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Case Reports in Hepatology 2021species are commensal bacteria of the human oral, gut, and vaginal microbiota that are rarely identified as clinically relevant pathogens. Here, we describe a novel...
species are commensal bacteria of the human oral, gut, and vaginal microbiota that are rarely identified as clinically relevant pathogens. Here, we describe a novel case of bacteremia in a patient with biopsy-proven alcoholic hepatitis. species have been correlated with disease severity and hepatic encephalopathy in liver diseases such as autoimmune hepatitis and cirrhosis. Their abundance has also been recently observed to be increased in alcoholic hepatitis, where postinflammatory infections are known to impact mortality. This case report highlights the possible clinical manifestations that result from significant gut dysbiosis in patients with severe alcoholic hepatitis. Early identification and treatment of bacteremia in susceptible populations could be crucial to survival given this organism's predilection for causing life-threatening infections, including meningitis, endocarditis, and osteomyelitis.
PubMed: 34691793
DOI: 10.1155/2021/9947213 -
Food & Function Nov 2023and species are key regulators of a healthy gut environment through metabolic cross-feeding, influencing lactic acid and short-chain fatty acid (SCFA) levels, which...
and species are key regulators of a healthy gut environment through metabolic cross-feeding, influencing lactic acid and short-chain fatty acid (SCFA) levels, which are crucial for gut health. This study aims to investigate how () and (LA) interact with each other and alleviate dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in a mouse model. We assess their metabolic interactions regarding carbon sources through co-culturing in a modified medium. In the experiments, and LA were inoculated in mono-cultures and co-culture, and viable cell counts, OD, pH, lactic acid, glucose and SCFAs were measured. For the experiment, 60 C57BL/6 mice were randomly divided into five groups and administered and LA alone or in combination oral gavage (1 × 10 CFU mL per day per mouse) for 14 days. On the seventh day, 2.5% DSS was added to the drinking water to induce colitis. The effects of these probiotics on UC were evaluated by assessing intestinal barrier integrity and intestinal inflammation in the gut microenvironment. results demonstrated that co-culturing with LA significantly increased viable cell numbers, lactic acid production, and SCFA production, while reducing pH and glucose levels in the medium. findings revealed that intervention with , particularly in combination with LA, alleviated symptoms, including weight loss, colon shortening, and tissue damage. These probiotics mitigated intestinal inflammation by down-regulating pro-inflammatory molecules, such as IL-6, IL-1β, IL-γ, iNOS, and IFN-γ, as well as oxidative stress markers, including MDA and MPO. Concurrently, they upregulated the activity of anti-inflammatory enzymes, namely, SOD and GSH, and promoted the production of SCFAs. The combined intervention of and LA significantly increased acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, and total SCFAs in cecal contents. Furthermore, the intervention of and LA increased the abundance of beneficial bacteria, such as , while reducing the abundance of harmful bacteria, such as - and , thereby mitigating excessive inflammation. These findings highlight the enhanced therapeutic effects resulting from the interactions between and LA, demonstrating the potential of this combined probiotic approach.
Topics: Animals; Mice; Colitis, Ulcerative; Lactobacillus acidophilus; Veillonella; Mice, Inbred C57BL; Colitis; Colon; Inflammation; Probiotics; Glucose; Lactic Acid; Dextran Sulfate; Disease Models, Animal
PubMed: 37934670
DOI: 10.1039/d3fo03898j -
Microbiome Research Reports 2023There is growing evidence that physical activity modulates gut microbiota composition through complex interactions between diet and microbial species. On the other... (Review)
Review
There is growing evidence that physical activity modulates gut microbiota composition through complex interactions between diet and microbial species. On the other hand, next-generation sequencing techniques include shotgun metagenomics and 16S amplicon sequencing. These methodologies allow a comprehensive characterisation of microbial communities of athletes from different disciplines as well as non-professional players and sedentary adults exposed to training. This systematic review summarises recent applications of next-generation sequencing to characterise the athletic gut microbiome. A systematic review of microbiome research was performed to determine the association of microbiota composition profiles with sports performance. Bibliographic analysis revealed the importance of a novel research trend aiming at deciphering the associations between individual microbial species and sports performance. In addition, literature review highlighted the role of butyrate-producing bacteria such as , , , and unidentified species belonging to , and species in gut health and sports performance across several disciplines. Interestingly, metabolic activities of and involved in branched amino acid and lactate metabolism may contribute to reducing muscular fatigue. Other microbial metabolic pathways of interest involved in carbohydrate metabolism showed increased proportions in athletes´ metagenomes. Future research will aim at developing personalised nutrition interventions to modulate key species associated with certain components of exercise.
PubMed: 38045609
DOI: 10.20517/mrr.2022.16 -
Frontiers in Microbiology 2022Dental caries remains the most common chronic disease in children, and the respective etiology is not fully understood. Though is an important factor in the initiation...
Dental caries remains the most common chronic disease in children, and the respective etiology is not fully understood. Though is an important factor in the initiation and progression of caries, its presence is not always associated with the disease. The existence of caries discordant populations, in which counts do not correlate with caries experience, poses a challenging problem. This study explored the possible correlation of S. and other microorganism levels on caries-associated ecology of caries-concordant and discordant populations. A total of forty-seven children were analyzed in this study and stratified into four clinical groups based on their levels in saliva (HS/LS: High/low ) and caries experience. levels were determined by culture-based selective plating. The salivary microbiome of caries concordant and discordant populations was investigated by 16S rRNA gene sequencing and downstream bioinformatics analysis. The salivary microbial communities significantly clustered based on levels and independent of their caries experience. In addition to levels, significant differences in the abundance of other species were observed between HS and LS groups. Interestingly, disease-associated species such as spp., and spp. were significantly increased in HS groups and may contribute, in combination with , to the caries progression. Furthermore, health-associated species exhibited higher abundance in the LS groups, such as sp., and spp. but their possible contribution to the caries process remains to be elucidated. This study provides evidence that may play a role in shaping the salivary microbial community. Our results highlight that future caries research should consider additional species as health/disease microbial markers in conjunction with to improve diagnosis and caries management of the caries-discordant population.
PubMed: 35250921
DOI: 10.3389/fmicb.2022.782825 -
Frontiers in Cellular and Infection... 2021The estimation of oral microbiome (OM) taxonomic composition in periodontally healthy individuals can often be biased because the clinically periodontally healthy...
The estimation of oral microbiome (OM) taxonomic composition in periodontally healthy individuals can often be biased because the clinically periodontally healthy subjects for evaluation can already experience dysbiosis. Usually, they are included just based on the absence of clinical signs of periodontitis. Additionally, the age of subjects is used to be higher to correspond well with tested groups of patients with chronic periodontitis, a disorder typically associated with aging. However, the dysbiosis of the OM precedes the clinical signs of the disease by many months or even years. The absence of periodontal pockets thus does not necessarily mean also good periodontal health and the obtained image of "healthy OM" can be distorted.To overcome this bias, we taxonomically characterized the OM in almost a hundred young students of dentistry with precise oral hygiene and no signs of periodontal disease. We compared the results with the OM composition of older periodontally healthy individuals and also a group of patients with severe periodontitis (aggressive periodontitis according to former classification system). The clustering analysis revealed not only two compact clearly separated clusters corresponding to each state of health, but also a group of samples forming an overlap between both well-pronounced states. Additionally, in the cluster of periodontally healthy samples, few outliers with atypical OM and two major stomatotypes could be distinguished, differing in the prevalence and relative abundance of two main bacterial genera: and . We hypothesize that the two stomatotypes could represent the microbial succession from periodontal health to starting dysbiosis. The old and young periodontally healthy subjects do not cluster separately but a trend of the OM in older subjects to periodontitis is visible. Several bacterial genera were identified to be typically more abundant in older periodontally healthy subjects.
Topics: Aged; Aggressive Periodontitis; Chronic Periodontitis; Dysbiosis; Humans; Microbiota; Periodontal Pocket
PubMed: 33828997
DOI: 10.3389/fcimb.2021.629723 -
Journal of Clinical Medicine Aug 2020Halitosis is a common ailment concerning 15% to 60% of the human population. Halitosis can be divided into extra-oral halitosis (EOH) and intra-oral halitosis (IOH). The... (Review)
Review
Halitosis is a common ailment concerning 15% to 60% of the human population. Halitosis can be divided into extra-oral halitosis (EOH) and intra-oral halitosis (IOH). The IOH is formed by volatile compounds, which are produced mainly by anaerobic bacteria. To these odorous substances belong volatile sulfur compounds (VSCs), aromatic compounds, amines, short-chain fatty or organic acids, alcohols, aliphatic compounds, aldehydes, and ketones. The most important VSCs are hydrogen sulfide, dimethyl sulfide, dimethyl disulfide, and methyl mercaptan. VSCs can be toxic for human cells even at low concentrations. The oral bacteria most related to halitosis are spp., spp., spp., spp., spp., spp., spp., spp., spp., spp., spp., , and spp. Most bacteria that cause halitosis are responsible for periodontitis, but they can also affect the development of oral and digestive tract cancers. Malodorous agents responsible for carcinogenesis are hydrogen sulfide and acetaldehyde.
PubMed: 32748883
DOI: 10.3390/jcm9082484 -
Frontiers in Cellular and Infection... 2023Previous research has posited a potential correlation between the gut microbiota and the onset of appendicitis; however, the precise causal connection between...
BACKGROUND
Previous research has posited a potential correlation between the gut microbiota and the onset of appendicitis; however, the precise causal connection between appendicitis and the gut microbiota remains an unresolved and contentious issue.
METHODS
In this investigation, we performed a Mendelian randomization (MR) analysis employing publicly accessible summary data extracted from genome-wide association studies (GWAS) to elucidate the potential causal nexus between the gut microbiota and the development of appendicitis. We initially identified instrumental variables (IVs) through a comprehensive array of screening methodologies, subsequently executing MR analyses using the Inverse Variance Weighted (IVW) technique as our primary approach, supplemented by several alternative methods such as MR Egger, weighted median, simple mode, and weighted mode. Additionally, we implemented a series of sensitivity analysis procedures, encompassing Cochran's Q test, MR-Egger intercept test, Mendelian Randomized Polymorphism Residual and Outlier (MR-PRESSO) test, and a leave-one-out test, to affirm the robustness and validity of our findings.
RESULTS
Our investigation indicates that an elevated prevalence of Deltaproteobacteria, Christensenellaceae, Desulfovibrionaceae, Eubacterium ruminantium group, Lachnospiraceae NK4A136 group, Methanobrevibacter, Desulfovibrionales, and Euryarchaeota is inversely associated with the risk of appendicitis. Conversely, we observed a positive correlation between an increased abundance of Family XIII, Howardella, and Veillonella and the susceptibility to appendicitis. Sensitivity analyses have corroborated the robustness of these findings, and Mendelian randomization analyses provided no indications of reverse causality.
CONCLUSION
Our Mendelian randomization (MR) analysis has unveiled potential advantageous or detrimental causal associations between the gut microbiota and the occurrence of appendicitis. This study offers novel theoretical and empirical insights into the understanding of appendicitis pathogenesis, along with its implications for preventive and therapeutic strategies.
Topics: Humans; Gastrointestinal Microbiome; Appendicitis; Genome-Wide Association Study; Mendelian Randomization Analysis; Causality; Clostridiales
PubMed: 38162578
DOI: 10.3389/fcimb.2023.1320992 -
IDCases 2019A 79-year-old woman with a history of total hysterectomy for cervical cancer with ureterocutaneostomy presented with high fever. She had tenderness and a hard lump...
A 79-year-old woman with a history of total hysterectomy for cervical cancer with ureterocutaneostomy presented with high fever. She had tenderness and a hard lump around the ureterocutaneostomy site. Computed tomography scan revealed 1.5 cm ureteral calculus in ureterocutaneous fistula (Fig. 1A) associated with bilateral hydronephrosis (Fig. 1B) and we performed a transureteral stent insertion. Blood culture grew methicillin-sensitive (MSSA), , species and and urine culture revealed , MSSA, and . The patient's clinical signs and symptoms gradually improved with ampicillin/sulbactam. Patients with urinary diversions including ureterocutaneostomy and iliac conduits are at increased risk of urolithiasis (1), which can cause sepsis, pyelonephritis, and renal insufficiency (2). Since most patients become colonized with a multitude of bacteria including and skin flora such as and spp., we should empirically treat with broad-spectrum antimicrobials until the culture results are available. Early diagnosis and urological intervention are required because it can be life-threatening with delayed treatment.
PubMed: 31720220
DOI: 10.1016/j.idcr.2019.e00624 -
Brain, Behavior, and Immunity May 2024Gut microbiota communicates bidirectionally with the brain through the nervous, immune, and endocrine systems of the gut. In our preliminary study, the fecal microbiota...
Gut microbiota communicates bidirectionally with the brain through the nervous, immune, and endocrine systems of the gut. In our preliminary study, the fecal microbiota of volunteers with mild cognitive impairment (Fmci) exhibited a higher abundance of Escherichia fergusonii (NK2001), Veillonella infantium (NK2002), and Enterococcus faecium (NK2003) populations compared with those of healthy volunteers. Therefore, we examined the effects of Fmci, NK2001 (gram-negative), NK2002 (gram-negative-like), and NK2003 (gram-positive) on cognitive impairment-like behavior, neuroinflammation, and colitis in mice with or without antibiotics. Fmci transplantation increased cognitive impairment-like behavior, hippocampal tumor necrosis factor (TNF)-α expression, and the size of toll-like receptor (TLR)4Iba1, TLR2Iba1, and NF-κBIba1 cell populations independent of antibiotic treatment. Oral gavage of NK2001, NK2002, or NK2003, which induced TNF-α expression in Caco-2 cells, significantly increased cognitive impairment-like behavior and hippocampal TNF-α expression and Iba1-positive cell populations and decreased brain-derived neurotrophic factor (BDNF) expression in mice. Celiac vagotomy significantly decreased NK2001- or NK2002-induced cognitive impairment-like behavior and hippocampal Iba1 cell population and TNF-α expression and increased NK2001- or NK2002-suppressed hippocampal BDNF expression. However, NK2003-induced cognitive impairment-like behavior and hippocampal Iba1 cell population and TNF-α expression were partially, but not significantly, attenuated by celiac vagotomy. Furthermore, celiac vagotomy did not affect NK2001-, NK2002-, or NK2003-induced lipopolysaccharide (LPS) levels in the blood and feces and TNF-α expression and NF-κB-positive cell population in the colon. In conclusion, LPS-producing NK2001 and NK2002 and LPS-nonproducing NK2003 may induce NF-κB-mediated neuroinflammation through the translocation of byproducts such as LPS and peptidoglycan into the brain through gut-blood/vagus nerve-brain and gut-blood-brain pathways, respectively, resulting in cognitive impairment.
Topics: Humans; Mice; Animals; Lipopolysaccharides; NF-kappa B; Brain-Derived Neurotrophic Factor; Tumor Necrosis Factor-alpha; Neuroinflammatory Diseases; Caco-2 Cells; Cognitive Dysfunction; Vagus Nerve; Mice, Inbred C57BL; Escherichia; Veillonella
PubMed: 38428648
DOI: 10.1016/j.bbi.2024.02.031 -
Cancer Reports (Hoboken, N.J.) Nov 2023Gut microbiota dictates the fate of several diseases, including cancer. Most gastric cancers (GC) belong to gastric adenocarcinomas (GAC). Helicobacter pylori colonizes... (Review)
Review
Gut microbiota dictates the fate of several diseases, including cancer. Most gastric cancers (GC) belong to gastric adenocarcinomas (GAC). Helicobacter pylori colonizes the gastric epithelium and is the causative agent of 75% of all stomach malignancies globally. This bacterium has several virulence factors, including cytotoxin-associated gene A (CagA), vacuolating cytotoxin (VacA), and outer membrane proteins (OMPs), all of which have been linked to the development of gastric cancer. In addition, bacteria such as Escherichia coli, Streptococcus, Clostridium, Haemophilus, Veillonella, Staphylococcus, and Lactobacillus play an important role in the development of gastric cancer. Besides, lactic acid bacteria (LAB) such as Bifidobacterium, Lactobacillus, Lactococcus, and Streptococcus were found in greater abundance in GAC patients. To identify potential diagnostic and therapeutic interventions for GC, it is essential to understand the mechanistic role of H. pylori and other bacteria that contribute to gastric carcinogenesis. Furthermore, understanding bacteria-host interactions and bacteria-induced inflammatory pathways in the host is critical for developing treatment targets for gastric cancer.
Topics: Humans; Bacterial Proteins; Antigens, Bacterial; Stomach Neoplasms; Microbiota; Helicobacter pylori; Cytotoxins
PubMed: 37530125
DOI: 10.1002/cnr2.1878