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1.
BackgroundCoronary ischemia can lead to myocardial damage and necrosis. The pathogenesis of cardiovascular diseases often includes increased oxidative stress and decreased antioxidant defense. The study aimed to assess levels of ischemia modified albumin (IMA), malondialdehyde acid (MDA), superoxide dismutase (SOD), and catalase in individuals diagnosed with ST elevated myocardial infarction (STEMI) and non-STEMI.MethodsThe present study prospectively included 50 STEMI patients, 55 NSTEMI patients, and 55 healthy subjects. Only patients who were recently diagnosed with STEMI or NSTEMI were included in this study. IMA, MDA, SOD, and catalase activities were measured spectrophotometrically. Significant coronary artery lesions were determined by angiography.ResultsPatients with ACS had significantly greater IMA and MDA values than the healthy controls (p<0.001). Besides, patients with STEMI had IMA levels that were significantly greater than those of the patients with NSTEMI (p<0.001), while the reverse was true for MDA levels (p<0.001). The healthy controls had the highest levels of SOD and catalase levels, followed by patients with STEMI and patients with NSTEMI, respectively (p<0.001). There was a significant negative correlation among MDA and SOD with catalase levels (r = -0.771 p<0.001 MDA vs catalase; r = -0.821 p<0.001 SOD vs catalase).ConclusionsData obtained in this study reveals that compared to healthy controls, STEMI and NSTEMI patients had increased levels of MDA and IMA and decreased levels of SOD and catalase.  相似文献   
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Effective plant defense strategies rely in part on the perception of non-self determinants, so-called microbe-associated molecular patterns (MAMPs), by transmembrane pattern recognition receptors leading to MAMP-triggered immunity. Plant resistance against necrotrophic pathogens with a broad host range is complex and yet not well understood. Particularly, it is unclear if resistance to necrotrophs involves pattern recognition receptors. Here, we partially purified a novel proteinaceous elicitor called SCLEROTINIA CULTURE FILTRATE ELICITOR1 (SCFE1) from the necrotrophic fungal pathogen Sclerotinia sclerotiorum that induces typical MAMP-triggered immune responses in Arabidopsis thaliana. Analysis of natural genetic variation revealed five Arabidopsis accessions (Mt-0, Lov-1, Lov-5, Br-0, and Sq-1) that are fully insensitive to the SCFE1-containing fraction. We used a forward genetics approach and mapped the locus determining SCFE1 sensitivity to RECEPTOR-LIKE PROTEIN30 (RLP30). We also show that SCFE1-triggered immune responses engage a signaling pathway dependent on the regulatory receptor-like kinases BRASSINOSTEROID INSENSITIVE1-ASSOCIATED RECEPTOR KINASE1 (BAK1) and SUPPRESSOR OF BIR1-1/EVERSHED (SOBIR1/EVR). Mutants of RLP30, BAK1, and SOBIR1 are more susceptible to S. sclerotiorum and the related fungus Botrytis cinerea. The presence of an elicitor in S. sclerotiorum evoking MAMP-triggered immune responses and sensed by RLP30/SOBIR1/BAK1 demonstrates the relevance of MAMP-triggered immunity in resistance to necrotrophic fungi.  相似文献   
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黑果枸杞不同组织内生细菌群落多样性   总被引:3,自引:1,他引:2  
【目的】黑果枸杞是我国荒漠区特有的药用盐生植物,本研究分析了黑果枸杞不同组织中内生细菌群落多样性特征及分布规律。【方法】应用Illumina MiSeq高通量测序技术对黑果枸杞内生细菌的16S rRNAV5-V7区域序列进行测定,并分析群落组成、多样性及功能等生物学信息。【结果】黑果枸杞不同组织内生细菌群落多样性及功能均有较大的差异。花、叶、果、茎和根产生的OTUs分别是182、173、119、187和254,群落多样性表现为根花果、茎叶。从门水平上看,变形菌门是优势菌门,在不同组织中均有分布,花、叶、果、茎和根中的相对丰度分别为87.66%、41.51%、81.76%、97.67%和61.85%。在属水平上显示内生细菌的分布表现出器官差异性。花部能够准确分类的优势菌属为沙雷氏菌属和不动杆菌属,相对丰度分别为11.57%和8.55%。叶部为红球菌属和慢生根瘤菌属,相对丰度分别为29.68%和5.53%。果实中为泛菌属、红球菌属和沙雷氏菌属,相对丰度分别为23.12%、5.52%和4.29%。茎部为沙雷氏菌属和假单胞菌属,相对丰度分别为12.03%和17.71%。根部为盐单胞菌属、Fodinicurvata和Lipingzhangella,相对丰度分别为24.18%、5.16%和4.86%。在不同组织中分布较广的盐单胞菌、沙雷氏菌、不动杆菌、红球菌、泛菌等菌属均具有较高耐盐性和促生、生防、降解有机污染物及抗氧化等功能。PICRUSt功能预测分析显示,黑果枸杞组织中内生细菌功能中涉及丰富的多糖、萜类和酮类、酶及维他命等次生代谢产物的生物合成。【结论】黑果枸杞内生细菌具有丰富的群落和功能多样性,拥有多种益生功能性状,也含有多个与人和植物体代谢相关的功能信息。不同组织优势菌属和功能信息各有不同,其中根部的内生细菌物种最丰富,花部和茎部参与各种代谢调控的细菌丰度最高。此外,不同组织中还含有大量未知种属的微生物类群,这些都为内生细菌功能利用和挖掘新的有益微生物资源提供广阔的发展空间。  相似文献   
5.
The exact role of boron in humans is not known although its supplementation causes several important metabolic and inflammatory changes. The objective of this study is to evaluate the possibility of an association between blood boron level and obesity in normal, overweight, obese, and morbidly obese subjects. A total number of 80 subjects, categorized into four groups based on their body mass index as normal, overweight, obese, and morbidly obese, were enrolled in this study. Age, sex, body mass index, and blood boron levels were recorded for each subject. Although the distribution of female and male subjects and blood boron levels were similar between groups, the mean age of normal subjects was significantly lower than the others (p?=?0.002). There was a significant relationship between age and quantitative values of body mass index for each subject (β?=?0.24; p?=?0.003). In addition, between blood boron levels and quantitative values of body mass index for each subject, a significant reverse relationship was detected (β?=??0.16; p?=?0.043). Although age seemed to be an important variable for blood boron level and body mass index, blood boron levels were shown to be lower in obese subjects in comparison to non-obese subjects.  相似文献   
6.
Low‐resistance contact to lightly doped n‐type crystalline silicon (c‐Si) has long been recognized as technologically challenging due to the pervasive Fermi‐level pinning effect. This has hindered the development of certain devices such as n‐type c‐Si solar cells made with partial rear contacts (PRC) directly to the lowly doped c‐Si wafer. Here, a simple and robust process is demonstrated for achieving mΩ cm2 scale contact resistivities on lightly doped n‐type c‐Si via a lithium fluoride/aluminum contact. The realization of this low‐resistance contact enables the fabrication of a first‐of‐its‐kind high‐efficiency n‐type PRC solar cell. The electron contact of this cell is made to less than 1% of the rear surface area, reducing the impact of contact recombination and optical losses, permitting a power conversion efficiency of greater than 20% in the initial proof‐of‐concept stage. The implementation of the LiFx/Al contact mitigates the need for the costly high‐temperature phosphorus diffusion, typically implemented in such a cell design to nullify the issue of Fermi level pinning at the electron contact. The timing of this demonstration is significant, given the ongoing transition from p‐type to n‐type c‐Si solar cell architectures, together with the increased adoption of advanced PRC device structures within the c‐Si photovoltaic industry.  相似文献   
7.
环境因素在物种进化和遗传变异过程中起着非常重要的作用。为探讨新疆鹅喉羚遗传多样性与环境因子的关系,本研究采用聚合酶链式反应(PCR)和直接测序的方法,测定了新疆鹅喉羚11个群体84份样本的线粒体DNA Cyt b基因(1140 bp)和D-loop区(1100 bp)序列,分析各群体遗传多样性及环境因子对遗传多样性的影响。结果显示新疆鹅喉羚具有较高的单倍型多样性,较低的核苷酸多样性,表明其遗传多样性处于较低水平。环境因子与群体遗传多样性的相关性分析结果表明,海拔、年均降水量、年均气温、人口数量是影响新疆鹅喉羚遗传多样性的主要环境因子,其中海拔是最关键的环境因子。本研究结论为新疆鹅喉羚群体有效合理的保护与管理提供理论依据。  相似文献   
8.
Yu  Zhiming  Wang  Yue  Mei  Fengling  Yan  Haiting  Jin  Zhenhui  Zhang  Pengcheng  Zhang  Xian  T&#;r  Mahmut  Jackson  Stephen  Shi  Nongnong  Hong  Yiguo 《Functional & integrative genomics》2022,22(3):423-428
Functional & Integrative Genomics - Spinach RNA-mimicking GFP (S-RMG) has been successfully used to monitor cellular RNAs including microRNAs in bacterium, yeast, and human cells. However,...  相似文献   
9.
探究了新疆盐生植物黑果枸杞不同组织中内生真菌群落的组成及多样性,为深入研究盐碱、干旱等环境下内生真菌与宿主的互作机制,筛选和开发促生、防病和抗逆等功能的有益内生真菌资源提供科学依据。利用ITS高通量测序技术比较黑果枸杞不同组织真菌群落组成及差异,并采用FUNGuild数据库预测真菌群落生态功能。测序共获得高质量内生真菌序列354 058条,涉及291个OTUs,分属于9门、19纲、34目、50科、60属。α多样性指数分析表明,根、果中真菌群落多样性和丰富度程度较高,叶居中,花的多样性最低,茎的丰富度最低。对黑果枸杞内生真菌群落组成和优势菌群的分析表明,子囊菌门为优势菌门,花、叶、果、茎和根中相对丰度分别为86.85%、72.36%、75.97%、84.44%和85.02%。链格孢属为黑果枸杞植株中的核心属,不同组织中均有分布,在花、叶、果、茎和根中占比分别为85.41%、69.79%、47.07%、79.94%和36.97%。较优势的菌尚有枝孢属、枝顶孢属、新凸轮孢菌属、茎点霉属和楔孢黑粉菌属等真菌。这些菌多具有促生、抗逆等特性,在宿主对盐碱、干旱等极端环境的适应性方面有着潜在功能。各组织独有属的相对丰度均未超过1%。共有菌和独有菌在不同组织中的组成和相对丰度差异较大。经FUNGuild软件平台解析显示,黑果枸杞中病理-腐生-共生营养型的相对丰度最高,在花、叶、果、茎和根中分别为85.41%、69.84%、47.24%、79.98%和37.09%。果和叶中含多种相对丰度≥1%的条件致病菌,而根中腐生真菌种类较多。黑果枸杞中蕴含着功能丰富的内生真菌菌群,在不同组织中的组成及其生态功能差异较大,同时还含有大量未鉴定出种属和未定义的功能菌群,这些可为黑果枸杞功能菌群发掘提供数据参考。  相似文献   
10.
Resistance responses that plants deploy in defence against pathogens are often triggered following a recognition event mediated by resistance (R) genes. The encoded R proteins usually contain a nucleotide-binding site (NB) and a leucine-rich repeat (LRR) domain. They are further classified into those that contain an N-terminal coiled coil (CC) motif or a Toll interleukin receptor (TIR) domain. Such R genes, when transferred into a susceptible plant of the same or closely related species, usually impart full resistance capability. We have used map-based cloning and mutation analysis to study the recognition of Peronospora parasitica (RPP)2 (At) locus in Arabidopsis accession Columbia (Col-0), which is a determinant of specific recognition of P. parasitica (At) isolate Cala2. Genetic mapping located RPP2 to a 200-kb interval on chromosome 4, which contained four adjacent TIR:NB:LRR genes. Mutational analysis revealed three classes of genes involved in specifying resistance to Cala2. One class, which resulted in pleiotropic effects on resistance to other P. parasitica (At) isolates, was unlinked to the RPP2 locus; this class included AtSGT1b. The other two classes were mapped within the interval and were specific to Cala2 resistance. Representatives of each of these classes were sequenced, and mutations were found in one or the other of two (RPP2A and RPP2B) of the four TIR:NB:LRR genes. RPP2A and RPP2B complemented their specific mutations, but failed to impart resistance when present alone, and it is concluded that both genes are essential determinants for isolate-specific recognition of Cala2. RPP2A has an unusual structure with a short LRR domain at the C-terminus, preceded by two potential but incomplete TIR:NB domains. In addition, the RPP2A LRR domain lacks conserved motifs found in all but three other TIR:NB:LRR class proteins. In contrast, RPP2B has a complete TIR:NB:LRR structure. It is concluded that RPP2A and RPP2B cooperate to specify Cala2 resistance by providing recognition or signalling functions lacked by either partner protein.  相似文献   
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