Changes in electroretinograms (ERG) due to administration of chlorpyrifos were examined in rats. Male Wistar rats were intraperitoneally injected with chlorpyrifos (0.2mmol/kg body weight), and their cholinesterase (ChE) activities and ERG were measured at various times after the injection. Amplitudes of A and B waves in ERG were more than 50% decreased and latencies of the waves were prolonged 10-20% from 5h to 2d after the injection. At the same time, activities of ChE in plasma, erythrocytes, brain and retinochoroid were remarkably decreased. However, the amplitudes and latencies recovered to the control level more rapidly than the ChE activities of the erythrocytes, brain and retinochoroid.
Injection into rats of 0, 0.002, 0.01, 0.05 or 0.25mmol/kg of chlorpyrifos showed that the chlorpyrifos-induced changes of ERG were dose-dependent, and that a level of 0.05mmol/kg caused a 50% decrease in the A or B wave 5h after the injection.
These results indicate that chlorpyrifos caused abnormal ERG characterized by decreased amplitudes and prolonged latencies of A and B waves and that the abnormal ERG did not always correspond to the decreased retinochoroid or brain ChE activities.

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A yearly ophthalmological examination was carried out in 2 VDT worker groups (A-1 and B-1 groups) and 2 control groups (A-2 and B-2 groups). The 4 groups were as follows; workers routinely engaged in both VDT work and key-punch work at a printing company (A-1 group), researchers or office workers handling VDT irregularly at a chemical company (B-1 group), typesetters at a printing company (A-2 group), and office workers at a chemical company (B-2 group). The examination was commenced in the same year in which the workers of A-1 or B-1 group were introduced to VDT work and was carried out for 3 years.
Comparison between the first and the last examination on subjective refactive power showed that all the groups had lower refractive powers in the last examination than the first one. The workers of A-1 group showed the greatest decrease in refractive power among the 4 groups. The decrease in A-2 group was more severe than in the other 2 groups.
Before VDT introduction, the workers of A-1 group had been engaged only in key-punch work. Information on naked visual acuities of A-1 group 3 years before VDT introduction was also obtained and compared with those in the first and the last examination. The ratio of workers with a severe reduction in visual acuity evidently increased after VDT introduction.
In the first examination, accommodative powers of workers at the printing company were lower than those of workers at the chemical company irrespective of VDT work, and most ophthalmological subjective symptoms were observed in workers of A-1 group. However, no changes in accommodative power or in the number of the subjective symptoms were observed between the first and the last examination in the all groups.
These results indicate that 1) VDT work may be associated with the decline in visual acuity among workers of A-1 group; 2) key-punch or typesetting work at the printing company involved more visual burden than irregular VDT work in the chemical company; and 3) engagement in work of visual nature other than VDT work is an important factor in the establishment of guidelines for VDT work.

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A systematic analytical procedure for dichlorvos (DDVP) and trichlorfon (DEP), organophosphorus pesticides, and furthermore for desmethyl dichlorvos (DM-DDVP), desmethyl trichlorfon (DM-DEP), dimethyl phosphate (DMP) and monomethyl phosphate (MMP), their metabolites and degradation products, was investigated. From the environmental water, drinks and human urine, after salting-out, only DDVP was first extracted with n-hexane and then the others were extracted with acetonitrile-diethylether (1 : 1, v/v) at about 1N by HCl. TLC was performed on silica-gel plate using acetonitrile-water (85 : 15, v/v) and isopropanol-water-28% ammonium hydroxide (75 : 24 : 1, v/v) as development systems. By colorations with 4-(p-nitrobenzyl) pyridine (NBP) and o-tolidine, they were relatively well detected. It was possible to determine DEP, DM-DDVP, DM-DEP, DMP and MMP by FID-GC and GC-MS after trimethylsilyl derivatization of them with N, O-bis (trimethylsilyl) trifluoroacetamide (BSTFA). The detection limits of their aqueous solution were 0.1-3 μg/ml by FID-GC and 0.2-10 μg/ml by scanning mode GC-MS. The coefficients of variation for their spiked urine sample by GC analysis in this way were 2.7-7.6% at 50μg/ml, respectively.

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近年の大規模建築物をめぐる紛争、景観訴訟などを背景として、景観保護のための制限を行う事例が増えている一方で、景観規制の強化に根強い批判がある。景観保護を理由に現行法をこえて権利制限を認める条件については、法学上議論がある。また、景観保護のための権利制限に対する市民の受容可能性は、必ずしも明らかにされてはいない。本研究は、法学上の景観保護をめぐる議論を三つの立場に整理した上で、市民自ら景観保護に責任を有することと関係する、私益と公益の重なり合う利益としての認識、主体間の立場の互換性、相互依存関係といった要因と、景観規制を適用することへの正当性判断および相互拘束ルールが存在する場合に遵守するかどうかの意向との関係性を、一般市民を対象とする意識調査により検証する。空間的広がり、歴史性など景観そのものに関する評価の高低は安定的には有意な影響を与えず、むしろ、受益範囲の広さ、他者の相互拘束ルール遵守意向といった、自らをとりまく他者と対象景観との関係に対する期待のほうが、景観保護の正当性判断や相互拘束ルール遵守意向に影響を与えることが明らかとなった。

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In pest control operations, organophosphorus compounds (OP) have been sprayed as insecticides. Blood cholinesterase (ChE) activities and urinary alkylphosphate levels were measured for both OPsprayers (n=102) and non-sprayers (n=35) in pest control companies, and the relationship between the analytical results and spraying conditions was investigated.
Plasma ChE activities of the OP-sprayers and of the non-sprayers, as well as blood cell ChE activities of the OP-sprayers, were significantly lower than those of employees of chemical factories who served as controls (n=103). Urinary alkylphosphates were not detected in the controls at all but were detected in 83% of the sprayers and in 57% of the non-sprayer employees of pest control companies.
A significant negative correlation (r=-0.34, n=137, p<0.01) between the plasma ChE activities and urinary total alkylphosphate levels was observed in employees of pest control companies. In the case of the employees whose urinary total alkylphosphate levels were 0.1μmol/g creatinine or more, the plasma ChE activities were 25% decreased compared to the control group.
The OP-sprayers showed significantly higher urinary total alkylphosphate levels than the nonsprayers. The OP-sprayers were further divided into two groups. One was sprayers engaged in both cockroach- or fly-control and termite-control operations (sprayers I, n=54) and the other was sprayers engaged in only cockroach- or fly-control operations (sprayer II, n=48). The sprayers I group showed higher urinary diethylphosphate and diethylthiophosphate levels than the sprayers II group, and, inversely, the sprayers II group showed higher urinary dimethylphosphate and dimethylthiophosphate level than the sprayers I group. However, a difference was not observed between the total alkylphosphate levels of sprayer groups I and II.
The levels of urinary alkylphosphates of the OP-sprayers were decreased with the number of days after the last spraying; the workers who sprayed 4 days or more before showed the same urinary levels as the non-sprayers. The passage of time did not affected not only blood cells but also plasma ChE activities.
These results indicate that levels of urinary alkylphosphates reflect recent OP-spraying qualitatively and quantitatively and that urinary alkylphosphate levels are useful as an index of exposure to OP.

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近年のニューキノロン系抗菌薬は, 胆道感染症にも臨床応用されるようになったが, いかなる薬理学的特性を持ったキノロン系抗菌薬が胆道感染症治療に適しているのかは特定されていない。本研究では, ラットを用いて種々の黄疸状態におけるsparfloxacin (SPFX), pazufloxacin (PZFX) とDU-6859aの胆汁中移行について, 各時間帯の胆汁中濃度, 未変化体とグルクロン酸抱合体の比率, および尿中排泄を比較検討した。その結果, 閉塞性黄疸ラットでは, いずれの抗菌薬も胆汁中移行が低下し, 尿中排泄が増加したが, 3未変化体の胆汁中移行はPZFX=DU-6859a>SPFXの順に維持された。EHBRでは, いずれの抗菌薬も未変化体とグルクロン酸抱合体は胆汁中移行が低下した。しかし, 閉塞性黄疸とは異なって, グルクロン酸抱合体のみ尿中排泄が増加した。すなわち, 閉塞性黄疸ではUDP-グルクロン酸のプールが減少していることが関与していると考えられた。Gunnラットでは, 抗菌薬の種類によって胆汁移行が異なり, SPFXのような血清蛋白との親和性の高い抗菌薬は, 血中でアルブミンとの結合の競合が起こり, アルブミンが枯渇するため胆汁中移行が低下した。一方, PZFXやDU-6859aのように血清蛋白との親和性が低い抗菌薬はこの影響を受けにくいため, SPFXより多く胆汁中に移行した。また, PZFXとDU-6859aでグルクロン酸抱合体が検出できたのは, キノロン系抗菌薬を代謝するUDP-glucuronosyltransfbraseはビリルビンとはまったく別のisoenzymeであると推測された。このように, キノロン系抗菌薬による胆道感染症の治療に際しては, 黄疸の状態や肝機能によって, 肝臓における代謝と胆汁中移行が異なることに留意しなくてはならない。

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