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Biomedical subjects

P de Groote

Publications and source records attributed to P de Groote.

52 records · Page 3Linked to original sources
PubMed1993

Subclavian angioplasty: immediate and late results in 50 patients.

In order to assess the therapeutic outcome of percutaneous transluminal angioplasty for subclavian stenosis, 50 patients were followed up clinically as well as with a velocimetric Doppler after attempted angioplasty. A minimal clinical follow-up of 9 months was expected. Subclavian stenoses were due to atheroma in 49 patients and to Takayasu's disease in 1 case. Indication of angioplasty was curative in 34 (68%) symptomatic patients (posterior fossa ischemia and/or upper limb ischemia) and preventive in 16 (32%) asymptomatic patients (severe difference of blood pressure between the 2 arms and/or association with carotid stenosis or axillo-femoral bypass). Angioplasty was successful in 45 patients (primary success rate = 90%). Three (6%) thrombosis occurred due to the percutaneous approach, one of the axillary and one of the brachial artery without any significant sequelae, and one of the aorta requiring an aorto-bifemoral bypass. A complication occurred in 2 unsuccessful angioplasties (4%): an ischemic stroke occurred in 1 case and a thrombosis of the dilated site requiring a surgical bypass. Clinical follow-up over a period of 9-101 months (mean = 41) was performed in 43 out of the 45 patients who had undergone angioplasty successfully. Two patients had a follow-up shorter than 9 months: one died after 5 months, the other was lost to follow-up. By the end of the clinical follow-up, 37 (84%) out of the 44 followed-up patients had benefitted from the procedure. Doppler study performed in 35 out of the 44 followed-up patients (80%) over a period of 2-90 months (mean = 39) showed 5 restenosis (14%). This study demonstrates the good long-term results of angioplasty in case of subclavian artery stenosis. Though there are complications, angioplasty could be proposed as a first choice treatment for subclavian stenosis as compared to surgery. Indications in asymptomatic patients should be carefully weighed as complications may occur.

Angioplasty, Balloon↗
PubMed1993

Disulfide bonds in folding and transport of mouse hepatitis coronavirus glycoproteins.

We have analyzed the effects of reducing conditions on the folding of the spike (S) protein and on the intracellular transport of the membrane (M) protein of the mouse hepatitis coronavirus. These proteins differ in their potential to form disulfide bonds in the lumen of the endoplasmic reticulum (ER). Intrachain disulfide bonds are formed in the S protein but not in M, which was demonstrated in a pulse-chase experiment by analyzing the viral proteins under nonreducing conditions. To reduce disulfide bonds in vivo, we added dithiothreitol (DTT) to the culture medium of mouse hepatitis coronavirus-infected cells following a procedure recently described by Braakman et al. (I. Braakman, J. Helenius, and A. Helenius, EMBO J. 11:1717-1722, 1992). Short exposure to DTT resulted in the complete reduction of newly synthesized S protein and affected its conformation as judged by the change in mobility in nonreducing gels and by the loss of recognition by a conformation-specific monoclonal antibody. Using this antibody in an immunofluorescence assay, we monitored the reducing effect of DTT in situ. DTT was found to initially affect only the S protein present in the ER; also, after longer treatment, the remaining signal also gradually disappeared. In contrast, folding and transport of the M protein were not inhibited by DTT. Under reducing conditions, M was transported efficiently to the trans side of the Golgi complex, indicating that cellular processes such as ER-to-Golgi transport, O-glycosylation, and Golgi retention were unaffected. In the presence of DTT, the M protein even moved at an increased rate to the Golgi complex, which is probably because of its failure to interact with unfolded S protein. The effects of in vivo reduction were reversible. When DTT was removed from pulse-labeled cells, the S protein folded posttranslationally and aberrantly; during its oxidation, most of S now transiently aggregated into large disulfide-linked complexes from which subsequently folded S molecules dissociated.

Biological Transport↗
PubMed1993

[Pericarditis disclosing at adult age recurrent Still's disease in childhood].

A 29 year old patient with a history of juvenile rheumatoid arthritis had a recurrence 12 years later, presenting as pericardial effusion with cardiac tamponade. Cardiac tamponade is a rare complication of Still's disease. To the author's knowledge, it has never been described as the mode of presentation of adult Still's disease. The diagnostic difficulties and inefficacy of non-steroid anti-inflammatory agents are illustrated by this case.

Adolescent↗
PubMed1993

[Evaluation of embolic cerebrovascular complication: contribution of transesophageal echography].

Ischemic cerebrovascular accidents are classically attributed to an embolism of cardiac origin in 15% of cases. This longstanding concept is questioned by trans-esophageal echocardiography (TEE). The incidence of anomalies which could be the origin of a cerebral embolism involves more than 50% of cases in certain series. The superiority of TEE over trans-thoracic echocardiography (TTE) emerges in particular when certain abnormalities such as an intra-atrial thrombus, spontaneous atrial contrast, an intra-aortic atherosclerotic plaque, a patent foramen ovale or an aneurysm of the inter-atrial septum are sought. The high incidence of such abnormalities in a population having sustained an ischemic cerebrovascular accident is not sufficient to establish a cause-and-effect relationship between the abnormality and the cerebral event. Certain abnormalities are commonly associated with each other or with emboligenic arrhythmias (atrial fibrillation). Studies hence remain required to determine the respective responsibilities of these various abnormalities and stratify their embolic risk by defining certain risk factors. While awaiting the result of such studies, it would seem valid to suggest the more routine use of TEE in the investigation of ischemic cerebrovascular accidents in young patients free of clinically obvious heart disease, and this regardless of the result of TTE.

Heart Diseases↗
PubMed1993

[Rhabdomyolysis caused by pravastatin and type 1 macrocreatine kinase].

The authors report a case of rhabdomyolysis which occurred in a 61 year old woman who was receiving pravastatin and who was also found to present with type 1 macrocreatine kinase. Drug induced rhabdomyolysis is common, particularly with HMG Coenzyme A reductase inhibitors. The authors describe the onset of an adverse effect of this type with pravastatin, a recently marketed drug, as has been previously described for lovastatin and simvastatin. The concomitant detection of macrocreatine kinase, the incidence of which is estimated to be between 2 and 5% in the population, raises the question of whether rhabdomyolysis of this type may occur preferentially in patients with this biological anomaly.

Creatine Kinase↗
PubMed1992

Malignant pericardial effusions: usefulness of pericardioscopy.

In cases of malignant pericardial effusion, surgical subxiphoid biopsy sometimes fails to prove malignancy. To assess the usefulness of pericardioscopy, which allows an endoscopic investigation of the pericardial cavity, this technique was systematically performed during surgical drainage procedures that were performed on 40 patients who had pericardial effusions of suspected malignant origin. Twenty-six patients had a history of neoplasm, 10 had a history of hematologic malignancy, and four had recent tumors or lymphadenopathies that were suspected to be of malignant origin. Classical tests that are usually performed during a conventional surgical drainage procedure (fluid studies and subxiphoid biopsy) were combined with direct visualization of the pericardial surfaces and guided biopsies of suspicious areas. The follow-up period after pericardioscopy was at least 12 months. Two early deaths occurred after pericardioscopy, but no death was directly related to the endoscopy. According to all of the tests that were performed, diagnoses were malignant pericardial effusion in 15 of 40 patients (group I, 37%) and nonmalignant pericardial effusion in 25 of 40 patients (group II, 73%). In 3 of 13 patients (23%) in group I, the diagnosis was obtained only by pericardioscopy (results of cytologic studies and subxiphoid biopsy were negative). In two patients in group I, pericardioscopy could not be completed, but the diagnosis of malignant pericardial effusion was obtained by pericardiocentesis. In group II, effusion was considered to be postradiation pericarditis in five cases, infectious pericarditis in three cases (bacterial in one and tuberculous in two), hemopericardium induced by coagulation disturbances in three cases, and idiopathic pericarditis in 14 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1992

Proto-oncogene expression in rabbit aorta after wall injury. First marker of the cellular process leading to restenosis after angioplasty?

In order to study the earliest phenomenons occurring in the arterial wall after balloon angioplasty, the level of expression of the proto-oncogenes, c-fos and c-myc, was studied in rabbit aorta after balloon denudation by using Northern blot analysis. Both c-fos and c-myc are rapidly and transitorily induced (maximal at 30 min and 2 h after mechanical injury for c-fos and c-myc respectively). By comparison, infusion of norepinephrine increases oncogene expression in normal non-denuded rabbit aorta after 1 h, but the combination of both mechanical and hormonal stimuli do not lead to a more important induction than balloon denudation alone.

Angioplasty, Balloon↗
PubMed1992

[Left intraventricular gradients measured by Doppler echocardiography at rest, during exercise and during isoproterenol test in hypertrophic cardiomyopathy].

Doppler echocardiography has been shown to be an accurate method of assessing left ventricular outflow obstruction in hypertrophic cardiomyopathy (HCM). One of the characteristics of this pressure gradient is its variability and, therefore, we measured this parameter during dynamic exercise testing in 33 patients. The results were compared with those recorded during isoproterenol infusion, the reference stress test for patients with HCM. Submaximal exercise in the recumbent position is usually well tolerated and resulted in a 43% increase in heart rate and a 47% increase in pressure gradient. There was a significant correlation between resting and exercise outflow obstruction (r = 0.90; p = 0.001). Moreover, exercise echo revealed obstruction in 26% of patients without resting pressure gradients (latent obstruction). The interpretation of results obtained with isoproterenol infusion is more difficult: this test resulted in an important increase in the left ventricular pressure gradient (231%) and "revealed" obstruction in 84% of cases. Therefore, we believe that exercise is more physiological and better tolerated than isoproterenol stress infusion and should be adopted as the investigation of choice in HCM even without obstruction at rest. If it is not possible to perform the exercise or no outflow tract obstruction can be demonstrated, an isoproterenol infusion may be used but this is not always well tolerated and the results should be interpreted with caution.

Cardiomyopathy, Hypertrophic↗
PubMed1989

[Kidney angioplasty. Long-term clinical and angiographic results apropos of 50 patients].

In order to evaluate the long-term results of renal angioplasty with a follow-up of at least 3 years, we reviewed the first 50 patients who were treated by this technique for renovascular hypertension. The 42 patients (85 p. 100) in whom the angioplasty was technically successful were followed up both clinically and radiologically, using intravenous digital angiography. The clinical follow-up lasted 52 months on average (range: 8 to 96 months) and reached 3 years or more in 37 patients (4 patients died and 1 was lost sight of). The hypertension returned in 19 of the 42 patients (45 p. 100), the relapse occurring after 24 months in 8 cases. Thirteen of these patients accepted a control angiography which showed restenosis in 11 cases. At the end of the follow-up period, and after a second dilatation in some cases, 30 (60 p. 100) of the 50 patients were found to have benefited from the angioplasty (20 p. 100 were cured and 40 p. 100 were improved). 80 p. 100 of the patients whose renal artery stenosis was due to fibromuscular dysplasia (n = 10) were cured or improved, as were 66 p. 100 of the patients with "localized atheroma" (n = 12), but patients with severe and diffuse atheromatous lesions (n = 28) did not respond so well (7 p. 100 cured, 43 p. 100 improved), and all the major complications of the procedure occurred in this group. The radiological follow-up was performed in 36 patients over a mean period of 31 months (range: 1 to 96 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Heart valve involvement in lupus erythematosus disseminatus. Apropos of 2 cases. Review of the literature].

Regarding two cases of idiopathic lupus valvulopathy, the authors review the various mechanisms responsible for the endocardial lesions in disseminated lupus erythematosus. In addition to the classic Libman-Sachs endocarditis, there are sclerous forms, ruptures of the chords, thromboses and bacterial superinfections. The role of steroid therapy in the genesis of valvular stenosis is not always determined. A surgical treatment, effective and without major risk, must be advocated at an early stage in the presence of poorly tolerated forms.

Adrenal Cortex Hormones↗
PubMed1988

[Value of pericardioscopy in pericardial effusion. Apropos of 20 patients].

The value of pericardioscopy in pericardial effusion of uncertain origin was evaluated in 20 patients, aged from 18 to 77 years, whose pericardial effusion had been diagnosed by ultrasonography; 2 patients presented with clinical signs of tamponade. The cause of the pericarditis was unknown, but the clinical context suggested a malignant disease in 13 patients, tuberculosis in 5 patients and another cause in 2 patients. The pericardium was explored by means of a direct vision, cold-light endoscope, usually a mediastinoscope, introduced by the retroxiphoidal route under general of local anaesthesia. This method made it possible to study the pericardial fluid, examine the pericardial serous membrane, perform biopsies at a distance from the orifice of entry and cleanse the pericardium thoroughly in cases with blood or pus collection. Apart from 2 cases where the examination could not be completed because of an anterior mediastinal mass and a pericardial symphysis, valuable information could be obtained in purulent pericarditis (n = 1), chronic radiation induced lesions (n = 2), metastases (n = 2), haemopericardium (n = 2), and biopsies could be performed in tumoral or suspicious areas. These guided biopsies revealed a metastasis in 3 cases where the pericardial window was negative. No sign of tuberculosis was found in the 5 cases where the disease was suspected. The final diagnoses were: neoplastic pericarditis in 4 cases, radiation-induced pericarditis in 2 cases, purulent pericarditis in 2 cases, haemopericardium in 3 cases and idiopathic or reactive pericarditis in 9 cases. The post-operative period was uneventful, with no major complication ascribable to the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

[Chronic aortic dissection disclosed by pericardial effusion. Apropos of 3 cases].

Three exceptional cases of chronic aortic dissection revealed by a pericardial effusion are reported. The patients were two men and a woman admitted for thoracic pain or fever. Initial diagnoses were myocardial infarction, infective endocarditis and tuberculous pericarditis. The effusions were drained on two occasions. Because the pericardial fluid was a mixture of serum and blood, computerized tomography of the thorax and abdomen was performed. All three cases were then diagnosed as aortic dissection (type II in two cases and type III in one case, with retrograde extension to the ascending aorta). The authors underline the utility of drainage and the need for systematic CT scans in patients with sero-haematic pericardial effusion of uncertain origin.

Aged↗