Chemical properties of ergosta-, , (14), -tetraen-3-one (1) were investigated. Though 1 is rather stable to acids or bases, it reacts easily with two moleculres of oxygen on irradiation with UV light to give , -epidioxy-14α-hydroperoxyergosta-, 7, -trien-3-one (2), which is transformed successively to , 7α;, -diepoxy-14α-hydroperoxyergosta-, -dien-3-one (3) and 14α-hydroperoxy--hydroxyergosta-, 7, -triene-3, -dione () under these reaction conditions.

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In the first part of the present work the interaction of glycophorin with dimyristoylphosphatidylcholine (DMPC) is studied by freeze fracture electron microscopy, densitometry, calorimetry, and 90° static light scattering. An exothermic lipid/protein interaction energy of W_P=190 kJ•mol^-1 was found by application of the well known Van Laar relation for the displacement of the freezing point and the Gibbs-Duhem relationship. Secondly, the effects of Ca²⁺ on the lipid/protein interaction were studied. Following Ca²⁺ addition a remarkable decoupling of the interaction of the glycophorin head group with the bilayer surface was revealed by densitometry and gold-labeling electron microscopy. It is estimated that about 80% of lipid once disturbed by the adsorption of glycophorin head groups is decoupled after addition of Ca²⁺. Thirdly, the selective interaction of glycophorin with binary lipid mixtures was studied, including the mixtures of DMPC with dimyristoylphosphatidylserine (DMPS) and dilauroylphosphatidylcholine (DLPC), and the mixture of dipalmitoylphosphatidylcholine (DPPC) with DLPC.

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Eight new sterols, 5α, -epidioxy-(, 24R)-23-methylergosta-, -dien-3β-ol (1), 3β, 5α, -trihydroxy-(, 24R)-23-methylergosta-7, -dien--one (2), 3β, 5α, -trihydroxy-(24S)-ergost-7-en--one (3), 3β, 5α, , 14α-tetrahydroxy-(, 24R)-ergosta-7, -dien--one (), (, 24R)-ergosta-7, -diene-3β, 5α, , -tetrol (5), 5α, -epidioxy-3β-hydroxy-(, 24R)-ergosta-7, -dien--one (), 5α, -epidioxy-3β-hydroxy-(24S)-ergost-7-en--one (7) and 5α, -epoxy-(, 24R)-ergosta-, -diene-3β, 7β, 14α-triol (), have been isolated from five edible mushrooms, Lentinus edodes, Flammulina velutipes, Hypsizigus marmoreus, Pleurotus ostreatus and Pholiota nameko together with fifteen known ones (-23), of which two (16 and 17) are reported for the first time from a fungal source. The structures of these new compounds were elucidated on the basis of their spectral data.

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Six new sterols, 5α, ;, -diepoxy-(, 24R)-ergost--ene-3β, 7α-diol (1), 5α, ;, -diepoxy-(, 24R)-ergost--ene-3β, 7β-diol (2), 5α, -epoxy-(, 24R)-ergosta-, -diene-3β, 7β-diol (3), (, 24R)-23-methylergosta-7, -diene-3β, 5α, -triol (), (, 24R)-23-methulergosta-7, -diene-3β, 5α, , -tetrol (5) and (24S)-ergost-7-ene-3β, 5α, , -tetrol (), have been isolated from seven mushrooms, Amanita pantherina, Amantia virgineoides, Lactarius piperatus, Lyophyllum shimeji, Tricholoma portentosum, Hypsizigus marmoreus and Lentinula edodes together with eighteen known ones (7-24). The structures of these new compounds were elucidated on the basis of their spectral data.

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We purified a sterol with antitumor activity from the edible mushroom Sarcodon aspratus (BERK.) S. ITO and identified it as 5α,-epidioxy--ergosta-,(11),-trien-3β-ol (,11-dehydroergosterol peroxide ((11)-DHEP)). Purified (11)-DHEP was a more effective inhibitor of HL60 leukemia cell growth and stronger apoptosis-inducer than 5α,-epidioxy--ergosta-,-dien-3β-ol (ergosterol peroxide (EP)) that we had previously identified as an apoptosis inducer. Moreover, (11)-DHEP selectively suppressed the growth of HT29 human colon adenocarcinoma cells but not WI38 normal human fibroblasts. After 5 d incubation of HT29 with 7 μM (11)-DHEP, the number of S phase cells decreased from 23 to 15% of total diploid cells and 17% became hypodiploid. Expression of the cyclin-dependent kinase inhibitor 1A (p21, WAF1, Cip1) (CDKN1A), which has been shown to cause cell cycle arrest and apoptosis in HT29 cells, was induced by (11)-DHEP. These results suggest that (11)-DHEP inhibits HT29 cell growth by inducing CDKN1A expression, thus causing cell cycle arrest and apoptosis.

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This report describes a patient with extramedullary relapse of acute myeloid leukemia (AML) without involving bone marrow. A 57-year-old man was diagnosed as having acute monoblastic leukemia with t(;11)(p;q23) and trisomy . Ten months after achieving complete response (CR) with chemotherapy, masses developed in his left forearm and in the back of his thigh, preceded by enigmatic peripheral neurological symptoms. Aspiration from the forearm showed leukemic relapse, and fluorescence in situ hybridization (FISH) revealed that the majority of the cells had 11q23 anomaly and tetrasomy . Bone marrow or meningeal relapse was not observed. To our knowledge, this is the first case report of clonal evolution associated with the development of myeloid sarcoma as a relapse in AML.

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From the black coral Antipathies dichotoma, a sphingolipid (2S*,3S*,,)-2N-[tetradecanoyl]-(),()-icosadiene-1,3-diol (1) and a steroid ()-methylcholesta-5,-diene-1α,3β,7α-triol (2) were isolated. Other known compounds, 3β,7α-dihydroxy-cholest-5-ene (3), (,24S),5α,-epidioxy-24-methylcholesta-,-dien-3β-ol () and (,24S),5α,-epidioxy-24-methylcholesta-,(11),-trien-3β-ol (5). The structures were established on the basis of NMR spectroscopic analysis and comparison with literature. The antibacterial activity of five compounds was evaluated.

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Repetitive liquefactions in angular and subangular gravels from an alluvial fan, in the case of two earthquakes with accelerations lower than that of a former which had caused liquefaction some months before, are described. The liquefaction took place from the surface, down to a depth of approximately 10 m. Water laden with sediments spouted out for some tens of minutes after the strong motion ceased. Knowledge of the grain size distribution of the sediments inside the body of the alluvial fan roughly defines the areas of the fan prone to future liquefaction. Non-repetitive liquefaction in overconsolidated fine fluvio-lacustrine sand of glacial origin at the unusual depth of 14 m to 16 m is also described. From the observation of sand lifted up for 10 m inside a large diameter well, and of that which spouted out from several microvents, it was estimated that extra-pore pressure was close to lithostatic conditions. Nevertheless, modeling of intrinsic pore pressure buildup on the DESRA2 programme gives lower values than the experimental one. Geotechnical characteristics of the 12 m-thick sandy stratum indicate that the upper part is unusually soft, either due to water circulation or past repetitive liquefactions which prevented reconsolidation. It is suggested that excess pore pressure generated by the earthquake was also due to redistribution of pressure from adjacent sediments.

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Accumulated evidences suggest that soluble oligomers of amyloid β42 and 40 (Aβ42 and 40) would be responsible for the Alzheimer’s disease. We proposed putative toxic dimer and trimer structures of Aβ42 with a turn at positions

and 23 (toxic turn) based on the systematic proline replacement, electron spin resonance, and solid-state NMR. Based on these structures, we synthesized several dimer models of the toxic-conformation-restricted P-Aβ40 using an ʟ,ʟ-2,-diaminopimeric acid (DAP) or an ʟ,ʟ-2,-diaminoazelaic acid linker (DAZ) at position 30 or 38 (Fig. , 1～3). The trimer models of P-Aβ40 using 1,3,5-phenyltris-ʟ-alanine (PtA) as a linker at position 34, 36, or 38 were also synthesized (Fig. , ～). Ion mobility-mass spectrometry suggested that high-molecular weight oligomers (12～24-mer) were formed only in the dimer model with DAP linker at position 38 (3), and this model exhibited potent neurotoxicity against SH-SY5Y cells. Although only the trimer model with PtA at position 38 () existed as high-molecular weight oligomers (～21-mer), its neurotoxicity was far less than that of the corresponding dimer model (3). These data indicate that the -terminal hydrophobic core plays an important role for the formation of high molecular weight oligomers (～20-mer) with neurotoxicity, and such a propeller-type trimer model () could not give oligomers with potent neurotoxicity. Similar results were obtained using the corresponding dimer and trimer models of P-Aβ42 (P-V40DAP-Aβ42 dimer, P-V36PtA-Aβ42 trimer, and P-V40PtA-Aβ42 trimer), suggesting that the results obtained in the Aβ40 dimer and timer models could be extended to the models of more toxic Aβ42.

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急性骨髄性白血病(AML)の寛解導入療法において，海外の基礎および臨床研究では，IDRの有用性が数多く報告され，IDRとシタラビン(Ara-)の組み合わせが治療戦略の主体となっている。われわれは1995年5月から1998年10月までの当科におけるIDRを寛解導入療法に用いた初発AML41例について，その臨床経過，寛解率，再発率，予後について検討した。その成績は当科での92年から95年に行った，寛解導入にDNRを用いたJALSG-AML92登録26例の成績とほぼ同等であった。なお前者では，従来予後良好因子とされているt(;21)(q;q)を有する症例5例が全例再発し，IDRによる寛解導入療法ではこの染色体異常は予後を反映しないことが示唆されたが，CD56陽性など予後不良因子が加味していたことも疑われる。今後長期予後を期待するためには，寛解導入後の地固め療法をより強化することが必要と考えられた。

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Glucosylceramide (G1cβ1-1Cer) was isolated from the spermatozoa of the starfish, Asterias amurensis. The long-chain bases of the glycolipid consisted of dihydroxy (d18:2, d18:3, d19:3, and d:2), and trihydroxy (t:1) types. Long-chain aldehydes derived from them were analyzed mainly by proton nuclear-magnetic resonance to determine the detailed structures. Two of the tri-unsaturated bases were identified as (, , )-2-amino-, , 10-octadecatriene-1, 3-diol (d18:3) and (, , )-2-amino--methyl-, , 10-octa-decatriene-1, 3-diol (d19:3), which is a novel base. Both d:2 and t:1 had a cis double bond at the or 13 position. All fatty acids were 2-hydroxylated (-):Most of themwere saturated and unbranched. About 10% was mono-unsaturated and unbranched (-), while saturated but branched (iso- and anteiso-types) - acids were found as mi-nor components. The main fatty acids, which summed up to more than 93% of the fatty acids in the glucosylceramide, were n-14h: 0, n-15h:0, n-16h : 0, n-17h : 0, n-18h : 0, and n-24h:1.

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Four new sterols, 5α, -epoxy-(, 24R)-ergosta-(14), -diene-3β, 7β-diol (1), (, 24R)-ergosta-, -diene-3β, 5α, , 7α-tetrol (2), (, 24R)-ergosta-7, (11), -triene-3β, 5α, -triol (3) and 3β, 5α, -trihydroxy-(, 24R)-ergost--en-7-one (), have been isolated from the fruit bodies of Grifola frondosa (FR.) S. F. GRAY (Polyporaceae)together with fourteen known ones (5-18), of which two (5 and ) are reported for the first time from a natural source. The structures of these compounds were elucidated on the basis of spectral data.

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