| 1. |
- Thorell, Kaisa, et al.
(författare)
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Isolates from Colonic Spirochetosis in Humans Show High Genomic Divergence and Potential Pathogenic Features but Are Not Detected Using Standard Primers for the Human Microbiota
- 2019
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Ingår i: Journal of Bacteriology. - 0021-9193 .- 1098-5530. ; 201:21
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Tidskriftsartikel (refereegranskat)abstract
- Colonic spirochetosis, diagnosed based on the striking appearance in histological sections, still has an obscure clinical relevance, and only a few bacterial isolates from this condition have been characterized to date. In a randomized, population-based study in Stockholm, Sweden, 745 healthy individuals underwent colonoscopy with biopsy sampling. Of these individuals, 17 (2.3%) had colonic spirochetosis, which was associated with eosinophilic infiltration and a 3-fold-increased risk for irritable bowel syndrome (IBS). We aimed to culture the bacteria and perform whole-genome sequencing of the isolates from this unique representative population sample. From 14 out of 17 individuals with spirochetosis we successfully isolated, cultured, and performed whole-genome sequencing of in total 17 isolates, including the Brachyspira aalborgi type strain, 513A. Also, 16S analysis of the mucosaassociated microbiota was performed in the cases and nonspirochetosis controls. We found one isolate to be of the species Brachyspira pilosicoli; all remaining isolates were of the species Brachyspira aalborgi. Besides displaying extensive genetic heterogeneity, the isolates harbored several mucin-degrading enzymes and other virulenceassociated genes that could confer a pathogenic potential in the human colon. We also showed that 16S amplicon sequencing using standard primers for human microbiota studies failed to detect Brachyspira due to primer incompatibility. IMPORTANCE This is the first report of whole-genome analysis of clinical isolates from individuals with colonic spirochetosis. This characterization provides new opportunities in understanding the physiology and potentials of these bacteria that densely colonize the gut in the individuals infected. The observation that standard 16S amplicon primers fail to detect colonic spirochetosis may have major implications for studies searching for associations between members of the microbiota and clinical conditions such as irritable bowel syndrome (IBS) and should be taken into consideration in project design and interpretation of gastrointestinal tract microbiota in population-based and clinical settings.
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| 2. |
- Carstens, Adam, 1975-, et al.
(författare)
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The Gut Microbiota in Collagenous Colitis Shares Characteristics With Inflammatory Bowel Disease-Associated Dysbiosis
- 2019
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Ingår i: Clinical and Translational Gastroenterology. - : Nature Publishing Group. - 2155-384X. ; 10:7
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: In inflammatory bowel disease (IBD), an aberrant immune response to gut microbiota is important, but the role of the microbiota in collagenous colitis (CC) is largely unknown. We aimed to characterize the microbiota of patients with CC compared with that of healthy control and patients with IBD.METHODS: Fecal samples were collected from patients with CC (n = 29), age- and sex-matched healthy controls (n = 29), patients with Crohn's disease (n = 32), and patients with ulcerative colitis (n = 32). Sequence data were obtained by 454 sequencing of 16S rRNA gene amplicons, and the obtained sequences were subsequently taxonomically classified.RESULTS: Analysis of similarity statistics showed a segregation between patients with CC and healthy controls with increasing taxonomic resolution, becoming significant comparing operational taxonomic unit data (P = 0.006). CC had a lower abundance of 10 different taxa. Taxa-specific analyses revealed a consistent lower abundance of several operational taxonomic units belonging to the Ruminococcaceae family in patients with CC, q < 0.05 after false discovery rate correction. Loss of these taxa was seen in patients with CC with active disease and/or corticosteroid treatment only and resembled the findings in patients with IBD.DISCUSSION: CC is associated with a specific fecal microbiome seen primarily in patients with active disease or ongoing corticosteroid treatment, whereas the microbiome of CC patients in remission resembled that of healthy controls. Notably, the shift in key taxa, including the Ruminococcaceae family, was also observed in IBD. There may be common mechanisms in the pathogenesis of CC and IBD.
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| 3. |
- Abdellah, Tebani, et al.
(författare)
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Integration of molecular profiles in a longitudinal wellness profiling cohort.
- 2020
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- An important aspect of precision medicine is to probe the stability in molecular profiles among healthy individuals over time. Here, we sample a longitudinal wellness cohort with 100 healthy individuals and analyze blood molecular profiles including proteomics, transcriptomics, lipidomics, metabolomics, autoantibodies andimmune cell profiling, complementedwith gut microbiota composition and routine clinical chemistry. Overall, our results show high variation between individuals across different molecular readouts, while the intra-individual baseline variation is low. The analyses show that each individual has a unique and stable plasma protein profile throughout the study period and that many individuals also show distinct profiles with regards to the other omics datasets, with strong underlying connections between the blood proteome and the clinical chemistry parameters. In conclusion, the results support an individual-based definition of health and show that comprehensive omics profiling in a longitudinal manner is a path forward for precision medicine.
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| 4. |
- Berntson, Lillemor, 1957-, et al.
(författare)
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A Pilot Study Investigating Faecal Microbiota After Two Dietary Interventions in Children with Juvenile Idiopathic Arthritis
- 2022
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Ingår i: Current Microbiology. - : Springer Science and Business Media LLC. - 0343-8651 .- 1432-0991. ; 79:7
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Tidskriftsartikel (refereegranskat)abstract
- There is evidence for an impact of the gut microbiota on the immune system, which has consequences for inflammatory diseases. Exclusive enteral nutrition (EEN) and the specific carbohydrate diet (SCD) have been demonstrated as effective anti-inflammatory treatments for children with Crohn’s disease. We have previously shown an anti-inflammatory effect from these nutritional treatments in children with juvenile idiopathic arthritis (JIA). The aim of this study was to investigate if improved clinical symptoms after EEN or SCD treatment in children with JIA could be linked to changes in faecal microbiota. We included sixteen patients with JIA (age 7–17 years), six for treatment with EEN and ten with SCD. EEN was given for 3–5 weeks and SCD for 4–5 weeks, with clinical and laboratory status assessed before and after treatment. Faecal samples were analysed for microbiota diversity and composition using 16S rRNA gene sequencing. Analyses of the faecal microbiota showed an effect on the overall composition with both interventions; the most striking result was a decreased relative abundance of the genus Faecalibacterium from EEN and of Bifidobacterium from SCD. The α-diversity decreased significantly from SCD (P = 0.04), but not from EEN (P = 0.22). Despite the study cohorts being small, both EEN and SCD were shown to impact the faecal microbiota. Future larger studies with a focus on metagenomics or metabolomics could possibly reveal a link and clarify the clinical effects of those nutritional regimens.
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| 5. |
- Dicksved, Johan, et al.
(författare)
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Molecular characterization of the stomach microbiota in patients with gastric cancer and in controls
- 2009
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Ingår i: Journal of Medical Microbiology. - : Microbiology Society. - 0022-2615 .- 1473-5644. ; 58:4, s. 509-516
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Tidskriftsartikel (refereegranskat)abstract
- Persistent infection of the gastric mucosa by Helicobacter pylori can initiate an inflammatory cascade that progresses into atrophic gastritis, a condition associated with reduced capacity for secretion of gastric acid and an increased risk of developing gastric cancer. The role of H. pylori as an initiator of inflammation is evident but the mechanism for development into gastric cancer has not yet been proven. A reduced capacity for gastric acid secretion allows survival and proliferation of other microbes that normally are killed by the acidic environment. It has been postulated that some of these species may be involved in the development of gastric cancer; however, their identities are poorly defined. In this study, the gastric microbiota from ten patients with gastric cancer was characterized and compared with that from five dyspeptic controls using the molecular profiling approach terminal restriction fragment length polymorphism (T-RFLP), in combination with 16S rRNA gene cloning and sequencing. T-RFLP analysis revealed a complex bacterial community in the cancer patients that was not significantly different from that in the controls. Sequencing of 140 clones revealed 102 phylotypes, with representatives from five bacterial phyla (Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria). The data revealed a relatively low abundance of H. pylori and showed that the gastric cancer microbiota was instead dominated by different species of the genera Streptococcus, Lactobacillus, Veillonella and Prevotella. The respective role of these species in development of gastric cancer remains to be determined.
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| 6. |
- Dicksved, Johan, et al.
(författare)
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Susceptibility to Campylobacter Infection Is Associated with the Species Composition of the Human Fecal Microbiota
- 2014
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Ingår i: mBio. - 2161-2129 .- 2150-7511. ; 5:5, s. e01212-14-
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Tidskriftsartikel (refereegranskat)abstract
- The gut microbiota is essential for human health, but very little is known about how the composition of this ecosystem can influence and respond to bacterial infections. Here we address this by prospectively studying the gut microbiota composition before, during, and after natural Campylobacter infection in exposed poultry abattoir workers. The gut microbiota composition was analyzed with 16S amplicon sequencing of fecal samples from poultry abattoir workers during the peak season of Campylobacter infection in Sweden. The gut microbiota compositions were compared between individuals who became culture positive for Campylobacter and those who remained negative. Individuals who became Campylobacter positive had a significantly higher abundance of Bacteroides (P = 0.007) and Escherichia (P = 0.002) species than those who remained culture negative. Furthermore, this group had a significantly higher abundance of Phascolarctobacterium (P = 0.017) and Streptococcus (P = 0.034) sequences than the Campylobacter-negative group, which had an overrepresentation of Clostridiales (P = 0.017), unclassified Lachnospiraceae (P = 0.008), and Anaerovorax (P = 0.015) sequences. Intraindividual comparisons of the fecal microbiota compositions yielded small differences over time in Campylobacter-negative participants, but significant long-term changes were found in the Campylobacter-positive group (P < 0.005). The results suggest that the abundance of specific genera in the microbiota reduces resistance to Campylobacter colonization in humans and that Campylobacter infection can have long-term effects on the composition of the human fecal microbiota. IMPORTANCE Studies using mouse models have made important contributions to our understanding of the role of the gut microbiota in resistance to bacterial enteropathogen colonization. The relative abundances of Escherichia coli and Bacteroides species have been pointed out as important determinants of susceptibility to Gram-negative pathogens in general and Campylobacter infection in particular. In this study, we assessed the role of the human gut microbiota in resistance to Campylobacter colonization by studying abattoir workers that are heavily exposed to these bacteria. Individuals with a certain composition of the gut microbiota became culture positive for Campylobacter. As their microbiotas were characterized by high abundances of Bacteroides spp. and E. coli, well in line with the findings with mouse models, these bacterial species likely play an important role in colonization resistance also in humans.
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| 7. |
- Johansson, Cecilia, et al.
(författare)
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Genomic and Phenotypic Characteristics in Geographically Separated Clinical Campylobacter jejuni ST353CC Isolates
- 2021
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Ingår i: Microorganisms. - : MDPI. - 2076-2607. ; 9:12
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Tidskriftsartikel (refereegranskat)abstract
- Campylobacter jejuni fecal isolates of eight international travelers, 5 of which had traveled to Ecuador and 3 to Bangladesh, were characterized, and the possible relationship between bacterial traits and clinical symptoms was further analyzed. All eight isolates belonged to the same Multi-Locus Sequence Type clonal complex (ST353CC). The three isolates from Bangladesh were all of the same sequence type (ST-9438), and when compared to isolates of various other sequence types, they had a larger quantity of unique genetic content, higher expression levels of some putative virulence genes involved in adhesion and invasion (flpA, ciaB and iamA), and showed higher adhesion levels to human HT-29 colon cancer cells in an in vitro infection model. However, in contrast to the seemingly higher pathogenic potential of these bacterial isolates, travelers infected with the ST-9438 isolates had no or only very mild symptoms, whereas the other individuals, whose bacterial isolates seemed to have less pathogenic potential, generally reported severe symptoms. When studying the 16S rRNA gene-based fecal microbiota in samples collected prior to travel, there was an individual variation in the relative abundance of the three major bacterial phyla Actinobacteria, Bacteroidetes and Firmicutes, but there were no associations between composition and diversity of microbiota and development of severe symptoms from the infection. It remains to be confirmed by larger studies whether an individual's characteristics such as gut microbiota, might be related to the severity of symptoms in Campylobacter infections.
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| 8. |
- Kampmann, Christian, et al.
(författare)
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Changes to human faecal microbiota after international travel
- 2021
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Ingår i: Travel Medicine and Infectious Disease. - : Elsevier. - 1477-8939 .- 1873-0442. ; 44
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Tidskriftsartikel (refereegranskat)abstract
- Background:The aim was to investigate whether travelling to less-resourced destinations influences the faecal microbiota in generally healthy adults.Method:In this prospective observational study, 47 adults (median age, 24 years; 73% females) travelled from Sweden to distant destinations for 1-12 weeks. Five faecal samples, two before and three after travel, were analysed by 16S amplicon massive parallel sequencing. Subjects had taken no antibiotics within three months of each sampling. Results:The overall composition of the faecal microbiota was not affected by travel. However, when looking at the relative abundance of individual bacterial taxa, Enterobacteriaceae demonstrated a 10-fold increase immediately after the trip as compared to the samples taken before travelling. Conversely, the relative abundance of Christensenellaceae had decreased equally much. Both of these changes were reversible within nine weeks. Conclusions:International travel, even to less-resourced countries, did not appear to alter the overall diversity of human faecal microbiota as studied here after travelling. However, Enterobacteriaceae bacteria, often associated with infection, inflammation and antibiotic resistance, showed dramatically elevated levels, and Christensenellaceae, frequently associated with healthy conditions, demonstrated remarkably declined levels in relative abundance as detected immediately after travel. In both cases, these changes returned to original pre-travel levels within nine weeks.
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| 9. |
- Marabita, Francesco, et al.
(författare)
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Multiomics and digital monitoring during lifestyle changes reveal independent dimensions of human biology and health
- 2022
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Ingår i: Cell Systems. - : Cell Press. - 2405-4712 .- 2405-4720. ; 13:3, s. 241-255.e7
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Tidskriftsartikel (refereegranskat)abstract
- We explored opportunities for personalized and predictive health care by collecting serial clinical measurements, health surveys, genomics, proteomics, autoantibodies, metabolomics, and gut microbiome data from 96 individuals who participated in a data-driven health coaching program over a 16-month period with continuous digital monitoring of activity and sleep. We generated a resource of >20,000 biological samples from this study and a compendium of >53 million primary data points for 558,032 distinct features. Multiomics factor analysis revealed distinct and independent molecular factors linked to obesity, diabetes, liver function, cardiovascular disease, inflammation, immunity, exercise, diet, and hormonal effects. For example, ethinyl estradiol, a common oral contraceptive, produced characteristic molecular and physiological effects, including increased levels of inflammation and impact on thyroid, cortisol levels, and pulse, that were distinct from other sources of variability observed in our study. In total, this work illustrates the value of combining deep molecular and digital monitoring of human health. A record of this paper's transparent peer review process is included in the supplemental information.
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| 10. |
- Willing, Ben P., et al.
(författare)
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A Pyrosequencing Study in Twins Shows That Gastrointestinal Microbial Profiles Vary With Inflammatory Bowel Disease Phenotypes
- 2010
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Ingår i: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 139:6, s. 1844-U105
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND & AIMS: The composition of the gastrointestinal microbiota is thought to have an important role in the etiology of inflammatory bowel diseases (IBDs) such as Crohn's disease (CD) and ulcerative colitis (UC). Interindividual variation and an inability to detect less abundant bacteria have made it difficult to correlate specific bacteria with disease. METHODS: We used 454 pyrotag sequencing to determine the compositions of microbial communities in feces samples collected from a cohort of 40 twin pairs who were concordant or discordant for CD or UC, and in mucosal samples from a subset of the cohort. The cohort primarily comprised patients who were in remission, but also some with active disease. RESULTS: The profiles of the microbial community differed with disease phenotypes; relative amounts of bacterial populations correlated with IBD phenotypes. The microbial compositions of individuals with CD differed from those of healthy individuals, but were similar between healthy individuals and individuals with UC. Profiles from individuals with CD that predominantly involved the ileum differed from those with CD that predominantly involved the colon; several bacterial populations increased or decreased with disease type. Changes specific to patients with ileal CD included the disappearance of core bacteria, such as Faecalibacterium and Roseburia, and increased amounts of Enterobacteriaceae and Ruminococcus gnavus. CONCLUSIONS: Bacterial populations differ in abundance among individuals with different phenotypes of CD. Specific species of bacteria are associated with ileal CD; further studies should investigate their role in pathogenesis.
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