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911.
Inflammation is a fundamental aspect of many human diseases. In this video report, we demonstrate non-invasive bioluminescence imaging techniques that distinguish acute and chronic inflammation in mouse models. With tissue damage or pathogen invasion, neutrophils are the first line of defense, playing a major role in mediating the acute inflammatory response. As the inflammatory reaction progresses, circulating monocytes gradually migrate into the site of injury and differentiate into mature macrophages, which mediate chronic inflammation and promote tissue repair by removing tissue debris and producing anti-inflammatory cytokines. Intraperitoneal injection of luminol (5-amino-2,3-dihydro-1,4-phthalazinedione, sodium salt) enables detection of acute inflammation largely mediated by tissue-infiltrating neutrophils. Luminol specifically reacts with the superoxide generated within the phagosomes of neutrophils since bioluminescence results from a myeloperoxidase (MPO) mediated reaction. Lucigenin (bis-N-methylacridinium nitrate) also reacts with superoxide in order to generate bioluminescence. However, lucigenin bioluminescence is independent of MPO and it solely relies on phagocyte NADPH oxidase (Phox) in macrophages during chronic inflammation. Together, luminol and lucigenin allow non-invasive visualization and longitudinal assessment of different phagocyte populations across both acute and chronic inflammatory phases. Given the important role of inflammation in a variety of human diseases, we believe this non-invasive imaging method can help investigate the differential roles of neutrophils and macrophages in a variety of pathological conditions. 相似文献
912.
Isolation of chloroplasts free from nuclear DNA contamination 总被引:2,自引:0,他引:2
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914.
D A Tinker M Kung J T Brosnan G R Herzberg 《The International journal of biochemistry》1983,15(10):1225-1230
Computer analysis of the subcellular distribution of phosphoenolpyruvate carboxykinase in adult female (Gallus domesticus) chicken liver indicates that the activity is distributed between the mitochondria and nucleus in the ratio 70: 30%. There was no activity found in the cytosol. Newly hatched chicks and 8-week-old juveniles were found to have a significant soluble hepatic PEPCK activity. The particulate activity of PEPCK in the livers of juveniles raised in continuous light (24L:0D) decreased over the course of a 7-day fast while no such decrease was seen in juveniles raised in a 12-hr daylength photoperiod (12L:12D). 相似文献
915.
DNA sequence encoding the amino-terminal region of the human c-src protein: implications of sequence divergence among src-type kinase oncogenes. 总被引:21,自引:9,他引:12 下载免费PDF全文
A Tanaka C P Gibbs R R Arthur S K Anderson H J Kung D J Fujita 《Molecular and cellular biology》1987,7(5):1978-1983
We sequenced the 5'-coding region of the human c-src gene, exons 2 through 5, corresponding to one-third of the human c-src protein consisting of 536 amino acids. Sequence analysis of the src type of protein kinases revealed that the amino-terminal region encoded by exon 2 contains sequences specific for the src proteins and raised the possibility that this region is involved in the recognition of a src-specific substrate(s) or receptor(s). 相似文献
916.
Quantification of three‐dimensional (3D) refractive index (RI) with sub‐cellular resolution is achieved by digital holographic microtomography (DHμT) using quantitative phase images measured at multiple illumination angles. The DHμT system achieves sensitive and fast phase measurements based on iterative phase extraction algorithm and asynchronous phase shifting interferometry without any phase monitoring or active control mechanism. A reconstruction algorithm, optical diffraction tomography with projection on convex sets and total variation minimization, is implemented to substantially reduce the number of angular scattered fields needed for reconstruction without sacrificing the accuracy and quality of the reconstructed 3D RI distribution. Tomogram of a living CA9‐22 cell is presented to demonstrate the performance of the method. Further, a statistical analysis of the average RI of the nucleoli, the nucleus excluding the nucleoli and the cytoplasm of twenty CA9‐22 cells is performed. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
917.
Adrenocorticotropin (ACTH)-treated adrenalectomized rats subjected to crush denervation recover sensation and functional movement sooner than saline-treated rats. Axonal regeneration is accelerated, the number of large endplates and the frequency of preterminal branching are increased. ACTH has no effect on either intact or denervated muscles. The ameliorative action of ACTH during regeneration is apparently neurogenic and independent of corticoids. 相似文献
918.