What Links Chronic Kidney Disease and Ischemic Cardiomyopathy? A Comprehensive Bioinformatic Analysis Utilizing Bulk and Single-Cell RNA Sequencing Data with Machine Learning.

Chronic kidney disease (CKD) emerges as a substantial contributor to various cardiovascular disorders, including ischemic cardiomyopathy (ICM). However, the underlying molecular mechanisms linking CKD and ICM remain elusive. Our study aims to unravel these connections by integrating publicly available bulk and single-cell RNA sequencing (scRNA-seq) data. Expression profiles from two ICM datasets obtained from heart tissue and one CKD with Peripheral Blood Mononuclear Cell (CKD-PBMC) dataset were collected. We initiated by identifying shared differentially expressed genes (DEGs) between ICM and CKD. Subsequent functional enrichment analysis shed light on the mechanisms connecting CKD to ICM. Machine learning algorithms enabled the identification of 13 candidate genes, including AGRN, COL16A1, COL1A2, FAP, FRZB, GPX3, ITIH5, NFASC, PTN, SLC38A1, STARD7, THBS2, and VPS35. Their expression patterns in ICM were investigated via scRNA-seq data analysis. Notably, most of them were enriched in fibroblasts. COL16A1, COL1A2, PTN, and FAP were enriched in scar-formation fibroblasts, while GPX3 and THBS2 showed enrichment in angiogenesis fibroblasts. A Gaussian naïve Bayes model was developed for diagnosing CKD-related ICM, bolstered by SHapley Additive exPlanations interpretability and validated internally and externally. In conclusion, our investigation unveils the extracellular matrix's role in CKD and ICM interplay, identifies 13 candidate genes, and showcases their expression patterns in ICM. We also constructed a diagnostic model using 13 gene features and presented an innovative approach for managing CKD-related ICM through serum-based diagnostic strategies.

Toward understanding the interaction of shale gas-water-carbon nexus in Sichuan-Chongqing region based on county-level water security evaluation.

This study develops a comprehensive framework for understanding the interaction of shale gas-water-carbon nexus in Sichuan-Chongqing region. Within this framework, a county-level water security index (WSI) evaluation system is structured. Spatial autocorrelation model and spatial matching degree model are integrated to illustrate the spatial agglomeration characteristics of water security and the water-carbon relationship, respectively. The impacts of shale gas development on water security and carbon emissions are evaluated based on identification of shale well productivity. Results show that about 25.17% of counties with WSI < 0.4 (unsafe), especially in the eastern region. The central cities (such as Chengdu and Neijiang) should take active steps to reach a safety threshold (WSI ≥ 0.6). Population growth can accelerate water security deterioration through uncertainty analysis. Moreover, the spatial matching degree between WSI and carbon emissions in most cities is extremely poor (< 0.5), implying that these cities should optimize their energy structure and promote green transformation. Water used for shale gas extraction can hardly be ignored from a county-scale perspective, especially in Tongliang, Tongnan, and Jianyang. The future shale gas development would pose a threat to the regional climate.

A retrospective study about association of dynamic systemic immune-inflammation index (SII) with 180-day functional outcome after basal ganglia intracerebral hemorrhage.

Objectives: This study aimed to determine whether SII on different days of admission is associated with severity and 180-day functional outcomes after basal ganglia ICH. Methods: In this retrospective study, data on baseline CT imaging characteristics, mRS, hematoma volume, and laboratory variables were included. The SII and NLR, LMR, and PLR were calculated from laboratory data collected on admission day, day 1, and days 5-7. Both univariate and multivariable logistic regression analyses were used to assess the association between the SII and the outcome. The receiver operating characteristic (ROC) analysis and area under the curve (AUC) were also used to evaluate the ability of the SII to predict outcomes. Result: A total of 245 patients were enrolled in the study. On different days, the NLR, PLR, and SII were significantly lower in patients with favorable outcomes than in those with poor outcomes, and the volume of hemorrhage was positively correlated with the SII. These parameters were associated with outcomes in the univariate logistic regression. In the adjusted analyses, the SII and PLR were independent predictors of basal ganglia ICH outcomes. ROC analysis revealed that the SII showed a stronger ability to predict the 6-month outcomes of patients after basal ganglia ICH than the PLR on different days (AUC = 0.642, 0.804, 0.827 vs. 0.592, 0.725, 0.757; all P < 0.001). Conclusion: The SII independently and strongly predicts the outcome of basal ganglia ICH. A high SII was associated with poor 6-month outcomes in patients with basal ganglia ICH.

Increased plasma expression of a disintegrin and metalloproteinase with thrombospondin motifs like 4 in patients with idiopathic pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension.

Idiopathic pulmonary arterial hypertension (IPAH) and chronic thromboembolic pulmonary hypertension (CTEPH) can result in right heart failure. We aimed to evaluate the plasma protein levels of a disintegrin and metalloproteinase with thrombospondin motifs like 4 (ADAMTSL4) and its relationship with IPAH and CTEPH. Plasma ADAMTSL4 protein levels were measured using proteomics analysis in eight patients with IPAH and nine healthy controls. ADAMTSL4 levels in pulmonary tissues were assessed using bioinformatics tools. Protein expression of ADAMTSL4 in platelet-derived growth factor (PDGF)-BB-treated primary rat pulmonary arterial smooth muscle cells (PASMCs) was detected by Western blot. Plasma ADAMTSL4 concentrations were measured in 45 patients (15 with IPAH and 30 with CTEPH) using enzyme-linked immunosorbent assay (ELISA). Correlation between ADAMTSL4 levels and clinical parameters was evaluated. In patients with IPAH, the plasma levels of ADAMTSL4 protein were significantly higher than those in healthy controls (flod change [FC] 1.85, p < 0.05), and mRNA expression levels were significantly elevated (log FC 0.66, p < 0.05). The protein expression of ADAMTSL4 was significantly increased in PDGF-BB-treated PASMCs compared to that in the control grAoup (p < 0.05). Plasma ADAMTSL4 protein levels in patients with IPAH (4.71 ± 0.73 ng/mL, p < 0.01) and CTEPH (4.22 ± 0.66 ng/mL, p < 0.01) were higher than in healthy controls (3.01 ± 0.46 ng/mL). Plasma ADAMATL4 protein levels had a cutoff value of 3.55 ng/mL based on the receiver operator characteristic curve and were positively correlated with mean pulmonary artery pressure (mPAP) (r = 0.305, p < 0.05). In patients with IPAH and CTEPH, elevated plasma ADAMTSL4 levels were positively associated with mPAP.

Mineral Phase Reconstruction and Separation Behavior of Zinc and Iron from Zinc-Containing Dust.

Zinc-containing dust can be found in ironmaking and steelmaking, and it is an important secondary resource of zinc. Zinc-containing dust from an electric furnace was used as a raw material to study the phase transformation behavior of the dust using a calcification roasting process and the zinc-iron separation behavior by using ammonia leaching. The zinc-bearing dust was mixed with CaO and roasted to transform the zinc ferrite into zinc oxide. The results showed that increasing the calcium oxide to dust ratio could promote the conversion of zinc ferrite to zinc oxide. When the calcium oxide ratio reached 60%, the peak of zinc ferrite in the calcined-roasted product in the zinc-containing dust basically disappeared. As the temperature increased, the zinc oxide grains increased but were still smaller than 10 µm. The calcined-roasted product was crushed and ground, and the zinc was leached by ammonia. A zinc-iron recovery rate of 86.12% was achieved by the ammonia leaching. The leachate could be used for zinc extraction by electrolysis. The leaching residue was mainly calcium ferrate, which could be used in sintering production. The proposed process may achieve on-site recovery of zinc-containing dust in steel-making plants.

Controllable Exfoliation of MOF-Derived Van Der Waals Superstructure into Ultrathin 2D B/N Co-Doped Porous Carbon Nanosheets: A Superior Catalyst for Ambient Ammonia Electrosynthesis.

The electrocatalytic nitrogen reduction reaction (NRR) to synthesize NH3 under ambient conditions is a promising alternative route to the conventional Haber-Bosch process, but it is still a great challenge to develop electrocatalysts' high Faraday efficiency and ammonia yield. Herein, a facile and efficient exfoliation strategy to synthesize ultrathin 2D boron and nitrogen co-doped porous carbon nanosheets (B/NC NS) via a metal-organic framework (MOF)-derived van der Waals superstructure, is reported. The results of experiments and theoretical calculations show that the doping of boron and nitrogen can modulate the electronic structure of the adjacent carbon atoms; which thus, promotes the competitive adsorption of nitrogen and reduces the energy required for ammonia synthesis. The B/NC NS exhibits excellent catalytic performance and stability in electrocatalytic NRR, with a yield rate of 153.4 µg·h-1 ·mg-1 cat and a Faraday efficiency of 33.1%, which is better than most of the reported NRR electrocatalysts. The ammonia yield of B/NC NS can maintain 92.7% of the initial NRR activity after 48 h stability test. The authors' controllable exfoliation strategy using MOF-derived van der Waals superstructure can provide a new insight for the synthesis of other 2D materials.

The Adsorptive Separation of Ethylene from C2 Hydrocarbons by Metal-Organic Frameworks.

Separating ethylene (C2 H4 ) from the C2 hydrocarbons is of prime industrial importance for the process of high-purity C2 H4 as an essential raw material in the petrochemical industry. Due to their similar physicochemical properties, the separation of C2 H4 from the C2 hydrocarbons typically entails high-energy separation technologies such as cryogenic distillation and extraction. Alternatively, adsorption separation using metal-organic frameworks (MOFs) are low-energy separation technologies that manufacture high-purity gas under mild conditions. In this review, we summarized the recent advances in MOFs for the separation and purification of C2 H4 from the C2 hydrocarbons. The mechanisms underlying separating C2 H4 from the C2 hydrocarbons using MOFs are also highlighted. This review also discussed the major challenges and developments of MOFs to separate C2 H4 from the C2 hydrocarbons.

Removal of Sodium from Vanadium Tailings by Calcification Roasting in Reducing Atmosphere.

Vanadium tailings from vanadium extraction by a sodium roasting process are solid waste and cannot be used in sintering and ironmaking due to their high sodium content. In this paper, a calcification and reduction roasting process was proposed to remove sodium from vanadium tailings. The effects of Ca(OH)2 addition, reduction temperature, and roasting time on the sodium removal behavior and compression strength of pellets were studied. The addition of Ca(OH)2 and the reduction of iron oxides promoted the sodium-containing phases to transform to be simpler, which could enhance sodium removal. The sodium removal rate was up to 93.47% and the compression strength of the reduced products was 4497 N/P, and the metallized ratio of the product was higher than 70% under the optimal conditions: roasting at 1200 °C for 2 h with the Ca(OH)2 addition of 35%. The treated product after removing sodium can be recycled in the ironmaking process in a steel company.

Anti-Entry Activity of Natural Flavonoids against SARS-CoV-2 by Targeting Spike RBD.

COVID-19 is still a global public health concern, and the SARS-CoV-2 mutations require more effective antiviral agents. In this study, the antiviral entry activity of thirty-one flavonoids was systematically evaluated by a SARS-CoV-2 pseudovirus model. Twenty-four flavonoids exhibited antiviral entry activity with IC50 values ranging from 10.27 to 172.63 µM and SI values ranging from 2.33 to 48.69. The structure-activity relationship of these flavonoids as SARS-CoV-2 entry inhibitors was comprehensively summarized. A subsequent biolayer interferometry assay indicated that flavonoids bind to viral spike RBD to block viral interaction with ACE2 receptor, and a molecular docking study also revealed that flavonols could bind to Pocket 3, the non-mutant regions of SARS-CoV-2 variants, suggesting that flavonols might be also active against virus variants. These natural flavonoids showed very low cytotoxic effects on human normal cell lines. Our findings suggested that natural flavonoids might be potential antiviral entry agents against SARS-CoV-2 via inactivating the viral spike. It is hoped that our study will provide some encouraging evidence for the use of natural flavonoids as disinfectants to prevent viral infections.

Self-Terminating Surface Reconstruction Induced by High-Index Facets of Delafossite for Accelerating Ammonia Oxidation Reaction Involving Lattice Oxygen.

Ammonia (NH3 ) is a promising hydrogen (H2 ) carrier for future carbon-free energy systems, due to its high hydrogen content and easiness to be liquefied. Inexpensive and efficient catalysts for ammonia electro-oxidation reaction (AOR) are desired in whole ammonia-based energy systems. In this work, ultrasmall delafossite (CuFeO2 ) polyhedrons with exposed high-index facets are prepared by a one-step NH3 -assisted hydrothermal method, serving as AOR pre-catalysts. The high-index CuFeO2 facet is revealed to facilitate surface reconstruction into active Cu-doped FeOOH nanolayers during AOR processes in ammonia alkaline solutions, which is driven by the favorable Cu leaching and terminates as the 2p levels of internal lattice oxygen change. The reconstructed heterostructures of CuFeO2 and Cu-doped FeOOH effectively activate the dehydrogenation steps of NH3 and exhibit a potential improvement of 260 mV for electrocatalytic AOR at 10 mA cm-2 compared to the pre-restructured phase. Further, density functional theory (DFT) calculations confirm that a lower energy barrier of the rate-determining step (*NH3 to *NH2 ) is presented on high-index CuFeO2 facets covered with Cu-doped FeOOH nanolayers. Innovatively, lattice oxygen atoms in Fe-based oxides and oxyhydroxide are involved in the dehydrogenation steps of AOR as a proton acceptor, broadening the horizons for rational designs of AOR catalysts.

The Transition of Mg-Containing Phases and Recovery of NaCl in Molten Salt Chloride Slags at High Temperature.

The molten salt chlorination method is more suitable to produce TiCl4 using titanium-containing materials with high contents of CaO and MgO in China. However, there is a large amount of molten salt chloride slags generated from the molten salt chlorination process, which contains a variety of chlorides and is difficult to treat, often causing serious environmental problems such as direct piling or landfilling. A novel process was proposed to deal with molten salt chloride slags, and calcium chloride could be effectively removed by this process (as in our previous study). However, magnesium chloride is another impurity which can deteriorate the density and viscosity of the molten salt; it is often found in higher contents, and should be also removed from molten salt chloride slags to efficiently recycle NaCl in novel processes. Na2SiO3 is added to the molten salt chloride slags in the molten state to produce the Mg-containing solid phase, which could be separated with the molten NaCl in novel processes. Thus, the transition of Mg-containing phases and the recovery of NaCl in molten salt chloride slags at high temperature in a novel process were systematically investigated in this work, including thermodynamic analysis, the phase transition behavior of Mg-containing phases, NaCl recovery, etc. The removal rate of Mg was 99.56% when the molar ratio of MgCl2:Na2SiO3 was 1:1.5 at 1273 K and in a N2 atmosphere. The recovery rate of NaCl from the molten salt chlorination slag was 97.62% and the purity of NaCl obtained was 99.35 wt%, which could be used in the molten salt chlorination process.

Hub Genes Identification, Small Molecule Compounds Prediction for Atrial Fibrillation and Diagnostic Model Construction Based on XGBoost Algorithm.

Background: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and engenders significant global health care burden. The underlying mechanisms of AF is remained to be revealed and current treatment options for AF have limitations. Besides, a detection system can help identify those at risk of developing AF and will enable personalized management. Materials and Methods: In this study, we utilized the robust rank aggregation method to integrate six AF microarray datasets from the Gene Expression Omnibus database, and identified a set of differentially expressed genes between patients with AF and controls. Potential compounds were identified by mining the Connectivity Map database. Functional modules and closely-interacted clusters were identified using weighted gene co-expression network analysis and protein-protein interaction network, respectively. The overlapped hub genes were further filtered. Subsequent analyses were performed to analyze the function, biological features, and regulatory networks. Moreover, a reliable Machine Learning-based diagnostic model was constructed and visualized to clarify the diagnostic features of these genes. Results: A total of 156 upregulated and 34 downregulated genes were identified, some of which had not been previously investigated. We showed that mitogen-activated protein kinase and epidermal growth factor receptor inhibitors were likely to mitigate AF based on Connectivity Map analysis. Four genes, including CXCL12, LTBP1, LOXL1, and IGFBP3, were identified as hub genes. CXCL12 was shown to play an important role in regulation of local inflammatory response and immune cell infiltration. Regulation of CXCL12 expression in AF was analyzed by constructing a transcription factor-miRNA-mRNA network. The Machine Learning-based diagnostic model generated in this study showed good efficacy and reliability. Conclusion: Key genes involving in the pathogenesis of AF and potential therapeutic compounds for AF were identified. The biological features of CXCL12 in AF were investigated using integrative bioinformatics tools. The results suggested that CXCL12 might be a biomarker that could be used for distinguishing subsets of AF, and indicated that CXCL12 might be an important intermediate in the development of AF. A reliable Machine Learning-based diagnostic model was constructed. Our work improved understanding of the mechanisms of AF predisposition and progression, and identified potential therapeutic avenues for treatment of AF.

Mitochondria MicroRNA Spatial Imaging via pH-Responsive Exonuclease-Assisted AIE Nanoreporter.

Mitochondrial microRNAs (mitomiRs) critically orchestrate mitochondrial functions. Spatial imaging of mitomiRs is essential to understand its clinical value in diagnosis and prognosis. However, the direct monitoring of mitomiRs in living cells remains a key challenge. Herein, we report an AIE nanoreporter strategy for mitomiRs imaging in living cells through pH-controlled exonuclease (Exo)-assisted target cycle signal amplification. The AIE-labeled DNA detection probes are conjugated on Exo III encapsulated polymeric nanoparticles (NPs) via consecutive adenines (polyA). The amplified sensing functions are off during the cytoplasm delivery process, and it can be spatially switched from off to on when in the alkaline mitochondria (about pH 8) after triphenylphosphonium (TPP)-mediated mitochondrial targeting. Where the NPs degraded to release Exo III and cancer-specific mitomiRs hybridize with AIE-labeled DNA detection probes to expose the cleavage site of released Exo III, enabling spatially restricted mitomiRs imaging. The mitomiRs expression fluctuation was also realized. This study contributes to a facile strategy that could easily extend to a broad application for the understanding of mitomiRs-related pathological processes.

Pulmonary artery enlargement predicts poor survival in patients with COPD: A meta-analysis.

No previous meta-analysis has evaluated the relationship between pulmonary artery enlargement (PAE) measured by computed tomography (CT) and prognosis for patients with chronic obstructive pulmonary disease (COPD). Recently, several studies have suggested poor survival and reduced exercise capacity in COPD patients with PAE on CT scan, but there were conflicting results. We aimed to assess the prognostic value of PAE-CT in patients with COPD. Relevant studies were identified by searching major databases. Pooled outcomes were determined to assess the prognostic value of PAE-CT in COPD patients. Eighteen studies including 5694 participants were included. PAE indicated higher mortality in COPD patients (odds ratio [OR] = 3.06; 95% confidence interval [95% CI]: 1.76-5.32; p < 0.0001), shorter 6-minute walk distance (mean difference [MD] = -67.53 m; 95% CI: -85.98 to -49.08; p < 0.00001), higher pulmonary artery systolic pressure (MD = 15.65 mmHg; 95% CI: 13.20-18.11; p < 0.00001), longer length of hospital stay (MD = 2.92 days; 95% CI: 0.71-5.12; p = 0.009) and more severe symptom such as dyspnea (COPD Assessment Test MD = 3.14; 95% CI: 2.48-3.81; p < 0.00001). We also conducted a subgroup analysis regarding the lung function and blood gas analysis for a stable period and acute exacerbation of COPD patients. In conclusion, PAE is significantly associated with mortality, lower exercise tolerance, and poor quality of life in patients with COPD. PAE may serve as a novel imaging biomarker for risk stratification in patients with COPD in the future.

Microneedle-Based Device for Biological Analysis.

The collection and analysis of biological samples are an effective means of disease diagnosis and treatment. Blood sampling is a traditional approach in biological analysis. However, the blood sampling approach inevitably relies on invasive techniques and is usually performed by a professional. The microneedle (MN)-based devices have gained increasing attention due to their noninvasive manner compared to the traditional blood-based analysis method. In the present review, we introduce the materials for fabrication of MNs. We categorize MN-based devices based on four classes: MNs for transdermal sampling, biomarker capture, detecting or monitoring analytes, and bio-signal recording. Their design strategies and corresponding application are highlighted and discussed in detail. Finally, future perspectives of MN-based devices are discussed.

Endogenous MicroRNA Accurate Diagnostics to Guide Photothermal Therapy.

Developing an intelligent theranostic nanoplatform with satisfied diagnostic accuracy and therapeutic efficiency holds great promise for personalized nanomedicine. Herein, we constructed a smart nanodevice for the accurate diagnosis of endogenous cancer microRNA (miRNA) biomarkers and efficient photothermal therapy (PTT). The nanodevice was composed of polydopamine (PDA)-functionalized CuS nanosheets (CuS@PDA NSs) and three elaborate DNA hairpin probes (TDHPs). The CuS@PDA NSs acted as efficient delivery vehicles and photothermal agents. They provided a large surface area available for an efficient and facile loading of TDHPs and a high-fluorescence (FL) quenching performance to achieve an ultralow background signal. The intracellular miRNA triggered TDHPs to assemble into three-arm branched junction structures for a strong fluorescence recovery as output signals to discriminate cancer cells from normal cells with an excellent sensitivity. The CuS@PAD NSs showed a good photothermal conversion efficiency in the near-infrared II (NIR II) region to mediate a good photothermal performance to kill cancer cells. A remarkable antitumor therapeutic effect was achieved in vivo. This work integrated highly sensitive detection to endogenous cancer biomarkers and valid therapeutic potency to tumor-bearing mice, indicating its promising biomedical applications.

Adsorption in Reversed Order of C2 Hydrocarbons on an Ultramicroporous Fluorinated Metal-Organic Framework.

Metal-organic frameworks have been widely studied in the separation of C2 hydrocarbons, which usually preferentially bind unsaturated hydrocarbons with the order of acetylene (C2 H2 )>ethylene (C2 H4 )>ethane (C2 H6 ). Herein, we report an ultramicroporous fluorinated metal-organic framework Zn-FBA (H2 FBA=4,4'-(hexafluoroisopropylidene)bis(benzoic acid)), shows a reversed adsorption order characteristic for C2 hydrocarbons, that the uptake for C2 hydrocarbons of the framework and the binding affinity between the guest molecule and the framework follows the order C2 H6 >C2 H4 >C2 H2 . Density-functional theory calculations confirm that the completely reversed adsorption order behavior is attributed to the close van der Waals interactions and multiple cooperative C-H⋅⋅⋅F hydrogen bonds between the framework and C2 H6 . Moreover, Zn-FBA exhibits a high selectivity of about 2.9 for C2 H6 over C2 H4 at 298 K and 1 bar. The experimental breakthrough studies show that the high-purity C2 H4 can be obtained from C2 H6 and C2 H4 mixtures in one step.

Facile Fabrication of a Foamed Ag3CuS2 Film as an Efficient Self-Supporting Electrocatalyst for Ammonia Electrolysis Producing Hydrogen.

Ammonia (NH3) is one of the hydrogen carriers that has received extensive attention due to its high hydrogen content and carbon-free nature. The ammonia electro-oxidation reaction (AOR) and the liquid AOR (LAOR) are integral parts of an ammonia-based energy system. The exploration of low-cost and efficient electrocatalysts for the AOR and LAOR is very important but very difficult. In this work, a novel self-supporting AOR and LAOR bifunctional electrocatalyst of a Ag3CuS2 film is synthesized by a simple hydrothermal method. The Ag3CuS2 film without a substrate shows efficient catalytic activity and enhanced stability for NH3 electrolysis in both aqueous ammonia solution and liquid ammonia, including an onset potential of 0.7 V for the AOR and an onset potential of 0.4 V for the LAOR. The density functional theory calculations prove that compared to Cu atoms, Ag atoms with appropriate charge density on the surface of Ag3CuS2 are more electrocatalytically active for NH3 splitting, including the low energy barrier in the rate-determining *NH3 dehydrogenation step and the spontaneous tendency in the N2 desorption process. Overall, the foamed Ag3CuS2 film is one of prospective low-cost and stable electrocatalysts for the AOR and LAOR, and the self-supporting strategy without a substrate provides more perspectives to tailor more meaningful and powerful electrocatalysts.

Effects of Pellet Basicity on the Simulated Deposit Formation in Coal-Fired Rotary Kilns for Iron Ore Pellet Production.

Deposit formation in the coal-fired rotary kiln is frequently found in the production of fluxed iron ore pellets by the grate-kiln process and affects normal production. In this paper, the effects of pellet basicity (CaO/SiO2 mass ratio) on the simulated deposit formation were investigated. The results show that the porosity of deposits samples increases from 30.8 to 41.5% as the pellet basicity increases from 0.6 to 1.2, and most of the holes are irregular in shape. The contents of CaO and Fe2O3 in the silicates of the deposit samples increased with increasing basicity. The primary phase of the deposit samples changed from the M2O3 phase region to the clinopyroxene phase region with a lower melting point. As the basicity increased, the calculated proportions of the liquid phases in the deposit samples had an increasing trend. Moreover, the deposit sample adhesion to the refractory brick increases with the increase in pellet basicity.

Rapid detection of miRNA via development of consecutive adenines (polyA)-based electrochemical biosensors.

Herein, we report rapid electrochemical detection of miRNA let-7a based on a DNA probe consisting of a polyA and Fc-co-labeled harpin structure (the polyA-H probe). The polyA-H probe could be facilely immobilized on Au surfaces through the interactions between polyA and Au, followed by its pre-hybridization with a single strand (S1). The probe's surface density could be optimized for minimizing steric hindrance via changing the polyA block length. The target let-7a could be rapidly amplified via loop-mediated isothermal amplification (LAMP) with four simplified primers, followed by inducing the formation of dimeric i-motif (DIM) structure via H+-induced rapid folding of two C-rich sequences of motif strand 1 and strand 2. It was found that, after introducing the as-formed DIM to hybridize the S1, the immobilized polyA20-H probe could rapidly revert to its hairpin structure, sending out a turn-on electrochemical signal of the Fc. The total time for detecting the let-7a was around 80 min, obviously less than that of most of electrochemical DNA sensors reported previously. The biosensor showed a linear relationship of the current response to the let-7a in the range of 10 fM to 50 nM with a limit of detection (LOD) of 5.1 fM. Our biosensors were further tested using human serum spiked with the let-7a and the extracts of the breast adenocarcinoma cells spiked with and without the let-7a, respectively. Satisfied results were obtained. This study shows a potential promising future of development of electrochemical biosensors for rapid detection of miRNAs in the application of clinical practice.