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When electric conductors differ from their mirror image, unusual chiral transport coefficients appear that are forbidden in achiral metals, such as a non-linear electric response known as electronic magnetochiral anisotropy (eMChA)1-6. Although chiral transport signatures are allowed by symmetry in many conductors without a centre of inversion, they reach appreciable levels only in rare cases in which an exceptionally strong chiral coupling to the itinerant electrons is present. So far, observations of chiral transport have been limited to materials in which the atomic positions strongly break mirror symmetries. Here, we report chiral transport in the centrosymmetric layered kagome metal CsV3Sb5 observed via second-harmonic generation under an in-plane magnetic field. The eMChA signal becomes significant only at temperatures below [Formula: see text] 35 K, deep within the charge-ordered state of CsV3Sb5 (TCDW ≈ 94 K). This temperature dependence reveals a direct correspondence between electronic chirality, unidirectional charge order7 and spontaneous time-reversal symmetry breaking due to putative orbital loop currents8-10. We show that the chirality is set by the out-of-plane field component and that a transition from left- to right-handed transport can be induced by changing the field sign. CsV3Sb5 is the first material in which strong chiral transport can be controlled and switched by small magnetic field changes, in stark contrast to structurally chiral materials, which is a prerequisite for applications in chiral electronics.
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Fe-based 2D materials exhibit rich chemical compositions and structures, which may imply many unique physical properties and promising applications. However, achieving controllable preparation of ultrathin non-layered FeS crystal on SiO2/Si substrate remains a challenge. Herein, the influence of temperature and molecular sieves is reported on the synthesis of ultrathin FeS nanosheets with a thickness as low as 2.3 nm by molecular sieves-assisted chemical vapor deposition (CVD). The grown FeS nanosheets exhibit a non-layered hexagonal NiAs structure and belong to the P63/mmc space group. The inverted symmetry broken structure is confirmed by the angle-resolved second harmonic generation (SHG) test. In particular, the 2D FeS nanosheets exhibit exceptional metallic behavior, with conductivity up to 1.63 × 106 S m-1 at 300 K for an 8 nm thick sample, which is higher than that of reported 2D metallic materials. This work provides a significant contribution to the synthesis and characterization of 2D non-layered Fe-based materials.
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Investigations of two-dimensional transition-metal chalcogenides (TMCs) have recently revealed interesting physical phenomena, including the quantum spin Hall effect1,2, valley polarization3,4 and two-dimensional superconductivity 5 , suggesting potential applications for functional devices6-10. However, of the numerous compounds available, only a handful, such as Mo- and W-based TMCs, have been synthesized, typically via sulfurization11-15, selenization16,17 and tellurization 18 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 19 and this approach 20 was recently employed to facilitate the growth of monolayer WS2 and WSe2. 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 NbSe2 and MoTe2 samples21,22 and of high mobilities in MoS2 and ReS2. 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.
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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.
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The utilization of anaerobic hydrolysate from agroforestry wastes is limited by dissolved lignin and aromatics, which have received insufficient attention despite their potential as excellent carbon sources for denitrification. This study aims to investigate the influence of hematite on lignin-derived aromatic compounds and denitrifying carbon sources, as well as to identify iron-reducing bacteria that utilize lignin-derived aromatic compounds as electron donors. The findings revealed that hematite facilitated the anaerobic fermentation of plant biomass, resulting in the production of small molecular organic acids. Moreover, biodegradation of lignin-derived aromatic compounds led to the formation of phenolic acids, while an increased generation of denitrifying carbon sources enhanced nitrogen removal efficiency by 13.84 %. Additionally, due to adsorption by hematite and subsequent microbial degradation, there was a significant improvement (40.32%) in color removal rate within denitrification effluent. Notably, Azonexus strains were hypothesized to be involved in Fe(â ¢) reduction coupled with aromatic compounds oxidation.
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Compostos Férricos , Lignina , Lignina/metabolismo , Anaerobiose , Matéria Orgânica Dissolvida , Carbono , Compostos Orgânicos , Desnitrificação , NitrogênioRESUMO
No previous studies have reported the use of a percutaneous suture technique performed by bedside intensivists for site closure during decannulation without direct artery repair in venoarterial extracorporeal membrane oxygenation (VA-ECMO) cases. Thus, the objective of this study was to evaluate the safety and effectiveness of this alternative approach. This retrospective study included 26 consecutive patients who underwent percutaneous VA-ECMO decannulation at Maoming People's Hospital. Bedside percutaneous suture technique performed by intensivists facilitated cannula site closure. Primary outcome was successful closure without additional interventions. Secondary outcomes included procedural time, surgical conversion rate, complications (bleeding, vascular/wound complications, neuropathy, lymphocele), procedure-related death. Follow-up ultrasound were conducted within 6 months after discharge. All patients achieved successful site hemostasis with a median procedural time of 28 minutes. Procedure-related complications included minor bleeding (7.7%), acute lower limb ischemia (15.4%), venous thrombus (11.5%), minor arterial stenosis (7.7%), wound infection (4.2%), delayed healing (15.4%), and wound secondary suturing (6.3%). No procedure-related deaths occurred. Follow-up vascular ultrasound revealed two cases (7.7%) of minor arterial stenosis. The perivascular suture technique may offer intensivists a safe and effective alternative method for access site closure without direct artery suture during ECMO decannulation.
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Oxigenação por Membrana Extracorpórea , Técnicas de Sutura , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Resultado do Tratamento , Remoção de Dispositivo/métodosRESUMO
Background: Bilirubin has both antioxidative and prooxidative properties. The study aimed to explore the relationship between serum bilirubin and hemorrhagic transformation (HT) after intravenous thrombolysis in patients with acute ischemic stroke. Methods: The patients receiving intravenous thrombolysis with alteplase were retrospectively analyzed. HT was defined as new intracerebral hemorrhage in follow-up computed tomography images within 24-36 h after thrombolysis. Symptomatic intracranial hemorrhage (sICH) was defined as HT accompanied by worsening neurological function. Multivariate logistic regression and spline regression models were performed to investigate the relationship between serum bilirubin levels and the risk of HT and sICH. Results: Among 557 included patients, 71 (12.7%) were diagnosed with HT and 28 (5.0%) developed sICH. Patients with HT had significant higher baseline serum total bilirubin, direct bilirubin, and indirect bilirubin levels than those without HT. Multivariable logistic regression analysis indicated that patients with higher serum bilirubin levels, including total bilirubin (OR 1.05, 95% CI 1.01-1.08, p = 0.006), direct bilirubin (OR 1.18, 95% CI 1.05-1.31, p = 0.004), and indirect bilirubin (OR 1.06, 95% CI 1.02-1.10, p = 0.005) had increased risk of HT. Furthermore, multiple-adjusted spline regression models excluded nonlinear association between serum bilirubin levels and HT (p > 0.05 for nonlinearity). Similar results were present between serum bilirubin and sICH. Conclusion: The data showed the positively linearly relationship between serum bilirubin levels and the risk of HT and sICH in patients with acute ischemic stroke undergoing intravenous thrombolysis.
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INTRODUCTION: Sepsis is a life-threatening immune disorder resulting from an dysregulated host response to infection. Adjuvant therapy is a valuable complement to sepsis treatment. Lipoic acid has shown potential in attenuating sepsis-induced immune dysfunction and organ injury in vivo and in vitro studies. However, clinical evidence of lipoic acid injection in sepsis treatment is lacking. Hence, we devised a randomised controlled trial to evaluate the efficacy and safety of lipoic acid injection in improving the prognosis of sepsis or septic shock patients. METHODS AND ANALYSIS: A total of 352 sepsis patients are planned to be recruited from intensive care units (ICUs) at eight tertiary hospitals in China for this trial. Eligible participants will undergo randomisation in a 1:1 ratio, allocating them to either the control group or the experimental group. Both groups received routine care, with the experimental group also receiving lipoic acid injection and the control group receiving placebo. The primary efficacy endpoint is 28-day all-cause mortality. The secondary efficacy endpoints are as follows: ICU and hospital mortality, ICU and hospital stay, new acute kidney injury in ICU, demand and duration of life support, Sequential Organ Failure Assessment (SOFA)/Acute Physiology and Chronic Health Evaluation II (APACHE II) and changes from baseline (ΔSOFA/ΔApache II), arterial blood lactate (LAC) and changes from baseline (ΔLAC), blood procalcitonin, high-sensitivity C-reactive protein, interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) and changes from baseline on day 1 (D1), D3, D5 and D7. Clinical safety will be assessed through analysis of adverse events. ETHICS AND DISSEMINATION: The study was approved by the Ethics Committee of Maoming People's Hospital (approval no. PJ2020MI-019-01). Informed consent will be obtained from the participants or representatives. The findings will be disseminated through academic conferences or journal publications. TRIAL REGISTRATION: ChiCTR2000039023.
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Sepse , Ácido Tióctico , Humanos , Ácido Tióctico/uso terapêutico , Método Simples-Cego , Prognóstico , Unidades de Terapia Intensiva , Sepse/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
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.
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Diferenciação Celular , Matriz Extracelular , Mecanotransdução Celular , Miofibroblastos/fisiologia , Animais , Sequência de Bases , Células Cultivadas , Primers do DNA , Proteínas de Ligação a DNA/metabolismo , Eletroforese em Gel de Poliacrilamida , Proteínas da Matriz Extracelular/metabolismo , Humanos , Camundongos , Camundongos Knockout , Proteínas de Fusão Oncogênica/metabolismo , Fosforilação , TransativadoresRESUMO
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.
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Fibrose Pulmonar Idiopática/prevenção & controle , Miofibroblastos/efeitos dos fármacos , Cadeias Leves de Miosina/metabolismo , Relaxina/farmacologia , Animais , Antibióticos Antineoplásicos/toxicidade , Bleomicina/toxicidade , Células Cultivadas , Feminino , Proteínas de Fluorescência Verde/metabolismo , Humanos , Fibrose Pulmonar Idiopática/fisiopatologia , Mecanotransdução Celular , Camundongos , Camundongos Knockout , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Cadeias Leves de Miosina/antagonistas & inibidores , Fosforilação/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Proteínas RecombinantesRESUMO
BACKGROUND: Extracorporeal membrane oxygenation (ECMO) to support cardiopulmonary resuscitation (CPR), also known as extracorporeal cardiopulmonary resuscitation (ECPR), has shown encouraging results in refractory cardiac arrest (RCA) resuscitation. However, its therapeutic benefits are linked to instant and uninterrupted chest compression (CC), besides early implementation. Mechanical CC can overcome the shortcomings of conventional manual CC, including fatigue and labor consumption, and ensure adequate blood perfusion. A strategy sequentially linking mechanical CPR with ECPR may earn extra favorable outcomes. CASE SERIES: We present a four-case series with ages ranging from 8 to 94 years who presented with prolonged absences of return of spontaneous circulation (ROSC) after CA associated with acute fulminant myocarditis (AFM) and myocardial infarction (MI). All the cases received VA-ECMO (ROTAFLOW, Maquet) assisted ECPR, with intra-aortic balloon pump (IABP) or continuous renal replacement treatment (CRRT) appended if persistently low mean blood pressure (MAP) or ischemic kidney injury occurred. All patients have successfully weaned off ECMO and the assistant life support devices with complete neurological recovery. Three patients were discharged, except the 94-year-old patient who died of irreversible sepsis 20 days after ECMO weaning-off. These encouraging results will hopefully lead to more consideration of this lifesaving therapy model that sequentially integrates mechanical CPR with ECPR to rescue RCA related to reversible cardiac causes. CONCLUSIONS: This successful case series should lead to more consideration of an integrated lifesaving strategy sequentially linking mechanical cardiopulmonary resuscitation with ECPR, as an extra favorable prognosis of refractory cardiac arrest related to this approach can be achieved.
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Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca , Infarto do Miocárdio , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Reanimação Cardiopulmonar/métodos , Criança , Oxigenação por Membrana Extracorpórea/métodos , Parada Cardíaca/etiologia , Parada Cardíaca/terapia , Humanos , Pessoa de Meia-Idade , Prognóstico , Adulto JovemRESUMO
OBJECTIVE: : 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.
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Oxigenação por Membrana Extracorpórea , Estudos de Coortes , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Nomogramas , Estudos Retrospectivos , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapiaRESUMO
BACKGROUND: Ventilator-associated pneumonia is a challenge in critical care and is associated with high mortality and morbidity. Although some consensuses on preventing ventilator-associated pneumonia are reached, it is still somewhat controversial. Meta-analysis has shown that postpyloric tube feeding may reduce the incidences of ventilator-associated pneumonia, which still desires high-quality evidence. This trial aims to evaluate the efficacy and safety profiles of postpyloric tube feeding versus gastric tube feeding. METHODS/DESIGN: In this multicenter, open-label, randomized controlled trial, we will recruit 924 subjects expected to receive mechanical ventilation for no less than 48 h. Subjects on mechanical ventilation will be randomized (1:1) to receive postpyloric or gastric tube feeding and routine preventive measures simultaneously. The primary outcome is the proportion of patients with at least one ventilator-associated pneumonia episode. Adverse events and serious adverse events will be observed closely. DISCUSSION: The VIP study is a large-sample-sized, multicenter, open-label, randomized, parallel-group, controlled trial of postpyloric tube feeding in China and is well-designed based on previous studies. The results of this trial may help to provide evidence-based recommendations for the prevention of ventilator-associated pneumonia. TRIAL REGISTRATION: Chictr.org.cn ChiCTR2100051593 . Registered on 28 September 2021.
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Pneumonia Associada à Ventilação Mecânica , Cuidados Críticos , Nutrição Enteral/efeitos adversos , Nutrição Enteral/métodos , Humanos , Unidades de Terapia Intensiva , Metanálise como Assunto , Estudos Multicêntricos como Assunto , Pneumonia Associada à Ventilação Mecânica/etiologia , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Respiração Artificial/efeitos adversos , Respiração Artificial/métodosRESUMO
The crystal symmetry of a material dictates the type of topological band structures it may host, and therefore symmetry is the guiding principle to find topological materials. Here we introduce an alternative guiding principle, which we call 'quasi-symmetry'. This is the situation where a Hamiltonian has an exact symmetry at lower-order that is broken by higher-order perturbation terms. This enforces finite but parametrically small gaps at some low-symmetry points in momentum space. Untethered from the restraints of symmetry, quasi-symmetries eliminate the need for fine-tuning as they enforce that sources of large Berry curvature will occur at arbitrary chemical potentials. We demonstrate that a quasi-symmetry in the semi-metal CoSi stabilizes gaps below 2 meV over a large near-degenerate plane that can be measured in the quantum oscillation spectrum. The application of in-plane strain breaks the crystal symmetry and gaps the degenerate point, observable by new magnetic breakdown orbits. The quasi-symmetry, however, does not depend on spatial symmetries and hence transmission remains fully coherent. These results demonstrate a class of topological materials with increased resilience to perturbations such as strain-induced crystalline symmetry breaking, which may lead to robust topological applications as well as unexpected topology beyond the usual space group classifications.
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Two-dimensional transition metal dichalcogenides MX2 (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 NbSe2 and gated MoS2 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 1Td structure MoTe2 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 1Td 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.
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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.
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Proteína da Polipose Adenomatosa do Colo/genética , Apoptose/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/farmacologia , Ácido Valproico/farmacologia , Proteína da Polipose Adenomatosa do Colo/antagonistas & inibidores , Proteína da Polipose Adenomatosa do Colo/biossíntese , Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células HT29 , Humanos , Proteínas Inibidoras de Apoptose , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , RNA Interferente Pequeno/genética , Survivina , Fatores de Transcrição TCF/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição , Transfecção , Vorinostat , beta Catenina/metabolismoRESUMO
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.
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Biomarcadores Tumorais/biossíntese , Cordados não Vertebrados/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Notocorda/embriologia , Filogenia , Somitos/metabolismo , Sequência de Aminoácidos , Animais , Biomarcadores Tumorais/genética , Cordados não Vertebrados/citologia , Cordados não Vertebrados/genética , Gástrula/citologia , Gástrula/metabolismo , Hibridização In Situ , Dados de Sequência Molecular , Notocorda/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Somitos/citologia , Proteína Tumoral 1 Controlada por TraduçãoRESUMO
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.
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Cordados não Vertebrados/enzimologia , Receptores de Superfície Celular/genética , Sequência de Aminoácidos , Animais , Cordados não Vertebrados/classificação , Cordados não Vertebrados/genética , Cordados não Vertebrados/crescimento & desenvolvimento , Sequência Conservada , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Humanos , Larva/enzimologia , Dados de Sequência Molecular , Filogenia , Receptores de Quinase C Ativada , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , VertebradosRESUMO
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-NbSe2. Atomic-resolution scanning transmission electron microscope imaging reveals the atomic structure of the intrinsic point defects and grain boundaries in monolayer NbSe2, 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 NbSe2 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.
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Large-area and high-quality 2D transition metal tellurides are synthesized by the chemical vapor deposition method. The as-grown WTe2 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 WTe2 layers and an enhanced superconductivity in few-layer MoTe2 .