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Biomedical subjects

L Rossi

Publications and source records attributed to L Rossi.

At least 217 records · Page 12Linked to original sources
PubMed1995

Structural and non-structural disease underlying high-risk cardiac arrhythmias relevant to sports medicine.

Problems of arrhythmogenic sudden death (ASD) in athletes have been re-assessed on the clinicopathological plane, encompassing the emerging, unsolved, question of so-called idiopathic ventricular tachycardia, and its debated diagnostics versus arrhythmogenic right ventricular dysplasia-cardiopathy. Ischemic-infarction ASD from coronary artery pathology in young athletes has been seen to present with atherosclerotic "soft" subintimal plaques, rich in newly formed smooth myocytes, often attended by adventitial mast cell, as suspect microscopic markers of spasm, relevant to reperfusion; these features can be found also in precociously intramural arteries, responsible for ASD. Rare congenital abnormalities of the coronary ostia occasionally underlie ASD, together with the acquired aneurysmic coronaritis of chronic Kawasaki disease. Ischemic ASD can also be due to coronary arteriolopathy attending hypertrophic cardiomyopathy, a not uncommon disease in athletes, to be carefully discriminated from training heart hypertrophy. Young South-American sportsmen with Chagas' chronic cardiopathy seem to be at particular risk of ASD. Minor, but specific arrhythmogenic cardiac malformations such as accessory AV pathways have been detected in athletes succumbing to otherwise unexplained ASD, undergone careful post-mortem investigation. The need of more attentive and extended histopathologic control emerges from the hitherto ignored cardiac neuropathological substrates of reflexogenic ASD, which is cogent to problems of ASD in competing athletes. The thorough examination of the cardiac vascular centers in the brain stem, and of the peripheral cardiac innervation, at either abutments of the arc of dive- and/or Bezold-Jarisch cardioinhibitory-vasodepressor reflex, made it possible to suggest novel clinicopathological explanations in controversial cases of athletes' ASD, safeguarding from grave leval misjudgements due to sport's forensic medical mistakes.

Arrhythmias, Cardiac↗
PubMed1995

[Ventricular tachycardia secondary to myocardial contusion in an athlete: a clinical case report].

A 22-year-old athlete complained of palpitations shortly after a chest trauma during a basket competition. His electrocardiogram showed a ventricular tachycardia of 250 beats per minute, reverted to sinus rhythm with a chest thump. Standard electrocardiogram was normal. The following days he had an enzymatic pattern consistent with acute myocardial infarction, and the echocardiogram evidentiated an apical hypokinesia with a mural thrombosis. The patient recovered completely; and 15 days after the acute event, a coronary arteriography and ventriculography did not revealed any abnormality.

Adult↗
PubMed1995

[An epidemiological survey of cardiovascular disease risk factors in 18-year-old males during their medical check-up at an Army recruiting center in the province of Verona].

Between January and December 1992 an epidemiological survey on the risk factors for cardiovascular disease in eighteen-year old boys during call-up has been performed in Verona. The study involved 3426 subjects: 100% of the boys coming from the metropolitan area and 65% of those coming from the non-metropolitan areas. A family history of hypertension was found in 9.54% of the subjects and a family history of myocardial infarction or sudden death was found in 4.54% of the subjects. 0.18% of the population reported diabetes and 2% hypertension. Prevalence of smoke addiction was 39.1% and in this group 17.54% smoked > or = 20 cigarettes/day. Prevalence of smoke addiction was significantly greater in the boys having one or both smoking parents (p < 0.001), in working people in respect to students (p < 0.001), in boys from metropolitan in respect to those from non-metropolitan areas (p = 0.033), and among those not practising sport activity (p < 0.001). Mean systolic and diastolic blood pressure were 130.16 +/- 13/74.48 +/- 9 mm Hg and 90th percentile was 149/87 mm Hg. Systolic and diastolic blood pressure were significantly lower in boys from metropolitan in respect to those from non-metropolitan areas and in smokers in respect to non smokers. A body mass index > or = 30 was found in 3.04% of the subjects, the body mass index being directly related to systolic and diastolic blood pressure (p < 0.001). Total cholesterol performed on a voluntary basis from capillary blood samples by Reflotron System was determined in 80.06% of the subjects. Mean blood cholesterol was 139.1 +/- 28 mg/dL and 90th percentile's value was 182 mg/dL. Mean blood cholesterol was significantly lower in non-metropolitan in respect to metropolitan areas (p = 0.033). 44.48% of the subjects had one or more risk factors, 5.22% had two risk factors and 0.67% three or more risk factors for cardiovascular disease. This study shows that 1) in this population of young people a significant part is exposed to one or more cardiovascular risk factors; 2) social and environmental factors affect, sometimes deeply, the prevalence of cardiovascular risk factors; 3) The visit for call-up appears to be important in the setting-up of a strategy of primary prevention for cardiovascular disease.

Adolescent↗
PubMed1995

[Assessment of lead blood levels in children living in Lucca (Italy) in 1993. The study was conducted as part of the project METOS, in accordance with the decree 496 of June 1982 which adopted the directive CEE No.77/312].

OBJECTIVE: Lead poisoning is a major cause of environmental concern in all countries worldwide. Saturnism in children, especially if young and neglected, represents a peculiar phenomenon both in terms of the biology of growing subjects and the epidemiological nature of poisoning. In under five-year-olds, in addition to lead levels in the atmosphere, it is equally important to evaluate the presence of contaminated dust in the house, hand-to-mouth activities and the level of care provided by parents. It has been demonstrated that, in the presence of equivalent environmental lead levels, dust removal from the house and prevention of hand-to-mouth activities can successfully reduce lead blood levels (PbB) in children. AIM: The aim of this study was to evaluate the risk of chronic lead poisoning in children attending Local Health Unit 6 in Piana di Lucca and to assess the need for a possible health education campaign aimed at eliminating the specific pediatric risk for lead poisoning. MATERIALS AND METHODS: Assay of lead blood levels in 172 children from 0 to 14 years old consecutively attending the Emergency Ward at Campo di Marte Hospital in Lucca for reasons not relating to lead poisoning. RESULTS: Mean lead blood levels in children were 57.2 +/- 30.2 mg/l (mean 50 mg/l) without significant differences between the various age brackets (0-5, 6-10, 11-14 years old). Only one child presented pathological PbB levels (280 mg/l when first measured; 360 mg/l a few months later with normal values of erythrocytic Zn-protoporphyrin, 24-h urinary lead excretion and 24-h urinary delta-aminolevulinic acid). An epidemiological study is now being made of the causes. The general population within the same area presented mean PbB levels of 70.4 +/- 36.9 mg/l (mean 60 mg/l), measured in a total of 471 subjects (adults and children). DISCUSSION AND CONCLUSIONS: The PbB levels currently found in children resident in Lucca confirm a low-risk environmental situation. Preventive measures specifically aimed at children do not therefore appear to be justified at present.

Adolescent↗
PubMed1995

[Long-term prognosis after coronary angioplasty in relation to the presence of modifiable factors of coronary risk].

Short-term outcome after coronary angioplasty is mainly determined by restenosis, while long-term outcome is determined by new events due to incomplete revascularization, by atherosclerosis progression and by late-restenosis. The aim of this study is to assess if correctly treated coronary risk factors are predictors of poor prognosis after coronary angioplasty. Two-hundred and twenty six patients (209 males, 17 females, mean age 56 +/- 9 years) with successful coronary angioplasty were treated for coronary risk factors. New events (death, myocardial infarction, repeat angioplasty, bypass surgery) were recorded. Ischemia was evaluated by serial exercise tests. The mean follow-up was 31 +/- 12 months. Survival was 99.5% at 1 year and 97.4% after 5 years; "event free survival" was 84.6% at 1 year and 65.9% after 5 years; "ischemia free survival" was 84.6% at 1 year and 44.8% after 5 years. "Ischemia free survival" was higher in patients with single coronary angioplasty and in patients with infarct-related vessel angioplasty. Smoke addiction, diabetes, hypercholesterolemia and hypertension were not significantly correlated with "ischemia free survival". Smokers and diabetics had a trend towards a less favorable 5 year outcome, but without statistical differences. In conclusion, this study shows that correctly treated coronary risk factors do not worsen prognosis after coronary angioplasty.

Aged↗
PubMed1995

Synthesis of some 4H-pyrido[1,2-a]pyrimidin-4-ones investigated as antimicrobial agents.

Synthesis of some 4H-pyrido[1,2-a]pyrimidin-4-ones and assay of their antibacterial and antifungal activity are reported. Compounds 3a-e,g were prepared by reaction of substituted 2-chloromethyl-4H-pyrido[1,2-a]pyrimidin-4-ones 2a-c with suitable amines. These compounds and the previously obtained analogues 5a-o and 6a,b have been tested for their antimicrobial activity. All tested compounds were devoid of antimicrobial activity.

Anti-Bacterial Agents↗
PubMed1995

Lactate catabolism by enzyme-loaded red blood cells.

Two different enzymes that metabolize lactate in the presence of oxygen, either to acetate plus CO2 (lactate 2-mono-oxygenase; Lmox) or to pyruvate plus H2O2 (lactate oxidase; Lox) were encapsulated in human and murine red blood cells (RBCs). Lmox shows a low affinity for lactate (Km 22 mM) and thus works at a low rate at the lactate concentrations found in hyperlactataemia (5-20 mM). Encapsulation of Lox provides a constant catabolic rate under the same range of blood lactate concentrations, but generates H2O2, which is toxic to the enzyme-loaded RBCs. Co-encapsulation of both enzymes at a ratio of 20 units of Lmox/unit of Lox results in significant rates of lactate metabolism over a wide range (1-30 mM) of lactate concentrations with modest methaemoglobin formation (5-8.5%) and normal cellular ATP concentrations (1.1-1.23 mM). In vitro experiments with [1-14C]glucose and [U-14C]glucose have shown that Lmox/Lox-loaded RBCs counteract the production of H2O2 by increasing the amount of glucose metabolized in the pentose phosphate pathway. In vivo attempts to prove the efficacy of these engineered RBCs in removal of blood lactate in mice have failed because of the high aerobic capacity and high lactate metabolism of these animals. However, the results obtained in vitro suggest that the encapsulation of lactate-catabolizing enzymes may be useful in the treatment of hyperlactataemia.

Acetates↗
PubMed1995

Morphometric and densitometric approach in hypertrophic cardiomyopathy (HCM).

The aim of this study was to apply an easy method for the quantitative evaluation of changes in myocardial fibrocell size (area, diameter, circular shape factor, nuclear area, DNA content), and in the fibrous-interstitial area in hypertrophic cardiomyopathy (HCM) by mean of a computerized image analysis. A Vidas image analyser was employed for the morphometric study. The following parameters were assessed: area, maximum and minimum diameters, circular shape factor of myocytes; percentage of fibrosis; DNA content (integrated optical density) nuclear area of myocytes. The morphometric results in HCM compared to the ones in normal hearts, indicate an increase in the myocyte area and the transverse diameters, especially in the septum and left ventricle, altogether illustrating the hypertrophic condition of the myocytes, and increased fibrotic area was found in the left ventricular wall and septum (22.6 +/- 2.1% and 15.9 +/- 2.9% respectively). Densitometric analysis showed a significant increase in all test samples then compared with controls. The increase in the two nuclear parameters (area and DNA) also suggests hyperplasia. It is concluded that the morphometric determination of the morphologic abnormalities occurring in HCM by a rapid and less laborious approach, is an extremely useful method to describe the characteristics of this pathologic condition.

Adult↗
PubMed1995

Immunocytochemical study of binding and internalization of carrier-free Cu, Zn Superoxide dismutase by cultured rat hepatocytes.

Internalization of superoxide dismutase-gold complex by isolated liver cells has been shown to occur via receptor-mediated endocytosis. As colloidal gold may act as a carrier in this process, carrier-free human Cu, Zn superoxide dismutase was incubated with cultured rat hepatocytes. Light and electron microscopy immunocytochemistry revealed the binding and internalization of free native human Cu, Zn superoxide dismutase (hSOD) by cultured rat hepatocytes. Immunocytochemical demonstration of binding to the cell surface (hepatocytes were incubated with hSOD for 15 min. at 4 degrees C) and internalization (hepatocytes were incubated with hSOD for 15, 30 and 60 min. at 37 degrees C) of the carrier-free superoxide dismutase was achieved by using a monoclonal antibody selectively reacting with the human protein. The results obtained indicate that carrier-free superoxide dismutase is bound and internalized by rat hepatocytes in primary cultures and that the enzyme can enter the cells via a receptor-mediated endocytosis pathway. We followed the binding and the internalization process of hSOD thus validating the use of the native enzyme in the therapy of free radical-related diseases.

Animals↗
PubMed1995

The epizootiology of sarcoptic mange in chamois, Rupicapra rupicapra, from the Italian eastern Alps.

Sarcoptic mange is the most severe infection in chamois in the Eastern Alps. This study analyses and discusses data from two mange foci in the Foresta Demaniale di Tarvisio (NE Italy). The first impact of mange on naive host populations was dramatic, with mortality rates of over 80%. The chamois herds were decimated, but they recovered quite fast and two later epizootics were observed to have a far less severe impact on the chamois population. Intervals between successive waves lasted 10 to 15 years. No sign of low reproductive performance nor evidence of a poor physical condition of the animals was observed in the years preceding the new epizootic waves. Mortality rates were only slightly influenced by the density of the host population. In a long lasting focus of disease, adult males appeared more vulnerable to mange than other sex and age classes. Cases of mange were also more frequent in winter and spring. This seasonal trend may be explained by the interaction between the dynamics of mites, ethological patterns-rut activity-and the poorer physical condition of the host during this period.

Age Distribution↗
PubMed1994

Differential decrease of copper content and of copper binding to superoxide dismutase in liver, heart and brain of copper-deficient rats.

Dietary copper-deficiency in rats produced a organ-specific decrease of copper content. This was paralleled by a decrease of the activity of the copper-enzyme superoxide dismutase. In liver such a decrease is partially due to the existence of an apo-form of superoxide dismutase, which can be reactivated by addition of exogenous copper to tissue extracts. These results demonstrate in vivo that superoxide dismutase is post-translationally modulated by copper in higher vertebrates as previously found for yeast and mammalian cells in culture.

Animals↗
PubMed1994

Prognostic value of left ventricular mass in uncomplicated acute myocardial infarction and one-vessel coronary artery disease.

This study assesses the relative prognostic value of increased left ventricular (LV) mass compared with residual ischemic myocardium and angiographic characteristics of the diseased vessel in 76 patients with uncomplicated acute myocardial infarction associated with 1-vessel coronary artery disease (CAD). All patients underwent symptom-limited treadmill exercise testing, resting and dipyridamole echocardiography and coronary angiography before discharge, and were followed-up for 32 +/- 6 months. LV measurements were obtained in diastole according to the Penn convention. Measurements of LV mass were divided by body surface area to obtain LV mass index. A cut-off value of 135 g/m2 body surface area for men and 112 g/m2 for women was prospectively selected. The individual effects of clinical, stress testing and angiographic variables were evaluated by using the Cox regression model. Echocardiographic LV mass index was increased in 43 patients and normal in 33. There was no intergroup difference with respect to baseline clinical and angiographic variables, ejection fraction and prevalence of stress-induced ischemia. During follow-up there were 23 cardiac events in the 43 patients with increased LV mass index and only 5 in the 33 with normal LV mass index (p < 0.001). No patient died or had nonfatal reinfarction among patients with normal LV mass. Cox survival analysis identified an increased LV mass index as the only independent predictor of cardiac events (chi-square = 7.9; p < 0.005; RR = 5.4). Thus, these data suggest that LV mass is an important independent risk factor in patients with uncomplicated acute myocardial infarction associated with 1-vessel CAD.

Adult↗
PubMed1994

Red blood cell phagocytosis following hexokinase inactivation.

Hexokinase inactivating antibodies were loaded into human erythrocytes using an encapsulation procedure based on hypotonic haemolysis, isotonic resealing and reannealing. Red blood cells loaded with anti-hexokinase IgG showed 20 percent residual hexokinase activity and reduced glycolytic activity. Incubation of these cells in the presence of an oxidizing agent such as terbutyl hydroperoxide (TBH) and then in autologous plasma, promoted opsonization by autologous IgG and complement deposition, but not haemolysis. Furthermore, the antihexokinase IgG loaded cells treated with TBH were actively recognized and phagocytosed by macrophages. Thus, metabolic impairment of human erythrocytes promotes autologous IgG binding, C3 deposition and phagocytosis, a mechanism already reported for the removal of senescent erythrocytes.

Complement System Proteins↗
PubMed1994

Effect of intravenous human gastrin-releasing peptide on food intake in humans.

BACKGROUND/AIMS: Bombesin and gastrin-releasing peptide (GRP) are closely related peptides. Both have been proposed to serve as a satiety signal in animals. METHODS: To explore further the role of GRP in humans, its effects on satiety and eating behavior were investigated by infusion of GRP into healthy men at three dosages (10, 40, and 160 pmol/kg per hour) and compared with saline infusions. RESULTS: GRP produced a significant reduction in calorie intake (P < 0.05) but only a 19% (nonsignificant) reduction in food intake. Fluid ingestion was not affected by GRP. No overt side effects were produced by GRP, but subjects experienced d less hunger and early fullness in the premeal period during GRP infusion but not when receiving saline (P < 0.05-0.01). CONCLUSIONS: This study shows that intravenous infusions of GRP can decrease spontaneous food intake at concentrations that produce physiological effects, such as stimulation of acid or pancreatic secretion or gallbladder contraction. The data imply that GRP-like peptides can act as satiety signals in humans, confirming data previously reported in animals.

Adult↗
PubMed1994

Oral nodular fasciitis. A case report.

A rare case of nodular fasciitis arising in the buccinator muscle sheath in a 76-year-old patient is reported. Nodular fasciitis is a benign proliferation of fibroblasts, often mistaken for a sarcoma because of its rapid growth, rich cellularity and high mitotic activity. Although the cause of nodular fasciitis is unknown, it is likely that the fibroblastic proliferation is due to local injury or an inflammatory process.

Aged↗