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91.
The effect of the antiarrhythmic drugs lidocaine, quinidine and procainamide on macrophage function was investigated in RAW 264.7 mouse monocytic macrophage cell. Cells stimulated by either zymosan or phorbol ester were found to generate both superoxide (O
2
–
) and H2O2. The production of O2 was detected as superoxide dismutase inhibitable ferricytochrome c reduction. H2O2 production was monitored in both chemical and flow cytometric fluorescent assays. Although all three drugs inhibited both O2 and H2O2 release in a dose dependent manner, only quinidine was found to have significant inhibitory effects. The amounts of quinidine required to cause a 50% inhibition in O2 production in zymosan and phorbol ester stimulated cells were found to be 250 M and 300 M, respectively and the amounts required to cause one-half optimum levels of H2O2 production in these cells were found to be 50 M and 100 M, respectively. The effect of these drugs on O2 producing NADPH oxidase was investigated and only procainamide was found to have a significant effect (p<0.001) in inhibiting the oxidase activity. Lidocaine and quinidine had no significant effect on the activation of the respiratory burst oxidase. A sensitive and convenient differential phagocytosis assay was devised on the basis of number of particles engulfed by individual phagocytes using flow cytometric techniques. It appears to be remarkably free of interference and was applied to investigate the role of antiarrhythmic drugs on the phagocytosis of fluorescent latex beads. All three antiarrhythmic drugs inhibited phagocytosis of latex beads in a dose dependent manner irrespective of the number of particles phagocitized by the cells. The results of these studies do not conclusively establish a mechanism of action of these drugs on the generation of O2 and H2O2 by stimulated macrophages; nevertheless, it is interesting that all three drugs inhibited the phagocytic activity. 相似文献
92.
93.
Filippo Aureli Marjolijn Das Désirée Verleur Jan A. R. A. M. van Hooff 《International journal of primatology》1994,15(3):471-485
We investigated the occurrence of postconflict social interactions in a group of Barbary macaques (Macaca sylvanus)that live in a large enclosure. We collected data during the mating and the nonmating seasons and analyzed them via two methods.
Separate analyses for the two seasons yielded very similar results. Reconciliation and redirection occurred. But we found
no evidence for consolation and postconflict kin-oriented affiliation. The consistency of these findings with those on other
species of Macacaindicates that reconciliation and redirection are typical postconflict social interactions of macaque victims. 相似文献
94.
The chromosome of Azotobacter vinelandii UW was digested separately with the rape cutter restriction endonucleases Swal (5-ATTTAAAT), PmeI (5GTTTAAAC) and Pacl (5-TTAATTAA) and the products were separated by pulsed-field gel electrophoresis. The size of the chromosome was determined to be approximately 4.5 megabase pairs (Mb) based on the sum of the sizes of the restriction fragments. This is almost the same as the size of the chromosome of Escherichia coli. The inability of the undigested DNA to enter the gel has led us to infer that the chromosome is circular. 相似文献
95.
Somatic embryogenesis was achieved from mid-rib and internodal calluses of Mussaenda erythrophylla L. cvs. Queen Sirikit and Rosea cultured on Murashige and Skoog basal medium containing 8.9 M BA+0.57 M IAA+10 mg l-1 ascorbic acid. Clumps of somatic embryos were separated and grown into complete plantlets when transferred to 1/2 MS medium+37 M adenine sulphate with 2% (w/v) sucrose. 相似文献
96.
Investigation on karyotype, 4C nuclear DNA amount and interphase nuclear volume (INV) of different HimalayanBupleurum species belonging toUmbelliferae revealed genetic differentiation. Numerical and structural alternation of chromosomes in interspecific level were manifested in their statistically significant altered species specific 4C nuclear DNA content. Somatic chromosome number ranged between 2n = 14 and 2n = 16.B. himalayense was reported for the first time having 2n = 16 chromosomes. Correlation coefficient among the various chromosomal and nuclear parameters showed no significant progressive or regressive interdependence except in between INV and nuclear DNA amount. Critical differences between 4C DNA content showed interspecific variation. 相似文献
97.
Hydrogen sulphide is a common toxic contaminant in natural gas and oil. In this study, the strictly autotrophic bacterium Thiobacillus ferrooxidans , which oxidizes reduced sulphur compounds, was used to desulphur petroleum oil and gas. The reaction was carried out in a closed vessel containing substrate mixed with a bacterial suspension. The significance of the hydrogen sulphide oxidizing activity of T. ferrooxidans is discussed. 相似文献
98.
99.
100.
Alen T. Mathew Anurag T. K. Baidya Bhanuranjan Das Bharti Devi Rajnish Kumar 《Proteins》2023,91(2):147-160
Various posttranslational modifications like hyperphosphorylation, O-GlcNAcylation, and acetylation have been attributed to induce the abnormal folding in tau protein. Recent in vitro studies revealed the possible involvement of N-glycosylation of tau protein in the abnormal folding and tau aggregation. Hence, in this study, we performed a microsecond long all atom molecular dynamics simulation to gain insights into the effects of N-glycosylation on Asn-359 residue which forms part of the microtubule binding region. Trajectory analysis of the stimulations coupled with essential dynamics and free energy landscape analysis suggested that tau, in its N-glycosylated form tends to exist in a largely folded conformation having high beta sheet propensity as compared to unmodified tau which exists in a large extended form with very less beta sheet propensity. Residue interaction network analysis of the lowest energy conformations further revealed that Phe378 and Lys353 are the functionally important residues in the peptide which helped in initiating the folding process and Phe378, Lys347, and Lys370 helped to maintain the stability of the protein in the folded state. 相似文献