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1.
Plant Biol (Stuttg) ; 25(6): 880-891, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37655516

RESUMO

Epiphytes offer an appealing framework to disentangle the contributions of chance, biotic and abiotic drivers of species distributions. In the context of the stress-gradient theory, we test the hypotheses that (i) deterministic (i.e., non-random) factors play an increasing role in communities from young to old trees, (ii) negative biotic interactions increase on older trees and towards the tree base, and (iii) positive interactions show the reverse pattern. Bryophyte species distributions and abiotic conditions were recorded on a 1.1 ha tropical rainforest canopy crane site. We analysed co-occurrence patterns in a niche modelling framework to disentangle the roles of chance, abiotic factors and putative biotic interactions among species pairs. 76% of species pairs resulted from chance. Abiotic factors explained 78% of non-randomly associated species pairs, and co-occurrences prevailed over non-coincidences in the remaining species pairs. Positive and negative interactions mostly involved species pairs from the same versus different communities (mosses versus liverworts) and life forms, respectively. There was an increase in randomly associated pairs from large to small trees. No increase in negative interactions from young to old trees or from the canopy to the base was observed. Our results suggest that epiphytic bryophyte community composition is primarily driven by environmental filtering, whose importance increases with niche complexity and diversity. Biotic interactions play a secondary role, with a very marginal contribution of competitive exclusion. Biotic interactions vary among communities (mosses versus liverworts) and life forms, facilitation prevailing among species from the same community and life form, and competition among species from different communities and life forms.


Assuntos
Briófitas , Floresta Úmida , China , Árvores
3.
Med Intensiva (Engl Ed) ; 45(5): 298-312, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34059220

RESUMO

Non-invasive respiratory support (NIRS) in adult, pediatric, and neonatal patients with acute respiratory failure (ARF) comprises two treatment modalities, non-invasive mechanical ventilation (NIMV) and high-flow nasal cannula (HFNC) therapy. However, experts from different specialties disagree on the benefit of these techniques in different clinical settings. The objective of this consensus was to develop a series of good clinical practice recommendations for the application of non-invasive support in patients with ARF, endorsed by all scientific societies involved in the management of adult and pediatric/neonatal patients with ARF. To this end, the different societies involved were contacted, and they in turn appointed a group of 26 professionals with sufficient experience in the use of these techniques. Three face-to-face meetings were held to agree on recommendations (up to a total of 71) based on a literature review and the latest evidence associated with 3 categories: indications, monitoring and follow-up of NIRS. Finally, the experts from each scientific society involved voted telematically on each of the recommendations. To classify the degree of agreement, an analogue classification system was chosen that was easy and intuitive to use and that clearly stated whether the each NIRS intervention should be applied, could be applied, or should not be applied.


Assuntos
Ventilação não Invasiva , Insuficiência Respiratória , Adulto , Cânula , Criança , Consenso , Humanos , Recém-Nascido , Oxigênio , Piruvatos , Insuficiência Respiratória/terapia , Sociedades Científicas
4.
Med Intensiva (Engl Ed) ; 45(5): 298-312, 2021.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33309463

RESUMO

Non-invasive respiratory support (NIRS) in adult, pediatric, and neonatal patients with acute respiratory failure (ARF) comprises two treatment modalities, non-invasive mechanical ventilation (NIMV) and high-flow nasal cannula (HFNC) therapy. However, experts from different specialties disagree on the benefit of these techniques in different clinical settings. The objective of this consensus was to develop a series of good clinical practice recommendations for the application of non-invasive support in patients with ARF, endorsed by all scientific societies involved in the management of adult and pediatric/neonatal patients with ARF. To this end, the different societies involved were contacted, and they in turn appointed a group of 26 professionals with sufficient experience in the use of these techniques. Three face-to-face meetings were held to agree on recommendations (up to a total of 71) based on a literature review and the latest evidence associated with 3 categories: indications, monitoring and follow-up of NIRS. Finally, the experts from each scientific society involved voted telematically on each of the recommendations. To classify the degree of agreement, an analogue classification system was chosen that was easy and intuitive to use and that clearly stated whether the each NIRS intervention should be applied, could be applied, or should not be applied.

5.
Nat Commun ; 11(1): 5601, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154374

RESUMO

The extent to which species can balance out the loss of suitable habitats due to climate warming by shifting their ranges is an area of controversy. Here, we assess whether highly efficient wind-dispersed organisms like bryophytes can keep-up with projected shifts in their areas of suitable climate. Using a hybrid statistical-mechanistic approach accounting for spatial and temporal variations in both climatic and wind conditions, we simulate future migrations across Europe for 40 bryophyte species until 2050. The median ratios between predicted range loss vs expansion by 2050 across species and climate change scenarios range from 1.6 to 3.3 when only shifts in climatic suitability were considered, but increase to 34.7-96.8 when species dispersal abilities are added to our models. This highlights the importance of accounting for dispersal restrictions when projecting future distribution ranges and suggests that even highly dispersive organisms like bryophytes are not equipped to fully track the rates of ongoing climate change in the course of the next decades.


Assuntos
Briófitas/fisiologia , Mudança Climática , Dispersão Vegetal/fisiologia , Briófitas/classificação , Briófitas/crescimento & desenvolvimento , Ecossistema , Europa (Continente) , Extinção Biológica , Previsões , Modelos Teóricos , Vento
6.
J Perinatol ; 40(2): 226-231, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767979

RESUMO

OBJECTIVE: Determine the suitability of transcutaneous bilirubin (TCB) as a tool to assess the effectiveness of phototherapy on patched skin. STUDY DESIGN: A prospective observational study was conducted. We covered a fragment of skin (sternum) with a photo-opaque patch. Several simultaneous TCB and TSB measurements were performed with the JM-105 bilirubinometer. Bland and Altman test evaluated the agreement between bilirubin levels. RESULT: A total of 217 patients were studied, 48.8% were preterm. The mean difference between TSB and TCB before the start of treatment was 1.07 mg/dL. During phototherapy, differences on covered skin were 0.52, 0.27, and 0.39 mg/dL at 24, 48, and 72 h of therapy respectively. The best correlation was observed at 48 h in preterm infants. CONCLUSION: The measurement of TCB on patched skin (PTCB) is useful for monitoring the response to phototherapy in term and preterm infants. We use a patch with a removable flap that eases successive measures without disturbing the patients.


Assuntos
Bilirrubina/análise , Bilirrubina/sangue , Icterícia Neonatal/terapia , Monitorização Fisiológica/instrumentação , Fototerapia , Pele , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro/sangue , Icterícia Neonatal/sangue , Masculino , Monitorização Fisiológica/métodos , Triagem Neonatal , Estudos Prospectivos
7.
Am J Perinatol ; 35(2): 170-176, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28854447

RESUMO

INTRODUCTION: Antenatal magnesium sulfate (MgSO4) administration has shown to be effective in minimizing cerebral palsy and severe motor dysfunction at the age of 2 years. The aim of this study is to determine the relationship between the magnesium dose delivered to the mother and the magnesium concentration in the neonates. MATERIALS AND METHODS: A prospective cohort study was conducted on neonates of less than 32 weeks' gestation admitted to the neonatal intensive care unit of University Hospital Complex of Vigo from December 2012 to July 2015. Comparative analysis of magnesium levels between the groups of neonates exposed to MgSO4 and the control group. RESULTS: A total of 118 neonates were included in the study. The mothers of 62 of them had received MgSO4 as a neuroprotective agent. There was a significant correlation between the full dose of MgSO4 received by the mother and the levels of magnesium in the neonate in the first 24 hours of life (r2 = 0.397; p < 0.001). CONCLUSION: The MgSO4 dose received by the mother has a linear relationship with the magnesium levels obtained in neonates.


Assuntos
Recém-Nascido Prematuro/sangue , Sulfato de Magnésio/uso terapêutico , Magnésio/sangue , Fármacos Neuroprotetores/uso terapêutico , Estudos de Casos e Controles , Paralisia Cerebral/prevenção & controle , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Modelos Lineares , Masculino , Transtornos Motores/prevenção & controle , Gravidez , Cuidado Pré-Natal/métodos , Estudos Prospectivos
8.
An Pediatr (Barc) ; 83(5): 354.e1-6, 2015 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-25840706

RESUMO

The recommendations included in this document will be part a series of updated reviews of the literature on respiratory support in the newborn infant. These recommendations are structured into twelve modules, and in this work module 7 is presented. Each module is the result of a consensus process including all members of the Surfactant and Respiratory Group of the Spanish Society of Neonatology. They represent a summary of the published papers on each specific topic, and of the clinical experience of each one of the members of the group.


Assuntos
Neonatologia , Óxido Nítrico/administração & dosagem , Respiração Artificial/métodos , Tensoativos/administração & dosagem , Consenso , Humanos , Recém-Nascido
9.
Mol Ecol ; 23(17): 4274-90, 2014 09.
Artigo em Inglês | MEDLINE | ID: mdl-25041483

RESUMO

Studying patterns of species distributions along elevation gradients is frequently used to identify the primary factors that determine the distribution, diversity and assembly of species. However, despite their crucial role in ecosystem functioning, our understanding of the distribution of below-ground fungi is still limited, calling for more comprehensive studies of fungal biogeography along environmental gradients at various scales (from regional to global). Here, we investigated the richness of taxa of soil fungi and their phylogenetic diversity across a wide range of grassland types along a 2800 m elevation gradient at a large number of sites (213), stratified across a region of the Western Swiss Alps (700 km(2)). We used 454 pyrosequencing to obtain fungal sequences that were clustered into operational taxonomic units (OTUs). The OTU diversity-area relationship revealed uneven distribution of fungal taxa across the study area (i.e. not all taxa are everywhere) and fine-scale spatial clustering. Fungal richness and phylogenetic diversity were found to be higher in lower temperatures and higher moisture conditions. Climatic and soil characteristics as well as plant community composition were related to OTU alpha, beta and phylogenetic diversity, with distinct fungal lineages suggesting distinct ecological tolerances. Soil fungi, thus, show lineage-specific biogeographic patterns, even at a regional scale, and follow environmental determinism, mediated by interactions with plants.


Assuntos
Biodiversidade , Fungos/classificação , Poaceae/microbiologia , Microbiologia do Solo , DNA Fúngico/genética , Fungos/genética , Filogenia , Análise de Sequência de DNA , Análise Espacial , Suíça
10.
J Environ Manage ; 131: 185-95, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24161807

RESUMO

Species distribution models (SDMs) studies suggest that, without control measures, the distribution of many alien invasive plant species (AIS) will increase under climate and land-use changes. Due to limited resources and large areas colonised by invaders, management and monitoring resources must be prioritised. Choices depend on the conservation value of the invaded areas and can be guided by SDM predictions. Here, we use a hierarchical SDM framework, complemented by connectivity analysis of AIS distributions, to evaluate current and future conflicts between AIS and high conservation value areas. We illustrate the framework with three Australian wattle (Acacia) species and patterns of conservation value in Northern Portugal. Results show that protected areas will likely suffer higher pressure from all three Acacia species under future climatic conditions. Due to this higher predicted conflict in protected areas, management might be prioritised for Acacia dealbata and Acacia melanoxylon. Connectivity of AIS suitable areas inside protected areas is currently lower than across the full study area, but this would change under future environmental conditions. Coupled SDM and connectivity analysis can support resource prioritisation for anticipation and monitoring of AIS impacts. However, further tests of this framework over a wide range of regions and organisms are still required before wide application.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais/métodos , Modelos Teóricos , Plantas
11.
Ecol Evol ; 2(6): 1260-77, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22833799

RESUMO

The major intention of the present study was to investigate whether an approach combining the use of niche-based palaeodistribution modeling and phylo-geography would support or modify hypotheses about the Quaternary distributional history derived from phylogeographic methods alone. Our study system comprised two closely related species of Alpine Primula. We used species distribution models based on the extant distribution of the species and last glacial maximum (LGM) climate models to predict the distribution of the two species during the LGM. Phylogeographic data were generated using amplified fragment length polymorphisms (AFLPs). In Primula hirsuta, models of past distribution and phylogeographic data are partly congruent and support the hypothesis of widespread nunatak survival in the Central Alps. Species distribution models (SDMs) allowed us to differentiate between alpine regions that harbor potential nunatak areas and regions that have been colonized from other areas. SDMs revealed that diversity is a good indicator for nunataks, while rarity is a good indicator for peripheral relict populations that were not source for the recolonization of the inner Alps. In P. daonensis, palaeo-distribution models and phylogeographic data are incongruent. Besides the uncertainty inherent to this type of modeling approach (e.g., relatively coarse 1-km grain size), disagreement of models and data may partly be caused by shifts of ecological niche in both species. Nevertheless, we demonstrate that the combination of palaeo-distribution modeling with phylogeographical approaches provides a more differentiated picture of the distributional history of species and partly supports (P. hirsuta) and partly modifies (P. daonensis and P. hirsuta) hypotheses of Quaternary distributional history. Some of the refugial area indicated by palaeodistribution models could not have been identified with phylogeographic data.

12.
J Evol Biol ; 25(8): 1658-66, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22725645

RESUMO

The amount of nitrogen required to complete an insect's life cycle may vary greatly among species that have evolved distinct life history traits. Myrmecophilous caterpillars in the Lycaenidae family produce nitrogen-rich exudates from their dorsal glands to attract ants for protection, and this phenomenon has been postulated to shape the caterpillar's host-plant choice. Accordingly, it was postulated that evolution towards myrmecophily in Lycaenidae is correlated with the utilization of nitrogen-rich host plants. Although our results were consistent with the evolutionary shifts towards high-nutrient host plants serving as exaptation for the evolution of myrmecophily in lycaenids, the selection of nitrogen-rich host plants was not confined to lycaenids. Butterfly species in the nonmyrmecophilous family Pieridae also preferred nitrogen-rich host plants. Thus, we conclude that nitrogen is an overall important component in the caterpillar diet, independent of the level of myrmecophily, as nitrogen can enhance the overall insect fitness and survival. However, when nitrogen can be obtained through alternative means, as in socially parasitic lycaenid species feeding on ant brood, the selective pressure for maintaining the use of nutrient-rich host plants is relaxed, enabling the colonization of nitrogen-poor host plants.


Assuntos
Formigas/fisiologia , Evolução Biológica , Borboletas/fisiologia , Nitrogênio/metabolismo , Plantas/química , Simbiose/fisiologia , Animais , Borboletas/classificação , Ecossistema , Filogenia
13.
Mol Ecol ; 18(13): 2819-31, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19500248

RESUMO

The giant hogweed (Heracleum mantegazzianum) has successfully invaded 19 European countries as well as parts of North America. It has become a problematic species due to its ability to displace native flora and to cause public health hazards. Applying population genetics to species invasion can help reconstruct invasion history and may promote more efficient management practice. We thus analysed levels of genetic variation and population genetic structure of H. mantegazzianum in an invaded area of the western Swiss Alps as well as in its native range (the Caucasus), using eight nuclear microsatellite loci together with plastid DNA markers and sequences. On both nuclear and plastid genomes, native populations exhibited significantly higher levels of genetic diversity compared to invasive populations, confirming an important founder event during the invasion process. Invasive populations were also significantly more differentiated than native populations. Bayesian clustering analysis identified five clusters in the native range that corresponded to geographically and ecologically separated groups. In the invaded range, 10 clusters occurred. Unlike native populations, invasive clusters were characterized by a mosaic pattern in the landscape, possibly caused by anthropogenic dispersal of the species via roads and direct collection for ornamental purposes. Lastly, our analyses revealed four main divergent groups in the western Swiss Alps, likely as a consequence of multiple independent establishments of H. mantegazzianum.


Assuntos
Variação Genética , Genética Populacional , Heracleum/genética , Algoritmos , Teorema de Bayes , Análise por Conglomerados , DNA de Cloroplastos/genética , DNA de Plantas/genética , Ecossistema , Geografia , Repetições de Microssatélites , Análise de Sequência de DNA , Suíça
14.
Mol Ecol Resour ; 8(1): 161-3, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21585745

RESUMO

This study reports the isolation and polymorphism characterization of four plastid indels and six nuclear microsatellite loci in the invasive plant Heracleum mantegazzianum. These markers were tested in 27 individuals from two distant H. mantegazzianum populations. Plastid indels revealed the presence of five chlorotypes while five nuclear microsatellite loci rendered polymorphism. Applications of these markers include population genetics and phylogeography of H. mantegazzianum. A very good transferability of markers to Heracleum sphondylium was demonstrated.

16.
Ecol Lett ; 10(8): 701-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17594425

RESUMO

Niche-based models calibrated in the native range by relating species observations to climatic variables are commonly used to predict the potential spatial extent of species' invasion. This climate matching approach relies on the assumption that invasive species conserve their climatic niche in the invaded ranges. We test this assumption by analysing the climatic niche spaces of Spotted Knapweed in western North America and Europe. We show with robust cross-continental data that a shift of the observed climatic niche occurred between native and non-native ranges, providing the first empirical evidence that an invasive species can occupy climatically distinct niche spaces following its introduction into a new area. The models fail to predict the current invaded distribution, but correctly predict areas of introduction. Climate matching is thus a useful approach to identify areas at risk of introduction and establishment of newly or not-yet-introduced neophytes, but may not predict the full extent of invasions.


Assuntos
Centaurea/fisiologia , Clima , Demografia , Ecossistema , Modelos Teóricos , Área Sob a Curva , Europa (Continente) , América do Norte , Dinâmica Populacional , Especificidade da Espécie
19.
An Pediatr (Barc) ; 58(1): 71-3, 2003 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-12628124

RESUMO

Coronary artery anomalies constitute 2.2 % of congenital malformations of the heart. The most common abnormality is anomalous origin of the left coronary artery from the pulmonary trunk, also known as Bland-White-Garland syndrome. Clinical manifestations are due to myocardial ischemia caused by the creation of an arteriovenous shunt. The childhood type of this anomaly presents high mortality from heart failure. The adult type develops myocardial infarction, arrhythmias, sudden cardiac death or signs of congestive heart failure. Surgical repair is essential. Various surgical approaches are available and the treatment of choice is direct left coronary artery reimplantation in the aorta. An alternative technique is to create an aortopulmonary tunnel (Takeuchi technique). Marked improvement is usually observed after surgical repair. We report two cases of myocardial ischemia due to coronary anomalies.


Assuntos
Doença das Coronárias/etiologia , Anomalias dos Vasos Coronários/complicações , Adolescente , Criança , Feminino , Humanos , Masculino
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