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Rha E, Park HJ, Kim MO, Chung YR, Lee CW, Kim JW. Expression of exo-polygalacturonases in Botrytis cinerea. FEMS Microbiol Lett 2001; 201:105-9. [PMID: 11445175 DOI: 10.1111/j.1574-6968.2001.tb10740.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The pathogenic fungus, Botrytis cinerea, causing gray mold disease in a variety of plant species, secretes at least four polygalacturonases (PGs), cell wall degrading enzymes. Among them, we prepared polyclonal antibody against purified 66-kDa exo-PG in rabbit. Immunoblot analysis revealed that the antibody recognized two exo-PGs, 66 kDa and 70 kDa in molecular mass, secreted from B. cinerea cultured in the medium containing citrus pectin as a carbon source. By immunohistochemical analysis, the expression of exo-PGs was identified in cucumber leaves inoculated with spores of B. cinerea. The exo-PGs were observed 9 h after inoculation, and the amount of exo-PGs increased with time in the leaves. The exo-PGs were induced by polygalacturonic acid as well as its monomer, galacturonic acid, in vitro. The expression of 66-kDa exo-PG (exo-PG I) increased with time of culture, while 70-kDa exo-PG (exo-PG II) was transiently expressed soon after the start of culture. Therefore, exo-PGs might play an important role in pathogenesis at an early stage of infection as well as in tissue maceration of host plant.
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Lee SH, Eom M, Lee SJ, Kim S, Park HJ, Park D. BetaPix-enhanced p38 activation by Cdc42/Rac/PAK/MKK3/6-mediated pathway. Implication in the regulation of membrane ruffling. J Biol Chem 2001; 276:25066-72. [PMID: 11309380 DOI: 10.1074/jbc.m010892200] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
betaPix (PAK-interacting exchange factor) is a recently identified guanine nucleotide exchange factor for Rho family small G protein Cdc42/Rac. The protein interacts with p21-activated protein kinase (PAK) through its SH3 domain. We examined the effect of betaPix on MAP kinase signaling and cytoskeletal rearrangement in NIH3T3 fibroblast cells. Overexpression of betaPix enhanced the activation of p38 in the absence of other stimuli and also induced translocation of p38 to the nucleus. This betaPix-induced p38 activation was blocked by coexpression of dominant-negative Cdc42/Rac or kinase-inactive PAK, indicating that the effect of betaPix on p38 is exerted through the Cdc42/Rac-PAK pathway and requires PAK kinase activity. The essential role of betaPix in growth factor-stimulated p38 activation was evidenced by the blocking of platelet-derived growth factor-induced p38 activation in the cells expressing betaPix SH3m (W43K) and betaPix DHm (L238R,L239R). In addition, SB203580, a p38 inhibitor, and kinase-inactive p38 (T180A,Y182F) blocked membrane ruffling induced by betaPix, suggesting that p38 might be involved in mediating betaPix-induced membrane ruffling. The results in this study suggest that betaPix might have a role in nuclear signaling, as well as in actin cytoskeleton regulation, and that some part of these cellular functions is possibly mediated by p38 MAP kinase.
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Kim DI, Kim MH, Lee SK, Seo DW, Choi WB, Lee SS, Park HJ, Joo YH, Yoo KS, Kim HJ, Min YI, Chol WB. Risk factors for recurrence of primary bile duct stones after endoscopic biliary sphincterotomy. Gastrointest Endosc 2001; 54:42-8. [PMID: 11427840 DOI: 10.1067/mge.2001.115335] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Endoscopic biliary sphincterotomy (EST) is a well-established procedure for bile duct stone extraction. Bile duct stones can be classified as primary or secondary. However, few data are available on the recurrence of primary and secondary bile duct stones after EST. Therefore risk factors for the recurrence of primary bile duct stones after EST were prospectively studied. METHODS Between 1991 and 1997, 61 patients underwent EST for primary bile duct stones. All met the following criteria: (1) previous cholecystectomy without bile duct exploration, (2) detection of bile duct stones at least 2 years after initial cholecystectomy. Mean follow-up was 2.2 years. Fourteen patients were lost to follow-up. The recurrence of primary bile duct stones was defined as the detection of bile duct stones no sooner than 6 months after complete clearance of primary bile duct stones. RESULTS The overall recurrence rate of primary bile duct stones was 21% (10 of 47). Two significant risk factors for recurrence were identified by multivariate analysis: (1) patients with a bile duct diameter of 13 mm or greater after stone removal had recurrences more frequently than those with a duct diameter of 13 mm or less, and (2) patients whose papilla was located on the inner rim or deep within a diverticulum, so that the papillary orifice was not visible endoscopically, had more frequent recurrences than patients with a papilla outside the diverticulum, or no peripapillary diverticulum. CONCLUSION The independent risk factors for recurrence of primary bile duct stones were sustained dilation of the bile duct even after complete removal of stones and location of the papilla on the inner rim or deep within a diverticulum.
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Park JI, Park HJ, Choi HS, Lee K, Lee WK, Chun SY. Gonadotropin regulation of NGFI-B messenger ribonucleic acid expression during ovarian follicle development in the rat. Endocrinology 2001; 142:3051-9. [PMID: 11416027 DOI: 10.1210/endo.142.7.8232] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
NGFI-B is an immediate-early gene that encodes an orphan nuclear receptor. The present study was designed to examine the localization and gonadotropin regulation of NGFI-B expression in the rat ovary. Northern blot analysis of ovaries obtained from prepubertal rats revealed the increased expression of NGFI-B during prepubertal development. Treatment of immature rats with PMSG, however, decreased ovarian NGFI-B expression. The major cell types expressing NGFI-B messenger RNA were thecal cells of follicles in different sizes. In contrast, treatment of PMSG-primed rats with human (h) CG resulted in the rapid and transient stimulation of ovarian NGFI-B messenger RNA, reaching a peak within 1 h. In situ hybridization analysis revealed that hCG treatment induced the expression of NGFI-B in granulosa cells of preovulatory follicles. Treatment of cultured preovulatory follicles in vitro with LH further confirmed the time- and dose-dependent stimulation of NGFI-B messenger RNA and protein. LH-stimulated NGFI-B expression in preovulatory follicles was abolished by alpha-amanitin, but was superinduced by cycloheximide. Furthermore, treatment of adult cycling rats with pentobarbital abolished NGFI-B expression on proestrus, and exogenous administration of hCG restored it, indicating the role of the preovulatory surge of LH in the stimulation of NGFI-B expression. These results demonstrate the cell type-specific expression and gonadotropin induction of NGFI-B in granulosa cells of preovulatory follicles and suggest a role for NGFI-B in the ovulatory process.
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Hahn SB, Park HJ, Kang HJ, Kang ES. Finger reconstruction with a free neurovascular wrap-around flap from the big toe. J Reconstr Microsurg 2001; 17:319-23. [PMID: 11499464 DOI: 10.1055/s-2001-16022] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
From 1983 to 1998, 16 cases of finger reconstruction with a free neurovascular wrap-around flap from the big toe were treated. Fourteen cases were successful, and two cases failed. The authors reviewed these cases on the average of about 38 months after surgery. Pinch power was 51 percent of the unaffected normal hand, and two-point discrimination was 7.6 mm. The mean resorption of the grafted bone was 13 percent in width and 9 percent in length. There were no complications such as fracture of the grafted bone, nonunion, and pulp dislodgement. This procedure provided length, stability, and adequate sensibility for a functional pinch and grasp. Sensory return to the wrap-around flap on the thumb was often greater than for the same area on the opposite foot. The donor site of the wrap-around flap was acceptable, both aesthetically and functionally, and allowed the wearing of open-toed shoes by young women. Finger reconstruction with a wrap-around flap from the big toe yielded excellent cosmetic and functional results in cases involving amputation at the level of the metacarpophalangealjoints or distal to it. In addition, this procedure was an excellent choice for treatment in cases involving avulsion injuries of the fingers and reconstruction of soft-tissue defects after tumor excision.
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Abstract
Ecthyma gangrenosum is a well recognized cutaneous manifestation of Pseudomonas aeruginosa infections in immunocompromised patients. Most cases of ecthyma gangrenosum have been associated with concomitant septicaemia. However, ecthyma gangrenosum rarely develops due to Ps. aeruginosa in the absence of bacteraemia. We report a rare case of a nonsepticaemic form of ecthyma gangrenosum presenting as a large solitary necrotic ulcer in a patient with acute myelogenous leukaemia. A culture from the lesion revealed the presence of Ps. aeruginosa, but the results of repeated blood cultures were negative. Histological examination revealed numerous tiny eosinophilic bacilli in the dermis and panniculus with Gram's stain.
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Abstract
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.
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Yoshioka H, Sugie K, Park HJ, Maeda H, Tsuda N, Kawakita K, Doke N. Induction of plant gp91 phox homolog by fungal cell wall, arachidonic acid, and salicylic acid in potato. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2001; 14:725-36. [PMID: 11386368 DOI: 10.1094/mpmi.2001.14.6.725] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The oxidative burst has been suggested to be a primary event responsible for triggering the cascade of defense responses in various plant species against infection with avirulent pathogens or pathogen-derived elicitors. The molecular mechanisms of rapid production of active oxygen species (AOS), however, are not well known. We isolated homologs of gp91 phox, a plasma membrane protein of the neutrophil NADPH oxidase, from a potato cDNA library. Molecular cloning of the cDNA showed that there are two isogenes, designated StrbohA and StrbohB, respectively. The RNA gel blot analyses showed that StrbohA was constitutively expressed at a low level, whereas StrbohB was induced by hyphal wall components (HWC elicitor) from Phytophthora infestans in potato tubers. Treatment of potato tubers with HWC elicitor caused a rapid but weak transient accumulation of H2O2 (phase I), followed by a massive oxidative burst 6 to 9 h after treatment (phase II). Diphenylene iodonium (DPI), an inhibitor of the neutrophil NADPH oxidase, blocked both bursts, whereas pretreatment of the protein synthesis inhibitor cycloheximide with the tuber abolished only the second burst. These results suggest that the expression of StrbohA and StrbohB contributes to phase I and II bursts, respectively. The same is true for arachidonic acid, a lipid component of P. infestans-stimulated biphasic oxidative burst, whereas an endogenous signaling molecule, salicylic acid, only induced a weak phase II burst. Both molecules induced the StrbohB expression, which is in agreement with the second burst. To characterize the signal transduction pathway leading to the oxidative burst, we examined the role of protein phosphorylation in HWC-stimulated StrbohB gene expression. K252a and staurosporine, two protein kinase inhibitors, blocked the transcript accumulation. Two inhibitors of extracellular Ca2+ movement, however, did not abolish the transcript accumulation of StrbohB, suggesting that certain calcium-independent protein kinases are involved in the process of StrbohB gene expression. Additionally, we examined a causal relationship between the oxidative burst and expression of defense genes induced by the HWC elicitor. The transcript accumulation of genes related to sesquiterpenoid phytoalexin synthesis (lubimin and rishitin) and phenylpropanoid pathway was inhibited slightly by the DPI treatment, suggesting that the oxidative burst is not essential to activate these genes. Interestingly, the concomitant presence of DPI with the elicitor resulted in an increase in lubimin accumulation and a decrease in rishitin accumulation. Because it is known that lubimin is metabolized into rishitin via oxylubimin, we propose that AOS mediates the synthesis of rishitin from lubimin.
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Abstract
BACKGROUND The arterial switch procedure has become the preferred procedure for the transposition of the great arteries (TGA) and Taussig-Bing anomaly. This analysis is intended to identify potential factors affecting survival in the current era. METHODS From 1986 to 1999, 201 consecutive patients underwent an arterial switch operation for TGA or Taussig-Bing anomaly. Multivariate analysis of perioperative variables was performed for operative morbidity/ mortality. Patients were separated into two groups. Phase 1 (n = 29) included patients before mid-1989 who underwent an open coronary reimplantation technique. Phase 2 (n = 172) included the patients undergoing a technique of reimplanting coronary buttons after neoaortic reconstruction. RESULTS The patient population included TGA with intact ventricular septum (58.7%, 118 of 201), with ventricular septal defect (31.3%, 61 of 201), and Taussig-Bing anomaly (10.0%, 22 of 201). Overall, early mortality was 9.5% (19 of 201) and there were five late deaths (2.7%). One-month, 1-year, and 5-year actuarial survival rates were 90.4%, 87.9%, and 87.9%, respectively. Reoperation rate for late pulmonary stenosis was 2.7% (5 of 182). The freedom from reoperation at 3 and 5 years was 97.5% and 93.3%, respectively. In the analysis by time period, the operative mortality declined from 27.6% (8 of 29) to 6.4% (11 of 172) (p = 0.002). Risk factors for operative death were coronary artery patterns (usual vs retropulmonary left coronary artery, p = 0.009) in phase 1 and preoperative instability in phase 2 (p = 0.002). CONCLUSIONS The arterial switch operation for TGA and Taussig-Bing anomaly has early low and late mortality and reoperation rates. Technical modifications in coronary reimplantation have minimized coronary artery pattern-related risks.
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Chung JP, Lee SJ, Park HJ, Lee KS, Chung JB, Lee SI, Kang JK. Are minimicrosphere pancrelipase capsules effective enough for the treatment of pancreatic steatorrhea? Am J Gastroenterol 2001; 96:1643-5. [PMID: 11374718 DOI: 10.1111/j.1572-0241.2001.03815.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Choi J, Huh K, Kim SH, Lee KT, Kwon SH, Park HJ. Toxicology of Kalopanax pictus extract and hematological effect of the isolated anti-rheumatoidal kalopanaxsaponin A on the Freunds complete adjuvant reagent-treated rat. Arch Pharm Res 2001; 24:119-25. [PMID: 11339631 DOI: 10.1007/bf02976479] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We have reported that kalopanaxsaponin A (KPS-A) isolated from Kalopanax pictus have anti-rheumatoidal activity in the rat treated with Freunds complete adjuvant (FCA) reagent. In addition, it has been also reported that KPS-A is a potent antioxidant in the rheumatoidal rat. This research was undertaken to examine whether the saponins of KPS-A and -I could adjust the abnormal lipid metabolisms and hematological changes in immunological diseases. KPS-A significantly inhibited the increases in both triglycerides and total proteins in addition to the decrease in total cholesterol induced by FCA reagent treatment. KPS-A treatment decreased the number of leucocytes elevated by FCA reagent treatment. Excess dose of the methanol extract produced no severe toxicity on the body weight, wet organ weights and hepatic functions. Since LD50 value of K. pictus methanol extract was shown to be 4,033 mg/kg, it could be estimated to be a safe agent for anti-rheumatoidal herbal medicines.
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Ohtsubo T, Igawa H, Saito T, Matsumoto H, Park HJ, Song CW, Kano E, Saito H. Acidic environment modifies heat- or radiation-induced apoptosis in human maxillary cancer cells. Int J Radiat Oncol Biol Phys 2001; 49:1391-8. [PMID: 11286847 DOI: 10.1016/s0360-3016(00)01590-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The effects of hyperthermia or irradiation on cell killing and induction of apoptosis were evaluated using human maxillary carcinoma IMC-3 cells and low pH (pH 6.8) adapted cells (IMC-3-pH). METHODS AND MATERIALS Cellular heat-sensitivity or radiosensitivity was determined using the clonogenic assay. Apoptosis was assessed on the basis of a flow cytometric determination of the DNA content, DNA fragmentation, and poly(ADP-ribose)polymerase cleavage. RESULTS When IMC-3 cells or IMC-3-pH cells were exposed to heat at 44 degrees C in pH 6.8 medium, an increase in thermosensitivity was observed compared with when the IMC-3 cells were exposed to heat at 44 degrees C in pH 7.4 medium. However, the selective reduction in survival was not observed after irradiation. In IMC-3 cells, apoptosis after heating at 44 degrees C for 60 min in pH 7.4 medium occurred earlier than that after 8 Gy irradiation, although both thermal and irradiated doses decreased the cell count to 10%. The degree of apoptosis after heating at pH 6.8 in IMC-3 cells or IMC-3-pH cells was greater than that at pH 7.4 in IMC-3 cells. However, the degree of apoptosis after 8 Gy irradiation at pH 6.8 in IMC-3 cells or IMC-3-pH cells was smaller than that at pH 7.4 in IMC-3 cells. CONCLUSION Hyperthermia treatment is more effective at inducing apoptosis than radiation is in tumors that contain a population of low pH adapted cells.
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Park K, Park HJ, Chun YM. Immunohistochemical study on proliferative activity of experimental cholesteatoma. Eur Arch Otorhinolaryngol 2001; 258:101-5. [PMID: 11374247 DOI: 10.1007/s004050100315] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we induced canal ligation cholesteatoma using Mongolian gerbils and investigated the hyperproliferative nature of canal ligation cholesteatoma by using an immunohistochemical technique with proliferation markers (cytokeratin 13/16, PCNA, EGFR, thrombomodulin). Canal ligation cholesteatoma using Mongolian gerbils had a hyperproliferative character in the suprabasal cell layer similar to human cholesteatomas. This result will provide a good morphological basis for future cholesteatoma animal research concerning the pathogenesis of cholesteatoma.
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Kim SB, Ahn IM, Park HJ, Park JS, Cho HJ, Gong G, Suh C, Lee JS, Kim WK, Kim SH. Growth inhibition and chemosensitivity of poorly differentiated human thyroid cancer cell line (NPA) transfected with p53 gene. Head Neck 2001; 23:223-9. [PMID: 11428453 DOI: 10.1002/1097-0347(200103)23:3<223::aid-hed1022>3.0.co;2-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND We investigated whether retroviral p53 transfection could enhance growth inhibition and chemosensitivity in a p53 mutant papillary thyroid cancer cell line (NPA). METHODS NPA cells were transfected with either LXSN/p53 or mock infection in the presence of Adriamycin. Gene expression was confirmed by western blotting. Nude mice were injected subcutaneously with NPA cells after transfection with either LXSN/p53 or mock infection on opposite sides, and the tumor growth was compared. RESULTS There was a dose-dependent inhibition of tumor growth with LXSN/p53 transfection. Tumor growth was inhibited more by p53 gene transfection relative to mock transfection in the presence of Adriamycin. CONCLUSION These treatment modalities could be beneficial in the treatment of p53 mutant positive thyroid cancers.
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Lee SK, Seo DW, Myung SJ, Park ET, Lim BC, Kim HJ, Yoo KS, Park HJ, Joo YH, Kim MH, Min YI. Percutaneous transhepatic cholangioscopic treatment for hepatolithiasis: an evaluation of long-term results and risk factors for recurrence. Gastrointest Endosc 2001; 53:318-23. [PMID: 11231390 DOI: 10.1016/s0016-5107(01)70405-1] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Percutaneous transhepatic cholangioscopy (PTCS) has a major role in the treatment of hepatolithiasis. The aims of this study were to evaluate immediate and long-term results of PTCS treatment and to elucidate the risk factors for recurrence of stones or cholangitis. METHODS A retrospective study was conducted of patients with hepatolithiasis who underwent PTCS treatment. A total of 92 patients underwent PTCS treatment and 68 were followed for 24 to 60 months (median 42 months). RESULTS Complete clearance of stones was achieved in 74 (80%) patients. The rate of complete clearance was significantly lower in patients with severe intrahepatic strictures compared with that for those with no strictures (14 of 24, 58% vs. 16 of 16, 100%, p < 0.01) and those with mild to moderate strictures (14 of 24, 58% vs. 44 of 52, 85%, p < 0.05). Patients with severe intrahepatic strictures had a higher recurrence rate than those with no or mild strictures (100% vs. 28%, p < 0.01). In addition the recurrence rate in patients with advanced biliary cirrhosis (Child's class B or C) was higher than in those with no or mild (Child's class A) cirrhosis (89% vs. 29%, p < 0.01). In patients with type I and II hepatolithiasis (Tsunoda classification), stones recurred in 2 (12%) patients at 28 and 32 months after successful stone removal, without further recurrence afterwards. The recurrence rate in patients with type III and IV hepatolithiasis increased gradually up to 50% at 60 months of follow-up. CONCLUSIONS Severe intrahepatic stricture was the only factor that affected the immediate success rate of PTCS in the treatment of hepatolithiasis. Several risk factors including severe biliary stricture, advanced biliary cirrhosis and Tsunoda type III and IV affected the long-term results.
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Taheri F, Ochoa JB, Faghiri Z, Culotta K, Park HJ, Lan MS, Zea AH, Ochoa AC. L-Arginine regulates the expression of the T-cell receptor zeta chain (CD3zeta) in Jurkat cells. Clin Cancer Res 2001; 7:958s-965s. [PMID: 11300497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
L-Arginine is a versatile amino acid that plays a central role in the normal function of several organ systems including the immune system. Its availability is tightly controlled and varies significantly in different organs and tissues in the body. L-Arginine plays an important role in supporting T-cell proliferation. Its depletion in certain disease states results in a diminished T-cell response. The main purpose of this study was to determine the effect of the depletion of L-arginine on the expression of the T-cell receptor (TCR) proteins. When the helper T-cell line Jurkat was cultured in arginine-free medium, there was a preferential decrease in the expression of the TCR zeta chain (CD3zeta). The reduced expression of CD3zeta was observed within 24 h of culture in L-arginine-free medium and was completely reversed with the replenishment of L-arginine. Furthermore, the absence of L-arginine blocked the normal re-expression of the TCR that had been internalized after antigen stimulation. There also was a significant decrease in proliferation of Jurkat cells in the absence of L-arginine; however, L-arginine depletion did not prevent the up-regulation of the interleukin 2 receptor chains upon stimulation, nor did it significantly diminish the production of interleukin 2. The changes in the expression of CD3zeta chain were not induced by apoptosis. Thus, the availability of L-arginine in the microenvironment may play a significant role in regulating the expression of the TCR.
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Park HJ, Kwon SH, Lee JH, Lee KH, Miyamoto K, Lee KT. Kalopanaxsaponin A is a basic saponin structure for the anti-tumor activity of hederagenin monodesmosides. PLANTA MEDICA 2001; 67:118-21. [PMID: 11301855 DOI: 10.1055/s-2001-11516] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Hederagenin, delta-hederin [hederagenin alpha-L-arabinoside], kalopanax-saponin A [hederagenin 3-O-alpha-L-rhamnosyl(1-->2)-alpha-L- arabinoside], kalopanaxsaponin I [hederagenin 3-O-beta-D-xylosyl(1-->3)-alpha-L- rhamnosyl(1-->2)-alpha-L-arabinoside], and sapindoside C [hederagenin 3-O-beta-D-glucosyl(1-->4)-beta-D-xylsyl (1-->3)-alpha-L-rhamnosyl(1-->2)-alpha-L-arabinoside] were isolated from stem bark of Kalopanax pictus Nakai (Araliaceae). Among glycosides of hederagenin, disaccharide (kalopanaxsaponin A, commonly also called alpha-hederin), trisaccharide (kalopanaxsaponin I), and tetrasaccharide (sapindoside C) showed significant cytotoxicity on several types of tumor cells, while hederagenin itself exhibited only weak cytotoxicity and its monosaccharide (delta-hederin) was non-cytotoxic. From these results, it suggests that the arabinosyl moiety at C-3 blocks the activity of hederagenin and the position of the second sugar for glycoside linkage is also important for cytotoxicity. In the in vivo experiments, kalopanaxsaponin A (15 mg/kg, i.p.) apparently increased the life span of mice bearing Colon 26 and 3LL Lewis lung carcinoma, as well as cisplatin (3 mg/kg, i.p.). These results indicated that kalopanaxsaponin A has potential anti-tumor applications.
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Lee CE, Park HJ. Interleukin-4 induces two distinct GAS-binding complexes containing STAT6: evidence for DNA binding of STAT6 monomer. Mol Cells 2001; 11:28-34. [PMID: 11266117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Treatment of tonsillar mononuclear cells with interleukin-4 (IL-4) rapidly induced the formation of two distinct complexes upon reaction of the cell extracts with the IL-4-responsive element (IL-4RE) of the CD23b promoter in the electrophoretic mobility sift assays (EMSA). The two complexes were detected with a similar activation kinetics upon IL-4 stimulation. They were both immunoreactive with antibodies to signal transducer and activator of transcription (STAT) 6. The upper complex, however, appeared more stable in the competitor oligomer binding assays and more resistant in the anti-phosphotyrosine antibody inhibition assays than the lower complex. Western blot analysis revealed a single peptide of 105 kDa reacting with anti-STAT6 antibodies, which ruled out the possibility for multiple isoforms of STAT6 in these cells. Subsequently, Southwestern analysis demonstrated that monomeric STAT6 in the IL-4-treated nuclear extract can bind the labeled IL-4RE in an activation-dependent manner. Our data strongly suggests that in addition to dimeric STAT6, monomeric STAT6, albeit with a lower affinity, can bind the IL-4RE/gamma activation site (GAS) upon IL-4-induced activation. Also, the upper and lower bands observed in EMSA are likely to represent dimeric and monomeric STAT6 bound to the IL-4RE oligomer, respectively. The functional implication of the STAT6 monomer binding to GAS in the IL-4-induced gene activation is discussed.
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Lee JH, Park HJ, Kim YC, Cinn YW. Two cases of Kimura's disease with unusual clinical manifestations. Dermatology 2001; 201:162-4. [PMID: 11053923 DOI: 10.1159/000018463] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We report 2 cases of Kimura's disease with unusual clinical presentation. Lesions were itching nodules located at the elbow and the dorsum of the hand, and were associated with unusual laboratory values. These features may lead to problems in clinical differential diagnosis.
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Sung J, Han KH, Zo JH, Park HJ, Kim CH, Oh BH. Effects of red ginseng upon vascular endothelial function in patients with essential hypertension. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2001; 28:205-16. [PMID: 10999439 DOI: 10.1142/s0192415x00000258] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study is to estimate the effect of Korean red ginseng on vascular endothelial cell dysfunction in patients with hypertension. Seventeen patients with hypertension who were divided into ginseng-treated (7) and non-treated (10) groups and 10 normotensive subjects were included. To assess the function of the vascular endothelial cell, changes of forearm blood flow to infusion of acetylcholine, sodium nitroprusside and bradykinin in incremental doses were measured by venous occlusion plethysmography. In the ginseng-treated hypertensive group, forearm blood flows at the highest dose of acetylcholine and bradykinin were significantly higher than those of the non-treated hypertensive group and were not different from those of the control group. In the case of sodium nitroprusside infusion, no significant differences were observed between the control, non-treated and treated groups. In conclusion, Korean red ginseng can improve the vascular endothelial dysfunction in patients with hypertension possibly through increasing synthesis of nitric oxide.
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Choi SW, Chung JP, Song YK, Park YN, Chu JK, Kim DJ, Jung JH, Lee CH, Lee SJ, Park HJ, Lee KS, Lee SI, Park IS, Sohn SK. Lower gastrointestinal bleeding due to cytomegalovirus ileal ulcers in an immunocompetent man. Yonsei Med J 2001; 42:147-51. [PMID: 11293496 DOI: 10.3349/ymj.2001.42.1.147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Cytomegalovirus (CMV) infections are commonly reported in severely immunocompromised hosts and ulcers of the alimentary tract are frequently observed in systemic CMV infections. However, invasive and ulcerative disease of the gastrointestinal (GI) tract caused by CMV has also been reported in healthy adults. Many reports show that a CMV infection can produce localized ulcerations in the esophagus, stomach, small intestine, and colon in nonimmunocompromised individuals. The most common site of involvement by CMV infection in the GI tract is the colon followed by the upper GI tract and the least common site is the small intestine. Although GI bleeding is one of the major presenting symptoms of patients with CMV infections of the GI tract, lower GI bleeding due to CMV ileal ulcers in immunocompetent patients, to our knowledge, has not been reported in the English literature. Recently, we experienced a case of lower GI bleeding due to CMV ileal ulcers in a 57-year-old man who had no evidence of immunocompromise. This case suggests that small intestinal ulcers due to CMV infection should be included in the differential diagnosis of lower GI bleeding even in immunocompetent hosts.
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Park HJ, Uhm KB, Hong C. Reduction in intraocular pressure after laser in situ keratomileusis. J Cataract Refract Surg 2001; 27:303-9. [PMID: 11226799 DOI: 10.1016/s0886-3350(00)00782-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE To investigate whether intraocular pressure (IOP) measured on the nasal side is affected after laser in situ keratomileusis (LASIK). SETTING The Glaucoma Service, Dr. Hong's Eye Clinic, Seoul, Korea. METHODS In 83 patients, IOP was prospectively measured with the Goldmann tonometer at the central (Tcenter) and nasal (Tnasal) areas of the cornea before and after LASIK. The Tcenter and Tnasal IOP between baseline and 1, 3, and 6 months postoperatively was compared. The correlation between ablation depth, amount of treatment, refractive change, and change in central corneal thickness and Tcenter change was evaluated. RESULTS Six months after LASIK, Tcenter IOP decreased 3.9 mm Hg (25.2%) and Tnasal IOP decreased 2.0 mm Hg (12.7%) (P < .001, P = .02, respectively). The Tnasal measurement was 1.8 mm Hg higher than the Tcenter measurement (P < .001). Significant correlation between each corneal parameter and the Tcenter reduction at 1 month did not continue to 6 months (P > .05). CONCLUSION At each follow-up, Tnasal IOP was statistically lower than at baseline, although the reduction was not as great as that of Tcenter IOP. A 2 to 3 mm Hg drop in Tnasal up to 6 months after LASIK should be expected. An alternative would be to measure IOP with the Tono-Pen on the nasal side to fit the tip to the relatively unchanged nasal side of the cornea.
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Oh CW, Park BC, Ihn JC, Park HJ. Primary unreamed intramedullary nailing for open fractures of the tibia. INTERNATIONAL ORTHOPAEDICS 2001; 24:338-41. [PMID: 11294426 PMCID: PMC3619918 DOI: 10.1007/s002640000174] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Forty-six open tibial fractures (42 patients) were treated by primary unreamed intramedullary nailing, with debridement of open wounds and treatment of soft tissue. According to Gustilo-Anderson classification there were 18 grade I cases, 18 grade II cases and 10 grade III cases. The incidence of infection was low with two cases of superficial infection and one of deep infection. The mean time for union was 21.9 weeks and the rate of nonunion was 10.8%. There was no significant difference in the mean time to union, infection rate and rate of nonunion with different site and grade of fracture, but there was a longer union time and a higher rate of nonunion in complex and comminuted fractures. Unreamed intramedullary nailing, with appropriate soft tissue treatment, gives good results in the treatment of open tibial fractures including grade III.
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Lee KS, Lee SJ, Park HJ, Chung JP, Han KH, Chon CY, Lee SI, Moon YM. Oxidative stress effect on the activation of hepatic stellate cells. Yonsei Med J 2001; 42:1-8. [PMID: 11293487 DOI: 10.3349/ymj.2001.42.1.1] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Collagen is the most excessive extracellular matrix protein in hepatic fibrosis. Activated, but not quiescent, hepatic stellate cells (HSCs) have a high level of collagen and a smooth muscle actin (alpha SMA) expression. HSCs play a key role in the pathogenesis of hepatic fibrosis. We analyzed a mechanism leading to HSC activation by evaluating the role of oxidative stress and the expression of NFkB. In vitro study HSCs were proliferated (PCNA:2% vs 68%) and activated (alpha SMA: 5% vs 78%) by ascorbate/FeSO4, and HSCs activated by type I collagen were blocked (PCNA: 97% vs 4%, a SMA: 86% vs 9%) by a-tocopherol. In vivo study means of a SMA positive cells in liver at 400 x HPF were 48.3+/-5.2 and 15.2+/-1.8 and [3H]thymidine uptake of HSC was 529.2+/-284.8 cpm and 223.0+/-86.3 cpm in control and a-tocopherol treated group respectively at 32 hours after CCl4 injection. Nuclear extracts from activated, but not from quiescent, HSCs formed a complex with the NFkB cognate oligonucleotidesand alpha-tocopherol inhibited this bindings. This study indicates that oxidative stress plays an essential role through the induction of NFkB on HSC activation.
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Lee KT, Choi JH, Kim DH, Son KH, Kim WB, Kwon SH, Park HJ. Constituents and the antitumor principle of Allium victorialis var. platyphyllum. Arch Pharm Res 2001; 24:44-50. [PMID: 11235811 DOI: 10.1007/bf02976492] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
To search for cytotoxic components from Allium victorialis, MTT assays on each extract and an isolated component, gitogenin 3-O-lycotetroside, were performed against cancer cell lines. Cytotoxicities of most extract were shown to be comparatively weak, though IC50 values of CHCl3 fraction was found to be <31.3-368.4 microg/ml. From the incubated methanol extract at 36 degrees C, eleven kinds of organosulfuric flavours were predictable by GC-MS performance. The most abundant peak was revealed to be 2-vinyl-4H-1,3-dithiin (1) by its mass spectrum. Further, this extract showed significant cytotoxicities toward cancer cell lies. Silica gel column chromatography of the n-butanol fraction led to the isolation of gitogenin 3-O-lycotetroside (3) along with astragalin (4) and kaempferol 3, 4'-di-O-beta-D-glucoside (5). This steroidal saponin exhibited significant cytotoxic activities (IC50, 6.51-36.5 microg/ml) over several cancer cell lines. When compound 3 was incubated for 24 h with human intestinal bacteria, a major metabolite was produced and then isolated by silica gel column chromatography. By examining parent- and prominent ion peak in FAB-MS spectrum of the metabolite, the structure was speculated not to be any of prosapogenins of 3, suggesting that spiroketal ring were labile to the bacterial reaction. These suggest that disulfides produced secondarily are the antitumor principles.
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