Integrative analysis of dysregulated lncRNA-associated ceRNA network reveals potential lncRNA biomarkers for human hepatocellular carcinoma

Background Hepatocellular carcinoma (HCC) is an aggressive cancer with a poor prognosis and a high incidence. The molecular changes and novel biomarkers of HCC need to be identified to improve the diagnosis and prognosis of this disease. We investigated the current research concentrations of HCC and identified the transcriptomics-related biomarkers of HCC from The Cancer Genome Atlas (TGCA) database. Methods We investigated the current research concentrations of HCC using literature metrology analysis for studies conducted from 2008 to 2018. We identified long noncoding RNAs (lncRNAs) that correlated with the clinical features and survival prognoses of HCC from The Cancer Genome Atlas (TGCA) database. Differentially expressed genes (lncRNAs, miRNAs, and mRNAs) were also identified by TCGA datasets in HCC tumor tissues. A lncRNA competitive endogenous RNA (ceRNA) network was constructed from lncRNAs based on intersected lncRNAs. Survival times and the association between the expression levels of the key lncRNAs of the ceRNA network and the clinicopathological characteristics of HCC patients were analyzed using TCGA. Real-time polymerase chain reaction (qRT-PCR) was used to validate the reliability of the results in tissue samples from 20 newly-diagnosed HCC patients. Results Analysis of the literature pertaining to HCC research revealed that current research is focused on lncRNA functions in tumorigenesis and tumor development. A total of 128 HCC dysregulated lncRNAs were identified; 66 were included in the co-expressed ceRNA network. We analyzed survival times and the associations between the expression of 66 key lncRNAs and the clinicopathological features of the HCC patients identified from TCGA. Twenty-six lncRNAs were associated with clinical features of HCC (P < 0.05) and six key lncRNAs were associated with survival time (log-rank test P < 0.05). Six key lncRNAs were selected for the validation of their expression levels in 20 patients with newly diagnosed HCC using qRT-PCR. Consistent fold changes in the trends of up and down regulation between qRT-PCR validation and TCGA proved the reliability of our bioinformatics analysis. Conclusions We used integrative bioinformatics analysis of the TCGA datasets to improve our understanding of the regulatory mechanisms involved with the functional features of lncRNAs in HCC. The results revealed that lncRNAs are potential diagnostic and prognostic biomarkers of HCC

Comparison of the Shutdown Transitions of the Full-Flow Pump and Axial-Flow Pump

In this study, a comparative analysis of the shutdown transitions of a full-flow pump and an axial-flow pump was carried out through numerical simulation and model tests. The UDF method was used to achieve control of the impeller rotational speed during shutdown. The results show that during the shutdown transition, the rate of decline of rotational speed, flow rate, and torque of the axial-flow pump are greater than those of the full-flow pump, so the axial-flow pump stops faster than the full-flow pump. The axial force of the axial-flow pump is significantly lower than that of the full-flow pump, and the maximum value of the radial force of the axial-flow pump is approximately 1.14 times that of the full-flow pump. Due to the influence of the clearance backflow vortex, the impeller inlet and outlet of the full-flow pump generate clearance backflow vortices in the near-wall area, resulting in the overall flow pattern of the impeller chamber being worse than that of the axial-flow pump and the hydraulic loss being greater than that of the axial-flow pump. The runaway speed and flow rate of the axial-flow pump are higher than those of the full-flow pump. Due to the influence of the clearance backflow, the range of the high entropy production rate at the suction side of the impeller of the full-flow pump is always larger than that of the axial-flow pump. The research results in this paper can provide theoretical support for the selection and operation of pumps in large low-head pumping stations

Dye-sensitized solar cells employing polymers

Dye-sensitized solar cells (DSSCs) are of interest due to their potential use as inexpensive and environmentally friendly photovoltaic (PV) devices with acceptable power conversion efficiency (PCE). Platinum (Pt) metal is, traditionally, the preferred material for the counter electrode (CE) component of DSSCs, however, further development of iodide/triiodide (I−/I3−) based liquid-electrolyte DSSCs using Pt remains challenging due to the high cost of this scarce metal and its susceptibility to corrosion. Additional concerns include solvent leakage and low chemical stability resulting from volatile liquid electrolyte used in DSSCs. In order to counteract this issue, polymer electrolytes or hole-transporters with higher mobilities are employed as a replacement for liquid electrolytes. In this regard, polymers can serve as efficient CE materials by replacing the platinized electrode in liquid-electrolyte DSSCs, while also substituting for the liquid electrolytes as polymer electrolytes or hole-transporters in solid-state or quasi solid-state DSSCs. Considering the fragility and shape restrictions of glass substrates, polymer substrates may also be used to replace rigid glass substrates, providing more flexible DSSCs. Herein, applications of the polymers as cell components (CEs, polymer electrolytes or hole-transporter, and plastic substrates) in DSSCs are discussed, with special focus on the role that polymers play in DSSCs and widely accepted reports of PV performance. The current understanding of the factors and strategies involved in improving the performance of polymers in DSSCs are reviewed and analyzed. In addition, the benefits, challenges and potential utility of polymers for use in DSSCs are assesse5914

Using the combined gene approach and multiple analytical methods to improve the phylogeny and classification of Bombus (Hymenoptera, Apidae) in China

Bumble bees are vital to our agro-ecological system, with approximately 250 species reported around the world in the single genus Bombus. However, the health of bumble bees is threatened by multiple factors: habitat loss, climate change, pesticide use, and disease caused by pathogens and parasites. It is therefore vitally important to have a fully developed phylogeny for bumble bee species as part of our conservation efforts. The purpose of this study was to explore the phylogenetic relationships of the dominant bumble bees on the Tibetan plateau and in northern China as well as their placement and classification within the genus Bombus. The study used combined gene analysis consisting of sequence fragments from six genes, 16S rRNA, COI, EF-1α, Argk, Opsin and PEPCK, and the phylogenetic relationships of 209 Bombus species were explored. Twenty-six species, including 152 gene sequences, were collected from different regions throughout China, and 1037 gene sequences representing 183 species were obtained from GenBank or BOLD. The results suggest that the 209 analyzed species belong to fifteen subgenera and that most of the subgenera in Bombus are monophyletic, which is in accordance with conventional morphology-based classifications. The phylogenetic trees also show that nearly all subgenera easily fall into two distinct clades: short-faced and long-faced. The study is the first to investigate the phylogenetic placement of Bombus turneri (Richards), Bombus opulentus Smith, Bombus pyrosoma Morawitz, Bombus longipennis Friese, Bombus minshanensis Bischoff, and Bombus lantschouensis Vogt, all of which are widely distributed throughout different regions of China. The knowledge and understanding gained from the findings can provide a molecular basis to accurately classify Bombus in China and to define strategies to conserve biodiversity and promote pollinator populations

Vortex beam generation with variable topological charge based on a spiral slit

We propose a vortex beam generator based on a nanometer spiral slit and explore the propagation rule of the topological charge. Compared to the common methods of generation of a vortex beam with a fixed topological charge, the optical vortex generated by the proposed vortex beam generator has the topological charge varying with the propagation distance. The value of topological charge can be modulated by the geometric charge of the spiral slit and the propagation distance. Theoretical analysis predicts the variation rule of the topological charge of vortex beam in the near field, and numerical simulations and experimental measurement verify the proposed scheme. Discussion on the shape and structure of the spiral slit is also presented. This work provides the theoretical foundation for the generation of a vortex field with variable topological charge. The simple geometry of the vortex beam generator and the flexible modulation of the topological charge must inspire applications of the vortex beam

Standardisation of Troponin I Measurements: an Update

Standardization of cardiac troponin I (cTnI) measurement is important because of the central role for diagnosos of myocardial infarction. In blood, cTnI is present as a heterogeneous mixture of differnent molecular species. The analytical problem caused by this microheterogeneity may be circumvented by recognition of a unique, invariant part of the molecule that is common to all components of the mixture. Antibodies used for development of cTnI assays should selectively recognize epitopes within this invariant part, leading to a consequential increase on the homogeneity of immonuassay reactivity. This should be associated with the use of a reference material (RM) that represents the natural and major antigen in blood after tissue release, i.e. the troponin complex. Although a primary RM for cTnI is available, studies indicate that cTnI assays remain without harmony after recalibration using this material. In order to achieve closer comparability of cTnI values between assays, the use of a secondary RM, consisting of a panel of human serum pools, is proposed for use by manufacturers to calibrate their assays. To assign true cTnI concentration values to this secondary RM, establishment of a reference measurement procedure for cTnI is required. A practical approach to the development of a reference procedure could be to design an immunochemical assay with well-characterized specificity to the invariant part of the cTnI molecule and calibrated using the primary RM.JRC.D.2-Reference material

Evaluation of standardization capability of current cardiac troponin I assays by a correlation study: results of an IFCC pilot project

Background: As a part of an International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) project to prepare a commutable reference material for cardiac troponin I (cTnI), a pilot study evaluated current cTnI assays for measurement equivalence and their standardization capability. Methods: cTnI-positive samples collected from 90 patients with suspected acute myocardial infarction were assessed for method comparison by 16 cTnI commercial assays according to predefined testing protocols. Seven serum pools prepared from these samples were also assessed. Results: Each assay was assessed against median cTnI concentrations measured by 16 cTnI assays using Passing-Bablok regression analysis of 79 patient samples with values above each assay’s declared detection limit. We observed a 10-fold difference in cTnI concentrations for lowest to highest measurement results. After mathematical recalibration of assays, the between-assay variation for patient samples reduced on average from 40% to 22% at low cTnI concentration, 37%–20% at medium concentration, and 29%–14% at high concentration. The average reduction for pools was larger at 16%, 13% and 7% for low, medium and high cTnI concentrations, respectively. Overall, assays demonstrated negligible bias after recalibration (y-intercept: –1.4 to 0.3 ng/L); however, a few samples showed substantial positive and/or negative differences for individual cTnI assays. Conclusions: All of the 16 commercial cTnI assays evaluated in the study demonstrated a significantly higher degree of measurement equivalence after mathematical recalibration, indicating that measurement harmonization or standardization would be effective at reducing inter-assay bias. Pooled sera behaved similarly to individual samples in most assays.JRC.D.2-Standards for Innovation and sustainable Developmen

The Prevalence of Parasites and Pathogens in Asian Honeybees Apis cerana in China

Pathogens and parasites represent significant threats to the health and well-being of honeybee species that are key pollinators of agricultural crops and flowers worldwide. We conducted a nationwide survey to determine the occurrence and prevalence of pathogens and parasites in Asian honeybees, Apis cerana, in China. Our study provides evidence of infections of A. cerana by pathogenic Deformed wing virus (DWV), Black queen cell virus (BQCV), Nosema ceranae, and C. bombi species that have been linked to population declines of European honeybees, A. mellifera, and bumble bees. However, the prevalence of DWV, a virus that causes widespread infection in A. mellifera, was low, arguably a result of the greater ability of A. cerana to resist the ectoprasitic mite Varroa destructor, an efficient vector of DWV. Analyses of microbial communities from the A. cerana digestive tract showed that Nosema infection could have detrimental effects on the gut microbiota. Workers infected by N. ceranae tended to have lower bacterial quantities, with these differences being significant for the Bifidobacterium and Pasteurellaceae bacteria groups. The results of this nationwide screen show that parasites and pathogens that have caused serious problems in European honeybees can be found in native honeybee species kept in Asia. Environmental changes due to new agricultural practices and globalization may facilitate the spread of pathogens into new geographic areas. The foraging behavior of pollinators that are in close geographic proximity likely have played an important role in spreading of parasites and pathogens over to new hosts. Phylogenetic analyses provide insights into the movement and population structure of these parasites, suggesting a bidirectional flow of parasites among pollinators. The presence of these parasites and pathogens may have considerable implications for an observed population decline of Asian honeybees.ISSN:1932-620