中高纬度森林地区由于气候条件变化剧烈,土壤温室气体排放量的估算存在很大的不确定性,并且不同碳氮气体通量的主控因子与耦合关系尚不明确。以长白山温带针阔混交林为研究对象,采用静态箱-气相色谱法连续4a(2005—2009年)测定土壤二氧化碳(CO2)、甲烷(CH4)和氧化亚氮(N2O)净交换通量以及温度、水分等相关环境因子。研究结果表明:温带针阔混交林土壤整体上表现为CO2和N2O的排放源和CH4的吸收汇。土壤CH4、CO2和N2O通量的年均值分别为-1.3 kg CH4hm-2a-1、15102.2 kg CO2hm-2a-1和6.13 kg N2O hm-2a-1。土壤CO2通量呈现明显的季节性规律,主要受土壤温度的影响,水分次之;土壤CH4通量的季节变化不明显,与土壤水分显著正相关;土壤N2O通量季节变化与土壤CO2通量相似,与土壤水分、温度显著正相关。土壤CO2通量和CH4通量不存在任何类型的耦合关系,与N2O通量也不存在耦合关系;土壤CH4和N2O通量之间表现为消长型耦合关系。这项研究显示温带针阔混交林土壤碳氮气体通量主要受环境因子驱动,不同气体通量产生与消耗之间存在复杂的耦合关系,下一步研究需要深入探讨环境变化对其耦合关系的影响以及内在的生物驱动机制。 相似文献
The purpose of this study is to provide a further theoretical basis for the role of Suberoyllanilide hyroxamic acid (SAHA) affect on Dendritic cells (DCs).
Methods
We first downloaded the GSE74306 microarray data, which was about the effect of SAHA act on DCs, from the Gene Expression Omnibus database. Then we analyzed the differential expression genes (DEGs) between SAHA-treated DCs and SAHA-untreated DCs by limma package of R software; The Database for Annotation, Visualization and Integrated Discovery was used to analyze the Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways for these DEGs. The protein protein interaction (PPI) network was constructed by using STRING database, Cytoscape 3.6.1 software was used to dispose the PPI network for visualization. Finally, we determine the Hub genes in the PPI network according by the degree centrality and betweenness centrality, which were calculated by the CentScaPe 2.2 plug-in of Cytoscape 3.6.1 software.
Result
There were 551 DEGs between SAHA-treated DC cells and SAHA-untreated DC cells, including 357 upregulated genes and 194 downregulated genes. These DEGs genes were enriched in 115 Go terms (Biological Process, 51; Cellular Component, 35 and Molecular Function, 29) and a total of 16 pathways. Glutathione metabolic process, Glutathione metabolism pathway, Rheumatoid arthritis pathway and Systemic lupus erythematosus pathway were most significant function clusters. In the PPI network, Rad51, Src, and Eno2 were Hub genes.
Conclusion
The biological function and KEGG pathway enriched by DEGs may reveal the molecular mechanism of SAHA acting on DC cells. Its Hub genes, Src, Rad51 and Eno2, were expected to be new targets for SAHA therapeutic effects. However, it still need to be confirmed by the next more rigorous molecular biological experiments research. 相似文献
【背景】猪链球菌2型(streptococcus suis type 2, SS2)可引起人、猪的脑膜炎、关节炎及败血症等,不仅给养猪业带来巨大的经济损失,同时严重威胁公共卫生安全。本团队前期通过噬菌体展示文库技术发现Orf207编码蛋白可能参与SS2诱导的脑膜炎发生,然而其在SS2致病过程中的具体作用尚不清楚。【目的】探究Orf207基因对SS2致病性的影响。【方法】采用温敏性自杀质粒介导的同源重组系统,构建SC19 Orf207基因缺失菌株ΔOrf207及其回补菌株CΔOrf207,系统比较缺失菌株与野生株间在生长特性、形态、组织定殖能力、毒力情况、细胞黏附与侵袭及抗巨噬细胞吞噬能力等生物学特性方面的差异。【结果】与野生株相比,缺失菌株链长变短,生长速度略慢;而且Orf207缺失显著增加了小鼠的存活率,降低了细菌在血液、心脏、肝脏、脾脏、肺脏、肾脏、脑组织的定殖能力和对肺组织的病理损伤并显著减弱SS2对HeLa细胞的黏附与侵袭能力及抗巨噬细胞吞噬能力。【结论】Orf207基因可以显著降低SS2对宿主的致病能力,本研究结果不仅丰富了SS2的致病机制,也为SS2疫苗等研发提供了新靶点。 相似文献
In this study, the effects of astaxanthin (AST) that belongs to carotenoid family and cadmium (Cd), which is an important heavy metal, on rat erythrocyte G6PD, 6PGD, GR, and TrxR enzyme activities in vivo and on rat erythrocyte 6PGD enzyme activity in vitro were studied. In in vitro studies, 6PGD enzyme was purified from rat erythrocytes with 2′,5′‐ADP Sepharose4B affinity chromatography. Results showed inhibition of enzyme by Cd at IC50; 346.5 μM value and increase of 6PGD enzyme activity by AST. In vivo studies showed an increase in G6PD, 6PGD, and GR enzyme activities (P ? 0.05) and no chance in TrxR enzyme activity by AST. Cd ion inhibited G6PD, 6PGD, and GR enzyme activities (P ? 0.05) and also decreased TrxR enzyme activity (P ? 0.05). AST + Cd group G6PD enzyme activity was statistically low compared with control group (P ? 0.05). 6PGD and TrxR enzyme activities decreased without statistical significance (P ? 0.05); however, GR enzyme activity increased statistically significantly (P ? 0.05). 相似文献
Photoacoustic computed tomography (PACT) is a non‐invasive imaging technique offering high contrast, high resolution, and deep penetration in biological tissues. We report a PACT system equipped with a high frequency linear transducer array for mapping the microvascular network of a whole mouse brain with the skull intact and studying its hemodynamic activities. The linear array was scanned in the coronal plane to collect data from different angles, and full‐view images were synthesized from the limited‐view images in which vessels were only partially revealed. We investigated spontaneous neural activities in the deep brain by monitoring the concentration of hemoglobin in the blood vessels and observed strong interhemispherical correlations between several chosen functional regions, both in the cortical layer and in the deep regions. We also studied neural activities during an epileptic seizure and observed the epileptic wave spreading around the injection site and the wave propagating in the opposite hemisphere.
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