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101.
We investigated the role of some key regulators of cell cycle in the activation of caspases during apoptosis of insulin-secreting cells after sustained depletion of GTP by a specific inosine 5'-monophosphate dehydrogenase inhibitor, mycophenolic acid (MPA). p21(Waf1/Cip1) was significantly increased following MPA treatment, an event closely correlated with the time course of caspase activation under the same conditions. MPA-induced p21(Waf1/Cip1) was not mediated by p53, since p53 mass was gradually reduced over time of MPA treatment. The increment of p21(Waf1/Cip1) by MPA was further enhanced in the presence of a pan-caspase inhibitor, indicating that the increased p21(Waf1/Cip1) may occur prior to caspase activation. This notion of association of p21(Waf1/Cip1) accumulation with caspase activation and apoptosis was substantiated by using mimosine, a selective p21(Waf1/Cip1) inducer independent of p53. Mimosine, like MPA, also increased p21(Waf1/Cip1), promoted apoptosis and simultaneously increased the activity of caspases. Furthermore, knocking down of p21(Waf1/Cip1) transfection of siRNA duplex inhibited caspase activation and apoptosis due to GTP depletion. In contrast to p21(Waf1/Cip1), a reduction in p27(Kip1) occurred in MPA-treated cells. These results indicate that p21(Waf1/Cip1) may act as an upstream signal to block mitogenesis and activate caspases which in turn contribute to induction of apoptosis. 相似文献
102.
Hanyu Huo Yue Chen Jing Luo Xiaofei Yang Xiangxin Guo Xueliang Sun 《Liver Transplantation》2019,9(17)
Solid polymer electrolytes as one of the promising solid‐state electrolytes have received extensive attention due to their excellent flexibility. However, the issues of lithium (Li) dendrite growth still hinder their practical applications in solid‐state batteries (SSBs). Herein, composite electrolytes from “ceramic‐in‐polymer” (CIP) to “polymer‐in‐ceramic” (PIC) with different sizes of garnet particles are investigated for their effectiveness in dendrite suppression. While the CIP electrolyte with 20 vol% 200 nm Li6.4La3Zr1.4Ta0.6O12 (LLZTO) particles (CIP‐200 nm) exhibits the highest ionic conductivity of 1.6 × 10?4 S cm?1 at 30 °C and excellent flexibility, the PIC electrolyte with 80 vol% 5 µm LLZTO (PIC‐5 µm) shows the highest tensile strength of 12.7 MPa. A sandwich‐type composite electrolyte (SCE) with hierarchical garnet particles (a PIC‐5 µm interlayer sandwiched between two CIP‐200 nm thin layers) is constructed to simultaneously achieve dendrite suppression and excellent interfacial contact with Li metal. The SCE enables highly stable Li plating/stripping cycling for over 400 h at 0.2 mA cm?2 at 30 °C. The LiFePO4/SCE/Li cells also demonstrate excellent cycle performance at room temperature. Fabricating sandwich‐type composite electrolytes with hierarchical filler designs can be an effective strategy to achieve dendrite‐free SSBs with high performance and high safety at room temperature. 相似文献
103.
Graft-versus-host disease (GVHD) induced by host antigen-presenting cells (APCs) and donor-derived T cells remains the major limitation of allogeneic bone marrow transplantation (allo-BMT). Notch signaling pathway is a highly conserved cell-cell communication that is important in T cell development. Recently, Notch signaling pathway is reported to be involved in regulating GVHD. To investigate the role of Notch inhibition in modulating GVHD, we established MHC-mismatched murine allo-BMT model. We found that inhibition of Notch signaling pathway by γ-secretase inhibitor in vivo could reduce aGVHD, which was shown by the onset time of aGVHD, body weight, clinical aGVHD scores, pathology aGVHD scores, and survival. Inhibition of Notch signaling pathway by DAPT ex vivo only reduced pathology aGVHD scores in the liver and intestine and had no impact on the onset time and clinical aGVHD scores. We investigated the possible mechanism by analyzing the phenotype of host APCs and donor-derived T cells. Notch signaling pathway had a broad effect on both host APCs and donor-derived T cells. The expressions of CD11c, CD40, and CD86 as the markers of activated dendritic cells (DCs) were decreased. The proliferative response of CD8+ T cell decreased, while CD4+ Notch-deprived T cells had preserved expansion with increased expressions of CD25 and Foxp3 as markers of regulatory T cells (Tregs). In conclusion, Notch inhibition may minimize aGVHD by decreasing proliferation and activation of DCs and CD8+ T cells while preserving Tregs expansion. 相似文献
104.
Association between the change in body mass index from early adulthood to midlife and subsequent type 2 diabetes mellitus 下载免费PDF全文
Yiming Mu Chao Liu Jiajun Zhao Lulu Chen Qiang Li Tao Yang Li Yan Qin Wan Shengli Wu Yan Liu Guixia Wang Zuojie Luo Xulei Tang Gang Chen Yanan Huo Zhengnan Gao Qing Su Youmin Wang Guijun Qin Huacong Deng Xuefeng Yu Feixia Shen Li Chen Liebin Zhao Jichao Sun Lin Ding Yu Xu Min Xu Meng Dai Tiange Wang Di Zhang Jieli Lu Yufang Bi Shenghan Lai Donghui Li Weiqing Wang Guang Ning 《Obesity (Silver Spring, Md.)》2016,24(3):703-709
105.
Human isolated gingival fibromatosis is an oral disorder characterized by a slowly progressive benign enlargement of gingival
tissues. The most common genetic form, hereditary gingival fibromatosis (HGF), is usually transmitted as an autosomal dominant
trait. We report here for the first time a newly identified maternally inherited gingival fibromatosis in two unrelated Chinese
families and mapped this disease locus to human chromosome 11p15 with a maximum two point LOD score of 8.70 at D11S4046 (θ = 0) for family 1 and of 6.02 at D11S1318 for family 2. Haplotype analysis placed the critical region in the interval defined by D11S1984 and D11S1338. A cluster of maternally expressed genes is within this critical region. We screened individuals in these two families for
mutations for all known maternally expressed genes within this region. None was found either within the coding sequence or
at the intron–exon boundary of these genes. Neither did we detect any loss of imprinting in three informative imprinted genes
including H19, KCNQ1 downstream neighbor (KCNQ1DN) and cyclin-dependent kinase inhibitor 1C (CDKN1C). However, gene expression profile analysis revealed reduced expression of hemoglobin beta (HBB), hemoglobin delta (HBD), hemoglobin gamma A (HBG1) and hemoglobin gamma G (HBG2) genes at disease locus in HGF patients. This study suggests that genome imprinting might affect the development of HGF.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.
Conflict Of Interest Statement: No competing financial interests. 相似文献
106.
Yong Liang De-Yun Zhang Shuhong Ouyang Jingzhong Xie Qiuhong Wu Zhenzhong Wang Yu Cui Ping Lu Dong Zhang Zi-Ji Liu Jie Zhu Yong-Xing Chen Yan Zhang Ming-Cheng Luo Jan Dvorak Naxin Huo Qixin Sun Yong-Qiang Gu Zhiyong Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2015,128(8):1617-1629
107.
108.
Shijie He Chenglin Liu Xiaojun Li Shaopeng Ma Bo Huo Baohua Ji 《Biophysical journal》2015,108(3):489-497
Mechanical properties of cell membranes are known to be significantly influenced by the underlying cortical cytoskeleton. The technique of pulling membrane tethers from cells is one of the most effective ways of studying the membrane mechanics and the membrane-cortex interaction. In this article, we show that axon membranes make an interesting system to explore as they exhibit both free membrane-like behavior where the tether-membrane junction is movable on the surface of the axons (unlike many other cell membranes) as well as cell-like behavior where there are transient and spontaneous eruptions in the tether force that vanish when F-actin is depolymerized. We analyze the passive and spontaneous responses of axonal membrane tethers and propose theoretical models to explain the observed behavior. 相似文献
109.
Jianfeng Li Shuqing Zhang Shangli Shi Pinghui Huo 《World journal of microbiology & biotechnology》2011,27(6):1481-1489
Nitrogen (N) fixing Klebsiella pneumoniae RSN19 has high inorganic phosphorus (P) solubilizing capability, but its N2-fixing capability is limited. In order to acquire a P-solubilizing mutant strain with high efficiency N-fixing capability,
different microwave irradiation intensities and durations were tested on RSN19 in an attempt to produce mutants with improved
N2-fixation and P-solubilization capabilities. The effect of microwave irradiation power and time were studied and the microwave
mutagenesis parameters were optimized. Nitrogenase activity was tested on the mutant strains by acetylene reduction method;
and their P-solubilizing capability and genetic stability were determined. The results indicated that the best conditions
for microwave mutagenesis that produced better performed mutant strains were 250W, 36 s. Under these conditions a maximum
positive mutation rate of 1.66% was obtained, resulting in five genetically stable strains with promoted nitrogenase activity
which was designated as RSM-219, RSM-206, RSM-224, RSM-225 and RSM-275. Subculture tests showed that RSM-219 and RSM-206 were
genetically stable mutant strains with higher nitrogenase activity and phosphate solubilizing capabilities than the original
strain. Both RSM-219 and RSM-206 performed better than the original strain under N-free conditions when supplied with calcium
phosphate only, and produced greater increases in the biomass of alfalfa seedlings. 相似文献
110.