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Clustered regularly interspaced short palindromic repeats/associated protein 9 (CRISPR/Cas9)-based therapies are attractive to achieve precise and targeted disruption of the hepatitis B virus (HBV) genome for HBV infection treatment. However, unspecific in vivo distribution of the CRISPR/Cas9 vector after systemic administration not only impedes CRISPR/Cas9 expression in the liver, but also causes undesired gene editing in off-site organs, decreasing the therapeutic efficacy and leading to potential side effects. Herein, we designed a hepatocyte-confined CRISPR/Cas9-based nanocleaver (HepCCCleaver) to realize precise and efficient cleavage of HBV DNA, specifically in hepatocytes, for safe and effective HBV treatment. This HepCCCleaver was formed by encapsulating the hepatocyte-specific CRISPR/Cas9 plasmid into a galactose-modified membrane-fusogenic carrier. Our galactose-modified membrane-fusogenic carrier allowed the HepCCCleaver to specifically accumulate in the liver and enter hepatocytes through membrane fusion, bypassing lysosome entrapment to avoid degradation for superior delivery efficiency. The hepatocyte-specific CRISPR/Cas9 plasmid released in the cytoplasm could switch on the gene expression only in hepatocytes, ensuring precise cleavage on viral DNA in HBV-infected but not other types of cells. By integrating the liver-targeting membrane-fusogenic delivery system with hepatocyte-specific CRISPR/Cas9 plasmid, this HepCCCleaver could precisely and efficiently confine over 95% events of viral DNA gene editing in hepatocytes. This HepCCCleaver is a universal gene editing platform enabling safe and efficient disease treatment, specifically in the cell type of interest. [Display omitted] • A hepatocyte-specific chimeric promoter is constructed into a hepatocyte-specifically-activated CRISPR/Cas9 plasmid. • HepCCCleaver can perform membrane-fusion-mediated delivery to achieve efficient gene transfection. • HepCCCleaver can confine CRISPR/Cas9 gene editing in hepatocyte, achieving safe and effective HBV treatment. [ABSTRACT FROM AUTHOR]

Abstract: An error estimate is presented for the numerical approximation to an exterior problem of the Poisson equation when a coupled finite–infinite element method is employed in the computation. This estimate involves not only the size h and the order p of the quasiuniform finite element approximation, but also the radius R of the computational domain covered with finite elements and the number N of the radial terms of infinite elements. Numerical tests are performed, and the results partly validate the theoretical analysis. [Copyright &y& Elsevier]

The mixed finite element method is used to solve the exterior elliptic problem with high-order local artificial boundary conditions. New unknowns are introduced to reduce the order of the derivatives to two. This leads to an equivalent mixed variational problem such that the normal finite element can be used and special finite elements are no longer needed on the adjacent layer of the artificial boundary. Error estimates are obtained for some local artificial boundary conditions with prescribed order. Numerical examples are presented and the results demonstrate the effectiveness of this method. [Copyright &y& Elsevier]

Targeting the activated epidermal growth factor receptor (EGFR) via clustered regularly interspaced short palindromic repeat (CRISPR) technology is appealing to overcome the drug resistance of hepatocellular carcinoma (HCC) towards tyrosine kinase inhibitor (TKI) therapy. However, combining these two distinct drugs using traditional liposomes results in a suboptimal synergistic anti-HCC effect due to the limited CRISPR/Cas9 delivery efficiency caused by lysosomal entrapment after endocytosis. Herein, we developed a liver-targeting gene-hybridizing-TKI fusogenic liposome (LIGHTFUL) that can achieve high CRISPR/Cas9 expression to reverse the EGFR-mediated drug resistance for enhanced TKI-based HCC therapy efficiently. Coated with a galactose-modified membrane-fusogenic lipid layer, LIGHTFUL reached the targeting liver site to fuse with HCC tumor cells, directly and efficiently transporting interior CDK5- and PLK1-targeting CRISPR/Cas9 plasmids (pXG333-CPs) into the HCC cell cytoplasm and then the cell nucleus for efficient expression. Such membrane-fusion-mediated pXG333-CP delivery resulted in effective downregulation of both CDK5 and PLK1, sufficiently inactivating EGFR to improve the anti-HCC effects of the co-delivered TKI, lenvatinib. This membrane-fusion-participant codelivery strategy optimized the synergetic effect of CRISPR/Cas9 and TKI combinational therapy as indicated by the 0.35 combination index in vitro and the dramatic reduction of subcutaneous and orthotopic TKI-insensitive HCC tumor growth in mice. Therefore, the established LIGHTFUL provides a unique co-delivery platform to combine gene editing and TKI therapies for enhanced synergetic therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

The reconstruction of a penetrable obstacle embedded in a periodic waveguide is a challenging problem. In this paper, the inverse problem is formulated as an optimization problem. We prove some properties of the scattering operator and propose an iterative scheme to approximate the support of the obstacle. Using the limiting absorption principle and a recursive doubling technique, we implement a fast algorithm based on a carefully designed finite element method for the forward scattering problem. Numerical examples validate the effectiveness of the method. [ABSTRACT FROM AUTHOR]

Immunotherapy through the activation of the stimulator of interferon genes (STING) signaling pathway is increasingly recognized for its robust anti-tumor efficacy. However, the effectiveness of STING activation is often compromised by inadequate anti-tumor immunity and a scarcity of primed immune cells in the tumor microenvironment. Herein, we design and fabricate a co-axial 3D-printed scaffold integrating a non-nucleotide STING agonist, SR-717, and an AKT inhibitor, MK-2206, in its respective shell and core layers, to synergistically enhance STING activation, thereby suppressing tumor recurrence and growth. SR-717 initiates the STING activation to enhance the phosphorylation of the factors along the STING pathway, while MK-2206 concurrently inhibits the AKT phosphorylation to facilitate the TBK1 phosphorylation of the STING pathway. The sequential and sustained release of SR-717 and MK-2206 from the scaffold results in a synergistic STING activation, demonstrating substantial anti-tumor efficacy across multiple tumor models. Furthermore, the scaffold promotes the recruitment and enrichment of activated dendritic cells and M1 macrophages, subsequently stimulating anti-tumor T cell activity, thereby amplifying the immunotherapeutic effect. This precise and synergistic activation of STING by the scaffold offers promising potential in tumor immunotherapy. [Display omitted] • The co-axial 3D-printed scaffold facilitates the spatiotemporal release of drugs. • The spatiotemporally released SR-717 and MK-2206 enhance STING activation. • The scaffold serves as excellent artificial lymph node for local immunotherapy. [ABSTRACT FROM AUTHOR]