Akedanones A-C, In Vitro and In Vivo Antiplasmodial 2,3-Dihydronaphthoquinones Produced by Streptomyces sp. K20-0187.

Three new antiplasmodial compounds, named akedanones A (1), B (2), and C (3), were discovered from the cultured material of Streptomyces sp. K20-0187 isolated from a soil sample collected at Takeda, Kofu, Yamanashi prefecture in Japan. The structures of compounds 1-3 were elucidated as new 2,3-dihydronaphthoquinones having prenyl and reverse prenyl groups by mass spectrometry and nuclear magnetic resonance analyses. Compound 1 and the known furanonaphthoquinone I (4) showed potent in vitro antiplasmodial activity against chloroquine-sensitive and chloroquine-resistant Plasmodium falciparum strains, with half-maximal inhibitory concentration values ranging from 0.06 to 0.3 µM. Compounds 1 and 4 also displayed potent in vivo antiplasmodial activity against drug-sensitive rodent malaria Plasmodium berghei N strain, with inhibition rates of 47.6 and 43.1%, respectively, on intraperitoneal administration at a dose of 5 mg kg-1 day-1 for 4 days.

New antimalarial iromycin analogs produced by Streptomyces sp. RBL-0292.

Two new antimalarial compounds, named prenylpyridones A (1) and B (2), were discovered from the actinomycete cultured material of Streptomyces sp. RBL-0292 isolated from the soil on Hamahiga Island in Okinawa prefecture. The structures of 1 and 2 were elucidated as new iromycin analogs having α-pyridone ring by MS and NMR analyses. Compounds 1 and 2 showed moderate in vitro antimalarial activity against chloroquine-sensitive and chloroquine-resistant Plasmodium falciparum strains, with IC50 values ranging from 80.7 to 106.7 µM.

Virgaricins C and D, new pramanicin analogs produced by Apiospora sp. FKI-8058.

Two new pramanicin analogs, named virgaricins C (1) and D (2), were discovered by physicochemical screening from a static cultured material of Apiospora sp. FKI-8058. Their structures were elucidated by MS and NMR analyses and chemical derivatization. Compounds 1 and 2 showed moderate antimalarial activity and cytotoxicity.

Electroconvulsive Therapy for Parkinson's Disease with Depression and Neuroleptic Malignant Syndrome: A Case Report.

Parkinson's disease is often complicated by psychiatric symptoms. Psychiatrists are caught in a dilemma between such symptoms and physical treatment since Parkinson's disease sometimes shows treatment resistance based on pharmacological treatment-induced dopamine dysfunction. Here, we report on a 64-year-old woman with a 15-year history of Parkinson's disease with stage IV severity based on the Hoehn and Yahr scale. She was admitted to our hospital with a diagnosis of major depressive disorder with psychotic features. Unfortunately, her treatment course for depression was complicated by neuroleptic malignant syndrome. Because we were concerned about the persistence of her depressive symptoms, the risk of psychotropic drugs causing adverse effects, and progressive disuse syndrome, we administered modified electroconvulsive therapy. Her symptoms of neuroleptic malignant syndrome and depression sufficiently improved after five sessions of modified electroconvulsive therapy. Additionally, the primary motor symptoms of her Parkinson's disease also markedly improved. The improvement of neuroleptic malignant syndrome and her motor symptoms based on dopamine dysfunction can be explained by electroconvulsive therapy's effectiveness in activating dopamine neurotransmission. Besides, the marked improvement of her depressive episode with psychotic features was presumed to involve dopamine receptor activation and regulation. Because advanced Parkinson's disease can sometimes be refractory to treatment based on pharmacological treatment-induced dopamine dysfunction, psychiatrists often have difficulty treating psychiatric symptoms; electroconvulsive therapy may stabilize the dopaminergic system in such cases, presenting a possible non-pharmacologic treatment option for Parkinson's disease.