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H Favre

Publications and source records attributed to H Favre.

At least 73 records · Page 4Linked to original sources
PubMed1989

[Sequential study of the plasmatic atrial natriuretic factor and the urinary excretion of an ouabain displacing factor and of dopamine in normotensive pregnant women before and after labor].

Estimation of urinary excretion of a ouabain displacing factor (ODF) and dopamine was carried out immediately before delivery, 7 days and 70-90 days after delivery in 12 normotensive pregnant women. Simultaneous estimation of plasma 99-126 atrial natriuretic factor (ANF), plasma renin activity (PRA) and plasma aldosterone were also undertaken. The data were compared with those obtained in a non pregnant normotensive group of women (n = 14) and a group of pregnant normotensive women in the early third trimester (n = 14). Urinary ODF and dopamine were significantly higher in the early third trimester when compared with non pregnant women but immediately before delivery, ODF excretion had fallen below non pregnant values and dopamine excretion had dropped to control values. Both remained low after delivery. Plasma ANF was higher in pregnant women when compared with non pregnant controls and remained high just before delivery and 7 and 70-90 days after delivery. PRA and plasma aldosterone were higher during pregnancy and had fallen to non pregnant values 7 days post-partum. It is concluded that there is considerable discrepancy in the evolution of natriuretic and antinatriuretic factors before and after delivery and that the drop of PRA and aldosterone by 7 days post-partum, contrasting with the unchanged high values of ANF, may contribute to negative sodium balance after delivery.

Adult↗
PubMed1987

Combined steroid-cyclosporin treatment of chronic autoimmune diseases. Clinical results and assessment of nephrotoxicity by renal biopsy.

Twenty-one patients suffering from different autoimmune diseases (14 from systemic lupus erythematosus, 4 from rheumatoid arthritis, one from Sjögren's syndrome, one from systemic hypersensitivity vasculitis, and one from diffuse proliferative glomerulonephritis) were treated with a combined immuno-suppressive regimen. Cyclosporin was given at a dose of 5 mg/kg/day together with steroids. In addition, the rheumatoid arthritis patients also received methotrexate. In all patients a kidney biopsy was performed after a treatment period of 17 to 42 months (mean duration 21.7 months). The cumulative cyclosporin dose at the time of biopsy varied from 1.071 to 4.587 mg/kg. Patients suffering from systemic lupus erythematosus and rheumatoid arthritis were assessed according to a scoring system set up for this purpose. The combined therapy proved useful in these patients as reflected in the diminution of the respective activity scores, improvement of kidney function, and diminution of proteinuria. Histological examination of the kidney biopsy specimens showed only minimal activity in patients with systemic lupus erythematosus. No unequivocal signs of renal toxicity could be detected. In the last group, the condition of the patient with Sjögren's syndrome was stabilized and the patient with systemic vasculitis improved clinically. Neither patient had signs of kidney lesions. The patient with diffuse proliferative glomerulonephritis, in whom kidney biopsy was performed before and after treatment, showed improvement of kidney function, diminution of proteinuria, and diminution of inflammatory activity within the kidney, and no signs of cyclosporin toxicity.

Adolescent↗
PubMed1987

A receptor binding assay for endoxin in human urine.

Endoxin is an endogenous substance known to participate in the regulation of the sodium balance and hypertension. Its chemical nature remains elusive. Based on its capacity to specifically bind to Na-K ATPase receptors we describe a receptor assay for its measurement in human urine. The endoxin was extracted by methanol and desalted on a silicagel column with a mixture of chloroform-ethanol. Calibration curves have been established by the transformation of the weight of crude extract in actual content of active material expressed in nmol/l as calculated from Scatchard plots analysis. Normal values are given for subjects on regular salt diet. Changes in endoxin urinary elimination after an oral salt load are outlined.

Binding, Competitive↗
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

Receptor-assay for endogenous inhibitors of Na-K ATPase.

It is now accepted that there is an endogenous digitalis-like substance (EDLS), previously called natriuretic factor, present in different mammalian species which participates to the regulation of the sodium balance and at least in some situations, to the genesis of hypertension. The physiological and pathophysiological role of this substance is well recognized. However, its chemical nature remains elusive. Our purpose was to define a receptor assay for this EDLS in order to be able to measure its concentration in urine and blood. To do so, we first prepared a pool of lyophylised urine from salt loaded men. The active material was isolated by Sephadex G25 chromatography. Using the same active fraction, we investigated its biological effects. Series of experiments have demonstrated the various properties of the EDLS: inducing natriuresis when injected into a rat, diminishing short circuit current in toad's bladder and colonic mucosa of rat in in vitro preparations, inhibiting Na-K ATPase activity in isolated toad's bladder cells, binding to ouabain receptors and cross-reacting with different antibodies directed against digoxin. Among these properties, the binding to ouabain receptors offers the unique opportunity to progress in our knowledges of the substance, making possible the calculation of its constant of affinity and the estimation of the molality of the active material contained in a gram of crude extract. Knowing the constant of affinity of the EDLS for its receptor would provide the best identification of the substance as long as we do not know its exact chemical nature.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Comparative effects of ouabain, natriuretic factor and ammonium chloride in the toad urinary bladder.

Electrical changes and direct effects on Na-K ATPase activity induced by an endogenous digitalis-like natriuretic factor (NF), NH4Cl and ouabain were studied in toad bladders. NF inhibited the SCC and the Na-K ATPase activity in a similar manner to ouabain, but induced a greater increase in calculated direct current resistance (R) (p less than 0.05). NH4Cl was a weak inhibitor of Na-K ATPase activity, although it produced steeper SCC inhibition slopes than those observed with ouabain or NF (p less than 0.01). The data suggested the same mechanism of action of NF and ouabain on the sodium pump, with an additional effect of the former on apical sodium permeability of the cells and/or closure of paracellular routes leading to an increased tissue resistance. In contrast, the effects of NH4Cl were mostly compatible with intracellular inhibition of apical sodium entry into the cell.

Ammonium Chloride↗
PubMed1986

[Importance of the urinary index in the differential diagnosis of acute renal insufficiency].

The importance of the urinary indices for the diagnosis of acute renal failure is critically reviewed in the light of the literature and our own experience. To differentiate pre-renal from renal acute failure, urine/plasma creatinine ratio (65%) and fractional sodium excretion (99%) provide the best predictive values. Post-renal acute failure is diagnosed by radiological investigation. A theoretical model demonstrates why fractional sodium excretion has advantages on U/P creatinine ratio. The former parameter is independent of urinary volume and glomerular filtration rate, and thus it specifically indicates whether or not tubular function is altered. The U/P creatinine ratio depends on the urinary volume and on the glomerular filtration rate, and therefore this ratio is less specific. The only limitation on the use of fractional sodium excretion in the diagnosis of pre-renal versus renal acute failure appears in patients with an underlying disease able to modify sodium transport by the renal tubules.

Acute Kidney Injury↗
PubMed1986

Renal biopsy in SLE irrespective of clinical findings: long-term follow-up.

We analyzed data from 56 patients with Systemic Lupus Erythematosus (SLE) in whom renal biopsies were done systematically. The data taken into account for the study were: the histologic glomerular lesions at diagnosis, serum creatinine value, degree of proteinuria and qualitative urine sediment analysis at the time of biopsy, patient age at diagnosis and the evolution of renal function until the time the study was made. Therapy was prescribed according to the glomerular histologic lesion. The mean follow-up period from the time of the first biopsy was 8.2 years. At the time of the study, only 3 patients (5.3%) were on dialysis, while the rest of the patients (94.7%) had a satisfactory renal function. Our results indicate that systematic renal biopsy in SLE patients can furnish valuable data concerning the renal status whether there are clinical signs of renal involvement or not. Treatment based on the histologic images alone may considerably improve renal survival in SLE.

Adolescent↗
PubMed1985

[Evaluation of a method for determining the specific gravity of urine with a reagent strip].

The performance of a new reagent strip method for determining the urine specific gravity was evaluated. 342 clinical specimens were assayed in duplicate by the new method and by the "falling drop" technique. The reproducibility (two lots of strips, four operators) was very good (96.2 per cent agreement between replicates within a range of 0,0100 specific gravity units). The correlation with the comparative method was satisfactory [81,2 per cent concordance within a range of 0,0100 specific gravity units]. No interference was found from ketones, blood or urobilinogen. The influence of proteins and glucose is discussed. The practical advantages of the new method are described.

Acute Kidney Injury↗
PubMed1985

Filtration fraction: an index of renal disease activity in patients with systemic lupus erythematosus.

Renal plasma flow (RPF) and glomerular filtration rate (GFR) were estimated by 125I hippuran and 51Cr EDTA clearances using a single shot technique on two occasions at one-year intervals in 22 patients fulfilling the ARA criteria for systemic lupus erythematosus (SLE). All these patients had histologically proven renal disease. Filtration fraction was a better parameter than proteinuria, urinary sediment or GFR for recognising diffuse proliferative glomerulonephritis with a sensitivity of 61 per cent and a specificity of 88 per cent. After one year all the patients with an initially low filtration fraction (FF) had significantly changed their GFR, which demonstrates that this parameter indicates the presence of an active renal lesion.

Glomerular Filtration Rate↗
PubMed1985

Relationship of renal prostaglandins to distal transport of sodium chloride in normokalemic and hypokalemic man.

The relationship between renal prostaglandins (PG) and electrolyte transport in the thick ascending limb of Henle's loop (TALH) was examined in 8 normal subjects and in 7 patients with hypokalemia, the latter including 4 cases of Bartter's syndrome. Distal fractional delivery and distal reabsorption of chloride and sodium were determined using clearance techniques under maximal volume expansion, and urinary excretion rates of PGE2 and PGF2 alpha were measured. In the normal subjects, suppression of PG synthesis by indomethacin decreased distal delivery without changing distal reabsorption, suggesting that PG may influence solute transport at a site proximal to the diluting segment. In the subjects with Bartter's syndrome, however, distal reabsorption was impaired, this defect being apparently independent of PG as it was unaffected by inhibition of PG synthesis. In the patients with hypokalemia due to non-renal causes, distal reabsorption of chloride was increased, resulting in a decreased chloride clearance. These results suggest a link between renal PG and solute transport in normal man and also provide evidence that Bartter's syndrome is characterized by a prostaglandin-independent defect in distal reabsorption which is not found in hypokalemia due to other causes.

Absorption↗
PubMed1984

[How to treat hyperuricemia?].

Among a normal population, 21.5% of men have a blood level of uric acid above 6.8 mg%. Half of these subjects also present concomitant elevation of at least one other biological parameter. Clinically they differ from normo-uricemic subjects by weight, level of blood pressure and a trend to diabetes. From the recent literature it appears that hyperuricemia by itself does not constitute a risk factor as far as renal and vascular diseases are concerned. However, prevalence of gouty arthritis and urinary stones correlates with the blood uric acid level. Therefore, treatment of asymptomatic hyperuricemia must be avoided, and side effects of the drugs weighed. Acceptable indications for treatment are frequent attacks of urolithiasis or arthritis poorly tolerated by the patients.

Arthritis, Rheumatoid↗