Search

Abstract Photothermal therapy (PTT) combined with second near-infrared (NIR-II) fluorescence imaging (FI) has received increasing attention owing to its capacity for precise diagnosis and real-time monitoring of the therapeutic effects. It is of great clinical value to study organic small molecular fluorophores with both PTT and NIR-II FI functions. In this work, we report a skillfully fluorescent lipid nanosystem, the RR9 (RGDRRRRRRRRRC) peptide-coated anionic liposome loaded with organic NIR-II fluorophore IR-1061 and chemotherapeutic drug carboplatin, which is named RRIALP-C4. According to the structural interaction between IR-1061 and phospholipid bilayer demonstrated by molecular dynamics simulations, IR-1061 is rationally designed to possess the H-aggregated state versus the free state, thus rendering RRIALP-C4 with the activated dual-channel integrated function of intravital NIR-II FI and NIR-I PTT. Functionalization of RRIALP-C4 with RR9 peptide endows the specifically targeting capacity for αvβ3-overexpressed tumor cells and, more importantly, allows IR-1061 to transfer the H-aggregated state from liposomes to the tumor cell membrane through enhanced membrane fusion, thereby maintaining its PTT effect in tumor tissues. In vivo experiments demonstrate that RRIALP-C4 can effectively visualize tumor tissues and systemic blood vessels with a high sign-to-background ratio (SBR) to realize the synergistic treatment of thermochemotherapy by PTT synergistically with temperature-sensitive drug release. Therefore, the strategy of enhanced PTT through H-aggregation of NIR-II fluorophore in the tumor cell membrane has great potential for developing lipid nanosystems with integrated diagnosis and treatment function.

The intricate mechanisms involved in the acquisition and translocation of polycyclic aromatic hydrocarbons (PAHs) in plants have not been elucidated. Phosphate (Pi) is the bioavailable form of essential macronutrient phosphorus, which is acquired and subsequently assimilated for plant optimal growth and development. Rice phosphate overaccumulator 2 (OsPHO2) is a central constituent of the regulation of Pi homeostasis in rice. In the present study, the role of OsPHO2 in regulating the translocation and accumulation of phenanthrene (Phe) and the involvement of Pi in this process were investigated. The temporal study (1 d-35 d) revealed a significant and gradual increase of Phe accumulation in Pi-deprived roots of wild-type (WT) seedlings. Compared with the WT, the concentrations of Phe were significantly higher in the shoots of ospho2 (OsPHO2 mutant) grown hydroponically with Phe (1.5 mg/L) under +Pi (200 μM) and -Pi (10 μM) conditions. The sap experiment clearly showed the significant increases in levels of Phe in the xylem sap of ospho2 than the WT grown hydroponically with Phe and +Pi. Further, the concentrations of both Phe and P were coordinately higher in the culms and flag leaves of the mutants than WT at maturity in potting soil with LPhe (6 mg/kg) and HPhe (60 mg/kg). However, the concentrations of Phe in the seeds were comparable in the WT and mutants, suggesting a pivotal of OsPHO2 in attenuating Phe toxicity in the seed. In +Phe WT, the relative expression level of OsPHO2 in the shoots was significantly lower, while those of Pi transporters (PTs) OsPT4 and OsPT8 were significantly higher in the roots compared with -Phe. Together, the results provided evidence towards the involvement of Pi in OsPHO2-regulated translocation and accumulation of Phe in rice.

The Bäcklund transformations are revisited for the Harry Dym equation. The associated nonlinear superposition formula, which consists of two equations — one for the field variable and the other for the spatial variable, is also presented. Interpreted as discrete systems, nonlinear superposition formula is identified as the lattice potential modified Korteweg–de Vries equation and a special case of Q1equation in the ABS list. A particular limit of the nonlinear superposition formula is considered and the resulting Bäcklund transformation is shown to be related to the finite transformation of the nonlocal symmetries.

To ensure the safety of excavations such as large section tunnels of the Guangxi Liubin Highway Tunnel Project, we implemented a simulation analysis of 3D tunnel models based on finite software for different construction methods. Different from the traditional simulation, this paper uses various construction methods to compare, study, and analyze the advantages and disadvantages of different excavation methods by combining them with the excavation. The feasibility of different construction methods was analyzed by studying the mechanical characteristics and settlement changes using the Cross Diaphragm (CRD), Center Diaphragm (CD), and full-section methods while building a large section tunnel. The arch perimeter deformation and surface settlement during the initial support and secondary lining proved that the CRD excavation method is the most favorable and causes the least damage to the stability of the surrounding rock. For the analysis of surface subsidence, the “V”-shaped surface subsidence curve excavated by the CRD method is the closest to the subsidence curve. However, we used the adjusted peak formula to fit the prediction formula for the surface settlement curve of the deep-buried two-lane tunnel with a large cross-section applicable to this project, which will provide an important reference for similar projects.

The in situ lactate oxidase (LOx) catalysis is highly efficient in reducing oxygen to H2O2 due to the abundant lactate substrate in the hypoxia tumor microenvironment. Dynamic therapy, including chemodynamic therapy (CDT), photodynamic therapy (PDT), and enzyme dynamic therapy (EDT), could generate reactive oxygen species (ROS) including ·OH and 1O2 through the disproportionate or cascade biocatalytic reaction of H2O2 in the tumor region. Here, we demonstrate a ROS-based tumor therapy by integrating LOx and the antiglycolytic drug Mito-LND into Fe3O4/g-C3N4 nanoparticles coated with CaCO3 (denoted as FGLMC). The LOx can catalyze endogenous lactate to produce H2O2, which decomposes cascades into ·OH and 1O2 through Fenton reaction-induced CDT and photo-triggered PDT. Meanwhile, the released Mito-LND contributes to metabolic therapy by cutting off the source of lactate and increasing ROS generation in mitochondria for further improvement in CDT and PDT. The results showed that the FGLMC nanoplatform can multifacetedly elevate ROS generation and cause fatal damage to cancer cells, leading to effective cancer suppression. This multidirectional ROS regulation strategy has therapeutic potential for different types of tumors.

According to fracture mechanics theory, the initial cracking law and wing crack propagation model of compression shear rock cracks subjected to hydraulic pressure and far field stresses are discussed. The results of the theoretical study show that crack initiation strength is inversely related to hydraulic pressure, that hydraulic pressure aggravates the wing crack’s growth, and that the wing crack’s behavior under high hydraulic pressure shifts from stable to unstable expansion. The confining pressure is proportional to the rock mass strength, the wing crack’s stress intensity factor drops as the remote field stress σ3 increases, and the wing crack tends to expand stably. As the crack angle increases, the cracking strength reduces at first, then increases. At the same time, damage fracture mechanics models are established for the occurrence of wing crack-wing crack failure, wing crack-shear crack failure, wing crack-shear crack-wing crack failure, and shear crack-shear crack failure in the compression-shear crack bridge under far-field stress and hydraulic pressure. The link between hydraulic pressure, confining pressure, fracture angle, stress intensity factor, and compression-shear factor λ12 is also clarified. The value of the stress intensity factor increases when the hydraulic pressure decreases, the confining pressure increases, and the crack angle increases, whereas the compression-shear factor decreases. This study lays the groundwork for a quantitative assessment of fractured rock mass destruction under hydraulic pressure.

Mitogen-activated protein kinases (MAPKs) play essential roles in mediating biotic and abiotic stress responses in plants. However, the MAPK gene family in strawberry has not been systematically characterized. Here, we performed a genome-wide survey and identified 12 MAPK genes in the Fragaria vesca genome. Protein domain analysis indicated that all FvMAPKs have typical protein kinase domains. Sequence alignments and phylogenetic analysis classified the FvMAPK genes into four different groups. Conserved motif and exon-intron organization supported the evolutionary relationships inferred from the phylogenetic analysis. Analysis of the stress-related cis-regulatory element in the promoters and subcellular localization predictions of FvMAPKs were also performed. Gene transcript profile analysis showed that the majority of the FvMAPK genes were ubiquitously transcribed in strawberry leaves after Podosphaera aphanis inoculation and after treatment with cold, heat, drought, salt and the exogenous hormones abscisic acid, ethephon, methyl jasmonate, and salicylic acid. RT-qPCR showed that six selected FvMAPK genes comprehensively responded to various stimuli. Additionally, interaction networks revealed that the crucial signaling transduction controlled by FvMAPKs may be involved in the biotic and abiotic stress responses. Our results may provide useful information for future research on the function of the MAPK gene family and the genetic improvement of strawberry resistance to environmental stresses.