(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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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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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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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 . ± . (placebo) to .48 ± 1. (A) and .02 ± 1. nmol/gHb (). NO concentrations were enhanced from 19.3 ± . (P) to 23. ± . (A) and 24.1 ± . μmol/L (). GSH contents were decreased from 10.42 ± .81 (P) to .02 ± . (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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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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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 D), () 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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The syntheses of (S)-13-hydroxy-(, , )-tetradecatrienoic acid (1) and (, , Z-tetradecatrienoic acid () were carried out by using the Wittig reaction as the key step. The asymmetric center at -13 and the double bond between - and - for natural compound 1 were reconfirmed as being of (S) configuration and , respectively. The relationship between the structure of the unsaturated hydroxy fatty acids and their inhibitory effect on the growth of lettuce was investigated.

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Six new cembranoids sarcophytol P (3), R (), S (), K (), (11), and T (13) were isolated from the soft coral Sarcophyton glaucum. Sarcophytol P (3) was shown to be the 20-hydroxy derivative of the major component sarcophytol A (1), and afforded the cyclization product in CHCl_3 at room temperature, in a same way as in 1. Sarcophytols R () and S () were correlated to 1, by conversion of its 7R,R and 7S,S epoxide derivatives. Sarcophytol K() was a 13, 14-dihydroxycembranoid having a 1,3Z-diene moiety. The absolute configuration of and its 1Z,3- and 1Z,3Z-isomers sarcophytol () and J (10) were determined by circular dichroism study of their bis-p-dimethylaminobenzoate derivatives. Sarcophytols (11) and T (13) were 1- and 1,3Z-isomers of 1. Compound 11 showed characteristic broadening of the ^1H-NMR chemical shifts, due to the restricted conformational interconversion. Using the three cembranoids sarcophytols (11, 1,3), N (15, 1Z,3Z) and T (13,1,3Z), spontaneous autoxidation-cyclization, in CHCl_3,was examined, in order to compare the stereochemical course of the reaction with that of 1 (1Z,3), which affords trans-fused bicyclo[.3.0]tetradecene systems. The 1,3Z-isomer 13 gave the same cyclization product 18, as in the reaction of 1, even though it is isomeric at -1,3. The 1Z,3Z isomer 15 gave 19, in consequence of the reversed geometry at -3 of 15. The 1,3-isomer (11) gave the bicyclic product , having an antipodal fusion as compared with 19. This was confirmed by PCC oxidation of 19 and , giving enantiomeric ketones 23 and 24 respectively. The 1(14)-epoxide 26 was shown to be the immediate precursor of , and acounted for the inversion of the geometry at -1 of the cyclization product. Compound 26 is isomeric with the epoxide 17 derived from 1. The epoxide 17 is the postulated precursor in the conversion of 13 to 18. It is noteworthy that the mode of antipodal fusion of the cyclopentane rings, in 18 and , was controlled by the chirality of the epoxy rings. The -14 hydroxyl group participates in the transannular cyclization, but was found not to be the requisite functional group for the reaction. Similar treatment of cembrene (30), the parent hydrocarbon of 1, also reacted in CHCl_3 giving the bicyclic product 32.

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-Benzyl--chloro--mercapto-3 (H)-pyridazinone (1) was heated in ethanol under reflux for 10 hours to form concurrently , 7-dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, (H, 7H)-dione (Ia) (57% in yield) and , -dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, (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 [, - : ', '-]-1, -dithiin-1, (H, 7H)-dione and the -1, (H, H)-dione were observed in, not only heating -chloro--mercapto-3 (H)-pyridazinones (1-3) in polar solvent, but warming -mercapto--chloro-3 (H)-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 -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 °, 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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Two new polyacetylene compounds (, , 12)-1-acetoxy-3-isovaleryloxytetradeca-, , 12-trien-, 10-diyn-14-ol (), and (, , 12)-1-acetoxy-3-(-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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This study aimed to determine the prevalence of fecal carriage of extended spectrum β-lactamase (ESBL) and/or plasmidic AmpC β-lactamase (pAmpC) producing Escherichia coli among dogs (n=428) in Turkey. Polymerase chain reaction (PCR) and sequencing were used to characterize genes encoding β-lactamase and plasmid mediated quinolone resistance (PMQR). Antimicrobial susceptibility testing and PCRs for virulence genes and phylogenetic groups were also performed. Cefotaxime resistant

. coli isolates were detected in 95 (.%) of the swab samples. Sequencing analysis results showed occurrence of various β-lactamase genes: bla_CTX-M-15 (62), blaTEM-

1b

(42), blaCMY-

2

(

22

), bla_CTX-M-3 (16), bla_CTX-M-1 (15), bla_OXA-1 (

9

) and bla_SHV-12 (3) alone or in combination. The most frequently encountered phylogenetic group was group A₁ (35.

8

%), followed by group

D₂

(

22

.1%),

B

1 (15.

8

%), D₁ (

9

.

5

%), A₀ (7.

4

%),

B2₂

(

5

.3%) and

B2₃

(

4

.

2

%), respectively. PMQR genes, aac(

6

’)-Ib-cr, qnrS1 and qnrB10 were detected in 25.3, 10.

5

and 1.1% of the isolates, respectively. While all isolates were susceptible to imipenem and amikacin, resistance rates to non-β-lactam antibiotics ranged from 20.0% for tobramycin to 56.

8

% for tetracycline. The virulence genes were only detected in 34 (36.

2

%) of the isolates and this isolates carried single or various combination of virulence genes of iucD, papC, papE,

f17a

-A and eaeA. Four isolates were identified as human virulent pandemic CTX-M-15 producing

E

. coli clone O25

b

:ST131/

B

2

. To the best of our knowledge, this is the first study to show fecal carriage of ESBL/pAmpC type β-lactamase producing

E

. coli isolates among dogs in Turkey.

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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 7 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 1 + 1 + D + ，

C

. aurantifolia では + D + 7，

C

. aurantium では 1A + 1 + 1 + 7D + ，

C

. sinensis では + + 7D + 7，

C

. maxima では 3A + 3 + D + ，

C

. paradisi では A + 3 + D + 7，

C

. ichangensis では + + 12D + ，

C

. latipes では A + + D + 3，

C

. micrantha では 1 + 11D + + Dst，

C

. macroptera では + 1 + 11D + 3 + 1，

C

. hystrix では 3 + 1 + D + 3 + + 1Dst であった．

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New-type inducers of differentiation of human promyelocytic leukemia cells HL-60, i.

e

., - (, , 7, -tetrahydro-, , , -tetramethyl--naphthalenylcarbamoyl) benzoic acid (Am ) and () -- [3- (3, -di-tert-butylphenyl) -3-oxo-l-propenyl] benzoic acid (Ch 55), suppress -myc expression as all-trans-retinoic acid (RA) does. The decreased level of -myc expression was detected within -14 h after the start of treatment, and preceded morphological differentiation and functional differentiation measured in terms of nitroblue tetrazolium (NBT) reduction. Treatment of HL-60 cells with 0.1 μm Am , Ch 55 or RA for 96 h caused more than 90% suppression of -myc expression and around 10-fold increase in the percentage of NBT-positive cells.

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The Gujarat earthquake in India occurred in January, 2001, and caused significant damage in the province of Gujarat. The Japanese Geotechnical Society sent a small reconnaissance team to the damaged region after the quake. The present text presents the report from this activity. The major attention of the team was focused on geotechnical aspects of the damage which were related to earthfill dams and harbor land fills. It was found that a significant portion of damage was concentrated in fills resting on soft natural soils. Swedish weight soundings which were conducted at two places demonstrated the existence of such a soft subsoil. From this, it was concluded that amplification of earthquake shaking as well as the permanent deformation in the soft foundation soil induced such kinds of damage as subsidence, cracking, and lateral spreading in overlying artificial fills. For the better seismic resistance of those affected fills during future earthquakes, the improvement of soft subsoil seems essential.

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