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301.
302.
Daniel J. Metcalf Rebecca Edwards Neelam Kumarswami Alex E. Knight 《Journal of visualized experiments : JoVE》2013,(79)
STORM is a recently developed super-resolution microscopy technique with up to 10 times better resolution than standard fluorescence microscopy techniques. However, as the image is acquired in a very different way than normal, by building up an image molecule-by-molecule, there are some significant challenges for users in trying to optimize their image acquisition. In order to aid this process and gain more insight into how STORM works we present the preparation of 3 test samples and the methodology of acquiring and processing STORM super-resolution images with typical resolutions of between 30-50 nm. By combining the test samples with the use of the freely available rainSTORM processing software it is possible to obtain a great deal of information about image quality and resolution. Using these metrics it is then possible to optimize the imaging procedure from the optics, to sample preparation, dye choice, buffer conditions, and image acquisition settings. We also show examples of some common problems that result in poor image quality, such as lateral drift, where the sample moves during image acquisition and density related problems resulting in the ''mislocalization'' phenomenon. 相似文献
303.
Nagarajan Muthukaman Sanjay Deshmukh Shital Tondlekar Macchindra Tambe Dnyandeo Pisal Neelam Sarode Siddharth Mhatre Samitabh Chakraborti Daisy Shah Vikram M. Bhosale Abhay Kulkarni Mahamad Yunnus A. Mahat Satyawan B. Jadhav Girish S. Gudi Neelima Khairatkar-Joshi Laxmikant A. Gharat 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3766-3773
Endogenous nitrosothiols (SNOs) including S-nitrosoglutathione (GSNO) serve as reservoir for bioavailable nitric oxide (NO) and mediate NO-based signaling, inflammatory status and smooth muscle function in the lung. GSNOR inhibition increases pulmonary GSNO and induces bronchodilation while reducing inflammation in lung diseases. In this letter, design, synthesis and structure–activity relationships (SAR) of novel imidazole-biaryl-tetrazole based GSNOR inhibitors are described. Many potent inhibitors (30, 39, 41, 42, 44, 45 and 58) were identified with low nanomolar activity (IC50s: <15?nM) along with adequate metabolic stability. Lead compounds 30 and 58 exhibited good exposure and oral bioavailability in mouse pharmacokinetic (PK) study. Compound 30 was selected for further profiling and revealed comparable mouse and rat GSNOR potency, high selectivity against alcohol dehydrogenase (ADH) and carbonyl reductase (CBR1) family of enzymes, low efflux ratio and permeability in PAMPA, a high permeability in CALU-3 assay, significantly low hERG activity and minimal off-target activity. Further, an in vivo efficacy of compound 30 is disclosed in cigarette smoke (CS) induced mouse model for COPD. 相似文献
304.
Valiya Nadakkakath Agisha Aundy Kumar Neelam Sheoran Rajamma Suseelabhai 《Biocontrol Science and Technology》2019,29(11):1069-1089
ABSTRACTBlack pepper endophytic Pseudomonas putida BP25 produced diverse antimicrobial volatile organic compounds having potential for plant disease management. Chemically synthesised volatiles such as 2, 5-dimethyl pyrazine; 2-methyl pyrazine; dimethyl trisulphide; 2-ethyl 5-methyl pyrazine; and 2-ethyl 3, 6-dimethyl pyrazine showed inhibitory activity against oomycete pathogens, Phytophthora capsici & Pythium myriotylum; fungal pathogens, Rhizoctonia solani, Colletotrichum gloeosporioides, Athelia rolfsii, Gibberella moniliformis & Magnaporthe oryzae; bacterial pathogen, Ralstonia pseudosolanacearum and plant parasitic nematode, Radopholus similis. Among them, dimethyl trisulphide completely inhibited oomycete and fungal pathogens as well as R. similis at a concentration of 2.65?µg?cm?3 under in vitro conditions. Pyrazines suppressed Phytophthora lesions on shoot cuttings of black pepper upon in planta volatile treatment. Dimethyl trisulphide was the only compound that exhibited soil fumigant activity against P. capsici, R. solani and A. rolfsii (6.25?µg?cm?3), C. gloeosporioides and G. moniliformis (12.5?µg?cm?3), and R. similis (50?µg?cm?3). Altogether, endophytic Pseudomonas putida BP25 and its volatile organic compounds offer an alternative strategy for eco-friendly disease management in agriculture. 相似文献
305.
Mannan transglycosylases are cell wall enzymes able to transfer part of the mannan polysaccharide backbone to mannan-derived oligosaccharides (Schröder et al. in Planta 219:590–600, 2004). Mannan transglycosylase activity was purified to near homogeneity from ripe tomato fruit. N-terminal sequencing showed that the dominant band seen on SDS-PAGE was identical to LeMAN4a, a hydrolytic endo-β-mannanase found in ripe tomato fruit (Bewley et al. in J Exp Bot 51:529–538, 2000). Recombinant LeMAN4a protein expressed in Escherichia coli exhibited both mannan hydrolase and mannan transglycosylase activity. Western analysis of ripe tomato fruit tissue using an antibody raised against tomato seed endo-β-mannanase revealed four isoforms present after 2D-gel electrophoresis in the pH range 6–11. On separation by preparative liquid isoelectric focussing, these native isoforms exhibited different preferences for transglycosylation and hydrolysis. These results demonstrate that endo-β-mannanase has two activities: it can either hydrolyse mannan polysaccharides, or in the presence of mannan-derived oligosaccharides, carry out a transglycosylation reaction. We therefore propose that endo-β-mannanase should be renamed mannan transglycosylase/hydrolase, in accordance with the nomenclature established for xyloglucan endotransglucosylase/hydrolase. The role of endo-acting mannanases in modifying the structure of plant cell walls during cell expansion, seed germination and fruit ripening may need to be reinterpreted in light of their potential action as transglycosylating or hydrolysing enzymes. 相似文献
306.
Purification of an isoform of patatin with antimicrobial activity against Phytophthora infestans. 总被引:1,自引:0,他引:1
Neelam Sharma Hope A Gruszewski Sang-Wook Park David G Holm Jorge M Vivanco 《Plant Physiology and Biochemistry》2004,42(7-8):647-655
Phytophthora infestans (Mont.) de Bary is infamous as the causal agent of the late blight epidemic contributing to the Irish potato famine of the mid 19th century and remains agriculture's most destructive disease as new mutations and migrations confound control measures. In efforts to develop resistant varieties, a somatic hybrid (the Wisconsin J series) between potato (Solanum tuberosum) and a wild relative (Solanum bulbocastanum) has been found to convey durable resistance against the pathogen. We screened the total protein (100 microg ml(-1)) of somatic hybrid varieties J138, J138A12, J101K12, J103K12, and J101K9 for in vitro spore germination inhibition of P. infestans. Since J138 exhibited maximum inhibition at 150 microg ml(-1) in comparison to other varieties, we purified a 40 kD protein from J138 tubers by assaying its ability to inhibit spore germination in P. infestans spores. The highly purified protein was able to inhibit P. infestans spore germination by 70% at the 2.5 microg ml(-1) concentration. The N-terminal sequence of this protein was found to have exact amino acid homology to patatin, the major storage protein of potato tubers. The inhibitory protein has the same molecular weight as patatin and cross-reacts with patatin antibodies. The infection of J138 plants with spores of P. infestans under greenhouse conditions showed that patatin is expressed in stem tissue 72 h after the plant is inoculated with field isolates of P. infestans (US8). In this communication, we report the purification, characterization and antifungal activity against spores of P. infestans of patatin-J from potato tubers. 相似文献
307.
Molecular Biology Reports - Genus Ocimum is known to have species possessing important therapeutic essential oil. The major phytoconstituents of essential oil in Ocimum species are... 相似文献
308.
Anusha Dhaval Neelam Yadav Shalini Purwar 《International journal of peptide research and therapeutics》2016,22(3):377-398
Recently the rise in noncommunicable diseases and side effects of drugs has promoted the research in food components with biologically active molecules. These bioactive components are vital in reducing and regulating the onset of such chronic degenerative diseases. Many food derived peptides are biologically active fragments encrypted within the primary protein sequence in nascent (inactive) form, hence also called ‘cryptides’. These bioactive peptides range in size from 2 to 50 amino acids. They function beyond their basic nutritional benefits. Upon oral administration, these peptides play various roles such as opiate like, antioxidative, immunomodulatory, antihypertensive, hypocholesterolemic, mineral binding, antiobesity and antimicrobial. Both animal and plant proteins are rich sources of bioactive peptides having specific physiological and biochemical functions. Digestion of proteins in vivo or in vitro produces free amino acids and peptides which enter circulatory system and exert systemic effect. Bioactive peptides can be produced in vivo through gastrointestinal digestion whereas in vitro through chemical processing of food proteins with acid, alkali, heat and enzymatic hydrolysis either by digestion or fermentation. Protein hydrolysates being rich source of bioactive peptides can serve as an alternative to intact protein and elemental formula in the development of functional foods. 相似文献
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310.
Stephanie Puukila Sean Bryan Anna Laakso Jessica Abdel-Malak Carli Gurney Adrian Agostino Adriane Belló-Klein Kailash Prasad Neelam Khaper 《PloS one》2015,10(3)
Cardiac iron overload is directly associated with cardiac dysfunction and can ultimately lead to heart failure. This study examined the effect of secoisolariciresinol diglucoside (SDG), a component of flaxseed, on iron overload induced cardiac damage by evaluating oxidative stress, inflammation and apoptosis in H9c2 cardiomyocytes. Cells were incubated with 50 μ5M iron for 24 hours and/or a 24 hour pre-treatment of 500 μ M SDG. Cardiac iron overload resulted in increased oxidative stress and gene expression of the inflammatory mediators tumor necrosis factor-α, interleukin-10 and interferon γ, as well as matrix metalloproteinases-2 and -9. Increased apoptosis was evident by increased active caspase 3/7 activity and increased protein expression of Forkhead box O3a, caspase 3 and Bax. Cardiac iron overload also resulted in increased protein expression of p70S6 Kinase 1 and decreased expression of AMP-activated protein kinase. Pre-treatment with SDG abrogated the iron-induced increases in oxidative stress, inflammation and apoptosis, as well as the increased p70S6 Kinase 1 and decreased AMP-activated protein kinase expression. The decrease in superoxide dismutase activity by iron treatment was prevented by pre-treatment with SDG in the presence of iron. Based on these findings we conclude that SDG was cytoprotective in an in vitro model of iron overload induced redox-inflammatory damage, suggesting a novel potential role for SDG in cardiac iron overload. 相似文献