Exploring the response of a key Mediterranean gorgonian to heat stress across biological and spatial scales.

Understanding the factors and processes that shape intra-specific sensitivity to heat stress is fundamental to better predicting the vulnerability of benthic species to climate change. Here, we investigate the response of a habitat-forming Mediterranean octocoral, the red gorgonian Paramuricea clavata (Risso, 1826) to thermal stress at multiple biological and geographical scales. Samples from eleven P. clavata populations inhabiting four localities separated by hundreds to more than 1500 km of coast and with contrasting thermal histories were exposed to a critical temperature threshold (25 °C) in a common garden experiment in aquaria. Ten of the 11 populations lacked thermotolerance to the experimental conditions provided (25 days at 25 °C), with 100% or almost 100% colony mortality by the end of the experiment. Furthermore, we found no significant association between local average thermal regimes nor recent thermal history (i.e., local water temperatures in the 3 months prior to the experiment) and population thermotolerance. Overall, our results suggest that local adaptation and/or acclimation to warmer conditions have a limited role in the response of P. clavata to thermal stress. The study also confirms the sensitivity of this species to warm temperatures across its distributional range and questions its adaptive capacity under ocean warming conditions. However, important inter-individual variation in thermotolerance was found within populations, particularly those exposed to the most severe prior marine heatwaves. These observations suggest that P. clavata could harbor adaptive potential to future warming acting on standing genetic variation (i.e., divergent selection) and/or environmentally-induced phenotypic variation (i.e., intra- and/or intergenerational plasticity).

Loss of a globally unique kelp forest from Oman.

Kelp forests are declining in many regions globally with climatic perturbations causing shifts to alternate communities and significant ecological and economic loss. Range edge populations are often at most risk and are often only sustained through localised areas of upwelling or on deeper reefs. Here we document the loss of kelp forests (Ecklonia radiata) from the Sultanate of Oman, the only confirmed northern hemisphere population of this species. Contemporary surveys failed to find any kelp in its only known historical northern hemisphere location, Sadah on the Dhofar coast. Genetic analyses of historical herbarium specimens from Oman confirmed the species to be E. radiata and revealed the lost population contained a common CO1 haplotype found across South Africa, Australia and New Zealand suggesting it once established through rapid colonisation throughout its range. However, the Omani population also contained a haplotype that is found nowhere else in the extant southern hemisphere distribution of E. radiata. The loss of the Oman population could be due to significant increases in the Arabian Sea temperature over the past 40 years punctuated by suppression of coastal upwelling. Climate-mediated warming is threatening the persistence of temperate species and precipitating loss of unique genetic diversity at lower latitudes.

Global warming assessment suggests the endemic Brazilian kelp beds to be an endangered ecosystem.

Kelps are canopy-forming brown seaweed sustaining critical ecosystem services in coastal habitats, including shelter, nursery grounds, and providing food resources to a myriad of associated species. This study modeled the fundamental niche of Laminaria abyssalis along the Brazilian continental margin, an endemic species of the South Atlantic, to anticipate potential distributional range shifts under two contrasting scenarios of future environmental changes (RCP2.6 and RCP8.5). The model for fundamental niche predictions considering the "present scenario" has shown a wider potential area than the realized niche (i.e., the area where the species actually occurs) along the Brazilian coast. In both future scenarios, the models have shown niche erosion on the northern portion of the Brazilian coast and niche gains towards the south. In both scenarios, L. abyssalis populations tend to shift to deeper regions of the reef. The restricted range of occurrence (33,000 km2), intense anthropic activities along these beds (e.g., trawling fisheries, oil/gas mining, or removal for agricultural purposes) acting synergically with global warming, may drive this ecosystem to collapse faster than kelp species' ability to adapt. We propose to classify L. abyssalis as Endangered - (EN) under IUCN criteria, and highlight that long-term monitoring of kelp beds is an urgent need to develop effective conservation initiatives to protect such rare and invaluable ecosystem.

Weak biodiversity connectivity in the European network of no-take marine protected areas.

The need for international cooperation in marine resource management and conservation has been reflected in the increasing number of agreements aiming for effective and well-connected networks of Marine Protected Areas (MPAs). However, the extent to which individual MPAs are connected remains mostly unknown. Here, we use a biophysical model tuned with empirical data on species dispersal ecology to predict connectivity of a vast spectrum of biodiversity in the European network of marine reserves (i.e., no-take MPAs). Our results highlight the correlation between empirical propagule duration data and connectivity potential and show weak network connectivity and strong isolation for major ecological groups, resulting from the lack of direct connectivity corridors between reserves over vast regions. The particularly high isolation predicted for ecosystem structuring species (e.g., corals, sponges, macroalgae and seagrass) might potentially undermine biodiversity conservation efforts if local retention is insufficient and unmanaged populations are at risk. Isolation might also be problematic for populations' persistence in the light of climate change and expected species range shifts. Our findings provide novel insights for management directives, highlighting the location of regions requiring additional marine reserves to function as stepping-stone connectivity corridors.

Analysis of 13 C and 14 C labeling in pyruvate and lactate in tumor and blood of lymphoma-bearing mice injected with 13 C- and 14 C-labeled pyruvate.

Measurements of hyperpolarized 13 C label exchange between injected [1-13 C]pyruvate and the endogenous tumor lactate pool can give an apparent first-order rate constant for the exchange. The determination of the isotope flux, however, requires an estimate of the labeled pyruvate concentration in the tumor. This was achieved here by measurement of the tumor uptake of [1-14 C]pyruvate, which showed that <2% of the injected pyruvate reached the tumor site. Multiplication of this estimated labeled pyruvate concentration in the tumor with the apparent first-order rate constant for hyperpolarized 13 C label exchange gave an isotope flux that showed good agreement with a flux determined directly by the injection of non-polarized [3-13 C]pyruvate, rapid excision of the tumor after 30 s and measurement of 13 C-labeled lactate concentrations in tumor extracts. The distribution of labeled lactate between intra- and extracellular compartments and the blood pool was investigated by imaging, by measurement of the labeled lactate concentration in blood and tumor, and by examination of the effects of a gadolinium contrast agent and a lactate transport inhibitor on the intensity of the hyperpolarized [1-13 C]lactate signal. These measurements showed that there was significant export of labeled lactate from the tumor, but that labeled lactate in the blood pool produced by the injection of hyperpolarized [1-13 C]pyruvate showed only relatively low levels of polarization. This study shows that measurements of hyperpolarized 13 C label exchange between pyruvate and lactate in a murine tumor model can provide an estimate of the true isotope flux if the concentration of labeled pyruvate that reaches the tumor can be determined.

Larval development and allometric growth of the black-faced blenny Tripterygion delaisi.

Larval development and allometric growth patterns of the black-faced blenny Tripterygion delaisi are described from a larval series (body length, LB = 3·30-12·10 mm) caught by light traps at the Arrábida Marine Park, Portugal. Larvae of T. delaisi possess distinctive morphometric and meristic characteristics which can be used to identify this species from related taxa. Pigmentation is sparse but characteristic, consisting of pigmented eyes, gas bladder pigmentation in the dorsal region, anal pigmentation and a row of regularly spaced postanal ventral melanophores. This pattern is present from as early as the yolk-sac stage and persists throughout all stages with just the addition of head and caudal pigmentation during the flexion and postflexion stages, respectively. The majority of fin development (with the exception of the caudal fin), occurs in the later stages of development. Myomere counts range between 37 and 45 for all stages. Growth is allometric during larval development. When inflexion points of growth were detected, growth was found to be biphasic with the inflexion points occurring within a very narrow range of LB (8·70-8·90 mm) close to the mean ± s.d. (9·44 ± 1·48 mm LB ) of postflexion larvae. Considering allometric growth patterns and ontogenetic descriptions together, the first developmental phase includes the preflexion and flexion stage larvae, while the second phase characterises the postflexion larvae prior to the transition from larvae to juvenile.

Major shifts at the range edge of marine forests: the combined effects of climate changes and limited dispersal.

Global climate change is likely to constrain low latitude range edges across many taxa and habitats. Such is the case for NE Atlantic marine macroalgal forests, important ecosystems whose main structuring species is the annual kelp Saccorhiza polyschides. We coupled ecological niche modelling with simulations of potential dispersal and delayed development stages to infer the major forces shaping range edges and to predict their dynamics. Models indicated that the southern limit is set by high winter temperatures above the physiological tolerance of overwintering microscopic stages and reduced upwelling during recruitment. The best range predictions were achieved assuming low spatial dispersal (5 km) and delayed stages up to two years (temporal dispersal). Reconstructing distributions through time indicated losses of ~30% from 1986 to 2014, restricting S. polyschides to upwelling regions at the southern edge. Future predictions further restrict populations to a unique refugium in northwestern Iberia. Losses were dependent on the emissions scenario, with the most drastic one shifting ~38% of the current distribution by 2100. Such distributional changes might not be rescued by dispersal in space or time (as shown for the recent past) and are expected to drive major biodiversity loss and changes in ecosystem functioning.

Entangled fates of holobiont genomes during invasion: nested bacterial and host diversities in Caulerpa taxifolia.

Successful prevention and mitigation of biological invasions requires retracing the initial steps of introduction, as well as understanding key elements enhancing the adaptability of invasive species. We studied the genetic diversity of the green alga Caulerpa taxifolia and its associated bacterial communities in several areas around the world. The striking congruence of α and ß diversity of the algal genome and endophytic communities reveals a tight association, supporting the holobiont concept as best describing the unit of spreading and invasion. Both genomic compartments support the hypotheses of a unique accidental introduction in the Mediterranean and of multiple invasion events in southern Australia. In addition to helping with tracing the origin of invasion, bacterial communities exhibit metabolic functions that can potentially enhance adaptability and competitiveness of the consortium they form with their host. We thus hypothesize that low genetic diversities of both host and symbiont communities may contribute to the recent regression in the Mediterranean, in contrast with the persistence of highly diverse assemblages in southern Australia. This study supports the importance of scaling up from the host to the holobiont for a comprehensive understanding of invasions.

Do hatchery-reared sea urchins pose a threat to genetic diversity in wild populations?

In salmonids, the release of hatchery-reared fish has been shown to cause irreversible genetic impacts on wild populations. However, although responsible practices for producing and releasing genetically diverse, hatchery-reared juveniles have been published widely, they are rarely implemented. Here, we investigated genetic differences between wild and early-generation hatchery-reared populations of the purple sea urchin Paracentrotus lividus (a commercially important species in Europe) to assess whether hatcheries were able to maintain natural levels of genetic diversity. To test the hypothesis that hatchery rearing would cause bottleneck effects (that is, a substantial reduction in genetic diversity and differentiation from wild populations), we compared the levels and patterns of genetic variation between two hatcheries and four nearby wild populations, using samples from both Spain and Ireland. We found that hatchery-reared populations were less diverse and had diverged significantly from the wild populations, with a very small effective population size and a high degree of relatedness between individuals. These results raise a number of concerns about the genetic impacts of their release into wild populations, particularly when such a degree of differentiation can occur in a single generation of hatchery rearing. Consequently, we suggest that caution should be taken when using hatchery-reared individuals to augment fisheries, even for marine species with high dispersal capacity, and we provide some recommendations to improve hatchery rearing and release practices. Our results further highlight the need to consider the genetic risks of releasing hatchery-reared juveniles into the wild during the establishment of restocking, stock enhancement and sea ranching programs.

Limited differences in fish and benthic communities and possible cascading effects inside and outside a protected marine area in Sagres (SW Portugal).

Marine protected areas (MPAs) are a relatively recent fisheries management and conservation tool for conservation of marine ecosystems and serve as experimental grounds to assess trophic cascade effects in areas were fishing is restricted to some extent. A series of descriptive field studies were performed to assess fish and benthic communities between two areas within a newly established MPA in SW Portugal. We characterized benthic macroalgal composition and determined the size, density and biomass of the main benthic predatory and herbivorous fish species as well as the main benthic herbivorous invertebrates to assess indications of top-down control on the phytobenthic assemblages. Fish species were identical inside and outside the MPA, in both cases Sarpa salpa was the most abundant fish herbivore and Diplodus spp. accounted for the great majority of the benthic predators. However, size and biomass of D. spp. were higher inside than outside the MPA. The main herbivorous invertebrate was the sea urchin Paracentrotus lividus, which was smaller and predominantly showing a crevice-dwelling behaviour in the MPA. In addition, P. lividus size frequency distribution showed a unimodal pattern outside and a bimodal pattern inside the MPA. We found significant differences in the algal assemblages between inside and outside the MPA, with higher abundance of turf and foliose algae inside, and articulated calcareous and corticated macrophytes outside the MPA, but no differences in the invasive Asparagopsis spp. The obtained results show differences in predatory fish and benthic community structure, but not in species richness, inside and outside the MPA. We hypothesize these differences lead to variation in species interactions: directly through predation and indirectly via affecting sea urchins behavioural patterns, predators might drive changes in macroalgal assemblages via trophic cascade in the study area. However due to non-biological differences between the two areas it is difficult to suggest that the MPA causes increased biological parameters of targeted species and to assess predatory control and trophic cascade effects in areas where fishing pressure is reduced. It is therefor advisable to design MPAs so that their impacts can be scientifically evaluated in a proper fashion.

A transcriptome resource for the copepod Calanus glacialis across a range of culture temperatures.

The copepod Calanus glacialis plays a key role in the Arctic pelagic ecosystem. Despite its ecological importance and ongoing climate changes, limited knowledge at the genomic level has hindered the understanding of the molecular processes underlying environmental stress responses and ecological adaptation. Transcriptome data was generated from an experiment with C. glacialis copepodite (CV) subjected to five different temperatures. We obtained a total of 512,352 high-quality 454 pyrosequencing reads, which were assembled into 55,562 contigs distributed in 128 KEGG pathways. Functional analysis revealed numerous genes related to diverse biological functions and processes, including members of all major conserved signaling pathways. Comparative analysis of acclimated individuals to experimental temperatures has provided information about gene variations observed in several pathways (e.g. genes involved in energy, lipid and amino acid metabolism were shown to be down-regulated with increasing temperatures). These mRNA sequence resources will facilitate further studies on genomics and physiology-driven molecular processes in C. glacialis and related species.

Case report of an endovascular repair of a residual type A dissection using a not CE not FDA-approved Najuta thoracic stent graft system.

This report describes an endovascular repair of a residual type A dissection using a medical device that is not marked by european conformity (CE) or Food and Drug Administration (FDA).The patient underwent ascending aortic surgery for acute type A dissection. The 2-year angio-computed tomography demonstrated patency of the residual false lumen with evolution into a 6 cm aneurysm, the extension of the dissection from the aortic arch to the aortic bifurcation with thrombosis of the right common iliac artery. There was no CE- or FDA-marked medical device indicated for this case or any other acceptable therapeutic alternative.We used the Najuta thoracic stent graft and successfully handled the pathology in a multiple-phase treatment.Technology is evolving with specific grafts for the ascending and fenestrated grafts for the aortic arch. In this single case the Najuta endograft, in spite of the periprocedural problems, was a valid therapeutic option.

Climate-driven range shifts explain the distribution of extant gene pools and predict future loss of unique lineages in a marine brown alga.

The climate-driven dynamics of species ranges is a critical research question in evolutionary ecology. We ask whether present intraspecific diversity is determined by the imprint of past climate. This is an ongoing debate requiring interdisciplinary examination of population genetic pools and persistence patterns across global ranges. Previously, contrasting inferences and predictions have resulted from distinct genomic coverage and/or geographical information. We aim to describe and explain the causes of geographical contrasts in genetic diversity and their consequences for the future baseline of the global genetic pool, by comparing present geographical distribution of genetic diversity and differentiation with predictive species distribution modelling (SDM) during past extremes, present time and future climate scenarios for a brown alga, Fucus vesiculosus. SDM showed that both atmospheric and oceanic variables shape the global distribution of intertidal species, revealing regions of persistence, extinction and expansion during glacial and postglacial periods. These explained the distribution and structure of present genetic diversity, consisting of differentiated genetic pools with maximal diversity in areas of long-term persistence. Most of the present species range comprises postglacial expansion zones and, in contrast to highly dispersive marine organisms, expansions involved only local fronts, leaving distinct genetic pools at rear edges. Besides unravelling a complex phylogeographical history and showing congruence between genetic diversity and persistent distribution zones, supporting the hypothesis of niche conservatism, range shifts and loss of unique genetic diversity at the rear edge were predicted for future climate scenarios, impoverishing the global gene pool.

Endovascular treatment of extracranial vertebral artery aneurysm and aberrant right subclavian artery aneurysm.

We report an endovascular approach that used to treat a symptomatic extracranial vertebral artery aneurysm associated to an asymptomatic aberrant right subclavian artery aneurysm. A 54-year-old man presented with neck pain, vertigo and loss of balance. The computed tomography (CT) scan demonstrated a left extracranial vertebral artery aneurysm that compressed and eroded the C5 vertebra associated to an aberrant right subclavian artery aneurysm. Endovascular exclusion of the vertebral aneurysm using a covered stent and a hybrid treatment of the aberrant subclavian artery aneurysm were performed. The 13th month follow-up CT scan confirmed the stent-grafts and supra-aortic vessels patency. The endovascular treatment represents a good option for these complex pathologies with excellent immediate results, reduces the complication rate and the hospital stay if compared to open repair. Long-term follow-up is necessary. To our knowledge this is a unique case in the literature.

New highly polymorphic microsatellite markers for the aquatic angiosperm Ruppia cirrhosa reveal population diversity and differentiation.

Ruppia cirrhosa is a clonal monoecious plant phylogenetically associated to seagrass families such as Posidoniaceae and Cymodoceaceae. It inhabits shallow waters that are important for productivity and as a biodiversity reservoir. In this study, we developed 10 polymorphic microsatellite loci for R. cirrhosa. Additionally, we obtained cross-amplification for two microsatellites previously described for Ruppia maritima. These 12 markers were tested in four R. cirrhosa populations from the southwest of Europe. The number of alleles per locus was high for most of the markers, ranging from 4 to 13. Two populations (Sicily and Cádiz) showed heterozygote deficit (p < 0.001). The four populations (Sicily, Murcia, Cádiz, and Tavira) were significantly differentiated (F(ST) ≠ 0; p < 0.001), corroborating the usefulness of these microsatellites on R. cirrhosa population genetics.

Percutaneous endovascular aneurysm repair with the ultra-low profile Ovation Abdominal Stent-Graft System.

AIM: Aim of the study was to report our single-center experience of the ultra-low profile OvationTM Abdominal Stent-Graft System with totally percutaneous endovascular aneurysm repair (PEVAR). METHODS: Between December 2010 and March 2013 we electively treated 35 patients (male: 89%, mean age: 73±7 years) with abdominal aortic aneurysm (AAA) using bilateral PEVAR with the OvationTM endograft. Most (77%) cases were characterized by challenging femoral artery anatomy. Patients returned for follow-up visits at 1, 3, 6 months and annually thereafter. RESULTS: Technical success was 97.1%. One type Ia endoleak was identified on final angiography, which was treated with an extension cuff. No groin complications were observed, including lymphocele, hematoma, pseudoaneurysm, dehiscence, or wound infection. Mean follow-up was 10 months (range 1-24 months). No death was registered. One type Ia endoleak was identified at the 12-month follow-up, which resolved with placement of a Palmaz balloon-expandible stent. No type II, III, or IV endoleaks were identified. No migration, AAA enlargement, AAA rupture, or conversion to open surgery was reported. Two patients (5.7%) developed monolateral iliac limb occlusion at 58 and 72 days of follow-up, respectively. In one case a limb kinking was observed and treated with iliac kissing stent. The other limb occlusion was due to external iliac artery severe stenosis and was treated with thrombolysis and iliac artery stenting. CONCLUSION: PEVAR with the OvationTM endograft is feasible and safe in patients with unfavorable anatomy.

Endovascular stenting of the ascending aorta for type A aortic dissections in patients at high risk for open surgery.

BACKGROUND: Open repair is the gold standard for type A aortic dissection (TAAD). Endovascular option has been proposed in very limited and selected TAAD patients. We report our experience with endovascular TAAD repair. METHODS: Inclusion criteria were: (1) entry tear in the ascending aorta; (2) proximal landing zone of at least 2 cm; (3) distance between entry tear and brachio-cephalic trunk of at least 0.5 cm; (4) no signs of cardiac tamponade or severe aortic regurgitation and (5) no signs of aortic branches ischaemia. Patients with cardiac revascularisation from ascending aorta were excluded. RESULTS: From April 2009 to June 2012, 37 patients with TAAD were admitted to our hospital. As many as 28 underwent surgical repair and 9 were considered at high surgical risk in a multidisciplinary meeting. Four met our inclusion criteria for an endovascular approach. Two of them had previous ascending aortic repair for TAAD and one had aortic valve replacement. Technical success was achieved in 100% of the patients. No mortality was registered during a median follow-up of 15 months (range 4-39 months), no migration of the graft and complete false lumen thrombosis of the ascending aorta in three patients. CONCLUSION: Endovascular treatment of TAAD is challenging but feasible in a selected subset of patients. Further research remains mandatory.

Evolution and diversification within the intertidal brown macroalgae Fucus spiralis/F. vesiculosus species complex in the North Atlantic.

We examined 733 individuals of Fucusspiralis from 21 locations and 1093 Fucusvesiculosus individuals from 37 locations throughout their northern hemisphere ranges using nuclear and mitochondrial markers. Three genetic entities of F. spiralis were recovered. In northern and sympatric populations, the presence of "F. spiralis Low" in the mid-intertidal and "F. spiralis High" in the high-intertidal was confirmed and both co-occurred with the sister species F. vesiculosus. The third and newly-discovered entity, "F. spiralis South", was present mainly in the southern range, where it did not co-occur with F. vesiculosus. The South entity diverged early in allopatry, then hybridized with F. vesiculosus in sympatry to produce F. spiralis Low. Ongoing parallel evolution of F. spiralis Low and F. spiralis High is most likely due to habitat preference/local selection and maintained by preferentially selfing reproductive strategies. Contemporary populations of F. spiralis throughout the North Atlantic stem from a glacial refugium around Brittany involving F. spiralis High; F. spiralis South was probably unaffected by glacial episodes. Exponential population expansion for F. vesiculosus began during the Cromer and/Holstein interglacial period (300,000-200,000 yrs BP). Following the last glacial maximum (30,000-22,000 yrs BP), a single mtDNA haplotype from a glacial refugium in SW Ireland colonized Scandinavia, the Central Atlantic islands, and the W Atlantic.

A NOTES approach for thoracic surgery: transgastric thoracoscopy via a diaphragmatic incision in a survival porcine model.

AIM: Recently the NOTES approach has been extended to mediastinum by a transesophageal access and to the thorax by a transvescical endoscopic approach. The aim of this study was to assess the feasibility and the safety of transgastric endoscopic approach to the thoracic cavity, with lung biopsy, in a survival porcine model. METHODS: The study was performed on four 20-30 kg female pigs (Sus scrofus domesticus). Following gastric wall incision, the muscular pars of the left diaphragmatic dome was incised along with the parietal pleura and the endoscope advanced into the thoracic cavity. In all animals, a thoracoscopy was performed as well as peripheral lung biopsy. At the end of the operation the endoscope was withdrawn from the thoracic cavity after pleural sac decompression and the diaphragmatic incision closed by endoscopic clips under maximal expansion of lungs. The gastric incision was finally closed by endoscopic clips. Chest-tube placement was not utilized. Animals were sacrificed by day 15 postoperatively. RESULTS: The gastroscope was easily introduced into the thoracic cavity that allowed to visualize the pleural cavity and to perform simple surgical procedures such as lung biopsies without complications. There were neither respiratory distress episodes nor surgical complications to report. No adverse event occurred during the survival period. The postmortem examination 15 days after surgery revealed a good closure of the diaphragmatic incision. At necropsy, the lung biopsies were completely healed. There were no signs of infection in both thoracic and peritoneal cavities. The length of follow-up and number of animals studied might have not been sufficient. CONCLUSION: This study demonstrates the feasibility of transgastric thoracoscopy in porcine model. Long-term follow-up of much larger series will be necessary for provision of more reliable answers if this approach should be adopted in the future and eventually translated for humans with advantages for patients.