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Bao H, She R, Liu T, Zhang Y, Peng KS, Luo D, Yue Z, Ding Y, Hu Y, Liu W, Zhai L. Effects of pig antibacterial peptides on growth performance and intestine mucosal immune of broiler chickens. Poult Sci 2009; 88:291-7. [PMID: 19151342 DOI: 10.3382/ps.2008-00330] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Currently, substitutions for antibiotic growth promoters in animals are attracting interest. This study investigated the effects of pig antibacterial peptides (PABP) on growth performance and small intestine mucosal immune responses in broilers. Three hundred 1-d-old Arbor Acre male broiler chickens were randomly allocated to 5 groups with 60 birds per group. The groups were control group; PABP administered in drinking water at 20 and 30 mg/L of water; or PABP supplemented in feed at 150 and 200 mg/kg of diet. The birds were fed a corn-soybean based diet for 6 wk. Chickens were weighed weekly and killed after 42 d of feeding, and growth performance was measured. Samples of the duodenum and jejunum were collected. The villus height, mucosa thickness, alkaline phosphatase activity, and numbers of secreting IgA and goblet cells were evaluated. The PABP-treated groups had greater BW and average daily gain, greater height of villus and thickness of gut mucosa, greater activity of alkaline phosphatase, higher ratio of secreting IgA, and a greater number of goblet cells compared with the control group (P<0.05). In conclusion, PABP can improve the growth performance, increase the intestinal ability to absorb nutrients, and improve the mucosal immunity of the intestine.
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Liu W. Effects of Bt transgenic crops on soil ecosystems: a review of a ten-year research in China. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11703-009-0027-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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1228
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Dai R, Li Z, Li F, Liu D, Liu W, Liu G, He S, Tan M, Lin R, Liu Y, Zhu X. Severe infection of adult dogs with helminths in Hunan Province, China poses significant public health concerns. Vet Parasitol 2009; 160:348-50. [DOI: 10.1016/j.vetpar.2008.11.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2008] [Revised: 10/26/2008] [Accepted: 11/03/2008] [Indexed: 11/27/2022]
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He Y, Hua Y, Song S, Liu W, Keep RF, Xi G. Induction of autophagy in rat hippocampus and cultured neurons by iron. CEREBRAL HEMORRHAGE 2009; 105:29-32. [DOI: 10.1007/978-3-211-09469-3_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Bo H, Wei XQ, Dong H, Zhang Y, Lv P, Liu W, Koutoulaki A, Gao XM. Elevated expression of transmembrane IL-15 in immune cells correlates with the development of murine lupus: a potential target for immunotherapy against SLE. Scand J Immunol 2009; 69:119-29. [PMID: 19170964 DOI: 10.1111/j.1365-3083.2008.02197.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Presentation in trans by the Interleukin-15 receptor alpha chain (IL-15Ralpha) has been suggested as the main mechanism for IL-15 anchoring to the cell surface, but it is also evident that IL-15 can exist as a transmembrane protein. We herein demonstrate that replacement of the first 41 residues of human IL-15 (hIL-15) with Igkappa chain leader sequence resulted in secretion of most of the recombinant hIL-15 expressed in transfectant cells, thus identifying the transmembrane region of IL-15. A fusion protein (hIL-15Ralpha-Fc) between the extracellular domain of hIL-15Ralpha and the Fc fragment of IgG1 was prepared and shown to be able to bind with transmembrane IL-15 (tmIL-15). The level of tmIL-15 expression in macrophages, activated T cells and B cells from 6-month-old BXSB male mice, an animal model for systemic lupus erythematosus (SLE), was significantly increased compared with that from BXSB females or young males. In addition, hIL-15Ralpha-Fc was able to block the T cell stimulating and anti-apoptotic effect of the tmIL-15-positive BXSB macrophages in vitro. Intravenous administration of hIL-15Ralpha-Fc reduced the titre of autoantibodies against dsDNA and also proteinuria in aged BXSB males, implying that neutralization of IL-15 activity in vivo may be an effective way of treating SLE.
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Soh CB, Liu W, Chua SJ, Teng JH, Tan RJN, Ang SS. Novel tunable phosphor-free white III-nitride light emitting diodes based on indium rich InGaN nanostructures. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/pssc.200880782] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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1232
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Yoo T, Zhou Y, Ensell M, Glickstein J, Kermany M, Cai Q, Cai C, Kim J, Kim P, Liu W. Induction of Specific Th1 Responses and Suppression of IgE Antibody Formation and Airway Eosinophilia by Vaccination with Plasmid DNA Encoding Bla g 1. J Allergy Clin Immunol 2009. [DOI: 10.1016/j.jaci.2008.12.547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Liu W. Correlation between specific fine root length and mycorrhizal colonization of maize in different soil types. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11703-009-0004-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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1234
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Liu W, Dechev N, Lee SW, Foulds IG, Parameswaran A, Burke R, Park EJ. Development of a magnetic Single Cell Micro Array. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2008:3170-3. [PMID: 19163380 DOI: 10.1109/iembs.2008.4649877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Experiments using single cells are valuable for revealing individual cell behaviour, which is of interest to many biomedical researchers. In such experiments, various types of devices capable of aligning cells into organized arrays are often used. In this paper, we present a novel Single Cell Micro Array device that makes use of magnetic forces. Prototypes of this device have been fabricated, and successfully tested using Jurkat cells that have been labelled with nano-magnetic particles. Experimental results show that the prototypes are effective on capturing and placing the labelled cells in an array.
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Wang G, He Y, Hu S, Liu W, Liu G. Molecular characterization and tissue transcription
profile analyses of three novel pig genes - NDP,
CLN3 and NCF1. JOURNAL OF ANIMAL AND FEED SCIENCES 2009. [DOI: 10.22358/jafs/66368/2009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Sun C, Sui T, Liu W, Yang R. Gastrointestinal bleeding attributable to a small intestine angioleiomyoma in a patient with haemophilia A. Haemophilia 2009; 15:355-6. [PMID: 19149860 DOI: 10.1111/j.1365-2516.2008.01913.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Drusano G, Liu W, Brown D, Rice L, Louie A. Impact of Short‐Course Quinolone Therapy on Susceptible and Resistant Populations ofStaphylococcus aureus. J Infect Dis 2009; 199:219-26. [DOI: 10.1086/595739] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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1238
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Almagableh AM, Mantena PR, Alostaz A, Liu W, Drzal LT. Effects of bromination on the viscoelastic response of vinyl ester nanocomposites. EXPRESS POLYM LETT 2009. [DOI: 10.3144/expresspolymlett.2009.90] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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1239
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Liu W, Zhao YH, Li Y, Lavernia EJ, Jiang Q. A reversible switch for hydrogen adsorption and desorption: electric fields. Phys Chem Chem Phys 2009; 11:9233-40. [DOI: 10.1039/b907591g] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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1240
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Liu W, Mukherjee M, Tsaur Y, Kim SH, Liu H, Natarajan P, Agah A. Development and feasibility study of a sensory-enhanced robot-aided motor training in stroke rehabilitation. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2009:5965-5968. [PMID: 19964884 DOI: 10.1109/iembs.2009.5334526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Functional impairment of the upper limb is a major challenge faced by many stroke survivors. The present study aimed at developing a novel sensory-enhanced robot-aided motor training program and testing its feasibility in stroke rehabilitation. A specially designed robot handle was developed as an attachment to the Inmotion2 robotic system. This handle provided sensory stimulation through pins connected to small servo motors inside the handle. Vibration of the pins was activated during motor training once pressure on the handle reached a certain threshold indicating an active motion of the study subject. Nine chronic stroke survivors were randomly assigned to either a sensory-enhanced robot-aided motor training group (SERMT) or robot-aided motor training only group (RMT). All participants underwent a 6-week motor training program, performing target reaching movements with the specialized handle with or without vibration stimulation during training. Motor Status (MS) scores were measured for functional outcome prior to and after training. The results showed significant improvement in the total MS scores after training in both experimental groups. However, MS sub-scores for the shoulder/elbow and the wrist/hand increased significantly only in the SERMT group (p<0.05). Future studies are required to confirm these preliminary findings.
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Murakami M, Bai XJ, Shi WS, Wang WM, Liu W, Dong YJ. 45 DEVELOPMENT OF BOVINE NUCLEAR TRANSFER EMBRYOS DERIVED FROM ADULT MARROW STROMAL CELLS AND FETAL MUSCLE CELLS. Reprod Fertil Dev 2009. [DOI: 10.1071/rdv21n1ab45] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The use of less differentiated cells, such as marrow stromal cells (MSCs), as the nuclear donor may increase the efficiencies of somatic cell cloning in cattle. Healthy offspring was produced from bovine MSCs (Kato et al. 2004 Biol. Reprod. 70, 415–418); however, there is little information that directly compared the post-implantation survival among the clones originated from MSCs and other somatic cells. The objective of this study was to evaluate the developmental potential in vitro and in vivo of bovine NT embryos derived from adult MSCs and fetal muscle cells (FMCs). Primary cell populations of MSCs and FMCs were obtained from the femurs of 8- and 12-months-old Holstein cows (MSC1 and MSC2 groups, respectively) and a Holstein fetus at 8 months of gestation (FMC group), respectively. They were used as donor cells for the NT procedure (Murakami et al. 2005 Cloning Stem Cells 7, 77–81) at passages 1 to 3. Briefly, oocytes collected from cow ovaries were enucleated at 20 h post-in vitro maturation (IVM), and the donor cell was placed into the perivitelline space. The couplets were fused electrically, activated (10 μg mL–1 cycloheximide; 4 h), and cultured in CR1aa medium. Development in vitro of these embryos is summarized in Table 1. Data were analyzed by ANOVA. The fusion rates were higher in the MSC groups than in the FMC group. The rate of cleaved embryos was significantly lower (P < 0.05) in the MSC1 group than in the other groups. However, there were no significant differences among the groups in the rates of development into morulae/blastocysts on Day 6. A total of 8 and 3 fresh good quality Day 6 embryos in the MSC1 and FMC groups, respectively, were nonsurgically transferred to 6 naturally cycling Holstein females 6 days after estrus (3 recipients/group, 1–3 embryos/female). On Day 30 of gestation, none of the recipients were pregnant in the FMC group, while 2 recipients in the MSC1 group were diagnosed as pregnant via ultrasonography; they remained pregnant on Day 80 of gestation. In addition, a total of 4 Day 7 embryos cryopreserved in 1.8 m ethylene glycol plus 0.05 m trehalose were directly transferred to 4 synchronized recipients after thawing (1 embryo/female) in the MSC1 group. Of those, 2 females were pregnant on day 30 of gestation. These results indicate that the developmental potential in vitro of bovine NT embryos derived from adult MSCs was comparable to that of the embryos derived from fetal muscle cells, and that pregnancies were produced after transfer of the fresh and frozen–thawed NT embryos derived from the MSC, but the sample size was small. Further studies with more replicates are needed to evaluate viability in vivo of these cloned embryos for comparative purposes.
Table 1.Development in vitro of bovine NT embryos derived from different cell types
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Liu W, Wang P, Li Z, Xu W, Dai L, Wang K, Zhang J. Evaluation of Tumour-Associated Antigen (TAA) Miniarray in Immunodiagnosis of Colon Cancer. Scand J Immunol 2009; 69:57-63. [DOI: 10.1111/j.1365-3083.2008.02195.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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1243
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Shan ZY, Chen YY, Teng WP, Yu XH, Li CY, Zhou WW, Gao B, Zhou JR, Ding B, Ma Y, Wu Y, Liu Q, Xu H, Liu W, Li J, Wang WW, Li YB, Fan CL, Wang H, Guo R, Zhang HM. A study for maternal thyroid hormone deficiency during the first half of pregnancy in China. Eur J Clin Invest 2009; 39:37-42. [PMID: 19087128 DOI: 10.1111/j.1365-2362.2008.02055.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Maternal thyroid hormone deficiency is the most common disorder of thyroid function during pregnancy and can influence the outcome for mother and foetus. The purpose of this study was to investigate the prevalence of thyroid hormone deficiency during the first half of pregnancy in iodine sufficient areas of China. MATERIALS AND METHODS Four thousand eight hundred pregnant women from 10 hospitals during the first 20 weeks of gestation were enrolled in this study. All sera obtained from pregnant women were measured for thyrotropin, free thyroxine and thyroid peroxidase antibody. Screening for thyroid hormone deficiency was performed on pregnant women using gestational age-specific reference intervals or non-pregnant population reference intervals. RESULTS With gestational age-specific reference intervals as the criterion, the prevalence of subclinical hypothyroidism at 4, 8, 12,16 and 20 weeks of gestation was 4.59%, 6.15%, 4.68%, 4.53% and 5.96%, respectively, and the prevalence of hypothyroxinaemia was 3.69%, 1.11%, 2.92%, 1.29% and 2.29%, respectively. Different prevalence was obtained when non-pregnant population reference intervals was used as the criterion. If non-pregnant population reference intervals were used, the percentage of potentially misclassified cases of subclinical hypothyroidism were 0.18%, 2.85%, 4.1%, 3.24%, and 3.21%, respectively, and 3.45%, 0.66%, 2.34%, 1.29%, and 1.83%, respectively, in potentially misclassified cases of hypothyroxinaemia. CONCLUSIONS The percentage of potentially misclassified cases of subclinical hypothyroidism and hypothyroxinaemia in pregnant women decreased by using the gestational age-specific reference intervals as a diagnostic criteria during the first half of pregnancy.
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Tao CJ, Hu JY, Li JZ, Zheng SS, Liu W, Li CJ. Multi-residue determination of pesticides in vegetables by gas chromatography/ion trap mass spectrometry. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 82:111-115. [PMID: 18795216 DOI: 10.1007/s00128-008-9528-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Accepted: 08/22/2008] [Indexed: 05/26/2023]
Abstract
To monitor possible contamination of edible vegetables by common pesticides, an analytical method using gas chromatography combined with ion trap spectrometry (GC-IT/MS) was developed to measure simultaneously up to 39 pesticide residues, belonging to organophosphors, organochlorines, pyrethroids or carbamates classes, left on four kinds of popular vegetables. The procedure entails addition of acetone, dichloromethane, and sodium chloride to a small amount of vegetable, then the mixture was shaken intensively and centrifuged for phase separation. An aliquot of the organic layer was cleanup using solid-phase extraction (SPE) cartridges filled with graphitized carbon black (GCB) in combination with acidic aluminum oxide. Gas chromatography with ion trap mass spectrometer was then used for qualitative and quantitative determination of the pesticides. The GCB combination with acidic aluminum oxide was found more suitable than florisil, aluminum oxide and silicon dioxide for sample cleanup with recoveries above 70% for most pesticides in removing the majority of co-extracted matrices. Variation coefficients of the repeatability typically smaller than 20% have been achieved for a wide range of the investigated pesticides. A set of critical instrument parameters for the GC-IT/MS Varian system in the MS mode was established. Based on optimization work conducted in this study, the 39 pesticides were separated successively with the limits of detection between 0.02 and 0.1 mg/kg.
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Li ZL, Liu W, Chen XF, Shang WL. Research on the application of horseradish peroxidase and hydrogen peroxide to the oil removal of oily water. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2009; 59:1751-1758. [PMID: 19448310 DOI: 10.2166/wst.2009.177] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Horseradish peroxidase (HRP) has the advantages of low cost, obtaining convenience, broad substrate specificity, etc, so it may be a suitable kind of enzyme to remove dilute emulsified oil and dissolved oil from water. The effect factors of the oil removal using HRP, such as pH, concentrations of HRP and H2O2, additives, Fe2+ ion, temperature and reaction time were researched. When the initial oil concentration was 120 mg/L, the remaining oil concentrations of the synthetic oily water and an actual oily wastewater reached 24.83 mg/L and 21.30 mg/L, respectively. The treatment of oily water using HRP and H2O2 is feasible. It has good application prospects.
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Ma XQ, Cao Y, Wang R, Yan X, Zhao Y, Zou D, Wallander MA, Johansson S, Liu W, Gu Z, Zhao J, He J. Prevalence of, and factors associated with, gastroesophageal reflux disease: a population-based study in Shanghai, China. Dis Esophagus 2008; 22:317-22. [PMID: 19207545 DOI: 10.1111/j.1442-2050.2008.00904.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The prevalence of gastroesophageal reflux disease (GERD) in China is lower than that in the Western countries, but appears to be increasing. The aim of this pilot study was to evaluate the prevalence of GERD in Shanghai, China, and to explore which population characteristics where associated with GERD. A sample of 1200 adult inhabitants of Shanghai, selected using randomized, stratified, multi-stage sampling, completed Mandarin translations of the Reflux Disease Questionnaire and GERD Impact Scale. Potential risk factors for GERD were examined by nested case-control analysis, using Cochran-Armitage trend testing and logistic regression analysis. The response rate was 86.2%; 919 responses were suitable for analysis. The prevalence of GERD, defined as heartburn and/or regurgitation of any frequency during the previous week, was 6.2% in Shanghai. Obesity and urban dwelling were associated with GERD (odds ratio 3.4, 95% confidence interval 1.3-9.3; and odds ratio 3.6, 95% confidence interval 1.2-10.4, respectively). The prevalence of GERD in Shanghai agreed with previous Chinese studies. GERD in Shanghai was associated with obesity and residency in an urban environment.
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Dong Y, Liu W, Gao Y, Wu R, Zhang Y, Wang H, Wei B. Neural Stem Cell Transplantation Rescues Rectum Function in the Aganglionic Rat. Transplant Proc 2008; 40:3646-52. [DOI: 10.1016/j.transproceed.2008.06.107] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Revised: 06/08/2008] [Accepted: 06/18/2008] [Indexed: 11/30/2022]
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1248
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Hayter A, Kim J, Liu W. Critical point computations for one-sided and two-sided pairwise comparisons of three treatment means. Comput Stat Data Anal 2008. [DOI: 10.1016/j.csda.2008.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Liu W, Wiersma RD, Mao W, Luxton G, Xing L. Real-time 3D internal marker tracking during arc radiotherapy by the use of combined MV-kV imaging. Phys Med Biol 2008; 53:7197-213. [PMID: 19043177 DOI: 10.1088/0031-9155/53/24/013] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
To minimize the adverse dosimetric effect caused by tumor motion, it is desirable to have real-time knowledge of the tumor position throughout the beam delivery process. A promising technique to realize the real-time image guided scheme in external beam radiation therapy is through the combined use of MV and onboard kV beam imaging. The success of this MV-kV triangulation approach for fixed-gantry radiation therapy has been demonstrated. With the increasing acceptance of modern arc radiotherapy in the clinics, a timely and clinically important question is whether the image guidance strategy can be extended to arc therapy to provide the urgently needed real-time tumor motion information. While conceptually feasible, there are a number of theoretical and practical issues specific to the arc delivery that need to be resolved before clinical implementation. The purpose of this work is to establish a robust procedure of system calibration for combined MV and kV imaging for internal marker tracking during arc delivery and to demonstrate the feasibility and accuracy of the technique. A commercially available LINAC equipped with an onboard kV imager and electronic portal imaging device (EPID) was used for the study. A custom built phantom with multiple ball bearings was used to calibrate the stereoscopic MV-kV imaging system to provide the transformation parameters from imaging pixels to 3D world coordinates. The accuracy of the fiducial tracking system was examined using a 4D motion phantom capable of moving in accordance with a pre-programmed trajectory. Overall, spatial accuracy of MV-kV fiducial tracking during the arc delivery process for normal adult breathing amplitude and period was found to be better than 1 mm. For fast motion, the results depended on the imaging frame rates. The RMS error ranged from approximately 0.5 mm for the normal adult breathing pattern to approximately 1.5 mm for more extreme cases with a low imaging frame rate of 3.4 Hz. In general, highly accurate real-time tracking of implanted markers using hybrid MV-kV imaging is achievable and the technique should be useful to improve the beam targeting accuracy of arc therapy.
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Liu W, Shen G, Shi Z, Shen F, Zheng X, Wen L, Yang X. Brain tumour stem cells and neural stem cells: still explored by the same approach? J Int Med Res 2008; 36:890-5. [PMID: 18831881 DOI: 10.1177/147323000803600504] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Brain tumour stem cells (BTSCs) are chiefly responsible for the in vivo long-term growth and recurrence of malignant gliomas and may be a potential treatment target. They resemble neural stem cells (NSCs), so their self-renewal and differentiation are currently investigated by the same methods used to study NSCs. There are, however, essential differences between these cell types: in many cases the marker expression pattern of BTSCs does not match the CD133(+)/NSE(-)/FAP(-) pattern of NSCs; BTSC tumourigenicity is independent of marker expression; and while attachment, serum-containing medium and withdrawal of mitogens (epidermal growth factor [EGF] and basic fibroblast growth factor [bFGF]) are essential to induce NSCs to differentiate, they do not affect BTSC tumourigenicity. Evidence implies that research on the renewal and differentiation of BTSCs should be orientated towards tumourigenicity and is essentially a pharmaceutical problem. Such an approach may contribute to the development of an accurate definition of BTSCs and to the search for selective differentiation-inducing drugs for BTSCs.
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