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1.
Lysosomal stability during phagocytosis of Aspergillus flavus spores by alveolar macrophages of cortisone-treated mice 总被引：8，自引：0，他引：8
Control mice and those treated with cortisone were exposed to aerosols of viable spores of Aspergillus flavus. Fifteen to 20 minutes later, animals were killed, and alveolar macrophages were obtained by tracheobronchial lavage. Electron-microscopic examination of these cells revealed that, whereas the lysosomes of control macrophages showed extensive attraction and fusion with the phagocytic membranes surrounding spores, the lysosomes of macrophages from animals treated with cortisone revealed little, if any, interaction. This diminished lysosomal response in forming phagocytic vacuoles may be important in the subsequent development of hyphal bronchopneumonia which frequently, occurs in cortisonetreated mice exposed to spores of A. flavus. 相似文献
2.
Heterocytolysis by macrophages activated by bacillus Calmette-Guérin: lysosome exocytosis into tumor cells 总被引：16，自引：0，他引：16
J B Hibbs 《Science (New York, N.Y.)》1974,184(135):468-471
The cytotoxic activity of activated macrophages against tumorigenic target cells appears to be mediated by lysosomal enzymes of activated macrophage origin. Lysosomes of activated macrophages are secreted directly into the cytoplasm of susceptible target cells, which subsequently undergo heterolysis. This reaction can be inhibited by agents which prevent the exocytosis of macrophage lysosomes (hydrocortisone) or which interfere with the action of lysosomal enzymes (trypan blue). 相似文献
3.
Walburger A Koul A Ferrari G Nguyen L Prescianotto-Baschong C Huygen K Klebl B Thompson C Bacher G Pieters J 《Science (New York, N.Y.)》2004,304(5678):1800-1804
Pathogenic mycobacteria resist lysosomal delivery after uptake into macrophages, allowing them to survive intracellularly. We found that the eukaryotic-like serine/threonine protein kinase G from pathogenic mycobacteria was secreted within macrophage phagosomes, inhibiting phagosome-lysosome fusion and mediating intracellular survival of mycobacteria. Inactivation of protein kinase G by gene disruption or chemical inhibition resulted in lysosomal localization and mycobacterial cell death in infected macrophages. Besides identifying a target for the control of mycobacterial infections, these findings suggest that pathogenic mycobacteria have evolved eukaryotic-like signal transduction mechanisms capable of modulating host cell trafficking pathways. 相似文献
4.
【目的】研究表面活性剂对加利利链霉菌Streptomyces galilaeus AF1菌株发酵的影响。【方法】利用单因素试验优化表面活性剂的添加种类、初步浓度及最佳添加时间,采用Box-Behnken试验和响应面分析对表面活性剂添加质量浓度进行组合优化。流式细胞仪测定细胞荧光强度,确定表面活性剂对AF1菌株细胞膜的影响。【结果】表面活性剂的最优添加质量浓度:吐温–80为8.95 g·L~(–1)、曲拉通X–100为2.09 g·L~(–1)、山梨醇为3.89 g·L~(–1),最优添加时间为接种后5 d;细胞膜透性测定结果表明,试验组的AF1菌株细胞荧光强度极显著高于对照组。【结论】试验得到的响应面模型对因变量的解释程度达94.89%,具有实际意义;添加最优表面活性剂组合后,加利利链霉菌AF1的细胞膜通透性极显著增大,间接导致胞内活性物质的外排量增加,提高了抗菌活性物质的生物合成量。 相似文献
5.
Differential lysosomal proteolysis in antigen-presenting cells determines antigen fate 总被引：2，自引：0，他引：2
Delamarre L Pack M Chang H Mellman I Trombetta ES 《Science (New York, N.Y.)》2005,307(5715):1630-1634
Antigen-presenting cells (APCs) internalize antigens and present antigen-derived peptides to T cells. Although APCs have been thought to exhibit a well-developed capacity for lysosomal proteolysis, here we found that they can exhibit two distinct strategies upon antigen encounter. Whereas macrophages contained high levels of lysosomal proteases and rapidly degraded internalized proteins, dendritic cells (DCs) and B lymphocytes were protease-poor, resulting in a limited capacity for lysosomal degradation. Consistent with these findings, DCs in vivo degraded internalized antigens slowly and thus retained antigen in lymphoid organs for extended periods. Limited lysosomal proteolysis also favored antigen presentation. These results help explain why DCs are able to efficiently accumulate, process, and disseminate antigens and microbes systemically for purposes of tolerance and immunity. 相似文献
6.
Roy D Liston DR Idone VJ Di A Nelson DJ Pujol C Bliska JB Chakrabarti S Andrews NW 《Science (New York, N.Y.)》2004,304(5676):1515-1518
Strategies for inhibiting phagolysosome fusion are essential for the intracellular survival and replication of many pathogens. We found that the lysosomal synaptotagmin Syt VII is required for a mechanism that promotes phagolysosomal fusion and limits the intracellular growth of pathogenic bacteria. Syt VII was required for a form of Ca2+-dependent phagolysosome fusion that is analogous to Ca2+-regulated exocytosis of lysosomes, which can be triggered by membrane injury. Bacterial type III secretion systems, which permeabilize membranes and cause Ca2+ influx in mammalian cells, promote lysosomal exocytosis and inhibit intracellular survival in Syt VII +/+ but not -/- cells. Thus, the lysosomal repair response can also protect cells against pathogens that trigger membrane permeabilization. 相似文献
7.
非离子表面活性剂改性土壤的制备及其对水中有机污染物的吸附研究 总被引：6，自引：0，他引：6
采用室内实验方法，研究了用非离子表面活性剂烷基酚与环氧乙烷缩合物Tx-7、Tx-15制备有机粘土及其对水中芳香族化合物硝基苯、卤代烃l，2-二氯乙烷的吸附作用：结果表明，Tx-7、Tx-15均能与天然蒙脱土结合，Tx-7在天然蒙脱土中的吸附量大于Tx-15；改性土壤对水中有机污染物的吸附能力明显大于天然蒙脱土，Tx-7改性土壤的吸附能力大于Tx-15改性土壤：Tx-7改性土壤和天然蒙脱土对有机物的吸附通过分配进行，吸附等温线可用Henry方程表示。 相似文献
8.
研究了土壤结合态稠环芳烃的生物降解过程。结果表明 ,微生物能够降解土壤中的稠环芳香烃化合物 ,稠环芳烃与土壤结合是妨碍其生物降解的主要因素 ,表面活性剂能够显著提高结合态的稠环芳烃被降解的比例。在30d左右时间内 ,土壤中稠环芳烃可以被降解至一个稳定水平。 相似文献
9.
为筛选出新的对油茶炭疽病菌(Colletotrichum gloeosporioides)、西瓜枯萎病菌(Fusarium oxysporum f.sp.Niveum)和水稻稻瘟病菌(Pyricularia grisea)3种常见植物病原菌有效的杀菌剂,采用菌丝生长速率法,研究了山苍子油主成分及其衍生物15种化合物对这3种常见植物病原菌的抑制效果。结果表明:15种化合物对3种植物病原菌的生长均表现出一定的抑制作用,而且随着质量浓度的升高,抑制作用增强。通过本试验从15种化合物中依次筛选出对油茶炭疽病菌、水稻稻瘟病菌和西瓜枯萎病菌的抑菌作用最强的分别为乙位紫罗兰酮、柠檬腈、鸢尾酮,其EC50依次为31.53,37.64,133.60 mg/L。油茶炭疽病菌、水稻稻瘟病菌经乙位紫罗兰酮、柠檬腈处理后,其菌体细胞相对渗透率明显增大,表明细胞膜发生了破坏;而西瓜枯萎病菌经鸢尾酮处理后细胞相对渗透率先增大后减少,表明细胞膜没有发生破坏。 相似文献
10.
为研究普洱茶抗炎症功效的机理,使用THP-1细胞经佛波脂(PMA)分化形成的巨噬细胞为细胞模型研究普洱茶对细胞免疫功能的调节作用。研究发现:(1)在使用普洱茶水提取物作用巨噬细胞后,脂多糖(LPS)诱导刺激巨噬细胞分泌的白细胞介素6(IL-6)的量显著降低,且呈剂量依赖性;(2)直接用茶水提取物处理巨噬细胞,普洱茶和红茶水提取物均可以刺激细胞分泌IL-6;(3)普洱茶的降低LPS刺激巨噬细胞分泌IL-6的效果与EGCG无关。这些结果提示,普洱茶等具有对IL-6的双向调节作用。 相似文献
11.
Donor-derived cells in the central nervous system of twitcher mice after bone marrow transplantation 总被引：9，自引：0，他引：9
P M Hoogerbrugge K Suzuki K Suzuki B J Poorthuis T Kobayashi G Wagemaker D W van Bekkum 《Science (New York, N.Y.)》1988,239(4843):1035-1038
The twitcher mouse is an animal model of galactosylceramidase deficiency, comparable to Krabbe's disease, a lysosomal storage disease in humans. As in most lysosomal storage diseases, neurological deterioration is a prominent feature of the disease in these mice. Transplantation of enzymatically normal congenic bone marrow was earlier found to result in prolonged survival and increased levels of galactosylceramidase in the visceral organs of twitcher mice. It is now reported that bone marrow transplantation results in increased galactosylceramidase levels in the central nervous system (CNS). Concomitantly, the levels of psychosine, a highly toxic lipid that progressively accumulates in the CNS of untreated twitcher mice, stabilized at much lower levels in the CNS of treated twitcher mice. Histologically, a gradual disappearance of globoid cells, the histological hallmark of Krabbe's disease, and the appearance of foamy macrophages capable of metabolizing the storage product were seen in the CNS. By immunohistochemical labeling it was demonstrated that these foamy macrophages were of donor origin. The infiltration of enzymatically competent, donor-derived macrophages was accompanied by extensive remyelination in the CNS. It is concluded that after bone marrow transplantation, donor-derived macrophages infiltrate the affected brain tissue and are capable of inducing a partial reversal of the enzyme deficiency. 相似文献
12.
土壤中苯系物在表面活性剂溶液中的解吸研究 总被引：1，自引：0，他引：1
选用阴离子表面活性剂十二烷基苯磺酸钠和十二烷基硫酸钠(LAS和SDS)，阳离子表面活性剂十六烷基三甲基氯化铵(CTAB)和非离子表面活性剂(AEO-9和SA-20)对污染土壤进行解析试验。研究了用表面活性剂解吸土壤中的苯系物，从而为淋滤冲洗被石油污染的农田提供理论依据。试验表明，阴离子表面活性剂对苯系物的去除效率达95％，非离子表面活性剂对苯系物的去除率达85％，而阳离子表面活性剂无明显去除效果。 相似文献
13.
In the Chediak-Higashi syndrome, an anomalous hypopigmentation is associated with large lysosomal granules in the blood leukocytes. Since the inheritance pattern is that of an autosomal recessive trait, we postulated a common mechanism for these two primary features of the disease. Electron microscopy of melanocytes revealed that the pigmentary anomaly is indeed based on giant melanosomes. Since both types of granules, leukocytic and melanosomal, are characterized by limiting membranes, Chediak-Higashi disease may be a genetic disease of membranes. 相似文献
14.
在研究硝基苯和表面活性剂在土壤中吸附行为的基础上,探讨了表面活性剂对硝基苯在土壤中吸附的影响,并研究了不同表面活性剂对硝基苯污染土壤的增效修复效果。结果表明：i）在0—25mg·L^-1。浓度范围内,硝基苯在土壤中的吸附量与溶液中平衡浓度之间存在较好的线性关系,硝基苯在土壤中的吸附是以分配作用为主。ii）CTAB、SDBS和Tween80在土壤中的吸附等温线均近似为S形．且都在各自临界胶束浓度附近达到饱和吸附,饱和吸附量顺序为CTAB〉〉SDBS〉Tween80。一定浓度的硝基苯可以增加表面活性剂在土壤中的饱和吸附量。iii）在较低浓度的表面活性剂存在下,硝基苯的吸附量随着表面活性剂浓度升高而升高,而在高浓度表面活性剂存在下硝基苯吸附量随表面活性剂浓度升高而降低,其中SDBS对硝基苯吸附量的降低效果最为明显。iv）当应用表面活性剂对硝基苯污染土壤进行增效修复时,SDBS的修复效果最为显著。 相似文献
15.
16.
表面活性剂在土壤中的环境行为及其危害性分析 总被引：5，自引：0，他引：5
探讨了表面活性剂在土壤中的环境行为,主要介绍了表面活性剂在土壤的吸附行为和生物降解行为。综述了表面活性剂对土壤性质的影响,分析了土壤中表面活性剂大量存在时对陆生植物、动物、人体以及微生物的危害。认为全面了解表面活性剂环境安全性对推动表面活性剂工业的持续发展具有重大意义。 相似文献
17.
助剂Quad7对除草剂烟嘧磺隆增效作用的研究 总被引：3，自引：1，他引：2
利用3种不同助剂,通过温室盆栽试验与田间试验相结合的方法,研究了Quad7、农药生物增效剂、非离子表面活性剂对烟嘧磺隆活性的影响。试验结果表明,在相同喷液量条件下,处理35、50、70 ga.i.hm-2加Quad7比不加防效分别提高15%、11%、4%;3种助剂对烟嘧磺隆增效强度分别为Quad7增效15%,农药生物增效剂增效9%,非离子表面活性剂增效7%;使用Quad7可以降低喷液量,提高药效。 相似文献
18.
表面活性剂对乙烯菌核利光解的影响 总被引：2，自引：0，他引：2
研究了6种表面活性剂对乙烯菌核利在液相和固相表面光解的影响.结果表明,高压汞灯下,表面活性剂对乙烯菌核利液相光解的光猝灭效应随其添加浓度的不同而存在显著差异;但在玻片表面上,不同添加浓度对光猝灭效应的影响差异较小.太阳光下,SLS、SLBS、CTAB和S-20对乙烯菌核利的液相光解表现为光敏化效应;但在玻片上,只有SDS表现为光敏化效应. 相似文献
19.
有机硅助剂对莠去津增效作用的研究 总被引：9，自引：0，他引：9
通过室内理化指标测定及温室盆栽和大田试验,研究了有机硅助剂对莠去津的增效作用,并探讨了有机硅助剂对莠去津增效作用的机制.结果表明,有机硅助剂混用于莠去津后对阔叶杂草均有明显的增效作用,且用量最低,仅为喷液量的0.1%,有机硅助剂2#增效作用最明显,莠去津900 g a.i.·hm-2加入有机硅助剂2#后可增加防效40%... 相似文献
20.
为研究自噬抑制细胞焦亡对脓毒症肺损伤的保护作用,研究先于体外使用盲肠内容物刺激小鼠腹腔巨噬细胞使其发生炎性反应,通过乳酸脱氢酶检测法、酶联免疫吸附(ELISA)法及Western blottin法检测雷帕霉素激活自噬对巨噬细胞发生细胞焦亡的影响。结果发现激活自噬能降低巨噬细胞炎性小体的活化及炎性细胞因子的释放,抑制细胞焦亡。随后对健康C57小鼠构建脓毒症模型,观察雷帕霉素预处理对各组小鼠死亡率的影响,并通过Western blotting检测肺组织中LC3蛋白表达变化,HE染色观察肺组织形态学改变,发现雷帕霉素预处理能够减轻脓毒症小鼠肺组织病理损伤,降低小鼠死亡率。结果表明自噬能够抑制细胞焦亡,对降低脓毒症急性肺损伤具有重要意义。 相似文献