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F Marcon

Publications and source records attributed to F Marcon.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Anomalous origin of the left main coronary artery from the right coronary sinus and trajectory to the great vessels. Value of echocardiography in a child].

During a routine medical check-up, a pathological electrocardiogram was recorded in an asymptomatic 6 year old girl. The demonstration of coronary insufficiency by exercise stress testing and sestamib myocardio-scintigraphy led to the diagnosis of an anomalous origin of the left coronary artery. This vessel arose from the right coronary sinus and continued anteriorly to the main coronary artery. The data of the literature suggest that the risk of sudden death and of coronary insufficiency is associated with the passage of the left coronary artery between the aorta and pulmonary artery. The authors describe the anomalous origin of the left coronary artery and its trajectory with respect to the great vessels by echocardiography, using a high frequency transducer. The anterior direction of the left coronary artery in front of the main pulmonary artery may lead to ischaemia on effort even without stenosis at coronary angiography. Echocardiography may therefore be useful in children with positive exercise stress tests for diagnosing anomalous coronary vessels and their relationship with respect to the great vessels.

Child↗
PubMed1995

Genetic effects of petroleum fuels: cytogenetic monitoring of gasoline station attendants.

Workers in the petroleum distribution trades experience relatively high-level exposures to fuel vapours whose consequences have not been fully elucidated. In this study, the possible relationship between occupational exposure to petroleum fuels and cytogenetic damages in peripheral lymphocytes was investigated. Twenty-three male, non-smoking workers from the area of Rome were enrolled in the study, together with age-paired controls with no occupational exposure to fuels. Peripheral lymphocyte cultures were set up for the analysis of structural chromosome aberrations (CAs), sister chromatid exchanges (SCEs) and micronuclei (MN) in cytokinesis-blocked lymphocytes. Frequencies of CAs, SCEs and MN were compared between exposed and control groups, and evaluated in relation to blood lead level (as an indicator of engine exhausts exposure) for the whole group under study, and to yearly averaged exposure to benzene (8-h time weighted averages, as determined by repeated personal sampling) for fillingstation attendants only. Both CAs and SCEs were slightly increased in station attendants: 1.97 versus 1.46 aberrations per 100 cells, and 4.73 +/- 0.15 versus 4.48 +/- 0.11 SCEs/cell in exposed and control individuals, respectively. The difference between cumulative CA rates in the exposed and control populations was of borderline statistical significance (p = 0.066). However, when the exposed population was dichotomized for benzene exposure, a significant (p = 0.018) correlation of CAs with benzene exposure was found. The analysis of SCE data highlighted a significant increase of cells with more than 6 exchanges (HFCs), corresponding to the 75 degrees percentile of the overall distribution, in fillingstation attendants (relative risk (RR) = 1.3, 95% CI = 1.1-1.5) in comparison with controls. In the pooled population, the frequency of HFCs showed a statistically significant upward trend at increasing blood lead levels (chi 2 for trend = 27.8, p < 0.0001). A complex relationship between SCEs and benzene exposure was observed, with an increased frequency of HFCs in the medium exposure intensity class (RR = 1.5, 95% CI = 1.2-1.7), and no difference for exposure to higher benzene levels (RR = 1.0, 95% CI = 0.9-1.2), compared to reference subjects. Finally, the analysis of MN in both phytohemagglutinin- and pokeweed-stimulated cell cultures did not show significant excess of MN in binucleated lymphocytes of exposed workers with respect to the age-paired controls.

Adult↗
PubMed1995

[Exposure to benzene and genotoxic effects among filling station attendants].

Exposure to gasoline vapors is classified by the International Agency for Research on Cancer as possibly carcinogenic to humans, mainly on the basis of the established carcinogenicity of some component chemicals such as benzene. The mechanism of benzene toxicity, particularly its leukemogenic effects, is far from being fully understood. Different studies, aimed at evaluating the risk associated with exposure to benzene through fuels and coordinated by the Istituto Superiore di Sanità, are in progress in Italy. In an environmental monitoring survey on a sample of 111 service stations, conducted in Rome (Italy) in 1992, average yearly personal exposure to benzene, toluene and xylenes were estimated. Chemical determination of benzene and methylbenzene was carried out by GL-gas chromatography. From a sample of 27 service stations 34 fuel samples were collected, and their benzene content was measured by hr-gas chromatography. Subgroups of the filling station attendants undergoing the exposure assessment study, were included in biological monitoring surveys of early indicators of genotoxicity. In particular, 65 subjects were enrolled in a study aimed at evaluating the urinary concentrations of 8-hydroxydeoxyguanosine (8-OHdG), a biological marker of oxidative DNA damage, and 23 filling station attendants were selected for a survey of the frequencies of sister chromatid exchanges (SCE) and micronuclei (MN) in peripheral T lymphocytes. In the exposure assessment survey levels of 0.53, 0.71 e 0.32 mg/m3 in the average yearly personal exposure to benzene, toluene and xylenes, respectively, were estimated (individual means based on 6.5 repeated samples per employee). The daily quantities of super premium gasoline sold proved to be associated with the average yearly personal exposure to benzene, and current smokers showed a significantly lower exposure intensity compared with non-smokers. Among the latter, an increase of 0.11 ln mg/m3 in benzene exposure per unit increase (100 l) in gasoline sold (p < 0.001) was estimated by a multiple regression analysis with some personal characteristics of the subjects included in the model as potentially predictive variables (R2 = 0.17, p (F) < 0.05). Among smokers, however, only the age and the length of employment were able to predict the intensity of benzene exposure. On a sample of 27 filling station attendants, furthermore, the relationship between personal exposure to benzene and benzene fuel content was evaluated and an increase of 0.01 mg/m3 in the personal benzene exposure per unit increase (100 g) in the absolute quantity of benzene in the fuel sold was estimated (p < 0.0001, R2 = 0.50).(ABSTRACT TRUNCATED AT 400 WORDS)

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1994

An assessment of the in vivo clastogenicity of erythrosine.

In an investigation of the in vivo clastogenic potential of the food colouring erythrosine (ER), male B6C3F1 mice were treated by ip injection at doses of 50, 100 and 200 mg/kg, repeated 24 hr apart. Signs of toxicity were observed at the highest dose of ER administered. The three cytogenetic endpoints analysed were sister chromatid exchanges (SCEs) in peripheral blood lymphocytes (PBLs), micronuclei in bone marrow polychromatic erythrocytes (PCEs), and micronuclei in peripheral blood reticulocytes (PBRs). SCE frequencies in PBLs were 4.13, 4.58, 4.33 and 4.60 SCE/cell at 0, 50, 100 and 200 mg ER/kg, respectively. At the same doses, the frequencies of micronucleated PCEs were 3.5, 3.2, 2.0 and 2.5/1000 PCEs. Micronuclei in PBRs ranged from 1.2 to 3.6 and from 1.4 to 3.0/1000 PBRs in control and treated mice, respectively. These results indicate that ER is inactive as a clastogen in mouse blood and marrow cells. This result supports the hypothesis of a non-genotoxic mechanism for ER carcinogenicity.

Animals↗
PubMed1994

Simultaneous detection of X-chromosome loss and non-disjunction in cytokinesis-blocked human lymphocytes by in situ hybridization with a centromeric DNA probe; implications for the human lymphocyte in vitro micronucleus assay using cytochalasin B.

A methodology for the simultaneous detection of chromosome loss and gain in mammalian cells has been developed which is based upon the analysis of chromosome distribution in daughter nuclei of binucleated human lymphocytes. X-chromosome distribution was followed by in situ hybridization, using a commercial biotinylated DNA probe specific for the centromeric alphoid sequences of human X-chromosome. In order to optimize the experimental protocol for the use of cytokinesis-blocked lymphocytes in aneuploidy assays, the effect of harvest time and cytochalasin B (Cyt B) dosage upon chromosome distribution was investigated. To this end, lymphocyte cultures were treated 44 h after mitogen stimulation with different dosages of Cyt B and collected at 60, 66 and 72 h. High rates of binucleated cells with unbalanced chromosome distribution (two spots in one nucleus and none in the other in male cells; three spots in one nucleus and one in the other in female cells) and abnormal spot number (more than or less than two per male cell or four per female cell) were observed at 66 and 72 h in cultures treated with the lowest Cyt B dose (3 micrograms/ml). In contrast, low frequencies of unbalanced or abnormal binucleated cells were observed at 60 h with both 3 and 6 micrograms/ml Cyt B. These results indicate that binucleated lymphocytes with low background frequencies of malsegregation (required for the analysis of induced aneuploidy), can be obtained by harvesting lymphocyte cultures 60 h after stimulation (16 h after Cyt B block).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Further in vitro and in vivo mutagenicity assays with thiram and ziram fungicides: bacterial reversion assays and mouse micronucleus test.

The fungicides thiram and ziram have been assayed in a battery of nine bacterial strains of different genetic specificity. The results obtained suggest the induction of excisable DNA lesion(s), and indicate similar mutability of strains with AT or GC base pairs at target sites. This mutagenic profile is clearly distinct from that of oxidative mutagens, and it does not support the proposed role of oxidative stress in the mechanism of dithiocarbamates mutagenicity in bacteria. Furthermore, the bone marrow micronucleus test has been carried out in B6C3F1 mice with intraperitoneal administration of high grade thiram (12.5-50 mg/kg) and ziram samples (2.5-10 mg/kg in males, and 5-20 mg/kg in females). Thiram produced a significant increase of micronucleated PCEs in male mice sampled 48 h after treatment with 25, 37.5, and 50 mg/kg. No significant increase was detected in treated females. Ziram, tested in a lower range of doses because of its higher toxicity, resulted negative in both sexes. Both the acute toxicity and the ratio polychromatic/normochromatic erythrocytes indicated some sex specificity in the toxic effects induced by these dithiocarbamates in the B6C3F1 mouse.

Animals↗
PubMed1992

Diffuse pulmonary lymphangiectasis with heart defect discovered 4 months post-natally.

Congenital pulmonary lymphangiectasia is a rare abnormality with dilatation of pulmonary lymphatics and the radiological pattern of a pulmonary interstitial syndrome. It is usually symptomatic at birth and is almost always lethal. We report the case of an infant with congenital pulmonary lymphangiectasis and congenital heart disease who is still alive at 11 years. This case is interesting from the pathogenic, nosologic and prognostic point of view.

Child↗
PubMed1992

Persistence of a single pulmonary vein in a child.

Persistence of a single pulmonary vein with normal pulmonary venous return is a rape and unusual radiographic finding. We report such a case with the venous opacity partially visible on the right border of the heart on a plain frontal chest film. MRI showed beautifully the pulmonary vein and can now replace angiocardiography.

Angiocardiography↗
PubMed1991

Systemic artery-pulmonary vein fistula without sequestration.

Fistulae between an artery arising from the aorta and a pulmonary vein associated with absence of a branch of the pulmonary artery, but without anomalies of the bronchial tree, are exceedingly rare. We report a case in a child who presented with a continuous vascular murmur and developed heart failure due to the left-left shunt. Left lobectomy was performed and showed that the entire left lower lobe was occupied by a huge arteriovenous fistula between an artery stemming from the aorta and the pulmonary veins.

Aorta↗
PubMed1986

Sensitivity and specificity of radionuclide equilibrium angiocardiography for detection of hemodynamically significant secundum atrial septal defect.

To determine the value of gated equilibrium angiography in secundum atrial septal defect (ASD) in children, the first pass pulmonic/systemic flow ratio (Qp/Qs) was compared with diastolic count ratio (DCR) and stroke count ratio (SCR) of the two ventricles. In 50 children we have found a correlation between Qp/Qs and DCR (r = 0.71) and between Qp/Qs and SCR (r = 0.66). For detection of significant atrial shunt (QP/Qs greater than 1.5) the sensitivity of DCR greater than 2 was 0.81 and the specificity 0.75. For SCR greater than 1.5 we sensitivity and specificity values of 0.87 and 0.71 respectively. Left and right ventricular ejection fractions were normal (0.67 +/- 0.08 and 0.50 +/- 0.07).

Adolescent↗
PubMed1984

[Diffuse pulmonary lymphangiectasia of late disclosure associated with cardiopathy].

Congenital pulmonary lymphangiectasia is a rare abnormality with dilatation of pulmonary lymphatics and the radiological pattern of a pulmonary interstitial syndrome. It is usually symptomatic at birth and is almost always lethal. The authors report the case of an infant with congenital pulmonary lymphangiectasis and congenital heart disease who is still alive. This case report is interesting from the pathogenic, nosologic and prognostic point of view.

Humans↗