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21.
Although cisplatin is one of the chemotherapeutics most frequently used in oral squamous cell carcinoma (OSCC) treatment,it exerts multiple side effects and poo...  相似文献   
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The mortality of patients with malignant gliomas remains high despite the advancement in multi-modal therapy including surgery, radio- and chemotherapy. Glioma stem cells (GSCs), sharing some characteristics with normal neural stem cells (NSCs), contribute to the cellular origin for primary gliomas and the recurrence of malignant gliomas after current conventional therapy. Accordingly, targeting GSCs proves to be a promising avenue of therapeutic intervention. The specific tropism of NSCs to GSCs provides a novel platform for targeted delivery of therapeutic agents. Tropism and mobilization of NSCs are enhanced by hypoxia through upregulating chemotactic cytokines and activating several signaling pathways. Moreover, hypoxia-inducible factors (HIFs) produced under hypoxic microenvironment of the stem cell niche play critical roles in the growth and stemness phenotypes regulation of both NSCs and GSCs. However, the definite cellular and molecular mechanisms of HIFs involvement in the process remain obscure. In this review, we focus on the pivotal roles of HIFs in migration of NSCs to GSCs and potential roles of HIFs in dictating the fates of migrated NSCs and targeted GSCs.  相似文献   
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It has been reported that buffalo (Bubalus bubalis) embryos reconstructed by somatic cell nucleus transfer (SCNT) can develop to the full term of gestation and result in newborn calves. However, the developmental competence of reconstructed embryos is still low. Recently, it has been reported that treating donor cells or embryos with trichostatin A (TSA) can increase the cloning efficiency in some species. Thus, the present study was undertaken to improve the development of buffalo SCNT embryos by treatment of donor cells (buffalo fetal fibroblasts) with TSA and explore the relation between histone acetylation status of donor cells and developmental competence of SCNT embryos. Treatment of donor cells with either 0.15 or 0.3 μM TSA for 48 hours resulted in a significant increase in the cleavage rate and blastocyst yield of SCNT embryos (P < 0.05). Meanwhile, the expression level of HDAC1 in donor cells was also decreased (0.4–0.6 fold, P < 0.05) by TSA treatment, although the expression level of HAT1 was not affected. Further measurement of the epigenetic maker AcH4K8 in buffalo IVF and SCNT embryos at the eight-cell stage revealed that the spatial distribution of acH4K8 staining in SCNT embryos was different from the IVF embryos. Treatment of donor cells with TSA resulted in an increase in the AcH4K8 level of SCNT embryos and similar to fertilized counterparts. These results suggest that treatment of donor cells with TSA can facilitate their nucleus reprogramming by affecting the acetylated status of H4K8 and improving the in vitro development of buffalo SCNT embryos. The AcH4K8 status at the eight-cell stage can be used as an epigenetic marker for predicting the SCNT efficiency in buffalos.  相似文献   
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Yang CH  Liu XM  Si JJ  Shi HS  Xue YX  Liu JF  Luo YX  Chen C  Li P  Yang JL  Wu P  Lu L 《PloS one》2012,7(6):e39696
The inhibitor κB protein kinase/nuclear factor κB (IKK/NF-κB) signaling pathway is critical for synaptic plasticity. However, the role of IKK/NF-κB in drug withdrawal-associated conditioned place aversion (CPA) memory is unknown. Here, we showed that inhibition of IKK/NF-κB by sulphasalazine (SSZ; 10 mM, i.c.v.) selectively blocked the extinction but not acquisition or expression of morphine-induced CPA in rats. The blockade of CPA extinction induced by SSZ was abolished by sodium butyrate, an inhibitor of histone deacetylase. Thus, the IKK/NF-κB signaling pathway might play a critical role in the extinction of morphine-induced CPA in rats and might be a potential pharmacotherapy target for opiate addiction.  相似文献   
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Achieving high-performance in all-small-molecule organic solar cells (ASM-OSCs) significantly relies on precise nanoscale phase separation through domain size manipulation in the active layer. Nonetheless, for ASM-OSC systems, forging a clear connection between the tuning of domain size and the intricacies of phase separation proves to be a formidable challenge. This study investigates the intricate interplay between domain size adjustment and the creation of optimal phase separation morphology, crucial for ASM-OSCs’ performance. It is demonstrated that exceptional phase separation in ASM-OSCs’ active layer is achieved by meticulously controlling the continuity and uniformity of domains via re-packing process. A series of halogen-substituted solvents (Fluorobenzene, Chlorobenzene, Bromobenzene, and Iodobenzene) is adopted to tune the re-packing kinetics, the ASM-OSCs treated with CB exhibited an impressive 16.2% power conversion efficiency (PCE). The PCE enhancement can be attributed to the gradual crystallization process, promoting a smoothly interconnected and uniformly distributed domain size. This, in turn, leads to a favorable phase separation morphology, enhanced charge transfer, extended carrier lifetime, and consequently, reduced recombination of free charges. The findings emphasize the pivotal role of re-packing kinetics in achieving optimal phase separation in ASM-OSCs, offering valuable insights for designing high-performance ASM-OSCs fabrication strategies.  相似文献   
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本文介绍一种目视激光显微镜。该装置采用白炽灯和激光做光源。通过调压器衬底亮度可以调整到零。由于激光的高亮度和强相干性,与普通显微镜相比,该显微镜具有景深长,分辨率高,层次丰富的特点。使用该显微镜时能实现镜象的假色彩编码,且镜象具有立体感。文中报导了该显微镜的原理和使用效果。  相似文献   
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