Characterization and antitumor activity of camptothecin from endophytic fungus Fusarium solani isolated from Camptotheca acuminate

Background: Camptothecin (CPT) is a potent drug against cancers, originally from plants. The endophytic fungi could produce the secondary metabolite same as the host and is used as medicine.Objectives: The aim of this paper was to investigate an endophytic fungal CPT with anti-neoplastic activity.Methods: Endophytic fungi were isolated from Camptotheca acuminata in China. CPT from strain S-019 was characterized by TLC, HPLC and EI-MS analysis. Anti-tumor activity of fungal CPT was detected by MTT and fluorescent dye methods using Vero and PC-3 cells.Results: A total of 94 endophytic fungi strains were isolated from tissues of C. acuminata and 16 fungi strains displayed cytotoxic activity on Vero or PC3 cells. Of which, the fungal strain S-019, classified as Fusarium solani, displayed impressive cytotoxic activity on cancer cells and was found to produce CPT by analysis of TLC, HPLC and EI-MS methods. Bioassay studies confirmed that the fungi CPT had potent cytotoxicity on Vero cells and induced apoptosis of Vero cells.Conclusion: The endophytic fungi from camptotheca trees are a reliable source for natural anticancer compounds. The endophytic fungi could produce CPT same as plant. The fungal CPT exhibited effective activity at inhibiting cell growth and inducing apoptosis on Vero cells.Keywords: Endophytic fungi, camptothecin, anti-tumor, Camptotheca acuminat

Circular Accessible Depth: A Robust Traversability Representation for UGV Navigation

In this paper, we present the Circular Accessible Depth (CAD), a robust traversability representation for an unmanned ground vehicle (UGV) to learn traversability in various scenarios containing irregular obstacles. To predict CAD, we propose a neural network, namely CADNet, with an attention-based multi-frame point cloud fusion module, Stability-Attention Module (SAM), to encode the spatial features from point clouds captured by LiDAR. CAD is designed based on the polar coordinate system and focuses on predicting the border of traversable area. Since it encodes the spatial information of the surrounding environment, which enables a semi-supervised learning for the CADNet, and thus desirably avoids annotating a large amount of data. Extensive experiments demonstrate that CAD outperforms baselines in terms of robustness and precision. We also implement our method on a real UGV and show that it performs well in real-world scenarios.Comment: 13 pages, 8 figure

Characterization and antitumor activity of camptothecin from endophytic fungus Fusarium solani isolated from Camptotheca acuminate .

Background: Camptothecin (CPT) is a potent drug against cancers, originally from plants. The endophytic fungi could produce the secondary metabolite same as the host and is used as medicine. Objectives:The aim of this paper was to investigate an endophytic fungal CPT with anti-neoplastic activity. Methods: Endophytic fungi were isolated from Camptotheca acuminata in China. CPT from strain S-019 was characterized by TLC, HPLC and EI-MS analysis. Anti-tumor activity of fungal CPT was detected by MTT and fluorescent dye methods using Vero and PC-3 cells. Results: A total of 94 endophytic fungi strains were isolated from tissues of C. acuminata and 16 fungi strains displayed cytotoxic activity on Vero or PC3 cells. Of which, the fungal strain S-019, classified as Fusarium solani, displayed impressive cytotoxic activity on cancer cells and was found to produce CPT by analysis of TLC, HPLC and EI-MS methods. Bioassay studies confirmed that the fungi CPT had potent cytotoxicity on Vero cells and induced apoptosis of Vero cells. Conclusion: The endophytic fungi from camptotheca trees are a reliable source for natural anticancer compounds. The endophytic fungi could produce CPT same as plant. The fungal CPT exhibited effective activity at inhibiting cell growth and inducing apoptosis on Vero cells

Study on the Effects of Innovative Curing Combinations on the Early Temperature Field of Concrete Box Girders

Box girder bridges are often subject to cracking due to wet temperature changes caused by the heat of hydration in the early stages; however, current studies do not provide an effective method for considering this effect. The reasonable temperature control of concrete box girders can prevent early concrete cracking and ensure concrete quality, but box girder temperature control becomes an important focus in construction. To fill this gap, a two-dimensional temperature field study was carried out for a large-span box bridge by the finite element method. The advantages and disadvantages of the two innovative combination curing methods and the early curing effects on the construction of a box girder in summer were investigated and analyzed based on the temperature field of the box girder under different curing methods, the time–history curves of the temperature at each key node of the box girder, and the time–history curves of the temperature difference between the inside and outside of the box girder. The research results show that the mold paste and automatic water spray method (Combination B method) is more suitable for the early curing of box girders in summer

Study on the Effects of Innovative Curing Combinations on the Early Temperature Field of Concrete Box Girders

Box girder bridges are often subject to cracking due to wet temperature changes caused by the heat of hydration in the early stages; however, current studies do not provide an effective method for considering this effect. The reasonable temperature control of concrete box girders can prevent early concrete cracking and ensure concrete quality, but box girder temperature control becomes an important focus in construction. To fill this gap, a two-dimensional temperature field study was carried out for a large-span box bridge by the finite element method. The advantages and disadvantages of the two innovative combination curing methods and the early curing effects on the construction of a box girder in summer were investigated and analyzed based on the temperature field of the box girder under different curing methods, the time–history curves of the temperature at each key node of the box girder, and the time–history curves of the temperature difference between the inside and outside of the box girder. The research results show that the mold paste and automatic water spray method (Combination B method) is more suitable for the early curing of box girders in summer

Rational Design of Lewis Base Electron Transport Materials for Improved Interface Property in Inverted Perovskite Solar Cells: A Theoretical Investigation

Electron transport materials (ETMs) play a vital role in electron extraction and transport at the perovskite/ETM interface of inverted perovskite solar cells (PSCs) and are useful in power conversion efficiency (PCE), which is limited by interface carrier recombination. However, strategies for passivating undercoordinated Pb2+ at the perovskite/ETM interface employing ETMs remain a challenge. In this work, a variety of heteroatoms were used to strengthen the Lewis base property of new ETMs (asymmetrical perylene-diimide), aimed at deactivating non-bonded Pb2+ at the perovskite surface through Lewis acid-base coordination. Quantum chemical analysis revealed that novel ETMs have matched the energy level of perovskite, which enables electron extraction at the perovskite/ETM interface. The results also suggest that the large electron mobility (0.57~5.94 cm2 V−1 s−1) of designed ETMs shows excellent electron transporting ability. More importantly, reinforced interaction between new ETMs and Pb2+ was found, which is facilitating to passivation of the defects induced by unsaturated Pb2+ at the perovskite/ETM interface. Furthermore, it is found that MA (CH3NH3+), Pb, and IPb (iodine substituted on the Pb site) defects at the perovskite/ETM interface could be effectively deactivated by the new ETMs. This study provides a useful strategy to design ETMs for improving the interface property in PSCs

miR-103-3p Regulates the Differentiation and Autophagy of Myoblasts by Targeting MAP4

Skeletal muscle is the most abundant tissue in mammals, and myogenesis and differentiation require a series of regulatory factors such as microRNAs (miRNAs). In this study, we found that miR-103-3p was highly expressed in the skeletal muscle of mice, and the effects of miR-103-3p on skeletal muscle development were explored using myoblast C2C12 cells as a model. The results showed that miR-103-3p could significantly reduce myotube formation and restrain the differentiation of C2C12 cells. Additionally, miR-103-3p obviously prevented the production of autolysosomes and inhibited the autophagy of C2C12 cells. Moreover, bioinformatics prediction and dual-luciferase reporter assays confirmed that miR-103-3p could directly target the microtubule-associated protein 4 (MAP4) gene. The effects of MAP4 on the differentiation and autophagy of myoblasts were then elucidated. MAP4 promoted both the differentiation and autophagy of C2C12 cells, which was contrary to the role of miR-103-3p. Further research revealed that MAP4 colocalized with LC3 in C2C12 cell cytoplasm, and the immunoprecipitation assay showed that MAP4 interacted with autophagy marker LC3 to regulate the autophagy of C2C12 cells. Overall, these results indicated that miR-103-3p regulated the differentiation and autophagy of myoblasts by targeting MAP4. These findings enrich the understanding of the regulatory network of miRNAs involved in the myogenesis of skeletal muscle