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991.
Nakul Mandal Steffen Heegaard Jan Ulrik Prause Bent Honoré Henrik Vorum 《Biological procedures online》2010,12(1):56-88
The intention of this review is to provide an overview of current methodologies employed in the rapidly developing field of
ocular proteomics with emphasis on sample preparation, two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass
spectrometry (MS). Appropriate sample preparation for the diverse range of cells and tissues of the eye is essential to ensure
reliable results. Current methods of protein staining for 2D-PAGE, protein labelling for two-dimensional difference gel electrophoresis,
gel-based expression analysis and protein identification by MS are summarised. The uses of gel-free MS-based strategies (MuDPIT,
iTRAQ, ICAT and SILAC) are also discussed. Proteomic technologies promise to shed new light onto ocular disease processes
that could lead to the discovery of strong novel biomarkers and therapeutic targets useful in many ophthalmic conditions. 相似文献
992.
993.
Transgeni根癌农杆菌介导的小麦转基因植株再生(英文) 总被引:1,自引:0,他引:1
根癌农杆菌菌株Agl Ⅰ的Ti 质粒pUNN-2 带有Ubi1 启动子驱动的npt Ⅱ基因。7 种基因型小麦幼胚或胚性愈伤组织用于农杆菌介导的转化实验。经过不同浓度巴龙霉素的筛选,3 种基因型小麦产生抗性愈伤组织并再生植株。再生植株经PCR 和Southern 杂交鉴定为转基因植株,转化频率( 再生转基因植株的小麦愈伤组织数/ 用于转化实验的愈伤组织数) 为3.7% ~5 .9% 。小麦基因型及转化材料的起始生理状态是影响TDNA转移的重要因素。 相似文献
994.
995.
Nèjia Farhat Amine Elkhouni Walid Zorrig Abderrazak Smaoui Chedly Abdelly Mokded Rabhi 《Acta Physiologiae Plantarum》2016,38(6):145
Magnesium nutrition is often forgotten, while its absence adversely affects numerous functions in plants. Magnesium deficiency is a growing concern for crop production frequently observed in lateritic and leached acid soils. Competition with other cations (Ca2+, Na+, and K+) is also found to be an essential factor, inducing magnesium deficiency in plants. This nutrient is required for chlorophyll formation and plays a key role in photosynthetic activity. Moreover, it is involved in carbohydrate transport from source-to-sink organs. Hence, sugar accumulation in leaves that results from the impairment of their transport in phloem is considered as an early response to Mg deficiency. The most visible effect is often recorded in root growth, resulting in a significant reduction of root/shoot ratio. Carbohydrate accumulation in source leaves is attributed to the unique chemical proprieties of magnesium. As magnesium is a nutrient with high mobility in plants, it is preferentially transported to source leaves to prevent severe declines in photosynthetic activity. In addition, Mg is involved in the source-to-sink transport of carbohydrates. Hence, an inverse relationship between Mg shortage and sugar accumulation in leaves is often observed. We hereby review all these aspects with a special emphasis on the role of Mg in photosynthesis and the structural and functional effects of its deficiency on the photosynthetic apparatus. 相似文献
996.
Petri Tanska Petro Julkunen Rami K. Korhonen 《Biomechanics and modeling in mechanobiology》2018,17(3):689-699
Cartilage defects are a known risk factor for osteoarthritis. Estimation of structural changes in these defects could help us to identify high risk defects and thus to identify patients that are susceptible for the onset and progression of osteoarthritis. Here, we present an algorithm combined with computational modeling to simulate the disorganization of collagen fibril network in injured cartilage. Several potential triggers for collagen disorganization were tested in the algorithm following the assumption that disorganization is dependent on the mechanical stimulus of the tissue. We found that tensile tissue stimulus alone was unable to preserve collagen architecture in intact cartilage as collagen network reoriented throughout the cartilage thickness. However, when collagen reorientation was based on both tensile tissue stimulus and tensile collagen fibril strains or stresses, the collagen network architecture was preserved in intact cartilage. Using the same approach, substantial collagen reorientation was predicted locally near the cartilage defect and particularly at the cartilage–bone interface. The developed algorithm was able to predict similar structural findings reported in the literature that are associated with experimentally observed remodeling in articular cartilage. The proposed algorithm, if further validated, could help to predict structural changes in articular cartilage following post-traumatic injury potentially advancing to impaired cartilage function. 相似文献
997.
Chao Wei Wei Zhang Qiong Zhou Chao Zhao Ying Du Qi Yan Zhuyi Li Jianting Miao 《Neurochemical research》2016,41(8):1924-1938
Increasing evidence has shown that specificity protein 1 (Sp1) is abnormally increased in the brains of subjects with Alzheimer’s disease (AD) and transgenic AD models. However, whether the Sp1 activation plays a critical role in the AD pathogenesis and selective inhibition of Sp1 activation may have a disease-modifying effect on the AD-like phenotypes remain elusive. In this study, we reported that Sp1 mRNA and protein expression were markedly increased in the brain of APPswe/PS1dE9 transgenic mice, whereas chronic administration of mithramycin A (MTM), a selective Sp1 inhibitor, potently inhibited Sp1 activation in the APPswe/PS1dE9 mice down to the levels of wild-type mice. Specifically, we found that MTM treatment resulted in a significant improvement of learning and memory deficits, a dramatic reduction in cerebral Aβ levels and plaque burden, a profound reduction in tau hyperphosphorylation, and a marked increase in synaptic marker in the APPswe/PS1dE9 mice. In addition, MTM treatment was powerfully effective in inhibiting amyloid precursor protein (APP) processing via suppressing APP, beta-site APP cleaving enzyme 1 (BACE1), and presenilin-1 (PS1) mRNA and protein expression to preclude Aβ production in the APPswe/PS1dE9 mice. Furthermore, MTM treatment strongly inhibited phosphorylated CDK5 and GSK3β signal pathways to reduce tau hyperphosphorylation in the APPswe/PS1dE9 mice. Collectively, our findings provide evidence that Sp1 activation may contribute to the AD pathogenesis and may serve as a novel therapeutic target in the treatment of AD. The present study highlights that selective Sp1 inhibitors may be considered as disease-modifying therapeutic agents for AD. 相似文献
998.
我国盐碱土面积约9913万hm2,其中pH值高于9、盐含量大于0.6%的重度盐碱地每年以1.4%的速率增长。利用固氮微生物改善植物根际环境,提高作物产量,是盐碱地改良的重要方法。[目的] 从来自海南省三沙市热带珊瑚岛礁的土壤中,分离鉴定自生固氮菌,为极端盐碱地改良提供候选菌株。[方法] 通过形态学观察、生理生化特征分析和16S rRNA序列测定等方法进行菌种鉴定,分析其固氮、耐盐碱和促生长特性,盆栽试验验证其对玉米主要农艺性状的影响。[结果] 获得1株极端耐盐碱的固氮细菌DJ-1,其菌落呈圆形,菌体杆状,大小(0.5-1.3)μm×(0.3-0.5)μm,革兰氏染色阴性,与根癌土壤杆菌(Agrobacterium tumefaciens)的16S rRNA序列高度同源,确定其为根癌土壤杆菌。DJ-1在pH 9、NaCl含量为1%-4%的培养基上可正常生长,能耐受pH 12、NaCl含量8%的环境。从中克隆到固氮酶基因nifH。盆栽试验结果表明,DJ-1可显著促进玉米生长。[结论] 菌株DJ-1能耐受极端盐碱条件,且具有较强的固氮和促生长能力,有可能作为贫瘠盐碱耕地改良功能菌剂的候选菌株。 相似文献
999.
Johannes W. S. A. Osterloh Arjan C. Videler Gina M. P. Rossi Sebastiaan P. J. van Alphen 《Tijdschrift voor gerontologie en geriatrie》2018,49(5):210-212
Behavioural counselling by nurses can enhance quality of life in elderly with a personality disorder. Although nurses have a crucial role in day-to-day treatment, there is a lack of evidence-based approaches. Based on the cognitive therapy, the treatment protocol Cognitive Model for Behavioural Interventions (CoMBI) provides an alternative nursing approach for personality disorders. 相似文献
1000.
Ammar Almaaytah Adan Alnaamneh Ahmad Abualhaijaa Nizar Alshari’ Qosay Al-Balas 《International journal of peptide research and therapeutics》2016,22(4):497-504
The extensive use of antibiotics for the treatment of human infections during the last few decades has led to a dramatic increase in the emergence of multidrug-resistant bacteria (MDRB) among various bacterial strains. Global research is currently focused on finding novel alternative agents with different mechanisms of action rather than the use of conventional antibiotics to counteract the threat of bacterial and biofilm infections. Antimicrobial peptides represent promising alternative agents for conventional antibiotics as these molecules display a broad spectrum of activity against several microorganisms. Recently, we have designed a novel hybrid antimicrobial peptide named MelitAP-27. This peptide has been found to display potent broad spectrum and selective in vitro antimicrobial activities against a wide range of Gram-positive and Gram-negative bacteria. In the present study, the in vitro antimicrobial and antibiofilm activities of the peptide alone and in combination with five different types of antibiotics were assessed against wild-type and resistant Gram-positive and Gram-negative bacterial strains. Our results showed that most of the combination groups displayed a synergistic mode of action against planktonic and biofilm forming bacteria which resulted in decreasing the effective MIC values for MelitAP-27 to the nanomolar concentrations. These effective concentrations were associated with negligible toxicities on mammalian cells. The results of our study indicate that combinations of MelitAP-27 with conventional antibiotics may be pursued as a potential novel treatment strategy against MDRB and biofilm forming bacteria. 相似文献