Méthode rapide de dosage de l'acide oxalique urinaire par Chromatographie en phase gazeuseRapid method for the determination of urinary oxalic acid by gas liquid chromatography

A rapid method for the determination of urinary oxalic acid by gas-liquid chromatography is described. The procedure involves extraction of oxalate from urine by tetrahydrofuran followed by evaporation to dryness and subsequent diesterification with the boron-trifluoride propanol. The derivative is extracted with hexane and is detected by FID gas chromatography. Malonic acid is used as internal standard. Analytical recovery ranged from 94 to 105%. The coefficient of variation in replicate aliquots over the entire range is less than 6%. The expected range for our method is calculated to be 44 to 577 μmol of oxalate per 24-h urine.     

Evolution du magnesium serique et erythrocytaire chez les brulesEvolution of serum and erythrocyte magnesium levels in burn patients

The study of the evolution of serum and erythrocyte magnesium in burn patients shows there exists, immediately after the thermic aggression, a reduction in the concentration of this cation. The hypomagnesemia is generally moderate and short; return to values considered normal is usually registered from the third day. Variations of the serum level are similar to those induced after a surgical operation. The hypomagnesemia following burns probably belongs to the same physiopathological mechanism as the one noticed after surgical aggression.The hypothesis according to which there could exist a link between hypomagnesemia and a number of neuropsychiatric manifestations met simultaneously in the same patient cannot be excluded.     

Determination potentiometrique de l'antigene de surface de l'hepatite B dans les liquides biologiquesPotentiometric determination of hepatitis B surface antigen in biological fluids

The present report describes a sensitive and reliable method for potentiometric determination of hepatitis B surface antigen in biological fluids, as an application of enzyme-linked immunoassay technique by a “sandwich” procedure. Specific antibodies are immobilized on a gelatine membrane which covers the sensor of an iodide-sensitive electrode. After immersion of the modified electrode in a dilute solution of antigen, the enzymatic activity is evaluated in a solution of peroxidase-labelled antibodies, in the presence of substrate and iodides. The electrode potential is a function of antigen concentration in the solution. This new procedure should find its application in the determination of substances present in very low concentration in biological fluids.     

Dosage par chromatographie gazeuse avec détection en photométrie de flamme de l'acide alpha-céto-gammam-méethylthiobutyrique urinaire dans les hyperméthioninémiesDetermination of urinary α-keto-γ-methylthiobutyric acid in hypermethionemia by use of gas chroma tography and flame photometry

In this paper we describe the determination of urinary alpha-keto-gammamethylthiobutyric acid (ACMTB) by the use of gas chromatography of its quinoxalinol derivative and specific detection of sulphur with a flame photometric detector.Using these techniques, it was possible to study the urinary elimination of this secondary metabolite of methionine in normal children, homocystinurics and in one case of hypermethioninemia.The excretion of ACMTB is normally very weak and is strongly increased when the principal pathway of methionine is blocked.     

Influence des contraceptifs oraux sur la concentration des acides amines granulocytaires chez les femmes supposees sainesInfluence of oral contraceptive agents on the concentration of amino acids in leukocytes of supposedly healthy women

The concentration of amino acids has been measured m leukocytes of women taking oral contraceptive agents and also in controls. These assays were made by means of ion exchange chromatography. The amino acid pool in leukocytes was found to be smaller in those patients taking the “pill”. Each amino acid concentration decreased except for taurine and glutamine. Taurine represented 64.1% of the pool in treated women and only 23.5% in controls. Glutamine represented 9.5% of the pool in patients and 3.7% in controls.     

Heterogeneite des chaines glycanniques des mucines bronchiques acides isolees a partir de l'expectoration de deux sujets atteints de bronchite chronique

Acidic glycoproteins having blood group H activity were isolated from the sputum of two patients suffering from chronic bronchitis by reduction of the fibrillar mucus, chromatography on ECTEOLA-cellulose and gel filtration on Sepharose 4-B. These glycoproteins were degraded with alkaline borohydride and the degradation products were fractionated by chromatography on ionexchange resins and by gel filtration. The carbohydrate chains have a wide heterogeneity with regard to acidity and molecular size. Therefore carbohydrate chain heterogeneity which was already observed for bronchial glycoproteins isolated from a patient suffering from cystic fibrosis is not specific for cystic fibrosis.     

Behavior of fetal hemoglobin during isoelectric focusing

The results of isoelectrofusing applied to haemolysates of newborns, a case of beta thalassaemia and a case of hereditary persistence of fetal haemoglobin show that fetal haemoglobin F(alpha 2 gamma 2) can be oxidized into two products. The first corresponds to fetal ferrihaemoglobin (alpha +2 gamma +2), the oxidation product of the four Fe atoms of the molecule. The second, which is called fetal intermedial methaemoglobin, and has the same pH as adult ferrihaemoglobin A1, represents probably a product of partial oxydation of fetal haemoglobin.     

Etude des isoenzymes de l''amylase dans une tumeur pulmonaire secretante d''amylaseAmylase isoenzyme analysis in an amylase-producing tumour

The plasma and pulmonary tumour are studied in a patient with lung metastasis. An abnormal and neuraminidase-sensible isoenzyme is noted both in plasma and tumour.

Homogenates obtained from the tumour by two different mechanic disruption procedures denote an easier liberation for the salivary type isoenzymes than for pancreatic types. It is suggested that the salivary enzymes are synthesized in the cytoplasm during many inflammatory processes and secreted without cellular necrosis.     

Determination of lysozyme in biological fluids by a semi-automatic kinetic technique. Discussion of the method (author's transl)]

A rapid and semi-automatic determination of lysozyme in biological fluids using kinetic analysis and turbidimetry is described and compared to other commonly used techniques. The specificity of the method is satisfactory while that of clarification of a gel medium is apparently not. Normal values and standard errors for plasma, urine, and leucocytes are given. A standardised expression of lysozyme activity is proposed and discussed. The importance of the means by which the blood sample is collected and prepared is underlined: plasma, decanted soon after collection, is preferable to serum.     

Postprandial variations in serum bile acid levels in humans free of hepatic or intestinal diseases (author's transl)

The levels of unsulfated, free or conjugated cholic, deoxycholic and chenodeoxycholic acids were measured using gas chromatography in 39 humans free of hepatic or intestinal diseases before and 10, 60, 120 and 180 min after ingestion of a standard meal. The probable maximal levels were determined with an error risk lower than 0.05. In fasting subjects, the observed values are comparable with those obtained by other authors working with gas chromatography or radioimmunoassay. Meal ingestion does not influence in the same way the serum levels of the various bile acids: the chemodeoxycholic serum level rose significantly in all cases whereas cholic and deoxycholic serum levels rose only in two-thirds of observed subjects; 60 and 120 min after the meal for chenodeoxycholic acid, and only 60 min after the meal for cholic acid, the mean values are significantly higher than the fasting ones; 120 min after the meal, the chenodeoxycholic and total bile acid probable maximal levels (respectively 7.4 and 10.3 micrometer) are twice the fasting ones. The cholic to chenodeoxycholic serum level ratio is nearly always lower than 1 but may reach 3. On the basis of these results, the validity and efficacy of the exploration tests based on serum bile acid level determinations are discussed.     

Heterogeneity of glycogenosis with alpha-1,4-glucosidase deficiency: enzymatic studies in three families (author's transl)]

The authors describe four cases of atypical forms of glycogenosis with alpha-1,4-glucosidase (acid maltase) deficiency. The results of clinical, microscopic, histochemical, enzymological and immunological studies are described. Acid maltase activity has been studied in muscle, leukocytes and fibroblasts. The authors show no difference in the properties of acid maltase; the authors study the purified enzyme from various tissues.     

Comparison of the EMIT test with high-performance liquid chromatography for the determination of phenobarbital in serum.

The new enzyme immunoassay technique (EMIT) is compared to high-performance liquid chromatography used for determining phenobarbital in serum. After resuming the methods of both techniques, we compare the results of 116 sera collected from patients receiving treatment for epilepsy. The equation of the correlation curve is: HPLC = 0.98 EMIT + 0.12. The reliability characteristics are comparable. The enzyme immunoassay technique is less specific but more practicable.     

Fast and accurate method for theophylline analysis in preterm babies using gas chromatography and nitrogen selective detector (NFID) (author's transl)

The combined utilization of (a) a weak polar OV-1 phase, (b) an on-column methylation using a methylating agent commercially available, (c) a nitrogen selective detector (NFID) and (d) a small volume of sample, allows the development of a fast (less than 20 min) and accurate method for theophylline analysis in preterm babies. With 50 microliter of capillary whole blood sample, its limit of sensitivity was 0.5 microgram/ml of theophylline. This method is most desirable for theophylline monitoring in treating apnea of premature infants.     

Dosage de l'activité adénosine désaminasique dans les érythrocytes et les lymphocytes humains

A radiochromatographic method is described for measuring enzymatic activity of adenosine deaminase in human erythrocytes and lymphocytes. [8-¹⁴C]-adenosine is converted into inosine and hypoxanthine; after Chromatographie separation of the products, the radioactivity is determined.The kinetic properties of the enzyme have been studied. The K_m values for the erythrocyte and lymphocyte enzymes are higher as compared with purified deaminase. Optimum conditions for substrate concentration for assay were established.The mean normal activity (± S.E. of mean) is: for erythrocytes, 494 ± 61; nmol min^-1 ml^-1; for lymphocytes, 147 ± 0.18 nmol min^?1 10⁶ cellules.The mean values are higher than that given by other methods working at a lower (non-staurating) substrate concentration.     

Radiocompetitive assay of sulfamido-3-chloro-4-benzoic acid with carbonic anhydrase as binding reagent (author's transl)]

The control of patients treated by diuretic sulfonamides can be carried out by a radiocompetitive assay using their binding properties to carbonic anhydrase (CA). In this paper we have studied the assay of sulfamido-3-chloro-4-benzoic acid (SD3) using dialysis equilibrium as separation procedure. With (CA) 2 X 10(-6) M and 14C-SD3 0.5 X 10(-6) M (specific activity: 2 muCi/mg), can be detected 0.5 X 10(-6) M of (SD3) in the assay medium. 6.5 mg protein present in serum lower the assay sensitivity twenty times, owing to an elevated value of the affinity constant, Ka, of albumin-(SD3) complex (10(3) mol-1). On the other hand, the molecules with sulfamidobenzoic group cannot be differentiated in this procedure.     

La bilirubine erythrocytairE: Ses variations — interet pratique de son dosageErythrocyte bilirubin: practical implications of variations in concentration

The values of red blood cell bilirubin and unconjugated plasma bilirubin have been measured simultaneously in 31 blood samples of 21 new-born infants with deep jaundice. The methods of measurement used by the authors have proved quite reliable and there is good correlation between both values. The concentrations rise together with the bilirubin/albumin molecular ratio. Nevertheless even with a low ratio, the red blood cell bilirubin rises to high levels when acidosis is present.     

Intérêt de la détermination de la protéine C réactive en traumatologie crânienne

Serum C reactive protein can be assayed precisely and specifically by immunonephelometry.This protein was determined daily for four days in 102 patients suffering of a skull trauma.Skull trauma without any complication (n =43) did not lead to a significant increase of C reactive protein level, in contrast to skull trauma complicated by an intracranial haematoma (n = 32), in patients with profound coma (n = 17) and in cases leading to a fatal issue (n = 10). C reactive protein concentrations in uncomplicated skull trauma were found to be significantly different from those of the three series of complicated situations. C reactive protein patterns were correlated with the evolution of the trauma.It is therefore recommended that C reactive protein concentrations in serum should be determined daily during four days following the accident.     

L'acide xanthurenique urinaire,determination des taux normaux en fonction de l'age et du sexeDetermination of normal levels of urinary xanthurenic acid as a function of age and sex

A quantitative determination of xanthurenic acid in human urine has made possible a statistical study of the secretion of this substance according to age and sex.     

Determination precise du rapport lecithine/ sphingomyeline dans le liquide amniotique: Proposition d'une methode de referenceExact determination of the lecithin Isphingomy elm ratio in amniotic fluid. Suggestion of a reference method

Pulmonary maturity of the fetus can be evaluated by the lecithin/sphingo-myelin (L/S) ratio in amniotic fluid. To existing methods of lipid extraction, precipitation with acetone and chromatography, we add a simple and accurate estimation of sphingomyelins (S) and precipitated lecithins (Lp) without acid digestion. The method is reproducible (C.V. < 9%) for the measurement of Lp/S ratio and gives with accuracy the concentrations of Lp, avoiding possible errors in interpretation of Lp/S. Our results show that at 35 weeks of normal gestation, Lp/S ratio is about 2 and Lp concentration, 10 mg/l.     

Utilisation du cellogel R.S. triangulaire pour l'etude de la proteinorachie dans la panencephalite sclerosante subaigue: Resultats et perspectivesUse of Cellogel R.S. wedge strips to study the cerebrospinal fluid proteins in subacute sclerosing panencephalitis: Results and perspectives

A simple, rapid and sensitive method of electrophoresis is described using Cellogel R.S. “wedge strips” to study cerebrospinal fluids. This support medium is able to produce multifractionation of C.S.F, proteins, particularly γ-globulins, this having great significance with regard to subacute sclerosing panencephalitis (S.S.P.E.) and multiple sclerosis.Forty six C.S.F, samples from African people have been studied using this method, after concentration of the samples by vacuum dialysis. The normal African group showed similar results to those of the Europeans, but γ-globulins, which represented 17.3% of total proteins, were significantly higher than in the case of European people. In 10 cases of S.S.P.E., electrophoresis using Cellogel R.S. “wedge strips” showed in all cases in the slow γ-globulin area, several (2 to 7) subtle and deep bands, with constant mobilities, which seem to be the C.S.F, symptom of this disease.