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81.
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   
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84.
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   
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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.

Background

The Supreme? laryngeal mask airway (SLMA) is a single-use LMA with double lumen design that allows separation of the respiratory and the alimentary tract, hence potentially reducing the gastric volume and risk of aspiration. The purpose of this prospective cohort study is to evaluate the the role of the SLMA as an airway technique for women undergoing category 2 and 3 Cesarean delivery under general anesthesia.

Methods

We recruited 584 parturients who underwent category 2 or 3 Cesarean delivery under general anesthesia, in which 193 parturients underwent category 2 and 391 parturients underwent category 3 Cesarean delivery. The primary outcome was insertion success rate at 1st attempt in SLMA insertion. The secondary outcomes included anaesthetic, obstetric outcomes and maternal side effects associated with airway device.

Results

The 1st attempt insertion success rate was 98.3%, while the overall insertion success rate was 100%. The mean (Standard deviation) time to effective ventilation was 15.6 (4.4) seconds. Orogastric tube insertion was successful at the 1st attempt in all parturients. There was no clinical evidence of aspiration or regurgitation. No episodes of hypoxemia, laryngospasm or bronchospasm were observed intra-operatively. The incidence of complications was low and with good maternal satisfaction reported.

Conclusions

The SLMA could be an alternative effective airway in category 2 and 3 parturients emergency Cesarean Delivery under general anesthesia in a carefully-selected obstetric population.

Trial registration

Clinical Trials Registration: Clinicaltrials.gov Registration NCT02026882. Registered on December 31, 2013.
  相似文献   
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