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71.
目的: 探讨缺氧预适应小鼠脑匀浆提取液(HP extract)对PC12细胞缺氧耐受性的影响。方法: 复制小鼠急性重复缺氧模型,制备HP extract。在培养PC12细胞中加入HP extract使其终浓度分别为0.2、0.8、3.2、6.4、12.8 g/L(HP组)。以同浓度正常小鼠脑匀浆提取液(N extract)作为对照组(N组)。缺氧(2%O2) 培养24、48、72 h后, 采用四唑盐(MTT)比色法检测各组细胞活力 (A570值)并检测缺氧24、48、72 h乳酸脱氢酶(LDH)透出率、缺氧24 h早期凋亡率(Annexin V-FITC/PI双染流式细胞仪检测)、缺氧72 h晚期凋亡率(Hoechst33258染色荧光显微镜检测)。结果: HP extract浓度低于6.4 g/L(包括6.4 g/L), 缺氧培养24 h时, HP组A570值显著高于同浓度N组, 其 LDH透出率显著低于同浓度N组。随缺氧时间延长, 高浓度HP extract逐渐失去细胞保护作用。至72 h时浓度高于6.4 g/L(包括6.4 g/L)HP extract有促细胞凋亡作用, 此时HP组A570值显著低于同浓度N组, 其LDH透出率和晚期凋亡率均显著高于同浓度N组。结论: 缺氧预适应小鼠脑匀浆提取液对PC12细胞缺氧耐受性的影响呈浓度依赖性和时间依赖性。 相似文献
72.
73.
Bilateral skin conductance was recorded from 8 male and 8 female cigarette smokers and from 8 male and 8 female nonsmoker control subjects on two different days. On one day smokers smoked a cigarette prior to the recording session and on the other they remained abstinent. Subjects also engaged in tasks designed to differentially involve the cerebral hemispheres. SCR asymmetry was measured using two different indices. During both the resting and task periods smokers had larger SCRs in their right than left hands following smoking. Unlike control subjects during the first recording session, smokers did not show task related changes in SCR asymmetry. During tasks smokers showed smaller SCRs in both hands following smoking than following abstinence. Changes in SCR asymmetry associated with smoking were seen in subjects who smoked more cigarettes, reported more subjective craving, were more introverted, and indicated a preference for cognitive processes and strategies associated with the left hemisphere. Results are discussed in terms of relative involvement of the cerebral hemispheres following smoking and smoking abstinence. 相似文献
74.
Objective: To investigate whether cockroach allergen extract can stimulate Protease-activated receptor 2 (PAR-2) expressed in mouse lung fibroblast.Materials: We established an immortalized lung fibroblast cell line, DM5, from PAR-2 deficient mice. By stable transfection with either an empty vector (DM5/EV) or an expression vector encoding mouse PAR-2 cDNA (DM5/Par2), a pair of lung fibroblast cell lines with or without functional PAR-2 expression were prepared.Treatment: The cells were exposed to cockroach allergen extract {up to 800 protein nitrogen unit (PNU)/ml}, trypsin (up to 100 nM), SLIGRL agonist peptide (up to 500 M), and trans-cinnamoyl-LIGRO agonist peptide (up to 400 M).Methods: The cells were loaded with Fluo-3 calcium indicator and mobilization of intracellular calcium with the stimuli was monitored by a fluorometric plate reader. Extracellular signal-regulated kinase (ERK) phosphorylation was examined by Western blot analysis using an anti-phospho ERK antibody.Results: The cockroach extract induced intracellular calcium transients in a concentration dependent manner in DM5/Par2 but not in DM5/EV. The activity was abolished when the cockroach extract was heat denatured or pre-incubated with PMSF (phenylmethanesulfonyl fluoride) prior to the assay. Concomitantly, ERK phosphorylation was seen in DM5/Par2 with the cockroach extract but not with a heat-denatured extract. The responses were sensitive to an inositol-1,4,5 triphosphate antagonist (2-APB) indicating that calcium was mobilized from intracellular store.Conclusions: Cockroach allergen extract can activate PAR-2 and thereby stimulate mouse lung fibroblasts likely through protease(s). The present study proposes a potential mechanism for cockroach antigens, similar to house dust mite antigens, in the etiology of respiratory diseases.Received 29 February 2004; returned for revision 12 April 2004; accepted by M. Katori 22 April 2004 相似文献
75.
Gordon B. Strom Richard N. Boswell Robert L. Jacobs 《The Journal of allergy and clinical immunology》1983,72(1):46-53
Thirty-four patients with a history of immediate hypersensitivity to the sting of the imported fire ant were evaluated in a study designed to compare the diagnostic usefulness of fire ant whole body extract (WBE) preparations with that of fire ant venom (IFAV). Ninety-one percent () of the hypersensitive patients skin tested with IFAV at a maximal concentration of 1:5 × 103, , demonstrated a wheat equal to or greater than the histamine control. Fifty-three percent () of the group were skin test positive to a WBE preparation. When the criteria for a positive skin test were relaxed, 82% of the hypersensitive group could be identified with the IFAWBE. A comparison of skin test results in sensitive patients revealed variability in the sensitivity of the WBE preparations utilized in the study. Leukocyte histamine release demonstrated a dose-response release of histamine with both IFAV and SIWBEa preparations. Specific venom antisera produced in rabbits identified a precipitin line of common identity in a gel-diffusion system containing IFAWBE and IFAV. This finding was verified by the competitive inhibition of IFAWBE with IFAV in a solid-phase radioimmunoassay system. Fire ant WBEs contain venom constituents and are effective diagnostic agents in up to 82% of patients with hypersensitivity to the sting of the imported fire ant. Marked variability in the responsiveness of sensitive patients to different WBE preparations mandates standardization of these diagnostic preparations. 相似文献
76.
Donald Barnett Brian A. Baldo Merlin E.H. Howden 《The Journal of allergy and clinical immunology》1983,72(1):61-68
Crude peanut protein fractions from raw and roasted peanuts were examined in the RAST with 10 sera from patients showing clinical peanut sensitivity. The radioactive uptake results, which were generally high, did not reveal any distinguishable pattern. Two commercially available peanut proteins, peanut lectin and phospholipase D, gave poor RAST responses. Three purified peanut proteins, α-arachin, conarachin I, and concanavalin A-reactive glycoprotein, all gave significant RAST results that were generally lower than those obtained with the crude extracts. The extent of RAST inhibition obtained with these materials was inversely related to their abundance in the total peanut protein. Crossed immunoelectrophoresis with extracts from raw and roasted peanut indicated the presence of 22 and 10 anodically migrating antigens, respectively. Sixteen IgE binding antigens were revealed for raw peanut and seven for roasted peanut after incubation with a mixed serum from the 10 patients in crossed radioimmunoelectrophoresis (CRIE) using 125I-labeled anti-IgE. CRIE plates treated with individual serum samples showed that all the patients had specific IgE for the major antigen peak, which has been tentatively identified as α-arachin. This major storage protein of peanut, which is known to be particularly heat resistant, may be of greater clinical significance than its apparently low RAST activity would seem to indicate. 相似文献
77.
目的:探究泽漆水提物对香烟烟雾(CS)所致的慢性阻塞性肺病(COPD)的保护作用及肺组织癌前病变相关蛋白的影响。方法:通过建立CS所致的COPD小鼠模型(60只),随机分为正常组、模型组、阳性药组(地塞米松2 mg·kg-1)及泽漆水提物低、中、高剂量组(1.875、3.75、7.5 g·kg-1)。采用高效液相色谱法(HPLC)测定泽漆水提物中相关成分;动物肺功能仪检测小鼠呼气末期暂停(EEP)、气道阻力(Penh)、50%肺活量呼吸时的呼气流量(EF50)等肺功能指标变化;高通量液相蛋白芯片技术检测小鼠肺泡灌洗液(BALF)中白细胞介素(IL)-2、IL-5、IL-18、IL-17A、IL-27等炎性因子水平变化;苏木素-伊红(HE)染色检测小鼠肺组织的病理变化;比色法测定小鼠肺组织中的丙二醛(MDA)、髓过氧化物酶(MPO)及谷胱甘肽过氧化物酶(GSH-Px)含量变化;实时荧光定量聚合酶链式反应(Real-time PCR)检测肿瘤坏死因子-α(TNF-α)、转化生长因子-β(TGF-β)、基质金属蛋白酶(MMP)-2、MMP-9及MM... 相似文献
78.
Alma Martelli Lorenzo Flori Era Gorica Eugenia Piragine Anella Saviano Giuseppe Annunziata Matteo Nicola Dario Di Minno Roberto Ciampaglia Ilenia Calcaterra Francesco Maione Gian Carlo Tenore Ettore Novellino Vincenzo Calderone 《Nutrients》2021,13(5)
Preservation of vascular endothelium integrity and functionality represents an unmet medical need. Indeed, endothelial dysfunction leads to decreased nitric oxide biosynthesis, which is prodromic of hypertension and hypercoagulability. In this panorama, the nutraceutical supplement Taurisolo®, a polyphenolic extract from Aglianico cultivar grape, rich in catechin and procyanidins, was evaluated as a vasoprotective, vasorelaxing, anti-hypertensive and anti-coagulant agent in: cell lines, isolated vessels, in vivo models of chronic hypertension and hypercoagulability, and in clinical tests of endothelial reactivity. Taurisolo® demonstrated to fully protect vascular cell viability from oxidative stimulus at 100 µg/mL and evoke vasorelaxing effects (Emax = 80.6% ± 1.9 and pEC50 = 1.19 ± 0.03) by activation of the Sirtuins-AMPK-pathway. Moreover, Taurisolo®, chronically administered at 20 mg/Kg/die in in vivo experiments, inhibited the onset of cardiac hypertrophy (heart weight/rat weight = 3.96 ± 0.09 vs. 4.30 ± 0.03), hypercoagulability (decrease of fibrinogen vs. control: p < 0.01) and hypertension (mean of Psys: 200 ± 2 vs. control 234 ± 2 mmHg) and improved endothelial function (Emax = 88.9% ± 1.5 vs. control 59.6% ± 3.6; flow-mediated dilation in healthy volunteers after 400 mg twice daily for 8 weeks vs. baseline: p = 0.019). In conclusion, Taurisolo® preserves the vascular function against ox-inflamm-ageing process and the consequent cardiovascular accidents. 相似文献
79.
80.
夹竹桃水提物灭螺活性研究 总被引:3,自引:0,他引:3
目的 研究夹竹桃水提物的灭螺活性。方法 测试水提物作用后钉螺的死亡率,用直线回归法进行量效和时效分析。结果 夹竹桃水提物灭螺的量效和时效关系分别为Y=95.4378D-21.2478和Y=21.32T-3.96,pH从5.5到8.5的范围内其活性随pH上升略有下降,室内贮存1年及100℃加热2h其活性基本不变。结论 夹竹桃水提物具有很强的灭螺活性。 相似文献