scholarly journals In Vitro Multi-Species Oral Biofilms Grown in Presence of H2O2 Production-Affecting Substrates Show Health-Associated Alterations in Composition, Metabolism and Virulence.

2021 ◽  
Author(s):  
Tim Verspecht ◽  
Dorien Vermeulen ◽  
Wannes Van Holm ◽  
Naiera Zayed ◽  
Kristel Bernaerts ◽  
...  
Keyword(s):  
Therapeutic Strategy ◽  
Virulence Genes ◽  
H2o2 Production ◽  
Oral Microbiota ◽  
Periodontal Pathogens ◽  
Beneficial Effects ◽  
Commensal Species ◽  
Oral Biofilms ◽  
Selection Of

Abstract Modulation of the commensal oral microbiota is a promising preventive or therapeutic strategy for oral health and can for instance be achieved by increasing the abundance and/or activity of certain species. This study evaluated whether 10 selected substrates could modulate in vitro multi-species oral biofilms towards a more health-associated state. These substrates were chosen based on the possibility that they could stimulate H2O2 production by certain commensal species and/or increase their abundance, as previously reported or as hypothesized based on known bacterial H2O2 pathways. Biofilms grown in presence of the substrates at a clinically relevant concentration of 1%(w/v) often showed increased abundances of commensal species and decreased abundances of periodontal pathogens. Furthermore, most biofilms also showed an altered metabolic profile. Effects on the expression of a selection of virulence genes were substrate-dependent, but often a decreased expression of certain genes could be observed. In conclusion, this study found that a selection of substrates chosen for their hypothesized beneficial effects on the commensal oral microbiota were able to modulate in vitro multi-species oral biofilms towards a more health-associated state. These modulatory effects were found to be substrate-dependent.

scholarly journals High-throughput method to test antimicrobial gels against a multispecies oral biofilm

2020 ◽  
Author(s):  
Kanchana Chathoth ◽  
Bénédicte Martin ◽  
Martine Bonnaure-Mallet ◽  
Christine Baysse
Keyword(s):  
Oral Microbiota ◽  
Periodontal Pathogens ◽  
Simple Method ◽  
Flow Cells ◽  
Topical Gel ◽  
Microtiter Plates ◽  
High Throughput Method ◽  
Oral Biofilms ◽  
Gel Formulations

ABSTRACTPeriodontitis, characterized by the damage of the periodontium can eventually lead to tooth loss. Moreover, severe forms of periodontitis are associated with several systemic disorders. The evolution of the disease is linked to the pathogenic switch of the oral microbiota comprising of commensal colonizers and anaerobic pathogens. Treatment with antimicrobial gels has the potential to help eradicate periodontal pathogens. Testing antibacterial gels against in vitro biofilm models is complicated. Recovery of detached and sessile bacteria from in vitro biofilms treated with gel formulations using conventional methods (microtiter plates, μ-slides, flow cells etc.,) may prove arduous. To overcome this challenge, we optimised a simple method using the principle of the Calgary Biofilm Device (CBD) for testing antimicrobial gels against multispecies oral biofilms. First, we established three-species oral biofilms consisting of two periodontal pathogens (Porphyromonas gingivalis, Treponema denticola) and a primary colonizer of the dental plaque (Streptococcus gordonii) on the surface of pegs. Next, a protocol to test gels against oral biofilms was implemented using commercially available gels with different active products. This method enables the analysis of the composition of biofilm and detached/planktonic cells to measure the effect of topical gel formulations/antibacterial gels for the treatment of periodontitis. However, the method is not restricted to oral biofilms and can be adapted for other biofilm-related studies.

scholarly journals Rhizosphere-enriched microbes as a pool to design synthetic communities for reproducible beneficial outputs

2018 ◽  
Author(s):  
Maria-Dimitra Tsolakidou ◽  
Ioannis A. Stringlis ◽  
Natalia Fanega-Sleziak ◽  
Stella Papageorgiou ◽  
Antria Tsalakou ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Fungal Pathogens ◽  
Growth Parameters ◽  
Tomato Plants ◽  
Beneficial Effects ◽  
Negative Effect ◽  
Tomato Growth ◽  
Selection Of

AbstractComposts represent a sustainable way to suppress diseases and improve plant growth. Identification of compost-derived microbial communities enriched in the rhizosphere of plants and characterization of their traits, could facilitate the design of microbial synthetic communities (SynComs) that upon soil inoculation could yield consistent beneficial effects towards plants. Here, we characterized a collection of compost-derived bacteria, previously isolated from tomato rhizosphere, forin vitroantifungal activity against soil-borne fungal pathogens and for their potential to change growth parameters inArabidopsis. We further assessed root-competitive traits in the dominant rhizospheric genusBacillus. Certain isolated rhizobacteria displayed antifungal activity against the tested pathogens and affected growth ofArabidopsis, and Bacilli members possessed several enzymatic activities. Subsequently, we designed two SynComs with different composition and tested their effect onArabidopsisand tomato growth and health. SynCom1, consisting of different bacterial genera, displayed negative effect onArabidopsis in vitro, but promoted tomato growth in pots. SynCom2, consisting of Bacilli, didn’t affectArabidopsisgrowth, enhanced tomato growth and suppressed Fusarium wilt symptoms. Overall, we found selection of compost-derived microbes with beneficial properties in the rhizosphere of tomato plants, and observed that application of SynComs on poor substrates can yield reproducible plant phenotypes.

scholarly journals Systematic Approach to Developing Splice Modulating Antisense Oligonucleotides

2019 ◽  
Vol 20 (20) ◽  
pp. 5030 ◽  
Author(s):  
May Aung-Htut ◽  
Craig McIntosh ◽  
Kristin Ham ◽  
Ianthe Pitout ◽  
Loren Flynn ◽  
...  
Keyword(s):  
Antisense Oligonucleotides ◽  
Therapeutic Strategy ◽  
Systematic Approach ◽  
Muscular Atrophy ◽  
Exon Skipping ◽  
Human Genes ◽  
Gene Transcripts ◽  
Primary Gene ◽  
Selection Of

The process of pre-mRNA splicing is a common and fundamental step in the expression of most human genes. Alternative splicing, whereby different splice motifs and sites are recognised in a developmental and/or tissue-specific manner, contributes to genetic plasticity and diversity of gene expression. Redirecting pre-mRNA processing of various genes has now been validated as a viable clinical therapeutic strategy, providing treatments for Duchenne muscular dystrophy (inducing specific exon skipping) and spinal muscular atrophy (promoting exon retention). We have designed and evaluated over 5000 different antisense oligonucleotides to alter splicing of a variety of pre-mRNAs, from the longest known human pre-mRNA to shorter, exon-dense primary gene transcripts. Here, we present our guidelines for designing, evaluating and optimising splice switching antisense oligomers in vitro. These systematic approaches assess several critical factors such as the selection of target splicing motifs, choice of cells, various delivery reagents and crucial aspects of validating assays for the screening of antisense oligonucleotides composed of 2′-O-methyl modified bases on a phosphorothioate backbone.

In vitro evidence for efficacy in food intolerance for the multispecies probiotic formulation Ecologic® Tolerance (Syngut™).

2016 ◽  
Vol 7 (1) ◽  
pp. 111-118 ◽  
Author(s):  
I. Besseling-van der Vaart ◽  
M.D. Heath ◽  
F. Guagnini ◽  
M.F. Kramer
Keyword(s):  
Quality Criteria ◽  
Interleukin 10 ◽  
Food Intolerance ◽  
Bifidobacterium Lactis ◽  
Beneficial Effects ◽  
Specific Effects ◽  
Gut Barrier Function ◽  
Probiotic Strains ◽  
Selection Of

The beneficial effects of probiotics are currently the subject of extensive studies in health and medical research. The aim of this research was to specifically design a new probiotic formulation for supplementation in people suffering from food intolerance. The selection of strains was focussed on the capacity to influence mechanisms of action that are important in development of food intolerance with the following parameters measure: in vitro capacity to produce β-galactosidase, in vitro strengthening of the epithelial barrier, in vitro stimulation of cytokines produced by regulatory T cells, in addition to assessing fundamental quality criteria (stability, gastrointestinal (GI)-survival, multispecies concept, allergen-free). Ecologic®Tolerance/Syngut™ was subsequently developed consisting of a multispecies concept using 4 different probiotic strains (Bifidobacterium lactis W51, Lactobacillus acidophilus W22, Lactobacillus plantarum W21 and Lactococcus lactis W19). Each of these strains demonstrated ability to survive the GI-tract and strain specific effects in producing β-galactosidase, strengthening the gut barrier function after immunological-induced stress and inhibiting Th2 cytokines (IL-4, IL-5 and IL-13 (≥50%), in addition to stimulating interleukin-10 levels; thus, providing in vitro evidence for the efficacy of the selected strains to provide beneficial effects in patients suffering from food intolerance.

Clone selection of in vitro horseradish hairy root cultures

Planta Medica ◽  
2015 ◽  
Vol 81 (16) ◽  
Author(s):  
R Bertóti ◽  
Á Alberti ◽  
A Böszörményi ◽  
R Könye ◽  
T Horváth ◽  
...  
Keyword(s):  
Hairy Root ◽  
Hairy Root Cultures ◽  
Root Cultures ◽  
Clone Selection ◽  
Selection Of

Vibrio harveyi virulence gene expression in vitro and in vivo during infection in black tiger shrimp Penaeus monodon

2020 ◽  
Vol 139 ◽  
pp. 153-160
Author(s):  
S Peeralil ◽  
TC Joseph ◽  
V Murugadas ◽  
PG Akhilnath ◽  
VN Sreejith ◽  
...  
Keyword(s):  
Gene Expression ◽  
Virulence Genes ◽  
Vibrio Harveyi ◽  
Penaeus Monodon ◽  
Challenge Test ◽  
Virulence Gene ◽  
Economic Losses ◽  
Virulence Gene Expression

Luminescent Vibrio harveyi is common in sea and estuarine waters. It produces several virulence factors and negatively affects larval penaeid shrimp in hatcheries, resulting in severe economic losses to shrimp aquaculture. Although V. harveyi is an important pathogen of shrimp, its pathogenicity mechanisms have yet to be completely elucidated. In the present study, isolates of V. harveyi were isolated and characterized from diseased Penaeus monodon postlarvae from hatcheries in Kerala, India, from September to December 2016. All 23 tested isolates were positive for lipase, phospholipase, caseinase, gelatinase and chitinase activity, and 3 of the isolates (MFB32, MFB71 and MFB68) showed potential for significant biofilm formation. Based on the presence of virulence genes, the isolates of V. harveyi were grouped into 6 genotypes, predominated by vhpA+ flaB+ ser+ vhh1- luxR+ vopD- vcrD+ vscN-. One isolate from each genotype was randomly selected for in vivo virulence experiments, and the LD50 ranged from 1.7 ± 0.5 × 103 to 4.1 ± 0.1 × 105 CFU ml-1. The expression of genes during the infection in postlarvae was high in 2 of the isolates (MFB12 and MFB32), consistent with the result of the challenge test. However, in MFB19, even though all genes tested were present, their expression level was very low and likely contributed to its lack of virulence. Because of the significant variation in gene expression, the presence of virulence genes alone cannot be used as a marker for pathogenicity of V. harveyi.

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