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Li QY, Zhang SX, Liu ZJ, Tan LW, Qiu MG, Li K, Cui GY, Guo YL, Yang XP, Zhang WG, Chen XH, Chen JH, Ding SY, Chen W, You J, Wang YS, Deng JH, Tang ZS. The pre-styloid compartment of the parapharyngeal space: a three-dimensional digitized model based on the Chinese Visible Human. Surg Radiol Anat 2005; 26:411-6. [PMID: 15300412 DOI: 10.1007/s00276-004-0252-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
To build a digitized visible model of the parapharyngeal space of the Chinese Visible Human and to provide a sectional anatomic basis for radiological and clinical diagnosis of the parapharyngeal space, sectional anatomy data of the parapharyngeal space were selected from the Chinese Visible Human male and female to compare with MR imaging findings in the axial planes. From these data the parapharyngeal space and surrounding structures were segmented. They were then reconstructed in three dimensions on PC. In the axial planes of the sectional anatomy and MR imaging, the shape, content and relations of the parapharyngeal space were clearly displayed and the dominant plane for showing the parapharyngeal space was elicited. The three-dimensional reconstructed images displayed perfectly the anatomic relationships of the parapharyngeal space, parotid, muscles, mandible and vessels. All reconstructed structures can be displayed singly, in groups or as a whole; any diameter or angle of the reconstructed structures can be easily measured. The Chinese Visible Human male and female data set can provide complete and accurate data. The digitized model of the parapharyngeal space and its surroundings offers unique insights into the complex anatomy of the area, providing morphologic data for imaging diagnosis and surgery of the parapharyngeal space.
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Zouboulis C, Chen W, Alestas T, Makrantonaki E, Seltmann H, Muller-Decker K. Sexual hormones utilize complex mechanisms to modulate sebocyte differentiation. Exp Dermatol 2005. [DOI: 10.1111/j.0906-6705.2005.0266l.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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1379
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Chen W, Li S, Srinivasan SR, Berenson GS. 56 LOW-DENSITY LIPOPROTEIN CHOLESTEROL INFLUENCES CAROTID ARTERY INTIMA-MEDIA THICKNESS, BUT NOT PULSE WAVE VELOCITY: THE BOGALUSA HEART STUDY. J Investig Med 2005. [DOI: 10.2310/6650.2005.00006.55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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1380
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Chen W, Li S, Srinivasan SR, Berenson GS. 274 TRACKING OF CARDIOVASCULAR RISK VARIABLES FROM CHILDHOOD TO ADULTHOOD IN BLACKS AND WHITES: THE BOGALUSA HEART STUDY. J Investig Med 2005. [DOI: 10.2310/6650.2005.00006.273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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1381
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Li S, Chen W, Srinivasan SR, Berenson GS. 279 CIGARETTE SMOKING EXACERBATES THE ADVERSE EFFECTS OF CARDIOVASCULAR RISK FACTORS ON CAROTID INTIMA-MEDIA THICKNESS: THE BOGALUSA HEART STUDY. J Investig Med 2005. [DOI: 10.2310/6650.2005.00006.278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Bhuiyan AR, Li S, Li H, Chen W, Srinivasan SR, Berenson GS. 74 DISTRIBUTION AND CORRELATES OF ARTERIAL COMPLIANCE MEASURES IN ASYMPTOMATIC YOUNG ADULTS: THE BOGALUSA HEART STUDY. J Investig Med 2005. [DOI: 10.2310/6650.2005.00006.73] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Kamolmatyakul S, Chen W, Yang S, Abe Y, Moroi R, Ashique AM, Li YP. IL-1alpha stimulates cathepsin K expression in osteoclasts via the tyrosine kinase-NF-kappaB pathway. J Dent Res 2004; 83:791-6. [PMID: 15381721 PMCID: PMC3966556 DOI: 10.1177/154405910408301011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Interleukin-1alpha (IL-1alpha) is a powerful activator of osteoclast cells. However, the underlying mechanism for this activation is unknown. In this study, we reveal that IL-1alpha up-regulates the expression of cathepsin K protein, a key protease in bone resorption, by five-fold. Northern blot analysis and promoter analysis show that this induction occurs at the transcriptional level, in a dose-responsive and time-dependent manner. No increase in expression occurs in the presence of either pyrrolidine dithiocarbamate (PDTC), a selective inhibitor of NF-kappaB, or Genistein, a protein tyrosine kinase inhibitor, suggesting that IL-1alpha up-regulation may be via the tyrosine kinase-NF-kappaB pathway to regulate cathepsin K expression. Antisense oligonucleotides to p65, but not the p50 subunit of NF-kappaB, suppress the IL-1alpha-induced expression of cathepsin K. We therefore conclude that IL-1alpha up-regulates cathepsin K gene expression at the transcription level, and this regulation may be via the tyrosine-kinase-NF-kappaB pathway.
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Li B, He X, Pang X, Zhang H, Chen J, Chen W. Elicitation of Both CD4+ and CD8+ T-Cell-Mediated Specific Immune Responses to HCA587 Protein by Autologous Dendritic Cells. Scand J Immunol 2004; 60:506-13. [PMID: 15541044 DOI: 10.1111/j.0300-9475.2004.01503.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We recently cloned a new member of cancer/testis antigen named HCA587, which was highly expressed in human hepatocellular carcinoma (HCC) tissues. To investigate it as a potential tumour-specific target for immunotherapy, the immunogenicity of this protein, especially the ability to induce specific cellular immune responses, was evaluated in the present study. As dendritic cells (DC) are the most potent antigen-presenting cells, DC-based vaccination has recently shown marked promise for the treatment of human malignancies by immunological intervention. Here, we demonstrate that autologous DC loaded with HCA587 protein could induce specific T-cell responses in healthy individuals by in vitro stimulations. Enzyme-linked immunospot analysis for interferon-gamma (IFN-gamma) secretion demonstrated HCA587-specific CD8(+) T cells in the antigen-stimulated peripheral blood lymphocytes, and the analysis of CD4(+) T cells by proliferation assay also showed antigen-specific reactivities in normal donors. Two-colour flow cytometric analysis of surface markers and intracellular cytokine expression demonstrated that HCA587-specific cytotoxic T lymphocytes exhibited a heterogeneous CD8(+)/CD56(+) expression, and a striking T-helper 1 cytokine bias (IFN-gamma(high)/IL-4(low)) was observed for both CD4(+) and CD8(+) HCA587-specific lymphocyte populations. We conclude that HCA587 is a potent immunogen that can induce CD4(+) and CD8(+) T-cell-mediated specific immune responses, and these findings propose HCA587 as a good candidate for the development of a therapeutic protein-based DC tumour vaccine for the treatment of HCC patients.
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Yang G, Chen IM, Chen W, Lin W. Kinematic Design of a Six-DOF Parallel-Kinematics Machine With Decoupled-Motion Architecture. IEEE T ROBOT 2004. [DOI: 10.1109/tro.2004.829485] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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1386
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Van Den Bogaert K, De Leenheer EMR, Chen W, Lee Y, Nürnberg P, Pennings RJE, Vanderstraeten K, Thys M, Cremers CWRJ, Smith RJH, Van Camp G. A fifth locus for otosclerosis, OTSC5, maps to chromosome 3q22-24. J Med Genet 2004; 41:450-3. [PMID: 15173231 PMCID: PMC1735823 DOI: 10.1136/jmg.2004.018671] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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1387
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Fujise O, Chen W, Rich S, Chen C. Clonal diversity and stability of subgingival Eikenella corrodens. J Clin Microbiol 2004; 42:2036-42. [PMID: 15131167 PMCID: PMC404643 DOI: 10.1128/jcm.42.5.2036-2042.2004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Eikenella corrodens is a commensal subgingival bacterium commonly found in both periodontally nondiseased and diseased subjects. The present study examined the clonal diversity and stability of subgingival E. corrodens over time. Ninety-five subjects were enrolled at the baseline examination, including 44 periodontally nondiseased subjects and 51 subjects with aggressive periodontitis. Twenty-two nondiseased subjects and 11 subjects with aggressive periodontitis were subsequently reexamined after an average interval of 14 months. Two subgingival plaque samples were obtained from each subject to determine the total cultivable bacteria. In addition, multiple E. corrodens isolates from each sample were recovered for clonal analysis by arbitrarily primed PCR. The mean numbers of distinct E. corrodens clones harbored by nondiseased subjects and subjects with aggressive periodontitis were 1.3 and 3.0, respectively. Thirty-nine percent of the nondiseased subjects and 63% of the subjects with aggressive periodontitis harbored multiple clones of E. corrodens. The numbers of distinct E. corrodens clones increased significantly (Mann-Whitney ranking test, P < 0.05) in sites from patients with aggressive periodontitis, in sites with pocket depths of 4 mm or greater, in sites with a clinical attachment loss of 2 mm or greater, and in sites coinfected with Porphyromonas gingivalis. Comparison of E. corrodens clones recovered at the baseline and those recovered at the follow-up examination showed that E. corrodens colonization was not stable. Thirty-eight of the 66 follow-up samples (58%) showed a complete change (including de novo colonization of the sites or complete elimination of the organism from the sites) of the subgingival E. corrodens clonal types between the baseline and the follow-up examinations. Our results suggest a complexity of subgingival microbiota not seen previously.
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Fu Y, Liu Z, Lin J, Jia Z, Chen W, Pan D, Lin Y, Zhu Y, Chen R, Xu A. HLA-DPB1, -DQB1 and -DRB1 allele frequencies in a Naxi population from South-West China. Hum Immunol 2004. [DOI: 10.1016/j.humimm.2004.08.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Liu Z, Lin J, Pan D, Chen W, Tao H, Xu A. HLA-DPB1 allele frequencies in a Pumi population from China. Hum Immunol 2004. [DOI: 10.1016/j.humimm.2004.08.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Urbina EM, Srinivasan SR, Kieltyka RL, Tang R, Bond MG, Chen W, Berenson GS. Correlates of carotid artery stiffness in young adults: The Bogalusa Heart Study. Atherosclerosis 2004; 176:157-64. [PMID: 15306189 DOI: 10.1016/j.atherosclerosis.2004.04.023] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2003] [Revised: 03/20/2004] [Accepted: 04/02/2004] [Indexed: 10/26/2022]
Abstract
Decreased arterial elasticity, an independent risk factor for cardiovascular (C-V) disease, is associated with C-V risk factors in middle-aged and older individuals. However, information is limited in this regard in young adults. This aspect was examined in a community-based sample of 516 black and white subjects aged 25-38 years (71% white, 39% male). The common carotid artery elasticity was measured from M-mode ultrasonography as Peterson's elastic modulus (Ep) and relative wall thickness-adjusted Young's elastic modulus (YEM). Blacks and males had higher Ep (P < 0.05); males had higher YEM (P < 0.0001); and blacks had higher wall thickness (P < 0.01). For the entire sample adjusted for race and gender both Ep and YEM correlated significantly (P < 0.05-0.0001) with age, BMI, waist, systolic and diastolic blood pressures, heart rate, product of heart rate and pulse pressure, triglycerides, total cholesterol to HDL cholesterol ratio, insulin and glucose. In a multivariate regression model that included hemodynamic variables, systolic blood pressure, product of heart rate and pulse pressure, age, triglycerides, BMI, and male gender (for YEM only) were independent correlates of Ep (R2 = 0.38) and YEM (R2 = 0.25). When the hemodynamic variables were excluded from the model, age, triglycerides, BMI, black race (Ep only), male gender, parental history of hypertension, HDL cholesterol (inverse association), and insulin (marginal significance) remained independent correlates of Ep (R2 = 0.20) and YEM (R2 = 16). Both Ep and YEM increased (P for trend P < 0.0001) with increasing number of independent continuous risk factors (defined as values above or below the age, race, and gender-specific extreme quintiles) that were retained in the regression models. The observed increasing arterial stiffness (or decreased elasticity) with increasing number of risk factors related to insulin resistance syndrome in free-living, asymptomatic young adults has important implications for prevention.
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Chen W, McBride W, Chen S, Hwang T, Lee K, Chen M. Cyclooxygenase-2 (COX-2) predicts poor survival of T4 nasopharyngeal cancer patients treated by radiation therapy: Clinical and in vitro studies. Int J Radiat Oncol Biol Phys 2004. [DOI: 10.1016/j.ijrobp.2004.07.422] [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]
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Chen W, Sauer J, Hara M. Morphology and deformation behavior of polymer blends made of poly(styrene-co-styrenesulfonic acid) and poly(methyl methacrylate-co-4-vinylpyridine). POLYMER 2004. [DOI: 10.1016/j.polymer.2004.08.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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1393
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Shen Z, Su Y, Chen J, Chen W. Effects of pentagastrin and IGF-1 on DNA synthesis
of rumen epithelial cells of dairy cow
and neonatal calf. JOURNAL OF ANIMAL AND FEED SCIENCES 2004. [DOI: 10.22358/jafs/73889/2004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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1394
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Agarwala S, Chen W, Cook TJ. Effect of Chlorpyrifos on Efflux Transporter Gene Expression and Function in Caco-2 Cells. Toxicol In Vitro 2004; 18:403-9. [PMID: 15130596 DOI: 10.1016/j.tiv.2003.12.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2003] [Accepted: 12/04/2003] [Indexed: 10/26/2022]
Abstract
The effect of chlorpyrifos (CPF) and its metabolite, chlorpyrifos-oxon (CPO), on multidrug resistance-1 (MDR1) gene expression and efflux transporter function in Caco-2 cells was determined. The effect of CPF and CPO on gene expression in Caco-2 cells was tested as a function of time using RT-PCR and competitive PCR (compPCR) techniques. The RT-PCR results depicted a maximal effect of CPF exposure on MDR1 expression at 8 h, which decreased at 24 h. Studies with CPO displayed an initial increase in expression at 4 h only. The compPCR assays were conducted with the CPF-treated group to quantify the changes in gene expression levels. The compPCR data confirmed and quantitated the results from the time-course study using semiquantitative RT-PCR. In addition to the gene expression studies, changes in efflux transporter function were investigated using Caco-2 cells grown on semipermeable membranes in Transwell plates. The permeability of verapamil was determined in cells treated for 8 h with CPF. Efflux ratios demonstrated that verapamil was effluxed at a higher rate from the CPF-treated cells as compared to the control group, confirming the inductive action of CPF on transporter function. These results suggest that CPF has the potential to modulate the bioavailability of drugs via changes in expression and function of membrane efflux transporters.
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Chen W, Li Q, Qiu L, Chen WM, Jiang SS. A Statistical Analysis of Crystal Developments for Bi-Superconductors. ACTA ACUST UNITED AC 2004. [DOI: 10.1023/b:josc.0000041791.64203.25] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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1396
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Chen W, Miller RA, Hebbe KA, Guron GK. Sarcoidosis and breast carcinoma: Three case reports and a review. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.867] [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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Cebon JS, Davis ID, Barrow C, Jackson H, Hopkins W, Miloradovic L, Parente P, Green S, Hoffman E, Chen W. Quantitation of immune responses against the cancer testis antigen NY-ESO-1 following vaccination with protein with and without ISCOMATRIX adjuvant. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.2518] [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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1398
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Chen W, Li S, Cook NR, Rosner BA, Srinivasan SR, Boerwinkle E, Berenson GS. An autosomal genome scan for loci influencing longitudinal burden of body mass index from childhood to young adulthood in white sibships: The Bogalusa Heart Study. Int J Obes (Lond) 2004; 28:462-9. [PMID: 14993914 DOI: 10.1038/sj.ijo.0802610] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To examine genetic loci linked to a long-term burden and trend of obesity traits, such as body mass index (BMI), from childhood to adulthood. DESIGN : Longitudinal study using serial measurements of BMI from childhood. SUBJECTS A total of 782 unselected white siblings (representing 521 full and 39 half sib-pairs) from 342 families enrolled in the Bogalusa Heart Study. MEASUREMENTS A total of 357 microsatellite markers with an average spacing of 9.0 cM spanning the 22 autosomal chromosomes were typed. A quadratic growth curve was developed using a random effects model based on serial measurements of BMI from childhood to adulthood. The serial changes in BMI were measured in terms of long-term burden (area under the curve (AUC) divided by follow-up years) and the long-term trend (incremental AUC, calculated as total AUC-baseline AUC). RESULTS Heritability estimates of long-term measures were 0.78 for total AUC and 0.43 for incremental AUC. In a variance-component-based multipoint linkage analysis with SOLAR, linkage to the long-term measures of BMI was observed on chromosomes 1, 5, 7, 12, 13 and 18. For total AUC, LOD scores were 3.0 at 110 cM on chromosome 12, 2.9 at 26 cM and 2.4 at 52 cM on chromosome 7, and 2.2 at 126 cM on chromosome 5. For incremental AUC, LOD scores were 2.9 at 26 cM, 2.1 at 97 cM and 2.3 at 110 cM on chromosome 12, 2.2 at 69 cM on chromosome 7, 2.2 at 91 cM and 2.5 at 150 cM on chromosome 1, 2.0 at 119 cM on chromosome 5, 2.0 at 54 cM on chromosome 13 and 2.0 at 7 cM on chromosome 18. Several important obesity-related candidate genes are located in the regions or near the markers showing positive linkage. CONCLUSION Linkage evidence found in this study indicates that regions on these chromosomes might harbor genetic loci that affect the propensity to develop obesity from childhood.
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Chen W, Ford MS, Young KJ, Zhang L. Infusion of in vitro-generated DN T regulatory cells induces permanent cardiac allograft survival in mice. Transplant Proc 2004; 35:2479-80. [PMID: 14611991 DOI: 10.1016/j.transproceed.2003.08.030] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Previously, we have demonstrated that pretransplant donor lymphocyte infusion (DLI) can activate recipient-derived CD3+CD4-CD8- double negative T regulatory (DN Tr) cells which have a potent immune regulatory function in vitro and in vivo. Here we studied the regulatory ability of DN T cell clones generated from the spleens of nai;ve anti-L(d) transgenic TCR+ (2C x dm2)F1 mice. We were able to identify subsets of DN T cell clones that were able to kill anti-Ld CD8+ T cells, and therefore had regulatory properties, and DN T cells with no regulatory properties. Next, we investigated the ability of these in vitro generated DN T cell clones to enhance cardiac allograft survival. (2C x dm2)F1 transgenic mice were infused with either regulatory or non-regulatory DN T cell clones, or left untreated one day before receiving an Ld-mismatched cardiac grafts from (C57BL/6 x Balb/c)F1 mice. Injection of non-regulatory DN T clone cells did not prolong cardiac graft survival in (2C x dm2)F1 mice when compare to untreated controls. In contrast, all of the cardiac grafts survived more than 100 days in mice that received DN Tr clone cells prior to transplantation. These results demonstrate that DN Tr cells can be generated in vitro and protect cardiac allograft from rejection when infused into recipients prior to transplantation. They also suggest that DN Tr cells may provide a novel therapy for the treatment of allograft rejection.
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Chen W, Steen FM, Green PG. Upgrading of existing sludge treatment processes for phosphorus management serving a EBPR WWTP. ENVIRONMENTAL TECHNOLOGY 2004; 25:523-531. [PMID: 15242228 DOI: 10.1080/09593330.2004.9619343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
For a large-scale wastewater treatment plant to comply with phosphorus consents using enhanced biological phosphorus removal processes, its sludge and liquor treatment processes need to be carefully upgraded. In this case study, the wastewater treatment plant of interest has three different types of sludge treated by two different and independent sludge treatment processes. The task of upgrading the sludge treatment systems to serve an EBPR process while satisfying other regulatory and operational constraints in a cost effective way presents an interesting challenge. A range of process options was investigated to include P-rich surplus activated sludge treatment, raw sludge treatment, and sludge liquors treatment. Sludge pre-liming, i.e. to introduce lime slurry into raw liquid sludge before the dewatering stage, was studied in bench-scale and full-scale trials for phosphorus precipitation and pathogen reduction. It was applied to the mixture of surplus activated sludge and imported sludge. The results showed that a complete phosphorus precipitation was achieved at above pH 9 with lime addition of 7% (w/w as calcium hydroxide to sludge dry weight). A satisfactory 2-log pathogen reduction was consistently achieved at above pH 11 with lime addition of 14% (w/w). The process significantly simplified the potential upgrading work for sludge and liquor treatment, compared to other alternatives.
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