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In the context of future climate change new habitats will be threatened and unique species will be forced to develop different strategies to survive. Saxifraga longifolia Lapeyr. is an endemic species from the Pyrenees with a very particular habitat. We explored the capacity and strategies of S. longifolia plants to face different severities of drought stress under both natural conditions and controlled water stress followed by a re-watering period of 20 days. Our results showed a role for abscisic acid (ABA), salicylic acid (SA) and cytokinins (CKs) in plant survival from drought stress, and as the stress increased, ABA lost significance and SA appeared to be more associated with the response mechanisms. Moreover, photo-oxidative stress markers revealed that both xanthophyll cycles played a photoprotection role with a stronger participation of the lutein epoxide cycle as the stress was more intense. Severe drought decreased the maximum efficiency of photosystem II (Fv /Fm ) below 0.45, being this the limit to survive upon rewatering. Overall, our results proved different strategies of S. longifolia plants to cope with drought stress and suggested a Fv /Fm threshold to predict plant survival in high-mountain environments.

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si lo hubiere, y los autores pertenecientes a la UAM, Some patients with COVID-19 pneumonia develop an associated cytokine storm syndrome that aggravates the pulmonary disease. These patients may benefit of anti-inflammatory treatment. The role of colchicine in hospitalized patients with COVID-19 pneumonia and established hyperinflammation remains unexplored. In a prospective, randomized controlled, observer-blinded endpoint, investigator-initiated trial, 240 hospitalized patients with COVID-19 pneumonia and established hyperinflammation were randomly allocated to receive oral colchicine or not. The primary efficacy outcome measure was a composite of non-invasive mechanical ventilation (CPAP or BiPAP), admission to the intensive care unit, invasive mechanical ventilation requirement or death. The composite primary outcome occurred in 19.3% of the total study population. The composite primary outcome was similar in the two arms (17% in colchicine group vs. 20.8% in the control group; p = 0.533) and the same applied to each of its individual components. Most patients received steroids (98%) and heparin (99%), with similar doses in both groups. In this trial, including adult patients with COVID-19 pneumonia and associated hyperinflammation, no clinical benefit was observed with short-course colchicine treatment beyond standard care regarding the combined outcome measurement of CPAP/BiPAP use, ICU admission, invasive mechanical ventilation or death

Oxidative stress and hormonal regulation are hallmarks of a/biotic stress responses in plants. However, little is known about their linkage with whole-organismal mortality in long-lived species. Here, we examined the validity of photo-oxidative stress markers and stress-related phytohormones as predictive proxies of mortality risk in the perennial herb Plantago lanceolata. Capitalizing on its broad ecological niche, we examined photo-oxidative stress markers (Fv/Fm ratio, contents of chlorophylls, carotenoids, and tocochromanols, and the extent of lipid peroxidation) and stress-related phytohormones (ABA, salicylic acid and jasmonates contents) as proxies of mortality in three populations of sub-tropical and Mediterranean habitats: Virginia (VA, U.S.A.), Catalonia (CAT, Spain), and Queensland (QLD, Australia). Stress markers were measured together with the vital rates of survival, growth, and reproduction on a total of 279 individuals. Stress marker data were collected during the summer and death/survival was monitored after two and four months. Whole-organism mortality was similarly high in both sub-tropical non-native populations (ca. 30 % after a drought in VA and QLD), but lower in the native population (ca. 10 % in CAT). The contents of antioxidants (lutein, zeaxanthin, β-carotene) and the de-epoxidation state of the xanthophyll cycle (DPS) were good proxies of mortality risk in VA and QLD. DPS and all carotenoid contents per unit of chlorophyll were lower four months in advance in dead than in alive plants in VA and QLD, thus suggesting reduced photoprotective capacity increased the mortality risk in non-native populations. We show that whole-organismal mortality in P. lanceolata is associated with a reduced capacity to enhance photoprotection under abiotic stress conditions. The validity of various stress markers as predictive proxies of mortality risk is discussed.

Mastic trees (Pistacia lentiscus L.) are dioecious perennial plants that are highly adapted to Mediterranean climates but display a high sensitivity to winter periods. In order to understand how sex, leaf phenology and ecological context could condition sensitivity to winter and associated mechanisms to acclimate to these conditions, photoinhibition and photo-oxidative stress markers were examined in mastic trees (P. lentiscus) from a natural population growing in the Garraf Natural Park for a consecutive 12-month period (seasonal study), as well as in three populations naturally growing in the Montseny Natural Park, including the highest altitudes described for this species, during winter (altitudinal study). Results from these studies indicate that both the winter period and higher elevation influenced the degree of photoinhibition, but this was not conditioned by sex. In fact, winter photoinhibition occurred transiently even though it was accompanied by chlorophyll loss and malondialdehyde contents. Stress acclimation was achieved through biochemical adjustments in chloroplasts, characterized by anthocyanin shielding, increased de-epoxidation state of the xanthophyll cycle as well as tocopherol accumulation, and phenological adaptations, the latter allowing a complete resetting of the physiological performance of leaves. Moreover, although females showed higher lipid peroxidation than males during the coldest winter months, at the highest elevation and during flowering in spring, this oxidative stress was mild and transient with no negative consequences for the physiology of plants. It is concluded that evergreen mastic trees acclimate to winter conditions and higher elevations by activation of antioxidant defenses together with phenological adjustments, altogether playing a crucial role in plant survival. Sexual dimorphism in mastic trees appears as a relevant factor when considering sensitivity to photo-oxidative stress in winter and altitudinal conditions.

High-mountain ecosystems are biodiversity hotspots, providing habitats that shelter a great variety of unique species. Climate change is increasing the severity and recurrence of drought events, potentially endangering many species. We studied the distribution of a monocarpic perennial plant, Saxifraga longifolia and evaluated altitudinal changes in leaf physiological performance, with a particular emphasis on trade-offs and drought vulnerability in nine natural populations. Drought vulnerability of the studied populations covering almost the entire distribution range of the species was considered taking into account both ecological and physiological markers. The distribution of S. longifolia outside the Pyrenees was limited to the high eastern and North-west mountains of the Iberian Peninsula, constituting geographically highly isolated populations. We found that trade-offs between the activation of defense responses against abiotic and biotic stresses occur in this species, with populations occurring at high elevation showing less sensitivity to drought stress but higher endogenous contents of biotic defensive compounds. Furthermore, drought stress appeared to be a key factor in the distribution of this species, with populations growing at lowest elevations being the most exposed to the potential negative effects of climate change. It is concluded that, despite S. longifolia has developed complex mechanisms to adapt to the harsh environmental conditions of high-mountain ecosystems, global change is threatening its survival, most particularly in the regions most exposed to drought events.

Jasmonates are widely found in the plant kingdom and play a key role in both plant biotic and abiotic defense and plant development. Jasmonates activity under abiotic stress conditions have been extensively investigated in model plants, but little is known about the bioactive forms and their functions in non-model species, particularly in plants growing in their natural environment. Here, we performed a jasmonate profiling approach to unravel changes in the specific jasmonate signature of leaves as a function of environmental conditions, including the measurement of both free and conjugated forms of jasmonates by UHPLC–MS/MS, during the summer and autumn in Saxifraga longifolia plants growing in their natural habitat in the Pyrenees. We evaluated the climatological factors governing specific jasmonate signatures and the correlation between jasmonate accumulation and leaf morphology, PSII efficiency and pigment accumulation, including anthocyanins, chlorophylls and carotenoids. The results showed a jasmonate profiling characterized by an accumulation of free jasmonic acid and its precursor, 12-oxo-phytodienoic acid, with the amino acid conjugated forms being much less abundant. Among amino acid conjugates, jasmonoyl-isoleucine, jasmonoyl-valine and jasmonoyl-phenylalanine were the most abundant forms. Contents of 12-oxo-phytodienoic acid decreased, while those of free jasmonic acid increased during summer drought stress events. The five amino acid conjugated forms did respond similarly to environmental changes with progressive decreases from summer to autumn, but irrespective of drought events. Endogenous contents of free jasmonic acid correlated positively with those of anthocyanins. Furthermore, exogenous jasmonate applications on leaves increased anthocyanin contents, thus confirming a link between jasmonates and anthocyanin accumulation in S. longifolia plants.

Background and Aims Monocarpic plants are those that flower, produce seeds and then die. Although most monocarpic plants are annual or biennial, some of them are perennial. However, relatively little is known regarding the biology of monocarpic perennials. Pyrenean saxifrage (Saxifraga longifolia) is a monocarpic perennial that is well adapted to high-mountain ecosystems. Here, we evaluated altitudinal changes in clonality in various populations growing in their natural habitat with particular emphasis on the physiological costs of clonal growth. Methods We assessed the percentage of clonal plants in nine populations growing in their natural habitat, as well as the plant stress response of clonal and non-clonal plants, in terms of photoprotection and accumulation of stress-related phytohormones, in a 3-year study at Las Blancas (2100 m a.s.l.). We also evaluated the influence of plant size on the activation of defensive responses to biotic and abiotic stresses. Key Results We found that 12 % of Pyrenean saxifrage plants growing at the highest altitudes (2100 m a.s.l.) produced lateral rosettes which survived the flowering of the main rosette and shared the same axonomorphic root, thus escaping monocarpic senescence. This clonal growth did not worsen the physiological performance of plants growing at this altitude. Furthermore, increased plant size did not negatively affect the physiology of plants, despite adjustments in endogenous stress-related phytohormones. In contrast, maturity led to rapid physiological deterioration of the rosette, which was associated with monocarpic senescence. Conclusions This study shows that the evolution of clonality has allowed Pyrenean saxifrage to survive harsh environmental conditions and it provides evidence that harsh environments push plant species to their limits in terms of life form and longevity.

[spa] Los ecosistemas de alta montaña son puntos calientes de biodiversidad, ya que proporcionan hábitats que albergan una gran variedad de especies únicas. El clima por encima del límite forestal se caracteriza por tener temperaturas extremas, elevada radiación solar y fuertes vientos, y se espera que las condiciones ambientales sean aún más duras en el marco actual del cambio climático, lo que aumentará la gravedad y la recurrencia de los eventos de sequía y pondrá en peligro a muchas especies. En este contexto, la capacidad fisiológica para responder a estas condiciones ambientales severas determinará el éxito de la supervivencia de las especies. Exploramos la influencia de la altitud y la sequía en una planta perenne, monocárpica y endémica de los Pirineos, Saxifraga longifolia, revelando adaptaciones para hacer frente al escenario de cambio climático actual de alta montaña. Evaluamos la acumulación de pigmentos, la activación de los sistemas antioxidantes y los cambios en el perfil hormonal bajo condiciones naturales y controladas. Investigamos las estrategias para hacer frente al aumento de la altitud y a las condiciones ambientales del verano alpino, con especial énfasis en las respuestas al estrés de la sequía tanto en condiciones naturales como controladas. Las condiciones de sequía activaron mecanismos de fotoprotección y antioxidantes, activando los ciclos de xantofilas (VAZ y L/Lx) y promoviendo la acumulación de antocianinas y tocoferoles. Los ajustes fisiológicos a la sequía se debieron principalmente a las acciones combinadas del ácido abscísico, el ácido salicílico y las citoquininas. Además, encontramos que la clonalidad y la latencia de las semillas pueden servir como mecanismos para prolongar la longevidad en poblaciones que se encuentran a gran altitud. Además, las plantas mostraron un endurecimiento por congelación al modificar la morfología de la hoja y la composición de la antena de captación de luz de los fotosistemas, lo que garantiza la tolerancia a la congelación durante las condiciones invernales. Concluimos que a pesar de que S. longifolia ha desarrollado mecanismos complejos que operan a nivel celular, de planta entera y poblacional para adaptarse a las duras condiciones ambientales que prevalecen actualmente en los ecosistemas de alta montaña en los Pirineos, los eventos de sequía podrían conducir a un aumento de la mortalidad dentro del marco del cambio global., [eng] High-mountain ecosystems are hotspots for biodiversity, providing habitats that shelter a great variety of unique species. Climate above the timberline is characterized by extremes in temperature, wind and solar radiation, and environmental conditions are expected to be even harsher in the current framework of climate change particularly increasing the severity and recurrence of drought events, potentially endangering many species. In this context, the physiological capacity to respond to these severe environmental conditions will determine their survival success. We explored the influence of altitude and drought in a monocarpic perennial endemic from the Pyrenees, Saxifraga longifolia, unveiling high-mountain adaptations to the current climate change scenario. We assessed pigment accumulation, activation of antioxidant systems and changes in hormonal profiling under both natural and controlled conditions. We explored the strategies to face increasing altitude and contrasting environmental conditions during the summer, with an emphasis on drought stress responses under both natural and controlled conditions. Drought conditions triggered photoprotection and antioxidant mechanisms, activating both xanthophyll (VAZ and L/Lx) cycles, and promoting anthocyanin and tocopherol accumulation. Physiological adjustments to drought were driven mainly by a cross- talk between abscisic acid, salicylic acid and cytokinins. Furthermore, we found that clonality and seed dormancy may serve as mechanisms to prolong longevity in populations occurring at high elevation. In addition, plants showed frost pre-hardening by modifying leaf morphology and photosystems light harvesting antenna composition, ensuring freezing tolerance under winter conditions. We conclude that despite S. longifolia has developed complex mechanisms that operate at the cellular, whole-plant and population levels to adapt to the harsh environmental conditions currently prevailing in high-mountain ecosystems in the Pyrenees, drought events could lead to an increased mortality in the framework of global change.

El centro de salud Parte Vieja/Alde Zaharra de Donostia- San Sebastian atiende una poblacion de 13.843 ciudadanos de los cuales 2174 son mayores de 75 anos (15.6% )Esto nos convierte en uno de los centro con poblacion mas envejecida de nuestra comunidad.Estamos ubicados en la Parte Vieja, contamos con muchos turistas y con la existencia de muchas barreras arquitectonicas .Todo ello dificulta el acceso a las personas con problemas de movilidad . Esto nos supone realizar un alto numero de domicilios ,tanto a enfermeras como a medicos, y nos hace plantearnos una nueva forma de organizarnos. Para ello ,lo primero en detectarse es una disparidad en la carga asistencial entre los diferentes cupos medicos, existiendo cupos con una alta presion asistencial a domicilio frente a otros con menor presencia en el domicilio;se plantea el formar parejas de cupos (cupo grande/cupo pequeno) permitiendo una distribucion mas homogenea del trabajo. Se disena una reestructuracion de las agendas para disponer de dias con mas tiempo para acudir a realizar visitas a domicilio. Este dia el otro cupo medico asume mayor actividad de consulta. En nuestro analisis se considera prioritario diferenciar los tiempos de la visita a domicilio en funcion de la complejidad.. se disenan avisos espontaneos de 20 minutos y avisos programados de 40 minutos . Ademas organizamos la atencion a domicilio urgente realizada por el equipo enfermera-medico que da respuesta a la demanda no demorable. Asi se evita interrumpir la agenda de los medicos que estan en consulta programada. Este sistema nos permite que pacientes que precisen un mayor seguimiento (pacientes pluripatologicos y pacientes en fase final de la vida) tengan un mayor soporte con dos EAP como referencia asistencial fomentando el trabajo compartido y multidisciplinar para la gestion de pacientes complejos.Es importante la labor que desarrolla el area de atencion al paciente en la gestion de las agendas de los profesionales implicados.Resulta clave la comunicacion con el paciente y se identifica como un problema la ausencia de informacion clinica actualizada en el domicilio del paciente, para solventar este problema se disena un documento escrito al que llamamos “carpeta del paciente”. Este documento es en soporte papel y debe ser periodicamente actualizado constando de dos areas bien diferencias. Una de ella dirigida al profesional y otra al paciente. De forma paralela se disena un pastillero al que llamamos “kit de rescate paciente cronico”. Este se disena de forma homogenea para todos los pacientes y pueden recurrir a el cuando se lo indican de forma telefonica el profesional sanitario responsable de su seguimiento .Esto le puede permitir al paciente modificar el tratamiento al paciente de forma inmediata evitando su desplazamiento a la oficina de farmacia. Con ello se pretende gestionar de forma mas adecuada nuestra actividad en los domicilio y mejorar la documentacion clinica en domicilio que permitiria una mejor toma de decisiones cuando el paciente no es atendido por su equipo habitual( emergencias, urgencia a domicilio...). Dispondriamos tambien de un botiquin de rescate .

Dimorphic plant species can show distinct nutrient needs due to sex-related differences in nutrient allocation to reproductive structures, which can potentially affect their sensitivity to photoinhibition and photo-oxidative stress. Here, we investigated sex-related differences in the extent of photo-oxidative stress in male and female individuals of U. dioica exposed to a combination of severe drought and nutrient starvation. Male and female individuals of U. dioica subject to severe drought stress were exposed to various levels of nutrient availability. First, a set of plants grown under field conditions and exposed to summer drought was used to test the effects of nutrient supply (given as NPK fertilizer). Secondly, the effects of various phosphate concentrations in the nutrient solution were tested in drought-stressed potted plants. The Fv/Fm ratio (maximum efficiency of PSII photochemistry), photoprotection capacity (levels of carotenoids, including the xanthophyll cycle, and vitamins C and E), and the extent of lipid peroxidation (hydroperoxide levels) were measured. Results showed that an application of the NPK fertilizer to the soil had a positive effect on drought-stressed plants, reducing the extent of lipid peroxidation in both males and females. P deficiency led to residual photoinhibition, as indicated by significant reductions in the Fv/Fm ratio, and enhanced lipid peroxidation in females, but not in males. We conclude that (i) increased nutrient availability in the soil can alleviate photo-oxidative stress in drought-stressed U. dioica plants, and (ii) U. dioica plants show sexual secondary dimorphism in terms of photoinhibition and photo-oxidative stress, but this is only apparent when stress infringed on plants is very severe.

Seed dormancy determines population dynamics and it is an essential feature of the ecology of high-mountain plants. Although altitudinal changes in the ecological and physiological performance of Pyrenean saxifrage (Saxifraga longifolia Lapeyr.) has been investigated to some extent, nothing it still know about how seed dormancy is influenced by environmental conditions imposed by altitude in these plants. Here, we evaluated altitudinal changes in seed viability and germination, but also on the endogenous contents of phytohormones and antioxidants in Pyrenean saxifrage. We found that, despite seed germination decreased at the highest population (2100 m a.s.l.) relative to the other two populations (at 570 and 1100 m a.s.l.), the highest population showed the highest seed viability, thus indicating increased seed dormancy. Hormonal profiling of the seeds revealed that this dormancy was modulated physiologically, in particular by increased abscisic acid accumulation, while gibberellin contents kept constant, relative to the seeds of the other two populations. Furthermore, seed xanthophyll contents, in particular those of lutein, neoxanthin, violaxanthin and antheraxanthin increased with altitude, while those of α-tocopherol kept unaltered. We conclude that the lower temperature imposed by altitude strongly influences not only seed viability and germination, but also seed dormancy, and that changes associated to temperature differences among populations are modulated at the physiological level by increasing the accumulation of abscisic acid and xantophylls in mature seeds. Results strongly support the contention that physiological seed dormancy has evolved as a means to increase plant survival under harsh environmental conditions in Pyrenean saxifrage plants growing in their natural habitat.

α-Actinin, an actin-binding protein of the spectrin superfamily, is present in most eukaryotes except plants. It is composed of three domains: N-terminal CH-domains, C-terminal calcium-binding domain (with EF-hand motifs), and a central rod domain. We have cloned and expressed Neurospora crassa α-actinin as GST and GFP fusion proteins for biochemical characterization and in vivo localization, respectively. The intracellular localization pattern of α-actinin suggests that this protein is intimately associated with actin filaments and plays an important role in the processes of germination, hyphal elongation, septum formation, and conidiation. These functions were confirmed by the experiments on the effect of α-actinin gene deletion in N. crassa.

El presente trabajo desarrolla la figura de la gestación por sustitución comenzando por su conceptualización, sus acepciones y características principales. Se coloca especial atención a los derechos humanos de las personas involucradas en este procedimiento, entre ellas, la gestante, los comitentes y el niño que nace.Las ventajas de obtener una regulación legal por sobre la prohibición expresa o el silencio de la ley, analizándose las distintas estrategias judiciales en Argentina. Finalmente, se explicitan las características de los proyectos de ley recientemente presentados en el ámbito legislativo argentino para impulsar una regulación integral de la gestación por sustitución.