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1.
Clin Oral Investig ; 28(8): 421, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976067

RESUMEN

AIM: To investigate the outcome of elective full pulpotomy, using calcium silicate-based cements (CSBC), after 2 years, in symptomatic mature permanent teeth with carious lesions, diagnosed as irreversible pulpitis, and analyse the capacity of Wolters et al. (2017) classification to predict the likelihood of treatment failure. METHODS: The treatment records of 56 patients with symptomatic mature teeth with carious lesions, diagnosed as irreversible pulpitis and treated by elective full pulpotomy, using CSBCs as pulp capping materials, were reviewed. Thirteen teeth were excluded. The remaining 43 teeth were evaluated retrospectively at 24 months. Fisher`s exact test with the Lancaster's mid-P adjustment was used to assess different outcomes amongst the diagnostic categories. RESULTS: Four of the cases failed before 24 months and required root canal treatment (RCT). Overall success rate at 2 years was 90.7% (39 of 43). An inverse, but non-significant, correlation was observed between the severity of pulpitis according to the Wolters classification and the treatment success rate (p > 0.05). The type of CSBC used was associated to the success rate (OR = 10.5; 95% C.I. = 0.5 - 207.4; p = 0.027), being 82% with Endosequence and 100% with Biodentine. Postoperative pain associated significantly to lower success rate (66.7%) (Odds ratio = 8.0; 95% C.I. = 0.7 - 95.9; p = 0.047). CONCLUSIONS: Elective full pulpotomy using a CSBC was a successful choice for the treatment of mature permanent teeth with symptoms indicative of irreversible pulpitis. There were no significant differences between the success rate of mild, moderate and severe pulpitis. Postoperative pain could be considered a risk marker for failure of full pulpotomy. The term "irreversible pulpitis" should be re-signified to indicate the need for access to the pulp chamber, rather than an indication for extraction or RCT.


Asunto(s)
Compuestos de Calcio , Pulpitis , Pulpotomía , Silicatos , Humanos , Pulpotomía/métodos , Pulpitis/cirugía , Estudios Retrospectivos , Femenino , Masculino , Silicatos/uso terapéutico , Compuestos de Calcio/uso terapéutico , Adulto , Caries Dental/terapia , Caries Dental/cirugía , Resultado del Tratamiento , Persona de Mediana Edad , Cementos Dentales , Materiales de Recubrimiento Pulpar y Pulpectomía/uso terapéutico , Dentición Permanente , Adolescente
2.
Int J Mol Sci ; 25(1)2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38203286

RESUMEN

Black phosphorus (BP) is one of the most promising nanomaterials for cancer therapy. This 2D material is biocompatible and has strong photocatalytic activity, making it a powerful photosensitiser for combined NIR photothermal and photodynamic therapies. However, the fast degradation of BP in oxic conditions (including biological environments) still limits its use in cancer therapy. This work proposes a facile strategy to produce stable and highly concentrated BP suspensions using lysolipid temperature-sensitive liposomes (LTSLs). This approach also allows for co-encapsulating BP nanoflakes and doxorubicin, a potent chemotherapeutic drug. Finally, we demonstrate that our BP/doxorubicin formulation shows per se high antiproliferative action against an in vitro prostate cancer model and that the anticancer activity can be enhanced through NIR irradiance.


Asunto(s)
Liposomas , Neoplasias de la Próstata , Masculino , Humanos , Temperatura , Neoplasias de la Próstata/tratamiento farmacológico , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Fósforo
3.
Chem Soc Rev ; 49(17): 6224-6247, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-32724940

RESUMEN

A large number of graphene and other 2D materials are currently used for the development of new technologies, increasingly entering different industrial sectors. Interrogating the impact of such 2D materials on health and environment is crucial for both modulating their potential toxicity in living organisms and eliminating them from the environment. In this context, understanding if 2D materials are bio-persistent is mandatory. In this review we describe the importance of biodegradability and decomposition of 2D materials. We initially cover the biodegradation of graphene family materials, followed by other emerging classes of 2D materials including transition metal dichalcogenides and oxides, Xenes, Mxenes and other non-metallic 2D materials. We explain the role of defects and functional groups, introduced onto the surface of the materials during their preparation, and the consequences of chemical functionalization on biodegradability. In strong relation to the chemistry on 2D materials, we describe the concept of "degradation-by-design" that we contributed to develop, and which concerns the covalent modification with appropriate molecules to enhance the biodegradability of 2D materials. Finally, we cover the importance of designing new biodegradable 2D conjugates and devices for biomedical applications as drug delivery carriers, in bioelectronics, and tissue engineering. We would like to highlight that the biodegradation of 2D materials mainly depends on the type of material, the chemical functionalization, the aqueous dispersibility and the redox potentials of the different oxidative environments. Biodegradation is one of the necessary conditions for the safe application of 2D materials. Therefore, we hope that this review will help to better understand their biodegradation processes, and will stimulate the chemists to explore new chemical strategies to design safer products, composites and devices containing 2D materials.


Asunto(s)
Materiales Biocompatibles , Biodegradación Ambiental , Sistemas de Liberación de Medicamentos , Grafito
4.
J Oral Maxillofac Surg ; 74(7): 1344-53, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27070843

RESUMEN

PURPOSE: Implant stability is a clinically valuable measurement of the strength of implant anchorage in the bone during placement and in the post-osseointegration period. This study aimed to determine 1) the effect of implant diameter and length and bone quality on measurements of primary and secondary stability (insertion torque [IT] and implant stability quotient [ISQ]), 2) the correlation between IT and primary and secondary ISQ, and 3) differences in ISQ in the post-osseointegration period (secondary stability) compared with immediate post-placement (primary) stability. PATIENTS AND METHODS: In this longitudinal clinical study, titanium self-tapping implants were inserted in edentulous patients. The implants were grouped according to 3 independent variables: length (10 and 11.5 mm), diameter (3.75 and 4.25 mm), and bone quality (Lekholm and Zarb classification) to analyze primary and secondary implant stability (outcome variables). Statistical analyses were performed using the Student t test for paired data, 1-way analysis of variance, and the Tukey procedure for multiple pairwise comparisons. RESULTS: Data were collected on 88 self-tapping implants inserted in 63 partially edentulous patients. IT and implant stability were affected by diameter (3.75-mm implants, 26.5-N/cm IT and 74.0 ISQ; 4.25-mm implants, 33.8-N/cm IT and 77.0 ISQ) and bone type (type 1 + 2, 34.86-N/cm IT and 77.4 ISQ; type 3, 27.09-N/cm IT and 75.6 ISQ; type 4, 20.63-N/cm IT and 70.5 ISQ; P < .01 for all comparisons). Secondary ISQ was affected by diameter only (77.41 for 3.75- vs 75.51 for 4.25-mm implants). IT correlated with primary ISQ (R = 0.56; P < .01), although no clear correlation with secondary stability was found. CONCLUSIONS: IT and primary ISQ in self-tapping implants differed in patients with different bone quality and implant diameter but did not differ between the 2 implant lengths compared in this study. Secondary stability was not substantially affected by any of these factors. Although IT was closely related to primary ISQ, it was unrelated to secondary ISQ. Very high primary ISQ values tended to decrease, whereas intermediate and low values tended to increase, in the transition to secondary stability.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Diseño de Prótesis Dental , Retención de Prótesis Dentales , Pérdida de Hueso Alveolar/clasificación , Femenino , Humanos , Arcada Parcialmente Edéntula/rehabilitación , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Oseointegración , Titanio , Torque , Resultado del Tratamiento
5.
Dent Update ; 43(10): 964-6, 968-70, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29155538

RESUMEN

Root resorption is the loss of hard dental tissue as a result of odontoclastic action involving vital and pulpless teeth. Cervical root resorption (CRR) is a type of external resorption which usually occurs immediately below the epithelial attachment of the tooth in the cervical region. The idiopathic cervical resorption (ICR) refers to a clinical situation in which all other causes, whether local or systemic, have been ruled out as the origin of the disease. The early stage is asymptomatic and might be diagnosed by a routine radiograph or a clinical examination. In this study, the aetiological, histological, clinical and radiological analysis is undertaken; a review is made concerning the pathologies to which the differential diagnosis should be applied; and the different therapeutical options are discussed. This lesion sometimes demands the management of a broad field of multidisciplinary techniques such as restorative dentistry, endodontics, surgery, implants and prosthesis. Clinical relevance: Cone-beam computed tomography (CBCT) may be a useful tool to determine the true extent of external cervical resorption lesions.


Asunto(s)
Resorción Radicular , Cuello del Diente , Humanos , Resorción Radicular/diagnóstico , Resorción Radicular/etiología , Resorción Radicular/terapia
7.
Photochem Photobiol Sci ; 13(9): 1241-52, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24969364

RESUMEN

Herein, we demonstrate the design of multiple fluorophores Coumarin 153 (C153) and Nile Red (NR) encapsulated in semiconducting poly[N-vinylcarbazole] (PVK) polymer nanoparticles (50-70 nm in diameter) by a simple re-precipitation technique, and elucidate their photophysical properties by steady-state and picosecond (ps) time resolved emission spectroscopy. It is interesting to note that multistep cascaded energy transfer occurs from the excited host PVK molecules to NR dye molecules through C153. The energy transfer time constants are found to be 180 ps for PVK→C153, 360 ps for PVK→NR, and 140 ps for the overall energy transfer process from PVK to NR through C153 dye molecules. The multistep energy transfer allows tuning of the wide range emission from 350 nm to 700 nm by changing the relative concentrations of the encapsulated dye molecules. Bright, stable, and white light emission of the dye doped polymer nanoparticles with a quantum yield of 14% is achieved at a particular concentration ratio of the C153 : NR dye. The generation of "cool" white emission in suspension and in the solid state film opens up new possibilities to obtain white light OLEDs based on single nanoparticles.


Asunto(s)
Nanopartículas/química , Polímeros/química , Cumarinas/química , Transferencia Resonante de Energía de Fluorescencia , Colorantes Fluorescentes/química , Tamaño de la Partícula , Polímeros/síntesis química , Espectrofotometría Ultravioleta , Rayos Ultravioleta
8.
Int J Biol Macromol ; 268(Pt 2): 131647, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38653432

RESUMEN

Herein, we describe a detailed protocol to extract the mucilage from different species of the genus Opuntia spp. (i.e., Opuntia Ficus (OFi), Opuntia Dillenii (ODi) and Opuntia Robusta (ORo)). The extracted mucilage was characterized by NMR, FTIR-ATR, HPLC, and TGA. OFi was found to have the highest phenolic content, 7.84 ± 1.93 mg catechol/g mucilage. The mucilage from the three species were characterized by having a high content of monosaccharides, being mannose and glucose the most abundant components (ca. 48-73 % and 23-35 %, respectively). In the context of biomass revalorization, the mucilage was proven to serve as a reducing and stabilizing agent in the synthesis of gold nanoparticles (AuNP/mucilage). The synthesis was optimized with a mucilage concentration of 2 mg/mL using 12.5 µL of KAuCl4 and was carried out at 80 °C for 90 min. This protocol afforded spherical nanoparticles with an average size of 9.7 ± 4.0 nm that were stable for at least 14 days, as demonstrated by TEM. Synthesized AuNP/mucilage was evaluated as a plasmonic catalyst for the reduction of 4-nitrophenol as model reaction, showing a considerable enhancement in its kapp of 97 % under white light and a decrease of 24.8 % in its activation energy.


Asunto(s)
Oro , Opuntia , Mucílago de Planta , Opuntia/química , Mucílago de Planta/química , Oro/química , Nanopartículas del Metal/química , Fenoles/química , Extractos Vegetales/química , Monosacáridos/química , Monosacáridos/análisis
9.
Biomed Pharmacother ; 174: 116492, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38537579

RESUMEN

Targeting epigenetic mechanisms has emerged as a potential therapeutic approach for the treatment of kidney diseases. Specifically, inhibiting the bromodomain and extra-terminal (BET) domain proteins using the small molecule inhibitor JQ1 has shown promise in preclinical models of acute kidney injury (AKI) and chronic kidney disease (CKD). However, its clinical translation faces challenges due to issues with poor pharmacokinetics and side effects. Here, we developed engineered liposomes loaded with JQ1 with the aim of enhancing kidney drug delivery and reducing the required minimum effective dose by leveraging cargo protection. These liposomes efficiently encapsulated JQ1 in both the membrane and core, demonstrating superior therapeutic efficacy compared to freely delivered JQ1 in a mouse model of kidney ischemia-reperfusion injury. JQ1-loaded liposomes (JQ1-NPs) effectively targeted the kidneys and only one administration, one-hour after injury, was enough to decrease the immune cell (neutrophils and monocytes) infiltration to the kidney-an early and pivotal step to prevent damage progression. By inhibiting BRD4, JQ1-NPs suppress the transcription of pro-inflammatory genes, such as cytokines (il-6) and chemokines (ccl2, ccl5). This success not only improved early the kidney function, as evidenced by decreased serum levels of BUN and creatinine in JQ1-NPs-treated mice, along with reduced tissue expression of the damage marker, NGAL, but also halted the production of extracellular matrix proteins (Fsp-1, Fn-1, α-SMA and Col1a1) and the fibrosis development. In summary, this work presents a promising nanotherapeutic strategy for AKI treatment and its progression and provides new insights into renal drug delivery.


Asunto(s)
Azepinas , Proteínas que Contienen Bromodominio , Progresión de la Enfermedad , Riñón , Liposomas , Ratones Endogámicos C57BL , Proteínas Nucleares , Insuficiencia Renal Crónica , Daño por Reperfusión , Triazoles , Animales , Azepinas/farmacología , Azepinas/administración & dosificación , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/patología , Triazoles/farmacología , Triazoles/administración & dosificación , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/patología , Ratones , Riñón/efectos de los fármacos , Riñón/patología , Riñón/metabolismo , Masculino , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Lesión Renal Aguda/tratamiento farmacológico , Lesión Renal Aguda/prevención & control , Modelos Animales de Enfermedad , Nanopartículas , Proteínas de Ciclo Celular/antagonistas & inhibidores
10.
J Mater Chem B ; 11(2): 316-324, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36353924

RESUMEN

Population growth, depletion of world resources and persistent toxic chemical production underline the need to seek new smart materials from inexpensive, biodegradable, and renewable feedstocks. Hence, "metal-free" ring-opening copolymerization to convert biomass carvone-based monomers into non-conventional luminescent biopolymers is considered a sustainable approach to achieve these goals. The non-conventional emission was studied in terms of steady-state and time-resolved spectroscopy in order to unravel the structure-properties for different carvone-based copolymers. The results highlighted the importance of the final copolymer folding structure as well as its environment in luminescent behavior (cluster-triggered emission). In all cases, their luminescent behavior is sensitive to small temperature fluctuations (where the minimum detected temperature is Tm ∼ 2 °C and relative sensitivity is Sr ∼ 6% °C) even at the microscopic scale, which endows these materials a great potential as thermosensitive smart polymers for photothermal imaging.


Asunto(s)
Luminiscencia , Polímeros , Polímeros/química , Biomasa , Monoterpenos Ciclohexánicos
11.
Chem Commun (Camb) ; 55(39): 5540-5546, 2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-31033990

RESUMEN

The potential risks associated with two-dimensional (2D) nanomaterials may cause serious concerns about their real applications and impact in biological systems. In addition, the demonstration of biodegradability of these flat nanomaterials is essential in living organisms. Here, we summarise the state-of-the-art in the field of biocompatibility and biodegradability of graphene-related materials (such as 2D materials like MoS2, BN or WS2). The impact of chemical functionalisation on the potential control of the biodegradability profile of these structures is also discussed.


Asunto(s)
Materiales Biocompatibles/química , Grafito/química , Animales , Materiales Biocompatibles/metabolismo , Compuestos de Boro/química , Bovinos , Disulfuros/química , Molibdeno/química , Nanoestructuras/química , Polietilenglicoles/química , Polietilenglicoles/metabolismo , Albúmina Sérica Bovina/metabolismo , Tungsteno/química
12.
Dent Mater J ; 27(2): 284-91, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18540405

RESUMEN

The present study, divided into two parts, analyses the stability and reproducibility of the spectral and energy emission of the present light-curing units (LCUs), quartz tungsten halogen (QTH) and light-emitting diodes (LEDs). In part I, QTH LCUs were studied. The results showed that the QTH LCUs studied presented high stability and reproducibility in terms of their spectral emission with VAF (variance accounting for) values from the Cauchy-Schwarz inequality, all close to 100%. With respect to the energy stability, the QTH LCUs studied can be considered stable under practical clinical conditions, although for some devices the initial irradiance value is critical. This result should be taken into account in those works which is researched in polymerization kinetics of dental materials as well as in clinical practice.


Asunto(s)
Equipo Dental , Luz , Halógenos , Transición de Fase , Fotometría
13.
Dent Mater J ; 27(2): 292-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18540406

RESUMEN

The present work is the second part of a study on the stability and reproducibility of the energy and spectral emission of some light curing units (LCUs). In this part, Part II, LED LCUs were investigated. Results revealed that these devices presented high stability and reproducibility in terms of their spectral emission, with values of VAF (variance accounting for) coefficient calculated from the Cauchy-Schwarz inequality all close to 100%. With respect to energy stability, the LED LCUs presented energy stability except for the third-generation LED LCUs which have several LEDs. For these devices, the law of reciprocity was not fulfilled as irradiance was not constant over exposure time. This result should be taken into account both in works examining the polymerization kinetics of dental materials as well as when these LED LCUs are used in clinical practice.


Asunto(s)
Equipo Dental , Luz , Semiconductores , Transición de Fase , Fotometría
14.
Sci Rep ; 7(1): 10942, 2017 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-28887551

RESUMEN

In tissue engineering strategies, the design of scaffolds based on nanostructures is a subject undergoing intense research: nanomaterials may affect the scaffolds properties, including their ability to interact with cells favouring cell growth and improving tissue performance. Hydrogels are synthetic materials widely used to obtain realistic tissue constructs, as they resemble living tissues. Here, different hydrogels with varying content of graphene, are synthesised by in situ radical polymerization of acrylamide in aqueous graphene dispersions. Hydrogels are characterised focusing on the contribution of the nanomaterial to the polymer network. Our results suggest that graphene is not a mere embedded nanomaterial within the hydrogels, rather it represents an intrinsic component of these networks, with a specific role in the emergence of these structures. Moreover, a hybrid hydrogel with a graphene concentration of only 0.2 mg mL-1 is used to support the growth of cultured brain cells and the development of synaptic activity, in view of exploiting these novel materials to engineer the neural interface of brain devices of the future. The main conclusion of this work is that graphene plays an important role in improving the biocompatibility of polyacrylamide hydrogels, allowing neuronal adhesion.


Asunto(s)
Grafito/química , Hidrogeles/química , Neuronas/citología , Andamios del Tejido/química , Resinas Acrílicas/química , Animales , Células Cultivadas , Hidrogeles/efectos adversos , Neuronas/efectos de los fármacos , Neuronas/fisiología , Ratas , Transmisión Sináptica/efectos de los fármacos , Andamios del Tejido/efectos adversos
15.
Eur J Pharm Sci ; 106: 159-165, 2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28577996

RESUMEN

Itraconazole-loaded micro/nanoparticles containing albumin and liposomes were prepared by a technological process that avoids the use of organic solvents and crosslinker agents. The particles were characterized, lyophilized and formulated as tablets. Dynamic light scattering was used to determine the hydrodynamic diameter and zeta potential of the particles; optical and scanning-electron microscopy was used to evaluate their morphology. Spherical shaped particles of different sizes and zeta potential were obtained. An exponential relationship between the zeta potential and the albumin/cationic lipid molar ratio was established. Drug entrapment efficiency values were in the range of 51-68%, with no statistical differences among albumin feeding concentrations. Mannitol was used as lyophilization additive and the freeze-dried cake was directly compressed into tablets, suitable for vaginal administration. The results from the in vitro drug delivery assay show the influence of albumin on the itraconazole delivery profile; a rapid release was observed for particles with higher albumin amount compared to those with lower protein content. According to the results of this study, albumin particles entrapping liposomes prove to be a green pharmaceutical vehicle with a high potential for delivery of hydrophobic and highly albumin-bound drugs.


Asunto(s)
Albúminas/química , Itraconazol/química , Liposomas/síntesis química , Nanopartículas/química , Calibración , Química Farmacéutica/métodos , Cromatografía Líquida de Alta Presión/métodos , Portadores de Fármacos/química , Liberación de Fármacos , Liofilización/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Propiedades de Superficie
16.
J Clin Exp Dent ; 9(8): e1044-e1050, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28936297

RESUMEN

INTRODUCTION: Cardiovascular diseases are the most frequent cause of death in the Western world. Its treatment frequently needs therapy with antiplatelet agents, which increases the haemorrhage risk after oral surgical procedures. The aim of this study is to present a review on the dental management of the patients under antiplatelet treatment. MATERIAL AND METHODS: A systematic review was carried out following PRISMA recommendations including studies searched in Pubmed-Medline, Embase and Cochrane databases. RESULTS: The current trend is to maintain the treatment during the surgical procedure, assuring a good control of the haemorrhage with local haemostatic measures. However, new antiplatelet drugs protocols are not firmly established. CONCLUSIONS: In spite of the existing recommendations, it is always advisable to consult with the internist or cardiologist of every patient before any intervention. Key words:Antiplatelet, Oral Surgery, Exodontia, Dental Management.

17.
ACS Nano ; 9(5): 4686-97, 2015 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-25938172

RESUMEN

Considerable progress in the synthesis and technology of hydrogels makes these materials attractive structures for designing controlled-release drug delivery systems. In particular, this review highlights the latest advances in nanocomposite hydrogels as drug delivery vehicles. The inclusion/incorporation of nanoparticles in three-dimensional polymeric structures is an innovative means for obtaining multicomponent systems with diverse functionality within a hybrid hydrogel network. Nanoparticle-hydrogel combinations add synergistic benefits to the new 3D structures. Nanogels as carriers for cancer therapy and injectable gels with improved self-healing properties have also been described as new nanocomposite systems.


Asunto(s)
Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Hidrogeles/química , Nanocompuestos/química , Nanopartículas/química , Polímeros/química , Humanos
18.
Int J Artif Organs ; 36(3): 159-65, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23404637

RESUMEN

A novel method for fabrication of branched, tubular, perfusable microvessels for use in vascular tissue engineering is reported. A tubular, elastomeric, biodegradable scaffold is first fabricated via a new, double fusible injection molding technique that uses a ternary alloy with a low melting temperature, Field's metal, and paraffin as sacrificial components. A cylindrical core metal of 500 µm or lower dia-meter with the target branching scaffold geometry is first constructed, then the metal structure is coated with paraffin and, finally, the metal-paraffin construct is embedded in polydimethylsiloxane (PDMS). The paraffin layer is then removed by heating and replaced by a biodegradable elastomeric pre-polymer that is subsequently UV-cured inside the PDMS. Next, the metal core is melted away and the PDMS is removed to attain the branched tubular elastomeric biodegradable scaffold. Finally, it is also demonstrated that human umbilical vein endothelial cells (HUVEC) were able to spread on the surface of the scaffold and form a confluent monolayer, confirming the potential of this new technique for making engineered blood vessels.


Asunto(s)
Microvasos , Ingeniería de Tejidos/métodos , Andamios del Tejido , Materiales Biocompatibles , Supervivencia Celular , Células Endoteliales de la Vena Umbilical Humana , Humanos , Polímeros
19.
J Food Sci ; 78(5): S777-84, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23574577

RESUMEN

The effect of sucrose replacement by erythritol and inulin was studied in short-dough cookies using instrumental and sensory analysis. Two levels of replacement were used (25% and 50% of total sucrose content). Descriptive sensory analysis showed that the sucrose replacement affects visual and texture cookies characteristics, being the differences perceived by mouth greater than by hand. In general, sucrose substitutes produced a less crispy cookie and lower consumer acceptability, with the exception of 25% sucrose replacement by inulin. Matrix aeration attributes such as open and crumbly obtained by trained panel were important properties, and correlated positively with consumer acceptance and negatively with maximum force at break (hardness). Inulin cookies sensory properties were more similar to the control than the erythritol cookies. Also, consumer overall acceptance decreased significantly with sucrose replacement by erythritol. The analysis of texture and sound revealed that inulin cookies were softer whereas erythritol cookies were harder in comparison with control cookies; despite this difference, inulin cookies had similar sound characteristics to erythritol cookies.


Asunto(s)
Eritritol/análisis , Inulina/análisis , Sacarosa/análisis , Comportamiento del Consumidor , Eritritol/química , Manipulación de Alimentos , Humanos , Inulina/química , Odorantes , Sacarosa/química , Gusto
20.
Int J Pharm ; 441(1-2): 468-75, 2013 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-23164705

RESUMEN

The use of injectable local anaesthetics for the treatment of severe postoperative pain is limited by the short duration of the painkilling effect. Pre-formulation studies were carried out for the development of an injectable microparticle formulation for controlled release of prilocaine, an amino-amide type local anaesthetic suitable for intravenous, subcutaneous and intramuscular administration. To the best of our knowledge, the encapsulation of prilocaine into microparticles has not been investigated yet. Three different poly-lactic-acid (PLA) polymers were separately employed for the preparation of the microparticles. Thermal analyses by differential scanning calorimetry (DSC) were carried out for the characterization of the raw materials, to assess the drug-polymer compatibility and miscibility, to investigate the effects of the production process on the components. Empty and prilocaine loaded microparticles were prepared by double emulsion method. All formulations were fully characterized in terms of drug content, morphology, size and in vitro drug release. The preliminary value of PRL solubility in the polymer material determined by DSC was evaluated and discussed as a predictive value for encapsulation efficiency and controlled release. DSC analysis turned out to be a usefulness tool for a fast polymer selection. Microparticles prepared with PLA R202 and R203S showed desirable characteristics for subcutaneous administration and could represent two promising formulations for the development of innovative pharmacological tools in the treatment of postoperative pain.


Asunto(s)
Anestésicos Locales/administración & dosificación , Portadores de Fármacos/química , Ácido Láctico/química , Polímeros/química , Prilocaína/administración & dosificación , Anestésicos Locales/química , Rastreo Diferencial de Calorimetría , Preparaciones de Acción Retardada , Composición de Medicamentos , Emulsiones , Inyecciones Intramusculares , Inyecciones Intravenosas , Inyecciones Subcutáneas , Microesferas , Dolor Postoperatorio/tratamiento farmacológico , Poliésteres , Prilocaína/química , Solubilidad
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