Developing an improved optical biosensing system based on gold nanoparticles acting as interferometric enhancers in Lactoferrin detection.

We report for the first time the whole development of a biosensing system based on the Interferometric Optical Detection Method (IODM) enriched with gold nanoparticles (AuNPs), acting as interferometric enhancers for improving the performance of immunoassays. For this purpose, the Lactoferrin sandwich immunoassay model was employed. We describe in detail the entire value chain from the AuNPs production, its functionalization, and characterization with anti-Lactoferrin (anti-LF), the biosensing response of these conjugates as well as their corresponding calculation of the kinetic constants, performance comparison of the readout interferometric signals versus Scanning Electron Microscopy (SEM) and the percentage of the sensing surface covered. Finally, a Lactoferrin sandwich immunoassay was carried out and correlated with Enzyme-Linked ImmunoSorbent Assay (ELISA), and the Limit of Detection and sensitivity figures were obtained. As a result, we demonstrate how the AuNPs act as interferometric amplifiers of the IODM for improving the biosensing response, opening the possibility of being applied in multiple biological detection applications.

Erratum: Canle, M., et al. Improved Photocatalyzed Degradation of Phenol, as a Model Pollutant, over Metal-Impregnated Nanosized TiO2. Nanomaterials 2020, 10, 996.

The authors wish to make the following corrections to this paper: [...].

Improved Photocatalyzed Degradation of Phenol, as a Model Pollutant, over Metal-Impregnated Nanosized TiO2.

Photocatalyzed degradation of phenol in aqueous solution over surface impregnated TiO2 (M = Cu, Cr, V) under UV-Vis (366 nm) and UV (254 nm) irradiation is described. Nanosized photocatalyts were prepared from TiO2-P25 by wet impregnation, and characterized by X-ray diffraction, X-ray fluorescence, transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy, Raman spectroscopy, and adsorption studies. No oxide phases of the metal dopants were found, although their presence in the TiO2-P25 lattice induces tensile strain in Cu-impregnated TiO2-P25, whereas compressive strain in Cr- and V-impregnated TiO2-P25. Experimental evidences support chemical and mechanical stability of the photocatalysts. Type IV N2 adsorption-desorption isotherms, with a small H3 loop near the maximum relative pressure were observed. Metal surface impregnated photocatalysts are mesoporous with a similar surface roughness, and a narrow pore distribution around ca. 25 Å. They were chemically stable, showing no metal lixiviation. Their photocatalytic activity was followed by UV-Vis spectroscopy and HPLC-UV. A first order kinetic model appropriately fitted the experimental data. The fastest phenol degradation was obtained with M (0.1%)/TiO2-P25, the reactivity order being Cu > V >> Cr > TiO2-P25 under 366 nm irradiation, while TiO2-P25 > Cu > V > Cr, when using 254 nm radiation. TOC removal under 366 nm irradiation for 300 min showed almost quantitative mineralization for all tested materials, while 254 nm irradiation for 60 min led to maximal TOC removal (ca. 30%). Photoproducts and intermediate photoproducts were identified by HPLC-MS, and appropriate reaction pathways are proposed. The energy efficiency of the process was analysed, showing UV lamps are superior to UVA lamps, and that the efficiency of the surface impregnated catalyst varies in the order Cu > V > Cr.

Siloxane-inorganic chemical crosslinking of hyaluronic acid - based hybrid hydrogels: Structural characterization.

HA-based hybrid hydrogels were successfully developed. The polysaccharide (HA) chains were chemically modified and hybridized via amidation of their carboxylic groups with aminosilane molecules. HA-polysaccharide chains were crosslinked by a 3D siloxane organic-inorganic matrix via sol-gel. The novel inorganic crosslinking network (PDMS-SiO2) provided to sodium hyaluronate (HA) strong chemical bonds, giving restriction to their natural hydrophilicity and stiffness to its structure (improved rheological properties). It was observed that synthesis conditions such as starting HA concentration solution and temperature determined gelling times, efficiency in the polysaccharide chemical modification and in crosslinking hydrolysis-condensation reactions, resulting in the siloxane organic-inorganic matrix. Drying processes influenced crosslinking in HA hybrid hydrogels, either by enhancing polycondensation reactions or inhibiting them. Room temperature-drying produced more densified hybrid structures. Freeze-drying increased porosity and surface hydroxyl groups (-OH) resulting in more Q3 structural units. 60 °C-drying boosted polycondensation of monodendate structural units, enhancing the formation of hybrid D-Q bonds.

Diferencias de edad en el rendimiento de golpeo de balón en fútbol / Age-Related Differences in Kicking Performance in Soccer

El objetivo de este estudio fue examinar la evolución del rendimiento máximo de golpeo de balón a lo largo de la edad en futbolistas jóvenes de élite. Un total de 175 fueron divididos en 11 grupos edad (U-9 hasta U-19), además del equipo filial del club (U-23). Se registró la velocidad máxima de golpeo con la pierna dominante y no dominante mediante radar. El déficit de golpeo fue calculado para comparar el rendimiento entre ambas piernas. La velocidad máxima de golpeo aumenta progresivamente de forma significativa desde U-9 hasta U-16 con la pierna dominante y hasta U-18 con la no dominante, y sigue aumentando de forma no significativa hasta U-23. La etapa con mayor incremento de la velocidad de golpeo fue entre U-13 y U-16. Existe un déficit de golpeo con la pierna no dominante y sus valores permanecen estables (9.43%-18.18%) sin cambios significativos desde U-9 hasta U-23

The purpose of this current study was to examine the age-related differences in kicking performance with both legs in 175 youth soccer players. Players from the development programme of a professional club were grouped according to their respective under-age team (U-9 to U-18), in addition to the club's second team (U-23). Maximal kicking velocity with the preferred and non-preferred leg was recorded using a Doppler radar gun. Kicking deficit was calculated to compare side-to-side performance. Maximal kicking velocity improved progressively from the U-9 to U-16 age groups for the preferred leg and from U-16 to U-18 for the non-preferred leg, and continued to improve moderately but non-statistically significant until U-23. The stage of greatest kicking velocity development was between 13 and 16 years of age. There is a kicking deficit with the non-preferred leg and its values remain steady (9.43%-18.18%) without significant changes in players from U-9 to U-23 categories

Decoupling the shape parameter to assess gold nanorod uptake by mammalian cells.

The impact of nanoparticles (NPs) upon biological systems can be fundamentally associated with their physicochemical parameters. A further often-stated tenet is the importance of NP shape on rates of endocytosis. However, given the convoluted parameters concerning the NP-cell interaction, it is experimentally challenging to attribute any findings to shape alone. Herein we demonstrate that shape, below a certain limit, which is specific to nanomedicine, is not important for the endocytosis of spherocylinders by either epithelial or macrophage cells in vitro. Through a systematic approach, we reshaped a single batch of gold nanorods into different aspect ratios resulting in near-spheres and studied their cytotoxicity, (pro-)inflammatory status, and endocytosis/exocytosis. It was found that on a length scale of ∼10-90 nm and at aspect ratios less than 5, NP shape has little impact upon their entry into either macrophages or epithelial cells. Conversely, nanorods with an aspect ratio above 5 were preferentially endocytosed by epithelial cells, whereas there was a lack of shape dependent uptake following exposure to macrophages in vitro. These findings have implications both in the understanding of nanoparticle reshaping mechanisms, as well as in the future rational design of nanomaterials for biomedical applications.

Distribution of Silica-Coated Silver/Gold Nanostars in Soft- and Hardwood Applying SERS-Based Imaging.

Nanoparticles (NPs) in aqueous suspension have just begun to be exploited for the preservative treatment of wood. However, at present, there is very little information available on the distribution of NPs in wood after impregnation, due to associated analytical challenges. In this study, we present the detection of model NPs in softwood and hardwood by surface-enhanced Raman spectroscopy (SERS). SERS is a highly sensitive analytical method requiring no fluorescent labeling. The NP distribution after impregnation is evaluated with one representative species of the two wood types. To show the feasibility of the method, we prepared SERS-active Au/Ag nanostars coated with silica to act as a model NP system. We show herein that NPs can be imaged in very low quantities in both wood types without any matrix interactions. The presence of the NPs in the wood was confirmed by scanning electron microscopy (SEM) imaging and energy dispersive X-ray analysis (EDX). The fast detection of NPs in a complex matrix, without complicated sample preparation, marks a huge step forward in the development and application of nanotechnology for wood preservation and the quest to optimize the properties of one of the world's most important raw materials.

Characterizing nanoparticles in complex biological media and physiological fluids with depolarized dynamic light scattering.

Light scattering is one of the few techniques available to adequately characterize suspended nanoparticles (NPs) in real time and in situ. However, when it comes to NPs in multicomponent and optically complex aqueous matrices - such as biological media and physiological fluids - light scattering suffers from lack of selectivity, as distinguishing the relevant optical signals from the irrelevant ones is very challenging. We meet this challenge by building on depolarized scattering: Unwanted signals from the matrix are completely suppressed. This approach yields information with an unprecedented signal-to-noise ratio in favour of the NPs and NP-biomolecule corona complexes, which in turn opens the frontier to scattering-based studies addressing the behaviour of NPs in complex physiological/biological fluids.

The synthesis and characterisation of strontium and calcium folates with potential osteogenic activity.

Compounds having the general formula MFO·4H2O where M = Ca or Sr and FO = a folate anion were prepared and their structure and physico-chemical properties were determined by elemental and thermal TGA, DSC analysis, FTIR, and EDAX spectroscopies and DRX. The results indicate that the two compounds form stable structures where folic acid acts as a self-bridging ligand via two bidentate carboxylate groups. Moreover the two compounds showed a low toxicity in vitro response as h-osteoblast cell viability was not negatively affected by the presence of folate derivatives within the range of 0.063-0.5 mg ml-1. The results also indicate that the folate derivatives that are formed overcome the toxic effects related to free Sr2+ ions. The range of maximum cell viability corresponding with a concentration of SrFO falls within the in vitro physiologically active range for strontium while within the same range the strontium derivative showed a potential osteogenic activity as indicated by the overexpression of ALP activity.

In vitro dosimetry of agglomerates.

Agglomeration of nanoparticles in biological fluids is a pervasive phenomenon that leads to difficulty in the interpretation of results from in vitro exposure, primarily due to differing particokinetics of agglomerates to nanoparticles. Therefore, well-defined small agglomerates were designed that possessed different particokinetic profiles, and their cellular uptake was compared to a computational model of dosimetry. The approach used here paves the way for a better understanding of the impact of agglomeration on the nanoparticle-cell interaction.

Tratamiento de la trombosis venosa profunda asociada a agenesia de vena cava inferior. Revisión de las anomalías de vena cava inferior / Treatment of deep venous thrombosis associated with inferior vena cava agenesis. A review of inferior vena cava variants

La complejidad de la embriología de la vena cava inferior, con numerosas anastomosis entre pares de venas, puede conducir a multitud de variantes anatómicas. En la población general la agenesia de la vena cava inferior constituye una malformación poco frecuente (0,07%), pero su presencia representa el 5-9,5% de las trombosis venosas profundas idiopáticas en pacientes menores de 30 años y su tratamiento continúa siendo un tema controvertido(AU)

The development of the inferior vena cava is a complex embryological process, with numerous anastomoses among pairs of veins, which may result in many anatomic variants. In the general population, the absence of inferior vena cava is a rare anomaly (0.07%), but this represents 5-9.5% of idiopathic deep venous thrombosis in patients under 30 years-old and its treatment options remain (AU)

Actualización en anemia y terapia transfusional / Anemia and transfusion therapy: an update

La anemia representa una de las patologías más prevalentes en la población general y constituye una entidad extremadamente frecuente en pacientes médicos y quirúrgicos de todas las especialidades. Una correcta valoración de su impacto y de las posibilidades terapéuticas resulta crucial. La transfusión de sangre alogénica representa una medida eficaz en el manejo de la anemia, pero no está exenta de importantes complicaciones. Es responsabilidad del clínico conocer y sopesar todas las alternativas disponibles para el manejo global de la anemia. Transfusiones sanguíneas, agentes estimuladores de la eritropoyesis, ferroterapia (oral y endovenosa) y otras alternativas terapéuticas han de ser empleadas de forma racional y ajustándonos a la evidencia clínica disponible hasta la fecha. El presente artículo de revisión resume algunas características epidemiológicas de la anemia, su valoración clínica y las principales alternativas terapéuticas a la luz de los conocimientos actuales, con especial énfasis en el paciente crítico (AU)

Anemia is one of the most prevalent diseases in the general population and is a very frequently found condition in medical and surgical patients in all medical specialties. A good evaluation of its clinical impact and its therapeutic possibilities is essential. Allogenic blood transfusion is a useful procedure in anemia management, although it has important adverse effects. It is the responsibility of the clinician to know and to take into account all the available alternatives for the treatment of anemia. Blood transfusions, erythropoiesis-stimulating agents, iron therapy (oral and endovenous) and other therapeutic alternatives must be rationally used, in accordance with the currently available clinical evidence. This review article summarizes some epidemiological characteristics of anemia, its clinical evaluation and the main therapeutic possibilities based on the present knowledge, placing special emphasis on the critically ill patient (AU)

[Anemia and transfusion therapy: an update]. / Actualización en anemia y terapia transfusional.

Anemia is one of the most prevalent diseases in the general population and is a very frequently found condition in medical and surgical patients in all medical specialties. A good evaluation of its clinical impact and its therapeutic possibilities is essential. Allogenic blood transfusion is a useful procedure in anemia management, although it has important adverse effects. It is the responsibility of the clinician to know and to take into account all the available alternatives for the treatment of anemia. Blood transfusions, erythropoiesis-stimulating agents, iron therapy (oral and endovenous) and other therapeutic alternatives must be rationally used, in accordance with the currently available clinical evidence. This review article summarizes some epidemiological characteristics of anemia, its clinical evaluation and the main therapeutic possibilities based on the present knowledge, placing special emphasis on the critically ill patient.

Field gradient imaging of nanoparticle systems: analysis of geometry and surface coating effects.

In this work we compare the standard imaging of various types of nanoparticles deposited on surfaces by atomic force microscopy (AFM) with a complementary analysis of the same samples by either electrostatic force microscopy (EFM) or magnetic force microscopy (MFM). Experiments were carried out on gold nanoparticles (decahedrons and stars) and two different iron oxide systems: goethite (alpha-FeOOH) and hematite (alpha-Fe(2)O(3)). Regardless of the particular geometry, the EFM signal appears to be stronger on edges or tips of pure gold nanoparticles. Both EFM and MFM experiments were also carried out on iron oxide particles. Apart from the structural analysis, we analyzed the influence of a shell layer deposited on the gold and iron oxide particles, the shell being amorphous SiO(2). Although the silica layer was found to have an insulating effect around the particles, in all cases EFM/MFM measurements could still be performed by the proper choice of the scan lift height (with an eventual slight increase of the sample bias, where applicable).

Synthesis, characterization, bioactivity and biocompatibility of nanostructured materials based on the wollastonite-poly(ethylmethacrylate-co-vinylpyrrolidone) system.

Composite materials are very promising biomaterials for hard tissue augmentation. The approach assayed in this work involves the manufacturing of a composite made of a bioactive ceramic, natural wollastonite (W) and a nanostructured copolymer of ethylmethacrylate (EMA) and vinylpyrrolidone (VP) to yield a bioresorbable and biocompatible VP-EMA copolymer. A bulk polymerization was induced thermally at 50 degrees C, using 1 wt % azobis(isobutyronitrile) (AIBN) as free-radical initiator. Structural characterization, compressive strength, flexural strength (FS), degradation, bioactivity, and biocompatibility were evaluated in specimens with a 60/40 VP/EMA ratio and ceramic content in the range 0-60%. A good integration between phases was achieved. Greater compression and FS, in comparison with the pure copolymer specimens was obtained only when the ceramic load got up to 60% of the total weight. The soaking in NaCl solution resulted in the initial swelling of the specimens tested. The maximum swelling was reached after 2-3 h of immersion and it was significantly greater for lower ceramic loads. This result makes the polymer component the main responsible for the interactions with the media. After soaking in SBF, microdomains segregation can be observed in the polymer component that can be related with a dramatic difference in the reactivity of both monomers in free radical polymerization, whereas the formation of an apatite-like layer on the W surfaces can be observed. Biocompatibility in vitro studies showed the absence of cytotoxicity of all formulations. The cells were able to adhere on the polystyrene negative control and on specimens containing 60 wt % wollastonite forming a monolayer and showing a normal morphology. However, a low cellular growth was observed.

Síndrome compartimental abdominal en el postoperatorio de un paciente con aneurisma de aorta abdominal infrarrenal fisurado. Caso clínico y revisión de la bibliografía / Abdominal compartment syndrome in the post-operative period in a patient with a fissured aneurysm in the infrarenal abdominal aorta. A case report and review of the literature

Introducción. El síndrome compartimental abdominal (SCA) representa una entidad clínica caracterizada por un aumento de la presión intraabdominal con potencial para provocar, si no se diagnostica y se corrige a tiempo, fallo multiorgánico progresivo y la muerte del paciente. En nuestra especialidad, el paradigma sería los enfermos con un aneurisma de aorta abdominal fisurado y tratados tanto con cirugía abierta convencional, como mediante técnicas endovasculares. Caso clínico. Varón de 79 años con factores de riesgo vascular habituales, que acudió a Urgencias por un cuadro de dolor lumbar con masa abdominal pulsátil en la exploración. Tras la realización de una tomografía axial computarizada, que confirmó el diagnóstico y descartó la terapéutica endovascular, fue intervenido mediante cirugía abierta, en la que se realizó una exclusión del aneurisma y una derivación aortobifemoral. En el postoperatorio precoz presentó deterioro clínico progresivo, oligoanuria y distensión abdominal grave por lo que, tras descartar otras causas de fallo multiorgánico, se realizó medición de la presión intravesical ante la sospecha de posible SCA. Tras confirmar la situación de hiperpresión intraabdominal fue reintervenido para realizar una laparotomía descompresiva. En la revisión de la bibliografía se discute la fisiopatología, los métodos diagnósticos y el tratamiento del SCA. Conclusión. Existe un grupo de pacientes en los que la identificación de las situaciones de riesgo de desarrollar un SCA resulta vital para evitar, mediante una intervención precoz, un desenlace fatal hacia el fallo multiorgánico y el fallecimiento

Introduction. Abdominal compartment syndrome (ACS) is a clinical entity characterised by an increase in the intra-abdominal pressure which can potentially lead to progressive multiple organ failure and the death of the patient, if it is not diagnosed and corrected in time. In our speciality, the paradigm would be patients with a fissured abdominal aortic aneurysm who have been treated with both conventional open surgery and by means of endovascular techniques. Case report. A 79-year-old male with the usual vascular risk factors, who visited the Emergency Department because of symptoms consisting in lower back pain and an abdominal pulsatile mass that was found in the examination. Following a computerised axial tomography scan, which confirmed the diagnosis and precluded the possibility of endovascular therapy, the patient was submitted to open surgery, which involved exclusion of the aneurysm and an aortobifemoral bypass. During the early phase of the post-operative period the patient showed progressive clinical deterioration, oligoanuria and severe abdominal distension. In consequence, after ruling out other causes of multiple organ failure and with the suspicion of possible ACS, the intravesical pressure was measured. After confirming the existence of high pressure within the abdomen, a second operation was performed to carry out a decompressive laparotomy. In the review of the literature, the pathophysiology, diagnostic methods and treatment of ACS are discussed. Conclusions. There is a group of patients in whom the identification of situations of higher risk of developing ACS is essential so that an early intervention can prevent a fatal outcome that leads to multiple organ failure and death

Acrylic injectable and self-curing formulations for the local release of bisphosphonates in bone tissue.

Two bisphosphonates (BPs), namely 1-hydroxy-2-[4-aminophenyl]ethane-1,1-diphosphonic acid (APBP) and 1-hydroxy-2-[3-indolyl]ethane-1,1-diphosphonic acid (IBP), have been synthesized and incorporated to acrylic injectable and self-curing formulations. Alendronic acid monosodium trihydrated salt (ALN) containing cement was formulated as control. These systems have potential applications in low density hard tissues affected by ailments characterized by a high osteoclastic resorption, i.e. osteoporosis and osteolysis. Values of curing parameters of APBP and IBP were acceptable to obtain pastes with enough fluency to be injected through a biopsy needle into the bone cavity. Working times ranged between 8 and 15 min and maximum temperature was around 50 degrees C. Cured systems stored for a month in synthetic body fluid had compressive strengths between 90 and 96 MPa and modulus between 1.2 and 1.3 GPa, which suggest mechanical stabilization after setting and in the short time. BPs were released in PBS at an initial rate depending on the corresponding chemical structure in the order ALN > APBP > IBP to give final concentrations in PBS of 2.21, 0.44, and 0.19 mol/mL for ALN, APBP, and IBP, respectively. Cytotoxicities of bisphosphonates were evaluated, IC(50) values being in the order APBP > ALN > IBP. Absence of cytotoxicity coming from leachables of the cured systems was observed in all cases independently of the BP. An improved cell growth and proliferation for the systems loaded with APBP and IBP compared with that loaded with ALN was observed, as assessed by measuring cell adhesion and proliferation, and total DNA content.

Influence of ferrous iron incorporation on the structure of hydroxyapatite.

Iron is a vital element of cellular function within the body. High concentrations of iron can be found in the kidneys and the circulatory system. In bones and teeth it is present as a trace element. The use of iron-based compounds in combination with hydroxyapatite offers a new alternative for prosthetic devices. This work investigates the synthesis and processing of iron containing apatites as a possible new type of ceramic for biomedical devices. Stoichiometric and calcium deficient iron containing apatites were synthesized by a wet chemical reaction with di-ammonium-hydrogen-phosphate, calcium nitrate and a ferrous iron nitrate solution. A secondary phase of tri-calcium-phosphate (TCP) was observed after heat treatment of iron containing, calcium deficient, hydroxyapatite. The apatite structure was maintained after heat treatment of stoichiometric apatite, synthesized in the presence of iron. Sintering in air produced oxidation of Fe2+ to Fe3+, resulting in the formation of hematite as a secondary phase. The introduction of iron into the synthesis of hydroxyapatite causes: (i) an increase of the a-lattice parameter after synthesis and heat treatment in air; (ii) an increase in the c-lattice parameter after sintering in air.

Studies on calcium deficient apatites structure by means of MAS-NMR spectroscopy.

The development of synthetic apatites that replicate the features and properties of the contained in natural tissues will help to diminish the misfit between artificial implants and natural hostesses but the structure of these compounds is still under discussion. The variability in Ca/P ratio of calcium deficient apatites has been explained through different models: surface adsorption, lattice substitution and intercrystalline mixtures of hydroxyapatite and octacalcium phosphate. This work investigates which of the models mentioned suits better in a range of samples. Hydroxyapatites obtained by precipitation, by hydrolysis of dicalcium phosphate and calcined samples with Ca/P ratio between 1.50 and 1.77 and specific surface area between 7 and 108 m2/g have been analysed. OCP and surface adsorption models suit better for great SSA particles and low Ca/P ratio while for smaller SSA particles the lattice substitution model is more accurate. SSA also plays the main role when the capacity to absorb substances is studied though their chemistry can not be explained solely in terms of surface reactivity.