| 1. |
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| 2. |
- Benno, Peter, et al.
(författare)
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From IBS to DBS : The Dysbiotic Bowel Syndrome
- 2016
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Ingår i: JOURNAL OF INVESTIGATIVE MEDICINE HIGH IMPACT CASE REPORTS. - : SAGE PUBLICATIONS LTD. - 2324-7096. ; 4:2
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Tidskriftsartikel (refereegranskat)abstract
- Irritable bowel syndrome is a chronic gastrointestinal disorder characterized by abdominal pain and altered bowel habits in the absence of organic disease. We present 2 cases where diarrhea-predominant irritable bowel syndrome occurred in association with earlier intestinal infection or antibiotic treatment. Both were successfully treated with instillation of an anaerobic cultivated human intestinal microbiota. Thereafter, they were symptom free for at least 12 months. We now introduce the term dysbiotic bowel syndrome covering cases where a disturbed intestinal microbiota is assumed to be present. We recommend that restoration of the dysbiotic gut microbiota should be first-line treatment in these conditions.
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| 3. |
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| 4. |
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| 5. |
- Cheng, Liqin, et al.
(författare)
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The protective role of commensal gut microbes and their metabolites against bacterial pathogens
- 2024
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Ingår i: Gut microbes. - : Taylor & Francis. - 1949-0976 .- 1949-0984. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Multidrug-resistant microorganisms have become a major public health concern around the world. The gut microbiome is a gold mine for bioactive compounds that protect the human body from pathogens. We used a multi-omics approach that integrated whole-genome sequencing (WGS) of 74 commensal gut microbiome isolates with metabolome analysis to discover their metabolic interaction with Salmonella and other antibiotic-resistant pathogens. We evaluated differences in the functional potential of these selected isolates based on WGS annotation profiles. Furthermore, the top altered metabolites in co-culture supernatants of selected commensal gut microbiome isolates were identified including a series of dipeptides and examined for their ability to prevent the growth of various antibiotic-resistant bacteria. Our results provide compelling evidence that the gut microbiome produces metabolites, including the compound class of dipeptides that can potentially be applied for anti-infection medication, especially against antibiotic-resistant pathogens. Our established pipeline for the discovery and validation of bioactive metabolites from the gut microbiome as novel candidates for multidrug-resistant infections represents a new avenue for the discovery of antimicrobial lead structures.
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| 6. |
- Gio-Batta, Monica, et al.
(författare)
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Low Concentration of Fecal Valeric Acid at 1 Year of Age Is Linked with Eczema and Food Allergy at 13 Years of Age : Findings from a Swedish Birth Cohort
- 2022
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Ingår i: International Archives of Allergy and Immunology. - : S. Karger. - 1018-2438 .- 1423-0097. ; , s. 398-408
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Tidskriftsartikel (refereegranskat)abstract
- Background: Short-chain fatty acids (SCFAs) are abundant bacterial metabolites in the gut, with immunomodulatory properties. Hence, they may influence allergy development. Previous studies have linked fecal SCFA pattern during infancy with allergy. However, the association of SCFAs to allergic outcomes in adolescence is not well established. Here, we examined how the fecal SCFA pattern at 1 year of age related to allergy at 13 years of age.Methods: Levels of 8 SCFAs in fecal samples collected at 1 year of age from 110 children were quantified using gas chromatography. The same individuals were evaluated at 13 years of age for allergic symptoms, allergy diagnosis and allergy medication by questionnaire, and for sensitization using skin prick test against egg, milk, fish, wheat and soy, cat, dog, horse, birch, and timothy grass.Results: The concentration of fecal valeric acid at 1 year of age was inversely associated with eczema at 13 years of age (OR 0.6, 95% CI: 0.4-1.0, p = 0.049) and showed a trend for inverse association with food allergy at 13 years of age (OR 0.6, 95% CI: 0.4-1.0, p = 0.057). In a sub-group analysis of children with eczema at 1 year of age, a higher concentration of fecal valeric acid was linked with reduced risk of their eczema remaining at 13 years of age (OR 0.2, 95% CI: 0.0-1.5), although this latter analysis did not reach statistical significance (p = 0.12).Conclusions: Our findings lend further support to the notion of early childhood as a critical period when allergy may be programmed via the gut microbiota. Higher levels of fecal valeric acid may be characteristic of a protective gut microbiota and/or actively contribute to protection from eczema and food allergy.
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| 7. |
- Hanson, Lars Åke, 1934, et al.
(författare)
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Growth and nutrition: the first six months
- 2008
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Ingår i: Nestlé Nutrition workshop series. Paediatric programme. - Basel : KARGER. - 1661-6677. ; 61, s. 123-34
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Today the WHO Growth Chart Standards, based on the growth of breastfed infants, are used. These growth curves solve the problem of the deviating observations for breastfed compared to non-breastfed infants using previous growth charts. Presently it is not clear how the mother's diet, especially the fat intake, influences the growth of the offspring. Animal experiments indicate that a low intake of n-3 polyunsaturated fatty acids via the milk may have short- and long-term negative consequences. There is limited information in man. It has been suggested that the mammary glands may have phylogenetically originated from glands providing innate immunity, later developing capacities for providing nutrition. This would agree with the fact that human milk contains so many major components which do not primarily function as nutrients, but seem to protect nutrition and growth. Lactoferrin, oligosaccharides, glycoproteins, secretory IgA antibodies, alpha-lactalbumin and the antisecretory factor have such functions.
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| 8. |
- Lin, Weifeng, et al.
(författare)
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Sensitive quantification of short-chain fatty acids combined with global metabolomics in microbiome cultures
- 2023
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Ingår i: Chemical Communications. - : Royal Society of Chemistry. - 1359-7345 .- 1364-548X. ; 59:39, s. 5843-5846
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Tidskriftsartikel (refereegranskat)abstract
- The microbiome has been identified to have a key role for the physiology of their human host. One of the major impacts is the clearance of bacterial pathogens. We have now developed a chemoselective probe methodology for the absolute quantification of short-chain fatty acids at low nM concentrations, with high reproducibility and spiked isotope labelled internal standards. Immobilization to magnetic beads allows for separation from the matrix and the tagged metabolites upon bioorthogonal cleavage can be analyzed via UHPLC-MS. The major advantage of our sensitive method is the simple combination with global metabolomics analysis as only a small sample volume is required. We have applied this chemical metabolomics strategy for targeted SCFA analysis combined with global metabolomics on gut microbiome co-cultures with Salmonella and investigated the effect of antibiotic treatment.
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| 9. |
- Midtvedt, Tore, et al.
(författare)
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Increase of faecal tryptic activity relates to changes in the intestinal microbiome : analysis of Crohn's disease with a multidisciplinary platform.
- 2013
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:6, s. e66074-
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To investigate-by molecular, classical and functional methods-the microbiota in biopsies and faeces from patients with active Crohn's disease (CD) and controls.DESIGN: The microbiota in biopsies was investigated utilizing a novel molecular method and classical cultivation technology. Faecal samples were investigated by classical technology and four functional methods, reflecting alterations in short chain fatty acids pattern, conversion of cholesterol and bilirubin and inactivation of trypsin.RESULTS: By molecular methods we found more than 92% similarity in the microbiota on the biopsies from the two groups. However, 4.6% of microbes found in controls were lacking in CD patients. Furthermore, NotI representation libraries demonstrate two different clusters representing CD patients and controls, respectively. Utilizing conventional technology, Bacteroides (alt. Parabacteroides) was less frequently detected in the biopsies from CD patients than from controls. A similar reduction in the number of Bacteroides was found in faecal samples. Bacteroides is the only group of bacteria known to be able to inactivate pancreatic trypsin. Faecal tryptic activity was high in CD patients, and inversely correlated to the levels of Bacteroides.CONCLUSIONS: CD patients have compositional and functional alterations in their intestinal microbiota, in line with the global description hypothesis rather than the candidate microorganism theory. The most striking functional difference was high amount of faecal tryptic activity in CD patients, inversely correlated to the levels of Bacteroides in faeces.
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| 10. |
- Sandin, Anna, et al.
(författare)
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Faecal short chain fatty acid pattern and allergy in early childhood
- 2009
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 98:5, s. 823-827
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate whether functional changes of the gut flora over time were related to sensitization and allergic symptoms at four years of age.Methods: The levels of short chain fatty acids (SCFAs) in faecal samples at one (n = 139) and four (n = 53) years of age were related to the development of positive skin prick tests (SPT) and allergic symptoms during the first four years of life.Results: Faecal acetic (p < 0.01) and propionic (p < 0.01) acids decreased from one to four years of age, while valeric acid (p < 0.001) increased. Low levels of i-butyric (p = 0.01), i-valeric (p = 0.03) and valeric acids (p = 0.02) at one year were associated with questionnaire-reported symptoms of food allergy at four years. Positive SPTs and allergic symptoms at four years were associated with low faecal levels of i-butyric, i-valeric and valeric acids. At one year of age, infants with, as compared to without older siblings had higher median levels of valeric acid.Conclusion: A slow functional maturation of the gut microflora, as measured by faecal levels of SCFAs is associated with allergy both at one and four years. The findings lend further support to an association between allergy and the development of microbial diversity.
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| 11. |
- Tjellstrom, Bo, et al.
(författare)
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Effect of exclusive enteral nutrition on gut microflora function in children with Crohns disease
- 2012
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Ingår i: Scandinavian Journal of Gastroenterology. - : Informa Healthcare. - 0036-5521 .- 1502-7708. ; 47:12, s. 1454-1459
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Tidskriftsartikel (refereegranskat)abstract
- Objective. Exclusive enteral nutrition (EEN) is a first-line treatment in children with active Crohns disease (CD) but is seldom used in adults with active disease. The mode of action of EEN in suppressing mucosa] inflammation is not fully understood, but modulation of intestinal microflora activity is one possible explanation. The aim of this study was to investigate the effect of 6-week EEN in children with active CD, with special reference to intestinal microflora function. Materials and methods. Fecal samples from 18 children (11 boys, 7 girls; median age 13.5 years) with active CD (13 children with small bowel/colonic and 5 with perianal disease) were analyzed for short chain fatty acid (SCFA) pattern as marker of gut microflora function. The children were studied before and after EEN treatment. Results from 12 healthy teenagers were used for comparison. Results. Eleven (79%) of the children with small bowel/colonic CD responded clinically positively to EEN treatment showing decreased levels of pro-inflammatory acetic acid as well as increased concentrations of anti-inflammatory butyric acids and also of valeric acids, similar to the levels in healthy age-matched children. In children with active perianal CD, however, EEN had no positive effect on clinical status or inflammatory parameters. Conclusions. The authors present new data supporting the hypothesis that the well-documented anti-inflammatory effect of EEN in children with active small bowel/colonic CD is brought about by modulation of gut microflora activity, resulting in an anti-inflammatory SCFA pattern. By contrast, none of the children with perianal disease showed clinical or biochemical improvement after EEN treatment.
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| 12. |
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| 13. |
- Tjellström, Bo, et al.
(författare)
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Faecal short-chain fatty acid pattern in childhood coeliac disease is normalised after more than one year's gluten-free diet
- 2013
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Ingår i: Microbiological Ecology in Health and Disease. - Järfälla, Sweden : Co-Action Publishing. - 0891-060X .- 1651-2235. ; 24
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Recent work indicates that the gut microflora is altered in patients with coeliac disease (CD). Faecal short-chain fatty acids (SCFAs) are produced by the gut microflora. We have previously reported a high SCFA output in children with symptomatic and asymptomatic CD at presentation, as well as in CD children on a gluten-free diet (GFD) for less than 1 year, indicating deviant gut microfloral function. In this report, we focus on faecal SCFA production in coeliacs on GFD for more than 1 year.MATERIALS AND METHODS: Faecal samples were collected from 53 children with CD at presentation, 74 coeliac children on GFD for less than 1 year, and 25 individuals diagnosed with CD in childhood and on GFD for more than 1 year. The control group comprised 54 healthy children (HC). The faecal samples were analysed to show the SCFA pattern taken as a marker of gut microflora function. We applied a new fermentation index, reflecting the inflammatory activity of the SCFAs (amount of acetic acid minus propionic acid and n-butyric acid, together divided by the total amount of SCFAs).RESULTS: In coeliacs on GFD for more than 1 year, the individual SCFAs, total SCFA, and fermentation index did not differ significantly from the findings in controls. In contrast, the faecal SCFA level was clearly higher in coeliacs treated with GFD for less than 1 year compared to those more than 1 year.CONCLUSIONS: This is the first study on SCFA patterns in faecal samples from individuals with CD on GFD for more than 1 year. Our study indicates that the disturbed gut microflora function in children with CD at presentation and after less than 1 year of GFD, previously demonstrated by us, is normalised on GFD for more than 1 year.
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| 14. |
- Tjellström, Bo, et al.
(författare)
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Gut microflora associated characteristics in first-degree relatives of children with celiac disease
- 2007
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Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 42:10, s. 1204-1208
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Tidskriftsartikel (refereegranskat)abstract
- Objective. In celiac disease (CD), enteropathy of the small bowel results from a T-cell-mediated reaction to gluten in the diet. In addition to gluten, other environmental and genetic factors participate in the disease pathogenesis. We have recently reported the finding of a significantly different short-chain fatty acid (SCFA) profile in fecal samples from children with CD compared to healthy controls reflecting an aberrant gut microflora. The aim of the present study was to make a functional evaluation of the gut microflora status in non-celiac 1st degree relatives of children with CD. Material and methods. Fecal samples from 76 symptom-free, non-celiac, 1st degree CD relatives and from 91 aged-matched healthy controls were analyzed for fecal tryptic activity (FTA) and a number of SCFAs. Results. There was a significantly lower level of acetic acid and total SCFAs as well as a significantly increased level of i-butyric acid and FTA in relatives compared to healthy controls. Conclusions. The FTA and the SCFA profiles in fecal samples from 1st degree relatives of children with CD are different from those of healthy individuals. The implication of this observation provides insight into the pathogenesis of CD and opens up the possibility of future new diagnostic, therapeutic and prophylactic strategies. © 2007 Taylor & Francis.
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| 15. |
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| 16. |
- Tjellström, Bo, et al.
(författare)
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Screening-detected and symptomatic untreated celiac children show similar gut microflora-associated characteristics
- 2010
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Ingår i: SCANDINAVIAN JOURNAL OF GASTROENTEROLOGY. - : Informa Healthcare. - 0036-5521 .- 1502-7708. ; 45:9, s. 1059-1062
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Tidskriftsartikel (refereegranskat)abstract
- Objective. The aim of this study was to investigate the metabolic function of intestinal microflora in children with screening-detected celiac disease (CD) to see if there is an aberrant gut flora in screening-detected CD similar to symptomatic CD and contrary to healthy controls. Materials and methods. As part of a Swedish multicenter screening for CD, 912 12-year-old children were screened with serum anti-human tissue transglutaminase-IgA. Small bowel biopsy specimens from children with positive serology revealed 17 individuals with CD. The functional status of the intestinal microflora was evaluated by gas liquid chromatography of short chain fatty acids (SCFAs) in fecal samples. Our previously published findings in children with symptomatic CD and healthy controls were used as comparison. Results. The children with screening-detected CD had a similar fecal SCFA profile to children with symptomatic CD, but differed significantly from that in healthy children. Conclusions. This is the first study on SCFA patterns in fecal samples from children with screening-detected CD. The similarity of the fecal SCFA profile in screening-detected and symptomatic CD indicates common pathogenic mechanisms. This could open the way for new therapeutic or prophylactic measures based on novel biological principles.
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| 17. |
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| 18. |
- Zabarovska, Veronika, et al.
(författare)
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NotI passporting to identify species composition of complex microbial systems
- 2003
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Ingår i: Nucleic Acids Research. - Oxford, United Kingdom : Oxford University Press. - 0305-1048 .- 1362-4962. ; 31:2, s. E5-5
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Tidskriftsartikel (refereegranskat)abstract
- We describe here a new method for large-scale scanning of microbial genomes on a quantitative and qualitative basis. To achieve this aim we propose to create NotI passports: databases containing NotI tags. We demonstrated that these tags comprising 19 bp of sequence information could be successfully generated using DNA isolated from intestinal or fecal samples. Such NotI passports allow the discrimination between closely related bacterial species and even strains. This procedure for generating restriction site tagged sequences (RSTS) is called passporting and can be adapted to any other rare cutting restriction enzyme. A comparison of 1312 tags from available sequenced Escherichia coli genomes, generated with the NotI, PmeI and SbfI restriction enzymes, revealed only 219 tags that were not unique. None of these tags matched human or rodent sequences. Therefore the approach allows analysis of complex microbial mixtures such as in human gut and identification with high accuracy of a particular bacterial strain on a quantitative and qualitative basis.
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| 19. |
- Zabarovsky, Eugene R, et al.
(författare)
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Restriction site tagged (RST) microarrays : a novel technique to study the species composition of complex microbial systems
- 2003
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Ingår i: Nucleic Acids Research. - Oxford, United Kingdom : Oxford University Press. - 0305-1048 .- 1362-4962. ; 31:16, s. e95-
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Tidskriftsartikel (refereegranskat)abstract
- We have developed a new type of microarray, restriction site tagged (RST), for example NotI, microarrays. In this approach only sequences surrounding specific restriction sites (i.e. NotI linking clones) were used for generating microarrays. DNA was labeled using a new procedure, NotI representation, where only sequences surrounding NotI sites were labeled. Due to these modifications, the sensitivity of RST microarrays increases several hundred-fold compared to that of ordinary genomic microarrays. In a pilot experiment we have produced NotI microarrays from Gram-positive and Gram-negative bacteria and have shown that even closely related Escherichia coli strains can be easily discriminated using this technique. For example, two E.coli strains, K12 and R2, differ by less than 0.1% in their 16S rRNA sequences and thus the 16S rRNA sequence would not easily discriminate between these strains. However, these strains showed distinctly different hybridization patterns with NotI microarrays. The same technique can be adapted to other restriction enzymes as well. This type of microarray opens the possibility not only for studies of the normal flora of the gut but also for any problem where quantitative and qualitative analysis of microbial (or large viral) genomes is needed.
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