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1.
ACS Appl Mater Interfaces ; 16(26): 33135-33148, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38900923

RESUMEN

Atopic dermatitis (AD), a chronic skin condition characterized by itching, redness, and inflammation, is closely associated with heightened levels of endogenous reactive oxygen species (ROS) in the skin. ROS can contribute to the onset and progression of AD through oxidative stress, which leads to the release of proinflammatory cytokines, T-cell differentiation, and the exacerbation of skin symptoms. In this study, we aim to develop a therapeutic antioxidant hydrogel patch for the potential treatment of AD using lignin, a biomass waste material. Lignin contains polyphenol groups that enable it to scavenge ROS and exhibit antioxidant properties. The lignin hydrogel patches, possessing optimized mechanical properties through the control of the lignin and cross-linker ratio, demonstrated high ROS-scavenging capabilities. Furthermore, the lignin hydrogel demonstrated excellent biocompatibility with the skin, exhibiting beneficial properties in protecting human keratinocytes under high oxidative conditions. When applied to an AD mouse model, the hydrogel patch effectively reduced epidermal thickness in inflamed regions, decreased mast cell infiltration, and regulated inflammatory cytokine levels. These findings collectively suggest that lignin serves as a therapeutic hydrogel patch for managing AD by modulating oxidative stress through its ROS-scavenging ability.


Asunto(s)
Antioxidantes , Dermatitis Atópica , Hidrogeles , Lignina , Estrés Oxidativo , Piel , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/patología , Lignina/química , Lignina/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Ratones , Humanos , Hidrogeles/química , Hidrogeles/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Piel/efectos de los fármacos , Piel/patología , Piel/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Citocinas/metabolismo
2.
ACS Appl Mater Interfaces ; 16(26): 33106-33120, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38906850

RESUMEN

The scavenging ability of cerium oxide nanoparticles (CeNPs) for reactive oxygen species has been intensively studied in the field of catalysis. However, the immunological impact of these particles has not yet been thoroughly investigated, despite intensive research indicating that modulation of the reactive oxygen species could potentially regulate cell fate and adaptive immune responses. In this study, we examined the intrinsic capability of CeNPs to induce tolerogenic dendritic cells via their reactive oxygen species-scavenging effect when the autoantigenic peptides were simply mixed with CeNPs. CeNPs effectively reduced the intracellular reactive oxygen species levels in dendritic cells in vitro, leading to the suppression of costimulatory molecules as well as NLRP3 inflammasome activation, even in the presence of pro-inflammatory stimuli. Subcutaneously administrated PEGylated CeNPs were predominantly taken up by antigen-presenting cells in lymph nodes and to suppress cell maturation in vivo. The administration of a mixture of PEGylated CeNPs and myelin oligodendrocyte glycoprotein peptides, a well-identified autoantigen associated with antimyelin autoimmunity, resulted in the generation of antigen-specific Foxp3+ regulatory T cells in mouse spleens. The induced peripheral regulatory T cells actively inhibited the infiltration of autoreactive T cells and antigen-presenting cells into the central nervous system, ultimately protecting animals from experimental autoimmune encephalomyelitis when tested using a mouse model mimicking human multiple sclerosis. Overall, our findings reveal the potential of CeNPs for generating antigen-specific immune tolerance to prevent multiple sclerosis, opening an avenue to restore immune tolerance against specific antigens by simply mixing the well-identified autoantigens with the immunosuppressive CeNPs.


Asunto(s)
Cerio , Células Dendríticas , Encefalomielitis Autoinmune Experimental , Tolerancia Inmunológica , Nanopartículas , Péptidos , Especies Reactivas de Oxígeno , Cerio/química , Cerio/farmacología , Animales , Especies Reactivas de Oxígeno/metabolismo , Ratones , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Nanopartículas/química , Células Dendríticas/inmunología , Células Dendríticas/efectos de los fármacos , Tolerancia Inmunológica/efectos de los fármacos , Péptidos/química , Péptidos/farmacología , Péptidos/inmunología , Ratones Endogámicos C57BL , Autoantígenos/inmunología , Autoantígenos/química , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Femenino , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología
3.
Heliyon ; 10(8): e29030, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38638954

RESUMEN

Diabetes is a chronic metabolic disorder characterized by elevated blood glucose levels, posing significant health risks such as cardiovascular disease, and nerve, kidney, and eye damage. Effective management of blood glucose is essential for individuals with diabetes to mitigate these risks. This study introduces the Glu-Ensemble, a deep learning framework designed for precise blood glucose forecasting in patients with type 2 diabetes. Unlike other predictive models, Glu-Ensemble addresses challenges related to small sample sizes, data quality issues, reliance on strict statistical assumptions, and the complexity of models. It enhances prediction accuracy and model generalizability by utilizing larger datasets and reduces bias inherent in many predictive models. The framework's unified approach, as opposed to patient-specific models, eliminates the need for initial calibration time, facilitating immediate blood glucose predictions for new patients. The obtained results indicate that Glu-Ensemble surpasses traditional methods in accuracy, as measured by root mean square error, mean absolute error, and error grid analysis. The Glu-Ensemble framework emerges as a promising tool for blood glucose level prediction in type 2 diabetes patients, warranting further investigation in clinical settings for its practical application.

4.
Comput Biol Med ; 173: 108257, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38520922

RESUMEN

We developed an attention model to predict future adverse glycemic events 30 min in advance based on the observation of past glycemic values over a 35 min period. The proposed model effectively encodes insulin administration and meal intake time using Time2Vec (T2V) for glucose prediction. The proposed impartial feature selection algorithm is designed to distribute rewards proportionally according to agent contributions. Agent contributions are calculated by a step-by-step negation of updated agents. Thus, the proposed feature selection algorithm optimizes features from electronic medical records to improve performance. For evaluation, we collected continuous glucose monitoring data from 102 patients with type 2 diabetes admitted to Cheonan Hospital, Soonchunhyang University. Using our proposed model, we achieved F1-scores of 89.0%, 60.6%, and 89.8% for normoglycemia, hypoglycemia, and hyperglycemia, respectively.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipoglucemia , Humanos , Hipoglucemiantes , Glucemia , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Automonitorización de la Glucosa Sanguínea , Hipoglucemia/inducido químicamente , Insulina
5.
Biomacromolecules ; 25(4): 2597-2606, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38483111

RESUMEN

The development of highly effective hemostatic materials with high biocompatibility and outstanding performance is vital to the field of biomaterials. In this study, we develop a hemostatic fiber material that exhibits high biocompatibility and excellent performance. By incorporating polydopamine (PDA) into the alkaline treatment of silk fibroin (SF), we achieve PDA-coated SF fibers with lengths that can be controlled by the alkaline concentration. The PDA coating significantly enhances the hemostatic ability of the silk fibers and exhibits superior performance in both in vitro and ex vivo experiments. By performing animal studies involving a mouse liver puncture model and a femoral vein incision model, we demonstrate the remarkable hemostatic capability of the PDA-coated SF fibers, as evidenced by the lower blood loss compared to that of a commercial hemostat powder. These findings highlight the potential of applying a PDA-assisted alkaline treatment to SF fibers to efficiently create hemostatic fibers with controllable lengths, which would be promising candidates for clinical hemostatic applications.


Asunto(s)
Fibroínas , Hemostáticos , Indoles , Ratones , Animales , Seda , Hemostáticos/farmacología , Polímeros/farmacología , Materiales Biocompatibles , Fibroínas/farmacología
6.
Biomacromolecules ; 25(2): 1153-1161, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38290478

RESUMEN

The skin, a crucial organ that protects the body, is vulnerable to external damage. Traditional tissue regeneration methods, including bulk hydrogels, aim to facilitate wound healing by interacting with host cells and providing a conducive environment. However, the nanoscale porosity of conventional hydrogels limits cell penetration and tissue regeneration. To overcome this, hydrogels composed of microgels have emerged as promising alternatives. In this study, we propose a granular hydrogel using decellularized tilapia skin. The tilapia skin-based microgels are cost-effective, immune-friendly, and have a high collagen content. Microgels based on the decellularized extracellular matrix of tilapia were successfully fabricated by using microfluidics. Through the assembly of these microgels using adhesive hyaluronic acid-catechol, the resulting 3D granular hydrogel scaffold facilitated enhanced cell growth, accelerated cell differentiation, and successful healing of full-thickness wounds in a mouse model. This study reveals the potential of tilapia skin-based granular hydrogel assembly in wound healing, overcoming conventional hydrogel limits.


Asunto(s)
Microgeles , Tilapia , Ratones , Animales , Hidrogeles/farmacología , Cicatrización de Heridas , Piel
7.
Adv Mater ; 36(13): e2306602, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38091378

RESUMEN

Single-atom nanozymes (SAzymes) constitute a promising category of enzyme-mimicking materials with outstanding catalytic performance. The performance of SAzymes improves through modification of the coordination environments around the metal center. However, the catalytic turnover rates of SAzymes, which are key measures of the effectiveness of active site modifications, remain lower than those of natural enzymes, especially in peroxidase-reactions. Here, the first and second shell coordination tuning strategy that yields SAzymes with structures and activities analogous to those of natural enzymes is reported. The optimized SAzyme exhibits a turnover rate of 52.7 s-1 and a catalytic efficiency of 6.97 × 105 M-1 s-1. A computational study reveals that axial S-ligands induce an alternative reaction mechanism, and SO2- functional groups provide hydrogen bonds to reduce the activation energy. In addition, SAzyme shows superior anti-tumor ability in vitro and in vivo. These results demonstrate the validity of coordination engineering strategies and the carcinostatic potential of SAzymes.


Asunto(s)
Carbono , Hierro , Hierro/química , Carbono/química , Catálisis
8.
Macromol Biosci ; 24(1): e2300533, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38050925
9.
Small ; 20(19): e2309217, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38133489

RESUMEN

Many existing synthetic hydrogels are inappropriate for repetitive motions because of large hysteresis, and their mechanical properties in warm and saline physiological conditions remain understudied. In this study, a stretch-rate-independent, hysteresis-free, elastic, and tough nanocomposite hydrogel that can maintain its mechanical properties in phosphate-buffered saline of 37 °C similar to warm and saline conditions of the human body is developed. The strength, stiffness, and toughness of the hydrogel are simultaneously reinforced by biomimetic silica nanoparticles with a surface of embedded circular polyamine chains. Such distinctive surfaces form robust interfacial interactions by local topological folding/entanglement with the polymer chains of the matrix. Load transfer from the soft polymer matrix to stiff nanoparticles, along with the elastic sliding/unfolding/disentanglement of polymer chains, overcomes the traditional trade-off between strength/stiffness and toughness and allows for hysteresis-free, strain-rate-independent, and elastic behavior. This robust reinforcement is sustained in warm phosphate-buffered saline. These properties demonstrate the application potential of the developed hydrogel as a soft, elastic, and tough bio-strain sensor that can detect dynamic motions across various deformation speeds and ranges. The findings provide a simple yet effective approach to developing practical hydrogels with a desirable combination of strength/stiffness and toughness, in a fully swollen and equilibrated state.

10.
ACS Nano ; 17(23): 24404-24416, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38039189

RESUMEN

Inflammatory bowel disease (IBD) is characterized by an inappropriate and persistent inflammatory immune response and is often accompanied by excessive reactive oxygen species (ROS) production. For effective IBD treatment, there is a high demand for safe and targeted therapy that can be orally administered. In this study, we aimed to propose the use of inflamed colon-targeted antioxidant nanotherapeutics (ICANs) for in situ oxidative stress level modulation in colitis. ICANs consist of mesoporous silica nanoparticles (MSNs) with surface-attached ROS-scavenging ceria nanoparticles (CeNPs), which are further coated with poly(acrylic acid) (PAA) to facilitate preferential adherence to inflamed colon tissues through electrostatic interaction. We achieved a high ROS-scavenging property that remained effective even after artificial gastrointestinal fluid incubation by optimization of the molecular weight and PAA-coating pH. The orally administered ICANs demonstrated enhanced adherence to inflamed colon tissues in an acute inflammation mouse model of IBD induced by dextran sulfate sodium. This targeted delivery resulted in gut microenvironment modulation by regulating redox balance and reducing inflammatory cell infiltration, thereby suppressing the colitis-associated immune response. These findings highlight the potential of noninvasive ICANs as a promising candidate for treating inflammatory intestinal diseases by oxidative stress level modulation in colitis.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Colon/metabolismo , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Estrés Oxidativo , Oxidación-Reducción , Antioxidantes/farmacología , Modelos Animales de Enfermedad
11.
ACS Nano ; 17(24): 24696-24709, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38051295

RESUMEN

Multiple sclerosis (MS) is a demyelinating autoimmune disease, in which the immune system attacks myelin. Although systemic immunosuppressive agents have been used to treat MS, long-term treatment with these drugs causes undesirable side effects such as altered glucose metabolism, insomnia, and hypertension. Herein, we propose a tolerogenic therapeutic vaccine to treat MS based on lignin nanoparticles (LNP) with intrinsic reactive oxygen species (ROS)-scavenging capacity derived from their phenolic moieties. The LNP loaded with autoantigens of MS allowed for inducing tolerogenic DCs with low-level expression of costimulatory molecules while presenting antigenic peptides. Intravenous injection of an LNP-based tolerogenic vaccine into an experimental autoimmune encephalomyelitis (EAE) model led to durable antigen-specific immune tolerance via inducing regulatory T cells (Tregs). Autoreactive T helper type 1 cells, T helper type 17 cells, and inflammatory antigen presentation cells (APCs) were suppressed in the central nervous system (CNS), ameliorating ongoing MS in early and late disease states. Additionally, the incorporation of dexamethasone into an LNP-based tolerogenic nanovaccine could further improve the recovery of EAE mice in the severe chronic stage. As lignin is the most abundant biomass and waste byproduct in the pulping industry, a lignin-based tolerogenic vaccine could be a novel, cost-effective, high-value vaccine platform with potent therapeutic efficiency in treating autoimmune diseases.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Vacunas , Ratones , Animales , Esclerosis Múltiple/tratamiento farmacológico , Nanovacunas , Lignina/uso terapéutico , Especies Reactivas de Oxígeno/uso terapéutico , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Ratones Endogámicos C57BL
12.
Heliyon ; 9(12): e23231, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38149193

RESUMEN

The Korea Baseball Organization (KBO) introduced the foreign player system in 1998 to enhance league competitiveness. In 2014, the number of foreign players increased to three per team. Since then, the ten KBO teams have routinely included two foreign pitchers and one batter. While the performance of foreign players significantly impacts the post-season qualification of the team, the contract renewal rates for pitchers and batters are only 34 % and 36 %, respectively. Therefore, a method that can aid in the contract renewal decision can help teams recruit high-caliber foreign players, improve their performance, raise the level of KBO league, and provide an enjoyable experience for baseball fans. In this study, we use machine learning methods to predict the contract renewal decision and compare the prediction performances of various models. We use data on foreign player performances in the Minor League Baseball and Major League Baseball immediately prior to joining KBO, in KBO upon joining, and player image data. By comparing the accuracy, area under the receiver-operating characteristic curve, and precision of prediction results based on performance in each league, we find that performance in KBO plays a significant role in improving the prediction. Additionally, a post-hoc analysis of batters reveals a gradual decline in the performance level of foreign batters who succeeded in KBO, which is found to be related to the results of international baseball tournaments. In conclusion, the proposed approach to player performance evaluation and contract renewal decisions can contribute to the long-term success of the teams and league.

13.
Nanomicro Lett ; 16(1): 2, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37930432

RESUMEN

Current lithium-ion batteries (LIBs) rely on organic liquid electrolytes that pose significant risks due to their flammability and toxicity. The potential for environmental pollution and explosions resulting from battery damage or fracture is a critical concern. Water-based (aqueous) electrolytes have been receiving attention as an alternative to organic electrolytes. However, a narrow electrochemical-stability window, water decomposition, and the consequent low battery operating voltage and energy density hinder the practical use of aqueous electrolytes. Therefore, developing novel aqueous electrolytes for sustainable, safe, high-performance LIBs remains challenging. This Review first commences by summarizing the roles and requirements of electrolytes-separators and then delineates the progression of aqueous electrolytes for LIBs, encompassing aqueous liquid and gel electrolyte development trends along with detailed principles of the electrolytes. These aqueous electrolytes are progressed based on strategies using superconcentrated salts, concentrated diluents, polymer additives, polymer networks, and artificial passivation layers, which are used for suppressing water decomposition and widening the electrochemical stability window of water of the electrolytes. In addition, this Review discusses potential strategies for the implementation of aqueous Li-metal batteries with improved electrolyte-electrode interfaces. A comprehensive understanding of each strategy in the aqueous system will assist in the design of an aqueous electrolyte and the development of sustainable and safe high-performance batteries.

14.
Biodivers Data J ; 11: e110948, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37859644

RESUMEN

Background: The genus Froggattiella Leonardi, 1900 belongs to the family Diaspididae, and five species of Froggattiella have been recorded worldwide. In this study, Froggattiellapenicillata (Green, 1905), which attacks bamboos, is newly recorded in South Korea. The colonies of F.penicillata were collected on a bamboo forest located in Gajwa-dong, Jinju-si, Gyeongsangnam-do, South Korea (35.1599, 128.1029). Description of the adult female, host plant, adult female illustrations, and global distribution of this species are provided. New information: Froggattiellapenicillata (Green, 1905) is reported for the first time in South Korea. This species occurrs under sheathing bases of the leaves and is observed attached on the stem and not on the leaf.

15.
Materials (Basel) ; 16(16)2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37630000

RESUMEN

The effect of tempering temperature on the hydrogen embrittlement characteristics of SCM440 tempered martensitic steels was investigated in terms of their microstructure and hydrogen desorption behavior. The microstructures were characterized using scanning and transmission electron microscopy, as well as X-ray diffraction and electron backscattered diffraction analysis. Thermal desorption analysis (TDA) was performed to examine the amount and trapping behavior of hydrogen. The cementite morphology of the SCM440 tempered martensitic steels gradually changed from a long lamellar shape to a segmented short-rod shape with an increasing tempering temperature. A slow strain rate tensile test was conducted after electrochemical hydrogen charging to evaluate the hydrogen embrittlement resistance. The hydrogen embrittlement resistance of the SCM440 tempered martensitic steels increased with an increasing tempering temperature because of the decrease in the fraction of the low-angle grain boundaries and dislocation density. The low-angle grain boundaries and dislocations, which acted as reversible hydrogen trap sites, were critical factors in determining the hydrogen embrittlement resistance, and this was supported by the decreased diffusible hydrogen content as measured by TDA. Fine carbides formed in the steel tempered at a relatively higher temperature acted as irreversible hydrogen trap sites and contributed to improving the hydrogen embrittlement resistance. Our findings can suggest that the tempering temperature of SCM440 tempered martensitic steel plays an important role in determining its hydrogen embrittlement resistance.

16.
Polymers (Basel) ; 15(13)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37447442

RESUMEN

This study aims to analyze tire wear particulate matter (TWP) from tread rubber with different formulations and to compare the concentration of TWP with different wear devices. The TWP generated during the abrasion of truck and bus radial (TBR) tires were examined, and the effect of using different types of rubber and carbon black (CB) were investigated. When natural rubber (NR) was solely used as the tire tread rubber material, there was a higher concentration of 5-10 µm TWP. However, when the tread formulation consisted of NR mixed with butadiene rubber, the TWP concentration decreased. Changing the type of CB also reduced the amount of TWP in the 2.5 µm size range. The TWP concentration in the specimens increased with increasing speed and vertical load. The TWP generated during the abrasion tests using wear testers and tire simulators exhibited similar trends. These findings suggest that modifying tire tread formulations can effectively control the distribution and amount of TWP generation.

17.
Macromol Biosci ; 23(11): e2300221, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37365122

RESUMEN

Type 2 Diabetes Mellitus (T2D) is a chronic, obesity-related, and inflammatory disorder characterize by insulin resistance, inadequate insulin secretion, hyperglycemia, and excessive glucagon secretion. Exendin-4 (EX), a clinically established antidiabetic medication that acts as a glucagon-like peptide-1 receptor agonist, is effective in lowering glucose levels and stimulating insulin secretion while significantly reducing hunger. However, the requirement for multiple daily injections due to EX's short half-life is a significant limitation in its clinical application, leading to high treatment costs and patient inconvenience. To address this issue, an injectable hydrogel system is developed that can provide sustained EX release at the injection site, reducing the need for daily injections. In this study, the electrospray technique is examine to form EX@CS nanospheres by electrostatic interaction between cationic chitosan (CS) and negatively charged EX. These nanospheres are uniformly dispersed in a pH-temperature responsive pentablock copolymer, which forms micelles and undergoes sol-to-gel transition at physiological conditions. Following injection, the hydrogel gradually degraded, exhibiting excellent biocompatibility. The EX@CS nanospheres are subsequently released, maintaining therapeutic levels for over 72 h compared to free EX solution. The findings demonstrate that the pH-temperature responsive hydrogel system containing EX@CS nanospheres can be a promising platform for the treatment of T2D.


Asunto(s)
Quitosano , Diabetes Mellitus Tipo 2 , Nanosferas , Humanos , Exenatida/farmacología , Exenatida/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hidrogeles/farmacología , Hidrogeles/uso terapéutico , Quitosano/farmacología , Quitosano/uso terapéutico , Temperatura , Concentración de Iones de Hidrógeno
18.
Materials (Basel) ; 16(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36676522

RESUMEN

Synthetic tough hydrogels have received attention because they could mimic the mechanical properties of natural hydrogels, such as muscle, ligament, tendon, and cartilage. Many recent studies suggest various approaches to enhance the mechanical properties of tough hydrogels. However, directly comparing each hydrogel property in different reports is challenging because various testing specimen shapes/sizes were employed, affecting the experimental mechanical property values. This study demonstrates how the specimen geometry-the lengths and width of the reduced section-of a tough double-network hydrogel causes differences in experimental tensile mechanical values. In particular, the elastic modulus was systemically compared using eleven specimens of different shapes and sizes that were tensile tested, including a rectangle, ASTM D412-C and D412-D, JIS K6251-7, and seven customized dumbbell shapes with various lengths and widths of the reduced section. Unlike the rectangular specimen, which showed an inconsistent measurement of mechanical properties due to a local load concentration near the grip, dumbbell-shaped specimens exhibited a stable fracture at the reduced section. The dumbbell-shaped specimen with a shorter gauge length resulted in a smaller elastic modulus. Moreover, a relationship between the specimen dimension and measured elastic modulus value was derived, which allowed for the prediction of the experimental elastic modulus of dumbbell-shaped tough hydrogels with different dimensions. This study conveys a message that reminds the apparent experimental dependence of specimen geometry on the stress-strain measurement and the need to standardize the measurement of of numerous tough hydrogels for a fair comparison.

19.
Adv Mater ; 35(3): e2206207, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36314423

RESUMEN

Tendon consists of soft collagen, yet it is mechanically strong and firmly adhered to the bone owing to its hierarchically anisotropic structure and unique tendon-to-bone integration (enthesis), respectively. Despite the recent advances in biomaterials, hydrogels simultaneously providing tendon-like high mechanical properties and strong adhesion to bone-mimicking enthesis is still challenging. Here, a strong, stiff, and adhesive triple-network (TN) anisotropic hydrogel that mimics a bone-adhering tendon is shown. The tough adhesive TN hydrogel is developed by combining imidazole-containing polyaspartamide (providing multiple hydrogen bonds to the bone surface) and energy-dissipative alginate-polyacrylamide double-network. To mimic the anisotropic structure and high mechanical properties of tendons, the bone-adhered TN hydrogel is linearly stretched and subsequently fixed via secondary cross-linking. The resulting hydrogel exhibits high tensile modulus and strength while maintaining a high bone adhesion without chemical modification of the bone surface. Furthermore, a bone-ligament-bone structure with strong bone adhesion reminiscent of the natural ligament is realized.


Asunto(s)
Adhesivos , Hidrogeles , Hidrogeles/química , Huesos , Tendones , Materiales Biocompatibles
20.
Int J Mol Sci ; 25(1)2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38203337

RESUMEN

Psoriasis is a chronic inflammatory skin disease characterized by epidermal hyperproliferation, aberrant differentiation of keratinocytes, and dysregulated immune responses. WW domain-containing oxidoreductase (WWOX) is a non-classical tumor suppressor gene that regulates multiple cellular processes, including proliferation, apoptosis, and migration. This study aimed to explore the possible role of WWOX in the pathogenesis of psoriasis. Immunohistochemical analysis showed that the expression of WWOX was increased in epidermal keratinocytes of both human psoriatic lesions and imiquimod-induced mice psoriatic model. Immortalized human epidermal keratinocytes were transduced with a recombinant adenovirus expressing microRNA specific for WWOX to downregulate its expression. Inflammatory responses were detected using Western blotting, real-time quantitative reverse transcription polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay. In human epidermal keratinocytes, WWOX knockdown reduced nuclear factor-kappa B signaling and levels of proinflammatory cytokines induced by polyinosinic: polycytidylic acid [(poly(I:C)] in vitro. Furthermore, calcium chelator and protein kinase C (PKC) inhibitors significantly reduced poly(I:C)-induced inflammatory reactions. WWOX plays a role in the inflammatory reaction of epidermal keratinocytes by regulating calcium and PKC signaling. Targeting WWOX could be a novel therapeutic approach for psoriasis in the future.


Asunto(s)
Dermatitis , Psoriasis , Animales , Humanos , Ratones , Modelos Animales de Enfermedad , Inflamación , FN-kappa B , Psoriasis/inducido químicamente , Psoriasis/genética , Proteínas Supresoras de Tumor/genética , Oxidorreductasa que Contiene Dominios WW/genética
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