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201.
Yanli Zhang Lina Wang Wenhao Zhou Huijun Wang Jin Zhang Shanshan Deng Weihua Li Huawei Li Zuohua Mao Duan Ma 《Developmental biology》2013
Tissue factor pathway inhibitor-2 (Tfpi-2) is an important serine protease inhibitor in the extracellular matrix (ECM), but its precise physiological significance remains unknown. This work is part of a series of studies intended to investigate functional roles of Tfpi-2 and explore the underlying molecular mechanisms. First, we cloned and identified zebrafish Tfpi-2 (zTfpi-2) as an evolutionarily conserved protein essential for zebrafish development. We also demonstrated that ztfpi-2 is mainly expressed in the central nervous system (CNS) of zebrafish, and embryonic depletion of ztfpi-2 caused severe CNS defects. In addition, changes of neural markers, including pax2a, egr2b, huC, ngn1, gfap and olig2, confirmed the presence of developmental abnormalities in the relevant regions of ztfpi-2 morphants. Using microarray analysis, we found that members of the Notch pathway, especially her4 and mib, which mediate lateral inhibition in CNS development, were also downregulated. Intriguingly, both her4 and mib were able to partially rescue the ztfpi-2 morphant phenotype. Furthermore, Morpholino knockdown of ztfpi-2 resulted in upregulation of neuronal markers while downregulation of glial markers, providing evidence that the Notch pathway is probably involved in ztfpi-2-mediated CNS development. 相似文献
202.
【目的】探讨新城疫病毒(Newcastle disease virus,NDV)基质(matrix,M)蛋白和禽细胞核磷蛋白B23.1在HEK-293T细胞中的相互作用。【方法】分别参照GenBank中NDV JS/5/05/Go株全基因序列(JN631747)和禽细胞核磷蛋白B23.1基因序列(NM205267),设计、合成扩增M基因和B23.1基因的引物,利用RT-PCR扩增出M基因和DF1细胞的B23.1基因,分别克隆至真核表达载体获得重组表达质粒pEGFP-M、pCMV-HA-M和pDsRed-B23.1;将pEGFP-M和pDsRed-B23.1共转染HEK-293T细胞,利用荧光显微镜观察M蛋白与B23.1蛋白的共定位;利用免疫共沉淀(Co-IP)技术进一步验证两种蛋白的相互作用。【结果】Western blot结果表明构建的重组质粒在转染的HEK-293T细胞中正确表达;荧光显微镜观察显示M蛋白与B23.1蛋白在核仁具有共定位特征;Co-IP进一步证实两者能发生相互作用。【结论】NDV M蛋白与禽细胞核磷蛋白B23.1存在相互作用,M蛋白可能通过与B23.1蛋白的相互作用进入核仁。 相似文献
203.
Lihui Wei Corinne Bensimon Julia Lockwood Xuxu Yan Pasan Fernando R. Glenn Wells Yin Duan Yong-Xiang Chen J. Russell Redshaw Peter A. Covitz Terrence D. Ruddy 《Bioorganic & medicinal chemistry》2013,21(11):2903-2911
Coronary artery disease (CAD) is a major cause of death in Canada and the United States. Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a useful diagnostic test in the management of patients with CAD. The widely used SPECT MPI agents, 99mTc sestamibi and 99mTc tetrofosmin, exhibit less than ideal pharmacokinetic properties with decreasing uptake with higher flows. 123I has a similar energy as 99mTc, an ideal half life, and is readily available from cyclotrons. The objective of this study was to develop an 123I labeled MPI agent based on rotenone, a mitochondrial complex I inhibitor, as an alternative to currently available SPECT MPI agents. Methods: 123I-CMICE-013 was synthesized by radiolabeling rotenone with 123I in trifluoroacetic acid (TFA) with iodogen as the oxidizing agent at 60 °C for 45 min, followed by RP-HPLC purification. The product was formulated in 5% EtOH in 10 mM NaOAc pH 6.5. The inactive analog 127I-CMICE-013 was isolated and characterized by NMR and mass spectrometry, and the structure determined. Micro-SPECT imaging studies were carried out in normal and infarcted rats. Biodistribution studies were performed in normal rats at 2 h (n = 6) and 24 h (n = 8) post injection (p.i.). Results: 123I-CMICE-013 was isolated with >95% radiochemical purity and high specific activity (14.8–111 GBq/μmol; 400–3000 mCi/μmol). Structural analysis showed that rotenone was iodinated at 7′-position, with removal of the 6′,7′-double bond, and addition of a hydroxy group at 6′-position. MicroSPECT images in normal rats demonstrated homogeneous and sustained myocardial uptake with minimal interference from lung and liver. Absent myocardial perfusion was clearly identified in rats with permanent left coronary artery ligation and ischemia-reperfusion injury. In vivo biodistribution studies in normal rats at 2 h p.i. showed significant myocardial uptake (2.01 ± 0.48%ID/g) and high heart to liver (2.98 ± 0.93), heart to lung (4.11 ± 1.04) and heart to blood (8.37 ± 3.97) ratios. At 24 h p.i., the majority of 123I-CMICE-013 was cleared from tissues, and a significant amount of tracer was found in the thyroid, indicating in vivo deiodination of the tracer. Conclusion: 123I-CMICE-013 is a promising new radiotracer for SPECT MPI with high myocardial uptake, very good target to background ratios and favorable biodistribution characteristics. 相似文献
204.
目的观察腹腔注射米诺环素对改良Allen’s法造成的不完全脊髓损伤大鼠脊髓中脑源性神经营养因子以及神经营养因子3表达的影响,探讨米诺环素治疗脊髓损伤的作用机制。方法成年雌性Sprague-Dawley(SD)大鼠54只,改良Allen’s法造成不完全脊髓损伤,根据实验需要可以分为3组,空白组,只打开脊柱椎板,不损伤;治疗组,大鼠脊髓损伤,并腹腔注射米诺环素;损伤组,大鼠脊髓损伤,腹腔注射等剂量的生理盐水。观察各组大鼠的后肢能力Basso-Beattie-Bresnahan评分,并于不同时段(3d、7d,14d)取大鼠脊髓T8-9段采用逆转录PCR,以及免疫化学组织染色法测定脑源性神经营养因子以及神经营养因子3的表达。结果米诺环素能够明显改善不完全脊髓损伤大鼠的功能,逆转录PCR和脊髓组织冰冻切片免疫组织化学染色DAB都能证实米诺环素治疗组脑源性神经营养因子以及神经营养因子3表达显著增多。结论米诺环素在治疗不完全脊髓损伤大鼠的机制还应与其上调了大鼠体内的脑源性神经营养因子以及神经营养因子3表达有关。 相似文献
205.
Fungi were isolated from Meloidogyne spp. eggs and females on 102 field-collected root samples in China. Of the 235 fungi isolated (representing 18 genera and 26 species), the predominant fungi were Fusarium spp. (42.1% of the isolates collected), Fusarium oxysporum (13.2%), Paecilomyces lilacinus (12.8%), and Pochonia chlamydosporia (8.5%). The isolates were screened for their ability to parasitise Meloidogyne incognita eggs in 24-well tissue culture plates in two different tests. The percentage of eggs parasitised by the fungi, the numbers of unhatched eggs and alive and dead juveniles were counted at 4 and 7 days after inoculation. The most promising fungi included five Paecilomyces isolates, 10 Fusarium isolates, 10 Pochonia isolates and one Acremonium isolate in test 1 or test 2. Paecilomyces lilacinus YES-2 and P. chlamydosporia HDZ-9 selected from the in vitro tests were formulated in alginate pellets and evaluated for M. incognita control on tomato in a greenhouse by adding them into a soil with sand mixture at rates of 0.2, 0.4, 0.8 and 1.6% (w/w). P. lilacinus pellets at the highest rate (1.6%) reduced root galling by 66.7%. P. chlamydosporia pellets at the highest rate reduced the final nematode density by 90%. The results indicate that P. lilacinus and P. chlamydosporia as pellet formulation can effectively control root-knot nematodes. 相似文献
206.
Molecular and pathogenic characterization of new Xanthomonas oryzae pv. oryzae strains from the coastline region of Fangchenggang city in China 总被引:1,自引:0,他引:1
Shu-Qing Yang Shu-Yan Liu Shuai Zhao Yan-Hua Yu Rong-Bai Li Cheng-Jie Duan Ji-Liang Tang Jia-Xun Feng 《World journal of microbiology & biotechnology》2013,29(4):713-720
Virulence assays and DNA polymorphism analyses were used to characterize 33 Xanthomonas oryzae pv. oryzae (Xoo) strains collected from the coastline region of Fangchenggang city in China. Two new pathogenic races (FXP1 and FXP2), were determined by leaf-clipping inoculation of 12 near-isogenic International Rice-Bacterial Blight (IRBB) rice lines, each containing a single resistance gene. Race FXP1 consisted of twenty-eight strains that were incompatible on IRBB5 and IRBB7, while race FXP2 included five strains that were incompatible on IRBB5 and IRBB7 and moderately virulent on IRBB8 containing the xa8 gene. Restriction fragment length polymorphism (RFLP) analysis revealed that each probe of avrXa10 and IS1112 resolved two haplotypes. In a dendrogram generated from the combined RFLP data, the 33 Xoo strains were resolved into two clusters. There was a weak correlation (r = 0.53) between race and haplotype. All of the rice cultivars planted in the coastline region of Fangchenggang city were susceptible to the representative Xoo strains tested above. However, we found that four rice cultivars used as breeding materials in the laboratory could fully resist infection by the Xoo strains, suggesting that the isolated Xoo strains could be used to detect resistant rice cultivars suitable for planting in the local rice field. 相似文献
207.
Density-dependent responses of Picea purpurea seedlings for plant growth and resource allocation under elevated temperature 总被引:1,自引:0,他引:1
Jinchuang Wang Baoli Duan Yuanbin Zhang Mansoor Ahmed Bughio Wei Jia 《Trees - Structure and Function》2013,27(6):1775-1787
This study was conducted to determine whether plants in the presence or absence of competition differ in their responses to warming, and whether density modifies the effect of warming. Picea purourea seedlings were grown under ambient and warming (ambient +2.2 °C) conditions in climate control chambers with two different planting densities. After 4 years, seedlings were harvested and measured for height, stem diameter, leaf area, structural biomass, carbon, nitrogen, chlorophyll and carbohydrate levels of needles, branches, stem and roots. At low density, warming increased height, stem diameter, total leaf area biomass production and carbohydrate concentration per seedling, while it decreased C/N ratio for all plant parts, but did not affect chlorophyll content. By contrast, at high density, although warming increased biomass and total leaf area, it did not affect plant height and stem diameter. At the same time, it had different effects on chlorophyll content, C/N ratio and carbohydrate levels among plant parts. On the other hand, high density limited plant growth and altered resource allocation pattern. Our study demonstrates that planting densities decreased the temperature-induced growth enhancement of P. purpurea seedlings and the effects of warming on resource allocation not only showed density-dependence, but also vary with tissue age classes and root diameter; the responses of plants to elevated temperature, acquired from plants growing as individuals, may not be applicable to plants grown under intraspecific competition as typically found in the field. 相似文献
208.
Wenguang Fan Guicheng Huo Xiaomin Li Lijie Yang Cuicui Duan Tingting Wang Junliang Chen 《World journal of microbiology & biotechnology》2013,29(12):2365-2372
The gastrointestinal microbiota plays a crucial role in the health and disease of the host through its impact on nutrition. Gut microbial composition is related to different diets, but an association of microbiota with different diets in infant has not yet been shown. In this work, we compared the fecal microbiota of breast-fed (BF) and formula-fed infants (FF). By using Illumina high-throughput sequencing and biochemical analyses, we found differences in gut microbiota between the two groups. BF infants showed a significant enrichment of Actinobacteria and Firmicutes and depletion of Proteobacteria (P < 0.05), the abundance of Bacteroidetes in the two groups was very low (P > 0.05). Enterobacteriaceae (Proteobacteria) were the dominant bacteria in FF infant fecal microbiota, and Veillonellaceae (Firmicutes) and Enterobacteriaceae (Proteobacteria) were the dominant bacteria in the BF infant fecal microbiota. The number of genera (percentage of sequences >0.1 %) in BF and FF infants was 17 and 15 respectively, and Streptococcus was the dominant bacterial genus in both groups. 相似文献
209.
Bacterial cultures were enriched from sediments in Germany and Vietnam reductively dechlorinating hexachlorobenzene and the highly persistent 1,3,5-trichlorobenzene to monochlorobenzene. The main products of the reductive dechlorination of hexachlorobenzene were monochlorobenzene and dichlorobenzenes (1,2-; 1,3- and 1,4-dichlorobenzene) while no trichlorobenzenes accumulated. For the reductive dechlorination of 1,3,5-trichlorobenzene with the mixed culture from Vietnam sediment, 1,3- dichlorobenzene and monochlorobenzene were produced as intermediate and final end-product, respectively. The pattern of dechlorination did not change when the cultures were repeatedly exposed to oxygen over seven transfers demonstrating oxygen tolerance of the dechlorinating bacteria. However, reductive dechlorination of 1,3,5-trichlorobenzene was inhibited by vancomycin at a concentration of 5 mg L?1. Vancomycin delayed reductive dechlorination of hexachlorobenzene in mixed cultures by about 6 months. When repeatedly applied, vancomycin completely abolished the ability of the mixed culture to transform hexachlorobenzene. Sensitivity to vancomycin and insensitivity to brief exposure of oxygen indicates that the dechlorinating bacteria in the mixed cultures did not belong to the genus Dehalococcoides. 相似文献
210.