Prevention Of Postoperative Adhesions Research Articles

Injectable polyamide-amine dendrimer-crosslinked meloxicam-containing poly-γ-glutamic acid hydrogel for prevention of postoperative tissue adhesion through inhibiting inflammatory responses and balancing the fibrinolytic system

Establishing a physical barrier between the peritoneum and the cecum is an effective method to reduce the risk of postoperative abdominal adhesions. Meloxicam (MX), a nonsteroidal anti-inflammatory drug has also been applied to prevent postoperative adhesions. However, its poor water solubility has led to low bioavailability. Herein, we developed an injectable hydrogel as a barrier and drug carrier for simultaneous postoperative adhesion prevention and treatment. A third-generation polyamide-amine dendrimer (G3) was exploited to dynamically combine with MX to increase the solubility and the bioavailability. The formed G3@MX was further used to crosslink with poly-γ-glutamic acid (γ-PGA) to prepare a hydrogel (GP@MX hydrogel) through the amide bonding. In vitro and in vivo experiments evidenced that the hydrogel had good biosafety and biodegradability. More importantly, the prepared hydrogel could control the release of MX, and the released MX is able to inhibit inflammatory responses and balance the fibrinolytic system in the injury tissues in vivo. The tunable rheological and mechanical properties (compressive moduli: from ∼ 57.31 kPa to ∼ 98.68 kPa;) and high anti-oxidant capacity (total free radical scavenging rate of ∼ 94.56 %), in conjunction with their syringeability and biocompatibility, indicate possible opportunities for the development of advanced hydrogels for postoperative tissue adhesions management.

Janus Nanofibrous Patch with In Situ Grown Superlubricated Skin for Soft Tissue Repair with Inhibited Postoperative Adhesion.

The patch with a superlubricated surface shows great potential for the prevention of postoperative adhesion during soft tissue repair. However, the existing patches suffer from the destruction of topography during superlubrication coating and lack of pro-healing capability. Herein, we demonstrate a facile and versatile strategy to develop a Janus nanofibrous patch (J-NFP) with antiadhesion and reactive oxygen species (ROS) scavenging functions. Specifically, sequential electrospinning is performed with initiators and CeO2 nanoparticles (CeNPs) embedded on the different sides, followed by subsurface-initiated atom transfer radical polymerization for grafting zwitterionic polymer brushes, introducing superlubricated skin on the surface of single nanofibers. The poly(sulfobetaine methacrylate) brush-grafted patch retains fibrous topography and shows a coefficient of friction of around 0.12, which is reduced by 77% compared with the pristine fibrous patch. Additionally, a significant reduction in protein, platelet, bacteria, and cell adhesion is observed. More importantly, the CeNPs-embedded patch enables ROS scavenging as well as inhibits pro-inflammatory cytokine secretion and promotes anti-inflammatory cytokine levels. Furthermore, the J-NFP can inhibit tissue adhesion and promote repair of both rat skin wounds and intrauterine injuries. The present strategy for developing the Janus patch exhibits enormous prospects for facilitating soft tissue repair.

Prevention of post-operative adhesions: Model development and pilot outcomes of human placental stem cell-based interventions.

Abdominal adhesions are the most common surgical complication and without reliable prophylactics. This study presents a novel rat model for abdominal adhesions and reports pilot results of human placental stem cell (hPSC)-based therapies. Forty-four (n = 44) male Sprague-Dawley rats (250-350 g) were used in the experiment. Of these, thirty-eight (n = 38) were included in a preliminary data set to determine a minimum treatment effect. Adhesions were created in a reproducible model to the abdominal wall and between organs. Experimental groups included the control group (Model No Treatment, MNT), Plasmalyte A (Media Alone, MA, 10 mL), hPSC (5 × 106 cells/10 mL Plasmalyte A), hPSC-CM (hPSC secretome, conditioned media) in 10 mL Plasmalyte A, Seprafilm™ (Baxter, Deerfield, IL), and sham animals (laparotomy only). Treatments were inserted intraperitoneally (IP) and the study period was 14 days post-operation. Results are reported as the difference between means of an index statistic (AIS, Animal Index Score) and compared by ANOVA with pairwise comparison. The overall mean AIS was 23 (SD 6.16) for the MNT group with an average of 75% of ischemic buttons involved in abdominal adhesions. Treatment groups MA (mean overall AIS 17.33 SD 6.4), hPSC (mean overall AIS 13.86 SD 5.01), hPSC-CM (mean overall AIS 13.13 SD 6.15), and Seprafilm (mean overall AIS 13.43 SD 9.11) generated effect sizes of 5.67, 9.14, 9.87, and 9.57 decrease in mean overall AIS, respectively, versus the MNT. The presented rat model and scoring system represent the clinical adhesion disease process. hPSC-based interventions significantly reduce abdominal adhesions in this pilot dataset.

A low-swelling hydrogel as a multirole sealant for efficient dural defect sealing and prevention of postoperative adhesion

Abstract Dural defects and subsequent complications, including cerebrospinal fluid (CSF) leakage, are common in spine surgery and neurosurgery, and existing clinical treatments are still unsatisfactory. In this study, a tissue-adhesive and low-swelling hydrogel sealant comprising gelatin and o-phthalaldehyde (OPA)-terminated 4-armed poly(ethylene glycol) (4aPEG-OPA) is developed via the OPA/amine condensation reaction. The hydrogel shows an adhesive strength of 79.9 ± 12.0 kPa on porcine casing and a burst pressure of 208.0 ± 38.0 cmH2O. The hydrogel exhibits a low swelling ratio at physiological condition, avoiding nerve compression in the limited spinal and intracranial spaces. In rat and rabbit models of lumbar and cerebral dural defects, the 4aPEG-OPA/gelatin hydrogel achieves excellent performance in dural defect sealing and preventing CSF leakage. Moreover, local inflammation, epidural fibrosis and postoperative adhesion in the defect areas are markedly reduced. Thus, these findings establish the strong potential of the hydrogel sealant for the effective watertight closure of dural defects.

ROS-responsive sprayable hydrogel as ROS scavenger and GATA6+ macrophages trap for the prevention of postoperative abdominal adhesions

Postoperative abdominal adhesions are a common clinical problem after surgery and can cause many serious complications. Current most commonly used antiadhesion products are less effective due to their short residence time and focus primary on barrier function. Herein, we developed a sprayable hydrogel barrier (sHA-ADH/OHA-E) with self-regulated drug release based on ROS levels at the trauma site, to serve as a smart inflammatory microenvironment modulator and GATA6+ macrophages trap for non-adherent recovery from abdominal surgery. Sulfonated hyaluronic acid (HA) conjugates modified with adipic dihydrazide (sHA-ADH), and oxidized HA conjugates grafted with epigallocatechin-3-gallate (EGCG) via ROS-cleavable boronate bonds (OHA-E) were synthesized. sHA-ADH/OHA-E hydrogel was facilely fabricated within 5 s after simply mixing sHA-ADH and OHA-E through forming dynamic covalent acylhydrazones. With good biocompatibility, appropriate mechanical strength, tunable shear-thinning, self-healing, asymmetric adhesion, and reasonable in vivo retention time, sHA-ADH/OHA-E hydrogel meets the requirements of a perfect physical barrier. Intriguingly, sulfonic acid groups endowed the hydrogel with satisfactory anti-fibroblast and macrophage attachment capability, and were demonstrated for the first time to act as polyanion traps to prevent GATA6+ macrophages aggregation. Importantly, EGCG could be intelligently released by ROS triggering to alleviate oxidative stress and promote proinflammatory M1 macrophage polarize to antiinflammatory M2 phenotype. Further, the fibrinolytic system balance was restored to reduce fibrosis. Thanks to the above advantages, the sHA-ADH/OHA-E hydrogel exhibited excellent anti-adhesion effects in a rat sidewall defect–cecum abrasion model and is expected to be a promising and clinically translatable antiadhesion barrier.

A Graphene Composite Film Based Wearable Far-Infrared Therapy Apparatus (GRAFT) for Effective Prevention of Postoperative Peritoneal Adhesion.

Postoperative peritoneal adhesion (PPA) is the most frequent complication after abdominal surgery. Current anti-adhesion strategies largely rely on the use of physical separating barriers creating an interface blocking peritoneal adhesion, which cannot reduce inflammation and suffers from limited anti-adhesion efficacy with unwanted side effects. Here, by exploiting the alternative activated macrophages to alleviate inflammation in adhesion development, a flexible graphene-composite-film (F-GCF) generating far-infrared (FIR) irradiation that effectively modulates the macrophage phenotype toward the anti-inflammatory M2 type, resulting in reduced PPA formation, is designed. The anti-adhesion effect of the FIR generated by F-GCF is determined in the rat abdominal wall abrasion-cecum defect models, which exhibit reduced incidence and area of PPA by 67.0% and 92.1% after FIR treatment without skin damage, significantly superior to the clinically used chitosan hydrogel. Notably, within peritoneal macrophages, FIR reduces inflammation reaction and promotes tissue plasminogen activator (t-PA) level via the polarization of peritoneal macrophages through upregulating Nr4a2 expression. To facilitate clinical use, a wirelessly controlled, wearable, F-GCF-based FIR therapy apparatus (GRAFT) is further developed and its remarkable anti-adhesion ability in the porcine PPA model is revealed. Collectively, the physical, biochemical, and in vivo preclinical data provide compelling evidence demonstrating the clinical-translational value of FIR in PPA prevention.

Ultrasmall ruthenium nanozyme with RONS scavenging and anti-inflammatory effects for effective prevention of postoperative peritoneal adhesion

Postoperative peritoneal adhesion is one of the most common complications after abdominal and pelvic surgery. Early inflammatory response and oxidative stress induced by peritoneal injury play important roles in adhesion formation. However, current research mainly focuses on developing barrier materials to physically separate injury sites for preventing peritoneal adhesions, but often ignores the pathologic changes promoting adhesion formation, resulting in unsatisfactory outcomes. Herein we report a versatile nanozyme (ultrasmall ruthenium nanoparticles, RuNPs) with great antioxidant and anti-inflammatory effects targeting the intrinsic causes of peritoneal adhesions. RuNPs sufficiently protect mesothelial cells from oxidative stress by scavenging reactive species and suppress inflammatory response via NF-κB pathway blockade. In rats with cecum abrasion-abdominal wall defect, RuNPs alone or combined with barrier material effectively prevent adhesion formation and promote injured tissue healing through alleviating oxidative stress and inflammation. This study not only generates a promising nano-agent for preventing adhesions but also provides a novel therapeutic strategy by targeting the underlying causation of adhesion formation.

Adhesive Nanoparticle-in-Microgel System with ROS Scavenging Capability and Hemostatic Activity for Postoperative Adhesion Prevention.

Postoperative adhesion is a noteworthy clinical complication in abdominal surgery due to the existing physical barriers are unsatisfactory and inefficient in preventing its occurrence. In this work, an elaborate nanoparticle-in-microgel system (nMGel) is presented for postoperative adhesion prevention. nMGel is facilely formed by crosslinking manganese dioxide (MnO2 ) nanoparticles-loaded gelatin microspheres with polydopamine using a modified emulsification-chemical crosslinking method, generating a nano-micron spherical hydrogel. After drying, powdery nMGel with sprayability can perfectly cover irregular wounds and maintains robust tissue adhesiveness even in a wet environment. Additionally, nMGel possesses prominent antioxidant and free radical scavenging activity, which protects cell viability and preserves cell biological functions in an oxidative microenvironment. Furthermore, nMGel displays superior hemostatic property as demonstrated in mouse tail amputation models and liver trauma models. Importantly, nMGel can be conveniently administrated in a mouse cecal defect model to prevent adhesion between the injured cecum and the peritoneum by reducing inflammation, oxidative stress, collagen synthesis, and angiogenesis. Thus, the bioactive nMGel offers a practical and efficient approach for ameliorating postsurgical adhesion.

A rapid crosslinking injectable polygalacturonic acid barrier modified with zwitterion bottlebrush for preventing postoperative adhesion

Postoperation adhesion, as a worldwide problem, are often accompanied by serious complications and cause severe pain to patients, and traditional medicines and commercial anti-adhesion barriers have limited protective effects. So, we designed a novel injective, antifouling and photo-crosslinked polygalacturonic acid (PGA) hydrogel barrier composed of PGA methacrylate (PGAMA) and 2-methacryloyloxyethyl phosphorylcholine (MPC) with excellent effect of covering the wound and preventing adhesion. The product termed, as PGAMA-MPC, enhanced hydration as expected with the introduction of abundant MPC, showing an obvious resistance to protein, cell, and microorganism. Simultaneously, as injectable medical materials, stable attachment to the wound and low invasiveness for tissue were provided by photo-crosslinking of PGAMA-MPC hydrogel during Minimally invasive surgery. In the rat model of cecal injury, the PGAMA-MPC hydrogel effectively prevented the postoperative peritoneal adhesion, showing an obvious protective effect within 7 d and the excellent ability to repair of cecum and abdominal wall after 14 d. Compared with the control group, the rats treated with PGAMA-MPC3 almost recovered to the level of the normal level. Furthermore, we found that PGAMA-MPC3 hydrogel significantly reduced the expression of inflammation and deposition of fibrin. The underlying mechanism of anti-adhesion was subsequently confirmed by analyzing the signaling pathway TGF-β1. The PGA-MPC3 hydrogel promoted fibrinolysis by blocking the activation of TGF-β1/Smad3 pathway. In conclusion, we developed an available polysaccharide hydrogel for rapid repair of peritoneum and prevention of postoperative adhesion, possessing an extensive application as medical materials.

A novel barrier membrane with long-term ROS scavenging function for complete prevention of postoperative adhesion

Local oxidative stress induced by surgical trauma has been recognized as one of pathogenesis for postsurgical adhesion tissue formation. Herein, tannic acid (TA) based metal-phenolic networks (MPNs) was assembled via chelating with Fe3+, and acted as a novel bio-filler for nanofibrous polycaprolactone (PCL) barrier membrane to endow it with reactive oxygen species (ROS) scavenging capacity. By chelating with Fe3+, the release of TA could last for more than 20 days, rendering the membrane with continuous ROS scavenging capacity. The modified membrane could effectively inhibit fibroblasts adhesion and proliferation, as well as immune cells recruitment, infiltration, and expression of pro-inflammatory cytokines. Consequently, a complete prevention of peritoneal adhesion formation was obtained in a rat model of sidewall defect-cecum abrasion, far better than commercial Poly lactic acid (PLA) membrane. Systematic biological mechanism investigations revealed that the enhanced anti-adhesion function was mainly ascribed to its robust ROS scavenging capacity, through which the PI3K-Akt signaling pathway was blocked, leading to repress of downstream NF-κB-TGFβ1-SMAD signaling pathway, finally inhibiting the bioactivity of fibroblasts and immune cells. This work provided a new strategy for the design of advanced barrier membrane, demonstrated its efficacy and mechanism on preventing postoperative adhesion, holding great promise for future clinical application.

Biosafe Polydopamine-Decorated MnO2 Nanoparticles with Hemostasis and Antioxidative Properties for Postoperative Adhesion Prevention.

Surgical bleeding and cumulative oxidative stress are significant factors in the development of postoperative adhesions, which are always associated with adverse patient outcomes. However, effective strategies for adhesion prevention are currently lacking in clinical practice. In this study, we propose a solution using polydopamine-decorated manganese dioxide nanoparticles (MnO2@PDA) with rapid hemostasis and remarkable antioxidant properties to prevent postsurgical adhesion. The PDA modification provides MnO2@PDA with enhanced tissue adhesiveness and hemocompatibility with negligible hemolysis. Furthermore, MnO2@PDA exhibits impressive antioxidant and free radical scavenging properties, protecting cells from the negative effects of oxidative stress. The hemostatic activity of MnO2@PDA is evaluated in a mouse truncated tail model and a liver injury model, with results demonstrating reduced bleeding time and volume. The in vivo test on a mouse cecal abrasion model shows that MnO2@PDA exhibits excellent antiadhesion properties coupled with alleviated inflammation around the damaged tissue. Therefore, MnO2@PDA, which exhibits high biosafety, rapid hemostasis, and beneficial antioxidant capacity, displays exceptional antiadhesion performance, holding great potential for clinical applications to prevent postoperative adhesion.

Modelling and prevention of postoperative adhesions in gynaecological and pelvic surgery in experiment: morphological and ultrastructural features

Modelling and prevention of postoperative adhesions in gynaecological and pelvic surgery in experiment: morphological and ultrastructural features

Injectable Asymmetric Adhesive-Antifouling Bifunctional Hydrogel for Peritoneal Adhesion Prevention.

Peritoneal adhesion is a common problem after abdominal surgery and can lead to various medical problems. In response to the lack of in situ retention and pro-wound healing properties of existing anti-adhesion barriers, this work reports an injectable adhesive-antifouling bifunctional hydrogel (AAB-hydrogel). This AAB-hydrogel can be constructed by "two-step" injection. The tissue adhesive hydrogel based on gallic acid-modified chitosan and aldehyde-modified dextran is prepared as the bottom hydrogel (B-hydrogel) by Schiff base reaction. The aldehyde-modified zwitterionic dextran/carboxymethyl chitosan-based hydrogel is formed on the B-hydrogel surface as the antifouling top hydrogel (T-hydrogel). The AAB-hydrogel exhibits good bilayer binding and asymmetric properties, including tissue adhesive, antifouling, and antimicrobial properties. To evaluate the anti-adhesion effect in vivo, the prepared hydrogels are injected onto the wound surface of a mouse abdominal wall abrasion-cecum defect model. Results suggest that the AAB-hydrogel has antioxidant capacity and can reduce the postoperative inflammatory response by modulating the macrophage phenotype. Moreover, the AAB-hydrogel could effectively inhibit the formation of postoperative adhesions by reducing protein deposition, and resisting fibroblast adhesions and bacteria attacking. Therefore, AAB-hydrogel is a promising candidate for the prevention of postoperative peritoneal adhesions.

Degradable carrier-free spray hydrogel based on self-assembly of natural small molecule for prevention of postoperative adhesion.

Postoperative peritoneal adhesion (PPA) is frequent and extremely dangerous complication after surgery. Different tactics have been developed to reduce it. However, creating a postoperative adhesion method that is multifunctional, biodegradable, biocompatible, low-toxic but highly effective, and therapeutically applicable is still a challenge. Herein, we have prepared a degradable spray glycyrrhetinic acid hydrogel (GAG) based on natural glycyrrhetinic acid (GA) by straightforward heating and cooling without the use of any additional chemical cross-linking agents to prevent postoperative adhesion. The resultant hydrogel was demonstrated to possess various superior anti-inflammatory activity, and multiple functions, such as excellent degradability and biocompatibility. Specifically, spraying characteristic and excellent antibacterial activities essentially eliminated secondary infections during the administration of drugs in surgical wounds. In the rat models, the carrier-free spray GAG could not only slow-release GA to inhibit inflammatory response, but also serve as physical anti-adhesion barrier to reduce collagen deposition and fibrosis. The sprayed GAG would shed a new light on the prevention of postoperative adhesion and broaden the application of the hydrogels based on natural products in biomedical fields.

Quercetin inhibits mesothelial-mesenchymal transition and alleviates postoperative peritoneal adhesions by blocking the TGF-β1/PI3K/AKT pathway

Ethnopharmacological relevanceCarthami flos is a dried flower of the Asteraceae plant Carthamus tinctorius (L.). Danhong injection, composed of Carthami flos and Danshen can prevent the formation of postoperative peritoneal adhesions. Quercetin (QUE), an active compound of Carthami flos, has also been proved to prevent postoperative abdominal and uterine cavity adhesions. However, whether QUE is the key component in Carthami flos and the mechanism in preventing postoperative peritoneal adhesions has not been studied. Aim of the studyTo predict whether QUE is the key molecule in Carthami flos and explore the effect and mechanism of QUE in preventing postoperative peritoneal adhesions. Materials and methodsDrug composition and target analysis was used to predict the key component in Carthami flos. The method of cecum-sidewall abrasion was used to establish adhesion models, and the antiadhesion effect of QUE was evaluated with the adhesion scoring system. Network pharmacology was used to predict the targets and potential mechanism of QUE in preventing adhesion. The mechanism was further verified by immunofluorescence, Western blot, wound healing experiment, and molecular docking. ResultsQuercetin was predicted to be the key to preventing postoperative peritoneal adhesions in Carthami flos. Animal experiments revealed that QUE effectively ameliorated adhesions and reduced the expression of mesothelial-mesenchymal transition (MMT) related markers and TGF-β1. Moreover, the TGF-β1/PI3K/AKT pathway was predicted via protein-protein interaction and Kyoto encyclopedia of Genes and Genomes enrichment analysis to play a crucial part in preventing adhesion by QUE. Furthermore, in vitro experiments and molecular docking demonstrated that QUE could block the TGF-β1/PI3K/AKT pathway through forming a stable combination with TβR-II, thereby inhibiting MMT and ameliorating peritoneal adhesion. ConclusionsQUE can not only reduce postoperative TGF-β1 but also block the TGF-β1/PI3K/AKT pathway to inhibit MMT of mesothelial cells, and finally alleviate postoperative peritoneal adhesions. These findings may provide insights towards development of a safe and effective anti-adhesive drug for prevention of postoperative peritoneal adhesions.

Antifouling and Injectable Granular Hydrogel for the Prevention of Postoperative Intrauterine Adhesion.

Postoperative intrauterine adhesion (IUA), caused by endometrial basal layer injury, is one of the main causes of female infertility. The excessive deposition of fibrin as well as fibroblast is considered the root cause of IUA. However, few clinical strategies are effective in preventing extracellular matrix (ECM) deposition at endometrial wounds that include protein and cell deposits. Herein, the injectable granular poly(N-(2-hydroxyethyl) acrylamide) (PHEAA) hydrogel (granular PHEAA gel), which presents excellent antifouling properties and remarkably prevents protein and cell adhesions, is used to prevent postoperative IUA. The granular PHEAA gel with a jammed network structure exhibits outstanding injectability and superior stability. Compared with the IUA group, the granular PHEAA gel can promote regeneration of the endometrium while reducing the area of endometrial fibrosis. Immunohistochemical staining experiments indicate that the granular PHEAA gel can improve the proliferation of the endometrium, promote vascularization, and enhance anti-inflammatory effect in IUA rats. And the granular PHEAA gel can effectively slow down the fibrosis of uterine tissue. Importantly, the number of embryos is significantly increased after injecting granular PHEAA gel, inferring that there is an obvious reproductive function recovery of injured endometrium.

Recent advances in the preventative strategies for postoperative adhesions using biomaterial-based membranes and micro/nano-drug delivery systems

Postoperative adhesions are one of the clinically significant complications of almost all surgeries, leading to lifelong problems. To date, three strategies have been introduced to prevent or reduce the formation of these fibrous bands, including implementation of physical barriers, local or systemic administration of pharmacological agents, or a combination of both at the site of postsurgical traumatized tissue. This so far unsolved challenge has prompted scientists to focus on developing more effective preventative therapies. In this review, we aimed to provide a detailed overview of drug-free and drug-incorporated anti-adhesion barrier membranes and micro/nano-drug delivery systems implemented for postoperative adhesion prevention. The formulation components, the mean particle sizes of the particulate-based systems, release behavior of pharmacologic agents, and various evaluation methods determining the in vivo efficacy of the prepared systems in animal models including scoring, gross evaluation, Western blot, polymerase chain reaction (PCR), tissue scanning electron microscopy (SEM), enzyme-linked immunosorbent assay (ELISA), histological and immunohistochemical analyses were identified and discussed. Although a great number of studies have focused on the preparation and evaluation of the anti-adhesion efficacy of drug-free or drug-loaded anti-adhesion systems, further sophisticated research is required to develop effective and safe anti-adhesion products for clinical application.

Effectiveness of hyaluronic acid-based anti-adhesion gel for intraoperative prevention of postoperative adhesions in surgical correction of distal occlusion of the fallopian tubes: Prospective cohort study

Aim. To evaluate the effectiveness of hyaluronic acid anti-adhesion gel in surgical correction of distal tubal occlusion in restoring natural fertility in patients with infertility.
 Materials and methods. A prospective cohort study was conducted. The main group (group 1) included 54 women; the comparison group (group 2) included 58 women with tuboperitoneal infertility due to distal occlusion of the fallopian tubes. In group 1 patients, at the final stage of endoscopic reconstructive plastic surgery on the surface of the fallopian tubes, anti-adhesion barrier Anti-adhesion was applied (5 mL per each operated fallopian tube). Primary outcomes (patency of the fallopian tubes after 3 months) and secondary outcomes (onset of uterine pregnancy during the first year) were assessed. Statistical results were processed using the IBM SPSS Statistics version 25.0 software package.
 Results. Within 3 months after surgical treatment, the patency of the fallopian tubes was reported in 32 (59.3%) group 1 patients and 24 (41.4%) group 2 patients (2=3.445; p=0.064). The rate of uterine pregnancy in group 1 during the first year after surgical treatment was significantly higher than in group 2: 21 (38.9%) and 12 (20.7%) women, respectively (2=4.447; p=0.035).
 Conclusion. Endoscopic reconstructive plastic surgeries using hyaluronic acid-based anti-adhesion gel in patients with distal tubal occlusion slightly reduces the frequency of postoperative reocclusions of the fallopian tubes within 3 months after surgical treatment and significantly increase the rate of uterine pregnancy during the year after surgery mainly due to patients with grade IIIIV of adhesive process in the pelvis.

A unidirectional drug‐release Janus membrane based on hydrogen bonding barrier effect for preventing postoperative adhesion and promoting tissue repair

AbstractBarrier membranes incorporated with anti‐adhesion drugs have been widely used for preventing postoperative adhesion. However, the bidirectional release of drugs may interfere with internal tissue healing. Herein, a unidirectional Janus membrane composed of two functional layers is prepared by sequential electrospinning. The outer layer is designed as random polycaprolactone fibers incorporated with tannic acid/Fe3+ particles to prevent tissue adhesion, while the inner layer is designed as oriented gelatin fibers to promote tissue repair. Hydrogen bonding was employed to act as a barrier for preventing the diffusion of the tannic acid to the inner side, and thus the release of tannic acid occurs in a unidirectional manner. As a result, asymmetric biological performances of the Janus membrane are achieved. The outer face can provide anti‐inflammatory capability to the membrane and inhibit the viability of fibroblasts, while the inner face can promote the proliferation and differentiation of tendon stem cells. Tendon injured model confirms the prominent inflammation modulation, adhesion prevention, and repair promotion capabilities of the Janus membrane in vivo. This study provides a new strategy to develop advanced functional barrier membranes for postoperative adhesion prevention and internal tissue repair promotion.

109. Comparing the Postoperative Adhesion Prevention Effectiveness of Collagen-glycosaminoglycan (GAG), Hyaluronic Acid (HA), and Pentamidine Using a Turkey In Vivo Model

109. Comparing the Postoperative Adhesion Prevention Effectiveness of Collagen-glycosaminoglycan (GAG), Hyaluronic Acid (HA), and Pentamidine Using a Turkey In Vivo Model