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81.
Mitochondrial dysfunction in platelets and hippocampi of senescence-accelerated mice 总被引:5,自引:0,他引:5
Xu J Shi C Li Q Wu J Forster EL Yew DT 《Journal of bioenergetics and biomembranes》2007,39(2):195-202
Senescence-accelerated mice (SAM) strains are useful models to understand the mechanisms of age-dependent degeneration. In
this study, measurements of the mitochondrial membrane potential (Δψm) of platelets and the Adenosine 5′-triphosphate (ATP) content of hippocampi and platelets were made, and platelet mitochondria were observed in SAMP8 (faster
aging mice) and SAMR1 (aging resistant control mice) at 2, 6 and 9 months of age. In addition, an Aβ-induced (Amyloid beta-protein)
damage model of platelets was established. After the addition of Aβ, the Δψm of platelets of SAMP8 at 1and 6 months of age were measured. We found that platelet Δψm, and hippocampal and platelet ATP content of SAMP8 mice decreased at a relatively early age compared with SAMR1. The platelets
of 6 month-old SAMP8 showed a tolerance to Aβ-induced damages. These results suggest that mitochondrial dysfunction might
be one of the mechanisms leading to age-associated degeneration in SAMP mice at an early age and the platelets could serve
as a biomarker for detection of mitochondrial function and age related disease. 相似文献
82.
Frequent amplification and abundant expression of Nkd2 has been identified in malignant peripheral nerve sheath tumors (MPNSTs), dominant for genomic instability, who is involved in both Wnt pathway and EGFR signaling pathway. As a negative regulator of Wnt pathway, Nkd2 suppresses Wnt signaling by binding to Dvl1 and causing its ubiquitination followed by 26S proteasome degradation. On the other hand, it interacts with TGF-α for its transportation to basolateral plasma membrane in polarized epithelial cells. It is of interest to determine if Nkd2 over-expression contributes to tumorigenesis and genomic instablity. In this paper, we found that cells expressing NKD2 delayed mitotic exit stage after double thymidine block synchronization, but aneuploidy was not detected in these cells. This was further confirmed by Western blotting. In nocodazole-synchronised cells, Cyclin B1 degradation was delayed with Nkd2 over-expression compared to control group. Given many previous publications showed that Wnt pathway components are involved in mitotic progression. Further investigation on Nkd2’s function in mitosis might give more clues on MPNSTs pathological progression. 相似文献
83.
Yao Shi Juan Yuan Vilma Rraklli Eva Maxymovitz Miriam Cipullo Mingzhi Liu Shuijie Li Isabelle Westerlund Oscar C Bedoya-Reina Petra Bullova Joanna Rorbach C Christofer Juhlin Adam Stenman Catharina Larsson Per Kogner Maureen J OSullivan Susanne Schlisio Johan Holmberg 《Nucleic acids research》2021,49(5):2509
84.
Xiangbin Xu Jufang Bian Songbai Liu Hongmiao Song Nongnong Shi Yuezhi Tao Huizhong Wang 《Molecular breeding : new strategies in plant improvement》2011,27(3):337-346
The PROMOTION OF CELL SURVIVAL 1 (PCS1) gene, encoding an aspartic protease, has an important role in determining the fate of cells in embryonic development and
reproduction processes in Arabidopsis. To explore the potential function of the PCS1 gene in generating reproductive sterility, we placed the PCS1 gene under the control of an 1,869-bp nucleotide sequence from the 3′ end of the second intron (AG-I) of Arabidopsis AGAMOUS and CaMV 35S (–60) minimal promoter [AG-I-35S (–60)::PCS1], and introduced it into tobacco. RT–PCR results demonstrated that the PCS1 gene driven by AG-I-35S (–60) chimeric promoter was expressed only in anthers and carpels in the reproductive tissues of transgenic tobacco. Compared to
wild-type plants, all AG-I-35S (–60) and AG-I-35S (–60)::PCS1 transgenic lines showed a normal phenotype throughout the vegetative growth phase. However, during the reproductive stage,
most AG-I-35S (–60)::PCS1 transgenic plant anthers displayed delayed dehiscence, failed dehiscence, petalody and hypoplasia, and the pollen grains
had different shapes and sizes with a distorted, shrunken, or collapsed morphology. Moreover, three transgenic lines, PCS1-1,
PCS1-3 and PCS1-4, showed higher sterility than wild-type and AG-I-35S (–60) transgenic plants, respectively. These results showed that the construct of AG-I-35S (–60)::PCS1 was partially effective at preventing seed set and provided a novel sterility strategy. 相似文献
85.
Shi Yu Mao Xudong Cai Mingcheng Hu Shenqiang Lai Xiulan Chen Shiyi Jia Xianbo Wang Jie Lai Songjia 《Molecular and cellular biochemistry》2021,476(1):425-433
Molecular and Cellular Biochemistry - Skeletal muscle satellite cells (SMSCs), also known as a multipotential stem cell population, play a crucial role during muscle growth and regeneration. In... 相似文献
86.
87.
Ming Li Luca Vanella Yuming Zhang Ming Shi Takashi Takaki Joseph I Shapiro Susumu Ikehara 《International journal of biological sciences》2012,8(10):1335-1344
Intra bone marrow-bone marrow transplantation (IBM- BMT) + thymus transplantation (TT) has been shown to reduce the incidence of graft versus host disease (GVHD) and restore donor-derived T cell function. In addition, an increase in insulin sensitivity occurred in db/db mice after IBM-BMT+TT treatment. Heme oxygenase (HO)-1 is a stress inducible enzyme which exert antioxidant, antiapoptotic, and immune-modulating properties. We examined whether IBM-BMT+TT could modulate the expression of HO-1 in the kidneys of db/db mice. Six-week-old db/db mice with blood glucose levels higher than 250 mg/dl were treated with IBM-BMT+TT. Six weeks later, the db/db mice showed decreased body weight, blood glucose levels and insulin, and increased plasma adiponectin levels. The upregulation of HO-1 was associated with significantly (p<0.05) increased levels of peNOS and pAKT, but decreased levels of iNOS in the kidneys of db/db mice. Plasma creatinine levels also decreased (p<0.05), and the expression of type IV collagen was improved. Thus IBM-BMT+TT unregulated the expression of HO-1, peNOS and pAKT, while decreasing iNOS levels in the kidney of db/db mice. This was associated with an improvement in renal function. 相似文献
88.
表观遗传学对于微生物的生命进程起着重要作用。由限制-修饰系统调控的DNA修饰参与微生物的免疫防御系统,无限制-修饰系统调控的DNA修饰通过调控基因表达影响表型。然而,表观遗传信息还没有被常规地作为DNA信息收集分析。基于对DNA合成反应的动力学分析,单分子实时测序技术可以在获得基本序列数据的同时实现对被修饰核苷酸的检测。这个技术为微生物中已知DNA修饰的研究提供了新的平台,也为新型DNA修饰的发现做好准备。本文综述了单分子实时测序技术及其在微生物表观遗传学中的应用。 相似文献
89.
Burmite (Burmese amber) from the Hukawng Valley in northern Myanmar is a remarkable valuable and obviously the most important amber for studying terrestrial diversity in the mid-Cretaceous.The diversity of Burmite inclusions is very high and many new taxa were found,including new order,new family/subfamily,and new genus.Till the end of 2016,14 phyla,21 classes,65 orders,279 families,515 genera and 643 species of organisms are recorded,which are summized and complied in this catalogue.Among them,587 species are arthropods.In addtion,the specimens which can not be identified into species are also listed in the paper.The information on type specimens,other materials,host and deposition of types are provided. 相似文献
90.
Shi Yang Li Wei Yu Yao Yong Jin Yuan Wen Shu Tay Nian-Lin Reena Han Rehena Sultana Pryseley N. Assam Alex Tiong-Heng Sia Ban Leong Sng 《BMC anesthesiology》2017,17(1):169