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Biomedical subjects

J Arnaud

Publications and source records attributed to J Arnaud.

At least 127 records · Page 7Linked to original sources
PubMed1990

Determination of the major zinc fractions in human serum by ultrafiltration.

In this paper we report a method for measuring ultrafiltrable zinc in human serum by electrothermal atomic absorption spectrophotometry. We show also that ultrafiltration permits to determine alpha-2-macroglobulin bound zinc and loosely bound zinc if a strong zinc ligand (EDTA) is added to serum before ultrafiltration. This last fraction, after deduction of ultrafiltrable zinc, represents roughly all albumin bound zinc. In 20 controls we found that ultrafiltrable zinc amounted 0.311 mumol/L (S.D. = 0.117 mumol/L), alpha-2 macroglobulin bound zinc 3.08 mumol/L (S.D. = 0.221 mumol/L), and albumin bound zinc 12.11 mumol/L (S.D. = 1.95 mumol/L). Our method needs only a small volume of serum, it is simple and rapid but also very accurate and reliable. The loosely bound fraction is very dynamic and, representing the physiologically active part of serum zinc, it could be a good marker of zinc deficiency.

Biomarkers↗
PubMed1990

Analysis of HLA-DP in HLA-DR/GLO recombinant families and in the population of south-western France.

The existing estimates of the recombination fraction between DR and DP are quite variable and often based on anecdotal observations. We have estimated the DR/DP crossover frequency on the basis of families typed for HLA markers and GLO. The frequency of DR/GLO crossing over was 8.7% (23/264 informative meioses), maternal recombinations being about twice as frequent as paternal ones. Of 17 DR/GLO recombinant families typed for DPw1-6, DP was informative in 11 (13 recombinations) but only one of these gave rise to a DR/DP crossover. According to these data the DR/DP recombination fraction is below 1%, in contrast to some earlier published materials. HLA-DR/DP haplotypic associations on 127 informative Caucasoid haplotypes have been evaluated. In agreement with previous studies, DR3 was positively associated with DPw1 and, in addition, DR7 was found to be positively associated with DP-blank (not DPw1-6). The rare DPw6 allele is possibly associated with the DR4, Dw14 allele. The DR-DP haplotype profiles suggest other associations which might become significant if larger materials are tested. The frequency of DP alleles in a random material (N = 201) was found to be in accordance with most of the previously published frequences on European Caucasoids with DPw4 as the predominating frequency (gene frequency 40%) and a blank frequency of 27%.

Alleles↗
PubMed1990

[Interlaboratory serum copper-zinc comparisons. Analytical performance during the first year].

In 1988 the Trace Elements Commission of the French Society for Clinical Biology operated an interlaboratory comparison program for copper and zinc determination in serum. The main objective is to enable participants to maintain or improve the accuracy of their analytical performance by comparing their results periodically, on the basis of three criteria: comparison of the results with the mean value, accuracy (recovery of copper and zinc additions), between-run reproducibility for identical samples. The statistical methods for evaluation are reported in detail. After one year, the results show a regular improvement in their homogeneity, especially for copper, indicating that the participants have taken into account their results to improve their analytical performance. The recovery of the copper and zinc additions shown a considerable improvement of their homogeneity. The coefficients of variation improved from 30 to 21 p. cent for copper and from 29 to 15 p. cent for zinc. The between-run reproducibility for identical samples was also evaluated. A performance score for each participant was calculated for each evaluation criteria, and a global score was attributed. The procedure for individual and global evaluation was reported in detail. The best scores were obtained for accuracy and the worst for the comparison with the mean value. The participants were considered "good", "acceptable" or "inadequate" in view of their global scores. The global performance was compared to other international interlaboratory comparison programs for copper and zinc in serum.

Copper↗
PubMed1989

Human red-cell acid phosphatase (ACP1): a new mutant (ACP1*KUK) detected by isoelectric focusing, kinetics of thermostability and substrate activity.

A new rare mutant of the red-cell acid phosphatase (ACP1) is described using conventional gel electrophoresis and isoelectric focusing migration. According to the electrophoretic patterns obtained, the new mutant ACP1* KUK is different from the ACP* H and ACP1* A' variants already described. The enzyme activities and the thermostability curves definitively confirm the existence of a new variant. The transmission of this mutant was followed through a pedigree of three generations. The family originated from Czechoslovakia. The frequency of the variant is probably less than 0.001.

Acid Phosphatase↗
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↗
PubMed1989

[Short- (1 session) and long-term (6 months) course of the serum level of zinc in 33 hemodialysis patients].

In patients with chronic renal insufficiency undergoing hemodialysis, the seric zinc level was significantly lower than in normal subjects. In 7 patients this was even more marked prior to their first hemodialysis session. Following hemodialysis this level increased, but by comparing the zinc level to that of the binding proteins it could be seen that this result was a reflection of the hemo-concentration phenomenon. During hemodialysis there was no change in the zinc level of dialysate. Finally, a significant increase in the seric level of the 7 new patients was noted after 6 months of hemodialysis treatment. This increase reached the mean level observed in the 26 other patients who had been undergoing hemodialysis from between 8 and 87 months, but pre-dialysis normalization of seric zinc levels was not attained. The reasons for this increase in the 7 recently hemodialysed patients receiving no zinc treatment are discussed.

Female↗
PubMed1988

[Levels of manganese in biological media: value, samplings, physiopathological variations. Bibliographic review].

The great diversity of methods for manganese analysis in biological materials (serum, plasma, whole blood, urine, spinal fluid and hair) reveals the difficulty in measuring extremely small quantities of this element. An examination of these methods demonstrate that the most used one is flameless atomic absorption spectrometry. This review offers a comparison of the different instrument settings. Authors' recommendations for the collecting of samples are reported in detail. A description of the preliminary steps, the handling of the specimen samples, the preparation of the standards, procedures used, analytical criteria and perturbations is also included. Normal values and their physiological and pathological variations are also described.

Body Fluids↗
PubMed1988

Population polymorphism of the GLO1 enzyme. Identification of two new variants.

A new electrophoretic technique for the determination of the glyoxalase I (GLO1) polymorphism on mixed agarose and starch gel is applied to the genetic study of "Provinces Françaises" and some other human populations. Four rare electrophoretic variants are revealed; two of them (GLO1*4, GLO1*5), both new, are discussed. In the "Provinces Françaises" the mating GLO1 2-1 x GLO1 2-1 shows an irregular segregation of the GLO1 alloenzymes.

Africa, Western↗
PubMed1988

Determination of manganese in biological materials by electrothermal atomic absorption spectrometry: a review.

The great diversity of methods for measuring manganese in biological materials (serum, plasma, whole blood, urine, spinal fluid, and hair) reflects the difficulty in measuring extremely small quantities of this element. Detailed examination of these methods demonstrates that the one most used is flameless atomic absorption spectrometry. In this review we report the different instrument settings for wavelength, slit width, protection gases, graphite furnaces, type of background correction, amounts measured, and thermal programs. We give detailed recommendations by various authors for collecting samples. A thorough description of the preliminary steps and the handling of the specimen samples is also included: direct determination with or without dilution, addition of a matrix modifier or determination after ashing, with or without chelation-extraction steps. The preparation of the standards, procedures used, analytical criteria (accuracy, precision, specificity, detection limit, linearity), problems (interferences, matrix effects), and reference values and their physiological variations are also described. We give a consensus of recommendations concerning the choice of a method.

Female↗
PubMed1988

An international quality-assessment program for measurement of aluminum in human plasma: a progress report.

In view of the increasing interest in measurement of aluminum in plasma of hemodialysis patients and the analytical difficulties, which may lead to false clinical interpretations, we organized an international interlaboratory quality-control program that has operated since 1983. The results obtained after four years (72 participants) demonstrate a lessened discrepancy of the results. This program allowed some laboratories to improve their results and even to solve some of their analytical problems. This surveillance will be continued and extended to include the analysis of dialysis fluids.

Aluminum↗
PubMed1987

[Serum and tissue concentrations of zinc after oral supplementation in chronic alcoholics with or without cirrhosis].

Seric and hepatic zinc concentrations are decreased in chronic alcoholics, particularly those with cirrhosis. The purpose of this study was: 1) to assess the duration of zinc intake necessary to normalize seric and hepatic zinc concentrations; 2) to demonstrate that this supplementation did not increase zinc concentrations in other tissues (erythrocytes, leukocytes and hair) and did not induce adverse reactions. Twenty alcoholic patients with (group A: n = 13 or without (group B: n = 7) cirrhosis received zinc sulfate 600 mg daily during 10 days, 10 patients with alcoholic cirrhosis during 30 days (group C) and 7 during 60 days (group D) and were compared with a group of 30 normal subjects. Serum zinc concentrations increased to normal values in all groups of patients. Hepatic zinc increased significantly in groups B (p less than 0.05) and D (p less than 0.01). Zinc concentrations in erythrocytes, leukocytes and hair were unchanged. No adverse reactions were observed. We conclude that seric zinc concentrations reached normal values in alcoholics with or without cirrhosis by daily supplementation of 600 mg zinc sulfate during 10 days to 2 months while hepatic zinc concentrations increased but remained under normal values in some patients, particularly those with cirrhosis.

Administration, Oral↗
PubMed1986

[Serum trace elements and myocardial infarction].

The authors report trace elements concentrations (zinc, nickel, selenium, copper, manganese and chromium) during myocardial infarction described in some publication. Serum zinc decreases during the first two days after acute myocardial infarction and returns to normal level in two weeks. Serum nickel increases during the first 36 hours and copper during the first four days. The different explanations of these disturbances are also exposed.

Aspartate Aminotransferases↗
PubMed1986

[Methods of determination of selenium in biological matter].

Main techniques used: graphite furnace atomic absorption direct or after preliminary treatment of the sample, graphite furnace atomic absorption by generation of hydrides, fluorometry, gaz chromatography, differential pulse voltammetry. The various quality criteria of these methods are compared as well as the usual values in the different biological fluids (whole blood, plasma, serum, erythrocytes, urine).

Chromatography, Gas↗