Tissue Adhesives Research Articles

Ionically assembled hemostatic powders with rapid self-gelation, strong acid resistance, and on-demand removability for upper gastrointestinal bleeding.

Upper gastrointestinal bleeding (UGIB) is bleeding in the upper part of the gastrointestinal tract with an acidic and dynamic environment that limits the application of conventional hemostatic materials. This study focuses on the development of N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride/phytic acid (HTCC/PA, HP) powders with fast hemostatic capability and strong acid resistance, for potential applications in managing UGIB. Upon contact with liquids within 5 seconds, HP powders rapidly transform into hydrogels, forming ionic networks through electrostatic interactions. The ionic crosslinking process facilitates the HP powders with high blood absorption (3.4 times of self-weight), sufficient tissue adhesion (5.2 and 6.1 kPa on porcine skin and stomach, respectively), and hemostasis (within 15 seconds for in vitro clotting). Interestingly, the PA imparts the HP powders with strong acid resistance (69.8% mass remaining after 10 days of incubation at pH 1) and on-demand removable sealing while HTCC contributes to fast hemostasis and good wet adhesion. Moreover, the HP powders show good biocompatibility and promote wound healing. Therefore, these characteristics highlight the promising clinical potential of HP powders for effectively managing UGIB.

A MnO2 nanosheets doping double crosslinked hydrogel for cartilage defect repair through alleviating inflammation and guiding chondrogenic differentiation

The inflammatory microenvironment and inferior chondrogenesis are major symptoms after cartilage defect. Although various modifications strategies associated with hydrogels exhibit remarkable capacity of pro-cartilage regeneration, the adverse effect by prolonging inflammation is still formidable to hamper potential biomedical applications of different hydrogel implants. Herein, inspired by the repair microenvironment of articular cartilage defects, an injectable, immunomodulatory, and chondrogenic L-MNS-CMDA hydrogel is prepared through grafting vinyl and catechol groups to chitosan macromolecules using amide reaction, then further loading MnO2 nanosheets (MNS). The double crosslinking of photopolymerization and catechol oxidative polymerization endows L-MNS-CMDA hydrogel with preferable mechanical property, affording a suitable mechanical support for cartilage defect repair. Additionally, the robust tissue adhesion capability stemming from catechol groups guarantees the long-term retention of the hydrogel in the defect site. Meanwhile, L-MNS-CMDA hydrogel decomposes exogenous and intracellular H2O2 into O2 and H2O, to effectively alleviate cellular oxidative stress caused by long-term hypoxia. Under the synergies of catechol groups and MNS, L-MNS-CMDA hydrogel not only inhibits macrophages polarizing into M1 phenotype, but encourages them turn into M2 phenotype, thereby, reconstructing an immunization friendly microenvironment to ultimately enhance cartilage regeneration. Predictably, the hydrogel markedly induces rat bone marrow mesenchymal stem cells differentiating into chondrocytes by expressing abundant glycosaminoglycan and type II collagen. A cartilage defect model of rat knee joint indicates that L-MNS-CMDA hydrogel visually regulate the early inflammatory response of post-implantation, and facilitate cartilage regeneration and recovery of joint function after 12 weeks of post-implantation. All in all, this multifunctional L-MNS-CMDA hydrogel exhibits superior immunomodulatory and chondrogenic properties, holding immense clinical potential in the treatment of cartilage defects.

Harnessing gold-ion crosslinked polyphenol-mediated hydrogels with enhanced tissue adhesiveness, antioxidation, and antibacterial for advanced wound care

Improperly treated wounds can lead to infection, prolonged healing time, and severe health complications. Therefore, developing advanced wound healing materials with antibacterial properties, biocompatibility, and high adhesiveness is essential to support recovery and minimize risks. In this study, tannic acid-modified gelatin-based hydrogel was developed by crosslinking with gold ions, providing multiple properties to meet the requirements for wound healing. The conjugation of tannic acid (TA) on gelatin provides the hydrogel with antioxidative properties, while its ability to form multiple interactions ensures robust crosslinking and enhanced adhesion ability. Meanwhile, incorporating gold ions (Au3+) strengthens its mechanical properties and adds antibacterial effects. The hydrogel forms rapidly in about 10 seconds, featuring a porous structure and mechanical strength suitable for skin tissue. High tissue adhesion, demonstrated through UTM with an average value of 11.5 kPa, adds to its appeal. The hydrogel illustrated antioxidant capacity through DPPH assay and antibacterial ability against both E. coli and S. aureus, thanks to their inherited properties from TA and Au3+, respectively. The cytocompatibility of hydrogel was also demonstrated through WST-1 assay and live/dead staining, with cell viability for all samples over 82 %. These results underscore the potential of this hydrogel for advanced wound care applications.

Suture Bridge Fixation in Treating Traumatic Femoral Osteochondral Injuries in Adults: A Case Study and Review of the Literature.

Achieving anatomic reduction, securing fixation, and ensuring adequate compression are crucial steps in the internal fixation process for traumatic osteochondral defects. A variety of fixation methodologies have been in use, e.g., metal pins, bioabsorbable screws, and glue tissue adhesives, each of them yielding different outcomes. This study presents the outcomes of utilising the concept of suture bridge fixation for traumatic femoral osteochondral injury in a 34-year-old patient. Following a three-year follow-up, the patient demonstrated a return to normal activities with complete and pain-free knee mobility. In conclusion, it can be stated that suture bridges offer an alternative approach for the fixation of osteochondral fragments in the knee attributable to traumatic injuries.

Unveiling the impact of Leptospira TolC efflux protein on host tissue adherence, complement evasion, and diagnostic potential.

The TolC family protein of Leptospira is a type I outer membrane efflux protein. Phylogenetic analysis revealed significant sequence conservation among pathogenic Leptospira species (83%-98% identity) compared with intermediate and saprophytic species. Structural modeling indicated a composition of six β-strands and 10 α-helices arranged in two repeats, resembling bacterial outer membrane efflux proteins. Recombinant TolC (rTolC), expressed in a heterologous host and purified via Ni-NTA chromatography, maintained its secondary structural integrity, as verified by circular dichroism spectroscopy. Polyclonal antibodies against rTolC detected native TolC expression in pathogenic Leptospira but not in nonpathogenic ones. Immunoassays and detergent fractionation assays indicated surface localization of TolC. The rTolC's recognition by sera from leptospirosis-infected hosts across species suggests its utility as a diagnostic marker. Notably, rTolC demonstrated binding affinity for various extracellular matrix components, including collagen and chondroitin sulfate A, as well as plasma proteins such as factor H, C3b, and plasminogen, indicating potential roles in tissue adhesion and immune evasion. Functional assays demonstrated that rTolC-bound FH retained cofactor activity for C3b cleavage, highlighting TolC's role in complement regulation. The rTolC protein inhibited both the alternative and the classical pathway-mediated membrane attack complex (MAC) deposition in vitro. Blocking surface-expressed TolC on leptospires using specific antibodies reduced FH acquisition by Leptospira and increased MAC deposition on the spirochete. These findings indicate that TolC contributes to leptospiral virulence by promoting host tissue colonization and evading the immune response, presenting it as a potential target for diagnostic and therapeutic strategies.

Epidermal growth factor-incorporated hydrogen bond crosslinked hemostatic microparticles capable of timely response to accidental bleeding for prehospital rescue

Prehospital rescue of accidental massive bleeding is crucial for saving lives. However, currently available hemostatic materials are still in infancy in treating accidental bleeding due to the challenges in fully satisfying the complex outdoor hemostatic requirements. Herein, we designed an epidermal growth factor (EGF)- incorporated, microparticle-formed, high-strength, dynamic environment-stable hemostatic gel system for prehospital rescue. Carboxyl and dimethylamide were employed as the hydrogen bond (H-bond) groups and were carefully engineered into the microparticles (DHMs). We demonstrated that the unique H-bond crosslinked micronized structure enabled the DHM-based gelling system to adequately meet the outdoor hemostatic requirements. The stable H-bond groups allow the DHMs to be stored at room temperature and be easily carried around. The small sizes (150–250 μm) of the DHMs enabled the filling of irregular defects, and upon encountering water, these DHMs integrated into hydrogels (DHMs-gels) with high mechanical strength (1.61 MPa), strong tissue adhesiveness (66.5 kPa) and stable performance under dynamic environments. In vivo results showed that the EGF-incorporated DHMs-gels (DHMs-EGF gel) achieved a 100 % survival rate in a simulated rescue process and promoted wound healing. Simultaneously possessing multiple prehospital rescue-required properties, the hemostatic DHMs-EGF may become an effective tool for emergency rescue.

A randomized comparison of an adhesive gelatin sponge and a plain collagen sponge for hemostatic control during canine liver surgery.

To compare the effectiveness of a modified surface gelatin sponge to a plain collagen sponge for hemostasis of parenchymal hepatic bleeding. Prospective, randomized trial of two hemostatic agents. A total of 45 dogs undergoing elective liver surgery were randomly allocated into two groups: 22 in the adhesive gelatin (AG) group and 23 in the plain collagen (PC) group. A total of 20 patients per group underwent liver biopsy to create a uniformly sized bleeding surface, with the remaining patients (AG = 2, PC = 3) undergoing liver lobectomy. Evaluation of hemostatic effectiveness and tissue adhesion of each sponge type was performed by the operating surgeon using structured scoring systems. Hemostatic parameters were primarily evaluated at the liver biopsy site to maintain homogeneity of bleeding surface size. For the liver biopsy group (n = 40), 5 min after hemostatic sponge application, 10/20 dogs were bleeding in the PC group, compared to 2/20 in AG group (p = .0138). The PC bleeding was significantly higher than AG across the 3 to 6 min evaluation period (p < .001). When surgeons tested the adhesion of the sponge across the whole cohort (n = 45), AG scored 2 (of 3) against 1 for PC (p < .001). In group PC, 5/23 sponges dislodged during abdominal lavage and preparations for closure and had to be replaced due to recurrence of bleeding, compared with no AG sponges dislodging (p = .042). There were no further complications related to the use of either sponge. In the dogs with hepatic parenchymal incision, use of an adhesive gelatin sponge improved intraoperative attachment and haemostatic effectiveness, compared to a collagen sponge. Based on our clinical experience in these cases, adhesive gelatin sponges could be considered an effective option when selecting a hemostatic agent for liver surgery in dogs.

Mechanism of collagen type IV regulation by focal adhesion kinase during retained fetal membranes in dairy cows

Retained fetal membranes (RFM) is an important reproductive disease in dairy cows, caused by maternal and fetal placental tissue adhesion. The main collagen in maternal and fetal placenta tissues is collagen type IV (COL-IV) and its breakdown is the key to placental expulsion. Focal adhesion kinase (FAK) has been shown to regulate the hydrolysis of Col-IV by affecting the activity of MMP-2 and MMP-9 activity, but the regulation of the mechanisms involved in placenta expulsion in dairy cows after postpartum are still unclear. The aim of this study was to investigate the pathogenic mechanism of RFM by studying the relationship between the FAK signaling pathway and COL-IV regulation. Maternal placental tissues were collected from six healthy and six cows with RFM of similar age, parity, body condition and milk yield at 12 h postpartum. In vitro experiments were performed on bovine endometrial epithelial cells from three groups including a FAK inhibitor group, a FAK activator group and a control group without FAK inhibitor and activator. The abundance of molecules involved in the FAK signaling pathway and COL-IV was detected by immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. The immunohistochemical results showed that the key molecules of FAK signaling pathway FAK, Src, MMP-2 and MMP-9 and Col-IV were expressed in placental tissues. The expression level of FAK, Src, MMP-2, and MMP-9 were significantly down-regulated (P < 0.05) and the abundances of COL-IV were significantly up-regulated (P < 0.05) in maternal placental tissues of RFM cows compared with healthy cows. In the FAK inhibitor treatment group, the relative expression levels of FAK and other related proteins were significantly down-regulated (P < 0.05) and the relative expression levels of COL-IV were significantly up-regulated (P < 0.05) with the results of the FAK activation group the opposite. These results indicated that FAK in maternal endometrial epithelial cells could regulate the hydrolysis process of Col-IV through the expression of key factors of signaling pathways and promote collagen hydrolysis, which in turn facilitated the process of postpartum placenta expulsion in dairy cows.

Antibacterial and antioxidant supramolecular nanocomposite hydrogel dressings with angiogenesis and photo-thermal effect for multidrug‐resistant bacterial infected wound healing

Antioxidant, antibacterial and removable supramolecular nanocomposite hydrogel dressings with self-healing and tissue adhesiveness is highly anticipated for bacterial infected skin wound healing. A series of supramolecular nanocomposite hydrogels via quadruple hydrogen bond and coordination bonds (catechol-Cu) was developed based on ureidopyrimidinone-modified poly(glycerol sebacate)–co-poly(ethylene glycol)-g-catechol (PEGSDU) and mesoporous copper sulfide nanoparticle (CuS NPs) as antioxidative, antibacterial, removable and tissue-adhesive dressing to treat the MRSA-infected wound. The hydrogels exhibited good self-healing, free radical scavenging, photothermal sterilization performance, adhesiveness, and temperature-sensitive removability. In addition, the Cu2+ was able to be slowly released from the hydrogel, which can promote the proliferation and migration of fibroblasts. Hydrogels containing CuS NPs showed better wound repair efficiency than commercial TegadermTM films and hydrogels without CuS NPs in MRSA-infected skin wound, which was attributed to the good antibacterial property, improved collagen deposition, reduced inflammatory response, and improved new vessels formation, thereby significantly promoting the repair of wounds. In summary, this antioxidative and antibacterial supramolecular nanocomposite hydrogel dressing provide a new type of multi-functional dressing for the treatment of infected skin wounds.

Sticky Science: Using Complex Coacervate Adhesives for Biomedical Applications.

Tissue adhesives are used for various medical applications, including wound closure, bleeding control, and bone healing. Currently available options often show weak adhesion or cause adverse effects. Recently, there has been an increasing interest in complex coacervates as medical adhesives. Complex coacervates are formed by mixing oppositely charged macromolecules that associate and undergo liquid-liquid phase separation, in which the dense bottom phase is the complex coacervate. Complex coacervates are strong and often biocompatible, and show strong underwater adhesion. The properties of the resulting materials are tunable by intrinsic factors such as polymer chemistry, molecular weight, charge density, and topology of the macromolecules, as well as extrinsic factors such as temperature, pH, and salt concentration. Therefore, complex coacervates are interesting new candidates for medical adhesives. In this review, it is described how complex coacervates form and how different factors influence their behavior. Next, an overview of recent studies on complex coacervates in the context of medical adhesives is presented. The application of complex coacervates as hemostatic or embolic agents, skin or bone repair adhesives, and soft tissue sealants is discussed. Lastly, additional possibilities for utilizing these materials in the future are discussed.

Engineering injectable bioadhesives with sealing and anti-fouling properties for postoperative anti-adhesion

Postoperative adhesion is a common complication that follows various types of surgeries, causing patients suffering and increasing healthcare costs. Current anti-adhesion barriers fail to provide satisfactory therapeutic outcomes mainly due to their weak retention, inability to prevent fluid leakage, and potential foreign body reactions. In the present study, we fabricated a serine-modified bioadhesive (SESAgel) with improved sealing and anti-fouling properties for postoperative adhesion prevention. The resulting SESAgel exhibited good injectability and in-situ adhesion ability, forming a stable membranous anti-adhesion barrier on the wound surface. Innovatively, it possessed efficient sealing properties, effectively stopping the leakage of tissue fluid and blood, which triggers tissue adhesion formation in the early stage. On this basis, the anti-fouling property derived from the serine in this physical barrier can further prevent the accumulation of inflammatory cells and foreign body reactions, thereby minimizing tissue adhesion. Two animal models were used to demonstrate that SESAgel effectively inhibited postoperative adhesion in different surgeries. With its natural design and good biocompatibility, SESAgel is a promising anti-adhesion biomaterial for clinical translation and practice.

Injectable self-healing alginate/PEG hydrogels cross-linked via thiol-Michael addition bonds for hemostasis and wound healing

In this study, an alginate/PEG hydrogel was developed via a thiol-Michael addition reaction between oxidized quinone of catechols on dopamine-grafted sodium alginate (SA-DA) and sulfhydryl groups of 4-arm polyethylene glycol tetra-thiol (4-arm PEG-SH) under mildly basic conditions. Through the formation of thiol-terminated catechol groups, the accompanying oxidized catechols are reduced, significantly strengthening the internal network structure of the hydrogel and improving tissue adhesion. Meanwhile, the hydrogels have excellent self-healing properties due to the dynamic non-covalent bonds between the groups. Adjustment of hydrogel properties by varying the mass ratio of two hydrogel precursors. Due to the high content of thiol-terminated catechol groups, the Gel 3 exhibited good tissue adhesion, rapid self-healing ability, and other multifunctions beneficial to wound healing, including killing of E. coli and S. aureus, rapid hemostasis and promoting migration of L929 cells. The full-thickness skin wound model shows that the hydrogel dressing significantly accelerated wound contraction, with increased granulation tissue thickness, collagen disposition, and enhanced vascularization, thus promoting wound healing. Therefore, the thiol-Michael addition reaction is an effective method for creating multifunctional hydrogels, and the injectable self-healing alginate/PEG hydrogels prepared in this way could be used in the biomedical area as wound healing dressing materials.

Caffeic acid-mediated photodynamic multifunctional hyaluronic acid-gallic acid hydrogels with instant and enduring bactericidal potency accelerate bacterial infected wound healing

The emergence of drug-resistant bacteria poses significant challenges in wound treatment. Antimicrobial photodynamic therapy has emerged as an effective approach to eliminating bacteria by inducing oxidative stress without causing drug resistance. Here, we developed a natural hyaluronic acid (HA)-gallic acid (GA) conjugation-based hydrogel combined with herbal photosensitizer-caffeic acid (CA), which exhibits self-healing ability, shape adaptability, biodegradability, and robust tissue adhesion. Under exposure to 400 nm light, caffeic acid acts as a photosensitizer, generating reactive oxygen species and oxidative damage to bacterial cell membranes. Furthermore, the presence of GA and CA displayed a continuous inhibitory effect on bacterial growth, along with antioxidant properties that promote wound healing even after the cessation of light exposure. The antibacterial mechanism of the HA-GA/CA hydrogel against MRSA, S. aureus, and E. coli was investigated through various assays measuring ATP levels, Zeta potential, hydroxyl radicals (·OH) generated by light irradiation, and biofilm clearance rate. Additionally, hydrogel's application in treating MRSA-infected wounds in mice under light irradiation demonstrated rapid wound-healing effects and biocompatibility. Overall, HA-GA/CA hydrogel provides a sustainable, antibiotic-free alternative for treating MRSA-infected wounds.

Activation of muscle amine functional groups using eutectic mixture to enhance tissue adhesiveness of injectable, conductive and therapeutic granular hydrogel for diabetic ulcer regeneration

Herein, Polydopamine-modified microgels and microgels incorporated with superficial epoxy groups were synthesized and applied as precursors for the fabrication of four granular hydrogels. To enhance the tissue adhesiveness, a ternary deep eutectic solvent was synthesized to activate the muscle amine functional groups facilitating the formation of robust NC bonds at ambient conditions. At a certain shear rate of 10 s−1, hydrogel DMG displayed a viscosity of 9×103 Pa/s, representing the highest complex viscosity among the tested hydrogels primarily driven by quinone groups in PDA which enhanced reversible interactions, thereby increasing particle cohesion. Moreover, the intersection point escalating from about 4×103 to approximately 9×104 as the concentration of DMG increased from 0 % (for MG) to 70% (7D3MG) by weight. There was a decrease in adhesion strength from 0.45 ± 0.08 N in MG to 0.39 ± 0.16 N, 0.35± 0.18 N, and 0.33 ± 0.15 N for 3D7MG, 7D3MG, and DMG respectively, suggesting that MG was capable of forming numerous covalent bonds, thereby enhancing its adhesion to the substrate. The type of eutectic mixture affected the electrical conductivity and a very important point was the changes in resistance value with time. For MG catalyzed by [DES]AZG, the resistance increased only by 1.3 % (from 3.37 to 3.81 kΩ) at day 3 and 37.09 % (from 3.37 to 4.62 kΩ) at day 5. The 3D7MG hydrogel exhibited superior therapeutic efficacy toward diabetic wound regeneration. The proliferation index value for 3D7MG-[DES]AZG and 3D7MG-[DES]AG were calculated 42.3 % and 58.6 %, respectively, while the control group exhibited a lower value of 37.8 %.

A molecular docking insight: Phyllanthus niruri L. constituents targeting MMP-9 for angiogenesis inhibition and IL-1beta for antiinflammatory action in endometriosis therapy

Endometriosis, characterized by inflammatory lesions resembling endometrium outside the uterine cavity, induces chronic inflammation, anatomical changes and persistent pain. The expression of Interleukin 1beta (IL-1beta) is significantly associated with endometriosis, contributing to inflammatory process and fertility issues. Matrix metalloproteinase 9 (MMP-9) is crucial in the adhesion and angiogenesis of endometrial tissue. This study investigates the potential of Phyllanthus niruri L. in inhibiting MMP-9 and IL-1beta through molecular docking analysis. Molecular docking was performed using Discovery Studio Visualizer, Open Babel, PyRx and AutoDock Vina. The inhibitory activities of bioactive compounds on MMP-9 and IL-1beta were predicted. Biological activity and cytotoxicity were assessed using PASS and CLC-Pred respectively. Kaempferol and quercetin from P. niruri exhibited significant MMP-9 expression inhibitory activity. Search Tool for Interacting Chemicals (STITCH) analysis revealed interactions of quercetin and galangin with specific proteins involved in pathways related to endometriosis. Biological activity analysis indicated that quercetin, kaempferol, herbacetin and galangin show potential as MMP -9 expression inhibitors. CLC-Pred analysis suggested high cytotoxicity of kaempferol against glioma. Molecular docking results showed quercetin's potential as an MMP-9 inhibitor and galangin's potential as an IL-1 beta inhibitor. These findings support the therapeutic potential of P. niruri for endometriosis, providing insights for further research in developing innovative therapies targeting endometriosis-related inflammation and angiogenesis.

A multifunctional hydrogel dressing loaded with antibiotics for healing of infected wound

Wound bacterial infections can significantly delay the healing process and even lead to fetal sepsis. There is a need for multifunctional dressings that possess antibacterial property, tissue adhesive property, self-healing capability, and biocompatibility to effectively treat bacteria-infected wound. In this study, we report a dual dynamically crosslinked hydrogel, OHA-PBA/PVA/Gen, which incorporates the antibiotic gentamicin (Gen) as a dynamic crosslinker. The hydrogel is formed through the formation of Schiff base bonds between phenylboronic acid-grafted oxidized hyaluronic acid (OHA-PBA) and Gen, as well as boronic acid ester bonds between OHA-PBA and polyvinyl alcohol (PVA). This unique composition imparts tissue adhesiveness, injectability and self-healing property to the hydrogel. The hydrogel also exhibits pH-responsive antibiotic release behavior due to the acid-responsive dissociation of Schiff base bonds. As a result, it demonstrates strong antibacterial activity against both Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli through contact killing and diffusion killing mechanisms. Importantly, the OHA-PBA/PVA/Gen hydrogel avoids incorporation of toxic small molecular crosslinking agents, and all the components of the hydrogel are biocompatible, ensuring its biosafety. In a S. aureus-infected wound mouse model, this hydrogel effectively eradicated bacteria and promoted angiogenesis, leading to significantly accelerated wound healing. These results highlight the potential of the dual dynamically crosslinking hydrogel OHA-PBA/PVA/Gen as a multifunctional wound dressing for the treatment of bacteria-infected wound.

Orthodontic-Orthognathic Management of a Patient With Severe Mandibular Deficiency Due to Bicondylar Fracture: A Case Report

This case report is about a 30-year-old Iranian female. The patient’s chief complaint was the backwardness of the lower jaw. The patient reported a history of condylar fractures in childhood. There was crowding in the maxillary and mandibular arch, and the midline in the mandible was 2 mm deviated to the left. The canine and first premolar on the left side of the maxilla were extracted, and the canine on the left side of the mandible was impacted. Clinical examinations and paraclinical documents revealed that the patient was a skeletal class II case with mandibular deficiency, complicated by a vertical maxillary excess. Virtual surgery planning was used to plan the patient’s treatment. The amount of adhesion of soft tissue to hard tissue was also taken into consideration. According to the measurements of the patient and the class II, vertical maxillary excess of the patient, the shortness of the ramus, and the large angle of the occlusal plane, our chosen orthognathic surgery included bilateral sagittal split osteotomy, advancement genioplasty, and maxillary impaction.

Janus-Structured Microgel Barrier with Tissue Adhesive and Hemostatic Characteristics for Efficient Prevention of Postoperative Adhesion.

Postoperative adhesion (POA) is a common and serious complication following various types of surgery. Current physical barriers either have a short residence time at the surgical site with a low tissue attachment capacity or are prone to undesired adhesion formation owing to the double-sided adhesive property, which limits the POA prevention efficacy of the barriers. In this study, Janus-structured microgels (Janus-MGs) with asymmetric tissue adhesion capabilities are fabricated using a novel bio-friendly gas-shearing microfluidic platform. The anti-adhesive side of Janus-MGs, which consists of alginate, hyaluronic acid, and derivatives, endows the material with separation, lubrication, and adhesion prevention properties. The adhesive side provided Janus-MGs with tissue attachment and retention capability through catechol-based adhesion, thereby enhancing the in situ adhesion prevention effect. In addition, Janus-MGs significantly reduced blood loss and shortened the hemostatic time in rats, further reducing adhesion formation. Three commonly used rat POA models with different tissue structures and motion patterns are established in this study, namely peritoneal adhesion, intrauterine adhesion, and peritendinous adhesion models, and the results showed that Janus-MGs effectively prevented the occurrence of POA in all the models. The fabrication of Janus-MGs offers a reliable strategy and a promising paradigm for preventing POA following diverse surgical procedures.

Spatial Transcriptomic Profiling of Human Saphenous Vein Exposed to Ex Vivo Arterial Haemodynamics-Implications for Coronary Artery Bypass Graft Patency and Vein Graft Disease.

Vein graft disease is the process by which saphenous vein grafts, utilised for revascularisation during coronary artery bypass graft surgery, undergo an inflammation-driven intimal hyperplasia and accelerated atherosclerosis process in subsequent years after implantation. The role of the arterial circulation, particularly the haemodynamic properties' impact on graft patency, have been investigated but have not to date been explored in depth at the transcriptomic level. We have undertaken the first-in-man spatial transcriptomic analysis of the long saphenous vein in response to ex vivo acute arterial haemodynamic stimulation, utilising a combination of a custom 3D-printed perfusion bioreactor and the 10X Genomics Visium Spatial Gene Expression technology. We identify a total of 413 significant genes (372 upregulated and 41 downregulated) differentially expressed in response to arterial haemodynamic conditions. These genes were associated with pathways including NFkB, TNF, MAPK, and PI3K/Akt, among others. These are established pathways involved in the initiation of an early pro-inflammatory response, leukocyte activation and adhesion signalling, tissue remodelling, and cellular differentiation. Utilising unsupervised clustering analysis, we have been able to classify subsets of the expression based on cell type and with spatial resolution. These findings allow for further characterisation of the early saphenous vein graft transcriptional landscape during the earliest stage of implantation that contributes to vein graft disease, in particular validation of pathways and druggable targets that could contribute towards the therapeutic inhibition of processes underpinning vein graft disease.

Optimized microvascular decompression surgery for improving the results of hemifacial spasm: an analysis of reoperations.

Microvascular decompression (MVD) surgery is an effective curative treatment for hemifacial spasm (HFS). This study aims to establish techniques that may lead to favorable outcomes by analyzing reoperations in patients with persistent or recurrent HFS.Patients who exhibited persistent or recurrent HFS symptoms after prior MVD surgery were identified as candidates for reoperation. Information regarding the reoperations was collected by tracing the entire surgical procedures and peri-operative management. Clinical manifestations and follow-up data were obtained from the hospital records and subsequent visits.Twenty-six patients underwent repeat MVD surgery. Among them, multi-culprit neurovascular compression (NVC) was identified as the primary cause of failure to response to the previous operation in 73.08% of cases. Pure tissue adhesion accounted for 38.46% of cases, while shredded Teflon pledget (STP) shifting was observed in 7.69% of cases. Postoperative outcomes were assessed through revisits and categorized into four groups: excellent (76.92%), good (15.38%), fair (7.69%), and poor (0%). The longest follow-up period exceeded 65 moths.The trans-lateral suboccipital infra-floccular approach provides a better visual field. Examination of entire length of the facial nerve is essential. STP with gelatin sponge implantation is a suitable material for facilitating nerve and vascular positioning and reducing adhesion.