We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-1. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-,-diene-3β,,6β-triol (1). 1 induced ALP activities of MC3T3-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3-1 cells by 1, ergosterol (2), ergocalciferol (3), cholesta-3β,,6β-triol (4), -dehydrocholesterol () and cholecalciferol (6) were tested. The enzyme activities of MC3T3-1 cells were increased 3.0-fold by 10 μM 1 and 2.4-fold by 10 μM 4. However, 2, 3, and 6 did not induce MC3T3-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C- and/or C-6 of 1 and 4 played an important role in their differentiation-inducing activities on MC3T3-1 cells. Furthermore, 1 suppressed induction of MC3T3-1 cell apoptosis by serum starvation.

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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, , -epidioxy-(, 24R)-23-methylergosta-6, -dien-3β-ol (1), 3β, , -trihydroxy-(, 24R)-23-methylergosta-, -dien-6-one (2), 3β, , -trihydroxy-(24S)-ergost--en-6-one (3), 3β, , , 14α-tetrahydroxy-(, 24R)-ergosta-, -dien-6-one (4), (, 24R)-ergosta-, -diene-3β, , 6α, -tetrol (), , -epidioxy-3β-hydroxy-(, 24R)-ergosta-, -dien-6-one (6), , -epidioxy-3β-hydroxy-(24S)-ergost--en-6-one () and , 6α-epoxy-(, 24R)-ergosta-, -diene-3β, , 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, , 6α;, -diepoxy-(, 24R)-ergost--ene-3β, -diol (1), , 6α;, -diepoxy-(, 24R)-ergost--ene-3β, -diol (2), , 6α-epoxy-(, 24R)-ergosta-, -diene-3β, -diol (3), (, 24R)-23-methylergosta-, -diene-3β, , 6β-triol (4), (, 24R)-23-methulergosta-, -diene-3β, , 6β, -tetrol () and (24S)-ergost--ene-3β, , 6β, -tetrol (6), 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 (-24). The structures of these new compounds were elucidated on the basis of their spectral data.

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From the black coral Antipathies dichotoma, a sphingolipid (2S*,3S*,,)-2N-[tetradecanoyl]-4(),()-icosadiene-1,3-diol (1) and a steroid ()-methylcholesta-,-diene-1α,3β,-triol (2) were isolated. Other known compounds, 3β,-dihydroxy-cholest--ene (3), (,24S),,-epidioxy-24-methylcholesta-6,-dien-3β-ol (4) and (,24S),,-epidioxy-24-methylcholesta-6,(11),-trien-3β-ol (). 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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The mechanism of wave-induced instability in a permeable seabed have been studied for more than two decades. The distinction between shear failure and liquefaction, however, has not been clearly defined. This paper presents a fundamental study on the differences in two failure modes for a fully saturated seabed of both finite and infinite thickness. The wave-induced effective stresses and pore pressure, obtained from an analytical solution of Biot's pore-elastic consolidation theory, were employed to examine the failure modes under a two-dimensional plane strain condition. A case study is presented to examine the failure modes with respect to several parameters, such as excess pore pressure, seepage flow, seepage force, failure areas and stress path in the seabed. The conclusions obtained from this study were as follows ; (1) the thickness of a permeable seabed affects the pore pressure and effective stress response to ocean waves and the failure mode of the seabed, (2) either a liquefaction or shear failure, or both, occur in the seabed, even in the saturated seabed, (3) the Mohr-Coulomb's failure criterion, when combined with elastic stresses, can not be employed to estimate the liquefaction failure in the seabed, (4) the liquefaction can be evaluated by a criterion in terms of the excess pore pressure, () The liquefied zone in the seabed is significantly different from the shear failure zone. The shape beneath the seabed surface for the former is almost identical to the contour where the upward seepage flow is concentrated.

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The behavior of the soft clay grounds subjected to repeated loading is different from that subjected to sustained loading. The difference in settlement between these two loading patterns should be due to secondary compression over a long period of time. Consequently, soft clay grounds subjected to repeated loading tend to be more compressible than those subjected to sustained loading. Therefore, it is necessary for engineers to predict post-construction settlements under repeated loading. In this respect, the preloading is considered to be promising as a countermeasure to reduce the settlement of clay under repeated loading as well as under sustained loading. The effect of preloading on post-construction consolidation settlement of soft clay subjected to repeated loading after removal of a part of preload is investigated in the present paper. It has become clear that the settlement of a clay sample after preconsolidation is mainly affected by the amount of preload, the degree of consolidation due to the preload, the amount of permanent load and the amount of repeated load after removal of preload. The calculated settlement versus time relations using a method to estimate the amount of consolidation settlement of soft clay grounds subjected to repeated loading after removal of preloading were compared with the observed degree of consolidation as parameters of the intensities of preload and repeated load.

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Four new sterols, , 6α-epoxy-(, 24R)-ergosta-(14), -diene-3β, -diol (1), (, 24R)-ergosta-, -diene-3β, , 6β, -tetrol (2), (, 24R)-ergosta-, (11), -triene-3β, , 6β-triol (3) and 3β, , 6β-trihydroxy-(, 24R)-ergost--en--one (4), have been isolated from the fruit bodies of Grifola frondosa (FR.) S. F. GRAY (Polyporaceae)together with fourteen known ones (-18), of which two ( and 6) 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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Callipeltin A (1) is a cyclodepsipeptide from water sponge collected at New Caledonia. This compound shows anti-HIV and cytotoxic activities against KB and P388 cells and contains three new amino acid residues. β-methoxytyrosine (β-MeOTyr) (4), (2R,3R,4S)-4-amino--guanidino-2,-3-dihydroxyheptanoic acid (AGDHE) (), (3S,4R)-3,4-dimethyl-L-glutamine (diMeGln) (6). In addition, two new truncated open-chain derivatives of Callipeltin A (1), named Callipeltin D (2) and (3) were isolated. The unique structure and intriguing biological activities of this compound led us to explore total synthesis of Callipeltin A (1) and to elucidate stereochemistry of β-MeOTyr (4). We started to synthesize Callipeltin (3) which contains β-MeOTyr (4). In order to synthesize four stereoisomer of β-MeOTyr (4), we attempted Evans anti or syn-Aldol reaction as a key step. Evans direct anti-aldol reaction with chiral benzyloxazolidinones () and p-hydroxy benzaldehyde () promoted by catalytic amounts of MgCl_2 in the presence of triethylamine and chlorotrimethylsilane. This proceder provide 3:1 diastereoselelctivity and 70% yield of isolated anti-aldol product (10). And Enolizalion of isocyanate oxazolidinone (13) with di-n-butylboryl trifrate and diisopropylethylamine followed by treatment with aldehyde afford syn-aldol product 14 affording 88% yield and 1: anti: sin diastereomeric ratio. On the other hand, we tried Sharpless Asymmetric dihydroxylation (AD) and Aminohydroxylation () to give all four stereoisomers of β-MeOTyr. Treatment of olefin (18) with AD-mix α provided diol (19) and the α position alcohol of 19 was converted to sulfone regioselectively followed by azidation and treatment of 20 with PPh_3 to afford aziridine (21). Addition of aziridine (21) and BF_3・Et_2O in methanol produced α-amino β-methoxy adduct (). reaction protocol with t-butylcarbamate was successfully applied to afford desired in single step. Now we construct Callipeltin to determine absolute stereochemistry of β-MeOTyr (4). In addition, we report the synthesis of diMeGln (6) and (2R,3R,4S)-3-hydroxy-2-4-6-trimethyl hepanoic acid ().

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Chemical synthesis of (, 24R)- and (, 24S)-1, 24-dihydroxy--vitamin D₃ has been achieved starting with the commercially available dinorcholenic acid acetate. Synthesis involved introduction of the 1-hydroxy group by a reduction of the 1, 2-epoxide generated by epoxidation of the 1, 4, 6-trien-3-one. The side chain on the steroid was then constructed by means of a Wittig reaction followed by introduction of the bond by standard methods and its protection with 1-phenyl-1, 2, 4-triazoline-3, -dione. Subsequent reduction of the hydroxy groups in the steroid side chain followed by reduction of the Diels-Alder addition products yielded the both 24-isomers. The , -dienes were irradiated and the corresponding vitamin D compounds isolated. Nuclear magnetic resonance was used to identify individual isomers. The (, 24S)-1, 24-hydroxyvitamin D₃ compound bound equally well to the chick intestinal cytosol receptor as 1, 25-dihydroxyvitamin D₃, while the 24R-isomer was approximately ten times less active. In vivo, both isomers were less active than 1, 25-dihydroxyvitamin D₃ ; however, the 24S-isomer was considerably more active than the 24R-isomer approaching the activity of 1, 25-dihydroxyvitamin D₃.

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The ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–1,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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