Background and Purpose-We evaluated several hemodynamic parameters for the prediction of rupture in a data set of initially unruptured aneurysms, including aneurysms that ruptured during follow-up observation. Methods-Aneurysm geometry was extracted from CT angiographic images and analyzed using a mathematical formula for fluid flow under pulsatile blood flow conditions. Fifty side-wall internal carotid posterior communicating artery aneurysms and 50 middle cerebral artery bifurcation aneurysms of medium size were investigated for energy loss, pressure loss coefficient, wall shear stress, and oscillatory shear index. During follow-up observation, 6 internal carotid posterior communicating artery and 7 middle cerebral artery aneurysms ruptured (44 and 43 remained unruptured, respectively, with the same location and a similar size as the ruptured cases). Results-A significant difference in the minimum wall shear stress between aneurysms that ruptured and those that remained unruptured was noted only in internal carotid artery aneurysms (PϽ0.001). Energy loss showed a higher tendency in ruptured aneurysms but statistically not significant. For pressure loss coefficient, a significant difference was noted in both internal carotid artery (Pϭ0.0046) and middle cerebral artery (PϽ0.001) aneurysms. Conclusions-Pressure loss coefficient may be a potential parameter to predict future rupture of unruptured aneurysms. (Stroke.

The two subunit types of human liver ferritin were purified to homogeneity. Both subunits reassembled in a well-defined manner and formed spherical particles that resembled natural apoferritin in electron micrographs. Affinity chromatography methods were employed to obtain preparations of antibodies that interacted exclusively either with the H or with the L polypeptides, demonstrating that distinct immunological properties may be ascribed to each subunit of ferritin. The amino acid compositions of the subunits were similar, but the larger H subunit had fewer leucine, phenylalanine, and arginine residues. It is therefore improbable that H subunits undergo proteolytic processing and are precursors for L subunits. Circular dichroism data indicated that homopolymers assembled from L-type subunits had substantially more ordered secondary structures and greater alpha-helical contents than their H counterparts. Small differences in the environment of tryptophan residues were evident from fluorescence spectra of each homopolymer. In isoelectric focusing experiments reassembled H or L homopolymers migrated as families of proteins within discrete pI ranges which are probably representative of subpopulations of each subunit type. The H homopolymer focused at lower pI's than the L component. These data substantiate the contention that both subunits are authentic polypeptide moieties of ferritin with some common structural features, but the results also underscore prominent dissimilarities in their properties.

Three composites composed of the cobalt terpyridine complex [Co II (MeO-terpy) 2 ] and the diblock copolypeptide amphiphiles 1 and 2 or the polypeptide 3 (including glutamic acid and leucine) were prepared. Supramolecular structures such as rectangular morphologies were obtained from composites of 1 and 2. A perfectly reversible reverse spin transition was successfully generated in the case of composites made with 1.

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