Since the Arizona group was first delineated by Edwards, West and Bruner (1947), many additional antigens and serotypes were recognized and members of the group have been found in a variety of pathological conditions of man and animals. Current knowledge of the biochemical, serological, and ecological characteristics of the group was summarized by Edwards, Fife, and Ramsey (1959) . Through studies covering several years the Arizona group has emerged as a distinct entity within the family Enterobacteriaceae, closely allied both biochemically and serologically to the genus Salmonella. Since the isolation of the original Arizona strains by Caldwell and Ryerson (1939) it has been known that organisms of this group occurred in reptiles but it was not until LeMinor, Fife, and Edwards (1958) recovered Arizona strains from 43% of 310 apparently normal snakes that their prevalence in reptiles was recognized. In the present paper eight newly recognized serotypes isolated from the feces of apparently normal snakes are described.

抄録全体を表示

Since Andrewes (1922) described “specific” and “nonspecific” flagellar antigens in several Salmonella types, the diphasic state has been recognized in hundreds of Salmonella serotypes and has been recognized also in the Arizona group (Edwards and West, 1945) . Similar variations have been found in the Escherichia freundii (Citobacter) group by Edwards (1946), in the Hafnia group by Deacon (1952), and in the Aerobacter cloacae (Cloaca) group by Sakazaki and Namioka (1960) .
Salmonella types which had complex phases and which gave rise to simpler types through loss variation were reported. Edwards and Bruner (1942) described S. salinatis (4, 12: d, e, h: d, e, n, z₁₅) which could be changed irreversibly to S. san diego (4, 12: e, h: e, n, z₁₅) while Edwards, Kauffmann and Huey (1957) found that S. montgomery (11: d, a: d, e, n, z₁₅) was changed to S. luciana (11: a: e, n, z₁₅) . Both of the changes resulted from the permanent loss of the common major antigenic constituent of phases 1 and 2 through cultivation in semisolid medium which contained d serum. Further, Edwards (1950) observed spontaneous irreversible segregation of e, h phases from more complex d, e, h phases. “Artificial” or induced phases often have been obtained by cultivation of salmonellae in homologous flagellar antisera. Thus, Kauffmann (1936) obtained j phases by cultivation of S, typhi in d serum and Edwards and Bruner (1939) and Bruner and Edwards (1941) obtained induced phases from S. abortus equi and S. paratyphi A. Such induced phases were reverted to naturally occurring antigens only with difficulty if, indeed, reversion was accomplished.
It is known that Salmonella types with similar H antigens yield similar induced phases. For example, salmonellae which contain antigen d tend to produce j phases when cultivated in homologous H antisera, and organisms which contained b antigens tend to yield z₃₃ phases (Edwards and Moran, 1946; Lederberg and Edwards, 1953) . These induced antigens function as phase 1 if the organism which yielded them originally was diphasic.
For instance, S. paratyphi B when cultivated in b and 1, 2 antisera yields a diphasic form having the H formula z₃₃: 1, 2. Further, such induced phases replace phase 1 of other types in transduction experiments (Lederberg and Edwards, unpublished data) . Thus, while various phases have been induced in enteric bacteria, these apparently were artifacts which occurred rarely, if at all, in nature and resulted from changes produced in the natural antigens. These changes were not additive changes but were substitutions and in no instance was the number of flagellar phases of the organisms increased. Diphasic organisms, after change of one of the phases to an induced antigen, still exhibited variation only between two points of reference, as did the original culture.
It was not until recently that Enterobacteriaceae which possessed three naturally occurring H antigens were found. Edwards and Fife (1960) recognized an Arizona serotype which had the antigenic formula 5, 29: 33: 21: 40. The three H phases, 33, 21, and 40, were known to occur naturally in other serotypes and were completely reversible at will in all directions. Later, Taylor and Lee (1960) recognized a culture of S. Worthington which had the antigenic formula 1, 13, 23: z: 1, w: z₄₃. The third phase was known to occur naturally in a number of cultures of S. senftenberg. The z₄₃ phase could be changed to z or 1, w at will and natural phase variation occurred between the z and 1, w components but neither of these was induced to revert to z₄₃ which was irretrievably lost.

抄録全体を表示

It has been attempted in this laboratory for the past years to isolate and passage herpes simplex virus by the chorioallantoic inoculation of embryonated eggs and pursue the changes in pathogenicities for various host animals occurring during the course of the passage. Among the pathogenicities examined were included those for baby mice intracerebrally or intraperitoneally inoculated, since Kilbourne and Horsfall (1951) stated that one-day old mice were equally susceptible to herpes virus inoculated by these two routes. A strain designated SK was studied most extensively.
A fact came to light thereby that the SK strain after passaged through eggs about 50 times was hardly lethal to baby mice when given by the intraperitoneal route, whereas the classical HF strain experiencing more than 450 egg passages still possessed a high infectivity to baby mice even by the peripheral inoculation. This paradoxical result stimulated a quantitative analysis of the infectivities to baby mice of SK strain in comparison with HF strain, and it was eventually disclosed that a mutant had appeared incidentally in an early egg passage of SK strain, which subsequently had replaced the parent type virus after several more passages. Details of those experiments are reported in the present communication.

抄録全体を表示

Hitherto Japanese B encephalitis (JBE) virus has been isolated in many instances from men, animals and mosquitoes and it has been thought probable that JBE virus is the only prevalent arbor virus in Japan. In the meantime, Ando et al. (1952) reported the isolation of a virus (Negishi virus) from the autopsied brain of a patient clinically diagnosed as JBE. By our recent studies, evidences have been accumulated which indicate that Negishi is a member of Group B virus bearing antigen closely related with Russian Spring Summer Encephalitis virus. However, neither virus isolation nor discovery of a human infection has been reported ever since 1949. More recently, Scherer (1958) reported that he could isolate a new Group A virus (Sagiyama virus) from mosquitoes in Saitama, Japan.
Taking those facts in account, it seems important to pursue the distribution of arbor viruses present in Japan over a period of years, hoping that such an investigation might give a clue to learn the ecology of arbor virus in nature. In a limited area, Gumma Prefecture, an investigation was started to gain detailed informations on the yearly appearance of arbor virus in arthropod. The present paper reveals the resuls obtained in the first year on the infection of mosquitoes in summer. The details of the isolation of 3 arbor viruses including a new one will be presented.

抄録全体を表示

One of the most prominent pathological changes evoked by the parenteral injection of Crotalidae venoms, including Habu venom, is hemorrhage (Taube et al., 1937; Fidler et al., 1940; Mitsuhashi et al., 1959; Kondo et al., 1960; Ohsaka et al., 1960 a, c) .
Hemorrhage is claimed to be due, at least in part, to the action of proteolytic enzymes (Houssay, 1930; Kellaway, 1939; Zeller, 1948; Porges, 1953; van Heyningen, 1954; Slotta, 1955; Kaiser et al., 1958; Maeno et al., 1958) . Recently Ohsaka et al. (1960 a, b) reported that zone electrophoretic fractionation of Habu venom revealed the presence of at least two hemorrhagic principles, designated as HR1 and HR2, both of which were associated with proteolytic activity on casein.
It is also well-known that Habu venom manifests lethal toxicity. It has been reported that the lethal toxicity of this venom was separable from such enzyme activities as phospholipase A, phosphodiesterase, 5'-nucleotidase and proteinase (with casein as substrate), which had been claimed to relate to the toxic actions (Ohsaka, 1958, 1960) . It is also interesting to show whether or not the principle responsible for the local effects also has the lethal toxicity. In our recent study it was indicated that one of the hemorrhagic principles (HR2) could be separated from at least the main part of lethal toxicity, while the other (HR1) associated with it (Ohsaka et al., 1960 a) .
In the present work, a study was undertaken on chromatographic fractionation of venom of Habu (Trimeresurus flavoviridis), a Crotalidae, in an attempt to obtain further informations about the relationships among hemorrhagic activity, lethal toxicity and proteolytic activity.

抄録全体を表示

The lack of knowledge concerning the metabolism and general physiology of adult hookworms is mainly due to difficulties in keeping them alive for prolonged observation outside the body of their host. In a previous paper (Komiya et al., 1956), it was shown that the adult of dog hookworm, A. caninum, can be kept alive for 6 weeks in the case of male and for 12 weeks in the case of female worms in dog serum. Since the filariform larvae of human hookworm, A. duodenale, were found to develop to the adult stage in the dog body experimentally (Yoshida et al., 1959), the following experiment was conducted to maintain this adult worm in vitro. On the other hand, in an attempt to know whether eggs laid in vitro could be developed to filariform larvae, the cultivation of the free-living stages was performed in the absence of living bacteria.

抄録全体を表示