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1.
Microb Genom ; 10(5)2024 May.
Article in English | MEDLINE | ID: mdl-38814176

ABSTRACT

Aeromonas caviae is an emerging human enteric pathogen. However, the genomic features and virulence genes of A. caviae strains from human gastroenteritis and other sources have not been fully elucidated. Here, we conducted a genomic analysis of 565 global A. caviae strains isolated from different sources, including 261 strains isolated from faecal samples of gastroenteritis patients, of which 18 genomes were sequenced in this study. The presence of bacterial virulence genes and secretion systems in A. caviae strains from different sources was compared, and the phylogenetic relationship of A. caviae strains was assessed based on the core genome. The complete genome of A. caviae strain A20-9 isolated from a gastroenteritis patient was obtained in this study, from which 300 putative virulence factors and a T4SS-encoding plasmid, pAC, were identified. Genes encoding T4SS were also identified in a novel genomic island, ACI-1, from other T4SS-positive strains. The prevalence of T4SS was significantly lower in A. caviae strains from gastroenteritis patients than in environmental strains (3 %, P<0.0001 vs 14 %, P<0.01). Conversely, the prevalence of T6SS was significantly higher in A. caviae strains isolated from gastroenteritis patients than in environmental strains (25 %, P<0.05 vs 13  %, P<0.01). Four phylogenetic clusters were formed based on the core genome of 565 A. caviae strains, and strains carrying T6SS often showed close phylogenetic relationships. T3SS, aerolysin and thermostable cytotonic enterotoxin were absent in all 565 A. caviae strains. Our findings provide novel information on the genomic features of A. caviae and suggest that T6SS may play a role in A. caviae-induced human gastroenteritis.


Subject(s)
Aeromonas caviae , Gastroenteritis , Genome, Bacterial , Phylogeny , Virulence Factors , Gastroenteritis/microbiology , Humans , Aeromonas caviae/genetics , Aeromonas caviae/classification , Virulence Factors/genetics , Type VI Secretion Systems/genetics , Feces/microbiology , Gram-Negative Bacterial Infections/microbiology , Genomic Islands , Plasmids/genetics
2.
Microbiol Spectr ; : e0108823, 2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37732778

ABSTRACT

Aeromonas species are emerging human enteric pathogens. This study examines the isolation of Aeromonas and other enteric bacterial pathogens from patients with and without inflammatory bowel disease (IBD). This study also investigates the intestinal epithelial pathogenic mechanisms of Aeromonas veronii. The isolation rates of seven enteric bacterial pathogens from 2,279 patients with IBD and 373,276 non-IBD patients were compared. An A. veronii strain (AS1) isolated from intestinal biopsies of a patient with IBD was used for pathogenic mechanism investigation, and Escherichia coli K12 was used as a bacterial control. HT-29 cells were used as a model of human intestinal epithelium. A significantly higher isolation of Aeromonas species was found in patients with IBD as compared to non-IBD patients (P = 0.0001, odds ratio = 2.11). A. veronii upregulated 177 inflammatory genes and downregulated 52 protein-coding genes affecting chromatin assembly, multiple small nuclear RNAs, multiple nucleolar RNAs, and 55 cytoplasmic tRNAs in HT-29 cells. These downregulation effects were unique to A. veronii and not observed in HT-29 cells infected with E. coli K12. A. veronii induced intestinal epithelial apoptosis involving the intrinsic pathway. A. veronii caused epithelial microvilli shortening and damage and epithelial production of IL-8. In conclusion, this study for the first time reports the association between IBD and Aeromonas enteric infection detected by bacterial cultivation. This study also reports that A. veronii damages intestinal epithelial cells via multiple mechanisms, of which the downregulating cytoplasmic tRNA, small nuclear RNA, and small nucleolar RNA are novel bacterial pathogenic mechanisms. IMPORTANCE This study for the first time reports the association between inflammatory bowel disease (IBD) and Aeromonas enteric infection detected by bacterial pathogen cultivation, highlighting the need of clinical and public health attention. The finding that patients with IBD are more susceptible to Aeromonas enteric infection suggests that detection of Aeromonas enteric infection should be routinely performed for the diagnosis and treatment of IBD. This study also reports novel bacterial pathogenic mechanisms employed by Aeromonas veronii. Through comparative transcriptomic analysis and other techniques, this study revealed the pathogenic mechanisms by which A. veronii causes damage to intestinal epithelial cells. Among the various pathogenic mechanisms identified, the downregulating tRNA, small nuclear and nucleolar RNAs in human intestinal epithelial cells are novel bacterial pathogenic mechanisms.

3.
Front Cell Infect Microbiol ; 12: 979055, 2022.
Article in English | MEDLINE | ID: mdl-36519137

ABSTRACT

Campylobacteriosis is a gastroenteritis caused by pathogenic Campylobacter species and an important topic in public health. Here we review the global epidemiology of campylobacteriosis in the last eight years between 2014-2021, providing comprehensive and updated information on the reported incidence and outbreaks of Campylobacter infections. The government public health website of each of the 195 countries and publications from 2014 to September 2022 in public databases were searched. The reported incidence of campylobacteriosis in pre-COVID-19 years was compared to that during the COVID-19 pandemic in countries where data were available. Czech Republic had the highest reported incidence of campylobacteriosis worldwide (215 per 100,000 in 2019), followed by Australia (146.8 per 100,000 in 2016) and New Zealand (126.1 per 100,000 in 2019). Campylobacter was one of the most common human enteric pathogens in both developed and developing countries. About 90% of cases of campylobacteriosis were caused by Campylobacter jejuni, whereas less than 10% of cases were caused by Campylobacter coli. Other Campylobacter species were also isolated. The reported incidence and case numbers of campylobacteriosis in developed nations have remained steadily high prior to the COVID-19 pandemic, whilst some countries reported an increasing trend such as France and Japan. While outbreaks were more frequently reported in some countries, Campylobacter infections were mainly sporadic cases in most of the developed countries. Campylobacter infection was more common in summer in some but not all countries. Campylobacter infection was more common in males than females. The COVID-19 pandemic has reduced the reported incidence of campylobacteriosis in most countries where 2020 epidemiology data were available. In conclusion, Campylobacter infection remains a global health concern. Increased research and improved strategies are needed for prevention and reduction of Campylobacter infection.


Subject(s)
COVID-19 , Campylobacter Infections , Campylobacter jejuni , Campylobacter , Gastroenteritis , Male , Female , Humans , Campylobacter Infections/epidemiology , Pandemics , COVID-19/epidemiology
4.
Microb Genom ; 8(9)2022 09.
Article in English | MEDLINE | ID: mdl-36107142

ABSTRACT

Little is known of the relationships among paediatric upper gastrointestinal microbiotas, and the impact of medication use and disease on their diversity. Here, we investigated the diversity of three microbiotas in the upper gastrointestinal tract of paediatric patients in relation to each other and to host factors. Oral, oesophageal and gastric microbiotas from a prospective paediatric cohort (n=54) were profiled using the 16S rRNA gene and ITS2 amplicon sequencing. 16S rRNA gene amplicon sequencing of oesophageal biopsies from a retrospective paediatric cohort (n=96) and shotgun metagenomics data from oesophageal brushings (n=88) were employed for genomic signature validation. Bacterial diversity and composition showed substantial differences across oral, oesophageal and gastric fluid samples that were not replicated for fungi, and the presence of reflux led to increased homogeneity in the bacterial component of these three microbiotas. The oral and oesophageal microbiotas were associated with age, sex, history of oesophageal atresia and presence of oesophageal metaplasia, with the latter characterized by Prevotella enrichment. Proton pump inhibitor use was associated with increased oral bacterial richness in the gastric fluid, and this correlated with increased levels of gastric pro-inflammatory cytokines. Profiling of oesophageal biopsies from a retrospective paediatric cohort confirmed an increased Prevotella prevalence in samples with metaplasia. Analysis of metagenome-derived oesophageal Prevotella melaninogenica genomes identified strain-specific features that were significantly increased in prevalence in samples with metaplasia. Prevotella enrichment is a signature associated with paediatric oesophageal metaplasia, and proton pump inhibitor use substantially alters the paediatric gastric microenvironment.


Subject(s)
Esophagitis, Peptic , Gastrointestinal Microbiome , Microbiota , Upper Gastrointestinal Tract , Bacteria/genetics , Child , Cytokines , Esophagitis, Peptic/drug therapy , Humans , Metaplasia/drug therapy , Microbiota/genetics , Prospective Studies , Proton Pump Inhibitors/therapeutic use , RNA, Ribosomal, 16S/genetics , Retrospective Studies
5.
BMC Genomics ; 23(1): 166, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35227192

ABSTRACT

BACKGROUND: Aeromonas veronii is a Gram-negative rod-shaped motile bacterium that inhabits mainly freshwater environments. A. veronii is a pathogen of aquatic animals, causing diseases in fish. A. veronii is also an emerging human enteric pathogen, causing mainly gastroenteritis with various severities and also often being detected in patients with inflammatory bowel disease. Currently, limited information is available on the genomic information of A. veronii strains that cause human gastrointestinal diseases. Here we sequenced, assembled and analysed 25 genomes (one complete genome and 24 draft genomes) of A. veronii strains isolated from patients with gastrointestinal diseases using combine sequencing technologies from Illumina and Oxford Nanopore. We also conducted comparative analysis of genomes of 168 global A. veronii strains isolated from different sources. RESULTS: We found that most of the A. veronii strains isolated from patients with gastrointestinal diseases were closely related to each other, and the remaining were closely related to strains from other sources. Nearly 300 putative virulence factors were identified. Aerolysin, microbial collagenase and multiple hemolysins were present in all strains isolated from patients with gastrointestinal diseases. Type III Secretory System (T3SS) in A. veronii was in AVI-1 genomic island identified in this study, most likely acquired via horizontal transfer from other Aeromonas species. T3SS was significantly less present in A. veronii strains isolated from patients with gastrointestinal diseases as compared to strains isolated from fish and domestic animals. CONCLUSIONS: This study provides novel information on source of infection and virulence of A. veronii in human gastrointestinal diseases.


Subject(s)
Aeromonas veronii , Gastrointestinal Diseases , Genome, Bacterial , Gram-Negative Bacterial Infections , Aeromonas veronii/genetics , Aeromonas veronii/pathogenicity , Animals , Fish Diseases/microbiology , Gastrointestinal Diseases/genetics , Gastrointestinal Diseases/microbiology , Gram-Negative Bacterial Infections/genetics , Humans , Virulence/genetics
6.
Front Microbiol ; 13: 801892, 2022.
Article in English | MEDLINE | ID: mdl-35283816

ABSTRACT

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract with unknown etiology. The pathogenesis of IBD results from immune responses to microbes in the gastrointestinal tract. Various bacterial species that are associated with human IBD have been identified. However, the microbes that trigger the development of human IBD are still not clear. Here we review bacterial species that are associated with human IBD and their pathogenic mechanisms to provide an updated broad understanding of this research field. IBD is an inflammatory syndrome rather than a single disease. We propose a three-stage pathogenesis model to illustrate the roles of different IBD-associated bacterial species and gut commensal bacteria in the development of human IBD. Finally, we recommend microbe-targeted therapeutic strategies based on the three-stage pathogenesis model.

7.
J Oral Microbiol ; 13(1): 1978732, 2021.
Article in English | MEDLINE | ID: mdl-34552702

ABSTRACT

Introduction: Campylobacter concisus is an oral bacterium that is associated with inflammatory bowel disease (IBD) and Barrett's esophagus (BE). Programmed cell death ligand-1 (PD-L1) is an immune checkpoint protein that is used by tumor cells for immune evasion and has increased expression in patients with IBD and BE. We examined whether C. concisus upregulates PD-L1 expression in intestinal and esophageal epithelial cells. Methods: Human intestinal epithelial HT-29 cells and esophageal epithelial FLO-1 cells with and without interferon (IFN)-γ sensitization were incubated with C. concisus strains. The level of PD-L1 mRNA was quantified using quantitative real-time PCR. Cytokines were measured using Enzyme-Linked Immunosorbent Assay (ELISA). Apoptosis of HT-29 and FLO-1 cells were measured using caspase 3/7 assay. Results: We found that intestinal epithelial cells with IFN-γ sensitization incubated with C. concisus significantly upregulated PD-L1 expression and significantly increased the production of interleukin (IL)-8. Whereas, PD-L1 expression was significantly inhibited in IFN-γ sensitized FLO-1 cells incubated with C. concisus strains. Furthermore, FLO-1 cells with and without IFN-γ sensitization incubated with C. concisus strains both had significantly higher levels of cell death. Conclusion: C. concisushas the potential to cause damage to both intestinal and esophageal epithelial cells, however, with different pathogenic effects.

8.
Genome Med ; 13(1): 133, 2021 08 19.
Article in English | MEDLINE | ID: mdl-34412659

ABSTRACT

BACKGROUND: The enrichment of Gram-negative bacteria of oral origin in the esophageal microbiome has been associated with the development of metaplasia. However, to date, no study has comprehensively assessed the relationships between the esophageal microbiome and the host. METHODS: Here, we examine the esophageal microenvironment in gastro-esophageal reflux disease and metaplasia using multi-omics strategies targeting the microbiome and host transcriptome, followed by targeted culture, comparative genomics, and host-microbial interaction studies of bacterial signatures of interest. RESULTS: Profiling of the host transcriptome from esophageal mucosal biopsies revealed profound changes during metaplasia. Importantly, five biomarkers showed consistent longitudinal changes with disease progression from reflux disease to metaplasia. We showed for the first time that the esophageal microbiome is distinct from the salivary microbiome and the enrichment of Campylobacter species as a consistent signature in disease across two independent cohorts. Shape fitting and matrix correlation identified associations between the microbiome and host transcriptome profiles, with a novel co-exclusion relationship found between Campylobacter and napsin B aspartic peptidase. Targeted culture of Campylobacter species from the same cohort revealed a subset of isolates to have a higher capacity to survive within primary human macrophages. Comparative genomic analyses showed these isolates could be differentiated by specific genomic features, one of which was validated to be associated with intracellular fitness. Screening for these Campylobacter strain-specific signatures in shotgun metagenomics data from another cohort showed an increase in prevalence with disease progression. Comparative transcriptomic analyses of primary esophageal epithelial cells exposed to the Campylobacter isolates revealed expression changes within those infected with strains with high intracellular fitness that could explain the increased likelihood of disease progression. CONCLUSIONS: We provide a comprehensive assessment of the esophageal microenvironment, identifying bacterial strain-specific signatures with high relevance to progression of metaplasia.


Subject(s)
Barrett Esophagus/etiology , Barrett Esophagus/metabolism , Biomarkers , Cellular Microenvironment , Disease Susceptibility , Esophagus/metabolism , Adult , Barrett Esophagus/pathology , Cellular Microenvironment/genetics , Epithelial Cells/metabolism , Epithelial Cells/pathology , Esophagus/microbiology , Esophagus/pathology , Female , Gastroesophageal Reflux/complications , Gastroesophageal Reflux/etiology , Gene Expression Profiling , Gram-Negative Bacterial Infections/complications , Gram-Negative Bacterial Infections/microbiology , Host-Pathogen Interactions/genetics , Humans , Macrophages/immunology , Macrophages/metabolism , Male , Mast Cells/immunology , Mast Cells/metabolism , Metaplasia , Microbiota , Middle Aged , Models, Biological , RNA, Ribosomal, 16S
9.
Microorganisms ; 9(7)2021 Jul 03.
Article in English | MEDLINE | ID: mdl-34361876

ABSTRACT

Aeromonas species are emerging human enteric pathogens. However, systematic analysis of Aeromonas species infection in human gastroenteritis in comparison with other enteric bacterial pathogens in the Australian population is lacking. Here we analysed the isolation of Aeromonas species and other bacterial pathogens in five consecutive years (2015-2019) from 375,842 stool samples of patients with gastroenteritis in a large Australian diagnostic laboratory and identified a subset (48 isolates) of Aeromonas isolates to species level, using multilocus phylogenetic analysis. Aeromonas species were the third most common bacterial pathogens, following Campylobacter and Salmonella species. Aeromonas infection rate was significantly correlated with increasing age (p < 0.001). Aeromonas species were more often isolated in warm seasons and in males than females (p < 0.001). Five Aeromonas species were identified. Most of the infections were from three species, namely Aeromonas veronii (52%), Aeromonas caviae (27%) and Aeromonas hydrophila (12.5%). The majority of patients with Aeromonas species infection did not have a documented overseas travel history. The findings from this study support the importance of Aeromonas species in human gastroenteritis and suggest that the sources of Aeromonas infection in Australian patients should be further investigated.

10.
Diabetes Care ; 44(5): 1176-1184, 2021 05.
Article in English | MEDLINE | ID: mdl-33653821

ABSTRACT

OBJECTIVE: Insulin delivery methods, glucose-monitoring modalities, and related outcomes were examined in a large, international, diverse cohort of children and adolescents with type 1 diabetes from the Better Control in Pediatric and Adolescent Diabetes: Working to Create Centers of Reference (SWEET) -Registry. RESEARCH DESIGN AND METHODS: Participants with type 1 diabetes of ≥1 year, aged ≤18 years, and who had documented pump or sensor usage during the period August 2017-July 2019 were stratified into four categories: injections-no sensor (referent); injections + sensor; pump-no sensor; and pump + sensor. HbA1c and proportion of patients with diabetic ketoacidosis (DKA) or severe hypoglycemia (SH) were analyzed; linear and logistic regression models adjusted for demographics, region, and gross domestic product per capita were applied. RESULTS: Data of 25,654 participants were analyzed. The proportions of participants (adjusted HbA1c data) by study group were as follows: injections-no sensor group, 37.44% (8.72; 95% CI 8.68-8.75); injections + sensor group, 14.98% (8.30; 95% CI 8.25-8.35); pump-no sensor group, 17.22% (8.07; 95% CI 8.03-8.12); and pump + sensor group, 30.35% (7.81; 95% CI 7.77-7.84). HbA1c was lower in all categories of participants who used a pump and/or sensor compared with the injections-no sensor treatment method (P < 0.001). The proportion of DKA episodes was lower in participants in the pump + sensor (1.98%; 95% CI 1.64-2.48; P < 0.001) and the pump-no sensor (2.02%; 95% CI 1.64-2.48; P < 0.05) groups when compared with those in the injections-no sensor group (2.91%; 95% CI 2.59-3.31). The proportion of participants experiencing SH was lower in pump-no sensor group (1.10%; 95% CI 0.85-1.43; P < 0.001) but higher in the injections + sensor group (4.25%; 95% CI 3.65-4.95; P < 0.001) compared with the injections-no sensor group (2.35%; 95% CI 2.04-2.71). CONCLUSIONS: Lower HbA1c and fewer DKA episodes were observed in participants using either a pump or continuous glucose monitoring (CGM) or both. Pump use was associated with a lower rate of SH. Across SWEET centers, use of pumps and CGM is increasing. The concomitant use of pump and CGM was associated with an additive benefit.


Subject(s)
Diabetes Mellitus, Type 1 , Adolescent , Blood Glucose , Blood Glucose Self-Monitoring , Child , Diabetes Mellitus, Type 1/drug therapy , Glycated Hemoglobin/analysis , Humans , Hypoglycemic Agents/adverse effects , Insulin/adverse effects , Insulin Infusion Systems , Registries
11.
Microb Genom ; 6(11)2020 11.
Article in English | MEDLINE | ID: mdl-33111662

ABSTRACT

Campylobacter concisus is an emerging enteric pathogen that is associated with several gastrointestinal diseases, such as inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC). Currently, only three complete C. concisus genomes are available and more complete C. concisus genomes are needed in order to better understand the genomic features and pathogenicity of this emerging pathogen. DNA extracted from 22 C. concisus strains were subjected to Oxford Nanopore genome sequencing. Complete genome assembly was performed using Nanopore genome data in combination with previously reported short-read Illumina data. Genome features of complete C. concisus genomes were analysed using bioinformatic tools. The enteric disease associations of C. concisus plasmids were examined using 239 C. concisus strains and confirmed using PCRs. Proteomic analysis was used to examine T6SS secreted proteins. We successfully obtained 13 complete C. concisus genomes in this study. Analysis of 16 complete C. concisus genomes (3 from public databases) identified multiple novel plasmids. pSma1 plasmid was found to be associated with severe UC. Sec-SRP, Tat and T6SS were found to be the main secretion systems in C. concisus and proteomic data showed a functional T6SS despite the lack of ClpV. T4SS was found in 25% of complete C. concisus genomes. This study also found that GS2 strains had larger genomes and higher GC content than GS1 strains and more often had plasmids. In conclusion, this study provides fundamental genomic data for understanding C. concisus plasmids, genomospecies features, evolution, secretion systems and pathogenicity.


Subject(s)
Campylobacter Infections/pathology , Campylobacter/genetics , Colitis, Ulcerative/microbiology , Plasmids/genetics , Type VI Secretion Systems/genetics , Base Composition/genetics , Campylobacter/isolation & purification , Campylobacter/metabolism , Colitis, Ulcerative/genetics , Computational Biology , Genome, Bacterial/genetics , Humans , Phylogeny , Whole Genome Sequencing
12.
Infect Immun ; 89(1)2020 12 15.
Article in English | MEDLINE | ID: mdl-33046511

ABSTRACT

Programmed cell death ligand-1 (PD-L1) is an immune checkpoint protein which is used by tumor cells for immune evasion. PD-L1 is upregulated in inflamed intestinal tissues. The intestinal tract is colonized by millions of bacteria, most of which are commensal bacterial species. We hypothesized that under inflammatory conditions, some commensal bacterial species contribute to increased PD-L1 expression in intestinal epithelium and examined this hypothesis. Human intestinal epithelial HT-29 cells with and without interferon (IFN)-γ sensitization were incubated with six strains of four enteric bacterial species. The mRNA and protein levels of PD-L1 in HT-29 cells were examined using quantitative real-time PCR and flow cytometry, respectively. The levels of interleukin (IL)-1ß, IL-18, IL-6, IL-8, and tumor necrosis factor (TNF)-α secreted by HT-29 cells were measured using enzyme-linked immunosorbent assay. Apoptosis of HT-29 cells was measured using a caspase 3/7 assay. We found that Escherichia coli K12 significantly upregulated both PD-L1 mRNA and protein in IFN-γ-sensitized HT-29 cells. E. coli K12 induced the production of IL-8 in HT-29 cells, however, IL-8 did not affect HT-29 PD-L1 expression. Inhibition of the nuclear factor-kappa B pathway significantly reduced E. coli K12-induced PD-L1 expression in HT-29 cells. The other two E. coli strains and two enteric bacterial species did not significantly affect PD-L1 expression in HT-29 cells. Enterococcus faecalis significantly inhibited PD-L1 expression due to induction of cell death. Data from this study suggest that some gut bacterial species have the potential to affect immune function under inflammatory conditions via upregulating epithelial PD-L1 expression.


Subject(s)
B7-H1 Antigen/genetics , Escherichia coli K12/physiology , Gene Expression Regulation , Interferon-gamma/metabolism , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , NF-kappa B/metabolism , Signal Transduction , B7-H1 Antigen/metabolism , Biomarkers , Cell Line , Cytokines/metabolism , Escherichia coli Infections/genetics , Escherichia coli Infections/immunology , Escherichia coli Infections/metabolism , Escherichia coli Infections/microbiology , Host-Pathogen Interactions/genetics , Host-Pathogen Interactions/immunology , Humans
13.
Gut Pathog ; 12: 13, 2020.
Article in English | MEDLINE | ID: mdl-32165925

ABSTRACT

Campylobacter concisus is an emerging enteric pathogen that is associated with inflammatory bowel disease. Previous studies demonstrated that C. concisus is non-saccharolytic and hydrogen gas (H2) is a critical factor for C. concisus growth. In order to understand the molecular basis of the non-saccharolytic and H2-dependent nature of C. concisus growth, in this study we examined the pathways involving energy metabolism and oxidative stress defence in C. concisus. Bioinformatic analysis of C. concisus genomes in comparison with the well-studied enteric pathogen Campylobacter jejuni was performed. This study found that C. concisus lacks a number of key enzymes in glycolysis, including glucokinase and phosphofructokinase, and the oxidative pentose phosphate pathway. C. concisus has an incomplete tricarboxylic acid cycle, with no identifiable succinyl-CoA synthase or fumarate hydratase. C. concisus was inferred to use fewer amino acids and have fewer candidate substrates as electron donors and acceptors compared to C. jejuni. The addition of DMSO or fumarate to media resulted in significantly increased growth of C. concisus in the presence of H2 as an electron donor, demonstrating that both can be used as electron acceptors. Catalase, an essential enzyme for oxidative stress defence in C. jejuni, and various nitrosative stress enzymes, were not found in the C. concisus genome. Overall, C. concisus is inferred to have a non-saccharolytic metabolism in which H2 is central to energy conservation, and a narrow selection of carboxylic acids and amino acids can be utilised as organic substrates. In conclusion, this study provides a molecular basis for the non-saccharolytic and hydrogen-dependent nature of C. concisus energy metabolism pathways, which provides insights into the growth requirements and pathogenicity of this species.

14.
Front Med (Lausanne) ; 7: 580803, 2020.
Article in English | MEDLINE | ID: mdl-33392214

ABSTRACT

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract mainly comprising two forms including Crohn's disease (CD) and ulcerative colitis (UC). IBD is a lifelong relapsing remitting disease and relapses occur at random patterns which are unpredictable. Fecal biomarkers have been increasingly used to assess disease activity in IBD due to their positive correlations with intestinal inflammation. Recent studies have also assessed the use of fecal biomarkers in predicting relapse and post-operative recurrence. This review provides information from global studies of using fecal calprotectin, lactoferrin and S100A12 to predict relapse in IBD. Strategies for further studies and the use of these fecal biomarkers for personalized management in IBD are also discussed.

16.
Mediators Inflamm ; 2019: 7028253, 2019.
Article in English | MEDLINE | ID: mdl-31780866

ABSTRACT

Anti-cytokine antibodies are used in treating chronic inflammatory diseases and autoimmune diseases such as inflammatory bowel disease and rheumatic diseases. Patients with these diseases often have a compromised gut barrier function, suggesting that anti-cytokine antibodies may contribute to the re-establishment of gut barrier integrity, in addition to their immunomodulatory effects. This paper reviews the effects of anti-cytokine antibodies on gut barrier function and their mechanisms.


Subject(s)
Antibodies/therapeutic use , Cytokines/antagonists & inhibitors , Cytokines/immunology , Animals , Humans , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/immunology , Rheumatic Diseases/drug therapy , Rheumatic Diseases/immunology
17.
Biochem Biophys Res Commun ; 518(1): 44-49, 2019 10 08.
Article in English | MEDLINE | ID: mdl-31400853

ABSTRACT

Campylobacter concisus is an emerging bacterial pathogen that may play a role in the development of inflammatory bowel disease and oral inflammatory conditions such as periodontal disease. To elucidate the role and pathogenic mechanisms of C. concisus in contributing to oral inflammation, this study examined the production of IL-1 family proinflammatory cytokines IL-18 and IL-1ß in oral epithelial cells induced by C. concisus strains using enzyme-linked immunosorbent assay (ELISA), Western-blot and quantitative real-time PCR. C. concisus increased the mRNA levels of IL-18 and IL-1ß in oral epithelial cells. Furthermore, a large amount of IL-18 in the supernatants of oral epithelial cells infected with C. concisus strains was detected by ELISA, and various experiments demonstrated that this positive signal was derived from C. concisus bacterium. The findings that C. concisus upregulated IL-18 and IL-1ß in oral epithelial cells from this study support a role of C. concisus in oral inflammatory diseases. Furthermore, the finding that C. concisus released a molecule that was strongly cross-reactive to anti-human IL-18 monoclonal antibodies suggests that in future studies examining cytokines induced by bacterial microbes, a bacterium control should be included.


Subject(s)
Campylobacter/physiology , Epithelial Cells/metabolism , Epithelial Cells/microbiology , Interleukin-18/genetics , Interleukin-1beta/genetics , Mouth/cytology , Cell Line , Humans , Interleukin-18/metabolism , Interleukin-1beta/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism
18.
J Pediatr ; 215: 216-222.e1, 2019 12.
Article in English | MEDLINE | ID: mdl-31345576

ABSTRACT

OBJECTIVES: To investigate in a large population the proportion of daily basal insulin dose (BD) to daily total insulin dose (TD) (BD/TD) and its association with glycated hemoglobin A1c (HbA1c), body mass index (BMI)- SDS, and treatment modality in children with type 1 diabetes. STUDY DESIGN: Cross-sectional study in subjects with type 1 diabetes, age ≤18 years, and ≥2 years of diabetes duration, registered in the international multicenter Better control in Pediatric and Adolescent diabeteS: Working to crEate CEnTers of Reference registry in March 2018. Variables included region, sex, age, diabetes duration, treatment modality (multiple daily injections [MDI] or continuous subcutaneous insulin infusion [CSII]), self-monitoring blood glucose, HbA1c, BD/TD, and BMI-SDS. BMI was converted to BMI-SDS using World Health Organization charts as reference. Hierarchic linear regression models were applied with adjustment for age, sex, and diabetes duration. RESULTS: A total of 19 687 children with type 1 diabetes (49% female, 49% CSII users) with median age 14.8 (11.5; 17.2) years and diabetes duration 6.0 (3.9; 9.0) years were included. HbA1c was 63 (55; 74) mmol/mol (7.9 [7.2; 8.9]%), and BMI-SDS 0.55 (-0.13; 1.21). Unadjusted, a lower BD/TD was associated with lower HbA1c, male sex, younger age, shorter diabetes duration, lower BMI-SDS, higher numbers of self-monitoring blood glucose and CSII (all P < .01). After adjustment for confounders, lower BD/TD was associated with lower HbA1c (P < .01) and lower BMI-SDS (P < .01) in children on CSII, but not on MDI. CONCLUSIONS: Lower BD/TD is positively associated with lower HbA1c and lower BMI-SDS in children with type 1 diabetes on CSII. It remains to be investigated in a prospective study whether reducing BD/TD insulin will improve metabolic control and normalize body weight in children with type 1 diabetes.


Subject(s)
Body Mass Index , Diabetes Mellitus, Type 1/drug therapy , Glycated Hemoglobin/analysis , Hypoglycemic Agents/administration & dosage , Insulin/administration & dosage , Adolescent , Blood Glucose Self-Monitoring , Child , Cross-Sectional Studies , Diabetes Mellitus, Type 1/blood , Dose-Response Relationship, Drug , Female , Humans , Injections, Subcutaneous , Insulin Infusion Systems , Male , Registries
19.
Front Oncol ; 9: 566, 2019.
Article in English | MEDLINE | ID: mdl-31334107

ABSTRACT

Colorectal cancer (CRC) is the third most prevalent cancer and second in terms of mortality. Emerging evidence from recent studies suggests a potential role of Fusobacterium nucleatum in the development of CRC. In this article, we review studies from different geographical regions examining the association between F. nucleatum and CRC, the detection methods and the tumorigenic mechanisms. Furthermore, we discuss the potential clinical impact of F. nucleatum in CRC and suggest future study directions.

20.
Biomark Res ; 6: 35, 2018.
Article in English | MEDLINE | ID: mdl-30555700

ABSTRACT

OPCML hypermethylation is considered a promising cancer biomarker. We examined methylation levels in the first exon of OPCML in two patient cohorts within the esophageal adenocarcinoma and gastric adenocarcinoma cascades and in a range of cell-lines using a custom PyroMark CpG assay. Methylation levels were significantly higher in esophageal tissue with histologically confirmed glandular mucosa as compared to tissue from normal esophagi or gastro-esophageal reflux disease. Higher levels of OPCML methylation were absent in the adjacent normal esophageal tissue of patients with glandular mucosa. Higher levels of methylation were confirmed in cell-lines derived from patients with adenocarcinoma, but also detected in two cell-lines with signs of dysplasia. We validated our assay by showing no differences in methylation levels in DNA extracted from blood of patients within the gastric adenocarcinoma cascade. OPCML hypermethylation is present in a subset of patients with metaplastic changes in their esophagus.

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