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951.
Y-H Fan J Cheng S A Vasudevan J Dou H Zhang R H Patel I T Ma Y Rojas Y Zhao Y Yu H Zhang J M Shohet J G Nuchtern E S Kim J Yang 《Cell death & disease》2013,4(10):e867
Neuroblastoma (NB) is a common pediatric cancer and contributes to more than 15% of all pediatric cancer-related deaths. Unlike adult tumors, recurrent somatic mutations in NB, such as tumor protein 53 (p53) mutations, occur with relative paucity. In addition, p53 downstream function is intact in NB cells with wild-type p53, suggesting that reactivation of p53 may be a viable therapeutic strategy for NB treatment. Herein, we report that the ubiquitin-specific protease 7 (USP7) inhibitor, , potently induces apoptosis in NB cells with an intact USP7-HDM2-p53 axis but not in NB cells with mutant p53 or without human homolog of MDM2 (HDM2) expression. In this study, we found that P22077 stabilized p53 by inducing HDM2 protein degradation in NB cells. P22077 also significantly augmented the cytotoxic effects of doxorubicin (Dox) and etoposide (VP-16) in NB cells with an intact USP7-HDM2-p53 axis. Moreover, P22077 was found to be able to sensitize chemoresistant LA-N-6 NB cells to chemotherapy. In an in vivo orthotopic NB mouse model, P22077 significantly inhibited the xenograft growth of three NB cell lines. Database analysis of NB patients shows that high expression of USP7 significantly predicts poor outcomes. Together, our data strongly suggest that targeting USP7 is a novel concept in the treatment of NB. USP7-specific inhibitors like P22077 may serve not only as a stand-alone therapy but also as an effective adjunct to current chemotherapeutic regimens for treating NB with an intact USP7-HDM2-p53 axis. P22077相似文献
952.
In subtropical China, large‐scale phylogeographic comparisons among multiple sympatric plants with similar ecological preferences are scarce, making generalizations about common response to historical events necessarily tentative. A phylogeographic comparison of two sympatric Chinese beeches (Fagus lucida and F. longipetiolata, 21 and 28 populations, respectively) was conducted to test whether they have responded to historical events in a concerted fashion and to determine whether their phylogeographic structure is exclusively due to Quaternary events or it is also associated with pre‐Quaternary events. Twenty‐three haplotypes were recovered for F. lucida and F. longipetiolata (14 each one and five shared). Both species exhibited a species‐specific mosaic distribution of haplotypes, with many of them being range‐restricted and even private to populations. The two beeches had comparable total haplotype diversity but F. lucida had much higher within‐population diversity than F. longipetiolata. Molecular dating showed that the time to most recent common ancestor of all haplotypes was 6.36 Ma, with most haplotypes differentiating during the Quaternary. [Correction added on 14 October 2013, after first online publication: the time unit has been corrected to ‘6.36’.] Our results support a late Miocene origin and southwards colonization of Chinese beeches when the aridity in Central Asia intensified and the monsoon climate began to dominate the East Asia. During the Quaternary, long‐term isolation in subtropical mountains of China coupled with limited gene flow would have lead to the current species‐specific mosaic distribution of lineages. 相似文献
953.
954.
Jianjun Wang Ji Shen Yucheng Wu Chen Tu Janne Soininen James C Stegen Jizheng He Xingqi Liu Lu Zhang Enlou Zhang 《The ISME journal》2013,7(7):1310-1321
Increasing evidence has emerged for non-random spatial distributions of microbes, but knowledge of the processes that cause variation in microbial assemblage among ecosystems is lacking. For instance, some studies showed that deterministic processes such as habitat specialization are important, while other studies hold that bacterial communities are assembled by stochastic forces. Here we examine the relative influence of deterministic and stochastic processes for bacterial communities from subsurface environments, stream biofilm, lake water, lake sediment and soil using pyrosequencing of the 16S ribosomal RNA gene. We show that there is a general pattern in phylogenetic signal in species ecological niches across recent evolutionary time for all studied habitats, enabling us to infer the influences of community assembly processes from patterns of phylogenetic turnover in community composition. The phylogenetic dissimilarities among-habitat types were significantly higher than within them, and the communities were clustered according to their original habitat types. For communities within-habitat types, the highest phylogenetic turnover rate through space was observed in subsurface environments, followed by stream biofilm on mountainsides, whereas the sediment assemblages across regional scales showed the lowest turnover rate. Quantifying phylogenetic turnover as the deviation from a null expectation suggested that measured environmental variables imposed strong selection on bacterial communities for nearly all sample groups. For three sample groups, spatial distance reflected unmeasured environmental variables that impose selection, as opposed to spatial isolation. Such characterization of spatial and environmental variables proved essential for proper interpretation of partial Mantel results based on observed beta diversity metrics. In summary, our results clearly indicate a dominant role of deterministic processes on bacterial assemblages and highlight that bacteria show strong habitat associations that have likely emerged through evolutionary adaptation. 相似文献
955.
Jason N Woodhouse Lu Fan Mark V Brown Torsten Thomas Brett A Neilan 《The ISME journal》2013,7(9):1842-1851
The biosynthesis of non-ribosomal peptide and polyketide natural products is facilitated by multimodular enzymes that contain domains responsible for the sequential condensation of amino and carboxylic subunits. These conserved domains provide molecular targets for the discovery of natural products from microbial metagenomes. This study demonstrates the application of tag-encoded FLX amplicon pyrosequencing (TEFAP) targeting non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) genes as a method for determining the identity and diversity of natural product biosynthesis genes. To validate this approach, we assessed the diversity of NRPS and PKS genes within the microbiomes of six Australian marine sponge species using both TEFAP and metagenomic whole-genome shotgun sequencing approaches. The TEFAP approach identified 100 novel ketosynthase (KS) domain sequences and 400 novel condensation domain sequences within the microbiomes of the six sponges. The diversity of KS domains within the microbiome of a single sponge species Scopalina sp. exceeded that of any previously surveyed marine sponge. Furthermore, this study represented the first to target the condensation domain from NRPS biosynthesis and resulted in the identification of a novel condensation domain lineage. This study highlights the untapped potential of Australian marine sponges for the isolation of novel bioactive natural products. Furthermore, this study demonstrates that TEFAP approaches can be applied to functional genes, involved in natural product biosynthesis, as a tool to aid natural product discovery. It is envisaged that this approach will be used across multiple environments, offering an insight into the biological processes that influence the production of secondary metabolites. 相似文献
956.
A high efficient Supply Chain (SC) would bring great benefits to an enterprise such as integrated resources, reduced logistics costs, improved logistics efficiency and high quality of overall level of services. So it is important to research various methods, performance indicator systems and technology for evaluating, monitoring, predicting and optimizing the performance of a SC. In this paper, the existing performance indicator systems and methods are discussed and evaluated. Various nature-inspired algorithms are reviewed and their applications for SC Performance Evaluation (PE) are discussed. Then, a model is proposed and developed using 5 Dimensional Balanced Scorecard (5DBSC) and LMBP (Levenberg-Marquardt Back Propagation) neural network for SC PE. A program is written using Matlab tool box to implement the model based on the practical values of the 14 indicators of 5DBSC of a given previous period. This model can be used to evaluate, predict and optimize the performance of a SC. The analysis results of a case study of a company show that the proposed model is valid, reliable and effective. The convergence speed is faster than that in the previous work. 相似文献
957.
Chunyan Chen Tian Shen Fei Tian Ping Lin Qingtian Li Zelin Cui Yajuan Zhang Min Xue Jing Ye Xiaokui Guo YuhuaZhou 《Acta biochimica et biophysica Sinica》2013,(12):1039-1048
Community-acquired pneumonia (CAP) is a major concern in hospitals and the bacterial community of which has not been systemically discussed yet. Sputum from patients in the acute stages is a kind of accessible sample reflecting its fea- tures. In our study, we analyzed 45 sputum samples from 45 patients with CAP. Eighteen sputum samples from healthy people were chosen as the controls. Pyrosequencing of the 16s rDNA V3 hypervariable regions of aH the bacteria con- tained in the sputum was used as a culture-independent method to disclose the community constitution. Also, our published data for hospital-acquired pneumonia (HAP) in sputum was used for comparison. By pyrosequencing, 〉90,000 DNA reads were detected. After being analyzed by tools in the Ribosomal Database Project, the reads were clas- sified into five main phyla and 〉100 genera. At the phyla level, the reads' distribution of CAP is similar to that of healthy people and at genera level, the occurrence of each genus possesses their feature in three categories. Genera such as Streptococcus and Neisseria showed stability in their percentages, indicating that such genera are rarely affected by exogenous bacteria or antibiotics. The role of other genera such as Moraxella and Rothia in CAP should be emphasized. According to our analysis, the bacterial communities of CAP are with slight change when compared with those of healthy people, but have a large gap between HAP. Meanwhile, Rothia might be an important endogenous pneumonia-causing factor. 相似文献
958.
Fang Gong Lingtao Ding Donglin Jiang Chun Zhang Weihong Shen Yuhong Pan 《Acta biochimica et biophysica Sinica》2013,(11):982-984
The seroprevalence of human cytomegalovirus (HCMV) in adults increased steadily from 55% in developed countries to over 90% in developing countries like China [1]. As all her- pesviruses, HCMV establishes lifelong latency after primary infection. In immunocompetent individuals, host immune responses prevent the development of overt HCMV diseases. However, in immunoeompromised people who suffer from burn injuries, HCMV reactivation has been shown to lead to significant diseases with considerable morbidity and mortal- ity [2-4]. Recently, increasing evidence has suggested that HCMV reactivation might have been considerably underesti- mated in burn patients [5,6]. Review of the available litera- ture identifies 〉50% of HCMV antibody-positive burn patients may reactivate this virus [5,6]. Although the exact mechanisms of HCMV reactivation are still not clearly under- stood, the immune system and host genetics are thought to be the non-behavioral factors determining the acquisition of a reactivation. 相似文献
959.
Xiaoqiang Guo Yuejia Wangi Yongqing Shen Yingjie Gao Yanzhong Chang Xianglin Duan 《Acta biochimica et biophysica Sinica》2013,(11):912-920
Alcoholic liver disease (ALD) is a serious fiver problem in western countries. Our previous study has demonstrated that vitamin C plays a protective role in ALD. The vitamin C homeostasis is tightly regulated by sodium-dependent vitamin C transporters (SVCTs) 1 and 2. But the role of two SVCTs in ALD is less understood. In this study, we exam- ined the expression patterns of two SVCTs in mice after alcohol consumption. Our results suggested that alcohol con- sumption obviously increased the expression of two SVCTs in liver and SVCT1 in kidney and intestine, which is important for vitamin C absorption. Vitamin C supplement increased the sera vitamin C content and ameliorated the symptom of ALD. Intestinal absorption and renal re-absorption mediated by SVCTI are key factors to increase the sera vitamin C content after alcohol consumption. We proposed that both reactive oxygen species and low vitamin C concentration regulate the expression of SVCTs, and the protective role of vitamin C is mediated by suppressing the stability of hypoxia-inducible factor-loL. Thus, our study is significant for the understanding of vitamin C homeostasis in ALD and for better use of other antioxidants in ALD therapy. 相似文献
960.
Xiang-Shun Cui Xing-Hui Shen Shao-Chen Sun Sun-Wha Cho Young-Tae Heo Yong-Kook Kang Teruhiko Wakayama 《遗传学报》2013,40(4):189-200
MicroRNAs (miRNAs) are a class of highly conserved small non-coding RNA molecules that play a pivotal role in several cellular functions. In this study, miRNA and messenger RNA (mRNA) profiles were examined by Illumina microarray in mouse embryonic stem cells (ESCs) derived from parthenogenetic, androgenetic, and fertilized blastocysts. The global analysis of miRNA-mRNA target pairs provided insight into the role of miRNAs in gene expression. Results showed that a total of 125 miRNAs and 2394 mRNAs were differentially expressed between androgenetic ESCs (aESCs) and fertilized ESCs (fESCs), a total of 42 miRNAs and 87 mRNAs were differentially expressed between parthenogenetic ESCs (pESCs) and fESCs, and a total of 99 miRNAs and 1788 mRNAs were differentially expressed between aESCs and pESCs. In addition, a total of 575, 5 and 376 miRNA-mRNA target pairs were observed in aESCs vs. fESCs, pESCs vs. fESCs, and aESCs vs. pESCs, respectively. Furthermore, 15 known imprinted genes and 16 putative uniparentally expressed miRNAs with high expression levels were confirmed by both microarray and real-time RT-PCR. Finally, transfection of miRNA inhibitors was performed to validate the regulatory relationship between putative maternally expressed miRNAs and target mRNAs. Inhibition of miR-880 increased the expression of Peg3, Dyrk1b, and Prrg2 mRNA, inhibition of miR-363 increased the expression of Nfat5 and Soat1 mRNA, and inhibition of miR-883b-5p increased Nfat5, Tacstd2, and Ppapdc1 mRNA. These results warrant a functional study to fully understand the underlying regulation of genomic imprinting in early embryo development. 相似文献