Quantitative gait evaluation of hip diseases using principal component analysis

The measurement of five gait parameters, namely, joint angular displacement of lower extremities, floor reaction forces, trajectory for a point of force application, temporal factor and distance factor has been performed with ease and high speed using mini-computer on-line real-time processing. Gait data of 211 patients with hip diseases was normalized, quantified and summarized by the principal component analysis. A 'gait evaluation plane' was formed according to the results obtained by the principal component analysis. The gait evaluation using the plane was compared with clinical conditions of patients, and it was evident that this system can evaluate the recovery of the gait by treatment.     

Demonstration of a novel sulfotransferase in fetal bovine serum, which transfers sulfate to the C6 position of the GalNAc residue in the sequence iduronic acid alpha1-3GalNAc beta1-4iduronic acid in dermatan sulfate.

A novel sulfotransferase activity was discovered in fetal bovine serum using pig skin dermatan sulfate as an acceptor and [35S]3'-phosphoadenosine 5'-phosphosulfate as a sulfate donor. The enzyme was separated from chondroitin:GalNAc 6-O-sulfotransferase by chromatographic techniques. Enzymatic analysis of the reaction products demonstrated that the enzyme transferred sulfate to the C6 position of the GalNAc residue in the sequence -iduronic acid alpha1-3GalNAc beta1-4iduronic acid-. Thus, the enzyme has been identified as a hitherto unreported dermatan sulfate:GalNAc 6-O-sulfotransferase. The finding is in sharp contrast to the current concept that in dermatan sulfate biosynthesis GalNAc 4-O-sulfation is a prerequisite for iduronic acid formation by C5 epimerase.     

Identification of cell-binding site of angiomodulin (AGM/TAF/Mac25) that interacts with heparan sulfates on cell surface.

Angiomodulin (AGM/TAF/mac25) is a 30-kDa glycoprotein that was identified as an integrin-independent cell adhesion protein secreted by human bladder carcinoma cells. AGM is highly accumulated in small blood vessels of tumor tissues. In the present study, we attempted to identify the cell surface receptor and the cell-binding site of AGM using ECV-304 human vascular endothelial cells and BALB/c3T3 mouse fibroblasts. Heparin, heparan sulfate, and dextran sulfate, but not chondroitin sulfate, inhibited both adhesion of the two cell lines to AGM-coated plates and binding of AGM to these cells. Treatment of cells with heparinase, but not chondroitinase, inhibited both cell adhesion to AGM and AGM binding to cells. These results strongly suggested that heparan sulfates are the major receptor for AGM. Furthermore, we determined a 20-amino acid sequence within AGM molecule as its major cell-binding site. The synthetic peptide for the cell-binding sequence showed cell adhesion activity comparable to that of AGM, and the activity was inhibited by heparin and heparan sulfate. The peptide competitively inhibited cell adhesion to AGM and the binding of AGM to cells. These results indicated that AGM binds to cells through interaction of the identified cell-binding sequence with heparan sulfates on cell surface. It was also found that the heparan sulfate-binding peptide inhibited the formation of capillary tube-like structures of vascular endothelial cells in culture.