El poder paralelo de las ONG en Guatemala

Las organizaciones no gubernamentales van abarcando cada vez más parcelas de poder en países con instituciones frágiles, como Guatemala. Algunas desarrollan un trabajo socialmente útil, pero otras se dedican a actividades más prosaicas, aprovechando la falta de control de los donantes. Las organizaciones no gubernamentales (ONG) se han convertido, desde hace unos años, en parte consustancial del paisaje cotidiano de Guatemala, como los volcanes, la delincuencia o los autobuses multicolores. Más de 500 entidades locales han ido ocupando los espacios desatendidos por un Estado débil e inoperante, y pocos de los 12 millones de guatemaltecos no han escuchado alguna vez los términos “proyecto”, “financiación” o “desarrollo integral”. La ausencia de fiscalización ha permitido que en ese piélago humanitario florezca la picaresca, y que el rótulo de “ONG” sirva de tapadera para negocios, corrupción y tráfico de influencias, como han puesto de manifiesto escándalos recientes. Del análisis crítico tampoco salen indemnes las organizaciones de derechos humanos, cuya “lucha contra la impunidad” suele disfrazar intereses políticos y corporativos. Arropados por la comunidad internacional, estos grupos han conformado un poder paralelo que condiciona las agendas de los gobiernos de turno

Estudio de la influencia de un modificador termoplástico polidisperso sobre una matriz epoxi-amina. Morfología, curado y separación de fases

[Resumen] El objetivo principal es estudiar termodinámicamente la separación de fases en diferentes sistemas epoxi-amina modificados con un termoplástico (poliestireno, PS), y caracterizar los materiales finales desde el punto de vista de la morfología, la estabilidad térmica y las transiciones vítreas, así como la caracterización de la reacción epoxi-amina; correlacionando los resultados termodinámicos, con las morfologías y con otras propiedades mostradas por los materiales. Además, en este trabajo se pretende estudiar la evolución del comportamiento de estos materiales cuando la estructura molecular del sistema epoxi-amina se modifica continuamente desde la correspondiente a un polímero lineal hasta la del polímero altamente entrecruzado, utilizando para ello la formulación, con concentraciones preestablecidas de la monoamina aminodifenilmetano (ADM) y la diamina 4,4'-metilenebis(2,6-dietilanilina) (MDEA). El precursor epoxi utilizado fue el diglicidiléter de bisfenol A (DGEBA). De esta forma, se analizará el efecto de las variables: concentración de modificador, temperatura de polimerización y estructura del sistema epoxi-amina (dada por la proporción de monoamina-diamina en el sistema), sobre la separación de fases, las morfologías y las demás propiedades analizadas en los materiales de estudio

Influence of the Hydrophilicity of Montmorillonite on Structure and Properties of Thermoplastic Wheat Starch/Montmorillonite Bionanocomposites

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] The increasing environmental pollution with petroleum-based plastics has advanced research on biodegradable polymers. Thermoplastic starch (TPS) is one promising candidate due to wide availability from various renewable sources, low cost and biodegradability. However, TPS has significant shortcomings, as high water sensitivity and low mechanical properties. An approach to overcome these drawbacks is adding nanofillers as reinforcement of the starch matrix. Among the nanofillers, montmorillonite clays have the advantages of a wide availability, low cost, versatility and environmental friendliness. Bionanocomposites based on wheat starch plasticized with glycerol and reinforced with three types of montmorillonite nanoclays, one natural (Cloisite Na+) and two organomodified (Cloisite 30B and Cloisite 10A), were prepared by melt processing. The effect of nanoclay type and amount on processing properties, thermal stability, dynamic mechanical properties and water absorption was widely investigated. The properties strongly depended on the dispersion state of the nanoclay in the TPS matrix. The dispersion improved with the hydrophilicity of the nanoclay. Cloisite Na+, the most hydrophilic nanoclay, was the most effective in reinforcing TPS, improving the thermal stability and the dynamic mechanical properties, and showing a greater resistance to water absorption in normal humidity environments. Bionanocomposites of TPS andCloisite Na+ can be a good alternative for use in packaging applications.Xunta de Galicia; ED431C 2019/1

Effect of different plasticizers on thermal, crystalline, and permeability properties of Poly(3–hydroxybutyrate–co-3–hydroxyhexanoate)films

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) films were prepared using a cast film technique. Dioxane was chosen over other polymer solvents as it resulted in homogenous films with better morphology. Several plasticizers with different molecular weights and concentrations were added to the biopolymer solution prior to casting. Thermal, crystalline, and permeability properties were analyzed by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and both water vapor and oxygen transmission rate analysis. In general, the addition of plasticizers decreased the glass transition temperature (Tg), cold crystallization temperatures (Tcc), melting temperatures, as well as crystallinity degrees and increased the crystallite sizes and water vapor and oxygen transmission rates. The use of isosorbide and low-molecularweight poly(ethylene glycol) (PEG) lowered the Tg around 30 C at the highest used concentration, also being the most effective in increasing the crystallite size. When considering isosorbide and low-molecular-weight poly(ethylene glycol) (PEG) as very good plasticizers for PHBH, the question of which plasticizer to use strongly relies on the desired PHBH application.Xunta de Galicia; GPC IN607B2019/10Xunta de Galicia; ED431C 2019/1

Preparation and Characterization of Bionanocomposite Films Based on Wheat Starch and Reinforced With Cellulose Nanocrystals

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] In recent times, the attention of scientific community has been focusing on the replacement of petroleum-based polymers by others more environmentally friendly. In this sense, bionanocomposites based on glycerol-plasticized wheat starch and reinforced with cellulose nanocrystals (CNCs) were prepared by a solvent-casting process to obtain environmentally friendly films. The plasticization process was proven to be complete in the conditions used and no residual crystallinity was observed in any case. The incorporation of CNCs leads to materials with increased rigidity (about 1000% increment in modulus) which is related to a good filler-matrix interaction and to the formation of a rigid crystalline network of cellulose. This fact allowed also to improve the moisture resistance and the barrier properties (in both, oxygen and water vapor as permeant) of the bionanocomposite films due to the formation of a tortuous path, which prevent the gas diffusion. Moreover, the thermal stability of films was not affected by the filler incorporation. These improvements in the properties make these films susceptible to be used in short-time applications in the food packaging industry.Xunta de Galicia; ED431C 2019/17The research leading to these results received funding from the Xunta de Galicia Government: program of consolidation and structuring competitive research units [Grant number: ED431C 2019/17]. Funding for open access charge was provided by Universidade da Coruña/CISUG

Injectable hybrid hydrogels physically crosslinked based on carrageenan and green graphene for tissue repair

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] Injectable and biocompatible novel hybrid hydrogels based on physically crosslinked natural biopolymers and green graphene for potential use in tissue engineering are reported. Kappa and iota carrageenan, locust bean gum and gelatin are used as biopolymeric matrix. The effect of green graphene content on the swelling behavior, mechanical properties and biocompatibility of the hybrid hydrogels is investigated. The hybrid hydrogels present a porous network with three-dimensionally interconnected microstructures, with lower pore size than that of the hydrogel without graphene. The addition of graphene into the biopolymeric network improves the stability and the mechanical properties of the hydrogels in phosphate buffer saline solution at 37 °C without noticeable change in the injectability. The mechanical properties of the hybrid hydrogels were enhanced by varying the dosage of graphene between 0.025 and 0.075 w/v%. In this range, the hybrid hydrogels preserve their integrity during mechanical test and recover the initial shape after removing the applied stress. Meanwhile, hybrid hydrogels with graphene content of up to 0.05 w/v% exhibit good biocompatibility for 3T3-L1 fibroblasts; the cells proliferate inside the gel structure and show higher spreading after 48 h. These injectable hybrid hydrogels with graphene have promising future as materials for tissue repair.Xunta de Galicia; ED431C 2019/17Instituto de Salud Carlos III; CD21/00042Chile. CORFO; 22CVID-20683

Recent Emergence of Dengue Virus Serotype 4 in French Polynesia Results from Multiple Introductions from Other South Pacific Islands

BACKGROUND: Infection by dengue virus (DENV) is a major public health concern in hundreds of tropical and subtropical countries. French Polynesia (FP) regularly experiences epidemics that initiate, or are consecutive to, DENV circulation in other South Pacific Island Countries (SPICs). In January 2009, after a decade of serotype 1 (DENV-1) circulation, the first cases of DENV-4 infection were reported in FP. Two months later a new epidemic emerged, occurring about 20 years after the previous circulation of DENV-4 in FP. In this study, we investigated the epidemiological and molecular characteristics of the introduction, spread and genetic microevolution of DENV-4 in FP. METHODOLOGY/PRINCIPAL FINDINGS: Epidemiological data suggested that recent transmission of DENV-4 in FP started in the Leeward Islands and this serotype quickly displaced DENV-1 throughout FP. Phylogenetic analyses of the nucleotide sequences of the envelope (E) gene of 64 DENV-4 strains collected in FP in the 1980s and in 2009-2010, and some additional strains from other SPICs showed that DENV-4 strains from the SPICs were distributed into genotypes IIa and IIb. Recent FP strains were distributed into two clusters, each comprising viruses from other but distinct SPICs, suggesting that emergence of DENV-4 in FP in 2009 resulted from multiple introductions. Otherwise, we observed that almost all strains collected in the SPICs in the 1980s exhibit an amino acid (aa) substitution V287I within domain I of the E protein, and all recent South Pacific strains exhibit a T365I substitution within domain III. CONCLUSIONS/SIGNIFICANCE: This study confirmed the cyclic re-emergence and displacement of DENV serotypes in FP. Otherwise, our results showed that specific aa substitutions on the E protein were present on all DENV-4 strains circulating in SPICs. These substitutions probably acquired and subsequently conserved could reflect a founder effect to be associated with epidemiological, geographical, eco-biological and social specificities in SPICs

Transcriptome characterization by RNA sequencing identifies a major molecular and clinical subdivision in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) has heterogeneous clinical and biological behavior. Whole-genome and -exome sequencing has contributed to the characterization of the mutational spectrum of the disease, but the underlying transcriptional profile is still poorly understood. We have performed deep RNA sequencing in different subpopulations of normal B-lymphocytes and CLL cells from a cohort of 98 patients, and characterized the CLL transcriptional landscape with unprecedented resolution. We detected thousands of transcriptional elements differentially expressed between the CLL and normal B cells, including protein-coding genes, noncoding RNAs, and pseudogenes. Transposable elements are globally derepressed in CLL cells. In addition, two thousand genes-most of which are not differentially expressed-exhibit CLL-specific splicing patterns. Genes involved in metabolic pathways showed higher expression in CLL, while genes related to spliceosome, proteasome, and ribosome were among the most down-regulated in CLL. Clustering of the CLL samples according to RNA-seq derived gene expression levels unveiled two robust molecular subgroups, C1 and C2. C1/C2 subgroups and the mutational status of the immunoglobulin heavy variable (IGHV) region were the only independent variables in predicting time to treatment in a multivariate analysis with main clinico-biological features. This subdivision was validated in an independent cohort of patients monitored through DNA microarrays. Further analysis shows that B-cell receptor (BCR) activation in the microenvironment of the lymph node may be at the origin of the C1/C2 differences

Dolutegravir twice-daily dosing in children with HIV-associated tuberculosis: a pharmacokinetic and safety study within the open-label, multicentre, randomised, non-inferiority ODYSSEY trial

Background: Children with HIV-associated tuberculosis (TB) have few antiretroviral therapy (ART) options. We aimed to evaluate the safety and pharmacokinetics of dolutegravir twice-daily dosing in children receiving rifampicin for HIV-associated TB. Methods: We nested a two-period, fixed-order pharmacokinetic substudy within the open-label, multicentre, randomised, controlled, non-inferiority ODYSSEY trial at research centres in South Africa, Uganda, and Zimbabwe. Children (aged 4 weeks to <18 years) with HIV-associated TB who were receiving rifampicin and twice-daily dolutegravir were eligible for inclusion. We did a 12-h pharmacokinetic profile on rifampicin and twice-daily dolutegravir and a 24-h profile on once-daily dolutegravir. Geometric mean ratios for trough plasma concentration (Ctrough), area under the plasma concentration time curve from 0 h to 24 h after dosing (AUC0–24 h), and maximum plasma concentration (Cmax) were used to compare dolutegravir concentrations between substudy days. We assessed rifampicin Cmax on the first substudy day. All children within ODYSSEY with HIV-associated TB who received rifampicin and twice-daily dolutegravir were included in the safety analysis. We described adverse events reported from starting twice-daily dolutegravir to 30 days after returning to once-daily dolutegravir. This trial is registered with ClinicalTrials.gov (NCT02259127), EudraCT (2014–002632-14), and the ISRCTN registry (ISRCTN91737921). Findings: Between Sept 20, 2016, and June 28, 2021, 37 children with HIV-associated TB (median age 11·9 years [range 0·4–17·6], 19 [51%] were female and 18 [49%] were male, 36 [97%] in Africa and one [3%] in Thailand) received rifampicin with twice-daily dolutegravir and were included in the safety analysis. 20 (54%) of 37 children enrolled in the pharmacokinetic substudy, 14 of whom contributed at least one evaluable pharmacokinetic curve for dolutegravir, including 12 who had within-participant comparisons. Geometric mean ratios for rifampicin and twice-daily dolutegravir versus once-daily dolutegravir were 1·51 (90% CI 1·08–2·11) for Ctrough, 1·23 (0·99–1·53) for AUC0–24 h, and 0·94 (0·76–1·16) for Cmax. Individual dolutegravir Ctrough concentrations were higher than the 90% effective concentration (ie, 0·32 mg/L) in all children receiving rifampicin and twice-daily dolutegravir. Of 18 children with evaluable rifampicin concentrations, 15 (83%) had a Cmax of less than the optimal target concentration of 8 mg/L. Rifampicin geometric mean Cmax was 5·1 mg/L (coefficient of variation 71%). During a median follow-up of 31 weeks (IQR 30–40), 15 grade 3 or higher adverse events occurred among 11 (30%) of 37 children, ten serious adverse events occurred among eight (22%) children, including two deaths (one tuberculosis-related death, one death due to traumatic injury); no adverse events, including deaths, were considered related to dolutegravir. Interpretation: Twice-daily dolutegravir was shown to be safe and sufficient to overcome the rifampicin enzyme-inducing effect in children, and could provide a practical ART option for children with HIV-associated TB