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A smart, tumor-trigged, controlled drug release using inorganic "caps" with CO3 (2-) functional groups in electrospun fibers is presented for inhibiting cancer relapse. When the drug-loaded intelligent electrospun fibers encounter pathological acidic environments, the inorganic gates react with the acids and produce CO2 gas, which enables water penetration into the core of the fibers to induce rapid drug release.
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Carbonato de Calcio/química , Liberación de Fármacos , Neoplasias/metabolismo , Neoplasias/patología , Preparaciones de Acción Retardada , Doxorrubicina/farmacología , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/química , Poliésteres , Polímeros/química , RecurrenciaRESUMEN
Skin injury in adult mammals brings about a series of events and inflammation in the wounded area is initiated first and provides lots of inflammatory factors, which is critical for the final scar formation. While the postinjured skin of fetus and nude mice heals scarlessly owing to the absence of inflammation or immunodeficient, we designed a feasible acid-responsive ibuprofen-loaded poly(L-lactide) (PLLA) fibrous scaffolds via doping sodium bicarbonate to prevent excessive inflammation and achieve scarless healing finally. The morphological results of in vivo experiments revealed that animals treated with acid-responsive ibuprofen-loaded PLLA fibrous scaffolds exhibited alleviative inflammation, accelerated healing process, and regulated collagen deposition via interference in the collagen distribution, the α-smooth muscle actin (α-SMA), and the basic fibroblast growth factor (bFGF) expression. The lower ratios of collagen I/collagen III and TGF-ß1/TGF-ß3 and higher ratio of matrix metalloproteinase-1 (MMP-1)/tissue inhibitor of metalloproteinase-1 (TIMP-1) in acid-responsive ibuprofen-loaded PLLA fibrous scaffolds group were confirmed by real-time qPCR as well. These results suggest that inhibiting the excessive inflammation will result in regular collagen distribution and appropriate ratio between the factors, which promote or suppress the scar formation, then decrease the scar area, and finally achieve the scarless healing.
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Andamios del Tejido/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Ibuprofeno/administración & dosificación , Ibuprofeno/uso terapéutico , Inflamación/tratamiento farmacológico , Ácido Láctico/química , Masculino , Poliésteres , Polímeros/química , Ratas , Ratas Sprague-Dawley , Piel/efectos de los fármacos , Piel/inmunologíaRESUMEN
Enzymatic mineralization is an advanced mineralization method that is often used to enhance the stiffness and strength of hydrogels, but often accompanied by brittle behavior. Moreover, the hydrogel systems with dense networks currently used for enzymatic mineralization are not ideal materials for bone repair applications. To address these issues, two usual bone repair hydrogels, poly(vinyl alcohol) (PVA) and sodium alginate (SA), were selected to form a double-network structure through repeated freeze-thawing and ionic cross-linking, followed by enzyme mineralization. The results demonstrated that both enzymatic mineralization and double-network structure improved the mechanical and biological properties and even exhibited synergistic effects. The mineralized PVASA hydrogels exhibited superior comprehensive mechanical properties, with a Young's modulus of 1.03 MPa, a storage modulus of 103 kPa, and an equilibrium swelling ratio of 132%. In particular, the PVASA hydrogel did not suffer toughness loss after mineralization, with a high toughness value of 1.86 MJ/m3. The prepared hydrogels also exhibited superior biocompatibility with a cell spreading area about 13 times that of mineralized PVA. It also effectively promoted cellular osteogenic differentiation in vitro and further promoted the formation of new bone in the femur defect region in vivo. Overall, the enzyme-mineralized PVASA hydrogel demonstrated combined strength and toughness and great potential for bone tissue engineering applications.
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Osteogénesis , Ingeniería de Tejidos , Hidrogeles/farmacología , Hidrogeles/química , Huesos , Alcohol Polivinílico/químicaRESUMEN
Helicobacter pylori (HP), a common microanaerobic bacteria that lives in the human mouth and stomach, is reported to infect ≈50% of the global population. The current diagnostic methods for HP are either invasive, time-consuming, or harmful. Therefore, a noninvasive and label-free HP diagnostic method needs to be developed urgently. Herein, reduced graphene oxide (rGO) is composited with different metal-based materials to construct a graphene-based electronic nose (e-nose), which exhibits excellent sensitivity and cross-reactive response to several gases in exhaled breath (EB). Principal component analysis (PCA) shows that four typical types of gases in EB can be well discriminated. Additionally, the potential of the e-nose in label-free detection of HP infection is demonstrated through the measurement and analysis of EB samples. Furthermore, a prototype of an e-nose device is designed and constructed for automatic EB detection and HP diagnosis. The accuracy of the prototype machine integrated with the graphene-based e-nose can reach 92% and 91% in the training and validation sets, respectively. These results demonstrate that the highly sensitive graphene-based e-nose has great potential for the label-free diagnosis of HP and may become a novel tool for non-invasive disease screening and diagnosis.
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Stem cell tissue engineering is a potential treatment for osteoarthritis. However, the number of stem cells that can be delivered, loss of stem cells during injection, and migration ability of stem cells limit applications of traditional stem cell tissue engineering. Herein, kartogenin (KGN)-loaded poly(lactic-co-glycolic acid) (PLGA) porous microspheres is first engineered via emulsification, and then anchored with chitosan through the amidation reaction to develop a new porous microsphere (PLGA-CS@KGN) as a stem cell expansion vector. Following 3D co-culture of the PLGA-CS@KGN carrier with mesenchymal stem cells (MSCs), the delivery system is injected into the capsule cavity in situ. In vivo and in vitro experiments show that PLGA-CS microspheres have a high cell-carrying capacity up to 1 × 104 mm-3 and provide effective protection of MSCs to promote their controlled release in the osteoarthritis microenvironment. Simultaneously, KGN loaded inside the microspheres effectively cooperated with PLGA-CS to induce MSCs to differentiate into chondrocytes. Overall, these findings indicate that PLGA-CS@KGN microspheres held high cell-loading ability, adapt to the migration and expansion of cells, and promote MSCs to express markers associated with cartilage repair. Thus, PLGA-CS@KGN can be used as a potential stem cell carrier for enhancing stem cell therapy in osteoarthritis treatment.
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Cartílago Articular , Osteoartritis , Humanos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Microesferas , Ácido Poliglicólico , Ácido Láctico , Porosidad , Conservación de los Recursos Naturales , Regeneración , Células Madre , Osteoartritis/terapiaRESUMEN
Colorectal cancer (CRC) is one of the most prevalent and deadly malignancies that can be influenced by Fusobacterium nucleatum (Fn), a bacterium that promotes tumor development and chemoresistance, resulting in limited therapeutic efficacy. Traditional antibiotics cannot effectively eliminate Fn at tumor site due to issues like biofilm formation, while chemotherapy alone fails to suppress tumor progression. Therefore, the development of new methods to eliminate Fn and promote antitumor efficacy is of great significance for improving the outcome of CRC treatment. Herein, we developed a nanodrug (OPPL) that integrates oleic acid-modified superparamagnetic iron oxide nanoparticles (O-SPIONs) and an amphiphilic polymer (PPL) to deliver the platinum prodrug and antimicrobial lauric acid (LA) for enhancing the treatment of CRC. We demonstrated that OPPL can synergistically enhance antibacterial and biofilm disruption activities against Fn along with the antimicrobial LA by producing reactive oxygen species (ROS) through its peroxidase-like activity. Furthermore, the OPPL nanodrug can increase intracellular ROS, promote lipid peroxides and deplete glutathione, leading to ferroptosis. By combining chemotherapy and induced ferroptosis, the OPPL nanodrug exhibited high cytotoxicity against CRC cells. In vivo studies showed that the OPPL nanodrug could enhance tumor accumulation, enable magnetic resonance imaging, suppresse tumor growth, and inhibit growth of intratumor Fn. These results suggest that OPPL is an effective and promising candidate for the treatment of Fn-infected CRC. STATEMENT OF SIGNIFICANCE: The enrichment of Fusobacterium nucleatum (Fn) in colorectal cancer is reported to exacerbate tumor malignancy and is particularly responsible for chemoresistance. To this respect, we strategically elaborated multifaceted therapeutics, namely OPPL nanodrug, combining oleic acid-modified superparamagnetic iron oxide nanoparticles (O-SPIONs) with a polymer containing a platinum prodrug and antimicrobial lauric acid. The O-SPION components exert distinctive peroxidase-like activity, capable of stimulating Fenton reactions selectively in the tumor microenvironment, consequently accounting for the progressive production of reactive oxygen species. Hence, O-SPIONs have been demonstrated to not only supplement the antimicrobial activities of lauric acid in overcoming Fn-induced chemoresistance but also stimulate potent tumor ferroptosis. Our proposed dual antimicrobial and chemotherapeutic nanodrug provides an appreciable strategy for managing challenging Fn-infected colorectal cancer.
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Antiinfecciosos , Neoplasias Colorrectales , Profármacos , Humanos , Especies Reactivas de Oxígeno , Ácido Oléico , Platino (Metal) , Fusobacterium nucleatum , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Polímeros , Nanopartículas Magnéticas de Óxido de Hierro , Antibacterianos/farmacología , Peroxidasas , Línea Celular Tumoral , Microambiente TumoralRESUMEN
A CoAl-layered double hydroxide (LDH)@poly(3,4-ethylenedioxythiophene) (PEDOT) core/shell nanoplatelet array (NPA) is grown on a flexible Ni foil substrate as a high-performance pseudocapacitor. The LDH@PEDOT core/shell NPA shows a maximum specific capacitance of 649 F/g (based on the total mass) by cyclic voltammetry (scan rate: 2 mV/s) and 672 F/g by galvanostatic discharge (current density: 1 A/g). Furthermore, the hybrid NPA electrode also exhibits excellent rate capability with a specific energy of 39.4 Wh/kg at a current density of 40 A/g, as well as good long-term cycling stability (92.5% of its original capacitance is retained after 5000 cycles). These performances are superior to those of conventional supercapacitors and LDH NPA without the PEDOT coating. The largely enhanced pseudocapacitor behavior of the LDH@PEDOT NPA electrode is related to the synergistic effect of its individual components: the LDH nanoplatelet core provides abundant energy-storage capacity, while the highly conductive PEDOT shell and porous architecture facilitate the electron/mass transport in the redox reaction.
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Compuestos Bicíclicos Heterocíclicos con Puentes/química , Nanopartículas/química , Nanotecnología/métodos , Polímeros/química , Aluminio/química , Cobalto/química , Análisis Costo-Beneficio , Difusión , Electroquímica/métodos , Electrodos , Electrones , Hidróxidos/química , Microscopía Electrónica de Rastreo/métodos , Modelos Químicos , Modelos Estadísticos , Níquel/química , Oxidación-Reducción , Óxidos/químicaRESUMEN
The hierarchical architecture and complex biologic functions of native sheath make its biomimetic substitute a daunting challenge. In this study, a biomimetic bilayer sheath membrane consisting of hyaluronic acid-loaded poly(ε-caprolactone) (HA/PCL) fibrous membrane as the inner layer and PCL fibrous membrane as the outer layer was fabricated by a combination of sequential and microgel electrospinning technologies. This material was characterized by mechanical testing and analysis of morphology, surface wettability, and drug release. Results of an in vitro drug release study showed sustained release. The outer layer had fewer cells proliferating on its surface compared to tissue culture plates or the inner layer. In a chicken model, peritendinous adhesions were reduced and tendon gliding were improved by the application of this sheath membrane. Taken together, our results demonstrate that such a biomimetic bilayer sheath can release HA sustainably as well as promoting tendon gliding and preventing adhesion.
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Materiales Biomiméticos/uso terapéutico , Ácido Hialurónico/administración & dosificación , Ácido Hialurónico/química , Poliésteres/química , Traumatismos de los Tendones/cirugía , Tendones/patología , Tendones/cirugía , Adherencias Tisulares/terapia , Animales , Biomimética , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Células Cultivadas , Pollos , Geles/síntesis química , Geles/química , Ratones , Ratones Endogámicos C3H , Adherencias Tisulares/prevención & controlRESUMEN
Cellulose with distinct colloidal states exhibited different adsorption capability for ions and whether the intake of cellulose would bring positive or negative influence on the mineral bioavailability is inconclusive. This work investigated the binding behavior of carboxymethyl cellulose (CMC), TEMPO-oxidized nanofibrillated/nanocrystalline cellulose (TOCNF/TOCNC), and microcrystalline cellulose (MCC) with Ca2+and Zn2+ and compared their effects on mineral bioavailability in vitro and in vivo. The results suggested that CMC displayed a higher adsorption capability (36.6 mg g-1 for Ca2+ and 66.2 mg g-1 for Zn2+) than the other types of cellulose because of the strong interaction between carboxyl groups of cellulose and the ions. Although the cellulose derivatives had adverse effects on ion adsorption in vitro, the fermentability endowed by TOCNF/TOCNC counterbalanced the negative impacts in vivo. The findings suggested that the colloidal states of cellulose affected the bioavailability of minerals and could provide useful guidance for applications of specific cellulose.
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Carboximetilcelulosa de Sodio , Celulosa , Adsorción , Disponibilidad Biológica , Celulosa/química , Iones , Minerales , ZincRESUMEN
Sjögrens syndrome (SS) is caused by autoantibodies that attack proprioceptive salivary and lacrimal gland tissues. Damage to the glands leads to dry mouth and eyes and affects multiple systems and organs. In severe cases, SS is life-threatening because it can lead to interstitial lung disease, renal insufficiency, and lymphoma. Histological examination of the labial minor salivary glands of patients with SS reveals focal lymphocyte aggregation of T and B cells. More studies have been conducted on the role of B cells in the pathogenesis of SS, whereas the role of T cells has only recently attracted the attention of researchers. This review focusses on the role of various populations of T cells in the pathogenesis of SS and the progress made in research to therapeutically targeting T cells for the treatment of patients with SS.
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Aparato Lagrimal , Síndrome de Sjögren , Humanos , Síndrome de Sjögren/etiología , Síndrome de Sjögren/terapia , Síndrome de Sjögren/diagnóstico , Linfocitos T/patología , Glándulas Salivales Menores/patología , Aparato Lagrimal/patología , AutoanticuerposRESUMEN
Background: Saliva secretion and oral microbiota change in rhythm with our biological clock. Dysbiosis of the oral microbiome and alcohol consumption have a two-way interactive impact, but little is known about whether the oral microbiome undergoes diurnal changes in composition and function during the daytime in patients with alcohol dependence (AD). Methods: The impact of alcohol consumption on the diurnal salivary microbiome was examined in a case-control study of 32 AD patients and 21 healthy control (HC) subjects. We tested the changes in microbial composition and individual taxon abundance by 16S rRNA gene sequencing. Results: The present study is the first report showing that alcohol consumption enhanced the richness of the salivary microbiome and lowered the evenness. The composition of the oral microbiota changed significantly in alcohol-dependent patients. Additionally, certain genera were enriched in the AD group, including Actinomyces, Leptotrichia, Sphaerochaeta and Cyanobacteria, all of which have pathogenic effects on the host. There is a correlation between liver enzymes and oral microbiota. KEGG function analysis also showed obvious alterations during the daytime. Conclusion: Alcohol drinking influences diurnal changes in the oral microbiota, leading to flora disturbance and related functional impairment. In particular, the diurnal changes of the oral microbiota may open avenues for potential interventions that can relieve the detrimental consequences of AD.
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Alcoholismo , Microbiota , Humanos , Saliva/microbiología , ARN Ribosómico 16S/genética , Estudios de Casos y Controles , Disbiosis/microbiologíaRESUMEN
The ordered ultrathin films (UTFs) based on CoFe-LDH (layered double hydroxide) nanoplatelets and manganese porphyrin (Mn-TPPS) have been fabricated on ITO substrates via a magnetic-field-assisted (MFA) layer-by-layer (LBL) method and were demonstrated as an electrochemical sensor for glucose. The XRD pattern for the film indicates a long-range stacking order in the normal direction of the substrate. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images of the MFA LDH/Mn-TPPS UTFs reveal a continuous and uniform surface morphology. Cyclic voltammetry, impedance spectroscopy, and chronoamperometry were used to evaluate the electrochemical performance of the film, and the results show that the MFA-0.5 (0.5 T magnetic field) CoFe-LDH/Mn-TPPS-modified electrode displays the strongest redox current peaks and fastest electron transfer process compared with those of MFA-0 (without magnetic-field) and MFA-0.15 (0.15 T magnetic field). Furthermore, the MFA-0.5 CoFe-LDH/Mn-TPPS exhibits remarkable electrocatalytic activity toward the oxidation of glucose with a linear response range (0.1-15 mM; R(2) = 0.999), low detection limit (0.79 µM) and high sensitivity (66.3 µA mM(-1) cm(-2)). In addition, the glucose sensor prepared by the MFA LBL method also shows good selectivity and reproducibility as well as resistance to poisoning in a chloride ion solution. Therefore, the novel strategy in this work creates new opportunities for the fabrication of nonenzyme sensors with prospective applications in practical detection.
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Glucosa/análisis , Hidróxidos/química , Magnetismo , Membranas Artificiales , Metaloporfirinas/química , Electrodos , Tamaño de la Partícula , Propiedades de SuperficieRESUMEN
Three typical waste furniture boards, including fiberboard, chipboard, and blockboard, were pretreated with conventional hydrothermal method. The responses of chemical composition, physicochemical morphology, and performances of enzymatic hydrolysis were evaluated. Results indicated the almost complete hemicellulose removal at higher pretreatment temperatures, the enhanced crystallinity index, and disordered morphology of the pretreated substrates indicated that the hydrothermal pretreatment deconstructed these boards well. However, the very low enzymatic hydrolysis (< 8% after 72 h) of the pretreated substrates showed the poor biological conversion. Three hypotheses for the weakened enzymatic hydrolysis were investigated, and results indicated that the residual adhesives and their degraded fractions were mainly responsible for poor hydrolysis. When NaOH post-pretreatment was attempted, cellulose-glucose conversion of the hydrothermally pretreated fiberboard, chipboard and blockboard can be improved to 28.5%, 24.1%, and 37.5%. Herein, the process of NaOH hydrothermal pretreatment was integrated, by which the hydrolysis of pretreated fiberboard, chipboard and blockboard was greatly promoted to 47.1%, 37.3%, and 53.8%, suggesting a possible way to pretreat these unconventional recalcitrant biomasses.
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Enzimas/metabolismo , Lignina/química , Temperatura , Residuos , Biomasa , Glucosa/química , Hidrólisis , Cinética , Hidróxido de Sodio/químicaRESUMEN
Implantable tissue engineering scaffolds with temporally programmable multi-drug release are recognized as promising tools to improve therapeutic effects. A good example would be one that exhibits initial anti-inflammatory and long-term anti-tumor activities after tumor resection. In this study, a new strategy for self-coated interfacial layer on drug-loaded mesoporous silica nanoparticles (MSNs) based on mussel-mimetic catecholamine polymer (polydopamine, PDA) layer was developed between inorganic and organic matrix for controlling drug release. When the interface PDA coated MSNs were encapsulated in electrospun poly(L-lactide) (PLLA) fibers, the release rates of drugs located inside/outside the interfacial layer could be finely controlled, with short-term release of anti-inflammation ibuprofen (IBU) for 30 days in absence of interfacial interactions and sustained long-term release of doxorubicin (DOX) for 90 days in presence of interfacial interactions to inhibit potential tumor recurrence. The DOX@MSN-PDA/IBU/PLLA hybrid fibrous scaffolds were further found to inhibit proliferation of inflammatory macrophages and cancerous HeLa cells, while supporting the normal stromal fibroblast adhesion and proliferation at different release stages. These results have suggested that the interfacial obstruction layer at the organic/inorganic phase was able to control the release of drugs inside (slow)/outside (rapid) the interfacial layer in a programmable manner. We believe such interface polymer strategy will find applications in where temporally controlled multi-drug delivery is needed.
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Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Ibuprofeno/administración & dosificación , Nanopartículas/química , Dióxido de Silicio/química , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacocinética , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacocinética , Células HeLa , Humanos , Ibuprofeno/química , Ibuprofeno/farmacocinética , Indoles/química , Macrófagos/citología , Macrófagos/efectos de los fármacos , Ratones , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Células 3T3 NIH , Nanopartículas/ultraestructura , Poliésteres/química , Polímeros/química , PorosidadRESUMEN
Clinically, rotator cuff tear (RCT) is among the most common shoulder pathologies. Despite significant advances in surgical techniques, the re-tear rate after rotator cuff (RC) repair remains high. Insufficient healing capacity is likely the main factor for reconstruction failure. This study reports on a basic fibroblast growth factor (bFGF)-loaded electrospun poly(lactide-co-glycolide) (PLGA) fibrous membrane for repairing RCT. Implantable biodegradable bFGF-PLGA fibrous membranes were successfully fabricated using emulsion electrospinning technology and then characterized and evaluated with in vitro and in vivo cell proliferation assays and repairs of rat chronic RCTs. Emulsion electrospinning fabricated ultrafine fibers with a core-sheath structure which secured the bioactivity of bFGF in a sustained manner for 3 weeks. Histological observations showed that electrospun fibrous membranes have excellent biocompatibility and biodegradability. At 2, 4, and 8 weeks after in vivo RCT repair surgery, electrospun fibrous membranes significantly increased the area of glycosaminoglycan staining at the tendon-bone interface compared with the control group, and bFGF-PLGA significantly improved collagen organization, as measured by birefringence under polarized light at the healing enthesis compared with the control and PLGA groups. Biomechanical testing showed that the electrospun fibrous membrane groups had a greater ultimate load-to-failure and stiffness than the control group at 4 and 8 weeks. The bFGF-PLGA membranes had the highest ultimate load-to-failure, stiffness, and stress of the healing enthesis, and their superiority compared to PLGA alone was significant. These results demonstrated that electrospun fibrous membranes aid in cell attachment and proliferation, as well as accelerating tendon-bone remodeling, and bFGF-loaded PLGA fibrous membranes have a more pronounced effect on tendon-bone healing. Therefore, augmentation using bFGF-PLGA electrospun fibrous membranes is a promising treatment for RCT.
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Implantes de Medicamentos/administración & dosificación , Factor 2 de Crecimiento de Fibroblastos/administración & dosificación , Membranas Artificiales , Lesiones del Manguito de los Rotadores , Traumatismos de los Tendones/terapia , Ingeniería de Tejidos/instrumentación , Andamios del Tejido , Animales , Galvanoplastia/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Regeneración Tisular Dirigida/instrumentación , Regeneración Tisular Dirigida/métodos , Masculino , Ratas , Ratas Sprague-Dawley , Rotación , Manguito de los Rotadores/cirugía , Traumatismos de los Tendones/patología , Resultado del TratamientoRESUMEN
Vasospasm is a common post-operative complication after vascular anastomosis. Currently, the main treatment is a local injection of antispasmodic drugs. However, this method has a high rate of relapse and is subject to a large degree of individual variation, and repeated injections cause additional pain for patients. In this study, we developed highly flexible and rapidly degradable papaverine-loaded electrospun fibrous membranes to be wrapped around vascular suturing to prevent vasospasm. Poly-l-lactic acid/polyethylene glycol (PLLA/PEG) electrospun fibers containing papaverine maintained a high degree of flexibility and could withstand any folding, and are therefore suitable for wrapping vascular suturing. A rapid release of papaverine, between 2 and 7 days, was achieved by adjusting the proportions of PEG and PLLA. PLLA electrospun fibers containing 40% PEG (PLLA-40%) could control drug release and polymer degradation most effectively during the first 2 weeks post-operation. Testing using an in vivo rabbit model showed that PLLA-40% fibrous membranes produced significant antispasmodic effect without observable inflammation or hyperplasia, and the fibrous membranes were ideally biodegradable, with no impact on regional blood flow, pressure, vessel diameter or surrounding tissue hyperplasia. Therefore, papaverine-loaded electrospun fibrous membranes show the potential to greatly reduce post-operative vasospasm and maintain regular vascular morphology during antispasmodic therapy.
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Vasoespasmo Coronario/prevención & control , Membranas Artificiales , Papaverina/administración & dosificación , Animales , Microscopía Electrónica de Rastreo , Papaverina/sangre , Conejos , Ultrasonografía Doppler en ColorRESUMEN
The complications of tendon injury are frequently compromised by peritendinous adhesions and tendon sheath infection. Physical barriers for anti-adhesion may increase the incidence of postoperative infection. This study was designed to evaluate the potential of silver nanoparticles (AgNPs)-loaded poly(L-lactide) (PLLA) electrospun fibrous membranes to prevent adhesion formation and infection. Results of an in vitro drug release study showed that a burst release was followed by sustained release from electrospun fibrous membranes with a high initial silver content. Fewer fibroblasts adhered to and proliferated on the AgNP-loaded PLLA electrospun fibrous membranes compared with pure PLLA electrospun fibrous membrane. In the antibacterial test, the AgNP-loaded PLLA electrospun fibrous membranes can prevent the adhesion of Gram-positive Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa. Taken together, these results demonstrate that AgNP-loaded PLLA electrospun fibrous membranes have the convenient practical medical potential of reduction of infection and adhesion formation after tendon injury.
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Antibacterianos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Membranas Artificiales , Nanopartículas del Metal/química , Nanofibras/química , Poliésteres/farmacología , Plata/farmacología , Animales , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Iones , Ratones , Pruebas de Sensibilidad Microbiana , Microscopía Confocal , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanofibras/ultraestructura , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/ultraestructura , Staphylococcus/efectos de los fármacos , Staphylococcus/ultraestructuraRESUMEN
Acid-responsive electrospun fibers are fabricated by introducing sodium bicarbonate into PLLA fibers using an emulsion method. This novel electrospun fibrous scaffold exhibits a rapid acid-responsive controlled drug release (early stage) and stable three-dimensional (3D) structure as a tissue engineering scaffold (late stage) for cell growth.
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Portadores de Fármacos/química , Polímeros/uso terapéutico , Ingeniería de Tejidos , Andamios del Tejido/química , Materiales Biocompatibles , Proliferación Celular/efectos de los fármacos , Portadores de Fármacos/uso terapéutico , Humanos , Ácido Láctico/farmacología , Polímeros/química , Bicarbonato de Sodio/químicaRESUMEN
A novel inorganic-organic composite ultrathin film was fabricated by layer-by-layer assembly of naphthol green B (NGB) and layered double hydroxides (LDHs) nanoplatelets, which shows remarkable electrocatalytic behavior for oxidation of ascorbic acid. LDHs nanoplatelets were prepared using a method involving separate nucleation and aging steps (particle size: 25±5 nm; aspect ratio: 2-4) and used as building blocks for alternate deposition with NGB on indium tin oxide (ITO) substrates. UV-vis absorption spectroscopy and XRD display regular and uniform growth of the NGB/LDHs ultrathin film with extremely c-orientation of LDHs nanoplatelets (ab plane of microcrystals parallel to substrates). A continuous and uniform surface morphology was observed by SEM and AFM image. The film modified electrode displays a couple of well-defined reversible redox peaks attributed to Fe(2+)/Fe(3+) in NGB (ΔE(p)=68 mV and I(a)/I(c)=1.1). Moreover, the modified electrode shows a high electrocatalytic activity towards ascorbic acid in the range 1.2-55.2 µM with a detection limit of 0.51 µM (S/N=3). The Michaelis-Menten constant was calculated to be K(M)(app)=67.5 µM.