- 著者
- Hiroshi Jinguji Yuki Fujiwara Kazuhisa Ohtsu Moono Shin Motoko Morimoto
- 出版者
- The Japan Society of Medical Entomology and Zoology
- 雑誌
- 衛生動物 (ISSN:04247086)
- 巻号頁・発行日
- vol.72, no.3, pp.199-204, 2021-09-25 (Released:2021-09-14)
- 参考文献数
- 49
- 被引用文献数
- 1
The increase in the number of imported cases of dengue fever in Japan is of particular concern as Aedes albopictus is a vector of dengue fever. Due to the potential for insecticide resistance and the impact of insecticides on non-target species, increased attention is being paid to alternative methods of pest control. Placing salt in used tires has been recommended by the Ministry of Health, Labor and Welfare in Japan as a means of controlling mosquitoes. However, the effectiveness of salt as a larvicide against Ae. albopictus are currently unclear. This study examined the acute toxicity of sodium chloride against first and fourth larval instars of Ae. albopictus. Acute toxicity tests were conducted according to World Health Organization guidelines. The susceptibility of Ae. albopictus larvae was tested against 0.25%, 0.5%, 0.75%, 1.00%, 1.25% and 1.5% NaCl solutions. Larval mortality was correlated with an increase in NaCl concentration and exposure duration. First instar Ae. albopictus larvae were more sensitive to NaCl than fourth instar, and 72-h LC90 values for first and fourth larval instars were 0.49% and 1.01% NaCl, respectively. Our results suggest that the application of 0.5% NaCl to a habitat for 3 days is effective for Ae. albopictus control.
- 著者
- Kanae NIIMI Motoko MORIMOTO
- 出版者
- JAPANESE SOCIETY OF VETERINARY SCIENCE
- 雑誌
- Journal of Veterinary Medical Science (ISSN:09167250)
- 巻号頁・発行日
- vol.83, no.4, pp.573-580, 2021 (Released:2021-04-09)
- 参考文献数
- 25
- 被引用文献数
- 3
To eliminate pathogens, the initiation of an appropriate immune response is critical. When the gastrointestinal nematode, Heligmosomoides polygyrus (Hp), invades the small intestine, a type-2 cytokine response is initiated; however, this response is not sufficient to clear the infection, and chronic infection can ensue. In this study, the host defense against Hp was investigated in mice with a focus on the role of CD4+ T cells. To this end, tissues from the small intestine and mesenteric lymph node (MLN) were collected every day from just after infection until Day 5 because many previous studies have described the later stages of infection from Day 8 to Day 12, during which Hp returns to the lumen and Th2 cytokine expression reaches its peak. In this study, we focused on investigating the initiation of the type-2 immune response. Our results indicated that the larvae encysted by Day 3. Increased type-2 cytokine gene expression started in the small intestine before Day 2 and increased again on Day 5. Interferon (IFN) γ increased significantly on the second day. Flow cytometry and gene expression analysis of MLN cells revealed that CD4+ T cells were not activated until Day 4. These results suggested that innate immune cells in submucosa are activated immediately after infection, but CD4+ T cells accumulate in the cyst zone later. In addition, IFNγ may have an important role in converting type-2 cytokine-producing cells from innate cells to CD4+ T cells.