82 research outputs found

    Increasing drought effects on five European pines modulate Δ13C-growth coupling along a Mediterranean altitudinal gradient.

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    Climate warming increases vulnerability to drought in Mediterranean water-limited forests. However, we still lack knowledge of the long-term physiological responses of coexisting pine species in these forests regarding their ability to cope with warming-induced drought stress. We investigated spatiotemporal patterns of tree performance for five isohydric pines with partially overlapping ecological niches in the eastern Iberian Peninsula along an altitudinal gradient: Pinus halepensis = P. pinaster ≤ P. nigra ≤ P. sylvestris ≤ P. uncinata. Using indexed tree-ring widths (TRWi) we assessed changes in temporal coherence of radial growth (growth synchrony, âC) over the period 1902-2011 across three elevation belts: low ≈ 1100 m; mid = 1615 m; high = 2020 m. We also examined by mixed modelling whether TRWi showed an increased coupling with leaf-level gas exchange (inferred from indexed carbon isotope discrimination, Δ13Ci) by enhanced stomatal regulation in response to an amplified regional drought stress. Increasingly negative annual water balances (decrease in annual precipitation minus evapotranspiration = -4.8 mm year−1; 1970-2011) prompted more synchronous growth of coexisting pines between low- and mid-elevation belts, with âC rising from 0.25 ± 0.04 (1902-1951) to 0.62 ± 0.05 (1962-2011). This effect was coupled with tighter stomatal regulation at mid-elevation as indicated by high correlations between TRWi and Δ13Ci (>0.60 from the mid-1970s onwards) which resembled those found at low-elevation. Simultaneously, TRWi vs. Δ13Ci uncoupling occurred at the high-elevation belt across species. Weaker growth-climate relationships as elevation increased highlighted the major role of the altitude-dependent thermal gradient in growth responsiveness to drought; however, an intensified Δ13Ci response to spring water availability across elevation belts observed from mid-1970s onwards suggested regional shifts in tree physiological activity linked to earlier seasonal drought impacts. Warming-induced drought stress is spreading to higher altitudes in Iberian pinewoods as multispecies growth is linked to progressively tighter stomatal control of water losses reflected in wood Δ13C

    Jet stream position explains regional anomalies in European beech forest productivity and tree growth

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    The mechanistic pathways connecting ocean-atmosphere variability and terrestrial productivity are well-established theoretically, but remain challenging to quantify empirically. Such quantification will greatly improve the assessment and prediction of changes in terrestrial carbon sequestration in response to dynamically induced climatic extremes. The jet stream latitude (JSL) over the North Atlantic-European domain provides a synthetic and robust physical framework that integrates climate variability not accounted for by atmospheric circulation patterns alone. Surface climate impacts of north-south summer JSL displacements are not uniform across Europe, but rather create a northwestern-southeastern dipole in forest productivity and radial-growth anomalies. Summer JSL variability over the eastern North Atlantic-European domain (5-40E) exerts the strongest impact on European beech, inducing anomalies of up to 30% in modelled gross primary productivity and 50% in radial tree growth. The net effects of JSL movements on terrestrial carbon fluxes depend on forest density, carbon stocks, and productivity imbalances across biogeographic regions

    Aged but withstanding: Maintenance of growth rates in old pines is not related to enhanced water-use efficiency

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    Growth of old trees in cold-limited forests may benefit from recent climate warming and rising atmospheric CO2 concentrations (ca) if age-related constraints do not impair wood formation. To test this hypothesis, we studied old Mountain pine trees at three Pyrenean high-elevation forests subjected to cold-wet (ORD, AIG) or warmer-drier (PED) conditions. We analyzed long-term trends (1450–2008) in growth (BAI, basal area increment), maximum (MXD) and minimum (MID) wood density, and tree-ring carbon (δ13C) and oxygen (δ18O) isotope composition, which were used as proxies for intrinsic water-use efficiency (iWUE) and stomatal conductance (gs), respectively. Old pines showed positive (AIG and ORD) or stable (PED) growth trends during the industrial period (since 1850) despite being older than 400 years. Growth and wood density covaried from 1850 onwards. In the cold-wet sites (AIG and ORD) enhanced photosynthesis through rising ca was likely responsible for the post-1850 iWUE improvement. However, uncoupling between BAI and iWUE indicated that increases in iWUE were not responsible for the higher growth but climate warming. A reduction in gs was inferred from increased δ18O for PED trees from 1960 onwards, the warmest site where the highest iWUE increase occurred (34%). This suggests that an emergent drought stress at warm-dry sites could trigger stomatal closure to avoid excessive transpiration. Overall, carbon acquisition as lasting woody pools is expected to be maintained in aged trees from cold and high-elevation sites where old forests constitute unique long-term carbon reservoirs.We are very grateful to several projects financed by “Organismo Autónomo de Parques Nacionales” (projects 12/2008 387/2011). E.G. was funded by a Juan de la Cierva post-doctoral research contract (FJCI-2014-19615, MEC, Spain). Spanish (AMB95-0160, CGL2011-26654) and EU projects ISONET (contract EV K2-2001-00237) and MILLENNIUM (017008–2) also supported this study by contributing additional datasets

    What drives growth of Scots pine in continental Mediterranean climates: drought, low temperatures or both?

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    Scots pine forests subjected to continental Mediterranean climates undergo cold winter temperatures and drought stress. Recent climatic trends towards warmer and drier conditions across the Mediterranean Basin might render some of these pine populations more vulnerable to drought-induced growth decline at the Southernmost limit of the species distribution. We investigated how cold winters and dry growing seasons drive the radial growth of Scots pine subject to continental Mediterranean climates by relating growth to climate variables at local (elevational gradient) and regional (latitudinal gradient) scales. Local climate-growth relationships were quantified on different time scales (5-, 10- and 15-days) to evaluate the relative role of elevation and specific site characteristics. A negative water balance driven by high maximum temperatures in June (low-elevation sites) and July (high-elevation sites) was the major constraint on growth, particularly on a 5- to 10-day time scale. Warm nocturnal conditions in January were associated with wider rings at the high-elevation sites. At the regional scale, Scots pine growth mainly responded positively to July precipitation, with a stronger association at lower elevations and higher latitudes. January minimum temperatures showed similar patterns but played a secondary role as a driver of tree growth. The balance between positive and negative effects of summer precipitation and winter temperature on radial growth depends on elevation and latitude, with low-elevation populations being more prone to suffer drought and heat stress; whereas, high-elevation populations may be favoured by warmer winter conditions. This negative impact of summer heat and drought has increased during the past decades. This interaction between climate and site conditions and local adaptations is therefore decisive for the future performance and persistence of Scots pine populations in continental Mediterranean climates. Forecasting changes in the Scots pine range due to climate change should include this site-related information to obtain more realistic predictions, particularly in Mediterranean rear-edge areas

    Transcriptomic Correlates of Immunologic Activation in Head and Neck and Cervical Cancer

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    © 2021 Saiz-Ladera, Baliu-Piqué, Cimas, Manzano, García-Barberán, Camarero, Hinojal, Pandiella, Győrffy, Stewart, Cruz-Hernández, Pérez-Segura and Ocana.Targeting the immune system has emerged as an effective therapeutic strategy for the treatment of various tumor types, including Head and Neck Squamous Cell Carcinoma (HNSCC) and Non-small-Cell Lung Cancer (NSCLC), and checkpoint inhibitors have shown to improve patient survival in these tumor types. Unfortunately, not all cancers respond to these agents, making it necessary to identify responsive tumors. Several biomarkers of response have been described and clinically tested. As of yet what seems to be clear is that a pre-activation state of the immune system is necessary for these agents to be efficient. In this study, using established transcriptomic signatures, we identified a group of gene combination associated with favorable outcome in HNSCC linked to a higher presence of immune effector cells. CD2, CD3D, CD3E, and CXCR6 combined gene expression is associated with improved outcome of HNSCC patients and an increase of infiltrating immune effector cells. This new signature also identifies a subset of cervical squamous cell carcinoma (CSCC) patients with favorable prognosis, who show an increased presence of immune effector cells in the tumor, which outcome shows similarities with the HP-positive HNSCC cohort of patients. In addition, CD2, CD3D, CD3E, and CXCR6 signature is able to predict the best favorable prognosis in terms of overall survival of CSSC patients. Of note, these findings were not reproduced in other squamous cell carcinomas like esophageal SCC or lung SCC. Prospective confirmatory studies should be employed to validate these findings.This work has been supported by Instituto de Salud Carlos III (PI16/01121 and PI19/00808), ACEPAIN; Diputación de Albacete, CIBERONC and CRIS Cancer Foundation (to AO). Ministry of Economy and Competitiveness of Spain (BFU2015-71371-R), the Instituto de Salud Carlos III through the Spanish Cancer Centers Network Program (RD12/0036/0003) and CIBERONC, the scientific foundation of the AECC and the CRIS Foundation (to AP). The work carried out in our laboratories receive support from the European Community through the regional development funding program (FEDER)

    SilvAdapt.Net: A Site-Based Network of Adaptive Forest Management Related to Climate Change in Spain

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    [EN] Adaptive forest management (AFM) is an urgent need because of the uncertainty regarding how changes in the climate will affect the structure, composition and function of forests during the next decades. Current research initiatives for the long-term monitoring of impacts of silviculture are scattered and not integrated into research networks, with the consequent losses of opportunities and capacity for action. To increase the scientific and practical impacts of these experiences, it is necessary to establish logical frameworks that harmonize the information and help us to define the most appropriate treatments. In this context, a number of research groups in Spain have produced research achievements and know-how during the last decades that can allow for the improvement in AFM. These groups address the issue of AFM from different fields, such as ecophysiology, ecohydrology and forest ecology, thus resulting in valuable but dispersed expertise. The main objective of this work is to introduce a comprehensive strategy aimed to study the implementation of AFM in Spain. As a first step, a network of 34 experimental sites managed by 14 different research groups is proposed and justified. As a second step, the most important AFM impacts on Mediterranean pines, as one of the most extended natural and planted forest types in Spain, are presented. Finally, open questions dealing with key aspects when attempting to implement an AFM framework are discussed. This study is expected to contribute to better outlining the procedures and steps needed to implement regional frameworks for AFM.A.J. Molina is beneficiary of an "APOSTD" fellowship (APOSTD/2019/111) funded by the Generalitat Valenciana. M. Moreno-de las Heras is beneficiary of a Serra Hunter fellowship (UB-LE-9055) funded by the Generalitat de Catalunya. F.J. Ruiz-Gomez is supported by a postdoctoral fellowship of the Junta de Andalucia (Sevilla, Spain), and the European Social Fund 2014-2020 Program (DOC_0055). The authors received national and international funding through the following projects: SILVADAPT.NET (RED2018-102719-T), ESPECTRAMED (CGL2017-86161-R), Life-FOREST CO2 (LIFE14 CCM/ES/001271), ALTERACLIM (CGL2015-69773-C2-1-P), INERTIA (PID2019-111332RB-C22-BDV), CEHYRFO-MED (CGL2017-86839-C3-2-R), DEHESACLIM (IB16185), RESILIENTFORESTS (LIFE17 CCA/ES/000063), Rhysotto (PID2019-106583RB-I00), AGL2017-83828C2-2-R, RTI2018-096884-B-C31, ESPAS (CGL2015-65569-R), and caRRRascal (RTI2018-095037-B-I00).Molina Herrera, A.; Navarro Cerrillo, R.; Pérez-Romero, J.; Alejano, R.; Bellot, JF.; Blanco, JA.; Camarero, JJ.... (2021). SilvAdapt.Net: A Site-Based Network of Adaptive Forest Management Related to Climate Change in Spain. Forests. 12(12):1-27. https://doi.org/10.3390/f12121807127121

    Definite and indeterminate nonalcoholic steatohepatitis share similar clinical features and prognosis: A longitudinal study of 1893 biopsy-proven nonalcoholic fatty liver disease subjects

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    [Background and Aim] Histological score systems may not fully capture the essential nonalcoholic steatohepatitis (NASH) features, which is one of the leading causes of screening failure in clinical trials. We assessed the NASH distribution and its components across the fibrosis stages and their impact on the prognosis and their relationship with the concept of metabolic-associated fatty liver disease (MAFLD).[Methods] Spanish multicenter study including 1893 biopsy-proven nonalcoholic fatty liver disease (NAFLD) patients from HEPAmet registry. NASH was diagnosed by NAS score ≥4 (including steatosis, ballooning and lobular inflammation) and fibrosis by Kleiner score. The presence of MAFLD was determined. Progression to cirrhosis, first episode of decompensated cirrhosis and death were collected during the follow-up (4.7 ± 3.8 years).[Results] Fibrosis was F0 34.3% (649/1893), F1 27% (511/1893), F2 16.5% (312/1893), F3 15% (284/1893) and F4 7.2% (137/1893). NASH diagnosis 51.9% (982/1893), and its individual components (severe steatosis, ballooning and lobular inflammation), increased from F0 (33.6%) to F2 (68.6%), and decreased significantly in F4 patients (51.8%) (P = .0001). More than 70% of non-NASH patients showed some inflammatory activity (ballooning or lobular inflammation), showing a similar MAFLD rate than NASH (96.2% [945/982] vs. 95.2% [535/562]) and significantly higher than nonalcoholic fatty liver (NAFL) subjects (89.1% [311/349]) (P < .0001). Progression to cirrhosis was similar between NASH (9.5% [51/539]) and indeterminate NASH (7.9% [25/316]), and higher than steatosis (5% [14/263]) (logRank 8.417; P = .015). Death and decompensated cirrhosis were similar between these.[Conclusions] The prevalence of steatohepatitis decreased in advanced liver disease. However, most of these patients showed some inflammatory activity histologically and had metabolic disturbances. These findings should be considered in clinical trials whose main aim is to prevent cirrhosis progression and complications, liver transplant and death.This project has been partially funded by the ‘Consejería de Salud de la Junta de Andalucía’ (PI-0075-2014) and the ‘Spanish Ministry of Economy, Innovation and Competition, Instituto de Salud Carlos III’ (PI19/01404, PI16/01842, PI17/00535 and GLD19/00100).Peer reviewe

    Home enteral nutrition in Spain: NADYA registry 2010

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    Objetivos: Describir los resultados del registro de nutrición enteral domiciliaria (NED) del grupo NADYASENPE del año 2010. Material y métodos: Se recopilaron los datos introducidos en el registro desde el 1 de enero al 31 de diciembre de 2010. Resultados: Se registraron 6.591 pacientes (51% varones) con 6.688 episodios de NED, procedentes de 32 hospitales. La edad media en los menores de 14 años (4%) fue de 1 ± 2 años (m ± DS) y de 69,9 ± 17,8 en los mayores de 14 años. El 76% de los pacientes recibieron la NED por un tiempo superior a 2 años. La patología más prevalente fue la neurológica 42%, seguida de la neoplasia 28% (en su mayoría cáncer de cabeza y cuello 18%). La información referente a la vía de acceso sólo se recogió en 626 casos (9,4%), el 51% de los pacientes utilizaron sonda nasogástrica, 27% gastrostomías, 10% vía oral y 3% yeyunostomías. Sólo 251 episodios finalizaron a lo largo del año, siendo el motivo más frecuente el fallecimiento del paciente en el 57% de los casos y el paso a la alimentación oral en el 14%. El 29% de los pacientes presentaban una actividad limitada y el 39% estaba confinado en cama/ sillón. El 68% de los adultos requerían ayuda total o parcial. El suministro del producto se realizó desde el hospital o la farmacia de referencia en el 63% y 34%, respectivamente. El suministro del material fungible se realizó desde el hospital o atención primaria en el 83% y 16%, respectivamente. Conclusiones: Los resultados obtenidos en el registro de NED del año 2010 muestran características muy similares a las recogidas en los años previos en cuanto al número y características de los pacientes registrados. Seguimos encontrando problemas en la recogida de datos relativos a la vía de acceso y finalización de los episodiosObjective: To describe the results of the home enteral nutrition (HEN) registry of the NADYA-SENPE group in 2010. Material and methods: We retrieved the data of the patients recorded from January 1st to December 31st 2010. Results: We registered 6,591 patients (51% males) with 6,688 episodes of HEN, from 32 hospitals. Mean age in those younger than 14 yr (4%) was 1 ± 2 yrs (m ± SD) and 69,9 ± 17,8 yrs in those older than 14 yr. The length of HEN was longer than 2 yrs in 76% of the patients. The most frequent underlying disease was neurological disorders 42%, followed by cancer 28% (mostly head and neck cancer 18%). We had information related to the enteral access route in only 626 cases (9,4%), 51% of them used nasogastric tubes, 27% gastrostomies, 10% oral route and 3% jejunostomies. Only 251 episodes were closed during the year, mostly due to patient death 57% and progress to oral diet 14%. The activity level was limited in 29% of the patients and 39% of them were bed- or chairridden. Total or partial help was needed by 68% of the patients. The hospitals and the private pharmacies delivered the enteral formula in 63% and 34% of the cases, respectively. The hospitals and the primary care centres delivered the disposables in 83% and16% of the cases, respectively. Conclusions: The results of the 2010 HEN registry are similar to those published in previous years regarding the number and characteristics of the patients. We continue finding problems in the entrance of data referred to the enteral access route and the closing of the episode
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