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91.
92.
Effects of different preparations of propofol, diazepam, and etomidate on human neutrophils in vitro 总被引:4,自引:0,他引:4
Heine J Jaeger K Weingaertner N Scheinichen D Marx G Piepenbrock S 《Acta anaesthesiologica Scandinavica》2001,45(2):213-220
BACKGROUND: Intravenous anaesthetics and sedatives can influence polymorphonuclear cell (PMN) functions. Some of the drugs for sedation and anaesthesia have been alternatively dissolved in lipid solutions containing medium (MCT) and/or long chain (LCT) triglycerides. The in vitro effects of two different diazepam (benzyl-alcohol, LCT/MCT), etomidate (propylene-glycol, LCT/MCT), and propofol (LCT, LCT/MCT) preparations on respiratory burst (RB) and phagocytosis of human PMNs were studied. METHODS: Diazepam (2, 20 microg ml(-1)), etomidate (0.5, 5 microg ml(-1)), and propofol (6, 60 microg ml(-1)) were investigated in clinical and 10-fold concentrations with flow cytometric assays. The RB was measured with the fluorescent dye rhodamine after induction with Escherichia coli or formyl-methionyl-leucylphenylalanine (FMLP) following priming with tumour necrosis factor alpha (TNF-alpha). Phagocytosis of PMNs was carried out in whole blood after incubation with fluorescein-labelled E. coli. RESULTS: LCT-propofol at 60 microg ml(-1) reduced the percentage of PMNs with RB activity after induction with E. coli (52.8+/-20.4) and TNF-alpha/FMLP (10.8+/-5.1)) as well as the percentage of phagocytosing PMNs (48.9+/-19.5) in contrast to LCT/MCT-propofol, which augmented all parameters (85.4+/-10.1, 50.3+/-12.7, 66.5+/-12.5). Also the higher concentrations of LCT/MCT-diluted etomidate and diazepam increased the percentage of RB positive PMNs compared to the alternative compositions. The percentage of phagocytosing PMNs was less reduced with 20 microg ml(-1) LCT/MCT-diazepam (85.2+/-6.9) than with the same concentration of benzyl-alcohol diluted diazepam (68.8+/-12.2) compared to the control. CONCLUSION: The in vitro effects of diazepam, etomidate, and propofol are dependent on the solvent applied. The tested LCT/MCT preparations reduce the inhibitory effects on the bacterial killing capacity of PMNs found after incubation with propyleneglycol, benzyl-alcohol, or LCT preparations, respectively. 相似文献
93.
茜草双酯对小鼠免疫功能的抑制作用(英文) 总被引:5,自引:0,他引:5
目的:研究茜草双酯对正常小鼠免疫功能的影响.方法:采用免疫药理学常用方法即血清溶菌酶含量的测定,迟发型超敏反应的测定,血清溶血素的测定,[~3H]TdR参入的小鼠全血白细胞吞噬能力的测定,鼠脾空斑形成细胞溶血能力的测定,T和B淋巴细胞转化能力的测定.结果:茜草双酯125,500,2000mg·kg~(-1)·d~(-1)降低血清溶菌酶含量和全血白细胞吞噬功能;使PFC溶血能力和HC_(50)产生减少;抑制DTH反应;体内给药体外测定,抑制[~3H]TdR参入的PHA与LPS诱导的淋巴细胞转化.以上作用呈一定的剂量依赖性.结论:茜草双酯对正常小鼠特异和非特异性免疫功能均有不同程度的抑制作用. 相似文献
94.
Venous blood from healthy premature infants, premature infants with known bacterial infections, normal term infants and adults, was incubated in vitro with Pseudomonas aeruginosa. At 30 min intervals, blood samples were tested for the nitroblue-tetrazolium (NBT) reducing activity of neutrophils. The results of the histochemical NBT test were compared with those of the blood controls from which bacteria were omitted. The stimulation of neutrophils with Ps. aeruginosa induces a considerable increase of NBT reduction in all 4 groups of subjects examined. The maximum rate of NBT reduction was observed after 1 hour of incubation with the test organism, and reached its lowest degree after 3 hours. By contrast the NBT reduction by un-stimulated neutrophils of the same subjects remain unchanged during a 3 hour period of incubation. 相似文献
95.
96.
Several characteristics of the binding of insulin and glucagon to human circulating mononuclear leukocytes have been studied. Functional analysis (latex bead ingestion) revealed that cell mixtures, as prepared according to Boyum and used generally in studies of insulin resistance in humans, consist of 20-29% phagocytic monocytes, with the remainder being lymphocytes. Partial separation of monocytes from lymphocytes on columns of Sephadex G-10, followed by correlation of insulin binding with cell type, confirms that the monocyte is the binding species. Insulin influenced neither glucose uptake nor the further conversion of glucose to lipids and CO2 by the leukocytes. The transport of alpha-aminoisobutyrate, a nonmetabolizable amino acid, into these cells was also unaffected by insulin. Monocyte/lymphocyte mixtures specifically bound glucagon and prostaglandin E1. At physiological concentrations of these hormones, steady states were reached in 15 min and 45 min, respectively. In contrast to the 8-10-fold increases in cellular cyclic AMP produced by prostaglandins, the effect of glucagon was very small but apparently real. Under appropriate preincubation conditions, sodium azide and iodoacetamide inhibited phagocytosis and insulin binding in parallel. The binding of glucagon was unaffected by these agents. Although both antimycin A and actinomycin D inhibited phagocytosis of the monocytes, only the former inhibited insulin binding; there was only a slight effect on glucagon binding. We would conclude that the binding of insulin to human circulating monocytes, although reflective of insulin resistance in diabetes mellitus and obesity, may not be to traditional receptors. In contrast, the binding of glucagon to lymphocyte/monocyte mixtures may be to function-linked receptors. 相似文献
97.
A I Goldman P J O'Brien E Masterson P Israel P Teirstein G Chader 《Experimental eye research》1979,28(4):455-467
A quantitative assay for phagocytosis has been described using a heterologous system of chick pigment epithelial culture and radiolabeled bovine rod outer segment suspensions. Electron microscopy was used to verify results obtained in radiolabeled uptake studies. Freezing and mild shearing of the outer segment suspensions do not significantly inhibit phagocytosis. Outer segments radiolabeled with [3H]choline and [14C]mannose showed similar kinetics of phagocytosis. Maximum uptake was between 1 and 2 hr of incubation and approached 1% of the total applied radioactivity for mannose and 2% for choline. 相似文献
98.
Henryk M. Winiewski Bernardino Ghetti Dikran S. Horoupian 《Journal of neurocytology》1972,1(3):297-310
Summary The fate of synaptic membranes of degenerating optic nerve terminals has been studied in the lateral geniculate nucleus of Rhesus monkey after eye enucleation. It was shown that pre-synaptic and post-synaptic membranes remain in close apposition to each other during all stages of degeneration and phagocytosis of affected terminals. As a result of this, fragments of presynaptic terminals were engulfed within glial processes, together with synaptic thickenings and parts of post-synaptic dendrites. On occasion small pieces of the degenerating terminals together with the synaptic membranes were engulfed by the post-synaptic dendrite. It is proposed that this pattern of removal of degenerating optic terminals results in injury to the post-synaptic cells, and triggers the transneuronal degeneration. 相似文献
99.
Abstract. A new variant of G-6-PD with chronic nonspherocytic haemolytic anaemia and very low activity, named G-6-PD Hamburg, was partially purified and biochemically characterized. It was found to have very high lability, an unusually high Km for G-6-P (2000 μM), increased utilization rates for 2-desoxy G-6-P (133%) and galactose-6-phosphate (87%) and an abnormal pH-activity curve. The electrophoretic mobility seemed to be normal. The leukocytes also revealed diminished G-6-PD activity. No impairment of bactericidal activity of neutrophilic granulocytes, as shown by a normal nitroblue tetrazolium reduction, could be demonstrated. 相似文献
100.
Antibody- and complement-independent phagocytotic and cytolytic activities of human macrophages toward porcine cells 总被引:2,自引:0,他引:2
BACKGROUND: It has been speculated that host macrophages contribute to rapid clearance of transplanted xenogeneic cells. To address such a possibility, phagocytotic and cytolytic activities of human macrophages toward xenogeneic porcine cells were evaluated in vitro in the absence of antibodies and complement factors. METHODS: Human peripheral monocyte-derived macrophages (P-macrophages) and reticulo-endothelial macrophages (RE-macrophages) were obtained from volunteers' peripheral blood and from the perfusion effluents of liver allografts for transplantation, respectively. 5-(and 6-) carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled human autologous red blood cells (auto-RBCs), ABO-incompatible RBCs (incom-RBCs) and xenogeneic porcine RBCs (xeno-RBCs) were incubated with the human macrophages; subsequently, the macrophages that had phagocytosed the RBCs could be identified as CFSE positive cells by FCM analyses and confocal microscopy. Cytolytic activity was quantified by calculating levels of lactate dehydrogenase in each culture supernatant. RESULTS: Human RE-macrophages spontaneously phagocytosed and had a remarkable cytolytic activity toward xeno-RBCs, but not toward auto-RBCs or incom-RBCs. Elimination of alpha-galactosyl xenoantigen (alpha-Gal) epitopes on xeno-RBCs did not prevent phagocytotic or cytolytic activity of RE-macrophages. CONCLUSIONS: These findings indicate phagocytotic and cytolitic activities of human macrophages toward porcine cells are initiated by a factor other than alpha-Gal in a mechanism independent of antibody/complement opsonization. 相似文献