El Hierro Island Volcanological Science: An Overview

El Hierro Island, the youngest of the Canary Islands, and its latest eruption in 2011–2012 have been a playground of fruitful decade-long studies. In this book, we summarize and provide future venues of action to solve outstanding questions. The topics cover geological studies of Holocene volcanism so it informs past, present and future activity. Its active magmatic system from a petrological and geophysical lens. How monitoring of volcanic activity can be optimized and how to read the data streams in a meaningful way. The marine environmental effects of a submarine eruption are covered in detail, as well as how the society could be properly engage to reduce the risks associated to it, and appreciate and benefit from it. So, in each chapter the reader should find inspiration and future challenges waiting to be solved. Remaining puzzles pieces about how volcanism works and how it affects its environment. An effort to provide food for thoughts of future Canary Islands volcanological research, and in particular El Hierro.

González, Pablo J.

El Hierro Island. Active Volcanoes of the World (1): 1-16 (2023)
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Spatial resolution impacts projected plant responses to climate change on topographically complex islands

Aim: Understanding how grain size affects our ability to characterize species responses to ongoing climate change is of crucial importance in the context of an increasing awareness for the substantial difference that exists between coarse spatial resolution macroclimatic data sets and the microclimate actually experienced by organisms. Climate change impacts on biodiversity are expected to peak in mountain areas, wherein the differences between macro and microclimates are precisely the largest. Based on a newly generated fine-scale environmental data for the Canary Islands, we assessed whether data at 100 m resolution is able to provide more accurate predictions than available data at 1 km resolution. We also analysed how future climate suitability predictions of island endemic bryophytes differ depending on the grain size of grids.

Location: Canary Islands.

Time period: Present (1979–2013) and late-century (2071–2100).

Taxa: Bryophytes.

Methods: We compared the accuracy and spatial predictions using ensemble of small models for 14 Macaronesian endemic bryophyte species. We used two climate data sets: CHELSA v1.2 (~1 km) and CanaryClim v1.0 (100 m), a downscaled version of the latter utilizing data from local weather stations. CanaryClim also encompasses future climate data from five individual model intercomparison projects for three warming shared socio-economic pathways.

Results: Species distribution models generated from CHELSA and CanaryClim exhibited a similar accuracy, but CanaryClim predicted buffered warming trends in mid-elevation ridges. CanaryClim consistently returned higher proportions of newly suitable pixels (8%–28%) than CHELSA models (0%–3%. Consequently, the proportion of species predicted to occupy pixels of uncertain suitability was higher with CHELSA (3–8 species) than with CanaryClim (0–2 species.

Main conclusions: The resolution of climate data impacted the predictions rather than the performance of species distribution models. Our results highlight the crucial role that fine-resolution climate data sets can play in predicting the potential distribution of both microrefugia and new suitable range under warming climate.

Patiño, Jairo; Collart, Flavien; Vanderpoorten, Alain; Martin-Esquivel, José Luis; Naranjo-Cigala, Agustín; Mirolo, Sébastien; Karger, Dirk N.

Diversity and Distributions, 29(10): 1245-1262 (2023)
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Lewis Acid-Catalyzed Carbonyl-Ene Reaction: Interplay between Aromaticity, Synchronicity, and Pauli Repulsion

The physical factors governing the catalysis in Lewis acid-promoted carbonyl-ene reactions have been explored in detail quantum chemically. It is found that the binding of a Lewis acid to the carbonyl group directly involved in the transformation greatly accelerates the reaction by decreasing the corresponding activation barrier up to 25 kcal/mol. The Lewis acid makes the process much more asynchronous and the corresponding transition state less in-plane aromatic. The remarkable acceleration induced by the catalyst is ascribed, by means of the activation strain model and the energy decomposition analysis methods, mainly to a significant reduction of the Pauli repulsion between the key occupied π-molecular orbitals of the reactants and not to the widely accepted stabilization of the LUMO of the enophile.

Rodríguez, Humberto A.; Cruz, Daniel A.; Padrón, Juan I.; Fernández, Israel.

The Journal of Organic Chemistry 88, 15: 11102–11110 (2023)
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Indirect effects shape species fitness in coevolved mutualistic networks

Ecological interactions are one of the main forces that sustain Earth’s biodiversity. A major challenge for studies of ecology and evolution is to determine how these interactions affect the fitness of species when we expand from studying isolated, pairwise interactions to include networks of interacting species1,2,3,4. In networks, chains of effects caused by a range of species have an indirect effect on other species they do not interact with directly, potentially affecting the fitness outcomes of a variety of ecological interactions (such as mutualism)5,6,7. Here we apply analytical techniques and numerical simulations to 186 empirical mutualistic networks and show how both direct and indirect effects alter the fitness of species coevolving in these networks. Although the fitness of species usually increased with the number of mutualistic partners, most of the fitness variation across species was driven by indirect effects. We found that these indirect effects prevent coevolving species from adapting to their mutualistic partners and to other sources of selection pressure in the environment, thereby decreasing their fitness. Such decreases are distributed in a predictable way within networks: peripheral species receive more indirect effects and experience higher reductions in fitness than central species. This topological effect was also evident when we analysed an empirical study of an invasion of pollination networks by honeybees. As honeybees became integrated as a central species within networks, they increased the contribution of indirect effects on several other species, reducing their fitness. Our study shows how and why indirect effects can govern the adaptive landscape of species-rich mutualistic assemblages.

Cosmo, Leandro G.; Assis, Ana Paula A.; de Aguiar, Marcus A. M.; Pires, Mathias M.; Valido, Alfredo; Jordano, Pedro; Thompson, John N.; Bascompte, Jordi; Guimarães Jr., Paulo R.

Nature, 619: 1-18 (2023)
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Marine Meroterpenoids Isolated from Gongolaria abies-marina Induce Programmed Cell Death in Naegleria fowleri

Naegleria fowleri is the causative agent of a central nervous system affecting disease called primary amoebic meningoencephalitis. It is a fulminant disease with a rapid progression that affects mainly children and young adults who report previous water exposure. Current treatment options are not totally effective and involve several side effects. In this work, six meroterpenoids isolated from the brown algae Gongolaria abies-marina were evaluated against N. fowleri. Gongolarone B (1), 6Z-1′-methoxyamentadione (2), and 1′-methoxyamentadione (3) were the most active molecules against N. fowleri with IC50 values between 13.27 ± 0.96 µM and 21.92 ± 1.60 µM. However, cystomexicone B (6) was the molecule with the highest selectivity index (>8.5). Moreover, all these compounds induced different cellular events compatible with the apoptosis-like PCD process, such as chromatin condensation, damages at the mitochondrial level, cell membrane disruption, and production of reactive oxygen species (ROS). Therefore, G. abies-marina could be considered as a promising source of active molecules to treat the N. fowleri infections.

Arberas-Jiménez, Íñigo; Rodríguez-Expósito, Rubén L.; San Nicolás-Hernández, Desirée; Chao-Pellicer, Javier; Sifaoui, Inés; Díaz-Marrero, Ana R.; Fernández, José J.; Piñero, José E.; Lorenzo-Morales, Jacob.

Pharmaceuticals 16(7), 1010: 1-14 (2023)
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Synthesis of Structurally Related Coumarin Derivatives as Antiproliferative Agents

A library of structurally related coumarins was generated through synthesis reactions and chemical modification reactions to obtain derivatives with antiproliferative activity both in vivo and in vitro. Out of a total of 35 structurally related coumarin derivatives, seven of them showed inhibitory activity in in vitro tests against Taq DNA polymerase with IC50 values lower than 250 μM. The derivatives 4-(chloromethyl)-5,7-dihydroxy-2H-chromen-2-one (2d) and 4-((acetylthio)methyl)-2-oxo-2H-chromen-7-yl acetate (3c) showed the most promising anti-polymerase activity with IC50 values of 20.7 ± 2.10 and 48.25 ± 1.20 μM, respectively. Assays with tumor cell lines (HEK 293 and HCT-116) were carried out, and the derivative 4-(chloromethyl)-7,8-dihydroxy-2H-chromen-2-one (2c) was the most promising, with an IC50 value of 8.47 μM and a selectivity index of 1.87. In addition, the derivatives were evaluated against Saccharomyces cerevisiae strains that report about common modes of actions, including DNA damage, that are expected for agents that cause replicative stress. The coumarin derivatives 7-(2-(oxiran-2-yl)ethoxy)-2H-chromen-2-one (5b) and 7-(3-(oxiran-2-yl)propoxy)-2H-chromen-2-one (5c) caused DNA damage in S. cerevisiae. The O-alkenylepoxy group stands out as that with the most important functionality within this family of 35 derivatives, presenting a very good profile as an antiproliferative scaffold. Finally, the in vitro antiretroviral capacity was tested through RT-PCR assays. Derivative 5c showed inhibitory activity below 150 μM with an IC50 value of 134.22 ± 2.37 μM, highlighting the O-butylepoxy group as the functionalization responsible for the activity.

Bruna-Haupt, Ezequiel F.; Perretti, Marcelle D.; Garro, Hugo A.; Carrillo Fumero, Romen; Machín, Félix; Lorenzo-Castrillejo, Isabel; Gutiérrez, Lucas; Vega-Hissi, Esteban G.; Mamberto, Macarena; Menacho-Marquez, Mauricio; Fernández, Claudio O.; García, Celina; Pungitore, Carlos R.

ACS Omega, 8(29): 26479 - 26496 (2023)
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From reactive species to disease development: Effect of oxidants and antioxidants on the cellular biomarkers

The influence of modern lifestyle, diet, exposure to chemicals such as phytosanitary substances, together with sedentary lifestyles and lack of exercise play an important role in inducing reactive stress (RS) and disease. The imbalance in the production and scavenging of free radicals and the induction of RS (oxidative, nitrosative, and halogenative) plays an essential role in the etiology of various chronic pathologies, such as cardiovascular diseases, diabetes, neurodegenerative diseases, and cancer. The implication of free radicals and reactive species injury in metabolic disturbances and the onset of many diseases have been accumulating for several decades, and are now accepted as a major cause of many chronic diseases. Exposure to elevated levels of free radicals can cause molecular structural impact on proteins, lipids, and DNA, as well as functional alteration of enzyme homeostasis, leading to aberrations in gene expression. Endogenous depletion of antioxidant enzymes can be mitigated using exogenous antioxidants. The current interest in the use of exogenous antioxidants as adjunctive agents for the treatment of human diseases allows a better understanding of these diseases, facilitating the development of new therapeutic agents with antioxidant activity to improve the treatment of various diseases. Here we examine the role that RS play in the initiation of disease and in the reactivity of free radicals and RS in organic and inorganic cellular components.

Curieses Andrés, Celia María; Pérez de Lastra, José Manuel; Andrés Juan, Celia; Plou Gasca, Francisco José; Pérez-Lebeña, Eduardo.

Journal of Biochemical and Molecular Toxicology, 37(11): 1-17 (2023)
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Conversion of Hydroxyproline “Doubly Customizable Units” to Hexahydropyrimidines: Access to Conformationally Constrained Peptides

The efficient transformation of hydroxyproline “doubly customizable units” into rigid hexahydropyrimidine units takes place in good global yields and generates compounds of pharmaceutical interest. In particular, the process can readily provide access to peptidomimetics and peptides with reversed sequences or with valuable turns.

Hernández, Dácil; Porras, Marina; Boto, Alicia.

The Journal of Organic Chemistry, 88, 14: 9910-9919 (2023)
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Volcanic ash deposition as a selection mechanism towards woodiness

The high proportion of woody plant species on oceanic islands has hitherto been explained mainly by gradual adaptation to climatic conditions. Here, we present a novel hypothesis that such woodiness is adaptative to volcanic ash (tephra) deposition. Oceanic islands are subject to frequent eruptions with substantial and widespread ash deposition on evolutionary time scales. We postulate that this selects for woodiness through an increased ability to avoid burial of plant organs by ash, and to re-emerge above the new land surface. We sense-checked using observations of plant occurrences and distributions on La Palma (Canary Islands) in April 2022, 4 months after the end of the eruptions of the Tajogaite volcano (Cumbre Vieja ridge). In contrast to herbs and grasses, most woody plants persisted and were already in full flower in areas with 10+ cm ash deposition. Remarkably, these persisting woody plants were almost exclusively endemics.

Beierkuhnlein, Carl; Nogales, Manuel; Field, Richard; Vetaas, Ole R.; Walentowitz, Anna; Weiser, Frank; Stahlmann, Reinhold; Guerrero-Campos, María; Jentsch, Anke; Medina, Félix M.; Chiarucci, Alessandro.

Npj Biodiversity., 2, 14: 1-8 (2023)
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Análisis de la relación entre la contaminación del aire ambiente y la gravedad de las descompensaciones por insuficiencia cardiaca en dos metrópolis españolas (Barcelona y Madrid)

Objetivos: Analizar si la exposición a contaminantes del aire en 2 grandes ciudades españolas está relacionada con la gravedad de las descompensaciones de la insuficiencia cardiaca (IC).

Método: Se estudiaron pacientes con IC descompensada en urgencias de 4 hospitales de Barcelona y 3 de Madrid. Se recogieron datos clínicos (edad, sexo, comorbilidades, situación funcional basal), atmosféricos (temperatura, presión atmosférica) y de contaminantes (SO2, NO2, CO, O3, PM10, PM2,5) el día de atención en urgencias. La gravedad de la descompensación se estimó mediante la mortalidad a 7 días (indicador primario) y la necesidad de hospitalización, mortalidad intrahospitalaria y hospitalización prolongada (indicadores secundarios). Se investigó la asociación ajustada por datos clínicos, atmosféricos y ciudad entre concentración de contaminantes y gravedad, mediante regresión logística (asunción de linealidad) y curvas spline cúbicas restringidas (no asunción de linealidad).

Resultados: Se incluyeron 5.292 descompensaciones, con edad mediana de 83 años (RIC = 76-88) y 56% mujeres. Las medianas (RIC) de los promedios diarios de contaminantes fueron: SO2 = 2,5 μg/m3 (1,4-7,0), NO2 = 43 μg/m3 (34-57), CO = 0,48 mg/m3 (0,35-0,63), O3 = 35 μg/m3 (25-48), PM10 = 22 μg/m3 (15-31) y PM2,5 = 12 μg/m3 (8-17). La mortalidad a 7 días fue del 3,9%, y la hospitalización, la mortalidad intrahospitalaria y la hospitalización prolongada, del 78,9, 6,9 y 47,5%, respectivamente. El SO2 fue el único contaminante que mostró asociación lineal con la gravedad de la descompensación, ya que cada unidad de incremento supuso una OR para necesidad de hospitalización de 1,04 (IC 95% 1,01-1,08). El estudio mediante curvas spline cúbicas restringidas tampoco mostró asociaciones nítidas entre contaminantes y gravedad, excepto para SO2 y hospitalización, con OR de 1,55 (IC 95% 1,01-2,36) y de 2,71 (IC 95% 1,13-6,49) para concentraciones de 15 y 24 μg/m3, respectivamente, en relación con una concentración de referencia de 5 μg/m3.

Conclusión: La exposición a contaminantes del aire ambiente, en un rango de concentraciones medio a bajo, en general no está relacionado con la gravedad de las descompensaciones de la IC, y solo el SO2 podría estar asociado a una mayor necesidad de hospitalización.

Benito-Lozano, Miguel; López-Ayala, Pedro; Rodríguez, Sergio; Llorens, Pere; Domínguez-Rodríguez, Alberto; Aguirre, Alfons; Alquézar, Aitor; Jacob, Javier; Gil, Víctor; Martín-Sánchez, Francisco Javier; Mir, María; Andueza, Juan Antonio; Burillo-Putze, Guillermo; Miró, Òscar.

Medicina Clínica, 161(1): 11-19 (2023)
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