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Wei S, Gilvary DL, Corliss BC, Sebti S, Sun J, Straus DB, Leibson PJ, Trapani JA, Hamilton AD, Weber MJ, Djeu JY. Direct tumor lysis by NK cells uses a Ras-independent mitogen-activated protein kinase signal pathway. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:3811-9. [PMID: 11034387 DOI: 10.4049/jimmunol.165.7.3811] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Destruction of tumor cells is a key function of lymphocytes, but the molecular processes driving it are unclear. Analysis of signal molecules indicated that mitogen-activated protein kinase (MAPK)/extracellular regulated kinase 2 critically controlled lytic function in human NK cells. We now have evidence to indicate that target ligation triggers a Ras-independent MAPK pathway that is required for lysis of the ligated tumor cell. Target engagement caused NK cells to rapidly activate MAPK within 5 min, and PD098059 effectively blocked both MAPK activation and tumoricidal function in NK cells. Target engagement also rapidly activated Ras, detected as active Ras-GTP bound to GST-Raf-RBD, a GST fusion protein linked to the Raf protein fragment containing the Ras-GTP binding domain. However, Ras inactivation by pharmacological disruption with the farnesyl transferase inhibitor, FTI-277, had no adverse effect on the ability of NK cells to lyse tumor cells or to express MAPK activation upon target conjugation. Notably, MAPK inactivation with PD098059, but not Ras inactivation with FTI-277, could interfere with perforin and granzyme B polarization within NK cells toward the contacted target cell. Using vaccinia delivery of N17 Ras into NK cells, we demonstrated that IL-2 activated a Ras-dependent MAPK pathway, while target ligation used a Ras-independent MAPK pathway to trigger lysis in NK cells.
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227
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Wei S, Chow LT, Sanderson JE. Effect of carvedilol in comparison with metoprolol on myocardial collagen postinfarction. J Am Coll Cardiol 2000; 36:276-81. [PMID: 10898446 DOI: 10.1016/s0735-1097(00)00671-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES We sought to compare the effects of two different beta-blockers, carvedilol and metoprolol, to an angiotensin-converting enzyme (ACE) inhibitor (captopril) on myocardial collagen deposition during healing and ventricular remodeling after myocardial infarction (MI). BACKGROUND Beta-adrenergic blockade has been shown to be beneficial post-MI and in chronic heart failure. Carvedilol is a new-generation vasodilating beta-blocker with additional alpha1-adrenoceptor antagonism and an antiproliferative action, but it is not known if it is more beneficial than standard selective beta-blockers. METHODS Using a rat model of MI, induced by left coronary ligation, we studied the effects of 11 weeks of therapy with oral carvedilol, metoprolol or captopril on hemodynamics, tissue weights, collagen volume fraction and hydroxyproline content. RESULTS Both beta-blockers caused similar decreases in heart rate and LVEDP compared with untreated post-MI rats. At equivalent beta-adrenoceptor blocking doses, however, carvedilol, but not metoprolol, attenuated the increase in collagen content in noninfarcted regions and prevented the increase in right ventricular weight/body weight (all p < 0.05), and its effect was similar to captopril. Metoprolol treatment tended to increase right ventricular weight and heart weight (p < 0.05). There were no differences in infarct size between the groups. CONCLUSIONS Long-term treatment with both beta-blockers, as well as an ACE inhibitor, benefited the healing process in rats post-MI. At equivalent myocardial beta-adrenoceptor blocking doses, however, carvedilol significantly reduced myocardial collagen in the noninfarcted myocardium and cardiac hypertrophy in the right ventricle, whereas metoprolol had no effect on myocardial collagen deposition.
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Abstract
The nucleotide sequence of Hepatitis E virus (HEV) serous isolates (G-9 and G-20) from Guangzhou, South China, which has been reported previously, are divergent significantly from those of other reported HEV isolates. In order to investigate more extensively the Guangzhou isolate, the 93G strain was isolated from the faecal sample of the same individual as G-9 by A549 cell culture and identified immunologically and by molecular biological techniques. The results showed that strain 93G could be propagated in an A549 cell line causing cytopathic effects. The viral particles were aggregated by a specific antibody to HEV Chinese Xinjiang strain (87A) observed using immunoelectron microscopy and were similar morphologically to HEV from other sources. In this study, an indirect fluorescent antibody assay was first developed to examine HEV antigen in the infected cells, by immunofluorescence in the cytoplasm and on the surface membrane of the cells. The 58-kDa and 82-kDa native structural proteins of HEV were also identified in this study by Western blotting. The 93G genome showed high homology (93%) with G-9 previously reported but was also as divergent from the Burmese, Mexican, Chinese Xinjiang isolates and the recently reported US-1 isolate, as was G-9. The data presented indicate that 93G propagated in A549 cells, together with its related serum isolate G-9, represents another HEV strain circulating in China and is responsible for some sporadic hepatitis E infections.
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229
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Liu JH, Wei S, Lamy T, Epling-Burnette PK, Starkebaum G, Djeu JY, Loughran TP. Chronic neutropenia mediated by fas ligand. Blood 2000; 95:3219-22. [PMID: 10807792] [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
Chronic neutropenia, often associated with rheumatoid arthritis, is a characteristic finding in large granular lymphocyte (LGL) leukemia. The mechanism of neutropenia is not known. Normal neutrophil survival is regulated by the Fas-Fas ligand apoptotic system. We hypothesized that neutropenia in LGL leukemia is mediated by dysregulated expression of Fas ligand. Levels of Fas ligand in serum samples from patients with LGL leukemia were measured with a Fas ligand enzyme-linked immunosorbent assay. The effects of serum from patients with LGL leukemia on apoptosis of normal neutrophils were determined by flow cytometry and morphologic assessment. High levels of circulating Fas ligand were detected in 39 of 44 serum samples from patients with LGL leukemia. In contrast, Fas ligand was undetectable in 10 samples from healthy donors. Serum from the patients triggered apoptosis of normal neutrophils that depended partly on the Fas pathway. Resolution of neutropenia was associated with disappearance or marked reduction in Fas ligand levels in 10 of 11 treated patients. These data suggest that high levels of Fas ligand are a pathogenetic mechanism in human disease. (Blood. 2000;95:3219-3222)
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230
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Zhang D, Jin S, Wei S, Wang X, Sun B. [Troponin T during cardiopulmonary bypass]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2000; 38:372-4. [PMID: 11832062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To evaluate the effect of cardiopulmonary bypass (CPB) on myocardial troponin T and its clinical significance and relationship to myocardial cell injury. METHODS Thirty-seven patients underwent open heart surgery under CPB. The procedures included correction of congenital heart disease in 15 patients, valve replacement in 15, and coronary artery bypass grafting in 7. Blood samples were taken at four different time intervals for assessing a troponin T. Correlative factors including duration of clamping of aorta, dosage of cardioplegic solution, and metabolic acidosis were studied. RESULTS When clamping time > 60 minutes, dosage of cardioplegia solution < 10 ml/kg and existing metabolic acidosis, the level of troponin T was significantly increased (P < 0.01). CONCLUSION The elevation of troponin T is closely related to cardiopulmonary bypass, especially the duration of clamping of aorta, insufficiency of cardioplegia, and metabolic acidosis.
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231
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Fu Y, Wei S, Lin H, Zhang Y. [Effects of tea polyphenols on cell kinetics and apoptosis of primary cultured rat skin keratinocytes]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 2000; 29:94-6. [PMID: 12725085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
In order to study the effects of tea polyphenols on cell growth and apoptosis of primary cultured rat skin keratinocytes, the safe dosage of tea polyphenols was determined by the release of lactate dehydrogenase(LDH). Cell counting(cytometry) and flow cytometry(FCM) were used to estimate the cell growth and the percentages of cells in different cell cycle phases or apoptosis. The results showed that tea polyphenols stimulated the cell growth from G1/G0 to G2/M phase, enhanced the synthesis of DNA(increase S phase) and increased the proliferative index(PI) from 18.17% to 25.62%. Also, it could block the occurrence of apoptosis. It is concluded that tea polyphenols could stimulate the growth of skin keratinocytes through stimulating the synthesis of cell DNA and inhibiting apoptosis.
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232
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Wei S, Xu T, Ashery U, Kollewe A, Matti U, Antonin W, Rettig J, Neher E. Exocytotic mechanism studied by truncated and zero layer mutants of the C-terminus of SNAP-25. EMBO J 2000; 19:1279-89. [PMID: 10716928 PMCID: PMC305669 DOI: 10.1093/emboj/19.6.1279] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The highly conserved SNARE proteins, SNAP-25, syntaxin and synaptobrevin, form a tight ternary complex, which is essential for exocytosis. Crystallization of this complex revealed a four-helix bundle with an unusual hydrophilic layer (zero layer) in its center. In order to evaluate the role of this layer in different kinetic components of secretion, we used the Semliki Forest virus (SFV) system to infect adrenal chromaffin cells with SNAP-25 Q174L, a point mutant in the zero layer. Using combined flash photolysis of caged calcium and membrane capacitance measurements, we investigated its effect on the exocytotic burst and sustained phase of exocytosis with high time resolution. Cells expressing SNAP-25 Q174L displayed a selective reduction in the sustained phase, while the two components of the exocytotic burst remained unaffected. Furthermore, the exocytotic response to the second flash was significantly reduced, indicating a decrease in refilling kinetics. We therefore conclude that the zero layer is critical for the formation of SNARE complexes, but that it plays no role in the dynamic equilibrium between the two exocytosis-competent vesicle pools.
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233
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An Z, Wei S, Xu S, Zhao G. [Effects of homoharringtonine on proliferation of human retro-ocular fibroblasts]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 2000; 31:95-7. [PMID: 12501627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
This is a study amied at the effects of homoharringtonine on the proliferation of human retro-ocular fibroblasts. The human retroocular fibroblasts (HROFb) were cultured and MTT colorimetry assay was used to determine the proliferation of HROFb. The influence of homoharringtonine on the proliferation of HROFb was observed in vitro. The results showed that MTT colorimetry assay could precisely reflect the proliferation of HROFb. The absorbance was directly proportional to the number of the cells (r = 0.996, P < 0.001). The proliferation of HROFb was inhibited by the homoharringtonine and the cell proliferation percentage was correlated positively to the homoharringtonine level (r = 0.6932, P < 0.001).
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234
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Zhao W, O'Malley Y, Wei S, Robbins ME. Irradiation of rat tubule epithelial cells alters the expression of gene products associated with the synthesis and degradation of extracellular matrix. Int J Radiat Biol 2000; 76:391-402. [PMID: 10757319 DOI: 10.1080/095530000138736] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
PURPOSE To determine the ability of radiation to modulate kidney tubule epithelial cell expression of various molecules involved in regulating extracellular matrix accumulation (collagen types I and III, fibronectin, plasminogen activator-inhibitor 1 (PAI-1), TGF-beta and tissue inhibitor of metalloproteinases-2 (TIMP-2)) and degradation (plasminogen activators u-PA or t-PA, MMP-2 and MMP-9). MATERIALS AND METHODS NRK52E rat tubule epithelial cells were placed in serum-free medium 24 h prior to irradiation with single doses of 1.0-10.0 Gy 137Cs gamma-rays. After irradiation, cells were maintained in serum-free medium for up to 48 h. RESULTS Irradiation of NRK52E cells was associated with significant dose-dependent increases in collagen I (p<0.05) and PAI-1 (p< or =0.002) mRNA. Collagen III mRNA levels also exhibited a dose-dependent increase; however, this increase failed to reach levels that were statistically significant. Fibronectin mRNA levels were unaltered following irradiation. Radiation also led to an isoform-specific alteration in TGF-beta expression; TGF-beta1 mRNA increased, TGF-beta3 mRNA decreased. The amount of TGF-beta protein secreted into the medium was unchanged following irradiation; however, there was a fivefold increase in the relative amount of active TGF-beta. Irradiation was also associated with differential changes in MMP expression: active MMP-2 levels increased, while MMP-9 levels were unaltered; PA secretion into the medium was unchanged following irradiation. CONCLUSIONS Irradiation of rat kidney tubule epithelial cells leads to altered production of various molecules associated with extracellular matrix accumulation and degradation.
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235
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Zhang SB, Wei S, Zunger A. Microscopic origin of the phenomenological equilibrium "Doping limit Rule" in n-type III-V semiconductors. PHYSICAL REVIEW LETTERS 2000; 84:1232-1235. [PMID: 11017486 DOI: 10.1103/physrevlett.84.1232] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/1999] [Indexed: 05/23/2023]
Abstract
The highest equilibrium free-carrier doping concentration possible in a given material is limited by the "pinning energy" which shows a remarkable universal alignment in each class of semiconductors. Our first-principles total energy calculations reveal that equilibrium n-type doping is ultimately limited by the spontaneous formation of close-shell acceptor defects: the (3-)-charged cation vacancy in AlN, GaN, InP, and GaAs and the (1-)-charged DX center in AlAs, AlP, and GaP. This explains the alignment of the pinning energies and predicts the maximum equilibrium doping levels in different materials.
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236
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Ma S, Cornford ME, Vahabnezhad I, Wei S, Li X. Responses of nitric oxide synthase expression in the gracile nucleus to sciatic nerve injury in young and aged rats. Brain Res 2000; 855:124-31. [PMID: 10650138 DOI: 10.1016/s0006-8993(99)02379-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Neuronal nitric oxide synthase (nNOS) is induced in dorsal root ganglion neurons following axotomy in young rats, and is also increased in the gracile nucleus neurons of intact aged rats. The present study examined the influence of sciatic nerve axotomy on nNOS expression in the gracile nucleus in young compared to aged rats. The unilateral transection of the sciatic nerve was performed in young (4 months) and old (24 months) Fischer rats. Sections of rat medulla obtained 14 days after axotomy were immunolabelled using a polyclonal antibody directed against nNOS and stained by nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) histochemistry, a marker of nNOS activity. In young rats, unilateral axotomy produced increased NADPHd containing neurons in the rostral region and the caudal region of the ipsilateral gracile nucleus compared to the side with intact sciatic nerve. In old rats, the NADPHd containing neurons in the ipsilateral gracile nucleus were moderately increased by axotomy over the age changes seen in the contralateral side. Similar results were obtained with nNOS immunoreactivity in young rats, but more cells were seen with NADPHd staining compared to nNOS immunostaining in old rats. The results suggest that unilateral sciatic axotomy causes an increase in nNOS expression in the ipsilateral gracile nucleus of young rats, which is still seen in old rats as an increase over normal aging changes.
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237
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Wei S, Wang H. [Informatics of dental medicine]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 2000; 18:61-2. [PMID: 12539368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Dental informatics is a newly developed discinpline which is integrated by modern stomatology, computer sciences and informatics. In this paper, the concept, importance, basic principle and contents were discussed in details. The relationship among dental informatics and related sciences, the formation and history of dental informatics were also described in this paper.
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238
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Inoue M, Ross FP, Erdmann JM, Abu-Amer Y, Wei S, Teitelbaum SL. Tumor necrosis factor alpha regulates alpha(v)beta5 integrin expression by osteoclast precursors in vitro and in vivo. Endocrinology 2000; 141:284-90. [PMID: 10614649 DOI: 10.1210/endo.141.1.7285] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Early osteoclast precursors, in the form of murine bone marrow macrophages (BMMs), while expressing no detectable alpha(v)beta3 integrin, contain abundant alpha(v)beta5 and attach to matrix in an alpha(v) integrin-dependent manner. Furthermore, alpha(v)beta5 expression by osteoclast precursors progressively falls as they assume the resorptive phenotype. We find the osteoclastogenic agent, tumor necrosis factor-alpha, (TNF) down-regulates alpha(v)beta5 expression by BMMS via attenuation of beta5 messenger RNA (mRNA) t1/2. Using BMMs from TNF receptor knockout mice we establish the p55 receptor transmits the beta5 suppressive effect. The functional implications of TNF-mediated alpha(v)beta5 down-regulation are underscored by the capacity of an alpha(v) inhibitory peptide mimetic to prevent spreading by BMMs expressing abundant alpha(v)beta5 while failing to impact those in which the integrin has been diminished by TNF. Finally, beta5 mRNA in BMMs of wild-type mice administered lipopolysaccharide (LPS) progressively falls with time of in vivo treatment. Alternatively, beta5 mRNA does not decline in BMMs of LPS-treated mice lacking both TNF receptors, documenting down-regulation of the beta5 integrin subunit, in vivo, is mediated by TNF. Thus, matrix attachment of osteoclast precursors and mature osteoclasts are governed by distinct alpha(v) integrins which are differentially regulated by specific cytokines.
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MESH Headings
- Animals
- Antigens, CD/biosynthesis
- Antigens, CD/genetics
- Blotting, Northern
- Cell Differentiation/drug effects
- Down-Regulation
- Gene Expression Regulation/genetics
- In Vitro Techniques
- Integrins/biosynthesis
- Integrins/genetics
- Lipopolysaccharides/pharmacology
- Macrophages/drug effects
- Macrophages/metabolism
- Male
- Mice
- Mice, Transgenic
- Osteoclasts/metabolism
- Osteoclasts/ultrastructure
- Osteogenesis/genetics
- Osteogenesis/physiology
- Precipitin Tests
- RNA, Messenger/biosynthesis
- Receptors, Tumor Necrosis Factor/biosynthesis
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor, Type I
- Receptors, Vitronectin
- Transcription, Genetic/genetics
- Tumor Necrosis Factor-alpha/agonists
- Tumor Necrosis Factor-alpha/physiology
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239
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Morell RJ, Friderici KH, Wei S, Elfenbein JL, Friedman TB, Fisher RA. A new locus for late-onset, progressive, hereditary hearing loss DFNA20 maps to 17q25. Genomics 2000; 63:1-6. [PMID: 10662538 DOI: 10.1006/geno.1999.6058] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We report the localization of DFNA20, a gene causing dominant, nonsyndromic, progressive hearing loss in a three-generation Midwestern family, to chromosome 17q25. Affected family members show a bilateral, sloping, progressive, sensorineural hearing loss, first evident at 6000 and 8000 Hz, that can be identified in some family members in the early teens and is clearly evident by the early twenties. As age increases, the degree of hearing loss increases with threshold shifts seen at all frequencies. Linkage to known hereditary hearing loss loci was excluded. A genome-wide screen detected positive linkage to D17S784 (LOD(Z) = 6.62; θ = 0). Haplotype analysis refines the DFNA20 critical region to 12 cM between D17S1806 and D17S668. Radiation hybrid mapping with Stanford G3 and TNG panels was used to evaluate the genes ACTG1, GRIN2C, FKHL13, P4HB, SPARC, and ARHGDIA as candidates for DFNA20.
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240
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Shen Z, Zhang Q, Wei S, Nagai T. Proteolytic enzymes as a limitation for pulmonary absorption of insulin: in vitro and in vivo investigations. Int J Pharm 1999; 192:115-21. [PMID: 10567743 DOI: 10.1016/s0378-5173(99)00295-1] [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: 11/27/2022]
Abstract
In vitro biodegradation of insulin in lung cytosol and subcellular pellets of normal and diabetic rats was investigated. Rat lung was homogenized and subcellular fractions were isolated by ultracentrifugation. Degradations of [125I]-insulin after incubation with lung cytosol or subcellular pellets was determined using the trichloroacetic acid method. The results show that insulin is highly degraded in cytosol and subcellular pellets. Cytosolic insulin degradation was strongly inhibited by bacitracin or sodium cholate. The degradation of insulin in the lung cytosol from diabetic rats was significantly less than from normal rat. The lung protease activity reached a maximum at pH 7.4. Enzyme inhibitors like bacitracin and sodium cholate noticeably enhanced the relative pharmacological bioavailability of insulin when given intratracheally with insulin to normal rats. Acidic insulin solutions (pH 3.0) had more pronounced hypoglycaemic effects than neutrol solution (pH 7.0). These in vitro and in vivo results suggest that the proteolytic enzymes in the lung limit pulmonary delivery of insulin. The coadministration of protease inhibitors would be a useful approach for improving the pulmonary absorption of insulin.
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241
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Sugiura K, Miyake T, Taniguchi Y, Yamada T, Moralejo DH, Wei S, Wei K, Sasaki Y, Matsumoto K. Identification of novel non-insulin-dependent diabetes mellitus susceptibility loci in the Otsuka Long-Evans Tokushima fatty rat by MQM-mapping method. Mamm Genome 1999; 10:1126-31. [PMID: 10594234 DOI: 10.1007/s003359901177] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The Otsuka Long-Evans Tokushima Fatty (OLETF) rat is an animal model for obese-type, non-insulin-dependent diabetes mellitus (NIDDM) in humans. We have previously identified 11 quantitative trait loci (QTLs) responsible for NIDDM susceptibility on Chromosomes (Chrs) 1, 5, 7, 8, 9, 11, 12, 14, and 16 (Nidd1-11/of for Non-insulin-dependent diabetes 1-11/oletf) by using the interval mapping method in 160 F(2) progenies obtained by mating the OLETF and the Fischer-344 (F344) rats. MQM-mapping, which was applied for QTL analysis based on multiple-QTL models, is reported to be more powerful than interval mapping, because in the process of mapping one QTL the genetic background, which contains the other QTLs, is controlled. Application of MQM-mapping in the F(2) intercrosses has led to a revelation of three novel QTLs on rat Chrs 5 (Nidd12/of), 7 (Nidd13/of), and 17 (Nidd14/of), in addition to Nidd1-11/of loci. The three QTLs, together with the Nidd1-11/of, account for a total of approximately 70% and approximately 85% of the genetic variance of the fasting and postprandial glucose levels, respectively, in the F(2). While the OLETF allele corresponds with increased glucose levels as expected for Nidd12 and 14/of, the Nidd13/of exhibits heterosis: heterozygotes showing significantly higher glucose levels than OLETF or F344 homozygotes. There is epistatic interaction between Nidd2 and 14/of. Additionally, our results indicated that the novel QTLs could show no linkage with body weight, but Nidd12/of has an interaction with body weight.
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242
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Wei K, Izumi K, Hino A, Wei S, Sasaki Y, Yamada T, Matsumoto K. Identification of a locus for susceptibility to renal cell carcinoma in the Long-Evans Cinnamon rat. J Vet Med Sci 1999; 61:1261-4. [PMID: 10593588 DOI: 10.1292/jvms.61.1261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Long-Evans Cinnamon (LEC) mutant rat shows higher incidence of renal cell carcinomas induced by a treatment with the chemical carcinogen N-diethylnitrosamine, as compared to the normal control rat. We performed the first genome-wide scan for genes responsible for susceptibility to chemically induced renal cell carcinoma in an F2 intercross obtained by mating the LEC and Fischer-344 (F344) rats. The genotype of 71 (F344 x LEC) F2 progenies was determined with the use of 338 simple sequence length polymorphisms (SSLPs) spread over the genome. The F2 rats which carried renal cell carcinoma were shown to possess the incidence of homozygosity of the LEC allele which is higher than that of the other genotypes at SSLP markers on chromosome 5 (chi2 = 17.5 for D5Rat21). Our linkage analysis has led to the revelation of a novel gene that influences susceptibility to renal cell carcinoma on rat chromosome 5.
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243
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Shang Q, Liu C, Wei S, Shi F, Yang A. [Wavelength selection in management of central serous chorioretinopathy]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1999; 35:413-5. [PMID: 11835848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To compare the effects of three kinds of laser wavelength in management of central serous chorioretinopathy (CSCR). METHOD 89 patients with CSCR were randomly divided into three groups according to different wavelengths used. Visual acuity, fundus, fundus fluorescein angiography (FFA), light sensitivity, central visual field were performed before and after laser therapy. RESULT Compared with red and green wavelength groups, in yellow group the visual acuity, light sensitivity were improved more significantly (P < 0.05), and the disease course was shortened, the effects in recurrence rate were similar in the three wavelength groups. CONCLUSION In the three kinds of waves, yellow and red have similar and positive effects in the treatment of CSCR.
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Huang R, Li D, Wei S, Li Q, Yuan X, Geng L, Li X, Liu M. Cell culture of sporadic hepatitis E virus in China. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 1999; 6:729-33. [PMID: 10473526 PMCID: PMC95763 DOI: 10.1128/cdli.6.5.729-733.1999] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The isolation and identification of the 87A strain of epidemic hepatitis E virus (HEV) by means of cell culturing have been described previously. This paper reports the successful isolation of a sporadic HEV strain (G93-2) in human lung carcinoma cell (A549) cultures. The etiology, molecular and biological properties, and serological relationship of this new strain to other, epidemic HEV strains are described. The propagation of both sporadic and epidemic HEV strains in a cell culture system will facilitate vaccine research.
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245
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Abstract
Carcinogenesis involves the accumulation of genetic changes within a single cell. Tumor promotion functions in the initial clonal expansion of an initiated cell but is generally not considered to influence later stages. To investigate whether tumor promotion can influence later stages of carcinogenesis we developed a two-hit 7, 12-dimethylbenz[a]anthracene (D) protocol designed to enrich for keratinocytes that contain at least two D-induced genetic alterations. FVB/N mice were initiated with D and promoted with 12-O-tetradecanoylphorbol-13-acetate (T) or treated with acetone (A) vehicle for 6 weeks. At 7 weeks after the start of promotion, but before visible papilloma development, groups of mice were treated with a second dose of D or A and 1 week later T promotion was resumed. D/T/A/T mice developed 2.8 papillomas/mouse and D/A/D/T mice demonstrated an additive tumor response and developed 5.8 papillomas/mouse. Importantly, D/T/D/T mice developed 12.4 papillomas/mouse, thereby demonstrating a synergistic tumor response compared with D/A/D/T and D/T/A/T mice. D/T/D/T papillomas exhibited increases in suprabasal S phase cells and keratin 13 expression when compared with D/T/A/T papillomas. D/T/D/T mice developed squamous cell carcinomas (SCCs) 10 weeks earlier than D/T/A/T mice and demonstrated a 96% malignancy incidence and 1.71 SCC/mouse compared with D/T/A/T mice, which demonstrated a 28% malignancy incidence and 0.32 SCC/mouse. Greater than 90% of D/T/A/T and D/T/D/T papillomas and SCCs contained mutant Ha-ras, while a normal Ha-ras allele persisted in all cases, indicating that a gene other than the remaining normal allele of Ha-ras was a target gene for the second D hit. These data demonstrate that: (i) promotion between the first and second hits has a profound outcome on carcinogenesis, presumably by increasing the probability that a second hit will occur in a previously initiated cell; (ii) continued promotion after the second hit is required for full expression of malignancy; (iii) the classic initiation-promotion protocol can be extended to a multihit, multistage model.
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MESH Headings
- 9,10-Dimethyl-1,2-benzanthracene/toxicity
- Acetone/toxicity
- Animals
- Carcinogens/toxicity
- Carcinoma, Squamous Cell/chemically induced
- Carcinoma, Squamous Cell/pathology
- Cell Transformation, Neoplastic/chemically induced
- Cell Transformation, Neoplastic/genetics
- Cocarcinogenesis
- DNA Mutational Analysis
- DNA, Neoplasm/genetics
- Female
- Gene Expression Regulation, Neoplastic
- Genes, ras
- Keratinocytes/drug effects
- Keratinocytes/pathology
- Keratins/biosynthesis
- Keratins/genetics
- Mice
- Models, Biological
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Papilloma/chemically induced
- Papilloma/pathology
- Polymerase Chain Reaction
- Polymorphism, Single-Stranded Conformational
- S Phase
- Skin Neoplasms/chemically induced
- Skin Neoplasms/pathology
- Tetradecanoylphorbol Acetate/toxicity
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246
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Wei S, Ageron-Blanc A, Petridis F, Beaumatin J, Bonnet S, Luccioni C. Radiation-induced changes in nucleotide metabolism of two colon cancer cell lines with different radiosensitivities. Int J Radiat Biol 1999; 75:1005-13. [PMID: 10465366 DOI: 10.1080/095530099139764] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
PURPOSE To investigate changes in nucleotide metabolism after irradiation. MATERIALS AND METHODS HT29 and SW48 human colon carcinoma cells were exposed to 60Co gamma-rays at doses ranging from 0 to 7.5 Gy. At different times after irradiation, the activities of nine enzymes involved in nucleotide metabolism were measured, the levels of thymidine kinase and deoxycytidine kinase proteins were evaluated by Western blot, and cell-cycle kinetics were analysed by flow cytometry. RESULTS Changes in enzyme activities concerned not purine but pyrimidine metabolism and essentially the salvage pathway for deoxyribonucleotide synthesis. They were greater in the less radiosensitive HT29 cells. The levels of thymidine kinase and deoxycytidine kinase proteins changed in parallel with their activities. The metabolic changes in irradiated cells did not seem to be due to S-phase transition and the pattern of enzyme activity changes was different from that observed in proliferative cells. CONCLUSIONS Radiation-induced changes in the salvage pathway for pyrimidine deoxyribonucleotide synthesis were observed. These findings could be exploited in cancer therapy because higher enzyme activities after irradiation suggest that radiation exposure may render cells more sensitive to the drugs activated by these enzymes.
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247
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Wei S, Reillaudou M, Apiou F, Peyre H, Pétridis F, Luccioni C. Purine metabolism in two human melanoma cell lines: relation to proliferation and differentiation. Melanoma Res 1999; 9:351-9. [PMID: 10504053 DOI: 10.1097/00008390-199908000-00003] [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: 11/26/2022]
Abstract
Purine nucleotide metabolism was studied in two human cutaneous melanoma cell lines IPC182 and IGR221. IPC182 cells do not differentiate, while IGR221 cells differentiate spontaneously at confluency, with intense melanin production. The activities of 11 enzymes involved in the de novo or salvage synthesis or the catabolic pathway of purine nucleotides were measured at different times (from day 3 to day 18), after subculture, during exponential growth and the stationary phase, with or without differentiation. The results demonstrated remarkable differences in the enzyme activity levels and/or the evolution from exponential growth to the stationary phase for each cell line, as well as between the two cell lines. In the non-differentiating IPC182 cells, the activity of enzymes involved in purine nucleotide synthesis decreased when the growth rate slowed down and remained at a low level with a concomitant increase in catabolic activities. In the differentiating IGR221 cells, the activity of enzymes involved in purine nucleotide salvage synthesis increased during the proliferative phase and was maintained at a high level when the cells reached confluency and differentiated; catabolic activities were always lower than in the IPC182 cells. This suggests that extra purine nucleotides, synthesized preferentially by the salvage pathway, could be required for the differentiation of human melanoma cells. Since the two cell lines were cultured in the absence of any differentiation-inducing agents, these results indicate that various metabolic modifications are associated with the natural processes of cell proliferation and differentiation. This research could help to identify some of the enzymes involved in purine metabolism as the targets for the induction of differentiation.
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248
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Wei K, Wei S, Moralejo DH, Yamada T, Ogino T, Matsumoto K. An efficient multiplex PCR suitable for large scale typing in linkage mapping. J Vet Med Sci 1999; 61:849-51. [PMID: 10458113 DOI: 10.1292/jvms.61.849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The dissection of polygenic traits is made possible with the development of microsatellite markers. Linkage study of this kind involves many markers with tens of hundreds of samples. Although typing essentially contains only two steps: PCR amplification and gel electrophoresis. Such work is still heavy when a large number of samples had to be genotyped. Multiplex PCR may reduce the work, but one has to optimize the conditions from marker to marker. Here we describe a dye-compatible multiplex PCR that works under standardized condition without the need to pre-determine the combinational primer concentration and the time-consuming step to mix many samples with gel loading dye before electrophoresis. This successful protocol should greatly reduce the cost and labor for genetic study of polygenic traits.
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249
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Shang Q, Liu C, Wei S, Shi F, Li Y, Qiao L. [Determination of cortisol in plasma and 24-hour urine of patients with central serous chorioretinopathy]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1999; 35:297-9. [PMID: 11835828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To study the cortisol levels in patients with central serous chorioretinopathy (CSCR). METHODS Endogenous cortisol levels in plasma and urine were determined in 44 patients with CSCR by radioimmunoassay and chromatography, and their results were compared with that of 41 controls. RESULTS In acute CSCR, the mean values of the plasma cortisol (296.53 +/- 77.03) ng/ml and 24-hour urine 17-hydroxysteroids (the major metabolite of cortisol metabolism) (12.08 +/- 4.82) mg/24 h revealed significantly higher values in the patient group (P < 0.05). CONCLUSIONS Increased levels of endogenous cortisol play a role in the development of CSCR.
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250
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Zhang H, Shepherd AT, Eason DD, Wei S, Diaz JI, Djeu JY, Wu GD, Blanck G. Retinoblastoma protein expression leads to reduced Oct-1 DNA binding activity and enhances interleukin-8 expression. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 1999; 10:457-65. [PMID: 10437913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Tumor cell lines with a defective retinoblastoma gene are unable to transcribe the HLA class II genes in response to IFN-gamma treatment, and reconstitution of functional Rb rescues IFN-gamma-induced class II gene expression. However, the molecular mechanism of Rb rescue of the class II genes is unknown. We have examined the effect of Rb expression on the activation of the promoter for HLA-DRA, the prototype class II gene. Oct-1, a POU domain transcription factor, was identified as a repressor of HLA-DRA promoter activity in the Rb-defective cells. Rb expression led to phosphorylation of Oct-1, thus relieving its repressive effect. Oct-1 has also been shown to repress interleukin 8 promoter activity. Consistent with reduced levels of Oct-1 DNA binding activity in the Rb-transformed cell lines, interleukin 8 expression is higher in these cell lines.
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