1,348 research outputs found

    ¿El principio del fin de las relaciones colombo-venezolanas?

    Get PDF
    Reseña del siguiente libro:PASTRANA B., Eduardo, Carsten Wieland y Juan C. Vargas (2008). Vecindario agitado. Colombia y Venezuela: entre la hermandad y la conflictividad. Bogotá: Pontificia Universidad Javeriana, Facultad de Ciencias Políticas y Relaciones Internacionales, 272 páginas.

    High PM10 concentrations in the city of Buenos Aires and their relationship with meteorological conditions

    Get PDF
    In this work, the first long-term (eight years) record of hourly concentrations of carbon monoxide (CO), nitrogen dioxide (NO2) and particulate matter with diameter less than 10 μm (PM10) from three sites in the city of Buenos Aires is analysed. Considering the short-term guidelines suggested by the WHO, the daily mean PM10 concentrations present a relatively large number of exceedances at the three sites. Different statistical techniques are combined to study the relationship between these relatively high PM10 concentrations and relevant surface meteorological variables. For all pollutants and sites, wind speed shows the largest differences between the lowest and highest concentration quartiles. To further explore its role on daily mean PM10 concentration, a k-means algorithm is applied, grouping days with similar surface 1h-wind sequences. Five wind sequence clusters are found, presenting distinctive air quality data features. Two clusters (1 and 2) show that PM10 exceedances occurring with winds entering the city from the river represent between 10 and 21% of total events at the three sites. The frequency of exceedance under these conditions decreases with the distance to the coast. For cluster 1, the hourly PM10 concentration profile and its associated daily wind sequence suggest an important contribution to exceedance events from the city's southernmost power plant. Two clusters (3 and 4), exhibiting continental winds, account for 49–59% of the exceedances and co-occur with relatively drier air conditions. The correlation between CO and PM10 for days belonging to cluster 3 supports the hypothesis of a potential remote or distributed source contribution with SW winds. For cluster 4, differences among sites in the number of events under NNW winds suggest an important contribution from the city's widest avenue to the PM10 levels at the most coastal site. A large contribution coming from urban sources is also indicated for these winds. Finally, cluster 5, exhibiting low wind speed sequences, accounts for 23–33% of the exceedances at the three sites. The average PM10 concentration increases with persistence of this cluster, which could be a driver for exceedances. These results contribute to show the importance of simple methods such as clustering analysis to obtain insights into air quality features such as exceedances and their potential drivers. They also suggest that further efforts in monitoring, modelling and emission estimates may help to better understand local, urban and regional source contributions to these events in the city of Buenos Aires.Fil: Pineda Rojas, Andrea Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; ArgentinaFil: Borge, Rafael. Universidad Politécnica de Madrid; EspañaFil: Mazzeo, Nicolás A.. Universidad Tecnológica Nacional. Facultad Regional Avellaneda; ArgentinaFil: Saurral, Ramiro Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; ArgentinaFil: Matarazzo, Bruno Nicolas. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Cordero, Jose M.. Universidad Politécnica de Madrid; EspañaFil: Kropff, Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin

    Crecimiento de Baccharis macrantha y Viburnum triphyllum, dos especies nativas útiles en restauración ecológica, plantadas en un pastizal andino (Boyacá, Colombia)

    Get PDF
    We evaluated the effect of the application of nutrients on the growth of Baccharis macrantha and Viburnum triphyllum, which were planted in a pasture located on the edge of an oak forest in Arcabuco (Boyacá, Colombia). The following treatments were established in plots: B. macrantha with nutrients, B. macrantha without nutrients, V. triphyllum with nutrients, and V. triphyllum without nutrients, each one with three repetitions. The phytosanitary condition, greatest and least diameter of the plant canopy, and height were measured for each planted individual. Analysis of planted species survival using the Kaplan-Meier method was performed and rates of relative growth (RGR) of height and coverage were calculated for all individuals, with which ANOVAs were performed to assess differences between treatments. The probability of survival of planted species decreased greatly over time. Significant differences between treatments were found for height and cover. According to field observation and statistical analysis, the application of nutrients considerably improved the growth in height and cover of B. macrantha, a result useful for the implementation of ecological restoration activities in pastures.Se evaluó el efecto de la aplicación de nutrientes sobre el crecimiento de Baccharis macrantha y Viburnum triphyllum, plantadas en un pastizal ubicado en el borde de un bosque de roble en Arcabuco (Boyacá, Colombia). Los tratamientos establecidos en parcelas fueron: B. macrantha con nutrientes, B. macrantha sin nutrientes, V. triphyllum con nutrientes y V. triphyllum sin nutrientes, cada uno con tres repeticiones. Se registró el estado fitosanitario, diámetro mayor y menor de la copa y altura de todos los individuos plantados. Se realizó el análisis de supervivencia de las especies plantadas por el método de Kaplan-Meier y se calcularon las tasas de crecimiento relativo (TCR) de altura y cobertura para todos los individuos, con las cuales se realizaron ANOVAS para evaluar diferencias entre tratamientos. La probabilidad de supervivencia de las especies plantadas disminuyó en gran medida a través del tiempo. Se encontraron diferencias significativas para el factor especie en la variable altura y diferencias significativas para la interacción especie-nutriente para la cobertura. De acuerdo a los análisis estadísticos y observación en campo la aplicación de nutrientes benefició considerablemente el crecimiento en altura y cobertura de la especie B. macrantha, resultado útil para la implementación de actividades de restauración ecológica en pastizales

    Discovery, Semisynthesis, Antiparasitic and Cytotoxic Evaluation of 14-Membered Resorcylic Acid Lactones and Their Derivatives

    Get PDF
    Ten antifouling 14-membered resorcylic acid lactones 1–10 were isolated previously with low or trace natural abundance from the zoanthid-derived Cochliobolus lunatus fungus. Further optimization of fermentation conditions led to the isolation of two major natural compounds 7 and 8 with multi-gram quantities. By one or two steps, we semisynthesized the six trace natural compounds 1–6 and a series of derivatives 11–27 of compounds 7 and 8 with high yields (65–95%). Compounds 11–13 showed strong antiplasmodial activity against Plasmodium falciparum with IC50 values of 1.84, 8.36, and 6.95μM, respectively. Very importantly, 11 and 12 were non-toxic with very safety and high therapeutic indices (CC50/IC50>180), and thus representing potential promising leads for antiplasmodial drug discovery. Furthermore, 11 was the only compound showed obvious antileishmanial activity against Leishmania donovani with an IC50 value of 9.22μM. Compounds 11 and 12 showed the values of IC50 at 11.9 and 17.2μM against neglected Chagas’ disease causing Trypanosoma cruzi, respectivelyTen antifouling 14-membered resorcylic acid lactones 1–10 were isolated previously with low or trace natural abundance from the zoanthid-derived Cochliobolus lunatus fungus. Further optimization of fermentation conditions led to the isolation of two major natural compounds 7 and 8 with multi-gram quantities. By one or two steps, we semisynthesized the six trace natural compounds 1–6 and a series of derivatives 11–27 of compounds 7 and 8 with high yields (65–95%). Compounds 11–13 showed strong antiplasmodial activity against Plasmodium falciparum with IC50 values of 1.84, 8.36, and 6.95μM, respectively. Very importantly, 11 and 12 were non-toxic with very safety and high therapeutic indices (CC50/IC50>180), and thus representing potential promising leads for antiplasmodial drug discovery. Furthermore, 11 was the only compound showed obvious antileishmanial activity against Leishmania donovani with an IC50 value of 9.22μM. Compounds 11 and 12 showed the values of IC50 at 11.9 and 17.2μM against neglected Chagas’ disease causing Trypanosoma cruzi, respectivel

    Discovery, Semisynthesis, Antiparasitic and Cytotoxic Evaluation of 14-Membered Resorcylic Acid Lactones and Their Derivatives

    Get PDF
    Ten antifouling 14-membered resorcylic acid lactones 1–10 were isolated previously with low or trace natural abundance from the zoanthid-derived Cochliobolus lunatus fungus. Further optimization of fermentation conditions led to the isolation of two major natural compounds 7 and 8 with multi-gram quantities. By one or two steps, we semisynthesized the six trace natural compounds 1–6 and a series of derivatives 11–27 of compounds 7 and 8 with high yields (65–95%). Compounds 11–13 showed strong antiplasmodial activity against Plasmodium falciparum with IC50 values of 1.84, 8.36, and 6.95 μM, respectively. Very importantly, 11 and 12 were non-toxic with very safety and high therapeutic indices (CC50/IC50 > 180), and thus representing potential promising leads for antiplasmodial drug discovery. Furthermore, 11 was the only compound showed obvious antileishmanial activity against Leishmania donovani with an IC50 value of 9.22 μM. Compounds 11 and 12 showed the values of IC50 at 11.9 and 17.2 μM against neglected Chagas’ disease causing Trypanosoma cruzi, respectively.Ten antifouling 14-membered resorcylic acid lactones 1–10 were isolated previously with low or trace natural abundance from the zoanthid-derived Cochliobolus lunatus fungus. Further optimization of fermentation conditions led to the isolation of two major natural compounds 7 and 8 with multi-gram quantities. By one or two steps, we semisynthesized the six trace natural compounds 1–6 and a series of derivatives 11–27 of compounds 7 and 8 with high yields (65–95%). Compounds 11–13 showed strong antiplasmodial activity against Plasmodium falciparum with IC50 values of 1.84, 8.36, and 6.95 μM, respectively. Very importantly, 11 and 12 were non-toxic with very safety and high therapeutic indices (CC50/IC50 > 180), and thus representing potential promising leads for antiplasmodial drug discovery. Furthermore, 11 was the only compound showed obvious antileishmanial activity against Leishmania donovani with an IC50 value of 9.22 μM. Compounds 11 and 12 showed the values of IC50 at 11.9 and 17.2 μM against neglected Chagas’ disease causing Trypanosoma cruzi, respectively

    Coibacins A D, Antileishmanial Marine Cyanobacterial Polyketides with Intriguing Biosynthetic Origins

    Get PDF
    Four unsaturated polyketide lactone derivatives, coibacins A-D, were isolated from a Panamanian marine cyanobacterium, cf. Oscillatoria sp. The two different types of termini observed in these co-occurring metabolites, either a methyl cyclopropyl ring as seen in curacin A or a methyl vinyl chloride similar to that observed in the jamaicamides, suggest an intriguing flexibility in the “beta branch” forming biosynthetic process. The coibacins possess selective antileishmanial activity as well as potent anti-inflammatory activity.Four unsaturated polyketide lactone derivatives, coibacins A-D, were isolated from a Panamanian marine cyanobacterium, cf. Oscillatoria sp. The two different types of termini observed in these co-occurring metabolites, either a methyl cyclopropyl ring as seen in curacin A or a methyl vinyl chloride similar to that observed in the jamaicamides, suggest an intriguing flexibility in the “beta branch” forming biosynthetic process. The coibacins possess selective antileishmanial activity as well as potent anti-inflammatory activity

    Multicomponent analysis of the tumour microenvironment reveals low CD8 T cell number, low stromal caveolin-1 and high tenascin-C and their combination as significant prognostic markers in non-small cell lung cancer

    Get PDF
    The complex interplay of the tumour microenvironment (TME) and its role in disease progression and response to therapy is poorly understood. The majority of studies to date focus on individual components or molecules within the TME and so lack the power correlative analysis. Here we have performed a multi-parameter analysis of the TME in 62 resectable non-small cell lung cancer (NSCLC) specimens detailing number and location of immune infiltrate, assessing markers of cancer-associated fibroblasts, caveolin-1 and tenascin-C, and correlating with clinicopathological details, as well as markers of disease progression such as epithelial-to-mesenchymal transition (EMT). The influence of individual parameters on overall survival was determined in univariate and multivariate analysis and the combination of risk factors and interplay between components analysed. Low numbers of CD8 T cells, low stromal levels of caveolin-1 or high levels of tenascin-C were significant prognostic markers of decreased overall survival in both univariate and multivariate analysis. Patients with two or more risk factors had dramatically reduced overall survival and those with all three a median survival of just 7.5 months. In addition, low levels of tumour E-cadherin correlated with reduced immune infiltrate into the tumour nests, possibly linking EMT to the avoidance of CD8 T cell control. The multicomponent approach has allowed identification of the dominant influences on overall survival, and exploration of the interplay between different components of the TME in NSCLC

    Plaguicides COP, avaluació de l’exposició de la població

    Get PDF
    Contaminants orgànics persistents (COP); Plaguicides; Seguretat alimentàriaContaminantes orgánicos persistentes (COP); Plaguicidas; Seguridad alimentariaPersistent Organic Pollutants (POP); Pesticides; Food safetyAquest informe és fruit del treball col·laboratiu entre la Universitat de Barcelona, l’Agència de Salut Pública de Barcelona i l’Agència Catalana de Seguretat Alimentària per estimar l’exposició de la població de Catalunya als plaguicides que, per la seva naturalesa química, tenen la consideració de contaminants orgànics persistents.Este informe es fruto del trabajo colaborativo entre la Universidad de Barcelona, la Agencia de Salud Pública de Barcelona y la Agencia Catalana de Seguridad Alimentaria para estimar la exposición de la población de Cataluña a los plaguicidas que, por su naturaleza química, tienen la consideración de contaminantes orgánicos persistentes.This report is the result of the collaborative work between the University of Barcelona, the Public Health Agency of Barcelona and the Catalan Food Safety Agency to estimate the exposure of the population of Catalonia to pesticides that, due to their chemical nature, have the consideration of persistent organic pollutants

    Loss of α2-6 sialylation promotes the transformation of synovial fibroblasts into a pro-inflammatory phenotype in arthritis

    Get PDF
    In healthy joints, synovial fibroblasts (SFs) provide the microenvironment required to mediate homeostasis, but these cells adopt a pathological function in rheumatoid arthritis (RA). Carbohydrates (glycans) on cell surfaces are fundamental regulators of the interactions between stromal and immune cells, but little is known about the role of the SF glycome in joint inflammation. Here we study stromal guided pathophysiology by mapping SFs glycosylation pathways. Combining transcriptomic and glycomic analysis, we show that transformation of fibroblasts into pro-inflammatory cells is associated with glycan remodeling, a process that involves TNF-dependent inhibition of the glycosyltransferase ST6Gal1 and α2-6 sialylation. SF sialylation correlates with distinct functional subsets in murine experimental arthritis and remission stages in human RA. We propose that pro-inflammatory cytokines remodel the SF-glycome, converting the synovium into an under-sialylated and highly pro-inflammatory microenvironment. These results highlight the importance of glycosylation in stromal immunology and joint inflammation

    Differential effect of vascularity between long- and short-term survivors with IDH1/2 wild-type glioblastoma

    Full text link
    [EN] Introduction: IDH1/2 wt glioblastoma (GB) represents the most lethal tumour of the central nervous system. Tumour vascularity is associated with overall survival (OS), and the clinical relevance of vascular markers, such as rCBV, has already been validated. Nevertheless, molecular and clinical factors may have different influences on the beneficial effect of a favourable vascular signature. Purpose: To evaluate the association between the rCBV and OS of IDH1/2 wt GB patients for long-term survivors (LTSs) and short-term survivors (STSs). Given that initial high rCBV may affect the patient's OS in follow-up stages, we will assess whether a moderate vascularity is beneficial for OS in both groups of patients. Materials and methods: Ninety-nine IDH1/2 wt GB patients were divided into LTSs (OS >= 400 days) and STSs (OS < 400 days). Mann-Whitney and Fisher, uni- and multiparametric Cox, Aalen's additive regression and Kaplan-Meier tests were carried out. Tumour vascularity was represented by the mean rCBV of the high angiogenic tumour (HAT) habitat computed through the haemodynamic tissue signature methodology (available on the ONCOhabitats platform). Results: For LTSs, we found a significant association between a moderate value of rCBV(mean) and higher OS (uni- and multiparametric Cox and Aalen's regression) (p = 0.0140, HR = 1.19; p = 0.0085, HR = 1.22) and significant stratification capability (p = 0.0343). For the STS group, no association between rCBV(mean) and survival was observed. Moreover, no significant differences (p > 0.05) in gender, age, resection status, chemoradiation, or MGMT methylation were observed between LTSs and STSs. Conclusion: We have found different prognostic and stratification effects of the vascular marker for the LTS and STS groups. We propose the use of rCBV(mean) at HAT as a vascular marker clinically relevant for LTSs with IDH1/2 wt GB and maybe as a potential target for randomized clinical trials focused on this group of patients.DPI2016-80054-R (Programa Estatal de Promocion del Talento y su Empleabilidad en I +D+i).; European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 844646; H2020-SC1-BHC-2018-2020 (No. 825750); MTS4up project (National Plan for Scientific and Technical Research and Innovation 2013-2016, No. DPI2016-80054-R); European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie, Grant/Award Number: 844646; Research Council of Norway, Grant/Award Number: 261984; South-Eastern Norway Regional Health Authority, Grant/Award Number: 2017073; European Research Council (ERC) under the European Union's Horizon 2020, Grant/Award Number: 758657Álvarez-Torres, MDM.; Fuster García, E.; Reynes, G.; Juan-Albarracín, J.; Chelebian-Kocharyan, EA.; Oleaga, L.; Pineda, J.... (2021). Differential effect of vascularity between long- and short-term survivors with IDH1/2 wild-type glioblastoma. NMR in Biomedicine. 34(4):1-11. https://doi.org/10.1002/nbm.446211134
    corecore