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We previously showed that human hepatic intrasinusoidal (HI) natural killer (NK) T cells selectively eliminate hepatocellular carcinoma (HCC) cell lines. In this study, we investigated the underlying mechanisms on how HI γδ T cells, expanded with zoledronate, exhibit a superior cytotoxic effect on HI NK-resistant Huh7 HCC cells.γδ T cells were obtained from living liver transplant donors or from peripheral blood mononuclear cells (PBMC) of healthy volunteers and were expanded in the presence of IL-2, IL-15, and zoledronate for 2 weeks. Cytotoxicity was measured using the lactate dehydrogenase (LDH) assay in vitro and by flow cytometry using carboxyfluorescein succinimidyl ester (CFSE) in vivo.The cytotoxicity of expanded HI γδ T cells against Huh7 cells was associated with a higher pyrophosphate expression in Huh7 cells compared to SNU398 cells. In contrast, the cytotoxicity of HI γδ T cells against SNU398 cells depended on NKG2D. HI γδ T cells expressed less PD-1 than PB γδ T cells. The cytotoxicity of HI γδ T cells against Du145 and PC3 prostate cancer cells was also associated with pyrophosphate expression in these cells, as well as NKG2D and DNAM-1.The expression levels of phospho-antigen in tumor cells determined the cytotoxicity of HI γδ T cells, although the NK activating receptors, death ligands, and immune checkpoint molecules also contribute to their cytotoxicity. γδ T cells are attractive candidates for cancer immune cell therapy.

This paper presents a general model of the determination of the interest rate and the exchange rate which is relevant for a small economy with any degree of capital mobility. The model is tested by using the quarterly data of Korea and Singapore. The emperical results show that in the Korean case changes in money supply affect the interest rate, but do not affect the exchange rate, while in the case of Singapore the domestic interest rate is determined by the foreign interest rate and the expected change in the exchange rate, as well as by changes in the money supply; changes in the money supply also influence the exchange rate. The results imply that the progress of capital liberalization in a small country will alter the transmission mechanism from reliance on the interest rate channel alone to effects arising through both the interest rate and the exchange rate.

In the modern technological industrial society, utilization of fire is indispensable to the daily life nowadays. However, features of the industrialised society impose a big threat to the safety of human life, and thus require a more advanced means of fire-fighting administration. In regard to the characteristics of the fire-fighting, prevention and extinguishment of fires, major tasks for each have been outlined as: fire safety management, hazardous materials safety management, and advertising for the former; deployment of fire-fighting apparatus to the scene of the fire in a quick and safe manner. Current problems involved in such tasks have been made clear as the lack of devices or capabilities of scientific cause-finding laboratory work, and resultant chance of false assumptions. In addition to worn-out equipments, such things as follow have been added to the present problems: insufficient manpower; lack of water sources; obstacles to handle emergency calls; absence of tactics and instructions; and lack of self-extinguishing activities. Considering such defects in current administration, recommendations have been made as follow; 1) reorganization of the Ministry of Home Affairs and local governments so that professional personnels may more efficiently contribute to the fire-fighting today; 2) enlargement and enforcement of research and education function; 3) establishment of more efficient allotment of manpower far the mission; 4) securing proper water systems; 5) developing tactics for response in emergency; 6) securing of co-ordination of fire-fighters and civilians. In sum, ways of improving the attitudes of personnels engaged in fire-fighting; equipments, adequate training; and nation-wide telecommunication systems, have to be contrived for the future.