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E Arbustini

Publications and source records attributed to E Arbustini.

At least 109 records · Page 6Linked to original sources
PubMed1995

Human heart mast cells. Isolation, purification, ultrastructure, and immunologic characterization.

We have isolated, partially purified, and characterized the mast cells from human heart tissue. The histamine content of left and right ventricles and septum of hearts obtained from 25 patients undergoing heart transplantation was 5.4 +/- 0.6, 5.3 +/- 0.5, and 5.6 +/- 0.5 micrograms/g of wet tissue, respectively. Ultrastructural study of cardiac mast cells revealed scroll, crystal, and mixed granules, homogeneously dense granules, and lipid bodies in the cytoplasm. A mild collagenase digestion was used to disperse the heart mast cells; the average yield was 3.2 +/- 0.6% (range: 0.8 to 13.6%). The average histamine and tryptase content/heart mast cells was 3.3 +/- 0.2 pg (n = 25) and 24.2 +/- 4.3 micrograms/10(6) cells (n = 11), respectively. Survival of cardiac mast cells after overnight culture was 71.9 +/- 5.4% (n = 23). The purification of human heart mast cells can be brought from less than 0.1 to 12% by a combination of low-speed centrifugation over albumin (2%) solution and Percoll gradient. Viability as shown by trypan blue exclusion was greater than 90%. Heart mast cells released histamine in response to immunologic (anti-IgE, anti-Fc epsilon RI, and C5a) and nonimmunologic stimuli (recombinant human stem cell factor, A23187, and compound 48/80) but did not respond to substance P, FMLP, 12-O-tetradecanoylphorbol-13-acetate, or acetylcholine. There was a linear correlation between the percentage of release caused by anti-IgE and anti-Fc epsilon RI, whereas there was no correlation between the release caused by C5a and anti-IgE-mediated stimuli. Cross-linking with anti-IgE of IgE on heart mast cells induced the release of tryptase (10.1 +/- 2.1 micrograms/10(7) cells; n = 10) and the de novo synthesis of PGD2 (17.3 +/- 4.3 ng/10(6) cells; n = 10) and of leukotriene C4 (19.1 +/- 4.5 ng/10(6) cells; n = 10). There was a linear correlation between the percentage of histamine secretion and tryptase release (r = 0.67; p < 0.001) induced by cross-linking of Fc epsilon RI. similarly, there was a significant correlation between percentage of histamine secretion and PGD2 (r = 0.63; p < 0.001) and LTC4 (r = 0.64; p < 0.001) release. Immunoelectron microscopy demonstrated the presence of chymase in cardiac mast cells. Mast cells isolated from human heart can be a useful model with which to study the role of these cells and their mediators in cardiac anaphylaxis and cardiovascular diseases.

Cell Separation↗
PubMed1995

Leber's hereditary optic neuropathy (LHON)-related mitochondrial DNA sequence changes in italian patients presenting with sporadic bilateral optic neuritis.

Eighteen Italian patients presenting with sporadic, bilateral, simultaneous, or sequential optic neuritis (ON) were evaluated for 14 base changes in mitochondrial DNA (mtDNA) previously found associated with Leber's hereditary optic neuropathy (LHON), aiming to identify at a molecular level LHON cases with nontypical phenotypes. During a 36-month follow-up, 11 ON patients developed clinical or laboratory features allowing diagnosis of clinically definite multiple sclerosis (MS). None was positive for any of the "primary" LHON-associated mutations. However, single or multiple "secondary" LHON-associated sequence changes at 4216/ND1, 4917/ND2, and 13708/ND5 were detected in ON and ON-MS patients. MS controls without visual failure as well as healthy control subjects harbored the same base changes at similar frequencies. In addition, coexistence of three sequence changes was found in two cases (1 ON-MS patient and 1 MS control patient). We also report finding two new neutral sequence base changes in the ND-4 gene which were identified by SSCP and confirmed by automated DNA sequence analysis. The results suggests that these secondary mutations do not contribute to MS susceptibility in these patients, but rather represent neutral mitochondrial DNA polymorphisms. In addition, whether there are biochemical abnormalities related to single and multiple secondary mtDNA sequence changes remain to be demonstrated.

Adult↗
PubMed1995

Cardiac immunocyte-derived (AL) amyloidosis: an endomyocardial biopsy study in 11 patients.

The objective of this study was to investigate the spectrum of morphologic features in myocardial biopsy specimens from patients with cardiac immunocyte-derived (AL) amyloidosis. Cardiac involvement is the most important predictor of survival in AL amyloidosis. Myocardial biopsy remains the method of choice for diagnosing cardiac amyloidosis when noninvasive studies give equivocal results. Histologic, immunohistochemical, ultrastructural, and morphometric studies were made on myocardial biopsy specimens from 11 patients in whom the diagnosis of AL amyloidosis was based on the demonstration of a monoclonal immunoglobulinopathy and of amyloid deposits in tissues. Histopathologic study showed amyloid in 10 of the 11 biopsies. In one biopsy (Congo red negative), the diagnosis was made by ultrastructural identification of amyloid fibrils. In all patients, the deposits formed perimyocytic layers that measured up to 18 microns in thickness. These layers formed along the basement membranes, which were partially preserved in 5 patients and unrecognizable in 6. Interstitial nodular deposits were also present in 5 patients. Immunohistochemical studies for the characterization of the proteins in the amyloid deposits were diagnostic in 1 patient and confirmatory in 10. Nodular deposits, thick perimyocytic layers of amyloid and small myocyte diameters were associated with shorter survival of the patients. Small-vessel involvement and myofilament loss occurred in all patients. In conclusion, myocardial biopsy serves to (1) establish the diagnosis of cardiac amyloidosis; (2) characterize immunohistochemically the proteins in the amyloid fibrils and (3) assess the degree of myocyte damage and atrophy.

Adult↗
PubMed1995

Immunological characterization and functional importance of human heart mast cells.

Mast cells are present in normal and even more abundant in diseased human heart tissue and their localization is of particular relevance to their function. Within heart tissue mast cells lie between myocytes and in close contact with blood vessels. They are also found in the coronary adventitia and in the shoulder regions of a coronary atheroma. The density of cardiac mast cells is markedly higher in some patients with myocarditis and dilated cardiomyopathy than in accident victims without cardiovascular diseases. More importantly, in some of these conditions there is in situ evidence of mast cell activation. We have described an original technique to isolate and purify HHMC for in vitro study. This procedure gives viable cells and after stimulation with immunological or non-immunological stimuli they release performed (histamine and tryptase) and newly generated mediators (PGD2 and LTC4). We have demonstrated that HHMC differ from those in other anatomical districts in that they are activated by specific immunological and non-immunological stimuli, and in their relation to the arachidonic acid metabolism, suggesting that the local microenvironment can influence their phenotypic and biochemical characteristics. Our own and other findings suggest that HHMC have complex and significant roles in different pathophysiological conditions involving the cardiovascular system. Direct activation of HHMC by therapeutic and diagnostic substances injected intravenously explains some of the anaphylactoid reactions caused by these agents. HHMC possess Fc epsilon RI and IgE bound to the surface and C5a receptors, which could explain how cardiac mast cells are involved in systemic and cardiac anaphylaxis. Cardiac mast cells and those in human coronary arteries also play a role in the early and late stages of atherogenesis and during ischemic myocardial injury. In conclusion, although studies of HHMC are in their infancy, their in vitro isolation may be useful in identifying additional mediators synthesized and released, stimuli relevant to human pathophysiology, and pharmacological agents selectively modulating the activation of these cells and their mediators. Drugs specifically acting on HHMC or on their mediators may eventually be useful in treating different cardiovascular diseases.

Anaphylaxis↗
PubMed1995

Angiotensin converting enzyme gene deletion allele is independently and strongly associated with coronary atherosclerosis and myocardial infarction.

OBJECTIVE: To investigate the association of the three angiotensin converting enzyme (ACE) genotypes, DD, ID, and II, with the occurrence or absence of coronary atherosclerosis and with myocardial infarction and hypertension. DESIGN: Cohort analysis study. SETTING: North-Italy reference centre. SUBJECTS: 388 white Italian patients (281 males; mean age 60.7 (SD 12.5) years) with proven coronary atherosclerosis (n = 255) or with angiographically normal coronary arteries (n = 133). A further group of 290 healthy blood donors was tested for allele frequency comparison. INTERVENTIONS: ACE/ID polymorphism was analysed with polymerase chain reaction on DNA from white blood cells. MAIN OUTCOME MEASURES: Coronary atherosclerosis, myocardial infarction, hypertension. RESULTS: The D and I allele frequencies were respectively 0.63 and 0.37 in the overall healthy blood donor group and 0.66 and 0.34 in the overall study group. In the latter, univariate analysis showed (1) that coronary atherosclerosis (255 patients) was associated with the deletion allele, with an odds ratio (OR) of 5.78 for DD/II, P < 0.001, and 2.39 for ID/II, P = 0.006; and (2) that myocardial infarction (154 patients) was associated with the DD genotype (OR DD/II = 2.56, P = 0.007), but not with the ID genotype (OR DD/II = 1.96, P = 0.056). Finally, hypertension proved to be unrelated with the ACE genotype. The distribution between the three genotypes of known risk factors for coronary artery disease was similar. Logistic regression modelling, performed to test the association of the selected risk factors simultaneously with coronary atherosclerosis and myocardial infarction, showed that the deletion allele (whether DD or ID) was the strongest risk factor for atherosclerosis, and that the D allele was significantly associated with the risk of infarction (although to a lesser extent than with coronary atherosclerosis). CONCLUSION: ACE deletion polymorphism is strongly and independently associated with coronary atherosclerosis and, to a lesser extent, with myocardial infarction. As such, the results are analogous to what has already been reported in French white, Japanese, and Welsh coronary patients.

Adolescent↗
PubMed1995

Successful reduction of endomyocardial fibrosis in a patient with idiopathic hypereosinophilic syndrome. A case report.

A case of endomyocardial fibrosis in a patient with idiopathic hypereosinophilic syndrome is reported and discussed. The authors draw attention to the importance of both echocardiography (two-dimensional and Doppler) and nuclear magnetic resonance in the detection of cardiac involvement due to this rare pathology. Moreover, these imaging techniques appear to be valuable in the evaluation of effects of medical treatment. Therapy with corticosteroids alone has shown no reliable effectiveness in reducing the absolute eosinophil count. A combined immunosuppressive treatment with use of hydroxyurea is required.

Dipyridamole↗
PubMed1994

Cytogenetic studies in venous tissue from patients with varicose veins.

Cytogenetic investigation of primary cell cultures from fragments of varicose veins of seven patients with familial varicosity and seven patients with the sporadic type revealed the presence of metaphases with structural abnormalities, clonal trisomies of chromosomes 7, 12, and 18, and monosomy of chromosome 14 only in cases with the familial type, while the sporadic cases had no similar chromosome aberrations. The immunophenotypical results are consistent with fibroblast lineage of the cultured cells. These results suggest that karyotypic variations in familial varicose vein tissue cultures could in some way be associated either with the genotypic constitution responsible for the familial type or a longer duration of disease on average than those with sporadic varicosities.

Adult↗
PubMed1994

Reversal of nephrotic syndrome due to reactive amyloidosis (AA-type) after excision of localized Castleman's disease.

The patient (TAL), a chronic asymptomatic HBV carrier with HBsAg-anti-HBsAg circulating immune complexes, was admitted to our hospital because of a nephrotic syndrome due to renal amyloidosis. There was no family history of hereditary amyloidosis. Recurrent arthralgias, asthenia, and weight loss were the prominent clinical features. Laboratory test results showing that severe chronic inflammatory activity had been present for 6 years. Interleukin-6 (IL-6) serum concentration was 10 times normal and C-reactive protein was 1.9 mg/ml. A complex immunological picture was also present (immune complex formation, exuberant B-cell reactivity, and decrease in the number of CD4 T cells). A localized form of Castleman's disease (CD) (plasma-cell type) was diagnosed by surgical excision of a giant axillary lymph node. AA amyloid was present in the blood vessels. Within 60 days after excision of the mass, the systemic symptoms subsided, laboratory signs of inflammatory activity disappeared and IL-6 serum concentration returned to normal, thus establishing a causal relationship between the localized Castleman's disease, elevated IL-6 concentration and the chronic inflammation responsible for AA amyloidosis. At 10 months of follow-up, the nephrotic syndrome has reversed, kidney function has slowly ameliorated, and the patient has gained 12 kg. Abdominal fat aspirates drawn to search for amyloid, positive before surgery, were subsequently negative. The latter finding, and the remission of the nephrotic syndrome, provided strong evidence for regression of the amyloid deposits. However, the HBsAg-anti-HBsAg immune complexes and depression of T-helper cell activity persist. This immunological derangement is therefore not a consequence of CD. Chronic stimulation of the immune system due to the patient's inability to eliminate HBV, in the contest of perturbed immunity, may have favored the genesis of the lymphadenopathy.

Adult↗
PubMed1994

Dilated cardiomyopathy requiring cardiac transplantation as initial manifestation of Xp21 Becker type muscular dystrophy.

A neurologically asymptomatic 32-yr-old man recently transplanted for end-stage dilated cardiomyopathy presented with progressively increasing serum creatine kinase level (hyperCKemia) while receiving cyclosporin and simvastatine treatment. Revised family history led to suspicion of X-linked inherited myopathy, then confirmed by muscle biopsy findings showing myopathic dystrophic changes, a patchy distribution of immunoreactivity on the sarcolemma of several muscle fibres with anti-dystrophin antibodies and a double dystrophin band of normal and lower molecular weight on immunoblot analysis. A molecular genetic study demonstrated a deletion spanning over exons 45-47 at Xp21 locus. Routine neurological evaluation and currently available laboratory investigation may lead to early diagnosis of otherwise unrecognized Xp21 BMD among patients presenting with dilated cardiomyopathy alone, thus avoiding subsequent diagnostic difficulties.

Adult↗
PubMed1994

[Diagnostic and research potential of directional atherectomy].

Directional coronary atherectomy (DCA) is the sole technique for the in vivo study of coronary artery plaques which are responsible for myocardial ischemia. The technique confers the following advantages to the pathologic study of plaque samples: the brevity, in general, of the interval between acute myocardial ischemia and sampling of the guilty plaque; the absence in samples of autolytic phenomena (such as those that affect autopsy samples), an effect that enables the use of conventional histopathology, immunohistochemistry and molecular biology; the certainty with which the researcher can identify, and thus sample, the truly guilty lesions. The drawbacks of the technique are: the fragmentation of the plaque; the difficulty the pathologist has in correctly orientating the samples in the embedding phase, in distinguishing pre- from post-procedural lesions, and in providing a detailed description of the findings. Given the foregoing, the diagnostic information to which DCA sampling enables access is as follows: plaque derivation--the recognition of whether tissue removed with DCA originates from eccentric or concentric, atheromatous of fibrosclerotic, calcified or not calcified plaques; histopathology of coronary lesions that cause ischemia with regard to: evidence of acute events, such as thrombosis, ulceration and hemorrhage, thrombus composition, when it occurs, and definition of its age and presence of material deriving from the vascular wall that lies beyond the plaque; identification and immunophenotypical characterization of inflammatory infiltrates. As regards research, the main implications of DCA are for the study of the pathogenetic mechanisms that lead to plaque instability in acute ischemic syndromes.(ABSTRACT TRUNCATED AT 250 WORDS)

Atherectomy, Coronary↗
PubMed1994

Embolizing fibroelastoma of the aortic valve.

Papillary fibroelastomas are very rare cardiac tumours that can present with embolization of coronary and peripheral arteries and sudden death. The diagnosis can be made by two-dimensional or transoesophageal echocardiography. A 53-year-old man with an aortic valve papillary fibroelastoma who presented with several transient ischaemic attacks is reported.

Aortic Valve↗
PubMed1994

Coexpression of aspartic proteinases and human leukocyte antigen-DR in human transplanted lung.

Aspartic proteinases have recently been shown to be implicated in antigen processing. We explored the expression of two aspartic proteinases, cathepsins E and D, and of human leukocyte antigen-DR (HLA-DR) molecules in a consecutive series of 80 transbronchial biopsies from transplanted lungs. For controls, we studied five normal donor lungs (not suitable for transplantation on account of thoracic trauma) and macroscopically normal areas of three cancer-affected lungs. Two of the five unsuitable donor lungs showed minimal inflammatory changes. Macroscopically normal samples from the three cancerous lungs showed mild and focal inflammatory infiltrates. In histologically normal lungs, HLA-DR expression was limited to professional antigen-presenting cells. Macroscopically normal lung samples with minimal inflammatory changes from both donor and cancer lungs showed variable HLA-DR expression by alveolar and bronchial epithelial cells and by endothelial cells. All transplanted lung biopsies showed HLA-DR expression by epithelial (alveolar and bronchial) and endothelial cells, with a trend for increased positivity in acute rejection. Cathepsin E was restricted to Clara and to rare bronchus-associated lymphoid tissue-related epithelial cells in histologically normal lung samples, whereas minimal de novo cathepsin E expression by rare alveolar pneumocytes was noted in control lung samples exhibiting minimal inflammatory changes. In all transplanted lung biopsies, cathepsin E was diffusely expressed de novo by hyperplastic alveolar epithelial cells, regardless of the presence or degree of rejection. Cathepsin D was expressed only by alveolar macrophages and by ciliated bronchial cells of normal, minimally inflamed, and transplanted lungs. In transplanted lung, Clara cells and several hyperplastic alveolar pneumocytes coexpressed HLA-DR and cathepsin E, whereas all alveolar macrophages and a few ciliated cells coexpressed cathepsin D and HLA-DR. The present investigation suggests that the de novo expression of cathepsin E and HLA-DR by hyperplastic alveolar pneumocytes of transplanted lung may be crucial for antigen processing and presentation to recipient competent T cells, and thus for the triggering of the immune-inflammatory cascade that leads to rejection.

Acute Disease↗
PubMed1993

Expression of proliferating cell markers in normal and diseased human hearts.

Proliferating cell nuclear antigen (PCNA) myocyte expression and histopathologic features related to its occurrence were investigated in normal and diseased hearts of adult humans using both immunohistochemical and Western blotting techniques. Ki67 Western blotting was also performed in the same samples used for PCNA blotting. Two hundred seventy-one endomyocardial biopsies, and 15 adult, 1 embryonic and 2 fetal hearts were studied. The biopsies were from normal donor hearts (n = 71), patients with cardiomyopathy and myocarditis (n = 64), and patients with transplantation with (n = 106) and without (n = 30) acute rejection of any grade. The 15 hearts were from 1 heart donor, and from patients with cardiomyopathy (n = 5), valvular heart disease (n = 2), ischemic heart disease (n = 4), amyloidosis (n = 1) and transplantation with acute rejection (n = 2). The PCNA labeling index was plotted against myocyte hypertrophy, inflammatory infiltrates and binucleation index. The PCNA labeling index ranged from 2 to 9% in embryonic and fetal hearts. PCNA was expressed by 1 to 2% of myocyte nuclei in 12% of normal heart biopsies, 1 to 5% of myocyte nuclei in 28% of cardiomyopathy and myocarditis biopsies, and by up to 8% of myocyte nuclei in 53% of biopsies of patients with transplantation, independently of the presence and degree of acute rejection. In the latter biopsies and in myocarditis, some inflammatory cells also showed PCNA expression. PCNA positive myocytes were both mono- and binucleated, and there was no correlation between binucleation and PCNA labeling indexes. Ki67 and PCNA blotting confirmed immunohistochemical results.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Morphologic changes induced by acetylcholine infusion in normal and atherosclerotic coronary arteries.

Low doses of acetylcholine induce "endothelium-dependent" dilatation in normal coronary arteries and constriction of diseased vessels. This study investigated morphologic changes induced by perfusion of normal and diseased coronary arteries with low and high doses of acetylcholine. Vessels were excised from a series of beating hearts explanted at transplantation for idiopathic dilated cardiomyopathy and coronary artery disease. Coronary arteries from other explanted hearts, perfused with saline solution under similar conditions were taken as controls. Samples were studied using conventional histopathologic and immunohistochemical methods. Coronary arteries were grouped according to presence or absence of histologically detectable structural modifications of any type and extent. Low doses of acetylcholine induced changes in all but 1 structurally diseased coronary artery, whereas no change was induced in any but 1 histologically normal coronary artery. High doses of acetylcholine induced contraction changes in both normal and diseased vessels. Changes observed in the wall of the contracted vessels were: (1) endothelial cell contraction with protruding nuclei and detachment of their intercellular junctions with exposure of subjacent collagen to flow, (2) contraction of plaque smooth muscle cells, (3) formation of cushions protruding into vessel lumens causing blunt microchannels. Contraction in both intimal and plaque cells occurred even in diseased vessel segments with intimal denudation. These effects seemed to be dose-dependent in structurally normal vessels because low doses of acetylcholine did not produce any morphologically detectable changes in histologically normal coronary arteries, while low doses of acetylcholine induced similar reactions in vessels affected by both atherosclerosis and subintimal fibrocellular thickening.

Acetylcholine↗