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101.
Martin J Blaser Maria G Dominguez-Bello Monica Contreras Magda Magris Glida Hidalgo Isidoro Estrada Zhan Gao Jose C Clemente Elizabeth K Costello Rob Knight 《The ISME journal》2013,7(1):85-95
The human skin harbors complex bacterial communities. Prior studies showing high inter-individual variation focused on subjects from developed countries. We therefore compared cutaneous bacterial communities of Amerindians in the Venezuelan Amazon with subjects in the United States. Forearm skin specimens were studied from healthy Amerindians in Platanillal village in Amazonas State, and from healthy persons in New York and Colorado. All skin sampling used similar swab/buffer techniques. Multiplexed V2-targeted 16S rRNA gene pyrosequencing yielded high quality sequences from 112 samples. The results show 20 phyla, with three (Proteobacteria, Firmicutes, Actinobacteria) predominating. US residents and Venezuelan Amerindians had significantly different forearm skin bacterial community compositions, with United States dominated by Propionibacterium. Among the Amerindians, there was a deep split based on bacterial community membership, with 30 and 42 samples, respectively, falling into each of the two groups, not associated with age, gender, or body mass index. One Amerindian group had diversity similar to the United States, but was dominated by Staphylococcus rather than Propionibacterium. The other Amerindian group was significantly more diverse and even than the US or the other Amerindian group, and featured a broad range of Proteobacteria. The results provide evidence that ethnicity, lifestyle and/or geography are associated with the structure of human cutaneous bacterial communities. 相似文献
102.
Aixia Li Wenlong Yang Xueyuan Lou Dongcheng Liu Jiazhu Sun Xiaoli Guo Jing Wang Yiwen Li Kehui Zhan Hong-Qing Ling Aimin Zhang 《植物学报(英文版)》2013,55(11):1026-1037
Plant height is an important agronomic trait. Dramatic increase in wheat yield during the "green revolution" is mainly due to the widespread utilization of the Reduced height (Rht)-1gene. We analyzed the natural allelic variations of three homoeologous loci Rht-A1, Rht-B1, and Rht-D1 in Chinese wheat (Triticum aestivum L.) micro-core collections and the Rht-B1/D1 genotypes in over 1,500 bred cultivars and germplasms using a modified EcoTILLING. We identified six new Rht-A1 allelic variations (Rht-Alb-g), eight new Rht-B1 allelic variations (Rht-Blh-o), and six new Rht-D1 allelic variations (Rht-Dle-j). These allelic variations contain single nucleotide polymorphisms (SNPs) or small insertions and deletions in the coding or uncoding regions, involving two frame-shift mutations and 15 missenses. Of which, Rht-Dle and Rht-Dlh resulted in the loss of interactions of GID1-DELLA-GID2, Rht-Blicould increase plant height. We found that the Rht-Blh contains the same SNPs and 197 bp fragment insertion as reported in Rht-Blc. Further detection of Rht-Blh in Tibet wheat germplasms and wheat relatives indicated that Rht-Blc may originate from Rht-Blh. These results suggest rich genetic diversity at the Rht-1 loci and provide new resources for wheat breeding. 相似文献
103.
Takayoshi Suzuki Yuki Kasuya Yukihiro Itoh Yosuke Ota Peng Zhan Kaori Asamitsu Hidehiko Nakagawa Takashi Okamoto Naoki Miyata 《PloS one》2013,8(7)
To find histone deacetylase 3 (HDAC3)-selective inhibitors, a series of 504 candidates was assembled using “click chemistry”, by reacting nine alkynes bearing a zinc-binding group with 56 azide building blocks in the presence of Cu(I) catalyst. Screening of the 504-member triazole library against HDAC3 and other HDAC isozymes led to the identification of potent and selective HDAC3 inhibitors T247 and T326. These compounds showed potent HDAC3 inhibition with submicromolar IC50s, whereas they did not strongly inhibit other isozymes. Compounds T247 and T326 also induced a dose-dependent selective increase of NF-κB acetylation in human colon cancer HCT116 cells, indicating selective inhibition of HDAC3 in the cells. In addition, these HDAC3-selective inhibitors induced growth inhibition of cancer cells, and activated HIV gene expression in latent HIV-infected cells. These findings indicate that HDAC3-selective inhibitors are promising candidates for anticancer drugs and antiviral agents. This work also suggests the usefulness of the click chemistry approach to find isozyme-selective HDAC inhibitors. 相似文献
104.
Zuoxu Fan Tao Ji Shu Wan Yaoyao Wu Yu Zhu Feng Xiao Renya Zhan 《Cancer epidemiology》2013,37(1):39-45
Objective: The relationship between smoking and the development of meningioma has been investigated in several epidemiological studies. However, the results of these studies are inconsistent. We conducted a meta-analysis in order to identify any potential association. Methods: PubMed, the Cochrane Library, and EMBASE databases were searched to identify relevant articles that investigated the risk of meningioma following cigarette smoking. Two researchers evaluated study eligibility and extracted the data independently, and disagreements were resolved by discussion. The variables used to estimate the pooled risk of smoking in meningioma development were the multivariate-adjusted risk estimates presented in the literature. Results: Seven case–control and two cohort studies were included in this meta-analysis. The pooled estimated risks associated with ever smoking for meningioma were 1.02 (95% confidence interval (CI): 0.85–1.21) in the case–control studies, 0.93 (95% CI: 0.83–1.04) in the cohort studies and 0.95 (95% CI: 0.87–1.05, P = 0.32) in all studies when the cohort and case–control data were combined. Subgroup analyses suggested that the risk estimates were 1.49 (95% CI: 1.06–2.09, P = 0.02), 0.86 (95% CI: 0.65–1.13), 0.79 (95% CI: 0.50–1.25) and 0.84 (95% CI: 0.69–1.03) for men, women, current and past smoking respectively. Sensitivity analyses restricted to studies with different adjustments for confounders yielded similar results. No evidence of publication bias was observed. Conclusion: Our meta-analysis suggests that there is no association between ever smoking and the risk of meningioma. However, a small but significant risk elevation is present among men smokers. 相似文献
105.
Weiping?Zhu Yiming?Zhao Jiamin?Zhou Xin?Wang Qi?Pan Ning?Zhang Longrong?Wang Miao?Wang Dihua?Zhan Zeyang?Liu Xigan?He Dening?Ma Shuang?Liu Lu?WangEmail author 《Journal of hematology & oncology》2016,9(1):127
Background
Monoacylglycerol lipase (MAGL), a critical lipolytic enzyme, has emerged as a key regulator of tumor progression, yet its biological function and clinical significance in hepatocellular carcinoma (HCC) is still unknown.Methods
In this study, we used a tissue microarray containing samples from 170 HCC patients to evaluate the expression of MAGL and its correlation with other clinicopathologic characteristics. In addition, we investigated the regulating effects of MAGL on various HCC lines. Finally, we identified the NF-κB signaling pathway participated in MAGL-mediated epithelial-mesenchymal transition (EMT) using HCC cell lines with different metastatic potentials.Results
The expression of MAGL was significantly higher in HCC tumors than in matched peritumor tissues. Specifically, high MAGL expression was found in tumors with larger tumor size, microvascular invasion, poor differentiation, or advanced TNM stage. In addition, the clinical prognosis for the MAGLhigh group was markedly poorer than that for the MAGLlow group in the 1-, 3-, and 5-year overall survival times and recurrence rates of HCC patients. MAGL expression was an independent prognostic factor for both survival and recurrence after curative resection. Furthermore, the upregulation of MAGL in HCC cells promoted cell growth and invasiveness abilities, and accompanied by EMT. In contrast, downregulation of MAGL obviously inhibited these characteristics. Moreover, further investigations verified that MAGL facilitates HCC progression via NF-κB-mediated EMT process.Conclusions
Our findings demonstrate MAGL could promote HCC progression by the induction of EMT and suggest a potential therapeutic target, as well as a biomarker for prognosis, in patients with HCC.106.
Jiandong Zheng Xixiang Huo Yang Huai Lin Xiao Hui Jiang John Klena Carolyn M. Greene Xuesen Xing Jigui Huang Shali Liu Youxing Peng Hui Yang Jun Luo Zhibin Peng Linlin Liu Maoyi Chen Hui Chen Yuzhi Zhang Danqin Huang Xuhua Guan Luzhao Feng Faxian Zhan Dale J. Hu Jay K. Varma Hongjie Yu 《PloS one》2016,11(3)
107.
108.
Yilong Fu Lai-Chun Ong Sudhir H. Ranganath Lin Zheng Irene Kee Wenbo Zhan Sidney Yu Pierce K. H. Chow Chi-Hwa Wang 《PloS one》2016,11(2)
Early diagnosis of low grade glioma has been a challenge to clinicians. Positron Emission Tomography (PET) using 18F-FDG as a radio-tracer has limited utility in this area because of the high background in normal brain tissue. Other radiotracers such as 18F-Fluorocholine (18F-FCH) could provide better contrast between tumor and normal brain tissue but with high incidence of false positives. In this study, the potential application of a dual tracer 18F-FCH/18F-FDG-PET is investigated in order to improve the sensitivity of PET imaging for low grade glioma diagnosis based on a mouse orthotopic xenograft model. BALB/c nude mice with and without orthotopic glioma xenografts from U87 MG-luc2 glioma cell line are used for the study. The animals are subjected to 18F-FCH and 18F-FDG PET imaging, and images acquired from two separate scans are superimposed for analysis. The 18F-FCH counts are subtracted from the merged images to identify the tumor. Micro-CT, bioluminescence imaging (BLI), histology and measurement of the tumor diameter are also conducted for comparison. Results show that there is a significant contrast in 18F-FCH uptake between tumor and normal brain tissue (2.65 ± 0.98), but with a high false positive rate of 28.6%. The difficulty of identifying the tumor by 18F-FDG only is also proved in this study. All the tumors can be detected based on the dual tracer technique of 18F-FCH/ 18F-FDG-PET imaging in this study, while the false-positive caused by 18F-FCH can be eliminated. Dual tracer 18F-FCH/18F-FDG PET imaging has the potential to improve the visualization of low grade glioma. 18F-FCH delineates tumor areas and the tumor can be identified by subtracting the 18F-FCH counts. The sensitivity was over 95%. Further studies are required to evaluate the possibility of applying this technique in clinical trials. 相似文献
109.
110.
Jingbo Wu Feng Liu Rulin Zhan Guoping Li Yanlong Zhao Chang Jinmei Yanbiao He 《Biotechnology letters》2016,38(5):835-840