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Lei T, Bi Y, Gao MJ, Gao SM, Zhou LL, Zheng HL, Chen XD. HES1 inhibits adipogenesis of porcine mesenchymal stem cells via transcriptional repression of FAD24. Domest Anim Endocrinol 2013; 45:28-32. [PMID: 23611667 DOI: 10.1016/j.domaniend.2013.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 03/16/2013] [Accepted: 03/18/2013] [Indexed: 11/15/2022]
Abstract
Adipogenesis, the development from preadipocytes or mesenchymal stem cells (MSCs) to mature adipocytes, is regulated by a network of signaling pathways and transcription factors. The involvement of Notch signaling and its effector HES1 in adipogenesis has been investigated in several studies with conflicting results. The underlying mechanisms remain unclear because of the lack of information about HES1 target genes during adipocyte differentiation. As a novel gene transiently up-regulated in early adipogenesis, FAD24 functions as a positive regulator of adipocyte differentiation in both preadipocytes and MSCs. In the present study, we report that the expression level of FAD24 is inversely associated with that of HES1 in porcine MSCs after adipogenic induction. Enforced overexpression of HES1 in MSCs during the early stage of adipogenesis significantly repressed the transcription of FAD24 (P < 0.01) and the other pro-adipogenic genes (P < 0.05), resulting in reduced intracellular lipid accumulation. Sequence analysis showed that porcine FAD24 harbors an evolutionarily conserved HES1 binding site in its proximal promoter region. Functional HES1, but not its dominant-negative mutant, markedly reduced the promoter activity of FAD24 (P < 0.01). Site-directed mutation and chromatin immunoprecipitation further confirmed that HES1 inhibits FAD24 transcription by direct binding to the promoter. Taken together, we identified FAD24 as a novel downstream target of HES1 during adipogenesis. Our data suggest that HES1-mediated repression of FAD24 transcription at the early stage of adipocyte differentiation may contribute to the impaired adipogenesis induced by the Notch-HES1 signaling pathway.
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Chen XD, Fu YZ, Wang XR. Local influence measure of zero-inflated generalized Poisson mixture regression models. Stat Med 2013; 32:1294-312. [PMID: 22903860 DOI: 10.1002/sim.5560] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2011] [Accepted: 07/21/2012] [Indexed: 11/07/2022]
Abstract
In many practical applications, count data often exhibit greater or less variability than allowed by the equality of mean and variance, referred to as overdispersion/underdispersion, and there are several reasons that may lead to the overdispersion/underdispersion such as zero inflation and mixture. Moreover, if the count data are distributed as a generalized Poisson or a negative binomial distribution that accommodates extra variation not explained by a simple Poisson or a binomial model, then the dispersion occurs too. In this paper, we deal with a class of two-component zero-inflated generalized Poisson mixture regression models to fit such data and propose a local influence measure procedure for model comparison and statistical diagnostics. At first, we formally develop a general model framework that unifies zero inflation, mixture as well as overdispersion/underdispersion simultaneously, and then we mainly investigate two types of perturbation schemes, the global and individual perturbation schemes, for perturbing various model assumptions and detecting influential observations. Also, we obtain the corresponding local influence measures. Our method is novel for count data analysis and can be used to explore these essential issues such as zero inflation, mixture, and dispersion related to zero-inflated generalized Poisson mixture models. On the basis of the results of model comparison, we could further conduct the sensitivity analysis of perturbation as well as hypothesis test with more accuracy. Finally, we employ here a simulation study and a real example to illustrate the proposed local influence measures.
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Mansouri S, Fu N, Woo MW, Chen XD. Uniform amorphous lactose microspheres formed in simultaneous convective and dehydration antisolvent precipitation under atmospheric conditions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:13772-13776. [PMID: 22950653 DOI: 10.1021/la302301h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A simultaneous convection-dehydration and antisolvent precipitation approach has been shown to produce uniform microsized lactose particles from aqueous droplet at atmospheric pressure. Microparticles with high uniformity having diameters of between 1.0 and 2.4 μm have been obtained. The precipitation of the microparticles is driven by a unique self-assembly mechanism that cannot be fully elucidated by supersaturation alone. Further analysis suggests that structural changes in the solvent/antisolvent mixture, due to hydrophobic hydration, could play a role in the precipitation process observed.
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Liu K, Ying CX, Chen XD, Zhou XY, Guo KY. [A case report of myelodysplastic/myeloproliferative disease unclassifiable with karyotype aberration of trisomy 8 and JAK2 mutation]. ZHONGGUO SHI YAN XUE YE XUE ZA ZHI 2012; 20:1139-1143. [PMID: 23114135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
This study aimed to investigate the relationship between clinical features of myelodysplastic/myeloproliferative disease, unclassifiable (MDS/MPD-U), karyotype of chromosome and JAK2 mutation in 1 case. The clinical features, karyotype and JAK2 mutation of the patient with MDS/MPD-U were studied by means of bone marrow biopsy, karyotype analysis and ARMS-PCR technique. The results indicated that the typical micromegakaryocytes and thrombocytosis, karyotype aberration of trisomy 8 as well as JAK2 V617F mutation were found in this patient. It is concluded that the patient was diagnosed as MDS/MPD-U with trisomy 8 and JAK2 V617F mutation. The data of this patient will provide evidence for studying correlation of chromosome karyotype aberration with JAK2 V617F mutation and for evaluating prognosis of MDS/MPD-U.
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Chen XD, Hu XJ, Ma G, Lin XX. Monozygotic twins discordant for port wine stains support the post-zygotic mutation hypothesis. Clin Genet 2012; 83:397-8. [PMID: 22856353 DOI: 10.1111/j.1399-0004.2012.01926.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 06/02/2012] [Accepted: 06/29/2012] [Indexed: 12/01/2022]
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Zeng YC, Xue M, Chi F, Xu ZG, Fan GL, Fan YC, Zheng MH, Zhong WZ, Wang SL, Zhang ZY, Chen XD, Wu LN, Jin XY, Chen W, Li Q, Zhang XY, Xiao YP, Wu R, Guo QY. Serum levels of selenium in patients with brain metastases from non-small cell lung cancer before and after radiotherapy. Cancer Radiother 2012; 16:179-82. [PMID: 22521871 DOI: 10.1016/j.canrad.2011.11.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 11/07/2011] [Accepted: 11/15/2011] [Indexed: 01/06/2023]
Abstract
PURPOSE This study was to evaluate the influence of radiotherapy on the selenium serum levels of non-small cell cancer patients with brain metastases. PATIENTS AND METHODS This prospective study included 95 non-small cell cancer patients with brain metastases treated by radiotherapy from December 2007 until November 2010. Plasma selenium levels were determined before and at the end of the radiotherapy. Age, body mass index (BMI), prior chemotherapy, pathological type and personal habits (smoking and alcoholism) were recorded for each patient. RESULTS The mean age was 63 years; the mean BMI was 27.6. Seventy-six patients (80%) were non-smokers. Sixty-two patients (65.3%) showed no drinking habits and 8 (8.4%) have no prior chemotherapy. Thirty-nine patients (41.1%) were adenocarcinoma, 51 (53.7%) were squamous cell carcinoma and five (5.3%) were large cell carcinoma. At the beginning of radiotherapy, the mean selenium level for all patients was 90.4 μg/l and after radiation this value dropped to 56.3 μg/l. Multivariate analysis showed statistically significant difference in the plasma selenium concentration before and after radiotherapy for age (P<0.001), BMI (P<0.001), smoking (P<0.001), alcoholism (P<0.001), prior chemotherapy (P<0.001) and pathological type (P<0.001). CONCLUSION Significant reduction in plasma levels of selenium was recorded in patients undergoing radiotherapy, suggesting attention to the nutritional status of this micronutrient and other antioxidant agents.
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Fu YZ, Chen XD. Model selection of generalized partially linear models with missing covariates. J Stat Plan Inference 2012. [DOI: 10.1016/j.jspi.2011.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chen X, Zhao S, Tang X, Ge H, Liu P. Neutralization of mouse interleukin-17 bioactivity inhibits corneal allograft rejection. Mol Vis 2011; 17:2148-56. [PMID: 21850190 PMCID: PMC3156778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2011] [Accepted: 08/05/2011] [Indexed: 11/02/2022] Open
Abstract
PURPOSE To investigate the inhibitory effects of anti-mouse interleukin-17 (IL-17) monoclonal antibody (mAb) in high-responder corneal allograft rejection. METHODS C57BL/6 or BALB/c mice corneal grafts were grafted onto BALB/c hosts. The neutralizing mouse IL-17 antibody and isotype control were injected intraperitoneally immediately after transplantation for experimental treatment. At appropriate times after treatment, recipient grafts were assessed clinically and histologically, and recipient corneal graft- infiltrating cells were detected by immunohistochemistry and quantified by real-time PCR. The cytokine spleen levels of T helper type 1 (Th1), Th2, and Th17 were analyzed by enzyme-linked immunosorbent assay. Flow cytometric analysis was used to evaluate the frequencies of IL-17-producing Th17 cells. RESULTS Neutralization of IL-17 with anti-IL-17 mAb obviously prolonged allograft survival compared to the group that received isotype control. Neovascularizations and inflammatory immune cells in corneal stroma decreased in the allogeneic recipients treated with anti-IL-17 mAb. The mRNA (mRNA) level of graft-infiltrating cells, including neutrophiles, cluster of differentiation 4 (CD4) T cells, and CD8 T cells, decreased dramatically in the IL-17 neutralization group. At days 14 and 42, splenocytes from recipients treated with anti-IL-17 mAb produced significantly less of the pro-inflammatory cytokines interferon-gamma (IFN-γ), IL-12p40, and IL-17 compared to those from control Ig-treated recipients at day 14. However, Th2 cytokine IL-4 and IL-5 production increased, and IL-13 levels were not significantly different among the three groups. IL-6 production was elevated in recipients treated with anti-IL-17 mAb. Anti-IL-17 mAb reduced the percentage of Th17 in CD4+ T cells, but there was no statistical significance between anti-IL-17 mAb and the control group. CONCLUSIONS Neutralization of mouse IL-17 bioactivity with anti-IL-17 mAb improves allogeneic corneal graft survival and inhibits corneal allograft rejection to a certain extent by inhibiting production of graft-infiltrating inflammatory cells and decreasing the secretion of pro-inflammatory cytokines.
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Zhang Y, Lei T, Huang JF, Wang SB, Zhou LL, Yang ZQ, Chen XD. The link between fibroblast growth factor 21 and sterol regulatory element binding protein 1c during lipogenesis in hepatocytes. Mol Cell Endocrinol 2011; 342:41-7. [PMID: 21664250 DOI: 10.1016/j.mce.2011.05.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 05/11/2011] [Accepted: 05/20/2011] [Indexed: 10/18/2022]
Abstract
Recently fibroblast growth factor 21 (FGF21) has been identified as a potent regulator in glucose and lipid homeostasis. Here, we firstly investigated the metabolic role of FGF21 in human liver-derived HepG2 cells, and suggested that overexpression of FGF21 suppressed triglyceride accumulation by inhibiting the transcription of the gene necessary for de novo lipogenesis. The potential mechanism of FGF21 regulating lipogenesis was also explored, which revealed that FGF21 repressed the transcription of sterol regulatory element binding protein 1c (SREBP1c), an essential transcription factor promoting expression of lipogenesis-related genes. Overexpression of FGF21 ameliorated the up-regulation of SREBP1c and fatty acid synthase (FAS) in HepG2 cells elicited by FFAs treatment. Moreover, FGF21 could inhibit the transcriptional levels of the key genes involved in processing and nuclear translocation of SREBP1c, and decrease the protein amount of mature SREBP1c. Unexpectedly, overexpression of SREBP1c in HepG2 cells could also inhibit the endogenous FGF21 transcription. Further experiments demonstrated that SREBP1c could significantly attenuate the promoter activity of FGF21. In conclusion, our data identifies a clear link between FGF21 and SREBP1c during lipogenesis in hepatocyte in culture.
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Chen XD, Wei GY, Zhang JL, Dong YY. Efficient production of glutathione using hydrolyzate of banana peel as novel substrate. KOREAN J CHEM ENG 2011. [DOI: 10.1007/s11814-010-0535-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Gao J, Chen R, Li DH, Jiang L, Ye JC, Ma XC, Chen XD, Xiong QH, Sun HD, Wu T. UV light emitting transparent conducting tin-doped indium oxide (ITO) nanowires. NANOTECHNOLOGY 2011; 22:195706. [PMID: 21430316 DOI: 10.1088/0957-4484/22/19/195706] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Multifunctional single crystalline tin-doped indium oxide (ITO) nanowires with tuned Sn doping levels are synthesized via a vapor transport method. The Sn concentration in the nanowires can reach 6.4 at.% at a synthesis temperature of 840 °C, significantly exceeding the Sn solubility in ITO bulks grown at comparable temperatures, which we attribute to the unique feature of the vapor-liquid-solid growth. As a promising transparent conducting oxide nanomaterial, layers of these ITO nanowires exhibit a sheet resistance as low as 6.4 Ω/[Symbol: see text] and measurements on individual nanowires give a resistivity of 2.4 × 10(-4) Ω cm with an electron density up to 2.6 × 10(20) cm(-3), while the optical transmittance in the visible regime can reach ∼ 80%. Under the ultraviolet excitation the ITO nanowire samples emit blue light, which can be ascribed to transitions related to defect levels. Furthermore, a room temperature ultraviolet light emission is observed in these ITO nanowires for the first time, and the exciton-related radiative process is identified by using temperature-dependent photoluminescence measurements.
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Chen XD, Tang NS. Bayesian analysis of semiparametric reproductive dispersion mixed-effects models. Comput Stat Data Anal 2010. [DOI: 10.1016/j.csda.2010.03.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Chen XD, Tang NS, Wang XR. Influence Diagnostics of Semiparametric Nonlinear Reproductive Dispersion Models. COMMUN STAT-THEOR M 2010. [DOI: 10.1080/03610920903171838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Kresnowati MTAP, Forde GM, Chen XD. Model-based analysis and optimization of bioreactor for hematopoietic stem cell cultivation. Bioprocess Biosyst Eng 2010; 34:81-93. [PMID: 20652600 DOI: 10.1007/s00449-010-0449-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Accepted: 06/24/2010] [Indexed: 10/19/2022]
Abstract
One of the problems to be solved in attaining the full potentials of hematopoietic stem cell (HSC) applications is the limited availability of the cells. Growing HSCs in a bioreactor offers an alternative solution to this problem. Besides, it also offers the advantages of eliminating labour intensive process as well as the possible contamination involved in the periodic nutrient replenishments in the traditional T-flask stem cell cultivation. In spite of this, the optimization of HSC cultivation in a bioreactor has been barely explored. This manuscript discusses the development of a mathematical model to describe the dynamics in nutrient distribution and cell concentration of an ex vivo HSC cultivation in a microchannel perfusion bioreactor. The model was further used to optimize the cultivation by proposing three alternative feeding strategies in order to prevent the occurrence of nutrient limitation in the bioreactor. The evaluation of these strategies, the periodic step change increase in the inlet oxygen concentration, the periodic step change increase in the media inflow, and the feedback control of media inflow, shows that these strategies can successfully improve the cell yield of the bioreactor. In general, the developed model is useful for the design and optimization of bioreactor operation.
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Zeng YC, Wu R, Xu ZG, Zhang XY, Fan GL, Wu LN, Wang YM, Hao SH, Zheng W, Chen XD, Chi F, Zhang ZY, Li X, Jin XY, Chen W, Wang SL, Xiao FD, Wang EY, Dong XQ, Zhang LB, Jia MX, Xia HHX, Zhang HB, Li Y. Safety and radiation-enhancing effect of sodium glycididazole in locoregionally advanced laryngeal cancers previously treated with platinum-containing chemotherapy regimens: A preliminary report. Cancer Radiother 2010; 14:59-64. [PMID: 19695922 DOI: 10.1016/j.canrad.2009.06.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 06/05/2009] [Accepted: 06/19/2009] [Indexed: 02/07/2023]
Abstract
PURPOSE To determine the safety and radiation-enhancing effect of sodium glycididazole in laryngeal squamous cell carcinoma (stage T3-4,N0-3,M0) with conventional radiotherapy. PATIENTS AND METHODS Patients with locoregional advanced laryngeal cancer (stage T3-4,N0-3,M0) were included: group 1(control, n=30)were not administered of sodium glycididazole; group 2 (test, n=30) received sodium glycididazole at a dose of 700 mg/m(2) intravenous infusion 30 minutes before radiotherapy three times a week. Surrogate end-points of efficacy were tumor and nodal size. Safety parameters were vomiting, nausea, mucositis, laryngeal edema, esophagus and skin reaction, dysphagia, dyspnea, neurological deficit. Patients were evaluated weekly during treatment for 7 weeks and thereafter monthly for 3 months. RESULTS In the test, the overall response rate was 88.89% (95%CI, 71.00-97.00%) at 7 weeks and 92.59% (95%CI, 76.00 to 99.00%) at 1 month of follow-up. In the control, the overall response rate was 62.5% (95%CI, 41.00 to 81.00%) at 7 weeks and 58.33% (95%CI, 37.00 to 78.00%) at 1 month of follow-up. The short-term locoregional response rate was better in the test group at 7 weeks (p=0.027) and at 1 month (p=0.005) of follow-up. The test group had significantly more nausea and vomiting in weeks 1 (p=0.047), 2 (p=0.007), and 3 (p=0.01) of treatment. CONCLUSIONS The study indicates sodium glycididazole is an effective radiation-enhancing agent that improves short-term locoregional control and is well tolerated in patients with locoregionally advanced laryngeal cancer.
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Chen XD, Tang NS, Wang XR. On confidence regions of semiparametric nonlinear reproductive dispersion models. STATISTICS-ABINGDON 2009. [DOI: 10.1080/02331880802689332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Qi M, Lei T, Zhou L, Chen XD, Long H, Long QQ, Zhang RR, Yang ZQ, Gan L. Cloning, characterization, chromosomal mapping and tissue transcription analysis of porcine CREB2 and CREB3 genes. Folia Biol (Praha) 2009; 55:137-144. [PMID: 19691921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
CREB2 and CREB3 are two important members of the ATF/CREB family, which negatively and positively regulates CRE-dependent transcription in vitro. Here we report the cloning, chromosome mapping and tissue transcription analysis of CREB2 and CREB3 in pigs. The full-length coding sequence of CREB2 and CREB3 is 1047 bp and 1098 bp, encoding 348 and 365 amino acids, respectively. Porcine CREB3 comprises nine exons and eight introns, whereas CREB2 consists of three exons and two introns. CREB2 and CREB3 were cytogenetically assigned to porcine chromosome 5p and 1q28, respectively. Tissue transcription analysis revealed that both porcine CREB2 and CREB3 mRNA were ubiquitously detected in all examined tissues. Additionally, we cloned the 5' flank genomic sequence of porcine CREB3 and characterized several putative transcription factor recognition sites including SP1, NF-kappaB, AP-1 and AP-2 in its promoter region. Our studies provide basic molecular information helpful for further investigation of the function of the two genes in pig models.
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Yan TH, Wang W, Chen XD, Li Q, Xu C. Design of a smart ultrasonic transducer for interconnecting machine applications. SENSORS 2009; 9:4986-5000. [PMID: 22408564 PMCID: PMC3291949 DOI: 10.3390/s90604986] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2009] [Revised: 06/09/2009] [Accepted: 06/10/2009] [Indexed: 11/16/2022]
Abstract
A high-frequency ultrasonic transducer for copper or gold wire bonding has been designed, analyzed, prototyped and tested. Modeling techniques were used in the design phase and a practical design procedure was established and used. The transducer was decomposed into its elementary components. For each component, an initial design was obtained with simulations using a finite elements model (FEM). Simulated ultrasonic modules were built and characterized experimentally through the Laser Doppler Vibrometer (LDV) and electrical resonance spectra. Compared with experimental data, the FEM could be iteratively adjusted and updated. Having achieved a remarkably highly-predictive FEM of the whole transducer, the design parameters could be tuned for the desired applications, then the transducer is fixed on the wire bonder with a complete holder clamping was calculated by the FEM. The approach to mount ultrasonic transducers on wire bonding machines also is of major importance for wire bonding in modern electronic packaging. The presented method can lead to obtaining a nearly complete decoupling clamper design of the transducer to the wire bonder.
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Ding L, Chen TP, Liu Y, Ng CY, Yang M, Wong JI, Zhu FR, Tan MC, Fung S, Chen XD, Huang Y. Evolution of photoluminescence mechanisms of Si(+)-implanted SiO2 films with thermal annealing. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:3555-3560. [PMID: 19051910 DOI: 10.1166/jnn.2008.128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The information of band structure of silicon nanocrystal (nc-Si) embedded in SiO2 thin films synthesized by Si ion implantation and subsequent thermal annealing at various temperatures has been obtained from spectroscopy ellipsometric (SE) analysis. The indirect band structure and the energy gap of the nc-Si are not affected by the annealing. In contrast, the photoluminescence (PL) spectra show a continuous evolution with the annealing. Six PL bands located at 415, 460, 520, 630, 760, and 845 nm, respectively, have been observed depending on the annealing temperature. The annealing at 1100 degrees C yields the strongest PL band at 760 nm (approximately 1.63 eV) with the intensity much higher than that of all the other PL bands. Based on the knowledge of the band structure, the 760 nm-PL band could be attributed to the indirect band-to-band transition of the nc-Si assisted by the Si-O vibration of the nc-Si/SiO2 interface with the stretching frequency of approximately 1083 cm(-1) (approximately 0.13 eV). On the other hand, the first four PL bands mentioned above could originate from different extended defects in the oxide matrix, while the 845-nm PL band could be related to the interface luminescent centers.
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Ablikim M, Bai JZ, Bai Y, Ban Y, Cai X, Chen HF, Chen HS, Chen HX, Chen JC, Chen J, Chen XD, Chen YB, Chu YP, Dai YS, Deng ZY, Du SX, Fang J, Fu CD, Gao CS, Gao YN, Gu SD, Gu YT, Guo YN, Guo ZJ, Harris FA, He KL, He M, Heng YK, Hou J, Hu HM, Hu T, Huang GS, Huang XT, Huang YP, Ji XB, Jiang XS, Jiao JB, Jin DP, Jin S, Lai YF, Li HB, Li J, Li RY, Li WD, Li WG, Li XL, Li XN, Li XQ, Liang YF, Liao HB, Liu BJ, Liu CX, Liu F, Liu F, Liu HH, Liu HM, Liu JB, Liu JP, Liu HB, Liu J, Liu Q, Liu RG, Liu S, Liu ZA, Lu F, Lu GR, Lu JG, Luo CL, Ma FC, Ma HL, Ma LL, Ma QM, Malik MQA, Mao ZP, Mo XH, Nie J, Olsen SL, Ping RG, Qi ND, Qin H, Qiu JF, Rong G, Ruan XD, Shan LY, Shang L, Shen CP, Shen DL, Shen XY, Sheng HY, Sun HS, Sun SS, Sun YZ, Sun ZJ, Tang X, Tian JP, Tong GL, Varner GS, Wan X, Wang L, Wang LL, Wang LS, Wang P, Wang PL, Wang WF, Wang YF, Wang Z, Wang ZY, Wei CL, Wei DH, Weng Y, Wu N, Xia XM, Xie XX, Xu GF, Xu XP, Xu Y, Yan ML, Yang HX, Yang M, Yang YX, Ye MH, Ye YX, Yu CX, Yu GW, Yuan CZ, Yuan Y, Zang SL, Zeng Y, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HQ, Zhang HY, Zhang JW, Zhang JY, Zhang XY, Zhang YY, Zhang ZX, Zhang ZP, Zhao DX, Zhao JW, Zhao MG, Zhao PP, Zhao ZG, Zheng HQ, Zheng JP, Zheng ZP, Zhou BZL, Zhu KJ, Zhu QM, Zhu XW, Zhu YC, Zhu YS, Zhu ZA, Zhu ZL, Zhuang BA, Zou BS. Observation of Y(2175) in J/psi --> etaphif0 (980). PHYSICAL REVIEW LETTERS 2008; 100:102003. [PMID: 18352176 DOI: 10.1103/physrevlett.100.102003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Indexed: 05/26/2023]
Abstract
The decays of J/psi --> etaphif(0)(980)[eta --> gammagamma, phi --> K(+) K(-), f(0)(980) --> pi(+)pi(-)] are analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector at the Beijing Electron-Positron Collider. A structure at around 2.18 GeV/c(2) with about 5 sigma significance is observed in the phif(0)(980) invariant mass spectrum. A fit with a Breit-Wigner function gives the peak mass and width of m = 2.186+/-0.010(stat)+/-0.006(syst) GeV/c(2) and Gamma = 0.065+/-0.023(stat)+/-0.017(syst) GeV/c(2), respectively, which are consistent with those of Y(2175), observed by the BABAR Collaboration in the initial-state radiation process e(+)e(-) --> gamma(ISR) phif(0)(980). The production branching ratio is determined to be Br(J/psi --> etaY(2175))Br(Y(2175)- -> phif(0)(980))Br(f(0)(980) --> pi(+)pi(-)) = [3.23+/-0.75(stat)+/-0.73(syst)] x 10(-4), assuming that the Y(2175) is a 1(--) state.
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Jiang DK, Xu FH, Liu MY, Chen XD, Li MX, Liu YJ, Shen H, Deng HW. No evidence of association of the osteocalcin gene HindIII polymorphism with bone mineral density in Chinese women. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2007; 7:149-54. [PMID: 17627084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Osteoporosis is a major health problem, mainly characterized by low bone mineral density (BMD). Osteocalcin (also known as BGP, for bone Gla protein) is a significant biomarker of bone turnover and thus the BGP gene has been considered as an important candidate gene for osteoporosis. A few studies on the relationship between variants of the BGP gene and BMD variation, via traditional association and/or linkage methods, have yielded conflicting results. In the present study, we simultaneously tested linkage and/or association of the BGP HindIII polymorphism with BMD in a large cohort of pre-menopausal Chinese women. A total of 1,263 subjects from 402 Chinese nuclear families were examined. Each family consists of both parents and at least one daughter aged between 20-45 years. BMDs at the lumbar spine and hip were measured by dual-energy X-ray absorptiometry (DXA). Using the QTDT (quantitative transmission disequilibrium test) program, we did not detect significant evidence of linkage or association between the BGP HindIII polymorphisms and the BMD variation at any skeletal site. Our data do not support the BGP gene having a major effect on BMD variation in pre-menopausal Chinese women.
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Young MF, Bi Y, Ameye L, Xu T, Wadhwa S, Heegaard A, Kilts T, Chen XD. Small leucine-rich proteoglycans in the aging skeleton. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2006; 6:364-5. [PMID: 17185826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Small Leucine-Rich Proteoglyans (SLRPs) are major skeletal extracellular matrix (ECM) components that comprise a family of 13 members containing repeats of a leucine-rich motif. To examine SLRP function, we generated mice deficient in one or more member and analyzed them at the tissue, cell and molecular levels. This review outlines the novel research findings uncovered using these new animal models.
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73
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Feng SQ, Chen XD, Xia T, Gan L, Qiu H, Dai MH, Zhou L, Peng Y, Yang ZQ. Cloning, chromosome mapping and expression characteristics of porcine ANGPTL3 and -4. Cytogenet Genome Res 2006; 114:44-9. [PMID: 16717449 DOI: 10.1159/000091927] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2005] [Accepted: 10/20/2005] [Indexed: 11/19/2022] Open
Abstract
Angiopoietin-like protein 3 and -4 (ANGPTL3 and -4) are two members of angiopoietin-like proteins (ANGPTLs), which have the signature structure of the angiopoietin family but cannot bind to the TIE2 receptor. It has been reported that they both affect lipid metabolism by inhibiting the activity of lipoprotein lipase (LPL). Here we report the cDNA cloning, chromosome mapping and expression analysis of ANGPTL3 and -4 in pigs. Sequence analysis shows that ANGPTL3 contains an open reading frame of 1,389 bp, which encodes 462 amino acids, and ANGPTL4 contains a coding region of 1,239 bp, which encodes 412 amino acids. Porcine ANGPTL3 deduced amino acid sequence shares 83% and 73.7% identity with human and mouse, respectively, and ANGPTL4 shares 79.4% and 77.7% amino acid identity with human and mouse, respectively. Porcine ANGPTL3 and -4 were mapped to the 6q31-->q35 and 2q21-->q24 region, respectively, by radiation hybrid mapping. Tissue distribution analysis indicated that porcine ANGPTL3 mRNA was exclusively expressed in liver, and porcine ANGPTL4 was ubiquitously expressed with the highest abundance in white adipose tissue. Furthermore, the mRNA level of ANGPTL3 and -4 in liver and the mRNA level of ANGPTL4 in white adipose tissue were significantly higher in genetically obese pigs than in their lean counterparts. This is the first report of molecular cloning and characterization of ANGPTL3 and -4 in pigs, which will be helpful for a better understanding of the role of ANGPTLs in lipid metabolism.
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Nie T, Zhao XL, Qiu H, Xia T, Chen XD, Gan L, Feng SQ, Lei T, Dai MH, Yang ZQ. Sequence analysis and map assignment of pig SREBF2 and ADFP. Anim Genet 2006; 36:455-7. [PMID: 16167998 DOI: 10.1111/j.1365-2052.2005.01344.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Yang JH, Shi YF, Chen XD, Qi WJ. The influence of aquaporin-1 and microvessel density on ovarian carcinogenesis and ascites formation. Int J Gynecol Cancer 2006; 16 Suppl 1:400-5. [PMID: 16515633 DOI: 10.1111/j.1525-1438.2006.00476.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
This study aimed at investigating aquaporin-1 (AQP1) distribution and expression in primary ovarian epithelial tumors, correlating with clinicopathologic variables and intratumoral microvessel density (IMD). The AQP1 expression and IMD in 105 cases with primary epithelial ovarian tumors were measured by semiquantitative immunohistochemical technique. AQP1 was located mainly in microvessels and small vessels but seldom in tumor cells. Expression of AQP1 and IMD in ovarian malignant tumors was significantly higher than that in borderline tumors (P= 0.000, P= 0.001, respectively), and that in borderline tumors was higher than in benign tumors (P= 0.008, P= 0.028, respectively). The expression of AQP1 in FIGO stage III-IV was more than that in stage I-II (P= 0.001), and cases with ascites volume greater than 1000 mL were more than cases with ascites volume less than 1000 mL (P= 0.000). There is a positively correlated relationship between expression of AQP1 and IMD (correlation coefficient 0.60, P= 0.000) and between expression of AQP1 and ascites volume (correlation coefficient 0.57, P= 0.000). These data implicate that high AQP1 expression may play an important role in the ovarian carcinogenesis, progression, and ascites formation. Further studies into the mechanism of AQP1 regulation and the relationship between AQP1 expression and tumor angiogenesis may lead to novel therapies for ovarian carcinoma.
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