(

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 6'-N, 2'-N and -N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that 2'-N-ethylated and 6'-N-ethylated derivatives have a fairly good activity, and confirmed that the -N position is the most important one for antibiotic activity since -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 6'-N ethylation protects the drug against inactivation by AAC(2') or AAC(6'), respectively, and 2'-N-ethyltobramycin and 6'-N-ethyltobramycin were active against strains containing these modifying enzymes. On the other hand, -N ethylation protects the drug against inactivation by AAC() but -N-ethyl tobramycin does not inhibit strains containing this enzyme.

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A sample of [

3H

] tobrarnycin (5, 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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Six full-length cDNAs encoding pig cytochrome P450 (CYP) enzymes, CYPA, CYP2A19, CYP2B, CYP233v4, CYP249, and CYP2, were isolated and sequenced. The cDNA sequences of pig CYPA, CYP2A19, CYP2B, CYP249, and CYP2 showed high similarity to human (85.4%), CYP2A13 (88.6%), CYP2B6 (.%), (85.%), and (.5%), respectively, and pig cDNA showed high similarity to rat (79.2%). Reverse transcription-polymerase chain reaction (RT-PCR) assays revealed hepatic gene expression of all these pig CYP enzymes: the order of expression was and > > and CYP2A19 > . In the kidney, the gene was expressed at the same level as in the liver, but the , CYP2A19, and genes were expressed at lower levels than in the liver. Little renal gene expression of CYP249 and CYP2 was observed. We revealed for the first time the full-length cDNA sequences encoding pig CYPA and five CYP enzymes belonging to the CYP2 gene family, thus making it possible to examine the gene expression levels of these CYP enzymes in pig tissues by RT-PCR.

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This paper is concerned with dynamics of the standard penetration test (SPT). The usefulness of mounting strain gages at two different stations along a driven rod is described, together with a workable procedure of analysis. The analysis procedure makes use of the traveling time between the two gage points and enables one to identify the particle velocity, the displacement and the stress at any station of the rod, as well as the energy actually transmitted from a hammer to the rod. Particular attention is called for the consequence of inevitable, small errors in strain data upon such identifications. A pertinent procedure of error-correction is proposed and its validity is substantiated against the performance of well instrumented SPTs performed by the authors.

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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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Realization of a -D TV system using the present day HDTV is proposed. This system is based on the stereoscopic principles transmitting the left and right eye view images of the object on multiplexed video lines. In the receiver, the video lines are demultiplexed, the missing lines are interpolated and the stereo pair of images are reconstructed in two picture tubes. By means of a bicircularily polarized viewing system, these stereo pair of images are made to offer a true -D vision. This system takes the advantage of high resolution offered by teh HDTV system and at the same time adds only a minimal complexity to the circuitry of the HDTV transmitter and the receiver for converting the HDTV into -D TV.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MCT-. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MCT- 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-7,-diene-,5α,6β-triol (). induced ALP activities of MCT- cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MCT- cells by , ergosterol (2), ergocalciferol (), cholesta-,5α,6β-triol (4), 7-dehydrocholesterol (5) and cholecalciferol (6) were tested. The enzyme activities of MCT- cells were increased .0-fold by 10 μM and 2.4-fold by 10 μM 4. However, 2, , 5 and 6 did not induce MCT- cell ALP activity at 0.—10 μM. These results suggested that the OH groups at -5 and/or -6 of and 4 played an important role in their differentiation-inducing activities on MCT- cells. Furthermore, suppressed induction of MCT- cell apoptosis by serum starvation.

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Chemical synthesis of (, 24R)- and (, 24S)-, 24-dihydroxy--vitamin has been achieved starting with the commercially available dinorcholenic acid acetate. Synthesis involved introduction of the -hydroxy group by a reduction of the , 2-epoxide generated by epoxidation of the , 4, 6-trien--one. The side chain on the steroid was then constructed by means of a Wittig reaction followed by introduction of the Δ⁷ bond by standard methods and its protection with -phenyl-, 2, 4-triazoline-, 5-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 5, 7-dienes were irradiated and the corresponding vitamin D compounds isolated. Nuclear magnetic resonance was used to identify individual isomers. The (, 24S)-, 24-hydroxyvitamin compound bound equally well to the chick intestinal cytosol receptor as , 25-dihydroxyvitamin , while the 24R-isomer was approximately ten times less active. In vivo, both isomers were less active than , 25-dihydroxyvitamin ; however, the 24S-isomer was considerably more active than the 24R-isomer approaching the activity of , 25-dihydroxyvitamin .

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Six new cembranoids sarcophytol P (), R (4), S (5), K (), F (11), and T (13) were isolated from the soft coral Sarcophyton glaucum. Sarcophytol P () was shown to be the 20-hydroxy derivative of the major component sarcophytol A (), and afforded the cyclization product 6 in CHCl_ at room temperature, in a same way as in . Sarcophytols R (4) and S (5) were correlated to , by conversion of its 7R,R and 7S,S epoxide derivatives. Sarcophytol K() was a 13, 14-dihydroxycembranoid having a ,Z-diene moiety. The absolute configuration of and its Z,- and Z,Z-isomers sarcophytol B (2) and J (10) were determined by circular dichroism study of their bis-p-dimethylaminobenzoate derivatives. Sarcophytols F (11) and T (13) were - and ,Z-isomers of . Compound 11 showed characteristic broadening of the ^H-NMR chemical shifts, due to the restricted conformational interconversion. Using the three cembranoids sarcophytols F (11, ,), N (15, Z,Z) and T (13,,Z), spontaneous autoxidation-cyclization, in CHCl_,was examined, in order to compare the stereochemical course of the reaction with that of (Z,), which affords trans-fused bicyclo[9..0]tetradecene systems. The ,Z-isomer 13 gave the same cyclization product 18, as in the reaction of , even though it is isomeric at -,. The Z,Z isomer 15 gave 19, in consequence of the reversed geometry at - of 15. The ,-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 (14)-epoxide 26 was shown to be the immediate precursor of , and acounted for the inversion of the geometry at - of the cyclization product. Compound 26 is isomeric with the epoxide 17 derived from . 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 , also reacted in CHCl_ giving the bicyclic product 32.

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Glucosylceramide (-Cer) was isolated from the spermatozoa of the starfish, Asterias amurensis. The long-chain bases of the glycolipid consisted of dihydroxy (d18:2, d18:, d19:, and d:2), and trihydroxy (t:) 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-4, , 10-octadecatriene-, -diol (d18:) and (, , )-2-amino-9-methyl-4, , 10-octa-decatriene-, -diol (d19:), which is a novel base. Both d:2 and t: had a cis double bond at the 9 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:.

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Background : Usefulness of endoscopic microwave coagulation therapy (-MCT) was examined in 27 patients with hepatocellular carcinoma (HCC).
Material and Methods : HCC was found in patients with type B liver cirrhosis (LC), 16 patients with type LC, and patients with non B non LC. Median tumor size was 23 mm (solitary lesion , multiple 5). Laparoscopic MCT was performed for S_2-6 lesion and thoracoscopic MCT for lesion under general anesthesia. Linear type ultrasonography was used in every case for monitoring lesion ant therapeutic effect.
Results : Complete tumor necrosis was obtained in 24 cases (%) and local recurrence was found in 5 cases after the observation period of maximum 34 months. Pleural abscess, hemorrhage and hepatic infarction were found in cases without serious outcome.
Conclusions : We conclude that -MCT is quite promising therapy for surface type HCC in term of minimally invasive and curative procedure a time. It is important that sufficient marginal coagulation should be obtained.

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