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PubMed2003

Fatal acute poisoning by bentazon.

A case of fatal suicidal bentazon poisoning is presented along with a description of the different analytical methods involved. A 56-year-old farmer was examined by the family doctor 1 h after voluntarily ingesting 500 mL of FIGHTER (bentazon, 480 g/L water). He presented a Glasgow score of 15, polypnea, diarrhea, and vomiting. During transport by ambulance to the hospital, he tossed, sweated, and suddenly presented breathing difficulty followed by heart failure. Tracheal intubation was impossible (H1.5) despite use of different diameter cannulas because of extreme general muscle rigidity. All attempts at resuscitation failed, and the patient died within 2 h postingestion. Blood and urine samples were taken just before death. General basic and neutral drug screening by high-performance liquid chromatography-diode-array detection and gas chromatography-nitrogen-phosphorus detection showed no strychnine or other drugs or toxics except for citalopram (< 0.1 mg/L) and bentazon, but this weak acidic molecule (pKa3.3) was badly extracted in alkaline conditions. Plasma and urine levels, measured after acidic extraction, protein precipitation, or simple dilution, were 1500 and 1000 mg/L, respectively. Bentazon (M.W. 240) was confirmed by its basic mass spectrum (ESI-, m/z 239, 197, 175, 132) or by that of methylated derivative (El+, m/z 254, 212, 175). An hydroxylated metabolite (ESI-, m/z 255, 213, 191, 148; El+, m/z 284, 242, 163) and the N1-glucuronide conjugate of bentazon (ESI-, m/z 415, 239) were also detected in urine. (Quantitation ions are underlined.) This first case of bentazon poisoning with available analytical data revealed the high toxicity of this compound after large dose ingestion with early and heavy symptoms such as muscle rigidity probably related to muscular toxicity. Comparison with another nonfatal case and with toxicological data on animals is discussed.

Benzothiadiazines↗
PubMedDate not supplied

Gas chromatography-chemical ionization mass spectrometry of cocaine and its metabolites in biological fluids.

A gas chromatographic-chemical ionization mass spectrometric (GC-CIMS) method is described for the determination of cocaine, benzoylecgonine, and norcocaine. The procedure uses stable isotopes as internal standards and a mixture of methane-ammonia as chemical ionization reagent gas. Run-to-run and within-run coefficients of variation (%) are less than 10% and the method has a sensitivity of less than 5 ng/mL from 1 mL or 1 gram of sample. The procedure has been applied to a number of cases involving cocaine intoxication and analytical data from these are described.

Body Fluids↗
PubMed1975

Selenium content of food consumed by Canadians.

Four composite diets from three cities, each representing the daily per capita consumption of foods in Canada, contained on analysis 191, 220, 113, and 150 mug selenium. Cereals provided the most selenium (62-112 mug) followed by meat, poultry, and fish (25-90 mug) and dairy products (5-25 mug). The average daily intake of selenium in Canada was also calculated from published analytical data and the per capita disappearance of unprepared foods. The total intake was 197 mug/day, and the major sources were wheat flour (98 mug), pork (21 mug), poultry products (24 mug), and fish (17 mug). Because the average diet is rich in selenium, the possibility of a deficiency in the adult is considered to be remote. Milk is relatively low in selenium, and thus the greatest deprivation in humans would occur during infancy.

Adult↗
PubMed2005

Differential improvement among countries in child stunting is associated with long-term development and specific interventions.

Stunting represents growth failure resulting from poor nutrition and health during the pre- and postnatal periods. Initiatives since 1980 have steadily reduced malnutrition and consequent retardation of child growth, but 1 of 3 preschool children worldwide remains stunted. Countries have varied substantially in progress achieved in reducing stunting. This study aimed to understand which underlying (i.e., proximal) and basic (i.e., distal) national factors have been most important in explaining this variation among countries, and the relation between the 2 sets of factors. Eighty-five developing countries with at least 2 surveys for stunting >4 y apart were included from the WHO Global Database on Child Growth. The analytic data set with independent variables from several sources was constructed to match closely by year for each country to initial and final stunting data. Full-information maximum likelihood estimated multiple linear regression models while accounting for missing data in independent variables. The final model explained 65.5% of the variance of change in stunting, and included both underlying and basic variables: initial and change in immunization rate, initial and change in safe water rate, initial female literacy rate, initial government consumption, initial income distribution, and the initial proportion of the economy devoted to agriculture. Although factors that were important for reducing stunting in the past may not necessarily be the ones that are important in the future, these results suggest that it possible for substantial progress to be made in reducing the current high prevalence of stunting by investing in both long-term development and in specific interventions.

Agriculture↗
PubMed2004

Metabolite fingerprinting and profiling in plants using NMR.

Although less sensitive than mass spectrometry (MS), nuclear magnetic resonance (NMR) spectroscopy provides a powerful complementary technique for the identification and quantitative analysis of plant metabolites either in vivo or in tissue extracts. In one approach, metabolite fingerprinting, multivariate analysis of unassigned 1H NMR spectra is used to compare the overall metabolic composition of wild-type, mutant, and transgenic plant material, and to assess the impact of stress conditions on the plant metabolome. Metabolite fingerprinting by NMR is a fast, convenient, and effective tool for discriminating between groups of related samples and it identifies the most important regions of the spectrum for further analysis. In a second approach, metabolite profiling, the 1H NMR spectra of tissue extracts are assigned, a process that typically identifies 20-40 metabolites in an unfractionated extract. These profiles may also be used to compare groups of samples, and significant differences in metabolite concentrations provide the basis for hypotheses on the underlying causes for the observed segregation of the groups. Both approaches generate a metabolic phenotype for a plant, based on a system-wide but incomplete analysis of the plant metabolome. However, a review of the literature suggests that the emphasis so far has been on the accumulation of analytical data and sample classification, and that the potential of 1H NMR spectroscopy as a tool for probing the operation of metabolic networks, or as a functional genomics tool for identifying gene function, is largely untapped.

Biochemistry↗
PubMed1989

Synthesis and evaluation of some novel phosphate and phosphinate derivatives of araA. Studies on the mechanism of action of phosphate triesters.

A number of novel phosphinate and phosphate triester derivatives of the anti-viral nucleoside analogue araA have been prepared. Spectroscopic and analytical data have been collected on both the reagents and the nucleotides. An in vitro assay indicated inhibition of DNA synthesis by mammalian cells, by each of the nucleotide derivatives, in the range 3-30 microM. Inhibition was reduced, but not abolished, for the phosphinates relative to the phosphates. These results are consistent with a mode of action involving release of the free nucleoside araA and the nucleotide araAMP.

Animals↗
PubMed1975

Specificity of deoxyribonucleic acid transmethylase induced by bacteriophage T2. I. Nucleotide sequences isolated from tmicrococcus luteus DNA methylated in vitro.

(Deoxyribonucleic acid from Micrococcus luteus was methylated in vitro in the presence of S-adenosyl-(14C methyl)methionine with a DNA methyltransferase purified from extracts of te. coli infected with bacteriophage T2. The labelled DNA was degraded by enzymatic and specific chemical methods and the resulting short oligonucleotides were separated and characterized. tthe analytical data permit the conclusion that the tdna transmethylase reacts specifically with N-G-A-T-C-N sequences in which it converts adenine to a 6-methyl-aminopurine residue.

Coliphages↗
PubMed1995

Investigation of the 'n-1' impurity in phosphorothioate oligodeoxynucleotides synthesized by the solid-phase beta-cyanoethyl phosphoramidite method using stepwise sulfurization.

Electrospray ionization mass spectrometry (ESI-MS) of reversed-phase HPLC-purified phosphorothioate oligodeoxynucleotides (S-ODNs), and the single-('n - 1') and double-nucleotide deletion ('n - 2') impurities subsequently isolated from them by preparative polyacrylamide gel electrophoresis (PAGE), has provided direct analytical data for the identification of both S-ODN products and their major oligomeric impurities. The 'n - 1' impurity seen by PAGE consists of a mixture of all possible single deletion sequences relative to the parent S-ODN (n-mer) and results from repetitive, though minor, imperfections in the synthesis cycle, such as incomplete detritylation, or incomplete coupling followed by incomplete capping or incomplete sulfurization. Therefore each possible 'n - 1', 'n - 2', and other short-mer sequence is present only in very low abundance. The conversion of the gel-isolated 'n - 1' impurity from phosphorothioate to phosphodiester followed by base composition-dependent anion-exchange chromatography allowed for independent confirmation of its heterogeneity and quantitation of its various components. ESI-MS of both S-ODN products and their gel-isolated impurities allowed for this first molecular identification of 'n - 1', 'n - 2' and other oligomeric impurities in S-ODNs obtained from state-of-the-art solid-phase synthesis and reversed-phase HPLC purification methods.

Base Sequence↗
PubMed1991

Effect of ethanol administration on the in vivo kinetics of thiamine phosphorylation and dephosphorylation in different organs. I. Chronic effects.

The effects of chronic ethanol administration on different steps in the metabolism of thiamine (T), thiamine mono- (TMP) and pyrophosphate (TPP) were determined in vivo in the liver, kidney, heart, skeletal muscle and small intestinal mucosa. The radioactivity of T and its phosphoesters was measured in plasma and in the selected organs under steady-state conditions and at fixed time intervals (0.25-240 hr) after an i.p. injection of Thiazole-[2-14C]-thiamine (30 micrograms: 1.25 microCi) in rats chronically (35 days) ethanol-treated (daily dose of 4.7 g kg-1 body wt by gastric gavage). Two types of controls were used: pair-fed rats treated with a sucrose solution isoenergetic with ethanol, and water-treated rats. A nutritionally adequate diet, which supplied an excess of thiamine, was given to the rats, producing a virtually steady content of thiamine compounds in the tissues. The analytical data obtained were elaborated using appropriate compartmental mathematical models, which allowed the fractional rate constants, turnover rates and turnover times to be calculated. Alterations in thiamine metabolism were modest and differed according to the organs. The most widespread modification was to facilitate the entry of T (small intestine, kidney and heart) or TMP (small intestine and kidney), while no significant change of T and TMP release was seen. Sucrose had minimal effect in both steps. Enzymatic transformations of thiamine were likewise marginally affected. A general trend toward a slower T pyrophosphorylation and a faster T phosphate dephosphorylation was observed in the small intestine, kidney, heart and liver. Skeletal muscle was unaffected.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcoholism↗
PubMed1975

Sialoglycopeptides isolated from bovine aorta.

Intima-media of bovine aorta was digested with pronase, after preliminary extraction of saline (1%)-soluble substances and fat. Crude glycopeptide fraction was then obtained from the resulting complex carbohydrate fraction by fractionation with CPC (cetylpyridinium chloride). Complete separation of sialoglycopeptides was achieved by chromatography on a DEAE-cellulose column at pH 7.2 followed by repeated chromatography on a DEAE-Sephadex A-25 column at pH 5.2. Nine sialoglycopeptides (SGP 1-SGP 9) thus obtained were homogeneous on high-voltage paper electrophoresis at pH 3.5 and pH 5.2. The analytical data showed great heterogeneity of the carbohydrate chains of these preparations, although they consisted of the same monosaccharides (galactose, glucose, mannose, glucosamine, galactosamine, fucose, and sialic acid), except that SGP 1 lacked galactosamine. Heterogeneity was also observed in their peptide chains. It was noticed, however, that the contents of hexose, hexosamine, and aspartic acid of the fractions (SGP 3, SGP 4, and SGP 5) which eluted from the DEAE-Sephadex A-25 column at lower molarity of the eluting salt were higher than those of the fractions (SGP 7, SGP 8, and SGP 9) which eluted at higher molarity, while the contents of sialic acid and hydroxyamino acids were in an opposite relationship. Representative fractions (SGP 7 and SGP 9) of the latter contained many more alkali-sensitive linkages than those (SGP 3 and SGP 5) of the former, indicating the presence of many more O-glycosidic linkages between hydroxyamino acid(s) and sugar(s) in the latter than in the former. The sialoglycopeptides contained significant amounts of sialic acid, ranging from 10% (sgp 1) to 32.4% (SGP 8). The highest contents were in SGP 8 and SGP 9, which contained equimolar amounts of sialic acid and hexosamine. Furthermore, infrared spectra indicated the presence of sulfate groups in most of the sialoglycopeptides.

Amino Acids↗
PubMed1975

Isolation and characterization of a sulfated glycoprotein from rabbit uterus.

Crude glycoproteins were extracted with 0.15 M NaCl from the pooled endometrial scrapings of rabbit uteri after treatment with estrogen. The crude glycoproteins were fractionated with ammonium sulfate, followed by DEAE-cellulose column chromatography, treatment with CM-Sephadex C-25 and gel filtration on Sephadex G-200. Subsequently, purification of an acidic glycoprotein was carried out by gel filtration on Sephadex G-200 and then Sepharose 4B. The results of electrophoresis and enzymatic digestion, together with analytical data and the infrared spectrum indicated that the acidic glycoprotein was a sulfated glycoprotein.

Amino Acids↗
PubMed1976

Proteochondroitin sulfate A in the euglobulin fraction of human plasma.

Euglobulin fraction of human plasma was extracted with 0.01 M phosphate buffer (pH 7.3) (PB) containing 1 M NaCl. The substances in the extract were separated by DEAE-cellulose column chromatography into two uronic acid-containing fractions (0.5 Fr and 0.75 Fr). The major fraction (0.75 Fr) was eluted at the void volume in gel filtration on Sephadex G-200, yielding 0.75-G Fr. 0.5 Fr and 0.75 Fr and their pronase digestion products (0.5-P Fr and 0.75-P Fr) together with 0.75-G Fr were examined by electrophoresis on cellulose acetate membrane. The results of electrophoresis and the digestibility with mucopolysaccharidases of these fractions indicated that 0.5 Fr and 0.75 Fr contained proteochondroitin sulfate A. It is suggested that chondroitin sulfate A in 0.5 Fr might be less sulfated than that in 0.75 Fr. Furthermore, analytical data and the infrared spectrum of 0.75-G Fr supported the above view.

Chondroitin Sulfate Proteoglycans↗
PubMed1979

Isolation and identification of the reaction product of alpha-hydroxy-gamma-carboxymuconic epsilon-semialdehyde dehydrogenase.

The reaction product of enzymic dehydrogenation of alpha-hydroxy-gamma-carboxymuconic epsilon-semialdehyde (HCMS) was isolated. The analytical data (elemental analyses, IR spectra, mass spectra, proton NMR spectra, and UV spectra) showed that the product was not alpha-hydroxy-gamma-carboxymuconic acid (HCMA), the expected primary product of HCMS dehydrogenation, but a lactone of HCMA. The structure of the lactone was tentatively determined as alpha-pyrone-4,6-dicarboxylic acid. HCMS was converted stoichiometrically to the lactone by the purified NAD(P)-linked HCMS dehydrogenase. The lactone was actively metabolized by a cell-free extract prepared from Pseudomonas ochraceae grown on phthalic acid, suggesting that it may be a metabolic intermediate in the bacterial metabolism of protocatechuic acid. Furthermore, a method for the chemical synthesis of the lactose of HCMA is presented and some of its chemical and biochemical properties are described.

Aldehyde Oxidoreductases↗
PubMed1981

Preparation of biologically active fluorescent heparin composed of fluorescein-labeled species and its behavior to antithrombin III.

A hog-mucosal heparin purified gel-chromatographically (total sulfate, 2.20; N-sulfate, 0.82; N-acetyl, 0.15 (mol/mol HexN); activity, 184 USP units/mg) was partially N-desulfated to give a product (total sulfate, 2.12; N-sulfate, 0.71 (mol/mol HexN); activity, 159 USP units/mg). The free amino groups in the product was extensively labeled with fluoresceinylthiocarbamoyl (FTC) groups, and the labeled product was chromatographed on Octyl-Sepharose CL-4B to give a heparin preparation of fluorescein-labeled species (total sulfate, 2.04; N-sulfate, 0.72; degree of substitution, 0.059 (mol/mol HexN); activity, 155 USP units/mg). The fluorescent heparin thus obtained was indicated from its analytical data to have one FTC group pr heparin molecule irrespective of the molecular weight. The fluorescent heparin was separated into the low-affinity (56.6%) and high-affinity (43.4%) fractions for antithrombin III, and the anticoagulant activities of the two types of fluorescent heparin were compared with those of the starting heparin and the partially N-desulfated heparin, suggesting that FTC-substitution in heparin molecules had no effect on the known biological interaction with mobilized or immobilized antithrombin III.

Animals↗
PubMed1981

Comparative studies on the structures of highly active and relatively inactive forms of whale heparin.

Whale heparin was separated by affinity chromatography on an antithrombin III-Sepharose column into two distinct fractions. The high-affinity fraction accounted for most the anticoagulant activity of the unfractionated material, while the low-affinity fraction was relatively inactive. The yields of the two fractions were substantially equivalent. No significant difference was observed between these fractions in terms of electrophoretic mobilities on cellulose acetate membrane and analytical data except for the contents of N-acetylglucosamine and N-sulfoglucosamine. The highly active form contained more N-acetylglucosamine and less N-sulfoglucosamine than the relatively inactive form. The two fractions were separately subjected to the sequential digestion with purified heparinase and heparitinase, and the oligosaccharide fractions were isolated from the digests by DEAE-cellulose column chromatography, followed by preparative paper chromatography. The purified compounds were then characterized by routine chemical and physical methods. Compound 1, delta 4,5hexosyuronic acid1 leads to 4N-acetylglucosamine, was exclusively obtained from the highly active form, whereas compound 3a, delta 4,5hexosyluronic acid1 leads to 4N-acetylglucosamine 6-sulfate, and compound 3b delta 4,5hexosyluronic acid1 leads to 4-sulfoglucosamine, were the only ones obtained from the relatively inactive form. The yields of other oligosaccharide fractions from both forms were comparable. The present data suggest that an N-acetylglucosamine-containing oligosaccharide structure in whale heparin is essential for binding to antithrombin II.

Animals↗
PubMed1982

Structures and biological activities of peptidoglycans of Listeria monocytogenes and Propionibacterium acnes.

The cell-wall skeletons of Listeria monocytogenes strain EGD and Propionibacterium acnes strain C7, which have the ability to induce macrophage activation, were analyzed, and the structures of the peptidoglycans were investigated. The analytical data indicate that both peptidoglycans have glucosamine residues with free amino groups, which are responsible for the resistance to lysozyme. Possible structures of these peptidoglycans were deduced from the composition and the results of determination of N- and C-terminal amino acids, together with the characterization of fragments obtained by enzymatic treatment and partial acid hydrolysis of both peptidoglycans. The results suggested that the peptidoglycan of L. monocytogenes contains a cross-linkage region of peptide chains with meso-diaminopimelic acid and D-alanine, which belongs to the A1 gamma type (Schleifer, K.H. & Kandler, O. (1972) Bacteriol. Rev. 36, 407-477), whereas the peptidoglycan of P. acnes contains a cross-linkage region of peptide chains with L,L-diaminopimelic acid and D-alanine, in which two glycine residues combine with amino and carboxyl groups of two L,L-diaminopimelic acid residues. The latter type should be classified as a new type. These cell-wall skeletons and peptidoglycans were shown to have immunoadjuvant activity on the induction of delayed-type hypersensitivity and suppressive activity on the growth of 3-methylcholanthrene-induced fibrosarcoma in BALB/c mice, and the peptidoglycans were shown to be an immunological-active principle of these cell-wall skeletons.

Amino Acids↗
PubMed1984

Thrombin-inhibitory activity of whale heparin oligosaccharides.

Whale heparin was partially digested with a purified heparinase and the oligosaccharide fractions with 8-20 monosaccharide units were isolated from the digest by gel filtration on Sephadex G-50, followed by affinity chromatography on a column of antithrombin III immobilized on Sepharose 4B. A marked difference in the inhibitory activity for thrombin in the presence of antithrombin III was observed between the high-affinity fractions for antithrombin III of octasaccharide approximately hexadecasaccharide and those of octadecasaccharide approximately eicosasaccharide. The disaccharide compositions of these hexadeca-, octadeca-, and eicosasaccharides were analyzed by high-performance liquid chromatography after digestion with a mixture of purified heparitinases 1 and 2 and heparinase. The analytical data indicated that the proportions of trisulfated disaccharide (IdUA(2S)alpha 1----4GlcNS(6S)) and disulfated disaccharide (UA1----4GlcNS(6S)) increased with the manifestation of high thrombin-inhibitory activity, while that of monosulfated disaccharide (UA1----4GlcNS) decreased. The present observations, together with those so far reported, suggest that the presence of the former structural elements, specifically IdUA(2S)alpha 1----4GlcNS(6S), as well as the antithrombin III-binding pentasaccharide at the proper positions in the molecules of whale heparin oligosaccharides is essential for the manifestation of high inhibitory activity for thrombin in the presence of antithrombin III. The structural bases for the manifestation of the anticoagulant activity of whale and porcine heparins and their oligosaccharides are also discussed.

Animals↗
PubMed2001

Soluble HLA class I antigens in serum and synovial fluid from patients with rheumatoid arthritis and other arthropathies.

OBJECTIVES: To investigate the presence of soluble HLA class I (s-HLA) antigens in serum and synovial fluid (SF) from a large cohort of rheumatic patients. METHODS: We studied clinical and analytical data and serum samples from 300 patients [122 patients with rheumatoid arthritis (RA), 38 with osteoarthritis or osteoporosis, 29 with seronegative spondyloarthropathies, 45 patients with other rheumatic diseases] and 66 healthy controls. In addition, we studied 25 paired samples of serum and SF from these groups of subjects. In RA patients, we examined whether the levels of s-HLA in serum and SF were related to the activity of the disease. RESULTS: The mean concentrations of s-HLA molecules in serum were slightly higher in RA patients (1.2 microg/ml) than in the other four groups (1.08, 1.01, 1.09 and 0.94 microg/ml respectively). We found no correlation between serum s-HLA levels and any variable of inflammatory disease activity in RA patients. s-HLA molecules were found in SF and at levels that correlated with those found in serum (P=0.04; r=0.4). Furthermore, s-HLA levels were higher in SF from patients with RA (1.3 microg/ml) or crystal-induced arthritis (0.98 microg/ml) than in SF from those with osteoarthritis (0.38 microg/ml) (P<0.05 and P<0.005 respectively), and these levels were correlated inversely and significantly with the score on the visual analogue scale of pain (P=0.02), the number of painful joints (P=0.05) and the level of C-reactive protein (P=0.03) in RA patients. CONCLUSIONS: This is the first report to demonstrate the presence of s-HLA molecules in SF at levels that correlate with serum levels. The mean levels of s-HLA molecules were significantly higher in SF from patients with RA and crystal-induced arthritis than in SF from cases of osteoarthritis, and correlated inversely with certain variables of disease activity in RA patients.

Adult↗