376
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Lee YC, Kawasaki N, Lee RT, Suzuki N. Quantum-dye labeled proteins for glycobiology: a viable nonradioactive alternative tracer. Glycobiology 1998; 8:849-56. [PMID: 9675217 DOI: 10.1093/glycob/8.9.849] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Quantum dye (QD), a macrocyclic europium-chelate, developed as a cytological marker, has never been used for quantitative applications. It would be ideal, however, if the same tracer can be used for both qualitative and quantitative purposes. We have labeled some lectins and neoglycoproteins with QD for the purpose of quantitative analyses in glycobiology, and tested its suitability in three different areas in glycobiology: (1) glycosyltransferase, (2) an animal lectin - mannose-binding protein, and (3) the Gal/GalNAc receptor of rat liver membrane. Usefulness of QD-labeled lectins was amply demonstrated by the quantification of galactosyltransferase activity using QD-soybean agglutinin and QD-RCA120 ( Ricinus communis agglutinin). We also showed that QD-labeled neoglycoproteins, QD-Man-BSA and QD-Gal-BSA, can replace radioiodinated counterparts in the binding assays of animal lectins (serum mannose binding protein and hepatic Gal/GalNAc receptor.) The advantage of QD and other europium labels is that it does not decay as radioiodides do. The long shelf-life results in more consistent results from repeated experiments.
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377
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Lim SJ, Shim HJ, Kwak BG, Kim HJ, Park HJ, Sa EJ, Min CH, Lee YC, Kim KS. Recanalization of obstructed Tenckhoff peritoneal dialysis catheter: wire/stylet manipulation combined with endoluminal electrocauterization. Cardiovasc Intervent Radiol 1998; 21:435-8. [PMID: 9853155 DOI: 10.1007/s002709900296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We report the results of fluoroscopically guided wire/stylet manipulation combined with endoluminal electrocauterization in seven patients with obstructed Tenckhoff peritoneal dialysis catheters. In preparation for clinical application, electrocauterization was performed using a stone basket to recanalize surgically removed Tenckhoff catheters obstructed with omental fat ingrowing through the side holes. All ingrowing omental fat was removed easily by electrocauterization with the rotating movement of a stone basket. The technique was then applied in vivo in seven cases with ingrowing omental fat and malpositioned catheter; six (86%) were successfully recanalized. Among those six cases with initial success, four maintained good catheter function with durable patency (mean 261.3 days). No significant complication was noted.
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378
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Lee KB, Wu P, Brand L, Lee YC. Conformational analysis of biantennary glycopeptides with a resonance energy transfer technique. Methods Mol Biol 1998; 76:237-55. [PMID: 9664357 DOI: 10.1385/0-89603-355-4:237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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379
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Deras IL, Takegawa K, Kondo A, Kato I, Lee YC. Synthesis of a high-mannose-type glycopeptide analog containing a glucose-asparagine linkage. Bioorg Med Chem Lett 1998; 8:1763-6. [PMID: 9873430 DOI: 10.1016/s0960-894x(98)00306-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The title compound was prepared by enzymatic transfer of oligosaccharide to a synthetic pentapeptide containing the Glc-Asn linkage. The compound was not hydrolyzed by glycoamidases from plant and bacterial sources, but it inhibited both enzymes in the micromolar range. Its activity is compared to other potential inhibitors.
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380
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Kim GE, Lim JJ, Park W, Park HC, Chung EJ, Seong J, Suh CO, Lee YC, Park HJ. Sensory and motor dysfunction assessed by anorectal manometry in uterine cervical carcinoma patients with radiation-induced late rectal complication. Int J Radiat Oncol Biol Phys 1998; 41:835-41. [PMID: 9652846 DOI: 10.1016/s0360-3016(98)00094-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE To investigate the effects of radiation on anorectal function in patients with carcinoma of the uterine cervix. METHODS AND MATERIALS Anorectal manometry was carried out on 24 patients (complication group) with late radiation proctitis. All of the manometric data from these patients were compared with those from 24 age-matched female volunteers (control group), in whom radiation treatment had not yet been performed. RESULTS Regardless of the severity of proctitis symptoms, 25% of patients demonstrated all their manometric data within the normal range, but 75% of patients exhibited one or more abnormal manometric parameters for sensory or motor functions. Six patients (25%) had an isolated sensory dysfunction, eight patients (33.3%) had an isolated motor dysfunction, and four patients (16.7%) had combined disturbances of both sensory and motor functions. The maximum tolerable volume, the minimal threshold volume, and the urgent volume in the complication group were significantly reduced compared with those in the control group. The mean squeeze pressure in the complication group was significantly reduced, whereas the mean resting pressure and anal sphincter length were unchanged. CONCLUSIONS Physiologic changes of the anorectum in patients with late radiation proctitis seem to be caused by a variety of sensory and/or motor dysfunctions in which many different mechanisms are working together. The reduced rectal reservoir capacity and impaired sensory functions were crucial factors for functional disorder in such patients. In addition, radiation damage to the external anal sphincter muscle was considered to be an important cause of motor dysfunction.
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381
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Lee RT, Gabius HJ, Lee YC. Thermodynamic parameters of the interaction of Urtica dioica agglutinin with N-acetylglucosamine and its oligomers. Glycoconj J 1998; 15:649-55. [PMID: 9881770 DOI: 10.1023/a:1006976129458] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The interaction between Urtica dioica agglutinin (UDA) and N-acetylglucosamine (GlcNAc) and its beta(1-4)-linked oligomers was studied by fluorescence titration and isothermal titration microcalorimetry. UDA possesses one significant binding site that can be measured calorimetrically. This site is composed of three subsites, each subsite accommodating one GlcNAc residue. The interaction is enthalpically driven, and the binding area of UDA is characterized by a deltaH of interaction for a given oligosaccharide considerably smaller than that of wheat germ agglutinin (WGA), despite the fact that they both belong to a family of proteins composed entirely of hevein domains. Relatively high deltaCp values of the UDA-carbohydrate interactions and more favorable entropy term compared to WGA suggest that binding of the carbohydrate ligands by UDA has a higher hydrophobic component than that of WGA.
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382
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Lee YC, Chen YS. Brief report: the temperamental characteristics of the Chinese adolescents in Taiwan. J Adolesc 1998; 21:337-40. [PMID: 9657899 DOI: 10.1006/jado.1998.0157] [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: 11/22/2022]
Abstract
A Chinese Adolescent Temperament Self rating questionnaire was completed by 1165 Chinese adolescents from high schools in or near Taipei City, Taiwan. Statistical analysis revealed the following results: (a) boys tended to show higher activity level, higher task orientation, higher intensity of reaction, higher tactile threshold and lower adaptability than girls; (b) junior graders tended to have lower rhythmicity, less initial approaching reaction toward new stimuli and lower adaptability than senior graders; (c) the eldest child tended to have higher adaptability, higher task orientation and higher rhythmicity than younger siblings in the family; and (d) those with a better educated father tended to have more positive mood, higher task orientation, higher adaptability, higher rhythmicity and more initial approaching reaction.
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383
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Thompson T, Lee YC. Pathological fracture in an 87-year-old woman. THE NEW ZEALAND MEDICAL JOURNAL 1998; 111:192-3. [PMID: 9640321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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384
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Saito K, Lee RT, Lee YC. Quantification of Eu3+ in quantum-dye-labeled materials by ashing and dissociation enhancement. Anal Biochem 1998; 258:311-4. [PMID: 9570846 DOI: 10.1006/abio.1998.2612] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Quantum Dye (QD) is an extremely stable macrocyclic chelate of Eu3+, measurable with a time-resolved fluorometer even without the aid of enhancement solution, albeit at a low sensitivity. However, QD is not easily quantified by the popular dissociation-enhancement methodology (I. Hemmilä et al., 1984, Anal. Biochem. 137, 335-343), because of difficulty in dissociating Eu3+ completely from QD. We found that Eu3+ in QD can be accurately measured by simple ashing followed by the dissociation-enhancement methodology. Validity of the method was tested by determining Eu(NO3)3 with or without ashing and analyzing Eu3+ in other chelates known to be amenable to accurate measurement by the dissociation enhancement.
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385
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Fujikawa K, Tsukamoto Y, Oki T, Lee YC. Spectroscopic studies on the interaction of pradimicin BMY-28864 with mannose derivatives. Glycobiology 1998; 8:407-14. [PMID: 9499388 DOI: 10.1093/glycob/8.4.407] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pradimicin BMY-28864 (Pm) is an antibiotic effective against yeasts and fungi, and is known to bind mannose in the presence of Ca2+. We examined spectroscopically the mode of interactions among Pm, Ca2+, and glycosides of mannose and mannose oligosaccharides (Manalpha1-OMe, Manalpha1-2Manalpha1-OMe, Manalpha1-3Manalpha1-OMe, Manalpha1-4Manalpha1-OMe, Manalpha1-6Manalpha1-OMe, Manalpha1-6(Manalpha1-3)Manalpha1-OMe, and Man9GlcNAc2-Asn, a high mannose type N-linked oligosaccharide). All the mannosides interacted with Pm in the presence of Ca2+ and caused absorbance changes. The absorbance changes occurred nonlinearly with respect to the carbohydrate concentration and do not follow a simple binding isotherm equation, suggesting a unique multistep interaction mode. The concentrations that induced half the maximum absorbance change were approximately 10 mM for the mono- and di-mannosides and around 1.5 mM for the trimannoside and Man9GlcNAc2-Asn. Methyl alpha-D-glucopyranoside, methyl alpha-D-galactopyranoside, lactose, and myo-inositol did not affect the absorbance of Pm up to 50 mM. Ca2+ alone also influenced the absorbance of Pm. The absorbance between 200 and 700 nm decreased hypochromically when Ca2+ was added. The concentration that gave half the maximum absorbance decrease caused by Ca2+was around 15 microM. Our results suggest that two Pm molecules bind one C a2+, and each Pm binds two mannosyl residues.
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386
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Takegawa K, Fujita K, Fan JQ, Tabuchi M, Tanaka N, Kondo A, Iwamoto H, Kato I, Lee YC, Iwahara S. Enzymatic synthesis of a neoglycoconjugate by transglycosylation with Arthrobacter endo-beta-N-acetylglucosaminidase: a substrate for colorimetric detection of endo-beta-N-acetylglucosaminidase activity. Anal Biochem 1998; 257:218-23. [PMID: 9514782 DOI: 10.1006/abio.1997.2543] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The transglycosylation activity of endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae was used for the enzymatic synthesis of a novel oligosaccharide, Man6GlcNAc-p-nitrophenyl-alpha-D-glucose (Man6GlcNAc-Glc-pNP). The reaction was efficiently induced in aqueous solution containing dimethyl sulfoxide. In the medium containing 20% (v/v) dimethyl sulfoxide with 0.1 M Glc-pNP as an acceptor, the transglycosylation attained yields of 75% by high-performance anion-exchange chromatography. The structure of Man6GlcNAc-Glc-pNP was confirmed by ion mass spectrometry and 400 MHz 1H NMR spectrometry. Various endo-beta-N-acetylglucosaminidases hydrolyzed this oligosaccharide and Man6GlcNAc and Glc-pNP were released from the oligosaccharide by endo-beta-N-acetylglucosaminidase digestion. We have established a new procedure for the colorimetric detection of endo-beta-N-acetylglucosaminidase activity using Man6Glc-NAc-Glc-pNP, which is simple as that for other exoglycosidase assays with pNP-glycosides as substrates.
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387
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Chan CY, Chen YS, Ko WJ, Wang SS, Chiu IS, Lee YC, Chu SH. Extracorporeal membrane oxygenation support for single lung transplantation in a patient with primary pulmonary hypertension. J Heart Lung Transplant 1998; 17:325-7. [PMID: 9563612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Left single lung transplantation was performed under perioperative extracorporeal membrane oxygenation (ECMO) support for a patient of primary pulmonary hypertension. Continuous ECMO in this patient for one day after the transplantation decreased the pulmonary blood flow and probably served to minimize the potential complication of reperfusion edema of the graft. During this period, the ECMO was gradually weaned so that the grafted lung could adapt itself to the gradually increased blood flow through it. The patient was extubated without difficulty 2 days alter the removal of ECMO and made a smooth recovery.
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388
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Kuo SH, Chang DB, Lee YC, Lee YT, Luh KT. Tumour-infiltrating lymphocytes in non-small cell lung cancer are activated T lymphocytes. Respirology 1998; 3:55-9. [PMID: 9657662 DOI: 10.1046/j.1440-1843.1998.d01-9.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
This study was carried out in order to investigate the local immune reaction of tumour-infiltrating lymphocytes (TILs) in the primary tumours of non-small cell lung carcinomas. Thirty non-small cell lung cancer (NSCLC) patients were included. The tumour tissue was taken at thoracotomy and monocellular suspension of the tumour was obtained by mechanical disaggregation. Dual-coloured flow cytometric analysis of TILs and their corresponding peripheral blood lymphocytes (PBLs) was performed. Tumour-infiltrating lymphocytes contained significantly higher proportions of CD3(+) T lymphocytes and CD8(+) T lymphocytes than the corresponding PBLs (82.0%+/-13.9% vs 66.3%+/-10.6% for CD3, P<0.001; 39.0%+/-18.4% vs 26.4%+/-5.2% for CD8, P<0.001). Tumour-infiltrating lymphocytes contained significantly higher proportions of activated memory lymphocytes than PBLs did (9.8%+/-8.6% vs 1.3%+/-1.5% for CD25, P<0.001; 40.5%+/-30.2% vs 10.2%+/-14.8% for CD71, P<0.001; 75.5%+/-11.9% vs 28.6%+/-9.8% for HLA-DR, P<0.001). These findings were also found in both CD4(+) TILs and CD8(+) TILs. The TILs of NSCLC contained higher proportions of T lymphocytes and CD8(+) lymphocytes than their corresponding peripheral bloods. The proportions of activated memory lymphocytes were also significantly higher in the TILs, both in CD4(+) TILs and CD8(+) TILs, than the corresponding PBLs.
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389
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Lee YC, Woodfield DG, Douglas R. Clinical usage of intravenous immunoglobulins in Auckland. THE NEW ZEALAND MEDICAL JOURNAL 1998; 111:48-50. [PMID: 9539915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
AIMS To review the indications for prescription of intravenous immunoglobulin (IVIg), in Auckland and the associated adverse effects. METHODS All patients who received IVIg infusions in four major hospitals in Auckland in 1996 were identified from blood bank records. Clinical details were recorded from case notes. RESULTS One hundred and thirty-five cases were identified and 131 records were available for review. Hypogammaglobulinaemia (n = 38) and thrombocytopenia (n = 38) were the two most common indications for 44% of Primary hypogammaglobulinaemia accounted for IVIg. the IVIg prescribed. IVIg was only used in one patient with hypogammaglobulinaemia secondary to chronic lymphocytic leukaemia and in one case of graft-versus-host disease. Adverse reactions were noted in 13 cases (10%). Headache (n = 4) and fever (n = 4) were the most commonly recorded side-effects. One patient developed acute renal failure after IVIg infusion. Written consent was documented in 7 patients (5%). CONCLUSIONS The indications for IVIg prescription were generally consistent with the recommendations of the Australasian Society of Blood Transfusion. Use of IVIg in haematological conditions other than immune thrombocytopaenic purpura was infrequent. Most of the IVIg infusions were administered uneventfully but some minor side effects were recorded and one significant clinical event may have been causally related to IVIg infusion.
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390
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Deras IL, Kawasaki N, Lee YC. Quantitative recovery of Man9GlcNAc2Asn derivatives from concanavalin A. Carbohydr Res 1998; 306:469-71. [PMID: 9679271 DOI: 10.1016/s0008-6215(97)10112-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Some larger high-mannose-type oligosaccharides bind very tightly to concanavalin A and are difficult to elute. We present conditions that permit the complete elution of compounds containing high-mannose type oligosaccharides from a popular concanavalin A-Sepharose that is commercially available. Europium-labeled Man9GlcNAc2Asn (N. Kawasaki and Y.C. Lee, Anal. Biochem., 250 (1997) 260-262), soybean agglutinin, and Eu(III)-labeled soybean agglutinin bound to concanavalin A-Sepharose were completely eluted with 1 M methyl alpha-D-mannopyranoside by allowing the column to stand in elution buffer, permitting the oligosaccharide or glycoprotein to slowly dissociate from the column.
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391
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Lee YC. Treatment of congestive heart failure with beta-adrenergic blockers: a brief review of literature. MARYLAND MEDICAL JOURNAL (BALTIMORE, MD. : 1985) 1998; 47:67-71. [PMID: 9524413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The importance of the adrenergic nervous system in support of hemodynamics in patients with congestive heart failure has been known for a long time. Thus, when beneficial effects of beta-blocker therapy in patients with resistant congestive heart failure were reported more than two decades ago, such an approach was deemed counterintuitive. Despite the skepticism, numerous reports, including well-planned, randomized studies, confirmed the beneficial effects of various beta-blockers on congestive heart failure. Recently, a new generation of beta-blocker, carvedilol (Coreg), which combines nonselective beta-blocking and vasodilating properties, was cleared by the U.S. Food and Drug Administration for the treatment of congestive heart failure. This article is a brief historical review of the literature regarding the use of beta-blockers for the treatment of congestive heart failure.
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392
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Chang YL, Yao YT, Wang NS, Lee YC. Segmental necrosis of small bronchi after prolonged intakes of Sauropus androgynus in Taiwan. Am J Respir Crit Care Med 1998; 157:594-8. [PMID: 9476878 DOI: 10.1164/ajrccm.157.2.9704040] [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: 02/06/2023] Open
Abstract
Since 1994 an endemic of chronic obstructive pulmonary disease (COPD) has developed in Taiwan after a prevalent use of a body-weight-reducing vegetable, Sauropus androgynus (SA). All conventional treatments for COPD, including steroids and bronchodilators, had been ineffective. Studies of limited lung biopsy specimens from these patients revealed bronchiolitis obliterans. A few patients died, but many developed protracted chronic respiratory failure. Because of the chronic debilitation and ineffective conventional treatments, single lung transplants were performed as the last resort in four patients. The excised lungs revealed focal fibromuscular sclerosis and obliteration of bronchial arteries in the wall of large bronchi 4 to 5 mm in diameter with segmental necrosis of bronchi 2 to 4 mm in diameter. Bronchi immediately proximal to the necrotic zone showed fibrosis and atrophy of cartilage, bronchial glands, and smooth muscle cells; bronchioles immediately distal showed obstruction or dilatation. Most bronchi larger than 5 mm, pulmonary vessels, small bronchioles, and alveoli were little altered. The pathologic changes were most consistent with segmental ischemic necrosis of bronchi at the water-shed zone of bronchial and pulmonary circulation. The specific etiologic agent and detail of pathogenesis of this SA-related COPD needs further investigation.
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393
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Brown MP, Toptygin D, Lee KB, Animashaun T, Hughes RC, Lee YC, Brand L. The tryptophan fluorescence of Tetracarbidium conophorum agglutinin II and a solution-based assay for the binding of a biantennary glycopeptide. JOURNAL OF PROTEIN CHEMISTRY 1998; 17:149-59. [PMID: 9535277 DOI: 10.1023/a:1022583617208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The plant lectin Tetracarbidium conophorum agglutinin II binds to glycoproteins and glycopeptides in a structurally specific manner [Animashaun et al., (1994) Glycoconjugate J. 11, 299-303]. We have characterized the steady-state and time-resolved fluorescence of the tryptophan residues of this lectin. The fluorescence (lambda[ex] = 295 nm, lambda[em] = 350 nm) decay is complex and can be described by four decay times with the following values: tau1 = 7.4 nsec, alpha1 = 0.22; tau2 = 2.9 nsec, alpha2 = 0.25: tau3 = 1.0 nsec, alpha3 = 0.34, tau4 = 0.2 nsec, alpha4 = 0.18. The addition of a biantennary glycopeptide (carbohydrate sequence [see text]) to the lectin results in a quench and an 8 nm blue shift of the emission spectrum. The effect is saturable, and is described by an association constant of 1.8 x 10(5) M(-1). The tryptophan fluorescence of Tetracarbidium conophorum agglutinin II may therefore be utilized to characterize thermodynamically the binding interactions between this lectin and complex glycoprotein.
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394
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Takahashi N, Lee KB, Nakagawa H, Tsukamoto Y, Masuda K, Lee YC. New N-glycans in horseradish peroxidase. Anal Biochem 1998; 255:183-7. [PMID: 9451502 DOI: 10.1006/abio.1997.2463] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We describe here the structures of several new N-glycan oligosaccharides from horseradish peroxidase (HRP). Glycopeptides from HRP were digested with glycoamidase A (from sweet almond) to release the N-glycans. The oligosaccharides were reductively aminated with 2-aminopyridine, and separated by high-performance liquid chromatography on octadecylsilyl- and amide-silica columns for two-dimensional mapping (Tomiya et al., Anal. Biochem. 171, 73-90, 1988). The N-glycans were also analyzed by electrospray ionization mass spectrometry. Two different lots of HRP showed a considerable difference in their N-glycan composition.
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395
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Wang LX, Pavlova NV, Yang M, Li SC, Li YT, Lee YC. Synthesis of aryl 3'-sulfo-beta-lactosides as fluorogenic and chromogenic substrates for ceramide glycanases. Carbohydr Res 1998; 306:341-8. [PMID: 9648244 DOI: 10.1016/s0008-6215(97)10082-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We have previously reported that 4-methylumbelliferyl 6'-O-benzyl-beta-lactoside (2) is a useful substrate for a fluorometric assay of ceramide glycanase (CGase) (L.-X. Wang, N. V. Pavlova, S.-C. Li, Y.-T. Li and Y. C. Lee, Glycoconjugate J., 13 (1996) 359-365). The introduction of a 6-O-benzyl group at the terminal Gal efficiently protected the substrate from its hydrolysis by exo-galactosidase, permitting the assay of CGase in crude biological materials. However, a drawback of this substrate is its low water-solubility and relatively high Km (at a mM level). Introduction of a sulfate group into 4-methylumbelliferyl beta-lactoside (1) led to the formation of 4-methylumbelliferyl 3'-O-sulfo-beta-lactoside (3), which was found to be a more effective substrate than 2. Moreover, the presence of a 3'-O-sulfate group not only increases the water solubility tremendously, but also protects the substrate from cleavage by exo-beta-galactosidase as the 6'-O-benzyl group in 2 does. In addition to the fluorogenic substrate (3), two sulfated chromogenic substrates, N-tetradecanoyl-4-O(3'-sulfo-beta-lactosyl)-3-nitro-L-tyrosine methyl ester (9) and 2-N-(tetradecanoylamino)-4-nitro-phenyl 3'-sulfo-beta-lactoside (12), were synthesized and their suitability for a photometric assay of CGase was evaluated. Substrates 9 and 12, with a long fatty acid chain attached to the aglycon part, have a Km value close to that of the natural substrate GM1 (at a microM level).
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396
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Kim SH, Cha IH, Kim KS, Kim YH, Lee YC. Cloning and sequence analysis of another Shiga-like toxin IIe variant gene (slt-IIera) from an Escherichia coli R107 strain isolated from rabbit. Microbiol Immunol 1997; 41:805-8. [PMID: 9403506 DOI: 10.1111/j.1348-0421.1997.tb01931.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: 02/05/2023]
Abstract
An Escherichia coli R107 strain (O26 serotype) producing a Shiga-like toxin IIe variant (SLT-IIera) was isolated from the mesenteric lymph node of a freshly dead rabbit carcass. The entire structural gene for this SLT-IIera was cloned from chromosomal DNA by PCR using primers based on previously published slt-IIe sequences. Nucleotide sequence analysis indicated that the slt-IIera gene was very similar to slt-IIe (formerly called slt-IIv) from E. coli strains S1191 and 412; five and one nucleotide changes were detected in A and B subunits, respectively, which resulted in changes in amino acid sequences of the corresponding subunits by three and one residues. Recombinant SLT-IIera and SLT-IIe produced using an E. coli host-vector system showed similar cytotoxicity, suggesting that the variations in the structural gene of SLT-IIera have no significant effect on cytotoxic level.
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397
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Sivan E, Lee YC, Wu YK, Reece EA. Free radical scavenging enzymes in fetal dysmorphogenesis among offspring of diabetic rats. TERATOLOGY 1997; 56:343-9. [PMID: 9485543 DOI: 10.1002/(sici)1096-9926(199712)56:6<343::aid-tera1>3.0.co;2-x] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent studies have suggested that the fetal dysmorphogenesis in diabetic pregnancies is associated with an increase in embryonic oxygen-free radicals. This excess of oxygen-free radicals may result from either overproduction or decreased clearance by the enzymatic scavenging mechanism. However, there are no in vivo data on the activity of embryonic oxygen-free radical scavenging enzymes. The purpose of the current study is to investigate whether this increase in embryonic oxygen-free radicals is the result of a change in the activity of the fetal oxygen-free radical scavenging/antioxidant enzymes during pregnancy complicated by maternal diabetes in an in vivo rat model. Thirty-six Sprague-Dawley rats were randomly assigned to one of two study groups: nondiabetic control and an untreated diabetic group. On day 12, fetuses were examined for crown-rump lengths, somite numbers, and external anomalies. The activity of fetal oxygen-free radical scavenging enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), were determined. The untreated diabetic group of rats had a significantly higher mean blood glucose level than that of the nondiabetic controls and also a significantly lower weight gain, higher resorption rate, smaller embryonic size with lower total protein content, and a approximately 6-fold increase in the rate of fetal neural tube defects compared to the nondiabetic controls. Superoxide dismutase activity was significantly reduced in the embryos with neural tube defects regardless of maternal diabetic status (2.25 +/- 0.83 vs. 1.17 +/- 0.04 u/mg protein; P < 0.05). Glutathione peroxidase and catalase activity were significantly reduced in malformed versus normal-formed embryos of nondiabetic mothers (GPX-2.68 +/- 1.15 vs. 4.46 +/- 1.12 mu/mg protein, CAT -1.67 +/- 0.53 vs 2.49 +/- 0.61 u/mg protein respectively; P < 0.01). However, overall catalase activity was increased in embryos of diabetic mothers as compared to controls. Two-way analysis of variance identified fetal malformations as the variance associated with reduced fetal SOD activity, whereas maternal diabetes was associated with the increase in fetal catalase activity. Neither neural tube defect nor maternal diabetes was found to be the variable affecting fetal GPX activity, Fetal oxygen-free radical scavenging enzymes respond differently to the adverse environment created by maternal diabetes during pregnancy. Defects in embryonic SOD and catalase activity, regardless of maternal diabetic status, may reduce the ability of the fetus to clear free oxygen radicals, thereby exposing it to an increased oxidative load that may cause fetal dysmorphogenesis. The diabetic state of the mothers did not decrease embryonic activity of any of the scavenging enzymes. Therefore, although excess oxidative load, as observed in diabetes, may cause tissue injury and embryopathy, the mechanism does not appear to be a diabetes-induced reduction in the action of the scavenging enzymes.
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398
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Kim DW, Lee YC, Matsuzawa H. Role of the COOH-terminal pro-sequence of aqualysin I (a heat-stable serine protease) in its extracellular secretion by Thermus thermophilus. FEMS Microbiol Lett 1997; 157:39-45. [PMID: 9418238 DOI: 10.1111/j.1574-6968.1997.tb12750.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Aqualysin I is a subtilisin-type serine protease secreted into the medium by Thermus aquaticus YT-1. Thermus thermophilus cells harboring a plasmid for the aqualysin I precursor secreted pro-aqualysin I with the C-terminal pro-sequence into the culture medium, and the precursor was then processed to the mature enzyme during the cultivation. However, the extracellular levels of aqualysin I in T. thermophilus cells harboring plasmids for deletion mutants as to the C-terminal pro-sequence were about 10-20% in comparison with the level of wild-type. Only the mature enzyme could be detected in the medium, while pro-aqualysin I with the C-terminal pro-sequence could not. These results suggest that the C-terminal pro-sequence of aqualysin I plays an important role in the extracellular secretion of aqualysin I.
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399
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Lee YC, Simamora P, Yalkowsky SH. Systemic delivery of insulin via an enhancer-free ocular device. J Pharm Sci 1997; 86:1361-4. [PMID: 9423146 DOI: 10.1021/js970191c] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Sodium insulin and zinc insulin ocular devices are developed for the systemic delivery of insulin. The devices consist of Gelfoam (absorbable gelatin sponge, USP) as an insulin carrier and do not contain any surfactant or absorption enhancer. Sodium insulin was dissolved in either distilled water, 30% ethanol, or 10% acetic acid for either eyedrop or device preparations. Because of its low solubility in water and aqueous ethanol solution, zinc insulin was dissolved in 10% acetic acid-water solution for eye devices preparation. Commercially available Humulin R was selected as another source of zinc insulin and was used as an eyedrop as well as one device preparation. Only 10% acetic acid solution-treated insulin devices produce significant blood glucose reduction. The dose of insulin used in this study is < 50% of that used in the reported insulin devices.
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400
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Lee YC, Cheon KT, Rhee YK. Changes of soluble ICAM-1 levels in serum and bronchoalveolar lavage fluid from patients with atopic bronchial asthma after allergen challenge. J Asthma 1997; 34:405-12. [PMID: 9350157 DOI: 10.3109/02770909709055382] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Leukocyte-endothelial cell interaction is essential for leukocyte infiltration into inflammatory sites. Initiation of adhesion is through the up-regulated expression of adhesion molecules in the endothelium or epithelium and the activation of adhesion molecules on leukocytes. To our knowledge, there have been few reports concerning soluble intercellular adhesion molecule-1 (sICAM-1) in patients with atopic bronchial asthma after allergen challenge. If the levels of sICAM-1 vary between bronchial asthma patients and normal controls, this variance would be useful to assess the state of this disease. Therefore, we measured the levels of sICAM-1 in sera from 17 patients with atopic bronchial asthma and normal control subjects. Levels of sICAM-1 in sera from bronchial asthma patients in prechallenge conditions were higher than in normal control subjects. Levels of sICAM-1 in sera from bronchial asthma patients 8 hr after challenge were higher than those in sera obtained during prechallenge periods. sICAM-1 levels in bronchoalveolar lavage (BAL) fluids from bronchial asthma patients 8 hr after challenge were higher than at 30 min after challenge. These results suggest that higher levels of sICAM-1 in sera and BAL fluids reflect the up-regulation of ICAM-1 expression in allergic bronchial asthma and these high levels may contribute to the pathogenesis of atopic bronchial asthma.
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