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M Lhermitte

Publications and source records attributed to M Lhermitte.

117 records · Page 7Linked to original sources
PubMedDate not supplied

Determination by 1H NMR spectroscopy of paraquat in urine from acutely poisoned patients. Comparison with second-derivative spectroscopy method.

The application of 1H nuclear magnetic resonance (NMR) spectroscopy to characterize and quantitate paraquat in urine is described. Characterization was performed taking advantage of two NMR spectroscopy parameters: chemical shifts and coupling patterns. Without any pretreatment of the biological samples, herbicide was detected by its aromatic doublets at 8.49 and 9.02 ppm. Quantitation of the xenobiotic was realized by relative integration of the dipyridyl protons to an internal standard. After a validation step using control urine samples, quantitation was performed in urine obtained from two poisoned patients. On admission, mean paraquat concentrations were 985 (patient 1) and 500 (patient 2) micromol/L. Results are compared and found to be in good agreement, using a second-derivative spectroscopy method.

Adult↗
PubMedDate not supplied

Tetrachloroethylene and trichloroethylene fatality: case report and simple headspace SPME-capillary gas chromatographic determination in tissues.

We describe a simple, precise, and sensitive assay of tetrachloroethylene and trichloroethylene in tissues, suitable both for emergency cases and forensic medicine. The method employs headspace solid phase microextraction-capillary gas chromatography and electron capture detection. The case is relative to a 45-year-old woman discovered unconscious in a laundry area. The concentrations of the solvents in tissues were determined and compared to other previously published fatalities.

Chromatography, Gas↗
PubMedDate not supplied

1H NMR spectroscopic investigation of serum and urine in a case of acute tetrahydrofuran poisoning.

This article reports the investigation by 1H nuclear magnetic resonance (1H NMR) spectroscopy of biological fluids in a case of intentional poisoning with tetrahydrofuran (THF). Occupational exposures to this solvent are well documented, but acute poisoning cases are extremely rare, and the one presented here is the second known case of this kind. Urine and serum samples were collected. Without any pretreatment, the presence of THF was confirmed by characteristic resonances at 1.90 and 3.76 ppm; high lactate levels were also observed. The presence of gamma-hydroxybutyric acid (GHB) was noted. Quantitative analysis was performed by relative integration of peak areas. THF concentrations were 813 and 850 mg/L (11.3 and 11.8 mmol/L), and GHB concentrations 239 and 2,977 mg/L (2.3 and 28.6 mmol/L) in serum and urine, respectively. A gas chromatographic-mass spectrometric method confirmed 1H NMR observations. The origin of GHB detected in serum and urine is also discussed.

Acute Disease↗
PubMedDate not supplied

[Polymorphism and glycoprotein character of Ricinus communis lectins purified by affinity chromatography].

Two lectin fractions (S20W = 6,8 and 4,9 S) were purified from Ricinus communis seeds. The purification was carried out in four steps : ammonium sulfate fractionation, affinity chromatography on Sepharose 4 B, gel filtration on Sephadex G 150 and chromatography on CM celluloes. The purified lectins were glycoproteins whose chemical composition was determined. Amino terminal analysis of the two fractions revealed glycine and serine. Polyacrylamide gel electrophoresis of the higher molecular weight fraction allowed the separation of several components with different affinity for PAS staining.

ABO Blood-Group System↗
PubMedDate not supplied

[Cannabis and nifluril].

Explore the source record for details and available documents.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMedDate not supplied

[Biomarkers for toxicity and metabolic abnormalities of the main severe poisonings. Clinical and toxicologic symptoms. Conservative determination].

The members of the joint group "Toxicology and Clinical Biology" of the French Society of Clinical Biology (SFBC), the French Society of Analytical Toxicology (SFTA), and the Society of Clinical Toxicology (STC), suggest guidelines to meet the requirements of clinical biologists who are not specialized in toxicology. Based on good laboratory practice they propose a number of guidelines. Three synthetic tables have been established. They are not only toxicity biomarkers and metabolic disorders associated with the main severe intoxications, but also clinical signs that are observed during these intoxications, finally biological sampling as a precautionary measure. The table also takes into account approximately fifty xenobiotics: main clinical signs emergency, identification or quantification of the suspected product, useful biological markers, therapeutic, quantitations necessary to take into consideration patient care, and poison antidotes, are described. Recommendations regarding medical and forensic techniques are also proposed by the group. It is also necessary to collect and store biological samples when the individual patients are in charge. These samples will be analyzed or not depending on the individual case history.

Biomarkers↗
PubMedDate not supplied

Mexiletine metabolism in vitro by human liver.

Human livers were used in investigations of mexiletine biotransformation in vitro. The major metabolic pathways of mexiletine oxidation, to form hydroxymethylmexiletine (HMM) and p-hydroxymexiletine (PHM), were characterized in liver cell preparations. The localization of reactions in the microsomal fraction, their heat lability, NADPH requirement and inhibition by prototype cytochrome P-450 (P-450) inhibitors (CO, SKF 525-A, metyrapone and quinidine) implied that they were catalyzed by P-450. Kinetic studies of reactions were performed in microsomes from five different livers. Eadie-Hofstee plots of data gave no indication of systematic deviation from linearity, suggesting that over the range of mexiletine concentrations examined (3.3-133.3 microM), HMM and PHM were formed by a single enzymatic site. Within a liver preparation, Km and Vmax values for HMM and PHM formation were similar. Between livers, Km values of reactions were similar with only a 1.8-fold range for each reaction, whereas Vmax values showed 7.2- and 7.8-fold ranges for HMM and PHM production, respectively. There was a very strong correlation between Vmax values for both reactions. These results, coupled with a parallel effect of inhibitors (SKF-525A, metyrapone, alpha-naphtoflavone and quinidine) on HMM and PHM formation, argue that both reactions are mediated by a common P-450 or closely related isozymes. In addition, the present in vitro results support the hypothesis that the genetically variable P-450 db 1 isozyme catalyzes the oxidation of mexiletine.

Biotransformation↗
PubMedDate not supplied

[Comparative study of bronchial mucins isolated from the sputum of patients suffering from cystic fibrosis or other chronic bronchial diseases (author's transl)].

Most of the mucins isolated from the sputum of patients suffering from cystic fibrosis are acidic. Acidic mucins from a child suffering from cystic fibrosis were degraded by alkali treatment. Analysis of the degradation products demonstrated the wide heterogeneity of the carbohydrate chains linked to the mucin polypeptide moiety. However, this heterogeneity of carbohydrate chains is probably not restricted to mucins from patients with cystic fibrosis. Bronchial mucins were prepared either from the sputum of different patients belonging to blood group O or B and suffering from cystic fibrosis, chronic bronchitis and other chronic bronchial diseases, or from bronchial washings performed in macroscopically healthy area of the bronchial tree of subjects belonging to blood group O. The chemical composition of each mucin fraction was established and an average carbohydrate chain length was estimated. Acidic mucins isolated from the sputum of two children suffering from cystic fibrosis were more sulfated than sialylated and their average carbohydrate chain length was relatively large. These characters were not specific for cystic fibrosis since they were also found in acidic mucins of two children suffering from other bronchial diseases. Most of the acidic mucins isolated from the sputum of three adults suffering from chronic bronchitis were more sialylated than sulfated and had a relatively short average carbohydrate chain length. The sputum of these patients also contained a variable proportion of neural or weakly acidic mucins. The mucins isolated from bronchial washings performed in macroscopically healthy areas of the bronchial tree were acidic molecules whose acidic characteristics and average carbohydrate chain length were about the same as for acidic mucins from patients with chronic bronchitis.

Adult↗