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1.
Adv Healthc Mater ; : e2400884, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701326

RESUMO

Bacterial infection, inflammation, and excessive oxidative stress are the primary factors that contribute to delayed healing of skin wounds. In this study, a multifunctional wound dressing (SF/Ag@rGO hydrogel) is developed to promote the healing of infected skin wounds by combining the inherent antibacterial activity of Ag nanoparticles (NPs) with near-infrared (NIR)-assisted antibacterial therapy. Initially, L-ascorbic acid is used as a reducing agent and PVP-K17 as a stabilizer and dispersant, this facilitates the synthesis of reduced graphene oxide loaded with Ag NPs (Ag@rGO). Ag@rGO is then blended with a silk fibroin (SF) solution to form an instantly gelling SF/Ag@rGO hydrogel that exhibits rapid self-healing, injectability, shape adaptability, NIR responsiveness, antioxidant, high tissue adhesion, and robust mechanical properties. In vitro and in vivo experiments show that the SF/Ag@rGO hydrogel demonstrates strong antioxidant and photothermal antibacterial capabilities, promoting wound healing through angiogenesis, stimulating collagen generation, alleviating inflammation, antioxidant, and promoting cell proliferation, indicating that the SF/Ag@rGO hydrogel dressing is an ideal candidate for clinical treatment of full-thickness bacterial-stained wounds.

2.
ACS Appl Mater Interfaces ; 16(11): 13563-13572, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38449378

RESUMO

Antibacterial hydrogels have emerged as a promising approach for effective wound treatment. However, despite extensive research on the fabrication of antibacterial hydrogels, it remains challenging to develop injectable, biocompatible, transparent, and mass-producible hydrogels with antibacterial properties. In this study, we successfully fabricated an antibacterial drug-loaded composite hydrogel, named CC45/OKG40/HS, through a Schiff base reaction between carboxymethyl chitosan (CC) and oxidized konjac glucomannan (OKG), followed by the encapsulation of stevioside-stabilized honokiol (HS) micelles. The CC45/OKG40/HS hydrogel exhibited several favorable properties, including a short gel time (<10 min), high water content (>92%), injectability, good adhesiveness, self-healing ability, and high transparency. In vitro experiments confirmed its excellent antibacterial properties, antioxidant activities, and high biocompatibility (no cytotoxicity, hemolysis ratio <5%). Furthermore, in vivo evaluation demonstrated that the CC45/OKG40/HS0.5 hydrogel accelerated wound healing by relieving inflammatory responses and enhancing re-epithelization. Given its feasibility for mass production, the findings showed that the CC45/OKG40/HS hydrogel has the potential as an advanced antibacterial wound dressing for commercial use.


Assuntos
Quitosana , Mananas , Quitosana/farmacologia , Hidrogéis/farmacologia , Micelas , Cicatrização , Antibacterianos/farmacologia
3.
ACS Appl Mater Interfaces ; 15(42): 48952-48962, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37843040

RESUMO

Excessive oxidative stress, bacterial infections, and inflammation are the primary factors impeding the healing of skin wounds. Bioactive hydrogels are commonly employed in the treatment of skin injuries. However, the limited solubility of many drugs and active agents in water significantly hampers their effectiveness in hydrogel dressings. In this research, prior to incorporation into the silk fibroin (SF) hydrogel matrix, two active agents curcumin and silver nanoparticles (Ag NPs) were decorated by silk sericin to improve their dispersibility and stability in water. The resultant SF/Ag/C hydrogels combined the biological safety and nontoxicity of SF, the antioxidant and anti-inflammatory efficacy of curcumin, and the antibacterial effect of Ag NPs. These properties effectively enhanced wound repair by reducing bacterial infections, mitigating oxidative stress, suppressing the expression of pro-inflammatory factors, and promoting angiogenesis. This study presented a straightforward approach for constructing bioactive hydrogels for the promotion of the wound healing process.


Assuntos
Infecções Bacterianas , Curcumina , Fibroínas , Nanopartículas Metálicas , Sericinas , Humanos , Seda , Sericinas/farmacologia , Hidrogéis/farmacologia , Curcumina/farmacologia , Prata/farmacologia , Fibroínas/farmacologia , Antibacterianos , Bandagens , Água
4.
J Mater Chem B ; 11(41): 9950-9960, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37830374

RESUMO

Uncontrollable bleeding is a crucial factor that can lead to fatality. Therefore, the development of hemostatic dressings that enable rapid hemostasis is of utmost importance. Hydrogels with injectability, self-healing ability, and adhesiveness hold significant potential as effective hemostatic dressings. Herein, a composite hydrogel was fabricated by the oxidized Konjac glucomannan and ε-polylysine. After the encapsulation of a hemostatic drug, etamsylate, an oxidized Konjac glucomannan/ε-polylysine/etamsylate (OKGM/PL/E) composite hydrogel that possesses favorable properties including injectability, self-healing ability, tissue adhesiveness, hemocompatibility and cytocompatibility was fabricated. The OKGM/PL/E hydrogel demonstrated the ability to effectively adhere red blood cells and seal wounds, enabling rapid control of hemorrhaging. In vivo wound healing experiments confirmed the hemostatic and wound healing efficacy of the OKGM/PL/E hydrogel, highlighting its potential as a valuable hemostatic dressing.


Assuntos
Quitosana , Etamsilato , Hemostáticos , Etamsilato/farmacologia , Polilisina/farmacologia , Quitosana/farmacologia , Hidrogéis/farmacologia , Cicatrização , Hemostasia , Hemostáticos/farmacologia
5.
Lang Cogn Neurosci ; 35(5): 658-679, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617349

RESUMO

Language understanding requires the integration of the input with preceding context. Event-related potentials (ERPs) have contributed significantly to our understanding of what contextual information is accessed and when. Much of this research has, however, been limited to experimenter-designed stimuli with highly atypical lexical and context statistics. This raises questions about the extent to which previous findings generalize to everyday language processing of natural stimuli with typical linguistic statistics. We ask whether context can affect ERPs over natural stimuli early, before the N400 time window. We re-analyzed a data set of ERPs over ~700 visually presented content words in sentences from English novels. To increase power, we employed linear mixed effects regression simultaneously modeling random variance by subject and by item. To reduce concerns about Type I error inflation common to any type of time series analysis, we introduced a simple approach to model and discount auto-correlations at multiple, empirically determined, time lags. We compared this approach to Bonferroni correction. Planned follow-up analyses used Generalized Additive Mixture Models to assess the linearity of contextual effects, including lexical surprisal, found within the N400 time window. We found that contextual information affects ERPs in both early (~200ms after word onset) and late (N400) time windows, supporting a cascading, interactive account of lexical access.

6.
J Biosci Bioeng ; 126(3): 389-396, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29685821

RESUMO

Treating full-layer injury of bone and cartilage is currently a significant challenge in orthopedic trauma repair. Joint damage typically includes chondral defects, and the underlying subchondral defect sites are difficult to repair. Tissue engineering technology could potentially be used to treat such injuries; however, results to date been unsatisfactory. The aim of this study was to design a multilayer composite scaffold containing cartilage, bone, and calcified layers to simulate physiological full-thickness bone-cartilage structure. The cartilage layer was created using an improved temperature-gradient thermally induced crystallization technology. The bone and calcified layers were synthesized using 3D printing technology. We examined the scaffold by using scanning electron microscope (SEM), X-ray diffraction (XRD), fluorescence staining, and micro computed tomography (Micro-CT), and observed clearly oriented structures in the cartilage layer, overlapping structures in the bone scaffold, and a compressed calcified layer. Biomechanical performance testing showed that the scaffolds were significantly stronger than scaffolds without a calcified layer (traditional scaffolds) in maximum tensile strength and maximum shear strength (P < 0.05). After inoculating cells onto the scaffolds, we observed similar cell adherence and proliferation to that observed in traditional scaffolds, likely because of the high porosity of the whole scaffold. Our scaffolds could be used in bone and cartilage full-thickness injury repair methods, as well as applications in the field of tissue engineering.


Assuntos
Osso e Ossos/citologia , Cálcio/química , Cartilagem Articular/citologia , Cartilagem/citologia , Técnicas de Cultura de Células , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Osso e Ossos/fisiologia , Cartilagem/fisiologia , Cartilagem Articular/fisiologia , Bovinos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Proliferação de Células , Forma Celular , Células Cultivadas , Masculino , Teste de Materiais , Fenômenos Mecânicos , Porosidade , Impressão Tridimensional , Propriedades de Superfície , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos , Microtomografia por Raio-X
7.
Crit Rev Eukaryot Gene Expr ; 27(3): 211-217, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199606

RESUMO

Although it has been suggested that the interleukin-6(IL-6) gene -597G/A polymorphism may be a risk factor for cancer, the conclusions from previous studies are inconsistent. To clarify the precise interrelation, we performed a comprehensive meta-analysis of 6 case-control studies involving 1,605 subjects (706 cases and 899 controls). The overall results showed no significant association between the IL6 -597G/A polymorphism and cancer risk in the overall population (CC vs GG: OR = 2.38, 95% CI = 0.62-9.14; CG vs GG: OR = 1.23, 95% CI = 0.66-2.27; dominant model: OR = 1.32, 95% CI = 0.63-2.79; recessive model: OR = 1.93, 95% CI = 0.72-v5.17). Subgroup analysis by ethnicity and cancer type yielded the same result. Therefore, the current evidence from this meta-analysis did not support the hypothesis of IL-6 -597G/A polymorphism as a risk factor of cancer. Conclusive evidence on the effects of this variant in cancer should be addressed in future studies.


Assuntos
Predisposição Genética para Doença , Interleucina-6/genética , Neoplasias/genética , Povo Asiático , Humanos , Neoplasias/patologia , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
8.
Cogn Affect Behav Neurosci ; 16(1): 72-92, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26311442

RESUMO

In two experiments, we examined the contribution of articulation-specific features to visual word recognition during the reading of Chinese. In spoken Standard Chinese, a syllable with a full tone can be tone-neutralized through sound weakening and pitch contour change, and there are two types of two-character compound words with respect to their articulation variation. One type requires articulation of a full tone for each constituent character, and the other requires a full- and a neutral-tone articulation for the first and second characters, respectively. Words of these two types with identical first characters were selected and embedded in sentences. Native speakers of Standard Chinese were recruited to read the sentences. In Experiment 1, the individual words of a sentence were presented serially at a fixed pace while event-related potentials were recorded. This resulted in less-negative N100 and anterior N250 amplitudes and in more-negative N400 amplitudes when targets contained a neutral tone. Complete sentences were visible in Experiment 2, and eye movements were recorded while participants read. Analyses of oculomotor activity revealed shorter viewing durations and fewer refixations on-and fewer regressive saccades to-target words when their second syllable was articulated with a neutral rather than a full tone. Together, the results indicate that readers represent articulation-specific word properties, that these representations are routinely activated early during the silent reading of Chinese sentences, and that the representations are also used during later stages of word processing.


Assuntos
Potenciais Evocados/fisiologia , Movimentos Oculares/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Leitura , Adulto , Povo Asiático , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Semântica , Adulto Jovem
9.
J Exp Psychol Hum Percept Perform ; 41(4): 958-76, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25915072

RESUMO

Recent Electroencephalography/Magnetoencephalography (EEG/MEG) studies suggest that when contextual information is highly predictive of some property of a linguistic signal, expectations generated from context can be translated into surprisingly low-level estimates of the physical form-based properties likely to occur in subsequent portions of the unfolding signal. Whether form-based expectations are generated and assessed during natural reading, however, remains unclear. We monitored eye movements while participants read phonologically typical and atypical nouns in noun-predictive contexts (Experiment 1), demonstrating that when a noun is strongly expected, fixation durations on first-pass eye movement measures, including first fixation duration, gaze duration, and go-past times, are shorter for nouns with category typical form-based features. In Experiments 2 and 3, typical and atypical nouns were placed in sentential contexts normed to create expectations of variable strength for a noun. Context and typicality interacted significantly at gaze duration. These results suggest that during reading, form-based expectations that are translated from higher-level category-based expectancies can facilitate the processing of a word in context, and that their effect on lexical processing is graded based on the strength of category expectancy.


Assuntos
Antecipação Psicológica/fisiologia , Movimentos Oculares/fisiologia , Idioma , Reconhecimento Visual de Modelos/fisiologia , Leitura , Adulto , Medições dos Movimentos Oculares , Humanos , Adulto Jovem
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