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Montinaro S, Luginina M, Garroni S, Orrù R, Delogu F, Bellucci D, Cannillo V, Cao G. Spark plasma sintered CaO-rich bioglass-derived glass-ceramics with different crystallinity ratios: A detailed investigation of their behaviour during biological tests in SBF. Ann Ital Chir 2019. [DOI: 10.1016/j.jeurceramsoc.2018.12.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Wang Y, Wang R, Kim J, Upton MH, Casa D, Gog T, Cao G, Kotliar G, Dean MPM, Liu X. Direct Detection of Dimer Orbitals in Ba_{5}AlIr_{2}O_{11}. PHYSICAL REVIEW LETTERS 2019; 122:106401. [PMID: 30932648 DOI: 10.1103/physrevlett.122.106401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Indexed: 06/09/2023]
Abstract
The electronic states of many Mott insulators, including iridates, are often conceptualized in terms of localized atomic states such as the famous "J_{eff}=1/2 state." Although orbital hybridization can strongly modify such states and dramatically change the electronic properties of materials, probing this process is highly challenging. In this Letter, we directly detect and quantify the formation of dimer orbitals in an iridate material Ba_{5}AlIr_{2}O_{11} using resonant inelastic x-ray scattering. Sharp peaks corresponding to the excitations of dimer orbitals are observed and analyzed by a combination of density functional theory calculations and theoretical simulations based on an Ir-Ir cluster model. Such partially delocalized dimer states lead to a redefinition of the angular momentum of the electrons and changes in the magnetic and electronic behaviors of the material. We use this to explain the reduction of the observed magnetic moment with respect to predictions based on atomic states. This study opens new directions to study dimerization in a large family of materials, including solids, heterostructures, molecules, and transient states.
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Guo T, Cao G, Li Y, Zhang Z, Nör JE, Clarkson BH, Liu J. Signals in Stem Cell Differentiation on Fluorapatite-Modified Scaffolds. J Dent Res 2018; 97:1331-1338. [PMID: 29995454 DOI: 10.1177/0022034518788037] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Previously, we reported that the fluorapatite (FA)-modified polycaprolactone (PCL) nanofiber could be an odontogenic/osteogenic inductive tissue-engineering scaffold by inducing stem cell differentiation and mineralization. The present study aimed to explore which of the signal pathways affected this differentiation and mineralization process. The Human Signal Transduction PathwayFinder RT2 Profiler PCR Array was used to analyze the involvement of potential signal transduction pathways during human dental pulp stem cell (DPSCs) osteogenic differentiation induced by FA-modified PCL nanofiber scaffolds. Based on the results, perturbation studies of the signaling pathways hedgehog, insulin, and Wnt were performed. Moreover, the autophagy process was studied, as indicated by the expression of the microtubule-associated protein 1 light chain 3A/B-II (LC3-II) and the cell osteogenic phenotypic changes. In a comparison of the cells grown on PCL + FA scaffolds and those on PCL-only scaffolds, the transcript expression of BMP2, BMP4, FOXA2, PTCH1, WNT1, and WNT2 (PCR array-labeled signal proteins of the hedgehog pathway); CEBPB, FASN, and HK2 (PCR array-labeled signal proteins of the insulin pathway); and CCND1, JUN, MYC, TCF7, and WISP1 (PCR array-labeled signal proteins of the Wnt pathway) doubled at day 14 when obvious cell osteogenic differentiation occurred. Phenotypically, in all the perturbation groups at day 14, ALP activity, OPN, and autophagy marker LC3-II expression were coincidently decreased. Consistently, no positive alizarin red staining or von Kossa staining was observed in the specimens from these perturbation groups at day 28. The results showed that when obvious cell differentiation occurred at day 14 on PCL + FA control groups, the inhibition of the hedgehog, insulin, and Wnt pathways significantly decreased DPSC osteogenic differentiation and mineralization. The osteogenic differentiation of DPSCs grown on FA-modified PCL scaffolds appeared to be positively modulated by the hedgehog, insulin, and Wnt signal pathways, which were coordinated with and/or mediated by the cell autophagy process.
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Zhao HD, Terzic J, Zheng H, Ni YF, Zhang Y, Ye F, Schlottmann P, Cao G. Decoupling of magnetism and electric transport in single-crystal (Sr 1-x A x ) 2IrO 4 (A = Ca or Ba). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:245801. [PMID: 29722680 DOI: 10.1088/1361-648x/aac23d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We report a systematical structural, transport and magnetic study of Ca or Ba doped Sr2IrO4 single crystals. Isoelectronically substituting Ca2+ (up to 15%) or Ba2+ (up to 4%) ion for the Sr2+ ion provides no additional charge carriers but effectively changes the lattice parameters in Sr2IrO4. In particular, 15% Ca doping considerably reduces the c-axis and the unit cell by nearly 0.45% and 1.00%, respectively. These significant, anisotropic compressions in the lattice parameters conspicuously cause no change in the Néel temperature which remains at 240 K, but drastically reduces the electrical resistivity by up to five orders of magnitude or even precipitates a sharp insulator-to-metal transition at lower temperatures, i.e. the vanishing insulating state accompanies an unchanged Néel temperature in (Sr1-x A x )2IrO4. This observation brings to light an intriguing difference between chemical pressure and applied pressure, the latter of which does suppress the long-range magnetic order in Sr2IrO4. This difference reveals the importance of the Ir1-O2-Ir1 bond angle and homogenous volume compression in determining the magnetic ground state. All results, along with a comparison drawn with results of Tb and La doped Sr2IrO4, underscore that the magnetic transition plays a nonessential role in the formation of the charge gap in the spin-orbit-tuned iridate.
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Zhang M, Zhu X, Xu X, Jin X, Bao H, Dugeer S, Du C, Cao G, Yang Y. Molecular characterization and expression patterns of ghrelin in the reindeer (Rangifer tarandus). Pol J Vet Sci 2018; 21:55-64. [PMID: 29624010 DOI: 10.24425/119022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Ghrelin is a novel growth hormone (GH)-releasing peptide, which has been identified as an endogenous ligand for the GH-sretagogue receptor. The sequence and expression of ghrelin has been determined in many species. In this study, to reveal the molecular characterization and expression patterns of ghrelin in the reindeer (Rangifer tarandus), the full-length DNA and cDNA encoding ghrelin were cloned from reindeer stomach using genome walking and rapid amplification of complementary deoxyribonucleic acid ends (RACE). The expression of ghrelin in almost all tissues was examined by real-time quantitative PCR (RT-qPCR). The 4076 bp amplicon of the ghrelin gene consisting of 4 exons and 3 introns was cloned from reindeer. Results of cDNA cloning and sequence analysis revealed that the full-length ghrelin cDNA was composed of 539 bp that included a 5'-untranslated region (46 bp), an open reading frame (ORF) (351 bp), and a 3'-untranslated region (142 bp). In addition, ghrelin was expressed in the all tissues examined, with the expression in the abomasum significantly higher than that in other tissues (p<0.05), followed by the pancreas, duodenum, testis and oesophagus. The results show that the expression of ghrelin in the reindeer gastrointestinal tract is extensive, suggesting its may have a role in regulating the digestive function.
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Cao G, Zhou G, Hu T, Sun J. 3:36 PM Abstract No. 135 Efficacy and safety of drug-eluting beads transarterial chemoembolization by CalliSpheres ® in 275 hepatocellular carcinoma patients: a result from CTILC study. J Vasc Interv Radiol 2018. [DOI: 10.1016/j.jvir.2018.01.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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Cao G, Terzic J, Zhao HD, Zheng H, De Long LE, Riseborough PS. Electrical Control of Structural and Physical Properties via Strong Spin-Orbit Interactions in Sr_{2}IrO_{4}. PHYSICAL REVIEW LETTERS 2018; 120:017201. [PMID: 29350946 DOI: 10.1103/physrevlett.120.017201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Indexed: 06/07/2023]
Abstract
Electrical control of structural and physical properties is a long-sought, but elusive goal of contemporary science and technology. We demonstrate that a combination of strong spin-orbit interactions (SOI) and a canted antiferromagnetic Mott state is sufficient to attain that goal. The antiferromagnetic insulator Sr_{2}IrO_{4} provides a model system in which strong SOI lock canted Ir magnetic moments to IrO_{6} octahedra, causing them to rigidly rotate together. A novel coupling between an applied electrical current and the canting angle reduces the Néel temperature and drives a large, nonlinear lattice expansion that closely tracks the magnetization, increases the electron mobility, and precipitates a unique resistive switching effect. Our observations open new avenues for understanding fundamental physics driven by strong SOI in condensed matter, and provide a new paradigm for functional materials and devices.
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Hernán Gómez Llambí H, Cao G, Donato M, Suárez D, Ottaviano G, Müller A, Buchholz B, Gelpi R, Otero-Losada M, Milei J. Left ventricular hypertrophy does not prevent heart failure in experimental hypertension. Int J Cardiol 2017; 238:57-65. [PMID: 28410843 DOI: 10.1016/j.ijcard.2017.03.109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Revised: 03/04/2017] [Accepted: 03/24/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Left ventricular hypertrophy (LVH) secondary to hypertension has been accepted to prevent heart failure (HF) while paradoxically increasing cardiovascular morbi-mortality. OBJECTIVES To evaluate whether antihypertensive treatment inhibits LVH, restores beta-adrenergic response and affects myocardial oxidative metabolism. METHODS Ninety spontaneously hypertensive rats (SHR) were distributed into groups and treated (mg/kg, p.o.) with: losartan 30 (L), hydralazine 11 (H), rosuvastatin 10 (R), carvedilol 20 (C). Hypertension control group comprised 18 normotensive rats (Wistar-Kyoto, WKY). Following euthanasia at 16months, contractility was measured in 50% of rats (Langendorff system) before and after isoproterenol (Iso) 10-9M, 10-7M and 10-5M stimulation. Left ventricular weight (LVW) was measured in the remaining hearts, and normalized by BW. Expression of thioredoxin 1 (Trx-1), peroxyredoxin 2 (Prx-2), glutaredoxin 3 (Grx-3), caspase-3 and brain natriuretic peptide (BNP) was determined. RESULTS Systolic blood pressure (mmHg): 154±3 (L), 137±1 (H), 190±3 (R)*, 206±3 (SHR)*, 183±1 (C)**, and 141±1 (WKY) (*p<0.05 vs. L, H, WKY, **p<0.05 vs. L, H, WKY, SHR). LVW/BW was higher in SHR and R (p<0.05). Groups SHR, R and C evidenced baseline contractile depression. Response to Iso 10-5M was similar in WKY and L. Expression of Trx-1, Prx-2 and Grx-3 increased in C, H, R and L (p<0.01). CONCLUSIONS Present findings argue against the traditional idea and support that LVH might not be required to prevent HF. Increased expression of thioredoxins by antihypertensive treatment might be involved in protection from HF.
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Amole C, Ardid M, Arnquist IJ, Asner DM, Baxter D, Behnke E, Bhattacharjee P, Borsodi H, Bou-Cabo M, Campion P, Cao G, Chen CJ, Chowdhury U, Clark K, Collar JI, Cooper PS, Crisler M, Crowder G, Dahl CE, Das M, Fallows S, Farine J, Felis I, Filgas R, Girard F, Giroux G, Hall J, Harris O, Hoppe EW, Jin M, Krauss CB, Laurin M, Lawson I, Leblanc A, Levine I, Lippincott WH, Mamedov F, Maurya D, Mitra P, Nania T, Neilson R, Noble AJ, Olson S, Ortega A, Plante A, Podviyanuk R, Priya S, Robinson AE, Roeder A, Rucinski R, Scallon O, Seth S, Sonnenschein A, Starinski N, Štekl I, Tardif F, Vázquez-Jáuregui E, Wells J, Wichoski U, Yan Y, Zacek V, Zhang J. Dark Matter Search Results from the PICO-60 C_{3}F_{8} Bubble Chamber. PHYSICAL REVIEW LETTERS 2017; 118:251301. [PMID: 28696731 DOI: 10.1103/physrevlett.118.251301] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Indexed: 06/07/2023]
Abstract
New results are reported from the operation of the PICO-60 dark matter detector, a bubble chamber filled with 52 kg of C_{3}F_{8} located in the SNOLAB underground laboratory. As in previous PICO bubble chambers, PICO-60 C_{3}F_{8} exhibits excellent electron recoil and alpha decay rejection, and the observed multiple-scattering neutron rate indicates a single-scatter neutron background of less than one event per month. A blind analysis of an efficiency-corrected 1167-kg day exposure at a 3.3-keV thermodynamic threshold reveals no single-scattering nuclear recoil candidates, consistent with the predicted background. These results set the most stringent direct-detection constraint to date on the weakly interacting massive particle (WIMP)-proton spin-dependent cross section at 3.4×10^{-41} cm^{2} for a 30-GeV c^{-2} WIMP, more than 1 order of magnitude improvement from previous PICO results.
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Cao G, Weber SJ, Martin SO, Malaney TL, Slattery SR, Anderson MH, Sridharan K, Allen TR. In Situ Measurements of Spectral Emissivity of Materials for Very High Temperature Reactors. NUCL TECHNOL 2017. [DOI: 10.13182/nt11-a12317] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Kouyoumdzian NM, Mikusic NR, Cao G, Choi MR, Penna SD, Fernández BE, Toblli JE, Rosón MI. Adverse effects of tempol on hidrosaline balance in rats with acute sodium overload. Biotech Histochem 2017; 91:510-521. [PMID: 27849390 DOI: 10.1080/10520295.2016.1249029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
We studied the effects of tempol, an oxygen radical scavenger, on hydrosaline balance in rats with acute sodium overload. Male rats with free access to water were injected with isotonic (control group) or hypertonic saline solution (0.80 mol/l NaCl) either alone (Na group) or with tempol (Na-T group). Hydrosaline balance was determined during a 90 min experimental period. Protein expressions of aquaporin 1 (AQP1), aquaporin 2 (AQP2), angiotensin II (Ang II) and endothelial nitric oxide synthase (eNOS) were measured in renal tissue. Water intake, creatinine clearance, diuresis and natriuresis increased in the Na group. Under conditions of sodium overload, tempol increased plasma sodium and protein levels and increased diuresis, natriuresis and sodium excretion. Tempol also decreased water intake without affecting creatinine clearance. AQP1 and eNOS were increased and Ang II decreased in the renal cortex of the Na group, whereas AQP2 was increased in the renal medulla. Nonglycosylated AQP1 and eNOS were increased further in the renal cortex of the Na-T group, whereas AQP2 was decreased in the renal medulla and was localized mainly in the cell membrane. Moreover, p47-phox immunostaining was increased in the hypothalamus of Na group, and this increase was prevented by tempol. Our findings suggest that tempol causes hypernatremia after acute sodium overload by inhibiting the thirst mechanism and facilitating diuresis, despite increasing renal eNOS expression and natriuresis.
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Lu X, McNally DE, Moretti Sala M, Terzic J, Upton MH, Casa D, Ingold G, Cao G, Schmitt T. Doping Evolution of Magnetic Order and Magnetic Excitations in (Sr_{1-x}La_{x})_{3}Ir_{2}O_{7}. PHYSICAL REVIEW LETTERS 2017; 118:027202. [PMID: 28128620 DOI: 10.1103/physrevlett.118.027202] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Indexed: 06/06/2023]
Abstract
We use resonant elastic and inelastic x-ray scattering at the Ir-L_{3} edge to study the doping-dependent magnetic order, magnetic excitations, and spin-orbit excitons in the electron-doped bilayer iridate (Sr_{1-x}La_{x})_{3}Ir_{2}O_{7} (0≤x≤0.065). With increasing doping x, the three-dimensional long range antiferromagnetic order is gradually suppressed and evolves into a three-dimensional short range order across the insulator-to-metal transition from x=0 to 0.05, followed by a transition to two-dimensional short range order between x=0.05 and 0.065. Because of the interactions between the J_{eff}=1/2 pseudospins and the emergent itinerant electrons, magnetic excitations undergo damping, anisotropic softening, and gap collapse, accompanied by weakly doping-dependent spin-orbit excitons. Therefore, we conclude that electron doping suppresses the magnetic anisotropy and interlayer couplings and drives (Sr_{1-x}La_{x})_{3}Ir_{2}O_{7} into a correlated metallic state with two-dimensional short range antiferromagnetic order. Strong antiferromagnetic fluctuations of the J_{eff}=1/2 moments persist deep in this correlated metallic state, with the magnon gap strongly suppressed.
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Jude J, White CK, Cao G, Botelho D, Jester W, Panettieri R. Salicylic acid and toluene diisocyanate enhance carbachol-induced bronchoconstriction in human precision-cut lung slices (hPCLS). Toxicol Lett 2016. [DOI: 10.1016/j.toxlet.2016.06.1571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Barone A, Otero-Losada M, Grangeat AM, Cao G, Azzato F, Rodríguez A, Milei J. Ozonetherapy protects from in-stent coronary neointimal proliferation. Role of redoxins. Int J Cardiol 2016; 223:258-261. [PMID: 27541668 DOI: 10.1016/j.ijcard.2016.07.177] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 07/27/2016] [Indexed: 01/16/2023]
Abstract
BACKGROUND In-stent restenosis and poor re-endothelization usually follow percutaneous transluminal coronary angioplasty, even using drug-eluting stents, due to inflammation and oxidative stress. Medical ozone has antioxidant and anti-inflammatory properties and has not been evaluated in this context. OBJECTIVES To evaluate whether ozonotherapy might reduce restenosis following bare metal stents implantation in relation to the redoxin system in pigs. METHODS Twelve male Landrace pigs (51±9kg) underwent percutaneous transluminal circumflex coronary arteries bare metal stent implantation under heparine infusion and fluoroscopical guidance, using standard techniques. Pigs were randomized to ozonetherapy (n=6) or placebo (n=6) treatment. Before stenting (24h) and twice a week for 30days post-stenting, venous blood was collected, ozonized and reinfused. Same procedure was performed in placebo group except for ozonation. Both groups received antiplatelet treatment. Histopathology and immunohistochemistry studies were performed. RESULTS Severe inflammatory reaction and restenosis with increase in the immunohistochemical expression of thioredoxin-1 were observed in placebo group 30days after surgery. Oppositely, ozonetherapy drastically reduced inflammatory reaction and restenosis, and showed no increase in the Trx-1 immunohistochemical expression 30days after surgery. Immunolabeling for Prx-2 was negative in both groups. Ozonated autohemotherapy strikingly reduced restenosis 30days following PTCA with BMS implantation in pigs. CONCLUSIONS Stimulation of the redoxin system by ozone pretreatment might neutralize oxidative damage from the start and increase antioxidative buffering capacity post-injury, reducing further damage and so the demand for antioxidant enzymes. Our interpretation agrees with the ozone oxidative preconditioning mechanism, extensively investigated.
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Souri M, Gruenewald JH, Terzic J, Brill JW, Cao G, Seo SSA. Investigations of metastable Ca2IrO4 epitaxial thin-films: systematic comparison with Sr2IrO4 and Ba2IrO4. Sci Rep 2016; 6:25967. [PMID: 27193161 PMCID: PMC4872129 DOI: 10.1038/srep25967] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 04/26/2016] [Indexed: 11/09/2022] Open
Abstract
We have synthesized thermodynamically metastable Ca2IrO4 thin-films on YAlO3 (110) substrates by pulsed laser deposition. The epitaxial Ca2IrO4 thin-films are of K2NiF4-type tetragonal structure. Transport and optical spectroscopy measurements indicate that the electronic structure of the Ca2IrO4 thin-films is similar to that of Jeff = 1/2 spin-orbit-coupled Mott insulator Sr2IrO4 and Ba2IrO4, with the exception of an increased gap energy. The gap increase is to be expected in Ca2IrO4 due to its increased octahedral rotation and tilting, which results in enhanced electron-correlation, U/W. Our results suggest that the epitaxial stabilization growth of metastable-phase thin-films can be used effectively for investigating layered iridates and various complex-oxide systems.
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Cao G, Cai HX, Liu YF. [Cardiac involvement as the initial clinical presentation in dermatomyositis: one case report]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 2016; 44:354. [PMID: 27112618 DOI: 10.3760/cma.j.issn.0253-3758.2016.04.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Sohn CH, Cho DY, Kuo CT, Sandilands LJ, Qi TF, Cao G, Noh TW. X-ray Absorption Spectroscopy Study of the Effect of Rh doping in Sr2IrO4. Sci Rep 2016; 6:23856. [PMID: 27025538 PMCID: PMC4812298 DOI: 10.1038/srep23856] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 03/16/2016] [Indexed: 11/16/2022] Open
Abstract
We investigate the effect of Rh doping in Sr2IrO4 using X-ray absorption spectroscopy (XAS). We observed appearance of new electron-addition states with increasing Rh concentration (x in Sr2Ir1-xRhxO4) in accordance with the concept of hole doping. The intensity of the hole-induced state is however weak, suggesting weakness of charge transfer (CT) effect and Mott insulating ground states. Also, Ir Jeff = 1/2 upper Hubbard band shifts to lower energy as x increases up to x = 0.23. Combined with optical spectroscopy, these results suggest a hybridisation-related mechanism, in which Rh doping can weaken the (Ir Jeff = 1/2)-(O 2p) orbital hybridisation in the in-planar Rh-O-Ir bond networks.
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Pang H, Shi A, Li M, Xue W, Li Y, Cao G, Yan B, Dong F, Xiao W, He G, Du G, Hu X, Cheng G. Simultaneous Determination of Baicalein and Baicalin in Human Plasma by High Performance Liquid Chromatograph-Tandem Spectrometry and its Application in a Food-Effect Pharmacokinetic Study. Drug Res (Stuttg) 2016; 66:394-401. [PMID: 27022718 DOI: 10.1055/s-0035-1569446] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Velletri T, Xie N, Wang Y, Huang Y, Yang Q, Chen X, Chen Q, Shou P, Gan Y, Cao G, Melino G, Shi Y. P53 functional abnormality in mesenchymal stem cells promotes osteosarcoma development. Cell Death Dis 2016; 7:e2015. [PMID: 26775693 PMCID: PMC4816167 DOI: 10.1038/cddis.2015.367] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 11/13/2015] [Accepted: 11/13/2015] [Indexed: 02/07/2023]
Abstract
It has been shown that p53 has a critical role in the differentiation and functionality of various multipotent progenitor cells. P53 mutations can lead to genome instability and subsequent functional alterations and aberrant transformation of mesenchymal stem cells (MSCs). The significance of p53 in safeguarding our body from developing osteosarcoma (OS) is well recognized. During bone remodeling, p53 has a key role in negatively regulating key factors orchestrating the early stages of osteogenic differentiation of MSCs. Interestingly, changes in the p53 status can compromise bone homeostasis and affect the tumor microenvironment. This review aims to provide a unique opportunity to study the p53 function in MSCs and OS. In the context of loss of function of p53, we provide a model for two sources of OS: MSCs as progenitor cells of osteoblasts and bone tumor microenvironment components. Standing at the bone remodeling point of view, in this review we will first explain the determinant function of p53 in OS development. We will then summarize the role of p53 in monitoring MSC fidelity and in regulating MSC differentiation programs during osteogenesis. Finally, we will discuss the importance of loss of p53 function in tissue microenvironment. We expect that the information provided herein could lead to better understanding and treatment of OS.
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Cao G, Liang X, Zhang J, Zhou Y, Wu J, Zhang Y, Chen Y, Huang J, Liu X, Yu J. Vancomycin serum trough concentration vs. clinical outcome in patients with gram-positive infection: a retrospective analysis. J Clin Pharm Ther 2015; 40:640-4. [PMID: 26383121 DOI: 10.1111/jcpt.12323] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Accepted: 08/12/2015] [Indexed: 10/23/2022]
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Cao G, Nielsen PV, Jensen RL, Heiselberg P, Liu L, Heikkinen J. Protected zone ventilation and reduced personal exposure to airborne cross-infection. INDOOR AIR 2015; 25:307-19. [PMID: 24995998 DOI: 10.1111/ina.12142] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 06/27/2014] [Indexed: 05/05/2023]
Abstract
The main objective of this study was to examine the performance of protected zone ventilation (PZV) and hybrid protected zone ventilation (HPZV) to reduce the direct exposure to exhaled air from others' breathing. Experimental measurements are carried out to test the performance of PZV in a full-scale office room with two breathing thermal manikins. The measurements were performed under three configurations, including two standing manikins at different distances: 0.35, 0.5, and 1.1 m. When the supply air velocity is increased to 4 m/s in the downward plane jet, the dimensionless concentration is 40% lower than for fully mixed ventilation, which can be considered as a measure of protection from the zoning condition. The measurement results showed that in both the PZV and the HPZV system it is possible to decrease the transmission of tracer gas from one manikin to the opposite manikin; therefore, it probably would reduce the risk of air borne cross-infection between two people at the same relative positions. The results suggest that PZV and HPZV may be used to reduce the exposure of people in a protected zone from indoor pollutants emitted in a source zone.
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Torchinsky DH, Chu H, Zhao L, Perkins NB, Sizyuk Y, Qi T, Cao G, Hsieh D. Structural distortion-induced magnetoelastic locking in Sr(2)IrO(4) revealed through nonlinear optical harmonic generation. PHYSICAL REVIEW LETTERS 2015; 114:096404. [PMID: 25793834 DOI: 10.1103/physrevlett.114.096404] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Indexed: 06/04/2023]
Abstract
We report a global structural distortion in Sr_{2}IrO_{4} using spatially resolved optical second and third harmonic generation rotational anisotropy measurements. A symmetry lowering from an I4_{1}/acd to I4_{1}/a space group is observed both above and below the Néel temperature that arises from a staggered tetragonal distortion of the oxygen octahedra. By studying an effective superexchange Hamiltonian that accounts for this lowered symmetry, we find that perfect locking between the octahedral rotation and magnetic moment canting angles can persist even in the presence of large noncubic local distortions. Our results explain the origin of the forbidden Bragg peaks recently observed in neutron diffraction experiments and reconcile the observations of strong tetragonal distortion and perfect magnetoelastic locking in Sr_{2}IrO_{4}.
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Wang Q, Cao Y, Wan XG, Denlinger JD, Qi TF, Korneta OB, Cao G, Dessau DS. Experimental electronic structure of the metallic pyrochlore iridate Bi₂Ir₂O₇. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:015502. [PMID: 25469557 DOI: 10.1088/0953-8984/27/1/015502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Angle-resolved photoemission measurements have been performed on Bi2Ir2O7 single crystals, a metallic end-member of the family of pyrochlore iridates. The density of states, the Fermi surface, and the near-Fermi-level band dispersion in the plane perpendicular to the (1, 1, 1) direction were all measured and found to be in rough overall agreement with our LDA + SOC density functional calculations. Assuming that this same calculation approach will extend to other members of the pyrochlore iridates, the overall agreement we found increases the possibility that some of the novel predicted phases such as quantum spin-ice or Weyl Fermion states will exist in this family of compounds.
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Pogrebna A, Mertelj T, Vujičić N, Cao G, Xu ZA, Mihailovic D. Coexistence of ferromagnetism and superconductivity in iron based pnictides: a time resolved magnetooptical study. Sci Rep 2015; 5:7754. [PMID: 25583548 PMCID: PMC4291556 DOI: 10.1038/srep07754] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/03/2014] [Indexed: 11/18/2022] Open
Abstract
Ferromagnetism and superconductivity are antagonistic phenomena. Their coexistence implies either a modulated ferromagnetic order parameter on a lengthscale shorter than the superconducting coherence length or a weak exchange coupling between the itinerant superconducting electrons and the localized ordered spins. In some iron based pnictide superconductors the coexistence of ferromagnetism and superconductivity has been clearly demonstrated. The nature of the coexistence, however, remains elusive since no clear understanding of the spin structure in the superconducting state has been reached and the reports on the coupling strength are controversial. We show, by a direct optical pump-probe experiment, that the coupling is weak, since the transfer of the excess energy from the itinerant electrons to ordered localized spins is much slower than the electron-phonon relaxation, implying the coexistence without the short-lengthscale ferromagnetic order parameter modulation. Remarkably, the polarization analysis of the coherently excited spin wave response points towards a simple ferromagnetic ordering of spins with two distinct types of ferromagnetic domains.
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Wang JH, Wang L, Cheng HR, Cheng WZ, Rao GP, Cao G, Zhang MQ. First Report of Myrothecium roridum Causing Leaf Spot of Anubias barteri var. nana in Mainland China. PLANT DISEASE 2014; 98:1444. [PMID: 30703966 DOI: 10.1094/pdis-07-14-0709-pdn] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Anubias barteri var. nana (belonging to family Araceae) is one of the most popular ornamental plants for aquaria. It has slow growth and small attractive ornamental leaves. It originated from West Africa, was first described in 1860 by Heinrich Wilhelm Schott (1), and is now commercially planted widely in southern China. A new disease of A. barteri var. nana was observed on leaves. Approximately 30% of the plants in an ornamental nursery in Baiyun district, Gaungzhou, China (113°22'45.15″ E, 23°23'41.15″ N) in July 2013 were found to be infected. The pathogen caused necrotic spots that progressed to form holes on leaves of the infected plants, negatively affecting their ornamental market value. Eventually the diseased plant died. White fungal fruiting bodies and black sporodochia were observed on the surfaces of the symptomatic leaves. A single-spore isolate (myr5) was obtained from the concentric lesions and cultured on potato dextrose agar (PDA). The floccose fungal colonies were white to buff, and black conidiomata were often visible on the surface after 25 days of incubation. The conidia had rounded ends and the average size of conidia was 5.98 ± 0.15 × 2.24 ± 0.08 μm. The rDNA internal transcribed spacer (ITS) region of isolate myr5 was amplified by PCR using ITS1 and ITS4 primer pairs. The amplified product was sequenced and deposited in GenBank (Accession No. KJ572115) and showed 99% identity to Myrothecium roridum isolates BBA 71015 (AJ302001) and BBA 67679 (AJ301995) (unpublished), and 100% identity to the isolate myr2-2 from Dieffenbachia picta 'Camilla' in Taiwan (2). On the basis of morphological and molecular characterization, the fungus causing leaf spot on A. barteri var. nana plants was identified as M. roridum Tode ex Fr (2,3). To confirm the etiology of the disease, Koch's postulates was performed in a greenhouse (28 ± 2°C) using 3-day-old cultures of isolate myr5 and fungal spore suspensions of 1 × 105 conidia ml-1 containing 0.05% of Tween 20. Sixteen healthy leaves, two each from eight plants, were infiltrated on two different parts close to the midribs with 100 μl of the fungal spore using needleless syringes. Water infiltration was used as the control treatment. Water-soaked brown lesions appeared on leaves 7 days after inoculation, followed by the development of dark concentric rings within the necrotic areas on the surface of the inoculated leaves after 15 days of incubation. These symptoms were similar to those in the naturally infected aquarium plants. No symptoms were observed on any of the water micro-infiltrated plants. The fungus was re-isolated from the inoculated plants, but not from control plants. To our knowledge, this is the first report of Myrothecium leaf spot caused by M. roridum on A. barteri var. nana in mainland China. References: (1) W. Crusio. Primitiae Africanae XII 79 (14):1-48, 1979. (2) C. F. Hong et al. Plant Dis. 97:1253, 2013. (3) M. Tulloch. Mycol. Pap. 130:1-42, 1972.
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