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51.
摘要 目的:探讨SOCE对百草枯(PQ)致肺纤维化过程的具体调控作用。方法:体外培养肺泡上皮A549细胞,设置分组为对照组、PQ组和PQ+SKF96365组。对照组不作任何处理;PQ组给予800 μM的PQ溶液处理细胞24 h;PQ+SKF96365组先加入10 μM的SKF96365预处理细胞2 h,然后再加800 μM PQ处理24 h。免疫荧光检测PQ染毒后SOCE相关蛋白的活化和胞内分布、NFATc1的表达和入核情况。清洁级小鼠40只,随机分为空白对照组、PQ组、SKF96365组和PQ+SKF96365组。PQ组及PQ+SKF96365组给予百草枯(20 mg/kg)一次性腹腔注射,对照组给予等量生理盐水;SKFS96365组及PQ+SKF96365组每天腹腔注射一次10 mg/kg的SKF96365溶液,持续3天,行HE染色、Masson染色观察肺组织病理状态改变以及胶原纤维的变化情况。结果:与正常组相比,PQ染毒组STIM1蛋白活化出现寡聚化现象并且ORAI1、TRPC1膜定位显著;PQ引起细胞质内NFATc1信号向细胞核内转移,密度差异具有统计学意义(P<0.01),使用SOCE抑制剂后NFATc1信号减弱向细胞质内转移(P<0.01)。与对照组相比,PQ中毒的小鼠肺泡结构被破坏,肺间质大量胶原纤维沉积;与PQ组相比,PQ+SKF96365组肺泡结构相对完整并且间质胶原纤维沉积减少。结论:PQ中毒可活化SOCE并通过增加NFAT入核激活下游转录信号,促进肺纤维化的发生。 相似文献
52.
《Biotechnic & histochemistry》2013,88(4):191-196
Pieces of mammalian nerves 1 to 2 cm. long were placed under moderate tension and fixed 24–48 hours in: picric acid, saturated aqueous, 90 ml.; formalin, 10 ml.; and trichloracetic acid, 25% aqueous, 2 ml. They were washed in water, cut in two and one end stained with 0.04–0.06% osmic acid solution, while the other was dehydrated, embedded in paraffin, and mounted sections from it stained with protargol. The fixing solution used was selected from a number of combinations of acidified picro-formalin as the one most likely to give satisfactory results when followed by both silver and osmic acid. The use of osmic acid solutions of less than 0.1% concentration avoided the overstaining of myelin sheaths seen frequently when stronger solutions were used with material that had been fixed previously. Protargol, 0.5% solution with fast green FCF added to make 0.05% dye in the final concentration, was used to impregnate sections for axis cylinders. Reduction and toning were done as in Bodian's method. 相似文献
53.
《Biocatalysis and Biotransformation》2013,31(1):77-86
Continuous asymmetric reduction of 4-oxoisophorone by the thermophilic bacterium Thermomonospora curvata JTS321 was examined using three reactor systems: packed bed, fluidized bed and hollow fiber. T. curvata was immobilized in polyacrylamide-hydrazide gels when used in the packed and fluidized bed reactors. Of the three reactor systems, the highest productivity (964 mg.1-1.h-1) was observed in the fluidized bed reactor. However, many cells grew outside of the gel matrix, causing product contamination. The productivity of the hollow fiber reactor was 504 mg.1-1.h-1; the problem of cell contamination of the product was avoided, as the molecular cut-off of the hollow fibers (400 000) was of an appropriate size to prevent cell leakage to the product stream. We therefore consider that the hollow fiber reactor is most suitable for continuous microbial conversions. 相似文献
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Cotton plant is one of the most important economic crops in the world which supplies natural fiber for textile industry. The crucial traits of cotton fiber quality are fiber length and strength, which are mostly determined by the fiber elongation stage. Annexins are assumed to be involved in regulating fiber elongation, but direct evidences remain elusive. Recently, we have investigated the activities of fiber-specific expressed annexins AnGb5/6 and their interacted proteins in cotton. AnGb5 and 6 can interact reciprocally to generate a protein macro-raft in cell membrane. This macro-raft is probably a stabilized scaffold for Actin1 organization. The actin assembling direction and density are correlated with AnGb6 gene expression and fiber expanding rate among three fiber length genotypes. These results suggest that annexins may act as the adaptor that linked fiber cell membrane to actin assembling. Due to the strong Ca2+ and lipid binding ability of annexins, these results also indicate that annexins complex may function as an intermediate to receive Ca2+ or lipid signals during fiber elongation. 相似文献
59.
《Cell calcium》2020
In response to excitation of skeletal muscle fibers, trains of action potentials induce changes in the configuration of the dihydropyridine receptor (DHPR) anchored in the tubular membrane which opens the Ca2+ release channel in the sarcoplasmic reticulum membrane. The DHPR also functions as a voltage-gated Ca2+ channel that conducts L-type Ca2+ currents routinely recorded in mammalian muscle fibers, which role was debated for more than four decades. Recently, to allow a closer look into the role of DHPR Ca2+ influx in mammalian muscle, a knock-in (ki) mouse model (ncDHPR) carrying mutation N617D (adjacent to domain II selectivity filter E) in the DHPRα1S subunit abolishing Ca2+ permeation through the channel was generated [Dayal et al., 2017]. In the present study, the Mn2+ quenching technique was initially intended to be used on voltage-clamped muscle fibers from this mouse to determine whether Ca2+ influx through a pathway distinct from DHPR may occur to compensate for the absence of DHPR Ca2+ influx. Surprisingly, while N617D DHPR muscle fibers of the ki mouse do not conduct Ca2+, Mn2+ entry and subsequent quenching did occur because Mn2+ was able to permeate and produce L-type currents through N617D DHPR. N617D DHPR was also found to conduct Ba2+ and Ba2+ currents were strongly blocked by external Ca2+. Ba2+ permeation was smaller, current kinetics slower and Ca2+ block more potent than in wild-type DHPR. These results indicate that residue N617 when replaced by the negatively charged residue D is suitably located at entrance of the pore to trap external Ca2+ impeding in this way permeation. Because Ba2+ binds with lower affinity to D, Ba2+ currents occur, but with reduced amplitudes as compared to Ba2+ currents through wild-type channels. We conclude that mutations located outside the selectivity filter influence channel permeation and possibly channel gating in a fully differentiated skeletal muscle environment. 相似文献
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