PubMed Health⌕ Search

Biomedical subjects

P Desgrez

Publications and source records attributed to P Desgrez.

At least 19 recordsLinked to original sources
PubMed1985

[Calcium oxalate monohydrate (whewellite) renal lithiasis].

Pure calcium oxalate monohydrate lithiasis is rare--about 5 to 10% of total renal lithiases. The proportion is the same in men and women. Pure calcium oxalate stones are a polished dark brown color, and are very hard. They are visualized radiologically as regular and homogeneous. From a biological standpoint, this type of stone is frequently associated with normal calciuria and oxaluria. Pure calcium oxalate monohydrate stones rarely evolve.

Adult↗
PubMed1984

[Monohydrate and dihydrate oxalic lithiasis. Calculi, their macroscopic structure (radiographic and therapeutic impact). Calciuria and oxaluria].

Calculi of pure calcium oxalate monohydroxide are hard, polish, dark brown stones, of a very tenuous crystalline structure. On the contrary, calculi of pure bihydroxide oxalate are clear irregular stones with a spiky surface. They are more friable and less hard than monohydroxide oxalate stones. Monohydroxide oxalate stones radiologically are regular and homogeneous, whereas bihydroxide oxalate stones have an irregular aspect. Monohydroxide oxalic lithiasis is less frequent than bihydroxide oxalic lithiasis. The proportion of monohydroxide lithiasis is the same in men and women whereas bihydroxide lithiasis is more frequent in men. Of a biologic point of view, in monohydroxide lithiasis, calciuria and oxaluria are often normal while proportion of hypercalciuria and hyperoxaluria is more important in bihydroxide lithiasis. Evolutivity is clearly inferior in monohydroxide lithiasis than in bihydroxide lithiasis.

Adult↗
PubMed1983

[Oxaluria in urinary lithiasis].

The normal value of oxaluria, as determined by gasliquid chromatography, is about 30 mg/24 h. In most cases of renal stone formation (60-70%) the stones are composed of calcium oxalate alone or associated with calcium phosphate. The more evolutive the disease, the higher the oxaluria. The part played by oxaluria in renal stone formation and the need to include its determination in regular examinations of stone formers must be stressed. Treatment of hyperoxaluria is both medicinal and dietetic : control of oxalic acid-rich food intake and reduction of the intestinal absorption of oxalate caused by calcium-deprived diets. The diet must be completed by therapeutic measures aimed at reducing the oxaluria and increasing the urinary factors preventing crystallization.

Diet↗
PubMed1983

Alterations in circadian rhythmicity in calcium oxalate renal stone formers.

The circadian (circannual for oxalic acid) variations of 13 urinary variables (volume, creatinine, calcium, oxalic acid, glycolic acid, 17-ketosteroids, 17-hydroxycorticosteroids, phosphates, urea, uric acid, chloride, sodium, and potassium) have been documented in 7 calcium oxalate renal stone formers and 7 healthy men (control group). Urine was collected every 4 h over a period of 24 h. All subjects had the same synchronization: diurnal activity from 07(00) to 23(00) +/- 1 h and nocturnal rest; meals were given at fixed clock hours (08(00), 12(30) and 20(00) +/- 1 h). A statistically-significant rhythm (p less than 0.05) was validated for all variables except urea and calcium in healthy men. In renal stone formers, 6 variables (calcium, oxalic acid, and glycolic acid in particular) had no detectable circadian rhythm. However, a periodicity of c. 8 h (ultradian rhythm) was demonstrated for calcium and oxalic acid with peaks being located around 02(00), 10(00), and 18(00). No circannual variations in oxalic acid output could be observed. The present study shows an alteration of the periodicity of calcium and oxalic metabolisms, i.e. the loss of a circadian (24-h) rhythm and the occurrence of an ultradian rhythm of 8 h. The risk of calcium-oxalate crystallisation appears thus greater at 02(00), 10(00), and 18(00). Furthermore, any study dealing with oxalic acid excretion should state the season of urine collection when comparing renal stone formers and healthy subjects, as significant differences in oxaluria may appear during the summer months and not during the rest of the year.

Adult↗
PubMed1977

Radioimmunological determination of urinary tetrahydroaldosterone.

A method is presented for radioimmunological determination of 3alpha, 5beta-tetrahydroaldosterone. It is based upon the reactivity of this steroid with an antiserum induced by the 3-carboxymethyloxime of 18, 21-aldosterone diacetate conjugated with bovine serum albumin. One hundred microliters of urine enzymatically hydrolyzed with an helix pomatia preparation, containing tritiated tetrahydroaldosterone for the yield calculation, were extracted with dichloromethane and chromatographed on a small celite column. The yield after extraction and chromatography was 64 +/- 17%. The radioimmunological determination was carried out in a conventional manner. The method is specific, sensitive (10 pg/tube), exact, reproducible, very simple and extremely rapid. The results showed good agreement with values given by a colorimetric method (p less than 0.001). The median value measured in 45 healthy adult subjects under standard sodium diet was 53.3 microgram/24h (95 % of the population within a 16.6 to 131.1 microgram/24h range). In 78 cases of adrenocortical insufficiency, 60 cases of obesity and 28 cases of hypokalemia, the median values (and the ranges : microgram/24h) were respectively 7.7 (1.0 - 51.0), 80.9 (17.0 - 503.0) and 64.3 (8.0 - 181.0). In 330 hypertensive patients the excretion of tetrahydroaldosterone exceeded the normal range in 115 cases (35%) with a median of 199.7 microgram/24h (131 to 620 microgram/24h).

Aldosterone↗
PubMed1977

[Metabolism of o,p'-DDD (mitotane) in human and animals. Actual notions and practical deductions (author's transl)].

The metabolism of o,p'-DDD (mitotane), a well-known inhibitor of adrenal steroidogenesis in man and animal, is reviewed. Following oral administration, about 65% of the ingested drug were found to pass in the stool. The drug appeared in the urine in metabolized forms: o,p'-DDA and mono-and dihydroxylated derivatives of o.p'-DDA. These latters were found as well in the stools. An unsaturated metabolite, o,p'-DDE was described in plasma and tissues in man. Serum specimens of treated patients were analyzed for o,p'-DDD during various phases of therapy: the levels and the rate of rise during treatment were very variable (5 to 90 microng/ml). Tissue levels were obtained from animals (rats, dogs) or men (biopsy as well as autopsy): o,p'-DDD was primarily found stored in adipose tissue and fat-containing tissues, essentially adrenals. Practical conclusions can be drawn from these results: there is no correlation between the dose of o,p'-DDD administered and its blood level; there is no correlation between blood levels and the patient's responsiveness to the drug; there is a possibility that the molecule transformed in an active metabolite through its metabolism.

Animals↗
PubMed1976

Anti-adrenocortical activity of SKF 12185 and SKF 252 A.

The synthesis of aldosterone and 18-hydroxycorticosterone from triated corticosterone by sheep adrenal homogenate have been studied in presence of increasing concentrations of SKF 12185, a product already known as an inhibitor of cortisol synthesis. An approximately 98% inhibition of the synthesis of both steroids occurred with only 2 x 10(-4) M of the drug. In contrast, incubation of a structurally closely related compound (SKF 252 A) under the same experimental conditions resulted in an only 52% inhibition with higher concentrations (2 x 10(-3) M). These findings could explain the marked aldosterone fall that occurs in SKF 12185 treated subjects and supports the therapeutic use of this product in treatment of hyperaldosteronism.

18-Hydroxycorticosterone↗
PubMed1976

[Production of antihaptene antisera. Comparison of methods of immunisation (author's transl)].

Five immunogenic substances were injected to rabbits. The method of immunisation by the intradermal route at 30 to 50 different points, with low doses of immunogen, without booster, does not seem to lead to production of antiserum of great specificity. The choice of the dose of immunogen to be injected is difficult, owing to our ignorance of the immunogenic dose for a given immunogen. The method of immunisation by the subcutaneous route with high doses followed by a booster, leads to more constant results, comparable to those obtained by the first method to which one may associate boosters by the subcutaneous route. The titers, affinities and specificities of the antisera thus produced are sufficient for the development of radio-immunoassay. The characteristics of the antisera obtained, related to the quality of the immunogen, do not seem to depend on the method of immunisation.

Angiotensin II↗
PubMed1976

[Radioimmunoassay of tetrahydroaldosterone in urine].

A radioimmunoassay for urinary tetrahydroaldosterone is described. An antiserum, elicited by a 3-carboxy-methyloxime 18-21 aldosterone diacetate conjugated to bovine serumalbumine, with which tetrahydroaldosterone cross reacts, is used. The method is specific, sensitive (10 pg/tube), accurate, reproducible (7%), thus allowing sufficient reliability for clinical applications. In 19 normal adults subjects under unrestricted sodium intake, the urinary tetrahydroaldosterone averaged 59,8+/-29,4 mug/24 h.

Adult↗