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1.
Int J Nanomedicine ; 19: 3423-3440, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617800

RESUMO

Introduction: Osteoporotic-related fractures remains a significant public health concern, thus imposing substantial burdens on our society. Excessive activation of osteoclastic activity is one of the main contributing factors for osteoporosis-related fractures. While polylactic acid (PLA) is frequently employed as a biodegradable scaffold in tissue engineering, it lacks sufficient biological activity. Microdroplets (MDs) have been explored as an ultrasound-responsive drug delivery method, and mesenchymal stem cell (MSC)-derived exosomes have shown therapeutic effects in diverse preclinical investigations. Thus, this study aimed to develop a novel bioactive hybrid PLA scaffold by integrating MDs-NFATc1-silencing siRNA to target osteoclast formation and MSCs-exosomes (MSC-Exo) to influence osteogenic differentiation (MDs-NFATc1/PLA-Exo). Methods: Human bone marrow-derived mesenchymal stromal cells (hBMSCs) were used for exosome isolation. Transmission electron microscopy (TEM) and confocal laser scanning microscopy were used for exosome and MDs morphological characterization, respectively. The MDs-NFATc1/PLA-Exo scaffold was fabricated through poly(dopamine) and fibrin gel coating. Biocompatibility was assessed using RAW 264.7 macrophages and hBMSCs. Osteoclast formations were examined via TRAP staining. Osteogenic differentiation of hBMSCs and cytokine expression modulation were also investigated. Results: MSC-Exo exhibited a cup-shaped structure and effective internalization into cells, while MDs displayed a spherical morphology with a well-defined core-shell structure. Following ultrasound stimulation, the internalization study demonstrated efficient delivery of bioactive MDs into recipient cells. Biocompatibility studies indicated no cytotoxicity of MDs-NFATc1/PLA-Exo scaffolds in RAW 264.7 macrophages and hBMSCs. Both MDs-NFATc1/PLA and MDs-NFATc1/PLA-Exo treatments significantly reduced osteoclast differentiation and formation. In addition, our results further indicated MDs-NFATc1/PLA-Exo scaffold significantly enhanced osteogenic differentiation of hBMSCs and modulated cytokine expression. Discussion: These findings suggest that the bioactive MDs-NFATc1/PLA-Exo scaffold holds promise as an innovative structure for bone tissue regeneration. By specifically targeting osteoclast formation and promoting osteogenic differentiation, this hybrid scaffold may address key challenges in osteoporosis-related fractures.


Assuntos
Exossomos , Osteoporose , Humanos , RNA Interferente Pequeno/genética , Osteogênese , Porosidade , Poliésteres , Citocinas , Osteoporose/terapia
2.
Nat Commun ; 15(1): 3131, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605012

RESUMO

Reconciling the dilemma between rapid degradation and overdose toxicity is challenging in biodegradable materials when shifting from bulk to porous materials. Here, we achieve significant bone ingrowth into Zn-based porous scaffolds with 90% porosity via osteoinmunomodulation. At microscale, an alloy incorporating 0.8 wt% Li is employed to create a eutectoid lamellar structure featuring the LiZn4 and Zn phases. This microstructure optimally balances high strength with immunomodulation effects. At mesoscale, surface pattern with nanoscale roughness facilitates filopodia formation and macrophage spreading. At macroscale, the isotropic minimal surface G unit exhibits a proper degradation rate with more uniform feature compared to the anisotropic BCC unit. In vivo, the G scaffold demonstrates a heightened efficiency in promoting macrophage polarization toward an anti-inflammatory phenotype, subsequently leading to significantly elevated osteogenic markers, increased collagen deposition, and enhanced new bone formation. In vitro, transcriptomic analysis reveals the activation of JAK/STAT pathways in macrophages via up regulating the expression of Il-4, Il-10, subsequently promoting osteogenesis.


Assuntos
Osteogênese , Tecidos Suporte , Osteogênese/fisiologia , Tecidos Suporte/química , Porosidade , Impressão Tridimensional , Zinco/farmacologia
3.
J Colloid Interface Sci ; 665: 1065-1078, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38579389

RESUMO

Reactive oxygen species (ROS)-centered chemodynamic therapy (CDT) holds significant potential for tumor-specific treatment. However, insufficient endogenous H2O2 and extra glutathione within tumor microenvironment (TME) severely deteriorate the CDT's effectiveness. Herein, rich-Zn-Co3O4/N-doped porous carbon (Zn-Co3O4/NC) was fabricated by two-step pyrolysis, and applied to build high-efficiency nano-platform for synergistic cancer therapy upon combination with glucose oxidase (GOx), labeled Zn-Co3O4/NC-GOx for clarity. Specifically, the multiple enzyme-like activities of the Zn-Co3O4/NC were scrutinously investigated, including peroxidase-like activity to convert H2O2 to O2∙-, catalase-like activity to decompose H2O2 into O2, and oxidase-like activity to transform O2 to O2∙-, which achieved the CDT through the catalytic cascade reaction. Simultaneously, GOx reacted with intracellular glucose to produce gluconic acid and H2O2, realizing starvation therapy. In the acidic TME, the Zn-Co3O4/NC-GOx rapidly caused intracellular Zn2+ pool overload and disrupted cellular homeostasis for ion-intervention therapy. Additionally, the Zn-Co3O4/NC exhibited glutathione peroxidase-like activity, which consumed glutathione in tumor cells and reduced the ROS consumption for ferroptosis. The tumor treatments offer some constructive insights into the nanozyme-mediated catalytic medicine, coupled by avoiding the TME limitations.


Assuntos
Cobalto , Peróxido de Hidrogênio , Neoplasias , Óxidos , Humanos , Porosidade , Espécies Reativas de Oxigênio , Glucose Oxidase , Imidazóis , Carbono , Glutationa , Zinco , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral
4.
Mikrochim Acta ; 191(5): 262, 2024 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613581

RESUMO

Rapid and sensitive detection of carcinoembryonic antigen (CEA) is of great significance for cancer patients. Here, molybdenum (Mo) was doped into bismuth oxide (Bi2O3) by one-pot hydrothermal method forming porous tremella Bi2MoO6 nanocomposites with a larger specific surface area than the spherical structure. Then, a new kind of hydrangea-like TiO2/Bi2MoO6 porous nanoflowers (NFs) was prepared by doping titanium into Bi2MoO6, where titanium dioxide (TiO2) grew in situ on the surface of Bi2MoO6 nanoparticles (NPs). The hydrangea-like structure provides larger specific surface area, higher electron transfer ability and biocompatibility as well as more active sites conducive to the attachment of anti-carcinoembryonic antigen (anti-CEA) to TiO2/Bi2MoO6 NFs. A novel label-free electrochemical immunosensor was then constructed for the quantitative detection of CEA using TiO2/Bi2MoO6 NFs as sensing platform, showing a good linear relationship with CEA in the concentration range 1.0 pg/mL ~ 1.0 mg/mL and a detection limit of 0.125 pg/mL (S/N = 3). The results achieved with the designed immunosensor are comparable with many existing immunosensors used for the detection of CEA in real samples.


Assuntos
Técnicas Biossensoriais , Bismuto , Hydrangea , Molibdênio , Humanos , Biomarcadores Tumorais , Antígeno Carcinoembrionário , Porosidade , Imunoensaio
5.
Med Eng Phys ; 126: 104159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38621833

RESUMO

Generation of polyethylene wear debris and peri­prosthetic bone resorption have been identified as potential causes of acetabular component loosening in Total Hip Arthroplasty. This study was aimed at optimization of a functionally graded porous acetabular component to minimize peri­prosthetic bone resorption and polyethylene liner wear. Porosity levels (porosity values at acetabular rim, and dome) and functional gradation exponents (radial and polar) were considered as the design parameters. The relationship between porosity and elastic properties were obtained from numerical homogenization. The multi-objective optimization was carried out using a non-dominated sorting genetic algorithm integrated with finite element analysis of the hemipelvises subject to various loading conditions of common daily activities. The optimal functionally graded porous designs (OFGPs -1, -2, -3, -4, -5) exhibited less strain-shielding in cancellous bone compared to solid metal-backing. Maximum bone-implant interfacial micromotions (63-68 µm) for OFGPs were found to be close to that of solid metal-backing (66 µm), which might facilitate bone ingrowth. However, OFGPs exhibited an increase in volumetric wear (3-10 %) compared to solid metal-backing. The objective functions were found to be more sensitive to changes in polar gradation exponent than radial gradation exponent, based on the Sobol' method. Considering the common failure mechanisms, OFGP-1, having highly porous acetabular rim and less porous dome, appears to be a better alternative to the solid metal-backing.


Assuntos
Artroplastia de Quadril , Reabsorção Óssea , Prótese de Quadril , Humanos , Porosidade , Acetábulo/cirurgia , Metais , Polietileno , Reabsorção Óssea/cirurgia , Algoritmos , Desenho de Prótese , Falha de Prótese
6.
Med Eng Phys ; 126: 104160, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38621842

RESUMO

In this study, amino-functionalized mesoporous silica/hydroxyapatite nanoparticles (MSNS/HAP) with the property of acid dissociation have been prepared as a traditional Chinese medicine monomer carriers to improve the drug loading rate and antibacterial properties of antimicrobial quercetin (QUE) in vitro. The experimental results confirm that the drug loading rate of MSNs/HAP is 28.94 %, which is about 3.6 times higher than that of aminated mesoporous sililca nanoparticles (MSNs). The drug release of QUE on MSNs/HAP is pH-sensitive in phosphate buffered saline (pH=4.0-7.4). The above fabricated traditional Chinese medicine monomer modified nanocomposites (QUE@MSNs/HAP) displays concentration-dependent inhibitory effect, which shows better antibacterial effect than free QUE. The minimum inhibitory concentration for two tested bacteria, Staphylococcus aureus (S.aureus) and Escherichia coli (E.coli), is 256 mg·L -1. In summary, QUE@MSNs/HAP have successfully prepared, which not only improves the bio-availability of QUE, but also has acid-sensitive drug release properties. Compared with free QUE, its antibacterial performance significantly enhances, which provides a theoretical basis for the application of Chinese medicine molecules in bacterial treatment.


Assuntos
Durapatita , Nanopartículas , Quercetina/farmacologia , Dióxido de Silício/farmacologia , Antibacterianos/farmacologia , Porosidade , Portadores de Fármacos
7.
Chemosphere ; 355: 141890, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38575085

RESUMO

The co-transport behavior of environmental pollutants with biochar particles has aroused great interests from researchers due to the concerns about pollutant diffusion and environmental exposure after biochar is applied to soil. In this work, the recovery and co-transport behavior of biochar micron-/nano-particles (BCMP and BCNP) and lead (Pb2+) in saturated porous media were investigated under different ionic strength conditions (IS = 1, 5 and 10 mM) under a direct current electric field. The results showed that the electric field could significantly enhance the mobility of Pb adsorbed biochar particles, particularly BCNP. The recovery of Pb laden biochar particles was improved by 1.8 folds, reaching 78.8% at maximum under favorable condition at +0.5 V cm-1. According to the CDE (Convection-Dispersion-Equation) model and DLVO (Derjaguin-Landau-Verwey-Overbeek) theory analysis, the electric field facilitated the transport of Pb carried biochar mainly by increasing the negative charges on biochar surface and improving the repulsive force between biochar and porous media. High IS was favorable for biochar transport under the electric field, but inhibited desorbing Pb2+ from biochar (18% by maximum at IS = 10 mM). By switching the electric field power, a two-stage strategy was established to maximize the recovery of both biochar particles and Pb, where BCNP and Pb recovery were higher than electric field free case by 90% and 35%, respectively. The findings of this study can help build a biochar recovery approach to prevent potential risks from biochar application in heavy metal contaminated soil remediation.


Assuntos
Poluentes Ambientais , Poluentes do Solo , Chumbo , Porosidade , Carvão Vegetal , Solo , Poluentes do Solo/análise
8.
Mikrochim Acta ; 191(5): 231, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565795

RESUMO

Blood stasis syndrome (BSS) has persistent health risks; however, its pathogenesis remains elusive. This obscurity may result in missed opportunities for early intervention, increased susceptibility to chronic diseases, and reduced accuracy and efficacy of treatments. Metabolomics, employing the matrix-assisted laser desorption/ionization (MALDI) strategy, presents distinct advantages in biomarker discovery and unraveling molecular mechanisms. Nonetheless, the challenge is to develop efficient matrices for high-sensitivity and high-throughput analysis of diverse potential biomarkers in complex biosamples. This work utilized nitrogen-doped porous transition metal carbides and nitrides (NP-MXene) as a MALDI matrix to delve into the molecular mechanisms underlying BSS pathogenesis. Structural optimization yielded heightened peak sensitivity (by 1.49-fold) and increased peak numbers (by 1.16-fold) in clinical biosamples. Validation with animal models and clinical serum biosamples revealed significant differences in metabolic fingerprints between BSS and control groups, achieving an overall diagnostic efficacy of 0.905 (95% CI, 0.76-0.979). Prostaglandin F2α was identified as a potential biomarker (diagnostics efficiency of 0.711, specificity = 0.7, sensitivity = 0.6), and pathway enrichment analysis disclosed disruptions in arachidonic acid metabolism in BSS. This innovative approach not only advances comprehension of BSS pathogenesis, but also provides valuable insights for personalized treatment and diagnostic precision.


Assuntos
Medicamentos de Ervas Chinesas , Animais , Dinoprosta , Retroalimentação , Nitrogênio , Porosidade , Compostos Orgânicos , Biomarcadores
9.
Water Sci Technol ; 89(6): 1526-1538, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38557716

RESUMO

Water scarcity is a major global challenge that affects both developed and developing countries, with Indonesia serving as a prime example. Indonesia's archipelagic nature, combined with its dense population, exacerbates the severity of water scarcity. The increased population density in these areas raises the demand for water resources, putting a strain on the available supply. The purpose of this research was to create porous mortar filters (PMFs) with different ratios (1:4, 1:5, and 1:6) by incorporating 10, 15, and 20% adsorbent material by weight of fine aggregate. The research was carried out in three stages: determining PMF properties, preparing synthetic wastewater, and assessing treatment effectiveness. Various PMF compositions consistently achieved notable success, with reductions in total dissolved solids and turbidity exceeding 25 and 75%, respectively. The PMF performed admirably in eliminating bacterial concentrations, achieving a 100% removal rate, and was critical in efficiently reducing metals, with compositions achieving over 80% reduction for manganese (Mn) and 38% reduction for iron (Fe). PMF emerges as a practical solution as a cost-effective and simple water treatment technology, particularly suitable for areas with limited technological infrastructure and resources, providing accessible water treatment for communities facing challenges in this regard.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Porosidade , Águas Residuárias , Ferro/química , Manganês
10.
Environ Geochem Health ; 46(5): 153, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587707

RESUMO

The environmental fate and risks of ciprofloxacin (CIP) in the subsurface have raised intensive concerns. Herein, the transport behaviors of CIP in both saturated quartz sand and sand/multi-walled carbon nanotubes (MWCNTs) mixtures under different solution ionic strength of the solution and coexisting cation types were investigated. Batch adsorption experiments highlighted growing adsorptive capacity for CIP with the increasing content of MWCNTs in the MWCNTs-quartz sand mixtures (from 0.5% to 1.5%, w/w). Breakthrough curves (BTCs) of CIP in the MWCNTs-quartz sand mixtures were well fitted by the two-site chemical nonequilibrium model (R2 > 0.833). The estimated retardation factors for CIP increased from 9.68 to 282 with growing content of MWCNTs in the sand column, suggesting the presence of MWCNTs significantly inhibited the transport of CIP in saturated porous media. Moreover, the values of retardation factors are negatively correlated with the ionic strength and higher ionic strength could facilitate the transport of CIP in the saturated porous media. Compared with monovalent cations (Na+), the presence of divalent cations (Ca2+) significantly facilitated the transport of CIP in the columns due to the complexation between CIP and Ca2+ as well as deposition of MWCNTs aggregates on the sand surface. Results regarding CIP retention in columns indicated that MWCNTs could enhance the accumulation of CIP in the layers close to the influent of sand columns, while they could hinder upward transport of CIP to the effluent. This study improves our understanding for transport behaviors and environmental risk assessments of CIP in the saturated porous media with MWCNTs.


Assuntos
Nanotubos de Carbono , Porosidade , Quartzo , Areia , Cátions , Ciprofloxacina , Concentração Osmolar
11.
J Chromatogr A ; 1721: 464848, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38569299

RESUMO

The largest peak capacity (n) that LC analysis can generate in isocratic or gradient elution analysis of a given sample in a given time at a given pressure is proportional to the quality factor (qmax) of its column structure. In this study, the multi-channel structures with open pseudo-planar channels (OPPC) and open circular channels (OCC) where compared with PC2 - a typical core-shell column packed with 2 µm particles. These columns have qmax of 1.27, 1.17 and 0.41, respectively. The former two qmax are the highest among all known column structures - about 3 times higher than qmax of PC2. This means that the OPPC and OCC can generate about 3 times higher n compared to what a PC2 can in the same analysis time (tanal) at the same pressure, or they require about 81 times shorter tanal (81 is the 4th power of 3) to generate the same n as a PC2 can at the same pressure. However, while PC2 is a commercially available column, there are substantial challenges in manufacturing the OPPC and OCC that can compete with PC2 in practical applications. In order to be competitive with PC2, the OPPC and OCC should have sub-1µm characteristic dimensions (e.g., the inter-pillar distance, g, in OPPC-based pillar array columns, internal diameters of OCC). Thus, in order to compete with PC2 in one scenario, an OPPC requires g ≤ 0.14 µm. Additionally, to be competitive with PC2, OPPC and OCC should be able to sustain the same high pressure. Highlighting the challenges of their design and manufacturing might help to develop the manufacturable columns substantially superior to the packed ones.


Assuntos
Tamanho da Partícula , Cromatografia Líquida de Alta Pressão/métodos , Porosidade
12.
Biofabrication ; 16(3)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38569492

RESUMO

Tissue engineering has emerged as an advanced strategy to regenerate various tissues using different raw materials, and thus it is desired to develop more approaches to fabricate tissue engineering scaffolds to fit specific yet very useful raw materials such as biodegradable aliphatic polyester like poly (lactide-co-glycolide) (PLGA). Herein, a technique of 'wet 3D printing' was developed based on a pneumatic extrusion three-dimensional (3D) printer after we introduced a solidification bath into a 3D printing system to fabricate porous scaffolds. The room-temperature deposition modeling of polymeric solutions enabled by our wet 3D printing method is particularly meaningful for aliphatic polyester, which otherwise degrades at high temperature in classic fuse deposition modeling. As demonstration, we fabricated a bilayered porous scaffold consisted of PLGA and its mixture with hydroxyapatite for regeneration of articular cartilage and subchondral bone. Long-termin vitroandin vivodegradation tests of the scaffolds were carried out up to 36 weeks, which support the three-stage degradation process of the polyester porous scaffold and suggest faster degradationin vivothanin vitro. Animal experiments in a rabbit model of articular cartilage injury were conducted. The efficacy of the scaffolds in cartilage regeneration was verified through histological analysis, micro-computed tomography (CT) and biomechanical tests, and the influence of scaffold structures (bilayerversussingle layer) onin vivotissue regeneration was examined. This study has illustrated that the wet 3D printing is an alternative approach to biofabricate tissue engineering porous scaffolds based on biodegradable polymers.


Assuntos
Cartilagem Articular , Animais , Coelhos , Porosidade , Microtomografia por Raio-X , Temperatura , Tecidos Suporte/química , Engenharia Tecidual/métodos , Polímeros , Poliésteres , Impressão Tridimensional
13.
J Chromatogr A ; 1721: 464854, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38579528

RESUMO

Developing adsorbents with high performance and long service life for effective extracting the trace organochlorine pesticides (OCPs) from real water is attracting numerous attentions. Herein, a self-standing covalent organic framework (COF-TpPa) membrane with fiber morphology was successfully synthesized by using electrospun nanofiber membranes as template and employed as solid-phase microextraction (SPME) coating for ultra-high sensitivity extraction and analysis of trace OCPs in water. The as-synthesized COF-TpPa membrane exhibited a high specific surface area (800.83 m2 g-1), stable nanofibrous structure, and excellent chemical and thermal stability. Based on the COF-TpPa membrane, a new SPME analytical method in conjunction with gas chromatography-mass spectrometry (GC-MS) was established. This proposed method possessed favorable linearity in concentration of 0.05-2000 ng L-1, high sensitivity with enrichment factors ranging from 2175 to 5846, low limits of detection (0.001-0.150 ng L-1), satisfactory precision (RSD < 10 %), and excellent repeatability (>150 cycles), which was better than most of the reported works. Additionally, the density functional theory (DFT) calculations and XPS results demonstrated that the outstanding enrichment performance of the COF-TpPa membrane was owing to synergistic effect of π-π stacking effects, high specific surface area and hydrogen bonding. This work will expect to extend the applications of COF membrane to captures trace organic pollutants in complex environmental water, as well as offer a multiscale interpretation for the design of effective adsorbents.


Assuntos
Hidrocarbonetos Clorados , Estruturas Metalorgânicas , Nanofibras , Praguicidas , Poluentes Químicos da Água , Água , Porosidade , Poluentes Químicos da Água/análise , Microextração em Fase Sólida/métodos , Praguicidas/análise , Hidrocarbonetos Clorados/análise
14.
PLoS One ; 19(4): e0297677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635561

RESUMO

A nitrogen-phosphorus dual-doped porous spore carbon (NP-PSC) positive electrode matrix was prepared using native auricularia auricula as solid medium based on the principle of biomass rot. Yeast was introduce and cultured by the auricularia auricula solid medium. The freeze-drying and carbonization activation processes made the materials present a three-dimensional porous spore carbon aerogel properties. Yeast fermentation transformed auricularia auricula from blocky structure to porous structure and introduced nitrogen-phosphorus dual-doping. The physical and chemical properties of the prepared materials were characterized in detail. Electrochemical performance of NP-PSC in Li-S batteries was systematically investigated. Porous structure and heteroatom-doping improved the electrochemical performance, which is much superior to conventional activated carbon materials.


Assuntos
Auricularia , Lítio , Saccharomyces cerevisiae , Porosidade , Íons , Nitrogênio , Fósforo
15.
Anal Chem ; 96(15): 5746-5751, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38556995

RESUMO

Microflow porous graphitized carbon liquid chromatography (PGC-LC) combined with negative mode ionization mass spectrometry (MS) provides high resolution separation and identification of reduced native N-glycan structural isomers. However, insufficient spray quality and low ionization efficiency of N-glycans present challenges for negative mode electrospray. Here, we evaluated the performance of a recently developed multinozzle electrospray source (MnESI) and accompanying M3 emitter for microflow PGC-LC-MS analysis of N-glycans in negative mode. In comparison to a standard electrospray ionization source, the MnESI with an M3 emitter improves signal intensity, identification, quantification, and resolution of structural isomers to accommodate low-input samples.


Assuntos
Carbono , 60705 , Carbono/química , Espectrometria de Massas em Tandem/métodos , Porosidade , Polissacarídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos
16.
ACS Appl Mater Interfaces ; 16(15): 18522-18533, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564436

RESUMO

The creation of large, volumetric tissue-engineered constructs has long been hindered due to the lack of effective vascularization strategies. Recently, 3D printing has emerged as a viable approach to creating vascular structures; however, its application is limited. Here, we present a simple and controllable technique to produce porous, free-standing, perfusable tubular networks from sacrificial templates of polyelectrolyte complex and coatings of salt-containing citrate-based elastomer poly(1,8-octanediol-co-citrate) (POC). As demonstrated, fully perfusable and interconnected POC tubular networks with channel diameters ranging from 100 to 400 µm were created. Incorporating NaCl particulates into the POC coating enabled the formation of micropores (∼19 µm in diameter) in the tubular wall upon particulate leaching to increase the cross-wall fluid transport. Casting and cross-linking gelatin methacrylate (GelMA) suspended with human osteoblasts over the free-standing porous POC tubular networks led to the fabrication of 3D cell-encapsulated constructs. Compared to the constructs without POC tubular networks, those with either solid or porous wall tubular networks exhibited a significant increase in cell viability and proliferation along with healthy cell morphology, particularly those with porous networks. Taken together, the sacrificial template-assisted approach is effective to fabricate tubular networks with controllable channel diameter and patency, which can be easily incorporated into cell-encapsulated hydrogels or used as tissue-engineering scaffolds to improve cell viability.


Assuntos
Hidrogéis , Tecidos Suporte , Humanos , Hidrogéis/química , Sobrevivência Celular , Porosidade , Tecidos Suporte/química , Engenharia Tecidual/métodos , Impressão Tridimensional , Gelatina/química
17.
PLoS One ; 19(4): e0300326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626003

RESUMO

This study aimed to reduce the risk of graft occlusion by evaluating the two-phase flow of blood and LDL nanoparticles in coronary artery grafts. The study considered blood as an incompressible Newtonian fluid, with the addition of LDL nanoparticles, and the artery wall as a porous medium. Two scenarios were compared, with constant inlet velocity (CIV) and other with pulsatile inlet velocity (PIV), with LDL nanoparticles experiencing drag, wall-induced lift, and induced Saffman lift forces, or drag force only. The study also evaluated the concentration polarization of LDLs (CP of LDLs) near the walls, by considering the artery wall with and without permeation. To model LDL nanoparticles, the study randomly injected 100, 500, and 1000 nanoparticles in three release states at each time step, using different geometries. Numerical simulations were performed using COMSOL software, and the results were presented as relative collision of nanoparticles to the walls in tables, diagrams, and shear stress contours. The study found that a graft implantation angle of 15° had the most desirable conditions compared to larger angles, in terms of nanoparticle collision with surfaces and occlusion. The nanoparticle release modes behaved similarly in terms of collision with the surfaces. A difference was observed between CIV and PIV. Saffman lift and wall-induced lift forces having no effect, possibly due to the assumption of a porous artery wall and perpendicular outlet flow. In case of permeable artery walls, relative collision of particles with the graft wall was larger, suggesting the effect of CP of LDLs.


Assuntos
Baías , Vasos Coronários , Simulação por Computador , Porosidade , Modelos Cardiovasculares , Velocidade do Fluxo Sanguíneo , Estresse Mecânico
18.
Medicine (Baltimore) ; 103(14): e37697, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579049

RESUMO

BACKGROUND: Total knee arthroplasty involves the use of cemented tibial components for fixation. In recent years, cementless porous tantalum tibial components have been increasingly utilized. The aim of this meta-analysis was to compare the efficacy of cementless porous tantalum tibial components with traditional cemented tibial components in terms of postoperative outcomes following total knee arthroplasty. METHODS: Relevant literature was retrieved from Cochrane Library, PubMed, Embase, and Web of Science using the search terms "(trabecular metal OR Porous tantalum)" AND "knee" up to July 2023. The weighted mean difference with a 95% confidence interval was used as the effect size measure to evaluate the functional recovery of the knee joint, radiological analysis, complications, and implant revisions between cementless porous tantalum tibial components and traditional cemented tibial components after total knee arthroplasty. Review Manager 5.3 was utilized to conduct a comparative analysis of all included studies. RESULTS: Nine studies with a total of 1117 patients were included in this meta-analysis, consisting of 447 patients in the porous tantalum group and 670 patients in the cemented group. Radiological analysis demonstrated that the porous tantalum group had better outcomes than the cemented group (P < .05). The combined results for the 5-year and 10-year follow-ups, range of motion, Western Ontario and McMaster University Osteoarthritis Index, complications, and implant revisions showed no significant differences between the porous tantalum and cemented groups. CONCLUSION: The results of the 5-year and 10-year follow-ups indicate that the use of cementless porous tantalum tibial components is comparable to traditional cemented tibial components, with no significant advantages observed. However, at the 5-year follow-up, the porous tantalum group demonstrated a good bone density in the proximal tibia. Future studies with a larger sample size, long-term clinical follow-up, and radiological results are needed to verify the differences between the 2 implants.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Humanos , Artroplastia do Joelho/métodos , Tantálio , Tíbia/cirurgia , Porosidade , Resultado do Tratamento , Articulação do Joelho/cirurgia , Desenho de Prótese , Cimentos Ósseos , Osteoartrite do Joelho/cirurgia
20.
Int J Nanomedicine ; 19: 2199-2225, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38465205

RESUMO

Solid oral dosage forms are mostly preferred in pharmaceutical formulation development due to patient convenience, ease of product handling, high throughput, low manufacturing costs, with good physical and chemical stability. However, 70% of drug candidates have poor water solubility leading to compromised bioavailability. This phenomenon occurs because drug molecules are often absorbed after dissolving in gastrointestinal fluid. To address this limitation, delivery systems designed to improve the pharmacokinetics of drug molecules are needed to allow controlled release and target-specific delivery. Among various strategies, amorphous formulations show significantly high potential, particularly for molecules with solubility-limited dissolution rates. The ease of drug molecules to amorphized is known as their glass-forming ability (GFA). Specifically, drug molecules categorized into class III based on the Taylor classification have a low recrystallization tendency and high GFA after cooling, with substantial "glass stability" when heated. In the last decades, the application of mesoporous silica nanoparticles (MSNs) as drug delivery systems (DDS) has gained significant attention in various investigations and the pharmaceutical industry. This is attributed to the unique physicochemical properties of MSNs, including high loading capacity, recrystallization inhibition, excellent biocompatibility, and easy functionalization. Therefore, this study aimed to discuss the current state of good glass former drug loaded mesoporous silica and shows its impact on the pharmaceutical properties including dissolution and physical stability, along with in vivo study. The results show the importance of determining whether mesoporous structures are needed in amorphous formulations to improve the pharmaceutical properties of drug with a favorable GFA.


Assuntos
Nanopartículas , Dióxido de Silício , Humanos , Preparações Farmacêuticas/química , Dióxido de Silício/química , Sistemas de Liberação de Medicamentos , Solubilidade , Liberação Controlada de Fármacos , Nanopartículas/química , Porosidade , Portadores de Fármacos/química
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