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'Calcification' in keywords Facet   section ZfN Section C  [X]
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1983 (1)
1980 (1)
1Author    H. J. Tochon-Danguy, G. Boivin, M. Geoffroy, C. Walzer, C. A. BaudRequires cookie*
 Title    Physical and Chemical Analyses of the Mineral Substance during the Development o f Two Experimental Cutaneous Calcifications in Rats: Topical Calciphylaxis and Topical Calcergy  
 Abstract    In subcutaneous calcinoses induced in rats by topical calciphylaxis and topical calcergy, the ultrastructural aspects related to the evolution o f calcified deposits were previously described. In the present study by m eans o f X-ray diffraction, infrared spectrometry and electron spin resonance, different biophysical analyses are performed on the mineral substance deposited during developm ent o f calciphylaxis and calcergy. A rapid evolution o f the calcium phosphate deposits into hydroxyapatite was noticed along the first 20 days o f the calcinoses; from then, there is no important m odification even at the later stages, and the characteristics o f the mineral substance are mostly sim ilar to that o f bone tissue. The concentration o f trace elem ents such as M g2+ and F e2+, is found higher in cutaneous calcinoses than in bone tissue. 
  Reference    Z. Naturforsch. 38c, 135 (1983); received July 10 1982 
  Published    1983 
  Keywords    Calcification, Calciphylaxis, Calcergy, Apatite, ESR 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0135.pdf 
 Identifier    ZNC-1983-38c-0135 
 Volume    38 
2Author    H. Newesely, R. Hosemann, B. U. TherRequires cookie*
 Title    Kollagen-Einschlußverbindungen Inclusion Compounds of Collagen  
 Abstract    Small angle X-ray diagrams o f native collagen o f rat tail treated with phospho tungstic acid or mercury chloride or cobalt-and uranyl-nitrate, osmiumoxide or hydroxy apatite show the same characteristic new reflections and reflection lines. The only remarkable difference exists between fibers treated under stress or relaxed. These experiments give new evidence for the paracrystallini-ty of collagen. More than 1 0 0 parallel aligned ca. 40 A thick octafibrils consist o f 670 A long micro­ paracrystals with 5 ca. 25 A thick soft segment layers. In these soft segments the holes o f the octafi­ brils build up a lattice o f vacancies with lattice cells o f 38,5x35x135 A3 length. The above mention­ ed molecules penetrate from the lateral sides through the soft segments into these vacancies build­ ing up complexes with peptide groups of collagen. Under stress only a small amount o f vacancies is occupied, statistically distributed over the vacancy-lattice, because the soft segments of the octa­ fibrils are constricted. Without stress about 10 to 25% o f the octafibrils within one paracrystal are filled up with sediments in the soft regions. With increasing precipitation finally 500 A long nee­ dles are formed of the inclusive material as detected by Höhling with the electron microscope in collagen of turkey tendon. The importance o f the paracrystalline collagen model is emphasized to understand the biological process like the mineralisation o f collagen and ^-keratin in organism or the activity of bone apatite in exchanging calcium ions. 
  Reference    Z. Naturforsch. 35c, 177—187 (1980) 
  Published    1980 
  Keywords    Microparacrystals, Calcification, Octafibrils, Hydroxyl Apatite, Collagen Inclusion Compounds 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0177.pdf 
 Identifier    ZNC-1980-35c-0177 
 Volume    35