An evaluation of the biological significance of aluminium in plasma and hair of patients on long-term hemodialysis.

In hemodialyzed patients, the risk of toxicity attributed to the body accumulation of aluminium (Al) justifies the need for monitoring Al in various human media. In this study, Al concentrations in the hair and plasma of 78 hemodialyzed patients with chronic renal failure and of 351 healthy volunteers were measured by electrothermal atomic absorption spectrometry with Zeeman effect. Plasma Al concentrations in patients were significantly higher than in the controls and positively correlated with time on dialysis. Hair Al levels were widely distributed with no significant distinction between patients and controls. On the subject of establishing correlation, the authors stress the importance of taking into account the kinetics of the elimination of minerals from hair. Even when this was done, in the patient group there was no statistical link between plasma and hair Al levels. Hair Al analysis is of no value as an indicator of body Al accumulation.

Determination of total mercury in human hair samples by cold vapor atomic absorption spectrometry.

A procedure for the determination of mercury in human hair by cold-vapor atomic absorption spectrometry with a new reaction vessel was developed and evaluated. To eliminate the so-called matrix effect, calibration was carried out in an isomedium under identical operating conditions. Under these conditions, the recovery percentage of mercury from human hair digest samples using the peak height method, was 102 +/- 2.2%. The method has been used for measuring the mercury level in hair of different groups of people living in the Nantes, France area.

["Medicolegal" bone fluorosis. Apropos of 2 cases of possible criminal poisoning]. / Fluorose osseuse "médico-légale". A propos de deux cas de probable intoxication criminelle.

We report two cases of skeletal fluorosis in two men, 55 and 69 year-old. The physical findings and the roentgenograms were typical and chemical analysis confirmed the diagnosis. Surprisingly, fluoride concentrations in blood and urine were increased at the beginning of the hospitalizations and lower during the hospitalizations. The origin of fluor intake remained unknown, leading to consider a possible criminal poisoning. Then, we discuss the attitude of physician in a case a possible criminal poisoning: denunce the crime to the police or not, as regards french law.

[Household cleansers and nickel allergies]. / Allergie aux détergents et allergie au nickel.

Attention of authors has been drawn by the observation of patients presenting a nickel-dermatosis, instigating by the touch of jewelry (ear-rings, bracelets, necklaces...) and also a sensitization for housework cleansing agents. The chemical analysis of numerous housework cleansing agents exhibited the constant presence of nickel in these housework cleansings. These investigations enable the authors to affirm a close relationship between sensitization for nickel and sensitization for housework cleansings. Some patients present also sensitization for chromium or cobalt. The authors think this polysensitization is induced by metal's contamination.

[Changes in cutaneous zinc during skin aging]. / Evolution du zinc cutané au cours du vieillissement cutané.

Variations of epidermal zinc concentration with aging were studied by measuring zinc levels in the epidermis of two groups of healthy subjects: group A aged less than 35 years; group B aged more than 65 years. The epidermis was obtained from a suction blister, and zinc levels measurements were performed by absorption spectrophotometry. There was a significant decrease (p less than 0.01) of epidermal zinc concentration with aging, and zinc contents of the epidermis were the same in men and women. On the other hand, no significant difference was found in zinc blister fluid levels between the two groups, confirming the absence of relationship between plasma zinc and epidermal zinc. The decrease of epidermal zinc concentrations observed in elderly subjects might be due to a decrease of enzyme activities in the epidermis induced by aging; conversely, a low epidermal zinc level might induce, by itself, a fall in enzyme activities. Thus, zinc might play an important role in the development of alterations in keratinocytes with aging.

[A simple and rapid method for blood gas extraction for the measurement of carbon monoxide by infrared spectrometry (author's transl)]. / Procédé simple et rapide pour l'extraction des gaz du sang en vue du dosage du monoxyde de carbone par spectrométrie infrarouge.

Carbon monoxide is extracted along with other blood gases, in a plexiglass syringe, at room temperature, by vacuum in the presence of phosphoric acid. The gases liberated are transferred to another plexiglass syringe where they are diluted with air. The carbon monoxide content of this gazeous mixture is determined by infrared spectrometry. This simple and rapid extraction procedure provides reliable results and is performed with robust equipment which is easy to clean and maintain.

Zinc salts effects on granulocyte zinc concentration and chemotaxis in acne patients.

To explore the mechanism by which zinc acts on cutaneous inflammatory lesions, we studied granulocyte zinc levels and in vitro polymorphonuclear leukocyte chemotaxis in 20 acne patients before and after 2 months of zinc therapy (200 mg/day zinc gluconate). The zinc level was assayed by flame absorption spectrophotometry and chemotaxis was performed by agarose assay. After 2 months of treatment, a significant decrease in granulocyte zinc level associated with inhibition of chemotaxis (r = 0.69) was observed in 16 patients. This suggests that zinc anti-inflammatory action is related to inhibition of polymorphonuclear leukocyte chemotaxis induced by a decreased granulocyte zinc level.

[In vitro dissolution of metallic oxides in human plasma and binding of metals to plasma proteins--effect of chelators]. / Dissolution in vitro des oxydes métalliques dans le plasma humain et fixation des métaux sur les protélnes plasmatiques--influence des chelateurs.

The solubility in biological liquids of oxides is one of the factors which determinate the speed of penetration into the blood stream of toxic agents contained in solid particles inside pulmonary alveoli. This solubility was studied in vitro for the six following metal oxides: Cd, Cr, Fe, Mn, Pb, Zn, by holding particle oxides in suspension into human plasma at 37 degrees C, during variable time. The experimentation was realized on particles which belong to two categories which sizes are 0.45-2 and 2-5 mu. The evolution of metal oxide dissolved level according to time have enabled exponential relation parameters to be calculated. These parameters translate the particle oxide dissolution into plasma and have permitted to classify metal oxide in decreasing solubility order: Cd, Zn, PbO, Fe2O3, Fe3O4, Mn, PbO2, Pb3O4 and Cr2O3. The second part of the experimentation is about dissolved metal distribution between the different protein fractions. Dissolved metal is distributed between diffusible metal (lower than 10 per cent) and metal binding proteins chiefly in albumin except for Fe which is bound to transferrin. Chelating agents into plasma reduce the proportion of metals bound to proteins. EDTA Ca is energetic on all metals mainly on Lead, Cadmium, and Zinc. N-acetyl-DL penicillamin is less energetic. Meso 2,3 dimercapto succinic acid, and 2,3 dimercapto-1-propan sulfonic acid have an effect only on Lead but in a very light way. Desferrioxamin release a great proportion of Iron bound to proteins. These results, obtained in vitro, are similar to those from animal experimentation or those observed in human therapeutic.

[Kinetics of the in vitro dissolution of cadmium oxide particles in human plasma and cadmium binding to plasma proteins--effect of chelating agents]. / Cinétique de la dissolution in vitro des particules d'oxyde de cadmium dans le plasma humain et fixation du cadmium sur les protéines plasmatiques--influence des chelateurs.

The solubility in biological liquids of particles which penetrate as far as alveolar compartment, has a determinant influence on their absorption into the blood stream. The experiments conducted in vitro have enabled cadmium oxide dissolution parameters in human plasma at 37 degrees C to be calculated, as well as cadmium dissolved concentration according to time and cadmium particle level, initial dissolution rate and dissolved cadmium concentration at saturation. The smaller the particles, the quicker they dissolve. Dissolved cadmium is distributed between diffusible cadmium (2%) and cadmium binding proteins (98%) chiefly in albumin and IgA. The cadmium binding protein fraction can be mobilized by chelating agents. In vitro studies allow the determination of mobilized cadmium fraction according to time. The calco sodic salt of ethylen diaminotetraacetic acid and N-acetyl-DL penicillamine are the most energetic compounds, compared to meso 2,3 dimercaptosuccinic acid, and 2,3 dimercapto-1-propan sulfonic acid.

[The relationship between the course of bismuth encephalopathy and the amount of bismuth in blood and urine]. / Relations entre l'évolution des encéphalopathies bismuthiques et les taux de bismuth dans le sang et dans les urines

Study of the course of bismuth encephalopathy following the ingestion of a bismuth salt in relation to blood and urinary bismuth levels indicates a close parallel between the improvement in the clinical picture and the decrease in the degree of toxic impregnation of the body. This confirms the direct responsibility of bismuth for the disorder. Regression of myocolonic movements goes with the fall in blood bismuth levels, whilst improvement in the confusional syndrome is aomewhat delayed. There is a significant correlation between bismuth levels in the blood and urine. The excretion of bismuth is slow, and the persistence of blood and urinary bismuth levels higher than normal for several weeks after the acute phases and the interruption of the ingestion of bismuth salts reflects the existence of stable bonds between the metal and cellular constituents. The authors have observed a non-negligeable solubility of bismuth sub-nitrate in certain drinking waters, which brings up the hypothesis of a possible role of the hydrosobulity of bismuth in the pathogenesis of the intoxication.

[Change in the plasma and urine levels of ionized fluorine under the influence of low doses of niflumic acid. Possible application to the treatment of osteoporosis]. / Variations des taux de fluor ionisé plasmatique et urinaire sous l'influence de faibles doses d'acide niflumique. Application éventuelle au traitement de l'ostéoporose.

Following several series of tests, it was shown that the administration of 500 mg/day of niflumic acid, at a dose of 250 mg morning and evening, causes in subjects with a weight between 65 and 75 kilos a moderate but permanent and relatively stable rise in the levels of plasma ionised fluorine. This constant concentration of ionised fluorine in the plasma contrasted with the marked and rapid variations which follow the ingestion of sodium fluoride, which is usually prescribed in the treatment of osteoporosis. This may explain why the fluoride ion is more active on osteogenesis when it is liberated in the organism from niflumic acid by way of metabolic processes. The dosage of 500 mg daily is much less than that which produces fluorosis after prolonged treatment; it suggests a trial of niflumic acid in the treatment of osteoporosis, respecting naturally the contra-indications, and supervising the digestive tract as always with anti-inflammatory drugs.

Hematological findings among styrene-exposed workers in the reinforced plastics industry.

A cross-sectional survey of hematological parameters was carried out among 221 workers exposed to styrene in the reinforced plastics industry and 104 controls. Styrene exposure was assessed in both groups by monitoring urinary excretion of styrene metabolites (i.e. mandelic and phenylglyoxylic acids) in post-shift urinary samples collected over five consecutive days. Blood tests were performed with the same counter for all subjects. Information on factors liable to affect hematological parameters was collected from personal questionnaires completed by the workers. Urinary excretion of styrene metabolites varied from 15 to 3740 mg/g creatinine. Exposed subjects exhibited significantly lower mean values of neutrophils and mean corpuscular hemoglobin concentration (MCHC) than controls, and significantly higher mean values for monocytes and mean corpuscular volume. A dose-effect relationship was found for MCHC which decreased with urinary metabolite concentrations. These results remained statistically significant for all parameters after adjustment for age, sex, tobacco and alcohol consumption, place of residence (rural or urban) and time of blood sampling (morning or afternoon) with the exception of neutrophils whose relationship with exposure was essentially explained by smoking. These results are suggestive of a direct effect of styrene-exposure--in the range considered--on the statistical distribution of some hematological parameters.

Serum selenium in melanoma and epidermotropic cutaneous T-cell lymphoma.

As several studies have demonstrated a relationship between decreased serum selenium concentrations and the frequency of certain cancers, we studied these concentrations in two kinds of cutaneous tumour cancer: melanoma and epidermotropic cutaneous lymphoma. We first determined the predictive value of the selenium assay for the frequency of recurrences in stage I and II melanomas and then considered the relationship between serum selenium concentrations before treatment and therapeutic response. Two hundred melanomas (81 stage I, 63 stage II, 56 stage III) and 51 epidermotropic cutaneous T-cell lymphomas (CTCL) (8 stage I, 24 stage II, 10 stage III, 9 stage IV) were included in the study. Selenium assays were performed by atomic absorption spectrophotometry (92 +/- 16 micrograms/l in 30 normal subjects). Our study showed decreased serum selenium concentrations for melanoma (81 +/- 27 micrograms/l) and lymphoma (78 +/- 36 micrograms/l) relative to disease severity. The concentration was significantly lower (76 +/- 22) for stage I and II melanomas with recurrence within 2 years (31 patients), compared to those without recurrence (113 patients) (p < 0.05). Before treatment, it was higher in CTCL with good response to treatment (89 +/- 36) than in those without response (62 +/- 30) (p < 0.01). This study thus demonstrates the prognostic value of selenium assays in the follow-up of melanoma and CTCL.

Plasma zinc is decreased only in generalized pustular psoriasis.

Plasma and cutaneous zinc were studied in 22 psoriatic patients and 14 controls. The psoriatics were divided into three groups: 10 extensive psoriasis vulgaris, 5 palmoplantar psoriasis and 7 extensive pustular psoriasis. Low plasma zinc and decreased in vitro chemotaxis of polymorphonuclear leukocytes were found only in extensive pustular psoriasis, whereas zinc was not decreased but rather elevated in skin. This explains why conflicting results on plasma zinc have been previously reported in psoriasis and confirms that cutaneous zinc depletion is not a feature of psoriasis.