ムギ萎縮病ウイルスの土壤伝播のメカニズムを明らかにするために, WYMVおよびBYMVの2種のウイルスの汚染土壤を用いて実験を行なつた. 本報において, 現在までに得られた結果を報告すると共に, これに基いてこれらウイルスの土壤伝播機作に関する1つの見解を述べた.
罹病植物体全部を磨砕し埋没した土壤は, 初年度および次年度には全く病原性を示さなかつたが, 3年目に至りいずれの罹病植物埋没土壌においてもわずかながら感染個体を認めた.
水に浸漬した病土を, Stokesの公式に基き, あるいはASK淘汰器により, 数種の大きさの土壤粒子のfractionに分けてそれらの病原性を調べた結果, 最初の2年間は‘10-50μ’附近の大きさの粒子から成る土壌のみに病原性を認めたが, 3年目には‘<1μ’および‘<4μ’fractionにおいてもかなりの感染個体を認めた.
上記の結果のうち, ‘<1μ’あるいは‘<4μ’fraction中のそれぞれの土壤粒子の量は, 分別操作の方法の相違のために, 他のfractionにおける粒子の量に比し極めて少ないことを考慮して, 採取した微細粒子の懸濁液を遠心分離 (4000rpm., 15-20分) により濃縮した. その結果‘<2μ’fraction (国際土壤学会法による粘土部分) の土壤粒子が特に強い病原性を有することを知つた. この実験における感染個体は, これら粘土粒子の集積に播種された場合のみならず, この粘土粒子による摩擦接種試験からも得られた. なお, 分離濃縮した粘土部分の粒子および‘>2μ’粒子の数部分を取り, 水で稀釈してたびたび検鏡したが, 前者において特記すべき頻度であらわれる細菌または糸状菌を認めなかつた. さらにまた, これらの粘士部分の粒子中には, 線虫類を全く認めなかつた.
本報に述べた実験結果と, 筆者のこれまでの実験から得た知識とを併せ考え, 従来のムギ萎縮病ウイルスおよびその他の土壤伝播生ウイルスに関する研究結果を種々検討し, さらに土壌学的見地からの考察をも試みた結果, 筆者は次のような見解に達した. すなわち, 少なくともムギ萎縮病ウイルスの土壌伝播のメカニズムを説明するためには, 何ら特定の微生物的媒介者を必要とせず, 蛋白質を吸着し且つ保護すると考えられる粘土部分 (‘<2μ’particle fraction, 無機および有機コロイドを含む) の粒子が, ウイルスを吸着してcarrzerの役割を果しているものと考える.

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In the past, remarkable difference was encountered in the routine potency tests of the Japanese encephalitis vaccines of two different strains of virus, G-1 and Nakayama, challenged with Nakayama strain. Such result gave us a suggestion of strain difference which might exist in producing immunity in mice.
In order to give answer to such question, the vaccines were prepared with 2 strains, Nakayama and G-1, respectively. Both viruses were identified serologically as Japanese encephalitis viruses. Group of mice were immunized with 2 vaccines, and after the vaccination, cross challenge test was accomplished with both strains on the one hand and on the other, neutralization, complement-fixation and hemagglutination inhibition tests were carried out on sera collected from mice at 2 weeks after the initial vaccination.
As the results, protection index obtained in Nakayama-immunized mice challenged with the heterologous strain at 2 weeks was found to be lower than that obtained by the challenge with homologous one. In case of G-1-immunized mice, the protection index was found very low when challenged either with the homologous strain or with the heterologous one. However, no significant difference was recognized in term of antibody titer between the mice immunized with both strain vaccines.

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It was assumed that the Japanese encephalitis vaccine of mouse brain type might give rise preventive effect on the disease in nature in approximately 75 per cent. However, such a brain type vaccine was proved to contain possibly some factor to produce demyelinization following inoculation with the vaccine combined with Freund's adjuvant into guinea pigs. Accordingly the minimum requirement of the vaccine was revised to be prepared from the supernatant of 2 per cent emulsion of infected mouse brain following centrifugation at 3, 000 rpm for 30 min. Encephaligenic factor of such vaccine was remarkably minimized so that no more experimental demyelinization in guinea pig was encountered with this.
Herewith an attempt was made to elucidate immune response following injection of formalin killed mouse brain type vaccine of G-1 strain which was prepared following the method of the minimum requirement. G-1 strain of Japanese encephalitis virus was isolated from an encephalitis patient by us in 1949 and had been passed through mouse brain roughly by 200 generations. To criticize immune response by the vaccine, the vaccine was diluted to 1:1, 1:16 and 1:128 or 1:1, 1:10, 1:100 and 1:1, 000 and a group of mice was immunized with each dilution. Those immunized mice were divided into subgroups, and challenged with a series of 10 fold dilution of G-1 strain intracerebrally at 2 and 3 weeks after the initial immunization. On the other hand, neutralization, complement-fixation (CF) and hemagglutination inhibition (HAI) tests were carried out with pooled mouse sera from each group at 2 and 3 weeks after the initial vaccination. By comparing protection index (PI) with neutralization index (NI), CF and HAI antibody titers in mice at 2 and 3 weeks after the immunization with each dilution of the vaccine, those may be said:
1) The less PI and antibody titers were found in mice immunized with the higher dilution of vaccine at 2 weeks.
2) There was no significant difference in immune responses of mice vaccinated with both original and 10 times diluted vaccines. The minimum effective dose of the vaccine in mice was computed to be between 10 and 100 times dilution of the vaccine.
3) Comparing with immune responses each other in mice at 2 and 3 weeks, both PI and CF antibody titers reached their peaks at 2 weeks and fell down by 3 weeks, while both neutralizing and HAI antibody titers were found almost the same.
From the foregoing results it may be suggested that the effect of vaccine should be criticized on the basis of results obtained in mice first immunized with dilutions of vaccine of some range and then challenged with a series of virus dilution.

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1. 放射性同位元素P³²を用いて, モモアカアブラムシのダイコンモザイク病ウィルス伝播に関する実験を行つた.
2. P³²病ダイコンに5分間, 10分間吸汁モモアカアブラムシを5分間, 10分間づつ順次健全ダイコンに吸汁せしめると5-6番目の健全ダイコンまで発病し, P³²は10番目のダイコンまで移行することが認められた.
3. P³²病ダイコンに10分間吸汁モモアカアブラムシを1分間づつ順次健全ダイコンに吸汁せしめると15番目のダイコンまではウイルス伝染能力が認められ, P³²は15番目までアブラムシによつて移行した.
4. P³²病ダイコンに1分間吸汁モモアカアブラムシを1分間づつ順次健全ダイコンに吸汁せしめると, 8-9番目のダイコンまで伝染能力が認められ, P³²も同様な移行を示した.
5. P³²病ダイコンに30秒間吸汁モモアカアブラムシを30秒間づつ健全ダイコンに吸汁せしめると, 8番目のダイコンまで伝染能力があり, P³²は同様の移行を示した.

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In order to study on causal relation between polio virus and Guillain-Barré Syndrome encountered in the Setouchi area in 1953-1955, the comparative investigation of the isolation of polio virus from feces of patients with paralytic poliomyelitis and with G-B syndrome were attempted by means of roller tube cultures of human embrionic skin muscle.
7 strains of polio virus were isolated from feces of 9 polio patients and, of these, 5 were idemtified as type 1 and 2 as type 3; No viruses of the type 2 group were isolated from the material studied.
Only one strain of virus was isolated from feces of 9 G-B syndrome patients. However, this virus was not polio virus but ECHO virus. No polio virus of any type was isolated from feces of all G-B syndrome patients.
By referring to the study on the presence of the polio neutralizing antibody in the group of patients with paralytic poliomyelitis and of patients with the polyradiculoneuritis so-called G-B syndrome by Oyama, the Study on the interference phenomena between polio virus and Coxsackie virus by Ohara and above mentioned results, the pathogenesis of G-B syndrome was discussed.

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Difficulties were often encountered in carrying out hemagglutination inhibition test with Asian influenza virus, for there were non-specific inhibitors against Asian influenza virus in sera of many animals. In addition, the properties of the inhibitor appeared somewhat different from those of inhibitors so far described.
Following experiments were made in order to elucidate the nature of the inhibitor and to estimate its content in sera from various animals.
1) Hemagglutination inhibition titers of egg white and normal sera from nine species of animals against various strains of influenza virus were determined. Changes in their inhibition titers, after various treatments were also examined. A/Adachi/2/57, now used as a standard strain of Asian influenza virus in Japan, was readily inhibited by many of normal animal sera, especially in high titer by horse, swine and guinea pig sera.
2) The inhibitory activity was heat stable, destroyed neither by RDE (crude filtrate of the culture of V. cholerae) treatment nor by trypsin treatment, but was readily destroyed by KIO₄ treatment. Marked difference in its inhibition titer against live virus and indicator virus of A/Adachi/2/57 was not observed. A/Adachi/2/57 was neutralized by normal horse serum in embryonated eggs. The neutralizing activity was also inactivated by KIO₄ treatment. Based upon these results, the inhibitor against A/Adachi/2/57 is considered to be distinct from α and β inhibitors, and the term γ inhibitor was proposed. Comparison of properties of α, β and γ inhibitors and their contents in sera of various animals were diagramatically shown.
3) A correlation was found between hemagglutination inhibition by human antisera and that by inhibitor, at least with six strains of Asian influenza virus so far examined. A/Kumamoto/Y5/57, which was not inhibited by γ inhibitor in hemagglutination, was not also neutralized by γ inhibitor in embryonated eggs.
4) Addition of two volumes of M/100 KIO₄ to one volume of sample was recommended as a useful procedure in practice in order to remove γ inhibitor in hemagglutination inhibition test. This treatment did not seriously affect specific antibody titer.

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Variations in the sensitivities of lysogenic bacteria to X-ray during the growth cycle were investigated using two strains, lysogenic Shigella flexneri strain KA (βL) and nonlysogenic strain KA. The main results obtained were as follows.
(1) The radiosensitivity of the colony forming ability of rapidly dividing cells was markedly higher than that of resting cells in stationary phase.
(2) On the contrary, the sensitivity of the phage inducibility of the lysogenic strain KA (βL) to X-ray was found to be considerably lower when it was in logarithmic growth phase than in stationary phase.
(3) The survival curves measured by counting the visible colonies of both strains were similarly approximately single-hit type, indicated by their exponential inactivation kinetics.
(4) However the radiosensitivity of lysogenic strain KA (βL) for colony formation seemed to be superior than that of nonlysogenic KA, suggesting that the β phage induction may occur independently of the lethal mutation in the irradiated bacteria.

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The nature of ectromelia virus inactivated photodynamically was examined using the system of the virus-Ehrlich ascites cells.
1) The ectromelia virus is very sensitive to the photodynamic action of methylen blue.
2) The virus which has already entered the cells becomes resistant to the photodynamic action.
3) The inactivated virus has no interfering property.
4) The inactivated virus retains its immunogenical property.
5) The formation of inclusion bodies and the development of the inclusion bodies were suppressed in the immunized mouse even when the infection had already progressed for several hours in the normal mouse.

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Studies on the site of action of various antivirals including caprochlorone, chartreusin, 2, 5-dimethyl-benzimidazole, 5, 6-dichlor-1-b-ribofuranosyl-benzimidazole, myxoviromycin, canavanine sulfate and dinitrophenol were conducted against PR8 virus growth in chorioallantoic membrane and Sendai virus growth in L cells.
Firstly, these antivirals were tested against the growth of PR8 virus in a tissue culture system, consisting of 2.0ml of Hanks'solution and 4 pieces of chorioallantoic membrane together with the attached shell.
The results obtained in the system are as follows:
1) These antivirals in fairly high concentrations did not show any inhibitory tendency of viral hemagglutination. They were not virocidal and their inhibitory effect on the adsorption stage was also excluded as far as tested with 2 or more times of minimum inhibitory concentrations. Thus the inhibition of virus synthesis within the cell was suggested as the site of antiviral activities.
2) Determining the sensitive stage of the virus growth to these antivirals, chartreusin, 2, 5-dimethyl-benzimidazole and 5, 6-dichlor-1-b-ribofuranosyl-benzimidazole were grouped as an early active agent, and caprochlorone, canavanine sulfate, dinitrophenol and myxoviromycin were grouped as the late active antivirals. In other words, latter antivirals were active even when added at late stage of the incubation.
3) On the basis of calculating chemotherapeutic index, myxoviromycin was thought to be the best among these antivirals.
Secondly, these antivirals were examined their effect on the growth of Sendai virus in Earle's L cells.
The results obtained in the system may be summarized as follows:
1) All these antivirals showed the toxicity to L cells and the concentration which inhibited the growth of virus was around the vicinities of their toxic concentrations.
2) Both myxoviromycin and caprochlorone inhibited the cytopathogenic effect of the Sendai virus in addition to the inhibition of hemagglutinin production at critical concentrations. With other antivirals tested here, cytopathogenic effect of the virus was not affected even when the hemagglutinin production was impaired.
3) Myxoviromycin, in a wide range of concentration, showed the toxicity of low grade and within this range, the antibiotic inhibited the growth of the Sendai virus.

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Multiplication of poxvirus in vitro including ectromelia virus, vaccinia virus and variola virus were studied using chick embryo fibroblast, strain L cells and HeLa cells as host cells.
Relationships could be established among the growth cycle of virus determined by infectivity titrations, the cellular alterations under the conventional light microscopy and the presence of virus or materials of components associated with virus within the cells seen in the electron microscope.
In growth cycle experiments no increase in the amount of cell-associated virus was observed during the first 6 hours in any of the infectious systems used. A peak virus titer was attained in 15-to 18-hour-infection. Ectromelia and variola virus adsorped on the host cells were photographed using ultrathin sectioning. Intracytoplasmic inclusions (matrix) appeared 3 hours following infection, The first recognizable viral form, so-called developmental form, were exclusively observed within the matrix area in 6-hour-infection. Most of them were limited by a double membrane. Structural appearances of the nucleoid or viroplasm in stricted area were almost the A same as those of matrix material. Coiled thread measuring about 20 to 30Å in width were seen in them. Developmental form is matured infective virus or a vegetative phase of virus from the point of view of dynamic infectivity. At later stage of infection in ectromelia-fibroblast or-L cell system another quite different intracytoplasmic inclusions appeared which did not play a necessary role in viral multiplication.
Mature forms were observed in the matrix area in a later stage of infection. The structures of them show quite characteristic appearances and it is very easy to distinct from the developing form by the presence of two kinds of double membranes, by their shape, by smaller size and by rather stronger density in thicker sections. Experiments showed that so-called mature form appearing in a later stage was resting form of virus.

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1) During the course of the studies on the acute respiratory infection among children which were found in Tokyo area during the period between January, 1956 and February, 1958, isolation of causative virus from part of the sick children was attempted. Attempts were made on the throat washings and throat mucus collected from 5 cases who were diagnosed HVJ infection serologically. Two strains of HVJ were thus isolated.
Hazeyama strain was isolated by direct intraamniotic inoculation of the throat washing collected on the 1st day of disease from an 11 year-old boy who was suffering from acute laryngitis and exacerbation of acute nephritis, The identification of this strain to HVJ was made at the Fukumi Laboratory of the National Institute of Health.
Sakai strain was isolated by direct intraamniotic inoculation of throat mucus collected on the 5th day of disease from a 4 year 11 months old girl who was suffering from acute bronchitis. This strain was identified to HVJ by cross hemagglutination inhibition tests with antisera against influenza A and B viruses, mumps virus and HVJ. The reconvalescent serum of this case was negative in the HVJ complement fixation test even at the dilution of 1:4, but it was HVJ hemagglutination inhibition test positive up to the dilution as high as 1:1024.
2) Neutralization tests by fertilized hens'eggs were conducted by serum dilution method on 5 paired specimens randomiy selected from the specimens from cases of HVJ infection. In all cases, the convalescent serum showed distinct rise in the neutralizing antibody titer.
Within the 3rd week of the disease, neutralizing antibody titer, complement fixation titer and hemagglutination inhibition titer were found rising in parallel with each other, though complement fixation titer showed a tendency of falling thereafter. In the Case No. 3, the serum collected on the 144th day of disease showed negative results in the complement fixation test and hemagglutination inhibition test, but the neutralizing antibody titer was found still remarkably high. The above suggests that the neutralizing antibody titer and hemagglutination inhibition titer fluctuate not necessarily in parallel each other.

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Employing HVJ (Obayashi strain) vaccine inactivated with 1:10, 000 dilution of MERZONIN (sodium ethylmercurithiosalicylate), the pattern of the antibody production was observed on 50 healthy children at the age ranging from 8 to 15 years. The following results were thus obtained. In this instance, 50 healthy children matched by age were taken as controls.
1) Initial Immunization: Two intradermal injections of 0.1cc at the interval of 1 week demonstrated a significant rise in the hemagglutination inhibition titer (HVJ-HIT) in 5 out of 48 vaccinated cases (10.4%). In all of the cases, the complement fixation titer (HVJ-CFT) was negative even at the dilution of 1.2.
2) 1st Booster Immunization: As the results of the intradermal injection of 0.5cc 3 months after the initial immunization, a significant rise in the HVJ-HIT was recognized in 20 out of 47 vaccinated cases (42.6%). In all cases, no significant fluctuation in the HVJ-CFT was recognized.
3) 2nd Booster Immunization: As the results of 2 intradermal injections of 0.5cc each at the interval of 1 week 7 months after the 1st booster immunization, a significant rise in the HVJ-HIT was noted 17 days later in 21 out of 39 vaccinated cases (53.8%). Besides, a significant rise in the HVJ-CFT was noted in 13 out of 39 vaccinated cases (33.3%). One month later, both the HVJ-HIT and HVJ-CFT showed a tendency of falling, and all cases showed almost the same titer as that prior to the immunization 4 months later.
4) No statistically significant correlation was recognized between the infection of influenza A/Asia/57, which occured immediately after the 2nd booster immunization, and the antibody production effect, and between the mumps infection in the past and the antibody production effect of HVJ vaccine.
5) As side reaction of the immunization, excepting 1 case each of fever and vomiting after the 1st booster immunization, no serious general reaction was recognized at all. Further, all of the local reactions were only transient.
6) As stated in the above, in view of the high rate of antibody production effect and only slight side reactions, the inoculation of Merzonin inactivated HVJ (Obayashi strain) vaccine gave a favorable results comparable to those reported in the past about influenza vaccine.

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In order to clarify the correlationship in the antibody production against mumps virus and HVJ which was observed in the adult case of mumps, cases of HVJ infection, cases of mumps, cases immunized with both viruses, cases of cross infection, cases cross immunized with vaccine and clinical cases of various combinations of infection and immunization with vaccine were examined for the determination of the fluctuation of antibody level. As the results, the following findings were obtained.
1) In the cases of HVJ infection, regardless of the past infection of mumps, no significant fluctuation in the antibody level against mumps was recognized at all, though the subjects were all children. However, in the cases inoculated with HVJ vaccine, rise in the antibody level against mumps virus was recognized in 3 out of 5 children who experienced mumps in the past.
2) In the cases of mumps infection, regardless of the past infection of HVJ, no fluctuation in the antibody level against HVJ was recognized in the children, while in the adult cases of mumps, remarkable rise in the antibody level against HVJ was recognized in 1 out of 2 cases. In 2 cases of mumps who had been immunized with HVJ vaccine in the past, rise in the antibody level against HVJ was clearly recognized. Further. when children who had been immunized with HVJ vaccine in the past were immunized with mumps vaccine, rise in the antibody level against HVJ was recognized in 4 out of 7 cases. In 4 child cases who had clinically contracted mumps after the immunization with HVJ vaccine prior to the immunization with mumps vaccine, rise in the antibody level against HVJ was recognized when they were immunized with mumps vaccine.
3) In view of the above, the rise in the antibody level against HVJ which was seen in the adult mumps cases was considered to be due to the fact that the antibody level acquired at the time of HVJ infection rose as a group reaction when the antibody level against mumps virus rose.
4) Although numerous studies may be required in future to clarify the correlationship in the antibody production of HVJ and mumps virus, the serological diagnosis of HVJ infection in children is considered to be done far more readily almost without error when compared with that in adult cases.

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The kinetics of phage induction in some lysogenic strains of E. coli and Shigella was investigated by means of ultraviolet light (UV) irradiation. The main evidence to be noticed is the following.
(1) The kinetics of β phage induction in A34 (β, γ) was observed to be a kind of two-hit phenomenon, whereas that in an artificial lysogenic Shigella, strain KA (βL), single-hit phenomenon. The radiosensitivity of both lysogenic strains with respect to β phage induction was nearly equal each other.
(2) Under suitable UV dose, more than 80 per cent of the bacteria irradiated were induced with both two lysogenic strains.
(3) The number of β prophage in KA (βL) and A34 (β, γ) was estimated to be about 2 and 3-4 per bacterium, respectively.
(4) The descending portion of the induction curves is composed of two different parts, each of which is distinguished by its inclination, suggesting that the inactivation of phage production in overirradiated cells occurs by at least two different mechanisms.
(5) The UV sensitivity of bacteria tested as to phage induction and colony forming ability was markedly depend upon the physiological state of bacteria, for instance, inanition of the bacterial cells or growth phase of the culture, at the time of irradiation.

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A simple method for the staining of viral inclusion bodies was described.
Procedure:
(1) Fix in CARNOY's fluid, 10% formalin or absolute alcohol.
(2) Prepare paraffin sections in routine.
(3) Stain sections in 0.5% fuchsin S for 5 minutes.
(4) Wash off exess reagant in water for a moment.
(5) Treat with 1% phosphowolframic acid in destilled water for 20 minutes.
(6) Wash in water for a moment.
(7) Place in MAYER's hemalaum (hematoxylin) for 5 minutes.
(8) Wash in running water for 10 minutes.
(9) Dehydrate, clear and mount as usual.
Smear preparations can also be stained, but mount in Canada balsam or examine under microscope with oil immersion lens.
The ground substance of type A intracytoplasmic inclusion body (MARCHAL body) appeared deep scarlet in EHRLICH, YOSHIDA and sarcoma 180 ascites tumor cells, the chorioallantoic membrane of chick embryo, EHRLICH ascites tumor cells transplanted onto C. A. M., and the liver, other organs and tissues of mouse infected with ectromelia virus. The elementary bodies and the outline of type A intracytoplasmic inclusion body (BOLLINGER body) appeared deep scarlet in the C. A. M. of chick embryo and the skin of chick infected with fowlpox virus. The ground substance of this inclusion body was stained with neither fuchsin S nor hematoxylin. The type B intracytoplasmic inclusion bodies of these two kinds of viruses were not distinguished from the cytoplasm with this staining method. The classical type A intranuclear inclusion bodies appeared scarlet in the bronchial epithelium of monkey infected with measles virus and in the C. A. M. and the liver of chick embryo infected with herpes simplex virus. The inhalt of swollen nucleus infected with herpes simplex virus was stained slightly purple. Red blood cells and granules of eosinophilic leucocytes were stained deep scarlet. Nucleoli, some parts of degenerated cytoplasm and some of degenerated nuclei were also stained scarlet. Nuclei were stained deep blue. All others appeared faint purple.
By means of this staining the acidophilic inclusion bodies could be easily perceived.

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さきにサルモネラ O〔I〕 抗原を支配する因子は特定のtemperate phage遺伝子機構の中にあることを述べたが, この一連のファージが菌のO〔I〕 抗原のみならず, 菌の糖分解transduetionに預ること, 更にやや異つたカテゴリーに属すると思われる2, 3のtransductionについての成績を述べ遺伝学的考察を加えた.
1. O〔I〕 抗原支配ファージを鼠チフス菌或はパラチフスB菌 (これらはヅルチット分解) で増強して, S. pullorum Kauffmann No. 75 (ヅルチット非分解) を溶原化すると10^-8程度の割でヅルチット分解性のS. pullorumが得られた.
2. (1) のファージをS. pullorum K23 (P₃と略す) と共に培養すると, P₃はヅルチット非分解であるが, ヅルチット分解性のP₃菌が得られる. この際P₃菌は溶原菌であり (1) のファージでは溶菌されないが, (1) のファージを吸着する. こうした系でもtransductionは可能であり, この際prophageの種々のおきかわりを観察した.
3. 更にラムノーゼ分解の鼠チフス菌におけるtransductionの例をあげ, これらのtransductionについてその機転を考察した.

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