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Biomedical subjects

L Rossi

Publications and source records attributed to L Rossi.

At least 505 records · Page 28Linked to original sources

[Aorto-coronary by-pass: pre and post-operative ergometric evaluation of 95 patients (author's transl)].

95 angina patients surgically treated by aortocoronary saphenous vein by-pass, have been studied by comparing the factors limiting the exercise (i.e. muscular exhaustion, angina, electrocardiographic changes), the total work performed, the O2 consumption and the heart rate-arterial pression product. After surgery the incidence of positive effort tests (effort angina and/or ecg evidence of myocardial ischemia) decreased from 79% to 27,4% (p less than 0,001), and the average amount of work performed increased from 2718 to 3504 Kgm (p less than 0,01), the MVO2 from 13,9 to 15,6 cc/min/Kg. (p less than 0,01) and the heart rate-arterial pression product from 206 to 243 (p less than 0,001). The patients who preoperatively were more invalidated (that is able to performe a lasser amount of physical work) presented a more pronounced improvement in comparison with those who had a greater tolerance to exercise. It seems therefore that for these latter patients the bypass grafting surgery should be justified only if a significant increase of life expectancy and reduction of myocardial infarction incidence could be definitely proved. The exercise performance improvement after surgery was statistically significant only in the patients with post infarction or with unstable angina not in those with chronic angina. The perioperative infarction (present in 8,4% of cases) did not show any unfavorable correlation with the result of the late postoperative effort test.

Adult↗

[Studies of the expectancy wave (CNV) in patients with interruption of the thalamo-prefrontal interconnnection pathways caused by psychosurgical prefrontal lobotomy operations].

Frontal and vertex CNVs were studied in 8 selected nonschizophrenic patients subjected to unilateral or bilateral extensive prefrontal lobotomy. The dorsomedial thalamo-frontal pathways had been severed and their regeneration must be considered impossible. Standard CNV task (S1-S2-R) was followed in order to elicit CNVs from the frontal areas anterior to the line of sections and at Cz. In 7 out of 8 patients it was quite easy to evoke CNV with almost normal features and equal latencies in each case from all the cortical areas explored. These results show that CNV formation is not grossly altered in the prefrontal areas which have been irreversibly deprived of normal bi-directional mediothalamic-frontocortical connnections. This suggests that the role of the dorsomedial thalamo-frontal pathways are not essential in the genesis of the frontal CNV in humans. These findings would suggest that the CNV is a diffuse electrical event essentially related to a unitary cerebral process mediated fundamentally by nonspecific ascending meso-diencephalic reticular systems. The differences in morphology and polarity of the CNVs detectable in various brain structures are presumably related to their intrinsic anatomo-functional characteristics and to the method commonly utilized in recording the CNV.

Adult↗

Long-term administration of DDT or phenobarbital-Na in Wistar rats.

In lifespan studies, outbred male and female Wistar rats were given either technical DDT mixed into the diet at a dose of 500 parts per million (ppm) or phenobarbital-sodium dissolved in drinking water at a dose of 500 ppm. Liver-cell tumors developed in treated animals but not in controls. The incidence of liver tumors was 45% in the DDT-treated group and 44% in the phenobarbital-sodium-group. When evaluated by sex, DDT-treated females and males had incidences of 56% and 35%, respectively, while in the phenobarbital-sodium group, the respective incidences were 32% and 59% in females and males. These data show a varying susceptibility between the sexes, with regard to induction of liver-cell tumors by the two compounds. In both treated groups, the number of nodular tumors per rat and the average size increased with age and were greater in females. None of these tumors and metastasized. Histologically, the liver tumors were nodular growths, which compressed surrounding parenchyma did not infiltrate it. The total incidence of extrahepatic tumors was higher in controls than in treated animals. In this connection, we must mention the apparent, but not significant, reduction of adrenal tumors in treated rats compared to the controls.

Age Factors↗

Dysrhythmias and sudden death in acromegalic heart disease. A clinicopathologic study.

A clinicopathologic investigation was carried out in a patient with acromegaly from acidophylic adenoma of the hypophysis. Pronounced cardiomegaly and disturbances in impulse formation and conduction led to sudden death. The problem of acromegalic cardiomyopathy has been reviewed. Particular attention has been focused on the histopathologic findings in the working and specific myocardium, and in the intrinsic nervous supply to the sinoatrial node, which were correlated with the electrocardiographic features of atrioventricular conduction delay and sick sinus syndrome.

Acromegaly↗

[Bypass aorto-coronarico. Correlazione tra dati clinici, emodinamici ed angiografici e risultato operatorio in 100 casi (author's transl)].

In 100 consecutive patients, subjected to myocardial revascularization by aorto-coronary saphenous vein bypass grafting with a standard technique, several clinical, hemodynamic and angiographic data were studied in correlation with the short-term prognosis. The operative mortality (6% on the whole) appeared to be strictly correlated with the degree of left ventricular impairment. Among the considered hemodynamic indices (LVEDP, CI, EDV, EF), EF was the most significant one: mortality was 0% if EF was normal, but raised to 15 and 40% respectively, when this was moderately or severely reduced. The operative risk was heavily aggravated if 4 or more indices of left ventricular impairment were present, mortality being 45% versus 1% in patients with abnormality of 3 or less parameters. The extension of coronary artery involvement proved to be a lesser prognostic factor than the degree of complements of the surgical revascularization. No correlation was found between the preoperative value of the hemodynamic parameters and the incidence of perioperative myocardial infarction (18% in the total series).

Adult↗

[Motor nerve conduction velocity in arterial hypertension].

Motor nerve conduction velocity was studied in a group of 44 hypertensive patients; velocity was measured at the level of the median and external popliteal sciatic nerves. From the series were excluded those hypertensive subjects with renal insufficiency, diabetes mellitus and peripheral arterial disease. No significant differences were observed in MNCV values compared to controls. Within the hypertense group, no appreciable variations were observed depending on the duration and degree of hypertension, and signs of visceral damage (assessed at myocardial and retinic levels). The results do not confirm previous published data suggesting the existence of MNCV reduction during arterial hypertension, the reduction being considered an subclinical expression of peripheral neuropathy and an index of the gravity of visceral damage during hypertensive disease.

Adult↗

The roles of age at treatment and dose in carcinogenesis in C3Hf/Dp mice with a single administration of N-nitroso-N-methylurea.

C3Hf/Dp mice were given a single i.p. injection of 50, 25 or 5 mug/g N-Nitroso-N-Methylurea (NMU) at either 1 or 70 days of age or 50 mug/g at 21 days of age. They were observed until death or until 120 weeks of age. The two highest doses of NMU produced tumours in a wide spectrum of organs, including the thymus, forestomach, lung, liver (only in males), kidneys, ovaries and orbital glands. The only two tumour types which appeared to be closely related to the occurrence of death were thymic lymphomata (most of which were found in mice dying before 40 weeks after treatment) and carcinomata of the forestomach. Lifetime analyses are presented concerning the occurrence of these two tumour types as well as the occurrence of any tumour after 40 weeks of age or since treatment. Incidences of thymic lymphomata were 67.6%, 39.0% and 21.2% in mice receiving 50 mug/g NMU at 1, 21 and 70 days respectively and 17.1% in mice receiving 25 mug/g at 1 day. In the other groups the incidence of thymic lymphomata was zero or negligible. The rate of progression of thymic lymphomata until death was related to both earliness of treatment and dose. On the contrary, incidences and progression of carcinomata of the forestomach were unrelated to age at treatment. Since breakdown of NMU is very rapid and does not require enzymes, these results are considered as evidence that host-tumour interaction differs from organ to organ. No excess of tumours over the controls was found in mice receiving 5 mug/g either at 1 or 70 days of age.

Age Factors↗

Histopathology of conducting system in left anterior hemiblock.

In 8 cases of left anterior hemiblock, combined with right bundle-branch block in 7, serial sections of the conducting system of the heart were examined histologically. In all cases there were pathological changes in the left bundle-branch but the anterior part of it was predominantly affected in only 2 cases. Acute changes were found in 6 cases of early myocardial infarction, and fibrosis in 2 cases of chronic heart disease. Reversible lesions may have a pathogenetic role in acute hemiblocks. The right bundle-branch was disrupted by fibrosis in 6 of the 7 cases with right bundle-branch block, and minor changes in the AV node were observed in 1. The widespread damage to the left bundle-branch in the majority of the present cases does not seem to be consistent with the limited clinicopathological correlation implied by the terms anterior fascicular block or hemiblock. Other cardiac lesions within the left bundle-branch and outside it may contribute to this electrocardiographic pattern.

Adult↗

Histopathological findings in two cases of torsade de pointes with conduction disturbances.

Histological studies were made of the conducting system and the myocardium in two cases of torsade de pointes with complex disturbances of impulse conduction and formation. A fairly similar clinicopathological pattern was seen, consisting of an unusual association of non-interruptive, widespread damage to the conducting system with the intermittent and variable electrocardiographic disorders. The inherent desynchronization of cardiac action and the bilateral, uneven, and partial disruptions of the bundle-branches have been tentatively correlated, pathophysiologically, with the re-entry circuit, or mechanism, which is held to be responsible for the cyclic fluctuation of QRS axis, peculiar to torsade de pointes.

Aged↗

Multiple lesions of the conduction system in a case of cardiac rhabdomyosarcoma with complex arrhythmias. An anatomic and clinical study.

Anatomic and electrocardiographic correlations in a case of primary cardiac rhabdomyosarcoma are examined. Interatrial and atrioventricular conduction disturbances were associated with multiple lesions involving the alleged internodal pathways, together with atrial-atrioventricular nodal connections. The clinicopathologic findings seem to be consistent with the hypotheses of the functional and morphologic value of Bachmann's fascicle, and of the inherent pathways of interatrial and internodal conduction in health and disease.

Adult↗

[A histo-cytological contribution to the knowledge of atrial internodal connections (author's transl)].

The problems, still widely discussed, concerning the demonstration of specific internodal conducting pathways in the right atrium have been reviewed, in the light of histo-cytological findings on the initial tracts of Bachmann's (anterior) and Thorel's (posterior) bundles in 7 human hearts. The evidence of Purkinjan cells and of small myocytes, together with the richness in connective tissue and nervous component, make these tracts clearly distinguishable from the common myocardium and seem to substantiate the thesis of morphologically discrete internodal connections.

Adult↗

[Vectorcardiographic contribution to the differential semeiology of cardiomyopathies (author's transl)].

The electro-vectorcardiographic findings of 59 patients with idiopathic cardiomyopathies, divided by means of hemodynamic and angiographic study into dilated (38 cases), hypertrophic obstructive (10 cases) and hypertrophic non obstructive (11 cases), were compared with those of a control group of 17 patients with left ventricular hypertrophy of known etiology. The statistical vectorial analysis of the 4 groups, excluding the patients with intraventricular conduction disturbances and patients below 10 years of age (46 cases), showed low voltage of the first vectors, especially at 0,01 sec., in the obstructive compared with the non obstructive type. On the basis of the data from the literature on histological findings in cardiomyopathies, these differences can be interpreted as due to a different myofibrillar arrangement in the free wall of the left ventricle.

Arrhythmias, Cardiac↗

[Correlation between serum values of copper, ceruloplasmin, SMAO, SDAO, in health- subjects, in pregnant women and in some pathological conditions (author's transl)].

Copper directly reactive with diethylditiocarbamate, ceruloplasmin, monoamine oxidase (SMAO) and diamine oxidase of the serum (SDAO) were studied in healthy subjects, in nine months pregnant women and in some pathological conditions. Increased values of copper were found in pregnancy. Ceruloplasminaemia was increased in hyperthyroidism, congestive hearth failure, Hodgkin's disease, and in pregnancy. Ceroluplasminaemia was strongly reduced in Wilson's disease. SMAO was increased during pregnancy. Statistical analysis showed no correlations between the variations of the data in different pathological conditions. In healthy subjects and in pregnant women, correlation was found between the values of ceruloplasmin obtained using both enzymatic and KCN methods. Statistical analysis of regression lines obtained in both groups of patients showed significative differences between slopes and elevations. It is possible that ceruloplasmin in pregnant women has different composition compared with healthy controls.

Adolescent↗