• Clinical and Experimental Pediatrics
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• v.49 no.2
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• pp.181-186
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• 2006

Purpose : The hematologic change during the treatment of acute lymphoblastic leukemia(ALL) is critical as a prognostic determinant and a variable to determine the dose of chemotherapeutic agents. It is known that the dose of vincristine used in the maintenance phase of ALL is small enough to increase the count of platelet. To investigate the change of platelet count according to the vincristine administration in maintenance phase of ALL chemotherapy, we performed this study. Methods : Eleven patients eligible under the criteria of Children's Cancer Study Group(CCG)-1882 and who had completed chemotherapy were enrolled in this study. The count of platelets before vincristine administration was compared with those of vincristine administration 1, 2 and 3 weeks after the early and last periods of maintenance phases. The platelet count before vincristine administration was defined as 100 percent and that after vincristine were compared. In addition, we tentatively defined an enhancing effect of vincristine as positive when the relative count was more than 120 percent. Results : Platelet count did not differ according to the early and last periods of maintenance phase. Platelet count at first week after vincristine administration increased more significantly than that before vincristine in early and last periods. There was an enhancing effect in 10(90.9 percent) of 11 patients after 1 week vincristine administration both in the early and last periods of the maintenance phase. Conclusion : Vincristine, used in ALL maintenance phases as a low dose, increased platelet count 1 week after administration. The increased platelet count resumed to the previous level 2-3 weeks later. However, the thrombocytosis observed in the maintenance phase by vincristine was not high enough to induce thrombosis. In addition, vincristine is known to reduce the activity of platelets. Therefore, the risk of thrombosis in the maintenance phase of ALL chemotherapy would be low.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.439-445
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• 2006

Purpose : ${\alpha}$-Galactosylceramide (${\alpha}$-GalCer)-stimulated human $V{\alpha}24$ natural killer T (NKT) cells exert antitumor activity against some leukemia in a CD1d dependent and TCR-mediated manner, but could not kill CD1d - negative neuroblastoma (NB) cells. There are few reports about the direct antitumor effect of highly secreted cytokines by these cells on activation. In this study, using a cell-free supernatant (SPN) collected from plate bound hCD1d/${\alpha}$ GalCer tetramers-stimulated NKT cells, we examined whether they could be helpful in the immunotherapeutic treatment of NB. Methods : Cells were cultured in IMDM. The cytokines produced by NKT cells were measured with Cytometric Bead Array (CBA) analysis. Cell viability was evaluated by calcein-AM fluorescence with digital image microscopy scanning (DIMSCAN). The percentage of specific apoptosis was calculated by flow cytometric detection of apoptosis using annexin V and 7-AAD. Results : The activated NKT cells secreted high levels of IL-2, INF-${\gamma}$, TNF-${\alpha}$. The SPN was significantly cytotoxic against four out of eight tested NB cell lines, through mainly apoptosis as evidenced by annexin-V staining and inhibition with the pretreatment of pancaspase blocker. This apoptosis was significantly inhibited when anti-TNF-${\alpha}$ and anti-IFN-${\gamma}$ neutralizing mAbs were used separately and it was completely abolished when the two mAbs were combined. Conclusion : IFN-${\gamma}$ and TNF-${\alpha}$ produced by NKT cells could exert synergistically direct antitumor activity through apoptosis on some NB cell lines.

• Journal of Preventive Medicine and Public Health
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• v.26 no.2 s.42
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• pp.222-230
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• 1993

Industrial glues, known as 'Bonds' in Korea, contain many kinds of organic solvents, and glue sniffing of youths became one of the social problems in Korea. Mixed exposures to solvents by glue sniffing may induce chronic toxicities different from those by exposures to solvents of single component. To test effects of the glue sniffing on weight gain or central nervous system, two groups of 20 male Sprague-Dawley rats were exposed to air(control group) or vapors of the glues to narcotic status(exposed group), and weight check, tail flick test, hot plate test, rotarod treadmill test were done on the 14th,24th, 36th, 45th, 53rd, 86th, 102nd, 117th, 134th and 151st days after the first exposure. On the 188th day, their brains were excised and examined by a pathologist. Weight gain, controlled against time change, showed significant difference between the groups, but response times in tail flick test, hot plate tests, and rotarod treadmill test didn't. In pathological examination with blind method, no macroscopic or microscopic differences were found between the two groups. These results suggests that organic lesion in central nervous system may not ensue glue sniffing, but, before firm conclusion, more studies in various exposure conditions should be followed.