Summary
Background
Transient elastography is a non‐invasive method for staging liver fibrosis. The meta‐analysis using the hierarchical models to evaluate the diagnostic accuracy of transient ...elastography for the staging of liver fibrosis in patients with chronic hepatitis B was rarely reported.
Aim
A meta‐analysis using the hierarchical models was performed to assess transient elastography for diagnosing and stage liver fibrosis in patients with chronic hepatitis B.
Methods
Electronic databases were searched and studies were identified to assess the diagnostic accuracy of transient elastography in CHB patients for staging fibrosis F ≥ 2, F ≥ 3 and F = 4 with liver biopsy as a reference standard. The hierarchical summary receiver operating characteristic curve and the bivariate models were performed to evaluate the diagnostic accuracy of transient elastography, and meta‐regression analyses were performed to explore the heterogeneity. The quality Assessment of Diagnostic Accuracy Studies‐2 tool was used to assess the quality of studies.
Results
Twenty‐seven studies with a total of 4386 patients were included in the meta‐analysis. The summary sensitivity of transient elastography for staging fibrosis F ≥ 2, F ≥ 3 and F = 4 was 0.806 (95% CI, 0.756–0.847), 0.819 (95% CI, 0.748–0.874) and 0.863 (95% CI, 0.818–0.898), respectively, and the summary specificity was 0.824 (95% CI, 0.761–0.873), 0.866 (95% CI, 0.824–0.899) and 0.875 (95% CI, 0.840–0.903), respectively. The corresponding area under the summary receiver operating characteristic curve was 0.88 (95% CI, 0.85–0.91), 0.91 (95% CI, 0.88–0.93) and 0.93 (95% CI, 0.91–0.95), respectively. Meta‐regression showed that patient age contributed to heterogeneity.
Conclusions
Transient elastography performs well to diagnose liver fibrosis in patients with chronic hepatitis B, which may reduce the use of liver biopsy.
A number of patient-specific and leukemia-associated factors are related to the poor outcome in older patients with acute myeloid leukemia (AML). However, comprehensive studies regarding the impact ...of genetic alterations in this group of patients are limited. In this study, we compared relevant mutations in 21 genes between AML patients aged 60 years or older and those younger and exposed their prognostic implications. Compared with the younger patients, the elderly had significantly higher incidences of PTPN11, NPM1, RUNX1, ASXL1, TET2, DNMT3A and TP53 mutations but a lower frequency of WT1 mutations. The older patients more frequently harbored one or more adverse genetic alterations. Multivariate analysis showed that DNMT3A and TP53 mutations were independent poor prognostic factors among the elderly, while NPM1 mutation in the absence of FLT3/ITD was an independent favorable prognostic factor. Furthermore, the status of mutations could well stratify older patients with intermediate-risk cytogenetics into three risk groups. In conclusion, older AML patients showed distinct genetic alterations from the younger group. Integration of cytogenetics and molecular mutations can better risk-stratify older AML patients. Development of novel therapies is needed to improve the outcome of older patients with poor prognosis under current treatment modalities.
MicroRNAs are a class of small, non‐coding RNAs that can negatively regulate protein‐coding genes, and are associated with almost all known physiological and pathological processes, especially ...cancer. The number of studies documenting miRNA expression patterns in malignancy continues to expand rapidly, with continuously gained critical information regarding how aberrantly expressed miRNAs may contribute to carcinogenesis. miRNAs can influence cancer pathogenesis, playing a potential role as either oncogenes or tumour suppressors. Recently, several miRNAs have been reported to exert different regulatory functions in oesophageal cancer – the carcinoma typically arising from the epithelial lining of the oesophagus. These miRNAs also have potential clinical applications towards developing biomarkers or targets for possible use in diagnosis or therapy in oesophageal cancer. In this review, we have summarized the two (oncogenic or tumour suppressive) roles of miRNAs here, and their applications as potential biomarkers or therapeutic targets, which may illuminate future treatment for oesophageal cancer.
Summary Objective Disruptions of extracellular matrix (ECM) homeostasis are key events in the pathogenesis of osteoarthritis (OA). MicroRNA-140 (miRNA-140) is expressed specifically in cartilage and ...regulates ECM-degrading enzymes. Our objective in this study was to determine if intra-articular injection of miRNA-140 can attenuate OA progression in rats. Design miRNA-140 levels in human normal and OA cartilage derived chondrocytes and synovial fluid were assessed by polymerase chain reaction (PCR). After primary human chondrocytes were transfected with miRNA-140 mimic or inhibitor, PCR and western blotting were performed to quantify Collagen II, MMP-13, and ADAMTS-5 expression. An OA model was induced surgically in rats, and subsequently treated with one single intra-articular injection of miRNA-140 agomir. At 4, 8, and 12 weeks after surgery, OA progression were evaluated macroscopically, histologically, and immunohistochemically in these rats. Results miRNA-140 levels were significantly reduced in human OA cartilage derived chondrocytes and synovial fluid compared with normal chondrocytes and synovial fluid. Overexpressing miRNA-140 in primary human chondrocytes promoted Collagen II expression and inhibited MMP-13 and ADAMTS-5 expression. miRNA-140 levels in rat cartilage were significantly higher in the miRNA-140 agomir group than in the control group. Moreover, behavioural scores, chondrocyte numbers, cartilage thickness and Collagen II expression levels in cartilage were significantly higher, while pathological scores and MMP-13 and ADAMTS-5 expression levels were significantly lower in the miRNA-140 agomir group than in the control group. Conclusion Intra-articular injection of miRNA-140 can alleviate OA progression by modulating ECM homeostasis in rats, and may have potential as a new therapy for OA.
Microbial life inhabits deeply buried marine sediments, but the extent of this vast ecosystem remains poorly constrained. Here we provide evidence for the existence of microbial communities in ∼40° ...to 60°C sediment associated with lignite coal beds at ∼1.5 to 2.5 km below the seafloor in the Pacific Ocean off Japan. Microbial methanogenesis was indicated by the isotopic compositions of methane and carbon dioxide, biomarkers, cultivation data, and gas compositions. Concentrations of indigenous microbial cells below 1.5 km ranged from <10 to ∼104 cells cm–3. Peak concentrations occurred in lignite layers, where communities differed markedly from shallower subseafloor communities and instead resembled organotrophic communities in forest soils. This suggests that terrigenous sediments retain indigenous community members tens of millions of years after burial in the seabed.
Nitrification is a series of processes that oxidizes ammonia to nitrate, which contributes to hypoxia development in coastal oceans, especially in eutrophicated regions. The nitrification rate of ...bulk water (NRb) and particle free water (NRpf, particle > 3 μm eliminated) were determined along the Chang Jiang River plume in August 2011 by nitrogen isotope tracer technique. Measurements of dissolved oxygen (DO), community respiration rate (CR), nutrients, dissolved organic nitrogen (DON), total suspended matter (TSM), particulate organic carbon/nitrogen (POC / PON), acid-leachable iron and manganese on suspended particles and both archaeal and β-proteobacterial ammonia monooxygenase subunit A gene (amoA) abundance on size-fractioned particles (> 3 μm and 0.22–3 μm) were conducted. The NRb ranged from undetectable up to 4.6 μmol L−1 day−1, peaking at a salinity of ~ 29. NRb values were positively correlated with ammonium concentration, suggesting the importance of substrate in nitrification. In the river mouth and the inner plume, NRb was much higher than NRpf, indicating that the nitrifying microorganism is mainly particle associated, which was supported by its significant correlation with amoA gene abundance and TSM concentration. The estimated oxygen demands of nitrification accounted for 0.32 to 318% of CR, in which 50% samples demanded more oxygen than that predicted by by the Redfield model (23%), indicating that oxygen might not be the sole oxidant though DO was sufficient (> 58 μmol kg−1) throughout the observation period. The excess nitrification-associated oxygen demand (NOD) showed a tendency to occur at lower DO samples accompanied by higher acid-leachable Fe / Mn, which implied reactive Fe3+ / Mn4+ may play a role as oxidant in the nitrification process. Stoichiometric calculation suggested that reactive Fe on particles was 10 times the oxidant demand required to complete ammonia oxidation in the entire plume. The potential involvement of reactive iron and manganese in the nitrification process in oxygenated water further complicated nitrogen cycling in the turbid river plume.
In January 2013, Beijing experienced several serious haze events. To achieve a better understanding of the characteristics, sources and processes of aerosols during this month, an Aerodyne ...high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed at an urban site between 1 January and 1 February 2013 to obtain the size-resolved chemical composition of non-refractory submicron particles (NR-PM1). During this period, the mean measured NR-PM1 mass concentration was 89.3 ± 85.6 μg m−3, and it peaked at 423 μg m−3. Positive matrix factorization (PMF) differentiated the organic aerosol into five components, including a highly oxidized, low-volatility oxygenated organic aerosol (LV-OOA), a less oxidized, semi-volatile oxygenated OA (SV-OOA), a coal combustion OA (CCOA), a cooking-related OA (COA), and a hydrocarbon-like OA (HOA), which on average accounted for 28%, 26%, 15%, 20% and 11% of the total organic mass, respectively. A detailed comparison between the polluted days and unpolluted days found many interesting results. First, the organic fraction was the most important NR-PM1 species during the unpolluted days (58%), while inorganic species were dominant on polluted days (59%). The OA composition also experienced a significant change; it was dominated by primary OA (POA), including COA, HOA and CCOA, on unpolluted days. The contribution of secondary OA (SOA) increased from 35% to 63% between unpolluted and polluted days. Second, meteorological effects played an important role in the heavy pollution in this month and differed significantly between the two types of days. The temperature and relative humidity (RH) were all increased on polluted days and the wind speed and air pressure were decreased. Third, the diurnal variation trend in NR-PM1 species and OA components showed some differences between the two types of days, and the OA was more highly oxidized on polluted days. Fourth, the effects of air masses were significantly different between the two types of days; air was mainly transported from contaminated areas on the polluted days. The comparison also found that the aerosol was more acidic on polluted days. Additionally, the variation trends of the mass concentration and mass fractions of NR-PM1 species and OA components were more dramatic when the NR-PM1 mass loading was at a higher level. The serious pollution observed in this month can be attributed to the synergy of unfavorable meteorological factors, the transport of air masses from high-pollution areas, emission by local sources, and other factors.
The Coexistence Approach was established by Mosbrugger and Utescher (1997) as a plant-based method to reconstruct palaeoclimate by considering recent climatic distribution ranges of the nearest ...living relatives of each fossil taxon. During its existence for over more than 15years, its basics have been tested and reviewed in comparison with other terrestrial and marine climate reconstruction techniques and climate modelling data. However, some controversies remain about its underlying data or its applicability in general.
In view of these controversies this paper discusses the power and limitations of the Coexistence Approach by summarising past results and new developments. We give insights into the details and problems of each step of the application from the assignment of the fossil plant to the most suitable nearest living relative, the crucial consideration of the usefulness of specific taxa towards their climatic values and the correct interpretation of the software-based suggested palaeoclimatic intervals. Furthermore, we reflect on the fundamental data integrated in the Coexistence Approach by explaining different concepts and usages of plant distribution information and the advantages and disadvantages of modern climatic maps. Additionally, we elaborate on the importance of continually updating the information incorporated in the database due to new findings in e.g., (palaeo-)botany, meteorology and computer technology.
Finally, for a transparent and appropriate use, we give certain guidelines for future applications and emphasize to users how to carefully consider and discuss their results. We show the Coexistence Approach to be an adaptive method capable of yielding palaeoclimatic and palaeoenvironmental information through time and space.
•New insight in the application of the Coexistence Approach is discussed.•15-year experience and results of this method are summarised.•Power and limits of the method are specified.•Necessary databases are reflected upon new scientific knowledge.•Guidelines for critical reconstruction of palaeoclimate are suggested.
Two-dimensional (2D) materials have been studied extensively as monolayers, vertical or lateral heterostructures. To achieve functionalization, monolayers are often patterned using soft lithography ...and selectively decorated with molecules. Here we demonstrate the growth of a family of 2D materials that are intrinsically patterned. We demonstrate that a monolayer of PtSe
can be grown on a Pt substrate in the form of a triangular pattern of alternating 1T and 1H phases. Moreover, we show that, in a monolayer of CuSe grown on a Cu substrate, strain relaxation leads to periodic patterns of triangular nanopores with uniform size. Adsorption of different species at preferred pattern sites is also achieved, demonstrating that these materials can serve as templates for selective self-assembly of molecules or nanoclusters, as well as for the functionalization of the same substrate with two different species.