Development, characterization and sterilisation of Nanocellulose-alginate-(hyaluronic acid)- bioinks and 3D bioprinted scaffolds for tissue engineering

3D-bioprinting is an emerging technology of high potential in tissue engineering (TE), since it shows effective control over scaffold fabrication and cell distribution. Biopolymers such as alginate (Alg), nanofibrillated cellulose (NC) and hyaluronic acid (HA) offer excellent characteristics for use as bioinks due to their excellent biocompatibility and rheological properties. Cell incorporation into the bioink requires sterilisation assurance, and autoclave, β-radiation and γ-radiation are widely used sterilisation techniques in biomedicine; however, their use in 3D-bioprinting for bioinks sterilisation is still in their early stages. In this study, different sterilisation procedures were applied on NC-Alg and NC-Alg-HA bioinks and their effect on several parameters was evaluated. Results demonstrated that NC-Alg and NC-Alg-HA bioinks suffered relevant rheological and physicochemical modifications after sterilisation; yet, it can be concluded that the short cycle autoclave is the best option to sterilise both NC-Alg based cell-free bioinks, and that the incorporation of HA to the NC-Alg bioink improves its characteristics. Additionally, 3D scaffolds were bioprinted and specifically characterized as well as the D1 mesenchymal stromal cells (D1-MSCs) embedded for cell viability analysis. Notably, the addition of HA demonstrates better scaffold properties, together with higher biocompatibility and cell viability in comparison with the NC-Alg scaffolds. Thus, the use of MSCs containing NC-Alg based scaffolds may become a feasible tissue engineering approach for regenerative medicine.Author thanks the Basque Government for granted fellowship to S. Ruiz-Alonso (PRE_2020_2_0143). This study was financially supported by the Basque Country Government (IT907-16), the Ministerio de Economía, Industria y Competitividad (FEDER funds, project RTC-2016- 5451-1), Fundación Mutua Madrileña (project FMM-AP17196-2019), the Instituto de Salud Carlos III, ERDF funds (DTS19/00145) and by the Consejería de Economía, Conocimiento, Empresas y Universidad, Junta de Andalucía (project no. PY18-2470 and SOMM17/6109/UGR, FEDER Funds). Authors also wish to thank the intellectual and technical assistance from the ICTS “NANBIOSIS”, more specifically by the Drug Formulation Unit (U10) of the CIBER in Bioengineering, Biomaterials & Nanomedicine (CIBER-BBN) at the University of Basque Country (UPV/ EHU

Anales de Edafología y Agrobiología Tomo 34 Número 3-4

Estudio de la materia orgánica del ranker atlántico. I. Caracterización general, por P. Rodríguez Seoane, T. Carballas y F. Guitián Ojea.-- Movimiento y distribución de sales solubles en suelos calizos, por F. G. Fernández, M. Caro y A. Cerda.-- The availability of added and native phosphorus to barley grown in sorne Egyptian soils .containing different levels of calciurn carbonate, by M. H. Nafady.-- The measurernent of soil pH in calciurn chloride solutions, by M. H. Nafady.- Nuevas aportaciones al conocimiento del género Mnema (nernatoda) y su distribución en los suelos españoles, por María Arias.-- Estudios bioquímicos y fisiológicos en aceituna. III. Variaciones en el crecimiento de hojas y frutos, por J. P. Donaire, A. J. Sánchez-Raya, J. López Corge y L. Recalde.-- Importancia de la rnicorrización espontánea en ensayos de nutrición vegetal en suelos deficientes en fósforo, por R. Azcón y J. M. Barea.-- Andosoles canarios. J. Características generales de estos suelos, por E. Fernández Caldas y M. L. Tejedor Salguero.-- Andosoles canarios. II. Intergrados andosol-tierra parda oligotrófica. Características morfológicas y quírnkas, por M. L. Tejedor Salguero y E. Fernández Caldas.-- Andosoles canarios. lll. Jntergrados andosol-tierra parda otigotrófica. Catacterísticas físicas, por E. Fernández Caldas y M. L. Tejedor Salguero.-- Andosoles canario;. IV. In ter grados andosol-tierra parda ohgotrófica. Características mineralógicas. Interpretación y clasificación, por C. Rodríguez Pascual, P. Quantin, M. L. Tejedor Salguero y E. Fernández Caldas.-- Estudios recapitualtivos.-- La vid una revisión de las condiciones del cultivo, por C. González O. y M. Lachica.—Notas científicas.-- Nota sobre la determinación del carbono orgánico en suelos, por J. F. Gallardo.—Notas.-- Ampliación de la Comisión Permanente de la Junta de Gobierno del Patronato Alonso de Herrera.-- Nombramiento de Secretario del Centro de Edafología y Biología Aplicada de Tenerife.-- Nombramientos en el Instituto de Alimentación v Productividad Animal.-- Cambio de representantes del Patronato Alonso de Herrera en la Comisión Asesora de la Investigación Científica y Técnica.-- Convenio con ASPA.-- Dimisión del Director del Centro de Edafología y Biología Aplicada del Segura de Murcia.-- Nombramientos de representantes en los C. R. l. D. A. S.-- Designación de Jurados para Premios del C. S. l. C.-- Informes del Secretario Adjunto del C. S. I. C. sobre reuniones en Europa.-- Convenio entre la Estación Experimental del Zaidín y la Universidad de Nápoles.-- Donación de terrenos a la Diputación de Badajoz.-- Seminario Oleícola Internacional.-- Congreso de la Unión Fitopatológica Mediterránea.-- Situaciones de personal.-- Reunión de la Comisión de Protección Vegetal.-- Día Forestal Mundial.-- Congresos y reuniones internacionales y viajes.-- Premio Agrícola Aedos.-- BibliografíaPeer reviewed2019-08.- CopyBook.- Libnova.- Biblioteca ICA

Anales de Edafología y Agrobiología Tomo 32 Número 9-10

Aportaciones para un mejor conocimiento de los suelos desarrollados sobre materiales calizos consolidados, por J. L. Moreno Alvarez y T. Badorrey Peracho.-- Estudio biológico y químico de Erica umbellata L., por M. Consolación Salas, Antonio Ballester y Ernesto Vieitez.--Contenido en metales de la nitrito reductasa del alga Chlorella, por J. Cárdenas, F. D. Pineda, F. F. de la Rosa, J. L. Barea y J. Rivas.-- Andosuelos de la provincia de Gerona. I. Estudio de sustancias minerales amorfas, por J. Rodríguez Sanchidrián y F Monturiol Rodríguez.-- Minerales de la arcilla en suelos de la provincia de Granada, por J. L. Martín Vivaldi, E. Galán Huertos y F. López Aguayo.-- Influence of foliar application of macro-nutrient on the plant growth and rnultiplication of viruses. I. Foliar application of nitrogen nutrient to tomato and its effect on host growth and potato virus X multiplication, by Rajendra Singh and Tej Pratap Mall.-- Heterodera Schachtii Schmidt, 1871 (Nematoda: Heteroderidae) en los suelos de las Islas Canarias, por A. Bello y Mª. D. Romero.-- Utiliización de una nueva fórmula de cálculo para la evaporación de Piché en regiones húmedas de España, por Jesús Seco, Angela Calvo y José Garmendía.-- Contribución al estudio de la técnica de Walkley y Black para la determinación de carbono orgánico de suelos, por Luisa Prat Pérez y Benito Sánchez.-- Estudio de la dinámica del crecimiento del limón en el sureste español, por O. Carpena, F. Romojaro, C. Alearaz y S. Llorente.-- Efecto de la aplicación de acetileno y ácido 2-cloroetilfosfónico sobre la fructificación y cosecha del olivo, por A. J. Sánchez-Raya, J. P. Donaire y L. Recalde.—Notas científicas.-- Estudio de fosfatasa ácida en plantas de A tropa belladona L. recogidas en otoño, por M. R. Felipe Antón y N. Velázquez Sánchez.—Notas.-- Nombramiento de Presidente del C. S. I. C.-- Constitución de la nueva Junta de Gobierno del Patronato Alonso de Herrera.-- Nombramiento de Consejeros de Número.-- Nombramiento de Consejeros Adjuntos.-- Designación del Comité Nacional de la Unión Internacional de Investigaciones sobre el Cuaternario.-- Rector de la Universidad de La Laguna.-- Distinción al Pro f. Zorita.-- European Grassland Federation (5th General Meeting).-- Reuniones nacionales.-- 1ª Reunión Nacional del Grupo de Trabajo del Cuaternario.-- Laboratorio de Micromorfología de Suelos.-- Próximo Congreso de Micromorfología.-- Reunión en La Mayora.-- BibliografíaPeer reviewed2019-08.- CopyBook.- Libnova.- Biblioteca ICA

Polymeric drugs based on random copolymers with antimitotic activity

Polymeric drugs based on random copolymers with antimitotic activity were obtained by free radical copolymerization of oleyl 2-acetamido-2-deoxy-R-D-glucopyranoside methacrylate (OAGMA) and 2-ethyl-(2- pyrrolidone) methacrylate (EPM) at low and high conversion and analyzed in terms of microstructure, physicochemical, and biological properties. Reactivity ratios of monomers were found to be rOAGMA ) 1.34 and rEPM ) 0.98, indicating the obtaining of statistical copolymers with random sequence distribution of the comonomeric units in the macromolecular chains. The glass transition temperature of the copolymers presents a negative deviation from the predicted values according to the Fox equation, suggesting a higher flexibility of the alternating diad. Copolymeric systems with OAGMA contents between 10-50 mol % presented thermosensitive behavior in a heating process showing cloud point temperatures (CPT) in the range 45-28 °C with increasing OAGMA content and hysteresis in one heating-and-cooling cycle. In vitro glycolipid release studies revealed the stability of the ester group in culture medium. The polymeric drugs with 30 and 50 mol % OAGMA presented antimitotic activity on a human glioblastoma line, but they were less toxic on normal human fibroblast cultures.Financial support from the Comisio´n Interministerial de Ciencia y Tecnología, CICYT, (MAT2007- 63355) and NoE EXPERTISSUES (UE Contract No. 500283- 2) is gratefully acknowledgedPeer reviewe

Glycerylphytate compounds with tunable ion affinity and osteogenic properties

Phytic acid (PA) is a natural-occurring antioxidant, which plays an important role in many biological processes. PA is recognized as a potent inhibitor of lipid peroxidation because of its high affinity to multivalent cations, and it can play a role in osteogenic processes. However, its powerful chelating capacity is controversial because it can lead to a severe reduction of mineral availability in the organism. For this reason, compounds with beneficial biological properties of PA, but a modular ion binding capacity, are of high interest. In this work, we report the synthesis and physicochemical characterization of two hydroxylic derivatives of PA, named glycerylphytates (GPhy), through a condensation reaction of PA with glycerol (G). Both derivatives present antioxidant properties, measured by ferrozine/FeCl method and chelating activity with calcium ions depending on the content of glyceryl groups incorporated. Besides, the hydroxylic modification not only modulates the ion binding affinity of derivatives but also improves their cytocompatibility in human bone marrow mesenchymal cells (MSCs). Furthermore, GPhy derivatives display osteogenic properties, confirmed by COL1A and ALPL expression depending on composition. These positive features convert GPhy compounds into potent alternatives for those skeletal diseases treatments where PA is tentatively applied.The authors thank financial support to Ministry of Science, Innovation and Universities (Spain) (MAT2017- 2017-84277-R), Instituto Salud Carlos III (ISCIII)-Fondo Europeo de Desarrollo Regional (FEDER), MINECOAES (PI18/00643 and PI15/01118). Ana Mora-Boza is supported by “La Caixa” foundation (Scholarship of, code LCF/BQ/ES16/11570018), Laura Saldaña is supported by a Miguel Servet contract from ISCIII-MINECO-AESFEDER- FSE. Nuria Vilaboa is supported by Program I2 from Comunidad Autónoma de Madrid. The authors are indebted to Rosana Ramirez (ICTP-CSIC) and Fatima Bensiamar (IdiPAZ and CIBER-BBN) for excellent technical assistance with cell culture experiments and gene expression analysis, respectively.Peer Reviewe

Polymeric drugs based on bioactive glycosides for the treatment of brain tumours

Polymeric drugs carrying glycolipids have been designed as target macromolecules for the treatment of brain tumours. A methacrylate derivative of oleyl 2-acetamido-2-deoxy-a-D-glucopyranoside (OAGMA) has been prepared and the corresponding glycopolymer obtained by free radical polymerisation. To modulate the hydrophobic character of the polymeric drug, the acrylic glycomonomer was copolymerised with vinyl pyrrolidone (VP). Reactivity ratios obtained by performing copolymerisation reactions inside the NMR apparatus were rOAGMA¼ 5.94 and rVP¼ 0.01, indicating the much higher reactivity of the glycomonomer. The hydrolytical release of oleyl 2-acetamido-2-deoxy-a-D-glucopyranoside (OAG) from the copolymeric drugs was produced in vitro by the ester enzymatic hydrolysis using enzyme/buffered solutions. The cytotoxicity of OAG and OAGMA tested against a human glioblastoma line and normal fibroblasts revealed a concentration dependent selectivity towards tumour cells versus fibroblasts. The antimitotic activity of the copolymeric drugs was also confirmed. The addition of the eluates of the copolymeric systems collected at 1 and 2 days produced a significant decrease in cellular viability of the glioblastoma cells without affecting that of normal fibroblasts. On the contrary, fibroblasts were able to adhere and proliferate onto the copolymeric systems showing normal morphology and revealing a good biocompatibility of the copolymeric drugs against healthy cells.This research was supported by Comisio´n Interministerial de Ciencia y Tecnologı´a, CICYT (MAT2007-63355), CSIC (PIF: 200580F0061-62-63), NoE EXPERTISSUES (UE contract no: 500283- 2) and a Predoctoral Fellowship from the Spanish Ministry of Science and Education (FPU AP2005-0246).Peer reviewe

Amphiphilic self-assembled >polymeric drugs>: Morphology, properties, and biological behavior of nanoparticles

This article reports the fabrication and characterization of NPs based on the self-assembling of polymeric drugs with amphiphilic character synthetized from oleyl 2-acetamido-2-deoxy-α-d-glucopyranoside methacrylate and vinyl pyrrolidone (OAGMA-VP). NPs were spherical, with an apparent hydrodynamic diameter between 91 and 226 nm and with zeta potential values that ensure stability. Atomic concentrations of C, O, and N, determined by X-ray photoelectron spectroscopy (XPS) of NPs, compared well with the corresponding theoretical values. High resolution XPS C1s spectra suggest that the carbons bound to heteroatoms or carbonyl groups are preferentially situated on the surface of the NP samples. ToF-SIMS spectra analyzed by principal component analysis (PCA) indicated that ions coming from acetyl and oleyl groups of OAGMA play important roles in the outer structure of NPs. Water contact angle and surface tension values of NPs were characteristic of hydrophilic surfaces, confirming the location of VP sequences on the surface. Cell culture assays showed that copolymeric NPs did not compromise biocompatibility of human fibroblasts according to ISO standard, but they were cytotoxic on a human glioblastoma cell line (A-172). © 2012 American Chemical Society.Peer Reviewe

A study on partially biodegradable microparticles as carriers of active glycolipids

This paper describes a study on the preparation and characterisation of partially biodegradable microparticles of poly(e-caprolactone)/poly(ethyl methacrylate) (PCL/PEMA) as carriers of synthetic glycolipids with antimitotic activity against brain tumour cells. Microparticles prepared by suspension polymerisation of methacrylate in the presence of already polymerised PCL showed a predominantly spherical but complex morphology, with segregation of PCL micro/nano-domains towards the surface. Small diameter discs were prepared by compression moulding of blends of microparticles and the active principle under mild conditions. The in vitro behaviour of the discs and release of the glycolipid were studied in different simulated fluid models. Ingress of fluids increased with increasing hydrophobicity of the medium. Release of the glycolipid was sustained in all fluids, the most prolonged profile being in human synovial fluid and phosphate-buffered saline modified with 20 vol.% dioxane. Slow disintegration of the discs and partial degradation of the microparticles was evident in accelerated studies. The antimitotic activity of glycolipid released from the discs was proved against a human glioblastoma line. This activity, along with selectivity against human fibroblasts, could be controlled by the amount of drug charged in the disc.This research was supported by the Comisión Interministerial de Ciencia y Tecnología (MAT2007-63355), NoE EXPERTISSUES (UE Contract No. 500283-2), CSIC (PIF 200580F0061-62-63) and a Predoctoral Fellowship from the Spanish Ministry of Science and Education (AP2005-0246). M. Fernández was supported by the Ramón y Cajal programme (MEC-Spain).Peer reviewe

Evaluation of glycerylphytate crosslinked semi- and interpenetrated polymer membranes of hyaluronic acid and chitosan for tissue engineering

n the present study, semi- and interpenetrated polymer network (IPN) systems based onhyaluronic acid (HA) and chitosan using ionic crosslinking of chitosan with a bioactive crosslinker,glycerylphytate (G1Phy), and UV irradiation of methacrylate were developed, characterized andevaluated as potential supports for tissue engineering. Semi- and IPN systems showed significantdifferences between them regarding composition, morphology, and mechanical properties afterphysicochemical characterization. Dual crosslinking process of IPN systems enhanced HA retentionand mechanical properties, providing also flatter and denser surfaces in comparison to semi-IPNmembranes. The biological performance was evaluated on primary human mesenchymal stemcells (hMSCs) and the systems revealed no cytotoxic effect. The excellent biocompatibility of thesystems was demonstrated by large spreading areas of hMSCs on hydrogel membrane surfaces.Cell proliferation increased over time for all the systems, being significantly enhanced in the semi-IPN,which suggested that these polymeric membranes could be proposed as an effective promoter systemof tissue repair. In this sense, the developed crosslinked biomimetic and biodegradable membranescan provide a stable and amenable environment for hMSCs support and growth with potentialapplications in the biomedical field

DEAE/Catechol-Chitosan Conjugates as Bioactive Polymers: Synthesis, Characterization, and Potential Applications

This work provides the first description of the synthesis and characterization of water-soluble chitosan (Cs) derivatives based on the conjugation of both diethylaminoethyl (DEAE) and catechol groups onto the Cs backbone (Cs-DC) in order to obtain a Cs derivative with antioxidant and antimicrobial properties. The degree of substitution [DS (%)] was 35.46% for DEAE and 2.53% for catechol, determined by spectroscopy. Changes in the molecular packing due to the incorporation of both pendant groups were described by X-ray diffraction and thermogravimetric analysis. For Cs, the crystallinity index was 59.46% and the maximum decomposition rate appeared at 309.3 °C, while for Cs-DC, the values corresponded to 16.98% and 236.4 °C, respectively. The incorporation of DEAE and catechol groups also increases the solubility of the polymer at pH > 7 without harming the antimicrobial activity displayed by the unmodified polymer. The catecholic derivatives increase the radical scavenging activity in terms of the half-maximum effective concentration (EC). An EC of 1.20 μg/mL was found for neat hydrocaffeic acid (HCA) solution, while for chitosan-catechol (Cs-Ca) and Cs-DC solutions, concentrations equivalent to free HCA of 0.33 and 0.41 μg/mL were required, respectively. Cell culture results show that all Cs derivatives have low cytotoxicity, and Cs-DC showed the ability to reduce the activity of reactive oxygen species by 40% at concentrations as low as 4 μg/mL. Polymeric nanoparticles of Cs derivatives with a hydrodynamic diameter (D) of around 200 nm, unimodal size distributions, and a negative ζ-potential were obtained by ionotropic gelation and coated with hyaluronic acid in aqueous suspension, providing the multifunctional nanoparticles with higher stability and a narrower size distribution.This work was funded by the Spanish Ministry of Science and Innovation (PID2020-114086RB-100). F.J.C.-L. acknowledges financial support from CONACyT (México) through the scholarship ‘Apoyo para estancias postdoctorales en el extranjero vinculadas a la consolidación de grupos de investigación y fortalecimiento del Posgrado nacional’. M.R.A. and B.V.-L. are members of the SusPlast platform from CSIC. This research work was performed in the framework of the Nanomedicine CSIC HUB (ref 202180E048). The authors thank R.A.R. from (ICTP), CSIC, for assistance in the biological experiment