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There are huge differences between tumor cells and normal cells in material metabolism, and tumor cells mainly show increased anabolism, decreased catabolism, and imbalance in substance metabolism. These differences provide the necessary material basis for the growth and reproduction of tumor cells, and also provide important targets for the treatment of tumors. Ferroptosis is an iron-dependent form of cell death characterized by an imbalance of iron-dependent lipid peroxidation and lipid membrane antioxidant systems in cells, resulting in excessive accumulation of lipid peroxide, causing damage to lipid membrane structure and loss of function, and ultimately cell death. The regulation of ferroptosis involves a variety of metabolic pathways, including glucose metabolism, lipid metabolism, amino acid metabolism, nucleotide metabolism and iron metabolism. In order for tumor cells to grow rapidly, their metabolic needs are more vigorous than those of normal cells. Tumor cells are metabolically reprogrammed to meet their rapidly proliferating material and energy needs. Metabolic reprogramming is mainly manifested in glycolysis and enhancement of pentose phosphate pathway, enhanced glutamine metabolism, increased nucleic acid synthesis, and iron metabolism tends to retain more intracellular iron. Metabolic reprogramming is accompanied by the production of reactive oxygen species and the activation of the antioxidant system. The state of high oxidative stress makes tumor cells more susceptible to redox imbalances, causing intracellular lipid peroxidation, which ultimately leads to ferroptosis. Therefore, in-depth study of the molecular mechanism and metabolic basis of ferroptosis is conducive to the development of new therapies to induce ferroptosis in cancer treatment. Ferroptosis, as a regulated form of cell death, can induce ferroptosis in tumor cells by pharmacologically or genetically targeting the metabolism of substances in tumor cells, which has great potential value in tumor treatment. This article summarizes the effects of cellular metabolism on ferroptosis in order to find new targets for tumor treatment and provide new ideas for clinical treatment.

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Camellia oleifera Abel. is an important woody oil species; however, the shortage of rapid and industrialized seedling culture is a large constraint on the development of the tea oil industry. Somatic embryogenesis (SE) is one of the main powerful biotechnological tools for plant mass regeneration, but the largely unknown SE in C. oleifera limits the scale production of clonal plants. In this study, we described a high-efficiency SE system via direct and indirect pathways in C. oleifera and investigated the effect of genotype, explant age and phytohormones on SE. In the direct pathway, somatic embryos were highly induced from immature seeds 220 days after full blossom, and the development of embryoids was achieved with a combination of 0.19 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.05 mg/L thidiazuron (TDZ). In the indirect pathway, embryogenic calli were induced from the same explants in medium containing 1.5 mg/L 2,4-D, while 0.75 mg/L 2,4-D treatment led to high proliferation rates for embryogenic calli. The addition of 0.19 mg/L 2,4-D alone stimulated the production of globular embryos while causing a 75% loss of the induction rate in the heart embryo stage. Upon transfer of the globular embryos to phytohormone-free medium, an optimal induction rate of 62.37% from globular embryos to cotyledonary embryos was obtained. These data suggest that the subsequent differentiation process after the globular embryo stage in ISE is more similar to an endogenous phytohormones-driven process. Mature embryos germinated to produce intact plantlets on half-strength MS basal medium with a regeneration rate of 63.67%. Histological analysis confirmed the vascular bundle isolation of embryoids from the mother tissue. We further studied the different varieties and found that there were no significant genotype differences for SE induction efficiency in C. oleifera. Thus, we established a high-efficiency induction system for direct and indirect somatic embryogenesis (ISE) in C. oleifera and regenerated intact plantlets via SE, not organogenesis. ISE has a more complicated induction and regulatory mechanism than direct somatic embryogenesis. The improved protocol of SE would benefit mass propagation and genetic manipulation in C. oleifera.

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<p><b>OBJECTIVE</b>To test the effect of recombinant interleukin-4 (IL-4) and recombinant osteoprotegerin (OPG) in suppressing bone resorption induced by polyethylene wear particles..</p><p><b>METHODS</b>A cranial bone allograft was introduced into the air pouches induced on the back of BALB/c mice, followed by injection of 1 ml suspension of polyethylene particles into the pouches. The mouse models were then divided into 3 groups to receive injections of saline (control), IL-4 alone, or IL-4 and OPG into the pouches. The tissues were harvested 21 days after bone implantation for molecular and histological analyses.</p><p><b>RESULTS</b>Polyethylene wear particles-stimulated inflammatory responses (increased cellular infiltration and IL-1 and TNF production) were markedly reduced by IL-4 treatment either alone or combined with OPG (P<0.05). Polyethylene particles significantly increased tartrate-resistant acid phosphatase (TRAP) staining and bone absorption of the implanted bone graft, and IL-4 treatment, either alone or combined with OPG, obviously reduced the osteolysis induced by polyethylene particles (P<0.05).</p><p><b>CONCLUSION</b>IL-4 offers protection against polyethylene wear debris-induced inflammation and bone resorption in this mouse model. IL-4 combined with OPG can be a feasible and effective therapeutic approach to the treatment and prevention of polyethylene wear debris-associated osteolysis and aseptic loosening of the prosthetic components.</p>

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The proposed registration algorithm based on wavelet transform is a multi-resolution block matching one, which exploits the hierarchical self-similarity of Digital Subtraction Angiography images. This method befittingly trades off between the estimation precision and computational complexity, because the registration precision is from coarse to fine, which reduces the searching complexity of motion vector. This technique has been proved that the convergence speed is exponential. The proposed method takes full advantage of the precise location both temporally and frequently which characterizes the wavelet transform. Both the matching speed and consistency are boosted without the loss of matching performance.

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How to eliminate the background of other tissue and to protrude the blood vessel information is the basic requirements in DSA. Because of the complexity and non-linearity of the X-ray imaging process, the common DSA technique cannot completely remove other tissue's image which lapped over the vessels. By experiments, this paper analyses and corrects the imaging process of the actual DSA system based on the "equivalent single energy" model, and the results indicate the validity of this method.

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