Although it has long been known that energy restriction (ER) inhibits tumors and retards aging in rats and mice, its mode of action remains unknown. In rodents, ER alters the rate of age-related changes in physiological indices. Thus, it affects a broad array of age-sensitive parameters. However, present evidence does not indicate which parameters are primary contributors to the deceleration of aging.
Compared to fasting or short-term underfeeding, little is known about the metabolic effects of long-term, life-prolonging ER. We thus investigated the effects of ER on hepatic enzyme activities, including drug-metabolizing enzymes and antioxidant enzymes such as superoxide dismutase and catalase. The catalase activity was found to be higher in ER mice than in control mice both at 12 and 24 months of age. In accord with the high catalase activity, lipid peroxidation in liver was much less in ER mice than in age matched control mice. β-Naphthoflavone, known to induce P-450 related enzymes and xanthine oxidase, was given (ip) to increase lipid peroxidation. The ER was found to inhibit lipid peroxidation after β-naphthoflavone treatment. It was, therefore, concluded that long-term life-prolonging ER increases antioxidant defence, supporting indirectly the free radical theory of aging.
It is well known that ER delays puberty in rodents and has a profound influence on serum hormone levels, including those of prolactin (PRL) and thyroid hormones. However, it remains unknown how these effects are produced by ER. We therefore investigated the effects of ER on the islets of Langerhans in the pancreas and on the pituitary-ovarian axis. In the islets of Langerhans, ER was found to increase the density of α-cells significantly both in 11-and 67-week-old mice. In the pituitary gland in ER mice, the cellular density of PRL-producing cells diminished significantly while that of growth-hormone-producing cells did not. One of the modes of action of ER on the endocrine system is thus concluded to be mediated by changing cellular prpulation.
Since ER decreased PRL-producing cells and PRL plays a key role in mammary tumorigenesis, we investigated whether ER decreased the gene expression of mouse mammary tumor virus (MMTV) in SHN/C3H mice. The SHN strain, which was found to have a new MMTV provirus locus, mtv-4, was used in the study. All of the control mice (n=32) died by 28 months of age and 69 percent of the mice had developed mammary tumors, while 87 percent of the ER mice (n=33) survived and none had developed mammary tumors by that time. mRNA levels of MMTV, both in mammary glands and in uteri, were found to be much lower in the ER mice than in the control mice. Thus, it was concluded that ER suppressed the gene expression of MMTV.
In conclusion, ER was demonstrated to have diverse physiological effects, indicating that ER creates a new steady state, which results in the deceleration of aging (the steady-state hypothesis). Three aspects-effects of ER on growth factors, research on energy-responsive regulatory elements and roles of retroviruses in aging-appear worth investigating in the future.

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The purpose of this report is to summarize data on carcinogenic heterocyclic amines mainly from the aspect of environmental medicine. Since 1977, a new series of heterocyclic amines has been isolated as potent mutagens and they have been shown to be carcinogenic to experimental animals. Among these carcinogens, carcinogenic amino-α-carbolines and amino-γ-carbolines are widely distributed in such components of the environment as airborne particles, rain water, cigarette smoke, diesel exhaust particles and cooked foods. Moreover, most carcinogenic heterocyclic amines are reported to be present in cigarette smoke. These facts suggest that carcinogenic heterocyclic amines are likely to be ubiquitous environmental pollutants. These results also support the hypothesis that carcinogenic heterocyclic amines may be formed through combustion of various materials such as food, grass and petroleum.

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北海道某地域の835人の健常住民(年齢35∼79歳)における血清カロテノイド,レチノール,トコフェロール値と喫煙,飲酒および食品摂取との関連を検討した。血清β-カロチン(BC),α-カロチン(AC),リコピン(LY),β-クリプトキサンチン(BX),ゼアキサンチン(ルテインを含む,ZX),カンタキサンチン(CX),β-トコフェロール(γ-トコフェロールを含む,BT)値は男性より女性が高く,血清レチノール(RE)値は女性で低かった。血清α-トコフェロール(AT)値は性差がみられなかった。重回帰分析では,男性の血清BC,BX,AC,LY,ZX値は喫煙との負の関連をえた。男性の血清BC,AC,BXは飲酒と負相関し,一方,血清RE値は男女共に正相関した。血清BC,AC,ZX値と特に,女性のニンジン,トマト,牛乳,緑葉野菜類などの摂取,および血清BX値とミカン,果汁,果物類摂取と有意な関連がえられた。血清REとAT値は食品摂取と有意な関連はみられなかったが,血清BT値は男性のトマト,果汁摂取と相関した。

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To investigate the biological load of aerobic dance instruction on the body, a blood biological study was performed on 13 female instructors. The values were compared with 10 female healthy controls.
The results obtained were as follows.
1. A significant negative correlation was observed between the total experience of aerobic dancing (in years) and the levels of serum phospholipids. In addition, the numbers of white blood cells and the levels of serum phospholipids, lipoperoxide, uric acid and creatinine were significantly related to aerobic dance instruction time (years).
2. The levels of serum CPK, aldolase, GOT, BUN and creatinine in the aerobic dance instructors were significantly higher than those in the controls.
3. The levels of serum CPK, uric acid, BUN, creatinine and Ca increased significantly after an intermediate class lesson (about 60 minutes). In addition, the numbers of white blood cells also increased after the lesson, but not significantly. Moreover, Significant decreases of the mean corpusucular volume and serum Mg were observed after the lesson.

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The rapid increase of the proportion of older persons in society has made the problem of medical costs more important. Although medical cost-sharing for those aged 70 or more is decided by their medical costs and by the current proportion of such persons in the Society, it is not constant throughout the Society.
The study evaluated the contribution ratio of medical cost-sharing for those aged 70 or more to the financial balance of the Society. In addition, characteristics of the Society associated with medical cost-sharing for those aged 70 or more were analyzed.
The results are as follows.
1) Medical cost-sharing for those aged 70 or more was the greatest factor in the financial balance of the Society with a contribution ratio of as much as 55.2%.
2) Multiple regression analysis disclosed that dependent ratio, the average monthly salary, the area, the rate of those aged 70 or more and the average age of the Society members are significant in medical cost-sharing for those aged 70 or more.
3) Dependent ratio and the average monthly salary are the most important characteristics among those associated with medical cost-sharing for those aged 70 or more. A higher dependent ratio and a lower average monthly salary are related to higher cost-sharing. This is also related to geographic factors as cost-sharing in western Japan is higher than in eastern Japan. The lower rate of those aged 70 or more and the higher average age of the Society members are related to the higher cost-sharing.

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The concentrations of urinary tin in healthy adults in Aichi prefecture were determined by anodic stripping voltammetry over a period of three years (1986-1988), to obtain the normal tin level in urine and to elucidate the influence of environmental alterations on health conditions in the future.
In addition to the above-mentioned method, the relationship to life style, dietary habits, smoking habits and living environment were studied, and the following results were obtained.
1) The mean±standard deviation of urinary tin levels for males was 3.7±2.2 (μg/g creatinine), and 5.9±3.0 (μg/g creatinine) for females. The data showed logarithmic normal distributions in both sexes, and the maen concentration for females was significantly higher than that for males (P<0.001). The levels of urinary tin concentrations significantly increased according with age.
2) Significant correlations of urinary tin concentrations between two observations were noticed in repeated by observed subjects.
3) As to the dietary habits, fish intake increased the urinary tin concentration, but no definite association with canned-food intake was observed.
4) Smoking habits and living environment also showed a tendency to increase the urinary tin concentration, but the difference was not statistically significant.

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The digestibilities of nutrients and energy in Shiitke mushrooms (Lentinus edodes) was measured in healthy adult males. A test diet was given for 5 days after 5 days on a basal diet which supplied 40g/day of protein and 45kcal/kg/day of energy. The test diet was identical with the basal diet except that shiitake was incorporated. Digestibility was calculated by the difference of fecal output between the test period and the basal period. The results obtained were follows:
1. Shiitake 60g/day intake level
Digestibility of protein was 69.3±11.2%.
Digestibility of fat was 66.6±24.9%.
Digestibility of carbohydrate was 55.7±10.5%.
The ratio of the total available energy to intake energy (Net Energy Availability) was 55.4±15.4%.
2. Shiitake 40g/day intake level
Digestibility of protein was 85.5±23.8%.
Digestibility of fat was 70.0±90.1%.
Digestibility of carbohydrate was 65.8±13.1%.
The ratio of the total available energy to intake energy (Net Energy Availability) was 67.4±25.9%.

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The purpose of our work is to develop an estimation method for odor thresholds on the basis of physicochemical properties of odorous compounds. In this report, we examined the correlation between odor thresholds (C_th) and the saturated vapor pressures (P_vp) of various odorants.
Results.
1) There were very good correlations between P_vp and k. k represents an indicator of lipid affinity. In our earlier report, k was obtained by the analysis of the gas chromatography with a column packed with a support coated by a phospholipid. Accordingly the correlations show that P_vp may be an indicator of solubility into the lipid phase.
2) It was found that correlations between P_vp and C_th were very good in several homologous series of aliphatic compounds. However inoized substances, such as acids and amines, and sulfur compounds had no good correlations.
3) In odorants having more than 3-5 carbon atoms, odor thresholds of normal types were higher than those of iso types.
4) In the series of amines, the relationship between C_th and P_vp depended upon the length and the number of alkyl chains combined with the contained nitrogen atom.
5) In the series of alcohol and aldehyde, the decrease of C_th in the rate became smaller with the decrease of P_vp.

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Glu-P-1,Glu-P-2は,グルタミン酸熱分解物から単離精製された変異原性発癌性複素環状アミンであり,これまでに加熱食品,タバコ煙などに検出されている。本研究では,高速液体クロマトグラフを用い,Glu-P-1,Glu-P-2,及びそのN-アセチル化物の尿中への一日排泄量の測定を行った。排泄量には個体間でのばらつきが認められたが,これらの物質は全検体中に検出された。Glu-P-1,N-acetyl-Glu-P-1,Glu-P-2,N-acetyl-GluP-2の尿中一日排泄量の平均値は,それぞれ,0.53,0.41,2.12,4.60pmolであった。組織におけるN-アセチル化能を検討する目的で,さらにin vitroの実験を行った。その結果,肝及び腎由来の細胞可溶性画分に,Glu-P-1,Glu-P-2のN-アセチル化活性が示され,肝のみでなく,それ以外の組織もこれらの物質のN-アセチル化に関与していることが示唆された。以上の結果は,Glu-P-1,Glu-P-2が,肝や腎などの代謝臓器において一部N-アセチル化を受け,N-アセチル化物とともに尿中に排泄されていることを示すものである。Glu-P-1,Glu-P-2,及びそのN-アセチル化物の尿中への一日排泄量は,人体への暴露量を評価する際の有用な指標となると思われる。

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「嫌煙権」意識は健康意識の一指標として有用である。そこで,われわれは大阪府下D市の住民(成人男女1,500名)を対象にアンケート調査を行い,ライフスタイル(日常生活習慣)と「嫌煙権」意識の関係を定量的に検討した。第一報において説明したように,「嫌煙権」意識は知識,意見および態度の三側面に分けて把握した。また,ライフスタイルの良否はBreslow,Bellocや森本らの研究成果をふまえ,8の日常生活習慣項目(喫煙,飲酒,朝食の摂取,睡眠時間,栄養バランス,労働時間,運動,ストレス)の合計得点(0-8点)によって一元的に把握した。本報では「嫌煙権」意識の意見側面とライフスタイルの関係,および「嫌煙権」意識の三側面とライフスタイルの関係について検討を加えた。以上の検討は,喫煙の有無と性別によって層別化された四群について行われた。その結果,女性(「女子喫煙者」「女子非喫煙者」)では「嫌煙権」意識の意見側面と知識側面,および,知識側面とライフスタイルの間に関連性が見られた。男性(特に,「男子喫煙者」)では意見側面と,ライフスタイルの間に関連性は見られなかった。これらの結果は,健康教育が女性の「嫌煙権」意識(特に,知識側面や間接的ながら意見側面)の向上に役立つ可能性を示唆しているものと考えられる。また,「女子喫煙者」群,「女子非喫煙者」群,「男子非喫煙者」群では,態度側面は,意見側面,知識側面,ライフスタイルとの間に関連性はなく,むしろこれら以外の要因との間に関連性が見られた。これは,「嫌煙権」意識の態度側面は健康教育によって改善することが難しいことを示唆したものと考えられる。

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