1.Morphological and Molecular Characteristics of the Oak Tree Canker Pathogen, Annulohypoxylon truncatum.
Jaeyul CHA ; Bitna HEO ; Soo Jeong AHN ; Guenhye GANG ; Chung Gyoo PARK ; Youn Sig KWAK
Mycobiology 2012;40(1):79-81
Cankers are localized dead areas in the bark of stems, branches or twigs of many types of trees and shrubs, and are usually caused by fungi. We observed severe canker symptoms in oak trees located in Gyeongnam province in 2011. A total 31 trees were discovered with cankers of varied size, with an average of 48.5 x 15.2 cm. Black, half-rounded globular mound shaped stromata were associated with the cankers, and the asci of the fungi associated with the cankers were cylindrical shaped with their spore-bearing parts being up to 84 microm in length. The average fungal ascospores size was 7.59 x 4.23 microm. The internal transcribed spacer sequence for the canker causing fungus showed 99% similarity to the sequence of Annulohypoxylon truncatum. In this study, the isolated fungus was precisely described and then compared with fungi of similar taxa.
Fungi
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Quercus
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Trees
2.Dipenyleneiodonium Induces Growth Inhibition of Toxoplasma gondii through ROS Induction in ARPE-19 Cells
Pu Reum SUN ; Fei Fei GAO ; Hei Gwon CHOI ; Wei ZHOU ; Jae Min YUK ; Jaeyul KWON ; Young Ha LEE ; Guang Ho CHA
The Korean Journal of Parasitology 2019;57(2):83-92
Based on the reactive oxygen species (ROS) regulatory properties of diphenyleneiodonium (DPI), we investigated the effects of DPI on host-infected T. gondii proliferation and determined specific concentration that inhibit the intracellular parasite growth but without severe toxic effect on human retinal pigment epithelial (ARPE-19) cells. As a result, it is observed that host superoxide, mitochondria superoxide and H2O2 levels can be increased by DPI, significantly, followed by suppression of T. gondii infection and proliferation. The involvement of ROS in anti-parasitic effect of DPI was confirmed by finding that DPI effect on T. gondii can be reversed by ROS scavengers, N-acetyl-L-cysteine and ascorbic acid. These results suggest that, in ARPE-19 cell, DPI can enhance host ROS generation to prevent T. gondii growth. Our study showed DPI is capable of suppressing T. gondii growth in host cells while minimizing the un-favorite side-effect to host cell. These results imply that DPI as a promising candidate material for novel drug development that can ameliorate toxoplasmosis based on ROS regulation.
Acetylcysteine
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Ascorbic Acid
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Humans
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Mitochondria
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Parasites
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Reactive Oxygen Species
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Retinaldehyde
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Superoxides
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Toxoplasma
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Toxoplasmosis