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Wang Y, Yin W, Wang Z, Huang J, Pan J, Zhu Y, Xu F, Shao X, Sha J, Cai Y, Liu Q, Dong B, Xue W, Huang Y. Pretreatment plasma fibrinogen as an independent prognostic indicator of prostate cancer patients treated with androgen deprivation therapy. Prostate Cancer Prostatic Dis 2016; 19:209-15. [PMID: 26951714 DOI: 10.1038/pcan.2016.6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 01/13/2016] [Accepted: 01/19/2016] [Indexed: 12/17/2022]
Abstract
BACKGROUND Hyperfibrinogen is thought to be associated with a higher risk of invasion and metastasis, as well as a worse outcome for multiple types of cancer. However, the prognostic significance of plasma fibrinogen has not been investigated in prostate cancer with hormonal therapy. The objective of this study was to evaluate its roles in prostate cancer patients treated with androgen deprivation therapy (ADT). METHODS A total of 290 patients who underwent ADT as first-line therapy for prostate cancer were retrospectively analyzed. The fibrinogen level was measured at the time of diagnosis. Patients were categorized using a cutoff point of 3.225 g l(-1) according to a calculation by the receiver operating curve analysis. Correlations between the fibrinogen and clinical characteristics were analyzed. Meanwhile, univariable and multivariable cox regression analyses were performed to determine the associations of fibrinogen with progression-free survival (PFS), cancer-specific survival (CSS) and overall survival (OS). Prognostic accuracy was evaluated with the Harrell concordance index. RESULTS Compared with patients with a lower fibrinogen level (<3.225 g l(-1)), patients with a higher fibrinogen level were more likely to have higher PSA, Gleason score, risk stratification and incidence of metastasis (P<0.05). Multivariable analyses identified hyperfibrinogen as an independent prognostic factor for PFS (hazard ratio (HR)=2.000, P<0.001), CSS (HR=2.209, P=0.006) and OS (HR=1.965, P=0.009). The final models built by the addition of fibrinogen improved predictive accuracy (c-index: 0.750, 0.799 and 0.767) for PFS, CSS and OS compared with the clinicopathological base models (c-index: 0.730, 0.778 and 0.746), which included Gleason score and metastasis. CONCLUSIONS The pretreatment plasma fibrinogen level was associated with tumor progression and might have a significant role in the prognosis of the prostate cancer patients treated with ADT. Thus, we recommend adding fibrinogen to traditional prognostic model, which may improve its predictive accuracy.
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Liu X, Zhang X, Zhang Z, Chang J, Wu Z, Wang C, Sun Z, Ge X, Geng R, Tang W, Dai C, Lin Y, Sun M, Jia W, Xue W, Hu Y, Li J. 27PD Plasma miRNA-based signatures to predict 3-year postoperative recurrence risk for patients with stage II and III gastric cancer. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv518.02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Huang SX, Liang JL, Sui WG, Lin H, Xue W, Chen JJ, Zhang Y, Gong WW, Dai Y, Ou ML. EDA mutation as a cause of hypohidrotic ectodermal dysplasia: a case report and review of the literature. GENETICS AND MOLECULAR RESEARCH 2015; 14:10344-51. [PMID: 26345974 DOI: 10.4238/2015.august.28.21] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Ectodermal dysplasia (ED) represents a collection of rare disorders that result from a failure of development of the tissues derived from the embryonic ectoderm. ED is often associated with hair, teeth, and skin abnormalities, which are serious conditions affecting the quality of life of the patient. To date, a large number of genes have been found to be associated with this syndrome. Here, we report a patient with hypohidrotic ED (HED) without family history. We identified that this patient's disorder arises from an X-linked HED with a mutation in the EDA gene (G299D) found by whole-exome sequencing. In addition, in this paper we summarize the disease-causing mutations based on current literature. Overall, recent clinical and genetic research involving patients with HED have uncovered a large number of pathogenic mutations in EDA, which might contribute to a full understanding of the function of EDA and the underlying mechanisms of HED caused by EDA mutations.
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Makdessi MJ, Barr TP, Xue W, Strichartz GR. Bupivacaine inhibits endothelin-1-evoked increases in intracellular calcium in model sensory neurons. Acta Anaesthesiol Scand 2015; 59:936-45. [PMID: 25684033 DOI: 10.1111/aas.12481] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 01/03/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND Endothelin-1 (ET-1) induces pain-like behavior in animals and man by activating the Gq protein-coupled receptor endothelin-A (ETA ). Activation of ETA receptors on nociceptor membranes evokes intracellular calcium transients and alters membrane Na(+) and K(+) channel and TRPV1 currents, leading to neuronal hyper-excitability manifested by spontaneous and evoked pain behaviors in vivo. In addition to blocking sodium channels, local anesthetics inhibit the Gq protein-coupled signaling of several inflammatory and pro-algesic mediators. In this study, we aimed to investigate the actions of local anesthetics on ETA -mediated increases in intracellular calcium in ND7/104 model sensory neurons. METHODS Increases in intracellular calcium were measured by the fluorescent indicator fura-2 in a sensory neuron-derived cell line (ND7/104), which endogenously expresses ETA receptors. Effects of lidocaine and bupivacaine, along with their respective membrane-impermeant derivatives QX-314, LEA-123 and LEA-124, on peak calcium responses to ET-1 were measured. RESULTS Bupivacaine suppressed ET-1 responses in a concentration-dependent and non-competitive manner with an IC50 of 3.79 ± 1.63 mM. Bupivacaine (6 mM) reduced the Emax for ET-1 from 50.07 ± 1.91 mM to 27.30 ± 2.92 mM. The actions of bupivacaine occurred quickly and were rapidly reversible. Membrane-impermeant analogs of bupivacaine (LEA-123 and LEA-124, 6 mM) were without effect, as was lidocaine (10 mM) and its quaternary derivative QX-314 (10 mM). CONCLUSION Bupivacaine inhibits ETA -mediated calcium transients at clinically relevant concentrations through an intracellular target. The anti-inflammatory and analgesic actions of bupivacaine may be at least partially due to its inhibitory action on Gq -coupled receptors, including ETA.
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Ding C, Xue W, Tian P, Ding X, Pan X, Xiang H, Tian X, Li Y, Zheng J. Which is more suitable for kidney transplantation at the early post-transplantation phase in China - low dosing or standard dosing of enteric-coated mycophenolate sodium? Int J Clin Pract 2015:10-6. [PMID: 24673714 DOI: 10.1111/ijcp.12401] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
AIMS To investigate the pharmacokinetics of enteric-coated mycophenolate sodium (EC-MPS) and the clinical outcome in kidney transplant recipients in the early post-transplantation phase. Then explain which regimen is more suitable for Chinese renal transplant recipients. METHODOLOGY In total, 60 de novo kidney transplant recipients treated with tacrolimus and steroids were randomised to receive EC-MPS at standard dose (SD; 1440 mg/day; n = 28) or low dose (LD; 1080 mg/day; n = 32). Efficacy parameters, safety and tolerability were assessed over a 6-month study period. Full mycophenolic acid (MPA) areas under the curve (AUCs) were completed on days 3 and 5, whereas a three-point limited sampling strategy (LSS) was utilised for MPA AUC assessments at 2 weeks and months 1, 3 and 6 (the LSS for three-time-point MPA AUC 0-12 h (mg h/l) = 15.99 + 0.87C1 h + 0.68C2 h + 7.85C4 h ; r(2) = 0.8670. RESULTS The mean AUC levels at day 3 and day 5 in the SD group were significantly higher than in the LD group (57.4 mg·h/l vs. 38.2 mg·h/l and 59.3 mg·h/l vs. 44.8 mg·h/l, respectively, p < 0.01). There was a trend for fewer clinically diagnosed acute rejections in the SD group vs. the LD group at 6 months (7.1% vs. 12.5%). This trend was also present when acute rejection was analysed as biopsy-proven cases. There were significantly more acute rejections (all definitions) in patients with MPA AUC levels < 30 mg·h/l compared with those with MPA AUC levels ≥ 30 mg·h/l within 6 months (p < 0.05). Renal function, incidence of infection and haematological disorders were not significantly different in either study group. CONCLUSIONS Early adequate MPA exposure in renal transplant recipients can be achieved with a higher starting dose. In addition, a SD regimen was as well-tolerated as a LD regimen. Furthermore, early adequate MPA exposure significantly lowered the rate of acute rejection without compromising safety and tolerability.
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Soria JC, Boni V, Gazzah A, Holgado E, Even C, Ould-Kaci M, Nazabadioko S, Xue W, Calvo E. A Phase Ib dose escalation study of afatinib in combination with standard-dose cetuximab in patients with advanced solid tumours. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv081.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Leteneux C, Haig J, Xue W, Bhattacharyya S. Ranibizumab for the Treatment of Visual Impairment Due to Myopic Choroidal Neovascularization: Cost-Effectiveness Versus Aflibercept. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2014; 17:A608. [PMID: 27202113 DOI: 10.1016/j.jval.2014.08.2123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Wang P, Xu YS, Dong BC, Xue W, Yu FH. Effects of clonal fragmentation on intraspecific competition of a stoloniferous floating plant. PLANT BIOLOGY (STUTTGART, GERMANY) 2014; 16:1121-6. [PMID: 24661501 DOI: 10.1111/plb.12170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 01/26/2014] [Indexed: 05/11/2023]
Abstract
Disturbance is common and can fragment clones of plants. Clonal fragmentation may affect the density and growth of ramets so that it could alter intraspecific competition. To test this hypothesis, we grew one (low density), five (medium density) or nine (high density) parent ramets of the floating invasive plant Pistia stratiotes in buckets, and newly produced offspring ramets were either severed (with fragmentation) or remained connected to parent ramets (no fragmentation). Increasing density reduced biomass of the whole clone (i.e. parent ramet plus its offspring ramets), showing intense intraspecific competition. Fragmentation decreased biomass of offspring ramets, but increased biomass of parent ramets and the whole clone, suggesting significant resource translocation from parent to offspring ramets when clones were not fragmented. There was no interaction effect of density x fragmentation on biomass of the whole clone, and fragmentation did not affect competition intensity index. We conclude that clonal fragmentation does not alter intraspecific competition between clones of P. stratiotes, but increases biomass production of the whole clone. Thus, fragmentation may contribute to its interspecific competitive ability and invasiveness, and intentional fragmentation should not be recommended as a measure to stop the rapid growth of this invasive species.
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Haig J, Regnier SA, Malcom W, Xue W. Cost-Effectiveness of Ranibizumab Verse Aflibercept in Treatment of Treatment of Visual Impairment Due to Diabetic Macular Oedema (Dmo). VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2014; 17:A609. [PMID: 27202123 DOI: 10.1016/j.jval.2014.08.2132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Liang T, Zhang X, Xue W, Zhao S, Zhang X, Pei J. Curcumin induced human gastric cancer BGC-823 cells apoptosis by ROS-mediated ASK1-MKK4-JNK stress signaling pathway. Int J Mol Sci 2014; 15:15754-65. [PMID: 25198898 PMCID: PMC4200840 DOI: 10.3390/ijms150915754] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 08/26/2014] [Accepted: 09/03/2014] [Indexed: 11/16/2022] Open
Abstract
The signaling mediated by stress-activated MAP kinases (MAPK), c-Jun N-terminal kinase (JNK) has well-established importance in cancer. In the present report, we investigated the effects of curcumin on the signaling pathway in human gastric cancer BGC-823 cells. Curcumin induced reactive oxygen species (ROS) production and BGC-823 cells apoptosis. Inhibition of ROS generation by antioxidant (NAC or Trion) significantly prevented curcumin-mediated apoptosis. Notably, we observed that curcumin activated ASK1, a MAPKKK that is oxidative stress sensitive and responsible to phosphorylation of JNK via triggering cascades, up-regulated an upstream effector of the JNK, MKK4, and phosphorylated JNK protein expression in BGC-823 cells. However, curcumin induced ASK1-MKK4-JNK signaling was attenuated by NAC. All the findings confirm the possibility that oxidative stress-activated ASK1-MKK4-JNK signaling cascade promotes the apoptotic response in curcumin-treated BGC-823 cells.
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Dubowitz N, Xue W, Long Q, Ownby JG, Olson DE, Barb D, Rhee MK, Mohan AV, Watson-Williams PI, Jackson SL, Tomolo AM, Johnson TM, Phillips LS. Aging is associated with increased HbA1c levels, independently of glucose levels and insulin resistance, and also with decreased HbA1c diagnostic specificity. Diabet Med 2014; 31:927-35. [PMID: 24698119 DOI: 10.1111/dme.12459] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 01/06/2014] [Accepted: 03/28/2014] [Indexed: 01/05/2023]
Abstract
AIM To determine whether using HbA1c for screening and management could be confounded by age differences, whether age effects can be explained by unrecognized diabetes and prediabetes, insulin resistance or postprandial hyperglycaemia, and whether the effects of aging have an impact on diagnostic accuracy. METHODS We conducted a cross-sectional analysis in adults without known diabetes in the Screening for Impaired Glucose Tolerance (SIGT) study 2005-2008 (n=1573) and the National Health and Nutrition Examination Survey (NHANES) 2005-2006 (n=1184). RESULTS Both glucose intolerance and HbA(1c) levels increased with age. In univariate analyses including all subjects, HbA(1c) levels increased by 0.93 mmol/mol (0.085%) per 10 years of age in the SIGT study and by 1.03 mmol/mol (0.094%) per 10 years in the NHANES; in both datasets, the HbA(1c) increase was 0.87 mmol/mol (0.08%) per 10 years in subjects without diabetes, and 0.76 mmol/mol (0.07%) per 10 years in subjects with normal glucose tolerance, all P<0.001. In multivariate analyses of subjects with normal glucose tolerance, the relationship between age and HbA(1c) remained significant (P<0.001) after adjustment for covariates including race, BMI, waist circumference, sagittal abdominal diameter, triglyceride/HDL ratio, and fasting and 2-h plasma glucose and other glucose levels, as assessed by an oral glucose tolerance test. In both datasets, the HbA(1c) of an 80-year-old individual with normal glucose tolerance would be 3.82 mmol/mol (0.35%) greater than that of a 30-year-old with normal glucose tolerance, a difference that is clinically significant. Moreover, the specificity of HbA(1c) -based diagnostic criteria for prediabetes decreased substantially with increasing age (P<0.0001). CONCLUSIONS In two large datasets, using different methods to measure HbA(1c), the association of age with higher HbA(1c) levels: was consistent and similar; was both statistically and clinically significant; was unexplained by features of aging; and reduced diagnostic specificity. Age should be taken into consideration when using HbA(1c) for the diagnosis and management of diabetes and prediabetes.
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Han X, Diao L, Xu Y, Xue W, Ouyang T, Li J, Wang T, Fan Z, Fan T, Lin B, Xie Y. Association between the HER2 Ile655Val polymorphism and response to trastuzumab in women with operable primary breast cancer. Ann Oncol 2014; 25:1158-64. [DOI: 10.1093/annonc/mdu111] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Sui W, Cao C, Che W, Chen J, Xue W, Liu P, Guo L, Dai Y. Comparative analyses of histone H3K9 trimethylations in the heart and spleen of normal humans. GENETICS AND MOLECULAR RESEARCH 2014; 13:1697-706. [PMID: 24446338 DOI: 10.4238/2014.january.14.5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The global features of trimethylations of histone 3 at lysine 9 (H3K9me3) have been well studied in recent years; however, most of these studies were performed in mammalian cell lines. In this study, we generated genome-wide maps of H3K9me3 of the human heart and spleen using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) technology. We examined the global patterns of H3K9me3 in both tissues and found that modifications were closely associated with tissue-specific expression, function, and development. In addition, we found that 169 genes displayed significant H3K9me3 differences between the heart and spleen. Among these genes, 64 were heart-H3K9me3-specific, 87 genes were spleen-H3K9me3-specific, and 18 were shared in both heart- and spleen-H3K9me3. In conclusion, we observed significant differences in H3K9me3 in the heart and spleen, which may help to explain epigenetic differences between these tissues. Such novel findings highlight the significance of H3K9me3 as a potential biomarker or promising target for epigenetic-based disease treatment.
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Ke Y, Liu GS, Wang JH, Xue W, Du C, Wu G. Preparation of carboxymethyl cellulose based microgels for cell encapsulation. EXPRESS POLYM LETT 2014. [DOI: 10.3144/expresspolymlett.2014.85] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Liu R, Holck AL, Yang E, Liu C, Xue W. Tropomyosin from tilapia (Oreochromis mossambicus) as an allergen. Clin Exp Allergy 2013; 43:365-77. [PMID: 23414545 DOI: 10.1111/cea.12056] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 09/24/2012] [Accepted: 10/24/2012] [Indexed: 01/01/2023]
Abstract
BACKGROUND Tilapia is among the most common fresh water fish species raised by fish farms and can cause allergic reactions upon ingestion. OBJECTIVE To investigate important allergens in Tilapia (Oreochromis mossambicus). METHODS Allergens were detected using immunoblotting. An important allergen was purified to homogeneity by reversed-phase High Pressure Liquid Chromatography and characterized by enzyme linked immunosorbent assay (ELISA), competitive ELISA, Mass spectrometry (MS), circular dichroism measurements and differential scanning calorimetry. RESULTS By immunoblotting using sera from 10 patients with confirmed tilapia allergy, we identified a number of allergens with apparent molecular weights 114 to 17 kD. All patients produced IgE against a 32 kD allergen, Ore m 4, which was identified by MS as tropomyosin (TM). IgE binding of the pure protein was confirmed by immunoblotting, ELISA and ELISA inhibition. cDNA from tilapia tropomyosin (TM) was sequenced and compared with TMs from other species. The tilapia TM showed 53.5% homology to TM from shrimp. Homology was much higher to human TM isoform 5 (87.7%). CONCLUSION AND CLINICAL RELEVANCE TMs are the major allergens in allergy to crustaceans. Auto-antibodies against human TM isoform 5 have been implicated as a causative agent in inflammatory bowel disease (IBD). Intriguingly, six of the 10 tilapia allergic patients had also been diagnosed with IBD, corroborating a connection between allergy and IBD. To our knowledge, this is the first report of tropomyosin from vertebrates as an allergen.
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Yang Y, Luo L, Xu J, Zhu P, Xue W, Wang J, Li W, Wang M, Cheng K, Liu S, Tang Z, Ring BZ, Su L. Novel EDA p.Ile260Ser mutation linked to non-syndromic hypodontia. J Dent Res 2013; 92:500-6. [PMID: 23625373 DOI: 10.1177/0022034513487557] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Hypodontia, a tooth developmental disease, can affect chewing and pronunciation. Mutations in the ectodysplasin-A (EDA) gene can lead to both X-linked hypohidrotic ectodermal dysplasia (XLHED) and non-syndromic hypodontia (NSH). However, the mechanism by which these 2 related but different disorders are caused by the distinct mutations in EDA is unknown. In this study, we identified a novel missense mutation (c.779 T>G) in a Chinese family with NSH via a direct sequencing approach. This mutation results in an Ile260Ser substitution in the tumor necrosis factor (TNF) homology domain. Homology modeling suggests that this alteration may induce a conformational change in the hydrophobic center of the TNF homology domain. Furthermore, by exploring systematic 3D conformation analysis and calculation of residue relative solvent accessibility (RSA) for all the reported mutated amino acid sites on EDA's TNF homology domain, we found that the site mutations at the interior may be linked to XLHED, while those at the surface are more likely to be associated with NSH. These findings may aid in the discovery of unidentified functionally significant mutation sites in the EDA gene and provide a new way to clarify the mechanisms by which the XLHED and NSH phenotypes arise from mutations in the same gene.
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Liu SY, Shang JX, Wang FH, Liu S, Zhang Y, Li D, Shields D, Xue W, Liu Y, Dang H, Wang S. Oxidation of the two-phase Nb/Nb5Si3 composite: the role of energetics, thermodynamics, segregation, and interfaces. J Chem Phys 2013; 138:014708. [PMID: 23298058 DOI: 10.1063/1.4773447] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Oxidation behavior of the two-phase Nb/Nb(5)Si(3) composite is of significant importance for the potential applications of the composite at high-temperature conditions. We investigate the atomic-scale oxidation mechanism of the Nb/Nb(5)Si(3) composite with first-principles density-functional theory and thermodynamics analysis. In particular, the effects of energetics, thermodynamics, segregation, and interfaces are identified. The clean composite surface is found to be composed of both Nb(110) and Si-terminated Nb(5)Si(3)(001). Energetics and thermodynamics calculations show that, during the oxidation process, the Nb(110) surface is oxidized first, followed by the segregation of niobium of the Nb(5)Si(3)(001) surface and subsequent oxidation of the Nb element of Nb(5)Si(3). High coverage of oxygen results in dissolved oxygen in bulk Nb through the diffusion of oxygen in the surface and at the interface. The theoretical investigation also provides an explanation, at the atomic-scale, for the experimental observation that the oxidation layer is essentially composed of niobium oxide and almost free of silicon. Furthermore, the methodology of this work can be applied to investigations of the oxidation behavior of other two-phase and multi-phase composites.
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Wang JW, Du ZP, Wang WX, Xue W. Anionic surfactant selective electrode for the titrimetric determination of anionic surfactant. RUSS J ELECTROCHEM+ 2012. [DOI: 10.1134/s1023193512090157] [Citation(s) in RCA: 4] [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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Wang W, Xue W, Zhou X, Zhang L, Wu J, Qu L, Jin B, Zhang X, Ma F, Xu X. Effects of candidate genes' polymorphisms on meat quality traits in pigs. ACTA AGR SCAND A-AN 2012. [DOI: 10.1080/09064702.2013.765907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Liu SY, Liu S, Li D, Drwenski TM, Xue W, Dang H, Wang S. Oxidation mechanism of the intermetallic compound Ti3Al from ab initio thermodynamics. Phys Chem Chem Phys 2012; 14:11160-6. [PMID: 22782076 DOI: 10.1039/c2cp40943g] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ab initio density-functional theory and thermodynamics calculations are combined to establish a microscopic mechanism for the oxidation of the α(2)-Ti(3)Al(0001) surface. The surface energies as functions of the chemical potentials, as well as structural relaxations and electronic densities of states, are determined. The surface phase diagram (SPD) of the α(2)-Ti(3)Al(0001) systems with different defects and at various oxygen coverages is constructed. It is found that the Al antisite defect prefers to segregate on the α(2)-Ti(3)Al(0001) surface and oxygen adsorption enhances the segregation with the formation of the surface with three Al antisites per unit surface cell (i.e. the top surface layer is full of Al atoms) at the initial stage of oxidation, accounting for the aluminum selective oxidation observed experimentally. After the initial stage of oxidation, the O-α(2)-Ti(3)Al(0001) system manifests itself with a non-uniform double-phase SPD, suggesting the competition between oxidations of the Al and Ti elements in the oxidation process. This result explains the experimentally observed second regime of oxidation in which both metal elements are oxidized.
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Kitzing T, Xue W, Roessler S, Krasnitz A, Schultz N, Wang X, Wigler M, Lowe S. 584 Cooperating Tumor Suppressor Genes on Chromosome 8p Predict Survival Outcome in Hepatocellular Carcinoma. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71241-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Liao N, Xue W, Yang P, Zhang M. Tensile deformation induced structural rearrangement in amorphous silicon nitride. J STRUCT CHEM+ 2012. [DOI: 10.1134/s0022476612020023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Chen D, Tang Q, Xue W, Wang X. The feasibility of using magnetic nanoparticles modified as gene vector. W INDIAN MED J 2010; 59:300-305. [PMID: 21291111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
OBJECTIVE To evaluate the feasibility of using magnetic nanoparticles (MNPs) as gene vector and the effect of magnetic field on efficiency of transfection. METHODS Magnetic nanoparticles were prepared by controlling some chemical reaction parameters through a partially reduction precipitation method with ferric chloride aqueous solution as precursor material. The surface of particles was modified by polyethyleneimine (PEI) agents. The appearance, the size distribution, structure and phase constitute of MNPs were characterized by Transmission electron microscope (TEM), X-ray diffraction (XRD); the potential of absorbing DNA of MNPs was analysed by electrophoresis. Transfection was determined by delivering reporter gene, PGL2-control encoding luciferase, to different cell lines using MNPs-PLL as vector. The effect of magnetic field on the efficiency of transfection was determined using Nd-Fe-B permanent magnet. RESULTS Foreign gene could be delivered to various cell lines by MNPs-PLL and expressed with high efficiency but the transfection efficiency and time course varied in the different cell lines studied. Magnetic field could enhance the efficiency of transfection by 5-10 fold. CONCLUSION MNPs- PLL can be used as a novel non-viral gene vector in vitro, which offers a basis for gene delivery in vivo.
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124
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Xue W, Pan J, Chen H, Chen Q, Chen Y, Sun J, Xia L, Huang Y. UP-1.019: A New Visualized Puncture System for the PNL Procedure-Initial Experience from Renji Hospital. Urology 2009. [DOI: 10.1016/j.urology.2009.07.466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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125
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Xue W, Chen H, Pan J, Chen Q, Chen Y, Huang Y. UP-1.034: The Application of Flexible Ureteroscope in the Treatment of Ureterointestinal Anastomotic Stricture of Studer Neobladder. Urology 2009. [DOI: 10.1016/j.urology.2009.07.481] [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]
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