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3.
J Mater Sci Mater Med ; 31(11): 100, 2020 Oct 31.
Article in English | MEDLINE | ID: mdl-33130982

ABSTRACT

The use of 3D scaffolds based on mesoporous bioactive glasses (MBG) enhanced with therapeutic ions, biomolecules and cells is emerging as a strategy to improve bone healing. In this paper, the osteogenic capability of ZnO-enriched MBG scaffolds loaded or not with osteostatin (OST) and human mesenchymal stem cells (MSC) was evaluated after implantation in New Zealand rabbits. Cylindrical meso-macroporous scaffolds with composition (mol %) 82.2SiO2-10.3CaO-3.3P2O5-4.2ZnO (4ZN) were obtained by rapid prototyping and then, coated with gelatin for easy handling and potentiating the release of inorganic ions and OST. Bone defects (7.5 mm diameter, 12 mm depth) were drilled in the distal femoral epiphysis and filled with 4ZN, 4ZN + MSC, 4ZN + OST or 4ZN + MSC + OST materials to evaluate and compare their osteogenic features. Rabbits were sacrificed at 3 months extracting the distal third of bone specimens for necropsy, histological, and microtomography (µCT) evaluations. Systems investigated exhibited bone regeneration capability. Thus, trabecular bone volume density (BV/TV) values obtained from µCT showed that the good bone healing capability of 4ZN was significantly improved by the scaffolds coated with OST and MSC. Our findings in vivo suggest the interest of these MBG complete systems to improve bone repair in the clinical practice.


Subject(s)
Fractures, Bone/therapy , Glass/chemistry , Mesenchymal Stem Cells/cytology , Parathyroid Hormone-Related Protein/chemistry , Peptide Fragments/chemistry , Tissue Scaffolds/chemistry , Zinc Oxide/chemistry , Animals , Biocompatible Materials , Bone Regeneration , Female , Ions , Materials Testing , Osteogenesis , Porosity , Rabbits , X-Ray Microtomography , Zinc/chemistry
6.
Acta Biomater ; 114: 395-406, 2020 09 15.
Article in English | MEDLINE | ID: mdl-32717329

ABSTRACT

Bone regeneration is a clinical challenge which requires multiple approaches. Sometimes, it also includes the development of osteogenic and antibacterial biomaterials to treat the emergence of possible infection processes arising from surgery. This study evaluates the antibacterial properties of gelatin-coated meso-macroporous scaffolds based on the bioactive glass 80%SiO2-15%CaO-5%P2O5 (mol-%) before (BL-GE) and after being doped with 4% of ZnO (4ZN-GE) and loaded with both saturated and the minimal inhibitory concentrations of one of the antibiotics: levofloxacin (LEVO), vancomycin (VANCO), rifampicin (RIFAM) or gentamicin (GENTA). After physical-chemical characterization of materials, release studies of inorganic ions and antibiotics from the scaffolds were carried out. Moreover, molecular modelling allowed determining the electrostatic potential density maps and the hydrogen bonds of antibiotics and the glass matrix. Antibacterial in vitro studies (in planktonic, inhibition halos and biofilm destruction) with S. aureus and E. coli as bacteria models showed a synergistic effect of zinc ions and antibiotics. The effect was especially noticeable in planktonic cultures of S. aureus with 4ZN-GE scaffolds loaded with VANCO, LEVO or RIFAM and in E. coli cultures with LEVO or GENTA. Moreover, S. aureus biofilms were completely destroyed by 4ZN-GE scaffolds loaded with VANCO, LEVO or RIFAM and the E. coli biofilm total destruction was accomplished with 4ZN-GE scaffolds loaded with GENTA or LEVO. This approach could be an important step in the fight against microbial resistance and provide needed options for bone infection treatment. STATEMENT OF SIGNIFICANCE: Antibacterial capabilities of scaffolds based on mesoporous bioactive glasses before and after adding a 4% ZnO and loading with saturated and minimal inhibitory concentrations of levofloxacin, vancomycin, gentamicin or rifampicin were evaluated. Staphylococcus aureus and Escherichia coli were the infection model strains for the performed assays of inhibition zone, planktonic growth and biofilm. Good inhibition results and a synergistic effect of zinc ions released from scaffolds and antibiotics were observed. Thus, the amount of antibiotic required to inhibit the bacterial planktonic growth was substantially reduced with the ZnO inclusion in the scaffold. This study shows that the ZnO-MBG osteogenic scaffolds are multifunctional tools in bone tissue engineering because they are able to fight bacterial infections with lower antibiotic dosage.


Subject(s)
Anti-Bacterial Agents , Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Escherichia coli , Glass , Silicon Dioxide , Tissue Scaffolds , Zinc
7.
Opt Express ; 27(8): A257-A268, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-31052880

ABSTRACT

Heliostat alignment evaluation is among the main issues in solar tower concentration plant operation and maintenance. This paper describes a novel method used to evaluate heliostat misalignment and its experimental verification. This method provides a different way of visualizing beam centroid pointing errors by generating the complete deviation curve for each axis. This, for example, would be useful for verifying a heliostat's correct alignment by using a measurement performed out of the receiver target, using these traces to calculate its reflection's expected location, given a known misalignment. This measurement could be performed during operation simply by including a reflective element in the heliostat and two detector arrays on the tower's surface. This model has been tested for various types of misalignments of a heliostat at different hours, dates, and heliostat locations. The simulation results have been validated by using an experimental setup at a scale of 1:100.

8.
Acta Biomater ; 89: 359-371, 2019 04 15.
Article in English | MEDLINE | ID: mdl-30890462

ABSTRACT

There is an urgent need of biosynthetic bone grafts with enhanced osteogenic capacity. In this study, we describe the design of hierarchical meso-macroporous 3D-scaffolds based on mesoporous bioactive glasses (MBGs), enriched with the peptide osteostatin and Zn2+ ions, and their osteogenic effect on human mesenchymal stem cells (hMSCs) as a preclinical strategy in bone regeneration. The MBG compositions investigated were 80%SiO2-15%CaO-5%P2O5 (in mol-%) Blank (BL), and two analogous glasses containing 4% ZnO (4ZN) and 5% ZnO (5ZN). By using additive fabrication techniques, scaffolds exhibiting hierarchical porosity: mesopores (around 4 nm), macropores (1-600 µm) and big channels (∼1000 µm), were prepared. These MBG scaffolds with or without osteostatin were evaluated in hMCSs cultures. Zinc promoted hMSCs colonization (both the surface and inside) of MBG scaffolds. Moreover, Zn2+ ions and osteostatin together, but not independently, in the scaffolds were found to induce the osteoblast differentiation genes runt related transcription factor-2 (RUNX2) and alkaline phosphatase (ALP) in hMSCs after 7 d of culture in the absence of an osteogenic differentiation-promoting medium. These results add credence to the combined use of zinc and osteostatin as an effective strategy for bone regeneration applications. STATEMENT OF SIGNIFICANCE: Mesoporous bioactive glasses (MBGs) are bioceramics whose unique properties make them excellent materials for bone tissue engineering. Physico-chemical characterization of MBGs as scaffolds made by rapid prototyping, doped with zinc (potential osteogenic, angiogenic and bactericidal ion) and loaded with osteostatin (osteogenic peptide) are described. These Zn-MBGs scaffolds showed 3D hierarchical meso-macroporous structure that enables to host and release osteostatin. When decorated with human mesenchymal stem cells (hMSCs), MBGs scaffoldsenriched with both zinc and osteostatin exhibited a synergistic effect to enhance hMSCs growth, and also hMSCs osteogenic differentiationwithout addition of other osteoblastic differentiation factors to the culture medium. This novel strategy has a great potential for use in bone tissue engineering.


Subject(s)
Cell Differentiation , Glass/chemistry , Mesenchymal Stem Cells/metabolism , Osteoblasts/metabolism , Osteocalcin/pharmacology , Tissue Scaffolds/chemistry , Zinc/chemistry , Cations, Divalent/chemistry , Humans , Mesenchymal Stem Cells/cytology , Osteoblasts/cytology , Porosity
9.
Article in English | MEDLINE | ID: mdl-27106813

ABSTRACT

We test the capabilities of in situ Raman spectroscopy for non-destructive analysis of degradation processes in invaluable masterpieces, as well as for the characterization of minerals and prehistoric rock-art in caves. To this end, we have studied the mechanism of decay suffered by the 15th-century limestone sculptures that decorate the retro-choir of Burgos Cathedral (N Spain). In situ Raman probe detected hydrated sulfate and nitrate minerals on the sculptures, which are responsible for the decay of the original limestone. In addition, in situ Raman analyses were performed on unique speleothems in El Soplao Cave (Cantabria, N Spain) and in the Gruta de las Maravillas (Aracena, SW Spain). Unusual cave minerals were detected in El Soplao Cave, such as hydromagnesite (Mg5(CO3)4(OH)2·4H2O), as well as ferromanganese oxides in the black biogenic speleothems recently discovered in this cavern. In the Gruta de las Maravillas, gypsum (CaSO4·2H2O) was identified for the first time, as part of the oldest cave materials, so providing additional evidence of hypogenic mechanisms that occurred in this cave during earlier stages of its formation. Finally, we present preliminary analyses of several cave paintings in the renowned "Polychrome Hall" of Altamira Cave (Cantabria, N. Spain). Hematite (Fe2O3) is the most abundant mineral phase, which provides the characteristic ochre-reddish color to the Altamira bison and deer paintings. Thus, portable Raman spectroscopy is demonstrated to be an analytical technique compatible with preserving our cultural and natural heritage, since the analysis does not require physical contact between the Raman head and the analyzed items.

10.
Radiología (Madr., Ed. impr.) ; 58(1): 7-15, ene.-feb. 2016. ilus, graf
Article in Spanish | IBECS | ID: ibc-149240

ABSTRACT

La insuficiencia venosa crónica (IVC) de las extremidades inferiores es una enfermedad muy prevalente. La ecografía Doppler se ha establecido en las últimas décadas como el método de elección en el estudio de esta patología, por lo que resulta imprescindible ante una eventual indicación quirúrgica. El objetivo de este trabajo es establecer una metodología en la exploración, incluyendo la realización de cartografía y el marcaje prequirúrgico. Para ello revisaremos la anatomía venosa de los miembros inferiores y la fisiopatología de la IVC explicando los conceptos hemodinámicos básicos y la terminología necesarios para la realización de un informe radiológico que permita una adecuada planificación terapéutica y comunicación con otros especialistas. Explicaremos brevemente la estrategia CHIVA (cura hemodinámica de la insuficiencia venosa ambulatoria), método quirúrgico mínimamente invasivo que tiene como objetivo restaurar la hemodinámica venosa sin extirpar la vena safena (AU)


Chronic venous insufficiency of the lower limbs is very prevalent. In recent decades, Doppler ultrasound has become the method of choice to study this condition, and it is considered essential when surgery is indicated. This article aims to establish a method for the examination, including venous mapping and preoperative marking. To this end, we review the venous anatomy of the lower limbs and the pathophysiology of chronic venous insufficiency and explain the basic hemodynamic concepts and the terminology required to elaborate a radiological report that will enable appropriate treatment planning and communication with other specialists. We briefly explain the CHIVA (the acronym for the French term "cure conservatrice et hémodynamique de l'insuffisance veineuse en ambulatoire" = conservative hemodynamic treatment for chronic venous insufficiency) strategy, a minimally invasive surgical strategy that aims to restore correct venous hemodynamics without resecting the saphenous vein (AU)


Subject(s)
Humans , Male , Female , Venous Insufficiency/blood , Ultrasonography, Doppler, Duplex/nursing , Saphenous Vein/pathology , Venous Pressure/genetics , Ulcer/diagnosis , Atrophy/metabolism , Atrophy/pathology , Venous Insufficiency/therapy , Ultrasonography, Doppler, Duplex/instrumentation , Saphenous Vein/abnormalities , Venous Pressure/physiology , Ulcer/complications , Atrophy/complications , Atrophy/diagnosis
11.
Radiologia ; 58(1): 7-15, 2016.
Article in English, Spanish | MEDLINE | ID: mdl-26655801

ABSTRACT

Chronic venous insufficiency of the lower limbs is very prevalent. In recent decades, Doppler ultrasound has become the method of choice to study this condition, and it is considered essential when surgery is indicated. This article aims to establish a method for the examination, including venous mapping and preoperative marking. To this end, we review the venous anatomy of the lower limbs and the pathophysiology of chronic venous insufficiency and explain the basic hemodynamic concepts and the terminology required to elaborate a radiological report that will enable appropriate treatment planning and communication with other specialists. We briefly explain the CHIVA (the acronym for the French term "cure conservatrice et hémodynamique de l'insuffisance veineuse en ambulatoire"=conservative hemodynamic treatment for chronic venous insufficiency) strategy, a minimally invasive surgical strategy that aims to restore correct venous hemodynamics without resecting the saphenous vein.


Subject(s)
Ultrasonography, Doppler , Venous Insufficiency/diagnostic imaging , Humans , Veins/diagnostic imaging
15.
Biomed Res Int ; 2014: 257517, 2014.
Article in English | MEDLINE | ID: mdl-24790994

ABSTRACT

The aim of this study was to investigate the frequency and mutation status of the immunoglobulin heavy variable chain (IGHV) in a cohort of 224 patients from northwest and central region of Spain diagnosed with chronic lymphocytic leukemia (CLL), and to correlate it with cytogenetic abnormalities, overall survival (OS) and time to first treatment (TTFT). 125 patients had mutated IGHV, while 99 had unmutated IGHV. The most frequently used IGHV family was IGHV3, followed by IGHV1 and IGHV4. The regions IGHV3-30, IGHV1-69, IGHV3-23, and IGHV4-34 were the most commonly used. Only 3.1% of the patients belonged to the subfamily IGHV3-21 and we failed to demonstrate a worse clinical outcome in this subgroup. The IGHV4 family appeared more frequently with mutated pattern, similar to IGHV3-23 and IGHV3-74. By contrast, IGHV1-69 was expressed at a higher frequency in unmutated CLL patients. All the cases from IGHV3-11 and almost all from IGHV5-51 subfamily belonged to the group of unmutated CLL.


Subject(s)
Gene Rearrangement/genetics , Genes, Immunoglobulin Heavy Chain/genetics , Genetic Predisposition to Disease/epidemiology , Genetic Predisposition to Disease/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/epidemiology , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Adult , Aged , Aged, 80 and over , Base Sequence , Female , Genetic Markers/genetics , Humans , Incidence , Male , Middle Aged , Molecular Sequence Data , Mutation/genetics , Prevalence , Risk Factors , Spain/epidemiology , Spatio-Temporal Analysis
16.
Ann Fr Anesth Reanim ; 33(3): 163-6, 2014 Mar.
Article in French | MEDLINE | ID: mdl-24582109

ABSTRACT

OBJECTIVES: Emergency cricothyroidotomy is recommended as life-saving maneuver when mask ventilation and tracheal intubation are impossible. It requires the puncture of the cricothyroid membrane (CTM) whose clinical identification is difficult. The objective of this study is to evaluate if ultrasound can help locating the CTM by comparing palpation and ultrasonographic evaluation. PATIENTS AND METHODS: After ultrasound localization of CTM by a referent physician in two overweight volunteers, twelve residents without prior anatomy recall, defined by palpation an entry point for CTM. After a rapid training in CTM ultrasound localization, residents identified an ultrasound-guided puncture point. For each puncture site were registered: relevance, time and ease to localization. Six months later, residents renewed clinical and ultrasound identification of CTM on the same subjects. RESULTS: The CTM was accurately identified by palpation and ultrasound by 46% and 100% of residents respectively (P<0.05). Six months later, residents remained more effective identifying CTM with ultrasound than with palpation (78% vs. 33%) (P<0.05). Time to localization of CTM by palpation in the 2 volunteers was 15 s [11-18] and 24 s [9-39] (average [CI 95%]) whereas it was 21 s [16-25 s] and 28 s [19-36] by ultrasound respectively (ns). The ultrasound identification of CTM was also considered easier than clinical identification. CONCLUSION: Following a limited training phase, ultrasound allowed a more effective localization of CTM by residents when compared to clinical palpation in overweight patients. This benefit remained significant when assessment was repeated 6 months later.


Subject(s)
Airway Management/methods , Anesthesiology/education , Cricoid Cartilage/diagnostic imaging , Cricoid Cartilage/surgery , Thyroid Cartilage/diagnostic imaging , Thyroid Cartilage/surgery , Emergency Medical Services , Female , Humans , Internship and Residency , Intubation, Intratracheal , Male , Middle Aged , Palpation , Thyroidectomy/methods , Ultrasonography, Interventional/methods
18.
Dermatol Online J ; 18(8): 12, 2012 Aug 15.
Article in English | MEDLINE | ID: mdl-22948062

ABSTRACT

A 48-year-old woman developed drug-induced subacute lupus erythematosus while taking lamotrigine. The eruption resolved after discontinuance of lamotrigine, suggesting this drug as the cause.


Subject(s)
Anticonvulsants/adverse effects , Lupus Erythematosus, Cutaneous/chemically induced , Triazines/adverse effects , Drug Eruptions/immunology , Female , Humans , Lamotrigine , Lupus Erythematosus, Cutaneous/immunology , Middle Aged
19.
Science ; 336(6087): 1409-13, 2012 Jun 15.
Article in English | MEDLINE | ID: mdl-22700921

ABSTRACT

Paleolithic cave art is an exceptional archive of early human symbolic behavior, but because obtaining reliable dates has been difficult, its chronology is still poorly understood after more than a century of study. We present uranium-series disequilibrium dates of calcite deposits overlying or underlying art found in 11 caves, including the United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage sites of Altamira, El Castillo, and Tito Bustillo, Spain. The results demonstrate that the tradition of decorating caves extends back at least to the Early Aurignacian period, with minimum ages of 40.8 thousand years for a red disk, 37.3 thousand years for a hand stencil, and 35.6 thousand years for a claviform-like symbol. These minimum ages reveal either that cave art was a part of the cultural repertoire of the first anatomically modern humans in Europe or that perhaps Neandertals also engaged in painting caves.


Subject(s)
Caves , Engraving and Engravings/history , Paintings/history , Radiometric Dating , Animals , Calcium Carbonate , Culture , History, Ancient , Humans , Neanderthals , Spain , Uranium
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