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81.
Wen-Jie Mu Wen-Jing Zhong Ji-Yi Yao Lu-Jing Li Yu-lan Peng Yi Wang Li-sha Liu Ying Xiao Shou-jun Liu Chang-jun Wu Yu-xin Jiang Shyam Sundar Parajuly Ping Xu Yi Hao Jing Li Bao-Ming Luo Hui Zhi 《PloS one》2016,11(2)
Background
This study aimed to confirm whether strain ratio should be added after evaluation of lesions with 5-point elasticity scoring for differentiating benign and malignant breast lesions on ultrasonographic elastography(UE).Materials and Methods
From June 2010 to March 2012, 1080 consecutive female patients with breast lesions were recruited into a multicenter retrospective study, which involved 8 centers across China. Each institutional ethic review board approved the study, and all the patients gave written informed consent. All the patients underwent the UE procedure and the strain ratios were calculated and the final diagnosis was made by histological findings. The sensitivity, specificity, accuracy, PPV and NPV were calculated for each of the two evaluation systems and the areas under the ROC curve were compared.Results
The strain ratios of benign lesions (mean, 2.6±2.0) and malignant lesions (mean,7.9±5.8) were significantly different (p <0.01). When the cutoff point was 3.01, strain ratio method had 79.8% sensitivity, 82.8% specificity, and 81.3% accuracy, while the 5-point scoring method had 93.1% sensitivity, 73.0% specificity, and 76.8% accuracy. The areas under the ROC curve with the strain ratio method and 5-point scoring method were 0.863 and 0.865, respectively(p>0.05). The strain ratio method shows better a diagnosis performance of the lesions with elasticity score 3 and 4.Conclusions
Although the two UE methods have similar diagnostic performance, separate calculation of the strain ratios seems compulsory, especially for the large solid breast lesions and the lesions with elasticity score 3 and 4. 相似文献82.
Rongzhong Huang Hongchang Gao Lihua Ma Xiao Wang Jianmin Jia Mingju Wang Liang Zhang Xia Liu Peng Zheng Liu Yang Lei Yang Li Dan Xie Peng 《Metabolomics : Official journal of the Metabolomic Society》2014,10(1):33-41
Herpes simplex virus type 1 (HSV-1) is a large, neurotropic, double-stranded DNA virus that establishes a lifelong latent infection in neurons and glial cells. Previous studies reveal that several metabolic perturbations are associated with HSV-1 infection. However, the extracellular metabolic alterations associated with HSV-1 infection have not been systematically profiled in human cells. Here, a proton nuclear magnetic resonance-based metabonomic approach was applied to differentiate the extracellular metabonomic profiles of HSV-1 infected human oligodendroglia cells (n = 18) and matched control cells (n = 18) at three time points (12, 24, and 36 h post-infection). Resulting spectra were analyzed by chemometric and statistical methods. Metabonomic profiling revealed perturbations in 21 extracellular metabolites. Partial least squares discriminant analysis demonstrated that the whole metabolic patterns enabled statistical discrimination between HSV-1 infected human oligodendroglia cells and control cells. Eight extracellular metabolites, seven of which were amino acids, were primarily responsible for score plot discrimination between HSV-1 infected human oligodendroglia cells and control cells at 36 h post-infection: alanine, glycine, isoleucine, leucine, glutamate, glutamine, histidine, and lactate. HSV-1 infection alters amino acid metabolism in human oligodendroglia cells cultured in vitro. HSV-1 infection may disturb these host cellular pathways to support viral replication. Through elucidating the extracellular metabolic changes incident to HSV-1 infection, this study also provides future directions for investigation into the pathogenic mechanism of HSV-1. 相似文献
83.
Induction of multiple cytotoxic T lymphocyte responses in mice by a multiepitope DNA vaccine against dengue virus serotype 1 下载免费PDF全文
Xin Yu Chen De Zhou Li Xiao Zhi Zhong Bokun Chen Zhi Liang Duan Jin Sheng Wen 《Microbiology and immunology》2016,60(12):835-845
84.
Efficient somatic embryogenesis (SE) and in vitro flowering and fruiting were achieved in Saposhnikovia divaricata (Turcz.) Schischk. Friable embryogenic callus developed from the root, internode, and leaf explants on Murashige and Skoog
medium (MS) with 2.26 μM 2,4-dichlorophenoxyacetic acid (2,4-D), and subsequently developed into somatic embryos on MS medium
containing 4–5% sucrose, 1.74 μM naphthaleneacetic acid (NAA), 4.44 μM 6-benzylaminopurine (BA), and 1.90 μM abscisic acid
(ABA). Then the mature embryos were separated and transferred onto MS with 3% sucrose and 0.6% agar for further development
and conversion to plantlets. In vitro flowering and fruiting were obtained when the subcultures were carried out for over
15 months. Paclobutrazol (PP333) or ethephon (ETH) at low levels promoted flowering significantly. Also, abnormal rootless
somatic embryos of S. divaricata could form flowers and fruits in vitro. 相似文献
85.
Optimized production of high-titer recombinant adeno-associated virus in roller bottles 总被引:6,自引:0,他引:6
Liu YL Wagner K Robinson N Sabatino D Margaritis P Xiao W Herzog RW 《BioTechniques》2003,34(1):184-189
Adeno-associated viral (AAV) vectors are used for in vivo gene transfer in a number of preclinical models of genetic diseases (including large-animal models) and are currently being tested in clinical trials for treatment of hemophilia B and cystic fibrosis. Protocols for production of AAV vectors in a helper virus-free system are available and are based on transient transfection of HEK-293 cells with multiple plasmids. Scale-up of vector production has been labor intensive and inefficient because of a lack of larger culture vessels suitable for growth of adherent cells, large-scale transfection, and vector production. Here we report efficient production of AAV vector in roller bottles, which represents a 10-fold scale-up from the conventional flask or plate method. Optimized production yielded greater than 10(13) vector genomes per bottle and was as cost effective as published protocols using plates. Successful vector production by this method was dependent on optimization of transfection by calcium phosphate precipitation, of monitoring of cell growth (by measurement of glucose consumption), of cell culture conditions, and CO2/air exchange with the culture vessel. 相似文献
86.
Strategies for identifying genetic risk factors in complex diseases by association studies require the comparison of allele frequencies of numerous SNPs between affected and control populations. Theoretically, hundreds of thousands of SNP markers across the genome will have to be genotyped in these studies. Genotyping SNPs one sample at a time is extremely costly and time consuming. To streamline whole genome association studies, some have proposed to screen SNPs by pooling the DNA samples initially for allele frequency determination and perform individual genotyping only when there is a significant discrepancy in allele frequencies between the affected and control populations. Here we describe a new method for determining the allele frequency of SNPs in pooled DNA samples using a two-color primer extension assay with real-time monitoring of fluorescence polarization (named kinetic FP-TDI assay). By comparing the ratio of the rate of incorporation of the two allele-specific dye-terminators, one can calculate the relative amounts of each allele in the pooled sample. The accuracy of allele frequency determination with pooled samples is within 3.3 +/- 0.8% of that determined by genotyping individual samples that make up the pool. 相似文献
87.
Young Ho Lee Jason N. Zimmerman William Custodio Yizhi Xiao Tayebeh Basiri Sahza Hatibovic-Kofman Walter L. Siqueira 《PloS one》2013,8(7)
Acquired enamel pellicle (AEP) is a protein film that forms on the enamel surface of teeth by selective adsorption of proteins and peptides present in the mouth. This protein film forms the interface between enamel and the damage oral biofilm, which modulates the attachment of bacteria found in oral biofilm. The overall goal of this study was to gain insight into the biological formation of the human in vivo AEP. This study hypothesized that AEP is created by the formation of successive protein layers, which consist of initial binding to enamel and subsequent protein-protein interactions. This hypothesis was examined by observing quantitative and qualitative changes in pellicle composition during the first two hours of AEP formation in the oral cavity. Quantitative mass spectrometry approaches were used to generate an AEP protein profile for each time-point studied. Relative proteomic quantification was carried out for the 50 proteins observed in all four time-points. Notably, the abundance of important salivary proteins, such as histatin 1, decrease with increasing of the AEP formation, while other essential proteins such as statherin showed constant relative abundance in all time-points. In summary, this is the first study that investigates the dynamic process to the AEP formation by using proteomic approaches. Our data demonstrated that there are significant qualitative and quantitative proteome changes during the AEP formation, which in turn will likely impact the development of oral biofilms. 相似文献
88.
89.
Seema Sharma Haiyan Zheng Yuanpeng J. Huang Asli Ertekin Yoshitomo Hamuro Paolo Rossi Roberto Tejero Thomas B. Acton Rong Xiao Mei Jiang Li Zhao Li‐Chung Ma G. V. T. Swapna James M. Aramini Gaetano T. Montelione 《Proteins》2009,76(4):882-894
Disordered or unstructured regions of proteins, while often very important biologically, can pose significant challenges for resonance assignment and three‐dimensional structure determination of the ordered regions of proteins by NMR methods. In this article, we demonstrate the application of 1H/2H exchange mass spectrometry (DXMS) for the rapid identification of disordered segments of proteins and design of protein constructs that are more suitable for structural analysis by NMR. In this benchmark study, DXMS is applied to five NMR protein targets chosen from the Northeast Structural Genomics project. These data were then used to design optimized constructs for three partially disordered proteins. Truncated proteins obtained by deletion of disordered N‐ and C‐terminal tails were evaluated using 1H‐15N HSQC and 1H‐15N heteronuclear NOE NMR experiments to assess their structural integrity. These constructs provide significantly improved NMR spectra, with minimal structural perturbations to the ordered regions of the protein structure. As a representative example, we compare the solution structures of the full length and DXMS‐based truncated construct for a 77‐residue partially disordered DUF896 family protein YnzC from Bacillus subtilis, where deletion of the disordered residues (ca. 40% of the protein) does not affect the native structure. In addition, we demonstrate that throughput of the DXMS process can be increased by analyzing mixtures of up to four proteins without reducing the sequence coverage for each protein. Our results demonstrate that DXMS can serve as a central component of a process for optimizing protein constructs for NMR structure determination. Proteins 2009. © 2009 Wiley‐Liss, Inc. 相似文献
90.