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Tsai IH, Wang YM, Au LC, Ko TP, Chen YH, Chu YF. Phospholipases A2 from Callosellasma rhodostoma venom gland cloning and sequencing of 10 of the cDNAs, three-dimensional modelling and chemical modification of the major isozyme. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:6684-91. [PMID: 11054123 DOI: 10.1046/j.1432-1327.2000.01766.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Callosellasma rhodostoma (Malayan pitviper) is a monotypic Asian pitviper of medical importance. Three acidic phospholipases A2 (PLA2s) and one basic PLA2-homolog were purified from its venom while 10 cDNAs encoding distinct PLA2s were cloned from venom glands of a Thailand specimen of this species. Complete amino-acid sequences of the purified PLA2s were successfully deduced from their cDNA sequences. Among the six un-translated PLA2 cDNAs, two apparently result from recombination of its Lys49-PLA2 gene with its Asp49-PLA2 genes. The acidic PLA2s inhibit platelet-aggregation, while the noncatalytic PLA2-homolog induces local edema. This basic PLA2-homolog contains both Asp49 and other, unusual substitutions unique for the venom Lys49-PLA2 subtype (e.g. Leu5, Trp6, Asn28 and Arg34). Three-dimensional modelling of the basic protein revealed a heparin-binding region, and an abnormal calcium-binding pocket, which may explain its low catalytic activity. Oxidation of up to six of its Met residues or coinjection with heparin reduced its edema-inducing activity but methylation of its active site His48 did not. The distinct Arg/Lys-rich and Met-rich region at positions 10-36 of the PLA2 homolog presumably are involved in its heparin-binding and the cell membrane-interference leading to edema and myotoxicity.
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Chang JB, Chen YH, Chu NF. Relationship between single voided urine protein/creatinine ratio and 24-hour urine protein excretion rate among children and adolescents in Taiwan. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2000; 63:828-32. [PMID: 11155760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND As there have been few studies conducted on children or adolescents, the purpose of this study was evaluate the relationship between single voided urine protein/creatinine (Up/Ucr) ratio and 24-hour urine protein excretion rate (PER), especially among children and adolescents in Taiwan. METHODS After multistage random sampling, we collected 1,072 fasting single voided urine samples and 125 24-hour urine samples from seven- to 18-year-old students in Taiwan. We calculated the Up/Ucr of single voided urine samples and the 24-hour PER in urine. RESULTS The mean value and the 95th percentile of the fasting single voided urine Up/Ucr ratio were 0.118 and 0.235, respectively. The mean value and the 95th percentile of the 24-hour PER were 3.61 and 5.66 mg/h/m2, respectively. There was no significant difference in Up/Ucr ratio between boys and girls. Up/Ucr ratio decreased significantly as age increased. The fasting single voided Up/Ucr ratio was highly correlated with 24-hour PER, with r2 = 0.95 (p < 0.001). CONCLUSIONS Fasting single voided Up/Ucr ratio is a good marker of 24-hour PER. It is also a simple, easy, convenient and speedy method to measure Up excretion. The single voided Up/Ucr ratio may also serve as a reference for the clinical diagnosis of Up excretion among normal subjects.
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Miller KP, Chen YH, Hastings VL, Bral CM, Ramos KS. Profiles of antioxidant/electrophile response element (ARE/EpRE) nuclear protein binding and c-Ha-ras transactivation in vascular smooth muscle cells treated with oxidative metabolites of benzo[a]pyrene. Biochem Pharmacol 2000; 60:1285-96. [PMID: 11008122 DOI: 10.1016/s0006-2952(00)00439-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Activation of nuclear protein binding to the antioxidant/electrophile response element (ARE/EpRE) by benzo[a]pyrene (BaP) in vascular smooth muscle cells (vSMCs) is associated with transcriptional deregulation of c-Ha-ras. This response may be mediated by oxidative intermediates of BaP generated during the course of cellular metabolism. To test this hypothesis, the profile of ARE/EpRE protein binding and transactivation elicited by BaP was compared with that of 3-hydroxy BaP (3-OH BaP) (0.03 to 3.0 microM), BaP 7,8-dihydrodiol (BaP 7,8-diol) (0.03 to 3.0 microM), BaP 3,6-quinone (BaP 3,6-Q) (0.0003 to 3.0 microM), and H(2)O(2) (25 to 100 microM). Specific protein binding to the consensus c-Ha-ras ARE/EpRE was observed in vSMCs treated with all BaP metabolites at concentrations considerably lower than those required for the parent compound. H(2)O(2), a by-product of BaP 3,6-Q redox cycling, also increased binding to the ARE/EpRE. Treatment of vSMCs with oxidative BaP metabolites or H(2)O(2) transactivated the c-Ha-ras promoter in all instances, but the response was consistently half of the maximal induction elicited by BaP. Similar proteins cross-linked specifically to the consensus c-Ha-ras ARE/EpRE sequence in cells treated with BaP or its oxidative intermediates. The protein binding profile in the c-Ha-ras promoter was similar to that in the NADPH:quinone reductase gene (NQO(1)) and the glutathione S-transferase Ya gene (GSTYa) promoters, but the relative abundance of individual complexes was promoter-specific. We conclude that oxidative intermediates of BaP mediate activation of nuclear protein binding to ARE/EpRE and contribute to transcriptional de-regulation of c-Ha-ras in vSMCs.
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304
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Zhu CQ, Lam TH, Jiang CQ, Wei BX, Xu QR, Chen YH. Increased lymphocyte DNA strand breaks in rubber workers. Mutat Res 2000; 470:201-9. [PMID: 11027975 DOI: 10.1016/s1383-5718(00)00106-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To study the effect of occupational exposure to rubber processing, smoking, and alcohol drinking on lymphocyte DNA damage. SUBJECTS AND METHODS Of 371 employees (197 men and 174 women) from a rubber factory in Guangzhou, 281 were rubber processing workers from five production sections and 90 were managerial workers. Information on occupational exposure, smoking, and drinking was collected by interviews. Blood samples were taken in the morning by venipuncture. DNA damages were measured by the Comet assay. Possible DNA-protein crosslinks were broken down by proteinase K. Tail moment, measured by Komet 4.0 image analysis software, was the measure of DNA damage. RESULTS The rubber processing workers had larger tail moment than the managerial workers (Geometric mean, 95%CI) [1. 77microm (1.64-1.90) versus 1.52microm (1.36-1.71), P=0.04]. Both smoking [1.93microm (1.74-2.13) versus 1.59microm (1.47-1.71), P=0. 003] and alcohol drinking [2.21microm (1.87-2.62) versus 1.63microm (1.53-1.74), P<0.001] increased tail moment. Tail moment differed significantly among job categories (F=3.21, P=0.008), the largest was observed in mixers. In the non-smoking and non-drinking workers, rubber processing workers had larger tail moment than managerial workers after adjusting for age (P=0.033). General linear model analysis showed that after adjusting for each other, occupational exposure (P=0.027), smoking (P=0.012), and alcohol drinking (P=0. 013) was associated with larger tail moment, whereas age and gender had no effect. CONCLUSIONS Occupational exposure to rubber processing, smoking, and alcohol drinking can cause DNA damage.
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305
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Szekely AM, Chen YH, Zhang C, Oshima J, Weissman SM. Werner protein recruits DNA polymerase delta to the nucleolus. Proc Natl Acad Sci U S A 2000; 97:11365-70. [PMID: 11027336 PMCID: PMC17206 DOI: 10.1073/pnas.97.21.11365] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Werner syndrome is a Mendelian disorder of man that produces a number of manifestations resembling human aging. This disorder is caused by inactivation of the wrn gene, a member of the RecQ family of DNA helicases. The helicase and exonuclease activities of the Werner protein (WRN) suggest that it functions in DNA transactions, but the physiological function of WRN remains elusive. We present several lines of evidence that WRN interacts specifically with the p50 subunit of polymerase delta, the major DNA polymerase required for chromosomal DNA replication. P50, identified by yeast two-hybrid screening, interacts physically with the C terminus of WRN. Native WRN protein coimmunoprecipitates with p50 in a cellular fraction enriched in nucleolar proteins, and this immunocomplex also includes p125, the catalytic subunit of polymerase delta. In subcellular localization studies of cells transfected with WRN, p50 and p125 redistribute to the nucleolus and colocalize with WRN. These results suggest that one of the functions of WRN protein is to directly modify DNA replication via its interaction with p50 and abet dynamic relocalization of the DNA polymerase delta complexes within the nucleus.
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306
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Yu JG, Yu DL, Zhang S, Luo XZ, Sun L, Zheng CC, Chen YH. [Studies on the chemical constituents of Kaempferia marginata]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2000; 35:760-3. [PMID: 11372443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
AIM To study the chemical constituents of the rhizomes of Kaempferia galanga L. (Zingiberaceae). METHODS Various chromatographic techniques were used to separate and purify. Their physico-chemical properties and spectral data were used to elucidate the structures. RESULTS Six compounds were isolated from the hexane extract of K. galanga. Their structures were identified as marginatol (1), 8 (14), 15-sanderacopimaradiene-1 alpha, 9 alpha-diol (2), 8 (14), 15-sanderacopimaradiene-1 alpha, 6 beta, 9 alpha-triol (3), germacrone (4), trans-ethyl p-methoxycinnamate (5) and n-pentadecane (6) on the basis of spectral data (IR, MS, 1H-1H, 13C-1H NMR, NOEs and HMBC). CONCLUSION Marginatol (1) is a new isopimarene diterpenoid and was elucidated as 8(14), 15-isopimaradiene-6 alpha-ol. Compounds 2, 3 and 4 were isolated for the first time from this plant.
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307
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Chen YH, He RQ, Liu Y, Liu Y, Xue ZG. Effect of human neuronal tau on denaturation and reactivation of rabbit muscle D-glyceraldehyde-3-phosphate dehydrogenase. Biochem J 2000; 351:233-40. [PMID: 10998366 PMCID: PMC1221354 DOI: 10.1042/0264-6021:3510233] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Human neuronal tau-40 (htau-40) has been used to study denaturation and renaturation of rabbit muscle D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12). Inactivation of GAPDH incubated with tau was more distinguishably detected than that of control GAPDH during thermal and guanidine hydrochloride (GdnHCl) denaturation. However, tau did not influence the activity of GAPDH at room temperature or in solution without GdnHCl. A marked change in both the emission intensity and emission maximum of the intrinsic fluorescence at 335 nm of GAPDH with tau was observed when GdnHCl concentration was 0.8 M, but that of the control without tau occurred in 1.2 M GdnHCl. The first-order rate of the decrease in the fluorescence intensity of the enzyme with tau was approximately twice as great as that of GAPDH without tau. Kinetics of inactivation of GAPDH with tau in 0.2 M GdnHCl was a monophasic procedure, instead of the biphasic procedure followed by the control, as described before [He, Zhao, Yan and Li (1993) Biochim. Biophys. Acta 1163, 315-320]. Similar results were obtained when the enzyme was thermally denatured at 45 degrees C. It revealed that tau bound to the denatured GAPDH but not the native molecule. On the other hand, tau suppressed refolding and reactivation of GAPDH when this enzyme was reactivated by dilution of GdnHCl solution. Furthermore, tau improved the aggregation of the non-native GAPDH in solutions. It suggested that tau acted in an anti-chaperone-like manner towards GAPDH in vitro. However, tau lost that function when it was aggregated or phosphorylated by neuronal cdc2-like protein kinase. It showed that tau's anti-chaperone-like function depended on its native conformation.
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308
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Tan XD, Chen YH, Liu QP, Gonzalez-Crussi F, Liu XL. Prostanoids mediate the protective effect of trefoil factor 3 in oxidant-induced intestinal epithelial cell injury: role of cyclooxygenase-2. J Cell Sci 2000. [PMID: 10825288 DOI: 10.1016/s0016-5085(00)84896-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Trefoil factors are small peptides found in several mammalian tissues including gut, respiratory tract and brain. Their physiological function is not well understood. Among them, trefoil factor 3 (intestinal trefoil factor) is known to be cytoprotective in the gut. However, the molecular mechanism and secondary mediators of trefoil factor 3 action are not known. In the present study, we examined whether the cyclooxygenase pathway is involved in trefoil factor 3 action. We showed that trefoil factor 3 significantly induces the production of prostaglandin E(2) and prostaglandin I(2) in IEC-18 cells (an intestinal epithelial cell line) in a dose dependent manner. Western blot and immunohistochemistry revealed that trefoil factor 3 (2.5 microM) up-regulates the expression of cyclooxygenase-2 but not cyclooxygenase-1 in IEC-18 cells. Treating cells with trefoil factor 3 (10 microM) significantly attenuated reactive oxygen species-induced IEC-18 cell injury. This effect is blocked by NS-398 (10 microM), a selective cyclooxygenase-2 inhibitor. Moreover, we demonstrated that exogenously administered carbacyclin (1 microM, a stable analogue of prostaglandin I(2)) and/or prostaglandin E(2) (1 microM) caused a significant reduction of reactive oxygen species-induced cell injury, mimicking the effect of trefoil factor 3. In summary, our results indicate that trefoil factor 3 activates cyclooxygenase-2 in intestinal epithelium to produce prostaglandin I(2) and prostaglandin E(2), which function as survival factors and mediate the cytoprotective action of trefoil factor 3 against oxidant injury.
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309
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Chu ST, Lee YC, Nein KM, Chen YH. Expression, immunolocalization and sperm-association of a protein derived from 24p3 gene in mouse epididymis. Mol Reprod Dev 2000; 57:26-36. [PMID: 10954853 DOI: 10.1002/1098-2795(200009)57:1<26::aid-mrd5>3.0.co;2-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The cDNA sequence for 24p3 protein in ICR mouse epididymal tissue was determined by PCR using primers designed according to the cDNA sequence derived from 24p3 protein in mouse uterine tissue. In the present study, 24p3 protein was immunolocalized in the epithelial cells and lumen of mouse epididymis. Both immunoblot analysis for protein and northern blot analysis for mRNA level showed a declining gradient of 24p3 expression from the caput to caudal region of the epididymis. The 24p3 protein was undetectable in the testis. These findings suggest that the 24p3 protein is a caput-initiated secretory protein in the mouse epididymis. A postnatal study revealed that 24p3 gene expression occurred in mice at the age of 14 days, before the completion of epididymal differentiation. This expression remained at a constant level until epididymal differentiation was completed. We also found that the secreted 24p3 protein interacted predominantly with the acrosome of caudal spermatozoa. Our findings suggest that the epididymal 24p3 protein is a caput-initiated and sperm-associated gene product and may be important in the reproductive system.
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310
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Chen YH. [Wavelet packet-based ECG compression]. ZHONGGUO YI LIAO QI XIE ZA ZHI = CHINESE JOURNAL OF MEDICAL INSTRUMENTATION 2000; 24:270-273. [PMID: 12583021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A wavelet packet-based algorithm for the compression of ECG is presented in the paper. The wavclet packet algorithm, which synthesizes the efficiency and the flexibility of the wavelet pacheket, generates significantly lower data rates with less computational effort.
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311
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Chen YH, Chang CH, Liang GJ, Huang SS, Hsieh HM, Teng CM, Tsai MC. Burst firing of action potentials in central snail neurons elicited by d-amphetamine: effect of anticonvulsants. Comp Biochem Physiol C Toxicol Pharmacol 2000; 127:221-31. [PMID: 11083032 DOI: 10.1016/s0742-8413(00)00144-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effect of anticonvulsants on the burst firing of action potentials in snail central neuron elicited by d-amphetamine was studied in the identified RP4 neuron of the African snail, Achatina fulica Ferussac. Oscillation of membrane potential and burst firing of action potentials were elicited by d-amphetamine in a concentration-dependent manner. Voltage clamped studies revealed that d-amphetamine elicited a negative slope resistance (NSR) in steady-state I-V curve between - 40 and - 10 mV. The burst firing of action potentials was alleviated following extracellular application of phenytoin, but was not affected after ethosuximide, carbamazepine, and valproic acid. The NSR elicited by d-amphetamine was blocked by phenytoin. However, the NSR was not altered if carbamazepine was added. These results suggest that of the four anticonvulsants tested, only phenytoin could alleviate the burst firing of action potentials elicited by d-amphetamine in snail neuron.
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Chern BY, Chen YH, Hong LS, Lapolt PS. Ovarian steroidogenic responsiveness to exogenous gonadotropin stimulation in young and middle-aged female rats. PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE. SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE (NEW YORK, N.Y.) 2000; 224:285-91. [PMID: 10964264 DOI: 10.1046/j.1525-1373.2000.22433.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Reproductive aging in the female rat is associated with gradual declines in LH secretion and ovarian progesterone (P) production. This study examined whether the influences of aging on P levels reflect decreased ovarian responsiveness to gonadotropin stimulation, as opposed to changes in gonadotropin release. Young and middle-aged regularly cyclic female rats received sodium pentobarbital to block endogenous proestrous luteinizing hormone (LH) surges, followed by administration of various doses of human chorionic gonadotropin (hCG). Similar treatments were performed in middle-aged acyclic persistent-estrous (PE) females. Injection of hCG resulted in equivalent plasma hCG levels in each treatment group. At the lowest hCG dose tested, a significant rise in plasma P levels was observed in middle-aged cyclic rats, but not in young cyclic or middle-aged PE females. This unexpected finding may reflect accelerated follicular development in middle-aged cyclic females, as suggested by a previous study. At the intermediate dose, young and middle-aged cyclic but not PE rats displayed significantly increased P in response to hCG. At the highest dose tested, all three groups of rats displayed increased P levels after hCG stimulation. However, P concentrations were significantly lower in middle-aged PE than regularly cyclic females. Northern and slot blot hybridization analyses revealed that ovarian mRNA levels for cytochrome P450 side-chain cleavage, the rate-limiting enzyme in P synthesis, were markedly reduced in PE rats following hCG stimulation. These findings indicate that ovarian responsiveness to gonadotropin stimulation is impaired in middle-aged PE, but not regularly cyclic rats, and suggest influences of cycle status on the biochemical and molecular mechanisms regulating ovarian steroid production. Furthermore, these findings reveal that attenuated P production in middle-aged proestrous rats is due to attenuated preovulatory LH surges, rather than decreased ovarian sensitivity to LH.
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313
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Chen YH, Ramos KS. A CCAAT/enhancer-binding protein site within antioxidant/electrophile response element along with CREB-binding protein participate in the negative regulation of rat GST-Ya gene in vascular smooth muscle cells. J Biol Chem 2000; 275:27366-76. [PMID: 10818089 DOI: 10.1074/jbc.m000405200] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Studies were conducted to evaluate the negative regulatory function of rat (r)GST-Ya antioxidant/electrophile response element (ARE/EpRE) in vascular smooth muscle cells (vSMCs). We report that CCAAT/enhancer-binding protein (C/EBP)-beta interacts with ARE/EpRE in the rGST-Ya promoter and that aryl hydrocarbon receptor (AhR) is present within the protein complex binding to the C/EBP site. Overexpression of C/EBP-beta or C/EBP-alpha repressed, whereas AhR enhanced, 1.6CAT reporter activity in cells treated with benzo(a)pyrene (BaP). Overexpression of CREB-binding protein (CBP) nullified repression of rGST-Ya transcription. Human adenovirus E1A protein abrogated cotransactivation by CBP but an E1A mutant did not. Overexpression of C/EBPs abrogated stimulation of 1.6CAT by CBP or AhR alone, or in combination, regardless of BaP treatment. Similar profiles were observed using an AhRECAT construct. The C/EBP site within the ARE/EpRE inhibited chemical inducibility of the AhRE. The pattern of mouse GST-Ya regulation by BaP was similar to that of rGST-Ya. We conclude that multiple mechanisms mediate negative regulation of GST-Ya gene in vSMCs, most significant of which are that C/EBP-beta inhibits AhRE or ARE/EpRE inducibility of GST-Ya, limiting CBP levels compromise gene induction, functional interference exists between AhRE and ARE/EpRE, and AhR alone, or in combination with C/EBP-beta, functions as a repressor of the ARE/EpRE.
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314
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Chen YH, Lee WC, Cheng CH, Tsai HJ. Muscle regulatory factor gene: zebrafish (Danio rerio) myogenin cDNA. Comp Biochem Physiol B Biochem Mol Biol 2000; 127:97-103. [PMID: 11126756 DOI: 10.1016/s0305-0491(00)00242-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Myogenin is one of the basic helix-loop-helix proteins that regulate muscle-specific gene expression. Using reverse transciption-polymerase chain reaction (RT-PCR), 5'- and 3'-rapid amplification of cDNA ends (RACE), zebrafish myogenin cDNA was cloned from mRNA of embryos at 10-96 h post-fertilization. The cDNA, at 1384 base pairs (bp), contained a 771-bp open reading frame with 113- and 500-bp flanking regions at the 5'- and 3'-ends, respectively. The deduced amino acid sequences of zebrafish myogenin encoded a 256-amino-acid polypeptide. In a comparison with myogenin of carp, trout, Xenopus, chicken and human, zebrafish myogenin shared 90.9, 77.6, 70.3, 62.9 and 51.5% amino acid identity, respectively. The basic helix-loop-helix domains in myogenin are all conserved. The molecular phylogenic tree demonstrated that myogenin of zebrafish is more closely related to that of fish than to the myogenin of other vertebrates.
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315
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Abstract
This study examined neurocognitive deficits as familial vulnerability factors to schizophrenia. Twenty-three Chinese schizophrenic patients, 21 of their non-psychotic siblings and 26 healthy volunteers, matched for age, sex and education, were assessed by using a battery of neurocognitive tests including: Wisconsin Card Sorting Test (WCST), semantic verbal fluency, logical memory, digit span, information, comprehension and similarity. The results showed that siblings had significantly less word output in the verbal fluency test as compared to controls. No significant difference was found between siblings and controls for other tests except that a trend difference was noted for the performance on the similarity test and number of categories completed on the WCST. The verbal fluency abnormality can be considered as a familial trait marker for schizophrenia. Relationships between the residual symptoms after an acute psychotic episode and the magnitude of familial risk were examined. More severe residual symptoms of probands at clinical remission could be predicted by their older age of onset and by better verbal fluency performance in their non-psychotic siblings. This tentatively suggests that patients with a milder genetic form of schizophrenic illness may have a more severe environmental contribution to cerebral insult according to the multifactorial/threshold model. The environmental cerebral insult may cause structural abnormalities leading to incomplete remission of clinical symptoms.
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316
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Chen YH, Lu Y, De Plaen IG, Wang LY, Tan XD. Transcription factor NF-kappaB signals antianoikic function of trefoil factor 3 on intestinal epithelial cells. Biochem Biophys Res Commun 2000; 274:576-82. [PMID: 10924320 DOI: 10.1006/bbrc.2000.3176] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Transcription factor NF-kappaB has both pro-apoptotic and anti-apoptotic properties depending on the cell type. Its role in the intestinal epithelial cell has not been well elucidated. Trefoil factor 3 (TFF3) is an anti-apoptotic peptide secreted by intestinal goblet cells. Here we show that TFF3 activated NF-kappaB p50/p65 heterodimer within 1 h in IEC-18 cells (a nontransformed rat intestinal epithelial cell line). Moreover, we found that TFF3-treated IEC-18 cells are resistant to anoikis, an anchorage-related apoptosis in epithelium. In addition, the stable expression of a mutant form of the endogenous NF-kappaB inhibitor (IkappaBalpha(mut)) in IEC-18 cells results in a significant attenuation of anti-anoikic effect of TFF3. Taken together, these data indicate that (1) TFF3 is an endogenous gastrointestinal peptide with anti-anoikic property; (2) TFF3 activates NF-kappaB in enterocytes; and (3) TFF3-induced resistance to anoikis in intestinal epithelial cells is mediated by a distinct signaling cascade linked to NF-kappaB. Furthermore, our study implicates NF-kappaB as an important regulator in survival pathway of intestinal epithelial cells.
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317
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Yu T, Bai Y, Dierich MP, Chen YH. Induction of high levels of epitope-specific antibodies by epitope/peptide candidate vaccines against human immunodeficiency virus type-1 (HIV-1). Microbiol Immunol 2000; 44:105-10. [PMID: 10803497 DOI: 10.1111/j.1348-0421.2000.tb01253.x] [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
To test the immunogenicity of GPGRAFY-epitope-based candidate vaccines, a peptide with four repetitive GPGRAFY epitopes, V3-P1 [C-(GPGRAFY)4], and a peptide (PND) of the principal neutralizing domain (V3 loop: amino acid 301-328: C-TRPNNNTRKSIRIQRGPGRAFYTIGKI) on gp120 were synthesized and covalently coupled to a carrier protein BSA. Immunization of BALB/c mice and New Zealand White Rabbits with these conjugate vaccines engendered strong antibody responses against the PND (mouse serum titer by 1:12,800-25,600; rabbit serum titer by 1:6,400-12,800). Interestingly, the V3-P1-BSA conjugates and the PND-BSA conjugates could induce high levels of GPGRAFY-epitope-specific antibodies in the mice and rabbits (mouse serum titer by 1:25,600; rabbit serum titer by 1:12,800-25,600), while a recombinant gp160 subunit vaccine induced a low level of GPGRAFY-epitope-specific antibodies (serum titer by 1:400-1,600 in mice and rabbits). To confirm the above results, GPGRAFY-epitope-specific antibodies were isolated from rabbit sera induced by V3-P1-BSA, PND-BSA conjugates and rgp160 vaccine. In fact, 23-38 and 13-22 microg epitope-specific antibodies per milliliter serum were isolated from rabbit sera induced by V3-P1-BSA and PND-BSA conjugate, respectively, while 1.34 microg epitope-specific antibodies per milliliter serum were identified in rabbit serum induced by rgp160 vaccine. In the control group, only 0.069 microg proteins per milliliter serum were found in pooled pre-immune serum (normal serum). These results from mouse and rabbit experiments indicate that epitope and peptide vaccines both induce high levels of GPGRAFY-epitope-specific antibodies in comparison with rgp160 subunit vaccine, suggesting that epitope/peptide vaccines may be a new strategy to induce protective activity.
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318
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van Besien K, Bartholomew A, Stock W, Peace D, Devine S, Sher D, Sosman J, Chen YH, Koshy M, Hoffman R. Fludarabine-based conditioning for allogeneic transplantation in adults with sickle cell disease. Bone Marrow Transplant 2000; 26:445-9. [PMID: 10982293 DOI: 10.1038/sj.bmt.1702518] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although allogeneic transplantation can be curative for patients with sickle cell disease, the toxicity of conditioning regimens has precluded its use in adults with significant end-organ damage. Newer conditioning regimens have been developed that are less toxic and that may broaden the applicability of allogeneic transplantation in this disorder. We report two adults with end-stage sickle cell disease, who underwent allogeneic transplantation from an HLA-identical sibling donor after conditioning with fludarabine/melphalan and ATG. Both patients had been extensively transfused and one had multiple RBC antibodies. One of the patients also had end-stage renal disease, and was dialysis dependent. Engraftment occurred promptly in both patients. Both achieved 100% donor chimerism and both were free of pain crises after transplant. The first patient died of a respiratory failure related to chronic graft-versus-host disease (GVHD) on day 335 after transplantation. The second patient developed severe gastro-intestinal GVHD and TTP and died on day 147 after transplantation. Conditioning with fludarabine/melphalan and ATG followed by allogeneic stem cell transplantation resulted in prompt and reliable engraftment in adults with end-stage sickle cell disease. The incidence of severe GVHD was unacceptably high and may be related to the ethnicity of the patients or to the inflammatory state associated with pre-existing sickle cell disease.
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319
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Xiao Y, Dong XN, Chen YH. Induction of monoclonal antibody with predefined ELNKWA epitope specificity by epitope vaccine. Hybridoma (Larchmt) 2000; 19:347-50. [PMID: 11001409 DOI: 10.1089/027245700429918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Since the hybridoma technique to produce monoclonal antibodies (MAbs) was discovered, thousands of MAbs with predefined protein specificity have been produced, and a natural or recombinant protein as antigen is necessary for inducing MAbs in the conventional hybridoma technique. To induce epitope-specific MAbs, we suggest an epitope vaccine as a new technique to induce MAbs with predefined epitope specificity. ELDKWA was identified as an important neutralizing epitope on HIV-1 gp41. The MAb 2F5, recognizing ELDKWA epitope, has shown broad neutralizing activity to many HIV strains, including primary isolates, but the mutant in ELNKWA epitope results in escape 2F5-based neutralization. To produce MAbs recognizing this mutated epitope for consideration of passive immunotherapy against the mutant bearing the ELNKWA epitope, MAbs with predefined ELNKWA epitope specificity were induced by synthetic epitope-peptide instead of a natural or recombinant gp41 bearing this epitope. Three MAbs were identified to recognize ELNKWA epitope on the synthetic epitope-peptide, and interestingly could bind the recombinant gp41 with ELDKWA epitope in an ELISA assay and immunoblotting analysis.
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320
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Tsai YJ, Lee RK, Lin SP, Chen YH. Identification of a novel platelet-derived growth factor-like gene, fallotein, in the human reproductive tract. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1492:196-202. [PMID: 11004490 DOI: 10.1016/s0167-4781(00)00066-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We isolated the cDNA of a novel platelet-derived growth factor-like gene from human endometrium. The gene was named fallotein; it was 3007 bases in length, and encoded a protein of 345 amino acids. Antiserum against the fallotein protein can recognize a specific protein in the fallopian tube, with a molecular size in accordance with the anticipated size of fallotein. Fallotein mRNA is expressed in two molecular sizes, 3.8 and 2.9 kb, with the former being more abundant. High expression of the gene was found in the prostate, testis, and uterus. A weaker expression signal was found in the spleen, thymus, and small intestine, but expression of fallotein in the colon and peripheral blood leukocytes was negligible.
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321
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Whitaker WR, Clare JJ, Powell AJ, Chen YH, Faull RL, Emson PC. Distribution of voltage-gated sodium channel alpha-subunit and beta-subunit mRNAs in human hippocampal formation, cortex, and cerebellum. J Comp Neurol 2000; 422:123-39. [PMID: 10842222 DOI: 10.1002/(sici)1096-9861(20000619)422:1<123::aid-cne8>3.0.co;2-x] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The distribution of mRNAs encoding voltage-gated sodium channel alpha subunits (I, II, III, and VI) and beta subunits (beta1 and beta2) was studied in selected regions of the human brain by Northern blot and in situ hybridisation experiments. Northern blot analysis showed that all regions studied exhibited heterogenous expression of sodium channel transcripts. In situ hybridisation experiments confirmed these findings and revealed a predominantly neuronal distribution. In the parahippocampal gyrus, subtypes II and VI and the beta-subunit mRNAs exhibited robust expression in the granule cells of the dentate gyrus and pyramidal cell layer of the hippocampus. Subtypes I and III showed moderate expression in granule cells and low expression in the pyramidal cell layer. Distinct expression patterns were also observed in the cortical layers of the middle frontal gyrus and in the entorhinal cortex. In particular, all subtypes exhibited higher levels of expression in cortical layers III, V, and VI compared with layers I and II. All subtypes were expressed in the granular layer of the cerebellum, whereas specific expression of subtypes I, VI, beta1, and beta2 mRNAs was observed in Purkinje cells. Subtypes I, VI, and beta1 mRNAs were expressed, at varying levels, in the pyramidal cells of the deep cerebellar nuclei. These data indicate that, as in rat, human brain sodium channel mRNAs have a distinct regional distribution, with individual cell types expressing different compliments of sodium channels. The differential distribution of sodium channel subtypes suggest that they have distinct roles that are likely to be of paramount importance in maintaining the functional heterogeneity of central nervous system neurons.
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322
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Tan XD, Chen YH, Liu QP, Gonzalez-Crussi F, Liu XL. Prostanoids mediate the protective effect of trefoil factor 3 in oxidant-induced intestinal epithelial cell injury: role of cyclooxygenase-2. J Cell Sci 2000; 113 ( Pt 12):2149-55. [PMID: 10825288 DOI: 10.1242/jcs.113.12.2149] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Trefoil factors are small peptides found in several mammalian tissues including gut, respiratory tract and brain. Their physiological function is not well understood. Among them, trefoil factor 3 (intestinal trefoil factor) is known to be cytoprotective in the gut. However, the molecular mechanism and secondary mediators of trefoil factor 3 action are not known. In the present study, we examined whether the cyclooxygenase pathway is involved in trefoil factor 3 action. We showed that trefoil factor 3 significantly induces the production of prostaglandin E(2) and prostaglandin I(2) in IEC-18 cells (an intestinal epithelial cell line) in a dose dependent manner. Western blot and immunohistochemistry revealed that trefoil factor 3 (2.5 microM) up-regulates the expression of cyclooxygenase-2 but not cyclooxygenase-1 in IEC-18 cells. Treating cells with trefoil factor 3 (10 microM) significantly attenuated reactive oxygen species-induced IEC-18 cell injury. This effect is blocked by NS-398 (10 microM), a selective cyclooxygenase-2 inhibitor. Moreover, we demonstrated that exogenously administered carbacyclin (1 microM, a stable analogue of prostaglandin I(2)) and/or prostaglandin E(2) (1 microM) caused a significant reduction of reactive oxygen species-induced cell injury, mimicking the effect of trefoil factor 3. In summary, our results indicate that trefoil factor 3 activates cyclooxygenase-2 in intestinal epithelium to produce prostaglandin I(2) and prostaglandin E(2), which function as survival factors and mediate the cytoprotective action of trefoil factor 3 against oxidant injury.
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323
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Hseu YC, Lu FJ, Engelking LR, Chen CL, Chen YH, Yang HL. Humic acid-induced echinocyte transformation in human erythrocytes: characterization of morphological changes and determination of the mechanism underlying damage. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2000; 60:215-230. [PMID: 10884168 DOI: 10.1080/009841000156493] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Blackfoot disease (BFD) is a peripheral arterial occlusive disease found among human inhabitants along the southwest coast of Taiwan. Well water used for drinking and cooking contains humic acid (HA), which may be a possible etiological factor. In this study, HA toxicity was investigated in human erythrocytes and was found to induce echinocytic formation. Morphological changes occurred in both a concentration- and time-dependent fashion. The presence of HA was also observed to facilitate the loading of erythrocytes with excess Ca(2+) (1 mM), which may have occurred following permeability changes in cell membranes, leading to echinocytic transformations. Sodium dodecyl sulfate (SDS) gel electrophoresis indicated that echinocyte formation was due to the oxidation of normal membrane proteins that were replaced by high-molecular-weight proteins. Humic acid also induced hemoglobin oxidation in erythrocytes. Data show that oxidative stress generated by HA as well as direct effects were exerted on the cytoskeleton of erythrocytes, and these may be significant factors in the etiology of BFD.
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324
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Zhao J, Chen YH, Kwan HS. Molecular cloning, characterization, and differential expression of a glucoamylase gene from the basidiomycetous fungus Lentinula edodes. Appl Environ Microbiol 2000; 66:2531-5. [PMID: 10831434 PMCID: PMC110576 DOI: 10.1128/aem.66.6.2531-2535.2000] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The complete nucleotide sequence of putative glucoamylase gene gla1 from the basidiomycetous fungus Lentinula edodes strain L54 is reported. The coding region of the genomic glucoamylase sequence, which is preceded by eukaryotic promoter elements CAAT and TATA, spans 2,076 bp. The gla1 gene sequence codes for a putative polypeptide of 571 amino acids and is interrupted by seven introns. The open reading frame sequence of the gla1 gene shows strong homology with those of other fungal glucoamylase genes and encodes a protein with an N-terminal catalytic domain and a C-terminal starch-binding domain. The similarity between the Gla1 protein and other fungal glucoamylases is from 45 to 61%, with the region of highest conservation found in catalytic domains and starch-binding domains. We compared the kinetics of glucoamylase activity and levels of gene expression in L. edodes strain L54 grown on different carbon sources (glucose, starch, cellulose, and potato extract) and in various developmental stages (mycelium growth, primordium appearance, and fruiting body formation). Quantitative reverse transcription PCR utilizing pairs of primers specific for gla1 gene expression shows that expression of gla1 was induced by starch and increased during the process of fruiting body formation, which indicates that glucoamylases may play an important role in the morphogenesis of the basidiomycetous fungus.
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MESH Headings
- Amino Acid Sequence
- Cloning, Molecular
- Culture Media
- Gene Expression Regulation, Fungal
- Genes, Fungal
- Genomic Library
- Glucan 1,4-alpha-Glucosidase/chemistry
- Glucan 1,4-alpha-Glucosidase/genetics
- Glucan 1,4-alpha-Glucosidase/metabolism
- Lentinula/enzymology
- Lentinula/genetics
- Lentinula/growth & development
- Molecular Sequence Data
- Promoter Regions, Genetic
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Sequence Analysis, DNA
- Terminator Regions, Genetic
- Transcription, Genetic
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325
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Chen YH, Du GH, Zhang JT. Salvianolic acid B protects brain against injuries caused by ischemia-reperfusion in rats. Acta Pharmacol Sin 2000; 21:463-6. [PMID: 11324448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
AIM To study the protective effects of salvianolic acid B (Sal B) against the ischemia-reperfusion induced rat brain injury. METHODS Focal cerebral ischemia-reperfusion model in rats was employed to study the protective effects of Sal B. The behavioural tests were used to evaluate the damage to the central nervous system. Spectrophotometric assay methods were used to measure the activity of superoxide dismutase (SOD), contents of reduced glutathione (GSH), malondialdehyde (MDA), adenosine 5-triphosphorate (ATP), and lactate acid (LA) in experimental rats' brain homogenate. RESULTS Focal cerebral ischemia-reperfusion resulted in abnormal behavior which could be alleviated by Sal B 10 mg.kg-1 i.v., and nimodipine (Nim) 4 mg.kg-1 i.p. At the same time, Sal B 10 mg.kg-1 and Nim 4 mg.kg-1 could inhibit the decrease in SOD, GSH, and ATP levels and the increase in MDA and LA levels caused by ischemia-reperfusion in brain. CONCLUSION Sal B showed a protective action against the ischemia-reperfusion induced injury in rat brain by reducing lipid peroxides, scavenging free radicals and improving the energy metabolism.
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