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71.
C反应蛋白(C-reaction protein,CRP)是反映机体炎症的有效标志物,早期检测是判断炎症相关疾病的关键,因此,研制CRP新型检测制剂具有重要意义。利用噬菌体表面展示技术对CRP特异性亲和配体进行了筛选,采用固相肽合成技术对目标配体进行了合成,并经生物标记、高效液相色谱法(high performance liquid chromatography,HPLC)分析及质谱(mass spectrometry,MS)鉴定,成功制得检测CRP的荧光探针。经3轮筛选、ELISA检测、重组噬菌体测序及序列比对后得到1个目标配体肽:S-P-H-N-R-S-N-L-V-Q-E-L;经肽合成及生物标记获得1种CRP荧光探针:FITC-(Acp)-S-P-H-N-R-S-N-L-V-Q-E-L。研究结果为CRP的有效检测提供了一种新型制剂。 相似文献
72.
Post-translational protein modification by the covalent conjugation of ubiquitin, originally implicated as a signal for proteolytic degradation by 26S proteasome, has now been realised to play important roles in the regulation of almost all biological processes in eukaryotes. In order to understand these processes in greater detail there is a requirement for techniques that can purify mixtures of ubiquitin-conjugated proteins, as a prerequisite to their identification and characterisation. Here we review the methods that have been applied to the bulk purification of ubiquitinated proteins and discuss their applications in proteomic analyses of the 'ubiquitome'. 相似文献
73.
摘要 目的:研究术前三叶因子1(TFF1)、热休克蛋白70(HSP70)、天冬氨酸-天冬酰胺β羟化酶(ASPH)与原发性肝癌(PHC)患者手术切除术后早期复发的关系。方法:选取2018年1月~2019年12月我院收治的83例PHC患者,均行手术切除治疗,术后均随访2年,根据是否复发分为复发组49例以及未复发组34例。比较两组术前TFF1、HSP70、ASPH水平差异,收集患者基线资料,采用多因素Logistic回归分析PHC患者手术切除术后早期复发的危险因素,采用受试者工作特征(ROC)曲线分析术前TFF1、HSP70、ASPH水平预测PHC患者手术切除术后早期复发的效能。结果:复发组术前TFF1、HSP70、ASPH水平均高于未复发组(P<0.05)。复发组肿瘤直径≥5 cm、肿瘤数目为多发、有血管侵犯的患者比例高于未复发组(P<0.05)。多因素Logistic回归分析结果显示:肿瘤直径≥5 cm、多发肿瘤、血管侵犯及术前TFF1、HSP70、ASPH高水平是PHC患者手术切除术后早期复发的危险因素(均OR>1,P<0.05)。ROC曲线分析结果显示:术前TFF1、HSP70、ASPH联合检测预测PHC患者手术切除术后早期复发的曲线下面积为0.815,明显高于上述三项指标单独检测的0.704、0.713、0.707。结论:术前TFF1、HSP70、ASPH与PHC患者手术切除术后早期复发密切相关,联合检测三项指标水平可能有助于预测PHC患者手术切除术后早期复发。 相似文献
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75.
Sylwia Struk Anse Jacobs Elena Snchez Martín‐Fontecha Kris Gevaert Pilar Cubas Sofie Goormachtig 《Plant, cell & environment》2019,42(2):387-409
Protein–protein interactions (PPIs) represent an essential aspect of plant systems biology. Identification of key protein players and their interaction networks provide crucial insights into the regulation of plant developmental processes and into interactions of plants with their environment. Despite the great advance in the methods for the discovery and validation of PPIs, still several challenges remain. First, the PPI networks are usually highly dynamic, and the in vivo interactions are often transient and difficult to detect. Therefore, the properties of the PPIs under study need to be considered to select the most suitable technique, because each has its own advantages and limitations. Second, besides knowledge on the interacting partners of a protein of interest, characteristics of the interaction, such as the spatial or temporal dynamics, are highly important. Hence, multiple approaches have to be combined to obtain a comprehensive view on the PPI network present in a cell. Here, we present the progress in commonly used methods to detect and validate PPIs in plants with a special emphasis on the PPI features assessed in each approach and how they were or can be used for the study of plant interactions with their environment. 相似文献
76.
The spatial extent of animal movement is a key consideration when designing conservation measures, such as marine protected areas. Methods to assess territory size in the marine environment, however, are labour intensive and/or expensive. Here, we explore a novel method to investigate the spatial ecology of territorial fishes by examining their reactions to an artificial light stimulus. During benthic towed video surveys conducted in Lyme Bay, southwest England, several species of wrasse (Labridae) have frequently been observed pursuing a laser projected onto the seabed. While the motivation behind ‘laser‐chasing’ is unclear, we quantified the spatial aspects of this behaviour by comparing chase distance and chase likelihood between and within species, to determine the potential utility of this method for investigating space use and aggression in wild fishes. Cuckoo wrasse (Labrus mixtus) were significantly more likely to display agonistic behaviour towards the laser than Goldsinny wrasse (Ctenolabrus rupestris). Goldsinny wrasse displayed a positive relationship between total length and chase‐distance, but not Cuckoo wrasse. The observed species differences may relate to behavioural factors affecting the motivation behind ‘laser‐chasing’, which is discussed. Chases by the cuckoo wrasse were significantly longer than those by Goldsinny wrasse, and these chase distances were used to estimate theoretical territory sizes for each species. To our knowledge, this is the first study to explore the spatial aspects of the reactions to an artificial stimulus by wild fishes. The potential to develop the method to directly investigate aspects of territoriality and aggression in wild fishes is discussed, including necessary further refinements and testing. Wild wrasses are increasingly exploited in Europe to provide cleaner fish for salmonid aquaculture, and we encourage the development of methods to inform spatial conservation measures for these ubiquitous and iconic species. 相似文献
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78.
Urmila Saha Asma Yasmeen Khan Sutanwi Bhuiya Suman Das Gaetano Fiorillo Paolo Lombardi 《Journal of biomolecular structure & dynamics》2019,37(6):1375-1389
Study on bioactive molecules, capable of stabilizing G-Quadruplex structures is considered to be a potential strategy for anticancer drug development. Berberrubine (BER) and two of its analogs bearing alkyl phenyl and biphenyl substitutions at 13-position were studied for targeting human telomeric G-quadruplex DNA sequence. The structures of berberrubine and analogs were optimized by density functional theory (DFT) calculations. Time-dependent DFT (B3LYP) calculations were used to establish and understand the nature of the electronic transitions observed in UV–vis spectra of the alkaloid. The interaction of berberrubine and its analogs with human telomeric G-quadruplex DNA sequence 5′-(GGGTTAGGGTTAGGGTTAGGG)-3′ was investigated by biophysical techniques and molecular docking study. Both the analogs were found to exhibit higher binding affinity than natural precursor berberrrubine. 13-phenylpropyl analog (BER1) showed highest affinity [(1.45 ± 0.03) × 105 M?1], while the affinity of the 13-diphenyl analog (BER2) was lower at (1.03 ± 0.05) × 105 M?1, and that of BER was (0.98 ± 0.03) × 105 M?1. Comparative fluorescence quenching studies gave evidence for a stronger stacking interaction of the analog compared to berberrubine. The thiazole orange displacement assay has clearly established that the analogs were more effective in displacing the end stacked dye in comparison to berberrubine. Molecular docking study showed that each alkaloid ligand binds primarily at the G rich regions of hTelo G4 DNA which makes them G specific binder towards hTelo G4 DNA. Isothermal titration calorimetry studies of quadruplex–berberrubine analog interaction revealed an exothermic binding that was favored by both enthalpy and entropy changes in BER in contrast to the analogs where the binding was majorly enthalpy dominated. A 1:1 binding stoichiometry was revealed in all the systems. This study establishes the potentiality of berberrubine analogs as a promising natural product based compounds as G-quadruplex-specific ligands. 相似文献
79.
The variogram is a standard tool in the analysis of spatial data, and its shape provides useful information on the form of spatial correlation that may be present. However, it is also useful to be able to assess the evidence for the presence of any spatial correlation. A method of doing this, based on an assessment of whether the true function underlying the variogram is constant, is proposed. Nonparametric smoothing of the squared differences of the observed variables, on a suitably transformed scale, is used to estimate variogram shape. A statistic based on a ratio of quadratic forms is proposed and the test is constructed by investigating the distributional properties of this statistic under the assumption of an independent Gaussian process. The power of the test is investigated. Reference bands are proposed as a graphical follow-up. An example is discussed. 相似文献
80.
An artificial host egg was developed as a first attempt to improve the techniques for in vitro rearing of Trichogramma galloi Zucchi and T. pretiosum Riley (Hymenoptera, Trichogrammatidae). Plastic membranes (polyethylene, polypropylene and polystyrene) of different thickness were tested for their usefulness in manufacturing artificial eggs, using a thermal system to produce semi-spherical cupules on the plastic surface. These artificial eggs were filled with larval hemolymph of Helicoverpa zea (Boddie) (Lepidoptera, Noctuidae), and the optimal size of the artificial egg and density of females/artificial egg for the highest host acceptance (percentage of artificial eggs with at least one parasitoid egg) as well as the ideal level of parasitism (eggs/artificial egg) were determined. High-density polyethylene 7–8 and 9–10 m thick resulted in the best acceptance and level of parasitization for both parasitoid species. Six females per artificial egg resulted in the best rate of parasitization for these parasitoids, although these data were not different when using 4 or 5 females of T. galloi. The size, shape and surface texture of the artificial eggs were found to provide enough cues to elicit parasitization behavior in Trichogramma females, since no chemical stimulus was provided. 相似文献