Spatial and Temporal Analysis of the Stomach and Small-Intestinal Microbiota in Fasted Healthy Humans

ABSTRACTAlthough the microbiota in the proximal gastrointestinal (GI) tract have been implicated in health and disease, much about these microbes remains understudied compared to those in the distal GI tract. This study characterized the microbiota across multiple proximal GI sites over time in healthy individuals. As part of a study of the pharmacokinetics of oral mesalamine administration, healthy, fasted volunteers (n = 8; 10 observation periods total) were orally intubated with a four-lumen catheter with multiple aspiration ports. Samples were taken from stomach, duodenal, and multiple jejunal sites, sampling hourly (≤7 h) to measure mesalamine (administered att = 0), pH, and 16S rRNA gene-based composition. We observed a predominance ofFirmicutesacross proximal GI sites, with significant variation compared to stool. The microbiota was more similar within individuals over time than between subjects, with the fecal microbiota being unique from that of the small intestine. The stomach and duodenal microbiota displayed highest intraindividual variability compared to jejunal sites, which were more stable across time. We observed significant correlations in the duodenal microbial composition with changes in pH; linear mixed models identified positive correlations with multipleStreptococcusoperational taxonomic units (OTUs) and negative correlations with multiplePrevotellaandPasteurellaceaeOTUs. Few OTUs correlated with mesalamine concentration. The stomach and duodenal microbiota exhibited greater compositional dynamics than the jejunum. Short-term fluctuations in the duodenal microbiota were correlated with pH. Given the unique characteristics and dynamics of the proximal GI tract microbiota, it is important to consider these local environments in health and disease states.IMPORTANCEThe gut microbiota are linked to a variety of gastrointestinal diseases, including inflammatory bowel disease. Despite this importance, microbiota dynamics in the upper gastrointestinal tract are understudied. Our article seeks to understand what factors impact microbiota dynamics in the healthy human upper gut. We found that the upper gastrointestinal tract contains consistently prevalent bacterial OTUs that dominate the overall community. Microbiota variability is highest in the stomach and duodenum and correlates with pH.

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Spatial and Temporal Analysis of the Stomach and Small Intestinal Microbiota in Fasted Healthy Humans

10.1101/450221 ◽

2018 ◽

Author(s):

Anna M. Seekatz ◽

Matthew K. Schnizlein ◽

Mark J. Koenigsknecht ◽

Jason R. Baker ◽

William L. Hasler ◽

...

Keyword(s):

Temporal Analysis ◽

Fecal Microbiota ◽

Individual Variability ◽

Rrna Gene ◽

Gi Tract ◽

Microbial Composition ◽

Healthy Humans ◽

Lumen Catheter ◽

Health And Disease ◽

Over Time

AbstractAlthough the microbiota in the proximal gastrointestinal (GI) tract has been implicated in health and disease, much of these microbes remains understudied compared to the distal GI tract. This study characterized the microbiota across multiple proximal GI sites over time in healthy individuals.As part of a study of the pharmacokinetics of oral mesalamine administration, healthy, fasted volunteers (N=8; 10 observation periods total) were orally intubated with a four-lumen catheter with multiple aspiration ports. Samples were taken from stomach, duodenal, and multiple jejunal sites, sampling hourly (≤7 hours) to measure mesalamine (administered at t=0), pH, and 16S rRNA gene-based composition.We observed a predominance of Firmicutes across proximal GI sites, with significant variation compared to stool. The microbiota was more similar within individuals over time than between subjects, with the fecal microbiota being unique from that of the small intestine. The stomach and duodenal microbiota displayed highest intra-individual variability compared to jejunal sites, which were more stable across time. We observed significant correlations in the duodenal microbial composition with changes in pH; linear mixed models identified positive correlations with multipleStreptococcusoperational taxonomic units (OTU) and negative correlations with multiplePrevotella and PasteurellaceaeOTUs. Few OTUs correlated with mesalamine concentration.The stomach and duodenal microbiota exhibited greater compositional dynamics compared to the jejunum. Short-term fluctuations in the duodenal microbiota was correlated with pH. Given the unique characteristics and dynamics of the proximal GI tract microbiota, it is important to consider these local environments in health and disease states.

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Ecological Succession of Bacterial Communities during Conventionalization of Germ-Free Mice

Applied and Environmental Microbiology ◽

10.1128/aem.05239-11 ◽

2012 ◽

Vol 78 (7) ◽

pp. 2359-2366 ◽

Cited By ~ 39

Author(s):

Merritt G. Gillilland ◽

John R. Erb-Downward ◽

Christine M. Bassis ◽

Michael C. Shen ◽

Galen B. Toews ◽

...

Keyword(s):

Bacterial Community ◽

16S Rrna ◽

Bacterial Communities ◽

Structural Heterogeneity ◽

Ecological Succession ◽

Rrna Gene ◽

Gi Tract ◽

Content Type ◽

Germ Free ◽

Over Time

ABSTRACTLittle is known about the dynamics of early ecological succession during experimental conventionalization of the gastrointestinal (GI) tract; thus, we measured changes in bacterial communities over time, at two different mucosal sites (cecum and jejunum), with germfree C57BL/6 mice as the recipients of cecal contents (input community) from a C57BL/6 donor mouse. Bacterial communities were monitored using pyrosequencing of 16S rRNA gene amplicon libraries from the cecum and jejunum and analyzed by a variety of ecological metrics. Bacterial communities, at day 1 postconventionalization, in the cecum and jejunum had lower diversity and were distinct from the input community (dominated by eitherEscherichiaorBacteroides). However, by days 7 and 21, the recipient communities had become significantly diverse and the cecal communities resembled those of the donor and donor littermates, confirming that transfer of cecal contents results in reassembly of the community in the cecum 7 to 21 days later. However, bacterial communities in the recipient jejunum displayed significant structural heterogeneity compared to each other or the donor inoculum or the donor littermates, suggesting that the bacterial community of the jejunum is more dynamic during the first 21 days of conventionalization. This report demonstrates that (i) mature input communities do not simply reassemble at mucosal sites during conventionalization (they first transform into a “pioneering” community and over time take on the appearance, in membership and structure, of the original input community) and (ii) the specific mucosal environment plays a role in shaping the community.

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Upper gastrointestinal bleeding as a complication of intracranial disease

Journal of Neurosurgery ◽

10.3171/jns.1972.37.1.0027 ◽

1972 ◽

Vol 37 (1) ◽

pp. 27-29 ◽

Cited By ~ 18

Author(s):

Steven B. Karch

Keyword(s):

Gastrointestinal Tract ◽

Gastrointestinal Bleeding ◽

Upper Gastrointestinal Bleeding ◽

Upper Gastrointestinal Tract ◽

Duodenal Ulcers ◽

Content Type ◽

Intracranial Disease ◽

Esophageal Ulceration ◽

Upper Gastrointestinal ◽

Fine Print

✓ Review of 2206 consecutive necropsies showed evidence of hemorrhagic ulceration of the upper gastrointestinal tract in 7.2%. The incidence in patients dying from intracranial disorders was found to be twice that of those dying from all other causes (12.5% vs 6.0%). The distribution of lesions within the two groups was also different in that esophageal ulceration was more common in the neurological group (p < .001), while duodenal ulcers were more common in the non-neurological group (p < .001).

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Gastroscopy in Pediatric Surgery: Indications, Complications, Outcomes, and Ethical Aspects

Gastroenterology Research and Practice ◽

10.1155/2015/820340 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8

Author(s):

Louise Roth ◽

Martin Salö ◽

Mette Hambraeus ◽

Pernilla Stenström ◽

Einar Arnbjörnsson

Keyword(s):

Gastrointestinal Tract ◽

Pediatric Surgery ◽

Upper Gastrointestinal Tract ◽

Care Planning ◽

Ethical Aspects ◽

Health Care Planning ◽

Laparoscopic Gastrostomy ◽

Time Periods ◽

Upper Gastrointestinal ◽

Over Time

Background.The aim of this study was to map gastroscopies performed at a single tertiary pediatric surgery centre to investigate indications, complications, outcomes, and ethical aspects.Material and Methods.A retrospective study of gastroscopies performed during two time periods (2001–2004 and 2011–2014) was conducted. Data regarding indications, outcomes, and complications of pediatric gastroscopies were analysed from a prospectively collected database.Results.The indications for gastroscopies changed over time. Therefore, 376 gastroscopies performed from 2011 through 2014 were studied separately. The median patient was four years old. The predominant indications were laparoscopic gastrostomy (40%), investigation of gastroenterological conditions (22%), obstruction in the upper gastrointestinal tract (20%), gastroesophageal reflux disease (GERD) (15%), and other indications (3%). Percentages of gastroscopies with no positive findings for each condition were laparoscopic gastrostomy, 100%; gastroenterological conditions, 46%; obstruction in the upper gastrointestinal tract, 36%; GERD, 51%. Furthermore, gastroscopies did not lead to any further action or change in treatment in 45% of gastroenterological conditions and 72% of GERD cases. The overall complication rate was 1%.Conclusion.The results are valuable to educate pediatric surgeons and to inform health care planning when including gastroscopy within clinical practice.

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Comparison of the Endoscopic Picture in Case of Complications of the upper Gastrointestinal Tract Caused by the Use of Antithrombotic Agents and Non-Steroidal Anti-Inflammatory Drugs

Acta biomedica scientifica ◽

10.29413/abs.2019-4.5.3 ◽

2019 ◽

Vol 4 (5) ◽

pp. 19-25

Author(s):

E. V. Moroz ◽

A. Y. Karateev ◽

E. V. Kryukov ◽

A. A. Sokolov ◽

E. N. Artemkin

Keyword(s):

Gastric Ulcer ◽

Gastrointestinal Tract ◽

Upper Gastrointestinal Tract ◽

Gastric Ulcers ◽

Gi Tract ◽

Gastroduodenal Mucosa ◽

Inflammatory Drugs ◽

Anti Inflammatory ◽

Endoscopic Picture ◽

Upper Gastrointestinal

Intaking antithrombotic funds (ATA) and non-steroidal anti-inflammatory drugs (NSAIDs) is one of the most frequent causes of pathology in gastrointestinal (GI) tract.The purpose of the study: comparison of pathological changes of the mucous membrane in the upper GI tract, that occur against the background of ATA and NSAIDs admission.Material and methods. Endoscopic data of two groups of patients taking ATA and NSAIDS have been compared. The first group of 448 patients from the 10th Gastrointestinal Department in N.N. Burdenko Main Military Clinical Hospital was on record from 2013 to 2017. The patients had erosive ulcerous changes of gastrointestinal mucosa, occurred against the background of the ATA admission. The second group comprised 6431 patients with rheumatic diseases. They were hospitalized in the clinic of V.A. Nasonova Research Institute of Rheumatology in the period from 2007 to 2016 and took NSAIDs regularly.Results. Duodenal and gastric ulcer changes in gastric mucosa and duodenal ulcers were identified in 168 (37.5 %) patients taking ATA and in 1691 (26.3 %) patient treated with NSAIDS. Structure of pathology varied. So, against the background of ATA and NSAIDS admission, the number of acute gastric ulceration amounted to 6.5 % and 15.5 % (p < 0.001); acute ulcers duodenal was 2.9 % and 4.9 %; combined ulcerative lesions of gastric and duodenal was 2.9 % and 2.0 %; multiple erosions of gastroduodenal mucosa were 52.4 % and 15.7 % (p < 0.001); single erosion was 35. 1% and 61.6 %. The factor of ulcer history and age ≥ 65 years old increased significantly the risk of duodenal and gastric ulcer changes in patients taking ATA and NSAIDs: OR 5.182 (95% CI 2.701–9.942) and 3.24 (95% CI 2.19–5.34), 4.537 (95% CI 2.036–10.11) and 2.016 (95% CI 1.230–2.917) respectively. Intaking of proton pump inhibitor (PPI) reduced significantly the risk of complications for both ATA and NSAIDs: OR 0.329 (95% CI 0.199–0.546) and 0.317 (95% CI 0.210–0.428) respectively.Conclusion. The structure of pathology of mucous in the upper gastrointestinal tract that arose against the backdrop of ATA and NSAIDs admission is different. The first is characterized by a multiple erosion, while the second one has single acute distal gastric ulcers. The ulcerative history and advanced age of patients increase significantly the risk of complications concerning the gastroduodenal mucosa when using ATA and NSAIDs. PPI is the effective means of preventing this pathology.

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