A sphere-type fully substituted oligosaccharide-β-alanine-poly(lysine) dendrimer having a sharp molecular weight distribution was synthesized. Sphere-type poly(lysine) dendrimers were prepared using 1,4-diaminobutane as an initiator core and N,N′-bis(tert-butyloxycarbonyl)-L-lysine as a branching unit. β-Alanine was bound to the poly(lysine) dendrimer generation 3 to form β-alanine-poly(lysine) dendrimer generation 3, which has 16 terminal amino groups on its surface. A series of sphere-type oligosaccharide-β-alanine-poly(lysine) dendrimers were obtained by binding such an oligosaccharide as maltose, lactose, cellobiose, maltotriose, or a mixture of lactose and maltose to the surface of the β-alanine-poly(lysine) dendrimer scaffolding by reductive amination using the borane-pyridine complex. Oligosaccharide-β-alanine-poly(lysine) dendrimers having 32 oligosaccharide residues were obtained in high yields. NMR and MALDI-TOF mass measurements revealed that the oligosaccharide-polypeptide dendrimers have a monodispersed molecular weight distribution, the molecular weight of which was 13 418.36, 13 472.50, and 13 507.28 g/mol for cellobiose, maltose, and lactose, respectively, indicating that a complete substitution of the amino group by the oligosaccharide occurred.
The widths of slit diaphragms in rat glomeruli were quantitatively measured on electron micrographs obtained by the rapid-freezing and freeze-substitution (FS) fixation method and compared to those prepared by conventional chemical fixation procedures, such as tannic acid, glutaraldehyde and osmium tetroxide (TGO) or glutaraldehyde and osmium tetroxide (GO) fixation. When fixed by FS using 2% osmium tetroxide, glomerular slit diaphragms had widths of 33.8 +/- 3.6 nm, but when fixed by TGO or GO they had widths of 47.0 +/- 4.3 and 48.7 +/- 5.5 nm, respectively. The width of slit diaphragms was significantly narrower after cryofixation than after conventional TGO or GO fixation (P less than 0.001). Similarly, the distance between neighboring foot processes at 50 nm from slit diaphragms was significantly narrower after cryofixation (P less than 0.001). The widths were 98.6 +/- 17.1 nm after TGO fixation, 122.0 +/- 29.3 nm after GO fixation and only 54.8 +/- 18.7 nm after FS fixation. These foot processes were significantly broader after FS fixation. The foot processes were 179.2 +/- 59.4 nm in breadth after TGO fixation (P less than 0.001), 188.8 +/- 78.2 nm after GO fixation (P less than 0.01) and 235.1 +/- 87.2 nm after FS fixation. These results suggest that the cytoplasm of foot processes shrinks when the tissue is prepared by conventional chemical fixation methods, and that the broadening of slit diaphragms is an artifact separation of the margins of adjacent foot processes due to shrinkage. We propose that TGO fixation alters the structure of slit diaphragms by causing them to shrink.
In this paper, surface degradation of hair is reviewed. Surface properties such as hydrophobicity and surface friction change as surface structures of hair fiber, that is, 18-methyleicosanoic acid (18-MEA) and epicuticle, degrade. Comparison of contact angle and amount of 18-MEA from root to tip of the sampled hair fibers clarified the contribution of not only 18-MEA but also epicuticle to surface properties. It was found that chemical treatment by itself, such as bleaching, is not enough to cause complete loss of hydrophobic nature even after 18-MEA is removed. Additional weathering processes, such as repeatedly shampooing, are required. A technology for the deposition of a persistent hydrophobicity to bleached and weathered hair surfaces using 18-MEA is presented. Combination of 18-MEA with specific cationic surfactants (Stearoxypropyldimethylamine: SPDA) made the bleached and weathered hair surface hydrophobic, and its hydrophobicity was maintained even after shampooing. Characterization of adsorbed layers of 18-MEA/SPDA on a mica surface, as a possible hydrophilic surface model, was performed using atomic force microscopy (AFM) and angle-resolved X-ray photoelectron spectroscopy (AR-XPS). The effects of the anteiso-branch moiety of 18-MEA to create a persistent hydrophobicity with 18-MEA/SPDA were investigated using controlled AFM. It was revealed that the anteiso-branch moiety of 18-MEA in the 18-MEA/SPDA system produces a persistent hydrophobicity by providing higher fluidity to the upper region of the 18-MEA/SPDA layer. The contribution to hair beauty and sensory feeling as one of the practical functions of the hair surface is described in this paper. The hydrophobic nature of the hair surface reduces surface friction in a wet state, which reduces hair disorder alignment. It is also revealed that the moisturized or dried out feeling strongly depends on the hair shape (meandering and diameter) which depends on hair surface properties in a wet environment.
and MMP-9 activities from its lowest concentration, and MMP-1 and MMP-2 at its higher concentrations, which implies a greater protective effect on elastin. It dramatically increased the expression of types I, III, and V collagens, and elastin, fibrillin-1, and fibrillin-2 in dermal fibroblasts. The effects were similar to those of ascorbic acid. This is the first report identifying xanthohumol's potential to improve skin structure and firmness: it simultaneously inhibits the activities of elastase/MMPs and stimulates the biosynthesis of fibrillar collagens, elastin, and fibrillins.pp. 133-145 Comparison of hydration, tyrosinase resistance, and antioxidant activation in three kinds of pearl powders by
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