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51.
The uptake of morphine was significantly reduced in most regions of the brains of conscious, unrestrained rats within 10 minutes after treatment with an analog of ACTH/MSH (4–9), ORG-2766. The effect was most obvious in regions with significant densities of enkephalin receptors, namely basal ganglia, hippocampus and cortex. The results explain, in part, how some fragments and analogs of ACTH/MSH may antagonize behavioral actions of morphine, even though some of these peptides lack significant opiate receptor binding properties. We believe that this effect of ORG-2766 is related to an action on the permeability characteristics of the brain microvasculature. The underlying mechanism is unknown. 相似文献
52.
Purification and Characterization of an Autolysin from Clostridium acetobutylicum 总被引:9,自引:8,他引:1 下载免费PDF全文
Jocelyn R. Webster Sharon J. Reid David T. Jones David R. Woods 《Applied microbiology》1981,41(2):371-374
A proteinaceous substance with antibiotic-like activity, resembling that of a bacteriocin, was isolated from an industrial-scale acetone-butanol fermentation of Clostridium acetobutylicum. The substance, purified by acetone precipitation, diethylaminoethyl cellulose chromatography, and polyacrylamide gel electrophoresis, was characterized as a glycoprotein with a molecular weight of 28,000. The glycoprotein was partially inactivated by certain protease enzymes. It had no effect on deoxyribonucleic acid, ribonucleic acid, or protein synthesis, and it did not result in the loss of intracellular adenosine triphosphate. The glycoprotein lysed sodium dodecyl sulfate-treated cells and cell wall preparations, and therefore it is referred to as an autolysin. The autolysin gene appeared to be chromosomal since plasmid deoxyribonucleic acid was not detected in the C. acetobutylicum strain. 相似文献
53.
Selective-Differential Medium for Isolation and Differentiation of Pectinatus from Other Brewery Microorganisms 总被引:2,自引:2,他引:0 下载免费PDF全文
An agar medium, LL-agar (lactate-lead acetate) was designed to selectively differentiate members of the genus Pectinatus (S. Y. Lee, M. S. Mabee, and N. O. Jangaard, Int. J. Syst. Bacteriol. 28:582-594, 1978; S. Y. Lee, M. S. Mabee, N. O. Jangaard, and E. K. Horiuchi, J. Inst. Brew. 86:28-30, 1980) from other brewery microorganisms. Selectivity was achieved by the use of sodium lactate as the sole source of carbon and phenylethyl alcohol as an inhibitor for aerobic gram-negative bacteria and yeast. Differentiation was established by the introduction of lead acetate into the medium, which reacted with the H2S liberated by Pectinatus and resulted in a blackening of the Pectinatus colonies while the other brewery organisms, when present, remained white. In combination with the Lee tube (J. E. Ogg, S. Y. Lee, and B. J. Ogg, Can. J. Microbiol. 25:987-990, 1979) and this medium, isolation of Pectinatus organisms from beer samples was accomplished with convenience and simplicity. 相似文献
54.
Paul A. Price Sharon A. Baukol 《Biochemical and biophysical research communications》1981,99(3):928-935
1,25-dihydroxyvitamin D3 increases serum levels of bone Gla protein (BGP). The maximal increase occurs 12 h after injection and is given by 350 ng 1,25(OH)2D3 per 180 g body weight. In both 2 and 11 month-old male rats, the maximal increase is about 3 times the normal level, while in 2 month old female rats, the maximal increase is 2 times the normal level. These effects of 1,25(OH)2D3 in rats parallel the previously described effects of the vitamin on BGP secretion by rat osteosarcoma cells in culture.BGP is the first bone-specific protein whose synthesis in animals is dramatically increased by 1,25(OH)2D3. The possible functions of BGP in the biological actions of 1,25(OH)2D3 on bone are discussed. 相似文献
55.
Kazuaki Goriki Richard E. Tashian Sharon K. Stroup Ya-Shiou L. Yu Dag M. Henriksson 《Biochemical genetics》1979,17(5-6):449-460
A new inherited variant of carbonic anhydrase I (CA I), designated CA INagasaki 1 (CA INGS 1), was discovered during a survey of hemolysates from 5852 individuals from the cities of Hiroshima and Nagasaki in Japan. Analysis of the amino acid composition of a tryptic peptide from the CA INGS 1 variant indicated that a glutaminyl residue was substituted for an arginyl residue at position 76. Heat degradation studies showed that the CA INGS 1 variant was less stable than normal CA I. The CO2 hydrase and esterase activities of the normal and variant carbonic anhydrases I, as well as the relative amounts of the two enzymes in heterozygotes, were similar.This work was supported in part by Contract E(11-1)-1552 with the Energy Research and Development Administration, Washington, D.C. (to J. V. Neel), and by U.S. Public Health Service Grant GM-24681. 相似文献
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57.
Joseph W. Golden Xiankun Zeng Curtis R. Cline Jeffrey M. Smith Sharon P. Daye Brian D. Carey Candace D. Blancett Charles J. Shoemaker Jun Liu Collin J. Fitzpatrick Christopher P. Stefan Aura R. Garrison 《PLoS pathogens》2022,18(5)
Crimean-Congo hemorrhagic fever virus (CCHFV) is an important human pathogen. In cell culture, CCHFV is sensed by the cytoplasmic RNA sensor retinoic acid-inducible gene I (RIG-I) molecule and its adaptor molecule mitochondrial antiviral signaling (MAVS) protein. MAVS initiates both type I interferon (IFN-I) and proinflammatory responses. Here, we studied the role MAVS plays in CCHFV infection in mice in both the presence and absence of IFN-I activity. MAVS-deficient mice were not susceptible to CCHFV infection when IFN-I signaling was active and showed no signs of disease. When IFN-I signaling was blocked by antibody, MAVS-deficient mice lost significant weight, but were uniformly protected from lethal disease, whereas all control mice succumbed to infection. Cytokine activity in the infected MAVS-deficient mice was markedly blunted. Subsequent investigation revealed that CCHFV infected mice lacking TNF-α receptor signaling (TNFA-R-deficient), but not IL-6 or IL-1 activity, had more limited liver injury and were largely protected from lethal outcomes. Treatment of mice with an anti-TNF-α neutralizing antibody also conferred partial protection in a post-virus exposure setting. Additionally, we found that a disease causing, but non-lethal strain of CCHFV produced more blunted inflammatory cytokine responses compared to a lethal strain in mice. Our work reveals that MAVS activation and cytokine production both contribute to CCHFV pathogenesis, potentially identifying new therapeutic targets to treat this disease. 相似文献
58.
59.
Loiselle DR Thelin WR Parker CE Dicheva NN Kesner BA Mocanu V Wang F Milgram SL Warren MR Borchers CH 《Journal of proteome research》2005,4(3):992-997
In this work, a method for improved protein identification of low-abundance proteins using unstained gels, in combination with robotics and matrix-assisted laser desorption/ionization tandem mass spectrometry, has been developed and evaluated. Omitting the silver-staining process resulted in increased protein identification scores, an increase in the number of peptides observed in the MALDI mass spectrum, and improved quality of the tandem mass spectrometry data. 相似文献
60.
André-Denis G. Wright Andrew J. Williams Barbara Winder Claus T. Christophersen Sharon L. Rodgers Kellie D. Smith 《Applied microbiology》2004,70(3):1263-1270
The molecular diversity of rumen methanogens in sheep in Australia was investigated by using individual 16S rRNA gene libraries prepared from the rumen contents obtained from six merino sheep grazing pasture (326 clones), six sheep fed an oaten hay-based diet (275 clones), and five sheep fed a lucerne hay-based diet (132 clones). A total of 733 clones were examined, and the analysis revealed 65 phylotypes whose sequences (1,260 bp) were similar to those of cultivated methanogens belonging to the order Methanobacteriales. Pasture-grazed sheep had more methanogen diversity than sheep fed either the oaten hay or lucerne hay diet. Methanobrevibacter strains SM9, M6, and NT7 accounted for over 90% of the total number of clones identified. M6 was more prevalent in grazing sheep, and SM9, despite being found in 16 of the 17 sheep, was more prevalent in sheep fed the lucerne-based diet. Five new species were identified. Two of these species exhibited very little sequence similarity to any cultivated methanogens and were found eight times in two of the six sheep that were grazing pasture. These unique sequences appear to represent a novel group of rumen archaea that are atypical for the rumen environment. 相似文献