Disruptive effects have been described on the plants and ecosystems of oceanic islands due to the introduction of invasive herbivores. In the Canary Islands the European rabbit (Oryctolagus cuniculus ...L.) was introduced five centuries ago and currently is widespread in all ecosystems, although in the laurel forests it is very scarce. However, on Morello-Ericetum woodland mostly represented by disturbed laurel forest areas, rabbit density is higher. Here we analyzed the impact of rabbits on the Morello-Ericetum woodland using exclusion and control plots located in 11 sites in the Garajonay National Park (La Gomera Island). Rabbit browsing was assessed for 36 endemic species, 15 of them threatened, which were sowed in both control and exclusion plots. After three years of monitoring, our results show a significant negative effect on the establishment and seedling recruitment for 55% of the analyzed species, especially in summer when the rabbit density increases by nearly 30%. Also, plant growth (in 91% of the species) and flowering rate (36% of the species), were disrupted, which could cause a depletion of the seed bank. Among the five tree species included in the experiment, three were also significantly damaged, so rabbits could be even influencing canopy species, delaying forest recovery. The management of Morello-Ericetum woodland should be countered the effects produced by the rabbits on their tree composition, and to allow the development of an understory where endemic species recover their abundance.
•Exclusion and control plots with sowing were used in this experiment.•Seedling recruitment, plant growth and flowering rate were disrupted.•At least 13 of 15 studied endangered species were browsed by the rabbits.•Seedling of some tree species was browsed, delaying the laurel forest recovery.
•Laurel forest recovery does not depend only on initial vegetation conditions.•The early recovery stage was driven by aspect and distance from young-growth forests.•In middle stage, the recovery was ...driven by old-growth forest cover around each site.•The oldest-growth forests showed more endemic, threatened species and β-diversity.
Deforestation and forest fragmentation have serious negative consequences for biodiversity and species distribution, but many studies approach species distributions and speciation processes without taking in account the local history of human disturbances. Nevertheless, the complex recovery process after forest destruction is widely distributed around the world and takes place under a wide mosaic of biotic and abiotic factors that may be influencing the species distribution. In this study aerial pictures from 1951 and 2019 were used to assess forest recovery during about sixty years. We tested if the initial stage (forest completely destroyed or young growth forest in 1951) determines the successional process, evaluating the role of different spatial drivers (distance from remnant forest fragments and unfelled areas around each site) and mesoclimate conditions, by examining 40 disturbed sites and 18 old-growth forest sites distinguished in 1951 aerial photos. The final stage during this successional process was assessed using 2019 aerial photos, covering the same these sites. At each plot, plant species composition and forest structure were studied, which allowed us to obtain a maturity index. Our results reveal that the initial stage is not the only driver explaining forest structure and species composition at the end of the 60-year period analyzed. The role of each forest recovery driver varies depending on each stage. In the early successional stages, the slope aspect (exposure) was the most important factor, which is correlated with mesoclimatic conditions, followed by the distance from young-growth forest in 1951. However, in intermediate successional stages the cover of old-growth forest around each plot in 1951 was the main factor in the recovery. At the end of the study period (2019), the differences in species richness between young-growth and old-growth forest were not significant, although old-growth forests were characterized by high densities of endemics, threatened species and β-diversity, showing the species composition a strong dependence on forest structure. Our results reveal the important need to consider human disturbance history in forest research and how climate conditions and the lack of nearby remnants can negatively affect the forest recovery process, greatly increasing the time needed to return to old-growth laurel forest conditions, which requires specific management recommendations.
The monitoring of ecosystems and forests is an urgent requirement in the current framework of global change. It is particularly necessary on oceanic islands where their rich biodiversity is highly ...vulnerable, with many narrow-ranged endemic species. Quantifying and mapping forest health through key ecological variables are essential steps for management, but it will also be challenging and may require a lot of resources. Remote sensing has the potential to be a very useful tool to assess the development and conservation status of forests. We assessed the applicability of the light detection and ranging (LiDAR) on the laurel forests of La Gomera, making allometric equations for various measurements of the forest structure, linking field inventory from 2019 and 2017 LiDAR data through standard linear regressions. Decision trees and logistic regressions were also used to assess the performance of LiDAR in the recognition of young-growth and old-growth laurel forests. The obtained allometric models were a good fit in general and their predictions were in line with already known data. Likewise, decision tree and logistic regression to distinguish young-growth and old-growth forests had a similar performance in both cases, with a high to medium-high degree of accuracy. Therefore, LiDAR was revealed to be a useful tool for the monitoring of the laurel forest by the managers.
Climate change is modifying plant communities and ecosystems around the world. Alpine ecosystems are of special concern on oceanic islands, due to their characteristic higher endemicity percentage, ...small area and undergoing severe climate change impact in the last few decades. During recent decades there has been increasing interest in the effects of climate change on biodiversity and a range of methods have been developed to assess species vulnerability. However, some new insights are necessary to obtain useful information for species management on oceanic islands. Here in the alpine area of two oceanic islands (Tenerife and La Palma) we evaluate the drivers that best explain the vulnerability of 63 endemic species along three scenarios, covering recent past to present and two future projections (2041–2060 and 2061–2080). The selected drivers were: loss of potential area, mismatch index between potential and occupied areas in different scenarios, and adaptive capacity constraints. We assess the influence of potential area size and whether the drivers of risk and the vulnerability for common, restricted and rare species are significantly different. Our results indicate that management must be widely distributed over the species, and not only focus on restricted species. Evidence for this was that drivers directly deriving from climate change showed no significant differences in their impact on the rarity groups identified. Vulnerability depends partially on the potential area size, showing a more complex picture where constraints on the adaptive capacity of the species have a strong enough influence to modify the effects of the characteristic drivers of climate change.
► Fibroproliferative diseases are prominent causes of morbidity and mortality worldwide and may lead to metastatic cancer. ► Pirfenidone has been proposed as an alternative treatment in various ...pathologies that develop fibrosis. ► The erythrocyte micronucleus assay is a simple and highly informative method that detects in vivo chromosome aberrations. ► No evidence of genotoxic or cytotoxic effects of pirfenidone were observed in two adult rodent models. ► No genotoxic effects or cytotoxicity were observed in newborn rats transplacentally exposed to pirfenidone.
Pirfenidone is a non-steroidal antifibrotic compound that has been proposed in clinical protocols and experimental studies as a pharmacological treatment for fibroproliferative diseases. The objective of this study was to determine the genotoxicity or cytotoxicity of three doses of pirfenidone using the micronuclei test in peripheral blood erythrocytes of rodent models. Pirfenidone was administered orally to Balb-C mice for 3days, and also was administered topically to hairless Sprague Dawley rats during the final stage of gestation. Mice were sampled every 24h over the course of 6days; pregnant rats were sampled every 24h during the last 6days of gestation, and pups were sampled at birth. Blood smears were analyzed and the frequencies of micronucleated erythrocytes (MNEs), micronucleated polychromatic erythrocytes (MNPCEs), and the proportion of polychromatic erythrocytes (PCEs), were recorded in samples from mice, pregnant rats and rat neonates. Increases in MN frequencies (p<0.03) were noted only in the positive control groups. No genotoxic effects or decreased PCE values were observed neither in newborn rats transplacentally exposed to pirfenidone, or in two adult rodent models when pirfenidone was administered orally or topically.
Among patients with acute coronary syndrome following transcatheter aortic valve replacement (TAVR), those presenting with ST-segment elevation myocardial infarction (STEMI) are at highest risk.
The ...goal of this study was to determine the clinical characteristics, management, and outcomes of STEMI after TAVR.
This was a multicenter study including 118 patients presenting with STEMI at a median of 255 days (interquartile range: 9 to 680 days) after TAVR. Procedural features of STEMI after TAVR managed with primary percutaneous coronary intervention (PCI) were compared with all-comer STEMI: 439 non-TAVR patients who had primary PCI within the 2 weeks before and after each post-TAVR STEMI case in 5 participating centers from different countries.
Median door-to-balloon time was higher in TAVR patients (40 min interquartile range: 25 to 57 min vs. 30 min interquartile range: 25 to 35 min; p = 0.003). Procedural time, fluoroscopy time, dose-area product, and contrast volume were also higher in TAVR patients (p < 0.01 for all). PCI failure occurred more frequently in patients with previous TAVR (16.5% vs. 3.9%; p < 0.001), including 5 patients in whom the culprit lesion was not revascularized owing to coronary ostia cannulation failure. In-hospital and late (median of 7 months interquartile range: 1 to 21 months) mortality rates were 25.4% and 42.4%, respectively (20.6% and 38.2% in primary PCI patients), and estimated glomerular filtration rate <60 ml/min (hazard ratio HR: 3.02; 95% confidence interval CI: 1.42 to 6.43; p = 0.004), Killip class ≥2 (HR: 2.74; 95% CI: 1.37 to 5.49; p = 0.004), and PCI failure (HR: 3.23; 95% CI: 1.42 to 7.31; p = 0.005) determined an increased risk.
STEMI after TAVR was associated with very high in-hospital and mid-term mortality. Longer door-to-balloon times and a higher PCI failure rate were observed in TAVR patients, partially due to coronary access issues specific to the TAVR population, and this was associated with poorer outcomes.
The thyroid nodule is a frequent cause of primary care consultation. The prevalence of a palpable thyroid nodule is approximately 4-7%, increasing up to 67% by the incidental detection of nodules on ...ultrasound. The vast majority are benign and asymptomatic, staying stable over time. The clinical importance of studying a thyroid nodule is to exclude thyroid cancer, which occurs in 5 to 10% of the nodules. The Board of SOCHED (Chilean Society of Endocrinology and Diabetes) asked the Thyroid Study Group to develop a consensus regarding the diagnostic management of the thyroid nodule in Chile, aimed at non-specialist physicians and adapted to the national reality. To this end, a multidisciplinary group of 31 experts was established among university academics, active researchers with publications on the subject and prominent members of scientific societies of endocrinology, head and neck surgery, pathology and radiology. A total of 14 questions were developed with key aspects for the diagnosis and subsequent referral of patients with thyroid nodules, which were addressed by the participants. In those areas where the evidence was insufficient or the national reality had to be considered, the consensus opinion of the experts was used through the Delphi methodology. The consensus was approved by the SOCHED board for publication.
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