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211.
Metastasis to the liver is a main factor in colorectal cancer mortality. Previous studies suggest that chronic psychological stress is important in cancer progression, but its effect on liver metastasis has not been investigated. To address this, we established a liver metastasis model in BALB/c nude mice to investigate the role of chronic stress in liver metastasis. Our data suggest that chronic stress elevates catecholamine levels and promotes liver metastasis. Chronic stress was also associated with increased tumor associated macrophages infiltration into the primary tumor and increased the expression of metastatic genes. Interestingly, β-blocker treatment reversed the effects of chronic stress on liver metastasis. Our results suggest the β-adrenergic signaling pathway is involved in regulating colorectal cancer progression and liver metastasis. Additionally, we submit that adjunctive therapy with a β-blocker may complement existing colorectal cancer therapies. 相似文献
212.
Graph Theoretical Analysis of BOLD Functional Connectivity during Human Sleep without EEG Monitoring
Background
Functional brain networks of human have been revealed to have small-world properties by both analyzing electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI) time series.Methods & Results
In our study, by using graph theoretical analysis, we attempted to investigate the changes of paralimbic-limbic cortex between wake and sleep states. Ten healthy young people were recruited to our experiment. Data from 2 subjects were excluded for the reason that they had not fallen asleep during the experiment. For each subject, blood oxygen level dependency (BOLD) images were acquired to analyze brain network, and peripheral pulse signals were obtained continuously to identify if the subject was in sleep periods. Results of fMRI showed that brain networks exhibited stronger small-world characteristics during sleep state as compared to wake state, which was in consistent with previous studies using EEG synchronization. Moreover, we observed that compared with wake state, paralimbic-limbic cortex had less connectivity with neocortical system and centrencephalic structure in sleep.Conclusions
In conclusion, this is the first study, to our knowledge, has observed that small-world properties of brain functional networks altered when human sleeps without EEG synchronization. Moreover, we speculate that paralimbic-limbic cortex organization owns an efficient defense mechanism responsible for suppressing the external environment interference when humans sleep, which is consistent with the hypothesis that the paralimbic-limbic cortex may be functionally disconnected from brain regions which directly mediate their interactions with the external environment. Our findings also provide a reasonable explanation why stable sleep exhibits homeostasis which is far less susceptible to outside world. 相似文献213.
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216.
Excessive Retinoic Acid Impaired Proliferation and Differentiation of Human Fetal Palatal Chondrocytes (hFPCs) 下载免费PDF全文
Ning Li Yusheng Xu Huanhuan Zhang Liyun Gao Jue Li Yongchao Wang Zhan Gao Xinjuan Pan Xiaozhuan Liu Xing Li Zengli Yu 《Birth defects research. Part B, Developmental and reproductive toxicology》2014,101(3):276-282
Chondrocyte proliferation and differentiation is a fundamental process during hard palatogenesis. Excessive retinoic acid (RA), the biologically most active metabolite of vitamin A, has been reported to adversely affect chondrogenesis. The aim of this study was to investigate the mechanisms underlying RA‐induced chondrocyte differentiation by using human fetal palatal chondrocytes (hFPCs) aging about 9 weeks of amenorrhea. RA treatment inhibited proliferation and induced apoptosis in hFPCs. Alkaline phosphatase activity assay, quantitative alcian blue staining, and real‐time PCR analysis revealed that RA treatment stimulated hFPCs to undergo maturation and terminal differentiation, as demonstrated by decreased chondrogenic markers and increased osteogenic markers. Further studies demonstrated that RA treatment increased Wnt/β‐catenin signaling, as demonstrated by Wnt/β‐catenin target gene expression analysis and a luciferase‐based β‐catenin–activated reporter assay. To address the role of Wnt/β‐catenin signaling, we treated hFPCs with Dickkopf‐related protein 1, an extracellular inhibitor of Wnt/β‐catenin signaling, and the observed all‐trans retinoic acid–mediated increases in nuclear accumulation of β‐catenin, alkaline phosphatase activity, and type I collagen mRNA were attenuated, suggesting that RA modulated Wnt signaling at ligand–receptor level. In summary, excessive all‐trans retinoic acid inhibited proliferation and promoted ossification of hFPCs by upregulation of Wnt/β‐catenin signaling 相似文献
217.
Jue Ruan Lan Jiang Zechen Chong Qiang Gong Heng Li Chunyan Li Yong Tao Caihong Zheng Weiwei Zhai David Turissini Charles H Cannon Xuemei Lu Chung-I Wu 《BMC genomics》2013,14(1)
Background
Usually, next generation sequencing (NGS) technology has the property of ultra-high throughput but the read length is remarkably short compared to conventional Sanger sequencing. Paired-end NGS could computationally extend the read length but with a lot of practical inconvenience because of the inherent gaps. Now that Illumina paired-end sequencing has the ability of read both ends from 600 bp or even 800 bp DNA fragments, how to fill in the gaps between paired ends to produce accurate long reads is intriguing but challenging.Results
We have developed a new technology, referred to as pseudo-Sanger (PS) sequencing. It tries to fill in the gaps between paired ends and could generate near error-free sequences equivalent to the conventional Sanger reads in length but with the high throughput of the Next Generation Sequencing. The major novelty of PS method lies on that the gap filling is based on local assembly of paired-end reads which have overlaps with at either end. Thus, we are able to fill in the gaps in repetitive genomic region correctly. The PS sequencing starts with short reads from NGS platforms, using a series of paired-end libraries of stepwise decreasing insert sizes. A computational method is introduced to transform these special paired-end reads into long and near error-free PS sequences, which correspond in length to those with the largest insert sizes. The PS construction has 3 advantages over untransformed reads: gap filling, error correction and heterozygote tolerance. Among the many applications of the PS construction is de novo genome assembly, which we tested in this study. Assembly of PS reads from a non-isogenic strain of Drosophila melanogaster yields an N50 contig of 190 kb, a 5 fold improvement over the existing de novo assembly methods and a 3 fold advantage over the assembly of long reads from 454 sequencing.Conclusions
Our method generated near error-free long reads from NGS paired-end sequencing. We demonstrated that de novo assembly could benefit a lot from these Sanger-like reads. Besides, the characteristic of the long reads could be applied to such applications as structural variations detection and metagenomics.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-14-711) contains supplementary material, which is available to authorized users. 相似文献218.
219.
目的:探讨PTEN蛋白在前列腺癌组织中的表达及其临床意义。方法:应用免疫组织化学S-P方法,检测前列腺癌及良性前列腺增生组织中PTEN蛋白的表达。结果:PTEN蛋白表达阳性随肿瘤细胞病理分级、临床分期的增高,PTEN蛋白阳性表达率降低。结论:PTEN蛋白异常表达在前列腺癌的进展中有重要作用,检测PTEN蛋白的表达有助于判断病情及预后。 相似文献
220.
Krauss J Farzaneh-Far R Puterman E Na B Lin J Epel E Blackburn E Whooley MA 《PloS one》2011,6(11):e26983