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1.
Cereb Cortex ; 33(6): 2748-2760, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35753703

RESUMEN

The investigation of resting-state functional connectivity (rsFC) in asymptomatic individuals at genetic risk for Alzheimer's disease (AD) enables discovering the earliest brain alterations in preclinical stages of the disease. The APOE-ε4 variant is the major genetic risk factor for AD, and previous studies have reported rsFC abnormalities in carriers of the ε4 allele. Yet, no study has assessed APOE-ε4 gene-dose effects on rsFC measures, and only a few studies included measures of cognitive performance to aid a clinical interpretation. We assessed the impact of APOE-ε4 on rsFC in a sample of 429 cognitively unimpaired individuals hosting a high number of ε4 homozygotes (n = 58), which enabled testing different models of genetic penetrance. We used independent component analysis and found a reduced rsFC as a function of the APOE-ε4 allelic load in the temporal default-mode and the medial temporal networks, while recessive effects were found in the extrastriate and limbic networks. Some of these results were replicated in a subsample with negative amyloid markers. Interaction with cognitive data suggests that such a network reorganization may support cognitive performance in the ε4-homozygotes. Our data indicate that APOE-ε4 shapes the functional architecture of the resting brain and favor the idea of a network-based functional compensation.


Asunto(s)
Enfermedad de Alzheimer , Apolipoproteína E4 , Mapeo Encefálico , Encéfalo , Cognición , Red Nerviosa , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico/métodos , Cognición/fisiología , Predisposición Genética a la Enfermedad/genética , Genotipo , Imagen por Resonancia Magnética , Red Nerviosa/fisiología , Vías Nerviosas/fisiología
2.
Int J Mol Sci ; 25(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38338673

RESUMEN

Metabolic bone diseases cover a broad spectrum of disorders that share alterations in bone metabolism that lead to a defective skeleton, which is associated with increasing morbidity, disability, and mortality. There is a close connection between the etiology of metabolic bone diseases and genetic factors, with TP53 being one of the genes associated therewith. The single nucleotide polymorphism (SNP) Arg72Pro of TP53 is a genetic factor associated with several pathologies, including cancer, stroke, and osteoporosis. Here, we aim to analyze the influence of the TP53 Arg72Pro SNP on bone mass in humanized Tp53 Arg72Pro knock-in mice. This work reports on the influence of the TP53 Arg72Pro polymorphism in bone microarchitecture, OPG expression, and apoptosis bone status. The results show that the proline variant of the TP53 Arg72Pro polymorphism (Pro72-p53) is associated with deteriorated bone tissue, lower OPG/RANK ratio, and lower apoptosis in bone tissue. In conclusion, the TP53 Arg72Pro polymorphism modulates bone microarchitecture and may be a genetic biomarker that can be used to identify individuals with an increased risk of suffering metabolic bone alterations.


Asunto(s)
Enfermedades Óseas Metabólicas , Proteína p53 Supresora de Tumor , Animales , Ratones , Biomarcadores , Huesos , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Proteína p53 Supresora de Tumor/genética , Humanos
3.
Ecol Lett ; 25(2): 264-277, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34971487

RESUMEN

Mutualism effectiveness, the contribution of an interacting organism to its partner's fitness, is defined as the number of immediate outcomes of the interactions (quantity component) multiplied by the probability that an immediate outcome results in a new individual (quality component). These components form a two-dimensional effectiveness landscape with each species' location determined by its values of quantity (x-axis) and quality (y-axis). We propose that the evolutionary history of mutualistic interactions leaves a footprint that can be identified by three properties of the spatial structure of effectiveness values: dispersion of effectiveness values, relative contribution of each component to the effectiveness values and correlation between effectiveness components. We illustrate this approach using a large dataset on synzoochory, seed dispersal by seed-caching animals. The synzoochory landscape was clumped, with effectiveness determined primarily by the quality component, and with quantity and quality positively correlated. We suggest this type of landscape structure is common in generalised coevolved mutualisms, where multiple functionally equivalent, high-quality partners exert similarly strong selection. Presumably, only those organisms located in high-quality regions will impact the evolution of their partner. Exploring properties of effectiveness landscapes in other mutualisms will provide new insight into the evolutionary and ecological consequences of mutualisms.


Asunto(s)
Simbiosis , Animales
4.
Nature ; 538(7624): 233-237, 2016 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-27680701

RESUMEN

The psychological, sociological and evolutionary roots of conspecific violence in humans are still debated, despite attracting the attention of intellectuals for over two millennia. Here we propose a conceptual approach towards understanding these roots based on the assumption that aggression in mammals, including humans, has a significant phylogenetic component. By compiling sources of mortality from a comprehensive sample of mammals, we assessed the percentage of deaths due to conspecifics and, using phylogenetic comparative tools, predicted this value for humans. The proportion of human deaths phylogenetically predicted to be caused by interpersonal violence stood at 2%. This value was similar to the one phylogenetically inferred for the evolutionary ancestor of primates and apes, indicating that a certain level of lethal violence arises owing to our position within the phylogeny of mammals. It was also similar to the percentage seen in prehistoric bands and tribes, indicating that we were as lethally violent then as common mammalian evolutionary history would predict. However, the level of lethal violence has changed through human history and can be associated with changes in the socio-political organization of human populations. Our study provides a detailed phylogenetic and historical context against which to compare levels of lethal violence observed throughout our history.


Asunto(s)
Evolución Cultural/historia , Homicidio/historia , Homicidio/psicología , Mamíferos/psicología , Filogenia , Violencia/historia , Violencia/psicología , Agresión/psicología , Animales , Muerte , Historia del Siglo XVII , Historia Antigua , Humanos , Lactante , Infanticidio/historia , Infanticidio/psicología , Masculino , Política , Primates/psicología
5.
Int J Mol Sci ; 23(6)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35328654

RESUMEN

Bone is crucial for the support of muscles and the protection of vital organs, and as a reservoir of calcium and phosphorus. Bone is one of the most metabolically active tissues and is continuously renewed to adapt to the changes required for healthy functioning. To maintain normal cellular and physiological bone functions sufficient oxygen is required, as evidence has shown that hypoxia may influence bone health. In this scenario, this review aimed to analyze the molecular mechanisms involved in hypoxia-induced bone remodeling alterations and their possible clinical consequences. Hypoxia has been associated with reduced bone formation and reduced osteoblast matrix mineralization due to the hypoxia environment inhibiting osteoblast differentiation. A hypoxic environment is involved with increased osteoclastogenesis and increased bone resorptive capacity of the osteoclasts. Clinical studies, although with contradictory results, have shown that hypoxia can modify bone remodeling.


Asunto(s)
Remodelación Ósea , Osteoclastos , Diferenciación Celular , Humanos , Hipoxia , Osteoblastos , Osteoclastos/fisiología , Osteogénesis/fisiología
6.
Proc Biol Sci ; 288(1955): 20211080, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34284635

RESUMEN

Mammals kill both conspecific infants and adults. Whereas infanticide has been profusely studied, the killing of non-infants (adulticide) has seldom attracted the attention of researchers. Mammals kill conspecific adults by at least four, non-exclusive reasons: during intrasexual aggression for mating opportunities, to defend valuable resources, to protect their progeny and to prey upon conspecifics. In this study, we test which reason is most likely to explain male and female adulticide in mammals. For this, we recorded the presence of adulticide, the ecological and behavioural traits, and the phylogenetic relationship for more than 1000 species. Adulticide has been recorded in over 350 species from the most important Mammalian clades. Male adulticide was phylogenetically correlated with the presence of size dimorphism and intrasexually selected weapons. Female adulticide was phylogenetically associated with the occurrence of infanticide. These results indicate that the evolutionary pathways underlying the evolution of adulticide differ between sexes in mammals. Whereas males commit adulticide to increase breeding opportunities and to compete with other males for mating, females commit adulticide mainly to defend offspring from infanticidal conspecifics.


Asunto(s)
Agresión , Mamíferos , Animales , Femenino , Humanos , Masculino , Filogenia , Reproducción
7.
Water Sci Technol ; 82(6): 1044-1061, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33055395

RESUMEN

This study evaluates the feasibility of advanced biofilm microalgae cultivation in a twin layer (TL) system for nutrient removal (N and P) as the tertiary treatment in small wastewater treatment plants (WWTPs) located in sensitive areas. Furthermore, the potential valorisation of microalgae biomass as a component of bio-based fertilizers is assessed. Scenedesmus sp. was chosen among 33 microalgae strains for inoculation of TL due to its high growth rate and its nutrient uptake capacity. The tests carried out in the prototype were markedly efficient for total soluble and ammoniacal nitrogen removal (up to 66 and 94%, respectively). In terms of potential valorisation of microalgae, the nutrient content was 5.5% N (over 40% protein), 8.8% P2O5 and 1.5% K2O, high enzymatic activity, very low levels of heavy metals and no detectable pathogen presence. However, in the formulation of solid-state bio-based fertilizers, the microalgae proportions in blends of over 2% of microalgae led to negative effects on ryegrass (Lolium perenne L. ssp.) and barley (Hordeum vulgare ssp.). The obtained results demonstrate that TL represents a promising technology, which allows efficient tertiary treatment of urban wastewater and the production of high-quality bio-based fertilizer.


Asunto(s)
Microalgas , Scenedesmus , Biomasa , Nutrientes , Aguas Residuales
8.
New Phytol ; 223(1): 354-365, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30761538

RESUMEN

The pollination effectiveness of a flower visitor has traditionally been measured as the product of a quantity component that depends on the frequency of interaction and a quality component that measures the per-visit effects on plant reproduction. We propose that this could be complemented with a genetic component informing about each pollinator's contribution to the genetic diversity and composition of the plant progeny. We measured the quantity and quality components of effectiveness of most pollinator functional groups of the generalist herb Erysimum mediohispanicum. We used 10 microsatellite markers to calculate the genetic component as the diversity of sires among siblings and included it into the calculation of the pollination effectiveness. Functional groups varied in the quantity and quality components, which were shown to be decoupled. Functional groups also differed in the genetic component. This component changed the estimates of pollination effectiveness, increasing the differences between some functional groups and modifying the pollination effectiveness landscape. We demonstrate that including the genetic component in the calculation of the pollination effectiveness may allow a more complete quantification of the contribution of each pollinator to the reproductive success of a plant, providing information on its mating patterns and long-term fitness.


Asunto(s)
Erysimum/genética , Erysimum/fisiología , Polinización/genética , Animales , Insectos/fisiología
9.
Ecol Lett ; 20(5): 577-590, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28349589

RESUMEN

A core interest in studies of mutualistic interactions is the 'effectiveness' of mutualists in providing benefits to their partners. In plant-animal mutualisms it is widely accepted that the total effect of a mutualist on its partner is estimated as (1) a 'quantity' component multiplied by (2) a 'quality' component, although the meanings of 'effectiveness,' 'quantity,' and 'quality' and which terms are applied to these metrics vary greatly across studies. In addition, a similar quantity × quality = total effect approach has not been applied to other types of mutualisms, although it could be informative. Lastly, when a total effect approach has been applied, it has invariably been from a phytocentric perspective, focussing on the effects of animal mutualists on their plant partner. This lack of a common framework of 'effectiveness' of mutualistic interactions limits generalisation and the development of a broader understanding of the ecology and evolution of mutualisms. In this paper, we propose a general framework and demonstrate its utility by applying it to both partners in five different types of mutualisms: pollination, seed dispersal, plant protection, rhizobial, and mycorrhizal mutualisms. We then briefly discuss the flexibility of the framework, potential limitations, and relationship to other approaches.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Hongos/fisiología , Modelos Teóricos , Fenómenos Fisiológicos de las Plantas , Simbiosis , Animales , Micorrizas , Polinización , Dispersión de Semillas
10.
Proc Natl Acad Sci U S A ; 110(19): 7738-41, 2013 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-23610389

RESUMEN

Most emerging infectious diseases (EIDs) in humans have arisen from animals. Identifying high-risk hosts is therefore vital for the control and surveillance of these diseases. Viewing hosts as connected through the parasites they share, we use network tools to investigate predictors of parasitism and sources of future EIDs. We generated host-parasite networks that link hosts when they share a parasite, using nonhuman primates as a model system because--owing to their phylogenetic proximity and ecological overlap with humans--they are an important source of EIDs to humans. We then tested whether centrality in the network of host species--a measurement of the importance of a given node (i.e., host species) in the network--is associated with that host serving as a potential EID source. We found that centrality covaries with key predictors of parasitism, such as population density and geographic range size. Importantly, we also found that primate species having higher values of centrality in the primate-parasite network harbored more parasites identified as EIDs in humans and had parasite communities more similar to those found in humans. These relationships were robust to the use of different centrality metrics and to multiple ways of controlling for variation in how well each species has been studied (i.e., sampling effort). Centrality may therefore estimate the role of a host as a source of EIDs to humans in other multispecific host-parasite networks.


Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Parasitarias en Animales/transmisión , Primates/parasitología , Algoritmos , Animales , Biodiversidad , Control de Enfermedades Transmisibles , Enfermedades Transmisibles Emergentes/genética , Bases de Datos Factuales , Geografía , Humanos , Modelos Biológicos , Análisis Multivariante , Parásitos , Densidad de Población , Primates/genética
12.
New Phytol ; 205(1): 440-53, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25252267

RESUMEN

It is widely assumed that floral diversification occurs by adaptive shifts between pollination niches. In contrast to specialized flowers, identifying pollination niches of generalist flowers is a challenge. Consequently, how generalist pollination niches evolve is largely unknown. We apply tools from network theory and comparative methods to investigate the evolution of pollination niches among generalist species belonging to the genus Erysimum. These species have similar flowers. We found that the studied species may be grouped in several multidimensional niches separated not by a shift of pollinators, but instead by quantitative variation in the relative abundance of pollinator functional groups. These pollination niches did not vary in generalization degree; we did not find any evolutionary trend toward specialization within the studied clade. Furthermore, the evolution of pollination niche fitted to a Brownian motion model without phylogenetic signal, and was characterized by frequent events of niche convergences and divergences. We presume that the evolution of Erysimum pollination niches has occurred mostly by recurrent shifts between slightly different generalized pollinator assemblages varying spatially as a mosaic and without any change in specialization degree. Most changes in pollination niches do not prompt floral divergence, a reason why adaptation to pollinators is uncommon in generalist plants.


Asunto(s)
Evolución Biológica , Erysimum/fisiología , Polinización/fisiología , Animales , Biodiversidad , Flores/fisiología , Insectos/fisiología , Funciones de Verosimilitud
13.
Biol Lett ; 10(1): 20131000, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24402718

RESUMEN

In recent years, the analysis of interaction networks has grown popular as a framework to explore ecological processes and the relationships between community structure and its functioning. The field has rapidly grown from its infancy to a vibrant youth, as reflected in the variety and quality of the discussions held at the first international symposium on Ecological Networks in Coimbra-Portugal (23-25 October 2013). The meeting gathered 170 scientists from 22 countries, who presented data from a broad geographical range, and covering all stages of network analyses, from sampling strategies to effective ways of communicating results, presenting new analytical tools, incorporation of temporal and spatial dynamics, new applications and visualization tools.(1) During the meeting it became evident that while many of the caveats diagnosed in early network studies are successfully being tackled, new challenges arise, attesting to the health of the discipline.


Asunto(s)
Biodiversidad , Ecología , Portugal
14.
Environ Sci Pollut Res Int ; 31(47): 57748-57764, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39292305

RESUMEN

Gallium and indium, metals present in light-emitting diode (LED) lighting technology, can be effectively recovered from aqueous solutions by sorption. For this purpose, carbonaceous materials, such as activated carbon, or low-cost biosorbents as beer bagasse, spent coffee grounds or peanut shells, and a low-cost zeolite as chabazite, were characterized by BET, FTIR, XRD, and SEM analysis prior use. Protonated chabazite, with high surface area (505 m2/g) and a Si/Al molar ratio of 3.4, showed high sorption capacities for gallium (56 mg/g) and indium (92 mg/g), which is 10 to 30 times higher than those of our carbonaceous materials (T = 298 K, pH < 3, dosage = 1 g/L). Sorption experiments with both metals in solution showed a competitive effect between gallium and indium for the sorption sites of the chabazite, showing more affinity toward gallium than indium. Ga3+sorbed/In3+sorbed molar ratio above 2 was achieved for the same initial concentration of both metals, increasing to almost 3 when the initial gallium concentration increased, which was appropriate since gallium concentration tends to be higher in LED chips. However, the sorption capacity for both metals was always around 0.35 mmol Ga + In/g. The selectivity of the chabazite was conditioned by different behavior of both metals in aqueous solution at the sorption pH (below 3.5) being the predominant species in solution Ga(OH)2+ for gallium and In3+ for indium. Sorption with protonated chabazite can be used in the treatment of spent LEDs leachate for the dual purpose of water purification and selective metal separation.


Asunto(s)
Galio , Indio , Indio/química , Galio/química , Adsorción , Contaminantes Químicos del Agua/química , Metales/química , Zeolitas/química
15.
Evol Lett ; 8(4): 610-621, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39100232

RESUMEN

Adaptive phenotypic plasticity evolves in response to the contrasting selection pressures that arise when organisms face environmental heterogeneity. Despite its importance for understanding how organisms successfully cope with environmental change, adaptive plasticity is often assumed but rarely demonstrated. We study here the adaptive nature of the extreme seasonal within-individual floral polyphenism exhibited by the crucifer Moricandia arvensis, a Mediterranean species that produces two different types of flowers depending on the season of the year. During spring, this species has large, cross-shaped, lilac flowers, while during summer, it develops small, rounded, white flowers. Although floral polyphenism was associated with increased plant fitness, selection moved floral traits away from their local optimum values during the harsh summer. This result strongly suggests that floral polyphenism is not adaptive in M. arvensis. The main factor selecting against floral polyphenism was pollinators, as they select for the same floral morph in all environments. Despite not being adaptive, floral polyphenism occurs throughout the entire distribution range of M. arvensis and has probably been present since the origin of the species. To solve this paradox, we explored the factors causing floral polyphenism, finding that floral polyphenism was triggered by summer flowering. Summer flowering was beneficial because it led to extra seed production and was favored by adaptive plasticity in leaf functional traits. Taken together, our study reveals a complex scenario in which nonadaptive floral polyphenism has been indirectly maintained over M. arvensis evolutionary history by selection operating to favor summer flowering. Our study provides thus strong evidence that nonadaptive plasticity may evolve as a byproduct of colonizing stressful environments.

16.
Ecology ; 104(4): e3995, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36805556

RESUMEN

The outcome of many ecological interactions lies somewhere along a continuum between pure positive and pure negative effects. Although the popularity of this idea has notoriously risen in the last decades, with the occurrence of continua in interaction outcomes invoked for a wide variety of interactions, the absence of a precise theoretical treatment has led to considerable inaccuracy and ambiguity in its treatment. We develop here a consumer-resource model to explore the occurrence of continua. This model is based on the assumption that the distribution of individual interaction events includes both negative and positive immediate outcomes, with variable frequencies, for at least one of the interacting species. Our study shows that continua in interaction outcomes happen just by varying the sign and impact of individual events. The exact shape of the continua depends on the proportion of positive versus negative events and the relative magnitude of per-capita interaction strengths. Our model shows that continua in interaction outcomes are a key property of most pairwise interactions and are originated from the variable roles played by the interacting partners. It constitutes a step forward in the paradigm change from discrete categorization of ecological interactions to a new perspective over a continuous space.

17.
Sci Rep ; 13(1): 7944, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37193716

RESUMEN

A main concern of agriculture is to improve plant nutrient efficiency to enhance crop yield and quality, and at the same time to decrease the environmental impact caused by the lixiviation of excess N fertilizer application. The aim of this study was to evaluate the potential use of biopolymers (BPs), obtained by alkaline hydrolysis of the solid anaerobic digestate of municipal biowastes, in order to face up these main concerns of agriculture. The experimental trials involved the application of BPs (at 50 and 150 kg/ha) alone or mixed with different amounts (100%, 60% and 0%) of mineral fertilizer (MF). Three different controls were routinely included in the experimental trials (MF 100%, 60% and 0%). The effect of BPs on lettuce was evaluated by monitoring growth parameters (fresh and dry weights of shoot and root, nitrogen use efficiency), and the N-flux in plant-soil system, taking into account the nitrate leached due to over irrigation events. The activities of enzymes involved in the nitrogen uptake (nitrate reductase, glutamate synthase and glutamine synthase), and the nitrogen form accumulated in the plant tissues (total N, protein and NO3-) were evaluated. The results show that the application to the soil of 150 kg/ha BPs allows to increase lettuce growth and nitrogen use efficiency, trough stimulation of N-metabolism and accumulation of proteins, and hence to reduce the use of MF by 40%, thus decreasing the nitrate leaching. These findings suggest that the use of BPs as biostimulant greatly contributes to reduce the consumption of mineral fertilizers, and to mitigate the environmental impact caused by nutrients leaching, according to European common agricultural policy, that encourages R&D of new bioproducts for sustainable eco-friendly agriculture.


Asunto(s)
Nitrógeno , Suelo , Nitrógeno/metabolismo , Nitratos/análisis , Lactuca/metabolismo , Fertilizantes , Agricultura
18.
New Phytol ; 196(3): 945-954, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22988918

RESUMEN

Symmetry is an important feature of floral structure, and floral symmetries are diverse and often complex. We use a new morphometric approach for analysing shapes with complex types of symmetry, which partitions shape variation into a component of symmetric variation and different components of asymmetry. This approach, based on the mathematical theory of symmetry groups, can be used for landmark configurations with any type of symmetry and is therefore promising as a general framework for morphometric analyses of floral symmetry and asymmetry. We demonstrate this approach by quantifying floral shape variation in a wild population of Erysimum mediohispanicum (Brassicaceae). Flowers of this species are disymmetric, so that the symmetry in the left-right and adaxial-abaxial directions can be considered separately and in combination. Both principal component analysis and Procrustes ANOVA indicate that symmetric variation accounts for most of the total variance and that adaxial-abaxial asymmetry is the dominant component of fluctuating asymmetry. Each component is associated with specific patterns of shape variation. These results illustrate the potential of the new method and suggest new areas for future research. The new morphometric approach is promising for further analyses of floral symmetry and asymmetry in evolutionary and developmental contexts.


Asunto(s)
Biología Computacional/métodos , Erysimum/anatomía & histología , Flores/anatomía & histología , Desarrollo de la Planta , Análisis de Varianza , Evolución Biológica , Erysimum/crecimiento & desarrollo , Flores/crecimiento & desarrollo , Análisis de Componente Principal , Especificidad de la Especie
19.
Oecologia ; 170(4): 1009-20, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22717625

RESUMEN

Understanding how plant-animal interactions shape plant regeneration is traditionally examined at local scales. In contrast, landscape ecologists working at regional scales often have to infer the mechanisms underlying vegetation patterns. In this study, we empirically explored how landscape attributes (patch connectivity, size, shape, irradiance, slope, and elevation) influence biotic interactions in 1- and 2-year seedlings and saplings of Quercus ilex. We combined field data and GIS-based information under a set of five connectivity scenarios, presuming low, intermediate, and long-distance seed dispersal. Our study emphasizes that landscape, apart from its direct effects on plants, plays a key, albeit indirect, role in plant demography through its effects on seed dispersers and predators. Moreover, the effects of landscape on recruitment differed between plant life stages. One-year seedlings and saplings appear to depend more on plant-animal interactions, while 2-year seedlings depend more on irradiance. Differences in patch connectivity resulted in direct and indirect effects on biotic interactions, which, in turn, produced contrasting positive and negative effects on regeneration at different stages of the life cycle. While jays and wild boars seem crucial to all life stages and most of the connectivity scenarios, rodents and herbivores affected only 1-year seedlings and saplings, respectively, and only a few of the connectivity scenarios. By simultaneously including an ensemble of explanatory factors, our study emphasizes that regeneration depends on a set of key drivers, both abiotic (i.e. irradiance) and biotic (i.e. jays and wild boars), whose effects are greatly modulated by landscape traits.


Asunto(s)
Ecosistema , Dispersión de las Plantas , Quercus/crecimiento & desarrollo , Animales , Estadios del Ciclo de Vida , Passeriformes , Plantones/crecimiento & desarrollo , Sus scrofa
20.
Nutrients ; 14(2)2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35057541

RESUMEN

The vitamin D receptor (VDR), a member of the nuclear receptor superfamily of transcriptional regulators, is crucial to calcitriol signalling. VDR is regulated by genetic and environmental factors and it is hypothesised that the response to vitamin D supplementation could be modulated by genetic variants in the VDR gene. The best studied polymorphisms in the VDR gene are Apal (rs7975232), BsmI (rs1544410), Taql (rs731236) and Fokl (rs10735810). We conducted a systematic review and meta-analysis to evaluate the response to vitamin D supplementation according to the BsmI, TaqI, ApaI and FokI polymorphisms. We included studies that analysed the relationship between the response to vitamin D supplementation and the genotypic distribution of these polymorphisms. We included eight studies that enrolled 1038 subjects. The results showed no significant association with the BsmI and ApaI polymorphisms (p = 0.081 and p = 0.63) and that the variant allele (Tt+tt) of the TaqI polymorphism and the FF genotype of the FokI variant were associated with a better response to vitamin D supplementation (p = 0.02 and p < 0.001). In conclusion, the TaqI and FokI polymorphisms could play a role in the modulation of the response to vitamin D supplementation, as they are associated with a better response to supplementation.


Asunto(s)
Suplementos Dietéticos , Polimorfismo Genético , Receptores de Calcitriol/genética , Vitamina D/administración & dosificación , Adolescente , Adulto , Anciano , Alelos , Niño , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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