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Plant-herbivore assemblages under natural conditions are driven by plant size,not chemical defenses

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Journal of Plant Ecology 2017年第6期10卷 1012-1021页

作者： Eva Castells Maria Morante sandra saura-mas Anabel Blasco-Moreno Departament de Farmacologia Terapèutica i ToxicologiaUniversitat Autònoma de BarcelonaCerdanyola del Vallès 08193Spain CREAF Cerdanyola del Vallès 08193Spain Department de Biologia Animal Vegetal i EcologiaUniversitat Autònoma de BarcelonaCerdanyola del Vallès 08193Spain Servei d’Estadística Aplicada Universitat Autònoma de BarcelonaCerdanyola del Vallès 08193Spain

Aims Plant secondary metabolites have been traditionally recognized as key traits regulating plant-herbivore assemblages.However,the ecological relevance of secondary metabolites as resistance mecha-nisms in comparison to other plant attributes,including physical,morphological or ecological traits,has been recently questioned.We aim to evaluate the role of chemical defenses,plant size and the presence of insect competitors on driving the differences in her-bivory damage under natural conditions.Methods We performed a replicated field study on the herbivore commu-nity associated with four Senecio species(S.lividus,S.vulgaris,S.inaequidens and S.pterophorus)during a full-reproductive season in Montseny Natural Park(catalonia,NE Spain).Pyrrolizidine alka-loids(PAs),the most characteristic chemical defenses of Senecio due to their toxic effects on herbivores,were analyzed by gas chro-matography.Individual plant size was estimated by the number of flower heads produced over the entire reproductive season.We used linear mixed models to explore the relationships between total PA concentrations,plant size and herbivory levels.Important Findings PA concentrations were not related to the natural guild of herbivores within any plant species or insect type.Moreover,no significant interactions were found between insect species sharing the same host plants.In contrast,herbivore abundance was positively related to plant size in S.vulgaris,S.lividus and S.inaequidens.We found no evidence that PAs confer an increased plant resistance against herbivores in Senecio.Our study supports the hypothesis that plant chemical defenses have a secondary role in determining plant-her-bivore assemblages in comparison to other plant traits under the complexity of natural conditions.

关键词： Senecio herbivory chemical defenses pyrrolizidine alkaloids plant traits

The importance of functional diversity in the stability of Mediterranean shrubland communities after the impact of extreme climatic events

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Journal of Plant Ecology 2017年第2期10卷 281-293页

作者： Enrique Gde la Riva Francisco Lloret Ignacio MPérez-Ramos Teodoro Marañón sandra saura-mas Ricardo Díaz-Delgado Rafael Villar Area de Ecología Facultad de CienciasUniversidad de Cordoba.14071 CordobaSpain CREAF Cerdanyola del Vallés08193 BarcelonaSpain Unitat d’Ecologia Dept.Biologia AnimalBiologia Vegetal i EcologiaUniversitat Autònoma BarcelonaEdifici CCampus UAB08193Cerdanyola del VallèsBarcelonaSpain IRNAS CSICAv.Reina Mercedes 10PO Box 1052.41080 SevillaSpain Estación Biológica de Doñana CSIC.c/Americo Vespucios/nIsla de la Cartuja.41092 SevillaSpain

Aims Extreme climatic events may have important consequences for plant community structure and composition.in 2005,a severe drought together with a cold winter promoted extensive damage and mortal-ity in shrubland communities of southwest Spain(Doñana National Park).Here,we aim to identify the mechanisms underlying commu-nity stability(resistance and resilience)in response to this extreme climatic event,considering changes in the functional structure of these communities.Methods We used a trait-based approach,quantifying variations in 10 func-tional traits at the community level(community weighted means,CWM)and the functional diversity(functional richness,evenness and divergence)in 18 plots at three different times:predating the climatic event(estimated from the sum of the live and dead volume of each species in 2007),and 2 and 8 years after the 2005 episode.We also quantified the differences in functional traits and functional diversity between adult and recruit stages,which allowed us to bet-ter understand the contribution of the recruitment to the mainte-nance of the functional structure and diversity of the community.Important Findings Communities with higher functional divergence before the cli-matic event maintained nearly constant their levels of functional divergence 8 years after,but they were more prone to changes in species composition.Community resistance in terms of vegeta-tion cover was positively correlated with root dry matter content,whereas community resilience was positively correlated with leaf chlorophyll(LChl).We also found that some values(weighted means)of functional community traits(such as root dry matter con-tent and LChl)had increased 2 years after the event,returning to the pre-event conditions after 8 years.in addition,there was hardly any establishment of new species in the community and the recruits did not make substantial differences to the community functional structure.Only seed mass differed significantly between the adult and seedling stages.in summary,the extreme climatic ev

关键词： climate change Doñana drought functional trait recruitment resilience resistance

New environmental factors related to diabetes risk in humans:Emerging bisphenols used in synthesis of plastics

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World Journal of Diabetes 2023年第8期14卷 1301-1313页

作者： Rafael Moreno-Gómez-Toledano María Delgado-Marín Alberto Cook-Calvete Claudia González-Cucharero Nunzio Alcharani Beatriz Jiménez-Guirado Ignacio Hernandez Rafael Ramirez-Carracedo Laura Tesoro Laura Botana sandra Sánchez-Esteban Javier Diez-Mata Jose Luis Zamorano Ricardo J.Bosch Carlos Zaragoza Marta saura Universidad de Alcalá Department of Biological Systems/PhysiologyAlcaláde Henares 28871Spain Cardiology Department University Hospital Ramón y CajalMadrid 28034Spain Laboratory of Cardiovascular Pathophysiology Joint Translational Research UnitUniversity Francisco de Vitoria School of MedicineMadrid 28034Spain Instituto Ramón y Cajal de Investigación Sanitaria-IRYCIS Madrid 28034Spain

BACKGROUND Diabetes mellitus(DM)is one of the largest global health emergencies of the 21st century.In recent years,its connection with environmental pollutants,such as bisphenol A(BPA),has been demonstrated;consequently,new structurally similar molecules are used to replace BPA in the plastics industry(BPS,BPF and BPAF).AIM To carry out a systematic review to allow coherent evaluation of the state of the art.Subsequently,a meta-analysis was performed to unify the existing quantitative data.METHODS Firstly,a systematic review was carried out,using the terms“(bisphenol)AND(Diabetes OR Hyperglycemia)”,to maximize the number of results.Subsequently,three authors analyzed the set of articles.Finally,a meta-analysis was performed for each BP,using RevMan software.In addition,funnel plots were developed to study publication bias.RESULTS The systematic analysis of the literature revealed 13 recent articles(2017–2023)related to the study paradigm.The qualitative analysis showed interesting data linking diabetes to the three most widely used substitute BPs in the industry:BPS,BPF and BPAF.Finally,the meta-analysis determined a positive relationship with BPS,BPF and BPAF,which was only statistically significant with BPS.CONCLUSION There is a need to apply the precautionary principle,regulating the use of new BPs.Therefore,replacing BPA with BPS,BPF or BPAF is unlikely to protect the population from potential health risks,such as DM.

关键词： Bisphenol S Bisphenol F Bisphenol AF Diabetes mellitus Systematic review Meta-analysis

Pigmented well-differentiated hepatocellular neoplasm with β-catenin mutation

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Hepatobiliary & Pancreatic Diseases International 2015年第6期14卷 660-664页

作者： Lara Neves Souza Rodrigo Bronze de Martino Richard Thompson sandra Strautnieks Nigel D Heaton Alberto Quaglia Institute of Liver Studies King's College Hospital Department of Gastroenterology Discipline of Liver and Gastrointestinal TransplantationHospital das ClínicasUniversity of S?o Paulo

ABSTRACT： According to the most recent WHO classification of hepatocellular adenomas, a small percentage of inflammatory hepatocellular adenomas presents with mutation in the β-catenin gene and are at higher risk of malignant transformation. It has been recognized that adenoma-like hepatocellular neoplasms with focal atypia, or in unusual clinical context present with similar cytogenetic and immunohistochemistry characteristics to well-differentiated hepatocellular carcino- mas.

关键词： hepatocellular adenoma hepatocellular carcinoma β-catenin glutamine synthetase diethylstilbestrol