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Jackwood MW, Hilt DA, Callison SA, Lee CW, Plaza H, Wade E. Spike glycoprotein cleavage recognition site analysis of infectious bronchitis virus. Avian Dis 2001; 45:366-72. [PMID: 11417816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
The spike glycoprotein of infectious bronchitis virus (IBV), a coronavirus, is translated as a precursor protein (So), then cleaved into two subunits (S1 and S2) by host cell serine proteases. In this study, we compared the cleavage recognition site of 55 IBV isolates to determine if the cleavage recognition site sequence, which consists of five basic amino acid residues, correlates with host cell range, serotype, geographic origin, and pathogenicity as it does in orthomyxoviruses and paramyxoviruses. The most common cleavage recognition site observed (33 of 55 viruses) was Arg-Arg-Ser-Arg-Arg, representing at least 11 different serotypes. Thus, cleavage recognition site does not appear to correlate with serotype. We also determined that cleavage recognition site sequence does not correlate with pathogenicity because attenuated and pathogenic isolates (different passages of the same virus) contain identical cleavage recognition site sequences. In addition, nephropathogenic strains had the same cleavage recognition site sequence as many nonnephropathogenic isolates. Cleavage recognition site sequence does correlate with viruses in different geographic regions, which may be an important characteristic to examine in epidemiologic studies. An IBV monoclonal antibody neutralization-resistant mutant (NR 18) had an unusual substitution of Ile for Arg at the fourth position, giving the sequence Arg-Arg-Ser-Ile-Arg, which likely prevents cleavage and, thus, destroys the conformationally dependent monoclonal antibody binding epitope. Six residues on the amino-terminal side of the cleavage recognition site are conserved in 31% of the isolates and consist of only one or two basic amino acids. Thus, the number of basic residues around the cleavage recognition site does not appear to correlate with increased cleavability, host cell range, and increased virulence as it does with envelope glycoproteins in orthomyxoviruses and paramyxoviruses.
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Yamaoka T, Takahashi Y, Fujisato T, Lee CW, Tsuji T, Ohta T, Murakami A, Kimura Y. Novel adhesion prevention membrane based on a bioresorbable copoly(ester-ether) comprised of poly-L-lactide and Pluronic: in vitro and in vivo evaluations. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2001; 54:470-9. [PMID: 11426591 DOI: 10.1002/1097-4636(20010315)54:4<470::aid-jbm20>3.0.co;2-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Block copolymers consisting of poly(L-lactide) (PLLA) and poly(oxyethylene-co-oxypropylene), with various compositions, were synthesized and characterized in vitro and in vivo for their application as postoperative adhesion prevention membranes. It was found that the flexibility and degradability of the cast films of the block copolymers grew with increasing Pluronic F68 [PN; poly(oxyethylene-co-oxypropylene] composition. The receding contact angle of the copolymer films against water became lower than that of the PLLA film, because the surface was predominantly covered with more hydrophilic PN segments in a wet state. This surface property significantly affects the cell attachment property of the copolymer films, and the fibroblasts cultured on the films exhibit a spheroid-like morphology. The copolymer films subcutaneously implanted in the back of rats induced milder tissue responses compared with PLLA homopolymers, because of the increased surface hydrophilicity in the former. In vivo evaluation using a uterus horn model in rats revealed that the performance of these copolymer films as an adhesion-prevention membrane is comparable to that of a conventionally utilized membrane of oxidized regenerated cellulose. These results indicate that the copolymer films are biocompatible materials with controllable mechanical properties and biodegradability as adhesion-prevention membranes.
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Oh YB, Jun JB, Kim CK, Lee CW, Park CK, Kim TY, Yoo DH, Kim SY. Mixed connective tissue disease associated with skin defects of livedoid vasculitis. Clin Rheumatol 2001; 19:381-4. [PMID: 11055828 DOI: 10.1007/s100670070032] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A 21-year-old woman who had a 2-year history of mixed connective tissue disease (MCTD) developed rapidly evolving ulcers consistent with livedoid vasculitis (LV) in all distal extremities. She presented clinically with Raynaud's phenomenon, polyarthritis and swollen hands; serologically with high titres of ANA and anti-nRNP; and immunogenetically with HLA-DR4 and HLA-DR53. Although there was initial success in treatment except for the skin defects over the ankles, the patient died from disseminated intravascular coagulation. We suggest that LV may be a poor prognostic manifestation in MCTD.
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Bae DK, Park YK, Chi SG, Lee CW, Unni KK. Mutational alterations of the p16CDKN2A tumor suppressor gene have low incidence in mesenchymal chondrosarcoma. Oncol Res 2001; 12:5-10. [PMID: 11061340 DOI: 10.3727/000000001108747381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mutational inactivation of the cyclin-dependent kinase inhibitors (CDKIs) (p16INK4A/MTS1) tumor suppressor gene has been found in a variety of human tumor types. To investigate the involvement of CDKI abnormality in mesenchymal chondrosarcoma, alterations of CDKIs were examined in human mesenchymal chondrosarcoma tissues using a quantitative DNA/PCR, PCR-SSCP. Seven of 33 specimens (21.2%) showed abnormally low levels of p16CDKN2A amplification, suggesting that the allelic deletion of the gene might be a less frequent event in progression of this tumor. To detect subtle sequence alterations such as point mutations, SSCP analysis of the entire coding region of the p16CDKN2A gene, exons 1, 2, and 3 regions, showed no altered SSCP patterns in 33 mesenchymal chondrosarcoma specimens. A low incidence of genetic alterations of the p16CDKN2A was found in mesenchymal chondrosarcoma. Through this study, we conclude that alteration of the p16CDKN2A gene does not participate significantly in the tumorigenesis of mesenchymal chondrosarcoma.
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Lee CW, Mohr SN, Weisel CP. Toxicokinetics of human exposure to methyl tertiary-butyl ether (MTBE) following short-term controlled exposures. JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY 2001; 11:67-78. [PMID: 11409007 DOI: 10.1038/sj.jea.7500149] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Methyl tertiary-butyl ether (MTBE) is an oxygenated compound added to gasoline to improve air quality as part of the US Federal Clean Air Act. Due to the increasing and widespread use of MTBE and suspected health effects, a controlled, short-term MTBE inhalation exposure kinetics study was conducted using breath and blood analyses to evaluate the metabolic kinetics of MTBE and its metabolite, tertiary-butyl alcohol (TBA), in the human body. In order to simulate common exposure situations such as gasoline pumping, subjects were exposed to vapors from MTBE in gasoline rather than pure MTBE. Six subjects (three females, three males) were exposed to 1.7 ppm of MTBE generated by vaporizing 15 LV% MTBE gasoline mixture for 15 min. The mean percentage of MTBE absorbed was 65.8 +/- 5.6% following exposures to MTBE. The mean accumulated percentages expired through inhalation for 1 and 8 h after exposure for all subjects were 40.1% and 69.4%, respectively. The three elimination half-lives of the triphasic exponential breath decay curves for the first compartment was 1-4 min, for the second compartment 9-53 min, and for the third compartment 2-8 h. The half-lives data set for the breath second and blood first compartments suggested that the second breath compartment rather than the first breath compartment is associated with a blood compartment. Possible locations for the very short breath half-life observed are in the lungs or mucous membranes. The third compartment calculated for the blood data represent the vessel poor tissues or adipose tissues. A strong correlation between blood MTBE and breath MTBE was found with mean blood-to-breath ratio of 23.5. The peak blood TBA levels occurred after the MTBE peak concentration and reached the highest levels around 2-4 h after exposures. Following the exposures, immediate increases in MTBE urinary excretion rates were observed with lags in the TBA excretion rate. The TBA concentrations reached their highest levels around 6-8 h, and then gradually returned to background levels around 20 h after exposure. Approximately 0.7-1.5% of the inhaled MTBE dose was excreted as unchange urinary MTBE, and 1-3% was excreted as unconjugated urinary TBA within 24 h after exposure.
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Ryoo R, Park IS, Jun S, Lee CW, Kruk M, Jaroniec M. Synthesis of ordered and disordered silicas with uniform pores on the border between micropore and mesopore regions using short double-chain surfactants. J Am Chem Soc 2001; 123:1650-7. [PMID: 11456764 DOI: 10.1021/ja0038326] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Silica molecular sieves with uniform pores on the borderline between micropore (diameter <2 nm) and mesopore (from 2 to 50 nm) ranges were synthesized by a novel method using judiciously chosen mixtures of short double-chain alkylammonium surfactants. These silicas were characterized using X-ray diffraction (XRD), thermogravimetry, and nitrogen and argon adsorption. The calcined materials exhibited either 2-dimensional (2-D) hexagonal or disordered structures with XRD interplanar spacing from 2.51 to 2.93 nm, including the value of as small as 2.69 nm for highly ordered 2-D hexagonal silica. The dependence of the pore size and surfactant content on the surfactant chain length provided strong evidence for supramolecular templating being operative in the formation of small-pore silicas, even for the surfactant chain length of six carbon atoms. Both hexagonally ordered and disordered calcined samples were shown to exhibit narrow pore size distributions with maxima in the range from 1.96 to 2.61 nm (reliably evaluated on the basis of the unit-cell dimension and pore volume for 2-D hexagonal materials, and calculated using a properly calibrated procedure), tailored by the surfactant chain length. The samples exhibited primary pore volumes from 0.28 to 0.54 cm(3) g(-1) and specific surface areas from 730 to 930 m(2) g(-1). Because of their small yet uniform pore size and large specific surface area, the silicas reported herein promise to be useful in applications in adsorption and catalysis. Adsorption studies of these materials provided a unique new insight into the pore-filling mechanism for small-pore materials. Moreover, the approach proposed herein is expected to facilitate the synthesis of not only small-pore silicas but also materials with other framework compositions, thus largely contributing to bridging the gap in attainable pore sizes between micropore and mesopore ranges.
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Hong KH, Cho YH, Lee MH, Choi GS, Lee CW. Simultaneous measurement of 89Sr and 90Sr in aqueous samples by liquid scintillation counting using the spectrum unfolding method. Appl Radiat Isot 2001; 54:299-305. [PMID: 11200892 DOI: 10.1016/s0969-8043(00)00287-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two radiostrontium isotopes, 89Sr and 90Sr, were measured simultaneously by liquid scintillation counter coupling with a full spectrum DPM counting protocol. Strontium was separated from the aqueous media by extraction chromatography using Sr-spec resin. Individual count rates were evaluated from quench correlation curves for 89Sr and 90Sr related with SIS and tSIE quench indicators. The method exhibited a counting efficiency of 95% for 89Sr and 92% for 90Sr within their full energy channels and gave highly precise results when the sample was counted within 4 h after strontium separation. Lower limits of detection were 37 mBq/l for 90Sr and 32 mBq/l for 89Sr with a 60 min counting time.
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Son HS, Hong BH, Lee CW, Yun S, Kim KS. A new type of helix pattern in polyalanine peptide. J Am Chem Soc 2001; 123:514-5. [PMID: 11456562 DOI: 10.1021/ja0014640] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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184
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Lee CH, Choi YH, Yang SH, Lee CW, Ha SJ, Sung YC. Hepatitis C virus core protein inhibits interleukin 12 and nitric oxide production from activated macrophages. Virology 2001; 279:271-9. [PMID: 11145908 DOI: 10.1006/viro.2000.0694] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A characteristic feature of hepatitis C virus (HCV) infection is a high frequency of persistence and the progression to chronic liver diseases. Recent data suggest that prevalent T helper (Th) 2 immunity as well as weak HCV-specific T-cell response is associated with viral persistence. Here, we showed that the production of interleukin 12 (IL-12) and nitric oxide (NO) that is critical for the induction of Th1 and innate immunity, but not that of tumor necrosis factor alpha (TNF-alpha), was significantly suppressed in both HCV core-expressing macrophage cell lines and mouse peritoneal macrophages treated with recombinant core protein. In addition, IL-12 p40 promoter activity was repressed by the presence of HCV core in macrophages stimulated with lipopolysaccharride (LPS) following IFN-gamma treatment, indicating that IL-12 production may be downregulated at the transcriptional level. We also found that proliferation of T cells and IFN-gamma production in mixed lymphocyte reactions (MLR) with core-expressing cells were inhibited. Taken together, our results suggest that HCV core protein could play roles in suppressing the induction of Th1 immunity through inhibition of IL-12 and NO production.
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185
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Lee CW, Hilt DA, Jackwood MW. Identification and analysis of the Georgia 98 serotype, a new serotype of infectious bronchitis virus. Avian Dis 2001; 45:164-72. [PMID: 11332478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Twenty-five field infectious bronchitis viruses (IBVs) similar to, but genetically distinct from, the DE072 serotype were isolated from several states in the United States from 1990 through 1999 and were examined molecularly and antigenically. A 421-bp sequence in the hypervariable region of the S1 gene was examined, and phylogenetic analysis on that region indicated that these viruses are closely related but fall into unique groups. Cross-virus neutralization testing and entire S1 sequence analysis on selected isolates further confirmed that fact, and we divided the viruses into the DE072 serotype and two other unique groups. In a vaccine protection trial, the commercially available DE072 vaccine showed less than 50% protection against viruses in one of the groups. The majority of the recent isolates belong to that group and share very low antigenic relatedness to the DE072 strain as well as other serotypes of IBV. Consequently, we designated this group as a new serotype, Georgia 98. We developed a restriction fragment length polymorphism analysis that can differentiate this new serotype from all other serotypes of IBV.
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Abstract
The entire S2 gene of the DE072 strain of infectious bronchitis virus (IBV) was sequenced. The nucleotide and amino acid sequence was most similar to the D1466 strain and was 84.8% and 89.9% identity, respectively. The nucleotide and amino acid sequence similarity among the DE072 strain and other IBV strains was less than 71.9% and 76.6%, respectively. Phylogenetic analysis, based on both nucleotide and amino acid sequence, showed that IBV isolates were divided into two distinct groups. The DE072 strain clustered only with the D1466 strain, and all of the other strains were distinct from those two viruses. Further the nucleotide sequence analysis of the entire spike glycoprotein gene of the DE072 strain demonstrated that most of the gene contained a D1466-like sequence, and five putative cross-over sites were identified. Based on cross-over site, phylogenetic trees were constructed for different regions of the spike gene, and a difference in topology between these trees was observed. Considering the difference in S2 gene sequence identity and tree topology, we assume that DE072 and D1466 viruses share a different origin from other isolates of IBV. Furthermore, entire spike gene analysis indicates that the DE072 strain has undergone recombination event as well as extensive antigenic variation.
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187
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Lemieux PM, Lee CW, Ryan JV, Lutes CC. Bench-scale studies on the simultaneous formation of PCBs and PCDD/Fs from combustion systems. WASTE MANAGEMENT (NEW YORK, N.Y.) 2001; 21:419-425. [PMID: 11280982 DOI: 10.1016/s0956-053x(00)00133-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The presence of endocrine disrupting chemicals (EDCs) in the environment has wide-ranging potential ecological and health impacts on animals and humans. A significant amount of experimental and theoretical work has been performed the examining formation and control of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), which account for only part of the EDCs being emitted from combustion devices. Generally accepted mechanistic theories for PCDD/F formation propose heterogeneous reactions in the cooler regions of the combustor involving gas-phase organic precursors (such as chlorobenzenes or chlorophenols), a chlorine donor [such as hydrogen chloride (HCl)], and a flyash-bound metallic catalyst (such as copper chloride). There is evidence that some other proposed EDCs, including polychlorinated biphenyls (PCBs), are formed through a similar mechanistic pathway as PCDD/Fs. In addition, there is evidence that certain important steps in the catalytic reaction between the copper catalyst and the organic precursors may suggest a common rate limiting step for the heterogeneous formation of the previously mentioned EDCs. This paper reports on a bench-scale experimental study to characterize a newly built reactor system that was built to: produce levels and distributions of PCDD/F production similar to those achieved by previous researchers; verify similar responses to changes in independent variables; examine the hypothesis that PCB formation rates exhibit trends similar to PCDD/F formation rates as reactor variables are changed; and begin to explore the dependence of PCB formation on temperature and precursor type. The reactor system has been built, and initial reactor characterization studies have been performed. Initial experiments yielded results that support the hypothesis of a similar formation mechanism of PCBs and PCDD/Fs in combustors. Initial experiments uncovered potential deficiencies with the reactor system and the experimental procedures and have suggested corrective action to improve the experimental system.
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Cho GY, Lee CW, Hong MK, Kim JJ, Park SW, Park SJ. Effects of stent design on side branch occlusion after coronary stent placement. Catheter Cardiovasc Interv 2001; 52:18-23. [PMID: 11146516 DOI: 10.1002/1522-726x(200101)52:1<18::aid-ccd1006>3.0.co;2-#] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study was performed to assess the immediate and long-term patency of stent-associated side branches (SB) according to the types of stent. A total of 314 patients with 332 lesions (CrossFlex stent 86, NIR 100, GFX 146) had 365 SB (>1 mm) covered by coronary stents. Side branch occlusion (SBO) occurred in 7.7% of CrossFlex stent, in 10.5% of NIR stent and in 8.8% of GFX stent (P = NS). SBO primarily occurred in SB with ostial disease, and the presence of SB ostial disease was the only independent predictors of SBO after stenting (OR 22.1, 95% CI 9.47-51.49, P < 0.001). At 6 months follow-up, 11 of 31 SBO regained the patency, but the remaining SB had persistent SBO. Delayed SBO occurred in 8 SB, being associated with the presence of SB ostial disease and in-stent restenosis. In conclusions, SBO was not associated with the types of stent design, but with the SB lesion morphology.
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Lee MH, Choi GS, Cho YH, Lee CW, Shin HS. Concentrations and activity ratios of uranium isotopes in the groundwater of the Okchun Belt in Korea. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2001; 57:105-116. [PMID: 11545379 DOI: 10.1016/s0265-931x(01)00014-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Groundwater samples obtained from the Okchun Belt in Korea were separated into particulate and filtered fraction using a 0.45 microm membrane filter and concentrations and activity ratios of uranium isotopes in the fractions were determined by chemical separation and alpha-spectrometric measurements. Most of the uranium isotopes in the groundwater were found in the filtered water. Only less than 1% of the total uranium was detected in the particulate fraction. The concentrations and activity ratios of uranium isotopes in the groundwater measured in this study were variable, depending upon sampling site. Owing to a rapid material exchange between the subterranean hot waters and the rock strata, the concentrations of 238U in the groundwater in the hot spring area were found to be about four times higher than those elsewhere. Because of the alpha-particle recoil effect, the activity ratios of 234U/238U in the groundwater taken at "cold" spring sites were variable within the range 1.20 to 3.58, depending on the residence time of the groundwater. In the hot spring area, the activity ratios of 234U/238U were close to the equilibrium value (1.10 +/- 0.07) due to rapid erosion of the rock strata by the hot spring water.
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190
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Lee CW, Hong MK, Kim HS, Rhee KS, Kim JJ, Park SW, Park SJ. Determinants of coronary blood flow following primary angioplasty for acute myocardial infarction. Catheter Cardiovasc Interv 2000; 51:402-6. [PMID: 11108669 DOI: 10.1002/1522-726x(200012)51:4<402::aid-ccd6>3.0.co;2-m] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The aim of this study was to evaluate determinants of coronary blood flow following primary angioplasty (PA) in acute myocardial infarction (AMI). The corrected TIMI (thrombolysis in myocardial infarction) frame count and the TIMI flow grade were used as indexes of coronary blood flow, and its determinants were examined in 115 consecutive AMI patients who underwent PA (pain onset </= 12 hr). The following were validated as univariate predictors of slower corrected TIMI frame count: a lower pressure-derived farctional collateral flow (PDCF) index (P < 0.01), poor angiographic collaterals (P < 0.01), TIMI flow 0, 1 before PA (P < 0.05), and the presence of heavy thrombi (P < 0.01). The PDCF index and the presence of heavy thrombi were independent predictors of the corrected TIMI frame count. Likewise, the PDCF index (chi(2) = 12.9; P < 0.01) and the presence of heavy thombi (chi(2) = 11.4; P < 0.01) were independent predictors of TIMI 3 flow. In conclusion, collateral flow and the presence of thrombi are major determinants of coronary blood flow after PA in AMI.
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191
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Lemieux PM, Lee CW, Ryan JV. Prediction of dioxin/furan incinerator emissions using low-molecular-weight volatile products of incomplete combustion. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2000; 50:2129-2137. [PMID: 11140141 DOI: 10.1080/10473289.2000.10464240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from incinerators and other stationary combustion sources are of environmental concern because of the toxicity of certain PCDD/F congeners. Measurement of trace levels of PCDDs/Fs in combustor emissions is not a trivial matter. Development of one or more simple, easy-to-measure, reliable indicators of stack PCDD/F concentrations not only would enable incinerator operators to economically optimize system performance with respect to PCDD/F emissions, but could also provide a potential technique for demonstrating compliance status on a more frequent basis. This paper focuses on one approach to empirically estimate PCDD/F emissions using easy-to-measure volatile organic C2 chlorinated alkene precursors coupled with flue gas cleaning parameters. Three data sets from pilot-scale incineration experiments were examined for correlations between C2 chlorinated alkenes and PCDDs/Fs. Each data set contained one or more C2 chloroalkenes that were able to account for a statistically significant fraction of the variance in PCDD/F emissions. Variations in the vinyl chloride concentrations were able to account for the variations in the PCDD/F concentrations strongly in two of the three data sets and weakly in one of the data sets.
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192
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Lee CW, Tomlinson B, Yeung JH, Lin G, Damani LA. Distribution of the N-oxidation of dietary-derived trimethylamine in a male Chinese population. PHARMACOGENETICS 2000; 10:829-31. [PMID: 11191887 DOI: 10.1097/00008571-200012000-00008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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193
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Shikama N, Chan HM, Krstic-Demonacos M, Smith L, Lee CW, Cairns W, La Thangue NB. Functional interaction between nucleosome assembly proteins and p300/CREB-binding protein family coactivators. Mol Cell Biol 2000; 20:8933-43. [PMID: 11073993 PMCID: PMC86548 DOI: 10.1128/mcb.20.23.8933-8943.2000] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2000] [Accepted: 09/05/2000] [Indexed: 12/24/2022] Open
Abstract
The p300/CREB-binding protein (CBP) family of proteins consists of coactivators that influence the activity of a wide variety of transcription factors. Although the mechanisms that allow p300/CBP proteins to achieve transcriptional control are not clear, it is believed that the regulation of chromatin is an important aspect of the process. Here, we describe a new level of p300-dependent control mediated through the functional interaction between p300/CBP and members of the family of nucleosome assembly proteins (NAP), which includes NAP1, NAP2, and TAF1. We find that NAP proteins, which have previously been implicated in the regulation of transcription factor binding to chromatin, augment the activity of different p300 targets, including p53 and E2F, through a process that is likely to involve the physical interaction between p300 and NAP. NAP proteins can form oligomers, and the results show that NAP proteins can bind to both core histones and p300 coactivator proteins, perhaps in a multicomponent ternary complex. We also provide data in support of the idea that histones can influence the interaction between p300 and NAP protein. These results argue that NAP is a functionally important component of the p300 coactivator complex and suggest that NAP may serve as a point of integration between transcriptional coactivators and chromatin.
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Park SW, Lee CW, Hong MK, Kim JJ, Cho GY, Nah DY, Park SJ. Randomized comparison of coronary stenting with optimal balloon angioplasty for treatment of lesions in small coronary arteries. Eur Heart J 2000; 21:1785-9. [PMID: 11052843 DOI: 10.1053/euhj.1999.1947] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIMS Angioplasty of lesions in small coronary arteries remains a significant problem because of the increased risk of restenosis. The aim of this study was to compare the efficacy of elective coronary stent placement and optimal balloon angioplasty in small vessel disease. METHODS One hundred and twenty patients with lesions in small coronary arteries (de novo, non-ostial lesion and reference diameter <3 mm) were randomly assigned to either balloon angioplasty or elective stent placement (7-cell NIR stent). The primary end-point was restenosis at 6 months follow-up. Optimal balloon angioplasty was defined as diameter stenosis less than or = 30% and the absence of major dissection after the angioplasty, and crossover to stenting was allowed. RESULTS Baseline clinical and angiographic characteristics were similar in the two groups. Procedure was successful in all patients, and in-hospital events did not occur in any patient. However, 12 patients in the angioplasty group were stented because of suboptimal results or major dissection. Postprocedural lumen diameter was significantly larger in the stent group than in the angioplasty group (2.44 +/- 0.36 mm vs 2.14 +/- 0.36, P<0.05, respectively), but late loss was greater in the stent group (1.12 +/- 0.67 mm vs 0.63 +/- 0.48, P<0.01, respectively). The angiographic restenosis rate was 30.9% in the angioplasty group, and 35.7% in the stent group (P = ns). Clinical follow-up was available in all patients (15.9 +/- 5.7 months) and clinical events during the follow-up were similar in both groups. CONCLUSIONS These results suggest that optimal balloon angioplasty with provisional stenting may be a reasonable approach for treatment of lesions in small coronary arteries.
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Lee CW. Prevalences of subacute cutaneous lupus erythematosus and Epidermolysis bullosa acquisita among Korean/Oriental populations. Dermatology 2000; 197:187. [PMID: 9732174 DOI: 10.1159/000017997] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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196
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Hong MK, Park SW, Lee NH, Nah DY, Lee CW, Kang DH, Song JK, Kim JJ, Park SJ. Long-term outcomes of minor dissection at the edge of stents detected with intravascular ultrasound. Am J Cardiol 2000; 86:791-5, A9. [PMID: 11018205 DOI: 10.1016/s0002-9149(00)01085-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We evaluated the influences of minor edge dissections on late angiographic in-stent restenosis in 327 patients with 348 lesions (281 lesions without edge dissection and 67 lesions [19.3%] with edge dissection); the angiographic restenosis rate was 29.9% in the lesions with edge dissections versus 25.3% without edge dissections (p = 0.540). The minor non-flow-limiting dissections at the edge of stents may not be associated with the development of late angiographic in-stent restenosis.
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Lee CW. An extract of cultured A431 cells contains major tissue antigens of autoimmune bullous diseases. Br J Dermatol 2000; 143:821-3. [PMID: 11069463 DOI: 10.1046/j.1365-2133.2000.03838.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Autoantibodies that are characteristic of autoimmune bullous diseases (AIBDs) can be detected by immunoblot assay using epidermal or dermal extracts. However, none of the substrates obtained by ordinary methods seems to contain a sufficient amount of all of the autoantigens involved in AIBDs, and diagnosis may require the use of several different substrates. OBJECTIVES To examine the potential of A431 cell extracts as a substrate for immunoblotting. METHODS Fourteen sera obtained from patients with major AIBDs (pemphigus vulgaris, pemphigus foliaceus, paraneoplastic pemphigus, bullous pemphigoid and epidermolysis bullosa acquisita) were tested using this substrate. RESULTS Bands corresponding to desmoglein 1 and 3, desmoplakin 1 and 2, periplakin, BPAG1, BPAG2 and type VII collagen were identified distinctly with these sera. CONCLUSIONS This finding suggests that culture extracts of A431 cells provide an effective substrate for the diagnosis and differential diagnosis of major AIBDs.
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Liao WB, Lee CW, Tsai YS, Liu BM, Chung KJ. Influential factors affecting prognosis of snakebite patients management: Kaohsiung Chang Gung Memorial Hospital experience. CHANG GUNG MEDICAL JOURNAL 2000; 23:577-83. [PMID: 11126148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND The objective of this study was to determine the most influential factors affecting the prognosis of snakebite patients in Kaohsiung Chang Gung Memorial Hospital. METHODS A thorough review of the medical records of poisonous snakebite from June 1986 to November 1999 was carried out in this retrospective study. RESULTS Of the identified snakes in 39 bite victims, 70% of these cases were hemorrhagic type: Trimeresurus stejnegeri 20/27, T. mucrosquamatus 6/27, and Agkistrodon acutus 1/27; 28% were neurotoxic type: Naja naja atra 6/11 and Bungarus multicinctus 5/11; and 2% was mixed type: Vipera russelli formosensis 1/39. Three of four acute renal failure victims were bitten by T. mucrosquamatus. Two of the 5 victims bitten by B. multicinctus required endotracheal intubation to maintain their respiration. Five patients received skin grafting, 3 of whom were bitten by Naja naja atra. Most of our patients (55%) received only a single dose of antivenin, and 83% (29/35) of the antivenin was given within 6 hours after the bite; the antivenin infusion was finished in less than 2 hours in most cases (33/36). CONCLUSION Bites from Trimeresurus stejnegeri are the most common poisonous snakebite recorded in our emergency department. T. mucrosquamatus is prominent in causing bleeding tendency and acute renal failure. Bungarus multicinctus is more prominent than Naja naja atra in causing acute respiratory failure. The dosage of antivenin used to treat patient bitten by cobra was less than that recommended by the poison control center, and the complication of skin necrosis requiring skin grafting was more severe than that of the other species.
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Park SW, Lee CW, Kim HS, Lee NH, Nah DY, Hong MK, Kim JJ, Park SJ. Effects of cilostazol on angiographic restenosis after coronary stent placement. Am J Cardiol 2000; 86:499-503. [PMID: 11009265 DOI: 10.1016/s0002-9149(00)01001-8] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
This study evaluates the impact of cilostazol on post-stenting restenosis. Cilostazol is a potent antiplatelet agent with antiproliferative properties. Few data are available about the effect of cilostazol on poststenting restenosis. Four hundred nine patients (494 lesions) who were scheduled for elective stenting were randomized to receive aspirin plus ticlopidine (group I, n = 201, 240 lesions) or aspirin plus cilostazol (group II, n = 208, 254 lesions), starting 2 days before stenting. Ticlopidine was given for 1 month and cilostazol for 6 months. Follow-up angiography was performed at 6 months, and clinical evaluation at regular intervals. Baseline characteristics were similar between the 2 groups. The procedural success rate was 99.6% in group I and 100% in group II. There were no cases of stent thrombosis after stenting. Angiographic follow-up was performed in 380 of the 494 eligible lesions and the angiographic restenosis rate was 27% in group I and 22.9% in group II (p = NS). However, diffuse type in-stent restenosis was more common in group I than in group II (54.2% vs 26.8%, respectively, p <0.05). In diabetic patients, the angiographic restenosis rate was 50% in group I and 21.7% in group II (p <0.05). Clinical events during follow-up did not differ between the 2 groups. In conclusion, aspirin plus cilostazol seems to be an effective antithrombotic regimen with comparable results to aspirin plus ticlopidine, but it does not reduce the overall angiographic restenosis rate after elective coronary stenting.
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Hong MK, Park SW, Lee CW, Kang DH, Song JK, Kim JJ, Park SJ. Long-term outcomes of minor plaque prolapsed within stents documented with intravascular ultrasound. Catheter Cardiovasc Interv 2000; 51:22-6. [PMID: 10973013 DOI: 10.1002/1522-726x(200009)51:1<22::aid-ccd6>3.0.co;2-i] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The direct relationship between minor plaque prolapsed within stents and late in-stent restenosis is unknown. Therefore, we evaluated the impact of minor plaque prolapse on late angiographic in-stent restenosis. Intravascular ultrasonography (IVUS)-guided single-coronary stenting was successfully performed on 384 consecutive patients with 407 native coronary lesions. Six-month follow-up angiographic evaluation was performed on 315 patients (82. 0%) with 334 lesions (82.1%). Minor plaque prolapsed within the stent was found in 75 of 334 lesions (22.5%). Results were evaluated using angiographic and IVUS methods. The development of minor plaque prolapse was significantly associated with infarct-related artery (P = 0.000) and small pre-intervention minimal lumen diameter (P = 0. 001). The overall angiographic restenosis rate was 23.1% (77/334)-21.3% (16/75) in the lesions with plaque prolapse vs. 23.6% (61/259) in the lesions without plaque prolapse (P = 0.806). In conclusion, minor plaque prolapsed within stents might not be associated with late angiographic in-stent restenosis.
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