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Probiotics for maintaining oral health during fixed orthodontic treatment: A systematic review and meta-analysis.
No full textpeer reviewed[en] INTRODUCTION: To systematically review the effect of probiotics on oral health during treatment with fixed orthodontic appliances.
METHODS: PubMed, Embase and the Cochrane Library were searched up to August 2022 using broad MeSH terms and keywords. Randomized clinical trials comparing a probiotic with a control/no treatment; at least 10 patients/group undergoing fixed orthodontic therapy; and reporting at least one oral health-related parameter were included.
RESULTS: The most reported parameters in the 14 included studies were the microbiological counts of mutans streptococci and lactobacilli, microorganisms associated with white spot lesions (WSL). A meta-analysis of these showed a positive effect of probiotics on mutans streptococci. Probiotic treatment led to significantly less patients with high counts and significantly more with low counts of these bacteria. An effect on the lactobacilli counts was not seen. However, the sole clinical study investigating WSL could not demonstrate a clinical effect of probiotics on these lesions. Additionally, one study reported encouraging results of probiotics on bad breath and one on the occurrence of traumatic oral lesions. One study found reduced counts of Porphyromonas gingivalis in the probiotic group. The clinical results of probiotics on plaque index were ambiguous: one study reported that probiotics reduce the plaque and gingival index, and two that probiotics had no significant influence on plaque index.
CONCLUSION: Probiotics are a promising option to lower mutans streptococci counts in patients undergoing fixed orthodontic therapy. However, due to the heterogeneity of the studies, it is not possible to draw conclusions about one specific probiotic
Le « dog whistling » : une technique de communication politique aux enjeux éthiques et démocratiques
No full textLe « dog whistling » est une technique de communication politique subtile reposant sur
l’usage de mots, phrases ou symboles codés qui vont être perçus de manière différente en
fonction des groupes visés. Cette pratique permet aux oratrices et aux orateurs d’adresser des messages spécifiques tout en préservant une apparence de neutralité ou d’innocence. Utilisé dans des contextes divers, le « dog whistling » joue sur l’ambiguïté et la manipulation des discours. Son efficacité repose sur le contournement des sanctions mais aussi dans sa capacité à diviser et polariser la société au détriment du débat démocratique
L’existentialisme de Ian Hacking. À propos d’Ian Hacking, Anthropologie philosophique et raison scientifique, éd. M. Vagelli, Paris, Vrin, 2023
No full texteditorial reviewe
Multitrophic impact of viruses from different realms and hosts on rice health and growth
No full textRice is a major source of food for more than half of the world's population, especially in Asia, and is an important part of the agricultural economy in many countries, providing a source of income for farmers. Firstly, rice viral diseases can lead to a significant decrease in harvest yield. In severe cases, it may even result in total crop failure, posing a threat to global food security.
Rice stripe virus (RSV) is transmitted by the small brown planthopper (SBPH, Laodelphax striatellus Fallen) in a persistent and propagative manner. In this study, RNA-Seq was used to analyze the transcriptomic differences between resistant and susceptible rice varieties at different times post RSV infection. Through Gene Ontology (GO) annotation, differentially expressed genes (DEGs) related to transcription factors, peroxidases, and kinases of 2 varieties at 3 time points were identified. Comparing these 2 varieties, the DEGs associated with these 3 GOs were numerically less in the resistant variety than in the susceptible variety. Eighty-seven DEGs involved in some pathways that have a contribution to disease resistance including plant hormone signal transduction and plant–pathogen interactions were identified. Resistance responses regulated by abscisic acid (ABA) and brassinosteroids (BR) were found to be similar for 2 varieties. Fifty-five DEGs in resistant and susceptible varieties at the 3 time points were identified in both PAMP-triggered immunity (PTI) and effector protein triggered immunity (ETI). These findings will provide valuable information for further research on the interactions between rice and RSV, particularly on molecular mechanisms of rice resistance to RSV infection.
Secondly, phages that infect nitrogen-fixing bacteria can contribute to plant nutrition, thus impacting rice yield and quality. Phages act to regulate soil microbial community structure. Here, low relative abundance of nitrogen-fixing bacteria was found but Enterobacter-infecting phages were highly present in paddy soil where rice plants showed nitrogen deficiency. A novel virulent phage (named here Apdecimavirus NJ2) was identified infecting several species of Enterobacter. It has the morphology of the Autographiviridae family, with a dsDNA genome of 39,605 bp, 47 predicted open reading frames and 52.64 % GC content. Based on comparative genomics and phylogenetic analysis and ICTV demarcation criteria, Apdecimavirus NJ2 could be considered as a novel species in the genus Apdecimavirus, subfamily Studiervirinae. After natural and sterilized field soil were inoculated with this phage, nitrogen-fixing bacteria and phage, respectively, soil nitrogen-fixation capacity and rice growth were impaired abundance of Enterobacter decreased, along with the bacterial community composition and biodiversity changed compared with that of the unadded natural soil control and sterilized soil added with nitrogen-fixing bacteria. Our work provides strong evidence that phages can affect the soil nitrogen cycle by changing the bacterial community. Leveraging phages in the soil could be a useful strategy for improving soil nitrogen fixation
Development of metabolic engineering strategies in Komagataella phaffii for the reduction of cellular methanol requirements based on the cellular response to non-repressive compounds of the pAOX1 promoter
No full textThe methylotrophic yeast Komagataella phaffii (formerly Pichia pastoris) is widely recognized as a prominent platform for recombinant protein (rProt) production. This yeast is capable of oxidizing methanol to support energy production and biomass formation. In this non-conventional yeast, the methanol-regulated pAOX1 promoter has been widely used to drive the expression of recombinant proteins. However, the use of methanol raises significant safety concerns due to its high flammability, particularly in large-scale industrial applications. Consequently, the main objective of this thesis was to explore alternatives to reduce or eliminate the reliance on methanol.
In this framework, disruption of the formate dehydrogenase gene (FDH1) was employed as a strategy to modify the pAOX1 expression system. This genome edition successfully converted the system into a self-inducing platform for rProt synthesis, eliminating the need for methanol or other inducers to trigger gene expression. Further investigation revealed that this induction mechanism is mediated by cytoplasmic formate generated from THF-C1 metabolism, which cannot be converted to carbon dioxide in an FDH1 knockout strain. Notably, this discovery showed that the pAOX1 promoter could be induced under non-repressive conditions, such as in the presence of sorbitol. The efficacy of this system was demonstrated through the synthesis of two model proteins: intracellular eGFP and secreted CalB lipase from Candida antarctica.
Further into this investigation, metabolic engineering efforts focused on optimizing sorbitol uptake to enhance cell growth and rProt production in the FDH1 knockout strain. Sorbitol metabolism was identified as the bottleneck, and overexpression of the sorbitol dehydrogenase gene (SOR1) significantly improved the growth in K. phaffii, leading to a 2.5-fold increase in specific cell growth rate. Despite these improvements, an unexpected impairment in pAOX1 induction was observed. This study proposes several hypotheses to explain this issue, which are discussed in detail in this work.
Overall, this investigation lays the groundwork for a deeper understanding of pAOX1 induction and highlights new avenues for exploring the underlying regulatory mechanisms. These insights will be pivotal in optimizing the system's potential for advancing biotechnological applications in this innovative methanol-free platform
"Perspectives nietzschéennes dans le roman 'sicaresque'. L'exemple de Gustavo Álvarez Gardeazábal."
No full textpeer reviewedLe genre sicaresque, tel que défini par Abad Faciolince, regroupe un ensemble de romans centrés autour du personnage du "sicario", un tueur à gages très présent en Colombie, spécialement dans les années quatre-vingt du XXième siècle. Plusieurs écrivains renommés ont été séduits alors par ce thème, parmi lesquels le lauréat du prix Nobel de littérature Gabriel García Márquez, ainsi que des auteurs toujours actifs aujourd'hui, tels que Fernando Vallejo et Laura Restrepo. Le narcotrafic a également été abordé par des écrivains moins connus sur la scène littéraire internationale mais très présents sur le plan national. Dans cette étude, j'examine la question de la misanthropie chez l'un d'entre eux, à savoir Gustavo Álvarez Gardeazábal, né en 1945 à Tuluá
Seagrass sod transplantation: A relevant tool for preventing the destruction of meadows in coastal construction projects
Full text linkpeer reviewedWe present a successful case of seagrass meadow transplantation on the scale of an industrial project, challenging the long-held belief that these ecosystems are "non-transplantable." Using a sod-based transplantation technique, we relocated 384 m² of Posidonia oceanica meadow from a construction site in 24 days in 2017 to mitigate the environmental impact of reclaiming six hectares of marine land for a new development in Monaco. The eight-year monitoring program (2017–2024) evaluated both structural and physiological parameters of the transplanted seagrass, along with the sediment chemistry in its surrounding environment. Despite nearby maritime construction works during two years, the transplanted meadow showed remarkable resilience, with its health indicators quickly aligning with those of the surrounding natural meadows. Three years after transplantation, the seagrass was flowering in synchrony with the natural meadow and after eight years, its area had expanded beyond the initial transplant, growing by 25,8 % in 2024. This outcome supports salvaging and subsequent transplantation as a viable, ecologically sound alternative to destruction and subsequent compensation measures in coastal development projects. By confirming the effectiveness of careful transplantation techniques, the study underscores that transplantation should be fully considered as a relevant mitigation measure in the Avoid-Mitigate-Compensate sequence.14. Life below wate
Plasmonic Properties of Doped Metal Oxides Investigated through the Kubelka–Munk Formalism
Full text linkpeer reviewedMaterials with broadband tunable optical propertiesare looked for in smart windows applications. Doped metal oxidespresenting dual-band visible (VIS)−near-infrared (NIR) electro-chromic properties can be used for solving such a challenge, andtheir accurate optical characterization is therefore of primeimportance. The Kubelka−Munk model is a state-of-the-art wayto optically quantify the absorption properties of materials and isoccasionally applied to plasmonic materials, even if great careshould be taken to meet the formalism hypotheses. In the presentwork, Kubelka−Munk theory is discussed in the context ofparticles of indium−tin oxide and molybdenum−tungsten oxideformulations that are used as single-NIR and both-VIS/NIR activeadvanced electrochromic materials, respectively. An analytical model is derived for particles of much smaller dimensions than theincident wavelength and is experimentally verified. A dilution method is applied to verify the plasmonic characteristics of theparticles. This study is key for the efficient characterization of the optical properties of metal oxides and plasmonic materials ingeneral, from diffuse reflectance measurements.PLASMON_E