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Notes: We have confirmed that more female subjects than male subjects evaluate male body odor as significantly unpleasant. Through an investigation on sexual differentiation in sensitivity to male body odor, we concluded that one of the volatile steroids, androstenone, had two effects on female olfactory sense. First, female subjects perceived androstenone itself to be more unpleasant than male subjects. Second, for only female subjects, androstenone, at a concentration of one-tenth of detection threshold, enhanced the intensity and unpleasantness of body-odor constituents such as short-chain fatty acids.

Notes: A new protective film, Tb-SiO2, was developed to increase the lifetime of TbFeCo magneto-optical disks. Since Tb, a rare-earth metal, is quite easily oxidizable, an efficient protective layer is essential to assure the stability of magneto-optical disks. Given that vacuum-deposited SiO2 film acts as an oxidation-inducing layer, unlike SiO2 on a thermally oxidized silicon wafer, we invented a new protective film, Tb-SiO2, in which Tb is intended to trap active oxygen in the vacuum-deposited SiO2. The results were excellent and we estimate the lifetime of TbFeCo disks with Tb-SiO2 as an underlayer and overlayer, at more than 20 years at 40 °C, 90% relative humidity. The properties and protection effects of Tb-SiO2 are described.

Notes: The dependence of perpendicular magnetic anisotropy on temperature and composition has been investigated for various (Fe,Co)–rare-earth amorphous binary alloy films prepared by evaporation. The temperature dependence of the perpendicular magnetic anisotropy is proportional to the third power of the rare-earth sublattice magnetization. The perpendicular magnetic anisotropy consists of two terms related to concentration. One is proportional to the rare-earth content and the other to its square. Both terms can be explained by a large rare-earth single-ion anisotropy.

Notes: Relationship between the changes in compositional short-range order (CSRO) and field-induced anisotropy (Ku) was studied in the amorphous zero-magnetostrictive alloy of composition Co58.3Fe4.7Ni10Si11B16, which has an appropriate Curie temperature (Tc) and high-crystallization temperature. Resistivity measurements after quenching from preannealing temperature (TQ) show that the reversible CSRO can be separated from the nonreversible topological short-range order. Resistivity change (Δρ/ρ) and Ku change (ΔKu) were measured isothermally at 250 °C (〈Tc) and also isochronally in the sample quenched from TQ. It was found that [d/Δρ/ρ)/dt]/[d(ΔKu )/dt] is constant and the higher TQ is, the larger both d(Δρ/ρ)/dt and d(ΔKu )/dt are. The approximate theory of the kinetics of both CSRO and Ku were given and it can explain the observed changes in Δρ/ρ and ΔKu. By assuming that the tail of the distribution of sizes of the interstitial sites in the soft-sphere dense random-packing model can act as a vacancylike defect, the formation mechanism of ΔKu which can explain the observed experimental facts was proposed.

Notes: Abstract: Biochemical characteristics of brain microsomal membranes were examined before and after the brightness-discrimination learning tasks in rats that were fed either safflower oil (α-linolenate-deficient) or perilla oil (α-linolenate-sufficient) diets. We detected small changes in the chain elongation system for polyunsaturated fatty acids in microsomes, whereas no significant difference was detected in the inositol trisphosphate-induced calcium release and ATP-induced calcium uptake profiles of microsomes between the two dietary groups. The calcium ion-induced aggregation rate of microsomes was determined in both groups. We found that the aggregation rate of microsomes in the safflower oil group was significantly greater than that in the perilla oil group. The difference in susceptibility of microsomal membrane phospholipids to phospholipase A2 between the groups was obvious, and the amount of released fatty acids by phospholipase A2 from the perilla oil group microsomes was nearly half of that from the safflower oil group microsomes after the learning task. Susceptibility of sialic acids on the brain microsomal membranes to exogenous sialidase was different only after the learning task in the safflower and perilla oil groups. These results suggest that the biochemical characteristics of membrane surfaces of brain microsomes are affected significantly by the learning task itself in a dietary oil-dependent manner.

Notes: 1. This study was undertaken to examine the possibility that the level of angiotensin-converting enzyme (ACE) increases in vascular tissue, and that this may participate in the pathogenesis of hypertension in spontaneously hypertensive rat (SHR).2. In SHR, at the established hypertensive stage, the prolonged antihypertensive effect induced by a single oral dose of spirapril was closely correlated to the long-lasting inhibition of ACE in aortae and mesenteric arteries. In contrast, ACE in plasma, lung, heart and kidney recovered from inhibition faster than in vessels.3. Prolonged daily oral treatment of SHR with spirapril, initiated at the age of 8 weeks and continued for 8 weeks, prevented the development of hypertension with concomitant decrease in aortic ACE activity. Blood pressure continued to be suppressed after the drug was withdrawn, as did the aortic ACE activity.4. Spontaneously hypertensive rats developed hypertension with age as well as with the increase in aortic ACE activity which became higher with age than that of Wistar-Kyoto (WKY) normotensive control rats. On the contrary, ACE activity in plasma and lung of SHR was substantially lower than that of WKY at any age from 4 to 20 weeks old. Brain ACE activity of SHR did not differ from that of WKY at any age. Aged SHR showed the lower enzyme activity in the kidney compared with that of age-matched WKY.5. Our results support the hypothesis that increased vascular ACE may play an essential role in the development and maintenance of hypertension in SHR.

Notes: The inhibition of angiotensin II (AngII) by use of angiotensin converting enzyme (ACE) inhibitor or AngII receptor blocker is effective for prevention of the progression of renal diseases including IgA nephropathy (IgAN). AngII plays a variety of biological roles via AngII receptors. Through AngII type 1 receptor (AT1R), AngII induces vasoconstriction, cellular proliferation, extracellular matrix production and fibrosis, while it leads vasodilatation, apoptosis and inhibition of cell proliferation through AngII type 2 receptor (AT2R). Recent studies showed the local production of AngII in many tissues including the heart, vessel and kidney, suggesting that local AngII may be more important than circulating AngII in tissue injury. AngII is generated from angiotensin I by ACE or ACE independent pathway, such as chymase which is a serine protease. Since chymase was shown to be synthesized 80% of AngII in human heart, chymase also may play an important role in converting to AngII in the kidney. Although it was reported that ACE was produced in renal tissue, the localization of chymase and AngII receptors is unclear in the human kidney. To research the local renin-angiotensin system in renal tissue of patients with IgAN, we localized chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA by in situ hybridization and investigated the relationship between the expression of these mRNAs and tissue injury. Fresh frozen sections of renal tissue from 21 patients with IgAN were examined. The sections were fixed with 4% paraformaldehyde and hybridized with the digoxigenin (DIG)-labelled oligonucleotide probes for chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA. Using anti-DIG antibody, immunohistochemistry was performed to visualize the DIG-labelled probe. Colour was developed by reaction with H2O2 and 3,3′diaminobenzidine/=tetrahydrochloride. As identifying the exact locations of the cells positive for chymase mRNA, ACE mRNA and AngII receptor mRNA, we stained using periodic acid-Schiff after in situ hybridization. We classified the histological grading of the glomerular and tubulointerstitial injury. Two to five glomeruli were analysed in each biopsy tissue and the degree of injury in each glomerulus was graded from 1 to 3 based on the proportion of the lesion in the sectioned areas of each glomerulus. In the tubulointerstitium, three to five fields of cortical interstitium in each section were examined under low magnification (×200). In each designated field, we determined the degree of tubular atrophy and interstitial fibrosis from grade 1 to 3. In situ hybridization showed that the signals of chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA were observed in mesangial cells, glomerular epithelial cells, cells of the Bowman’s capsule, cells of crescent, tubular epithelial cells and some infiltrating mononuclear cells. In the glomeruli, the percentage of cells positive for chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA per glomerulus decreased as the glomerular injury progressed. Chymase mRNA and ACE mRNA were diffusely expressed in the glomeruli with mild injury. The expression significantly increased in the area of mesangial cells proliferation without mesangial matrix expansion, however, it decreased as the glomerular lesion progressed. In the tubulointerstitium, the expression of chymase mRNA, ACE mRNA and AT1R mRNA positively correlated with the degree of tubulointerstitial injury. The expression of AT2R became significantly strongest in moderate injury lesions and diminished in severe lesion. All mRNAs were highly expressed in atrophic tubuli. We also examined the relation of the cells positive for chymase mRNA and ACE mRNA on serial sections. Most cells positive for chymase mRNA also stained for ACE mRNA in the glomeruli and the tubulointerstitium. In situ hybridization for AT1R mRNA and AT2R mRNA in serial sections showed that some cells produced the both mRNAs, while other cells expressed only AT1R mRNA or AT2R mRNA. In the present study, we identified that chymase, ACE and AngII receptor were synthesized in renal tissue with IgAN. Our results suggest that AngII was generated by local ACE and ACE independent pathway (chymase) and that the regulation of local renin angiotensin system in renal tissue was different between glomerulus and tubulointerstitium. Local renin angiotensin system may contribute the progression of tissue injury in IgAN.