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1.
Plants (Basel) ; 13(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38891309

RESUMO

Climate-change-related increases in the frequency and intensity of heatwaves affect viticulture, leading to losses in yield and grape quality. We assessed whether canopy-architecture manipulation mitigates the effects of summer stress in a Mediterranean vineyard. The Vitis vinifera L variety Muscat of Alexandria plants were monitored during 2019-2020. Two canopy shoot-positioning treatments were applied: vertical shoot positioning (VSP) and modulated shoot positioning (MSP). In MSP, the west-side upper foliage was released to promote partial shoot leaning, shading the clusters. Clusters were sampled at pea size (PS), veraison (VER), and full maturation (FM). Measurements included rachis anatomy and hydraulic conductance (Kh) and aquaporins (AQP) and stress-related genes expression in cluster tissues. The results show significant seasonal and interannual differences in Kh and vascular anatomy. At VER, the Kh of the rachis and rachis+pedicel and the xylem diameter decreased but were unaffected by treatments. The phloem-xylem ratio was either increased (2019) or reduced (2020) in MSP compared to VSP. Most AQPs were down-regulated at FM in pedicels and up-regulated at VER in pulp. A potential maturation shift in MSP was observed and confirmed by the up-regulation of several stress-related genes in all tissues. The study pinpoints the role of canopy architecture in berry-water relations and stress response during ripening.

2.
Sci Total Environ ; 947: 173619, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38825208

RESUMO

The globalization in plant material trading has caused the emergence of invasive pests in many ecosystems, such as the alder pathogen Phytophthora ×alni in European riparian forests. Due to the ecological importance of alder to the functioning of rivers and the increasing incidence of P. ×alni-induced alder decline, effective and accessible decision tools are required to help managers and stakeholders control the disease. This study proposes a Bayesian belief network methodology to integrate diverse information on the factors affecting the survival and infection ability of P. ×alni in riparian habitats to help predict and manage disease incidence. The resulting Alder Decline Network (ADnet) management tool integrates information about alder decline from scientific literature, expert knowledge and empirical data. Expert knowledge was gathered through elicitation techniques that included 19 experts from 12 institutions and 8 countries. An original dataset was created covering 1189 European locations, from which P. ×alni occurrence was modeled based on bioclimatic variables. ADnet uncertainty was evaluated through its sensitivity to changes in states and three scenario analyses. The ADnet tool indicated that mild temperatures and high precipitation are key factors favoring pathogen survival. Flood timing, water velocity, and soil type have the strongest influence on disease incidence. ADnet can support ecosystem management decisions and knowledge transfer to address P. ×alni-induced alder decline at local or regional levels across Europe. Management actions such as avoiding the planting of potentially infected trees or removing man-made structures that increase the flooding period in disease-affected sites could decrease the incidence of alder disease in riparian forests and limit its spread. The coverage of the ADnet tool can be expanded by updating data on the pathogen's occurrence, particularly from its distributional limits. Research on the role of genetic variability in alder susceptibility and pathogen virulence may also help improve future ADnet versions.


Assuntos
Alnus , Teorema de Bayes , Doenças das Plantas/microbiologia , Doenças das Plantas/estatística & dados numéricos , Phytophthora , Ecossistema , Europa (Continente)/epidemiologia , Florestas , Conservação dos Recursos Naturais
3.
Minerva Med ; 113(3): 449-459, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35156787

RESUMO

There is no justification for a therapeutic nihilism in clinical practice because current management (pharmacological and non-pharmacological) of the patients with chronic obstructive pulmonary disease according to treatable traits is effective in decreasing their respiratory symptoms, increasing their exercise tolerance and capacity, improving their quality of life, preventing (and treating) many of their exacerbations and decreasing their mortality.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Progressão da Doença , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia
4.
Front Plant Sci ; 7: 1170, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27570527

RESUMO

Western Iberia has recently shown increasing frequency of drought conditions coupled with heatwave events, leading to exacerbated limiting climatic conditions for plant growth. It is not clear to what extent wood growth and density of agroforestry species have suffered from such changes or recent extreme climate events. To address this question, tree-ring width and density chronologies were built for a Pinus pinaster stand in southern Portugal and correlated with climate variables, including the minimum, mean and maximum temperatures and the number of cold days. Monthly and maximum daily precipitations were also analyzed as well as dry spells. The drought effect was assessed using the standardized precipitation-evapotranspiration (SPEI) multi-scalar drought index, between 1 to 24-months. The climate-growth/density relationships were evaluated for the period 1958-2011. We show that both wood radial growth and density highly benefit from the strong decay of cold days and the increase of minimum temperature. Yet the benefits are hindered by long-term water deficit, which results in different levels of impact on wood radial growth and density. Despite of the intensification of long-term water deficit, tree-ring width appears to benefit from the minimum temperature increase, whereas the effects of long-term droughts significantly prevail on tree-ring density. Our results further highlight the dependency of the species on deep water sources after the juvenile stage. The impact of climate changes on long-term droughts and their repercussion on the shallow groundwater table and P. pinaster's vulnerability are also discussed. This work provides relevant information for forest management in the semi-arid area of the Alentejo region of Portugal. It should ease the elaboration of mitigation strategies to assure P. pinaster's production capacity and quality in response to more arid conditions in the near future in the region.

5.
Sci Rep ; 5: 15110, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26461978

RESUMO

Extreme drought events and plant invasions are major drivers of global change that can critically affect ecosystem functioning and alter ecosystem-atmosphere exchange. Invaders are expanding worldwide and extreme drought events are projected to increase in frequency and intensity. However, very little is known on how these drivers may interact to affect the functioning and resilience of ecosystems to extreme events. Using a manipulative shrub removal experiment and the co-occurrence of an extreme drought event (2011/2012) in a Mediterranean woodland, we show that native shrub invasion and extreme drought synergistically reduced ecosystem transpiration and the resilience of key-stone oak tree species. Ecosystem transpiration was dominated by the water use of the invasive shrub Cistus ladanifer, which further increased after the extreme drought event. Meanwhile, the transpiration of key-stone tree species decreased, indicating a competitive advantage in favour of the invader. Our results suggest that in Mediterranean-type climates the invasion of water spending species and projected recurrent extreme drought events may synergistically cause critical drought tolerance thresholds of key-stone tree species to be surpassed, corroborating observed higher tree mortality in the invaded ecosystems. Ultimately, this may shift seasonally water limited ecosystems into less desirable alternative states dominated by water spending invasive shrubs.


Assuntos
Clima , Secas , Ecossistema , Plantas Daninhas/fisiologia , Quercus/fisiologia , Água/metabolismo , Transpiração Vegetal/fisiologia , Especificidade da Espécie , Estresse Fisiológico/fisiologia
7.
Funct Plant Biol ; 39(2): 103-115, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32480765

RESUMO

The topology of the xylem network is likely to affect the transport of water, propagation of embolism and plant survival and growth. Few studies have been conducted on the hydraulics of the entire water pathway in trees. We evaluated the hydraulic connections from roots to branches in a mature Quercus suber L. tree, through sap flow responses upon branch severing. Sap flow was recorded in branches, stem and roots by the heat field deformation (HFD) method. Results showed that roots, except for the taproot, were hydraulically connected to all branches, but the rest of the tree (stem, branches and taproot) was highly sectored. In the large roots that showed an integrated response to branch severing, the outer xylem was preferentially connected to the same side branch and the inner xylem to the opposite branch. The hydraulic sectoriality in branches, stem and taproot may be regarded as an adaptive trait to water stress. The integrated hydraulic structure of roots is advantageous under patchy soil conditions, but may allow the spread of root diseases. The HFD sap flow method proved extremely useful to calculate xylem flux connectivity between different organs of a large tree, providing a comprehensive picture of its hydraulic architecture.

8.
Oecologia ; 163(4): 1043-57, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20217141

RESUMO

Combining C flux measurements with information on their isotopic composition can yield a process-based understanding of ecosystem C dynamics. We studied the variations in both respiratory fluxes and their stable C isotopic compositions (delta(13)C) for all major components (trees, understory, roots and soil microorganisms) in a Mediterranean oak savannah during a period with increasing drought. We found large drought-induced and diurnal dynamics in isotopic compositions of soil, root and foliage respiration (delta(13)C(res)). Soil respiration was the largest contributor to ecosystem respiration (R (eco)), exhibiting a depleted isotopic signature and no marked variations with increasing drought, similar to ecosystem respired delta(13)CO(2), providing evidence for a stable C-source and minor influence of recent photosynthate from plants. Short-term and diurnal variations in delta(13)C(res) of foliage and roots (up to 8 and 4 per thousand, respectively) were in agreement with: (1) recent hypotheses on post-photosynthetic fractionation processes, (2) substrate changes with decreasing assimilation rates in combination with increased respiratory demand, and (3) decreased phosphoenolpyruvate carboxylase activity in drying roots, while altered photosynthetic discrimination was not responsible for the observed changes in delta(13)C(res). We applied a flux-based and an isotopic flux-based mass balance, yielding good agreement at the soil scale, while the isotopic mass balance at the ecosystem scale was not conserved. This was mainly caused by uncertainties in Keeling plot intercepts at the ecosystem scale due to small CO(2) gradients and large differences in delta(13)C(res) of the different component fluxes. Overall, stable isotopes provided valuable new insights into the drought-related variations of ecosystem C dynamics, encouraging future studies but also highlighting the need of improved methodology to disentangle short-term dynamics of isotopic composition of R (eco).


Assuntos
Dióxido de Carbono/metabolismo , Secas , Ecossistema , Quercus/metabolismo , Solo/análise , Isótopos de Carbono/análise , Respiração Celular , Fotossíntese , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Portugal , Microbiologia do Solo , Tempo (Meteorologia)
9.
Pharmacol Res ; 61(2): 116-20, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19666121

RESUMO

Chest trauma is frequently followed by pulmonary contusion and sepsis. High mobility group box-1 (HMGB-1) is a late mediator of severe sepsis that has been associated with mortality under experimental conditions. We studied HMGB-1 mRNA expression in patients with lung injury and its relationship with the severity of trauma and survival. A total of 24 consecutive patients with chest trauma referring to the Intensive Care Unit of Messina University Hospital, were enrolled. Lung trauma was established on the basis of chest X-ray and computed tomography. Injury Severity Score (ISS), Revised Trauma Score (RTS) and Glasgow Coma Scale (GCS) were also assessed. Accordingly to these results 6 patients were considered as controls because of no penetrating trauma and low ISS. Blood and broncho-alveolar lavage fluid (BALF) from chest trauma patients were withdrawn at admission and 24h after the beginning of the standard therapeutic protocol. HMGB-1 mRNA increased significantly in blood (r=0.84) and BALF (r=0.87) from patients with trauma and pulmonary contusion and positively correlated with the severity of trauma (based on ISS and RTS) and the final outcome. HMGB-1 protein levels were also elevated in BALF macrophages from severe trauma patients compared to control subjects, furthermore TNF-alpha and its receptor TNFR-1 mRNA levels were also markedly increased in patients with a poor outcome respect to other subjects. Our study suggests that HMGB-1 may be an early indicator of poor clinical outcome in patients with chest trauma.


Assuntos
Proteína HMGB1/metabolismo , Lesão Pulmonar/metabolismo , Adolescente , Adulto , Western Blotting , Líquido da Lavagem Broncoalveolar/química , Estudos de Casos e Controles , Escala de Coma de Glasgow , Proteína HMGB1/genética , Humanos , Escala de Gravidade do Ferimento , Modelos Lineares , Lesão Pulmonar/diagnóstico por imagem , Lesão Pulmonar/mortalidade , Lesão Pulmonar/terapia , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Fator de Necrose Tumoral alfa/genética , Regulação para Cima , Adulto Jovem
10.
Int J Infect Dis ; 14(7): e572-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19892577

RESUMO

INTRODUCTION: Post-neurosurgical nosocomial meningitis has become an important subgroup of bacterial meningitis in the hospital setting. The increase in meningitis caused by multidrug-resistant (MDR) Acinetobacter baumannii has resulted in a significant reduction in available treatment options. CASE REPORT AND LITERATURE REVIEW: We report the case of a 36-year-old man with a complex craniofacial trauma, who developed a nosocomial meningitis due to MDR A. baumannii that was cured by intrathecal colistin. The case is contextualized among all the published cases of Acinetobacter meningitis treated with topical colistin found through a MEDLINE search of the literature. To date, including the present case, eight reported cases of Acinetobacter meningitis have been treated with colistin administered by an intrathecal route and 24 by an intraventricular route. The daily dose of colistin used ranged from 1.6 mg every 24 h to 20 mg every 24 h in adult patients. The median time necessary to obtain cerebrospinal fluid sterilization was 4.1 days, and treatment was always successful even if in two cases Acinetobacter meningitis relapsed. Toxicity probably or possibly related to the topical administration of colistin was noted in five out of the 32 patients. CONCLUSIONS: Topical colistin can be an effective and safe treatment for MDR Acinetobacter meningitis.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/administração & dosagem , Colistina/administração & dosagem , Traumatismos Craniocerebrais/cirurgia , Farmacorresistência Bacteriana Múltipla , Meningites Bacterianas/tratamento farmacológico , Complicações Pós-Operatórias/tratamento farmacológico , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Adulto , Humanos , Injeções Espinhais , Masculino , Meningites Bacterianas/microbiologia , Complicações Pós-Operatórias/microbiologia , Resultado do Tratamento
11.
Tree Physiol ; 28(10): 1545-52, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18708336

RESUMO

To evaluate differences in growth and adaptability of maritime pine (Pinus pinaster Ait.), we studied growth, polycyclism, needle tissue carbon isotope composition (delta(13)C) as an estimate of water-use efficiency (WUE) and survival of seven populations at 10 years of age growing in a performance trial at a provenance test site in Escaroupim, Portugal. Six populations were from relatively high rainfall sites in Portugal and southwestern France (Atlantic group), and one population was from a more arid Mediterranean site in Spain. There were significant differences between some populations in total height, diameter at breast height, delta(13)C of bulk needle tissue, polycyclism and survival. A population from central Portugal (Leiria, on the Atlantic coast) was the tallest and had the lowest delta(13)C. Overall, the variation in delta(13)C was better explained by the mean minimum temperatures of the coldest month than by annual precipitation at the place of origin. Analyses of the relationships between delta(13)C and growth or survival revealed a distinct pattern for the Mediterranean population, with low delta(13)C (and WUE) associated with the lowest growth potential and reduced survival. There were significant negative correlations between delta(13)C and height or survival in the Atlantic group. Variation in polycyclism was correlated with annual precipitation at the place of origin. Some Atlantic populations maintained a high growth potential while experiencing moderate water stress. A detailed knowledge of the relationships between growth, survival and delta(13)C in contrasting environments will enhance our ability to select populations for forestry or conservation.


Assuntos
Carbono/metabolismo , Pinus/crescimento & desenvolvimento , Aclimatação , Isótopos de Carbono , Geografia , Pinus/anatomia & histologia , Pinus/metabolismo , Portugal , Chuva , Água/metabolismo
12.
Rev Port Pneumol ; 13(1): 53-70, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17315090

RESUMO

Pediatric management of complicated pleural effusion (CPE) remains controversial. Different approaches include antibiotics and chest tube drainage alone or the use of fibrinolitics, videothorascoscopy (VTC) and surgical decortication through thoracotomy. The aim of the present study was to review, evaluate and update technical approach to CPE. We retrospectively reviewed the clinical files of children admitted to the Pediatric Respiratory Ward between 1992 and 2003 with the diagnosis of CPE. Twenty-five patients were included [15 male (60%)]. Mean (+/-SD) age was 37,4 (+/-37,0) months. Bacteria were identified in 17/25 (68%) [S. aureus in 6/17 (35%), St. pneumoniae in 5/17 (29%)], 16/17 (94%)in the pleural fluid. Twenty-five children were treated with antibiotics and thoracocentesis (100%). Chest tube drainage was required in 22/25 (88%) with mean (+/-DP) duration of 14,2 (+/-7,8) days. Fibrinolitics were employed in 1 only case and surgical decortication in 11/25 (44%). One patient (4%) was submitted to primary VTC. Median length of stay was 30,4 (+/-15,1) days and no deaths were recorded. Center skills in CPE management are critical on the choice of the technique and the timing of approach. This seems to influence immediate prognosis.


Assuntos
Derrame Pleural/complicações , Derrame Pleural/terapia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Derrame Pleural/etiologia , Pneumonia Bacteriana/complicações , Estudos Retrospectivos
13.
J Oral Implantol ; 33(6): 371-82, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18240798

RESUMO

Bisphosphonates (BP) are nonhormonal medications used in the treatment of various bone malignancies and metabolic conditions. Since 2003, there have appeared a significant and growing number of articles in the worldwide medical and dental literature describing the complication of an osteonecrosis of the jaws associated with the intravenous and, most recently, the oral form of BP medication that has been refractory to any definitive form of treatment. The authors have successfully managed 2 patients taking the oral form of BP with adjunctive treatment using platelet-rich plasma (PRP), and in one case with hyperbaric oxygen (HBO). We were able to obtain complete remission in each case, which is defined as resolution of pain and complete closure of exposed bone in the jaws. The purpose of this report is to describe a treatment protocol and the rationale for using PRP and HBO to obtain complete remission of this new pathologic condition.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Oxigenoterapia Hiperbárica , Doenças Maxilomandibulares/terapia , Osteonecrose/terapia , Plasma Rico em Plaquetas , Actinomicose/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Alendronato/efeitos adversos , Feminino , Humanos , Doenças Maxilomandibulares/induzido quimicamente , Doenças Maxilomandibulares/patologia , Masculino , Osteonecrose/induzido quimicamente , Osteonecrose/patologia
14.
New Phytol ; 172(2): 330-46, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16995920

RESUMO

Temporal dynamics in carbon isotope ratios of ecosystem respiration (delta13C(R)) were evaluated on hourly, daily and annual timescales in a Mediterranean woodland. Emphasis was given to the periods of transition from wet to dry season and vice versa, when the system turns from a net carbon sink to a source. The constancy of nocturnal delta13C(R) was tested. The relationship between delta13C(R) (determined through Keeling plots) and environmental factors was evaluated through time-lag analysis. Delta13C(R) exhibited high annual variation (> 7). During the transition periods, delta13C(R) correlated significantly with factors influencing photosynthetic discrimination, soil respiration, and whole-canopy conductance. Time-lags differed between below- and above-ground variables, and between seasons. A shift in regression parameters with environmental factors indicated seasonal differences in ecosystem responsiveness (e.g. temperature acclimation). Delta13C(R) exhibited substantial nocturnal enrichment (> 4) from dusk to dawn. These data indicate pronounced short-term dynamics in delta13C(R) at hourly to daily timescales and a modulated response to environmental drivers. Substantial short-term changes in nocturnal delta13C(R) may have important implications for the sampling protocols of nocturnal Keeling plots.


Assuntos
Dióxido de Carbono/metabolismo , Ecossistema , Quercus/metabolismo , Árvores/metabolismo , Isótopos de Carbono , Ritmo Circadiano , Região do Mediterrâneo , Estações do Ano , Fatores de Tempo
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