基于MiSeq高通量测序技术对 3个孝感凤窝酒曲细菌多样性的评价

目的对凤窝酒曲细菌多样性进行研究。方法选取孝感地区3个凤窝酒曲作为研究对象,采用MiSeq高通量测序技术以16S rRNA为靶点,对其细菌菌群构成进行研究。结果 3个凤窝酒曲中发现9个优势核心属,其相对含量累计为78.15%,发现10个相对含量大于1.0%的分类操作单元,累计相对含量为60.62%。结论 3个凤窝酒曲共有大量的核心细菌菌群。     

丢糟窖窖泥细菌多样性评价

目的对丢糟窖窖泥细菌多样性进行评价。方法选取3个丢糟窖窖池为研究对象,每个窖池分别从上、中和下部取样,采用MiSeq高通量测序技术以16SrRNA为靶点,从分类操作单元(operational taxonomic units,OTU)分布、菌群分类学地位、核心OTU、菌群α和β多样性等维度对其细菌多样性进行研究。结果在门水平上,Firmicutes和Actinobacteria的平均含量分别为93.89%和4.73%。在属水平上,Lactobacillus、Clostridium、Bacillus、Paenibacillus和Thermoactinomyces的平均相对含量分别为59.67%、8.28%、5.73%、4.97%和1.29%。发现7个平均相对含量大于1.0%的核心OTU,累计相对含量为63.30%。结论丢糟窖窖泥中的细菌主要由隶属于Firmicutes的5个属构成,不同样品间共有大量的核心菌群。     

益生菌Lactobacillus paracasei subsp.paracasei Zhang对海南地区部分青年人肠道菌群的影响

【目的】以海南地区征集的29名健康青年志愿者为研究对象,分析该地区青年人肠道菌群多样性,并探究益生菌Lactobacillus paracasei subsp. paracasei Zhang (LCZ)对其肠道菌群的影响。【方法】29名健康青年志愿者每日补充2 g益生菌LCZ (0.5×10~(10)CFU/g),为期14 d。采集摄入益生菌LCZ第0、14、28天的志愿者粪便样品,采用Pac Bio SMRT测序技术基于16S rRNA基因全长测序分析志愿者粪便微生物组成和结构,评估益生菌LCZ对其肠道菌群的影响。【结果】在门水平上,Firmicutes (54.46%)和Bacteroidetes (33.79%)在志愿者粪便微生物中含量最高;在属水平上,Bacteroides (23.13%)的相对含量最高;在种水平上,优势菌种为Faecalibacterium prausnitzii (9.72%)、Eubacterium rectale (7.00%)和Prevotella copri (6.07%)等。摄入益生菌LCZ 14 d后,肠道中的优势菌属变化不显著,低丰度菌属如Oscillospira和Parabacteroides等显著增加,Aeromonas和Fusicatenibacter等显著减少(P0.05)。此外根据志愿者粪便中Lactobacillus含量的变化情况,将所有志愿者分为两组。其中一组志愿者在摄入LCZ后粪便中Lactobacillus菌属相对含量显著增加,同时该组志愿者肠道中其他菌种如Butyricicoccus pullicaecorum、Lactococcus raffinolactis和Parabacteroides distasoni亦显著增加;而另一组志愿者,Lactobacillus及上述菌种均未发生显著变化。【结论】连续2周摄入益生菌LCZ对志愿者肠道菌群中优势菌属的相对丰度影响不显著,但对低丰度菌属的相对丰度影响显著。     

中西部幼儿肠道菌群与膳食关系的比较

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。     

基于PacBio SMRT测序技术评估妊娠期糖尿病人的肠道菌群

[目的]肠道菌群是位于人体肠道内的微生物菌群,其组成与人类多种疾病相关。例如,已有研究表明肠道菌群的变化与妊娠期糖尿病（gestational diabetes mellitus,GDM）的发病密切相关。因此本研究基于PacBio SMRT测序技术评估及比较了不同民族（汉族和蒙古族）及是否患GDM的孕妇的肠道菌群。[方法]本研究利用PacBio SMRT测序技术对97例患有GDM及健康的汉族和蒙古族孕妇粪便样本进行了全长16S rRNA测序及分析。[结果]总体来说,处于相同孕期的4组孕妇肠道菌群的组成相似,不同核心菌群展现出不同强弱的相关性。本研究在种的水平上共鉴定到了44个种。在汉族人中,患有妊娠期糖尿病的孕妇肠道菌群中Akkermansia muciniphila菌的相对丰度要显著低于健康孕妇;而在蒙古族人中,健康孕妇与GDM孕妇间差异并不明显。在健康对照中发现汉族孕妇肠道菌群中Bacteroides uniformis菌的相对丰度显著高于蒙古族孕妇;但在患有GDM组中未找到不同民族分组间的差异。另外,功能预测结果发现四组样本菌群功能组成高度相似,大多数功能基因都与能量代谢有关。汉族GDM患者与健康对照组间没有发现显著差异,但在蒙古族GDM患者中发现无机离子运输等功能相对丰度显著高于与蒙古族正常孕妇。[结论]在相同的孕期,妊娠期孕妇的核心肠道菌群结构与功能是相对稳定的,而民族差异也不会对妊娠期菌群产生显著性影响。但在四组间可以检测到一些低丰度的差异菌群,如Akkermansia muciniphila,其丰度的变化可能导致了肠道中一些与肠道营养吸收等有关的代谢发生变化,而这些变化可能与妊娠期糖尿病的发生密切相关。本研究将有助于探究肠道菌群在GDM发病机制中的作用。     

黎族人肠道微生物群落结构特征及其与饮食关联性

【目的】对采集自海南省白沙地区的黎族健康志愿者肠道菌群进行研究,旨在揭示黎族人肠道微生物群落结构特征及其与饮食的相关性。【方法】以海南省白沙黎族自治县征集的22名志愿者晨便为研究对象,应用基于16S r RNA基因V3–V4可变区的高通量测序技术测定其肠道菌群组成,并与其他民族肠道菌群进行比较分析,详细记录黎族22名志愿者的营养物质摄入情况,探索其肠道微生物群落结构特征及其与饮食的相关性。【结果】在门水平上,拟杆菌门(Bacteroidetes,58.96%)和硬壁菌门(Firmicutes,37.77%)在黎族志愿者肠道内含量最高;在属的水平上,普氏菌属(Prevotella,49.38%)在黎族健康志愿者肠道内含量最高。基于微生物群落α和β多样性的分析结果表明,黎族人肠道菌群与中国其他民族人群肠道菌群呈现出显著差异且α多样性显著低于其他民族,特征性差异菌属为:链型杆菌属(Catenibacterium)、普氏菌属(Prevotella)、巨型球菌属(Megasphaera)、巨单胞菌属(Megamonas)、考拉杆菌属(Phascolarctobacterium)和布劳特氏菌属(Blautia)。基于肠道核心微生物与营养物质相关性的研究显示,普氏粪杆菌(Faecalibacterium prausnitzii)与膳食纤维、Cu、Mg和Mn的摄入量呈现显著正相关,与脂肪和VB2的摄入量呈现显著负相关,而罗氏乳杆菌(Lactobacillus rogosae)与膳食纤维、Zn和Fe的摄入量呈显著正相关,与烟酸摄入量呈显著负相关。【结论】揭示了肠道微生物在不同地域和民族之间的差异,研究结果提供了一种通过膳食来优化菌群结构、调控宿主肠道微生态平衡的新思路。     

西方蜜蜂工蜂肠道菌群定殖起始点和定殖稳态点的结构比较分析

【目的】目前,针对昆虫肠道细菌定殖规律的研究还未见报道。探索西方蜜蜂(Apis mellifera)肠道菌群定殖过程两个重要时间节点(起始0日龄和稳态7日龄)间肠道细菌群落(菌群)结构组成的差异,加深对蜜蜂及昆虫肠道菌群定殖规律的认识。【方法】分别采集两个化蛹后工蜂发育阶段的个体各5只,分别解剖并提取其肠道菌群DNA。使用Illumina技术对肠道菌群16S rD NA高变区进行高通量测序。通过生物信息学的分析方法对肠道菌群进行多样性分析,并对两个时间点相对丰度最高的肠道菌群进行统计分析,比较肠道菌群相对丰度和组成的差异。【结果】共获得515156条高质量序列,长度为227904953bp,平均长度为442bp。基于OTUs的分类表明,工蜂肠道细菌分别隶属于34个门82个纲221个目405个科799个属。此外,工蜂肠道菌群定殖起点和终点间的Alpha多样性指数存在显著差异(ACE,P=0.0014;Chao,P=0.0013;Shannon,P=0.0003;Simpson,P=0.0028,Student’s t检验)。此外,相较0日龄工蜂,7日龄工蜂肠道中的乳酸杆菌Lactobacillus、Gilliamella、双歧杆菌Bifidobacterium、Snodgrassella4个属的相对丰度显著增加;相反,不动杆菌Acinetobacter、大肠杆菌志贺氏菌Escherichia-Shigella、鞘脂单胞菌Sphingomonas、类杆菌Bacteroides、涅斯捷连科氏菌Nesterenkonia、栖热菌Thermus6个属的细菌相对丰度显著降低(P0.05)。【结论】出房(0日龄)成年工蜂的肠道菌群多样性显著高于菌群定殖完成(7日龄)工蜂的肠道菌群多样性,且成年工蜂肠道菌群定殖完成前后部分类群的相对丰度显著改变。本研究的结果不仅可增加我们对蜜蜂肠道菌群定殖规律的认识,也能够为研究其他昆虫肠道菌群的定殖规律提供重要的参考信息。     

二甲酸钾对白羽肉鸡生长性能和肠道菌群结构的影响

为评估二甲酸钾对畜禽肠道菌群的影响及其作为一种抗饲料添加剂的应用潜力,采用3日龄健康白羽肉鸡作为饲喂对象,在基础饲粮基础上添加质量浓度为0.1%、0.3%、0.5%、0.7%的二甲酸钾和含量为50 mg/mL的金霉素分别进行比较饲喂管理。记录28 d试验周期内白羽肉鸡的料重比变化,采集28 d时白羽肉鸡盲肠肠道内溶物,利用第三代测序技术对肠道菌群进行16S rDNA全长序列高通量测序。结果显示,饲喂0.3%的二甲酸钾能够显著降低料重比,对白羽肉鸡的生长性能具有明显的促进作用。饲喂0.3%的二甲酸钾对白羽肉鸡的肠道菌群结构造成了一定的影响,有效地提高了肠道菌群的物种多样性。优势菌群中,饲喂0.3%二甲酸钾与空白组相比,在门水平上,拟杆菌门相对丰度显著上升,厚壁菌门、变形菌门和Epsilonbacteraeota的相对丰度下降,产生了更有利于生长发育的微生物群落。同时,在属水平上,拟杆菌属相对丰度显著上升, Barnesiella和螺杆菌属的相对丰度下降,改善了肠道中微生物菌群的微生态健康。研究结果丰富了二甲酸钾和金霉素对白羽肉鸡生长性能和肠道菌群影响的认识,也为更全面了解二甲酸钾应用于替代抗生素对畜禽的影响提供了有价值的微生物学信息。     

粪便留取量对粪便中细菌结构和功能的影响CSCD

目的探究不同粪便留取量对肠道菌群构成研究结果的影响,为肠道菌群构成研究中粪便样本的采集方式提供参考。方法本研究分别对全便和部分粪便进行预处理,并使用PacBio SMRT测序技术对10名志愿者的20份粪便样本进行了16S rRNA全长测序,通过多元统计学等手段对粪便中细菌的构成、多样性和功能进行比较分析。结果Eubacterium rectale、Eubacterium ventriosum和Allisonella histaminiformans等低丰度物种的相对丰度在不同粪便留取量中有一定差异,其在全便中的相对丰度均显著高于部分粪便(P<0.05)。但Wilcoxon配对检验发现粪便留取量对肠道菌群结构、多样性和功能的影响均无显著性差异(P>0.05)。不同个体间肠道菌群结构存在明显差异,且粪便留取量的影响远小于个体差异。结论全便和部分粪便两种粪便留取量对检测微生物的组成、多样性和功能无显著影响,因此取部分粪便即可满足对肠道菌群研究的要求。     

人工饲喂对长尾仓鼠肠道菌群组成的影响

食物变化是引起小型哺乳动物肠道菌群改变的关键因素。野生动物由野外转至室内饲养会经历剧烈的生活方式变化,而目前对人工饲喂驱动其肠道微生物群落结构的演替过程还不完全了解。为明确人工饲喂对小型哺乳动物肠道菌群组成的影响,于2022年夏季(7—9月)在山西省吕梁市离石区(LS)、临汾市隰县(XX)、晋中市左权县(ZQ) 3个地区应用笼捕法捕获长尾仓鼠(Cricetulus longicaudatus)活体,基于16S rDNA测序技术分析不同生态环境中其肠道菌群的差异,并探究相同人工饲喂条件下长尾仓鼠肠道菌群的演替过程。结果表明：长尾仓鼠肠道菌群在野外环境中,XX和ZQ种群的厚壁菌门显著富集,LS种群的拟杆菌门显著富集,肠单胞球菌属(Intestinimonas)为3个种群的共有优势属。相同人工饲喂35 d后,拟杆菌门在3个种群显著富集且相对丰度趋于一致,ZQ种群Muribaculacea的相对丰度为48.85%,显著高于野外环境。本研究说明不同生态环境中长尾仓鼠肠道菌群具有差异性。经长期相同人工饲喂后,其肠道菌群的相似性显著增加,说明饮食变化对长尾仓鼠肠道菌群多样性及群落组成具有较大影响,而...     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

Scurvy in capybaras bred in captivity in Argentine

In order to determine if the absence of vitamin C in the diet of capybaras (Hydrochoerus hydrochaeris) causes scurvy, a group of seven young individuals were fed food pellets without ascorbic acid, while another group of eight individuals received the same food with 1 g of ascorbic acid per animal per day. Animals in the first group developed signs of scurvy-like gingivitis, breaking of the incisors and death of one animal. Clinical signs appeared between 25 and 104 days from the beginning of the trial in all individuals. Growth rates of individuals deprived of vitamin C was considerably less than those observed in the control group. Deficiency of ascorbic acid had a severe effect on reproduction of another population of captive capybaras. We found that the decrease in ascorbic acid content in the diet affected pregnancy, especially during the first stages. The results obtained suggest that it is necessary to supply a suitable quantity of vitamin C in the diet of this species in captivity.     

Changes in lactate dehydrogenase activity in chicken tissues in hyperthyreosis in ontogenesis

The lactate dehydrogenase activity in reactions of lactate oxidation and synthesis was studied in subfractions of the chicken brain, heart and liver at the embryonal, early postembryonal and adult stages of development after thyroxine administration. It has been shown that during embryogenesis thyroxine predominantly enhanced the rate of lactate oxidation in the mitochondrial tissues. A marked increase in the lactate synthesis was found in cytoplasm of the adult chicken tissues. Specificity of enzyme activity alterations was detected in the chicken brain during ontogenesis after thyroxine administration.     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.