We examined whether serum cholesterol reduction alters the lesional composition of atherosclerotic plaques. To reduce serum cholesterol levels, we gave pravastatin sodium, a 3-hydroxy-3-methylglutaryl Coenzyme A reductase inhibitor, to mature Watanabe heritable hyperlipidemic rabbits, an LDL receptor-deficient animal model, for 48 weeks. Atherosclerotic lesions were immunohistochemically and conventionally stained and each lesional component area was measured by a color image analyzer. Compared with those of a placebo group, serum LDL cholesterol levels were reduced by 22% (P<.05). Data for atherosclerosis indicated a significant decrease in percent of surface lesion area (26% reduction) and in intimal thickening (30% reduction) in the abdominal aorta, as well as in coronary stenosis (29% reduction). Data for lesional composition indicated a significant decrease in the percent area of macrophage plus extracellular lipid deposits in aortic lesions (32% reduction) and coronary lesions (45% reduction). A significant increase was observed in the percent area of collagen in aortic lesions and in the percent area of smooth muscle cells in coronary lesions. The plaques seemed to become stable lesions as a result of pravastatin treatment. In conclusion, a long-term reduction of serum LDL cholesterol reduced lipid-related lesional components, in addition to suppressing the progression of established atherosclerosis.

We report a systematic study on nanophase-separated structures from block-and graft-type supramacromolecules via acid-base complexation, where supramacromolecules are termed as supramolecules composed of a pair of macromolecules with complementary noncovalent bonding moieties. Block-or graft-type supramacromolecules were built up by blending component polymers, that is, sulfonic acid-terminated polystyrene (PS-SO 3 H, M n ) 19 k) or polystyrene-block-poly(4-styrenesulfonic acid) (PS-P(SSO 3 H), M n )23k) with primary amine-terminated polyisoprene (PI-NH 2 , M n ) 17 k). Self-assembled nanostructures of the blends were confirmed complementarily by transmission electron microscopy and small-angle X-ray scattering. At larger acid/base molar ratio, the blends show comparatively ordered nanophase-separated structures without macrophase-separated large PS domain. Morphological transition controlled by composition has occurred in the blends of PS-P(SSO 3 H)/PI-NH 2 as ordinary block copolymers show, though the blends of PS-SO 3 H/PI-NH 2 showed macrophase separation at excess ratio of PI-NH 2 to PS-SO 3 H. The difference in composition dependence of morphology between two blend series is resulted from stoichiometric effects of sulfonic acid vs amine. Therefore, PS-P(SSO 3 H) is more useful to build up various supramacromolecular complexes with PI-NH 2 than PS-SO 3 H just by changing the molar ratios of component polymers, that is, multiple noncovalent bonding can be found more advantageous, resulting in conforming graft-type supramacromolecules, not a block-type supramacromolecule from PI-NH 2 and PS-SO 3 H.

We have developed a computer simulation code for three-dimensional viscous flow in turbomachinery based on the time-averaged compressible Navier–Stokes equations and a low-Reynolds-number k–ε turbulence model. It is described in detail in this paper. The code is used to compute the flow fields for two types of rotor (a transonic fan NASA Rotor 67 and a transonic axial compressor NASA rotor 37), and numerical results are compared to experimental data based on aerodynamic probe and laser anemometer measurements. In the case of Rotor 67, calculated and experimental results are compared under the design speed to validate the code. The calculated results show good agreement with the experimental data, such as the rotor performance map and the spanwise distribution of total pressure, total temperature, and flow angle downstream of the rotor. In the case of Rotor 37, detailed comparisons between the numerical results and the experimental data are made under the design speed condition to assess the overall quality of the numerical solution. Furthermore, comparisons under the part-speed condition are used to investigate a flow field without passage shock. The results are well predicted qualitatively. However, considerable quantitative discrepancies remain in predicting the flow near the tip. In order to assess the predictive capabilities of the developed code, computed flow structures are presented with the experimental data for each rotor and the cause of the discrepancies is discussed.

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