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971.
Liang Meng Ying Zhu Ning Zhang Wanjun Liu Yang Liu Changwei Shao Na Wang Songlin Chen 《PloS one》2014,9(10)
Testis-specific protein kinase 1 (Tesk1) is a serine/threonine kinase with unique structural features. In the present study, we cloned and characterized the tesk1 gene of tongue sole, Cynoglossus semilaevis. The full-length tesk1 cDNA consists of 1,672 nucleotides, encoding a 331 amino acid polypeptide with a characteristic structure composed of an N-terminal kinase domain and a C-terminal proline-rich domain. The tesk1 genomic sequence contains eight exons and seven introns. Real-time quantitative PCR revealed that tesk1 mRNA is expressed predominantly in the testis, though the level of expression varied throughout development. We used in situ hybridization to show that tesk1 mRNA is expressed in the spermatids of males and pseudo-males, but not in triploid males. Our results suggest that tongue sole Tesk1 may play a role in spermatogenesis. 相似文献
972.
Shenglin Chen Cunhua Shao Tianfu Dong Hao Chai Xinkui Xiong Daoyi Sun Long Zhang Yue Yu Ping Wang Feng Cheng 《PloS one》2014,9(11)
Background
Recent studies have demonstrated that transplantation of ATP7B-transduced hepatocytes ameliorates disease progression in LEC (Long-Evans Cinnamon) rats, a model of Wilson''s disease (WD). However, the inability of transplanted cells to proliferate in a normal liver hampers long-term treatment. In the current study, we investigated whether transplantation of ATP7B-transduced bone marrow mesenchymal stem cells (BM-MSCs) could decrease copper overload in LEC rats.Materials and Methods
The livers of LEC rats were preconditioned with radiation (RT) and/or ischemia-reperfusion (IRP) before portal vein infusion of ATP7B-transduced MSCs (MSCsATP7B). The volumes of MSCsATP7B or saline injected as controls were identical. The expression of ATP7B was analyzed by real-time quantitative polymerase chain reaction (RT-PCR) at 4, 12 and 24 weeks post-transplantation. MSCATP7B repopulation, liver copper concentrations, serum ceruloplasmin levels, and alanine transaminase (ALT) and aspartate transaminase (AST) levels were also analyzed at each time-point post-transplantation.Results
IRP-plus-RT preconditioning was the most effective strategy for enhancing the engraftment and repopulation of transplanted MSCsATP7B. This strategy resulted in higher ATP7B expression and serum ceruloplasmin, and lower copper concentration in this doubly preconditioned group compared with the saline control group, the IRP group, and the RT group at all three time-points post-transplantation (p<0.05 for all). Moreover, 24 weeks post-transplantation, the levels of ALT and AST in the IRP group, the RT group, and the IRP-plus-RT group were all significantly decreased compared to those of the saline group (p<0.05 compared with the IRP group and RT group, p<0.01 compared with IRP-plus-RT group); ALT and AST levels were significantly lower in the IRP-plus-RT group compared to either the IRP group or the RT group (p<0.01 and p<0.05. respectively).Conclusions
These results demonstrate that transplantation of MSCsATP7B into IRP-plus-RT preconditioned LEC rats decreased copper overload and was associated with an increase in MSC engraftment and repopulation. 相似文献973.
Inferring new indication of approved drugs is critical not only for the elucidation of the interaction mechanisms between these drugs and their associated diseases, but also for the development of drug therapy for various human diseases. This paper proposes a network-based approach to reveal the association between 52 human diseases and potential therapeutic drugs based on multiple types of data. The advantage of the approach is that it can obtain the global relevance features for each drug-disease pair in the network by the learning local and global consistency method (LLGC). Cross-validation tests results demonstrate the proposed approach can achieve better performance comparing with previous methods. More importantly, it provides a promising strategy to maximize the value of therapeutic drugs and offer safe and effective treatments for different diseases. 相似文献
974.
医疗设备采购工作由于环节众多,过程复杂,且工作性质的特殊性、敏感性关系,很多的审批、监督环节无法省略,对工作速度造成了严重影响。该文探讨了一种基于项目团队模式的医疗设备采购管理新模式。打破了采购工作各相关部门的职能壁垒,按精细化管理的原则,构建了一个跨部门的医疗设备采购工作职能团队,快速、准确、高效地完成大型医院医疗设备购置工作,提高医疗设备采购工作的效率和质量,以充分发掘采购工作的效益。 相似文献
975.
Polycystic ovary syndrome (PCOS) is a state of altered steroid hormone production and activity. Chronic estrogen exposure or lack of progesterone due to ovarian dysfunction can result in endometrial hyperplasia and carcinoma. A key contributor to our understanding of progesterone as a critical regulator for normal uterine function has been the elucidation of progesterone receptor (PR) expression, regulation, and signaling pathways. Several human studies indicate that PR-mediated signaling pathways in the nucleus are associated with progesterone resistance in women with PCOS. The aim of this review is to provide an overview of endometrial progesterone resistance in women with PCOS; to present the PR structure, its different isoforms, and their expression in the endometrium; to illustrate the possible regulation of PR and PR-mediated signaling in progesterone resistance in women with PCOS; and to discuss current clinical treatments for atypical endometrial hyperplasia and endometrial carcinoma in women with PCOS and accompanying progesterone resistance. 相似文献
976.
977.
978.
Yu-Jie Wu Zhi-Yi Fu Xiao-Peng Hu Jiang Shao Xing-Zhen Liu Wen-Jie Jin 《Cell biochemistry and biophysics》2014,69(1):75-80
We prospectively studied the effectiveness of the repositioning suture of the erector spinae muscle for lumbar spine surgery using the posterior approach. 393 patients undergoing lumbar spine surgery were randomized to receive the repositioning or conventional suture of the erector spinae muscle. Time to stitch removal and drainage volume was recorded at 24 and 48 h after operation. Hemoglobin loss rate was determined at 48 h post operation and the rate of malunion (redness, swelling and effusion at stitch removal and would disruption after stitch removal) was recorded. Low back pain was evaluated using the visual analog scale (VAS) preoperatively and 6 and 12 months after operation. Time to stitch removal was comparable in lumbar spine surgery patients receiving the repositioning or conventional suture of the erector spinae muscle (P > 0.05). Compared with the conventional suture, the repositioning suture was associated with significantly reduced drainage volume both at 24 (P < 0.01) and 48 h after operation (P < 0.05). Hemoglobin loss rate at 48 h post operation was also markedly lower in lumbar spine surgery patients receiving the repositioning suture than in those receiving the conventional suture (P < 0.01 or 0.05). Furthermore, the malunion rate in lumbar spine surgery patients using the repositioning suture was markedly lower than that in the conventional group (P < 0.05 or 0.001). There was no difference in preoperative VAS scores in both the groups (P > 0.05). Compared with the conventional suture, the repositioning suture was associated with significantly reduced VAS scores both at 24 and 48 h after operation (P < 0.01 in both). The repositioning suture of the erector spinae muscle is superior to the conventional suture in posterior lumbar spine surgery with marked lessened pain and reduced drainage volume. 相似文献
979.
X-N Wu Z-H Yang X-K Wang Y Zhang H Wan Y Song X Chen J Shao J Han 《Cell death and differentiation》2014,21(11):1709-1720
Necroptosis is mediated by a signaling complex called necrosome, containing receptor-interacting protein (RIP)1, RIP3, and mixed-lineage kinase domain-like (MLKL). It is known that RIP1 and RIP3 form heterodimeric filamentous scaffold in necrosomes through their RIP homotypic interaction motif (RHIM) domain-mediated oligomerization, but the signaling events based on this scaffold has not been fully addressed. By using inducible dimer systems we found that RIP1–RIP1 interaction is dispensable for necroptosis; RIP1–RIP3 interaction is required for necroptosis signaling, but there is no necroptosis if no additional RIP3 protein is recruited to the RIP1–RIP3 heterodimer, and the interaction with RIP1 promotes the RIP3 to recruit other RIP3; RIP3–RIP3 interaction is required for necroptosis and RIP3–RIP3 dimerization is sufficient to induce necroptosis; and RIP3 dimer-induced necroptosis requires MLKL. We further show that RIP3 oligomer is not more potent than RIP3 dimer in triggering necroptosis, suggesting that RIP3 homo-interaction in the complex, rather than whether RIP3 has formed homo polymer, is important for necroptosis. RIP3 dimerization leads to RIP3 intramolecule autophosphorylation, which is required for the recruitment of MLKL. Interestingly, phosphorylation of one of RIP3 in the dimer is sufficient to induce necroptosis. As RIP1–RIP3 heterodimer itself cannot induce necroptosis, the RIP1–RIP3 heterodimeric amyloid fibril is unlikely to directly propagate necroptosis. We propose that the signaling events after the RIP1–RIP3 amyloid complex assembly are the recruitment of free RIP3 by the RIP3 in the amyloid scaffold followed by autophosphorylation of RIP3 and subsequent recruitment of MLKL by RIP3 to execute necroptosis.Necroptosis is a type of programmed necrosis characterized by necrotic morphological changes, including cellular organelle swelling, cell membrane rupture,1, 2, 3 and dependence of receptor-interacting protein (RIP)14 and RIP3.5, 6, 7 Physiological function of necroptosis has been illustrated in host defense,8, 9, 10, 11 inflammation,12, 13, 14, 15, 16 tissue injury,10, 17, 18 and development.19, 20, 21Necroptosis can be induced by a number of different extracellular stimuli such as tumor necrosis factor (TNF). TNF stimulation leads to formation of TNF receptor 1 (TNFR1) signaling complex (named complex I), and complex II containing RIP1, TRADD, FAS-associated protein with a death domain (FADD), and caspase-8, of which the activation initiates apoptosis. If cells have high level of RIP3, RIP1 recruits RIP3 to form necrosome containing FADD,22, 23, 24 caspase-8, RIP1, and RIP3, and the cells undergo necroptosis.25, 26 Caspase-8 and FADD negatively regulates necroptosis,27, 28, 29, 30 because RIP1, RIP3, and CYLD are potential substrates of caspase-8.31, 32, 33, 34 Necrosome also suppresses apoptosis but the underlying mechanism has not been described yet. Mixed-lineage kinase domain-like (MLKL) is downstream of RIP3,35, 36 and phosphorylation of MLKL is required for necroptosis.37, 38, 39, 40, 41, 42Apoptosis inducing complex (complex II) and necrosome are both supramolecular complexes.43, 44, 45 A recent study showed that RIP1 and RIP3 form amyloidal fibrils through their RIP homotypic interaction motif46 (RHIM)-mediated polymerization, and suggested that amyloidal structure is essential for necroptosis signaling.47 The RIP1–RIP3 heterodimeric amyloid complex is believed to function as a scaffold that brings signaling proteins into proximity to permit their activation. However, RIP1 and RIP3 also can each form fibrils on their own RHIM domains in vitro. It is unclear how the homo- and hetero-interactions are coordinated and organized on the amyloid scaffold to execute their functions in necroptosis. Here, we used inducible dimerization systems to study the roles of RIP1–RIP1, RIP1–RIP3, and RIP3–RIP3 interactions in necroptosis signaling. Our data suggested that it is the RIP1–RIP3 interaction in the RIP1–RIP3 heterodimeric amyloid complex that empowers to recruit other free RIP3; homodimerization of RIP3 triggers its autophosphorylation and only the phosphorylated RIP3 can recruit MLKL to execute necroptosis. 相似文献
980.