H and L ferritins in myocardium in iron overload.
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
M Diegoli
Publications and source records attributed to M Diegoli.
Coronary atherosclerotic plaques with and without thrombus in ischemic heart syndromes: a morphologic, immunohistochemical, and biochemical study.
We investigated incidence, severity, and distribution of coronary atherosclerosis, acute thrombosis, and plaque fissuring in ischemic heart disease (both unstable-acute syndromes and chronic ischemia) and in nonischemic controls. We also studied the structural, immunohistochemical, and biochemical profile of plaques, with and without thrombus, including morphometry, immunophenotyping of inflammatory infiltrates, cytokine presence, and ultrastructural features. Critical coronary stenosis was almost the rule in both acute and chronic ischemic series (greater than 90%) whereas it reached 50% in control subjects. Thrombosis was principally characteristic of unstable-acute ischemic syndromes (unstable angina, 32%; acute myocardial infarction, 52%; cardiac sudden death, 26%) but was also found in chronic ischemia (stable angina, 12%; ischemic cardiomyopathy, 14%) and in control subjects (4%). Plaque fissuring without thrombus occurred in low percentages in lipid-rich, severe eccentric plaques in most series. Major differences were found between pultaceous-rich versus fibrous plaques rather than between plaques with or without thrombus. Pultaceous-rich plaques were frequent in sites of critical stenosis, thrombosis, and ulceration. Inflammatory infiltrates, i.e., T cells, macrophages, and a few beta cells, mostly occurred in lipid-rich, plaques unrelated to thrombus. In adventitia, infiltrates were a common finding unrelated to any syndrome. Necrotizing cytokines such as alpha-TNF were immunohistochemically detected in macrophages, smooth muscle, and intimal cells and detected by immunoblotting in 67% of pultaceous-rich plaques, either with or without thrombus. Immune response mediators such as IL-2 were also expressed in analogous plaques but in a minor percentage (50%-40%). Media were extensively damaged in severely diseased vessels with and without thrombus. Ultrastructural study showed that the fibrous cap was either highly cellular or densely fibrillar. Intimal injury with collagen exposure was often associated with platelet adhesion, whereas foamy cell exposure was not. In conclusion, investigated parameters were essentially similar in plaques, both with and without thrombus, whereas major differences were found between pultaceous-rich and fibrous plaques. Since platelets adhere to exposed collagen and not to foam cells, the type of exposed substrates could play a major role in thrombosis.
Adult↗
Atrial amyloid deposits in the failing human heart display both atrial and brain natriuretic peptide-like immunoreactivity.
Atrial amyloid deposits are common in the ageing human heart and contain alpha-atrial natriuretic peptide (proANP99-126) immunoreactivity. However, atrial myocytes secrete both amino and carboxy terminal fragments of the ANP prohormone (proANP1-126) and also express an homologous, but separate brain natriuretic peptide (BNP). Characteristic amyloid deposits were identified in the atria of 9/22 patients (26-63 years of age) with end-stage heart failure. Amyloid fibrils displayed immunoreactivity for both amino and carboxy terminal fragments of proANP1-126 and for the distinct BNP sequence. As in other endocrine organs, both mature and precursor peptide sequences appear to be constituents of amyloid fibrils. Whilst immunoreactivity for cardiac peptide hormones is co-localized in atrial amyloid deposits, it is uncertain whether the increase in natriuretic peptide expression which accompanies cardiac failure contributes to the incidence of isolated atrial amyloidosis.
Adolescent↗
[Endomyocardial biopsy in the heart transplant patient: the state of the art].
Data regarding 2176 endomyocardial biopsies (EMB) (Nov. '85-Dec. '89) performed in 164 transplanted hearts (4 etherotopic) from 158 patients (6 retransplants) are herein reported. This study was aimed to evaluate: 1) Incidence and characteristics of early ischemic myocardial damage. 2) The influence of different immunosurveillance protocols on incidence, degree and aggressiveness of acute rejection and the inflammatory infiltrate composition. 3) The immunophenotype of infiltrating cells in moderate acute rejection episodes. 4) HLA-DR antigen expression on myocyte sarcolemma. 5) Characterization of cells expressing immune response mediators. 6) Myocardial localization of opportunistic infections. 7) Useful information on chronic rejection. Our results demonstrate that: a) Mild rejection seldom progresses to moderate degree. b) Different immunosuppressive protocols can influence the incidence of acute rejection: in fact, in OKT3 protocol, the incidence of rejection episodes is higher than in other protocols as well as aggressiveness toward myocytes. c) Infiltrating cells maintain T lymphocyte prevalence with minor amounts of B lymphocytes and macrophages in the 3 different protocols. T cell subset characterization showed a slight prevalence of CD8 bearing cells over CD4 positive cells whereas CD57 cells were few and scattered. d) Class II Major Histocompatibility Complex (HLA-DR) expression never occurs on myocyte sarcolemma. e) TNF alpha is expressed in acute cardiac rejection by immunologically activated T lymphocytes and macrophages and the number of immunoreactive cells increases with progression of the rejection. f) Human cytomegalovirus infections can be primary or recurrent. Myocardial involvement has been observed in primary forms. Virus can affect endothelial cells (with no inflammatory reaction) or myocytes (myocarditis) and its diagnosis requires a combination of immunohistochemical and molecular biology techniques. Diagnosis of Toxoplasma gondii infection can be usually accomplished by routine histopathological study. g) Chronic rejection diagnosis is rarely based on biopsy derived information.
Biopsy↗
Expression of tumor necrosis factor in human acute cardiac rejection. An immunohistochemical and immunoblotting study.
The authors performed an immunohistochemical study on expression of tumor necrosis factor alpha (TNF alpha) in endomyocardial biopsies from human cardiac allografts. TNF alpha immunoreactivity was found in 45% biopsies with mild acute rejection, in 83% biopsies with focal moderate rejection, in 80% biopsies with diffuse moderate rejection. Biopsies with absent rejection did not show immunoreactive cells. In mild rejection, positive cells were few and scanty monocytes and macrophages (MAC-387 and LN5 positive cells) and T lymphocytes (UCHL-1/CD45 RO positive cells) (up to 20% of all infiltrating cells). Expression of major histocompatibility complex (MHC) class II antigens on infiltrating and endothelial cells occurred earlier and independent of TNF alpha reactivity. Number of immunoreactive cells increased in moderate rejection (up to 50%). Immunoreactivity was also present in nonpigmented macrophages in part of the biopsies with resolving rejection (45%). The authors conclude that TNF alpha is expressed in acute cardiac rejection by immunologically activated inflammatory cells. Immunoreactive cells increase in number with increasing severity of the reaction.
Biopsy↗
Expression of natriuretic peptide in ventricular myocardium of failing human hearts and its correlation with the severity of clinical and hemodynamic impairment.
Atrial natriuretic peptide (ANP) was immunohistochemically investigated in (1) right ventricular endomyocardial biopsy specimens from 87 apparently healthy donor hearts taken from victims of cerebral accidents; (2) 1 normal heart not suitable for transplantation (HBsAg carrier); (3) right ventricular endomyocardial biopsy specimens from 151 patients with dilated cardiomyopathy (DC); and (4) 57 explanted hearts, 26 with DC and 31 with ischemic heart disease. No ANP immunoreactivity was found in normal ventricles. Failing hearts showed ventricular positivity in 31% of the DC biopsy series, in 61% of the left ventricles, and in 30% of the right ventricles of the explanted heart series. An endoepicardial gradient was observed, because ANP positivity was greater and more extensive in the subendocardial layers. Ultrastructural studies were performed on biopsy specimens from 10 normal hearts and 132 DC biopsy samples. No ANP-storing granules were found in biopsy samples of normal ventricles, whereas ANP granules were seen in 15 of 132 (11.4%) DC cases. In parallel immunoblotting, investigation showed the same 13 kDa band protein in 1 normal atrium as well as in 8 failing atria and ventricles. ANP immunoreactivity was positively correlated with higher New York Heart Association functional classes as well as with higher left ventricular end-diastolic pressure (p less than 0.005), end-diastolic volume (p less than 0.005) and end-diastolic volume index (p less than 0.005). In conclusion, apparently healthy ventricles do not show ANP immunoreactivity, whereas failing ventricles do. ANP expression seems to be independent of the underlying disease, but positively related to the clinical status and the degree of left ventricular impairment and dilatation.
Adult↗