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1.
Sci Total Environ ; 810: 152232, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896132

RESUMO

Local communities, informed about the main post-fire environmental threats, applied land restoration techniques after the 2017 Ponte Caldelas wildfire (Galicia, Spain). Volunteers crews, supervised by local researchers/technicians identified high-severity burned areas and applied: post-fire mulch by using corn mulch (chopped corn at a rate of 4 Mg ha-1), corn strip mulch (chopped corn on 1-m wide contourline-strips at the bottom of plots, at 1 Mg ha-1) and wheat mulch (wheat straw, at 2 Mg ha-1), as well as acorn seeding with native oak (Quercus robur) acorns. Furthermore, the mulch effect on seed germination/root elongation was tested in the laboratory using direct topsoil samples and <0.45 microns-filtered soil solutions. Soil erosion during the first post-fire year was 27-11 Mg ha-1 for the Parada-Laforet sites, respectively. Corn, corn strip, and wheat mulching were very effective at reducing soil erosion, leading to 95, 76% and 93% less erosion than in untreated plots. During post-fire year 2 mulching was still effective at reducing soil erosion in the case of corn (87%) and corn strip mulch (73%), but less effective with straw mulch (36%). For the third year no differences were observed. Acorn seedling establishment failed in 96% of the cases. Still, survival rate of the germinated acorns was significantly higher on the mulched (50%) than on the untreated spots (26%; p<0.05). The laboratory experiments also showed higher germination rates, shoot length and biomass in mulched than untreated soils. The results demonstrated that the mulching measures applied by the local volunteers were effective for preventing soil erosion after forest fires. The success of ecosystem restoration with acorn seeding was low due to the low germination and the high predation by rodents, and further research is needed to scale acorn seeding to natural recruitment rates.


Assuntos
Incêndios , Quercus , Incêndios Florestais , Ecossistema , Solo
2.
Plant Biol (Stuttg) ; 18(6): 973-980, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27500664

RESUMO

Context-dependency in species interactions is widespread and can produce concomitant patterns of context-dependent selection. Masting (synchronous production of large seed crops at irregular intervals by a plant population) has been shown to reduce seed predation through satiation (reduction in rates of seed predation with increasing seed cone output) and thus represents an important source of context-dependency in plant-animal interactions. However, the evolutionary consequences of such dynamics are not well understood. Here we describe masting behaviour in a Mediterranean model pine species (Pinus pinaster) and present a test of the effects of masting on selection by seed predators on reproductive output. We predicted that masting, by enhancing seed predator satiation, could in turn strengthen positive selection by seed predators for larger cone output. For this we collected six-year data (spanning one mast year and five non-mast years) on seed cone production and seed cone predation rates in a forest genetic trial composed by 116 P. pinaster genotypes. Following our prediction, we found stronger seed predator satiation during the masting year, which in turn led to stronger seed predator selection for increased cone production relative to non-masting years. These findings provide evidence that masting can alter the evolutionary outcome of plant-seed predator interactions. More broadly, our findings highlight that changes in consumer responses to resource abundance represent a widespread mechanism for predicting and understanding context dependency in plant-consumer evolutionary dynamics.


Assuntos
Pinus/fisiologia , Sementes/fisiologia , Animais , Evolução Biológica , Biomassa , Comportamento Alimentar , Florestas , Genótipo , Pinus/crescimento & desenvolvimento , Comportamento Predatório , Reprodução , Saciação , Sementes/crescimento & desenvolvimento
3.
Heredity (Edinb) ; 114(1): 116-24, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25160045

RESUMO

Quantitative seed provisioning is an important life-history trait with strong effects on offspring phenotype and fitness. As for any other trait, heritability estimates are vital for understanding its evolutionary dynamics. However, being a trait in between two generations, estimating additive genetic variation of seed provisioning requires complex quantitative genetic approaches for distinguishing between true genetic and environmental maternal effects. Here, using Maritime pine as a long-lived plant model, we quantified additive genetic variation of cone and seed weight (SW) mean and SW within-individual variation. We used a powerful approach combining both half-sib analysis and parent-offspring regression using several common garden tests established in contrasting environments to separate G, E and G × E effects. Both cone weight and SW mean showed significant genetic variation but were also influenced by the maternal environment. Most of the large variation in SW mean was attributable to additive genetic effects (h(2)=0.55-0.74). SW showed no apparent G × E interaction, particularly when accounting for cone weight covariation, suggesting that the maternal genotypes actively control the SW mean irrespective of the amount of resources allocated to cones. Within-individual variation in SW was low (12%) relative to between-individual variation (88%), and showed no genetic variation but was largely affected by the maternal environment, with greater variation in the less favourable sites for pine growth. In summary, results were very consistent between the parental and the offspring common garden tests, and clearly indicated heritable genetic variation for SW mean but not for within-individual variation in SW.


Assuntos
Interação Gene-Ambiente , Variação Genética , Pinus/genética , Característica Quantitativa Herdável , Sementes/anatomia & histologia , Meio Ambiente , Genótipo , Funções Verossimilhança , Modelos Genéticos , Sementes/genética , Espanha
4.
Heredity (Edinb) ; 111(3): 248-55, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23652562

RESUMO

Although maternal environmental effects are increasingly recognized as an important source of phenotypic variation with relevant impacts in evolutionary processes, their relevance in long-lived plants such as pine trees is largely unknown. Here, we used a powerful sample size and a strong quantitative genetic approach to analyse the sources of variation of early seedling performance and to identify seed mass (SM)-dependent and -independent maternal environmental effects in Maritime pine. We measured SM of 8924 individual seeds collected from 10 genotypes clonally replicated in two environments of contrasting quality (favourable and stressful), and we measured seedling growth rate and biomass allocation to roots and shoots. SM was extremely variable (up to 14-fold) and strongly determined by the maternal environment and the genotype of the mother tree. The favourable maternal environment led to larger cones, larger seeds and reduced SM variability. The maternal environment also determined the offspring phenotype, with seedlings coming from the favourable environment being 35% larger and with greater root/shoot ratio. Transgenerational plasticity appears, thus, to be a relevant source of phenotypic variation in the early performance of this pine species. Seed provisioning explained most of the effect of the maternal environment on seedling total biomass. Environmental maternal effects on seedling biomass allocation were, however, determined through SM-independent mechanisms, suggesting that other epigenetic regulation channels may be involved.


Assuntos
Impressão Genômica , Pinus/genética , Sementes/genética , Meio Ambiente , Fenótipo , Pinus/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Árvores/genética , Árvores/crescimento & desenvolvimento
5.
Heredity (Edinb) ; 110(5): 449-56, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23232833

RESUMO

The apparent failure of invasions by alien pines in Europe has been explained by the co-occurrence of native pine congeners supporting herbivores that might easily recognize the new plants as hosts. Previous studies have reported that exotic pines show reduced tolerance and capacity to induce resistance to those native herbivores. We hypothesize that limited genetic variation in resistance to native herbivores and the existence of evolutionary trade-offs between growth and resistance could represent additional potential constraints on the evolution of invasiveness of exotic pines outside their natural range. In this paper, we examined genetic variation for constitutive and induced chemical defences (measured as non-volatile resin in the stem and total phenolics in the needles) and resistance to two major native generalist herbivores of pines in cafeteria bioassays (the phloem-feeder Hylobius abietis and the defoliator Thaumetopoea pityocampa) using half-sib families drawn from a sample of the population of Pinus radiata introduced to Spain in the mid-19th century. We found (i) significant genetic variation, with moderate-to-high narrow-sense heritabilities for both the production of constitutive non-volatile resin and induced total phenolics, and for constitutive resistance against T. pityocampa in bioassays, (ii) no evolutionary trade-offs between plant resistance and growth traits or between the production of different quantitative chemical defences and (iii) a positive genetic correlation between constitutive resistance to the two studied herbivores. Overall, results of our study indicate that the exotic pine P. radiata has limited genetic constraints on the evolution of resistance against herbivores in its introduced range, suggesting that, at least in terms of interactions with these enemies, this pine species has potential to become invasive in the future.


Assuntos
Evolução Biológica , Variação Genética , Herbivoria , Pinus/genética , Acetatos/análise , Animais , Besouros , Ciclopentanos/análise , Europa (Continente) , Comportamento Alimentar , Espécies Introduzidas , Mariposas , Oxilipinas/análise , Fenótipo , Floema/química , Floema/genética , Pinus/química , Pinus/crescimento & desenvolvimento , Pinus/fisiologia , Polifenóis/análise , Característica Quantitativa Herdável , Resinas Vegetais/análise , Resinas Vegetais/química , Espanha
6.
Plant Biol (Stuttg) ; 14 Suppl 1: 66-72, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21972958

RESUMO

We studied the effects of phosphorus fertilisation on foliar terpene concentrations and foliar volatile terpene emission rates in six half-sib families of Pinus pinaster Ait. seedlings. Half of the seedlings were resistant to attack of the pine weevil Hylobius abietis L., a generalist phloem feeder, and the remaining seedlings were susceptible to this insect. We hypothesised that P stress could modify the terpene concentration in the needles and thus lead to altered terpene emission patterns relevant to plant-insect signalling. The total concentration and emission rate ranged between 5732 and 13,995 µg·g(-1) DW and between 2 and 22 µg·g(-1) DW·h(-1), respectively. Storage and emission were dominated by the isomers α- and ß-pinene (77.2% and 84.2% of the total terpene amount amassed and released, respectively). In both resistant and susceptible families, P stress caused an increase of 31% in foliar terpene concentration with an associated 5-fold decrease in terpene emission rates. A higher terpene content in the leaves implies that the 'excess carbon', available under limiting growth conditions (P scarcity), is allocated to terpene production. Sensitive families showed a greater increase in terpene emission rates with increasing P concentrations, which could explain their susceptibility to H. abietis.


Assuntos
Fósforo/metabolismo , Pinus/genética , Pinus/metabolismo , Folhas de Planta/química , Terpenos/análise , Gorgulhos , Animais , Fertilizantes , Fotossíntese , Transpiração Vegetal , Compostos Orgânicos Voláteis/metabolismo
7.
Methods Find Exp Clin Pharmacol ; 24(9): 573-8, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12616703

RESUMO

Animal studies suggest that fish oils are capable of modulating the cell functions of immune system and there is some evidence that the effects of fish oils on immune function are due to fatty acids rather than trace elements or antioxidants. The major objectives of this study were: i) to identify a fish species with high nutritional value able to improve pig feeding conditions; ii) to utilize diets that modulate the immune system early in life in pigs and; iii) to enhance growth rate on a physiological basis. With the aim of maximizing feeding intake after weaning in order to reduce stress and increase growth rate, a study was carried out on 300 pigs supplemented with different fish extracts obtained by advanced biotechnological methods. The results of this work suggest that the lipoproteins obtained from the Trachurus trachurus (E-JUR-94013) species may have a great effect as both an immunomodulating compound (acting mainly on the regulation of IgA synthesis and/or release) and as a hypocholesterolemic compound, reducing the total cholesterol level in the serum of treated pigs. Both effects resulted in better pig growth, demonstrating that E-JUR-94013 can also be used as a natural growth promoter and an immune enhancer.


Assuntos
Adjuvantes Imunológicos/farmacologia , Suplementos Nutricionais , Peixes , Lipoproteínas/farmacologia , Animais , Imunoglobulina A/biossíntese , Imunoglobulina G/biossíntese , Suínos
8.
Methods Find Exp Clin Pharmacol ; 22(7): 585-94, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11196347

RESUMO

The aim of this study was to evaluate the effects of two doses of anapsos in comparison with placebo on cognitive performance, brain bioelectrical activity pattern and cerebral hemodynamic parameters in patients with mild to moderate senile dementia of vascular type and Alzheimer type. Forty-five patients (age 73.8 +/- 7.6 years; range 56-89 years) with mild to moderate senile dementia (Global Deterioration Scale: stages 3-5) of the vascular (VD; n = 22) or the Alzheimer type (AD; n = 23) were included in a double-blind randomized placebo-controlled clinical trial. After a 2-week period of drug washout, patients were treated with placebo (n = 15; age 72.7 +/- 7.5 years), 360 mg/day of anapsos (n = 15; age 75.5 +/- 7.2 years), or 720 mg/day of anapsos (n = 15; age 73 +/- 7.7 years) for 4 weeks (28 days). At baseline and after the 4-week period of double-blind treatment, cognitive performance, brain bioelectrical activity power and blood flow hemodynamics in the middle cerebral arteries were evaluated with ADAScog, brain mapping and transcranial Doppler ultrasonography, respectively. Patients receiving 360 mg/day of anapsos showed a significant improvement in cognitive performance after treatment (ADAScog scores: p < 0.05) that was not observed in patients treated with placebo or 720 mg/day of anapsos. As compared to placebo, anapsos (360 mg/day) induced a significant improvement in ADAScog scores in mild senile dementia patients (p < 0.01) and in the subset of patients with AD (p < 0.05). Anapsos (360 mg/day) also increased cerebral blood flow velocities in left and right middle cerebral arteries in the subgroup of AD patients, whereas with the dose of 720 mg/kg this increase was only observed in the left side. Patients treated with anapsos (360 mg/day) showed a decrease in relative delta power and an increase in relative theta and alpha brain bioelectrical activity frequencies, indicating an acceleration of the EEG pattern. The present results show that anapsos (360 mg/day) improves cognitive performance, cerebral blood perfusion and brain bioelectrical activity in patients with senile dementia. These effects of anapsos were more marked in demented patients with mild mental deterioration and/or with dementia of the Alzheimer type.


Assuntos
Adjuvantes Imunológicos/farmacologia , Doença de Alzheimer/fisiopatologia , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Eletroencefalografia/efeitos dos fármacos , Glicosídeos/farmacologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Cognição/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/fisiologia , Projetos Piloto , Estatísticas não Paramétricas
9.
Methods Find Exp Clin Pharmacol ; 21(9): 633-44, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10669911

RESUMO

Cytidine 5'-diphosphocholine (citicoline) is a an endogenous intermediate in the biosynthesis of structural membrane phospholipids and brain acetylcholine. Citicoline has been extensively used for the treatment of neurodegenerative disorders associated with head trauma, stroke, brain aging, cerebrovascular pathology and Alzheimer's disease. In this study we have investigated the efficacy and safety of the treatment with citicoline versus placebo in patients with Alzheimer disease. Thirty patients (age = 73.0 +/- 8.5 years; range = 57-87 years) with mild to moderate senile dementia (GDS: stages 3-6) of the Alzheimer type were included in a double-blind, randomized and placebo-controlled clinical trial. After a 2-week period of drug washout, patients were treated with i) placebo (n = 17; age = 73 +/- 5 years) or ii) 1,000 mg/day of citicoline (n = 13; age = 76 +/- 9 years) for 12 weeks (84 days). Examinations were done at baseline (T0) and after the 12 weeks of treatment (T12). As compared to placebo, citicoline improved cognitive performance in Alzheimer's disease patients with APOE E4 (ADAS: difference between groups = -3.2 +/- 1.8 scores, p < 0.05; ADAS-cog: difference between groups = -2.3 +/- 1.5, ns); and this improvement on cognition was more pronounced (ADAS, p < 0.01; ADAS-cog: difference between groups = -2.8 +/- 1.3, p < 0.06) in patients with mild dementia (GDS < 5). Citicoline also increased cerebral blood flow velocities in comparison with placebo (p < 0.05) when transcranial Doppler recordings from both hemispheres were considered together, as well as diastolic velocity in the left middle cerebral artery (p < 0.05). Patients treated with citicoline showed an increase in the percentage of brain bioelectrical activity of alpha (occipital electrodes) and theta type (left side electrodes), accompanied by a decrease in relative delta activity particularly marked in the left temporal lobe. Significant differences with respect to placebo (p < 0.05) were observed for theta activity in several fronto-parieto-temporal electrodes of the left hemisphere. Treatment with citicoline tended to reduce serum IL-1 beta levels, mainly after 4 weeks of administration, with no modified blood histamine content. In addition, neither adverse side effects nor alterations in biological and hematological parameters were induced by citicoline. The present data indicate that citicoline (1,000 mg/day) is well tolerated and improves cognitive performance, cerebral blood perfusion and the brain bioelectrical activity pattern in AD patients. According to our results, it seems that citicoline might be a useful treatment in Alzheimer's disease, and that the efficacy of this compound is greater in patients with mild mental deterioration and/or bearing the epsilon 4 allele of the APOE.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Apolipoproteínas E/genética , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Citidina Difosfato Colina/uso terapêutico , Idoso , Doença de Alzheimer/genética , Método Duplo-Cego , Eletroencefalografia , Feminino , Genótipo , Hemodinâmica/efeitos dos fármacos , Histamina/sangue , Humanos , Interleucina-1/sangue , Masculino , Pessoa de Meia-Idade , Nootrópicos/farmacologia , Projetos Piloto , Placebos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fatores de Tempo
12.
Methods Find Exp Clin Pharmacol ; 19(5): 299-309, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9379778

RESUMO

Rats with neurotoxic lesions, induced by single or double bilateral injections of ibotenic acid into different parts of the nucleus basalis of Meynert (nbM), showed increased psychomotor activity (PMA) and impaired learning in a passive avoidance task. Behavioral deficits were similar in all the groups of lesioned animals, suggesting that the lesion site was not relevant for the ibotenic effects under testing procedures used here. In another experiment, nbM-lesioned rats received acute or daily (5 days) i.p. injections of vehicle or anapsos (100 mg/kg) from the 7th day after surgery. Data indicated that nbM lesions induced an increased production of interleukin-1 beta (IL-1 beta), motor hyperactivity and learning impairment, and that anapsos, a vegetal extract with immunomodulatory activity, reversed brain IL-1 beta overexpression and behavioral alterations in lesioned rats. These results confirm the involvement of IL-1 beta in neurodegeneration associated with cholinergic deficits and the potential utility of compounds with neuroimmunotrophic activity as a new therapeutic strategy in neurodegenerative disorders.


Assuntos
Adjuvantes Imunológicos/farmacologia , Glicosídeos/farmacologia , Interleucina-1/biossíntese , Substância Inominada/efeitos dos fármacos , Adjuvantes Imunológicos/administração & dosagem , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Agonistas de Aminoácidos Excitatórios/administração & dosagem , Feminino , Glicosídeos/administração & dosagem , Ácido Ibotênico/administração & dosagem , Injeções Intraperitoneais , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Substância Inominada/patologia
13.
Methods Find Exp Clin Pharmacol ; 18(3): 197-203, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8738071

RESUMO

S-9977-2 is a new molecule with promnesic and antiamnesic properties. In this study, we investigated the effects of i.p. administration of S-9977-2 on histamine (HA) levels in several regions of the rat brain, and also in peripheral areas, using high performance liquid chromatography (HPLC) with fluorometric detection. S-9977-2 (0.025 mg/kg) induced an increase in the content of HA in the anterior hypothalamic region, with a significant effect 30 min after injection (1.77 +/- 0.36 nmol/g vs. 2.43 +/- 0.40 nmol/g; p < 0.01). It did not significantly modify HA levels in the posterior hypothalamic region, hippocampus, fronto-parietal cortex, blood, spleen, or adrenal glands. A clear tendency to increase HA content was observed in the hippocampus (0.16 +/- 0.03 nmol/g vs. 0.39 +/- 0.31 nmol/g, ns) and fronto-parietal cortex (0.55 +/- 0.45 nmol/g vs. 0.70 +/- 0.28 nmol/g; ns). S-9977-2 at doses of 0.005 and 0.125 mg/kg i.p. did not produce any significant change in HA levels in any of the samples tested 30 min after administration. The present results demonstrate that S-9977-2 increases HA levels in the anterior hypothalamus, which is the brain region with the highest content in histaminergic fibers. This fact suggests that the neuronal HA system might be involved directly or indirectly in the pharmacological actions of S-9977-2.


Assuntos
Inibidores da Colinesterase/farmacologia , Histamina/metabolismo , Piperazinas/farmacologia , Xantinas/farmacologia , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão , Feminino , Histamina/sangue , Ratos , Ratos Sprague-Dawley , Baço/efeitos dos fármacos , Baço/metabolismo
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