The use of autologous PRP gel as an aid in the management of acute trauma wounds

Efficacy and Safety of Platelet-Rich Plasma on Bronchopleural Fistula: A Pilot Prospective Cohort Study

INTRODUCTION

Bronchopleural fistula (BPF) is associated with high morbidity and mortality rates in patients undergoing pulmonary resections. Surgery, bronchoscopy, and conservative management have their limitations for small fistulas. Platelet-rich plasma (PRP) has regenerative properties, which might be efficient in enhancing tissue recovery and repairing small BPF. This study aimed to investigate efficacy and safety of PRP on BPF.

METHODS

This is a pilot prospective cohort study. Patients whose fistulas smaller than 4mm were enrolled in this study, treated with PRP under bronchoscopy and followed up at 2 weeks and 4-6 weeks after the last PRP treatment. The cure rate, improvement rate and ineffectiveness rate were investigated. The severity of respiratory symptoms was evaluated by modified Medical Research Council dyspnea scale (mMRC) and COPD Assessment Test (CAT). The recurrence of fistula, new infection and mortality rate were examined. Adverse events were documented to explore the safety profile of PRP therapy.

RESULTS

A total of 16 patients (mean age, 50.1 years) met the eligibility criteria. The median time from the first PRP treatment to the closure of the fistula was 12.0 (IQR 6.0, 21.5) days. Our findings indicate an effectiveness rate of 87.6%, with 68.8% of cure and 18.8% of improvement, along with significant improvement of respiratory symptoms evaluated by mMRC (P<0.001) and CAT (P<0.001). No recurrent of fistulas, newly developed infection, or death was observed. Adverse events of the procedure were most mild (82.6%) and temporary.

CONCLUSIONS

PRP is a potential treatment for small BPF and is well tolerated.

Platelet-rich plasma and plasma rich in growth factors in extra-oral wound care

This narrative review evaluates the existing literature on the clinical efficacy and safety of platelet-rich plasma (PRP) and plasma rich in growth factors (PRGFs) in extra-oral wound care, considering their potential benefits and drawbacks. The review specifically focuses on the impact of these treatments on patients' quality of life, pain management, treatment costs, recurrence rates, and potential complications. Given the extensive literature and diverse range of extra-oral wound types in which these autologous platelet concentrates have been applied, this narrative review focuses on the most frequently described wound types, including diabetic foot ulcers, venous leg ulcers, pressure ulcers, surgical wounds, and burns. The use of PRP has been reported in various medical specialties, with a low risk of adverse events. While there is a growing interest in the use of PRGF with promising results, the available literature on this topic is still limited. Only a few studies evaluated patients' perception of the treatment and the relationship between treatment costs and clinical outcomes. Data on recurrence rates and complications also vary across studies. In conclusion, PRP and PRGF show promise as alternatives or as adjunctive therapies to conventional treatments for various extra-oral wounds and ulcers, leading to reduced wound size and accelerated healing time but should be considered on a case-by-case basis, taking into account the type and severity of the wound.

Evaluation of the Efficacy of Platelet-Rich Plasma Injections With and Without Microneedling for Managing Atrophic Facial Acne Scars: A Prospective Comparative Study

Background and aim The majority of acne has the potential to transform into facial scars, which have a physical and psychological effect on the individual. There are plenty of treatment options to manage such scars. The aim of this study is to assess the comparative effect of the injection of platelet-rich plasma (PRP) alone, with that of the injection of PRP with microneedling, in the reduction of atrophic facial acne scars.  Methods A total of 30 participants were included in this study, divided into two groups (n = 15). Patients in Group I received intradermal injection of PRP only, and Group II included patients receiving intradermal injection of PRP with microneedling. The scar appearance was evaluated at baseline, after one, two, and three months using Goodman Baron's scar scale. The statistics were analysed using the Chi-square and Student's t-tests.  Results Patients in the PRP with microneedling group had lower acne scar scores on the Goodman Baron scale compared to those who received only PRP. The acne scores were statistically significant (p-value < 0.05) in the second and third months of treatment in Group II.  Conclusion The addition of microneedling to PRP has proven to be effective in the reduction of facial acne scars. However, different types of scars require different modalities of treatment, and the final decision lies in the hands of the operator and the requirements of the patients.

Efficacy of platelet-rich plasma in alleviating split skin graft morbidities

Introduction

Skin grafting is a routinely employed technique to cover the skin defect. Though the skin grafts are technically effortless, they are tiresome because of the prolonged duration of hospital stay, labor-intensive, demanding repeated dressings, and also create a second wound. Platelet-rich plasma (PRP) is one that has a higher concentration of platelets than the blood. Alpha granules of the platelets are rich in growth factors.

Aims and Objectives

To assess the effect of PRP on split-thickness skin graft uptake and donor site healing.

Materials and Methods

In a single-center-based prospective study done from August 2018 to June 2020, 60 patients with acute and chronic wounds were divided into two equal groups. Autologous PRP was applied on the recipient wound bed and donor site in PRP group, and conventional methods like staples/sutures were used to anchor the skin grafts and standard of care of the donor site in a control group.

Results

Instantaneous graft adhesion was observed in all patients of PRP group. The first graft inspection was delayed. Seroma, hematoma, total number of dressings, and duration of stay in hospital were significantly reduced in the PRP group. Donor site pain in the postoperative period was notably reduced in PRP group. PRP also remarkably hastened the donor site healing.

Conclusion

The application of PRP promotes graft take, minimizes complications, enhances donor site wound healing, mitigates donor site pain, and has immense economic benefits due to the reduced number of dressing changes and shorter hospital stay.

The use of platelet-rich plasma in wound healing and vitiligo: A systematic review and meta-analysis

OBJECTIVE

To critically assess the effect and safety of platelet-rich plasma (PRP) in chronic wounds and vitiligo.

METHODS

A systematic literature searching was performed. Results were expressed as weight mean difference (WMD) or risk ratio (RR) with 95% confidence intervals (CIs). Pooled estimates were performed using a fixed-effects model or random-effects model, depending on the heterogeneity among studies.

RESULTS

A total of 27 studies were included in this meta-analysis. In patients with chronic diabetic ulcers, PRP significantly increased proportion of complete wound healing, percentage of wound area healed, and shortened the complete wound healing. In venous ulcers, PRP improved the epithelialized area and percentage of wound area healed. In vitiligo, PRP had better results in degree of improvement and mean repigmentation than controls. Regarding the safety profile, PRP did not increase the risk of infection in patients with chronic diabetic ulcers. Meta-regression revealed that source of PRP and preparation method of PRP significantly affected the proportion of complete wound healing, whereas age, gender, country, duration of wound, and wound size had no impact on this outcome.

CONCLUSION

PRP is effective and safe, and can be used as a potential therapeutic adjunct or alternative treatment in chronic wounds of multiple etiologies and vitiligo.

Platelet-Rich Plasma and Acellular Dermal Matrix in the Surgical Treatment of Hidradenitis Suppurativa: A Comparative Retrospective Study

(1) Introduction: Hidradenitis suppurativa (HS) is an inflammatory skin disease with recurrent, chronic, painful, and purulent skin lesions. Topical or systemic antibiotics are the most widely used treatments for the management of mild stages of the disease. In chronic cases (Hurley II/III), wide excision of lesions should be considered. During reconstructive surgery, the most problematic aspect is wound closure. Very large excisional wounds require reconstructive techniques such as skin flaps, skin grafts, or both. Surgical methods have their limitations, so reconstructive methods in HS surgery need to be continuously improved through the use of, for example, platelet-rich plasma and acellular dermal matrix; (2) Methods: The aim of this study was to evaluate the clinical outcomes and efficacy of surgical treatment of patients with HS using local skin flaps injected with PRP compared to a group of local skin flaps without platelet-rich plasma injection, an acellular dermal matrix, and split-thickness skin graft co-grafts. Sixty-one patients (29 males and 32 females) were included in the study. Most patients were characterized by Hurley grade III HS; (3) Results: The use of PRP injection in reconstructions (skin flaps) improved healing and reduced the number of complications, a notable trend in this study. A co-graft of acellular dermal matrix and split-thickness skin graft gave better therapeutic results than split-thickness skin graft alone (fewer days in hospital, fewer postoperative complications); (4) Conclusions: PRP injected into skin flaps, co-grafted acellular dermal matrix, and split-thickness skin grafts are good options for the surgical treatment of hidradenitis suppurativa.

Autologous Platelet and Extracellular Vesicle-Rich Plasma as Therapeutic Fluid: A Review

The preparation of autologous platelet and extracellular vesicle-rich plasma (PVRP) has been explored in many medical fields with the aim to benefit from its healing potential. In parallel, efforts are being invested to understand the function and dynamics of PVRP that is complex in its composition and interactions. Some clinical evidence reveals beneficial effects of PVRP, while some report that there were no effects. To optimize the preparation methods, functions and mechanisms of PVRP, its constituents should be better understood. With the intention to promote further studies of autologous therapeutic PVRP, we performed a review on some topics regarding PVRP composition, harvesting, assessment and preservation, and also on clinical experience following PVRP application in humans and animals. Besides the acknowledged actions of platelets, leukocytes and different molecules, we focus on extracellular vesicles that were found abundant in PVRP.

The Role of Platelet-Rich Plasma in Reducing Pain, Pruritis, and Improving Wound Healing of Skin Graft Donor Site

Background  Wound healing is a dynamic and complex process. Therefore, no single agent can efficiently mediate all aspects of the wound healing process. Split-thickness graft has become a workhorse of plastic surgery for wound or raw area cover. In this study, we evaluate the effectiveness of autologous platelet-rich plasma (PRP) on the donor site and its effect in pain, purities, and epithelization. Materials and Methods  This is a prospective study. A total of 15 patients were included who underwent split skin grafting for burns, trauma, or post-tumor excision raw area. PRP was prepared using standard described procedure. The donor site raw area after harvesting split-thickness graft was measured and the surface area was divided into two equal halves. One half was dressed using PRP and the other half was dressed using paraffin gauze piece only. The dressings were changed weekly for 3 weeks. Observation  We found significant reduction in severity of pain and pruritis in the PRP group as compared with control group. Epithelization was faster in the PRP group on day 7 and 14, but the overall healing time was nearly the same by day 21. The side-by-side dressing thus show a definite improvement in the post-split-thickness skin graft wound care and PRP as a good dressing alternative. Conclusion  Autologous PRP is very effective adjuvant in management of skin graft donor site. Its role in relieving pain and pruritis over donor site significantly improves patient's discomfort postoperatively. It helps in early and painless wound healing. However, we recommend for larger clinical study for better understanding of the efficacy of this blood product.

Characterization of a Human Platelet Lysate-Loaded Keratin Hydrogel for Wound Healing Applications In Vitro

One of the promising approaches to facilitate healing and regenerative capacity includes the application of growth-factor-loaded biomaterials. Human platelet lysate (hPL) derived from platelet-rich plasma through a freeze-thaw process has been used as a growth factor rich therapeutic in many regenerative applications. To provide sustained local delivery of the hPL-derived growth factors such as epidermal growth factor (EGF), the hPL can be loaded into biomaterials that do not degrade rapidly in vivo. Keratin (KSO), a strong filamentous protein found in human hair, when formulated as a hydrogel, is shown to sustain the release of drugs and promote wound healing. In the current study, we created a KSO biomaterial that spontaneously forms a hydrogel when rehydrated with hPL that is capable of controlled and sustained release of pro-regenerative molecules. Our study demonstrates that the release of hPL is controlled by changing the KSO hydrogel and hPL-loading concentrations, with hPL loading concentrations having a greater effect in changing release profiles. In addition, the 15% KSO concentration proved to form a stable hydrogel, and supported cell proliferation over 3 days without cytotoxic effects in vitro. The hPL-loaded keratin hydrogels show promise in potential applications for wound healing with the sustained release of pro-regenerative growth factors with easy tailoring of hydrogel properties.

Clinical Effect of Bushen Huoxue Method Combined with Platelet-Rich Plasma in the Treatment of Knee Osteoarthritis and Its Effect on IL-1, IL-6, VEGF, and PGE-2

Objective

To observe the clinical efficacy of the Bushen Huoxue method combined with platelet-rich plasma (PRP) in the treatment of knee osteoarthritis (KOA) and its effect on serum and joint fluid interleukin-1 (IL-1), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and prostaglandin E2 (PGE-2).

Methods

A total of 64 cases of KOA diagnosed and treated from January 2020 to January 2021 were randomly divided into research group and control group, with 32 cases in each group. The control group was treated with PRP, and the research group took the prescription of the Bushen Huoxue method on the basis of the control group. The clinical efficacy was assessed according to the criteria in "the diagnosis and Treatment of osteoarthritis," osteoarthritis index score and pain visual analogue score (VAS). Serum and articular fluid VAS, IL-1, IL-6, VEGF, and PGE-2 levels were detected by the enzyme-linked immunosorbent assay (ELISA).

Results

The clinical effective rate of the research group was 93.8%, which was significantly higher than that of the control group (90.6%). There was no significant difference in the scores of osteoarthritis index between the two groups before treatment, but the scores of both groups decreased after treatment and was lower in the research group than those in the control group. VAS was significantly decreased in two groups after treatment and it was lower in the research group than that in the control group. After treatment, the levels of IL-1, IL-6, and PGE-2 in serum and articular fluid all indexes were decreased, and the levels in the research group were lower than those in the control group.

Conclusions

PRP joint cavity injection combined with oral administration of Bushen Huoxue prescription, and PRP joint cavity injection alone can improve the efficacy of KOA, relieve knee pain, and promote the recovery of knee function. The mechanism may be related to the reduction of IL-1, IL-6, VEGF levels, and PGE-2 levels in the serum and joint fluid. However, the efficacy of combination therapy was superior to PRP alone.

Reducing split-thickness skin grafting donor site agony; faster healing and decreased pain-role of platelet-rich plasma

INTRODUCTION

The split-thickness skin graft harvested donor site is associated with prolonged healing, discomfort, and pain. Platelet-rich plasma (PRP) contains platelet-derived growth factors and has been widely used in chronic wounds and skin graft donor sites. PRP application is known to accelerate wound epithelialization rates, and also reduce postoperative wound site pain.

MATERIALS AND METHODS

We assessed 20 patients admitted to our hospital service who underwent split-thickness skin grafting (STSGs) with proximal half of the donor site treated with PRP. The dressing was conducted on postoperative day 7, 14, and 21. The donor site healing was assessed with serial photographs and donor site pain measured by numerical rating scale.

RESULTS

Complete healing of wounds (epithelialization) was present in 12 (60%) patients dressed with PRP. Pain on opening dressing was an average of 3.5 in PRP dressed wounds and 6.35 in control wounds. Patients dressed without PRP, none of them had complete epithelialization. All patients had partial healing and were less than the donor site dressed with PRP. Based on these results, skin graft donor site with PRP showed accelerated healing and reduced pain and discomfort compared to control without PRP.

CONCLUSION

PRP is a beneficial adjunct for reducing donor site pain and increased healing of donor site following STSG harvest.

Effect of Cryo-Processing on Platelet-Rich Autoplasma Preparations

Platelet-derived growth factor (PDGF) plays an important role in angiogenesis, affects activation of migration and proliferation of mesenchymal stem cells, fibroblasts, smooth muscle cells, osteoblasts; activation of migration of monocytes, macrophages, and neutrophils.

The aim of the investigation was to study the effect of cryo-processing on the qualitative properties of platelet-rich autoplasma (PRP) at different time intervals.

Autologous Platelet-Rich Plasma Efficacy in the Field of Regenerative Medicine: Product and Quality Control

Platelet-rich plasma (PRP) has emerged as a significant regenerative therapy used alone or combined mainly with stem cells, autologous fat grafts, hyaluronic acid, and biomaterials in a variety of medical fields, especially in hair regrowth, wound healing, and sports and rehabilitation medicine. However, the results obtained with this biologic therapy are heterogeneous and conflicting. The observed disparities in the effectiveness of PRP therapies may be due to a lack of standardization in blood processing and preparation. This article is aimed at reviewing the main biological parameters that need to be documented for a thorough reporting of quantitative and qualitative characteristics of the PRP injected, to allow a comparison between the quality of samples and the clinically obtained results and advance the efforts towards treatment standardization.

Effects of Xenogen Mesenchymal Stem Cells and Cryo-Platelet Gel on Intractable Wound Healing in Animal

BACKGROUND

Today, the effects of growth factors and mesenchymal stem cells (MSCs) in promoting wound healing have been confirmed.

OBJECTIVE

This study aimed to investigate the effect of MSCs and platelet cryogel on wound healing.

METHODS

40 male Wistar rats were randomly divided into five groups (n=8). The control group just dressed, the second group received platelet cryogel, the third group received platelet cryogel containing MSCs, the fourth group received plasma, and the fifth group received plasma plus MSCs. The biopsy was obtained from the wounds in 2, 4, 6, and 8 days of the treatment. Then pathological evaluation was conducted. Finally, qRT-PCR was performed to determine angiogenesis.

RESULTS

The intervention groups had faster wound healing and lower wound area than the control group (p<0.05). The highest wound healing rate and the smallest wound area were observed in the group after receiving platelet cryogel plus MSCs. Angiogenesis, fibrosis, myoepithelial and epithelialization in the pathologic examination using H & E staining were not significantly different between the groups. The expression of Ang-1 in the intervention groups was higher than the control group and the highest expression was observed in the platelet cryogel plus MSCs, followed by the platelet cryogel group. The expression of VEGF in the plasma plus MSCs was higher than in the other groups.

CONCLUSION

Further studies require to determine the effects of combined use of platelet cryogel plus MSCs on other types of wounds and evaluate mechanisms involved in wound healing like collagenases and inflammatory factors.

Level of Evidence on Platelet-rich Plasma in Plastic Surgery

BACKGROUND

Despite the increased popularity of platelet-rich plasma (PRP) in plastic surgery, there is no detailed analysis on the level of evidence on PRP use in plastic surgery. As the number of applications of PRP in plastic surgery increases, it is important for plastic surgeons to understand the scientific and validated evidence behind its use. Therefore, we performed a literature review to identify current level of evidence on platelet-rich plasma in plastic surgery.

METHODS

We performed a computerized search of platelet-rich plasma in plastic surgery using the MEDLINE, Cochran Library, and EMBASE databases. Data regarding the type of study, PRP application, and outcomes were collected. Then, the level of evidence was assigned using the American Society of Plastic Surgeons Level of Evidence Rating.

RESULTS

Our search identified 105 articles, and about 78.1% of studies were lower-quality studies: 37 level-III articles (35.2%), 32 level-IV articles (30.5%), and 13 level-V articles (12.4%). There were only 6 level-I articles and 17 level-II studies. Level-I studies were on facial rejuvenation using a laser, carpal tunnel release, cleft lip repair, trauma wounds, breast reconstruction using latissimus dorsi, and hair regrowth.

CONCLUSIONS

Our review of the literature shows that the level of evidence on PRP use in plastic surgery is low (21.9%). Nevertheless, we believe level-III to level-V studies are still valuable, as performing high-level quality studies in plastic surgery is difficult due to variability in surgical techniques, experiences, and materials.

Combination of platelet rich plasma and stromal vascular fraction on the level of vascular endothelial growth factor in rat subjects experiencing deep dermal burn injury

Background

The healing process of burns includes coagulation, inflammation, and remodeling. Vascular endothelial growth factor (VEGF) is involved throughout this healing process. Stem cells from the platelet-rich plasma (PRP) with stromal vascular fraction (SVF) can increase concentrations of growth factors, including VEGF. This is expected to accelerate burn healing. The aim of this study was to determine the effect of a combination of PRP and SVF on VEGF levels in a rats model of deep dermal burn wound healing.

Materials and methods

This is an experimental research study in rats using a post-test control group design with 4 groups: A) control, B) Vaseline, C) topical PRP and SVF, and D) PRP and SVF injection. Burn wounds were induced according to the modified Guo method.

Results

In a rats model of deep dermal wound healing, topical Vaseline significantly increased serum VEGF compared to control. Topical application and injection of stem cells also significantly increased serum VEGF compared to control and Vaseline. The VEGF concentration was significantly higher following injection of PRP and SVF, suggesting that the injection route is more effective at increasing VEGF levels compared to the topical application of stem cells.

Conclusion

The combination of PRP and SVF, either by injection or topical application, can increase VEGF levels during the healing process from deep dermal burns.

•

Stem cells can increase concentrations of growth factors.

•

Topical application and injection of stem cells significantly increased serum VEGF compared to control.

•

The VEGF concentration was significantly higher following injection of PRP and SVFs.

•

The injection route of stem cells is more effective at increasing VEGF levels compared to the topical application.

Current applications of platelet gels in wound healing-A review

Human platelets play important roles in several physiologic and pathologic processes. Platelet concentrates are activated with thrombin or calcium, resulting in a viscous coagulum (platelet gel [PG]), composed of 95% platelets at least. PG is increasingly used for the treatment of a variety of soft and hard tissue defects, most notably in the management of chronic non-healing wounds. During wound healing, platelets not only play a critical role in primary hemostasis and thrombosis, but also release growth factors and cytokines to promote tissue regeneration, enhance collagen synthesis, and trigger an immune response. This review addresses a variety of aspects relevant to the functions of well-known platelet growth factors, animal and clinical studies of PG in the last decade, and different sources of platelets for PG. PG is used for non-healing chronic wounds, such as oral ulcerations related to epidermolysis bullosa and chronic graft-versus-host disease, for those, the traditional treatment effect is poor. PG maybe provide a new therapeutic direction for these diseases. Nevertheless, some uncertainty is present, the number of clinical studies is not enough. Hence, randomized controlled trials are still required to study the potential of the use of PG in the near future.

Injectable gelatin microspheres loaded with platelet rich plasma improve wound healing by regulating early inflammation

We investigated the potential of gelatin microspheres (GMs) loaded with platelet-rich plasma (PRP) to enhance their wound healing effect. Platelets from the PRP were immobilized onto GMs to form biomimetic bioreactor GM+PRP. The therapeutic effect of this agent was further investigated in vivo on a wound-healing model in rats. Wounds were locally injected with phosphate buffered saline (PBS), GM, PRP, and GM+PRP. Wound healing rate, vessel density, and inflammation level were measured histologically, by RT-PCR, and by Western blotting at days 3, 7, 14, and 21. Platelets on GM caused a continuous high release in both interleukin-10 and metalloproteinase-3 compared with PRP alone. Both GM+PRP and PRP successfully accelerated the wound healing process, while GM alone did not improve the wound healing process compared with the untreated control. Wounds treated with GM+PRP resulted in shorter healing period and improved dermal structure. GM+PRP improved angiogenesis in the wound by increasing expression of angiogenic factors. GM+PRP prolonged and enhanced the cytokine release profile compared with PRP. By promoting the inflammatory and angiogenic responses, GM+PRP has the potential to improve wound healing. Our findings demonstrate that GMs are an injectable carrier that enhanced the therapeutic effects of PRP.

Platelet-rich plasma and/or sildenafil topical applications accelerate and better repair wound healing in rats through regulation of proinflammatory cytokines and collagen/TGF-β1 pathway

Platelet-rich plasma (PRP) composites of various cytokines and growth factors which have the potential to activate and speed the process of wound repair. Sildenafil also is a potent stimulator of angiogenesis which favors its potential effects on wound healing in several models. Existing work planned to examine the effectiveness of topical application of PRP and/or sildenafil citrate hydrogel (SCH) in a non-splinted excision skin wound model. Adult male rats were allocated into control, PRP, SCH, and PRP/SCH groups. On the 7th and 14th days, blood and tissue samples were collected for hematobiochemical, histopathological, and immunohistochemistry analyses. PRP and/or SCH topical treatments caused an enhancement of wound healing parameters, including a rapid switch from inflammatory phase to connective tissue stage evident by less systemic hematological changes and decreased values of proinflammatory cytokines (IL-6, TNF-α, and IL-1β) and C-reactive protein (CRP) on the 7th or 14th days post-wounding. Also, tissue hydroxyproline, collagen, nitrite, and total protein contents were higher in therapeutically handled wounded rats. Histologically, PRP- and/or SCH-treated wounded rats exhibited less necrosis, inflammation, and fibrin with a higher level of granulation tissue formation on the 7th day post-wounding and abundant collagen remodeling, epithelization, and vascularization on the 14th day relative to control. Interestingly, combined PRP and SCH treatment was more efficient in wound healing scoring with less inflammation, more collagen remodeling, and more epithelization. Our findings confirm the effectiveness of PRP and/or SCH as a topical wound healing treatment, with better skin wound healing with their combination.

Comparison of Platelet-Rich Plasma-Impregnated Suture Material with Low and High Platelet Concentration to Improve Colonic Anastomotic Wound Healing in Rats

Objective

This study was designed to investigate the impact of using suture material impregnated with platelet-rich plasma (PRP) in different platelet concentrations on colonic anastomotic wound healing in rats.

Methods

A total of 24 Sprague Dawley female rats were separated into 3 groups (n = 8 for each) including the control group (CON; standard vicryl suture repair), the low platelet concentrate PRP group (L-PRP; suture material impregnated with PRP containing average 2.7-fold (range, 2.0 to 3.1) higher amount of platelets vs. control), and the high platelet concentrate PRP group (H-PRP; suture material impregnated with PRP containing average 5.1-fold (range, 4.8 to 5.4) higher amount of platelets vs. control). Rats were sacrificed on the postoperative 7^th day for analysis of colonic anastomosis region including macroscopic observation, measurement of anastomotic bursting pressure (ABP), and the hydroxyproline levels and histopathological findings in colon tissue samples.

Results

Total injury scores were significantly lower in the L-PRP and H-PRP groups than those in the control group (median (range) 13.00 (7.00) and 11.50 (6.00) vs. 15.50 (4.00), p < 0.05 and p < 0.01, respectively). ABP values (180.00 (49.00) vs. 124.00 (62.00) and 121.00 (57.00) mmHg, p < 0.001 for each) and tissue hydroxyproline levels (0.56 (0.37) vs. 0.25 (0.17) and 0.39 (0.10) μg/mg tissue, p < 0.001 and p < 0.05, respectively) were significantly higher in the L-PRP group as compared with those in the control and H-PRP groups.

Conclusion

In conclusion, our findings revealed PRP application to colonic anastomosis sutures to promote the anastomotic healing process. The platelet concentration of PRP seems to have a significant impact on the outcome with superior efficacy of L-PRP over H-PRP in terms of bursting pressures and collagen concentration at the anastomotic site.

Alleviation of synovitis caused by joint instability with application of platelet-rich plasma

INTRODUCTION

Synovitis is an early set and persistent change during the progression of osteoarthritis, which causes symptoms such as pain and swelling of the joints. Platelet-rich plasma (PRP) can release quantities of growth factors and cytokines, and is proved effected in promoting restoration of multiple soft tissues.

MATERIALS AND METHODS

In this study, twenty rabbits were used to establish animal model of synovitis, with the method of severing the anterior and posterior cruciate ligaments and removing the medial meniscus. Then the rabbits were evenly divided into the PRP group and the control group, and each group received injections of PRP and saline respectively once a week for 3 weeks consecutively, with the first injection administered 3 weeks postoperatively.

RESULTS

The platelet count, the concentrations of growth factors in PRP and whole blood were investigated, and the IL-1β concentration in the joint fluid was detected via ELISA. The synovium as well as the adjacent articular cartilage were collected for histological assessment. The platelet concentration in PRP is 6.8 fold of that in the whole blood. The IL-1β level in the PRP group was lower than that in the control group 2 and 3 weeks after the administration of PRP. Histological investigation showed that the inflammatory reaction of the synovium and impact on the cartilage was much abated in the PRP group.

CONCLUSIONS

PRP can effectively alleviate the synovitis caused by osteoarthritis following loss of joint stability. Given the autologous origin, its low cost and low risk features of PRP, it's a promising choice for OA patients to control the symptoms caused by synovitis.

The effect of magnetic field therapy and electric stimulation on experimental burn healing

Objectives

: In this study, we aimed to compare morphological and histological differences between magnetic field and electric stimulation therapies in an experimental burn injury model in rats.

Materials and methods

Between February 2011 and July 2011, a total of 21 Sprague-Dawley female rats were used in this study. Second-degree burns were induced on the back areas of the rats. All rats were equally divided into three groups including seven in each: the first burn group was treated with antibacterial pomade (Group 1, control group); the second group was treated with both antibacterial pomade and pulsed electromagnetic field therapy (Group 2); and the third group was treated with antibacterial pomade and electric stimulation for 14 days (Group 3).

Results

Earlier re-epithelialization, wound area contraction, reduction of edema, and hyperaemia were observed on gross examination in the pulsed electromagnetic fields and electric stimulation therapy groups compared to the control group. Neovascularization, collagen density, granulation tissue formation, cell proliferation, and inflammatory cell response of the pulsed electromagnetic fields and electric stimulation group increased, compared to the control group, in the histopathological evaluation (p<0.05).

Conclusion

Our study results showed the positive healing effects of electric stimulation and pulsed electromagnetic fields on burn injury. Pulsed electromagnetic fields therapy produced more positive signs of healing than the electric stimulation group.

Evaluation of PSP technique including dot peeling, subcision and intradermal injection of PRP in the treatment of atrophic post-acne scars

BACKGROUND

Atrophic post-acne scars are common complications of acne. Many modalities are proposed, but each does not yield satisfactory clinical outcomes. To evaluate the therapeutic effect of PSP technique including dot peeling, subcision and intradermal injection of autologous platelet-rich plasma (PRP) for the treatment of atrophic post-acne scars.

PATIENTS AND METHODS

Twenty patients with different types of atrophic acne scars on the face were included. All patients received PSP technique in the form of dot peeling, then after 2 weeks, subcision and intradermal PRP injection were done simultaneously. PSP technique was performed for each patient every month for 3 months.

RESULTS

After 3 months of the last session, 30% of 20 patients had excellent improvement, 20% of patients had good improvement, 20% of patients had moderate improvement, and 30% of patients had mild improvement. There was statistically significant difference after treatment (p ≤ .001). Side effects were mild and tolerable and included erythema, ecchymosis, and hyperpigmentation. All types of scars showed significant improvement with no significant difference between them.

CONCLUSION

PSP technique was found to be a safe and cost-effective treatment option for atrophic acne scars.

PEGylated Platelet-Free Blood Plasma-Based Hydrogels for Full-Thickness Wound Regeneration

Objective: To develop a cost-effective and clinically usable therapy to treat full-thickness skin injuries. We accomplished this by preparing a viscoelastic hydrogel using polyethylene glycol (PEG)-modified platelet-free plasma (PEGylated PFP) combined with human adipose-derived stem cells (ASCs). Approach: PEGylated PFP hydrogels were prepared by polymerizing the liquid mixture of PEG and PFP±ASCs and gelled either by adding calcium chloride (CaCl₂) or thrombin. Rheological and in vitro studies were performed to assess viscoelasticity and the ability of hydrogels to direct ASCs toward a vasculogenic phenotype, respectively. Finally, a pilot study evaluated the efficacy of hydrogels±ASCs using an athymic rat full-thickness skin wound model. Results: Hydrogels prepared within the range of 11 to 27 mM for CaCl₂ or 5 to 12.5 U/mL for thrombin exhibited a storage modulus of ∼62 to 87 Pa and ∼47 to 92 Pa, respectively. The PEGylated PFP hydrogels directed ASCs to form network-like structures resembling vasculature, with a fourfold increase in perivascular specific genes that were confirmed by immunofluorescent staining. Hydrogels combined with ASCs exhibited an increase in blood vessel density when applied to excisional rat wounds compared with those treated with hydrogels (110.3 vs. 95.6 BV/mm²; p < 0.05). Furthermore, ASCs were identified in the perivascular region associated with newly forming blood vessels. Innovation: This study demonstrates that PFP modified with PEG along with ASCs can be used to prepare cost-effective stable hydrogels, at the bed-side, to treat extensive skin wounds. Conclusion: These results indicate that PEGylated plasma-based hydrogels combined with ASCs may be a potential regenerative therapy for full-thickness skin wounds.

Effectiveness of Autologous Platelet-Rich Plasma for the Healing of Ulcers after Endoscopic Submucosal Dissection

Background/Aims

Platelet-rich plasma (PRP) has been used for wound healing in various medical fields. The aim of this study was to evaluate the clinical efficacy and safety of local PRP injections after endoscopic submucosal dissection (ESD).

Methods

Patients were non-randomly divided into the following two groups: (1) control group in which patients were administered only an intravenous proton pump inhibitor (PPI), and (2) a study group in which patients were administered an intravenous PPI and a topical PRP injection. We assessed the reduction in the ulcer area and stage of the ulcer after the procedure (24 hours, 48 hours, and 28 days after endoscopic surgery).

Results

We enrolled 7 study and 7 control patients. In the study group, the rate of ulcer reduction was 59% compared to 52% in the control group (p=0.372), 28 days after ESD. There were 5 patients in the S stage and 2 patients in the H stage in the study group compared to no patient in the S stage and 7 patients in the H stage in the control group (p=0.05), 28 days after ESD. There were no serious complications in either group.

Conclusions

The local injection of PRP is a safe and effective procedure for ulcer healing after ESD.

Platelet-rich plasma and its utility in medical dermatology: A systematic review

The field of dermatology has seen numerous therapeutic innovations in the past decade with platelet-rich plasma (PRP), recently garnering significant interest in alopecia, acne scarring, and skin rejuvenation. In other conditions of dermatology, such as chronic wounds and vitiligo, PRP has been investigated but has received less attention. The objective of this literature review was to focus on conditions of medical dermatology and to consolidate the available evidence on PRP for the practicing dermatologist. This review evaluates the literature up to October 31, 2018, and a search was conducted in the PubMed database for "platelet-rich plasma," "platelet releasate," "platelet gel," "platelet-rich fibrin" or "PRP" and "dermatology," "skin," "cutaneous," "wound," or "ulcer." In total, 14 articles met the inclusion criteria for this review. In studies representing Levels of Evidence 1b-4 according to the Centre for Evidence-Based Medicine, Oxford, PRP significantly improved wound healing in chronic diabetic ulcers, venous ulcers, pressure ulcers, leprosy ulcers, acute traumatic wounds, and ulcers of multifactorial etiologies. Two studies also documented benefits of adjunctive PRP in stable vitiligo. In chronic wounds of multiple etiologies and vitiligo, PRP warrants further investigation because it represents a potential therapeutic adjunct or alternative with a favorable side effect profile.

Advances in surgical applications of growth factors for wound healing

Growth factors have recently gained clinical importance for wound management. Application of recombinant growth factors has been shown to mimic cell migration, proliferation, and differentiation in vivo, allowing for external modulation of the healing process. Perioperative drug delivery systems can enhance the biological activity of these growth factors, which have a very short in vivo half-life after topical administration. Although the basic mechanisms of these growth factors are well understood, most have yet to demonstrate a significant impact in animal studies or small-sized clinical trials. In this review, we emphasized currently approved growth factor therapies, including a sustained release system for growth factors, emerging therapies, and future research possibilities combined with surgical procedures. Approaches seeking to understand wound healing at a systemic level are currently ongoing. However, further research and consideration in surgery will be needed to provide definitive confirmation of the efficacy of growth factor therapies for intractable wounds.

Platelets and their biomimetics for regenerative medicine and cancer therapies

Platelets, circulating blood cells derived from megakaryocytes, play a key role in various physical activities, including coagulation, hemostasis, the body's innate immune response, and cancer metastasis. By taking advantage of their key traits, researchers have developed strategies to exploit platelets and platelet-mimicking nanoassemblies to treat a number of conditions, including wounds, cancers, and bacterial infections. Compared to traditional polymer, lipsosome, and inorganic nanoparticles-based delivery systems, platelets and platelet-mimicking vehicles hold many advantages. Among these are their enhanced circulation time, their large volumes and surface areas for drug loading or conjugation, and their inherent ability to target some diseases. In this review, we will highlight the recent progress made in the development of disease-targeting platelets- and platelet-mimicking-vehicles as therapeutic platforms.

Blood Plasma Derivatives for Tissue Engineering and Regenerative Medicine Therapies

Platelet-rich plasma (PRP) and its derivatives have been investigated and applied in regenerative medicine. The use of PRP as a supplement of cell culture media has consistently shown to potentiate stem cell proliferation, migration, and differentiation. In addition, the clinical utility of PRP is supported by evidence that PRP contains high concentrations of growth factors (GFs) and proteins which contribute to the regenerative process. PRP based therapies are cost effective and also benefit from the accessibility and safety of using the patient's own GFs. In the last years, a great development has been witnessed on PRP based biomaterials, with both structural and functional purposes. In this study we overview the most relevant PRP applications encompassing PRP based materials for tissue engineering and regenerative medicine. This review also summarizes the challenges in the fields of tissue engineering and regenerative medicine and provides a perspective on future directions.

Submucosal injection of platelet-rich plasma in endoscopic resection of large sessile lesions

AIM

To prospectively evaluate the efficacy of submucosal injection of platelet-rich plasma (PRP) on endoscopic resection of large sessile lesions.

METHODS

Eleven patients were submitted to endoscopic mucosal resection (EMR) with prior injection of PRP, obtained at the time of endoscopy. Patients were followed during 1 mo. The incidence of adverse events (delayed bleeding or perforation) and the percentage of mucosal healing (MHR) after 4 wk were registered.

RESULTS

EMR was performed in 11 lesions (46.4 mm ± 4 mm, range 40-70 mm). Delayed bleeding or perforation was not observed in any patient. Mean ulcerated area at baseline was 22.7 cm2 ± 11.7 cm2 whereas at week 4 were 2.9 cm2 ± 1.5 cm2. Patients treated with PRP showed a very high MHR after 4 wk (87.5%).

CONCLUSION

PRP is an easy-to-obtain solution with proven and favourable biological activities that could be used in advanced endoscopic resection.

Use of platelet-rich plasma to facilitate wound healing

Platelet-rich plasma (PRP) is widely used nowadays in different fields of medicine, affecting physiological processes including tissue regeneration. The use of PRP in maxillofacial surgical interventions and its efficiency in the improvement of postoperative wound healing were analysed. Patients undergoing plastic and reconstructive surgeries in the maxillofacial region were recruited: 50 patients were enrolled into a control group (received no PPRP injection) and 50 patients were enrolled into a treatment group, where PRP was applied during the surgical procedure. Evaluation of treatment outcomes was carried out by determination of IL-1β, TNFα, and IL-6 cytokines levels in the wound-drain fluid. The stages of wound healing were assessed by cytological analyses and ultrasound within a month period. The use of the PRP has substantially positive effects, contributing to the improvement of the healing process. In the treatment group, fibroblasts, macrophages, and collagen fibres appeared and their quantities increased earlier than when compared with control group patients. The concentration of IL-1β and TNFα in wound fluid on day 1 and day 5 after operation was higher for the treatment group as opposed to the control group, which was linked to the influence of PRP on inflammatory and granulation phases of the healing process. An ultrasound examination showed less oedema and infiltration in the tissues around the wound of the treatment group.

PEG-Plasma Hydrogels Increase Epithelialization Using a Human Ex Vivo Skin Model

In vitro cell culture methods are used extensively to study cellular migration, proliferation, and differentiation, which play major roles in wound healing but the results often do not translate to the in vivo environment. One alternative would be to establish an ex vivo model utilizing human discarded skin to evaluate therapies in a more natural setting. The purpose of this study was to institute such a model by creating ‘wounds’ in the center of a piece of discarded skin and treating them with three different biomaterials: collagen, polyethylene glycol (PEG)-fibrin, or PEG-platelet free plasma (PFP). Explants were cultured for 14 days with supernatant and microscopy images collected every 3 days to assess cytotoxicity and epithelialization. After 14 days, the explants were fixed, sectioned, and stained for cytokeratin-10 (CK-10), alpha-smooth muscle actin (α-SMA), and wheat germ (WG). Compared to controls, similar levels of cytotoxicity were detected for 12 days which decreased slightly at day 14. The PEG-PFP hydrogel-treated wounds epithelialized faster than other treatments at days 6 to 14. A 6-8 cell layer thick CK-10+ stratified epidermis had developed over the PEG-PFP hydrogel and cells co-stained by WG and α-SMA were observed within the hydrogel. An ex vivo model was established that can be used practically to screen different therapies exploring wound healing.

Platelet biology in regenerative medicine of skeletal muscle

Platelet-based applications such as platelet-rich plasma (PRP) and platelet releasate have gained unprecedented attention in regenerative medicine across a variety of tissues as of late. The rationale behind utilizing PRP originates in the delivery of key cytokines and growth factors from α-granules to the targeted area, which in turn act as cell cycle regulators and promote the healing process across a variety of tissues. The aim of the present review is to assimilate current experimental evidence on the role of platelets as biomaterials in tissue regeneration, particularly in skeletal muscle, by integrating findings from human, animal and cell studies. This review is composed of 3 parts: firstly, we review key aspects of platelet biology that precede the preparation and use of platelet-related applications for tissue regeneration. Secondly, we critically discuss relevant evidence on platelet-mediated regeneration in skeletal muscle focusing on findings from (i) clinical trials, (ii) experimental animal studies and (iii) cell culture studies; and thirdly, we discuss the application of platelets in the regeneration of several other tissues including tendon, bone, liver, vessels and nerve. Finally, we review key technical variations in platelet preparation that may account for the large discrepancy in outcomes from different studies. This review provides an up-to-date reference tool for biomedical and clinical scientists involved in platelet-mediated tissue regenerative applications.

Early intervention in scar management and cutaneous burns with autologous platelet-rich plasma

Burn management options are controversial and a multiple-handled issue. However, platelet-rich plasma is gaining interest in several medical fields. Dermatologist worldwide are already publishing some reports about its benefits and personal experiences in their practices. A 40-year-old female with a second-degree burn by VASER-type liposculpture was treated with platelet-rich plasma and followed up for 10 months. After treatment, she showed rapid improvement with an adequate cicatrization results. Some studies suggest that the use of platelet-rich plasma which contains cytokines and growth factors that participate in cellular repair and cellular differentiation, thus improving healing time and re-epithelization. We present the case of a patient with a second-degree burn that rapidly improved with autologous platelet-rich plasma.

A bioartificial dermal regeneration template promotes skin cell proliferation in vitro and enhances large skin wound healing in vivo

A novel bioartificial dermal regeneration template has been developed using platelet-rich plasma and acellular animal skin collagen sponge for the treatment of larger area and full thickness skin wounds. This platelet-rich plasma-collagen sponge keeps native skin structure and contains huge amounts of growth factors. The effect of this bioartificial dermal regeneration template was tested in vitro and in vivo via a mimic poor wound healing process by adding collagenase I into cell culture medium or the wound area. The in vitro experimental results indicated that the rat skin cells grew faster and produced more collagen in platelet-rich plasma-collagen sponge with collagenase than those treated either with collagen sponge plus collagenase, or collagenase, or control group without treatment. The in vivo experiments were performed by large rat skin wounds, 1.5 cm diameter, treated either with collagenase, or collagenase plus collagen sponge, or collagenase plus platelet-rich plasma-collagen sponge. The wound without treatment was used as a control. The wounds treated with collagenase-containing platelet-rich plasma-collagen sponge healed 4 times faster than the untreated wounds, 6 times faster than the collagenase treated wounds, 2.4 times faster than collagenase-containing collagen sponge treated wounds. The immunostaining indicated that the healed tissues in the wound areas treated with collagenase-containing platelet-rich plasma-collagen sponge were composed of collagen type I and collagen III with blood vessels and hair follicles. The results demonstrated that this collagenase-containing platelet-rich plasma-collagen sponge works as a bioartificial dermal regeneration template. The application of this collagenase-containing platelet-rich plasma-collagen sponge promotes the traumatic skin wound healing and permits the reconstitution of the inherent barrier functions of the skin.

The effect of mesenchymal stem cells combined with platelet-rich plasma on skin wound healing

INTRODUCTION

Mesenchymal stem cells (MSCs) are multipotent stem cells that have the potential of proliferation, high self-renewal, and the potential of multilineage differentiation. The differentiation potential of the MSCs in vivo and in vitro has caused these cells to be regarded as potentially appropriate tools for wound healing. After the burn, trauma or removal of the tumor of wide wounds is developed. Although standard treatment for skin wounds is primary healing or skin grafting, they are not always practical mainly because of limited autologous skin grafting.

EVIDENCE ACQUISITIONS

Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO), and Web of Science have been searched.

EVIDENCE SYNTHESIS

For clinical use of the MSCs in wound healing, two key issues should be taken into account: First, engineering biocompatible scaffolds clinical use of which leads to the least amount of side effects without any immunologic response and secondly, use of stem cells secretions with the least amount of clinical complications despite their high capability of healing damage.

CONCLUSION

In light of the MSCs' high capability of proliferation and multilineage differentiation as well as their significant role in modulating immunity, these cells can be used in combination with tissue engineering techniques. Moreover, the MSCs' secretions can be used in cell therapy to heal many types of wounds. The combination of MSCs and PRP aids wound healing which could potentially be used to promote wound healing.

Histopathologic Evaluation of Hyaluronic Acid and Plasma-Rich Platelet Injection into Rabbit Vocal Cords: An Experimental Study

Objective

Various materials are used by otolaryngologists for vocal cord injections in the management of vocal cord paralysis. An ideal injection material should be long-term effective, readily available, cheap, easy to prepare, have no donor morbidity, easy to use, biocompatible, resistant to resorption or migration, and easy to extract during revision. In this study, we aimed to see the histopathological effects of hyaluronic acid (HYA) and platelet-rich plasma (PRP) injections into the vocal cords of New Zealand rabbits.

Methods

PRP was injected into the right vocal cords of twelve rabbits, which was prepared from their serum (PRP group). HYA was injected into the left vocal cords of first six rabbits (numbered 1-6) (HYA group), and the left vocal cords of the other six rabbits (numbered 7-12) were followed with no intervention (control group). Two months later, histomorphological findings in the vocal cords were assessed by two experienced pathologists in seven parameters: chronic inflammation, mucosal atrophy, necrosis, neovascularization, fibrosis, foreign body reaction, and muscular atrophy. They were scored double-blinded as negative (0), mild (+1), moderate (+2), and severe (+3). Fisher's chi-square test was used to evaluate any statistical significance among the three groups.

Results

Chronic inflammation, mucosal atrophy, necrosis, foreign body reaction, and muscular atrophy parameters were scored as "0" for each preparate by both pathologists. For neovascularization and fibrosis, a stasistically significant difference was seen among the three groups (p<0.05). Neovascularization was increased in the PRP and HYA groups compared with the control group. No significant difference was observed in fibrosis when the groups were compared separately. After two months, two of the six vocal cords injected with HYA revealed HYA; however, none of the PRP-injected vocal cords showed PRP.

Conclusion

HYA and PRP can be safely injected into vocal cords. Our findings show that HYA is a biocompatible and safe injection material for clinical use. Only two of the six vocal cords showed HYA at the end of two months, suggesting that HYA is a short-term effective material. Similarly, PRP was also shown to be a short-term effective material and can be used in patients for testing purpose before using a long-term effective material. The advantages of PRP are that it is inexpensive, readily available, and completely inert as it is prepared from the subject itself.

Adipose-Derived Stromal Vascular Fraction Cells and Platelet-Rich Plasma: Basic and Clinical Implications for Tissue Engineering Therapies in Regenerative Surgery

Cell-based therapy and regenerative medicine offer a paradigm shift in regard to various diseases causing loss of substance or volume and tissue or organ damage. Recently, many authors have focused their attention on mesenchymal stem cells for their capacity to differentiate into many cell lineages. The most widely studied types are bone marrow mesenchymal stem cells and adipose derived stem cells (ADSCs), which display similar results. Based on the literature, we believe that the ADSCs offer advantages because of lower morbidity during the harvesting procedure. Additionally, platelet-rich plasma can be used in this field for its ability to stimulate tissue regeneration. The aim of this chapter is to describe ADSC preparation and isolation procedures, preparation of platelet-rich plasma, and the application of ADSCs in regenerative plastic surgery. We also discuss the mechanisms and future role of ADSCs in cell-based therapy and tissue engineering.

Management and effect of platelet-rich plasma on wound healing: small reality of Oglio Po Hospital

Platelet Rich Plasma (PRP) represents a relatively new approach in regenerative medicine. Its use is increasing in the treatment of a variety of orthopedic conditions, such as the management of acute wounds, chronic non-healing lesions, acceleration of bone formation, tendinopathy and chondropathy. The Orthopaedic Unit at Oglio Po Hospital uses PRP Gel in wound care since 2008. More than 70 patients have been treated with this procedure. The aim of this study is to show our patients outcome. We present 3 cases of severe traumatic wound treated with our PRP protocol. The patients had complete healing of the lesion with good aesthetic results.

Concise Review: The Use of Adipose-Derived Stromal Vascular Fraction Cells and Platelet Rich Plasma in Regenerative Plastic Surgery

Tissue engineering has emerged at the intersection of numerous disciplines to meet a global clinical need for technologies to promote the regeneration of tissues. Recently, many authors have focused their attention on mesenchymal stem/stromal cells (MSCs) for their capacity to differentiate into many cell lineages. The most widely studied cell types are bone marrow mesenchymal stem cells and adipose-derived stem cells (ASCs), which display similar results. Biomaterials, cells, and growth factors are needed to design a regenerative plastic surgery approach in the treatment of organ and tissue defects, but not all tissues are created equal. The aim of this article is to describe the advances in tissue engineering through the use of ASCs, platelet rich plasma, and biomaterials to enable regeneration of damaged complex tissue. Stem Cells 2017;35:117-134.

Efficacy of platelet-rich plasma as a shielding technique after endoscopic mucosal resection in rat and porcine models

BACKGROUND AND STUDY AIMS

The aims were to assess the efficacy of endoscopic application of Platelet-rich plasma (PRP) to prevent delayed perforation and to induce mucosal healing after endoscopic resections.

PATIENTS AND METHODS

Colonic induced lesions were performed in rats (n = 16) and pigs (n = 4). Animals were randomized to receive onto the lesions saline (control) or PRP. Animals underwent endoscopic follow-up. Thermal injury was assessed with a 1 - 4 scale: (1) mucosal necrosis; (2) submucosal necrosis; (3) muscularis propria necrosis; and (4) serosal necrosis

RESULTS

Saline treatment showed 50 % of mortality in rats (P = 0.02). Mean ulcerated area after 48 hours and 7 days was significantly smaller with PRP than with saline (0.27 ± 0.02 cm(2) and 0.08 ± 0.01 cm(2) vs. 0.56 ± 0.1 cm(2) and 0.40 ± 0.06 cm(2); P < 0.001). The incidence of thermal injury was significantly lower with PRP (1.25 ± 0.46) than in controls (2.25 ± 0.50); P = 0.006. The porcine model showed a trend toward higher mucosal restoration in animals treated with PRP than with saline at weeks 1 and 2 (Median area in cm(2): 0.55 and 0.40 vs. 1.32 and 0.79) CONCLUSIONS: Application of PRP to colonic mucosal lesions showed strong healing properties in rat and porcine models.

Healing of a soft tissue wound of the neck and jaw osteoradionecrosis using platelet gel

AIM

Bone osteoradionecrosis is a serious complication of radiation treatment. Current treatment approaches are not curative and treatment response is often poor leading to high social and healthcare costs.

CASE REPORT

We report on the first case of osteoradionecrosis with successful restitutio ab integro by repeated administration of platelet gel (PLT-gel) and surgery in a critically ill patient. The administration of PLT-gel during a severe septic episode helped regeneration of bone and soft tissues, shortening the hospital stay of the patient. It was also noted that following applications of PLT-gel, both the use of morphine and the numbers of infective episodes were reduced.

CONCLUSION

Additional studies are needed to confirm the promising effect of PLT-gel for the treatment of osteoradionecrosis.

Effect of Topical Platelet-Rich Plasma on Burn Healing After Partial-Thickness Burn Injury

BACKGROUND To investigate the effects of platelet-rich plasma on tissue maturation and burn healing in an experimental partial-thickness burn injury model. MATERIAL AND METHODS Thirty Wistar albino rats were divided into 3 groups of 10 rats each. Group 1 (platelet-rich plasma group) was exposed to burn injury and topical platelet-rich plasma was applied. Group 2 (control group) was exposed to burn injury only. Group 3 (blood donor group) was used as blood donors for platelet-rich plasma. The rats were killed on the seventh day after burn injury. Tissue hydroxyproline levels were measured and histopathologic changes were examined. RESULTS Hydroxyproline levels were significantly higher in the platelet-rich plasma group than in the control group (P=.03). Histopathologically, there was significantly less inflammatory cell infiltration (P=.005) and there were no statistically significant differences between groups in fibroblast development, collagen production, vessel proliferations, or epithelization. CONCLUSIONS Platelet-rich plasma seems to partially improve burn healing in this experimental burn injury model. As an initial conclusion, it appears that platelet-rich plasma can be used in humans, although further studies should be performed with this type of treatment.

The application of platelet-rich plasma in the treatment of deep dermal burns: A randomized, double-blind, intra-patient controlled study

Platelet-rich plasma (PRP) is a fraction of blood with a platelet concentration above baseline. When platelets get activated, growth factors involved in wound healing are released. The application of PRP has shown good results in wound care, however, up to date no substantial research has been performed on the effect of PRP in burn treatment. This randomized double blind intra-patient controlled study investigates the effect of autologous PRP on wound healing in burns that require surgery with a meshed split skin graft (SSG). Fifty-two patients with various areas of deep dermal to full thickness burns, receiving surgery with a SSG were included after informed consent. Comparable study areas A and B (intra-patient) were appointed, randomized and either treated with a SSG and PRP or with a SSG alone. At day 5 to 7 postoperative, the epithelialization and graft take rate were assessed. Three, six, and twelve months postoperative, follow-up measurements were performed in the form of POSAS-questionnaires, DermoSpectroMeter, and Cutometer measurements. There was no statistically significant difference between the mean take rate nor the mean epithelialization rate at day 5-7 between the PRP-treated and control areas. However, PRP-treated wound areas showed more often better or equal epithelialization and take rates at day 5-7 than the standard treated areas. Minor effects were also seen in the reoperated and early operated subgroups. At 3, 6, and 12 months postoperative, POSAS scores from the patients and the observers, Dermaspectro-, and Cutometer measurements did not depict a significant difference between the PRP and standard treated areas. Concluding, the addition of PRP in the treatment of burn wounds did not result in improved graft take and epithelialization, nor could we demonstrate better scar quality. There was, however, a considerable variation in our clinical population.

Early Intervention with Highly Condensed Adipose-Derived Stem Cells for Complicated Wounds Following Filler Injections

BACKGROUND

A rise in cosmetic procedures has seen the use of fillers become more prevalent. Complications resulting from use of fillers have prompted introduction of various medical and surgical interventions. Recently, stem cell therapies have become more widely used as a new treatment option for tissue repair and regeneration.

METHODS

We utilized adipose-derived stem cells (ASCs) for tissue regeneration in patients with filler-related complications such as necrosis. All 12 patients were treated with ASCs and some patients had additional treatment. After relief of symptoms, wound surface area was compared in terms of pixel numbers and scar condition was evaluated using the Vancouver Scar Scale (VSS).

RESULTS

In general, we achieved satisfactory resolution of filler-related complications in a short period of time without serious side effects. The average number of days from stem cell treatment to symptom relief was 7.3 days. The proportion of wound surface area from photographic record was 4.39 % before treatment, decreasing considerably to 1.01 % following treatment. Last, the VSS showed almost all patients scored below 3, with two patients receiving scores of 7 and 8; the average score was 2.78 (range from 0 to 8).

CONCLUSIONS

ASCs are a new treatment option for post-filler injection wounds such as necrosis. Using stem cells, we were able to obtain satisfactory results in a short period of time without complications requiring surgical procedures. We suggest stem cell injections could be used as the first option for treatment of complications from filler injections.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Effect of platelet-rich plasma combined with demineralised bone matrix on bone healing in rabbit ulnar defects

INTRODUCTION

This study evaluates the effect of autologous platelet-rich plasma (PRP) combined with xenogeneic demineralised bone matrix (DBM) on bone healing of critical-size ulnar defects (2-2.5 times the ulnar diameter) in New Zealand White rabbits.

METHODS

Critical-size defects were created unilaterally in the ulna of 36 rabbits, while keeping the contralateral limb intact. They were divided into three groups. In Group A, the defect was filled with autologous PRP and in Group B, with autologous PRP combined with DBM; in Group C, the defect remained empty. The rabbits were euthanised 12 weeks postoperatively. Radiological, biomechanical and histological assessments were carried out and statistical analysis of the results was performed.

RESULTS

Group B had significantly higher radiological and histological scores than Groups A and C. Defects in Group B showed significant new bone formation, whereas there was minimal or no new bone formation in Groups A and C. Only specimens in Group B showed macroscopic bone union. Biomechanical evaluation of the treated and intact contralateral limbs in Group B showed significant differences.

CONCLUSION

In this study, statistically significant enhancement of bone healing was found in critical-size defects treated with PRP and DBM, as shown by radiological findings, gross assessment, and biomechanical and histopathological results. Defects in the two other groups remained unbridged. Therefore, PRP was effective only when it was used in combination with a bone graft.

Should we use platelet-rich plasma as an adjunct therapy to treat "acute wounds," "burns," and "laser therapies": A review and a proposal of a quality criteria checklist for further studies

Platelet-rich plasma seems to help wound healing. The goal of this review is to determine if the adjunction of platelet-rich plasma enhances the clinical outcome of acute wounds, burns, and laser therapies. A PubMed and Cochrane library search was performed by two reviewers with the senior author as a consultant. Medical Subject Headings search terms used were the following: ["Platelet-rich plasma" OR "Platelet gel" OR "Platelet growth factor"] AND ["Acute wound" OR "Wound" OR "Burn" OR "Laser"]. We included controlled studies assessing the clinical outcome of acute wounds, burns, and laser therapies treated by platelet-rich plasma. Nine randomized controlled studies, six prospective controlled studies, and two retrospective controlled studies were included. Regarding acute wounds, three randomized controlled trials found a statistical benefit regarding either the healing time, the return back to work time, the quality of life, or the pain and three prospective controlled studies found a statistical difference regarding the velocity of healing. Platelet-rich plasma decreased the intensity or duration of erythema after laser therapy in four randomized studies. Regarding the long-term outcome of laser therapies, two studies found a statistical benefit and two others did not. Platelet-rich plasma accelerates acute wound healing and decreases erythema after laser therapies. Its use on burns has not been enough studied.

Platelet Gel in a Non-Regenerating Cryosurgery-Induced Skin Wound in an Old Patient: A Case Report

OBJECTIVE

To report on the clinical benefits of platelet gel application in a non-regenerating skin wound.

CLINICAL PRESENTATION AND INTERVENTION

An 84-year-old man presented with a severe wound with a regular circumference in the frontal region which resulted in a complete loss of epidermis and dermis. The skin lesion, induced by cryosurgery used to remove a basal-cell carcinoma, had previously been treated with a dermal substitute application (Integra®). After the failure of the skin graft, the patient was treated using a platelet gel therapeutic protocol which achieved the complete healing of the injured area.

CONCLUSION

This case showed the clinical efficacy of using platelet gel in this elderly patient in whom the dermal substitute graft had been ineffective.