomyopathy. The presence of Trypanosoma cruzi antigens (Ags) in the myocardium was also investigated. The cases were grouped into group A (no Ag), group B (scarce extramyocardial fiber Ags), and group C (intramyocardial pseudocysts and extramyocardial fiber Ags). IL-2 was detected in very few cells (0.30 +/- 0.40 positive cells/hpf), suggesting immunological imbalance in chronic chagasic patients. IFN-gamma+ was the cytokine most frequently demonstrated (7.52 +/- 5.87 positive cells/hpf) and there was a good correlation between the number of IFN-gamma+ cells and CD8+ T cells in group A. IL-4+ cells were present in higher numbers in group C (2.78 +/- 1.49 positive cells/hpf). TNF-alpha+ (1.59 +/- 1.68 positive cells/hpf) and IL-6+ (2.76 +/- 2.32 positive cells/hpf) cells were present in moderate numbers. Fewer B cells were present, not related with the intensity of T. cruzi Ags. These results suggest that cytokines, as they occur in other infectious diseases, play a fundamental role in the control of T. cruzi in chronic human chagasic disease. A fatal outcome seems to be associated with the increased production of cytokines derived from the Th2 subpopulation of the CD4+ T cells.

Animals↗
PubMed1997

Association of an increase in CD8+ T cells with the presence of Trypanosoma cruzi antigens in chronic, human, chagasic myocarditis.

The role of Trypanosoma cruzi in the pathogenesis of myocarditis in the chronic phase of Chagas' disease is still controversial, with autoimmune mechanisms frequently being proposed. In the present work, we demonstrate that higher numbers of CD8+ T cells are correlated with the presence of parasite antigens, suggesting an important role for the parasite in the development of myocardial inflammation. Quantification of the mean numbers of CD8+ and CD4+ T cells per 400x microscopic field was performed in myocardial specimens from 33 chronic chagasic patients with heart failures (nine biopsies and 24 necropsies), using an immunoperoxidase technique. The cases were grouped according to a semiquantitative score of the relative amounts of T. cruzi antigens: group 1 = absent (14 cases); group 2 = scarce extracellular or intramacrophagic antigens (12 cases); group 3 = many extracellular or intramacrophagic antigens plus T. cruzi intramyocytic pseudocysts (seven cases). The mean numbers of CD8+ and CD4+ T cells in groups 1,2, and 3 were 6.94 and 3.79, 13.89 and 6.24, and 17.91 and 5.97, respectively. The numbers of CD8+ T cells in groups 2 and 3 were significantly higher compared with group 1 (no T. cruzi antigens), but were not different from each other. Scarce, extramyocytic T. cruzi antigens were associated with an intense inflammatory infiltrate, suggesting that delayed-type hypersensitivity immune mechanism is induced by the parasite; intact myocardiocytes containing parasites did not show an inflammatory reaction around them. A poor inflammatory response was frequently associated with many extramyocytic antigens and myocardial parasite pseudocysts, suggesting that active proliferation and dissemination of the parasites occur when the immunologic response is diminished. The number of CD4+ T cells did not vary significantly among the three groups. We conclude that the CD8+ T cell is the main cell type responsible for immune activation in chronic, human, chagasic myocarditis and is probably activated by the presence of T. cruzi antigens associated with internal myocytic host antigens. The absence of a significant member of CD4+ T cells in the presence of T. cruzi antigens suggests inhibition of CD4+ T cell activation or the lack of a class II major histocompatibility complex molecule presentation mechanism.

Antigens, Protozoan↗
PubMed1993

Immunohistochemical characterization of infiltrating cells in human chronic chagasic myocarditis: comparison with myocardial rejection process.

Cellular subpopulations that infiltrate the heart in human chronic chagasic myocarditis were defined immunohistochemically in endomyocardial biopsy (EMB) specimens. T cells formed 96.3% of the inflammatory infiltrate, predominantly CD8+ (cytotoxic/suppressor) T cells. The mean numbers of CD8+ and CD4+ (helper) T cells in the myocarditis were compared to those present in the myocardial rejection process. Mean numbers of CD8+ T cells were similar in both groups of EMB specimens while CD4+ T cell counts, CD4+/CD8+ ratios and CD4+ antigen expression were significantly lower in the chagasic group compared to the myocardial rejection group (P < 0.002). The persistent lower number and diminished expression of CD4+ T cells suggest an immunological imbalance in patients with chronic chagasic myocarditis. A possible participation of Trypanosoma cruzi parasites in the development of such immunological abnormalities is also discussed.

Adult↗
PubMed1993

[Analysis of the composition and spatial disposition of atherosclerotic plaques localized in epicardial coronary artery bifurcations in adults].

PURPOSE: To analyze macro and microscopic features of atherosclerotic plaques located in bifurcation of coronary arteries, defining their spatial disposition in those sites. METHODS: We studied 38 bifurcations of coronary arteries of patients whose cause of death was related to coronary artery disease. Histologic sections of 0.5mm were sequentially made from the main artery to the secondary branches. They were stained with hematoxilin-eosin technique. Histological analysis evaluated: a) morphologic composition of the plaques, b) degree of obstruction and c) plaque's disposition. RESULTS: a) Plaque's composition: fibrolipid plaques constituted 80% of the cases and mingled focal atrophy of the media at the base of the plaque in 61% with spots of total destruction and rupture of the elastic layers in 30%; b) degree of obstruction: ranged from 20% to 95%, with average 60 +/- 28%; c) disposition of plaques: we verified morphologic variation along the plaque, most of them (71%) being eccentric at bifurcation and not reaching the beginning of flow divider walls. CONCLUSION: Atherosclerotic plaques located in bifurcation of coronary arteries of adults are often fibrolipid plaques, eccentric, and their spatial disposition on those sites spare the beginning of the inner walls, reaching the outer walls.

Adult↗
PubMed1991

Decrease in sulphated glycosaminoglycans in aortic dissection--possible role in the pathogenesis.

STUDY OBJECTIVE: The aim was to investigate alterations in sulphated glycosaminoglycans in aortic dissection. DESIGN: Aortic fragments were taken from 10 patients within the first 3 d after onset of symptoms of aortic dissection and from nine age matched patients with no aortic disease. Sulphated glycosaminoglycans were analysed and quantified by agarose gel electrophoresis and densitometry after degradation with specific enzymes. MEASUREMENTS AND MAIN RESULTS: The amount of chondroitin sulphate was similar (7.14 v 7.60 mg.g-1 of dry tissue, n = 10, p greater than 0.5) in patients with dissection and in the control group. Total sulphated glycosaminoglycan content was decreased (11.51 v 14.26 mg.g-1 of dry tissue, n = 10, p less than 0.001). This difference was due to heparan sulphate (1.79 v 2.48 mg.g-1 of dry tissue, n = 10, p less than 0.05) and mainly to dermatan sulphate (2.58 v 4.18 mg.g-1 of dry tissue, n = 10, p less than 0.001). The ratio of 6-/4-sulphated disaccharides after chondroitinase ABC digestion was increased in the affected group. No correlation between these biochemical results and a histological evaluation of mucoid content was found. On the other hand, a significant increase in chondroitin sulphate could be observed related to aging. CONCLUSIONS: The diminution in sulphated glycosaminoglycans and its possible relationship with fat, collagen, and other extracellular matrix molecules could lead to a weakness in the aortic wall related to the dissection.

Adult↗
PubMed1991

[Mitral valve dysfunction caused by papillary muscle necrosis in patients with anomalous origin of the left coronary artery from the pulmonary trunk].

The clinical evolution of mitral valve disfunction caused by papillary muscle necrosis in patients with anomalous origin of the left coronary artery from the pulmonary trunk was analysed in three children (one 42-day-old male, one five-month-old female and one seven-year-old female). Two patients had been submitted to surgical repair of the anomalous origin of the coronary artery; one of them without mitral repair had a bad evolution in the postoperative period, was reoperated for mitral valve replacement and died two days after surgery. The other patient with plastic of mitral valve had a good outcome. The data indicated that the surgical repair of mitral valve should be provided in cases of mitral valve incompetence secondary to anomalous origin of the left coronary artery from the pulmonary trunk.

Child↗
PubMed1991

[Ligation of the right coronary artery in dogs. Hemodynamic and pathological effects].

PURPOSE: To assess the hemodynamic and pathologic effects of the right coronary artery occlusion in anesthetized dogs submitted to pericardiotomy. METHODS: Ten mongrel dogs were anesthetized with pentobarbital and submitted to a right thoracotomy, pericardiotomy and ligation of the right coronary artery. The pericardium was kept opened throughout the entire experiment. The circulatory pressures and the cardiac output were determined twice before and three times after the right coronary artery ligation. The hearts were then excised, barium was injected in the coronary arteries and radiographs were taken to confirm the artery occlusion. Three dogs were kept alive to later pathologic examination of the hearts. RESULTS: The observation of the radiographs showed proximal occlusion of the right coronary artery and absence of the right ventricle free wall vascularization. There was ischemic necrosis of about three quarters of this area, whereas the septum was normal. The cardiac index and the systemic mean arterial decreased 14% without significant variation of the central venous and the pulmonary artery pressures, although marked right ventricular dilation was observed. CONCLUSION: The proximal right coronary artery ligation in the dog determines ischemia and infarction of the right ventricular free wall, without affecting the interventricular septum. There are few hemodynamic consequences with open pericardium and at rest.

Animals↗
PubMed1990

[Fatal acute myocardial infarction in a young cocaine addict].

A 28 year-old male cocaine abuser without coronary atherosclerosis suffered fatal myocardial infarction. Necropsy revealed several myocardial infarctions of different ages. Examination of the coronary arteries revealed fibrointimal thickening of the intimal layer of the coronary arteries.

Adult↗
PubMed1990

[Differences between men and women in fatal cases of myocardial infarction: study of 200 necropsies].

PURPOSE: To compare morphological characteristics from myocardial infarction (IM) in men and women in 200 consecutive necropsies. MATERIAL AND METHODS: Necropsy heart findings from 62 female cases compared with those from 138 male cases, from patients who died from transmural myocardial infarction. Age ranged from 21 to 82 (mean 60) years. RESULTS: Concerning the coronary arteries, the number of 3 major (right, left anterior descending and left circumflex) epicardial coronary arteries narrowed at some point greater than 70% in cross-sectional area by atherosclerotic plaque was not significantly different; on the other hand, there were more severe lesions in the left main coronary artery in men (10.33%) than in women (1.64%) (p = 0.050). 33.33% of men and 43.55% of women had only recent myocardial infarction (1 month or less); 33.33% of men and 14.52% of women had only old myocardial infarction (more than 1 month); 33.33% of men and 41.94% of women had both recent and old myocardial infarction. 12.90% of women and 2.17% of men showed rupture of the left ventricle (p = 0.0220). 15.22% of men and 6.45% of women had left ventricular aneurysms (p = 0.830). CONCLUSION: There are more deaths during the acute phase of MI, in the first infarction and from rupture of the left ventricle in female patients; in men, there are more deaths occurring in chronic phases of the disease and with previous myocardial infarction; and more severe narrowing from the left main coronary artery.

Adult↗
PubMed1989

[The biopsy in the diagnosis of pericardial involvement by malignant tumor].

We performed pericardial biopsy by subxiphoid approach in twelve patients (eight men, four women) with cardiac tamponade or pericardial effusion without low cardiac output, in order to search for the underlying disease. Five patients (41%) had pericardial biopsy with malignant neoplastic invasion. In seven patients (59%) the biopsy was nonspecific; in these patients, the diagnosis was made by another methods. We concluded that the pericardial biopsy is a safe method, with high especificity but low sensibility in the diagnosis of malignant pericardial invasion.

Biopsy↗
PubMed1989

[Right ventricular dysplasia associated with Ebstein type malformation of the tricuspid valve. A case report].

Right ventricular dysplasia, also named right ventricular cardiomyopathy, cardiac lipidosis and partial absence of the right ventricular myocardium, is an uncommon disease in which the myocardium is partially replaced by fat and fibrous tissue. The clinical picture is usually characterized by complex arrhythmias, causing sudden death in adolescents and young adults, and cardiac failure. In this report, an association between this disease and "Ebstein-type" tricuspid valve malformation has been diagnosed in a 22 year old female patient with cianosis and dyspnea on exertion.

Adult↗