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  • Urine  (5)
  • Chemistry  (4)
  • Biological monitoring  (2)
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Amino acids 1 (1991), S. 239-246 
    ISSN: 1438-2199
    Schlagwort(e): Amino acids ; d-Amino-acid oxidase ; d-Aminoaciduria ; Physiological role ; Mutant mice ; d-Amino acids ; Urine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Urine of mutant ddY/DAO− mice lackingd-amino-acid oxidase activity contained more serine and proline than that of normal ddY/DAO+ mice.d-Amino-acid oxidase treatment of urinary amino acids decreased the serine and proline, suggesting that they containedd-isomers. An HPLC analysis confirmed the presence ofd-serine. Urinary serine and proline contents were not decreased when the ddY/DAO− mice were fed a diet which did not contain supplementaryd-methionine or when they were given water containing antibiotics. These results suggest that thed-serine andd-proline do not derive from thed-methionine supplemented in the diet or from intestinal bacteria. In urine of the ddY/DAO− mice, a substance which seemed to bed-methionine sulfoxide and/ord-methionine sulfone was present. It is probably a metabolite of thed-methionine supplemented in the diet. Thed-aminoaciduria in the mutant mice lackingd-amino-acid oxidase activity indicates that this enzyme is involved in the metabolism of thed-amino acids in normal mice.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    International archives of occupational and environmental health 73 (2000), S. 26-34 
    ISSN: 1432-1246
    Schlagwort(e): Key words Biological exposure monitoring ; Blood ; Cadmium environmental exposure ; Food ; Japanese women ; Urine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objectives: The Japanese people are known to have high environmental exposure to cadmium (Cd). The present survey was initiated to elucidate possible changes in the intensity of Cd exposure to the population by comparison of the present exposure level with the situation some 15 years ago. Methods: During 1991–1997, 24-h food-duplicate samples, peripheral blood specimens and morning spot urine samples were collected from 588 non smoking women from 27 survey sites in six regions, where food-duplicate and blood samples had also been obtained during 1977–1981 from 399 women. The samples were wet-ashed (after homogenization in the case of food-duplicates), and Cd in the wet-ashed samples was analyzed by inductively-coupled plasma mass spectrometry for Cd intake via foods (Cd-F), Cd concentration in blood (Cd-B) and Cd concentration in urine (Cd-U). The Cd-F and Cd-B were compared with the Cd-F and Cd-B obtained at the same sites in the 1977–1981 survey. Results: The exposure levels during 1991–1997 were such that Cd-F, Cd-B and Cd-Ucr (Cd–U after correction for creatinine concentration) were 25.5 μg/day, 1.90 μg/l and 4.39 μg/g creatinine. Comparison with the 1977–1981 survey results (i.e., 37.5 μg/day for Cd-F and 3.47 μg/l for Cd-B) showed that there were significant reductions (by 32 and 45%) in both parameters respectively during the last 15 years. The dietary route was an almost exclusive (i.e., 99% of the sum of dietary and respiratory uptake) route of Cd uptake, of which Cd in rice (11.7 μg/day) contributed about 40% of the total dietary intake. When compared among survey sites, inter-site variation in dietary Cd intake was primarily due to differences in the intake through boiled rice. Despite the recent reduction in Cd exposure, the current exposure level for Japanese people is still higher than the levels among other rice-dependent populations in Asia as well as in other parts of the world. Comparison was made between the present findings in general populations and observations among known Cd-pollution cases in Japan. Conclusions: Dietary uptake is an almost exclusive route of Cd exposure in the general Japanese population. Boiled rice is a strong determinant of variation in dietary Cd intake. Whereas there was a substantial reduction in Cd exposure among Japanese populations in the last 15 years, the current level is still high when compared internationally.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    International archives of occupational and environmental health 73 (2000), S. 449-456 
    ISSN: 1432-1246
    Schlagwort(e): Key words Acetone ; Biological monitoring ; Hexane ; 2 ; 5-Hexanedione ; Toluene ; Ethyl acetate ; Urinalysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective: To investigate whether metabolic interactions exist between hexane (HEX) and other solvents when co-exposed at the levels below occupational exposure limits. Methods: Workers, 219 men in ten workshops in total, volunteered to participate in the study. They were occupationally exposed to mixtures of HEX and one or more of toluene (TOL), ethyl acetate (EA) and acetone (ACE). Time-weighted average intensity of vapor exposures was monitored by diffusive personal sampling. `Free'- and `total'-2,5-hexanedione (HD) levels in the end-of-shift urine samples were determined by gas chromatography (GC) before and after acid hydrolysis of urine, respectively, and expressed as observed (HDob) or after correction for creatinine concentration (HDcr) or urine specific gravity (HDsg). Possible interaction was examined by multiple regression analysis (MRA), taking either free- or total-HD as a dependent variable, and the four solvent concentrations as independent variables. Results: In most cases, exposure intensity did not exceed the current occupational exposure limits even when additiveness was assumed. In addition that HEX was the most influential independent variable in all cases as expected, the MRA showed that, in cases of free-HD, ACE was also influential to HDob although weakly, but not to HDcr or HDsg. With regard to total-HD, ACE was weakly influential to HDob and HDsg, and EA also weakly to HDcr. The effect of ACE on free- or total-HD was not detected, however, when 22 men exposed only to HEX and ACE were subjected to the same analysis. Similarly, the effect of EA on total-HD was not observed among the remaining 197 men exposed to HEX, TOL and EA only. Conclusions: When the exposures were below occupational exposure limits, the free-HD levels in urine after HEX exposure will not be modified by co-exposures to TOL, EA or ACE.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    International archives of occupational and environmental health 41 (1978), S. 125-138 
    ISSN: 1432-1246
    Schlagwort(e): Amylphenol ; Biological monitoring ; Butylcatechol ; Butylphenol ; Isopropylcatechol ; Methylcatechol ; Nonylphenol ; Octylphenol ; Phenylphenol ; Urinalysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary GLC systems are developed for quantitative urinalysis of leucodermogenic phenols and catechols, i. e., p-tert.-butylphenol, p-tert. Amyphenol, p-octylphenol, p- and o-phenylphenol, 3- and 4-methylcatechol, 3-isopropylcatechol, and 4-tert.-butylcatechol. The systems were successfully applied for the exposure assessment of the workers in factories producing p-tert.-butylphenol, p-octylphenol and/or 4-tert.-butylcatechol. In accordance with estimated exposure intensities, the concentrations in the urine of product packers were higher than those of plant operators and engineers. The levels were reduced by the improvement of hygienic conditions in the workshops. Importance of biological monitoring is discussed in relation with the possible skin penetration. From the data obtained, BP concentration in urine, 2 μg/ml, is tentatively proposed as a urinary biological threshold limit value to prevent leucodermogenic effect.
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    International archives of occupational and environmental health 73 (2000), S. 15-25 
    ISSN: 1432-1246
    Schlagwort(e): Key words Biological exposure monitoring ; Blood ; Cadmium ; Environmental exposure ; Food ; Urine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objectives: To examine whether the current level of environmental exposure to cadmium (Cd) is associated with kidney dysfunction among general populations in Japan. Methods: A nationwide survey was conducted in Japan from 1991 to 1997 at 30 survey sites (with no known environmental heavy metal pollution), by the collection of 24-h food-duplicate samples, peripheral blood specimens and morning spot urine samples. In practice, 607 non-smoking adult women provided these samples. After being wet-ashed, the samples were analyzed for Cd in food duplicates (Cd-F), in blood (Cd-B) and urine (Cd-U) by inductively-coupled plasma mass spectrometry (ICP-MS). Urine samples were also analyzed for α1-microglobulin (α1-MG), β2-microglobulin (β2-MG) and retinol-binding protein (RBP), creatinine (cr) and specific gravity. Possible tubular dysfunction in association with Cd exposure was examined by simple, multiple and logistic regression analyses, and comparison among three different Cd-dose groups. To minimize the confounding effects of aging, 367 women from 41 to 60 years old were selected and subjected to the same statistical analyses. Results: The analysis of a whole population of 607 women showed that α1-MG and possibly β2-MG increased as a function of Cd-F, Cd-B and Cd-U. When the analysis was repeated with the selected population of 367 women aged 41–60, the Cd dose-dependent changes in α1-MG and β2-MG became less evident. The distribution of the selected population with α1-MG above two low cut-off values of 〉4.9 and 〉8.4 mg/g cr or with β2-MG above the lowest cut-off value of 〉400 μg/g cr, was biased toward the group with higher Cd-Ucr, but such bias was not significant for both α1-MG and β2-MG when higher cut-off values were employed. No bias was detected with RBP. Logistic regression analysis with α1-MG, β2-MG and RBP (with cut-off values given above) in combination with age, Cd-F, Cd-B and Cd-Ucr gave essentially the same results. Conclusions: The evidence for kidney dysfunction was of borderline significance in the present study population for which geometric mean Cd-F, Cd-B and Cd-U were 24.7 μg/day, 1.76 μg/l, and 3.94 μg/g cr, respectively. The findings might suggest at the same time that the safety margin is small for the Japanese general population regarding environmental Cd exposure.
    Materialart: Digitale Medien
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  • 6
    ISSN: 1432-1246
    Schlagwort(e): Key words Biological exposure monitoring ; Blood ; Cadmium ; Environmental exposure ; Food ; Lead ; Urine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective: To examine whether lead (Pb) in urine and cadmium (Cd) in blood, especially the former, can be used as markers of environmental exposure of general populations to these metals. Methods: Between 1991 and 1998, spot urine and peripheral blood samples, together with 24 h duplicates of food intake were collected from 607 non-smoking adult women in 30 survey sites (SS) in seven administrative regions all over Japan. Urine, blood and food duplicate samples were analyzed by inductively-coupled plasma spectrometry, for Cd and Pb in urine (Cd-U and Pb-U), in blood (Cd-B and Pb-B) and in food duplicates (Cd-F and Pb-F). Correlation between the measurements was examined by regression analysis. Results: The Cd-B correlated closely with Cd-U, and both Cd-B and Cd-U with Cd-F, on an individual basis (n = 607), on an SS basis (n = 30) and on a regional basis (n = 7). The Pb-U however did not correlate with Pb-B on a regional basis although they correlated with each other when analyzed on an individual as well as SS basis. Moreover, the correlation coefficients between Pb-U and Pb-B were much smaller than those between Cd-U and Cd-B. Neither Pb-U nor Pb-B showed significant correlation with Pb-F on any levels of statistical analysis. Conclusions: Both Cd-B and Cd-U can be employed as biomarkers of environmental Cd exposure. The reliability of Pb-U for use in place of Pb-B appeared to be small.
    Materialart: Digitale Medien
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  • 7
    ISSN: 1438-2199
    Schlagwort(e): Amino acids ; Hydroxyproline ; Dabsyl-chloride ; Urine ; High-performance liquid chromatography ; o-Phthalaldehyde
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary In order to analyse hydroxyproline (HYP) in urine, a high-performance liquid chromatographic method was modified. The primary amino groups were blocked with o-phthalaldehyde, and then the secondary amino groups were derivatized with 4-dimethylaminoazobenzene-4′-sulphonyl chloride. In addition, the dabsylated samples were treated with ethyl acetate to obtain a simple elution profile in high-performance liquid chromatography. The dabsyl-HYP and -proline were eluted at 4.7 min and 8.0 min, respectively. The chromatographic analysis was completed within 10 min, including the time needed for reequilibration of the column. Using the present method, the concentration of HYP in urine was determined to 260 ± 6µmol/l.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 5 (1971), S. 61-71 
    ISSN: 0030-493X
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The mass spectral fragmentation behaviour of N-acyliminopyridinium and isoquinolinium betaines has been investigated. Major fragmentations of the pyridinium betaines can be rationalized in terms of charge localization on the pyridinium nitrogen. The most prominent process is α-cleavage followed by loss of NCO to furnish a pyridine ion. The electron-impact induced fragmentation of N-benzoyliminopyridinium betaine (I) was compared with that of thermolysis. The completely analogous behaviour has been observed in the corresponding isoquinolinium betaines.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 9
    Digitale Medien
    Digitale Medien
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 5 (1971), S. 935-938 
    ISSN: 0030-493X
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The mass spectra of N-iminopyridinium betaines, which have been generated within the ion source by pyrolysis of the corresponding hydrochlorides, have been compared with those of pyridine N-oxides.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 5 (1971), S. 389-396 
    ISSN: 0030-493X
    Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The mass spectra of various N-aryliminopyridinium and isoquinolinium betaines have been recorded. The most prominent fragmentation process of these compounds is N-N bond cleavage with the charge retention on both the pyridine and aryl fragments. An ortho-effect has been observed in the mass spectrum of N-o-nitrophenyliminopyridinium betaine (IXa).
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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