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1.
目的了解抗生素对肺炎婴幼儿肠道菌群多样性和结构的影响。方法选取5例1岁以内因轻度社区获得性肺炎住院的患儿,收集抗生素治疗前及治疗后第3~5天的粪便标本。利用Illumina MiSeq测序平台,对细菌的16SrRNA基因V3~V4区进行高通量测序,并对测序结果进行生物信息学分析。结果抗生素治疗后第3~5天婴幼儿肠道菌群的多样性明显下降。变形菌门的相对丰度在3例婴幼儿的肠道中下降;厚壁菌门的相对丰度在4例婴幼儿的肠道中下降;而拟杆菌门的相对丰度在4例婴幼儿的肠道中上升;厚壁菌门与拟杆菌门的比例下降。肠道内不动杆菌属、喜胆汁菌属、埃格特菌属、肠球菌属、支原体、颤螺菌属、紫单胞菌属、普雷沃菌属和真杆菌属增长1倍以上;奇异菌属、双歧杆菌属、黄杆菌属、乳酸菌属、链球菌属、萨特菌属和韦荣球菌下降超过50%。结论婴幼儿短期使用抗生素治疗肺炎后,肠道菌群的多样性下降,肠道微生态失衡。  相似文献   

2.
目的探究中部和西部地区幼儿肠道菌群的结构差异与膳食的关系,为幼儿营养健康状况监测和营养改善工作提供有效的营养干预。方法选择“贫困地区儿童营养改善项目”河南汝阳和贵州福泉,随机抽取107名汉族健康幼儿为调查对象,食物摄入采用24 h消费调查方法。应用高通量测序技术对肠道菌群进行测序和生物信息分析,研究两县幼儿肠道菌群差异。结果两县幼儿肠道菌群组成结构较为一致,但Alpha多样性分析表明,贵州福泉县幼儿肠道物种丰富度和多样性高于河南汝阳县。细菌属水平分析中,两县幼儿肠道内均以拟杆菌属、普雷沃菌、柔嫩梭菌和双歧杆菌属为主导的菌群结构,但河南汝阳县幼儿肠道双歧杆菌属和乳杆菌属丰度显著高于贵州福泉县(12.36% vs. 7.44%;0.19% vs. 0.03%)。结论中西部地区幼儿肠道菌群结构差异不大,但有益菌含量存在显著差异,这为研究肠道菌群与膳食及营养健康状况之间的关系提供了依据。  相似文献   

3.
目的为了解湿疹患儿肠道菌群的结构与湿疹之间的关系,通过对湿疹患儿和健康儿童粪便样本细菌总DNA提取,利用高通量测序技术,比较健康儿童和湿疹患儿肠道菌群的异同。方法 10例年龄在2个月~2岁婴幼儿由皮肤科门诊确诊为湿疹伴有过敏性疾病家族史作为研究对象,年龄和性别相当健康儿童10例作为对照,分别收集其粪便标本并提取所有样本中细菌的总DNA,对16SrRNA基因进行高通量测序,获得两组的肠道菌群结构数据并进行菌群差异性分析。结果通过Roche 454高通量测序,两组肠道微生物菌群多样性指数比较差异无统计学意义。两组主要由Firmicutes(厚壁菌门)、Bacteroidetes(拟杆菌门)、Proteobacteria(变形菌门)和Actinobacteria(放线菌门)4个门组成;两组在门水平上进行菌群结构比较,差异无统计学意义。两组样本在属水平上共获得200个不同属的细菌,其中Bacillus(芽孢杆菌属)、Bilophila(噬胆菌属)、Christensenella(纺锤状细菌属)、Coprobacillus、Eikenella(艾肯菌属)、Enterobacter(肠杆菌属)、Eubacterium(真杆菌属)、Lactococcus(乳球菌属)、Megamonas(巨单胞菌属)、Leuconostoc(明串珠菌属)、Morganella(摩根菌属)、Rhizobacter(根杆菌属)、Proteus(变形菌属)、Sutterella(萨特菌属)、Veillonella(韦荣球菌属)、Akkermansia、Anaeroglobus、Anaerotruncus、Butyricicoccus、Epulopiscium、Gordonibacter、Lachnospiraceae uncultured、Robinsoniella和Varibaculum共24个属在两组间差异具有统计学意义。结论湿疹患儿肠道菌群与健康儿童相比,菌群多样性指数(Shannon指数和Simpson指数)未见明显差异,但在菌群结构上发生了一些变化,某些特别的细菌菌属存在显著性差异。  相似文献   

4.
目的研究克罗恩病(Crohn′s disease, CD)儿童和正常人群肠道菌群的分布,寻找与CD发生发展显著相关的菌属结构。方法纳入CD患儿36例和健康儿童21例,CD患儿分为活动期22例、缓解期14例,采用16S rDNA高通量测序技术,分析各组肠道菌群的生物多样性与结构组成。结果 CD组患儿(活动期与缓解期)肠道菌群丰富度指数、香浓多样性指数较健康儿童组有明显下降,差异有统计学意义(F=8.829 0,P=0.001 0,P=0.004 5;F=8.890 0,P=0.000 3,P=0.035 6)。在门类水平,所有CD患儿肠道菌群的放线菌门数量减少,变形菌门数量增多。在菌属水平,与健康儿童组相比,所有CD组患儿Faecalibacterium相对丰度显著减低,Klebsiella(克雷伯菌属)、Enterococcus(肠球菌属)相对丰度显著升高。活动期CD组Blautia(布劳特菌属)、Bifidobacterium(双歧杆菌属)、Subdoligranulum、Lachnospira(毛螺旋菌属)、Anaerostipes(丁酸弧菌属)、Eubacterium_rectale_group(直肠杆菌属)的相对丰度明显下降。结论 CD患儿肠道菌群结构及相对丰度较健康儿童存在显著差异。肠道菌群结构的异常与儿童CD的发生发展存在相关性。  相似文献   

5.
摘要:目的 通过比较健康婴幼儿与百日咳鲍特菌感染婴幼儿口咽部的菌群相对丰度,探讨百日咳鲍特菌感染对婴幼儿口咽部的菌群影响。方法 采用高通量测序技术,对53例百日咳鲍特菌感染婴幼儿和21例健康婴幼儿口咽标本进行16S rDNA测序,对测序序列进行分析,比较两组间的菌群多样性及在门、属水平上菌群结构差异。结果 健康婴幼儿与百日咳鲍特菌感染患儿在性别和年龄方面差异没有统计学意义。百日咳鲍特菌感染婴幼儿比健康婴幼儿口咽部菌群多样性显著增加。变形菌门(Proteobacteria)作为主要的门在百日咳鲍特菌感染患儿组中相对丰度显著高于健康婴幼儿组;两组排在相对丰度前15位的属,共有3个主要的属在百日咳鲍特菌感染患儿中显著增加,分别为盐单胞菌属(Halomonas)、嗜血杆菌属(Haemophilus)和鲍特菌属(Bordetella);而罗氏菌属(Rothia)显著减少。结论 百日咳鲍特菌感染婴幼儿口咽部的菌群发生了显著的变化,百日咳鲍特菌感染患儿口咽部的菌群多样性比健康婴幼儿显著增加,在门和属水平百日咳鲍特菌感染患儿与健康婴幼儿主要组成方面均有显著性不同。  相似文献   

6.
目的通过比较甘肃省武威市胃癌患者和健康对照人群肠道菌群的分布,探讨胃癌患者肠道菌群的变化与胃癌发生发展的关系,并寻找可能作为该地区胃癌患者的潜在生物标志物。方法收集24例胃癌患者和24例健康对照人群的粪便样本,提取DNA,采用16S rRNA基因高通量测序进行肠道菌群分析。结果分析2组研究对象肠道菌群的Alpha多样性,发现胃癌患者组和健康对照组肠道菌群的Chao1指数差异无统计学意义(Z=-0.907,P=0.364),胃癌患者组的Simpson指数升高且差异具有统计学意义(Z=-3.258,P=0.001),表明武威市胃癌患者肠道菌群多样性增加;物种差异分析表明,2组人群在门水平上,Fusobacteria、Patescibacteria、Synergistetes的相对丰度变化差异具有统计学意义(均P0.05),在属水平上,Bacteroides(拟杆菌属)、Lachnospiraceae_UCG-008、Lachnoclostridium、Blautia、Roseburia等34个菌属的相对丰度变化差异具有统计学意义(均P0.05)。通过菌属微生物关联网络图发现,在34个差异菌属中,Streptococcus、Erysipelotrichaceae_UCG-003等菌属的节性重要性较高;通过LEfSe分析和组间秩和检验分析发现,Lac_Lachnospira、Lachnospiraceae_UCG-004在健康对照组和胃癌患者组之间是显著差异的菌属。结论与健康对照组人群的肠道菌群比较,胃癌患者组的菌群多样性增加,胃癌患者肠道菌群的改变主要以Lachnospiraceae等益生菌属的相对丰度减少和Alloprevotella、Desulfovibrio等致病菌属的相对丰度增加为主。Lac_Lachnospira、Lachnospiraceae_UCG-004可能为武威市胃癌患者潜在生物标志物。  相似文献   

7.
大熊猫肠道放线菌的种群组成及多样性分析   总被引:1,自引:0,他引:1  
【目的】探究不同年龄、不同性别大熊猫肠道放线菌的多样性及群落结构,为寻找潜在产生活性化合物的放线菌资源提供理论依据。【方法】采用PCR-DGGE技术对大熊猫肠道放线菌进行分析,对电泳结果进行UPGMA聚类分析、主成分分析、生物多样性等多重比较。【结果】变性梯度凝胶电泳(DGGE)图谱显示,不同大熊猫肠道中放线菌的多样性及群落结构存在明显差异。随着年龄的增长,雌性大熊猫肠道中放线菌的多样性指数(H')和丰富度(S)逐渐减少,而雄性大熊猫肠道内放线菌的多样性指数(H')和丰富度(S)逐渐增多。不同个体的大熊猫肠道放线菌的群落结构存在明显差异,但相同性别之间的相似性很高。DGGE条带回收测序结果表明,获得的28条序列归属于10个放线菌属,其中链霉菌属(Streptomyces)为优势菌属,占总数的46%;北里孢菌属(Kitasatospora)、红球菌属(Rhodococcus)、棒杆菌属(Corynebacterium)、迪茨氏菌属(Dietziaceae)、大理石雕菌属(Marmoricola)、布登堡菌属(Beutenbergia)、微杆菌属(Microbacterium)、链嗜酸菌属(Streptacidiphilus)和芽生球菌属(Blastococcus)等为非链霉菌属,占总数的54%。【结论】大熊猫肠道内蕴藏着丰富的放线菌资源,其肠道菌群的结构与组成受年龄和性别的影响。  相似文献   

8.
目的探索不同人群在不同年龄阶段的菌群结构特点,了解环境因素对肠道菌群组成及发展的影响。方法收集65例中国健康儿童粪便样本并进行16S rRNA检测,同时从已发表文献中获取来自亚洲、非洲、欧洲、北美洲及南美洲国家的1 002例健康人群肠道菌群数据,分析来自不同年龄阶段健康人群肠道菌群的特征。结果 3岁以下全球各地儿童肠道菌群的种类较为一致:拟杆菌属和双歧杆菌属在儿童肠道菌群中占据主导地位,且它们在免疫调节上有重要作用。3岁以上健康人群的肠道菌群则展示出了地域性特征:亚洲健康人群的肠道代表菌属为考拉杆菌属和巨单胞菌属,非洲健康人群的肠道代表菌属为粪杆菌属,欧洲健康人群的肠道代表菌属也是粪杆菌属,北美洲健康人群的肠道代表菌属为拟杆菌属,南美洲健康人群的肠道代表菌属为普氏菌属。另外,经济较发达的欧洲及北美洲健康人群的肠道菌群多样性显著高于其他经济较落后地区。结论本研究加深了对不同地域人群肠道菌群特点以及它们随年龄增长而发展变化的认识。  相似文献   

9.
目的对青海省天峻县的藏族牧民健康志愿者肠道菌群进行研究,探讨青海藏民肠道菌群结构及性别对肠道菌群组成的影响。方法以28例藏族牧民志愿者的粪便样品作为研究对象,应用基于16SrDNA V3+V4可变区的高通量测序技术测定肠道菌群组成及核心菌群;通过db-RDA和菌群多样性分析,探索性别因素对肠道菌群结构的影响。结果在门水平上,厚壁菌门和拟杆菌门是青海藏族志愿者的优势菌群。在属水平上,优势菌属是普氏菌属、Lachnospiracea_incertae_sedis、Faecalibacterium和拟杆菌属;特有优势菌属是Lachnospiracea_incertae_sedis。db-RDA结果显示性别因素对肠道微生物群结构有一定分离趋势,多样性结果进一步证实性别差异显著影响菌群结构。男性和女性存在12种差异菌群,包括普氏菌属、Acidaminobacter属等。结论性别差异对青海藏民肠道菌群影响显著。  相似文献   

10.
目的 探究乳腺癌患者抑郁症状与肠道微生物的相关性。方法 选取辽宁省肿瘤医院2018年1月至2019年1月诊断及治疗的乳腺癌伴抑郁患者28例,作为抑郁组,同时选取无抑郁的乳腺癌患者28例作为对照组。对两组患者进行肠道微生物检测,使用Pearson模型探究患者肠道微生态特征与抑郁水平的相关性。结果 两组肠道菌群的组成存在一定差异,两组拟杆菌目、肠杆菌科、普氏菌属、克雷伯菌属、链球菌属、埃格特菌属、乳杆菌属、拟杆菌属、帕拉拟杆菌属、瘤胃球菌属的丰度具有差异(P0.05),两组样本菌群多样性具有差异。Pearson相关性分析显示,乳杆菌属与抑郁自评量表(BDI)评分呈显著负相关(r=-0.792,P0.001);拟杆菌目、克雷伯菌属与BDI评分呈显著正相关(r=0.458,0.477,P=0.003,0.002)。结论 乳腺癌患者抑郁症状与肠道菌群中的拟杆菌目、乳杆菌属、克雷伯菌属具有相关性。  相似文献   

11.
The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects.  相似文献   

12.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

13.
The cell has been represented as a charged liquid drop. Contrary to the DLVO-theory, the effect of the surface potential upon the value of the interfacial tension of the cell membrane has also been taken into consideration. The cell membrane has visco-elastic properties and its constituents may move against each other. Cell movement is caused by the appearance of a small number of the electrically charged constituents of the cell membrane on the leading edge of the cell. This produces a local decrease in the surface tension and the cell membrane expansion. At the moment of contact between two cells proton transfers occur between the strongly negatively charged microvilli of one cell and the body of the other, analogous to a condenser breakdown. This, through the effect on the surface tension, causes contact inhibition of movement. The distribution of the proton dissociable groups modifies the interaction between the cells (differentiation) and between the cell and the substratum (adhesion). Adsorption of the charged compounds at the surface of the cell membrane, decreasing the surface potential and increasing the surface tension, causes the phenomena of chemotaxis, phagocytosis and pinocytosis. Cell division, considered in the terms of the surface energy, requires an adequate supply of considerable quantities of energy inversely proportional to the surface potential value. In case of a reduction of the distance between the cells, their surface potential and the energetic barrier of the cell division processes increases, and causes contact inhibition of cell division. Due to their high charge, division of neoplastic cells is inhibited much later than division of normal cells, or is completely ininhibited due to geometric conditions. Fusion of the cell membrane in the intra-cellular and intercellular processes is a reverse process in relation to the cell division.  相似文献   

14.
15.
Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive to diazinon. Long-term exposure to pesticides modified morphology and behavior. The LC50-96 values for Cu, Hg, and Pb were 0.3, 0.16, and 0.44, respectively, for smaller fish and 1.0, 0.77, and 1.33, respectively, for larger fish. Replicate LC50 values for Zn, Ni, and Fe were somewhat variable, and for these metals, the size of the fish seemed to affect response because LC50 values increased as fish size increased. Cooper, Pb, Zn, and Fe residues following exposure to sublethal concentrations of these metals for 15 d were significantly greater in whole juvenile common carp than in controls.  相似文献   

16.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

17.
The sieve-element plastids of 69 species of theCaryophyllales were investigated by transmission electron microscopy. All contained the specific subtype-P3 plastids characterized by a peripheral ring of protein filaments. The presence or absence of an additional central protein crystal and their shape being either polygonal or globular as well as the average sizes of the sieve-element plastids are useful features in the characterization of some families.—Barbeuia contains sieve-element plastids that confirm its placement within thePhytolaccaceae. Lyallia differs fromHectorella by including small starch grains in their sieve-element plastids, which otherwise by their globular crystals negate a closer connection to theCaryophyllaceae. The lack of a central protein crystal in its form-P3fs plastids placesMicrotea best within theChenopodiaceae. Sarcobatus, a so far uncontested member of theChenopodiaceae, contains form-P3cf plastids, i.e., including a central crystal not found elsewhere in this family.Telephium andCorrigiola, shifted back and forth betweenMolluginaceae andCaryophyllaceae, have form-P3cf(s) plastids with a polygonal crystal which favor their placement within theCaryophyllaceae.  相似文献   

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The translocation of the radionuclides of Co, Zn, Se, Rb, Y, Tc, and Re into red and green fruits, flesh, seeds, rind, calyxes, flower, leaves, and stems via the root of the tomato plant at two different growth stages was studied by a multitracer technique. The contents (%/g) of Co, Zn, Se, and Y in the roots were the highest among the organs, but only small amounts of them were translocated into the aerial parts after 5 d cultivation with a multitracer. In contrast, Rb, Tc, and Re showed rapid translocation into the stems and leaves from the root. In the plants cultivated for 95 d with a multitracer, Zn, Se, and Rb distributed in all of the organs, Co in the organs except for flowers, and Y, Tc, and Re in the limited organs. The translocation ratio of the elements for the edible part of the plants cultivated for 95 d decreased in the order of Rb>Zn>Co≈Se>Tc≈Y>Re. The transfer factor of the elements for tomato fruit was determined to be in the range of 10−5–10−2. The characteristic translocation behavior of the elements gives us fundamental information on the assessment of pollutant uptake by the tomato plant.  相似文献   

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