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International Journal of Rheumatic... Jun 2024Alterations in gut microbiota have been implicated in the pathogenesis of ankylosing spondylitis (AS), but the underlying mechanisms remain elusive. This study aims to...
OBJECTIVE
Alterations in gut microbiota have been implicated in the pathogenesis of ankylosing spondylitis (AS), but the underlying mechanisms remain elusive. This study aims to investigate changes in gut microbiota and metabolites in individuals with AS before and after treatment with secukinumab, to identify the biological characteristics specific to AS patients and investigate the potential biomarkers, for optimizing therapeutic strategies more effectively.
METHODS
Fecal microbiome data were collected from 30 AS patients before and after secukinumab therapy and compared with data from 40 healthy controls (HC). Additionally, we analyzed the metabolic profile of both groups from plasma.
RESULTS
Findings indicated that the treatment-induced changes in the composition of several crucial bacterial groups, including Megamonas, Prevotella_9, Faecalibacterium, Roseburia, Bacteroides, and Agathobacter. Post-treatment, these groups exhibited a distribution more akin to that of the healthy populations compared with their pretreatment status. We identified three gut microbial taxa, namely Prevotellaceae_bacterium_Marseille_P2831, Prevotella_buccae, and Elusimicrobiota, as potential biomarkers for diagnosing individuals at a higher risk of developing AS and assessing disease outcomes. Plasma metabolomics analysis revealed 479 distinct metabolites and highlighted three disrupted metabolic pathways. Integration of microbiome and metabolomics datasets demonstrated a significant degree of correlation, underscoring the impact of the microbiome on metabolic activity.
CONCLUSION
Secukinumab can restore the balance of the gut microbiome and metabolites in AS patients, rendering them more similar to those found in the healthy population. The analysis of microbiome and metabolomics data have unveiled some candidate biomarkers capable of evaluating treatment efficacy.
Topics: Humans; Spondylitis, Ankylosing; Gastrointestinal Microbiome; Male; Antibodies, Monoclonal, Humanized; Female; Adult; Feces; Metabolomics; Treatment Outcome; RNA, Ribosomal, 16S; Case-Control Studies; Ribotyping; Middle Aged; Bacteria; Biomarkers; Predictive Value of Tests; Dysbiosis
PubMed: 38923187
DOI: 10.1111/1756-185X.15218 -
The Journal of Antimicrobial... Apr 2024Recently, reports on antimicrobial-resistant Bacteroides and Prevotella isolates have increased in the Netherlands. This urged the need for a surveillance study on the...
Antimicrobial susceptibility profile of clinically relevant Bacteroides, Phocaeicola, Parabacteroides and Prevotella species, isolated by eight laboratories in the Netherlands.
OBJECTIVES
Recently, reports on antimicrobial-resistant Bacteroides and Prevotella isolates have increased in the Netherlands. This urged the need for a surveillance study on the antimicrobial susceptibility profile of Bacteroides, Phocaeicola, Parabacteroides and Prevotella isolates consecutively isolated from human clinical specimens at eight different Dutch laboratories.
METHODS
Each laboratory collected 20-25 Bacteroides (including Phocaeicola and Parabacteroides) and 10-15 Prevotella isolates for 3 months. At the national reference laboratory, the MICs of amoxicillin, amoxicillin/clavulanic acid, piperacillin/tazobactam, meropenem, imipenem, metronidazole, clindamycin, tetracycline and moxifloxacin were determined using agar dilution. Isolates with a high MIC of metronidazole or a carbapenem, or harbouring cfiA, were subjected to WGS.
RESULTS
Bacteroides thetaiotaomicron/faecis isolates had the highest MIC90 values, whereas Bacteroides fragilis had the lowest MIC90 values for amoxicillin/clavulanic acid, piperacillin/tazobactam, meropenem, imipenem and moxifloxacin. The antimicrobial profiles of the different Prevotella species were similar, except for amoxicillin, for which the MIC50 ranged from 0.125 to 16 mg/L for Prevotella bivia and Prevotella buccae, respectively. Three isolates with high metronidazole MICs were sequenced, of which one Bacteroides thetaiotaomicron isolate harboured a plasmid-located nimE gene and a Prevotella melaninogenica isolate harboured a nimA gene chromosomally.Five Bacteroides isolates harboured a cfiA gene and three had an IS element upstream, resulting in high MICs of carbapenems. The other two isolates harboured no IS element upstream of the cfiA gene and had low MICs of carbapenems.
CONCLUSIONS
Variations in resistance between species were observed. To combat emerging resistance in anaerobes, monitoring resistance and conducting surveillance are essential.
Topics: Humans; Meropenem; Moxifloxacin; Netherlands; Metronidazole; Laboratories; Bacteroides; Anti-Bacterial Agents; Carbapenems; Bacteroides fragilis; Imipenem; Anti-Infective Agents; Microbial Sensitivity Tests; Piperacillin; Tazobactam; Prevotella; Amoxicillin; Clavulanic Acid
PubMed: 38394460
DOI: 10.1093/jac/dkae043 -
Archive of Clinical Cases 2023is a gram-negative obligate anaerobe mainly associated with infections of odontogenic origin. Non-oral monomicrobial infection by these obligate anaerobic bacteria is...
is a gram-negative obligate anaerobe mainly associated with infections of odontogenic origin. Non-oral monomicrobial infection by these obligate anaerobic bacteria is rare. Only a few cases of monomicrobial non-oral infections by have been reported in the literature. We are reporting a case of unilateral complicated pleural empyema in a patient with bronchial asthma infected by . Pleural fluid aerobic culture and blood culture reports were sterile. No acid-fast bacilli were detected by Acid Fast Bacilli (AFB) staining, and cartridge-based nucleic acid assay test (CBNAAT) reports were negative for . The isolate, was found susceptible to Metronidazole (MIC = 3 μg/ml) and resistant to Clindamycin (MIC = 256 μg/ml). In view of rising trends of antimicrobial resistance among anaerobes, it is recommended to perform anaerobic culture and sensitivity testing in clinically suspected cases of pleuropulmonary infection for appropriate diagnosis and optimal patient management. Clindamycin should be used with caution for empiric treatment.
PubMed: 38026109
DOI: 10.22551/2023.41.1004.10263 -
Cureus Oct 2023We present the case of a 53-year-old male with complicated left-sided parapneumonic effusion due to and . Management required video-assisted thoracoscopic surgery and...
We present the case of a 53-year-old male with complicated left-sided parapneumonic effusion due to and . Management required video-assisted thoracoscopic surgery and partial decortication of the left lung. Complications during the hospital stay were extensive, including sepsis, acute hypoxic respiratory failure, alcohol withdrawal, and transient ischemic attack.
PubMed: 38022023
DOI: 10.7759/cureus.47443 -
Orthodontics & Craniofacial Research Feb 2024To investigate the salivary bacterial communities during the first 6-month orthodontic treatment with Clear Aligners (CA) and Fixed Appliances (FA), and its correlation...
OBJECTIVE
To investigate the salivary bacterial communities during the first 6-month orthodontic treatment with Clear Aligners (CA) and Fixed Appliances (FA), and its correlation with clinical periodontal parameters.
MATERIALS AND METHODS
Saliva and periodontal parameters were sampled from individuals wearing CA or FA before treatment (T0), and after 3- (T3) and 6-month (T6) treatments. Salivary bacterial communities characterized based on the 16S rRNA V3-V4 region were compared between FA and CA and correlated with clinical periodontal parameters.
RESULTS
Probing Depth (PD) significantly increased at T6 in the FA group versus T0, whereas it remained stable in the CA group. The Shannon and Pielou indices were significantly higher in the FA group and significantly positively correlated with periodontal inflammation parameters. β-diversity analysis revealed distinct communities between the FA group and CA group at T6. The relative abundances of 3 genera and 15 species were significantly higher in the FA group. Among the above appliance-type related taxa, bacterial genera Selenomonas, Stomatobaculum, Olsenella and Faecalicoccus and bacterial species Selenomonas_sputigena, Dialister_invisus, Olsenella_profus, Prevotella_buccae, Cryptobacterium_curtum and Clostridium_spiroforme were significantly positively associated with periodontal parameters.
CONCLUSIONS
Orthodontic treatments trigger appliance-related salivary bacterial communities, highlighting the importance of developing appliance-orientated periodontal strategies during orthodontic treatments. Salivary bacterial communities harboured by patients wearing FA possess higher bacterial parameters which were associated with increasing PD, PI and Gingival Index.
Topics: Humans; RNA, Ribosomal, 16S; Orthodontic Appliances; Orthodontic Appliances, Fixed; Saliva; Microbiota
PubMed: 37985447
DOI: 10.1111/ocr.12733 -
Cureus May 2023Necrotizing infections of deep neck spaces are a group of life-threatening infectious diseases acquired through trauma or as a descending infection from an odontogenic...
Necrotizing infections of deep neck spaces are a group of life-threatening infectious diseases acquired through trauma or as a descending infection from an odontogenic source. The isolation of pathogens is unusual because of the anaerobic nature of the infection; however, one way to achieve this is through the use of automated microbiological methods like matrix-assisted laser desorption/ionization and time-of-flight (MALDI-TOF) following standard microbiology protocols for analyzing samples from potential anaerobic infections. We present a case of a patient without risk factors for descending necrotizing mediastinitis with isolation managed at the intensive care unit with a multidisciplinary team. We present our approach and how we successfully treat this complicated infection.
PubMed: 37398802
DOI: 10.7759/cureus.39703 -
Science (New York, N.Y.) Apr 2023Type VI CRISPR-Cas systems use RNA-guided ribonuclease (RNase) Cas13 to defend bacteria against viruses, and some of these systems encode putative membrane proteins that...
Type VI CRISPR-Cas systems use RNA-guided ribonuclease (RNase) Cas13 to defend bacteria against viruses, and some of these systems encode putative membrane proteins that have unclear roles in Cas13-mediated defense. We show that Csx28, of type VI-B2 systems, is a transmembrane protein that assists to slow cellular metabolism upon viral infection, increasing antiviral defense. High-resolution cryo-electron microscopy reveals that Csx28 forms an octameric pore-like structure. These Csx28 pores localize to the inner membrane in vivo. Csx28's antiviral activity in vivo requires sequence-specific cleavage of viral messenger RNAs by Cas13b, which subsequently results in membrane depolarization, slowed metabolism, and inhibition of sustained viral infection. Our work suggests a mechanism by which Csx28 acts as a downstream, Cas13b-dependent effector protein that uses membrane perturbation as an antiviral defense strategy.
Topics: CRISPR-Cas Systems; Cryoelectron Microscopy; Membrane Proteins; RNA, Viral; Bacterial Proteins; Endodeoxyribonucleases; CRISPR-Associated Proteins; RNA Cleavage; Bacteriophages; Bacteriophage lambda; Escherichia coli; Prevotella
PubMed: 37104586
DOI: 10.1126/science.abm1184 -
Microbial Pathogenesis Mar 2023This study is an investigation of anaerobic nitrite and fumarate reduction/respiration abilities of two characterised Prevotella species namely Prevotella nigrescens...
OBJECTIVE
This study is an investigation of anaerobic nitrite and fumarate reduction/respiration abilities of two characterised Prevotella species namely Prevotella nigrescens (SS6B) and Prevotella buccae (GS6B) isolated from the periodontal pockets of chronic periodontitis (ChP) patients.
METHODS
Isolation and identification of the periodontal bacteria from 20 patients showing clinical symptoms of ChP. Characterisation of anaerobic nitrite and fumarate reduction was done in P. nigrescens (SS6B) and P. buccae (GS6B) using reduction assays, inhibition assays with use of specific inhibitors, growth assays and enzyme activity assays. Degenerate PCR was used to detect and amplify nitrite reductase (nrfA) and fumarate reductase (frdA) gene sequences in these Prevotella isolates. In addition, molecular and in silico analysis of the amplified anaerobic reductase gene sequences was performed using NCBI conserved domain analysis, Interpro database and MegaX.
RESULTS
We provided experimental evidence for presence of active nitrite and fumarate reductase activities through enzyme activity, reduction, inhibitor and growth assays. Moreover, we were able to detect presence of 505 bps nrfA gene fragment and 400 bps frdA gene fragment in these Prevotella spp. These fragments show similarity to multiheme ammonia forming cytochrome c nitrite reductases and fumarate reductases flavoprotein subunit, respectively.
CONCLUSION
Anaerobic nitrite and fumarate respiration abilities in P. nigrescens and P. buccae isolates appear to be important for detoxification process and growth, respectively.
Topics: Humans; Chronic Periodontitis; Prevotella nigrescens; Nitrites; Succinate Dehydrogenase
PubMed: 36739100
DOI: 10.1016/j.micpath.2023.106022 -
Journal of Periodontal & Implant Science Feb 2023The objective of this study was to analyze the microbial profile of individuals with peri-implantitis (PI) compared to those of periodontally healthy (PH) subjects and...
PURPOSE
The objective of this study was to analyze the microbial profile of individuals with peri-implantitis (PI) compared to those of periodontally healthy (PH) subjects and periodontitis (PT) subjects using Illumina sequencing.
METHODS
Buccal, supragingival, and subgingival plaque samples were collected from 109 subjects (PH: 30, PT: 49, and PI: 30). The V3-V4 region of 16S rRNA was sequenced and analyzed to profile the plaque microbiota.
RESULTS
Microbial community diversity in the PI group was higher than in the other groups, and the 3 groups showed significantly separated clusters in the buccal samples. The PI group showed different patterns of relative abundance from those in the PH and PT groups depending on the sampling site at both genus and phylum levels. In all samples, some bacterial species presented considerably higher relative abundances in the PI group than in the PH and PT groups, including , , , , , , , , and . Network analysis identified that several well-known periodontal pathogens and newly recognized bacteria were closely correlated with each other.
CONCLUSIONS
The composition of the microbiota was considerably different in PI subjects compared to PH and PT subjects, and these results could shed light on the mechanisms involved in the development of PI.
PubMed: 36468472
DOI: 10.5051/jpis.2202080104 -
Oral Diseases Nov 2023To investigate the association between Alzheimer's disease (AD) and periodontitis in the aspects of periodontal status, serological markers, and oral microbiome.
OBJECTIVE
To investigate the association between Alzheimer's disease (AD) and periodontitis in the aspects of periodontal status, serological markers, and oral microbiome.
MATERIALS AND METHODS
Twenty AD and 20 healthy subjects were enrolled in this age- and gender-matched case-control study. Clinical periodontal parameters and serum biomarkers, including amyloid β (Aβ ), Tau, phosphorylated Tau (pTau), triglyceride, pro-inflammatory cytokines, and anti-Porphyromonas gingivalis lipopolysaccharide (LPS) antibody were examined. The saliva samples were analyzed for oral microbiome composition.
RESULTS
Alzheimer's disease patients with Clinical Dementia Rating (CDR) ≥1 exhibited significantly more clinical attachment loss (CAL) than those with lower CDR. The levels of serum Tau protein, hsCRP and anti-P. gingivalis LPS antibody were markedly elevated in the AD group compared with the control group. Serum pTau protein level was positively correlated with anti-P. gingivalis LPS antibody titer. Moreover, the increased abundances of Capnocytophaga sp ora clone DZ074, Eubacterium infirmum, Prevotella buccae, and Selenomonas artemidis were detected in the AD group. Interestingly, serum levels of Aβ pTau, and anti-P. gingivalis LPS antibody were strongly related to the gene upregulation in human pathogen septicemia.
CONCLUSIONS
Our study suggested the association of periodontal infection and oral microbiome with AD. Further large-scale studies with longitudinal follow-up are warranted.
Topics: Humans; Alzheimer Disease; Amyloid beta-Peptides; Case-Control Studies; Lipopolysaccharides; Periodontitis
PubMed: 35950713
DOI: 10.1111/odi.14348