Supercritical CO2 Synthesis of Porous Metalloporphyrin Frameworks: Application in Photodynamic Therapy.

A series of porous metalloporphyrin frameworks prepared from the 5,10,15,20-tetra(4-pyridyl)porphyrin (H2TPyP) linker and four metal complexes, M(hfac)2 M = Cu(II), Zn(II), Co(II), and Ni(II) (hfac: 1,1,1,5,5,5-hexafluoroacetylacetonate), were obtained using supercritical CO2 (scCO2) as a solvent. All the materials, named generically as [M-TPyP] n , formed porous metal-organic frameworks (MOFs), with surface areas of ∼450 m2 g-1. All MOFs were formed through the coordination of the metal to the exocyclic pyridine moieties in the porphyrin linker. For Cu(II), Zn(II), and Co(II), incomplete metal coordination of the inner pyrrole ring throughout the structure was observed, giving place to MOFs with substitutional defects and leading to a certain level of disorder and limited crystallinity. These samples, prepared using scCO2, were precipitated as nano- to micrometric powders. Separately, a layering technique from a mixture of organic solvents was used to crystallize high-quality crystals of the Co(II) based MOF, obtained with the formula [{Co(hfac)2}2H2TPyP] n . The crystal structure of this MOF was elucidated by single-crystal synchrotron X-ray diffraction. The Zn(II)-based MOF was selected as a potential photodynamic therapy drug in the SKBR-3 tumoral cell line showing outstanding performance. This MOF resulted to be nontoxic, but after 15 min of irradiation at 630 nm, using either 1 or 5 µM concentration of the product, almost 70% of tumor cells died after 72 h.

Photocatalytic Hydrogen Production using Porous 3D Graphene-Based Aerogels Supporting Pt/TiO2 Nanoparticles.

Composites involving reduced graphene oxide (rGO) aerogels supporting Pt/TiO2 nanoparticles were fabricated using a one-pot supercritical CO2 gelling and drying method, followed by mild reduction under a N2 atmosphere. Electron microscopy images and N2 adsorption/desorption isotherms indicate the formation of 3D monolithic aerogels with a meso/macroporous morphology. A comprehensive evaluation of the synthesized photocatalyst was carried out with a focus on the target application: the photocatalytic production of H2 from methanol in aqueous media. The reaction conditions (water/methanol ratio, catalyst concentration), together with the aerogel composition (Pt/TiO2/rGO ratio) and architecture (size of the aerogel pieces), were the factors that varied in optimizing the process. These experimental parameters influenced the diffusion of the reactants/products inside the aerogel, the permeability of the porous structure, and the light-harvesting properties, all determined in this study towards maximizing H2 production. Using methanol as the sacrificial agent, the measured H2 production rate for the optimized system (18,800 µmolH2h-1gNPs-1) was remarkably higher than the values found in the literature for similar Pt/TiO2/rGO catalysts and reaction media (2000-10,000 µmolH2h-1gNPs-1).

Graphene Oxide/Polyethylenimine Aerogels for the Removal of Hg(II) from Water.

This article reports the synthesis of an aerogel involving reduced graphene oxide (rGO) and polyethylenimine (PEI), and describes its potential application as an effective sorbent to treat Hg(II) contaminated water. The rGO/PEI sorbent was synthetized using a supercritical CO2 method. N2 physisorption, electron microscopy, and elemental mapping were applied to visualize the meso/macroporous morphology formed by the supercritical drying. The advantages of the synthetized materials are highlighted with respect to the larger exposed GO surface for the PEI grafting of aerogels vs. cryogels, homogeneous distribution of the nitrogenated amino groups in the former and, finally, high Hg(II) sorption capacities. Sorption tests were performed starting from water solutions involving traces of Hg(II). Even though, the designed sorbent was able to eliminate almost all of the metal from the water phase, attaining in very short periods of time residual Hg(II) values as low as 3.5 µg L-1, which is close to the legal limits of drinking water of 1-2 µg L-1. rGO/PEI exhibited a remarkably high value for the maximum sorption capacity of Hg(II), in the order of 219 mg g-1. All of these factors indicate that the designed rGO/PEI aerogel can be considered as a promising candidate to treat Hg(II) contaminated wastewater.

The Role of Temperature on the Degree of End-Closing and Filling of Single-Walled Carbon Nanotubes.

Carbon nanotubes (CNTs), owing to their high surface area-to-volume ratio and hollow core, can be employed as hosts for adsorbed and/or encapsulated molecules. At high temperatures, the ends of CNTs close spontaneously, which is relevant for several applications, including catalysis, gas storage, and biomedical imaging and therapy. This study highlights the influence of the annealing temperature in the range between 400 and 1100 °C on the structure and morphology of single-walled CNTs. The nitrogen adsorption and density functional theory calculations indicate that the fraction of end-closed CNTs increases with temperature. Raman spectroscopy reveals that the thermal treatment does not alter the tubular structure. Insight is also provided into the efficacy of CNTs filling from the molten phase, depending on the annealing temperature. The CNTs are filled with europium (III) chloride and analyzed by using electron microscopy (scanning electron microscopy and high-resolution transmission electron microscopy) and energy-dispersive X-ray spectroscopy, confirming the presence of filling and closed ends. The filling yield increases with temperature, as determined by thermogravimetric analysis. The obtained results show that the apparent surface area of CNTs, fraction of closed ends, and amount of encapsulated payload can be tailored via annealing.

Broadening the scope of high structural dimensionality nanomaterials using pyridine-based curcuminoids.

We present a new heteroditopic ligand (3pyCCMoid) that contains the typical skeleton of a curcuminoid (CCMoid) decorated with two 3-pyridyl groups. The coordination of 3pyCCMoid with ZnII centres results in a set of novel coordination polymers (CPs) that display different architectures and dimensionalities (from 1D to 3D). Our work analyses how synthetic methods and slight changes in the reaction conditions affect the formation of the final materials. Great efforts have been devoted toward understanding the coordination entities that provide high dimensional systems, with emphasis on the characterization of 2D materials, including analyses of different types of substrates, stability and exfoliation in water. Here, we foresee the great use of CCMoids in the field of CPs and emphasize 3pyCCMoid as a new-born linker.

[Prevalence of SARS-CoV-2 coronavirus infection in patients and professional staff at a medium or long-stay hospital in Spain]. / Prevalencia de infección por coronavirus SARS-CoV-2 en pacientes y profesionales de un hospital de media y larga estancia en España.

BACKGROUND AND GOALS: The aim of the study is to know the prevalence of SARS-CoV-2 infection in patients and professional staff of a medium or long-stay hospital during the peak period of the pandemic in Spain, spring 2020. MATERIAL AND METHODS: At the end of February 2020, we developed at the hospital a strategy to diagnose the SARS-CoV-2 infection consisting of complementing the realization of PCR tests at real time with a quick technique of lateral flow immunochromatography to detect IgG and IgM antibodies against the virus. We also developed a protocol to realize those diagnostic tests and considered an infection (current or past) a positive result in any of the above tests. We included 524 participants in the study (230 patients and 294 hospital staff), and divided them into hospital patients and Hemodialysis outpatients. Furthermore, we divided the hospital staff into healthcare and non-healthcare staff. The documented period was from March, 20th to April, 21st, 2020. RESULTS: 26 out of 230 patients tested positive in any of the diagnostic techniques (PCR, antibodies IgG, IgM) with a 11.30% prevalence. According to patients groups, we got a 14.38% prevalence in hospital patients vs. 5.95% in outpatients, with a significantly higher risk in admitted patients after adjustment for age and gender (OR=3,309, 95%CI: 1,154-9,495). 24 out of 294 hospital staff tested positive in any of the diagnostic techniques, with a 8.16% prevalence. According to the groups, we got a 8.91% prevalence in healthcare staff vs. 4.26% in non-healthcare staff. Thus, we do not see any statistically significant differences between hospital staff and patients as far as prevalence is concerned (P=0,391), (OR=2,200, 95%CI: 0,500-9,689). CONCLUSIONS: The result of the study was a quite low prevalence rate of SARS-CoV-2 infection, in both patients and hospital staff, being the hospital patients' prevalence rate higher than the outpatients', and the healthcare staff higher than the non-healthcare's. Combining PCR tests (gold standard) with antibodies tests proved useful as a diagnostic strategy.

Prevalencia de infección por coronavirus SARS-CoV-2 en pacientes y profesionales de un hospital de media y larga estancia en España / Prevalence of SARS-CoV-2 coronavirus infection in patients and professional staff at a medium or long-stay hospital in Spain

ANTECEDENTES Y OBJETIVO: El objetivo de este estudio fue conocer la prevalencia de la infección por SARS-CoV-2 en pacientes y profesionales de un hospital de media y larga estancia en el periodo del pico de la pandemia en España en la primavera de 2020. MATERIAL Y MÉTODOS: A finales de febrero del 2020, se diseñó en el hospital una estrategia para el diagnóstico de la infección por SARS-CoV-2 consistente en complementar la realización de PCR a tiempo real con una técnica rápida de inmunocromatografía de flujo lateral para la detección de anticuerpos IgG e IgM frente al virus. Se protocolizó la realización de dichas pruebas diagnósticas y se consideró como infección (actual o pasada) un resultado positivo de alguna de ellas. Se incluyeron en el estudio a 524 participantes (230 pacientes y 294 profesionales). Los pacientes se agruparon en ingresados y en ambulatorios para terapia de hemodiálisis. Los trabajadores se agruparon en asistenciales y no asistenciales. El periodo que se documenta es el comprendido entre el 20 de marzo y el 21 de abril del 2020. RESULTADOS: En 26 de los 230 pacientes el resultado fue positivo en alguna de las técnicas, con una prevalencia del 11,30%. Por grupos, en ingresados fue del 14,38% frente al 5,95% de los ambulatorios (p = 0,055), siendo significativamente superior el riesgo en pacientes ingresados tras ajustar por sexo y edad (OR = 3,309; IC del 95%: 1,154-9,495). En 24 de los 294 profesionales el resultado fue positivo en alguna de las técnicas, con una prevalencia del 8,16%. Por grupos, en asistenciales fue del 8,91% frente al 4,26% de los no asistenciales (p = 0,391), OR ajustada = 2,502 (IC del 95%: 0,559-11,202). CONCLUSIONES: Se ha encontrado una tasa de prevalencia baja frente a SARS-CoV-2 tanto en pacientes como en profesionales. La prevalencia en pacientes hospitalizados es mayor que en ambulatorios, también es superior la prevalencia de sanitarios asistenciales respecto a los no asistenciales

BACKGROUND AND GOALS: The aim of the study is to know the prevalence of SARS-CoV-2 infection in patients and professional staff of a medium or long-stay hospital during the peak period of the pandemic in Spain, spring 2020. MATERIAL AND METHODS: At the end of February 2020, we developed at the hospital a strategy to diagnose the SARS-CoV-2 infection consisting of complementing the realization of PCR tests at real time with a quick technique of lateral flow immunochromatography to detect IgG and IgM antibodies against the virus. We also developed a protocol to realize those diagnostic tests and considered an infection (current or past) a positive result in any of the above tests. We included 524 participants in the study (230 patients and 294 hospital staff), and divided them into hospital patients and Hemodialysis outpatients. Furthermore, we divided the hospital staff into healthcare and non-healthcare staff. The documented period was from March, 20th to April, 21st, 2020. RESULTS: 26 out of 230 patients tested positive in any of the diagnostic techniques (PCR, antibodies IgG, IgM) with a 11.30% prevalence. According to patients groups, we got a 14.38% prevalence in hospital patients vs. 5.95% in outpatients, with a significantly higher risk in admitted patients after adjustment for age and gender (OR=3,309, 95%CI: 1,154-9,495). 24 out of 294 hospital staff tested positive in any of the diagnostic techniques, with a 8.16% prevalence. According to the groups, we got a 8.91% prevalence in healthcare staff vs. 4.26% in non-healthcare staff. Thus, we do not see any statistically significant differences between hospital staff and patients as far as prevalence is concerned (P=0,391), (OR=2,200, 95%CI: 0,500-9,689). CONCLUSIONS: The result of the study was a quite low prevalence rate of SARS-CoV-2 infection, in both patients and hospital staff, being the hospital patients' prevalence rate higher than the outpatients', and the healthcare staff higher than the non-healthcare's. Combining PCR tests (gold standard) with antibodies tests proved useful as a diagnostic strategy

Immobilization of BMP-2 and VEGF within Multilayered Polydopamine-Coated Scaffolds and the Resulting Osteogenic and Angiogenic Synergy of Co-Cultured Human Mesenchymal Stem Cells and Human Endothelial Progenitor Cells.

We have previously reported the fabrication of a polycaprolactone and hydroxyapatite composite scaffold incorporating growth factors to be used for bone regeneration. Two growth factors were incorporated employing a multilayered coating based on polydopamine (PDA). In particular, Bone morphogenetic protein-2 (BMP-2) was bound onto the inner PDA layer while vascular endothelial growth factor (VEGF) was immobilized onto the outer one. Herein, the in vitro release of both growth factors is evaluated. A fastest VEGF delivery followed by a slow and more sustained release of BMP-2 was demonstrated, thus fitting the needs for bone tissue engineering applications. Due to the relevance of the crosstalk between bone-promoting and vessel-forming cells during bone healing, the functionalized scaffolds are further assessed on a co-culture setup of human mesenchymal stem cells and human endothelial progenitor cells. Osteogenic and angiogenic gene expression analysis indicates a synergistic effect between the growth factor-loaded scaffolds and the co-culture conditions. Taken together, these results indicate that the developed scaffolds hold great potential as an efficient platform for bone-tissue applications.

Multi-layered polydopamine coatings for the immobilization of growth factors onto highly-interconnected and bimodal PCL/HA-based scaffolds.

For bone tissue engineering applications, scaffolds that mimic the porous structure of the extracellular matrix are highly desirable. Herein, we employ a PCL/HA-based scaffold with a double-scaled architecture of small pores coupled to larger ones. To improve the osteoinductivity of the scaffold, we incorporate two different growth factors via polydopamine (PDA) coating. As a first step, we identify the maximum amount of PDA that can be deposited onto the scaffold. Next, to allow for the deposition of a second PDA layer which, in turn, will allow to increase the loading of growth factors, we incorporate a dithiol connecting layer. The thiol groups covalently react with the first PDA coating through Michael addition while also allowing for the incorporation of a second PDA layer. We load the first and second PDA layers with bone morphogenic protein-2 (BMP2) and vascular endothelial growth factor (VEGF), respectively, and evaluate the osteogenic potential of the functionalised scaffold by cell viability, alkaline phosphatase activity and the expression of three different osteogenesis-related genes of pre-seeded human mesenchymal stem cells. Through these studies, we demonstrate that the osteogenic activity of the scaffolds loaded with both BMP2 and VEGF is greater than scaffolds loaded only with BMP2. Importantly, the osteoinductivity is higher when the scaffolds are loaded with BMP2 and VEGF in two different PDA layers. Taken together, these results indicate that the as-prepared scaffolds could be a useful construct for bone-tissue applications.

Bacterial cellulose/graphene oxide aerogels with enhanced dimensional and thermal stability.

We present a novel method for processing bacterial cellulose/graphene oxide (BC/GO) aerogels with multifunctional properties. The addition of a small amount of dimethyl sulfoxide (DMSO) to the aqueous dispersion of the nanomaterials during the gelification process affected the water freezing temperature of the system and thereby affecting the porous structure of the aerogel obtained after liophilization. The possibility to obtain small and elongated pore with axial orientation allowed a significant improvement of the structural stability of the aerogels. Moreover, the aerogels reduction by thermal treatment with ammonia gas induced crosslinking between the different nanophases, thus given an incremental factor for the mechanical performance of the aerogels under harsh conditions. The resulting aerogels also showed significant improvements in terms of thermal stability and electrical conductivity. These multifunctional BC/GO aerogels present high potential as sustainable and ecological alternative materials for lightweight packaging, filters for atmosphere and water treatment, or energy applications.

Single molecule magnets of cobalt and zinc homo- and heterometallic coordination polymers prepared by a one-step synthetic procedure.

The synthesis of 1D cobalt and zinc monometallic and heterometallic coordination polymers (CPs) was carried out applying one-pot synthetic methods by using either supercritical carbon dioxide or ethanol as the solvent. A collection of four 1D CPs were thus obtained by the combination of a metal (or a mixture of metals) with the linker 1,4-bis(4-pyridylmethyl)benzene. The used metallic complexes were zinc and cobalt hexafluoroacetylacetonate, which can easily incorporate pyridine ligands in the coordination sphere of the metal centre. Independently of the used solvent, the precipitated phases involving Zn(ii), i.e., homometallic CP of Zn(ii) and bimetallic CP of Zn(ii)/Co(ii), were isostructural. Contrarily, homometallic CPs of Co(ii) were precipitated as an isostructural phase of Zn(ii) or with a different structure, depending on the used solvent. All the structures were resolved by XRD using synchrotron radiation. In addition, the magnetic properties of the new CPs involving Co(ii) were studied. Remarkably, at low temperatures with the application of an external field, they acted as field-induced single molecule magnets.

Preparation and Characterization of Graphene Oxide Aerogels: Exploring the Limits of Supercritical CO2 Fabrication Methods.

The supercritical carbon dioxide (scCO2 ) synthesis of non-reduced graphene oxide (GO) aerogels from dispersions of GO in ethanol is here reported as a low-cost, efficient, and environmentally friendly process. The preparation is carried out under the mild conditions of 333 K and 20 MPa. The high aspect ratio of the used GO sheets (ca. 30 µm lateral dimensions) allowed the preparation of aerogel monoliths by simultaneous scCO2 gelation and drying. Solid-state characterization results indicate that a thermally-stable mesoporous non-reduced GO aerogel was obtained by using the supercritical procedure, keeping most of the surface oxygenated groups on the GO sheets, thus, facilitating further functionalization. Moreover, the monoliths have a very low density, high specific surface area, and excellent mechanical integrity; characteristics which rival those of most light-weight reduced graphene aerogels reported in the literature.

An Unprecedented Stimuli-Controlled Single-Crystal Reversible Phase Transition of a Metal-Organic Framework and Its Application to a Novel Method of Guest Encapsulation.

The flexibility and unexpected dynamic behavior of a third-generation metal-organic framework are described for the first time. The synthetic strategy is based on the flexibility and spherical shape of dipyridyl-based carborane linkers that act as pillars between rigid Co/BTB (BTB: 1,3,5-benzenetricarboxylate) layers, providing a 3D porous structure (1). A phase transition of the solid can be induced to generate a new, nonporous 2D structure (2) without any loss of the carborane linkers. The structural transformation is visualized by snapshots of the multistep single-crystal-to-single-crystal transformation by single-crystal and powder X-ray diffraction. Poor hydrogen bond acceptors such as MeOH, CHCl3 or supercritical CO2 induce such a 3D to 2D transformation. Remarkably, the transformation is reversible and the 2D phase 2 is further converted back into 1 by heating in dimethylformamide. The energy requirements involved in such processes are investigated using periodic density functional theory calculations. As a proof of concept for potential applications, encapsulation of C60 is achieved by trapping this molecule during the reversible 2D to 3D phase transition, whereas no adsorption is observed by straight solvent diffusion into the pores of the 3D phase.

Modulating p-hydroxycinnamate behavior as a ditopic linker or photoacid in copper(ii) complexes with an auxiliary pyridine ligand.

The reaction of copper(ii) acetate monohydrate with p-hydroxycinnamic acid (HpOHcinn) and different pyridine derivatives (4-tert-butylpyridine, 4-tBupy; 4-acetylpyridine, 4-Acpy; 3-phenylpyridine, 3-Phpy; 4-phenylpyridine, 4-Phpy) was essayed in methanol solvent at room temperature. The crystal structures of the resulting compounds were elucidated. Their analysis shows that the choice of pyridine ligands determines different coordination modes of the pOHcinn ligand and the Cu(ii) coordination, nuclearity and geometry. The pOHcinn acts as a monodentate carboxylate ligand in combination with 4-tBupy or 4-Phpy, yielding monomers and dimers, associated by hydrogen bonds into supramolecular networks in which the phenol group plays a key role. Conversely, in combination with 4-Acpy or 3-Phpy, the phenol group coordinates directly to the Cu(ii), acting as a ditopic ligand and yielding 2D coordination polymers. The compound containing 3-Phpy shows interesting MeOH-H2O reversible exchange behavior. Not only has the pyridine auxiliary ligand had a tremendous effect on the coordination mode of pOHcinn, but also its reactivity is influenced. Particularly, in the case of the compound containing 4-Phpy, it undergoes a photoinduced process, in which the phenol group deprotonates and coordinates to Cu(ii) as a phenoxy ligand. This yields a coordination polymer in which two different dimers alternate, bridged by the resulting pOcinn ligand. The magneto-structural correlation of this compound is also discussed.

Synthetic scaffolds with full pore interconnectivity for bone regeneration prepared by supercritical foaming using advanced biofunctional plasticizers.

Supercritical foaming allows for the solvent-free processing of synthetic scaffolds for bone regeneration. However, the control on the pore interconnectivity and throat pore size with this technique still needs to be improved. The use of plasticizers may help overcome these limitations. Eugenol, a GRAS natural compound extracted from plants, is proposed in this work as an advanced plasticizer with bioactive properties. Eugenol-containing poly(ε-caprolactone) (PCL) scaffolds were obtained by supercritical foaming (20.0 MPa, 45 °C, 17 h) followed by a one or a two-step depressurization profile. The effects of the eugenol content and the depressurization profile on the porous structure of the material and the physicochemical properties of the scaffold were evaluated. The combination of both processing parameters was successful to simultaneously tune the pore interconnectivity and throat sizes to allow mesenchymal stem cells infiltration. Scaffolds with eugenol were cytocompatible, presented antimicrobial activity preventing the attachment of Gram positive (S. aureus, S. epidermidis) bacteria and showed good tissue integration.

PCL-HA microscaffolds for in vitro modular bone tissue engineering.

The evolution of microscaffolds and bone-bioactive surfaces is a pivotal point in modular bone tissue engineering. In this study, the design and fabrication of porous polycaprolactone (PCL) microscaffolds functionalized with hydroxyapatite (HA) nanoparticles by means of a bio-safe and versatile thermally-induced phase separation process is reported. The ability of the as-prepared nanocomposite microscaffolds to support the adhesion, growth and osteogenic differentiation of human mesenchymal stem cells (hMSCs) in standard and osteogenic media and using dynamic seeding/culture conditions was investigated. The obtained results demonstrated that the PCL-HA nanocomposite microparticles had an enhanced interaction with hMSCs and induced their osteogenic differentiation, even without the exogenous addition of osteogenic factors. In particular, calcium deposition, alizarin red assay, histological analysis, osteogenic gene expression and collagen I secretion were assessed. The results of these tests demonstrated the formation of bone microtissue precursors after 28 days of dynamic culture. These findings suggest that PCL-HA nanocomposite microparticles represent an excellent platform for in vitro modular bone tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd.

PCL foamed scaffolds loaded with 5-fluorouracil anti-cancer drug prepared by an eco-friendly route.

This study describes a new preparation method, which combines freeze drying and supercritical CO2 foaming approaches, for the preparation of drug delivery scaffolds of polycaprolactone loaded with 5-fluorouracil, an anti-cancer drug, with low solubility in scCO2. It is a principal objective of this work to design a scCO2 strategy to reduce 5-Fu solubility limitations in its homogeneous distribution into a PCL scaffold through the design of an innovative processing method. The design of this process is considered valuable for the development of clean technology in pharmacy and medicine, since most of the active agents have a null solubility in scCO2·Supercritical CO2 is used as a blowing agent to induce polymer foaming by means of the low temperature pressure quench process. The resulting samples have been prepared under different operational conditions focused on enhancing the performance of the release process. In this case, design of experiments (DOE) was considered for a more comprehensive and systematic optimization of the product. In particular, drug amount, equals to 4.8 or 9.1wt%, process temperature, of 45 or 50°C and depressurization rate, equals to 0.1MPas-1 or 2MPas-1 were selected as the factors to be investigated by a three-factor at two-level full factorial design. Samples were characterized to establish porosity data, drug loading percentage and, especially, release profile chromatographically monitored. Results from DOE have concluded which are the best samples providing a sustained drug release for several days, which may be of great interest to develop materials for tissue engineering and sustained release applications.

Mechanism of drug release from silica-gelatin aerogel-Relationship between matrix structure and release kinetics.

Specific features of a silica-gelatin aerogel (3 wt.% gelatin content) in relation to drug delivery has been studied. It was confirmed that the release of both ibuprofen (IBU) and ketoprofen (KET) is about tenfold faster from loaded silica-gelatin aerogel than from pure silica aerogel, although the two matrices are structurally very similar. The main goal of the study was to understand the mechanistic background of the striking difference between the delivery properties of these closely related porous materials. Hydrated and dispersed silica-gelatin aerogel has been characterized by NMR cryoporometry, diffusiometry and relaxometry. The pore structure of the silica aerogel remains intact when it disintegrates in water. In contrast, dispersed silica-gelatin aerogel develops a strong hydration sphere, which reshapes the pore walls and deforms the pore structure. The drug release kinetics was studied on a few minutes time scale with 1s time resolution. Simultaneous evaluation of all relevant kinetic and structural information confirmed that strong hydration of the silica-gelatin skeleton facilitates the rapid desorption and dissolution of the drugs from the loaded aerogel. Such a driving force is not operative in pure silica aerogels.

Utilidad del índice PROFUND para predecir la mortalidad a los 4 años en pacientes pluripatológicos / Reliability of the PROFUND index to predict 4-year mortality in polypathological patients

Objetivo: Determinar la validez del índice PROFUND para establecer el riesgo de muerte global a los 4 años en pacientes pluripatológicos. Pacientes y métodos: Estudio de cohortes (Medicina Interna y Geriatría) prospectivo y multicéntrico. Se incluyeron pacientes pluripatológicos ingresados entre el 1 de marzo y el 30 de junio de 2011. Se recogieron datos de edad, sexo, si vivían en el domicilio o en una residencia, categorías de pluripatología, índices de Charlson, Lawton-Brody y Barthel, cuestionario de Pfeiffer, escala sociofamiliar de Gijón, delirium, número de fármacos, hemoglobina, creatinina e índice PROFUND. Se realizó un seguimiento durante 4 años. Resultados: Se incluyeron 441 pacientes, 324 de Medicina Interna y 117 de Geriatría, con una edad media de 80,9 (8,7) años, y 245 (55,6%) eran mujeres. Las enfermedades cardiacas (62,7%), neurológicas (41,4%) y respiratorias (37,3%) fueron las más frecuentes. Los pacientes de Geriatría eran de más edad, más dependientes y con más deterioro cognitivo. Al cabo de 4 años habían fallecido 335 (76%) pacientes. Los factores asociados de forma independiente con la mortalidad fueron la edad, la disnea, el índice de Barthel<60, el delirium, las neoplasias avanzadas y haber ingresado 4 o más veces en el último año. El rendimiento del índice PROFUND fue bueno en los pacientes de Medicina Interna y malo en los de Geriatría (0,748, IC 95% 0,689-0,806, p<0,001, y 0,517, IC 95% 0,369-0,666, p=0,818, respectivamente). Conclusiones: El índice PROFUND es útil para predecir la mortalidad global a largo plazo en los pacientes pluripatológicos de Medicina Interna, pero no en los de Geriatría (AU)

Objective: To determine the usefullness of the PROFUND index to assess the risk of global death after 4 years in polypathological patients. Patients and methods: Multicenter prospective cohort (Internal Medicine and Geriatrics) study. Polypathological patients admitted between March 1st and June 30th 2011 were included. For each patient, data concerning age, sex, living at home or in a nursing residence, polypathology categories, Charlson, Barthel and Lawton-Brody indexes, Pfeiffer questionnaire, socio-familial Gijon scale,delirium, number of drugs, hemoglobin and creatinine values were gathered, and the PROFUND index was calculated. The follow-up lasted 4 years. Results: We included 441 patients, 324 from Internal Medicine and 117 from Geriatrics, with a mean age of 80.9 (8.7) years. Of them, 245 (55.6%) were women. Heart (62.7%), neurological (41.4%) and respiratory (37.3%) diseases were the most frequent. Geriatrics inpatients were older and more dependants and presented greater cognitive deterioration. After 4 years, 335 (76%) patients died. Mortality was associated with age, dyspnoea, Barthel index<60,delirium, advanced neoplasia and≥4 admissions in the last year. The area under the curve of the PROFUND index was 0.748, 95% CI 0.689-0.806, P<.001 in Internal Medicine and 0.517, 95% CI 0.369-0.666, P=.818 in Geriatrics patients, respectively. Conclusions: The PROFUND index is a reliable tool for predicting long-term global mortality in polypathological patients from Internal Medicine but not from Geriatrics departments (AU)