Tissue specificities of protease A-like esteroprotease in male mice

An esteroprotease hydrolyzing p-tosyl-L-arginine methyl ester (TAME) has been purified to homogeneity from male mice submandibular glands by the ammonium sulphate precipitation, Sephadex gel chromatography and DEAE-cellulose chromatography. The enzyme was shown as a single chain acidic protein (pI = 5.7) with the molecular weight of 27.5 K and evidence was obtained to reveal that it was similar to protease A. Using this enzyme as antigen we prepared anti-TAMEase antibody. The immunoblotting studies on tissue specificity using 20 different tissues from male mice revealed that cross-reactivities with anti-TAMEase antibody were observed in the crude extract from the sublingual gland, parotid gland and pancreas. The species specificity studies with the submandibular glands of 7 different species indicated that only the crude extract from rat submandibular glands reacted against anti-TAMEase antibody but it exerted a low TAMEase activity.     

Fast,cell-resolution,contiguous-wide two-photon imaging to reveal functional network architectures across multi-modal cortical areas

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Local mechanical anisotropy in human cranial dura mater allografts.

Human cranial dura mater (CDM) allograft's success as a repair biomaterial is partly due to its high mechanical strength, which facilitates its ability to form water-tight barriers and resist high in-vivo mechanical loads. Previous studies on CDM allograft mechanical behavior used large test specimens and concluded that the allograft was mechanically isotropic. However, we have quantified CDM microstructure using small angle light scattering (SALS) and found regions of well-aligned fibers displaying structural symmetry between the right and left halves (Jimenez et al., 1998). The high degree of fiber alignment in these regions suggests that they are mechanically anisotropic. However, identification of these regions using SALS requires irreversible tissue dehydration, which may affect mechanical properties. Instead, we utilized CDM structural symmetry to estimate the fiber architecture of one half of the CDM using computer graphics to flip the SALS fiber architecture map of the corresponding half about the plane of symmetry. Test specimens (20 mm x 4 mm) were selected parallel and perpendicular to the preferred fiber directions and subjected to uniaxial mechanical failure testing. CDM allografts were found to be locally anisotropic, having an ultimate tensile strength (UTS) parallel to the fibers of 12.76 +/- 1.65 MPa, and perpendicular to the fibers of 5.21 +/- 1.01 MPa (mean +/- sem). These results indicate that uniaxial mechanical tests on large samples used in previous studies tended to mask the local anisotropic nature of the smaller constituent sections. The testing methods established in this study can be used in the evaluation of new CDM processing methods and post-implant allograft mechanical integrity.