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BMC Microbiology Oct 2020Antibiotic-associated diarrhea (AAD), defined as diarrhea that occurs in association with the administration of antibiotics and without another clear etiology, is one of...
BACKGROUND
Antibiotic-associated diarrhea (AAD), defined as diarrhea that occurs in association with the administration of antibiotics and without another clear etiology, is one of the most common adverse drug events of antibiotics therapy. We established a diarrhea model induced by gentamycin and cefradine to investigate the microbiota characteristics in the intestinal lumen of mice with AAD and provide insights into noteworthy bacteria related to gentamicin and cefradine-associated diarrhea.
RESULTS
The number of OTUs in the model group and the normal group was 983 and 2107, respectively, and 872 identical OTUs were shared between two groups. Species richness and species diversity of intestinal microbe were altered by antibiotics administration. PCoA showed a clear separation between AAD and health control. The dominant phyla of AAD mice were Firmicutes (52.63%) and Proteobacteria (46.37%). Among the genus with top 20 abundance, the relative abundance of 7 genera, Ruminococcus, Blautia, Enterococcus, Eubacterium, Clostridium, Coprococcus, and Aerococcus, were enriched in the model group. Based upon the LEfSe analysis, Enterococcus, Eubacterium, Ruminococcus, and Blautia were identified as potential biomarkers for AAD.
CONCLUSIONS
The bacterial diversity of the intestinal lumen was diminished after gentamicin and cefradine administration. The alterations in the abundance and composition of gut microbiota further led to the dysfunction of gut microbiota. More specifically, gentamicin and cefradine significantly increased the abundance of the opportunistic pathogens, of which Enterococcus and Clostridium were the most prominent and most worthy of attention.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Diarrhea; Female; Gastrointestinal Microbiome; Male; Mice; RNA, Ribosomal, 16S
PubMed: 33059603
DOI: 10.1186/s12866-020-01999-x -
Journal of Medical Microbiology Jul 2021Periodontitis, one of the most common oral disorders in sheep, is caused by a mixed and opportunistic microbiota that severely affects the health and welfare of...
Periodontitis, one of the most common oral disorders in sheep, is caused by a mixed and opportunistic microbiota that severely affects the health and welfare of animals. However, little is known about the ecological processes involved and the composition of the microbiota associated with the development of the disease. Using high-throughput sequencing of the 16S ribosomal RNA gene and network analysis it would be possible to discriminate the microbiomes of clinically healthy sheep and those with periodontitis and possibly identify the key microorganisms associated with the disease. The present study aimed to characterise the composition of dental microbiomes and bacterial co-occurrence networks in clinically healthy sheep and animals with periodontitis. Dental biofilm samples were collected from ten sheep with periodontitis and ten clinically healthy animals. Bacteria were identified using high-throughput sequencing of the 16S ribosomal RNA gene. The most prevalent genera in the dental microbiota of sheep with periodontitis were , , and . In clinically healthy animals, the most significant genera were unclassified and was found at high prevalence in the microbiomes of both groups. The dental microbiota of sheep in the two clinical conditions presented different profiles and the diversity and richness of bacteria was greater in the diseased animals. Network analyses showed the presence of a large number of antagonistic interactions between bacteria in the dental microbiota of animals with periodontitis, indicating the occurrence of a dysbiotic community. Through the interrelationships, members of the genus are likely to be key pathogens, both in the dental microbiota of healthy animals and those with periodontitis. stood out among the top three nodes with more centrality and the largest number of hubs in the networks of animals with periodontitis. The dental biofilm microbiota associated with ovine periodontitis is dysbiotic and with significant antagonistic interactions, which discriminates healthy animals from diseased animals and highlights the importance of key bacteria, such as , , and species.
Topics: Animals; Bacteria; Biofilms; Ecology; High-Throughput Nucleotide Sequencing; Microbiota; Periodontitis; RNA, Ribosomal, 16S; Sheep
PubMed: 34313584
DOI: 10.1099/jmm.0.001396 -
Marine Drugs Sep 2018Many marine bacteria secrete exopolysaccharides (EPSs), which are made up of a substantial component of the macro-molecules surrounding cells. Recently, the wide demand...
Many marine bacteria secrete exopolysaccharides (EPSs), which are made up of a substantial component of the macro-molecules surrounding cells. Recently, the wide demand for EPSs for food, cosmetics, pharmaceutical and other applications has led to great interest in them. In this study, an EPS produced by marine bacteria HZ strains (EPS-A) was isolated and purified to examine its structure and biological function. The molecular weight of EPS-A analyzed by high-performance liquid gel filtration chromatography (HPGFC) is found to have a number average of 2.22 × 10⁵ and weight average of 2.84 × 10⁵, respectively. High-performance liquid chromatography (HPLC) and Fourier-transform⁻infrared (FT⁻IR) analysis indicate that EPS-A was a polysaccharide composed of glucose and a little mannose. In addition, the flocculating rate of sewage of EPS-A was 79.90%. The hygroscopicity studies showed that hygroscopicity of EPS-A was higher than chitosan but lower than that of sodium hyaluronate. The moisture retention of EPS-A showed similar retention activity to both chitosan and sodium hyaluronate. EPS-A also can scavenge free radicals including both OH• free radical and O₂• free radical and the activity to O₂• free radical is similar to vitamin C. Safety assessment on mice indicated that the EPS-A is safe for external use and oral administration. EPS-A has great potential for applications in medicine due to its characteristics mentioned above.
Topics: Administration, Oral; Aerococcus; Animals; Aquatic Organisms; Chromatography, Gel; Drug Evaluation, Preclinical; Female; Free Radical Scavengers; Free Radicals; Mice; Molecular Weight; Polysaccharides, Bacterial; Spectroscopy, Fourier Transform Infrared; Toxicity Tests, Acute
PubMed: 30223612
DOI: 10.3390/md16090337 -
Journal of Dairy Science May 2021The objective of this prospective cohort study was to explore associations between intramammary infection (IMI) in late-lactation cows and postcalving udder health and...
Postcalving udder health and productivity in cows approaching dry-off with intramammary infections caused by non-aureus Staphylococcus, Aerococcus, Enterococcus, Lactococcus, and Streptococcus species.
The objective of this prospective cohort study was to explore associations between intramammary infection (IMI) in late-lactation cows and postcalving udder health and productivity. Cows (n = 2,763) from 74 US dairy herds were recruited as part of a previously published cross-sectional study of bedding management and IMI in late-lactation cows. Each herd was visited twice for sampling. At each visit, aseptic quarter milk samples were collected from 20 cows approaching dry-off (>180 d pregnant), which were cultured using standard bacteriological methods and MALDI-TOF for identification of isolates. Quarter-level culture results were used to establish cow-level IMI status at enrollment. Cows were followed from enrollment until 120 d in milk (DIM) in the subsequent lactation. Herd records were used to establish whether subjects experienced clinical mastitis or removal from the herd, and DHIA test-day data were used to record subclinical mastitis events (somatic cell count >200,000 cells/mL) and milk yield (kg/d) during the follow-up period. Cox regression and generalized estimating equations were used to evaluate the associations between IMI and the outcome of interest. The presence of late-lactation IMI caused by major pathogens was positively associated with postcalving clinical mastitis [hazard ratio = 1.5, 95% confidence interval (CI): 1.2, 2.0] and subclinical mastitis (risk ratio = 1.5, 95% CI: 1.3, 1.9). Species within the non-aureus Staphylococcus (NAS) group varied in their associations with postcalving udder health, with some species being associated with increases in clinical and subclinical mastitis in the subsequent lactation. Late-lactation IMI caused by Streptococcus and Streptococcus (Strep)-like organisms, other than Aerococcus spp. (i.e., Enterococcus, Lactococcus, and Streptococcus spp.) were associated with increases in postcalving clinical and subclinical mastitis. Test-day milk yield from 1 to 120 DIM was lower (-0.9 kg, 95% CI: -1.6, -0.3) in late-lactation cows with any IMI compared with cows without IMI. No associations were detected between IMI in late lactation and risk for postcalving removal from the herd within the first 120 DIM. Effect estimates reported in this study may be less than the underlying quarter-level effect size for IMI at dry-off and postcalving clinical and subclinical mastitis, because of the use of late-lactation IMI as a proxy for IMI at dry-off and the use of cow-level exposure and outcome measurements. Furthermore, the large number of models run in this study (n = 94) increases the chance of identifying chance associations. Therefore, confirmatory studies should be conducted. We conclude that IMI in late lactation may increase risk of clinical and subclinical mastitis in the subsequent lactation. The relationship between IMI and postcalving health and productivity is likely to vary among pathogens, with Staphylococcus aureus, Streptococcus spp., Enterococcus spp., and Lactococcus spp. being the most important pathogens identified in the current study.
Topics: Aerococcus; Animals; Cattle; Cattle Diseases; Cell Count; Cross-Sectional Studies; Enterococcus; Female; Lactation; Lactococcus; Mammary Glands, Animal; Mastitis, Bovine; Milk; Pregnancy; Prospective Studies; Staphylococcus; Streptococcus
PubMed: 33685704
DOI: 10.3168/jds.2020-19288 -
Journal of Biotechnology Feb 2024l-Lactate oxidase has important applications in biosensing and finds increased use in biocatalysis. The enzyme has been characterized well, yet its immobilization has...
l-Lactate oxidase has important applications in biosensing and finds increased use in biocatalysis. The enzyme has been characterized well, yet its immobilization has not been explored in depth. Here, we studied immobilization of Aerococcus viridansl-lactate oxidase on porous carriers of variable matrix material (polymethacrylate, polyurethane, agarose) and surface functional group (amine, Ni-loaded nitrilotriacetic acid (NiNTA), epoxide). Carrier activity (A) and immobilized enzyme effectiveness (ɳ) were evaluated in dependence of protein loading. Results show that efficient immobilization (A: up to 1450 U/g carrier; ɳ: up to 65%) requires a hydrophilic carrier (agarose) equipped with amine groups. The value of ɳ declines sharply as A increases, probably due to transition into diffusional regime. Untagged l-lactate oxidase binds to NiNTA carrier similarly as N-terminally His-tagged enzyme. Lixiviation studies reveal quasi-irreversible enzyme adsorption on NiNTA carrier while partial release of activity (≤ 25%) is shown from amine carrier. The desorbed enzyme exhibits the same specific activity as the original l-lactate oxidase. Collectively, our study identifies basic requirements of l-lactate oxidase immobilization on solid carrier and highlights the role of ionic interactions in enzyme-surface adsorption.
Topics: Aerococcus; Sepharose; Mixed Function Oxygenases; Enzymes, Immobilized; Amines
PubMed: 38280467
DOI: 10.1016/j.jbiotec.2024.01.011 -
Experimental Gerontology Dec 2022We induced the AD-like rat models injected by AlCl and D-galactose, to explore the effects of an oral treatment of A. muciniphila on AD-like rats with periodontitis and...
AIMS
We induced the AD-like rat models injected by AlCl and D-galactose, to explore the effects of an oral treatment of A. muciniphila on AD-like rats with periodontitis and its possible mechanism.
MAIN METHODS
We used Morris water maze test and micro-CT to assess the cognitive impairment and bone loss; Aβ1-42 deposition was tested by IHC; Serum LPS level and TG, HDL-C and AST/ALT levels were detected by LAL Test and biochemical tests; The gut microbiota was analyzed by 16S rRNA gene sequence.
KEY FINDINGS
We found that A. muciniphila could alleviate AD-like rats' cognitive impairment and mitigate ligature-induced periodontitis. Furthermore, A. muciniphila reduced Aβ1-42 deposition in the cortex and regions of the rats' brain, and altered TG, HDL-C and AST/ALT levels but had little ability to change circulating LPS level and cross the blood-brain barrier. Notably, A. muciniphila treatment could improve the abundance of some short chain fatty acid (SCFA)-producing or neurotransmitter-producing gut microbiome such as Blautia, Staphylococcus and Lactococcus, while the abundance of pathogenic Aerococcus and Streptococcus, which were associated inflammation, were decreased.
SIGNIFICANCE
Our findings suggested that A. muciniphila has a remissive effect on AD-like pathologies, potentially by regulating gut-brain axis through altering composition and function of gut microbial community or moderating peripheral circulation metabolism.
Topics: Animals; Rats; Alzheimer Disease; Aluminum Chloride; Galactose; RNA, Ribosomal, 16S; Lipopolysaccharides; Verrucomicrobia; Periodontitis; Probiotics
PubMed: 36152776
DOI: 10.1016/j.exger.2022.111959 -
Environmental Research Apr 2019The airborne fungal and bacterial species present in pig farm dust have not been well characterised even though these bioaerosols are known to cause inflammation and...
The airborne fungal and bacterial species present in pig farm dust have not been well characterised even though these bioaerosols are known to cause inflammation and other airway maladies. In this study, the microbial species and composition in airborne dust within and between pig farms were investigated. Passively sedimenting dust from six pig farms were collected using electrostatic dust collectors. The bacterial and fungal species were identified using matrix-assisted laser desorption-ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and next generation sequencing (NGS). Dust samples taken within the same stable section revealed high resemblance and stability. Constrained statistical analysis of the microbial community compositions indicated that the types of stable did not appear to have a great effect on the bacterial and fungal β-diversity. In contrast to this, the farm from which samples were taken appeared to have the greatest effect on the bacterial β-diversity, but this trend was not observed for the fungal β-diversity. The most common bacteria and fungi according to NGS data were anaerobes typically associated with the pig intestinal tract and yeasts respectively. Bacterial sedimentation varied at a rate between 10 and 10 CFU/m/day, with the most common species after aerobic incubation being Aerococcus viridans and Staphylococcus equorum, while Clostridium perfringens and Staphylococcus simulans were the most common species after anaerobic incubation. A total of 28 different species of bacteria and fungi were classifiable as pathogens. In conclusion, the biodiversity in pig farm dust shows a high diversity of bacterial species. However, samples from the same stable section resembled each other, but also different sections within the same farm also resembled each other, thus indicating a high degree of community stability in the dust source. In regards to fungal identification, the biodiversity was observed to be similar between samples from different stable sections and farms, indicating a higher degree of similarities in the mycobiomes found across pig farms studied.
Topics: Air Microbiology; Animals; Bacteria; Biodiversity; Dust; Environmental Monitoring; Farms; Fungi; Swine
PubMed: 30771719
DOI: 10.1016/j.envres.2019.01.008 -
Federal Practitioner : For the Health... Dec 2022(), considered a rare pathogen, has been identified with increasing frequency in urine cultures. Only 8 cases of spondylodiscitis due to have been reported. Optimal...
BACKGROUND
(), considered a rare pathogen, has been identified with increasing frequency in urine cultures. Only 8 cases of spondylodiscitis due to have been reported. Optimal treatment for invasive infection is undefined. However, the reported cases were treated successfully with diverse antibiotic regimen combinations, all including a β-lactam and beginning with at least 2 weeks of IV antibiotics.
CASE PRESENTATION
A 74-year-old man presented to the emergency department after 2 weeks of midthoracic back pain, lower extremity weakness, gait imbalance, fatigue, anorexia, rigors, and subjective fevers. The patient was presumed to have discitis secondary to a urinary tract infection with possible pyelonephritis and was given empiric vancomycin and ceftriaxone. Spinal magnetic resonance imaging with contrast supported spondylodiscitis. Preliminary results from the admission blood and urine cultures showed gram-positive cocci in clusters.
CONCLUSIONS
urinary tract infection in the absence of obvious predisposing factors should prompt evaluation for urinary outflow obstruction. We suspect a review of a US Department of Veterans Affairs population might uncover a higher incidence of infection than previously suspected.
PubMed: 37025983
DOI: 10.12788/fp.0340 -
European Journal of Clinical... May 2022Our objective was to assess the incidence of bacteraemic Aerococcus urinae cases at Helsinki metropolitan area, Finland, from a 6-year study period (2013 to 2018) and to...
Our objective was to assess the incidence of bacteraemic Aerococcus urinae cases at Helsinki metropolitan area, Finland, from a 6-year study period (2013 to 2018) and to further characterize available cases. The study evaluates the outcome of commonly used cefuroxime treatment and determinate a set of A. urinae in vitro antimicrobial susceptibilities for benzylpenicillin, cefuroxime, and ceftriaxone. Clinical records of A. urinae bacteraemic patients were reviewed retrospectively. Antimicrobial susceptibility testing was performed by disk diffusion, gradient test, and broth microdilution for 139-141 clinical A. urinae isolates. Clinical data of 72/77 patients were combined with the in vitro susceptibilities. We found an increasing number of bacteraemic A. urinae cases within 6-year study period (p = 0.01). The patients were mainly elderly males, and all suffered from underlying conditions. A total of 27.3% of cases (21/77) showed polymicrobial blood cultures. Thirty-day mortality was 22.1%. Cefuroxime was the initial empiric antimicrobial agent given for 66/76 of the patients and treatment outcome was favorable for 20/22 patients who received cefuroxime at least up to day 5. All isolates were susceptible to benzylpenicillin and cefuroxime interpreted by EUCAST breakpoints for Aerococci and PK-PD breakpoints, respectively. MIC determinations gave variable results for ceftriaxone, 2.1-2.9% of the isolates were resistant. To conclude, it seems that the number of bacteraemic Aerococcus urinae cases is increasing at Helsinki metropolitan area, Finland, reflecting the growing blood culture sampling. Clinical A. urinae isolates were susceptible to cefuroxime in vitro. Treatment data indicate that empirical cefuroxime started for possibly urinary tract -derived community-acquired bacteraemia covers A. urinae.
Topics: Aerococcus; Aged; Anti-Bacterial Agents; Bacteremia; Ceftriaxone; Cefuroxime; Disease Susceptibility; Finland; Gram-Positive Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Retrospective Studies
PubMed: 35257275
DOI: 10.1007/s10096-022-04415-6 -
Digestive and Liver Disease : Official... Nov 2023Nonalcoholic steatohepatitis (NASH) is associated with imbalance of gut microbiome, indicating participation of gut environment in hepatic health status. Therefore,...
Nonalcoholic steatohepatitis (NASH) is associated with imbalance of gut microbiome, indicating participation of gut environment in hepatic health status. Therefore, modulating gut environment via fecal microbiota transplantation (FMT) is a promising therapeutic procedure for NASH patients. However, the effect and mechanism of the FMT remains largely unknown. Here, we investigated the gut-liver axis to understand the FMT-mediated hepatic improvement in NASH. Feces from specific pathogen free mice were infused allogeneically into gastrointestinal tract of mice fed with high fat, high cholesterol and fructose (HFHCF), resulting in suppressing hepatic pathogenic events, featured by decreasing inflammatory and fibrotic mediators. The FMT elevated NF-E2-related factor 2 (NRF2), a key transcription factor that regulates antioxidant enzymes, in livers. The HFHCF-induced NASH increased intestinal permeability with abundant Facklamia and Aerococcus, an imbalanced gut environment that was significantly improved by the FMT, characterized with restoration of intestinal barrier function and an enrichment of Clostridium. Notably, the gut environment created by FMT was inferred to produce metabolites from the aromatic biogenic amine degradation pathway, specifically 4-hydroxyphenylacetic acid (4-HPA), which is known to ameliorate liver injury. We suggest that gut-derived molecules, related to hepatic improvement such as 4-HPA are the potential therapeutic agents for preventing and treating NASH.
Topics: Humans; Animals; Mice; Non-alcoholic Fatty Liver Disease; Fecal Microbiota Transplantation; Oxidative Stress; Inflammation
PubMed: 37380586
DOI: 10.1016/j.dld.2023.06.015