Amniotic Membrane Scaffolds Support Organized Muscle Regeneration in A Murine Volumetric Muscle Defect Model

Current treatment for volumetric muscle loss is limited to muscle transfer or acellular collagen scaffold (ACS) therapies that are associated with donor site morbidity and nonfunctional fibrosis, respectively. The aim of this study is to assess the utility of amniotic membrane scaffold (AMS) for volumetric muscle loss treatment.

Methods

Murine quadriceps defects were created and randomized to three groups (n = 5/group): untreated controls, ACS, and AMS. In vivo muscle regeneration volume was quantified by MRI and microcomputed tomography. Muscle explants were analyzed using standard histology and whole-mount immunofluorescence at 8 weeks.

Results

The cross-sectional muscle regeneration ratio was 0.64 ± 0.3 for AMS, 0.48 ± 0.07 for ACS, and 0.4 0 ± 0.03 for controls as assessed by MRI (P = 0.09) and 0.61 ± 0.28 for AMS, 0.50 ± 0.06 for ACS, and 0.43 ± 0.04 for controls as assessed by microcomputed tomography (P = 0.2). Histologically, AMS demonstrated significantly higher cellular density (900 ± 2 70 nuclei/high powered field) than ACS (210 ± 36) and control (130 ± 4) groups (P = 0.05). Immunofluorescence for laminin (AMS 623 ± 11 versus ACS 339 ± 3 versus control 115 ± 7; P < 0.01) and myosin heavy chain (AMS 509 ± 7 versus ACS 288 ± 5 versus control 84 ± 5; P = 0.03) indicated greater organized muscle fiber formation with AMS.

Conclusion

AMS mediated muscle healing was characterized by increased cellular infiltration and organized muscle formation when compared with controls and ACS.

Efficacy of Dehydrated Human Amnion Chorion Membrane in the Treatment of Diabetic Foot Ulcers: A Review

Studies have been conducted to evaluate the efficacy of dehydrated human amnion chorion membrane (dHACM) in treating recalcitrant diabetic foot ulcers. A literature search was performed to review the data collected from the use of dHACM allografts. Two products were explicitly named in these publications, EpiFix and AmnioBand Membrane. Relevant results included the healing rate, number of wounds healed, and number of grafts used. Data had supported the potential of lowering the overall cost to manage a wound despite a relatively higher cost per dressing. However, discrepancy was observed in the rate of healing between several of the studies. Nonetheless, dHACM had demonstrated improvement in healing of recalcitrant diabetic foot ulcers compared to standard of care alone. These results provide grounds for more inclusive research on dHACM in the future.

Fish skin grafts compared to human amnion/chorion membrane allografts: A double-blind, prospective, randomized clinical trial of acute wound healing

Chronic, nonhealing wounds consume a great deal of healthcare resources and are a major public health problem, associated with high morbidity and significant economic costs. Skin grafts are commonly used to facilitate wound closure. The grafts can come from the patient's own skin (autograft), a human donor (allograft), or from a different species (xenograft). A fish skin xenograft from cold-water fish (Atlantic cod, Gadus morhua) is a relatively recent option that shows promising preclinical and clinical results in wound healing. Chronic wounds vary greatly in etiology and nature, requiring large cohorts for effective comparison between therapeutic alternatives. In this study, we attempted to imitate the status of a freshly debrided chronic wound by creating acute full-thickness wounds, 4 mm in diameter, on healthy volunteers to compare two materials frequently used to treat chronic wounds: fish skin and dHACM. The purpose is to give an indication of the efficacy of the two therapeutic alternatives in the treatment of chronic wounds in a simple, standardized, randomized, controlled, double-blind study. All volunteers were given two identical punch biopsy wounds, one of which was treated with a fish skin graft and the other with dehydrated human amnion/chorion membrane allograft (dHACM). In the study, 170 wounds were treated (85 wounds per group). The primary endpoint was defined as time to heal (full epithelialization) by blinded assessment at days 14, 18, 21, 25, and 28. The superiority hypothesis was that the fish skin grafts would heal the wounds faster than the dHACM. To evaluate the superiority hypothesis, a mixed Cox proportional hazard model was used. Wounds treated with fish skin healed significantly faster (hazard ratio 2.37; 95% confidence interval: (1.75-3.22; p = 0.0014) compared with wounds treated with dHACM. The results show that acute biopsy wounds treated with fish skin grafts heal faster than wounds treated with dHACM.

Comparative efficacy of nine different dressings in healing diabetic foot ulcer: A Bayesian network analysis

BACKGROUND

There is a wide variety of dressings currently available for the treatment of diabetic foot ulcers (DFUs). Because of a lack of evidence from head-to-head randomized controlled trials (RCTs), the relative effects of these dressings in DFU patients remain unclear. This study compared the efficacy of nine dressings in healing DFU.

METHODS

A literature search was performed of the MEDLINE (PubMed), EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) databases. Reports published from 1993 to 2017 focusing on dressings for healing DFU were identified.

RESULTS

Twenty-one RCTs, with a total of 2159 patients, were included in the present study. Bayesian network analysis showed that amniotic membrane dressings were superior to alginate, basic wound contact, foam, honey-impregnated, hydrocolloid, and iodine-impregnated dressings. Hydrogel dressings were better than basic wound contact dressings. Other dressings showed no significant differences. According to the probability of ranking results, amniotic membrane and hydrogel dressings are preferred for healing DFUs.

CONCLUSIONS

The nine dressings evaluated in this study had different advantages in promoting the healing of DFU, but most differences among the dressings were not significant. According to the analysis of rank probability, amniotic membrane and hydrogel dressings are the most advantageous in terms of promoting DFU healing. It is recommended that the most suitable dressing should be selected taking into consideration exudate control, comfort, and cost.

The Role of Biological Skin Substitutes in Stevens-Johnson Syndrome: Systematic Review

Stevens-Johnson syndrome (SJS) is a disease that causes skin exfoliative lesions, characterized by fever, necrosis, and epidermal detachment. Biological skin substitutes may be considered interesting options for the treatment of this disease. This study aims at identifying in the literature the evidence on the current role of these biomaterials in the treatment of SJS and its related diseases. A systematic review with a search period between 2003 and 2017 was carried out, consulting the Lilacs, BVS, and PubMed databases. The quality of the included studies was evaluated by the Oxford Center for Evidence-Based Medicine Classification, for evaluating levels of evidence from the scientific publications. Ninety-five publications were found, and after applying inclusion and exclusion criteria, they resulted in 9 articles. In total, 20 patients with 73.87% average of body surface affected received SJS skin treatment with some biological substitutes, among them are cutaneous allograft, amnion, and xenograft. Mortality rate was 10%, and in these situations, literature indicates mortality rates ranging from 25% to 70%. Effectiveness of the use of biological dressings may be a possible explanation for this finding. Findings indicate the use of these biomaterials may favor reepithelialization, reduce water loss, decrease the chance of infection, and, consequently, improve the survival of patients with SJS and toxic epidermal necrolysis. Biological skin substitutes have characteristics that make them very promising in the topical treatment of these wounds, but their use remains very restricted in the treatment of SJS.

Human acellular amniotic membrane implantation for lower third nasal reconstruction: a promising therapy to promote wound healing

Background

The lower third of the nose is one of the most important cosmetic units of the face, and its reconstructive techniques remain a big challenge. As an alternative approach to repair or regenerate the nasal tissue, the biomaterial-based strategy has been extensively investigated. The aim of this study is to determine the safety and efficacy of human acellular amniotic membrane (HAAM) to repair the full-thickness defects in the lower third of the nose in humans.

Methods

In this study, 180 patients who underwent excision of skin lesions of the lower third of the nose from 2012 to 2016 were included; of the patients, 92 received HAAM and Vaseline gauze treatments, and the other 88 patients received Vaseline gauze treatment only. The haemostasis time and the duration of operation were recorded during surgery; after surgery, the time to pain disappearance, scab formation and wound healing, and the wound healing rate were measured.

Results

Immediately after the HAAM implantation, a reduction of the haemostasis time and an accelerated disappearance of pain were observed. Compared with the control group, the formation and detachment of scab in patients who received the HAAM implantation were notably accelerated, postoperatively. When the diameter of the lesion exceeded 5 mm, the HAAM implantation was found to enhance the wound healing, although this enhancement was not seen when the diameter was less than 5 mm. Additionally, the HAAM implantation significantly reduced bleeding, wound infection and scar formation, postoperatively.

Conclusions

HAAM-assisted healing is a promising therapy for lower third nasal reconstruction leading to rapid wound healing and fewer complications and thus has considerable potential for extensive clinical application in repairing skin wounds.

Trial registration

ChiCTR1800017618, retrospectively registered on July 08, 2018.

Biological effects of amniotic membrane on diabetic foot wounds: a systematic review

Objective:

The amniotic membrane has biological properties that are beneficial to the wound healing process of diabetic foot ulcers (DFU). Our aim is to analyse the scientific evidence found in literature on the use of the amniotic membrane to stimulate DFU healing.

Method:

A systematic review of amniotic membrane's influence was undertaken, using the search terms ‘placenta’ ‘diabetic foot’ ‘amnion’ and biological dressing’, assessing the outcomes ‘wound healing’ and ‘wound healing time’, in DFU. Following the inclusion and exclusion criteria, randomised controlled trials (RCT) were identified, and the risk of bias was analysed according to the Cochrane risk of bias tool. We conducted a meta-analysis of the two outcomes to evaluate the level of evidence.

Results:

We identified six clinical trials, with a total of 331 patients. The most common risks of bias in the studies were selection, attrition, and detection biases. From the meta-analysis, the difference of the intervention group (amnion) in relation to the control group was statistically significant. We found that wound healing in the group treated with amniotic membrane occurs 2.32 times more often and is 32 days faster in comparison with the group that used conventional dressings.

Conclusion:

There is statistical evidence to support the effectiveness of amniotic membrane in comparison with other conventional dressings. In addition, there is a clear tendency for the use of amniotic membrane treatment to result in a larger number of DFUs healing at a quicker rate.

Biological effects of amniotic membrane on diabetic foot wounds: a systematic review

OBJECTIVE

The amniotic membrane has biological properties that are beneficial to the wound healing process of diabetic foot ulcers (DFU). Our aim is to analyse the scientific evidence found in literature on the use of the amniotic membrane to stimulate DFU healing.

METHOD

A systematic review of amniotic membrane's influence was undertaken, using the search terms 'placenta' 'diabetic foot' 'amnion' and biological dressing', assessing the outcomes 'wound healing' and 'wound healing time', in DFU. Following the inclusion and exclusion criteria, randomised controlled trials (RCT) were identified, and the risk of bias was analysed according to the Cochrane risk of bias tool. We conducted a meta-analysis of the two outcomes to evaluate the level of evidence.

RESULTS

We identified six clinical trials, with a total of 331 patients. The most common risks of bias in the studies were selection, attrition, and detection biases. From the meta-analysis, the difference of the intervention group (amnion) in relation to the control group was statistically significant. We found that wound healing in the group treated with amniotic membrane occurs 2.32 times more often and is 32 days faster in comparison with the group that used conventional dressings.

CONCLUSION

There is no statistical evidence to support the effectiveness of amniotic membrane in comparison with other conventional dressings. However, there is a clear tendency for the use of amniotic membrane treatment to result in a larger number of DFUs healing at a quicker rate.

Amnion Membrane in Diabetic Foot Wounds: A Meta-analysis

Background:

Amniotic membrane is tissue obtained from human placenta rich in cytokines, growth factors, and stem cells that possess the ability to inhibit infection, improve healing, and stimulate regeneration.

Methods:

A meta-analysis was performed examining randomized controlled trials comparing amniotic tissue products with standard of care in nonhealing diabetic foot ulcers including PubMed, Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews.

Results:

A search of 3 databases identified 596 potentially relevant articles. Application of selection criteria led to the selection of 5 randomized controlled trials. The 5 selected randomized controlled trials represented a total of 311 patients. The pooled relative risk of healing with amniotic products compared with control was 2.7496 (2.05725–3.66524, P < 0.001).

Conclusions:

The current meta-analysis indicates that the treatment of diabetic foot ulcers with amniotic membrane improves healing rates in diabetic foot ulcers. Further studies are needed to determine whether these products also decrease the incidence of subsequent complications, such as amputation or death, in diabetic patients.

Robotic repair of a vesicovaginal fistula in an irradiated field using a dehydrated amniotic allograft as an interposition patch

We report the case of a 66 year old female with a supratrigonal vesicovaginal fistula (VVF) that developed after undergoing radical hysterectomy, chemotherapy and pelvic radiation therapy for advanced cervical cancer. VVF repairs in an irradiated field are known to be complicated procedures with significant morbidity and a high rate of failure due to the effect of radiation. Amniotic membranes have been demonstrated to improve healing rates in difficult to heal wounds. To decrease morbidity a minimally invasive robotic procedure was performed and a dehydrated amniotic allograft patch was used to augment tissue healing. The VVF was repaired using the da Vinci Surgical System and the amniotic membrane was used as an interposition patch over the repair. There were no operative or postoperative complications and the patient was discharged home on postoperative day one. A cystogram performed 3 weeks postoperatively demonstrated a healed fistula. Follow-up at 5 months revealed no incontinence. This is the first reported case of a robotic VVF repair performed in an irradiated pelvis and the first use of an amniotic membrane allograft in the repair a VVF.