The effect of Interceed for reducing adhesion as a middle ear packing agent: an experimental study

Interceed combined with bone marrow mesenchymal stem cells improves endometrial receptivity of intrauterine adhesion

Background

This study aimed to investigate the impact of intrauterine adhesions (IUA) therapy and endometrial receptivity by implanting autologous bone marrow mesenchymal stem cells (BMSCs) into the Interceed and subsequently placing them in the uterine cavity of rats.

Methods

Fifty rats were divided into 5 groups according to the random number table method (10 rats in each group). Following the development of the IUA model through mechanical injury, the animals were categorized into different treatment groups: the IUA model (intrauterine perfusion of saline), Interceed therapy (intrauterine placement of Interceed), BMSCs therapy (intrauterine perfusion of BMSCs), BMSCs + Interceed therapy (intrauterine placement of BMSCs + Interceed), and a control group (intrauterine perfusion of saline). The Hematoxylin-eosin (HE) staining technique was employed to identify and assess the pathological alterations in the endometrium. Additionally, it facilitated the quantification of endometrial glands and the determination of endometrial thickness. Masson staining was used to detect fibrosis in rat uterus. The number of microvascular density (MVD) was detected by immunohistochemistry (IHC). Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot were used to detect the levels of leukemia inhibitory factor (LIF), integrin ανβ3, and vascular endothelial growth factor (VEGF) in uterine tissue. Male and female rats were combined in cages for reproductive and conception evaluation.

Results

In comparison to the control, the number of endometrial glands in the IUA model was significantly reduced, and the degree of endometrial thinning and fibrosis was significantly increased (p < 0.05). Compared with the IUA model, the number of endometrial glands did not exhibit any significant alterations in endometrial thickness and MVD number. The expressions of LIF, integrin ανβ3, and VEGF in the uterine tissue were not significantly improved with Interceed therapy, resulting in no significant improvement in the pregnancy rate (p > 0.05). The number of endometrial glands, endometrial thickness, and MVD in the BMSCs therapy group were significantly increased. Moreover, the expressions of LIF, integrin ανβ3, and VEGF in uterine tissue exhibited a significant increase, leading to a comparatively higher pregnancy rate (p < 0.05). In the BMSCs + Interceed therapy group, the number of endometrial glands, endometrial thickness, and MVD were significantly increased, and the expressions of LIF, integrin ανβ3, and VEGF in uterine tissue were significantly increased as well, along with a corresponding rise in the pregnancy rate (p < 0.05).

Conclusion

The intrauterine placement of Interceed combined with BMSCs in IUA rats can thicken the damaged endometrium, increase the number of glands, promote endometrial angiogenesis, improve endometrial receptivity, and increase the rate of pregnancy in IUA rats.

Cyclical endometrial repair and regeneration: Molecular mechanisms, diseases, and therapeutic interventions

The endometrium is a unique human tissue with an extraordinary ability to undergo a hormone-regulated cycle encompassing shedding, bleeding, scarless repair, and regeneration throughout the female reproductive cycle. The cyclical repair and regeneration of the endometrium manifest as changes in endometrial epithelialization, glandular regeneration, and vascularization. The mechanisms encompass inflammation, coagulation, and fibrinolytic system balance. However, specific conditions such as endometriosis or TCRA treatment can disrupt the process of cyclical endometrial repair and regeneration. There is uncertainty about traditional clinical treatments' efficacy and side effects, and finding new therapeutic interventions is essential. Researchers have made substantial progress in the perspective of regenerative medicine toward maintaining cyclical endometrial repair and regeneration in recent years. Such progress encompasses the integration of biomaterials, tissue-engineered scaffolds, stem cell therapies, and 3D printing. This review analyzes the mechanisms, diseases, and interventions associated with cyclical endometrial repair and regeneration. The review discusses the advantages and disadvantages of the regenerative interventions currently employed in clinical practice. Additionally, it highlights the significant advantages of regenerative medicine in this domain. Finally, we review stem cells and biologics among the available interventions in regenerative medicine, providing insights into future therapeutic strategies.

Polymer materials for prevention of postoperative adhesion

Postoperative adhesion (POA) is a common complication that often occurs after a variety of surgeries, such as plastic surgery, repair operations of abdominal, pelvic, and tendon, and so forth. Moreover, POA leads to chronic abdominal pain, secondary infertility in women, intestinal obstruction, and other severe complications, which significantly reduce the life quality of patients. In order to prevent the formation of POA, a number of strategies have been developed, among which an emerging method is physical barriers consisting of polymer materials. This review highlights the most commonly used natural and synthetic polymer materials in anti-adhesion physical barriers. The specific features of polymer materials are analyzed and compared, and the possible prospect is also predicted.

STATEMENT OF SIGNIFICANCE

Postoperative adhesion (POA) is a serious complication accompanied with various surgeries. Polymer material-based physical barriers have attracted a large amount of attention in POA prevention. The polymer barriers can effectively avoid the formation of fibrous tissues among normal organs by reducing the interconnection of injured tissues. In this review, specific features of the natural and synthetic polymer materials for application in POA prevention were presented, and the possible prospects were predicted. All in all, our work can provide inspiration for researchers to choose proper polymer materials for preclinical and even clinical anti-adhesion studies.

Safety and Efficacy of Chitosan-Dextran Hydrogel in the Middle Ear in an Animal Model

OBJECTIVES

To investigate the efficacy of chitosan-dextran hydrogel (CDH) in preventing postoperative adhesions between the tympanic membrane (TM) and intratympanic structures, and to evaluate its ototoxicity in an animal study.

METHODS

In the first step, ototoxicity was evaluated with 7 male albino guinea pigs (GPs) via auditory brainstem responses (ABR) before and 4 weeks after unilateral intratympanic injection of CDH and saline solution contralaterally. In the second step, 12 GPs underwent bilateral ear surgery. The middle ear (ME) mucosa was abraded, and the cavity was filled with CDH on one side and packed with Gelfoam on the contralateral side. A control group of 6 GPs underwent the same procedure except that no material was applied in the ME. The animals were euthanized at the end of the 7th week, and otomicroscopic findings were noted and the temporal bones harvested for the histologic examination. The findings were scored and compared.

RESULTS

There was no statistically significant difference between the pre- and postoperative ABR thresholds. In the otomicroscopic findings, the most prominent difference between the two groups was the presence of retraction of the TM in the Gelfoam group. The histopathologic findings revealed a higher degree of inflammation in the Gelfoam group compared with the CDH group.

CONCLUSION

This study demonstrated that CDH has no ototoxic effects in GPs. Its use as an ME packing material revealed significantly less TM retraction and inflammatory reaction compared with Gelfoam.

Antifibrotic effect of dexamethasone/alginate-coated silicone sheet in the abraded middle ear mucosa

Silicone sheet is a material which is commonly used in middle ear surgery to prevent the formation of adhesions between the tympanic membrane and the medial bony wall of the middle ear cavity. However, silicone sheet can induce a tight and hard fibrous capsule in the region of the stapes, and this is particularly common in cases of eustachian tube dysfunction. As a result of the fibrous encapsulation around the silicone sheet, postoperative aeration of the stapes can be interrupted causing poor hearing gain. In this study, we performed an in vitro and in vivo evaluation of the antifibrotic effects of a dexamethasone and alginate (Dx/alginate) coating on silicone sheet. The Dx/alginate-coated silicone sheets were fabricated using a plasma-treatment and coating method. The Dx/alginate-coated silicone sheets effectively limited in vitro fibroblast attachment and proliferation due to the controlled release of Dx, which can be modified by manipulation of the alginate coating. For the in-vivo evaluation, guinea pigs (albino, male, weighing 250g) were divided into two groups, with the control group (n=5) implanted with silicone sheet and the test group (n=5) receiving Dx/alginate-coated silicone sheet. Animals were sacrificed 3 weeks after implantation, and histological analysis was performed using hematoxylin and eosin (H&E) and immunohistochemical staining techniques. Dx/alginate-coated silicone sheets showed marked inhibition of fibrosis in both the in vitro and in vivo studies. Silicone sheet that incorporates a Dx/alginate coating can release Dx and inhibit fibrosis in the middle ear. This material could be utilized in middle ear surgery as a means of preserving proper aeration and hearing gain following ossiculoplasty.

Middle ear packing materials: comparison between absorbable hemostatic gelatine sponge and sugarcane biopolymer sponge in rats

Introduction

Several biomaterials can be used in ear surgery to pack the middle ear or support the graft. The absorbable gelatin sponge is the most widely used, but it may produce fibrosis and impair ventilation of the middle ear.

Objective

This experimental study aimed to investigate the inflammatory effects of the sugarcane biopolymer sponge (BP) in the rat middle ear compared with absorbable gelatin sponge (AGS).

Materials and methods

Prospective experimental study design. Thirty adult female Wistar rats were allocated to receive the BP sponge into the right ear and AGS into the left ear. Animals were randomly killed at 4 and 12 weeks post-procedure. Qualitative histological assessments were performed to evaluate the inflammatory reaction in the tympanic bullae.

Results

The BP sponge caused inflammation more intense and persistent than AGS. The BP was not absorbed during the experiment. Fibrosis was observed only in the ears with AGS. There were thickening of the mucosa and neoangiogenesis in the group of AGS.

Conclusion

Despite inflammation, the BP sponge produced less fibrosis and neoangiogenesis compared to AGS. The sponge BP appeared to be a non-absorbable biomaterial in the middle ear.

Effect of anti-adhesion barrier solution containing ciprofloxacin-hydrocortisone on abraded mucosa with otitis media

OBJECTIVE

No study to date has assessed the anti-adhesive effect of new middle ear (ME) packing agents in. This study compared the anti-inflammatory and anti-adhesive effect of antibiotic-steroid containing packing agents in abraded mucosa of the ME inflammation.

MATERIALS AND METHODS

Transbullar injection of a saline suspension of Pseudomonas aeruginosa lipopolysaccharide (LPS) induced otitis media. ME mucosa of guinea pigs was abraded using a pick 30 min after LPS inoculation. The animals were divided into four groups of 10 guinea pigs each. In group A, ME cavity was preserved without any packing. In group B, ME cavity was packed with soluble hyaluronic acid-carboxymethyl cellulose (HA-CMC). In group C, the ME cavity was packed with soluble HA-CMC. In group D, the ME cavity was packed with antibiotic-steroid containing soluble HA-CMC. Otoendoscopic examination, auditory brainstem responses (ABRs), and radiographic examination using computerized tomography (CT) were performed at 2 weeks post-surgery. Histopathological evaluation for ME mucosa was performed by light microscopy (LM) and scanning electron microscopy (SEM).

RESULTS

Otoendoscopic findings and CT findings revealed that group D showed the best recovery of aeration in the ME compared to other groups. Recovery of ABRs threshold was significantly attenuated in group D. In LM and SEM findings, group D showed normalized mucosal thickening compared to other groups.

CONCLUSION

ME packing by antibiotic-steroid containing soluble HA-CMC may be useful in the abraded mucosa of the ME inflammation.

Effects of middle ear packing with collagen polyvinylpyrrolidone and hyaluronic acid in guinea pigs

OBJECTIVE

The aim of this study was to evaluate otoscopic and microscopic changes produced on the healthy mucosa of the middle ear (ME) and tympanic membrane (TM) of guinea pigs after packing with a collagen polyvinylpyrrolidone (CPVP) sponge soaked in hyaluronic acid (HA).

MATERIAL AND METHODS

In 24 guinea pigs, myringotomy on the right side was created and the ME was packed as follows: Group I (n = 6): Absorbable gelatin sponge (AGS) soaked in saline solution; Group II (n = 6): AGS sponge soaked in HA, Group III (n = 6): CPVP sponge soaked in saline solution, Group IV (n = 6): CPVP sponge soaked in HA. Four weeks after miringotomy, the ME and TM integrity and residual packing material were evaluated otoscopically. Histologically, we evaluated inflammatory changes on the ME mucosa.

RESULTS

All animals in Groups I and II showed residual packing material (p < .001 ANOVA, TUKEY). Histologically, more inflammation was observed in Groups I, II, and III than in Group IV (p < .001 ANOVA, TUKEY). Group IV showed greater fibroblastic reaction (p < .02, ANOVA, TUKEY) versus other groups.

CONCLUSION

The CPVP sponge soaked in HA used as ME packing material is biocompatible and nontoxic, because it produces minimal inflammatory changes on the healthy mucosa of the ME and TM of guinea pigs. However, more research with injured mucosa is needed to validate its usefulness in otosurgery.

Safety and efficacy of carbomethylcellulose foam in guinea pig middle ear surgery

OBJECTIVE

Carbomethylcellulose (CMC) foam has been widely adopted to promote hemostasis and healing in sinus surgery. There has been interest in the use of CMC in middle ear surgery. The purpose of this study was to evaluate the safety and efficacy of CMC foam for use in middle ear surgery.

STUDY DESIGN

Prospective, controlled.

SETTING

Academic research laboratory.

SUBJECTS AND METHODS

Adult guinea pigs underwent experimental tympanoplasty followed by packing of the middle ear (n = 19 per group) with CMC, hyaluronic acid (HA), or gelatin sponge (GS). Auditory evoked brainstem response testing and otomicroscopy were performed before and serially for eight weeks after surgery. Tympanic membrane healing, hemostasis, and retention of packing material were assessed.

RESULTS

All tympanic membranes treated with CMC healed by week eight. Less postoperative bleeding was observed with CMC than with HA or GS. Surgery elevated auditory thresholds, at least temporarily, in all groups. However, CMC was associated with greater auditory threshold elevation (15-25 dB) at eight weeks across all test frequencies relative to HA or GS (P < 0.01). Residual CMC and scarring were not found in the middle ear, indicating that the hearing loss was sensorineural. No head tilt posturing suggestive of vestibulopathy was seen.

CONCLUSION

CMC was associated with hearing loss and may be ototoxic. Therefore, CMC should not be used in human middle ears given the presence of several nontoxic alternative materials.