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D Moreau

Publications and source records attributed to D Moreau.

At least 91 records · Page 5Linked to original sources

[Effects of the level of polyunsaturated fatty acids of the diet on the functioning and depletion of energy substrates in the rat heart during perfusion by left atrial route].

The effects of semi-liquid diets containing 6.6% in weight of refined sunflower seed oil (SSO) or hydrogenated coconut oil (HCO) on cardiac endogenous substrates and functional parameters of rats hearts were compared to a standard laboratory chow during seven days. No difference appeared for cardiac glycogen and lipid constituents. Cardiac performance, measured through left atrial perfusion was enhanced by SSO diet and HCO one altered it. A significative phospholipid depletion appeared during the 45 minutes perfusion only in the HCO group.

Animals↗

[Evaluation of dietary vitamin intake in Burgundy (France)].

The daily intake of vitamin B1, B2, B6, PP, C, A, D and E was investigated in 297 adult subjects, undergoing a check-up examination in a Health Center in Burgundy, by the 7-day self-recorded prospective protocol, to determine the prevalence of vitamin deficiency risks in an area of a West European Country. The daily vitamin intake was lower than the French Recommended Dietary Allowances: RDA (CNERNA, 1981). The intake was between 50 and 80% of RDA for vitamin B1 in 58%, B2 in 24%, B6 in 59%, PP in 43%, C in 21%, A in 8%, D in 0.6%, E in 53% of the female population and for B1 in 40%, B2 in 18.5%, B6 in 59%, PP in 46%, C in 27%, A in 11%, D in 7% and E in 47% of the male population. The daily vitamin intake was less than half of RDA vor vitamin B1 in 11%, B2 in 0.6%, B6 in 33%, PP in 6.3%, C in 4.5%, A in 0.6%, D in 98%, E in 36% in the females and for B1 in 3%, B6 in 8.5%, PP in 3.5%, C in 5%, A in 0.7%, D in 91% and E in 9% in the males. The use of a probability analysis for estimating vitamin deficiencies showed intakes below their own requirement in 37.8% for B1, 18% for B2, 58.6% for B6, 46% for PP, 29% for C, 8.3% for A, 98% for D and 43.4% for E in the males and 62.5% for B1, 20.9% for B2, 86% for B6, 46% for PP, 24% for C, 9.2% for A, 98% for D and 59.7% for E in the females. Significant correlations were found between the daily vitamin intake and the caloric intake for B1 (r = 0.64), B2 (r = 0.46), B6 (r = 0.64) and PP (r = 0.62). The significantly lower caloric intake in females than in males explains a higher proportion of vitamin deficiencies for B1, B2, B6 and PP in this population. The consumption of green vegetables and fresh fruit, and, consequently, vitamin C intake, was higher in females. Although it was not possible to determine to what extent the vitamin intake deficiency contributes to an impaired biochemical vitamin status, the dietary data of this study supply sufficient information to demonstrate high prevalences of deficient vitamin status in France, particularly for B1, B6 and E.

Adult↗

Frequency of gastroesophageal reflux in neonates as assessed by 24-hour pH monitoring.

The purpose of the present study was to determine the frequency and the other characteristics of gastroesophageal reflux (GER) in 46 asymptomatic neonates during the first weeks of life. The GER were assessed by 24-hour continuous esophageal pH monitoring (CPR). The frequency of all the GER was 0.66 +/- 0.54/h (0 to 2.21). Half of the GER were determined as acid (pH less than 4 during at least 15 sec), 23% as highly acid (pH less than 3 during at least 15 sec), 39% as weakly acid (abrupt fall of the pH higher than 1 unit pH), and 11% as non acid (abrupt increase of pH higher than 1 unit pH). According to these results, a CPR should be considered as pathologic in neonates when the following criteria are fulfilled (upper limits fixed at means + 2 S.D.): 1. frequency of acid GER longer than 5 min above 0.35/h; 2. time ratio at pH below 4 exceeding 10.4%; or 3. frequency of very acid GER greater than 0.53/h.

Age Factors↗

Effect of alpha-adrenoceptor antagonists (phentolamine, nicergoline and prazosin) on reperfusion arrhythmias and noradrenaline release in perfused rat heart.

Rat isolated hearts were perfused through the left atrium with a modified Krebs-Henseleit solution or mounted on a Langendorff perfusion system. The hearts were prelabelled with [3H]-noradrenaline [( 3H]-NA) and the left main coronary artery was ligated for 10 min after which reperfusion followed. The liberation of [3H]-NA and the development of ventricular tachycardia and fibrillation were monitored throughout. During the occlusion period, ventricular arrhythmias did not occur and heart rate was not significantly altered in the control series. In contrast, reperfusion was followed by ventricular fibrillation and ventricular tachycardia in all the hearts in the control series (Langendorff or 'working' models). The alpha-adrenoceptor antagonists phentolamine (7.1 X 10(-6) M and 7.1 X 10(-5) M) and nicergoline (3.1 X 10(-6) M) diminished or prevented reperfusion arrhythmias. However, prazosin (5.2 X 10(-6) M) was not effective. The lower concentration of phentolamine did not alter the pattern of [3H]-NA release, whereas, high doses of phentolamine and nicergoline increased the release of [3H]-NA. Prazosin (5.2 X 10(-6) M) caused a very marked increase in release of [3H]-NA but was not antiarrhythmic. A 'membrane-stabilizing' effect seems the most appropriate explanation for these antiarrhythmic effects of alpha-antagonist agents.

Adrenergic alpha-Antagonists↗

Evaluation of sympathoadrenal activity, adrenocortical function and androgenic status in five men during a Himalayan mountaineering expedition (ascent of Mt Pabil, 7,102 m, 23,294 ft).

Sympathoadrenal activity, adrenocortical function and androgenic status were studied in five well-trained mountaineers during the different phases of a mountaineering expedition during the ascent of Mt Pabil (7,102 m) in the Ganesh Himal massif. Sympathoadrenal activity was evaluated by measuring urinary excretion of adrenaline, noradrenaline, metanephrines, and vanillinmandelic acid. Adrenocortical function was assessed by measuring urinary excretion of free cortisol, 17 OHCS (17-hydroxycorticosteroids) and androgenic status by measuring testosterone glucuronide, Adiol (5 alpha-androstane-3 alpha, 17 beta diol) and 17KS (17-ketosteroids). Reference values were obtained at Chamonix at 1,037 m during rest. During trekking noradrenaline increased significantly while Adiol and 17-KS decreased. The fall in the urinary androgenic pool persisted during the next phases of the expedition. At base camp (4,800 m) noradrenaline, its metabolites and free cortisol increased mainly during physical activity. Above 6,000 m, adrenaline, noradrenaline, their metabolites, free cortisol and 17-OHCS reached a maximum value. During the return to sea level, the urinary level of these parameters was still high. The drop in the urinary androgenic pool observed during trekking and exposure to high altitude confirms results obtained in other studies on prolonged efforts. This hypoandrogenicity may play an important role in the metabolic adaptations as well as in the mental state of the climbers. The increase of sympathoadrenal activity and of adrenocortical function may be considered as a regulatory element in the adaptative response to hypoxia and other stressors proper to high altitude.

17-Hydroxycorticosteroids↗

Role of beta-adrenoreceptor antagonism in the prevention of reperfusion ventricular arrhythmias: effects of acebutolol, atenolol, and d-propranolol on isolated working rat hearts subject to myocardial ischemia and reperfusion.

The role of catecholamines in the genesis of ventricular arrhythmias during the reperfusion period following coronary occlusion remains incompletely understood. An isolated rat heart preparation, free from the influence of autonomic innervation or of circulating catecholamines, was used to assess the effects of beta-adrenoceptor blockade. The hearts were prelabeled with tritiated norepinephrine ( NE3H ), and the total radioactivity and that in NE3H were measured in the effluent coronary flow. The left main coronary artery was ligated for 10 minutes after which reperfusion followed. The liberation of NE3H and the development of ventricular tachycardia and fibrillation were monitored throughout. The cardioselective beta-antagonist agent, acebutolol, in a high concentration (1.1 X 10(-4)M), had good beta-antagonist effect in response to the added isoproterenol (10(-6)M); this concentration of acebutolol also suppressed sustained reperfusion ventricular arrhythmias but unexpectedly increased the release of NE3H . Atenolol, another cardioselective agent, did not prevent reperfusion ventricular arrhythmias even in a high concentration of 40 mg/L (1.5 X 10(-4)M). The d-isomer of propranolol, with poorer beta-antagonist properties than the l-isomer, prevented such ventricular arrhythmias in a concentration of 1.3 X 10(-5)M, which was low when compared to that of atenolol. It is proposed that the beta-antagonist activity of the compounds tested could not explain the inhibition of reperfusion ventricular arrhythmias and that another quality such as membrane-stabilizing activity may be involved.

Acebutolol↗

Evaluation of pyridoxine intake and pyridoxine status among aged institutionalised people.

The vitamin B6 status of 60 institutionalised elderly subjects (group A: 31 men, mean age = 77 yr and 29 women, mean age = 84 yr) and 41 healthy young adults (group B or control group: 18 men, mean age = 30 yr and 23 women, mean age = 27 yr) was evaluated using erythrocyte aspartate aminotransferase activity coefficient (alpha EGOT) and plasma pyridoxal phosphate (PLP) level (vitamin B6-deficient subjects = alpha greater than 2.0 and PLP less than 80 nmol/l). The kilocalorie, protein and pyridoxine intakes were also estimated. Regarding calories and protein, the diets may be generally considered satisfactory in respect to the French 1981 RDA. The mean dietary intake of vitamin B6 was less than 2 mg/day in all groups. Ninety per cent of the aged, 80 per cent of females in group B in contrast to 56 per cent of males in group B consumed less than their individual vitamin B6 requirements as determined by a probability method. As the incidence of vitamin B6 biochemical deficiency was much higher in the group A (71% for males and 86% for females) than in the control group (11% for males and 30% for females), it is concluded that the high incidence of biochemical vitamin B6 deficiency noted in the aged appeared more relevant from an altered metabolism of the vitamin than from a too low energy intake. Supplements with high doses of vitamin B6 to aged subjects caused a significant decrease in alpha EGOT and a significant increase in PLP levels.

Adult↗

[Sodium nitroprusside and coronary surgery].

The anti-hypertensive properties of sodium nitroprusside have been tested in 20 patients undergoing coronary arterial surgery. Were measured the arterial pressure, heart rate, mean right atrial pressure and mean left atrial pressure. The cardiac output, systemic vascular resistance and left ventricular stroke work index were deduced. A dose of 0.8 to 3 micrograms . kg-1 . min-1 sodium nitroprusside was given at the start of surgery, and immediately afterwards. The results showed a decrease of the systemic vascular resistance, a significant drop of arterial pressure, and a significant increase of heart rate as well as a tendency for the cardiac output to fall, probably because of insufficient vascular filing. When the mean left atrial pressure was kept at 14.8 +/- 3 mmHg (1.97 +/- 0.40 kPa), and left ventricular stroke work index fell, whilst cardiac output increased. Sodium nitroprusside seemed to be useful in coronary arterial surgery if used with care.

Adult↗

Comparison of retinol-binding protein and beta 2-microglobulin determination in urine for the early detection of tubular proteinuria.

The specificity, sensitivity and stability of beta 2-microglobulin (beta 2-m) and retinol-binding protein (RBP) in urine as indices of tubular proteinuria were compared. In vitro experiments show that RBP in urine is stable down to pH 4.5, whereas beta 2-m degrades below pH 5.5. This was confirmed by the relationships between pH and the concentration of both proteins in the urines from 150 healthy subjects. Urinary RBP was independent of pH (r = 0.125) but in contrast at pH below 6, beta 2-m concentration was inversely correlated with pH (r = 0.54, p less than 0.05). The comparison of urinary excretion of RBP and beta 2-m in 68 patients with renal diseases shows that in absence of a pH effect, the sensitivity and specificity of both proteins as indices of tubular proteinuria are rather similar. Therefore, in view of its greater stability in urine, RBP appears to be a more practical and reliable index of proximal tubular function than beta 2-m.

Adult↗

Latex immunoassay of retinol-binding protein.

Latex immunoassay, a sensitive method based on latex particle agglutination, is used here for the determination of retinol-binding protein in human biological fluids. The assay, similar to that described previously for beta 2-microglobulin (Clin. Chem. 27:832-837, 1981), consists of incubating the sample at 37 degrees C for 30 min with antibody-coated particles, then quantifying the resulting agglutination by particle-counting or turbidimetry. Latex particles coated with antibody are stabilized just before use by dispersing them in a solution of bovine serum albumin at pH 10. The standard curve ranges from 0.5 to 32 micrograms/L; recovery averages 102% in urine and 93.5% in serum; between- and within-assay CVs range from 5.1 to 11.7%. The correlation coefficients of latex immunoassay with rocket immunoelectrophoresis for analysis of retinol-binding protein in 26 urines and with radial immunodiffusion in 30 sera are 0.99 and 0.91, respectively. In healthy subjects, the mean urinary excretion of retinol-binding protein is 52.5 micrograms/g of creatinine (SD = 59.2 micrograms/g of creatinine; n = 150) and the concentration in serum averages 46 mg/L (SD = 10.4 mg/L, n = 22).

Beta-Globulins↗

Effect of substrate on release of myocardial norepinephrine and ventricular arrhythmias following reperfusion of the ischemic isolated working rat heart.

Isolated rat hearts were prelabeled with 3H-norepinephrine (NE), submitted to coronary artery ligation, and perfused through the left atrium with a modified Krebs-Henseleit solution containing 3 mM potassium and four different substrates: 5.5 mM glucose, 5.5 mM glucose plus 0.15 or 0.5 mM palmitate bound to albumin in a molar ratio of 6:1, and 11 mM glucose. The coronary artery ligature was removed after 30 min of perfusion of the ischemic working heart. With all substrates the release of radioactivity in the coronary effluent remained relatively constant during the ischemic period. Reperfusion was associated with a sudden release of radioactivity and of 3H-NE, but the intensity of the efflux was influenced by the nature of the perfusion substrate. The highest release was observed with 5.5 mM glucose and the lowest release in the presence of 0.15 mM palmitate. Intermediate and similar releases were seen with the two other substrates. On reperfusion of the ischemic heart, ventricular arrhythmias (tachycardia and fibrillation) were very marked with 5.5 mM glucose and in the presence of 0.5 mM palmitate. They were significantly delayed in the presence of 0.15 mM palmitate and almost absent with 11 mM glucose. These results do not show a relationship between the amount of NE liberated during the post-ischemic period and the extent of ventricular reperfusion arrhythmias. We conclude that either myocardial NE is not implicated in the genesis of reperfusion arrhythmias or that cardiac vulnerability to the arrhythmogenic effect of NE is influenced by the metabolic state of the myocardium, which is dependent on the nature of the perfusion substrate.

Animals↗