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Biomedical subjects

C Giuntini

Publications and source records attributed to C Giuntini.

At least 109 records · Page 6Linked to original sources
PubMed1988

Objective radiographic criteria to differentiate cardiac, renal, and injury lung edema.

To assess the value of the chest radiograph in differentiating various types of pulmonary edema, we retrospectively analyzed 119 films of patients with pulmonary edema caused by left heart decompensation (group 1;N = 56), renal failure (group 2; N = 19), and lung microvascular injury (group 3; N = 44). Chest radiographs were examined independently by two trained observers, unaware of the clinical diagnosis, according to a standardized reading table. The two observers assigned chest films to the corresponding group with an accuracy of 86% and 90%, respectively. To test the observers' objectivity, we used radiographic findings as input variables for discriminant analysis. Computer-generated numerical functions identified pulmonary edema etiology with an accuracy of 88% when considering the three groups together. When groups were compared as pairs, percentages of correct classification were 91% (group 1 vs. group 2), 93% (group 1 vs. group 3), and 100% (group 2 vs. group 3). Thus, a standardized reading of chest radiographs may be considered a reliable clinical method for identifying pulmonary edema etiology.

Heart Failure↗
PubMed1988

Theoretical and practical considerations of measuring extravascular lung water.

The volume of extravascular lung water is currently measured in vivo from the difference in mean transit times of the extrapolated first-pass dilution curves of two indicators, one diffusible and the other confined to the intravascular space. To overcome the limitations of this method, one can prolong the measurement interval, introduce a highly diffusible indicator, or both. In the first case, recirculating indicators are measured and included in the computation by deconvolution of the mean transit time through the lung. In the second case, heat is used as the water indicator. In the third case, not yet explored, recirculating heat would be measured and long thermal transit times uncovered. In view of the complexity of the deconvolution method and the pitfalls of the thermal dilution method, a radiographic score of pulmonary edema may be more useful clinically to assess the volume of extravascular lung water in patients with heart disease or adult respiratory distress syndrome.

Animals↗
PubMed1988

Factors affecting regional pulmonary blood flow in chronic ischemic heart disease.

To assess the effect of left heart disease on pulmonary blood flow distribution, we measured mean pulmonary arterial and wedge pressures, cardiac output, pulmonary vascular resistance, pulmonary blood volume, and arterial oxygen tension before and after treatment in 13 patients with longstanding ischemic heart failure and pulmonary edema. Pulmonary edema was evaluated by a radiographic score, and regional lung perfusion was quantified on a lung scan by the upper to lower third ratio (U:L ratio) of pulmonary blood flow per unit of lung volume. In all cases, redistribution of lung perfusion toward the apical regions was observed; this pattern was not affected by treatment. After treatment, pulmonary vascular pressures, resistance, and edema were reduced, while pulmonary blood volume did not change. At this time, pulmonary vascular resistance showed a positive correlation with the U:L ratio (r = 0.78; P less than 0.01), whereas no correlation was observed between U:L ratio and wedge pressure, pulmonary edema, or arterial oxygen tension. Hence, redistribution of pulmonary blood flow, in these patients, reflects chronic structural vascular changes prevailing in the dependent lung regions.

Blood Volume↗
PubMed1988

Reabsorption kinetics of albumin from pleural space of dogs.

The reabsorption of albumin from the pleural space was measured in eight dogs receiving 0.5 ml intrapleural injection of 131I-labeled albumin and a simultaneous intravenous injection of 125I-labeled albumin. Plasma curves for both tracers were obtained over 24 h. The 125I-albumin curve served as input function of albumin for interstitial spaces, including pleura, whereas the 131I-albumin curve represented the output function from pleural space. The frequency function of albumin transit times from pleural space to plasma was obtained by deconvolution of input-output plasma curves. Plasma recovery of 131I-albumin was complete by 24 h, and the mean transit time from pleura to plasma averaged 7.95 +/- 1.57 (SD) h. Albumin reabsorption occurred mainly via lymphatics as indicated by experiments in 16 additional dogs in which their right lymph ducts or thoracic ducts were ligated before intrapleural injection. A pleural lymph flow of 0.020 +/- 0.003 (SD) ml.kg-1.h-1 was estimated, which is balanced by a comparable filtration of fluid into the pleural space. This suggests that, under physiological conditions, the subpleural lymphatics represent an important control mechanism of pleural liquid pressure.

Absorption↗
PubMed1988

Variability of maximal expiratory flow-volume curve in young volley players.

In order to assess the variability of forced expiratory flows, 15 male players (age 16-19 years, height 182-201 cm) of the Italian National Junior Volley team were studied twice with the pneumotachygraph of the computerized Hewlett-Packard Pulmonary System. The first time (April), but not the second (July), all the subjects were physically trained. Each subject performed at least three acceptable forced vital capacity (FVC) maneuvers, following the standard of the American Thoracic Society, with the exception of the criterion for determining the FVC end point. Mean values of forced mid- and end-expiratory flows were significantly higher in April than in July. Inter- and intrasubject coefficients of variation were lower for FVC and forced expiratory volume in 1 s (FEV1) than for the flows. However, the within-subject variability of expiratory flows is lower in our athletes than in the subjects described by other authors. Our findings indicate the importance of forced expiratory flows in detecting even minor intra-subject variations related to physical training and suggest that flow in the terminal portion of the FVC curve may be at least moderately dependent upon effort.

Adolescent↗
PubMed1988

Fibrinolytic effects of urokinase and heparin in acute pulmonary embolism: a randomized clinical trial.

Dissolution of pulmonary emboli with heparin and urokinase is ascribed, respectively, to anticoagulation and fibrinolysis. Since truly independent assessment of these effects in man is lacking, we administered each drug alone. Fibrinogen and plasminogen plasma levels and the resolution of pulmonary emboli were measured in three randomized groups of 10 patients each: groups A and C infused with small repeated doses of urokinase and a large single dose of urokinase, respectively, and group B who received heparin. After 6 h of treatment, fibrinogen fell in all the groups, while, after 12 h, remained equally reduced in groups A and B and declined further in group C. Plasminogen behaved similarly. Up to 60 h, statistical analysis showed that these effects were related to timing and amounts of urokinase and heparin infusion. These observations suggest that heparin may induce a lytic state. As to signs of pulmonary emboli resolution, no differences between groups were found in lung perfusion and gas exchange recovery at any time (from 1 day to 1 year) and in pulmonary artery pressure reduction at 1 week. The greater angiographic and scintigraphic recovery observed with urokinase, versus heparin alone, after 1 day of treatment in the Urokinase Pulmonary Embolism Trial may be ascribed to a synergistic effect with urokinase of heparin administered during the diagnostic work-out. The indications of heparin and urokinase should be evaluated in the light of these results.

Acute Disease↗
PubMed1988

Pulmonary retention of iodobenzyl-propanediamine in humans. Effect of cigarette smoking.

N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamine (HIPDM), a synthetic basic compound with high affinity for lung tissue of various animal species, was labeled with 123I and injected into normal smokers (n = 9) and into asymptomatic smokers (n = 9). Time/activity curves were recorded for 90 min by gamma camera. HIPDM lung clearance was described by two exponential components. In smokers, the mean time of the first component, 10 +/- 1.4 min (mean +/- SEM), did not significantly differ from that of nonsmokers (9.7 +/- 0.9 min), whereas the mean time of the second component (12.9 +/- 0.6 h) was longer than that of nonsmokers (6.7 +/- 0.2 h). The intercept to the ordinate of the second exponential component was significantly higher in smokers (90.3 +/- 1.5%) than in nonsmokers (80.7 +/- 1.9%). Control studies in rabbits showed that, 2 min after intravenous injection, 95% of HIPDM is taken up by the lung; time/activity curves were similar to those obtained in humans. The longer pulmonary persistence of HIPDM in smokers may reflect an increased number of cellular binding sites or may be the expression of hindered HIPDM biotransformation. The rabbit can be used as a model to further investigate HIPDM kinetics in relation to lung dysfunction.

Adolescent↗
PubMed1988

Single breath nitrogen test in an epidemiologic survey in North Italy. Reliability, reference values and relationships with symptoms.

The usefulness of single breath nitrogen test (SBN2) was evaluated in a cross-sectional epidemiologic survey on a general population sample (n = 3,289) of North Italy. Each subject was submitted to CNR standardized questionnaire and to lung function testing using automated equipment (Hewlett-Packard 47804S). Acceptable closing volume (CV) and slope of alveolar plateau (DN2%/L) tracings were performed by only 1,370 and 1,982 subjects respectively, in comparison with the 2,638 diffusing capacity and the 3,079 forced vital capacity acceptable maneuvers. Prediction equations were computed on normal subjects for CV indices, with the exception of DN2%/L: they were similar to those found in other studies. Significant differences among smoking categories were found for all the SBN2 parameters in males, but only for DN2%/L in females. The latter was also able to distinguish either subjects with airway obstruction from those without it or symptomatic from asymptomatic individuals, but DN2%/L did not give more information than Vmax75, a sensitive index of flow volume curve. Our results suggest that the place of SBN2 in large scale epidemiologic testing has not been justified.

Adolescent↗
PubMed1988

[Short-term prognosis of pulmonary embolism].

Seven hundred fifty four consecutive cases of pulmonary embolism, diagnosed between 1969 and 1982 at S. Chiara Hospital in Pisa, were examined in order to assess the causes and the rate of the early mortality. Full documentation was not obtained in 47 cases (6.2%) and they were excluded from the study; 81 (11.4%) of the remaining 707 died within 30 days of diagnosis, and in 56.8% of them pulmonary embolism was the primary cause of death. The survival rate was 90.6% in patients with apparently primary pulmonary embolism, 89.8% in post surgical cases, 81.5% in cardiac patients and 75% in patients affected by neoplasm. Twenty five per cent of patients were not treated during the acute phase, because the diagnosis was made more than one month after the onset of symptoms or because the fear of bleeding precluded anticoagulant treatment. The incidence of fatal haemorrhage during treatment was 0.5% overall, and 0.4% in surgical patients. Mortality was 9.2% in patients who received treatment, versus 25.2% in untreated patients. Sixteen fatal recurrent embolisms occurred after the end of treatment: 11 were observed in patients not treated with oral anticoagulants. Routine autoptic examinations, performed in 44.4% of the cases, often demonstrated both recent and organized emboli, especially in cardiac patients. Recurrence of pulmonary embolism may account for both the severity of clinical patterns and the high mortality rate in the early phase of treatment.

Female↗
PubMed1988

Prevalence of respiratory symptoms in an unpolluted area of northern Italy.

Using a multistage stratified geographic cluster sample of households living in an unpolluted area of Northern Italy (near Venice), we enrolled 3289 inhabitants (aged 8-64 yr) for a longitudinal respiratory study. During the first cross-sectional survey, before the start of operation of a large oil-burning thermoelectric power plant, they completed a standardized administered questionnaire and performed several lung function tests. In the whole sample, dyspnoea grade 1 (11%), chronic cough and chronic phlegm (9%) were the most frequent respiratory symptoms; all the symptoms except dyspnoea were more prevalent in males than in females. Smokers (S) showed higher prevalence rates than ex-smokers (ES) and nonsmokers (NS), especially in males. In both sexes, the frequency of respiratory symptoms increased with increasing smoking as assessed by pack-years. An inverse relationship between prevalence of symptoms and socio-economic status was also observed. All tests of lung function were significantly impaired in S compared with NS in males; single-breath CO diffusing capacity and slope of alveolar plateau but not spirometric indices were significantly impaired in female S compared to female ES and NS. Finally, our prevalence rates were lower than in other epidemiological surveys: this result may be ascribed to the low levels of air pollution measured in the area.

Age Factors↗
PubMed1987

Pulmonary metabolism of mutagens and its relationship with lung cancer and smoking habits.

The S-12 fractions of lung peripheral parenchyma obtained from 80 male individuals, aged 17-71 years, were assayed as blind samples for the ability either to convert promutagens into bacterial mutagens or to decrease the potency of direct-acting mutagens in the Ames reversion test. In this system, lung preparations were completely ineffective in activating an N-nitroso compound (i.e., N-nitrosomorpholine) and polycyclic aromatic hydrocarbons [i.e., 3-methylcholanthrene and benzo(a)pyrene] or their metabolites [i.e., 3-hydroxy-benzo(a)pyrene and benzo(a)pyrene-trans-7,8-diol]. They yielded a borderline and sporadic activation of a cigarette smoke condensate, and a weak but frequent activation of an aromatic amine (i.e., 2-aminofluorene), of a heterocyclic amine (i.e., 2-amino-3,4-dimethylimidazo[4,5-f] and of a diamide (i.e., cyclophosphamide). The pulmonary metabolism was more oriented in the sense of detoxification, as shown by the consistent decrease of potency of direct-acting mutagens, including a metal (i.e., sodium dichromate), an acridine and nitrogen mustard derivative (i.e., 2-methoxy-6-chloro-9-[3-(2-chloromethyl)aminopropylamino]acridine or ICR 191), an epoxide (i.e., epichlorohydrin) and an N-oxide (i.e., 4-nitroquinoline-N-oxide). As assessed by means of a numerical score quantifying the variation of mutagenicity, a marked interindividual variability (up to 20-fold) was detected in the ability of lung specimens to affect the mutagenicity of test compounds. Such variability was not significantly related to the protein concentration of S-12 fractions, nor to the age of the patients under scrutiny, who during hospitalization were on normal institutional diets and did not receive any special drug treatment. The only significant difference between 20 noncancer and 60 lung cancer patients, irrespective of the histological type, was a decreased activation of cyclophosphamide in the latter group. Probably due to the high prevalence of smokers among lung cancer patients, a significantly decreased activation of cyclophosphamide was also observed in the group of smokers. Smoking habits were associated with a stimulation of detoxifying mechanisms which, in agreement with the results of a previous study with human alveolar macrophages (F. L. Petrilli et al., J. Clin. Invest., 77:1917-1924, 1986), was significant in the case of sodium dichromate. Such effect was further enhanced by considering only individuals smoking during the last 24 h before collecting lung specimens, and under these conditions it became significant also for ICR 191.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Extravascular lung water.

Extravascular lung water (idQw1) is measured in vivo from the difference in mean transit times, computed by extrapolating the dilution curves, of two indicators, one freely diffusible, the other confined to the intravascular space. Using 3H2O it has been shown that idQw1 is smaller than the amount of extravascular water obtained from the difference between wet and dry lung weight (Qw1). Extrapolation allows one to use dilution curves for a short time, i.e., up to onset of obvious recirculation. Clearing the dilution curves or recirculation by deconvolution extends the observation time, which then becomes limited by sampling duration rather than onset of recirculation. This procedure entails recording recirculating tracers in the pulmonary artery (PA). Dilutions of tracers at input in PA and output in a systemic artery must be related to each other as continuous time functions. This is accomplished by means of a convolution integral. Deconvolution yields the frequency function of water molecule transit time in the extravascular lung space, l(t). In dogs and men, in both normal and edematous lungs, l(t) exhibits a knee and a fairly long tail. Extravascular lung water computed from l(t), idcQw1, agrees with Qw1 and correlates with data on the extravascular thermal volume of the lung and with radiographic findings of lung edema. A radiographic score of pulmonary edema may be used clinically to assess extravascular lung water in cardiac patients and in patients with adult respiratory distress syndrome.

Capillary Permeability↗
PubMed1987

Atropine does not inhibit late asthmatic responses induced by toluene-diisocyanate in sensitized subjects.

To determine whether early and/or late asthmatic responses induced by toluene diisocyanate (TDI) are caused by a reflex mechanism involving stimulation of muscarinic receptors, we studied the effect of the muscarinic antagonist atropine on early and late airway response induced by TDI. A preliminary study was conducted in asthmatics to assess whether the selected dose of atropine provided adequate muscarinic blockade. On different days we measured the provocation dose (in milligrams) of carbachol causing a 15% decrease in FEV1 (PD15FEV1) without and with atropine premedication (0.008 or 0.012 mg/kg subcutaneous atropine 30 or 90 min before carbachol challenge test). We found that 0.008 to 0.012 mg/kg subcutaneous atropine increased the PD15FEV1 carbachol by 6- to 10-fold, inducing a consistent and prolonged decrease in nonspecific bronchial hyperresponsiveness to cholinergic agent. Then we examined 10 subjects with a history of sensitization to TDI in 2 sets of experiments. In the first set of experiments, we studied the subjects before and after exposure to TDI (0.04 ppm; 30 min) after no treatment. In the second set of experiments, carried out 1 to 2 wk later, we repeated the same procedure after treatment with atropine (0.008 to 0.012 mg/kg atropine sulfate administered subcutaneously 30 min before TDI challenge, and then at 90-min intervals after TDI exposure); all patients showed symptoms of atropine effect (dryness of mouth, cycloplegia, increased heart rate).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗
PubMed1987

Comparison of algorithms for determining the end-point of the forced vital capacity maneuver.

The criteria of the American Thoracic Society (ATS) for determining the end-point of the forced vital capacity (FVC) maneuver were compared with an algorithm employed by a computer system (Hewlett-Packard), which yields a later end-point. The 150 subjects tested were divided into five groups of 30 on the basis of the following spirometric diagnoses: normal; small airways' obstruction (SAO); mild airways' obstruction (MAO); severe chronic obstructive pulmonary disease (COPD); or restrictive disease. The subjects performed a minimum of three maneuvers according to ATS standards, and the flow-volume curves with the greatest sum of FVC and forced expiratory volume in one second (FEV) were chosen for analysis by the two algorithms. Hewlett-Packard (HP) values for FVC and FVC time were always higher than the corresponding ATS values, and the HP values for flows were always lower than the corresponding ATS values. The higher differences were observed in the SAO group. In the group with severe COPD, high FVC differences and low flow differences were observed; on the contrary, in the restrictive group, low FVC differences and high flow differences were present. These results, in addition to the different location of the FVC end point, may be explained by the different morphology of the flow-volume curves. In conclusion, the ATS algorithm caused a systematic underevaluation of FVC and a systematic overevaluation of flows, which cause practical consequences only in the SAO group. In fact, 28 percent (17/60) of the subjects with SAO characteristics were considered "normal" using ATS criteria for the end-point.

Adult↗