RESUMEN
Bovine caudal motion segments were used to investigate the loss of load-bearing ability under both quasi-static and cyclic loading. 80 motion segments dissected from 41 bovine tails were subjected to quasi-static and cyclic compression...
Asunto(s)
Disco Intervertebral , Desplazamiento del Disco Intervertebral , Enfermedades de la Columna VertebralRESUMEN
Bovine caudal motion segments were used to investigate the intrinsic failure strenght of the intect intervertebral disc under internal hydrostatic pressure...
Asunto(s)
Humanos , Presión Hidrostática , Disco IntervertebralRESUMEN
The collagen structure of isolated and in situ liver granuloma from Swiss Webster mice infected with Schistosoma mansoni was sequentially and three-dimensionally analyzed during different times of infection (early acute, acute, transitional acute-chronic, and chronic phases) by laser scanning confocal microscopy and electron scanning variable vacuum microscopy. The initial granuloma structure is characterized by vascular collagen residues and by anchorage points (or fiber radiation centers), from where collagenous fibers are angularly shed and self-assembled. During the exudative-productive stage, the self-assembly of these fibers minimizes energy and mass through continuous tension and focal compression. The curvature or angles between collagen fibers probably depends on the fibroblastic or myofibroblastic organization of stress fibers. Gradually, the loose unstable lattice of the exudative-productive stage transforms into a highly packed and stable architecture as a result of progressive compactness. The three-dimensional architecture of granulomas provides increased tissue integrity, efficient distribution of soluble compounds and a haptotactic background to the cells