Transduction experiments of tetracycline resistance were carried out on staphylococcus aureus of typing pattern 29/52/80/81, tetracycline (TC)-streptomycin (SM) -sensistive, penicillin (PC) -resistant, and phage type 29/52/52A/80/81 (TC-, SM-, PC-, sensistive) strains with the prophages obtained from strains of phage type 80/81 and phage type 52/80/81, which are TC-, SM-, PC-reristant.
It was observed that recipient strains aquired the TC resistance and also changed the typing pattern into that of the donors, losing the sensitivity to the typing phages 29, 29/52 and 29/ 52/52A. However, the transduction of SM-resistance did not accompanied a chnge of typing pattern.
These results suggest that the genetic factor governing the TC-resistance is closely linked to that of phage typing pattern 29.

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Sodium cinchophen was administered intraperitoneally in doses ranging from 20 to 50mg/ 100g body weight to adult male Holtmman rats. There occurred motor ataxia, somnolence, irritability, spasm, hyperglycemia, eosinopenia, hypothermia and acute hemorrhagic erosions in the glandular stomach. The dose of 40mg/100g body weight was found to be most useful for experimental study of gastric lesions.
Luminal, Dazepam, Chlordiazepoxide, Morphine, Hydroxyzine and Cyiproheptadine proved effective preventing the production of gastric lesions. Therefore, it is suggested that the middle typothalamic area plays a vital role in producing the cinchophen gastric lesions in the rat. The effects of these cetral neurotropic drugs on the gastric lesions did not necessarily correlated with those of the symptoms following cinchophen admiuistraton.

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Aspirin (Bayer) was orally administered in a dose of 20mg/100g body weifht to adult male Holtmzan rats. Hypothalamic lesions were bilaterally produced using a Krieg-Johnson stereotaxic instrument.
Subcutaneous injection of yeast caused hyperpyrexia in animals with anterior hypothalamic lesions, but not in posterior hypothalamic lesioned ones. Antipyretic effects and the development of acute hemorrhagic erosions in the glandular stomach following aspirin administration were suppressed by anterior hypothalamic lesions, but not by middle and posterior hypothalamic lesions.
The results suggest that the anterior hypothalamus is involved in the production of gastric erosions as well as antipyretic effect following oral administration of aspirin.

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In order ao elucidate the effects of cinchophen on hypothalamic electrical activity, conscious dogs were used in this experiments.
Intravenous administration of sodium cinchophen in a dose of 200mg/kg body weight caused hyperglycemia and evoked seizure discharge in record of the middle hypothalamus. Glucose also causes excitation of middle hypothalamic electrical activity similar to that induaed by cinchophen.
These findings strongly suggest that cinchophen acts through hyperglycemia directly upon the middle hypothalamus.

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Electron microscopic changes in the chief cell of the canine gastric gland after cinchophen administion were investigated, as compared with those after insulin administration.
The chief cells in the normal dog in response to cinchophen decreased in secretory granules, showing a picture of increasing excretion on the luminal surface.The Golgi cisternae were enlarged, indicating a marked production of secretory granules, and rough-surfaced endoplasmic reticula showed parallel disposition in contrast with distorted irregular arrangement seen after insulin administration.
In stalk-sectioned dogs, cinchophen in contrast with insulin failed to accelerate the secretion of the gastric chief cells : There were many secretory granules, their excretion was hardly discernible in the lumen of the cells, and the Golgi cisternae were scarcely enlarged, indicating very poor production of secretory granles, and rough-surfaced endoplasmic reticula were arranged in parallal and dispersed disposition.
In vagotomized dogs, secretory granules were found numerously after cinchophcn administraion, and their excretion was demonstrated to a considerable degree, whereas it was scarce after insulin administration. Enlargement of the Golgi cisternae and production of secretory granules were not remarkable, and rough-surfaced endoplasmic reticula showed a parallel disposition.
It is considered from these findings that cinchophen accelerates the secretion of the gastric chief cells, and that the acceleration is inhibited strongly by pituitary stalk section and also to a lesser degree by vagotomy.

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The effects of glucocorticoids on gastric secretion in the Heidenhain pouch dog after intramuscular single injection and intravenous infusion were studied for eight hours long.
Intramuscularly injected cortisone, hydrocortisone, triamcinolone and prednisolone caused a significant increase in pepsin secretion, showing a peak in a comparatively small dose, namely, 4 mg/kg of cortisone and its anti-inflammatory equivalent doses of the others. Somewhat similar pepsin secretion was observed following administration of paramethasone and betamethasone, but not by dexamethasone and methylprednisolone.
On the other hand, acid secretion following administration of the glucocorticoids increased considerably in proportion to the increase of their doses, except for cortisone which showed a peak secretion at 2 mg/kg.
In gastric secretion produced by these glucocorticoids, a common characteristic was recognized that acid and pepsin secretion reached the highest point six hours after they were given.
It was shown also by the continuous infusion method that more quantity of pepsin, and less of acid, was secreted with cortisone and hydrocortisoned than with dexamethasone and methylprednisolone.
The above mentioned differences in gastric secretion induced by the glucocorticoids seem to be originated from the differences of their molecular structures.

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Animal experiments have shown evidences in sepport of a hypothesis that some special strains of staphylococci are responsible for the development of staphylococcal infection of various tissues.
Firstly, of intravenously inoculated staphlococci obtained from surgical patients of purulent osteomyelitis, myositis, mastitis and furuncle, osteomyelitic staphylococci were recovered more numerously from bone tissues of young rabbits after 48 hours than those of other sources, and myositic staphylococci were similarly recovored from muscles after 6 hours. In contrast, other strains showed no special findings.
Secondly, young rabbits rendered susceptible to infection by pretreatment of Nitromine were intravenously injected with a small dose of staphylococci (10⁴/ml) of origins mentioned above.
The results have shown osteomyelitic and myositic staphylococci caused respectively osteomyelitis and myositis more frequently (64-65%) than other cocci.

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Loss of resistance to antibiotics during the culture at a higher temperature was studied on 18 multiply resistant strains of Staph. aureus. After incubation of 43°±0.5°C for 6 hours, 13 out of 18 strains lost their resistance to antibiotics. When the resistant Pattern of the 13 strains was analysed, penicillin resistance was lost in 10 out of 13 penicillin resistant strains, mercury resistance in 10 out of 10, erythromycin resistance in 1 out of 3, streptomycin resistance in 4 out of 11, and tetracycline resistance in 1 out of 12. Loss of resistances to penicillin, mercury and erythromycin were always associated with each other excepting one strain resistant to moderate amount of penicillin which lost resitance to mercury alone. Resistances to streptomycin, tetracycline and penicillin were lost independently. The growth rate was found to be different not only between incubating temperature of 43°C and 37°C, but also betweenresistant strains and their sensitive variants. These difference could lead to selection of the drug-sensitive variants as a result of growth at high temperature. Abscence of correlation between the occurance of the drug-sensitiv evariants and the growth rate at high temperature leaves open the question whether or not loss of resistance to antibiotics is induced by dilution of plasmid resulting from cell division.

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