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Introduction: The rising prevalence of musculoskeletal pathologies in developed countries has caused a dramatic impact on social welfare. Amidst these musculoskeletal pathologies is Rheumatoid arthritis (RA), a chronic systemic autoimmune disease that mostly affects the synovium. RA metabolic-associated alterations, including distorted adipokine production, enhance RA inflammatory environment. Among the altered adipokines, visfatin is particularly involved in RA inflammation and catabolism and stands out as an essential enzyme linked to critical cell features.

Areas covered: We discuss the potential mechanism supporting the contribution of visfatin to RA and the association between RA and obesity. We discuss the repurposing of cancer-tested drugs to inhibit visfatin in the context of RA. Additionally, we address the possibility of combining these drugs with current RA therapy. Finally, we explore the future of visfatin as an RA biomarker or therapeutic target.

Expert opinion: Inhibition of visfatin has become an interesting therapeutic approach for RA pathology. Such a feat has already been attained in oncology using small molecule inhibitors, which suggest that a similar course of action would be worth pursuing in the RA context. Visfatin will become an important biomarker and therapeutic target for RA.  相似文献   

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We have previously reported that human T cell receptors (TcR) selected in the class II-restricted (HLA-DRB1*1302) response to a tetanus toxin peptide (tt830-843) frequently used the Vβ2 germ-line segment which paired with several Vα segments and that the putative CDR3 of both α and β chains showed remarkable heterogeneity. To analyze the structural basis for recognition of the tt830-843/DR complex, five of these TcR were reconstituted into a murine T cell hybridoma, 58 α?β?, by expressing the human α and β variable regions joined to the mouse α and β constant regions, respectively. The chimeric TcR, expressing the same Vβ germ-line segment (Vβ2), two expressing Vα21.1, twoVα17.1 and one Vα8.1 were shown to have the expected antigen specificity and DR restriction. Two lines of evidence suggested that the putative CDR3, although not conserved in these TcR, played a key role in recognition. First, two TcR with identical V germ-line segments but distinct CDR3 showed large differences in their capacity to react with the ligand. Second, interchanging the α and β chains from tt830-843/DR1302-specific TcR which differed in their CDR3 sequences invariably led to loss of recognition. We also asked whether germ-line Vα17.1 could functionally replace Vα21.1, as they appear to be related in their primary sequence. However, as in the case of CDR3 exchanges, Vα replacement abrogated TcR reactivity. Taken together, these data underline the fine interdependence of the structural components of the TcR binding site in defining a given specificity. Four of the TcR studied displaying promiscuous recognition were also tested against different DR alleles and site-directed mutants. The results of these experiments suggested that, in spite of their structural heterogeneity, anti-tt830-843 TcR may have a similar orientation with respect to the peptide/DR complex. The reconstitution system described herein should represent a valuable tool for detailed studies of human TcR specificity.  相似文献   
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Par o I, a major allergen of Parietaria officinalis, was purified from the pollen extract. The purified allergen was obtained by ultrafiltration, Sephadex gel filtration and DE-52 ion exchange chromatography: the purified preparation yields a single band in polyacrylamide gel isoelectric focusing (PAG-IEF), sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting, a single immunoprecipitation arc in crossed immunoelectrophoresis (CIE) and crossed radioimmunoelectrophoresis (CRIE) and a single peak in size exclusion high-performance liquid chromatography (HPLC). Par o I is a glycoprotein with a protein to carbohydrate ratio of 100:21. The molecular weight, determined by SDS-PAGE, Sephadex G-50 gel filtration and size exclusion HPLC, varied between 13.5 and 14.5 kDa according to the method employed. The isoelectric point was 4.6. The amino acid composition and the sequence of the first twelve N-terminal residues were determined. The allergenicity was assayed in vivo and in vitro. 29/29 Parietaria-allergic patients were skin positive to Par o I and possessed high level of specific serum IgE antibody as it determined by radioallergosorbent test (RAST). Par o I contained dominant epitopes for human IgE as inhibited to 85% the pollen extract RAST performed with a pool of sera of allergic patients. The RAST inhibitory activity was not abolished by deglycosylation.  相似文献   
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The goal of this study was to analyze the correlation between inducible nitric oxide synthase (iNOS) and COX-2 activities and p53 gene status in head and neck squamous cell carcinomas (HNSCCs) in vivo and in vitro. In a series of 43 HNSCCs we observed an up-regulation of both iNOS and COX-2 pathways in tumor tissues and both activities were correlated each other (rs = 0.612 and P = 0.0002). We also found that p53-mutated HNSCCs (25 cases, 58.1%) showed higher levels of iNOS activity and cGMP in comparison with wild-type p53 tumors (18 cases, 41.9%) (P = 0.0005 and P = 0.01), as well as higher iNOS immunohistochemical expression (P = 0.03). Analogously, higher PgE2 levels were documented in p53-mutated HNSCCs when compared with wild-type p53 tumors (P = 0.015) and COX-2 protein expression was higher in p53-mutated HNSCCs (P = 0.007). A431 cancer cells expressing a p53 temperature-sensitive mutant showed an approximately 1.9- and 2.6-fold decrease in spontaneous NO(2-)/NO(3-) and PgE2 synthesis at permissive temperature, respectively, when compared with the same cells at nonpermissive temperature (P 相似文献   
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To investigate the intra-hepatic activation of the IFN system in patients affected by chronic HCV-infection in comparison with that observed in a non-infectious liver disease such as non-alcoholic steatohepatitis, we measured the liver steady state mRNA levels of interferon-alpha, interferon-beta and interferon-gamma as well as of IFN-related genes (IFNAR-1, STAT1alpha, PKR, 2-5 AS, IRF-1, ICE and IL-18). In HCV-infected subjects, possible correlations of these parameters with viral load and liver injury were also analyzed. Twenty-four chronic untreated HCV-infected subjects and seven patients with non-alcoholic steatohepatitis were enrolled in the study. Liver biopsies were graded according to Knodell scores. Intra-hepatic mRNA levels of IFNs and related genes were assessed by semi-quantitative RT-PCR. In comparison with non-alcoholic steatohepatitis, in HCV-infected subjects IFN-alpha and -beta mRNA levels were significantly lower, whereas IFN-gamma, IFNAR-1, STAT1alpha IRF-1, and IL-18 mRNA were upregulated. Moreover, IFN-gamma mRNA steady state levels were correlated positively with those of IFNAR-1, IRF-1, and IL-18, suggesting a coordinated induction of these genes. Although plasma viral load was correlated inversely with IL-18-specific mRNA, viral load was not related to liver injury. IFN-gamma and IRF-1 mRNA levels were correlated positively with ALT, but not with the grading or staging. Conversely, IFN-alpha and -beta mRNA levels were higher in livers with lower staging scores. These findings support the hypothesis that in chronic HCV infection there is an imbalance between an upregulated IFN-gamma system and a downregulated IFN-alpha and -beta system, probably due to a mixed effect exerted by HCV-specific and inflammatory non-specific factors.  相似文献   
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Prostaglandins play a critical role in tumor development and growth by regulating numerous biologic processes, including tumor angiogenesis, with clear prognostic and therapeutic implications. The aim of this study was to investigate the prognostic relevance of cyclooxygenase-2 (COX-2) pathway activation in head and neck squamous cell carcinoma (HNSCC). COX-2 activity was analyzed in 52 consecutive patients by assessing protein expression and prostaglandin E(2) (PgE(2)) levels and was then correlated to vascular endothelial growth factor (VEGF) expression and tumor angiogenesis. We evaluated the prognostic impact of these parameters by Kaplan-Meier and Cox survival analysis. COX-2 expression by tumor cells was closely correlated to VEGF expression and to tumor vascularization. According to Kaplan-Meier analysis, patients with COX-2 tumor overexpression and with higher PgE(2) tumor levels had significantly shorter overall survival estimates (P = 0.022 and P = 0.033, respectively). Analogously, patients with more-vascularized tumors had worse survival than those with less-vascularized cancers (P = 0.032). Cox multivariate analysis demonstrated that the most significant prognostic factors were presence of lymph node metastasis, tumor vascularization, COX-2 protein expression, and PgE(2) tumor levels. This study demonstrates a close correlation between COX-2 pathway, VEGF expression, and tumor angiogenesis in HNSCC. In addition, COX-2 overexpression and higher tumor vascularization appear to predict a shorter survival in patients with head and neck cancer.  相似文献   
9.
Journal of Clinical Immunology - A Correction to this paper has been published: https://doi.org/10.1007/s10875-021-01030-6  相似文献   
10.
BACKGROUND: Different methods of normalizing left ventricular (LV) mass for body size identify generally similar relative risks of adverse cardiovascular outcome but with variable prevalences of LV hypertrophy (H). Preliminary results from a population with high prevalence of obesity suggest that the population attributable-risk percent (PAR%) of LVH is substantially higher when LV mass is normalized for allometric power of height. METHODS: We calculated the PAR% of LVH by different definitions in the cohort of the MAssa Ventricolare sinistra nell' Ipertensione (MAVI) study (n = 1019, 62% women), a population with low prevalence of obesity (22%, with only 3% and 0.1% in class II and class III obesity, respectively). Composite fatal and nonfatal cardiovascular events occurred in 53 participants (5.2%). RESULTS: Prevalence of LVH was between 28% and 56%, with slight greater values for height-based normalization. Age- and sex-adjusted hazard ratios were comprised between 1.37 and 1.44 for different measures of LV mass index. The PAR% was not meaningfully different among the different methods of normalization (between 47% and 56%), and height-based methods showed in general a performance similar to body surface area-based normalizations. CONCLUSIONS: In a large clinical population of hypertensive subjects with low prevalence of obesity, population risk attributable to LV hypertrophy was not meaningfully different in relation to the type of normalization of LV mass for body size. Height-based methods perform as well as body surface area-based ones. We suggest that the prevalence of obesity in hypertensive populations might substantially influence differences in population risk attributable to LVH identified by different methods of normalizing LV mass.  相似文献   
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