Lymphokines (Spl-LKs) capable of inhibiting toxoplasma multiplication in homologous cell monolayers in vitro exist in the supernatant of spleen cells from toxoplasma immune animals incubated either with toxoplasma lysate antigen (TLA), or with non-specific mitogens (4, 10, 12-15). Contained in the Spl-LKs is a toxoplasma growth inhibitory factor, Toxo-GIF (15), approximately 30, 000 to 40, 000 m. w., which inhibits toxoplasma multiplication in homologous but not in heterologous cells, thus showing species specificity (10).
Recently, circulating interferon (IFN) has demonstrated antiviral activity not only in homologous but also in heterologous cells (1, 2). In the authors' previous reports (11, 12, 18), the activity of gamma-interferon (IFN_-r) in the circulation of toxoplasma immune animals reached its maximum after 6 h while the Toxo-GIF activity peaked 24 to 48 h after TLA injection. The relationship of Toxo-GIF to IFN_-r, both of which are found in the same serum, had not yet been clarified. Based on the above observations, an attempt was made to determine whether immune serum, chemically hydrolyzed to its low-molecular components via enzymes and acid-alkaline hydrolysis, would inhibit toxoplasma multiplication not only in homologous but also in heterologous cells. It also aimed at detecting IFN activity from the same hydrolyzed samples.
Evidence was presented on the production and properties of Toxo-GIF and IFN in the circulating blood of toxoplasma immune mice, following the intraperitoneal injection of TLA. The IFN elaborated by this method was designated IFN_-r. This study deals mainly with some biologically active substances derived from hydrolyzed toxoplasma immune mouse serum (HS-LKs) or hydrolyzed spleen cell cultured lymphokines (HSpl-LKs) and their effects on parasite growth not only in homologous but also in heterologous cells. The HS-LKs and HSpl-LKs, approximately 3, 000-5, 000 m.w., strongly inhibited toxoplasma multiplication in homologous cells, without cytotoxicity, when administered in concentration of 0.5% or less. This substance, or substances, also inhibited toxoplasma multiplication in heterologous monolayers of bovine monocytes, canine monocytes and human heart cells. This ability to inhibit toxoplasma multiplication in homologous and heterologous cells was derived not from IFN_-r, but from Toxo-GIF or aToxo-GIF-like substance.

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The specimens of two species of adult mosquitoes, Mansonia (Mansonioides) uniformis and Mansonia (Coquillettidea) ochracea were collected by the dry-ice collection method and the light-trap collection method at the Midoroga-ike pond which is situated in the northern part of Kyoto City from February to November in 1964. Seasonal flight activities of Mansonia (Mn.) uniformis were seen at this pond from the end of May to the beginning of October. Seasonal variation of wing-length of adult females of Mansonia uniformis were observed that the wing-length is longer in spring and autumn than in summer as well as in the case of Culex tritaeniorhynchus.
Namely it seems to be that Mansonia mosquitoes are hibernated in adult stage in their life cycle. Mansonia uniformis is attractived to CO₂ strongly, while Mansonia ochracea is aggregated to the light-trap collection method. Therefore, it is clarified that there are two different type of taxis i.e. chemotaxis for Mansonia uniformis and phototaxis for Mansonia ochracea.

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One of the arginine ester hydrolases (TAME hydrolases) of Trimeresurus mucrosquamatus venom was isolated by a combination of gel filtration on Sephadex G-100, ion exchange chromatographies on CM-Sephadex C-50, DEAE-Sephacel and chromatofocusing on PBE 94. From 2 g of the venom 10.1 mg of purified TAME hydrolase, ME-4 was obtained. The substrate specificity of ME-4 was strictly directed to the hydrolysis of arginine ester. The esterolytic activity was inhibited by benzamidine, p-tosyl-L-phenylalanine chloromethyl keton (TPCK) or diisopropyl fluorophosphate (DFP).
ME-4 was proved to be homogeneous by electrophoresis on polyacrylamide gel and isoelectric focusing. The molecular weight was found to be about 28, 500. Its isoelectric point was 5.31. This enzyme was a glycoprotein. The esterolytic activity of the final preparation was 152.5 units/mg (substrate; TAME). This enzyme had capillary permeability-increasing and kinin-releasing activities, but not clotting activity. This protein was stable to heat treatment, and between pH 4 and 12. Its Michaelis constant (Km) for TAME and inhibition constants (Ki) for benzamidine, DFP and TPCK were found to be 25.0×10^-3 M, 0.63×10^-3 M, 4.44×10^-3 M and 0.57×10^-3 M, respectively.

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Life cycle of African ticks, Ornithodoros moubata as a vector of Dipetalonema viteae were studied on 1) blood sucking time, 2) rate of body weight change, 3) production of eggs, 4) rate of sex after blood suck and 5) rate of hatching time under the condition of continuous light and continuous darkness, and 14 hours light and 10 hours darkness at different temperatures (21°C 27°C, 32°C and 36°C).
As the result, the different condition of light shows no effect upon the life of O. moubata, while the suitable temperature of O. moubata for long life is between 27°C and 32°C and for the longest one, 21°C.

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Anthropometric measurements, measurements of skin temperatures and rectal temperature at 30°C and measurements of physiological responses to heat were made on 30 young male residents of Okinawa who were born and raised in Okinawa (Group O) and 30 young male residents of Okinawa who were born and raised in main islands of Japan but move to Okinawa less than two years (Group M) in summer. Sweating reaction was examined for 60 min by immersing both legs in stirred water bath of 42°C in room of 30°C and 70 R. H. Group O showed thinner skinfold thickness, slender body shape, higher skin temperature at 30°C, smaller sweat volume with lower Na concentration in sweat, less rise in core temperature, and less increase in heart rate during heat exposure than group M. It is assumed that group O might have superior capacity for nonevaporative heat dissipation and better efficiency of sweating for cooling the body that group M. It is concluded that the acclimatization to heat of subjects in group O, subtropical natives, had advanced further than those in group M, immigrants of temperate natives to subtropical zone, and heat tolerance of the former is superior to that of the latter.

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The biting activity of four zoophilic species of Simulium was examined in an area endemic for human onchocerciasis in Guatemala, using bovine baits. The surveys were performed at three sites within San Vicente Pacaya county (SVP) from daylight until nightfall of two days in January 1979. A total of 8, 203 blackflies were collected from the baits throughout the collections. Of these flies, 6, 531 (79.6%) were Simulium metallicum s. 1.; 977 (11.9%), S. pulverulentum; 654 (8.0%), S. callidum; and 41 (0.5%), S.rubicundulum. Biting activity of S. metallicum s. 1. peaked between 0800 to 0900 hours and a second peak was noted between 1500 to 1600 hours. S. callidum also exhibited two peaks, one in the morning and the other, more pronounced, in the late afternoon, immediately before the night-fall. The remaining two species, S. pulverulentum and S. rubicundulum were mainly mid-morning attackers of cattle. Thus, the rate of species composition was presumed to differ within a day.

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The rapid titration method of the infectivity and the neutralizing antibody of rabies virus was established by the use of immuno-peroxidase (biotin-avidin-peroxidase) staining technique in microslide culture chambers. This method offers high sensitivity and reproducibility and would provide a new mean for the rapid diagnosis of rabies and the seroepidemiology of rabies virus.

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