Antigens suitable for serodiagnosis of schistosomiasis japonica were investigated using immunoblotting in the course of the infections with Schistosoma japonicum in mice. Major antibodies to four adult worm antigens were found in the infected sera. Molecular weights of those antigens were determined to be 32 kD, 70 kD, 76 kD and 95 kD, respectively. Above all, antibody to the 32 kD antigen was first detected in mice sera 5 weeks after infection and was thereafter shown clearly in all of the infected mice sera throughout the experiment. From the results obtained in this study the 32 kD component was suggested to be the most useful antigen for the serodiagnosis of the disease.

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Thirteen human cases of Diplogonoporus grandis infection have already been reported from Kochi Prefecture, and in this report, additional eight cases occurring between 1985 and 1988 are described.
Since the first report on the human infection with D. grandis was given by Iijima and Kurimoto (1984) the total 130 human cases were recorded in Japan until 1988.
The cases of human infection with this cestode were distributed widely in the coastal areas along the Pacific Ocean and the Japan Sea in the central and the western parts of Japan. In contrast to other regions, Kochi Prefecture exhibits apparently a marked increase in the incidence of the cases in recent years.

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Taenia solium was successfully expelled from a 39-year-old woman by intraduodenal injection of gastrografin. This may be the first reported case of T. solium infection cured by gastrografin. On the other hand, gastrografin injection failed to expel Taenia saginata from a 38-year-old man, who had received gastrectomy 8 years ago. On this patient an endoscopic observation revealed presence of the worm in the upper jejunum, and the scolex was removed from the worm with biopsy forceps. The remaining part of the worm was expelled by the subsequent administration of a laxative. This may be the first case on which the cestode was observed by endoscopy and the scolex was removed with biopsy forceps.

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Chemotherapy by artemether, which was one of the qinghaosu (QHS, artemisinin) derivatives, was attempted in a case of severe falciparum malaria.
A Japanese 28 years old male, after making round trip in Africa, started fever attack one week before coming back to Tokyo. On the day of admission, he developed fever at 41°C, and asexual forms of P. falciparum were observed in the peripheral blood of the patient at a density of 17% of erythrocytes. His consciousness was turbid; cerebral malaria was suspected. Liver was palpable by two finger breadth but spleen was not palpable. Slight jaundice was observed. On the laboratory findings, anemia was remarked and a considerable degree of dysfunction of liver and kidney was also noted. By in vitro chloroquine susceptibility test, the isolate showed no resistance to chloroquine.
Quinine has been used as the drug of first choice to treat severe malaria. However we considered artemether is the antimalarial of higher priority than quinine especially in the treatment of patients with dysfunctions of liver, kidney and CNS, because side effects by quinine occasionally involve those organs. In addition, the half-life of quinine in the blood is 2.5 times as long as that of artemether, which again might endanger such patients. While artemether is documented to be remarkably well tolerated in man and also appears to be safe in the cases complicated by heart, liver, and renal disorders, because of the short half-life and rapid action of the derivative.
Two hundred milligram of artemether was administered on first dose intramusculary followed by 100 mg/dose at intervals of 12 hours to the amount totaling 1, 000 mg. The asexual stage parasites from blood films were eliminated in 66 hours after starting treatment, therefore, the patient already recovered from severity when administered artemether amounted to 600 mg which is the standard total dosage. When the clinical signs were away, the patient was supplemented by chloroquine administration, because recrudescence rate of artemether within one month is recorded higher than 10 per cent.
Most Japanese are non-immuners to malaria, hence tend to develop severe malaria if treatments delay. Artemether seems to be a promising new antimalarial with high potentiality to cure such patients.

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An aminopeptidase has been purified from membrane ghosts of mouse erythrocyte infected with Plasmodium berghei (NK-65 strain) by a simple method involving selective extraction with 1.0% Triton X-100, and chromatography on Sephadex G-100 and DEAE-Sephadex A-25. An enzyme activity is assayable conveniently with Ala-pNA or Leu-pNA as substrate at 405 nm.
1. This enzyme has a molecular weight of 100, 000 as measured by gel filtration on Sephadex G-100.
2. The enzyme is inhibited by bestatin and chymostatin, and slightly inhibited by E64 but not by pepstatin A, leupeptin and antipain.
3. The enzyme has an essential sulfhydryl group at the active site which is rapidly modified by Hg²⁺, and slowly by PCMB, but is unaffected by monoiodoacetic acid and N-ethyl-maleimide.

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BALB/c mice infected with L. donovani and ddY mice infected with T. gambiense were treated with inosine analogs (carbocyclic inosine and 3'-deoxyinosine) for appraising therapeutic effects. The mice infected with L. donovani promastigotes were treated with 5 different doses of each drug administered on alternate days. Four weeks after the infection, impression smear of the liver was prepared to determine the parasite load which was expressed as LDU by 1, 000 hepatic cell nuclei. In the mice infected with L. donovani, 3'-deoxyinosine 100 mg/kg i. v. showed about 63% effect as compared with the group of mice administered saline, and carbocyclic inosine 100 mg/kg i. v. showed about 92% effect as compared with saline. The mice infected with intraperitoneal injection of T. gambiense trypomastigotes were treated with drugs once a day for 4-8 days. The effect of drugs was measured by counting number of parasite on blood smear stained with Giemsa solution and survival rates of the mice. The group infected with T. gambiense and treated with carbocyclic inosine died all on the fourth day. On the other hand, 3'-deoxyinosine showed an effect to some extent. The mice treated with 3'-deoxyinosine showed twice longer survival time than the mice administered saline.

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