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The dibutyryl analog of cCMP suppressed sperm amplitude of lateral head displacement and hyperactivation. Sperm motility was inhibited by dibutyryl cCMP with a shift toward less linear trajectory sperm movements. The results suggest a role of cCMP as an inhibitory signal on sperm motility patterns related to sperm capacitation. 相似文献
234.
Morin RD Mendez-Lago M Mungall AJ Goya R Mungall KL Corbett RD Johnson NA Severson TM Chiu R Field M Jackman S Krzywinski M Scott DW Trinh DL Tamura-Wells J Li S Firme MR Rogic S Griffith M Chan S Yakovenko O Meyer IM Zhao EY Smailus D Moksa M Chittaranjan S Rimsza L Brooks-Wilson A Spinelli JJ Ben-Neriah S Meissner B Woolcock B Boyle M McDonald H Tam A Zhao Y Delaney A Zeng T Tse K Butterfield Y Birol I Holt R Schein J Horsman DE Moore R Jones SJ Connors JM Hirst M Gascoyne RD Marra MA 《Nature》2011,476(7360):298-303
Follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) are the two most common non-Hodgkin lymphomas (NHLs). Here we sequenced tumour and matched normal DNA from 13 DLBCL cases and one FL case to identify genes with mutations in B-cell NHL. We analysed RNA-seq data from these and another 113 NHLs to identify genes with candidate mutations, and then re-sequenced tumour and matched normal DNA from these cases to confirm 109 genes with multiple somatic mutations. Genes with roles in histone modification were frequent targets of somatic mutation. For example, 32% of DLBCL and 89% of FL cases had somatic mutations in MLL2, which encodes a histone methyltransferase, and 11.4% and 13.4% of DLBCL and FL cases, respectively, had mutations in MEF2B, a calcium-regulated gene that cooperates with CREBBP and EP300 in acetylating histones. Our analysis suggests a previously unappreciated disruption of chromatin biology in lymphomagenesis. 相似文献
235.
CHAN Raymond C K 《科学通报(英文版)》2011,56(32):3409-3415
Increasing efforts to identify alternate expressions of neuropsychiatric disorders that are broader than the DSM or ICD diagnostic criteria needed to diagnose them reflects a growing consensus that multidimensional expressions of neuropsychiatric disorders may advance the search for underlying etiological or modulatory factors. Endophenotypic research can be considered to be one of the most promising strategies to bridge the gap between genomic complexity and the phenotypic heterogeneity observed in neuropsychiatric disorders. However, the majority of endophenotype studies were limited to our western counterparts, very little has been done and initiated by scholars in mainland China. In this paper, we urge the need to establish a potential central consortium for endophenotypes to study neuropsychiatric disorders in mainland China. In particular, we illustrate a potential example of neurological soft signs in following the steps for building the consortium. 相似文献
236.
基于前期的非靶向代谢组学研究结果,在红曲菌发酵液原有营养成分的基础上添加精氨酸、L-苹果酸、D-葡萄糖、烟酰胺、α-酮戊二酸、苯丙氨酸、赖氨酸、焦磷酸硫胺素、黄素单核苷酸、L-乳酸等差异代谢物,对发酵第8天和第15天的红曲色素以及Monacolin K的产量进行了分析。结果表明:精氨酸、苯丙氨酸、赖氨酸以及黄素单核苷酸的添加对Monacolin K产量的提高效果较好,推测氨基酸类物质的添加对Monacolin K产量有促进效果;其中精氨酸添加后效果最为显著,Monacolin K产量约为对照组的2.2~3.7倍。不同含量的烟酰胺对Monacolin K有不同的影响,低含量具有促进作用;而高含量则表现为抑制作用。赖氨酸、苯丙氨酸以及黄素单核苷酸对红曲色素提升效果较好,其中黄素单核苷酸可使红曲色素产量约提高至对照组的1.5~3.0倍。 相似文献
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Predicting protein functions is an important issue in the post-genomic era. This paper studies several network-based kernels
including local linear embedding (LLE) kernel method, diffusion kernel and laplacian kernel to uncover the relationship between
proteins functions and protein-protein interactions (PPI). The author first construct kernels based on PPI networks, then
apply support vector machine (SVM) techniques to classify proteins into different functional groups. The 5-fold cross validation
is then applied to the selected 359 GO terms to compare the performance of different kernels and guilt-by-association methods
including neighbor counting methods and Chi-square methods. Finally, the authors conduct predictions of functions of some
unknown genes and verify the preciseness of our prediction in part by the information of other data source. 相似文献
239.
At least eight inherited human neurodegenerative diseases are caused by expansion of a polyglutamine domain within the respective proteins. This confers dominant toxicity on the proteins, leading to dysfunction and loss of neurons. Expanded polyglutamine proteins form aggregates, including nuclear inclusions (NI), within neurons, possibly due to misfolding of the proteins. NI are ubiquitinated and sequester molecular chaperone proteins and proteasome components, suggesting that disease pathogenesis includes activation of cellular stress pathways to help refold, disaggregate or degrade the mutant disease proteins. Overexpression of specific chaperone proteins reduces polyglutamine aggregation in transfected cells, but whether this alters toxicity is unknown. Using a Drosophila melanogaster model of polyglutamine disease, we show that directed expression of the molecular chaperone HSP70 suppresses polyglutamine-induced neurodegeneration in vivo. Suppression by HSP70 occurred without a visible effect on NI formation, indicating that polyglutamine toxicity can be dissociated from formation of large aggregates. Our studies indicate that HSP70 or related molecular chaperones may provide a means of treating these and other neurodegenerative diseases associated with abnormal protein conformation and toxicity. 相似文献
240.
本实验采用快速溶剂萃取法制备收集100种常用藏药的环己烷、乙酸乙酯和甲醇提取物,并运用MTT法对两个肝癌细胞株HepG2和SMMC-7721进行各提取物的抗肝癌活性测试,同时选用L-02细胞来评价其体外毒性.抗肝癌活性结果显示100种常用藏药中17种藏药材有良好的抗肝癌活性,其IC50值均小于150 μg/mL,其中马兜铃、蓝翠雀花、甘青青兰、掌叶橐吾的乙酸乙酯提取物显示出显著的抗肝癌活性,其IC50值均小于50 μg/mL,但马兜铃乙酸乙酯提取物对正常肝细胞L-02显示出一定的毒性.在进一步的抗HepG2肝癌活性验证中,结果显示蓝翠雀花乙酸乙酯提取物和甘青青兰乙酸乙酯提取物具有显著的抗肝癌活性,两者在抗HepG2肝癌细胞株活性中皆显示出显著的时效和量效关系.运用倒置显微镜以及Hoechst 33258荧光染色法对经过蓝翠雀花乙酸乙酯提取物或甘青青兰乙酸乙酯提取物作用的HepG2细胞形态进行观察,结果提示蓝翠雀花和甘青青兰乙酸乙酯提取物可能是通过诱导HepG2细胞凋亡而显示抗癌活性. 相似文献