27 research outputs found
Investigating the immune mechanism of natural products in the treatment of lung cancer
With the deepening of people’s understanding of lung cancer, the research of lung cancer immunotherapy has gradually become the focus of attention. As we all know, the treatment of many diseases relies on the rich sources, complex and varied compositions and wide range of unique biological properties of natural products. Studies have shown that natural products can exert anticancer effects by inducing tumor cell death, inhibiting tumor cell proliferation, and enhancing tumor cell autophagy. More notably, natural products can adjust and strengthen the body’s immune response, which includes enhancing the function of NK cells and promoting the differentiation and proliferation of T lymphocytes. In addition, these natural products may enhance their anticancer effects by affecting inhibitory factors in the immune system, hormone levels, enzymes involved in biotransformation, and modulating other factors in the tumor microenvironment. The importance of natural products in lung cancer immunotherapy should not be underestimated. However, the specific links and correlations between natural products and lung cancer immunity are not clear enough, and further studies are urgently needed to clarify the relationship between the two. In this paper, we will focus on the correlation between natural products and lung cancer immune responses, with a view to providing new research perspectives for immunotherapy of lung cancer
Non-inverse kinematics of free-floating space robot based on motion planning of sampling
Motion planning is one of the fundamental technologies for robots to achieve autonomy. Free-floating space robots composed manipulators and base satellite that do not actively control its position and attitude has nonholonomic characteristics, and there is a first-order differential relationship between its joint angle and the base attitude. In addition, the planning framework which first converts the goal end-effector pose to its corresponding target configuration, and then plan the trajectory from the initial configuration to the goal configuration still has the following problems: the goal configuration and the initial configuration may not be in the same connected domain. Based on the RRT framework, the motion planning of a free-floating space robot from the initial configuration to the goal end-effector pose is studied. In the algorithm design, in order to deal with the differential constraints of the free-floating space robot, and the requirement that the attitude disturbance of its base cannot exceed its limit, a control-based local planner for random configuration guiding growth of the tree and a control-based local planner for goal end-effector pose guiding growth of the tree that can adjust the attitude of the base when necessary are proposed. The former can ensure the effective exploration of the configuration space, and the latter can avoid the occurrence of singularity while ensuring that the algorithm converges quickly and the base attitude disturbance meets the constraints. The present algorithm does not need to solve the inverse kinematics, can successfully complete the planning task, and ensure that the base attitude disturbance meets the requirements. The simulation verifies the effectiveness of the algorithm
A NEW METHOD TO PREPARE THE NOVEL ANATASE TiO2
In this paper, a kind of novel anatase TiO2 nanoparticle with single-electron-trapped oxygen vacancies was prepared by hydrothermal treated nanotube titanic acid. The morphology, structure, and properties of the products were characterized by transmission electron microscope, X-ray diffraction, electron spin resonance, and photoluminescence. Photocatalytic decolorization of the Methylene Blue solution was carried out in the visible light region and showed a high photocatalytic activity.Nanotube titanic acid, novel TiO2, single-electron-trapped oxygen vacancies, hydrothermal method
The establishment and verification of kinematic equation of all link centroid of the manipulator mounted on a satellite
(-)-Epicatechin attenuates hepatic sinusoidal obstruction syndrome by inhibiting liver oxidative and inflammatory injury
Hepatic sinusoidal obstruction syndrome (HSOS) is a rare liver disease with considerable morbidity and mortality. (-)-Epicatechin (EPI) is a natural flavonol. This study aims to investigate the protection of EPI against monocrotaline (MCT)-induced HSOS and its engaged mechanism. Results of serum alanine/aspartate aminotransferases (ALT/AST) activities, total bilirubin (TBil) and bile acids (TBA) amounts, liver histological evaluation, scanning electron microscope observation and hepatic metalloproteinase-9 (MMP-9) expression all demonstrated the protection by EPI against MCT-induced HSOS in rats. EPI attenuated liver oxidative injury induced by MCT. EPI enhanced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and increased the expression of its downstream antioxidant genes in rats. Molecular docking results implied the potential interaction of EPI with the Nrf2 binding site in kelch-like ECH-associated protein-1 (Keap1). The EPI-provided protection against MCT-induced HSOS was diminished in Nrf2 knock-out mice when mice were treated with MCT for 24 h but not for 48 h. However, EPI reduced the increased liver myeloperoxidase (MPO) activity, hepatic infiltration of immune cells, pro-inflammatory cytokines expression and nuclear factor κB (NFκB) activation in both wild-type and Nrf2 knock-out mice when mice were treated with MCT for 48 h. EPI reduced the elevated serum heat shock protein 60 (HSP60) content, and reversed the decreased mitochondria expression of HSP60 and Lon in livers from MCT-treated rats. Furthermore, the MCT-induced HSOS was markedly alleviated in mice treated with anti-HSP60 antibody. Taken together, this study demonstrates that EPI attenuates MCT-induced HSOS by reducing liver oxidative injury via activating Nrf2 antioxidant pathway and inhibiting liver inflammatory injury through abrogating NFκB signaling pathway initiated by HSP60. Keywords: (-)-Epicatechin, Monocrotaline, HSOS, Nrf2, NFκ
Smart Mesoporous SiO<sub>2</sub> Nanoparticles for the DNAzyme-Induced Multiplexed Release of Substrates
The fluorescent dyes methylene blue, MB<sup>+</sup>,
and thionine,
Th<sup>+</sup>, can be trapped in the pores of mesoporous silica,
MP-SiO<sub>2</sub>, by means of functional nanostructures consisting
of the Mg<sup>2+</sup>- or Zn<sup>2+</sup>-dependent DNAzyme sequences.
In the presence of Mg<sup>2+</sup> or Zn<sup>2+</sup> ions the respective
DNAzymes are activated, leading to the specific cleavage of the respective
caps, and the selective release of MB<sup>+</sup> or Th<sup>+</sup>. The enlargement of the conserved loop domains of the Mg<sup>2+</sup>- or Zn<sup>2+</sup>-dependent DNAzyme sequences with foreign nucleotides
prohibits the formation of active DNAzymes and eliminates the release
of the respective dyes. This is due to the flexibility of the loops
that lacks affinity for the association of the ions. The insertion
of aptamer sequences (e.g., the adenosine-5′-triphosphate (ATP)
aptamer) or ion-binding sequences (e.g., T-rich Hg<sup>2+</sup> ion-binding
domains) as foreign components to the loop regions allows the formation
of active Mg<sup>2+</sup>- or Zn<sup>2+</sup>-dependent DNAzyme structures
through the cooperative formation of aptamer-ATP complexes or T-Hg<sup>2+</sup>-T bridges. These aptamer–substrate complexes or T-Hg<sup>2+</sup>-T bridges allosterically stabilize and activate the DNAzymes,
thus allowing the selective release of the fluorescent substrates
MB<sup>+</sup> or Th<sup>+</sup>. The metal ion-driven DNAzyme release
of substrates from the pores of MP-SiO<sub>2</sub>, and particularly
the allosteric activation of the DNAzymes through cooperative aptamer–substrate
complexes or metal-ion bridges, has important future nanomedical implications
for targeted release of drugs. This is demonstrated with the triggered
release of the anticancer drug, doxorubicin, by the Mg<sup>2+</sup>-DNAzyme-locked pores or by the aptamer-ATP complex-triggered activation
of the Mg<sup>2+</sup>-dependent DNAzyme
Table1_Investigating the immune mechanism of natural products in the treatment of lung cancer.XLSX
With the deepening of people’s understanding of lung cancer, the research of lung cancer immunotherapy has gradually become the focus of attention. As we all know, the treatment of many diseases relies on the rich sources, complex and varied compositions and wide range of unique biological properties of natural products. Studies have shown that natural products can exert anticancer effects by inducing tumor cell death, inhibiting tumor cell proliferation, and enhancing tumor cell autophagy. More notably, natural products can adjust and strengthen the body’s immune response, which includes enhancing the function of NK cells and promoting the differentiation and proliferation of T lymphocytes. In addition, these natural products may enhance their anticancer effects by affecting inhibitory factors in the immune system, hormone levels, enzymes involved in biotransformation, and modulating other factors in the tumor microenvironment. The importance of natural products in lung cancer immunotherapy should not be underestimated. However, the specific links and correlations between natural products and lung cancer immunity are not clear enough, and further studies are urgently needed to clarify the relationship between the two. In this paper, we will focus on the correlation between natural products and lung cancer immune responses, with a view to providing new research perspectives for immunotherapy of lung cancer.</p
A numerical coupling method for particle tracking in electromagnetic fields
With the arrival of the information age, the electromagnetic energy in space increases constantly, resulting in the influence of electromagnetic waves on the charged aerosol particles in the environment which should be taken into account. Here, a numerical coupling method based on temporal and spatial scales is proposed to solve the difficulty in obtaining the trajectory of particles under the action of high-frequency electromagnetic waves. In the temporal scale, two constant forces with linear relationship are used to equilibrate the electromagnetic field forces under different conditions, however the above-mentioned equivalent method has the space limitation; in addition, on the spatial scale, the model with larger geometry should be divided into multiple basic modules spatially, the domain division method is adopted and due to the above method it can be used well in the basic module. Verified the correctness through the comparison of the results, and compared with the traditional method, the above method greatly reduces the computational complexity. Some interesting results were obtained by calculating the modulated waves with the above method, which indicate that special forms of electromagnetic waves will significantly affect the motion of particles
Biocatalytic Release of an Anticancer Drug from Nucleic-Acids-Capped Mesoporous SiO<sub>2</sub> Using DNA or Molecular Biomarkers as Triggering Stimuli
DNA-gated mesoporous SiO<sub>2</sub> nanoparticles, MP-SiO<sub>2</sub> NPs, loaded with rhodamine B, RhB, act as “smart” materials that reveal complementary “sense” and “release” functionalities. The unlocking of the DNA pore-capping units is achieved by the biocatalytic cleavage of the DNA, and the unlocking process is amplified by the regeneration of the analyte-trigger. The RhB-loaded MP-SiO<sub>2</sub> NPs are capped with nucleic acid hairpin structures that lock the RhB in the pores. Opening of the hairpin structures by a nucleic acid analyte trigger or by the formation of an aptamer–substrate (ATP) complex leads to the formation of duplex structures being cleaved by exonuclease III, Exo III, or the nicking enzyme, Nb. BbvCI. This results in the regeneration of the target analytes, the autonomous unlocking of the pores, and the release of RhB. The systems reveal selectivity, and one-, two-, three-base mutations in the target DNA, or substitution of ATP with other triphosphate nucleotides, prohibit the unlocking of the pores. In analogy to the biocatalytic release of the model fluorophore substrates, the anticancer drug camptothecin, CPT, was entrapped in the pores and locked by the <b>1</b> or <b>11</b> hairpin structures. The drug was released from the pores in the presence of the nucleic acid <b>2</b> or ATP and the Exo III, as biocatalyst. Similarly, CPT locked in the pores by the <b>6</b> or <b>12</b> hairpins were released from the pores in the presence of ATP and Nb. BbvCI, as nicking enzyme, respectively. The effects of the CPT-loaded MP-SiO<sub>2</sub> NPs, capped with the ATP-dependent lock <b>6</b>, on the viability of MDA-231 breast cancer cells and MCF-10a normal breast cells were examined. We find that after 48 h, 65% cell death was observed for the MDA-231 cancer cells, where only 25% cell death was observed for the normal cells. The higher cell death of the cancer cells correlates well with the enhanced metabolic synthesis of ATP in the cancerous cells