Polychlorinated dibenzofurans (PCDFs): Correlation between in vivo and in vitro structure-activity relationships

GA Strategy for Variable Selection in QSAR Studies: GA-Based Region Selection for CoMFA Modeling

“…Also, as shown in Figure C, the contributions of positions C-3 and C-7 to the binding affinity are larger than those of positions C-2 and C-8. This structural requirement is also consistent with the results in the previous studies. , …”

“…In Figure , it was shown that the important regions are located around the lateral positions of the PCDF molecules. In the previous structure−activity relationship study, it was proposed that the chlorine atoms at a lateral position are an advantage for the binding affinity of the PCDF molecules. − These structural requirements are consistent with the result of this CoMFA modeling. The coefficient contour map in Figure clearly indicates the corresponding regions, and the utility of CoMFA with GARGS is validated.…”

GA Strategy for Variable Selection in QSAR Studies: GA-Based Region Selection for CoMFA Modeling

“…Also, as shown in Figure C, the contributions of positions C-3 and C-7 to the binding affinity are larger than those of positions C-2 and C-8. This structural requirement is also consistent with the results in the previous studies. , …”

“…In Figure , it was shown that the important regions are located around the lateral positions of the PCDF molecules. In the previous structure−activity relationship study, it was proposed that the chlorine atoms at a lateral position are an advantage for the binding affinity of the PCDF molecules. − These structural requirements are consistent with the result of this CoMFA modeling. The coefficient contour map in Figure clearly indicates the corresponding regions, and the utility of CoMFA with GARGS is validated.…”

Synthesis of Polybrominated Diphenyl Ethers and Their Capacity to Induce CYP1A by the Ah Receptor Mediated Pathway

“…In conclusion, PBDEs contribute to the total "dioxin-like" activity of environmental samples, although their activity is much less than that of potent HACs such as PCDDs, PCDFs, and coplanar PCBs. Only a subset of the PBDEs induces EROD activity, as is true also for PCDDs (56), PCDFs (57), PCBs (43,58,59), PBBs (60), polychlorinated naphthalenes (PCNs) (61), and polycyclic aromatic hydrocarbons (PAHs) (62,63). The most active PBDE congeners are more potent than mono ortho PCBs (43,58,59), with REPs similar to those observed for PCNs (60) and PAHs (61,62).…”

Comparative toxicity of four chlorinated dibenzo-p-dioxins (CDDs) and their mixture

“…Several other studies have, however, been conducted using mixtures of CDDs and/or chlorinated dibenzofurans (CDFs) to examine different biological or toxicological endpoints. Most of these studies also suggest an additive action of the individual compounds Weber et al 1985;Mason et al 1985;Pluess et al 1988). However, competitive effects of CDDs and CDFs on enzyme induction and immune toxicity have been reported in one study (Rizzardini et al 1983) as well as in a 51/2 week feeding study with a mixture of CDDs and CDFs obtained by extraction of particulate matter from a municipial waste incinerator (Suter-Hofmann and Schlatter 1986), without providing an explanation for this finding.…”

GA Strategy for Variable Selection in QSAR Studies: GA-Based Region Selection for CoMFA Modeling

“…Also, as shown in Figure C, the contributions of positions C-3 and C-7 to the binding affinity are larger than those of positions C-2 and C-8. This structural requirement is also consistent with the results in the previous studies. , …”

“…In Figure , it was shown that the important regions are located around the lateral positions of the PCDF molecules. In the previous structure−activity relationship study, it was proposed that the chlorine atoms at a lateral position are an advantage for the binding affinity of the PCDF molecules. − These structural requirements are consistent with the result of this CoMFA modeling. The coefficient contour map in Figure clearly indicates the corresponding regions, and the utility of CoMFA with GARGS is validated.…”

Synthesis of Polybrominated Diphenyl Ethers and Their Capacity to Induce CYP1A by the Ah Receptor Mediated Pathway

“…In conclusion, PBDEs contribute to the total "dioxin-like" activity of environmental samples, although their activity is much less than that of potent HACs such as PCDDs, PCDFs, and coplanar PCBs. Only a subset of the PBDEs induces EROD activity, as is true also for PCDDs (56), PCDFs (57), PCBs (43,58,59), PBBs (60), polychlorinated naphthalenes (PCNs) (61), and polycyclic aromatic hydrocarbons (PAHs) (62,63). The most active PBDE congeners are more potent than mono ortho PCBs (43,58,59), with REPs similar to those observed for PCNs (60) and PAHs (61,62).…”

Comparative toxicity of four chlorinated dibenzo-p-dioxins (CDDs) and their mixture

“…Several other studies have, however, been conducted using mixtures of CDDs and/or chlorinated dibenzofurans (CDFs) to examine different biological or toxicological endpoints. Most of these studies also suggest an additive action of the individual compounds Weber et al 1985;Mason et al 1985;Pluess et al 1988). However, competitive effects of CDDs and CDFs on enzyme induction and immune toxicity have been reported in one study (Rizzardini et al 1983) as well as in a 51/2 week feeding study with a mixture of CDDs and CDFs obtained by extraction of particulate matter from a municipial waste incinerator (Suter-Hofmann and Schlatter 1986), without providing an explanation for this finding.…”

GA Strategy for Variable Selection in QSAR Studies: GA-Based Region Selection for CoMFA Modeling

“…Also, as shown in Figure C, the contributions of positions C-3 and C-7 to the binding affinity are larger than those of positions C-2 and C-8. This structural requirement is also consistent with the results in the previous studies. , …”

“…In Figure , it was shown that the important regions are located around the lateral positions of the PCDF molecules. In the previous structure−activity relationship study, it was proposed that the chlorine atoms at a lateral position are an advantage for the binding affinity of the PCDF molecules. − These structural requirements are consistent with the result of this CoMFA modeling. The coefficient contour map in Figure clearly indicates the corresponding regions, and the utility of CoMFA with GARGS is validated.…”

Synthesis of Polybrominated Diphenyl Ethers and Their Capacity to Induce CYP1A by the Ah Receptor Mediated Pathway

“…In conclusion, PBDEs contribute to the total "dioxin-like" activity of environmental samples, although their activity is much less than that of potent HACs such as PCDDs, PCDFs, and coplanar PCBs. Only a subset of the PBDEs induces EROD activity, as is true also for PCDDs (56), PCDFs (57), PCBs (43,58,59), PBBs (60), polychlorinated naphthalenes (PCNs) (61), and polycyclic aromatic hydrocarbons (PAHs) (62,63). The most active PBDE congeners are more potent than mono ortho PCBs (43,58,59), with REPs similar to those observed for PCNs (60) and PAHs (61,62).…”

Comparative toxicity of four chlorinated dibenzo-p-dioxins (CDDs) and their mixture

“…Several other studies have, however, been conducted using mixtures of CDDs and/or chlorinated dibenzofurans (CDFs) to examine different biological or toxicological endpoints. Most of these studies also suggest an additive action of the individual compounds Weber et al 1985;Mason et al 1985;Pluess et al 1988). However, competitive effects of CDDs and CDFs on enzyme induction and immune toxicity have been reported in one study (Rizzardini et al 1983) as well as in a 51/2 week feeding study with a mixture of CDDs and CDFs obtained by extraction of particulate matter from a municipial waste incinerator (Suter-Hofmann and Schlatter 1986), without providing an explanation for this finding.…”