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21.
Ketamine inhibits LPS-induced calcium elevation and NF-kappa B activation in monocytes 总被引:10,自引:0,他引:10
Objective:To investigate whether ketamine could inhibit lipopolysaccharide (LPS)-induced intracellular calcium elevation and NF-kappa B activation in monocytes.
Materials and methods:Isolated rat monocytes were challenged with 10 g/ml LPS with or without the presence of various concentrations of ketamine (10, 100, 1000 M). Intracellular calcium was monitored by laser confocal microscopy. NF-kappa B activity of the nuclear extracts of monocytes was analyzed by electrophoretic mobility shift assay (EMSA).
Results:LPS provoked a significant calcium elevation and enhanced NF-kappa B activity in monocytes. Ketamine above concentration of 100 M inhibited endotoxin-induced intracellular calcium elevation and NF-kappa B activity. Ketamine itself had no effect on either of them.
Conclusions:These findings suggest that ketamine could suppress NF-kappa B in monocytes exposed to endotoxin, and this anti-inflammatory effect might act through attenuating intracellular calcium elevation.Received 31 October 2003; returned for revision 18 December 2003; accepted by I. Ahnfelt-Rønne 26 Januaryy 2004 相似文献
22.
人外周血树突状细胞培养和地塞米松对其分化的影响作用 总被引:1,自引:0,他引:1
目的分离培养和鉴定人外周血树突状细胞(DC),以及探讨地塞米松对其分化的影响作用。方法密度梯度离心法分离人外周血单个核细胞,贴壁后加入GM-CSF、IL-4和LPS培养,部分组另加入地塞米松,观察细胞形态学、流式标志和DC与T淋巴细胞共培养后的增殖变化。结果外周血单核细胞诱导培养后具有DC形态学特征,CD83表达上调,CD14表达下调,DC与T淋巴细胞共培养后呈增殖反应。培养液中加入地塞米松后CD83表达下调,CD14表达上调,DC与T淋巴细胞共培养后增殖反应减弱。结论外周血单核细胞经联合细胞因子可诱导为DC;地塞米松可使DC在功能上处于不成熟状态。 相似文献
23.
Recent evidence shows that circulating leukocytes respond not only to humoral inflammatory mediators but also to fluid stresses. Application of fluid shear stress (of the order of 1–10 cm2 to fresh migrating leukocytes leads to initial retraction of pseudopods, an important step to facilitate normal passage of leukocytes through the microcirculation and to prevent spreading on the endothelium. The ability to respond to fluid shear stress, however, may be regulated under different physiological conditions. In the current study, we examine the role of integrins in the fluid shear response as measured by pseudopod retraction with the use of antibodies against human neutrophil 1 and 2 integrins. Neutrophils adhering via 2 integrins exhibit normal ability to project pseudopods and to migrate. Such cells show normal response to fluid shear with rapid pseudopod retraction. In contrast, attachment via 1 integrins leads to firmly adhesive leukocytes, spreading and almost no cell migration. Such leukocytes exhibit a significantly attenuated ability for pseudopod retraction under fluid shear. These results suggest that integrins may serve as a regulating mechanism for fluid shear response in human leukocytes. Attachment via 1 integrins may lead to an abolishment of the fluid shear response. © 2002 Biomedical Engineering Society.
PAC2002: 8716-b, 8719Tt 相似文献
24.
Jonathan T. Sims Venkatesh Krishnan Ching-Yun Chang Sarah M. Engle Giacomo Casalini George H. Rodgers Nicoletta Bivi Brian J. Nickoloff Robert J. Konrad Stephanie de Bono Richard E. Higgs Robert J. Benschop Silvia Ottaviani Anabela Cardoso Ajay Nirula Mario Corbellino Justin Stebbing 《The Journal of allergy and clinical immunology》2021,147(1):107-111
25.
Alessandro Poggi Anna Rubartelli Lorenzo Moretta Maria Raffaella Zocchi 《European journal of immunology》1997,27(11):2965-2970
In this study, we analyzed the expression and function of the lymphocyte surface lectin NKRP1A on peripheral blood monocytes (Mo) or Mo and dendritic cells (DC) derived from thymic and bone marrow precursors. De novo expression of NKRP1A and CD14 molecules was detected upon culture of CD2? CD3? CD14? CD16? CD1a? NKRP1A? immature thymic precursors for 7 days in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF). Under these culture conditions, by day 21, a fraction of cells had lost CD14 and acquired both CD80 (B7.1) and CD86 (B7.2) molecules. These cells displayed a DC-like morphology and were surface NKRP1A positive. CD34+ NKRP1A? CD14? precursors, isolated from bone marrow and cultured in the presence of GM-CSF, also expressed both NKRP1A and CD14: these antigens were newly expressed on about one third of cells which had lost the CD34 precursor marker. In addition, NKRP1A was constitutively present on resting CD14+ peripheral blood Mo. When these cells were cultured in the presence of GM-CSF, the resulting DC population retained the expression of NKRP1A and acquired CD80, while they lost the CD14 antigen. Functional analysis revealed that the engagement of NKRP1A molecule leads to a strong intracellular calcium ([Ca2+]i) increase both in resting peripheral blood Mo and in vitro-derived DC. [Ca2+]i increase was mainly due to extracellular calcium influx, as it was completely abrogated by the addition of EGTA. More importantly, the engagement of the NKRP1A molecule induced interleukin (IL)-1β and IL-12 production by resting Mo and DC, respectively. Altogether these data indicate that NKRP1A lectin is present at the surface of Mo and DC and may play a relevant role in the activation and function of both cell types. 相似文献
26.
In experimental allergic encephalomyelitis (EAE), CD4+ T cells infiltrate the central nervous system (CNS). We derived CD4+ T cell lines from SJL/J mice that were specific for encephalitogenic myelin basic protein (MBP) peptides and produced both Th1 and Th2 cytokines. These lines transferred EAE to naive mice. Peptide-specific cells re-isolated from the CNS only produced Th1 cytokines, whereas T cells in the lymph nodes produced both Th1 and Th2 cytokines. Mononuclear cells isolated from the CNS, the majority of which were microglia, presented antigen to and stimulated MBP-specific T cell lines in vitro. Although CNS antigen-presenting cells (APC) supported increased production of interferon (IFN)-γ mRNA by these T cells, there was no increase in the interleukin (IL)-4 signal, whereas splenic APC induced increases in both IFN-γ and IL-4. mRNA for IL-12 (p40 subunit) was up-regulated in both infiltrating macrophages and resident microglia from mice with EAE. We have thus shown that a Th1 cytokine bias within the CNS can be induced by CNS APC, and that IL-12 is up-regulated in microglial cells within the CNS of mice with EAE. Microglia may therefore control Th1 cytokine responses within the CNS. 相似文献
27.
目的探究根治性膀胱癌切除术后感染切口愈合的危险因素及与单核淋巴细胞因子的关系。方法回顾性选取2015年1月-2018年12月于南阳市中心医院泌尿外科接受根治性膀胱癌切除术治疗的患者作为研究对象,共200例,根据术后切口是否发生感染分为感染组(n=100)和未感染组(n=100),其中感染组根据切口愈合时间分为早期愈合组(n=65)和延迟愈合组(n=35)。对影响根治性膀胱癌切除术后感染切口愈合的因素进行单因素和多因素Logistic回归分析;比较感染组和未感染组血清单核淋巴细胞水平。结果延迟愈合组患者术中出血量高于早期愈合组,白蛋白含量低于早期愈合组,手术时间长于早期愈合组,尿瘘、肠瘘次数均高于早期愈合组(均P<0.05)。经Logistic回归分析,白蛋白、术中出血量、手术时间、尿瘘、肠瘘是影响患者感染切口愈合的独立危险因素(P<0.05)。切口感染组血清肿瘤坏死因子-α(TNF-α)、粒细胞集落刺激因子(G-CSF)、白细胞介素-8(IL-8)、IL-4、IL-6水平高于未感染组(均P<0.05),而IL-2水平低于未感染组(P<0.05)。结论白蛋白、术中出血量、手术时间、尿瘘、肠瘘是影响患者感染切口愈合的独立危险因素,在临床上应采取有针对性的预防控制措施,避免影响术后切口的愈合。同时,对单核淋巴细胞因子的检测有助于防治术后切口感染的发生。 相似文献
28.
BACKGROUNDS: Hemangiomas are highly prevalent in newborns and infants and can lead to severe complications. However, the pathogenesis of hemangiomas is still unknown. This study was designed to examine the potential of human monocytes to differentiate into hemangioma endothelial cells. METHODS: Purified monocytes from adult human peripheral blood were cultured under a conditional culture environment supplemented with basic fibroblast growth factor and vascular endothelial growth factor. Cells cultured for 2 weeks were subjected to histological and immunochemical examinations in order to determine the expression of specific markers for hemangioma endothelial cells. RESULTS: Monocytes cultured for 2 weeks in angiogenic medium expressed human erythrocyte-type glucose transporter protein, FcgammaRII, and several other endothelial markers, all of which are deemed specific markers for hemangioma endothelial cells. However, neither CD133 nor alpha smooth muscle actin was detected in our monocyte culture. CONCLUSION: Our data suggested that monocytes are capable of differentiating into hemangioma endothelial cells under the angiogenic stimulation from microenvironment of proliferative hemangioma. 相似文献
29.
Paul R. Goodyer Jehane Fata Cynthia G. Goodyer 《Pediatric nephrology (Berlin, Germany)》1990,4(2):101-104
In Henoch-Schönlein purpura nephritis (HSPN), glomeruli may develop cellular crescents composed of infiltrating monocytes and proliferating renal epithelia. In this study, we demonstrate that peripheral human monocytes can release an epidermal growth factor (EGF)-like substance detectable by a radioreceptor assay, which recognizes both EGF and transforming growth factor-alpha (TGF-alpha), but not with a radioimmunoassay, which recognizes only EGF. Furthermore, we report that urine from pediatric patients during the acute phase of HSPN contains a similar EGF-like species in addition to the endogenous EGF which is normally present. The EGF-like material was not present in urine from nine healthy children or from six children with acute post-streptococcal glomerulonephritis. The extent of crescent formation in our patients is uncertain, since renal biopsy was performed in only one case. However, we speculate that the urinary material resembling TGF-alpha which appears during the acute phase of HSPN may derive from monocytes infiltrating the kidney. 相似文献
30.
Asai J Suzuki R Fujimoto T Suzuki T Nakagawa N Nagashima G Miyo T Hokaku H Takei A 《Clinical neurology and neurosurgery》1999,101(4):1139-234
Infiltration of brain neoplasms by mononuclear cells including monocytes/macrophages has attracted little attention since they have marked morphological heterogeneity. Twenty-seven meningiomas were studied by anti-CD68 antibody-gated flow cytometry and by immunohistochemical analysis using the anti-CD68 antibodies. Flow cytometric analysis divided cells contained within tumor tissues into CD68-positive and -negative cells. In addition, eight gliomas, eight metastatic brain tumor, and 12 pituitary adenomas were investigated in the same way to compare meningiomas. The mean contents of CD68-positive cells were 24.0±3.7% in meningiomas, 4.4±1.4% in gliomas, 9.5±3.9% in metastatic brain tumors, and 4.5±1.8% in pituitary adenomas. Immunohistochemically, CD68-positive cells showed significant heterogeneity and were detected as round, rod-shaped, ameboid and ramified cells in meningiomas. Although the infiltrated mononuclear cells in gliomas have been investigated to some degree and showed that they express cytokines and/or growth factors, these infiltrated cells in meningioma have barely been studied. The CD68-positive cells detected in this study are likely to be monocytes, macrophages and microglias, and are presumed to be in various functional stages and to play important roles in growth regulation in meningioma. 相似文献