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Various studies suggested that inflammation is involved in the pathogenesis of Alzheimer's disease (AD). We investigated cytokine release from LPS-stimulated blood cells of 32 AD patients, with different disease severity, compared to 16 age-related controls. A significant decrease of IL-1beta and IL-6 secretion was observed in severely demented patients; TNF-alpha release was also decreased, but not significantly. By contrast, mild and moderate patients showed a cytokine release similar to controls. IL-1beta, IL-6 and TNF-alpha secretion was negatively correlated with the severity of dementia, quantified by the MMSE. Our data suggest that alterations of the immune profile are associated with AD progression.  相似文献   
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Human monoclonal antibodies against amyloid-beta from healthy adults   总被引:4,自引:0,他引:4  
Two anti-amyloid-beta human antibody-producing cell lines were established from amyloid-beta (Abeta)-selected lymphocytes from peripheral blood of healthy adults. ELISA and Western blot analysis showed that the monoclonal antibodies bound with high affinity to the 43 amino acid-long amyloid-beta peptide. The antigen epitope of these antibodies encountered within amino acids 1-16 of the amyloid-beta peptide. The antibodies did not bind to several immunoglobulin light chain amyloids (AL) and amylin. One of the monoclonals was tested by immunohistochemistry for the binding to frozen sections of brains derived from patients with Alzheimer's disease. It specifically and intensively stained diffuse and core amyloid-beta plaques; whereas, sections from normal brains were not stained. Concomitant staining with a commercial mouse anti-amyloid-beta monoclonal antibody co-localized with that of the human antibody. Simultaneous staining with the human antibody and Congo red implied that the antibody binds primarily to an early immature form of beta-amyloid. Human monoclonal antibodies, which resemble physiologically normal non-pathogenic and possibly protective antibodies in healthy adults, might be attractive candidates for immune therapy of Alzheimer's disease.  相似文献   
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Background  

The CXCL1 chemokines, macrophage inflammatory protein-2 (MIP-2) and cytokine-induced neutrophil chemoattractant (KC), have been shown to play a role in a number of pathophysiological disease states including endotoxin-induced inflammation and bacterial meningitis. While the expression of these chemokines has been identified in a variety of cell types in the mouse, little is known about their expression with murine B-lymphocytes.  相似文献   
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Background: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people’s lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March–May lockdown. Methods: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. Results: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. Conclusions: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life.  相似文献   
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We measured severe acute respiratory syndrome coronavirus 2 spike protein subunits S1/S2 antibodies by using capillary electrophoresis and a chemiluminescence immunoassay for 5,444 active healthcare workers in Italy. Seroprevalence was 6.9% and higher among participants having contact with patients. Seroconversion was not observed in 37/213 previously infected participants.  相似文献   
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