Neutrophil Extracellular Traps: A Crucial Factor in Post-Surgical Abdominal Adhesion Formation.

Post-surgical abdominal adhesions, although poorly understood, are highly prevalent. The molecular processes underlying their formation remain elusive. This review aims to assess the relationship between neutrophil extracellular traps (NETs) and the generation of postoperative peritoneal adhesions and to discuss methods for mitigating peritoneal adhesions. A keyword or medical subject heading (MeSH) search for all original articles and reviews was performed in PubMed and Google Scholar. It included studies assessing peritoneal adhesion reformation after abdominal surgery from 2003 to 2023. After assessing for eligibility, the selected articles were evaluated using the Critical Appraisal Skills Programme checklist for qualitative research. The search yielded 127 full-text articles for assessment of eligibility, of which 7 studies met our criteria and were subjected to a detailed quality review using the Critical Appraisal Skills Programme (CASP) checklist. The selected studies offer a comprehensive analysis of adhesion pathogenesis with a special focus on the role of neutrophil extracellular traps (NETs) in the development of peritoneal adhesions. Current interventional strategies are examined, including the use of mechanical barriers, advances in regenerative medicine, and targeted molecular therapies. In particular, this review emphasizes the potential of NET-targeted interventions as promising strategies to mitigate postoperative adhesion development. Evidence suggests that in addition to their role in innate defense against infections and autoimmune diseases, NETs also play a crucial role in the formation of peritoneal adhesions after surgery. Therefore, therapeutic strategies that target NETs are emerging as significant considerations for researchers. Continued research is vital to fully elucidate the relationship between NETs and post-surgical adhesion formation to develop effective treatments.

Human amnion mesenchymal stem cells promote endometrial repair via paracrine, preferentially than transdifferentiation.

BACKGROUND: Intrauterine adhesion (IUA) is one of the most severe causes of infertility in women of childbearing age with injured endometrium secondary to uterine performance. Stem cell therapy is effective in treating damaged endometrium. The current reports mainly focus on the therapeutic effects of stem cells through paracrine or transdifferentiation, respectively. This study investigates whether paracrine or transdifferentiation occurs preferentially in treating IUA. METHODS: Human amniotic mesenchymal stem cells (hAMSCs) and transformed human endometrial stromal cells (THESCs) induced by transforming growth factor beta (TGF-ß1) were co-cultured in vitro. The mRNA and protein expression levels of Fibronectin (FN), Collagen I, Cytokeratin19 (CK19), E-cadherin (E-cad) and Vimentin were detected by Quantitative real-time polymerase chain reaction (qPCR), Western blotting (WB) and Immunohistochemical staining (IHC). The Sprague-Dawley (SD) rats were used to establish the IUA model. hAMSCs, hAMSCs-conditional medium (hAMSCs-CM), and GFP-labeled hAMSCs were injected into intrauterine, respectively. The fibrotic area of the endometrium was evaluated by Masson staining. The number of endometrium glands was detected by hematoxylin and eosin (H&E). GFP-labeled hAMSCs were traced by immunofluorescence (IF). hAMSCs, combined with PPCNg (hAMSCs/PPCNg), were injected into the vagina, which was compared with intrauterine injection. RESULTS: qPCR and WB revealed that FN and Collagen I levels in IUA-THESCs decreased significantly after co-culturing with hAMSCs. Moreover, CK19, E-cad, and Vimentin expressions in hAMSCs showed no significant difference after co-culture for 2 days. 6 days after co-culture, CK19, E-cad and Vimentin expressions in hAMSCs were significantly changed. Histological assays showed increased endometrial glands and a remarkable decrease in the fibrotic area in the hAMSCs and hAMSCs-CM groups. However, these changes were not statistically different between the two groups. In vivo, fluorescence imaging revealed that GFP-hAMSCs were localized in the endometrial stroma and gradually underwent apoptosis. The effect of hAMSCs by vaginal injection was comparable to that by intrauterine injection assessed by H&E staining, MASSON staining and IHC. CONCLUSIONS: Our data demonstrated that hAMSCs promoted endometrial repair via paracrine, preferentially than transdifferentiation.

IUA is the crucial cause of infertility in women of childbearing age, and no satisfactory treatment measures have been found in the clinic. hAMSCs can effectively treat intrauterine adhesions through paracrine and transdifferentiation mechanisms. This study confirmed in vitro and in vivo that amniotic mesenchymal stem cells preferentially inhibited endometrial fibrosis and promoted epithelial repair through paracrine, thus effectively treating intrauterine adhesions. The level of fibrosis marker proteins in IUA-THESCs decreased significantly after co-culturing with hAMSCs for 2 days in vitro. However, the level of epithelial marker proteins in hAMSCs increased significantly, requiring at least 6 days of co-culture. hAMSCs-CM had the same efficacy as hAMSCs in inhibiting fibrosis and promoting endometrial repair in IUA rats, supporting the idea that hAMSCs promoted endometrial remodeling through paracrine in vivo. In addition, GFP-labeled hAMSCs continuously colonized the endometrial stroma instead of the epithelium and gradually underwent apoptosis. These findings prove that hAMSCs ameliorate endometrial fibrosis of IUA via paracrine, preferentially than transdifferentiation, providing the latest insights into the precision treatment of IUA with hAMSCs and a theoretical basis for promoting the "cell-free therapy" of MSCs.

Semaglutide May Ameliorate Fibrosis and Inhibit Epithelial-Mesenchymal Transition in Intrauterine Adhesion Models.

The purpose of this study was to explore the effect of Semaglutide on intrauterine adhesions and discover new drugs for such adhesions. In this study, the cell model was simulated by TGF-ß1-induced human endometrial epithelial cells, and the animal model was established through mechanical curettage and inflammatory stimulation. After co-culturing with TGF-ß1 with or without different concentrations of Semaglutide for 48 h, cells were collected for RT-qPCR and Western blotting analyses. Three doses were subcutaneously injected into experimental mice once a day for two weeks, while the control group received sterile ddH2O. The serum and uterine tissues of the mice were collected. HE and Masson staining were used for the uterine histomorphological and pathological analyses. RT-qPCR and Western blotting were used for mRNA and protein expression analyses. Serum indicators were detected using ELISA kits. The results showed that Semaglutide significantly reduced the mRNA levels of fibrosis indicators ACTA2, COL1A1, and FN and inflammatory indicators TNF-α, IL-6, and NF-κB in the two models. Semaglutide improved endometrium morphology, increased the number of endometrial glands, and reduced collagen deposition in IUA mice. The results also showed that Semaglutide could inhibit vimentin, E-Cadherin, and N-Cadherin in the two models. In summary, Semaglutide can ameliorate fibrosis and inflammation of intrauterine adhesions as well as inhibit epithelial-mesenchymal transition in IUA models.

The effect of papaverine on tendon healing and adhesion in rats following Achilles tendon repair.

OBJECTIVES: The study aimed to examine the histopathological and biomechanical effects of papaverine administered intraperitoneally and locally on Achilles tendon healing in a rat model. MATERIALS AND METHODS: Forty-eight adult male Sprague-Dawley rats (range, 300 to 400 g) were used in this study conducted between October and November 2022. The rats were divided into three groups, with each group further subdivided into two for sacrifice on either the 15th (early period) or 30th (late period) day after surgery. The first (control) group received no treatment following Achilles tendon repair, while papaverine was intraperitoneally administered every other day for 10 days in the second group and locally in the third group after surgery. On the 15th and 30th days, the rats were sacrificed, and their Achilles tendons were subjected to biomechanical testing and histopathological evaluation. RESULTS: Histopathologically, there were no significant differences among the groups on the 15th day. However, on the 30th day, the locally applied papaverine group exhibited superior histopathological outcomes compared to the control group (p<0.05). Concerning the highest tensile strength values before rupture, the biomechanical assessment showed that the group receiving local papaverine treatment in the early period and both the group with systemic papaverine treatment and the one with local papaverine treatment in the late period displayed a statistically significant advantage compared to the control group (p<0.05). CONCLUSION: Locally administered papaverine has positive biomechanical effects in the early period and exhibits a positive correlation both histopathologically and biomechanically in the late period. Novel therapeutic options may be provided for patients through these findings.

Comparison of the effect of Everolimus, Prednisolone, and a combination of both on experimentally induced peritoneal adhesions in rats.

Postoperative intra-abdominal adhesions represent a significant post-surgical problem. Its complications can cause a considerable clinical and cost burden. Herein, our study aimed to investigate the effect of Everolimus on peritoneal adhesion formation after inducing adhesions in rats. In this experimental study, adhesion bands were induced by intraperitoneal injection of 3 ml of 10% sterile talc solution in 64 male albino rats. The first group served as the control group. The second one received oral Prednisolone (1 mg/kg/day), the third received Everolimus (0.1 mg/kg/day), and group four received both drugs with similar dosages for four consecutive weeks. The formation of adhesion bands was qualitatively graded according to the Nair classification. The rats in the control group had extensive adhesions between the abdominal wall and the organs. Regarding substantial adhesion formation, 50% (8/16) of animals in the control group had substantial adhesions, while this rate in the groups receiving Prednisolone, Everolimus, and combination treatment was 31%, 31%, and 31%, respectively. Also, 68.75% (5/11) of the Prednisolone recipients had insubstantial adhesions, the same as Everolimus recipients, while in the combination group, 66.66% (10/15) rats had insubstantial adhesions. Everolimus demonstrated satisfactory results in reducing the rates of induced peritoneal adhesion in an experimental model, similar to Prednisolone and superior to a combination regime.

Repurposing of Angiotensin-converting-enzyme Inhibitor on Prevention of Post-surgical Tendon Adhesion.

BACKGROUND: Formation of adhesion bands is a frequent clinical complication after tendon injury or surgery with limited treatment options. This study investigates the repurposing of Angiotensin-Converting-Enzyme Inhibitor (ACEI) in attenuating post-operative tendon-sheath adhesion bands in an Achilles tendon rat model. METHODS: Structural, mechanical, histological, and biochemical characteristics of the Achilles tendons were compared in the presence and absence of oral ACEI (enalapril) using the Achilles tendon adhesion (TA) model in rats. Inflammation and total fibrosis of tendon tissues were compared between groups using molecular investigations along with macroscopic and histological scoring methods. RESULTS: ACEI significantly alleviated the severity, length, and density of Achilles TAs. Moreover, histopathological changes, recruitment of inflammatory cells, and inflammation were significantly decreased in post-operative tissue samples as quantified with the Moran scoring model. We showed that ACEI treatment elicits a potent anti-fibrotic effect on tendon tissue samples, as illustrated by decreasing the severity and extent of the formed fibrotic tissue and collagen accumulation at the site of surgery when scored either by Tang or Ishiyama grading systems. The H&E staining showed no histopathological changes or damage to the principal organs. CONCLUSION: Our results showed that ACEI is a safe and effective therapeutic candidate with potent immunomodulatory and anti-fibrotic features to alleviate surgery-induced development of fibrotic adhesive tissue. However, its efficacy needs to be further validated in clinical studies.

Phacoemulsification combined with goniosynechialysis versus phacoemulsification alone for patients with primary angle­closure disease: A meta-analysis.

This meta-analysis aims to systematically compare the efficacy between phacoemulsification (PE) combined with goniosynechialysis (GSL) and PE alone for primary angle-closure disease (PACD) patients. All the data were searched from the PubMed, EMBASE and the Cochrane Library. The Cochrane Handbook was used to evaluate the quality of the included studies. Additionally, this meta-analysis was performed by using the Revman 5.4 software. Nine randomized controlled trials (RCTs) were included in this study. Compared with PE alone group, PE+GSL could result significant reduction in the IOP (MD, 1.81; p = 0.002). In the instrumental subgroup, also more reduction of IOP was shown in the PE+GSL group (MD, 2.11; p = 0.02). In the viscogonioplasty (VGP) subgroup, there was not no statistical difference between PE alone group and PE+GSL group (MD, 1.53; p = 0.11). Also, more reduction of peripheral anterior synechiae (PAS) was shown in the PE+GSL group (MD,59.15; p<0.00001). For the change in angle open distance (AOD)500, AOD 750, trabecular-iris space (TISA)500, number of glaucoma medications and best corrected visual acuity (BCVA), there was no difference between two groups (p = 0.25, 0.35, 0.17, 0.56, 0.08). For TISA 750, more improvement was shown in the PE+GSL group (p<0.00001). Instrumental separation had better effect on lowering IOP when it combined with PE. Both instrumental separation and VGP could reduce postoperative PAS. The operation of GSL has no obvious effect on postoperative vision.

Investigation of anti-adhesion ability of 8-arm PEGNHS-modified porcine pericardium.

In post-adhesion surgery, there is a clinical need for anti-adhesion membranes specifically designed for the liver, given the limited efficacy of current commercial products. To address this demand, we present a membrane suitable for liver surgery applications, fabricated through the modification of decellularized porcine pericardium with 20 KDa hexaglycerol octa (succinimidyloxyglutaryl) polyoxyethylene (8-arm PEGNHS). We also developed an optimized modification procedure to produce a high-performance anti-adhesion barrier. The modified membrane significantly inhibited fibroblast cell adherence while maintaining minimal levels of inflammation. By optimizing the modification ratio, we successfully controlled post-adhesion formation. Notably, the 8-arm PEG-modified pericardium with a molar ratio of 5 exhibited the ability to effectively prevent post-adhesion formation on the liver compared to both the control and Seprafilm®, with a low adhesion score of 0.5 out of 3.0. Histological analysis further confirmed its potential for easy separation. Furthermore, the membrane demonstrated regenerative capabilities, as evidenced by the proliferation of mesothelial cells on its surface, endowing anti-adhesion properties between the abdominal wall and liver. These findings highlight the membrane's potential as a reliable barrier for repeated liver resection procedures that require the removal of the membrane multiple times.

Novel therapeutic targets, including IGFBP3, of umbilical cord mesenchymal stem-cell-conditioned medium in intrauterine adhesion.

Mesenchymal stem cells play important roles in repairing injured endometrium. However, the molecular targets and potential mechanism of the endometrial recipient cells for stem cell therapy in intrauterine adhesion (IUA) are poorly understood. In this study, umbilical cord mesenchymal stem-cell-conditioned medium (UCMSCs-CM) produced positive effects on a Transforming growth factor beta (TGF-ß) induced IUA cell model. RNA-sequencing was performed on clinical IUA tissues, and the top 40 upregulated and top 20 downregulated mRNAs were selected and verified using high-throughput (HT) qPCR in both tissues and cell models. Based on a bioinformatic analysis of RNA-sequencing and HT-qPCR results, 11 mRNAs were uncovered to be the intervention targets of UCMSCs-CM on IUA endometrium cell models. Among them, IGFBP3 was striking as a key pathogenic gene and a potential diagnostic marker of IUA, which exhibited the area under the curve (AUC), sensitivity, specificity were 0.924, 93.1% and 80.6%, respectively in 60 endometrial tissues. The silencing of IGFBP3 exerted positive effects on the IUA cell model through partially upregulating MMP1 and KLF2. In conclusion, RNA-sequencing combined with HT qPCR based on clinical tissues and IUA cell models were used in IUA research and our results may provide some scientific ideas for the diagnosis and treatment of IUA.

Injectable Multifunctional Composite Hydrogel as a Combination Therapy for Preventing Postsurgical Adhesion.

Postsurgical adhesion (PA) is a common and serious postoperative complication that affects millions of patients worldwide. However, current commercial barrier materials are insufficient to inhibit diverse pathological factors during PA formation, and thus, highly bioactive materials are needed. Here, this work designs an injectable multifunctional composite hydrogel that can serve as a combination therapy for preventing PA. In brief, this work reveals that multiple pathological events, such as chronic inflammatory and fibrotic processes, contribute to adhesion formation in vivo, and such processes can not be attenuated by barrier material (e.g., hydrogel) alone treatments. To solve this limitation, this work designs a composite hydrogel made of the cationic self-assembling peptide KLD2R and TGF-ß receptor inhibitor (TGF-ßRi)-loaded mesenchymal stem cell-derived nanovesicles (MSC-NVs). The resulting composite hydrogel displays multiple functions, including physical separation of the injured tissue areas, antibacterial effects, and local delivery and sustained release of anti-inflammatory MSC-NVs and antifibrotic TGF-ßRi. As a result, this composite hydrogel effectively inhibited local inflammation, fibrosis and adhesion formation in vivo. Moreover, the hydrogel also exhibits good biocompatibility and biodegradability in vivo. Together, the results highlight that this "all-in-one" composite hydrogel strategy may provide insights into designing advanced therapies for many types of tissue injury.

Photobiomodulation therapy at 632 nm wavelength ameliorates intrauterine adhesion via activation of cAMP/PKA/CREB pathway.

Intrauterine adhesion (IUA), a major cause of uterine infertility, is pathologically characterized by endometrial fibrosis. Current treatments for IUA have poor efficacy with high recurrence rate, and restoring uterine functions is difficult. We aimed to determine the therapeutic efficacy of photobiomodulation (PBM) therapy on IUA and elucidate its underlying mechanisms. A rat IUA model was established via mechanical injury, and PBM was applied intrauterinely. The uterine structure and function were evaluated using ultrasonography, histology, and fertility tests. PBM therapy induced a thicker, more intact, and less fibrotic endometrium. PBM also partly recovered endometrial receptivity and fertility in IUA rats. A cellular fibrosis model was then established with human endometrial stromal cells (ESCs) cultured in the presence of TGF-ß1. PBM alleviated TGF-ß1-induced fibrosis and triggered cAMP/PKA/CREB signaling in ESCs. Pretreatment with the inhibitors targeting this pathway weakened PBM's protective efficacy in the IUA rats and ESCs. Therefore, we conclude that PBM improved endometrial fibrosis and fertility via activating cAMP/PKA/CREB signaling in IUA uterus. This study sheds more lights on the efficacy of PBM as a potential treatment for IUA.

Low-adhesion and low-swelling hydrogel based on alginate and carbonated water to prevent temporary dilation of wound sites.

Hydrogel-based wound dressings have been developed for rapid wound healing; however, their adhesive properties have not been adequately investigated. Excessive adhesion to the skin causes wound expansion and pain when hydrogels absorb exudates and swell at wound sites. Herein, we developed a low-adhesion and low-swelling hydrogel dressing using alginate, which is non-adhesive to cells and skin tissue, CaCO3, and carbonated water. The alginate/CaCO3 solution rapidly formed a hydrogel upon the addition of carbonated water, and the CO2 in the hydrogel diffused into the atmosphere, preventing acidification and obtaining a pH value suitable for wound healing. Remarkably, the skin adhesion and swelling of the hydrogel were 11.9- to 16.5-fold and 1.9-fold lower, respectively, than those of clinical low-adhesion hydrogel dressings. In vivo wound-healing tests in mice demonstrated its therapeutic efficacy, and the prepared hydrogel prevented temporary wound dilation during early healing. These results illustrate the importance of controlling skin adhesion and swelling in wound dressings and demonstrate the potential clinical applications of this wound-friendly hydrogel dressing.

Repair of a chronic myometrial defect with successful pregnancy outcome.

OBJECTIVE: To surgically demonstrate preconceptional laparoscopic repair of a chronic myometrial defect with mesh reinforcement, resulting in a successful pregnancy outcome. DESIGN: Video case report. The Institutional Ethical Committee was consulted, and the requirement for approval was waived because the video describes a modified surgical technique. The patient included in this video gave consent for publication of the video and posting of the video online, including on social media, the journal website, scientific literature websites (such as PubMed, ScienceDirect, Scopus, and others), and other applicable sites. SETTING: A referral advanced gynecological endoscopy center. PATIENT: A 27-year-old woman (P0A1) was diagnosed with myomas during pregnancy, resulting in miscarriage at 22 weeks. Laparotomy and myomectomy were performed 2 months later, and three 8-cm myomas were removed. The endometrial cavity opened posteriorly during surgery, and retained products of conceptions were removed. Periconceptional imaging done after two years showed few intramural myomas and a deficient myometrium in the posterior fundal region. Laparoscopy revealed a defect in the posterior fundal aspect of the uterus with leakage of dye, which was converted to laparotomy and myomectomy with the repair of the myometrial defect. After 1 year, follow-up magnetic resonance imaging showed thinned-out posterior myometrium with a focal area of absent myometrium in the midline and endometrial prolapse. The patient was advised on surrogacy, but she wanted to repair the defect again and try for pregnancy, so she was referred to our center. With the background of a few case reports using mesh to reinforce myometrial repair (1, 2), we counseled the patient about the myometrial repair with the additional use of mesh as an off-label use. INTERVENTION: The risk of uterine rupture after myomectomy is rare (<1%) (3), but it is a severe complication. High-risk cases, like significant myometrial defects or previous ruptures, may require surgical correction. Native repair may not achieve optimal results in all cases. Alternative approaches, like the additional use of mesh or biological materials, have been reported (4). In this case, we demonstrate the use of dual mesh for scar repair. Synthetic mesh over the uterus is used in laparoscopic procedures like sacrohysteropexy and cerclage. We used Parietex (Covidien, New Haven, CT, USA) mesh, a composite macroporous polyester mesh usually used for ventral hernia repair. It has an outer hydrophilic, absorbable collagen barrier that reduces adhesion formation. Laparoscopically, after adhesiolysis, a significant defect was demonstrated on the posterior wall of the uterus (Fig. 1). A complete resection of the fibrotic tissue along the edges of the scar defect was done to expose healthy myometrium. Myometrium was repaired in two layers, excluding the endometrium, with a V-Loc (Covidien, Dublin, Ireland) No. 1-0 suture. Parietex mesh was sutured over the repaired posterior myometrium to reinforce it (Fig. 2). MAIN OUTCOME MEASURES: The postoperative myometrial thickness on imaging and pregnancy outcome. RESULTS: Postoperative ultrasound scan after 6 weeks demonstrated restoration of posterior wall myometrial thickness of 14 mm. The patient was conceived through in vitro fertilization techniques 4 months after surgery. Antenatal follow-up was uneventful except for suspicion of posterior placenta accreta. She underwent an elective cesarean section with uterine artery embolization at 34 weeks and delivered a healthy infant weighing 1,950 g. Placental removal was uneventful. On inspection, the posterior surface of the uterus was intact without dehiscence, meshing in situ with minimal adhesions (Fig. 3). CONCLUSION: Myometrial scar defects can cause potential obstetric complications. Native repair of scar defects may not achieve optimal results, as in our case. Mesh repair of myomectomy scar defects can be used as an alternative approach, as exemplified in this case. However, further studies are required to establish the safety and efficacy of this approach.

A cost-effectiveness analysis of intrauterine spacers used to prevent the formation of intrauterine adhesions following endometrial cavity surgery.

AIM: To assess, from a United States (US) payer's perspective, the cost-effectiveness of gels designed to separate the endometrial surfaces (intrauterine spacers) placed following intrauterine surgery. MATERIALS AND METHODS: A decision tree model was developed to estimate the cost-effectiveness of intrauterine spacers used to facilitate endometrial repair and prevent the formation (primary prevention) and reformation (secondary prevention) of intrauterine adhesions (IUAs) and associated pregnancy- and birth-related adverse outcomes. Event rates and costs were extrapolated from data available in the existing literature. Sensitivity analyses were conducted to corroborate the base case results. RESULTS: In this model, using intrauterine spacers for adhesion prevention led to net cost savings for US payers of $2,905 per patient over a 3.5-year time horizon. These savings were driven by the direct benefit of preventing procedures associated with IUA formation ($2,162 net savings) and the indirect benefit of preventing pregnancy-related complications often associated with IUA formation ($3,002). These factors offset the incremental cost of intrauterine spacer use of $1,539 based on an assumed price of $1,800 and the related increase in normal deliveries of $931. Model outcomes were sensitive to the probability of preterm and normal deliveries. Budget impact analyses show overall cost savings of $19.96 per initial member within a US healthcare plan, translating to $20 million over a 5-year time horizon for a one-million-member plan. LIMITATIONS: There are no available data on the effects of intrauterine spacers or IUAs on patients' quality of life. Resultingly, the model could not evaluate patients' utility related to treatment with or without intrauterine spacers and instead focused on costs and events avoided. CONCLUSION: This analysis robustly demonstrated that intrauterine spacers would be cost-saving to healthcare payers, including both per-patient and per-plan member, through a reduction in IUAs and improvements to patients' pregnancy-related outcomes.

Every year, women in the United States (US) undergo surgery to treat intrauterine abnormalities to maintain or improve the uterus' ability to support fetal development and result in a term delivery. Despite the benefits of these procedures, damage caused to the endometrium (uterine lining) is associated with a risk of adherence of the endometrial cavity surfaces with scar tissue known as intrauterine adhesions (IUAs).Damage to the endometrium and the resulting IUAs may be associated with infertility, light or absent menstruation, pregnancy loss, and other pregnancy-related complications. Treating these conditions within the US healthcare system consumes resources and adds costs for healthcare payers (public and private insurance providers).To facilitate endometrial repair and to reduce or prevent IUAs, researchers have developed materials to place within the endometrial cavity following surgery to separate the endometrial surfaces during the early healing period. These intrauterine "spacers" are intended to improve patients' subsequent clinical outcomes and save money for healthcare payers. It is unknown whether these improved clinical outcomes offset the cost of the routine use of spacers following "at-risk" procedures that involve the endometrial cavity.We developed a model designed to determine the cost-effectiveness of an intrauterine spacer by quantifying improvements in clinical outcomes and the resultant cost savings for patients undergoing uterine surgeries with or without spacers. Our model predicted that routinely using such spacers following at-risk procedures would improve patient outcomes and reduce costs to US payers.

Nano-biomaterial Fibrinogen/P(LLA-CL) for prevention of intrauterine adhesion and restoration of fertility.

Endometrial damage resulting from surgical procedures is a significant cause of intrauterine adhesion, thin endometrium, and subsequent miscarriage and infertility. Unfortunately, there is currently no effective clinical solution to promote endometrial regeneration after severe injury. In this study, we combined fibrinogen (Fg) and P(LLA-CL) by electrostatic spinning to form a stable nano-biomaterial Fg/P(LLA-CL), which can promote endometrial regeneration. After inducing physical injury to rat endometrium, we found that Fg/P(LLA-CL) membranes placed in the uterine cavities increased endometrial thickness and the number of glands after injury, while reducing the area of endometrial fibrosis. In addition, Fg/P(LLA-CL) increased neovascularization and decreased COL1A1 deposition. The expression of TGF-ß1, a cytokine that promotes fibrosis, was down-regulated in the early stage of injury. Finally, fertility assays confirmed that Fg/P(LLA-CL) improved the pregnancy rate in rats with endometrial injury, and its safety was verified by blood tests and pathological examination of heart, liver, spleen, lung, and kidney. Therefore, Fg/P(LLA-CL) shows great potential as a safe and nontoxic biomaterial for endometrial regeneration, ultimately improving pregnancy outcomes in patients with intrauterine adhesion.

Characterization of Nerve Damage After an Injury to the Adjacent Soft Tissue: A Pilot Animal Study.

Traumatic injuries may result in the formation of soft tissue adhesions between peripheral nerves and surrounding soft tissue. These soft tissue adhesions lead to compression and ischemic stress within fascicles due to nonpliability of adhered scar tissue, and nerve tension due to loss of nerve gliding from scar tethering. These changes in the soft tissue bed surrounding the nerve may result in axon degeneration and neuroma-in-continuity. Preclinical models that simulate clinically relevant levels of scar in the nerve environment may be impactful to the development of surgical techniques and treatments to prevent adhesions. This study presents the results of a rodent model with an induced indirect nerve injury by (1) thermal insult to the soft tissue bed surrounding the nerve and (2) air-drying the surrounding soft tissue bed of the nerve. Our findings suggest that inducing an injury of the soft tissue bed results in increased intraneural scar and extraneural adhesions to the nerve compared to a sham procedure. Thermal induced injuries showed more macrophages and changes in nerve health compared to air-dried induced injuries. The changes in the nerves of the induced injury groups, specifically the thermal injury group, may be meaningful for evaluating treatments for nontransected nerve injuries.

[Histological changes in intraperitoneal onlay mesh (IPOM) with synthetic and biological meshes. Results of the chronic experiment]. / Gistologicheskie izmeneniya pri intraperitoneal'noi plastike (IPOM) sinteticheskimi i biologicheskimi endoprotezami. Rezul'taty khronicheskogo eksperimenta.

OBJECTIVE: The objective of the study was to analyze histological changes in the site of the meshes FTOREX, FTOREX coated with carboxymethylcellulose, Ventralight ST, Symbotex, REPEREN-16-2 and decellularized porcine peritoneum on the parietal peritoneum of the pig. MATERIAL AND METHODS: At laparoscopy, 6 different meshes were placed intraperitoneally in each of the 3 pigs. After 90 days, the animals were taken out of the experiment. After staining with hematoxylin and eosin, quantitative morphometry and counting the number of vessels and cells in the interstitium in the areas of the mesh and peritoneum were performed. An immunohistochemical study with an antibody to pancytokeratins assessed the state of the initial peritoneum and neoperitoneum. RESULTS: According to morphological characteristics, the meshes were divided into 3 groups: 1) with fluoropolymer coating FTOREX, 2) Ventralight ST and Symbotex, 3) REPEREN and decellularized peritoneum. In group 1, the surface area of the mesh threads was optimal in terms of the arrangement and arrangement of the threads relative to each other. This contributed to the formation of a relatively dense fibrous framework and a place to preserve the underlying peritoneum involved in the formation of the neoperitoneum. Despite the smallest surface area of the threads, in group 3, the greatest fibroblastic reaction was noted. Inflammatory changes were the least pronounced in group 1. They were the greatest in group 3, where there was a pronounced leukocyte reaction, combined with the processes of metaplasia, the development of fibrinoid necrosis, and the progression of the secondary inflammatory process. In group 1, the optimal ratio of newly formed vessels was noted, in group 2 - veins prevailed over arteries, in group 3 - the number of vessels was minimal. Immunohistochemical study showed that in group 1, mesothelial cells covered almost the entire surface of the implant, and there were also areas of preserved basic peritoneum. In group 2, mesothelium also covered most of the surface of the meshes, but the underlying peritoneum was absent. In group 3, on the contrary, a significant number of extended areas not covered with mesothelium were revealed. CONCLUSION: The conducted morphological and morphometric study showed that the most balanced ratio of the components of the newly formed fibrous tissue and blood vessels is observed when using implants with a fluoropolymer coating FTOREX. At the same time, the remaining basic peritoneum actively participated in the formation of the neoperitoneum. The Ventralight ST and Symbotex meshes also contributed to the formation of a full-fledged fibrous tissue and adequate vascular proliferation, however, they prevented the preservation of the underlying peritoneum, which practically excluded its participation in the formation of the neoperitoneum. The REPEREN mesh and decellularized porcine peritoneum led to the least balanced cell and vascular proliferation and the greatest fibroplastic reaction, which could further negatively affect the state of the formed scar.

Ferroptosis contributes to endometrial fibrosis in intrauterine adhesions.

Intrauterine adhesions (IUA), characterized by endometrial fibrosis, is a challenging clinical issue in reproductive medicine. We previously demonstrated that epithelial-mesenchymal transition (EMT) and fibrosis of endometrial stromal cells (HESCs) played a vital role in the development of IUA, but the precise pathogenesis remains elucidated. Ferroptosis has now been recognized as a unique form of oxidative cell death, but whether it is involved in endometrial fibrosis remains unknown. In the present study, we performed an RNA-seq of the endometria from 4 severe IUA patients and 4 normal controls. Enrichment analysis and protein-protein interactions (PPIs) network analysis of differentially expressed genes (DEGs) were conducted. Immunohistochemistry was used to assess ferroptosis levels and cellular localization. The potential role of ferroptosis for IUA was investigated by in vitro and in vivo experiments. Here, we demonstrated that ferroptosis load is increased in IUA endometria. In vitro experiments showed that erastin-induced ferroptosis promoted EMT and fibrosis in endometrial epithelial cells (P < 0.05), but did not lead to pro-fibrotic differentiation in endometrial stromal cells (HESCs). Cell co-culture experiments showed that erastin-stimulated epithelial cell supernatants promoted fibrosis in HESCs (P < 0.05). In vivo experiments suggested that elevation of ferroptosis level in mice by erastin led to mild endometrial EMT and fibrosis. Meanwhile, the ferroptosis inhibitor Fer-1 significantly ameliorated endometrial fibrosis in a dual-injury IUA murine model. Overall, our findings revealed that ferroptosis may serve as a potential therapeutic target for endometrial fibrosis in IUA.

Construction and evaluation of intrauterine adhesion model in rats by different methods of mechanical injury.

PURPOSE: The study aimed to establish a stable and effective animal model for the experimental study of intrauterine adhesion (IUA) by evaluating various mechanical injury methods. METHODS: A total of 140 female rats were divided into four groups according to the extent and area of endometrial injury: group A (excision area: 2.0 × 0.5 cm2), group B (excision area: 2.0 × 0.25 cm2), group C (endometrial curettage) and group D (sham operation). On the 3rd, 7th, 15th and 30th day after the operation, the tissue samples of each group were collected, and the uterine cavity stenosis and histological changes were recorded by HE and Masson staining. Immunohistochemistry of CD31 was applied to visualize microvessel density (MVD). The pregnancy rate and the number of gestational sacs were used to evaluate the reproductive outcome. RESULTS: The results showed that endometrium injured by small-area endometrial excision or simple curettage could be repaired. The ratio of fibrosis in groups A and B was higher than that in groups C and group D 30 days after modeling (P < 0.001). The number of endometrial glands and MVD in group A was significantly lower than those in groups B, C and D (P < 0.05). The pregnancy rate in group A was 20%, which was lower than that in groups B (33.3%), C (89%) and D (100%) (P < 0.05). CONCLUSION: Full-thickness endometrial excision has a high rate of success in constructing stable and effective IUA models in rats.

M2 Macrophage Membrane-Mediated Biomimetic-Nanoparticle Carrying COX-siRNA Targeted Delivery for Prevention of Tendon Adhesions by Inhibiting Inflammation.

Tendon adhesion is the most common outcome of tendon or tendon-to-bone healing after injury. Our group developed a hydrogel-nanoparticle sustained-release system previously to inhibit cyclooxygenases (COXs) expression and consequently prevent tendon adhesion and achieved satisfactory results. However, effective treatment of multiple tendon adhesions is always a challenge in research on the prevention of tendon adhesion. In the present study, an M2M@PLGA/COX-siRNA delivery system is successfully constructed using the cell membranes of M2 macrophages and poly (lactic-co-glycolic acid) (PLGA) nanoparticles. Targeting properties and therapeutic effects are observed in mice or rat models of flexor digitorum longus (FDL) tendon injury combined with rotator cuff injury. The results showed that the M2M@PLGA/COX-siRNA delivery system has low toxicity and remarkable targeting properties to the injured areas. Treatment with the M2M@PLGA/COX-siRNA delivery system reduced the inflammatory reaction and significantly improved tendon adhesion in both the FDL tendon and rotator cuff tissues. These findings indicate that the M2M@PLGA delivery system can provide an effective biological strategy for preventing multiple tendon adhesions.