Platelet-rich plasma loaded with antibiotics as an affiliated treatment for infected bone defect by combining wound healing property and antibacterial activity.

To be faced with an infected bone defect and the need to accelerate bone union while controlling infection is a welcome challenge for orthopedists. Platelet-rich plasma (PRP) has been applied in tissue defects given their composition of growth factors however the weak antibacterial effects have limited the use of PRP in the clinical setting. Therefore, the aim of this study was to explore the feasibility of using PRP in a local antibiotic delivery system (PADS) with the characteristics of promoting wound healing of bone infection. PADS was prepared with the addition of antibiotics or no antibiotics as control after PRP was prepared by a two-step centrifugation procedure. Antibacterial tests showed zones of inhibition produced by antibiotics were not significantly different with antibiotics combined with PRP. HPLC analysis demonstrated that about 60% of the total vancomycin (VAN) and ceftazidime (CAZ) dose were released within 10 min, then the release rate gradually decreased. However, 90% clindamycin was released within 10 min. Interestingly, above 10 times the minimum inhibitory concentration was presented after 72 h. Additionally, ELISA and morphology studies of PADS indicated that loaded antibiotics could reduce the PRP-released growth factor concentration and disturb the structure of platelet-fibrin beams and fibrin network in a dose-dependent manner. Fortunately, the lower dose of antibiotics maintained their anti-microbial effect, meanwhile growth factors released from PADS, the structure of platelet-fibrin beams, fibrin network remained unaffected. In addition, a patient experiencing infected bone defect receiving this PADS treatment achieved union within the 15-month follow-up. Therefore, this novel PADS approach might represent a potential therapy for patients who have sustained infected bone defects.

Blood component separation of pathogen-reduced whole blood by the PRP method produces acceptable red cells but platelet yields and function are diminished.

BACKGROUND: This study evaluated blood components processed by the platelet rich plasma (PRP) method from fresh whole blood (FWB) treated with a pathogen reduction technology (PRT). The effects of storage temperature on PRT treated platelet concentrates (PCs) were also examined. STUDY DESIGN AND METHODS: PRT was performed using riboflavin and ultraviolet light on FWB in citrate phosphate dextrose anticoagulant. Following PRT, red blood cells (RBCs), PCs, and plasma for fresh frozen plasma (FFP), were isolated by sequential centrifugation. RBCs were stored at 4°C, FFP at -80°C, and PC at 22°C or at 4°C. Components were assayed throughout their storage times for blood gases, chemistry and CBC, hemostatic function as well as platelet (PLT) and RBC integrity. RESULTS: Component processing following PRT resulted in a significant drop in platelet recovery. Most PRT-PC bags fell below AABB guidelines for platelet count. PRT-PC also showed a decrease in clot strength and decreased aggregometry response. Platelet caspases were activated by PRT. Storage at 4°C improved platelet function. In PRT-FFP, prothrombin time and partial thromboplastin time (PT and aPTT) were prolonged; factors V, VII, VIII, and XI, protein C, and fibrinogen were significantly decreased. Free hemoglobin was elevated two-fold in PRT-RBC. CONCLUSION: Blood components isolated by the PRP method from PRT-treated WB result in a high percentage of PC that fail to meet AABB guidelines. FFP also shows diminished coagulation capacity. However, PRT-RBC are comparable to control-RBC. PRT-WB retains acceptable hemostatic function but alternatives to the PRP method of component separation may be more suitable.

Evaluation of the in vivo wound healing potential of the lipid fraction from activated platelet-rich plasma.

Previous in vitro studies suggest a direct relevance for the peptide-free lipid fraction (LF) of platelet-rich plasma (PRP) in biological mechanisms related to wound healing. However, there are no scientific reports to date on the wound healing activities of this lipid component in vivo. Thus, the present study provides a scientific evaluation for the wound healing potential of the lipid portion of the activated PRP. For the wound healing activity assessment, in vivo full-thickness excisional wounds were created on the dorsal skin of Sprague-Dawley rats. Lipid extract from pooled PRP was applied topically to the wounds on 0, 3, and 7 days after injury. Histological assessment of epidermal and dermal regeneration, granulation tissue thickness and angiogenesis by Sirius red and Masson's trichrome staining, in addition to immunohistochemical staining for transforming growth factor beta-1 (TGF-ß1), collagen type I (COL I), and collagen type III (COL III) were performed on skin biopsies at 3, 7 and 14 days. The total histological scores of the LF group were significantly higher than the 25% dimethylsulfoxide-control group. According to the immunohistochemical staining, the observed expression changes for TGF-ß1, COL I and III at 3, 7, and 14 days after wounding were significantly better in the study group than the control group. Furthermore, COL I/III ratio in the lipid extract-treated group at day 14 was much higher than that of the control group. Meanwhile, analysis of the data also indicated that the LF has less positive effects on all evaluated parameters than PRP. From the present data, it could be concluded that the peptide-free LF of PRP has potent wound healing capacity in vivo for cutaneous wounds, although not as much as that of PRP. Strengthening our understanding of the wound healing potential of lipid components of PRP and platelet-derived lipid factors may provide new avenues for improving the healing process of a wound with elevated protease activity.

Evaluation of platelet function in essential thrombocythemia under different analytical conditions.

Background. Studies of platelet aggregation (PA) in essential thrombocythemia (ET) reported contrasting results, likely due to differences in analytical conditions.Objective. We investigated platelet aggregation using different techniques and analytical conditions.Patients and Methods. PA was studied by light-transmission aggregometry (LTA) in platelet-rich plasma (PRP) and impedance aggregometry in PRP and whole blood (WB). ADP, collagen, thrombin receptor activating peptide (TRAP-14) and adrenaline were used as agonists. Since ET patients (n = 41) were on treatment with aspirin (100 mg/d), healthy controls (n = 29) were given aspirin (100 mg/d) for 5 days before testing: therefore, thromboxane A2-independent PA was tested in all subjects. Blood samples were collected in citrate (C) [low Ca2+] or lepirudin (L) [physiological Ca2+]; platelet count was adjusted to 250 x 109/L in a set of C-PRP (adjusted C-PRP) and left unmodified in the other samples.Results. Results of PA in 17 ET patients who were poor responders to aspirin (high serum thromboxane B2 levels) were not included in the analysis. With LTA, PA in ET was lower than in controls in adjusted C-PRP and normal in native C-PRP and L-PRP. With impedance aggregometry, PA in L-PRP and L-WB tended to be higher in ET than in controls. Platelet serotonin and ADP contents were reduced in ET. The percentages of circulating platelets expressing P-selectin and platelet-leukocyte hetero-aggregates were higher in ET.Conclusions. Analytical conditions dramatically affect in vitro PA of ET patients, which appears defective under the least physiological conditions and normal/supranormal under conditions that are closer to the physiological.

Comparison of the GPVI inhibitors losartan and honokiol.

Losartan and honokiol are small molecules which have been described to inhibit aggregation of platelets by collagen. Losartan has been proposed to block clustering of GPVI but not to affect binding of collagen. Honokiol has been reported to bind directly to GPVI but only at a concentration that is three orders of magnitude higher than that needed for inhibition of aggregation. The mechanism of action of both inhibitors is so far unclear. In the present study, we confirm the inhibitory effects of both agents on platelet aggregation by collagen and show that both also block the aggregation induced by the activation of CLEC-2 or the low affinity immune receptor FcγRIIa at similar concentrations. For GPVI and CLEC-2, this inhibition is associated with a reduction in protein tyrosine phosphorylation of multiple proteins including Syk. In contrast, on a collagen surface, spreading of platelets and clustering of GPVI (measured by single molecule localisation microscopy) was not altered by losartan or honokiol. Furthermore, in flow whole-blood, both inhibitors suppressed the formation of multi-layered platelet thrombi at arteriolar shear rates at concentrations that hardly affect collagen-induced platelet aggregation in platelet rich plasma. Together, these results demonstrate that losartan and honokiol have multiple effects on platelets which should be considered in the use of these compounds as anti-platelet agents.

PLGA-PEG Nanoparticles Show Minimal Risks of Interference with Platelet Function of Human Platelet-Rich Plasma.

The expansion of nanotechnology for drug delivery applications has raised questions regarding the safety of nanoparticles (NPs) due to their potential for interacting at molecular and cellular levels. Although polymeric NPs for drug delivery are formulated using FDA-approved polymers such as lactide- and glycolide-based polymers, their interactions with blood constituents, remain to be identified. The aim of this study was to determine the impact of size-selected Poly-lactide-co-glycolide-polyethylene glycol (PLGA-PEG) NPs on platelet activity. The NPs of 113, 321, and 585 nm sizes, were formulated and their effects at concentrations of 0-2.2 mg/mL on the activation and aggregation of platelet-rich plasma (PRP) were investigated. The results showed that NPs of 113 nm did not affect adenosine diphosphate (ADP)-induced platelet aggregation at any NP concentration studied. The NPs of 321 and 585 nm, at concentrations ≥0.25 mg/mL, reduced ADP-activated platelet aggregation. The platelet activation profile remained unchanged in the presence of investigated NPs. Confocal microscopy revealed that NPs were attached to or internalised by platelets in both resting and activated states, with no influence on platelet reactivity. The results indicate minimal risks of interference with platelet function for PLGA-PEG NPs and that these NPs can be explored as nanocarriers for targeted drug delivery to platelets.

The effects of aging, diabetes mellitus, and antiplatelet drugs on growth factors and anti-aging proteins in platelet-rich plasma.

As the aged population continues to markedly increase worldwide, the incidences of diabetes mellitus (DM) and cardiovascular disease (CVD) are increasing. In this study, we investigated the effects of aging, DM, and antiplatelet drugs on growth factors and anti-aging proteins in platelet-rich plasma (PRP). The study participants were classified into the following four groups: Group A, healthy individuals aged ≤45 years; Group B, healthy individuals aged >45 years; Group C, DM patients aged >45 years; and Group D, CVD patients aged >45 years taking antiplatelet drugs. The concentrations of epidermal growth factor (EGF), fibroblast growth factor (FGF)-2, platelet-derived growth factor (PDGF)-AA, PDGF-AB/BB, vascular endothelial growth factor (VEGF)-A, tissue inhibitor of metalloproteinase 2 (TIMP2), insulin-like growth factor 1 (IGF-1), growth differentiation factor (GDF)11, and clusterin in PRP samples were determined to analyze the effects of aging, DM, and antiplatelet drugs. Overall, the concentrations of IGF-1, TIMP2, and clusterin did not vary significantly between the four groups. The concentrations of PDGF-AB/BB (P = 0.010), VEGF-A (P = 0.000), and GDF11 (P = 0.026) were significantly different between Group A and Group B. Further, the concentrations of EGF (P = 0.000) and GDF11 (P = 0.000) were significantly different between Groups B and C. The concentrations of EGF (P = 0.001), VEGF-A (P = 0.000), and GDF11 (P = 0.002) significantly differed between Groups A and C. The concentrations of FGF-2 (P = 0.048), PDGF-AA (P = 0.03), and GDF11 (P = 0.001) were significantly different between Groups B and D. The concentrations of PDGF-AB/BB (P = 0.032), VEGF-A (P = 0.010), and GDF11 (P = 0.02) significantly differed between Groups A and D. We found that PRP contains high concentrations of the growth factors, TIMP2 and GDF11. Aging, DM, and antiplatelet drugs can decrease the concentration of some growth factors and GDF11, which weakens the regenerative capacity and anti-aging effects of PRP and reduces the quality of PRP.

Evaluation of the Newly Developed Adenosine Diphosphate-Induced Platelet Aggregation Level System in Aggregometer on Automated Coagulation Analyzer.

BACKGROUND: Light transmission aggregometry (LTA) is the gold standard for platelet function assessment. The automated coagulation analyzer from Sysmex that performs LTA offers the advantage of being a walk-away technology. Recently, a new parameter "ADP-induced platelet aggregation level (APAL)" was developed to support the interpretation of results. APAL is calculated as a score from 0.0 to 10.0 based on platelet aggregation patterns with 1 and 10 µM adenosine diphosphate (ADP). Here, the basic performance of the newly developed APAL system and comparison with the maximum aggregation rate of ADP (ADP-MA) was evaluated. METHODS: The within-run precision was calculated by conducting five replicate analyses of the platelet-rich plasma (PRP) from healthy volunteers and 0.05 µM of cangrelor-spiked PRP. Cangrelor is a P2Y12 inhibitor that does not require liver CYP activation. The reference interval was calculated from the results of 67 healthy volunteers. The effect of the antiplatelet P2Y12 agent was evaluated using several concentrations of cangrelor. A comparative study was performed using 103 PRP samples with different levels of aggregation. Each test was analyzed with both APAL and ADP-MA. RESULTS: The percentage coefficient of variation in within-run precision was within 7% for APAL and 10 µM ADP-MA. Reference interval of APAL and 10 µM ADP-MA was 7.1 - 10.0 and 80.0 - 99.2%, respectively. APAL signifi-cantly decreased with the addition of 0.02 µM cangrelor, while 10 µM ADP-MA was barely affected. A significant correlation was observed between APAL and 10 µM ADP-MA (r = 0.94; p < 0.0001). CONCLUSIONS: The newly developed APAL system exhibited an acceptable performance. APAL score showed a good correlation with ADP-MA and was adequate to detect the weak effect of P2Y12 inhibitors. APAL is a new platelet aggregation scoring system with the potential to monitor the effects of P2Y12 inhibitor over a wide range.

In Vitro Antithrombotic Properties of Salmon (Salmo salar) Phospholipids in a Novel Food-Grade Extract.

Marine and salmon polar lipids (PLs) extracted by conventional extractions with non-food-grade solvents (CE-salmon-PLs) possess antithrombotic bioactivities against platelet-activating factor (PAF) and thrombin. Similar effects of food-grade-extracted (FGE) marine PLs have not yet been reported. In this study, food-grade solvents were used to extract PLs from Irish organic farmed salmon (Salmo salar) fillets (FGE-salmon-PLs), while their antithrombotic bioactivities were assessed in human platelets induced by platelet aggregation agonists (PAF/thrombin). FGE-salmon-PLs were further separated by thin layer chromatography (TLC) into lipid subclasses, and the antithrombotic bioactivities of each subclass were also assessed. LC-MS was utilized to elucidate the structure-activity relationships. FGE-salmon-PLs strongly inhibited PAF-induced platelet aggregation, while their relevant anti-thrombin effects were at least three times more potent than the previously reported activities of CE-salmon-PLs. TLC-derived lipid fractions corresponding to phosphatidylcholines (PC) and phosphatidylethanolamines (PE) were the most bioactive lipid subclasses obtained, especially against thrombin. Their LC-MS analysis elucidated that they are diacyl- or alkyl-acyl- PC and PE moieties baring ω3 polyunsaturated fatty acids (PUFA) at their sn-2 position, such as eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). Our results concerning the potent antithrombotic effects of FGE-salmon-PLs against both PAF and thrombin pathways strongly suggest that such food-grade extracts are putative candidates for the development of novel cardioprotective supplements and nutraceuticals.

Impacts of resveratrol versus platelet-rich plasma for treatment of experimentally lithium-induced thyroid follicular cell toxicity in rats. A histological and immunohistochemical study.

Lithium (Li) is used for the treatment and prophylaxis of mental disorders, associated with many serious hazards. Resveratrol (RSV) has various beneficial therapeutic effects. Platelet-rich plasma (PRP) is a new promising curative tool. This study aimed to assess the impacts of RSV versus PRP on lithium-induced thyroid follicular cell toxicity in adult male rats. Forty-nine adult male rats were divided into four groups: group I: control rats; group II: lithium-treated rats; group III: lithium- and resveratrol-treated rats; group IV: lithium and PRP-treated rats. Thyroid specimens were taken and processed for histological and immunohistochemical methods. Morphometrical studies and statistical analysis were done. Group II showed distorted thyroid follicles, significantly increased collagen fibers, and highly positive P53 immunostaining (P < 0.01). Ultrastructural examination showed dilated rough endoplasmic reticulum and damaged mitochondria. Groups III and IV exhibited significant amelioration of the histological and electron microscopic changes mentioned previously. PRP remedy was more effective than RSV for treatment of Li-induced thyroid follicular cell toxicity.

Comparison of efficacy of eight treatments for plantar fasciitis: A network meta-analysis.

The objective of this network meta-analysis (NMA) was to assess the pain relief performance of eight different plantar fasciitis therapies, including nonsteroidal anti-inflammatory medications, corticosteroid injections (CSs), autologous whole blood, platelet-rich plasma (PRP), extracorporeal shockwave therapy (ESWT), ultrasound therapy (US), botulinum toxin A (BTX-A), and dry needling (DN). Published prospective or randomized controlled trials (RCTs) as for the above eight therapies were identified by searching CNKI, PubMed, and Embase. Mean difference (MD) and 95% credible intervals (CrIs) of visual analogue scale (VAS) were used to evaluate multiaspect comparisons. The ranking result was obtained by utilizing surface under cumulative ranking curve (SUCRA). Node-splitting plots were conducted to assess the consistency between direct and indirect evidence. Egger's test and funnel plots were performed to examine publication bias. Forty-one trials with a total of 2,889 cases were involved in this NMA. In terms of 1-month VAS, only ESWT turned out to be of better efficacy than placebo (MD = -3.3; CrI: [-5.3, -1.1]). No statistically significant difference was found between pair-wise comparisons concerning 2-month VAS. ESWT also demonstrated better efficacy as for 3-month results (MD = -2.7; CrI: [-4.2, -1.3]). Besides, CSs was significantly better than placebo as well in 3-month results (MD = -2.1; CrI: [-4.1, -0.19]). With regard to 6-month VAS results, ESWT performed better than placebo (MD = -3.0; CrI: [-5.0, -0.51]). According to the SUCRA, ESWT ranked the first as for all seven outcomes. ESWT might be the optimal treatment. In addition, BTX-A and PRP were considered as suboptimal.

Polyurethane/Gelatin Nanofibrils Neural Guidance Conduit Containing Platelet-Rich Plasma and Melatonin for Transplantation of Schwann Cells.

The current study aimed to enhance the efficacy of peripheral nerve regeneration using a biodegradable porous neural guidance conduit as a carrier to transplant allogeneic Schwann cells (SCs). The conduit was prepared from polyurethane (PU) and gelatin nanofibrils (GNFs) using thermally induced phase separation technique and filled with melatonin (MLT) and platelet-rich plasma (PRP). The prepared conduit had the porosity of 87.17 ± 1.89%, the contact angle of 78.17 ± 5.30° and the ultimate tensile strength and Young's modulus of 5.40 ± 0.98 MPa and 3.13 ± 0.65 GPa, respectively. The conduit lost about 14% of its weight after 60 days in distilled water. The produced conduit enhanced the proliferation of SCs demonstrated by a tetrazolium salt-based assay. For functional analysis, the conduit was seeded with 1.50 × 104 SCs (PU/GNFs/PRP/MLT/SCs) and implanted into a 10-mm sciatic nerve defect of Wistar rat. Three control groups were used: (1) PU/GNFs/SCs, (2) PU/GNFs/PRP/SCs, and (3) Autograft. The results of sciatic functional index, hot plate latency, compound muscle action potential amplitude and latency, weight-loss percentage of wet gastrocnemius muscle and histopathological examination using hematoxylin-eosin and Luxol fast blue staining, demonstrated that using the PU/GNFs/PRP/MLT conduit to transplant SCs to the sciatic nerve defect resulted in a higher regenerative outcome than the PU/GNFs and PU/GNFs/PRP conduits.

Combination Therapy with DETA/NO and Clopidogrel Inhibits Metastasis in Murine Mammary Gland Cancer Models via Improved Vasoprotection.

Vascular endothelial dysfunction and platelet activation play a key role in tumor metastasis, and therefore, both of these processes are considered important therapeutic targets in cancer. The aim of our studies was to analyze antimetastatic activity of combination therapy using nitric oxide donor DETA/NO and antiplatelet drug clopidogrel. Nitric oxide acts as a vasoprotective mediator, while clopidogrel inhibits ADP-mediated platelet aggregation. 4T1-luc2-tdTomato cell line transplanted intravenously (i.v.) and 4T1 cell line transplanted orthotopically were used as metastatic mammary gland cancer models. Moreover, antiaggregation action of compounds was tested ex vivo on the blood samples taken from breast cancer patients. We have shown that in selected dosage regimes, DETA/NO combined with clopidogrel significantly reduced lung metastatic foci formation in an i.v. model, and such inhibition was transiently observed also in an orthotopic model. The antimetastatic effect was correlated with a significant increase of prostacyclin (PGI2) metabolite and reduction of endothelin-1, sE-selectin, sI-CAM, and TGF-ß plasma levels as well as decreased V-CAM expression on the endothelium. Combination therapy decreased fibrinogen binding to the resting platelets at the early stage of tumor progression (day 14). However, at the later stages (days 21 and 28), the markers of platelet activation were detected (increased JON/A antibody bound, P-selectin level, binding of fibrinogen, and vWf). Decreased aggregation as well as a lower release of TGF-ß were detected in platelets incubated ex vivo with compounds tested from metastatic breast cancer patients. Although combination therapy increases E-cadherin, the increase of N-cadherin and α-SMA in tumor tissue was also observed. The results showed that at the early stages of tumor progression, combined therapy with DETA/NO and clopidogrel improves vasoprotective and antiplatelet activity. However, in advanced tumors, some adverse effects toward platelet activation can be observed.

Effects of pH and concentration of sodium citrate anticoagulant on platelet aggregation measured by light transmission aggregometry induced by adenosine diphosphate.

The 2013 ISTH-SSC guidelines for the standardization of light transmission aggregometry (LTA) were largely based on expert consensus, as studies directly comparing LTA methodologies were lacking. We experimentally tested the cogency of ISTH-SSC recommendations pertaining to use of anticoagulant, in particular whether: (1) buffered citrate (BC) is preferable to unbuffered citrate (C); (2) the two recommended concentrations of sodium citrate (109 and 129 mM) are equivalent in terms of platelet aggregation (PA). Blood from 16 healthy volunteers was collected into BC and C (109 and 129 mM). PA was measured by LTA in platelet-rich plasma (PRP) stimulated by adenosine diphosphate (ADP) (2 µM) immediately after PRP preparation and up to 4 hr after blood collection; pH and platelet counts in PRP were measured in parallel. pH in PRP increased with time up to about 8 for all anticoagulants, although it was lower in BC than in C at all times. In BC, PA was lower at 45 min, but equivalent at all other times. PA was higher and more stable in sodium citrate 109 mM than in 129 mM at all times. The extent of PA did not change for up to 2 hr after blood collection, and subsequently dramatically decreased. In contrast with ISTH-SSC recommendations, (1) BC does not show advantages compared to C; (2) 109 mM citrate is preferable to 129 mM, because it better supports PA; and (3) LTA studies should be completed within 2 hr of blood collection, instead of the recommended 4 hr.

[The effects of different activators on the release curve of human platelet-rich plasma].

Objective: To compare and analyze the effects of different activators on the release curve of TGF-ß(1) and PDGF-AB in platelet rich plasma(PRP). Methods: A total of 36 ml peripheral venous blood was obtained from 10 healthy adult volunteers, and the PRP was made by secondary centrifugation. The platelet activator was made by bovine thrombin 1 000 U in 1 ml 10% calcium chloride solution. The Thrombin-PRP group was made by PRP and the activator in a ratio of 10∶1.The Calcium chloride-PRP group was made in a ratio of 10∶1 by PRP and 10% calcium chloride solution instead. The fresh whole blood(whole blood group) and inactived PRP(PRP group) were used as the control groups. The 4 groups were incubated in warm water of 37 ℃ for 0, 1, 8, 24,72 and 168 h. A quantitative sandwich enzyme-linked immunosorbent assays(ELISA) was used to examine the amount of TGF-ß(1) and PDGF-AB in different time points of each group. The release curves of TGF-ß(1) and PDGF-AB were based on afore-mentioned data, and then comparisons of the release curves of TGF-ß(1) and PDGF-AB in different groups were performed by repeated measurement variance analysis. Results: (1)The levels of TGF-ß(1) and PDGF-AB in the whole blood group and the PRP group continued to increase within 168 h. PRP immediately formed into a gel after mixture with thrombin combined and calcium chloride, and the concentrations of TGF-ß(1) and PDGF-AB reached the peak in 1 h after activation; increased from (42±21)ng/ml and (77±18)ng/ml to (84±21)ng/ml and (124±35)ng/ml, respectively, and then decreased gradually. The release curve was direct and rapid. The PRP became a gel state in approximate 1 h after mixture with calcium chloride, and the concentrations of TGF-ß(1) and PDGF-AB were slowly rising and remained high at 168 h. (2)The AUC(0-168h) of TGF-ß(1) and PDGF-AB in the PRP group was higher than that in the whole blood group (all P<0.05) , and the AUC(0-168h) of TGF-ß(1) in the Calcium chloride-PRP group was higher than that in the Thrombin-PRP group(Z=-2.26, P<0.05).However, there was no significant difference in the AUC(0-168h) of PDGF-AB between the Calcium chloride-PRP group and the Thrombin-PRP group(Z=-1.512, P=0.131). Conclusion: Using calcium chloride as activator can get a higher release concentration of TGF-ß(1) and PDGF-AB and a longer release time, with the largest area under the curve.

Platelet-Rich Plasma for the Treatment of Clean Diabetic Foot Ulcers.

BACKGROUND: Diabetic foot ulcer is considered as a major health problem that predisposes to limb amputation. Among the different methods to achieve ulcer healing, platelet-rich plasma (PRP) gel is gaining popularity. It is thought to stimulate wound closure by providing essential growth factors for healing. This study aims to evaluate the value of autologous PRP gel in the treatment of diabetic ulcers. METHODS: The study included 56 patients of both sex from 18 to 80 years, with clean chronic diabetic foot ulcers divided into 2 equal groups. The first group was treated by antiseptic ointment dressing, and the second group was treated by autologous platelet gel. PRP together with thrombin were prepared by centrifugation at each dressing session. Thrombin and calcium chloride were used to activate the PRP. The formed platelet gel was applied to the wound twice weekly. RESULTS: Statically significant increase in healing rate was found in the PRP-treated group, and complete healing was achieved in 86% of them in comparison to 68% of the control group. In the study group, rate of healing per week was greater during the first 8 weeks and starts to decline afterward. The use of platelet gel showed a lower rate of wound infection. CONCLUSIONS: Autologous platelet gel is more effective than the local antiseptic dressing in terms of healing rate and prevention of infection in clean diabetic ulcers.

A systematic review and meta-analysis of platelet-rich plasma versus corticosteroid injections for plantar fasciopathy.

PURPOSE: To determine whether platelet-rich plasma (PRP) injections are associated with improved pain and function scores when compared with corticosteroid injections for plantar fasciopathy. METHODS: A systematic review of published literature was performed for studies comparing PRP injections and corticosteroid injections for plantar fasciopathy. Studies were assessed using the Cochrane Risk of Bias Tool and the Newcastle Ottawa Scale (NOS). The primary endpoint was pain and function score at three and six month follow-up. Sensitivity analysis was performed for high quality studies and randomised studies. RESULTS: Ten studies totalling 517 patients were included. Seven studies were randomised. All studies included patients who had failed conservative measures and excluded patients with systemic illness and other causes of foot pain. Studies reported outcomes using the visual analogue score (VAS) and American Orthopaedic Foot and Ankle Score (AOFAS). At 3-month follow-up, PRP injections were associated with improved VAS scores (standard mean difference [SMD], -0.66; 95% CI, -1.3 to -0.02; p = 0.04) and AOFAS scores (SMD, 1.87; 95% CI, 0.16-3.58; p = 0.03). At 6-month follow-up, there was no difference in VAS score (SMD, -0.66; 95% CI, -1.65 to 0.3; p = 0.17) or AOFAS scores (SMD, 1.69; 95% CI, -1.06 to 4.45; p = 0.23). No studies reported adverse event rates or cost analysis. There was no difference in pain or function score at one, six- or 12-month follow-up. Sensitivity analyses of high-quality studies showed no differences between the PRP and steroid group at any of the follow-up points. CONCLUSIONS: PRP injections are associated with improved pain and function scores at three month follow-up when compared with corticosteroid injections. Information regarding relative adverse event rates and cost implications is lacking. Further, large-scale, high-quality, randomised controlled trials with blinding of outcome assessment and longer follow-up are required.

Use of the arthroereisis screw with tendoscopic delivered platelet-rich plasma for early stage adult acquired flatfoot deformity.

PURPOSE: Early stage adult acquired flatfoot deformity (AAFD) is traditionally treated with osteotomy and tendon transfer. Despite a high success rate, the long recovery time and associated morbidity are not sufficient. This study aims to evaluate the functional and radiological outcomes following the use of the arthroereisis screw with tendoscopic delivered PRP for early stage AAFD. METHODS: Patients with stage IIa AAFD who underwent the use of the arthroereisis screw with tendoscopic delivered PRP with a minimum follow-up time of 24 months were retrospectively evaluated. Clinical outcomes for pain were evaluated with the Foot and Ankle Outcomes Score (FAOS) and Visual Analog Score (VAS). Radiographic deformity correction was assessed using weight-bearing imaging. RESULTS: Thirteen patients (13 feet) with mean follow-up of 29.5 months were included. The mean age was 37.3 years (range, 28-65 years). FAOS-reported symptoms, pain, daily activities, sports activities, and quality of life significantly improved from 52.1, 42.6, 57.6, 35.7, and 15.4 pre-operatively to 78.5, 68.2, 83.3, 65.0, and 49.6 post-operatively, respectively (p < 0.05). Statistically significant radiographic improvements (lateral talus first metatarsal angle, calcaneal pitch, and cuneiform to ground distance) were also observed between the pre- and post-operative images. CONCLUSIONS: This study elucidates the successful implementation of a less invasive approach to stage IIa AAFD. Through the use of a subtalar arthroereisis screw, PTT tendoscopy, and PRP injection, clinical and radiographic outcomes were improved.

Platelet-rich plasma for the treatment of bone defects: from pre-clinical rational to evidence in the clinical practice. A systematic review.

PURPOSE: The treatment of large bone defects represents a significant challenge for orthopaedic surgeons. In recent years, biologic agents have also been used to further improve bone healing. Among these, platelet-rich plasma (PRP) is the most exploited strategy. The aim of the present study was to systematically review the available literature to identify: 1) preclinical in-vivo results supporting the rational of PRP use for bone healing; 2) evidence from the clinical practice on the actual clinical benefit of PRP for the treatment of fractures and complications such as delayed unions and non-unions. METHODS: A systematic review of the literature was performed on the application of PRP in bone healing, using the following inclusion criteria: pre-clinical and clinical reports of any level of evidence, written in English language, published in the last 20 years (1996-2016), on the use of PRP to stimulate long-bone defect treatment, with focus on fracture and delayed/non-unions healing. RESULTS: The search in the Pubmed database identified 64 articles eligible for inclusion: 45 were preclinical in-vivo studies and 19 were clinical studies. Despite the fact that the overall pre-clinical results seem to support the benefit of PRP in 91.1 % of the studies, a more in depth analysis underlined a lower success rate, with a positive outcome of 84.4 % in terms of histological analysis, and even lower values considering radiological and biomechanical results (75.0 % and 72.7 % positive outcome respectively). This was also mirrored in the clinical literature, where the real benefit of PRP use to treat fractures and non-unions is still under debate. CONCLUSION: Overall, the available literature presents major limitations in terms of low quality and extreme heterogeneity, which hamper the possibility to optimize PRP treatment and translate it into a real clinical benefit despite positive preclinical findings on its biological potential to favour bone healing.

Intradiscal platelet-rich plasma (PRP) injections for discogenic low back pain: an update.

PURPOSE: The aim of this article is to provide an overview of clinical and translational research on intradiscal platelet-rich plasma (PRP) as a minimally invasive treatment for discogenic low back pain. METHODS: A literature review of in vitro, in vivo, and clinical studies was performed. RESULTS: There is strong in vitro evidence that supports the use of intradiscal PRP for discogenic low back pain. There are also promising findings in select preclinical animal studies. A clinical study of 29 participants who underwent intradiscal PRP injections for discogenic low back pain found statistically and clinically significant improvements in pain and function through two years of follow-up. CONCLUSIONS: Intradiscal PRP is a safe and a possibly effective treatment for discogenic low back pain. Future studies are warranted to determine the best candidates for this treatment, what the optimal injectate is and what relationships exist between patient-reported outcomes and radiological findings.