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161.
Background
Somatic cell nuclear transfer (SCNT) is a promising technique to produce transgenic cloned mammalian, including transgenic goats which may produce Human Lactoferrin (hLF). However, success percentage of SCNT is low, because of gestational and neonatal failure of transgenic embryos. According to the studies on cattle and mice, DNA methylation of some imprinted genes, which plays a vital role in the reprogramming of embryo in NT maybe an underlying mechanism.Methodology/Principal Findings
Fibroblast cells were derived from the ear of a two-month-old goat. The vector expressing hLF was constructed and transfected into fibroblasts. G418 selection, EGFP expression, PCR, and cell cycle distribution were applied sequentially to select transgenic cells clones. After NT and embryo transfer, five transgenic cloned goats were obtained from 240 cloned transgenic embryos. These transgenic goats were identified by 8 microsatellites genotyping and southern blot. Of the five transgenic goats, 3 were lived after birth, while 2 were dead during gestation. We compared differential methylation regions (DMR) pattern of two paternally imprinted genes (H19 and IGF2R) of the ear tissues from the lived transgenic goats, dead transgenic goats, and control goats from natural reproduction. Hyper-methylation pattern appeared in cloned aborted goats, while methylation status was relatively normal in cloned lived goats compared with normal goats.Conclusions/Significance
In this study, we generated five hLF transgenic cloned goats by SCNT. This is the first time the DNA methylation of lived and dead transgenic cloned goats was compared. The results demonstrated that the methylation status of DMRs of H19 and IGF2R were different in lived and dead transgenic goats and therefore this may be potentially used to assess the reprogramming status of transgenic cloned goats. Understanding the pattern of gene imprinting may be useful to improve cloning techniques in future. 相似文献162.
Guihua Jiang Xue Wen Yingwei Qiu Ruibin Zhang Junjing Wang Meng Li Xiaofen Ma Junzhang Tian Ruiwang Huang 《PloS one》2013,8(12)
Neuroimaging studies have shown that heroin addiction is related to abnormalities in widespread local regions and in the functional connectivity of the brain. However, little is known about whether heroin addiction changes the topological organization of whole-brain functional networks. Seventeen heroin-dependent individuals (HDIs) and 15 age-, gender-matched normal controls (NCs) were enrolled, and the resting-state functional magnetic resonance images (RS-fMRI) were acquired from these subjects. We constructed the brain functional networks of HDIs and NCs, and compared the between-group differences in network topological properties using graph theory method. We found that the HDIs showed decreases in the normalized clustering coefficient and in small-worldness compared to the NCs. Furthermore, the HDIs exhibited significantly decreased nodal centralities primarily in regions of cognitive control network, including the bilateral middle cingulate gyrus, left middle frontal gyrus, and right precuneus, but significantly increased nodal centralities primarily in the left hippocampus. The between-group differences in nodal centralities were not corrected by multiple comparisons suggesting these should be considered as an exploratory analysis. Moreover, nodal centralities in the left hippocampus were positively correlated with the duration of heroin addiction. Overall, our results indicated that disruptions occur in the whole-brain functional networks of HDIs, findings which may be helpful in further understanding the mechanisms underlying heroin addiction. 相似文献
163.
Objectives
To assess the feasibility of low-dose prospective ECG-gated dual-source CT (DSCT) in detecting airway anomalies in pediatric patients with cardiovascular anomalies compared with flexible tracheobronchoscopy (FTB).Methods
33 pediatrics with respiratory symptoms who had been revealed cardiovascular anomalies by transthoracic echocardiography underwent FTB and contrast material–enhanced prospective ECG-triggering CT were enrolled. The study was approved by our institution review board and written informed consent was obtained from all patients’ guardian. DSCT examinations were performed to detect cardiovascular abnormalities using weight-adjusted low–dose protocol. Two radiologists independently performed CT image analysis. The FTB reports were reviewed by an experienced pulmonologist. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of DSCT in the detection of airway anomalies were assessed. The tracheobronchial stenoses revealed on FTB were graded. Effective radiation dose was calculated.Results
Thirty cases were diagnosed with tracheobronchial narrowing and/or abnormality in 33 patients by FTB, while 3 patients had normal FTB findings. Twenty-eight cases were diagnosed with airway anomalies by CT, of which 27 were correct positive. 3 patients with normal findings at CT had findings of tracheobronchial narrowing due to tracheobronchomalacia at inspiration at FTB. Sensitivity and specificity of CT were 90.0% (95% CI: 72.3%, 97.4%) and 66.7% (95% CI: 12.5 %, 98.2 %), respectively. PPV and NPV were 96.4% (95% CI: 79.8 %, 99.8%) and 40.0% (95% CI: 7.3%, 83.0%), respectively. Overall accuracy of DSCT in detecting airway anomalies in pediatrics with cardiovascular anomalies was 87.9% (95% CI: 74.5%, 97.6%). In grading of tracheobronchial stenosis, images from CT correlated closely (r = 0.89) with those of FTB. Mean effective dose was 0.60±0.20 mSv.Conclusion
In pediatric patients, ECG-triggered CT to evaluate congenital cardiovascular anomalies can also be used to diagnose and characterize fixed airway involvement in relation to the vascular structures. 相似文献164.
165.
Background
No attention has been paid on comparing a set of genome sequences crossing genetic components and biological categories with far divergence over large size range. We define it as the systematic comparative genomics and aim to develop the methodology.Results
First, we create a method, GenomeFingerprinter, to unambiguously produce a set of three-dimensional coordinates from a sequence, followed by one three-dimensional plot and six two-dimensional trajectory projections, to illustrate the genome fingerprint of a given genome sequence. Second, we develop a set of concepts and tools, and thereby establish a method called the universal genome fingerprint analysis (UGFA). Particularly, we define the total genetic component configuration (TGCC) (including chromosome, plasmid, and phage) for describing a strain as a systematic unit, the universal genome fingerprint map (UGFM) of TGCC for differentiating strains as a universal system, and the systematic comparative genomics (SCG) for comparing a set of genomes crossing genetic components and biological categories. Third, we construct a method of quantitative analysis to compare two genomes by using the outcome dataset of genome fingerprint analysis. Specifically, we define the geometric center and its geometric mean for a given genome fingerprint map, followed by the Euclidean distance, the differentiate rate, and the weighted differentiate rate to quantitatively describe the difference between two genomes of comparison. Moreover, we demonstrate the applications through case studies on various genome sequences, giving tremendous insights into the critical issues in microbial genomics and taxonomy.Conclusions
We have created a method, GenomeFingerprinter, for rapidly computing, geometrically visualizing, intuitively comparing a set of genomes at genome fingerprint level, and hence established a method called the universal genome fingerprint analysis, as well as developed a method of quantitative analysis of the outcome dataset. These have set up the methodology of systematic comparative genomics based on the genome fingerprint analysis. 相似文献166.
Yuhong Zhang Xiaolu Xu Xiaojin Zhou Rumei Chen Peilong Yang Qingchang Meng Kun Meng Huiying Luo Jianhua Yuan Bin Yao Wei Zhang 《PloS one》2013,8(12)
Background
Incorporation of exogenous glucanase into animal feed is common practice to remove glucan, one of the anti-nutritional factors, for efficient nutrition absorption. The acidic endo-β-1,3-1,4-glucanase (Bgl7A) from Bispora sp. MEY-1 has excellent properties and represents a potential enzyme supplement to animal feed.Methodology/Principal Findings
Here we successfully developed a transgenic maize producing a high level of Bgl7AM (codon modified Bgl7A) by constructing a recombinant vector driven by the embryo-specific promoter ZM-leg1A. Southern and Western blot analysis indicated the stable integration and specific expression of the transgene in maize seeds over four generations. The β-glucanase activity of the transgenic maize seeds reached up to 779,800 U/kg, about 236-fold higher than that of non-transgenic maize. The β-glucanase derived from the transgenic maize seeds had an optimal pH of 4.0 and was stable at pH 1.0–8.0, which is in agreement with the normal environment of digestive tract.Conclusion/Significance
Our study offers a transgenic maize line that could be directly used in animal feed without any glucanase production, purification and supplementation, consequently simplifying the feed enzyme processing procedure. 相似文献167.
Pengsheng Chen Sisi Pang Naiquan Yang Haoyu Meng Jia Liu Ningtian Zhou Min Zhang Zhihui Xu Wei Gao Bo Chen Zhengxian Tao Liansheng Wang Zhijian Yang 《PloS one》2013,8(11)
The fruit of Schisandra chinensis has been used in the traditional Chinese medicine for thousands of years. Accumulating evidence suggests that Schisandrin B (Sch B) has cardioprotection effect on myocardial ischemia in
vitro. However, it is unclear whether Sch B has beneficial effects on continuous myocardial ischemia in vivo. The aim of the present study was to investigate whether Sch B could improve cardiac function and attenuate myocardial remodeling after myocardial infarction (MI) in mice. Mice model of MI was established by permanent ligation of the left anterior descending (LAD) coronary artery. Then the MI mice were randomly treated with Sch B or vehicle alone. After treatment for 3 weeks, Sch B could increase survival rate, improve heart function and decrease infarct size compared with vehicle. Moreover, Sch B could down-regulate some inflammatory cytokines, activate eNOS pathway, inhibit cell apoptosis, and enhance cell proliferation. Further in vitro study on H9c2 cells showed similar effects of Sch B on prevention of hypoxia-induced inflammation and cell apoptosis. Taken together, our results demonstrate that Sch B can reduce inflammation, inhibit apoptosis, and improve cardiac function after ischemic injury. It represents a potential novel therapeutic approach for treatment of ischemic heart disease. 相似文献
168.
Previously, we have documented that isolated autophagosomes from tumor cells could efficiently cross-prime tumor-reactive naïve T cells and mediate tumor regression in preclinical mouse models. However, the effect of tumor-derived autophagosomes, here we refer as to DRibbles, on B cells has not been studied so far. At present study, we found that DRibbles generated from a murine hepatoma cell line Hep1-6, induced B-cell activation after intravenous injection into mice. B-cell populations were significantly expanded and the production of Hep1-6 tumor-specific antibodies was successfully induced. Moreover, in vitro studies showed that DRibbles could induce more efficient B-cell proliferation and activation, antibody production, and cytokine secretion than whole tumor cell lysates. Notably, we found that B-cell activation required proteins but not DNA in the DRibbles. We further showed that B cells could capture DRibbles and present antigens in the DRibbles to directly induce T cell activation. Furthermore, we found that B-cell activation, antibody production, cytokine secretion and antigen cross-presentation were TLR2-MyD88 pathway dependent. Taken together, the present studies demonstrated that tumor-derived autophagosomes (DRibbles) efficiently induced B cells activation, antibody production, cytokine secretion and antigen cross-presentation mainly depending on their protein component via TLR2/MyD88 dependent manner. 相似文献
169.
IGFBP3, a Transcriptional Target of Homeobox D10, Is Correlated with the Prognosis of Gastric Cancer
Meng Xue Yanfei Fang Guoming Sun Wei Zhuo Jing Zhong Cuijuan Qian Lan Wang Liangjing Wang Jianmin Si Shujie Chen 《PloS one》2013,8(12)
Homeobox D10 (HoxD10) plays important roles in the differentiation of embryonic cells and progression of breast cancer. Our previous report revealed that insulin-like growth factor binding protein-3 (IGFBP3) was regulated by HoxD10 in gastric cancer cells; however, the functional roles and underlying mechanisms of IGFBP3 in gastric cancer remain unclear. Here, we found that the expression of IGFBP3 were upregulated after ectopic expression of HoxD10 in gastric cancer cells. Chromatin immunoprecipitation assay showed that HoxD10 bound to three potential regions of IGFBP3 promoter. Exogenous HoxD10 significantly enhanced the activity of luciferase reporter containing these binding regions in gastric cancer cells. Further data showed that all of these binding sites had Hox binding element “TTAT”. Immunohistochemical staining results revealed that IGFBP3 expression was significantly downregulated in 86 gastric adenocarcinomas tissues relative to their adjacent non-cancerous tissues (p<0.001). Moreover, IGFBP3 expression was significantly lower in gastric tumor with lymph node metastasis compared with that without lymph node metastasis (p=0.045). Patients with high expression level of IGFBP3 showed favorable 5 year overall survival (p=0.011). Knockdown of IGFBP3 accelerated gastric cancer cell migration and invasion and induced the expression of invasive factors including MMP14, uPA and uPAR. Thus, our data suggest that HoxD10-targeted gene IGFBP3 may suppress gastric cancer cell invasion and favors the survival of gastric cancer patients. 相似文献
170.
Xiang Mao Yin Li Shasha Zhao Jian Zhang Qian Lei Dandan Meng Fengyun Ma Wei Hu Mingjie Chen Junli Chang Yuesheng Wang Guangxiao Yang Guangyuan He 《PloS one》2013,8(10)
Seed storage proteins in wheat endosperm, particularly high-molecular-weight glutenin subunits (HMW-GS), are primary determinants of dough properties, and affect both end-use quality and grain utilization of wheat (Triticum aestivum L). In order to investigate the interactive effects between the transgenically overexpressed 1Ax1 subunit with different HMW-GS on dough quality traits, we developed a set of 8 introgression lines (ILs) overexpressing the transgenic HMW-glutenin subunit 1Ax1 by introgression of this transgene from transgenic line B102-1-2/1 into an elite Chinese wheat variety Chuanmai107 (C107), using conventional crossing and backcrossing breeding technique. The donor C107 strain lacks 1Ax1 but contains the HMW-GS pairs 1Dx2+1Dy12 and 1Bx7+1By9. The resultant ILs showed robust and stable expression of 1Ax1 even after five generations of self-pollination, and crossing/backcrossing three times. In addition, overexpression of 1Ax1 was compensated by the endogenous gluten proteins. All ILs exhibited superior agronomic performance when compared to the transgenic parent line, B102-1-2/1. Mixograph results demonstrated that overexpressed 1Ax1 significantly improved dough strength, resistance to extension and over-mixing tolerance, in the targeted wheat cultivar C107. Further, comparisons among the ILs showed the interactive effects of endogenous subunits on dough properties when 1Ax1 was overexpressed: subunit pair 17+18 contributed to increased over-mixing tolerance of the dough; expression of the Glu-D1 allele maintained an appropriate balance between x-type and y-type subunits and thereby improved dough quality. It is consistent with ILs C4 (HMW-GS are 1, 17+18, 2+12) had the highest gluten index and Zeleny sedimentation value. This study demonstrates that wheat quality could be improved by using transgenic wheat overexpressing HMW-GS and the feasibility of using such transgenic lines in wheat quality breeding programs. 相似文献