Table_2_Necrotizing Enterocolitis and Intestinal Microbiota: The Timing of Disease and Combined Effects of Multiple Species.XLS

Background: The purpose of this study was to investigate the relationship between intestinal microbiota and necrotizing enterocolitis (NEC).Methods: 16S rRNA gene sequencing was used to compare the microbial composition of feces. The first sample was collected within 48 h after birth, then once per week until the NEC diagnosis, and finally 1–2 weeks after treatment or 28 days after birth.Results: The alpha diversity of the microbiota in the NEC group was higher than that in the control group. Beta diversity analysis showed that the control group had a higher similarity at the onset of NEC, while the NEC group was distributed in subgroups. Linear discriminant analysis effect size and taxonomic composition analyses indicated that the abundance of Bacteroides and Actinobacteria in NEC infants at birth was much higher than that in the control group, and this trend continued until NEC occurred. At this time, Rhizobiales, Dysgonomonas, Ochrobactrum, Ralstonia, Pelomonas, Acinetobacter, etc., were also more abundant in NEC infants. The upregulated different metabolic pathways in the NEC group were mainly concentrated on degradation/utilization/assimilation, biosynthesis, and generation of precursor metabolites and energy.Conclusions:1. The microbial community differs according to the time of NEC diagnosis (bounded by 20 days).2. No single microorganism is related to NEC, and the combined effect of multiple species is of great significance in the occurrence of NEC. Premature infants are easily affected by bacteria living in the environment, and compared with ordinary premature infants, NEC infants have a higher abundance of waterborne bacteria. Therefore, attention should be paid to the contamination of water sources and various ventilator pipelines for premature infants hospitalized in the neonatal intensive care unit.3. An in-depth study of the mode of microbial colonization in premature infants combined with the different functions of various metabolic pathways involved in different microorganisms may be able to identify the cause of NEC.

背景：本研究的目的是探究肠道微生物群与坏死性小肠结肠炎（NEC）之间的关系。方法：采用16S rRNA基因测序技术比较粪便的微生物组成。首次样本采集于出生后48小时内，之后每周一次，直至NEC诊断，最终在治疗后的1-2周或出生后的28天内进行。结果：NEC组微生物群的α多样性高于对照组。β多样性分析显示，对照组在NEC发病初期具有更高的相似性，而NEC组则分布于多个亚组。线性判别分析效应量和分类组成分析表明，NEC婴儿出生时拟杆菌和放线菌的丰度远高于对照组，并且这一趋势持续至NEC发生。此时，放线菌目、 Dysgonomonas、Ochrobactrum、Ralstonia、Pelomonas、Acinetobacter等在NEC婴儿中也更为丰富。NEC组上调的不同代谢途径主要集中在降解/利用/同化、生物合成以及前体代谢物和能量的生成。结论：1. 微生物群根据NEC诊断的时间而不同（限定于20天内）。2. 没有任何单一的微生物与NEC相关，多种物种的联合作用在NEC的发生中具有重要意义。早产儿容易受到环境中细菌的影响，与普通早产儿相比，NEC婴儿的水生细菌丰度更高。因此，应关注新生儿重症监护病房住院早产儿的水源和各类呼吸管道的污染。3. 对早产儿微生物定植方式的深入研究，并结合不同微生物所涉及的各类代谢途径的不同功能，或许能够识别NEC的病因。