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Hepatitis C virus (HCV) chronic infection is associated with fibrosis progression, end-stage liver complications and HCC. Not surprisingly, HCV infection is a leading cause of liver-related morbidity and mortality worldwide. After sustained virological response (SVR), the risk of developing hepatocellular carcinoma is not completely eliminated in patients with established cirrhosis or with advanced fibrosis. Therefore, lifelong surveillance is currently recommended. This strategy is likely not universally cost-effective and harmless, considering that not all patients with advanced fibrosis have the same risk of developing HCC. Factors related to the severity of liver disease and its potential to improve after SVR, the molecular and epigenetic changes that occur during infection and other associated comorbidities might account for different risk levels and are likely essential for identifying patients who would benefit from screening programs after SVR. Efforts to develop predictive models and risk calculators, biomarkers and genetic panels and even deep learning models to estimate the individual risk of HCC have been made in the direct-acting antiviral agents era, when thousands of patients with advanced fibrosis and cirrhosis have reached SVR. These tools could help to identify patients with very low HCC risk in whom surveillance might not be justified. In this review, factors affecting the probability of HCC development after SVR, the benefits and risks of surveillance, suggested strategies to estimate individualized HCC risk and the current evidence to recommend lifelong surveillance are discussed.  相似文献   
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A recently discovered variant in the prothrombin gene (20210A) has been found in approximately 5–10% of patients with venous thromboembolism. It has been shown that patients with this variant present with high levels of prothrombin in plasma and this is maintained to be the most likely mechanism by which the risk of thrombosis is increased. We have evaluated prothrombin antigen levels in 50 carriers of the 20210A allele and compared with non-carriers. 327 subjects were subdivided according to deficiency status and previous thrombosis. 30 symptomatic and 20 asymptomatic carriers had increased mean prothrombin levels as compared to symptomatic ( n  = 178) or asymptomatic ( n  = 99) non-carriers. The percentage of subjects with prothrombin levels above cut-off values of 1.15 u/ml or 1.30 u/ml was significantly higher in carriers of the prothrombin variant as compared to non-carriers, regardless of a previous thrombosis. However, among non-carriers the percentage of those with prothrombin levels above cut-off values was significantly higher in the group of symptomatic as compared to asymptomatic individuals. In conclusion, increased prothrombin antigen levels, as detected by a specific ELISA, were found among 50 symptomatic and asymptomatic carriers of the 20210A prothrombin variant as well as among a large group of symptomatic non-carriers. The data are in agreement with those found by using functional tests for the determination of prothrombin levels in these patients.  相似文献   
75.
A good night's sleep is often more elusive as we age, because the prevalence of insomnia in older people is high. Insufficient sleep can have important effects on daytime function by increasing the need to nap, reducing cognitive ability including attention and memory, slowing response time, adversely affecting relationships with friends and family, and contributing to a general sense of being unwell. However, rather than aging per se, circadian rhythm shifts, primary sleep disorders, comorbid medical/psychiatric illnesses, and medication use cause sleep difficulties in older people, which psychosocial factors may also affect. Clinicians should ask elderly patients about satisfaction with sleep. Any sleep complaints warrant careful evaluation of contributing factors and appropriate treatment.  相似文献   
76.
Limited information is available on the efficacy of cryoablation in the coronary venous system in humans. A patient with a lateral accessory pathway was referred to our center after several unsuccessful endocardial and epicardial (within the coronary sinus) attempts using standard radiofrequency energy. Ablation was subsequently performed successfully by applying cryoenergy distally into the coronary sinus, using a temperature of -50 degrees C and a freezing application time of 45 s. There were no complications. Angiography of the left coronary circumflex artery and coronary venous system was performed at 12 months follow-up using cardiac multislice computed tomography, and no coronary stenosis or anatomic anomaly was found. Neither pre-excitation or any arrhythmia recurred during follow-up. This experience suggests that ablating in the distal coronary sinus can be safely performed using cryoenergy.  相似文献   
77.
Recent studies have suggested that sleep is associated with IQ measures in children, but the underlying mechanism remains unknown. An association between sleep spindles and IQ has been found in adults, but only two previous studies have explored this topic in children. The goal of this study was to examine whether sleep spindle frequency, amplitude, duration and/or density were associated with performance on the perceptual reasoning, verbal comprehension, working memory, and processing speed subscales of the Wechsler Intelligence Scale for Children-IV (WISC-IV). We recruited 29 typically developing children 7–11 years of age. We used portable polysomnography to document sleep architecture in the natural home environment and evaluated IQ. We found that lower sleep spindle frequency was associated with better performance on the perceptual reasoning and working memory WISC-IV scales, but that sleep spindle amplitude, duration and density were not associated with performance on the IQ test.  相似文献   
78.
BTLA (B- and T-lymphocyte attenuator) is a prominent co-receptor that is structurally and functionally related to CTLA-4 and PD-1. In T cells, BTLA inhibits TCR-mediated activation. In B cells, roles and functions of BTLA are still poorly understood and have never been studied in the context of B cells activated by CpG via TLR9. In this study, we evaluated the expression of BTLA depending on activation and differentiation of human B cell subsets in peripheral blood and lymph nodes. Stimulation with CpG upregulated BTLA, but not its ligand: herpes virus entry mediator (HVEM), on B cells in vitro and sustained its expression in vivo in melanoma patients after vaccination. Upon ligation with HVEM, BTLA inhibited CpG-mediated B cell functions (proliferation, cytokine production, and upregulation of co-stimulatory molecules), which was reversed by blocking BTLA/HVEM interactions. Interestingly, chemokine secretion (IL-8 and MIP1β) was not affected by BTLA/HVEM ligation, suggesting that BTLA-mediated inhibition is selective for some but not all B cell functions. We conclude that BTLA is an important immune checkpoint for B cells, as similarly known for T cells.  相似文献   
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