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Biomedical subjects

A Fournier

Publications and source records attributed to A Fournier.

At least 487 records · Page 27Linked to original sources
PubMed1987

[Cardionatrin, a cardiac hormone].

The demonstration by De Bold, in 1981, that atrial extracts are able to produce a dramatic hypotensive and natriuretic effect led, within 5 years, to the identification and biosynthesis by genetic biotechnology of a new hormone: the atrial natriuretic polypeptidic factor or cardionatrin which is stored in the atrial granules previously described by Kisch. The secretion of this hormone is stimulated by distension of both right and left atria, and this explains why it plays a key role in cardiovascular homeostasis. Cardionatrin acts mainly as an antagonist of two pressive systems: the renin-angiotensin-aldosterone system and the adrenergic system. It acts by stimulating receptors which induce an increase of cyclic guanosine monophosphate and a decrease of cyclic adenosine monophosphate. Its natriuretic effect is explained not only by an increase in glomerular filtration rate but also by an increased secretion of papillar interstitial fluid into the collecting ducts.

Arrhythmias, Cardiac↗
PubMed1987

Effect of pregnancy on plasma renin activity and glomerular synthesis of prostaglandins and thromboxane in rats.

Normal pregnancy in women and rats is characterized by an increased glomerular filtration rate. Because prostaglandin glomerular synthesis has been reported to be increased in 2 other circumstances with glomerular hyperfiltration (streptozotocin-induced diabetes and high protein dietary intake in Heymann nephrilis), we studied prostaglandin biosynthesis in glomeruli obtained from pregnant Wistar rats in comparison with non pregnant rats during the estrus cycle. Comparatively to the 3 first phases of the cycle, and wether or not arachidonic acid was present, PGE2 and PGF2 alpha production rates were found significantly higher in diestrus 2 (2-3 fold increase for both) at 15 days of pregnancy (2 fold increase for PGE2, 5-6 fold increase for PGF2 alpha) and at 21 days of pregnancy (5-6 fold increase for both). On the other hand synthesis of TXB2 was not increased during pregnancy nor during diestrus 2. Plasma renin activity (PRA) was increased during pregnancy. It is concluded that in presence of increased PRA, the increased synthesis of PGE2 may be the hormonal factor explaining, at least in part, the hemodynamic mechanism of glomerular hyperfiltration which has been previously described by micropuncture techniques and characterized by increased renal plasma flow, increased glomerular filtration pressure and decreased ultrafiltration coefficient.

Animals↗
PubMed1987

Bicarbonate haemodialysis: an adequate treatment for lactic acidosis in diabetics treated by metformin.

Lactic acidosis in diabetics on metformin therapy is rare but still associated with poor prognosis. The authors report here five cases. Three patients were initially with a cardiovascular collapse and all had an acute renal failure. Sodium bicarbonate haemodialysis therapy led to a dramatic improvement. Consciousness and hemodynamic status recovered rapidly. Severe metabolic and blood gases derangements were also rapidly corrected. Plasma metformin removal, appreciated by repeated blood samplings in 3 cases, was satisfactory. All patients survived. However, blood metformin levels remained abnormally high at the end of the dialytic therapy. In conclusion, (1) bicarbonate dialysis is an adequate treatment of lactic acidosis observed in diabetic patients treated with metformin since it rapidly corrects the acid-base disorders and partially removes metformin; (2) the sole accumulation of metformin is not sufficient to explain lactic acidosis since this latter might be corrected in spite of persisting high levels of blood metformin.

Acidosis, Lactic↗
PubMed1987

Prostanoid synthesis by isolated rat glomeruli: effect of oestrous cycle and pregnancy.

1. An increase in glomerular prostaglandin (PG) synthesis has been reported in two experimental models of increased glomerular filtration rate (GFR). 2. Because pregnancy, in women and rats, is also associated with an increased GFR, we studied PG biosynthesis by glomeruli isolated from pregnant rats in comparison with virgin rats at the different phases of the oestrous cycle. 3. PGE2 and PGF2 alpha synthesis markedly increased during pregnancy (at day 21 of gestation a five- to sevenfold increase of PGE2 and PGF2 alpha was seen; at day 15 of gestation a threefold increase of PGE2 and a sixfold increase of PGF2 alpha was noted). However, thromboxane A2 (TXA2) synthesis was similar in all the groups studied. 4. Among the four phases of the oestrous cycle, dioestrus was characterized by a significant increase in glomerular synthesis of PGE2. 5. The fact that during pregnancy the increase in the vasodilator PGE2 is not counteracted by an increase in the constrictor TXA2 must be taken into account when explaining the glomerular hyperfiltration which characterizes the pregnant state. 6. The increase of PGE2 synthesis during dioestrus should be considered in studies of PG synthesis using virgin rats as controls.

Animals↗
PubMed1987

[Acute renal insufficiency caused by observed a combination of enalapril, furosemide and flurbiprofen in a patient with retroperitoneal fibrosis].

The case of vasomotor parenchymal acute renal failure is reported in a patient a few days after the initiation of treatment by Enalapril which is a new converting enzyme inhibitor. No renal artery stenosis could be demonstrated, which is in contrast with the numerous cases reported up to now. However the helping roles of an incomplete obstruction by a peri-aneurysmal retroperitoneal sclerosis, of prolonged anterior treatment with flurbiprofen and of simultaneous administration of furosemide may be discussed.

Acute Kidney Injury↗
PubMed1987

[Anticoagulation in hemodialysis sessions with a low molecular weight heparin (CY 222, Choay). Dosage studies in chronic hemodialysis. Its use in patients at high risk of hemorrhage].

Efficacy of CY 222 for providing anticoagulation during hemodialysis was evaluated in three successive trials by rating quality of blood restitution (degree of coagulum formation in extracorporeal circulation) and by assay of fibrinopeptide A. Its safety was assessed by measurement of manual compression time necessary to ensure hemostasis of puncture points at end of session. Details of the first preliminary study were: 60 sessions in 11 chronic uremia patients; CY 222: 75, 150 and 300 A-Xa IC U/kg + 1,000 A-Xa IC U/h, then 150 and 300 A-Xa IC U/kg without continuous injection, compared with standard heparin (SH) at the usual dosage for each patient (60 +/- 13 IU/kg). Results showed CY 222 at 150 U/kg + 1,000 U/h to possess the same efficacy as SH and to give a shorter compression test time: for 150 U/kg the efficacy was satisfactory, although less than with SH, and compression times were shorter (interest in patients at risk of hemorrhage). For 300 U/kg, efficacy was superior (improved restitution and lower FPA level at end of seance: 6 ng/ml instead of 15 ng/ml.p less than 0.002) and compression times were identical. The second study to evaluate optimal dosage of CY 222 in chronic hemodialysis (CHD) involved: 10 patients; CY 222: 200 A-Xa IC U/kg and 250 A-Xa IC U/kg by single-dose injection. Results failed to demonstrate any significant difference in evolution of FPA levels, but restitution was better at 250 U/kg. In addition, investigation of the effect of rinsing of ECC with standard heparin before the session showed that its suppression did not alter effectiveness but improved tolerance.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation↗
PubMed1987

[Pregnancy-induced hypertension and pre-eclampsia develop in spite of high circulating levels of cardionatrin].

Plasma cardionatrine was measured during pregnancy in 14 normotensive non pregnant women, 15 normotensive pregnant women, 35 pregnancy induced hypertension (PIH) and 10 preeclampsia (PE) and again 2 months after delivery in respectively 7, 15 and 7 cases together with plasma volume, PRA and plasma aldosterone. The plasma levels of cardionatrine are higher in pregnant normotensive women than in non pregnant normotensive women suggesting that pregnancy per se stimulates cardionatrine secretion. The higher levels of cardionatrine in PIH and specially in PE during pregnancy and the greater decrease of plasma cardionatrine after delivery in the hypertensive patients than in the normotensive controls exclude a deficiency of cardionatrine secretion in the pathogenesis of hypertension. These data rather suggest a compensatory role of cardionatrine in the prevention of blood pressure increase. Plasma volume was decreased in PIH (-17 p. 100) and in preeclampsia (-25 p. 100). The simultaneous high levels of cardionatrin may explain the inappropriate stimulation of the renin and aldosterone secretion in these hypovolemic hypertensive states.

Adult↗
PubMed1987

[Digoxin-like natriuretic factor, raised during normal pregnancy, is increased in pregnancy-induced hypertension and pre-eclampsia].

UNLABELLED: The increase of peripheral resistance in pregnancy induced hypertension (PIH) and in preeclampsia (PE) is not yet explained since previous studies have found that renin-angiotensin-aldosterone system is actually depressed, that adrenergic system is inconstantly stimulated and that vasodilating prostaglandins are inconstantly decreased. In order to get a better insight in the pathogenesis of PIH and PE, we have measured the 24 h urinary excretion of digoxin-like natriuretic factor (DLF) in 15 normotensive pregnant women (NP), in 29 women with PIH and in 6 women with PE under normal salt diet, without treatment. DLF have been measured by radio receptor binding assay. Normal values were established in 14 normotensive non pregnant (NNP). In NP, 24 h urinary excretion of DLF was significantly higher than in NNP (respectively 14.9 +/- 7.5 and 9.5 +/- 2.5 nmol/mmol of creatininuria, p less than 0.01). Comparatively to NP, 24 h urinary excretion of DLF was significantly higher in PIH (31.7 +/- 19 nmol/mmol of creatininuria) and in PE (40.7 +/- 16.3 nmol/mmol of creatininuria). In PIH and PE, there were simultaneously a decrease of plasma renin activity and plasma volume but no difference for plasma catecholamines. IN CONCLUSION: 1. the production of DLF is increased by normal pregnancy; 2. it is increased in PIH and PE in comparison with NP and may explain the increase of peripheral resistance.

Adult↗
PubMed1987

Plasma bone Gla-protein: assessment of its clinical value as an index of bone formation in hemodialyzed patients.

Plasma bone-Gla protein was measured in 27 non-selected patients on chronic hemodialysis or hemofiltration with no overt radiological bone disease. Individual values ranged from normal to 10-times the upper limit of the normal range. Plasma bone-Gla protein correlated with the histomorphometric parameters of bone turnover and bone formation and with plasma parathyroïd hormone and alkaline phosphatase. When patients were classified according to their Bone Formation Rate, plasma bone-Gla-protein allowed a better distinction between high and low bone formation rates than did alkaline phosphatase or plasma parathyroïd hormone.

Adult↗
PubMed1987

[Response to influenza vaccine in uremic patients: relation to erythrocyte magnesium and the value of a second injection].

Humoral response to influenza vaccination being variable in uremic patients and being negatively correlated to red blood cell magnesium (RBC Mg) in non-uremic subjects, RBC Mg as well as plasma concentration of Mg were measured simultaneously with the antibodies titers after 1 and 2 injections of influenza vaccine in 21 non-uremic subjects and 47 patients on chronic hemodialysis. The RBC Mg and plasma Mg (MgP) were significantly higher in the dialysed patients (74 +/- 12 mg/l; 25 +/- 8 mg/l) than in the non-uremic subjects (54 +/- 5 mg/l; 19.4 +/- 1.5 mg/l). Furthermore, in the uremics RBC Mg was correlated to PMg whereas such a correlation was absent in the non-uremic patients. The humoral response of the uremic patients is depressed and becomes comparable to that of the non-uremic subjects after 1 injection only after 2 injections. In the uremic patients, the depressed humoral response is associated with higher RBC Mg (greater than 70 mg/l). The humoral response to influenza vaccine is depressed in uremic patients who have either the HBs antigen or no response to the hepatitis B vaccine but no link has been found between this immune status against the hepatitis B and RBC Mg. In conclusion, the humoral response of the uremic patients to influenza vaccine is depressed so that a second injection is necessary to give them sufficient protection.

Adult↗
PubMed1987

[Evaluation of maximal filtration capacity and renal functional reserve by an oral protein-loading test in adults and children].

After a protein load, the glomerular filtration increases to a maximum called maximal filtration capacity (MFC). The difference of this value with that observed in the fasting state defines the functional renal reserve (FRR). Fifty oral protein loads have been performed in 16 controls (13 adults and 3 children) and 31 patients with kidney disease or hypertension (22 adults, 9 children, 3 tests being performed twice). The load consisted in the adults of 80 g of various proteins. In the children the load consisted in the 100% of the protein intake recommended of the whole day. The urinary samples were made hourly during the 5 hours following the beginning of the meal. The MFC was not always observed during the 2 hours following the end of the meal. However the mean of the clearances measured during these 2 hours allowed an acceptable evaluation of the FRR in 42 out of 50 cases and had the advantage to reduce the errors linked to incomplete bladder voiding. In the adult controls the mean of hourly determined MFC is 156 +/- 27 ml/min, the mean of the clearances measured on the 2 hours following the meal is 136 +/- 21 ml/min and the fasting clearance 96 +/- 22 ml/min. The FRR is null in all patients with a nephropathy with a fasting clearance below 40 ml/min. It is modest or null in patients with acquired or congenital solitary kidney. Three out of five patients with proteinuria have MFC and FRR higher than the mean of the patients with comparable fasting clearances but without proteinuria suggesting that proteinuria is associated with a hyperfiltration state.

Administration, Oral↗
PubMed1986

The isolation of human beta-interferon receptor by wheat germ lectin affinity and immunosorbent column chromatographies.

Radioiodinated human beta-interferon-Ser 17 (Betaseron) was reversibly cross-linked to Daudi cells by dithiobis(succinimidylpropionate). The radioactive ligand was cross-linked to three macromolecules forming labeled complexes of apparent Mr values of 130,000, 220,000, and 320,000. Betaseron, human alpha-interferon, human interleukin 2 but not recombinant human gamma-interferon competed with the labeled ligand for binding to these putative receptor(s). Human leukocyte-produced gamma-interferon competed weakly with 125I-Betaseron for binding to Daudi cells. The Betaseron-receptor complex(es) was purified by passage through a wheat germ lectin column followed by chromatography on an anti-interferon immunosorbent column and semipreparative gel electrophoresis. The cross-linked ligand-receptor complex was shown to be highly purified by sodium dodecyl sulfate and acetic acid:urea:Triton X-100 polyacrylamide gel electrophoresis. It can be dissociated into the labeled Betaseron (Mr = 17,000) ligand and a receptor moiety which has an apparent molecular weight of 110,000. The chromatographic behavior of the ligand-receptor complex on wheat germ lectin column suggests that the receptor is a glycoprotein. The described procedure yielded about 1 microgram of Betaseron receptor from 10(10) Daudi cells, estimated to contain a maximum of about 15 micrograms of the receptor.

Binding, Competitive↗
PubMed1986

Electrophysiologic cardiac function before and after surgery in children with atrioventricular canal.

Thirty-two children with atrioventricular (AV) canal underwent electrophysiologic studies: 18 underwent preoperative studies at a median age of 3 years (range 6 months to 16 years); 14 underwent postoperative studies at a median age of 4 years (range 2 to 19); and 2 underwent both preoperative and postoperative matched studies. In the preoperative group the following abnormalities were observed: first-degree AV block in 5 patients (due to internodal conduction delay in 1, AV nodal conduction delay in 2 and normal intracardiac intervals in 2); internodal conduction delay but normal PR interval in 4; and disease of the sinus node in only 1. In the postoperative group the following abnormalities were observed: first-degree AV block in 9 (due to AV nodal conduction delay in 2, His-Purkinje system conduction delay in 1, upper normal intracardiac intervals in 3 and unidentified in 3); prolongation of the right ventricular apical activation time in 11 of 13 with right bundle branch block; abnormal sinus node function in 3; and abnormal AV nodal function in 4 (1 of whom had associated sinus node disease). Atrial and ventricular functions were normal in all preoperative and postoperative patients. Electrophysiologic dysfunction is rare in preoperative patients with AV canal; in postoperative patients electrophysiologic abnormalities occur in 38% and involve the sinus and AV nodes in 19 and 25%, respectively.

Adolescent↗