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Programmed cell death ligand 2 (PD-L2), a ligand for the receptor programmed cell death 1 (PD-1), has an identity of 34% with its twin ligand PD-L1 and exhibits higher binding affinity with PD-1 than PD-L1. However, the role of PD-L2 in non-small cell lung cancer (NSCLC) progression, especially tobacco-induced cancer progression, has not been fully understood. Here, we found that PD-L2 promoted tumor growth in murine models with recruitment of regulatory T cells (Tregs). In patients with NSCLC, PD-L2 expression level in tumor samples was higher than in counterpart normal controls and was positively associated with patients' response to anti-PD-1 treatment. Mechanismly, PD-L2 bound its receptor Repulsive guidance molecule B (RGMB) on cancer cells and activated extracellular signal-regulated kinase (Erk) and nuclear factor κB (NFκB), leading to increased production of chemokine CCL20, which recruited Tregs and contributed to NSCLC progression. Consistently, knockdown of RGMB or NFκB p65 inhibited PD-L2-induced CCL20 production, and silencing of PD-L2 repressed Treg recruitment by NSCLC cells. Furthermore, cigarette smoke and carcinogen benzo(a)pyrene (BaP) upregulated PD-L2 in lung epithelial cells via aryl hydrocarbon receptor (AhR)-mediated transcription activation, whose deficiency markedly suppressed BaP-induced PD-L2 upregulation. These results suggest that PD-L2 mediates tobacco-induced recruitment of Tregs via the RGMB/NFκB/CCL20 cascade, and targeting this pathway might have therapeutic potentials in NSCLC. [ABSTRACT FROM AUTHOR]

The microstructural characterization of Basalt Fiber Reinforced Polymer (BFRP) bars under seawater deterioration (dry–wet cycles modes and immersion modes) was performed by scanning electron microscopy (SEM) and X-ray energy spectrum analyzer (EDS). Then, uniaxial compressive tests were carried out on the corroded BFRP bars to explore the effects of different corrosion periods, diameters, and slenderness ratios on the degradation of compressive performance and durability in seawater corrosion and constraint condition. The results showed that dry–wet cycles of seawater caused patchy pitting on the surfaces of BFRP bar, and white granular foams adhered to the bar surface after seawater immersion. The internal microstructure of BFRP bar was deteriorated, and the bonding force between the fiber and resin was reduced with the increase of dry–wet cycles. Five failure modes of BFRP bars occurred in uniaxial compressive tests, namely crushing failure, transverse cracking failure, shearing failure, splitting failure, and buckling failure. The increase of corrosion cycles significantly decreased the bearing capacity and compressive strength, but had little effect on the compressive elastic modulus of BFRP bars. The dry–wet cycles of seawater was more harmful to the mechanical properties of BFRP bars than immersion corrosion. Meanwhile, the mechanical properties of BFRP bars were affected by their diameters and slenderness ratios to some extent. [ABSTRACT FROM AUTHOR]

Neural implicit function based on signed distance field (SDF) has achieved impressive progress in reconstructing 3D models with high fidelity. However, such approaches can only represent closed surfaces. Recent works based on unsigned distance function (UDF) are proposed to handle both watertight and single-layered open surfaces. Nonetheless, as UDF is signless, its direct output is limited to the point cloud, which imposes an additional challenge on extracting high-quality meshes from discrete points. To address this challenge, we present a novel neural implicit representation coded HSDF, which is a hybrid of signed and unsigned distance fields. In particular, HSDF is able to represent arbitrary topologies containing both closed and open surfaces while being compatible with existing iso-surface extraction techniques for easy field-to-mesh conversion. In addition to predicting a UDF, we propose to learn an additional sign field. Unlike traditional SDF, HSDF is able to locate the surface of interest before level surface extraction by generating surface points following NDF [1]. We are then able to obtain open surfaces via an adaptive meshing approach that only instantiates regions containing surfaces into a polygon mesh. HSDF benefits downstream tasks like neural rendering, as it enables the rendering of back-faces of open surfaces. We also propose HSDF-Net, a dedicated learning framework that factorizes the learning of HSDF into two easier sub-problems. Experiments and evaluations show that HSDF outperforms the state-of-the-art techniques both qualitatively and quantitatively on some of the used datasets.

The Asian citrus psyllid (ACP) Diaphorina citri Kuwayama is the leading vector of Candidatus Liberibacter asiaticus ( C Las), the causative agent of citrus Huanglongbing (HLB) disease. The distribution and dynamics of C Las within ACP are critical to understanding how the transmission, spread and infection of C Las occurs within its host vector in nature. In this study, the distribution and titer changes of C Las in various tissues of ACP 5 th instar nymphs and adults were examined by fluorescence in situ hybridization (FISH) and real-time quantitative PCR (qPCR) techniques. Results demonstrated that 100% of ACP 5 th instar nymphs and adults were infected with C Las following feeding on infected plants, and that C Las had widespread distribution in most of the tissues of ACP. The titers of C Las within the midgut, salivary glands and hemolymph tissues were the highest in both 5 th instar nymphs and adults. When compared with adults, the titers of C Las in these three tissues of 5 th instar nymphs were significantly higher, while in the mycetome, ovary and testes they were significantly lower than those of adults. FISH visualization further confirmed these findings. Dynamic analysis of C Las demonstrated that it was present across all the developmental ages of ACP adults. There was a discernible upward trend in the presence of C Las with advancing age in most tissues of ACP adults, including the midgut, hemolymph, salivary glands, foot, head, cuticula and muscle. Our findings have significant implications for the comprehensive understanding of the transmission, dissemination and infestation of C Las, which is of much importance for developing novel strategies to halt the spread of C Las, and therefore contribute to the efficient prevention and control of HLB., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Guo, Kong, Mukangango, Hu, Liu, Sang and Qiu.)