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1.
Arachidonic acid metabolites are mediators of various pathophysiologic events following endotoxin administration. However, their role in the endotoxin-induced increase in glucose metabolism has not been examined. Rats were administered either saline or BW755C (an inhibitor of both the cyclooxygenase and lipoxygenase pathways) 30 min prior to injection of E. coli endotoxin and whole body glucose kinetics assessed using a constant iv infusion of [6-3H] glucose. Treatment with BW755C prevented the endotoxin-induced hypotension and tachycardia. Endotoxin produced characteristic increases in the plasma glucose (23-70%) and lactate (2- to 9-fold) concentrations, as well as elevations in the rate of glucose appearance (34-63%) and metabolic clearance (40-92%). In contrast to the amelioration in hemodynamics, pretreatment with BW755C did not prevent these alterations in glucose metabolism normally seen after endotoxin. BW755C markedly reduced the endotoxin-induced increase in plasma catecholamine concentrations, but levels were still elevated 2- to 4-fold compared to control values. The results suggest that arachidonic acid metabolites mediate the early hypotensive response following endotoxin, but are not by themselves responsible for the elevated rates of glucose production and utilization. 相似文献
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cDNA cloning of the Octopus dofleini hemocyanin: sequence of the carboxyl-terminal domain 总被引:3,自引:0,他引:3
W H Lang 《Biochemistry》1988,27(19):7276-7282
A cDNA library was constructed in pUC 19, using poly(A+) RNA purified from Octopus dofleini branchial gland, which is the site of hemocyanin biosynthesis in cephalopods. The library was screened with an oligonucleotide probe derived from a portion of the partially known sequence of the C-terminal domain of Paroctopus dofleini dofleini. The clone with the longest insert--called pHC1--was sequenced and used as a probe for Northern blotting. It hybridized to a 9.5-kb RNA species, which was also visible as a band after ethidium bromide staining. The cDNA insert (approximately 1200 bp) of pHC1 contained an open reading frame of 1071 bp coding for 357 amino acids. In this insert, a region coding for 42 amino acids from the N-terminal end of the C-terminal domain is missing. These were obtained by sequencing a cloned primer extension product. By comparing our sequence with Helix pomatia beta c-hemocyanin unit D, we found 42.9% identical and 11.5% similar residues. One putative copper binding site (site B) was identified by homology to Helix hemocyanin and arthropodan hemocyanin. The location of a second possible site was identified. 相似文献
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Summary Utilizing coconut oilUstilago maydis ATCC 14826 synthesizes cellobiose lipids under N-limitation conditions and as resting cells, which gave the highest specific biosurfactant production (0.79 g/g substrate). C6-, C12-, C14-, and 15, 16-dihydroxy-C16-fatty acids are the main components of the lipophilic moiety of these glycolipids. 相似文献
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Joe Carver Domingos Ng Michelle Zhou Peggy Ko Dejin Zhan Mandy Yim David Shaw Brad Snedecor Michael W. Laird Steven Lang Amy Shen Zhilan Hu 《Biotechnology progress》2020,36(4):e2967
Historically, therapeutic protein production in Chinese hamster ovary (CHO) cells has been accomplished by random integration (RI) of expression plasmids into the host cell genome. More recently, the development of targeted integration (TI) host cells has allowed for recombination of plasmid DNA into a predetermined genomic locus, eliminating one contributor to clone-to-clone variability. In this study, a TI host capable of simultaneously integrating two plasmids at the same genomic site was used to assess the effect of antibody heavy chain and light chain gene dosage on antibody productivity. Our results showed that increasing antibody gene copy number can increase specific productivity, but with diminishing returns as more antibody genes are added to the same TI locus. Random integration of additional antibody DNA copies in to a targeted integration cell line showed a further increase in specific productivity, suggesting that targeting additional genomic sites for gene integration may be beneficial. Additionally, the position of antibody genes in the two plasmids was observed to have a strong effect on antibody expression level. These findings shed light on vector design to maximize production of conventional antibodies or tune expression for proper assembly of complex or bispecific antibodies in a TI system. 相似文献
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Dieke van Dinther Henrike Veninga Salvador Iborra Ellen G.F. Borg Leoni Hoogterp Katarzyna Olesek Marieke R. Beijer Sjoerd T.T. Schetters Hakan Kalay Juan J. Garcia-Vallejo Kees L. Franken Lamin B. Cham Karl S. Lang Yvette van Kooyk David Sancho Paul R. Crocker Joke M.M. den Haan 《Cell reports》2018,22(6):1484-1495
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In this publication, some special aspects of the topography in the nuchal region were examined as anatomical support for the dorsal approach to the posterior cranial fossa. The suboccipital muscles rectus capitis posterior minor and rectus capitis lateralis were measured concerning important characteristics as for instance their length and width. The proportions of some muscles arising from the atlas and the relations of the vertebral artery to defined points were evaluated. 相似文献