149 research outputs found

    Emisión de CO2 y pérdida de biomasa, asociada a la ocurrencia de incendios forestales en la Región del Biobío, Chile: Una aproximación desde los Servicios Ecosistémicos (SE)

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    Fire is a phenomenon inherent to natural forests, but the management model for forest plantations may increase its frequencyand intensity, since it is an important disturbing agent which generates changes in the dynamic that governs the operationof ecosystems and the loss or reduction of many ecosystem services. The main objective of this work is to review theproblem of forest fires in Chile with special reference to the Biobío Region, quantifying the loss of some of the ecosystemservices caused by this phenomenon. The results show that on average during the last ten years, the Biobío Region hasbecome the largest national area affected by fires (179.912 ha), confirming that these events are highly correlated withforest development (r = 0.5; P < 0.05), amounting to 50.7 % of the national total. Due to limited knowledge on the effectsof fires at the local level, results are discussed in the context of direct losses of ecosystem services, particularly the effectsin the atmosphere (CO2 emissions and biomass), stressing the importance of the conservation of native forests as absorptionsystems for the effects of fire.El fuego es un fenómeno consustancial con los bosques naturales, pero el modelo de gestión y manejo de las plantacionesforestales puede incrementar su frecuencia e intensidad, convirtiéndose en un importante agente perturbador que generacambios en la dinámica ecológica que rige el funcionamiento de los ecosistemas y la pérdida o disminución de muchosservicios ecosistémicos. El principal objetivo de este trabajo es revisar la problemática de los incendios forestales enChile con especial referencia a la Región del Biobío, cuantificando la pérdida de algunos de los servicios ecosistémicosprovocada por este fenómeno. Los resultados muestran que en promedio durante los últimos diez años, la Región delBiobío ha alcanzado la mayor superficie nacional afectada por incendios (179.912 ha), constatando que dichos eventosestán altamente correlacionados con el desarrollo forestal alcanzado en la región (r = 0.5; P < 0,05), que equivale al 50,7%del nacional. Debido al escaso conocimiento de los efectos de los incendios a nivel local, los resultados se discuten en elcontexto de las pérdidas directas de los servicios ecosistémicos, particularmente los efectos en la atmósfera (emisiones deCO2, destacando la importancia de la conservación de los bosques nativos como sistemas amortiguadores de los efectosdel fuego

    A reciclable bifuctional acid-base organocatalyst with ionic liquid character. The role of sites separation and spatial configuration on different condensation reaction

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    A series of bifunctional organic catalysts containing acid and basic sites with ionic liquid characteristics have been prepared and their catalytic activity and reaction coordinate for aldol and Knoevenagel condensations have been compared. While the only factor controlling catalyst activity for the Knoevenagel condensation was the distance between the acid and base sites, the spatial orientation of the organocatalyst is also key to achieve high activity and selectivity in the Claisen-Schmidt condensation. Mechanistic studies based on theoretical DFT calculations show that the acid-base bifunctional organocatalyst follows a mechanism inspired in natural aldolases for the synthesis of trans-chalcones, being able to produce a large variety of these compounds of industrial interest. The combination of the acid-base pairs within the proper geometry and the ionic liquid nature makes this catalyst active, selective and recyclable.We thank Consolider-Ingenio 2010 (project MULTICAT), Spanish MICINN (Project MAT2006-14274-C02-01), Generalitat Valenciana (Project PROMETEO/2008/130), and Fundacion Areces for financial support.Corma Canós, A.; Boronat Zaragoza, M.; Climent Olmedo, MJ.; Iborra Chornet, S.; Montón Molina, R.; Sabater Picot, MJ. (2011). A reciclable bifuctional acid-base organocatalyst with ionic liquid character. The role of sites separation and spatial configuration on different condensation reaction. Physical Chemistry Chemical Physics. 13(38):17255-17261. https://doi.org/10.1039/c1cp21986cS17255172611338Motokura, K., Tada, M., & Iwasawa, Y. (2008). Acid-Base Bifunctional Catalytic Surfaces for Nucleophilic Addition Reactions. Chemistry - An Asian Journal, 3(8-9), 1230-1236. doi:10.1002/asia.200800126Gröger, H. (2001). The Development of New Monometallic Bifunctional Catalysts with Lewis acidand Lewis Base Properties, and their Application in Asymmetric Cyanation Reactions. Chemistry - A European Journal, 7(24), 5246-5251. doi:10.1002/1521-3765(20011217)7:243.0.co;2-oKanai, M., Kato, N., Ichikawa, E., & Shibasaki, M. (2005). Recent progress in Lewis acid-Lewis base bifunctional asymmetric catalysis. Pure and Applied Chemistry, 77(12), 2047-2052. doi:10.1351/pac200577122047Shen, Y., Feng, X., Li, Y., Zhang, G., & Jiang, Y. (2003). A mild and efficient cyanosilylation of ketones catalyzed by a Lewis acid–Lewis base bifunctional catalyst. Tetrahedron, 59(30), 5667-5675. doi:10.1016/s0040-4020(03)00908-6Kanemasa, S., & Ito, K. (2004). Double Catalytic Activation with Chiral Lewis Acid and Amine Catalysts. European Journal of Organic Chemistry, 2004(23), 4741-4753. doi:10.1002/ejoc.200400277Ma, J.-A., & Cahard, D. (2004). Towards Perfect Catalytic Asymmetric Synthesis: Dual Activation of the Electrophile and the Nucleophile. Angewandte Chemie International Edition, 43(35), 4566-4583. doi:10.1002/anie.200300635Wang, Y., Li, H., Wang, Y.-Q., Liu, Y., Foxman, B. M., & Deng, L. (2007). Asymmetric Diels−Alder Reactions of 2-Pyrones with a Bifunctional Organic Catalyst. Journal of the American Chemical Society, 129(20), 6364-6365. doi:10.1021/ja070859hLin, Y.-M., Boucau, J., Li, Z., Casarotto, V., Lin, J., Nguyen, A. N., & Ehrmantraut, J. (2007). A Lewis Acid−Lewis Base Bifunctional Catalyst from a New Mixed Ligand. Organic Letters, 9(4), 567-570. doi:10.1021/ol0626903Corma, A., Ródenas, T., & Sabater, M. (2010). A Bifunctional Pd/MgO Solid Catalyst for the One-Pot Selective N-Monoalkylation of Amines with Alcohols. Chemistry - A European Journal, 16(1), 254-260. doi:10.1002/chem.200901501Ruiz, V. R., Corma, A., & Sabater, M. J. (2010). New route for the synthesis of benzimidazoles by a one-pot multistep process with mono and bifunctional solid catalysts. Tetrahedron, 66(3), 730-735. doi:10.1016/j.tet.2009.11.048Boronat, M., Climent, M. J., Corma, A., Iborra, S., Montón, R., & Sabater, M. J. (2010). Bifunctional Acid-Base Ionic Liquid Organocatalysts with a Controlled Distance Between Acid and Base Sites. Chemistry - A European Journal, 16(4), 1221-1231. doi:10.1002/chem.200901519Boronat, M., Concepción, P., Corma, A., Navarro, M. T., Renz, M., & Valencia, S. (2009). Reactivity in the confined spaces of zeolites: the interplay between spectroscopy and theory to develop structure–activity relationships for catalysis. Physical Chemistry Chemical Physics, 11(16), 2876. doi:10.1039/b821297jCorma, A., & Renz, M. (2007). A General Method for the Preparation of Ethers Using Water-Resistant Solid Lewis Acids. Angewandte Chemie International Edition, 46(1-2), 298-300. doi:10.1002/anie.200604018Boronat, M., Corma, A., Renz, M., & Viruela, P. M. (2006). Predicting the Activity of Single Isolated Lewis Acid Sites in Solid Catalysts. Chemistry - A European Journal, 12(27), 7067-7077. doi:10.1002/chem.200600478Climent, M. J., Corma, A., De Frutos, P., Iborra, S., Noy, M., Velty, A., & Concepción, P. (2010). Chemicals from biomass: Synthesis of glycerol carbonate by transesterification and carbonylation with urea with hydrotalcite catalysts. The role of acid–base pairs. Journal of Catalysis, 269(1), 140-149. doi:10.1016/j.jcat.2009.11.001Climent, M. J., Corma, A., Iborra, S., Mifsud, M., & Velty, A. (2010). New one-pot multistep process with multifunctional catalysts: decreasing the E factor in the synthesis of fine chemicals. Green Chem., 12(1), 99-107. doi:10.1039/b919660aCorma, A., Iborra, S., & Velty, A. (2007). Chemical Routes for the Transformation of Biomass into Chemicals. Chemical Reviews, 107(6), 2411-2502. doi:10.1021/cr050989dCliment, M. J., Corma, A., & Iborra, S. (2011). Heterogeneous Catalysts for the One-Pot Synthesis of Chemicals and Fine Chemicals. Chemical Reviews, 111(2), 1072-1133. doi:10.1021/cr1002084Koshland, D. E. (1958). Application of a Theory of Enzyme Specificity to Protein Synthesis. Proceedings of the National Academy of Sciences, 44(2), 98-104. doi:10.1073/pnas.44.2.98Bass, J. D., Solovyov, A., Pascall, A. J., & Katz, A. (2006). Acid−Base Bifunctional and Dielectric Outer-Sphere Effects in Heterogeneous Catalysis:  A Comparative Investigation of Model Primary Amine Catalysts. Journal of the American Chemical Society, 128(11), 3737-3747. doi:10.1021/ja057395cVasella, A., Davies, G. J., & Böhm, M. (2002). Glycosidase mechanisms. Current Opinion in Chemical Biology, 6(5), 619-629. doi:10.1016/s1367-5931(02)00380-0Drexler, M. (2003). The effect of solvents on the heterogeneous synthesis of flavanone over MgO. Journal of Catalysis, 214(1), 136-145. doi:10.1016/s0021-9517(02)00013-1Fuentes, A., Marinas, J. M., & Sinisterra, J. V. (1987). Catalyzed synthesis of chalcones under interfacial solid-liquid conditions with ultrasound. Tetrahedron Letters, 28(39), 4541-4544. doi:10.1016/s0040-4039(00)96558-4Climent, M. ., Corma, A., Iborra, S., & Velty, A. (2004). Activated hydrotalcites as catalysts for the synthesis of chalcones of pharmaceutical interest. Journal of Catalysis, 221(2), 474-482. doi:10.1016/j.jcat.2003.09.012Shen, J., Wang, H., Liu, H., Sun, Y., & Liu, Z. (2008). Brønsted acidic ionic liquids as dual catalyst and solvent for environmentally friendly synthesis of chalcone. Journal of Molecular Catalysis A: Chemical, 280(1-2), 24-28. doi:10.1016/j.molcata.2007.10.021Ballesteros, J. F., Sanz, M. J., Ubeda, A., Miranda, M. A., Iborra, S., Paya, M., & Alcaraz, M. J. (1995). Synthesis and Pharmacological Evaluation of 2’-Hydroxychalcones and Flavones as Inhibitors of Inflammatory Mediators Generation. Journal of Medicinal Chemistry, 38(14), 2794-2797. doi:10.1021/jm00014a032Yit, C. C., & Das, N. P. (1994). Cytotoxic effect of butein on human colon adenocarcinoma cell proliferation. Cancer Letters, 82(1), 65-72. doi:10.1016/0304-3835(94)90147-3Becke, A. D. (1993). Density‐functional thermochemistry. III. The role of exact exchange. The Journal of Chemical Physics, 98(7), 5648-5652. doi:10.1063/1.464913Perdew, J. P., & Wang, Y. (1992). Accurate and simple analytic representation of the electron-gas correlation energy. Physical Review B, 45(23), 13244-13249. doi:10.1103/physrevb.45.13244Dewar, M. J. S., & Thiel, W. (1977). Ground states of molecules. 39. MNDO results for molecules containing hydrogen, carbon, nitrogen, and oxygen. Journal of the American Chemical Society, 99(15), 4907-4917. doi:10.1021/ja00457a005Davis, L. P., Guidry, R. M., Williams, J. R., Dewar, M. J. S., & Rzepa, H. S. (1981). MNDO calculations for compounds containing aluminum and boron. Journal of Computational Chemistry, 2(4), 433-445. doi:10.1002/jcc.540020412Hill, H. A. O., Lobb, R. R., Sharp, S. L., Stokes, A. M., Harris, J. I., & Jack, R. S. (1976). Metal-replacement studies in Bacillus stearothermophilus aldolase and a comparison of the mechanisms of class I and class II aldolases. Biochemical Journal, 153(3), 551-560. doi:10.1042/bj153055

    Elucidating the Structure of the Cu-Alkaline Electrochemical Interface with the Laser-Induced Temperature Jump Method

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    A detailed description of the Cu–electrolyte interface is vital to understand the electrocatalytic properties of Cu surfaces. Herein, we combine cyclic voltammetry and the laser-induced temperature jump technique to describe the structure of the Cu(111) and Cu(100) | electrolyte interfaces in 0.1 M NaOH in a glass-free electrochemical cell. The laser-induced potential transients recorded at different potentials provided information of the surface charge distribution, which allowed us to calculate the potential of maximum entropy (pme), which can be considered as a good estimation of the potential of zero charge (pzc) of Cu(111) and Cu(100). We found that pzcCu(111) > pzcCu(100), following the same order as their respective work function values. Interestingly, the estimated pzc appears to be located at the onset potential of the OH* voltammetric feature for Cu(111) and Cu(100), which suggests that this feature shifts with the pzc of each crystallographic orientation. This is the first study that provides the experimental evidence of charge distribution at the Cu–solution interface under alkaline conditions.M.E.-E. gratefully acknowledges the Villum Foundation for the award of a Villum Young Investigator Grant (project number 19142). J.M.F. thanks the MCINN (FEDER) (Spain) project PID2019-105653GB-100

    Variación en asignación reproductiva temprana en ensayos multi-localidad de pino carrasco y pino negral

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    Life histories in Mediterranean pines are well known to be closely related to different fire and disturbance regimes. Variation in these factors is also reflected in reproductive strategies at the specific and intraspecific level. Specifically, the onset of reproduction is a crucial stage for any organism because it has profound implications on fitness. In this paper we focus on the intraspecific variation and plasticity in the threshold size for reproduction and reproductive allocation in two Mediterranean pines, assessed at the onset of reproduction, when trade-offs between reproduction and growth are expected to be greater. Replicated common garden provenance and progeny trials of Aleppo pine and Maritime pine were used to estimate genetic parameters for reproduction and vegetative growth, as well as variation in plasticity in reproductive strategies at the intraspecific level. In both species, high variation among populations was found for both threshold size for reproduction and for reproductive allocation. Reproductive allocation was also highly variable within populations and showed moderate to high values of heritability and high coefficients of additive genetic variation. These results indicate a high genetic control of these reproductive traits, while high additive genetic variation is maintained, allowing to face selective pressures. Moreover, reproductive strategies although plastic, showed low genotype × environment interaction, and intraspecific variation was highly consistent across trial sites both at the population and the family levels. The former data confirm the strong genetic control of reproductive traits in these species. Finally, the fact that Aleppo pine starts its reproductive phase as female while Maritime pine can start reproducing either as male or female deserves further attention.Las estrategias de historia vital en pinos mediterráneos están estrechamente ligadas a diversos regímenes de incendios y perturbaciones. A su vez, la variabilidad de esos factores también se ve reflejada en las estrategias reproductivas a niveles inter e intraespecíficos. Concretamente, el comienzo de la reproducción es una etapa crucial para cualquier organismo debido a su profunda influencia en su adaptación al medio. Este trabajo se enfoca en el estudio de la variabilidad intraespecífica y la plasticidad en el tamaño umbral de reproducción y la asignación reproductiva en dos pinos mediterráneos. El estudio se realizó durante el comienzo de la fase reproductiva, momento en que se estima que la compensación entre reproducción y crecimiento es de mayor importancia. Se utilizaron ensayos multi-sitio de procedencias y progenies de pino carrasco y pino negral para estimar los parámetros genéticos de caracteres reproductivos y de crecimiento vegetativo, así como para conocer la variabilidad en la plasticidad de las estrategias reproductivas a nivel intraespecífico. En ambas especies se halló una alta variabilidad entre poblaciones para el tamaño umbral de reproducción y para la asignación reproductiva. La asignación reproductiva también fue altamente variable dentro de poblaciones y mostró valores de heredabilidad de moderados a altos y altos coeficientes de varianza genética aditiva. Estos resultados indican un alto control genético de los rasgos reproductivos, mientras se mantiene una alta varianza genética, permitiendo afrontar futuras presiones selectivas. Además, a pesar de la existencia de plasticidad en las estrategias reproductivas, éstas mostraron una baja interacción genotipo × ambiente, y la variación intraespecífica fue acorde en los diferentes lugares de ensayo tanto a nivel poblacional como familiar. Los datos anteriores confirman el alto control genético de los rasgos reproductivos en estas especies. Finalmente, el hecho de que el pino carrasco comience su fase reproductora como hembra mientras que el pino negral pueda comenzar su reproducción bien como macho o bien como hembra, merece una atención más detallada.This research was developed as part of projects AT07-002 and INIA-RTA07-100 of INIA and PSS-310000-2008-4 of the Spanish Ministry of Science and Innovation. Genetic trials reported in this paper form part of Genfored network of forest genetic trials in Spain, implemented mainly through project CC03-048 (DGB-INIA agreement). PMER and PCAV trials were installed as part of project TREESNIPS (QLK3-CT2002-01973). PRIA and PREB trials were established under the Genetic Breeding Program of Galicia by the Centro de Investigación Forestal de Lourizán. Luis Santos is supported by the Spanish Ministry of Education via a doctoral grant (FPU AP-2007-03302

    Determinants of highly active antiretroviral therapy duration in HIV-1-infected children and adolescents in Madrid, Spain, from 1996 to 2012

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    Objectives: To investigate the duration of sequential HAART regimens and predictors of first-line regimen discontinuation among HIV-1 vertically infected children and adolescents. Design: Multicentre survey of antiretroviral-naı¨ve patients enrolled in the HIV-Paediatric Cohor,t CoRISpeS-Madrid Cohort, Spain. Methods: Patients with a follow-up of $1 month spent on HAART, with available baseline CD4 count and HIV-viral load (VL) were included. Time spent on sequential HAART regimens was estimated and multivariable regression was used to identify predictors of time to first-line regimen discontinuation. Results: 104 patients were followed for a median 8 years after starting HAART among 1996–2012; baseline %CD4 was 21.5 (12.3–34.0)and viral load was 5.1 (4.6–5.6) log10 copies/mL. Patients received a mean of 1.9 regimens. Median time on firstline HAART (n = 104) was 64.5 months; second HAART (n = 56) 69.8 months; and third HAART (n = 21) 66.5 months. Eleven (11%) patients were lost to follow-up while on first-line HAART and 54% discontinued (cumulative incidence of 16% and 38% by 1 and 3-year, respectively). The main predictor of first-line regimen discontinuation was suboptimal adherence to antiretrovirals (AHR: 2.60; 95% CI: 1.44–4.70). Conclusions: Adherence to therapy was the main determinant of the duration of the first-line HAART regimen in children. It is important to identify patients at high risk for non-adherence, such as very young children and adolescents, in provide special care and support to those patients.This work was supported by grants provided by the Fondo de Investigación de Sanidad en España (FIS) [grant numbers PI11-00888, PS09/02029, and PI13/02016], Red Española de Investigación en SIDA (RIS) [grant numbers RETIC RD06/0006/0035 RD12-0017-0037; RD06/0006/0021, RD12/0017/0029 and RD09/0076/00103], “Fundación para la Investigación y la Prevención del Sida en España” (FIPSE), Comunidad de Madrid [grant numbers, S-2010/BMD-2351, S-2010/BMD-2332], PENTA and Fundación Eugenio Rodríguez Pascual and grants PTDC/SAU-FAR/115290/2009 and PTDC/SAU-EPI/122400/2010 from Fundação para a Ciência e Tecnologia (FCT) (http://www.fct.pt), Portugal. Claudia Palladino is supported by the Portuguese Fundação para a Ciência e Tecnologia (FCT) (SFRH/BPD/77448/2011). Verónica Briz is supported by the Spanish Fondo de Investigación Sanitaria (Sara Borrell CD09/00433)

    Heteropolycompounds as catalysts for biomass product transformations

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    [EN] In the present review we show a variety of biomass product transformations through catalysis by both bulk and supported heteropolycompounds. The biomass sources considered include carbohydrates, oils and fats, and terpenes as main starting material groups. The products obtained and their applications are presented.We thank CONICET (PIP 003), Agencia Nacional de Promocion Cientifica y Tecnologica (Argentina) (PICT 0406), and Universidad Nacional de La Plata for financial support. GPR and HJT are members of CONICET. MJC and SI thank to Spanish Government-MINECO through Consolider Ingenio 2010-Multicat project for financial support.Sanchez, LM.; Thomas, HJ.; Climent Olmedo, MJ.; Romanelli, GP.; Iborra Chornet, S. (2016). Heteropolycompounds as catalysts for biomass product transformations. Catalysis Reviews: Science and Engineering. 58(4):497-586. doi:10.1080/01614940.2016.1248721S49758658

    Chemoselective Reductive Heterocyclization by Controlling the Binomial Architecture of Metal Particles and Acid−Base Properties of the Support

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    2,1-Benzisoxazoles have been selectively synthesized through reductive heterocyclization of 2-nitroacylarenes using Pt-supported nanoparticles. The reaction involves a cascade process in which the first step is the reduction of the nitro group into hydroxylamine followed by heterocyclization through the nucleophilic attack of the hydroxylamine group to the carbonyl of the acyl group and further dehydration. The reaction was performed on Pt/C, Pt/TiO2, and Pt/MgO using hydrogen as the reducing agent under mild reaction conditions. The results showed that Pt/MgO was the most active and selective catalyst. The study of the influence of the crystal size of the metal on the activity and selectivity, combined with the reaction mechanism examined by in situ Fourier transform infrared spectroscopy of the adsorbed reactant, showed that the maximum activity and selectivity to the target compound can be achieved by controlling the architecture of metal particles and acid–base properties of the support. The effect of temperature on selectivity, the stability of the Pt/MgO catalyst, and the scope of the reaction have been studied. Finally, reductive heterocyclization using different metals (Pd and Au) supported on MgO has also been performed.Centro de Investigación y Desarrollo en Ciencias Aplicada

    On the behavior of CTAB/CTAOH adlayers on gold single crystal surfaces

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    The behavior of adsorbed CTAB and CTAOH on gold single crystal electrodes has been studied in solutions with different pH values. For the different single crystal electrodes, the adsorbed adlayer formed by CTA+ cations is in contact with the surface, when the electrode charge is negative. As the surface charge becomes positive, the adlayer detaches from the surface and water molecules permeate through it, giving rise to characteristic peaks in the voltammogram. Charge and laser induced jump temperature measurements show that the composition of the adlayer contains not only the CTA+ cations but also anions, which are required to stabilize the adlayer. In alkaline solutions, the higher solubility of CTAB/CTAOH in alkaline solutions leads to the partial desorption of the adlayer when these species are not present in the solution. When CTAB or CTAOH are dissolved in the alkaline cell solution, the adlayer is strongly bonded to the surface in the whole potential window due to the negative charge of the surface.Financial support from Ministerio de Ciencia e Innovación (Project PID2019-105653GB-I00) and Generalitat Valenciana (Project PROMETEO/2020/063) is acknowledged

    Determinants of highly active antiretroviral therapy duration in HIV-1-infected children and adolescents in Madrid, Spain, from 1996 to 2012

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    © 2014 Palladino et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Objectives To investigate the duration of sequential HAART regimens and predictors of first-line regimen discontinuation among HIV-1 vertically infected children and adolescents. Design Multicentre survey of antiretroviral-naïve patients enrolled in the HIV-Paediatric Cohor,t CoRISpeS-Madrid Cohort, Spain. Methods Patients with a follow-up of ≥1 month spent on HAART, with available baseline CD4 count and HIV-viral load (VL) were included. Time spent on sequential HAART regimens was estimated and multivariable regression was used to identify predictors of time to first-line regimen discontinuation. Results 104 patients were followed for a median 8 years after starting HAART among 1996–2012; baseline %CD4 was 21.5 (12.3–34.0)and viral load was 5.1 (4.6–5.6) log10 copies/mL. Patients received a mean of 1.9 regimens. Median time on first-line HAART (n = 104) was 64.5 months; second HAART (n = 56) 69.8 months; and third HAART (n = 21) 66.5 months. Eleven (11%) patients were lost to follow-up while on first-line HAART and 54% discontinued (cumulative incidence of 16% and 38% by 1 and 3-year, respectively). The main predictor of first-line regimen discontinuation was suboptimal adherence to antiretrovirals (AHR: 2.60; 95% CI: 1.44–4.70). Conclusions Adherence to therapy was the main determinant of the duration of the first-line HAART regimen in children. It is important to identify patients at high risk for non-adherence, such as very young children and adolescents, in provide special care and support to those patients.This work was supported by grants provided by the Fondo de Investigación de Sanidad en España (FIS) [grant numbers PI11-00888, PS09/02029, and PI13/02016], Red Española de Investigación en SIDA (RIS) [grant numbers RETIC RD06/0006/0035 RD12-0017-0037; RD06/0006/0021, RD12/0017/0029 and RD09/0076/00103], “Fundación para la Investigación y la Prevención del Sida en España” (FIPSE), Comunidad de Madrid [grant numbers, S-2010/BMD-2351, S-2010/BMD-2332], PENTA and Fundación Eugenio Rodríguez Pascual and grants PTDC/SAU-FAR/115290/2009 and PTDC/SAU-EPI/122400/2010 from Fundação para a Ciência e Tecnologia (FCT) (http://www.fct.pt), Portugal. Claudia Palladino is supported by the Portuguese Fundação para a Ciência e Tecnologia (FCT) (SFRH/BPD/77448/2011). Verónica Briz is supported by the Spanish Fondo de Investigación Sanitaria (Sara Borrell CD09/00433. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

    Mantle-cell lymphoma genotypes identified with CGH to BAC microarrays define a leukemic subgroup of disease and predict patient outcome

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    To identify recurrent genomic changes in mantle cell lymphoma (MCL), we used high-resolution comparative genomic hybridization (CGH) to bacterial artificial chromosome (BAC) microarrays in 68 patients and 9 MCL-derived cell lines. Array CGH defined an MCL genomic signature distinct from other B-cell lymphomas, including deletions of 1p21 and 11q22.3-ATM gene with coincident 10p12-BMI1 gene amplification and 10p14 deletion, along with a previously unidentified loss within 9q21-q22. Specific genomic alterations were associated with different subgroups of disease. Notably, 11 patients with leukemic MCL showed a different genomic profile than nodal cases, including 8p21.3 deletion at tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor gene cluster (55% versus 19%; P = .01) and gain of 8q24.1 at MYC locus (46% versus 14%; P = .015). Additionally, leukemic MCL exhibited frequent IGVH mutation (64% versus 21%; P = .009) with preferential VH4-39 use (36% versus 4%; P = .005) and followed a more indolent clinical course. Blastoid variants, increased number of genomic gains, and deletions of P16/INK4a and TP53 genes correlated with poorer outcomes, while 1p21 loss was associated with prolonged survival (P = .02). In multivariate analysis, deletion of 9q21-q22 was the strongest predictor for inferior survival (hazard ratio [HR], 6; confidence interval [CI], 2.3 to 15.7). Our study highlights the genomic profile as a predictor for clinical outcome and suggests that "genome scanning" of chromosomes 1p21, 9q21-q22, 9p21.3-P16/INK4a, and 17p13.1-TP53 may be clinically useful in MCL
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