Search

Abstract The HBV core protein (HBc) is an important viral protein of HBV that plays an indispensable role in the lifecycle of HBV, including capsid assembly and transport, reverse transcription and virus release. In recent years, evidence has shown that HBc may be involved in the malignant progression of HCC. Thus, HBc is an attractive target for antiviral agents and provides a new strategy for the treatment of HBV-related HCC. Here, we identified a novel anti‐HBc compound—colchicine, an alkaloid compound—that promoted selective autophagic degradation of HBc through the AMPK/mTOR/ULK1 signalling pathway. We further confirmed that colchicine promoted the selective autophagy of HBc by enhancing the binding of HBc to the autophagy receptor p62. Finally, we evaluated the effects of colchicine on HBV replication and HBc-mediated HCC metastasis in vitro and in vivo. Our research indicated that the inhibitory effects of colchicine on HBV and HBV-related HCC depend on the selective autophagic degradation of HBc. Thus, colchicine is not only a promising therapeutic strategy for chronic hepatitis B but also a new treatment for HBV-related HCC.

Abstract Background Progressive hepatitis B virus (HBV) infection can result in cirrhosis, hepatocellular cancer, and chronic hepatitis. While antiviral drugs that are now on the market are efficient in controlling HBV infection, finding a functional cure is still quite difficult. Identifying host factors involved in regulating the HBV life cycle will contribute to the development of new antiviral strategies. Zinc finger proteins have a significant function in HBV replication, according to earlier studies. Zinc finger protein 148 (ZNF148), a zinc finger transcription factor, regulates the expression of various genes by specifically binding to GC-rich sequences within promoter regions. The function of ZNF148 in HBV replication was investigated in this study. Methods HepG2-Na+/taurocholate cotransporting polypeptide (HepG2-NTCP) cells and Huh7 cells were used to evaluate the function of ZNF148 in vitro. Northern blotting and real-time PCR were used to quantify the amount of viral RNA. Southern blotting and real-time PCR were used to quantify the amount of viral DNA. Viral protein levels were elevated, according to the Western blot results. Dual-luciferase reporter assays were used to examine the transcriptional activity of viral promoters. ZNF148’s impact on HBV in vivo was investigated using an established rcccDNA mouse model. Results ZNF148 overexpression significantly decreased the levels of HBV RNAs and HBV core DNA in HBV-infected HepG2-NTCP cells and Huh7 cells expressing prcccDNA. Silencing ZNF148 exhibited the opposite effects in both cell lines. Furthermore, ZNF148 inhibited the activity of HBV ENII/Cp and the transcriptional activity of cccDNA. Mechanistic studies revealed that ZNF148 attenuated retinoid X receptor alpha (RXRα) expression by binding to the RXRα promoter sequence. RXRα binding site mutation or RXRα overexpression abolished the suppressive effect of ZNF148 on HBV replication. The inhibitory effect of ZNF148 was also observed in the rcccDNA mouse model. Conclusions ZNF148 inhibited HBV replication by downregulating RXRα transcription. Our findings reveal that ZNF148 may be a new target for anti-HBV strategies.

Abstract Persistent transcription of HBV covalently closed circular DNA (cccDNA) is critical for chronic HBV infection. Silencing cccDNA transcription through epigenetic mechanisms offers an effective strategy to control HBV. Long non‐coding RNAs (lncRNAs), as important epigenetic regulators, have an unclear role in cccDNA transcription regulation. In this study, lncRNA sequencing (lncRNA seq) is conducted on five pairs of HBV‐positive and HBV‐negative liver tissue. Through analysis, HOXA‐AS2 (HOXA cluster antisense RNA 2) is identified as a significantly upregulated lncRNA in HBV‐infected livers. Further experiments demonstrate that HBV DNA polymerase (DNA pol) induces HOXA‐AS2 after establishing persistent high‐level HBV replication. Functional studies reveal that HOXA‐AS2 physically binds to cccDNA and significantly inhibits its transcription. Mechanistically, HOXA‐AS2 recruits the MTA1‐HDAC1/2 deacetylase complex to cccDNA minichromosome by physically interacting with metastasis associated 1 (MTA1) subunit, resulting in reduced acetylation of histone H3 at lysine 9 (H3K9ac) and lysine 27 (H3K27ac) associated with cccDNA and subsequently suppressing cccDNA transcription. Altogether, the study reveals a mechanism to self‐limit HBV replication, wherein the upregulation of lncRNA HOXA‐AS2, induced by HBV DNA pol, can epigenetically suppress cccDNA transcription.

Background & Aims: Current antiviral drugs, including nucleoside analogs and interferon, fail to eliminate the HBV covalently closed circular DNA (cccDNA), which serves as a transcript template in infected hepatocytes. Silencing the HBV X protein, which plays a crucial role in cccDNA transcription, is a promising approach to inhibit HBV replication. Therefore, the identification of novel compounds that can inhibit HBx-mediated cccDNA transcription is critical. Methods: Initially, a compound library consisting of 715 monomers derived from traditional Chinese medicines known for their liver-protecting properties was established. Then, MTT assays were used to determine the cytotoxicity of each compound. The effect of candidates on Flag-HBx expression was examined by real-time PCR and western blotting in Flag-HBx transfected HepG2-NTCP cells. Ultimately, the antiviral effect of gambogic acid (GA) on HBV was observed in HBV-infected HepG2-NTCP cells. Mechanistically, the functional role of DTX1 in GA-induced HBV inhibition was examined using RNA-seq. Finally, the antiviral effect of GA was estimated in vivo. Results: Gambogic acid (GA), a natural bioactive compound with a myriad of biological activities, markedly reduced Flag-HBx expression. Potent and dose-dependent reductions in extracellular HBV RNAs, HBV DNA, HBsAg, HBeAg and HBc protein were discovered three days after GA treatment in HBV-infected cells, accompanied by the absence of significant cytotoxicity. Furthermore, our research revealed that GA exhibited a dose-dependent inhibition of HBx expression, which is a pleiotropic protein required for HBV infection in vivo. We explored the mechanisms underlying GA-mediated inhibition of HBV and confirmed that this inhibition is accomplished by upregulating the expression of the DTX1 gene and boosting the Notch signaling pathway. Finally, the inhibitory effect of GA on HBV replication was tested in vivo using a mouse model of hepatitis B virus recombinant cccDNA. Conclusions: Herein, we discovered GA, which is a natural bioactive compound that targets HBx to inhibit hepatitis B virus replication by activating the DTX1-Notch signaling pathway.

To address the problem of insufficient real-world data on planetary gearboxes, which makes it difficult to diagnose faults using deep learning methods, it is possible to obtain sufficient simulation fault data through dynamic simulation models and then reduce the difference between simulation data and real data using transfer learning methods, thereby applying diagnostic knowledge from simulation data to real planetary gearboxes. However, the label space of real data may be a subset of the label space of simulation data. In this case, existing transfer learning methods are susceptible to interference from outlier label spaces in simulation data, resulting in mismatching. To address this issue, this paper introduces multiple domain classifiers and a weighted learning scheme on the basis of existing domain adversarial transfer learning methods to evaluate the transferability of simulation data and adaptively measure their contribution to label predictor and domain classifiers, filter the interference of unrelated categories of simulation data, and achieve accurate matching of real data. Finally, partial transfer experiments are conducted to verify the effectiveness of the proposed method, and the experimental results show that the diagnostic accuracy of this method is higher than existing transfer learning methods.

To study the influence of the geometric structure of the probe coil on the electromagnetic characteristics of the eddy current probe in the process of eddy current testing, based on the principle of eddy current testing, different probe coil models were established using finite element software. These geometric structure parameters include the difference between the inner and outer radius, thickness, and equivalent radius. The magnetic field distribution around the probe is simulated and analyzed under different parameters, and the detection performance of the probe is judged in combination with the change rate of the magnetic field around the probe coil. The simulation results show that at a closer position, increasing the difference between the inner and outer radii, reducing the thickness, and reducing the equivalent radius are beneficial to improve the resolution of the probe coil. At a far position, reducing the difference between the inner and outer radii, increasing the thickness, and reducing the equivalent radius are beneficial to improve the resolution of the probe coil. At the same time, the accuracy of the simulation data is verified by comparing the theoretical values with the simulated values under different conditions. Therefore, the obtained conclusions can provide a reference and basis for the optimal design of the probe structure.

Aiming at the problem of excessive noise in the gearbox of a certain sweeper， a gearbox dynamics model is established in the multi-body dynamics software RecurDyn， the dynamic meshing force of the gear pair under steady-state conditions is obtained， and the effect of the meshing force on the box body is analyzed. By using the Ansys， the analysis of the modal and dynamic response of the box is carried out， it shows that the peak vibration response is mainly concentrated at the fundamental frequency， double frequency， and double frequency of the gear meshing frequency， which arouses the resonance noise with the gear pair. In order to avoid the resonance zone， a scheme for optimizing the geometric parameters of the gear and improving the structure of the motor assembly is proposed without increasing the box space， and the optimization scheme is tested for noise. The results show that the combination scheme of optimizing gear geometric parameters and reinforcing the motor assembly is the best scheme， and the noise of the whole machine is reduced by about 8.9 dB. It has certain research significance and reference value for the optimization design and vibration and noise reduction of this type of product.

In traditional gear design, the design theory is based on a rigid hypothesis and is popularly adopted in the preparation of metal gear. Plastic gear designing lacks a mature design theory. Hence, scholars still follow the traditional gear design theory. There is a marked difference in the rigidity and stiffness between the conventional gear design and plastic gear features. In traditional design theory, the deformation is 0.2% (Note: To assess the material yield, conditional yield strength is calculated). Designing deformation can exceed 2% for plastic gears, and the difference can sometimes be more than tenfold. The traditional design theory cannot match the gear strength and precision in the design of plastic gear. In the case of plastic gear, due to numerous meshing teeth, the 2% deformation seen cannot be neglected and should be taken into account in the presence and absence of loading to improve the meshing condition. Improvement in the gear loading ability and reduction in the meshing noise can thus be achieved. Herein, we propose an unequal pitch design theory. The results of Finite Element Analysis (FEA) and experimental verification showed that the strength could be increased by 24% for unequal pitch design theory.

Hepatitis B virus (HBV) study is hampered by lacking of idea cell model which support effective HBV infection and meanwhile recapitulate hepatocyte biology function in vivo. In this study, we developed decellularized human liver scaffolds for cell culture and further applied for HBV infection. As a result, primary human hepatocytes (PHHs) engrafted into liver scaffolds and maintained differentiation with stable albumin secretion and liver‐specific gene expression. Comparing to mono‐layer cell culture, scaffold‐based three‐dimensional (3D) culture system significantly augment HBV DNA (including cccDNA), RNA level as well as HBsAg secretion. Moreover, HepG2‐NTCP cells cultured on 3D system exhibited higher infection efficiency and longer infection period in vitro. In addition, HBV DNA level was suppressed when anti‐HBV medicine Entecavir (ETV) introduced into HepG2‐NTCP 3D system. Herein, we evaluated the potential of decellularized human liver scaffold‐based in 3D cell culture and disclosed that scaffold‐based 3D culture system can facilitate HBV infection in vitro. This 3D culture system could be further applied in HBV‐related study. [ABSTRACT FROM AUTHOR]

This article proposes a novel lightweight attention spatiotemporal joint distribution adaptation network fault diagnosis model to address the key challenges of domain transfer and high model complexity in traditional methods. The novelty lies in 1. Using model compression techniques to reduce the complexity of the network model and improve its computational efficiency; 2. Introducing new domain adaptation and adversarial methods to solve the domain transfer problem. The effectiveness of the proposed model is verified through a transfer experiment of planetary gearbox vibration data. The experimental results show that the proposed model reduces the parameters and computational complexity to 18 % and 15 % of the original model, respectively, and has a diagnostic accuracy of over 98 % in cross-condition transfer tasks, and still maintains an accuracy of over 88 % even under high noise levels. This indicates that the proposed model is an efficient and accurate fault diagnosis model. [ABSTRACT FROM AUTHOR]