岡山医学会 Acta Medica Okayama 0030-1558 86 1-2 1974 児島湾の水質調査について(1) 23 28 EN Yasuhiro Kanemasa Takeshi Katayama Kazuya Akatsuka Hiroshi Hara Jutaro Tawara The chemical and microbiological investigations of Kojima Bay were carried out for the purpose of clarifying the water pollution. The results and some discussions are summarizedd as follows. 1. Kojima Bay had been progressively polluted with organic compounds and inorganic nitorogen, but the situation of this bay has been improving for some years except transparency in the whole area and pollution by coli form group in the bay bottom. 2. The salinity of the surface water in Kojima Bay was conciderably low, half as much as that of the sea water. Then, Kojima Bay is in a suitable condition for the outbreak of red tides in a point of salinity. 3. The pollution load by the industrial and munincipal wast water drained into the bay is extremely too large for the volume of this bay. 4. In due considerations of the geographical condition and the pollution load, the waste water should be treated in closed system. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 85 11-12 1973 児島湖の水質調査 601 605 EN Yasuhiro Kanemasa Takeshi Katayama Akinobu Okabe Yasumi Mori For the purpose of clarifying the water pollution of Lake Kojima, two samples of water were collected and analyzed from each surface and bottom at 7 different parts in the lake. The results are summarized as follows. 1. The lake has been remarkably tainted with organic substances as grasped from the result of COD. 2. There were nutritious salts in high concentration, consequently accelerating a eutrophication. Especially, the bottom water contained a large quantity of NH(4+) because of anaerobic decomposition. 3. In summer, an overgrowth of phytoplankton was observed and pH of surface water shifted to respectable alkaline in consequence. 4. The conversion of Lake Kojima to fresh-water had not been succeeded. For the preventive measure of eutrophication, the exhaust of nitrogen and phosphorus compounds should be controled. If not so, the condition of Lake Kojima will turn to inappropriate to fish subsistence. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 85 9-10 1973 細菌細胞中のカチオン測定法に関する検討 481 486 EN Takeshi Katayama Ken-ichi Tomochika Chieko Takatsu Yasuhiro Kanemasa Jutaro Tawara The precise mensuration of the intracellular cation content is very significant from the biological point of view. When a salt concentration is medium is higher than in bacterial cells, it is very difficult to measure the intracellular cation content because of extracellular high contamination. In such a case, there is no other way except repeated washing for elimination of the outer contaminants. With the repeated washing method, authors attempted to measure accurately the intracellular cation content of Staph. aureus 209 P, cultivated in the medium of the various degrees of salt concentration, by flame photometory and atomic absorption spectrophotometory. The results were as follows. 1. When univalent cation concentration in cells is lower than in medium, it is necessary to wash the cells several times. The washing effect on extracellular contaminants could agree with the theoretical equation of washing that the contaminant decreased exponentially. The successive decrease of assay values by an easy grade must show a leakage of the intracellular Na. The reflective point could be considerated to show the Na content. 2. As in general potassium concentration in cells is higher than in medium, the accurate value was decided by extrapolation of the linear analytical quantity vs. washing time to zero time. 3. In spite of the extreme variation of sodium salt concentration in culture medium, the univalent cation content in Staph. aureus 209 P had hardly any shifts. 4. Bivalent cations, Mg and Ca, were not affected by the washing. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 87 3-4 1975 ブドウ球菌の耐塩機構に関する物性論的研究 259 270 EN Takeshi Katayama To clarify salt-resistant mechanism of Staphylococcus aureus from the standpoint of the passive transport, attempts were made to establish the experimental system of artificial model membrane, liposome, and to measure permeability of Na(+) to it. The liposomes were prepared from phospholipids of S. aureus cultivated in normal and 10% NaCl media and NaCl-sensitive mutants. 1. In physiological conditions, it is possible to form the stable liposome comprised of phospholipids or total lipids of S. aureus. The preparation methods give a remarkable difference in the shape of vesicles. In the case of particles produced by hand or mechanical shaking, the diversities in the size and shape of individual particles can be observed. Sonicator-prepared liposomes are small and homogeneous of particle size, and consist of unilamella rather than multilamella. 2. Salt concentration affects liposome formation. Cardiolipin containing abundant branchedfatty acid form stable vesicles even in a high concentration of NaCl solution. 3. The liposome prepared from phospholipids of 10% NaCl S. aureus suppresses more markedly in the rate of Na(+) diffusion than that of normal S. aureus. The experiments on the liposomes prepared from fractionated individual phospholipids indicate that cardiolipin containing branchedfatty acid contributes to salt-resistance of S. aureus as a barrier. 4. From optical measurements, it has been elucidated that the liposome of phospholipids prepared from S. aureus acts as an ideal osmometer, and non-electrolyte, glycerol, shows a similar behavior to Na(+) in permeability. No potential conflict of interest relevant to this article was reported.