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目的 肝纤维化是一种由于反复肝损伤而导致肝组织细胞外基质过多沉积导致的疾病。缺氧损伤为肝损伤的一部分,缺氧诱导因子-1α(HIF-1α)是响应缺氧应激的关键转录因子,在肝纤维化组织和活化的肝星状细胞(HSC)表达显著增加。目前,通过对大量HIF-1α依赖性基因和信号通路的研究,确认这些基因及其通路的变化参与肝纤维化发展过程,并可能在肝纤维化发生发展过程中起关键作用。本文综述了HIF-1α相关的信号通路参与肝纤维化发展的相关机制,并对上游影响HIF-1α合成和降解的相关信号通路进行了阐述,为其作为新型治疗靶点的可能潜力提供依据。  相似文献   
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The extent of peritoneal metastases (PM) largely determines the possibility of complete or optimal cytoreductive surgery in advanced ovarian cancer. An objective scoring system to quantify the extent of PM can help clinicians to decide whether or not to embark on CRS. Therefore several scoring systems have been developed by different research teams and this review summarizes their performance in predicting a complete or optimal cytoreduction in patients with advanced ovarian cancer. A systematic search in the MEDLINE database revealed 19 articles that described a total of five main scoring systems to predict the completeness of CRS in patients with FIGO stage III-IV ovarian cancer based on the surgical exploration of the abdominal cavity; PCI, PIV, Eisenkop, Espada, and Kasper. The Peritoneal Cancer Index (PCI) and the Predictive Index Value (PIV) were mentioned most frequently and showed AUCs of 0.69–0.92 and 0.66–0.98, respectively. Due to the use of different cut-offs sensitivities and specificities greatly varied. Therefore with the current data, no scoring system could be identified as best. An objective measure of the extent of disease can be of great clinical use for identifying ovarian cancer patients for which a complete (or optimal) CRS is achievable, however due to local differences in treatment strategies and surgical policy a widely adopted objective scoring system with a standard cut-off value is not feasible. Nevertheless, objective scoring systems can play an important role to guide treatment decisions.  相似文献   
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Most of the patients who overcome the SARS-CoV-2 infection do not present complications and do not require a specific follow-up, but a significant proportion (especially those with moderate / severe clinical forms of the disease) require clinicalradiological follow-up. Although there are hardly any references or clinical guidelines regarding the long-term follow-up of post-COVID-19 patients, radiological exams are being performed and monographic surveillance consultations are being set up in most of the hospitals to meet their needs. The purpose of this work is to share our experience in the management of the post-COVID-19 patient in two institutions thathave had a high incidence of COVID-19 and to propose general follow-uprecommendations from a clinical and radiological perspective.  相似文献   
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Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
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PurposeCombined pulmonary fibrosis and emphysema (CPFE) has emerged as a new syndrome with characteristics of both fibrosis and emphysema. We determined the impacts of radiologic emphysema severity on pulmonary function tests (PFTs), exercise capacity and mortality.Patients and methodsIPF patients (n = 110) diagnosed at the Chest Diseases Clinic between September 2013 and January 2016 were enrolled in the study and followed up until June 2017. Visual and digital emphysema scores, PFTs, pulmonary artery pressure (sPAP), 6-minute walking test, composite physiologic index (CPI), and survival status were recorded. Patients with emphysema and those with pure IPF were compared.ResultsThe CPFE-group had a significantly greater ratio of men(p < 0.001), lower BMI (p < 0.001), lower mean PaO2 (p = 0.005), higher mean sPAP (p = 0.014), and higher exercise desaturation (p < 0.001). The CPFE group had a significantly higher FVC(L)(p = 0.016), and lower FEV1/FVC ratio (p = 0.002), DLCO, and DLCO/VA ratio(p = 0.03 and p = 0.005, respectively). Lung volumes of the CPFE group had significantly higher VC(p = 0.017), FRC (p < 0.001), RV(p < 0.001), RV/TLC(p < 0.001), and TLC(p < 0.001). There were significant correlations between emphysema scores and FVC (L)(p = 0.01), FEV1/FVC(p = 0.001), DLCO (p = 0.003), VC(p = 0.014), FRC (L)(p < 0.001), RV(p < 0.001), TLC(p < 0.001), and RV/TLC (p < 0.001). Mortality rates were comparable between the two groups. CPI (p = 0.02) and sPAP (p = 0.01) were independent predictors of mortality in patients with CPFE.ConclusionsThe presence and severity of emphysema affects pulmonary function in IPF. Patients with CPFE have reduced diffusion capacity, more severe air trapping, worse muscle weakness, more severe exercise desaturation, and pulmonary hypertension. CPI and pulmonary hypertension are two independent risk factors for mortality in subjects with CPFE.  相似文献   
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