Search results for "microbiota."
showing 10 items of 496 documents
A multivariate approach of changes in filamentous, nitrifying and protist communities and nitrogen removal efficiencies during ozone dosage in a full…
2019
[EN] The application of low ozone dosage to minimize the problems caused by filamentous foaming was evaluated in two bioreactors of an urban wastewater treatment plant. Filamentous and nitrifying bacteria, as well as protist and metazoa, were monitored throughout a one-year period by FISH and conventional microscopy to examine the effects of ozone application on these specific groups of microorganisms. Multivariate data analysis was used to determine if the ozone dosage was a key factor determining the low carbon and nitrogen removal efficiencies observed throughout the study period, as well as to evaluate its impact on the biological communities monitored. The results of this study suggest…
Characterization of the microbiota from coelomic fluid of the sea urchin Paracentrotus lividus
2016
The study of the microbiota is a subject of considerable and growing interest since it is drawing new important perspectives in the life sciences concerning the functional relationships between metazoans and microbial cells. In fact, it has already shown that the endogenous microbial community affects various physiological activities of multicellular organisms. The coelomic cavity of echinoderms contains a fluid in which coelomocytes are reported to exert immune functions like phagocytosis, opsonization and production of antimicrobial agents against marine bacteria [1, 2]. However, up to day nothing is known about the endogenous bacterial population of coelomic fluid. We focused on this iss…
Abundant and diverse arsenic‐metabolizing microorganisms in peatlands treating arsenic‐contaminated mining wastewaters
2020
Mining operations produce large quantities of wastewater. At a mine site in Northern Finland, two natural peatlands are used for the treatment of mining‐influenced waters with high concentrations of sulfate and potentially toxic arsenic (As). In the present study, As removal and the involved microbial processes in those treatment peatlands (TPs) were assessed. Arsenic‐metabolizing microorganisms were abundant in peat soil from both TPs (up to 108 cells gdw‐1), with arsenate respirers being about 100 times more abundant than arsenite oxidizers. In uninhibited microcosm incubations, supplemented arsenite was oxidized under oxic conditions and supplemented arsenate was reduced under anoxic con…
Glyphosate residues alter the microbiota of a perennial weed with a minimal indirect impact on plant performance
2021
Abstract Purpose In cold climates, glyphosate residues may linger in soils, with effects on plant–microbe interactions and, consequently, plant performance. Here, we explore the influence of glyphosate residues on the endophytic microbiota (bacteria and fungi) and performance of the perennial nitrogen-fixing weed Lupinus polyphyllus. Methods In a common garden, we grew plants from six populations of L. polyphyllus in glyphosate-treated or untreated control soils, with or without additional phosphorus. We sampled plant microbiota (leaves, roots, nodules) and assessed plant performance based on six traits: height, retrogression probability (i.e. shrinkage), biomass, root:shoot ratio, nodule n…
Periodontitis and mechanisms of cardiometabolic risk: Novel insights and future perspectives
2019
Periodontitis is an infectious and inflammatory disease of the tooth-supporting tissues caused by the accumulation of subgingival plaque and the action of specific periodontopathogenic bacteria. Periodontitis has been associated with cardiovascular diseases and considered a cardiovascular risk factor. Several mechanisms have been proposed to explain this association, such as the infection of atherosclerotic plaques by periodontal pathogens, the pro-atherogenic effect on the lipid profile, the systemic dissemination of pro-inflammatory mediators or the contribution to type 2 diabetes mellitus. Periodontal treatment has also been related to improvement in cardiometabolic risk variables, and o…
Periimplantitis y mucositis periimplantaria: factores de riesgo, diagnóstico y tratamiento
2015
espanolIntroduccion: El objetivo de este trabajo es profundizar en el conocimiento de la enfermedad periimplantaria y los tratamientos existentes descritos en la literatura. Material y metodo: Revision bibliografica de las enfermedades periimplantarias, basada en una busqueda en bases de datos Pubmed, Medline y Cochrane Library, utilizando como palabras clave "periimplantitis, mucositis, tabaquism, oral microbiota, occlusal overload, surgical treatment, antimicrobial therapy, detoxification, regenerative therapy, bone defects". Desarrollo y discusion: Analisis de los factores de riesgo, el diagnostico y el tratamiento de las enfermedades periimplantarias. Conclusiones: Los factores como el …
Butyrate, a postbiotic of intestinal bacteria, affects pancreatic cancer and gemcitabine response in in vitro and in vivo models
2022
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer. The characteristic excessive stromatogenesis accompanying the growth of this tumor is believed to contribute to chemoresistance which, together with drug toxicity, results in poor clinical outcome. An increasing number of studies are showing that gut microbiota and their metabolites are implicated in cancer pathogenesis, progression and response to therapies. In this study we tested butyrate, a product of dietary fibers' bacterial fermentation, whose anticancer and anti-inflammatory functions are known. We provided in vitro evidence that, beside slowing proliferation, butyrate enhanced gemcitabine effectiveness against two hum…
Shedding light on biogas: Phototrophic biofilms in anaerobic digesters hold potential for improved biogas production
2019
Conventional anaerobic digesters intended for the production of biogas usually operate in complete darkness. Therefore, little is known about the effect of light on their microbial communities. In the present work, 16S rRNA gene amplicon Nanopore sequencing and shotgun metagenomic sequencing were used to study the taxonomic and functional structure of the microbial community forming a biofilm on the inner wall of a laboratory-scale transparent anaerobic biodigester illuminated with natural sunlight. The biofilm was composed of microorganisms involved in the four metabolic processes needed for biogas production, and it was surprisingly rich in Rhodopseudomonas faecalis, a versatile bacterium…
The impact of liquid-pressurized extracts of Spirulina, Chlorella and Phaedactylum tricornutum on in vitro antioxidant, antiinflammatory and bacteria…
2022
The impact of Spirulina, Chlorella and Phaeodactylum tricornutum (P. tricornutum) microalgal extracts obtained by pressurized liquid extraction (PLE) on antioxidant and anti-inflammatory activities, microbial growth and in vitro gut microbiota composition was evaluated. PLE, compared to conventional extraction, led to a significant (p < 0.05) increase in proteins, carbohydrates, polyphenols, and antioxidant capacities of the three microalgal extracts. Moreover, Spirulina and P. tricornutum extracts significantly (p < 0.05) reduced the in vitro activation of the inflammatory NF-κB pathway. The microalgal extracts had also an inhibitory effect on the pathogenic bacteria while potential benefi…
Evaluation of Changes in Gut Microbiota in Patients with Crohn’s Disease after Anti-Tnfα Treatment: Prospective Multicenter Observational Study
2020
Background: Crohn’s disease is believed to result from the interaction between genetic susceptibility, environmental factors and gut microbiota, leading to an aberrant immune response. The objectives of this study are to evaluate the qualitative and quantitative changes in the microbiota of patients with Crohn’s disease after six months of anti-tumor-necrosis factor (anti-TNFα) (infliximab or adalimumab) treatment and to determine whether these changes lead to the recovery of normal microbiota when compared to a control group of healthy subjects. In addition, we will evaluate the potential role of the Faecalibacterium prausnitzii/Escherichia coli and Faecalibacterium prausnitzii/Clostridium…