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Park Y, Lee H, Koh CS, Min H, Zimmet PZ, Rowley MJ, Mackay IR, Trucco M, Dorman JS. Low prevalence of immunogenetic markers of IDDM in adult Koreans with diabetes detected on OGTT. Diabetes Res Clin Pract 1996; 34 Suppl:S37-43. [PMID: 9015668 DOI: 10.1016/s0168-8227(96)90006-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In the Asian populations, it is not uncommon for adult patients with NIDDM to eventually lose beta-cell function and develop IDDM. Accepting that IDDM is an autoimmune disease, which occurs on a genetic background, it could by hypothesized that by measuring autoantibody prevalence and HLA DQ gene polymorphism, known important prediagnostic markers of IDDM, the prevalence of adult-onset IDDM in patients with previously undiagnosed NIDDM patients could be estimated. To do this, anti-GAD prevalence and HLA DQ A1 and DQ B1 polymorphisms after PCR amplification of genomic DNA were analyzed in 121 newly diagnosed diabetic patients of Yonchon cohort and compared to the results with those of 100 matched health control subjects. We also compared the results with those of other populations to assess the difference of genotype distribution. The overall prevalence of anti-GAD antibodies was 1.7% (2 of 121) in patients with previously undiagnosed NIDDM, whereas 1 of 100 controls had positive antibodies. Among those who were positive, their titer of antibodies to GAD were not high. No statistically significant differences in the distribution of either mean levels of anti-GAD or DQA1 and DQB1 alleles were found comparing NIDDM patients to controls. Interestingly, the frequency of DQB1*non-Asp-57 and DQA1*Arg-52 alleles in the Korean adult control population was similar to that of US Caucasians (DQB1*non-Asp-57: 0.431 vs. 0.475; DQA1*Arg-52: 0.492 vs. 0.463). The low prevalence of anti-GAD antibodies and HLA-DQA1 and DQB1 susceptibility alleles among recent-onset NIDDM patients, not different compared to controls suggests that diabetes in Korean adults is unlikely to have an autoimmune component to its pathogenesis.
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602
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Park Y, Lee H, Koh CS, Min H. Community-based epidemiologic study on atherosclerotic cardiovascular risk factors. Diabetes Res Clin Pract 1996; 34 Suppl:S65-72. [PMID: 9015672 DOI: 10.1016/s0168-8227(96)90010-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The present study was undertaken to determine the prevalence of hyperlipidemia and to find out the possible impact of serum lipid profiles on other cardiovascular risk factors in Yonchon County, Korea. Population-based cross-sectional study by random cluster sampling of registered residents over 30 years of age was performed. Out of the 3804 subjects scheduled for the survey, 2520 underwent the actual examination. The prevalence of hypercholesterolemia (serum cholesterol > or = 240 mg/dl) was only 1.2%, whereas that of hypertriglyceridemia (serum triglyceride > or = 250 mg/dl) was as high as 11.3%. The serum levels of cholesterol, triglyceride and HDL cholesterol correlated with anthropometric indices, body mass indices and waist hip ratios. The prevalences of diabetes and/or hypertension increased as either serum cholesterol or triglyceride level increased. In addition, the prevalence rates of obesity, impaired glucose tolerance, hypertriglyceridemia and hypercholesterolemia in its isolated form (free of the others) were much lower than overall prevalence indicating an existence of major overlap among these cardiovascular atherosclerotic risk factors in the form of multiple combinations. Central obesity was found to be an independent associated factor for the aggregation of the conditions related to the increase in cardiovascular risks. The prevalence of hypercholesterolemia in Yonchon County was substantially lower than that previously suggested, albeit that of hypertriglyceridemia was very high. We could also observe a varying degree of transition in cardiovascular risks related to insulin resistance from the rural to the urban area with rapid emergence of non-communicable diseases as a result of modernization.
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603
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Park Y, Li H, Kemper B. Phenobarbital induction mediated by a distal CYP2B2 sequence in rat liver transiently transfected in situ. J Biol Chem 1996; 271:23725-8. [PMID: 8798596 DOI: 10.1074/jbc.271.39.23725] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The promoter activities of the genes for cytochrome P450 2B1 (CYP2B1) and cytochrome P450 2C1 (CYP2C1) have been assayed by direct injection of promoter-luciferase chimeric genes into rat liver. Activities of minimal promoters for CYP2C1 and CYP2B1 were detectable in untreated animals but were not increased by treatment of the animals with phenobarbital. After insertion to the 5' side of the minimal promoters of one to three copies of the CYP2B2 sequence from -2318 to -2155, a phenobarbital-responsive element in primary hepatocyte cultures (Trottier, E., Belzil, A., Stoltz, C., and Anderson, A. (1995) Gene (Amst.) 158, 263-268), phenobarbital treatment induced the activity of the CYP2C1 promoter by 5-15-fold and the CYP2B1 promoter by 2.5-5-fold. Mutation of a basal transcription element-like motif and a CCAAT/enhancer binding protein element in the CYP2B1 proximal promoter region reduced expression, but 3-4-fold induction by phenobarbital was retained. Mutation of the "Barbie box," a putative phenobarbital-responsive element (He, J.-S., and Fulco, A. J. (1991) J. Biol. Chem. 266, 7864-7869) in the CYP2B1 proximal promoter did not reduce the relative response to phenobarbital. These results demonstrate that direct injection of DNA into rat liver may be used to assay phenobarbital responsiveness of cytochrome P450 genes. In this system, a distal CYP2B2 element mediates a response to phenobarbital, and proximal elements, including the Barbie box, are not required for the induction.
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604
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Marhic ME, Park Y, Yang FS, Kazovsky LG. Broadband fiber-optical parametric amplifiers and wavelength converters with low-ripple Chebyshev gain spectra. OPTICS LETTERS 1996; 21:1354-1356. [PMID: 19876350 DOI: 10.1364/ol.21.001354] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Theory predicts that a two-pump fiber optical parametric amplifier or wavelength converter operated near the fiber zero-dispersion wavelength can exhibit a gain spectrum approximated by a Chebyshev polynomial of order 8. Under realistic conditions of pump spacing and fiber dispersion, very low-gain ripple can be obtained over a large bandwidth. For example, a dispersion-shifted fiber can provide a signal amplifier with a gain of 20 dB with 0.2-dB uniformity over a 45-nm bandwidth. Potential limitations are discussed.
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605
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Park Y, Kwon C. Glass phase of randomly polymerized membranes. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 54:3032-3035. [PMID: 9965429 DOI: 10.1103/physreve.54.3032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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606
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Park Y, Kemper B. The CYP2B1 proximal promoter contains a functional C/EBP regulatory element. DNA Cell Biol 1996; 15:693-701. [PMID: 8769571 DOI: 10.1089/dna.1996.15.693] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Cytochromes P450 2B1 and 2B2 (CYP2B1 and CYP2B2) are well-known phenobarbital-inducible genes in rat liver. Potential transcriptional regulatory elements in the proximal promoter regions of rat CYP2B genes were analyzed by transfection in HepG2 hepatoma cells and by binding of nuclear proteins. Deletion of sequences from -1,400 to -110 had modest effects on promoter activity, but further deletion to -57 decreased the transcriptional activity by more than 90%, suggesting the presence of strong cis-acting elements in this region. Sequences similar to a basal transcription element (BTE) in CYP1A1 and a proposed phenobarbital responsive element (Barbie box) are present from -89 to -67. However, no protection was detected in these regions by DNase I footprinting assay. Instead, a region (FP1) from -64 to -45 was protected by liver nuclear extracts. Mutation of either the BTE or FP1 sequences of CYP2B1, or both, reduced transcriptional activity by 70-80% in HepG2 cells. FP1 was identified as a functional C/EBP site by co-transfection of C/EBP expression vectors and supershift assays with C/EBP antisera. Binding of liver nuclear proteins to sequences within the -110 to +1 region was not detectably altered by pretreatment of rats with phenobarbital.
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607
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Abstract
A case is described in which, after administration of diclofenac for 13 days for arthritis attributed to gout, the patient experienced erythema multiforme followed by muscle weakness, elevation of serum creatine phosphokinase (CPK) level from 101 to 83,770 U/L, 100% muscle isoenzyme, blood urea nitrogen (BUN) level from 15 to 87 mg/dL, creatinine level from 1.0 to 2.1 mg/dL and urine myoglobin level to 1,190 micrograms/dL (N < 1.2). The diagnosis was rhabdomyolysis due to diclofenac, with myoglobinuria resulting in mild renal failure. Treatment consisted of discontinuing diclofenac and administering sufficient fluids to prevent progression of myoglobinuric renal failure. Serum CPK level gradually returned to normal by day 50, BUN and creatinine levels by day 28, and muscle strength between day 90 and 180. Rhabdomyolysis due to diclofenac or to other nonsteroidal antiinflammatory drugs has not been reported.
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608
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Eym Y, Park Y, Park C. Genetically probing the regions of ribose-binding protein involved in permease interaction. Mol Microbiol 1996; 21:695-702. [PMID: 8878033 DOI: 10.1046/j.1365-2958.1996.261389.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The ribose-binding protein (RBP) of Escherichia coli, located in the periplasm, binds to ribose and mediates transport and chemotaxis. The regions on the tertiary structure of RBP that interact with the membrane permease, an ABC transporter, were genetically probed by screening a mutation using the chimeric receptor Trz. Trz is a hybrid protein between the periplasmic domain of chemoreceptor Trg and the cytoplasmic portion of osmosensor EnvZ, which provides a system for monitoring the chemotactic interaction of RBP on MacConkey agar plates when coupled with a reporter lacZ fused to an ompC gene. The expression of ompC can be increased by an interaction of ribose-bound RBP with Trz. A transport defect, either in the binding protein or in the membrane permease, causes a signalling-constitutive Lac+ phenotype of Trz even in the absence of ribose. This appears to be due to the presence of a small amount of ribose, which is normally taken up by the high-affinity transport system. By taking advantage of this, we have designed a system for genetic screening that permits a selection for mutations in the binding protein, causing specific defects in permease interaction but not in tactic interaction. Mutant RBPs that were isolated were unable to perform normal ribose uptake and to utilize ribose as a carbon source, while other functions such as taxis and sugar-binding properties were not substantially affected. The mutational changes were repeatedly found in several residues of RBP, concentrating on three surface regions and comprising two domains of the tertiary structure. We suggest that the two regions, including residues 52 and 166, are specifically involved in the permease interaction while the third region, including residues 72, 134, and others, recognizes both the permease and the chemosensory receptor.
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609
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Kang K, Oh JH, Kwon C, Park Y. Generalization in a two-layer neural network with multiple outputs. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 54:1811-1815. [PMID: 9965261 DOI: 10.1103/physreve.54.1811] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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610
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Voss SH, Park Y, Kwon SO, Whalen R, Boyer TD. Role of interleukin 6 and corticosteroids in the regulation of expression of glutathione S-transferases in primary cultures of rat hepatocytes. Biochem J 1996; 317 ( Pt 2):627-32. [PMID: 8713095 PMCID: PMC1217532 DOI: 10.1042/bj3170627] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The effect of recombinant interleukin 6 (rIL-6) on the transcript levels of rat glutathione S-transferase (GST) genes rGSTA2, rGSTP1, rGSTM1 and rGSTM2 was examined in primary cultures of rat hepatocytes. rIL-6 had little effect on the increase in expression of rGSTP1 that occurs in cultured hepatocytes. Dexamethasone (DEX), in contrast, prevented the expression of rGSTP1 by hepatocytes, and rIL-6 in combination with DEX had no additional effect. Neither rIL-6 nor DEX alone had a significant effect on the transcript levels of rGSTA2, rGSTM1 and rGSTM2 in cultured hepatocytes. However, when both were present (15 ng/ml rIL-6 and 10(-7) M DEX) the transcript levels of rGSTA2, rGSTM1 and rGSTM2 decreased significantly (P < 0.05) after 48 h in culture. If the rIL-6 was removed from the cultures after 24 h, the levels of transcripts recovered and were the same at 48 h as cells cultured without rIL-6 for the entire period. Dose-response relationships of rIL-6 with 10(-7) M DEX were determined for transcripts of each GST isoenzyme and the IC50 values were between 1.5 and 7.5 ng/ml. Declines in transcript levels of rGSTA2 were observed with rIL-6 plus 10(-8) or 10(-7) M DEX but not with rIL-6 plus 10(-9), 10(-6), or 10(-5) M DEX. To determine if the cytokine and glucocorticoid effects were mediated by sequences in the 5'-flanking sequence of rGSTA2, a plasmid construct containing a 1.6 kb fragment of the 5'-flanking sequence of the rGSTA2 gene and the chloramphenicol acetyltransferase (CAT) reporter gene was used to transfect rat hepatocytes in primary culture. The addition of rIL-6 and DEX to the culture medium caused a significant (P < 0.05) decrease in CAT activity after 48 h in culture. If rIL-6 was removed after 24 h in culture, CAT activity after an additional 24 h in culture was greater than the CAT activity in cells cultured for 48 h without rIL-6. Therefore cytokines and glucocorticoids may be important physiological regulators of GST expression.
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611
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Baldus S, Park Y, Kotlarek G, Hell K, Fischer R. Expression of Gal beta 1-4GlcNAc sequences by human gastrointestinal neoplasms and their precursors as detected by Erythrina cristagalli and Erythrina corallodendron lectins. Int J Oncol 1996; 9:43-48. [PMID: 21541479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
Lectins from Erythrina cristagalli (EGA) and Erythrina corallodendron (ECorA) are well-known to detect type 2 chain oligosaccharides (Gal beta 1-4GlcNAc). These carbohydrate moieties are the biosynthetic precursors of various ABH and Lewis blood group antigens and are therefore also related to tumor-associated carbohydrate antigens. For this reason, we investigated the expression of ECA and ECorA binding sites in a series of gastric, colorectal and pancreatic carcinomas as well as corresponding normal tissues. Additionally, a series of hyperplastic and adenomatous colorectal polyps was analyzed. According to our results, both lectins exhibited a strong reactivity with the great majority of gastrointestinal carcinomas. Regarding gastric carcinomas, a stronger reactivity with intestinal-type compared to the diffuse-type species could be observed. Some poorly differentiated tumors were not or only very faintly stained. In the case of colorectal carcinomas, liver metastases which were investigated comparatively, exhibited the same binding pattern as the primary tumors. Colorectal adenomas were stained in about half of the cases without significant relation to the grade of cellular atypia. Positivity observed in normal epithelia (i.e, gastric superficial epithelia, fundus neck cells and deep pyloric mucous glands, pancreatic acini and ductal structures) is in keeping with histogenetic relations between these normal histological structures and corresponding neoplasms. In areas exhibiting intestinal metaplasia, various portions showed cytoplasmic staining of columnar cells and/or of goblet cell vacuoles. On the other hand, columnar and goblet cells in normal colorectal tissue were only weakly stained in a number of specimens. Therefore, it can be concluded that Gal beta 1-4GlcNAc is overexpressed in neoplastic colorectal tissues. Summarized, ECA and ECorA are suitable tools to analyze the expression of Gal beta 1-4GlcNAc, the common precursor substance of various tumor-associated type 2 chain antigens in neoplastic tissues.
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612
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Baldus S, Park Y, Kotlarek G, Hell K, Fischer R. Expression of Gal beta 1-4GlcNAc sequences by human gastrointestinal neoplasms and their precursors as detected by Erythrina cristagalli and Erythrina corallodendron lectins. Int J Oncol 1996. [DOI: 10.3892/ijo.9.1.43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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613
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Park Y, Kim H, Hwang I, Kim JE, Park HY, Jin MS, Oh SK, Kim WT. Substitutional site of Co2+ ions in single-crystalline AgGaS2:Co2+. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:15604-15606. [PMID: 9983392 DOI: 10.1103/physrevb.53.15604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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614
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Kim YS, Jo YY, Chang IM, Toida T, Park Y, Linhardt RJ. A new glycosaminoglycan from the giant African snail Achatina fulica. J Biol Chem 1996; 271:11750-5. [PMID: 8662607 DOI: 10.1074/jbc.271.20.11750] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A new glycosaminoglycan has been isolated from the giant African snail Achatina fulica. This polysaccharide had a molecular weight of 29,000, calculated based on the viscometry, and a uniform repeating disaccharide structure of -->4)-2-acetyl,2-deoxy-alpha-D-glucopyranose (1-->4)-2-sulfo-alpha-L-idopyranosyluronic acid (1-->. This polysaccharide represents a new, previously undescribed glycosaminoglycan. It is related to the heparin and heparan sulfate families of glycosaminoglycans but is distinctly different from all known members of these classes of glycosaminoglycans. The structure of this polysaccharide, with adjacent N-acetylglucosamine and 2-sulfo-iduronic acid residues, also poses interesting questions about how it is made in light of our current understanding of the biosynthesis of heparin and heparan sulfate. This glycosaminoglycan represents 3-5% of the dry weight of this snail's soft body tissues, suggesting important biological roles for the survival of this organism, and may offer new means to control this pest. Snail glycosaminoglycan tightly binds divalent cations, such as copper(II), suggesting a primary role in metal uptake in the snail. Finally, this new polysaccharide might be applied, like the Escherichia coli K5 capsular polysaccharide, to the study of glycosaminoglycan biosynthesis and to the semisynthesis of new glycosaminoglycan analogs having important biological activities.
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615
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Park Y, Okuyama N, Hatano Y, Kato N, Sasamoto S, Shimatani S, Yamazaki S, Yanagida M. Adenomyoepithelioma of the Breast: A Case Reprot and a Review of Literature. Breast Cancer 1996; 3:65-69. [PMID: 11091556 DOI: 10.1007/bf02966965] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A 74-year-old woman complained of a small nodule in the outer lower quadrant of her left breast. On physical examination, a 0.9 x 0.8 cm, round-shaped and firmly elastic nodule was palpated. Excisional biopsy was performed. Histologically, the tumor was separated into, with a bicellular pattern, containing both numerous glandular structures and numerous spindle-shaped cells. Immunohistochemical staining for EMA and cytokeratin showed strongly positive immunoreactivity for epithelial cells. Staining for &aipha;-SMA showed strongly positive immunoreactivity for myoepithelial components. Staining for keratin and S-100 protein showed weakly positive immunoreactivity for myoepithelial cells. Microscopically, the tumor was diagnosed as adenomyoepithelioma of the breast. Immunohistochemical examination is needed to distinguish epithelial cell proliferation from myoepithelial cell proliferation. Immunohistochemical examination using antibodies against EMA, alpha-SMA, Keratin, cytokeratin and S-100 protein, is indispensable.
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616
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Park Y, Lee H, Koh CS, Min H, Rowley M, Mackay IR, Zimmet P, McCarthy B, McCanlies E, Dorman J, Trucco M. The low prevalence of immunogenetic markers in Korean adult-onset IDDM patients. Diabetes Care 1996; 19:241-5. [PMID: 8742569 DOI: 10.2337/diacare.19.3.241] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE IDDM is an autoimmune disease that occurs among genetically susceptible individuals. In Asian populations, it is not uncommon for adult patients with NIDDM to eventually lose beta-cell function and develop IDDM. These individuals may be characterized by autoantibodies to GAD and high-risk HLA-DQ alleles, which are unlikely to be prevalent among patients with true NIDDM or in the general population. The objective of the present study was to evaluate and compare the prevalence of these immunogenetic markers in NIDDM patients and healthy nondiabetic individuals from Korea. RESEARCH DESIGN AND METHODS The prevalences of anti-GAD antibodies and HLA-DQA1 and DQB1 alleles among 121 patients with newly diagnosed NIDDM identified from a population-based study in Yonchon, Korea, and 100 matched healthy control subjects were evaluated and compared. RESULTS The overall prevalence of anti-GAD antibodies was 1.7% (2 of 121) in patients with previously undiagnosed NIDDM, whereas 1 of 100 control subjects had a positive test for antibodies. Among those who tested positive, titers of antibodies to GAD were not high. No statistically significant differences in the distributions of either mean levels of anti-GAD antibodies or DQA1 and DQB1 alleles were found comparing NIDDM patients with control subjects. Interestingly, the frequency of DQB1*non-Asp-57 and DQA1*Arg-52 alleles in the Korean adult control population was similar to that in the U.S. white population (DQB1*non-Asp-57: 0.431 vs. 0.475; DQA1*Arg-52: 0.492 vs. 0.463). CONCLUSIONS The low prevalence of anti-GAD antibodies and HLA-DQA1 and DQB1 susceptibility alleles among recent-onset NIDDM patients, which was similar to observations in control subjects, suggests that diabetes in Korean adults is unlikely to have an autoimmune component to its pathogenesis.
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617
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Bergasa NV, Jones A, Kleiner DE, Rabin L, Park Y, Wells MC, Hoofnagle JH. Pilot study of low dose oral methotrexate treatment for primary biliary cirrhosis. Am J Gastroenterol 1996; 91:295-9. [PMID: 8607496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To assess the efficacy of low doses of oral methotrexate as therapy for primary biliary cirrhosis. METHODS Ten symptomatic patients with this disease were treated with methotrexate at a dose of 15 mg/wk in an open label trial. RESULTS Eight patients completed 1 yr of treatment and six completed 2. Pruritus and fatigue decreased in all patients treated for at least 1 yr. Mean levels of serum alkaline phosphatase, ALT, and IgM were less at 1 and 2 yr than corresponding baseline means. Total serum bilirubin increased in three patients during treatment. Serum aminotransferases and alkaline phosphatase became normal in one patient with stage I disease. Although liver biopsies at 1 and 2 yr revealed a decrease in the intensity of the inflammatory infiltrate, they also showed an increase in fibrosis suggestive of disease progression. Methotrexate was discontinued in five patients: for disease progression in four (one at 4 months, one at 1 yr, and two at 2 yr) and for intractable pruritus in one (at 4 months). All patients experienced transient mucositis and intermittent dyspepsia. CONCLUSIONS These findings suggest that methotrexate treatment in patients with primary biliary cirrhosis is not beneficial in patients with advanced disease; in patients with early disease, methotrexate may be associated with amelioration of symptoms, reduction in serum biochemical indices of liver disease, and reduction in hepatic inflammation. However, prospective, randomized controlled trials will be necessary for definitive evaluation of the effects of methotrexate on the quality of life and survival of patients with primary biliary cirrhosis.
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618
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Di Bisceglie AM, Conjeevaram HS, Fried MW, Sallie R, Park Y, Yurdaydin C, Swain M, Kleiner DE, Mahaney K, Hoofnagle JH. Ribavirin as therapy for chronic hepatitis C. A randomized, double-blind, placebo-controlled trial. Ann Intern Med 1995; 123:897-903. [PMID: 7486483 DOI: 10.7326/0003-4819-123-12-199512150-00001] [Citation(s) in RCA: 260] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
OBJECTIVE To evaluate ribavirin, an oral antiviral agent, as therapy for chronic hepatitis C. DESIGN Randomized, double-blind, placebo-controlled study. SETTING Clinical Center of the National Institutes of Health, a tertiary referral research hospital. PATIENTS 29 patients with chronic hepatitis C who received oral ribavirin (600 mg twice daily) for 12 months and 29 controls with chronic hepatitis C who received placebo for 12 months. MEASUREMENTS Effects of therapy were evaluated by measuring serum aminotransferase and hepatitis C virus (HCV) RNA levels before, during, and for 6 months after therapy and by histologic examination of liver specimens before and at the end of treatment. RESULTS Patients treated with ribavirin had a prompt decrease in serum aminotransferase levels (54% overall) compared with levels before treatment and levels in controls (5% decrease). Serum aminotransferase levels became normal or nearly normal in 10 patients treated with ribavirin (35% [95% CI, 18% to 54%]) but in no controls (0% [CI, 0% to 12%]). Aminotransferase levels remained normal in only 2 patients after ribavirin therapy was discontinued (7% [CI, 1% to 23%]). Serum HCV RNA levels did not change during or after therapy. Liver biopsy specimens showed a decrease in hepatic inflammation and necrosis among ribavirin-treated patients whose aminotransferase levels became normal. CONCLUSIONS Ribavirin has beneficial effects on serum aminotransferase levels and histologic findings in the liver in patients with chronic hepatitis C, but these effects are not accompanied by changes in HCV RNA levels and are not sustained when ribavirin therapy is discontinued. Thus, ribavirin alone for periods as long as 12 months is unlikely to be of value as therapy for chronic hepatitis C.
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619
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Park Y, Adenwalla S, Felcher GP, Bader SD. Superparamagnetic relaxation of Fe deposited on MgO(001). PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:12779-12783. [PMID: 9980444 DOI: 10.1103/physrevb.52.12779] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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620
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Sasamoto S, Haruyama T, Park Y, Okuyama N, Yamazaki S, Komatsu H. [A case of Addison's disease complicated by lung carcinoma treated with surgical resection--a case report]. [ZASSHI] [JOURNAL]. NIHON KYOBU GEKA GAKKAI 1995; 43:1879-83. [PMID: 8522878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Surgery was successful in a 72-year-old man with Addison's disease complicated by right lower lobe carcinoma of the lung. The patient had been diagnosed Addison's disease 25 years earlier and had been treated with cortisone acetate 25 mg every morning. A tumor shadow was found in the right lower lobe of the lung on chest X-ray. Squamous cell carcinoma was diagnosed by cytological examination. Right lower lobectomy with partial resection of the right diaphragma and lymph-node dissection were performed. The bronchial stump was closed using Sweet's method and covered with a pericardial fat pad. The intra- and post-operative course was uneventful with intravenous administration of adequate doses of hydrocortisone. The patient has been free from the carcinoma for two years.
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621
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McKenzie R, Fried MW, Sallie R, Conjeevaram H, Di Bisceglie AM, Park Y, Savarese B, Kleiner D, Tsokos M, Luciano C. Hepatic failure and lactic acidosis due to fialuridine (FIAU), an investigational nucleoside analogue for chronic hepatitis B. N Engl J Med 1995; 333:1099-105. [PMID: 7565947 DOI: 10.1056/nejm199510263331702] [Citation(s) in RCA: 400] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND We describe severe and unexpected multisystem toxicity that occurred during a study of the antiviral nucleoside analogue fialuridine (1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)-5-iodouracil, or FIAU) as therapy for chronic hepatitis B virus infection. METHODS Fifteen patients with chronic hepatitis B were randomly assigned to receive fialuridine at a dose of either 0.10 or 0.25 mg per kilogram of body weight per day for 24 weeks and were monitored every 1 to 2 weeks by means of a physical examination, blood tests, and testing for hepatitis B virus markers. RESULTS During the 13th week lactic acidosis and liver failure suddenly developed in one patient. The study was terminated on an emergency basis, and all treatment with fialuridine was discontinued. Seven patients were found to have severe hepatotoxicity, with progressive lactic acidosis, worsening jaundice, and deteriorating hepatic synthetic function despite the discontinuation of fialuridine. Three other patients had mild hepatotoxicity. Several patients also had pancreatitis, neuropathy, or myopathy. Of the seven patients with severe hepatotoxicity, five died and two survived after liver transplantation. Histologic analysis of liver tissue revealed marked accumulation of microvesicular and macrovesicular fat, with minimal necrosis of hepatocytes or architectural changes. Electron microscopy showed abnormal mitochondria and the accumulation of fat in hepatocytes. CONCLUSIONS In patients with chronic hepatitis B, treatment with fialuridine induced a severe toxic reaction characterized by hepatic failure, lactic acidosis, pancreatitis, neuropathy, and myopathy. This toxic reaction was probably caused by widespread mitochondrial damage and may occur infrequently with other nucleoside analogues.
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Park Y, Ruan F, Hakomori S, Igarashi Y. Cooperative inhibitory effect of n,n,n-trimethylsphingosine and sphingosine-1-phosphate, co-incorporated in liposomes, on b16 melanoma cell metastasis - cell-membrane signaling as a target in cancer-therapy .4. Int J Oncol 1995; 7:487-94. [PMID: 21552864 DOI: 10.3892/ijo.7.3.487] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Two N-methylated derivatives of sphingosine (Sph), N,N-dimethyl-Sph (DMS) and N,N,N-trimethyl-Sph (TMS), have been shown to stereospecifically inhibit activity of protein kinase C and other kinases essential for active proliferation of tumor cells, as well as for activation of platelets and endothelial cells (ECs). DMS and TMS thereby inhibit tumor growth in vivo, and TMS inhibits in vivo metastatic potential of B16 melanoma cells. When TMS was administered in liposomes, its drug efficacy was increased and its undesirable side-effects were greatly reduced (Park YS, er al, Cancer Res 54: 2213, 1994). Sph-1-P, long known as the initial catabolite of Sph metabolism, has aroused considerable interest recently because of its inhibitory effect on cell motility (Sadahira Y, et al, Proc Natl Acad Sci USA 89: 9686, 1992). We now report that liposomes containing both TMS and Sph-1-P, in comparison to liposomes containing TMS or Sph-1-P alone, exert a much stronger inhibitory effect on B16 melanoma cell metastasis. This is ascribable to their inhibitory effect on tumor cell invasiveness through motility inhibition, in conjunction with the previously-observed inhibitory effect of TMS on activation of platelets and ECs. Furthermore, the liposomal formulation resulted in prolonged circulation time of both TMS and Sph-1-P in blood, and consequent higher concentration of these compounds in tumor tissues.
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Conjeevaram HS, Hoofnagle JH, Austin HA, Park Y, Fried MW, Di Bisceglie AM. Long-term outcome of hepatitis B virus-related glomerulonephritis after therapy with interferon alfa. Gastroenterology 1995; 109:540-6. [PMID: 7615204 DOI: 10.1016/0016-5085(95)90343-7] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND & AIMS Glomerulonephritis is an uncommon complication of chronic hepatitis B virus (HBV) infection in adults. A high percentage of patients seem to have short-term response to interferon therapy with improvement of proteinuria. The aim of this study was to assess the long-term response of patients with HBV-related glomerulonephritis to interferon alfa therapy. METHODS All patients with chronic hepatitis B and glomerulonephritis who were treated with interferon alfa at the National Institutes of Health between 1985 and 1993 were assessed. RESULTS Of the 15 patients treated, 8 (53%) had a long-term serological response with sustained loss of serum hepatitis B e antigen and HBV DNA. After 1-7 years of follow-up, all 8 responders have normal serum aminotransferase levels and 5 are hepatitis B surface antigen negative. Seven of the responders also showed a gradual but marked improvement in proteinuria. In contrast, the 7 nonresponders continued to have evidence of active renal disease and 1 required long-term dialysis therapy. All 8 responders had membranous glomerulonephritis, whereas 4 of 7 nonresponders had membranoproliferative glomerulonephritis. CONCLUSIONS Interferon alfa therapy resulted in long-term remission in liver disease in 8 of 15 patients with chronic hepatitis B and glomerulonephritis. This response was accompanied by significant improvement in markers of renal disease in the majority of patients.
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624
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Park Y, Lee H, Koh CS, Min H, Yoo K, Kim Y, Shin Y. Prevalence of diabetes and IGT in Yonchon County, South Korea. Diabetes Care 1995; 18:545-8. [PMID: 7497867 DOI: 10.2337/diacare.18.4.545] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To determine the prevalence of diabetes and impaired glucose tolerance (IGT) in Yonchon County of South Korea and to investigate their associated factors. RESEARCH DESIGN AND METHODS We performed a population-based cross-sectional study with random cluster sampling of residents > or = 30 years of age. Among the 3,804 residents sampled, a total of 2,520 participants had a standard 75-g oral glucose tolerance test and answered a detailed questionnaire. We also collected standard anthropometric data. RESULTS If the data for participants in the age range of 30-64 years were adjusted to the standard world population, the prevalence of diabetes was 7.2% and the prevalence of IGT was 8.9%. It was observed that the significant factors associated with diabetes were waist-to-hip circumference ratio, serum triglyceride levels, age, systolic blood pressure, family history of diabetes, and locality. CONCLUSIONS The prevalence of diabetes in Yonchon County was substantially higher than was previously suggested. The risk of diabetes increased with the increased central obesity and metabolic disturbances associated with insulin resistance.
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625
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Mentnech R, Ross W, Park Y, Benner S. An analysis of utilization and access from the NHIS: 1984-92. HEALTH CARE FINANCING REVIEW 1995; 17:51-9. [PMID: 10157379 PMCID: PMC4193550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
While the aged as a group have better access to health care since the inception of Medicare, there are subsets of the population that are still vulnerable to large out-of-pocket expenses. The focus of this analysis is on those segments of the Medicare population which are particularly vulnerable to access problems due to their personal characteristics. In particular, using data from the National Health Interview Survey (NHIS), this article will focus on the simultaneous influence of personal characteristics, such as insurance status, income, health status, and race on the use of physician services by the elderly population.
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Fried MW, Fong TL, Swain MG, Park Y, Beames MP, Banks SM, Hoofnagle JH, Di Bisceglie AM. Therapy of chronic hepatitis B with a 6-month course of ribavirin. J Hepatol 1994; 21:145-50. [PMID: 7989704 DOI: 10.1016/s0168-8278(05)80387-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Ribavirin is a nucleoside analogue with broad spectrum antiviral activity that has been shown to inhibit viral replication in the woodchuck model of hepatitis B virus infection. We studied the effect of ribavirin on viral replication in 18 patients with chronic hepatitis B who were positive for hepatitis B e antigen. Patients were randomized to receive a 24-week course of oral ribavirin at a dose of either 800, 1000, or 1200 mg/kg per day. All patients completed 24 weeks of treatment and an additional 24 weeks of follow up without significant side effects except for mild, reversible hemolytic anemia. Response to ribavirin was similar among all three dosage groups (p > 0.5); hence the data were pooled and analyzed together. Mean hepatitis B virus DNA levels decreased from 162.7 (95% confidence interval, 106 to 219) pg/ml before treatment to its lowest level of 114.3 (95% confidence interval, 53 to 175) pg/ml at week 20 (p < 0.05). Two patients became negative for HBV DNA and lost hepatitis B e antigen. Mean serum alanine aminotransferase activity decreased markedly from 131.1 (95% confidence interval, 84 to 178) U/l before treatment to 62.4 (95% confidence interval, 48 to 77) U/l at the end of 24 weeks of ribavirin (p < 0.05) and became normal in four patients (22%). Aminotransferase levels returned to baseline within 4 weeks once ribavirin was discontinued, while HBV DNA concentrations remained below baseline even at the end of 24 weeks of follow up.(ABSTRACT TRUNCATED AT 250 WORDS)
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627
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Worley G, Erwin CW, Schuster JM, Park Y, Boyko OB, Griebel ML, Weidman ER, Radtke RA, Oakes WJ. BAEPs in infants with myelomeningocele and later development of Chiari II malformation-related brainstem dysfunction. Dev Med Child Neurol 1994; 36:707-15. [PMID: 8050624 DOI: 10.1111/j.1469-8749.1994.tb11913.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Thirty-seven infants with myelomeningocele received brainstem auditory evoked potentials (BAEPs) at a median age of eight days. No infant had brainstem dysfunction at the time of testing. Median follow-up was at 30 months. Of 12 infants who subsequently developed brainstem dysfunction at a median age of three months, 11 had had abnormal neonatal BAEPs. In contrast, only 10 of 25 infants who did not develop brainstem dysfunction had abnormal BAEPs. The mean average I-V interpeak latencies was greater among those who developed symptoms than among those who did not. Neonatal BAEPs can identify a group of asymptomatic infants with myelomeningocele who need close follow-up for the subsequent development of brainstem dysfunction.
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628
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Chen D, Park Y, Kemper B. Differential protein binding and transcriptional activities of HNF-4 elements in three closely related CYP2C genes. DNA Cell Biol 1994; 13:771-9. [PMID: 7772258 DOI: 10.1089/dna.1994.13.771] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A functional binding site for a liver-enriched transcription factor, hepatocyte nuclear factor-4 (HNF-4), has previously been identified around -100 in the CYP2C2 promoter and proposed to be a common regulatory motif for the hepatic expression of many CYP2 genes. The transcriptional activity of the proximal promoters of three closely related cytochrome P450 genes (CYP2C1, CYP2C2, and CYP2C3) have been compared in HepG2 cells and correlated with the relative binding affinities of the HNF-4 motifs in the genes for proteins in liver, kidney, and HepG2 extracts that react with antisera to HNF-4. Gel-shift assays suggested that these highly similar motifs bound HNF-4 with significantly different affinities. The relative binding affinities to the protein in liver extracts were estimated by competitive gel-shift binding, and the binding affinity of CYP2C2 was two-fold and eight-fold greater than that of CYP2C1 and CYP2C3, respectively. These affinity differences correlated well with the transcriptional activities of either the minimal hepatic promoters (117 to 135 bp of 5'-flanking region) of the genes in HepG2 cells or minimal CYP2C2 promoters containing the HNF-4 motif from each gene. Identification of the CYP2C3 site was somewhat indirect; the HNF-4 element in the CYP2C3 promoter could be converted to a motif with binding affinity and hepatic cell-specific transcriptional activity similar to that of CYP2C2 by a single nucleotide substitution. The activities of the minimal promoters did not correlate well with hepatic expression of each gene in vivo, as estimated previously by the concentration of mRNA in livers of untreated animals.(ABSTRACT TRUNCATED AT 250 WORDS)
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Han K, Hong J, Lim HC, Kim CH, Park Y, Cho JM. Tyrosinase production in recombinant E. coli containing trp promoter and ubiquitin sequence. Ann N Y Acad Sci 1994; 721:30-42. [PMID: 8010680 DOI: 10.1111/j.1749-6632.1994.tb47374.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We have successfully expressed the active tyrosinase of Streptomyces antibioticus in Escherichia coli under the control of the trp promoter by fusing the sequence to the ORF438 gene. Because our attempt to connect the polycistronic gene of ORF438 and tyrosinase directly to the trp promoter of E. coli resulted in the expression of functionally inactive tyrosinase, we decided to fuse the COOH-terminus of ubiquitin sequence to the NH2-terminus of ORF438. Ubiquitin fusion has been shown to augment the yield of cloned gene products in E. coli by increasing the stability or translational efficiency of the fusion proteins. As a result, E. coli transformants harboring a plasmid pTRUBF that contains the ubiquitin-fused ORF438 and the tyrosinase gene produced the strong black pigment of melanin. About 300 units of tyrosinase per liter of batch culture were detected when cultivated in M9 medium containing casamino acids, L-tyrosine, and copper supplements. The black pigment, however, was not seen when grown in LB medium, suggesting that the trp promoter is well regulated. When recombinant E. coli cells grown in LB medium were transferred to a tryptophan-deficient minimal medium with phenol, we observed that phenol was removed from the solution, and the color of the medium turned black. This is due to the fact that the tyrosinase has polyphenol oxidase properties. We expect to use this recombinant E. coli for the waste treatment of phenolic compounds.
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630
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Park Y, Devlin TM, Jones DP. Protection of hepatocytes against death due to mitochondrial failure: effect of di-Calciphor on antimycin A-induced toxicity. Toxicol Appl Pharmacol 1994; 126:33-8. [PMID: 8184430 DOI: 10.1006/taap.1994.1087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Di-Calciphor is a synthetic derivative of prostaglandin B1 that protects against cerebral and cardiac ischemia apparently by preserving mitochondrial function. To determine whether di-Calciphor specifically protects against mitochondrial failure, we studied its effects on mitochondrial functions in hepatocytes treated with the specific mitochondrial poison, antimycin A. The results show that 1 microM di-Calciphor protects against cell death at concentrations of antimycin A that inhibited mitochondrial respiration and caused cellular ATP depletion. Di-Calciphor did not protect against loss of ATP but did protect against the loss of mitochondrial delta psi and delta pH. In addition, di-Calciphor protected against antimycin A-induced loading of phosphate into mitochondria and an associated mitochondrial swelling. Thus, these results show that di-Calciphor protects against a specific mitochondrial poison and support the interpretation that di-Calciphor is a mitochondrial protective agent. In addition, the results suggest that the protection of the mitochondria involves preservation of mitochondrial ionic and osmotic stability and does not involve improved ATP supply.
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Miller CC, Park Y, Pariza MW, Cook ME. Feeding conjugated linoleic acid to animals partially overcomes catabolic responses due to endotoxin injection. Biochem Biophys Res Commun 1994; 198:1107-12. [PMID: 8117267 DOI: 10.1006/bbrc.1994.1157] [Citation(s) in RCA: 238] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The ability of conjugated linoleic acid to prevent endotoxin-induced growth suppression was examined. Mice fed a basal diet or diet with 0.5% fish oil lost twice as much body weight after endotoxin injection than mice fed conjugated linoleic acid. By 72 hours post injection, mice fed conjugated linoleic acid had body weights similar to vehicle injected controls; however, body weights of basal and fish oil fed mice injected with endotoxin were reduced. Conjugated linoleic acid prevented anorexia from endotoxin injection. Splenocyte blastogenesis was increased by conjugated linoleic acid.
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632
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Awad AB, Park Y, Fink CS, Horvath PJ. Influence of dietary fat and feeding period on phosphoinositide metabolism in rat colonocytes. Nutr Cancer 1994; 21:71-81. [PMID: 8183724 DOI: 10.1080/01635589409514305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The objective of the present study was to examine the effect of dietary fat content on phosphoinositide (PI) metabolism, fatty acid composition in colonocytes, and colonic luminal content of bile acids (BA) and free fatty acids (FFA) in rats. Male Sprague-Dawley rats weighing approximately 166 g were fed to semipurified diet containing 3% or 21.5% beef fat and 2% corn oil. The nonfat ingredients were adjusted to correct for differences in food consumption of these diets. Animals were fed these diets ad libitum for one or four weeks. The isolated colonocytes had a viability of 88.9% in all groups. PI metabolism was examined in the absence (basal) or presence of agonists, 2 mM deoxycholic acid or 10 microM A23187. Dietary fat concentration had no effect on PI metabolism, but the length of feeding had a significant effect on basal and stimulated PI metabolism. Colonocytes of animals fed the diets for four weeks were less sensitive to stimulation of PI cycle by agonists than those of animals fed for one week. Colonocyte fatty acid composition was influenced by dietary fat and feeding period. Only the relative percentage of 20:3(n-6) was significantly lower in rats fed the high-fat diet for one week; 18:0 was lower and 18:3(n-6) was higher in colonocytes of animals fed the diets for one week than in those fed for four weeks. Several colonic fatty acids, namely, 16:0, 20:3(n-6), and 22:5(n-6), also exhibited diet-by-feeding period interaction. Intracolonic luminal contents from rats fed the high-fat diet contained elevated concentrations of BA and FFA (44% and 62%, respectively). It was concluded that despite the effects of dietary fat concentration on increased colonic BA and FFA and on altered membrane fatty acid composition, dietary fat had no effect on PI metabolism in colonocytes under the conditions in the present experiment. A difference in components between the purified diet and the commercial rat chow and/or an aging effect of the rats may alter the PI cycle of colonocytes.
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633
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Horsley WS, Whitlark JD, Hall JD, Gott JP, Huang AH, Park Y, Jones DP, Guyton RA. Revascularization for acute regional infarct: superior protection with warm blood cardioplegia. Ann Thorac Surg 1993; 56:1228-37; discussion 1237-8. [PMID: 8267418 DOI: 10.1016/0003-4975(93)90658-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Continuous retrograde warm blood cardioplegia was compared with two widely used hypothermic myocardial protection techniques in a canine model of acute regional myocardial ischemia with subsequent revascularization. Animals (n = 30) underwent 45 minutes of left anterior descending coronary artery occlusion then cardioplegic arrest (60 minutes), followed by separation from cardiopulmonary bypass and data collection. The cold oxygenated crystalloid cardioplegia group (CC; n = 8) and the cold blood cardioplegia group (CC; n = 10) had cardiopulmonary bypass at 28 degrees C, antegrade arrest, and intermittent retrograde delivery. The warm blood cardioplegia group (WB; n = 12) had normothermic cardiopulmonary bypass, antegrade arrest, and continuous retrograde delivery. Overall ventricular function (preload recruitable stroke work relationship; ergs x 10(3)/mL) was significantly (p < 0.001) better for WB (WB, 80 +/- 11; CB, 67 +/- 13; CC, 57 +/- 12). Systolic function (maximum elastance relationship; mm Hg/mL) was also significantly (p < 0.001) better for WB (WB, 11.6 +/- 3.6; CB, 8.6 +/- 2.7; CC, 6.2 +/- 1.3). Diastolic function (stress-strain relationship; dynes x 10(3)/cm2) revealed significantly (p < 0.001) decreased compliance for CC (WB, 20 +/- 6; CB, 19 +/- 7; CC, 27 +/- 11). Left anterior descending coronary artery regional adenosine triphosphate/adenosine diphosphate ratios were significantly (p = 0.02) worse for CC (WB, 10.2 +/- 2.3; CB, 9.4 +/- 2.6; CC, 5.6 +/- 1.5). Myocardial edema significantly (p = 0.03) increased over time only in the CC animals (WB, 0.4% +/- 2.3%; CB, -0.3% +/- 3.6%; CC, 5.5% +/- 2.3%). In this model of acute regional myocardial ischemia and revascularization, continuous retrograde warm aerobic blood cardioplegia provided superior myocardial protection compared with cold oxygenated crystalloid cardioplegia with intermediate results for cold blood cardioplegia.
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634
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Park Y, Gong G, Choe G, Yu E, Kim KS, Lee I. Jarcho-Levin syndrome--a report of an autopsy case with cytogenetic analysis. J Korean Med Sci 1993; 8:471-5. [PMID: 8179836 PMCID: PMC3053874 DOI: 10.3346/jkms.1993.8.6.471] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Jarcho-Levin syndrome (JLS) is a condition manifested by malformations of vertebral bodes and related ribs. There are two major subtypes spondylocostal dysostosis and spondylothoracic dysostosis, with different survival rates, associated malformations, and inheritance patterns. We have experienced an autopsy case of a premature female fetus with multiple congenital anomalies. She was 30 weeks of gestational age, born as the second baby of twins and expired shortly after birth. A post-mortem examination revealed multiple abnormalities including cervicothoracic hemivertebrae, a diminished number of right-sided ribs, and pulmonary hypoplasia with left diaphragmatic hernia. In addition, there were anomalous rotation of the foregut, unfused pancreas and anomalous drainage of the superior vena cava. Chromosomal analysis showed 46, XX, del(4)(q ter).
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635
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Hashimoto K, Kishima Y, Onishi N, Esa A, Sugiyama T, Park Y, Kohri K, Akiyama T, Kurita T. [Transurethral teflon paste injection for vesicoureteral reflux in neurogenic bladder dysfunction]. Nihon Hinyokika Gakkai Zasshi 1993; 84:2118-23. [PMID: 8309118 DOI: 10.5980/jpnjurol1989.84.2118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We experienced transurethral teflon paste injection for 12 refluxing ureters of 7 patients with neurogenic bladder dysfunction. Preoperative assessment of cystometry showed hypoactive bladder function with normal bladder compliance in 4 patients, and low compliance bladder (< 10 ml/cmH2O) in 1. Voiding cystography revealed grade 1 reflux in 2 ureters, grade 2 in 3, grade 3 in 2, grade 4 in 2, and grade 5 in 2. One ureter did not show reflux. Zero point two to 1.6 ml of teflon paste was injected on each ureter under cystoscopic observation. These patients were followed for a mean of 25.1 months. Reflux disappeared immediately after the first operations in all patients, however recurrence was observed in 2 ureters, in which improvement of reflux (grade 5 to 2) was achieved in 1 ureter but no improvement (grade 2 to 2) in another. Pyelonephritis was not encountered in any patients after injection. No complication was observed through the follow up period. In conclusion, we advocate that endoscopic teflon paste injection is a useful alternative to ureteroneocystostomy in the treatment of reflux in patients with neurogenic bladder dysfunction.
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636
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Kang K, Oh JH, Kwon C, Park Y. Generalization in a two-layer neural network. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1993; 48:4805-4809. [PMID: 9961164 DOI: 10.1103/physreve.48.4805] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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637
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Nelson WM, Park Y. N=2 supersymmetry in two-dimensional dilaton gravity. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1993; 48:4708-4712. [PMID: 10016124 DOI: 10.1103/physrevd.48.4708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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638
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Di Bisceglie AM, Fong TL, Fried MW, Swain MG, Baker B, Korenman J, Bergasa NV, Waggoner JG, Park Y, Hoofnagle JH. A randomized, controlled trial of recombinant alpha-interferon therapy for chronic hepatitis B. Am J Gastroenterol 1993; 88:1887-92. [PMID: 8237937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES To evaluate the effect of recombinant alpha-interferon in chronic hepatitis B. METHODS Patients were stratified at entry according to their serum aspartate aminotransferase (AST) values, randomized to receive alpha-interferon (alfa-2b, 10 million units three times weekly) or to be untreated controls for 16 wk. Effect of therapy on levels of hepatitis B viral (HBV) DNA and aminotransferase activities in serum and hepatitis B e antigen (HBeAg) status was monitored. RESULTS Forty-seven patients entered the trial; 11 of 25 (44%) patients receiving interferon responded by clearing HBeAg and HBV DNA within 6 months, compared to one of 22 (5%) controls (p < 0.05). Among those with serum AST values < 100 U/L, 33% responded and among those with AST values > 100 U/L, 60% responded. Within the 6-month study period, 36% of treated patients had normal serum alanine aminotransferase (ALT) values, and 16% had cleared hepatitis B surface antigen (HBsAg) from serum, whereas none of the controls had normal ALT values or had lost HBsAg. Interferon was stopped early in three patients (6.5%), and dosage was reduced in a further 16 patients (35%) because of adverse effects. Predictive factors for a response were the pretreatment serum ALT and AST activities. CONCLUSIONS alpha-Interferon therapy (three times weekly) is relatively well tolerated and is effective in clearing HBeAg and HBV DNA in approximately one-third of treated patients.
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639
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Park Y, McBride BC. Characterization of the tpr gene product and isolation of a specific protease-deficient mutant of Porphyromonas gingivalis W83. Infect Immun 1993; 61:4139-46. [PMID: 8406803 PMCID: PMC281136 DOI: 10.1128/iai.61.10.4139-4146.1993] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The previously described protease gene (tpr) of Porphyromonas gingivalis W83 was shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the recombinant protein and in vitro translation to encode a 50-kDa protein whose active form migrates with an apparent molecular mass of 90 kDa. The 50-kDa protein was expressed at high levels by using a T7 RNA polymerase/promoter system. The NH2-terminal sequence of the protein was identical to the amino acid sequence deduced from the DNA sequence of the protease gene. Affinity-purified antibody to the 90-kDa recombinant protease reacted with an 80-kDa P. gingivalis protein. A specific protease (Tpr)-deficient isogenic mutant of P. gingivalis was generated by homologous recombination between P. gingivalis chromosomal DNA and a suicide plasmid carrying the cloned gene disrupted by insertion of an erythromycin resistance gene. Gelatin substrate zymography showed that cell extracts of the mutant lacked a protease band that migrated with an apparent molecular mass of 80 kDa. Western immunoblots of the cell extracts indicated the loss of an antigen with a similar mass.
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640
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Cook ME, Miller CC, Park Y, Pariza M. Immune modulation by altered nutrient metabolism: nutritional control of immune-induced growth depression. Poult Sci 1993; 72:1301-5. [PMID: 8346156 DOI: 10.3382/ps.0721301] [Citation(s) in RCA: 323] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The ability of conjugated isomers of linoleic acid (CLA) to prevent reduced growth rate following endotoxin (lipopolysaccharide, LPS) injection was studied in two chick trials and one rat trial. Chicks (10 per treatment) were fed a corn and soybean meal-based diet with or without .5% CLA. At 21 days of age, chicks were weighed and injected i.p. with 1 mg/kg BW Escherichia coli LPS and sterile PBS. Body weights were again determined 24 h later. Antibody responses to SRBC were also determined. Rats fed .5% stearic acid or CLA for 4 wk (seven per treatment) were also injected with LPS, and BW change over a 24-h postinjection period was determined. Antibody responses to BSA, phytohemagglutinin foot pad swelling, and phagocytosis of elicited peritoneal macrophages were also determined. The CLA had no adverse effects on any immune variables measured in the chicks and rats. The CLA enhanced the phytohemagglutinin response and macrophage phagocytosis in rats. Chicks fed CLA and injected with LPS continued to grow, whereas those not fed CLA either failed to grow or lost weight following LPS injection. Both control and CLA-fed rats lost weight over the 24-h period after LPS injection; however, the loss of weight in rats fed CLA was only half of the weight loss of the control rats. Thus, CLA is effective in preventing the catabolic effects of immune stimulation.
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Kwon C, Park Y, Oh J. Stability of the replica-symmetric solution for a perceptron learning from examples. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1993; 47:3707-3711. [PMID: 9960426 DOI: 10.1103/physreve.47.3707] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Hoofnagle JH, Di Bisceglie AM, Waggoner JG, Park Y. Interferon alfa for patients with clinically apparent cirrhosis due to chronic hepatitis B. Gastroenterology 1993; 104:1116-21. [PMID: 8462800 DOI: 10.1016/0016-5085(93)90281-g] [Citation(s) in RCA: 143] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND The prognosis of advanced cirrhosis due to chronic hepatitis B is poor, and results of therapies, including liver transplantation, have been unsatisfactory. Little is known about the effectiveness of interferon alfa in patients with cirrhosis. METHODS Between 1984 and 1991, 18 patients with clinically-apparent cirrhosis due to hepatitis B were treated with interferon alfa at the Clinical Center of the National Institutes of Health. RESULTS Six treated patients (33%) had a sustained loss of hepatitis B virus DNA and hepatitis B e antigen (if present initially) and decrease of amino-transferase levels into the normal or near normal range. In follow-up, these 6 patients resolved all symptoms of cirrhosis and are alive and fully active. In contrast, the 12 patients who did not have a sustained loss of hepatitis B virus have had evidence of progressive liver disease, 6 have died and 4 underwent hepatic transplantation. Side effects of interferon were common and included bacterial infections (n = 5) and exacerbations of disease (n = 9). CONCLUSIONS These findings indicate that interferon alfa is effective in selected patients with mildly decompensated cirrhosis due to hepatitis B.
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643
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Park Y, Strominger A. Supersymmetry and positive energy in classical and quantum two-dimensional dilaton gravity. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1993; 47:1569-1575. [PMID: 10015734 DOI: 10.1103/physrevd.47.1569] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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644
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Fried MW, Korenman JC, Di Bisceglie AM, Park Y, Waggoner JG, Mitsuya H, Hartman NR, Yarchoan R, Broder S, Hoofnagle JH. A pilot study of 2',3'-dideoxyinosine for the treatment of chronic hepatitis B. Hepatology 1992; 16:861-4. [PMID: 1398494 DOI: 10.1002/hep.1840160402] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The nucleoside analog 2',3'-dideoxyinosine, currently being used to treat patients infected with the human immunodeficiency virus, has been shown to inhibit viral replication in certain cell culture systems of hepatitis B virus and the duck model of chronic hepatitis B infection. We studied the effect of dideoxyinosine on viral replication in patients with chronic hepatitis B. In the initial dose-finding phase, patients received sequential 2-wk courses of dideoxyinosine in escalating doses of 3, 6 and 9 mg/kg/day. In the second, long-term treatment phase, patients received dideoxyinosine at a dose of 9 mg/kg/day for 12 wk. Dideoxyinosine was given orally in three divided doses. The effects of dideoxyinosine on hepatitis B were assessed by serial measurements of ALT, hepatitis B virus DNA and DNA polymerase activity in serum. Six patients completed the dose-finding phase, and five patients continued into the long-term treatment phase. No significant differences were seen in serum aminotransferases, hepatitis B virus DNA levels or DNA polymerase activity at any time during treatment when compared with pretreatment levels. All patients remained positive for HBeAg during treatment and during 6 mo of follow-up. Thus at the doses tested, dideoxyinosine had no appreciable effect on viral replication in patients with chronic hepatitis B.
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Di Bisceglie AM, Shindo M, Fong TL, Fried MW, Swain MG, Bergasa NV, Axiotis CA, Waggoner JG, Park Y, Hoofnagle JH. A pilot study of ribavirin therapy for chronic hepatitis C. Hepatology 1992; 16:649-54. [PMID: 1505907 DOI: 10.1002/hep.1840160307] [Citation(s) in RCA: 215] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Interferon-alpha therapy is of proven efficacy in chronic hepatitis C, but it is not universally effective and may be associated with intolerable side effects. Ribavirin is a nucleoside analog with a broad spectrum of antiviral action. We conducted an uncontrolled pilot study of ribavirin therapy in 13 patients with chronic hepatitis C. Ribavirin was given for 6 mo, in a dose that was increased, at 2-mo intervals, from 600 mg to 1,000 mg to 1,200 mg/day. Serum ALT levels gradually decreased in all 13 treated patients; the mean percentage of decrease was 67% (from 210 U/L [range = 109 to 593] to 63 U/L [range = 22 to 108 U/L]; p = 0.0006) after 6 mo of treatment. Serum aminotransferase levels fell to the normal range in four patients (31%). In the 3 to 6 mo after cessation of ribavirin therapy, serum aminotransferase activities gradually rose to near pretreatment levels in all but one patient. Therapy was associated with a significant decrease in the geometric mean titer of hepatitis C virus RNA in serum (1:1,981 vs. 1:199; p less than 0.02) although no patients lost hepatitis C virus RNA from serum during therapy. No significant improvement was seen in liver histological appearance. Ribavirin therapy resulted in mild, reversible hemolysis; no patient exhibited symptomatic anemia. These findings suggest that ribavirin has a beneficial effect in patients with chronic hepatitis C, although further studies are needed to determine how ribavirin is best used.
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Park Y, Devlin TM, Jones DP. Protective effect of the dimer of 16,16-diMePGB1 against KCN-induced mitochondrial failure in hepatocytes. THE AMERICAN JOURNAL OF PHYSIOLOGY 1992; 263:C405-11. [PMID: 1514587 DOI: 10.1152/ajpcell.1992.263.2.c405] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The dimer and trimer of 16,16-dimethyl-15-dehydroprostaglandin B1 (16,16-diMePGB1) previously have been shown to have protective effects on mitochondrial function. To examine the potential mechanisms involved in protection against mitochondrial failure, we have studied the effects of the dimer of 16,16-diMe-PGB1 (dicalciphor) on mitochondrial function in hepatocytes exposed to KCN. Addition of micromolar concentrations of dicalciphor provided substantial protection against KCN-induced toxicity in a concentration- and time-dependent manner. Dicalciphor, however, had no effect on total or mitochondrial ATP losses in KCN-treated cells. The dimer prevented the marked loss of mitochondrial membrane potential (delta psi) and delta pH that occurs as a result of KCN treatment and prevented KCN-induced loading of phosphate in mitochondria. Furthermore, the dimer of 16,16-diMePGB1 also prevented KCN-induced mitochondrial and cellular swelling. These results demonstrate that dicalciphor protects against KCN-induced damage and that this protection is associated with regulation of specific mitochondrial ion transport functions.
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D'Agostino HB, Park Y, Moyers JP, vanSonnenberg E, Sanchez RB, Goodacre BW, Kim YH, Vieira MV. Influence of the stopcock on the efficiency of percutaneous drainage catheters: laboratory evaluation. AJR Am J Roentgenol 1992; 159:407-9. [PMID: 1632367 DOI: 10.2214/ajr.159.2.1632367] [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: 12/28/2022]
Abstract
The effects of stopcocks on percutaneous fluid drainage were tested in a laboratory model by using a standard stopcock (6-French inner diameter) and a prototype stopcock (9-French inner diameter) connected to 8-, 10-, 12-, 14-, and 16-French catheters. Catheters were immersed in water alone or in viscous fluid with particulate matter, and the system was connected to low wall suction or gravity drainage. The average volume of fluid aspirated in a given period with and without a stopcock was compared for each catheter. The standard stopcock decreased drainage efficiency for these catheters by 13-42%. This decreased drainage efficiency was worse with the larger catheters. Particulate fluid blocked the stopcock connection for all catheters. With the prototype stopcock, drainage of water alone was reduced by 0-9% for the catheters of different sizes. Particulate fluid did not obstruct the prototype stopcock with any size catheter. With gravity drainage, the volume of water aspirated was reduced by 12-42% with the standard stopcock and by 3-6% with the prototype stopcock. These data suggest that stopcock connections greatly influence the efficiency of the percutaneous drainage systems. Stopcocks with larger inner diameters may improve drainage over that achievable with the stopcocks that are currently available.
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649
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Park Y, McBride BC. Cloning of a Porphyromonas (Bacteroides) gingivalis protease gene and characterization of its product. FEMS Microbiol Lett 1992; 71:273-8. [PMID: 1320588 DOI: 10.1016/0378-1097(92)90721-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A clone expressing a Porphyromonas gingivalis protease from the recombinant plasmid (pYS307) has been identified in a genomic library of P. gingivalis W83. The cloned gene was localized to a 2.4-kb DNA fragment between BamHI and HindIII sites. When a 3.2-kb HindIII fragment of pYS307 was used as a probe in Southern hybridization, HindIII-digested chromosomal DNA of P. gingivalis W83, as well as those of W50 and W12, showed a single 3.2-kb hybridizing band, while that of P. gingivalis 33277 showed a 5.0-kb band. Colonies of E. coli containing pYS307 showed pronounced proteolytic zones on skim milk agar plates only when incubated in an oxygen-free environment. BSA substrate zymography of whole cell extract of E. coli containing pYS307 revealed a protease of approx. 80 kDa which was active under reducing conditions. These results suggest that the cloned protease is thiol-dependent. Antiserum to P. gingivalis W50 reacted with a single band of 80 kDa when a cell lysate sample of an E. coli JM83 containing pYS307 was prepared for electrophoresis in the absence of beta-mercaptoethanol. When samples were solubilized in the presence of beta-mercaptoethanol prior to electrophoresis, the antiserum reacted with the bands of 50 and 38 kDa, but there was no reaction observed at 80 kDa. The activity of the cloned protease was inhibited by TLCK, TPCK, EDTA, PMSF, iodoacetic acid and ZnCl2.
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Bergasa NV, Talbot TL, Alling DW, Schmitt JM, Walker EC, Baker BL, Korenman JC, Park Y, Hoofnagle JH, Jones EA. A controlled trial of naloxone infusions for the pruritus of chronic cholestasis. Gastroenterology 1992; 102:544-9. [PMID: 1732125 DOI: 10.1016/0016-5085(92)90102-5] [Citation(s) in RCA: 182] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
To test the hypothesis that opioid agonist activity contributes to the pruritus of cholestasis, a placebo-controlled single-blinded trial of naloxone, an opioid antagonist, was conducted in eight patients with primary biliary cirrhosis. After discontinuation of all conventional antipruritic medications, one or two continuous (24-hour) IV infusions of naloxone (0.2 micrograms.kg-1.min-1) and placebo solution were administered consecutively in an order that was not predetermined. Pruritus was assessed subjectively by means of four hourly recordings of a visual analogue score. In addition, objective measurements of scratching activity that were independent of gross body movements were continuously recorded using an apparatus specifically designed to measure the frequencies associated with this activity. No side effects associated with naloxone infusions were observed. Only scratching activity data obtained for the same periods of day and night during both naloxone and placebo infusions were compared. Naloxone infusions were consistently associated with a decrease in values of the scratching activity index. In addition, in 50% of the patients the infusions were associated with a decrease in visual analogue score. The mean decrease in scratching activity ranged from 29% to 96% (mean, 50%; P less than 0.001). These findings imply that increased opioid agonist activity contributes to scratching activity in cholestatic patients.
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