Publications by authors named "Xiangwei Huang"

18 Publications

  • Page 1 of 1

Nomogram to predict survival outcome of patients with veno-arterial extracorporeal membrane oxygenation after refractory cardiogenic shock.

Postgrad Med 2021 May 20:1-10. Epub 2021 May 20.

Department of Critical Care Medicine, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, The Second School of Clinical Medicine, Southern Medical University, Gaozhou, Guangdong, China.

: This study aims to develop a nomogram model to predict the survival of refractory cardiogenic shock (RCS) patients that received veno-arterial extracorporeal membrane oxygenation (VA-ECMO).: A total of 235 and 209 RCS patients were supported with VA-ECMO from January 2018 to December 2019 in Guangdong Provincial People's Hospital, and from January 2020 to December 2020 in four third-grade and class-A hospitals were a development cohort (DC) and validation cohort (VC), respectively. Finally, 137 and 98 patients were included in the DC and VC. Multivariate logistic regression analysis was used to identify variables, and only these independent risk factors were used to establish the nomogram model. The receiver operating characteristic curve (ROC), calibration plot, decision curve, and clinical impact curves were used to evaluate the nomogram's discriminative ability, predictive accuracy, and clinical application value.: Pre-ECMO cardiogenic arrest (pre-ECA), lactate (Lac), inotropic score (IS), and modified nutrition risk in the critically ill score (mNUTRIC score) were incorporated into the nomogram. This showed good discrimination in the DC, with an area under ROC (AUROC) and a 95% confidence interval (CI) of 0.959 (0.911-0.986). The AUROC (95% CI) of the VC was 0.928 (0.858-0.971). The calibration plots of the DC and VC presented good calibration results. The decision curve and clinical impact curve of the nomogram provided improved benefits for RCS patients.: This study established a prediction nomogram composed of pre-ECA, Lac, IS, and mNUTRIC scores that could help clinicians to predict the survival probability at hospital discharge precisely and rapidly for RCS patients that received VA-ECMO.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/00325481.2021.1925562DOI Listing
May 2021

Transport evidence of asymmetric spin-orbit coupling in few-layer superconducting 1T-MoTe.

Nat Commun 2019 05 3;10(1):2044. Epub 2019 May 3.

Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China.

Two-dimensional transition metal dichalcogenides MX (M = W, Mo, Nb, and X = Te, Se, S) with strong spin-orbit coupling possess plenty of novel physics including superconductivity. Due to the Ising spin-orbit coupling, monolayer NbSe and gated MoS of 2H structure can realize the Ising superconductivity, which manifests itself with in-plane upper critical field far exceeding Pauli paramagnetic limit. Surprisingly, we find that a few-layer 1T structure MoTe also exhibits an in-plane upper critical field which goes beyond the Pauli paramagnetic limit. Importantly, the in-plane upper critical field shows an emergent two-fold symmetry which is different from the isotropic in-plane upper critical field in 2H transition metal dichalcogenides. We show that this is a result of an asymmetric spin-orbit coupling in 1T transition metal dichalcogenides. Our work provides transport evidence of a new type of asymmetric spin-orbit coupling in transition metal dichalcogenides which may give rise to novel superconducting and spin transport properties.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-019-09995-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6499809PMC
May 2019

Colossal mid-infrared bulk photovoltaic effect in a type-I Weyl semimetal.

Nat Mater 2019 05 4;18(5):471-475. Epub 2019 Mar 4.

Department of Physics, Boston College, Chestnut Hill, MA, USA.

Broadband, efficient and fast conversion of light to electricity is crucial for sensing and clean energy. The bulk photovoltaic effect (BPVE) is a second-order nonlinear optical effect that intrinsically converts light into electrical current. Here, we demonstrate a large mid-infrared BPVE in microscopic devices of the Weyl semimetal TaAs. This discovery results from combining recent developments in Weyl semimetals, focused-ion beam fabrication and theoretical works suggesting a connection between BPVE and topology. We also present a detailed symmetry analysis that allows us to separate the shift current response from photothermal effects. The magnitude and wavelength range of the assigned shift current may impact optical detectors, clean energy and topology, and demonstrate the utility of Weyl semimetals for practical applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41563-019-0297-4DOI Listing
May 2019

A library of atomically thin metal chalcogenides.

Nature 2018 04 18;556(7701):355-359. Epub 2018 Apr 18.

Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore.

Investigations of two-dimensional transition-metal chalcogenides (TMCs) have recently revealed interesting physical phenomena, including the quantum spin Hall effect, valley polarization and two-dimensional superconductivity , suggesting potential applications for functional devices. However, of the numerous compounds available, only a handful, such as Mo- and W-based TMCs, have been synthesized, typically via sulfurization, selenization and tellurization of metals and metal compounds. Many TMCs are difficult to produce because of the high melting points of their metal and metal oxide precursors. Molten-salt-assisted methods have been used to produce ceramic powders at relatively low temperature and this approach was recently employed to facilitate the growth of monolayer WS and WSe. Here we demonstrate that molten-salt-assisted chemical vapour deposition can be broadly applied for the synthesis of a wide variety of two-dimensional (atomically thin) TMCs. We synthesized 47 compounds, including 32 binary compounds (based on the transition metals Ti, Zr, Hf, V, Nb, Ta, Mo, W, Re, Pt, Pd and Fe), 13 alloys (including 11 ternary, one quaternary and one quinary), and two heterostructured compounds. We elaborate how the salt decreases the melting point of the reactants and facilitates the formation of intermediate products, increasing the overall reaction rate. Most of the synthesized materials in our library are useful, as supported by evidence of superconductivity in our monolayer NbSe and MoTe samples and of high mobilities in MoS and ReS. Although the quality of some of the materials still requires development, our work opens up opportunities for studying the properties and potential application of a wide variety of two-dimensional TMCs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41586-018-0008-3DOI Listing
April 2018

High-quality monolayer superconductor NbSe grown by chemical vapour deposition.

Nat Commun 2017 08 30;8(1):394. Epub 2017 Aug 30.

Centre for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.

The discovery of monolayer superconductors bears consequences for both fundamental physics and device applications. Currently, the growth of superconducting monolayers can only occur under ultrahigh vacuum and on specific lattice-matched or dangling bond-free substrates, to minimize environment- and substrate-induced disorders/defects. Such severe growth requirements limit the exploration of novel two-dimensional superconductivity and related nanodevices. Here we demonstrate the experimental realization of superconductivity in a chemical vapour deposition grown monolayer material-NbSe. Atomic-resolution scanning transmission electron microscope imaging reveals the atomic structure of the intrinsic point defects and grain boundaries in monolayer NbSe, and confirms the low defect concentration in our high-quality film, which is the key to two-dimensional superconductivity. By using monolayer chemical vapour deposited graphene as a protective capping layer, thickness-dependent superconducting properties are observed in as-grown NbSe with a transition temperature increasing from 1.0 K in monolayer to 4.56 K in 10-layer.Two-dimensional superconductors will likely have applications not only in devices, but also in the study of fundamental physics. Here, Wang et al. demonstrate the CVD growth of superconducting NbSe2 on a variety of substrates, making these novel materials increasingly accessible.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-017-00427-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5577275PMC
August 2017

Large-Area and High-Quality 2D Transition Metal Telluride.

Adv Mater 2017 Jan 17;29(3). Epub 2016 Nov 17.

Centre for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.

Large-area and high-quality 2D transition metal tellurides are synthesized by the chemical vapor deposition method. The as-grown WTe maintains two different stacking sequences in the bilayer, where the atomic structure of the stacking boundary is revealed by scanning transmission electron microscopy. The low-temperature transport measurements reveal a novel semimetal-to-insulator transition in WTe layers and an enhanced superconductivity in few-layer MoTe .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/adma.201603471DOI Listing
January 2017

Mechanosensing by the α6-integrin confers an invasive fibroblast phenotype and mediates lung fibrosis.

Nat Commun 2016 08 18;7:12564. Epub 2016 Aug 18.

Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294 USA.

Matrix stiffening is a prominent feature of pulmonary fibrosis. In this study, we demonstrate that matrix stiffness regulates the ability of fibrotic lung myofibroblasts to invade the basement membrane (BM). We identify α6-integrin as a mechanosensing integrin subunit that mediates matrix stiffness-regulated myofibroblast invasion. Increasing α6-expression, specifically the B isoform (α6B), couples β1-integrin to mediate MMP-2-dependent pericellular proteolysis of BM collagen IV, leading to myofibroblast invasion. Human idiopathic pulmonary fibrosis lung myofibroblasts express high levels of α6-integrin in vitro and in vivo. Genetic ablation of α6 in collagen-expressing mesenchymal cells or pharmacological blockade of matrix stiffness-regulated α6-expression protects mice against bleomycin injury-induced experimental lung fibrosis. These findings suggest that α6-integrin is a matrix stiffness-regulated mechanosensitive molecule which confers an invasive fibroblast phenotype and mediates experimental lung fibrosis. Targeting this mechanosensing α6(β1)-integrin offers a novel anti-fibrotic strategy against lung fibrosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/ncomms12564DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4992155PMC
August 2016

Development of a radiofrequency ablation platform in a clinically relevant murine model of hepatocellular cancer.

Cancer Biol Ther 2015 ;16(12):1812-9

a Department of Surgery ; Division of Surgical Oncology; Medical University of South Carolina ; Charleston , SC USA.

RFA is used in treatment of patients with hepatocellular cancer (HCC); however, tumor location and size often limit therapeutic efficacy. The absence of a realistic animal model and a radiofrequency ablation (RFA) suitable for small animals presents significant obstacles in developing new strategies. To establish a realistic RFA platform that allows the development of effective RFA-integrated treatment in an orthotopic murine model of HCC, a human cardiac radiofrequency generator was modified for murine use. Parameters were optimized and RFA was then performed in normal murine livers and HCCs. The effects of RFA were monitored by measuring the ablation zone and transaminases. The survival of tumor-bearing mice with and without RFA was monitored, ablated normal liver and HCCs were evaluated macroscopically and histologically. We demonstrated that tissue-mimicking media was able to optimize RFA parameters. Utilizing this information we performed RFA in normal and HCC-bearing mice. RFA was applied to hepatic parenchyma and completely destroyed small tumors and part of large tumors. Localized healing of the ablation and normalization of transaminases occurred within 7 days post RFA. RFA treatment extended the survival of small tumor-bearing mice. They survived at least 5 months longer than the controls; however, mice with larger tumors only had a slight therapeutic effect after RFA. Collectively, we performed RFA in murine HCCs and observed a significant therapeutic effect in small tumor-bearing mice. The quick recovery of tumor-bearing mice receiving RFA mimics observations in human subjects. This platform provides us a unique opportunity to study RFA in HCC treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/15384047.2015.1095412DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4847992PMC
October 2016

Inhibition of mechanosensitive signaling in myofibroblasts ameliorates experimental pulmonary fibrosis.

J Clin Invest 2013 Mar 22;123(3):1096-108. Epub 2013 Feb 22.

Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294-0006, USA.

Matrix stiffening and myofibroblast resistance to apoptosis are cardinal features of chronic fibrotic diseases involving diverse organ systems. The interactions between altered tissue biomechanics and cellular signaling that sustain progressive fibrosis are not well defined. In this study, we used ex vivo and in vivo approaches to define a mechanotransduction pathway involving Rho/Rho kinase (Rho/ROCK), actin cytoskeletal remodeling, and a mechanosensitive transcription factor, megakaryoblastic leukemia 1 (MKL1), that coordinately regulate myofibroblast differentiation and survival. Both in an experimental mouse model of lung fibrosis and in human subjects with idiopathic pulmonary fibrosis (IPF), we observed activation of the Rho/ROCK pathway, enhanced actin cytoskeletal polymerization, and MKL1 cytoplasmic-nuclear shuttling. Pharmacologic disruption of this mechanotransduction pathway with the ROCK inhibitor fasudil induced myofibroblast apoptosis through a mechanism involving downregulation of BCL-2 and activation of the intrinsic mitochondrial apoptotic pathway. Treatment with fasudil during the postinflammatory fibrotic phase of lung injury or genetic ablation of Mkl1 protected mice from experimental lung fibrosis. These studies indicate that targeting mechanosensitive signaling in myofibroblasts to trigger the intrinsic apoptosis pathway may be an effective approach for treatment of fibrotic disorders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1172/JCI66700DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3582144PMC
March 2013

Matrix stiffness-induced myofibroblast differentiation is mediated by intrinsic mechanotransduction.

Am J Respir Cell Mol Biol 2012 Sep 29;47(3):340-8. Epub 2012 Mar 29.

Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, Tinsley Harrison Tower 437B, 1900 University Blvd., Birmingham, AL 35294, USA.

The mechanical properties of the extracellular matrix have recently been shown to promote myofibroblast differentiation and lung fibrosis. Mechanisms by which matrix stiffness regulates myofibroblast differentiation are not fully understood. The goal of this study was to determine the intrinsic mechanisms of mechanotransduction in the regulation of matrix stiffness-induced myofibroblast differentiation. A well established polyacrylamide gel system with tunable substrate stiffness was used in this study. Megakaryoblastic leukemia factor-1 (MKL1) nuclear translocation was imaged by confocal immunofluorescent microscopy. The binding of MKL1 to the α-smooth muscle actin (α-SMA) gene promoter was quantified by quantitative chromatin immunoprecipitation assay. Normal human lung fibroblasts responded to matrix stiffening with changes in actin dynamics that favor filamentous actin polymerization. Actin polymerization resulted in nuclear translocation of MKL1, a serum response factor coactivator that plays a central role in regulating the expression of fibrotic genes, including α-SMA, a marker for myofibroblast differentiation. Mouse lung fibroblasts deficient in Mkl1 did not respond to matrix stiffening with increased α-SMA expression, whereas ectopic expression of human MKL1 cDNA restored the ability of Mkl1 null lung fibroblasts to express α-SMA. Furthermore, matrix stiffening promoted production and activation of the small GTPase RhoA, increased Rho kinase (ROCK) activity, and enhanced fibroblast contractility. Inhibition of RhoA/ROCK abrogated stiff matrix-induced actin cytoskeletal reorganization, MKL1 nuclear translocation, and myofibroblast differentiation. This study indicates that actin cytoskeletal remodeling-mediated activation of MKL1 transduces mechanical stimuli from the extracellular matrix to a fibrogenic program that promotes myofibroblast differentiation, suggesting an intrinsic mechanotransduction mechanism.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1165/rcmb.2012-0050OCDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3488695PMC
September 2012

Relaxin regulates myofibroblast contractility and protects against lung fibrosis.

Am J Pathol 2011 Dec 6;179(6):2751-65. Epub 2011 Oct 6.

Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.

Myofibroblasts are specialized contractile cells that participate in tissue fibrosis and remodeling, including idiopathic pulmonary fibrosis (IPF). Mechanotransduction, a process by which mechanical stimuli are converted into biochemical signals, regulates myofibroblast differentiation. Relaxin is a peptide hormone that mediates antifibrotic effects through regulation of collagen synthesis and turnover. In this study, we demonstrate enhanced myofibroblast contraction in bleomycin-induced lung fibrosis in mice and in fibroblastic foci of human subjects with IPF, using phosphorylation of the regulatory myosin light chain (MLC(20)) as a biomarker of in vivo cellular contractility. Compared with wild-type mice, relaxin knockout mice express higher lung levels of phospho-MLC(20) and develop more severe bleomycin-induced lung fibrosis. Exogenous relaxin inhibits MLC(20) phosphorylation and bleomycin-induced lung fibrosis in both relaxin knockout and wild-type mice. Ex vivo studies of IPF lung myofibroblasts demonstrate decreases in MLC(20) phosphorylation and reduced contractility in response to relaxin. Characterization of the signaling pathway reveals that relaxin regulates MLC(20) dephosphorylation and lung myofibroblast contraction by inactivating RhoA/Rho-associated protein kinase through a nitric oxide/cGMP/protein kinase G-dependent mechanism. These studies identify a novel antifibrotic role of relaxin involving the inhibition of the contractile phenotype of lung myofibroblasts and suggest that targeting myofibroblast contractility with relaxin-like peptides may be of therapeutic benefit in the treatment of fibrotic lung disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajpath.2011.08.018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3260800PMC
December 2011

KLF6 induces apoptosis in prostate cancer cells through up-regulation of ATF3.

J Biol Chem 2008 Oct 28;283(44):29795-801. Epub 2008 Aug 28.

Department of Pharmaceutical Sciences, College of Pharmacy, North Dakota State University, Fargo, North Dakota 58105, USA.

KLF6 (Kruppel-like factor 6) is a zinc finger transcription factor and a tumor suppressor that is frequently mutated in prostate cancer. KLF6 suppresses tumor growth and induces apoptosis in cancer cells through mechanisms still not defined. Here we show that KLF6 induces apoptosis in prostate cancer cells by ATF3 (activating transcription factor 3) expression. KLF6 binds directly to and activates the ATF3 promoter. ATF3 induced apoptosis when ectopically expressed in cells, whereas knockdown of ATF3 by small interference RNA blocked KLF6-induced apoptosis. KLF6 mutants derived from clinical prostate cancers failed to activate the ATF3 promoter and were unable to induce apoptosis. Furthermore, stress conditions (exposure to staurosporine and hypoxia induced by sodium azide) caused significant increase in ATF3 expression and induced apoptosis, whereas knockdown of KLF6 by small interference RNA blocked the increase of ATF3 as well as the induction of apoptosis in these conditions. Thus, ATF3 is a key mediator of KLF6-induced apoptosis in prostate cancer cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1074/jbc.M802515200DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2573052PMC
October 2008

Developmental expression of amphioxus RACK1.

Sci China C Life Sci 2007 Jun;50(3):329-34

Institute of Developmental Biology, College of Life Science, China.

Vertebrate RACK1 plays a key role in embryonic development. This paper described the cloning, phylogenetic analysis and developmental expression of AmphiRACK1, the RACK1 homologous gene in amphioxus. Phylogenetic analysis indicated that amphioxus RACK1 was located at the base of vertebrate clade. AmphiRACK1 expression in lithium-treated embryos was also examined. During embryonic development, AmphiRACK1 was expressed strongly in cerebral vesicles, neural tubes and somites. In lithium-treated embryos, the segmental expression of AmphiRACK1 in somites became blurry and decreased. Its expression in cerebral vesicles and neural tubes was also weaker or disappeared. In the adult animal, AmphiRACK1 transcripts were detected in the epithelium of midgut diverticulus and gut, wheel organ, gill blood vessels and testis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11427-007-0025-1DOI Listing
June 2007

The expression of AmphiTCTP, a TCTP orthologous gene in amphioxus related to the development of notochord and somites.

Comp Biochem Physiol B Biochem Mol Biol 2007 Jul 3;147(3):460-5. Epub 2007 Mar 3.

Life Science College, The Key Lab of Experimental Teratolog of Ministry of Education, Shandong University, Jinan, China.

The translationally controlled tumor protein (TCTP) is highly conserved and has been widely found in eukaryotic organisms. Here, we report the phylogenetic analysis and developmental expression of AmphiTCTP, a TCTP homologous gene in cephalochordate amphioxus. Phylogenetic analysis indicates that the putative protein of AmphiTCTP is close to its vertebrate orthologs. The mRNA of AmphiTCTP is found in fertilized eggs, early cleavage embryo and most of the early developmental stages by in situ hybridization and RT-PCR, but its expression is not detectable from late cleavage stage to mid-gastrula. The expression of AmphiTCTP in zygotes and early cleavage stages shows that AmphiTCTP may be a maternal gene. From the early neurula stage onward, AmphiTCTP transcript is localized in the presumptive notochord, presomitic mesoderm, and nascent somites. However, its expression is gradually down-regulated after the notochord and somites have been formed. The expression pattern of AmphiTCTP thus coincides with the differentiation of the notochord and somites, this suggests that AmphiTCTP may not be a housekeeping gene and may play an important role in mesoderm development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cbpb.2007.02.012DOI Listing
July 2007

Adenomatous polyposis coli determines sensitivity to histone deacetylase inhibitor-induced apoptosis in colon cancer cells.

Cancer Res 2006 Sep;66(18):9245-51

Department of Pharmaceutical Sciences, College of Pharmacy, North Dakota State University, Fargo, North Dakota 58105, USA.

Inhibitors of histone deacetylases (HDAC) inhibit malignant cell growth and induce apoptosis through unknown mechanisms. Here, we report that the expression status of adenomatous polyposis coli (APC) protein determines the relative sensitivity of colon cancer cells to HDAC inhibitor-induced apoptosis. HCA-7 cells (expressing wild-type beta-catenin and APC proteins) are more sensitive to apoptosis induced by HDAC inhibitors valproic acid (VPA) and suberoylanilide hydroxamic acid than SW620 or HT-29 cells (both expressing mutant APC). When wild-type APC protein was expressed using an inducible expression system, HT-29 cells became sensitive to apoptosis in response to VPA. Conversely, knocking down of endogenous APC protein by small interfering RNA (siRNA) blocked VPA-induced apoptosis in HCA-7 cells. APC mediated VPA-induced apoptosis through down-regulation of survivin. The level of survivin protein decreased in HCA-7 and HT-29/APC cells, but not in SW620 and HT-29/beta-Gal cells after VPA treatment. Whereas knocking down of survivin by siRNA sensitized SW620 cells to VPA-induced apoptosis, overexpression of survivin blocked VPA-induced apoptosis in HCA-7 cells. Down-regulation of survivin transcription occurred through changes in GSK-3beta/beta-catenin/Tcf-4 signaling molecules. VPA also induced proteasome-mediated degradation of survivin protein in HCA-7 cells. Furthermore, we have shown that APC mutation-mediated resistance to apoptosis can be overcome by cotreatment with Flavopiridol, which promotes survivin degradation. These results suggest that APC is a critical determinant of HDAC inhibitor-induced apoptosis in colon cancer cells and survivin is a potential target to enhance apoptotic response to HDAC inhibitors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/0008-5472.CAN-06-0887DOI Listing
September 2006

Expression of a novel somite-formation-related gene, AmphiSom, during amphioxus development.

Dev Genes Evol 2006 Jan 7;216(1):52-5. Epub 2005 Oct 7.

Department of Biology, Shandong University, 27 Shanda nan road, Shandong, Jinan, 250100, People's Republic of China.

A novel gene, AmphiSom, was identified in amphioxus Branchiostoma belcheri tsingtauense. Its sequence and developmental expression pattern were determined. AmphiSom transcripts were first detected in the presomitic mesoderm at the late gastrula stage and reached the highest level in the forming and nascent somites in neurulae. However, the expression of AmphiSom was rapidly down-regulated after somites were formed. It was maintained in the most anterior somite and most posterior somite at neurula stages. By 48 h, AmphiSom transcripts were detected only in the developing tail bud but were no longer detected in 72-h larva. Our data demonstrated that the AmphiSom gene is expressed during the development of somites in amphioxus and could play a role in somite formation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00427-005-0027-6DOI Listing
January 2006

Phylogenetic analysis and developmental expression of thymosin-beta4 gene in amphioxus.

Dev Genes Evol 2005 Jul 24;215(7):364-8. Epub 2005 Mar 24.

Department of Biology, Shandong University, Shandong, Jinan, 250100, People's Republic of China.

Thymosin-beta4 is a highly conserved actin-binding protein that plays an important role in multiple early developmental events and functions in keeping the adult life in vertebrates. Here a cDNA for a thymosin-beta4 gene was isolated from the amphioxus, Branchiostoma belcheri. A molecular phylogenetic tree constructed from the deduced amino acid sequence of the isolated cDNA indicates that this gene belongs to the thymosin-beta4 subfamily, but it is split at the base of the vertebrate gene clade in evolution. In situ hybridization reveals that the expression is detected in the locations homologous to orthologous genes expressing regions of vertebrate embryos and adults, such as the neural plate, neural tube, paraxial mesoderm, differentiating somites, pharynx and gut, midgut diverticulus, blood vessels and body spaces. These results are interpreted to mean that thymosin-beta4 genes might play a conserved role in the patterning of chordate embryos and functions in adults.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00427-005-0481-1DOI Listing
July 2005

Developmental expression of the high mobility group B gene in the amphioxus, Branchiostoma belcheri tsingtauense.

Int J Dev Biol 2005 ;49(1):49-52

Institute of Developmental Biology, Life Science College, Shandong University, Jinan, China.

High-Mobility Group (HMG) B proteins are abundant and highly conserved non-histone proteins, which play an important architectural role in the assembly of nucleoprotein complexes and in the Regulation of transcription. These proteins have also been shown to play key roles during embryonic development and cell differentiation. Here we report a full-length cDNA sequence of the HMG protein, AmphiHMGB from Amphioxus. Sequence analysis indicates that this putative AmphiHMGB protein contains four domains: HMG-box A, HMG-box B, basic region, acidic carboxyl-terminal tail and a linker. Phylogenetic analysis suggests that AmphiHMGB falls outside the vertebrate clade. HMGB gene duplication occurred near the base of the vertebrate gene Clade. The dynamic expression of AmphiHMGB during embryonic development reveals for the first time that it may involve differentiation of neural ectoderm, mesoderm and endoderm in this animal.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1387/ijdb.041915xhDOI Listing
October 2005