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Tang Q, Peng X, Cao H, Zheng X, Wang J. Spectroscopic Techniques Study on the Quenching Mechanism of Cytochrome B5 Affected by Cu(II). ACTA ACUST UNITED AC 2013. [DOI: 10.14233/ajchem.2013.13304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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102
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Li Y, Tang B, Guo F, Li J, Han W, Tang Q, Zhang Y. Effect of atorvastatin on left atrial function of patients with paroxysmal atrial fibrillation. GENETICS AND MOLECULAR RESEARCH 2013; 12:3488-94. [DOI: 10.4238/2013.september.10.5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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103
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Tang Q, Harrata AK, Lee CS. High-resolution capillary isoelectric focusing-electrospray ionization mass spectrometry for hemoglobin variants analysis. Anal Chem 2012; 68:2482-7. [PMID: 21619194 DOI: 10.1021/ac960169o] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
On-line capillary isoelectric focusing (CIEF)-electrospray ionization mass spectrometry (ESIMS) as a two-dimensional separation system is employed for high-resolution analysis of hemoglobin variants A, C, S, and F. The effects of moving ionic boundary inside the CIEF capillary and MS scan rate on the separation resolution and mass detection of hemoglobin variants are investigated. The formation of a moving ionic boundary due to the replacement of background electrolyte counterions with sheath liquid counterions can be minimized by combining cathodic mobilization with a gravity-induced hydrodynamic flow. Hemoglobin variants F and A, with a pI difference of 0.05 pH unit, are almost baseline resolved and identified in CIEF-ESIMS. The concentration detection limit for each hemoglobin variant is in the range of 10(-)(8) M, comparable to that obtained in two-dimensional gel electrophoresis using silver staining. Initial preconcentration during the focusing step and the use of single-ion monitoring scan mode are responsible for improving detection limits.
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Nijagal A, Fleck S, Hills NK, Feng S, Tang Q, Kang SM, Rosenthal P, MacKenzie TC. Decreased risk of graft failure with maternal liver transplantation in patients with biliary atresia. Am J Transplant 2012; 12:409-19. [PMID: 22221561 DOI: 10.1111/j.1600-6143.2011.03895.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The presence of maternal cells in offspring may promote tolerance to noninherited maternal antigens (NIMAs). Children with biliary atresia (BA) have increased maternal cells in their livers, which may impact tolerance. We hypothesized that patients with BA would have improved outcomes when receiving a maternal liver. We reviewed all pediatric liver transplants recorded in the SRTR database from 1996 to 2010 and compared BA and non-BA recipients of maternal livers with recipients of paternal livers for the incidences of graft failure and retransplantation. Rejection episodes after parental liver transplantation were examined for patients transplanted at our institution. BA patients receiving a maternal graft had lower rates of graft failure compared to those receiving a paternal graft (3.7% vs. 10.5%, p = 0.02) and, consequently, fewer episodes of retransplantation (2.7% vs. 7.5%, p = 0.04). These differences were not seen among non-BA patients or among BA patients who received female deceased donor grafts. In patients transplanted at our institution, paternal liver transplantation was associated with an increased incidence of refractory rejection compared to maternal liver transplantation only in BA. Our data support the concept that maternal cells in BA recipients promote tolerance to NIMAs and may be important in counseling BA patients who require liver transplantation.
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Xing L, Hu M, Tang Q, Wei J, Qin X, Zhou Z. Improved cyclic performances of LiCoPO4/C cathode materials for high-cell-potential lithium-ion batteries with thiophene as an electrolyte additive. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2011.10.054] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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106
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Wang T, Huang C, Jiang H, Tang Q, Li G. Characteristics of electrophysiology and effects of ouabian on transient outward potassium current and L-type calcium current of left atrium posterior wall of rabbits. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Driessen A, Tang Q, Hilderink L, Popma T. Production of Y‐Ba‐Cu‐0 Superconducting Thin Films by an Aerosol Chemical Vapor Deposition Process. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-169-601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractThin film production by aerosol deposition is a simple, non‐vacuum method, which under certain conditions of the process parameters, can be considered as a chemical vapor deposition (CVD) process. In this paper we describe the formation of superconducting thin films by aerosol deposition in the CVD regime by using metal‐organic precursors. The best results were obtained with the metal β‐diketonates of Y, Ba and Cu dissolved in butylacetate. This solution was nebulized and sprayed on a heated Si‐substrate with a Zr02‐buffer layer at a temperature of 450 C. After deposition a final heat treatment at a temperature of 800 C was applied. The resulting superconducting film has a Tc>2ero of 75 K.
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Gong X, Lu X, Wu X, Xu R, Tang Q, Xu G, Wang L, Zhang X, Zhao X. Role of bone marrow imprints in haematological diagnosis: a detailed study of 3781 cases. Cytopathology 2010; 23:86-95. [DOI: 10.1111/j.1365-2303.2010.00825.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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109
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Ma D, Zhang M, Chen L, Tang Q, Tang X, Mao Y, Zhou L. Hemangioblastomas might derive from neoplastic transformation of neural stem cells/progenitors in the specific niche. Carcinogenesis 2010; 32:102-9. [DOI: 10.1093/carcin/bgq214] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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110
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Tang Q, Li R, Clarkson R, Wu J, Yeung I. SU-GG-I-42: Measurement of Dynamic Contrast Enhancement in Rat Heart Using Gated Computed Tomography. Med Phys 2010. [DOI: 10.1118/1.3468075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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111
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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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Chang Y, Xue C, Tang Q, Li D, Wu X, Wang J. Isolation and characterization of a sea cucumber fucoidan-utilizing marine bacterium. Lett Appl Microbiol 2009; 50:301-7. [PMID: 20070508 DOI: 10.1111/j.1472-765x.2009.02792.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To isolate a fucoidan-utilizing strain from seawater for sea cucumber fucoidan degradation. METHODS AND RESULTS The utilization of sea cucumber fucoidan was monitored by H(2)SO(4)-phenol assay for neutral sugar. The bacterium CZ1127 was isolated from seawater and shown to have a relatively large maximum fucoidan-utilizing rate of 81.5%. CZ1127 was confirmed to belong to the family Flavobacteriaceae by 16S rDNA and physiological analyses. This strain has an ability to utilize fucoidans extracted from various sea cucumbers to different degrees. Both extracellular and intracellular enzymes of CZ1127 could degrade sea cucumber fucoidan, as confirmed by high-performance size exclusion chromatography. The M(r) of sea cucumber fucoidan could be reduced from 792.6 kDa to at least 3.7 kDa by the crude intracellular enzyme of this strain. CONCLUSIONS The marine bacterial strain CZ1127, which belongs to the family Flavobacteriaceae, was found to utilize various sea cucumber fucoidans and furthermore showed promise in sea cucumber fucoidan enzymatic degradation and oligosaccharide preparation. SIGNIFICANCE AND IMPACT OF THE STUDY The finding of a novel source can be applied in sea cucumber fucoidan enzymatic degradation. Furthermore, it is the first definite report of a bacterial strain that can utilize the fucoidans from various sea cucumbers.
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Song Y, Wang Z, Tang Q, Xu H, Xing C, Miao Z, Yang C. Partial cancerous changes eventually developing into superficial spreading cancer over 18 months. Curr Oncol 2009; 16:57-60. [PMID: 20016747 PMCID: PMC2794672 DOI: 10.3747/co.v16i6.424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this report, we describe a patient presenting with the superficial spreading type of early gastric cancer (egc) accompanied by cancerous ulcers. Disease progression and treatment outcome are discussed. After symptoms persisted for more than 1 year, the patient underwent total gastrectomy with D2 lymph node dissection. The patient was diagnosed with superficial spreading cancer (ssc), accompanied by an extensive iic lesions. The progression of this patient suggests that the co-occurrence of cancerous ulcers may contribute to egc development to some extent. As is known, egc often develops into advanced gastric cancer with time. However, in our case, we observed a process during which partial cancerous changes developed into ssc over 18 months. Superficial spreading cancer should be considered an egc variant, which may have the ability to spread superficially along the stomach wall without invading the muscularis propria. But we speculate that, if gene expression changes for some reason, the malignant ssc cells may acquire the ability to grow deeply into the stomach wall. Eventually, Borrmann type iv gastric cancer may develop.
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Feng F, Liu L, Shen Z, Xia W, Zhou W, Wang M, Zhu Y, Wang J, Tang Q. UP-2.174: Clinical Experience in a Modified Roux-Y Shaped Sigmoid Neobladder: Assessment of Complications, Voiding Patterns in 43 Patients. Urology 2009. [DOI: 10.1016/j.urology.2009.07.393] [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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Kalmatsky B, Bhagan S, Tang Q, Bargiello TA, Dowd T. Structural studies of the N-terminus of Connexin 32 using 1H NMR spectroscopy. Arch Biochem Biophys 2009; 490:9-16. [PMID: 19638273 PMCID: PMC4510928 DOI: 10.1016/j.abb.2009.07.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2009] [Revised: 07/03/2009] [Accepted: 07/22/2009] [Indexed: 10/20/2022]
Abstract
The amino terminus of gap junction proteins, connexins, plays a fundamental role in voltage gating and ion permeation. We have previously shown with (1)H NMR that the structure of the N-terminus of a representative connexin molecule contains a flexible turn around glycine 12 [P.E. Purnick, D.C. Benjamin, V.K. Verselis, T.A. Bargiello, T.L. Dowd, Arch. Biochem. Biophys. 381 (2000) 181-190] allowing the N-terminus to reside at the cytoplasmic entry of the channel forming a voltage-sensor. Previous functional studies or neuropathies have shown that the mutation G12Y and G12S form non-functional channels while functional channels are formed from G12P. Using 2D (1)H NMR we show that similar to G12, the structure of the G12P mutant contains a more flexible turn around residue 12, whereas the G12S and G12Y mutants contain tighter, helical turns in this region. These results suggest an unconstrained turn is required around residue 12 to position the N-terminus within the pore allowing the formation of the cytoplasmic channel vestibule, which appears to be critical for proper channel function.
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Dou J, Li Y, Zhao F, Hu W, Wen P, Tang Q, Chu L, Wang Y, Cao M, Jiang C, Gu N. Identification of tumor stem-like cells in a mouse myeloma cell line. Cell Mol Biol (Noisy-le-grand) 2009; 55 Suppl:OL1151-OL1160. [PMID: 19656468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2008] [Accepted: 06/15/2009] [Indexed: 05/28/2023]
Abstract
We used colony formation assay in the soft agar media or the serum-free media, the methods of identifying BrdU-label-retaining cells and the SP cells as well as the tumorigenicity test in BALB/c mice, respectively, to analyze tumor stem like cells in the SP2/0 cell line. The results showed that a few SP2/0 cells were capable of forming colonies in the soft agar media, contained BrdU-label-immortal strand in the SP2/0 cell line. The SP2/0 cells in the serum-free media gained higher tumorigenicity in the BALB/c mice than the SP2/0 cells cultivated in the complete media did. Overall, only a few of the SP2/0 cells were found to possess the characteristics of tumor stem-like cells, such as high proliferative potency, more self-renewal and stronger tumorigenesis, or greater similarity to the tumor stem cells (TSCs) traits. The biology of tumor stem-like cells contributes to the identification of molecular targets important for future tumor therapy.
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Chen C, Tang Q, Huang X, Wu Z, Hua H, Yu Y, Chen S. An Assessment of the Completeness of Scholarly Information on the Internet. COLLEGE & RESEARCH LIBRARIES 2009. [DOI: 10.5860/crl.70.4.386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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118
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Yeung I, Dawson L, Cho Y, Moseley D, Case R, Tang Q. SU-FF-I-43: Iterative Methods of Cone-Beam CT Image Reconstruction for Under-Sampled and Truncated Projection Data. Med Phys 2009. [DOI: 10.1118/1.3181162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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119
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Brennan T, Jaigirdar A, Hoang V, Hayden T, Liu FC, Zaid H, Chang C, Bucy R, Tang Q, Kang SM. Preferential priming of alloreactive T cells with indirect reactivity. Am J Transplant 2009; 9:709-18. [PMID: 19344462 PMCID: PMC5990255 DOI: 10.1111/j.1600-6143.2009.02578.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The relative contributions of the direct and indirect pathways in alloimmune responses have not been fully elucidated. We report a novel murine TCR transgenic system that can simultaneously track the CD4-direct (CD4-d), CD4-indirect (CD4-i) and CD8-direct (CD8-d) pathways after transplantation. Using this system, we have observed a profoundly greater proliferation of CD4-i T cells relative to CD4-d and CD8-d T cells after transplantation. Furthermore, a much larger proportion of CD4-i T cells attain an effector phenotype. We also analyzed endogenous, wild-type T cells using enzyme-linked immunospot analysis. In naïve mice, T cells with indirect reactivity were undetectable, but T cells with direct reactivity were abundant. However, 10 days after skin or heterotopic heart transplantation, CD4-i T cells comprised approximately 10% of the CD4+ response. Consistent with increased priming of the CD4-i pathway, we observed that the CD4-i T cells were further enriched in the effector cells migrating to the allograft and in memory-like T cells persisting after rejection. Thus, priming of the CD4-i pathway is favored after transplantation, allowing a rare population to rapidly become a major component of the CD4+ T-cell response in acute allograft rejection. The generalizability of this observation to other models remains to be determined.
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Gao F, Tang Q, Yang P, Fang Y, Li W, Wu Y. Apoptosis inducing and differentiation enhancement effect of oridonin on the all-trans-retinoic acid-sensitive and -resistant acute promyelocytic leukemia cells. Int J Lab Hematol 2009; 32:e114-22. [PMID: 19302235 DOI: 10.1111/j.1751-553x.2009.01147.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We investigated the effects of oridonin (Ori), a diterpenoid isolated from Rabdosia rubescens, on apoptosis and differentiation of all-trans-retinoic acid (ATRA)-sensitive (NB4) and ATRA-resistant (NB4-R1) cells. The results showed that reactive oxygen species initiates Ori-induced apoptosis. In addition, we found that neither Ori nor ATRA (10 nM) alone induced marked cell differentiation, while co-treatment of these two compounds can induce differentiation of NB4 and NB4-R1 cells which was accompanied by increased RARalpha, C/EBPepsilon or C/EBPbeta. This is the first report to show that RARalpha could be accumulated by Ori which may be useful as a probe to investigate the mechanism of RARalpha catabolism. These results suggest that Ori is a potential candidate for acute promyelocytic leukemia cancer therapy.
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Han Y, Tang Q, Zhu W, Zhang X, You L. OL-010 Biochemical, immunological and virological profiles of, and differential diagnosis between patients with acute hepatitis B and chronic hepatitis B with acute flare. Int J Infect Dis 2008. [DOI: 10.1016/s1201-9712(09)60107-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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122
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Tang Q, Kim S, Clarkson R, Cho YB, Moseley D, Yeung I. Sci-Sat AM(1): Imaging-03: On-line dynamic contrast enhanced cone-beam CT for measuring. Med Phys 2008; 35:3414-3415. [DOI: 10.1118/1.2965987] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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123
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Tang Q, Kim S, Clarkson R, Moseley D, Cho Y, Yeung I. WE-C-351-02: On-Line Perfusion Measurement with Dynamic Contrast Enhanced Cone-Bean CT in Radiation Therapy. Med Phys 2008. [DOI: 10.1118/1.2962709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Tang Q, Li ZQ, Li W, Guo J, Sun HY, Zhang XH, Lau CP, Tse HF, Zhang S, Li GR. The 5-HT2 antagonist ketanserin is an open channel blocker of human cardiac ether-à-go-go-related gene (hERG) potassium channels. Br J Pharmacol 2008; 155:365-73. [PMID: 18574455 DOI: 10.1038/bjp.2008.261] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Ketanserin, a selective 5-HT receptor antagonist, prolongs the QT interval of ECG in patients. The purpose of the present study was to determine whether ketanserin would block human cardiac ether-à-go-go-related gene (hERG) potassium channels. EXPERIMENTAL APPROACH Whole-cell patch voltage-clamp technique was used to record membrane currents in HEK 293 cells expressing wild type or mutant hERG channel genes. KEY RESULTS Ketanserin blocked hERG current (I(hERG)) in a concentration-dependent manner (IC50=0.11 microM). The drug showed an open channel blocking property, the block increasing significantly at depolarizing voltages between +10 to +60 mV. Voltage-dependence for inactivation of hERG channels was negatively shifted by 0.3 microM ketanserin. A 2.8 fold attenuation of inhibition by elevation of external K+ concentration (from 5.0 to 20 mM) was observed, whereas the inactivation-deficient mutants S620T and S631A had the IC50s of 0.84 +/- 0.2 and 1.7 +/-0.4 microM (7.6 and 15.4 fold attenuation of block). In addition, the hERG mutants in pore helix and S6 also significantly reduced the channel block (2-59 fold) by ketanserin. CONCLUSIONS AND IMPLICATIONS These results suggest that ketanserin binds to and blocks the open hERG channels in the pore helix and the S6 domain; channel inactivation is also involved in the blockade of hERG channels. Blockade of hERG channels most likely contributes to the prolongation of QT intervals in ECG observed clinically at therapeutic concentrations of ketanserin.
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Huang J, Cai W, Tang Q, Feng Y, Tao Y, Wang Y, Wu J. Long-term cognitive functions in neonatal short bowel syndrome patients. Eur J Pediatr Surg 2008; 18:89-92. [PMID: 18437651 DOI: 10.1055/s-2007-965746] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE The aim of the study was to evaluate the long-term effects of neonatal short bowel syndrome on cognitive functions during development. SUBJECTS AND METHODS Nine patients diagnosed with short bowel syndrome during the neonatal period were enrolled in this study. Their medical records were reviewed; anthropometric measurements and blood tests were assayed; IQ tests (the Chinese versions of WAIS-R, WPPSI-R and WISC-R) were performed depending on their age, and a BSID assessment was carried out in those patients less than 4 years old. RESULTS Eight of 9 patients were followed up except for one patient who died in a car accident at the age of three. All patients had been weaned off parenteral nutrition for more than 2 years. The average residual small bowel length was 58.1 cm (range 35-70 cm), and the mean parenteral nutrition (PN) duration was 73.1 days (43-147 days). The mean duration of the period without PN was 7.4 years (range 2.1-17.1 years). Weight, height and BMI for age were normal in 7 children except for 1 child, who was overweight. Hemoglobin and albumin concentrations were normal in all 8 patients. Evaluation of cognitive development showed normal results for all 8 patients while a verbal/performance discrepancy was found in 2. CONCLUSION Patients with neonatal SBS who were weaned off PN for more than 2 years were found to have normal growth and cognitive development during this long-term follow-up. There was no evidence for a strong correlation between SBS and nutritional/cognition disorder. Longer term and controlled studies with a larger sample size are warranted.
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Kay DA, Sagheer M, Tang Q. Mathematical analysis of an integral equation arising from population dynamics. Math Biosci 2007; 210:415-35. [PMID: 17707863 DOI: 10.1016/j.mbs.2007.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 05/17/2007] [Accepted: 05/18/2007] [Indexed: 11/21/2022]
Abstract
In this paper, we establish the existence of travelling wave solution to an intrinsically non-linear differential-integral equation formed as a result of mathematical modelling of the evolution of an asexual population in a changing environment. This equation is first converted to a non-linear integral equation. The discretization and manipulation of the corresponding eigenvalue problem allows us to use the theory of positive matrices to get some very useful estimates and then to confirm the existence of solution. We also exhibit numerical simulation results and explain the biological meaning of the results.
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Kong Q, Sun T, Dou Q, Li F, Tang Q, Pei F, Tu C, Chen Z. β-CTX and ICTP Act as Indicators of Skeletal Metastasis Status in Male Patients with Non-Small Cell Lung Cancer. Int J Biol Markers 2007; 22:214-20. [DOI: 10.1177/172460080702200309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Bone metastasis is common in lung cancer patients and associated with reduced quality of life and reduced overall and median survival, so the early detection of bone metastasis and monitoring of its status is very important for clinicians. Serum bone-specific alkaline phosphatase (BAP), osteocalcin (OC), β isomer of C-terminal telopeptide of type I collagen (β-CTX) and cross-linked C-terminal telopeptide of type I collagen (ICTP) were compared with regard to their usefulness as indicators of bone metastasis in lung cancer. The serum concentrations of the 4 markers were measured by commercially available tests in 96 male patients with non-small cell lung cancer and 30 male patients with other pulmonary diseases. The levels of both β-CTX and ICTP were significantly higher in 61 lung cancer patients with bone metastases than in 35 lung cancer patients without bone metastases (both p<0.001), and significantly correlated with the extent of bone disease. Although ICTP had a better sensitivity and accuracy than β-CTX (75.4% vs 65.6% and 72.9% vs 68.8%, respectively), they had a similar area under the receiver operating characteristic curve (0.85 vs 0.83). These results support the use of β-CTX and ICTP as an adjunct tool for the diagnosis and screening of bone metastasis in lung cancer.
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Kang SM, Tang Q, Bluestone JA. CD4+CD25+ regulatory T cells in transplantation: progress, challenges and prospects. Am J Transplant 2007; 7:1457-63. [PMID: 17511675 DOI: 10.1111/j.1600-6143.2007.01829.x] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The involvement of CD4(+)CD25(+) regulatory T cells (Treg) in general immune homeostasis and protection from autoimmune syndromes is now well established. Similarly, there has been increasing evidence for Treg involvement in allograft rejection and current immunotherapies. However, despite significant advances in understanding the development, function, and therapeutic efficacy of Treg in certain well-defined rodent models, the relevance of Treg to clinical transplantation remains unclear. In this review, we summarize our current understanding of the role of Treg in immunity and organ transplantation in experimental and clinical settings. In addition, we review advances in using Treg as a form of immune therapy. The goal is to highlight the complexities and opportunities in the field and to provide evidence to support the use of antigen-specific Tregs in the context of transplantation to facilitate a robust and selective state of immune tolerance.
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van Loon J, Smid H, Wang H, Chyb S, Tang Q, Wang C. From simple to complex stimuli in insect taste: The need for improvement of analysis and interpretation of multi-neural electrophysiological recordings. Comp Biochem Physiol A Mol Integr Physiol 2007. [DOI: 10.1016/j.cbpa.2007.01.154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Yao S, Tang Q, Cheng L, Zeng Y, Chen X, Qin D, Lv Z, Lu C. Identification of B cell epitopes at the C-terminus of latency-associated nuclear protein of the kaposi's sarcoma-associated herpesvirus. Acta Virol 2007; 51:109-18. [PMID: 17900217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) plays a key role in the induction of cell transformation, maintenance of viral episome, and modulation of immune response in human. To identify the presence of B cell epitopes within C-terminus of LANA and to characterize the monoclonal antibodies (MAbs) against this protein, we expressed the C-terminal region at aa 794-1000 of LANA (pLANA-C) in Escherichia coli as a fusion protein. KSHV-positive human sera were able to recognize the recombinant LANA-C in the Western blot analysis and ELISA. Mapping of antigenic epitopes of pLANA-C by KSHV-positive human sera revealed two B cell antigenic epitopes located at aa 846-854 and aa 794-822. The MAb 3F11 recognized a region between at aa 840 to 846 of LANA and exhibited a strong and specific binding to both pLANA-C and native viral LANA. These findings showed that pLANA-C and MAb 3F11 could be used for the detection of KSHV antibodies in human sera and for the advanced study of biological functions of LANA.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Viral/blood
- Antibodies, Viral/immunology
- Antigens, Viral/chemistry
- Antigens, Viral/genetics
- Antigens, Viral/immunology
- Cell Line
- Epitopes, B-Lymphocyte/chemistry
- Epitopes, B-Lymphocyte/immunology
- Herpesviridae Infections/diagnosis
- Herpesviridae Infections/immunology
- Herpesviridae Infections/virology
- Herpesvirus 8, Human/immunology
- Humans
- Mice
- Nuclear Proteins/chemistry
- Nuclear Proteins/genetics
- Nuclear Proteins/immunology
- Recombinant Proteins/genetics
- Recombinant Proteins/immunology
- Recombinant Proteins/metabolism
- Sarcoma, Kaposi/diagnosis
- Sarcoma, Kaposi/immunology
- Sarcoma, Kaposi/virology
- Virus Latency
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Feng L, Cheng F, Ye Z, Li S, He Y, Yao X, Tang Q, Li Y. The effect of renal ischemia-reperfusion injury on expression of RAE-1 and H60 in mice kidney. Transplant Proc 2006; 38:2195-8. [PMID: 16980040 DOI: 10.1016/j.transproceed.2006.06.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
INTRODUCTION NKG2D, an activating receptor, may trigger NK and CD8+ T cells. Ligands for NKG2D and major histocompability complex class I chain-related antigen (MIC) have been reported to be expressed in rejected human renal allografts. MIC-NKG2D engagement may induce natural killer (NK) cell activation providing T-cell costimulation. We hypothesized that this interaction between innate and adaptive immunity may occur during kidney ischemia-reperfusion injury (IRI). METHODS Male C57BL/6 mice after right renal resection were subjected to 35 minutes of left renal ischemia: the ischemic group. Sham-operated mice underwent the same protocol without vascular occlusion. The sham and ischemic kidneys were removed at 2 to 7, 10, 14, or 28 days postoperatively. The normal, sham, and ischemic kidney tissues were collected for reverse-transcriptase polymerase chain reaction, and immunohistochemistry analysis of MIC homologues in mice (Rae-1 and H60). RESULTS Compared with no expression in sham control and normal kidneys, IRI caused mRNA expression of Rae-1 from 2 to 10 days postoperatively and protein expression of Rae-1 from 2 to 14 days postoperatively in ischemic kidneys. We observed no expression of H60 mRNA or protein in any kidney. CONCLUSION H60 transcripts have been reported to be present in the BALB/c background but not in C57BL/6. We found IRI did not cause H60 mRNA on protein expression in C57BL/6 kidneys. Rae-1 was absent in normal C57BL/6 kidneys. The IRI-induced expression of the NKG2D ligand, Rae-1, might activate NK and CD8+ T cells. Our results suggested that MIC may be an important link between innate and adaptive immunity in kidney IRI.
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Wang L, Fu SH, Li X, Niu XL, Tang Q, Liang GD. [Preparation and characterization of the monoclonal antibodies against Japanese encephalitis virus.]. ZHONGHUA SHI YAN HE LIN CHUANG BING DU XUE ZA ZHI = ZHONGHUA SHIYAN HE LINCHUANG BINGDUXUE ZAZHI = CHINESE JOURNAL OF EXPERIMENTAL AND CLINICAL VIROLOGY 2006; 20:209-12. [PMID: 17086272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
BACKGROUND To prepare mouse monoclonal antibodies (McAbs) against Japanese encephalitis virus (JEV)and evaluate their biological characteristics. METHODS McAbs against JEV were prepared by immunizing, fusing, cloning and screening. Their sensitivity, specificity, universality and neutralizing function were analyzed with ELISA, IFA, NT and Western blot. RESULTS Titers of three McAbs against JEV were higher than 106. Three McAbs only reacted with JEV and not with other nine arboviruses. F12.37 could react with ten strains of JEV and sensitively detected ten replicating strains of viruses in BHK cell. The strains P3 and SH03-103 of JEV were neutralized by F12.37, its titers of protecting 50% cell were 3.2x105 and 105. Western blot showed that F12.37 reacted with envelop(E)protein of JEV. CONCLUSION Three McAbs against JEV had high titer and good specificity. And F12.37 was very sensitive and universal in reacting with JEV, and neutralized JEV of Genotype I and Genotype .The binding site of F12.37 lays in E protein of JEV.
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Abstract
OBJECTIVES To evaluate resting energy expenditure (REE) in surgical infants and define the effects of the degree of stress on its level. SUBJECTS AND METHODS Between June 1999 and June 2003 forty-five infants awaiting surgery (boys/girls: 32/13) from the Department of Pediatric Surgery were entered in the study. Indirect calorimetry was used to measure the REE of all the patients before operation and 1 - 7 days after operation. Clinical data were collected, including age, weight, height, diagnosis, operative method, site and duration, and first day postoperative C-reactive protein (CRP) levels. RESULTS The REE before operation did not differ significantly from the postoperative values (paired t-test, p > 0.05). The predicted REE was significantly higher than the measured REE even before and after the operation (p < 0.01). REE values in the first three postoperative days were lower in the mild stress group than in the severe surgical stress group. CONCLUSIONS REE variation among the patients is relatively large. Changes in REE may be related to the degree of stress. Predicted REE values may be not a good reflection of measured REE.
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Huang WX, Desai M, Tang Q, Yang R, Vivilecchia RV, Joshi Y. Elimination of metformin-croscarmellose sodium interaction by competition. Int J Pharm 2006; 311:33-9. [PMID: 16426778 DOI: 10.1016/j.ijpharm.2005.12.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2005] [Revised: 12/05/2005] [Accepted: 12/05/2005] [Indexed: 11/24/2022]
Abstract
During analytical method development and validation, a strong charge interaction between metformin and croscarmellose sodium was observed when the aqueous solution containing metformin was spiked with croscarmellose sodium. The charge interaction resulted in the retention of metformin in croscarmellose sodium and caused a serious drug recovery problem. The percent recovery of metformin in the solution was much lower than its theoretical values, especially in the low metformin concentration range. To overcome the metformin-croscarmellose interaction, arginine was selected as a competitor for the binding sites on croscarmellose sodium. Because of the competition and stronger interaction between arginine and croscarmellose sodium than metformin and croscarmellose sodium, a complete recovery of metformin in presence of arginine in both low and high concentration ranges was achieved. The effect of arginine on the recovery of metformin and the competition mechanism are discussed in this paper.
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Luo DL, Tang Q, Zhang CX. Defect complexes in Re3+-doped magnesium sulphate phosphors. RADIATION PROTECTION DOSIMETRY 2006; 119:57-61. [PMID: 16644940 DOI: 10.1093/rpd/nci680] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A series of magnesium sulphate phosphors MgSO4:RE3+,X ( RE = Dy, Tm, Eu and X = P, Mn) have been prepared and studied. Based on the experimental results of thermoluminescence (TL) emission spectra and dose responses studies, it is proposed that in these phosphors large defect complexes are formed, which include intrinsic imperfections and dopants. These defect complexes were formed in the course of preparation of phosphors and could be regarded as basic elements in the TL multi-stage processes. This defect model might be applicable to the most of TL materials.
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Tang Q, Zhang CX, Luo DL, Leung PL, Xiong ZY. TL and OSL of SrSO4 phosphors doped with Eu. RADIATION PROTECTION DOSIMETRY 2006; 119:238-43. [PMID: 16644983 DOI: 10.1093/rpd/nci578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The thermoluminescence (TL) and optically stimulated luminescence (OSL) of SrSO4:Eu (0.1 mol%) powder sample were studied. The TL and OSL emission spectrum are measured after irradiation (absorbed dose 100 Gy) of 90Sr source; both of them showed that the emission wavelength is at approximately 375 nm, which indicates that TL and OSL have the same luminescence centres, and the luminescence comes from transitions between the energy levels of Eu2+. The TL glow curves and OSL decay curves illustrate that there is only one main TL peak but two main components in OSL curves. By a comparative study of TL and OSL it is concluded that OSL traps are different from TL traps. The TL and OSL dose responses of SrSO4:Eu phosphor were measured, and it showed that phosphor has similar dose responses for OSL and TL.
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138
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Zhang CX, Tang Q, Lin LB, Luo DL. Thermoluminescence glow curves and optical stimulated luminescence of undoped alpha-Al2O3 crystals. RADIATION PROTECTION DOSIMETRY 2006; 119:402-7. [PMID: 16644982 DOI: 10.1093/rpd/nci579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The characteristics of thermoluminescence (TL) and optical stimulated luminescence (OSL) in undoped alpha-Al2O3 single crystals were studied. The TL glow curves of the crystal samples irradiated at various dose levels were measured by RisØ TL/OSL-DA-15B/C reader with U-340 or 7-59 filters at different heating rates. The glow peaks measured with U-340 at approximately 210 degrees C of the undoped alpha-Al2O3 can be well fitted by first-order kinetic equation whereas the glow peaks measured with 7-59 filters are a composite of two first-order glow peaks. It indicates that the TL glow curves are dependent upon the filter used in the reader that is related to the emission spectra of luminescence materials. The OSL were also measured and fitted by two exponential functions to get the luminescence intensities. The TL and OSL dose responses of the undoped alpha-Al2O3 crystal were obtained in the dose range of 0.12-248 Gy and fitted by the composite action dose-response function to get nonlinear characteristic parameters. The TL and OSL dose responses are linear-sublinear.
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139
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Earle KE, Tang Q, Zhou X, Liu W, Zhu S, Bonyhadi ML, Bluestone JA. In vitro expanded human CD4+CD25+ regulatory T cells suppress effector T cell proliferation. Clin Immunol 2005; 115:3-9. [PMID: 15870014 PMCID: PMC7128890 DOI: 10.1016/j.clim.2005.02.017] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2005] [Indexed: 11/27/2022]
Abstract
Regulatory T cells (Tregs) have been shown to be critical in the balance between autoimmunity and tolerance and have been implicated in several human autoimmune diseases. However, the small number of Tregs in peripheral blood limits their therapeutic potential. Therefore, we developed a protocol that would allow for the expansion of Tregs while retaining their suppressive activity. We isolated CD4+CD25 hi cells from human peripheral blood and expanded them in vitro in the presence of anti-CD3 and anti-CD28 magnetic Xcyte Dynabeads and high concentrations of exogenous Interleukin (IL)-2. Tregs were effectively expanded up to 200-fold while maintaining surface expression of CD25 and other markers of Tregs: CD62L, HLA-DR, CCR6, and FOXP3. The expanded Tregs suppressed proliferation and cytokine secretion of responder PBMCs in co-cultures stimulated with anti-CD3 or alloantigen. Treg expansion is a critical first step before consideration of Tregs as a therapeutic intervention in patients with autoimmune or graft-versus-host disease.
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Song S, Goudy K, Campbell-Thompson M, Wasserfall C, Scott-Jorgensen M, Wang J, Tang Q, Crawford JM, Ellis TM, Atkinson MA, Flotte TR. Recombinant adeno-associated virus-mediated alpha-1 antitrypsin gene therapy prevents type I diabetes in NOD mice. Gene Ther 2004; 11:181-6. [PMID: 14712302 DOI: 10.1038/sj.gt.3302156] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Type I diabetes results from an autoimmune destruction of the insulin-producing pancreatic beta cells. Although the exact immunologic processes underlying this disease are unclear, increasing evidence suggests that immunosuppressive, immunoregulatory and anti-inflammatory agents can interrupt the progression of the disease. Alpha 1 antitrypsin (AAT) is a multifunctional serine proteinase inhibitor (serpin) that also displays a wide range of anti-inflammatory properties. To test the ability of AAT to modulate the development of type I diabetes, we performed a series of investigations involving recombinant adeno-associated virus vector (rAAV)-mediated gene delivery of human alpha-1 antitrypsin (hAAT) to nonobese diabetic (NOD) mice. Recombinant AAV-expressing hAAT (rAAV2-CB-AT) was administered intramuscularly to 4-week-old female NOD mice (1 x 10(10) i.u./mouse). A single injection of this vector reduced the intensity of insulitis, the levels of insulin autoantibodies, and the frequency of overt type I diabetes (30% (3/10) at 32 weeks of age versus 70% (7/10) in controls). Transgene expression at the injection sites was confirmed by immunostaining. Interestingly, antibodies against hAAT were present in a majority of the vector-injected mice and circulating hAAT was undetectable when assessed 10 weeks postinjection. This study suggests a potential therapeutic role for AAT in preventing type I diabetes as well as the ability of AAV gene therapy-based approaches to ameliorate disease effectively.
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141
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Broom M, Tang Q, Waxman D. Mathematical analysis of a model describing evolution of an asexual population in a changing environment. Math Biosci 2003; 186:93-108. [PMID: 14527749 DOI: 10.1016/s0025-5564(03)00097-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigate a mathematical model for an asexual population with non-overlapping (discrete) generations, that exists in a changing environment. Sexual populations are also briefly discussed at the end of the paper. It is assumed that selection occurs on the value of a single polygenic trait, which is controlled by a finite number of loci with discrete-effect alleles. The environmental change results in a moving fitness optimum, causing the trait to be subject to a combination of stabilising and directional selection. This model is different from that investigated by Waxman and Peck [Genetics 153 (1999) 1041] where overlapping generations and continuous effect alleles were considered. In this paper, we consider non-overlapping generations and discrete effect alleles. However in [Genetics 153 (1999) 1041] and the present work, there is the same pattern of environmental change, namely a constant rate of change of the optimum. From [Genetics 153 (1999) 1041], no rigorous theoretical conclusion can be drawn about the form of the solutions as t grows large. Numerical work carried out in [Genetics 153 (1999) 1041] suggests that the solution is a lagged travelling wave solution, but no mathematical proof exists for the continuous model. Only partial results, regarding existence of travelling wave solutions and perturbed solutions, have been established (see [Nonlin. Anal. 53 (2003) 683; An integral equation describing an asexual population in a changing environment, Preprint]). For the discrete case of this paper, under the assumption that the ratio between the unit of genotypic value and the speed of environment change is a rational number, we are able to give rigorous proof of the following conclusion: the population follows the environmental change with a small lag behind, moreover, the lag is represented using a calculable quantity.
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Loiler SA, Conlon TJ, Song S, Tang Q, Warrington KH, Agarwal A, Kapturczak M, Li C, Ricordi C, Atkinson MA, Muzyczka N, Flotte TR. Targeting recombinant adeno-associated virus vectors to enhance gene transfer to pancreatic islets and liver. Gene Ther 2003; 10:1551-8. [PMID: 12907946 DOI: 10.1038/sj.gt.3302046] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Human pancreatic islet cells and hepatocytes represent the two most likely target cells for genetic therapy of type I diabetes. However, limits to the efficiency of rAAV serotype 2 (rAAV2)-mediated gene transfer have been reported for both of these cell targets. Here we report that nonserotype 2 AAV capsids can mediate more efficient transduction of islet cells, with AAV1 being the most efficient serotype in murine islets, suggesting that receptor abundance could be limiting. In order to test this, we generated rAAV particles that display a ligand (ApoE) that targets the low-density lipoprotein receptor, which is present on both of these cell types. The rAAV/ApoE viruses greatly enhanced the efficiency of transduction of both islet cells ex vivo and murine hepatocytes in vivo when compared to native rAAV2 serotype (220- and four-fold, respectively). The use of receptor-targeted rAAV particles may circumvent the lower abundance of receptors on certain nonpermissive cell types.
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143
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Wicks BJ, Joensen R, Tang Q, Randall DJ. Swimming and ammonia toxicity in salmonids: the effect of sub lethal ammonia exposure on the swimming performance of coho salmon and the acute toxicity of ammonia in swimming and resting rainbow trout. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2002; 59:55-69. [PMID: 12088633 DOI: 10.1016/s0166-445x(01)00236-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study tested the hypothesis that swimming exacerbates ammonia toxicity in fish. Both sub-lethal and acute toxicity testing was conducted in a swim tunnel on swimming and resting coho salmon and rainbow trout, respectively. The sub lethal tests on coho salmon also considered the compartmentalization of ammonia within the fish. Coho salmon showed a significant linear decrease in U(crit) both with increasing water ammonia (0, 0.02, 0.04 and 0.08 mg per l NH3) and increasing plasma ammonia. Data collected included plasma pH and ammonia, muscle pH and ammonia and muscle membrane potential. Based on results found in these experiments it was concluded that the reduction in swimming performance was due to both metabolic challenges as well as depolarization of white muscle. Acute toxicity testing on swimming and resting rainbow trout revealed that swimming at (60% U(crit) or approximately 2.2 body lengths/s) decreased the LC50 level from 207+/-21.99 mg N per l in resting fish to 32.38+/-10.81. The LC50 for resting fish was significantly higher than that for swimming fish. The acute value set forth by the US EPA at the same pH is 36.1 mg N per l and may not protect swimming fish. In addition the effect of water hardness on ammonia toxicity was considered. It was found that increased water calcium ameliorates ammonia toxicity in fish living in high pH water.
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Willocquet L, Savary S, Fernandez L, Elazegui F, Castilla N, Zhu D, Tang Q, Huang S, Lin X, Singh H, Srivastava R. Structure and validation of RICEPEST, a production situation-driven, crop growth model simulating rice yield response to multiple pest injuries for tropical Asia. Ecol Modell 2002. [DOI: 10.1016/s0304-3800(02)00014-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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145
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Zhang CX, Tang Q, Luo DL, Qiu ZR, Leung PL, Stokes MJ. Thermoluminescence of MgSO4 doped with Eu and P impurities. RADIATION PROTECTION DOSIMETRY 2002; 100:407-411. [PMID: 12382909 DOI: 10.1093/oxfordjournals.rpd.a005901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
CaSO4:Eu, MgSO4:Eu and MgSO4:Eu,P phosphors have been prepared and their thermoluminescence (TL) characteristics were studied. A main glow peak due to Eu2+ ions is seen at approximately 146 degrees C and 440 nm and glow peaks at approximately 145 degrees C, approximately 190 degrees C, approximately 260 degrees C and approximately 360 degrees C for 590 nm and 625 nm wavelengths are identified as Eu3+ ion emissions in MgSO4:Eu. Emission spectra in MgSO4:Eu and the MgSO4:Eu,P show that the MgSO4:Eu3+ glow peak at 260 degrees C for 590 nm and 625 nm shifts to 280 degrees C with enhanced intensity while the Eu2+ ion glow peak at 146 degrees C remains but with reduced intensity. The main glow peak at approximately 146 degrees C and 440 nm from Eu2+ ions shows significant difference from the characteristic glow peaks of Eu3+ ions. It is observed that the wavelength of the Eu2+ ion glow peak is inversely proportional to the radius of the cation of the host sulphate in alkaline-earth sulphate phosphors. By contrast the wavelengths of the Eu3+ ion glow peaks remain unchanged in different sulphates. Besides, the glow curve at approximately 146 degrees C obtained using a conventional blue sensitive reader shows simply the first order kinetics. It is concluded that the luminescence centres and distribution of traps related to Eu2+ ions are different from that of Eu3+ ions in MgSO4:Eu and MgSO4:Eu,P phosphors.
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Ding J, Tang Q, Holdcroft S. Morphologically Controlled Proton-Conducting Membranes Using Graft Polymers Possessing Block Copolymer Graft Chains. Aust J Chem 2002. [DOI: 10.1071/ch02084] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Ionic graft membranes comprising macromonomeric poly(styrene-block-styrene sulfonic acid) grafted polystyrene [PS-g-mac(PS-b-PSSA)] polymers were prepared by copolymerization of styrene and poly(styrene-block-sodium styrene sulfonate) (PS-b-PSSNa) macromonomers followed by ion-exchange. The latter were prepared with controlled molecular weight by stable free radical polymerization. Membranes exhibit varying degrees of phase separation. Membranes of low ion content are comprised of isolated ionic domains and exhibit low ionic conductivity. Increasing the number density of ionic graft chains in the polymer results in a network of nanochannels and a dramatic increase in ion conductivity. In comparison to analogous macromonomeric poly(styrene sulfonic acid) grafted polystyrene (PS-g-macPSSA) membranes, of similar ion exchange capacity (IEC) and PSSA chain length, dehydrated PS-g-mac(PS-b-PSSA) membranes consist of smaller, more densely connected ionic domains; however, water sorption and ionic conductivity are similar.
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147
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Allenspach EJ, Cullinan P, Tong J, Tang Q, Tesciuba AG, Cannon JL, Takahashi SM, Morgan R, Burkhardt JK, Sperling AI. ERM-dependent movement of CD43 defines a novel protein complex distal to the immunological synapse. Immunity 2001; 15:739-50. [PMID: 11728336 DOI: 10.1016/s1074-7613(01)00224-2] [Citation(s) in RCA: 205] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The large mucin CD43 is actively excluded from T cell/APC interaction sites, concentrating in a membrane domain distal to the site of TCR engagement. The cytoplasmic region of CD43 was necessary and sufficient for this antipodal movement. ERM cytoskeletal adaptor proteins colocalized with CD43 in this domain. An ERM dominant-negative mutant blocked the distal accumulation of CD43 and another known ERM binding protein, Rho-GDI. Inhibition of ERM function decreased the production of IL-2 and IFNgamma, without affecting PKC(theta) focusing or CD69 upregulation. These results indicate that ERM proteins organize a complex distal to the T cell/APC interaction site and provide evidence that full T cell activation may involve removal of inhibitory proteins from the immunological synapse.
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O'Herrin SM, Slansky JE, Tang Q, Markiewicz MA, Gajewski TF, Pardoll DM, Schneck JP, Bluestone JA. Antigen-specific blockade of T cells in vivo using dimeric MHC peptide. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:2555-60. [PMID: 11509595 DOI: 10.4049/jimmunol.167.5.2555] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ag-specific immune tolerance in clinical organ transplantation is currently an unrealized but critical goal of transplant biology. The specificity and avidity of multimerized MHC-peptide complexes suggests their potential ability to modulate T cell sensitization and effector functions. In this study, we examined the ability of MHC-peptide dimers to modulate T cell function both in vitro and in vivo. Soluble MHC dimers induced modulation of surface TCR expression and inhibited T cell cytolytic activity at nanomolar concentrations in vitro. Furthermore, engagement of TCR by soluble dimers resulted in phosphorylation of the TCR zeta-chain and recruitment and phosphorylation of zeta-associated protein-70 to the signaling complex, the latter of which increased upon dimer cross-linking. Significantly, Ag-specific inhibition of an alloreactive TCR-transgenic T cell population in vivo resulted in consequent outgrowth of an allogeneic tumor. The prolonged Ag-specific suppression of expansion and/or effector function of cognate T cells in vivo suggests that soluble MHC dimers may be a means of inducing sustained Ag-specific T cell unresponsiveness in vivo.
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MESH Headings
- Animals
- Cytotoxicity, Immunologic
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Dimerization
- H-2 Antigens/chemistry
- H-2 Antigens/metabolism
- Humans
- Immune Tolerance
- In Vitro Techniques
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Mice, Transgenic
- Nuclear Proteins
- Protein-Tyrosine Kinases/metabolism
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/metabolism
- Signal Transduction
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- Transplantation Immunology
- ZAP-70 Protein-Tyrosine Kinase
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Tang Q, Chen W, Gonzales MS, Finch J, Inoue H, Bowden GT. Role of cyclic AMP responsive element in the UVB induction of cyclooxygenase-2 transcription in human keratinocytes. Oncogene 2001; 20:5164-72. [PMID: 11526505 DOI: 10.1038/sj.onc.1204667] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2001] [Revised: 05/17/2001] [Accepted: 05/24/2001] [Indexed: 11/10/2022]
Abstract
It has been shown that UVB irradiation induces expression of COX-2 and up-regulation of COX-2 plays a functional role in UVB tumor promotion. In this study, we examined the cis-elements in the human COX-2 promoter that may be responsible for the UVB induction of COX-2. Analyses with the COX-2 promoter region revealed that the cyclic AMP responsive element near the TATA box was essential for both basal and UVB induced COX-2 expression. This was further supported by studies using a dominant negative mutant of CREB, which strongly inhibited the activity of COX-2 promoter. Electrophoretic mobility shift assays indicated that CREB and ATF-1 were the major proteins binding to the COX-2 CRE. CREB and ATF-1 were phosphorylated upon UVB treatment, and SB202190, a p38 MAPK inhibitor, decreased the phosphorylation of CREB/ATF-1 and suppressed COX-2 promoter activity. In contrast, treatment with forskolin, an activator of adenylyl cyclase, led to phosphorylation of CREB and ATF-1 and activation of COX-2 promoter. Finally, enhanced binding of phospho-CREB/ATF-1 to the COX-2 CRE was observed after UVB induction. Thus, one signaling pathway for UVB induction of human COX-2 involves activation of p38, subsequent phosphorylation of CREB/ATF-1, and activation of the COX-2 CRE through enhanced binding of phosphorylated CREB/ATF-1.
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150
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Abstract
Membrane proteins and lipids often appear to be distributed in patches on the cell surface. These patches are often assumed to be membrane domains, arising from specific molecular associations. However, a computer simulation (Gheber and Edidin, 1999) shows that membrane patchiness may result from a combination of vesicle trafficking and dynamic barriers to lateral mobility. The simulation predicts that the steady-state patches of proteins and lipids seen on the cell surface will decay if vesicle trafficking is inhibited. To test this prediction, we compared the apparent sizes and intensities of patches of class I HLA molecules, integral membrane proteins, before and after inhibiting endocytic vesicle traffic from the cell surface, either by incubation in hypertonic medium or by expression of a dominant-negative mutant dynamin. As predicted by the simulation, the apparent sizes of HLA patches increased, whereas their intensities decreased after endocytosis and vesicle trafficking were inhibited.
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