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Y T Kim

Publications and source records attributed to Y T Kim.

At least 37 records · Page 2Linked to original sources
PubMed2001

Cloning and sequence analysis of the interleukin-8 gene from flounder (Paralichthys olivaceous).

A cDNA library of mRNA from flounder leukocytes stimulated with bacterial lipopolysaccharide (LPS) and hemagglutinin was constructed to clone cytokine genes of this fish. Initial screening of this library with human cytokine gene probes was not productive and clones with inserts of over 400 nucleotides (nt) were randomly sequenced, and a homologue of the vertebrate interleukin-8 (IL-8) gene was isolated. The flounder IL-8 cDNA encompassed 884 nt, including a coding region of 330 nt. Four cysteines characteristic of CXC chemokines were identified at conserved locations in the putative protein. The deduced amino acid sequence showed 36 and 35% sequence identity with counterpart genes in monkey and human, respectively, and 52% sequence similarity with these genes. However, the putative flounder IL-8 amino acid sequence showed 25% identity and 52% similarity to that of lamprey, the only other piscine IL-8 gene that has been cloned. Flounder IL-8 transcripts were detected in the head-kidney and spleen of LPS-injected flounder and leukocytes stimulated with LPS. It was not detected in the muscle or liver of LPS-injected flounder, tissues taken from non-stimulated flounder and non-stimulated leukocytes.

Amino Acid Sequence↗
PubMed2001

Genetic alterations in gallbladder adenoma, dysplasia and carcinoma.

Adenoma and dysplasia in the gallbladder (GB) have been reported as precancerous lesions, but the genetic evidence of this is not clearly defined. The purpose of this study was to analyze the frequencies of K-ras, p53, and p16 gene mutations, of microsatellite instability (MI) and of loss of heterozygosity (LOH) in GB cancer, dysplasia, and adenoma. Tissues from 15 GB cancers, five dysplasias around cancerous tumors, and three adenomas were collected prospectively. The mutation rates of K-ras, p53, and p16 were 20.0, 35.7, and 30.7%, respectively, in GB cancers. However, no mutations were found in dysplasia or adenoma. Reduced staining for p16 was seen in 23% of carcinomas. All of the GB carcinomas and four out of five (80%) of the dysplasias showed LOH in a minimum of one locus, but one out of three (33%) cases of adenoma displayed LOH in only one locus. All of the loci of LOH in the dysplasias, except one, showed the same patterns of allelic loss as the adjacent carcinomas. Only one dysplasia showed multiple MI. In conclusion, multiple LOH may be associated with the development of dysplasia and the malignant transformation of GB carcinoma. Gene alterations of K-ras, p53, and p16 are important steps in the malignant changes of dysplasia. However, MI seems to have only a limited role in GB cancer development.

Adenoma↗
PubMed2001

CDNA for an immune response gene encoding low molecular weight polypeptide from flounder, Paralichthys olivaceus.

The cDNA for an immune response gene encoding the low molecular weight polypeptide (LMP7) was cloned and sequenced from a flounder (Paralichthys olivaceus) leukocyte cDNA library. The cDNA clone was 1,160 bp, and composed of an open reading frame of 822 bp that corresponded to a protein of 273 amino acid residues with a calculated mass of 30.5 kDa. The ScanProsite search indicated that the deduced amino acid sequence from the flounder LMP7 contains a proteasome beta-type subunit signature, which is well conserved during evolution. The sequence shares a high degree of identity with other LMP7 sequences varying from a 66% identity with zebra fish (Danio renio) to a 57% identity with the African clawed frog (Xenopus laevis), which was confirmed from a phylogenetic tree. A reverse transcription-polymerase chain reaction (RT-PCR) was used to determine tissue specificity, and the expression of LMP7 was detected from the liver, kidney, leukocyte, and spleen of the flounder.

Amino Acid Sequence↗
PubMed2001

The application of comparative genomic hybridization as an additional tool in the chromosome analysis of acute myeloid leukemia and myelodysplastic syndromes.

In acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) there are frequently complex karyotypes with multiple structurally altered chromosomes, many of which are marker chromosomes of unknown origin. The aim of this study was to apply comparative genomic hybridization (CGH) to cases of AML or MDS in transformation submitted for routine cytogenetic analysis to investigate whether this approach would yield any further information and, if possible, to predict which cases would benefit from CGH analysis. Nineteen cases with AML or MDS in transformation were analyzed. CGH revealed nine cases with gains or losses of chromosomal material. In six of these cases the chromosomal location of this material was not apparent from cytogenetic analysis especially when multiple markers were present. By using fluorescence in situ hybridization (FISH) with specific libraries for the chromosome regions that showed discordance between CGH and conventional cytogenetics, we were able to identify the chromosome location of material within the karyotype. In this group of six patients, four cases of an unbalanced translocation involving regions of chromosomes 5 and 17 were characterized. Three of these cases had additional abnormalities, including two cases with regions of amplification in which oncogenes are located (MYC, MLL) and one case with a dic(7;21)(p10;p10). In all six cases it was possible to characterize complex chromosomal aberrations such as derivative chromosomes, marker chromosomes, and ring chromosomes. This study demonstrates that CGH can detect true gain and loss of critical chromosome regions more accurately than conventional karyotyping in cases with very complex karyotypes, and can thus prove useful in predicting prognosis and pinpointing areas of the genome that require further study. Also, CGH can be a useful technique to identify the origin of marker chromosomes, and it can assist in choice of probes for confirmatory FISH, when there is no clue provided from the analysis of G-banded chromosomes.

Acute Disease↗
PubMed2001

Primary structures and chain dominance of anti-DNA antibodies.

Using several anti-DNA autoantibodies, we analyzed the relative involvement of heavy and light chains in their interactions with DNA. We previously obtained eight hybridomas producing monoclonal anti-DNA autoantibodies by fusing spleen cells from an MRL-lpr/lpr mouse with myeloma cells. The chain dominance was analyzed by UV cross-linking experiments, in which the antibodies were covalently cross-linked with radioisotope-labeled oligonucleotides by short-wavelength UV-light, and the cross-linked H and L chains were analyzed by SDS-PAGE and densitometric scanning. Among these, three were found to be heavy chain dominant antibodies in which heavy chains are dominantly involved in DNA binding. The other five were co-dominant antibodies in which both heavy and light chains are involved in DNA binding. To determine the factor(s) that can explain the chain dominance in DNA binding, we determined the amino acid sequences of the variable regions of both heavy (VH) and light (VL) chains of all eight monoclonal antibodies. By analyzing the data, we were able to draw the following conclusions: (1) The arginine residues are found in the CDR3 regions of both VH and VL of the co-dominant antibodies; whereas, the same residues are found only in the CDR3s of VH, but not in VL, of the heavy chain dominant antibodies. (2) The net charges of the V regions affect the chain dominance. From the results of this study it is suggested that the presence of arginine residue in CDR3 is a critical factor in determining chain-dominance, as well as DNA binding of anti-DNA antibodies in general.

Amino Acid Sequence↗
PubMed2001

Is it necessary to resect the diseased esophagus in performing reconstruction for corrosive esophageal stricture?

OBJECTIVE: The incidence of carcinoma of the esophagus among patients with chronic esophageal stricture caused by ingestion of corrosive agents is reported to be significantly higher than that of the general population. The question of whether or not a resection of the diseased esophagus should be included in the surgical reconstruction procedure of the undilatable esophageal stricture continues to be a controversial. METHODS: During the 12 year period from 1988 to 1999, a total of 54 consecutive patients with caustic stricture of the esophagus were treated in our department. We retrospectively reviewed these cases and analyzed the incidence of cicatrical carcinoma among the patients and the risk of esophagectomy according to the procedures performed. RESULTS: We found seven cases of esophageal cancer among these patients. There was no significant increase in mortality or morbidity related to esophagectomy. CONCLUSIONS: Considering the high incidence of cicatrical carcinoma from the stricture sites as well as the possible chance of hidden malignancy, we concluded that the simultaneous resection of the esophagus with reconstruction for patients with chronic intractable caustic stricture would give the patients a better probability of being completely cured of the disease.

Adult↗
PubMed2001

Isolation and characterization of antioxidative peptides from gelatin hydrolysate of Alaska pollack skin.

Gelatin extracted from Alaska pollack skin was hydrolyzed with serial digestions in the order of Alcalase, Pronase E, and collagenase using a three-step recycling membrane reactor. The fraction from the second step, which was hydrolyzed with Pronase E, was composed of peptides ranging from 1.5 to 4.5 kDa and showed high antioxidative activity. Two different peptides showing strong antioxidative activity were isolated from the hydrolysate using consecutive chromatographic methods including gel filtration on a Sephadex G-25 column, ion-exchange chromatography on a SP-Sephadex C-25 column, and high-performance liquid chromatography on an ODS column. The isolated peptides, P1 and P2, were composed of 13 and 16 amino acid residues, respectively; and both peptides contained a Gly residue at the C-terminus and the repeating motif Gly-Pro-Hyp. The antioxidative activities of the purified peptides were measured using the thiobarbituric acid method, and the cell viability was measured with MTT assay. The results showed that P2 had potent antioxidative activity on peroxidation of linoleic acid. Moreover, the cell viability of cultured liver cells was significantly enhanced by addition of the peptide. These results indicate that the purified peptide, P2, from gelatin hydrolysate of Alaska pollack skin is a natural antioxidant which has potent antioxidative activity.

Animals↗
PubMed2001

Loss in 3p and 4p and gain of 3q are concomitant aberrations in squamous cell carcinoma of the vulva.

Neoplasm of the vulva is a rare malignancy accounting for <5% of all female genital-tract cancer. However, in recent years the incidence of vulva intraepithelial neoplasia, known to serve as a precursor to carcinoma, has increased in young women generating considerable interest in its pathogenesis. Genetic changes at the molecular level in precursor or invasive vulvar tumors are not well investigated, and DNA copy number changes have not been reported until now. We used comparative genomic hybridization (CGH) to analyze genetic alterations in 10 primary invasive squamous cell carcinomas of the vulva. Chromosomal aberrations were identified in 8/10 cases. The most frequent chromosomal losses were 4p13-pter (five cases), 3p (four cases), and 5q (two cases), and less frequent losses were detected at 6q, 11q, and 13q (one case each). The most frequent chromosomal gains were 3q (four cases) and 8p (three cases), and less frequent gains were found in 9p, 14, 17, and 20q (one case each). The pattern of chromosomal imbalance in vulvar cancer detected by CGH was revealed to be very similar to that in cervical cancers, despite regional differences in their prevalence. These results suggest that the pathogenic pathways in vulvar and cervical carcinomas may be similar and that the genetic background may be common to these two squamous cell carcinomas.

Adult↗
PubMed2001

Replication and cytolysis of an E1B-attenuated adenovirus in drug-resistant ovarian tumour cells is associated with reduced apoptosis.

Therapeutic approaches which are effective in tumour cells resistant to conventional chemotherapy would be of value. An E1B 55 kDa-deleted adenovirus (ONYX-015) induces lysis in cells with mutant p53, although the specificity of these observations for different cell types is unclear. We have used a matched set of drug-resistant human ovarian tumour cell lines to examine the potential of ONYX-015 for preferential replication and lysis of drug-resistant ovarian tumour cells with documented alterations in p53 function. Marked preferential replication of ONYX-015 is observed after infection of mutant p53 transfectant and cisplatin-resistant derivatives, compared to the wild-type p53 expressing parental A2780 line. Infection causes increased cytopathic effects in vitro and inhibition of tumour growth in vivo of the drug-resistant derivatives, but not the parental line. In apparent contrast, increased apoptosis and reduced clonogenic survival is induced by ONYX-015 infection of the chemosensitive parental cell line. ONYX-015 induces increased pro-apoptotic BAX and reduced anti-apoptotic BCLX(L) in parental cells, but not in the resistant derivative A2780/cp70. We propose that induction of apoptosis is one factor which prevents ONYX-015 spread and cytolysis after infection of chemosensitive cells, while it is the failure to engage apoptosis in drug-resistant cells that allows preferential viral replication, spread and cytolysis.

Adenoviridae↗
PubMed2001

Inhibitory activity for chitin synthase II from Saccharomyces cerevisiae by tannins and related compounds.

In the course of search for potent inhibitors of chitin synthase II from natural resources, seven tannins and related compounds were isolated from the aerial part of Euphorbia pekinensis and identified as gallic acid (1), methyl gallate (2), 3-O-galloyl-(-)-shikimic acid (3), corilagin (4), geraniin (5), quercetin-3-O-(2"-O-galloyl)-beta-D-glucoside (6), and kaempferol-3-O-(2"-O-galloyl)-beta-D-glucoside (7). These and nine related compounds, (-)-quinic acid (8), (-)-shikimic acid (9), ellagic acid (10), kaempferol (11), quercetin (12), quercitrin (13), rutin (14), quercetin-3-O-(2"-O-galloyl)-beta-D-rutinoside (15) and 1,3,4,6-tetra-O-galloyl-beta-D-glucose (16), were evaluated for the inhibitory activity against chitin synthase II and III. They inhibited chitin synthase II with IC(50) values of 18-206 microM, except for two organic acids, (-)-quinic acid (8) and (-)-shikimic acid (9). Among them, 3-O-galloyl-(-)-shikimic acid (3) was the most potent inhibitor against chitin synthase II of Saccharomyces cerevisiae with an IC(50) value of 18 microM. The inhibition appears to be selective for chitin synthase II, as they did not appreciably inhibit chitin synthase III.

Antifungal Agents↗
PubMed2001

Up-regulation of MUC5AC mRNA expression in endotoxin-induced otitis media.

We investigated the expression levels of MUC5AC in endotoxin-induced otitis media with effusion (OME) in the rat using competitive polymerase chain reaction (PCR) and the morphology of middle ear mucosa using transmission electron microscopy (TEM). Experimental OME in the rat was induced after middle ear instillation of Escherichia coli lipopolysaccharides (LPS). Middle ear mucosa were obtained at 0 h, 12 h, Day 1, Day 3, Day 7 and Day 14 and reverse transcriptase (RT)-PCRs were then performed for the identification of MUC1, MUC2, MUC5AC and submandibular mucin 1 expression, followed by competitive PCRs for MUC5AC and beta2-microglobulin expression. Normal middle ear mucosa revealed no expression of mucin genes, whereas endotoxin upregulated the expression of MUC5AC mRNA between 12 h and Day 7, with maximal expression at Days 1 and 3. Middle ears treated three times with LPS upregulated more MUC5AC mRNA expression, by a factor of approximately 3.5, than those 1 day after one instillation. On TEM, dark granulated cells were observed at Day 3 after endotoxin instillation, but mixed granulated cells were seen on the ears treated three times with LPS. These results suggest that MUC5AC could be one of the major mucin genes in the middle ear mucosa related to otitis media.

Animals↗
PubMed2001

Amplification at 9p in cervical carcinoma by comparative genomic hybridization.

DNA copy number changes were studied by comparative genomic hybridization on 10 tumor specimens of squamous cell carcinoma of cervix obtained from Korean patients. DNA was extracted from paraffin-embedded sections after removal of non-malignant cells by microdissection technique. Copy number changes were found in 8/10 tumors. The most frequent changes were chromosome 19 gains (n=6) and losses on chromosomes 4 (n=4), 5 (n=3), and 3p (n=3). A novel finding was amplification in chromosome arm 9p21-pter in 2 cases. Gains in 1, 3q, 5p, 6p, 8q, 16p, 17, and 20q and losses at 2q, 6q, 8p, 9q, 10p, 11, 13, 16q, and 18q were observed in at least one of the cases.

Adult↗
PubMed2001

Extraovarian granulosa cell tumor.

A 54-year-old woman was admitted to our hospital complaining of postcoital bleeding. Sonography of the abdomen showed a 8.2 x 8.9 cm-sized solid heterogeneous mass occupying the cul-de-sac, which appeared to be in no way connected with the ovary. On exploratory laparotomy, the tumor mass protruded from the posterolateral retroperitoneum of the pelvic cavity and severely replaced the uterus and adnexa with the outer surface being grossly intact. It grossly measured 10 cm in maximal diameter. The histologic features closely resembled those of ovarian granulosa cell tumor. The primary extraovarian granulosa cell tumor is extremely rare such that in the English literature only 7 cases have been reported to date. Of those granulosa cell tumors are especially rare and only two cases have been reported to arise from retroperitoneum. We herein present a case of retroperitoneal granulosa cell tumor with special regard to differential diagnosis from other solid tumors with similar histology.

Diagnosis, Differential↗
PubMed2000

Y chromosome microdeletions in idiopathic azoospermia and non-mosaic type of Klinefelter syndrome.

The objective of this study was to elucidate the cause of the spermatogenic defect in idiopathic azoospermia and non-mosaic type of Klinefelter syndrome. Genomic DNAs from 9 cases of Korean idiopathic azoospermia and 6 of Korean non-mosaic type of Klinefelter syndrome were used for the detection of Y chromosome microdeletions by polymerase chain reaction using 60 primers. Microdeletions of the Y chromosome were found in 1 of 9 (11.1%) patients with idiopathic azoospermia, whereas none was deleted in non-mosaic type of Klinefelter syndrome. This result suggests that Y chromosome microdeletions could be one of the etiologic factors in idiopathic azoospermia.

Gene Dosage↗
PubMed2000

Structural characterization of beta-D-(1 --> 3, 1 --> 6)-linked glucans using NMR spectroscopy.

Nondestructive structural analysis of a series of beta-D-(1 --> 3, 1 --> 6)-linked glucans (laminaran, curdlan, yeast glucan, scleroglucan, etc.) was performed using two-dimensional NMR spectroscopy. The relative ratios of H-1 at different AGUs provided the information about DPn and DB. The alpha-, and beta-anomeric protons on reducing terminals were assigned at 5.02 to approximately 5.03 ppm (J 3.6 to approximately 3.7 Hz), and 4.42 to approximately 4.43 ppm (J 7.6 to approximately 7.9 Hz), respectively, whereas the H-1 protons of internal AGUs and beta-(1 --> 6)-branched AGUs appeared at 4.56 to approximately 4.59 ppm (J 7.6 to approximately 7.8 Hz), and 4.26 to approximately 4.28 ppm (J 7.6 to approximately 10.6 Hz), respectively, in a mixed solvent of 6:1 Me2SO-d6-D2O at 80 degrees C. In the solvent, the OH peaks were eliminated from the spectra allowing the H-1 protons to appear clearly. In addition, the nonreducing terminal H-1 and H-1 at the AGU next to reducing terminal could be assigned at 4.45 to approximately 4.46 ppm (J 7.8 to approximately 7.9 Hz), and 4.51 to approximately 4.53 ppm (J 7.8 Hz), respectively. The DPn of the laminaran was 33 (polydispersity 1.12) and the DB was 0.07. The number of glucosyl units in the side chain of laminaran is more than one. The DPn and DB of the water-insoluble yeast glucan were 228 and 0.003, respectively. However the DPn of water soluble yeast glucan phosphate and curdlan was changed upon the number of freeze-drying processes and the content of water in the mixed solvent, respectively. And the DB of those were calculated as 0.02 and 0, respectively. The DB of scleroglucan was precisely calculated as 0.33, compared with the previously reported data. The H-1s at different AGUs of the various beta-D-(1 --> 3, 1 --> 6)-linked glucans having different DB can be exactly assigned by their chemical shifts in the mixed solvent system. This NMR analysis can be effectively used to determine the DP and DB of polysaccharides in a simple and non-destructive manner.

Carbohydrate Conformation↗
PubMed2000

Expression of cyclin E in placentas with hydropic change and gestational trophoblastic diseases: implications for the malignant transformation of trophoblasts.

BACKGROUND: Although much is known about the morphologic, cytogenetic, and clinical characters of gestational trophoblastic diseases, little information has appeared concerning the parameters related to their persistence or neoplastic transformation. Cell cycle alterations in tumor tissue were examined in this study in light of obvious changes in the clinical behavior of malignant cells. There is an increasing body of evidence suggesting that the abnormal expression of cyclins is considered one of the most important events in malignant transformation of various human cancers. Among these cell cycle regulators, the role of cyclin E in the neoplastic transformation of trophoblast populations has been poorly defined. METHODS: Using formalin fixed, paraffin embedded trophoblastic tissues, the authors investigated the expression of cyclin E by immunohistochemistry in placentas with hydropic change and gestational trophoblastic diseases. The specimens examined included tissue from 29 patients with complete hydatidiform mole, 18 patients with partial hydatidiform mole, and 6 patients with choriocarcinoma after term pregnancy or abortion. The authors also studied four cases of hydropic abortion. RESULTS: The cyclin E indexes (CEI) were as follows: 25.7% +/- 6.2% for hydropic change, 35.3% +/- 12.7% for triploid partial moles, 42.2% +/- 13.1% for diploid/tetraploid complete moles, and 63.6% +/- 9.5% for choriocarcinomas. There was a significant difference in CEI between placentas with hydropic change and partial mole (P = 0.04) and placentas with hydropic change and complete mole (P = 0.003). Choriocarcinomas had significantly higher cyclin E expression compared with placentas, partial moles, and complete moles, respectively. A significant correlation between the expression of cyclin E and S-phase fraction was observed in gestational trophoblastic diseases (rank correlation coefficient = 0.45, P < 0. 05). The relation between cyclin E expression and proliferation was abrogated in placentas with hydropic change, suggesting that cyclin E up-regulation represents a genuine aberration. CONCLUSIONS: The results of this study were consistent with the concept that cyclin E overaccumulation may play an important role in the uncontrolled proliferation and neoplastic transformation of trophoblasts.

Cell Cycle↗
PubMed2000

Effects of Polycomb group mutations on the expression of Ultrabithorax in the Drosophila visceral mesoderm.

The Polycomb group (PcG) genes encode repressors of many developmental regulatory genes including homeotic genes and are known to act by modifying chromatin structure through complex formation. We describe how Ultrabithorax (Ubx) expression is affected by the PcG mutants in the visceral mesoderm. Mutant embryos of the genes extra sex combs (esc), Polycomb (Pc), additional sex combs (Asx) and pleiohomeotic (pho) were examined. In each mutation, Ubx was ectopically expressed outside of their normal domains along the anterior-posterior axis in the visceral mesoderm, which is consistent with the effect of PcG proteins repressing the homeotic genes in other tissues. All of these four PcG mutations exhibit complete or partial lack of midgut constriction. However, two thirds of esc mutant embryos did not show Ubx expression in parasegment 7 (PS7). Even in the embryos showing ectopic Ubx expression, the level of Ubx expression in the PcG mutations was weaker than that in normal embryos. We suggest that in PcG mutations the ectopic Ubx expression is caused by lack of PcG repressor proteins, while the weaker or lack of Ubx expression is due to the repression of Ubx by Abd-B protein which is ectopically expressed in PcG mutations as well.

Animals↗