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951.
Xiao Sun Wen Zhou Hao Liu Aijun Zhang Chao-Ren Ai Shuang-Shuang Zhou Chang-Xiang Zhou Man-Qun Wang 《PloS one》2013,8(11)
Background
Transgenic Bt rice line T2A-1 expresses a synthesized cry2A gene that shows high resistance to Lepidoptera pests, including Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Pyralidae). Plant volatile orientation cues and the physical characteristics of the leaf surface play key roles in host location or host-plant acceptance of phytophagous insects. These volatile compounds and physical traits may become altered in Bt rice and it is not known whether this influences the behavior of C. medinalis when searching for oviposition sites.Results
The results of electronic nose analysis showed that the Radar map of Bt rice cultivars was analogous to the non- Bt rice cultivars at each growing stage. PCA analysis was able to partly discriminate between some of the Bt vs. non-Bt rice sensors, but could not to separate Bt cultivars from non-Bt cultivars. The total ion chromatogram between Bt and non-Bt rice cultivars at the seedling, booting and tillering stages were similar and 25 main compounds were identified by GC-MS. For most compounds, there was no significant difference in compound quantities between Bt and non-Bt rice cultivars at equivalent growth stages. The densities of the tubercle papicles and the trichomes on the upper and lower surfaces were statistically equal in Bt and non-Bt rice. The target pest, C. medinalis, was attracted to host rice plants, but it could not distinguish between the transgenic and the isogenic rice lines.Conclusions
There were no significant differences between the Bt rice line, T2A-1 and the non-Bt rice for volatiles produced or in its physical characteristics and there were no negative impacts on C. medinalis oviposition behavior. These results add to the mounting evidence that Bt rice has no negative impact on the target insect oviposition behavior. 相似文献952.
Objective
To determine the pathogenesis of a patient born with congenital heart defects, who had appeared normal in prenatal screening.Methods
In routine prenatal screening, G-banding was performed to analyse the karyotypes of the family and fluorescence in situ hybridization was used to investigate the 22q11.2 deletion in the fetus. After birth, the child was found to be suffering from heart defects by transthoracic echocardiography. In the following study, sequencing was used to search for potential mutations in pivotal genes. SNP-array was employed for fine mapping of the aberrant region and quantitative real-time PCR was used to confirm the results. Furthermore, other patients with a similar phenotype were screened for the same genetic variations. To compare with a control, these variations were also assessed in the general population.Results
The child and his mother each had a region that was deleted in the beta-defensin repeats, which are usually duplicated in the general population. Besides, the child carried a SOX7-gene duplication. While this duplication was not detected in his mother, it was found in two other patients with cardiac defects who also had the similar deletion in the beta-defensin repeats.Conclusion
The congenital heart defects of the child were probably caused by a SOX7-gene duplication, which may be a consequence of the partial haplotype of beta-defensin regions at 8p23.1. To our knowledge, this is the first congenital heart defect case found to have the haplotype of beta-defensin and the duplication of SOX7. 相似文献953.
Jing Qian Huaizhou You Qiuyu Zhu Shuai Ma Ying Zhou Ying Zheng Junfeng Liu Dingwei Kuang Yong Gu Chuanming Hao Feng Ding 《PloS one》2013,8(11)
Background
To examine the characteristics of oxidative stress in patients with acute kidney injury (AKI) and investigate the association between plasma nitrotyrosine levels and 90-day mortality in patients with AKI.Methodology/Principal Findings
158 patients with hospital-acquired AKI were recruited to this prospective cohort study according to RIFLE (Risk, Injury, Failure, Lost or End Stage Kidney) criteria. Twelve critically ill patients without AKI and 15 age and gender-matched healthy subjects served as control. Plasma 3-nitrotyrosine was analyzed in relation to 90-day all cause mortality of patients with AKI. The patients with AKI were followed up for 90 days and grouped according to median plasma 3-nitrotyrosine concentrations. Highest 3-NT/Tyr was detected in patients with AKI compared with healthy subjects, and critically ill patients without AKI (ANOVA p<0.001). The 90-day survival curves of patients with high 3-NT/Tyr showed significant differences compared with the curves of individuals with low 3-NT/Tyr (p = 0.001 by log rank test). Multivariate analysis (Cox regression) revealed that 3-NT/Tyr (p = 0.025) was independently associated with mortality after adjustment for age, gender, sepsis and Acute Physiology and Chronic Health Evaluation (APACHE) II score.Conclusions/Significance
There is excess plasma protein oxidation in patients with AKI, as evidenced by increased nitrotyrosine content. 3-NT/Tyr level was associated with mortality of AKI patients independent of the severity of illness. 相似文献954.
955.
Feng Lan Andrew S. Lee Ping Liang Veronica Sanchez-Freire Patricia K. Nguyen Li Wang Leng Han Michelle Yen Yongming Wang Ning Sun Oscar J. Abilez Shijun Hu Antje D. Ebert Enrique G. Navarrete Chelsey S. Simmons Matthew Wheeler Beth Pruitt Richard Lewis Joseph C. Wu 《Cell Stem Cell》2013,12(1):101-113
956.
957.
The objective of this study was to characterize the changes in lignin structure during hydrothermal pretreatment of shrub Tamarix ramosissima. Lignins in residual wood meal were isolated with alkaline ethanol solution and recovered with acid precipitation. A comparison between the recovered lignin fractions with milled wood lignin has been made in terms of yield, purity, gel permeation chromatography, Fourier transform infrared spectroscopy, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 1D 13C and 2D heteronuclear single quantum coherence nuclear magnetic resonance (HSQC NMR) spectroscopic techniques. Semiquantitative HSQC NMR showed that the relative amounts of β-O-4′ (around 76 % side chains) and resinol type substructures (16 %) of lignins were significantly modified during hydrothermal pretreatment. Py-GC/MS analyses brought direct evidences of these lignin samples with high S/G ratios ranging from 1.7 to 2.6. Moreover, the results indicated that an increase in the severity of the hydrothermal pretreatment enhanced the degradation of lignin unit side chains and the condensation of lignin and decreased the molecular weight of the recovered lignin fractions. This study demonstrated that the combination of autohydrolysis and alkaline ethanol process could potentially turn the recovered lignin fractions into value added products being in accordance with the “biorefinery” concept. 相似文献
958.
Bo-Mi Hwang Hee Suk Chae Young-Ju Jeong Young-Rae Lee Eun-Mi Noh Hyun Zo Youn Sung Hoo Jung Hong-Nu Yu Eun Yong Chung Jong-Suk Kim 《BMB reports》2013,46(11):533-538
The expression of matrix metalloproteinases (MMPs) produced by cancer cells has been associated with the high potential of metastasis in several human carcinomas, including breast cancer. Several pieces of evidence demonstrate that protein tyrosine phosphatases (PTP) have functions that promote cell migration and metastasis in breast cancer. We analyzed whether PTP inhibitor might control breast cancer invasion through MMP expression. Herein, we investigate the effect of 4-hydroxy-3,3-dimethyl-2H benzo[g]indole-2,5(3H)-dione (BVT948), a novel PTP inhibitor, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. The expression of MMP-9 and cell invasion increased after TPA treatment, whereas TPA-induced MMP-9 expression and cell invasion were decreased by BVT948 pretreatment. Also, BVT948 suppressed NF-κB activation in TPA-treated MCF-7 cells. However, BVT948 didn’t block TPA-induced AP-1 activation in MCF-7 cells. Our results suggest that the PTP inhibitor blocks breast cancer invasion via suppression of the expression of MMP-9. [BMB Reports 2013; 46(11): 533-538] 相似文献
959.
Eunjung Lee Ki-Woong Jeong Areum Shin Bonghwan Jin Hum Nath Jnawali Bong-Hyun Jun Jee-Young Lee Yong-Seok Heo Yangmee Kim 《BMB reports》2013,46(12):594-599
The anti-inflammatory activity of eriodictyol and its mode of action were investigated. Eriodictyol suppressed tumor necrosis factor (mTNF)-α, inducible nitric oxide synthase (miNOS), interleukin (mIL)-6, macrophage inflammatory protein (mMIP)-1, and mMIP-2 cytokine release in LPS-stimulated macrophages. We found that the anti-inflammatory cascade of eriodictyol is mediated through the Toll-like Receptor (TLR)4/CD14, p38 mitogen-activated protein kinases (MAPK), extracellular-signalregulated kinase (ERK), Jun-N terminal kinase (JNK), and cyclooxygenase (COX)-2 pathway. Fluorescence quenching and saturation-transfer difference (STD) NMR experiments showed that eriodictyol exhibits good binding affinity to JNK, 8.79 × 105 M-1. Based on a docking study, we propose a model of eriodictyol and JNK binding, in which eriodictyol forms 3 hydrogen bonds with the side chains of Lys55, Met111, and Asp169 in JNK, and in which the hydroxyl groups of the B ring play key roles in binding interactions with JNK. Therefore, eriodictyol may be a potent anti-inflammatory inhibitor of JNK. [BMB Reports 2013; 46(12): 594-599] 相似文献
960.