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Cai W, Tao J, Zhang X, Tian X, Liu T, Feng X, Bai J, Yan C, Han Y. ASSA14-03-18 Contribution of Homeostatic Chemokines CCL19 and CCL21 and their Receptor CCR7 to Coronary Artery Disease. BRITISH HEART JOURNAL 2015. [DOI: 10.1136/heartjnl-2014-307109.36] [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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Sun M, Yan C, Tian X, Li Y, Tao J, Han Y. ASSA14-03-25 Cellular repressor of E1A-stimulated genes antagonises inflammation and promotes autophagy via lysosome biogenesis in mouse macrophages. BRITISH HEART JOURNAL 2015. [DOI: 10.1136/heartjnl-2014-307109.43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Jiang Z, Tang Y, Tian X. 345 LOSS OF Brm AND Baf170, COMPONENTS OF THE ATP-DEPENDENT CHROMATIN REMODELING COMPLEX, FACILITATES REPROGRAMMING OF SOMATIC CELL. Reprod Fertil Dev 2015. [DOI: 10.1071/rdv27n1ab345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The SWI/SNF [SWItch/Sucrose NonFermentable; also known as BAF (Brg/Brahma-associated factors)] ATP-dependent chromatin remodelling complexes are epigenetic modifiers that change the structure of chromatin, and thereby modulate gene transcription. The BAF chromatin remodeling complexes undergo progressive changes in subunit composition during cellular differentiation. In embryonic stem cells (ESC), BAF complex, esBAF, contains Brg1 and Baf155, which are crucial for ESC self-renewal and also facilitate induced pluripotent stem cell (iPSC) reprogramming from somatic cells. Here we sought to determine the roles of somatic BAF components (Brm and Baf170, homologues of Brg1 and Baf155, respectively) in mouse iPSC reprogramming through shRNA-mediated knockdown studies. We found that the expression of Brm and Baf170 were inhibited in reprogramming by Janus kinase/signal transducer and activator of transcription 3 (Jak/Stat3) activity, which is essential for pluripotency establishment. We further found that knockdown of Brm and Baf170 in mouse somatic cells promotes reprogramming efficiency. Specifically, loss of Brm and Baf170 during early (Days 3 and 6 after initial iPSC induction) and later-stage (Day 9) reprogramming, respectively, improves the numbers of iPSC colonies formed. These also led to significant upregulation of pluripotent genes, including Sox2, Nanog, Fgf5, and Tbx3. Although the somatic Brm and Baf170 are believed to be absent in ESC, the expression levels of Nanog and Tbx3 were increased significantly by knockdown of either Brm or Baf170 in ESC. Finally, we showed that inhibition of these somatic BAF components also promotes complete reprogramming of partially reprogrammed cells (pre-iPSC). These data suggest that inhibiting somatic BAF complex improved complete reprogramming by facilitating the activation of the pluripotency circuitry. A reduced activity of the somatic BAF complex constitutes part of the Stat3 regulated epigenetic changes during pluripotency establishment.
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Chen MK, Cai MY, Luo RZ, Tian X, Liao QM, Zhang XY, Han JD. Overexpression of p300 correlates with poor prognosis in patients with cutaneous squamous cell carcinoma. Br J Dermatol 2014; 172:111-9. [PMID: 24975674 DOI: 10.1111/bjd.13226] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND It has been suggested that the p300 transcriptional coactivator participates in the regulation of a wide range of cell biological processes, and mutations in p300 have been identified in various cancers. OBJECTIVES To investigate p300 expression in cutaneous squamous cell carcinoma (cSCC) tissues and its effect on the outcome of patients with cSCC. METHODS Immunohistochemistry (IHC) was performed on a tissue microarray to investigate p300 expression levels in cSCC tissues. Receiver operating characteristic (ROC) curve analysis, Kaplan-Meier plots and a Cox proportional hazards regression model were used to analyse the data. RESULTS Based on the ROC curves, we defined the cut-off score for high p300 expression as > 55% of tumour cells positively stained. High expression of p300 was observed in 86 of 165 (52·1%) of the cSCC samples and six of 30 (20%) of the adjacent normal skin tissue samples (P < 0·001). High expression of p300 was positively correlated with lymph node metastasis (P = 0·006) and advanced clinical stage (P < 0·001). In univariate survival analysis, high expression of p300 was correlated with poor patient outcomes in terms of recurrence-free survival (P = 0·006) and overall survival (P < 0·001). Moreover, p300 expression was evaluated as an independent prognostic factor in a multivariate analysis (P = 0·004). CONCLUSIONS Our results indicate that high p300 expression is associated with aggressive features of cSCC and suggest that p300 expression, as examined by IHC, will be a promising biomarker for predicting clinical outcomes in patients with cSCC.
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Xiang Y, Liu T, Yang H, Gao F, Xiang H, Manyande A, Tian Y, Tian X. NRG1-ErbB signalling promotes microglia activation contributing to incision-induced mechanical allodynia. Eur J Pain 2014; 19:686-94. [PMID: 25159022 DOI: 10.1002/ejp.590] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2014] [Indexed: 01/23/2023]
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Zhang S, Shu X, Tian X, Chen F, Lu X, Wang G. Enhanced formation and impaired degradation of neutrophil extracellular traps in dermatomyositis and polymyositis: a potential contributor to interstitial lung disease complications. Clin Exp Immunol 2014; 177:134-41. [PMID: 24611519 DOI: 10.1111/cei.12319] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2014] [Indexed: 01/23/2023] Open
Abstract
Dermatomyositis (DM) and polymyosits (PM) are systemic autoimmune diseases whose pathogeneses remain unclear. Neutrophil extracellular traps (NETs) are reputed to play an important role in the pathogenesis of autoimmune diseases. This study tests the hypothesis that NETs may be pathogenic in DM/PM. Plasma samples from 97 DM/PM patients (72 DM, 25 PM) and 54 healthy controls were tested for the capacities to induce and degrade NETs. Plasma DNase I activity was tested to further explore possible reasons for the incomplete degradation of NETs. Results from 35 DM patients and seven PM patients with interstitial lung disease (ILD) were compared with results from DM/PM patients without ILD. Compared with control subjects, DM/PM patients exhibited a significantly enhanced capacity for inducing NETs, which was supported by elevated levels of plasma LL-37 and circulating cell-free DNA (cfDNA) in DM/PM. NETs degradation and DNase I activity were also decreased significantly in DM/PM patients and were correlated positively. Moreover, DM/PM patients with ILD exhibited the lowest NETs degradation in vitro due to the decrease in DNase I activity. DNase I activity in patients with anti-Jo-1 antibodies was significantly lower than in patients without. Glucocorticoid therapy seems to improve DNase I activity. Our findings demonstrate that excessively formed NETs cannot be degraded completely because of decreased DNase I activity in DM/PM patients, especially in patients with ILD, suggesting that abnormal regulation of NETs may be involved in the pathogenesis of DM/PM and could be one of the factors that initiate and aggravate ILD.
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Li XX, Li J, Sun XJ, Cai LY, Li YC, Tian X, Li JR. Preparation and malachite green adsorption behavior of polyurethane/chitosan composite foam. J CELL PLAST 2014. [DOI: 10.1177/0021955x14542538] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A series of Polyurethane/Chitosan composite foam with different chitosan content of 5–25 wt% was prepared, and their adsorption performance of malachite green (MG) in aqueous solutions was investigated by pH values, contact time, temperatures and chitosan content. It was observed that Polyurethane/Chitosan composite foam exhibited well-developed open cell structures. Malachite green adsorption capacities of the composite foam increased with the increment of chitosan content in composite foam. Polyurethane/Chitosan composite foam with 20% chitosan content exhibited a maximum removal capacity of 16.67 mg/g and 95.60% MG removal efficiency. In addition, MG adsorption capacities of composite foam increased with pH value increase, 30℃ was the optimum temperature, which affects the adsorption process, and the adsorption maximum was attained within 12 hours. The result of SEM showed the prepared composite foam possess well-developed open cell structures. The MG adsorption kinetics and equilibrium isotherm of the composite foam were well described with the pseudo-second order kinetic model and Langmuir isotherm model, respectively. This work provided an attractive adsorbent for removing of the hazardous materials from water.
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Adamson P, Anghel I, Aurisano A, Barr G, Bishai M, Blake A, Bock GJ, Bogert D, Cao SV, Castromonte CM, Cherdack D, Childress S, Coelho JAB, Corwin L, Cronin-Hennessy D, de Jong JK, Devan AV, Devenish NE, Diwan MV, Escobar CO, Evans JJ, Falk E, Feldman GJ, Frohne MV, Gallagher HR, Gomes RA, Goodman MC, Gouffon P, Graf N, Gran R, Grzelak K, Habig A, Hahn SR, Hartnell J, Hatcher R, Himmel A, Holin A, Huang J, Hylen J, Irwin GM, Isvan Z, James C, Jensen D, Kafka T, Kasahara SMS, Koizumi G, Kordosky M, Kreymer A, Lang K, Ling J, Litchfield PJ, Lucas P, Mann WA, Marshak ML, Mayer N, McGivern C, Medeiros MM, Mehdiyev R, Meier JR, Messier MD, Michael DG, Miller WH, Mishra SR, Moed Sher S, Moore CD, Mualem L, Musser J, Naples D, Nelson JK, Newman HB, Nichol RJ, Nowak JA, O'Connor J, Orchanian M, Pahlka RB, Paley J, Patterson RB, Pawloski G, Perch A, Phan-Budd S, Plunkett RK, Poonthottathil N, Qiu X, Radovic A, Rebel B, Rosenfeld C, Rubin HA, Sanchez MC, Schneps J, Schreckenberger A, Schreiner P, Sharma R, Sousa A, Tagg N, Talaga RL, Thomas J, Thomson MA, Tian X, Timmons A, Tognini SC, Toner R, Torretta D, Tzanakos G, Urheim J, Vahle P, Viren B, Weber A, Webb RC, White C, Whitehead L, Whitehead LH, Wojcicki SG, Zwaska R. Combined analysis of νμ disappearance and νμ→νe appearance in MINOS using accelerator and atmospheric neutrinos. PHYSICAL REVIEW LETTERS 2014; 112:191801. [PMID: 24877929 DOI: 10.1103/physrevlett.112.191801] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Indexed: 06/03/2023]
Abstract
We report on a new analysis of neutrino oscillations in MINOS using the complete set of accelerator and atmospheric data. The analysis combines the ν(μ) disappearance and ν(e) appearance data using the three-flavor formalism. We measure |Δm(32)(2)| = [2.28-2.46] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.35-0.65 (90% C.L.) in the normal hierarchy, and |Δm(32)(2)| = [2.32-2.53] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.34-0.67 (90% C.L.) in the inverted hierarchy. The data also constrain δ(CP), the θ(23} octant degeneracy and the mass hierarchy; we disfavor 36% (11%) of this three-parameter space at 68% (90%) C.L.
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Ye W, Du L, Tian X. Synthesis and Properties of a Novel Intumescent Flame Retardant and its Application in LLDPE. INT POLYM PROC 2014. [DOI: 10.3139/217.2716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
In this study, a novel phosphorus-containing flame retardant (IFR) of spirocyclic pentaerythritol diphosphonate dinitroguanidine (SPDD) was successfully synthesized, which was characterized by 1H NMR, 31P NMR and FTIR spectra. At the same time, the SPDD was used in LLDPE to prepare flame-retardant materials whose flammability and thermal behavior were studied by thermogravimetric analysis (TGA), limiting oxygen index (LOI) and scanning electron microscopy (SEM). The TGA data showed that SPDD could effectively enhance the thermal stability and char residue of LLDPE/IFR composite. And with the increase of SPDD, the LOI value of LLDPE/IFR increases obviously. When SPDD reached 30 wt%, the LOI value of LLDPE/IFR reaches 31 %. The SEM also shows the surface of intumescent chars of LLDPE/IFR (30 %) has many sphere-like swollen bubbles.
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Chen Z, Wang G, Zhai X, Hu Y, Gao D, Ma L, Yao J, Tian X. Selective inhibition of protein kinase C β2 attenuates the adaptor P66 Shc-mediated intestinal ischemia-reperfusion injury. Cell Death Dis 2014; 5:e1164. [PMID: 24722289 PMCID: PMC5424109 DOI: 10.1038/cddis.2014.131] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Revised: 01/02/2014] [Accepted: 02/28/2014] [Indexed: 12/15/2022]
Abstract
Apoptosis is a major mode of cell death occurring during ischemia–reperfusion (I/R) induced injury. The p66Shc adaptor protein, which is mediated by PKCβ, has an essential role in apoptosis under oxidative stress. This study aimed to investigate the role of PKCβ2/p66Shc pathway in intestinal I/R injury. In vivo, ischemia was induced by superior mesenteric artery occlusion in mice. Ruboxistaurin (PKCβ inhibitor) or normal saline was administered before ischemia. Then blood and gut tissues were collected after reperfusion for various measurements. In vitro, Caco-2 cells were challenged with hypoxia–reoxygenation (H/R) to simulate intestinal I/R. Translocation and activation of PKCβ2 were markedly induced in the I/R intestine. Ruboxistaurin significantly attenuated gut damage and decreased the serum levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Pharmacological blockade of PKCβ2 suppressed p66Shc overexpression and phosphorylation in the I/R intestine. Gene knockdown of PKCβ2 via small interfering RNA (siRNA) inhibited H/R-induced p66Shc overexpression and phosphorylation in Caco-2 cells. Phorbol 12-myristate 13-acetate (PMA), which stimulates PKCs, induced p66Shc phosphorylation and this was inhibited by ruboxistaurin and PKCβ2 siRNA. Ruboxistaurin attenuated gut oxidative stress after I/R by suppressing the decreased expression of manganese superoxide dismutase (MnSOD), the exhaustion of the glutathione (GSH) system, and the overproduction of malondialdehyde (MDA). As a consequence, ruboxistaurin inhibited intestinal mucosa apoptosis after I/R. Therefore, PKCβ2 inhibition protects mice from gut I/R injury by suppressing the adaptor p66Shc-mediated oxidative stress and subsequent apoptosis. This may represent a novel therapeutic approach for the prevention of intestinal I/R injury.
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Liu Y, Tian X, Wang R, Wagenknecht T, Liu Z, Wayne Chen S. Ligand-Dependent Conformational Changes in the Cardiac Ryanodine Receptor. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Tian X, Liang XM, Song GM, Zhao Y, Yang XL. Maggot debridement therapy for the treatment of diabetic foot ulcers: a meta-analysis. J Wound Care 2013; 22:462-9. [PMID: 24005780 DOI: 10.12968/jowc.2013.22.9.462] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
OBJECTIVE To assess the potential efficacy of maggot debridement therapy (MDT) compared with standard care for diabetic foot ulcers (DFUs). METHOD A meta-analysis was performed on the evidence for MDT for DFUs. Databases, including PubMed, Web of Science, the Cochrane Library, EMbase, EBSCOhost, Springer Link, ScienceDirect and Ovid-Medline, were electronically searched for randomised controlled trials, case-control studies and controlled clinical trials, up to 31 December 2012, and relevant references of the included articles were also manually searched. The literature was screened, the data were extracted and the methodological quality of the included studies was assessed. Meta-analyses were performed on the included data, for the outcomes healing rate, time to healing, incidence of infection, amputation rate and antibiotic-free days or antibiotics usage. RESULTS Overall, four studies comparing MDT with standard therapy on a total of 356 participants were included. The results of meta-analyses suggested that the MDT group was significantly superior to the control group in the percentage of DFUs to achieve full healing (RR=1.8, 95%CI=1.07; 3.02; p=0.03), amputation rate (RR=0.41, 95%CI=0.20; 0.85; p=0.02), time to healing (RR=-3.70, 95%CI=-5.76; -1.64; p=0.0004) and number of antibiotic-free days (126.8 ± 30.3 days vs 81.9 ± 42.1 days; p=0.001); however, collated differences in incidence of infection after intervention revealed no evidence of a difference between the MDT and control groups (RR=0.82, 95%CI=0.65; 1.04, p=0.10). CONCLUSION Although MDT may be a scientific and effective therapy in treatment of DFUs, the evidence is too weak to routinely recommend it for treatment. Large studies and sample sizes are needed to assess the efficacy and safety of MDT in the treatment of DFUs. DECLARATION OF INTEREST There were no external sources of funding for this study. The authors have no conflicts of interest to declare with regard to this work or its contents. X. Tian and X.M. Liang contributed equally to this work.
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Kojonazarov B, Lang M, Tian X, Kalymbetov A, Weißmann N, Grimminger F, Kretschmer A, Stasch JP, Ghofrani HA, Seeger W, Schermuly R. Wirkung des sGC-Stimulators Riociguat auf das pulmonalvaskuläre und rechtsventrikuläre Remodeling bei schwerer pulmonal-arterieller Hypertonie. Pneumologie 2013. [DOI: 10.1055/s-0033-1344748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Shepardson D, Marks SM, Chesson H, Kerrigan A, Holland DP, Scott N, Tian X, Borisov AS, Shang N, Heilig CM, Sterling TR, Villarino ME, Mac Kenzie WR. Cost-effectiveness of a 12-dose regimen for treating latent tuberculous infection in the United States. Int J Tuberc Lung Dis 2013; 17:1531-7. [PMID: 24200264 PMCID: PMC5451112 DOI: 10.5588/ijtld.13.0423] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
SETTING A large randomized controlled trial recently showed that for treating latent tuberculous infection (LTBI) in persons at high risk of progression to tuberculosis (TB) disease, a 12-dose regimen of weekly rifapentine plus isoniazid (3HP) administered as directly observed treatment (DOT) can be as effective as 9 months of daily self-administered isoniazid (9H). OBJECTIVES To assess the cost-effectiveness of 3HP compared to 9H. DESIGN A computational model was designed to simulate individuals with LTBI treated with 9H or 3HP. Costs and health outcomes were estimated to determine the incremental costs per active TB case prevented and per quality-adjusted life year (QALY) gained by 3HP compared to 9H. RESULTS Over a 20-year period, treatment of LTBI with 3HP rather than 9H resulted in 5.2 fewer cases of TB and 25 fewer lost QALYs per 1000 individuals treated. From the health system and societal perspectives, 3HP would cost respectively US$21,525 and $4294 more per TB case prevented, and respectively $4565 and $911 more per QALY gained. CONCLUSIONS 3HP may be a cost-effective alternative to 9H, particularly if the cost of rifapentine decreases, the effectiveness of 3HP can be maintained without DOT, and 3HP treatment is limited to those with a high risk of progression to TB disease.
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Zhou Y, Li F, Tian X, Wang B, Ding M, Pang H. Changes in phosphatidylinositol 3-kinase 55 kDa gamma expression and subcellular localization may be caspase 6 dependent in paraquat-induced SH-SY5Y apoptosis. Hum Exp Toxicol 2013; 33:761-71. [PMID: 24130211 DOI: 10.1177/0960327113499044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The neurotoxin paraquat (PQ) causes apoptosis of dopaminergic neurons in mammalian cell culture and animal models, mimicking an important pathological feature of Parkinson's disease (PD). The phosphoinositide 3-kinase (PI3K)/Akt pathway is critical for several major survival signals in central nervous system neurons. Phosphatidylinositol 3-kinase 55 kDa gamma (p55PIK) is a regulatory subunit of PI3Ks with important roles in cell proliferation, antiapoptosis, and cell cycle progression. However, p55PIK involvement in mechanisms regarding progression and maintenance of neurodegenerative diseases is largely undetermined. We used PQ-induced apoptosis in human dopaminergic SH-SY5Y cells to investigate the association between p55PIK expression levels, subcellular location, and apoptosis. p55PIK expression was reduced in SH-SY5Y cells and p55PIK messenger RNA and protein expression levels were decreased after PQ treatment. Apoptosis induced by PQ was associated with caspase activation and decreased p55PIK expression. Restoration of p55PIK expression was observed after coincubation with a caspase inhibitor. Overexpressed full-length p55PIK in SH-SY5Y and human embryonic kidney 293 cells showed specific distribution in the nucleus and was cleaved in vitro by recombinant caspase 6 (C6), but not C3 and C7. A p55PIK construct lacking 24 N-terminal amino acids (N24) was tested for the presence of a potential C6-recognizable sequence and was found to express its proteins outside the nucleus. The results suggest that p55PIK may be involved in PQ-induced apoptosis signal transduction and that N24 is crucial for p55PIK subcellular localization. Thus, p55PIK could be a substrate of activated C6 during apoptosis, leading to loss of original biological functions and redistribution to disturb cell cycle progression.
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Tian X, Strassmann JE, Queller DC. A conserved extraordinarily long serine homopolymer in Dictyostelid amoebae. Heredity (Edinb) 2013; 112:215-8. [PMID: 24084645 DOI: 10.1038/hdy.2013.96] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 06/12/2012] [Accepted: 08/30/2013] [Indexed: 12/19/2022] Open
Abstract
Eukaryotic protein sequences often contain amino-acid homopolymers that consist of a single amino acid repeated from several to dozens of times. Some of these are functional but others may persist largely because of high expansion rates due to DNA slippage. However, very long homopolymers with over a hundred repeats are very rare. We report an extraordinarily long homopolymer consisting of 306 tandem serine repeats from the single-celled eukaryote Dictyostelium discoideum, which also has a multicellular stage. The gene has a paralog with 132 repeats and orthologs, also with high serine repeat numbers, in various other Dictyostelid species. The conserved gene structure and protein sequences suggest that the homopolymer is functional. The high codon diversity and very poor alignment of serine codons in this gene between species similarly indicate functionality. This is because the serine homopolymer is conserved despite much DNA sequence change. A survey of other very long amino-acid homopolymers in eukaryotes shows that high codon diversity is the rule, suggesting that these too may be functional.
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Dong X, Xu X, Miao J, Li L, Zhang D, Mi X, Liu C, Tian X, Melchinger AE, Chen S. Fine mapping of qhir1 influencing in vivo haploid induction in maize. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2013; 126:1713-20. [PMID: 23539086 DOI: 10.1007/s00122-013-2086-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 03/11/2013] [Indexed: 05/18/2023]
Abstract
Production of haploids by the in vivo haploid induction method has now become routine for generating new inbred lines in maize. In previous studies, a major quantitative trait locus (QTL) (qhir1) located in bin 1.04 was detected, explaining up to 66 % of the genotypic variance for haploid induction rate (HIR). Our objectives were to (1) fine-map qhir1 and (2) identify closely linked markers useful for marker-assisted breeding of new inducers. For this purpose, we screened a mapping population of 14,375 F2 plants produced from a cross between haploid inducer UH400 and non-inducer line 1680 to identify recombinants. Based on sequence information from the B73 reference genome, markers polymorphic between the two parents were developed to conduct fine mapping with these recombinants. A progeny test mapping strategy was applied to accurately determine the HIR of the 14 recombinants identified. Furthermore, F3 progeny of recombinant F2 plants were genotyped and in parallel evaluated for HIR. We corroborated earlier studies in that qhir1 has both a significantly positive effect on HIR but also a strong selective disadvantage, as indicated by significant segregation distortion. Altogether, we were able to narrow down the qhir1 locus to a 243 kb region flanked by markers X291 and X263.
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Tian X, Smitherman C, Christiansen O, Frush D, Samei E. TU-C-103-07: Prospective Estimation of Diagnostic Performance and Radiation Dose for Individual CT Scans. Med Phys 2013. [DOI: 10.1118/1.4815396] [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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Zhang ZY, Xuan Y, Jin XY, Tian X, Wu R. CASP-9 gene functional polymorphisms and cancer risk: a large-scale association study plus meta-analysis. GENETICS AND MOLECULAR RESEARCH 2013; 12:3070-8. [PMID: 23479167 DOI: 10.4238/2013.february.28.22] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We investigated the association between CASP-9 polymorphisms and susceptibility to neoplasm. Fourteen studies with a total of 2733 neoplasm cases and 3352 healthy controls were included. Meta-analysis showed that the rs4645981 T allele and the rs4645981 T allele carrier were positively associated with neoplasm susceptibility [odds ratio (OR) = 1.43, 95% confidence interval (95%CI) = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009, respectively]. However, the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might decrease the risk of cancer (OR = 0.72, 95%CI = 0.58-0.89, P = 0.003; OR = 0.76, 95%CI = 0.63-0.92, P = 0.004; OR = 0.20, 95%CI = 0.09-0.45, P < 0.0001; OR = 0.21, 95%CI = 0.06-0.75, P = 0.02, respectively). There was no significant association between rs1263, rs1052571, rs2308950, rs4645978, rs4645980, rs4645982, and rs4646018 and cancer risk (all P > 0.05). In conclusion, this meta-analysis suggests that CASP-9 gene polymorphisms are involved in the pathogenesis of various cancers. The rs4645981 T allele and the rs4645981 T allele carrier might increase the risk of cancer, but the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might be protective.
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Tian X, Zheng Y, Chintaluri K, Meng B. First Report of Impatiens necrotic spot virus on Hiemalis Begonia (Begonia × hiemalis) in Canada. PLANT DISEASE 2013; 97:291. [PMID: 30722332 DOI: 10.1094/pdis-09-12-0868-pdn] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Impatiens necrotic spot virus (INSV) is a member of the genus Tospovirus, and one of the prevalent viruses infecting ornamental plants, including begonia. Since the late 1980s, it has caused dramatic and unusual diseases on many flower crops, leading to considerable economic losses to the greenhouse floriculture industry (1). The western flower thrips, Frankliniella occidentalis (Pergande), is the only species currently known to vector INSV (1). In spring 2012, stunted plant growth and necrotic spots were observed on leaves of all Hiemalis begonias (Begonia × hiemalis Fotsch.) in a greenhouse in southwest Ontario, Canada. Initial symptoms were mosaic patterns, followed by necrotic spots on leaves, concentric rings, then necrotic areas on flowers, stem and vein necrosis, and finally stunting and burning of foliage similar to damage caused by sunburn or chemical injury. Thrips were observed colonizing nearby begonia plants. Leaf tissue from five symptomatic plants tested positive for INSV in a double-antibody sandwich (DAS)-ELISA with INSV-specific ImmunoStrips (Agdia Inc., Elkhart, IN). To confirm this, five of the leaf samples that were found to be positive for INSV in ELISA tests were mechanically inoculated to 10 plants of Hiemalis Begonia. Out of the 10 inoculated plants, eight produced necrotic local lesions and necrotic spots that are typical of INSV infection, followed by systemic infection of upper leaves 30 days after inoculation. The presence of INSV in the eight symptomatic plants was confirmed using the commercial INSV Pocket Diagnostic Kit (Forsite Diagnostics Ltd., York, UK) according to the manufacturer's instructions. Results showed that all eight symptomatic plants were positive for INSV. The other two plants were asymptomatic and tested negative for INSV. To further confirm the identity of this virus, total RNAs were isolated from symptomatic leave of begonia plants using TRIzol reagent (Invitrogen, Life Technologies Grand Island, NY) and amplified using reverse transcription (RT)-PCR analysis. A pair of primers was designed based on the consensus sequence of the N gene for a number of isolates retrieved from GenBank. These primers were INSV-F2286 (5'CCAAGCTCAACATGTTTAGC 3', nt positions 2286 to 2305 of AB109100) and INSV-R2604 (5'ACTGCATCTTGCCTATCCTT 3', nt positions 2664 to 2683 of AB109100). The expected amplification product of 398 bp was obtained, and was cloned into the vector pGEM-T Easy (Promega Corp., Madison, WI). Two clones were sequenced using the vector primer M13Forward. The sequences of these two clones were identical and the sequence was deposited in GenBank (Accession No. JX846907). BLAST analysis indicated that the sequence was 98 to 99% identical to INSV isolates from Japan (AB109100), the United States (D00914), and the Netherlands (X66972). To our knowledge, this is the first report of INSV infection in Begonia × hiemalis in Canada. This finding provides further evidence for the spread of the virus within North America. Further studies are required to determine the impact of INSV on the begonia industry in Canada and to determine viable management strategies, if necessary. Reference: (1) M. L. Daughtrey et al. Plant Dis. 81:1220, 1997.
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Tian X, Diaz FJ. Acute dietary zinc deficiency before conception compromises oocyte epigenetic programming and disrupts embryonic development. Dev Biol 2013; 376:51-61. [PMID: 23348678 DOI: 10.1016/j.ydbio.2013.01.015] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 01/12/2013] [Accepted: 01/15/2013] [Indexed: 01/09/2023]
Abstract
Recent findings show that zinc is an important factor necessary for regulating the meiotic cell cycle and ovulation. However, the role of zinc in promoting oocyte quality and developmental potential is not known. Using an in vivo model of acute dietary zinc deficiency, we show that feeding a zinc deficient diet (ZDD) for 3-5 days before ovulation (preconception) dramatically disrupts oocyte chromatin methylation and preimplantation development. There was a dramatic decrease in histone H3K4 trimethylation and global DNA methylation in zinc deficient oocytes. Moreover, there was a 3-20 fold increase in transcript abundance of repetitive elements (Iap, Line1, Sineb1, Sineb2), but a decrease in Gdf9, Zp3 and Figla mRNA. Only 53% and 8% of mature eggs reached the 2-cell stage after IVF in animals receiving a 3 and 5 days ZDD, respectively, while a 5 day ZDD in vivo reduced the proportion of 2-cells to 49%. In vivo fertilized 2-cell embryos cultured in vitro formed fewer (38%) blastocysts compared to control embryos (74%). Likewise, fewer blastocyst and expanded blastocyst were collected from the reproductive tract of zinc deficient animals on day 3.5 of pregnancy. This could be due to a decrease in Igf2 and H19 mRNA in ZDD blastocyst. Supplementation with a methyl donor (SAM) during IVM restored histone H3K4me3 and doubled the IVF success rate from 17% to 43% in oocytes from zinc deficient animals. Thus, the terminal period of oocyte development is extremely sensitive to perturbation in dietary zinc availability.
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Zhang ZY, Xuan Y, Jin XY, Tian X, Wu R. Meta-analysis demonstrates association of XRCC1 genetic polymorphism Arg399Gln with esophageal cancer risk in the Chinese population. GENETICS AND MOLECULAR RESEARCH 2013; 12:2567-77. [PMID: 23359058 DOI: 10.4238/2013.january.16.2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We made a meta-analysis of the association between X-ray cross-complementing gene 1 (XRCC1) genetic polymorphism Arg399Gln and esophageal cancer (EC) risk. Statistical analysis was performed with the Review Manager version 4.2.8 software program and STATA version 11.0. We selected 16 case-control studies for this meta-analysis, including 3591 EC cases and 5752 controls. Overall, the Gln399 allele was not associated with EC risk, compared with the Arg399 allele in the populations included in the analysis. However, stratified analysis revealed that the Gln399 allele was associated with increased EC risk among the Chinese population in a recessive model [odds ratio (OR) = 1.42; 95% confidence interval (95%CI) = 1.07-1.90; P = 0.02 for heterogeneity] and by homozygote contrast (OR = 1.43; 95%CI = 1.05-1.96; P = 0.02 for heterogeneity), particularly for the tumor histology of squamous cell carcinoma (OR = 1.46; 95%CI = 1.10-1.95 for the recessive model and OR = 1.42; 95%CI = 1.03-1.95 for the homozygote contrast). We conclude that the XRCC1 Arg399Gln polymorphism has potential as a biomarker for EC susceptibility in the Chinese population, particularly for squamous cell carcinoma.
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Zhang ZY, Xuan Y, Jin XY, Tian X, Wu R. A literature-based systematic HuGE review and meta-analysis show that CASP gene family polymorphisms are associated with risk of lung cancer. GENETICS AND MOLECULAR RESEARCH 2013; 12:3057-69. [PMID: 23315881 DOI: 10.4238/2013.january.4.22] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The caspase (CASP) gene family is known to be involved in apoptosis, cytokine maturation, cell growth, and differentiation. A large number of single nucleotide polymorphisms (SNPs) in the CASP gene family have been increasingly recognized as important regulators in the development of lung cancer. However, this specific association is still controversial. In this Human Genome Epidemiology review and meta-analysis, we summarized the available evidence associating lung cancer with the CASP gene family. Seven studies, which included 1155 lung cancer cases and 1120 healthy controls, met the inclusion criteria and were included in our meta-analysis. In seven studies, 19 different SNPs have been studied in seven CASP genes, including CASP-1, -2, -5, -7, -8, -9, and -10. Meta-analysis results showed positive associations between heterozygote (A/G) of rs507879 in the CASP-5 gene, the T allele of rs12415607 in the CASP-7 gene, and the T allele and T carrier (C/T+T/T) of rs4645981 in the CASP-9 gene with lung cancer susceptibility [odds ratio (OR) = 1.83, 95% confidence interval (95%CI) = 1.07-3.12, P = 0.03; OR = 1.18, 95%CI = 1.02-1.37, P = 0.03; OR = 1.43, 95%CI = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009; respectively]. However, we found that homozygote (G/G) of rs2227310 in the CASP-7 gene, del allele, heterozygote (ins/del), and del carrier (ins/del + del/del) of rs3834129 in CASP-8 could be protective factors for lung cancer (OR = 0.17, 95%CI = 0.14-0.21, P = 0.0003; OR = 0.83, 95%CI = 0.72-0.97, P = 0.02; OR = 0.74, 95%CI = 0.64-0.85, P < 0.0001; OR = 0.81, 95%CI = 0.71-0.93, P = 0.002; respectively). In conclusion, based on this meta-analysis, we suggest that SNPs in CASP-5, -7, -8, and -9 are associated with susceptibility to lung cancer.
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Fu X, Li S, Jia G, Gou L, Tian X, Sun L, Ling X, Lan N, Yin X, Ma R, Liu L, Liu Y. Protective effect of the nitric oxide pathway in L-citrulline renal ischaemia-reperfusion injury in rats. Folia Biol (Praha) 2013; 59:225-232. [PMID: 24485304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To observe the protective effects of L-citrulline on the renal I/R injury and elucidate the mechanisms involved, 48 rats were randomized into eight groups: Group 1: sham operated; Group 2: I/R (45 min renal ischaemia and 24 h reperfusion); Group 3: I/R + L-citrulline (300 mg/kg, i.g.); Group 4: I/R + L-citrulline (600 mg/kg, i.g.); Group 5: I/R + L-citrulline (900 mg/kg, i.g.); Group 6: I/R + normal saline (NS, i.g.); Group 7: I/R + N sup ω nitro-L-arginine ester (L-NAME, 20 mg/kg, i.p.); Group 8: I/R + L-citrulline (900 mg/kg, i.g.) + L-NAME (20 mg/ kg, i.p.). At the end of the reperfusion period, serum was collected and the kidneys underwent histological and biochemical examinations. Our results showed that pre-treatment with L-citrulline (300, 600, and 900 mg/kg) significantly ameliorated the renal injury caused by I/R. Moreover, L-citrulline prevented induction of lipid peroxidation and increased the activity of superoxide dismutase and the levels of glutathione and nitric oxide. The I/R-induced decreases in total nitric oxide synthase activity, inducible nitric oxide activity, constitutive nitric oxide activity and endothelial nitric oxide protein expression in the renal cortex were significantly prevented. However, the L-citrulline-mediated protection was significantly antagonized by co-administration of L-NAME. These results suggested that L-citrulline administration exhibited significant protection against renal I/R injury. This protective effect, at least in part, via up-regulation of the endothelial nitric oxide protein expression and constitutive nitric oxide synthase activity, maintained production of nitric oxide at the basal level.
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Liu Y, Hiess F, Tian X, Wang R, Chen SW. The CPVT-Associated RyR2 Mutation G230C reduces the Threshold for Store Overload-Induced Ca Release (SOICR). Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.2454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Tian X, Liu Y, Liu Y, Wang R, Wagenknecht T, Liu Z, Chen SRW. Ligand-dependent conformational changes in the clamp region of the cardiac ryanodine receptor. J Biol Chem 2012; 288:4066-75. [PMID: 23258540 DOI: 10.1074/jbc.m112.427864] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Global conformational changes in the three-dimensional structure of the Ca(2+) release channel/ryanodine receptor (RyR) occur upon ligand activation. A number of ligands are able to activate the RyR channel, but whether these structurally diverse ligands induce the same or different conformational changes in the channel is largely unknown. Here we constructed a fluorescence resonance energy transfer (FRET)-based probe by inserting a CFP after residue Ser-2367 and a YFP after residue Tyr-2801 in the cardiac RyR (RyR2) to yield a CFP- and YFP-dual labeled RyR2 (RyR2(Ser-2367-CFP/Tyr-2801-YFP)). Both of these insertion sites have previously been mapped to the "clamp" region in the four corners of the square-shaped cytoplasmic assembly of the three-dimensional structure of RyR2. Using this novel FRET probe, we monitored the extent of conformational changes in the clamp region of RyR2(Ser-2367-CFP/Tyr-2801-YFP) induced by various ligands. We also monitored the extent of Ca(2+) release induced by the same ligands in HEK293 cells expressing RyR2(Ser-2367-CFP/Tyr-2801-YFP). We detected conformational changes in the clamp region for the ligands caffeine, aminophylline, theophylline, ATP, and ryanodine but not for Ca(2+) or 4-chloro-m-cresol, although they all induced Ca(2+) release. Interestingly, caffeine is able to induce further conformational changes in the clamp region of the ryanodine-modified channel, suggesting that ryanodine does not lock RyR in a fixed conformation. Our data demonstrate that conformational changes in the clamp region of RyR are ligand-dependent and suggest the existence of multiple ligand dependent RyR activation mechanisms associated with distinct conformational changes.
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Han L, Tian X. Dynamic-average Characteristics of Late Wave of Auditory Evoked Potentials for Synaptic Malfunction Rat Model. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2012; 2005:3664-7. [PMID: 17281022 DOI: 10.1109/iembs.2005.1617277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The aim of this study is to investigate dynamic characteristics of late wave of auditory evoked potentials (AEPs) in synaptic malfunction rat model. Two dynamic characteristics relative to cognitive function were investigated which are dynamic latency and dynamic amplitude of P1. Synaptic malfunction model was made by Sprague-Dawley rats via microinjecting beta-amyloid protein (A-beta) into hippocampal CA1 area of rat. Dynamic AEPs with high background noise were recorded for both model and normal rats in experiments. Dynamic late wave were taken from dynamic AEPs using third-order correlation and wavelet technology. The dynamic-average latency and the dynamic-average amplitude of P1 in a small time window (5s) were performed as dynamic index in this study, which remain most of dynamic information because the average window was very small. Then dynamic-average latency and the dynamic-average latency of P1 were compared between synaptic malfunction rat and normal group. The results of this study have demonstrated that: (1) the dynamic-average latency of P1 for model rats prolonged remarkably than control (P<0.01, alpha =0.05); (2) the dynamic-average amplitude of P1 for model rats increased remarkably than control(P<0.01,alpha =0.05). The conclusion is that dynamic-average latency and dynamic-average amplitude in the synaptic malfunction rats model has obvious difference with normal group.
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Du W, Yue Y, Tian X. Variation of isoflavones production in red clover as related to environment, growth stage and year. ACTA ALIMENTARIA 2012. [DOI: 10.1556/aalim.41.2012.2.8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Tang Y, Tian X, Wang R, Fill M, Chen SRW. Abnormal termination of Ca2+ release is a common defect of RyR2 mutations associated with cardiomyopathies. Circ Res 2012; 110:968-77. [PMID: 22374134 DOI: 10.1161/circresaha.111.256560] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Naturally occurring mutations in the cardiac ryanodine receptor (RyR2) have been associated with both cardiac arrhythmias and cardiomyopathies. It is clear that delayed afterdepolarization resulting from abnormal activation of sarcoplasmic reticulum Ca2+ release is the primary cause of RyR2-associated cardiac arrhythmias. However, the mechanism underlying RyR2-associated cardiomyopathies is completely unknown. OBJECTIVE In the present study, we investigate the role of the NH2-terminal region of RyR2 in and the impact of a number of cardiomyopathy-associated RyR2 mutations on the termination of Ca2+ release. METHODS AND RESULTS The 35-residue exon-3 region of RyR2 is associated with dilated cardiomyopathy. Single-cell luminal Ca2+ imaging revealed that the deletion of the first 305 NH2-terminal residues encompassing exon-3 or the deletion of exon-3 itself markedly reduced the luminal Ca2+ threshold at which Ca2+ release terminates and increased the fractional Ca2+ release. Single-cell cytosolic Ca2+ imaging also showed that both RyR2 deletions enhanced the amplitude of store overload-induced Ca2+ transients in HEK293 cells or HL-1 cardiac cells. Furthermore, the RyR2 NH2-terminal mutations, A77V, R176Q/T2504M, R420W, and L433P, which are associated with arrhythmogenic right ventricular displasia type 2, also reduced the threshold for Ca2+ release termination and increased fractional release. The RyR2 A1107M mutation associated with hypertrophic cardiomyopathy had the opposite action (i.e., increased the threshold for Ca2+ release termination and reduced fractional release). CONCLUSIONS These results provide the first evidence that the NH2-terminal region of RyR2 is an important determinant of Ca2+ release termination, and that abnormal fractional Ca2+ release attributable to aberrant termination of Ca2+ release is a common defect in RyR2-associated cardiomyopathies.
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Tian X, Diaz FJ. Zinc depletion causes multiple defects in ovarian function during the periovulatory period in mice. Endocrinology 2012; 153:873-86. [PMID: 22147014 PMCID: PMC3275394 DOI: 10.1210/en.2011-1599] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Shortly before ovulation, the oocyte acquires developmental competence and granulosa cells undergo tremendous changes including cumulus expansion and luteinization. Zinc is emerging as a key regulator of meiosis in vitro, but a complete understanding of zinc-mediated effects during the periovulatory period is lacking. The present study uncovers the previously unknown role of zinc in maintaining meiotic arrest before ovulation. A zinc chelator [N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN)] caused premature germinal vesicle breakdown and associated spindle defects in denuded oocytes even in the presence of a phosphodiesterase 3A inhibitor (milrinone). TPEN also potently blocked cumulus expansion by blocking induction of expansion-related transcripts Has2, Ptx3, Ptgs2, and Tnfaip6 mRNA. Both meiotic arrest and cumulus expansion were rescued by exogenous zinc. Lack of cumulus expansion is due to an almost complete suppression of phospho-Sma- and Mad-related protein 2/3 signaling. Consistent with a decrease in phospho-Sma- and Mad-related protein 2/3 signaling, TPEN also decreased cumulus transcripts (Ar and Slc38a3) and caused a surprising increase in mural transcripts (Lhcgr and Cyp11a1) in cumulus cells. In vivo, feeding a zinc-deficient diet for 10 d completely blocked ovulation and compromised cumulus expansion. However, 42.5% of oocytes had prematurely resumed meiosis before human chorionic gonadotropin injection, underscoring the importance of zinc before ovulation. A more acute 3-d treatment with a zinc-deficient diet did not block ovulation but did increase the number of oocytes trapped in luteinizing follicles. Moreover, 23% of ovulated oocytes did not reach metaphase II due to severe spindle defects. Thus, acute zinc deficiency causes profound defects during the periovulatory period with consequences for oocyte maturation, cumulus expansion, and ovulation.
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Yu J, Mi J, Wang Y, Wang A, Tian X. Regulation of radiosensitivity by HDAC inhibitor trichostatin A in the human cervical carcinoma cell line Hela. EUR J GYNAECOL ONCOL 2012; 33:285-290. [PMID: 22873101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Histone deacetylase (HDAC) inhibitors play an important role in inducing growth arrest, differentiation, and/or apoptosis in cancer cells. Given their ability to disrupt critical biological processes in cancer cells, these agents are emerging as potential therapeutics for cancer. Recently, it has been identified that HDAC inhibitors can also efficiently enhance the radiation sensitivity of cells, both in vitro and in vivo. In this study, we investigated whether the potent HDAC inhibitor, Trichostatin A, modulates the radiation sensitivity of the human cervical carcinoma cell line Hela under hypoxic conditions. We concluded that TSA could significantly inhibit the proliferation of Hela cells in a dose-and time-dependent manner under normoxic and hypoxic conditions. Hypoxia resulted in the cervical carcinoma Hela cells resistant to TSA. The findings from clonogenic survival assays indicate that incubation with TSA for 24 hours prior to irradiation enhances the radiation sensitivity of Hela cells under hypoxic conditions. More generally, we found Hela cells under hypoxic conditions treated with TSA could significantly down-regulate the expressions of HIF-1alpha and VEGF proteins. Taken together, our results demonstrated that TSA acts as a powerful radiosensitizer in Hela cells under hypoxic conditions probably by down-regulated expression of HIF-1alpha and VEGF proteins.
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Zhou Y, Li F, Tian X, Zhu L, Yang Y, Luo X, Ren Y, Pang H. 3.019 ASSOCIATION OF PARKINSON'S DISEASE WITH SIX SNPS LOCATED ON FOUR PARK S GENES IN NORTHERN HAN CHINESE POPULATION. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70755-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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184
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Li X, Ma H, Tian X, Jin X. Elective neck dissection in papillary thyroid carcinoma patients. Acta Chir Belg 2012; 112:44-50. [PMID: 22442909 DOI: 10.1080/00015458.2012.11680794] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND This study was designed to review the diagnostic performance of cervical lymph node metastases for assessment of elective neck dissection in papillary thyroid carcinoma patients and to determine the technique (using Methylene blue dye) that demonstrated the highest success rate with regard to the detection rate and sensitivity. METHODS Preoperative 24 h, 1 mL of 1.0% methylene blue was injected into the parenchyma surrounding the primary tumor with ultrasound guidance by a 27-gauge needle. Intra-operative lymph nodes that were stained blue and/or having afferent lymphatic channels stained blue were also considered to be excised. All stained blue nodes were defined by levels, number, site and were sent for frozen and permanent section histologic analysis. RESULTS For the 132 patients who underwent methylene blue dye, 1373 lymph nodes were removed. 7 lymph nodes had negative dye results but, in the end, had metastatic lymph nodes. 120 lymph nodes had both negative dye and lymph node results. The number of blue-dye lymph nodes was 1246 and the number of pathology metastatic nodes was 1079, so the pathological diagnose accordance rate was 87.8 percent. The nodal metastases often occur at level VI, IV, III, then in level II, and less in level I and V. CONCLUSIONS This method using methylene blue dye is feasible technically and is safe, and the findings correlate with cervical lymph node status. According to the pattern of blue dye lymph nodes and frozen-section histologic analysis, performing elective neck dissection is a reliable, safe surgical procedure for PTC.
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Jia Y, Wang C, Zhao G, Guo P, Tian X. The possibility of using cyanobacterial bloom materials as a medium for white rot fungi. Lett Appl Microbiol 2011; 54:96-101. [DOI: 10.1111/j.1472-765x.2011.03178.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Beca S, Helli PB, Simpson JA, Zhao D, Farman GP, Jones P, Tian X, Wilson LS, Ahmad F, Chen SRW, Movsesian MA, Manganiello V, Maurice DH, Conti M, Backx PH. Phosphodiesterase 4D regulates baseline sarcoplasmic reticulum Ca2+ release and cardiac contractility, independently of L-type Ca2+ current. Circ Res 2011; 109:1024-1030. [PMID: 21903937 DOI: 10.1161/circresaha.111.250464] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
RATIONALE Baseline contractility of mouse hearts is modulated in a phosphatidylinositol 3-kinase-γ-dependent manner by type 4 phosphodiesterases (PDE4), which regulate cAMP levels within microdomains containing the sarcoplasmic reticulum (SR) calcium ATPase type 2a (SERCA2a). OBJECTIVE The goal of this study was to determine whether PDE4D regulates basal cardiac contractility. METHODS AND RESULTS At 10 to 12 weeks of age, baseline cardiac contractility in PDE4D-deficient (PDE4D(-/-)) mice was elevated mice in vivo and in Langendorff perfused hearts, whereas isolated PDE4D(-/-) cardiomyocytes showed increased whole-cell Ca2+ transient amplitudes and SR Ca2+content but unchanged L-type calcium current, compared with littermate controls (WT). The protein kinase A inhibitor R(p)-adenosine-3',5' cyclic monophosphorothioate (R(p)-cAMP) lowered whole-cell Ca2+ transient amplitudes and SR Ca2+ content in PDE4D(-/-) cardiomyocytes to WT levels. The PDE4 inhibitor rolipram had no effect on cardiac contractility, whole-cell Ca2+ transients, or SR Ca2+ content in PDE4D(-/-) preparations but increased these parameters in WT myocardium to levels indistinguishable from those in PDE4D(-/-). The functional changes in PDE4D(-/-) myocardium were associated with increased PLN phosphorylation but not cardiac ryanodine receptor phosphorylation. Rolipram increased PLN phosphorylation in WT cardiomyocytes to levels indistinguishable from those in PDE4D(-/-) cardiomyocytes. In murine and failing human hearts, PDE4D coimmunoprecipitated with SERCA2a but not with cardiac ryanodine receptor. CONCLUSIONS PDE4D regulates basal cAMP levels in SR microdomains containing SERCA2a-PLN, but not L-type Ca2+ channels or ryanodine receptor. Because whole-cell Ca2+ transient amplitudes are reduced in failing human myocardium, these observations may have therapeutic implications for patients with heart failure.
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Zhou Q, Xiao J, Jiang D, Wang R, Vembaiyan K, Wang A, Smith CD, Xie C, Chen W, Zhang J, Tian X, Jones PP, Zhong X, Guo A, Chen H, Zhang L, Zhu W, Yang D, Li X, Chen J, Gillis AM, Duff HJ, Cheng H, Feldman AM, Song LS, Fill M, Back TG, Chen SRW. Carvedilol and its new analogs suppress arrhythmogenic store overload-induced Ca2+ release. Nat Med 2011; 17:1003-9. [PMID: 21743453 DOI: 10.1038/nm.2406] [Citation(s) in RCA: 185] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 05/23/2011] [Indexed: 12/31/2022]
Abstract
Carvedilol is one of the most effective beta blockers for preventing ventricular tachyarrhythmias in heart failure, but the mechanisms underlying its favorable antiarrhythmic benefits remain unclear. Spontaneous Ca(2+) waves, also called store overload-induced Ca(2+) release (SOICR), evoke ventricular tachyarrhythmias in individuals with heart failure. Here we show that carvedilol is the only beta blocker tested that effectively suppresses SOICR by directly reducing the open duration of the cardiac ryanodine receptor (RyR2). This unique anti-SOICR activity of carvedilol, combined with its beta-blocking activity, probably contributes to its favorable antiarrhythmic effect. To enable optimal titration of carvedilol's actions as a beta blocker and as a suppressor of SOICR separately, we developed a new SOICR-inhibiting, minimally beta-blocking carvedilol analog, VK-II-86. VK-II-86 prevented stress-induced ventricular tachyarrhythmias in RyR2-mutant mice and did so more effectively when combined with either of the selective beta blockers metoprolol or bisoprolol. Combining SOICR inhibition with optimal beta blockade has the potential to provide antiarrhythmic therapy that can be tailored to individual patients.
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Tian X, Zhang X, Zeng S, Xu Y, Yao Y, Chen Y, Huang L, Zhao Y, Zhang S. Process Analysis and Multi-Objective Optimization of Ionic Liquid-Containing Acetonitrile Process to Produce 1,3-Butadiene. Chem Eng Technol 2011. [DOI: 10.1002/ceat.201000426] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Cherkasova E, Malinzak E, Rao S, Takahashi Y, Senchenko VN, Kudryavtseva AV, Nickerson ML, Merino M, Hong JA, Schrump DS, Srinivasan R, Linehan WM, Tian X, Lerman MI, Childs RW. Inactivation of the von Hippel-Lindau tumor suppressor leads to selective expression of a human endogenous retrovirus in kidney cancer. Oncogene 2011; 30:4697-706. [PMID: 21602888 PMCID: PMC3161150 DOI: 10.1038/onc.2011.179] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A human endogenous retrovirus type E was recently found to be selectively expressed in most renal cell carcinomas (RCC). Importantly, antigens derived from this provirus are immunogenic, stimulating cytotoxic T-cells that kill RCC cells in vitro and in vivo. Here we show HERV-E expression is restricted to the clear cell subtype of RCC (ccRCC) characterized by an inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene with subsequent stabilization of hypoxia-inducible transcription factors HIF-1α and -2α. HERV-E expression in ccRCC linearly correlated with HIF-2α levels and could be silenced in tumor cells by either transfection of normal VHL or siRNA inhibition of HIF-2α. Using chromatin immunoprecipitation, we demonstrated that HIF-2α can serve as transcriptional factor for HERV-E by binding with HIF response elements (HRE) localized in the proviral 5′LTR. Remarkably, the LTR was found to be hypomethylated only in HERV-E-expressing ccRCC while other tumors and normal tissues possessed a hypermethylated LTR preventing proviral expression. Taken altogether, these findings provide the first evidence that inactivation of a tumor suppressor gene can result in aberrant proviral expression in a human tumor and give insights needed for translational research aimed at boosting human immunity against antigenic components of this HERV-E.
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190
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Kojonazarov B, Sydykov A, Luitel H, Kosanovic D, Pullamsetti S, Tian X, Evans S, Phillips P, Davie N, Weissmann N, Grimminger F, Seeger W, Ghofrani HA, Schermuly RT. Effects of multi-kinase inhibitors on pulmonary vascular and right ventricular remodelling. Pneumologie 2011. [DOI: 10.1055/s-0031-1272117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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191
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Wang R, Zhong X, Meng X, Koop A, Tian X, Jones PP, Fruen BR, Wagenknecht T, Liu Z, Chen SRW. Localization of the dantrolene-binding sequence near the FK506-binding protein-binding site in the three-dimensional structure of the ryanodine receptor. J Biol Chem 2011; 286:12202-12. [PMID: 21262961 DOI: 10.1074/jbc.m110.194316] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dantrolene is believed to stabilize interdomain interactions between the NH2-terminal and central regions of ryanodine receptors by binding to the NH2-terminal residues 590-609 in skeletal ryanodine receptor (RyR1) and residues 601-620 in cardiac ryanodine receptor (RyR2). To gain further insight into the structural basis of dantrolene action, we have attempted to localize the dantrolene-binding sequence in RyR1/RyR2 by using GFP as a structural marker and three-dimensional cryo-EM. We inserted GFP into RyR2 after residues Arg-626 and Tyr-846 to generate GFP-RyR2 fusion proteins, RyR2Arg-626-GFP and RyR2Tyr-846-GFP. Insertion of GFP after residue Arg-626 abolished the binding of a bulky GST- or cyan fluorescent protein-tagged FKBP12.6 but not the binding of a smaller, nontagged FKBP12.6, suggesting that residue Arg-626 and the dantrolene-binding sequence are located near the FKBP12.6-binding site. Using cryo-EM, we have mapped the three-dimensional location of Tyr-846-GFP to domain 9, which is also adjacent to the FKBP12.6-binding site. To further map the three-dimensional location of the dantrolene-binding sequence, we generated 10 FRET pairs based on four known three-dimensional locations (FKBP12.6, Ser-437-GFP, Tyr-846-GFP, and Ser-2367-GFP). Based on the FRET efficiencies of these FRET pairs and the corresponding distance relationships, we mapped the three-dimensional location of Arg-626-GFP or -cyan fluorescent protein, hence the dantrolene-binding sequence, to domain 9 near the FKBP12.6-binding site but distant to the central region around residue Ser-2367. An allosteric mechanism by which dantrolene stabilizes interdomain interactions between the NH2-terminal and central regions is proposed.
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192
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Shen M, Zeng X, Tian X, Zhang F, Zeng X, Zhang X, Xu W. Diffuse alveolar hemorrhage in systemic lupus erythematosus: a retrospective study in China. Lupus 2010; 19:1326-30. [PMID: 20647253 DOI: 10.1177/0961203310373106] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The objective of this study was to determine the clinical features of systemic lupus erythematosus (SLE) patients with diffuse alveolar hemorrhage (DAH). The medical records of 29 patients with DAH among 2133 SLE patients admitted to Peking Union Medical College Hospital from January 2004 to January 2009 were reviewed in this retrospective study. It was found that hypoxemia (100%), dyspnea (90%), cough (79%) and fever (72%), rather than hemoptysis (66%), were the most common symptoms. The most common extrapulmonary presentation was renal involvement (90%). In about 60% of patients nosocomial infection was also present. The mean drop in hemoglobin was 32 ± 10.9 g/l. Mean Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) was 17 ± 9. All patients received high-dose corticosteroid therapy and most were also given immunosuppressive agents. Rates of concomitant nosocomial infection and mechanical ventilation in non-survivors were higher than those of survivors (p < 0.05). DAH is a rare and catastrophic event in SLE. DAH can occur at any stage of the disease course; it usually occurs in patients with active SLE, and is frequently complicated by lupus nephritis. Some patients may have no hemoptysis. Early aggressive management with high-dose steroids and cyclophosphamide is advocated.
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193
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Liu Z, Wang R, Tian X, Zhong X, Gangopadhyay J, Cole R, Ikemoto N, Chen SRW, Wagenknecht T. Dynamic, inter-subunit interactions between the N-terminal and central mutation regions of cardiac ryanodine receptor. J Cell Sci 2010; 123:1775-84. [PMID: 20427316 PMCID: PMC2864716 DOI: 10.1242/jcs.064071] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2010] [Indexed: 11/20/2022] Open
Abstract
Naturally occurring mutations in the cardiac ryanodine receptor (RyR2) have been linked to certain types of cardiac arrhythmias and sudden death. Two mutation hotspots that lie in the N-terminal and central regions of RyR2 are predicted to interact with one another and to form an important channel regulator switch. To monitor the conformational dynamics involving these regions, we generated a fluorescence resonance energy transfer (FRET) pair. A yellow fluorescent protein (YFP) was inserted into RyR2 after residue Ser437 in the N-terminal region, and a cyan fluorescent protein (CFP) was inserted after residue Ser2367 in the central region, to form a dual YFP- and CFP-labeled RyR2 (RyR2(S437-YFP/S2367-CFP)). We transfected HEK293 cells with RyR2(S437-YFP/S2367-CFP) cDNAs, and then examined them by using confocal microscopy and by measuring the FRET signal in live cells. The FRET signals are influenced by modulators of RyR2, by domain peptides that mimic the effects of disease causing RyR2 mutations, and by various drugs. Importantly, FRET signals were also readily detected in cells co-transfected with single CFP (RyR2(S437-YFP)) and single YFP (RyR2(S2367-CFP)) labeled RyR2, indicating that the interaction between the N-terminal and central mutation regions is an inter-subunit interaction. Our studies demonstrate that FRET analyses of this CFP- and YFP-labeled RyR2 can be used not only for investigating the conformational dynamics associated with RyR2 channel gating, but potentially, also for identifying drugs that are capable of stabilizing the conformations of RyR2.
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194
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Tian X, Halfhill AN, Diaz FJ. Localization of phosphorylated SMAD proteins in granulosa cells, oocytes and oviduct of female mice. Gene Expr Patterns 2010; 10:105-12. [PMID: 20176141 DOI: 10.1016/j.gep.2010.02.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 02/09/2010] [Accepted: 02/17/2010] [Indexed: 11/24/2022]
Abstract
SMAD signaling is essential for follicular development. The distribution of activated (phosphorylated) SMADs during folliculogenesis has not been described in detail. The present results indicate that oocytes from preantral and antral follicles contain the mRNA for the receptor regulated Smads (-1, -2, -3, -5 and -9), Smad4 (co-SMAD), and Smad6 and Smad7 (inhibitory SMADs). Levels of Smad5, Smad6 and Smad7 mRNA decreased in fully-grown oocytes compared to growing oocytes. Immunostaining for pSMAD1/5/9, pSMAD2 and pSMAD3 was evident in oocytes from primordial, primary, secondary and antral follicles. We also observed substantial staining for pSMADs in intact fully-grown oocytes from antral follicles. In granulosa cells, immunostaining for both pSMAD2/3 and pSMAD1/5/9 was apparent in preantral granulosa cells from primordial to secondary follicles. In antral follicles, immunostaining for pSMADs became more intense in the cumulus cells surrounding the oocyte. Immunostaining for pSMAD2 and pSMAD1/5/9 was also apparent in the epithelium lining of the oviduct. Clearly, oocytes, preantral granulosa cells, cumulus cells and the epithelium of the oviduct are major targets of SMAD-mediated pathways in female reproductive tissues. The finding that pSMAD pathways are active in oocytes raises new questions regarding the role of TGF-beta superfamily members in directly promoting oocyte development. The extent to which defects in pSMAD signaling in oocytes or the oviduct contribute to infertility in humans or animals remains an open question.
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195
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Wang T, Picard JC, Tian X, Darmency H. A herbicide-resistant ACCase 1781 Setaria mutant shows higher fitness than wild type. Heredity (Edinb) 2010; 105:394-400. [PMID: 20087387 DOI: 10.1038/hdy.2009.183] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
It is often alleged that mutations conferring herbicide resistance have a negative impact on plant fitness. A mutant ACCase1781 allele endowing resistance to the sethoxydim herbicide was introgressed from a resistant green foxtail (Setaria viridis (L.) Beauv) population into foxtail millet (S. italica (L.) Beauv.). (1) Better and earlier growth of resistant plants was observed in a greenhouse cabinet. (2) Resistant plants of the advanced BC7 backcross generation showed more vigorous juvenile growth in the field, earlier flowering, more tillers and higher numbers of grains than susceptible plants did, especially when both genotypes were grown in mixture, but their seeds were lighter than susceptible seeds. (3) Field populations originating from segregating hybrids had the expected allele frequencies under normal growth conditions, but showed a genotype shift toward an excess of homozygous resistant plants within 3 years in stressful conditions. Lower seed size, lower germination rate and perhaps unexplored differences in seed longevity and predation could explain how the resistant plants have the same field fitness over the whole life cycle as the susceptible ones although they produce more seeds. More rapid growth kinetics probably accounted for higher fitness of the resistant plants in adverse conditions. The likelihood of a linkage with a beneficial gene is discussed versus the hypothesis of a pleiotropic effect of the ACCase resistance allele. It is suggested that autogamous species like Setaria could not develop a resistant population without the help of a linkage with a gene producing a higher fitness.
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196
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Tian X, Tang Y, Wang R, Chen W, Chen SW. Molecular Determinants of Ca2+ Release Termination in the Cardiac Ryanodine Receptor. Biophys J 2010. [DOI: 10.1016/j.bpj.2009.12.1638] [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] Open
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197
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Wang Q, Su M, Zhu W, Li X, Jia Y, Guo P, Chen Z, Jiang W, Tian X. Growth inhibition of Microcystis aeruginosa by white-rot fungus Lopharia spadicea. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2010; 62:317-323. [PMID: 20651435 DOI: 10.2166/wst.2010.214] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Harmful cyanobacterial blooms cause water deterioration and threaten human health. It is necessary to remove harmful cyanobacteria with useful methods. A bio-treatment may be one of the best ways to do this. A strain of specific white-rot fungus, Lopharia spadicea, with algicidal ability was isolated. Its algicidal ability on algae under various conditions was determined using three main influence factors: initial chlorophyll-a content, initial pH, and algal cell mixture. The result showed that the chlorophyll-a content of Microcystis aeruginosa FACHB-912, Oocystis borgei FACHB-1108, and Microcystis flos-aquae FACHB-1028 decreased from 798+/-13, 756+/-40, and 773+/-24 microg/L to 0 within 39 h. L. spadicea could also remove more than 95% chlorophyll-a when initial chlorophyll-a content increased from 397+/-13 to 2,132+/-4 microg/L. Moreover, the strain has great removal ability under a broad initial pH range of 5.5 to 9.5. The chlorophyll-a content of the three algal strain mixtures decreased from about 672+/-23 microg/L to 0 within 45 h. After superoxide dismutase (SOD) and malondialdehyde (MAD) were assessed in a co-culture of L. spadicea, it was observed that an increase in MAD content was correlated with the decrease in chlorophyll-a content of M. aeruginosa FACHB-912. This result suggested that the algae was not only greatly inhibited but also severely damaged by the fungus.
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198
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Guo LM, Zhou HY, Xu JW, Wang GS, Tian X, Wang Y, Qiu YM, Jiang JY. Dural arteriovenous fistula at the foramen magnum presenting with subarachnoid hemorrhage: case reports and literature review. Eur J Neurol 2009; 17:684-91. [DOI: 10.1111/j.1468-1331.2009.02895.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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199
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Lü D, Cao X, Tang S, Tian X. Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes. ACTA ACUST UNITED AC 2009; 43:387-94. [PMID: 18726342 DOI: 10.1007/bf02879303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/1999] [Indexed: 11/26/2022]
Abstract
Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of transgenic plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.
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200
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Xu D, Tian X, Zhang W, Zhang X, Liu B, Zhang F. Sjögren's syndrome-onset lupus patients have distinctive clinical manifestations and benign prognosis: A case—control study. Lupus 2009; 19:197-200. [PMID: 19900977 DOI: 10.1177/0961203309348235] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The objective of this study was to investigate the clinical characteristics and prognosis of Sjögren’s syndrome-onset systemic lupus erythematosus (SS/SLE) patients. Medical charts of 41 consecutive SS/SLE inpatients admitted to Peking Union Medical College Hospital (PUMCH) from February 1998 to February 2008 were systematically reviewed, including demographic data, clinical features, laboratory findings, treatment as well as outcomes. Two hundred and fourteen cases were randomly selected as controls from 2331 SLE-only inpatients treated in PUMCH at the same time period. There were significant differences between SS/SLE and SLE-only patients in the following manifestations (p < 0.05): (1) sex ratio (F/M) (41/0 versus 184/30), age (42.8 ± 41.0 years versus 31.8 ± 31.0 years), disease duration (113.8 ± 84.0 months versus 44.9 ± 18.0 months); (2) clinical features, xerostomia (85.4% versus 6.1%), xerophthalmia (75.6% versus 2.3%), renal tubular acidosis (21.9% versus 0%), interstitial lung disease (12.2% versus 2.8%), facial rash (9.8% versus 46.3%), nephrotic syndrome (7.3% versus 31.3%), central nervous system involvement (4.9% versus 19.6%); (3) laboratory findings, ESR (64.6±75.0mm/h versus 46.5±34.0mm/h), C4 (14.8 ± 12.2 g/dl versus 12.0 ± 10.9 g/dl), IgG elevation (56.4% versus 29.9%) and IgA elevation (38.5% versus 20.4%), RF, anti-SSA and anti-SSB positive rates (70.8% versus 20.3%, 82.9% versus 43.4% and 39.0% versus 7.9%); (4) SLEDAI score (8.0 ± 8.0 versus 10.2 ± 10.0), glucocorticoid treatment (methylprednisolone bolus/1—2 mg kg-1 day-1 prednisone/<1 mg kg-1 day-1 prednisone) (8/26/7 versus 91/102/21), and importantly, rate of death and/or severe irreversible organ failure (2.4% versus 14.9%). SS/SLE patients were followed up for 33.0 ± 34.0 months, 40 cases remained stable at a low dose of corticosteroid. In conclusion, different from SLE-only patients, SS/SLE patients have distinctive clinical manifestations and benign prognosis that require less vigorous treatment with glucocorticoids and/or immunosuppressants. Lupus (2010) 19, 197—200.
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