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Translational Psychiatry Jan 2019At present, the pathophysiology of autism spectrum disorder (ASD) remains unclear. Increasing evidence suggested that gut microbiota plays a critical role in...
At present, the pathophysiology of autism spectrum disorder (ASD) remains unclear. Increasing evidence suggested that gut microbiota plays a critical role in gastrointestinal symptoms and behavioral impairment in ASD patients. The primary aim of this systematic review is to investigate potential evidence for the characteristic dysbiosis of gut microbiota in ASD patients compared with healthy controls (HCs). The MEDLINE, EMBASE, Web of Science and Scopus were systematically searched before March 2018. Human studies that compared the composition of gut microbiota in ASD patients and HCs using culture-independent techniques were included. Independent data extraction and quality assessment of studies were conducted according to PRISMA statement and Newcastle-Ottawa Scale. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was used to infer biological functional changes of the shifted microbiota with the available data in four studies. Sixteen studies with a total sample size of 381 ASD patients and 283 HCs were included in this systematic review. The quality of the studies was evaluated as medium to high. The overall changing of gut bacterial community in terms of β-diversity was consistently observed in ASD patients compared with HCs. Furthermore, Bifidobacterium, Blautia, Dialister, Prevotella, Veillonella, and Turicibacter were consistently decreased, while Lactobacillus, Bacteroides, Desulfovibrio, and Clostridium were increased in patients with ASD relative to HCs in certain studies. This systematic review demonstrated significant alterations of gut microbiota in ASD patients compared with HCs, strengthen the evidence that dysbiosis of gut microbiota may correlate with behavioral abnormality in ASD patients. However, results of inconsistent changing also existed and further big-sampled well-designed studies are needed. Generally, as a potential mediator of risk factors, the gut microbiota could be a novel target for ASD patients in the future.
Topics: Animals; Autism Spectrum Disorder; Dysbiosis; Gastrointestinal Microbiome; Humans
PubMed: 30696816
DOI: 10.1038/s41398-019-0389-6 -
Gut Microbes 2023Growth failure is among the most prevalent and devastating consequences of prematurity. Up to half of all extremely preterm neonates struggle to grow despite modern...
Growth failure is among the most prevalent and devastating consequences of prematurity. Up to half of all extremely preterm neonates struggle to grow despite modern nutrition practices. Although elegant preclinical models suggest causal roles for the gut microbiome, these insights have not yet translated into biomarkers that identify at-risk neonates or therapies that prevent or treat growth failure. This systematic review aims to identify features of the neonatal gut microbiota that are positively or negatively associated with early postnatal growth. We identified 860 articles, of which 14 were eligible for inclusion. No two studies used the same definitions of growth, ages at stool collection, and statistical methods linking microbiota to metadata. In all, 58 different taxa were associated with growth, with little consensus among studies. Two or more studies reported positive associations with Enterobacteriaceae, , , , and , and negative associations with , and . was positively associated with growth in five studies and negatively associated with growth in three studies. To gain insight into how the various definitions of growth could impact results, we performed an exploratory secondary analysis of 245 longitudinally sampled preterm infant stools, linking microbiota composition to multiple clinically relevant definitions of neonatal growth. Within this cohort, every definition of growth was associated with a different combination of microbiota features. Together, these results suggest that the lack of consensus in defining neonatal growth may limit our capacity to detect consistent, meaningful clinical associations that could be leveraged into improved care for preterm neonates.
Topics: Infant; Infant, Newborn; Humans; Infant, Premature; Gastrointestinal Microbiome; Feces; Microbiota; Enterobacteriaceae
PubMed: 36927287
DOI: 10.1080/19490976.2023.2190301 -
Advances in Nutrition (Bethesda, Md.) Jun 2024Microbiota in early life is closely associated with the health of infants, especially premature ones. Probiotics are important drivers of gut microbiota development in... (Meta-Analysis)
Meta-Analysis Review
Microbiota in early life is closely associated with the health of infants, especially premature ones. Probiotics are important drivers of gut microbiota development in preterm infants; however, there is no consensus regarding the characteristics of specific microbiota in preterm infants receiving probiotics. In this study, we performed a meta-analysis of 5 microbiome data sets (1816 stool samples from 706 preterm infants) to compare the gut microbiota of preterm infants exposed to probiotics with that of preterm infants not exposed to probiotics across populations. Despite study-specific variations, we found consistent differences in gut microbial composition and predicted functional pathways between the control and probiotic groups across different cohorts of preterm infants. The enrichment of Acinetobacter, Bifidobacterium, and Lactobacillus spp and the depletion of the potentially pathogenic bacteria Finegoldia, Veillonella, and Klebsiella spp. were the most consistent changes in the gut microbiota of preterm infants supplemented with probiotics. Probiotics drove microbiome transition into multiple preterm gut community types, and notably, preterm gut community type 3 had the highest α-diversity, with enrichment of Bifidobacterium and Bacteroides spp. At the functional level, the major predicted microbial pathways involved in peptidoglycan biosynthesis consistently increased in preterm infants supplemented with probiotics; in contrast, the crucial pathways associated with heme biosynthesis consistently decreased. Interestingly, Bifidobacterium sp. rather than Lactobacillus sp. gradually became dominant in gut microbiota of preterm infants using mixed probiotics, although both probiotic strains were administered at the same dosage. Taken together, our meta-analysis suggests that probiotics contribute to reshaping the microbial ecosystem of preterm infants at both the taxonomic and functional levels of the bacterial community. More standardized and relevant studies may contribute to better understanding the crosstalk among probiotics, the gut microbiota, and subsequent disease risk, which could help to give timely nutritional feeding guidance to preterm infants. This systematic review and meta-analysis was registered at PROSPERO (https://www.crd.york.ac.uk/PROSPERO/) as CRD42023447901.
Topics: Humans; Gastrointestinal Microbiome; Probiotics; Infant, Premature; Infant, Newborn; Bifidobacterium; Feces; Bacteria; Lactobacillus; Female
PubMed: 38908894
DOI: 10.1016/j.advnut.2024.100233 -
Journal of Oral Microbiology 2024Nitrate (NO) has been suggested as a prebiotic for oral health. Evidence indicates dietary nitrate and nitrate supplements can increase the proportion of bacterial... (Review)
Review
BACKGROUND
Nitrate (NO) has been suggested as a prebiotic for oral health. Evidence indicates dietary nitrate and nitrate supplements can increase the proportion of bacterial genera associated with positive oral health whilst reducing bacteria implicated in oral disease(s). In contrast, chlorhexidine-containing mouthwashes, which are commonly used to treat oral infections, promote dysbiosis of the natural microflora and may induce antimicrobial resistance.
METHODS
A systematic review of the literature was undertaken, surrounding the effects of nitrate on the oral microbiota.
RESULTS
Overall, = 12 and studies found acute and chronic nitrate exposure increased (representatives of) health-associated and (67% and 58% of studies, respectively) whilst reducing periodontal disease-associated (33%). Additionally, caries-associated and decreased (25% for both genera). Nitrate also altered oral microbiome metabolism, causing an increase in pH levels ( = 5), which is beneficial to limit caries development. Secondary findings highlighted the benefits of nitrate for systemic health ( = 5).
CONCLUSIONS
More clinical trials are required to confirm the impact of nitrate on oral communities. However, these findings support the hypothesis that nitrate could be used as an oral health prebiotic. Future studies should investigate whether chlorhexidine-containing mouthwashes could be replaced or complemented by a nitrate-rich diet or nitrate supplementation.
PubMed: 38420038
DOI: 10.1080/20002297.2024.2322228 -
Microorganisms Aug 2022Our systematic review aimed to evaluate the effect of periodontal interventions on the diversity and composition of periodontal microbiota assessed by high throughput...
Our systematic review aimed to evaluate the effect of periodontal interventions on the diversity and composition of periodontal microbiota assessed by high throughput sequencing (HTS) metagenomics analysis. An electronic search was conducted from database inception to November 2021. All clinical trials that evaluated the effect of periodontal interventions on the gingival microbiota through HTS were selected. The measures of alpha diversity, richness, Shannon diversity index, and the Chao1 index, were used as the primary outcome, whereas relative abundances of bacterial genera were considered as the secondary outcome. Overall, 24 studies were eligible for the systematic review, of which 13 studies were included in the meta-analysis. Periodontal intervention for the test group decreased Shannon diversity, richness, and Chao1 index (alpha diversity), as observed from baseline to post-treatment. The most common genera that increased after periodontal therapy were , , , , and , whilst , , , and decreased after periodontal therapy. Periodontal interventions may decrease the bacterial diversity and richness and alter the composition of oral microbiota in the short term. Periodontal microbiota signatures could potentially be used for the assessment of periodontal disease development, progression, and success of the intervention.
PubMed: 36014000
DOI: 10.3390/microorganisms10081582 -
Alimentary Pharmacology & Therapeutics Mar 2020Proton pump inhibitors (PPI) are widely used to treat acid-related disorders of the upper gastrointestinal tract. However, large observational studies have raised...
BACKGROUND
Proton pump inhibitors (PPI) are widely used to treat acid-related disorders of the upper gastrointestinal tract. However, large observational studies have raised concerns about PPI-associated adverse events. In recent years, data from next-generation sequencing studies suggested that PPIs affect the composition of the intestinal microbiota, while a balanced gut microbiome is essential for maintaining health.
AIM
To review the available evidence from next-generation sequencing studies on the effect of PPIs on the intestinal microbiome and to discuss possible implications of PPI-induced dysbiosis in health and disease.
METHODS
A systematic review was conducted following the recommendations of the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement. A PubMed query yielded 197 results. 19 publications met the prespecified eligibility criteria.
RESULTS
Twelve observational study cohorts with 708 PPI users and 11 interventional cohorts with 180 PPI users were included in the review. In most studies, PPI treatment did not affect microbiological richness and diversity, but was associated with distinct taxonomic alterations: In the upper gastrointestinal tract, PPI users showed overgrowth of orally derived bacteria, mostly Streptococcaceae (findings based on six independent cohorts with 126 PPI users). In faecal samples, PPIs increased multiple taxa from the orders Bacillales (eg, Staphylococcaceae), Lactobacillales (eg, Enterococcaceae, Lactobacillaceae, Streptococcaceae) and Actinomycetales (eg, Actinomycetaceae, Micrococcaceae), the families Pasteurellaceae and Enterobacteriaceae and the genus Veillonella. Taxa decreased by PPIs include Bifidobacteriaceae, Ruminococcaceae, Lachnospiraceae and Mollicutes (findings in faecal samples based on 19 independent cohorts with 790 PPI users).
CONCLUSION
PPI use is associated with moderate alterations to upper and distal gut microbiota. The available data suggest that PPI-induced hypochlorhydria facilitates colonization of more distal parts of the digestive tract by upper gastrointestinal microbiota.
Topics: Bacteria; Cohort Studies; DNA, Bacterial; Dysbiosis; Feces; Gastrointestinal Microbiome; Gastrointestinal Tract; High-Throughput Nucleotide Sequencing; Humans; Observational Studies as Topic; Proton Pump Inhibitors; Sequence Analysis, DNA
PubMed: 31990420
DOI: 10.1111/apt.15604 -
Zhonghua Xin Xue Guan Bing Za Zhi Oct 2021To analyze the changes on gut microbiota and metabolic products in patients with chronic heart failure. By searching the Pubmed, EMBASE, Cochrane Library, and CNKI,...
To analyze the changes on gut microbiota and metabolic products in patients with chronic heart failure. By searching the Pubmed, EMBASE, Cochrane Library, and CNKI, Wanfang, and CMB databases from the day of built up to December 2019, we screened related literature exploring the intestinal flora of chronic heart failure patients, and systematic review was performed to study changes in intestinal flora composition, function, and metabolites among chronic heart failure patients. A total of 10 articles were included to study the gut microbiota of patients with chronic heart failure in this analysis. The systematic review showed significant changes in β-diversity in patients with heart failure. The abundance of faecalibacterium, blautia, bacteroides, prevotella and anaerostipes was decreased, while the abundance of streptococcus, escherichia/shigella, veillonella, and enterobacte was increased. The increased microbial gene function in patients with heart failure included tryptophan metabolism, lipid metabolism, LPS synthesis,and so on, especially, bacterial genes related to trimethylamine oxide production increased significantly, while genes related to key enzymes producing the beneficial metabolite butyrate decreased significantly, and harmful metabolite trimethylamine oxide levels increased in chronic heart failure patients. There are significant changes in the structure, function and metabolites of intestinal flora in patients with chronic heart failure.
Topics: Chronic Disease; Gastrointestinal Microbiome; Heart Failure; Humans
PubMed: 34674439
DOI: 10.3760/cma.j.cn112148-20210831-00754 -
Special Care in Dentistry : Official... 2023To evaluate the prevalence and proportions of bacteria resistant to oral antiseptics used in hospitalized patients.
AIMS
To evaluate the prevalence and proportions of bacteria resistant to oral antiseptics used in hospitalized patients.
METHODS AND RESULTS
A review of randomized clinical trials (RCTs) was led by implementing the PRISMA extension for scoping reviews including various databases. MeSH terms and keywords were used to assess only RCTs with antiseptic-resistant outcomes. Fourth RCTs met the selection criteria. These trials studied 399 hospitalized patients for respiratory infections or cardiovascular disease. Methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii were predominant pathogens in the chlorhexidine group. It was found that Veillonella parvula and Campylobacter gracilis (57% of the isolates) had resistance to triclosan, while 67% of Pseudomonas, Acinetobacter, and Enterobacter species presented resistance to chlorhexidine. However, an increase in minimal inhibitory concentrations of triclosan or chlorhexidine during the follow-up period was not observed. Moreover, chlorhexidine reduced the amount of S. aureus in dental plaque and the oropharyngeal colonization by aerobic microorganisms; nonetheless, it was unsatisfactory to decrease the occurrence of respiratory infections. No adverse events were reported.
CONCLUSIONS
Resistance of V. parvula and C. gracilis to triclosan, and Pseudomonas, Acinetobacter, and Enterobacter species to chlorhexidine were perceived. However, these resistances did not increase during the follow-up period.
PubMed: 36181674
DOI: 10.1111/scd.12781 -
Brazilian Oral Research 2024This review aimed to determine the prevalence of species of yellow, purple and green microbial complexes in root canals (RC) and periodontal pockets (PP) of teeth with...
This review aimed to determine the prevalence of species of yellow, purple and green microbial complexes in root canals (RC) and periodontal pockets (PP) of teeth with endodontic-periodontal lesions. For this purpose, two reviewers searched the literature up to January 2022. Studies reporting the prevalence of species of the yellow, purple and green microbial complexes in teeth diagnosed with endodontic-periodontal lesions were included. The risk of bias of the included studies was assessed using the 14 criteria from the NIH Quality Assessment Tool. Of 1,611 references identified in the initial search, only four studies were eligible and included in the qualitative analysis. The profile and prevalence rates of bacterial species in RC and PP varied among the included studies: levels of Agregatibacter actinomycetemcomitans (12% RC, 58% PP), Capnocytophaga granulosa (10% RC, 35% PP), Capnocytophaga sputigena (15-70% RC, 0-30% PP), Streptococcus mitis (30% RC, 35% PP), Streptococcus sanguinis (30% RC, 35% PP), and Veillonella parvula (70% RC, 50% PP) were identified. The high methodological heterogeneity prevented grouping and quantitative analysis of data. The risk of bias was considered 'moderate' for all studies. The included studies identified the presence of seven bacterial species belonging to the yellow, purple, and green microbial complexes in RC and PP, but with different prevalence rates. Future clinical studies are encouraged to investigate the presence and role of these species in the occurrence and development of endodontic-periodontal lesions.
Topics: Humans; Dental Pulp Cavity; Prevalence; Periodontal Pocket
PubMed: 38922208
DOI: 10.1590/1807-3107bor-2024.vol38.0048