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The CpG motif within bacterial DNA is a potent immuno-stimulatory moiety. Here, using a 2-D electrophoretic approach, we investigated the effect of synthetic oligodeoxynucleotide containing a B type CpG motif (CpG-B ODN) on the protein expression profile of swine peripheral blood mononuclear cells (PBMC). We found that several proteins including spondin 1, N-acetolactate alpha linked acidic dipeptidase; V kappa light chain, T cell receptor variable alpha chain, heat shock protein (Hsp) 60, Hsp70, KIAA0857 protein, and PNAS-146 were up-regulated in PBMC by CpG-B ODN stimulation. Further studies showed that CpG-B ODN-mediated Hsp60, Hsp70 and Hsp90 expressions were closely associated with the TLR9 signalling pathway. Pretreatment with inhibitors of Hsp70, Hsp90 and TLR9 all blocked the CpG-B ODN-mediated anti-apoptotic effect in swine PBMC. These results suggest that CpG-B ODN treatment of swine PBMC may enhance the expression of biologically active proteins, notably spondin 1, V kappa light chain, T cell receptor variable alpha chain and Hsps, which may play an important role in CpG-B ODN-mediated activation of immune responses and enhancement of swine PBMC survival. 相似文献
3.
基于三维重建技术的坡面细沟侵蚀演变过程研究 总被引:3,自引:1,他引:3
作为黄土高原地区沟头溯源侵蚀和水流汇集发源地的梁峁坡面,在强降雨下其产流产沙对沟缘线以下坡面及沟道侵蚀有着重大影响。该研究根据野外实地考查构建5°~35°变坡段实体模型,进行6场间歇性人工模拟降雨试验,并借助基于三维重建技术的PhotoScan软件获取坡面DEM,将其侵蚀演化过程进行图形化、数字化,定性定量揭示其侵蚀形态演变特征。研究表明:1)梁峁坡面细沟侵蚀历经4个阶段:面蚀阶段,即产生一系列呈串珠状分布的侵蚀跌坑,宽度5~9 cm,深度1~4 cm;细沟形成阶段,由面蚀所产生的微小跌坑在径流作用下长、宽、深均不断增大,最大分别达到266、7.6、13.8cm;细沟网形成阶段,细沟出现分叉及联通,有明显流路;小切沟形成阶段,伴随沟壁崩塌、沟壁加宽和沟底下切,最大沟长及最大沟深较细沟形成时增大3倍以上。2)对比次降雨过程基于三维建模所计算侵蚀量与实测侵蚀量,第1场降雨试验因地表疏松颗粒较多导致实测侵蚀量比建模计算侵蚀量大而引起较大偏差(20.82%),其他场次偏差均在10%左右或以下,总体来说,该技术可以较好地应用于侵蚀发育过程的研究。该研究实现侵蚀演变关键过程图形化、数字化,有助于人们定性、定量了解和认识梁峁坡面侵蚀过程,且对于创新侵蚀过程研究方法亦具有实践指导价值。 相似文献
4.
Although evaluations of the availability of cadmium (Cd) contaminants in phosphate fertilizers have been made, few have examined the transfer efficiency of Cd from fertilizers to plants, especially under field conditions. This 2-year field study determined the transfer of added Cd to lettuce (Lactuca sativa L.) (Royal Green) from a western phosphate rock (PR) and a triple superphosphate (TSP) as affected by liming and rate of fertilizer (or Cd) input. A readily soluble Cd salt, CdCl2, was included in the study for comparison. The cumulative amounts of Cd added from the fertilizers and CdCl2 over the 2-year period ranged from 0 to 1440 g ha–1. Lettuce yield increased with increasing TSP rates, but was unaffected by PR. Significant (P < 0.01) effects of Cd source and rate, lime, and year were found on Cd accumulation by lettuce. The transfer of the added Cd was consistently higher for CdCl2 than for the fertilizers regardless of lime rate. A contrasting year effect was also found between the two P fertilizers. In the second year of application, the Cd transfer efficiency increased in the soil treated with the PR, but decreased in the soil treated with the TSP. The Cd transfer efficiency for the plant was better measured with DTPA–Cd (r
2= 0.78 – 0.80) or CaCl2–Cd (r
2= 0.57 – 0.76) than with soil total Cd (r
2= 0.39 to 0.54) across all Cd sources and lime rates. This is because DTPA–Cd or CaCl2–Cd reflected the influences of the amount of Cd added, Cd source, and lime rate on Cd accumulation by the plant better than did the soil total Cd. Of the amount of Cd added from the fertilizers an average of 1.0% or less was accumulated in the harvested lettuce tissue. Applications of the fertilizers at high rates could result in increased Cd accumulation in the soil over time. 相似文献
5.
Taiwania (Taiwania cryptomerioides Hayata), native to Taiwan, is one of the most economically important tree species grown there. In this article we summarize
the current results of phytochemistry and bioactivity of Taiwania extracts, including antifungal, antitermite, antibacterial,
and antimite activities as well as cytotoxicity against three tumor cells. The resources of Taiwania are also addressed.
Received: January 23, 2002 / Accepted: March 8, 2002
Acknowledgment The authors thank the National Science Council of R.O.C. for financial support (NSC-90-2313-B-002-344).
Correspondence to:S.-T. Chang 相似文献
6.
7.
利用福建53年雨季(5~6月)66个常规气象站月降水资料、NCEP/NCAR月平均再分析格点资料及NOAA海温重建资料,使用经验正交函数分解(EOF)、奇异值分解(SVD)、相关分析等方法,分析福建雨季降水的时空分布特征,结果表明:福建雨季的降水在空间上表现一致,即全省旱或全省涝;但存在显著的空间非均匀分布的第二类分布特征,即南旱北涝或南涝北旱。通过分析南北不均匀分布异常年的同期、前期大气环流和海洋特征,发现南旱北涝年近地面层温度场分布呈显著的北冷南暖特征,西太平洋副热带高压偏西偏强,且位置偏南,副高北侧低层较强的西南风将暖湿水汽输送到较北位置,此时南海夏季风强度偏弱,赤道中东太平洋为异常冷水覆盖;前期冬季乌拉尔山阻高偏强、西太平洋副高面积偏大、强度偏强、西伸点偏西,赤道中东太平洋海温偏高而西风漂流区海温偏低。南涝北旱年则基本反之。研究结果揭示了福建省降水时空分布不均的气象基础,对农事安排与防旱抗涝工作具有指导意义。 相似文献
8.
根据2014年11月(秋季)和2015年5月(春季)在三门湾进行渔业资源调查以及同步调查的6个主要环境因子数据(水温、盐度、悬浮物、p H、溶解氧及化学需氧量等),对三门湾鱼类群落结构及其与6个主要环境因子的关系进行了研究。结果显示,共捕获鱼类33种,其中以季节性洄游种类和暖水性种类为主。春、秋季优势种各有5种,其中棘头梅童鱼、龙头鱼和孔虾虎鱼为共同优势种。应用非度量多维测度分析(NMDS)和单因子相似性分析(ANOSIM)可得,春、秋鱼类群落均可划分为2组,其中1组主要分布在湾内,而另1组主要分布在湾口,在不同站位组间均存在极显著差异。长度谱分析结果显示,鱼类群落长度谱的斜率和截距有明显的季节性差异。RDA分析结果表明,鱼类群落主要受温度、溶解氧、悬浮物和p H等环境因子影响。 相似文献
9.
S. L. Hsieh H. T. Chang C. H. Wu C. M. Kuo 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):527-546
The stearoyl-CoA desaturase cDNA in tilapia (Oreochromis mossambicus) was cloned by RT-PCR and RACE, and it was compared with those in grass carp, common carp and milkfish. Nucleotide sequence analysis revealed that the full length of cDNA (1172 bp) clone encompasses 1008 bp open reading frame (ORF) encoding 336 amino acid residues. The deduced amino acid sequence shares 78–82% identity with the teleosts and 64–66% with mammals compared, and like these fish, the cloned tilapia stearoyl-CoA desaturase amino acid sequence conserves three histidine cluster motifs (one HXXXXH and two HXXHH), which functioned as non-heme iron binding sites, essential for stearoyl-CoA desaturase activity. RT-PCR and Northern blot analysis reveal that tilapia stearoyl-CoA desaturase is expressed only in liver, but the stearoyl-CoA desaturase expression in multiple tissues was observed in milkfish, grass carp and carp. Further, the hormonal regulation of stearoyl-CoA desaturase gene expression was investigated by a single injection of 17β-estradiol and testosterone. The results showed that the administration of 17β-estradiol to tilapia led to a greater increase in desaturase activity than testosterone, and higher doses of steroids produced greater increases in enzyme activity. The comparative RT-PCR analysis showed that the stearoyl-CoA desaturase mRNA level increased significantly in 17β-estradiol treated animals, especially in the groups receiving a single injection of 50 mg 17β-estradiol. This was reflected in the decrease in the saturated fatty acids and the increase in the monounsaturated fatty acids. The proportion of the polyunsaturated fatty acids was not affected. 相似文献
10.
Chin-Chyuan Chang Zhi-Rong Wu Cheng-Shou Chen Ching-Ming Kuo Winton Cheng 《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):333-342
Levels of glucose, lactate, pO2, pCO2, HCO3−, TCO2, Na+, K+, Cl−, protein, and oxyhemocyanin in the hemolymph and its osmolality and pH were measured when tiger shrimp, Penaeus monodon (13.5 ± 1.5 g body weight), were individually injected with saline or dopamine at 10− 8, 10− 7, or 10− 6 mol shrimp− 1. Results showed that hemolymph glucose, lactate, pCO2, HCO3−, and TCO2 values increased from 2 to 4 h; hemolymph osmolality, Na+, and total protein had increased at 2 h; and hemolymph K+ decreased from 2 to 8 h after the dopamine injection. All physiological parameters returned to the control values 4–16 h after receiving dopamine. The dopamine injection also significantly decreased the oxyhemocyanin/protein ratio of P. monodon which occurred at 2 h, resulting from an elevation of hemolymph protein and a slight decrease of oxyhemocyanin. These results suggest that stress-inducing dopamine caused a transient period of modulation of energy metabolism, osmoregulation, respiration, and the acid–base balance in P. monodon in adapting to this environmental stress. 相似文献