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31.
A series of 5,6-dimethoxybenzo[d]isothiazol-3(2H)-one-N-alkylbenzylamine derivatives were designed, synthesized and evaluated as potential multifunctional agents for the treatment of Alzheimer’s disease (AD). The in vitro assays indicated that most of these derivatives were selective AChE inhibitors with good multifunctional properties. Among them, compounds 11b and 11d displayed comprehensive advantages, with good AChE (IC50?=?0.29?±?0.01?μM and 0.46?±?0.02?μM, respectively), MAO-A (IC50?=?8.2?±?0.08?μM and 7.9?±?0.07?μM, respectively) and MAO-B (IC50?=?20.1?±?0.16?μM and 43.8?±?2.0% at 10?μM, respectively) inhibitory activities, moderate self-induced Aβ1–42 aggregation inhibitory potency (35.4?±?0.42% and 48.0?±?1.53% at 25?μM, respectively) and potential antioxidant activity. In addition, the two representative compounds displayed high BBB permeability in vitro. Taken together, these multifunctional properties make 11b and 11d as a promising candidate for the development of efficient drugs against AD.  相似文献   
32.
Mammalian cloning by nuclear transfer from somatic cells has created new opportunities to generate animal models of genetic diseases in species other than mice. Although genetic mouse models play a critical role in basic and applied research for numerous diseases, often mouse models do not adequately reproduce the human disease phenotype. Cystic fibrosis (CF) is one such disease. Targeted ablation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in mice does not adequately replicate spontaneous bacterial infections observed in the human CF lung. Hence, several laboratories are pursuing alternative animal models of CF in larger species such as the pig, sheep, rabbits, and ferrets. Our laboratory has focused on developing the ferret as a CF animal model. Over the past few years, we have investigated several experimental parameters required for gene targeting and nuclear transfer (NT) cloning in the ferret using somatic cells. In this review, we will discuss our progress and the hurdles to NT cloning and gene-targeting that accompany efforts to generate animal models of genetic diseases in species such as the ferret.  相似文献   
33.
刘紫怡  胡文涛  陈辉  唐明 《菌物学报》2022,41(7):1123-1133
彩色豆马勃Pisolithus tinctorius可广泛与林木建立外生菌根,其共生可促进植物生长,提高植物对重金属的耐受性。然而,关于彩色豆马勃对重金属锌(Zn)胁迫的生理响应还不完全清楚。本研究在纯培养条件下,测定了Zn胁迫对彩色豆马勃生物量、Zn的活性形态和亚细胞分布,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性,谷胱甘肽(GSH)、抗坏血酸(AsA)和黑色素含量的影响。结果表明,Zn胁迫抑制了彩色豆马勃的生长,在浓度为563 μmol/L时,达到半数最大抑制浓度(IC50),在浓度为600 μmol/L时,生物量降低42.6%。Zn在彩色豆马勃中以活性较低的草酸盐、难溶于水的磷酸盐、果胶酸盐以及与蛋白质呈结合态或吸着态的形式为主。Zn胁迫显著提高了彩色豆马勃菌丝中CAT、POD和SOD活性,增加了GSH和黑色素含量,但对AsA的含量没有显著影响。本研究表明,彩色豆马勃主要通过调节Zn的分布及抗氧化系统,增加黑色素含量,增强对Zn的耐受性,为外生菌根真菌修复重金属污染土壤提供了理论支持。  相似文献   
34.
Cloning mammals by nuclear transfer is a powerful technique that is quickly advancing the development of genetically defined animal models. However, the overall efficiency of nuclear transfer is still very low and several hurdles remain before the power of this technique will be fully harnessed. Among these hurdles include an incomplete understanding of biologic processes that control epigenetic reprogramming of the donor genome following nuclear transfer. Incomplete epigenetic reprogramming is considered the major cause of the developmental failure of cloned embryos and is frequently associated with the disregulation of specific genes. At present, little is known about the developmental mechanism of reconstructed embryos. Therefore, screening strategies to design nuclear transfer protocols that will mimic the epigenetic remodeling occurring in normal embryos and identifying molecular parameters that can assess the developmental potential of pre-implantation embryos are becoming increasingly important. A crucial need at present is to understand the molecular events required for efficient reprogramming of donor genomes after nuclear transfer. This knowledge will help to identify the molecular basis of developmental defects seen in cloned embryos and provide methods for circumventing such problems associated with cloning the future application of this technology.  相似文献   
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36.
Functional human hepatocytes are one of the most significant tools for studying drug absorption, distribution, metabolism and excretion/toxicity (ADME/Tox), especially for applications in preclinical drug development (Sahi et al., 2010; Godoy et al., 2013). They provide the closest in vitro model to the human liver and the only model that mimics the drug metabolic profiles found in vivo. However, these cells lose their metabolic function rapidly and dramatically during the in vitro culture process, which largely hinders their wider application in drug development (Sahi et al., 2010; Godoy et al., 2013). To overcome this obstacle, it is important to regulate the activities of key genes which are responsible for the detoxification metabolic function of human hepatocytes.  相似文献   
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38.
Danthron is an important natural occurring component in laxative drugs. In this paper, electrochemical investigation of danthron and its interaction with DNA is reported. Via the electrochemical approach assisted by ultraviolet-visible (UV-Vis) spectroscopy, we have proved that danthron intercalates into DNA strands forming some nonelectroactive complexes, which results in the decrease of redox peak currents of danthron. In addition, the decrease of the peak currents is proportional to the concentration of DNA. The difference between the interaction of danthron with double-stranded DNA (dsDNA) and with single-stranded DNA (ssDNA) has also been studied. This character implies the potential of danthron to discriminate dsDNA and ssDNA.  相似文献   
39.
Aqueous rechargeable zinc ion batteries are considered a promising candidate for large‐scale energy storage owing to their low cost and high safety nature. A composite material comprised of H2V3O8 nanowires (NWs) wrapped by graphene sheets and used as the cathode material for aqueous rechargeable zinc ion batteries is developed. Owing to the synergistic merits of desirable structural features of H2V3O8 NWs and high conductivity of the graphene network, the H2V3O8 NW/graphene composite exhibits superior zinc ion storage performance including high capacity of 394 mA h g?1 at 1/3 C, high rate capability of 270 mA h g?1 at 20 C and excellent cycling stability of up to 2000 cycles with a capacity retention of 87%. The battery offers a high energy density of 168 W h kg?1 at 1/3 C and a high power density of 2215 W kg?1 at 20 C (calculated based on the total weight of H2V3O8 NW/graphene composite and the theoretically required amount of Zn). Systematic structural and elemental characterization confirm the reversible Zn2+ and water cointercalation electrochemical reaction mechanism. This work brings a new prospect of designing high‐performance aqueous rechargeable zinc ion batteries for grid‐scale energy storage.  相似文献   
40.
Actin motor myosin proteins are the driving forces behind the active transport of vesicles, and more than 20 classes of myosin have been found to contribute to a wide range of cellular processes, including endocytosis and exocytosis, autophagy, cytokinesis and the actin cytoskeleton. In Saccharomyces cerevisiae, class V myosin Myo2 (ScMyo2p) is important for the transport of distinct sets of cargo to regions of the cell along the cytoskeleton for polarized growth. To study whether myosins play a role in the formation or function of the appressorium (infectious structure) of the rice blast fungus Magnaporthe oryzae, we identified MoMyo5 as an orthologue of ScMyo2p and characterized its function. Targeted gene disruption revealed that MoMyo5 is required for intracellular transport and is essential for hyphal growth and asexual reproduction. Although the ΔMomyo5 mutant could form appressorium‐like structures, the structures were unable to penetrate host cells and were therefore non‐pathogenic. We further found that MoMyo5 moves dynamically from the cytoplasm to the hyphal tip, where it interacts with MoSec4, a Rab GTPase involved in secretory transport, hyphal growth and fungal pathogenicity. Our studies indicate that class V myosin and its translocation are tightly coupled with hyphal growth, asexual reproduction, appressorium function and pathogenicity in the rice blast fungus.  相似文献   
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