Publications by authors named "Donna Horncastle"

Purpose: The expression of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) is associated with poor prognosis in sporadic colorectal carcinoma (CRC). EGFR inhibitors are approved for the treatment of refractory CRC. The aim of this study was to investigate the expression of EGFR and HER2 and downstream extracellular signal regulated kinase (ERK) and mitogen activated protein kinase (MAPK) in non-neoplastic colonic mucosa, adenomas and carcinomas from familial adenomatous polyposis coli (FAP) patients, exploring the expression along the adenoma-carcinoma sequence.

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Solid pseudopapillary tumor (SPT) of the pancreas is an uncommon neoplasm of uncertain lineage. They have been shown to express nuclear beta-catenin believed to be due to mutations of the beta-catenin gene. The aim of this study was to investigate the status of the E-cadherin/catenin complex in SPTs.

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Bcl-6 is expressed in germinal centre derived B-cell non-Hodgkin lymphomas including diffuse large B-cell lymphoma (DLBCL) and is likely to play a major role in driving proliferation of a subset of DLBCLs, especially those of germinal centre B-cell subtype, but the role of c-Myc, which is important for proliferation in various lineages is not known. We used the highly standardised staining conditions of a tissue microarray to characterise co-expression of c-Myc and Bcl-6 in DLBCL. We carried out immunohistochemistry of 73 arrayed cases.

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CXCL8 is a chemokine that is implicated in the formation of tuberculous (TB) granulomas and in immunity to Mycobacterium tuberculosis (Mtb). Fibroblast chemokine secretion is important for modulating inflammatory responses in chronic lung disease and inflammatory arthritis but has not been investigated in the pathophysiology of TB. In this study, we used a cellular model to examine monocyte/macrophage-dependent stimulation of fibroblasts by Mtb in the regulation of chemokine secretion, particularly that of CXCL8.

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An increase in leucocyte apoptosis and impaired clearance of apoptotic cells has been observed in patients with systemic lupus erythematosus (SLE). Apoptotic cells are likely to be a key source of autoantigens in SLE as they express many of the nuclear autoantigens (in surface blebs and apoptotic bodies) that are relevant to this disease. The clearance of apoptotic cells is usually a rapid process, such that few cells are usually seen in the extracellular environment in vivo.

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CNS tuberculosis (CNS-TB) is the most deadly form of tuberculous disease accounting for 10% of clinical cases. CNS-TB is characterized by extensive tissue destruction, in which matrix metalloproteinases (MMPs) may play a critical role. We investigated the hypothesis that Mycobacterium tuberculosis activates monocyte-astrocyte networks increasing the activity of key MMPs.

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Matrix metalloproteinase-9 (MMP-9) activity is implicated in pathogenesis of central nervous system tuberculosis (CNS-TB). IFNgamma, a key cytokine in TB, usually inhibits MMP-9 secretion. Addition of IFNgamma to conditioned media from M.

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The minichromosome maintenance (Mcm) and Cdc6 proteins are important regulators of eucaryotic DNA replication. In most normal tissues, a similar proportion of cells express Mcm-2 and Ki-67. The present study showed that in both normal and abnormal states, the proportion of megakaryocytes expressing Mcm-2 is roughly seven times as many as those that express Ki-67.

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Pulmonary cavitation is vital to the persistence and spread of Mycobacterium tuberculosis (MTb), but mechanisms underlying this lung destruction are poorly understood. Fibrillar type I collagen provides the lung's tensile strength, and only matrix metalloproteinases (MMPs) can degrade it at neutral pH. We investigated MTb-infected lung tissue and found that airway epithelial cells adjacent to tuberculosis (Tb) granulomas expressed a high level of MMP-1 (interstitial collagenase).

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Rationale: Pulmonary cavitation is fundamental to the global success of Mycobacterium tuberculosis. However, the mechanisms of this lung destruction are poorly understood. The biochemistry of lung matrix predicts matrix metalloproteinase (MMP) involvement in immunopathology.

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