Comparison of plasma and follicular fluid hormone profiles following stimulation with HMG, with or without LHRH agonists, for in-vitro fertilization.

Plasma and follicular fluid (FF) hormone assays for follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), oestradiol (E2), progesterone (P), delta-4-androstenedione (A4) and testosterone (T) were performed on the day of oocyte retrieval in two groups of normo-ovulatory women enrolled in an in-vitro fertilization (IVF) programme: 24 were treated using the decapeptyl agonists DTRP6, of luteinizing hormone-releasing hormone (LHRH) in the long protocol associated with human menopausal gonadotrophin (HMG) (49 FF) and 14 were stimulated with HMG alone (33 FF). In both FF and plasma the mean concentration of P was greater, and the E2/P ratios as well as the LH levels were lower in the agonist-treated group. In this group the follicular concentration of P was greater and the E2/P ratio lower when pregnancy occurred following IVF. The hormonal modifications may be due to greater functional maturity of the granulosa cells.

[Update of a selected technique for uric acid determination in plasma and serum. Experimental study and value of derivative spectrophotometry]. / Mise au point d'une technique sélectionnée de dosage de l'acide urique dans le plasma et le sérum. Etude expérimentale et intérêt de la spectrophotométrie dérivée.

A critical study of the candidate reference method for evaluation of uric acid in plasma proposed by the American Association of Clinical Chemistry is followed by testing in six laboratories. The dispersion of results is wide (CV greater than 5%). The importance of turbidity remaining after the deproteinization by trichloracetic acid is clearly demonstrated. This turbidity is really not reproducible from an operation to another one on the same serum. It is very likely responsible of the great dispersion of the results. After that, other deproteinization methods are tried. Ultrafiltration and ultracentrifugation give both defect errors because uric acid is in part bound to proteins. So it is necessary to find another technic which cancels the effects of turbidity on the absorbance readings in the ultra-violet domain. Experimental studies showed that uric acid may be evaluated with a good accuracy by derivative spectrophotometry, in lipid solutions as well as in cloudy ones. Turbidity was created by intralipid suspension additions. Various parameters hitting the method were examined (linearity, smoothing window...), taking as criterion the measure of overloaded serums at different levels. At last, the method is successfully transferred in several sites. In the case of blood serum, the respective influences of derivation and of repetition of final centrifugations are studied in order to estimate the effect of remaining turbidity. By the use of derivative spectrophotometry the improvement of the method of evaluation of uric acid proposed by A.A.C.C. is very noticeable; it reduces the variation coefficient between sites to less than 2%.

[Post-heparin LPL and HL activities after two months' treatment with gemfibrozil. Study in 6 normolipemic volunteers]. / Activités LPL et HL post-hépariniques après traitement de 2 mois par le gemfibrozil. Etude chez 6 volontaires normalipémiques.

Post-heparin lipolytic activities and lipidic parameters (cholesterol, HDL-cholesterol, triglycérides, Apo B) were studied in 6 human volunteers submitted to gemfibrozil treatment (900 mg once a day) during two months. Though lipidic parameters were not modified after treatment, gemfibrozil increased the LPL and HL plasmatic activities measured 10 minutes after heparin injection.

[A recommended method for determination of uric acid in serum]. / Méthode recommandée pour le dosage de l'acide urique dans le sérum.

SFBC work group on uric acid propose a method for evaluation in blood serum which is modeled on the one defined by American Association for Clinical Chemistry. Serum is deproteinized by trichoracetic acid and the supernatant, buffered to pH 8.5, is submitted to uricase action. The disappearing of the strong band of uric acid in UV is measured by derivative spectrophotometry; this procedure vanished the effect of trouble which remains in the supernatant. This spectrophotometric technic permit to reach, in multiple sites, a variation coefficient near of 1 p. cent.

Antibody against human lipoprotein lipase.

A polyclonal antibody against human lipoprotein lipase (LPL) was prepared. LPL from post-heparin plasma was first purified by heparin Sepharose 4B affinity chromatography. Protein impurities co-eluted with LPL were then eliminated by electrophoresis in the presence of ampholytes. Antithrombin III was identified in this fraction of protein impurities by immunodiffusion against a human antithrombin antiserum, while no antithrombin III could be detected in the purified LPL fraction. Immunodiffusion revealed a single line of precipitation between this antibody and human post-heparin plasma LPL. When pre-incubated with a constant activity of highly purified post-heparin plasma LPL (2.7 mU/75 microliters), an equal volume of the anti-LPL antiserum, either pure or diluted to 1/32 caused complete inhibition of the enzyme activity. Half maximal inhibition was observed at a dilution of approximately 1/200. By using a secondary antibody, it was shown that antiserum inhibited LPL activity by means of its immunoglobulins. This antibody was able to inhibit LPL from human adipose tissue, indicating that human LPL released from endothelial cell membranes has common antigenic determinants with adipose tissue LPL.

[Lipolytic and anticoagulant activities of heparin and one of its low molecular weight derivatives]. / Activités lipolytique et anticoagulante de l'héparine et d'un de ses dérivés de faible poids moléculaire.

The plasma lipolytic and anticoagulant activities following i.v. injection of either standard heparin or low molecular weight heparin (PK 10169) were compared in a study involving 10 healthy volunteers. The total lipolytic activity (lipoprotein lipase + hepatic lipase) released by PK 10169 was similar to that released by standard heparin when low molecular weight heparin was administered in doses 3- to 5-fold higher (by weight) than standard heparin. There was a dose-response relationship between the amount of PK 10169 injected and the level of plasma lipolytic activity. With doses of PK 10169 lower than 20 mg or heparin lower than 6 mg, lipolytic but not anticoagulant activity was observed. With doses higher than 20 mg with PK 10169 and 6 mg with heparin, both lipolytic and anticoagulant activities appeared. In doses where the lipoprotein lipase activities released by the 2 heparins were similar, the hepatic lipase released with low molecular weight heparin was significantly higher than with standard heparin.

Release of LPL activity after intravenous injection of a low molecular weight heparin.

A low molecular weight heparin (MW 4000-6000), PK 10169 (Pharmuka), with much reduced anticoagulant in vitro capacity, retains the properties of the standard heparin in releasing lipoprotein lipase and hepatic lipase activity after being injected intravenously.

[Routine urinary oxypurine assays for the detection of xanthine-oxidase deficiency (author's transl)]. / Déficit en xanthine-oxydase: dépistage systématique par le dosage des oxypurines urinaires. Deux nouveaux cas.

Xanthine-oxidase deficiency should be suspected whenever hypouricaemia coexists with hypouricuria and hyperoxypurinuria. In 18 months. Two new cases of xanthinuria were detected by routine urinary oxypurine assay among 10,000 patients where uricaemia was systematically tested. The xanthine-oxidase deficiency was associated with Hodgkin's disease in one case and with uncomplicated pregnancy in the other.

[Undetected cryoglobulinaemia may alter the serum protein results and mask dysglobulinaemia (author's transl)]. / Une cryoglobulinémie non soupçonnée peut fausser les résultats des protides sériques et faire méconnaître une dysglobulinémie.

By reporting a case of massive cryoglobulinaemia where precipitation of the cryoglobulins occurred at 35 degrees C but with no apparent clinical symptoms the authors want to draw attention to the fact that if cryoglobulinaemia remains undetected it may alter the serum protein results and mask dysglobulinaemia. However if protein electrophoresis is carried out at the same time, it is possible to detect a slight abnormality due to cryoglobulin fraction not entirely removed during centrifugation of the blood sample. This finding should incite one to look for cryoglobulins according to the usual procedure (at 37 degrees C) as well as to measure serum proteins on a sample also collected at 37 degrees C. Thus occasionally one happens to detect such dysglobulinaemia and if all results point to a diagnosis of myeloma -- as was the case here -- treatment can then be started early with advantage.

Biochemical problems caused by some cryoglobulins.

An unsuspected cryoglobulinaemia may be responsible for incorrect serum protein results and thus cause dysglobulinaemia to remain undetected. When cryoglobulins precipitate above laboratory temperature, they will be removed with the clot during centrifugation of the blood sample if they have not previously been suspected clinically or biologically. In the case of massive cryoglobulinaemia, one might find normal protein results but such results are incorrect and if only total protein estimation has been requested, dysglobulinaemia can remain undetected. However, if electrophoresis can also been carried out, a slight abnormality of the gamma globulin fraction might be observed and this ought to incite one to look for cryoglobulin by the usual method (i.e. at 37 degrees C), even in the absence of clinical evidence.