Title of article :
Relationship between Surface Properties and Cellular Responses to Crystalline Silica: Studies with Heat-Treated Cristobalite
Author/Authors :
Fubini، Bice نويسنده , , Zanetti، Giovanna نويسنده , , Altilia، Serena نويسنده , , Tiozzo، Roberta نويسنده , , Lison، Dominique نويسنده , , Saffiotti، Umberto نويسنده ,
Issue Information :
ماهنامه با شماره پیاپی سال 1999
Pages :
-736
From page :
737
To page :
0
Abstract :
A fibrogenic sample of cristobalite dust, CRIS (crystalline silica of mineral origin), was heated to 1300 °C (CRIS-1300) to relate induced physicochemical modifications to cytotoxicity. Heating did not affect dust micromorphology and crystallinity, except for limited sintering and decreased surface area of CRIS-1300. Thermal treatments deeply affected surface properties. Electron paramagnetic resonance showed surface radicals progressively annealed by heating, mostly disappearing at >800 °C. Surface hydrophilicity or hydrophobicity, evaluated with water vapor adsorption, still showed some hydrophilic patches in CRIS-800, but CRIS-1300 was fully hydrophobic. Heating modified the biological activity of cristobalite. Cytotoxicity, tested on proliferating cells of the mouse monocyte macrophage cell line J774, showed that CRIS was cytotoxic and CRIS-800 was still cytotoxic, but CRIS-1300 was substantially inert. Cytotoxicity of CRIS to the rat lung alveolar epithelial cell line, AE6, as measured by colony forming efficiency, was greatly reduced for CRIS-800 and eliminated for CRIS-1300. The rate oflactate dehydrogenase release by rat alveolar macrophages was lowered for CRIS-800, and release was completely inactivated for CRIS-1300. The absence of surface radicals and the onset of hydrophobicity may both account for the loss of cytotoxicity upon heating. Differences observed between CRIS-800 and CRIS-1300, both fully deprived of surface radicals, indicate that hydrophobicity is at least one of the surface properties determining the cytotoxic potential of a dust.
Keywords :
Computational methods in statistical physics , Nonlinear dynamics , Theory , computer simulation , modeling
Journal title :
Chemical Research in Toxicology
Serial Year :
1999
Journal title :
Chemical Research in Toxicology
Record number :
25127
Link To Document :
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