著者
田波 洋 山田 喜紹 鈴木 聖 田崎 忠勝
出版者
日本ウイルス学会
雑誌
ウイルス (ISSN:00426857)
巻号頁・発行日
vol.19, no.4, pp.121-127, 1969
被引用文献数
1

Inhibitory effect of formycin and formycin B on the intracellular multiplication of goat pneumonitis agent (GP), a member of <i>Chlamydia psittaci</i>, was investigated. Drug was added to the nutrient fluid at two hours after inoculation to monolayers of either Earle's L or Yasumura's VERO cell lines. Infective units produced in cells cultivated in media which containd the antibiotic at varying dosage were assayed after an incubation period for 48 hours at 37&deg;C. The &ldquo;inclusion forming units&rdquo; were assayed by the &ldquo;infected cell count method&rdquo;.<br>The inhibitory action of both formycin and formycin B on GP-agent was far more effective in VERO cells than in L cells. The growth of the psittacosis agent in VERO cells was completely inhibited by formycin at a level of 1.4mcg per ml, whereas the drug did not inhibit the multiplication of the agent at the same concentration when L cells were chosen. The result may indicate that the psittacosis agent itself is resistant to these drugs, and that the inhibitory action is a result of some inhibitory effects of the host cell metabolism.<br>The inhibitory effect of formycin and formycin B on the psittacosis agent can be reversed to some extent by an addition of excessive purine or purine nucleoside to the nutrient media. Inosine, Na-inosinate, adenine or adenosine reversed the inhibitory effect of the two antibiotics. However, guanine and guanosine did not reverse the inhibitory effect. This may suggest that these drugs act as purine analogues, inhibiting certain essential metabolic pathway where adenosine may act an important role.
著者
田波 洋 山田 喜紹 田崎 忠勝
出版者
日本ウイルス学会
雑誌
ウイルス (ISSN:00426857)
巻号頁・発行日
vol.19, no.2, pp.70-76, 1969

The rate of adsorption of a psittacosis agent (Goat Pneumonitis agent, strain Nagano) by monolayers of Earle's L cell have been investigated. It has been shown experimentally that the rate at which psittacosis agent elementary bodies (0.35&mu; diamater) arrive at a surface of the cell monolayers can be accurately predicted from the theory of Brownian motion. Proportion of particles adsorbed by the monolayers during an adsorption time of t seconds, Y<sub>t</sub>, is given as Y<sub>t</sub>=1.51&times;10<sup>-3</sup>&radic;t.<br>There are good agreement between theoretical adsorption rate calculated from the above formula and experimentally obtained values within the experimental error. Therefore, we can estimate the number of total infective particles in the inoculum from the number of &ldquo;infected particles&rdquo; as shown by counting &ldquo;inclusion froming cells&rdquo; microscopically.<br>Adsorption of the psittacosis agent by L cell monolayers requires adequate concentration of cations. Optimum salt concentration for adsorption is approximately 10<sup>-2</sup> M. Divalent cations (Ca<sup>2+</sup>, Mg<sup>2+</sup> Mn<sup>2+</sup>) accelerate adsorption more effectively than univalent cations such as Na<sup>+</sup>, K<sup>+</sup> NH<sup>+</sup><sub>4</sub> etc. Optimum pH of the medium for psittacosis adsorption has been found to be 6.1; between 5.5 and 6.5 there is a slight decline in the efficiency of adsorption. At either sides of these pH values adsorption rate declines markedly.
著者
田波 洋 山田 喜紹 田崎 忠勝 村上 昇
出版者
長野県医学会
雑誌
信州医学雑誌 (ISSN:00373826)
巻号頁・発行日
vol.16, no.1, pp.101-108, 1967-02

信州医学雑誌 16(1): 101-108(1967)