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Tae Yon Kim

Publications and source records attributed to Tae Yon Kim.

5 recordsLinked to original sources

Association of ALDH2 polymorphism with sensitivity to acetaldehyde-induced micronuclei and facial flushing after alcohol intake.

To investigate whether sensitivity to the induction of micronuclei by acetaldehyde is associated with genetic polymorphisms of the aldehyde dehydrogenase-2 (ALDH2) gene, cytokinesis-block micronucleus (CBMN) assays were performed on peripheral lymphocytes from 47 healthy human subjects exposed to acetaldehyde in vitro. Facial flushing following alcohol intake was analyzed to determine if it was correlated with ALDH2 gene polymorphisms. The frequencies of the ALDH2 genotypes ALDH2(1)/ALDH2(1), ALDH2(1)/ALDH2(2), and ALDH2(2)/ALDH2(2) were 66.0, 27.7, and 6.4%, respectively, in the 47 subjects. Therefore, 34% of the studied subjects carried the mutant allele ALDH2(2), which is associated with the lack of enzyme activity. The frequency of micronuclei induced by acetaldehyde increased in a dose-dependent manner with the largest increase seen in subjects that were homozygous for the ALDH2(2) allele. A significant association was observed between the ALDH2 genotype and alcohol-induced facial flushing. Average alcohol consumption of the study subjects was also associated with the ALDH2 genotype. The frequency of heavy drinking was significantly higher among subjects with the ALDH2(1)/ALDH2(1) genotype than among subjects with the ALDH2(2) allele (ALDH2(1)/ALDH2(2) and ALDH2(2)/ALDH2(2) genotypes). Alcohol-induced facial flushing was also associated with an increased frequency of micronuclei in lymphocytes treated with acetaldehyde. The results suggest that the ALDH2 genotype is significantly associated with acetaldehyde-induced micronuclei and alcohol-induced facial flushing.

Acetaldehyde↗

Bilateral spontaneous dislocation of intraocular lenses within the capsular bag in a retinitis pigmentosa patient.

A 45-year-old man with retinitis pigmentosa (RP), who had undergone uneventful extracapsular cataract extraction (ECCE) in his right eye eight years previously, and phacoemulsification in his left eye six years previously, had spontaneously dislocated intraocular lenses (IOL) within the capsular bag in both eyes one month apart. We removed the dislocated IOLs, and performed anterior vitrectomy and scleral fixation of the new IOLs. Mild contraction of the capsular bags and uneven distribution of the zonular remnants' clumps along the equator of the capsules were found by scanning electron microscopic (SEM) examination. In this study, we propose the correlation between RP and zonular weakness. To our knowledge, this is the first case report of bilateral spontaneous dislocation of IOLs within the capsular bag of an RP patient.

Adult↗

Overexpression of S100A4 is closely related to the aggressiveness of gastric cancer.

Elevated levels of the calcium-binding protein S100A4 cause metastasis of benign rat mammary tumor cells. To investigate whether S100A4 plays an important role in the invasion and metastasis of gastric cancers, we examined the gene mutations in the coding regions and expression patterns of the S100A4 in gastric adenocarcinoma in Korea. Moderate to strong expression of S100A4 was found in 53 (68.8%) of the 77 gastric adenocarcinomas, whilst normal gastric epithelium either failed to stain or showed weak staining. Interestingly, S100A4 expression was more frequently observed in gastric cancer patients with advanced gastric cancer (p=0.039), positive lymph node metastasis (p=0.001), and peritoneal dissemination (p=0.022). No gene mutations were found in the analyzed genomic area in 77 gastric adenocarcinomas and 15 gastric cancer cell lines. We found one single nucleotide polymorphism without an amino acid change, A99G, in two cases. These data suggest that the overexpression of S100A4 may be closely related to the aggressiveness of gastric cancer in Korea.

Adenocarcinoma↗

Cdk4 and p27Kip1 play a role in PLC-gamma1-mediated mitogenic signaling pathway of 18 kDa FGF-2 in corneal endothelial cells.

PURPOSE: To determine whether PLC-gamma1 enzyme activity is essential for cell proliferation in response to FGF-2 stimulation and to investigate the effect of PLC-gamma1 activation on cell division and on processes that regulate cell cycle progression. METHODS: Cell proliferation was assayed using a colorimetric method to determine the number of viable cells. Subcellular localization of proteins was determined by immunocytochemical analysis, and expression of the proteins was analyzed by immunoblotting. PLC activity was determined by measuring the total inositol phosphates. RESULTS: When CEC were treated with FGF-2, a prolonged and continuous FGF-2 exposure was required for both PLC enzyme activation and cell proliferation. However, there was a long lag period between the PLC enzyme activation and cell proliferation: the maximum enzyme activity was reached 8 h after FGF-2 stimulation, but no cell proliferation was observed in the cells exposed to FGF-2 for 8 h. Using neutralizing anti-PLC-gamma1, PLC-beta1, or PLC-delta1 antibodies, we further demonstrated that PLC-gamma1 accounts for the hydrolysis of total phosphoinositides (PI) and cell proliferation mediated by FGF-2. The role of PLC-gamma1 linking to the cell cycle was then determined by the blockades of FGF-2 action on Cdk4 and p27-Kip1. Interestingly, FGF-2 both upregulates Cdk4 synthesis and facilitates the nuclear import of the molecule from the cytoplasm, whereas it facilitates the nuclear export of p27-Kip1 to the cytoplasm without affecting synthesis of the molecule. The neutralizing anti-PLC-gamma1 antibody completely abolishes the FGF-2 activity on Cdk4, both at the synthetic level and at the level of translocation, and the PLC-gamma1 antibody blocks the nuclear export of p27-Kip1. CONCLUSIONS: These data indicate that PLC-gamma1 ultimately leads to activation of the cell cycle machinery to induce cell proliferation mediated by FGF-2. It does so by upregulating Cdk4 expression and by facilitating the nuclear import of the molecule and nuclear export of the Cdk inhibitor (p27-Kip1) to the proteolysis site, the cytoplasm.

Animals↗