Biomedical subjects

D Choquet

Publications and source records attributed to D Choquet.

58 records · Page 4Linked to original sources

PubMed1985

[Myocardial fibroma. Apropos of a case followed for 11 years].

A case of myocardial fibroma of the left ventricle is described in a young girl. The association of recurrent ventricular tachycardia and radiological deformation of the cardiac silhouette suggested the diagnosis and it was confirmed by myocardial scintigraphy, echocardiography and coronary angiography. At surgery, the tumour was too extensive to be removed. After 11 years follow-up, control of the arrhythmias is satisfactory and there has been no apparent increase in the tumour size. A review of 116 cases in the literature confirms the poor prognosis of myocardial fibroma. The diagnosis was made at autopsy in 60 cases. The 56 remaining patients were operated. Total resection was possible in 37 cases and partial resection in 4 cases. The tumour could not be removed in 15 cases. Overall operative mortality was 35 p. 100 but the prognosis thereafter was good.

Adolescent↗

PubMed1984

[Coronary artery ectasia. Apropos of a case treated surgically in 2 stages].

The authors report a new case of coronary artery aneurysms in a 35 year old man who presented with a rudimentary myocardial infarct. Coronary angiography showed a localized aneurysm of the left anterior descending and left circumflex arteries, and a diffuse dilatation of the right coronary artery. The underlying cause was certainly atheroma because a severe stenosis was observed on the right coronary artery in association with the aneurysm. Five years later aorto-right coronary bypass surgery, when anticoagulant therapy was withdrawn, a second rudimentary infarct occurred due to intra aneurysmal thrombosis on the left circumflex artery. The aneurysmal and atheromatous disease had progressed, justifying a double bypass on the left anterior descending and circumflex arteries with exclusion of the two aneurysms. The patient was reviewed 14 months and 8 years after the first attack of spontaneous angina with good results. This and other reported cases underline the good postoperative prognosis and the necessity for a life-long anticoagulant therapy.

Adult↗

PubMedDate not supplied

Regulation of interleukin-2 production and phosphatidylserine synthesis in Jurkat T lymphocytes by K+ channel antagonists.

Modification of phospholipid metabolism during T cell activation has been repeatedly reported. Recently, we have shown that phytohaemagglutinin, CD3 and CD2 mAbs, which are potent in vitro activators of helper T lymphocytes, markedly inhibit phosphatidylserine synthesis concomitantly as they induce the secretion of IL-2. In this paper, we show evidence that in T lymphocytes K+ channels, which have been shown to participate in the cell activation process, are also reciprocally related to phosphatidylserine synthesis. In fact, in resting T cells the drugs affecting the activity of K+ channels, such as quinine and 4-aminopyridine, induce a rise of phosphatidylserine synthesis. In activated cells, quinine and 4-amidopyridine also caused a rise in phosphatidylserine synthesis which paralleled a decreased production of IL-2, strongly suggesting that these two events are correlated in a reciprocal manner. More precisely, phosphatidylserine synthesis was stimulated by drugs which have been reported to inhibit potassium channels in lymphocytes, e.g. quinine, 4-aminopyridine, tetraethylammonium. These data suggest that the decreased PS synthesis observed during T cell activation intervenes in the cascade of events leading to IL-2 secretion. The decrease in the biosynthesis of this phospholipid seems to be dependent on the activity of K+ channels.

4-Aminopyridine↗

PubMedDate not supplied

Clinical significance of intracavitary spontaneous echo contrast in patients with dilated cardiomyopathy.

To assess the occurrence rate and major determinants of spontaneous echo contrast and to examine its impact on thromboembolic events and mortality in patients with dilated cardiomyopathy, 86 hospitalized patients (73 men and 13 women, mean age 63 +/- 11 years) with dilated cardiomyopathy who underwent transthoracic and transesophageal echocardiographic examinations were followed up for a mean of 20 +/- 13 months. Spontaneous echo contrast was observed in 36 patients (42%) and was detected only with the transesophageal approach. It was seen in the left atrium in 33 patients, in both right and left atria in 1 patient, in both left atrium and left ventricle in 1 patient, and in the descending aorta in 1 patient. Spontaneous echo contrast was more frequent in the presence of atrial fibrillation (p < 0.05), left atrial enlargement (p < 0.02) and severely depressed left ventricular function (p < 0.01), but was less common in patients with moderate to severe mitral regurgitation (p < 0.05). This imaging phenomenon was the only significant independent predictor of intracardiac thrombus formation and previous and subsequent thromboembolic events. During follow-up, there were 26 deaths, and survival in patients with spontaneous echo contrast was significantly lower than in those without it (p < 0.02). A spontaneous echo contrast is commonly detected with transesophageal echocardiography in patients with dilated cardiomyopathy especially in the presence of atrial fibrillation, left atrial enlargement and severe left ventricular dysfunction. This imaging phenomenon represents an important marker for thromboembolic risk and may influence the treatment and clinical outcome of these patients.

Adolescent↗