Course of tuberculosis in patients among 9, 339 underground miners was observed from 1952 to 1959, 5 to 6 years for each patient, by film examination. Among 829 tuberculosis patients (8.9% of the observed), complete healing is seen in 2.1%, improvement in 10%, stationary cases in 37.4%, new attacks in 25.9%, and aggravation in 18.5%. Tuberculosis combined with silicosis shows markedly higher percentage in newly attacked cases and aggravated cases, while that without silicosis shows higher percentage in improved cases and stationary cases. Among persons in the pre-silicotic stage, relatively many newly attacked cases are found, while improved cases and aggravated cases are relatively few. Except tuberculosis combined with silicosis, kinds of work engaged during last 5 years show no significant difference in the incidence of new tuberculosis. Aggravated cases are found most in coal-face workers, relatively many in direct workers, and very few in coal collectors and indirect workers.

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Course of illness of 909 miners with silicosis and 143 silicotic miners covered by the Workmen's Compensation Law was observed from 1952 to 1959, 5 to 6 years for each patient. The results are as follows. If silicosis is graded as S₀, S₁, S₂, S₃ and S₄, with increasing severity, S_0-1, are found among workers in employment over 3 years below ground, S₁ and the above are among those in employment over 5 years underground, and most silicotic miners covered by the Law are found among those in employment of 7 to 9 years underground. According to the film examination, aggravated cases are found 7.1% in S_0-1, 22.5% in S₂, and 88.2% in S₃. Among these aggravated cases infiltration images are found in 97.6%. Socalled "unusually large nodulation" which has big significance in the aggravation of silicosis is found in 21.1% of S₁, 73.5% of S₂. The development of this nodulation shows almost no difference among workers of different kinds of work, except significutly low incidencer among coal collectors. However, aggravated cases are found among workers in decreasing degree in such order as: coal-face workers, indirect workers, and collectors. Cases of direct workers, infiltration are mostly of tuberculosis nature, and some of them are due to conglomeration of silicotic modules.

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Various work postures, with special reference to some of those still practised in rural districts in Japan, were studied by the usual EMG technique. The items include: postures assumed by the subjects with different heights of work table; heaving a weight (16 kg); carrying the weight by 5 different ways (using both hands together or one hand alone, carried on one shoulder, loaded on the back, and placed on the head) ; push and pull movents; forebend postures; motions involved in the acts of standing or sitting; and long continuous standing lasting for 5 hours. The degree of muscular activity was divided into 5 classes, viz. -…no electrical discharge, ±…just perceptively active, +…definitely active, ++…strongly active, and +++…intensely active. The chief results obtained are: 1. Corresponding to the known optimal sole-distance in heaving a heavy weight, where the energy requirement becomes minimum, there appears the least electrical activity among the leg muscles (see Table 1.). 2. The electrical activities of the muscles of the upper arm, the shoulder, the neck, and the back, indicate the most favourable table height to be the height of chair +1/6 the sitting height of the subject. Incidentally it has been shown that, when the forearm is held untouched to the table, the elbow joint is kept in position by M. brachialis and triceps brachii, and the biceps contributes very little or none at all (see Table 2). 3. In holding the weight in front of the body by both hands (with arms stretched), it requires a collaboration of the extensors of the forearms, as well as that of the flexors of the foreaaarms M. biceps brachii, deltoides, trapezius, supra-spinam, infraspinam, etc. When the elbows are bent somewhat, the activities of those muscles become considerably stronger (see Table 3). 4. If the weight is held sidewa!s dy one hand, some muscles inactive in Result 3, become definitely or strongly active on the unloaded side (notably M. pectralis major, obliquus abdominis externus and iliocostalis)-a display of counterbalancing action (see Table 4). 5. The use of 'tenbinbo', the Japanese version of the yoke and carried on one shoulder lengthways, lightens generally the muscular activities, compared with the same weight carried by one hand (see Table 4). 6. The load burdened on the back involves M. serratus dorsalis cranialis and quadriceps femoris into strong activities (see Table 5). Another feature of this is the increasing activity of the abdominal muscles as the load draws near the ship 7. The ancient custom of carrying load on the head, exclusively by women, is seen today in some remote rural corners, and it requires a long training. From the standpoint of mere muscular effort, this is found to be a most efficient way to carry load-in the sense that it uses mainly those muscles employed for standing, and that it burdens them not appreciably (see Table 6). 8. In pushing much lesser number of muscles is employed than in pulling (see Table 7). 9. The forebend posture is maintained by the muscles in the back. It is noteworthy that in the deep bending those become less active, and the abdominal obliquus are called into more activities. (see Fig. 2 and Table 8). 10. The motions involved in the acts of standing or sitting were analysed in terms of individual muscular activity. M. tibialis anterior, quadriceps femoris and glutaeus maximus are found to play the leading parts, while M. soleus, the most potent member among the lower extremity in maintaining standing posture, shows no activity (see Fig. 3). 11. In long continued standing, the behaviour of the soleus was studied. There are two kinds of discharge groups to be recognized in the muscle. One group indicates its mode of discharge interval at 0.13 sec.

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The influence of thioctic acid on fatigue was studied, using 41 male employees as the subjects. The flicker value, the threshold of patellar reflex and the reaction time to light were measured on 7 consecutive work days. The acid, 20 mg. a 〓y, was given to each of the nearly half of the subjects, while to the rest members placeboes were given. The means, caluculated from each set of observations, showed the following trends: 1. Flicker value. The acid was able to chek the daily lowering, which happens unavoidably under usual state, and there was on the whole a sign of lesser diurnal lowerings. 2. Patellar reflex. The threshold of the reflex showed similar effects like those seen in the flicker value. 3. Reaction time to light. The effects of the acid administration were very much obscure; yet one perceives an improvement of the reaction on the administered group. 4. For those subjects working the night shift the effects were remarkable. One may conclude from these observations that thioctic acid is effective to prevent fatigue, notably of the cumulative form.

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Studies on combination of erythrocytes with lead were made physically or chemically through hemolysis. Normal erythrocytes (A), erythrocytes bound with lead (B), and erythrocytes whose bound lead was removed with Ca-EDTA (C) were respectively hemolysed by the use of hypotonic saline solution, saponin, monoiodacetic acid, heat, and ultrasonic wave for comparative studies of their behavior to the hemolytic factors. (A) consisted of normal human erythrocytes rinsed with physiological saline solution and suspended in physiological saline solution at a rate of 2%; (B) was prepared by putting 5×10^-4 M of Pb into (A); and (C) was obtained by adding into (B) Ca-EDTA twice the equivalent of Pb. 1) Resistance to hypotonic saline solution was the highest in (A), followed in order by (C) and (B). 2) Resistance to saponin was the highest in (A), followed in order by (B) and (C). As a result of the removal of Pb, the recovery of resistance was not observed. 3) Erythrocytes bound with lead showed remarkably increased resistance to the hemolytic activity of monoiodacetic acid; and the resistance was lost following the removal of Pb. 4) Erythrocytes bound withlead as well as Pb-freed erythrocytes were more apt to undergo hemolysis by heat. 5) Hemolysis by ultrasonic wave showed no difference among three. The above findings suggest that Pb has the greatest effect upon the blood cell membrane. The results of the experiments with saponin and monoiodacetic acid indicate that the combination between Pb and blood cell membrane is a chemical phenomenon, suggesting the presence of a close relationship of Pb with lipoid and SH groups of protein in the cell menbrane. The combination velocity of Pb with erythrocytes is very high. However, the effect of the above binding does not appear so soon, and becomes increasingly noted with the lapse of time.

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By a previous author in our department, an experimental study had been made on the state of combination of lead in blood, applying the chelating action of Edathamil. In this study, the present author performed a similar experiment on organ-homogenates such as of liver, brain, lung, muscle, etc., in order to make overt the difference of combining affinity with lead by variable organs. The following conclusions were reached by the experiment. 1) In the liver of normal rabbits, there is such relation between the dose of added lead and the composition of Pb-EDTA as is expressed by an equation: y=4.70x^0.84, where y=dose of added, x=lead amount of Pb-EDTA. 2) The added lead into organ-homogenates of normal rabbits in vitro is combined with bone and liver more firmly than with brain or lung. 3) Lead in organs of rabbits with chronic lead poisoning is more stable to be combined, compared with lead in those with acute lead poisoning. 4) The different state of lead combination with variable organs or the difference of affinity with lead by organ is not only attributed to the different chemical property of water non-soluble protein, but might also be due to water soluble protein and other biological factors which are not detected by the present experiment.

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[in Japanese]

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Sodium monfluoroacetate has been introduced in Japan after the II War as an rodenticide against wild rats and some poisoning cases have been reported each year. Later monofluoroacetamide was put on the market as the insecticide for citrus orchards and its consumption is increasing every year. The present experiments were planned to find out effective antidotes against this economic poison. 1) LD₅₀ of monofluoroacetamide for rats was 3.2 mg/kg by intraperitoneal route, leading animals to death in three or four days. LD₉₀ was around 6.3 mg/kg. The intoxication dosis was fixed at 6mg/kg throughout these experiments and antidotes were given three times, at 1st, 4th and 7th hour following the administration of the poison. 2) The most effective antidote was acetamide or ethanol, both reducing the death rate down to two-third. Monoacetin, which is widely approved as the best remedy. was somewhat inferior to these. 3) Other drugs, which prolonged the surviving period, were procain amide, orotic acid (B₁₃), adrenochrome-semicarbazide, and sodium arsenate. 4) GABOB (γ-amino-β-hydroxy-butyric acid) and chloropromazine effectively inhibited the convulsion but no improvement of the surviving rate was observed. 5) The combined administration of acetamide, ethanol and procain amide showed the best result, reducing the death rate down to one third. The combination of monoacetin, ethanol and sodium arsenate was also excellent, reducing the rate down to one half. 6) The citric acid accumulation in tissues was also reduced when the drugs were effective on the surviving rate. This might be understood that these drugs had the good reason as antidotes from the standpoint of the biochemical mechanisms of poisoning proposed by R.A. Peters. 7) Fluorine contents in organs and tissues were also reduced in effective cases. 8) The mode of effective action of adrenochrome and sodium arsenate is not clear at present. From the results above mentioned, it may be concluded that the best method of treatment will be the combination of ethanol with acetamide or monoacetin as acetate-donor, procain amide against the ventricular fibrillation, and orotic acid (B₁₃) for detoxication.

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