Biomedical subjects

L Santoro

Publications and source records attributed to L Santoro.

At least 109 records · Page 6Linked to original sources

PubMed1994

Serum cholesterol and acute myocardial infarction: a case-control study from the GISSI-2 trial. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto-Epidemiologia dei Fattori di Rischio dell'Infarto Miocardico Investigators.

OBJECTIVE: To examine the role of serum cholesterol in acute myocardial infarction in a population of patients with no history of coronary heart disease and to establish the nature of this association, the degree of risk, and the possible interaction between serum cholesterol and other major risk factors for acute myocardial infarction. DESIGN: Case-control study. SETTING: 90 hospitals in northern, central, and southern Italy. PATIENTS: 916 consecutive cases of newly diagnosed acute myocardial infarction and 1106 hospital controls admitted to hospital with acute conditions not related to known or suspected risk factors for coronary heart disease. DATA COLLECTION: Data were collected with a structured questionnaire and blood samples were taken by venepuncture as soon as possible after admission to hospital from cases and controls. Blood cholesterol concentrations were available for 614 cases and 792 controls. RESULTS: After adjustment by logistic regression for sex, age, education, geographical area, smoking status, body mass index, history of diabetes and hypertension, and family history of coronary heart disease the estimated relative risks of acute myocardial infarction for quintiles of serum cholesterol (from lowest to highest) were 2.3 (95% confidence interval (CI) 1.6 to 3.4), 3.1 (95% CI 2.1 to 4.6), 4.1 (95% CI 2.8 to 6.0), and 5.2 (95% CI 3.5 to 7.7). The estimated relative risk across selected covariates increased from the lowest to the highest quintile of serum cholesterol particularly for men, patients under 55 years of age, and smokers. When the possible interaction of known risk factors with serum cholesterol was examined, smoking habits, diabetes, and hypertension had approximately multiplicative effects on relative risk. CONCLUSIONS: This study indicates that serum cholesterol was an independent risk factor for acute myocardial infarction. This association was linear, with no threshold level. Moreover, there was a multiplicative effect between cholesterol and other major risk factors on the relative risk of acute myocardial infarction.

Adult↗

PubMed1993

Tar yield of cigarettes and risk of acute myocardial infarction. GISSI-EFRIM Investigators.

OBJECTIVE: To analyse the relation between tar and nicotine yield of cigarettes smoked in the recent past and the risk of myocardial infarction. DESIGN: Multicentre case-control study conducted between September 1988 and June 1989. SETTING: Over 80 coronary care units in various Italian regions. SUBJECTS: 916 patients with acute myocardial infarction without history of ischaemic heart disease and 1106 controls admitted to hospital for acute conditions not related to known or suspected risk factors for ischaemic heart disease. MAIN OUTCOME MEASURES: Relative risk of myocardial infarction according to type of cigarette smoked adjusted for identified potential confounding factors. Brands of cigarettes classified according to yield of tar and nicotine. RESULTS: Patients with acute myocardial infarction were more often smokers and among smokers they tended to smoke more cigarettes. Compared with non-smokers their estimated relative risks were 3.8, 4.3, 3.2, and 3.7 in the four categories of tar yield (< 10, 10-15, > 15-20, and > 20 mg, respectively). No trend in risk across yields was evident when analysis was restricted to smokers and allowance was made for number of cigarettes. Compared with risks in subjects in the lowest category of tar yield the relative risks were 1.2, 0.8, and 1.0 for the subsequent yields. Compared with risks in non-smokers the relative risks ranged from 9.3 to 12.6 below the age of 50 but no trend was observed with increasing yield. CONCLUSIONS: Changing to cigarettes with a lower tar yield is not an effective means of reducing tobacco related morbidity from myocardial infarction.

Adult↗

PubMed1993

Coffee consumption and serum cholesterol. GISSI-EFRIM Study Group.

The relationship between coffee consumption and serum cholesterol was examined in the comparison group of a case-control study of myocardial infarction involving 642 patients from various Italian regions who were hospitalized for diseases having no relationship to cardiovascular disease risk factors. Overall mean total cholesterol was 198.9 mg/dl. Mean cholesterol values (in mg/dl) standardized for age, sex, and smoking habits were 204.0 for nonconsumers of coffee, 194.8 for drinkers of one cup per day, 196.5 for two, 202.9 for three, 205.9 for four, and 206.5 for five or more cups per day. Thus, serum cholesterol levels were higher in non-coffee drinkers than in moderate drinkers; among coffee drinkers, however, there was a direct, although moderate, relationship between the amount of coffee consumed and the total cholesterol levels. A similar though less consistent pattern was also evident across separate strata of sex, age, and smoking habits, and the association was appreciably greater among younger subjects (below age 50). Although mean cholesterol levels in this Italian dataset were lower than those in other populations from northern Europe and the United States, the relative difference between moderate and heavy drinkers was proportionally similar to that reported in other studies. These results are of special interest since most Italian coffee (i.e., mocha or espresso) is unfiltered.

Adult↗

PubMed1993

Major involvement of cathepsin B in the intracellular proteolytic processing of exogenous IgGs in U937 cells.

Monoclonal antibodies used for diagnostic and therapeutic purposes behave as antigens when injected into patients. They are recognized by T cells in a processed form and in a major histocompatibility complex class II restricted fashion. Monoclonal murine IgG2a were used as a model to analyse the early phase of antigen processing in U937 cells. IgG2a prebound to cell surface Fc receptors were rapidly internalized in the cells. During internalization, they were proteolysed with a time-dependent intracellular accumulation of 26, 25, 24, 22 and 14 kDa fragments. Comparison of in vitro IgG2a proteolysis by U937 subcellular fractions or by purified cathepsin B and their intracellular processing indicated that a major cathepsin B like protease is responsible for IgG2a intracellular processing in endo-lysosomal compartments of U937 cells.

Cathepsin B↗

PubMed1993

Influence of diabetes on mortality in acute myocardial infarction: data from the GISSI-2 study.

OBJECTIVES: This study was conducted to determine the role of insulin-dependent and noninsulin-dependent diabetes in the prognosis of patients after myocardial infarction and treatment with fibrinolytic agents. BACKGROUND: Several studies have shown that diabetic patients have a high mortality rate after acute myocardial infarction. However, the impact of diabetes on survival in patients treated with fibrinolytic agents is still undefined. It is also not known whether the type of diabetes or gender affects prognosis. METHODS: We analyzed prevalence and prognostic significance of a history of diabetes in patients enrolled in the GISSI-2 study, all of whom received fibrinolytic agents. The incidence of deaths in the hospital and at 6 months after study entry was computed for patients without diabetes and for insulin-dependent and noninsulin-dependent diabetic patients; relative risks were evaluated by univariate and multivariate analysis. RESULTS: Information on diabetic status was available for 11,667 patients, 94.2% of those randomized in the GISSI-2 study. The prevalence of diabetes was higher in women than in men (8.75% vs. 1.85%, p < 0.01 for insulin-dependent and 23.7% vs. 13.8%, p < 0.01 for noninsulin-dependent diabetic patients). The type of fibrinolytic agent did not affect mortality rates; the increase in in-hospital mortality of diabetic patients was moderate and similar for men with insulin- and noninsulin-dependent diabetes (8.7% and 10.1%, respectively, vs. 5.8% in nondiabetic patients); in women, mortality was markedly higher for insulin-dependent and only slightly higher for noninsulin-dependent diabetic patients (24.0% and 15.8%, respectively, vs. 13.9% for nondiabetic patients). The adjusted relative risks were 1.9 (95% confidence interval 1.2 to 2.9) for insulin-dependent diabetic women and 1.4 (95% confidence interval 1.1 to 1.8) for noninsulin-dependent diabetic men. The mortality rate after discharge showed a similar gender difference, and in insulin-dependent diabetic women, prognosis was ominous even in the absence of left ventricular damage before discharge. CONCLUSIONS: A history of diabetes is associated with a worse prognosis after myocardial infarction, even in patients treated with fibrinolytic agents. Gender and type of diabetes appear to be critical in affecting survival. In men, both insulin-dependent and noninsulin-dependent diabetes are associated with a moderately higher mortality rate; in women, insulin-dependent diabetes is, in itself, a strong risk factor for death after myocardial infarction.

Aged↗

PubMed1993

Coffee consumption and risk of acute myocardial infarction in Italian males. GISSI-EFRIM. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto, Epidemiologia dei Fattori di Rischio del'Infarto Miocardico.

The relationship between coffee consumption and acute myocardial infarction (AMI) was analyzed using data from a case-control study conducted in 1988 to 1989 within the framework of the GISSI-2 trial on streptokinase versus alteplase and heparin versus no heparin in the treatment of AMI. A total of 801 male patients with AMI and 792 control subjects who were hospitalized in several Italian regions for diseases unrelated to known or potential risk factors for cardiovascular diseases were included. Compared with coffee nondrinkers, the multivariate relative risks (RRs), after allowance for age, education, body mass index, smoking habits, alcohol consumption, family history of AMI, cholesterol level, history of diabetes, and hypertension, were 0.8 (95% confidence interval (CI), 0.5 to 1.2) for consumption of one cup/d, 1.3 (95% CI, 0.9 to 2.0) for two cups/d, 1.8 (95% CI, 1.1 to 2.7) for three cups, 2.5 (95% CI, 1.5 to 4.1) for four cups, and 2.6 (95% CI, 1.6 to 4.2) for five cups or more. The trend in risk with dose was statistically significant (P < 0.001). Duration of coffee consumption was not associated with the risk of AMI. The RRs for daily coffee consumption were elevated across strata of various covariates, including age, smoking habits, cholesterol level, diabetes, and hypertension, with a particularly elevated (although not significantly heterogeneous) estimate in patients younger than 50 years (RR, 5.7; 95% CI, 3.0 to 10.9 for four or more cups/d). The RR in patients who drank four or more cups of coffee per day and were current smokers was 8.1 (95% CI, 5.1 to 13.0), suggesting an unfavorable effect on the combination of cigarette smoking and high coffee intake on the risk of AMI.

Adult↗

PubMed1993

Physical activity and the risk of acute myocardial infarction. GISSI-EFRIM Investigators. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto-Epidemiologia dei Fattori di Rischio dell'Infarto Miocardico.

The relationship between physical activity and acute myocardial infarction (AMI) was examined in a case-control study conducted in Italy in 1988 to 1989 within the framework of the GISSI-2 trial of streptokinase versus alteplase and heparin versus no heparin in the treatment of AMI. A total of 916 case patients admitted to coronary care units from various Italian regions for AMI were interviewed. Control subjects were 1106 patients admitted to the same network of hospitals for a broad spectrum of acute diseases not related to known or potential risk factors for myocardial infarction. Among various types of physical activity (occupational activity, walking, stair climbing, and sport and leisure-time physical activity), occupational physical exercise emerged as the most protective. Multivariate odds ratios (ORs) were 1.4 (95% confidence interval (CI), 1.0 to 2.0) and 1.6 (95% CI, 1.2 to 2.1) for the two lowest levels of occupational physical activity. The trends of increasing risk with decreasing activity were consistent, although less strong, when other types of activity were considered. The protection conveyed by occupational physical activity was similar across various strata of sex, age, education, smoking habits, and diabetes, and was not explained by serum cholesterol, body weight, or hypertension. This study therefore confirms that low physical activity is an indicator of subsequent risk of AMI.

Adult↗

PubMed1993

[Cutaneous microcirculation in systemic sclerosis. Morpho-functional research using capillaroscopy and laser-Doppler].

Our previous researches proved that, in patients affected by Raynaud disease, microcirculatory alterations were greater in those cases in which the small vessels showed evocative appearances of a sclerodermatous connectivopathy. In this study we evaluated cutaneous microvasculature in 18 patients suffering from clear systemic sclerosis, compared with a group of 16 subjects affected by primitive Raynaud disease and a group of healthy subjects. We used videocapillaroscopy and laser-Doppler fluxmetry for morphological and functional study respectively. In patients affected by systemic sclerosis the rest flow was clearly reduced and morphological pattern of cutaneous small vessels deranged. The response to ischemic test allowed us to subdivide the skin-bounds in two subgroups: "no responders" 8 subjects (44%), in which reactive hyperaemia was completely absent, "responders" 10 patients (56%) in which the hyperaemia was completely overlapped with that of the two other groups, but with longer reaction times. In skinbounds the capillaroscopic pattern was clearly severe in comparison with other two groups (18.8 +/- 5.7 vs 5.7 +/- 2.3 and 3.6 +/- 1). Thus, in advanced stage of the pathology, is microangiopathy (in its tromboischemic and inflammatory aspects) that plays a very important role in the development of organ damage. Therefore, all those clinical and instrumental tests which may allow a differential early diagnosis between a primitive and a secondary Raynaud phenomenon be done, for its prognostic value in connection with the appearance of systemic sclerosis.

Adult↗

PubMed1993

Effects of sympathetic stimulation on microcirculatory dynamics in patients with essential acrocyanosis. A study using mental stress.

With the aim of examining possible alterations of the neurogenic regulation of microvascular hemodynamics, the cutaneous microcirculation in 21 patients with essential acrocyanosis was studied using a laser-Doppler method both in basal conditions and during mental stress using an arithmetic test. The analysis of results showed a significant reduction in basal flow (p < 0.02) in patients with acrocyanosis in comparison to control subjects. In 15 out the 21 patients studied it was found that there was an increase in the flowmetric curve during mental stress, whereas the test caused a diminished flow in normal subjects. The altered response to sympathetic stimulus might be the result of microcirculatory stasis which would provoke an alteration in the neurogenic regulation mechanisms of microvascular dynamics.

Adolescent↗

PubMed1992

Amiodarone-induced experimental acute neuropathy in rats.

Amiodarone was injected endoneurially at increasing doses into the exposed tibial nerve of rats to study its electrophysiologic and pathologic effects on peripheral nerve fibers. Forty-five male Wistar rats were used, and each of the following concentrations was injected into 15 nerves: 25 micrograms/mL, 50 micrograms/mL, and 100 micrograms/mL. Microinjection of a 25 micrograms/mL concentration of amiodarone resulted in a subacute, incomplete conduction block evident at day 3 postinjection. This conduction block remained stable until day 10 and recovery was complete at day 35. Microinjection of a 50 micrograms/mL concentration of amiodarone produced a faster evolving conduction block, and significant axon degeneration (approximately 40% of fibers). Injection of a 100 micrograms/mL concentration resulted in severe acute motor axon degeneration followed by complete but delayed regeneration. Results of morphological studies closely correlated with electrophysiological findings. Amiodarone thus seems to have a direct toxic effect on axons at high concentrations in the peripheral nerve, and we suggest that different pathological changes described in human amiodarone neuropathy could be related to different concentrations of the drug in the nerve, perhaps due to variability of blood-nerve barrier efficacy.

Amiodarone↗

PubMed1992

Is early onset cerebellar ataxia with retained tendon reflexes identifiable by electrophysiologic and histologic profile? A comparison with Friedreich's ataxia.

An electrophysiologic and histologic study was performed on 18 patients affected by early onset cerebellar ataxia with retained tendon reflexes (EOCA). Sensory and motor conduction velocity (SCV, MCV) was measured along peripheral nerves in all patients, somatosensory (SSEP) and brainstem auditory evoked potentials (BAEP) were recorded in 13; cortical stimulation (CS) in 12, and sural nerve biopsy in 4 patients were also performed. The results as a whole allow a division of EOCA patients into 2 groups: with (7 patients) and without (11 patients) peripheral neuropathy. Among EOCA patients with neuropathy a differential diagnosis with Friedreich's disease patients was not possible according to BAEPs and CS, while SSEPs could differentiate 2 out 5 patients in whom they were performed.

Adolescent↗

PubMed1992

Body mass and acute myocardial infarction. GISSI-EFRIM Investigators.

BACKGROUND: The relation between body mass index and acute myocardial infarction was analyzed using data from a multicentric case-control study conducted in Italy between September 1988 and June 1989 within the framework of the GISSI-2 trial. METHODS: Subjects were 916 patients with acute myocardial infarction and no history of cardiovascular disease and 1,106 controls hospitalized for acute conditions not related to known or suspected risk factors for ischaemic heart disease. RESULTS: Relative to the lowest quintile of the Quetelet Index (weight/height2) the estimated risks for subsequent quintiles were 1.2 (95% confidence intervals, (CI): 0.9 to 1.6), 1.7 (95% CI: 1.2 to 2.2), 1.8 (95% CI: 1.4 to 2.4), and 2.2 (95% CI: 1.7 to 3.0) when adjustment was made for age, sex, education, and smoking habits by means of logistic regression. The association was consistent across strata of sex, education, and smoking status, but not age. The estimated risk for subjects in the fifth quintile of the Quetelet Index relative to those in the first was 4.1 under 55 years of age, but only 1.7 between 55 and 64 years and 1.5 above age 65. CONCLUSION: The relation between body mass and myocardial infarction was explained, at least in part, by higher serum cholesterol levels and the prevalence of diabetes and hypertension among fatter subjects. This does not, however, totally eclipse a possible causal relation between body mass and risk of myocardial infarction, since these conditions are a consequence, rather than a confounder, of overweight.

Adult↗

PubMed1992

Upper gastrointestinal tract motility in children with progressive muscular dystrophy.

Gastric emptying was evaluated in 15 children (mean age, 8.0 years) with progressive muscular dystrophy to detect early gastrointestinal smooth muscle involvement; 10 of the children also underwent esophageal manometry. Clinical evidence of skeletal muscle dysfunction was minimal in 14 of the 15 patients; 10 of them had no gastrointestinal symptoms. Gastric emptying studies were performed by using 500 muCi of technetium 99m-sulfur colloid bound to a scrambled egg, and scintigraphic measurements were made continuously for 60 to 90 minutes. Gastric emptying studies and manometric tracings were compared with those from 11 children (mean age, 8.4 years) without gastrointestinal or muscular disorders. Mean (+/- SD) percentage retention of gastric isotope was significantly greater in patients with muscular dystrophy than in control subjects. No differences were found between the two groups in distal esophageal motility or in upper and lower esophageal sphincter pressures or relaxation. Contraction amplitudes in the upper portion of the esophagus, however, were significantly lower in patients with myopathy than in control subjects. These data suggest that dysfunction of smooth muscle of the upper gastrointestinal tract is detectable in children with muscular dystrophy early in the course of the disease, even when gastrointestinal symptoms are absent and skeletal muscle symptoms are minimal.

Adolescent↗

PubMed1992

Modulation of arterial smooth muscle cell growth by haemodynamic forces.

To define the correlation between flow dynamics and the proliferation of arterial smooth muscle cells (SMCs), bovine arterial SMC were subjected to increasing laminar flow shear stress in an in vitro system. Smooth muscle cells were seeded in a fibronectin-coated polystyrene cylinder at 5 x 10(5) cells/tube. The experimental groups were subjected to increasing shear stress (3, 6, 9 dyn cm-2) for a 24-h period. The control group was subjected to similar incubation conditions without flow. Shear stress reduced significantly (p less than 0.01) the 24-h incorporation of tritiated thymidine and cell proliferation. This effect was proportional to the level of shear stress and was still evident 24 h after flow cessation. Flow cytometry demonstrated a lower percentage of SMCs in S-phase with increasing shear stress. Extrapolation of these findings to the clinical setting might explain how unphysiological shear stress can predispose to the abnormal proliferation rate of SMCs and early plaque formation.

Animals↗

PubMed1992

The relationship between electrophysiological findings, upper limb growth and histological features of median and ulnar nerves in man.

In 19 median and 10 ulnar nerves of 28 healthy young volunteers, the maximum orthodromic sensory conduction velocity was studied along one or two fingers (the third and/or the fifth), the palm, and the forearm. In five 20 to 32-yr-old males and in a newborn male, post-mortem samples of either the median or the ulnar nerve were obtained from the finger (either the third or the fifth), the palm, the wrist and the forearm in order to study the size distribution of external fibre and axon diameters, and the fibre internodal length. In 2374 infants, children and adolescents, the height, length of both the third and the fifth finger, length of the palm, and length of the forearm were measured. The results showed (i) a significantly slower conduction velocity along the fingers; (ii) a significantly shorter internodal length without remarkable fibre diameter changes in the same nerve segments; (iii) a significantly smaller elongation of these body parts; (iv) a significant correlation between these data. In conclusion, internodal length seems to play an important role in governing conduction velocity of myelinated peripheral nerve fibres.

Adolescent↗

PubMed1992

Role of family history in patients with myocardial infarction. An Italian case-control study. GISSI-EFRIM Investigators.

BACKGROUND: A family history of heart disease has been reported to increase the risk of coronary heart disease. We examined the relation between family history of myocardial infarction (MI) and risk of acute MI to establish the independency of this association, the degree of risk in relation to the number and age of relatives affected, and the possible interaction between family history and other major risk factors for MI. METHODS AND RESULTS: In a case-control study conducted in Italy within the framework of the GISSI-2 Trial, 916 cases of newly diagnosed MI and 1,106 hospital controls were identified. Using a structured questionnaire, data were collected on the history of MI in first-degree relatives and the age at which the event occurred. Compared with subjects without family history of MI in first-degree relatives, the relative risk (RR) of MI was 2.0 (95% confidence interval, CI, 1.6-2.5) in those with one and 3.0 (95% CI, 2.0-4.4) in those with two or more relatives affected (chi 2(1) test for trend, 54.1; p less than 0.001). Such an increase was not substantially affected by allowance for recognized risk factors. The risk related to family history involving at least two relatives was higher for early MI (less than 55 years) (RR, 20.0; 95% CI, 3.3-121.2) compared with later MI (less than or equal to 65 years) (RR, 3.5; 95% CI, 1.8-6.6). When known risk factors were considered for their interaction with family history, the effect on RR was approximately multiplicative for several variables, including smoking, serum cholesterol, hypertension, and hyperlipidemia but not for diabetes and body mass index. Thus, the presence of both family history and smoking and cholesterol levels greater than or equal to 226 mg/dl led to an RR of 14 (95% CI, 3.7-50.0) and 8.3 (95% CI, 1.8-38.7), respectively. CONCLUSIONS: This study indicates that a family history of MI is an independent risk factor for MI, and that the number of relatives and the age at which they were affected is related to the strength of the association. There is a multiplicative effect on RR between family history and several major risk factors for MI.

Case-Control Studies↗

PubMed1992

Nerve conduction and electromyography.

The advent of computer-based methodology in routine electromyography has much improved the analysis of motor unit (MU) decomposition, of interference pattern study, and of MU counting. Measuring minimum motor and sensory conduction velocities is becoming more accessible and is considered an essential procedure in assessing the condition of peripheral nerves. A series of studies has shown that nerve resistance and vulnerability can be modified by a steep temperature gradient, by ciguatera toxin, or by hyperventilation-induced changes in the electrical properties of the axonal membrane. The controversy as to the diagnostic procedures to use in cases of radiculopathy and carpal tunnel syndrome (CTS) shows no sign of abating. There is, however, general consensus that electrophysiologic procedures must play a key diagnostic role in these conditions. Lastly, several interesting articles have been published describing the use of electrophysiologic tests in motor neurone diseases. Moreover, some advances have been made in the diagnostic yield of single-fibre electromyography (SFEMG) with axonal microstimulation in myasthenia gravis and Eaton-Lambert myasthenic syndrome.

Animals↗

PubMed1992

Analysis for transaminases in serum with an amperometric glutamate electrode.

We determined transaminases in human blood serum with an amperometric glutamate biosensor. The probe was a hydrogen peroxide sensor assembled with appropriate selective membranes to enhance the probe specificity and lifetime. Calibration curves of glutamate were linear in the range 1-1000 mumol/L, with a response time of < 1 min. This probe was subsequently applied to the measurement of activities of aspartate and alanine aminotransferases in human sera. Analytical recovery studies demonstrated the suitability of the glutamate sensor by measuring 91-99% of added glutamate, 92-106% of added aspartate aminotransferase, and 101-105% of added alanine aminotransferase. Transaminase activity measured in 80 sera correlated well with results obtained with a spectrophotometric procedure.

Alanine Transaminase↗