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There is a lack of biochemical markers for non-invasive and objective assessment of symptomatic osteoarthritis (OA). Aggrecanase activity has been shown to be associated with joint deterioration and symptomatic disease through the degradation of extracellular matrix proteins, such as type III collagen. Our study aimed to identify and develop a novel biomarker by measuring an aggrecanase-mediated type III collagen neoepitope, and correlate levels of this biomarker with OA joint pain. Mass spectrometric analysis of purified type III collagen, degraded by the aggrecanase A Disintigrin and Metalloproteinase with Thrombospondin motif (ADAMTS), revealed a fragment generated by ADAMTS-1, -4 and -8. A monoclonal antibody was raised against the neoepitope of this fragment (COL3-ADAMTS) and a competitive ELISA was developed and tested; using serum samples from a cross-sectional cohort of patients with different degrees of knee OA (n = 261). The COL3/ADAMTS ELISA was technically robust and specific for the ADAMTS-1, -4 and -8 generated neoepitope. COL3/ADAMTS was released form cytokine stimulated synovial cultures, indicating a biologic link between the marker and synovium. In OA patients, serum COL3/ADAMTS was independently associated with pain scores (rho = −0.13–0.17, p < 0.05). This association was associated significantly with the presence of radiographic OA. Together, these data indicate that COL3/ADAMTS could be a marker of early osteoarthritis and the underlining pathology.  相似文献   
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《Alzheimer's & dementia》2008,4(5):332-344
BackgroundThis work sought to determine the effects of hypothalamic proline-rich peptide (PRP)-1 in a rat model of Alzheimer's disease.MethodsComplex histochemical, electrophysiologic, and behavioral analyses were performed on intact or diseased Wistar rats (n = 28). Pathologic conditions were induced by bilateral intracerebroventricular injection of amyloid peptide Aβ25–35. The diseased rats received systemic administration of PRP-1 or placebo control.ResultsAβ25–35 caused cellular neurodegeneration with marked glial reaction in the hippocampal complex and almost full destruction of the dentate fascia, which was not observed in conditions of PRP-1 administration after Aβ25–35 injection. Hippocampal neurons of intact animals responded to high-frequency (tetanic) stimulation of entorhinal cortex of ipsilateral cerebral hemisphere by tetanic and posttetanic potentiation of a different intensity and duration, which was accompanied by posttetanic depression. Aβ25–35 led to significant changes in the level and pattern of hippocampal neuronal activity, indicating the absence of both tetanic and posttetanic activity. Poststimulus activity manifestations rarely occurred and rapidly decreased after repeated trials. This indicated the focal character of lesion. Regular administration of PRP-1 for 4 weeks resulted in optimal restoration of electrophysiologic parameters. PRP-1 maintained the initial learning level achieved in a behavioral study in a Morris water maze.ConclusionsSystemic administration of PRP-1 possesses neuroprotective effects and can prevent the neurodegeneration in hippocampus induced by Aβ25–35. This suggests that PRP-1 could be a potential therapeutic agent for specific neurodegenerative diseases.  相似文献   
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Lipoprotein transport is thought to occur in the plasma compartment of the blood, where lipoproteins are modulated by various enzymatic reactions. Subsequently, lipoproteins can migrate through the endothelial barrier to the subendothelial space or are taken up by the liver. The interaction between pro-atherogenic (apoB-containing) lipoproteins and blood cells (especially monocytes and macrophages) in the subendothelial space is well known. This lipoprotein-inflammatory cell interplay is central in the development of the atherosclerotic plaque. In this review, a novel interaction is described between lipoproteins and both leukocytes and erythrocytes in the blood compartment. This lipoprotein-blood cell interaction may also be related to the process of atherosclerosis by inducing inflammatory changes in the case of leukocytes (pro-atherogenic) and as an anti-atherogenic transport-system by adherence to erythrocytes. Triglyceride rich lipoprotein (TRL)-mediated leukocyte activation can lead to an inflammatory situation with generation of oxidative stress and the production of cytokines, ultimately resulting in acute endothelial dysfunction. Binding of apoB containing lipoproteins to erythrocytes may be a potential anti-atherogenic mechanism protecting the vessel wall from the pro-inflammatory effects of these lipoproteins and also playing a role in the removal of these particles from the circulation. One of the proposed mechanisms of this interaction implies complement activation on the lipoprotein surface and binding to the Complement Receptor 1 (CR1) on erythrocytes and leukocytes, followed by clearance by the liver.  相似文献   
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The Pawtucket Heart Health Program employs a community activationapproach aimed at reducing cardiovascular morbidity and mortality.This approach is put into operation through the recruitmentof lay volunteers from the community to assist in planning,implementing, evaluating and managing various components ofthe Program. This unique approach of voluntary delivery of programmesis presented in this report. Strategies for the recruitment,interview and placement, training, maintenance and evaluationof volunteers are discussed. The characteristics of people whohave volunteered for specific administrative and service deliveryjobs with the Pawtucket Heart Health Program are also described.The volunteer delivery focus of the Program provides a modelfor adaptation by other public health projects.  相似文献   
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ObjectivesCancer Testis Antigens are immunogenic tumor-specific proteins. We investigated NY-ESO-1, MAGE-A3 and PRAME, in addition to WT1 expression in different Breast Cancer (BC) subtypes. We then evaluated the expression rate of NY-ESO-1 in early Triple Negative breast cancer (TNBC), and investigated whether its expression would be maintained or lost in the metastatic setting to explore possible immunotherapy indication.Materials and methodsThree subgroups of BC patients were selected by the expression of ER, PgR and Her2. Tissue microarray was performed on a total of 92 Invasive BC. Sections were stained for NY-ESO-1, MAGE-A3, PRAME and WT1. The second cohort was composed by 26 metastatic TNBC patients from whom both the primary and secondary lesion tissues were available. Sections were stained for NY-ESO-1.ResultsNY-ESO-1 was the only differentially expressed antigen and was absent in ER+ and ER-PgR + tumors, as for an exclusive expression of either NY-ESO-1 or at least one hormonal receptor (HR+). NY-ESO-1 was particularly represented in TNBC. No correlation has been found between MAGE-A3 and PRAME expression and subtype WT1 had low expression, except in the Her2+ group. In the second cohort, NY-ESO-1 was expressed in 12 and 24% of primary and metastatic lesions respectively.ConclusionsThis study defines a distinction between HR+ and HR-tumors through NY-ESO-1 expression.TNBC subgroup has the highest frequency of NY-ESO-1+ cases, and it could be the candidate population for the development of anti-NY-ESO-1 vaccine, both in the adjuvant or metastatic setting, and for the selection of cases suitable for immunotherapy.  相似文献   
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