Tissue Adhesives Research Articles

Abstract A042: Desmosome mutations in the microenvironment regulate melanoma proliferation

Abstract Desmosomes are transmembrane protein complexes critical for cell-cell adhesion in epithelial tissues and other cell types. In skin cancers like melanoma, epithelial cells called keratinocytes are the predominant cells in the primary melanoma microenvironment, yet it remains largely unknown whether this cell type is subject to genetic alterations during melanoma development and its role in early melanoma progression. In this study, using an integrative analysis of tumor mutations and protein biophysical interactions, we identify a high frequency of genetic alterations in desmosome-related genes in human cancers, with the highest occurrences in cutaneous melanoma. Notably, over 70% of cutaneous melanoma cases exhibit mutations in desmosome genes and desmosome gene mutations are associated with lowered expression of the desmosome complex in melanoma. Using spatial transcriptomics and immunohistochemistry analyses, we find that the decrease in desmosome gene expression predominantly occurs in keratinocytes within the tumor microenvironment rather than in the melanoma cells themselves. To study the functional significance of this alteration in melanoma development, we used a human melanoma/keratinocyte co-culture system using primary melanoma cell lines. Our studies show that knockdown of desmosome genes in keratinocytes markedly increased proliferation of adjacent melanoma cells in melanoma/keratinocyte co-cultures. Additionally, melanoma cell proliferation is enhanced when exposed to media preconditioned by desmosome-deficient keratinocytes. These observations suggest that the gradual accumulation of mutations in desmosome genes within neighboring keratinocytes may create a conducive environment that primes melanoma cells for neoplastic transformation. This study underscores the critical role of genetic alterations in the tumor microenvironment in melanoma progression and highlights the potential for targeting desmosome-related pathways in therapeutic strategies against melanoma. Citation Format: Mohita Tagore. Desmosome mutations in the microenvironment regulate melanoma proliferation [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr A042.

Endoscopic revision surgery for ossicular chain reconstruction: intraoperative findings and functional outcomes.

To report the intraoperative observations and hearing outcomes in patients undergoing endoscopic revision ossiculoplasty. A retrospective cohort of patients who had undergone revision ossiculoplasty were enrolled in this study. Intraoperative findings were documented. Follow-up visits were scheduled from 3 to 12 months post-surgery to assess hearing levels and record any potential complications. Between April 2020 and May 2023, a total of 26 cases were enrolled, with 11 male patients represented. The mean age of the patients was 40.5 ± 9.4 years, ranging from 18 to 66 years. During the revision surgeries, various intraoperative findings were noted, including adhesive tissues affecting the activity of ossicular chain (observed in 37.0% of cases), tympanosclerosis of the ossicular chain (also in 37.0% of cases), dislocation of ossicular prosthesis (33.3%), erosion of the ossicular chain (33.3%), and identified cholesteatoma (11.1%). In terms of hearing outcomes, a significant improvement was observed. Overall, only 37.0% of patients achieved an air-bone gap of 20 dB or less, indicating the inferior outcome in revision ossiculoplasty. This study highlight the role of inflammatory responses (adhesion, tympanosclerosis), stapes erosion, and prosthesis dislocation, as contributing factors to the failure of primary tympanoplasty. Endoscopic revision ossiculoplasty emerges as a reliable and effective approach.

Self-Healing, Electrically Conductive, Antibacterial, and Adhesive Eutectogel Containing Polymerizable Deep Eutectic Solvent for Human Motion Sensing and Wound Healing.

Flexible electronic devices such as wearable sensors are essential to advance human-machine interactions. Conductive eutectogels are promising for wearable sensors, despite their challenges in self-healing and adhesion properties. This study introduces a multifunctional eutectogel based on a novel polymerizable deep eutectic solvent (PDES) prepared by the incorporation of diallyldimethylammonium chloride (DADMAC) and glycerol in the presence of polycyclodextrin (PCD)/dopamine-grafted gelatin (Gel-DOP)/oxidized sodium alginate (OSA). The synthesized eutectogel has reversible Schiff-base bonds, hydrogen bonds, and host-guest interactions, which enable rapid self-healing upon network disruption. GPDO-15 eutectogel has significant tissue adhesion, high stretchability (419%), good ionic conductivity (0.79 mS·cm-1), and favorable antibacterial and self-healing properties. These eutectogels achieve 90% antibacterial effect, show excellent biocompatibility, and can be used as sensors to monitor human activities with strong stability and durability. The in vivo studies indicate that the eutectogels can improve the wound healing process which makes them an effective option for biological dressings.

Injectable Polydopamine Nanoparticle-Incorporated Hydrogels for Antiangiogenesis and Stimulating Tumoricidal Immunity to Inhibit Metastasis and Recurrence Postresection.

Surgical resection is still the main means for clinical treatments of breast cancer, but the postoperative immunosuppressive microenvironment and neoangiogenesis of the residual tumors easily lead to tumor metastasis and recurrence, which will further endanger patients' lives. The combination of antiangiogenic therapy and immunotherapy may promote the mutually reinforced cycle of immune reprogramming and vascular normalization to avoid tumor metastasis and recurrence. Herein, we prepared polydopamine nanoparticles for improving tissue adhesion and enriching tumor-associated antigens. This nanoregulator together with regorafenib (REG) was further incorporated into a hydrogel developed from grafting adipic acid dihydrazide onto 2,2,6,6-tetramethylpiperidine-1-oxyl radical oxidized chitin and oxidized hyaluronic acid, which was injectable at the cavity after subcutaneous tumor surgery with good mechanical properties and degradability. The system showed long-term release of REG. After combining with anti-PD-L1, the hydrogel applied to the surgical wound exhibited a reduction in tumor metastasis and recurrence. This effect was achieved by suppressing angiogenesis and enhancing antitumor immunity, characterized by increased levels of effector T lymphocytes and activation of dendritic cells within tumors, spleens, and draining lymph nodes. The injectable hydrogel offers a promising strategy for postoperative management aimed at preventing tumor metastasis and recurrence.

Cysteine Conjugation: An Approach to Obtain Polymers with Enhanced Muco- and Tissue Adhesion

The modification of polymers towards increasing their biocompatibility gathers the attention of scientists worldwide. Several strategies are used in this field, among which chemical post-polymerization modification has recently been the most explored. Particular attention revolves around polymer-L-cysteine (Cys) conjugates. Cys, a natural amino acid, contains reactive thiol, amine, and carboxyl moieties, allowing hydrogen bond formation and improved tissue adhesion when conjugated to polymers. Conjugation of Cys and its derivatives to polymers has been examined mostly for hyaluronic acid, chitosan, alginate, polyesters, polyurethanes, poly(ethylene glycol), poly(acrylic acid), polycarbophil, and carboxymethyl cellulose. It was shown that the conjugation of Cys and its derivatives to polymers significantly increased their tissue adhesion, particularly mucoadhesion, stability at physiological pH, drug encapsulation efficiency, drug release, and drug permeation. Conjugates were also non-toxic toward various cell lines. These properties make Cys conjugation a promising strategy for advancing polymer applications in drug delivery systems and tissue engineering. This review aims to provide an overview of these features and to present the conjugation of Cys and its derivatives as a modern and promising approach for enhancing polymer tissue adhesion and its application in the medical field.

In Situ Forming Injectable Gelatin-Based Antibacterial Bioadhesives for Preventing Postoperative Leakage and Abdominal Adhesions.

Postoperative anastomotic leakage (AL) and abdominal adhesions are two major complications after intestinal surgery, with an incidence of 2-25% for AL and 93% for adhesion. Until now, there is no method addressing AL and abdominal adhesions simultaneously. In this work, Bi-PEG-succinimidyl succinate (PEG-NHS), amino-gelatin (Agel) is combined with cefoperazone-sulbactam (SCF) to prepare a multifunctional bioadhesive (SCF/SEAgel) for the postoperative leakage and adhesion prevention. SCF/SEAgel possesses a great sealing capability for tissue, with a bursting pressure of 54kPa. The loaded SCF endows the systems with good antibacterial properties. The in vivo antiadhesion experiments show that SCF/SEAgel possesses better anti-adhesion properties than the commercially used sodium hyaluronate gel. In the cecum leakage model, the SCF/SEAgel effectively seals the leakage with a survival rate of 100%, superior to commercial products (Sainaoning). Meanwhile, it significantly reduces tissue adhesion. Finally, the laparoscopic surgery with dogs shows that the SCF/SEAgel can be injected through minimally invasive surgery, demonstrating its ease of use. Combined with its great biocompatibility, SCF/SEAgel is very promising in intestinal surgery.

Rapid, Controlled Branching Polymerization of Cyanoacrylate via Pathway-Enabled, Site-Specific Branching Initiation.

Controlled branched structures remain a key synthetic limitation for monomeric tissue adhesives because their on-site polymerization that enables adhesion formation requires rapid kinetics, high conversion, and straightforward setup. In this context, site-specific branching initiation by using evolmers is potentially effective for structural control; however, the efficiency and kinetics in current reaction setups persists to be a major challenge. In this paper, an evolmer induces a controlled branching polymerization of cyanoacrylate amid the high monomer reactivity useful in rapid adhesion. The contrasting reactivities between the vinyl and the initiating groups in the evolmer molecule generate a kinetic pathway that favors a control-enabling branching mechanism. Through density functional theory calculations, the reaction pathway toward branching is shown to kinetically favor site-specific initiation by six orders of magnitude than the route toward non-specificity. Reaction monitoring confirms the branching polymerization after the polymerization with the evolmer forms a more compact structure than the linear counterpart. Control of branching density is demonstrated in rapid polymerizations within minutes and in polymerizations completed in an instant. These results provide a template for achieving site-specific branching initiation during adhesion formation and, broadly, where conditions for kinetic control are necessary.

In Situ Forming Supramolecular Nanofiber Hydrogel as a Biodegradable Liquid Embolic Agent for Postembolization Tissue Remodeling.

Embolic agents have been widely used to treat blood vessel abnormalities in interventional radiology as a minimally invasive procedure. However, only a few biodegradable liquid embolic agents exhibit high embolization performance, biodegradability, and operability. Herein, the design of in situ-forming supramolecular nanofiber (SNF) hydrogels is reported as biodegradable liquid embolic agents with the assistance of Bayesian optimization through an active learning pipeline. Chemically modified gelatin with hydrogen-bonding moieties produces fibrin-inspired nanofiber-based hydrogels with a high blood coagulation capacity. The low viscosity of the SNF hydrogels makes them injectable using a microcatheter, and the hydrogel shows sufficient tissue adhesion to the blood vessel walls and very weak adhesion to the catheter tubes. Moreover, the SNF hydrogels exhibit high blood compatibility, cytocompatibility, cell-adhesive properties, and biodegradability (in vitro and in vivo). Intravascularly delivered SNF hydrogels induce embolization of rat femoral arteries. This biodegradable liquid embolic agent could be a powerful tool for interventional radiology in the treatment of various diseases, including aortic aneurysm stent grafting, gynecological diseases, and liver cancer.

A Dry Patch with In Situ Solid-to-Gel Transformation for All-in-One Skin Wound Care.

Hydrogel-based dressing materials offer significant potential in expediting skin wound healing. Nevertheless, they face several challenges: poor adhesion to wound tissues, difficulties in preservation under ambient conditions, and limited multifunctionality to support all wound healing stages. In this work, a dry patch is designed to address these persistent issues by featuring an in situ solid-to-gel transformation and Janus wet tissue adhesiveness. The HGP patch integrates a wet adhesive layer combining dopamine-conjugated hyaluronic acid (HD) and poly(acrylic acid) (PAA), a drug-loading layer comprising gelatin (Gel), and a nonadhesive gelation layer of poly(vinyl alcohol) (PVA) and sodium alginate (SA). This hierarchical structural design confers exceptional wound adhesion, hemostatic capabilities, and antibacterial and antioxidant activities, as well as immune regulatory properties. These attributes collectively support accelerated skin wound healing, particularly in cases complicated by bacterial infections. This research charts an approach to engineer hydrogel-based wound dressings through on-site hydrogel formation, thus advancing the treatment of wounds afflicted with complex infections.

Metatarsal sliding osteotomy is effective without altering plantar pressure in Morton's neuroma: Retrospective case series.

Various operative methods for the treatment of Morton's neuroma have been discussed, and osteotomy of the metatarsal bone has been reported recently. However, there has been no report of pedobarographic changes after metatarsal osteotomy. Pedobarographic changes of other metatarsal area after the surgery may cause transfer metatarsalgia, and thorough analysis of the pedobarographic data should be performed peri-operatively. The purpose of this study is to investigate the post-operative pedobarographic changes of sliding osteotomy of the 3rd metatarsal bone for treating Morton's neuroma. Forty patients (45 feet) who underwent metatarsal sliding osteotomy of the 3rd metatarsal bone for treating Morton's neuroma from November 2013 to December 2021 were retrospectively reviewed. Proximal sliding osteotomy was performed at the proximal 3rd metatarsal bone through dorsal approach. Clinical outcomes were evaluated with American Orthopaedic Foot and Ankle Society Lesser Metatarsophalangeal Interphalangeal Scale (AOFAS LMIS), Foot Function Index (FFI), and Visual Analogue Scale (VAS). Plain radiograph and pedobarogram were performed to evaluate the radiologic and pedobarographic outcomes. AOFAS score was improved from 52.8±9.0 (18-62) to 88.8±9.8 (78-100) and FFI was improved from 61.8±4.9 (50-70) to 32.2±5.1 (23-42) on average. The 3rd metatarsal bone was shortened by 3.1±0.8mm and dorsally shifted by 1.5±0.4mm after the surgery. Plantar intermetatarsal distances between 2nd and 3rd and 3rd and 4th metatarsal heads were significantly increased post-operatively. Average forefoot pressure and maximum pressure of the 2nd to 4th metatarsal head were not significantly changed between pre-operatively and post-operatively. Proximal metatarsal sliding osteotomy of the 3rd metatarsal bone shows a satisfactory result in both clinical and pedobarographical evaluations. It could be an effective treatment of permanent indirect decompression of Morton's neuroma with avoiding recurred neuroma, adhesion of tissue, paresthesia, and transfer metatarsalgia.

Rapidly in situ forming antibiotic-free injectable hydrogel wound dressing for eradicating drug-resistant bacterial infections in human skin organoids

The rising prevalence of global antibiotic resistance evokes the urgent requirement to explore the alternative antimicrobial candidates. It is of great significance to overcome these serious threats of multidrug-resistant bacterial infections and difficult-to-heal cutaneous wounds to human health. Herein, we proposed a rapidly in situ forming innovative antibiotic-free hydrogel dressing with excellent biocompatibility, easy injectability, strong tissue adhesion and superior antibacterial activity against drug-resistant bacteria. An octa-armed poly(ethylene glycol) amine (Octa-PEG-NH2) was quickly crosslinked with a green industrial microbicide tetrakis (hydroxymethyl) phosphonium chloride (THPC) to form an antibacterial hydrogel (OPTH) by simple mixing without any other initiators or crosslinkers. A significant broad-spectrum antibacterial efficacy was demonstrated against Gram-positive Staphylococcus aureus (S. aureus), Gram-negative Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA). Significantly, benefiting from its flexible injectability and reliable tissue adhesion, the excellent antibacterial performances were further evidenced by employing human-induced pluripotent stem cell (iPSC)-derived skin organoids in a 3D culture system and rat animal wound models in vivo with MRSA infection, thus allowing for reepithelization promotion and wound healing. Collectively, the findings not only propose a facile gelatinization strategy for readily accessible antibiotic-free hydrogel dressings for effective MRSA therapy but also hold great clinical translation potential in obliterating multi-pathogenic bacteria and accelerating wound healing.

Enhanced Purification of Uterine Smooth Muscle Cells from Adenomyosis Using a Novel Dual- Enzyme Digestion Method

Uterine adenomyosis causing attention to the abnormal smooth muscle layer has recently received increasing attention, which has created the need for a method that can efficiently collect high purity uterine smooth muscle cells (USMC) in a laboratory setting. In this study, we explored the composition ratios of the digestion solution to obtain the optimal digestion solution (DM4). Furthermore, we tested the superiority of the two methods of obtaining adenomyotic uterine smooth muscle by comparing DM4 with the conventional tissue adhesion method by growth rate, single-cell RNA sequencing, and purity of fluorescence identification. The results demonstrated that USMCs produced by the DM4 digestion method exhibited significantly higher rates of proliferation and were more effective in generating mature smooth muscle cells of high purity compared to those obtained using tissue adherence methods, which is more inclined to isolate the progenitor cell population. This study presents a reliable method for isolating USMCs and provides a solid foundation for future studies on the etiology and mechanism of adenomyosis.

Antibacterial chitosan/organic rectorite nanocomposite-conjugated gelatin/β-cyclodextrin hydrogels with improved hemostasis performance for wound repair

Bacterial infections and severe bleeding continue to pose significant challenges in wound repair. There is an urgent need for innovative, nature-inspired hydrogel dressings with antibacterial and hemostatic properties. A Ge-β-CD-CS-OREC conjugate hydrogel was developed by grafting β-CD and CS-OREC nanocomposites into a Ge matrix using EDC/NHS crosslinking, as confirmed by FT-IR and EDX analyses. Compared to single Ge-β-CD cross-linked hydrogels, the addition of CS-OREC enhanced the hydrogel's properties, including increased pore size (60 ± 14 μm), improved wettability (WCA = 28.82 ± 0.6°), enhanced tensile strength (41.3 ± 3.56 KPa), and strong tissue adhesion. Furthermore, this hydrogel demonstrated excellent cytocompatibility when co-cultured with keratinocytes (Kcs) and vascular endothelial cells (VECs). The incorporation of CS chains into OREC interlayers allowed the hydrogel to specifically target bacteria and increase membrane permeability in Pseudomonas aeruginosa (PA), Klebsiella pneumoniae (KP), and Staphylococcus aureus (SA), effectively reducing the bacterial load in infected wounds by 50.24–73.92 % compared to controls in vivo. Further, the hydrogel exhibited superior hemostatic efficiency (78 ± 10 s) over commercial gauze and other gels by enhancing platelet activation and coagulation factor secretion. The hydrogel accelerated tissue regeneration by promoting epithelial maturation and blood vessel regeneration, indicating its clinical potential as promising wound dressing.

Rapid preparation of bioadhesive hydrogels containing catechol moieties at room temperature with reproducible adhesion to wet tissues, antimicrobial, antioxidant capacity for noncompressive hemostasis.

In order to cope with the massive tissue bleeding caused by sudden trauma and the demand for bioengineering materials with adjustable wet adhesion properties, this study formed the first layer of network by adding galactomannan (GG) and collagen (Col) structure, and then use the Fe3+-urushiol (UH) redox system to activate free radicals to initiate the polymerization of acrylic acid (AA) to quickly form an interpenetrating double network hydrogel. The cis hydroxyl group in GG and the hydroxyl group of UH form dynamic covalent borate ester bonds with borate ions in the borax solution, and use their responsiveness to pH to control the catechol group to achieve controllable adhesion. UH and Fe3+ endowed the hydrogel with excellent antibacterial ability, while adding Col enhanced the mechanical properties of the hydrogel. The elastic modulus and toughness increased from 4.32 kPa and 92.9 kJ/m3 to 18.90 kPa and 264.54 kJ/m3. In addition, due to the joint action of UH and Col, the hydrogel dressing can achieve rapid hemostasis within 20 s. In short, this hydrogel dressing has good biocompatibility, inherent antibacterial ability, adjustable moist tissue adhesion properties and rapid hemostatic ability, and is expected to become a candidate for wound hemostasis dressing.

Antioxidant hydrogel from poly(aspartic acid) and carboxymethylcellulose with quercetin loading as burn wound dressing

Susceptibility to infection and excessive accumulation of reactive oxygen species (ROS) are the greatest obstacles for burn wound healing. In this research, the 5-aminosalicylic acid (ASA) grafted poly(aspartic hydrazide) (PASH) was synthesized by successive ploysuccinimide (PSI) ring opening reaction and reacted with oxidized carboxymethyl cellulose (DCMC) to fabricate biodegradable hydrogel through Schiff-base cross-linking. Moreover, the hydrogel was loaded with quercetin (QT) to enhance its anti-inflammatory performance. The ASA moiety endowed the hydrogel with the free radical scavenging ability and mussel inspired tissue adhesion to maintain the healing bioenvironment of the wound. The loading of QT gave the hydrogel more phenolic hydroxy group and further enhanced the antioxidant capacity of the hydrogel. The in vitro experiment revealed the grafted ASA moiety and the loaded QT greatly enhanced the ROS elimination property and antibacterial property. Moreover, the QT loaded hydrogel accelerated the burn wound repairing rate in the in vivo mice model. Based on above result, the PASH/DCMC could act as a new platform for QT loading to promote the burn wound repairing.

High Antimicrobial Electrotherapy and Wound Monitoring Hydrogel with Bimetal Phenolic Networks for Smart Healthcare

AbstractThe design and fabrication of novel soft bioelectronic materials for rapid wound healing and real‐time monitoring are critical for smart healthcare. However, developing such integrated multifunctional materials devices remains challenging due to fabrication dynamics and sensing interface issues. Herein, a novel strategy is presented for accelerating the kinetics of hydrogels integrating antimicrobial, electrotherapeutic, and wound monitoring functions via bimetallic phenolic networks. The Al3+ catalyzes the radical copolymerization reaction of acrylic acid, resulting in the gelation of the system within 10 s, and also catalyzes the redox reaction between silver and lignin, inducing the sustained release of catechol, which significantly enhances the hydrogel's antimicrobial activity and shortened the wound healing process. Meanwhile, the abundant non‐covalent interactions enhance the hydrogel's tissue adhesion, and mechanical properties (tensile strength 1.558 MPa and elongation 1563%). In addition, the bimetallic ions endow the hydrogels with excellent sensing properties. Under the synergy of electrical stimulation, the wound healing rate is accelerated. Notably, wound assessment can be performed by monitoring changes in electrical signals over the wound, which can assist physicians and patients in achieving intelligent wound management. This work provides new insights into the design and application of multifunctional smart bioelectronic materials.

OS IMPACTOS DO TAPING NO PÓS-OPERATORIO EM ABDOMINOPLASTIA E LIPOASPIRAÇÃO: REVISÃO INTEGRATIVA

With a progressive increase in the number of plastic surgeries, the role of physiotherapy has been evolving exponentially. With this, it highlights the importance of using specific procedures in the postoperative period in order to reduce possible complications and reactions from surgery such as edema, seroma, fibrosis, hematoma, pain, scarring and tissue adhesions. The main objective of physiotherapeutic treatment in the preoperative period of plastic surgery is to avoid or reduce complications such as the incidence of scars, adhesions, edema, hematomas and pulmonary complications. The present study is an integrative literature review, carried out through an electronic search of the Medical Literature Analysis System (PudMed) Scientific Electronic Library Online (Scielo) database. This study can conclude with this study that the use of lymphatic taping in the postoperative period of abdominoplasty and liposuction is effective in reducing edema, preventing bruising and reducing the patient's pain, due to its action on the lymphatic system, thus having fewer complications. and complications.

The Toll-like receptor 4 antagonist TAK-242 in combination with sodium hyaluronate alleviates postoperative abdominal adhesion in a mouse model

Postoperative abdominal adhesion is one of the most common complications after abdominal surgery. The Toll-like receptor 4 (TLR4) signaling pathway is one of the most common inflammation-related pathways, and it has been demonstrated that TLR4 is highly expressed in adhesive tissues; however, the function of TLR4 in adhesion formation has not yet been studied. In the present study, the expression of TLR4 was first detected by immunohistochemical (IHC) and double-immunofluorescence staining in 40 mice, which were randomly divided into four groups, and sacrificed at 1, 3, 5 and 7 days after surgery. Subsequently, another 40 mice were randomly divided into five groups; with the exception of the sham group, the other groups were modeled and treated with saline that contained DMSO, sodium hyaluronate (HA), TAK-242 or TAK-242 + HA (applied to damaged peritoneal wounds). A total of 7 days after surgery, the mice were sacrificed and specimens were collected. Inflammation was detected by hematoxylin and eosin staining, and ELISA of transforming growth factor- β1 (TGF-β1) and interleukin-6 (IL-6); collagen deposition was examined by Masson staining and IHC staining of α-SMA; and reactive oxygen species (ROS) were detected by ROS staining and malondialdehyde (MDA) assay. The results revealed that TLR4 was highly expressed in the adhesive tissues at 3, 5 and 7 days after surgery. In addition, TAK-242 + HA treatment could reduce abdominal adhesion formation, exhibiting lower Nair’s score and inflammation scores, lower TGF-β1 and IL-6 levels, and lower collagen thickness and α-SMA levels compared with those in the control group. In addition, the TAK-242 + HA group had lower levels of ROS and MDA compared with those in the control group. The present study revealed that TLR4 was highly expressed in the process of adhesion formation and its inhibitor, TAK-242, combined with HA, could reduce adhesion formation by reducing inflammation and ROS, and alleviating collagen deposition.

Immunomodulatory hydrogel patches loaded with curcumin and tannic acid assembled nanoparticles for radiation dermatitis repair and radioprotection

Radiation dermatitis, as a major side effect of radiotherapy, is a form of skin injury linked to the production of reactive oxygen species (ROS). Development of functional patches with excellent ROS scavenging ability and biosafety is crucial for radioactive dermatitis repair. Herein, we present a nanohybrid hydrogel patch composed with natural-derived substances. The patch possesses dual functionalities of chemically scavenging ROS and physically absorbing radiation, thereby alleviating radiation damage. Curcumin@tannic acid (Cur@TA) nanoparticles are synthesized through spontaneous coordination of TA and iron ions (Fe3+), enabling the encapsulation of Cur. The nanoparticles are then loaded into gelatin methacryloyl (GelMA) hydrogel patches, which endow the hydrogel with tissue adhesion as well as photothermal properties. Simultaneously, the patch exhibits powerful ROS scavenging capability and promotes M2 polarization of macrophages. Additionally, the high-water content of the GelMA hydrogel enables physical absorption of low-energy X-rays, providing radiation shielding. Based on these characteristics, we have demonstrated the augmented therapeutic efficacy of the hydrogel patch loaded with Cur@TA nanoparticles in the mouse model of radiation dermatitis. Our findings introduce a novel therapeutic approach for radiation protection and treatment, with potential clinical applications.

Hybrid Hydrogels of Polyacrylamide and Self-assembly Photodynamic Nanoparticles with Diverse Adhesion for Infected Chronic Wound Healing.

The healing of infected wounds is challenging for patients. In this paper, a hybrid hydrogel with strong tissue adhesion, self-healing, and antibiosis without antibiotics was developed as a dressing to promote the healing of infected chronic wounds. Acrylamide (PAM) was polymerized with N,N-methylene bis(acrylamide) (BIS) as the substrate, and self-assembled nanoparticles of carboxymethyl chitosan and chlorin e6 (CMCS/Ce6 NPs) trapped with magnesium (Mg2+) ions were dispersed in the hydrogel substrate. CMCS/Ce6 NPs provided favorable photodynamic antibiosis via the production of reactive oxygen species (ROS) under NIR irradiation. The hybrid hydrogels exhibited excellent self-healing properties, diverse adhesion, and biocompatibility. The in vivo results indicated that the hybrid hydrogel accelerated wound healing significantly via comprehensive factors of photodynamic antibiosis of CMCS/Ce6 NPs, cell proliferation promotion by Mg2+, good bioadhesion, and moisture retention of the PAM hydrogel, which promoted collagen deposition and blood vessel maturation.