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Normal oligodendrocytes were separated from 7-day-old mouse (BALB/c) brains by the Percoll gradient method. Immunohistochemical staining with an anti-galactocerebroside serum revealed that about 85% of the separated cells were oligodendrocytes. The oligodendrocytes were transplanted into the corpus striatum of 4-week-old shiverer mutant mice which are characterized by the lack of myelin basic protein (MBP). Myelination by the implanted oligodendrocytes was investigated immunohistochemically and electron microscopically 6 weeks after the operation. Certain areas in the corpus striatum were intensely stained with antiserum to MBP. Electron microscopic examination showed that some axons were surrounded by normal type myelin sheaths with major dense lines. These results clearly indicate that matured oligodendrocytes are able to survive and myelinate the host axons even in the adult brain.

The immunological activity of eel calcitonin was more persistent than that of porcine and human calcitonin when incubated in vitro with rabbit serum, human serum, liver homogenate or kidney homogenate, respectively. Both eel and human calcitonin were more stable than porcine calcitonin when injected iv into rabbits.

A method for specific removal of [32P]orthophosphate (Pi) as phosphomolybdate-triethylamine complex was slightly modified by repeating the Pi precipitation procedures in the presence of unlabeled Pi, which resulted in a complete removal of 32Pi (greater than 99.98%). Using this modified method, we determined 32P incorporation into acid-soluble compounds in order to evaluate the ATP-forming ability of Bacillus megaterium spores at the very early stage of germination. Addition of fructose as a substrate started the 32P incorporation later than a few min after triggering germination. This delay of a few min was well coincident with the onset of 3-phosphoglycerate (3PGA) breakdown, indicating that fructose metabolism and the accompanying aerobic ATP formation were initiated only after fructose phosphorylation by the ATP derived from anaerobic breakdown of endogenous 3PGA. In contrast, addition of glucose started incorporation of 32P into acid-soluble compounds immediately after germination. In the latter case, NADH generated by glucose oxidation to gluconate (catalyzed by glucose dehydrogenase) might serve as an initial ATP source without depending on 3PGA breakdown and glucose metabolism via the Embden-Meyerhof pathway.

An effect of a combination of ampicillin (ABPC) and dicloxacillin (MDIPC) on penicillins and cephalosporin-susceptible E. coli was determined. Minimum inhibitory concentrations of the combined drug were as same as that of ABPC, but bacterial growth was inhibited by the combined drug stronger than ABPC, low activity of beta-lactamase was detected in sonicated E. coli 0.225 cells, and this activity was inhibited by relatively low concentration of MDIPC. We considered that a weak synergism of the combined drug might attribute to the inhibition of the beta-lactamase activity by MDIPC.

The effects of subcultured astrocytes on the proliferation of neuronal precursor cells (neuroblasts) from rat embryonic cerebral hemispheres were examined. The survivability of neurons and the neurite outgrowth were significantly enhanced by the subcultured astrocytes compared to those of neurons plated on poly-L-lysine-coated coverslips. The incorporation of [3H]thymidine into neuroblasts was remarkably suppressed by the subcultured astrocytes indicating that the astrocytes inhibit the proliferation of neuroblasts. These results suggest that astrocytes enhance the maturation of neuroblasts possibly via either cell-cell contact or trophic substances.

Stereoisomeric alanylalanine (Ala-Ala) derivatives were examined for their effects on germination of Bacillus thiaminolyticus spores. L-Ala-L-Ala and L-Ala-glycine were effective in inducing germination, and their activities were completely inhibited by D-Ala. L-Ala-D-Ala and glycine-D-Ala competitively prevented L-Ala-induced germination. Sarcosine- or beta-Ala-containing L-alanyldipeptides and eight kinds of alanyltripeptides did not show any detectable effect on germinability or any inhibitory effect. No detectable amounts of Ala were found in germination exudates when alanylpeptides were incubated with spores. The ability of these peptides to induce or inhibit germination depends on their steric conformation and a certain distance between the primary amino group and the free carboxyl groups. Involvement of L-Ala dehydrogenase in the initiation of germination is unlikely because L-Ala-L-Ala was not a substrate and L-Ala-D-Ala was not an effective inhibitor of enzyme activity.

Cyanocuprol is markedly effective in tuberculosis, and we believe that it will play an important part in clinical medicine. It may be used more generally than tuberculin. The amount of the dose is closely related to the reaction and the final results. It should be determined for each patient after a careful examination of his symptoms. The maximum dose of 8.5 cc. should in no case be exceeded. The shortest interval between injections should be 2 weeks. If the drug is given after a shorter interval, no improvement is observed and the effects are sometimes dangerous. In order to obtain the best results the patient should be placed under conditions of complete physical and mental rest after the injection; this applies even to light cases. Care should also be taken to secure rest for the lesion. During the period of the treatment irritants to the lesion, such as potassium iodide or tuberculin, should be avoided; apricot juice, guaiacol and its derivatives, and iodol are contraindicated. No marked idiosyncrasy has been noted and no accumulative effects have been observed.

1. Microscopical examination of sputum that has been washed with isotonic salt solution indicates its source. Sputum from above the vocal cords contains polygonal flat epithelial cells and numerous species of non-pathogenic microorganisms. Sputum from below the cords is clear of saprophytes, although it sometimes contains bronchoalveolar cuboidal cells. 2. The source of the sputum can be determined by the erythrocytes and the bacilli that are contained in it, and the site of the lesion can also be ascertained. 3. In every instance I found erythrocytes in the pulmonary sputum after severe pulmonary hemorrhage. 4. Six of the cases of laryngeal affection referred to in the presentpaper had had no subjective symptoms, but microscopical examination showed tubercle bacilli in the laryngeal sputum. All the six cases were examined by Dr. Tanaka and were found to have tuberculous lesions in the larynx. In the laryngeal sputum of most cases of laryngeal tuberculosis with symptoms, tubercle bacilli have been frequently demonstrated, while in some cases contaminated laryngeal sputum was obtained only after a long series of examinations. 5. Microscopical examination of the sputum plays a significant part in the diagnosis of tuberculosis.