401
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Park SH, Kim YK, Park JW, Lee B, Lee BJ. Solution structure of the antimicrobial peptide gaegurin 4 by H and 15N nuclear magnetic resonance spectroscopy. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:2695-704. [PMID: 10785392 DOI: 10.1046/j.1432-1327.2000.01287.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Gaegurin 4 (GGN4) is a 37-residue antimicrobial peptide isolated from the skin of a Korean frog, Rana rugosa. This peptide shows a broad range of activity against prokaryotic cells but shows very little hemolytic activity against human red blood cells. The solution structure of GGN4 was studied by using circular dichroism (CD) and NMR spectroscopy. CD investigations revealed that GGN4 adopts mainly an alpha-helical conformation in trifluoroethanol/water solution, in dodecylphosphocholine and in SDS micelles, but adopts random structure in aqueous solution. By using both homonuclear and heteronuclear NMR experiments, complete 1H and 15N resonance assignments were obtained for GGN4 in 50% trifluoroethanol/water solution. The calculated structures of GGN4 consist of two amphipathic alpha-helices extending from residues 2-10 and from residues 16-32. These two helices are connected by a flexible loop spanning between the residues 11 and 15. By using enzyme digestion and matrix-assisted laser desorption/ionization mass spectroscopy, we confirmed that GGN4 contains a disulfide bridge formed between the residues Cys31 and Cys37 in its C-terminus. The effect of disulfide bridge on the structure and the activity of GGN4 was investigated. The reduced form of GGN4 revealed a similar activity and conformation to native GGN4, suggesting that the disulfide bridge does not strongly affect the conformation and the antimicrobial activity of GGN4.
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402
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Shin JH, Lee HK, Jeon SR, Park SH. Spinal intradural capillary hemangioma: MR findings. AJNR Am J Neuroradiol 2000; 21:954-6. [PMID: 10815676 PMCID: PMC7976756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
We report a case of a spinal intradural capillary hemangioma. On MR images, a well-circumscribed intradural mass was detected at the T8-T9 level. The signal intensity of the mass relative to the spinal cord was isointense on T1-weighted images, hyperintense on T2-weighted images, and showed homogeneous, strong enhancement on contrast-enhanced T1-weighted images. The mass had both extramedullary and intramedullary components.
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403
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Kim H, Suh PG, Ryu SH, Park SH. Assignment of the human PLC delta4 gene (PLCD4) to human chromosome band 2q35 by fluorescence in situ hybridization. CYTOGENETICS AND CELL GENETICS 2000; 87:254-5. [PMID: 10702683 DOI: 10.1159/000015437] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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404
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Kim H, Jung YK, Kwon YK, Park SH. Assignment of apoptotic protease activating factor-1 gene (APAF1) to human chromosome band 12q23 by fluorescence in situ hybridization. CYTOGENETICS AND CELL GENETICS 2000; 87:252-3. [PMID: 10702682 DOI: 10.1159/000015436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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405
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Park SH, Park SY, Kim DW, Chun YH. Chromosomal aberrations in ovarian malignant brenner tumor cell line using chromosome painting. CANCER GENETICS AND CYTOGENETICS 2000; 118:151-3. [PMID: 10748297 DOI: 10.1016/s0165-4608(99)00184-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cytogenetic changes in an ovarian malignant Brenner tumor cell line, SNU-840, were investigated by chromosome painting and G-banding. All chromosome alterations were confirmed by the use of multiple chromosome paintings, which also demonstrated a number of additional alterations.
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406
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Kim H, Suh PG, Ryu SH, Park SH. Assignment of the human PLC delta3 gene (PLCD3) to human chromosome band 17q21 by fluorescence in situ hybridization. CYTOGENETICS AND CELL GENETICS 2000; 87:209-10. [PMID: 10702670 DOI: 10.1159/000015469] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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407
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Park SH, Chin HG, Cho MJ, Martienssen RA, Han CD. Inhibitor of striate conditionally suppresses cell proliferation in variegated maize. Genes Dev 2000; 14:1005-16. [PMID: 10783171 PMCID: PMC316532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Since the work done by R.A. Emerson in the 1930s, Inhibitor of striate (Isr) has been recognized as a dose-dependent genetic modifier of variegation in chlorotic leaf striping mutants of maize such as striate2 (sr2). We have shown that Isr specifically inhibits proliferation and differentiation of plastid defective cells in sr2 mutants. Leaf narrowing is due to loss of intermediate veins and ground tissue located at leaf margins, and the few remaining plastid defective cells are of irregular size and aberrant organization. The Isr gene has been cloned by targeted transposon tagging. Isr mRNA is expressed throughout young leaves, but Isr chimeras indicate that the expression of Isr at leaf margins is sufficient to suppress both the lateral expansion of sr2 leaves and the extent of striping. Isr protein appears to encode a chloroplast protein with sequence similarity to a family of bacterial phosphatases involved in carbon catabolite repression or in carbon metabolism. We propose that the action of Isr in nuclear and plastid communication could be triggered by carbon stress.
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408
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Hong SM, Ha H, Suh JH, Kim KK, Khang SK, Ro JY, Park SH. Clinicopathologic analysis of 124 biopsy-proven peripheral nerve diseases. J Korean Med Sci 2000; 15:211-6. [PMID: 10803700 PMCID: PMC3054620 DOI: 10.3346/jkms.2000.15.2.211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We reviewed dinical, histological and ultrastructural findings of 124 cases of sural nerve biopsy specimens to delineate the trends of peripheral nerve diseases in our institute. Eighty-one were men and 43 were women. We categorized them into five groups: specific diagnosis (66 cases, 53.2%), axonal degeneration type (47 cases, 37.9%), demyelinating type (4 cases, 3.2%), mixed axonal degeneration-demyelinating type (6 cases, 4.8%) and normal (1 case, 0.9%). Cases with specific diagnosis included 21 inflammatory demyelinating polyneuropathy (15 chronic inflammatory demyelinating polyradiculoneuropathy, 6 Guillain-Barre disease), 13 hereditary motor and sensory neuropathy (7 Charcot-Marie-Tooth type I, 6 Charcot-Marie-Tooth type II), 10 vasculitis, 6 toxic neuropathy, 4 leprosy, 3 diabetic neuropathy, 2 alcoholic neuropathy, 1 Fabry's disease and other specific diseases (5 cases). In our cases, the proportion of specific diagnoses was higher, while the proportion of demyelinating peripheral neuropathies and normal were lower than those of Western series. The results of this study indicate that 1) a dose clinicopathologic correlation is important to make a precise diagnosis of peripheral nerve biopsy, 2) Biopsy under strict indication may reduce unnecessary histologic examination, 3) There is no difference in disease pattern of peripheral neuropathy between Western people and Koreans.
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409
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Abstract
This study was performed to evaluate the static and dynamic magnetic resonance imaging (MRI) contrast enhancement pattern of progressive massive fibrosis (PMF) in coal workers' pneumoconiosis. Eighteen lesions in 12 patients were evaluated using a 1.5-T MR unit. T1-weighted FLASH images were obtained before and 0.5, 1, 2, 3, 4, 5, 7.5, 10, 12.5, and 15 minutes after injection of gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA; 0.1 mmol/kg). Imaging findings, the contrast enhancing pattern, enhancement time curve, and the contrast uptake equivalent (CE; mmol/L) were evaluated. On T1-weighted images, 14 lesions showed high signal intensity, and four showed low signal intensity. On T2-weighted images, all lesions were of low signal intensity and were indistinguishable from aerated lung parenchyma. After contrast infusion, all lesions except two enhanced markedly. The time enhancement curve showed a marked, gradual increase in signal intensity up to 3 minutes, a subtle increase in signal intensity up to 7.5 minutes, and then a plateau until 15 minutes after Gd-DTPA injection. Characteristic MR findings of PMF in coal workers' pneumoconiosis include T1 high signal intensity, T2 low signal intensity, and marked postinfusion enhancement. The time enhancement curve shows a marked, gradual increase of signal intensity up to 3 minutes and plateau up to 15 minutes.
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410
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Abstract
Although light microscopic features of muscle are not pathognomonic in most cases of myasthenia gravis (MG), careful examination of neuromuscular junction by electron microscopy (EM) can reveal important clues for this disease. We report here a case of MG confirmed by EM study to emphasize that tissue diagnosis is still the best adjuvant to confirm the diagnosis. An 18-year-old female visited our hospital complaining of progressive muscle weakness for 3 years. She had difficulty in running, going upstairs and doing routine activities. Symptoms were aggravated with continuous work and resolved after rest. She had weakness of bilateral masseter and facial muscles and proximal portions of extremities without definite diurnal variation. Electromyography showed myopathic changes in proximal muscles of extremities. MG was considered but tensilon test was equivocal. Repetitive nerve stimulation tests revealed 20-30 percent decrease in responses to low and high rate stimulation. Muscle biopsy revealed selective type 2 atrophy. Ultrastructurally, abnormalities of neuromuscular junctions, i.e., wide primary synaptic cleft, and wide and shallow secondary synaptic clefts with mild myopathic features were present. These findings were pathognomonic for MG. Later, her symptoms were improved completely 3 months after thymectomy. The histologic finding of thymus was follicular hyperplasia.
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411
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Lim DY, Park GH, Park SH. Inhibitory mechanism of pinacidil on catecholamine secretion from the rat perfused adrenal gland evoked by cholinergic stimulation and membrane depolarization. JOURNAL OF AUTONOMIC PHARMACOLOGY 2000; 20:123-32. [PMID: 11095550 DOI: 10.1046/j.1365-2680.2000.00171.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. The present study attempted to investigate the effect of potassium channel openers on secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from rat isolated perfused adrenal gland. 2. The perfusion of pinacidil (30-300 microM) into an adrenal vein for 20 min produced dose-dependent inhibition of CA secretion evoked by acetylcholine (ACh; 5.32 mM), high K+ (56 mM), 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP; 100 microM for 2 min), 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyl trimethyl ammonium chloride (McN-A-343; 100 microM for 2 min), cyclopiazonic acid (CPA; 10 microM for 4 min) and methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)-pyri dine-5-carboxylate (Bay-K-8644; 10 microM for 4 min). 3. In the presence of minoxidil (100 microM), which is also known to be a potassium channel activator, CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and CPA were also significantly depressed. 4. In adrenal glands preloaded with pinacidil (100 microM) in the presence of glibenclamide (GB; 1 microM), a specific blocker of ATP-regulated potassium channels, CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and CPA were restored to a considerable extent of the control release as compared with that of pinacidil only. 5. These results suggest that pinacidil causes marked inhibition of CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors, as well as by membrane depolarization, indicating that this effect may be mediated by inhibiting influx of extracellular calcium and release of intracellular calcium in the rat adrenomedullary chromaffin cells. Furthermore, these findings suggest that these potassium channel opener-sensitive membrane potassium channels also play a modulatory role in regulating CA secretion.
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412
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Bae JW, Choi KH, Kim HG, Park SH. The detection of circulating breast cancer cells in peripheral blood by reverse transcriptase-polymerase chain reaction. J Korean Med Sci 2000; 15:194-8. [PMID: 10803697 PMCID: PMC3054626 DOI: 10.3346/jkms.2000.15.2.194] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Some circulating cancer cells in the blood play a central role in the metastatic process and may have a major influence on patient progress. Their numbers can be very small and techniques for their detection need to be both sensitive and specific. Polymerase chain reaction (PCR) has been successfully used to detect small numbers of tumor cells in cancer. We used a reverse transcriptase-polymerase chain reaction (RT-PCR) to detect circulating breast cancer cells in venous blood samples before operations and assessed cytokeratin-19 (CK-19) and cytokeratin-20 (CK-20) as target mRNA markers in the blood of healthy donors (n=6) and breast cancer patients (n=30) with American Joint Committee on Cancer stages 0 to IIIa. CK-19 mRNA was expressed in all blood samples of healthy donors and patients. But CK-20 was the only mRNA marker not detected in the blood from healthy donors. Seven of 30 (23%) venous blood isolates of breast cancer patients yielded a CK-20 mRNA with positive results. There was no correlating CK-20 mRNA expression with stage and axillary lymph node status. In conclusion, CK-19 showed no diagnostic value as a mRNA marker in the detection of circulating cancer cells by RT-PCR assay because this was expressed in the blood of healthy donors. CK-20 mRNA was an useful marker to detect circulating cancer cells in breast cancers.
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413
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Han HJ, Lee YH, Park SH. Estradiol-17beta-BSA stimulates Ca(2+) uptake through nongenomic pathways in primary rabbit kidney proximal tubule cells: involvement of cAMP and PKC. J Cell Physiol 2000; 183:37-44. [PMID: 10699964 DOI: 10.1002/(sici)1097-4652(200004)183:1<37::aid-jcp5>3.0.co;2-n] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effect of estradiol-17beta-BSA (E(2)-BSA) on Ca(2+) uptake and its related signal pathways were examined in the primary cultured rabbit kidney proximal tubule cells. E(2)-BSA (10(-9) M) significantly stimulated Ca(2+) uptake from 2 h by 13% and at 8 h by 35% as compared to control, respectively. This stimulatory effect of E(2)-BSA was not inhibited by tamoxifen (10(-8) M, an intracellular estrogen receptor antagonist), actinomycin D (10(-7) M, a transcription inhibitor), and cycloheximide (4 x 10(-5) M, a protein synthesis inhibitor). However, E(2)-BSA-induced stimulation of Ca(2+) uptake was blocked by methoxyverapamil (10(-6) M, an L-type calcium channel blocker) and 5-(N-ethyl-N-isopropyl)-amiloride (10(-5) M, a Na(+)/H(+) antiporter blocker). These results suggest that E(2)-BSA stimulates Ca(2+) uptake through nongenomic pathways. Thus, we investigated which signal pathways were related to E(2)-BSA-induced stimulation of Ca(2+) uptake. 8-Br-cAMP (10(-6) M) alone increased Ca(2+) uptake by 22% compared to control. When E(2)-BSA combined with 8-Br-cAMP, Ca(2+) uptake was not significantly stimulated compared to E(2)-BSA. SQ 22536 (10(-6) M, an adenylate cyclase inhibitor) and myristoylated protein kinase A inhibitor amide 14-22 (10(-6) M, a protein kinase A inhibitor) blocked E(2)-BSA-induced stimulation of Ca(2+) uptake and E(2)-BSA also increased cAMP generation by 26% of that of control. In addition, TPA (0.02 ng/ml, an artificial PKC promoter) stimulated the Ca(2+) uptake by 14%, and the cotreatment of TPA and E(2)-BSA did not significantly stimulate Ca(2+) uptake compared to E(2)-BSA. E(2)-BSA-induced stimulation of Ca(2+) uptake was blocked by U 73122 (10(-6) M, a phospholipase C inhibitor) or bisindolylmaleimide I (10(-6) M, a protein kinase C inhibitor). Indeed, E(2)-BSA stimulated PKC activity by 26%. In conclusion, E(2)-BSA (10(-9) M) stimulated Ca(2+) uptake by nongenomic action, which is mediated by cAMP and PKC pathways.
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414
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Hahn MJ, Yoon SS, Sohn HW, Song HG, Park SH, Kim TJ. Differential activation of MAP kinase family members triggered by CD99 engagement. FEBS Lett 2000; 470:350-4. [PMID: 10745095 DOI: 10.1016/s0014-5793(00)01330-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The molecular basis for the modulatory properties of CD99 is not well understood. Treatment of human Jurkat T lymphocytes with anti-CD99 antibody led to activation of three mitogen-activated protein kinase (MAPK) members, ERK, JNK, and p38 MAPK, along with homotypic aggregation. While phosphorylation of ERK and JNK was inhibited by the pretreatment of a PKC inhibitor, bisindolylmaleimide I, activation of p38 MAPK was upregulated by the same pretreatment. The signaling pathways to MAPKs by CD99 engagement were independent of PI-3 kinase, distinguishing from those by CD3 engagement. Among MAPKs, ERK pathway was essential for homotypic aggregation together with intracytoplasmic Ca(2+).
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415
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Park SH, Benlagha K, Lee D, Balish E, Bendelac A. Unaltered phenotype, tissue distribution and function of Valpha14(+) NKT cells in germ-free mice. Eur J Immunol 2000. [PMID: 10671219 DOI: 10.1002/1521-4141(200002)30:2<620::aid-immu620>3.0.co;2-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The expression pattern of mouse CD1d and the tissue distribution of CD1d-restricted Valpha14-Jalpha281 NKT cells suggest that the liver and the marginal zone of the spleen might be preferred sites of activation of this potent innate pathway of early cytokine secretion. Because these tissues are particularly involved with the filtration of blood-borne pathogens, and because NKT cells with an activated / memory phenotype accumulate over the first weeks of life and their CD1 ligands bind microbial glycolipids, it has been hypothesized that expansion of the NKT cell subset may be driven by exposure to the microbial environment. To test this hypothesis, we analyzed the frequency, surface phenotype and functional properties of NKT cells in normal and in germ-free C57BL / 6 mice. Surprisingly, we found that the NKT cell subset develops in the presence or absence of a microbial environment. Although these results do not rule out the possibility that NKT cells exert a protective function against some microbial agents, they demonstrate that non microbial ligands, possibly self-antigens are sufficient for the generation, maturation and peripheral accumulation of NKT cells.
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416
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Ahn DS, Yoon ES, Koo SH, Park SH. A prospective study of the anatomic variations of the median nerve in the carpal tunnel in Asians. Ann Plast Surg 2000; 44:282-7. [PMID: 10735220 DOI: 10.1097/00000637-200044030-00006] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A prospective study of anatomic variations of the median nerve and its relationship to the surrounding structures was performed of 354 consecutive operations in 192 patients with carpal tunnel syndrome at Korea University Anam Hospital from July 1995 to September 1997. A total of 184 patients were women and 8 patients were men. A total of 162 patients were bilateral and 30 were unilateral. Regarding the course of the motor branch, the extraligamentous type was most common (96.1%, 340 patients). A total of 81.1% of patients (N = 287) had the origin of the motor branch at the radial side of the median nerve (or radial one third), and 17.2% of patients (N = 61) had the origin of the motor branch at the anterior portion of the median nerve. Of these 61 patients, 30 patients (49.1%) were of the preligamentous type. Only one motor nerve branch was found in 89.5% of patients (N = 317), and multiple branches were found in 10.5% of patients. As a result of the comparison between two hands when both hands were operated, the origin and number of motor branches and their courses were identical in most patients (>60%). Hypertrophy of the flexor pollicis brevis was found in 8.5% of patients (N = 30), hypertrophy of the palmaris brevis was found in 4.2% of patients (N = 15), absence of the palmaris longus was discovered in 0.6% of patients (N = 2), existence of the median artery was found in 0.6% of patients (N = 2), and high division of the median nerve rejoining with the thenar motor nerve was found in 0.3% of patients (N = 1). Clearly, the anatomy of the carpal tunnel in Koreans is somewhat different, in part, from the results obtained from studies of whites, but overall results are not significantly different. These results can help obtain a better surgical outcome and complete decompression of the median nerve during operation while preventing inappropriate or inadvertent injury to the motor branch of the median nerve in Koreans.
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417
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Park SH, Lee SJ, Chung HY, Kim TH, Cho CK, Yoo SY, Lee YS. Inducible heat-shock protein 70 is involved in the radioadaptive response. Radiat Res 2000; 153:318-26. [PMID: 10669554 DOI: 10.1667/0033-7587(2000)153[0318:ihspii]2.0.co;2] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Park, S-H., Lee, S-J., Chung, H-Y., Kim, T-H., Cho, C-K., Yoo, S-Y. and Lee, Y-S. Inducible Heat-Shock Protein 70 Is Involved in the Radioadaptive Response. The thermoresistant (TR) clone of radiation-induced fibrosarcoma (RIF) cells showed an adaptive response, i.e. a reduced effect, after exposure to a higher challenging dose (4 Gy) when the priming dose (1 cGy) was given 4 or 7 h earlier, but RIF cells did not. Since inducible Hsp70 expression was different in cells of these two cell lines, the role of inducible Hsp70 in the adaptive response was examined. When inducible Hsp70 was transfected into RIF cells, the adaptive response was acquired. Transfection of inducible Hsp70 to NIH 3T3 mouse embryo cells also conferred radioresistance to the cells as assayed by clonogenic survival, [(3)H]thymidine incorporation, and an ELISA cell death detection kit. An increased tendency for the induction of an adaptive response was also observed. Interestingly, basal levels of Ca(2+)-dependent and independent Pkc activities were increased by transfection with inducible Hsp70 compared to those of control vector cells. Irradiation with gamma rays induced activation of Pkc within minutes in control vector cells, while transfection with inducible Hsp70 did not. Cellular redistribution to particulate fractions of Pkca, d and z after exposure gamma rays also was not detected. Furthermore, radioresistance by transfection with inducible Hsp70, as tested by clonogenic survival, disappeared after pretreatment with Pkc inhibitors, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H7), prolonged treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA), and GF109203X. Taken together, these data suggest that radioresistance inducible by Hsp70 is associated with an elevated level of Pkc activity.
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418
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Park SH, Gray WC, Hernandez I, Jacobs M, Ord RA, Sutharalingam M, Smith RG, Van Echo DA, Wu S, Conley BA. Phase I trial of all-trans retinoic acid in patients with treated head and neck squamous carcinoma. Clin Cancer Res 2000; 6:847-54. [PMID: 10741706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Although retinoids show promise for prevention of second primary upper aerodigestive tract tumors, the optimum retinoid, dose, and schedule are unknown. All-trans retinoic acid (ATRA) has greater affinity for retinoic acid receptors and may be more active than other retinoids but has a shorter plasma half life and may up-regulate its own metabolism. We defined the maximum long-term tolerable dose, dosing frequency, pharmacokinetics, and toxicity of ATRA in patients with treated squamous cell carcinoma of the head and neck (SCCHN). Twenty-one patients were randomized to 45, 90, or 150 mg/m2 ATRA either once daily, or as divided doses every 8 h, for 1 year. Pharmacokinetics were assessed periodically. Fourteen men and seven women with previous SCCHN of initial stage I-IV were treated. Grade > or =3 toxicities (reversible) included headache and hypertriglyceridemia in 5 and 6 patients each, mucositis in 2 patients, and hyperbilirubinemia, elevated alkaline phosphatase, colitis, lipasemia, xerostomia, eczema, and arthritis in 1 patient each. The 150-mg/m2 dose was not tolerable. Doses were reduced for grade > or =3 toxicity in seven of eight patients at 90 mg/m2 daily. Three of nine patients at 45 mg/m2/day required dose reduction, two at the once-daily dose. Day 1 ATRA area under the plasma concentration versus time curve (AUC) increased with dose, and after 1-2 months of continued dosing, the AUC declined in 7 of 13 patients (54%) studied. ATRA AUC did not correlate with toxicity severity or frequency. Fifteen mg/m2/day every 8 h is a tolerable dose for 1 year in patients with treated SCCHN. ATRA pharmacokinetics did not correlate with toxicity.
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419
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Kim WU, Yoo WH, Park W, Kang YM, Kim SI, Park JH, Lee SS, Joo YS, Min JK, Hong YS, Lee SH, Park SH, Cho CS, Kim HY. IgG antibodies to type II collagen reflect inflammatory activity in patients with rheumatoid arthritis. J Rheumatol 2000; 27:575-81. [PMID: 10743792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
OBJECTIVE To determine the clinical significance of IgG antibodies to type II collagen (CII) and to define any correlation of antibodies to CII with the inflammatory response in patients with rheumatoid arthritis (RA). METHODS IgG antibodies to native human type II collagen (IgG anti-CII) were measured in sera and synovial fluid (SF) from patients with RA, patients with osteoarthritis (OA), and healthy controls by an improved ELISA. Demographic, clinical, and laboratory data including tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6) levels were also obtained at the time of sampling in patients with RA. RESULTS The median level and positivity for circulating IgG anti-CII were higher in patients with RA (n = 297) than patients with OA (n = 34) and healthy controls (n = 50) (p < 0.001). The titers of IgG anti-CII in SF were also higher in RA (n = 45) than in OA (n = 16) (p < 0.001). In paired samples, the levels of IgG anti-CII were significantly higher in SF compared to the sera in patients with RA (n = 45) (p < 0.001), but levels were not different in patients with OA (n = 16). Circulating IgG anti-CII converted from positive to negative in 13 patients (10.7%) and from negative to positive in 18 patients (14.8%) among 122 patients with RA in whom IgG anti-CII were monitored sequentially at a mean interval of 12.2 months. IgG anti-CII positive patients (n = 98) had shorter disease duration (p = 0.04) and less frequent deformity (p = 0.013), and higher median erythrocyte sedimentation rate (ESR) (p = 0.001) and C-reactive protein (CRP) (p < 0.001) than IgG anti-CII negative patients (n = 120). The levels of IgG anti-CII correlated with CRP (r = 0.270) and ESR (r = 0.253). CRP decreased significantly in patients (n = 13) who converted from IgG anti-CII positive to negative (p = 0.013). IgG anti-CII positive patients (n = 40) had higher levels of TNF-alpha and IL-6 than negative patients (n = 40) (p < 0.001). Levels of IgG anti-CII correlated well with TNF-alpha (r = 0.617) and IL-6 (r = 0.347). CONCLUSION Increased IgG anti-CII in sera and SF in RA correlated directly with acute phase reactants and the proinflammatory cytokines TNF-alpha and IL-6. Our data suggest that IgG anti-CII could reflect inflammatory activity with a potential to destroy cartilage in the early stages of RA.
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420
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Han HJ, Choi HJ, Park SH. High glucose inhibits glucose uptake in renal proximal tubule cells by oxidative stress and protein kinase C. Kidney Int 2000; 57:918-26. [PMID: 10720945 DOI: 10.1038/sj.ki.4491414] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND High glucose has been considered to play an important role in alteration of renal proximal tubule transporter's activity. This study examined the mechanism by which high glucose modulates alpha-methyl-D-glucopyranoside (alpha-MG) uptake in primary cultured rabbit renal proximal tubule cells (PTCs). METHODS PTCs were incubated with 25 mmol/L glucose alone or combined with taurine, ascorbic acid, catalase, staurosporine, and bisindolylmaleimide I. Then alpha-MG uptake and lipid peroxide (LPO) formation were examined. RESULTS Twenty-five mmol/L glucose from four hours, but not 25 mmol/L mannitol, inhibited alpha-MG uptake by 23% compared with 5 mmol/L glucose (control). In the study to examine the relationship of oxidative stress in the high-glucose-induced inhibition of alpha-MG uptake, 25 mmol/L glucose significantly increased LPO by 27% compared with control. However, 10 mmol/L glucose did not affect alpha-MG uptake and LPO formation. Taurine (2 mmol/L), ascorbic acid (1 mmol/L), endogenous antioxidants, or catalase (600 U/mL) significantly blocked 25 mmol/L glucose-induced increase of LPO formation and inhibition of alpha-MG uptake. In the experiment to examine the effects of protein kinase C on LPO formation, 12-O-tetradecanoylphorbol-13-acetate (TPA; 100 ng/mL) increased LPO formation, and staurosporine (10(-7) mol/L) and bisindolylmaleimide I (10(-6) mol/L) totally blocked 25 mmol/L glucose-induced increase of LPO formation and inhibition of alpha-MG uptake. In addition, taurine reduced TPA-induced increase of LPO formation and inhibition of alpha-MG uptake. CONCLUSION High glucose induces, in part, the inhibition of alpha-MG uptake through LPO formation, and activation of protein kinase C may play a role in high-glucose-induced LPO formation in the primary cultured rabbit renal PTCs.
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421
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Park SH, Han JK, Choi BI, Kim M, Kim YI, Yeon KM, Han MC. Heterotopic pancreas of the stomach: CT findings correlated with pathologic findings in six patients. ABDOMINAL IMAGING 2000; 25:119-23. [PMID: 10675449 DOI: 10.1007/s002619910028] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND The purpose of this study was to characterize the computed tomographic (CT) findings of heterotopic pancreas of the stomach. METHODS CT scans of six surgically proven cases of heterotopic pancreas of the stomach were reviewed. Three were dynamic spiral CT scans, with both arterial dominant and late phase scans. In other three, both unenhanced and contrast-enhanced scans were obtained by using conventional techniques. Particular attention was given to the enhancement of the heterotopic pancreas. Pathologic and surgical findings were correlated with CT findings. RESULTS The locations were in the gastric antrum in five cases and in the mid-body in one. Size ranged from 1 cm to 3 cm (mean = 2.1 cm). Three cases showed homogeneous, strong enhancement similar to the pancreas and consisted mainly of pancreatic acini with the same histologic features as the normal pancreas. Two cases showed poor enhancement and consisted mainly of ducts and hypertrophied muscle; pancreatic acini were a minor component. In one case appearing as a cystic lesion on CT, a pseudocyst was found with many ducts and some nests of pancreatic acini. CONCLUSIONS Heterotopic pancreas of the stomach showed a diverse spectrum of CT findings. Good understanding of these CT findings may be helpful in making a correct diagnosis.
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422
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Kasuya J, Liang SJ, Goko H, Park SH, Kato K, Xu ZD, Hockman S, Manganiello VC, Fujita-Yamaguchi Y. Cardiac type cGMP-inhibited phosphodiesterase (PDE3A) gene structure: similarity and difference to adipocyte type PDE3B gene. Biochem Biophys Res Commun 2000; 268:827-34. [PMID: 10679291 DOI: 10.1006/bbrc.2000.2226] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phosphodiesterase type 3 isoforms, PDE3A and 3B, are expressed primarily in cardiovascular and adipose tissues, respectively. We previously reported a shorter transcript of 4.4-kb PDE3A which is predominantly transcribed in human placenta, whereas a full-length 7. 6-kb transcript corresponding to the cardiac PDE3A cDNA has not been characterized. Due to unfortunate circumstances created by changes in PDE3 nomenclature, PDE3B gene structure previously reported used PDE3A in its title. Here, we describe PDE3A gene structure, which comprises 16 exons spanning over 130 kb on chromosome 12p12. Two PDE3 isoforms share similar gene organization, but localize to different chromosomes. The most distal transcription initiation site of the PDE3A gene is approximately 1071 bases upstream of the ATG site, suggesting that exon 1 consists of 1071 and 960 bp of untranslated and translated sequences, respectively. The proximal 5'-flanking region, which does not contain TATA-like sequences, exhibited weak but significant promoter activity. Results suggest potential involvement of distal promoter/enhancer and translational regulation for expression of the 7.6-kb transcript.
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423
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Park SM, Han SB, Hong DH, Lee CW, Park SH, Jeon YJ, Kim HM. Effect of extracellular cations on the chemotherapeutic efficacy of anticancer drugs. Arch Pharm Res 2000; 23:59-65. [PMID: 10728659 DOI: 10.1007/bf02976468] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Cancer development and the efficiency of chemotherapy relies on the patients calcium-related pathological status such as hyper- or hypocalcemia. In the present study, we investigated the effect of extracellular cations such as calcium and magnesium on the therapeutic efficacy of antitumor drugs. The analytic parameters used were cellular drug uptake/excretion and the chemosensitivity of the human breast cancer cell lines, MCF7 and MCF7/ADR. Both calcium and magnesium ions decreased the membrane permeability of cancer cells, which was determined by cell size analysis. These divalent ions also lowered the drug uptake and the cytoplasmic levels of rhodamine 123 and adriamycin, suggesting that they might interfere with the diffusion of these drugs by modifying the physical properties of the cytoplasmic membrane. The acute cytotoxicity of adriamycin after a short period of incubation correlated with changes in its cytoplasmic level. Our results indicate that these extracellular cations might play an important role in the therapeutic activities of anticancer drugs in cancer patients. These results also provide insight a new aspect of chemotherapy, because they suggest that the therapeutic doses of anti-cancer drugs should be modified in cancer-bearing patients presenting with abnormal blood calcium levels.
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424
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Park SH, Benlagha K, Lee D, Balish E, Bendelac A. Unaltered phenotype, tissue distribution and function of Valpha14(+) NKT cells in germ-free mice. Eur J Immunol 2000; 30:620-5. [PMID: 10671219 DOI: 10.1002/1521-4141(200002)30:2<620::aid-immu620>3.0.co;2-4] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The expression pattern of mouse CD1d and the tissue distribution of CD1d-restricted Valpha14-Jalpha281 NKT cells suggest that the liver and the marginal zone of the spleen might be preferred sites of activation of this potent innate pathway of early cytokine secretion. Because these tissues are particularly involved with the filtration of blood-borne pathogens, and because NKT cells with an activated / memory phenotype accumulate over the first weeks of life and their CD1 ligands bind microbial glycolipids, it has been hypothesized that expansion of the NKT cell subset may be driven by exposure to the microbial environment. To test this hypothesis, we analyzed the frequency, surface phenotype and functional properties of NKT cells in normal and in germ-free C57BL / 6 mice. Surprisingly, we found that the NKT cell subset develops in the presence or absence of a microbial environment. Although these results do not rule out the possibility that NKT cells exert a protective function against some microbial agents, they demonstrate that non microbial ligands, possibly self-antigens are sufficient for the generation, maturation and peripheral accumulation of NKT cells.
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Kim Y, Jang DS, Park SH, Yun J, Min BK, Min KR, Lee HK. Flavonol glycoside gallate and ferulate esters from Persicaria lapathifolia as inhibitors of superoxide production in human monocytes stimulated by unopsonized zymosan. PLANTA MEDICA 2000; 66:72-74. [PMID: 10705740 DOI: 10.1055/s-0029-1243112] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Aerial parts of Persicaria lapathifolia S.F. Gray (Polygonaceae) exhibited an inhibitory effect on superoxide production in unopsonized zymosan-stimulated human monocytes. Two known compounds, quercetin 3-O-beta-(2"-galloyl)-glucopyranoside and quercetin 3-O-beta-(2"-galloyl)-rhamnopyranoside, and a new compound, quercetin 3-O-beta-(6"-feruloyl)-galactopyranoside, were isolated as the inhibitors of superoxide production by activity-guided fractionation. IC50 values were shown at the concentrations of 2.1 microM by quercetin 3-O-beta-(2"-galloyl)-glucopyranoside, 1.9 microM by quercetin 3-O-beta-(2"-galloyl)-rhamnoypranoside, and 3.5 microM by quercetin 3-O-beta-(6"-feruloyl)-galactopyranoside whose inhibitory potencies were similar to oxyphenylbutazone (IC50 = 1.9 microM) as a positive control.
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