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Liu CP, Jiang K, Wu CH, Lee WH, Lin WJ. Detection of glutamic acid decarboxylase-activated T cells with I-Ag7 tetramers. Proc Natl Acad Sci U S A 2000; 97:14596-601. [PMID: 11106373 PMCID: PMC18964 DOI: 10.1073/pnas.250390997] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
CD4(+) T cells selected by the type 1 diabetes associated class II MHC I-A(g7) molecules play a critical role in the disease process. Multivalent MHC/peptide tetramers have been used to directly detect antigen-specific T cells. Detection of autoantigen-activated CD4(+) T cells with tetramers should be very helpful in the study of the roles of these cells in diabetes. We report here the generation of tetramers of I-A(g7) covalently linked to two glutamic acid decarboxylase (GAD) peptides and the detection of GAD peptide-activated T cells from nonobese diabetic (NOD) mice. The I-A(g7) heterodimers can form stable complexes with a covalently bound GAD peptide and can stimulate antigen specific T cells. Furthermore, I-A(g7)/GAD peptide tetramer can detect most if not all of the antigen-specific CD4(+) T cells from immunized NOD mice. Antigen-specific T cells detected by the tetramers can up-regulate their CD4 expression on the cell surface after being restimulated with the GAD peptides in vitro. In contrast, the tetramers can detect a percentage of T cells in lymph nodes and spleens and T cells infiltrating islets from nonimmunized mice that is not significantly above the background. Therefore, T cells specific for the GAD peptides are present in NOD mice at a frequency too low to be detected, but immunization of NOD mice can facilitate their detection by tetramers.
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Abstract
BRCA1 and BRCA2 are breast cancer susceptibility genes. Mutations within BRCA1 and BRCA1 are responsible for most familial breast cancer cases. Targeted deletion of Brca1 or Brca2 in mice has revealed an essential function for their encoded products, BRCA1 and BRCA2, in cell proliferation during embryogenesis. Mouse models established from conditional expression of mutant Brca1 alleles develop mammary gland tumors, providing compelling evidence that BRCA1 functions as a breast cancer suppressor. Human cancer cells and mouse cells deficient in BRCA1 or BRCA2 exhibit radiation hypersensitivity and chromosomal abnormalities, thus revealing a potential role for both BRCA1 and BRCA2 in the maintenance of genetic stability through participation in the cellular response to DNA damage. Functional analyses of the BRCA1 and BRCA2 gene products have established their dual participation in transcription regulation and DNA damage repair. Potential insight into the molecular basis for these functions of BRCA1 and BRCA2 has been provided by studies that implicate these two tumor suppressors in both the maintenance of genetic stability and the regulation of cell growth and differentiation.
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Chen A, Sheu LF, Shaio MF, Huang TH, Ding SL, Lee WH. Anti-idiotype antibody directly interferes with glomerular IgA immune complex deposition. Nephron Clin Pract 2000; 78:464-73. [PMID: 9578073 DOI: 10.1159/000044976] [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: 11/19/2022] Open
Abstract
Data from both animal and clinical studies suggest that anti-idiotype antibodies deposited in glomeruli may be involved in the pathogenesis of glomerulonephritis. This study was conducted to examine the role of a hybridoma-AB1-2-derived IgG anti-T15 idiotype (IgG anti-T15) in the immunopathogenesis of a short-term experimental IgA nephropathy. BALB/c mice (12/group) were administered intravenously with: (1) an equal mass (1 mg) of T15-hybridoma-derived IgA antiphosphorylcholine (PC) and PC-conjugated bovine serum albumin (BSA-PC) antigen; (2) 1 mg of IgA anti-PC, 1 mg of BSA-PC antigen, and 3 mg of IgG anti-T15, or (3) 1 mg of BSA-PC antigen alone. The mice were sacrificed 6 h after the injection. A 6-hour clearance study was performed. The initial phase of elimination of BSA-PC antigen in mice receiving IgA anti-PC/BSA-PC/IgG anti-T15 or those receiving the antigen alone was significantly faster than that in those receiving IgA anti-PC/BSA-PC (p < 0.001). There was no significant difference in the elimination rate of BSA-PC antigen between mice receiving IgA anti-PC/BSA-PC/IgG anti-T15 and those receiving BSA-PC antigen alone. The late phases of elimination of the BSA-PC antigen in mice receiving IgA anti-PC/BSA-PC/IgG anti-T15 showed somewhat similar to those of BSA-PC antigen in mice receiving IgA anti-PC/BSA-PC. Moreover, mice injected with IgA anti-PC/BSA-PC/IgG anti-T15 showed a significantly less glomerular BSA-PC antigen deposition than those injected with IgA anti-PC/BSA-PC (positive control), as demonstrated by light microscopy, autoradiography, and immunohistochemistry (each p < 0.001). It is inferred that the injected IgG anti-T15 could react with the IgA anti-PC in vivo, directly interfering with immune complex formation by the IgA anti-PC and BSA-PC antigen, thereby resulting in diminished glomerular deposition of the BSA-PC antigen. These findings suggest that an anti-idiotype antibody may be protective in the immunopathogenesis of IgA nephropathy, because of its inhibitory effect on glomerular trapping of an antigen.
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Chen A, Sheu LF, Ho YS, Lin YF, Chou WY, Chou TC, Lee WH. Experimental focal segmental glomerulosclerosis in mice. Nephron Clin Pract 2000; 78:440-52. [PMID: 9578071 DOI: 10.1159/000044974] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Although a lot of animal models of proteinuria have been established, proposals for the mechanisms of proteinuria are still controversial. In this work, during an 18-day trial, mice injected with a single dose of adriamycin (AD) rapidly showed combined glomerular albuminuria and immunoglobulinuria, progressively elevated levels of nitrite/nitrate in urine, hypercholesterolemia, abnormal renal function, segmentally or globally glomerular hyalinosis/sclerosis associated with tubular atrophy, enhanced glomerular deposition of immunoglobulins and fibrinogen, augmented expression of matrix components in the whole glomerular tuft, and loss of glomerular negative charge property. These laboratory and pathological features are comparatively similar to those of human focal segmental glomerulosclerosis in the advanced state. Juxtamedullary glomeruli appear to be more susceptible to the AD-related nephrotoxicity than those in the superficial renal cortex. A change in size-dependent glomerular permselectivity may precede a charge-dependent defect in glomeruli in this mouse model of proteinuria. Data in this study confirm the hypothesis of glomerular hyperfiltration involved in the pathogenesis of this chronic glomerulopathy associated with proteinuria in mice. In addition, nitric oxide may play a crucial role in the progression of the chronic glomerulopathy model.
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105
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Chen A, Sheu LF, Chou WY, Ho YS, Lin YF, Lin FG, Lee WH. Involvement of immunopathogenic mechanisms in a spontaneously occurring glomerulopathy in mice. Nephron Clin Pract 2000; 78:63-72. [PMID: 9453406 DOI: 10.1159/000044884] [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: 02/06/2023] Open
Abstract
Mice have been found to be susceptible to spontaneous renal localization of immune deposits. However, the significance of these immune deposits is still debated. We investigated the immunopathogenesis of a naturally occurring glomerulopathy associated with progressive proteinuria and glomerulosclerosis in 75 BALB/c mice. The mice were divided into five groups of 15 and killed at the age of 1, 3, 6, 12, or 18 months for laboratory and renal pathologic studies. These mice showed persistently increasing serum levels of immune complexes, a marked increase of glomerular immune deposits which were capable of fixing C3, and interstitial infiltration of lymphocytes and plasma cells, followed by the occurrence of proteinuria, mesangiopathy, and glomerulosclerosis. Our findings suggest that an immune system mediated process occurred in the kidneys of the mice tested.
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106
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Zheng L, Pan H, Li S, Flesken-Nikitin A, Chen PL, Boyer TG, Lee WH. Sequence-specific transcriptional corepressor function for BRCA1 through a novel zinc finger protein, ZBRK1. Mol Cell 2000; 6:757-68. [PMID: 11090615 DOI: 10.1016/s1097-2765(00)00075-7] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BRCA1 has been implicated in the transcriptional regulation of DNA damage-inducible genes that function in cell cycle arrest. To explore the mechanistic basis for this regulation, a novel human gene, ZBRK1, which encodes a 60 kDa protein with an N-terminal KRAB domain and eight central zinc fingers, was identified by virtue of its interaction with BRCA1 in vitro and in vivo. ZBRK1 binds to a specific sequence, GGGxxx CAGxxxTTT, within GADD45 intron 3 that supports the assembly of a nuclear complex minimally containing both ZBRK1 and BRCA1. ZBRK1 represses transcription through this recognition sequence in a BRCA1-dependent manner. These results thus reveal a novel corepressor function for BRCA1 and provide a mechanistic basis for the biological activity of BRCA1 through sequence-specific transcriptional regulation.
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Wu G, Lee WH, Chen PL. NBS1 and TRF1 colocalize at promyelocytic leukemia bodies during late S/G2 phases in immortalized telomerase-negative cells. Implication of NBS1 in alternative lengthening of telomeres. J Biol Chem 2000; 275:30618-22. [PMID: 10913111 DOI: 10.1074/jbc.c000390200] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Nijmegen breakage syndrome, a chromosomal instability disorder, is characterized in part by cellular hypersensitivity to ionizing radiation. The NBS1 gene product, p95 (NBS1 or nibrin) forms a complex with Rad50 and Mre11. Cells deficient in the formation of this complex are defective in DNA double-strand break repair, cell cycle checkpoint control, and telomere length maintenance. How the NBS1 complex is involved in telomere length maintenance remains unclear. Here we show that the C-terminal region of NBS1 interacts directly with a telomere repeat binding factor, TRF1, by both yeast two-hybrid and in vivo DNA-coimmunoprecipitation assays. NBS1 and Mre11 colocalize with TRF1 at promyelocytic leukemia (PML) nuclear bodies in immortalized telomerase-negative cell lines, but rarely in telomerase-positive cell lines. The translocation of NBS1 to PML bodies occurs specifically during late S to G(2) phases of the cell cycle and coincides with active DNA synthesis in these NBS1-containing PML bodies. These results suggest that NBS1 may be involved in alternative lengthening of telomeres in telomerase-negative immortalized cells.
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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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Cheng CM, Reinhardt RR, Lee WH, Joncas G, Patel SC, Bondy CA. Insulin-like growth factor 1 regulates developing brain glucose metabolism. Proc Natl Acad Sci U S A 2000; 97:10236-41. [PMID: 10954733 PMCID: PMC27834 DOI: 10.1073/pnas.170008497] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The brain has enormous anabolic needs during early postnatal development. This study presents multiple lines of evidence showing that endogenous brain insulin-like growth factor 1 (Igf1) serves an essential, insulin-like role in promoting neuronal glucose utilization and growth during this period. Brain 2-deoxy-d- [1-(14)C]glucose uptake parallels Igf1 expression in wild-type mice and is profoundly reduced in Igf1-/- mice, particularly in those structures where Igf1 is normally most highly expressed. 2-Deoxy-d- [1-(14)C]glucose is significantly reduced in synaptosomes prepared from Igf1-/- brains, and the deficit is corrected by inclusion of Igf1 in the incubation medium. The serine/threonine kinase Akt/PKB is a major target of insulin-signaling in the regulation of glucose transport via the facilitative glucose transporter (GLUT4) and glycogen synthesis in peripheral tissues. Phosphorylation of Akt and GLUT4 expression are reduced in Igf1-/- neurons. Phosphorylation of glycogen synthase kinase 3beta and glycogen accumulation also are reduced in Igf1-/- neurons. These data support the hypothesis that endogenous brain Igf1 serves an anabolic, insulin-like role in developing brain metabolism.
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110
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Kim HS, Choi JY, Jung AR, Jang KL, Lee WH, Choi WC, Crow TJ, Hyun BH. Assignment of the human RhoHP1 gene (ARHD) to chromosome 11q14.3 by radiation hybrid mapping. CYTOGENETICS AND CELL GENETICS 2000; 89:53. [PMID: 10894936 DOI: 10.1159/000015562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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111
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Li S, Ting NS, Zheng L, Chen PL, Ziv Y, Shiloh Y, Lee EY, Lee WH. Functional link of BRCA1 and ataxia telangiectasia gene product in DNA damage response. Nature 2000; 406:210-5. [PMID: 10910365 DOI: 10.1038/35018134] [Citation(s) in RCA: 246] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BRCA1 encodes a familial breast cancer suppressor that has a critical role in cellular responses to DNA damage. Mouse cells deficient for Brca1 show genetic instability, defective G2-M checkpoint control and reduced homologous recombination. BRCA1 also directly interacts with proteins of the DNA repair machinery and regulates expression of both the p21 and GADD45 genes. However, it remains unclear how DNA damage signals are transmitted to modulate the repair function of BRCA1. Here we show that the BRCA1-associated protein CtIP becomes hyperphosphorylated and dissociated from BRCA1 upon ionizing radiation. This phosphorylation event requires the protein kinase (ATM) that is mutated in the disease ataxia telangiectasia. ATM phosphorylates CtIP at serine residues 664 and 745, and mutation of these sites to alanine abrogates the dissociation of BRCA1 from CtIP, resulting in persistent repression of BRCA1-dependent induction of GADD45 upon ionizing radiation. We conclude that ATM, by phosphorylating CtIP upon ionizing radiation, may modulate BRCA1-mediated regulation of the DNA damage-response GADD45 gene, thus providing a potential link between ATM deficiency and breast cancer.
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112
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Lee WH, Ko YH, Kim DI, Lee BB, Park JE. Prevalence of foam cells and helper-T cells in atherosclerotic plaques of Korean patients with carotid atheroma. Korean J Intern Med 2000; 15:117-21. [PMID: 10992723 PMCID: PMC4531756 DOI: 10.3904/kjim.2000.15.2.117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Inflammation and activation of immune cells have important roles in the pathogenesis of atherosclerosis. We analyzed the involvement of various immune cells in the pathogenesis of atherosclerosis. METHODS We investigated the presence of foam cells, lymphocytes and killer cells in 11 atherosclerotic plaque specimens removed from Korean patients who underwent carotid endoarterectomy. Atherosclerotic plaques were analyzed by immunohistochemistry using monoclonal antibody specific to foam cells (anti-CD68), pan-T cells (anti-CD3), helper-T cells (anti-CD4), cytotoxic T cells (anti-CD8), granular component of killer cells (anti-TIA-1) and pan-B cells (anti-CD20). RESULTS Analysis revealed a general infiltration of immune cells not only in atherosclerotic plaques but also in the vascular wall adjacent to the plaque. Heavy infiltration of CD68+ macrophage was observed in all cases. In addition, significant infiltration of CD3+ T-lymphocytes was observed in all cases, while CD20+ B-cells were observed in only a few cases. Majority of the CD3+ cells was found to be CD4+ helper-T cells. CD8+ cytotoxic T cells and TIA-1+ cells were less prominent. CONCLUSION Analysis of the human atherosclerotic plaques suggested that helper-T cells and foam cells had a major role in the plaque development.
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Lee WH, Chen A, Chao DG, Harn HJ, Lin SZ. Malignant meningioma with rhabdoid transformation. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2000; 63:492-7. [PMID: 10925541] [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 report a rare case of recurrent meningioma with malignant change and rhabdoid transformation in a 54-year-old woman who presented with severe headache and progressive weakness of the right extremities. The patient had a history of atypical meningioma and had undergone a craniotomy to remove a tumor nine years earlier. We discuss the distinctive morphologic, immunohistochemical staining and ultrastructural features of a recurrent malignant meningioma. A meningioma with rhabdoid transformation may indicate aggressive biologic and clinical behavior of the tumor.
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Abstract
In recent decades, there has been an increase in both the number of sympathectomy techniques, as well as the surgical findings of sympathetic anatomy. Currently the advanced technique of C-arm guided percutaneous thoracic chemo-sympathectomy is widely used for the treatment of palmar hyperhidrosis. However, a better understanding of chemical agents in sympathectomy is required. In this study, chemo-sympathectomy was performed in cats, using alcohol, glycerol and various concentrations of phenol, to determine the chronic neurotoxic effects of these chemical agents on the stellate ganglia. The stellate ganglia of 24 cats were exposed under endotracheal general anesthesia, then injected with about 0.02 ml of absolute alcohol, glycerol and phenol (10%, 25%, 50%, and 75% concentration) solutions, respectively. The stellate ganglia were taken for histological examination three weeks after the chemical injection. The results showed that the degenerative changes in the cytoplasm and nucleus of ganglionic cells and intercellular tissue were moderate and relatively moderate after the injection of alcohol and glycerol, respectively. Meanwhile, the stellate ganglia revealed mild, relatively moderate, serious and extremely serious degeneration after injection of 10%, 25%, 50%, and 75% phenol, respectively. In conclusion, we recommend a high concentration of phenol, in the least volume, as a chemical agent for clinical injection in the upper thoracic sympathetic ganglion.
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115
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Stewart WC, Sharpe ED, Day DG, Kolker AE, Konstas AG, Lee WH, Rieser JC, Chopra H, Holmes KT. Comparison of the efficacy and safety of latanoprost 0.005% compared to brimonidine 0.2% or dorzolamide 2% when added to a topical beta-adrenergic blocker in patients with primary open-angle glaucoma or ocular hypertension. J Ocul Pharmacol Ther 2000; 16:251-9. [PMID: 10872922 DOI: 10.1089/jop.2000.16.251] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The purpose of this study was to evaluate the ocular hypotensive efficacy and safety of latanoprost 0.005% (Xalatan, Pharmacia & Upjohn), brimonidine (Alphagan, Allergan), and dorzolamide (Trusopt, Merck Inc.) when added to a beta-blocker in patients with ocular hypertension or primary open-angle glaucoma. This was a multicenter, retrospective analysis which included all reviewed patient records in which latanoprost, brimonidine or dorzolamide were added to a beta-blocker for at least three months. Patients who were treated for less than three months, who failed therapy due to ineffectiveness of the medicine or an adverse event also were included. The study included 141 patients. Latanoprost (n = 50) showed an intraocular pressure of 16.7 +/- 3.3 mm Hg (-6.3 +/- 4.1 mm Hg, P < 0.001), brimonidine (n = 24) 17.4 +/- 4.9 mm Hg (-4.2 +/- 4.5 mm Hg, P < 0.001), and dorzolamide (n = 67) 20.1 +/- 6.1 mm Hg (-3.1 +/- 5.1 mm Hg, P < 0.001) at three months. A significant difference was observed in the absolute level of intraocular pressure (P < 0.005) and the change from baseline between groups (P < 0.005) at three months. A significant difference was observed between groups in the success rate of therapy between latanoprost (70%), brimonidine (58%) and dorzolamide (40%) (P = 0.008). No significant differences were observed between groups for rate or type of adverse events leading to discontinued therapy. This study showed that latanoprost, when added to beta-blockers, compares favorably in ocular hypotensive efficacy and is similar in safety to brimonidine and dorzolamide.
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116
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Lee WH, Charles SJ. Acute retinal necrosis following chickenpox in a healthy 4 year old patient. Br J Ophthalmol 2000; 84:667-8. [PMID: 10896413 PMCID: PMC1723501 DOI: 10.1136/bjo.84.6.667a] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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117
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Zheng L, Chen Y, Riley DJ, Chen PL, Lee WH. Retinoblastoma protein enhances the fidelity of chromosome segregation mediated by hsHec1p. Mol Cell Biol 2000; 20:3529-37. [PMID: 10779342 PMCID: PMC85645 DOI: 10.1128/mcb.20.10.3529-3537.2000] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Retinoblastoma protein (Rb) plays important roles in cell cycle progression and cellular differentiation. It may also participate in M phase events, although heretofore only circumstantial evidence has suggested such involvement. Here we show that Rb interacts, through an IxCxE motif and specifically during G(2)/M phase, with hsHec1p, a protein essential for proper chromosome segregation. The interaction between Rb and hsHec1p was reconstituted in a yeast strain in which human hsHEC1 rescues the null mutation of scHEC1. Expression of Rb reduced chromosome segregation errors fivefold in yeast cells sustained by a temperature-sensitive (ts) hshec1-113 allele and enhanced the ability of wild-type hsHec1p to suppress lethality caused by a ts smc1 mutation. The interaction between Hec1p and Smc1p was important for the specific DNA-binding activity of Smc1p. Expression of Rb restored part of the inactivated function of hshec1-113p and thereby increased the DNA-binding activity of Smc1p. Rb thus increased the fidelity of chromosome segregation mediated by hsHec1p in a heterologous yeast system.
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Usmani BA, Shen R, Janeczko M, Papandreou CN, Lee WH, Nelson WG, Nelson JB, Nanus DM. Methylation of the neutral endopeptidase gene promoter in human prostate cancers. Clin Cancer Res 2000; 6:1664-70. [PMID: 10815884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Neutral endopeptidase 24.11 (NEP) is a cell surface peptidase expressed by prostatic epithelial cells that cleaves and inactivates neuropeptide growth factors implicated in the growth of androgen-independent prostate cancer (PC). Decreased NEP expression in hormone-refractory metastatic PCs can result from hormonal therapies because NEP transcription is induced by androgens and down-regulated by androgen withdrawal. NEP is encoded by a gene that contains a 5' CpG island spanning a transcriptional regulatory region. In this study, we investigate whether DNA hypermethylation of the NEP promoter accompanies decreased NEP expression in PC cell lines and whether it occurs in human PC tissues in vivo. DNA isolated from PC cell lines and from normal and neoplastic human prostate tissues was restriction-digested with a methylation-sensitive restriction endonuclease and analyzed by Southern blot using a 5' sequence-specific NEP probe. Methylation-specific PCR was performed using PCR primers designed to discriminate between methylated and unmethylated alleles, and reverse transcription-PCR using NEP-specific primers was performed on cDNA extracted from PC cells treated with 5-aza-2'-deoxycytidine. Methylation of the NEP promoter was present in androgen-independent PC cell lines but not in androgen-dependent or small-cell derived PC cell lines and in 3 of 21 (14%) primary PCs from patients with androgen-dependent disease. Exposure of PC cells to the demethylating agent 5-aza-2'-deoxycytidine led to an increase in NEP transcripts in DU-145 and PC-3 cells. These data show that hypermethylation of the 5' CpG NEP island is associated with a loss of NEP expression in PC. Loss of NEP expression via hypermethylation of the NEP promoter may contribute to the development of neuropeptide-stimulated PCs.
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Lee Y, Lee WH, Lee SC, Ahn KJ, Choi YH, Park SW, Seo JD, Park JE. CD40L activation in circulating platelets in patients with acute coronary syndrome. Cardiology 2000; 92:11-6. [PMID: 10640791 DOI: 10.1159/000006940] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The CD40-CD40L interaction, which was initially shown to have important roles in the T cell-mediated activation of B cells during humoral immune responses, is now known to have roles in activation of endothelial cells, smooth muscle cells, and macrophages within atherosclerotic plaques. Recently, CD40L expression was found in activated platelets in the thrombus in vivo and CD40L was reported to be responsible for the platelet-mediated activation of endothelial cells in vitro. To investigate the activation status of platelets in coronary artery disease patients, we tested expression levels of CD40L, and platelet-endothelial cell adhesion molecule-1 (PECAM-1/CD31) in platelets isolated from peripheral blood, using flow cytometric analysis. Twenty-nine patients with acute coronary syndrome (10 acute myocardial infarction and 19 unstable angina patients) were compared with 14 normal subjects or 14 stable angina patients. In platelets isolated from normal subjects, the expression of CD40L was not detected in all subjects. In the patients with acute coronary syndrome, the average level of CD40L showed a significant increase (p = 0.0028), while stable angina patients did not have any increase when compared to normal subjects. Patients with more complex lesions or vessel occlusion tended to have a high platelet CD40L level compared to patients who do not. The expression levels of CD31 were increased in a small portion of the ACS patients. These data indicate that the rupture of plaque and subsequent formation of thrombus may lead to the activation of CD40L expression in circulating platelets of ACS patients.
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Lu JJ, Wu JC, Chiueh TS, Perng CL, Chi WM, Lee WH. Characterization of a highly glycopeptide-resistant Enterococcus gallinarum isolate. J Formos Med Assoc 2000; 99:305-10. [PMID: 10870314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND AND PURPOSE Adequate treatment of emergency infection involving antibiotic-resistant bacteria such as vancomycin-resistant Enterococcus requires a convergence of clinical and bacteriologic techniques. An isolate of Enterococcus gallinarum, designated as TSGH63, is known to be uncommonly vancomycin-resistant. This study investigated the genetic determinant for this unique characteristic. METHODS After completing the conventional identification and sensitivity tests, the genomic content of E. gallinarum TSGH63 was extracted and analyzed by pulse-field electrophoresis. A set of specific primers for vanA, vanB, vanC1, and vanC2/C3 genes was then applied in a multiplex polymerase chain reaction (PCR) to differentiate its genetic content. To locate the determinant for high vancomycin resistance, the electrophoresis profile was further analyzed by Southern blot using the digoxigenin (DIG)-labeled vanA gene probe. Finally, interspecies transfer of the vancomycin-resistance determinant of E. gallinarum TSGH63 was tested by a conjugation experiment in vitro. RESULTS A 50-kb plasmid was identified in the analysis of the genomic extract of E. gallinarum TSGH63 by pulse field electrophoresis. Using multiplex PCR, we demonstrated that E. gallinarum TSGH63 harbors a vanA gene in addition to a vanC1 gene. The DIG-labeled vanA gene-specific probe bound to the plasmid exclusively on the Southern blot. The plasmid-carried vanA gene, but not the vanC1 gene, was found to be transferable from TSGH63 to E. faecalis JH2-2 by conjugation in vitro. CONCLUSIONS This is the first report of isolation of E. gallinarum with a high level of resistance to glycopeptides in Taiwan. The demonstrated interspecies transfer of the vancomycin-resistance gene highlights the importance of stringent control of the use of vancomycin.
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Choi YJ, Lee WH, Rha KH, Xin ZC, Choi YD, Choi HK. Masturbation and its relationship to sexual activities of young males in Korean military service. Yonsei Med J 2000; 41:205-8. [PMID: 10817020 DOI: 10.3349/ymj.2000.41.2.205] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
This study examined the masturbatory experiences and other sexual activities of young Korean males in military service. The actual status of masturbation and its relationship to sexual activity questionnaire. A total of 1,212 young males among military personnel in Korea were interviewed with sexuality questionnaires on masturbation, sexual intercourse and personal characteristics. We divided these subjects into four groups according to the age of initiation of masturbation and analyzed the relationship between masturbation and other sexual activities. The mean age of subjects was 22.03 +/- 1.22 (19-27) years. The percentage of men who reported ever having masturbated was 98.1% (1189/1212) and the average age of initiation of masturbation was 14.26 +/- 1.66 years. So we divided 1,212 males into four groups on the basis of the average age below and above one standard deviation. Overall, 67.7% (821/1212) had experienced sexual intercourse, and significantly, the earlier the initiation age of masturbation, the higher the coitus rate in each group (p < 0.05). About 21.5% of the men who were not virgins had experienced their first sexual intercourse with prostitutes. The mean age of first coitus, the incidence of sexually transmitted disease (STD) and the frequency of masturbation were closely linked to the initiation age of masturbation, respectively (p < 0.05). A masturbatory guilt feeling was seen in about 10.9% (132/1212) and there was no significant difference according to the types of religious worship (p = 0.227). On the basis of this study, sexual activities generally increased accordingly as the beginning of masturbation was earlier. Coital incidence in this study was 67.7% for young males in Korean military service, and 21.5% of them had their first sexual intercourse with prostitutes. Prostitution still plays an important role in the sexual lives of males in Korea. The incidence of STD was over 10% and homosexual manifestation was seen in 1.07% of subjects. Thus a proper and sound sex education at school during childhood is needed in Korea. A large scale survey of sexual behavior in various populations is essential for the improvement of correct sexual concepts.
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Kim SC, Ahn TY, Choi HK, Choi NG, Chung TG, Chung WS, Hwang TK, Hyun JS, Jung GW, Kim CI, Kim JJ, Kim SW, Lee CH, Lee KS, Lee WH, Min KS, Moon KH, Paic JS, Park KS, Park NC, Park YK, Seo JK, Seo KK, Shin JS, Yoon YR, Lee WC. Multicenter study of the treatment of erectile dysfunction with transurethral alprostadil (MUSE) in Korea. Int J Impot Res 2000; 12:97-101. [PMID: 11052635 DOI: 10.1038/sj.ijir.3900490] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A Korean multicenter study was conducted to assess the effectiveness of transurethral alprostadil with MUSE in 334 subjects with chronic erectile dysfunction (ED) who were enrolled in 21 clinical centers. Patients with psychogenic impotence comprised about 30% of subjects. Intraurethral alprostadil was titrated in a stepwise fashion in the clinics from 250 to 500 or 1000 mcg based on erectile response and tolerability. The erectile responses were evaluated using an erection assessment scale (score of 1-5). The dose that produced a maximal penile response of score 5 (full rigid erection) or 4 (full tumescence, partial rigidity) was selected for home treatment. Patients who showed partial erection (score of 3) with 1000 mcg were also included in the home-treatment group. In-clinic phase: 198 men (59.3%) had maximal penile responses of score 4 or 5. The rate of maximal responses was not related to patient age, etiology or duration of the ED. A total of 228 (68.3%) men progressed to home treatment. The overall level of comfort of the transurethral alprostadil was rated as uncomfortable or very uncomfortable in 12%. Home phase: During the two-month period of home treatment, 178 (78.1%) men had successful sexual intercourse at least once, and 78.2% of administrations (1976) resulted in successful intercourse. The main causes of drop-out were insufficient erectile response in 27 men (11.8%), adverse reactions (mostly penile or urethral pain) in 7 (3.1%) or both in 7 (3.1%). In conclusion, transurethral alprostadil could be a suitable treatment option for patients with ED regardless of age and etiology of ED. Efficacy in an Asian population (Korea) is comparable to that reported previously in Caucasians.
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Nikitin AY, Riley DJ, Lee WH. A paradigm for cancer treatment using the retinoblastoma gene in a mouse model. Ann N Y Acad Sci 2000; 886:12-22. [PMID: 10667199 DOI: 10.1111/j.1749-6632.1999.tb09396.x] [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: 11/27/2022]
Abstract
Discovery of tumor suppressor genes has provided a rational approach to cancer prevention and treatment. Loss of retinoblastoma susceptibility gene (Rb) function is a rate-limiting event in the development of human and mouse cancers. Establishment of animal models of cancer associated with Rb deficiency allowed us to develop and test long-awaited approaches to genetic correction for treating tumors in vivo. Recent studies demonstrated that (1) prevention of carcinogenesis is achieved by correction of gene copy number in Rb+/- mice, and (2) reconstitution of Rb gene functions is sufficient for suppression of neoplasia in immunocompetent mice. These results fulfill a promise of cancer treatment by reconstitution of tumor suppressor function.
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Choi HK, Jung GW, Moon KH, Xin ZC, Choi YD, Lee WH, Rha KH, Choi YJ, Kim DK. Clinical study of SS-cream in patients with lifelong premature ejaculation. Urology 2000; 55:257-61. [PMID: 10688090 DOI: 10.1016/s0090-4295(99)00415-x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVES To investigate the clinical efficacy of SS-cream, the topical agent made from the extracts of nine natural products for the treatment of premature ejaculation, we performed a double-blind, randomized, placebo-controlled Phase III clinical study of patients with lifelong premature ejaculation in three medical centers. METHODS One hundred six patients (mean age 38.7 +/- 0.61 years) completed this study. The ejaculatory latency measured by stopwatch and sexual satisfaction ratio of both partner and patient were investigated twice in the screening period and once after each treatment (1 placebo 0.20 g and 5 SS-cream 0.20 g for a total of six treatments). Patients were instructed to apply the cream on the glans penis 1 hour before sexual intercourse in a double-blind randomized fashion. Clinical efficacy was compared with the prolongation of ejaculatory latency and improvement of the sexual satisfaction ratio before and after each treatment. RESULTS In the screening period, the mean ejaculatory latency was assessed at 1.37 +/- 0.12 minutes, and neither the patients nor their partners were satisfied with their sexual lives. After treatment, the mean ejaculatory latency was prolonged to 2.45 +/- 0.29 minutes in the placebo group and 10.92 +/- 0.95 minutes in the SS-cream group. The clinical efficacy of placebo and SS-cream as judged by an ejaculatory latency time prolonged more than 2 minutes was 15.09% and 79.81%, respectively. The improvement of sexual satisfaction to a grade higher than effective was 19.81% and 82.19%, respectively, for placebo and SS-cream. Of 530 trials of SS-cream, 98 (18.49%) resulted in a sense of mild local burning and mild pain. No adverse effect on sexual function or partner and no systemic side effects were observed. CONCLUSIONS According to these results, SS-cream is effective and safe in the treatment of premature ejaculation, with mild local side effects.
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Lu JJ, Ben RJ, Perng CL, Chi WM, Chu ML, Lee WH. Characterization of the first clinical isolate of vancomycin-resistant Enterococcus faecalis, AH803, in Taiwan. J Formos Med Assoc 2000; 99:178-81. [PMID: 10770036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
We previously isolated a vancomycin-resistant strain of Enterococcus faecalis, designated AH803, from the sputum of a patient with pneumonia and bacteremia in Taiwan. AH803 was resistant to vancomycin (minimal inhibitory concentration, MIC = 512 micrograms/mL) but susceptible to teicoplanin (MIC = 8 micrograms/mL), and harbored the vanA gene but not the vanB gene. In this study, we further characterized E. faecalis AH803 and the plasmid it was found to contain. DNA from AH803 was analyzed for the presence of vanA and vanB resistance genes by polymerase chain reaction. The vancomycin resistant phenotype was transferable from AH803 to E. faecalis JH2-2, at a frequency of 4.8 x 10(-2). AH803 was also resistant to gentamicin and chloramphenicol, and these antibiotic resistance phenotypes cotransferred with vancomycin resistance. The genes responsible for resistance to all three antibiotics were located on a 42-kb conjugative plasmid (pBL101). This plasmid had the same restriction enzyme digestion patterns as Tn1546, found in pIP816 of E. faecalis BM4147. Epidemiologic studies of glycopeptide resistance should perhaps combine phenotypic and genotypic methods, rather than using phenotypic methods alone.
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Choi YH, Lee WH, Park KY, Zhang L. p53-independent induction of p21 (WAF1/CIP1), reduction of cyclin B1 and G2/M arrest by the isoflavone genistein in human prostate carcinoma cells. Jpn J Cancer Res 2000; 91:164-73. [PMID: 10761703 PMCID: PMC5926325 DOI: 10.1111/j.1349-7006.2000.tb00928.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Genistein, a natural isoflavonoid phytoestrogen, is a strong inhibitor of protein tyrosine kinase and DNA topoisomerase II activities. Genistein has been shown to have anticancer proliferation, differentiation and chemopreventive effects. In the present study, we have addressed the mechanism of action by which genistein suppressed the proliferation of p53-null human prostate carcinoma cells. Genistein significantly inhibited the cell growth, which effect was reversible, and induced dendrite-like structure. The inhibitory effects of genistein on cell growth proliferation were associated with a G2/M arrest in cell cycle progression concomitant with a marked inhibition of cyclin B1 and an induction of Cdk inhibitor p21 (WAF1/CIP1) in a p53-independent manner. Following genistein treatment of cells, an increased binding of p21 with Cdk2 and Cdc2 paralleled a significant decrease in Cdc2 and Cdk2 kinase activity with no change in Cdk2 and Cdc2 expression. Genistein also induced the activation of a p21 promoter reporter construct, utilizing a sequence distinct from the p53-binding site. Analysis of deletion constructs of the p21 promoter indicated that the response to genistein could be localized to the 300 base pairs proximal to the transcription start site. These data suggest that genistein may exert a strong anticarcinogenic effect, and that this effect possibly involves an induction of p21, which inhibits the threshold kinase activities of Cdks and associated cyclins, leading to a G2/M arrest in the cell cycle progression.
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Xin ZC, Choi YD, Lee WH, Choi YJ, Yang WJ, Choi HK, Kim DK. Penile vibratory threshold changes with various doses of SS-cream in patients with primary premature ejaculation. Yonsei Med J 2000; 41:29-33. [PMID: 10731916 DOI: 10.3349/ymj.2000.41.1.29] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
SS-cream made with extracts from natural products is a topical agent for treating premature ejaculation (PE). In order to elucidate the penile vibratory threshold changes and clinical effects of various doses of SS-cream, 53 patients with primary PE were investigated in a double-blind randomized placebo-controlled study. The mean age was 37.3 +/- 6.4 years and mean ejaculatory latency was 1.37 +/- 0.52 minutes. Neither the patients nor their sexual partners were satisfied with their sexual lives. Vibratory threshold at the glans penis, penile shaft, scrotum and index finger were measured using a biothesiometer twice during the screening period and three times one hour after the application of respective creams (SS-cream 0.05, 0.10. 0.15, 0.20 gm and placebo 0.10 gm) on the glans penis according to the order of the allocation table in a randomized fashion. The efficacy of SS-cream was defined as when the vibration threshold increased by more than 4 microns compared to the value tested during the screening period. The vibratory thresholds at the glans penis increased significantly in a dose-dependent manner after the application of various doses (0.05, 0.10, 0.15, 0.20 gm) of SS-cream (p < 0.001), and the efficacy of SS-cream on the penile vibration threshold increased according to the increased dosage (penile shaft: 48.4, 51.6, 54.8, 64.5%, glans penis: 58.1, 67.7, 77.4, 83.9%, respectively). With these results, we concluded that SS-cream increased the penile sensory threshold dose dependently, and therefore it is clinically effective for treating the heightened penile sensory response in patients with PE.
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Park JE, Lee WH, Hwang TH, Chu JA, Kim S, Choi YH, Kim JS, Kim DK, Lee SH, Hong KP, Seo JD, Lee WR. Aging affects the association between endothelial nitric oxide synthase gene polymorphism and acute myocardial infarction in the Korean male population. Korean J Intern Med 2000; 15:65-70. [PMID: 10714094 PMCID: PMC4531736 DOI: 10.3904/kjim.2000.15.1.65] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES The aging process affects responsiveness and other functions of endothelium and vascular smooth muscle cells, predisposing the old vessels to the development of atherosclerotic lesions. Endothelial nitric oxide synthase (ecNOS) gene polymorphisms were shown to affect the occurrence of acute myocardial infarction (AMI). We hypothesized that aging may affect the association between the ecNOS gene polymorphism and AMI. METHODS We investigated the age-related distribution of the ecNOS gene a/b polymorphism in 121 male AMI patients and 206 age-matched healthy male controls. RESULTS The aa, ab and bb genotypes were found in 1, 49 and 156 cases among the control subjects and 5, 23 and 93 cases among the AMI patients, respectively. There was a significant correlation between the ecNOS polymorphism and AMI (p = 0.045). When the correlation was analyzed by age, the significance remained only in the group below the age of 51 (p = 0.009). The proportion of smokers was increased in the young patients when compared to the old patients (p = 0.033), indicating that smoking also has greater effect on the younger population. The incidences of hypertension and diabetes mellitus, however, were similar in both populations. CONCLUSION Our work provides the first evidence that links ecNOS polymorphism to the risk of AMI in relation to age. Young persons who smoke or have ecNOSaa genotype may have an increased risk of developing AMI. The functional as well as structural changes associated with aging in the vascular endothelium may mask the effect of the ecNOS polymorphism in the development of AMI in old persons.
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Juan CJ, Huang GS, Hsueh CJ, Lee WH, Hsu HH, Shen HJ, Chin SC, Hsiao HS. Primary hemangiopericytoma of the tibia: MR and angiographic correlation. Skeletal Radiol 2000; 29:49-53. [PMID: 10663590 DOI: 10.1007/s002560050009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The Magnetic Resonance Imaging (MRI) appearances of primary osseous hemangiopericytoma (HPC) have been rarely described. We report on a 46-year-old Chinese man with primary osseous HPC of the right tibia. The characteristic vascular distribution of this tumor, presenting with a "spoke-wheel" appearance on MR images and with angiographic correlation, is described. Although not pathognomonic, this MR appearance may be an important finding in suggesting the diagnosis of osseous HPC.
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Abstract
BRCA1 was the first breast cancer susceptibility gene to be identified and cloned. In individuals from high-risk families, mutations in BRCA1 increase the lifetime risk of developing breast cancer eight to tenfold, compared to the general population. How the BRCA1 protein product normally functions to suppress tumor formation and how defects in the gene can ultimately lead to breast cancer have been the focus of intense scrutiny by the scientific and medical communities. BRCA1 has intrinsic transactivation activity and is able to activate the p21 promoter. In addition, BRCA1 is linked to a number of genes involved in transcriptional regulation, including CtIP, c-Myc, the RNA holoenzyme complex, and the histone deacetylase complex. Moreover, BRCA1 is essential for cellular response to DNA damage repair. Inactivation of Brca1 in mouse embryonic stem and fibroblast cells results in increased cell sensitivity to DNA-damaging agents. In human cells, BRCA1 binds to both Rad50 and Rad51 and colocalizes with these proteins at repair foci. Part of BRCA1's response to DNA damage may in fact be corroborated through transcriptional regulation. The expression of GADD45, a DNA damage-responsive gene, is increased immediately after induction of BRCA1. Recently, BRCA1 was shown to repress estradiol (E2)-responsive ER-alpha-mediated transcriptional activity, potentially linking the multiple functions of BRCA1 to specific tissue targets. These recent developments in BRCA1 function are an encouraging step toward understanding the role of BRCA1 in breast cancer formation.
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Chen CF, Chen PL, Zhong Q, Sharp ZD, Lee WH. Expression of BRC repeats in breast cancer cells disrupts the BRCA2-Rad51 complex and leads to radiation hypersensitivity and loss of G(2)/M checkpoint control. J Biol Chem 1999; 274:32931-5. [PMID: 10551859 DOI: 10.1074/jbc.274.46.32931] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BRCA2 is a breast tumor suppressor with a potential function in the cellular response to DNA damage. BRCA2 binds to Rad51 through its BRC repeats. In support of the biological significance of this interaction, we found that the complex of BRCA2 and Rad51 in breast cancer MCF-7 cells was diminished upon conditional expression of a wild-type, but not a mutated, BRC4 repeat using the tetracycline-inducible system. Cells expressing a wild-type BRC4 repeat showed hypersensitivity to gamma-irradiation, an inability to form Rad51 radiation-induced foci, and a failure of radiation-induced G(2)/M, but not G(1)/S, checkpoint control. These results strongly suggest that the interaction between BRCA2 and Rad51 mediated by BRC repeats is critical for the cellular response to DNA damage.
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Utomo AR, Nikitin AY, Lee WH. Temporal, spatial, and cell type-specific control of Cre-mediated DNA recombination in transgenic mice. Nat Biotechnol 1999; 17:1091-6. [PMID: 10545915 DOI: 10.1038/15073] [Citation(s) in RCA: 152] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We have developed a universal system for temporal, spatial, and cell type-specific control of gene expression in mice that (1) integrates the advantages of tetracycline-controlled gene expression and Cre-recombinase-loxP site-mediated gene inactivation, and (2) simplifies schemes of animal crosses by combination of two control elements in a single transgene. Two transgenic strains were generated in which the cell type-specific control was provided by either the retinoblastoma gene promoter or the whey acidic protein promoter. Both promoters drive the expression of the reverse tetracycline-controlled transactivator (rtTA). Placed in cis configuration to the rtTA transcription unit, the rtTA-inducible promoter directs expression of Cre recombinase. In both strains crossed with cActXstopXLacZ reporter mice, which have a loxP-stop of transcription/translation-loxP-LacZ cassette driven by chicken beta-actin promoter, Cre-loxP-mediated DNA recombination leading to LacZ expression was accurately regulated in a temporal, spatial, and cell type-specific manner. This approach can be applied to establishment of analogous mouse strains with virtually any promoter as systems to control gene regulation in a variety of cell types.
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Choi HK, Xin ZC, Choi YD, Lee WH, Mah SY, Kim DK. Safety and efficacy study with various doses of SS-cream in patients with premature ejaculation in a double-blind, randomized, placebo controlled clinical study. Int J Impot Res 1999; 11:261-4. [PMID: 10553804 DOI: 10.1038/sj.ijir.3900431] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVES SS-cream is a topical agent made from the extracts of natural products for treating premature ejaculation (PE). To determine the optimal clinical dosage of SS-cream on PE, we investigated the safety and efficacy of SS-cream with various doses. A double blind, randomized placebo controlled clinical study was performed. METHODS Fifty patients completed the study. Mean age of the patients was 37.1+/-1.O y and mean ejaculatory latency was 1.35+/-0.07 min. Sexual satisfaction rate of both the partner and patient was 16.2%. Each patient was instructed to apply the different cream (placebo, SS-cream 0.05, 0.10, 0.15, 0.20 g) on glans penis 1 h before sexual intercourse in random fashion. The ejaculatory latency was measured by stop watch and the satisfaction rate of both partner and patient was also recorded two times in the screening period and after the application of each test drugs. Clinical efficacy was considered if ejaculatory latency was prolonged more than 2 min and sexual satisfaction rate increased more than 20% than that of pretest values. RESULTS The mean ejaculatory latencies were significantly prolonged after using various test drugs (placebo 2.27+/-0.32, SS-cream 0.05 g 4.47+/-0.81, 0.10 g 5.34+/-0.79, 0.15 g 6.22+/-0.87, 0.20 g 11.06+/-1.17 min, respectively). Clinical efficacies evaluated by ejaculatory latency were placebo 18%, SS-cream 0.05 g 30%, 0.10 g 60%, 0.15 g 54%, 0.20 g 84%, respectively. The satisfaction rate was also significantly increased dose-dependently (placebo 26%, SS-cream 0.05 g 60%, 0.10 g 70%, 0.15 g 78%, 0.20 g 90%, respectively). A side effect such as local mild burning sensation was noted in 35/250 times (14%) and no adverse effect on sexual function and no systemic side effects were observed. From the result of logistic regression analysis on clinical efficacy, the ED50 of SS-cream was obtained as 0.10 g. SS-cream 0.20 g was effective in 84% without any serious systemic side effects. CONCLUSION From the above results, our conclusions are that SS-cream is effective on the treatment of PE with a few local side effects and that clinical optimal dose of SS-cream is 0.20 g.
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Lee WH, Wang GM, Yang XL, Seaman LB, Vannucci SI. Perinatal hypoxia-ischemia decreased neuronal but increased cerebral vascular endothelial IGFBP3 expression. Endocrine 1999; 11:181-8. [PMID: 10709766 DOI: 10.1385/endo:11:2:181] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/1999] [Revised: 07/30/1999] [Accepted: 07/30/1999] [Indexed: 11/11/2022]
Abstract
In adults, insulin-like growth factor binding protein 3 (IGFBP3) is the main carrier protein for circulating insulin-like growth factors (IGFs) (IGF-I and -II). While most IGFBP3 is synthesized in the liver, it is also expressed locally by many cell types including vascular endothelial cells. The regulation of this endothelial IGFBP3 expression, especially in response to hypoxic-ischemic injury, has not been investigated in vivo. Using in situ hybridization histochemistry, we studied the cellular distribution of IGFBP3 mRNA in rat brains following hypoxic-ischemic injury at 1, 5, 24, and 72 h of recovery. In normal P7 rat brain, IGFBP3 mRNA was found in neurons within the thalamus, hippocampus, and amygdaloid. Low levels of IGFBP3 mRNA were also detected in cerebral vascular endothelial cells. After the hypoxic-ischemic injury, the levels of neuronal IGFBP3 mRNA substantially decreased within 24 h in areas that were normally supplied by the middle cerebral artery. In the meantime, there was an immediate increase in IGFBP3 expression in vascular endothelial cells throughout the affected hemisphere. This vascular IGFBP3 expression was further enhanced with the highest level at 24 h of recovery whereas neuronal IGFBP3 expression was further decreased. By 72 h of recovery, IGFBP3 was no longer expressed in vascular endothelial cells. Taken together, the activation of IGFBP3 is a likely mechanism by which vascular endothelial cells respond to hypoxic-ischemic insult. In addition, increased endothelial IGFBP3 may modulate the interaction of IGFs with IGF-I receptors at the site of injury and/or act independently on endothelial cell growth.
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Lee WH, Lee Y, Kim JR, Chu JA, Lee SY, Jung JO, Kim JS, Kim S, Seo JD, Rhee SS, Park JE. Activation of monocytes, T-lymphocytes and plasma inflammatory markers in angina patients. Exp Mol Med 1999; 31:159-64. [PMID: 10551265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Inflammation and activation of immune cells have important roles in the pathogenesis of atherosclerosis. We analyzed the plasma levels of inflammatory markers and the degree of activation of peripheral blood monocytes and T-lymphocytes isolated from 12 unstable angina, 12 stable angina, and 12 normal subjects. In 20%-33% of patients, monocytes expressed high basal levels of IL-8, tissue factor, IL-1beta, and monocyte chemoattractant protein-1 mRNA. Furthermore, basal mRNA levels of these cytokines showed strong correlation with each other (p < 0.01 in all combination) but not with tumor necrosis factor-alpha or transforming growth factor-beta1. Plasma level of C-reactive protein was highest in the unstable angina patients (1.63+/-0.70 mg/l) and lowest in the control subjects (0.22+/-0.08 mg/l) (P = 0.03). We also observed a high correlation between C-reactive protein level and the occurrence of minor and major coronary events during 6 months of follow-up. Activation status of T-cells, assessed by the percentage of HLA-DR positive cells, was highest in the unstable angina patients (26.8+/-1.4%) compared with that in the control (14.7+/-1.2%) (P = 0.0053). Our data represent the first case showing that the circulating monocytes in angina patients are activated to a state express numerous proatherogenic cytokines. These results may help to diagnose angina patients according to the inflammatory markers and evaluate the prognosis of the disease.
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Liechty EA, Boyle DW, Moorehead H, Lee WH, Yang XL, Denne SC. Glucose and amino acid kinetic response to graded infusion of rhIGF-I in the late gestation ovine fetus. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 277:E537-43. [PMID: 10484367 DOI: 10.1152/ajpendo.1999.277.3.e537] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Insulin-like growth factor I (IGF-I) has anabolic effects and is thought to be important in fetal development. The present study was designed to determine the dose response of recombinant human (rh) IGF-I on ovine fetal glucose and amino acid kinetics. Chronically catheterized fetal lambs were studied at 122-127 days gestation. The kinetics of leucine, phenylalanine, and glucose were measured before and during the infusion of rhIGF-I. rhIGF-I was infused into the fetal inferior vena cava at low, medium, or high rates (9.9, 20.1, or 40.2 nmol/h, respectively). A stepwise increase in serum IGF-I was achieved (164 +/- 3, 222 +/- 7, and 275 +/- 5 ng/ml). Insulin concentrations were decreased at the medium and high rhIGF doses. The rate of appearance (Ra) of leucine and phenylalanine and leucine oxidation decreased. Phenylalanine appearance from protein breakdown was decreased, with a maximal suppression of 30% observed at the highest rate of infusion. Glucose Ra was increased at the medium and high doses; other aspects of glucose metabolism were unchanged. The change in both glucose Ra and suppression of proteolysis was significantly correlated to the rhIGF-I infusion rate. It is concluded that rhIGF-I exerts dose-related effects in the ovine fetus, increasing fetoplacental glucose turnover and causing significant suppression of both proteolysis and amino acid oxidation.
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Kang JC, Jao SW, Lee WH, Chao PC. Lymphatic cyst of the colon: a case report. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:560-3. [PMID: 10462835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
A rare case of a lymphatic cyst of the ascending colon is reported. The lobulated and fluctuant lesion, located in the hepatic flexure, was diagnosed by barium enema and colonoscopy, incidentally. Surgical treatment with segmental resection of the ascending colon was done because of the risk of obstruction and the question of an underlying malignancy. The clinical features, appropriate treatment, preoperative diagnosis and histopathology are discussed. We emphasize that lymphatic cysts are very rare and are difficult to identify by radiology or colonoscopy before surgery. They must be included in the differential diagnosis of submucosal tumors such as lipomas, leiomyomas and hemangiomas.
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138
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Zheng L, Chen Y, Lee WH. Hec1p, an evolutionarily conserved coiled-coil protein, modulates chromosome segregation through interaction with SMC proteins. Mol Cell Biol 1999; 19:5417-28. [PMID: 10409732 PMCID: PMC84384 DOI: 10.1128/mcb.19.8.5417] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/1999] [Accepted: 05/05/1999] [Indexed: 11/20/2022] Open
Abstract
hsHec1p, a Homo sapiens coiled-coil-enriched protein, plays an important role in M-phase progression in mammalian cells. A Saccharomyces cerevisiae protein, identical to Tid3p/Ndc80p and here designated scHec1p, has similarities in structure and biological function to hsHec1p. Budding yeast cells deleted in the scHEC1/NDC80 allele are not viable, but this lethal phenotype can be rescued by hsHEC1 under control of the endogenous scHEC1 promoter. At the nonpermissive temperature, significant mitotic delay, chromosomal missegregation, and decreased viability were observed in yeast cells with temperature-sensitive (ts) alleles of hsHEC1. In the hshec1-113 ts mutant, we found a single-point mutation changing Trp395 to a stop codon, which resulted in the expression of a C-terminally truncated 45-kDa protein. The binding of this mutated protein, hshec1-113p, to five identified hsHec1p-associated proteins was unchanged, while its binding to human SMC1 protein and yeast Smc1p was ts. Hec1p also interacts with Smc2p, and the binding of the mutated hshec1-113p to Smc2p was not ts. Overexpression of either hsHEC1 or scHEC1 suppressed the lethal phenotype of smc1-2 and smc2-6 at nonpermissive temperatures, suggesting that the interactions between Hec1p and Smc1p and -2p are biologically significant. These results suggest that Hec1 proteins play a critical role in modulating chromosomal segregation, in part, through their interactions with SMC proteins.
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139
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Zhong Q, Chen CF, Li S, Chen Y, Wang CC, Xiao J, Chen PL, Sharp ZD, Lee WH. Association of BRCA1 with the hRad50-hMre11-p95 complex and the DNA damage response. Science 1999; 285:747-50. [PMID: 10426999 DOI: 10.1126/science.285.5428.747] [Citation(s) in RCA: 452] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
BRCA1 encodes a tumor suppressor that is mutated in familial breast and ovarian cancers. Here, it is shown that BRCA1 interacts in vitro and in vivo with hRad50, which forms a complex with hMre11 and p95/nibrin. Upon irradiation, BRCA1 was detected in discrete foci in the nucleus, which colocalize with hRad50. Formation of irradiation-induced foci positive for BRCA1, hRad50, hMre11, or p95 was dramatically reduced in HCC/1937 breast cancer cells carrying a homozygous mutation in BRCA1 but was restored by transfection of wild-type BRCA1. Ectopic expression of wild-type, but not mutated, BRCA1 in these cells rendered them less sensitive to the DNA damage agent, methyl methanesulfonate. These data suggest that BRCA1 is important for the cellular responses to DNA damage that are mediated by the hRad50-hMre11-p95 complex.
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Clawson TF, Vannucci SJ, Wang GM, Seaman LB, Yang XL, Lee WH. Hypoxia-ischemia-induced apoptotic cell death correlates with IGF-I mRNA decrease in neonatal rat brain. BIOLOGICAL SIGNALS AND RECEPTORS 1999; 8:281-93. [PMID: 10494014 DOI: 10.1159/000014599] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Hypoxia-ischemia induces apoptotic and necrotic cell death, which results partially from persistent alterations in cellular energy homeostasis. Insulin-like growth factor I (IGF-I) is an anabolic pleiotrophic factor required by developing neurons for their optimal proliferation, differentiation, and survival. To determine how cell death and changes in IGF-I gene expression relate to the extent of hypoxia-ischemia, we evaluated the time course of apoptosis in a neonatal hypoxia-ischemia model in relation to the cellular distribution of IGF-I and IGFBP5 mRNA. Severe hypoxia-ischemia results in an immediate decrease in neuronal IGF-I and IGFBP5 mRNA. The decrease in neuronal IGF-I mRNA was concurrent with an increase in the number of apoptotic cells. It is conceivable that the immediate decrease in IGF-I gene expression may contribute to the impending neuronal death and selective vulnerability of myelinogenesis during the perinatal period.
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141
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Baecker PA, Lee WH, Verity AN, Eglen RM, Johnson RM. Characterization of a promoter for the human glial cell line-derived neurotrophic factor gene. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1999; 69:209-22. [PMID: 10366742 DOI: 10.1016/s0169-328x(99)00106-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To address the regulation of glial cell line-derived neurotrophic factor (GDNF) gene expression, we have isolated 5' extended cDNAs, cloned the human GDNF gene, and characterized the promoter. GDNF-encoding 5' extended cDNAs containing a novel exon were isolated via reverse transcription-polymerase chain reaction (RT-PCR) of mRNA from human fetal kidney and adult skeletal muscle. The GDNF gene was isolated from a human genomic library in a P1 bacteriophage vector. Analysis of the 5' flanking sequence revealed a promoter that lacks a CCAAT-box motif and is GC rich. Consensus binding sites for a variety of transcription factors have been identified in the promoter. Promoter/reporter plasmids have been constructed by fusion of the promoter and a portion of exon I to a luciferase gene. The promoter/reporter construct and a number of promoter deletions were transiently transfected into two human cell lines known to express GDNF. Multiple enhancer and silencer regions were revealed as well as a minimal promoter sufficient for basal transcription. Finally, a RT-PCR assay, specific for transcripts originating from this GDNF promoter, was developed and used to show that this promoter is active in vivo. The results suggest GDNF is regulated in a complex manner.
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Lee WH, Toyama MH, Soares AM, Giglio JR, Marangoni S, Polikarpov I. Crystallization and preliminary X-ray diffraction studies of piratoxin III, a D-49 phospholipase A2 from the venom of Bothrops pirajai. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 1999; 55:1229-30. [PMID: 10329793 DOI: 10.1107/s0907444999004576] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Piratoxin III (PrTX-III) is a phospholipase A2 (PLA2, E.C. 3.1.1.4, phosphatide sn-2 acylhydrolase) isolated from Bothrops pirajai. Crystals of PrTX-III were obtained using the vapour-diffusion technique and X-ray diffraction data have been collected to 2.7 A resolution. The enzyme was crystallized in the space group C2 with unit-cell parameters a = 60.88, b = 100.75, c = 48.19 A, beta = 123. 89 degrees. A molecular-replacement solution of the structure has been found using bothropstoxin I from the venom of B. jararacussu as a search model.
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Li S, Chen PL, Subramanian T, Chinnadurai G, Tomlinson G, Osborne CK, Sharp ZD, Lee WH. Binding of CtIP to the BRCT repeats of BRCA1 involved in the transcription regulation of p21 is disrupted upon DNA damage. J Biol Chem 1999; 274:11334-8. [PMID: 10196224 DOI: 10.1074/jbc.274.16.11334] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in BRCA1 are responsible for nearly all of the hereditary ovarian and breast cancers, and about half of those in breast cancer-only kindreds. The ability of BRCA1 to transactivate the p21 promoter can be inactivated by mutation of the conserved BRCA1 C-terminal (BRCT) repeats. To explore the mechanisms of this BRCA1 function, the BRCT repeats were used as bait in a yeast two-hybrid screen. A known protein, CtIP, a co-repressor with CtBP, was found. CtIP interacts specifically with the BRCT repeats of BRCA1, both in vitro and in vivo, and tumor-derived mutations in this region abolished these interactions. The association of BRCA1 with CtIP was also abrogated in cells treated with DNA-damaging agents including UV, gamma-irradiation, and adriamycin, a response correlated with BRCA1 phosphorylation. The transactivation of the p21 promoter by BRCA1 was diminished by expression of exogenous CtIP and CtBP. These results suggest that the binding of the BRCT repeats of BRCA1 to CtIP/CtBP is critical in mediating transcriptional regulation of p21 in response to DNA damage.
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Chen Y, Chen PL, Chen CF, Sharp ZD, Lee WH. Thyroid hormone, T3-dependent phosphorylation and translocation of Trip230 from the Golgi complex to the nucleus. Proc Natl Acad Sci U S A 1999; 96:4443-8. [PMID: 10200281 PMCID: PMC16351 DOI: 10.1073/pnas.96.8.4443] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Trip230 is a novel coactivator of the thyroid hormone receptor that is negatively regulated by the retinoblastoma tumor-suppressor protein. In an examination of its subcellular distribution, Trip230 localized predominantly to the vicinity of the Golgi instead of the nucleus, as other nuclear hormone receptor coactivators. Using a series of deletion mutants, a critical region identified for Golgi area targeting coincided with a previously defined thyroid hormone receptor-binding domain of Trip230. During cell cycle progression, the expression level of Trip230 is constant and a significant portion is imported into the nucleus at S phase. Within an hour of treating cells with T3, Trip230 immunofluorescence transiently colocalized with TR in prominent subnuclear structures. T3-dependent nuclear import of Trip230 does not require new protein synthesis. Coincident with T3 treatment and nuclear import, newly phosphorylated residue(s) appeared in Trip230, suggesting that phosphorylation may be involved in its nuclear import. These findings provided a novel mechanism for the regulation of nuclear hormone transcription factors by hormone-responsive phosphorylation and nuclear import of cytoplasmically located coactivators.
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Chang JL, Tsao YP, Liu DW, Han CP, Lee WH, Chen SL. The expression of type I growth factor receptors in the squamous neoplastic changes of uterine cervix. Gynecol Oncol 1999; 73:62-71. [PMID: 10094882 DOI: 10.1006/gyno.1998.5301] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
AIM The type I family of growth factor receptors includes ErbB1, ErbB2, ErbB3, and ErbB4 which are frequently overexpressed in various human cancer cells. In this study, we systematically investigated the frequency and distribution of these four receptors in relation to neoplastic changes and tumor behaviors in the uterine cervix. MATERIALS A total 84 of cases including 12 cases of normal cervical tissues, 6 cases of low grade squamous intraepithelial lesion, 10 cases of high grade squamous intraepithelial lesion, and 56 cases of squamous cells carcinoma were examined. RESULTS Our results show significant difference with increasing grades of dysplasia in terms of these four receptor expressions. No association was found between these four receptors and cell keratinization/differentiation of squamous cell carcinoma of the cervix. Of the four receptors studied, only the expression of erbB2/neu gene was significantly associated with lymph nodal metastasis. Moreover, we find that the coexpression of ErbB1 and ErbB4 was significant in cervical carcinoma. CONCLUSIONS The coexpression of ErbB1 and ErbB4 in cervical carcinoma suggests that they may be involved in receptor heterodimerization leading to the activation of signaling pathway in the cervical carcinoma.
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Nikitin AY, Juárez-Pérez MI, Li S, Huang L, Lee WH. RB-mediated suppression of spontaneous multiple neuroendocrine neoplasia and lung metastases in Rb+/- mice. Proc Natl Acad Sci U S A 1999; 96:3916-21. [PMID: 10097138 PMCID: PMC22395 DOI: 10.1073/pnas.96.7.3916] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Alterations in pathways mediated by retinoblastoma susceptibility gene (RB) product are among the most common in human cancer. Mice with a single copy of the Rb gene are shown to develop a syndrome of multiple neuroendocrine neoplasia. The earliest Rb-deficient atypical cells were identified in the intermediate and anterior lobes of the pituitary, the thyroid and parathyroid glands, and the adrenal medulla within the first 3 months of postnatal development. These cells form gross tumors with various degrees of malignancy by postnatal day 350. By age of 380 days, 84% of Rb+/- mice exhibited lung metastases from C-cell thyroid carcinomas. Expression of a human RB transgene in the Rb+/- mice suppressed carcinogenesis in all tissues studied. Of particular clinical relevance, the frequency of lung metastases also was reduced to 12% in Rb+/- mice by repeated i.v. administration of lipid-entrapped, polycation-condensed RB complementary DNA. Thus, in spite of long latency periods during which secondary alterations can accumulate, the initial loss of Rb function remains essential for tumor progression in multiple types of neuroendocrine cells. Restoration of RB function in humans may prove an effective general approach to the treatment of RB-deficient disseminated tumors.
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Abstract
A case of colonic atresia (CA) and aganglionosis is presented, which is probably the tenth in the English literature. The boy presented on day 3 of life with delayed passage of meconium, milk intolerance, and progressive abdominal distension. A barium enema study was complicated by barium peritonitis. Emergency peritoneal lavage was done and the intestinal obstruction was relieved by a proximal defunctioning ileostomy; type III CA (Grosfeld classification) was identified. The proximal atretic end was the blind-ending caecum and the distal atretic end commenced in the splenic area as a microcolon extending to the pelvis and replacing the normal colon. Total colonic aganglionosis (TCA) was confirmed by biopsies. This is the first case in the literature of TCA with CA documented before any attempts at colonic resection and anastomosis were made. This association highlights the recommendation for biopsy of the micro-colon and rectum when Type III CA (Grosfeld classification) is encountered in a newborn. The infant underwent a cholecystectomy and Duhamel-Martin operation at 14 months that was complicated by abdominal wound dehiscence; the ileostomy was closed at 22 months of age.
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Wong YK, Wu JJ, Hsu CC, Liao SY, Chung MT, Lee WH. Intracerebral hemorrhage caused by cerebral amyloid angiopathy: a case report. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1999; 62:55-60. [PMID: 10063714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Cerebral amyloid angiopathy (CAA) accounts for approximately 10% of spontaneous intracerebral hemorrhages (ICH), and typically occurs in the cortex and subcortical white matter. It is characterized by the deposition of amyloid fibrils in the leptomeningeal, cortical and subcortical arteries. Pathologically, amyloid is stained pink with Congo red and shows yellow-green birefringence when viewed under polarized light. Although there have been many reports of CAA in the literature, it has rarely been described in Taiwan. This is the report of a case of a 75-year-old man with ICH caused by CAA. The postoperative course was uneventful. The incidence of this disease increases with age. The authors, therefore, suggest conducting a brain biopsy and special stain for CAA in each operative case of spontaneous ICH, especially in the elderly.
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Hwang TH, Lee WH, Kimura A, Satoh M, Nakamura T, Kim MK, Choi SK, Park JE. Early expression of a malignant phenotype of familial hypertrophic cardiomyopathy associated with a Gly716Arg myosin heavy chain mutation in a Korean family. Am J Cardiol 1998; 82:1509-13. [PMID: 9874056 DOI: 10.1016/s0002-9149(98)00695-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The clinical course and prognosis of familial hypertrophic cardiomyopathy (HCM) are different according to the type of mutation in the genes for sarcomere proteins. It has been disputed that a mutation, which occurs at a functionally important region in the sarcomere proteins, may increase the penetrance and expressivity of the disease. We searched for a causative mutation in an HCM family, which is characterized by early expression of clinical phenotype, high incidence of sudden death at young ages, and progressive heart failure in adults. Among the 32 family members in 4 generations, 13 were affected; 4 died suddenly before age 16, 2 children have already had full expression of the cardiac hypertrophy, and other adults have either progressive heart failure or poor left ventricular systolic functions. PCR-SSCP (polymerase chain reaction-single strand confirmation polymorphism) analysis of genomic DNAs isolated from peripheral blood leukocytes of the family members identified a Gly716Arg mutation in the cardiac beta-myosin heavy chain gene, which was cosegregated with the clinical phenotype. The mutation is localized near a functionally important site of the myosin heavy chain, the 2 active thiols, which contribute to the adenosine triphosphatase activity of myosin S1. This family provides further evidence that the mutation, which occurs at a functionally important site of the myosin heavy chain, is associated with the high penetrance and early expression of HCM.
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Lee WH, Park YM, Kim JI, Park WY, Kim SH, Jang JJ, Seo JS. Expression of heat shock protein 70 blocks thymic differentiation of T cells in transgenic mice. Immunology 1998; 95:559-65. [PMID: 9893045 PMCID: PMC1364352 DOI: 10.1046/j.1365-2567.1998.00633.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Heat shock protein 70 (HSP70) is involved not only in protein folding, but also in processes of differentiation and cell-cycle progression. Recently, HSP70 has been implicated in mediation of functions of some immunosuppressive agents. To study the role of HSP70 in differentiation of haematopoietic cells, we generated transgenic mice using the human inducible hsp70 gene fused to the mouse H-2K promoter. These mice develop a T-cell deficiency that is characterized by thymic hypoplasia and a significant reduction in peripheral T cells. The total number of thymocytes is about 100-fold less than that in normal mice. The majority of the thymocytes are immature T cells that express neither CD4 nor CD8 molecules, indicating that T cells are affected at an early stage of thymic differentiation. Expression of the transgenic HSP70 was detected both in bone marrow cells and in thymocytes. Furthermore, injection of normal bone marrow cells into the T-cell deficient mice led to the generation of mature T cells indicating that the T-cell deficiency was caused by the action of HSP70 in T cells. The blockage of differentiation occurred only in T cells, both alphabeta- and gammadelta-T-cell receptor (TCR)-bearing cells, but not in B cells, granulocytes, and monocytes. The observations suggest that HSP70 may inhibit a cellular process that is essential for the differentiation of early stage T cells. Further experiments using this model system will widen our understanding of HSP70 and its function on a molecular level.
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