title: Silica and silicates in femoral lymph nodes of barefooted people in Ethiopia with special reference to elephantiasis of the lower legs.
abstract: Electron microscopy of femoral lymph nodes of barefooted Ethiopians show the presence of numerous particles of colloid-size and electron-density in the lysosomes of the macrophages in the gland. On diffraction analysis, the particles are found to be amorphous. Elemental microanalysis of the X-ray spectrum indicate the predominance of Si, Al and Fe. In elephantiasics some particles contain silicon alone, presumably silica. The distribution of the Al/Si ratios of the particles in subjects with elephantiasis of the lower legs show a difference from that of non-elephantiasics which is statistically "highly significant" at p less than 0.001. The importance of this as a possible aetiological factor in the disease is discussed. The hypothesis that the disease is discussed. The hypothesis that the disease is a silicosis of the peripheral lymphatics of the lower limbs is supported by the present study.
mesh_terms: D000535:Aluminum / Q000032:analysis; D004604:Elephantiasis / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D005002:Ethiopia; D006801:Humans; D007866:Leg; D008198:Lymph Nodes / Q000032:analysis* / Q000648:ultrastructure; D008209:Lymphedema / Q000378:metabolism*; D008247:Lysosomes / Q000032:analysis / Q000648:ultrastructure; D008264:Macrophages / Q000032:analysis / Q000648:ultrastructure; D008854:Microscopy, Electron; D012824:Silicic Acid / Q000032:analysis; D012822:Silicon Dioxide / Q000032:analysis*; D013848:Thigh
chemical_list: D012824:Silicic Acid; D012822:Silicon Dioxide; D000535:Aluminum