Various organophosphorus compounds are widely used in the world. Each organophosphorus compound has some differences in toxic symptoms, inhibition of ChE (cholinesterase) and the efficacy of PAM (2-pyridine aldoxime methiodide). This paper reports on the effects of three organophosphorus compounds (1/2 LD₅₀, p. o.) and PAM on ChE activity in rat tissues including the relation to toxic signs. The results were as follows:
1. Toxic signs appeared in the respiratory function of rats immediately after administration of Dichlorvos, and these signs disappeared rapidly. But in the case of rats administered Fenitrothion or Pyridaphenthion, serious toxic signs such as salivation, dyspnoea, lacrimation and tremors caused decreased body weight and rise of hematcrit value, and these signs continued for several days.
2. ChE activity in rat tissues administered organophosphorus compounds spontaneously recovered further after the toxic signs disappeared. But there was a clear relation between the inhibition levels of tissue ChE and the appearance of toxic signs in rats administered three organophosphorus compounds. With special reference to the correlation between salivation and the inhibition level of ChE activity in salivary glands, serious salivary secretion was observed in rats where ChE activity in the glands was inhibited severely by administration of Fenitrothion or Pyridaphenthion. It was clear that salivary secretion was induced by organophosphorus compounds when the activity of ChE in salivary glands was inhibited by more than 50% of normal activity.
3. The half-time (r_1/2) for spontaneous recovery of tissues' ChE activity in rats following poisoning with organophosphorus compounds was different by tissues. But the r_1/2 for recovery of serum and liver ChE activity was the same as the approximate 20h for three organophosphorus compounds, and those were shorter than other tissues' ChE. The r_1/2 for recovery of erythrocytes ChE was longest in tissues, particularly those of rats treated with Fenitrothion was as long as 410h.
4. As expected, atropine was unable entirely to reactivate tissue ChE activity inhibited by three organophosphorus compounds. The antidote PAM was capable of reactivating ChE activity in only serum and erythrocytes of rats administered Pyridaphenthion, but it couldn't reactivate ChE activity in brain, liver, kidneys, lung and salivary glands for pyridaphenthion, nor ChE activity in any tissues for Dichlorvos and Fenitrothion.
Therefore, it was clear that each ChE in rat tissues has many differences in the speed of spontaneous recovery and the reactivating effect of PAM following poisoning with organophosphorus compounds. The qualitative differences of ChE by each tissue will be made clear in the future by a study on ChE isoenzyme of rat tissues.

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This paper deals with studies on the method of selenium determination in biological samples and several fundamental experiments using the rapid semi-automized electrothermal atomisation atomic absorption spectro-photometric procedure.
Samples were digested with a mixture of nitric acid and perchloric acid, then selenium was determined by hydrogen evolution electrothermal atomic absorption method. Coexistence of high concentrations of Fe, As, Ni and Cu interferes with selenium determination. However, these interferences could be negligible in the case of determination of biological samples.
The sensitivity of this method is sufficient for application to the determination of selenium in biological samples.

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417 strains of Proteus mirabilis were isolated and studied for their resistance to three metals and four drugs. Distribution patterns of susceptibility clearly revealed two peaks of resistance to Hg, Cd, and As, but only one peak in the case of Pb. The frequencies of resistance to Hg, Cd, As, SM, TC, CP, and KM were 28.8, 95.7, 57.1, 50.1, 41.7, 32.1, and 29.5%, respectively. And the frequency of Hg resistance in P. mirabilis isolates was 58.3% during 1975 to 1977 and decreased to 16.8% in 1979 to 1982.
Among these isolates, 120 Hg-resistant strains were tested for their ability to transfer this resistance to mercury and drug-sensitive recipients of E. coli K12-ML1410-Nx and E. coli JE17-Rif. 107 of these, or 89%, demonstrated Hg-resistant transferable R plasmids.
Further, using radioactive ²⁰³Hg²⁺, we tested the ability of strains containing these plasmids to volatilize mercury. It was found that all of these strains have inducible ability to volatilize to inorganic mercury.

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This paper analyzes the trend of mortality from cirrhosis of the liver in Japan based upon Vital Statistics published between 1955 and 1979.
The shape of the age-specific mortality curve in number for male cirrhosis of the liver was shown to form a unimodal with maximum frequency around the 60-64 age group in the period 1955-59. Recently, however, younger deaths from cirrhosis have gradually increased and in the period 1975-79 its shape dramatically changed to a bimodal peak: the younger peak representing the 45-49 age group and the older the 60-64 age group. Deaths occurred in this younger age peak were shown to be contributed mainly by the cohort born in 1930-40 by applying the Weibull model and Multiplicative model. No such peculiar pattern was found in the age-specific mortality curve for female cirrhosis.
Furthermore an analysis of the clinical records of the Tokyo Metropolitan Komagome Hospital during 1975-1983 showed that many of the male patients who died from cirrhosis of the liver were alcoholic cirrhotics and the shape of the age-specific mortality curve in number also had a similar bimodal curve.
Consequently, it was suggested that the increasing trend of mortality from cirrhosis of the liver in recent years could be explained by two main factors: the effect of the male cohort born in 1930-40 and the effect of the consumption of alcoholic beverages. As to this cohort characteristics, life environmental factors, such as experience of World War II, insufficient nutrition and labour conditions, were considered to be important determining factors.

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The present study re-evaluates five funcional tests for measuring fatigue. These include tapping, colour calling, knee reflex, flicker and two-point discrimination tests. Eight faculty staff and technicians of a medical school were tested in the morning of each working day over a period of four years.
A period of accustomization to the tests was observed. In the first 5 to 10 days of testing scores fluctuated widely; thereafter most test scores remained relatively constant for each individual. However the tapping and colour calling tests required up to one and a half years to become reproducible.
Among subjects there were large variations in the result of the knee reflex and two-point discrimination tests, and relatively small variations for the tapping and flicker tests. In all five tests however intra-personal were significantly less than inter-personal variations.
No age-trend was observed among the subjects, whose ages ranged only from 20 to 40 years.
The female subjects performed the colour calling test faster than the males.
No seasonal pattern was observed. The only weekly pattern was a significantly greater coefficient of variation of the flicker test scores for Thursday and Friday. The menstrual cycle did not appear to affect any of the fatigue test performances.
For individuals accustomed to these tests difference between pre- and post-stress performance may be a reproducible measure of fatigue.

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Inhibitory action of some chemicals and antiserum on the enhanced lethal toxicity due to the combination of thermostable direct hemolysin produced by Vibrio parahaemolyticus and staphylococcal enterotoxin was investigated with animal experiments.
No inhibition was found with calcium chloride, epinephrin, dopamine, β-methasone and theophyllin administrated to rats either singly or by mixture.
However, the lethal toxicity was repressed with antiserum for the Vibrio thermostable direct hemolysin after injection of the toxins; one rat in six survived with treatment with 0.5mg/kg of the antiserum and three out of six were left alive with 1mg/kg administered treatment.
Furthermore, the effect of antiserum was increased by adding theophyllin and no rat died in the case treated with 1mg/kg of antiserum and 40mg/kg of theophyllin.

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Eighty 21-day old Wistar male rats were divided into four groups; each group was given drinking water containing 0 (control), 1, 5 or 10ppm of cadmium daily. After four weeks' administration, a torsional strength test of the long bones, a hematological test and a cadmium determination of the tibia, kidney and liver were carried out.
In the 10ppm group, both the femur and the humerus showed a 10 per cent decrease in strength as compared with the control group. Cadmium concentrations determined by atomic absorption spectroscopy were 13.5±2.6μg/g dry weight of the liver, 15.0±2.3μg/g dry weight of the kindney, 146.1±26.3ng/g dry weight of the tibia and 66.2±6.9ng/g dry weight of the diaphysis of the tibia. Anemia, decrease in serum iron and increase in serum phosphrus were also found in the 10ppm group.
In the 5ppm group, the torsional strength of the bones was not statistically different from that of the control group, but there was anemia and decrease in serum iron.
There was no significant difference in the bone strength and the results of the hematological test between the 1ppm group and the control group.

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Biochemical effects in mice and cytotoxicity in a cultured cell line of a poisonous mushroom extract, Amanita abrupta were studied. The aqueous extract of the mushroom was injected intraperitoneally into male SPF ddy mice and the changes of components and enzymes in blood, liver and urine were determined. The cytotoxicity of the mushroom extract was also studied in terms of the effect on the colony formation of KB cells.
Biochemical changes were observed after a latent period of 6h after the injection; blood glucose and liver glycogen decreased to 60% and 10% of the control levels, respectively. Serum glutamate-oxalacetate transaminase (GOT) and blood urea nitrogen (BUN) increased to 3-fold that of the control levels at 12-15h after the injection and remained at these high levels for 24h.
Urinary parameters were significantly affected by the mushroom extract.
The mushroom extract showed a marked inhibitory effect on the plating efficiency of KB cells.

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A new scheme for species-classification of staphylococci was applied to 124 strains of airborne staphylococci (A. S.) isolated from the air in hospital wards. For comparison, 204 strains of A. S. dispersed from healthy subjects and 521 strains of staphylococci isolated from their skin were also classified. In addition, both strains of A. S. in hospital wards and from the healthy subjects were tested for susceptibility to 11 major antibiotics (penicillin G, methicillin, cloxacillin, ampicillin, cephaloridine, erythromycin, chloramphenicol, streptomycin, tetracycline, kanamycin and gentamycin).
The results obtained were as follows:
1. One of the 124 strains of A. S. from the hospital wards was identified as Staphylococcus aureus (S. aureus). The remaining 123 strains of coagulase-negative staphylococci (CNS) were classified into S. epidermidis (35.5%), S. haemolyticus (11.3%) and other species, except for 41 strains (33.1%) which were not classified. Most of the staphylococcal strains isolated from the healthy human skin were identified as S. epidermidis (82.0%). On the other hand, a large number of unclassifiable strains (76.5%) were observed in A. S. from the healthy subjects.
2. The airborne CNS strains from the hospital wards showed marked differences in minimal inhibitory concentration (MIC) for all antibiotics tested when compared to those from the healthy subjects. Particularly, half of them were resistant to penicillin G, methicillin, ampicillin and kanamycin. Similarly, the rate of airborne CNS strains in hospital wards was much higher for multi-drug resistance than those from the healthy subjects.
The results suggest that some airborne CNS in hospital wards may act as opportunistic pathogens.

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