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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(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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The activities of tobramycin derivatives acetylated and ethylated on the '-N, '-N and 3-N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that '-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 '-N or '-N ethylation protects the drug against inactivation by AAC(') or AAC('), respectively, and '-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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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 DESRA 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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Natural sedimentary clays exhibit ageing effects on their behaviour when subjected to both consolidation and shearing. Attempts to characterising the in-situ 'structure'of soft marine clays have been made in case studies performed in Ariake (Japan) and in Bangkok (Thailand), each showing a typical profile of aged clay-structure with depth reflecting its site-specific geological consolidation history. In each site, profiles of Atterberg limits, natural water content, overconsolidation ratio (OCR), quasi-elastic shear modulus G_max and the undrained shear strength c_u with depth were attained from various laboratory tests, together with the a comparable profile of quasi-elastic shear modulus from insitu seismic survey G_f. Quantitative assessment of the aged clay-structure was made by using two different measures, metastability index MI (G) and the soil constant reflecting structure S (Jamiolkowski et al., 1994). The profiles of MI (G) and the S-value with depth were both determined based on the corresponding G_max behaviour of the reconstituted sample. "Disturbance"of laboratory samples retrieved by using two different samplers (i.., Laval and Japanese thin-walled samplers) with two different sampling techniques (i.., pre-boring and displacement methods) was discussed. A new approach to estimate c_u"in the ground", termed by the authors the MILK (Metastability Index coupled with Laboratory K_o test) method, is proposed. A trial of the MILK-method is demonstrated in soft Bangkok clay, the texture of which is similar to "soft cheese".

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カンキツ主要12種を用いて染色体のクロモマイシン A₃(CMA) 染色を行った．染色体は CMA(+) バンドの有無および位置から 種類に区分できた．すなわち，CMA(+) を A: 両端および動原体近傍に有する，: 一方の端部と動原体近傍に有する，: 両端に有する，D: 一方の端部に有する，: CMA(+) がない，: 動原体近傍に有する，Dst: 付随染色体を有する D 型，である．各種はこれらのうち ～ 種類の染色体を有し，独自の CMA バンドパターンを示した．

C

. medica では + D + ，

C

. limon では + + D + ，

C

. aurantifolia では + D + ，

C

. aurantium では A + + + D + ，

C

. sinensis では + + D + ，

C

. maxima では 3A + 3 + 4D + ，

C

. paradisi では A + 3 + D + ，

C

. ichangensis では + + 12D + ，

C

. latipes では A + + D + 3，

C

. micrantha では + 11D + 4 + Dst，

C

. macroptera では + + 11D + 3 + ，

C

. hystrix では 3 + + D + 3 + + Dst であった．

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Two new partially saturated tricyclic ring systems, , a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (4a and 4) were synthesized. Compounds 4a and 4 were desulfurized to give a pair of isomeric -methylbenzoylcyclohexanes (10a and 10). Deuterated 4a and 4 (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), 4a (trans) and 4 (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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11-Amino-, a, , , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-d) and -oxepines (a-d) were synthesized by the Leuckart reaction of , a, , , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (a, )and -oxepines (a, ) followed by hydrolysis of the reaction products 4a-d and a-d, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and a, cis(a-H, 10a-H)-trans(10a-H, 11-H) and , trans(a-H, 10a-H)-trans(10a-H, 11a-H) and , and trans(a-H, 10a-H)-cis(10a-H, 11-H) d and d, 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 th-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 th-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, .%, ≤ -55dB with a 100MHz input, and +10.3dBm, respectively, all with a ±0.Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a .V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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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–

,500 μm tall). On % 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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わが国における主要中晩生および香酸カンキツ染色体のクロモマイシンA₃ (CMA) 染色を行った. 染色体はCMA(+) バンドの有無および位置から種類に区分できた. すなわち, CMA(+) をA: 両端および動原体近傍に有する, : 一方の端部と動原体近傍に有する, : 両端に有する, D: 一方の端部に有する, : CMA(+) がない, である. 各種はこれらのうち4, 種類の染色体を有し, 独自のCMAバンドパターンを示した. ハッサクではA++D+, ヒュウガナツではA++D+, ‘川野なつだいだい’ではA++D+, ‘宮内伊予柑’ではA+++D+, タンカン‘垂水号’ではA+++D+, カボスでは3++D+, スダチでは++D+およびユズ‘山根’では++11D+4であった. 以上の結果, 本研究においても近縁の種間では似通ったCMAバンドパターンが観察された.

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-Benzyl-4-chloro--mercapto-3 (H)-pyridazinone () was heated in ethanol under reflux for 10 hours to form concurrently , -dibenzyldipyridazo [4, - : 4', '-]-, 4-dithiin-, (H, H)-dione (Ia) (57% in yield) and , -dibenzyldipyridazo [4, - : 4', '-]-, 4-dithiin-, (H, 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 [4, - : 4', '-]-, 4-dithiin-, (H, H)-dione and the -, (H, H)-dione were observed in, not only heating 4-chloro--mercapto-3 (H)-pyridazinones (-3) in polar solvent, but warming 4-mercapto--chloro-3 (H)-pyridazinones (4-) 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 -phenylimino--benzylpyridazo [4, -d]-, 3-dithiol-4 (H)-one (IVa) (14% in yield) along with the major products, (Ia) and (IIa), was furnished by warming 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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All the birds examined were also associated with bone dysplasia (art alczaormal develop-ment of bone tissue) in the diaphyseal cortex of the leg bones, especially of bones affectedwith dyschondroplasia. This result is very significant in order to clarifyz tlais disease entity.1970:J14, k - } ) , M77 ) i? ht /, ( K ) ( # L", MB @ () t, If!TB& U ", Jff Dyschondroplasia (*t%fi!dW) ().g:#[!:.fLlt! K?3o, [: ()M;tC, rff.?U/:cD, bb=lC#li*H(DX15RI!!D& t, r, ccl)Efffflr.#.??t"ut:.?T<3..?l??/?t:>"A??!? > >?TMOll?, lI]%G (-srRM) -ts;;.*BI) *M[t fL 54 t:.;*.{*I[l?(), t@Yllll*fJ?H@() %?Jfipj@ (Dyschondroplasia) p, }, (, lTi{-X, WIKIM itt{= t D"tl%tff{tO 1111IH(-UP!z U-ii) >ES- -)%Wi*fd?J*[lEj: >11"iifI".*"H*Tl*&Z") #)/?-"k l - vich ) J&it(Vh3iO"= >If-ffi"!lYl*I4")Ji/l![40111!>D*!)<Y14M)?A"!>CL(Il], k.ClT"ltTt*flB? & $4U [-" U" L % w, Zl*.IlBl tIJ, FA(y L-x") LVfAK t: >3llltPJ4IiI " } ) t- ! Al j: >kP11liR, &ffl(NWi Z 3lk(#L" Ct ?!4M"- fL#, -()%.IWMd.XI*IEPW(tit fflR)

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A biosynthetic pathway for (

)-methyl cinnamate formation was evaluated in Tricholoma matsutake by tracer experiments using

13C

- and

2H

-labeled precursors. One hundred percent selective

13C

incorporation was observed when L-[

1

,

2

,3,4,

5

,

6

,

7

,

8

,

9

-

13C₉

, ^15/N]phenylalanine was converted to (

E

)-[

1

,

2

,3,4,

5

,

6

,

7

,

8

,

9

-

13C₉

]cinnamate and (

E

)-[

1

,

2

,3,4,

5

,

6

,

7

,

8

,

9

-

13C₉

]methyl cinnamate. Similarly, 100% selective

13C

incorporation was observed when (

E

)-[

1

,

2

,3,4,

5

,

6

,

7

,

8

,

9

-

13C₉

]cinnamate was converted to (

E

)-[

1

,

2

,3,4,

5

,

6

,

7

,

8

,

9

-

13C₉

]methyl cinnamate. In contrast, the

2H

incorporation selectivities were 82.

1

% and 81.4% when L-[

2

,3,4,

5

,

6

,

7

,

7

,

8

-

2H₈

]phenylalanine was converted to (

E

)-[

2

,3,4,

5

,

6

,

7

,

8

-

2H₇

]cinnamate and (

E

)-[

2

,3,4,

5

,

6

,

7

,

8

-

2H₇

]methyl cinnamate, respectively. Thus, T. matsutake synthesizes (

E

)-methyl cinnamate from L-phenylalanine via (

E

)-cinnamate. (

E

)-cinnamate was likely formed through two pathways: one was major and the other was a minor.

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