Glucose 6-phosphate isomerase (GPI) (EC 220.127.116.11.) from Actinomyces viscosus RF-7 was partially purified approximately 60-fold from very small amounts of sample (2.0 g wet weight of cells) by a combination of diethylamino-cellulose and Sephadex G-150 column chromatography. The GPI was stable at 4°C, but was relatively labile at 37°C. With the addition of glycerol, however, the partially purified enzyme became considerably stable at-20°C. Furthermore, no loss of activity was observed over a 4-month period at 4°C or-20°C under the above condition.
The effects of sulpiride (25 μg in 0.5 μl) injected into either the dorsal striatum or nucleus accumbens on licking, gnawing and locomotion induced in rats by either methamphetamine (10 mg/kg) or apomorphine (2 and 4 mg/kg) were investigated. Sulpiride injected into the dorsal striatum enhanced methamphetamine-induced gnawing but not that induced by apomorphine, a directly-acting dopamine agonist. These results suggest that enhancement of the effect of methamphetamine may be due to the inhibition by sulpiride of the striatonigral negative feedback mechanisms controlling dopamine release. Sulpiride injected into the nucleus accumbens blocked methamphetamine-induced gnawing without affecting the effects of apomorphine. Antagonism of the effects of methamphetamine by blockade of dopamine receptors within the nucleus accumbens has not previously been reported and cannot be easily explained on the basis of present knowledge. Hyperlocomotion produced by methamphetamine (10 mg/kg) was significantly reduced by injection of sulpiride into the nucleus accumbens but not into the dorsal striatum. Injection of sulpiride into the nucleus accumbens more markedly reduced hyperlocomotion produced by apomorphine (2 and 4 mg/kg) than did injection of sulpiride into the dorsal striatum. These results support the hypothesis that the nucleus accumbens more effectively generates dopamine-mediated locomotion via D2 receptors than the striatum.
For endodontics, it is necessary to determine the working length of the root canal accurately. Recently, the electronic method for measuring root canal length developed by SUNADA has become widely used in Japan. However, when an electro-conductive substance such as blood is present in the root canal, measuring errors tend to occur, causing clinical problems. We examined the present electronic method for measuring root canal length, and, from basic experiments, found that the measuring principle of this method depended on a simple electronic phenomenon. We were then successful in developing the Endotape method, which made it possible to measure the root canal length accurately even when electro-conductive substances such as blood and pus were present in the root canal. Also, the Endo-cater, an apparatus for measuring the root canal length, using applied high frequency, was shown to be greatly improved in its manipulability and measuring accuracy. These modalities were then applied clinically and good results were obtained.
In the previous study, a statistically significant positive correlation between natural background radiation exposure rates and crude (non-age-adjusted) cancer mortality rates was observed in 46 Japanese prefectures over the period from 1968 until 1978. In the present investigation, however, the significance of this correlation mostly disappeared through age adjustment with only the two exceptions of female stomach and uterine cancers. Age adjusted male esophagus cancer mortality rate still showed a significant negative correlation. Female esophagus and pancreas cancers became negatively correlated with exposure rate through age adjustment. It was suggested that natural radiation levels are positively correlated with prefectural population component ratios older than 40, 50 and 65 years, which was considered to be one of the causes of apparent correlation between exposure rates and crude cancer mortality rates.
The authors conducted analysis of contour repeatability of lower jaw functional impressions made according to Herbst's method. Functional impressions were made for fifteen edentulous patients (three for each of the patients) according to this method. The impressions were made of Adheseal resin-wax compound, Xantopren silicone elastomer or Ash's zinc oxide eugenol paste. The working models were cut along previously designated lines using an accurate circular saw designed for this purpose. Cut lines were made so that they were identical in all of the models for a given patient and comparable (in the greatest practically possible approximation) for different patients. The depth and width of the vestibular sulcus as well as the lingual sulcus were measured exactly to within 0.001 mm on the cross-sections of the models using a microscope. The data for 3, 780 measurements were then statistically evaluated. On the basis of reproducibility analysis of the vestibular sulcus and lingual sulcus, an almost identical usefulness for all examined impression materials forming functional profile impressions according to Herbst was found. It was determined that this method employs functional tests which facilitate the repeated projection of chosen arrangements of tissues adjacent to the borders of a complete lower denture.