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Biomedical subjects

J Y Choi

Publications and source records attributed to J Y Choi.

At least 91 records · Page 5Linked to original sources
PubMed2000

Groucho/TLE/R-esp proteins associate with the nuclear matrix and repress RUNX (CBF(alpha)/AML/PEBP2(alpha)) dependent activation of tissue-specific gene transcription.

The Runt related transcription factors RUNX (AML/CBF(alpha)/PEBP2(alpha)) are key regulators of hematopoiesis and osteogenesis. Using co-transfection experiments with four natural promoters, including those of the osteocalcin (OC), multi drug resistance (MDR), Rous Sarcoma Virus long terminal repeat (LTR), and bone sialoprotein (BSP) genes, we show that each of these promoters responds differently to the forced expression of RUNX proteins. However, the three RUNX subtypes (i.e. AML1, AML2, and AML3) regulate each promoter in a similar manner. Although the OC promoter is activated in a C terminus dependent manner, the MDR, LTR and BSP promoters are repressed by three distinct mechanisms, either independent of or involving the AML C terminus, or requiring only the conserved C-terminal pentapeptide VWRPY. Using yeast two hybrid assays we find that the C terminus of AML1 interacts with a Groucho/TLE/R-esp repressor protein. Co-expression assays reveal that TLE proteins repress AML dependent activation of OC gene transcription. Western and northern blot analyses suggest that TLE expression is regulated reciprocally with the levels of OC gene expression during osteoblast differentiation. Digital immunofluorescence microscopy results show that TLE1 and TLE2 are both associated with the nuclear matrix, and that a significant subset of each colocalizes with AML transcription factors. This co-localization of TLE and AML proteins is lost upon removing the C terminus of AML family members. Our findings indicate that suppression of AML-dependent gene activation by TLE proteins involves functional interactions with the C terminus of AML at the nuclear matrix in situ. Our data are consistent with the concept that the C termini of AML proteins support activation or repression of cell-type specific genes depending on the regulatory organization of the target promoter and subnuclear localization.

Animals↗
PubMed2000

Phylogenetic analysis of a retroposon family as represented on the human X chromosome.

SINE-R elements constitute a class of retroposons derived from the long terminal repeat (LTR) of the human endogenous retrovirus HERV-K family that are present in hominoid primates and active in the human genome. In an investigation of the X chromosome, we identified twenty-five SINE-R elements with between 89.6 and 97.7% homology with the SINE-R.C2 element that is human specific, originally identified in the gene for the C2 component of complement. SINE-R.C2 and a sequence HS307 that we previously identified in a region of Xq21.3 that has a recently created homology with a 4 Mb block in Yp11.2 are amongst the group of elements that have diverged furthest from the parent HERV-K10 sequence. The sequence on the X chromosome resemble those that we previously described on chromosomes 7 and 17 and the Y chromosome, with a similar range of variation. Phylogenetic analysis from the retroposon family including those of African great apes using the neighbor-joining method suggests that the SINE-R retroposon family have evolved independently during primate evolution. Further investigation of SINE-R elements on the sex chromosomes, particularly in recently created regions of X-Y homology, may cast light on the timing of the retroposition process and its possible relevance to recent evolutionary change.

Animals↗
PubMed2000

Mutations of hepatitis C virus 1b NS5A 2209-2248 amino acid sequence is not a predictive factor for response to interferon-alpha therapy and development of hepatocellular carcinoma.

Genetic changes between codons 2209 and 2248 of NS5A of genotype 1b hepatitis C virus (HCV-1b) have been reported to be associated with the sensitivity to interferon-alpha (IFN-alpha). The present study was performed to analyze such relationship in Korean patients with chronic hepatitis C and HCV-1b (n=19), including 12 chronic hepatitis C patients treated with IFN-alpha, 3 chronic hepatitis C patients without treatment as controls, and 4 patients with hepatocellular carcinoma (HCC). Two serum samples, before and after the treatment, were analyzed for the mutations by reverse transcription-polymerase chain reaction, cloning and sequencing. The mutations were identified in 32% (6/19), including five intermediate type (1-3 mutations) and one mutant type (4 or more). In 12 patients treated with IFN-alpha, the number of amino acid substitutions in NS5A2209-2248 was not associated with outcome of the treatment. Two HCV isolates with NS5A2209-2248 mutations from HCC patients were intermediate type. These results do not support that the NS5A2209-2248 determines interferon sensitivity of HCV-1b and that the mutations is associated with development of HCC.

Adult↗
PubMed2000

A case of Goodpasture's syndrome with massive pulmonary hemorrhage.

We present a typical case of Goodpasture's syndrome with massive pulmonary hemorrhage and acute deterioration of renal function. A 20-year-old male was admitted due to severe azotemia (blood urea nitrogen 214.7 mg/dL, serum creatinine 30.2 mg/dL) and was treated with emergency hemodialysis. On the 4th hospital day, a sudden onset of pulmonary hemorrhage developed. The circulating level of anti-glomerular basement membrane antibody was then elevated highly, and the kidney biopsy showed crescentic glomerulonephritis and linear deposition of IgG along the glomerular capillary. The patient was treated with intravenous high dose-steroid, oral cyclophosphamide and plasma exchanges. The pulmonary hemorrhage improved with the therapy, however, his renal function did not improve. He is currently on a regular schedule of hemodialysis.

Adult↗
PubMed2000

Improved detection of individual nodal involvement in squamous cell carcinoma of the esophagus by FDG PET.

UNLABELLED: Because both the number and location of metastatic lymph nodes and the N stage influence survival in esophageal cancer, accurate noninvasive evaluation of individual lymph node groups for the presence of metastasis is essential for therapeutic planning. Therefore, we investigated the accuracy of FDG PET for evaluating individual lymph groups in esophageal cancer patients and compared the results with those of CT and endoscopic sonography (ES). METHODS: Sixty-one consecutive patients with histologically proven primary esophageal carcinoma were studied prospectively with FDG PET. Thirteen patients who were treated nonsurgically were excluded from data analysis. The remaining 48 patients underwent esophagectomy and lymph node dissection. All 48 patients underwent CT scanning, including the lower neck, thorax, and upper abdomen, with intravenous administration of contrast medium. ES was performed in 45 of the patients but was incomplete in 12 patients because of esophageal stenosis. The accuracies of FDG PET, CT, and ES were compared with histologic findings. RESULTS: During surgery, a total of 382 lymph node groups were dissected in 48 patients, of which 100 node groups in 32 patients were malignant on histologic examination. For assessing metastasis to individual groups, FDG PET showed 57% sensitivity, 97% specificity, and 86% accuracy, whereas CT showed 18% sensitivity (P < 0.0001), 99% specificity (P = 0.033), and 78% accuracy (P = 0.003). For N staging, FDG PET was correct in 83% (40/48) of the patients, whereas CT and ES were correct in 60% (29/48; P = 0.006) and 58% (26/45; P = 0.003), respectively. CONCLUSION: FDG PET is more accurate than is CT or ES for evaluating metastasis to individual lymph node groups and for N staging in esophageal cancer and thus may be helpful in determining the therapeutic plan.

Aged↗
PubMed2000

Vasoconstrictive eicosanoid responses to extracorporeal circulation with or without an oxygenator in fetal lambs.

INTRODUCTION: This study measured levels of vasoconstrictive eicosanoids during ovine fetal cardiac bypass and compared the measurements between two groups: (1) a group in which the placenta functioned as the only source of oxygen supply during the bypass (the placenta group), and (2) a group in which an artificial oxygenator, instead of the placenta, was included in the bypass circuit (the oxygenator group). MATERIALS AND METHODS: A total of 16 fetal lambs were randomly assigned into either the oxygenator group or the placenta group. Following anesthesia, the fetal cardiac bypass procedure was performed. The placenta group used a centrifugal pump as the pumping device without an oxygenator during the bypass. The bypass circuit in the oxygenator group consisted of a roller pump and a membrane oxygenator. The fetal cardiac bypass procedure was performed for 30 minutes at normothermia in both groups. For the measurements of thromboxane B2(TXB2) and prostaglandin E2 (PGE2), blood samples were taken before the bypass, at 5 minutes, 15 minutes, and 30 minutes after the start of cardiac bypass, and at 15 minutes after weaning from the bypass. TXB2 and PGE2 levels were determined by radioimmunoassay with PGE2(125I) and TXB2(125I) assay systems. Hemodynamic observations and arterial blood gas analyses were done every 10 minutes. RESULTS: The mean arterial pressure and heart rate ranged from 69.8 to 82.6 mmHg and 169 to 182/min during the bypass in the oxygenator group, and from 14.4 to 44.7 mmHg and 64.3 to 75/min in the placenta group. Arterial blood gas analysis showed severe hypercapnia and hypoxemia with acidosis during and after the bypass in the placenta group. Bypass flow rates were maintained at 140.3-164.0 ml/kg/min in the oxygenator group, while flow rates were suboptimal (74.3-97.0 ml/kg/min) in the placenta group. There were no statistically significant differences in PGE2 concentrations before, during, or after bypass, although the placenta group displayed a tendency to higher measurements during bypass, compared to the oxygenator group. The placenta group also showed higher TXB2 measurements than the oxygenator group during the bypass (p = 0.0457). CONCLUSIONS: We have demonstrated increase measurements of PGE2 and TXB2 in the placenta group when compared with the oxygenator group in an ovine fetal cardiac bypass model, although the PGE2 difference failed to reach statistical significance.

Animals↗
PubMed2000

Extra-articular pigmented villonodular synovitis of the temporomandibular joint: case report and review of the literature.

Pigmented villonodular synovitis (PVNS) is a benign proliferative disorder of the synovial tissue, that usually affects the knee, ankle and other major joints. Involvement of the temporomandibular joint is, however, very rare. We describe a new case of recurrent PVNS arising from the temporomandibular joint that was classified as diffuse extra-articular type and was successfully treated surgically. The etiology and clinical features of PVNS are discussed and the previously reported cases in the literature are reviewed.

Bone Transplantation↗
PubMed1999

Crystal structure of the nuclear matrix targeting signal of the transcription factor acute myelogenous leukemia-1/polyoma enhancer-binding protein 2alphaB/core binding factor alpha2.

Transcription factors of the acute myelogenous leukemia (AML)/polyoma enhancer-binding protein (PEBP2alpha)/core-binding factor alpha (CBFA) class are key transactivators of tissue-specific genes of the hematopoietic and bone lineages. AML-1/PEBP2alphaB/CBFA2 proteins participating in transcription are associated with the nuclear matrix. This association is solely dependent on a highly conserved C-terminal protein segment, designated the nuclear matrix targeting signal (NMTS). The NMTS of AML-1 is physically distinct from the nuclear localization signal, operates autonomously, and supports transactivation. Our data indicate that the related AML-3 and AML-2 proteins are also targeted to the nuclear matrix in situ by analogous C-terminal domains. Here we report the first crystal structure of an NMTS in an AML-1 segment fused to glutathione S-transferase. The model of the NMTS consists of two loops connected by a flexible U-shaped peptide chain.

Amino Acid Sequence↗
PubMed1999

TGF-beta-induced cell-cycle arrest through the p21(WAF1/CIP1)-G1 cyclin/Cdks-p130 pathway in gastric-carcinoma cells.

Transforming growth factor-beta1 (TGF-beta) inhibits cell-cycle progression of many types of cells by arresting them in G(1)/S phase through inhibition of the active cyclin-Cdk complexes that lead to inhibition of Rb phosphorylation. In gastric-cancer cells, SNU16, TGF-beta treatment induced enhanced expression of p21(WAF1/CIP1) (p21), which inhibited the kinase activity of cyclin-D- and cyclin-E-associated Cdks and blocked p130 phosphorylation. TGF-beta also enhanced the stability of p130, suggesting that hypophosphorylation of p130 and increased stability of p130 contribute to p130-mediated G(1) arrest in gastric-cancer cells. Our results demonstrate that p21 and p130 are major downstream targets of TGF-beta in gastric-cancer cells and that a p21-G(1) cyclin/Cdks-p130/E2F pathway mediates growth inhibition by TGF-beta in these cells.

Carcinoma↗
PubMed1999

Development of a novel expression vector system using Spodoptera exigua nucleopolyhedrovirus.

To develop a novel Spodoptera exigua nucleopolyhedrovirus (SeNPV) expression vector system, we examined characteristics of the SeNPV polyhedrin expression in S. exigua cells (Se301). While the extracellular virus titer of SeNPV was 100-fold lower than that of Autographa californica nucleopolyhedrovirus (AcNPV), the levels of polyhedral inclusion body (PIB) formation and polyhedrin expression were higher in SeNPV. To investigate foreign gene expression under the control of the polyhedrin promoter, polyhedrin-based transfer vector pSeKSK2 was constructed, and then recombinant virus SeK1-LacZ was constructed by inserting E. coli lacZ gene as a reporter gene into a genomic DNA of SeNPV using this transfer vector. The beta-Galactosidase activity of SeK1-LacZ in Se301 was about 1.3 times higher than that of BacPAK6. Thus, the SeNPV expression vector system constructed in this study would be very useful in the expression of foreign proteins, specifically for the enhancement of the pesticidal properties of SeNPV by inserting pesticidal genes.

Animals↗
PubMed1999

Identification of cDNAs for Sox-4, an HMG-Box protein, and a novel human homolog of yeast splicing factor SSF-1 differentially regulated during apoptosis induced by prostaglandin A2/delta12-PGJ2 in Hep3B cells.

We have examined specific genes whose expression is altered during apoptosis induced by prostaglandin (PG)A2 and Delta12-PGJ2 in human hepatocellular carcinoma Hep3B cells. Using mRNA differential display, we have identified two genes: one is specifically up-regulated and encodes for human Sox-4 (Sry-HMG box gene) and the other is significantly down-regulated and is the human homolog of yeast Ssf-1, a novel splicing factor. Northern blot analysis confirmed their differential expressions. Interestingly, Sox-4 was highly expressed in subcutaneous tumors grown in nude mice as a xenograft from Hep3B cells. These results suggest that the expression of Sox-4 may be related to the apoptosis pathway leading to cell death as well as to tumorigenesis, and that Ssf-1 gene may serve as a negative regulator of PGA2/Delta12-PGJ2-mediated Hep3B cell apoptosis.

Animals↗
PubMed1999

Cystic fibrosis transmembrane conductance regulator regulates luminal Cl-/HCO3- exchange in mouse submandibular and pancreatic ducts.

We have demonstrated previously the regulation of Cl-/HCO3- exchange activity by the cystic fibrosis transmembrane conductance regulator (CFTR) in model systems of cells stably or transiently transfected with CFTR (Lee, M. G., Wigley, W. C., Zeng, W., Noel, L. E., Marino, C. R., Thomas, P. J., and Muallem, S. (1999) J. Biol. Chem. 274, 3414-3421). In the present work we examine the significance of this regulation in cells naturally expressing CFTR. These include the human colonic T84 cell line and the mouse submandibular gland and pancreatic ducts, tissues that express high levels of CFTR in the luminal membrane. As in heterologous expression systems, stimulation of T84 cells with forskolin increased the Cl-/HCO3- exchange activity independently of CFTR Cl- channel activity. Freshly isolated submandibular gland ducts from wild type mice showed variable Cl-/HCO3- exchange activity. Measurement of [Cl-]i revealed that this was largely the result of variable steady-state [Cl-]i. Membrane depolarization with 5 mM Ba2+ or 100 mM K+ increased and stabilized [Cl-]i. Under depolarized conditions wild type and DeltaF/DeltaF mice had comparable basal Cl-/HCO3- exchange activity. Notably, stimulation with forskolin increased Cl-/HCO3- exchange activity in submandibular gland ducts from wild type but not DeltaF/DeltaF mice. Microperfusion of the main pancreatic duct showed Cl-/HCO3- exchange activity in both the basolateral and luminal membranes. Stimulation of ducts from wild type animals with forskolin had no effect on basolateral but markedly stimulated luminal Cl-/HCO3- exchange activity. By contrast, forskolin had no effect on either basolateral or luminal Cl-/HCO3- exchange activity of ducts from DeltaF/DeltaF animals. We conclude that CFTR regulates luminal Cl-/HCO3- exchange activity in CFTR-expressing cells, and we discuss the possible physiological significance of these findings regarding cystic fibrosis.

Animals↗
PubMed1999

Transient upregulation of CBFA1 in response to bone morphogenetic protein-2 and transforming growth factor beta1 in C2C12 myogenic cells coincides with suppression of the myogenic phenotype but is not sufficient for osteoblast differentiation.

The bone morphogenetic protein (BMP)-2 is a potent osteoinductive signal, inducing bone formation in vivo and osteoblast differentiation from non-osseous cells in vitro. The runt domain-related protein Cbfa1/PEBP2alphaA/AML-3 is a critical component of bone formation in vivo and transcriptional regulator of osteoblast differentiation. To investigate the relationship between the extracellular BMP-2 signal, Cbfa1, and osteogenesis, we examined expression of Cbfa1 and osteoblastic genes during the BMP-2 induced osteogenic transdifferentiation of the myoblastic cell line C2C12. BMP-2 treatment completely blocked myotube formation and transiently induced expression of Cbfa1 and the bone-related homeodomain protein Msx-2 concomitant with loss of the myoblast phenotype. While induction of collagen type I and alkaline phosphatase (AP) expression coincided with Cbfa1 expression, Cbfa1 mRNA was strikingly downregulated at the onset of expression of osteopontin (OPN) and osteocalcin (OCN) genes, reflecting the mature osteoblast phenotype. TGF-beta1 treatment effectively suppressed myogenesis and induced Cbfa1 expression but was insufficient to support osteoblast differentiation reflected by the absence of ALP, OPN, and OCN. We addressed whether induction of Cbfa1 in response to BMP-2 results in the transcriptional activation of the OC promoter which contains three enhancer Cbfa1 elements. Transfection studies show BMP-2 suppresses OC promoter activity in C2C12, but not in osteoblastic ROS 17/2.8 cells. Maximal suppression of OC promoter activity in response to BMP-2 requires sequences in the proximal promoter (up to nt -365) and may occur independent of the three Cbfa sites. Taken together, our results demonstrate a dissociation of Cbfa1 expression from development of the osteoblast phenotype. Our findings suggest that Cbfal may function transiently to divert a committed myoblast to a potentially osteogenic cell. However, other factors induced by BMP-2 appear to be necessary for complete expression of the osteoblast phenotype.

Animals↗
PubMed1999

The Saccharomyces cerevisiae FAT1 gene encodes an acyl-CoA synthetase that is required for maintenance of very long chain fatty acid levels.

The Saccharomyces cerevisiae FAT1 gene appears to encode an acyl-CoA synthetase that is involved in the regulation of very long chain (C20-C26) fatty acids. Fat1p, has homology to a rat peroxisomal very long chain fatty acyl-CoA synthetase. Very long chain acyl-CoA synthetase activity is reduced in strains containing a disrupted FAT1 gene and is increased when FAT1 is expressed in insect cells under control of a baculovirus promoter. Fat1p accounts for approximately 90% of the C24-specific acyl-CoA synthetase activity in glucose-grown cells and approximately 66% of the total activity in cells grown under peroxisomal induction conditions. Localization of functional Fat1p:green fluorescent protein gene fusions and subcellular fractionation of C24 acyl-CoA synthetase activities indicate that the majority of Fat1p is located in internal cellular locations. Disruption of the FAT1 gene results in the accumulation of very long chain fatty acids in the sphingolipid and phospholipid fractions. This includes a 10-fold increase in C24 acids and a 6-fold increase in C22 acids. These abnormal accumulations are further increased by perturbation of very long chain fatty acid synthesis. Overexpression of Elo2p, a component of the fatty acid elongation system, in fat1Delta cells causes C20-C26 levels to rise to approximately 20% of the total fatty acids. These data suggest that Fat1p is involved in the maintenance of cellular very long chain fatty acid levels, apparently by facilitating beta-oxidation of excess intermediate length (C20-C24) species. Although fat1Delta cells were reported to grow poorly in oleic acid-supplemented medium when fatty acid synthase activity is inactivated by cerulenin, fatty acid import is not significantly affected in cells containing disrupted alleles of FAT1 and FAS2 (a subunit of fatty acid synthase). These results suggest that the primary cause of the growth-defective phenotype is a failure to metabolize the incorporated fatty acid rather than a defect in fatty acid transport. Certain fatty acyl-CoA synthetase activities, however, do appear to be essential for bulk fatty acid transport in Saccharomyces. Simultaneous disruption of FAA1 and FAA4, which encode long chain (C14-C18) fatty acyl-CoA synthetases, effectively blocks the import of long chain saturated and unsaturated fatty acids.

Amino Acid Sequence↗
PubMed1999

Involvement of specific calmodulin isoforms in salicylic acid-independent activation of plant disease resistance responses.

The Ca2+ signal is essential for the activation of plant defense responses, but downstream components of the signaling pathway are still poorly defined. Here we demonstrate that specific calmodulin (CaM) isoforms are activated by infection or pathogen-derived elicitors and participate in Ca2+-mediated induction of plant disease resistance responses. Soybean CaM (SCaM)-4 and SCaM-5 genes, which encode for divergent CaM isoforms, were induced within 30 min by a fungal elicitor or pathogen, whereas other SCaM genes encoding highly conserved CaM isoforms did not show such response. This pathogen-triggered induction of these genes specifically depended on the increase of intracellular Ca2+ level. Constitutive expression of SCaM-4 and SCaM-5 in transgenic tobacco plants triggered spontaneous induction of lesions and induces an array of systemic acquired resistance (SAR)-associated genes. Surprisingly, these transgenic plants have normal levels of endogenous salicylic acid (SA). Furthermore, coexpression of nahG gene did not block the induction of SAR-associated genes in these transgenic plants, indicating that SA is not involved in the SAR gene induction mediated by SCaM-4 or SCaM-5. The transgenic plants exhibit enhanced resistance to a wide spectrum of virulent and avirulent pathogens, including bacteria, fungi, and virus. These results suggest that specific CaM isoforms are components of a SA-independent signal transduction chain leading to disease resistance.

Calcium↗
PubMed1999

Maintenance of myoglobin concentration in human skeletal muscle after heavy resistance training.

The aim of this study was to determine the effects of 8 weeks of resistance training (RT) on the myoglobin concentration ([Mb]) in human skeletal muscle, and to compare the change in the [Mb] in two different RT protocols. The two types of protocol used were interval RT (IRT) of moderate to low intensity with a high number of repetitions and a short recovery time, and repetition RT (RRT) of high intensity with a low number of repetitions and a long recovery time. A group of 11 healthy male adults voluntarily participated in this study and were divided into IRT (n = 6) and RRT (n = 5) groups. Both training protocols were carried out twice a week for 8 weeks. At the completion of the training period, the one-repetition maximal force values and isometric force were increased significantly in all the subjects, by about 38.8% and 26.0%, respectively (P < 0.01). The muscle fibre composition was unchanged by the 8 weeks of training. The muscle fibre cross-sectional areas were increased significantly by both types of training in all fibre types (I, IIa and IIb, mean + 16.1 %, P < 0.05). The [Mb] showed no significant changes at the completion of the training [IRT from 4.63 (SD 0.63) to 4.48 (SD 0.72), RRT from 4.47 (SD 0.75) to 4.24 (SD 0.80) mg x g(-1) wet tissue] despite a significant decrease in citrate synthase activity [IRT from 5.27 (SD 1.45) to 4.49 (SD 1.48), RRT from 5.33 (SD 2.09) to 4.85 (SD 1.87) micromol x min(-1) x g(-1) wet tissue; P < 0.05] observed after both protocols. These results suggested that myoglobin and mitochondria enzymes were regulated by different mechanisms in response to either type of RT. Moreover, the maintained [Mb] in hypertrophied muscle should preserve oxygen transport from capillaries to mitochondria even when diffusion distance is increased.

Adult↗
PubMed1999

TT virus infection among blood donors and patients with non-B, non-C liver diseases in Korea.

BACKGROUND/AIMS: A novel virus, designated the TT virus (TTV), was isolated from the serum of a patient with posttransfusion hepatitis of unknown etiology, in Japan. Subsequently, TTV was suggested to be a causative agent in a proportion of cases with cryptogenic hepatitis in Japan. This study aimed to elucidate the significance of TTV infection in cases with cryptogenic liver disease in Korea, a neighbor of Japan. METHODS: The prevalence of TTV infection was studied in 120 patients with liver diseases, including 85 patients diagnosed as having non-B, non-C liver diseases. As controls, 220 blood donors were also examined. TTV DNA was detected by polymerase chain reaction, and the sequence was analyzed by phylogenetic analysis. RESULTS: Fourteen (14.0%) of 100 accepted blood donors, 23 (19.2%) of 120 rejected blood donors, and 15 (17.6%) of 85 patients with non-B, non-C liver diseases were positive for TTV DNA. The prevalences of TTV infection among these groups were not significantly different. Phylogenetic analysis suggested the existence of four major genotypes of TTV The proportions of each genotype among patients with non-B, non-C liver diseases were not different from those among accepted blood donors. CONCLUSIONS: TTV exists in Korea, but the prevalence among patients with non-B, non-C liver diseases was almost the same as that among blood donors. TTV may not be the main causative agent of cryptogenic liver disease in Korea. The relationship between non-B, non-C liver diseases and TTV genotype remains unclear, although TTV can be classified into four genotypes.

Adolescent↗