Background and purpose: One of the common complications of diabetes is impairment of wound healing. The aim of the present study was to investigate the synergistic effect of hyperbaric oxygen (HBO) ...therapy and decellularized human amniotic membrane (dHAM) in healing of full-thickness diabetic wounds in rats. Materials and methods: In this experimental study, 60 diabetic male rats were randomly divided into four groups (n=15) as follows: untreated diabetic wound, wound treated with HBO, wound treated with dHAM, and wound treated with HBO+dHAM. Sampling was performed after 7, 14, and 21 days following wounding. Assessments included wound closure rate, histological (collagen density) and stereological examinations, expression of genes involved in repair and angiogenesis (TGF-β and VEGF), inflammatory genes (TNF-α and IL-1β), and wound tissue biomechanical properties. Results: Combined use of dHAM and HBO significantly increased wound closure rate, new epidermis and dermis volume, fibroblast cell and blood vessel density, collagen density, repair and angiogenesis genes, and wound biomechanical properties compared with those in the diabetic group (P<0.05). Also, the expression level of inflammatory genes and neutrophil density significantly decreased in all treatment groups, especially in HBO+dHAM group compared with the diabetic group (P<0.05). Conclusion: dHAM and HBO had a greater effect on the healing process of diabetic wounds when taken together than when each was taken separately.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
To assess the effectiveness of the human amniotic membrane plug for recurrent high myopic macular hole (MH) that already underwent pars plana vitrectomy with internal limiting membrane peeling and ...gas endotamponade.
Sixteen eyes of 16 patients with recurrent high myopic MH were enrolled. A 23-gauge pars plana vitrectomy was performed. Human amniotic membrane plugs were implanted under the neuroretina inside the MH. Twenty percent sulfur hexafluoride or air was used as endotamponades. The patients were instructed to maintain facedown position for 5 days after surgery.
Optical coherence tomography examinations showed that the MHs closed in 15 of the 16 patients (93.75%) 2 weeks after one surgical intervention, and in 100% of patients after second intervention. Mean best-corrected visual acuity improved from 1 logarithm of the minimum angle of resolution (20/200) to 0.67 logarithm of the minimum angle of resolution (20/100) 6 months after surgery. Best-corrected visual acuity remained stable during the 12-month follow-up. One patient had human amniotic membrane plug dislocation after gas absorption that needed a second intervention with new AM plug implantation. No adverse events were reported during the 12-month follow-up.
The first case series of recurrent high myopic MH was reported, assessing the effectiveness of the human amniotic membrane plug to close recurrent MHs in pathologic myopia. All the cases were successful with encouraging best-corrected visual acuity recovery.
Las quemaduras son un problema de interés en salud pública ya que generan un alto índice de morbimortalidad a nivel mundial, las quemaduras térmicas son las más prevalentes y pueden alterar la ...integridad anatómica, funcional y estética de la piel, aspectos fundamentales para la autoestima del paciente y su capacidad para reintegrarse a la sociedad. Al revisar la literatura sobre el tratamiento de estas afecciones encontramos diversos tratamientos, entre ellos el uso de membrana amniótica humana, la cual ha tenido un impacto importante en el manejo de quemaduras al funcionar como andamio biológico con cualidades regenerativas y antiinflamatorias. El presente artículo tiene como objetivo sintetizar la información actual que describe las aplicaciones de membranas amnióticas humanas en quemaduras, realizamos una revisión exploratoria sistemática de la literatura desde 2010 hasta ahora.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•Amniotic membrane (AM) is an excellent natural candidate for wound healing.•Preparation and preservation of AM may negatively affect its biomechanical properties.•Optimization of an effective method ...is critical for a specific application of AM.•The effects of different methods on properties of AM are well discussed.
Human amniotic membrane (AM) has been widely used for tissue engineering and regenerative medicine applications. AM has many favorable characteristics such as high biocompatibility, antibacterial activity, anti-scarring property, immunomodulatory effects, anti-cancer behavior and contains several growth factors that make it an excellent natural candidate for wound healing. To date, various methods have been developed to prepare, preserve, cross-link and sterilize the AM. These methods remarkably affect the morphological, physico-chemical and biological properties of AM. Optimization of an effective and safe method for preparation and preservation of AM for a specific application is critical. In this review, the isolation, different methods of preparation, preservation, cross-linking and sterilization as well as their effects on properties of AM are well discussed. For each section, at least one effective and safe protocol is described in detail.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Extracellular matrix‐based bio‐scaffolds are useful for tissue engineering as they retain the unique structural, mechanical, and physiological microenvironment of the tissue thus facilitating ...cellular attachment and matrix activities. However, considering its potential, a comprehensive understanding of the protein profile remains elusive. Herein, we evaluate the impact of decellularization on the human amniotic membrane (hAM) based on its proteome profile, physicochemical features, as well as the attachment, viability, and proliferation of umbilical cord‐derived mesenchymal stem cells (hUC‐MSC). Proteome profiles of decellularized hAM (D‐hAM) were compared with hAM, and gene ontology (GO) enrichment analysis was performed. Proteomic data revealed that D‐hAM retained a total of 249 proteins, predominantly comprised of extracellular matrix proteins including collagens (collagen I, collagen IV, collagen VI, collagen VII, and collagen XII), proteoglycans (biglycan, decorin, lumican, mimecan, and versican), glycoproteins (dermatopontin, fibrinogen, fibrillin, laminin, and vitronectin), and growth factors including transforming growth factor beta (TGF‐β) and fibroblast growth factor (FGF) while eliminated most of the intracellular proteins. Scanning electron microscopy was used to analyze the epithelial and basal surfaces of D‐hAM. The D‐hAM displayed variability in fibril morphology and porosity as compared with hAM, showing loosely packed collagen fibers and prominent large pore areas on the basal side of D‐hAM. Both sides of D‐hAM supported the growth and proliferation of hUC‐MSC. Comparative investigations, however, demonstrated that the basal side of D‐hAM displayed higher hUC‐MSC proliferation than the epithelial side. These findings highlight the importance of understanding the micro‐environmental differences between the two sides of D‐hAM while optimizing cell‐based therapeutic applications.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background and purpose: One of the most complications of diabetes are chronic skin wounds. Recently Human Amniotic Membrane Scaffold (HAMS) used as a wound dressing. In this study, the impact of HAMS ...on the rate of wound closure and the number of mast cells in the granulation tissue of diabetic rats was evaluated. Materials and methods: 45 diabetic rats were divided into 3 groups: healthy wound, diabetic wound, and diabetic wound transplanted with HAMS. 30 days after diabetes induction via injecting 55mg/kg of Streptozotocin, a circular wound with a diameter of 15mm was created. HAMS was transplanted to the wound and the percentage of wound closure and the density of type 1, 2 and 3 mast cells in the granulation tissue were evaluated on days 7, 14 and 21. Results: HAMS transplantation significantly enhanced the wound closure compared to diabetic group (P<0.05). Comparing to healthy group, the number of all types of mast cells and their total number in diabetic group was significantly decreased on day 7 (P<0.001) and significantly increased on days 14 and 21 (P<0.001). However, these changes modulated in HAMS transplanted group, in which in all cases except for type 3 mast cell on day 7 there were significant differences compared to diabetic group (P<0.01). Moreover, in HAMS transplant group, the number of type 1 and 3 mast cells on day 14 reached the level of healthy group. Conclusion: These results suggested that HAMS improves the diabetic wound healing via modulating inflammatory reactions by affecting the mast cells density in the granulation tissue.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Acute hemorrhage can cause significant morbidity and mortality arising from trauma, bleeding disorders, surgical procedures, or obstetric complications. Surgical hemostasis methods may fail to stop ...acute bleeding due to the complex bleeding dynamics of each bleeding type. Therefore, developing safe and effective topical hemostatic agents remains crucial. The human amniotic membrane (hAM) has established clinical evidence of effectiveness in promoting wound healing and tissue regeneration. Despite its unique biological and immunologic properties and its structural composition of established hemostatic elements, the hemostatic role of hAM has not been yet explored. The present study aimed to investigate this potential role and to describe the development protocol and characterization of hAM-derived topical hemostat.
Surface electron microscope (SEM) imaging and Fourier transform infrared (FTIR) spectroscopy were used for characterization, and mouse models with induced peritoneal and tail wound bleeding were employed to evaluate the hemostatic effectiveness using physiological studies, in comparison to a chitosan-based combat-scale hemostat.
The hAM hemostat showed a distinctive composition by SEM and FTIR. Applying equal masses of the hAM hemostat, the commercial hemostat, or a combination reduced peritoneal wound bleeding time to averages of 108.4, 86.2, and 76.8 s, respectively, compared to the control group (300 s). Tail wound bleeding times were similarly reduced with no significant difference between the hAM and the commercial hemostat (P values = 0.29, 0.34 in peritoneal and tail wounds, respectively). Neither hemostat affected coagulation time.
This study describes a simple cost-effective preparation protocol for a hAM-based hemostatic agent. The long-recognized safety, sustainability, and immunotolerance advantages of hAM can establish superiority over commercial hemostats with reported safety concerns. Robust research validation in larger-scale bleeding models is required for wider applications and severe bleeding types.
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BFBNIB, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Human pluripotent stem cell-derived retinal pigment epithelium (iRPE) is an attractive cell source for disease modeling and cell replacement therapy of retinal disorders with RPE defects. However, ...there are still challenges to develop appropriate culture conditions close to in vivo microenvironment to generate iRPE sheets, which mimic more faithfully the characteristics and functions of the human RPE cells. Here, we developed a simple, novel platform to construct authentic iRPE sheets using human amniotic membrane (hAM) as a natural scaffold. The decellularized hAM (dAM) provided a Bruch's membrane (BM)-like bioscaffold, supported the iRPE growth and enhanced the epithelial features, polarity distribution and functional features of iRPE cells. Importantly, RNA-seq analysis was performed to compare the transcriptomes of iRPE cells cultured on different substrates, which revealed the potential mechanism that dAM supported and promoted iRPE growth was the inhibition of epithelial-mesenchymal transition (EMT). The tissue-engineered iRPE sheets survived and kept monolayer when transplanted into the subretinal space of rabbits. All together, our results indicate that the dAM imitating the natural BM allows for engineering authentic human RPE sheets, which will provide valuable biomaterials for disease modeling, drug screening and cell replacement therapy of retinal degenerative diseases.
Engineered RPE sheets have a great advantage over RPE cell suspension for transplantation as they support RPE growth in an intact monolayer which RPE functions are dependent on. The substrates for RPE culture play a critical role to maintain the physiological functions of the RPE in stem cell therapies for patients with retinal degeneration. In this study, we constructed engineered iRPE sheets on the decellularized human amniotic membrane scaffolds, which contributed to enhancing epithelial features, polarity distribution and functional features of iRPE. dAM exhibited the ability of anti-epithelial mesenchymal transition to support iRPE growth. Furthermore, the results of transplantation in vivo demonstrated the feasibility of iRPE sheets in retina regenerative therapy. Engineering RPE sheets on dAM is a promising strategy to facilitate the development of iRPE replacement therapy and retinal disease modeling.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To determinate the efficacy of the human amniotic membrane plugs with sulfur hexafluoride versus human amniotic membrane plug with air as endotamponade to treat macular holes that failed to close ...after vitrectomy plus internal limiting membrane peeling. Multimodal imaging was focused to evaluate preoperative features and postoperative changes.
Prospective interventional comparative study. Twenty eyes of 20 patients affected with macular hole that failed to close were divided into 2 groups: 10 eyes received an amniotic membrane plug with 20% sulfur hexafluoride tamponade and 10 eyes received an amniotic membrane plug with air tamponade. All eyes were studied using multimodal advanced diagnostic tools, such as spectral-domain optical coherence tomography, optical coherence tomography angiography, microperimetry, and adaptive optics to investigate the postoperative results.
In both groups, all macular holes were found successfully closed after 12 months. Mean preoperative best-corrected visual acuity was 20/400 in the SF6 group and 20/250 in air group. Final mean best-corrected visual acuity was 20/63 in both groups. The superficial capillary plexus, studied using optical coherence tomography angiography, showed a statistically significant difference between the treated and the fellow eyes. Adaptive optics images revealed the presence of a photoreceptor cell mosaic in the area of the amniotic membrane plug.
The human amniotic membrane combined with air endotamponade demonstrated its effectiveness to seal macular holes that failed to close after vitrectomy plus internal limiting membrane peeling. Advanced multimodal diagnostic imaging helped us to better understand the modifications associated with the use of the amniotic membrane in these cases.
