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Shats M, Punzmann H, Xia H. Capillary rogue waves. PHYSICAL REVIEW LETTERS 2010; 104:104503. [PMID: 20366432 DOI: 10.1103/physrevlett.104.104503] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Indexed: 05/29/2023]
Abstract
We report the first observation of extreme wave events (rogue waves) in parametrically driven capillary waves. Rogue waves are observed above a certain threshold in forcing. Above this threshold, frequency spectra broaden and develop exponential tails. For the first time we present evidence of strong four-wave coupling in nonlinear waves (high tricoherence), which points to modulation instability as the main mechanism in rogue waves. The generation of rogue waves is identified as the onset of a distinct tail in the probability density function of the wave heights. Their probability is higher than expected from the measured wave background.
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102
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Ling H, Wen L, Ji X, Tang Y, He J, Tan H, Xia H, Zhou J, Su Q. Growth inhibitory effect and Chk1-dependent signaling involved in G2/M arrest on human gastric cancer cells induced by diallyl disulfide. Braz J Med Biol Res 2010; 43:271-8. [DOI: 10.1590/s0100-879x2010007500004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 01/19/2010] [Indexed: 11/22/2022] Open
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103
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Wang R, Xia H, Nie LB. Synthesis and crystal structure of a cyanide-bridged one-dimensional nickel complex with trans-Cn-Ni(En)2-CN structure. RUSS J COORD CHEM+ 2009. [DOI: 10.1134/s1070328409100029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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104
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Wang L, Luo HS, Xia H. Sodium butyrate induces human colon carcinoma HT-29 cell apoptosis through a mitochondrial pathway. J Int Med Res 2009; 37:803-11. [PMID: 19589263 DOI: 10.1177/147323000903700323] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Some tumours respond favourably to tumour necrosis factor-alpha (TNF-alpha). Despite this preferential sensitivity, resistance to TNF-alpha remains a clinical problem and more interest is now being focused on finding compounds that induce apoptosis through other pathways. Sodium butyrate (NaBt) has anti-tumour effects on colon cancer cells, inhibiting cell growth and promoting differentiation and apoptosis. In this study we investigated whether NaBt induced apoptosis in the human colon cancer cell line HT-29 and examined the intracellular mechanisms involved. Pre-incubation of cells with NaBt significantly increased apoptosis as measured by fluorescence activated cell sorter analysis and mitochondrial membrane potential determination. This effect could be blocked with the caspase inhibitors, z-VAD-fmk (pan-caspase inhibitor), z-DEVD-fmk (caspase-3 inhibitor) and z-LEHD-fmk (caspase-9 inhibitor), but not with z-IETD-fmk (caspase-8 inhibitor). Enhancement of caspase-3 and caspase-9 activities suggests that NaBt induces apoptosis via mitochondrial pathways not involving TNF-alpha.
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Punzmann H, Shats MG, Xia H. Phase randomization of three-wave interactions in capillary waves. PHYSICAL REVIEW LETTERS 2009; 103:064502. [PMID: 19792572 DOI: 10.1103/physrevlett.103.064502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Indexed: 05/28/2023]
Abstract
We present new experimental results on the transition from coherent-phase to random-phase three-wave interactions in capillary waves under parametric excitation. Above the excitation threshold, coherent wave harmonics spectrally broaden. An increase in the pumping amplitude increases spectral widths of wave harmonics and eventually causes a strong decrease in the degree of the three-wave phase coupling. The results point to the modulation instability of capillary waves, which leads to breaking of continuous waves into ensembles of short-lived wavelets or envelope solitons, as the reason for the phase randomization of three-wave interactions.
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Xia H, Xiao W, Lai MO, Lu L. Facile Synthesis of Novel Nanostructured MnO(2) Thin Films and Their Application in Supercapacitors. NANOSCALE RESEARCH LETTERS 2009; 4:1035-1040. [PMID: 20596390 PMCID: PMC2894141 DOI: 10.1007/s11671-009-9352-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Accepted: 05/14/2009] [Indexed: 05/29/2023]
Abstract
Nanostructured alpha-MnO(2) thin films with different morphologies are grown on the platinum substrates by a facile solution method without any assistance of template or surfactant. Microstructural characterization reveals that morphology evolution from dandelion-like spheres to nanoflakes of the as-grown MnO(2) is controlled by synthesis temperature. The capacitive behavior of the MnO(2) thin films with different morphologies are studied by cyclic voltammetry. The alpha-MnO(2) thin films composed of dandelion-like spheres exhibit high specific capacitance, good rate capability, and excellent long-term cycling stability.
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Tu X, Miao L, Kang Y, Xia H, Tu JW, Wang Q, Tu Q, Wang JM, Hao H. Effects of dl-praeruptorin a on cultured neonatal rat ventricular cardiomyocytes with hypertrophy induced by endothelin-1. ACTA ACUST UNITED AC 2009; 31:231-6. [DOI: 10.1358/mf.2009.31.4.1371199] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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108
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Xia H, Punzmann H, Falkovich G, Shats MG. Turbulence-condensate interaction in two dimensions. PHYSICAL REVIEW LETTERS 2008; 101:194504. [PMID: 19113273 DOI: 10.1103/physrevlett.101.194504] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2008] [Indexed: 05/27/2023]
Abstract
We present experimental results on turbulence generated in thin fluid layers in the presence of a large-scale coherent flow, or a spectral condensate. It is shown that the condensate modifies the third-order velocity moment in a much wider interval of scales than the second one. The modification may include the change of sign of the third moment in the inverse cascade. This observation may help resolve a controversy on the energy flux in mesoscale atmospheric turbulence (10-500 km): to recover a correct energy flux from the third velocity moment one needs first to subtract the coherent flow. We find that the condensate also increases the velocity flatness.
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Zhao Y, Wang S, Xia H, Shang M, Zhao B. OL-002 Microarray-based immunogenesis associated gene expression profiling in osteoarticular tuberculosis cases. Int J Infect Dis 2008. [DOI: 10.1016/s1201-9712(09)60099-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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110
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Tang J, Zeng W, Wang W, Ma B, Liu Y, Li H, Xia H, Li P, Zhu L. Genetic analysis and gene mapping of a rice few-tillering mutant in early backcross populations (Oryza sativa L.). SCIENCE IN CHINA. SERIES C, LIFE SCIENCES 2008; 44:570-5. [PMID: 18763097 DOI: 10.1007/bf02879350] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2001] [Indexed: 11/28/2022]
Abstract
A rice mutant, G069, characteristic of few tiller numbers, was found in anther culture progeny from the F(1) hybrid between an indica-japonica cross, Gui630x02428. The mutant has another two major features: delayed tillering development and yellowing apex and margin on the mature leaves. As a donor parent, G069 was further backcrossed with the recurrent parent,02428, for two turns to develop aBC (2)F(2) population. Genetic analysis in the BC (2)F(2) population showed that the traits of few-tillering and yellowing apex and margin on the mature leaves were controlled by one recessive gene. A pool of equally mixed genomic DNA, from few-tillering individual plants in BC (2)F(2), was constructed to screen polymorphism with simple sequence repeat (SSR) markers in comparison with the 02428 genome. One SSR marker and three restriction fragment length polymorphism (RFLP) markers were found possibly linked with the recessive gene. By using these markers, the gene of few-tillering was mapped on chromosome 2 between RFLP marker C424 and S13984 with a genetic distance of 2.4 cM and 0.6 cM, respectively. The gene is designated ft1.
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Xia H. Enhanced disappearance of dicofol by water hyacinth in water. ENVIRONMENTAL TECHNOLOGY 2008; 29:297-302. [PMID: 18610791 DOI: 10.1080/09593330802099684] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The efficiency and primary mechanism of phytoremediation of water contaminated with dicofol, an organochlorine pesticide, by water hyacinth (Eichhornia crassipes) was investigated. After 10 days of incubation in nutrient solution at 25 +/- 1 degree C, the remaining dicofol which was spiked initially at 1 mg l(-1) was 0.05 and 0.26 mg l(-1) in the non-sterile planted and non-sterile unplanted, 0.07 and 0.31 mg l(-1) in the sterile planted and sterile unplanted treatments, respectively. The half-life of dicofol in nutrient solutions was reduced to 59-68 h in the planted treatments from 118-137 h in the unplanted treatments. The accumulated dicofol in water hyacinth plant decreased by 41-53% after the plant had grown for 7 days in dicofol-free nutrient solution. Two phytoprocesses were found to be most important in the remediation of dicofol contaminated water: (i) uptake, accumulation and phytodegradation of dicofol by the plant, accounted for 50% of the removal of the spiked dicofol, and (ii) microbial degradation associated with the rhizosphere, contributed about 7% to dicofol removal. Water hyacinth may thus be a good candidate for development as a phytoremediation system for dicofol-contaminated water.
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112
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Jiang X, Xia H, Du L, Yang S, Lu G. ASCR-016 Comparison of the effect of soluble TRAIL from progression-elevated gene-3 promoter on EC and ES cells. Reprod Biomed Online 2008. [DOI: 10.1016/s1472-6483(10)61551-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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113
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Xia H, Ma X, Tu Y. Comparison of the relative dissipation rates of endosulfan pesticide residues between oolong and green tea. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2007; 25:70-5. [DOI: 10.1080/02652030701523007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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114
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Shats MG, Xia H, Punzmann H, Falkovich G. Suppression of turbulence by self-generated and imposed mean flows. PHYSICAL REVIEW LETTERS 2007; 99:164502. [PMID: 17995257 DOI: 10.1103/physrevlett.99.164502] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Indexed: 05/25/2023]
Abstract
The first direct experimental evidence of the suppression of quasi-two-dimensional turbulence by mean flows is presented. The flow either is induced externally or appears in the process of spectral condensation due to an inverse cascade in bounded turbulence. The observed suppression of large scales is consistent with an expected reduction in the correlation time of turbulent eddies due to shearing. At high flow velocities, sweeping of the forcing-scale vortices reduces the energy input, leading to a reduction in the turbulence level.
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115
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Xia H, Shats MG, Punzmann H. Strong ExB shear flows in the transport-barrier region in H-mode plasma. PHYSICAL REVIEW LETTERS 2006; 97:255003. [PMID: 17280363 DOI: 10.1103/physrevlett.97.255003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Indexed: 05/13/2023]
Abstract
We report the first experimental observation of stationary zonal flow in the transport-barrier region of the H-mode plasma. Strong peaks in Er shear mark the width of this region. A strong m = n = 0 low-frequency (f < 0.6 kHz) zonal flow is observed in regions of increased Er, suggesting a substantial contribution of zonal flow to the spatial modulation of Er radial profiles. Radial localization of the zonal flow is correlated with a region of zero magnetic shear and low-order (7/5) rational surfaces.
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116
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Wong KK, Maser RS, Sahin E, Bailey ST, Xia H, Ji H, McNamara K, Naylor M, Bronson RT, Ghosh S, Welsh R, DePinho RA. Diminished lifespan and acute stress-induced death in DNA-PKcs-deficient mice with limiting telomeres. Oncogene 2006; 26:2815-21. [PMID: 17072335 DOI: 10.1038/sj.onc.1210099] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An adequate and appropriate response to physiological and pathophysiological stresses is critical for long-term homeostasis and viability of the aging organism. Previous work has pointed to the immune system, telomeres and DNA repair pathways as important and distinct determinants of a normal healthy lifespan. In this study, we explored the genetic interactions of telomeres and DNA-PKcs, a protein involved in non-homologous end-joining (NHEJ) and immune responses, in the context of a key aspect of aging and lifespan--the capacity to mount an acute and appropriate immune-mediated stress response. We observed that the combination of DNA-PKcs deficiency and telomere dysfunction resulted in a shortened lifespan that was reduced further following viral infection or experimental activation of the innate immune response. Analysis of the innate immune response in the DNA-PKcs-deficient mice with short dysfunctional telomeres revealed high basal serum levels of tumor necrosis factor alpha (TNFalpha) and hyper-active cytokine responses upon challenge with polyinosinic-polycytidylic acid (poly-IC). We further show that serum cytokine levels become elevated in telomere dysfunctional mice as a function of age. These results raise speculation that these genetic factors may contribute to misdirected immune responses of the aged under conditions of acute and chronic stress.
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117
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Xia H, Zhao R, Hu W, Li Z, Hu G, Hu F. The factors affecting objective response in patients with advanced malignant tumor treated with H101, an E1B-55kD deleted oncolytic adenovirus. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.13166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
13166 Background: H101 is E1B-55kD deleted oncolytic adenovirus which can selectively replicate in tumor cells. Previous phase I/II clinical trials have shown that H101 has certain anti-tumor effects and is safe when applied to patients by intratumoral injection. The aim of this study is to identify the factors affecting tumor response in patients with advanced malignant tumor treated with H101. Methods: All patients in H101 phase II clinical trial were retrospectively reviewed. They were treated with either H101 alone (group A) or H101 combined with conventional chemotherapy (group B). H101 was administrated by intratumoral injection at the dosage of 5×1011 viral particles, once a day for 5 consecutive days. The objective response was evaluated according to WHO criteria and the adverse events were recorded. All information required for this study was retrieved from the database of H101 phase II clinical trial. Chi square test and stepwise multivariable regression were used for statistic analysis with a significant level of p<0.05. Results: There were 106 evaluable patients in this study, 54 in group A (36 males and 18 females, age: 36–78 years), 52 in group B (35 males and 17 females, age: 18–76 years). The diagnoses of these patients include head & neck cancer (54), breast cancer (13) and others (39). All were in the advanced stage of the disease, and refractory or resistant to chemo and radio therapy. The objective response rate was higher in group B (23.1%) as compared to group A (16.7%). In patients with response (CR or PR), 62.5% of them experienced fever after the injection of H101, in contrast, only 18.9% of the patients without response did so. The difference was statistically significant (p<0.01). In the stepwise multivariable regression analysis, tumor response was used as dependent variable, and the independent variables included demographic data, clinical and pathologic type of the tumor, and treatment regimen. The result revealed that tumor response was positively correlated with the fever after H101 injection (p<0.01). Conclusions: H101 has certain anti-tumor efficacy in patients with advanced malignancies, which might be enhanced by the fever after H101 injection and/or combining with chemotherapy. [Table: see text]
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Shats MG, Xia H, Punzmann H. Spectral condensation of turbulence in plasmas and fluids and its role in low-to-high phase transitions in toroidal plasma. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:046409. [PMID: 15903796 DOI: 10.1103/physreve.71.046409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2004] [Indexed: 05/02/2023]
Abstract
Transitions from turbulence to order are studied experimentally in thin fluid layers and in magnetically confined toroidal plasma. It is shown that turbulence self-organizes through the mechanism of spectral condensation in both systems. The spectral redistribution of the turbulent energy leads to the reduction in the turbulence level, generation of coherent flow, reduction in the particle diffusion, and increase in the system's energy. The higher-order state in the plasma is sustained via the non-local spectral coupling of the linearly unstable spectral range to the large-scale mean flow. Spectral condensation of turbulence is discussed in terms of its role in the low-to-high confinement transitions in toroidal plasma which show similarity with phase transitions.
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Zhao Z, Sevryugina Y, Carpenter MA, Welch D, Xia H. All-Optical Hydrogen-Sensing Materials Based on Tailored Palladium Alloy Thin Films. Anal Chem 2004; 76:6321-6. [PMID: 15516124 DOI: 10.1021/ac0494883] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Optical reflectance measurements were performed to determine the hydrogen response characteristics of 20-nm-thick Pd-Au (Ag) films. The response characteristics displayed a strong dependence on alpha, mixed alpha/beta, and beta Pd-hydride phases formed in the films. The response time peaks in the alpha --> beta phase transition region (1625 s at 0.4% H(2) for Pd(0.94)Ag(0.06) and 405 s at 1% H(2) for Pd(0.94)Au(0.06)), consistent with critical slowing down phenomena. The alpha --> beta phase transition region was shifted and inhibited by changing the alloy element to Au and increasing its corresponding content to 40 atom %, respectively. Initial hydrogen uptake rate measurements determined that, due to the adsorption of ambient background gases, the rate-limiting step for alpha or beta phase PdH formation is dissociative chemisorption of hydrogen for each palladium alloy film. By tuning the alloy content and composition of the palladium films, the surface properties of the film become more receptive toward the rapid detection of hydrogen and a novel hydrogen-sensing material using Pd alloyed with 40 atom % Au is presented.
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120
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Gump J, Finkler I, Xia H, Sooryakumar R, Bresser WJ, Boolchand P. Light-induced giant softening of network glasses observed near the mean-field rigidity transition. PHYSICAL REVIEW LETTERS 2004; 92:245501. [PMID: 15245093 DOI: 10.1103/physrevlett.92.245501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Indexed: 05/24/2023]
Abstract
The longitudinal acoustic (LA) mode of bulk GexSe1-x glasses is examined in Brillouin scattering (BS) over the 0.15<x<1/3 range using near band-gap radiation (lambda=647.1 nm). The LA-mode frequency (nu(LA)) softens with increasing laser power in an athermal and reversible manner by nearly 30% (=Delta nu(LA)/nu(LA)) near x=x(c)=0.19(1) or mean coordination number, r(c)=2+2x(c)=2.38(2), close to the mean-field rigidity percolation transition (r(t)=2.40). BS is a bulk probe of elasticity, and photosoftening is maximized here when network stress is minimized near the elastic phase transition.
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Zhu C, Tian H, Xiong Z, Xia H. Follicle-stimulating hormone (FSH) induced internalization of porcine FSH receptor in cultured porcine granulosa cells and Chinese hamster ovary cells transfected with recombinant porcine FSH receptor cDNA. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 2004; 21:188-90. [PMID: 12539572 DOI: 10.1007/bf02886425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In order to study the fate of human follicle-stimulating hormone (FSH) when hormone binds to its receptor, a quick biochemical method that can differentiate between the surface-bound and internalized hormone was used to determine the internalization induced by FSH in cultured both porcine granulosa cells and Chinese hamster ovary (CHO) cells expressing recombinant porcine FSH receptor. The results showed that FSH was slowly internalized, and the internalized radioactivity (acid resistant) reached a peak 10-12 h after addition of 125I-hFSH. It was suggested that FSHR do not get internalized rapidly under physiological circumstances precisely because the appropriate sequences are absent.
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Xia H, Shats MG. Inverse energy cascade correlated with turbulent-structure generation in toroidal plasma. PHYSICAL REVIEW LETTERS 2003; 91:155001. [PMID: 14611471 DOI: 10.1103/physrevlett.91.155001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2002] [Revised: 08/08/2003] [Indexed: 05/24/2023]
Abstract
We report the first experimental observation of the inverse energy cascade correlated with the generation of large turbulent structures. Spectral energy is nonlinearly transferred from the unstable region of the spectrum into large coherent structures and into broadband turbulence in agreement with theoretical expectations. These results are obtained by producing plasma in the H-1 heliac whose parameters allow a single-field, Hasegawa-Mima-type model to be used for the spectral energy transfer analysis.
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123
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Shats MG, Solomon WM, Xia H. Turbulent transport reduction and randomization of coherent fluctuations by zonal flows in toroidal plasma. PHYSICAL REVIEW LETTERS 2003; 90:125002. [PMID: 12688880 DOI: 10.1103/physrevlett.90.125002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2002] [Indexed: 05/24/2023]
Abstract
Fluctuation-driven particle flux is greatly reduced in the plasma radial region where zonal flows are present in the H-1 toroidal heliac. This occurs without reduction in the fluctuation level. Statistical properties of fluctuations are significantly modified in this region. It is shown that the randomization of phases of coherent structures by zonal flows is responsible for the observed effect. This mechanism of transport reduction complements theoretically predicted random shearing of turbulence by zonal flows and does not require the fluctuations suppression.
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Shimizu Y, Sakai K, Miura T, Narita T, Tsukagoshi H, Satoh Y, Ishikawa S, Morishita Y, Takai S, Miyazaki M, Mori M, Saito H, Xia H, Schwartz LB. Characterization of 'adult-type' mast cells derived from human bone marrow CD34(+) cells cultured in the presence of stem cell factor and interleukin-6. Interleukin-4 is not required for constitutive expression of CD54, Fc epsilon RI alpha and chymase, and CD13 expression is reduced during differentiation. Clin Exp Allergy 2002; 32:872-80. [PMID: 12047434 DOI: 10.1046/j.1365-2222.2002.01373.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND In vitro-derived human mast cells exhibit different properties, depending in part on the source of progenitor cells. Most investigations have used fetal liver, cord blood or peripheral blood. Few have used adult bone marrow. OBJECTIVE Human mast cells derived in vitro from the CD34(+) progenitors in bone marrow and cord blood that had been cultured with recombinant human stem cell factor (rhSCF) and recombinant human interleukin-6 (rhIL-6) were compared. METHODS AND RESULTS After 12 weeks of culture, nearly all of the cells were mast cells, and nearly all of these had cytoplasmic granules containing both tryptase and chymase (MCTC type), stained metachromatically with acidic toluidine blue, and expressed CD117 on the cell surface. Both tryptase protein and mRNA were detected by two weeks of culture. Chymase mRNA and protein were detected at 4 weeks but not at 2 weeks of culture. By 12 weeks, chymase content per cell, measured by ELISA, was significantly higher (P < 0.05) in human bone marrow-derived mast cells (HBMMC) (5.6 +/- 0.9 pg) than in cord blood-derived mast cells (CBMC) (2.4 +/- 0.9 pg), whereas histamine and tryptase levels were not significantly different. Of the cluster designations tested, CD29, CD49d, CD51 and CD61 were strongly expressed on HBMMC. CD54 and Fc epsilon RI alpha also were expressed constitutively. Approximately half of CD34-sorted cells at day 0 were CD13(+) and this diminished as mast cell maturation occurred. Electron microscopy revealed that 12-week-old HBMMC had many secretory granules that contained spherical electron dense cores surrounded by electron lucent space, consistent with previous reports of immature MCTC cells developing in vivo. CONCLUSIONS CD34(+) progenitors of human bone marrow are a rich source of mast cell progenitors capable of expressing granule and surface markers of mature mast cells in the presence of rhSCF and rhIL-6.
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Wang G, Williams G, Xia H, Hickey M, Shao J, Davidson BL, McCray PB. Apical barriers to airway epithelial cell gene transfer with amphotropic retroviral vectors. Gene Ther 2002; 9:922-31. [PMID: 12085240 PMCID: PMC7091907 DOI: 10.1038/sj.gt.3301714] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2001] [Accepted: 02/11/2002] [Indexed: 11/09/2022]
Abstract
Gene transfer to airway epithelia with amphotropic pseudotyped retroviral vectors is inefficient following apical vector application. To better understand this inefficiency, we localized the expression of Pit2, the amphotropic receptor, in polarized human airway epithelia. Pit2 was expressed on both the apical and basolateral surfaces of the cells, suggesting that factors other than receptor abundance may limit apical gene transfer efficiency. Binding studies performed with radiolabeled amphotropic MuLV suggested that the apically applied virus binds to Pit2. Hypothetical barriers to retroviral gene transfer include the apical glycocalyx and other secreted products of epithelia. In this study, we demonstrated that sialic acid, keratan sulfate and collagen type V are present on the apical surface of well-differentiated human airway epithelia. While enzyme treatment reduced the abundance of these components, the treatment also decreased the transepithelial resistance to approximately 35% of the controls, suggesting that the epithelial integrity was impaired. To attain an airway epithelial culture with a modified apical surface and intact epithelial integrity, we utilized 100 mM 2-deoxy-D-glucose, a glycosylation inhibitor, to prevent the glycocalyx from reforming following enzyme treatment. This approach allowed the resistance, but not the apical glycocalyx to recover. Despite this physical modification of the cell surface, the amphotropic retroviral vector failed to transduce airway epithelia following apical application. These results suggest that factors other than apical receptor abundance and the glycocalyx inhibit amphotropic retroviral gene transfer in human airway epithelia.
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