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Tong X, Wang X, Wang C, Li L. Elevated levels of serum MiR-152 and miR-24 in uterine sarcoma: potential for inducing autophagy via SIRT1 and deacetylated LC3. Br J Biomed Sci 2017; 75:7-12. [PMID: 28929922 DOI: 10.1080/09674845.2017.1340225] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND MiRNAs may be associated with the risk of uterine sarcoma and related molecular mechanism remains unclear. METHODS A total of 101 patients with uterine sarcoma (cases) and 54 healthy subjects (controls) were enrolled. The levels of serum miR-152, miR-205, miR-222, miR-24, miR-150 and sirtuin 1 (SIRT1, an NAD +-dependent class III histone deacetylase) were measured by qRT-PCR. HeLa cells were transfected with the mimics of miR-152 and miR-24. The autophagic rates, and the levels of SIRT1 and acetylation of microtubule-associated protein 1A/1B-light chain 3 (LC3) were measured. RESULTS Levels of miR-152, miR-24 and SIRT1 decreased while the levels of miR-205, miR-222 and miR-150 increased in cases vs. controls (all P < 0.05). All miRNAs were linked with stage of the cases' sarcoma (all P = 0.001). Kaplan-Meier analysis demonstrated uterine sarcoma patients have better survival rates with high-level miR-152 and miR-24, with a five-year overall survival of 21.8% and 67.5%, respectively (P = 0.003 and 0.004). The mimics of miR-152 and miR-24 induced autophagy by increasing the level of SIRT1, which deacetylated LC3. CONCLUSION Present findings demonstrate altered miRNA species in uterine sarcoma that are linked to disease stage, and a new molecular mechanism, by which miR-152 and miR-24 promote autophagy by activating SIRT1 and deacetylating LC3.
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Dhiman I, Ziesche R, Wang T, Bilheux H, Santodonato L, Tong X, Jiang CY, Manke I, Treimer W, Chatterji T, Kardjilov N. Setup for polarized neutron imaging using in situ 3He cells at the Oak Ridge National Laboratory High Flux Isotope Reactor CG-1D beamline. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:095103. [PMID: 28964173 DOI: 10.1063/1.5001525] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 08/24/2017] [Indexed: 06/07/2023]
Abstract
In the present study, we report a new setup for polarized neutron imaging at the ORNL High Flux Isotope Reactor CG-1D beamline using an in situ 3He polarizer and analyzer. This development is very important for extending the capabilities of the imaging instrument at ORNL providing a polarized beam with a large field-of-view, which can be further used in combination with optical devices like Wolter optics, focusing guides, or other lenses for the development of microscope arrangement. Such a setup can be of advantage for the existing and future imaging beamlines at the pulsed neutron sources. The first proof-of-concept experiment is performed to study the ferromagnetic phase transition in the Fe3Pt sample. We also demonstrate that the polychromatic neutron beam in combination with in situ 3He cells can be used as the initial step for the rapid measurement and qualitative analysis of radiographs.
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Jonasch E, Fuller G, McCutcheon I, Ding Z, Zhou L, Liu X, Kong W, Powell R, Park IY, Tannir N, Rathmell W, Dong B, Matin S, Tong X, Huang Y, Tong P, Wang J, Walker C, Sun M. The role of hepatocyte nuclear factor 1 homeobox B (HNF1B) loss in chromophobe RCC (ChRCC) development. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx391.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Tong X, Gupta A, Gromala D, Shaw C, Neustaedter C, Choo A. Utilizing Gamification Approaches in Pervasive Health: How Can We Motivate Physical Activity Effectively? EAI ENDORSED TRANSACTIONS ON PERVASIVE HEALTH AND TECHNOLOGY 2017. [DOI: 10.4108/eai.18-7-2017.152897] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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155
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He S, Tong X, Dai F. Multiple genes in the conservative color-patterning region of Lepidoptera are responsible for a melanism mutant (sml) in Silkworm, Bombyx mori. Mech Dev 2017. [DOI: 10.1016/j.mod.2017.04.271] [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]
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156
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Tong X, He S. The Hox genes and body plan of silkworm, Bombyx mori. Mech Dev 2017. [DOI: 10.1016/j.mod.2017.04.197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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157
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Ou Q, Wu X, Bao H, Tong X, Wang X, Zhang X, Chang Z, Mao Y, Shao Y, Zhou C. Investigating novel resistance mechanisms to third generation EGFR TKI osimertinib in non-small cell lung cancer patients using next generation sequencing. J Clin Oncol 2017. [DOI: 10.1200/jco.2017.35.15_suppl.2572] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
2572 Background: Third generation epithelial growth factor receptor ( EGFR) tyrosine kinase inhibitor (TKI) osimertinib (AZD9291) has proven effective in Non-small cell lung cancer (NSCLC) patients who have developed EGFR T790M-mediated resistance to other EGFR TKIs. Unfortunately, a majority of patients still undergo progressed disease after receiving osimertinib treatment. Acquired EGFR C797S mutation has been identified as one major mechanism; however, resistance mechanisms of remaining cases are still largely unknown. Methods: Using next generation sequencing (NGS) targeting 416 cancer-relevant genes, we analyzed the mutation profiles of 99 NSCLC patients that were clinically resistant to osimertinib. Results: In addition to the notable EGFR C797 variants (22%), L792 mutations were identified in 10% of patients, and a further 7% cases carry L718 mutations. Further analysis of 14 patients with paired pre-treatment samples confirmed that these EGFR mutations were acquired during treatment. Interestingly, all L792 mutations are in cis with T790M and in trans with C797 mutations (when present in the same patient). 2 out of 10 L792-positive patients and 6 out of 7 L718-positive patients did not have co-existing C797 mutations, suggesting C797-, L792- and L718-mutated cells may represent different resistant clones. In vitro experiments demonstrated that L792 and L718 mutants also increase osimertinib IC50, and therefore confer their resistance. Besides secondary EGFR mutations, alterations in other key genes such as MET, KRAS, ERBB2 and PIK3CA may also contribute to osimertinib resistance. Notably, MET and KRAS amplifications are present only in patients without above EGFR secondary mutations. Conclusions: In this study, we identified secondary mutations on C797, L792 or L718 residues of EGFR in 29% of osimertinib-resistant patients. Combined with in vitro study, our data strongly suggest that L792 and L718 mutations are likely to alternatively cause osimertinib resistance. Furthermore, MET and KRAS amplification may serve as bypass resistance mechanisms in patients who are EGFR C797-, L792- and L718-wild type.
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Huang YD, Tong X, Chen Q, Xia SW, Zhuo Y, Kang ZH, Xue XY. Mechanism of pingyangmycin-induced apoptosis of cultured human umbilical vein endothelial cells. GENETICS AND MOLECULAR RESEARCH 2017; 16:gmr-16-02-gmr.16029298. [PMID: 28510249 DOI: 10.4238/gmr16029298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In this study, we investigated the effects of pingyangmycin (PYM) on the growth inhibition and apoptosis of human umbilical vein endothelial cells (HUVEC). In this study, we aimed to explore the optimal concentration of PYM to induce the apoptosis of HUVEC and to determine its mechanism of action. After treatment of HUVEC with different concentrations of PYM for 24 h, cell counting kit-8 (CCK-8) was used to detect growth inhibiting effects. Annexin V-FITC/propidium iodide stain was used to detect apoptosis, and western blot was used to detect the expression of glucose-related protein 78 (GPR78) and C/EBP homologous protein (CHOP) endoplasmic reticulum stress proteins. With increasing PYM concentration, the growth inhibition of HUVEC increased (P < 0.05), the apoptotic numbers of HUVEC increased (P < 0.05), with higher PYM concentrations inducing necrosis, and the protein expression of GRP78 and CHOP increased (P < 0.05). PYM could obviously inhibit the proliferation and promote the apoptosis of HUVEC. Necrotic cells were more prevalent than apoptotic cells at high PYM concentrations. This study helped to determine the proper concentration of PYM to induce more apoptosis than necrosis, which is critical to minimize inflammation, enhance the healing of the skin, and maintain safety for the patient. PYM might induce HUVEC apoptosis through the endoplasmic reticulum stress pathway.
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Shu Y, Wu X, Tong X, Wang X, Chang Z, Mao Y, Chen X, Sun J, Wang Z, Hong Z, Zhu L, Zhu C, Chen J, Liang Y, Shao H, Shao YW. Circulating Tumor DNA Mutation Profiling by Targeted Next Generation Sequencing Provides Guidance for Personalized Treatments in Multiple Cancer Types. Sci Rep 2017; 7:583. [PMID: 28373672 PMCID: PMC5428730 DOI: 10.1038/s41598-017-00520-1] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 03/03/2017] [Indexed: 12/12/2022] Open
Abstract
Cancer is a disease of complex genetic alterations, and comprehensive genetic diagnosis is beneficial to match each patient to appropriate therapy. However, acquisition of representative tumor samples is invasive and sometimes impossible. Circulating tumor DNA (ctDNA) is a promising tool to use as a non-invasive biomarker for cancer mutation profiling. Here we implemented targeted next generation sequencing (NGS) with a customized gene panel of 382 cancer-relevant genes on 605 ctDNA samples in multiple cancer types. Overall, tumor-specific mutations were identified in 87% of ctDNA samples, with mutation spectra highly concordant with their matched tumor tissues. 71% of patients had at least one clinically-actionable mutation, 76% of which have suggested drugs approved or in clinical trials. In particular, our study reveals a unique mutation spectrum in Chinese lung cancer patients which could be used to guide treatment decisions and monitor drug-resistant mutations. Taken together, our study demonstrated the feasibility of clinically-useful targeted NGS-based ctDNA mutation profiling to guide treatment decisions in cancer.
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Rhodes D, Chenet DA, Janicek BE, Nyby C, Lin Y, Jin W, Edelberg D, Mannebach E, Finney N, Antony A, Schiros T, Klarr T, Mazzoni A, Chin M, Chiu YC, Zheng W, Zhang QR, Ernst F, Dadap JI, Tong X, Ma J, Lou R, Wang S, Qian T, Ding H, Osgood RM, Paley DW, Lindenberg AM, Huang PY, Pasupathy AN, Dubey M, Hone J, Balicas L. Engineering the Structural and Electronic Phases of MoTe 2 through W Substitution. NANO LETTERS 2017; 17:1616-1622. [PMID: 28145719 DOI: 10.1021/acs.nanolett.6b04814] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
MoTe2 is an exfoliable transition metal dichalcogenide (TMD) that crystallizes in three symmetries: the semiconducting trigonal-prismatic 2H- or α-phase, the semimetallic and monoclinic 1T'- or β-phase, and the semimetallic orthorhombic γ-structure. The 2H-phase displays a band gap of ∼1 eV making it appealing for flexible and transparent optoelectronics. The γ-phase is predicted to possess unique topological properties that might lead to topologically protected nondissipative transport channels. Recently, it was argued that it is possible to locally induce phase-transformations in TMDs, through chemical doping, local heating, or electric-field to achieve ohmic contacts or to induce useful functionalities such as electronic phase-change memory elements. The combination of semiconducting and topological elements based upon the same compound might produce a new generation of high performance, low dissipation optoelectronic elements. Here, we show that it is possible to engineer the phases of MoTe2 through W substitution by unveiling the phase-diagram of the Mo1-xWxTe2 solid solution, which displays a semiconducting to semimetallic transition as a function of x. We find that a small critical W concentration xc ∼ 8% stabilizes the γ-phase at room temperature. This suggests that crystals with x close to xc might be particularly susceptible to phase transformations induced by an external perturbation, for example, an electric field. Photoemission spectroscopy, indicates that the γ-phase possesses a Fermi surface akin to that of WTe2.
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161
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Jiang CY, Tong X, Brown DR, Glavic A, Ambaye H, Goyette R, Hoffmann M, Parizzi AA, Robertson L, Lauter V. New generation high performance in situ polarized 3He system for time-of-flight beam at spallation sources. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:025111. [PMID: 28249509 DOI: 10.1063/1.4975991] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Modern spallation neutron sources generate high intensity neutron beams with a broad wavelength band applied to exploring new nano- and meso-scale materials from a few atomic monolayers thick to complicated prototype device-like systems with multiple buried interfaces. The availability of high performance neutron polarizers and analyzers in neutron scattering experiments is vital for understanding magnetism in systems with novel functionalities. We report the development of a new generation of the in situ polarized 3He neutron polarization analyzer for the Magnetism Reflectometer at the Spallation Neutron Source at Oak Ridge National Laboratory. With a new optical layout and laser system, the 3He polarization reached and maintained 84% as compared to 76% in the first-generation system. The polarization improvement allows achieving the transmission function varying from 50% to 15% for the polarized neutron beam with the wavelength band of 2-9 Angstroms. This achievement brings a new class of experiments with optimal performance in sensitivity to very small magnetic moments in nano systems and opens up the horizon for its applications.
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162
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Chen K, Zhou F, Shen W, Jiang T, Wu X, Tong X, Shao YW, Qin S, Zhou C. Novel Mutations on EGFR Leu792 Potentially Correlate to Acquired Resistance to Osimertinib in Advanced NSCLC. J Thorac Oncol 2017; 12:e65-e68. [PMID: 28093244 DOI: 10.1016/j.jtho.2016.12.024] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 12/18/2016] [Accepted: 12/19/2016] [Indexed: 01/13/2023]
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163
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Wang H, Tong X, Liu M, Hu H, Li Z, Xiang Z, Dai F, Lu C. Fine Mapping of a Degenerated Abdominal Legs Mutant (Edl) in Silkworm, Bombyx mori. PLoS One 2017; 12:e0169224. [PMID: 28081147 PMCID: PMC5231277 DOI: 10.1371/journal.pone.0169224] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 12/13/2016] [Indexed: 12/05/2022] Open
Abstract
In insects, abdominal appendages, also called prolegs, vary due to adaptive evolution. Mutations on prolegs within species provide insights to better understand the mechanisms underlying appendage development and diversity. In silkworm Bombyx mori, extra-crescents and degenerated abdominal legs (Edl) mutant, belonging to the E pseudoallele group, is a spontaneous mutation that adds crescents and degenerates prolegs on the third abdominal segment (A3). This mutation may be a homeotic transformation of A3 to A2. In this study, the Edl locus was mapped within approximately a 211 Kb region that is 10 Kb upstream of Bmabdominal-A (Bmabd-A). RT-quantitative PCR (RT-qPCR) and Western blot analysis of Bmabd-A expression showed a slight but significant decrease, while the expression of BmUltrabithorax (BmUbx) was up-regulated in the Edl mutant compared to wildtype (Dazao). Moreover, we also found that BmDistal-less (BmDll), which regulated the development of distal proleg structures, was missing at the tips of the A3 prolegs in the Edl mutant compared to BmDll expression in normally developed prolegs in both the wildtype and mutant. Collectively, we identified approximately a 211 Kb region in the Edl locus that regulates BmUbx and Bmabd-A expression and found that changes in BmUbx and Bmabd-A expression may lead to the loss of distal proleg structures in B. mori.
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Han MJ, Zhou QZ, Zhang HH, Tong X, Lu C, Zhang Z, Dai F. iMITEdb: the genome-wide landscape of miniature inverted-repeat transposable elements in insects. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2016; 2016:baw148. [PMID: 28025339 PMCID: PMC5199201 DOI: 10.1093/database/baw148] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 09/19/2016] [Accepted: 10/18/2016] [Indexed: 01/23/2023]
Abstract
Miniature inverted-repeat transposable elements (MITEs) have attracted much attention due to their widespread occurrence and high copy numbers in eukaryotic genomes. However, the systematic knowledge about MITEs in insects and other animals is still lacking. In this study, we identified 6012 MITE families from 98 insect species genomes. Comparison of these MITEs with known MITEs in the NCBI non-redundant database and Repbase showed that 5701(∼95%) of 6012 MITE families are novel. The abundance of MITEs varies drastically among different insect species, and significantly correlates with genome size. In general, larger genomes contain more MITEs than small genomes. Furthermore, all identified MITEs were included in a newly constructed database (iMITEdb) (http://gene.cqu.edu.cn/iMITEdb/), which has functions such as browse, search, BLAST and download. Overall, our results not only provide insight on insect MITEs but will also improve assembly and annotation of insect genomes. More importantly, the results presented in this study will promote studies of MITEs function, evolution and application in insects. Database URL: http://gene.cqu.edu.cn/iMITEdb/
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Tong X. Preparation and Electrochemical Performance of Modified LiNi0.5Mn1.5O4Cathode Material for Lithium-ion Batteries. INT J ELECTROCHEM SC 2016. [DOI: 10.20964/2016.09.39] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Fang T, Zhou D, Lu L, Tong X, Wu J, Yi L. LXW7 ameliorates focal cerebral ischemia injury and attenuates inflammatory responses in activated microglia in rats. ACTA ACUST UNITED AC 2016; 49:e5287. [PMID: 27533766 PMCID: PMC4988477 DOI: 10.1590/1414-431x20165287] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 06/15/2016] [Indexed: 02/06/2023]
Abstract
Inflammation plays a pivotal role in ischemic stroke, when activated microglia release excessive pro-inflammatory mediators. The inhibition of integrin αvβ3 improves outcomes in rat focal cerebral ischemia models. However, the mechanisms by which microglia are neuroprotective remain unclear. This study evaluated whether post-ischemic treatment with another integrin αvβ3 inhibitor, the cyclic arginine-glycine-aspartic acid (RGD) peptide-cGRGDdvc (LXW7), alleviates cerebral ischemic injury. The anti-inflammatory effect of LXW7 in activated microglia within rat focal cerebral ischemia models was examined. A total of 108 Sprague-Dawley rats (250–280 g) were subjected to middle cerebral artery occlusion (MCAO). After 2 h, the rats were given an intravenous injection of LXW7 (100 μg/kg) or phosphate-buffered saline (PBS). Neurological scores, infarct volumes, brain water content (BWC) and histology alterations were determined. The expressions of pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β)], and Iba1-positive activated microglia, within peri-ischemic brain tissue, were assessed with ELISA, western blot and immunofluorescence staining. Infarct volumes and BWC were significantly lower in LXW7-treated rats compared to those in the MCAO + PBS (control) group. The LXW7 treatment lowered the expression of pro-inflammatory cytokines. There was a reduction of Iba1-positive activated microglia, and the TNF-α and IL-1β expressions were attenuated. However, there was no difference in the Zea Longa scores between the ischemia and LXW7 groups. The results suggest that LXW7 protected against focal cerebral ischemia and attenuated inflammation in activated microglia. LXW7 may be neuroprotective during acute MCAO-induced brain damage and microglia-related neurodegenerative diseases.
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Shao Y, Tong X, Wang X, Chang Z, Mao Y, Wu X. Circulating tumor DNA mutational profiling by targeted next generation sequencing guides personalized treatments in multiple cancer types. J Clin Oncol 2016. [DOI: 10.1200/jco.2016.34.15_suppl.1581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Yan ZP, Tong X, Liu ST, Ma Y, Peng SF, Yang X, Fan H. Role and diagnostic value of gene variants in assessing the risk of chronic obstructive pulmonary disease. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr7854. [PMID: 27323020 DOI: 10.4238/gmr.15027854] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Meta-analyses have revealed many positive associations between gene variants and susceptibility to chronic obstructive pulmonary disease (COPD). However, some of those positive results may be false positives. Therefore, we investigated the genetic polymorphisms associated with COPD risk and determined their diagnostic value. We extracted the odds ratio (OR) and 95% confidence interval for each polymorphism from published meta-analyses concerning gene variants and COPD susceptibility in October 2014, subsequently we calculated false-positive report probabilities (FPRPs) for statistically significant associations (P value < 0.05). We determined the diagnostic value of the true positive polymorphisms of COPD using the Meta-DiSc software. Twenty-five gene polymorphisms were significantly associated with COPD risk. The FPRP test results were as follows: 1) when the prior probability was 0.001 and the OR was 1.5, ADAM33 rs612709, CHRNA3/5 rs1051730, CHRNA3/5 rs8034191, CHRNA3/5 rs16969968, and TGFB1 rs1800470 were truly associated with COPD risk (FPRP < 0.2); 2) when the prior probability was 0.000001 and the OR was 1.5, all the variants except TGFB1 rs1800470 remained noteworthy; and 3) when the probability was 0.000001 and the OR was 1.2, ADAM33 rs612709 and CHRNA3/5 rs1051730 remained true positives. Unfortunately, the results of the diagnostic accuracy meta-analyses suggested that none of the variants had high value for COPD diagnosis.
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He S, Tong X, Lu K, Lu Y, Luo J, Yang W, Chen M, Han MJ, Hu H, Lu C, Dai F. Comparative Analysis of Transcriptomes among Bombyx mori Strains and Sexes Reveals the Genes Regulating Melanic Morph and the Related Phenotypes. PLoS One 2016; 11:e0155061. [PMID: 27153103 PMCID: PMC4859508 DOI: 10.1371/journal.pone.0155061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 04/23/2016] [Indexed: 11/19/2022] Open
Abstract
As a source of insect polymorphism, melanism plays an important role in ecological adaption and usually endows advantageous phenotypic-effects on insects. However, due to the mechanistic diversity, there are knowledge gaps in the molecular mechanisms underlying melanism and the related phenotypes. In silk moths, a recessive melanic mutant (sex-controlled melanism, sml) strain exhibits extended adult longevity. We took a transcriptome approach to perform a comparative analysis between this sml strain and a wild-type strain (Dazao). Our analysis resulted in the identification of 59 unique differentially expressed genes in the melanic mutant. Two key genes (laccase2 and yellow) involved in melanin formation were significantly up-regulated in melanic individuals. The laccase2 B-type isoform (BGIBMGA006746) was found to likely participate in the silkworm cuticular melanism process at late pupal stage. Moreover, we discovered 22 cuticular protein encoding genes with the possible function in melanin transport and/or maintenance. Based on our findings, we presume that the longer survival of the melanic sml male moths might be associated with the enhanced antioxidant defense systems and a reduction in the insulin/IGF-1 signaling pathway (IIS). These findings will facilitate the understanding of the molecular basis underlying melanism and the derived phenotypic-effects.
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Epson EE, Cronquist A, Lamba K, Kimura AC, Hassan R, Selvage D, McNeil CS, Varan AK, Silvaggio JL, Fan L, Tong X, Spradling PR. Risk factors for hospitalisation and associated costs among patients with hepatitis A associated with imported pomegranate arils, United States, 2013. Public Health 2016; 136:144-51. [PMID: 27156991 DOI: 10.1016/j.puhe.2016.03.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 03/22/2016] [Accepted: 03/25/2016] [Indexed: 01/10/2023]
Abstract
OBJECTIVES To assess hospitalisation risk factors and economic effects associated with a multistate hepatitis A outbreak in 2013. STUDY DESIGN Retrospective case series. METHODS Eligible outbreak-related cases confirmed by September 1, 2013, were defined as acute hepatitis symptoms and positive IgM anti-hepatitis A during March 15-August 12 among patients who consumed the food vehicle or had the outbreak genotype. We reviewed medical records, comparing demographic and clinical characteristics among hospitalized and non-hospitalized patients; we used logistic regression analysis to identify factors associated with hospitalization. We interviewed patients regarding symptom duration and healthcare usage and estimated per-patient and total costs. Health departments reported outbreak-related personnel hours. RESULTS Medical records were reviewed for 147/159 (92%) eligible patients; median age was 48 (range: 1-84) years, and 64 (44%) patients were hospitalized. Having any chronic medical condition was independently associated with hospitalisation (odds ratio, 3.80; 95% confidence interval, 1.68-8.62). Interviews were completed for 114 (72%) eligible patients; estimated per-patient cost of healthcare and productivity loss was $13,467 for hospitalized and $2138 for non-hospitalized patients and $1,304,648 for all 165 outbreak-related cases. State and local public health personnel expenditures included 82 h and $3221/outbreak-related case. CONCLUSIONS Hospitalisations in this outbreak were associated with chronic medical conditions and resulted in substantial healthcare usage and lost productivity. These data can be used to inform future evaluation of expansion of hepatitis A vaccination recommendations to include adults with chronic medical conditions.
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Sims EK, Lakhter A, Restrepo I, Tong X, Kono T, Anderson-Baucum E, Evans-Molina C. ID: 84: β CELL DERIVED MIR-21 INCREASES APOPTOSIS VIA TRANSLATIONAL INHIBITION OF THE ANTIAPOPTOTIC PROTEIN BCL2 AND COULD SERVE AS A BIOMARKER OF TYPE 1 DIABETES MELLITUS. J Investig Med 2016. [DOI: 10.1136/jim-2016-000120.35] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BackgroundAltered β cell and serum microRNA (miRNA) profiles have been described in Type 1 Diabetes (T1D), suggesting a role for these small, non-coding RNAs in β cell pathophysiology. Whereas previous reports have demonstrated increased expression of β cell miR-21 in models of T1D, the role of miR-21 in the β cell under pro-inflammatory conditions has been controversial.ObjectivesOur goal was to define the effect of miR-21 on β cell survival, through identification of miR-21 regulated gene targets. Furthermore, we sought to identify whether circulating extracellular vesicle (EV) β cell-derived miR-21 may reflect inflammatory stress within the islet during T1D development.Design/MethodsINS-1 828/13 or 828/33 β cells were treated with a cytokine mix to mimic the early T1D milieu. Islets were isolated from NOD mice with autoimmune diabetes and mice treated with multiple low dose streptozotocin (STZ) to induce chemical diabetes. To define the effects of miR-21 overexpression or inhibition, cells were transfected with a miR-21 mimic or inhibitor. In silico prediction tools were used to identify potential miR-21 targets. Luciferase assays and polyribosomal profiling (PRP) were performed to understand miR-21 and target interactions. EV RNA was isolated from media of cytokine treated cells and terminal serum of diabetic and normoglycemic control mice. Serum EV miR-21 concentration was assayed using digital droplet PCR.Resultsβ cell miR-21 was increased in cytokine treated INS-1 cells as well as islets from mouse models of T1D. miR-21 overexpression decreased β cell count and viability, and increased cleaved caspase 3 levels, suggesting increased apoptosis. In silico prediction tools identified the anti-apoptotic mRNA B Cell Lymphoma 2 (BCL2) as a conserved target of miR-21. Consistent with this, miR-21 overexpression decreased BCL2 protein expression. miR-21 inhibition had the opposite effect, increasing BCL2 protein levels and reducing cleaved caspase 3. Luciferase assay revealed decreased activation of the human BCL23' untranslated region (UTR) following miR-21 mimic treatment, suggesting a direct interaction between miR-21 and the BCL2 3'UTR. This effect was absent in cells transfected with a mutated BCL2 3'UTR. Preliminary polyribosomal profiling of cells overexpressing miR-21 revealed a shift of BCL-2 message toward monosomal fractions, indicating inhibition of BCL2 translation. The proapoptotic effect of overexpression was abrogated in 928/33 cells, which constitutively overexpress BCL-2. Cytokine treatment increased miR-21 levels in treated cell media 5-fold. This effect was doubled in EVs isolated from media. Although no increase in serum EVs existed in mice with chemical diabetes induced by STZ, when compared to controls, serum EV miR-21 was more than doubled in NOD mice with autoimmune diabetes.ConclusionsIn contrast to a prosurvival role in other systems, our results demonstrate that miR-21 increases β cell apoptosis, in part, via binding of the BCL2 mRNA 3'UTR to inhibit translation. In addition, our results suggest that cytokine-induced miR-21 production in β cells could increase circulating miR-21 levels during T1D development. Future work will identify new targets of β cell miR-21 and examine its role in vivo using transgenic mouse models, as well as verify elevations of exosomal miR-21 in serum samples from prediabetic mice and humans with developing T1D.
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Zhang JW, Tong X, Wan Z, Wang Y, Qin LQ, Szeto IMY. Effect of whey protein on blood lipid profiles: a meta-analysis of randomized controlled trials. Eur J Clin Nutr 2016; 70:879-85. [PMID: 27026427 DOI: 10.1038/ejcn.2016.39] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 02/12/2016] [Accepted: 02/21/2016] [Indexed: 01/10/2023]
Abstract
Previous studies have suggested that whey supplementation may have beneficial effects on lipid profiles, although results were inconsistent. A literature search was performed in March 2015 for randomized controlled trials observing the effects of whey protein and its derivatives on circulating levels of triacylglycerol (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). A meta-analysis was subsequently conducted. The meta-analysis results of 13 trials showed that whey supplementation significantly reduced the circulating TG level by 0.11 mmol/l (95% CI: -0.21, 0 mmol/l), whereas the whey protein had no effects on circulating TC (-0.11 mmol/l, 95% CI: -0.27, 0.05 mmol/l), LDL-C (-0.08 mmol/l, 95% CI: -0.23, 0.07 mmol/l) and HDL-C (0.01 mmol/l, 95% CI: -0.04, 0.05 mmol/l). Subgroup analysis showed that significant TG reduction disappeared in participants with low body mass index, low supplemental whey dose or under exercise training/energy restriction during the trial. No evidence of heterogeneity across studies and publication bias was observed. In conclusion, our findings demonstrated that the effects of whey protein supplementation were modest, with an overall lowering effect on TG but no effect on TC, LDL-C and HDL-C.
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Yan LL, Wan W, Chen L, Zhou F, Gong SJ, Tong X, Feng M. Exploring structural phase transitions of ion crystals. Sci Rep 2016; 6:21547. [PMID: 26865229 PMCID: PMC4749997 DOI: 10.1038/srep21547] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 01/27/2016] [Indexed: 11/09/2022] Open
Abstract
Phase transitions have been a research focus in many-body physics over past decades. Cold ions, under strong Coulomb repulsion, provide a repealing paradigm of exploring phase transitions in stable confinement by electromagnetic field. We demonstrate various conformations of up to sixteen laser-cooled (40)Ca(+) ion crystals in a home-built surface-electrode trap, where besides the usually mentioned structural phase transition from the linear to the zigzag, two additional phase transitions to more complicated two-dimensional configurations are identified. The experimental observation agrees well with the numerical simulation. Heating due to micromotion of the ions is analysed by comparison of the numerical simulation with the experimental observation. Our investigation implies very rich and complicated many-body behaviour in the trapped-ion systems and provides effective mechanism for further exploring quantum phase transitions and quantum information processing with ultracold trapped ions.
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Chen LM, Liu YQ, Shen JN, Peng YL, Xiong TY, Tong X, Du L, Zhang YG. The 100 top-cited tuberculosis research studies. Int J Tuberc Lung Dis 2016; 19:717-22. [PMID: 25946366 DOI: 10.5588/ijtld.14.0925] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The examination of top-cited studies is a useful method for identify and monitoring outstanding scientific research. The objective of this study was to identify and analyse the characteristics of the top 100 cited research studies on tuberculosis (TB) based on the Web of Knowledge. Overall, the top 100 cited studies were cited between 366 and 4443 times, and were published between 1995 and 2010, with the largest number of publications in 2003 and in 1995. Four studies were attributed to a single author and 10 to two authors; the number of authors exceeded six in 50 studies. Nine authors had more than one study as the first author and 18 authors had more than one study as the corresponding author. The United States contributed the largest number of studies, followed by the United Kingdom and France. The institutions with the largest number of articles were the Institut National de la Santé et de la Recherche Médicale in France and the University of California in the United States. The studies appeared in 35 journals, with 11 published in Science, followed by PNAS and NEJM. The majority of TB articles have been published in those medical journals with the highest impact factors, and are from the most industrialised countries.
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Li F, Zeng M, Li J, Tong X, Xu H. Sb doped Li4Ti5O12 hollow spheres with enhanced lithium storage capability. RSC Adv 2016. [DOI: 10.1039/c6ra01831a] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The Sb doped Li4Ti5O12 hollow spheres with an average diameter of around 3.5 μm were synthesized successfully via through a two-step process. Sb5+ doping can improve the capacity and maintain the cycling stability.
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Tong X, Aoyama H, Sudhakar S, Chen H, Shilton BH, Bai D. The First Extracellular Domain Plays an Important Role in Unitary Channel Conductance of Cx50 Gap Junction Channels. PLoS One 2015; 10:e0143876. [PMID: 26625162 PMCID: PMC4666595 DOI: 10.1371/journal.pone.0143876] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/10/2015] [Indexed: 11/28/2022] Open
Abstract
Gap junction (GJ) channels provide direct passage for ions and small molecules to be exchanged between neighbouring cells and are crucial for many physiological processes. GJ channels can be gated by transjunctional voltage (known as Vj-gating) and display a wide range of unitary channel conductance (γj), yet the domains responsible for Vj-gating and γj are not fully clear. The first extracellular domain (E1) of several connexins has been shown to line part of their GJ channel pore and play important roles in Vj-gating properties and/or ion permeation selectivity. To test roles of the E1 of Cx50 GJ channels, we generated a chimera, Cx50Cx36E1, where the E1 domain of Cx50 was replaced with that of Cx36, a connexin showing quite distinct Vj-gating and γj from those of Cx50. Detailed characterizations of the chimera and three point mutants in E1 revealed that, although the E1 domain is important in determining γj, the E1 domain of Cx36 is able to effectively function within the context of the Cx50 channel with minor changes in Vj-gating properties, indicating that sequence differences between the E1 domains in Cx36 and Cx50 cannot account for their drastic differences in Vj-gating and γj. Our homology models of the chimera and the E1 mutants revealed that electrostatic properties of the pore-lining residues and their contribution to the electric field in the pore are important factors for the rate of ion permeation of Cx50 and possibly other GJ channels.
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Tong X, Spradling PR. Increase in nonhepatic diagnoses among persons with hepatitis C hospitalized for any cause, United States, 2004-2011. J Viral Hepat 2015; 22:906-13. [PMID: 25894392 PMCID: PMC6743325 DOI: 10.1111/jvh.12414] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/01/2015] [Indexed: 01/08/2023]
Abstract
Although persons with hepatitis C virus (HCV) infection may experience nonhepatic illnesses, little is known about the frequency of and trends in such conditions in a population-based sample of HCV-infected persons. Using hospitalization data collected during 2004-2011 from the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project, we examined trends in comorbidities among all hospitalizations that included either a principal or secondary HCV diagnostic code (i.e., HCV was not necessarily the cause for hospitalization). We also compared comorbidities among all persons aged 45-64 years hospitalized with and without principal or secondary HCV diagnostic codes. The estimated number of hospitalizations among persons with HCV infection increased from 850,490 in 2004-2005 to 1,178,633 in 2010-2011; mean age at hospitalization was 50 years in 2004-2005 and 52.5 years in 2010-2011. There were significant increases in the prevalence of most medical and psychiatric comorbidities; the largest were for lipid disorders, chronic kidney disease and obesity. Among HCV-infected aged 45-64 persons hospitalized for any cause, the prevalence of alcohol /substance abuse, mental disorders, chronic kidney disease, pneumonia, hepatitis B virus infection and HIV infection were significantly higher than those aged 45-64 persons hospitalized without HCV infection (P < 0.001 for all). The prevalence of cryoglobulinaemia, vasculitis, nephrotic syndrome or membranoproliferative glomerulonephritis and porphyria cutanea tarda among hospitalizations with HCV infection was consistently low during the study period (i.e., <0.5%). The increase we observed in nonhepatic comorbidities associated with a high risk of HCV-related complications has important implications for the current HCV treatment recommendations in a greatly expanded treatment population.
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Li C, Wang Y, Chen Y, Zhang C, Dong Z, Zhang S, Tong Y, Lv Z, Tong X, Wang J, Zhang P. Optimal blood pressure levels in patients undergoing intravenous thrombolysis for AIS. Minerva Med 2015; 106:255-258. [PMID: 26393383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
AIM We wished to define the most optimal blood pressure ranges in patients with acute ischemic stroke (AIS) undergoing intravenous thrombolysis treatment. METHODS The study comprised 626 patients with AIS who underwent the treatment with recombinant tissue plasminogen activator. The patients were randomly assigned to receive either conservative blood pressure lowering regimen (N.=302, target systolic blood pressure of 151-185 mmHg) or intensive blood pressure lowering regimen (N.=324, target systolic blood pressure of 141-150 mm Hg). The outcomes were occurrence of intracranial hemorrhages and survival after 3 months post-treatment. RESULTS Patients who received intensive blood pressure lowering regimen showed significantly lower rates of intracranial hemorrhage and mortality. Also, these patients demonstrated a trend to better overall condition. CONCLUSION Intensive blood pressure lowering regimen warrants a safe and effective intravenous thrombolysis in patients with AIS, and the targeted systolic blood pressure levels should be within 141-150 mmHg.
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Chen B, Ma R, Ma G, Guo X, Tong X, Tang G, Kang L. Haemocyanin is essential for embryonic development and survival in the migratory locust. INSECT MOLECULAR BIOLOGY 2015; 24:517-527. [PMID: 26010377 DOI: 10.1111/imb.12177] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Haemocyanins are commonly known as copper-containing oxygen carriers within the haemolymph of arthropods, and have been found in many orders of insects. However, it remains unresolved why haemocyanins persist in insects that possess elaborate tracheal systems for oxygen diffusion to cells. Here we identified haemocyanins in the migratory locust Locusta migratoria that consists of two distinct subunits, Hc1 and Hc2. Genomic sequence analysis indicated that Hc1 and Hc2 have four and three gene copies, respectively, which may have evolved via gene duplication followed by divergent evolution of introns. The two subunits exhibit abundant and embryonic-specific expression at the mRNA and protein level; their expression peaks in the mid-term embryo and is not detectable in the late nymphal and adult stages. A larger proportion of the haemocyanins is present in the yolk compared with that in the embryo. Immunostaining shows that haemocyanins in the embryo are mainly expressed in the epidermis. Knockdown of Hc1 and Hc2 results in significant embryonic developmental delay and abnormality as well as reduced egg hatchability, ie the proportion of hatched eggs. These results reveal a previously unappreciated and fundamental role for haemocyanins in embryonic development and survival in insects, probably involving the exchange of molecules (eg O2 ) between the embryo and its environment.
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Wang J, Liu M, Tong X, Peng W, Cao H, Su W. Chromatographic Fingerprint Analysis and Characterization of Constituents in Shenqi Fuzheng Injection by HPLC-DAD-ELSD and UFLC-DAD-Q-TOF Tandem Mass Spectrometry Techniques. ACTA CHROMATOGR 2015. [DOI: 10.1556/achrom.27.2015.3.11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Tong X, He S, Chen J, Hu H, Xiang Z, Lu C, Dai F. A novel laminin β gene BmLanB1-w regulates wing-specific cell adhesion in silkworm, Bombyx mori. Sci Rep 2015. [PMID: 26212529 PMCID: PMC4515764 DOI: 10.1038/srep12562] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Laminins are important basement membrane (BM) components with crucial roles in development. The numbers of laminin isoforms in various organisms are determined by the composition of the different α, β, and γ chains, and their coding genes, which are variable across spieces. In insects, only two α, one β, and one γ chains have been identified thus far. Here, we isolated a novel laminin β gene, BmLanB1-w, by positional cloning of the mutant (crayfish, cf) with blistered wings in silkworm. Gene structure analysis showed that a 2 bp deletion of the BmLanB1-w gene in the cf mutant caused a frame-shift in the open reading frame (ORF) and generated a premature stop codon. Knockdown of the BmLanB1-w gene produced individuals exhibiting blistered wings, indicating that this laminin gene was required for cell adhesion during wing development. We also identified laminin homologs in different species and showed that two copies of β laminin likely originated in Lepidoptera during evolution. Furthermore, phylogenetic and gene expression analyses of silkworm laminin genes revealed that the BmLanB1-w gene is newly evolved, and is required for wing-specific cell adhesion. This is the first report showing the tissue specific distribution and functional differentiation of β laminin in insects.
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Tong X, Kono T, Evans-Molina C. Nitric oxide stress and activation of AMP-activated protein kinase impair β-cell sarcoendoplasmic reticulum calcium ATPase 2b activity and protein stability. Cell Death Dis 2015; 6:e1790. [PMID: 26086963 PMCID: PMC4669835 DOI: 10.1038/cddis.2015.154] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 04/13/2015] [Accepted: 04/20/2015] [Indexed: 11/15/2022]
Abstract
The sarcoendoplasmic reticulum Ca2+ ATPase 2b (SERCA2b) pump maintains a steep Ca2+ concentration gradient between the cytosol and ER lumen in the pancreatic β-cell, and the integrity of this gradient has a central role in regulated insulin production and secretion, maintenance of ER function and β-cell survival. We have previously demonstrated loss of β-cell SERCA2b expression under diabetic conditions. To define the mechanisms underlying this, INS-1 cells and rat islets were treated with the proinflammatory cytokine interleukin-1β (IL-1β) combined with or without cycloheximide or actinomycin D. IL-1β treatment led to increased inducible nitric oxide synthase (iNOS) gene and protein expression, which occurred concurrently with the activation of AMP-activated protein kinase (AMPK). IL-1β led to decreased SERCA2b mRNA and protein expression, whereas time-course experiments revealed a reduction in protein half-life with no change in mRNA stability. Moreover, SERCA2b protein but not mRNA levels were rescued by treatment with the NOS inhibitor l-NMMA (NG-monomethyl l-arginine), whereas the NO donor SNAP (S-nitroso-N-acetyl-d,l-penicillamine) and the AMPK activator AICAR (5-aminoimidazole-4-carboxamide ribonucleotide) recapitulated the effects of IL-1β on SERCA2b protein stability. Similarly, IL-1β-induced reductions in SERCA2b expression were rescued by pharmacological inhibition of AMPK with compound C or by transduction of a dominant-negative form of AMPK, whereas β-cell death was prevented in parallel. Finally, to determine a functional relationship between NO and AMPK signaling and SERCA2b activity, fura-2/AM (fura-2-acetoxymethylester) Ca2+ imaging experiments were performed in INS-1 cells. Consistent with observed changes in SERCA2b expression, IL-1β, SNAP and AICAR increased cytosolic Ca2+ and decreased ER Ca2+ levels, suggesting congruent modulation of SERCA activity under these conditions. In aggregate, these results show that SERCA2b protein stability is decreased under inflammatory conditions through NO- and AMPK-dependent pathways and provide novel insight into pathways leading to altered β-cell calcium homeostasis and reduced β-cell survival in diabetes.
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Dai F, Qiao L, Cao C, Liu X, Tong X, He S, Hu H, Zhang L, Wu S, Tan D, Xiang Z, Lu C. Aspartate Decarboxylase is Required for a Normal Pupa Pigmentation Pattern in the Silkworm, Bombyx mori. Sci Rep 2015; 5:10885. [PMID: 26077025 PMCID: PMC4468592 DOI: 10.1038/srep10885] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 04/07/2015] [Indexed: 12/21/2022] Open
Abstract
The pigmentation pattern of Lepidoptera varies greatly in different development stages. To date, the effects of key genes in the melanin metabolism pathway on larval and adult body color are distinct, yet the effects on pupal pigmentation remains unclear. In the silkworm, Bombyx mori, the black pupa (bp) mutant is only specifically melanized at the pupal stage. Using positional cloning, we found that a mutation in the Aspartate decarboxylase gene (BmADC) is causative in the bp mutant. In the bp mutant, a SINE-like transposon with a length of 493 bp was detected ~2.2 kb upstream of the transcriptional start site of BmADC. This insertion causes a sharp reduction in BmADC transcript levels in bp mutants, leading to deficiency of β-alanine and N-β-alanyl dopamine (NBAD), but accumulation of dopamine. Following injection of β-alanine into bp mutants, the color pattern was reverted that of the wild-type silkworms. Additionally, melanic pupae resulting from knock-down of BmADC in the wild-type strain were obtained. These findings show that BmADC plays a crucial role in melanin metabolism and in the pigmentation pattern of the silkworm pupal stage. Finally, this study contributes to a better understanding of pupa pigmentation patterns in Lepidoptera.
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Li C, Zuo W, Tong X, Hu H, Qiao L, Song J, Xiong G, Gao R, Dai F, Lu C. A composite method for mapping quantitative trait loci without interference of female achiasmatic and gender effects in silkworm,Bombyx mori. Anim Genet 2015; 46:426-32. [DOI: 10.1111/age.12311] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2015] [Indexed: 11/27/2022]
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Tong X, Luo F, Liu Y, Zhang W, Xu Q, Zhang T, Li J, Chen L, Ma C. SU-E-T-620: Planning and Dosimetry for Pulsed Low Dose Rate RT for Recurrent Lung, Spine, GYN and Head and Neck Cancers. Med Phys 2015. [DOI: 10.1118/1.4924983] [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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Chen LM, Tong X, Li XB, Wu ZJ, Zhang YG. The association between the -2518A/G polymorphism in the MCP-1 gene and the risk of pulmonary tuberculosis in Sichuan Chinese population. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2015; 19:563-566. [PMID: 25753871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
OBJECTIVE The -2518A/G polymorphism in the Monocyte chemotactic protein-1 (MCP-1) gene may play an important role in regulating immunological reactions and may be associated with pulmonary tuberculosis (PTB). However, the relationship for the populations in Sichuan province of China remains unknown. The objective of the current study was to analysis that association. PATIENTS AND METHODS A total of 386 PTB patients and 398 controls were recruited. The genotypes were identified using PCR-RFLP and sequencing method. Data was analyzed using SPSS 11.0 software. RESULTS Significant association was found between the polymorphism and the risk of PTB: AG vs. AA: OR = 1.37, 95% CI = 0.98-1.92 and p = 0.06; GG vs. AA: OR = 1.69, 95% CI = 1.14-2.50 and p = 0.009; AG+GG vs. AA: OR = 1.47, 95% CI = 1.07-2.01 and p = 0.02; G vs. A: OR = 1.31, 95% CI = 1.08-1.60 and p = 0.007. CONCLUSIONS The current study suggested that the 2518A/G polymorphism in the MCP-1 gene was associated with risk of PTB in population of Sichuan province in China.
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Tong X, Aoyama H, Sudhakar S, Chen H, Bai D. The Residues in the First Extracellular Domain Play an Important Role in Transjunctional-Voltage Dependent Gating and Unitary Channel Conductance of Cx50 Gap Junction Channels. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.2414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Xu H, Zeng M, Li J, Tong X. Facile hydrothermal synthesis of flower-like Co-doped NiO hierarchical nanosheets as anode materials for lithium-ion batteries. RSC Adv 2015. [DOI: 10.1039/c5ra17017f] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Co-doped NiO hierarchical nanosheets with a flower-like morphology were synthesized using a facile hydrothermal process and characterized systematically by a variety of test means.
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Yang H, Wang Q, Zheng L, Zhan XF, Lin M, Lin F, Tong X, Luo ZY, Huang Y, Yang LY. Incidence and molecular characterization of Glucose-6-Phosphate Dehydrogenase deficiency among neonates for newborn screening in Chaozhou, China. Int J Lab Hematol 2014; 37:410-9. [PMID: 25440321 DOI: 10.1111/ijlh.12303] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Accepted: 09/02/2014] [Indexed: 01/06/2023]
Abstract
INTRODUCTION Glucose-6-phosphate dehydrogenase (G6PD) deficiency is highly prevalent in southern China. The aim of this study is to assess the extent of this disease in Chinese neonates and determine its molecular characteristics using a novel molecular screening method. METHODS A total of 2500 neonates were routinely screened for G6PD deficiency using a modified fluorescent spot test (FST). PCR-high-resolution melting (HRM) analysis was then used for the molecular assay. RESULTS The overall incidence of G6PD deficiency was 2.68% in our study cohort. Frequency in male population was 3.22% (44 neonates of 1365 male neonates), and in female population was 2.03% (23 neonates of 1135 female neonates). Of the 67 newborns suspected to be G6PD deficient based on FST (44 males, 23 females), 58 of 67 (87%) were detected with gene alterations. Seven kinds of mutations [c.95A>G, c.392G>T, c.493A>G, c.871G>A, c.1360C>T, c.1376G>T, and c.1388G>A] were identified by HRM analysis. CONCLUSION Routine newborn screening in Chaozhou, China with a relatively high prevalence of G6PD deficiency is justified and meets the World Health Organization recommendation. The usage of molecular diagnosis can favor the detection of heterozygotes which can be a supplement to regular newborn screening and useful for premarital and prenatal diagnosis for G6PD deficiency.
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Meng G, Dai F, Tong X, Li N, Ding X, Song J, Lu C. Genome-wide analysis of the WW domain-containing protein genes in silkworm and their expansion in eukaryotes. Mol Genet Genomics 2014; 290:807-24. [PMID: 25424044 DOI: 10.1007/s00438-014-0958-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 11/12/2014] [Indexed: 11/26/2022]
Abstract
WW domains are protein modules that mediate protein-protein interactions through recognition of proline-rich peptide motifs and phosphorylated serine/threonine-proline sites. WW domains are found in many different structural and signaling proteins that are involved in a variety of cellular processes. WW domain-containing proteins (WWCPs) and complexes have been implicated in major human diseases including cancer as well as in major signaling cascades such as the Hippo tumor suppressor pathway, making them targets for new diagnostics and therapeutics. There are a number of reports about the WWCPs in different species, but systematic analysis of the WWCP genes and its ligands is still lacking in silkworm and the other organisms. In this study, WWCP genes and PY motif-containing proteins have been identified and analyzed in 56 species including silkworm. Whole-genome screening of B. mori identified thirty-three proteins with thirty-nine WW domains located on thirteen chromosomes. In the 39 silkworm WW domains, 15 domains belong to the Group I WW domain; 14 domains were in Group II/III, 9 domains derived from 8 silkworm WWCPs could not be classified into any group, and Group IV contains only one WW domain. Based on gene annotation, silkworm WWCP genes have functions in multi-biology processes. A detailed list of WWCPs from the other 55 species was sorted in this work. In 14,623 silkworm predicted proteins, nearly 18 % contained PY motif, nearly 30 % contained various motifs totally that could be recognized by WW domains. Gene Ontology and KEGG analysis revealed that dozens of WW domain-binding proteins are involved in Wnt, Hedgehog, Notch, mTOR, EGF and Jak-STAT signaling pathway. Tissue expression patterns of WWCP genes and potential WWCP-binding protein genes on the third day of the fifth instar (L5D3) were examined by microarray analysis. Tissue expression profile analysis found that several WWCP genes and poly-proline or PY motif-containing protein genes took tissue- or gender-dependent expression manner in silkworms. We further analyzed WWCPs and PY motif-containing proteins in representative organisms of invertebrates and vertebrates. The results showed that there are no less than 16 and up to 29 WWCPs in insects, the average is 22. The number of WW domains in insects is no less than 19, and up to 47, the average is 36. In vertebrates, excluding the Hydrobiontes, the number of WWCPs is no less than 34 and up to 49, the average is 43. The number of WW domains in vertebrates is no less than 56 and up to 85, the average is 73. Phylogenetic analysis revealed that most homologous genes of the WWCP subfamily in vertebrates were duplicated during evolution and functions diverged. Nearly 1,000 PY motif-containing protein genes were found in insect genomes and nearly 2,000 genes in vertebrates. The different distributions of WWCP genes and PY motif-containing protein genes in different species revealed a possible positive correlation with organism complexity. In conclusion, this comprehensive bio-information analysis of WWCPs and its binding ligands would provide rich fundamental knowledge and useful information for further exploration of the function of the WW domain-containing proteins not only in silkworm, but also in other species.
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Misof B, Liu S, Meusemann K, Peters RS, Donath A, Mayer C, Frandsen PB, Ware J, Flouri T, Beutel RG, Niehuis O, Petersen M, Izquierdo-Carrasco F, Wappler T, Rust J, Aberer AJ, Aspock U, Aspock H, Bartel D, Blanke A, Berger S, Bohm A, Buckley TR, Calcott B, Chen J, Friedrich F, Fukui M, Fujita M, Greve C, Grobe P, Gu S, Huang Y, Jermiin LS, Kawahara AY, Krogmann L, Kubiak M, Lanfear R, Letsch H, Li Y, Li Z, Li J, Lu H, Machida R, Mashimo Y, Kapli P, McKenna DD, Meng G, Nakagaki Y, Navarrete-Heredia JL, Ott M, Ou Y, Pass G, Podsiadlowski L, Pohl H, von Reumont BM, Schutte K, Sekiya K, Shimizu S, Slipinski A, Stamatakis A, Song W, Su X, Szucsich NU, Tan M, Tan X, Tang M, Tang J, Timelthaler G, Tomizuka S, Trautwein M, Tong X, Uchifune T, Walzl MG, Wiegmann BM, Wilbrandt J, Wipfler B, Wong TKF, Wu Q, Wu G, Xie Y, Yang S, Yang Q, Yeates DK, Yoshizawa K, Zhang Q, Zhang R, Zhang W, Zhang Y, Zhao J, Zhou C, Zhou L, Ziesmann T, Zou S, Li Y, Xu X, Zhang Y, Yang H, Wang J, Wang J, Kjer KM, Zhou X. Phylogenomics resolves the timing and pattern of insect evolution. Science 2014; 346:763-7. [DOI: 10.1126/science.1257570] [Citation(s) in RCA: 1672] [Impact Index Per Article: 167.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Tong X, Kwong AD. Editorial Commentary: Barrier to Resistance: Lessons From 2 Direct-Acting Hepatitis C Virus Inhibitors, MK-5172 and Sofosbuvir. Clin Infect Dis 2014; 59:1675-7. [DOI: 10.1093/cid/ciu700] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Tong X, Aoyama H, Tsukihara T, Bai D. Charge at the 46th residue of connexin 50 is crucial for the gap-junctional unitary conductance and transjunctional voltage-dependent gating. J Physiol 2014; 592:5187-202. [PMID: 25260631 DOI: 10.1113/jphysiol.2014.280636] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Gap-junction (GJ) channels are twice the length of most membrane channels, yet they often have large unitary channel conductance (γj). What factors make this possibly the longest channel so efficient in passing ions are not fully clear. Here we studied the lens connexin (Cx) 50 GJs, which display one of the largest γj and the most sensitive transjunctional voltage-dependent gating (Vj gating) among all GJ channels. Introduction of charged residues into a putative pore-lining domain (the first transmembrane and the first extracellular loop border) drastically altered the apparent γj. Specifically, G46D and G46E increased the Cx50 γj from 201 to 256 and 293 pS, respectively and the G46K channel showed an apparent γj of only 20 pS. G46K also drastically altered Vj gating properties in homotypic G46K and heterotypic Cx50/G46K channels, causing an apparent loss of fast Vj-dependent gating transitions and leaving only loop gating transitions at the single channel current records. Both macroscopic and single channel currents of heterotypic Cx50/G46K channels showed a prominent rectification. Our homology structural models indicate that the pore surface electrostatic potentials are a dictating factor in determining the γj. Our data demonstrate, at the whole GJ channel level, a crucial role of the surface charge properties in the first transmembrane/first extracellular border domain in determining the efficiency of ion permeation and the Vj gating of Cx50 and possibly other GJ channels.
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Wu HJ, Zhao LD, Zheng FS, Wu D, Pei YL, Tong X, Kanatzidis MG, He JQ. Broad temperature plateau for thermoelectric figure of merit ZT>2 in phase-separated PbTe0.7S0.3. Nat Commun 2014; 5:4515. [PMID: 25072798 DOI: 10.1038/ncomms5515] [Citation(s) in RCA: 152] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 06/26/2014] [Indexed: 11/09/2022] Open
Abstract
Thermoelectrics interconvert heat to electricity and are of great interest in waste heat recovery, solid-state cooling and so on. The efficiency of thermoelectric materials depends directly on the average ZT (dimensionless figure of merit) over a certain temperature range, which historically has been challenging to increase. Here we report that 2.5% K-doped PbTe0.7S0.3 achieves a ZT of >2 for a very wide temperature range from 673 to 923 K and has a record high average ZT of 1.56 (corresponding to a theoretical energy conversion efficiency of ~20.7% at the temperature gradient from 300 to 900 K). The PbTe0.7S0.3 composition shows spinodal decomposition with large PbTe-rich and PbS-rich regions where each region exhibits dissimilar types of nanostructures. Such high average ZT is obtained by synergistically optimized electrical- and thermal-transport properties via carrier concentration tuning, band structure engineering and hierarchical architecturing, and highlights a realistic prospect of wide applications of thermoelectrics.
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Jiang CY, Tong X, Brown DR, Chi S, Christianson AD, Kadron BJ, Robertson JL, Winn BL. Development of a compact in situ polarized ³He neutron spin filter at Oak Ridge National Laboratory. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:075112. [PMID: 25085178 DOI: 10.1063/1.4890391] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We constructed a compact in situ polarized (3)He neutron spin filter based on spin-exchange optical pumping which is capable of continuous pumping of the (3)He gas while the system is in place in the neutron beam on an instrument. The compact size and light weight of the system simplifies its utilization on various neutron instruments. The system has been successfully tested as a neutron polarizer on the triple-axis spectrometer (HB3) and the hybrid spectrometer (HYSPEC) at Oak Ridge National Laboratory. Over 70% (3)He polarization was achieved and maintained during the test experiments. Over 90% neutron polarization and an average of 25% transmission for neutrons of 14.7 meV and 15 meV was also obtained.
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Li Y, Xue F, Xu SZ, Wang XW, Tong X, Lin XJ. Lycopene protects bone marrow mesenchymal stem cells against ischemia-induced apoptosis in vitro. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2014; 18:1625-1631. [PMID: 24943973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE Bone marrow mesenchymal stem cells (MSCs) have been identified to have the potential to differentiate into multiple types of cells. And the therapy based on transplantation of MSCs in some solid organs has been suggested in recent years. However, the rejection reaction often occurs in the transplantation of MSCs and could induce cell death. Ischemia has been reported to one of the main causes of MSCs death during transplantation. The primary objective of this study was to verify whether a natural antioxidant, lycopene, could protect MSCs from ischemia-induced apoptosis in vitro. MATERIALS AND METHODS MSCs were isolated from bone marrow in mice femoral bone marrow. The effect of lycopene on MSCs during oxygen-glucose-serum deprivation was investigated. RESULTS We found that lycopene protected MSCs from serum deprivation- and hypoxia-induced apoptosis. The reactive oxygen species (ROS) generation and inducible nitric oxide synthetase expression were also inhibited dose-dependently by lycopene. Further investigation revealed that lycopene could activate phosphoinositide-3 kinase (PI3K)/Akt. Pretreatment with PI3K/Akt inhibitors prevented the protective effect of lycopene on MSCs. CONCLUSIONS Lycopene could protect MSCs from ischemia-induced apoptosis through reducing ROS generation; therefore, lycopene could be useful in MSC transplantation.
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Ni W, Qian W, Tong X. Cryptotanshinone Induces Apoptosis of HL-60 Cells via Mitochondrial Pathway. TROP J PHARM RES 2014. [DOI: 10.4314/tjpr.v13i4.9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Tong X, Xiao D, Yao F, Huang T. Astragalus membranaceus as a cause of increased CA19-9 and liver and kidney cysts: a case report. J Clin Pharm Ther 2014; 39:561-3. [PMID: 24806627 DOI: 10.1111/jcpt.12173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 04/15/2014] [Indexed: 01/22/2023]
Abstract
WHAT IS KNOWN AND OBJECTIVE Astragalus membranaceus, one of the most common Chinese herbs, is widely used to prevent and treat a variety of diseases. Very few adverse reactions, caused by A. membranaceus, have been reported in the literature. The purpose of this article was to report a case of marked increase in carbohydrate antigen 19-9 (CA19-9) and the formation of liver and kidney cysts following oral administration of A. membranaceus. CASE SUMMARY A 38-year-old woman was found to have a high serum CA19-9 level (156 U/mL) at her routine annual examination. On follow-up, several small cysts were found in her left kidney and liver by CT scan. Her medical history showed that she had taken Astragalus tea every day for 1 month. One month after she stopped taking it, the CA19-9 level decreased to 40·19 U/mL. Ten months later, PET-CT showed that there were no liver and kidney cysts. However, she took Astragalus powder again in the second year and 1 month later her CA19-9 level increased again to more than 1000 U/mL. Several small cysts were again seen in her left kidney and liver by enhanced CT. Her CA19-9 level gradually became normal after she stopped taking the Astragalus powder. WHAT IS NEW AND CONCLUSION This case strongly suggests that oral administration of A. membranaceus may lead to increase in CA19-9 and the formation of liver and kidney cysts.
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Sun Y, Tong X, Chen H, Huang T, Shao Q, Huang W, Laird DW, Bai D. An atrial-fibrillation-linked connexin40 mutant is retained in the endoplasmic reticulum and impairs the function of atrial gap-junction channels. Dis Model Mech 2014; 7:561-9. [PMID: 24626989 PMCID: PMC4007407 DOI: 10.1242/dmm.013813] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 03/11/2014] [Indexed: 12/18/2022] Open
Abstract
Connexin40 (Cx40)-containing gap-junction channels are expressed in the atrial myocardium and provide a low-resistance passage for rapid impulse propagation. A germline mutation in the GJA5 gene, which encodes Cx40, resulting in a truncated Cx40 (Q49X) was identified in a large Chinese family with lone (idiopathic) atrial fibrillation (AF). This mutation co-segregated with seven AF probands in an autosomal-dominant way over generations. To test the hypothesis that this Cx40 mutant affects the distribution and function of atrial gap junctions, we studied the Q49X mutant in gap-junction-deficient HeLa and N2A cells. The Q49X mutant, unlike wild-type Cx40, was typically localized in the cytoplasm and failed to form gap-junction plaques at cell-cell interfaces. When the Q49X mutant was co-expressed with Cx40 or Cx43, the mutant substantially reduced the gap-junction plaque formation of Cx40 and Cx43. Electrophysiological studies revealed no electrical coupling of cell pairs expressing the mutant alone and a significant decrease in the coupling conductance when the mutant was co-expressed with Cx40 or Cx43. Further colocalization experiments with the organelle residential proteins indicate that Q49X was retained in the endoplasmic reticulum. These findings provide evidence that the Q49X mutant is capable of impairing gap-junction distribution and function of key atrial connexins, which might play a role in the predisposition to and onset of AF.
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