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Cheng YD, Duan CJ, Dong S, Zhang H, Zhang SK, Wang SQ, Zhang CF. Clinical controlled comparison between lobectomy and segmental resection for patients over 70 years of age with clinical stage I non-small cell lung cancer. Eur J Surg Oncol 2012; 38:1149-55. [PMID: 22901959 DOI: 10.1016/j.ejso.2012.08.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 07/19/2012] [Accepted: 08/02/2012] [Indexed: 11/15/2022] Open
Abstract
AIMS The standard surgical procedure for elderly (≥ 70 years) patients with clinical stage I non-small cell lung cancer (NSCLC) was investigated. METHODS A non-randomized prospective controlled study was conducted to compare lobectomy with segmental resection for the treatment of elderly clinical stage I lung cancer patients under different pulmonary function. Perioperative indicators including time and volume of thoracic drainage, incidence of postoperative complications, locoregional recurrence rates, and 1, 3, and 5-year survival rates were analyzed. RESULTS A total of 184 patients were included in the study. Patients were classified into two groups according to pulmonary function: group 1 included 64 patients who had poor pulmonary function, with a forced expiratory volume in 1 s (FEV(1)) of less than 1.5 L, whereas group 2 consisted of 120 patients with an FEV(1) ≥ 1.5 L. The patients in group 1 had a longer postoperative mechanical ventilation time and a higher incidence rate of respiratory associated complications than those in group 2 (21.9 vs. 8.35%, p = 0.009). The local recurrence and long-term survival rates were not significantly different between lobectomy and segmental resection. Among the patients who underwent segmental resection, those who had regional lymph node dissection showed a higher 3-year and 5-year survival rate than those undergoing selected lymph node resection (77.8 vs. 51.7%, p = 0.042; 55.6 vs. 27.6%, p = 0.034), but this was not significant in lobectomy. CONCLUSIONS Segmental resection combined with regional lymph node resection could be the best choice for elderly clinical stage I NSCLC patients with FEV(1) < 1.5 L.
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Dong S, Hu Y, Du W, Tao W, Zhang X, Zhuang P, Li Y. Changes in Spontaneous Dorsal Horn Potentials after Dorsal Root Entry Zone Lesioning in Patients with Pain after Brachial Plexus Avulsion. J Int Med Res 2012; 40:1499-506. [PMID: 22971502 DOI: 10.1177/147323001204000429] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVES: This study investigated spontaneous dorsal horn potentials in patients with pain after brachial plexus avulsion and determined the effect of dorsal root entry zone (DREZ) lesioning on these potentials and on pain levels. METHODS: Electrospinography (ESG) recordings were undertaken in seven patients using a noninvasive electrocorticography strip electrode. Measurements were taken from the DREZ on the intact side of the spinal cord before lesioning of the injured DREZ and from the injured DREZ before and after lesioning. RESULTS: DREZ lesioning had a significant positive effect on pain at 12 months postoperatively. At 15.0 Hz, the mean ESG power from the injured DREZ before lesioning was significantly higher than that from the intact DREZ. In addition, the mean ESG power from the injured DREZ after successful DREZ lesioning was significantly lower than that from the intact DREZ and that from the injured DREZ before lesioning. CONCLUSIONS: The ESG power from the injured DREZ increases in patients with pain after brachial plexus avulsion compared with that of the intact DREZ; this increase is reduced by successful DREZ lesioning.
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Fan H, Chen L, Zhang F, Quan Y, Su X, Qiu X, Zhao Z, Kong KL, Dong S, Song Y, Chan THM, Guan XY. MTSS1, a novel target of DNA methyltransferase 3B, functions as a tumor suppressor in hepatocellular carcinoma. Oncogene 2012; 31:2298-308. [PMID: 21909138 DOI: 10.1038/onc.2011.411] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 07/13/2011] [Accepted: 07/20/2011] [Indexed: 01/16/2023]
Abstract
DNA methyltransferase 3B (DNMT3B) mediates gene silencing via epigenetic mechanisms during hepatocellular carcinoma (HCC) progression. We aimed to identify novel targets of DNMT3B and their potential regulatory mechanisms in HCC. Metastasis suppressor 1 (MTSS1) was one of the DNMT3B targets and selected for further study. DNMT3B overexpression was detected in 81.25% of clinical HCC specimens and was negatively associated with MTSS1 in HCC cells and clinical samples. The underlying mechanism by which DNMT3B silences MTSS1 was studied using a combination of methylation-specific polymerase chain reaction (PCR) and bisulfite genome sequencing, chromatin immunoprecipitation-PCR and luciferase reporter assays. We found that the MTSS1 promoter region was sparsely methylated, and the methylation inhibitors failed to abolish DNMT3B-mediated MTSS1 silencing. DNMT3B protein bound directly to the 5'-flanking region (-865/-645) of the MTSS1 gene to inhibit its transcription. The functional role of MTSS1 was investigated using in vitro and in vivo tumorigenicity assays. As a result, MTSS1 exerted tumor suppressor effects and arrested cells in the G2/M phase, but not the G1/S phase of the cell cycle when it was depleted or overexpressed in HCC cells. Taken together, MTSS1, a novel target of DNMT3B, is repressed by DNMT3B via a DNA methylation-independent mechanism. MTSS1 was further characterized as a novel tumor suppressor gene in HCC. These findings highlight how DNMT3B regulates MTSS1, and such data may be useful for the development of new treatment options for HCC.
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Zhuang P, Hallett M, Dong S, Zhang X, Zhang Y, Li J, Li Y. Electrode Contact Location Correlates with the Location of Tic-Related Neuronal Activity in the Globus Pallidus Internus in Patients with Tics (P01.189). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.p01.189] [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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Shan Y, Lin N, Yang X, Tan J, Zhao R, Dong S, Wang S. Sulphoraphane inhibited the expressions of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 through MyD88-dependent toll-like receptor-4 pathway in cultured endothelial cells. Nutr Metab Cardiovasc Dis 2012; 22:215-222. [PMID: 20880684 DOI: 10.1016/j.numecd.2010.06.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Revised: 06/17/2010] [Accepted: 06/21/2010] [Indexed: 11/15/2022]
Abstract
BACKGROUND AND AIMS Chronic inflammation plays pivotal roles in both cancer and cardiovascular diseases. A large body of evidence suggests that high intake of cruciferous vegetables is closely related with low risk of these disorders. However, the underlying mechanisms of protection are not fully understood. The aim of this study is to test the protective effects of an isothiocyanate sulphoraphane on inflammatory injury and related regulation pathways in cultured endothelial cells. METHODS AND RESULTS The expressions of adhesion molecules were determined by TaqMan real-time polymerase chain reaction (PCR) and Western blot analysis. Nuclear factor-kappa B (NF-кB) translocation was detected by immunofluorescent hybridisation. Other proteins were measured by Western blot analysis. The results demonstrated that sulphoraphane significantly suppresses the expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 stimulated by lipopolysaccharide (LPS) both at the transcriptional and translational levels. In addition, sulphoraphane inhibited the translocation of NF-кB into the nucleus. Sulphoraphane decreased the phosphorylation of extra-cellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK), while further blockade and activation using individually specific agents confirm that p38 MAPK and JNK are mainly involved. Interestingly, sulphoraphane down-regulated Toll-like receptor (TLR)-4, a receptor of LPS located on the membrane. In addition, MyD88, an effector downstream TLR-4 signal pathway was subsequently attenuated. CONCLUSION Taken all together, adhesion molecules are confirmed to be the novel targets of sulphoraphane in preventing inflammatory insult to endothelial cells. Sulphoraphane suppressed TLR-4 followed by MyD88 and downstream factors such as p38 MAPK and JNK, ultimately blocking NF-кB translocation and the subsequent expression of adhesion molecules. These data suggested a novel inflammatory pathway mediated by sulphoraphane.
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Li C, Dong S, Wang H, Hu Y. Microarray analysis of gene expression changes in the brains of NR2B-induced memory-enhanced mice. Neuroscience 2011; 197:121-31. [PMID: 21925573 DOI: 10.1016/j.neuroscience.2011.08.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 08/11/2011] [Accepted: 08/13/2011] [Indexed: 01/13/2023]
Abstract
Glutamate N-methyl-D-aspartate (NMDA) receptors play a pivotal role in different forms of memory. The dysfunction of NMDA receptors contributes to the pathology of central nervous system (CNS) disorders. To further investigate the role of the NMDA receptors in brain processes, we analyzed and compared the gene expression profiles in the hippocampus of NR2B overexpression-induced memory-enhanced mice (Tg mice) with those of their wild-type littermates. Results reveal that 249 genes, which are mainly involved in neurotransmission, signal transduction, cytoskeletal structure, hormone activity, and transcription, were significantly affected in Tg mice. Interestingly, the intracellular calcium channel proteins ryanodine receptor (RyR) 1 and 3, as well as functionally related proteins such as the histidine-rich calcium-binding protein and triadin 2, were upregulated. The Homer-1c protein was also increased in Tg mice and formed a complex with the RyR protein in the mouse brain, suggesting that Homer-1c is an important modulator in both intracellular calcium signaling and overall neuronal signaling by simultaneously interacting with the NMDA receptors and RyR. Western blot and real-time PCR results show that the expression of phospho-CREB, c-fos, and the immediate-early genes Egr2 and Egr4 were also upregulated in Tg mice. The current study demonstrates that a chronic increase in the activation of NMDA receptors affected the expression of a large number of genes and may provide important clues for a better understanding of the molecular mechanism of NMDA receptor-modulated learning and memory, as well as of CNS disorders.
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Zhang Y, Zhang X, Wu YL, Zhang G, Cheng H, Dong S. Expression of Adam28 as a prognostic biomarker of survival in patients with early-stage non-small cell lung cancer. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.10600] [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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Zhong W, Yang X, Liao R, Nie Q, Dong S, Su J, Zhang X, Zhou Q, Yang J, Wu YL. Induction erlotinib or gemcitabine/carboplatin factorial assignment therapy in stage IIIA-N2 non-small cell lung cancer. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.e17512] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Dong S, Terasaka S, Kiyama R. Bisphenol A induces a rapid activation of Erk1/2 through GPR30 in human breast cancer cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2011; 159:212-218. [PMID: 20875696 DOI: 10.1016/j.envpol.2010.09.004] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 08/30/2010] [Accepted: 09/05/2010] [Indexed: 05/29/2023]
Abstract
Bisphenol A (BPA) has been considered as an endocrine disruptor due to its ability to interact with estrogen receptors (ERs). While G protein-coupled receptor 30 (GPR30) is a novel estrogen receptor, its role in BPA-induced activation of Erk1/2 remains unknown. Human breast cancer cell lines, MCF-7, MDA-MB-231 and SKBR3, were used as experimental models to discriminate between ERs-dependent, putative ERs-independent and/or GPR30-associated effects. BPA induced a rapid activation of Erk1/2 in both ERα/β-positive and negative breast cancer cells, and this effect was not blocked with an ER antagonist, ICI 182,780. A small interfering RNA assay revealed that the expression of GPR30 was necessary for BPA-induced activation of Erk1/2 and transcriptional regulation of c-fos. In addition, BPA regulates the expression of c-fos likely through an AP1-mediated pathway. As a conclusion, GPR30 plays an important role in the BPA-induced activation of Erk1/2 in a manner distinguishable from that in ERα-mediated signaling.
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Zhou D, Bi XT, Dong S. Contribution of hydrodynamic characteristics on the performance of an aerobic biofilm conical fluidized bed. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2011; 63:1160-1167. [PMID: 21436551 DOI: 10.2166/wst.2011.355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The performance of a conical fluidized bed (TFB) bioreactor, including the biofilm thickness, microbial space density, microbial cell matrix and its efficiency for COD degradation at a bed expansion ratio of 14 to 90%, was studied and compared with a cylindrical fluidized bed (CFB) bioreactor. The hydrodynamic characteristics of the TFB, especially the internal-circulation of bioparticles associated with its unique tapered geometry of the bed, created a much more uniform axial distribution of the bioparticles, leading to the formation of thinner and more compacted biofilms in the TFB compared to that in the CFB. The thinner biofilm in the TFB tended to be stable and possessed more than 6 times of microbial population density compared to the CFB. As a result, thinner biofilms in the TFB contributed to a higher COD removal efficiency, which remained at over 95% at operated expansion ratios, about 15 to 25% higher than that in the CFB.
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Maiella S, Dong S, Becavin C, Coffre M, Placek K, Bianchi E, Benecke A, Rogge L. Single-cell gene profiling analysis of human regulatory T cell subsets. Lab Invest 2010. [PMCID: PMC3007773 DOI: 10.1186/1479-5876-8-s1-p3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Qiu JJ, Chu H, Lu X, Jiang X, Dong S. The reduced and altered activities of PAX5 are linked to the protein-protein interaction motif (coiled-coil domain) of the PAX5-PML fusion protein in t(9;15)-associated acute lymphocytic leukemia. Oncogene 2010; 30:967-77. [PMID: 20972455 DOI: 10.1038/onc.2010.473] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The paired box domain of PAX5 was reported to fuse with the sequence of promyelocytic leukemia (PML) to produce PAX5-PML chimeric protein in two patients with B-cell acute lymphoblastic leukemia. In the present studies, we found, by gel shift assays, that PAX5-PML bound to a panel of PAX5-consensus sequence acts as a homodimer with reduction of its DNA-binding affinities in comparison with wild-type PAX5. In transient transfection assays using 293T and HeLa cells, and retrovirus transduction of murine hematopoietic stem/progenitor cells together with quantitative real-time polymerase chain reaction analysis, PAX5-PML inhibited wild-type PAX5 target gene transcriptional activity. Studies comparing PAX5-PML with PAX5-PML(ΔCC) demonstrated that the coiled-coil (CC) protein interaction domain located within the PML moiety was required for PAX5-PML homodimer complex formation and partial transcriptional repression of genes controlled by PAX5. Fluorescent microscopic examination of transiently expressed YFP-tagged proteins in HeLa and 293T cells demonstrated that YFP-PAX5-PML and YFP-PAX5-PML(ΔCC) exhibited a diffuse granular pattern within the nucleus, similar to PAX5 but not PML. By fluorescent recovery after photobleach (FRAP), we have shown that PAX5-PML fusion protein has reduced intranuclear mobility compared with wild-type PAX5. Furthermore, the dimerization domain (CC) of PML was responsible for the reduced intranuclear mobility of PAX5-PML. These results indicate that the CC domain of PAX5-PML is important for each of the known activities of PAX5-PML fusion proteins.
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Xu K, Rajagopal S, Klebba I, Dong S, Ji Y, Liu J, Kuperwasser C, Garlick JA, Naber SP, Buchsbaum RJ. The role of fibroblast Tiam1 in tumor cell invasion and metastasis. Oncogene 2010; 29:6533-42. [PMID: 20802514 PMCID: PMC2997941 DOI: 10.1038/onc.2010.385] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The co-evolution of tumors and their microenvironment involves bidirectional communication between tumor cells and tumor-associated stroma. Various cell types are present in tumor-associated stroma, of which fibroblasts are the most abundant. The Rac exchange factor Tiam1 is implicated in multiple signaling pathways in epithelial tumor cells and lack of Tiam1 in tumor cells retards tumor growth in Tiam1 knock-out mouse models. Conversely, tumors arising in Tiam1 knock-out mice have increased invasiveness. We have investigated the role of Tiam1 in tumor-associated fibroblasts as a modulator of tumor cell invasion and metastasis, using retroviral delivery of short hairpin RNA to suppress Tiam1 levels in three different experimental models. In spheroid co-culture of mammary epithelial cells and fibroblasts, Tiam1 silencing in fibroblasts led to increased epithelial cell outgrowth into matrix. In tissue-engineered human skin, Tiam1 silencing in dermal fibroblasts led to increased invasiveness of epidermal keratinocytes with premalignant features. In a model of human breast cancer in mice, co-implantation of mammary fibroblasts inhibited tumor invasion and metastasis, which was reversed by Tiam1 silencing in co-injected fibroblasts. These results suggest that stromal Tiam1 may play a role in modulating the effects of the tumor microenvironment on malignant cell invasion and metastasis. This suggests a set of pathways for further investigation, with implications for future therapeutic targets.
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Dong S, Rodger J, Mulders WHAM, Robertson D. Tonotopic changes in GABA receptor expression in guinea pig inferior colliculus after partial unilateral hearing loss. Brain Res 2010; 1342:24-32. [PMID: 20438718 DOI: 10.1016/j.brainres.2010.04.067] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 04/21/2010] [Accepted: 04/21/2010] [Indexed: 11/28/2022]
Abstract
Immunohistochemistry was used to investigate the topographic distribution of the alpha1 subunit of the GABA receptor (GABRA1) in guinea pig inferior colliculus after treatments that caused a unilateral loss of peripheral neural sensitivity in the high-frequency regions of the cochlea. Both forms of treatment (direct mechanical lesion of the cochlea and acoustic overstimulation) resulted in a significant decrease in GABRA1 labeling in regions of the contralateral inferior colliculus in which high-frequency sound stimuli are represented. This localized region of reduced inhibitory receptor expression corresponds to the region in which hyperactivity of inferior colliculus neurons has been shown to develop after such treatments. The results strengthen the notion of a causal link between reduced GABRA1 expression and neural hyperactivity in central auditory nuclei and provide a possible mechanism for the development of phantom auditory sensations, or tinnitus.
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Cheng H, Wu Y, An S, Zhang X, Dong S, Zhang Y. In vitro sequence-dependent synergism between paclitaxel and gefitinib in human lung cancer cell lines. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e21109] [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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Dong S, Zhang X, Cheng H, Guo A, Zhu J, Yang S, Wu Y. Effect of everolimus and gefitinib on PI3K/akt/mTOR and raf/MEK/ERK pathways in NSCLC cells. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e13654] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Zhou D, Dong S, Zhang F. Abatement efficiency and controlling strategy of a cylindrical and a conical fluidized bed flocculator. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2010; 62:852-858. [PMID: 20729588 DOI: 10.2166/wst.2010.315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The aggregation efficiency of colloidal kaolin particles by the turbulence caused by random movement of silica gel beads in a cylindrical (CFB) and an 8 degrees conical fluidized bed (TFB) was studied in this paper, focusing on the control strategies of these novel processes. The abatement efficiencies as a function of the Camp number, velocity gradient (G) and flocculation time (T) were exploited. In general, the abatement efficiency tended to be improved with the increase of Camp number (in the study range of this work: Camp number lower than 8058 and 5639 in CFB and TFB, respectively). However, the efficiency was relatively low and sensitive to the Camp number as G was more than 186 s⁻¹ in CFB and 178 s⁻¹ in TFB, respectively. Whereas, increasing flocculation time clearly contributed to the improvement of the abatement efficiency, which is considered to be an effective strategy to enhance the treatment ability. Velocity gradient and flocculation time could be controlled by means of superficial liquid velocity and properties of packing particles. It should be noted that the backmixing in the TFB caused formed flocs to break and thus lower abatement efficiencies were found in the TFB than those in the CFB.
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Akamatsu T, Wang D, Wang K, Li S, Dong S. Scanning sonar of rolling porpoises during prey capture dives. J Exp Biol 2010; 213:146-52. [PMID: 20008371 DOI: 10.1242/jeb.037655] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Dolphins and porpoises have excellent biosonar ability, which they use for navigation, ranging and foraging. However, the role of biosonar in free-ranging small cetaceans has not been fully investigated. The biosonar behaviour and body movements of 15 free-ranging finless porpoises (Neophocaena phocaenoides) were observed using electronic tags attached to the animals. The porpoises often rotated their bodies more than 60 deg., on average, around the body axis in a dive bout. This behaviour occupied 31% of the dive duration during 186 h of effective observation time. Rolling dives were associated with extensive searching effort, and 23% of the rolling dive time was phonated, almost twice the phonation ratio of upright dives. Porpoises used short inter-click interval sonar 4.3 times more frequently during rolling dives than during upright dives. Sudden speed drops, which indicated that an individual turned around, occurred 4.5 times more frequently during rolling dives than during upright dives. Together, these data suggest that the porpoises searched extensively for targets and rolled their bodies to enlarge the search area by changing the narrow beam axis of the biosonar. Once a possible target was detected, porpoises frequently produced short-range sonar sounds. Continuous searching for prey and frequent capture trials appeared to occur during rolling dives of finless porpoises. In contrast, head movements ranging ±2 cm, which can also change the beam axis, were regularly observed during both dives. Head movements might assist in instant assessment of the arbitrary direction by changing the beam axis rather than prey searching and pursuit.
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Dong S. Evidence for internal structures of spiral turbulence. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:067301. [PMID: 20365305 DOI: 10.1103/physreve.80.067301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Revised: 11/19/2009] [Indexed: 05/29/2023]
Abstract
We present several observations into spiral turbulence in a Taylor-Couette geometry gained through a three-dimensional direct numerical simulation. Conditionally averaged flow statistics show the persistence of an azimuthal gradient of the mean flow across both the turbulent and laminar spirals, and distinct distribution features of the turbulent intensity. The data provide a physical picture qualitatively different from the existing model of spiral turbulence. Certain aspects of the spiral pattern are observed to bear similarities to the stationary laminar-turbulent pattern in plane Couette flow.
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Cheng H, Wu Y, An S, Dong S, Chen H, Zhang X, Guo A. In vitro sequence-dependent interaction between paclitaxel and gefitinib in human lung cancer cell lines. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e22025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e22025 Background: Cytotoxicity chemotherapy has been standard first line treatment for advanced NSCLC. Clinical trials comparing first line EGFR TKI therapy over cytotoxicity chemotherapy are under investigation in phase III trials. The aim of this study is to test the hypothesis that paclitaxel followed by gefitinib would be superior to the opposite order in EGFR TKI resistant cell lines because of cell signaling pathway and cell cycle interaction. Methods: we have used EGFR-TKI resistant human lung cancer cell lines A549, H1975 and H1650 as an in vitro model for defining the differential effects of opposite sequence of combination of cytotoxic drug and anti- EGFR agents on cell growth, signaling pathway, cell cycle distribution and induction of apoptosis. Results: Paclitaxel 24 hours followed by gefitinib 72 hours in A549, H1975 and H1650 cells produced synergistic effects, while the reverse sequence produced antagonistic effects. Exposure to paclitaxel resulted in an increased pEGFR and pAKT level, this increase of phosphorylation can be inhibited by the following gefitinib exposure, while the reverse sequence resulted in no change in EGFR and AKT phosphorylation. We confirmed that gefitinib arrested the cells in G1, paclitaxel arrested cells in S phase. The sequence of paclitaxel followed by gefitinib cause cells arrested in G1, while the reverse sequence cause cells arrested in S and G2 phase. Conclusions: These findings suggest that the sequence of paclitaxel followed by gefitinib may be superior to the reverse sequence in gefitinib resistant NSCLC, and support the investigation of these sequential treatment in the clinical setting. This work was supported by the grants from the National Natural Science Foundation of China (No. 30772531). No significant financial relationships to disclose.
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Liu P, Huang G, Dong S, Wan L. Kinetic analysis of experimental rabbit tumour and inflammation model with 18F-FDG PET/CT. Nuklearmedizin 2009; 48:153-8. [PMID: 19384450 DOI: 10.3413/nukmed-0201] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2008] [Accepted: 02/20/2009] [Indexed: 11/20/2022]
Abstract
UNLABELLED Non-specific accumulation of 18F-FDG by both tumour and inflammatory lesions can make diagnostic analysis difficult. Our aim was to explore the difference in 18F-FDG uptake kinetics between tumour and inflammatory cells. To this end, we investigated VX2 tumour lesions and inflammatory lesions in rabbits. METHODS Six rabbits with VX2 tumour cells transplanted into one forelimb muscle and inflammatory lesions induced by turpentine oil in the contralateral forelimb were scanned for 60 minutes post 18F-FDG injection. Imaging data was analyzed with the standard 2-tissue-compartment model. Parameters, VB, Ki, K1, k2, k3, k4, were compared between tumour and inflammatory lesions. SUV and dual time scan methods were also compared in the experiment. RESULTS Time activity curves of VX2 tumour lesions showed a characteristic pattern of gradually increasing 18F-FDG uptake up to 60 min, whereas, 18F-FDG uptake in inflammatory lesions increased more slowly than in tumours. Parameters estimated from the uptake process showed that forward transport constant, K1, and influx constant, Ki, values in VX2 tumour lesions (0.186 +/- 0.053 and 0.048 +/- 0.014, respectively) was significantly higher than that in inflammatory lesions (0.129 +/- 0.024 and 0.022 +/- 0.007, respectively) (p < 0.05). In contrast, mean values of VB, k2, k3 and k4 derived from VX2 tumours were not significantly different from that of inflammatory lesions. SUVs at 60 minutes post 18F-FDG injection were also significantly higher in the VX2 tumor lesions than in the inflammatory lesions. Retention index (RI) was not significantly different between VX2 tumours and inflammatory lesions (1.134 +/- 0.076 vs. 1.060 +/- 0.058, p > 0.05). CONCLUSION Different kinetic parameters (Ki, K1, k3) exist between inflammatory and tumour lesions.
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Dong S, Clayton DF. Partial dissociation of molecular and behavioral measures of song habituation in adult zebra finches. GENES BRAIN AND BEHAVIOR 2009; 7:802-9. [PMID: 19125865 DOI: 10.1111/j.1601-183x.2008.00423.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Initial playback of recorded birdsong triggers a number of responses in zebra finches, including overt listening behavior and ERK pathway-dependent activation of zenk gene transcription in the auditory lobule of the forebrain. Repetition of one song stimulus leads to persistent habituation of these responses, as measured by subsequent presentations 1 day later. In this study, we examined the causal relationships between behavioral and molecular (ERK/zenk) habituation. In a within-subject comparison, we found a strong correlation with the level of prior training for both responses (duration of behavioral listening and magnitude of zenk expression), but little correlation between these responses for birds within the same treatment group. We then tested the hypothesis that ERK/zenk activation during training is necessary for the development of habituation measured 1 day later. Cannula-directed infusion of a pharmacological inhibitor of ERK activation (U0126) immediately before training blocked the development of habituation of the zenk gene response. However, measurement of the effect on behavioral habituation was confounded because birds that were infused with a non-active drug analogue (U0124) showed a decreased response 1 day later, even to novel songs. We conclude that the behavioral response to song stimulation is strongly influenced by factors other than song familiarity, whereas the zenk response in the forebrain may be a more accurate indicator of actual experience hearing a particular song.
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Dong S, Mulders W, Rodger J, Robertson D. Changes in neuronal activity and gene expression in guinea-pig auditory brainstem after unilateral partial hearing loss. Neuroscience 2009; 159:1164-74. [DOI: 10.1016/j.neuroscience.2009.01.043] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 01/20/2009] [Accepted: 01/22/2009] [Indexed: 11/24/2022]
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Akamatsu T, Wang D, Wang K, Li S, Dong S, Zhao X, Barlow J, Stewart BS, Richlen M. Estimation of the detection probability for Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) with a passive acoustic method. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2008; 123:4403-4411. [PMID: 18537391 DOI: 10.1121/1.2912449] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Yangtze finless porpoises were surveyed by using simultaneous visual and acoustical methods from 6 November to 13 December 2006. Two research vessels towed stereo acoustic data loggers, which were used to store the intensity and sound source direction of the high frequency sonar signals produced by finless porpoises at detection ranges up to 300 m on each side of the vessel. Simple stereo beam forming allowed the separation of distinct biosonar sound source, which enabled us to count the number of vocalizing porpoises. Acoustically, 204 porpoises were detected from one vessel and 199 from the other vessel in the same section of the Yangtze River. Visually, 163 and 162 porpoises were detected from two vessels within 300 m of the vessel track. The calculated detection probability using acoustic method was approximately twice that for visual detection for each vessel. The difference in detection probabilities between the two methods was caused by the large number of single individuals that were missed by visual observers. However, the sizes of large groups were underestimated by using the acoustic methods. Acoustic and visual observations complemented each other in the accurate detection of porpoises. The use of simple, relatively inexpensive acoustic monitoring systems should enhance population surveys of free-ranging, echolocating odontocetes.
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Dong S, Triantafyllou GS, Karniadakis GE. Elimination of vortex streets in bluff-body flows. PHYSICAL REVIEW LETTERS 2008; 100:204501. [PMID: 18518541 DOI: 10.1103/physrevlett.100.204501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2007] [Indexed: 05/26/2023]
Abstract
We present an effective technique for suppressing the vortex-induced vibrations of bluff bodies by eliminating the von Kármán street formed in their wake. Specifically, we find that small amounts of combined windward suction and leeward blowing around the body modify the wake instability and lead to suppression of the fluctuating lift force. Three-dimensional simulations and stability analysis are employed to quantify our findings for the flow past fixed and flexibly mounted circular cylinders.
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