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21.
The development and progression of gastric cancer (GC) is greatly influenced by gastric microbiota and their metabolites. Here, we characterized the gastric microbiome and metabolome profiles of 37 GC tumor tissues and matched non-tumor tissues using 16s rRNA gene sequencing and ultrahigh performance liquid chromatography tandem mass spectrometry, respectively. Microbial diversity and richness were higher in GC tumor tissues than in non-tumor tissues. The abundance of Helicobacter was increased in non-tumor tissues, while the abundance of Lactobacillus, Streptococcus, Bacteroides, Prevotella, and 6 additional genera was increased in the tumor tissues. The untargeted metabolome analysis revealed 150 discriminative metabolites, among which the relative abundance of the amino acids, carbohydrates and carbohydrate conjugates, glycerophospholipids, and nucleosides was higher in tumor tissues compared to non-tumor tissues. The targeted metabolome analysis further demonstrated that the combination of 1-methylnicotinamide and N-acetyl-D-glucosamine-6-phosphate could serve as a robust biomarker for distinction between GC tumors and non-tumor tissues. Correlation analysis revealed that Helicobacter and Lactobacillus were negatively and positively correlated with the majority of differential metabolites in the classes of amino acids, carbohydrates, nucleosides, nucleotides, and glycerophospholipids, respectively, suggesting that Helicobacter and Lactobacillus might play a role in degradation and synthesis of the majority of differential metabolites in these classes, respectively. Acinetobacter, Comamonas, Faecalibacterium, Sphingomonas, and Streptococcus were also significantly correlated with many differential amino acids, carbohydrates, nucleosides, nucleotides, and glycerophospholipids. In conclusion, the differences in metabolome profiles between GC tumor and matched non-tumor tissues may be partly due to the collective activities of Helicobacter, Lactobacillus, and other bacteria, which eventually affects GC carcinogenesis and progression.Subject terms: Cancer metabolism, Gastrointestinal cancer  相似文献   
22.
A new 3,3'-biflavanone, isosikokianin A, was isolated from the roots of Stellera chamaejasme, together with eleven known compounds. Their structures and configurations were elucidated by spectroscopic methods including 2D-NMR techniques. Sikokianin A, chamaechromone, and quercetin showed in vitro antiviral activity against HBsAg secretion.  相似文献   
23.
保安湖沉水植物分布的GIS模拟   总被引:9,自引:1,他引:9  
马凯  蔡庆华  谢志才  黎道丰  叶麟 《生态学报》2003,23(11):2271-2277
以GPS为辅助,在保安湖主体湖和桥墩湖进行沉水植物调查。将野外调查数据构建GIS数据库,基于GIS软件平台,运用Kringing插值法对保安湖沉水植物分布进行模拟。模拟结果清楚地显示出调查时保安湖沉水植物及4优势种(金鱼藻Ceratophyllum demersum L.、穗状狐尾藻Myriophyllum spicatum L.、微齿眼子菜Potamogeton maackianus A.Benn.及苦草Vallisneria spiralis L.)分别在湖中的分布情况。统计后结果表明沉水植物覆盖面积占全湖面积的92.9%,总生物量(湿重)为143682.4t。比较历史数据,发现湖中水生植被组成特征已由微齿眼子菜绝对优势转变为4种植物的共同优势。  相似文献   
24.
25.
Zhang  Ai Hua  Feng  Bo  Zhang  Han  Jiang  Jinshun  Zhang  Daofeng  Du  Yi  Cheng  Zheng  Huang  Jianke 《Journal of applied phycology》2022,34(5):2315-2326
Journal of Applied Phycology - In the present study swine wastewater diluted at the different percentages (10%, 20%, 60%, and 100%) was used to cultivate the red alga Porphyridium purpureum to...  相似文献   
26.
The HC-pro protein of potato virus Y interacts with NtMinD of tobacco   总被引:1,自引:0,他引:1  
Potato virus Y (PVY) infections often lead to altered numbers of host plant chloroplasts, as well as changes in morphology and inhibited photosynthesis. The multifunctional protein helper component-proteinase, HC-Pro, has been identified in PVY-infected leaf chloroplasts. We used yeast two-hybrid and bimolecular fluorescence complementation assays to demonstrate that HC-Pro can interact with the chloroplast division-related factor NtMinD in yeast and tobacco cells, respectively. In addition, we confirmed that residues 271 to 314 in NtMinD are necessary for its interaction with PVY HC-Pro in a yeast two-hybrid analysis using four NtMinD deletion mutants. These residues are necessary for the dimerization of NtMinD, which plays a vital role in chloroplast division. Thus, PVY HC-Pro may affect NtMinD activity by inhibiting the formation of NtMinD homodimers, and this may interfere with chloroplast division and contribute to changes in the numbers of chloroplast per cell observed in PVY-infected plants.  相似文献   
27.
湖泊岸线分形特征及其生态学意义   总被引:13,自引:1,他引:13  
潘文斌  黎道丰  唐涛  蔡庆华 《生态学报》2003,23(12):2728-2735
应用分形理论中的计盒维数、岸线长度与面积关系对保安湖及江汉平原一些湖泊的湖岸线长度和湖泊面积进行研究.借以对上述两个物理性质进行准确的特征化。此外还运用Korcak法则对湖北省湖泊面积分布进行研究。结果可用于预测湖泊岸线长度如何随着湖泊面积而变化.以及预测不同大小的湖泊面积分布。探讨了湖岸形态和大型水生植物生物量间的关系,并讨论环境和人为因素对湖泊岸线的影响.以及湖泊岸线变化对湖泊生物的影响。  相似文献   
28.
As a key enzyme in the biosynthesis of flavonols, anthocyanidins and proanthocyanidins, flavanone-3ß-hydroxylase (F3H) plays very important roles in plant stress response. A putative flavanone-3ß-hydroxylase gene from Medicago truncatula (MtF3H), a model legume species, was identified from a bio-data analysis platform. It was speculated to be induced by salt stress based on the outcomes of the analysis platform. The complementary DNA (cDNA) consists of 1499 bp with an open reading frame (ORF) of 1098 bp, which encodes a putative protein of 365 amino acids with a molecular weight of about 41.36 kDa and an isoelectric point of 5.60. To measure the catalytic activity of the protein, the MtF3H gene was ligated to pYES2 vector and heterologously expressed in yeast. The recombinant protein converted naringen into dihydrokaempferol and displayed different enzymatic efficiencies with other flavanones, confirming that MtF3H coding a functional flavanone-3ß-hydroxylase. The expression pattern of the MtF3H gene was analyzed by comparative quantitative RT-PCR and a higher level of expression was observed in the roots than was observed in stems and leaves. Furthermore, the expression was induced by salt stress in the roots, and to a greater extent in the stems, but the response of the gene activity to salt stress in the stems was slower in the first 12 h following treatment when compared to the roots.  相似文献   
29.
银白色葡萄球菌(Staphylococcus argenteus)是金黄色葡萄球菌(S. aureus)的近缘新种,于2015年正式被鉴定、命名。在此之前,银白色葡萄球菌一直被认为是金黄色葡萄球菌种内的一个远源支系。该物种绝大多数菌株分离自人体,基因组上含有大量与金黄色葡萄球菌同源的毒力基因,可导致与金黄色葡萄球菌类似的临床感染和食物中毒症状。因为与人类健康相关,银白色葡萄球菌受到了越来越多的关注,目前已在20多个国家被报道。但是由于出现较晚,与金黄色葡萄球菌难以区分,银白色葡萄球菌的全球分布状况、原始生境和传播过程尚不清楚。本文从发现过程、分布、致病性和鉴定方法等方面综述了银白色葡萄球菌的最新研究进展。  相似文献   
30.
自1936年细菌学家Buchanan负责起草专门的细菌命名法规以来,国际原核生物命名法规(International Code of Nomenclature of Prokaryotes, ICNP)在不断发展和完善过程中,积极促进了原核生物分类学及相关学科的发展。随着组学技术在原核生物多样性研究中的应用,越来越多未培养的细菌和古菌新类群被发现,却因为ICNP要求活的生物材料作为命名模式(nomenclatural type),而无法获得生效名称(validly published name)。2022年,原核生物命名法规从序列数据描述原核生物命名法(Code of Nomenclature of Prokaryotes Described from Sequence Data, SeqCode)正式发布,以补充ICNP在未培养微生物类群命名方面的不足。SeqCode不希望和ICNP产生较大分歧,并尽可能保留在将来和ICNP合并的可能性。然而,作为两种独立运行的命名法规,尚不明确SeqCode和ICNP并存会对学术界产生怎样的影响。本文系统介绍了ICNP和SeqCode各自的发展历程和主要内容,分析了二者的优势和局限性,并呼吁微生物学相关领域的学者共同关注原核生物命名法规并应用于实践,以期构建更加合理、有效的原核生物名称系统。  相似文献   
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