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1.
850 nm微激光已被发现能够减少黑色素细胞内酪氨酸酶的表达,进而抑制黑色素的合成。在此基础上本文选用C57BL/6J小鼠为模型,采用拉曼光谱法和荧光光谱法初步研究了850 nm微激光的在体美白效应。黑色素含量丰富时,小鼠皮肤拉曼谱线中代表黑色素的信号(1 405 cm-1和1 609 cm-1)变得异常明显;而经过微激光的照射后这些拉曼信号明显减弱。在NIR光的激发下黑色素也能发出强烈的荧光,这种荧光信号也会因微激光的照射而减弱。通过计算相对的拉曼信号强度及荧光信号强度对850 nm微激光的美白效应进行了定量分析。最后,采用常规的组织学检测(HE染色和Fontana-Masson染色)验证了光谱学检测手段的有效性。因此,光谱学技术可以作为一种简单有效的方法用于黑色素相关生理事件的实时检测。  相似文献   

2.
IgE介导的肥大细胞脱颗粒信号转导途径的研究进展   总被引:1,自引:0,他引:1  
肥大细胞(mast cell,MC)是过敏性疾病的关键细胞之一.机体的过敏反应很大程度依赖于肥大细胞膜上的特异性受体FcεRI.肥大细胞膜上交联的FcεRI引发了下游的一系列信号事件并导致脱颗粒,包括细胞因子及趋化因子产生以及白三烯的释放.由于IgE在过敏反应中的重要作用,现在的研究主要集中在FcεRI下游的信号事件.其脱颗粒的分子机制是一个由多种蛋白质分子介导的,各个环节受到精确调控的复杂过程.对肥大细胞脱颗粒分子机制的深入研究将给过敏性疾病提供一个新的治疗方案.  相似文献   

3.
目的:探讨脱钙对鼠颅骨标本中肥大细胞组织化学与免疫组织化学染色影响.方法:用不同脱钙液处理小鼠颅骨标本,组织切片后进行苏木素一伊红染色、甲苯胺蓝染色、醛品红染色以及免疫组织化学染色.结果:经过不同脱钙液处理后的颅骨组织切片组织结构保存完好,肥大细胞的组织化学染色(甲苯胺蓝和醛品红染色),及肥大细胞中胰蛋白酶的免疫组织化学染色清晰.结论:不同脱钙液(8%盐酸脱钙液、EDTA脱钙液、混合酸脱钙液)处理不影响鼻腔粘膜中肥大细胞的组织化学和免疫组织化学染色.  相似文献   

4.
He-Ne激光照射对血液及其组分荧光光谱影响的实验研究   总被引:2,自引:0,他引:2  
为研究弱激光照射对人血液携氧能力的影响及机制,我们用荧光仪分别测量了He-Ne激光照射前后正常血液及其组分(血浆、红细胞)的荧光光谱,研究了激光照射导致的光谱变化,并分析了光谱变化与血液携氧能力改变的关系。实验结果显示:全血液标本在490nm及614nm附近有荧光峰值;血浆的荧光则主要分布在420-500nm之间;红细胞在500nm及614nm附近有荧光。He-Ne激光照射后,全血液及红细胞在614nm处的荧光谱都有较明显的变化,且较相似。由此可得出结论,He-Ne激光照射可影响血液的携氧能力。  相似文献   

5.
天花粉对小鼠子宫肥大细胞超微结构的影响   总被引:1,自引:0,他引:1  
本研究用雌性中国1号小鼠12只,分实验组和对照组,实验组分别腹腔注射天花粉后处死,取子宫组织作超薄切片,电镜观察。在天花粉作用下,常见子宫肥大细胞脱颗粒,呈功能活化状态,并与子宫平滑肌细胞紧密相邻。提示肥大细胞可能通过脱颗粒释放组胺促进子宫平滑肌的收缩。同时,也见肥大细胞与子宫结缔组织中的成纤维细胞,淋巴细胞等密切接触,提示成纤维细胞和淋巴细胞与天花粉作用下子宫肥大细胞的数量增多有关。  相似文献   

6.
510.6nm激光照射对兔血管平滑肌细胞增殖的影响   总被引:2,自引:0,他引:2  
本文用510.6nm 波长激光以功率密度1、5、10 m W/cm 2 和能量密度2、4、6J/cm 2 照射体外培养的兔血管平滑肌细胞(SMC),通过3H- TdR掺入率和细胞生长曲线测定细胞增殖率。结果显示,上述激光照射量均能抑制细胞增殖率,其中以10m W/cm 2 组的作用最为显著  相似文献   

7.
本文概述了近年来激光微束在染色体微切割和微分离、分子细胞生物学、去除细胞壁、诱导原生质体融合等方面的应用,并对其今后的应用前景作了展望。  相似文献   

8.
XeCl准分子激光辐照对溶菌酶结构的影响   总被引:1,自引:0,他引:1  
利用荧光光谱、SDS-PAGE和NMR方法,考察308 nm XeCl准分子激光辐照对溶菌酶结构与活性的影响。使用能量密度为0.3 mJ/mm2的激光辐照溶菌酶,脉冲数分别为25、50、100、200、600、1200、1800、3600和7200。结果表明,用低强度激光辐照(低于200个脉冲)时,溶菌酶的活性出现增高趋势。随着激光辐照脉冲数的进一步增大,溶菌酶的活性又开始逐步降低。激光辐照处理后,溶菌酶的荧光强度发生了与生物活性相对应的先增高再降低现象,说明溶菌酶的高级结构发生了显著变化。SDS-PAGE结果显示,经激光辐照后,溶菌酶出现了分子间的聚合。分析溶菌酶的1H-NMR谱发现,辐照后,溶菌酶色氨酸(Trp)111、Trp63和Trp62的化学位移发生了变化,此结果进一步说明,激光辐照使溶菌酶的高级结构发生了变化。该实验可为激光辐照诱导蛋白质去折叠的研究提供参考。  相似文献   

9.
为研究山茱萸中抗过敏活性成分,采用透明质酸酶抑制实验对山茱萸中活性组分进行初步筛选;采用细胞脱颗粒抑制实验对透明质酸酶抑制活性较高的组分进一步评估;采用气相色谱-质谱联用法(GC-MS)进行成分分析。结果表明山茱萸石油醚部位(petroleum ether extract of Corni Fructus,COPE)具有显著透明质酸酶抑制活性,其IC50值为3.11 mg/mL;经硅胶柱层析分离得到4个透明质酸酶抑制活性更高的组分,其中组分COPE-8对RBL-2H3细胞脱颗粒抑制作用更显著,呈剂量依赖形式且具低细胞毒性。经20μg/mL COPE-8处理后,RBL-2H3细胞脱颗粒释放的组胺和β-氨基己糖苷酶分别减少46%和39%;经GC-MS分析,COPE-8中主要活性物质为萜类物质,包括α-香树脂醇、β-香树脂醇和香紫苏醇。结果表明COPE-8具有显著的抗过敏活性,在抗过敏活性物开发方面具有一定的应用价值。  相似文献   

10.
鼠脑微透析液痕量氨基酸的激光诱导荧光检测   总被引:3,自引:0,他引:3  
使用自制微透析探针和活动体位生化取样装置以及自行组装的毛细管电泳-增强型电荷耦合器件-激光诱导荧光系统,对鼠脑透析液中的痕量氨基酸以异硫氢酸荧光黄(FITC)进行柱前衍生后进行了分离和检测. 鼠脑海马CA3区微透析液中游离氨基酸的浓度为10-8~10-6 mol/L, 并将其用于学习与记忆的研究, 为无损伤研究活体脑内神经递质和其他痕量生化物质的动态变化提供了一种新方法.  相似文献   

11.
目的:研究850 nm波长微激光对肥大细胞照射后胞内钙离子浓度的影响。方法:实验前12 h,将肥大细胞接种于激光共聚焦专用培养皿中,然后用D-Hank’s液洗涤3次,加入2 m L D-Hank’s液,按照照射时间不同共分六组(Control,1 min,2 min,2.5 min,3 min,4 min),其中,空白对照组不进行激光照射处理;激光照射后,弃去D-Hank’s液,加入含有Fluo-3/AM的D-Hank’s液1 m L,放入培养箱中孵育30 min后,用D-Hank’s液洗涤3次去除胞外多余的Fluo-3/AM,再加入含有10%FBS的D-Hank’s液2 m L,置激光扫描共聚焦显微镜检测。结果:空白对照组中细胞内未见荧光,说明此时胞内无钙离子,但从1 min开始在细胞中发现荧光,而且发现随着照射时间的加长,其荧光强度越来越强,这可能与微激光照射时间越长从而刺激胞内出现更多的钙离子有关。从上面的实验说明850 nm微激光能作为仿灸仪器的光源。  相似文献   

12.
Protease-activated receptors (PARs) belong to a family of G-coupled seven transmembrane receptors that are activated by a proteolytic cleavage of their N-termini. Recent studies suggest the involvement of protease-activated receptors-1 and -2 (PAR-1, PAR-2) activators in mast cell de-granulation in various physiological and pathophysiological processes in inflammatory responses. Although PAR-1 and PAR-2 activating proteases, thrombin and tryptase, have been associated with mast cell activation, PAR-1 and PAR-2 have not been localized within these cells. We describe here the localization of PAR-1 and PAR-2 in mast cells from various normal human tissues using im-munohistochemical and double immunofluorescence techniques. The presence of these receptors on the membrane may explain the actions of accessible extracellular thrombin and tryptase for mast cell activation. In addition to the membrane labeling, these receptors are also localized on the membrane of the intracellular tryptase-positive granules, which may function to sustain further mast cell degranulation upon exocytosis. The localization of these two receptors in mast cells suggests a novel mechanism for controlling mast cell activation through regulation of PARI and PAR-2.  相似文献   

13.
Mast cells play important roles in allergic disease and immune defense against parasites. Once activated (e.g. by an allergen), they degranulate, a process that results in the exocytosis of allergic mediators. Modulation of mast cell degranulation by drugs and toxicants may have positive or adverse effects on human health. Mast cell function has been dissected in detail with the use of rat basophilic leukemia mast cells (RBL-2H3), a widely accepted model of human mucosal mast cells3-5. Mast cell granule component and the allergic mediator β-hexosaminidase, which is released linearly in tandem with histamine from mast cells6, can easily and reliably be measured through reaction with a fluorogenic substrate, yielding measurable fluorescence intensity in a microplate assay that is amenable to high-throughput studies1. Originally published by Naal et al.1, we have adapted this degranulation assay for the screening of drugs and toxicants and demonstrate its use here.Triclosan is a broad-spectrum antibacterial agent that is present in many consumer products and has been found to be a therapeutic aid in human allergic skin disease7-11, although the mechanism for this effect is unknown. Here we demonstrate an assay for the effect of triclosan on mast cell degranulation. We recently showed that triclosan strongly affects mast cell function2. In an effort to avoid use of an organic solvent, triclosan is dissolved directly into aqueous buffer with heat and stirring, and resultant concentration is confirmed using UV-Vis spectrophotometry (using ε280 = 4,200 L/M/cm)12. This protocol has the potential to be used with a variety of chemicals to determine their effects on mast cell degranulation, and more broadly, their allergic potential.  相似文献   

14.
肥大细胞作为主要的免疫细胞之一,不仅参与机体过敏、炎症,组织损伤修复、免疫等反应,还与很多生理病理过程有关.它的分化、成熟、激活和介质的释放都受到严格的调控.对肥大细胞的深入研究既可以使我们更加透彻地了解过敏、炎症和免疫性疾病的机理,也可以为此类疾病的预防和治疗提供有价值的参考和借鉴.  相似文献   

15.
肥大细胞的组织化学与超微结构异质性   总被引:3,自引:0,他引:3  
肥大细胞(mast cell,MC)是一种重要的免疫细胞,分为结缔组织肥大细胞(connective tissue mast cell,CTMC)和黏膜肥大细胞(mucosal mast cell,MMC)两大类。肥大细胞具有异质性,即肥大细胞在不同种属或同一种种属的不同个体、甚至同一种个体的不同组织器官中存在着形态学、分布、颗粒化学成分、染色特性及超微结构和功能等方面的差异性。近些年,人们围绕着肥大细胞的异质性进行了一系列生物学研究,并取得了一定进展,但对异质性的机制认识尚不清楚。深入的讨论、研究与比较仍然很必要。现对肥大细胞的亚群、形态与分布、着染性与免疫组化、超微结构等的异质性研究进展作一简要综述。  相似文献   

16.
Metabolic inhibitors can clearly affect different aspects of the functional activity of cells. This property was studied in the present work with respect to MK-886, a well-known inhibitor of the 5´-lipoxygenase-activating protein. It was found that this inhibitor in a micromolar concentration range (2-20 µM) induced in a dose-dependent manner H2O2 generation by human neutrophils and the release of lysozyme from the cells. The MK-886-induced activation of neutrophils was accompanied by a significant decrease in N-(1-pyrene)maleimide-accessible SH-groups in the cells. According to its activity, MK-886 can be considered an agonist that causes up-regulation of inherent neutrophil functions. In summary, the results indicate that during the application of MK-886 as a 5´-lipoxygenase inhibitor in neutrophils, the impact of the compound on the functional activity of the cells should be taken into consideration.  相似文献   

17.
Isolated rat peritoneal mast cells actively secrete histamine in response to reaginic or chemical stimulation. Mast cells were irradiated in a waveguide microwave exposure chamber at 2450 MHz with power absorptions of 8.2 and 41.0 mW/g for periods up to 3 h. These levels of microwave absorption caused no change in the morphological characteristics or viability of the cells. Irradiated mast cells were stimulated with compound 48/80, a potent, noncytotoxic histamine releasing agent. The dose response curves showed that neither prior nor simultaneous irradiation of mast cells at 37°C affected 48/80-induced secretion. However, microwave power absorptions of 41.0 mW/g inhibited secretion at 44.0°C. Precise measurements of the effect of heat on secretion indicated that this level of inhibition could have been produced by a radiation induced increase in cell temperature between 0.4 and 0.9°C above ambient levels. Alternatively, the heat stress produced at 44°C may have sensitized the cells to the electromagnetic effects of the microwave radiation. Rat peritoneal mast cells can therefore be useful as a model for the study of functioning secretory cells during microwave irradiation and can also be used to monitor the synergistic effects of cell heating during in vitro exposure.  相似文献   

18.
Mast cells have been reported to be predominant in the vaginal smears of patients infected with T. vaginalis. In this study, we investigated whether T. vaginalis could induce mast cells to migrate and to produce TNF-alpha and histamine. Rat peritoneal mast cells (RPMC), a primary mast cell, were used for the study. T. vaginalis induced an increase in chemotactic migration of the mast cells toward excretory and secretory product (ESP) of T. vaginalis, and the mast cells activated with T. vaginalis showed an increased release of histamine and TNF-alpha. Therefore, mast cells may be involved in the inflammatory response caused by T. vaginalis.  相似文献   

19.
肥大细胞是人体主要免疫细胞之一,因其作为导致过敏反应发生的最直接效应细胞而著称.肥大细胞最主要的结构特征为其胞内含有大量嗜碱性颗粒,该颗粒内又富含种类众多的生物活性物质,包括组胺、血管内皮生长因子(vascular endothelial growth factor,VEGF)、成纤维细胞生长因子(fibroblast...  相似文献   

20.
We investigated the effects of geranium essential oil (GEO) on anaphylaxis. GEO can exert antioxidant and anti-inflammatory effects, but its roles in allergic reactions are incompletely understood. Here, we used mouse cells to show that GEO inhibited the degranulation of cultured mast cells (CMCs). Citronellol is the major component of GEO and inhibited CMC degranulation. The l-enantiomer of citronellol more effectively suppressed CMC degranulation than did d-citronellol. We also examined whether citronellol could inhibit the immunoglobulin (Ig) E-induced production of tumor necrosis factor (TNF)-α. Treatment with various concentrations of citronellol before CMC activation with IgE significantly inhibited the induction of TNF-α in a dose-dependent manner. Mechanistically, citronellol suppressed the phosphorylation of mitogen-activated protein kinase (ERK), which is critical for ERK activation and the production of inflammatory cytokines in mast cells. These findings suggest that citronellol may represent a candidate compound for the effective treatment of allergic diseases.  相似文献   

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