小儿腹泻与肠道细菌群落多样性的关系

摘要腹泻是婴幼儿常见疾病，小儿腹泻的原因多种多样，而腹泻可能会使肠道微生物发生变化。本文采集了 7位腹泻小儿和 4位正常小儿的粪便样本，由上海美吉生物医药科技有限公司对小儿粪便中细菌的 16S rDNA 使用Illumina 的 Miseq平台进行高通量测序，并使用生物信息学软件分析不同样本中细菌群落的多样性，旨在找到由不同原因导致的腹泻与肠道菌群之间的关系。结果通过测序得到317657 个 reads，148 个 OTU，根据样品化验单结果将其分为白细胞增加组(Leukocytosis) (S5, S6, S8, S10)、消化不良组(Dyspepsia) (S1, S2, S7)和正常组(Normal) (Z1, Z4, Z7, Z10)。白细胞增加组的病因大多是细菌感染性腹泻，在该组中也发现了大量的埃希氏-志贺氏菌属(Escherichia-Shigella)、假单胞菌(Pseudomonas)等致病菌。S6的物种多样性最高，且拟杆菌门的物种种类比其他的样品要丰富。S8和 Z4 虽然表征不同，但是它们在聚类树中距离相近，表示多样性相似。在消化不良组中，放线菌门的细菌较多，S2 和 S7 距离相近，S1 与S2和 S7的距离较远，在 S1中发现了 36.6%的克雷伯氏菌属(Klebsiella), S1的粪检报告中乳糖呈阳性，可能由于 S1出现乳糖不耐受，克雷伯氏菌可以分解乳糖产生乳酸和CO2，引发腹泻。正常组样品中 Z7 和Z10 距离相近，且含有较高的厚壁菌门的肠球菌属(Enterococcus)，有助于维持肠道功能正常运转和调节菌群平衡。该论文有图8 幅，表1 个，参考文献44 篇。51079
毕业论文关键词：小儿腹泻细菌多样性肠道菌群高通量测序
The Relationship between Different Reasons CausingDiarrhea and Intestinal Bacterial Diversity
Abstract Diarrhea is a common disease of children. There are many reasons for causingchildren diarrhea and they can change their gut microbe. In this study, we collectedstool samples from 7 diarrhea children and 4 normal children. The stool samples weresent to Majorbio Bio-pharm Technology Co., Ltd., Shanghai, China for sequencing. Itused Illumina Miseq high through-put technology to sequence 16S rDNA extractedfrom the samples. Sequences were analyzed by bioinformatics software to comparemicrobial persity of each sample. The aim of this study is to find out therelationships between the different reasons causing diarrhea and intestinal flora. Theresult showed 317657 reads and 148 OTU according to the sequence. We pidedsamples into three groups based on their characteristics: Leukocytosis (S5, S6, S8,S10), Dyspepsia (S1, S2, S7) and Normal (Z1, Z4, Z7, Z10). Leukocytosis wasmainly caused by bacterial infection. We discovered some pathogenic bacteriaincluding Escherichia-Shigella and Pseudomonas from this group. S6 had the mostabundant microbial persity and its species of Bacteroidetes were richer than othersamples. Although having different characteristics, S8 and Z4 stayed close inclustering tree, which meant they had same persity. Actinobacteria was the mostabundant phylum in Dyspepsia. S2 and S7 were close to each other, but S1 was faraway from them. We found 36.6% Klebsiella in S1 and lactose test was positive inS1’s fecal inspection report. It may because S1 has lactose-intolerance and Klebsiellacan decompose lactose to produce lactic acid and CO2, which leading to diarrhea. Z7and Z10 both had large proportion of Enterococcus that it can keep the normalfunction of children’s gut and adjust the balance of intestinal microflora.
KeyWords: children diarrhea microbial persity intestinal microflora highthrough-put sequencing

摘要Ⅰ

Abstract-Ⅱ

目录Ⅲ

图清单-Ⅳ

表清单-Ⅳ

1 绪论1

2 材料与方法-2

2.1 实验材料2

2.2 粪便 DNA 的提取和 PCR 扩增2

2.3 16S rDNA 测序和生物信息学分析2

3 结果与分析-3

3.1 儿童基本信息3

小儿腹泻与肠道细菌群落多样性的关系:http://www.751com.cn/yixue/lunwen_54591.html