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The incorporation of nuclear quadrupole interaction into electron spin-echo modulation spectra by second-order perturbation methods has been developed for both two-pulse and three-pulse echo sequences. The results have been compared with exact numerical diagonalization of the Hamiltonian and with a first-order perturbation treatment. Model calculations have been carried out for deuterium (I=1) and aluminum (I=5/2) nuclei. It is shown that the second-order expressions can be used to obtain relatively accurate values for the number and distance of interacting nuclei at electron–nuclear distances greater than 0.26 nm. The procedure is more limited when the quadrupolar interaction exceeds the dipolar interaction when neither can be neglected. [ABSTRACT FROM AUTHOR]

Fibrates, which are agonists of peroxisome proliferator-activated receptor alpha, have received increasing attention in the treatment of primary biliary cholangitis. Reduced alkaline phosphatase levels and improved clinical outcomes were observed in patients with primary biliary cholangitis with an inadequate response to ursodeoxycholic acid (UDCA) monotherapy4 when treated with bezafibrate or fenofibrate combined with UDCA. In contrast to obeticholic acid, which exacerbates pruritus in patients, fibrates have been shown to relieve pruritus. Clinical trial outcomes show potential for the treatment of primary biliary cholangitis by targeting peroxisome proliferator-activated receptors. It is currently agreed that primary biliary cholangitis is an autoimmune-mediated cholestatic liver disease, and peroxisome proliferator-activated receptor is a nuclear receptor that regulates the functions of multiple immune cells, thus playing an important role in regulating innate and adaptive immunity. Therefore, this review focuses on the immune disorder of primary biliary cholangitis and summarizes the regulation of hepatic immunity when peroxisome proliferator-activated receptors are targeted for treating primary biliary cholangitis.

Liver fibrosis (LF) is a major disease that threatens human health. Hepatic stellate cells (HSCs) contribute directly to LF via extracellular matrix (ECM) secretion. Moreover, RXRα is an important nuclear receptor that plays a key regulatory role in HSC activation. Meanwhile, microRNAs (miRNAs) have been identified as significant regulators of LF development. In particular, miR-654-5p is involved in cellular migration and proliferation, and via bioinformatics analysis, has been identified as a potential factor that targets RXRα in humans and in mice. However, the precise relationship between miR-654-5p and RXRα in the context of LF, remains unknown and is the primary focus of the current study. To establish in vitro activated cell model human primary HSCs were cultured in vitro and LX-2 cells were stimulated with recombinant human TGF-β1. mRNA and protein levels of RXRα, miR-654-5p and fibrogenic genes were compared in quiescent and activated HSCs. Moreover, after transfected with miR-654-5p mimics, the expression changes of above related genes in LX-2 cells were estimated. Meanwhile, cell proliferation and apoptosis were detected in miR-654-5p overexpressed LX-2 cells. Simultaneously, the targeted binding between miR-654-5p and RXRα was verified in LX-2 cells. Carbon tetrachloride (CCl4)-induced mouse model with liver fibrosis was use to research the role of the miR-654-5p in vitro. Our results show that miR-654-5p expression levels increased in activated human HSCs and TGFβ-treated LX-2 cells. Moreover, miR-654-5p mimics markedly promoted LX-2 cell proliferation while inhibiting their apoptosis. Accordingly, the expression levels of RXRα are decreased in activated HSCs and LX-2 cells. Additionally, dual-luciferase reporter assay results reveal direct targeting of RXRα by miR-654-5p. Similarly, in vivo miR-654-5p overexpression aggravates LF in mice that are intraperitoneally injected with CCl4. Taken together, our findings elucidated a novel molecular mechanism with potential use for treatment of LF.

Abstract Background Hepatitis C virus (HCV) infection is a public health issue for which an effective universal screening method is urgently needed. An oral anti-HCV test could provide a noninvasive and rapid screening strategy for HCV infection. This study evaluated the performance of a new point-of-care oral assay developed by Well for the detection of HCV antibody. Methods Individuals from three centers with and without HCV infection were enrolled. All participants were tested for oral HCV antibody using the Well assay and for serum HCV antibody using established tests (ARCHITECT i2000 anti-HCV assay and InTec serum anti-HCV assay). For participants who obtained positive results, HCV RNA was tested for verification. Some patients underwent the OraQuick HCV test at the same time, and some self-tested with the Well assay during the same period. Results A total of 1179 participants, including 486 patients with chronic HCV infection, 108 patients with other liver diseases, and 585 individuals who underwent physical examination, were enrolled. The Well anti-HCV test had a sensitivity of 91.88% (95% confidence interval [CI]: 88.97–94.09%) and a specificity of 98.00% (96.58–98.86%) for oral HCV antibody detection. The consistency between the Well and InTec assays was 97.02% (1138/1179). The consistency between the Well and OraQuick assays was 98.50% (197/200). Furthermore, the results of self-testing were highly consistent with those of researcher-administered tests (Kappa = 0.979). In addition, the HCV RNA results also showed that HCV RNA could only be detected on 1 of the 39 false-negative samples, and for 172 positive HCV RNA results, 171 could be detected by the Well oral anti-HCV assay. Conclusions The Well oral anti-HCV test offers high sensitivity and specificity and performed comparably to both the OraQuick assay and InTec assay for HCV diagnosis. Thus, the Well test represents a new tool for universal HCV screening to identify infected patients, particularly in regions with limited medical resources.

MicroRNAs (miRNAs) participate in hepatic stellate cell (HSC) activation, which drives liver fibrosis initiation and progression. We aimed to identify novel hepatic fibrosis targets using miRNA sequencing (miRNA-seq) of human primary HSCs. Surgically resected liver tissues were used to extract HSCs. Based on next-generation sequencing, miRNA-seq was performed on four pairs of HSCs before and after in vitro culture. Additionally, we compared our data with open access miRNA-seq data derived from fourteen cirrhotic and nine healthy liver tissues. Selected miRNAs associated with fibrosis were verified by quantitative real-time PCR. Target mRNAs of differentially expressed (DE) miRNAs were predicted to construct co-expression networks. We identified 230 DEmiRNAs (118 upregulated and 112 downregulated) upon HSC activation. Of the 17 miRNAs with the most significant differences in expression, liver disease-related miRNAs included miR-758-3p, miR-493-5p, miR-409-3p, miR-31-5p, miR-1268a, and miR-381-3p, which might play roles in hepatic fibrosis. Moreover, let-7g-5p, miR-107, miR-122-5p, miR-127-3p, miR-139-5p, miR-148a-3p, miR-194-5p, miR-215-5p, miR-26a-5p, miR-340-5p, miR-451a, and miR-99a-5p were common between our data and the publicly available sequencing data. A co-expression network comprising 1891 matched miRNA–mRNA pairs representing 138 DEmiRNAs and 1414 DEmRNAs was constructed. MiR-1268a and miR-665, possessing the richest target DEmRNAs, may be vital in HSC activation. The targeted genes were involved in collagen metabolism, extracellular matrix structural constituent, cytoskeletal protein binding, and cell adhesion. The miRNAs we identified may provide a basis and reference for the selection of diagnostic and therapeutic targets for hepatic fibrosis.

Aiming at the problems that the conventional permanent magnet synchronous motor direct torque control system (PMSM-DTC) is susceptible to the influence of parameter change and torque ripple, it is proposed that the space voltage vector modulation technique (SVPWM) is used instead of the traditional sinusoidal pulse width modulation (SPWM), on the basis of which the second-order sliding mode variable structure control rate with super-twising algorithm is introduced, with the stator flux linkage and torque as the controlled object to design the controller instead of traditional PI controller in the system. The simulation results show that the strategy not only eliminates effectively the first-order sliding mode chattering problems, significantly reducing the stator flux linkage and torque ripple, but also has strong ability of speed tracking, with robustness to load disturbance, and parameter changes, etc., therefore can be well applied in motor control.

The traditional mechanical encoder has been used to detect the position and speed of rotors in permanent magnet synchronous motor control system, which has the problems of high cost, low system reliability, being susceptible to interference and difficult to apply in a complex environment. A novel speed estimation method based on sliding mode adaptive system is proposed in this paper, which improves the speed estimation accuracy and system robustness to achieve motor speed sensorless control. The simulation results indicate that the control strategy could avoid the limitations of traditional mechanical encoders, and estimate the rotor speed and position angle accurately when suddenly applied load.

Background/Aims: The present study aims to explore the protective role and mechanism of ginsenoside Rg1 combined with bone marrow mesenchymal stem cell (BMSC) transplantation for cerebral ischemia reperfusion injury (CIRI) in rat brain. Methods: One hundred twenty male SD rats were randomly divided into a sham group, an Ischemia Reperfusion (IR) group, an IR group treated with BMSC transplantation (IR+BMSCs), an IR group treated with Rg1 (IR+Rg1), and an IR group treated with BMSC transplantation and Rg1 (IR+Rg1+BMSCs). To establish a CIRI model, right middle cerebral artery embolization was used. The neurological score, 2,3,5-triphenyltet-razolium chloride monohydrate (TTC) staining and brain water content were detected to assess the treatment efficiency. HE staining and TUNEL were used to explore the pathologic changes and apoptosis. To explore the protein levels of neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP), immunofluoresence was utilized. Western blotting was used to explore apoptosis-related proteins such as Bcl-2 and Bax. Results: Compared with the sham group, the IR group demonstrated obvious ischemic changes, such as significant neurologic defects and enhanced brain water content. The Rg1 treatment resulted in an obvious decrease in cell apoptosis and improved ischemic conditions. By BMSC transplantation, the transplanted cells could be differentiated into neurons and glial cells, which also improved cerebral ischemia. More importantly, the IR+Rg1+BMSCs group showed the best treatment efficiency with reduced cell apoptosis and better cerebral recovery. Conclusions: The Rg1 treatment resulted in an obvious decrease in cell apoptosis, while the transplanted cells could be differentiated into neurons and glial cells, which also improved cerebral ischemia.

Glycerine is a by-product of the biodiesel industry. Owing to the exponential growth of biodiesel production worldwide and particularly in Europe, the glycerine market has been driven during the last few years by the oversupply being generated by the biodiesel industry. Prices of both refined and crude glycerine have fallen to all-time lows. Consequently, there are clear signs that demand for glycerine is growing strongly with new usages both for crude and refined glycerine now to the fore. This article attempts to analyse to what extent a « substitution/new-usage breakthrough » for glycerine is occurring and will propose a supply/demand scenario for the coming 3 years. It will also attempt to predict how glycerine prices will develop over the same period.