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1.
Front Plant Sci ; 15: 1439985, 2024.
Article de Anglais | MEDLINE | ID: mdl-39184574

RÉSUMÉ

Speciation and diversification patterns in angiosperms are frequently shaped by niche evolution. Centaurium Hill is a Mediterranean genus with ca. 25 species, of which 60% are polyploids (tetra- and hexaploids), distributed mainly in the Mediterranean Basin and in areas with temperate and arid climates of Asia, Europe, North-Central Africa and North America. The evolutionary history of this genus has been studied using morphological, biogeographical and molecular approaches, but its climatic niche characterization and its relation with genome evolution (chromosome number and ploidy level) has not been addressed yet. Thus, this study aims to identify the role of the evolution of climatic niche, ploidy level, life cycle and floral traits in the diversification of Centaurium. Climatic niche characterization involved estimating present climate preferences using quantitative data and reconstructing ancestral niches to evaluate climatic niche shifts. The evolution of climatic niche towards selective optima determined by ploidy level (three ploidy levels) and different binary traits (polyploidy, floral size, floral display, herkogamy and life cycle) was addressed under the Ornstein-Uhlenbeck model. Chromosome number evolution was inferred using the ChromoSSE model, testing if changes are clado- or anagenetic. Chromosome number evolution and its link with cladogenesis, life cycle and floral traits was modeled on the phylogeny. The reconstruction of the ancestral niches shows that Centaurium originated in a mild climate and diversified to both humid and cold as well as to dry and warmer climates. Niche conservatism was estimated in the climatic niche of the ancestors, while the climatic niche of the current taxa experienced transitions from their ancestors' niche. Besides, the evolution of climatic niche towards multiple selective optima determined by the studied traits was supported, life cycle optima receiving the highest support. The reconstruction of chromosome number transitions shows that the rate of speciation process resulting from chromosomal changes (chromosomal cladogenesis) is similar to that of non-chromosomal cladogenesis. Additionally, dependent evolution of floral size, floral display and herkogamy with chromosome number variation was supported. In conclusion, polyploidization is a crucial process in the Mediterranean region that assisted speciation and diversification into new areas with different climates, entailing niche shifts and evolution of reproductive strategies.

2.
Ann Bot ; 134(2): 247-262, 2024 Jul 09.
Article de Anglais | MEDLINE | ID: mdl-38687133

RÉSUMÉ

BACKGROUND AND AIMS: Polyploidy is considered one of the main mechanisms of plant evolution and speciation. In the Mediterranean Basin, polyploidy has contributed to making this region a biodiversity hotspot, along with its geological and climatic history and other ecological and biogeographical factors. The Mediterranean genus Centaurium (Gentianaceae) comprises ~25 species, of which 60 % are polyploids, including tetraploids and hexaploids. To date, the evolutionary history of centauries has been studied using Sanger sequencing phylogenies, which have been insufficient to fully understand the phylogenetic relationships in this lineage. The goal of this study is to gain a better understanding of the evolutionary history of Centaurium by exploring the mechanisms that have driven its diversification, specifically hybridization and polyploidy. We aim to identify the parentage of hybrid species, at the species or clade level, as well as assessing whether morphological traits are associated with particular ploidy levels. METHODS: We sequenced RADseq markers from 42 samples of 28 Centaurium taxa, and performed phylogenomic analyses using maximum likelihood, summary coalescent SVDquartets and Neighbor-Net approaches. To identify hybrid taxa, we used PhyloNetworks and the fastSTRUCTURE algorithm. To infer the putative parental species of the allopolyploids, we employed genomic analyses (SNIPloid). The association between different traits and particular ploidy levels was explored with non-metric multidimensional scaling. KEY RESULTS: Our phylogenetic analyses confirmed the long-suspected occurrence of recurrent hybridization. The allopolyploid origin of the tetraploid C. serpentinicola and the hexaploids C. mairei, C. malzacianum and C. centaurioides was also confirmed, unlike that of C. discolor. We inferred additional signatures of hybridization events within the genus and identified morphological traits differentially distributed in different ploidy levels. CONCLUSIONS: This study highlights the important role that hybridization has played in the evolution of a Mediterranean genus such as Centaurium, leading to a polyploid complex, which facilitated its diversification and may exemplify that of other Mediterranean groups.


Sujet(s)
Centaurium , Hybridation génétique , Phylogenèse , Polyploïdie , Centaurium/génétique , Région méditerranéenne , Évolution biologique , Génome végétal
3.
Ann Bot ; 132(5): 949-962, 2023 11 30.
Article de Anglais | MEDLINE | ID: mdl-37738171

RÉSUMÉ

BACKGROUND AND AIMS: Chromosome evolution leads to hybrid dysfunction and recombination patterns and has thus been proposed as a major driver of diversification in all branches of the tree of life, including flowering plants. In this study we used the genus Linum (flax species) to evaluate the effects of chromosomal evolution on diversification rates and on traits that are important for sexual reproduction. Linum is a useful study group because it has considerable reproductive polymorphism (heterostyly) and chromosomal variation (n = 6-36) and a complex pattern of biogeographical distribution. METHODS: We tested several traditional hypotheses of chromosomal evolution. We analysed changes in chromosome number across the phylogenetic tree (ChromEvol model) in combination with diversification rates (ChromoSSE model), biogeographical distribution, heterostyly and habit (ChromePlus model). KEY RESULTS: Chromosome number evolved across the Linum phylogeny from an estimated ancestral chromosome number of n = 9. While there were few apparent incidences of cladogenesis through chromosome evolution, we inferred up to five chromosomal speciation events. Chromosome evolution was not related to heterostyly but did show significant relationships with habit and geographical range. Polyploidy was negatively correlated with perennial habit, as expected from the relative commonness of perennial woodiness and absence of perennial clonality in the genus. The colonization of new areas was linked to genome rearrangements (polyploidy and dysploidy), which could be associated with speciation events during the colonization process. CONCLUSIONS: Chromosome evolution is a key trait in some clades of the Linum phylogeny. Chromosome evolution directly impacts speciation and indirectly influences biogeographical processes and important plant traits.


Sujet(s)
Lin , Linaceae , Phylogenèse , Lin/génétique , Linaceae/génétique , Amélioration des plantes , Polyploïdie , Chromosomes , Évolution moléculaire
4.
J Nephrol ; 35(5): 1449-1456, 2022 06.
Article de Anglais | MEDLINE | ID: mdl-35239175

RÉSUMÉ

BACKGROUND: Although high-volume online hemodiafiltration has been associated with higher clearance and lower pre-dialysis concentration of middle molecular weight toxins compared to hemodialysis, its effect on protein-bound uremic toxins has shown inconclusive results. In this study, we investigated whether hemodiafiltration impacts pre-dialysis plasma levels of the toxins indoxyl sulfate, p-cresyl sulfate, and indole-3-acetic acid compared to high-flux hemodialysis. METHODS: This is a post-hoc analysis of the multicenter, randomized controlled trial HDFit (ClinicalTrials.gov: NCT02787161). Uremic toxins were determined by high performance liquid chromatography at baseline, 3, and 6 months. Mean differences in monthly changes of pre-dialysis uremic toxin concentrations between hemodiafiltration and high-flux hemodialysis were analyzed using linear mixed-effect models. RESULTS: One hundred ninety-three patients (mean age 53 years old, 71% males) were analyzed. There were no differences between groups regarding clinical and biochemical characteristics at baseline or duration of dialysis session and blood flows throughout the follow-up. Mean differences in rates of change (µM/month, [confidence interval CI]) in high-flux hemodialysis vs. hemodiafiltration were 2.4 [0.3 to 4.56], 3.94 [- 1.54 to 9.41] and 0.06 [- 0.6 to 0.5] for indoxyl sulfate, p-cresyl sulfate and indole-3-acetic acid, respectively. In the exploratory analysis, these differences in high-flux hemodialysis vs. hemodiafiltration subgroup with convective volume > 27.5 L were 2.86 [0.43 to 5.28], 7.43 [0.7 to 14.16] and - 0.19 [- 0.88 to 0.50]. CONCLUSION: These exploratory findings suggest that hemodiafiltration is more effective in reducing indoxyl sulfate as compared to standard high-flux hemodialysis, and also that this effect was extended to p-cresyl sulfate in patients achieving higher convective volumes.


Sujet(s)
Hémodiafiltration , Indican , Dialyse , Femelle , Hémodiafiltration/méthodes , Humains , Mâle , Adulte d'âge moyen , Dialyse rénale/effets indésirables , Dialyse rénale/méthodes , Sulfates
5.
Redox Biol ; 20: 367-378, 2019 01.
Article de Anglais | MEDLINE | ID: mdl-30408752

RÉSUMÉ

Manganese(III) porphyrins (MnPs) are superoxide dismutase (SOD) mimics with demonstrated beneficial effects in cancer treatment in combination with chemo- and radiotherapy regimens. Despite the ongoing clinical trials, little is known about the effect of MnPs on metastasis, being therefore essential to understand how MnPs affect this process. In the present work, the impact of the MnP MnTnHex-2-PyP5+ in metastasis-related processes was assessed in breast cancer cells (MCF-7 and MDA-MB-231), alone or in combination with doxorubicin (dox). The co-treatment of cells with non-cytotoxic concentrations of MnP and dox altered intracellular ROS, increasing H2O2. While MnP alone did not modify cell migration, the co-exposure led to a reduction in collective cell migration and chemotaxis. In addition, the MnP reduced the dox-induced increase in random migration of MDA-MB-231 cells. Treatment with either MnP or dox decreased the proteolytic invasion of MDA-MB-231 cells, although the effect was more pronounced upon co-exposure with both compounds. Moreover, to explore the cellular mechanisms underlying the observed effects, cell adhesion, spreading, focal adhesions, and NF-κB activation were also studied. Although differential effects were observed according to the endpoints analysed, overall, the alterations induced by MnP in dox-treated cells were consistent with a therapeutically favorable outcome.


Sujet(s)
Tumeurs du sein/métabolisme , Mouvement cellulaire/effets des médicaments et des substances chimiques , Métalloporphyrines/pharmacologie , Espèces réactives de l'oxygène/métabolisme , Adhérence cellulaire/effets des médicaments et des substances chimiques , Molécules d'adhérence cellulaire/génétique , Molécules d'adhérence cellulaire/métabolisme , Lignée cellulaire tumorale , Survie cellulaire/effets des médicaments et des substances chimiques , Doxorubicine/pharmacologie , Femelle , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Humains , Espace intracellulaire/métabolisme , Métalloporphyrines/composition chimique , Structure moléculaire , Facteur de transcription NF-kappa B/métabolisme
6.
Eur J Pharm Sci ; 81: 1-9, 2016 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-26428697

RÉSUMÉ

The encapsulation of natural ingredients, such as rutin, can offer improvements in sun protection effectiveness. This strategy can provide enhanced flavonoid content and produces an improved bioactive compound with new physical and functional characteristics. As an alternative to common synthetic-based sunscreens, rutin-entrapped gelatin nanoparticles (GNPs) were designed and associated with ethylhexyl dimethyl PABA (EHDP), ethylhexyl methoxycinnamate (EHMC) and methoxydibenzoylmethane (BMDBM) in sunscreen formulations. The purpose of this study was to develop rutin-loaded gelatin nanoparticles and characterize their physicochemical, thermal, functional and safety properties. Rutin-loaded gelatin nanoparticles increased antioxidant activity by 74% relative to free-rutin (FR) solution. Also, this new ingredient upgraded the Sun Protection Factor (SPF) by 48%, indicating its potential as a raw material for bioactive sunscreens. The safety profile indicated that GNPs and glutaraldehyde (GTA) decreased HaCaT cell viability in a concentration/time-dependent manner. However, both blank nanoparticles (B-NC) and rutin-loaded nanoparticles (R-NC) had good performance on skin compatibility tests. These results functionally characterized rutin-loaded nanoparticles as a safe SPF enhancer in sunscreens, especially in association with UV filters.


Sujet(s)
Nanoparticules/administration et posologie , Rutoside/administration et posologie , Produits antisolaires/administration et posologie , Administration par voie cutanée , Alcanes/administration et posologie , Alcanes/composition chimique , Alcanes/pharmacologie , Lignée cellulaire , Survie cellulaire/effets des médicaments et des substances chimiques , Chalcones/administration et posologie , Chalcones/composition chimique , Chalcones/pharmacologie , Cinnamates/administration et posologie , Cinnamates/composition chimique , Cinnamates/pharmacologie , Stabilité de médicament , Femelle , Gélatine/composition chimique , Glutaraldéhyde/administration et posologie , Glutaraldéhyde/composition chimique , Glutaraldéhyde/pharmacologie , Humains , Mâle , Nanoparticules/composition chimique , Tests épicutanés , Propiophénones , Rutoside/composition chimique , Rutoside/pharmacologie , Produits antisolaires/composition chimique , Produits antisolaires/pharmacologie , Rayons ultraviolets , para-Aminobenzoates/administration et posologie , para-Aminobenzoates/composition chimique , para-Aminobenzoates/pharmacologie
7.
Chem Biol Drug Des ; 86(4): 578-88, 2015 Oct.
Article de Anglais | MEDLINE | ID: mdl-25600158

RÉSUMÉ

Multiple mechanisms related to metastases undergo redox regulation. Cu[15]pyN5 is a redox-active copper(II) complex previously studied as a chemotherapy sensitizer in mammary cells. The effects of a cotreatment with Cu[15]pyN5 and doxorubicin (dox) were evaluated in two human breast cancer cell lines: MCF7 (low aggressiveness) and MDA-MB-231 (highly aggressive). Cu[15]pyN5 decreased MCF7-directed cell migration. In addition, a cotreatment with dox and Cu[15]pyN5 reduced the proteolytic invasion of MDA-MB-231 cells. Cell detachment was not affected by exposure to these agents. Cu[15]pyN5 and dox significantly increased intracellular ROS in both cell lines. This increase could be at least partially due to H2 O2 accumulation. The combination of Cu[15]pyN5 with dox may be beneficial in breast cancer treatment as it could help reduce cancer cell migration and invasion. Moreover, the ligand [15]pyN5 has a high affinity for copper(II) and displays potential anti-angiogenic properties. Overall, we present a potential drug that might arrest the progression of breast cancer by different and complementary mechanisms.


Sujet(s)
Antinéoplasiques , Tumeurs du sein/traitement médicamenteux , Mouvement cellulaire/effets des médicaments et des substances chimiques , Cuivre , Espèces réactives de l'oxygène/métabolisme , Antinéoplasiques/composition chimique , Antinéoplasiques/pharmacologie , Tumeurs du sein/métabolisme , Tumeurs du sein/anatomopathologie , Cuivre/composition chimique , Cuivre/pharmacologie , Doxorubicine/composition chimique , Doxorubicine/pharmacologie , Femelle , Humains , Cellules MCF-7
8.
J Antimicrob Chemother ; 64(3): 524-8, 2009 Sep.
Article de Anglais | MEDLINE | ID: mdl-19525516

RÉSUMÉ

OBJECTIVES: To characterize the population structure and resistance mechanisms of Klebsiella pneumoniae isolates that are highly resistant to third-generation cephalosporins, collected from five Spanish hospitals. METHODS: A total of 162 K. pneumoniae isolates from five hospitals located in three geographical areas of Spain were characterized. The number of isolates from each hospital ranged from 3 to 82. The genetic relationship between isolates was established by PFGE and multilocus sequence typing (MLST). bla(ESBL) types and other antibiotic resistance genes were analysed by PCR and sequencing. Plasmids were classified according to their incompatibility group by a PCR-based replicon-typing scheme. RESULTS: All 162 isolates carried the bla(CTX-15) gene. Fifty-eight isolates (35.8%) caused clinical infections and 104 (64.2%) were colonizers. Sixty-nine (42.6%) isolates were collected from newborns and 93 (57.4%) from adults. Using PGFE, the 162 isolates were grouped into seven clusters that were further identified as members of the MLST types 1, 11, 14, 17, 20, 35 and 36. Two hospitals each had two different clones and the remaining three hospitals had a single CTX-M-15-producing K. pneumoniae clone. All clones carried different antibiotic resistance genes, including bla(OXA-1), aac(3)-IIa, aac(6')-Ib-cr, qnrS1 and qnrB. In four of the seven (57.1%) clones the bla(CTX-M-15) gene was transferred by conjugation; in all cases plasmids of the incompatibility group IncF were identified by PCR. CONCLUSIONS: This study shows that multiresistant K. pneumoniae producing CTX-M-15 of MLST types 1, 11, 14, 17, 20, 35 and 36 are spreading as pathogens and colonizers among newborns and adult patients in Spain.


Sujet(s)
Antibactériens/pharmacologie , État de porteur sain/microbiologie , Infections à Klebsiella/microbiologie , Klebsiella pneumoniae/effets des médicaments et des substances chimiques , Klebsiella pneumoniae/enzymologie , bêta-Lactamases/biosynthèse , Adulte , Techniques de typage bactérien , Analyse de regroupements , Infection croisée/microbiologie , Électrophorèse en champ pulsé , Génotype , Hôpitaux , Humains , Nouveau-né , Klebsiella pneumoniae/classification , Klebsiella pneumoniae/isolement et purification , Épidémiologie moléculaire , Plasmides , Réaction de polymérisation en chaîne , Analyse de séquence d'ADN , Espagne
9.
Gac Sanit ; 18(5): 360-5, 2004.
Article de Espagnol | MEDLINE | ID: mdl-15498405

RÉSUMÉ

OBJECTIVES: To describe variations in the management of nasosinus disorders among the Autonomous Communities and hospitals of Spain. METHODS: We analyzed the Minimum Basic Data Set of the public health system from 1998-2000 for the diagnoses of nasosinus polyps and chronic sinusitis. We studied the distribution by regions of the rate of hospitalizations and of 4 indicators of quality of care and efficiency: mean length of stay, percentage of discharges without surgery, percentage of functional endoscopic sinus surgery and surgical complications. A cluster analysis was performed to classify hospitals according to the values of these indicators. RESULTS: We analyzed 13061 discharges from 263 hospitals. Marked differences were found in age-adjusted hospitalization rates by regions. Cluster analysis classified the centers with more than 10 annual discharges in 3 categories: a) 32 hospitals in which the 4 quality indicators were above average; b) 35 hospitals in which 3 of the indicators were below average, and c) 74 hospitals in which 2 indicators were above average and 2 indicators were below average. CONCLUSIONS: Marked interregional variations were found in hospitalization rates, as well as in the characteristics of management of nasosinus disorders in Spanish hospitals. The centers examined could be grouped into three clearly defined patterns according to indicators of quality of care and efficiency.


Sujet(s)
Polypes du nez/chirurgie , Types de pratiques des médecins , Sinusite/chirurgie , Adolescent , Adulte , Sujet âgé , Maladie chronique , Femelle , Hospitalisation , Humains , Mâle , Adulte d'âge moyen , Procédures de chirurgie oto-rhino-laryngologique/statistiques et données numériques , Espagne , Jeune adulte
10.
Gac. sanit. (Barc., Ed. impr.) ; 18(5): 360-365, sept.-oct. 2004. tab
Article de Espagnol | IBECS | ID: ibc-110681

RÉSUMÉ

Objetivo: Describir las variaciones en la asistencia de las enfermedades nasosinusales entre comunidades autónomas (CCAA) y hospitales españoles. Métodos: Se analizó el Conjunto Mínimo Básico de Datos del Sistema Nacional de Salud de los años 1998-2000 para los diagnósticos de pólipos nasosinusales y sinusitis crónica. Se estudió la distribución por CCAA de la tasa de hospitalización y de 4 indicadores de calidad asistencial y eficiencia: estancia media, porcentajes de altas sin intervención, técnicas de cirugía endoscópica nasosinusal y complicaciones posquirúrgicas. Se realizó un análisis de conglomerados para clasificar los hospitales según los valores de dichos indicadores. Resultados: Se analizaron 13.061 altas de 263 hospitales. Se (..) (AU)


Objectives: To describe variations in the management of nasosinus disorders among the Autonomous Communities and hospitals of Spain. Methods: We analyzed the Minimum Basic Data Set of the public health system from 1998-2000 for the diagnoses of nasosinus polyps and chronic sinusitis. We studied the distribution by regions of the rate of hospitalizations and of 4 indicators of quality of care and efficiency: mean length of stay, percentage of discharges without surgery, percentage of functional endoscopic sinus surgery and surgical complications. A cluster analysis was performed to classify hospitals according to the values of these indicators. Results: We analyzed 13061 discharges from 263 hospitals. Marked differences were found in age-adjusted hospitalization rates by regions. Cluster analysis classified the centers with (..) (AU)


Sujet(s)
Humains , Sinusite/épidémiologie , Polypes du nez/épidémiologie , Procédures chirurgicales du nez/statistiques et données numériques , Types de pratiques des médecins , Adénoïdectomie/statistiques et données numériques , Échantillonnage en Grappes , Qualité des soins de santé/tendances , Hospitalisation/statistiques et données numériques , Rendement
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