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In many autoimmune rheumatic diseases, there is an increased risk of cancer compared to the general population. The link between autoimmunity and cancer is dynamic and bidirectional. Recent advances in terms of knowledge of biology, epidemiology, and long-term outcomes for the autoimmune rheumatic diseases have revealed several new connections between these two entities. Data suggest that chronic inflammation from the rheumatic diseases or their therapies may contribute to the onset and promotion of cancer. Conversely, antitumor immune responses may become cross-reactive with self-tissues resulting in the development of autoimmunity. In this review, we discuss about the potential mechanisms that link autoimmune rheumatic diseases and cancer and the association of malignancies with common autoimmune disorders. The increased incidence of malignancy in autoimmune rheumatic diseases has been largely described, although the biology underpinning this relationship should be further investigated. The development of evidence-based cancer screening recommendations in patients with autoimmune rheumatic diseases is complex due to the heterogeneity of clinical rheumatic phenotypes, cancer sites at risk and exposure to anti-neoplastic and anti-rheumatic treatment. In order to lay the foundation of risk stratification and targeted cancer screening, larger longitudinal cohort studies that provide a more detailed framework of the links between cancer and autoimmunity are urgently needed.  相似文献   
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The performance of biodegradable knitted and rolled 3‐dimensional (3D) polylactide‐based 96/4 scaffolds modified with bioactive glass (BaG) 13‐93, chitosan and both was compared with regard to the viability, proliferation and chondrogenic differentiation of rabbit adipose stem cells (ASCs). Scaffold porosities were determined by micro‐computed tomography (μCT). Water absorption and degradation of scaffolds were studied during 28‐day hydrolysis in Tris‐buffer. Viability, number and differentiation of ASCs in PLA96/4 scaffolds were examined in vitro. The dimensions of the scaffolds were maintained during hydrolysis and mass loss was detected only in the BaG13‐93 containing scaffolds. ASCs adhered and proliferated on each scaffold type. Cell aggregation and expression of chondral matrix components improved in all scaffold types in chondrogenic medium. Signs of hypertrophy were detected in the modified scaffolds but not in the plain PLA96/4 scaffold. Chondrogenic differentiation was most enhanced in the presence of chitosan. These findings indicate that the plain P scaffold provided a good 3D‐matrix for ASC proliferation whereas the addition of chitosan to the PLA96/4 scaffold induced chondrogenic differentiation independent of the medium. Accordingly, a PLA96/4 scaffold modified by chitosan could provide a functional and bioactive basis for tissue‐engineered chondral implants. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Background

Poor response to loop diuretic therapy is a marker of risk during heart failure hospitalization. We sought to describe baseline determinants of diuretic response and to further explore the relationship between this response and clinical outcomes.

Methods and Results

Patient data from the National Heart, Lung, and Blood Institute Heart Failure Network ROSE-AHF and CARRESS-HF clinical trials were analyzed to determine baseline determinants of diuretic response. Diuretic efficiency (DE) was defined as total 72-hour fluid output per total equivalent loop diuretic dose. Data from DOSE-AHF was then used to determine if these predictors of DE correlated with response to a high- versus low-dose diuretic strategy. At 72 hours, the high-DE group had median fluid output of 9071 ml (interquartile range: 7240–11775) with median furosemide dose of 320 mg (220–480) compared with 8030 ml (6300–9915) and 840 mg (600–1215) respectively for the low DE group. Cystatin C was independently associated with DE (odds ratio 0.36 per 1mg/L increase; 95% confidence interval: 0.24–0.56; P < 0.001). Independently from baseline characteristics, reduced fluid output, weight loss and DE were each associated with increased 60 day mortality. Among patients with estimated glomerular filtration rate below the median, those randomized to a high-dose strategy had improved symptoms compared with those randomized to a low-dose strategy.

Conclusions

Elevated baseline cystatin C, as a biomarker of renal dysfunction, is associated with reduced diuretic response during heart failure hospitalization. Higher loop diuretic doses are required for therapeutic decongestion in patients with renal insufficiency. Poor response identifies a high-risk population.  相似文献   
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Severe GN involves local neutrophil extracellular trap (NET) formation. We hypothesized a local cytotoxic effect of NET-related histone release in necrotizing GN. In vitro, histones from calf thymus or histones released by neutrophils undergoing NETosis killed glomerular endothelial cells, podocytes, and parietal epithelial cells in a dose-dependent manner. Histone-neutralizing agents such as antihistone IgG, activated protein C, or heparin prevented this effect. Histone toxicity on glomeruli ex vivo was Toll-like receptor 2/4 dependent, and lack of TLR2/4 attenuated histone-induced renal thrombotic microangiopathy and glomerular necrosis in mice. Anti–glomerular basement membrane GN involved NET formation and vascular necrosis, whereas blocking NET formation by peptidylarginine inhibition or preemptive anti-histone IgG injection significantly reduced all aspects of GN (i.e., vascular necrosis, podocyte loss, albuminuria, cytokine induction, recruitment or activation of glomerular leukocytes, and glomerular crescent formation). To evaluate histones as a therapeutic target, mice with established GN were treated with three different histone-neutralizing agents. Anti-histone IgG, recombinant activated protein C, and heparin were equally effective in abrogating severe GN, whereas combination therapy had no additive effects. Together, these results indicate that NET-related histone release during GN elicits cytotoxic and immunostimulatory effects. Furthermore, neutralizing extracellular histones is still therapeutic when initiated in established GN.  相似文献   
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