[Interference of hemoglobin variants on glycated hemoglobin measurement using Architect ci8200 immunoassay (Abbott Diagnostics)]. / Immunodosage de l'hémoglobine glyquée sur ci8200 (Abbott Diagnostics) en présence d'hémoglobines anormales.

The objective of this study was to compare haemoglobin A(1c) (HbA(1c)) levels measured by the immunoturbidimetric assay on ci8200 Architect (Abbott Diagnostics) to those obtained by the high pressure liquid chromatography (HPLC) assay from Tosoh Bioscience. Firstly, we verified correlation between the two methods in 47 subjects without hemoglobin variants: the coefficient of correlation was 0.968 and the regression equation was as follows: y(Abbott) = 0.928x(Tosoh) - 0.081. We then measured HbA(1c) levels by both methods in blood samples of 23 patients with a structural hemoglobin variant (A/S, A/C or S/C). Analysis of these samples revealed significant discrepancies between results of both methods, as indicated by the higher mean value obtained by immunoturbidimetric assay when compared to HPLC assay (7.17 +/- 2.68% vs. 5.86 +/- 1.41%). Classification of patients according to the HAS (French Haute Autorité de Santé) recommendations HbA(1c) was not modified for 68% of patients with abnormal hemoglobin. However, in 32% of cases, discrepancies between the two methods may have clinical importance, which justifies the occurrence of an abnormal hemoglobin when the HbA(1c) assay is performed by the method immunoturbidimetry Abbott Diagnostics.

Markers of oxidative stress in fit, health-conscious elderly people living in the Paris area. The Research Group on Ageing (GERBAP)

Lipid peroxidation index and antioxidant indicators were assessed by biochemical means in 193 healthy elderly volunteers (103 men and 90 women), ages 70-89 y and living freely in the Paris area. Lipid peroxidation index was in the same range as in young adults. Zinc, copper, and selenium levels were satisfactory and similar to those in young adults, though the range of copper values tended to be higher. Copper and selenium levels were higher in elderly women than in men. However, for selenium values this sex-related difference disappeared in elderly volunteers > 75 y. Copper-zinc-superoxide dismutase and glutathione peroxidase activities were similar to those in young adults, with no influence of sex or age. Vitamin E and total carotene, closely related to cholesterol levels, were satisfactory. Our findings show that markers of oxidative stress are not influenced by old age when good health and nutritional status are preserved, as in this selected population.

[Reference intervals and biological profile in a group of healthy elderly population in the Paris region]. / Intervalles de référence et profil biologique d'une population de sujets âgés "en bonne santé" habitant la région parisienne. (Group d'évaluation et de recherche des biologistes de l'APHP).

The superimposition of pathological processes on ageing-related metabolic changes makes the interpretation of laboratory data difficult in the elderly. Therefore, in order to establish reference values of anthropometric, hematological and biochemical variables, we have carefully selected fit, health-conscious elderly subjects on the basis of clinical and biological criteria. We observed a trend for a wider range of values than in young adults. For some variables, the values were shifted down (eg: albumin, vitamin D) or up (eg: glucose, urea, cholesterol, ferritin), as a result of slow metabolic changes or progressive functional decline of different organs. The high prevalence of hypovitaminosis D was worthy of note, particularly in women, suggesting a high risk of deficiency.

Extensive laboratory assessment of nutritional status in fit, health-conscious, elderly people living in the Paris area. Research Group on Aging.

OBJECTIVE: Nutritional status-related biological indexes were measured in fit, health-conscious elderly subjects in order to establish reference values for people over 70 years. SUBJECTS: 103 men and 90 women aged 70-89 years living freely in the Paris area volunteered to participate. METHODS: Nutritional status was assessed by anthropometric and biochemical methods. RESULTS: Serum protein and amino acid status was similar to that of young adults, with only 5.2% of the elderly subjects showing transthyretin concentrations < 0.20 g/L, as well as decreased essential amino acid levels. Iron status, assessed in terms of serum and erythrocyte ferritin levels, total iron binding capacity and erythrocyte protoporphyrin tended to be satisfactory, but iron depletion was detected in 8.8% of the subjects. Serum ferritin levels were elevated in 19.7% of the subjects. Folate and vitamin B12 status was satisfactory, while hypovitaminosis D was observed in 48.2% of cases. CONCLUSION: Our findings suggest that, in aging uncomplicated by disease, nutritional status is similar to that in younger adults, although the range of values tended to be wider, with a higher risk of certain nutrient deficiencies.

Semi-automated assay of erythrocyte Cu-Zn superoxide dismutase activity.

A semi-automated enzymatic colorimetric method for determining Cu-Zn superoxide dismutase (SOD) in erythrocytes using an FP9 parallel analyzer is described. The method is based on the reaction described by McCord and Fridovich (xanthine/xanthine oxidase, ferricytochrome C), which permits kinetic measurements to be determined colorimetrically for the assay of enzyme activity. The coefficients of variation for within- and between-run analyses were less than 6%. The limit of linearity is 3.5-times the mean value of the normal range while recovery of added SOD ranged from 91 to 120%. The method, which is both reliable and simple, allows rapid, simultaneous measurements of multiple samples.

Influence of sex and age on vitamin A and E status.

Vitamins A and E were determined in the serum of 80 free-living healthy elderly subjects and in 80 healthy younger adults. Mean values and normal ranges were established for both groups and the influence of sex and age studied. We found a significantly lower level of vitamin A in the elderly men and women and a higher level of vitamin E in elderly women, relative to their younger counterparts. These differences may be related to life-style and age-associated physiological changes and justify the use of age-corrected standard values.

Microheterogeneity of alpha 1-acid glycoprotein: variation during the menstrual cycle in healthy women, and profile in women receiving estrogen-progestogen treatment.

The concentration of alpha 1-acid glycoprotein (AGP) was measured in sera from 23 women, 14 pregnant women, 10 women receiving estrogen-progestogen treatment and 12 men. All sera were further subjected to crossed affino-immunoelectrophoresis with addition of conA in the first dimension and alpha-methylglucopyranoside in the second dimension. The distribution of AGP into three microheterogeneity forms, which were the result of this analysis, was estimated by measuring the area under the precipitation curve. The microheterogeneity patterns of AGP in the five groups were analysed from each other. An augmentation of the non reactive form is seen in women in the first part of the cycle and in women receiving estrogen-progestogen treatment compared with the three others groups. The pattern obtained in this latter group is similar to that observed in pregnant women (34 weeks) by several authors.

[Adaptation of a method for determining serum iron after deproteinization on a parallel analyzer]. / Adaptation d'une méthode de dosage du fer sérique après déprotéinisation sur analyseur parallèle.

The study of the determination of iron in sera by a bathophenanthroline method after deproteinization, has been realized according to the protocol Valtec conceived by SFBC, after adaptation on a FP9 parallel analyzer. The critical study of this adaptation included trials of within run precision (CV of 1.25%), total precision (CV 2.29 to 4.66%) as also evaluation of analytical range: the limit of linearity is 140 mumol/l. The evaluation of inaccuracy performed with patient specimens leads to establishment of follow up norms and interpretation norms of allometry line. Our whole results are in agreement with the performance standards of the protocol for the validation of methods published by the Société Française de Biologie Clinique. Finally the described method is quick acting, reliable and very inexpensive.

[Adaptation of a diazoreaction method for determining total and conjugated bilirubins on a parallel analyser]. / Adaptation d'une méthode de dosage par diazoréaction des bilirubines totale et conjuguée sur un analyseur parallèle.

A diazoreaction method of estimation of bilirubin has been adapted on a FP9 parallel analyzer. Biotrol's kit could be used only after modifications of the protocol. The critical study of this adaptation included trials of within run precision (CV 1.93 to 4.42%), total precision (CV 2.59 to 6.66%) as also evaluation of analytical range: the limit of linearity is 340 mumol/l. The evaluation of inaccuracy performed with patient specimens leads to establishment of follow-up norms and interpretation norms of allometry line. Our whole results are in conformity with the performance standards of the protocol for the validation of methods published by the Société Française de Biologie Clinique. Finally the described method is quick acting, reliable and very inexpensive.

Aminotransferases in elderly people: influence of pyridoxal 5'-phosphate addition on the determination of serum aminotransferases in healthy elderly subjects.

Aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) activity was measured in a group of 81 healthy subjects over 70 years of age and another of 180 younger persons, in order to investigate histograms and means of aminotransferase values in both groups and the variation in stimulation of these enzyme activities by pyridoxal 5'-phosphate (P5P) added in vitro. It was found that ASAT and ALAT mean values were significantly higher in both groups in the presence of P5P, than in the absence of P5P. ASAT and ALAT mean values obtained with and without P5P in old people were similar to those found in young subjects. In addition, mean stimulation percentages by P5P were identical in both groups.

[Vitamin A augmentation of the effects of chemotherapy in metastatic breast cancers after menopause. Randomized trial in 100 patients]. / Augmentation par la vitamine A des effets de la chimiothérapie dans les cancers du sein métastasés après la ménopause. Essai randomisé sur 100 malades.

Vitamin A was administered to randomly allocated patients in a group of 100 patients with metastatic breast carcinoma treated by chemotherapy. The daily doses (given indefinitely) ranged from 350,000 to 500,000 IU according to body weight. A significant increase in the complete response rate was observed. When subgroups determined by menopausal status were considered, it was observed that serum retinol levels were only significantly increased in the post-menopausal group on high dose Vitamin A. Response rates, duration of response and projected survival were only significantly increased in this subgroup. The therapeutic and biological implications of these findings are discussed.

[Biological criteria of denutrition. Search of significant parameters for diagnosis and management in surgical departments]. / Critères biologiques de la dénutrition. Recherche de paramètres significatifs pour le diagnostic et la thérapeutique en milieu chirurgical.

Assessment of the nutritional status of surgical patients with a mean weight loss of 11.5 kg included determination of the following biochemical parameters: prealbumin, retinol-binding protein (RBP), serum vitamin A and serum zinc. Patients' immunological status was investigated by delayed hypersensitivity skin tests. Prealbumin and RBP are decreased in patients. RBP levels are significantly lower than in controls: RBP therefore seems to be a better criterion of denutrition than prealbumin. Serum RBP and vitamin A concentrations are not always correlated in patients; for instance, in malabsorptions, the sharp fall in serum vitamin A is isolated. The decrease in mean serum zinc concentrations is minor. Three patients have positive skin tests with severe biochemical disturbances; only serum zinc concentrations are normal and correlated with the results of skin tests. Interpretation of investigations in surgical patients is dependent on the cause of weight loss. However, biochemical and immunological assessment of the nutritional status can demonstrate specific deficits and improve preoperative nutrition.

[Perchlorosoluble glycoproteins and myocardial infarct: modifications of the carbohydrate moiety (author's transl)]. / Glycoprotéines perchlorosolubles et infarctus du myocarde: modifications de la fraction glycannique.

Protein, hexose, amino sugar and sialic acid levels were determined in the perchlorosoluble fraction of serum from patients with myocardial infarct. Patients have significantly elevated mean values for all components. The hexose/perchlorosoluble protein and amino sugar/perchlorosoluble protein ratios were not significantly different when compared in normal and patient sera but the sialic acid/perchlorosoluble protein ratio was higher in patients with myocardial infarct. This change in sialic acid content could be related to an increased sialylation of glycoproteins normally present in serum. Particularly, an orosomucoid fraction with a higher content in sialic acid than that of the normal glycoprotein has been identified.

[Usual values of serum vitamin A using a modified fluorimetric method]. / Valeurs usuelles de la vitamine A sérique par une méthode fluorimétrique modifiée.

We report a fluorimetric technique for the determination of serum vitamin A. The critical study of this micromethod included trials of repeatability, inter-series reproducibility and an evaluation of its accuracy. It was compared with a method using high performance liquid chromatography followed by detection with UV spectrophotometry. Normal values were established for adults. The variations according to age were determined for children between the ages of 10 months and 15 years.

[Serum-ferritin assay in patients over seventy. A study on fifty-eight non anemic subjects and thirty-five anemic patients (author's transl)]. / Le dosage de la ferritine sérique chez le sujet agé de soixante-dix ans et plus. Etude portant sur cinquante-huit personnes non anémiques et trente-cinq anémiques.

An immuno-enzymatic assay of serum ferritin was performed in subjects over 70 years of age. Wide variations in serum ferritin levels were demonstrated in the non-anemic group (17-510 ng/ml). This makes interpretation of results very difficult. In anemic patients a negative correlation was found between serum ferritin levels and TIBC (Total Iron Binding Capacity). When TIBC is under 42 mumol/l or above 63 mumol/l the two values are so closely correlated that serum ferritin assay does not provide any additional information for the diagnosis of anemia. On the contrary when TIBC is between 42 and 63 mumol/l serum ferritin can allow an estimation of tissue iron storage particularly in absolute iron deficiencies.