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Wada T, Orphanides G, Hasegawa J, Kim DK, Shima D, Yamaguchi Y, Fukuda A, Hisatake K, Oh S, Reinberg D, Handa H. FACT relieves DSIF/NELF-mediated inhibition of transcriptional elongation and reveals functional differences between P-TEFb and TFIIH. Mol Cell 2000; 5:1067-72. [PMID: 10912001 DOI: 10.1016/s1097-2765(00)80272-5] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report that the chromatin-specific transcription elongation factor FACT functions in conjunction with the RNA polymerase II CTD kinase P-TEFb to alleviate transcription inhibition by DSIF (DRB sensitivity-inducing factor) and NELF (negative elongation factor). We find that the kinase activity of TFIIH is dispensable for this activity, demonstrating that TFIIH-mediated CTD phosphorylation is not involved in the regulation of FACT and DSIF/NELF activities. Thus, we propose a novel transcriptional regulatory network in which DSIF/NELF inhibition of transcription is prevented by P-TEFb in cooperation with FACT. This study uncovers a novel role for FACT in the regulation of transcription on naked DNA that is independent of its activities on chromatin templates. In addition, this study reveals functional differences between P-TEFb and TFIIH in the regulation of transcription.
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Kim DK, Kim SC, Chang SN, Kim SY. Epidermolysis bullosa simplex (Dowling-Meara type) associated with pyloric atresia and congenital urologic abnormalities. Yonsei Med J 2000; 41:411-5. [PMID: 10957900 DOI: 10.3349/ymj.2000.41.3.411] [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: 11/27/2022] Open
Abstract
We report a case of epidermolysis bullosa simplex, Dowling-Meara type (EBS-DM), which was associated with congenital pyloric atresia (PA) and various urologic abnormalities, a diagnosis confirmed by immunofluorescence mapping and electron microscopic findings. Immunofluorescent mapping showed the serum from a patient with bullous pemphigoid faintly binding to the floor of the blister, and monoclonal antibodies against type IV and VII collagens were also stained on the floor of the blister. Electron microscopy showed epidermolytic cleavage and prominent clumping of tonofilaments in the basal and suprabasal keratinocytes. An abdominal radiograph and barium swallow showed a complete obstruction at the pyloric channel level. The widespread bullae healed without any scar formation and the bullae formation was localized on the extremities after 3 months of age without any specific treatment. Multiple urologic abnormalities such as bilateral hydronephrosis, hydroureter and a distended bladder with trabeculation were observed at 12 months of age. Currently, with the patient at 4 years of age, bullae still appear on the hands and feet and nail shedding can be observed. The patient's father, a paternal uncle and a paternal aunt had had similar bullous eruptions in infancy, all of which had improved spontaneously by the age of one.
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Cho SW, Cho Y, Kim DK, Shin W. cis-[(4R,5R)-4,5-bis(aminomethyl)-2,2-dimethyl-1,3-dioxolane-N,N']- (malonato-O,O')platinum(II), an anticancer agent. Acta Crystallogr C 2000; 56:653-4. [PMID: 10902008 DOI: 10.1107/s0108270100003577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2000] [Accepted: 03/07/2000] [Indexed: 11/11/2022] Open
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Ahn SH, Han KH, Park JY, Lee CK, Kang SW, Chon CY, Kim YS, Park K, Kim DK, Moon YM. Association between hepatitis B virus infection and HLA-DR type in Korea. Hepatology 2000; 31:1371-3. [PMID: 10827165 DOI: 10.1053/jhep.2000.7988] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Although the mechanism of susceptibility to chronic persistent hepatitis B virus (HBV) infection is not well clarified, immunogenetic factors of the host may have a role. Recently, a strong association between HLA-DR13 and the self-limited course of HBV infection has been reported. To determine whether the elimination of HBV is related to a particular HLA allele, we studied the HBV markers and HLA-DR phenotypes of 1,272 Koreans who had visited Yonsei University Medical Center for renal transplantation. They included 330 renal transplant donors. Subjects were categorized into 3 different groups: the "Unexposed Group" (UE; n = 946) with negative HBV markers, the "Chronic Carrier Group" (CC; n = 83), who were hepatitis B surface antigen (HBsAg)-positive, and the "Spontaneously Cleared Group" (SC; n = 243), who were HBsAg-negative with antibodies to HBsAg (anti-HBs) and hepatitis B core antigen (anti-HBc). HLA-DR4 was the most common type in all groups. HLA-DR6 was significantly more frequent in 69 of 243 subjects with SC (28. 4%) than in 8 of 83 subjects with CC (9.6%) (P <.001; relative risk [RR] = 3.72). HLA-DR9 was significantly more frequent in CC than in SC (P <.001; RR = 0.33). HLA-DR13 showed a stronger association with the clearance of HBV than the other HLA-DR6 subgroup. The distribution of HLA-DR phenotypes was similar regardless of renal disease. Our data indicate that HLA-DR6, especially HLA-DR13, is one of the host factors, which influences the immune response to HBV, and may be associated with self-elimination of HBV in Koreans.
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Lee Y, Park EJ, Yu SS, Kim DK, Kim S. Improved expression of vascular endothelial growth factor by naked DNA in mouse skeletal muscles: implication for gene therapy of ischemic diseases. Biochem Biophys Res Commun 2000; 272:230-5. [PMID: 10872832 DOI: 10.1006/bbrc.2000.2758] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have constructed an expression vector, pCK, that is able to drive high levels of gene expression in the skeletal muscles of mice. pCK contains not only the full length immediate-early (IE) promoter of human cytomegalovirus but also its entire 5' untranslated region upstream from the start codon of the IE gene. In addition, pCK contains the kanamycin resistance gene, but lacks nucleotide sequences unnecessary for its function as a gene delivery vector, allowing the plasmid size to be 3.7 kb. pCK produced significantly higher levels of vascular endothelial growth factor 165 both in vitro and in vivo than the control vector, the structure of which is similar to naked DNA vectors employed in previous gene therapy trials. pCK would not only significantly increase the therapeutic effects of naked DNA gene therapy but also dramatically cut down the costs for production and treatment.
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Kim DK, Cho ES, Um HD. Caspase-dependent and -independent events in apoptosis induced by hydrogen peroxide. Exp Cell Res 2000; 257:82-8. [PMID: 10854056 DOI: 10.1006/excr.2000.4868] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To define the role of caspase-3 in H2O2-induced apoptosis, we introduced caspase-3 cDNA into MCF-7 breast carcinoma cells that otherwise lack caspase-3 expression. H2O2 treatment induced DNA fragmentation and nuclear condensation in the caspase-3-expressing cells, but not in the caspase-3-deficient cells. This indicated that caspase-3 is essential for nuclear events. However, H2O2 induced an externalization of membrane phosphatidylserine (PS) and cell death regardless of caspase-3 expression. These events were not suppressed by Ac-DEVD-CHO and Z-VAD-fmk, which inhibit DEVD-specific caspases and a broad spectrum of caspases, respectively. In Jurkat T cells, these inhibitors abolished H2O2-induced PS relocalization, but not cell death. Therefore, caspases appear to be dispensable for lethality by H2O2, but required for PS redistribution in a cell-type-specific manner.
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Byun J, Kim SH, Kim SZ, Heard JM, Huh JE, Choe YH, Park SJ, Jung EA, Kim DK. Ectopic expression of active processed form of atrial natriuretic peptide in skeletal myoblasts. Biochem Biophys Res Commun 2000; 270:637-42. [PMID: 10753676 DOI: 10.1006/bbrc.2000.2468] [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: 11/22/2022]
Abstract
Atrial natriuretic peptide (ANP) is a cardiac hormone that elicits a profound diuresis, natriuresis, and hypotension. As a preliminary study toward ANP gene therapy of cardiovascular disorders, we have cloned a cDNA for mouse preproANP and carried out expression studies in muscle cells. The expression cassette, which was flanked by ITRs from AAV-2, consisted of HCMV IE enhancer/promoter, preproANP gene, and polyadenylation signal from bovine growth hormone. We transfected this expression vector into primary skeletal myoblasts and examined the following points: (1) secretion of immunoreactive ANP, (2) biological activity, and (3) nature of secreted ANP(s). The conditioned media from cells transfected with ANP vector had significantly higher levels of irANP in comparison to mock control. The secreted irANP had biological activity as confirmed by the elevated level of intracellular cGMP in human umbilical vein endothelial cells. Reverse-phase HPLC analysis showed that the processed form of ANP was the predominant form. These results demonstrate that preproANP gene could be ectopically expressed and correctly processed in skeletal myoblasts, which has implications for development of muscle-based ANP gene therapy.
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Kim WH, Ghil KC, Lee JH, Yeo SH, Chun YJ, Choi KH, Kim DK, Kim MY. Involvement of p27(kip1) in ceramide-mediated apoptosis in HL-60 cells. Cancer Lett 2000; 151:39-48. [PMID: 10766421 DOI: 10.1016/s0304-3835(99)00402-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ceramide acts as a mediator of apoptosis in various cell lines, but little is known regarding the molecular mechanism linked to the cell cycle. In the present study, we examined the expression of p27(kip1) and its relationship to apoptosis induced by ceramide. We demonstrated that treatment of HL-60 cells with C6-ceramide resulted in G1 phase elevation followed by apoptotic cleavage associated with increase in the level of cdk inhibitor p27(kip1). Ceramide inhibited the kinase activities of cdk2 and cdk4 within 24 h of treatment. Ceramide-induced inhibition of cdk2 and cdk4 kinase activities was accompanied by increase of p27(kip1) in the cdks complexes. In addition, we have shown that both the cell death and expression of p27(kip1) protein induced by ceramide were significantly decreased in HL-60 cells overexpressing bcl-2. Furthermore, ceramide induced a significant increase in Bax protein expression coincided with increase in p27(kip1) protein level. These findings indicate that p27(kip1) may play important roles in mediating ceramide-induced apoptosis and its expression can be regulated by Bax and Bcl-2.
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Ryu KH, Rhee HI, Jung I, Kim TS, Lee SJ, Im GJ, Lee N, Ryu DH, Kim YW, Kim JJ, Chang K, Lee BH, Shin HS, Kim EJ, Kim KH, Kim DK. General pharmacology of the new antiviral agent SK 1899. ARZNEIMITTEL-FORSCHUNG 2000; 50:395-403. [PMID: 10800640 DOI: 10.1055/s-0031-1300220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The general pharmacological properties of 2-amino-9-(3-acetoxymethyl-4-isopropoxycarbonyloxybut-1-yl)purine (CAS 247081-81-8, SK 1899), a new potential antiviral agent, were investigated in mice, rats, guinea pigs, rabbits, and dogs. The oral administration of 50, 150, and 500 mg/kg of SK 1899 had no effects on the central nervous system except that it slightly increased the spontaneous locomotor activity in mice at a dose of 500 mg/kg. SK 1899 did not disturb either the spontaneous motility or contractor-induced contraction of the isolated organs such as guinea pig ileum, rat uterus, guinea pig vas deferens, and guinea pig trachea at concentrations up to 10(-4) mol/l. It slightly increased the contractile force in the isolated guinea pig atrium at a concentration of 10(-4) mol/l. Following intravenous infusion of 5, 15, and 50 mg/kg of SK 1899 to anesthetized dogs, it did not change the mean arterial pressure, heart rate, left ventricular systolic pressure (LVSP), and respiratory rate, while it slightly increased the left ventricular positive dP/dtmax (LV + dP/dtmax) at a dose of 50 mg/kg. SK 1899 did not induce any significant changes in the intestinal charcoal meal transit in mice, basal gastric juice secretion in rats, and renal function in rats. It did not affect the blood coagulation system and phenolsulfonphthalein secretion in rats. These findings suggest that SK 1899 has a very low potential to induce any adverse pharmacological effects at the doses showing antiviral activity.
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Rhyu MR, Kim DK, Kim HY, Kim BK. Nitric oxide-mediated endothelium-dependent relaxation of rat thoracic aorta induced by aqueous extract of red rice fermented with Monascus ruber. JOURNAL OF ETHNOPHARMACOLOGY 2000; 70:29-34. [PMID: 10720786 DOI: 10.1016/s0378-8741(99)00132-4] [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
Vasodilatory effects of aqueous extract of red rice fermented with Monascus ruber IFO32318 were examined on the isolated rat aorta. The water phase of fermented rice with Monascus (WP/FRM, 0.1-10 mg/ml) caused a transient relaxation of the endothelium-intact rat aorta precontracted with norepinephrine (NE, 300 nM). The WP/FRM-induced relaxation was abolished by removal of endothelium or in the presence of N(G)-nitro-L-arginine (L-NNA, 10 microM), a nitric oxide (NO) synthase inhibitor. Neither atropine, a muscarinic receptor antagonist (10 microM), nor indomethacin, a cyclooxygenase inhibitor (10 microM), altered the WP/FRM-induced endothelium-dependent relaxation. gamma-Aminobutyric acid (GABA), one of the principle components of the extract, did not affect the muscle tension of the aorta with intact endothelium. In addition, WP/FRM increased the production of NO in primary cultured endothelial cells from human umbilical vein. The enhanced production of NO by WP/FRM was diminished by pretreatment with L-NNA (10 microM). In conclusion, WP/FRM induces relaxation of rat aorta by releasing NO from endothelium. There seem to be some unknown factor(s) other than acetylcholine (Ach) and GABA, in the aqueous extract of red rice, which stimulate vascular endothelial cells to produce and/or release NO leading to endothelium-dependent relaxation by WP/FRM.
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Lee TV, Kim DK, Peoples GE, Castilleja A, Murray JL, Gershenson DM, Ioannides CG. Secretion of CXC chemokine IP-10 by peripheral blood mononuclear cells from healthy donors and breast cancer patients stimulated with HER-2 peptides. J Interferon Cytokine Res 2000; 20:391-401. [PMID: 10805374 DOI: 10.1089/107999000312333] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
CXC chemokines play an important role in recruitment of T cells to the site of activation and regulation of angiogenesis. CXC chemokines are secreted by T cells stimulated with cytokines or by established cytotoxic T lymphocyte (CTL) lines at recognition of conventional antigen (Ag), but the activation requirements and the relationship of interferon-gamma (IFN-gamma) inducible protein (IP-10) secretion with IFN-gamma induction in lymphocytes are still unclear. We studied the induction of IP-10 from nonadherent peripheral blood mononuclear cells (PBMC) by IFN-gamma, interleukin-12 (IL-12), and the HER-2 peptide E75, which forms a CTL-defined antigen. We found that IFN-gamma alone was a weak inducer of IP-10 in these cells, whereas IL-12 was a significantly stronger inducer of IP-10. In the presence of IL-12, the tumor peptide E75 (HER-2, 369-377) was a stronger inducer of IP-10 than was IL-12 alone. E75 and its variants mutated at position 5 could also induce IP-10 in the absence of exogenous IL-12 or IFN-gamma. IP-10 induction by E75 required HLA-A2 presentation and B7-CD28 interactions and was partially inhibited by blocking of CD40-CD40L interactions. These results indicate that presentation of tumor peptides to peripheral T cells can induce a fast chemokine response, which in its early phase may be higher than the IFN-gamma response. This shows that the IP-10 response was independent of any early-phase IFN-gamma response in peripheral T cells. This may be important for understanding the regulation of the balance between chemoattractant chemokines (CC) and CXC chemokines by tumor Ag and may have implications for understanding the mechanisms of polarization of T cells and conditioning of antigen-presenting cells (APC) by tumor antigens.
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Fukasawa Y, Segawa H, Kim JY, Chairoungdua A, Kim DK, Matsuo H, Cha SH, Endou H, Kanai Y. Identification and characterization of a Na(+)-independent neutral amino acid transporter that associates with the 4F2 heavy chain and exhibits substrate selectivity for small neutral D- and L-amino acids. J Biol Chem 2000; 275:9690-8. [PMID: 10734121 DOI: 10.1074/jbc.275.13.9690] [Citation(s) in RCA: 214] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A cDNA was isolated from the mouse brain that encodes a novel Na(+)-independent neutral amino acid transporter. The encoded protein, designated as Asc-1 (asc-type amino acid transporter 1), was found to be structurally related to recently identified mammalian amino acid transporters for the transport systems L, y(+)L, x(C)(-), and b(0,+), which are linked, via a disulfide bond, to the type II membrane glycoproteins, 4F2 heavy chain (4F2hc), or rBAT (related to b(0,+) amino acid transporter). Asc-1 required 4F2hc for its functional expression. In Western blot analysis in the nonreducing condition, a 118-kDa band, which seems to correspond to the heterodimeric complex of Asc-1 and 4F2hc, was detected in the mouse brain. The band shifted to 33 kDa in the reducing condition, confirming that Asc-1 and 4F2hc are linked via a disulfide bond. Asc-1-mediated transport was not dependent on the presence of Na(+) or Cl(-). Although Asc-1 showed a high sequence homology (66% identity at the amino acid level) to the Na(+)-independent broad scope neutral amino acid transporter LAT2 (Segawa, H., Fukasawa, Y., Miyamoto, K., Takeda, E., Endou, H., and Kanai, Y. (1999) J. Biol. Chem. 274, 19745-19751), Asc-1 also exhibited distinctive substrate selectivity and transport properties. Asc-1 preferred small neutral amino acids such as Gly, L-Ala, L-Ser, L-Thr, and L-Cys, and alpha-aminoisobutyric acid as substrates. Asc-1 also transported D-isomers of the small neutral amino acids, in particular D-Ser, a putative endogenous modulator of N-methyl-D-aspartate-type glutamate receptors, with high affinity. Asc-1 operated preferentially, although not exclusively, in an exchange mode. Asc-1 mRNA was detected in the brain, lung, small intestine, and placenta. The functional properties of Asc-1 seem to be consistent with those of a transporter subserving the Na(+)-independent small neutral amino acid transport system asc.
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Lee NG, Jung SB, Ahn BY, Kim YH, Kim JJ, Kim DK, Kim IS, Yoon SM, Nam SW, Kim HS, Park WJ. Immunization of burn-patients with a Pseudomonas aeruginosa outer membrane protein vaccine elicits antibodies with protective efficacy. Vaccine 2000; 18:1952-61. [PMID: 10699346 DOI: 10.1016/s0264-410x(99)00479-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The aim of this study was to determine whether the antibodies raised in burn patients by active immunization with a Pseudomonas aeruginosa OMPs vaccine have a protective efficacy against infection with P. aeruginosa. The binding patterns with P. aeruginosa OMPs of immunized burn patient sera were similar to the sera of immunized healthy humans as determined by immunoblot and immunoprecipitation analyses. The sera pooled from immunized burn patients after three immunizations showed a significantly higher opsonophagocytic-killing activity than the corresponding pre-immune sera, while the sera from unimmunized patients collected at the same day did not. Passive immunization of mice with post-immune sera of burn patients significantly enhanced the survival rate upon a lethal challenge with P. aeruginosa compared to the pre-immune sera, indicating the protective ability of the antibodies induced in burn patients by immunization. These results suggest that anti-P. aeruginosa OMPs antibodies elicited in burn patients by active immunization are protective against infection with P. aeruginosa, and provide a rational for further development of the vaccine for prevention against P. aeruginosa infection in burn patients.
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Kim DI, Lee SJ, Lee BB, Kim YI, Chung CS, Seo DW, Lee KH, Ko YH, Kim DK, Do YS, Byun HS. The relationship between the angiographic findings and the clinical features of carotid artery plaque. Surg Today 2000; 30:37-42. [PMID: 10648081 DOI: 10.1007/pl00010044] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The purpose of this study was to investigate the histological characteristics of atheromatous carotid plaque, and to analyze the relationship between the angiographic findings and the clinical features. We retrospectively reviewed 55 cases of carotid endarterectomy for extracranial internal carotid artery stenosis, who were treated at our institute from January 1995 to December 1997. The histological examination included hematoxylin-eosin staining, Masson-trichrome staining, and immunostaining for antismooth muscle antibody and anti-CD68 antibody. The main compositions of the carotid plaque included synthetic type vascular smooth muscle cells and extracellular matrix. The histological findings showed ulceration in 49 (89.1%) cases, calcium deposits in 42 (76.4%) cases, and an inflammatory reaction in 44 (80.0%) cases. Neurological abnormalities were strongly associated with plaque ulceration (P = 0.045) and an inflammatory reaction (P = 0.013), whereas no correlation existed regarding calcium deposits (P = 0.173). The angiographic findings showed ulceration in 46 (83.6%) cases. Plaque ulceration in the angiography findings showed no statistically significant correlation with the histologic findings (P = 0.410) and preoperative neurologic abnormalities (P = 0.059). All of the atherosclerotic risk factors such as hypertension, smoking, diabetes mellitus, hyperlipidemia, and myocardial infarction had no statistically significant correlation with the histological features of the carotid plaque. In conclusion, the main compositions of carotid plaque were synthetic-type vascular smooth muscle cells and extracellular matrix. The histological ulceration and inflammatory reaction of the plaque showed a statistically significant correlation with the preoperative neurologic symptoms, whereas no correlation was seen in the calcium deposits. Angiographic ulceration showed no correlation with the histological findings or preoperative neurologic abnormalities. In addition, the histological findings showed no correlation with the atherosclerotic risk factors.
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Cha SH, Sekine T, Kusuhara H, Yu E, Kim JY, Kim DK, Sugiyama Y, Kanai Y, Endou H. Molecular cloning and characterization of multispecific organic anion transporter 4 expressed in the placenta. J Biol Chem 2000; 275:4507-12. [PMID: 10660625 DOI: 10.1074/jbc.275.6.4507] [Citation(s) in RCA: 304] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A cDNA encoding a novel multispecific organic anion transporter, OAT4, was isolated from a human kidney cDNA library. The OAT4 cDNA consisted of 2210 base pairs that encoded a 550-amino acid residue protein with 12 putative membrane-spanning domains. The amino acid sequence of OAT4 showed 38 to 44% identity to those of other members of the OAT family. Northern blot analysis revealed that OAT4 mRNA is abundantly expressed in the placenta as well as in the kidney. When expressed in Xenopus oocytes, OAT4 mediated the high affinity transport of estrone sulfate (K(m) = 1.01 microM) and dehydroepiandrosterone sulfate (K(m) = 0.63 microM) in a sodium-independent manner. OAT4 also mediated the transport of ochratoxin A. OAT4-mediated transport of estrone sulfate was inhibited by several sulfate conjugates, such as p-nitrophenyl sulfate, alpha-naphthyl sulfate, beta-estradiol sulfate, and 4-methylumbelliferyl sulfate. By contrast, glucuronide conjugates showed little or no inhibitory effect on the OAT4-mediated transport of estrone sulfate. OAT4 interacted with chemically heterogeneous anionic compounds, such as nonsteroidal anti-inflammatory drugs, diuretics, sulfobromophthalein, penicillin G, and bile salts, whereas tetraethylammonium, an organic cation, did not. OAT4 is the first member of the multispecific organic anion transporter family, which is expressed abundantly in the placenta. OAT4 might be responsible for the elimination and detoxification of harmful anionic substances from the fetus.
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Jung YG, Peterson IM, Kim DK, Lawn BR. Lifetime-limiting strength degradation from contact fatigue in dental ceramics. J Dent Res 2000; 79:722-31. [PMID: 10728973 DOI: 10.1177/00220345000790020501] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The hypothesis under examination in this paper is that the lifetimes of dental restorations are limited by the accumulation of contact damage during oral function; and, moreover, that strengths of dental ceramics are significantly lower after multi-cycle loading than after single-cycle loading. Accordingly, indentation damage and associated strength degradation from multi-cycle contacts with spherical indenters in water are evaluated in four dental ceramics: "aesthetic" ceramics-porcelain and micaceous glass-ceramic (MGC), and "structural" ceramics-glass-infiltrated alumina and yttria-stabilized tetragonal zirconia polycrystal (Y-TZP). At large numbers of contact cycles, all materials show an abrupt transition in damage mode, consisting of strongly enhanced damage inside the contact area and attendant initiation of radial cracks outside. This transition in damage mode is not observed in comparative static loading tests, attesting to a strong mechanical component in the fatigue mechanism. Radial cracks, once formed, lead to rapid degradation in strength properties, signaling the end of the useful lifetime of the material. Strength degradation from multi-cycle contacts is examined in the test materials, after indentation at loads from 200 to 3000 N up to 10(6) cycles. Degradation occurs in the porcelain and MGC after approximately 10(4) cycles at loads as low as 200 N; comparable degradation in the alumina and Y-TZP requires loads higher than 500 N, well above the clinically significant range.
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Choi HK, Jung GW, Moon KH, Xin ZC, Choi YD, Lee WH, Rha KH, Choi YJ, Kim DK. Clinical study of SS-cream in patients with lifelong premature ejaculation. Urology 2000; 55:257-61. [PMID: 10688090 DOI: 10.1016/s0090-4295(99)00415-x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVES To investigate the clinical efficacy of SS-cream, the topical agent made from the extracts of nine natural products for the treatment of premature ejaculation, we performed a double-blind, randomized, placebo-controlled Phase III clinical study of patients with lifelong premature ejaculation in three medical centers. METHODS One hundred six patients (mean age 38.7 +/- 0.61 years) completed this study. The ejaculatory latency measured by stopwatch and sexual satisfaction ratio of both partner and patient were investigated twice in the screening period and once after each treatment (1 placebo 0.20 g and 5 SS-cream 0.20 g for a total of six treatments). Patients were instructed to apply the cream on the glans penis 1 hour before sexual intercourse in a double-blind randomized fashion. Clinical efficacy was compared with the prolongation of ejaculatory latency and improvement of the sexual satisfaction ratio before and after each treatment. RESULTS In the screening period, the mean ejaculatory latency was assessed at 1.37 +/- 0.12 minutes, and neither the patients nor their partners were satisfied with their sexual lives. After treatment, the mean ejaculatory latency was prolonged to 2.45 +/- 0.29 minutes in the placebo group and 10.92 +/- 0.95 minutes in the SS-cream group. The clinical efficacy of placebo and SS-cream as judged by an ejaculatory latency time prolonged more than 2 minutes was 15.09% and 79.81%, respectively. The improvement of sexual satisfaction to a grade higher than effective was 19.81% and 82.19%, respectively, for placebo and SS-cream. Of 530 trials of SS-cream, 98 (18.49%) resulted in a sense of mild local burning and mild pain. No adverse effect on sexual function or partner and no systemic side effects were observed. CONCLUSIONS According to these results, SS-cream is effective and safe in the treatment of premature ejaculation, with mild local side effects.
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Xin ZC, Choi YD, Lee WH, Choi YJ, Yang WJ, Choi HK, Kim DK. Penile vibratory threshold changes with various doses of SS-cream in patients with primary premature ejaculation. Yonsei Med J 2000; 41:29-33. [PMID: 10731916 DOI: 10.3349/ymj.2000.41.1.29] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
SS-cream made with extracts from natural products is a topical agent for treating premature ejaculation (PE). In order to elucidate the penile vibratory threshold changes and clinical effects of various doses of SS-cream, 53 patients with primary PE were investigated in a double-blind randomized placebo-controlled study. The mean age was 37.3 +/- 6.4 years and mean ejaculatory latency was 1.37 +/- 0.52 minutes. Neither the patients nor their sexual partners were satisfied with their sexual lives. Vibratory threshold at the glans penis, penile shaft, scrotum and index finger were measured using a biothesiometer twice during the screening period and three times one hour after the application of respective creams (SS-cream 0.05, 0.10. 0.15, 0.20 gm and placebo 0.10 gm) on the glans penis according to the order of the allocation table in a randomized fashion. The efficacy of SS-cream was defined as when the vibration threshold increased by more than 4 microns compared to the value tested during the screening period. The vibratory thresholds at the glans penis increased significantly in a dose-dependent manner after the application of various doses (0.05, 0.10, 0.15, 0.20 gm) of SS-cream (p < 0.001), and the efficacy of SS-cream on the penile vibration threshold increased according to the increased dosage (penile shaft: 48.4, 51.6, 54.8, 64.5%, glans penis: 58.1, 67.7, 77.4, 83.9%, respectively). With these results, we concluded that SS-cream increased the penile sensory threshold dose dependently, and therefore it is clinically effective for treating the heightened penile sensory response in patients with PE.
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Kim DK, Lim SW, Lee S, Sohn SE, Kim S, Hahn CG, Carroll BJ. Serotonin transporter gene polymorphism and antidepressant response. Neuroreport 2000; 11:215-9. [PMID: 10683861 DOI: 10.1097/00001756-200001170-00042] [Citation(s) in RCA: 268] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We examined allelic polymorphisms of the serotonin transporter (5-HTT) gene and antidepressant response to 6 weeks' treatment with the selective serotonin reuptake inhibitor (SSRI) drugs fluoxetine or paroxetine. We genotyped 120 patients and 252 normal controls, using polymerase chain reaction of genomic DNA with primers flanking the second intron and promoter regions of the 5-HTT gene. Diagnosis of depression was not associated with 5-HTT polymorphisms. Patients homozygous l/l in intron 2 or homozygous s/s in the promoter region showed better responses than all others (p < 0.0001, p = 0.0074, respectively). Lack of the l/l allele form in intron 2 most powerfully predicted non-response (83.3%). Response to SSRI drugs is related to allelic variation in the 5-HTT gene in depressed Korean patients.
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Kwon K, Chung N, Ha JW, Rim SJ, Kim HJ, Chang KJ, Lee BK, Pyun WB, Kim IJ, Kim DK, Choi DH, Jang YS, Lee JD, Cho SY, Kim SS. Assessments of myocardial perfusion in human using stress intravenous PESDA myocardial contrast echocardiography and Pulse Inversion Harmonic Imaging: A Comparison study with Tc-99m sestamibi SPECT. Korean Circ J 2000. [DOI: 10.4070/kcj.2000.30.7.793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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196
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Park JE, Lee WH, Hwang TH, Chu JA, Kim S, Choi YH, Kim JS, Kim DK, Lee SH, Hong KP, Seo JD, Lee WR. Aging affects the association between endothelial nitric oxide synthase gene polymorphism and acute myocardial infarction in the Korean male population. Korean J Intern Med 2000; 15:65-70. [PMID: 10714094 PMCID: PMC4531736 DOI: 10.3904/kjim.2000.15.1.65] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES The aging process affects responsiveness and other functions of endothelium and vascular smooth muscle cells, predisposing the old vessels to the development of atherosclerotic lesions. Endothelial nitric oxide synthase (ecNOS) gene polymorphisms were shown to affect the occurrence of acute myocardial infarction (AMI). We hypothesized that aging may affect the association between the ecNOS gene polymorphism and AMI. METHODS We investigated the age-related distribution of the ecNOS gene a/b polymorphism in 121 male AMI patients and 206 age-matched healthy male controls. RESULTS The aa, ab and bb genotypes were found in 1, 49 and 156 cases among the control subjects and 5, 23 and 93 cases among the AMI patients, respectively. There was a significant correlation between the ecNOS polymorphism and AMI (p = 0.045). When the correlation was analyzed by age, the significance remained only in the group below the age of 51 (p = 0.009). The proportion of smokers was increased in the young patients when compared to the old patients (p = 0.033), indicating that smoking also has greater effect on the younger population. The incidences of hypertension and diabetes mellitus, however, were similar in both populations. CONCLUSION Our work provides the first evidence that links ecNOS polymorphism to the risk of AMI in relation to age. Young persons who smoke or have ecNOSaa genotype may have an increased risk of developing AMI. The functional as well as structural changes associated with aging in the vascular endothelium may mask the effect of the ecNOS polymorphism in the development of AMI in old persons.
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197
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Chung TS, Kim DK, Yoon MS, Yang WI. Angiolymphoid hyperplasia with eosinophilia showing characteristics of Kimura's disease. J Dermatol 2000; 27:27-30. [PMID: 10692821 DOI: 10.1111/j.1346-8138.2000.tb02113.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Angiolymphoid hyperplasia with eosinophilia (ALHE) is a rare benign condition affecting principally the head and neck region of young females. We describe a 42-year-old female patient of ALHE showing the typical changes of endothelial cells and features similar to Kimura's disease in histologic and immunohistochemical findings.
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Byun J, Huh JE, Park SJ, Jang JE, Suh YL, Lee JS, Gwon HC, Lee WR, Cosset FL, Kim DK. Myocardial injury-induced fibroblast proliferation facilitates retroviral-mediated gene transfer to the rat heart in vivo. J Gene Med 2000; 2:2-10. [PMID: 10765500 DOI: 10.1002/(sici)1521-2254(200001/02)2:1<2::aid-jgm83>3.0.co;2-o] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Efficient and stable transfer of therapeutic DNA into injured myocardium would be an initial step towards a genetic treatment aimed at myocardial repair after myocardial infarction. Proliferating cardiac fibroblasts in the healing myocardium could be a compelling target for retroviral infection. We evaluated the feasibility of direct in vivo gene transfer into injured myocardium using a high-titer, stable retroviral vector. METHODS Using the TE-FLY-A-based MFG retroviral vector harboring nlsLacZ reporter, the gene transfer efficiency was assessed first in vitro in rat cardiac fibroblasts, followed by in vivo evaluation in healing rat myocardium after local freeze-thaw injury. A total of 2.5 x 10(7) infectious units of retrovirus were injected into the injured region of a beating rat heart. The transduced cells were identified by X-gal staining and immunohistochemistry. RESULTS Highly efficient transduction of cardiac fibroblasts was observed in vitro with 98% of the cells transduced with single infection. The cell proliferation index in the cardiac granulation tissue appeared maximal 3 days after cryoinjury. Retroviral injection into the injured beating heart induced gene expression localized to the wound repair region. One week after retrovirus injection, 14% of the cells in the reparative tissue were beta-gal-positive, while 4% were beta-gal-positive after 4 weeks. The transduced cells were mostly myofibroblasts. CONCLUSIONS Local gene transfer to the healing rat heart is feasible by retrovirus in vivo. This observation may serve as a useful guide for the development of gene therapy aimed at myocardial repair after myocardial infarction.
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Kim DK, Rajput V. Aortic-valve sclerosis. N Engl J Med 1999; 341:1856; author reply 1856-7. [PMID: 10610469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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Kim DK, Lee KT, Eun JS, Zee OP, Lim JP, Eum SS, Kim SH, Shin TY. Anti-allergic components from the peels of Citrus unshiu. Arch Pharm Res 1999; 22:642-5. [PMID: 10615874 DOI: 10.1007/bf02975340] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
In a bioassay-guided search for anti-allergic compounds from higher plants of Korea, polymethoxyflavones, 3',4',5,6,7,8-hexamethoxyflavone (1), 5-hydroxy-3',4',6,7,8-pentamethoxyflavone (II) and 3',4',5,7,8,-pentamethoxyflavone (III) have been isolated from the immature peels of Citrus unshiu. Structures of these compounds were elucidated on the basis of spectroscopic techniques. Compounds I and II inhibited dose-dependently histamine release from the rat peritoneal mast cells activated by compound 48/80 or anti-DNP IgE.
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