The aims of the present study were to observe the daily habituation to night sleep in a laboratory environment and to make clear the daily and individual sleep variations by using polygraph parameters, including electroencephalography (EEG). Sleep EEG records were obtained from a subject who slept ten successive nights, and from six subjects who each slept one night in the laboratory. The parameters used were as follows: sleep stage %, sleep latency (SL), REM latency (RL), number of stage shifts, subjective sleep, integral EMG, and slope (a) and intersect (b) of a regression equation used to estimate the sleep depth against sleep time.
Stage WAKE and SL, slope (a), intersect (b) and the mean depth of sleep were found to become stable from the fifth night. Stage MT, the number of stage shifts, and integral EMG increased significantly from the fifth night and later, showing p<0.01, p<0.01, and p<0.05, respectively. Judging from these findings, the sleep habituation of the subject in the laboratory was completed within the first four nights.
Coefficients of variation of sleep stage 2 and stage REM of the ten-nights' EEG were the lowest among all the sleep parameters examined. Almost all the parameters of day-to-day sleep of the subject who slept for ten successive nights in the laboratory showed smaller variations than those of the other six subjects. It may be concluded that the mist effect on sleep could be assessed more precisely by using an individual repeatedly than by using a group of subjects.

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To clarify the maternal-fetal transfer of cadmium across the placenta, cadmium was determined in 21 paired samples of maternal blood, placenta and umbilical cord blood obtained at delivery from pregnant women who did not smoke and had no particular exposure to cadmium compounds in their history.
Cadmium was detected in all the samples. In both maternal blood and umbilical cord blood, the cadmium concentrations in the red blood cells were remarkably higher than those in the plasma. The cadmium concentration in the umbilical cord blood was significantly lower than that in the maternal blood, suggesting that the placenta migth effectively block the transfer of cadmium to fetuses in pregnant women. The placental cadmium concentration was the highest in the samples determined. The ratios of placental to maternal blood cadmium concentration were very large, indicating that cadmium preferentially accumulates in the placental tissues. On the other hand, the ratios of umbilical cord blood to placental cadmium concentration were very small, indicating that the placenta constitutes an effective barrier against cadmium; that is, the placental cadmium is hard to transfer to fetuses in pregnant women. The significantly positive correlations between maternal blood and placenta, between placenta and umbilical cord blood and between maternal blood and umbilical cord blood in terms of the concentrations of cadmium suggest that the amount of cadmium accumulated in placenta and transferred from mother to fetus is strongly influenced by the cadmium body burden of the mother.

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Diving profiles of fishermen divers in the Izu Islands were investigated and recorded by DDR (Diving Data Recorder).
Consumed air volume during diving work was also checked in each dive and the work load was measured by Vo₂ during diving.
It was recognized that divers repeatedly experienced extreme descents and ascents, that were accompanied by increases of oxygen consumption. This suggested that the load of their work was far beyond that of sports divers.
The particular diving method used, called the "Qikomi Gyoho method" is to repeatedly dive several times to catch fish. Each bottom (diving) time is rather short and the depth changes from deeper to shallower areas gradually. This profile is considered to be a safe diving method for the prevention of DCS (Decompression Sickness). Hawever, stapping for decompression during ascent is sometimes required to prevent DCS according to analysis of the diving profiles. It is pointed out that the risk of DCS still remains with this diving method.

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A pilot study to improve unhealthy life habits of thirty middle-aged male clerical workers (45±3.58 yr.) with mild health disorders such as hypertension, hypercholesterolemia, diabetes mellitus and fatty liver was carried out. Under prohibition of smoking and alcohol intake, they spent five nights and six days at a hot spring resort, taking part in planned health training programs which included aerobic training, hiking in forests, hot spring baths, cooking practice and lectures about healthy life, controlled by medical, dietary and physical training staffs.
To evaluate the short-term effects of these activities, body weight, blood pressure, serum lipid (total cholesterol, high-density-lipoprotein cholesterol, triglyceride, total free fatty acid and phospholipid), blood sugar, uric acid, γ-glutamyl transpeptidase(γ-GTP)and glutamic-oxaioacetic transaminase (GOT) were examined early in the morning of the second (before) and the fifth (after) days, and then their impressions of these recreation activities were monitored by questionaires on the sixth day.
By t-tests of all before-and-after data, it was shown that mean values of body weight, systolic blood pressure, high-density-lipoprotein cholesterol, triglyceride, phospholipid and γ-GTP were improved, but fasting blood sugar, uric acid and GOT were not improved. In cornparrson of blood pressure levels, the hypertensive group (n=9) showed lowering in both systolic and diastolic blood pressure, though the normal group (n=10) had slight elevation. In addition, in the hypercholesterolemic group (n=11, ≥220mg/dl) mean total cholesterol values decreased, conversely in the hypocholesterolernic group (n=6, <180mg/dl) they increased. Moreover, the obese group (n=15, obesity index ≥120%) showed greater decreases of body weight, triglyceride and phospholipid than the non-obese group. From questionaires, it was confirmed that through these recreation activities most participants found mental and spiritual satisfaction, in spite of heavy physical loads.
The short-term recreation activities under a stressless environment seemed to maintain the function of homeostasis in the body, but further investigation is needed to examine the relation between the contents of diets and physical activities, and to follow the long-term effects on the participants.

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健常な男性従業員312名(年齢:20～58歳)を対象として,その血清α-,β-カロチン量への飲酒量と喫煙量の影響を検討した。その結果,飲酒者は非飲酒者に比較して血清α-,β-カロチン量が共に低く,喫煙者も非喫煙者に比較して有意に低かった。また,喫煙者では,飲酒量の増加に対応して特に低くなる結果がえられた。一方,緑黄色野菜類や果物類などの摂取頻度の増加に伴い血清α-やβ-カロチン量は増加したが,飲酒者や喫煙者ではこれらの摂取頻度が特に低くはなく,飲酒および喫煙が血清α-およびβ-カロチン量を低下させる作用を有するものと推察される。

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幼若ラットに亜セレン酸ナトリウムを1回皮下投与し,白内障を誘発した。この亜セレン酸誘発性水晶体毒性はグルタチオン合成抑制剤の前投与により増強された。SDS-ポリアクリアミドゲルを用いて,電気泳動分析した結果,白内障水晶体中に高分子蛋白凝集物質と蛋白分解物質の存在が分かった。さらに水溶性水晶体蛋白に亜セレン酸ナトリウムを加えて3日間インキュベションすると,水晶体蛋白液の混濁度の増加,SH基含量の減少および高分子蛋白凝集物質と蛋白分解物質の出現が認められた。
以上の所見から,亜セレン酸ナトリウムは水晶体蛋白のSH基の酸化を起こし,水晶体蛋白の変性および不溶性高分子物質形成をもたらし,白内障を誘発するものと考えられる。

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最近の死因別死亡率をみると,これまで第3位であった心疾患が,S.60年より第2位の脳血管疾患と入れ替わり,第2位心疾患,第3位脳血管疾患となった¹⁾。この死亡率の逆転は,医療技術の向上もさることながら,食塩の摂取量の制限(減少)や栄養改善等,脳血管疾患対策の奏効による脳血管疾患の減少,ならびに,食生活の欧米化の浸透により,動物性脂肪摂取量の増加等に起因する,中高年齢層におけるアテローム性動脈硬化を中心とする心疾患による死亡率の増加,によるものと考えられる。このアテローム性動脈硬化を中心とする心疾患による死亡率の増加は,心疾患の中でも,特に心筋梗塞や狭心症のような,虚血性心疾患の増加が著しいことからも明らかであると考えられる。加えて,第3位の脳血管疾患においても,これまでの脳出血を中心とするものから脳梗塞を中心とする疾患に変わっている。脳梗塞,とりわけ皮質枝系脳梗塞は,アテローム性動脈硬化の関与する疾患とされる。これらアテローム性動脈硬化に基づく疾患の成因は多元的要因にわたっているが,現在の活発な研究の渦中にあるものの1つにリポ蛋白ならびにその構成蛋白であるアポ蛋白の代謝があげられる。
我々は,このリポおよびアポ蛋白代謝に着目し,脳卒中易発性高血圧自然発症ラット(SHRSP)をモデル動物として,動脈硬化性疾患発症機構の解明あるいは予防を志向して研究を進めてきた。そして,これまでに,高脂肪・高コレステロール食(High-fat and high-cholesterol diet: HFC食)負荷により反応性高脂血症を誘導した際のリポ蛋白,特に高比重リポ蛋白(High density lipoprotein: HDL)亜分画の変動²⁾,長期HFC食負荷による慢性的高脂血症におけるリポ蛋白を中心とする血清脂質の変動3)について報告した。
今回は,アポ蛋白レペルに注目して,我々の研究室で確立した,Laurell法⁴⁾に準拠したRocket免疫電気泳動によるアポ蛋白の定量法⁵⁾を使用し,HDLの主要構成蛋白であるアポ蛋白A-I, A-IV, E (apo A-I, A-IV, E)のHFC食負荷による変動を調べた。

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An improved and simplified Head Space Method was devised for measurement of the concentration of odorants dissolved in waste water, and this method was examined to determine whether it was applicable for this purpose or not.
This method is taken into consideration the variableness of liquid concentration and of gas pressure resulting from the volatilization of odorants and aqueous vapor to the atmosphere.
By this method, the constants of hydrogen sulfide, dimethylsulfide and trimethylamine were measured under various temperatures and pHs. As a result of comparison with the measured values obtained by the Stripping Method and those from the heretofore used Head Space Method, this method appeared to be fairly applicable.

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ゴミ焼却場,し尿処理場,下水道ならびに地下鉄工事などの地下管渠や汚水槽内での作業時に,事前に内部の気中濃度の測定から安全を確認した上で坑内や槽内に入った作業員が急性の中毒事故で倒れる例が多発した¹⁾。従来から,これらは酸欠事故とされてきたが,急性の硫化水素事故であることが明らかとなり¹⁾,労働省は,昭和57年5月に労働安全衛生法を改正し²⁾,指定危険場所での濃度測定と換気および作業員教育を義務づけたが,同様の中毒事故は後を断たない。
硫化水素は,有機物の嫌気性分解によって発生し,対空気比重が1.19³⁾と大きく,底部に滞留する。また,水に対する溶解度も0.38g/100g-w (20℃)⁴⁾と比較的大きく,坑内や槽内に多量の水が存在する場合には,空間濃度の測定のみでは,安全の確認にはなりえない。すなわち,汚水や底泥中には多量の硫化水素が捕捉されでおり,急激な攪絆によって,致死量を超える硫化水素が瞬時に空間内に放散されることが報告されている¹⁾。
このことは,閉鎖系の作業現場では,重大な事故発生を暗示しており,作業者が坑内や槽内に入る前に,汚水や底泥中の硫化水素量を測定,把握するとともに,最大発生時を想定した換気等の予防対策を講じることの必要性を示している。
一方,水中や底泥中に存在する硫化水素の測定方法としては,従来から,よう素滴定法5),メチレンブルー吸光光度法⁵⁾による硫化物の測定値から硫化水素へ換算する方法が用いられている。しかし,硫黄の存在形態は多様で,この換算値は必ずしも存在する硫化水素量とは対応しない。また,硫化物の直接測定は,共存物質の影響を受けやすく,硫化水素だけを選択的に測定できる方法としては,精度的に確立された方法はなく,空気置換法の検討⁶⁾もなされているが,精度などの問題点も残されている。そこで,本研究では,実際の汚水および底泥中に存在する硫化水素量を簡易的,かつ高い精度で測定できる方法として,汚水のストリッピングによる測定法を新たに検討するとともに,作業時における硫化水素の最発生時を想定して汚水中からの発散量を推定し,この値をもとに坑内作業中の気中の硫化水素濃度を安全なレベルに保つための必要換気量を算出した。
なお,本測定に用いた試料は,昭和62年4月に,東京都の下水道管渠内の清掃作業開始直後に人身事故⁷⁾の発生した場所においで採取したものである。

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It is well known that taurine, a final metabolite of sulfur-containing amino acids, plays an important role in bile acid metabolism and that it also has a moderately hypotensive effect. Moreover, it has recently been revealed that taurine shows a hypocholesterolemic effect in animals with experimentally induced hypercholesterolemia. However, the hypocholesterolemic mechanism remains unresolved.
Stroke-prone spontaneously hypertensive rats (SHRSP) easily develop hypercholesterolemia when fed a high-fat and high-cholesterol diet (HFC diet). In our previous paper, we reported changes in the concentrations and distributions of serum lipoproteins and apolipoproteins in hypercholesterolemic SHRSP and Kyo: Wistar rats (WKY) induced by HFC feeding.
In this paper, to elucidate the mechanism of the hypocholesterolemic effect of taurine, we investigated the effects of taurine on concentrations and distributions of serum lipoproteins and apolipoproteins in hypercholesterolemic SHRSP and WKY induced by HFC feeding.
The results obtained were as follows:
1) The hypocholesterolemic effect of taurine in hypercholesterolemic SHRSP was remarkable in comparison with that in hypercholesterolemic WKY.
2) The hypocholesterolemic effect of taurine was mainly due to a marked suppression of extreme elevations of cholesterol contents in the VLDL and IDL fractions of both strains. This was associated with a decrease in the elevated contents of apo B and apo E which are major components of VLDL and IDL. This suppressive effect was more obvious in SHRSP than in WKY, which explains the greater hypocholesterolemic effect of taurine in SHRSP. It could be that, as a result of taurine administration, the catabolism of cholesterol to bile acid in the liver is accelerated, followed by a decrease of the hepatic cholesterol pool, resulting in a suppression of the synthesis and/or secretion of VLDL (β-VLDL) in the liver.
3) The hypocholesterolemic effect of taurine was also observed in the LDL fractions of both strains, but the effect was not as strong as that observed in the VLDL and IDL fractions. This effect might be attributable to suppression of the synthesis and/or secretion of LDL in the liver and a decrease in the elevated content of apo E HDL (HDLc) which spans two density fractions (the LDL and HDL fractions).
4) In HDL fractions of both strains, the decreased content of apo E HDL (HDL1 and HDLc) was even lower, whereas the decreased apo A-I content in the HDL fraction of SHRSP was significantly restored and the cholesterol level was slightly elevated. However, the decrease of apo E HDL which could be considered to be a protective or anti-atherogenic lipoprotein seems to be unfavorable for the antiatherogenic effect of taurine. This discrepancy will be an important subject of study in the future.

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Serum retinol and tocopherol concentrations in 419 males and 478 females, aged 10 to 49 years, were determined by an HPLC method. Then their relationships to serum lipid concentrations and smoking and drinking habits were examined. Retinol levels were higher in males than in females but tocopherol showed little difference by sex. The sex differences in age-related serum levels of retinol and triglyceride (TG) were similar to those of tocopherol and total cholesterol (TC), respectively.
Retinol had a significant correlation with TC and TG, with coefficients of 0.20-0.29 (p<0.001). These were smaller than those of tocopherol (R=0.32-0.52, p<0.001) both in males and females, suggesting that it had a higher susceptibility to factors other than serum lipids than tocopherol did.
Both the retinol and tocopherol levels were significantly higher in the groups with smoking and drinking habits than in the groups without them among the males aged 30 years and over. Furthermore, the retinol level was positively dependent on the daily consumption of both cigarettes and alcohol, whereas tocopherol was dependent on the consumption of alcohol. Multiple regression analysis showed that smoking and drinking habits had statistically significant effects on the serum retinol level independent of other factors and that their effects were greater than those of TC and TG. Tocopherol was affected most by TC and TG and then by drinking habit. Less significant but similar results were obtained for the females of the same age group.
Since smoking and drinking habits, known to be carcinogenic, was related to increases in the serum levels of retinol and tocopherol, it would appear to be necessary to study the relationship of these serum levels with tissue levels of vitamins A and E to examine their protective effects against carcino- and atherogenesis.

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We investigated the differences in manganese concentration and distribution in the brains of rats administered MnCl₂ perorally, intravenously and intraperitoneally for one week.
Forty two male Wistar rats were divided into eight groups, designated A to H. Groups A (n=5) and B (n=7) were maintained with synthetic diets, with 50 and 1000mg manganese per kg diets, respectively. Groups C (n=5), D (n=5) and E (n=5) were administered manganese intravenously with dosages of 0.088, 0.88 and 2.2mg/kg.b.w./day, respectively. Groups F (n=5), G (n=5) and H (n=5) were administered manganese intraperitoneally with dosages of 0.088, 0.88 and 2.2mg/kg.b.w/day, respectively. Four brain regions (cerebrum, cerebellum, basal ganglia and the remainder) were analyzed by atomic absorption spectrophotometry for manganese.
The manganese concentrations in basal ganglia were increased proportionally to the administration dosages in intravenous administration groups (C, D and E). At the highest dosage of manganese administration, manganese concentrations in cerebrum and basal ganglia were higher with intravenous administration of manganese than with intraperitoneal administration. In addition, manganese concentrations were hardly increased in peroral administration groups. Therefore, we suggested that basal ganglia are vulnerable to manganese exposure and that liver and intestine might play the important roles in the reduction of manganese accumulation in the central nervous system.

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In order to clarify synthetically the situation concerning air pollution by suspended particulate matter (SPM) in the vicinity of the Meishin Expressway, polycyclic aromatic hydrocarbons (PAHs), which are typical substances adsorbed on SPM, were determined by the high-performance liquid chromatography method, and the distribution of the PAHs concentrations was examined.
The concentration of benzo (a) pyrene (B(a)P) at a point 60m from the road edge was 2.93ng/m³ (9.11μg/g dust). The concentration of benzo (ghi) perylene (B(ghi)P) was 6.62ng/m³ (20.6μg/g dust) at this point, being the highest of all the PAHs that were analyzed in this study.
The concentrations of PAHs that were contained in 1g of dust were the highest in the SPM fraction from 0.7 to 1.6μm in diameter. The concentrations of PAHs that were contained in particles under 5.4 μm in diameter, and which are absorbed extremely easily into the lung, occupied more than 90% of the concentrations of PAHs that were contained in the total SPM.
When there was a high frequency of perpendicular wind, the concentrations of PAH_s in SPM fractions under 1.6μm in diameter showed a marked tendency to have a clear concentration-distance profile, but when there was a high frequency of parallel wind, it was observed that these concentrations at a point 120m from the road edge were much higher than at the road edge.
The correlation coefficient between the concentrations of B(a)P and the traffic volume of large vehicles was elevated with the increase of distance from the road edge and was statistically significant at a point 290m from the road edge.

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