526
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Fan J, Fourka E, Hayes S, Jin L, Wang L, Price R, Ma C. SU-E-T-887: Cyberknife Treatment for Early Stage Oral Tongue Cancer - Feasibility Study. Med Phys 2011. [DOI: 10.1118/1.3612851] [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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527
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Wang L, Fan J, Lin T, Jin L, Ma C. SU-E-T-521: Is Cone Beam CT (CBCT) Equivalent to 4-Dimensinoal (4D) MIP Images to Account for Target Motion in SBRT Lung Treatment? Med Phys 2011. [DOI: 10.1118/1.3612474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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528
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Fourkal E, Veltchev I, Lin M, Ma C. SU-E-T-677: Tissue Inhomogeneity in Hadron Therapy. Med Phys 2011. [DOI: 10.1118/1.3612639] [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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529
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Liu T, Yin Y, Bai T, Chen J, Lu J, Sun T, Gao M, Ma C. SU-E-T-821: Comparison of Intensity-Modulated Arc Therapy and Intensity-Modulated Radiotherapy Plans for Nasopharyngeal Carcinoma Simultaneously Integrated Boost Radiation Therapy. Med Phys 2011. [DOI: 10.1118/1.3612785] [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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530
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Fan J, Hayes S, Jin L, Wang L, Yang J, Ma C. SU-E-T-876: Comparison of Dose Distributions for Plans Optimized by Using Monte Carlo and Ray-Tracing Algorithms for the Treatment of Lung Tumors with CyberKnife. Med Phys 2011. [DOI: 10.1118/1.3612840] [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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531
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Myint KZ, Ma C, Wang L, Xie XQ. Fragment-similarity-based QSAR (FS-QSAR) algorithm for ligand biological activity predictions. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2011; 22:385-410. [PMID: 21598200 DOI: 10.1080/1062936x.2011.569943] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Quantitative structure-activity relationship (QSAR) studies are useful computational tools often used in drug discovery research and in many scientific disciplines. In this study, a robust fragment-similarity-based QSAR (FS-QSAR) algorithm was developed to correlate structures with biological activities by integrating fragment-based drug design concept and a multiple linear regression method. Similarity between any pair of training and testing fragments was determined by calculating the difference of lowest or highest eigenvalues of the chemistry space BCUT matrices of corresponding fragments. In addition to the BCUT-similarity function, molecular fingerprint Tanimoto coefficient (Tc) similarity function was also used as an alternative for comparison. For validation studies, the FS-QSAR algorithm was applied to several case studies, including a dataset of COX2 inhibitors and a dataset of cannabinoid CB2 triaryl bis-sulfone antagonist analogues, to build predictive models achieving average coefficient of determination (r(2)) of 0.62 and 0.68, respectively. The developed FS-QSAR method is proved to give more accurate predictions than the traditional and one-nearest-neighbour QSAR methods and can be a useful tool in the fragment-based drug discovery for ligand activity prediction.
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532
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Chen L, Mu Z, Chen X, Cvetkovic D, Pollack A, Ma C. WE-E-220-07: Therapeutic Effects of Pulsed Focused Ultrasound Enhancement of Docetaxel Combined with Radiotherapy on Prostate Cancer In Vivo. Med Phys 2011. [DOI: 10.1118/1.3613402] [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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533
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Ding M, Heard D, Ma C. SU-E-J-66: Improvement in SRS Commission and Patient-Specific Quality Assurance. Med Phys 2011. [DOI: 10.1118/1.3611834] [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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534
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Koren S, Lin M, Veltchev I, Ma C. SU-E-T-212: Measurement Comparison and Monte Carlo Analysis for Rapid Arc Delivery Verification Using ArcCheck Dosimetry System. Med Phys 2011. [DOI: 10.1118/1.3612162] [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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535
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Lin M, Li J, Wang L, Ma C. MO-D-BRB-04: EPID-Based 4D Patient Dose Verification for Lung SBRT Treatment. Med Phys 2011. [DOI: 10.1118/1.3612909] [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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536
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Hossain M, Price R, Tafo AG, Veltchev I, Lin T, Wang L, Ma C. SU-E-T-69: A Broad Implementation of Treatment Planning System QA. Med Phys 2011. [DOI: 10.1118/1.3612020] [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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537
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Jin L, Fan J, Wang L, Price R, Ma C. SU-E-T-552: Dosimetry Investigation of a PinPoint Ion Chamber for SRS Commissioning and Treatment Verification. Med Phys 2011. [DOI: 10.1118/1.3612514] [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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538
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Lin T, Hossain M, Ma C. SU-E-T-477: Multileaf Collimator Quality Assurance for Volumetric Modulated Arc Therapy. Med Phys 2011. [DOI: 10.1118/1.3612431] [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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539
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Fourkal E, Fan J, Hayes S, Price R, Ma C. SU-E-T-758: Cyberknife Treatment of Endometrial Cervical Cancer. Med Phys 2011. [DOI: 10.1118/1.3612722] [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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540
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Koren S, Price R, Tafo AG, Veltchev I, Fourkal E, Ma C. SU-E-T-219: Ion Chamber Dosimetry Modification under Strong Magnetic Field Conditions; Air and Liquid Filled Chambers Study. Med Phys 2011. [DOI: 10.1118/1.3612169] [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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541
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Liu H, Xue J, Chen X, Lin M, Koren S, Dong Z, Chen L, Ma C. SU-E-T-158: An End-To-End Quality Assurance Procedure for Advanced Radiation Therapy. Med Phys 2011. [DOI: 10.1118/1.3612108] [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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542
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Spencer EC, Ross NL, Parker SF, Woodfield BF, Boerio-Goates J, Smith SJ, Olsen RE, Kolesnikov AI, Navrotsky A, Ma C. Determination of the magnetic contribution to the heat capacity of cobalt oxide nanoparticles and the thermodynamic properties of the hydration layers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:205303. [PMID: 21540512 DOI: 10.1088/0953-8984/23/20/205303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We present low temperature (11 K) inelastic neutron scattering (INS) data on four hydrated nanoparticle systems: 10 nm CoO·0.10H(2)O (1), 16 nm Co(3)O(4)·0.40H(2)O (2), 25 nm Co(3)O(4)·0.30H(2)O (3) and 40 nm Co(3)O(4)·0.026H(2)O (4). The vibrational densities of states were obtained for all samples and from these the isochoric heat capacity and vibrational energy for the hydration layers confined to the surfaces of these nanoparticle systems have been elucidated. The results show that water on the surface of CoO nanoparticles is more tightly bound than water confined to the surface of Co(3)O(4), and this is reflected in the reduced heat capacity and vibrational entropy for water on CoO relative to water on Co(3)O(4) nanoparticles. This supports the trend, seen previously, for water to be more tightly bound in materials with higher surface energies. The INS spectra for the antiferromagnetic Co(3)O(4) particles (2-4) also show sharp and intense magnetic excitation peaks at 5 meV, and from this the magnetic contribution to the heat capacity of Co(3)O(4) nanoparticles has been calculated; this represents the first example of use of INS data for determining the magnetic contribution to the heat capacity of any magnetic nanoparticle system.
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543
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Leblanc J, Zhang X, McKee D, Wang ZB, Li R, Ma C, Sun QY, Liu XJ. The small GTPase Cdc42 promotes membrane protrusion during polar body emission via ARP2-nucleated actin polymerization. Mol Hum Reprod 2011; 17:305-16. [PMID: 21511720 DOI: 10.1093/molehr/gar026] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Polar body emission is a specialized cell division throughout the animal kingdom, serving to reduce chromosome ploidy while preserving the egg cytoplasm. Critical to polar body emission are the asymmetric positioning of the meiotic spindle prior to anaphase, with one pole attached to the oocyte cortex, and the simultaneous membrane protrusion during subsequent cytokinesis. We have shown that, during Xenopus oocyte maturation, the small GTPase Cdc42 promotes membrane protrusion while a classical RhoA contractile ring forms and constricts at the base of the protrusion. We report here that treating oocytes with low concentrations of nocodazole diminished the size of metaphase I spindles and prevented polar body emission, and yet an active Cdc42 cap of correspondingly diminished size still developed, on time, atop of the spindle pole. Conversely, treating oocytes with low concentrations of taxol resulted in a spindle with multiple poles attached to the cortex, but still each of these poles were associated with activated cortical Cdc42 at the appropriate time. Therefore, the asymmetric positioning of the meiotic spindle with one pole anchored to the cortex is a prerequisite for Cdc42 activation. Furthermore, we demonstrated that the Cdc42-regulated F-actin nucleator ARP2/3 complex was similarly localized at the cortex of the protruding polar body membrane, suggesting that Cdc42 promotes membrane protrusion through an F-actin meshwork mechanism. Finally, we demonstrated that Cdc42 and RhoA formed similarly complementary activity zones during egg activation and that inhibition of Cdc42 prevented second polar body emission. Therefore, Cdc42 activation likely promotes membrane protrusion during polar body emission in widespread systems.
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544
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Kalmokoff M, Waddington LM, Thomas M, Liang KL, Ma C, Topp E, Dandurand UD, Letellier A, Matias F, Brooks SPJ. Continuous feeding of antimicrobial growth promoters to commercial swine during the growing/finishing phase does not modify faecal community erythromycin resistance or community structure. J Appl Microbiol 2011; 110:1414-25. [PMID: 21395944 DOI: 10.1111/j.1365-2672.2011.04992.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIMS To investigate the effect of continuous feeding of antimicrobial growth promoters (tylosin or virginiamycin) on the swine faecal community. METHODS AND RESULTS The study consisted of two separate on-farm feeding trials. Swine were fed rations containing tylosin (44 or 88 mg kg(-1) of feed) or virginiamycin (11 or 22 mg kg(-1) of feed) continuously over the growing/finishing phases. The temporal impact of continuous antimicrobial feeding on the faecal community was assessed and compared to nondosed control animals through anaerobic cultivation, the analysis of community 16S rRNA gene libraries and faecal volatile fatty acid content. Feeding either antimicrobial had no detectable effect on the faecal community. CONCLUSIONS Erythromycin methylase genes encoding resistance to the macrolide-lincosamide-streptogramin B (MLS(B) ) antimicrobials are present at a high level within the faecal community of intensively raised swine. Continuous antimicrobial feeding over the entire growing/finishing phase had no effect on community erm-methylase gene copy numbers or faecal community structure. SIGNIFICANCE AND IMPACT OF THE STUDY Antimicrobial growth promoters are believed to function by altering gut bacterial communities. However, widespread MLS(B) resistance within the faecal community of intensively raised swine likely negates any potential effects that these antimicrobials might have on altering the faecal community. These findings suggest that if AGP-mediated alterations to gut communities are an important mechanism for growth promotion, it is unlikely that these would be associated with the colonic community.
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545
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Ma C, Li LF, Chen X. Expression of metallothionein-I and II in skin ageing and its association with skin proliferation. Br J Dermatol 2011; 164:479-82. [DOI: 10.1111/j.1365-2133.2010.10117.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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546
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Yang HX, Tian HF, Song YJ, Qin YB, Zhao YG, Ma C, Li JQ. Polar nanodomains and giant converse magnetoelectric effect in charge-ordered Fe2OBO3. PHYSICAL REVIEW LETTERS 2011; 106:016406. [PMID: 21231761 DOI: 10.1103/physrevlett.106.016406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Indexed: 05/30/2023]
Abstract
The magnetoelectric coupling and polar nanodomains in the charge-ordered Fe2OBO3 have been extensively studied from room temperature down to 100 K. In situ TEM investigations demonstrate that the charge-ordering transition characterized by an incommensurate modulation could evidently result in remarkable polar nanodomains at low temperatures. This kind of nanodomain could play a critical role in triggering a high dielectric constant and notable dielectric dispersion as observed in Fe2OBO3. Moreover, measurements of the magnetoelectric coupling under electrical field demonstrate the existence of giant electrically induced changes in magnetization around the magnetic transition.
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547
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Tan X, Frederick J, Ma C, Jo W, Rödel J. Can an electric field induce an antiferroelectric phase out of a ferroelectric phase? PHYSICAL REVIEW LETTERS 2010; 105:255702. [PMID: 21231602 DOI: 10.1103/physrevlett.105.255702] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Indexed: 05/30/2023]
Abstract
It has been widely accepted that electric fields favor the ferroelectric phase with parallel electric dipoles over the antiferroelectric phase. With detailed measurements in polycrystalline ceramics of Pb(0.99)Nb(0.02[(Zr(0.57)Sn(0.43)(1-y)Ti(y)](0.98)O(3), we demonstrate in this Letter that electric fields can induce an antiferroelectric phase out of a ferroelectric phase, i.e., trigger an apparently unlikely ferroelectric-to-antiferroelectric phase transition. We suggest that it is caused by the volume contraction from the converse piezoelectric effect at the coercive field with a reversed polarity.
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548
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Shi L, Lei D, Ma C, Xu F, Li Y, Wang Y, Cong N, Liu D, Pan XL. Clinicopathological implications of tumour-associated macrophages and vascularization in sinonasal melanoma. J Int Med Res 2010; 38:1276-86. [PMID: 20926000 DOI: 10.1177/147323001003800409] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
This study investigated tumour-associated macrophages (TAMs) and their effects on tumour vascularization in sinonasal melanoma (SNM). Data on 45 patients with SNM undergoing surgery were reviewed retrospectively. Tumour sections were analysed immunohistochemically for TAMs, microvessels, lymph vessels, and vasculogenic mimicry in both intra- and peritumoural areas. The density of intratumoural TAMs was associated with tumour thickness and with overall survival in SNM stages I and II but there were no correlations between micro- or lymph vessel density and TAM infiltration. Greater TAM infiltration was observed in tumour tissues with vasculogenic mimicry although this was not statistically significant. These data suggest that high intratumoural TAM infiltration is associated with tumour aggressiveness and a poor prognosis for SNM, and that activation of macrophages can be polarized by different micro-environments. TAMs could be potential prognostic indicators for patients with SNM.
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549
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Piwnica-Worms H, Ma C, Cai S, Ryan C, Guo Z, Li S, Ellis M. 243 Targeting the Chk1/Cdc25A pathway in p53-deficient tumors. EJC Suppl 2010. [DOI: 10.1016/s1359-6349(10)71948-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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550
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Lin M, Li J, Koren S, Lin T, Wang L, Ma C. A Practical Monte Carlo Based Patient Dose Verification Tool for RapidArc Treatment. Int J Radiat Oncol Biol Phys 2010. [DOI: 10.1016/j.ijrobp.2010.07.1701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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