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Resume Le dosage de l’iode urinaire ne fait plus partie du bilan de base de l’exploration des sujets hyperthyroidiens, remplace par les dosages hormonaux et la scintigraphie. En utilisant une methode colorimetrique sur microplaques, nous avons cherche a montrer que ce dosage pouvait presenter un interet dans le diagnostic differentiel de certaines pathologies. Nous avons montre que les concentrations de l’iode urinaire ne sont pas differentes entre euthyroidiens et sujets presentant une maladie de Basedow. Chez les sujets avec une thyroidite subaigue virale ou auto-immune, l’iode urinaire est multiplie par 3 et par 10 pour les patients presentant une surcharge iodee. Dans les thyroidites, l’iodurie est maximale au moment de la poussee aigue et le suivi des concentrations permet d’evaluer l’atteinte du tissu thyroidien et l’efficacite therapeutique.

Hormonal changes, substrate mobilization and energy metabolism were studied inturbot Scophthalmus maximus exposed to 3 hypoxic conditions (oxygen partial pressure in water,PwO 2 = 90, 60 and 30 mm Hg) followed by recovery under normoxia. Measurements of the blood pH,total CO 2 concentration, arterial oxygen partial pressure, hematocrit, glucose, lactate, and ‘stress’hormones (cortisol, adrenaline and noradrenaline) plasmatic concentrations were performed. High-energy phosphorylated compounds, glycogen, glucose and lactate concentrations were also deter-mined in liver and white muscle tissues. Exposure to 90 or 60 mm Hg did not induce any majorphysiological change, as hyperventilation by itself could compensate for the decrease in wateroxygen tension. At 30 mm Hg, marked increases in cortisol, adrenaline and noradrenaline concen-trations, associated with a decrease in blood arterial oxygen partial pressure, were observed. Duringexposure to 30 mm Hg, turbot resorted to anaerobic metabolism, resulting in liver glycogen depletionand lactate production. This mechanism appeared to be efficient enough to produce energy, as nosignificant change in phosphorylated compounds and adenylate energy charges in muscle and livercould be observed. These results indicate an absence of metabolic depression in turbot downto 30 mm Hg and confirm the high capacity of this species to cope with low water oxygen tension.KEY WORDS: Hypoxia · Anaerobiosis · Catecholamines · Cortisol · Lactate · Turbot

L’efficacite de la coloscopie, principal examen de diagnostic et de depistage des affections coliques, depend etroitement de la qualite de la preparation. Les facteurs influencant l’efficacite de cette preparation sont divers (experience de l’operateur, action du produit prescrit pour la preparation, acceptabilite et observance des modalites de la preparation par le patient).

Resume Les adenocarcinomes mammaires s'accompagnent frequemment de localisation metastatiques osseuses. La determination urinaire de marqueurs specifiques de la resorption osseuse a ete decrite dans le diagnostic et le suivi de ces metastases. Le Crosslaps (TM) , produit de degradation de l'extremite C-terminale du telopeptide du collagene de type I, fait partie de ces marqueurs. Cependant le recueil des urines reste toujours delicat et la mesure au niveau serique est preferable. En utilisant une methode immunoenzymatique pour le dosage serique du Crosslaps (TM) , nous avons compare chez 45 femmes presentant un cancer du sein, les concentrations de ce marqueur au niveau serique (S-CTX) et urinaire (CTX). Comme pour le CTX, les concentrations en S-CTX sont plus elevees chez les femmes avec metastases. Les variations du S-CTX sont un bon reflet de l'efficacite de la chimiotherapie. Cependant, compare a l'imagerie, le S-CTX a la meme specificite que le CTX (96 %) mais une sensibilite plus faible (81 % versus 95 % pour le CTX).

Multiple myeloma causes extensive bone remodeling. Classical biochemical markers such as urinary calcium have poor sensitivity for detecting multiple myeloma bone remodeling. New biochemicals have been developed including a carboxyterminal telopeptide of collagen I (CTX). We used an immunoenzymatic assay to determine urinary CTX in 60 patients with multiple myeloma. This marker was evaluated with regard to total pyridinolines, urinary calcium, radiological features, pain and response to treatment with bisphosphonates. In patients with bone involvement, CTX concentrations were significantly higher (+230%) than those of deoxypyridinoline (DPD) (+175%) and pyridinolines (PYD) (+130%). In all patients we have found a close correlation between CTX and DPD but not between CTX and PYD. Compared to radiological features, CTX was more sensitive (97%) and specific (96%) than DPD. After treatment by bisphosphonates, the fall in CTX concentrations was paralleled to urinary calcium and more marked than pyridinolines. Although our results need to be confirmed, CTX appears to be a potential marker to explore bone involvement in multiple myeloma.

In modern medicine the undeniable value and indispensability of scientific investigations are now universally recognized both for diagnostic purposes and monitoring of disease and in basic epidemiology. The direct treatment of patients is an undeniable task of doctors in medicine. Progress in laboratory science is largely the result of contributions by scientists with an adequate education and specialisation in the field, i.e. by clinical chemists. Clinical laboratory science has developed on a broad front throughout the European Community, resulting in significant differences in what constitutes a national clinical chemistry service in each state. Clinical chemistry is the medical discipline devoted to obtain, explore and employ chemical knowledge and chemical methods of investigation, in order to procure knowledge about normal and abnormal chemical processes in man. These processes are studied on a general level, in order to get insight into human health and disease, and on a patient-specific level for diagnostic or monitoring purposes. The delimitation of clinical chemistry varies from country to country, since there is no sharp boundary to haematology, immunology, molecular biology and microbiology. One of the main tasks of the clinical chemist is direction and supervision of a laboratory department in a hospital or health service (public or private), where his role involves bridging the gap between rapidly developing laboratory science and technology and the growing knowledge on characteristics of disease. He must possess fundamental biochemical knowledge and have the ability to use this knowledge most appropriately as applied to clinical requirements, i.e. diagnosis of disease and planning and monitoring of therapy. Apart from providing a competent laboratory service, the clinical chemist must be able to function as a consultant to his clinical colleagues and liaise with them in the interpretation of laboratory results. His advice and professional consultation have at least three aspects, i.e. choosing the most appropriate laboratory investigation in a certain case, ensuring that the analyses are performed in the best possible way and correctly reported and, finally, providing information and (most important) interpretation on the significance and consequences of the laboratory data obtained. As the results of laboratory investigations and the consultation of the clinical chemist have a direct and important influence on the treatment of the patient, it is to the benefit of the public that the profession of the clinical chemist is duly regulated.

resume Les adenocarcinomes mammaires s'accompagnent, dans environ un tiers des cas, de localisations metastatiques osseuses de nature osteoclastique. La scintigraphie osseuse aux biphosphonates marques au 99m Tc reste la methode de reference pour depister et localiser ces metastases. Recemment, divers marqueurs biochimiques sont apparus, qui permettent une etude du remodelage osseux. Le Crosslaps ™ , produit de degradation de l'extremite C-terminale du telopeptide du collagene de type I, fait partie de ces marqueurs. En utilisant une methode immuno-enzymatique, nous avons pu mettre en evidence chez 50 patients une bonne correlation entre l'aspect scintigraphique et la concentration urinaire en Crosslaps ™ . Le suivi de ces patients pendant leurs cures de chimiotherapie nous a permis de montrer qu'un dosage regulier du Crosslaps ™ est un bon reflet de l'evolution des metastases et de l'efficacite therapeutique.

In liver and serum, AST activity is dependent on two isoenzymes, which are mitochondrial and cytosolic in nature. In an attempt to explain the well-known increase of serum mitochondrial AST-to-total AST ratio in chronic alcoholism (which is due to a specific increase of the mitochondrial isoenzyme), we analyzed: (a) liver and serum AST, ALT and glutamate dehydrogenase activities in 23 active drinkers with minimal liver changes, 11 alcoholic patients with cirrhosis who had stopped drinking, 18 nonalcoholic patients with viral chronic hepatitis and 11 subjects with normal livers; and (b) the expression of messenger RNAs for AST isoenzymes in the corresponding liver samples. Enzymatic activities were decreased in the liver irrespective of the origin of the liver disease. In patients with viral chronic hepatitis (or in those with alcoholic cirrhosis when abstinent), variations in liver proteins and messenger RNAs paralleled significant decreases in mitochondrial AST, ALT and glutamate dehydrogenase and a nonsignificant decrease of cytosolic AST. In alcoholic patients with minimal liver changes, the significant decrease of hepatic cytosolic AST, ALT and glutamate dehydrogenase activities contrasted with a close-to-normal liver mitochondrial AST activity; the increased amounts of mitochondrial AST messenger RNA give evidence for a pretranslational mechanism of regulation, indicating a possible increase in the total production of mitochondrial AST in the liver. The decrease of hepatic cytosolic AST activity was statistically significant only in alcoholic patients without cirrhosis who had a normal cytosolic AST mRNA level, thus suggesting a contributory role of translational or posttranslational regulation. In conclusion, regulation of AST isozymes during liver disease is complex, including differential, pretranslational and translational or posttranslational mechanisms. (HEPATOLOGY 1991;14:620–625.)

Many authors have stressed the role of serotonin in mood disorders and some aspects of schizophrenia. Cerebral serotonin synthesis depends on the quantity of circulating free tryptophan not bound to albumin. It thus appeared interesting to estimate the two forms of tryptophan by measuring their plasmatic concentration as well as the free/total tryptophan ratio. These evaluations were performed by an automatic spectrofluorimetric method. 19 blood samples were analyzed from normal subjects and 47 from schizophrenic or manic-depressive patients including treated and untreated cases. The only significant differences in the free/total tryptophan ratio were reported in untreated paranoid schizophrenics and in anxiety cases. A dual nosological and symptomatical approach was adopted in the course of attempted correlation with biological data in order to underline the possible role of symptomatic elements common to different diagnoses. The results for melancholia agreed with those reported in the literature (4). In the case of schizophrenia, however, there are only a few reports and no discrimination has been made between untreated and treated patients or between the different types of schizophrenia. The clinical picture is different for paranoid schizophrenia which is the delusive aspect of the disease and for hebephrenic schizophrenia. It seems fairly logical to find opposite results in delusive mania and paranoid schizophrenia compared to melancholia, since delusive mania and paranoid schizophrenia have similar symptomatology which is the opposite of that found in melancholic depression.

One of the pathways of tryptophan catabolism induced formation of tryptamine (T) then, after the action of monoamine oxidase (MAO), indolacetic acid (IA). The study of T/IA can permit an appreciation of MAO activity. After the determination of reference values, we studied different syndromes. In phenylketonuria (PKU), T/IA is very low with a decrease of T and an increase of IA; in carcinoid syndrome the results are more variable but in several cases the decrease of MAO activity is likely; in different dermatological diseases, we observe abnormal values, especially in scleroderma and acrosclerosis.

Atomic absorption spectrometry was used to measure magnesium, calcium, and sodium, and emission spectrometry to measure potassium, in myocardium (left and right ventricles) of 26 control subjects who died of acute trauma. Results were expressed in mumol/g of proteins. Mg/Ca and K/Na ratios were also determined. The same measurements were made in 24 patients who died from acute myocardial infarction. Samples were also taken from the necrotic area. Mg/Ca and K/Na ratios were significantly higher in the left ventricle of both populations, thus providing evidence of anatomical and physiological differences between the two ventricles. As a result of cytolysis and anoxia, the Mg/Ca ratio was very significantly inverted, and the K/Na ratio very significantly smaller, for samples from the necrotic area. In these clinical conditions arrhythmias could certainly be considered likely, and there is reason to believe that magnesium depletion may be a cause of arrhythmias.

High-performance liquid anion-exchange chromatography is combined with continuous flow spectrofluorometry at an optimalized pH for the determination of 5-hydroxyindoleacetic acid (5-HIAA) in urine. Its chief advantages are speed (7 min per determination), enabling measurement of large series of samples, precision (coefficient of variation = 0.72%), sensitivity (detection limit: 1 pmol) and specificity (no interference with 5-HIAA precursors or with the drugs tested). Reference values ( n = 112) are 25 ± 20 μmol per 24 h. Comparison with a reference spectrofluorometric technique shows a correlation coefficient of 0.96.

Glucocorticoid hormones increase the activity of cytosolic aspartate aminotransferase (cAspAT) in the Fao rat hepatoma cell line. Maximal increase (6-10-fold) was observed 48 h following the addition of the glucocorticoid agonist dexamethasone at a concentration of 0.1 microM. The effect of dexamethasone was specific since it was not mimicked by sex steroids and was inhibited by the glucocorticoid antagonist RU 486. Insulin (0.1 microM) inhibited by more than 50% the induction of cAspAT by glucocorticoids. The cAMP analog, 8-bromoadenosine 3',5'-monophosphate (Br8cAMP, 0.5 mM), potentiated the effect of dexamethasone (2-3-fold) and partially relieved the inhibitory effect of insulin on the induction by dexamethasone. Both insulin and Br8-cAMP had no significant effect on basal activity. The mitochondrial isoenzyme was insensitive to the various hormonal treatments. Northern blot analysis revealed the presence of two major (2.1-kb and 1.8-kb) and one minor (4-kb) mRNA species hybridizing with a rat cAspAT probe. The regulation of these mRNAs by glucocorticoids, insulin and cAMP correlated with the variation of the cAspAT activity, suggesting that these hormones act at the pretranslational level. We compared the regulation of cAspAT mRNAs with those of tyrosine aminotransferase mRNA. Both were similarly increased by dexamethasone but the latter was also increased by cAMP even in the absence of the glucocorticoid agonist. In addition, the increase in tyrosine aminotransferase mRNA was inhibited by cycloheximide whereas the increase in cAspAT mRNAs was not. These results show that there are significant differences in the regulation of cAspAT and tyrosine aminotransferase by glucocorticoids and other hormones, although both enzymes probably contribute to the same metabolic pathway.

Growth of the fastidious enteric adenoviruses 40 and 41 was compared in different human cell lines. Purified virions were used to infect the following cell lines: A549; KB; Chang's conjunctiva; 293; HeLa. Both types of enteric adenovirus were infectious for each cell line, with the exception of adenovirus 40 in HeLa cells. Relatively low infectious titers were obtained from each cell type following infection with adenovirus 40 (TCID50 average = 10−1.5), whereas adenovirus 41 replicated to significantly higher titer (TCID50 average = 10−3.0). For both viruses, the highest infectious titers were obtained with A549 and KB cells. A time course experiment performed to quantitate the amount of hexon present in A549 and KB cells infected with each virus indicated that while the kinetics of accumulation were similar for both viruses, the concentration of type 41 hexon was significantly greater than that for type 40 in either cell line. The concentration of type 41 hexon was similar in each cell type; for type 40, a greater concentration of hexon was obtained in the A549 cell line than in the KB cells. The results indicate the distinct replication characteristics exhibited by adenovirus 40 are not due to a restriction in a specific host cell, and, because purified virions were used, not attributable to interference that might occur with co-infection from multiple viruses present in the same clinical specimen. We conclude the differences observed in the replication of these viruses are independent of host cell type and are associated, uniquely, with each virus.

Cells infected with herpes simplex virus, respiratory syncytial virus and adenovirus were subjected to several cryogenic regimens to determine whether these procedures were detrimental to the performance and results obtained with an indirect immunofluorescence assay (IFA). Infected cells were harvested and divided into equal aliquots prior to freezing at different temperatures (-20, -70 and -165 degrees C). Cells fixed onto glass slides immediately after harvesting were used as controls. For the IFA, cells were thawed and fixed onto glass slides immediately prior to reaction with an appropriate virus-specific antibody and, subsequently, an FITC-conjugated anti-species antibody. The virus-infected cells retained their structural integrity following the experimental cryogenic regimens and were useable in the IFA. The quality of the image and the intensity of the fluorescent signal were enhanced by the incorporation of dimethyl sulfoxide into the freezing medium; cells frozen at -165 degrees C with DMSO gave the most satisfactory IFA results, although cells frozen at either -20 or -70 degrees C with DMSO were also useable. The use of cells frozen at the experimental temperatures in either phosphate buffered saline or tissue culture medium resulted in IFA substrate slides of diminished quality, often with a blurred image and distorted cellular morphology. We conclude that freezing of virus-infected cells prior to preparation for IFA is not detrimental to the performance of this procedure and the interpretation of immunological reactivity.