A sample of [³H] tobrarnycin (, 000 Ci/Mole) has been synthetized and incubated with
the bacterial ribosome and its subunits. The results obtained show that this antibiotic has
two types of binding sites. The primary one is probably responsible for the inhibition of
protein synthesis whereas the secondary one is probably related to the misreading and reading
tiirough of the messenger RNA.

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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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Two new partially saturated tricyclic ring systems, , a, 7, , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (a and ) were synthesized. Compounds a and were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated a and (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), a (trans) and (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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The activities of tobramycin derivatives acetylated and ethylated on the '-N, 2'-N and 3-N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that 2'-N-ethylated and '-N-ethylated derivatives have a fairly good activity, and confirmed that the 3-N position is the most important one for antibiotic activity since 3-N derivatives were less active. The MICs of these derivatives against tobramycin resistant strains, and their inactivation by tobramycin modifying enzymes were examined. These results showed that 2'-N or '-N ethylation protects the drug against inactivation by AAC(2') or AAC('), respectively, and 2'-N-ethyltobramycin and '-N-ethyltobramycin were active against strains containing these modifying enzymes. On the other hand, 3-N ethylation protects the drug against inactivation by AAC(3) but 3-N-ethyl tobramycin does not inhibit strains containing this enzyme.

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(³H) Tobramycin was used as a probe to determine the relationship between the structure of aminoglycoside antibiotics and their ability to remove this drug from its higher affinity binding site on the ribosome. The dissacharide moieties (neamine, tobramine, gentamine) appeared to have a common binding site, whereas the kanosamine, garosamine and ribose moieties determined the specificity of this binding. Amikacin and butikacin behaved in an anomalous manner in spite of their close structural relationship to tobramycin.

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11-Amino-, a, 7, , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-d) and -oxepines (7a-d) were synthesized by the Leuckart reaction of , a, 7, , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (2a, ) followed by hydrolysis of the reaction products a-d and a-d, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and 7a, cis(a-H, 10a-H)-trans(10a-H, 11-H) and 7, trans(a-H, 10a-H)-trans(10a-H, 11a-H) and 7, and trans(a-H, 10a-H)-cis(10a-H, 11-H) d and 7d, were isolated and their configurations and conformations were elucidated by chemical methods together with ¹H-nuclear magnetic resonance spectroscopic and X-ray crystallographic analyses.

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS 7th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a 7th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -3dB frequency bandwidth, group delay ripple, 3rd-order distortion, and 3rd-order input intercept point (IIP3) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.3dBm, respectively, all with a ±0.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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This study was performed to clarify which factors affected damage to tame-ike (small embankment dams for irrigation) in Hokudan Town as a result of the January 17, 1995 Hyogoken-Nambu earthquake. Factors were assumed to be : Location (.g., Distance to Epicenter, etc.), Structure (.g., Angle to Nearest Fault, Embankment Volume, etc.), Soil Properties of Embankment, Geology of Dam Site and History (Era of Construction, Repaired, etc.). Multivariate statistical analyses were performed for documentary data (damaged : 181, undamaged : 328). Ordinary statistical analyses were conducted for the data investigated in situ for soil properties of the embankment. The results show that the factors causing damage to dam are : (1) Nearest Fault (Nojima, Mizukoshi and D2), (2) Distance to Nearest Fault (less than 500 m), (3) Distance to Epicenter (approximately to 14 km, which almost agrees with the location of seismic intensity 7 JMA), () Elevation of Dam Site (higher than 100 m), () Embankment Volume (the greater the volume the more damage was caused), () Direction of Dam Axis (normal or diagonal to the epicenter or to nearest the fault), (7) Plan View of Dam Axis (3 or axes), () Surface Geology of Dam Site (non-cohesive soil type ground), () Era of Construction (prior to 1891) and (10) Soil Properties of Embankment (sand, not silty sand or gravel, penetration resistance that is 10% smaller than the undamaged dams).

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Nine isoquinoline alkaloids belonging to the protoberberine, proaporphine and bisbenzyl-isoquinoline series were isolated from Caryomene olivascens (Menispermaceae). Four compounds are new : (-)-2-norlimacine (), (-)-caryolivine (), (+)-1, 2-dehydro-2-norlimacusine () and N-formylstepharine (3). The last one is the first N-formyl derivative to be reported in the proaporphine group. Its biogenetic origin is discussed. Structures were established on the basis of 360 MHz (FT) nuclear magnetic resonance measurements and also by chemical correlation in the case of 3.

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Two new polyacetylene compounds (, , 12)-1-acetoxy-3-isovaleryloxytetradeca-, , 12-trien-, 10-diyn-14-ol (), and (, , 12)-1-acetoxy-3-(2-methylbutyryloxy)tetradeca-, , 12-trien-, 10-diyn-14-ol () have been isolated along with (, , 12)-1-acetoxy-3-senecioyloxytetradeca-, , 12-trien-, 10-diyn-14-ol (A) from Atractylodes Rhizome (Karabyakujutu). The structures of these compounds were determined on the basis of their spectral data.

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We compared three groups of pregnant women: placebo with normotensive women, group A which included preeclamptics, and group which comprised preeclamptics who were supplemented their diets with vitamins and . MDA increased from . ± 2. (placebo) to .48 ± 1.2 (A) and .02 ± 1. nmol/gHb (). NO concentrations were enhanced from 19.3 ± .2 (P) to 23. ± . (A) and 24.1 ± . μmol/L (). GSH contents were decreased from 10.42 ± 2.81 (P) to .02 ± 2.92 (A) and .39 ± 1.02 μmol/g Hb (), whereas GSSG concentrations increased from 0.98 ± 0.28 (P) to 1.24 ± 0.29 (A) and 1.08 ± 0.12 μmol/g Hb (). SOD activity decreased 23% in A and 14% in ; GRx decreased 27% in A and .% in ; GPx decreased 12% in A and .% in . Catalase activity, however, increased 27% in A and 29% in as compared to control. Thus, we conclude that the use of vitamins and should be considered for the control of certain important biochemical indices during the development of preeclampsia; however, further studies are needed to develop methods for the prevention of preeclampsia in women at high risk.

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A methanol extract of the flowers of Mammea siamensis (Calophyllaceae) was found to inhibit enzymatic activity against aromatase (IC₅₀=16. µg/mL). From the extract, two new geranylated coumarins, mammeasins (1) and D (2), were isolated together with seven coumarins: -hydroxy--methyl-7-(3,7-dimethyl-octa-2,-dienyl)--(2-methyl-1-oxobutyl)-,-dihydropyrano[,3,2-de]chromen-2-one (), -hydroxy--methyl-7-(3,7-dimethyl-octa-2,-dienyl)--(3-methyl-1-oxobutyl)-,-dihydropyrano[,3,2-de]chromen-2-one (10), mammeas A/ (14), A/AB (15), A/ cyclo D (18), /BA (23), and / cyclo D (25). The structures of 1 and 2 were elucidated on the basis of spectroscopic evidence. Among the isolates including 17 previously reported coumarins, 1 (IC₅₀=2.7 µM), 2 (3. µM), and mammea /AB cyclo D (21, 3.1 µM) showed relatively strong inhibitory activities comparable to the activity of the synthetic nonsteroidal aromatase inhibitor aminoglutethimide (2.0 µM).

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2-Benzyl--chloro--mercapto-3 (2H)-pyridazinone (1) was heated in ethanol under reflux for 10 hours to form concurrently 2, 7-dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, (2H, 7H)-dione (Ia) (57% in yield) and 2, -dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, (2H, H)-dione (IIa) (14% in yield). Assignment of the two products to the corresponding structures is established by their physico-chemical constants and chemical behaviors. The concurrent formation of the dipyridazo [, - : ', '-]-1, -dithiin-1, (2H, 7H)-dione and the -1, (2H, H)-dione were observed in, not only heating -chloro--mercapto-3 (2H)-pyridazinones (1-3) in polar solvent, but warming -mercapto--chloro-3 (2H)-pyridazinones (-) in the presence of potassium carbonate in DMF. For the interpretation of the reaction, keto-thioketo carbenes as active intermediate species and a reversible interconversion among them are suggested on the basis of the fact that there was nonexistence of an equilibrium between the two compounds, such as Ia and IIa, under the reaction condition and a trapping keto-thioketo carbene species as 2-phenylimino--benzylpyridazo [, -d]-1, 3-dithiol- (H)-one (IVa) (14% in yield) along with the major products, (Ia) and (IIa), was furnished by warming 1 with phenylisothiocyanate in the presence of triethylamine in dry benzene. On the contrary, participation of a reversible interconversion between Ia and IIa, to a considerable extent, with the concurrent formation of them in the case of benzylation of either Ib or IIb, by warming with benzylchloride in the presence of potassium carbonate in DMF at 80°, might not be neglected, because an attempted approach to an equilibrium between Ia and IIa in a similar reaction condition except the use of benzylchloride realized, whereas non-existence of an equilibrium between Ib and IIb in the similar reaction condition was observed.

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