Correlating synthesis parameters with physicochemical properties of poly(glycerol sebacate)

[EN] Poly(glycerol sebacate), PGS, is an elastomeric biodegradable polyester increasingly proposed in a variety of biomedical applications. It is prepared by polycondensation of sebacic acid and glycerol in a first stage in which a prepolymer is obtained, followed by a curing to conveniently crosslink it. In this work, synthesis parameters such as the curing temperature and time, and the molar ratio between reactants, were systematically varied to correlate them with the physicochemical properties of the resulting polymer networks. The efficiency of each manufacturing process was quantified through, the relative mass effectively crosslinked and insoluble in tetrahydrofuran. Infrared spectra gave an estimation of the ratio of non-condensed polar terminal groups. These results were correlated with swelling results, which in turn provided the means to calculate the chains density through Flory-Rehner equilibrium swelling equation for lightly crosslinked polymers. The role of the synthesis parameters on the physical state of the resulting polymers, as well as their proneness to hydrolyze, were followed. The results obtained highlight the relevance of rinsing them following synthesis, to remove non-crosslinked chains that easily diffuse to the surrounding medium. Curing under mild conditions equimolar mixtures of sebacic acid and glycerol proved to lead to poorly crosslinked swellable networks, which hydrolyze easily in bulk mode. Alternative molar ratios yield sticky and difficult to handle materials at higher polyol fractions in the reactive mixture, whilst an excess of acid terminal groups leads to a faster mass loss by hydrolysis in aqueous media together with surface salts deposition, concomitant with a lesser cell viability in in vitro culture. PGS synthesized from an equimolar ratio between reactants and cured at 130 degrees C or higher, for 48 h or longer, show suitable features for their use in tissue engineering applications where hydrophobic surface-degradable rubbers are required, without significant differences among them.The authors acknowledge Spanish Ministerio de Economia y Competitividad through DPI2015-65401-C3-2-R project.Conejero-Garcia, Á.; Rivero-Gimeno, H.; Moreno-Sáez, Y.; Vilarino-Feltrer, G.; Ortuño-Lizarán, I.; Vallés Lluch, A. (2017). Correlating synthesis parameters with physicochemical properties of poly(glycerol sebacate). European Polymer Journal. 87:406-419. https://doi.org/10.1016/j.eurpolymj.2017.01.001S4064198

Synthesis and characterization of nanocrystalline cellulose derived from Pineapple peel residues

Pineapple peel biomass was used as raw material for nanocellulose extraction. The raw material is a residue from the Costa Rican fruit industry. The nanocellulose was obtained by a two-step hydrolysis process. Firstly, the cellulose was hydrolyzed with HCl to obtain microcrystalline cellulose. In the second step, the hydrolysis was carried out using H2SO4 to obtain smaller fragments and decrease the lignin content. A time-dependent study was carried out to determine the particle size decrease depending on the contact time with the H2SO4. The chemical, thermal and morphological properties were analyzed by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering (DLS), zeta potential, atomic force microscopy (AFM) and scanning electron microscopy (SEM). The nanofiber-like cellulose was obtained after 60 minutes of exposure to 65 wt% H2SO4

Extracellular matrix deposition and remodeling after corneal alkali burn in mice

Corneal transparency relies on the precise arrangement and orientation of collagen fibrils, made of mostly Type I and V collagen fibrils and proteoglycans (PGs). PGs are essential for correct collagen fibrillogenesis and maintaining corneal homeostasis. We investigated the spatial and temporal distribution of glycosaminoglycans (GAGs) and PGs after a chemical injury. The chemical composition of chondroitin sulfate (CS)/dermatan sulfate (DS) and heparan sulfate (HS) were characterized in mouse corneas 5 and 14 days after alkali burn (AB), and compared to uninjured corneas. The expression profile and corneal distribution of CS/DSPGs and keratan sulfate (KS) PGs were also analyzed. We found a significant overall increase in CS after AB, with an increase in sulfated forms of CS and a decrease in lesser sulfated forms of CS. Expression of the CSPGs biglycan and versican was increased after AB, while decorin expression was decreased. We also found an increase in KS expression 14 days after AB, with an increase in lumican and mimecan expression, and a decrease in keratocan expression. No significant changes in HS composition were noted after AB. Taken together, our study reveals significant changes in the composition of the extracellular matrix following a corneal chemical injury

Registro fotográfico de un murciélago capturado por Leopardus pardalis (Carnivora: Felidae) en la Reserva de la Biosfera de Calakmul, México

The ocelot faces conservation problems throughout its distribution, mainly due to illegal hunting and habitat transformation. It has been documented that the ocelot diet consists mainly of small nocturnal terrestrial mammals, especially rodents, although it has also been recorded that they can feed on possums, squirrels, rabbits, primates, iguanas, frogs, birds, fish, insects and terrestrial crabs.This note is relevant to the feeding behavior of ocelots in Mexico because it describes a photographic event of an ocelot feeding on a bat, the record was obtained with camera traps placed in the southern core zone of the Calakmul Biosphere Reserve. These cameras were installed to record that species of fauna visitrificiales drinkers (water sources constantly supplied by members of the project) that were placed as part of a pilot project in the years 2018 and 2019 and aim to supply water in the RBC for use of wildlife. As a result of this effort, this photographic record was obtained of an ocelot individual feeding on a bat associated with an artificial drinker.El ocelote enfrenta problemas de conservación a lo largo de su distribución, debido principalmente a la caza ilegal y transformación del hábitat. Se ha documentado que la dieta del ocelote consiste principalmente de pequeños mamíferos terrestres nocturnos, especialmente roedores , aunque también se ha registrado que pueden alimentarse de zarigüeyas, ardillas, conejos, primates, iguanas, ranas, aves, peces, insectos y cangrejos terrestres. La presente nota resulta relevante sobre el comportamiento alimentario de los ocelotes en Mexico debido a que se describe un evento fotográfico de un ocelote alimentándose de un murciélago, el registro fue obtenido con trampas cámara colocadas en la zona nucleo sur de la Reserva de la Biosfera de Calakmul . Estas camaras fueron instaladas para registrar que especies de fauna visitan a los bebederos ariticiales (fuentes de agua abastecidas constantemente por miembros del proyecto) que fueron colocados como parte de un proyecto piloto en los años 2018 y 2019 y tienen como objetivo el abastecimiento de agua en la RBC para uso de la fauna silvestre. Cómo resultado de este esfuerzo, se obtuvo el presente registro fotográfico de un individuo de ocelote alimentandose de un murcielago asociado a un bebedero artificial. &nbsp

Uso de bebederos artificiales por el sereque centroamericano (Dasyprocta punctata) en la reserva de la biosfera de Calakmul, México

Objective: To describe the use of artificial drinking fountains by the central American Agouti (Dasyprocta punctata) in the Calakmul Biosphere Reserve. Design/methodology/approach: Eight artificial drinking fountains were monitored each one with a trap camera with the aim to estimate the relative abundance index and activity patterns of visits to the drinking fountains. The monitoring was during the dry season of 2019. The analyzes were carried out with the InfoStat and R programs. Results: From January to May 2019, with a sampling effort of 1121 days/camera, average abundance of 160.08±85.44. The pattern of visits to the drinking troughs was mainly diurnal. Limitations of the study/implications: The use of trap cameras in the artificial drinking fountains allows us to know the extent of habitat modification in the Calakmul Biosphere Reserve. Findings/conclusions: The implementation of artificial drinking fountains in the RBC during the dry season was a successful action to mitigate the effects of water scarcity. The use of the water resource by the Central American Agouti in artificial drinking fountains was constant, other species of mammals and birds were also observed making use of artificial drinking fountains.Objetivo: Describir el uso de bebederos artificiales por el sereque (Dasyprocta punctata) en la Reserva de la Biosfera de Calakmul. Diseño/metodología/aproximación: Se monitorearon ocho bebederos artificiales cada uno con una cámara trampa con la finalidad de estimar el índice de abundancia relativa y los patrones de actividad de visitas a los bebederos. El monitoreo fue durante la temporada de secas del 2019. Los análisis se realizaron con los programas R e InfoStat. Resultado: De enero a mayo de 2019, con un esfuerzo de muestreo fue de 1121 días/cámara, abundancia promedio de 160.08±85.44. El patrón de visitas a los bebederos fue principalmente diurno. Limitaciones/implicaciones: El uso de cámaras trampa en los bebederos artificiales nos permite conocer los alcances en la modificación del hábitat en la Reserva de la Biosfera de Calakmul (RBC). Hallazgos/conclusiones: La implementación de bebederos artificiales en la RBC durante la temporada de seca fue una acción de éxito para mitigar los efectos de la escases de agua. El aprovechamiento del recurso agua por el sereque en los bebederos artificiales fue constante, también se observaron otras especies de mamíferos y aves haciendo uso de los bebederos artificiales

Novel Peptides with Dual Properties for Treating Pseudomonas aeruginosa Keratitis::Antibacterial and Corneal Wound Healing

The corneal epithelium is a layer in the anterior part of eye that contributes to light refraction onto the retina and to the ocular immune defense. Although an intact corneal epithelium is an excellent barrier against microbial pathogens and injuries, corneal abrasions can lead to devastating eye infections. Among them, Pseudomonas aeruginosa-associated keratitis often results in severe deterioration of the corneal tissue and even blindness. Hence, the discovery of new drugs able not only to eradicate ocular infections, which are often resistant to antibiotics, but also to elicit corneal wound repair is highly demanded. Recently, we demonstrated the potent antipseudomonal activity of two peptides, Esc(1-21) and its diastereomer Esc(1-21)-1c. In this study, by means of a mouse model of P. aeruginosa keratitis and an in vivo corneal debridement wound, we discovered the efficacy of these peptides, particularly Esc(1-21)-1c, to cure keratitis and to promote corneal wound healing. This latter property was also supported by in vitro cell scratch and ELISA assays. Overall, the current study highlights Esc peptides as novel ophthalmic agents for treating corneal infection and injury, being able to display a dual function, antimicrobial and wound healing, rarely identified in a single peptide at the same micromolar concentration range

Estudio para la mejora de la calidad del Máster en Trabajo Social Comunitario, Gestión y Evaluación de Servicios Sociales en atención a las necesidades del alumnado egresado

Se presenta el informe sobre el desarrollo del proyecto de innovación en calidad llevado a cabo por un equipo interdisciplinar en la Facultad de Trabajo Social. A través de la creación de un cuestionario y un grupo de discusión se analiza la inserción laboral y satisfacción con la titulación de nuestros egresados

Immunotherapy with CAR-T cells in paediatric haematology-oncology

[ES] A pesar de ser una enfermedad rara, el cáncer es la primera causa de mortalidad por enfermedad durante la edad pediátrica en los países desarrollados. En este momento, la irrupción de nuevos tratamientos como la inmunoterapia constituye un nuevo paradigma clínico y regulatorio. Uno de estos tipos de inmunoterapia es la inmunoterapia celular. En particular, los medicamentos de terapia avanzada con receptores antigénicos quiméricos en los linfocitos T (CAR-T), y en concreto las células CAR-T19, han supuesto un nuevo escenario en el abordaje de los tumores hematológicos, como la leucemia aguda linfoblástica y los linfomas de células tipo B. La aprobación por las autoridades regulatorias de tisagenlecleucel y axicabtagene ciloleucel, ha impulsado la puesta en marcha del Plan Nacional de Terapias Avanzadas-Medicamentos CAR-T en España, evidenciándose no solo la conveniencia de identificar los centros más adecuados para su administración, sino la necesidad de que estos sufran una profunda transformación para que su actividad asistencial se extienda en algunos casos a la capacidad de fabricación propia de este tipo de terapias. Los hospitales especializados en hematooncología pediátrica tienen por tanto el reto de evolucionar hacia un modelo asistencial que integre la inmunoterapia celular, dotándose de capacidad propia para gestionar todos los aspectos relativos al uso, fabricación y administración de estos nuevos tratamientos. [EN] Despite being a rare disease, cancer is the first cause of mortality due to disease during the paediatric age in the developed countries. The current, great increase in new treatments, such as immunotherapy, constitutes a new clinical and regulatory paradigm. Cellular immunotherapy is one of these types of immunotherapy. In particular, the advanced therapy drugs with chimeric antigen receptors in the T-lymphocytes (CAR-T), and particularly the CAR-T19 cells, has opened up a new scenario in the approach to haematology tumours like acute lymphoblastic leukaemia and the B-Cell lymphomas. The approval of tisagenlecleucel and axicabtagene ciloleucel by the regulatory authorities has led to the setting up of the National Plan for Advanced Therapies-CAR-T drugs in Spain. There is evidence of, not only the advantage of identifying the centres most suitable for their administration, but also the need for these to undergo a profound change in order that their healthcare activity is extended, in some cases, to the ability for the in-house manufacture of these types of therapies. The hospitals specialised in paediatric haematology-oncology thus have the challenge of progressing towards a healthcare model that integrates cellular immunotherapy, having the appropriate capacity to manage all aspects relative to their use, manufacture, and administration of these new treatments.S

Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age