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Biomedical subjects

C Giuntini

Publications and source records attributed to C Giuntini.

At least 145 records · Page 8Linked to original sources

Metabolic activation and deactivation of mutagens by preparations of human lung parenchyma and bronchial tree.

69 S12 preparations of human lung (43 of peripheral lung parenchyma and 26 bronchial preparations) were assayed for their ability to activate procarcinogens to mutagenic metabolites in the Ames test or to lower the mutagenic response of direct-acting compounds. No sample activated polycyclic aromatic hydrocarbons, such as 3-methylcholanthrene, benzo[a]pyrene or its metabolites 3-hydroxy-B(a)P and B(a)P-trans-7,8-diol, and only borderline effects were observed with cigarette-smoke condensates. Conversely, some activating ability was detected in the case of 2-aminofluorene and of cyclophosphamide. The same samples produced a slight decrease of mutagenicity of epichlorohydrin and ICR-191 and a more pronounced loss of activity of sodium dichromate and 4-nitroquinoline N-oxide.

Biotransformation↗

The vascular pedicle of the heart and the vena azygos. Part I: The normal subject.

The widths of the systemic vessels extending from the thoracic inlet to the heart (the vascular pedicle) and of the azygos vein were measured in 83 normal volunteers and 42 patients with cardiac disease. Mean vascular pedicle width ( VPW ) (erect) was 48 +/- 5.0 mm and correlated well with body weight (r = 0.64) and surface area (r = 0.62). Rotation to the left reduced VPW and to the right increased it. Inspiration and expiration caused little change. The supine VPW increased an average of 20% (47 +/- 37% to the compliant venous right side and 7 +/- 48% to the less compliant arterial left). Supine azygos width (AW) increased 105 +/- 47%. Mean erect AW was 5.14 +/- 1.36 mm. AW did not correlate significantly with anthropomorphic characteristics. Because VPW correlates with the patient's physique, its normality can be estimated within clinically useful limits by inspection. Since AW has no such correlation, serial changes are of more value than initial absolute values.

Adult↗

The vascular pedicle of the heart and the vena azygos. Part II: Acquired heart disease.

To establish the value of the chest radiograph in assessing the hemodynamic status of the systemic circulation, the vascular pedicle width ( VPW ) and vena azygos width (AW) were correlated with total blood volume (TBV) and other parameters in 61 cardiac patients. In both ischemic and valvular cardiac disease a highly significant linear correlation was found between VPW and TBV (r = 0.80, p less than 0.001). In patients with dilated neck veins VPW was greater than 62 mm (normal 48 +/- 5 mm). A less significant correlation was found between VPW and mean right atrial pressure ( MRAP ). Change in VPW correlated strongly (r = 0.93, p less than 0.001) with change in TBV (0.5-cm change in VPW = 1.0-liter change in TBV). Correlation between AW and TBV was poor (r = 0.50, p less than 0.01), but between AW and MRAP the correlation was stronger (r = 0.74, p less than 0.001). Changes in AW usually occurred in the same direction as changes in MRAP , but the correlation was not significant (r = 0.45). VPW and AW did not correlate with pulmonary blood volume, pulmonary arterial pressure, stroke volume, or heart rate. Radiologic assessment of VPW and AW adds an additional clinically useful dimension to the evaluation of cardiac disease.

Azygos Vein↗

The vascular pedicle and the vena azygos. Part III: In trauma--the "vanishing" azygos.

The chest radiographs of 158 patients with widened vascular pedicles were examined. The vascular pedicle was measured and the presence or absence of the right paratracheal stripe and the vena azygos on the radiographs was noted. Increasing the systemic blood volume (or assuming the supine position) causes the vascular pedicle of the heart to widen predominantly to the right, and the vena azygos to enlarge simultaneously. In contrast, extravascular bleeding from aortic damage causes the pedicle to widen predominantly to the left of the midline; at the same time the paratracheal stripe and azygos "vanish." This combination of physiologic and pathologic, and intravascular and extravascular causes of widening of the pedicle. Extravasation of blood or saline from a traumatic right subclavian puncture can cause local bulging of the pedicle to the right and a vanishing azygos. Because the left side of the pedicle remains normal, this can be readily differentiated from an aortic tear.

Adult↗

Pleural liquid pressure gradients and intrapleural distribution of injected bolus.

In supine anesthetized dogs we measured pleural liquid pressure (Pliq) in mediastinal, diaphragmatic, apical, and costal regions at different lung heights during eupneic breathing. At end expiration and at a given height, Pliq was similar in the costal and apical regions, but it was lower in the diaphragmatic and mediastinal compartments. Inspiratory swings toward lower values were progressively greater with increasing height and moving from costal to apical, diaphragmatic and mediastinal compartments. Thus during inspiration, at any height, the costomediastinal and costodiaphragmatic Pliq difference increased while a costoapical difference developed. One minute after injection of 0.5-1 ml of saline at different points within the cavity, end-expiratory liquid pressure became higher on the average by 0.45, 1.55, and 0.55 cmH2O in the apical, mediastinal, and diaphragmatic compartments, respectively, while no change was observed on costal side. These results suggested liquid accumulation in the compartments displaying a lower Pliq. This was confirmed by following, with a gamma camera, on a frontal projection of the lung, the intrapleural distribution of a bolus containing 99mTc-labeled albumin injected at various places.

Animals↗

Pulmonary embolism in neurosurgical patients: diagnosis and treatment.

Pulmonary embolism was suspected in 45 neurosurgical patients who were treated between January, 1980, and December, 1981. Hypoxemia with respiratory alkalosis and sudden tachycardia gave rise to this suspicion more often than any other sign or symptom. Perfusion lung scanning confirmed the presence of pulmonary embolism in 23 of these cases. A retrospective analysis of the clinical course of these 23 patients suggested that one or more previous episodes of pulmonary embolism had occurred in 16 cases (69.6%), and had been either overlooked or misdiagnosed. Treatment was started immediately after diagnosis. Twenty-one patients were given heparin; however, two could not be treated because of contraindication to using anticoagulant drugs. Two patients died during treatment. The 21 surviving patients were assessed and 11 of them submitted again to perfusion lung scanning 1 week after diagnosis: 14 had improved, but seven did not show significant changes either clinically or on perfusion lung scanning. Nine treated patients developed hemorrhage, but it was readily controlled. In two of the nine patients, hemorrhage involved the surgical area. It is stressed that pulmonary embolism may be suspected and diagnosed in neurosurgical patients at an early stage. Heparin may be given and the survival rate appears to be better than previously reported figures.

Adolescent↗

A controlled clinical trial on the effect of heparin infusion and two regimens of urokinase in acute pulmonary embolism.

A comparison of the effects of two regimens of urokinase infusion not associated to heparin and of continuous heparin infusion was made assessing the rate of emboli and arterial hypoxemia resolution in patients with acute pulmonary embolism. Twenty-nine patients with acute pulmonary embolism, each one diagnosed by means of perfusion lung scan and selective pulmonary arteriography, were admitted to the study and randomly allocated to three treatment groups: A, 10 patients, urokinase: 800,000 CTA units/day for three days followed by oral anticoagulants; B, 9 patients, heparin: mean daily dose 30,000 units for seven days followed by oral anticoagulants; C, 10 patients, urokinase: 3,300,000 CTA units in 12 hours followed by oral anticoagulants. Pulmonary lung scan and PaO2st (PaO2 standardized to PaCO2 of 40 mmHg) were repeated at 1, 3, 7, and 30 days in all the groups of treatment. The mean daily rate of improvement, assessed from both the perfused lung segments and the PaO2st increment, in group C was highest in the first 24 hours and lowest from the first to the third day of treatment. However, from the third to the seventh day of treatment and onwards the mean daily rate of improvement was roughly the same in all the groups. After one month, lung perfusion and the PaO2st had considerably improved, but had not attained full recovery in any of the treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

Enlargement of the right descending pulmonary artery in pulmonary embolism.

Pulmonary embolism often is undetected during life, even though adequate diagnostic procedures are available, probably because the condition is not suspected. Chest radiographs were reviewed for changes in the right descending pulmonary artery in 73 patients with confirmed pulmonary embolism and in 85 in whom the original suspicion subsequently was not confirmed. In embolic patients, the vessel, measured at four different levels starting from the superior venous angle, was larger during acute embolization than some weeks later. In particular, the two proximal diameters of descending pulmonary artery were significantly enlarged (p less than 0.01). This enlargement of the superior part was responsible for the shape modification of the vessel, which appeared to taper off sharply. Some weeks later, the artery took back its regular cone shape, tapering gently. In about one-fourth of the patients with pulmonary embolism, enlargement and shape modification were so marked that the artery showed a special "sausage" appearance. This feature did not occur in patients with unconfirmed suspicion of pulmonary embolism. Recognition of enlargement of the descending pulmonary artery may increase suspicion of pulmonary embolism; in particular, detection of "sausage" appearance of the vessel should identify patients with high probability of disease.

Adult↗

Venous obstruction in permanent pacemaker patients: an isotopic study.

Isotope venography was used to study the venous circulation proximal to the superior vena cava in two groups of pacemaker patients, one with a single endocavitary electrode and the other with multiple pacing catheters. A control group of patients without pacemakers was also studied. Numerous abnormalities were found, especially in the group with multiple electrodes. These findings suggest that venous obstruction is a common complication of endocardial pacing.

Cardiac Pacing, Artificial↗

Chest tomography by gamma camera and external gamma source: concise communication.

To obtain tomographic images of the chest, we used a large-field gamma camera to detect the 90 degrees scattered radiations (180 keV) from a linear source of Hg-203 (279 keV). The primary beam traveling across the chest is scattered according to the relative density of tissues. Chest sections can be visualized at different depths on frontal and sagittal planes. The resolution of the technic is that of the gamma camera.

Gamma Rays↗