ADAPTANDO ESTRATEGIAS TERAPÉUTICAS PARA EL TRATAMIENTO DE OSTEOSARCOMA EN PEDIATRÍA: EXPERIENCIA COLABORATIVA DE LA ASOCIACIÓN DE HEMATO-ONCOLOGÍA PEDIÁTRICA DE CENTROAMÉRICA (AHOPCA)

El osteosarcoma es el cáncer óseo más frecuente en pediatría. Existe una marcada brecha en la sobrevida de sarcomas entre países emergentes y países desarrollados, relacionada con factores no biológicos del cáncer.En 1998, cuatro países centroamericanos se unen y con apoyo de especialistas de Europa y Norte América, conforman la Asociación de Hemato-Oncología Pediátrica de Centroamérica (AHOPCA), a fin de unificar estrategias terapéuticas, que permitan mejorar las tasas de sobrevida del cáncer pediátrico.Dentro de esta colaboración, se realiza un estudio observacional, descriptivo, retroprospectivo y de tipo analítico, durante 17 años, constituyendo el primer protocolo colaborativo AHOPCA-Osteosarcoma.Las variables analizadas fueron edad, sexo, extensión de enfermedad y tipo de cirugía. Se analiza sobrevida global y sobrevida libre de eventos, mediante pruebas de Kapplan-Meier con pruebas log Rank.Se diagnosticaron 485 nuevos casos de osteosarcoma en niños en los centros AHOPCA participantes y fueron evaluables 392 pacientes. Se registró una alta tasa de pacientes metastásicos (30%). Se observó una alta tasa de abandono y desacuerdo al control local (amputación). En la segunda era se modificó la estrategia terapéutica, introduciendo amputación de entrada, lo cual no demostró diferencia significativa en la sobrevida (p=0,69). En ambas eras la sobrevida fue inferior al 40%. Este estudio evidenció una marcada brecha en la sobrevida del osteosarcoma comparado, a lo reportado en países desarrollados. Se recomienda abordar más a fondo determinantes sociales que impactan negativamente en la sobrevida del osteosarcoma pediátrico en la regió

AVALIAÇÃO DA TÉCNICA DE SOLARIZAÇÃO ATRAVÉS DO MONITORAMENTO DO PERFIL DE TEMPERATURAS DO SOLO

O presente trabalho tem por objetivo avaliar a técnica de solarização aplicado no município de Cerro Largo/RS, através do monitoramento do perfil de temperaturas do solo e da obtenção de correlações para determinar a temperatura do solo em função da temperatura do ar. A solarização foi aplicada em uma unidade experimental de 4 m² de área. Para o monitoramento das temperaturas, efetuado tanto no terreno não solarizado quanto no local de aplicação da técnica, foram utilizados 8 termopares do tipo K conectados a um registrador de dados FieldLogger. O estudo analisou as temperaturas da superfície do solo e das profundidades 0,10 m, 0,25 m e 0,40 m, por um período de trinta e três dias. Correlações foram obtidas a partir do método de regressão linear, no qual foi ajustado uma reta para os dados amostrais e analisado o coeficiente de determinação ajustado (R²) para cada caso. Obteve-se a temperatura máxima de 33,34 ºC na superfície do solo que não recebeu o tratamento, e 36,72 ºC na superfície do solo solarizado. O coeficiente de determinação para a área que não recebeu solarização variou entre 0,50 e 0,61, enquanto que para o solo solarizado, o R² variou entre 0,36 e 0,63

Micro-Macro limit of a non-local generalized Aw-Rascle type model

International audienceWe introduce a Follow-the-Leader approximation of a non-local generalized Aw-Rascle-Zhang (GARZ) model for traffic flow. We prove the convergence to weak solutions of the corresponding macroscopic equations deriving $L ∞$ and BV estimates. We also provide numerical simulations illustrating the micro-macro convergence and we investigate numerically the non-local to local limit for both the microscopic and macroscopic models

Nuclear spin ratios of deuterated ammonia in prestellar cores. LAsMA observations of H-MM1 and Oph D

We determine the ortho/para ratios of NH2D and NHD2 in two dense, starless cores, where their formation is supposed to be dominated by gas-phase reactions, which, in turn, is predicted to result in deviations from the statistical spin ratios. The Large APEX sub-Millimeter Array (LAsMA) multibeam receiver of the Atacama Pathfinder EXperiment (APEX) telescope was used to observe the prestellar cores H-MM1 and Oph D in Ophiuchus in the ground-state lines of ortho and para NH2D and NHD2. The fractional abundances of these molecules were derived employing 3D radiative transfer modelling, using different assumptions about the abundance profiles as functions of density. We also ran gas-grain chemistry models with different scenarios concerning proton or deuteron exchanges and chemical desorption from grains to find out if one of these models can reproduce the observed spin ratios. The observationally deduced ortho/para ratios of NH2D and NHD2 are in both cores within 10% of their statistical values 3 and 2, respectively, and taking 3-sigma limits, deviations from these of about 20% are allowed. Of the chemistry models tested here, the model that assumes proton hop (as opposed to full scrambling) in reactions contributing to ammonia formation, and a constant efficiency of chemical desorption, comes nearest to the observed abundances and spin ratios. The nuclear spin ratios derived here are in contrast with spin-state chemistry models that assume full scrambling in proton donation and hydrogen abstraction reactions leading to deuterated ammonia. The efficiency of chemical desorption influences strongly the predicted abundances of NH3, NH2D, and NHD2, but has a lesser effect on their ortho/para ratios. For these the proton exchange scenario in the gas is decisive. We suggest that this is because of rapid re-processing of ammonia and related cations by gas-phase ion-molecule reactions.Comment: accepted for publication in Astronomy & Astrophysic

Cyanide-modified Pt(111) : structure, stability and hydrogen adsorption

A.C. acknowledges the support of the DGI (Spanish Ministry of Science and Innovation) through Project CTQ2009-07017. W.S. acknowledges financial support by the Deutsche Forschungsgemeinschaft under Schm 344/40-1, Schm 344/34-1.2 and FOR 1376. W.S. and P.Q. thank DFG-CONICET International Cooperation and CONICET for continued support. E.P.M.L. and M.Z.-M. wish to acknowledge CONICET PIP: 112-200801-000983, Secyt UNC, Program BID (PICT 2006N 946), and PME: 2006-01581 for financial support. P.Q. acknowledges PICT 0737-2008. A generous grant of computing time from the Baden-Wuerttemberg grid is gratefully acknowledged. M.E.-E. acknowledges an FPI fellowship from the Spanish Ministry of Science and Innovation and an accommodation grant at the Residencia de Estudiantes from the Madrid City Council.Peer reviewedPostprin

A non-local traffic flow model for 1-to-1 junctions

International audienceWe present a model for a class of non-local conservation laws arising in traffic flow modeling at road junctions. Instead of a single velocity function for the whole road, we consider two different road segments, which may differ for their speed law and number of lanes (hence their maximal vehicle density). We use an upwind type numerical scheme to construct a sequence of approximate solutions and we provide uniform L∞ and total variation estimates. In particular, the solutions of the proposed model stay positive and below the maximum density of each road segment. Using a Lax-Wendroff type argument and the doubling of variables technique, we prove the well-posedness of the proposed model. Finally, some numerical simulations are provided and compared with the corresponding (discontinuous) local model

Marked Changes in Gut Microbiota in Cardio-Surgical Intensive Care Patients:A Longitudinal Cohort Study

Background: Virtually no studies on the dynamics of the intestinal microbiota in patients admitted to the intensive care unit (ICU) are published, despite the increasingly recognized important role of microbiota on human physiology. Critical care patients undergo treatments that are known to influence the microbiota. However, dynamics and extent of such changes are not yet fully understood. To address this topic, we analyzed the microbiota before, during and after planned major cardio surgery that, for the first time, allowed us to follow the microbial dynamics of critical care patients. In this prospective, observational, longitudinal, single center study, we analyzed the fecal microbiota using 16S rRNA gene sequencing. Results: Samples of 97 patients admitted between April 2015 and November 2016 were included. In 32 patients, data of all three time points (before, during and after admission) were available for analysis. We found a large intra-individual variation in composition of gut microbiota. During admission, a significant change in microbial composition occurred in most patients, with a significant increase in pathobionts combined with a decrease in strictly anaerobic gut bacteria, typically beneficial for health. A lower bacterial diversity during admission was associated with longer hospitalization. In most patients analyzed at all three time points, the change in microbiota during hospital stay reverted to the original composition post-discharge. Conclusions: Our study shows that, even with a short ICU stay, patients present a significant change in microbial composition shortly after admission. The unique longitudinal setup of this study displayed a restoration of the microbiota in most patients to baseline composition post-discharge, which demonstrated its great restorative capacity. A relative decrease in benign or even beneficial bacteria and increase of pathobionts shifts the microbial balance in the gut, which could have clinical relevance. In future studies, the microbiota of ICU patients should be considered a good target for optimisation

Coastal Wetland Restoration through the lens of Odum\u27s theory of ecosystem development

Advancing ecological restoration assessments requires a more detailed consideration of species interactions and ecosystem processes. Most restoration projects rely on a few metrics not always directly linked with ecological theory. Here, we used Odum\u27s theory of ecosystem development to assess and compare the ecosystem structure and services of created marshes (4–6 years old) with preexisting, reference marshes in a brackish water region of the Mississippi River Delta. We built ecosystem models for created and reference marshes that integrated large datasets of stomach contents, stable isotopes, and taxa abundances. Despite strong resemblance in community structure, created marshes were at an earlier succession stage compared to the reference marshes, having lower biomass (including exploited species), higher biomass turnover and production, less dependence on detritus, lower material cycling, and less energy flowing through specialist pathways. Although preserving preexisting marshes should be a priority, created marshes may still be an important tool for the restoration of coastal areas and their ecosystem services. In addition, our results show that comparisons of species biodiversity alone may fail to capture essential differences in ecosystem processes between habitats, which reinforces the importance of ecosystem modeling approaches to assess restoration projects

Molecular Characterisation of Vancomycin-Resistant Enterococcus faecium Isolates Belonging to the Lineage ST117/CT24 Causing Hospital Outbreaks

Background: Vancomycin-resistant Enterococcus faecium (VREfm) is a successful nosocomial pathogen. The current molecular method recommended in the Netherlands for VREfm typing is based on core genome Multilocus sequence typing (cgMLST), however, the rapid emergence of specific VREfm lineages challenges distinguishing outbreak isolates solely based on their core genome. Here, we explored if a detailed molecular characterisation of mobile genetic elements (MGEs) and accessory genes could support and expand the current molecular typing of VREfm isolates sharing the same genetic background, enhancing the discriminatory power of the analysis. Materials/Methods: The genomes of 39 VREfm and three vancomycin-susceptible E. faecium (VSEfm) isolates belonging to ST117/CT24, as assessed by cgMLST, were retrospectively analysed. The isolates were collected from patients and environmental samples from 2011 to 2017, and their genomes were analysed using short-read sequencing. Pangenome analysis was performed on de novo assemblies, which were also screened for known predicted virulence factors, antimicrobial resistance genes, bacteriocins, and prophages. Two representative isolates were also sequenced using long-read sequencing, which allowed a detailed analysis of their plasmid content. Results: The cgMLST analysis showed that the isolates were closely related, with a minimal allelic difference of 10 between each cluster's closest related isolates. The vanB-carrying transposon Tn1549 was present in all VREfm isolates. However, in our data, we observed independent acquisitions of this transposon. The pangenome analysis revealed differences in the accessory genes related to prophages and bacteriocins content, whilst a similar profile was observed for known predicted virulence and resistance genes. Conclusion: In the case of closely related isolates sharing a similar genetic background, a detailed analysis of MGEs and the integration point of the vanB-carrying transposon allow to increase the discriminatory power compared to the use of cgMLST alone. Thus, enabling the identification of epidemiological links amongst hospitalised patients

Long-read sequencing-based in silico phage typing of vancomycin-resistant Enterococcus faecium

Abstract Background Vancomycin-resistant enterococci (VRE) are successful nosocomial pathogens able to cause hospital outbreaks. In the Netherlands, core-genome MLST (cgMLST) based on short-read sequencing is often used for molecular typing. Long-read sequencing is more rapid and provides useful information about the genome’s structural composition but lacks the precision required for SNP-based typing and cgMLST. Here we compared prophages among 50 complete E. faecium genomes belonging to different lineages to explore whether a phage signature would be usable for typing and identifying an outbreak caused by VRE. As a proof of principle, we investigated if long-read sequencing data would allow for identifying phage signatures and thereby outbreak-related isolates. Results Analysis of complete genome sequences of publicly available isolates showed variation in phage content among different lineages defined by MLST. We identified phage present in multiple STs as well as phages uniquely detected within a single lineage. Next, in silico phage typing was applied to twelve MinION sequenced isolates belonging to two different genetic backgrounds, namely ST117/CT24 and ST80/CT16. Genomic comparisons of the long-read-based assemblies allowed us to correctly identify isolates of the same complex type based on global genome architecture and specific phage signature similarity. Conclusions For rapid identification of related VRE isolates, phage content analysis in long-read sequencing data is possible. This allows software development for real-time typing analysis of long-read sequencing data, which will generate results within several hours. Future studies are required to assess the discriminatory power of this method in the investigation of ongoing outbreaks over a longer time period