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Parkinson’s disease (PD) is second most common neurodegenerative disorder worldwide. Although drugs and surgery can relieve the symptoms of PD, these therapies are incapable of fundamentally treating the disease. For PD patients, over-expression of α-synuclein (SNCA) leads to the death of dopaminergic neurons. This process can be prevented by suppressing SNCA over-expression through RNA interference. Here, we successfully synthesized gold nanoparticles (GNP) composites (CTS@GNP-pDNA-NGF) via the combination of electrostatic adsorption and photochemical immobilization, which could load plasmid DNA (pDNA) and target specific cell types. GNP was transfected into cells via endocytosis to inhibiting the apoptosis of PC12 cells and dopaminergic neurons. Simultaneously, GNP composites are also used in PD models in vivo, and it can successfully cross the blood-brain barrier by contents of GNP in the mice brain. In general, all the works demonstrated that GNP composites have good therapeutic effects for PD models in vitro and in vivo.  相似文献   
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Gas transport concepts in vertebrates have naturally been formulated based on human blood. However, the first vertebrates were aquatic, and fish and tetrapods diverged hundreds of millions years ago. Water‐breathing vertebrates live in an environment with low and variable O2 levels, making environmental O2 an important evolutionary selection pressure in fishes, and various features of their gas transport differ from humans. Erythrocyte function in fish is of current interest, because current environmental changes affect gas transport, and because especially zebrafish is used as a model in biomedical studies, making it important to understand the differences in gas transport between fish and mammals to be able to carry out meaningful studies. Of the close to thirty thousand fish species, teleosts are the most species‐numerous group. However, two additional radiations are discussed: agnathans and elasmobranchs. The gas transport by elasmobranchs may be closest to the ancestors of tetrapods. The major difference in their haemoglobin (Hb) function to humans is their high urea tolerance. Agnathans differ from other vertebrates by having Hbs, where cooperativity is achieved by monomer‐oligomer equilibria. Their erythrocytes also lack the anion exchange pathway with profound effects on CO2 transport. Teleosts are characterized by highly pH sensitive Hbs, which can fail to become fully O2‐saturated at low pH. An adrenergically stimulated Na+/H+ exchanger has evolved in their erythrocyte membrane, and plasma‐accessible carbonic anhydrase can be differentially distributed among their tissues. Together, and differing from other vertebrates, these features can maximize O2 unloading in muscle while ensuring O2 loading in gills.  相似文献   
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The objective of this article is to evaluate whether the tumoricidal activity of mouse IFN R−/− nature killer (NK) cells is induced by Newcastle disease virus hemagglutinin-neuraminidase (NDV-HN) stimulation, and to investigate what is the mechanism of the HN-stimulated NK cells to kill mouse hepatoma cell line in vitro. The mouse IFN R−/− NK cells were stimulated for 16 hr with 500 ng/mL NDV-HN in 1640 medium. Quantify the cytotoxic activities of NK cells against mouse hepatoma cells (Hepa1-6) by flow cytometry. Granzymes B (GrB) and Fas/FasL concentrations in the supernatants of IFN R−/− NK cells medium were determined by specific ELISA assay. The expression of cell surface GrB and Fas was determined by Western blot. NDV-HN stimulation enhanced tumoricidal activity of IFN R−/− NK cells toward Hepa1-6 in vitro. Treating with anti-HN neutralizing mAb induced significant decline in the cytotoxicity of IFN R−/− NK cells toward Hepa1-6 cell line (P < 0.05). After treating with anti-HN protein (1 μL/mL), Syk-specific inhibitor Herbimycin A(250 ng/mL) and NF-κB inhibitor PDTC (500 ng/mL) downregulated the tumoricidal activity of HN-stimulated IFN R−/− NK cells (P < 0.05). Moreover, significant suppressions in the production of GrB and Fas/FasL were observed in HN-stimulated IFN R−/− NK cells (P < 0.05). Thus, we concluded that killer activation receptors pathway is involved in the IFN-γ-independent GrB and Fas/FasL expression of NDV-HN-stimulated IFN R−/− NK cells, and these are activated by Syk and NF-κB. Anat Rec, 302:1718–1725, 2019. © 2019 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association for Anatomy  相似文献   
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