Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Section||University-to-University Cooperative Research|
|Research Institution||University of the Ryukyus|
FUKUNAGA Toshihiko Department of Virology, Faculty of Medicine, 医科部, 教授 (10029796)
NIWAT MANEEK チェンナイ大学, 医学部, 准教授
CHIRASAK KHA チェンマイ大学, 生命科学研究所, 所長
MAKINO Yoshihiro Department of Virology, Faculty of Medicine, 医学部, 助教授 (60039930)
SATO Yoshiya Depratment of Parasitology, Faculty of Medicine, 医学部, 教授 (60092699)
IWAMASA Teruo Department of Pathology II, Faculty of Medicine, 医学部, 教授 (10110842)
KHAMBOONRUANG Chirasak Research Institute for Health Sciences, Chiang Mai University
MANEEKARN Niwat Department of microbiology, Faculty of Medicine, Chiang Mai University
NIWAT Maneek チェンマイ大学, 医学部, 准教授
CHIRASAK Kha チェンマイ大学, 医学部, 教授
SITHISOMBUT ノポーン チェンマイ大学, 医学部, 講師
MANEEKARN Ni チェンマイ大学, 医学部, 准教授
CHIOWANICHI ピエン チェンマイ大学, 医学部, 教授
大鶴 正満 琉球大学, 医学部, 客員教授 (60018281)
|Project Period (FY)
1990 – 1992
Completed(Fiscal Year 1992)
|Budget Amount *help
¥5,000,000 (Direct Cost : ¥5,000,000)
Fiscal Year 1992 : ¥1,600,000 (Direct Cost : ¥1,600,000)
Fiscal Year 1991 : ¥1,600,000 (Direct Cost : ¥1,600,000)
Fiscal Year 1990 : ¥1,800,000 (Direct Cost : ¥1,800,000)
|Keywords||Japanese encephailtis / Dengue hemerrhgic fever / Cross immune response in flavivirus infections / RT-PCR / Expressed protein by baculovirus system / Heres simplex virus type 2 / Strongyloidiasis / Serodiagnosis of strongyloidiasis / 糞線虫症の血清学的診断法 / 単純ヘルペスウイルスII型 / 単純ヘルペスウイルスII型の病原性 / 日本脳炎(JE) / デング出血熱(DHF) / 単純ヘルペスウイルスII型(HSVーII) / 分子疫学 / 診断用発現蛋白|
The cooperative study consists of three fields : 1. Flavivirus infections, specifically Japanese encephalitis(JE) and dengue hemorrhagic fever(DHF). 2. Herpes simplex virus type 2(HSV 2) infection. 3. Strongyloidiasis.
Results obtained are described briefly as follows :
1. Cross immune response between JE and DHF was examined by neutralization(N) tests. When individuals with pre-existing N antibody to JE or dengue virus were infected sequentially with dengue or JE virus, significant increases of N titer were observed not only to the causative virus but also to the previously infected virus at the frequency of 35%-40%. Thus, even the N test could not always identify the causative virus in re-infection of flaviviruses.
The truncated dengue-4 E protein produced by a recombinant baculovirus was wxamined for the possibility of diagnostic antigen to differentiate dengue and JE infection. Results indicated that the expressed protein was a useful diagnostic antigen in differentiation of dengue in
fection from JE with slightly lower specificity than N test.
RT-PCR method was examined for the early diagnosis of DHF. Appropriate selections of primers for RT-PCR resulted in a useful identification method of 4 serotypes of dengue virus in comparison with virus isolation.
2. HSV 2 isolates in Okinawa and Chiang Mai were analyzed by the restriction endonuclease cleavage patterns and virulence to mice. Some cleavage patterns characteristic to each regional isolate were observed. The Okinawan isolates showed higher, intermediate and lower virulence while the Chiand Mai isolates showed only intermediate virulence to mice by peripheral injection
3. Field study on strongyloidiasis in Chiang Mai gave positive rates of 46.3% in adult villagers and 6.9% in school children.
The newly developed ELISA for strongyloidiasis gave well-corresponding results with those of the stool culture examination for the Okinawan samples but did not for the Chiang Mai samples, possibly due to cross reactions caused by co-infections with other intestinal parasites such as Opisthorchis viverrini and hookworm, which were found to be highly prevalent in the Chiang Mai area. Less