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961.
AIM:To investigate the effect of oxidized α1-antitrypsin (Ox-AT) on interleukin 8 (IL-8) and monocyte chemotactic protein 1(MCP-1) production in cultured human bronchial epithelial (HBE) cells. METHODS:Plasma native α1-antitrypsin (N-AT) was purified from human plasma by 50% and 75% ammonium sulfate fractionation followed by glutathione and anion exchange chromatography. Ox-AT was prepared by incubating N-AT (0.5 g/L) with N-chlorosuccinimide in a 25-fold molar excess to N-AT in PBS at room temperature for 30 min. HBE cells were cultured in the presence of Ox-AT (0.5 g/L) for 4 h, 10 h and 24 h, and the levels of IL-8 and MCP-1 in the supernatant were assayed using respective DuoSet kits. The effect of NF-κB inhibitor Bay11-7082 on the inflammatory cytokine release induced by Ox-AT was also evaluated. RESULTS:Ox-AT concentration-dependently and time-dependently increased the production of IL-8 and MCP-1 in HBE cells. The concentrations of IL-8 and MCP-1 in HBE cells induced by 0.5 g/L Ox-AT at 4 h, 10 h and 24 h were significantly higher than those in blank control and N-AT groups. Ox-AT increased the activity of NF-κB in a dose-dependent manner. The proinflammatory effect of by Ox-AT was inhibited by NF-κB inhibitor Bay11-7082. CONCLUSION: Ox-AT is a strong proinflammatory factor for HBE cells. The mechanism is related to NF-κB signaling pathway activation. 相似文献
962.
《Communications in Soil Science and Plant Analysis》2012,43(7-8):1295-1321
The potential of Nostoc 9v for improving the nitrogen (N)2–fixing capacity and nutrient status of semi‐arid soils from Tanzania, Zimbabwe, and South Africa was studied in a laboratory experiment. Nostoc 9v was inoculated on nonsterilized and sterilized soils. Inoculum rates were 2.5 mg dry biomass g?1 soil and 5 mg dry biomass g?1 soil. The soils were incubated for 3 months at 27 °C under 22 W m2 illumination with a photoperiod of 16 h light and 8 h dark. The moisture was maintained at 60% of field capacity. In all soils, Nostoc 9v proliferated and colonized the soil surfaces very quickly and was tolerant to acidity and low nutrient availability. Cyanobacteria promoted soil N2 fixation and had a pronounced effect on total soil organic carbon (SOC), which increased by 30–100%. Total N also increased, but the enrichment was, in most soils, comparatively lower than for carbon (C). Nitrate and ammonium concentrations, in contrast, decreased in all the soils studied. Increases in the concentration of available macronutrients were produced in most soils and treatments, ranging from 3 to 20 mg phosphorus (P) kg?1 soil, from 5 to 58 mg potassium (K) kg?1 soil, from 4 to 285 mg calcium (Ca) kg?1, and from 12 to 90 mg magnesium (Mg) kg?1 soil. Positive effects on the levels of available manganese (Mn) and zinc (Zn) were also observed. 相似文献
963.
《Communications in Soil Science and Plant Analysis》2012,43(6):948-957
Frequency of boron (B) deficiency is increasing in rainfed systems, and hence there is a need to diagnose the deficiency. Colorimetric methods are still widely used in soil-testing laboratories in India for measuring B. Little information is available on the comparative evaluation of the colorimetric and inductively coupled plasma (ICP) methods for determining extractable B in soils. We describe results of the comparative evaluation of these methods for measuring extractable B in 57 soil samples with pH values ranging from 5.3 to 9.5. There was a significant correlation between B values determined by the two methods, and the correlation coefficient was greater for soil samples with pH in the neutral to alkaline range. Interaction between soil samples and methods (ICP or colorimetric) was significant except for soil samples in the pH range of 8.0 to 9.5. Precision for B determination was greater with the ICP than with the colorimetric method. 相似文献
964.
《Communications in Soil Science and Plant Analysis》2012,43(7):873-887
The objective of this study was to evaluate soil nutrient loading and depth distributions of extractable nitrogen (N), phosphorus (P), and potassium (K) after long-term, continuous annual surface applications of anaerobically digested class B biosolids at a municipal recycling facility in central Texas. Commercial forage production fields of coastal bermudagrass (Cynodon dactylon L.) were surface applied at 0, 20, 40, or 60 Mg dry biosolids ha?1 y?1 for 8 years. Application duration was evaluated in fields treated with 20 Mg dry biosolids ha?1 y?1 for 0, 8, or 20 years. Total soil loads of extractable inorganic N and P increased linearly with application rate, but only extractable P increased with duration. Neither total load nor soil distribution of extractable K was affected by biosolid applications. Mineralization of biosolid-derived organic N and P likely contributed to elevated concentrations of nitrate throughout the soil profile (0–110 cm) and orthophosphate in surface soils (0–40 cm). 相似文献
965.
利用Client/Server和Browser/Server两种模式建立了一套混合模式的行之有效的人事办公综合信息系统,不仅面向人事管理者和领导,而且要面向所有的教职员工、面向所有网站登陆及浏览者。根据权限的不同、需求的不同,所能接触到的内容各不相同,达到既方便单位的人事管理,又能满足教职工信息共享要求的目的。 相似文献
966.
白菜型油菜品种、自交系与甘蓝型油菜波里马细胞质雄性不育系杂交、回交至BC2F1,再用南方白菜型油菜自交系与BC2F1测交,花期研究测交后代育性变化规律及定株定时观察白菜型波里马细胞质雄性不育材料与29A、广丰A、阿油A三种白菜型细胞质雄性不育材料育性变化情况.结果表明,在26个测交后代中,雄性不育的占23.1%,恢复可育的占7.7%,介于两者之间或育性分离的占69.2%.在南方白莱型油菜中发现能完全恢复育性的自交系。白菜型波里马细胞质雄性不育材料的不育性较其他三种不育材料稳定.可为油蔬两用的南方白菜型油菜杂种优势利用提供新的不育源。 相似文献
967.
968.
Chatter R Ben Othman R Rabhi S Kladi M Tarhouni S Vagias C Roussis V Guizani-Tabbane L Kharrat R 《Marine drugs》2011,9(7):1293-1306
Neorogioltriol is a tricyclic brominated diterpenoid isolated from the organic extract of the red algae Laurencia glandulifera. In the present study, the anti-inflammatory effects of neorogioltriol were evaluated both in vivo using carrageenan-induced paw edema and in vitro on lipopolysaccharide (LPS)-treated Raw264.7 macrophages. The in vivo study demonstrated that the administration of 1 mg/kg of neorogioltriol resulted in the significant reduction of carregeenan-induced rat edema. In vitro, our results show that neorogioltriol treatment decreased the luciferase activity in LPS-stimulated Raw264.7 cells, stably transfected with the NF-κB-dependent luciferase reporter. This effect on NF-κB activation is not mediated through MAPK pathways. The inhibition of NF-κB activity correlates with decreased levels of LPS-induced tumor necrosis factor-alpha (TNFα) present in neorogioltriol treated supernatant cell culture. Further analyses indicated that this product also significantly inhibited the release of nitric oxide and the expression of cyclooxygenase-2 (COX-2) in LPS-stimulated Raw264.7 cells. These latter effects could only be observed for neorogioltriol concentrations below 62.5 μM. To our knowledge, this is the first report describing a molecule derived from Laurencia glandulifera with anti-inflammatory activity both in vivo and in vitro. The effect demonstrated in vitro may be explained by the inhibition of the LPS-induced NF-κB activation and TNFα production. NO release and COX-2 expression may reinforce this effect. 相似文献
969.
Field studies were conducted during 1993 and 1994 in the Imperial Valley, California and Maricopa, Arizona to examine relationships between densities of Bemisia tabaci (Gennadius) populations and cotton (Gossypium hirsutum L.) yields, and to estimate economic injury levels (EILs) for pest management application. Populations of B. tabaci were manipulated by applying different numbers of insecticide applications in replicated plots. Resulting insect populations and cotton lint yields were used to develop damage functions and to estimate EILs for all life stages in relation to variable cotton prices, insecticide costs, and pest control efficacy. Economic injury levels declined with increasing cotton prices and increased as the cost of control increased, however, these changes were relatively small, based on typical ranges in price and control costs. In contrast, the efficacy of control provided by insecticide applications had a large influence on EILs, with lower efficacies being associated with higher injury levels. We developed a multiple regression model that accounted for the dynamic changes in the EIL in relation to crop price, control costs, control efficacy, and potential yield. Based on average prices and reasonable control costs and efficacy, EILs ranged from 5.9–15.2 adults/leaf, 6.1–19.8 eggs cm−2, and 1.7–4.7 nymphs cm−2 of leaf area. Additional research is needed to more closely relate the costs of control to the suppression of insect populations, and to define economic thresholds that will enable pest managers to maintain pest populations below EILs. 相似文献
970.
FAM134B基因对肌内脂肪沉积有重要的调控作用,为了进一步了解FAM134B基因的结构与功能及其对山羊(Capra hirus)肉质的影响,本研究以川中黑山羊为实验动物,采用RT-PCR技术克隆了山羊FAM134B基因,并对核苷酸序列和氨基酸序列进行生物信息学分析,运用实时荧光定量PCR技术检测了FAM134B mRNA的表达情况,对肌肉组织中FAM134B mRNA表达与肌内脂肪(intramuscular fat,IMF)含量进行了关联分析。结果表明,山羊FAM134B基因(GenBank登录号:KF684947.1)cDNA全长1 071 bp,编码356个氨基酸,预测蛋白序列含有4个N-连接的糖基化修饰位点,20多个磷酸化位点;系统进化树分析显示,山羊FAM134B核苷酸序列与牛(Bos taurus)的相似性最高;荧光定量PCR分析表明,FAM134B在山羊的心、肝、脾、肺、肾、背最长肌和腿肌中均有表达,其中在肝脏的表达量最高,脾的表达量最低;相关分析显示:山羊背最长肌、腿肌中FAM134B mRNA表达与肌内脂肪含量呈显著正相关。研究结果显示,FAM134B基因可能对山羊肌内脂肪沉积起着重要的调控作用。本研究为进一步了解FAM134B基因的功能及其在反刍动物IMF代谢中的作用和营养调控机制提供一定基础资料。 相似文献