501
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Chin TM, Lin SB, Lee SY, Chang ML, Cheng AY, Chang FC, Pasternack L, Huang DH, Kan LS. "Paper-clip" type triple helix formation by 5'-d-(TC)3Ta(CT)3Cb(AG)3 (a and b = 0-4) as a function of loop size with and without the pseudoisocytosine base in the Hoogsteen strand. Biochemistry 2000; 39:12457-64. [PMID: 11015227 DOI: 10.1021/bi0004201] [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: 11/30/2022]
Abstract
The formation of a DNA "paper-clip" type triple helix (triplex) with a common sequence 5'-d-(TC)(3)T(a)()(CT)(3)C(b)()(AG)(3) (a and b = 0-4) was studied by UV thermal melting experiments and CD spectra. These DNA oligomers form triplexes and duplexes under slightly acidic and neutral conditions, respectively. The stability of the formed triplexes (at pH 4.5) or duplexes (at pH 7.0 or 8.0) does not vary significantly with the size of the loops (a and b = 1-4). At pH 6.0, the triplex stability is, however, a function of a and b. It is also interesting to note that the oligomer 5'-d-(TC)(3)(CT)(3)(AG)(3) (a and b = 0) forms a stable triplex at pH 4.5 with a slightly lower T(m) value, due to dissociation of a base triad at one end and a distorted base triad at the other, observed by (1)H NMR. Thus, we have here a model system, 5'-d-(TC)(3)T(a)(CT)(3)C(b)(AG)(3), that could form a triplex effectively with (a and b = 1-4) and without (a and b = 0) loops under acidic conditions. In addition, the triplex formation of oligomers with replacement of one, two, or three 2'-deoxycytidine in the Hoogsteen strand by either 2'-deoxypseudoisocytidine (D) or 2'-O-methylpseudoisocytidine (M) was also studied in the sequence 5'-d-(TX)(3)T(2)(CT)(3)C(2)(AG)(3) (where X is C, D, or M). Both CD spectra and UV melting results showed that only D3 [(TX)(3) = (TD)(3)] and M3 [(TX)(3) = (TM)(3)] were able to form the paper-clip structure under both neutral and acidic conditions. This is because the N(3)H of a pseudoisocytosine base can serve as a proton donor without protonation. We hereby proved that the 2'-deoxypseudoisocytidine, similar to 2'-O-methylpseudoisocytidine, could replace 2'-deoxycytidine in the Hoogsteen strand to provide triplex formation at neutral pH.
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502
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Levy-Wilson B, Paulweber B, Antes TJ, Goodart SA, Lee SY. An open chromatin structure in a liver-specific enhancer that confers high level expression to human apolipoprotein b transgenes in mice. MOLECULAR CELL BIOLOGY RESEARCH COMMUNICATIONS : MCBRC 2000; 4:206-11. [PMID: 11409913 DOI: 10.1006/mcbr.2001.0279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A number of DNaseI-hypersensitive (DH) sites have been mapped within a regulatory region situated upstream of the human apolipoprotein B (apoB) promoter (-5262 to -899) that is required for high level expression of human apoB transgenes in the livers of mice. These DH sites were observed in nuclei from transcriptionally active liver-derived HepG2 cells, but were absent from transcriptionally inactive HeLa cell nuclei. Several nuclear protein binding sites were detected in the DNaseI-hypersensitive region by DNaseI footprinting with HepG2 nuclear extracts, representing putative binding sites for the liver-specific activators. The locations of binding sites for these transcription factors were revealed via computer analysis of the DNA sequence of this region against a transcription factor database. Many micrococcal nuclease hypersensitive (MH) sites were also observed in nuclei from HepG2 cells but not in HeLa cell nuclei, implying that in hepatic cells, nucleosomes are either absent or have been displaced from this region by the liver-specific transcriptional activators, as inferred by the correspondence between the DH sites, the MH sites and the footprints.
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503
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Muramatsu N, Lee SY, Alexander JA. Hospital provision of institutional long-term care: pattern and correlates. THE GERONTOLOGIST 2000; 40:557-67. [PMID: 11037934 DOI: 10.1093/geront/40.5.557] [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: 11/14/2022] Open
Abstract
PURPOSE This study examined the pattern and correlates of institutional long-term care provision among U.S. community hospitals, differentiating two categories of services: (1) skilled nursing and rehabilitation (SN-R) and (2) other long-term care (O-LTC). DESIGN AND METHODS Multinomial logistic regression analysis was used to examine the associations of hospital and community characteristics with the pattern of long-term care provision (SN-R only, O-LTC only, both SN-R and O-LTC, and None) among 3,842 hospitals. RESULTS The pattern of long-term care provision was significantly associated with hospitals' mission (for-profit and teaching status) and their internal and external resources. IMPLICATIONS Results suggest the importance of considering hospital and community characteristics in predicting the impact of policy changes and in envisioning the role of hospitals in long-term care.
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504
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Kim W, Lee SY, Kim SW, Kwak JY, Kang SK, Park SK. Renal infarction in a patient with von Willebrand disease. Nephrol Dial Transplant 2000; 15:1711-3. [PMID: 11007855 DOI: 10.1093/ndt/15.10.1711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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505
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Shin MH, Lee SY. Proteolytic activity of cysteine protease in excretory-secretory product of Paragonimus westermani newly excysted metacercariae pivotally regulates IL-8 production of human eosinophils. Parasite Immunol 2000; 22:529-33. [PMID: 11012979 DOI: 10.1046/j.1365-3024.2000.00337.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study investigated the effect of the excretory-secretory product (ESP) of Paragonimus westermani newly excysted metacercariae (PwNEM) on IL-8 production of human mature eosinophils. Treatment of eosinophils with lower concentrations (0.3 and 1 microg/ml) of the ESP significantly (P < 0.01) induced IL-8 production, whereas treatment of cells with higher concentrations (3 and 10 microg/ml) did not. This effect of the ESP was concentration-dependent. Interestingly, the amount of IL-8 production released into the culture supernatants was inversely correlated with the rate of eosinophil survival. When eosinophils were cultured with the same concentrations of the ESP for 24 h, the ESP resulted in eosinophil death in a dose-dependent manner. To investigate whether high proteolytic activity of proteases in the ESP could cause little production of IL-8, 10 microg/ml of ESP was pretreated with heat at 100 degrees C for 10 min or 56 degrees C for 30 min to reduce its proteolytic activity. IL-8 production of eosinophils incubated with heat-treated ESP was markedly increased comparable to that of cells treated with the lowest concentration used in this study. These findings suggest that the protease in the ESP of PwNEM pivotally regulates IL-8 production by controlling of eosinophil survival, depending on the amount of ESP released in vivo. Thus, the cysteine protease in the ESP of PwNEM could provide a novel role to control recruitment of inflammatory cells in larval-infected lesions in human paragonimiasis.
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506
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Lee SY. Postantibiotic effects and postantibiotic sub-MIC effects of amoxicillin on Streptococcus gordonii and Streptococcus sanguis. J Chemother 2000; 12:379-84. [PMID: 11128556 DOI: 10.1179/joc.2000.12.5.379] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Amoxicillin is one of the most frequently recommended antibiotics for prophylaxis of infective endocarditis in dental/oral procedures. In this study, the postantibiotic effect (PAE), postantibiotic sub-MIC (PASME) and sub-MIC effect (SME) of amoxicillin on oral streptococci, Streptococcus gordonii and Streptococcus sanguis, which are two of the major etiological agents in infective endocarditis, were investigated. The PAE was induced by 10 x MIC of amoxicillin for 2 h and the antibiotic was eliminated by washing. The PASMEs were studied by addition of 0.1, 0.2 and 0.3 x MICs during the postantibiotic phase of the bacteria, and the SMEs were studied by exposing bacteria to amoxicillin at the sub-MICs only. The PAE of amoxicillin was 2.0 h with S. gordonii DL1 and 0.7 h with S. sanguis MPC1. The PASME and SME of amoxicillin were observed both for S. gordonii DL1 and for S. sanguis MPC1. However, the durations of effects for S. sanguis MPC1 were shorter than those for S. gordonii DL1. The PASME values for both strains increased as the concentration of amoxicillin increased. The PASME values for both strains were substantially longer than the SME values. The present study illustrates the existence of PAE, PASME and SME for amoxicillin against S. gordonii and S. sanguis, thereby extending the pharmacodynamic advantages of amoxicillin for these bacteria in the prophylaxis procedures of infective endocarditis.
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507
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Gnjatic S, Nagata Y, Jager E, Stockert E, Shankara S, Roberts BL, Mazzara GP, Lee SY, Dunbar PR, Dupont B, Cerundolo V, Ritter G, Chen YT, Knuth A, Old LJ. Strategy for monitoring T cell responses to NY-ESO-1 in patients with any HLA class I allele. Proc Natl Acad Sci U S A 2000; 97:10917-22. [PMID: 11005863 PMCID: PMC27124 DOI: 10.1073/pnas.97.20.10917] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2000] [Indexed: 11/18/2022] Open
Abstract
NY-ESO-1 elicits frequent antibody responses in cancer patients, accompanied by strong CD8(+) T cell responses against HLA-A2-restricted epitopes. To broaden the range of cancer patients who can be assessed for immunity to NY-ESO-1, a general method was devised to detect T cell reactivity independent of prior characterization of epitopes. A recombinant adenoviral vector encoding the full cDNA sequence of NY-ESO-1 was used to transduce CD8-depleted peripheral blood lymphocytes as antigen-presenting cells. These modified antigen-presenting cells were then used to restimulate memory effector cells against NY-ESO-1 from the peripheral blood of cancer patients. Specific CD8(+) T cells thus sensitized were assayed on autologous B cell targets infected with a recombinant vaccinia virus encoding NY-ESO-1. Strong polyclonal responses were observed against NY-ESO-1 in antibody-positive patients, regardless of their HLA profile. Because the vectors do not cross-react immunologically, only responses to NY-ESO-1 were detected. The approach described here allows monitoring of CD8(+) T cell responses to NY-ESO-1 in the context of various HLA alleles and has led to the definition of NY-ESO-1 peptides presented by HLA-Cw3 and HLA-Cw6 molecules.
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508
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Rha SE, Sohn KM, Lee SY, Jung HS, Park SM, Kim KM. Pedunculated exogastric leiomyoblastoma presenting as a wandering abdominal mass. ABDOMINAL IMAGING 2000; 25:545-7. [PMID: 10931995 DOI: 10.1007/s002610000088] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We report the imaging findings in a case of pedunculated exogastric leiomyoblastoma presenting as a wandering abdominal mass. Ultrasound and computed tomography showed a large, mixed solid and cystic mass in the peritoneal cavity. Computed tomography clearly showed that the mass was connected to the stomach by a narrow stalk. Small bowel follow-through showed subtle extrinsic indentation of the gastric body. The mass wandered from the right to the left side of the peritoneal cavity during various radiologic examinations.
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509
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Park CJ, Park CB, Hong SS, Lee HS, Lee SY, Kim SC. Characterization and cDNA cloning of two glycine- and histidine-rich antimicrobial peptides from the roots of shepherd's purse, Capsella bursa-pastoris. PLANT MOLECULAR BIOLOGY 2000; 44:187-97. [PMID: 11117262 DOI: 10.1023/a:1006431320677] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two novel antimicrobial peptides were isolated and characterized from the roots of shepherd's purse, Capsella bursa-pastoris. These antimicrobial peptides, named shepherin I and shepherin II, consist of 28 and 38 amino acids, respectively, and are glycine- and histidine-rich peptides. Shepherin I and shepherin II have 67.9% and 65.8% (mol/mol) glycine, respectively, and 28.6% and 21.1% (mol/mol) histidine, respectively. Both shepherins have a Gly-Gly-His motif. These antimicrobial peptides exhibit antimicrobial activity against Gram-negative bacteria and fungi. Circular dichroism spectra of shepherin I and shepherin II showed that shepherin I and shepherin II in 50% trifluoroethanol have 66.7% and 75% random coils, respectively, without any alpha-helices. cDNA sequence analysis revealed that shepherin I and shepherin II are produced from a single polypeptide, designated shep-GRP, consisting of 120 amino acids; shep-GRP has five distinct domains, an amino-terminal putative signal peptide, a shepherin I, a linker dipeptide, a shepherin II and a carboxy-terminal peptide. Southern blot analysis indicates that the gene encoding shepherins belongs to a low-complexity gene family. Northern blot analysis revealed that transcripts of shep-GRP are present in roots but not in leaves and stems.
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MESH Headings
- Amino Acid Sequence
- Anti-Bacterial Agents/chemistry
- Anti-Bacterial Agents/isolation & purification
- Anti-Bacterial Agents/pharmacology
- Bacteria/drug effects
- Bacteria/growth & development
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- Brassicaceae/genetics
- Cell Division/drug effects
- Circular Dichroism
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Plant/genetics
- Fungi/drug effects
- Fungi/growth & development
- Gene Expression Regulation, Plant
- Glycine/genetics
- Histidine/genetics
- Microbial Sensitivity Tests
- Molecular Sequence Data
- Peptides
- Plant Proteins/genetics
- Plant Proteins/pharmacology
- Plant Roots/genetics
- Protein Isoforms/genetics
- Protein Isoforms/pharmacology
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Analysis, Protein
- Sequence Homology, Amino Acid
- Tissue Distribution
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510
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Rha SE, Lee JH, Lee SY, Park SM. Duodenal diaphragm associated with long-term use of nonsteriodal antiinflammatory drugs: a rare cause of duodenal obstruction in an adult. AJR Am J Roentgenol 2000; 175:920-1. [PMID: 10954512 DOI: 10.2214/ajr.175.3.1750920] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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511
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Choi YH, Lee WH, Lee Y, Kim JK, Lee SY, Park JE. Correlation between monocyte and T-lymphocyte activation markers in patients with acute coronary syndrome. JAPANESE HEART JOURNAL 2000; 41:605-15. [PMID: 11132167 DOI: 10.1536/jhj.41.605] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Evidence suggesting the involvement of activated monocytes and T-lymphocytes in the acute phase of coronary artery disease (CAD) has been increasing. But a detailed analysis of a correlation between monocyte and T-lymphocyte activation markers in CAD has not yet been done. We analyzed plasma C-reactive protein (CRP) levels and the expression levels of CD14 and CD11b on monocytes and the percentage of HLA-DR T-lymphocytes in 25 patients with acute coronary syndrome (ACS), 12 stable angina (SA) patients, and 23 control subjects using flow-cytometry. The expression of CD14 by monocytes was increased significantly in ACS patients (activation index 38.7 +/- 2.5, mean +/- SEM) in comparison to the control subjects (8.0 +/- 1.9) and the SA patients (16.9 +/- 3.9) (p < 0.001 and p < 0.01, respectively). The expression of CD11b by monocytes of ACS patients (4.6 +/- 0.6) was also increased significantly in comparison to control subjects (2.2 +/- 0.1) and the SA patients (2.2 +/- 0.3) (p < 0.001 for both). Also, a significantly higher percentage of HLA-DR positive T-lymphocytes (19.2 +/- 1.8 vs 13.5 +/- 1.2%, p < 0.05) was observed among ACS patients in comparison to control subjects. Significant increases in plasma CRP levels were also detected in ACS patients. Furthermore, there were statistically significant correlations among these activation markers. These results indicate that activation of inflammatory cells may play a role in the pathogenesis of ACS. The correlation between the activation status of monocytes and T-lymphocytes indicates that the activation of these immune cells is linked in such a way that activation of one type of cell may lead to the activation of another type of cell.
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512
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Lee SY, Lin CT, Dong DR, Huang HM, Shih YH. Acoustic emissions generated in aged dental composites using a laser thermoacoustic technique. J Oral Rehabil 2000; 27:774-85. [PMID: 11012853 DOI: 10.1046/j.1365-2842.2000.00589.x] [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: 11/20/2022]
Abstract
The heating up of dental composites by laser will produce acoustic emissions (AEs) that may be related to fracture mechanisms in the composites. It has been proved that the mechanical properties of dental composites are affected by storage in food simulating liquids, i.e. 75% ethanol, which has a solubility parameter approximating to that of bisphenol glycidyl dimethacrylate (BisGMA) resin. A new method was innovated to evaluate the laser-induced AEs in dental composites aged by 75% ethanol solution. Model systems (50/50 BisGMA/TEGDMA resin filled with 0% and 75 wt.% 5-10 microm silanized BaSiO6) as well as three commercial composites (Marathon One, Z100 and Herculite XRV) were used in this study. Nine samples acting as the control group were tested to establish the correlation of AEs to laser power. The effect of ageing by immersion in 75% ethanol on AEs and diametral tensile strength (DTS) was then evaluated. A quasi-continuous wave CO2 laser was used to heat up the composites. AEs of frequency 100-200 kHz were collected, filtered, recorded and processed using a 4610 Smart Acoustic Monitor. Burst patterns, which formally were assumed to be correlated to fracture mechanisms, were also identified from the data obtained at laser power > or = 5 W for commercial composites and > or = 4 W for model systems. Higher laser powers cause the AE to increase for all composites except unfilled model resin. AEs as a function of power for all aged systems were flat (< 100 events) below 4 W. Emissions then rose sharply to > 1000 events at 7.1 W. Statistically significant differences were found between the AEs obtained at 5 W (commercial composites) and those at 4.3 W (model systems) for material systems and storage times. Marathon One was less affected by the laser and an abrupt change in AE was found between days 0 and 7 of storage for all commercial composites. The AE value from the unfilled model resin was found to be significantly different from that of the model composites. However, they showed an increase in AEs with length of storage time, which was inversely associated with the decreased tendency of their immersed DTS values. Laser-induced AEs may be a valuable adjunct to conventional mechanical testing.
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513
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Huang HM, Pan LC, Lee SY, Chiu CL, Fan KH, Ho KN. Assessing the implant/bone interface by using natural frequency analysis. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2000; 90:285-91. [PMID: 10982948 DOI: 10.1067/moe.2000.108918] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE A number of techniques have been proposed for detecting the stability of dental implants. However, the clinical applicability of those methods is still limited. The purpose of this study was to evaluate a new innovative, noninvasive, minimum-contact method for the stability assessment of dental implants. STUDY DESIGN Natural frequency is a physical property of a structure, which is strongly related to its boundary conditions. In this study, a modal testing technique was carried out to measure the natural frequency of dental implants. The implants were fixed by a metal clamp stand and were excited to vibrate by an impulse hammer. A noncontact piezoelectric microphone then acoustically acquired the vibration responses of the implants. Natural frequencies of the tested implants were recorded under various clamping forces and clamping levels. RESULTS Natural frequencies of the tested implants were concentrated from 8 to 19 kHz under different boundary conditions. On the other hand, the natural frequency values decreased when boundary levels and boundary force were reduced. Linear relationships (P <.005) were found between response frequencies and the degree of implant stability. CONCLUSIONS Our results show that the boundary status of an implant can be monitored by detecting its natural frequency. A noncontact transducer used in this study can also serve as a useful tool for future clinical investigations.
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514
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Lee SY, Park LO, Suk SH. Role of fibrinogen covalently associated with cell membrane in blood-borne lung tumor colony formation of murine mammary carcinoma cells. Oncology 2000; 59:238-44. [PMID: 11053992 DOI: 10.1159/000012167] [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: 11/19/2022]
Abstract
The role of fibrinogen covalently associated with cell membrane in blood-borne lung tumor colony formation of murine mammary carcinoma cells in mice was studied. When mice were treated with prednisolone, their plasma fibrinogen levels profoundly increased. Hyperfibrinogenemia, induced by prednisolone treatment or plasma fibrinogen infusion of syngeneic mice, accelerated the coagulation time and significantly increased the number of lung tumor colonies of SCK tumor cells. Hypofibrinogenemia, induced by rabbit antisyngenic mouse fibrinogen immunoglobulin G or heparin infusion, markedly delayed coagulation time and prominently reduced the numbers of blood-borne lung tumor colonies of the tumor cells. SCK mammary carcinoma cells form a coating of fibrinogen on their surfaces in a medium containing fibrinogen. This coating is cross-linked in a manner characteristic of catalysis by tumor cell membrane-bound transglutaminase K. The fibrinogen coating on the surface of these tumor cells functions to protect against autologous lymphokine-activated killer cells. These results provide information on the impact of fibrin stability on blood-borne lung tumor colony formation of SCK mammary carcinoma cells.
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515
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Horikawa T, Yoshizaki T, Sheen TS, Lee SY, Furukawa M. Association of latent membrane protein 1 and matrix metalloproteinase 9 with metastasis in nasopharyngeal carcinoma. Cancer 2000; 89:715-23. [PMID: 10951332 DOI: 10.1002/1097-0142(20000815)89:4<715::aid-cncr1>3.0.co;2-9] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Nasopharyngeal carcinoma (NPC) is a highly metastatic carcinoma whose consistent association with Epstein-Barr virus (EBV) has been established. Latent membrane protein 1 (LMP1), an EBV membrane protein expressed in latent infection, is considered to be the EBV oncoprotein. Matrix metalloproteinase 9 (MMP9), one of the MMP families, degrades Type IV collagen, a major component of extracellular matrix and is believed to be crucial for cancer invasion and metastasis. Although MMP9 is reported to be expressed in a variety of cancers, no reports concerning NPC have been published to date to the authors' knowledge. Recently, the authors have shown that LMP1 induces MMP9 in vitro cell line, which suggests the possibility of a mechanism in which LMP1 of EBV contributes to the metastasis and tumorigenesis of NPC by the induction of MMP9. METHODS The expressions of LMP1 and MMP9 were immunohistochemically examined in 38 NPC sections, and the relation of these proteins were statistically analyzed. The authors also analyzed the associations of these proteins with clinical features. RESULTS Both LMP1 and MMP9 proteins were predominantly immunolocalized in cancer nests. The expression of MMP9 showed a significant positive correlation with the expression of LMP1 (r = 0.75; P < 0.0001). Also, the expression of MMP9 correlated with lymph node metastasis (P = 0. 0004). CONCLUSIONS The results suggest that the induction of MMP9 by LMP1 contributes to the metastatic potential of NPC.
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516
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Ahn WS, Park SJ, Lee SY. Production of Poly(3-hydroxybutyrate) by fed-batch culture of recombinant Escherichia coli with a highly concentrated whey solution. Appl Environ Microbiol 2000; 66:3624-7. [PMID: 10919830 PMCID: PMC92194 DOI: 10.1128/aem.66.8.3624-3627.2000] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fermentation strategies for the production of poly(3-hydroxybutyrate) (PHB) from whey by recombinant Escherichia coli strain CGSC 4401 harboring the Alcaligenes latus polyhydroxyalkanoate (PHA) biosynthesis genes were developed. The pH-stat fed-batch cultures of E. coli CGSC 4401 harboring pJC4, a stable plasmid containing the A. latus PHA biosynthesis genes, were carried out with a concentrated whey solution containing 280 g of lactose equivalent per liter. Final cell and PHB concentrations of 119.5 and 96.2 g/liter, respectively, were obtained in 37.5 h, which resulted in PHB productivity of 2.57 g/liter/h.
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517
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Hsu SC, Huang JJ, Sung JM, Wang MC, Tseng CC, Lee SY. Tumoural calcinosis associated with subclavian vein occlusion and hypercalcaemia in a haemodialysis patient. Nephrol Dial Transplant 2000; 15:1262-4. [PMID: 10910465 DOI: 10.1093/ndt/15.8.1262] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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518
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Lee SY, Lee JJ, Koh AC, Chee SP. Branch retinal artery occlusion secondary to a Hollenhorst plaque. Singapore Med J 2000; 41:401-4. [PMID: 11256349] [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
Retinal arterial circulation obstruction has serious implications. It may result in acute visual loss, but more significantly, it implies that the patient's systemic health needs further review and investigations in order to prevent severe and life-threatening consequences such as myocardial infarction and cerebrovascular accidents. We report a case of a patient with branch retinal artery occlusion with the presence of a Hollenhorst plaque.
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519
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Abstract
We report a case of recurrent parachordoma of the left anterior tibial region in a 64-year-old male patient. The tumor was a periosteal tender mass, and, histologically, displayed vague nodules of spindle to rounded eosinophilic cells embedded in a myxoid matrix. Large vacuolated (physalphorouslike) cells were noted as in sacrococcygeal chordoma. This tumor should be differentiated from myxoid chondrosarcoma, myxoid liposarcoma, chondromyxoid fibroma, and metastatic chordoma. The presence of physaliphorous cells in the tumor with positive immunoreactions caused by cytokeratin rules out the diagnosis of another myxoid tumor. The differential diagnosis from metastatic chordoma is basically made by clinicians. Even though parachordoma is usually regarded as a benign soft tissue neoplasm, two recurrences occurred in our case. Since the reported cases, including ours, have diverse clinical courses, it is essential to follow-up the patient carefully.
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520
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Huang FC, Ko SF, Lee SY. Meckel's diverticulum mimicking infantile colic: sonographic detection. JOURNAL OF CLINICAL ULTRASOUND : JCU 2000; 28:314-316. [PMID: 10867673 DOI: 10.1002/1097-0096(200007/08)28:6<314::aid-jcu10>3.0.co;2-n] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report a case of Meckel's diverticulum in a 6-month-old girl who presented with a 5-month history of chronic screaming but no symptoms or signs of intestinal obstruction. Infantile colic was the presumptive diagnosis. Abdominal sonography at 6 months of age demonstrated an abdominal mass with an anechoic center and a double-layered wall, surrounded by bowel loops. Abdominal CT and barium enema x-ray studies demonstrated nonspecific findings of a cystic mass with compression of adjacent bowel loops. Histologic examination of the resected mass revealed a Meckel's diverticulum with a perforation sealed off by the neighboring bowel and mesentery to form an inflammatory mass.
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521
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Li XM, Serebrisky D, Lee SY, Huang CK, Bardina L, Schofield BH, Stanley JS, Burks AW, Bannon GA, Sampson HA. A murine model of peanut anaphylaxis: T- and B-cell responses to a major peanut allergen mimic human responses. J Allergy Clin Immunol 2000; 106:150-8. [PMID: 10887318 DOI: 10.1067/mai.2000.107395] [Citation(s) in RCA: 317] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Peanut allergy affects 0.6% of the US population. At the present time, allergen avoidance is the only therapeutic option. Animal models of food-induced anaphylaxis would facilitate attempts to design novel immunotherapeutic strategies for the treatment of peanut allergy. OBJECTIVE The purpose of this study was to develop a murine model of IgE-mediated peanut hypersensitivity that closely mimics human peanut allergy. METHODS C3H/HeJ mice sensitized orally with freshly ground whole peanut and cholera toxin as adjuvant were challenged orally 3 and 5 weeks later with crude peanut extract. Anaphylactic reactions were determined. T- and B-cell responses to Ara h 1 and Ara h 2, the major peanut allergens, were characterized by evaluating splenocyte proliferative responses and IgE antibody concentrations. Furthermore, IgE antibodies in the sera of patients with peanut allergy and mice were compared for antibody binding to Ara h 2 isoforms and allergenic epitopes. RESULTS Peanut-specific IgE was induced by oral peanut sensitization, and hypersensitivity reactions were provoked by feeding peanut to sensitized mice. The symptoms were similar to those seen in human subjects. Ara h 1- and Ara h 2-specific antibodies were present in the sera of mice with peanut allergy. Furthermore, these Ara h 2-specific IgE antibodies bound the same Ara h 2 isoforms and major allergenic epitopes as antibodies in the sera of human subjects with peanut allergy. Splenocytes from mice with peanut allergy exhibited proliferative responses to Ara h 1 and Ara h 2. CONCLUSION This murine model of peanut allergy mimics the clinical and immunologic characteristics of peanut allergy in human subjects and should be a useful tool for developing immunotherapeutic approaches for the treatment of peanut allergy.
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522
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Kwak HS, Lee JM, Lee SY, Han YM, Kim CS, Moon WS, Yu HC. Pseudotumorous hyperplasia of the caudate lobe in the non-cirrhotic liver: MR and CT arterial portography appearance. HEPATO-GASTROENTEROLOGY 2000; 47:909-11. [PMID: 11020845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We describe the magnetic resonance image and computed tomographic arterial portography appearance of pseudotumorous hyperplasia in the caudate process of the caudate lobe in a non-cirrhotic patient. A prominent portal vein branch directly arising from the right main portal branch was seen in the center of the lesion on magnetic resonance imaging and computed tomographic arterial portography. We think that portal flow change of the caudate lobe by an anomalous portal branch may be correlated to pseudotumorous hyperplasia.
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523
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Abstract
The aims of this study were to observe the release of fluoride ions (F-) from GC-Fuji Lining-LC(R) glass-ionomer cement, to assess the diffusion process, and to measure fluoride diffusivity (D) in the set cement. Specimens of various dimensions and shapes, ranging from discs to cylindrical rods, were fabricated for both open and embedded modes of testing. In the open mode studies, specimens with different surface to volume ratios were selected and immersed in 37 degrees C distilled water. In the embedded mode studies, only one diametral surface of the rod-shaped specimens of different lengths and diameters was exposed. F- concentration was measured using a fluoride electrode. The storage solution was analysed at predetermined intervals hourly, daily, and weekly (up to 10 weeks). Immediately after each sampling, the old storage solution was discarded and replaced with new distilled water. F- release from the set cements was detectable (0.4-3.8 ppm, varied with sample geometry), even after a 10-week sampling interval. F- release was greater in ground set cements (0.37 ppm/mg powder) than in control samples of unmixed powder (0.01 ppm/mg powder) immersed for 1 h. Two mechanisms for F- release were proposed. One was short-term and involved rapid dissolution from the cement surface. The other was more gradual and resulted in the sustained diffusion of ions through the bulk cement, which can be modelled by applying a mathematical technique known as separation of variables to Fick's Second Law of Diffusion. The mean D of F- in embedded set cements of glass-ionomer was (1.4+/-0.5)x10-11 cm2/s, with higher apparent D observed in open mode samples [(7.6+/-1.4)x10-11 cm2/s].
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524
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Cho JH, Lee KB, Yong TS, Kim BS, Park HB, Ryu KN, Park JM, Lee SY, Suh JS. Subcutaneous and musculoskeletal sparganosis: imaging characteristics and pathologic correlation. Skeletal Radiol 2000; 29:402-8. [PMID: 10963426 DOI: 10.1007/s002560000206] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To document the imaging characteristics of subcutaneous and musculoskeletal sparganosis. DESIGN AND PATIENTS Ten patients with musculoskeletal sparganosis were examined, with a variety of imaging modalities including MRI (n=6), ultrasonography (n=8), plain radiography (n=7) and CT (n=1). Pathologic correlation was carried out in all cases. RESULTS Nine lesions involved soft tissues, of which seven were in the thigh, two in the trunk and one involved a vertebral body. The majority of the lesions in soft tissue were confined to the subcutaneous layer but two extended deep into underlying muscles. Sonography revealed low-echoic serpiginous tubular tracts (8/8), and an intraluminal echogenic structure (4/8). MRI revealed multiple serpiginous tubular tracts and peripheral rim enhancement. Two patients showed perilesional soft tissue edema. Pathologically, the lesion consisted of a larva surrounded by three layers of inflammation: an inner epithelioid granulomatous cell layer, middle chronic inflammatory cell layers, and an outer fibrous layer. CONCLUSION The study suggests that if serpiginous tubular tracts are seen at imaging studies, musculoskeletal sparganosis should be included in the differential diagnosis.
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525
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Lee SY, Lin CT, Keh ES, Pan LC, Huang HM, Shih YH, Cheng HC. Laser-induced acoustic emissions in experimental dental composites. Biomaterials 2000; 21:1399-408. [PMID: 10850935 DOI: 10.1016/s0142-9612(00)00043-0] [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: 11/15/2022]
Abstract
A laser thermoacoustic technique was innovated to evaluate laser-induced acoustic emissions (AEs) in experimental dental composites aged with 75% ethanol solution. Experimental composite systems of 75/25 BisGMA/TEGDMA resin filled with 0, 12.6, 30.0, and 56.5 vol% of 8-microm silanized and unsilanized BaSiO6 were analyzed. The sample size was 4.65 mm (diameter) x 0.5 mm (thick). Aging effects of immersing in 75% ethanol for up to 14 h on AEs were then evaluated. A continuous-wave CO2 laser was used to heat the samples. Acoustic emissions were collected as a function of filler fraction, laser power, silanization, and immersion time. Onset of burst-pattern acoustic signals characteristic of fracturing occurred at different laser powers for different tested groups. Acoustic emissions generally increased with laser power, in which lower laser powers produced low-amplitude (45-50 dB) signals; the amplitude distribution (50-85 dB) became more extensive as laser powers increased. After immersion, the lower laser powers could produce the same phenomenon. The higher the filler fraction, the fewer AEs generated. A large percentage AE reduction due to silanization was noted as a function of filler fraction. Unsilanized specimens showed more thermal damages than did silanized ones.
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