544 results match your criteria: "John P. Robarts Research Institute[Affiliation]"
Lymphat Res Biol
April 2020
Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada.
Surgical excision and/or radiation targeting of regional lymph nodes are an essential component in the clinical management of cancer. Importantly, a more accurate understanding of lymphatic anatomy could enable refinement of present treatment strategies. Given the spatial resolution limitations of contemporary imaging methods, our group sought to utilize noncontrast-enhanced microcomputed tomography (μCT) imaging to clarify regional lymphatic anatomy.
View Article and Find Full Text PDFJ Orthop Res
March 2019
Physiology and Pharmacology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, Canada.
Diffuse idiopathic skeletal hyperostosis (DISH) is a non-inflammatory spondyloarthropathy identified radiographically by calcification of the ligaments and/or entheses along the anterolateral aspect of the vertebral column. The etiology and pathogenesis of calcifications are unknown, and the diagnosis of DISH is currently based on radiographic criteria associated with advanced disease. To characterize the features of calcifications associated with DISH, we used micro-computed tomographic imaging to evaluate a cohort of 19 human cadaveric vertebral columns.
View Article and Find Full Text PDFEndocr Metab Immune Disord Drug Targets
December 2006
John P. Robarts' Research Institute, London, ON, Canada.
Inflammatory and immune responses are inherent in the development of progressive arthritic or vasculitic disorders. Arthritis is frequently associated with accelerated forms of vasculitis; atherosclerosis being one form of accelerated vasculitis that blocks blood flow causing heart attacks and strokes. The arterial supply is central to maintaining normal articular function and acts as a conduit for inflammatory (innate) and immune (antigen dependent) cell trafficking in joints.
View Article and Find Full Text PDFDev Biol
February 2007
BioTherapeutics Research Group, The John P Robarts Research Institute, and The University of Western Ontario, London, Ontario, Canada.
Eph proteins are receptor tyrosine kinases that control changes in cell shape and migration during development. We now describe a critical role for EphA3 receptor signaling in heart development as revealed by the phenotype of EphA3 null mice. During heart development mesenchymal outgrowths, the atrioventricular endocardial cushions, form in the atrioventricular canal.
View Article and Find Full Text PDFMethods Mol Biol
August 2006
The John P. Robarts Research Institute, Stem Cell Biology and Regenerative Medicine, London, Ontario, Canada.
It has been recently identified that cytokines and BMP-4 promote hematopoiesis from human embryonic stem cells (hESC) and that, before hematopoietic commitment, a rare subpopulation of cells lacking CD45, but expressing PECAM-1, Flk-1, and VE-cadherin (hereinafter termed CD45(neg)PFV precursors), are exclusively responsible for hematopoietic cell fate on cytokine stimulation. Efficient strategies to stably transduce these hematopoietic precursors specifically generated from hESCs would provide a novel and desirable tool to study hematopoietic development through the introduction and characterization of candidate genes suspected to regulate self-renewal processes of hESC-derived hematopoietic cells or dynamically track hESC-derived hematopoietic stem cells in vivo. To date, only transient transfection and stable transduction using lentiviral vectors have been reported in undifferentiated hESC followed by random and spontaneous differentiation into different cell types.
View Article and Find Full Text PDFMethods Mol Biol
August 2006
The John P. Robarts Research Institute, Stem Cell Biology and Regenerative Medicine, London, Ontario, Canada.
In vitro, the aggregation of pluripotent human embryonic stem cells (hESC) into cell clusters termed embryoid bodies (EB) allows for the spontaneous differentiation of hESC into progeny representing endoderm, mesoderm, and ectoderm lineages. During human EB (hEB) differentiation, stochastic emergence of hematopoietic cells can be enhanced by a combination of hematopoietic cytokines and the ventral mesoderm inducer bone morphogenetic protein (BMP)-4. Dependent on the presence of hematopoietic cytokines and BMP-4, vascular endothelial growth factor (VEGF-A165) selectively promotes erythropoietic development toward the primitive lineage.
View Article and Find Full Text PDFMethods Mol Biol
August 2006
The John P. Robarts Research Institute, Stem Cell Biology and Regenerative Medicine, London, Ontario, Canada.
Dopaminergic neurons of human origin have many potential research applications such as in vitro studies on biochemical pathways related to neuronal disorders, and potentially direct cell replacement for therapeutic use. Dopaminergic neurons with apparently normal properties can be produced from embryonic stem cells from mice and sub-human primates by the simple procedure of coculturing with the PA6 stromal cell line. Recently, we have demonstrated that this coculture system can induce dopaminergic differentiation in human embryonic stem cells, and the human embryonic stem cell-derived dopaminergic cells exhibit biochemical and functional properties of mature dopaminergic neurons.
View Article and Find Full Text PDFBiochim Biophys Acta
April 2006
Laboratory of Neural Signaling, Cell Biology Group, The John P. Robarts Research Institute, London, Ontario, Canada N6A 5K8.
We have investigated the signaling properties of the fibroblast growth factor (FGF) receptor substrate 3 (FRS3), also known as SNT-2 or FRS2beta, in neurotrophin-dependent differentiation in comparison with the related adapter FRS2 (SNT1 or FRS2alpha). We demonstrate that FRS3 binds all neurotrophin Trk receptor tyrosine kinases and becomes tyrosine phosphorylated in response to NGF, BDNF, NT-3 and FGF stimulation in transfected cells and/or primary cortical neurons. Second, the signaling molecules Grb2 and Shp2 bind FRS3 at consensus sites that are highly conserved among FRS family members and that Shp2, in turn, becomes tyrosine phosphorylated.
View Article and Find Full Text PDFIDrugs
September 2000
The John P Robarts Research Institute, Gene Therapy & Molecular Virology Group, PO Box 5015, 100 Perth Drive, London, Ontario N6A 5K8, Canada.
J Immunol
May 2005
Department of Microbiology and Immunology, University of Western Ontario, John P. Robarts Research Institute, London, Ontario, Canada.
Islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP) has been identified as a novel CD8(+) T cell-specific autoantigen in NOD mice. This study was undertaken to identify MHC class II-specific CD4(+) T cell epitopes of IGRP. Peptides named P1, P2, P3, P4, P5, P6, and P7 were synthesized by aligning the IGRP protein amino acid sequence with peptide-binding motifs of the NOD MHC class II (I-A(g7)) molecule.
View Article and Find Full Text PDFAliment Pharmacol Ther
February 2005
The John P Robarts Research Institute, University of Western Ontario, London, ON, Canada.
Aim: To evaluate CDP571, a humanized monoclonal antibody to tumour necrosis factor-alpha, for the treatment of corticosteroid-dependent Crohn's disease.
Methods: Patients with corticosteroid-dependent Crohn's disease (use of prednisolone 15-40 mg/day or budesonide 9 mg/day for at least 8 weeks, a previous failed attempt to discontinue corticosteroids within 8 weeks, and Crohn's Disease Activity Index score 150 points or less) were enrolled in a 16-week, randomized, double-blind, placebo-controlled trial. The patients received intravenous CDP571 (20 mg/kg at week 0 and 10 mg/kg at week 8) or placebo.
Hypersensitivity adverse drug reactions are much more common among patients with acquired immunodeficiency syndrome (AIDS) than in the general population. High rates of hypersensitivity reactions to clindamycin have been noted. To investigate the role of reactive metabolites in these reactions, the authors studied toxicity of clindamycin and sulphamethoxazole (SMX) and their metabolites in uninfected and human immunodeficiency virus (HIV)-infected MOLT3 cells.
View Article and Find Full Text PDFPhotochem Photobiol
September 2005
John P. Robarts Research Institute, London, ON, Canada.
Altered collagen and elastin content correlates closely with remodeling of the arterial wall after injury. Optical analytical approaches have been shown to detect qualitative changes in plaque composition, but the capacity for detection of quantitative changes in arterial collagen and elastin content in vivo is not known. We have assessed fluorescence spectroscopy for detection of quantitative changes in arterial composition in situ, in rabbit models of angioplasty and stent implant.
View Article and Find Full Text PDFCell Res
August 2004
Stem Cell Biology and Regenerative Medicine, The John P. Robarts Research Institute, 100 Perth Drive, London, Ontario, N6A 5K8, Canada.
With the exception of mature erythrocytes, cells within the human hematopoietic system are characterized by the cell surface expression of the pan-leukocyte receptor CD45. Here, we identify a novel subset among mononuclear cord blood cells depleted of lineage commitment markers (Lin-) that are devoid of CD45 expression. Surprisingly, functional examination of Lin-CD45- cells also lacking cell surface CD34 revealed they were capable of multipotential hematopoietic progenitor capacity.
View Article and Find Full Text PDFBackground: Both CC and CXC chemokines direct monocyte and T-cell migration and activation at sites of vascular injury, but the relative contributions of each chemokine class to transplant vasculopathy development have not been defined. The nonselective C, CC, and CXC chemokine binding protein, M-T7, inhibits vasculopathy development after angioplasty and after renal transplant. We have assessed the effects of three viral chemokine-binding proteins with differing ranges of chemokine inhibition on plaque growth in rats after aortic allograft transplant.
View Article and Find Full Text PDFAnn N Y Acad Sci
November 2003
John P. Robarts Research Institute, London, Ontario N6A 5C1, Canada.
The characterization of dendritic cells (DCs) in diabetes has primarily examined in vitro-generated DCs. In this study, we have compared the composition and phenotype of naturally occurring DCs within the peripheral blood of subjects with type 1 diabetes, latent-onset autoimmune diabetes in adults, and nondiabetic controls. We find that circulatory DC subsets exist in normal frequencies and phenotypic states in diabetic patients.
View Article and Find Full Text PDFJ Neurosci Res
December 2003
BioTherapeutics Research Group, The John P. Robarts Research Institute, London, Ontario, Canada.
The N-methyl-D-aspartate receptor (NMDAR) is a major neurotransmitter receptor in the central nervous system (CNS), with functional roles in learning, memory, and sensation. Several mechanisms potentiate NMDARs, and NMDAR hyperexcitability plays pathophysiological roles in many conditions, such as neurodegenerative disease, ischemia, and chronic conditions arising from spinal cord injury. Previous research suggests that the NR2A subunit of the receptor contributes to NMDAR excitotoxicity in heterologous cells and in neurons in vivo.
View Article and Find Full Text PDFJ Autoimmun
November 2003
Department of Microbiology and Immunology, University of Western Ontario, and John P. Robarts Research Institute, University of Western Ontario, London, N6A 5C1, Ontario, Canada.
NOD mice have a relative deficiency of CD4+CD25+ regulatory T cells that could result in an inability to maintain peripheral tolerance. The aim of this study was to induce the generation of CD4+CD25+ regulatory T cells in response to autoantigens to prevent type 1 diabetes (T1D). We found that immunization of NOD mice with insulin B-chain peptide B:9-23 followed by 72 h in vitro culture with B:9-23 peptide induces generation of CD4+CD25+ regulatory T cells.
View Article and Find Full Text PDFIEEE Trans Med Imaging
October 2003
Imaging Research Laboratories, The John P. Robarts Research Institute, London, ON N6A 5K8, Canada.
This paper addresses reprojection of three-dimensional (3-D) reconstructions obtained from cone-beam scans using a C-arm imaging equipment assisted by a pose-determining system. The emphasis is on reprojecting without decomposing the estimated projection matrix (P-matrix) associated with a pose. Both voxel- and ray-driven methods are considered.
View Article and Find Full Text PDFAnal Bioanal Chem
November 2003
The John P. Robarts Research Institute, 100 Perth Drive, N6G 4N9, London, ON, Canada,
Although ultrasonography is an important cost-effective imaging modality, technical improvements are needed before its full potential is realized for accurate and reproducible monitoring of disease progression or regression. Two-dimensional viewing of three-dimensional anatomy, using conventional ultrasonography, limits our ability to quantify and visualize pathology and is partly responsible for the reported variability in diagnosis and monitoring of disease progression. Efforts of investigators have focused on overcoming these deficiencies by developing 3D ultrasound imaging techniques that are capable of acquiring B-mode images using existing conventional ultrasound systems, reconstructing the information into 3D images, and then allowing interactive viewing of the 3D images on inexpensive desktop computers.
View Article and Find Full Text PDFMed Phys
July 2003
Imaging Research Laboratories, The John P. Robarts Research Institute, London, Ontario N6H 5C1, Canada.
Segmenting, or outlining the prostate boundary is an important task in the management of patients with prostate cancer. In this paper, an algorithm is described for semiautomatic segmentation of the prostate from 3D ultrasound images. The algorithm uses model-based initialization and mesh refinement using an efficient deformable model.
View Article and Find Full Text PDFCell Mol Biol (Noisy-le-grand)
March 2003
Department of Microbiology and Immunology, University of Western Ontario, John P. Robarts Research Institute, London, Ontario, Canada.
The present study was undertaken to analyze the regulatory T cells generated in response to class I derived self-I-A beta(g7) (54-76) peptide. It was observed T cells from young unprimed type 1 diabetes (T1D) prone NOD mice did not respond to self-I-A beta(g7) (54-76) peptide although T cells from primed young NOD mice showed a strong response. T cells from young unprimed BALB/c mice responded to self-I-A beta(d) (62-78) peptide.
View Article and Find Full Text PDFDiabetes
August 2003
Autoimmunity/Diabetes Group, the John P. Robarts Research Institute, London, Ontario, Canada.
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is expressed in different tissues and cells, including pancreas and lymphocytes, and can induce apoptosis in various tumor cells but not in most normal cells. The specific roles of TRAIL in health and disease remain unclear. Here we show by cDNA array analyses that TRAIL gene expression is upregulated in pancreatic islets during the development of autoimmune type 1 diabetes in nonobese diabetic (NOD) mice and in Min6 islet beta-cells activated by TNF-alpha + interferon-gamma.
View Article and Find Full Text PDFAm J Transplant
August 2003
The John P. Robarts Research Institute, Department of Microbiology, The University of Western Ontario, London, Ontario, Canada N6A 5K8.
Understanding the regulatory events involved in the activation and inactivation of T cells is crucial to develop therapeutic approaches for autoimmune diseases and for organ transplantation. Co-stimulatory signals delivered through the CD28 receptor and inhibitory signals through CTLA-4 are required for the proper modulation of T cell responses and the induction and maintenance of peripheral tolerance. Manipulation of these signals is emerging as a potential strategy to prevent allograft rejection in different animal models.
View Article and Find Full Text PDFCurr Drug Targets Cardiovasc Haematol Disord
December 2001
Vascular Biology Group, John P. Robarts Research Institute, London, Ontario, Canada.
Human apolipoprotein E (apoE) consists of a single polypeptide chain with 299 amino acids and is best known for its role in the transport of cholesterol and other lipids between peripheral tissues and the liver. However, more direct effects of apoE on the vascular wall may well contribute to arterial protection from atherosclerosis. This review will focus on: (a) the ability of apoE to direct cholesterol efflux mechanisms with the aid of apoA1 and the ATP binding cassette transporter 1 (ABC1); (b) the ability of apoE to prevent platelet aggregation by facilitating the production of endogenous nitric oxide (NO); (c) the ability of apoE to inhibit the proliferation of T-lymphocytes by internalization of the IL-2 receptor; and (d) the ability of apoE to inhibit proliferation of endothelial cells by out competing growth factors for interaction with cell surface heparan sulfate proteoglycans (HSPG's).
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