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1.
Int J Mol Sci ; 25(13)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38999953

RESUMEN

Hybrid scaffolds that are based on PLA and PLA/PMMA with 75/25, 50/50, and 25/75 weight ratios and functionalized with 10 wt.% of bioglass nanoparticles (n-BG) were developed using an electrospinning technique with a chloroform/dimethylformamide mixture in a 9:1 ratio for bone tissue engineering applications. Neat PLA and PLA/PMMA hybrid scaffolds were developed successfully through a (CF/DMF) solvent system, obtaining a random fiber deposition that generated a porous structure with pore interconnectivity. However, with the solvent system used, it was not possible to generate fibers in the case of the neat PMMA sample. With the increase in the amount of PMMA in PLA/PMMA ratios, the fiber diameter of hybrid scaffolds decreases, and the defects (beads) in the fiber structure increase; these beads are associated with a nanoparticle agglomeration, that could be related to a low interaction between n-BG and the polymer matrix. The Young's modulus of PLA/PMMA/n-BG decreases by 34 and 80%, indicating more flexible behavior compared to neat PLA. The PLA/PMMA/n-BG scaffolds showed a bioactive property related to the presence of hydroxyapatite crystals in the fiber surface after 28 days of immersion in a Simulated Body Fluids solution (SBF). In addition, the hydrolytic degradation process of PLA/PMMA/n-BG, analyzed after 35 days of immersion in a phosphate-buffered saline solution (PBS), was less than that of the pure PLA. The in vitro analysis using an HBOF-1.19 cell line indicated that the PLA/PMMA/n-BG scaffold showed good cell viability and was able to promote cell proliferation after 7 days. On the other hand, the in vivo biocompatibility evaluated via a subdermal model in BALC male mice corroborated the good behavior of the scaffolds in avoiding the generation of a cytotoxic effect and being able to enhance the healing process, suggesting that the materials are suitable for potential applications in tissue engineering.


Asunto(s)
Cerámica , Nanopartículas , Poliésteres , Polimetil Metacrilato , Ingeniería de Tejidos , Andamios del Tejido , Ingeniería de Tejidos/métodos , Poliésteres/química , Polimetil Metacrilato/química , Andamios del Tejido/química , Cerámica/química , Cerámica/farmacología , Nanopartículas/química , Animales , Ratones , Huesos/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Humanos , Línea Celular
2.
Int J Biol Macromol ; 273(Pt 1): 132891, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38848852

RESUMEN

Electrospun nanocomposite scaffolds with improved bioactive and biological properties were fabricated from a blend of polycaprolactone (PCL) and starch, and then combined with 5 wt% of calcium oxide (CaO) nanoparticles sourced from eggshells. SEM analyses showed scaffolds with fibrillar morphology and a three-dimensional structure. The hydrophilicity of scaffolds was improved with starch and CaO nanoparticles, which was evidenced by enhanced water absorption (3500 %) for 7 days. In addition, PCL/Starch/CaO scaffolds exhibited major degradation, with a mass loss of approximately 60 % compared to PCL/Starch and PCL/CaO. The PCL/Starch/CaO scaffolds decreased in crystallinity as intermolecular interactions between the nanoparticles retarded the mobility of the polymeric chains, leading to a significant increase in Young's modulus (ca. 60 %) and a decrease in tensile strength and elongation at break, compared to neat PCL. SEM-EDS, FT-IR, and XRD analyses indicated that PCL/Starch/CaO scaffolds presented a higher biomineralization capacity due to the ability to form hydroxyapatite (HA) in their surface after 28 days. The PCL/Starch/CaO scaffolds showed attractive biological performance, allowing cell adhesion and viability of M3T3-E1 preosteoblastic cells. In vivo analysis using a subdermal dorsal model in Wistar rats showed superior biocompatibility and improved resorption process compared to a pure PCL matrix. This biological analysis suggested that the PCL/Starch/CaO electrospun mats are suitable scaffolds for guiding the regeneration of bone tissue.


Asunto(s)
Huesos , Compuestos de Calcio , Nanopartículas , Óxidos , Poliésteres , Almidón , Ingeniería de Tejidos , Andamios del Tejido , Almidón/química , Poliésteres/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Nanopartículas/química , Óxidos/química , Compuestos de Calcio/química , Ratas , Ratones , Materiales Biocompatibles/química , Ratas Wistar , Línea Celular , Nanocompuestos/química
3.
PLoS One ; 19(5): e0302018, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38696406

RESUMEN

OBJECTIVE: The aim is to examine whether the addition of Virtual Reality (VR) meditation training to a standard 8-week Mindfulness-Based Health Care Program (MBHC-VR) results in a significantly increased improvement in occupational, mental health, and psychological functioning versus MBHC-only in university students. MATERIALS AND METHODS: A randomized controlled clinical trial with three arms (MBHC, MBHC-VR, Control Group), four assessment time points (pre-intervention, inter-session, post-intervention, and 3-month follow-up), and mixed methodology will be proposed. University students (undergraduate, master, or doctoral) interested in participating and who meet the inclusion/exclusion criteria will be included over two years. Data will be collected from different ad hoc questionnaires, several standardized tests, and an Ecological Momentary Assessment. We will use R software to carry out descriptive analyses (univariate and bivariate), multilevel modeling, and structural equation models to respond to the proposed objective. The qualitative analysis will be carried out using the MAXQDA program and the technique of focus groups. DISCUSSION: It is expected that with the proposed intervention university students will learn to relate in a healthier way with their mental processes, so as to improve their occupational balance (OB) and their psychological well-being. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT05929430.


Asunto(s)
Salud Mental , Atención Plena , Estudiantes , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Meditación/métodos , Meditación/psicología , Atención Plena/métodos , Estudiantes/psicología , Encuestas y Cuestionarios , Universidades , Realidad Virtual , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
Biomater Adv ; 153: 213578, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37572597

RESUMEN

Calcium oxide nanoparticles (n-CaO) ca. 22 nm were obtained from eggshell waste. The n-CaO was incorporated into the PLA matrix in 10 and 20 wt% of filler content by electrospinning process to get PLA/n-CaO fibers with homogenous morphology and diameter as a potential use in scaffold for bone tissue regeneration. The incorporation of n-CaO into PLA modifies the mechanical properties, having a reinforcement effect on the matrix. The Young modulus for PLA/n-CaO nanocomposites increased between 122 and 138 % concerning neat PLA fibers, showing a more rigid behavior. The PLA/n-CaO nanocomposite fibers showed in vitro bioactivity, capable of inducing the precipitation of hydroxyapatite (HA) layer in the fiber surface after seven days in SBF solution. The biocidal and biological properties of PLA/n-Cao with 20 wt% showed a 30 % reduction in bacterial viability against S. aureus and 11 % against E. coli after 6 h of bacterial exposure. Furthermore, the fibers did not show a cytotoxic effect on the bone marrow ST-2 cell line, allowing cell adhesion and proliferation in the RPMI medium. The PLA/n-CaO with 20 wt% of nanoparticles showed a higher capacity to promote osteogenic differentiation, significantly increasing the alkaline phosphatase (ALP) expression after seven days compared to PLA and cell control. The in vivo analysis corroborated the biocompatibility of the prepared scaffolds; the presence of n-CaO in PLA reduced the formation of fibrous encapsulation of the material, improving the healing process. These results validated using n-CaO to enhance the functionality of polymer matrices as a PLA, bringing bioactive, biocide, and biocompatible properties, opening a new and interesting route to develop new biomaterials as a scaffold for bone tissue engineering.


Asunto(s)
Nanocompuestos , Nanocompuestos/química , Electrones , Huesos/química , Staphylococcus aureus , Escherichia coli , Animales , Ratones , Línea Celular , Supervivencia Celular , Andamios del Tejido
6.
Polymers (Basel) ; 15(5)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36904322

RESUMEN

The development of scaffolding obtained by electrospinning is widely used in tissue engineering due to porous and fibrous structures that can mimic the extracellular matrix. In this study, poly (lactic-co-glycolic acid) (PLGA)/collagen fibers were fabricated by electrospinning method and then evaluated in the cell adhesion and viability of human cervical carcinoma HeLa and NIH-3T3 fibroblast for potential application in tissue regeneration. Additionally, collagen release was assessed in NIH-3T3 fibroblasts. The fibrillar morphology of PLGA/collagen fibers was verified by scanning electron microscopy. The fiber diameter decreased in the fibers (PLGA/collagen) up to 0.6 µm. FT-IR spectroscopy and thermal analysis confirmed that both the electrospinning process and the blend with PLGA give structural stability to collagen. Incorporating collagen in the PLGA matrix promotes an increase in the material's rigidity, showing an increase in the elastic modulus (38%) and tensile strength (70%) compared to pure PLGA. PLGA and PLGA/collagen fibers were found to provide a suitable environment for the adhesion and growth of HeLa and NIH-3T3 cell lines as well as stimulate collagen release. We conclude that these scaffolds could be very effective as biocompatible materials for extracellular matrix regeneration, suggesting their potential applications in tissue bioengineering.

7.
Int J Biol Macromol ; 228: 78-88, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36565827

RESUMEN

Electrospun scaffolds based on poly(l-lactic acid) (PLLA) with bioglass (n-BG) and zinc oxide (n-ZnO), and mixture of both, were developed to design bifunctional biomaterials with enhanced bioactive and biocidal properties. The presence of n-BG increased the fiber diameter of the pure PLA from 1.5 ± 0.3 µm to 3.0 ± 0.8 µm for 20 wt%. ZnO and the mixed nanoparticles did not significantly affect the morphology. The mechanical properties decreased with the presence of nanoparticles. Scaffolds based on PLA/n-BG promoted hydroxyapatite (HA) formation in simulated body fluid (SBF) that was inhibited with the presence of ZnO. Notably, mixed particles produced bioactivity although at longer times. The incorporation of n-ZnO produced a biocidal capacity against S. aureus in the polymeric scaffold, reaching a viability reduction of 60 % after 6 h of exposure. When both types of nanoparticles were combined, the bacterial viability reduction was 30 %. Pure PLA scaffolds and the composites with n-BG showed good ST-2 bone marrow-derived cell line viability, scaffolds with n-BG (pure or mixture) presented lower viability. Results validated the use of both n-BG and n-ZnO fillers for the development of novel bifunctional PLA-based scaffolds with both bioactive and biocidal properties for bone tissue engineering applications.


Asunto(s)
Nanopartículas , Óxido de Zinc , Ingeniería de Tejidos/métodos , Andamios del Tejido , Staphylococcus aureus , Poliésteres
8.
Polymers (Basel) ; 16(1)2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-38201794

RESUMEN

Polymer-based nanocomposites such as polycaprolactone/graphene oxide (PCL/GO) have emerged as alternatives for bone tissue engineering (BTE) applications. The objective of this research was to investigate the impact of a gelatin (Gt) coating on the degradability and different properties of PCL nanofibrous scaffolds fabricated by an electrospinning technique with 1 and 2 wt% GO. Uniform PCL/GO fibers were obtained with a beadless structure and rough surface. PCL/GO scaffolds exhibited an increase in their crystallization temperature (Tc), attributed to GO, which acted as a nucleation agent. Young's modulus increased by 32 and 63% for the incorporation of 1 and 2 wt% GO, respectively, in comparison with neat PCL. A homogeneous Gt coating was further applied to these fibers, with incorporations as high as 24.7 wt%. The introduction of the Gt coating improved the hydrophilicity and degradability of the scaffolds. Bioactivity analysis revealed that the hydroxyapatite crystals were deposited on the Gt-coated scaffolds, which made them different from their uncoated counterparts. Our results showed the synergic effect of Gt and GO in enhancing the multifunctionality of the PCL, in particular the degradability rate, bioactivity, and cell adhesion and proliferation of hGMSC cells, making it an interesting biomaterial for BTE.

9.
Int J Biol Macromol ; 210: 324-336, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35545139

RESUMEN

Electrospun fibers of poly (lactic acid) (PLA) containing 10 and 20 wt% of bioactive glass (n-BG) and magnesium oxide (n-MgO) nanoparticles of ca. 27 and 23 nm respectively, were prepared toward to application in bone tissue engineering. The addition of both nanoparticles into the PLA will produce a synergic effect increasing its bioactivity and antimicrobial behavior. Neat PLA scaffold and the composites with MgO showed an average fiber diameter of 1.7 ± 0.6 µm, PLA/n-BG and PLA/n-BG/n-MgO fibers presented a significant diameter increase reaching values of ca. 3.1 ± 0.8 µm. Young's modulus of the electrospun scaffolds was affected by the direct presence of the particle and scaffold morphologies. All the composites having n-BG presented bioactivity through the precipitation of hydroxyapatite structures on the surface. Although n-MgO did not add bioactivity to the PLA fibers, they were able to render antimicrobial characteristics reducing the S. aureus viability around 30%, although an effect on E. coli strain was not observed. PLA/n-BG nanocomposites did not display any significant antimicrobial behavior. The different composites increased the alkaline phosphatase (ALP) expression as compared with pure PLA barely affecting the cell viability, meaning a good osteoblastic phenotype expression capacity, with PLA/n-BG presenting the highest osteoblastic expression.


Asunto(s)
Óxido de Magnesio , Nanopartículas , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regeneración Ósea , Escherichia coli/metabolismo , Vidrio/química , Ácido Láctico/química , Óxido de Magnesio/farmacología , Nanopartículas/química , Poliésteres/química , Staphylococcus aureus/metabolismo , Ingeniería de Tejidos , Andamios del Tejido/química
10.
Healthcare (Basel) ; 10(3)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35327020

RESUMEN

A person affected by Alzheimer's disease (AD) gradually loses the ability to perform activities of daily living and becomes dependent on caregivers, thereby having a negative impact on the caregivers' quality of life. There is evidence that suggests that interventions aimed at caregivers, such as mindfulness, may be effective at reducing this burden and emotional issues, such as depression and anxiety, and improving their quality of life. However, there is a lack of consistency in the findings and conclusions remain tentative. In addition, as neuropsychiatric symptoms (NPSs) of AD are major determinants of the caregiver's burden, these interventions should examine the relationship between these symptoms and caregiver outcomes. Importantly, to improve the design of therapeutic interventions for caregivers and complement the treatment of AD, aspects related to occupational performance and the participation of people with AD and their caregivers should also be considered. Therefore, this study will aim to examine first, the effects of a mindfulness-based program designed for caregivers on NPSs of AD and caregivers' anxiety and depression; second, the effects of this program on patients' functional capacity, cognitive performance, executive functions, and quality of life, and on caregivers' burden, quality of life, occupational balance, executive functions, psychological wellbeing, and self-compassion. We believe that the findings of this study will have significant implications for future healthcare strategies focused on improving the quality of life and wellbeing of caregivers.

11.
Polymers (Basel) ; 12(9)2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-32961957

RESUMEN

Low-density polyethylene composites containing different sizes of calcium oxide (CaO) nanoparticles were obtained by melt mixing. The CaO nanoparticles were synthesized by either the sol-gel or sonication methods, obtaining two different sizes: ca. 55 nm and 25 nm. These nanoparticles were used either as-synthesized or were modified organically on the surface with oleic acid (Mod-CaO), at concentrations of 3, 5, and 10 wt% in the polymer. The Mod-CaO nanoparticles of 25 nm can act as nucleating agents, increasing the polymer's crystallinity. The Young's Modulus increased with the Mod-CaO nanoparticles, rendering higher reinforcement effects with an increase as high as 36%. The reduction in Escherichia coli bacteria in the nanocomposites increased with the amount of CaO nanoparticles, the size reduction, and the surface modification. The highest antimicrobial behavior was found in the composites with a Mod-CaO of 25 nm, presenting a reduction of 99.99%. This strong antimicrobial effect can be associated with the release of the Ca2+ from the composites, as studied for the composite with 10 wt% nanoparticles. The ion release was dependent on the size of the nanoparticles and their surface modification. These findings show that CaO nanoparticles are an excellent alternative as an antimicrobial filler in polymer nanocomposites to be applied for food packaging or medical devices.

12.
J Biomed Mater Res A ; 108(10): 2032-2043, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32333463

RESUMEN

Bioglass nanoparticles (n-BGs, 54SiO2 :40CaO:6P2 O5 mol %) with about 27 nm diameter were synthesized by the sol-gel method and incorporated into a poly(lactic acid) (PLA) matrix by the melting process in order to obtain nanocomposites with filler contents of 5, 10, and 25 wt %. Our results showed that during the cooling scan, the crystallization temperature (Tc ) of the PLA/n-BG nanocomposites decreased 13°C as compared to neat PLA. The presence of nanoparticles also decreased the thermal stability of the PLA matrix, as nanocomposites presented up to about 20°C lower degradation temperatures in a nitrogen atmosphere. The presence of n-BG increased the stiffness of the polymer matrix, and for instance the composite with 25 wt % of filler presented about 52.6% higher Young's modulus than neat PLA. n-BG incorporation into PLA increased also the hydrolytic degradation of the polymer over time. When the PLA composites were immersed in simulated body fluid, an apatite layer was formed on their surface, as verified by Fourier transform infrared, X-Ray Diffraction (XRD), and scanning electron microscopy-EDS, showing that the presence of n-BG induced bioactivity on the PLA matrix. Moreover, the viability of cervical uterine adenocarcinoma cells was higher on PLA/n-BG nanocomposite with 25 wt % of filler. The presence of n-BG barely gave an antibacterial effect on the polymer matrix, despite the well-known biocidal properties of these nanoparticles. Our results show that the presence of n-BGs is a proper route for improving the bioactivity of PLA with potential application in tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Cerámica/química , Nanopartículas/química , Poliésteres/química , Materiales Biocompatibles/farmacología , Supervivencia Celular/efectos de los fármacos , Cerámica/farmacología , Cristalización , Módulo de Elasticidad , Células HeLa , Humanos , Nanocompuestos/química , Poliésteres/farmacología
13.
Int J Med Sci ; 15(9): 883-891, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30008600

RESUMEN

Background: Diagnosis of malignant pleural mesothelioma (MPM) remains a challenge, especially when resources in pathology are limited. The study aimed to evaluate cost-effective tumor markers to predict the probability of MPM in plasma samples in order to accelerate the diagnostic workup of the tissue of potential cases. Methods: We conducted a case-control study stratified by gender, which included 75 incident cases with MPM from three Mexican hospitals and 240 controls frequency-matched by age and year of blood drawing. Plasma samples were obtained to determine mesothelin, calretinin, and thrombomodulin using enzyme-linked immunosorbent assays (ELISAs). We estimated the performance of the markers based on the area under the curve (AUC) and predicted the probability of an MPM diagnosis of a potential case based on the marker concentrations. Results: Mesothelin and calretinin, but not thrombomodulin were significant predictors of a diagnosis of MPM with AUCs of 0.90 (95% CI: 0.85-0.95), 0.88 (95% CI: 0.82-0.94), and 0.51 (95% CI: 0.41-0.61) in males, respectively. For MPM diagnosis in men we estimated a true positive rate of 0.79 and a false positive rate of 0.11 for mesothelin. The corresponding figures for calretinin were 0.81 and 0.18, and for both markers combined 0.84 and 0.11, respectively. Conclusions: We developed prediction models based on plasma concentrations of mesothelin and calretinin to estimate the probability of an MPM diagnosis. Both markers showed a good performance and could be used to accelerate the diagnostic workup of tissue samples in Mexico.


Asunto(s)
Biomarcadores de Tumor/análisis , Calbindina 2/sangre , Proteínas Ligadas a GPI/sangre , Mesotelioma/diagnóstico , Neoplasias Pleurales/diagnóstico , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Neoplasias Pulmonares , Masculino , Mesotelina , Mesotelioma/sangre , México , Persona de Mediana Edad , Neoplasias Pleurales/sangre
16.
IEEE Trans Biomed Circuits Syst ; 10(5): 979-989, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27654976

RESUMEN

A new wireless electrophysiology data acquisition system, built around a standard homecage, is presented in this paper, which can power up and communicate with sensors and actuators/stimulators attached to or implanted in small freely behaving animal subjects, such as rodents. Key abilities of the energized homecage (EnerCage) system is enabling longitudinal experiments with minimal operator involvement or interruption, while providing test subjects with an enriched environment closer to their natural habitat, without the burden of being tethered or carrying bulky batteries. The magnetic resonant multi-coil design used in the new EnerCage-HC2 automatically localizes the transmitted electromagnetic power from a single transmitter (Tx) coil at the bottom of the cage toward the receiver coil (Rx), carried on/in the animal body, obviating the need for tracking the animal or switching the coils. In order to increase the resonators' quality factor (Q > 166) at the desired operating frequency of 13.56 MHz, while maintaining a high self-resonance frequency [Formula: see text], they are made of wide copper foils and optimally segmented based on a set of design rules that can be adopted for experimental arenas with different shapes and dimensions. The Rx rectified voltage is regulated at a user-defined window [Formula: see text] by a Tx-Rx closed-loop power control (CLPC) mechanism that creates a volume inside the homecage with 42 mW of power delivered to the load (PDL), and a homogeneous power transfer efficiency (PTE) plane of 14% on average at ∼7 cm height, plus stability against angular mis-alignments of up to 80°.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/veterinaria , Suministros de Energía Eléctrica/veterinaria , Vivienda para Animales , Monitoreo Ambulatorio/instrumentación , Monitoreo Ambulatorio/veterinaria , Tecnología Inalámbrica/instrumentación , Animales , Cobre , Diseño de Equipo , Análisis de Falla de Equipo , Retroalimentación , Miniaturización
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 6323-6326, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28269695

RESUMEN

This paper presents a new EnerCage-homecage system, EnerCage-HC2, for longitudinal electrophysiology data acquisition experiments on small freely moving animal subjects, such as rodents. EnerCage-HC2 is equipped with multi-coil wireless power transmission (WPT), closed-loop power control, bidirectional data communication via Bluetooth Low Energy (BLE), and Microsoft Kinect® based animal behavior tracking and analysis. The EnerCage-HC2 achieves a homogeneous power transfer efficiency (PTE) of 14% on average, with ~42 mW power delivered to the load (PDL) at a nominal height of 7 cm by the closed-loop power control mechanism. The Microsoft Kinect® behavioral analysis algorithm can not only track the animal position in real-time but also classify 5 different types of rodent behaviors: standstill, walking, grooming, rearing, and rotating. A proof-of-concept in vivo experiment was conducted on two awake freely behaving rats while successfully operating a one-channel stimulator and generating an ethogram.


Asunto(s)
Conducta Animal , Suministros de Energía Eléctrica , Tecnología Inalámbrica , Algoritmos , Animales , Masculino , Ratas
18.
Mater Sci Eng C Mater Biol Appl ; 57: 314-20, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26354270

RESUMEN

Poly(lactic acid) (PLA) composites with titanium oxide (TiO2) ~10-nm nanoparticles were produced by the melting process and their main properties were evaluated. The nanoparticles are homogeneously dispersed in the matrix with a low degree of agglomeration, as seen by transmission electron microscopy (TEM). The crystallinity temperature increased ~12% when 5 wt.% of TiO2 was added, showing that the nanoparticles acted as nucleating agents this trend was confirmed by optical images. The elastic modulus increased ~54% compared to neat PLA at 5 wt.% of nanoparticles. Despite these improvements, PLA/TiO2 nanocomposites showed lower shear viscosity than neat PLA, possibly reflecting degradation of the polymer due to the particles. Regarding biocidal properties, after 2h of contact the PLA/TiO2 composites with 8 wt.% TiO2 showed a reduction of Escherichia coli colonies of ~82% under no UVA irradiation compared to pure PLA. This biocidal characteristic can be increased under UVA irradiation, with nanocomposites containing 8 wt.% TiO2 killing 94% of the bacteria. The PLA/TiO2 nanocomposites with 8 wt.% were also 99.99% effective against Aspergillus fumigatus under the UVA irradiation.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Ácido Láctico/química , Polímeros/química , Titanio/farmacología , Antibacterianos/síntesis química , Antifúngicos/síntesis química , Supervivencia Celular/efectos de los fármacos , Escherichia coli/fisiología , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , Nanocápsulas/administración & dosificación , Nanocápsulas/química , Nanocápsulas/ultraestructura , Nanocompuestos/administración & dosificación , Nanocompuestos/química , Poliésteres , Titanio/química
19.
Arch. bronconeumol. (Ed. impr.) ; 49(10): 447-449, oct. 2013. ilus
Artículo en Español | IBECS | ID: ibc-129128

RESUMEN

Mujer de 21 años diagnosticada de cirrosis criptogénica desde los 9 años de edad, que presentó empiema izquierdo posneumónico que no remitió con el tratamiento médico convencional y evolucionó con fistulización hacia la piel en el séptimo espacio intercostal a nivel subescapular izquierdo. Se realizó una ventana torácica abierta y al sexto día se envió a su domicilio con colocación de sistema cerrado de succión portátil, con cambios cada 4 días del material hasta la obliteración total de la cavidad (92 días). Se observó por imagen una expansión completa del pulmón y se realizó reconstrucción de la pared torácica con barras de titanio. La alta mortalidad del empiema, en los pacientes con hepatopatías, requiere la implementación y la búsqueda de nuevas terapias adyuvantes, como la utilización del sistema cerrado de succión y la reconstrucción con barras de titanio. Para una adecuada evaluación, se requieren estudios controlados con una serie de casos amplia (AU)


The patient is a 21-year-old female, diagnosed with cryptogenic cirrhosis at the age of 9. She presented with left post-pneumonic empyema that did not remit with conventional medical management and evolved with fistulization to the skin in the 7th intercostal space in the left subscapular region. We performed an open thoracic window procedure, and on the 6th day the patient was sent home with a portable vacuum-assisted closure device, with changes of the material every 4 days until the cavity was completed obliterated (92 days). Imaging tests showed full expansion of the lung, and chest wall reconstruction was performed with titanium rods. The high mortality of empyema in patients with liver disease requires both implementing and searching for new adjuvant therapies, like the use of vacuum-assisted closure systems and reconstruction with titanium rods. Controlled studies with a wide range of cases are needed for proper evaluation (AU)


Asunto(s)
Humanos , Femenino , Adulto Joven , Cirrosis Hepática/complicaciones , Empiema Pleural/cirugía , Procedimientos Quirúrgicos Torácicos/métodos , Procedimientos de Cirugía Plástica/métodos , Succión/métodos
20.
Arch Bronconeumol ; 49(10): 447-9, 2013 Oct.
Artículo en Inglés, Español | MEDLINE | ID: mdl-23312986

RESUMEN

The patient is a 21-year-old female, diagnosed with cryptogenic cirrhosis at the age of 9. She presented with left post-pneumonic empyema that did not remit with conventional medical management and evolved with fistulization to the skin in the 7th intercostal space in the left subscapular region. We performed an open thoracic window procedure, and on the 6th day the patient was sent home with a portable vacuum-assisted closure device, with changes of the material every 4 days until the cavity was completed obliterated (92 days). Imaging tests showed full expansion of the lung, and chest wall reconstruction was performed with titanium rods. The high mortality of empyema in patients with liver disease requires both implementing and searching for new adjuvant therapies, like the use of vacuum-assisted closure systems and reconstruction with titanium rods. Controlled studies with a wide range of cases are needed for proper evaluation.


Asunto(s)
Empiema Pleural/cirugía , Cirrosis Hepática/complicaciones , Terapia de Presión Negativa para Heridas , Procedimientos de Cirugía Plástica/métodos , Infecciones Estafilocócicas/cirugía , Staphylococcus haemolyticus/aislamiento & purificación , Pared Torácica/cirugía , Antibacterianos/uso terapéutico , Terapia Combinada , Fístula Cutánea/etiología , Drenaje , Empiema Pleural/tratamiento farmacológico , Empiema Pleural/etiología , Empiema Pleural/microbiología , Femenino , Volumen Espiratorio Forzado , Humanos , Terapia de Presión Negativa para Heridas/instrumentación , Osteomielitis/etiología , Osteomielitis/microbiología , Osteomielitis/cirugía , Derrame Pleural/etiología , Neumonía/complicaciones , Neumonía/tratamiento farmacológico , Prótesis e Implantes , Atelectasia Pulmonar/etiología , Costillas/microbiología , Costillas/cirugía , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/etiología , Capacidad Vital , Adulto Joven
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