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81.
Gene flow from transgenic plants to compatible wild relatives is one of the major impediments to the development of the culture
of genetically engineered crop plants. In this work, the flow of EPSPS (conferring resistance to glyphosate) gene of transgene Brassica napus toward the untransgene B. napus and wild relative species Orychophragmus violaceus in an open field (1 ha) was studied. The data related to only the 2004 and 2005 autumn season on one location of southwest
of China. Pollen dispersal and fertilization of the target plants were favored and a detailed analysis of the hybrid offspring
was performed. In field, the data studied show that the gene flow frequency was 0.16% between GM and non-GM B. napus at a distance of 1 m from the transgenic donor area. The crosspollination frequency was 0.05% between GM and non-GM B. napus at a distance of 5 m from the transgenic donor area. At a distance of 10 m, no crosspollination was observed. According to
the results of this study, B. napus transgene flow was low. However, the wild relative species O. violaceus could not be fertilized by the transgenic pollen of B. napus, no matter what the distance was. 相似文献
82.
Background
Nosocomial infection (NI) causes prolonged hospital stays, increased healthcare costs, and higher mortality among patients with hematological malignancies (HM). However, few studies have compared the incidence of NI according to the HM lineage.Objective
To compare the incidence of NI according to the type of HM lineage, and identify the risk factors for NI.Methods
This prospective observational study monitored adult patients with HM admitted for >48 hours to the General Hospital of the People''s Liberation Army during 2010–2013. Attack rates and incidences of NI were compared, and multivariable logistic regression was used to control for confounding effects.Results
This study included 6,613 admissions from 1,922 patients. During these admissions, 1,023 acquired 1,136 NI episodes, with an attack rate of 15.47% and incidence of 9.6‰ (95% CI: 9.1–10.2). Higher rates and densities of NIs were observed among myeloid neoplasm (MN) admissions, compared to lymphoid neoplasm (LN) admissions (28.42% vs. 11.00%, P<0.001 and 11.4% vs. 8.4‰, P<0.001). NI attack rates in acute myeloid leukemia (AML) and myelodysplastic/myeloproliferative neoplasm (MDS/MPN) were higher than those in MDS (30.69% vs. 20.19%, P<0.001; 38.89% vs. 20.19%, P = 0.003). Attack rates in T/NK-cell neoplasm and B-cell neoplasm were higher than those in Hodgkin lymphoma (15.04% vs. 3.65%; 10.94% vs. 3.65%, P<0.001). Multivariable regression analysis indicated prolonged hospitalization, presence of central venous catheterization, neutropenia, current stem cell transplant, infection on admission, and old age were independently associated with higher NI incidence. After adjusting for these factors, MN admissions still had a higher risk of infection (odds ratio 1.34, 95% CI: 1.13–1.59, P<0.001).Conclusion
Different NI attack rates were observed for HM from different lineages, with MN lineages having a higher attack rate and incidence than LN lineages. Special attention should be paid to MN admissions, especially AML and MDS/MPN admissions, to control NI incidence. 相似文献83.
XF Wang XT Tian E Ohkoshi B Qin YN Liu PC Wu MJ Hour HY Hung K Qian R Huang KF Bastow WP Janzen J Jin SL Morris-Natschke KH Lee L Xie 《Bioorganic & medicinal chemistry letters》2012,22(19):6224-6228
Based on a shared structural core of diarylamine in several known anticancer drugs as well as a new cytotoxic hit 6-chloro-2-(4-cyanophenyl)amino-3-nitropyridine (7), 30 diarylamines and diarylethers were designed, synthesized, and evaluated for cytotoxic activity against A549, KB, KB-vin, and DU145 human tumor cell lines (HTCL). Four new leads 11e, 12, 13a, and 13b were discovered with GI(50) values ranging from 0.33 to 3.45μM. Preliminary SAR results revealed that a diarylamine or diarylether could serve as an active structural core, meta-chloro and ortho-nitro groups on the A-ring (either pyridine or phenyl ring) were necessary and crucial for cytotoxic activity, and the para-substituents on the other phenyl ring (B-ring) were related to inhibitory selectivity for different tumor cells. In an investigation of potential biological targets of the new leads, high thoughput kinase screening discovered that new leads 11e, 12 and 13b especially inhibit Mer tyrosine kinase, a proto-oncogene associated with munerous tumor types, with IC(50) values of 2.2-3.0μM. Therefore, these findings provide a good starting point to optimize a new class of compounds as potential anticancer agents, particularly targeting Mer tyrosine kinase. 相似文献
84.
Zhuang Jin Hua Lin Sathish Srinivasan Jerome C. Nwachukwu Nelson Bruno Patrick R. Griffin Kendall W. Nettles Theodore M. Kamenecka 《Bioorganic & medicinal chemistry letters》2017,27(2):347-353
Adverse effects of glucocorticoids could be limited by developing new compounds that selectively modulate anti-inflammatory activity of the glucocorticoid receptor (GR). We have synthesized a novel series of steroidal GR ligands, including potent agonists, partial agonists and antagonists with a wide range of effects on inhibiting secretion of interleukin-6. Some of these new ligands were designed to directly impact conformational stability of helix-12, in the GR ligand-binding domain (LBD). These compounds modulated GR activity and glucocorticoid-induced gene expression in a manner that was inversely correlated to the degree of inflammatory response. In contrast, compounds designed to directly modulate LBD epitopes outside helix-12, led to dissociated levels of GR-mediated gene expression and inflammatory response. Therefore, these new series of compounds and their derivatives will be useful to dissect the ligand-dependent features of GR signaling specificity. 相似文献
85.
A series of single isomers tetrahydro‐β‐carboline diketopiperazines were stereoselectively synthesized starting from l ‐tryptophan methyl ester hydrochloride and six aldehydes through a four‐step reaction including Pictet‐Spengler reaction, crystallization‐induced asymmetric transformations (CIAT), Schotten‐Baumann reaction, and intramolecular ester amidation. The chemical structures were characterized by nuclear magnetic resonance (NMR) and elemental analysis, among which two compounds were determined by x‐ray single crystal diffraction. Moreover, antimicrobial activities of all the compounds were also tested. Chirality 25:656–662, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
86.
87.
RAGE mediates amyloid-beta peptide transport across the blood-brain barrier and accumulation in brain 总被引:21,自引:0,他引:21
Deane R Du Yan S Submamaryan RK LaRue B Jovanovic S Hogg E Welch D Manness L Lin C Yu J Zhu H Ghiso J Frangione B Stern A Schmidt AM Armstrong DL Arnold B Liliensiek B Nawroth P Hofman F Kindy M Stern D Zlokovic B 《Nature medicine》2003,9(7):907-913
Amyloid-beta peptide (Abeta) interacts with the vasculature to influence Abeta levels in the brain and cerebral blood flow, providing a means of amplifying the Abeta-induced cellular stress underlying neuronal dysfunction and dementia. Systemic Abeta infusion and studies in genetically manipulated mice show that Abeta interaction with receptor for advanced glycation end products (RAGE)-bearing cells in the vessel wall results in transport of Abeta across the blood-brain barrier (BBB) and expression of proinflammatory cytokines and endothelin-1 (ET-1), the latter mediating Abeta-induced vasoconstriction. Inhibition of RAGE-ligand interaction suppresses accumulation of Abeta in brain parenchyma in a mouse transgenic model. These findings suggest that vascular RAGE is a target for inhibiting pathogenic consequences of Abeta-vascular interactions, including development of cerebral amyloidosis. 相似文献
88.
贵州东部寒武纪的杷榔组发育,化石丰富,含有杷榔动物群;其中掘头虫类、莱德利基虫类三叶虫保存好,序列完整,提供了研究这些类群属种个体发育的重要材料。本文据杷榔组Redlichia (Pteroredlichia) chinensis(Walcott,1905)的300多块标本的分析数据,详细讨论和重点研究了其从幼虫期、分节期至成虫期个体发育特征,分析各个阶段的形态变化及个体发育演化趋势。丰富了R.(Pteroredlichia) chinensis个体发育的资料,对莱德利基虫属种厘定起到积极的作用,提供了属种分类对比的重要证据。 相似文献
89.
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
90.
Inducible nitric oxide synthase (iNOS) is responsible for nitric oxide (NO) synthesis from l-arginine in response to inflammatory mediators. It is reported that iNOS is degraded mainly by the ubiquitin-proteasome pathway in RAW264.7 cells and human embryonic kidney (HEK) 293 cells. In this study, we showed that iNOS was ubiquitinated and degraded dependent on CHIP (COOH terminus of heat shock protein 70-interacting protein), a chaperone-dependent ubiquitin ligase. The results from overexpression and RNAi experiments demonstrated that CHIP decreased the protein level of iNOS, shortened the half-life of iNOS and attenuated the production of NO. Furthermore, CHIP promoted ubiquitination and proteasomal degradation of iNOS by associating with iNOS. These results suggest that CHIP plays an important role in regulation iNOS activity. 相似文献