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1.
Front Hum Neurosci ; 18: 1387471, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952644

RESUMEN

Objective: This study aimed to explore the electroencephalogram (EEG) indicators and clinical factors that may lead to poor prognosis in patients with prolonged disorder of consciousness (pDOC), and establish and verify a clinical predictive model based on these factors. Methods: This study included 134 patients suffering from prolonged disorder of consciousness enrolled in our department of neurosurgery. We collected the data of sex, age, etiology, coma recovery scales (CRS-R) score, complications, blood routine, liver function, coagulation and other laboratory tests, resting EEG data and follow-up after discharge. These patients were divided into two groups: training set (n = 107) and verification set (n = 27). These patients were divided into a training set of 107 and a validation set of 27 for this study. Univariate and multivariate regression analysis were used to determine the factors affecting the poor prognosis of pDOC and to establish nomogram model. We use the receiver operating characteristic (ROC) and calibration curves to quantitatively test the effectiveness of the training set and the verification set. In order to further verify the clinical practical value of the model, we use decision curve analysis (DCA) to evaluate the model. Result: The results from univariate and multivariate logistic regression analyses suggested that an increased frequency of occurrence microstate A, reduced CRS-R scores at the time of admission, the presence of episodes associated with paroxysmal sympathetic hyperactivity (PSH), and decreased fibrinogen levels all function as independent prognostic factors. These factors were used to construct the nomogram. The training and verification sets had areas under the curve of 0.854 and 0.920, respectively. Calibration curves and DCA demonstrated good model performance and significant clinical benefits in both sets. Conclusion: This study is based on the use of clinically available and low-cost clinical indicators combined with EEG to construct a highly applicable and accurate model for predicting the adverse prognosis of patients with prolonged disorder of consciousness. It provides an objective and reliable tool for clinicians to evaluate the prognosis of prolonged disorder of consciousness, and helps clinicians to provide personalized clinical care and decision-making for patients with prolonged disorder of consciousness and their families.

2.
Skin Res Technol ; 30(6): e13764, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38853456

RESUMEN

Injectable fillers, pivotal in aesthetic medicine, have evolved significantly with recent trends favoring biostimulators like calcium hydroxylapatite (CaHA-CMC; Radiesse, Merz Aesthetics, Raleigh, NC) and poly-l-lactic acid (PLLA; Sculptra Aesthetics, Galderma, Dallas, TX). This study aims to compare the particle morphology of these two injectables and examine its potential clinical implications. Utilizing advanced light and scanning electron microscopy techniques, the physical characteristics of CaHA-CMC and PLLA particles were analyzed, including shape, size, circularity, roundness, aspect ratio, and quantity of phagocytosable particles. The findings reveal several morphological contrasts: CaHA-CMC particles exhibited a smooth, homogenous, spherical morphology with diameters predominantly ranging between 20 and 45 µm, while PLLA particles varied considerably in shape and size, appearing as micro flakes ranging from 2 to 150 µm in major axis length. The circularity and roundness of CaHA-CMC particles were significantly higher compared to PLLA, indicating a more uniform shape. Aspect ratio analysis further underscored these differences, with CaHA-CMC particles showing a closer resemblance to circles, unlike the more oblong PLLA particles. Quantification of the phagocytosable content of both injectables revealed a higher percentage of phagocytosable particles in PLLA. These morphological distinctions may influence the tissue response to each treatment. CaHA-CMC's uniform, spherical particles may result in reduced inflammatory cell recruitment, whereas PLLA's heterogeneous particle morphology may evoke a more pronounced inflammatory response.


Asunto(s)
Rellenos Dérmicos , Durapatita , Poliésteres , Durapatita/química , Poliésteres/química , Rellenos Dérmicos/química , Rellenos Dérmicos/administración & dosificación , Humanos , Técnicas Cosméticas , Tamaño de la Partícula , Materiales Biocompatibles/química , Microscopía Electrónica de Rastreo
3.
Acta Biomater ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38908416

RESUMEN

The use of decellularized extracellular matrix products in tissue regeneration is quite alluring yet practically challenging due to the limitations of its availability, harsh processing techniques, and host rejection. Scaffolds obtained by either incorporating extracellular matrix (ECM) material or coating the surface can resolve these challenges to some extent. However, these scaffolds lack the complex 3D network formed by proteins and growth factors observed in natural ECM. This study introduces an approach utilizing 3D nanofiber scaffolds decorated with dECM to enhance cellular responses and promote tissue regeneration. Notably, the dECM can be customized according to specific cellular requirements, offering a tailored environment for enhanced therapeutic outcomes. Two types of 3D expanded scaffolds, namely radially aligned scaffolds (RAS) and laterally expanded scaffolds (LES) fabricated by the gas-foaming expansion were utilized. To demonstrate the proof-of-concept, human dermal fibroblasts (HDFs) seeded on these scaffolds for up to 8 weeks, resulted in uniform and highly aligned cells which deposited ECM on the scaffolds. These cellular components were then removed from the scaffolds through decellularization (e.g., SDS treatment and freeze-thaw cycles). The dECM-decorated 3D expanded nanofiber scaffolds can direct and support cell alignment and proliferation along the underlying fibers upon recellularization. An in vitro inflammation assay indicates that dECM-decorated LES induces a lower immune response than dECM-decorated RAS. Further, subcutaneous implantation of dECM-decorated RAS and LES shows higher cell infiltration and angiogenesis within 7 and 14 days than RAS and LES without dECM decoration. Taken together, dECM-decorated 3D expanded nanofiber scaffolds hold great potential in tissue regeneration and tissue modeling. STATEMENT OF SIGNIFICANCE: Decellularized ECM scaffolds have attained widespread attention in biomedical applications due to their intricate 3D framework of proteins and growth factors. Mimicking such a complicated architecture is a clinical challenge. In this study, we developed natural ECM-decorated 3D electrospun nanofiber scaffolds with controlled alignments to mimic human tissue. Fibroblasts were cultured on these scaffolds for 8 weeks to deposit natural ECM and decellularized by either freeze-thawing or detergent to obtain decellularized ECM scaffolds. These scaffolds were tested in both in-vitro and in-vivo conditions. They displayed higher cellular attributes with lower immune response making them a good grafting tool in tissue regeneration.

4.
Bioact Mater ; 38: 154-168, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38721595

RESUMEN

Effective therapies are urgently needed to stabilize patients with marginally compressible junctional hemorrhage long enough to get them to the hospital alive. Herein, we report injectable and rapidly expandable cryogels consisting of polyacrylamide and thrombin (AT cryogels) created by cryo-polymerization for the efficient management of lethal junctional hemorrhage in swine. The produced cryogels have small pore sizes and highly interconnected porous architecture with robust mechanical strength. The cryogels exhibit rapid shape memory properties and prove to be resilient against fatigue. These cryogels also show high water/blood absorption capacity, fast blood clotting effect, and enhanced adhesion of red blood cells and platelets in vitro. Further, in vivo, hemostatic efficacy tests in a lethal swine junctional hemorrhage model suggest that treatment with AT cryogels, especially AT-2 cryogels, achieves the least blood loss and the highest survival rate (100 %) compared to currently employed products such as XStat® and combat gauze. The high hemostatic performance of the cryogels may be attributed to highly interconnected porous architecture with small pore size and the use of thrombin as a pro-coagulant agent. Collectively, injectable and rapidly expandable thrombin-decorated polyacrylamide-based cryogels show significant promise as hemostatic material, offering effective management of marginally compressible junctional hemorrhages in prehospital settings.

5.
Ultrasonics ; 141: 107344, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38772060

RESUMEN

Ultrasonic microneedle patches, a class of ultrasound-driven transdermal drug delivery systems, are promising in addressing bacterial biofilms. This device has been proven to be more effective in treating Staphylococcus aureus biofilms than drug in free solution. However, there exists a notable gap in understanding how various excitation conditions and material parameters affect drug delivery efficiency. This study aims to fill this void by conducting an comprehensive multi-physics numerical analysis of ultrasonic microneedle patches, with the ultimate goal of enhancing drug delivery. First, we investigate the impact of various ultrasound frequencies on drug penetration depths. The findings reveal that local resonance can accelerate drug release within a shorter time window (first 1.5 h), whereas non-resonant frequencies enable more profound and prolonged diffusion. This information is crucial for medical professionals in selecting the most effective frequency for optimal drug administration. Furthermore, our investigation extends to the effects of applied voltage on temperature distribution, a critical aspect for ensuring medical safety during the application of these patches. Additionally, we examine how particles of different sizes respond to acoustic pressure and streaming fields, providing valuable insights for tailoring drug delivery strategies to specific therapeutic needs. Overall, our findings offer comprehensive guidelines for the effective use of ultrasonic microneedle patches, potentially shifting the paradigm in patient care and enhancing the overall quality of life.


Asunto(s)
Biopelículas , Sistemas de Liberación de Medicamentos , Agujas , Staphylococcus aureus , Sistemas de Liberación de Medicamentos/instrumentación , Sistemas de Liberación de Medicamentos/métodos , Staphylococcus aureus/fisiología , Ondas Ultrasónicas , Antibacterianos/administración & dosificación , Administración Cutánea
6.
BMEmat ; 2(1)2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38586163

RESUMEN

Multiphasic scaffolds with tailored gradient features hold significant promise for tissue regeneration applications. Herein, this work reports the transformation of two-dimensional (2D) layered fiber mats into three dimensional (3D) multiphasic scaffolds using a 'solids-of-revolution' inspired gas-foaming expansion technology. These scaffolds feature precise control over fiber alignment, pore size, and regional structure. Manipulating nanofiber mat layers and Pluronic F127 concentrations allows further customization of pore size and fiber alignment within different scaffold regions. The cellular response to multiphasic scaffolds demonstrates the number of cells migrated and proliferated onto the scaffolds are mainly dependent on the pore size rather than fiber alignment. In vivo subcutaneous implantation of multiphasic scaffolds to rats reveals substantial cell infiltration, neo tissue formation, collagen deposition, and new vessel formation within scaffolds, greatly surpassing the capabilities of traditional nanofiber mats. Histological examination indicates the importance of optimizing pore size and fiber alignment for promotion of cell infiltration and tissue regeneration. Overall, these scaffolds have potential applications in tissue modeling, studying tissue-tissue interactions, interface tissue engineering, and high-throughput screening for optimized tissue regeneration.

7.
Nat Nanotechnol ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684805

RESUMEN

Realizing the full potential of stretchable bioelectronics in wearables, biomedical implants and soft robotics necessitates conductive elastic composites that are intrinsically soft, highly conductive and strain resilient. However, existing composites usually compromise electrical durability and performance due to disrupted conductive paths under strain and rely heavily on a high content of conductive filler. Here we present an in situ phase-separation method that facilitates microscale silver nanowire assembly and creates self-organized percolation networks on pore surfaces. The resultant nanocomposites are highly conductive, strain insensitive and fatigue tolerant, while minimizing filler usage. Their resilience is rooted in multiscale porous polymer matrices that dissipate stress and rigid conductive fillers adapting to strain-induced geometry changes. Notably, the presence of porous microstructures reduces the percolation threshold (Vc = 0.00062) by 48-fold and suppresses electrical degradation even under strains exceeding 600%. Theoretical calculations yield results that are quantitatively consistent with experimental findings. By pairing these nanocomposites with near-field communication technologies, we have demonstrated stretchable wireless power and data transmission solutions that are ideal for both skin-interfaced and implanted bioelectronics. The systems enable battery-free wireless powering and sensing of a range of sweat biomarkers-with less than 10% performance variation even at 50% strain. Ultimately, our strategy offers expansive material options for diverse applications.

8.
ACS Omega ; 9(8): 9765-9781, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38434900

RESUMEN

Copper-cystine-based high aspect ratio structures (CuHARS) possess exceptional physical and chemical properties and exhibit remarkable biodegradability in human physiological conditions. Extensive testing has confirmed the biocompatibility and biodegradability of CuHARS under diverse biological conditions, making them a viable source of essential Cu2+. These ions are vital for catalyzing the production of nitric oxide (NO) from the decomposition of S-nitrosothiols (RSNOs) found in human blood. The ability of CuHARS to act as a Cu2+ donor under specific concentrations has been demonstrated in this study, resulting in the generation of elevated levels of NO. Consequently, this dual function makes CuHARS effective as both a bactericidal agent and a promoter of angiogenesis. In vitro experiments have shown that CuHARS actively promotes the migration and formation of complete lumens by redirecting microvascular endothelial cells. To maximize the benefits of CuHARS, they have been incorporated into biomimetic electrospun poly(ε-caprolactone)/gelatin nanofiber aerogels. Through the regulated release of Cu2+ and NO production, these channeled aerogels not only provide antibacterial support but also promote angiogenesis. Taken together, the inclusion of CuHARS in biomimetic scaffolds could hold great promise in revolutionizing tissue regeneration and wound healing.

9.
Nat Commun ; 15(1): 1080, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316777

RESUMEN

The structure and design flexibility of aerogels make them promising for soft tissue engineering, though they tend to come with brittleness and low elasticity. While increasing crosslinking density may improve mechanics, it also imparts brittleness. In soft tissue engineering, resilience against mechanical loads from mobile tissues is paramount. We report a hybrid aerogel that consists of self-reinforcing networks of micro- and nanofibers. Nanofiber segments physically entangle microfiber pillars, allowing efficient stress distribution through the intertwined fiber networks. We show that optimized hybrid aerogels have high specific tensile moduli (~1961.3 MPa cm3 g-1) and fracture energies (~7448.8 J m-2), while exhibiting super-elastic properties with rapid shape recovery (~1.8 s). We demonstrate that these aerogels induce rapid tissue ingrowth, extracellular matrix deposition, and neovascularization after subcutaneous implants in rats. Furthermore, we can apply them for engineering soft tissues via minimally invasive procedures, and hybrid aerogels can extend their versatility to become magnetically responsive or electrically conductive, enabling pressure sensing and actuation.


Asunto(s)
Nanofibras , Resiliencia Psicológica , Ratas , Animales , Nanofibras/química , Elasticidad , Ingeniería de Tejidos/métodos
10.
Macromol Biosci ; 24(5): e2300519, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38217528

RESUMEN

Wound biofilms pose a great clinical challenge. Herein, this work reports a dissolvable microneedle patch for dual delivery of monoclonal antibodies anti-PBP2a and engineers antimicrobial peptides W379. In vitro antibacterial efficacy testing with microneedle patches containing a combination of 250 ng mL-1 W379 and 250 ng mL-1 anti-BPB2a decreases the bacterial count from ≈3.31 × 107 CFU mL-1 to 1.28 × 102 CFU mL-1 within 2 h without eliciting evident cytotoxicity. Ex vivo testing indicates W379 and anti-PBP2a co-loaded microneedle patch displayed a remarkable reduction of bacterial load by ≈7.18 log CFU after administered only once within 48 h. The bacterial count is significantly diminished compared to the treatment by either W379 or anti-PBP2a-loaded alone microneedle patches. When administered twice within 48 h, no bacteria are identified. Further in vivo study also reveals that after two treatments of W379 and anti-PBP2a co-loaded PVP microneedle patches within 48 h, the bacterial colonies are undetectable in a type II diabetic mouse wound biofilm model. Taken together, W379 and anti-PBP2a co-loaded PVP microneedle patches hold great promise in treating wound biofilms.


Asunto(s)
Anticuerpos Monoclonales , Péptidos Antimicrobianos , Biopelículas , Agujas , Biopelículas/efectos de los fármacos , Animales , Ratones , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/administración & dosificación , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Humanos , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Sistemas de Liberación de Medicamentos , Cicatrización de Heridas/efectos de los fármacos , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Infección de Heridas/patología
11.
ACS Infect Dis ; 9(11): 2215-2225, 2023 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-37812567

RESUMEN

Identification of novel antibiotics is of top importance because of the threat of antibiotic-resistant pathogens. Antimicrobial screening in Mueller-Hinton broth is frequently the first step in antimicrobial discovery. Although widely utilized, this medium is not ideal as it could mask activity of candidates such as human cathelicidin LL-37 against methicillin-resistant Staphylococcus aureus (MRSA). This study identified a sensitive medium where LL-37 displayed excellent activity against numerous pathogens, including MRSA. Our screen of ultrashort overlapping LL-37 peptides in this medium led to the identification of KR-8, four residues shorter than KR-12. Hence, our screen condition may increase positive compound hits during antimicrobial screening. KR-8 provided an appealing template for us to design LL-37mini, which was potent against MRSA, Escherichia coli, and Pseudomonas aeruginosa but not toxic to mammalian cells. LL-37mini also inhibited bacterial attachment and biofilm formation and disrupted preformed biofilms in vitro and killed MRSA in murine wound biofilms in vivo. Consistent with membrane targeting, MRSA failed to develop resistance to LL-37mini in a multiple-passage experiment. Because LL-37mini can be made cost effectively, it can be developed into new antibiofilm and antimicrobial agents.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Animales , Humanos , Ratones , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Pruebas de Sensibilidad Microbiana , Antiinfecciosos/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Mamíferos
12.
Adv Sci (Weinh) ; 10(30): e2303259, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37632708

RESUMEN

Nitric oxide (NO) is a gaseous molecule that has a central role in signaling pathways involved in numerous physiological processes (e.g., vasodilation, neurotransmission, inflammation, apoptosis, and tumor growth). Due to its gaseous form, NO has a short half-life, and its physiology role is concentration dependent, often restricting its function to a target site. Providing NO from an external source is beneficial in promoting cellular functions and treatment of different pathological conditions. Hence, the multifaceted role of NO in physiology and pathology has garnered massive interest in developing strategies to deliver exogenous NO for the treatment of various regenerative and biomedical complexities. NO-releasing platforms or donors capable of delivering NO in a controlled and sustained manner to target tissues or organs have advanced in the past few decades. This review article discusses in detail the generation of NO via the enzymatic functions of NO synthase as well as from NO donors and the multiple biological and pathological processes that NO modulates. The methods for incorporating of NO donors into diverse biomaterials including physical, chemical, or supramolecular techniques are summarized. Then, these NO-releasing platforms are highlighted in terms of advancing treatment strategies for various medical problems.


Asunto(s)
Neoplasias , Óxido Nítrico , Humanos , Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/uso terapéutico , Donantes de Óxido Nítrico/química , Transducción de Señal , Materiales Biocompatibles/química , Gases
14.
J Control Release ; 356: 131-141, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36858263

RESUMEN

Biofilms pose a great challenge for wound management. Herein, this study describes a near-infrared (NIR) light-responsive microneedle patch for on-demand release of antimicrobial peptide for treatment of wound biofilms. IR780 iodide as a photothermal conversion agent and molecularly engineered peptide W379 as an antimicrobial agent are loaded in dissolvable poly(vinylpyrrolidone) (PVP) microneedle patches followed by coating with a phase change material 1-tetradecanol (TD). After placing in an aqueous solution or biofilm containing wounds ex vivo and in vivo, upon exposure to NIR light, the incorporated IR780 induces light-to-heat conversion, causing the melting of TD. This leads to the dissolution of PVP microneedles, enabling the release of loaded W379 peptide from the microneedles into surrounding regions (e.g., solution, biofilm, wound bed). Compared with traditional microneedle patches, NIR light responsive microneedle patches can program the release of antimicrobial peptide and show high antibacterial efficacy in vitro. Meanwhile, this work indicates that NIR light responsive TD-coated, W379-loaded PVP microneedle patches show excellent antibiofilm activities ex vivo and in vivo. Additionally, this microneedle system could be a promising platform for delivering other antimicrobial agents.


Asunto(s)
Antiinfecciosos , Péptidos Antimicrobianos , Sistemas de Liberación de Medicamentos , Administración Cutánea , Biopelículas
15.
Adv Funct Mater ; 33(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36714167

RESUMEN

Fast healing of diabetic wounds remains a major clinical challenge. Herein, this work reports a strategy to combine nanofiber aerogels containing precision macrochannels and the LL-37-mimic peptide W379 for rapid diabetic wound healing. Nanofiber aerogels consisting of poly(glycolide-co-lactide) (PGLA 90:10)/gelatin and poly-p-dioxanone (PDO)/gelatin short electrospun fiber segments were prepared by partially anisotropic freeze-drying, crosslinking, and sacrificial templating with three-dimensional (3D)-printed meshes, exhibiting nanofibrous architecture and precision micro-/macrochannels. Like human cathelicidin LL-37, W379 peptide at a concentration of 3 µg/mL enhanced the migration and proliferation of keratinocytes and dermal fibroblasts in a cell scratch assay and a proliferation assay. In vivo studies show that nanofiber aerogels with precision macrochannels can greatly promote cell penetration compared to aerogels without macrochannels. Relative to control and aerogels with and without macrochannels, adding W379 peptides to aerogels with precision macrochannels shows the best efficacy in healing diabetic wounds in mice in terms of cell infiltration, neovascularization, and re-epithelialization. The fast re-epithelization could be due to upregulation of phospho-extracellular signal-regulated kinase (p38 MAPK) after treatment with W379. Together, the approach developed in this work could be promising for the treatment of diabetic wounds and other chronic wounds.

16.
Adv Biol (Weinh) ; 7(8): e2200227, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36709421

RESUMEN

Regeneration and functional recovery of the damaged nerve are challenging due to the need for effective therapeutic drugs, biomaterials, and approaches. The poor outcome of the treatment of nerve injury stems from the incomplete understanding of axonal biology and interactions between neurons and the surrounding environment, such as glial cells and extracellular matrix. Microfluidic devices, in combination with various injury techniques, have been applied to test biological hypotheses in nerve injury and nerve regeneration. The microfluidic devices provide multiple advantages over the in vitro cell culture on a petri dish and in vivo animal models because a specific part of the neuronal environment can be manipulated using physical and chemical interventions. In addition, single-cell behavior and interactions between neurons and glial cells can be visualized and quantified on microfluidic platforms. In this article, current in vitro nerve injury models on a chip that mimics in vivo axonal injuries and the regeneration process of axons are summarized. The microfluidic-based nerve injury models could enhance the understanding of the physiological and pathophysiological mechanisms of nerve tissues and simultaneously serve as powerful drug and biomaterial screening platforms.


Asunto(s)
Axones , Traumatismos del Sistema Nervioso , Animales , Axones/fisiología , Neuronas/fisiología , Microfluídica , Técnicas de Cultivo de Célula/métodos , Dispositivos Laboratorio en un Chip
17.
Sci Adv ; 9(1): eadf0575, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36608138

RESUMEN

Liquid metal-elastomer composite is a promising soft conductor for skin-interfaced bioelectronics, soft robots, and others due to its large stretchability, ultrasoftness, high electrical conductivity, and mechanical-electrical decoupling. However, it often suffers from deformation-induced leakage, which can smear skin, deteriorate device performance, and cause circuit shorting. Besides, antimicrobial property is desirable in soft conductors to minimize microbial infections. Here, we report phase separation-based synthesis of porous liquid metal-elastomer composites with high leakage resistance and antimicrobial property, together with large stretchability, tissue-like compliance, high and stable electrical conductivity over deformation, high breathability, and magnetic resonance imaging compatibility. The porous structures can minimize leakage through damping effects and lower percolation thresholds to reduce liquid metal usage. In addition, epsilon polylysine is loaded into elastic matrices during phase separation to provide antimicrobial property. The enabled skin-interfaced bioelectronics can monitor cardiac electrical and mechanical activities and offer electrical stimulations in a mechanically imperceptible and electrically stable manner even during motions.

18.
Adv Wound Care (New Rochelle) ; 12(7): 399-427, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36301918

RESUMEN

Significance: Nowadays, the wound dressing is no longer limited to its primary wound protection ability. Hydrogel, sponge-like material, three dimensional-printed mesh, and nanofiber-based dressings with incorporation of functional components, such as nanomaterials, growth factors, enzymes, antimicrobial agents, and electronics, are able to not only prevent/treat infection but also accelerate the wound healing and monitor the wound-healing status. Recent Advances: The advances in nanotechnologies and materials science have paved the way to incorporate various functional components into the dressings, which can facilitate wound healing and monitor different biological parameters in the wound area. In this review, we mainly focus on the discussion of recently developed functional wound dressings. Critical Issues: Understanding the structure and composition of wound dressings is important to correlate their functions with the outcome of wound management. Future Directions: "All-in-one" dressings that integrate multiple functions (e.g., monitoring, antimicrobial, pain relief, immune modulation, and regeneration) could be effective for wound repair and regeneration.


Asunto(s)
Pie Diabético , Nanofibras , Humanos , Vendas Hidrocoloidales , Cicatrización de Heridas , Hidrogeles
19.
Adv Mater ; 35(5): e2207335, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36444871

RESUMEN

Drawing inspiration for biomaterials from biological systems has led to many biomedical innovations. One notable bioinspired device, Velcro, consists of two substrates with interlocking ability. Generating reversibly interlocking biomaterials is an area of investigation, as such devices can allow for modular tissue engineering, reversibly interlocking biomaterial interfaces, or friction-based coupling devices. Here, a biaxially interlocking interface generated using electrostatic flocking is reported. Two electrostatically flocked substrates are mechanically and reversibly interlocked with the ability to resist shearing and compression forces. An initial high-throughput screen of polyamide flock fibers with varying diameters and fiber lengths is conducted to elucidate the roles of different fiber parameters on scaffold mechanical properties. After determining the most desirable parameters via weight scoring, polylactic acid (PLA) fibers are used to emulate the ideal scaffold for in vitro use. PLA flocked scaffolds are populated with osteoblasts and interlocked. Interlocked flocked scaffolds improved cell survivorship under mechanical compression and sustained cell viability and proliferation. Additionally, the compression and shearing resistance of cell-seeded interlocking interfaces increased with increasing extracellular matrix deposition. The introduction of extracellular matrix-reinforced interlocking interfaces may serve as binders for modular tissue engineering, act as scaffolds for engineering tissue interfaces, or enable friction-based couplers for biomedical applications.


Asunto(s)
Materiales Biocompatibles , Andamios del Tejido , Andamios del Tejido/química , Materiales Biocompatibles/química , Ingeniería de Tejidos , Poliésteres/química , Matriz Extracelular/química
20.
Mol Pharm ; 20(1): 738-749, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36485036

RESUMEN

Peptide stability to proteases has been a major requirement for developing peptide therapeutics. This study investigates the effects of peptide stability on antimicrobial and antibiofilm activity under various conditions. For this purpose, two human cathelicidin-derived peptides differing in stability to proteases were utilized. While GF-17, a peptide derived from the major antimicrobial region of human LL-37, can be rapidly cleaved by proteases, the engineered peptide 17BIPHE2 is resistant to multiple proteases. In the standard antimicrobial susceptibility, killing kinetics, and membrane permeabilization assays conducted in vitro using planktonic bacteria, these two peptides displayed similar potency. The two peptides were also similarly active against methicillin-resistant Staphylococcus aureus (MRSA) USA300 prior to biofilm formation. However, 17BIPHE2 was superior to GF-17 in disrupting preformed biofilms probably due to both enhanced stability and slightly higher DNA binding capacity. In a wax moth model, 17BIPHE2 better protected insects from MRSA infection-caused death than GF-17, consistent with the slower degradation of 17BIPHE2 than GF-17. Here, peptide antimicrobial activity was found to be critical for in vivo efficacy. When incorporated in the nanofiber/microneedle delivery device, GF-17 and 17BIPHE2 displayed a similar effect in eliminating MRSA in murine chronic wounds, underscoring the advantage of nanofibers in protecting the peptide from degradation. Since nanoformulation can ease the requirement of peptide stability, it opens the door to a direct use of natural peptides or their cocktails for antimicrobial treatment, accelerating the search of effective antibiofilm peptides to treat chronic wounds.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Humanos , Animales , Ratones , Péptidos Catiónicos Antimicrobianos/farmacología , Antiinfecciosos/farmacología , Péptido Hidrolasas , Biopelículas , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana
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