626
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Yang Y, Zhang C, Sheng W, Pan S, Wu D, Jiang F. [Correlation between electroretinographic findings, clinical phenotypic and genotypic analysis in Duchenne and Becker muscular dystrophy]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 2001; 18:32-4. [PMID: 11172639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
OBJECTIVE To explore the relationship between electrophysiological changes, clinical phenotype and genotype in Duchenne and Becker muscular dystrophy(DMD/BMD), to address the expression and roles of dystrophin and its isoforms on the retina, and to inquire into the molecular mechanism of the abnormal electroretinogram(ERG) on DMD/BMD patients with different genotype. METHODS Gene deletions were screened by multiplex DNA amplification with eleven primers on twenty-two consecutive patients with DMD and BMD, and then, the ERG was tested according to international ERG standard. RESULTS ERG phenotype was associated with the site of DMD gene defects rather than the severity of the phenotype. Patients with deletion in the central region of the gene had more severe changes in the scotopic ERG as compared to those with gene non-deletion. CONCLUSION The ERG genotype-phenotype correlation suggests that DP260 may play the most important role in the retinal neurotransmission.
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627
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Gandhi OP, Kang G, Wu D, Lazzi G. Currents induced in anatomic models of the human for uniform and nonuniform power frequency magnetic fields. Bioelectromagnetics 2001; 22:112-21. [PMID: 11180257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
We have used the quasi-static impedance method to calculate the currents induced in the nominal 2 x 2 x 3 and 6 mm resolution anatomically based models of the human body for exposure to magnetic fields at 60 Hz. Uniform magnetic fields of various orientations and magnitudes 1 or 0.417 mT suggested in the ACGIH and ICNIRP safety guidelines are used to calculate induced electric fields or current densities for the various glands and organs of the body including the pineal gland. The maximum 1 cm(2) area-averaged induced current densities for the central nervous system tissues, such as the brain and the spinal cord, were within the reference level of 10 mA/m(2) as suggested in the ICNIRP guidelines for magnetic fields (0.417 mT at 60 Hz). Tissue conductivities were found to play an important role and higher assumed tissue conductivities gave higher induced current densities. We have also determined the induced current density distributions for nonuniform magnetic fields associated with two commonly used electrical appliances, namely a hair dryer and a hair clipper. Because of considerably higher magnetic fields for the latter device, higher induced electric fields and current densities were calculated.
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628
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Bhardwaj G, Murdoch B, Wu D, Baker DP, Williams KP, Chadwick K, Ling LE, Karanu FN, Bhatia M. Sonic hedgehog induces the proliferation of primitive human hematopoietic cells via BMP regulation. Nat Immunol 2001; 2:172-80. [PMID: 11175816 DOI: 10.1038/84282] [Citation(s) in RCA: 446] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A pool of stem cells that arise from the mesoderm during embryogenesis initiates hematopoiesis. However, factors that regulate the expansion of blood stem cells are poorly understood. We show here that cytokine-induced proliferation of primitive human hematopoietic cells could be inhibited with antibodies to hedgehog (Hh). Conversely, Sonic hedgehog (Shh) treatment induced the expansion of pluripotent human hematopoietic repopulating cells detected in immunodeficient mice. Noggin, a specific inhibitor of bone morphogenetic protein 4 (BMP-4), was capable of inhibiting Shh-induced proliferation in a similar manner to anti-Hh; however, anti-Hh had no effect on BMP-4-induced proliferation. Our study shows that Shh functions as a regulator of primitive hematopoietic cells via mechanisms that are dependent on downstream BMP signals.
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629
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Song C, Hu CD, Masago M, Kariyai K, Yamawaki-Kataoka Y, Shibatohge M, Wu D, Satoh T, Kataoka T. Regulation of a novel human phospholipase C, PLCepsilon, through membrane targeting by Ras. J Biol Chem 2001; 276:2752-7. [PMID: 11022048 DOI: 10.1074/jbc.m008324200] [Citation(s) in RCA: 264] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Phosphoinositide-specific phospholipase C (PI-PLC) plays a pivotal role in regulation of intracellular signal transduction from various receptor molecules. More than 10 members of human PI-PLC isoforms have been identified and classified into three classes beta, gamma, and delta, which are regulated by distinct mechanisms. Here we report identification of a novel class of human PI-PLC, named PLCepsilon, which is characterized by the presence of a Ras-associating domain at its C terminus and a CDC25-like domain at its N terminus. The Ras-associating domain of PLCepsilon specifically binds to the GTP-bound forms of Ha-Ras and Rap1A. The dissociation constant for Ha-Ras is estimated to be approximately 40 nm, comparable with those of other Ras effectors. Co-expression of an activated Ha-Ras mutant with PLCepsilon induces its translocation from the cytosol to the plasma membrane. Upon stimulation with epidermal growth factor, similar translocation of ectopically expressed PLCepsilon is observed, which is inhibited by co-expression of dominant-negative Ha-Ras. Furthermore, using a liposome-based reconstitution assay, it is shown that the phosphatidylinositol 4,5-bisphosphate-hydrolyzing activity of PLCepsilon is stimulated in vitro by Ha-Ras in a GTP-dependent manner. These results indicate that Ras directly regulates phosphoinositide breakdown through membrane targeting of PLCepsilon.
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630
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Qu W, Xiao B, Wu D. [The effect of alcohol on c-fos gene expression in rat embryo neuroglial]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2001; 35:55-6. [PMID: 11860963] [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 This paper is aimed to explore the mechanisms of brain development abnormality induced by alcohol. METHODS Astrocytes and oligodendrocytes of 19-day rat embryo were exploited and cultured in vitro, and alcohol and its metabolite product (acetaldehyde) were added to DMEMF(12) medium. After different exposure times, c-fos expression of astrocytes and oligodendrocytes was measured by the immunocytochemistry technique. RESULTS Changes in c-fos gene expression induced by alcohol and acetaldehyde was time and dose dependent. After 1 hr exposure, alcohol and acetaldehyde affected c-fos gene expression in two kinds of neuralglia. C-fos positive expression reached peak value after 2 hr, but recovered after 72 hr and showed special time phase expression. CONCLUSIONS Alcohol and acetaldehyde cause abnormal increase of c-fos gene expression in astrocytes and oligodendrocytes. This abnormal expression may play an important role in abnormal brain development induced by alcohol.
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631
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Marí M, Wu D, Nieto N, Cederbaum AI. CYP2E1-dependent toxicity and up-regulation of antioxidant genes. J Biomed Sci 2001; 8:52-8. [PMID: 11173976 DOI: 10.1007/bf02255971] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Induction of cytochrome P450 2E1 (CYP2E1) by ethanol appears to be one of the central pathways by which ethanol generates a state of oxidative stress. Glutathione (GSH) is critical in preserving the proper cellular redox balance and for its role as a cellular protectant. The goal of the present study was to characterize the GSH homeostasis in human hepatocarcinoma cells (HepG2-E47 cells) that overexpress CYP2E1. Toxicity in the E47 cells was markedly enhanced after GSH depletion by buthionine sulfoximine (BSO) treatment. The antioxidant trolox partially prevented the apoptosis and necrosis, while diallylsulfide, a CYP2E1 inhibitor, was fully protective. Damage to mitochondria appears to play a role in the CYP2E1- and BSO-dependent toxicity. CYP2E1-overexpressing cells showed increases in total GSH levels, GSH synthetic rate and in gamma-glutamylcysteine synthetase (GCS) mRNA. This GCS increase was due to transcriptional activation of the GCS gene and could be blocked by certain antioxidants. Activity, protein and mRNA levels for other antioxidants such as catalase, alpha- and microsomal glutathione transferases were also increased in the E47 cells. Up-regulation of these antioxidant genes may reflect an adaptive mechanism to remove CYP2E1-derived oxidants. These oxidants are diffusable and were able to elevate collagen type I protein in a co-culture system consisting of the E47 cells + rat hepatic stellate cells. Such interactions between CYP2E1, mitochondria and altered GSH homeostasis, and elevation of collagen levels, may play a role in alcohol-induced liver injury.
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632
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633
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Romoser VA, Graves TK, Wu D, Jiang H, Hinkle PM. Calcium responses to thyrotropin-releasing hormone, gonadotropin-releasing hormone and somatostatin in phospholipase css3 knockout mice. Mol Endocrinol 2001; 15:125-35. [PMID: 11145744 DOI: 10.1210/mend.15.1.0588] [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: 11/19/2022] Open
Abstract
These studies examined the importance of phospholipase Cbeta (PLCbeta) in the calcium responses of pituitary cells using PLCbeta3 knockout mice. Pituitary tissue from wild-type mice contained PLCbeta1 and PLCbeta3 but not PLCbeta2 or PLCbeta4. Both Galphaq/11 and Gbetagamma can activate PLCbeta3, whereas only Galphaq/11 activates PLCss1 effectively. In knockout mice, PLCbeta3 was absent, PLCbeta1 was not up-regulated, and PLCbeta2 and PLCbeta4 were not expressed. Since somatostatin inhibited influx of extracellular calcium in pituitary cells from wild-type and PLCbeta3 knockout mice, the somatostatin signal pathway was intact. However, somatostatin failed to increase intracellular calcium in pituitary cells from either wild-type or knockout mice under a variety of conditions, indicating that it did not stimulate PLCbeta3. In contrast, somatostatin increased intracellular calcium in aortic smooth muscle cells from wild-type mice, although it evoked no calcium response in cells from PLCbeta3 knockout animals These results show that somatostatin, like other Gi/Go-linked hormones, can stimulate a calcium transient by activating PLCbeta3 through Gbetagamma, but this response does not normally occur in pituitary cells. The densities of Gi and Go, as well as the relative concentrations of PLCbeta1 and PLCbeta3, were similar in cells that responded to somatostatin with an increase in calcium and pituitary cells. Calcium responses to 1 nM and 1 microM TRH and GnRH were identical in pituitary cells from wild-type and PLCbeta3 knockout mice, as were responses to other Gq-linked agonists. These results show that in pituitary cells, PLCbeta1 is sufficient to transmit signals from Gq-coupled hormones, whereas PLCbeta3 is required for the calcium-mobilizing actions of somatostatin observed in smooth muscle cells.
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634
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Rosu-Myles M, Gallacher L, Murdoch B, Hess DA, Keeney M, Kelvin D, Dale L, Ferguson SS, Wu D, Fellows F, Bhatia M. The human hematopoietic stem cell compartment is heterogeneous for CXCR4 expression. Proc Natl Acad Sci U S A 2000; 97:14626-31. [PMID: 11121064 PMCID: PMC18969 DOI: 10.1073/pnas.97.26.14626] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The chemokine stromal derived factor-1alpha (SDF-1alpha) has been implicated recently in the chemotaxis of primitive human hematopoietic cells, suggesting that pluripotent human stem cells express the SDF-1alpha receptor, CXCR4. By using flow cytometry and confocal microscopy, we have identified and isolated primitive subsets of human CXCR4(+) and CXCR4(-) cells. Distinctions in the progenitor content and response to SDF-1alpha in vitro indicate that CXCR4(+) and CXCR4(-) cells represent discrete populations of primitive blood cells. The i.v. transplantation of these subfractions into immune-deficient mice established that both possess comparable engraftment capacity in vivo. Human myeloid, lymphoid, and primitive CD34(+) CXCR4(+) cells were present in chimeric animals transplanted with either subset, indicating that CXCR4(+) and CXCR4(-) stem cells have equivalent proliferative and differentiative abilities. Our study indicates that the human stem cell compartment is heterogeneous for CXCR4 expression, suggesting that the relationship between CXCR4 expression and stem cell repopulating function is not obligatory.
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635
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Theologis A, Ecker JR, Palm CJ, Federspiel NA, Kaul S, White O, Alonso J, Altafi H, Araujo R, Bowman CL, Brooks SY, Buehler E, Chan A, Chao Q, Chen H, Cheuk RF, Chin CW, Chung MK, Conn L, Conway AB, Conway AR, Creasy TH, Dewar K, Dunn P, Etgu P, Feldblyum TV, Feng J, Fong B, Fujii CY, Gill JE, Goldsmith AD, Haas B, Hansen NF, Hughes B, Huizar L, Hunter JL, Jenkins J, Johnson-Hopson C, Khan S, Khaykin E, Kim CJ, Koo HL, Kremenetskaia I, Kurtz DB, Kwan A, Lam B, Langin-Hooper S, Lee A, Lee JM, Lenz CA, Li JH, Li Y, Lin X, Liu SX, Liu ZA, Luros JS, Maiti R, Marziali A, Militscher J, Miranda M, Nguyen M, Nierman WC, Osborne BI, Pai G, Peterson J, Pham PK, Rizzo M, Rooney T, Rowley D, Sakano H, Salzberg SL, Schwartz JR, Shinn P, Southwick AM, Sun H, Tallon LJ, Tambunga G, Toriumi MJ, Town CD, Utterback T, Van Aken S, Vaysberg M, Vysotskaia VS, Walker M, Wu D, Yu G, Fraser CM, Venter JC, Davis RW. Sequence and analysis of chromosome 1 of the plant Arabidopsis thaliana. Nature 2000; 408:816-20. [PMID: 11130712 DOI: 10.1038/35048500] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The genome of the flowering plant Arabidopsis thaliana has five chromosomes. Here we report the sequence of the largest, chromosome 1, in two contigs of around 14.2 and 14.6 megabases. The contigs extend from the telomeres to the centromeric borders, regions rich in transposons, retrotransposons and repetitive elements such as the 180-base-pair repeat. The chromosome represents 25% of the genome and contains about 6,850 open reading frames, 236 transfer RNAs (tRNAs) and 12 small nuclear RNAs. There are two clusters of tRNA genes at different places on the chromosome. One consists of 27 tRNA(Pro) genes and the other contains 27 tandem repeats of tRNA(Tyr)-tRNA(Tyr)-tRNA(Ser) genes. Chromosome 1 contains about 300 gene families with clustered duplications. There are also many repeat elements, representing 8% of the sequence.
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636
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Salanoubat M, Lemcke K, Rieger M, Ansorge W, Unseld M, Fartmann B, Valle G, Blöcker H, Perez-Alonso M, Obermaier B, Delseny M, Boutry M, Grivell LA, Mache R, Puigdomènech P, De Simone V, Choisne N, Artiguenave F, Robert C, Brottier P, Wincker P, Cattolico L, Weissenbach J, Saurin W, Quétier F, Schäfer M, Müller-Auer S, Gabel C, Fuchs M, Benes V, Wurmbach E, Drzonek H, Erfle H, Jordan N, Bangert S, Wiedelmann R, Kranz H, Voss H, Holland R, Brandt P, Nyakatura G, Vezzi A, D'Angelo M, Pallavicini A, Toppo S, Simionati B, Conrad A, Hornischer K, Kauer G, Löhnert TH, Nordsiek G, Reichelt J, Scharfe M, Schön O, Bargues M, Terol J, Climent J, Navarro P, Collado C, Perez-Perez A, Ottenwälder B, Duchemin D, Cooke R, Laudie M, Berger-Llauro C, Purnelle B, Masuy D, de Haan M, Maarse AC, Alcaraz JP, Cottet A, Casacuberta E, Monfort A, Argiriou A, flores M, Liguori R, Vitale D, Mannhaupt G, Haase D, Schoof H, Rudd S, Zaccaria P, Mewes HW, Mayer KF, Kaul S, Town CD, Koo HL, Tallon LJ, Jenkins J, Rooney T, Rizzo M, Walts A, Utterback T, Fujii CY, Shea TP, Creasy TH, Haas B, Maiti R, Wu D, Peterson J, Van Aken S, Pai G, Militscher J, Sellers P, Gill JE, Feldblyum TV, Preuss D, Lin X, Nierman WC, Salzberg SL, White O, Venter JC, Fraser CM, Kaneko T, Nakamura Y, Sato S, Kato T, Asamizu E, Sasamoto S, Kimura T, Idesawa K, Kawashima K, Kishida Y, Kiyokawa C, Kohara M, Matsumoto M, Matsuno A, Muraki A, Nakayama S, Nakazaki N, Shinpo S, Takeuchi C, Wada T, Watanabe A, Yamada M, Yasuda M, Tabata S. Sequence and analysis of chromosome 3 of the plant Arabidopsis thaliana. Nature 2000; 408:820-2. [PMID: 11130713 DOI: 10.1038/35048706] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Arabidopsis thaliana is an important model system for plant biologists. In 1996 an international collaboration (the Arabidopsis Genome Initiative) was formed to sequence the whole genome of Arabidopsis and in 1999 the sequence of the first two chromosomes was reported. The sequence of the last three chromosomes and an analysis of the whole genome are reported in this issue. Here we present the sequence of chromosome 3, organized into four sequence segments (contigs). The two largest (13.5 and 9.2 Mb) correspond to the top (long) and the bottom (short) arms of chromosome 3, and the two small contigs are located in the genetically defined centromere. This chromosome encodes 5,220 of the roughly 25,500 predicted protein-coding genes in the genome. About 20% of the predicted proteins have significant homology to proteins in eukaryotic genomes for which the complete sequence is available, pointing to important conserved cellular functions among eukaryotes.
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637
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Wu D, Xu X, Ren B, Cao Z, Shi P, Tian Z. [A quantum chemical study of pi-back-donation bond and Raman intensity of 1 sigma + electronic state of Pt-CO molecule]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2000; 20:793-796. [PMID: 12938471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The Raman spectroscopic properties of Pt-CO molecule have been investigated based on the electronic state 1 sigma + determined by the HF and B3LYP methods. The result shows that the calculated stretching vibrational frequencies of the Pt-C and C-O bonds depend on the method and the basis sets used. It indicates that it is important to adopt an appropriate method to describe pi-donation and pi-back-donation bond. The result of the differential Raman scattering cross section for the stretching vibrations of the Pt-C and C-O bond shows that the latter is significantly larger value compared to the former.
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638
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Hsieh IC, Chang HJ, Chern MS, Hung KC, Lin FC, Wu D. Benefits of late coronary artery stenting in patients with acute myocardial infarction with and without thrombolytic therapy. CHANG GUNG MEDICAL JOURNAL 2000; 23:738-46. [PMID: 11416894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
BACKGROUND There are no added benefits when balloon angioplasty is conducted in conjunction with thrombolytic therapy in patients with acute myocardial infarction. The purpose of this study was to determine whether or not thrombolysis has an impact on the outcome of late coronary artery stenting following acute myocardial infarction. METHODS The outcome of late coronary artery stenting in the infarct-related artery following acute infarction was compared in patients with (68 patients, group A) and without (118 patients, group B) prior thrombolytic therapy. RESULTS The baseline characteristics were similar in the 2 groups except that total occlusion of the infarct-related artery was more common in group B. The angiographic characteristics of the target lesion were similar in the 2 groups; the procedural success rate was 98% in both groups. There was no subacute thrombosis or other complications in either group. The 6-month follow-up coronary angiography and the restenosis rate was 18% in both groups; the reocclusion rate was 2% in group A and 4% in group B. The increment of the left ventricular ejection fraction was similar in both groups (6% versus 7%). During a follow-up duration of 18 +/- 3 months, the mortality rate was 3% versus 2%, reinfarction 0% versus 1%, recurrent angina 6% versus 4%, and target lesion revascularization by angioplasty 13% versus 13% in group A and B patients, respectively. CONCLUSION The outcome of late coronary artery stenting following acute myocardial infarction in patients with and without prior thrombolytic therapy was comparable. Significant improvement of left ventricular function was noted in both groups.
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639
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Lian W, Chen G, Wu D, Brown CK, Madauss K, Hersh LB, Rodgers DW. Crystallization and preliminary analysis of neurolysin. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2000; 56:1644-6. [PMID: 11092934 DOI: 10.1107/s0907444900012683] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2000] [Accepted: 09/13/2000] [Indexed: 11/10/2022]
Abstract
Neuropeptidases inactivate or modify the activity of peptide neurotransmitters and neurohormones. The neuropeptidase neurolysin acts only on short peptides and accepts a variety of cleavage-site sequences. Structures of the enzyme and enzyme-substrate complexes will help to determine the mechanisms of substrate selectivity used by this enzyme. Crystals of recombinant neurolysin have been grown in the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 157.8, b = 88.0, c = 58.4 A. Data have been collected to 2.3 A at 110 K with observed diffraction to 1.8 A. Circular dichroism measurements suggest that the enzyme is primarily alpha-helical, with little beta-strand secondary structure. Sequence-based secondary-structure prediction supports this conclusion.
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640
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Wong HC, Mao J, Nguyen JT, Srinivas S, Zhang W, Liu B, Li L, Wu D, Zheng J. Structural basis of the recognition of the dishevelled DEP domain in the Wnt signaling pathway. NATURE STRUCTURAL BIOLOGY 2000; 7:1178-84. [PMID: 11101902 PMCID: PMC4381838 DOI: 10.1038/82047] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The DEP domain of Dishevelled (Dvl) proteins transduces signals to effector proteins downstream of Dvl in the Wnt pathway. Here we report that DEP-containing mutants inhibit Wnt-induced, but not Dvl-induced, activation of the transcription factor Lef-1. This inhibitory effect is weakened by a K434M mutation. Nuclear magnetic resonance spectroscopy revealed that the DEP domain of mouse Dvl1 comprises a three-helix bundle, a beta-hairpin 'arm' and two short beta-strands at the C-terminal region. Lys 434 is located at the tip of the beta-hairpin 'arm'. Based on our findings, we conclude that DEP interacts with regulators upstream of Dvl via a strong electric dipole on the molecule's surface created by Lys 434, Asp 445 and Asp 448; the electric dipole and the putative membrane binding site are at two different locations.
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641
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Xia W, Meng X, Xing X, Hu Y, Liu H, Zhou X, Qiu G, Yang X, Shen V, Wu D, Dempster D, Lindsay R. [Effects of 1 alpha(OH)D3 on trabecular and cortical bone in ovariectomized rats]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 2000; 22:543-7. [PMID: 12903400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To study the pharmaceutical effects of 1 alpha(OH)D3 on trabecular and cortical bone in ovariectomized (OVX) rats. METHODS 41 female Wistar rats of six months old were randomly divided into 5 groups: (1) Baseline control; (2) Sham control; (3) 6 weeks after OVX (OVXb); (4) 14 weeks after OVX (OVXe); (5) OVX + 0.1 microgram/(kg.d) 1 alpha(OH)D3 (O + VD), treatment started 6 weeks after OVX and lasted 8 weeks. Histomorphometry analysis of tibia, peripheral quantitative computed tomography (pQCT) scanning of femur, bone biomechanical test and serum and urinary biochemical parameters were determined. RESULTS The levels of bone turnover indexes increased in OVX rats, OVX also resulted in reducing of trabecular, bone mass and biomechanical properties. The ratio of urinary deoxypyridinoline crosslink/creatinine was decreased by 67.0% in O + VD group compared with OVXe group 67.0% [(43.50 +/- 11.20) nmol.L-1/mmol.L-1 vs(131.80 +/- 14.90) nmol.L-1/mmol.L-1, P < 0.01]. Percent trabecular area (Cn-BV/TV) was increased by 89.8% in O + VD group compared with OVXe group (11.03 +/- 0.73 vs 5.81 +/- 1.29, P < 0.05). Trabecular bone mineral content and density were increased by 77.3% and 91.3% compared with OVXe respectively (P < 0.05). Although cancellous maximal load and stiffness increased in O + VD group, but no statistical significance. 1 alpha(OH)D3 also enhanced polar moment of inertia (PMI) and maximal load of cortical bone in femur compared with OVXe (23.70 +/- 1.63 vs 18.23 +/- 1.41, P < 0.01 and 171.69 +/- 9.92 vs 147.58 +/- 11.29, P < 0.05 respectively). CONCLUSION 1 alpha(OH)D3 inhibited the higher bone turnover induced by OVX, increased trabecular bone in proximal tibia and bone mass in distal femur. 1 alpha(OH)D3 also improved the mechanical properties of cortical bone in femur.
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642
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Wu D, Stassen JM, Seidler R, Doods H. Effects of BIIB513 on ischemia-induced arrhythmias and myocardial infarction in anesthetized rats. Basic Res Cardiol 2000; 95:449-56. [PMID: 11192365 DOI: 10.1007/s003950070020] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Na+/H+ exchange (NHE) plays an important role in the regulation of the intracellular pH (pHi) and in cardiac cell injury induced by ischemia and reperfusion. In the present study, we investigated the effects of BIIB513, a selective NHE-1 inhibitor on myocardial ischemia induced arrhythmias and myocardial infarction, provoked by 30 minutes of left main coronary artery occlusion followed by 2 hours of reperfusion in an anesthetized rat model. Intravenous administration of BIIB513 (0.01-3.0 mg/kg) did not induce changes in blood pressure or heart rate. BIIB513 (0.01, 0.1, 0.3, 1.0, 3.0 mg/kg) given prior to the coronary artery occlusion dose-dependently reduced ventricular premature beats, ventricular tachycardia, and a complete suppression of ventricular fibrillation down to the dose of 0.1 mg/kg. BIIB513 (0.01, 0.1, 0.3, 1.0, 3.0 mg/kg) given prior to the coronary artery occlusion dose-dependently reduced the infarct size with an ED50 value of 0.16 mg/kg. BIIB513 (1.0 mg/kg) given prior to reperfusion also reduced infarct size by 47.3 +/- 13.1%. The reduction in infarct size was accompanied by a decrease in circulating levels of creatine phosphokinase (CPK). In conclusion, the present study demonstrates the cardioprotective ability of NHE-1 inhibition during myocardial ischemia and reperfusion by reducing serious ventricular arrhythmias and myocardial infarct size in anesthetized rats.
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643
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Chen X, Wu D, Wang G, Ren H. [Effect of elevated CO2 concentration on photosynthesis and antioxidative enzyme activities of wheat plant grown under drought condition]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2000; 11:881-4. [PMID: 11767564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The photosynthesis and antioxidative enzyme activities of wheat plants grown in two open-top chambers with CO2 concentrations of 350 mumol.mol-1 and 700 mumol.mol-1 were examined under drought stress. The result showed that elevated CO2 concentration obviously enhanced the photosynthesis, stomatal resistance and water use efficiency, but decreased the transpiration of wheat. Doubled CO2 concentration significantly increased the activities of CAT, POD and SOD, which enhanced the abilities of antioxidative defence and drought tolerance.
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644
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Liu HY, Wu D, Lu GW. [Effect of excite amino acid on tolerance exposed to hypoxic]. ZHONGGUO YING YONG SHENG LI XUE ZA ZHI = ZHONGGUO YINGYONG SHENGLIXUE ZAZHI = CHINESE JOURNAL OF APPLIED PHYSIOLOGY 2000; 16:342, 346. [PMID: 11236696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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645
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Abstract
We conducted a molecular epidemiologic study in rural China to investigate the association of the cytochrome P450 2D6 (CYP2D6) and glutathione S-transferase Mu (GSTM1) polymorphisms with dysmenorrhea. This report includes 435 subjects, 129 with and 306 without any history of dysmenorrhea, who did not smoke or drink alcohol. We obtained information on dysmenorrhea and major covariates by questionnaire interview. We used categorical methods and logistic regression models to evaluate the individual and combined associations of CYP2D6 and GSTM1 polymorphisms with dysmenorrhea and its subgroups, occasional (N = 70) and recurrent (N = 59), with adjustment for age, education, occupation, passive smoke exposure, age of menarche, parity, contraceptive method, height, and body mass index. Both variant CYP2D6 and GSTM1 genotypes were associated with increased risk of recurrent dysmenorrhea [for CYP2D6, odds ratio (OR) = 1.7 and 95% confidence interval (95% CI) = 0.9-3.1; for GSTM1, OR = 1.8 and 95% CI = 1.0-3.4). There was no appreciable association between these variant genotypes and occasional dysmenorrhea. When both the CYP2D6 and GSTM1 genotypes were considered together, the highest risk of recurrent dysmenorrhea was found among women with variant genotypes in both CYP2D6 and GSTM1 (OR = 3.1; 95% CI = 1.2-8.0). This study provides evidence of genetic susceptibility to recurrent dysmenorrhea.
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646
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He B, Wu D. Laplacian electrocardiography. Crit Rev Biomed Eng 2000; 27:285-338. [PMID: 10864282] [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]
Abstract
This article reviews the recent development in Laplacian electrocardiography. The Laplacian electrocardiogram was proposed in the early 1990s as an alternative for mapping regional cardiac electrical activity. Considerable progress has been made in the field during the last 5 years on this emerging technique. This article attempts to cover both the basic concepts and theory for general readers in biomedical engineering, and state-of-the-art developments in forward and inverse problems of Laplacian electrocardiography, as well as Laplacian ECG mapping in an experimental setting for researchers working in the field of cardiac mapping. The article also addresses controversies regarding the feasibility of experimentally obtaining the Laplacian electrocardiogram in human subjects. The work reviewed in this article suggests that Laplacian electrocardiography merits further investigation and promises to provide an important alternative means of assessing noninvasively cardiac electrical activity.
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647
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Wu D, Aranovich GL, Donohue MD. Adsorption of Amphiphilic Dimers at Surfaces. J Colloid Interface Sci 2000; 230:281-290. [PMID: 11017734 DOI: 10.1006/jcis.2000.7059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adsorption of amphiphilic dimers is analyzed in the framework of density functional Ono-Kondo theory. There are three configurations for dimers absorbed at a surface: one parallel to the surface and two perpendicular to the surface (AB and BA, with A or B touching the surface, respectively). Densities of molecules in each configuration are calculated from density functional theory and compared to Monte Carlo simulation data. There is good agreement between theory and simulations. It is shown that the parallel configuration is preferred over the perpendicular configuration, except when there are very strong asymmetries in intermolecular forces. In most cases, the parallel configuration is even preferred over the combination of the two perpendicular configurations. Copyright 2000 Academic Press.
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648
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Han SN, Meydani M, Wu D, Bender BS, Smith DE, Viña J, Cao G, Prior RL, Meydani SN. Effect of long-term dietary antioxidant supplementation on influenza virus infection. J Gerontol A Biol Sci Med Sci 2000; 55:B496-503. [PMID: 11034223 DOI: 10.1093/gerona/55.10.b496] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This study compared the effect of vitamin E on the course of influenza infection with that of other antioxidants. (In a previous study we showed that short-term vitamin E supplementation significantly decreased pulmonary viral titer in influenza-infected old mice). Eighteen-month-old C57BL/6NCrlBR mice were fed one of the following semisynthetic diets for 6 months: control, vitamin E supplemented, glutathione supplemented, vitamin E and glutathione supplemented, melatonin supplemented, or strawberry extract supplemented. After influenza virus challenge, mice fed vitamin E-supplemented diet had significantly lower pulmonary viral titers compared to those fed the control diet (10(2.6) vs 10(4.0), p < .05) and were able to maintain their body weight after infection (1.8+/-0.9 g weight loss/5 days postinfection in vitamin E group vs 6.8+/-1.4 g weight loss/5 days postinfection in control group, p < .05). Other antioxidants did not have a significant effect on viral titer or weight loss. There was a significant inverse correlation of weight loss with food intake (r = -.96, p < .01), indicating that the observed weight changes were mainly due to decreased food intake. Pulmonary interleukin (IL)-6, IL-1beta, and tumor necrosis factor (TNF)-alpha levels increased significantly postinfection. The vitamin E group had lower lung IL-6 and TNF-alpha levels following infection compared to the control group. In addition, there was a significant positive correlation between weight loss and lung IL-6 (r = .77, p < .01) and TNF-alpha (r = .68, p < .01) levels. Because IL-6 and TNF-alpha have been shown to contribute to the anorexic effect of infectious agents, the prevention of weight loss by vitamin E might be due to its reduced production of IL-6 and TNF-alpha following infection. Thus, among the antioxidants tested, only vitamin E was effective in reducing pulmonary viral titers and preventing an influenza-mediated decrease in food intake and weight loss. Other dietary antioxidant supplementations that reduced one or more measures of oxidative stress (4-hydroxynonenal, malondialdehyde, and hydrogen peroxide) did not have an effect on viral titer, which suggests that, in addition to its antioxidant activity, other mechanisms might be involved in vitamin E's beneficial effect on lowering viral titer and preventing weight loss.
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649
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Bugianesi R, Serafini M, Simone F, Wu D, Meydani S, Ferro-Luzzi A, Azzini E, Maiani G. High-performance liquid chromatography with coulometric electrode array detector for the determination of quercetin levels in cells of the immune system. Anal Biochem 2000; 284:296-300. [PMID: 10964412 DOI: 10.1006/abio.2000.4697] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There is mounting evidence emphasizing the importance of intracellular antioxidant levels for maintenance of the immune function. The flavonoid quercetin, a natural antioxidant, has been shown to modulate enzymes involved in the regulation of the inflammatory response. However, up to now, there have been no studies describing quercetin levels in cells of the immune system. A gradient reversed-phase HPLC technique to identify and quantify intracellular levels of quercetin and its application in mice splenocytes are described. Mobile phases were a 0.01 M sodium phosphate monobasic solution adjusted to pH 2.8 with 85% orthophosphoric acid (buffer, Solvent A) and methanol (Solvent B) with a flow rate of 1 ml/min. An eight-channel coulometric electrode array detector was used. In vitro supplementation with increasing concentration of quercetin (25, 50, and 100 microM) raises intracellular quercetin levels in a dose-dependent manner. The method has the required features of specificity and sensitivity for monitoring quercetin uptake in cells of the immune system.
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650
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Hashimoto K, Watanabe M, Kurihara H, Offermanns S, Jiang H, Wu Y, Jun K, Shin HS, Inoue Y, Wu D, Simon MI, Kano M. Climbing fiber synapse elimination during postnatal cerebellar development requires signal transduction involving G alpha q and phospholipase C beta 4. PROGRESS IN BRAIN RESEARCH 2000; 124:31-48. [PMID: 10943115 DOI: 10.1016/s0079-6123(00)24006-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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