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Incidental ingestion of household dust is an important arsenic (As) exposure pathway for children. However, compared to soils, assessment of As relative bioavailability (RBA) in household dust is limited. In this study, As-RBA in 12 household dust samples (7-38 mg kg-1) was measured using an in vivo mouse model and compared to As bioaccessibility determined using 4 assays Solubility Bioaccessibility Research Consortium method (SBRC), in vitro gastrointestinal method (IVG), Deutsches Institut fur Normunge.V. method (DIN), and physiologically based extraction test (PBET)]. Arsenic RBA ranged from 21.8 ± 1.6 to 85.6 ± 7.2% with samples containing low Fe and high total organic carbon content having higher As-RBA. Strong in vivo-in vitro correlations (IVIVC) were found between As-RBA and As bioaccessibility for SBRC and DIN (r2 = 0.63-0.85), but weaker ones were obtained for IVG and PBET (r2 = 0.29-0.55). The developed IVIVC for SBRC and DIN were used to calculate As-RBA based on As bioaccessibility for an additional 12 household dust samples. Although As bioaccessibility differed significantly (up to 7.7-fold) based on in vitro methods, predicted As-RBA was less variable (up to 3.0-fold) when calculated using As bioaccessibility data and the corresponding IVTVC. Our data suggested that both SBRC and DIN had potential to assess As bioavailability in household dust samples; however, additional research is needed. [ABSTRACT FROM AUTHOR]

House dust samples containing 25-738 mg of Pb kg-1 from 15 cities in China were assessed for in vitro Pb bio-accessibility and in vivo Pb relative bioavailability. On the basis of stable Pb isotope ratios, the Pb in dust samples mainly originated from coal combustion. Lead bio-accessibility was determined using gastric (GP) and intestinal phase (IP) of solubility bioaccessibility research consortium (SBRC), in vitro gastrointestinal (IVG), Deutsches Institut für Normunge.V. (DIN), and physiologically based extraction test methods (PBET), while Pb relative bioavailability (RBA) was determined using a mouse blood model. Lead bioaccessibility in 24 house dust samples varied significantly (23-99%) depending on the methods. Values from the IP were considerably lower than those from the GP because of the co-precipitation of Pb with iron and readsorption onto the dust matrix. The SBRC assay with lower GP pH produced higher Pb bioaccessibility because of enhanced Pb dissolution. When compared to mouse blood data using 12 dust samples (29-60%), SBRC- GP and DIN-GP data were correlated with Pb RBA with r2 values of 0.68 and 0.85 and intercepts 3.15 and 17.4, respectively. Overall, SBRC-GP had potential to predict Pb RBA in dust samples. However, our data suggested that more research is needed to develop a valid in vitro method for predicting Pb RBA in house dust. [ABSTRACT FROM AUTHOR]

Our previous experiment confirmed that high-mobility group box chromosomal protein 1 (HMGB1) was involved in the pathogenesis of Lupus nephritis (LN) by upregulating the proliferation of the mouse mesangial cell line (MMC) through the cyclin D1/CDK4/p16 system, but the precise mechanism is still unknown. Therefore, in the present study, we demonstrated that HMGB1 induced the proliferation of MMC cells in a time- and concentration-dependent manner, downregulated phosphatase and tensin homolog deleted on chromosome ten (PTEN) expression, increased the level of Akt serine 473 phosphorylation, and induced p65 subunit nuclear translocation. The overexpression of PTEN prevented the upregulation of HMGB1-induced proliferation by blocking the activation of Akt. The knockdown of Akt by siRNA technology and blocking the nuclear factor-κ (NF-κ) pathway using pyrrolidine dithiocarbamate (PDTC) and SN50, inhibitors of NF-κ, both attenuated the HMGB1-induced proliferation by counteracting the activation of the cyclin D1. In addition, while sh-Akt partly blocked the nuclear translocation of the p65 subunit, PDTC did not affect the activation of the Akt induced by HMGB1 in MMC cells. These findings indicate that HMGB1 induced the proliferation of MMC cells by activating the PTEN/phosphoinositide-3-kinase (PI3K)/Akt/NF-κ signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Microbubbles (MBs) can serve as an ultrasound contrast agent, and has the potential for magnetic resonance imaging (MRI). Due to the relatively low effect of MBs on MRI, it is necessary to develop new MBs that are more suitable for MRI. In this study, we evaluate the properties of SonoVue® and custom-made Fe3O4-nanoparticle-embedded microbubbles (Fe3O4-MBs) in terms of contrast agents for ultrsonography (US) and MRI. Methodology/Principal Findings: A total of 20 HepG2 subcutaneous-tumor-bearing nude mice were randomly assigned to 2 groups (i.e., n = 10 mice each group), one for US test and the other for MRI test. Within each group, two tests were performed for each mouse. The contrast agent for the first test is SonoVue®, and the second is Fe3O4-MBs. US was performed using a TechnosMPX US system (Esaote, Italy) with a contrast-tuned imaging (CnTITM) mode. MRI was performed using a 7.0T Micro-MRI (PharmaScan, Bruker Biospin GmbH, Germany) with an EPI-T2 sequence. The data of signal-to-noise ratio (SNR) from the region-of-interest of each US and MR image was calculated by ImageJ (National Institute of Health, USA). In group 1, enhancement of SonoVue® was significantly higher than Fe3O4-MBs on US (P,0.001). In group 2, negative enhancement of Fe3O4-MBs was significantly higher than SonoVue® on MRI (P<0.001). The time to peak showed no significant differences between US and MRI, both of which used the same MBs (P>0.05). The SNR analysis of the enhancement process reveals a strong negative correlation in both cases (i.e., SonoVue® r =20.733, Fe3O4-MBs r =20.903, with P<0.05). Conclusions: It might be important to change the Fe3O4-MBs' shell structure and/or the imagining strategy of US to improve the imaging quality of Fe3O4-MBs on US. As an intriguing prospect that can be detected by US and MRI, MBs are worthy of further study. [ABSTRACT FROM AUTHOR]

Background: Accurate prognostication of locally advanced nasopharyngeal carcinoma (NPC) will benefit patients for tailored therapy. Here, we addressed this issue by developing a mathematical algorithm based on support vector machine (SVM) through integrating the expression levels of multi-biomarkers. Methodology/Principal Findings: Ninety-seven locally advanced NPC patients in a randomized controlled trial (RCT), consisting of 48 cases serving as training set and 49 cases as testing set of SVM models, with 5-year follow-up were studied. We designed SVM models by selecting the variables from 38 tissue molecular biomarkers, which represent 6 tumorigenesis signaling pathways, and 3 EBV-related serological biomarkers. We designed 3 SVM models to refine prognosis of NPC with 5-year follow-up. The SVM1 displayed highly predictive sensitivity (sensitivity, specificity were 88.0% and 81.9%, respectively) by integrating the expression of 7 molecular biomarkers. The SVM2 model showed highly predictive specificity (sensitivity, specificity were 84.0% and 94.5%, respectively) by grouping the expression level of 12 molecular biomarkers and 3 EBV-related serological biomarkers. The SVM3 model, constructed by combination SVM1 with SVM2, displayed a high predictive capacity (sensitivity, specificity were 88.0% and 90.3%, respectively). We found that 3 SVM models had strong power in classification of prognosis. Moreover, Cox multivariate regression analysis confirmed these 3 SVM models were all the significant independent prognostic model for overall survival in testing set and overall patients. Conclusions/Significance: Our SVM prognostic models designed in the RCT displayed strong power in refining patient prognosis for locally advanced NPC, potentially directing future target therapy against the related signaling pathways. [ABSTRACT FROM AUTHOR]

New lead zirconate titanate/zinc oxide nanowhisker (PZT/ZnO) ceramics were fabricated by a conventional solid state processing and their structures, piezoelectric, ferroelectric and mechanical properties were studied. Both the PZT perovskite and ZnO phases can be observed from the X-ray diffraction patterns. The grain size of ceramics is reduced due to the ZnO addition. The incorporation of ZnO into the PZT ceramics improves the strength and toughness, while deteriorates the piezoelectric and ferroelectric properties. For the PZT/ZnO ceramics with 1-2 wt% ZnO, the mechanical properties become optimum, meanwhile maintain good piezoelectric and ferroelectric properties: σ = 376-484 MPa, σ = 115-121 MPa, K = 1.41-1.54 MPa m, d = 442-490 pC/N, k = 0.54-0.55, ε = 3,322-3,980, Q = 99-101, tanδ = 1.6%-1.7%, P = 21.5-26.9 μC/cm and E = 8.1-8.6 kV/cm. [ABSTRACT FROM AUTHOR]

The article focuses on the crystal structure of poly[aquahemi [μ4-1,6-bis(1,2,4-triazol-1-yl)hexane](μ2-5-nitroisophthalato)cadmium(II)]. The topologies of metal-organic frameworks (MOFs) can be modified by the coordination geometry of a metal ion and the chemical structure of the selected organic ligand. Organic carboxylate ligands like the 5-nitroisophthalate is used to construct MOFs with different topologies and properties.

The addition of ZnO nanowhiskers (ZnOw) in lead zirconate titanate (PZT) matrices results in reinforced composite materials but deteriorates their electrical properties. In this study, novel piezoelectric PZT/ZnOw composites modified with Nb2O5 were successfully fabricated using solid-state sintering method. The experimental results showed that the addition of 0.5 wt% Nb2O5 resulted in highly dense and homogenous PZT composites after sintering at 1150°C, with good piezoelectric and ferroelectric properties similar to pure PZT, specifically piezoelectric constant d33=665 pC/N, electromechanical coupling factor kp=0.7, relative dielectric constant ϵ=5048, and remnant polarization Pr=30.2 μC/cm°. The ''soft effect'' of Nb5+ ions, reflected in the improvement of the aforementioned properties, is attributed to the accommodation of Nb51 ions at the B sites of the lattice of PZT. Compared with the PZT/ZnOw reinforced composites, the mechanical properties were slightly improved by adding 0.5 wt% Nb2O5, where flexural strength σf of 128 MPa and fracture toughness KIC of 1.46 MPa · m½ were measured. [ABSTRACT FROM AUTHOR]

The poly(bromothymol blue) film was prepared using a simple cyclic voltammetry method. Field emission scanning electron microscopy and electrochemical methods were employed to characterize this film. When the film was electropolymerized on an electrode, it showed excellent catalytic activity toward the oxidation of dopamine (DA) in pH 4.0 phosphate buffer solution. In addition, the overlapped voltammetric responses of dopamine and ascorbic acid were resolved into two well-defined peaks by the film-modified electrode with a large peak separation of 0.17 V. A calibration curve for DA was obtained by the amperometric method in the range of 3.0-195.0 μM with a correlation coefficient of 0.9997. The film-modified electrode has been successfully used to measure the concentration of DA in injections and human serum samples. [ABSTRACT FROM AUTHOR]

A series of novel hydroxamic acid complexes (ML [ABSTRACT FROM AUTHOR]

Abstract A hydroxamic acid (HL) containing benzo-15-crown-5 and their copper(II), zinc(II), cobalt(II) and manganese(II) complexes have been synthesized and studied as catalysts for the cleavage of bis(4-nitrophenyl)phosphate (BNPP). The catalytic properties of these complexes and the kinetics and mechanism of BNPP hydrolysis have been investigated. The kinetic mathematical model of BNPP cleavage catalyzed by these complexes has been proposed. The effects of reaction temperature and metal ion in the complexes on the rate of BNPP catalytic hydrolysis have been discussed. The results show that the hydroxamic acid complexes containing benzo-15-crown-5 exhibit high activity in the BNPP catalyzed hydrolysis; the pseudo-first-order-rate constants of BNPP hydrolysis catalyzed by the complexes increase along with the increases of pH of the buffer solution from 7.50 to 9.50; the activity of different metal ions decreases in the order: Co2+ > Cu2+ > Zn2+ > Mn2+; the pseudo-first-order-rate constants of BNPP hydrolysis catalyzed by the complexes is 2.24 105 ~ 3.24 105 times as large as that of spontaneous hydrolysis of BNPP. [ABSTRACT FROM AUTHOR]

Economical and efficient long-distance oil and natural gas pipe transportation technologies are greatly demanded. Nowadays, oil and gas mixed transportation is gradually put into practice and researchers pay much attention on the theories of two-phase flow in pipe. Methods that can efficiently solve problems of this field are being put forward including hydraulic approach. A new approach, the Rotatable Coordinate Axis, is proposed in this paper. It is used to study the hydraulic characters of two-phase stratified flow in pipe. Based on the new method, the plane flow model for stratified turbulent flow in pipe is built. Then, we can obtain the analytic formulas of velocity, discharge etc. in wells and pipes by this model. To prove the theory of the plane flow model, experiments of aeration in stratified pipe is conducted with the aeration experiment device. The experiment data showed that aeration could effectively achieve the resistance reduction in pipeline, which can offer great theory support to the development of oil and natural gas mixed transportation technology. [Copyright &y& Elsevier]

Abstract Polyether-bridged dihydroxamic acids and their mono- and binuclear copper(II), and cobalt(II) complexes have been synthesized and employed as models to mimic hydrolase in the catalytic hydrolysis of p-nitrophenyl picolinate (PNPP). The kinetics and the mechanism of PNPP hydrolysis have been investigated. The kinetic mathematical model of PNPP cleavage by the complexes has been proposed. The effects of the different central metal ion, mono- and binuclear metal, the pseudo-macrocyclic polyether constructed by the polyethoxy group in complexes, and reactive temperature on the rate of PNPP catalytic hydrolysis have been examined. The results show that the transition-metal dihydroxamates exhibit high catalytic activity in the PNPP hydrolysis; the rate of the PNPP hydrolysis increases with the increase in pH of the buffer solution; the catalytic activity of binuclear complexes is higher than that of mononuclear complexes; the catalytic activity of copper(II) complex is about four times that of the cobalt(II) complex; the pseudo-macrocyclic polyether can synergetically activate H2O coordinated to the metal ion with the central metal ion together and promote the PNPP catalytic hydrolysis. [ABSTRACT FROM AUTHOR]

Background: Mesenchymal stem cells (MSCs) are considered a promising therapeutic strategy for rheumatoid arthritis (RA), but the current clinical results are varied. This study is to analyze the therapeutic effect of cell-based strategies on RA. Materials and Methods: The searches were performed with public databases from inception to June 17, 2021. Randomized controlled trials researching cell-based therapies in RA patients were included. Results: Eight studies, including 480 patients, were included in the analysis. The results showed that compared to the control, MSC treatment significantly reduced the disease activity score (DAS) at the second standardized mean difference (SMD): -0.70; 95% confidence interval (CI): -1.25, -0.15; P = 0.01) and 3rd month (SMD: -1.47; 95% CI: -2.77, -0.18; P < 0.01) and significantly reduced the rheumatoid factor (RF) level at the first (SMD: -0.38; 95% CI: -0.72, -0.05; P = 0.03) and 6th months (SMD: -0.81; 95% CI: -1.32, -0.31; P < 0.01). In the network meta-analysis, MSCs combined with interferon-γ (MSC_IFN) had a significant effect on increasing the American college of rheumatology criteria (ACR) 20, ACR50, and DAS <3.2 populations, had a significant effect on reducing the DAS, and decreased the RF level for a long period. Conclusion: MSCs could relieve the DAS of RA patients in the short term and reduce the level of RF. MSC_IFN showed a more obvious effect, which could significantly improve the results of ACR20, ACR50, and DAS <3.2 and reduce the DAS and RF levels. [ABSTRACT FROM AUTHOR]

Summary: Background: Osteosarcoma (OS) is the most common primary malignant bone tumor in adolescents. The molecular mechanism behind OS progression and metastasis remains poorly understood, which limits the effectiveness of current therapies. RNA N6-methyladenosine (m6A) modification plays a critical role in influencing RNA fate. However, the biological significance of m6A modification and its potential regulatory mechanisms in the development of OS remain unclear. Methods: Liquid chromatography-tandem mass spectrometry (LC-MS/MS), dot blotting, and colorimetric ELISA were used to detect m6A levels. Western blotting, quantitative real-time PCR (RT-qPCR) and immunohistochemistry (IHC) were used to investigate METTL14 expression levels. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and transcriptomic RNA sequencing (RNA-seq) were used to screen the target genes of METTL14. RNA pull-down and RNA immunoprecipitation (RIP) assays were conducted to explore the specific binding of target genes and relevant m6A “readers”. RNA stability and polysome analysis assays were used to detect the half-lives and translation efficiencies of the downstream genes of METTL14. IHC and clinical data were applied to explore the clinical correlations of METTL14 and its downstream target genes with the prognosis of OS. Findings: We observed the abundance of m6A modifications in OS and revealed that METTL14 plays an oncogenic role in facilitating OS progression. MeRIP-seq and RNA-seq revealed that MN1 is a downstream gene of METTL14. MN1 contributes to tumor progression and all-trans-retinoic acid (ATRA) chemotherapy resistance in OS. Mechanistically, MN1 is methylated by METTL14, specifically in the coding sequence (CDS) regions, and this modification is recognized by the specific m6A reader insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) to prevent MN1 mRNA degradation and promote it translation efficiency. IHC showed that MN1 expression was positively correlated with METTL14 and IGF2BP2 expression in OS tissues. The METTL14-IGF2BP2-MN1 panel demonstrated more promising prognostic value for OS patients than any of these molecules individually. Interpretation: Our study revealed that METTL14 contributes to OS progression and ATRA resistance as an m6A RNA methylase by regulating the stability and translation efficiency of MN1 and thus provides both an underlying biomarker panel for prognosis prediction in OS patients. Funding: This work was supported by the National Natural Science Foundation of China (Grants 81972510 and 81772864).

Xinjiang brown cattle have better meat quality than Kazakh cattle. Circular RNAs (circRNAs) are a type of RNA that can participate in the regulation of gene transcription. Whether circRNAs are differentially expressed in the longissimus dorsi between these two types of cattle and whether differentially expressed circRNAs regulate muscle formation and differentiation are still unknown. In this study, we established two RNA-seq libraries, each of which consisted of three samples. A total of 5,177 circRNAs were identified in longissimus dorsi samples from Kazakh cattle and Xinjiang brown cattle using the Illumina platform, 46 of which were differentially expressed. Fifty-five Gene Ontology terms were significantly enriched, and 12 Kyoto Encyclopedia of Genes and Genomes pathways were identified for the differentially expressed genes. Muscle biological processes were associated with the origin genes of the differentially expressed circRNAs. In addition, we randomly selected six overexpressed circRNAs and compared their levels in longissimus dorsi tissue from Kazakh cattle and Xinjiang brown cattle using RT-qPCR. Furthermore, we predicted 66 interactions among 65 circRNAs and 14 miRNAs using miRanda and established a coexpression network. A few microRNAs known for their involvement in myoblast regulation, such as miR-133b and miR-664a, were identified in this network. Notably, bta_circ_03789_1 and bta_circ_05453_1 are potential miRNA sponges that may regulate insulin-like growth factor 1 receptor expression. These findings provide an important reference for prospective investigations of the role of circRNA in longissimus muscle growth and development. This study provides a theoretical basis for targeting circRNAs to improve beef quality and taste.

In this paper, an efficient algorithm is developed to automatically detect and extract coronal loops. First of all, in the algorithm, three characteristics associated with coronal loops are used to construct a match filter able to enhance the loops. Secondly, the method combining a high-pass filter (unsharp-mask enhancement) with a global threshold is used to further enhance and segment the loops. Thirdly, to extract every individual coronal loop and obtain their parameters (the 2D projected space coordinates and lengths) from the segmented loops, a clustering method of the pixels with approximate local direction and connected domain is further used. Fourthly, to evaluate the performance of the developed algorithm, images observed by the Transition Region and Coronal Explorer (TRACE), the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO) and the High-Resolution Coronal Imager (Hi-C) are used, and comparison experiments between the existing algorithms and the developed algorithm are performed. Finally, it is found that the developed algorithm is commensurate with the two most promising algorithms, oriented coronal curved loop tracing (OCCULT) and its improved version, OCCULT-2, in performance. Therefore, for scientific applications associated with coronal loops, the developed algorithm will be a powerful tool. [ABSTRACT FROM AUTHOR]