Expression of Gpnmb in NK Cell Development from Hematopoietic Stem Cells

BACKGROUND: Molecular mechanisms of natural killer (NK) cell development from hematopoietic stem cells (HSCs) have not been clearly elucidated, although the roles of some genes in NK cell development have been reported previously. Thus, searching for molecules and genes related NK cell developmental stage is important to understand the molecular events of NK cell development. METHODS: From our previous SAGE data-base, Gpnmb (Glycoprotein non-metastatic melanoma protein B) was selected for further analysis. We confirmed the level of mRNA and protein of Gpnmb through RT-PCR, quantitative PCR, and FACS analysis. Then we performed cell-based ELISA and FACS analysis, to know whether there are some molecules which can bind to Gpnmb. Using neutralizing antibody, we blocked the interaction between NK cells and OP9 cells, and checked IFN-gamma production by ELISA kit. RESULTS: Gpnmb expression was elevated during in vitro developmental stage and bound to OP9 cells, but not to NK precursor cells. In addition, we confirmed that the levels of Gpnmb were increased at NK precursor stage in vivo. We confirmed syndecan4 as a candidate of Gpnmb's binding molecule. When the interaction between NK cells and OP9 cells were inhibited in vitro, IFN-gamma production from NK cells were reduced. CONCLUSION: Based on these observations, it is concluded that Gpnmb has a potential role in NK cell development from HSCs.

Loss of Heterozygosity at VHL, FHIT, and p16 Loci in Nonpapillary Renal Cell Carcinoma

The objectives of this study were to characterize the alterations of 3p and 9p in sporadic renal cell carcinomas (RCC) and to assess the relationship between the clinical stages or tumor size and the alteration of these chromosomes. Thirty eight archival, paraffin embedded tissue sections from 38 patients with RCC were analyzed for loss of heterozygosity (LOH) at 3p and 9p with 11 microsatellite markers. LOH was detected in 81.6% (31/38) and 37.8% (14/37) at 3p and 9p, respectively. The frequencies of LOH at VHL and FHIT locus were 75.6% and 72.2%, respectively. Twelve cases out of 38 showed LOH at both 9p21 and 3p. The loss of 3p in the samples tested was not related to clinical stages and tumor size, but that of 9p21 was significantly associated with advanced stage and larger tumor size. These results support that 3p deletion, including VHL and FHIT gene, play a critical role in the tumorigenesis of sporadic RCC, especially at early stage, and that 9p21 may contribute to the progression of sporadic RCC.

HgCl2 Toxicity on Cultured Renal Tubular Cells of Rabbit

To understand the mechanism of cell injury when exposed to HgCl2, monitoring of cytosolic ionized free Ca2+([Ca2+]i), viability test, measurement of the amount of ATP, and Ca-ATPase activity were evaluated in cultured rabbit renal tubular cells(RTC) exposed to HgCl2. The results were as follows: 1) HgCl2 was cytotoxic to rabbit RTC at all doses except 10 uM and the rate of killing displayed a dose- and time-dependent relationship. 2) The absence of extracellular Ca provided partial protection from irreversible injury induced by HgCl2. 3) The increasing pattem of [Ca2+]i varied according to the concentrations of HgCl2. At the low concentrations of HgCl2 (2.5-10 microM), the level of [Ca2+]i increased slowly over the flat 2-3 min and then achieved plateau-state. In contrast, at the high concentrations of HgCl2 (25-100 microM) the level of [Ca2+]i achieved peak within 1 min and then decreased to a plateau state under normal concentrations. 4) The level of ATP was decreased to 27.5% of that of normal control cells within 3 min by using a treatment of 100 microM HgCl2. 5) HgCl2 did not affect the Ca2+ ATPase activity by enzyme histochemical observation. These findings suggest that the elevation of [Ca2+]i in response to the HgCl2-induced injury is an important event in accelerating injury that ultimately leads to cell death. But other possibilities such as HgCl2 might have direct deleterious effects on the also should be considered.

An Anslysis of Operative Patients after Enforcement of Medical Insuranes System / 대한마취과학회지

12,688 cases of operative patients who received operation at kyungpook National University Hospital from Jul. 1977 to Dec. 1981 were analyzed according to each year, each surgical department, anesthetic technique, and the ratio of medical insurance patients after enforcement of medical insurance system. 1) Total operative patients were 12,688 cases including general patients 7,084 cases(54%) insurance patients 3,934 cases(31%), public assistance recipient 906 cases(7%), and industrial accident patients 764 cases(6%). 2) Total patients and insurance patients increased annually, while general patients decreased gradually. 3) Though regional and general anesthetic cases of general patients, decreased annually, those of insurance patients increased year by year. 4) Among the surgical department, the highest rate wwas neurosurgery 850 cases(73%) in general patients, E.N.T. 354 cases(54%) in insurance patinets, chest surgery 94 cases(17%) in public assistance recipient, and orthopedic surgery 350 cases(17%) in industrial accident patients. 5) E.N.T. department showed largest increase in insurance patients among surgical sections.