Search PubMed⌕ Search

Biomedical subjects

L Capron

Publications and source records attributed to L Capron.

At least 109 records · Page 6Linked to original sources

[Epidemiology and risk factors of cerebral arterial accidents].

In France, available epidemiologic data (mortality statistics, Paris prospective study)--although still insufficient--indicate: 1) that arterial strokes account for about 13 per cent of all deaths, and 2) that their annual incidence in men aged 40 to 60 is around 0.6 per thousand and increases sharply thereafter. These results are comparable to those of other industrialized countries, with the exception of Japan where the actual incidence of arterial strokes seems to be higher. Age and high blood pressure are the major risk factors and causes of the various types of ischaemic and haemorrhagic arterial strokes. Several studies suggest that the treatment of hypertension significantly decreases the incidence of arterial strokes.

Adult↗

Diabetes and insulin: actions and interactions upon the glucose metabolism of rat aorta.

We studied the glucose oxidation to CO2 and the incorporation of glucose into lipids by thoracic aorta from streptozotocin-diabetic rats in two circumstances: 9 minutes exposure of the isolated aorta to insulin, perfused in situ; and one-week treatment with either low--4 units (U)--or high--12 U--daily doses of insulin. Diabetes inhibited the glucose metabolism of media and adventitia. Perfusion with insulin did not influence the depressed metabolism of media but increased that of adventitia. Four units insulin treatment normalized the synthesis of glucose-derived lipids by the media, whereas 12-U treatment brought it to levels significantly higher (+23%) than those found in nondiabetic rats. We conclude that: (a) a haemodynamic explanation cannot account for the in vitro insulin resistance of media found in diabetes; (b) insulin treatment exerts a dose-dependent lipogenic effect upon the media, which might favour an atherogenic role for therapeutic hyperinsulinaemia in insulin-dependent diabetics.

Animals↗

[Atherosclerosis. Description and mechanisms. Part 1: description].

This review is devoted to the cellular biology of the arterial wall, particularly of the cerebral arteries. Starting with the description of the structure and physiology of normal arteries and of atherosclerotic lesions some of the current theories on the mechanisms of atherosclerosis are considered. They have developed along two lines of thinking according to whether the main role is given to arterial smooth muscle cells or to macrophage cells. Both hypotheses view atherosclerosis as a pathological deviation from a physiological reaction aimed at maintaining and repairing the permanently strained arterial intima. The risk factors, as identified by epidemiological studies, are likely to play a major role in this degenerative process.

Arteries↗

[Takayasu's disease. Diagnostic criteria (author's transl)].

Retrospective analysis of the records of 86 patients with Takayasu's disease confirmed that the condition is more common in women, that it is frequently associated with a history of tuberculosis and that angiography is of considerable help in showing vascular lesions that are characteristic by their location (common carotid artery, post-vertebral subclavian artery) and by their diffusion to various areas. Histological examination of 20 surgical specimens confirmed the diagnostic value of sclerosis of the media and adventitia (associated or not with inflammatory lesions) and therefore radically different from the lesions of the intima observed in Horton's disease. Diagnostic criteria based on clinical, radiological and histological data are proposed.

Aortic Arch Syndromes↗

[Systemic scleroderma : salivary immunoglobulins and the Gougerot-Sjögren syndrome].

The concentrations of immunoglobulins (Ig) A, G and M were measured in saliva using an electro-immunodiffusion technique at pH 5 with carbamylation of the antisera. Thirty-one controls and 20 patients with generalised scleroderma (10 with and 10 without Sjögren's syndrome) were studied. The three classes of immunoglobulins were in normal saliva. A concentration of IgG greater than 55 mg/l in whole saliva was associated with Sjörgren's syndrome. This is the consequence of the reduction of the rate of saliva production, as well as an increased local synthesis of IgG. The measurement of IgG in unconcentrated saliva could be useful in the detection of Sjögren's syndrome.

Humans↗

Effect of local urokinase on arterial occlusion of lower limbs.

Sixty nine patients were treated with local intra-arterial urokinase (37,500 U/CTA. hr-1) for recent severe ischemia of lower limbs: 27 (40%) ultimately required amputation. The difference of amputation rate between the groups with and without thrombolysis was not significant (33% v. 42%). A biological study in 6 patients showed that local arterial plasminemia occurred in only 1 patient. Local urokinase does not strongly stimulate "endogenous" thrombolysis and enhances "exogenous" thrombolysis only very inconstantly. A better adaptation of urokinase dosage or the use of an agent with higher affinity for fibrin might improve the efficiency of local thrombolytic therapy.

Aged↗

Effects of in vitro and in vivo exposure to insulin upon glucose carbon accumulation in rat aorta: different patterns of response for intima-media and adventitia.

We have studied the effect of insulin upon the accumulation of glucose carbon into the intima-media and the adventitia of rat aorta following in vitro exposure by adding insulin to the incubation medium, and in vivo exposure by producing relative hyperinsulinemia during life and subsequently incubating excised tissue in a medium containing no insulin. Hyperinsulinemia in vivo was either (1) endogenous--following 1.5-2 hr of refeeding after a 48-hr fast--or (2) exogenous--following an i.v. injection of insulin. For adventitia, a significant stimulation was found after both in vitro (+ 53%, p < 0.001) and in vivo exposure to insulin (+ 96%, p < 0.01 with endogenous insulin; + 75%, p < 0.05 with a dosage of 2 U/kg of exogenous insulin). For intima-media, the stimulation was weak and insignificant after in vitro exposure (+ 11%, p > 0.30), but became important and significant after in vivo exposure to insulin (+ 100%, p < 0.001 with endogenous insulin; + 50%, p < 0.05 with a dosage of 0.5 U/kg and + 49%, p < 0.05 with a dosage of 2 U/kg of exogenous insulin). For the in vivo exposure experiments, we found a significant linear correlation (r = 0.611, p < 0.005) between plasma insulin concentrations and glucose carbon accumulations into intima-medias of control and refed rats. These results establish the insulin sensitivity of the adventitia and show a sensitivity of intima-media only to in vivo insulin exposure. These different behaviors of intima-media in vivo and in vitro may have a hemodynamic basis.

Animals↗

[Multiple recurrent paralysis of the cranial nerves (author's transl)].

The authors describe three patients presenting several episodes of paralysis of the motor and sensory cranial nerves and discuss possible aetiological factors. The paralytic attacks were regressive and were repeated at irregular intervals over a period of several years. It was confirmed that no local or general cause for the symptoms existed and the conclusion was reached that they were part of an autonomous clinical syndrome of unknown aetiology. Other cases have been reported in the published literature in which a non-specific inflammatory mechanism is suggested but no biological or pathological basis exists to support this physiopathological hypothesis. The clinical syndrome follows a benign course, the paralysis being regressive and the affection remaining confined to the peripheral nervous system of mesencephalic origin.

Aged↗

Hydrolase activities in the rat aorta. I. Effects of diabetes mellitus and insulin treatment.

Vascular disease in diabetics could arise in part from altered vessel wall catebolism. Specific activities of hydrolases in aortic smooth muscle cells from rats with streptozotocin-induced diabetes were measured. Enyzmes included: neutral alpha-glucosidase, alpha-mannosidase, and lysosomal N-acetyl beta-glucosaminidase, beta-galactosidase, cathepsin C, acid alpha-glucosidase, and acid cholesteryl esterase. After 4,8, and 11 weeks of diabetes, activities of all enzymes studied were decreased significantly in diabetic vessels, decreases ranging from 15% for cathepsin C to 62% for alpha-mannosidase. After 3 weeks of diabetes, insulin treatment for 1 week restored enzyme levels to normal. After 7 weeks of diabetes, 1 week of insulin treatment did not restore enzyme levels fully to normal (acid cholesteryl esterase was unchanged); 4 weeks of insulin did. Acid phosphatase and N-acetyl beta-glucosaminidase activities were reduced markedly in histochemical studies of diabetic aortas at all time periods and were restored by insulin treatment. Alloxan-induced diabetes gave results similar to those with streptozotocin. Significant decreases of aortic hydrolase activities, including those of lysosomes, occur in experimental diabetes mellitus and could contribute to accumulation of substrates in vascular smooth muscle cells.

Alloxan↗