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1.
Sci Data ; 10(1): 7, 2023 01 04.
Article de Anglais | MEDLINE | ID: mdl-36599846

RÉSUMÉ

This paper presents a collection of environmental, geophysical, and other marine-related data for marine ecological models and ecological-niche models. It consists of 2132 raster data for 58 distinct parameters at regional and global scales in the ESRI-GRID ASCII format. Most data originally belonged to open data owned by the authors of this article but residing on heterogeneous repositories with different formats and resolutions. Other data were specifically created for the present publication. The collection includes 565 data with global scale range; 154 at 0.5° resolution and 411 at 0.1° resolution; 196 data with annual temporal aggregation over ~10 key years between 1950 and 2100; 369 data with monthly aggregation at 0.1° resolution from January 2017 to ~May 2021 continuously. Data were also cut out on 8 European marine regions. The collection also includes forecasts for different future scenarios such as the Representative Concentration Pathways 2.6 (63 data), 4.5 (162 data), and 8.5 (162 data), and the A2 scenario of the Intergovernmental Panel on Climate Change (180 data).

2.
Ecol Inform ; 69: 101675, 2022 Jul.
Article de Anglais | MEDLINE | ID: mdl-35615467

RÉSUMÉ

The COVID-19 pandemic has led to reduced anthropogenic pressure on ecosystems in several world areas, but resulting ecosystem responses in these areas have not been investigated. This paper presents an approach to make quick assessments of potential habitat changes in 2020 of eight marine species of commercial importance in the Adriatic Sea. Measurements from floating probes are interpolated through an advection-equation based model. The resulting distributions are then combined with species observations through an ecological niche model to estimate habitat distributions in the past years (2015-2018) at 0.1° spatial resolution. Habitat patterns over 2019 and 2020 are then extracted and explained in terms of specific environmental parameter changes. These changes are finally assessed for their potential dependency on climate change patterns and anthropogenic pressure change due to the pandemic. Our results demonstrate that the combined effect of climate change and the pandemic could have heterogeneous effects on habitat distributions: three species (Squilla mantis, Engraulis encrasicolus, and Solea solea) did not show significant niche distribution change; habitat suitability positively changed for Sepia officinalis, but negatively for Parapenaeus longirostris, due to increased temperature and decreasing dissolved oxygen (in the Adriatic) generally correlated with climate change; the combination of these trends with an average decrease in chlorophyll, probably due to the pandemic, extended the habitat distributions of Merluccius merluccius and Mullus barbatus but reduced Sardina pilchardus distribution. Although our results are based on approximated data and reliable at a macroscopic level, we present a very early insight of modifications that will possibly be observed years after the end of the pandemic when complete data will be available. Our approach is entirely based on Findable, Accessible, Interoperable, and Reusable (FAIR) data and is general enough to be used for other species and areas.

3.
Nanoscale ; 9(19): 6315-6326, 2017 May 18.
Article de Anglais | MEDLINE | ID: mdl-28275767

RÉSUMÉ

Worldwide efforts are currently trying to produce effective risk assessment models for orally ingested nanoparticles. These tests should provide quantitative information on the bioaccessibility and bioavailability of products of biotransformation, such as dissolved ionic species and/or aggregates. In vitro dissolution tests might be useful for nanoparticle risk assessment, because of their potential to quantitatively monitor the changes of specific properties (e.g., dissolution, agglomeration, etc.), which are critical factors linked to bioaccessibility/bioavailability. Unfortunately, the technological advancement of such tools is currently hampered by the complexity and evolving nature of nanoparticle properties that are strongly influenced by the environment and are often difficult to trace in a standardized manner. Hence, the test's success depends on its ability to quantify such properties using standardized experimental conditions to mimic reality as closely as possible. Here we applied an in vitro dissolution test to quantify the dissolution of silver nanoparticles under dynamic conditions, which likely occur in human digestion, providing a clear description of the bioaccessible ionic species (free and matrix bound ions or soluble silver organic or inorganic complexes) occurring during the different digestion phases. We demonstrated the test feasibility using a multi-technique approach and following pre-standardized operational procedures to allow for a comprehensive description of the process as a whole. Moreover, this can favour data reliability for benchmarking. Finally, we showed how the estimated values of the bioaccessible ionic species relate to absorption and excretion parameters, as measured in vivo. The outcomes presented in this work highlight the potential regulatory role of the dissolution test for orally ingested nanoparticles and, although preliminary, experimentally demonstrate the regulatory oriented "read-across" principle.

4.
BMC Evol Biol ; 14: 107, 2014 May 16.
Article de Anglais | MEDLINE | ID: mdl-24885008

RÉSUMÉ

BACKGROUND: Some species of water frogs originated from hybridization between different species. Such hybrid populations have a particular reproduction system called hybridogenesis. In this paper we consider the two species Pelophylax ridibundus and Pelophylax lessonae, and their hybrids Pelophylax esculentus. P. lessonae and P. esculentus form stable complexes (L-E complexes) in which P. esculentus are hemiclonal. In L-E complexes all the transmitted genomes by P. esculentus carry deleterious mutations which are lethal in homozygosity. RESULTS: We analyze, by means of an individual based computational model, L-E complexes. The results of simulations based on the model show that, by eliminating deleterious mutations, L-E complexes collapse. In addition, simulations show that particular female preferences can contribute to the diffusion of deleterious mutations among all P. esculentus frogs. Finally, simulations show how L-E complexes react to the introduction of translocated P. ridibundus. CONCLUSIONS: The conclusions are the following: (i) deleterious mutations (combined with sexual preferences) strongly contribute to the stability of L-E complexes; (ii) female sexual choice can contribute to the diffusion of deleterious mutations; and (iii) the introduction of P. ridibundus can destabilize L-E complexes.


Sujet(s)
Hybridation génétique , Mutation , Ranidae/génétique , Animaux , Femelle , Aptitude génétique , Génétique des populations , Mâle , Modèles biologiques , Ranidae/classification , Ranidae/physiologie
5.
Appl Microbiol Biotechnol ; 96(2): 431-41, 2012 Oct.
Article de Anglais | MEDLINE | ID: mdl-22573266

RÉSUMÉ

In this study, the probiotic potential of Lactobacillus plantarum wild-type and derivative mutant strains was investigated. Bacterial survival was evaluated in an in vitro system, simulating the transit along the human oro-gastro-intestinal tract. Interaction with human gut epithelial cells was studied by assessing bacterial adhesive ability to Caco-2 cells and induction of genes involved in innate immunity. L. plantarum strains were resistant to the combined stress at the various steps of the simulated gastrointestinal tract. Major decreases in the viability of L. plantarum cells were observed mainly under drastic acidic conditions (pH ≤ 2.0) of the gastric compartment. Abiotic stresses associated to small intestine poorly affected bacterial viability. All the bacterial strains significantly adhered to Caco-2 cells, with the ΔctsR mutant strain exhibiting the highest adhesion. Induction of immune-related genes resulted higher upon incubation with heat-inactivated bacteria rather than with live ones. For specific genes, a differential transcriptional pattern was observed upon stimulation with different L. plantarum strains, evidencing a possible role of the knocked out bacterial genes in the modulation of host cell response. In particular, cells from Δhsp18.55 and ΔftsH mutants strongly triggered immune defence genes. Our study highlights the relevance of microbial genetic background in host-probiotic interaction and might contribute to identify candidate bacterial genes and molecules involved in probiosis.


Sujet(s)
Lactobacillus plantarum/génétique , Mutation , Probiotiques/métabolisme , Adhérence bactérienne , Cellules Caco-2 , Cytokines/génétique , Cytokines/immunologie , Cellules épithéliales/immunologie , Cellules épithéliales/microbiologie , Tube digestif/immunologie , Tube digestif/microbiologie , Humains , Lactobacillus plantarum/croissance et développement , Lactobacillus plantarum/physiologie , Viabilité microbienne , Modèles biologiques
6.
Microbiol Res ; 167(4): 187-93, 2012 Apr 20.
Article de Anglais | MEDLINE | ID: mdl-21795030

RÉSUMÉ

FtsH proteins are ubiquitous membrane-bound, ATP-dependent metalloproteases of the AAA family. In eubacteria, FtsH is involved in protein quality control under stress conditions. Lactobacillus plantarum is a widespread lactic acid bacterium that is encountered in several fermented food, including dairy products, vegetables and meat. In the present work the expression of the ftsH gene of L. plantarum was studied by quantitative real time RT-PCR in bacterial cultures subjected to various abiotic stresses. Both oxidative stress and addition of a membrane-fluidizing agent induced ftsH transcription, while a depletion of carbon-source repressed its mRNA level. Mutants deprived of the FtsH protease exhibited remarkable sensitivity to elevated temperature and increased salt concentration; conversely, overexpression of ftsH resulted in increased thermotolerance and resistance to salt. FtsH mutant had a reduced capacity to form biofilms on abiotic surfaces and exhibited different cell surface physico-chemical properties with respect to the wild type strain.


Sujet(s)
ATP-dependent proteases/métabolisme , Protéines bactériennes/métabolisme , Biofilms/croissance et développement , Délétion de gène , Lactobacillus plantarum/physiologie , Stress physiologique , Propriétés de surface , ATP-dependent proteases/génétique , Protéines bactériennes/génétique , Biofilms/effets des médicaments et des substances chimiques , Biofilms/effets des radiations , Analyse de profil d'expression de gènes , Lactobacillus plantarum/effets des médicaments et des substances chimiques , Lactobacillus plantarum/génétique , Lactobacillus plantarum/effets des radiations , Réaction de polymérisation en chaine en temps réel , RT-PCR , Sels/toxicité , Température
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