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  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of agricultural and food chemistry 35 (1987), S. 178-182 
    ISSN: 1520-5118
    Source: ACS Legacy Archives
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Analytical chemistry 41 (1969), S. 650-652 
    ISSN: 1520-6882
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0738
    Keywords: Polychlorinated dibenzofurans (PCDFs) ; 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) ; Aryl hydrocarbon hydroxylase (AHH) activity ; AHH responsiveness ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Hepatic aryl hydrocarbon hydroxylase (AHH)-inducing potency of toxic polychlorinated aromatic hydrocarbons such as polychlorinated dibenzofurans (PCDFs), 3,4,5,3′,4′,5′-hexachlorobiphenyl (HCB) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was studied in four inbred strains of mice with different phenotypes of Ah locus, i.e., AHH-responsive strains: C57BL/6N and AKR/Ms Qdj, and AHH-nonresponsive strains: DBA/2Cr Slc and Qdj; DDD. Eight individual PCDF isomers or TCDD were administered IP in doses of 30 μg/kg; HCB was given in a dose of 120 μg/kg. In AHH-nonresponsive strains of mice, only TCDD significantly induced hepatic AHH activity, while in AHH-responsive strains, 2,3,7,8-tetrachlorodibenzofuran(2,3,7,8-TCDF), 1,2,3,7,8-pentachlorodibenzofuran(1,2,3,7,8-PCDF) 2, 3, 4, 7, 8-pentachlorodibenzofuran (2, 3,4, 7, 8-PCDF), and TCDD significantly enhanced the enzyme activity, and the induced AHH activities with the three PCDF isomers were about 30–65% of those of TCDD. These results indicate that AHH responsiveness in mice segregates with the induction of AHH activity by PCDF isomers and may also segregate with the toxic potency of the isomers; i.e., toxic potencies of 2,3,7,8-TCDF, 1,2,3,7,8-PCDF, and 2,3,4,7,8-PCDF in AHH-responsive strains of mice may be much greater than those in AHH-nonresponsive strains of mice. Taking into account both the potent AHH inducibility and the high bioaccumulation of 2,3,7,8-TCDF, 1,2,3,7,8-PCDF, and 2,3,4,7,8-PCDF, these three PCDF isomers should be given greater attention with regard to environmental contamination.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-0738
    Keywords: Key words Polychlorinated biphenyl ; Methylsulfonyl metabolite ; Total thyroxine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Male Sprague-Dawley rats received four consecutive intraperitoneal doses of four kinds of methylsulfonyl (MeSO2) metabolites of polychlorinated biphenyl (PCB) congeners: 3-MeSO2-2,2′,3′,4′,5,6-hexachlorobiphenyl (3-MeSO2-CB132); 3-MeSO2-2,2′,3′,4′, 5,5′-hexachlorobiphenyl (3-MeSO2-CB141); 3-MeSO2-2,2′,4′,5,5′,6-hexachlorobiphenyl (3-MeSO2-CB149) and 4-MeSO2-2,2′,4′,5,5′,6-hexachlorobiphenyl (4-MeSO2-CB149). The congeners were major MeSO2-PCBs determined in human milk, liver and adipose tissue, and the aim was to determine their effect on thyroid hormone levels. All four tested MeSO2 metabolites (20 μmol/kg once daily for 4 days) reduced serum total thyroxine levels by 22–44% at a much lower dose than phenobarbital (PB; 431 μmol/kg once daily for 4 days) on days 2, 3, 4 and 7 after the final doses. Total triiodothyronine levels were reduced 37% by treatment with 4-MeSO2-CB149 at day 7. A 30% increase in thyroid weight was produced by 3-MeSO2-CB141 treatment. Total cytochrome P450 content was increased by 3-MeSO2-CB132, 3-MeSO2-CB141 and 3-MeSO2-CB149, but not by 4-MeSO2-CB149. Thus, it is likely that the 3-MeSO2-hexachlorobiphenyls and 4-MeSO2-CB149 could influence the thyroid hormone metabolism by different mechanism(s). The results show that tested 3- and 4-MeSO2 metabolites of PCB congeners reduce thyroid hormone levels much more than PB in rats. Our finding suggests that the metabolites may act as endocrine-disrupters.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-0738
    Keywords: Polychlorinated dibenzofurans (PCDFs) ; 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) ; Aryl hydrocarbon hydroxylase (AHH) inducibility ; Toxicity ; Human lymphoblastoid cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aryl hydrocarbon hydroxylase(AHH)-inducing potency of toxic polychlorinated aromatic hydrocarbons such as polychlorinated dibenzofuran (PCDF) isomers, 3,4,5,3′,4′,5′-hexachlorobiphenyl (HCB) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was investigated in human lymphoblastoid cell lines with different AHH inducibility for 3-methylcholanthrene (3-MC) obtained from healthy subjects. Each of the cell lines was treated with eitht individual PCDF isomers, TCDD, and HCB at doses of 1.9–15 ng/ml of culture medium, 1.9–7.5 ng/ml and 95 ng/ml, respectively. Lymphoblastoid cell lines were arbitrarily classified into three groups based on their AHH inducibilities with 3-MC (2.5 μM); low (3-MC/ control=I〈3), middle (3〈=I〈6) and high (I〉=6). Degrees of the enzyme inducibilities of the organochlorine compounds proportionally increased with those for 3-MC. AHH inducibilities with 2,3,4,7,8-pentachlorodibenzofuran(2,3,4,7,8-PCDF), 1,2,3,4,6,7-hexachlorodibenzofuran(1,2,3.4,6,7-HCDF) and 1,2,3,4,7,8-hexachlorodibenzofuran(1,2,3,4,7,8-HCDF) were comparable to those of TCDD at doses of 7.5 ng/ ml, and about twice as high as those of 2,3,7,8-tetrachlorodibenzofuran (TCDF), at the same dose, HCB, at a dose of 95 ng/ ml, did not induce enzyme activity. The experimental evidence indicated that AHH inducibility by the organochlorine compounds reflected the genetic susceptibility of the cells to the phenomenon of induction, and PCDF isomers found at relatively high concentrations in tissues of mammals exerted the highest values of AHH induction.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Bulletin of environmental contamination and toxicology 48 (1992), S. 877-883 
    ISSN: 1432-0800
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 221 (1969), S. 254-256 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The mainstream smoke of 300 US non-filter cigarettes4 was led through cold methanol containing 3.5 per cent HC1. The dry, basic fraction of the trapped smoke (3.0 g) was dissolved in ether and treated with penta-fluoropropionic anhydride (1.5 g). After 18 h at room temperature the ether solution ...
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1432-0738
    Keywords: Polychlorinated dibenzofurans (PCDFs) ; Aryl hydrocarbon hydroxylase (AHH) ; Enzyme induction ; Structure activity relationship ; Toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The aryl hydrocarbon hydroxylase (AHH) inducing potency of toxic chlorinated aromatic hydrocarbons such as polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was studied in the young male Wistar rats. Alternatively, a technical PCDF mixture, 15 individual PCDF isomers or TCDD were administered i.p. in doses of 5 μg/kg; a PCB mixture was given in a dose of 50 mg/kg. The order of AHH inducing ability was TCDD 〉 PCDFs ≫ PCBs in kidney, lung, and liver. In the prostate, thymus, and spleen, only TCDD enhanced the AHH activity. The AHH inducibility in the lung and liver, induced by 15 pure PCDF isomers with varying chlorine substitutions was also examined. Only 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-tetra-CDF) and 2,3,4,7,8-pentachlorodibenzofurans (2,3,4,7,8-penta-CDF) significantly induced the hepatic AHH activity (4- and 2-fold, respectively), while eight PCDF isomers, including these two, significantly enhanced the pulmonary AHH activity (6- to 30-fold). Taking into account both the potent AHH inducibility and the high bioaccumulation of these compounds, 2,3,7,8-tetra- and 2,3,4,7,8-penta-CDF should be given due attention with regard to environmental-related factors and the possibility of involvement in the etiology of “Yusho” disease.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1432-0738
    Keywords: Key words Polychlorinated biphenyl ; Methylsulfonyl metabolite ; Gap junction intercellular communication ; IAR 20 rat liver epithelial cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effects of three polychlorinated biphenyl (PCB) congeners and their six methylsulfonyl (MeSO2)-metabolites on cell communication have been investigated in the scrape-loading/dye-transfer assay in IAR 20 rat liver epithelial cells. The results demonstrated that at non-cytotoxic concentrations 2,2′,4′,5-tetrachlorobiphenyl, 2,2′,4′,5,5′-pentachlorobiphenyl (2,2′,4′,5,5′-pentaCB), 2,2′,4′,5,5′,6-hexachlorobiphenyl (2,2′,4′,5,5′, 6-hexaCB), and their 3- and 4-MeSO2 derivatives completely inhibited the cell communication within 1 h. 4-MeSO2-2,2′,4′,5,5′-pentaCB and 4-MeSO2-2,2′,4′,5, 5′,6-hexaCB appeared to inhibit the cell communication at slightly lower concentration than their parental PCB congeners and 3-MeSO2 derivatives. The results show that 3- and 4-MeSO2 derivatives of the PCB congeners tested inhibit gap junction intercellular communication at about the same potency as their parental compounds. Since inhibition of cell communication is often observed after treatment with many tumor promoters, our findings suggest that the metabolites may also act as tumor promoters.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 237 (1972), S. 41-42 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Because of their unique physical and chemical characteristics, PCBs are widely used in industry as heat transferring media, electric insulators, lubricants, plasticizers and so forth. PCBs are also used for manufacturing carbonless copying paper, the use of which has rapidly increased in Japan in ...
    Type of Medium: Electronic Resource
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