Thanks to the recent development of parenteral and enteral nutrition, it has now become possible to provide adequate nutrition from vein for a prolonged period of time.

Accordingly, there was been an increasing number of clinical cases who are solely depending on such artificial nutrition (AN), which has posed various unforseen problems. Among these problems, recent attention has been focused on the supply of trace elements, specially of zinc. About 15 years ago, a very small proportion of the patients on prolonged parenteral nutrition, developed characteristic skin lesions over face, scrotum, and perianal area. These lesions later extended to the extremities particularly in the joints.

Stomatitis, glossitis and loss of hair are usually observed. There also occurred enteritis-like symptoms such as abdominal pain and diarrhea. We first demonstrated that zinc deficiency was responsible for those characteristic lesions. Since then, metabolism and physiological role of zinc in human body have been extensively studied, and significant progress was made in this field.

The determinations of a trace amount of molybdenum, tungsten and vanadium by high-performance liquid chromatography are proposed.

The molybdenum and tungsten in the form of tiron ( 1, 2-dihydroxybenzene-3, 5-disulfonic acid) chelates were separated on a C₁₈-bonded phase column with methanol-water containing tetrabutylammonium bromide (TBA-Br) as a mobile phase, and were simultaneously determined at 315 nm.

The vanadium in the form of PAR (4-(2-pyridylazo)-resorcinol) chelate was also separated in the same way as the determination of molybdenum and tungsten, and was spectrophotometrically determined at 555nm.

These techniques were applied successfully to the analysis of plant materials after wet ashing of the sample and extraction of the molybdenum and tungsten asabenzoinoxime complexes or the vanadium as the N-benzoyl-N-phenylhydroxylamine complex.

Bromine (Br), one of halogen elements, exists naturally in all plants and animals. Since many brominated compounds have been used for the fumigation of foods and feeds in recent years, there is a possibility for Br to accumulate in animal body through feedstuffs. However, there is little information concerning the metabolism of Br in livestock.

The flow rate and the level of total Br in digesta of sheep were determined with La as an unabsorbed reference substance using the method of neutron activation analysis.

The levels of Br were about 40ppm in feed, 1097ppm in the duodenum digesta, 308 ppm in the ileal digesta and 15ppm in faeces. The daily flow or Br was 30mg from feed, 427mg in the duodenum, 75mg in the ileum and only 2.9mg in faeces. This study demonstrated that a large amount of Br was secreted endogenously and reabsorbed rapidly in the small intestine, as a result, Br was accumulated to some amount in a sheep body.

It is already well known that selenium (Se) and vitamin E are important for newborn・ animals in terms of either preventing muscular dystrophy or maintaining normal growth rate. There has not been enough information reported as yet, however, about the changes in the nutritional conditions of Se and vitamin E in the dam and calf in the periods before and after parturition. This study was conducted to investigate maternal and neonatal levels of Se and α-tocopherol (α-Toc) and the growth of their newborτ1 calves during their suckling period in two groups of grazing cows which were kept at different Se levels; a low-Se group (Se-) which was grazed on Se deficient grass (around 0.02 ppm DM) and a Se-sufficientgroup (Se+) which received ruminal Se pellets.

Se concentration and glutathion peroxidase activity in blood in the cows did not show any remarkable diff erencとbetweenpre and postparturition. New born calves. from both groups of Se-and Se+ showed Se and GSH-Px levels of about 120 to 190 percent of their dam cows on the day of parturition. In contrast,α-Toc levels in both groups showed values lower than one half of their dam’s on the day of parturition. As for the growth rate of calves, there was no significant difference in body measurement between the two groups at birth and at four months of age, but significant superiority in body weight, withers height and chest girth was observed in the Se+ group at the weaning period.

Sixty-nine brown rice (Oryza sativa L. japonica) samples, composed of 18 different cultivars, were collected from 37 sites of Japan, and their selenium contents were determined by a fluorometrical method. Total mean ± standard deviation for the 69 samples were 43 ± 27 ng Se/g. The selenium levels were found to vary by the sites where rice was grown, but least to vary by the cultivars. A value of 127 μg/day/ capita was obtained as average selenium intake of Japanese by a calculation based on the data obtained in this study and the food consumption pattern as revealed in the annual nutrition survey conducted by the Ministry of Health and Welfare, Japan. Selenium intake from rice was estimated to account for only 5-10μg/day/ capita; rice is not a principal selenium source in Japanese diet.

As commercial diet was no.t formulated in yellowtail Seriola quinqueradiata culture, raw fish are employed. However, long term feeding of sardine Sardinops melanosticta causes nutritional disease which accompanies retardation of growth and high mortality. In the present study, feeding trial was carried out in order to prevent the nutritional disease.

The nutritional disease raised in young fish less than 250g in initial body weight. The pathological symptoms such as necrosis of the tublar epithelia and numerical atrophy of the hepatopoietic tissue in the kidney, low level of hematocrit and serum albumin, blood corpuscular resistance were not found in the group fed 0.5% of kelp Laminalia digitata meal and/or 1 % of vitamin mixture.

The dietary kelp and vitamin mixture effectively prevented the nutritional disease. While the preventive effect of kelp on the disease could not be explained, the effect seemed to be different from that of vitamin mixture.

The inhibitory effects of the extracts from anti-"Oketsu"drugs, Bochu, Shachu, and Suishitsu on the aggregation of human platelets were examined.

1) Hot water extracts of BochU, Shachu, and Suishitsu inhibited the aggregation of human platelets induced by adenosine diphosphate (ADP) and epinephrine.

2) Fraction 2 separated from ShachU extract using Sephadex G-50 showed the remarkable inhibition of platelet aggregation by ADP.

3) Fraction 1 (high molecular fraction of sugar) separated from Suishitsu extract using Sephadex G-50 inhibited remarkably the platelet aggregation by ADP.

Thrombtic diseases have been increasing more and more recent years. Attempts to control the platelet aggregation which is one of main factor of them has been taken a notice of in the clinical field. Ohta et al. was found that the oyster extract repressed the platelet aggregation activity strongly but the activities were not revealed in another food stuffs. In this study, we investigated the platelet aggregation control ability in various food stuffs. The result was that the low molecular fractions, especially nucleic acid related substances, had the effects of platelet aggregation control and the activity was emphasized when they were boiled. It was suggested that substrates having platelet aggregation control effect were increased during boiling process by enzyme sand other things.

The effects of dietary oyster extract on platelet aggregation were investigated. The inhibition effects of oyster extract was found in Wister male rat platelet aggregation in vivo as well as human platelet aggregation in vitro.

Effects of oyster extract was investigated in alloxan diabetes rat. These animals were fed on different oyster level (20mg/kg/day, 200mg/kg/day) diet for 3 weeks. A remarkable improvement of platelet aggregation and blood glucose levels was obserbed.

The taurine and zinc (Zn²⁺) contents in oyster extract show high level (12.7g/100g, 61.0mg/100g, respectively). Three group animals were fed on component of oyster (1. Taurine, 2. Zinc chloride, 3. Taurine and zinc chloride) added diets for 3 weeks. No significant change was obserbed in platelet aggregation and glucose tolerance test. It was not affected in addition of the component of oyster, but was very effective in administration of oyster extract. From the above results, it is suggested that effects of oyster extract against alloxan diabetes and platelet aggregation is based on potentiation by components of oyster extract.

In patients with diabetes mellitus, the threshold of taste was determined to a study which related this parameter to their diabetic status and complications. In 109 normal subjects and 112 diabetics, the threshold of taste in chorda tympani nerve area of the tongue was measured by an electrogustometer.

In both groups, the taste threshold increased with aging. However, the taste threshold in diabetics of 30 to 60 years of age, showed a statistically significant increase as compared with that in normal subjects of the age. In diabetics, the longer the duration of diabetes mellitus, the more the taste threshold increased. Further in diabetics of poorer metabolic control, the threshold of taste showed a higher level. Patients with symptomatic neuropathy had a statistically significant increase of the taste threshold as compared with patients without such clinical symptoms. The taste threshold was found to increase with progression of diabetic retinopathy. Furthermore, even in the patients without retinopathy, proteinuria or clinical symptoms of neuropathy, whose Achilles’s reflex is normal, the taste threshold showed a significant increase as compared with those of age matched normal subjects.

These findings indicate that the somatic nerve function as indicated by gustatory threshold testing precede other diabetic complications, and suggest that this examination in diabetics may be useful as predictor of the complications in diabetes.

In oyster administered rat, Li content in brain increased about 8 times compared with control group.

And then, we experimented about the regulation of serotonin metabolism in rat administered with the component of oyster or oyster extract itself.

1) MAO activity increased in both Li²⁺ and taurine added group.

2) In alloxan diabetes rats, high taurine level in liver decreased in oyster administered rats.

3) On the other hand, low taurine level in brain increased.

From these evidence, it was not so affected in sole administration or addition of the component of oyster.

But it was ve巧f effective in administration of oyster extract.

An open clinical trial of oyster extract, which contains a large quantity of zinc, 2-3g per day, was performed in 10 inpatients with hebephrenia. These patients were maintained on antipsychotic drugs without dosage modification during 3 months.

To evaluate its clinical effect, various tests such as Rorschach Test, Minnesota Multiple Personality Inventory, Wechsler Adult Intelligence Scale, Uchida-kraepelin Psychodiagnostic Test and Brief Psychiatric Rating Scale were carried out before administration and after 3 months of administration of oyster extract.

Almost all negative symptoms improved to some extent in 10 cases for 3 months, and especially the improvement of loss of drive and intellectual impairment were prominent. Favourable clinical improvement was achieved in two subchronic cases.

The values of Zn and Cu in serum and 24-hour urine, when determined by atomic absorption spectrophotometry, showed remarkable changes between two groups, which were separated from the point of 10 years duration of illness into the subchronic and chronic groups.

Zinc levels were low in the chronic group before administration, and became lower in serum and urine of the subchronic group after administration of oyster extract accompanying clinical improvement. High serum Cu levels were determined in 2 cases corresponding with positive symptoms.

The values of serum Cu/Zn levels were low in the subchronic group before administration and the increase of the value of ratio in the subchronic group after administration of oyster extract was four times greater than that of the chronic group.

Thus, Zn-Cu dysmetallosis is suspected to be a possible pathological factor of hebephrenia.

Etiological factors of many neuro-psychiatric diseases are yet unknown, their treatments are very difficult, especially amyotrophic lateral sclerosis (ALS) and hebephrenic form of schizophrenia.

While serving in Wakayama Medical College, I studied many caces of ALS, which spread throughout the southern part of Kii peninsula. So I tried to elucidate the etiological factors of ALS. The water of Kozagawa river contains very little minerals: Ca and Mg. By adding Ca and Mg in the drinking water of patients, outbreak of disease certainly decreased.

In Guam, there are also many cases of ALS discovered, and their drinking water also contains very little Ca.

According to our clinical experiences, we advised them to add Ca in their drinking water. After they did that, ALS cases clearly decreased.

In Guam, Mn content in the soil is eighty times as much as the average in Japan. In the period of World War II, 150 Chamorros were working in Mn mine, and 70 workers fell ill with ALS and Dementia Parkinsonism.

Dr. Yase and Dr. Yoshimasu investigated trace metals in the ALS brains in Kii Peninsula and Guam by means of Neutron Activation Analysis (NAA). They discovered that large amounts of Ca, Mn and Al are precipitated in motor neurons. According to these observations, Dr. Yase proposed that ALS are by metal induced calcifying degeneration of motor neuron system.

Dr. Kumura studied the Zn content in brain tissue of schizophrenia and controls by polarography and confirmed that Zn level is significantly lower in the schizophrenic group than in other control cases.

According to these results, I tried to give oyster extract, which contains a large quantity of Zn, to several cases of hebephrenic patients. Most patients are getting better, namely affective flattening, poverty of speech and negativisum are gradually disappearing.

Dr. Nishigori gave oyster extract to ten cases of hebephrenic inpatients, tried quantitative analysis of Zn and Cu in serum and urine, and observed their clinical effect.

Recent studies confirmed that biochemical basis of paranoide form of schizophrenia seemed to be a variation of dopamine-β-hydroxylase and excess of Cu (Cu-hypermetallose), while hebephrenic form are Zn-deficiency (Zn-hypometallose), which is activator of carbonic anhydrase by cerebral glycolysis. In this meaning schizophrenias (paranoid and hebephrebic) are Cu- and Zn- dysmetallose.

Effects of an oyster extract on serum apoproteins were evaluated in 22 subjects with a mean age 35.6 years who participated in the Kaike Triathlon (swimming of 3km, cycling of 103.6km and a marathon of 42.195km) held in Tottori prefecture on July 25, 1984. Changes in serum apoproteins were studied before, during, and after the race.

The subjects ingested various doses of the oyster extract (12-20 tablets per day) from 3 weeks before the triathlon. On the day before the race, 12 tablets were administered after breakfast, lunch, and supper. In addition, on the day of the race, 12 tablets were given before starting as well as after swimming, cycling, and completing the race. Placebo was used in 11 subjects selected by a double-blind test. Blood was collected before breakfast (at rest) on the day before the race as well as after swim- ming, cycling and reaching the goal.

The group given the oyster extract showed 1) a higher apo A-I/A-II ratio, 2) a faster recovery from temporary decrease in apo A-I and apo A-II after exercise, 3) a greater decrease in apo C-II during competition, and 4) a greater decrease in apo E after swimming than the untreated control group.

Receptar is known as one of the receptive sites of the cell to obtain information from outside, frequently present in the plasma membrane but also in the nucleus ar cytoplasm.

As an abnormality of the receptor, familial hypercholestelemia (FH) is well known. The abnormality is found in the receptor for low density lipoprotein (LDL). Receptar also plays an important role in the liver, one of these being LDL-receptor, participating in the incorporation of LDL into the cell. In order to examine the relationship between liver function and receptor, experiments were conducted in rats to study the receptor abnormalities in the liver of animals with high LDL and HDL after maintenance with cholesterolrich diet. Compared to the isolated hepatacytes from control rats, a significant difference was not found in the receptor number and affinity in these experimental rats fed on cholesterol-rich diet.

Effect of selenium deficiency on hematological parameters of male Wistar rats was examined for the period of 3 months. Glutathione peroxidase (GSH-Px) in blood serum from rat fed Se-deficient diet (Se<0.01ppm) dropped to 36% of the selenium adequate rat at 2 weeks on the experimental diet, whereas GSH-Px in erythrocytes dropped to 2% after 3 months. Selenium contents in liver, kidney and heart also remarkably decreased in Se-deficient rats. Serum malondialdehyde level was found significantly increased in Se-deficient rats. However, no significant difference was observed in hematocrits and some enzyme activities: glutamate oxloacetate transaminase, glutamate pyruvate transaminase, lactic acid dehydrogenase, and creatine phosphokinase.

Although a few abnormal erythrocytes containing Heinz body and acanthocytes were observed in the blood from Se-deficient rats, no significant difference was detected in the ascorbic acid-induced hemolysis test and phospholipid composition of erythrocytes between Se-deficient and Se-adequate animals.

A glucosidase having specificity towards α-(1→2)-, α-(1→3)-, and α-(1→4)-D-glucosidic linkages, was solubilized from the rat small intestinal mucosa by papain treatment. The glucosidase was purfied in a highly homogeneous state by successive chromatographies on DEAE-Sephacel and Sepharcyl S-400 columns. The molecular weight of purified enzyme was 300,000, as estimated by Sephacryl S-400 gel filtration, and its isoelectric point was found to be 4.5.

The purified enzyme hydrolyzed kojibiose, nigerose, O-α-D-glucopyranosyl-(1→3)-O-α-D-glucopyranosy-(1→4)-O,α-D-glucopyranose ( elsinotriose ), maltose, maltotriose and amylose at a relative hydrolysis rate of 26, 18, 65, 100, 98, and 4, respectively. However, α, α-trehalose, panose, sucrose, isomaltose, maltitol and p-nitrophenyl α-D-glucopyranoside were not hydrolyzed.

We have found that elemental selenium is released enzymatically from selenocysteine. The deuterium isotope effect at the αposition is about 2.4. This indicates that the αhydrogen of selenocysteine is removed by a base at the active site. When the enzyme is incubated with L-selenocysteine in the absence of added pyridoxal 5'-phosphate,the activity decreases with prolonged incubation time. However, the activity is recovered by addition of pyridoxal 5'-phosphate. The spectrophotometric studies show that the inactivated enzyme is the apo form. The apo enzyme is activated by a combination of pyridoxamine 5'-phosphate and various α- keto acids. This regulatory mechanism is analogous to those of aspartate β-decarboxylase, arginine racemase, and kynureninase.

Although the essential roles of manganese ion (Mn) and requirement of its homeostasis have been studied in various biological systems, little is known about how Mn actually plays physiological roles. Our interests are focused on the determination of the redox passway of Mn through which Mn is transffered to an appropriate location for its function.

We determined the tissue and subcellular distributions of Mn (II), determined by ESR ( electron spin resonance), and of total Mn, determined by neutron activation analysis combined with chemical separation, differentiating two species of Mn in rats with and without MnCl₂-treatment.

In controls, total Mn content was high in the thyroid, hypophysis, adrenal, pancreas, liver and kidney, but Mn(II) contents of these tissues were low. In animals treated with MnCl₂, the total Mn content of all tissues increased, but the Mn(II) content remained low. In subcellular distribution, the total Mn content was high in nuclear and mitochondrial fractions of liver and kidney, and in the microsomal and supernatant fractions of the pancreas. The ratio of Mn(II) to total Mn was relatively high in microsomes of the liver and kidney of control rats, and in the nuclear fraction of pancreas of Mn-treated rats.

Partially purified liver nuclei and mitochondria were found to contain higher levels of Mn than the crude compartments, indicating that Mn is tightly bound in each cellular compartment.

The effect of iron, copper and zinc deficiency on the sulfur amino acids metabolism was investigated.

Animals were fed on iron-, copper- and zinc-depleted diets for 30 days. Serum iron and copper concentration of iron-deficient animals were decreased.

Serum copper and ceruloplasmin of copper-deficient animals were also decreased, but hepatic iron was extremely increased. The hepatic cysteine dioxygenase activities of iron-deficient animals was decreased compared to those of control animals.

However, the enzyme activities of copper- and zinc- deficient animals did not exhibit significant difference from that of control animals.

Urinary taurine concentrations of each metal deficient animals did not exhibit significant difference from that of respective control animals.

No significant difference was observed in the hepatic glutathione and cysteine content between the deficient animals and controls.

These results suggest that the depression of biosynthesis or the stimulation of degradation of cysteine dioxygenase is caused by iron deficiency.

The effect of tryptophan metabolites, anthranilic acid(A.A.) and 5-hydroxy anthranilic acid ( 5-OH-A.A.),on urinary bladder carcinogenesis in mice and rats treated with N-butyl-N-(4-hydroxybutyl)-Nitrosamine (BBN) were studied.

Experiment 1 : ICR strain male mice were given 0.05% BBN as an initiator for 8 weeks and following additions. To group 1, no chemical, to group 2 and 3, A.A. (0.5mg/mouse/day) or5-OH-A.A. for formar 10 weeks, to group 4 and 5, A.A. or 5-OH-A.A. for latter 10 weeks were added respectively.

Experiment 2: Fischer strain male rats were given 0.025% BBN as an initiator for 6 weeks and following additions. To group 1, no chemical, to group 2 and 3, A.A. (10mg/rat/day) or 5-OH-A.A.for 34 weeks after BBN, to group 4 or 5, A.A. or 5-OH-A.A.for 34 weeks without BBN.

In mice, sequential administration of A.A. or 5-OH-A.A. after BBN inhibit the urinary bladder carcinogenesis compared with simultaneous administration of these compounds with BBN.

In Rats, 5-OH-A.A. reduced the incidence and number of papilloma and carcinoma of the urinary bladder.

These result suggest the chemopreventive activity of 5・OH-A.A.against BBN induced urinary bladder cancer.

Four lactating Holstein cows were housed in the two independently controled climatic rooms. Although Mo concentration in milk decreased at 30°C, There were no significant differences in trace element concentration in milk between treatments. Negative retention of Zn, Se, and Mo at 26°C may be partly due to relatively high secretion in milk at 26°C. Since the ratio of secretion in milk to intake of Zn, Se, and Mo was extremely greater than that of Fe, Cu, Mn, and Co, more attention must be paid to Zn, Se, and Mo nutrition in relation to milk production. Results suggests that the Zn, Se, and Mo metabolism of lactating cows may be affected by heat stress.

In three experiments (Exp. 1, 2, 3), the 5-day balance study for zinc, copper and selenium were carried out in 16 healthy female subjects aged 20... 21 years. Menus were composed of ordinary foods and were typical of subjects’ usual dietary habits. Meat, seafood, and vegitable foodstuff was superior proportion of the experimental diet in Exp. 1, 2 and 3, respectively. The results obtained were as follows.

1. The zinc intake in Exp. 1, Exp. 2 and Exp. 3 was 7.6, 7.3 and 7.4mg/day, respec- tively. The zinc balance exhibited zero or slightly negative.

2. The copper intake in Exp. 1, Exp. 2 and Exp. 3 was 1.1, 1.1 and 1.8mg/day, respectively. Balance was markedly positive in Exp. 3 and was strongly influenced by the diet composition.

3. The selenium intake in Exp. 1, Exp. 2 and Exp. 3 was 83, 142 and 82-90μg/day, respectively. Selenium was excreted in urine equal to, or more in feces. Retention was markedly positive in Exp. 2, but absorption ratios were Exp. 3 > Exp. 2 > Exp. 1 in order.

4. Factorial analysis of variance was carried out on the effect of the diet composition. The result showed that absorption, the ratio of fecal excretion/intake and urinary excretion of copper were significantly affected by the diet composition, and fecal excretion, absorption, the ratio of fecal excretion/intake and retention of selenium were also affected by the diet composition, but these of zinc were unaffected by the diet composition.

The relationship between dietary taurine or sulfur amino acid intake and urinary taurine excretion in healthy college women was examined. The subjects were fed on ordinary diets which contain superior proportion of meats, fishes and vegitables as protein source in exp. 1, 2 and 3, respectively, for 5 days.

Dietary taurine content of exp. 2 was extremely higher than those of exp. 1 or exp. 3. Urinary taurine excretion of exp. 2 was also higher than those of other experiments. Significantly high correlation (r=0.8935) was observed between dietary. taurine intake and urinary taurine excretion. On the contrary, no significant correlation was observed between dietary sulfur amino acid intake and urinary taurine excretion.

These results suggest that urinary taurine is derived from dietary taurine rather than biosynthesis.

Endogenous concentrations of K vitamins(VKs) in human placenta and in paired samples of maternal and umbilical .cord plasma were detected and identified by high-performance liquid chromatography(HPLC) with fluorometric detection using post-column reduction.

Pylloquinone(K1) and menaquinones(K2: MK-4, 6, 7) were found in placentae and maternal plasma. K1 and MK-4 were found in umbilical cord plasma. (Table 1.)

The experimental subjects were (A) thirteen pregnant women with normal diet and (B) two pregnant women with diet addition of fermented soybeans (Natto) about 30g on alternate days for 1 month before delivery. As MK-7 is abundant in fermented soybeans, the placenta and maternal plasma of group (B) contained higher concentrations of MK-7 than group (A). But MK-7 was not found in umbilical cord plasma of any of the subjects.

These results may be helpful to elucidate the cause of neonatal hemorrhagic disease occuring a few days after birth which appears to be at least in part responsive to vitamin K therapy.

Various mineral levels in blood of inhabitants of a farm village and employees in a sugar factory (a branch of Japanese company) were determined. Calcium, phosphorus, potassium and iron levels. in plasma of inhabitants of the village were low as compared to the normal vlaues for Japanese. However, sodium and chloride levels in plasma and zinc level in whole blood of villagers were within the normal values for Japanese. In general, blood mineral levls in employees of the factory were higher than villagers, but lower than the normal values of Japanese. Correlations between these blood mineral levels and results of medical and biochemical examinations were analyzed using SAS program by computer and possible dicussions have been made. From these results, it is supposed that mineral nutrition of inhabitants in northeast Thailand, especially of villagers, are insufficient.

Various elements in serum were measured in adult women living in an agricultural area, Shiga Prefecture and their daily intake of nine minerals were calculated from the foodtables. presented in various literatures.

The average mineral concentration in serum were measured as follows: sodium, 140.9mEq/l; potassium, 4.3mEq/l; calcium, 4.5mEq/l; chlorine, 104.8mEq/l; phosphorous, 3.2mg/dl; iron, 102.7μg/dl.

The average daily intake of nine elements were estimated as follows: calcium, 563mg; phosphorous, 1102mg; iron, 10.6mg; sodium, 4595mg; potassium, 3211mg; magnesium, 241mg; zinc, 14.1mg; manganese, 3.2mg; copper, 1.4mg.

Serum sodium was positively correlated with serum chlorine and negatively correlated with calcium intake. Serum calcium was correlated with serum albumin, total protein, hemoglobin, hematocrit, MCH and MCV. Serum phosphorus was correlated with serum urea nitrogen. Serum iron was correlated with MCH, MCV, MCHC, hemoglobin and hematocrit. Each mineral intake. were closely correlated with one another. Among them, the correlation coefficient between manganese and copper was high, and the correlation coefficient between calcium and copper was not so high. Serum calcium was correlated with systolic blook pressure.

A study was made on the calcium concentration in the black deposits of human lungs which was considered to have been inhaled through air and then transferred into the body. The samples used for this study were taken exclusively from those living in Tokyo Metropolitan area with no history of lung disease.

The lung tissues were dissolved in alkaline solution and were prepared by multiple cycles of ultra-high speed centrifugation. The final residue was then washed using water and acetone and finally dried. The resulting black powder was analyzed, using a scanning electron microscope coupled with an X-ray microanalyzer for a general survey of the dust component.

In conclusion, an attempt was made to correlate the contents of several elements with age. Only Ca content presented a negative correlation as r = -0.56 (n = 72) and thus it was necessary to quantitatively analyzed the Ca content. Determination of Ca content was performed by neutron activation analysis. An agreement of negative correlation was shown in the non-smoker group as r = -0.57 (n = 14).

For comparison, Ca content in lung tissues including black deposits was deter- mined. Ca correlation in the non-smoker group (n = 6, males) was r = 0.46, while the correlation of the total number (n = 48) was r = 0.22.

The results suggested that Ca content of the negative correlation group was due to absorption of Ca which increased with age.