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P Chappuis

Publications and source records attributed to P Chappuis.

At least 37 records · Page 2Linked to original sources
PubMed1993

Comparison of serum copper determination by colorimetric and atomic absorption spectrometric methods in seven different laboratories. The S.F.B.C. (Société Française de Biologie Clinique) Trace Element Group.

An interlaboratory collaborative trial was conducted on the determination of serum copper using two different methods, based on colorimetry (test combination Copper, Boehringer Mannheim, Mannheim, Germany) and flame atomic absorption spectrometry (FAAS). The general performance of the colorimetric method was below that of FAAS, except for sensitivity and linear range, as assessed by detection limit (0.44 versus 1.32 mumol/L) and upper limit of linearity (150 versus 50 mumol/L). The range of the between-run CVs and the recovery of standard additions were, respectively, 2.3-11.9% and 92-127% for the colorimetric method and 1.1-6.0% and 93-101% for the FAAS method. Interferences were minimal with both methods. The two techniques correlated satisfactorily (the correlation coefficients ranged from 0.945-0.970 among laboratories) but the colorimetric assay exhibited slightly higher results than the FAAS method. Each method was transferable among laboratories.

Analysis of Variance↗
PubMed1993

A physiological amount of zinc supplementation: effects on nutritional, lipid, and thymic status in an elderly population.

Forty-four institutionalized elderly subjects with body mass indexes (BMI) of either > or = 24 or < or = 21 participated in a 16-wk crossover study designed to determine the effects of low-dose zinc supplementation [306 mumol (20 mg)/d] on food intake, anthropometry, and biochemical and immunological indexes. Initial serum zinc concentrations were low in both groups and increased by approximately 20% after zinc supplementation. Zinc supplementation allowed a partial but significant restoration of serum thymulin activity and improved nutritional status (food intake and serum albumin and transthyretin concentrations) but had no effect on anthropometric indexes or serum apolipoproteins, except apolipoprotein CII and apolipoprotein CIII. After zinc supplementation, serum copper concentration decreased but there was no change in the ratio of low-density-lipoprotein cholesterol to high-density-lipoprotein cholesterol. Low-dose zinc supplementation allows restoration, at least partially, of nutritional and thymic status without the known disadvantages of high doses of zinc.

Aged↗
PubMed1993

Sampling conditions for biological fluids for trace elements monitoring in hospital patients: a critical approach.

Lack of coherence in the results of trace element (TE) analyses produced by various laboratories has been such as to necessitate much needed technical improvements and more detailed control over sample preparations. For too long, except for a few praiseworthy researchers, the importance of sampling conditions has been underestimated as a source of erroneous TE results. Many of the precautionary procedures for previously studied TE collection materials have proven to be so cumbersome that they cannot be applied in a hospital setting. This report deals with sampling material and conditions from a workday standpoint; a rigorous description of the contaminating roles of ambient air and routine handling of specimens places emphasis on the practical. While some metals, including cobalt, copper, iron, and selenium, present no significant risk of contamination, others, such as aluminum, cadmium, chromium, manganese, and nickel, pose quite a significant risk. They warrant attention with respect not only to the sampling itself but also the selection of the material to be used. Drawing on our hospital experience, we propose a critical approach toward the collection of samples of biological fluids (blood, urine, dialysis fluids). Needles, catheters, tubes (open and evacuated systems), and anticoagulants on the market are likewise assessed in terms of their contaminative roles. For each one elementary rules as well as realistic choices of materials and methods for a hospital environment are proposed.

Body Fluids↗
PubMed1993

[Nutritional biological markers of deficiencies of zinc, copper and selenium].

Direct and indirect indices used for the assessment of copper, zinc or selenium status in humans are reviewed. Variations, advantages and disadvantages are discussed. Despite the numerous indices, none of them provide a satisfactory assessment of the nutritional status for these trace elements. The best indices are probably serum zinc and alkaline phosphatase for the assessment of zinc status, serum selenium for the assessment of selenium status and possibly erythrocyte Cu-Zn superoxide dismutase for the assessment of copper status.

Adolescent↗
PubMed1992

A sequential and simple determination of zinc, copper and aluminium in blood samples by inductively coupled plasma atomic emission spectrometry.

A sequential method of measuring zinc, copper and aluminium in serum by inductively coupled plasma (ICP) spectrometry is described. It involves a 1/5 dilution of serum with a potassium chloride solution which enhances aluminium signal intensity and reduces variations between different matrix compositions. The method is as sensitive as atomic absorption for zinc (sensitivity: 0.11 mumol/l) and copper (sensitivity: 0.020 mumol/l) and can also be applied to monitor aluminium (sensitivity: 0.12 mumol/l) for patients receiving total nutrition therapy or hemodialysis. Its linearity extends at least to 200 mumol/l for copper and zinc and to 20 mumol/l for aluminium. The correlations with atomic absorption are satisfactory for the 3 parameters, as assessed by the correlation coefficients established for both methods. A reference interval was established with 34 sera of control subjects (19 men, 15 women) which showed an average zinc, copper and aluminium of 14.5 (S.D. 2.6), 17.3 (S.D. 2.1) and 0.32 (S.D. 0.12) mumol/l, respectively. This method does not require a simultaneous ICP spectrometer and can be performed with 1 ml of serum in a single tube, using a routine sequential ICP spectrometer.

Aluminum↗
PubMed1992

[Interlaboratory tests: completion of a method of aluminum assay in serum by electrothermal atomic absorption spectrometry].

After carrying out a prior analysis of published literature, the members of the SFBC trace-elements study group present an interlaboratory trial on the measurement of aluminum in serum using electrothermal atomic absorption spectrometry. The means of measurement chosen, following methods reliability criteria, was the use of a standard addition calibration of the samples diluted 1/5 in nitric acid 0.02 mol.l-1. Standard addition calibration was performed on two serums and gives acceptable results. Measurements are preferably carried out in 'tantalised' graphite tubes or pyrolytic tubes with platforms. However, when using graphite tubes, their quality must be checked because measurements can be seriously affected by poor quality tubes.

Aluminum↗
PubMed1992

Thymulin activity during very-low-calorie diet.

The potential use of thymulin levels as a sensitive and functional marker of energy deficiency was investigated in 13 obese women during a 3-week very-low-calorie diet. Mean weight loss was 8.92 +/- 0.52 kg after 21 days of treatment. The patients were free from infection as assessed by serum orosomucoid and C-reactive protein measurements. Serum albumin levels were not decreased throughout the experiment whereas transthyretin concentrations fell significantly during the first 2 weeks and remained fairly stable thereafter. Orosomucoid levels dropped only after 3 weeks of dieting. Serum zinc concentrations were within the normal range on admission and at the end of the experiment. Thymulin activity was not altered throughout the study, suggesting that this thymic hormone cannot be used as a functional marker of short-term energy restriction.

Adult↗
PubMed1991

Morphologic and ultrastructural effects of Maalox TC on human gastric and duodenal mucosa.

Prostaglandins (PGs) and aluminum-containing antacids (Al.AAs) are effective in preventing gastric and duodenal lesions induced by neutralizing agents. The efficacy of Al.AAs is thought to be due to neutralizing properties and to stimulation of endogenous PGs synthesis. Liquid Maalox has the same effect as cimetidine 400 mg on postprandial duodenal acid load. In numerous prospective studies, Al.AAs have been shown to be as effective as cimetidine in the short-term treatment of duodenal ulcer (DU). Maalox TC at a dosage of 3 tablets b.i.d. provides an effective method for preventing DU relapse. Its effect is similar to that of nighttime cimetidine. Meta-analysis of prospective trials suggests that Al.AAs prevent stress ulcers more effectively than does cimetidine. It has been suggested that Al.AA acts by inducing surface epithelial cell disruption. Al-induced mucosal protection could be caused by a stimulated release of endogenous PGs, induced by Al microcrystal penetration of cells. In a recent study, we showed that small amounts of Al were absorbed by human gastric mucosa and accumulated in lysosomes; however, we did not observe any histological or ultrastructural lesions of the gastric mucosa. Prostaglandins (enprostil, misoprostol, and rioprostil) are as effective as cimetidine, but less effective than ranitidine, in healing DU. Enprostil and rioprostil have been shown to be as effective as ranitidine in treating gastric ulcer (GU). Moreover, enprostil inhibits postprandial gastrin release, whereas H2-blockers increase gastrin levels. Coadministration of misoprostol with aspirin is highly effective in healing aspirin-induced gastroduodenal lesions. Moreover, cotreatment with misoprostol was associated with a marked decrease in GU in patients with osteoarthritis receiving NSAIDs chronically.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Antioxidants in female breast cancer patients.

Blood levels of selenium, zinc, copper, and vitamins E and C were measured in 48 cases and 50 controls from a hospital-based case-control study bearing on breast cancer risk factors in Montpellier (France). Cellular levels of selenium and vitamins E and C were also evaluated in most of the subjects. We found that the blood and cellular levels of these antioxidants were overall higher in cases than in controls, significantly for serum zinc, plasma, and leukocyte vitamin E. The statistical significance of the difference between case and control serum Cu crude levels disappeared after adjustment for metabolically related variables. The difference was borderline significant for leukocyte vitamin C. These results were slightly modified when vitamin pill users were excluded from case and control samples. The serum zinc odds ratios computed after adjustment for related variables were significantly elevated (2.53, confidence interval: 1.34-4.78, for the highest tertile) as were those computed previously for pooled plasma vitamin E levels in a joint study.

Adult↗
PubMed1991

[Concentration of zinc, copper, selenium and aluminium in nutritive solutions for parenteral administration].

Total parenteral nutrition (TNP) therapy is widely used. However the quantitative requirements or the toxicity of trace elements in parenteral solutions are difficult to assess. This paper deals with a study performed by the Trace Element Commission of the Société Française de Biologie Clinique. Trace metals (zinc, copper, selenium and aluminium) which are mainly involved in TPN solutions are analyzed in 12 different parenteral nutrition solutions commercially available. This multicentric assay (5 different sites of analysis) shows that a slight pollution can be noted for nearly all the solutions examined. But at this level (10 mumol/l for the most concentrated solution), the zinc intake cannot induce any toxicity. For copper and selenium the results indicated a negligible pollution. Small-volume solutions added with zinc, copper and selenium are correctly supplemented. As regard aluminium pollution, 4 solutions among 12 contain non negligible amounts of aluminium. The consequences of this TPN overload especially for young infants, indicate that the struggle against this pollution has to be strengthened.

Aluminum↗
PubMed1991

Discrepancy between anthropometry and biochemistry in the assessment of the nutritional status of the elderly.

Institutionalized aged subjects, considered free of evolutive disease and whose body weight was stable, were studied. They were divided into two groups depending on their body mass index: controls (BMI greater than or equal to 24) and depleted (BMI less than or equal to 21). The depleted group, as judged by anthropometric measurements, showed dramatically reduced body muscle and adipose masses. Usual blood parameters were normal in both groups. Biochemical markers of the protein and energy status, viz. albumin, transthyretin, transferrin, somatomedin-C, as well as serum levels of osteocalcin and apolipoproteins AI, AII, B, CII, CIII and E, were not affected in the depleted group. However, moderate iron deficiency and marked zinc deficiency were found in this group. It is concluded that in the elderly, biochemical markers of the protein and energy status are not related to the nutritional status assessed by anthropometry.

Aged↗
PubMed1989

Relationship between hair, serum and bone aluminium in hemodialyzed patients.

To establish the predictive value in osteodystrophy of hair aluminium content in patients on hemodialysis, we compared the aluminium levels in serum, cortical and trabecular bone and hair of 40 such patients with the levels in 23 healthy controls. In the patients, mean hair aluminium content was significantly higher than the controls (0.226 mumol/g, range: 0.09-0.500 mumol/g, n = 39 versus 0.126 mumol/g, range: 0.020-0.330 mumol/g, n = 49) but there was a large overlap between the two groups. The patients exhibited a significant correlation between serum and cortical bone aluminium measured by atomic absorption spectrometry (rs = 0.67, n = 37, p less than 0.05), but no correlation between aluminium in hair and in serum or bone, whether cortical or trabecular. Bone histomorphometric studies also indicated that unlike aluminium levels in cortical or trabecular bone, its levels in hair are not predictive of aluminium-induced osteomalacia. Consequently, hair aluminium cannot suitably replace bone and serum aluminium as a criterion of osteodystrophy in hemodialyzed patients.

Adult↗
PubMed1989

Association between aluminum accumulation and cardiac hypertrophy in hemodialyzed patients.

In order to investigate the possible role of aluminum accumulation on the myocardium, 50 stable asymptomatic hemodialysis patients were studied. Patient cardiac status was assessed by echocardiography. A deferroxamine (DFO) test, together with a bone biopsy, was performed to determine the magnitude of AI accumulation. Thus, an increase in serum AI after DFO (delta AI DFO) and stainable cortical bone aluminum (SCBA) were taken as parameters of AI load. Fourteen of 50 patients had no SCBA. They differed from the 36 patients with SCBA in that they had lower left ventricular mass (LVM) (P less than 0.001), increased velocity of circumferential fiber shortening (Vcf) (P less than 0.001), and higher mitral E-F slope (P less than 0.01). In the overall population there was a mild increment in serum AI and in delta AI DFO. The duration of dialysis treatment was correlated with SCBA and delta AI DFO (P less than 0.001). A correlation was observed between LVM and delta AI DFO (P less than 0.001) and between LVM and SCBA (P less than 0.001). Multivariate correlations analysis indicated that these relationships were independent of the duration of dialysis treatment. The present data suggest that, in hemodialysis patients aluminum accumulation may be associated with increased LVM.

Adult↗
PubMed1989

Deferoxamine test and bone disease in dialysis patients with mild aluminum accumulation.

Aluminum bone disease is a frequent complication of dialysis patients. The deferoxamine (DFO) test has been advocated as a noninvasive procedure for the diagnosis of AI bone lesion. However most of these studies have been performed in symptomatic patients with significant AI bone disease. Whether this test may provide similar data at an earlier stage of AI toxicity is not known. The present study evaluates prospectively 28 patients with mild AI load. Patients studied ranged in age from 21 to 65 years; duration of dialysis was 5.6 +/- 3.2 years; deferoxamine, 40 mg/kg body weight, was infused at the end of dialysis. Serum AI was measured before DFO administration and before the next dialysis treatment. Bone biopsies were performed in all patients. Cortical bone AI was determined biochemically; trabecular and cortical bone AI were also determined histochemically. Mean basal serum AI (43.2 +/- 30.8 micrograms/L) and cortical bone AI (25.7 +/- 35.2 micrograms/g) were moderately increased. Basal serum AI correlated (r = 0.77) with the increment in serum AI after DFO infusion. After DFO, stainable trabecular and cortical bone AI correlated in a similar manner with both basal serum AI and increment in serum AI. Only biochemically determined cortical bone AI was not significantly related to basal serum AI. Nineteen of the 28 patients had evidence of osteitis fibrosa on bone biopsy. Stained AI surfaces but not trabecular AI were different in patients with low and patients with high bone formation rates. The bone findings, assessed as bone formation rates and resorption surfaces, did not correlate with biochemically or histochemically determined bone AI.(ABSTRACT TRUNCATED AT 250 WORDS)

Aluminum↗
PubMed1989

[Spectrometry emission by inductively coupled plasma (SEPIHF). Application in the determination of inorganic compounds].

The authors describe the principle of inductively coupled argon plasma emission spectrometry (ICP) to determine inorganic compounds in biological samples. This method is compared with more classical electrothermal flame atomisation absorption spectrometry. The association of ICP with different instruments is reminded (HPLC, mass spectrometry, graphite furnace, hybride generation). Finally, the review ends with some applications in biological fluids.

Aluminum↗
PubMed1989

[Determination of trace elements by an assay using flameless atomic absorption spectrometry].

The authors review the keys parameters of flameless atomic absorption spectrometry trace element determination in biological medium. Contamination during sample collection and analysis are discussed. Treatments of sample are indicated. The different graphite furnaces are reviewed. Interferences and background correction are discussed. Reference samples are quoted.

Chemistry Techniques, Analytical↗
PubMed1988

Cortical v trabecular bone aluminum in dialyzed patients.

Differences among measurement of cortical and trabecular bone aluminum (AI) have been observed. Furthermore, its relationship to bone histology has been variable. In order to clarify these points, we have evaluated measurements of bone AI in relation to the source of AI and bone lesion in 25 hemodialysis patients. All patients were dialyzed in the same unit since commencement of dialysis and treated by the same physician. Age of the patients ranged from 29 to 66 years; mean duration of dialysis was 6.6 +/- 3.5 years. Dialysate water has been treated by reverse osmosis since 1980. Bone biopsy was performed in all patients after double tetracycline labeling. AI was measured biochemically in cortical bone (bCAI) and histochemically in trabecular (TAI) and cortical bone (CAI). Mean serum AI (36 +/- 21 micrograms/L) and bCAI (59 +/- 44 micrograms/g) were increased. There were significant correlations between: cortical AI and (1) serum AI (r = 0.71, p less than 0.001); (2) duration of dialysis with softened water (AI content, 55 +/- 21 micrograms/L, r = 0.65, P less than 0.001) but not with total duration of dialysis; and (3) AI ingested since commencement of dialysis (r = 0.57, P less than 0.01). Trabecular AI was not correlated with any of these parameters. None of cortical AI measurements were correlated with bone formation rates (BFR), osteoblastic surfaces (ObS), and resorption surfaces (RS) determined on trabecular bone. However, trabecular AI was inversely correlated with BFR (P less than 0.01) and ObS (P less than 0.05). Serum parathyroid hormone (PTH) was positively correlated with BFR (P less than 0.001) and RS (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗