Two hundred and eighty-seven drug-resistant strains of Escherichia coli were isolated from 150 ground meat samples of chicken purchased at markets in 1978, and 210 R plasmids were demonstrated in those strains.
The most frequent resistance pattern (%) included SA or TC resistance. The pattern associated with SM resistance was secondly frequent and the frequency of CM resistance was as low as 20%. In relation to TC, CM, SM, and SA, the isolation frequency was the highest with strains triple resistant to any combination of three of four drugs. Among the resistant

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coli strains, R plasmids with single resistance to each of four drugs and those accompanying KM or APC resistance were most frequently demonstrated.
The use of antibiotics has brought many advantages to the livestock industry. The drugs not only cure the animals of bacterial infections but also accelerate growth and the increase in the body size. However, long-term administration of antibiotics has brought an increase in the number of drug-resistant organisms, especially those with conjugally transferable resistance. This paper deals with the studies on the distribution of drug resistance plasmids among

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. coli strains isolated from chickens purchased at commercial markets.
We isolated 287

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. coli strains resistant to any one or any combination of the drugs tested, i.., TC, CM, SM, SA, KM and APC. Drug-resistant

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. coli strains were isolated from all chicken materials tested. SA-and TC-resistant strains were isolated most frequently (.% and .5%, respectively), followed by SM- (68.%) and KM-resistant ones (41.%) . The isolation frequencies of CM- and APC-resistant strains were very low, being .0% and .3%, respectively.

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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-7-guanidino-2,-3-dihydroxyheptanoic acid (AGDHE) (5), (3S,4R)-3,4-dimethyl-L-glutamine (diMeGln) (). 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 % yield and 1:5 anti: sin diastereomeric ratio. On the other hand, we tried Sharpless Asymmetric dihydroxylation (AD) and Aminohydroxylation (AA) 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 _3・Et_2O in methanol produced α-amino β-methoxy adduct (). AA 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 () and (2R,3R,4S)-3-hydroxy-2-4--trimethyl hepanoic acid (7).

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A total of 176

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. coli isolates were retrieved from 203 diarrheic fecal samples collected from Korean cattle on 117 different farms. The most frequently observed resistance in

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. coli isolates was to tetracycline (.%), followed by streptomycin (80.7%) and ampicillin (64.%). Resistance to cefazolin, cefoperazone, cefepime and amikacin was very low. Of the 176

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. coli strains, forty (.7%) isolates from 30 farms showed resistance to fluoroquinolones (FQ). All the FQ-resistant strains possessed double mutations at codons 83 and in the gyrA gene, and a single mutation mostly at codon 80 in the parC gene, except in one isolate. The pulsed-field gel electrophoresis profiles of the FQ-resistant

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. coli isolates were heterogeneous, but two or three isolates that showed an identical pattern originated from the same or different farms. This study demonstrates that FQ resistance is frequently observed in

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. coli from diarrheic cattle and that mutations in the quinolone resistance-determining region are the same as those seen in

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. coli originating from other animal species and humans. The FQ resistance in diarrheic cattle might have been mostly acquired independently, although the possibility of transmission of FQ-resistant

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. coli within a farm or between farms is plausible.

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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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We purified a sterol with antitumor activity from the edible mushroom Sarcodon aspratus (BERK.) S. ITO and identified it as 5α,-epidioxy--ergosta-,(11),-trien-3β-ol (,11-dehydroergosterol peroxide ((11)-DHEP)). Purified (11)-DHEP was a more effective inhibitor of HL60 leukemia cell growth and stronger apoptosis-inducer than 5α,-epidioxy--ergosta-,-dien-3β-ol (ergosterol peroxide (EP)) that we had previously identified as an apoptosis inducer. Moreover, (11)-DHEP selectively suppressed the growth of HT29 human colon adenocarcinoma cells but not WI38 normal human fibroblasts. After 5 d incubation of HT29 with 7 μM (11)-DHEP, the number of S phase cells decreased from 23 to 15% of total diploid cells and 17% became hypodiploid. Expression of the cyclin-dependent kinase inhibitor 1A (p21, WAF1, Cip1) (CDKN1A), which has been shown to cause cell cycle arrest and apoptosis in HT29 cells, was induced by (11)-DHEP. These results suggest that (11)-DHEP inhibits HT29 cell growth by inducing CDKN1A expression, thus causing cell cycle arrest and apoptosis.

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ドコサヘキサエン酸エチル (-DHA) の大量精製方法の確立を目的とし, 固定化Rhizomucor mieheiリパーゼでマグロ油由来のエチルエステル (-DHA 55; -DHA含量, 55mol%) をラウリルアルコール (LauOH) でアルコリシスした。固定化リパーゼを充填したカラム (.0g; ×63mm) に-DHA/LauOH (1 : 7, mol/mol) の混液を30℃, 10mL/hの流速で負荷した。その結果, エステル交換率は58%に達し, エチルエステル画分の-DHA含量はmol%まで上昇した。この固定化酵素リアクターを150日間連続運転すると, エステル交換率は48%まで低下したものの, -DHA含量はほとんど低下せず85mol%まで上昇していた。カラムから溶出した反応液中のエチルエステルは薄膜蒸留により収率よく回収できたが (82%), この画分には2.4wt%のLauOHと.3wt%のラウリルエステルが混在していた。このうち, ラウリルエステルは尿素包括により完全除去することができた。一連の精製操作により, -DHA55に含まれていた-DHAの52%が回収でき, -DHA含量をwt%まで高めることができた。

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Chemical properties of ergosta-4, , (14), -tetraen-3-one (1) were investigated. Though 1 is rather stable to acids or bases, it reacts easily with two moleculres of oxygen on irradiation with UV light to give , -epidioxy-14α-hydroperoxyergosta-4, 7, -trien-3-one (2), which is transformed successively to , 7α;, -diepoxy-14α-hydroperoxyergosta-4, -dien-3-one (3) and 14α-hydroperoxy--hydroxyergosta-4, 7, -triene-3, -dione (4) under these reaction conditions.

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Eight new sterols, 5α, -epidioxy-(, 24R)-23-methylergosta-, -dien-3β-ol (1), 3β, 5α, -trihydroxy-(, 24R)-23-methylergosta-7, -dien--one (2), 3β, 5α, -trihydroxy-(24S)-ergost-7-en--one (3), 3β, 5α, , 14α-tetrahydroxy-(, 24R)-ergosta-7, -dien--one (4), (, 24R)-ergosta-7, -diene-3β, 5α, , -tetrol (5), 5α, -epidioxy-3β-hydroxy-(, 24R)-ergosta-7, -dien--one (), 5α, -epidioxy-3β-hydroxy-(24S)-ergost-7-en--one (7) and 5α, -epoxy-(, 24R)-ergosta-, -diene-3β, 7β, 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, 5α, ;, -diepoxy-(, 24R)-ergost--ene-3β, 7α-diol (1), 5α, ;, -diepoxy-(, 24R)-ergost--ene-3β, 7β-diol (2), 5α, -epoxy-(, 24R)-ergosta-, -diene-3β, 7β-diol (3), (, 24R)-23-methylergosta-7, -diene-3β, 5α, -triol (4), (, 24R)-23-methulergosta-7, -diene-3β, 5α, , -tetrol (5) and (24S)-ergost-7-ene-3β, 5α, , -tetrol (), 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 (7-24). The structures of these new compounds were elucidated on the basis of their spectral data.

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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-7,-diene-3β,5α,-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,5α,-triol (4), 7-dehydrocholesterol (5) and cholecalciferol () 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, 5 and did not induce MC3T3-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C-5 and/or C- 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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From the black coral Antipathies dichotoma, a sphingolipid (2S*,3S*,,)-2N-[tetradecanoyl]-4(),()-icosadiene-1,3-diol (1) and a steroid ()-methylcholesta-5,-diene-1α,3β,7α-triol (2) were isolated. Other known compounds, 3β,7α-dihydroxy-cholest-5-ene (3), (,24S),5α,-epidioxy-24-methylcholesta-,-dien-3β-ol (4) and (,24S),5α,-epidioxy-24-methylcholesta-,(11),-trien-3β-ol (5). 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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Synthesis of Amphidenolide T1 (1) was studied using palladium-catalyzed hydrogenolysis of alkenyloxiranes as key reactions for constructing vicinal stereogenic centers of synthetic segments 2 and 3. Starting with the allylic alcohol , Sharpless asymmetric epoxidation of , followed by oxidation of the alcohol to the corresponding aldehyde and Horner-Emmons reaction gave the optically active ()-alkenyloxirane 10. The reductive opening reaction of the oxirane was carried out selectively with retension of stereochemistry to give the alcohol 11 in 93% yield. After protection of the alcohol as TBS ether, ester was reduced with DIBAH followed by stereoselective epoxidation afforded epoxy alcohol 12. Then 12 was converted to 14 via regioselective opening of epoxide and cyclization. Coupling with , reduction of the double boond and deprotection of the Piv group formed desired synthetic intermediate 2. Using similar procedures, the allylic alcohol 16 was converted the vinylsulfonyloxiran 18. The reductive opening reaction of the vinyl sulfonyl oxirane was carried out selectively to give the alcohol 19 in % yield. Protection of the alcohol as MOM ether and reduction of the double bond with NaBH_4 gave sulfone 20. And coupling reaction of 20 with 7 by using of n-BuLi and _3・Et_2O afforded 21. Julia methylenation of 21 gave , subsequent deprotection and oxidation furnished the other synthetic intermediate 3. Total synthesis of 1 from the synthetic segments 2 and 3 is under way.

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