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The study of fatty acid biomarkers in trophic structures at sub-polar latitudes is fundamental in describing energy fluxes across ecosystems characterized by complex inter-specific interactions. Due to the presence of certain essential fatty acids obtained exclusively from predator–prey interactions, fatty acid biomarkers are widely used to identify trophic interactions. This study analyzed fatty acid compositions in three species inhabiting a relatively pristine Patagonian fjord. This fjord is geographically difficult to access, so there are very little sampling opportunities, biological and oceanographic information. In the three species collected (Ctenodiscus australis (Loven in Lutken 1871) (Echinodermata, Asteroidea, Ctenodiscidae); Munida gregaria (Fabricius 1793) (Arthropoda, Malacostraca, Munididae); Eleginops maclovinus (Cuvier 1830) (Chordata, Actinopterygii, Eleginopsidae)) along this remote area were evaluated their fatty acid trophic markers as a tool to differentiate dietary components and dietary habits. The study reported significant differences in the amount of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA), with the highest concentrations of all fatty acids in M. gregaria. The last suggests that M. gregaria is considered as a good quality food source or biological component that might support the fjord trophic web in the Southern Hemisphere. The results describe diet compositions in sampled species, and differences among species for fatty acid compositions and proportions. This provides an initial basis for future modeling or projecting how benthic ecosystems of fjords and Patagonian channels respond to food intake, particularly in environments associated with glacial systems characterized by a low phytoplankton biomass and greater sensitivity to climate variability.

Introduction: Ventriculo-Peritoneal Shunt (VPS) related ascites is a rare complication of pediatric Low Grade Gliomas (pLGG). Physiopathology of this complication is not fully understood and there is paucity of data regarding the molecular profile of pLGG gliomas complicating with ascites and the optimal management of this unusual event. Methods: International multi-institutional retrospective analysis of patients diagnosed with BRAF altered pLGG and ascites arising as a complication of VPS. Demographics, tumor characteristics, therapeutic approaches and outcomes were recorded. Results: Nineteen patients were identified. Median age at diagnosis was 14 months (IQR:7-16). Most patients (16;84.2%) presented with lesions involving the optic pathway. Mean tumor standard volume was 34.8 cm2 (range:12.5-85.4). Pilocytic Astrocytoma was the most frequent histological diagnosis (14;73.7%). Eight (42.1%) tumors harbored BRAF V600-E mutation and seven (36.8%) KIAA1549 fusion. The onset of ascites was documented at a median time of 5 months following VPS insertion. Four (21%) patients were managed with paracentesis only, 7(36.8%) required both paracentesis and shunt diversion, 7(36.8%) required only a shunt diversion and 1 (5,2%) patient was managed conservatively. Ascites was the indication to change chemotherapy regimen in 10 patients. Eight patients received targeted therapy (4 dabrafenib/4 trametinib) and 5 were radiated. Eleven patients were alive at the time of this report with a median OS of 69 months (range:3-144). Conclusions: Ascites is an early feature in the course of pLGG irrespective of alterations in the RAS/MAPK pathway with high mortality rate and should be considered as an adverse prognostic risk factor in pLGG.

Ventriculo-peritoneal shunt (VPS) related ascites is a rare complication of pediatric low grade gliomas (pLGG). Physiopathology of this complication is not fully understood and there is paucity of data regarding the molecular profile of pLGG gliomas complicating with ascites and the optimal management of this unusual event.International multi-institutional retrospective analysis of patients diagnosed with BRAF altered pLGG and ascites arising as a complication of VPS. Demographics, tumor characteristics, therapeutic approaches and outcomes were recorded.Nineteen patients were identified. Median age at diagnosis was 14 months (R: 2-144). Most patients (17; 89.4%) presented with lesions involving the optic pathway. Mean tumor standard volume was 34.8 cmAscites is an early feature in the clinical course of young patients with midline BRAF altered pLGG, with high mortality rate observed in our cohort. The hypothesis of ascites as an adverse prognostic factor in pLGG warrants further prospective research.

The Baker-Martinez fjord system (Chile, 48°S) is a transitional environment between the terrestrial ecosystems of Patagonia and the SE Pacific Ocean. This unique setting makes it an ideal system to evaluate land-ocean gradients in sediment composition and in a range of biogeochemical variables. Here, we studied the composition and organic geochemistry of surface sediments deposited in the Baker-Martinez fjord system to assess spatial changes in sediment properties and identify the best tracers of terrestrial input. We determined concentrations in biogenic opal, organic carbon, calcium carbonate, and lithogenic particles, and we measured diatom abundance, bulk elemental and isotopic organic geochemistry, and n-alkanes distribution, on a series of surface sediment samples distributed along two proximal-to-distal transects (one in the Martinez Channel and a second one in the Baker Channel). Results reveal clear proximal-to-distal trends in the proportion of freshwater diatoms and in the fraction of organic carbon of terrestrial origin calculated from the bulk organic δ13C measurements. Diatoms are particularly sensitive to freshwater input in proximal environments, whereas bulk organic geochemistry better reflects terrestrial input over long distances across the fjord system. Other terrestrial proxies frequently used in the literature, such as the N/C ratio and the n-alkane-based terrestrial/aquatic ratio, did not show clear variations with distance from the fjord head. Our results suggest that the isotopic composition of bulk organic matter (δ13Corg) and the relative proportion of diatoms of freshwater origin are the best-suited proxies to estimate past changes in terrestrial input from fjord sediment archives, irrespective of the glacial status of the fjord and its watershed.

Stable isotopes and geochemical proxies (TOC/TN and Chla/TOC) in sediments can be used to distinguish organic matter sources (anthropogenic, terrestrial, or marine). This study aims to characterize organic matter (OM) in superficial sediments from three sectors of central Chile (33°S) that are highly influenced by urban and industrial development. Our results show that a substantial fraction of these OM in Quintero Bay is anthropogenic, from industrial and domestic wastewater sources. In contrast, a mixture of terrestrial and anthropogenic OM dominates the isotopic signal of surface sediments from Concón, derived from non-point industrial and agriculture sources associated with the Aconcagua River basin, while Ritoque exhibited a mixture of different OM sources. However, deposition of allochthonous OM in our study area depends on coastal topography, which influences the local currents and well-ventilated waters, promoting the dispersion and assimilation of OM and thus providing an environment with a high capacity for natural remediation.

BACKGROUND: High-grade gliomas (HGG) with replication-repair deficiency (RRD) harbour high mutation burden (TMB) and are rapidly fatal following chemo-radiation approaches. Although hypermutation results in objective responses and prolonged survival in >30% of patients undergoing PD1-blockade, salvage following failure of PD1-inhibition remains a challenge. METHODS: We performed a real-world study of Ipilimumab (anti-CTLA4) in combination with Nivolumab/Pembrolizumab for patients failing single-agent PD1-inhibition. RESULTS: Among 68 consortium patients with relapsed HGG treated with single-agent PD1-inhibitors, progression was observed in 43 (63%). Ipilimumab was added to 20/43 (46.5%), 14 (32.5%) received best supportive care (BSC), and 9 (21%) received miscellaneous therapies. For patients receiving CTLA4/PD1-inhibition, median age at progression was 12.3-years (IQR: 9; 15.6). Time from anti-PD1 initiation to progression was 8-months (IQR: 3.8; 18.5). Germline predisposition was observed in all patients (CMMRD: 70%, Lynch: 25%, polymerase-proofreading deficiency: 5%). All HGG were hypermutant (median TMB: 182 mutations/Mb; IQR: 15.6; 369.4). Centralized radiology review revealed objective responses in 3/20 (15%, all ultra-hypermutant: 320, 496, 834 mutations/Mb), stable disease in 5 (25%), and 12 (60%) eventually progressed (iRANO). Following failure of PD1-blockade, estimated progression-free and overall survival at 18-months for patients receiving CTLA4/PD1-inhibition were 11% and 25%, respectively. Importantly, survival was superior to patients receiving BSC (median OS 1-year on the anti-CTLA4/PD1combination (range:1-48 months). The combinational immunotherapy resulted in significant autoimmune toxicity in 11/20 (55%), warranting immunosuppressive therapy in all, and treatment abandonment in 6 patients. CONCLUSION: Combined CTLA4/PD1-blockade after failure of single-agent PD1-inhibition revealed objective responses and prolonged survival in an otherwise rapidly-fatal disease. This needs to be assessed in the context of significant autoimmunity, supporting the need for the current prospective trial (NCT04500548), and novel strategies to limit treatment-related toxicity.

The Eastern South Pacific coastal zone is characterized by seasonal and interannual variability, driven by upwelling and El Ni&ntilde, o Southern Oscillation (ENSO), respectively. These oceanographical conditions influence microbial communities and their contribution to nutrient and greenhouse gases recycling, especially in bottom waters due to oxygenation. This article addresses the seasonal hydrographic and biogeochemical conditions in the water and sediments during El Ni&ntilde, o 2015. Bottom water active microbial communities, including nitrifiers, were studied using amplicon sequencing of 16S rRNA (cDNA) and RT-qPCR, respectively. The results of the hydrographic analysis showed changes in the water column associated with the predominance of sub-Antarctic Waters characterized by warmed and low nutrients in the surface and more oxygenated conditions at the bottom in comparison with El Ni&ntilde, o 2014. The organic matter quantity and quality decreased during fall and winter. The bottom water active microbial assemblages were dominated by archaea (Ca. Poseidoniales) and putative ammonia oxidizing archaea. Active bacteria affiliated to SAR11, Marinimicrobia and Nitrospina, and oxygen deficient realms (Desulfobacterales, SUP05 clade and anammox) suffered variations, possibly associated with oxygen and redox conditions in the benthic boundary layer. Nitrifying functional groups contributed significantly more during late fall and winter which was consistent with higher bottom water oxygenation. Relationships between apparent oxygen utilization nitrate and nitrous oxide in the water support the contribution of nitrification to this greenhouse gas distribution in the water. In general, our study suggests that seasonal oceanographic variability during an El Ni&ntilde, o year influences the microbial community and thus remineralization potential, which supports the need to carry out longer time series to identify the relevance of seasonality under ENSO in Eastern Boundary Upwelling Systems (EBUS) areas.

Fjord ecosystems are located in high latitude environments across Scandinavia, Alaska, Canada, Chile, New Zealand, and some more northerly Antarctic and Arctic environments (Freeland et al. 1980). Fjords are water bodies with variable-depth estuarine features, are highly stratified, and are influenced by tidal currents (Pickard 1961; Wassmann et al. 2000). One of the largest regions of fjords in the world is the Chilean Patagonia (from 41º to 56ºS), stretching over 241,000 Km2 with islands, channels, estuaries, bays and gulfs formed by glacial erosion over the current quaternary (Borgel 1970; Holtedahl 2006; Aracena et al. 2015). This fjord region is characterized by low concentrations of dissolved inorganic nutrients in surface waters, and high concentrations of nutrients supplied by sub-Antarctic ocean waters (Silva et al. 1997, 1998; Silva 2008; González et al. 2011). Stratification in the water column is a barrier that reduces the export of phytoplanktonic carbon and influences the distribution of some zooplankton groups (Ji et al. 2010; González et al. 2011; Tamelander et al. 2012). Fjords are important sites for carbon cycles and biological productivity (Wetzel 2001; González et al. 2006; Pomeroy 2006), and are sensitive to environmental and climatic changes (Overpeck et al. 1997; Svendsen et al. 2002; Whitehead et al. 2009).

PURPOSE Children with pediatric gliomas harboring a BRAF V600E mutation have poor outcomes with current chemoradiotherapy strategies. Our aim was to study the role of targeted BRAF inhibition in these tumors. PATIENTS AND METHODS We collected clinical, imaging, molecular, and outcome information from patients with BRAF V600E–mutated glioma treated with BRAF inhibition across 29 centers from multiple countries. RESULTS Sixty-seven patients were treated with BRAF inhibition (pediatric low-grade gliomas [PLGGs], n = 56; pediatric high-grade gliomas [PHGGs], n = 11) for up to 5.6 years. Objective responses were observed in 80% of PLGGs, compared with 28% observed with conventional chemotherapy ( P < .001). These responses were rapid (median, 4 months) and sustained in 86% of tumors up to 5 years while receiving therapy. After discontinuation of BRAF inhibition, 76.5% (13 of 17) of patients with PLGG experienced rapid progression (median, 2.3 months). However, upon rechallenge with BRAF inhibition, 90% achieved an objective response. Poor prognostic factors in conventional therapies, such as concomitant homozygous deletion of CDKN2A, were not associated with lack of response to BRAF inhibition. In contrast, only 36% of those with PHGG responded to BRAF inhibition, with all but one tumor progressing within 18 months. In PLGG, responses translated to 3-year progression-free survival of 49.6% (95% CI, 35.3% to 69.5%) versus 29.8% (95% CI, 20% to 44.4%) for BRAF inhibition versus chemotherapy, respectively ( P = .02). CONCLUSION Use of BRAF inhibition results in robust and durable responses in BRAF V600E–mutated PLGG. Prospective studies are required to determine long-term survival and functional outcomes with BRAF inhibitor therapy in childhood gliomas.

Benthic marine food webs, which recycle organic matter and sustain unique biodiversity, are an important component of estuarine Patagonian fjords; however, these may be heavily influenced by salmon farming activities. Under the above conditions, this study collected several food sources (sediment organic matter, suspended particulate organic matter, macroalgae) and 26 benthic invertebrate species, and analyzed them using a Bayesian mixing model. Briefly, carbon and nitrogen stable isotopes analyses revealed that the highly variable isotopic niche widths respond to food supplies from marine and terrestrial organic matter. In addition, particulate and dissolved waste from salmon farming activities were found to modify isotopic composition ratios in many suspension feeders. Particularly, our results indicate high δ15N values in the sponge Cliona chilensis and the encrusting coral Incrustatus comauensis, which appear to be potential ecological indicators for evaluating stoichiometry imbalances and trace organic pollution sources in fjord environments.

espanolEn este articulo se estudia un Control Vibratorio Activo (AVC) para un problema de tres carritos. Se comparan los algoritmos de minimos cuadrados filtrados (FxLMS) y minimos cuadrados recurrentes (RLS) en terminos de rechazo de perturbaciones, costo computacional y esfuerzo de control cuando se dispone de una medicion correlacionada de la perturbacion. El compensador RLS propuesto considera un acoplamiento de retroalimentacion entre el compensador y la perturbacion. La ruta de propagacion secundaria de la planta se estimo utilizando el algoritmo LMS normalizado (NLMS). El acoplamiento positivo interno se modela como un filtro FIR estimado por los parametros reales de la planta. Las simulaciones mostraron un rendimiento superior del algoritmo RLS con un costo informatico razonable. El analisis comparativo se realizo comparando la compensacion entre el orden del filtro y la magnitud del rechazo. EnglishIn this paper an Active Vibrational Control (AVC) for a three-cart problem is studied. The Filtered-x Least Mean Square (FxLMS) and Recursive Least Square (RLS) algorithms are compared in terms of disturbance rejection, computational cost and control effort when a correlated measurement of the disturbance is available. The proposed RLS compensator considers a feedback coupling between the compensator and the disturbance. The secondary propagation path of the plant was estimated using normalized LMS (NLMS) algorithm. The internal positive coupling is modeled as a FIR filter estimated by the real plant parameters. Simulations showed a superior performance of RLS algorithm with a reasonable computer cost. The comparative analysis was performed comparing the tradeoff between the filter order and the magnitude of the rejection.

Background Controversy exists as to what may be defined as standard of care (including markers for stratification) for patients with atypical teratoid/rhabdoid tumors (ATRTs). The European Rhabdoid Registry (EU-RHAB) recruits uniformly treated patients and offers standardized genetic and DNA methylation analyses. Methods Clinical, genetic, and treatment data of 143 patients from 13 European countries were analyzed (2009–2017). Therapy consisted of surgery, anthracycline-based induction, and either radiotherapy or high dose chemotherapy following a consensus among European experts. Fluorescence in situ hybridization, multiplex ligation-dependent probe amplification, and sequencing were employed for assessment of somatic and germline mutations in SWItch/sucrose nonfermentable related, matrix associated, actin dependent regulator of chromatin, subfamily B (SMARCB1). Molecular subgroups (ATRT-SHH, ATRT-TYR, and ATRT-MYC) were determined using DNA methylation arrays, resulting in profiles of 84 tumors. Results Median age at diagnosis of 67 girls and 76 boys was 29.5 months. Five-year overall survival (OS) and event-free survival (EFS) were 34.7 ± 4.5% and 30.5 ± 4.2%, respectively. Tumors displayed allelic partial/whole gene deletions (66%; 122/186 alleles) or single nucleotide variants (34%; 64/186 alleles) of SMARCB1. Germline mutations were detected in 26% of ATRTs (30/117). The patient cohort consisted of 47% ATRT-SHH (39/84), 33% ATRT-TYR (28/84), and 20% ATRT-MYC (17/84). Age Conclusions Age and molecular subgroup status are independent risk factors for survival in children with ATRT. Our model warrants validation within future clinical trials.

Polychaetes were studied to assess the effect of aquaculture activity on the seafloor. Very high biodiversity of species was recorded associated with aquaculture centres with Cirratulidae, Spionidae and Paraonidae families being the most diverse and abundant families. The spatial distribution of polychaete trophic groups was the best descriptor for detecting changes on the benthos. Surface and subsurface deposit-feeding species dominated the sites closest to the rafts cages, highlighting Capitella capitata and Cirratulus cirratus as opportunistic species. While replacement and species succession were observed with increasing presence of carnivores and omnivores in sites further away from the salmon cages and experiencing less impact. Analyses based on the distance of feeding modes and ecological groups from the disturbance source were better indicators of the impact that the traditional community approach or sediment biogeochemistry. Therefore, functional traits studies should always be considered on environmental assessments of benthic systems impacted by aquaculture.

Complex marine-terrestrial interactions characterize Chilean fjords, where benthic communities influence the distribution of organic matter (OM). We examined spatial and seasonal changes in the hydrography, sediment conditions and soft-bottom macrobenthic, meiobenthic, and total microbial biomass in a glacial Patagonian fjord (Martinez Channel, Chile). The transport of a high load of glacial mineral and particulate OM to the fjord in the austral summer coincided with low total live benthic biomass. Multivariate analysis evidenced temporal-related macrofaunal groups influenced by the different environments produced by the advection of sediment transport and terrestrial OM from the Baker River, Chile. The relationships between density/biomass and respiration versus body size varied considerably with distance from major riverine inputs, but the slopes of density size spectra and normalized biomass size spectra were less negative in summer than in winter. Occasional large-scale advective processes in the water column affected sediment conditions and removed surface macrofauna, influencing the slope and intercept of the regression models. In the outer fjord, lateral advection and subsequent sedimentation of terrestrial OM contributed a significant fraction to total OM sediments (

The Patagonian fjords are high-latitude aquatic ecosystems, highly sensitive to climate change and play a key role in the exchange of organic matter and carbon flows between terrestrial and marine environments. The bioenergetic composition of species living in these ecosystems are fundamental to understanding the distribution, seasonal variations, and exchange of organic matter within benthic communities. This study reports on the bioenergetic characteristics (lipids, protein, glucose, and energy content) of three keystone species with different life-style and feeding habits: a benthic sea star (Ctenodiscus australis); squat lobster (Munida gregaria); and a Patagonian notothenioid (Eleginops maclovinus). Samples were obtained from the Yendegaia Fjord (54°40'S - 68°50′W) in Chilean Patagonia. Our results indicate that M. gregaria has higher concentrations of lipids, proteins, glucose, and total energy compared to either E. maclovinus or C. australis. The predominance of lipids in all species is possibly related to physiological characteristics and feeding strategies. Also, may be associated with the availability of food and environmental conditions typical of a fjord ecosystem and the reproductive stage in that they were collected. These results suggest that marine animals inhabiting glacially influenced environments with low temperature and low productivity, requires a convergent physiological strategy characterized by high levels of energy storage (i.e. lipids) for metabolism and key bioenergetic processes such as growth and reproduction.

Children with pediatric gliomas harboring BRAF V600E mutation have a poor outcome with current chemoradiation strategies. Our aim was to study the role of targeted BRAF inhibition in these tumors. We collected clinical, imaging, molecular and outcome information from BRAF V600E glioma patients treated with BRAFi across 29 centers from multiple countries. Sixty-seven patients were treated with BRAFi (56 pediatric low grade gliomas, PLGG and 11 pediatric high grade gliomas, PHGG) for up to 5.6 years. Objective responses were observed in 80% of PLGGs compared to 28% with conventional chemotherapy (p

AT/RT is a challenging entity due to a dearth of controlled clinical trials and lack of biological samples. We aimed to identify clinical and molecular risk factors in a carefully characterised series of AT/RT. METHODS: We enrolled 142 patients from 13 European countries (06/2009 to 08/2017). Median age at diagnosis was 17,5 months (25(th) /75(th) percentile: 9/26,5 months). Therapy followed a consensus regimen. Tumors were investigated for SMARCB1 and SMARCA4 mutations using FISH, MLPA and/or sequencing (n=87/142). Blood was examined for germline mutations (GLM) (n=114/142). Molecular subgroups (ATRT-TYR, -SHH or -MYC) were determined in tumors using Illumina BeadChip based DNA-methylation profiling (n=102/142). RESULTS: Preliminary 5y-OS- and EFS-estimates of this cohort are 20 ± 5% and 26 ± 5%. In a multivariate model, patients (a) below 1 year at diagnosis with (b) M+-disease, (c) synchronous tumours and (d) incomplete resection (no GTR) had the worst prognosis (p

El trabajo analiza la gestión de la competitividad de Argentina en el mercado mundial de la carne vacuna a través de un análisis integral tendiente a evaluar el desempeño de los actores en cada etapa de la cadena de valor, la eficiencia con que se vinculan los distintos eslabones de la misma, la disponibilidad y racionalidad en el uso de los recursos, los condicionantes del entorno económico-político-institucional, y las implicancias para las empresa y el gobierno en el actual contexto competitivo. Argentina posee importantes ventajas comparativas para la producción ganadera, dada la abundancia de sus recursos naturales, pero estas ventajas no se han transformado en ventajas competitivas sustentables. En los diferentes apartados se pretende captar la complejidad de los diferentes factores que afectan la estructura del mercado internacional y la competitividad de la industria cárnica argentina, para culminar con el planteo de recomendaciones de políticas posibles, a modo de propuestas de soluciones parciales, que pretenden contribuir con acciones concretas, al diseño de un plan integral de desarrollo estratégico del sector. Argentina necesita implementar un plan integral para promover un ambiente de negocios propicio para atraer inversiones que aumenten la productividad y la eficiencia a lo largo de toda la cadena, reducir los costos de transacción, y recuperar la imagen y el posicionamiento en los mercados externos., Facultad de Ciencias Económicas

The Scotia Arc is the only shallow-water and island bridge linking nowadays Patagonia and the Antarctic. The Antarctic Circumpolar Current as an oceanographic peculiarity makes this region an interesting biogeographic transition zone, because this frontal system traditionally is said to isolate the Antarctic fauna from that of the adjacent northern ecosystems. Based on benthos samples from three expeditions onboard R/V Polarstern, we studied distribution patterns of 200 polychaete species and 34 major benthic taxa in order to evaluate the role of polychaetes in the benthic realm of this part of the Southern Ocean. ANOSIM test distinguished three station groups: the central eastern Scotia Sea, the continental shelf off South America and stations at the tip of the Antarctic Peninsula. These station groups differed in organism densities and diversities with stations at the tip of the Antarctic Peninsula hosting the most diverse and dense community. The polychaete diversity patterns in the three assemblages evidenced closer connectivity between the tip of the Antarctic Peninsula and the central eastern Scotia Sea than between the continental shelf off South America with either the stations off the tip of the Peninsula or the central eastern Scotia Sea. This is probably supported by the Polar Front, which divides the island chain into two branches. Species distribution and community patterns of polychaetes appear to be associated with oceanographic and sediment conditions in this region. Most of the shared species showed the capability to tolerate differences in hydrostatic pressure. We suggest that the islands of the Scotia Sea may constitute a bridge for exchange of benthic species, particularly for polychaetes with eurybathic distribution and high dispersal capabilities.

Non-medulloblastoma CNS embryonal tumors (former PNET/Pineoblastomas) are aggressive malignancies with poor outcome that have been historically treated with medulloblastoma protocols. The purpose of this study is to present a tumor-specific, real-world data cohort of patients with CNS-PNET/PB to analyze quality indicators that can be implemented to improve the outcome of these patients. Patients 0-21 years with CNS-PNET treated in eight large institutions were included. Baseline characteristics, treatment and outcome [progression-free and overall survival (PFS and OS respectively)] were analyzed. From 2005 to 2014, 43 patients fulfilled entry criteria. Median age at diagnosis was 3.6 years (range 0.0-14.7). Histology was pineoblastoma (9%), ependymoblastoma (5%), ETANTR (7%) and PNET (77%). Median duration of the main symptom was 2 weeks (range 0-12). At diagnosis, 28% presented with metastatic disease. Seventeen different protocols were used on frontline treatment; 44% had gross total resection, 42% craniospinal radiotherapy, 86% chemotherapy, and 33% autologous hematopoietic stem cell transplantation (aHSCT). Median follow-up for survivors was 3.5 years (range 1.7-9.3). 3-year PFS was 31.9% (95% CI 17-47%) and OS 35.1% (95% CI 20-50%). Age, extent of resection and radiotherapy were prognostic of PFS and OS in univariate analysis (p < 0.05). Our series shows a dismal outcome for CNS-PNET, especially when compared to patients included in clinical trials. Establishing a common national strategy, implementing referral circuits and collaboration networks, and incorporating new molecular knowledge into routine clinical practice are accessible measures that can improve the outcome of these patients.

Burkitt lymphoma (BL) is highly FDG-avid even though its usefulness in the management of these patients is still controversial. Aim We analyzed the role of positron emission tomography/computerized tomography (PET/CT) in staging newly diagnosed patients with BL and evaluating disease after first-line chemotherapy. Methods Fifty-two PET/CTs were performed in 32 patients (20 at diagnosis, 27 after treatment, five to monitor residual disease). Involved areas were retrospectively compared with those observed in contrast-enhanced CT. Results Discrepancies were found in 64.7% of patients for whom results of both tests at diagnosis were available (n = 17), most of them involving extranodal sites. Regarding response assessment, discrepancies were observed in 38% of patients with both tests (5/13): residual masses detected by CT with negative PET/CT. Of 27 patients with post-treatment PET/CT, 22 were in complete remission whereas one true-positive and four false-positive lesions (two nodal and two extranodal) were detected. With a median follow-up of 27 months, 22 patients with negative PET/CT did not relapse. Thus, negative predictive value (NPV) was 100%. With respect to positive predictive value (PPV), one of five patients with positive assays after treatment died due to progression while the remaining four had false-positive lesions. Nevertheless, for these four patients, mean SUVmax at nodal sites was 4.1 vs. 14.9 at diagnosis, while mean SUVmax at extranodal sites was 3.8 vs. 12.1. Thus, with a cutoff value for SUVmax

Food web studies have provided insight into the dynamics of benthic ecosystems and their stability, stimulating research into the importance of different organic matters (OM) inputs in the ecological and metabolic processes that affect community structure. Using stable isotope analysis (SIA) and Bayesian ellipses, this study examines the influence of terrestrial OM and hydrographic conditions on food web structure and niche width in a glacial system (Baker/Martinez fjord complex). Two ecological groups were identified; one located in the inner and middle fjord and the other one in the outer fjord. Both had isotopically less diverse feeding groups in comparison to non-glacier benthic communities, comprising four trophic levels. In addition, the study area exhibited high trophic redundancy (e.g., species with overlapping trophic niches) associated with chronic natural physical disturbances from glacial sedimentations, which have shaped this non-selective feeding benthic community. The trophic structure metrics suggest that the benthic food web is supported principally by primary production and terrestrial OM pathways, but macroalgal subsidies could be important to detritivores via floating kelp in the inner area of the fjord. The results of this study suggest that glaciofluvial benthic communities have higher trophic redundancy associated with environmental disturbance conducted by sediment load, shaping a benthic community with a lower alpha diversity and fewer trophic levels in comparison to no-glacier environments.

Two new distribution records of hermit crabs of the family Parapaguridae, i.e., Oncopagurus haigae and Sympagurus dimorphus are presented. The material examined was collected by 2 expeditions from the Chilean coast. The PUCK-156 and INSPIRE Expeditions in 2001 and 2010, respectively, at depths ranging from 340 to 1300 m. The present study provides taxonomic and distributional information as well as a key to aid in the identification of the species of Parapaguridae present in waters off Chile. With these results the family in southeast Pacific waters off Chile is represented by 14 species belonging to the genera Oncopagurus (3 species), Paragiopagurus (3 species), Parapagurus (3 species), Sympagurus (3 species), Strobopagurus (one species) and Tylaspis (one species).

OBJECTIVE: To retrospectively assess at national level whether the addition of molecular data to clinical/histopathological factors could have modified the initial risk factors for survival in children with medulloblastoma. METHODS: A 40 years (1975-2015) retrospective study of 218 patients (0-18 years) from 24 national hospitals was performed. Histology and molecular review, including CTNNB1 gene mutations (RT-PCR) p53(immunohistochemistry) and MYCC/MYCN (FISH), was centralized. The patients were reclassified as standard (SR) or high-risk (HR) according to current knowledge. RESULTS: 187 cases had valid data. Median age 6.9 years (76%

The BRAF-V600E mutation is found in 15–20% of pediatric low grade gliomas (PLGG) and result in worse outcome and higher risk of transformation to high grade gliomas (PHGG). Although ongoing trials are assessing the role of BRAF inhibitors (BRAFi) in these children, data are still limited. We aimed to report overall response rates and predictors of outcome in childhood BRAF-V600E gliomas. We collected clinical, imaging and molecular information of patients treated with BRAFi outside trials from centers participating in the PLGG taskforce. Response was calculated by RANO criteria and follow up data were collected for all patients. Sixty-six patients were treated with BRAFi (55 PLGG and 11 PHGG); median follow-up time was 1.5 years (0.1-5y). In PLGG, objective response (tumor reduction of >25%) was observed in 77% compared to 15% in a cohort treated with conventional chemotherapy (pCDKN2A deletion was not associated with lack of response, while specific enhancing patterns correlated strongly with response to BRAFi. Two-year PFS for the BRAF-V600E PLGG was 74% vs 47% for BRAFi vs chemotherapy, respectively (p=0.02). Our data reveal rapid, dramatic and sustained response of BRAF-V600E PLGG to BRAFi. These are in contrast to BRAF-V600E PHGG and non-enhancing PLGG. Additional molecular analyses are being performed to identify poor responders and emerging mechanisms of resistance in these tumors.

Modification and channelization of streams and rivers have been conducted extensively throughout the world during the past century. Subsequently, much effort has been directed at re-creating the lost habitats and thereby improving living conditions for aquatic organisms. However, as restoration methods are plentiful, it is difficult to determine which one to use to get the anticipated result. The aim of this study was to compare two commonly used methods in small Danish streams to improve the physical condition: re-meandering and passive restoration through cease of maintenance. Our investigation included measurement of the physical conditions in 29 stream reaches covering four different groups: (1) re-meandered streams, (2) LDC streams (the least disturbed streams available), (3) passively restored streams (>10 years stop of aintenance) and (4) channelized and non-restored streams. The in-stream habitats were compared through analysis of the measured physical parameters and by applying a habitat model. We found that re-meandering is a more effectiveway of re-creating near-natural physical conditions in small streams compared to passive restoration. This is probably due to the limited energy in small streams which restricts re-shaping of the stream channel. However, based onhabitat suitability modelling, the change to the physical condition did not translate into improved habitat suitability for young of the year brown trout highlighting the value of using several methods when evaluating restoration success.

The AZTI's marine biotic index (AMBI), an ecological indicator for managing estuarine and coastal waters worldwide, was tested in two fjords in Chilean Patagonia. The Aysen Fjord (42° Lat. S) supports intensive salmon farming in coastal ecosystems, while the Baker Fjord (48° Lat. S) is currently just beyond the limit of the southern expansion of salmon concessions. The ecological status of the Aysen Fjord was classified as good, while the status of the Baker Fjord was classified as high and unbalanced. These differences were consistent with our expectations, illustrating the effect of local environmental conditions and human activities, combined with river inputs into semi-confined fjords. This method is appropriate for the evaluation of the ecological status of the fjords, but requires a sufficient amount of data for the robust environmental assessment as proposed by the Water Framework Directive (WFD).

Background : Respiratory insufficiency in children with life-limiting and life-threatening conditions is common, it has a lasting impact, yet there is a paucity of evidence to guide clinicians in its management with home support. Objectives : Our aim was to review palliative indication of home mechanical ventilation (HMV) in Southwestern Spain. Methods : Descriptive cross-sectional study including pediatric patients (aged 0 to 18 years) who were being taken care by the HMV program at the University Hospital Virgen del Rocio in Seville between 2000 and 2015. Results : A total of 78 patients were analyzed, 22 on invasive ventilation (10 with 24 hours/day) and 56 on no invasive ventilation. Duration of HMV varies from 2 days to 15 years. According to standards for pediatric palliative care in Europe, 12 patients suffered from life-threatening illness, (group 1; 4 cancer, 8 no progressive lung disease), 17 had conditions in which premature death is inevitable (group 2; 3 mucopolysaccharidosis, 14 malformative syndrome or chromosomopathy), 38 had progressive conditions without curative options (group 3; 30 neuromuscular diseases, 8 neurological progressive disease of unknown origin), 7 had irreversible but not progressive conditions (group 4; cerebral palsy). When HMV was started 17 patients had severe cognitive impairment, and HMV was indicated to improve quality of life by reducing hospital visits. During follow up, 3 patients died and 3 were weaned from HMV (group 1). Only 4 patients were included in a pediatric palliative care program. Conclusions : Up to 95% of patients with HMV can benefit from palliative care. HMV in children with chronic conditions aims to ameliorate their quality of life, but may pose ethical dilemmas.

PNR-16. DIAGNOSIS, MANAGEMENT AND OUTCOME OF CHILDREN WITH CENTRAL NERVOUS SYSTEM (CNS) PRIMITIVE NEUROECTODERMAL TUMORS (PNET) IN SPAIN: A STUDY FROM THE SPANISH NATIONAL PEDIATRIC ONCOLOGY & HEMATOLOGY SOCIETY (SEHOP) Teresa de Rojas1, Francisco Jose Bautista1, Miguel Flores2, Victoria Fioravantti1, Lucia Igual3, Raquel Rubio4, Eduardo Bardon5, Lucia Navarro6, Laura Murillo7, Raquel Hladun8, Adela Canete3, Miguel Garcia4, Carmen Garrido5, Ana Fernandez-Teijeiro6, Eduardo Quiroga6, Carlota Calvo7, Anna Llort8, Luis Madero1, Ofelia Cruz2, and Lucas Moreno1; Hospital Infantil Universitario Nino Jesus, Madrid, Spain; Hospital Sant Joan deDeu,Barcelona, Spain; HospitalUniversitarioy Politecnico La Fe, Valencia, Spain; Hospital Universitario Cruces, Bilbao, Spain; Hospital General Universitario Gregorio Maranon, Madrid, Spain; Hospital Universitario Virgen del Rocio, Sevilla, Spain; Hospital Universitario Miguel Servet, Zaragoza, Spain; Hospital Universitario Vall d’Hebron, Barcelona, Spain BACKGROUND: CNS-PNET are aggressive embryonal tumors with poor outcome that have been historically treated in the context of medulloblastoma clinical trials. The purpose of this study is to present a tumor-specific, realworld data cohort of CNS-PNET. METHODS: Patients 0-21 years with CNS-PNET treated in 8 large institutions were included. Baseline characteristics, received treatment and outcomes [relapse-free and overall survival (RFS and OS respectively)] were analysed. RESULTS: From 2005 to 2014, 43 patients fulfilled entry criteria. Median age at diagnosis was 3.6 years (range 0.0-14.7). Histology was pineoblastoma (9%), ependymoblastoma (5%), ETANTR (7%) and PNET (79%). Median duration of the main symptom was 2 weeks (range 0-12). At diagnosis, 28% presented with metastatic disease. Primary tumor location was hemispheres (67%), pineal (12%), infratentorial (16.5%) and spinal cord (4.5%). Frontline treatment: 44% had gross total resection, 42% craniospinal radiotherapy, 86% chemotherapy with over 10 different strategies, and 33% autologous stem cell transplantation (aHSCT). Median follow-up for survivors was 3.5 years (range 1.7-9.3). 5-year RFS was 27.9% (95%CI 13-43%) and OS 30.7% (95%CI 16-46%). 73% of survivors had severe long-term sequelae. Age, M stage, extent of resection, radiotherapy and aHSCT were prognostic of OS in univariate analyisis (p , 0.05). CONCLUSIONS: Real-world data continues to show a dismal outcome for CNS-PNET despite advances in the field. In the current era, CNS-PNET is a distinct biological and genomic entity and new therapeutic strategies should be developed in multinational clinical trials. Neuro-Oncology 18:iii7–iii15, 2016. doi:10.1093/neuonc/now067.13 #The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The relationships between chlorophyll a concentration, physical-chemical variables (temperature, salinity, density, total suspended particulate matter) and nutrients (silicate, nitrate, nitrite and phosphate) were determined in the marine periglacial area of the Gallegos sound (54° 28’58’’S - 69° 50’55’’W) in August 2010 (austral winter). Twelve stations were studied out directly from the glacier edge to mouth of the sound. At each station, a CTD was deployed and water samples were collected. The water tempera-tures ranged from 3.74 to 6.55 °C, the salinity from 28.39 to 30.14 psu and chlorophyll a concentrations varied from 0.24 to 2.69 mg m-3; the total particulate matter concentrations varied between 0.12 and 14.0 mg L-1. The silicate concentrations varied between 2.58 and 9.57 µM, phosphate between 0.01 and 8.02 µM, and nitrate and nitrite values ranged from 0.02 to 30.34 µM and 0.01 to 2.99 µM, respectively. The chlorophyll a concentration in the sound was significantly correlated with depth, total particulate matter and density (ρ = 0.477), whereas lower correlation values resulted with silicate and phosphate (ρ = 0.463). The lowest significant correlation value was observed with nitrate concentrations (ρ = 0.397). Our result suggest that the water column stratification is linked to total particular matter maintaining high chlorophyll a concentrations in the euphotic layer of this cold water estuarine system. Se determinó la relación entre la concentración de clorofla a, las variables físico-químicas (temperatura, salinidad, densidad y solidos totales suspendidos) y nutrientes (silicatos, nitratos, nitritos y fosfatos) en el área periglaciar de seno Gallegos (54° 28’58’’S - 69° 50’55’’ W) en agosto del 2010 (invierno austral). Doce estaciones fueron estudiadas directamente desde el borde glaciar a la boca del seno Gallegos. En cada una de las estaciones se realizaron lances de CTD y se colectaron muestras de agua. La columna de agua en seno Gallegos presentó un rango de temperatura de 3,74 °C a 6,55 °C, el rango de salinidad fue de 28,39 a 30,14 psu y las concentraciones de clorofla a variaron desde 0,24 hasta 2,69 mg m-3; la concentración de solidos totales suspendidos varió entre 0,12 y 14,0 mg L-1. Las concentraciones de silicato variaron entre 2,58 hasta 9,57 µM, los fosfatos variaron de 0,01 a 8,02 µM, mientras que los valores de nitratos y nitritos variaron de 0,02 a 30,34 µM y 0,01 a 2,99 µM, respectivamente. Las concentraciones de clorofla a en el seno se correlacionaron significativamente con la profundidad, solidos totales suspendidos y la densidad (ρ = 0,477), mientras que valores bajos de correlación resultaron con los silicatos y fosfatos (ρ = 0,463). Los valores con menor correlación significativa fueron observados en los nitratos (ρ = 0,397). Nuestros resultados sugieren que la estratificación de la columna de agua se vincula con los solidos totales suspendidos manteniendo altas las concentraciones de clorofla a en la capa eufótica de estos sistemas estuarinos fríos.

In this study we describe community parameters such as densities, biomasses, species composition, feeding modes and normalized biomass size-spectra (NBSS) of macrobenthic invertebrate communities from three stations located in the Baker Fjord obtained on four seasonal campaigns in 2008 and 2009. The macrobenthic communities were dominated by small-bodied polychaetes (Paraonidae, Capitellidae and Cirratulidae) characterized by continuous year-round breeding, short life-spans, and fast turnover rates, which in turn regulated the standing stock in the communities. Principal component analysis and multiple-regression analysis demonstrate the distribution of macrobenthic communities in the study area to be mainly controlled by few local environmental conditions. Macrofaunal densities, diversity and feeding modes were significantly correlated with the total organic carbon (TOC; R2 = 0.74; P a (Chl-a; R2 = 0.55; P

The polychaete fauna of the Paso Ancho Basin in the Straits of Magellan was studied by means of three different sampling gears: a multibox corer, an Agassiz trawl, and a Rauschert dredge. A total of 1743 polychaete specimens belonging to 166 species from 36 families were collected at 10 stations. Significant differences were found between the catches of the three gears in terms of species numbers. The multibox corer brought up 63% of all species caught, especially macroinfauna polychaetes, the Rauschert dredge caught 16%, mostly small-bodied macroepifauna species and the Agassiz Trawl brought up 6% of the total species, largely mega-epifauna polychaetes. Only 15% of the total species occurred in more than one of the gears and only one species was found parallel in all three gears thus indicating that the combination of these gears allowed a better description of the polychaete communities than possible by just one of the gears. Using the Abundance-based Coverage Estimator and combining all species from the three different gears led to an asymptotic value of the species accumulation curve of 223 species for the Paso Ancho. Non-metric multidimensional scaling based on presence/absence data distinguished between shallow ( 120 m) polychaete assemblages. The shallow assemblage showed higher species richness values than the deep assemblage, and the taxonomical composition, too, differed considerably between both assemblages.