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1.
The inhibitory effects of 102 methanol extracts of 40 mycelia, 9 culture fluids, and 53 fruiting bodies of 40 strains of Ganoderma lucidum on 5-reductase were investigated. The methanol extract of the fruiting body of each strain was found to show the strongest 5-reductase inhibitory activity among the extracts tested.  相似文献   
2.
The effects of 120 methanol extracts prepared from bark and heartwood of 69 types of Japanese wood on the melanin production of B16 melanoma cells were examined. The melanin content of B16 melanoma cells was determined spectrophotometrically at 405nm. The extracts were also examined for their effects on cell viability. We found that the methanol extracts of Fagus crenata (buna, wood, 100μg/ml), Sapium sebiferum (Nankinhaze, wood, bark, 10μg/ml), and Zelkova serrata (keyaki, wood, 10μg/ml) greatly inhibited the melanin production of B16 melanoma cells without significant cytotoxicity. However, these extracts did not inhibit tyrosinase activity at the concentration of 100μg/ml. These findings indicate that the depigmenting mechanism of these extracts involves the suppression of some pigmenting signals in stimulating melanogenesis rather than the inhibition of tyrosinase activity. Part of this study was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, Japan, March 2003  相似文献   
3.
Pleurotus citrinopileatus Singer has recently become a popular delicacy in East Asian countries. We prepared a methanol extract, soluble fractions from the methanol extract, and a hot water extract of the fruiting bodies of P. citrinopileatus. The biological activities such as melanin biosynthesis inhibition, tyrosinase inhibition, antioxidant activities [1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, oxygen radical absorbance capacity (ORAC), and superoxide dismutase (SOD)-like activity], antibacterial activities, and antihyaluronidase activities of these extracts were evaluated. We found that the n-hexanesoluble, diethyl ether-soluble, and ethyl acetate-soluble fractions exhibited melanin biosynthesis inhibition in B16 melanoma cells, as well as antioxidant (ORAC) and antibacterial activities. However, the n-butanol-soluble and water-soluble fractions and the methanol and hot water extracts exhibited antioxidant (DPPH radical scavenging, SOD-like activity) and antihyaluronidase activities. These results indicate that the fruiting bodies of P. citrinopileatus have the potential to be used as an ingredient in skin cosmetics.  相似文献   
4.

Background

To investigate plant hybrid sterility, we studied interspecific hybrids of two cultivated rice species, Asian rice (Oryza sativa) and African rice (O. glaberrima). Male gametes of these hybrids display complete sterility owing to a dozen of hybrid sterility loci, termed HS loci, but this complicated genetic system remains poorly understood.

Results

Microspores from these interspecific hybrids form sterile pollen but are viable at the immature stage. Application of the anther culture (AC) method caused these immature microspores to induce callus. The segregation distortion of 11 among 13 known HS loci was assessed in the callus population. Using many individual calli, fine mapping of the HS loci was attempted based on heterozygotes produced from chromosome segment substitution lines (CSSLs). Transmission ratio distortion (TRD) from microspores was detected at 6 of 11 HS loci in the callus population. The fine mapping of S1 and S19 loci using CSSLs revealed precise distances of markers from the positions of HS loci exhibiting excessive TRD.

Conclusions

We demonstrated that AC to generate callus populations derived from immature microspores is a useful methodology for genetic study. The callus population facilitated detection of TRD at multiple HS loci and dramatically shortened the process for mapping hybrid sterility genes.
  相似文献   
5.
Here, we aimed to study the slow muscle of the fish Piaractus mesopotamicus submitted to 30 days of fasting (D30) followed by 1 day (D31) or 30 days of refeeding (D60). Histological analysis of fibre diameter was performed in D30 and D60. The gene expression of parvalbumin (pvalb), atrogenes (murf1a, murf1b, mafbx) and anabolic genes (igf‐1, mtor) was analysed using RT‐qPCR in D30, D31 and D60. The proteome was obtained by shotgun proteomics at D30 and D60, and the set of differentially expressed proteins was analysed by bioinformatics. In all experiments, the control was regularly fed fish. The histological analysis showed no changes in muscle fibre diameter. The expression of catabolic and anabolic genes was not changed, except for the downregulation of igf‐1 in D30 and of mafbx in D31. The expression of pvalb was not changed in D30 and D60 but was decreased in D31. The proteomic analysis identified 169 proteins in D30 (24 upregulated and 18 downregulated) and 170 proteins in D60 (17 upregulated and 21 downregulated); many of them were related to energetic metabolism and intracellular Ca2+ homoeostasis. Overall, our results indicate that the slow‐twitch muscle presented few changes upon prolonged fasting and refeeding condition.  相似文献   
6.
In our efforts to find new tyrosinase inhibitory materials, we investigated 44 Indonesian plants belonging to 24 families for tyrosinase inhibitory activity. The extracts of 5 Artocarpus woods showed potent tyrosinase inhibitory activity (over 80% at 100 μg/ml) similar to a positive control, kojic acid. In Artocarpus woods, the extracts of the sapwoods showed stronger inhibitory activity than those of the heartwoods. Chlorophorin was isolated as one of the active compounds in the sapwood of Artocarpus heterophyllus. The content of chlorophorin in sapwood was higher than that in heartwood. Part of this paper was presented at the 53rd (Fukuoka, March 2003) and 54th (Hokkaido, August 2004) Annual Meetings of the Japan Wood Research Society, and the 5th International Wood Science Symposium (Kyoto, September 2004)  相似文献   
7.
This study examined the antibacterial activity of moso bamboo shoot skin (Phyllostachys pubescens). Bamboo shoot skin itself and its dichloromethane extract had antibacterial activity against Staphylococcus aureus. Results suggest the possibility of effective utilization of antibacterial materials from bamboo shoot skins that are mainly discarded at present.  相似文献   
8.
Language acquisition is one of the most fundamental human traits, and it is obviously the brain that undergoes the developmental changes. During the years of language acquisition, the brain not only stores linguistic information but also adapts to the grammatical regularities of language. Recent advances in functional neuroimaging have substantially contributed to systems-level analyses of brain development. In this Viewpoint, I review the current understanding of how the "final state" of language acquisition is represented in the mature brain and summarize new findings on cortical plasticity for second language acquisition, focusing particularly on the function of the grammar center.  相似文献   
9.
In humans, steroid 5α-reductase is involved in the development of benign prostatic hyperplasia (BPH). We tested the steroid 5α-reductase inhibitory activity of the 70% acetone extract of woody plants. The tannin polymer prepared from the 70% acetone extract showed the highest steroid 5α-reductase inhibitory activity. Furthermore, the steroid 5α-reductase inhibitory activity of tannins was not affected by the addition of superoxide dismutase or catalase. It was concluded that the steroid 5α-reductase inhibitory activity of condensed tannin was caused by binding to the steroid 5α-reductase, rather than from the peroxide/superoxide produced by tannins. The tannins, prepared from tree barks, with potential for steroid 5α-reductase inhibitory activity might be advantageous in therapy for steroid 5α-reductase diseases such as BPH or prostate cancer. Part of this report was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, August 2004  相似文献   
10.
Ganoderic acid Df, a new lanostane-type triterpenoid, was isolated from the fruiting body of Ganoderma lucidum. Its structure was characterized as 7β, 11β-dihydroxy-3, 15, 23-trioxo-5α-lanosta-8-en-26-oic acid by 1D- and 2D-NMR spectra. This compound exhibited potent human aldose reductase inhibitory activity, with an IC50 of 22.8 μM in vitro. A carboxyl group of this compound's side chain is essential for eliciting inhibitory activity because its methyl ester is much less active.  相似文献   
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