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Yan C, Pendola FL, Jacob R, Lau AL, Eppig JJ, Matzuk MM. Oosp1 encodes a novel mouse oocyte-secreted protein. Genesis 2001; 31:105-10. [PMID: 11747200 DOI: 10.1002/gene.10010] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Oocyte-somatic cell communication is necessary for normal ovarian function. However, the identities of the majority of oocyte-secreted proteins remain unknown. A novel cDNA encoding mouse oocyte-secreted protein 1 (OOSP1) was identified using a modified subtractive hybridization screen. The Oosp1 cDNA encodes a 202-amino acid protein that contains a 21-amino acid signal peptide sequence, 5 putative N-linked glycosylation consensus sequences, and 6 cysteines that are predicted to form 3 disulfide bonds. OOSP1 shares amino acid identity with placental-specific protein 1 (PLAC1), a secreted protein expressed in the placenta and the ectoplacental cone. The Oosp1 mRNA is approximately 1.0 kb and is present at high levels in the oocytes of adult ovaries and at lower levels in the spleen. The mouse Oosp1 gene is 5 exons, spans greater than 16.4 kb, and localizes to chromosome 19 at a position that shares synteny with human chromosome 11q12-11q13. The identification of OOSP1 as a new oocyte-secreted protein permits future in vitro and in vivo functional analyses to define its role in ovarian folliculogenesis.
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202
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Takeishi Y, Huang Q, Wang T, Glassman M, Yoshizumi M, Baines CP, Lee JD, Kawakatsu H, Che W, Lerner-Marmarosh N, Zhang C, Yan C, Ohta S, Walsh RA, Berk BC, Abe J. Src family kinase and adenosine differentially regulate multiple MAP kinases in ischemic myocardium: modulation of MAP kinases activation by ischemic preconditioning. J Mol Cell Cardiol 2001; 33:1989-2005. [PMID: 11708843 DOI: 10.1006/jmcc.2001.1463] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent studies suggest that ischemia activates Src and members of the mitogen-activated protein (MAP) kinase superfamily and their downstream effectors, including big MAP kinase 1 (BMK1) and p90 ribosomal S6 kinase (p90RSK). It has also been reported that adenosine is released during ischemia and involved in triggering the protective mechanism of ischemic preconditioning. To assess the roles of Src and adenosine in ischemia-induced MAP kinases activation, we utilized the Src inhibitor PP2 (4-Amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine) and the adenosine receptor antagonist 8-(p-sulfophenyl) theophylline (SPT) in perfused guinea pig hearts. PP2 (1 microm) inhibited ischemia-induced Src, BMK1 and JNK activation but not JAK2 and p38 activation. SPT inhibited ischemia-mediated p38 and JNK activation. These results demonstrate that Src family kinase and adenosine regulate MAP kinases by parallel pathways. Preconditioning significantly improved both recovery of developed pressure and dp/dt in isolated guinea pig hearts. Since the protective effect of preconditioning was blocked by PP2 (1 microm) and SPT (50 microm), we next investigated the regulation of Src, MAP kinases and p90RSK during preconditioning. The activity and time course of ERK1/2 was not changed, but p90RSK activation by reperfusion was completely inhibited by preconditioning. In contrast, the activation by ischemia of Src, BMK1, p38 and JNK was significantly faster in preconditioned hearts. Maximal BMK1 activation by ischemia was also significantly enhanced by preconditioning. These data suggest important roles for Src family kinases and adenosine in mediating preconditioning, and suggest specific roles for individual MAP kinases in preconditioning.
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203
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Liang Y, Yan C, Schor NF. Apoptosis in the absence of caspase 3. Oncogene 2001; 20:6570-8. [PMID: 11641782 DOI: 10.1038/sj.onc.1204815] [Citation(s) in RCA: 178] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2000] [Revised: 06/14/2001] [Accepted: 07/05/2001] [Indexed: 12/17/2022]
Abstract
MCF-7 human breast cancer cells do not express caspase 3, thought by some to be a critical component of the apoptosis cascade. Nonetheless, both mock- and bcl-2-transfected MCF-7 cells undergo apoptosis after treatment with a variety of stimuli, including the DNA-cleaving antimitotic agent, neocarzinostatin (NCS). Transfection with bcl-2 shifts the concentration-response curve to NCS but does not change the phenomenology of apoptosis when it occurs. In both cases, NCS treatment results in condensation and fragmentation of MCF-7 cell nuclei and release of cytochrome c from the mitochondria to the cytosol. This apoptosis is accompanied by decreased levels of Bcl-2 and increased levels of Bax. Using a series of caspase inhibitors with overlapping specificities, enzyme-specific chromogenic substrates, and an antibody specific for activated caspase 7, we have determined that apoptosis in MCF-7 cells proceeds via sequential activation of caspases 9, 7 and 6. P21 is detected only after activation of caspase 7, and P53 is neither expressed at baseline nor up-regulated with apoptosis induction. This pathway bypasses the need for activated caspase 3 in these cells.
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204
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Che W, Abe J, Yoshizumi M, Huang Q, Glassman M, Ohta S, Melaragno MG, Poppa V, Yan C, Lerner-Marmarosh N, Zhang C, Wu Y, Arlinghaus R, Berk BC. p160 Bcr mediates platelet-derived growth factor activation of extracellular signal-regulated kinase in vascular smooth muscle cells. Circulation 2001; 104:1399-406. [PMID: 11560856 DOI: 10.1161/hc3701.095581] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The human Bcr gene was originally identified by its presence in the chimeric Bcr/Abl oncogene, which is causative for chronic myeloblastic leukemia. Because Bcr encodes a serine/threonine protein kinase, we studied its kinase activity and determined the role of Bcr in the PDGF signaling pathway to ERK1/2 activation and DNA synthesis in rat aortic smooth muscle cells (RASMCs). METHODS AND RESULTS In RASMCs, platelet-derived growth factor-BB (PDGF) stimulated Bcr kinase activity, with a maximum at 1 minute. Because phosphatidylinositol 3'-kinase (PI3-K) is essential for Bcr/Abl leukemogenesis, we evaluated the role of mouse PDGF-beta-receptor binding sites for PI3-K (Y708, Y719) and for phospholipase C-gamma (Y977, Y989) in PDGF-mediated Bcr kinase activation. The mutant PDGF receptor Y708F/Y719F but not Y977F/Y989F showed significantly reduced Bcr kinase activity. To determine the role of Bcr in PDGF-mediated signal transduction events leading to ERK1/2 and its downstream Elk1 transcription activation, wild-type (WT) and kinase-negative (KN) Bcr were transiently expressed in RASMCs. Bcr WT enhanced, whereas Bcr KN inhibited, PDGF-stimulated ERK1/2 and Elk1 transcriptional activity. Overexpression of Bcr also enhanced PDGF-induced Ras/Raf-1 activity and DNA synthesis, but this regulation is independent of the kinase activity of Bcr. Finally, we found that Bcr expression was increased in the neointimal layer after balloon injury of rat carotid artery. CONCLUSIONS These results demonstrated the importance of Bcr in PDGF-mediated events, such as activation of Ras, Raf-1, ERK1/2, and Elk1, and stimulation of DNA synthesis.
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MESH Headings
- Animals
- Aorta
- CHO Cells
- Carotid Arteries/metabolism
- Cells, Cultured
- Cricetinae
- DNA/biosynthesis
- Enzyme Activation/drug effects
- Gene Expression
- Humans
- Mitogen-Activated Protein Kinase Kinases/metabolism
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Oncogene Proteins/genetics
- Oncogene Proteins/metabolism
- Platelet-Derived Growth Factor/pharmacology
- Protein Structure, Tertiary/physiology
- Protein-Tyrosine Kinases
- Proto-Oncogene Proteins
- Proto-Oncogene Proteins c-bcr
- Proto-Oncogene Proteins c-raf/metabolism
- Rats
- Receptors, Platelet-Derived Growth Factor/genetics
- Receptors, Platelet-Derived Growth Factor/metabolism
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Transfection
- Tunica Intima/metabolism
- ras Proteins/metabolism
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205
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Zhu H, Ahmidouch A, Anklin H, Arenhövel H, Armstrong C, Bernet C, Boeglin W, Breuer H, Brindza P, Brown D, Bültmann S, Carlini R, Chant N, Cowley A, Crabb D, Danagoulian S, Day DB, Eden T, Ent R, Farah Y, Fatemi R, Garrow K, Harris C, Hauger M, Honegger A, Jourdan J, Kaufmann M, Khandaker M, Kubon G, Lichtenstadt J, Lindgren R, Lourie R, Lung A, Mack D, Malik S, Markowitz P, McFarlane K, McKee P, McNulty D, Milanovich G, Mitchell J, Mkrtchyan H, Mühlbauer M, Petitjean T, Prok Y, Rohe D, Rollinde E, Rondon OA, Roos P, Sawafta R, Sick I, Smith C, Southern T, Steinacher M, Stepanyan S, Tadevosyan V, Tieulent R, Tobias A, Vulcan W, Warren G, Wöhrle H, Wood S, Yan C, Zeier M, Zhao J, Zihlmann B. Measurement of the electric form factor of the neutron through d-->(e-->,e(')n)p at Q2 = 0.5 (GeV/c)(2). PHYSICAL REVIEW LETTERS 2001; 87:081801. [PMID: 11497934 DOI: 10.1103/physrevlett.87.081801] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2001] [Indexed: 05/23/2023]
Abstract
We report the first measurement using a solid polarized target of the neutron electric form factor G(n)(E) via d-->(e-->,e(')n)p. G(n)(E) was determined from the beam-target asymmetry in the scattering of longitudinally polarized electrons from polarized deuterated ammonia ( 15ND3). The measurement was performed in Hall C at Thomas Jefferson National Accelerator Facility in quasifree kinematics with the target polarization perpendicular to the momentum transfer. The electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle segmented detector. We find G(n)(E) = 0.04632+/-0.00616(stat)+/-0.00341(syst) at Q2 = 0.495 (GeV/c)(2).
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206
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Yan C, Wang P, DeMayo J, DeMayo FJ, Elvin JA, Carino C, Prasad SV, Skinner SS, Dunbar BS, Dube JL, Celeste AJ, Matzuk MM. Synergistic roles of bone morphogenetic protein 15 and growth differentiation factor 9 in ovarian function. Mol Endocrinol 2001; 15:854-66. [PMID: 11376106 DOI: 10.1210/mend.15.6.0662] [Citation(s) in RCA: 469] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Knockout mouse technology has been used over the last decade to define the essential roles of ovarian-expressed genes and uncover genetic interactions. In particular, we have used this technology to study the function of multiple members of the transforming growth factor-beta superfamily including inhibins, activins, and growth differentiation factor 9 (GDF-9 or Gdf9). Knockout mice lacking GDF-9 are infertile due to a block in folliculogenesis at the primary follicle stage. In addition, recombinant GDF-9 regulates multiple cumulus granulosa cell functions in the periovulatory period including hyaluronic acid synthesis and cumulus expansion. We have also cloned an oocyte-specific homolog of GDF-9 from mice and humans, which is termed bone morphogenetic protein 15 (BMP-15 or Bmp15). To define the function of BMP-15 in mice, we generated embryonic stem cells and knockout mice, which have a null mutation in this X-linked gene. Male chimeric and Bmp15 null mice are normal and fertile. In contrast to Bmp15 null males and Gdf9 knockout females, Bmp15 null females (Bmp15(-/-)) are subfertile and usually have minimal ovarian histopathological defects, but demonstrate decreased ovulation and fertilization rates. To further decipher possible direct or indirect genetic interactions between GDF-9 and BMP-15, we have generated double mutant mice lacking one or both alleles of these related homologs. Double homozygote females (Bmp15(-/-)Gdf9(-/-)) display oocyte loss and cysts and resemble Gdf9(-/-) mutants. In contrast, Bmp15(-/-)Gdf9(+/-) female mice have more severe fertility defects than Bmp15(-/-) females, which appear to be due to abnormalities in ovarian folliculogenesis, cumulus cell physiology, and fertilization. Thus, the dosage of intact Bmp15 and Gdf9 alleles directly influences the destiny of the oocyte during folliculogenesis and in the periovulatory period. These studies have important implications for human fertility control and the maintenance of fertility and normal ovarian physiology.
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207
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Burns KH, Yan C, Kumar TR, Matzuk MM. Analysis of ovarian gene expression in follicle-stimulating hormone beta knockout mice. Endocrinology 2001; 142:2742-51. [PMID: 11415992 DOI: 10.1210/endo.142.7.8279] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
FSH is a heterodimeric glycoprotein hormone that is produced in the gonadotroph cells of the anterior pituitary. It acts on Sertoli cells of the testis and granulosa cells of the ovary. We previously demonstrated that FSHbeta knockout female mice are infertile due to a block in folliculogenesis preceding antral stage development. To investigate aberrations of ovarian gene regulation in the absence of FSH, we analyzed the expression of several important marker genes using Northern blot and in situ hybridization techniques. Key findings are as follows: 1) Follicles of FSHbeta knockout mice develop a well organized thecal layer, which is positive for P450 17alpha-hydroxylase and LH receptor messenger RNAs (mRNAs). This indicates that theca recruitment is completed autonomously with respect to FSH. 2) Granulosa cells in FSH-deficient mice demonstrate an increase in FSH receptor mRNA, and decreases in P450 aromatase, serum/glucocorticoid-induced kinase, and inhibin/activin subunit mRNAs. These data support studies that implicate FSH signaling cascades in the expression of these genes. 3) In contrast to the thecal layer, granulosa cell populations in FSHbeta knockout mice do not accumulate LH receptor mRNA. This suggests that although the granulosa cells have a block in proliferation at the antral follicle stage in the absence of FSH, they do not initiate programs of terminal differentiation as seen in luteinizing cells of wild-type ovaries. 4) Ovaries of FSH-deficient mice demonstrate a modest decrease in cyclin D2 mRNA, without up-regulation of cell cycle inhibitor mRNAs associated with luteinization (i.e. p15, p27, and p21). Although components of the FSH null phenotype may be caused by partial cyclin D2 loss of function, these findings indicate that the mechanisms of granulosa cell cycle arrest in FSHbeta knockout mice are distinct from those of cycle withdrawal at luteinization. Underscoring the usefulness of the FSH-deficient mouse model, this study clarifies aspects of gonadotropin-dependent folliculogenesis, thecal layer development, cycle control in granulosa cells, and luteinization.
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208
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Scott-Lennox JA, McLaughlin-Miley C, Lennox RD, Bohlig AM, Cutler BL, Yan C, Jaffe M. Stratification of flare intensity identifies placebo responders in a treatment efficacy trial of patients with osteoarthritis. ARTHRITIS AND RHEUMATISM 2001; 44:1599-607. [PMID: 11465711 DOI: 10.1002/1529-0131(200107)44:7<1599::aid-art283>3.0.co;2-n] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Studies evaluating osteoarthritis treatment often use increased arthritis activity ("flare") as a selection criterion, although no standardized assessments are available to quantify flare intensity and little is known about how this criterion affects treatment comparisons. This study evaluated the reliability of a flare assessment and how pretreatment flare intensity impacts conclusions on treatment efficacy. METHODS Using data from a double-blind, randomized, controlled trial (n = 182), we compared 3 osteoarthritis treatments with placebo in patients who met 3 of 4 flare criteria. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was used to document levels of pain, stiffness, and physical functioning at baseline and at the final visit. Following factor analytic evaluation, the flare items were standardized and summed to create a flare intensity index, which was used to identify patient subgroups. Analysis of covariance was applied to compare change in WOMAC scale scores from baseline to final visit for assessment of treatment differences among the flare intensity subgroups. RESULTS The flare indicators appeared unidimensional. Analyses were stratified by tertiles of flare intensity. Mean WOMAC scores improved in the patients receiving active treatment who were categorized into the 2 lowest flare intensity subgroups, but mean WOMAC scores improved in patients in all 4 treatment groups (active and placebo) in the most intense flare subgroup. CONCLUSION Patients with higher intensity flares may be more likely to report substantial improvement in functional status regardless of treatment. Failure to account for flare intensity in analyses of data from pain trials with flare-based designs may inflate the risk of Type I and Type II errors in the interpretation of study results.
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209
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Yan C, Naltner A, Conkright J, Ghaffari M. Protein-protein interaction of retinoic acid receptor alpha and thyroid transcription factor-1 in respiratory epithelial cells. J Biol Chem 2001; 276:21686-91. [PMID: 11274148 DOI: 10.1074/jbc.m011378200] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Surfactant protein B (SP-B) is a 79-amino acid peptide critical to postnatal respiratory adaptation and is developmentally regulated. Previous studies demonstrated that retinoic acid receptors (RARs) and thyroid transcription factor 1 (TTF-1) stimulated SP-B gene expression in respiratory epithelial cells. Clustered retinoic acid-responsive element and TTF-1 binding sites were identified in the enhancer region of the SP-B gene and were required for retinoic acid stimulation of the human SP-B (hSP-B) promoter. In addition, RAR and TTF-1 were colocalized in mouse bronchiolar and alveolar type II epithelial cells, the cellular site of SP-B synthesis. In the present studies, RAR and TTF-1 were colocalized in the nucleus of H441 cells. RAR and TTF-1 synergistically stimulated the hSP-B promoter in H441 cells. Direct protein-protein interactions between RAR and TTF-1 were demonstrated by the glutathione S-transferase pull-down assay and the mammalian cell two hybrid assay. Truncation/deletion studies showed that the RAR-TTF-1 interaction was mediated through the RAR DNA binding domain (DBD) and the TTF-1 homeodomain. RAR DBD greatly enhanced TTF-1 homeodomain DNA binding activity to a hSP-B enhancer oligonucleotide, in which retinoic acid-responsive element and TTF-1 DNA binding sites overlap. Chromatin immunoprecipitation assay demonstrated that retinoic acid treatment of H441 cells greatly stimulated both RAR and TTF-1 DNA binding to the hSP-B enhancer region in H441 cells. These findings support a model in which RAR/retinoid X receptor, TTF-1, and coactivators (p160 members and CBP) form an enhanceosome in the enhancer region of the hSP-B gene.
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210
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Zhang M, Li J, Yan C. [Rapid synthesis and fluorescent spectra of the phosphor CaS:Eu2+ in a microwave field]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2001; 21:304-307. [PMID: 12947652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In this paper, the phosphors with CaS as the host and doped with Eu2+ ion were synthesized in a microwave field at the first time. The influence of the different concentrations of Eu2+ ion on fluorescent properties of the phosphors CaS:Eu2+ was discussed. The experimental results of SEM show that the crystallite structures of the CaS:Eu2+ with different shapes (such as cubic, spherical and rod) and different crystal sizes (100-1,500 nm), for example, nano-scale, submicron-scale or micron-scale can be obtained when doping different concentrations of Eu2+ ion. The fluorescent intensity of the sphere phosphor CaS:Eu2+ is the strongest under the excitation at 254 nm.
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211
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Yan C, Zhao AZ, Sonnenburg WK, Beavo JA. Stage and cell-specific expression of calmodulin-dependent phosphodiesterases in mouse testis. Biol Reprod 2001; 64:1746-54. [PMID: 11369604 DOI: 10.1095/biolreprod64.6.1746] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Calcium and cyclic nucleotides are second messengers that regulate the development and functional activity of spermatozoa. Calcium/calmodulin-dependent phosphodiesterases (CaM-PDEs) are abundant in testicular cells and in mature spermatozoa and provide one means by which calcium regulates cellular cyclic nucleotide content. We examined the spatial and temporal expression profiles of three knownCaM-PDE genes, PDE1A, PDE1B, and PDE1C, in the testis. In situ hybridization and immunofluorescent staining showed that both PDE1A and PDE1C are highly expressed but at different stages in developing germ cells. However, a very low hybridization signal of PDE1B exists uniformly throughout the seminiferous epithelium and the interstitium. More specifically, PDE1A mRNA is found in round to elongated spermatids, with protein expression in the tails of elongated and maturing spermatids. In contrast, PDE1C mRNA accumulates during early meiotic prophase and throughout meiotic and postmeiotic stages. Immunocytochemistry showed a diffuse, presumably cytosolic distribution of the expressed protein. The distinct spatial and temporal expression patterns of CaM-PDEs suggest important but different physiological roles for these CaM-PDEs in developing and mature spermatozoa.
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212
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Surapisitchat J, Hoefen RJ, Pi X, Yoshizumi M, Yan C, Berk BC. Fluid shear stress inhibits TNF-alpha activation of JNK but not ERK1/2 or p38 in human umbilical vein endothelial cells: Inhibitory crosstalk among MAPK family members. Proc Natl Acad Sci U S A 2001; 98:6476-81. [PMID: 11353829 PMCID: PMC33493 DOI: 10.1073/pnas.101134098] [Citation(s) in RCA: 190] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Atherosclerosis preferentially occurs in areas of turbulent flow and low fluid shear stress, whereas laminar flow and high shear stress are atheroprotective. Inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and IL-1 stimulate expression of endothelial cell (EC) genes that may promote atherosclerosis. TNF-alpha and IL-1 regulate gene expression in ECs, in part, by stimulating mitogen-activated protein kinases (MAPK), which phosphorylate transcription factors. We hypothesized that steady laminar flow inhibits cytokine-mediated activation of MAPK in EC. To test this hypothesis, we determined the effects of flow (shear stress = 12 dynes/cm(2)) on TNF-alpha and IL-1-stimulated activity of three MAPK in human umbilical vein ECs (HUVEC): extracellular signal-regulated kinase (ERK1/2), p38, and c-Jun N-terminal kinase (JNK). Flow alone stimulated ERK1/2 and p38 activity but decreased JNK activity compared with static controls. TNF-alpha or IL-1 alone activated ERK1/2, p38, and JNK maximally at 15 min in HUVEC. Preexposing HUVEC for 10 min to flow inhibited TNF-alpha and IL-1 activation of JNK by 46% and 49%, respectively, but had no significant effect on ERK1/2 or p38 activation. Incubation of HUVEC with PD98059, which inhibits flow-mediated ERK1/2 activation, prevented flow from inhibiting cytokine activation of JNK. Phorbol 12-myristate 13-acetate, which strongly activates ERK1/2, also inhibited TNF-alpha activation of JNK. These findings indicate that fluid shear stress inhibits TNF-alpha-mediated signaling events in HUVEC via the activation of the ERK1/2 signaling pathway. Inhibition of TNF-alpha signal transduction represents a mechanism by which steady laminar flow may exert atheroprotective effects on the endothelium.
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213
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Jiang T, Yu C, Guo E, Guan S, Yan C. [Anatomicopathological relation between facial nerve and large vestibular Schwannoma]. ZHONGHUA YI XUE ZA ZHI 2001; 81:536-7. [PMID: 11809117] [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 anatomicopathological relation between facial nerve and large vestibular schwannoma. METHODS Operation by suboccipital retrosigmoid sinus approach was performed on 40 cases with large vestibular schwannoma, During the operation, the anatomicopathological relation between the facial nerve and the vestibular schwannoma was observed directly. RESULTS The facial nerve was found to be located ventrally (deep under the tumor), dorsally (over the tumor), at the upper pole of the tumor (near the tentorium cerebelli), at the lower pole of the tumor (near the rear group cranial nerves), or aberrant (unable to be identified because of infiltration of tumor). In 31 cases, mainly with parenchymatous tumor, the facial nerve was flat in shape. In 9 cases, mainly with cystic tumor, the facial nerve was bandlike. CONCLUSION The facial nerve varies greatly in neuroanatomy among patients with large vestibular schwannoma. Strengthening of operative monitoring can increase the safety of operation.
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214
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Jiang ZJ, Gao RY, Zhang K, Zhang ZC, Wang QS, Yan C. [Enantiomeric separations of 1-1,2,4-triazole compounds by micro-high performance liquid chromatography]. Se Pu 2001; 19:253-5. [PMID: 12541811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
The enantiomeric separations of sixteen novel 1-1,2,4-triazole chiral compounds were investigated by micro-HPLC with a 200 mm x 100 microns i.d. capillary chiral OD column. The detection was performed at 223 nm. The mobile phase was a mixture of iso-propyl alcohol and n-hexane(20:80, V/V) at a flow rate of 30 microL/min and column head pressure of 6.9 MPa. Some of the enantiomers could be separated on baseline. In comparing with the separation results by the conventional HPLC method, the micro-HPLC method had the advantages of high-speed, economy, environmental friendliness etc. The effect of solute structure on enantio-selectivity was investigated and the chiral recognition mechanism was also discussed. It was found that the main separation mechanisms involve the pi-pi association and inclusion between the substituent R and the spiral pocket of OD-CSP.
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215
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Yan C, Luo H, Lee JD, Abe J, Berk BC. Molecular cloning of mouse ERK5/BMK1 splice variants and characterization of ERK5 functional domains. J Biol Chem 2001; 276:10870-8. [PMID: 11139578 DOI: 10.1074/jbc.m009286200] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mitogen-activated protein kinases (MAPKs) play important roles in regulation of cell growth and survival. Human MAPK 5 (ERK5) or Big MAP kinase 1 (BMK1) is a recently cloned member of the MAPK family. To identify ERK5-related kinases, we searched the GenBanktrade mark expressed sequence tag (EST) data base for mouse cDNAs with homology to human ERK5. A full-length mouse cDNA that was highly homologous to the human ERK5 was identified. Further analysis of ERK5 polymerase chain reaction products generated from mouse embryo cDNA yielded three mouse ERK5 cDNAs (mERK5a, mERK5b, and mERK5c). Sequence analysis showed that these cDNAs are alternative splice products of the mouse ERK5 gene. Interestingly, expressed mERK5b and mERK5c act as dominant negative inhibitors based on inhibition of mERK5a kinase activity and mERK5a-mediated MEF2C transactivation. However, the physiological significance of mERK5b and mERK5c is not fully understood. Further investigation using these mouse ERK5 splice variants and other constructed mutants identified functional roles of several regions of mERK5, which appear to be important for protein-protein interaction and intracellular localization. Specifically, we found that the long C-terminal tail, which contains a putative nuclear localization signal, is not required for activation and kinase activity but is responsible for the activation of nuclear transcription factor MEF2C due to nuclear targeting. In addition, the N-terminal domain spanning amino acids (aa) 1-77 is important for cytoplasmic targeting; the domain from aa 78 to 139 is required for association with the upstream kinase MEK5; and the domain from aa 140-406 is necessary for oligomerization. Taken together, these observations indicate that ERK5 is regulated by distinct mechanisms determined by its unique structure and presumably the presence of multiple splice variants.
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216
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Wang B, Yan C, Wu Y, Gao H, Wang Q, Jin Y, Huang C, Zhang G, Fu S, Li P. [Expression of tumor suppressor genes p16, p21 and p53 in a pair of lung adenocarcinoma cell lines with different metastasis potentials: Anip973 and AGZY83-a]. ZHONGHUA YI XUE YI CHUAN XUE ZA ZHI = ZHONGHUA YIXUE YICHUANXUE ZAZHI = CHINESE JOURNAL OF MEDICAL GENETICS 2001; 18:128-31. [PMID: 11295133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE In order to investigate the suppression effect of tumor suppressor genes in lung adenocarcinoma. METHODS p16 and p21 expression vectors were transfected into a pair of lung adenocarcinoma cell lines with different metastasis potentials: Anip973(high metastasis potential)and AGZY83-a (low metastasis potential). In the mean time, AGZY83-a, Anip973, AGZY83-ap16 and Anip973p16 were infected with recombinant adenovirus encoding wild- type p53 gene. The suppression effects of these genes were evaluated by cell growth curve, MTT, cloning efficiency assay, flow cytometric analysis and TUNEL technique. RESULTS Overexpression of p16 gene in Anip973 and AGZY83-a could only lengthen the G(1) phase while increased expression of p21 in both of the cell lines was associated with significant lengthening of G(1) phase, decreased proliferation potential and decreased cloning efficiency. High efficient expression of wild-type p53 gene in AGZY83-a, Anip973, Anip973p16 and AGZY83-ap16 inhibited the growth of these four kinds of lung cancer cells and killed the cells in the end. Apoptosis was detected in all the four kinds of cells. The suppression effect of p53 gene was higher in Anip973 and Anip973p16 than in AGZY83-a and AGZY83-ap16 while co-expression of p53 and p16 in this pair of cell lines inhibited the cells more efficiently as compared with the expression of p53 gene. CONCLUSION Increased expression of p21 gene suppressed the lung adenocarcinoma cells by G(1) arrest and the co-transfection of tumor suppressor genes p16 and p53 into the lung adenocarcinoma cell line proved more effective in lung cancer gene therapy.
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Sang Y, Yan C, Zhu C, Ni G. Relationship between HLA-DRB1 and DQ alleles and the genetic susceptibility to type 1 diabetes. Chin Med J (Engl) 2001; 114:407-9. [PMID: 11780465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To study the relationship between human leukocyte antigen (HLA)-DRB1 and DQ alleles and the genetic susceptibility of type 1 diabetes in North Chinese children. METHODS Polymerase chain reaction (PCR) techniques were used to amplify the second exon of DRB1 and DQ alleles, after which sequence specific olignucleotide probe (SSOP) dot blot hybridization techniques were used to analyze the amplified products. RESULTS DRB1 * 0301, DQA1 * 0301, DQB1 * 0201 alleles and DRB1 * 0301-DQA1 * 0501-DQB1 * 0201 haplotype were significantly increased in patients, while DQA1 * 0103 and DQB1 * 0601 alleles were significantly increased in controls. The distribution of DR4 and DR9 haplotypes in patients and controls were not significantly different, but DR3/DR4 and DR4/DR9 heterozygotes were significantly increased in patients. CONCLUSIONS DRB1 * 0301, DQA1 * 0301 and DQB1 * 0201 confer susceptibility while DQA1 * 0103 and DQB1 * 0601 confer protection to type 1 diabetes. DRB1 * 0301-DQA1 * 0501-DQB1 * 0201 haplotype offers a predisposition to type 1 diabetes in North Chinese. Although the distribution of DR4 and DR9 in patients and controls had no significant difference, DR3/DR4 and DR3/DR9 heterozygotes were significantly increased in patients, showing that the susceptive effects of DR3 and DR4 or DR4 and DR9 haplotypes could be added up.
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Cao G, Minami M, Pei W, Yan C, Chen D, O'Horo C, Graham SH, Chen J. Intracellular Bax translocation after transient cerebral ischemia: implications for a role of the mitochondrial apoptotic signaling pathway in ischemic neuronal death. J Cereb Blood Flow Metab 2001; 21:321-33. [PMID: 11323518 DOI: 10.1097/00004647-200104000-00001] [Citation(s) in RCA: 169] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Activation of terminal caspases such as caspase-3 plays an important role in the execution of neuronal cell death after transient cerebral ischemia. Although the precise mechanism by which terminal caspases are activated in ischemic neurons remains elusive, recent studies have postulated that the mitochondrial cell death-signaling pathway may participate in this process. The bcl-2 family member protein Bax is a potent proapoptotic molecule that, on translocation from cytosol to mitochondria, triggers the activation of terminal caspases by increasing mitochondrial membrane permeability and resulting in the release of apoptosis-promoting factors, including cytochrome c. In the present study, the role of intracellular Bax translocation in ischemic brain injury was investigated in a rat model of transient focal ischemia (30 minutes) and reperfusion (1 to 72 hours). Immunochemical studies revealed that transient ischemia induced a rapid translocation of Bax from cytosol to mitochondria in caudate neurons, with a temporal profile and regional distribution coinciding with the mitochondrial release of cytochrome c and caspase-9. Further, in postischemic caudate putamen in vivo and in isolated brain mitochondria in vitro, the authors found enhanced heterodimerization between Bax and the mitochondrial membrane permeabilization-related proteins adenine nucleotide translocator (ANT) and voltage-dependent anion channel. The ANT inhibitor bongkrekic acid prevented Bax and ANT interactions and inhibited Bax-triggered caspase-9 release from isolated brain mitochondria in vitro. Bongkrekic acid also offered significant neuroprotection against ischemia-induced caspase-3 and caspase-9 activation and cell death in the brain. These results strongly suggest that the Bax-mediated mitochondrial apoptotic signaling pathway may play an important role in ischemic neuronal injury.
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Volmer J, Abbott D, Anklin H, Armstrong C, Arrington J, Assamagan K, Avery S, Baker OK, Blok HP, Bochna C, Brash EJ, Breuer H, Chant N, Dunne J, Eden T, Ent R, Gaskell D, Gilman R, Gustafsson K, Hinton W, Huber GM, Jackson H, Jones MK, Keppel C, Kim PH, Kim W, Klein A, Koltenuk D, Liang M, Lolos GJ, Lung A, Mack DJ, McKee D, Meekins D, Mitchell J, Mkrtchyan H, Mueller B, Niculescu G, Niculescu I, Pitz D, Potterveld D, Qin LM, Reinhold J, Shin IK, Stepanyan S, Tadevosyan V, Tang LG, van der Meer RL, Vansyoc K, Van Westrum D, Vulcan W, Wood S, Yan C, Zhao WX, Zihlmann B. Measurement of the charged pion electromagnetic form factor. PHYSICAL REVIEW LETTERS 2001; 86:1713-1716. [PMID: 11290230 DOI: 10.1103/physrevlett.86.1713] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2000] [Indexed: 05/23/2023]
Abstract
Separated longitudinal and transverse structure functions for the reaction 1H(e,e(')pi(+))n were measured in the momentum transfer region Q2 = 0.6--1.6 (GeV/c)(2) at a value of the invariant mass W = 1.95 GeV. New values for the pion charge form factor were extracted from the longitudinal cross section by using a recently developed Regge model. The results indicate that the pion form factor in this region is larger than previously assumed and is consistent with a monopole parametrization fitted to very low Q2 elastic data.
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Venter JC, Adams MD, Myers EW, Li PW, Mural RJ, Sutton GG, Smith HO, Yandell M, Evans CA, Holt RA, Gocayne JD, Amanatides P, Ballew RM, Huson DH, Wortman JR, Zhang Q, Kodira CD, Zheng XH, Chen L, Skupski M, Subramanian G, Thomas PD, Zhang J, Gabor Miklos GL, Nelson C, Broder S, Clark AG, Nadeau J, McKusick VA, Zinder N, Levine AJ, Roberts RJ, Simon M, Slayman C, Hunkapiller M, Bolanos R, Delcher A, Dew I, Fasulo D, Flanigan M, Florea L, Halpern A, Hannenhalli S, Kravitz S, Levy S, Mobarry C, Reinert K, Remington K, Abu-Threideh J, Beasley E, Biddick K, Bonazzi V, Brandon R, Cargill M, Chandramouliswaran I, Charlab R, Chaturvedi K, Deng Z, Di Francesco V, Dunn P, Eilbeck K, Evangelista C, Gabrielian AE, Gan W, Ge W, Gong F, Gu Z, Guan P, Heiman TJ, Higgins ME, Ji RR, Ke Z, Ketchum KA, Lai Z, Lei Y, Li Z, Li J, Liang Y, Lin X, Lu F, Merkulov GV, Milshina N, Moore HM, Naik AK, Narayan VA, Neelam B, Nusskern D, Rusch DB, Salzberg S, Shao W, Shue B, Sun J, Wang Z, Wang A, Wang X, Wang J, Wei M, Wides R, Xiao C, Yan C, Yao A, Ye J, Zhan M, Zhang W, Zhang H, Zhao Q, Zheng L, Zhong F, Zhong W, Zhu S, Zhao S, Gilbert D, Baumhueter S, Spier G, Carter C, Cravchik A, Woodage T, Ali F, An H, Awe A, Baldwin D, Baden H, Barnstead M, Barrow I, Beeson K, Busam D, Carver A, Center A, Cheng ML, Curry L, Danaher S, Davenport L, Desilets R, Dietz S, Dodson K, Doup L, Ferriera S, Garg N, Gluecksmann A, Hart B, Haynes J, Haynes C, Heiner C, Hladun S, Hostin D, Houck J, Howland T, Ibegwam C, Johnson J, Kalush F, Kline L, Koduru S, Love A, Mann F, May D, McCawley S, McIntosh T, McMullen I, Moy M, Moy L, Murphy B, Nelson K, Pfannkoch C, Pratts E, Puri V, Qureshi H, Reardon M, Rodriguez R, Rogers YH, Romblad D, Ruhfel B, Scott R, Sitter C, Smallwood M, Stewart E, Strong R, Suh E, Thomas R, Tint NN, Tse S, Vech C, Wang G, Wetter J, Williams S, Williams M, Windsor S, Winn-Deen E, Wolfe K, Zaveri J, Zaveri K, Abril JF, Guigó R, Campbell MJ, Sjolander KV, Karlak B, Kejariwal A, Mi H, Lazareva B, Hatton T, Narechania A, Diemer K, Muruganujan A, Guo N, Sato S, Bafna V, Istrail S, Lippert R, Schwartz R, Walenz B, Yooseph S, Allen D, Basu A, Baxendale J, Blick L, Caminha M, Carnes-Stine J, Caulk P, Chiang YH, Coyne M, Dahlke C, Deslattes Mays A, Dombroski M, Donnelly M, Ely D, Esparham S, Fosler C, Gire H, Glanowski S, Glasser K, Glodek A, Gorokhov M, Graham K, Gropman B, Harris M, Heil J, Henderson S, Hoover J, Jennings D, Jordan C, Jordan J, Kasha J, Kagan L, Kraft C, Levitsky A, Lewis M, Liu X, Lopez J, Ma D, Majoros W, McDaniel J, Murphy S, Newman M, Nguyen T, Nguyen N, Nodell M, Pan S, Peck J, Peterson M, Rowe W, Sanders R, Scott J, Simpson M, Smith T, Sprague A, Stockwell T, Turner R, Venter E, Wang M, Wen M, Wu D, Wu M, Xia A, Zandieh A, Zhu X. The sequence of the human genome. Science 2001; 291:1304-51. [PMID: 11181995 DOI: 10.1126/science.1058040] [Citation(s) in RCA: 7683] [Impact Index Per Article: 334.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A 2.91-billion base pair (bp) consensus sequence of the euchromatic portion of the human genome was generated by the whole-genome shotgun sequencing method. The 14.8-billion bp DNA sequence was generated over 9 months from 27,271,853 high-quality sequence reads (5.11-fold coverage of the genome) from both ends of plasmid clones made from the DNA of five individuals. Two assembly strategies-a whole-genome assembly and a regional chromosome assembly-were used, each combining sequence data from Celera and the publicly funded genome effort. The public data were shredded into 550-bp segments to create a 2.9-fold coverage of those genome regions that had been sequenced, without including biases inherent in the cloning and assembly procedure used by the publicly funded group. This brought the effective coverage in the assemblies to eightfold, reducing the number and size of gaps in the final assembly over what would be obtained with 5.11-fold coverage. The two assembly strategies yielded very similar results that largely agree with independent mapping data. The assemblies effectively cover the euchromatic regions of the human chromosomes. More than 90% of the genome is in scaffold assemblies of 100,000 bp or more, and 25% of the genome is in scaffolds of 10 million bp or larger. Analysis of the genome sequence revealed 26,588 protein-encoding transcripts for which there was strong corroborating evidence and an additional approximately 12,000 computationally derived genes with mouse matches or other weak supporting evidence. Although gene-dense clusters are obvious, almost half the genes are dispersed in low G+C sequence separated by large tracts of apparently noncoding sequence. Only 1.1% of the genome is spanned by exons, whereas 24% is in introns, with 75% of the genome being intergenic DNA. Duplications of segmental blocks, ranging in size up to chromosomal lengths, are abundant throughout the genome and reveal a complex evolutionary history. Comparative genomic analysis indicates vertebrate expansions of genes associated with neuronal function, with tissue-specific developmental regulation, and with the hemostasis and immune systems. DNA sequence comparisons between the consensus sequence and publicly funded genome data provided locations of 2.1 million single-nucleotide polymorphisms (SNPs). A random pair of human haploid genomes differed at a rate of 1 bp per 1250 on average, but there was marked heterogeneity in the level of polymorphism across the genome. Less than 1% of all SNPs resulted in variation in proteins, but the task of determining which SNPs have functional consequences remains an open challenge.
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Wei F, Jiang Z, Yan C. Analysis of 20 mature ovarian cystic teratoma cases in postmenopausal women. Chin Med J (Engl) 2001; 114:137-8. [PMID: 11780192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To study the incidence of malignant change, diagnosis and management of mature cystic teratomas in postmenopausal women. METHODS Twenty cases of mature cystic teratoma in postmenopausal women admitted to our hospital between January 1977 and January 1997 was retrospectively reviewed and evaluated. RESULTS The number of postmenopausal patients with mature cystic teratoma (20) accounted for 7.6% of the total number of patients with benign ovarian teratomas (263). There were 3 cases of malignant change, which were squamous carcinoma, carcinosarcoma, and digestive gland epithelial carcinoma. The incidence of malignant change was 15%. CONCLUSION In postmenopausal women, mature ovarian cystic teratoma should be treated as lowly malignant and should be paid much attention.
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Cavanaugh JE, Ham J, Hetman M, Poser S, Yan C, Xia Z. Differential regulation of mitogen-activated protein kinases ERK1/2 and ERK5 by neurotrophins, neuronal activity, and cAMP in neurons. J Neurosci 2001; 21:434-43. [PMID: 11160424 PMCID: PMC6763829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Activation of the extracellular signal-regulated kinase 1 (ERK1) and ERK2 by neurotrophins, neuronal activity, or cAMP has been strongly implicated in differentiation, survival, and adaptive responses of neurons during development and in the adult brain. Recently, a new member of the mitogen-activated protein (MAP) kinase family, ERK5, was discovered. Like ERK1 and ERK2, ERK5 is expressed in neurons, and ERK5 stimulation by epidermal growth factor is blocked by the MAP kinase/ERK kinase 1 (MEK1) inhibitors PD98059 and U0126. This suggests the interesting possibility that some of the functions attributed to ERK1/2 may be mediated by ERK5. However, the regulatory properties of ERK5 in primary cultured neurons have not been reported. Here we examined the regulation of ERK5 signaling in primary cultured cortical neurons. Our data demonstrate that, similar to ERK1/2, ERK5 is activated by neurotrophins including brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and NT-4. BDNF stimulation of ERK5 required the activity of MEK5. Surprisingly, ERK5 was not stimulated by cAMP or neuronal activity induced by glutamate or membrane depolarization. In contrast to ERK1/2, ERK5 strongly activated the transcriptional activity of myocyte enhancer factor 2C (MEF2C) in pheochromocytoma 12 (PC12) cells and was required for neurotrophin stimulation of MEF2C transcription in both PC12 cells and cortical neurons. Furthermore, ERK1/2, but not ERK5, induced transcription from Elk1 and the cAMP/ Ca(2+) response element in PC12 cells. Our data suggest that mechanisms for regulation of ERK5 and downstream transcriptional pathways regulated by ERK5 are distinct from those of ERK1/2 in neurons. Furthermore, ERK5 is the first MAP kinase identified whose activity is stimulated by neurotrophins but not by neuronal activity.
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Yan C, Wang H, Boyd DD. KiSS-1 represses 92-kDa type IV collagenase expression by down-regulating NF-kappa B binding to the promoter as a consequence of Ikappa Balpha -induced block of p65/p50 nuclear translocation. J Biol Chem 2001; 276:1164-72. [PMID: 11060311 DOI: 10.1074/jbc.m008681200] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The 92-kDa type IV collagenase (MMP-9) plays a critical role in tissue remodeling. We undertook a study to determine whether the KiSS-1 gene, previously shown to suppress cancer spread (metastases), negatively regulates MMP-9 expression. Six cell lines positive for MMP-9 mRNA were deficient in KiSS-1 mRNA. One of these cell lines, HT-1080, stably transfected with a KiSS-1 expression construct, demonstrated substantially lower MMP-9 enzyme activity/protein and in vitro invasiveness. The lower MMP-9 enzyme activity reflected reduced steady-state mRNA levels which, in turn, was due to attenuated transcription. Activation of ERKs and JNKs by phorbol 12-myristate 13-acetate and tumor necrosis factor alpha, respectively, leading to increased MMP-9 amounts was not antagonized by KiSS-1 expression, suggesting that MAPK pathways modulating MMP-9 synthesis are not the target of KiSS-1. Although MMP-9 expression is regulated by AP-1, Sp1, and Ets transcription factors, KiSS-1 did not alter the binding of these factors to the MMP-9 promoter. However, NF-kappaB binding to the MMP-9 promoter required for expression of this collagenase was reduced by KiSS-1 expression. Diminished NF-kappaB binding reflected less p50/p65 in the nucleus secondary to increased IkappaBalpha levels in the cytosols of the KiSS-1 transfectants. Thus, KiSS-1 diminishes MMP-9 expression by effecting reduced NF-kappaB binding to the promoter.
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Yan C, Matzuk MM. Transgenic models of ovarian failure. JOURNAL OF THE SOCIETY FOR GYNECOLOGIC INVESTIGATION 2001; 8:S30-3. [PMID: 11223368 DOI: 10.1016/s1071-5576(00)00103-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Reproductive development and function are a complex process requiring the coordinate interactions of multiple extragonadal and intragonadal factors. Peptide hormones from the hypothalamus (eg, gonadotropin releasing hormone) and the pituitary (eg, follicle stimulating hormone, luteinizing hormone, oxytocin) as well as growth factors and steroids from the gonads (eg, inhibins, growth differentiation factor-9, progesterone, estradiol, testosterone) play key functions in regulating specific aspects of reproduction. Our laboratory used spontaneous mutant mice and transgenic mouse models to address the essential roles of some of these factors in the propagation of the mammalian species. This review summarizes some of our initial studies to understand this process.
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Wei Z, Yin M, Zhang X, Hong F, Li B, Tao Y, Zhao G, Yan C. Rare earth elements in naturally grown fern Dicranopteris linearis in relation to their variation in soils in south-Jiangxi region (southern China). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2001; 114:345-355. [PMID: 11584633 DOI: 10.1016/s0269-7491(00)00240-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Ferns (Dicranopteris linearis) and soils, sampled from four rare earth mining areas and one non-mining area locating in South-Jiangxi region, were chosen for analysis of 15 rare earth elements (REEs) by inductively coupled plasma-mass spectrometry (ICP-MS). The fern samples were divided into 4 parts: root, stem, petiole, and lamina. The soils of the same sites were also sampled, and 4 soil layers were observed at the profile: A (0-20 cm depth), B (20-150 cm depth), C (150-400 cm depth), and D (rock). The distribution patterns and transportation characteristics of REEs of different soil layers and of different parts of D. linearis were studied. The results showed that in the soil layers, the sigma REE (the sum of the concentrations of 15 REEs) of A layer, as well as B layer were lower than that of C layer, but Ce was relatively concentrated in A layer. The sigma REE of different parts of D. linearis were lamina, root > stem > petiole. The REE distribution patterns of D. linearis root were similar to the total REE distribution patterns of the A layer of their host soils, especially to the soluble REE distribution patterns of the A layer of their host soils. The REEs were fractionated in their transportation in D. linearis. The abundances of heavy rare earth elements (HREEs, Gd to Lu and Y) in the stem, petiole, lamina are lower than those in the root.
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Yan C, Ikezoe K, Nonaka I. Apoptotic muscle fiber degeneration in distal myopathy with rimmed vacuoles. Acta Neuropathol 2001; 101:9-16. [PMID: 11194945 DOI: 10.1007/s004010000249] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Rimmed vacuole formation, tubulofilamentous nuclear inclusions and muscle fiber atrophy are the characteristic pathological findings in distal myopathy with rimmed vacuoles (DMRV). Necrotic muscle fibers were few in number and did not appear to account for the muscle weakness, but the nuclear changes with myofibrillar degeneration followed by rimmed vacuole formation appeared to be the major reason for the muscle fiber atrophy in DMRV. To determine whether the nuclear change in DMRV was related to apoptosis, we examined 15 muscle biopsy specimens immunohistochemically, and 7 of them ultrastructurally. The characteristic tubulofilamentous nuclear inclusions were found in 4 and the typical fragmented apoptotic nuclei in 3 of the 7 muscle biopsy samples examined by electron microscopy. TUNEL-positive nuclei reflecting apoptotic DNA fragmentation were found in 13 of 15 biopsies ranging from a few to approximately 1.5% of myonuclei. Apoptosis-specific protein was expressed in the sarcoplasm of atrophic fibers in 13 biopsies both with or without rimmed vacuoles. These findings suggest that the apoptotic process plays a crucial role in myofibrillar degeneration followed by autophagocytosis, i.e., rimmed vacuole formation, in DMRV.
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Yan C, Peng N. [A survey of the International Symposium on Economic Development and Social Change]. LISHI YANJIU 2001:178-83. [PMID: 17910133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
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Naltner A, Wert S, Whitsett JA, Yan C. Temporal/spatial expression of nuclear receptor coactivators in the mouse lung. Am J Physiol Lung Cell Mol Physiol 2000; 279:L1066-74. [PMID: 11076796 DOI: 10.1152/ajplung.2000.279.6.l1066] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Our laboratory has previously demonstrated that retinoic acid nuclear receptor, thyroid transcription factor-1 (TTF-1), and nuclear receptor coactivators such as cAMP response element binding protein (CREB) binding protein (CBP)/p300 and steroid receptor coactivator-1 (SRC-1) form an enhanceosome on the 5'-enhancer region of the human surfactant protein B gene. Immunohistochemistry was used to identify cells that coexpressed CBP/p300, SRC-1, retinoid X receptor, and TTF-1 in the developing and mature lung. CBP/p300 and SRC-1 were expressed in the adult mouse lung, CBP and p300 being present in both alveolar type I and type II epithelial cells and SRC-1 and TTF-1 being restricted to type II epithelial cells. CBP/p300, SRC-1, and TTF-1 were readily detected in the nuclei of developing respiratory epithelial tubules in fetal mice from embryonic days 10 to 18. CBP/p300 and SRC-1 were also detected in developing mesenchymal cells. These coactivators were coexpressed with TTF-1 and SP-B in human pulmonary adenocarcinoma cells (H441 cells) in vitro. Interaction assays with a two-hybrid reporter analysis demonstrated direct interactions among TTF-1, SRC-1, and CBP/p300 in H441 cells. These findings support a role for retinoic acid receptor and nuclear receptor coactivators in the regulation of SP-B gene expression in the respiratory epithelium.
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Jin ZG, Melaragno MG, Liao DF, Yan C, Haendeler J, Suh YA, Lambeth JD, Berk BC. Cyclophilin A is a secreted growth factor induced by oxidative stress. Circ Res 2000; 87:789-96. [PMID: 11055983 DOI: 10.1161/01.res.87.9.789] [Citation(s) in RCA: 286] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Reactive oxygen species have been implicated in the pathogenesis of atherosclerosis, hypertension, and restenosis, in part by promoting vascular smooth muscle cell (VSMC) growth. Many VSMC growth factors are secreted by VSMC and act in an autocrine manner. Here we demonstrate that cyclophilin A (CyPA), a member of the immunophilin family, is secreted by VSMCs in response to oxidative stress and mediates extracellular signal-regulated kinase (ERK1/2) activation and VSMC growth by reactive oxygen species. Human recombinant CyPA can mimic the effects of secreted CyPA to stimulate ERK1/2 and cell growth. The peptidyl-prolyl isomerase activity is required for ERK1/2 activation by CyPA. In vivo, CyPA expression and secretion are increased by oxidative stress and vascular injury. These findings are the first to identify CyPA as a secreted redox-sensitive mediator, establish CyPA as a VSMC growth factor, and suggest an important role for CyPA and enzymes with peptidyl-prolyl isomerase activity in the pathogenesis of vascular diseases.
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Ru QH, Yao J, Luo GA, Zhang YX, Yan C. Pressurized gradient capillary electrochromatographic separation of eighteen amino acid derivatives. J Chromatogr A 2000; 894:337-43. [PMID: 11100877 DOI: 10.1016/s0021-9673(00)00712-3] [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: 11/26/2022]
Abstract
A pressurized gradient capillary electrochromatography (pCEC) instrument was developed to separate 18 amino acid derivatives. A reversed-phase C18 column (3 microm, 130 mm x 75 microm I.D.) and an acetate buffer (50 mmol/l NaAc, pH 6.4) with an ion-pair reagent (1% N,N-dimethylformamide) were used to separate derivatized amino acids from a standard solution (2 microg/ml), and the wavelength of the UV-Vis detector was 360 nm. The pressure on the capillary column was kept at approx. 70 Pa and 3 kV positive voltage was added on the outlet end of column. The effect of voltage on the eluting order of amino acids and the resolution of separation were studied, and it was found that when the voltage was higher than 3 kV, the adsorption of amino acids in the porous C18 column occurred. The effect of salt concentration, injection volume, and column length on the separation of amino acids was determined. The amino acid sample was separated by pCEC, and RSDs of the migration times of each amino acid were all less than 2.5%.
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Ochiai Y, Fukushi H, Yan C, Yamaguchi T, Hirai K. Comparative analysis of the putative amino acid sequences of chlamydial heat shock protein 60 and Escherichia coli GroEL. J Vet Med Sci 2000; 62:941-5. [PMID: 11039588 DOI: 10.1292/jvms.62.941] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The nucleotide sequences of the gene encoding chlamydial heat shock protein 60 (cHSP60) of 7 Chlamydia psittaci strains were determined. Comparison of sequences of the cHSP60 gene among chlamydiae showed high identities of the nucleotide sequences by 81.0% or greater and of the deduced amino acid sequences by 92.2% or greater. Comparison of the amino acid sequences between chlamydia and the other bacterial HSP60s resulted in the finding of three highly conserved regions, suggesting that these regions play a role in some function. In addition, 26- or 27-functional residues in the Escherichia coli GroEL out of the 28-residues are conserved in the amino acid sequences of the cHSP60. The data suggest that the function of the cHSP60 may be the same as that of the E. coli GroEL.
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Elvin JA, Yan C, Matzuk MM. Growth differentiation factor-9 stimulates progesterone synthesis in granulosa cells via a prostaglandin E2/EP2 receptor pathway. Proc Natl Acad Sci U S A 2000; 97:10288-93. [PMID: 10944203 PMCID: PMC27877 DOI: 10.1073/pnas.180295197] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2000] [Accepted: 06/27/2000] [Indexed: 11/18/2022] Open
Abstract
Growth differentiation factor-9 (GDF-9), an oocyte-secreted member of the transforming growth factor beta superfamily, progesterone receptor, cyclooxygenase 2 (Cox2; Ptgs2), and the EP2 prostaglandin E(2) (PGE(2)) receptor (EP2; Ptgerep2) are required for fertility in female but not male mice. To define the interrelationship of these factors, we used a preovulatory granulosa cell culture system in which we added recombinant GDF-9, prostaglandins, prostaglandin receptor agonists, or cyclooxygenase inhibitors. GDF-9 stimulated Cox2 mRNA within 2 h, and PGE(2) within 6 h; however, progesterone was not increased until 12 h after addition of GDF-9. This suggested that Cox2 is a direct downstream target of GDF-9 but that progesterone synthesis required an intermediate. To determine whether prostaglandin synthesis was required for progesterone production, we analyzed the effects of PGE(2) and cyclooxygenase inhibitors on this process. PGE(2) can stimulate progesterone synthesis by itself, although less effectively than GDF-9 (3-fold vs. 6-fold increase over 24 h, respectively). Furthermore, indomethacin or NS-398, inhibitors of Cox2, block basal and GDF-9-stimulated progesterone synthesis. However, addition of PGE(2) to cultures containing both GDF-9 and NS-398 overrides the NS-398 block in progesterone synthesis. To further define the PGE(2)-dependent pathway, we show that butaprost, a specific EP2 agonist, stimulates progesterone synthesis and overrides the NS-398 block. In addition, GDF-9 stimulates EP2 mRNA synthesis by a prostaglandin- and progesterone-independent pathway. Thus, GDF-9 induces an EP2 signal transduction pathway which appears to be required for progesterone synthesis in cumulus granulosa cells. These studies further demonstrate the importance of oocyte-somatic cell interactions in female reproduction.
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Han X, Yan C, Chen L, Mei X. [Stable carbon isotope characteristics of some woody plants in warm temperate zone]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2000; 11:497-500. [PMID: 11767664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
It was found that the delta 13C values of the foliar, trunk, flower, and fruit of some woody plants in broad-leaved forest in warm temperate zone were affected by many factors, and showed a great interspecific difference and temporal and spatial heterogeneity. The intraspecific variation of delta 13C values was also great, with the order of Vitex negundo var. heterophylla 6.549@1000(-22.226@1000(-)-28.775@1000), Fraxinus rhynchophylla 5.706@1000(-23.687@1000(-)-29.393@1000), Jugans mandshurica 5.229@1000 (-26.146@1000-31.375@1000), Quercus liaotungensis 3.333@1000 (-24.324@1000(-)-27.657@1000), Syringa pekinensis 2.414@1000(-25.655@1000(-)-28.070@1000), and Prunus armeniaca var. ansu 2.296@1000 (-23.436@1000(-)-26.432@1000). Different organs of the same species had different delta 13C values: trunk and root barks had the low, while xylem had the highest delta 13C value. According to the relationship analysis between delta 13C value of Prunus armeniaca var. ansu xylem and environment factors, it was found that delta 13C value was strongly affected by annual mean temperature and followed by annual precipitation, mean temperature and precipitation in growth season.
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Yan C, Fukushi H, Matsudate H, Ishihara K, Yasuda K, Kitagawa H, Yamaguchi T, Hirai K. Seroepidemiological investigation of feline chlamydiosis in cats and humans in Japan. Microbiol Immunol 2000; 44:155-60. [PMID: 10789502 DOI: 10.1111/j.1348-0421.2000.tb02477.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The prevalence of chlamydia antibodies in Japan was investigated in 215 cat sera, consisting of 88 sera of stray cats and 127 sera of pet cats, and 2,184 human sera, taken from 2,003 general persons and 181 small animal clinic veterinarians, by microimmunofluorescence (MIF) testing with Chlamydia psittaci Fe/Pn1 of feline origin and Prk/6BC of avian origin as antigens. The prevalence rates of anti-Fe/Pn1 antibodies were 45.5% in stray cats, 17.3% in pet cats, 1.7% in general persons and 8.8% in small animal clinic veterinarians. The prevalence rates of anti-Prk/6BC antibodies were 51.1% in stray cats, 15.0% in pet cats, 3.1% in general persons and 5.0% in small animal clinic veterinarians. These results suggested that feline chlamydia infection is widely spread in cats especially in stray cats in Japan, and suggested that feline chlamydiosis could be transmitted to people who are in close contact with infected cats.
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Yan C, Dong H, Xu Y, Zhang S, Wang Y, Zhu W, Yao S, Yang Z, Cao J, Liang X. [A cross-sectional study on injuries in the residents of Shijiazhuang city]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2000; 34:206-8. [PMID: 11860930] [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 comprehend current status of injury in the residents of Shijiazhuang city and to lay a foundation for prevention from injury. METHODS A retrospective study on injury in the 21,544 residents of two and six rural villages was conducted by multi-stage stratified sampling. RESULTS Standardized incidence rate of injury was 4.21% in Shijiazhuang city, higher in the rural than in the urban areas and higher in men than in women. The top three causes of injuries were traffic accidents, falls and poisoning. Traffic accidents and poisoning ranked the first place in the urban areas and in the rural areas, respectively. Falls occurred mostly in those aged less than 14 years and more than 60 years. Gas poisoning and traffic accidents occurred more often in those aged 15 - 34 years and traffic accidents ranked the first in the age group of 35 - 59 years old. Standardized mortality rate of injury was 48.78 per 100,000, higher in the rural than in the urban areas. Standardized mortality rate of suicide was the highest with 23.21 per 100,000 in the countryside and that of traffic accidents ranked the next. In average, 22 years of potential life lost, 17 work years of potential life lost and nine valued years of potential life lost for each death were caused by injury. Disability rate caused by injury was 1.1 percent. Direct economic loss for each case with injury cost 679.98 RMB yuan. Incidence rate for traffic accidents ranked the highest and the most severe in all injuries. CONCLUSION Injury has become an important public health problem harmful to the people's health.
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Ikezoe K, Yan C, Momoi T, Imoto C, Minami N, Ariga M, Nihei K, Nonaka I. A novel congenital myopathy with apoptotic changes. Ann Neurol 2000; 47:531-6. [PMID: 10762169] [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
We report on a female child with congenital myopathy with delayed developmental milestones and mental retardation. The most striking pathological finding was the presence of many condensed to fragmented myonuclei. DNA fragmentation was confirmed by the TUNEL method and supported by the ultrastructural characteristics of apoptotic nuclear changes. We also demonstrated immunohistochemically the activation of caspase-3 and caspase-9. This appears to be the first reported case of congenital myopathy with apoptotic process.
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Wang J, Yan C, Deng Z. [Exploration of mechanism of phlegm-syndrome through the metabolism disorder of adhesion molecules]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 2000; 20:296-7. [PMID: 11789270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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Yan C, Chen J, Chen D, Minami M, Pei W, Yin XM, Simon RP. Overexpression of the cell death suppressor Bcl-w in ischemic brain: implications for a neuroprotective role via the mitochondrial pathway. J Cereb Blood Flow Metab 2000; 20:620-30. [PMID: 10724126 DOI: 10.1097/00004647-200003000-00020] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Bcl-w is a newly described cell death suppressor member of the Bcl-2 gene family. As these genes may have a role in the outcome of ischemic brain injury, the regional expression of Bcl-w protein in rat brain was examined at 6 to 72 hours after 90 minutes of transient middle cerebral artery occlusion. Bcl-w protein, although constitutively expressed at low levels in nonischemic brain, was found to be overexpressed in ischemic brain at all time points studied. Up-regulation of Bcl-w protein was particularly abundant in the penumbral region of the cortex and mainly in cells lacking DNA fragmentation. In the cortical penumbra, Bcl-w protein was detected predominantly in neurons and showed mitochondrial localization, as determined using double-label immunohistochemistry. Bcl-w expression was also detectable, to a lesser extent, in reactive astrocytes in the infarct border zone and in microvessel walls in the infarct regions. At the mechanistic level, incubation of isolated brain mitochondria with the addition of recombinant Bax or high concentration of calcium resulted in release of cytochrome c from the mitochondria. In the presence of recombinant Bcl-w protein, however, the release of cytochrome c induced by Bax or calcium was largely inhibited. Further, recombinant Bcl-w protein inhibited calcium-induced loss of mitochondrial transmembrane potential, indicative of permeability transition, in a dose-dependent manner. These results suggest that Bcl-w may be an endogenous neuroprotectant against ischemic neuronal death and that, like its analogues such as Bcl-2 and Bcl-x-long, Bcl-w may achieve this protection via the mitochondrial death-regulatory pathway.
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Abstract
Capillary electrophoretic separations have been investigated for six controlled narcotic analgesic compounds having related structures. Owing to the similar charge-to-mass ratios of these compounds, capillary zone electrophoresis failed to provide a satisfactory separation, whereas a baseline-resolved separation was achieved in 10 min using micellar electrokinetic chromatography. Column efficiencies of 40,000-150,000 plates/m were obtained with a 50 cm long, 50 microm inner diameter (ID) capillary using 50 mM sodium dodecyl sulfate (SDS) in a 50 mM borate solution containing 12% isopropanol. In contrast, separation of this mixture by capillary electrochromatography proved to be significantly superior. The capillary was 15 cm long, with an ID of 75 microm, and was packed with 1.5 microm nonporous octadecyl silica (ODS) particles. The mobile phase consisted of 80% 10 mM tris(hydroxymethyl)aminomethane (Tris) and 20% acetonitrile, and contained 5 mM SDS. A complete separation was obtained in 2.5 min with an efficiency of 250,000-500,000 plates/m.
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Yan C, Li C, Tian F. [Fibronectin induces matrix metalloproteinase-2 expression in ovarian cancer cells]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2000; 22:109-12. [PMID: 11776634] [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 investigate the effects of extracelluar matrix proteins on matrix metalloproteinases (MMPs) expression by cancer cells, and the underlying mechanisms. METHODS Following stimulation of SKOV3 ovarian cancer cells by fibronectin, MMPs secretion and cellular mRNA contents were assayed by gelatin-zymography and RT-PCR, respectively. The activity of MMP-2 promoter was monitored by cellular luciferase activity after the cells were transfected with MMP-2 promoter-luciferase construct. Cellular p53 contents were determined by Western blot analysis. RESULTS Fibronectin (5 micrograms/ml) was found to stimulate the secretion of MMP-2 but not MMP-9 by SKOV3 cells. The stimulation was enhanced with the increase in fibronectin concentration. When SKOV3 cells were treated with 10 micrograms/ml fibronectin for 1 hr, the cellular MMP-2 mRNA dramatically increased. However, with increase in stimulation time, MMP-2 mRNA content decreased. Fibronectin induced an increase in luciferase activity in cells transfected with MMP-2 promoter construct, whilst curcumin (50 mumol/L), a potent transcription factor AP-1 inhibitor, could not block the fibronectin-induced increase in MMP-2 promoter activity. Fibronectin also induced an increase in p53 content of SKOV3 cells. CONCLUSION Fibronectin stimulates ovarian cancer cells to secret MMP-2 via its enhancing effect on MMP-2 promoter activity with resultant increase in MMP-2 transcription. The effect might involve a pathway associated with p53 but independent of AP-1.
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Abstract
Folliculogenesis is regulated by the interplay of extraovarian and intraovarian factors, and the importance of each type of regulation varies depending on the developmental stage of the follicle. Preantral follicle development is regulated predominantly by factors produced locally within the ovary and within the follicle itself. The oocyte has been shown to produce soluble factor(s), which regulate a number of processes in follicular development, including cumulus expansion in the periovulatory period. Members of the TGFbeta superfamily are potent regulators of cell proliferation and differentiation in a number of organ systems, and three members, growth differentiation factor 9 (GDF-9), bone morphogenetic protein 15 (BMP-15) and BMP-6 are expressed by the oocyte and may mediate effects attributed to the oocyte. Based on knockout mouse models BMP-6 does not play an essential role in ovarian function, but GDF-9 is absolutely required for preantral follicle development. GDF-9 also alters the periovulatory expression of granulosa cell genes and stimulates cumulus expansion. Although BMP-15 is expressed identically to GDF-9, its role in regulating ovarian function is still unknown. This review examines the similarities and differences in sequence, expression, and function of the oocyte-expressed TGFbeta family members with respect to regulating folliculogenesis.
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Naltner A, Ghaffari M, Whitsett JA, Yan C. Retinoic acid stimulation of the human surfactant protein B promoter is thyroid transcription factor 1 site-dependent. J Biol Chem 2000; 275:56-62. [PMID: 10617585 DOI: 10.1074/jbc.275.1.56] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Surfactant B (SP-B) is a 79-amino acid peptide critical to postnatal respiratory adaptation. Expression of SP-B by respiratory epithelial cells is regulated by developmental and hormonal influences at the level of gene transcription. Previous studies supported the role of retinoic acids (RA) and their receptors (RARs) in SP-B gene transcription. In the present study, RARalpha was detected in mouse alveolar type II epithelial cells where SP-B is synthesized and processed. Deletion and site-specific mutagenesis analysis identified clustered retinoic acid-responsive element sites in the 5'-flanking enhancer region of the hSP-B gene that bound RARalpha proteins. RAR coactivators ACTR, SRC-1, and transcriptional intermediary factor 2 (TIF2) stimulated human (h) SP-B promoter activity in a dose-dependent fashion in pulmonary adenocarcinoma H441 cells. In addition, an RAR-associated protein, CREB-binding protein (CBP), potentiated the effects of RAR on hSP-B promoter activity in H441 cells. Importantly, RA stimulation of the hSP-B promoter depends on tissue-specific thyroid transcription factor (TTF-1) DNA-binding sites. TTF-1 protein synergistically stimulated the hSP-B promoter with RARalpha, CBP, and nuclear receptor coactivators in H441 cells. In addition, TTF-1 interacted directly with RARalpha and TIF2 in the mammalian two-hybrid system. These findings support a model in which RAR/retinoid X receptor, TTF-1, coactivators, and CBP form a transcription activation complex in the upstream enhancer region of the hSP-B gene.
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Yan C, Wang J, Deng Z. [Current status and prospects of experimental study of psychological stress in traditional Chinese medicine]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 2000; 20:73-4. [PMID: 11783343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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Grover LM, Yan C. Evidence for involvement of group II/III metabotropic glutamate receptors in NMDA receptor-independent long-term potentiation in area CA1 of rat hippocampus. J Neurophysiol 1999; 82:2956-69. [PMID: 10601432 DOI: 10.1152/jn.1999.82.6.2956] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previous studies implicated metabotropic glutamate receptors (mGluRs) in N-methyl-D-aspartate (NMDA) receptor-independent long-term potentiation (LTP) in area CA1 of the rat hippocampus. To learn more about the specific roles played by mGluRs in NMDA receptor-independent LTP, we used whole cell recordings to load individual CA1 pyramidal neurons with a G-protein inhibitor [guanosine-5'-O-(2-thiodiphosphate), GDPbetaS]. Although loading postsynaptic CA1 pyramidal neurons with GDPbetaS significantly reduced G-protein dependent postsynaptic potentials, GDPbetaS failed to prevent NMDA receptor- independent LTP, suggesting that postsynaptic G-protein-dependent mGluRs are not required. We also performed a series of extracellular field potential experiments in which we applied group-selective mGluR antagonists. We had previously determined that paired-pulse facilitation (PPF) was decreased during the first 30-45 min of NMDA receptor-independent LTP. To determine if mGluRs might be involved in these PPF changes, we used a twin-pulse stimulation protocol to measure PPF in field potential experiments. NMDA receptor-independent LTP was prevented by a group II mGluR antagonist [(2S)-alpha-ethylglutamic acid] and a group III mGluR antagonist [(RS)-alpha-cyclopropyl-4-phosphonophenylglycine], but was not prevented by other group II and III mGluR antagonists [(RS)-alpha-methylserine-O-phosphate monophenyl ester or (RS)-alpha-methylserine-O-phosphate]. NMDA receptor-independent LTP was not prevented by either of the group I mGluR antagonists we examined, (RS)-1-aminoindan-1,5-dicarboxylic acid and 7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxylate ethyl ester. The PPF changes which accompany NMDA receptor-independent LTP were not prevented by any of the group-selective mGluR antagonists we examined, even when the LTP itself was blocked. Finally, we found that tetanic stimulation in the presence of group III mGluR antagonists lead to nonspecific potentiation in control (nontetanized) input pathways. Taken together, our results argue against the involvement of postsynaptic group I mGluRs in NMDA receptor-independent LTP. Group II and/or group III mGluRs are required, but the specific details of the roles played by these mGluRs in NMDA receptor-independent LTP are uncertain. Based on the pattern of results we obtained, we suggest that group II mGluRs are required for induction of NMDA receptor-independent LTP, and that group III mGluRs are involved in determining the input specificity of NMDA receptor-independent LTP by suppressing potentiation of nearby, nontetanized synapses.
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Yan W, Ma G, Yan C, Zhou W, Gao H, Li W, Shi N, Wu J, Chen J, Huang K, Yu J, Cui N. [Mechanism of gold solvent extraction from alkaline cyanide solution by surfactant 1 427]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 1999; 19:806-810. [PMID: 15822303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The solvent extraction of gold and the structure of the organic phase were studied by labelled 198Au, 31P NMR and FTIR spectroscopy. The results show that the water content increased with the increase of gold contents in the organic phase. The P=O stretching decreases, while the 31P signal shifts to upfield.
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Dongbao Y, Ross AG, Musheng X, Yuesheng L, Yan C. Highlights on the World Bank Loan Schistosomiasis Control Program in China (1991-1998): a special focus on Hunan Province. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1999; 30:657-63. [PMID: 10928356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
A region-wide sampling survey was conducted in 1995 in order to evaluate the current epidemiological status of schistosomiasis japonica in Hunan Province, China. A total of 45,590 humans and 3,726 domestic animals, from 52 villages, were examined parasitologically and/or serologically for current Schistosoma japonicum infections. In uncontrolled endemic areas (43 villages) the overall human prevalence of S. japonicum was 7.81% across the different geographical subtypes. The geometric mean intensity of infection was 17.71 eggs per gram (epg) among infected individuals and only 1.25 epg in the general population. The bovine prevalence, as determined by the hatching test, was 9.63% in the uncontrolled endemic villages. Only one sero-positive (by indirect hemagglutination assay) child was found among 1,072 children tested aged 10-14 years in the 9 endemic villages under effective control. No infection was confirmed by the Kato-Katz thick smear stool examination. When the results of this survey were compared to those seen at baseline (1989) an overall reduction of 45.65% was seen in the human prevalence but no significant change was apparent in the lake-beach ecotype. Additionally, there was more than a 60% reduction in the prevalence among bovines over the same sampling period. The results demonstrate that the World Bank Loan Schistosomiasis Program was successful in achieving its most basic objectives for this province - to reduce human and bovine infections by 40%.
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Shen X, Yan C, Zhang Y. [Comparison of children's blood lead levels in Shanghai before and after the introduction of lead free gasoline]. ZHONGHUA YI XUE ZA ZHI 1999; 79:739-41. [PMID: 11715519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
OBJECTIVE To determine the blood lead levels of children before and after the introduction of lead free gasoline in Shanghai. METHODS We measured the blood lead levels in 1972 children in Shanghai before the introduction of lead free gasoline in Shanghai. The blood lead levels of those children were re-determined 6 months after the leaded gasoline was phased out. RESULTS After leaded gasoline was phased out, geometric mean of blood lead levels was decreased significantly from 83 micrograms/L to 80 micrograms/L. The prevalence rate of childhood lead poisoning (blood lead level equal to or more than 100 micrograms/L) decreased from 37.8% to 25.7%. CONCLUSIONS The introduction of lead free gasoline could decrease children's blood lead levels in Shanghai. However, the magnitude of decrease is not as great as expected, suggesting that more environmental interventions, such as industry emission control, are needed to prevent childhood lead poisoning.
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Yan C, Han R. Effects of genistein on invasion and matrix metalloproteinase activities of HT1080 human fibrosarcoma cells. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1999; 14:129-33. [PMID: 12903810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Effects of genistein on invasion and matrix metalloproteinase activities were investigated in HT1080 human sarcoma cells. Invasion of HT1080 cells through reconstituted basement membrane was inhibited when the cells were treated with 100 micromol/L and 200 micromol/L genistein. At the same concentrations, genistein not only suppressed latent forms of matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9) to convert into active forms, but also increase dramatically the tissue inhibitor of metalloproteinase (TIMP-1) mRNA contents and reverse the imbalance of MMPs and TIMPs. However, expressions of MMP-2 and MMP-9 were not significantly affected. Suppression of MMP activation and increase of TIMP-1 expression will decrease matrix degradation by MMPs, and consequently inhibit invasions of the cells. These results emphasized the existence of the imbalance between MMPs and TIMPs in tumor invasion and metastasis formation. The value of genistein as a drug for antiinvasion and anti-metastasis chemotherapy was suggested.
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Yan C, Shen X, Zhang Y, Wu S, He J, Zhou J, Zhang Y, Ao L, Wu S, Guo D. [A study on relationship between blood lead level and physical growth and development of babies and young children in Shanghai]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 1999; 33:269-71. [PMID: 11864488] [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 effects of low level lead exposure on physical growth and development in young children. METHODS Blood lead level and indicators for physical growth and development, such as body height and weight, and head and chest circumferences were measured in randomly sampled 1,969 children aged 1 - 6 years in Shanghai. Z scores for these indicators were calculated for each of them based on their age and sex-specific norms for children in urban and suburban Shanghai. And, regression analysis of blood lead level was conducted on them. RESULTS Geometric mean of blood lead level was 0.400 micromol/L in young children of Shanghai, and 744 (37.8%) of 1,969 children were equal to or higher than 0.483 micromol/L. Geometric mean of blood lead level correlated in reverse to the Z scores for their body height, weight and head circumference, even if adjusted for the potential confounding factors. CONCLUSION Low level lead exposure could cause adverse effects on their physical growth and development in young children of Shanghai.
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Guo W, Koropchak JA, Yan C. Sensitive, universal detection for capillary electrochromatography using condensation nucleation light scattering detection. J Chromatogr A 1999; 849:587-97. [PMID: 10457453 DOI: 10.1016/s0021-9673(99)00562-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Condensation nucleation light scattering detection (CNLSD) was coupled with a pressurized capillary electrochromatography (pCEC) system using an electrospray interface. Supplementary pressure from a high-pressure pump was used to stabilize the electrospray and electrochromatography processes. Hydrodynamic injections were made with a 20 nl injection valve, and the inherent dead volume from the valve was successfully minimized, such that plate numbers in the range of 120,000 to 350,000/m were observed. Selectivity tuning using both pressure and voltage with the pressurized capillary electrochromatography system was demonstrated. Good reproducibility, comparable sensitivities for a wide range of compounds, including carbohydrates, and limits of detection down to the 50 ng/ml level, corresponding to 1-2 pg levels, were determined without the need for derivatization, demonstrating that condensation nucleation light scattering detection is a sensitive, universal detection method for pressurized capillary electrochromatography.
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