Platelet-rich Plasma Gel Research Articles

Interpenetrating Hydrogel Networks Enhance Mechanical Stability, Rheological Properties, Release Behavior and Adhesiveness of Platelet-Rich Plasma.

Platelet-rich plasma (PRP) has attracted much attention for the treatment of articular cartilage defects or wounds due to its intrinsic content of growth factors relevant for tissue repair. However, the short residence time of PRP in vivo, due to the action of lytic enzymes, its weak mechanical properties and the consequent short-term release of bioactive factors has restricted its application and efficacy. The present work aimed at designing new formulation strategies for PRP, based on the use of platelet concentrate (PC)-loaded hydrogels or interpenetrating polymer networks, directed at improving mechanical stability and sustaining the release of bioactive growth factors over a prolonged time-span. The interpenetrating hydrogels comprised two polymer networks interlaced on a molecular scale: (a) a first covalent network of thermosensitive and biodegradable vinyl sulfone bearing p(hydroxypropyl methacrylamide-lacate)-polyethylene glycol triblock copolymers, tandem cross-linked by thermal gelation and Michael addition when combined with thiolated hyaluronic acid, and (b) a second network composed of cross-linked fibrin. The PC-loaded hydrogels, instead, was formed only by network (a). All the designed and successfully synthesized formulations greatly increased the stability of PRP in vitro, leading to significant increase in degradation time and storage modulus of PRP gel. The resulting viscoelastic networks showed the ability to controllably release platelet derived growth factor and transforming growth factr β1, and to improve the tissue adhesiveness of PRP. The newly developed hydrogels show great potential for application in the field of wound healing, cartilage repair and beyond.

Sophisticated polycaprolactone/gelatin nanofibrous nerve guided conduit containing platelet-rich plasma and citicoline for peripheral nerve regeneration: In vitro and in vivo study

Peripheral nerve injury (PNI) is a devastating condition that may result in loss of sensory function, motor function, or both. In the present study, we construct an electrospun nerve guide conduit (NGC) based on polycaprolactone (PCL) and gelatin filled with citicoline bearing platelet-rich plasma (PRP) gel as a treatment for PNI. The NGCs fabricated from PCL/Gel polymeric blend using the electrospinning technique. The characterizations demonstrated that the fabricated nanofibers were straight with the diameter of 708 ± 476 nm, the water contact angle of 78.30 ± 2.52°, the weight loss of 41.60 ± 6.94% during 60 days, the tensile strength of 5.31 ± 0.97 MPa, and the young's modulus of 3.47 ± 0.10 GPa. The in vitro studies revealed that the PCL/Gel/PRP/Citi NGC was biocompatible and hemocompatible. The in vivo studies conducted on sciatic nerve injury in rats showed that the implantation of PCL/Gel/PRP/Citi NGC induced regeneration of nerve tissue, demonstrated with histopathological assessments. Moreover, the sciatic function index (SFI) value of −30.3 ± 3.5 and hot plate latency time of 6.10 ± 1.10 s revealed that the PCL/Gel/PRP/Citi NGCs recovered motor and sensory functions. Our findings implied that the fabricated NGC exhibited promising physicochemical and biological activates favorable for PNI treatment.

Effects of wet-to-dry bandages on second intention healing of surgical wounds on the skin of goats.

Objectives:This study aimed to examine the effects of wet-to-dry bandages for the treatment of surgical wounds in goats.Materials and Methods:Three types of bandages, i.e., the calcium alginate gel, the homogenous platelet-rich plasma (PRP) gel dressing, and saline dressing, were used to promote the healing process for the management of wounds. Artificial circular wounds were created and treated with bandages to evaluate their effects on the wound healing process in 12 goats. The morphological parameters, i.e., diameters (cm), duration of healing, and wound contraction (cm), were evaluated to differentiate the postoperative sequelae on wound healing process up to day 30 in three different treatment groups of goats. Tissue specimens from the wounds were examined histopathologically on 1st, 3rd, 7th, and 30th postoperative days. Finally, the obtained data were analyzed using the Statistical Package for the Social Sciences 19 software.Results:The current study revealed that the contraction diameter was higher in calcium alginate gel and PRP gel treated group when compared to the saline dressing group. Aggregation of immunoreactive cells (neutrophils, macrophages, and lymphocytes), collagen fiber bundles among the cells, and proliferation of blood vessels were observed in the epidermis of calcium alginate gel, PRP gel treated and saline dressing wounds, which promote the healing process of wounds. In visual inspection, the number of reactive cells and proliferation of blood vessels were higher in the calcium alginate gel and PRP gel treated group than the saline dressing.Conclusion:In terms of epithelialization, epidermal characteristics, neovascularization, and infiltration of immunoreactive cells, the calcium alginate gel and the homogenous PRP gel dressings showed the best healing performance. Therefore, the present study suggests that clinicians could consider the calcium alginate gel dressing and homogenous PRP gel dressing as beneficial for wound care.

Is platelet-rich plasma improves the anastomotic healing in hyperthermic intraperitoneal chemotherapy with oxaliplatin: an experimental rat study.

PurposeHyperthermic intraperitoneal chemotherapy (HIPEC) is a novel treatment option for peritoneal surface malignancies. Due to cytotoxic effects of chemotherapeutic agents, anastomosis healing can be impaired and lead to leakage rates higher than conventional intestinal surgery. In this experimental study, we aimed to investigate the effects of platelet-rich plasma (PRP) on colonic anastomosis in rats that received HIPEC with oxaliplatin.MethodsThirty rats were divided into 3 groups. Group 1 was determined as control group and hyperthermic saline perfusion was performed after colon anastomosis. In group 2, colon anastomosis then hyperthermic oxaliplatin perfusion was performed. In the last group, the colonic anastomosis was enhanced by PRP gel and then hyperthermic oxaliplatin perfusion was performed. All the rats were reoperated on postoperative day 7 and anastomotic bursting pressure values were recorded. Tissue samples were taken for hydroxyproline assay and histopathological examination.ResultsControl group had higher anastomotic bursting pressure value than group 2 and group 3 (P < 0.001). There were significant differences in anastomotic bursting pressure between groups 2 and 3 (P < 0.001). Group 2 had significantly lower hydroxyproline levels than group 3 and control group (P < 0.001). Histopathological examination revealed that PRP application reduced inflammatory response.ConclusionPRP application on colonic anastomosis improves anastomotic healing and can reduce anastomosis related complications and stoma creation; though further clinical studies are needed.

Adipose-derived stem cells embedded in platelet-rich plasma scaffolds improve the texture of skin grafts in a rat full-thickness wound model

Skin grafts are widely used in plastic and reconstructive surgery. Increasing the early vascularization of skin grafts is a key factor in improving skin grafting. In this study, we use platelet-rich plasma gel as an adipose-derived stem cell scaffold to assist the growth of rat skin grafts. ADSCs were successfully isolated and seeded into the PRP gel. Using a Lewis rat model, we found the PRP gel + ADSCs significantly improved the properties of the transplanted skin grafts, increased the skin thickness and improved the collagen arrangement. PRP gel + ADSCs promoted skin neovascularization by elevating the expression of the vascularization factors VEGF, BFGF and PDGFB. Taken together, our study indicated that ADSCs combined with PRP have a potentiation effect on improving skin grafts by promoting angiogenesis, providing an innovative approach and a theoretical basis for its clinical application.

Clinical study of local injection of autologous platelet-rich plasma in treatment of diabetic foot ulcer

To investigate the effectiveness of local injection of autologous platelet-rich plasma (PRP) in treatment of diabetic foot ulcer. Between October 2017 and October 2018, 90 diabetic foot ulcer patients who met the selection criteria were randomly divided into 3 groups: PRP injection group (group A, PRP was injected and hydrogel dressing covered the wounds), PRP covered group (group B, PRP gel and hydrogel dressing covered the wounds), and the control group (group C, hydrogel dressing covered the wounds), 30 cases in each group. There was no significant difference in gender, age, injured side, disease duration, preoperative glycosylated hemoglobin, wound size, and Wagner grading between groups (P>0.05). The frequency of treatments and hospitalization day in all groups and the total amount of PRP application in groups A and B were recorded. The wound healing condition was recorded during the treatment, and the wound healing rate was calculated at 3 months after the first debridement. The frequency of treatments in groups A, B, and C were (10.2±0.8), (11.4±0.6), (12.5±0.5) times, respectively. The total amount of PRP application of groups A and B were (306±24) and (342±18) mL, respectively. There was no significant difference in the frequency of treatments and the total amount of PRP application between groups (P>0.05). The hospitalization days of groups A, B, and C were (40.5±1.8), (62.1±2.3), and (88.6±1.4) days, respectively, showing significant differences between groups (P<0.05). In the course of treatment, the necrosis and exudation of the wounds gradually reduced, the areas of wounds gradually reduced; and the above conditions of group A were significantly better than groups B and C, and group B was better than group C. At 3 months after the first debridement, the wound healing rates of groups A, B, and C were 93.2%±0.8%, 52.1%±1.1%, and 21.3%±1.3%, respectively, with significant differences between groups (P<0.05). PRP can effectively promote the repair of diabetic foot ulcer. The effectiveness of local injection of PRP is superior to the local coverage.

Functionalising Collagen-Based Scaffolds With Platelet-Rich Plasma for Enhanced Skin Wound Healing Potential.

Porous collagen-glycosaminoglycan (collagen-GAG) scaffolds have shown promising clinical results for wound healing; however, these scaffolds do not replace the dermal and epidermal layer simultaneously and rely on local endogenous signaling to direct healing. Functionalizing collagen-GAG scaffolds with signaling factors, and/or additional matrix molecules, could help overcome these challenges. An ideal candidate for this is platelet-rich plasma (PRP) as it is a natural reservoir of growth factors, can be activated to form a fibrin gel, and is available intraoperatively. We tested the factors released from PRP (PRPr) and found that at specific concentrations, PRPr enhanced cell proliferation and migration and induced angiogenesis to a greater extent than fetal bovine serum (FBS) controls. This motivated us to develop a strategy to successfully incorporate PRP homogeneously within the pores of the collagen-GAG scaffolds. The composite scaffold released key growth factors for wound healing (FGF, TGFβ) and vascularization (VEGF, PDGF) for up to 14 days. In addition, the composite scaffold had enhanced mechanical properties (when compared to PRP gel alone), while providing a continuous upper surface of extracellular matrix (ECM) for keratinocyte seeding. The levels of the factors released from the composite scaffold were sufficient to sustain proliferation of key cells involved in wound healing, including human endothelial cells, mesenchymal stromal cells, fibroblasts, and keratinocytes; even in the absence of FBS supplementation. In functional in vitro and in vivo vascularization assays, our composite scaffold demonstrated increased angiogenic and vascularization potential, which is known to lead to enhanced wound healing. Upon pro-inflammatory induction, macrophages released lower levels of the pro-inflammatory marker MIP-1α when treated with PRPr; and released higher levels of the anti-inflammatory marker IL1-ra upon both pro- and anti-inflammatory induction when treated with the composite scaffold. Finally, our composite scaffold supported a co-culture system of human fibroblasts and keratinocytes that resulted in an epidermal-like layer, with keratinocytes constrained to the surface of the scaffold; by contrast, keratinocytes were observed infiltrating the PRP-free scaffold. This novel composite scaffold has the potential for rapid translation to the clinic by isolating PRP from a patient intraoperatively and combining it with regulatory approved scaffolds to enhance wound repair.

Differences in results of infrabony pocket treatment with addition of platelet rich fibrin and platelet rich plasma gel in DFDBA bone graft

Treatment of infrabony pocket makes use of bone graft material demineralized freeze dried bone allograft (DFDBA) from different individuals which has undergone demineralization process and it is osteoinductive. Enhancement of growth factor was done by adding platelet rich fibrin (PRF) and platelet rich plasma (PRP). PRP is activated with an addition of calcium chloride CaCl2) to form gel. The method used to apply the bone grafting material is open flap debridement OFD). This research aimed to reveal the differences in the results of infrabony pocket treatment using PRF and PRP gel with an addition of DFDBA. The sample was taken from 20 infrabony pocket points divided into 2 groups, 10 infrabony pocket were treated with OFD+DFDBA+PRF and the other were treated with OFD+DFDBA+PRP gel. Pocket depth (PD) was measured on the baseline and the first and third month after treatment. Alveolar bone height was measured using cone beam computed tomography (CBCT) radiograph on the baseline to the third month after treatment. The results of this research showed that there was difference in the results of infrabony pocket treatment using PRF and PRP gel with an addition of DFDBA which could be observed from a reduction in PD from the baseline, month 1 and month 3 as well as reduction in alveolar bone height from the baseline to month 3. This research concluded that infrabony pocket treatment PRF application yields better results than PRP gel application in terms of PD and alveolar bone height reduction.

A randomized controlled trial of effectiveness of platelet-rich plasma gel and regular dressing on wound healing time in pilonidal sinus surgery: Role of different affecting factors

BackgroundThe aim of this study was to assess the possible association between different factors such as age, sex, antibiotic consumption duration, angiogenesis and pain and “acceleration of wound healing” in pilonidal sinus patients after treating with platelet-rich plasma (PRP). MethodsIn this clinical trial, 110 patients were randomly divided into treatment arm and control group. After surgery, control group underwent classic wound dressing and the treatment arm experienced PRP gel therapy. Before achieving complete healing, wound incisional biopsy was performed in order to evaluate angiogenesis. During the study, other data such as pain and antibiotic consumption duration were also collected. Wound healing time of pilonidal sinus disease was analyzed using Extended and Stratify Cox model. Data were analyzed using R and STATA software. p<0.05 were considered statistically significant. ResultsThe average wound volume was calculated 41.9 ± 8.01 cc in the controls and 42.35 ± 10.81 in the treatment arm group. The mean of healing time was 8.7 ± 1.18, 4.8 ± 0.87 weeks for control and treatment arm, respectively. There was a significant and strong negative association between healing time and wound volume (p<0.01). Moreover, a significant negative association was found between pain duration and angiogenesis (p<0.001), a strong positive significant association was found between healing time of the treatment arms (p<0.01), and the rate of wound healing for participants treated with PRP gel was 37.2 times more than that of controls. ConclusionAuthors hope for these finding to help the future researches to more thoroughly focus on the mentioned factors in order to find a suitable strategy for wound healing using PRP.

Use of Platelet-Rich Plasma for the Improvement of Pain and Function in Rotator Cuff Tears: A Systematic Review and Meta-analysis With Bias Assessment

Background: Many clinical trials have investigated the use of platelet-rich plasma (PRP) to treat rotator cuff–related abnormalities. Several meta-analyses have been published, but none have focused exclusively on level 1 randomized controlled trials. Purpose: To assess the efficacy of PRP for rotator cuff–related abnormalities and evaluate how specific tendon involvement, the inclusion of leukocytes, and the use of gel/nongel formulations affect pain and functional outcomes. Study Design: Systematic review and meta-analysis. Methods: The literature was screened following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Baseline, short-term, and long-term data were extracted for the Constant score, University of California, Los Angeles (UCLA) score, visual analog scale (VAS) for pain, retear rate, Simple Shoulder Test (SST), and American Shoulder and Elbow Surgeons (ASES) score. The 100-point modified Coleman Methodology Score (CMS) was used to assess methodological quality. Funnel plots and the Egger test were used to screen for publication bias, and sensitivity analysis was performed to evaluate the effect of potential outliers. Results: A total of 18 level 1 studies were included in this review, 17 (1116 patients) of which could be included in quantitative analysis. The mean modified CMS was 79.4 ± 10.39. The Constant scores of patients who received PRP were significantly better short term (weighted mean difference [WMD], 2.89 [95% CI, 0.89-4.90]; P < .01) and long term (WMD, 2.66 [95% CI, 1.13-4.19]; P < .01). The VAS scores were significantly improved short term (WMD, –0.45 [95% CI, –0.75 to −0.15]; P < .01). Sugaya grade IV and V retears in PRP-treated patients were significantly reduced long term (odds ratio [OR], 0.34 [95% CI, 0.20-0.57]; P < .01). In PRP-treated patients with multiple tendons torn, there were reduced odds of retears (OR, 0.28 [95% CI, 0.13-0.60]; P < .01). Patients who received leukocyte-rich PRP had significantly better Constant scores compared with the leukocyte-poor PRP group, but there was no difference in VAS scores. Patients receiving PRP gel reported higher Constant scores compared with the controls, whereas those receiving nongel PRP treatments did not, although there was no difference in VAS scores. Long-term odds of retears were decreased, regardless of leukocyte content (leukocyte-poor PRP: OR, 0.36 [95% CI, 0.16-0.82]; leukocyte-rich PRP: OR, 0.32 [95% CI, 0.16-0.65]; all P < .05) or usage of gel (nongel: OR, 0.42 [95% CI, 0.23-0.76]; gel: OR, 0.17 [95% CI, 0.05-0.51]; all P < .01). Conclusion: Long-term retear rates were significantly decreased in patients with rotator cuff–related abnormalities who received PRP. Significant improvements in PRP-treated patients were noted for multiple functional outcomes, but none reached their respective minimal clinically important differences. Overall, our results suggest that PRP may positively affect clinical outcomes, but limited data, study heterogeneity, and poor methodological quality hinder firm conclusions.

Effectiveness of autologous platelet-rich plasma gel in the treatment of hard-to-heal leg ulcers: a randomised control trial.

Regenerative medicine products such as autologous platelet-rich plasma (autologous PRP) gel may speed up the process of healing. Clinical studies show promising results in the treatment of diabetic foot ulcers (DFUs), however there is lack of scientific evidence of autologous PRP effectiveness in treating leg ulcers of other aetiology. This study evaluates the effectiveness of autologous PRP gel in the treatment of hard-to-heal leg ulcers compared with existing conventional treatment. A prospective, randomised controlled, open-labelled clinical trial was carried out between 2014 and 2018. An eight-week study protocol was chosen or until 100% wound re-epithelialisation was observed. Wound size reduction, granulation tissue formation, microbiological wound bed changes and safety were evaluated. A total of 69 patients (35 in the autologous PRP group and 34 in the control group) were included in the study; 25.71% of the autologous PRP group and 17.64% of control group had ulcers completely re-epithelialised (p>0.05). Wound size reduction in the autologous PRP group was 52.35% and 33.36% in the control group (p=0.003). The autologous PRP group showed superiority over conventional treatment in wound bed coverage with granulation (p=0.001). However, more frequent wound contamination was observed at the end of treatment in the autologous PRP group (p=0.024). No severe adverse events were noted during the study. Both treatment methods were considered equally safe. Topical application of autologous PRP gel in leg ulcers of various aetiology show beneficial results in wound size reduction and induces the granulation tissue formation. However, it is associated with more frequent microbiological wound contamination.

The effects of the use of platelet-rich plasma gel on local recurrence in an animal model of human fibrosarcoma

BackgroundPlatelet-rich-plasma (PRP) is largely used, thanks to its properties, as wound therapy after surgical resection. Several studies and clinical findings have demonstrated that the PRP can accelerate the regeneration and the repair of tissues through the action of the platelet-derived growth factors.Material and methodsOur study aimed to investigate the effects of PRP-gel on the rate of tumor relapse by using a mouse model of Human Fibrosarcoma (HF). The radical resection of tumors of mice was conducted under fluorescence-guidance (FGR) by using MacroFluo microscope, after a primary tumor removal with bright-light surgery (BLS).ResultsIt was found that the lesion recurrence and the tumor growth were reduced in mice treated with PRP observed in each group of treatment (50%) after 30 days from tumor excision, respect to controls (without statistical significance; p = 0.12). The histopathological and immune-histochemical analysis did not report differences in cellular morphology between the tumors of control and PRP-treated mice.ConclusionOur data suggest that PRP-gel, used as an adjuvant treatment for the stimulation of tissue repair and speed up recovery, can impair tumor growth and slow the tumor.

The effects of platelet‐rich‐plasma gel application to the colonic anastomosis in hyperthermic intraperitoneal chemotherapy: An experimental rat model

Hyperthermic intraperitoneal chemotherapy (HIPEC) has cytotoxic effects on tumour cells but also negative impacts on anastomotic healing. Platelet-rich-plasma (PRP) is used for wound care but data about effects on gastrointestinal anastomosis are limited. In this experimental study, we aimed to investigate the effects of PRP application on colon anastomosis in rats those received HIPEC with cisplatin. Five rats were sacrificed to obtain PRP gel. Thirty rats were divided into three groups; Group 1: control group, Group 2: colon anastomosis and HIPEC with cisplatin, and Group 3: colon anastomosis enhanced by PRP and HIPEC with cisplatin. The rats were re-operated on postoperative day seven and anastomotic bursting pressure (ABP) was recorded. Also, tissue samples were taken for hydroxyproline assessment and histopathological examination. There were significant differences in ABP between Groups 2 and 3, and also those groups had lower ABP compared with the control group. Group 3 had significantly higher hydroxyproline levels and had better histopathological findings than group 2. According to our findings, we suggest that PRP application improves the anastomotic healing by increasing anastomotic bursting pressure, hydroxyproline levels, and decreasing inflammatory response. Further clinical studies are needed to prove our hypothesis.

The use of autologous platelet-rich plasma gel increases wound healing and reduces scar development in split-thickness skin graft donor sites

The treatment of donor sites after split-thickness skin grafting (STSG) is a routine operation step, and complications at the donor site due to improper operation and care are unwelcome. This study evaluates whether the use of platelet-rich plasma (PRP) applied at the STSG area promotes wound healing and improves scar development. Clinical data of 30 patients who underwent STSG operations between January 2016 and January 2017 for various reasons were retrospectively analyzed. These 30 patients received two treatments and the data were summed up in two groups: the PRP group, which was the study group, included patients who received traditional petrolatum gauze dressing with PRP gel at the donor sites. The petrolatum gauze group, which was the control group, received only petrolatum gauze care without PRP gel. The time and frequency of dressing change were comparable between the two groups, and the mean wound healing times in the PRP group and petrolatum gauze group were 13.89 ± 4.65 and 17.73 ± 5.06 days, respectively, and the difference was statistically significant (p < 0.05). In addition, the total Vancouver scar scale (VSS) scores of the PRP group at 4, 12 and 52 weeks were 6.41 ± 0.77, 4.42 ± 0.43 and 2.41 ± 0.39, respectively, which were statistically significantly lower (p < 0.05) than those of the control group at 7.67 ± 0.64, 6.28 ± 0.62 and 4.29 ± 0.64, respectively. The use of PRP gel can promote wound healing, relieve scar development and alleviate pain at the donor site after STSG.

Clinical effects of autologous platelet-rich plasma gel in the repair of chronic wounds

Objective: To explore the clinical application effects of autologous platelet-rich plasma gel in the repair of various chronic wounds. Methods: From January 2015 to January 2018, 76 patients with chronic wounds were admitted to our unit, with 39 men and 37 women, aged 28 to 75 (52±6) years. Before the operation, areas of wounds ranged from 2.0 cm×0.5 cm to 17.0 cm×5.0 cm, depths of wounds ranged from 1 to 6 cm, areas of wounds substrate ranged from 3 cm×3 cm to 17 cm×8 cm, and volumes of deep cavities ranged from 7 to 55 mL. All patients received operation 2 to 7 days after admission. Autologous platelet of 220-250 mL was collected from each patient by single extraction to make platelet-rich plasma of 10-50 mL. The cavity was filled completely by injection of platelet-rich plasma gel for 1-3 times. Wounds were sutured directly or covered by local flaps or other materials according to the conditions of wounds, and the unclosed wounds in primary stage were treated by continuous vacuum sealing drainage (VSD). Ultrasound, CT, or magnetic resonance imaging was performed to detect the healing of cavity after the operation. The healing of wound and repair of cavity after the operation and during follow-up were observed. Results: Wounds in 39 patients were closed directly after primary operation. Among them, wounds of 36 patients were healed completely, and wounds of the other 3 patients were healed completely after second debridement and topical filling of platelet-rich plasma gel. The cavities in 35 patients were filled with granulation tissue after treatment of platelet-rich plasma gel for 1-3 times combined with VSD, and the wounds were healed after skin grafting or flap transplantation. The treatment of wounds discontinued in the other 2 patients after treatment of platelet-rich plasma gel for once. Postoperative follow-up was lost in 7 patients. During follow-up of 2 and/or 4 months after the primary operation, wounds were healed well with no recurrence, and cavities were filled with fibrous tissue. Conclusions: Autologous platelet-rich plasma gel has advantages in treating chronic wounds, including a large amount by single extraction, flexible use mode, ability to fully fill the complex cavity, high surgical safety, and mild secondary injury. It's a new choice for repair of chronic wounds in clinic.

Biostimulation of venous chronic ulcers with platelet-rich plasma gel and biocompatible membranes of chitosan and alginate: A pilot study

Abstract Venous ulcers are a common disease caused by circulatory insufficiency, having as characteristics slow healing and therefore a difficult treatment. Consequently, this disease has a high impact at personal, professional and social levels, representing large costs for both patients and healthcare system. The aim of the present pilot study was to evaluate the effectiveness of an alternative treatment for this specific type of wound, based on the use of autologous platelet-rich plasma gel (PRP) combined with biocompatible porous membranes produced with the polysaccharides chitosan (C) and alginate (A). The applicability, security and healing efficacy of this treatment was evaluated in four patients suffering from venous ulcers with an at least 6-month of evolution that did not heal after conventional treatments. The clinical evolution analysis during the treatment was performed by periodic measurement of the lesions area for an average of 5.4 months. The results attained showed that the use of this treatment led to completed reduction in the ulcers area as well as to pain decrease. Hence, the combination between autologous PRP gel and chitosan-alginate (CA) porous membranes could be a useful alternative to treat chronic skin ulcers in humans.

Arthroscopic knotless tape bridging with autologous platelet-rich fibrin gel augmentation: functional and structural results

ABSTRACTBackground: Rotator cuff repairs remain a source of iterative ruptures and disappointing functional results. In this goal, autologous platelet-rich plasma (PRP) has been used to improve tendon healing. This prospective study assessed the contribution of fully autologous gel concentrates (platelet concentrates and thrombin) on healing after cuff repair.Methods: A consecutive series of 69 patients who underwent primary arthroscopic knotless tape bridging primary cuff repair of supraspinatus tear were evaluated. Two groups were created (A: n = 32, B: n = 37). Autologous PRP gel, obtained preoperatively by PRP mixed with autologous thrombin extracted from platelet-poor plasma, was injected at bone-tendon interface at end of repair in group A. Gel structure avoided evacuation of concentrates with irrigation liquid. Constant, QuickDash and Visual Analogue Scale (VAS) scores were assessed pre-operatively and then successively post-operatively. Healing was assessed by 24-month control MRI according to Sugaya’s classification. Sugaya 3, 4, and 5 were considered as iterative ruptures.Results: Average age was 56 years (±7.8). Mean follow-up was similar: 28.6 months (±3.3) vs 32.4 months (±9.4). Mean preoperative Constant was similar: 53.4 (±3.4) vs 54.6 (±5.4). Group A patients received 3.5 ml (±1.5 ml) of autologous PRP gel. No specific complication of injection was found. We observed higher trend in favour of PRP without significativity: Constant 86.7 (±11.1) vs 81.6 (±14.4), p = 0.11; VAS: 0.6 (±0.3) vs 1.1 (±0.9), p = 0.13; Forward flexion: 139.5° (±14.4°) vs 137.7° (± 16.5°), p = 0.63; Strength score: 17.6 vs 14.8, p = 0.66; QuickDash: 6.2 (±5.3) vs 8.2 (±6.9), p = 0.32 . On MRI, 90% (n = 3) of repairs were healed in group A versus 86% (n = 5) in group B.Conclusion: In this preliminary study, the group treated with autologous PRP gel showed a trend towards better clinical and radiological results. These results were not significant at the last follow-up. Only significantly higher clinical results were found at 3 months.Study design: Therapeutic prospective comparative cohort study; Level of evidence III.

Controlled Delivery of Stem Cell-Derived Trophic Factors Accelerates Kidney Repair After Renal Ischemia-Reperfusion Injury in Rats.

Renal disease is a worldwide health issue. Besides transplantation, current therapies revolve around dialysis, which only delays disease progression but cannot replace other renal functions, such as synthesizing erythropoietin. To address these limitations, cell‐based approaches have been proposed to restore damaged kidneys as an alternative to current therapies. Recent studies have shown that stem cell‐derived secretomes can enhance tissue regeneration. However, many growth factors undergo rapid degradation when they are injected into the body in a soluble form. Efficient delivery and controlled release of secreting factors at the sites of injury would improve the efficacy in tissue regeneration. Herein, we developed a gel‐based delivery system for controlled delivery of trophic factors in the conditioned medium (CM) secreted from human placental stem cells (HPSCs) and evaluated the effect of trophic factors on renal regeneration. CM treatment significantly enhanced cell proliferation and survival in vitro. Platelet‐rich plasma (PRP) was used as a delivery vehicle for CM. Analysis of the release kinetics demonstrated that CM delivery through the PRP gel resulted in a controlled release of the factors both in vitro and in vivo. In an acute kidney injury model in rats, functional and structural analysis showed that CM delivery using the PRP gel system into the injured kidney minimized renal tissue damage, leading to a more rapid functional recovery when compared with saline, CM, or vehicle only injection groups. These results suggest that controlled delivery of HPSC‐derived trophic factors may provide efficient repair of renal tissue injury. stem cells translational medicine 2019;8:959&970

Antimicrobial Effect of Platelet Rich Plasma and Platelet Gel against Staphylococcus aureus Isolated from Surgical Site Infections: An In Vitro Study

Antimicrobial Effect of Platelet Rich Plasma and Platelet Gel against Staphylococcus aureus Isolated from Surgical Site Infections: An In Vitro Study

Effect of Autologous Platelet-Rich Plasma Gel on Skin Flap Survival.

BackgroundSkin flap grafting is one of the most common tissue transplantations for wound repair and organ reconstruction. Thus, improving the survival rate of the transplanted skin flap is important. Platelet-rich plasma (PRP) is an autologous platelet concentrate obtained from whole blood. It has been widely used in repairing tissue defects. Considering that the PRP gel has similar biological characteristics, this study used PRP gel for skin flap transplantation.Material/MethodsPRP gel from Sprague-Dawley (SD) rats was prepared and the growth factor concentration was determined. A rat skin flap model was established to evaluate the survival rate of skin flap. Morphologic evaluation was also done.ResultsWe found that the PRP gel increased the survival rate of the skin flap. In addition, it reduces the inflammation response in skin flap transplantation and has better effects in terms of generating new soft tissue.ConclusionsThe effectiveness PRP gel in skin flap transplantation is satisfactory. The possible mechanisms by which PRP gel promotes the survival of the skin flap includes platelets, growth factors, immune activity factor, and fibrin. PRP could be a new clinical method for promoting skin flap survival.