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81.
82.
Reliable chemical sensors with high selectivity and sensitivity toward specific target molecules require rational synthesis of receptors, in-depth characterization of their complexation abilities and highly efficient transduction of the molecular recognition event. Here we report a steady-state and time-resolved fluorescence investigation of EtQxBox, a fluorescent conformationally blocked quinoxaline-based cavitand, aimed at assessing its selectivity toward aromatic versus non-aromatic analytes in solution. Fluorescence quenching of the EtQxBox in acetone is observed at increasing concentration of both aromatic (i.e. benzonitrile) and aliphatic (i.e. acetonitrile) compounds. The combination with fluorescence lifetime measurements permits to discriminate the predominantly static quenching of the aromatic analyte, due to non-fluorescent host–guest complex formation, from the mostly dynamic quenching of the non-aromatic compound, resulting from aspecific diffusive collisions between the fluorophore and the quencher. The equilibrium association constants for both the complexes have been estimated using Stern–Volmer model.

We investigate the role of combined static and dynamic quenching in fluorescence transduction of benzonitrile and acetonitrile complexation by a rigid quinoxaline-based cavitand.  相似文献   
83.
Journal of Thrombosis and Thrombolysis - To compare age at 1st ischaemic stroke (IS) in a cohort of juvenile (<?46 years of age) IS patients evaluated for the rs1801133...  相似文献   
84.
Since the dawn of medicine, scientists have carefully observed, modeled and interpreted the human body to improve healthcare. At the beginning there were drawings and paintings, now there is three-dimensional modeling. Moving from two-dimensional cultures and towards complex and relevant biomaterials, tissue-engineering approaches have been developed in order to create three-dimensional functional mimics of native organs. The bone marrow represents a challenging organ to reproduce because of its structure and composition that confer it unique biochemical and mechanical features to control hematopoiesis. Reproducing the human bone marrow niche is instrumental to answer the growing demand for human erythrocytes and platelets for fundamental studies and clinical applications in transfusion medicine. In this review, we discuss the latest culture techniques and technological approaches to obtain functional platelets and erythrocytes ex vivo. This is a rapidly evolving field that will define the future of targeted therapies for thrombocytopenia and anemia, but also a long-term promise for new approaches to the understanding and cure of hematologic diseases.  相似文献   
85.
Chronic hepatitis C virus (HCV) infection is the principal etiology of cirrhosis and, ultimately, hepatocellular carcinoma (HCC). At present, approximately 71 million people are chronically infected with HCV, and 10%–20% of these are expected to develop severe liver complications throughout their lifetime. Scientific evidence has clearly shown the causal association between miRNAs, HCV infection and HCC. Although it is not completely clear whether miRNA dysregulation in HCC is the cause or the consequence of its development, variations in miRNA patterns have been described in different liver diseases, including HCC. Many studies have analyzed the importance of circulating miRNAs and their effect on cell proliferation and apoptosis. In this Review, we aim to summarize current knowledge on the association between miRNA, HCV and HCC from a diagnostic point of view, and also the potential implications for therapeutic approaches.  相似文献   
86.
The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC.  相似文献   
87.
Journal of Interventional Cardiac Electrophysiology - Implantable cardioverter defibrillators (ICD) are widely accepted therapy in children and adolescents who are survivors of cardiac arrest or...  相似文献   
88.
We report on 14 children (seven boys, seven girls) with chronic idiopathic thrombocytopenic purpura (ITP) refractory to multiple treatments, who were given a short-term therapy (range between 6 and 10 weeks) with high doses of cyclosporin A (CyA) (median, 10 mg/kg/d). Six patients experienced adverse events and one developed severe systemic mycosis during therapy. A complete response (CR) was observed in four patients and a partial response (PR) in three patients. Only the four CR patients, who were all girls, had a sustained response. These data suggest that CyA may be effective in some children with chronic symptomatic ITP.  相似文献   
89.
Summary In this study, we evaluated in normal subjects, insulin-dependent (IDD) and non-insulin-dependent (NIDD) diabetics, the diurnal urinary C-peptide excretion rate (CPR-U) and its relationship to serum C-peptide concentration and glucose:C-peptide molar ratio, and to the common parameters of metabolic control. The CPR-U (and CPR-U/g creatinine) were significantly lower in IDD and higher in NIDD compared to control subjects. Moreover, a good and significant correlation with serum C-peptide concentrations and the glucose:C-peptide ratio in diabetic subjects as well as in controls and diabetics considered together was found. A slight but significant correlation was present in diabetic subjects between CPR-U and body mass index (r=0.45), 24-h glycosuria (r=−0.36), HbA1 levels (r=−0.31), post-prandial glucose concentrations (r=−0.26) and per cent glucose variation after each meal (r=−0.34). No differences were found in CPR-U and the degree of metabolic control between obese and non-obese NIDD. In conclusion, CPR-U may be a useful and simple method of defining the secretory activity of the B-cell. Metabolic control in diabetics is slightly correlated to the degree of B-cell function as evaluated by the diurnal excretion rate of C-peptide in urine. Part of this paper was presented at the National Meeting of the Italian Diabetes Association, Bari, May 27–29, 1982.  相似文献   
90.
We have previously shown that the life cycles of several viruses are influenced by host-cell redox states. Reports of the antioxidant activities of the plant polyphenol resveratrol (RV) prompted us to investigate its effects on influenza virus replication in vitro and in vivo. We found that RV strongly inhibited the replication of influenza virus in MDCK cells but that this activity was not directly related to glutathione-mediated antioxidant activity. Rather, it involved the blockade of the nuclear-cytoplasmic translocation of viral ribonucleoproteins and reduced expression of late viral proteins seemingly related to the inhibition of protein kinase C activity and its dependent pathways. RV also significantly improved survival and decreased pulmonary viral titers in influenza virus-infected mice. No toxic effects were observed in vitro or in vivo. That RV acts by inhibiting a cellular, rather than a viral, function suggests that it could be a particularly valuable anti-influenza drug.  相似文献   
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