The efficacy of autologous platelet gel in pain control and blood loss in total knee arthroplasty. An analysis of the haemoglobin, narcotic requirement and range of motion. (1/196)

Biological materials used to assist in haemostasis following total knee arthroplasty have been the subject of much recent research. Autologous platelet gel is a substance that is derived from platelet-rich plasma extracted from the patient's blood and centrifuged perioperatively, and is applied to exposed tissues, synovium and the lining of the wound at closure. Concentrating and applying these factors directly to the wound at the end of a total knee arthroplasty procedure may lead to more complete haemostasis, a reduction in perioperative blood loss, accelerated tissue repair and decreased postoperative pain. In this study, 98 unilateral total knee arthroplasties were evaluated retrospectively, 61 of which involved the intaroperative use of platelet gel, and 37 of which served as control subjects. Outcomes analysed were postoperative haemoglobin changes, intravenous and oral narcotic requirements, range of motion on discharge and total days in hospital. Patients receiving platelet gel during surgery had less postoperative blood loss as measured by differences in the preoperative and postoperative haemoglobin on day 3 (2.7 vs. 3.2 g/dl; P=0.026). The narcotic requirement was less in the platelet gel group for both intravenous (17.0 vs. 36.3 mg/day; P=0.024) and oral (1.84 vs. 2.75 tabs/day; P=0.063) medication. This group also achieved a higher range of motion prior to discharge (78.2 vs. 71.9; P=0.052) and were discharged an average of 1 day earlier than their control counterparts. Though further prospective trials are necessary, this study indicates that the application of autologous platelet gel may lead to improved haemostasis, better pain control and a shortened hospital stay.  (+info)

Human AB serum and thrombin-activated platelet-rich plasma are suitable alternatives to fetal calf serum for the expansion of mesenchymal stem cells from adipose tissue. (2/196)

MSCs are currently in focus regarding their clinical potential in cell therapy and tissue engineering. However, most isolation and expansion protocols for clinical-scale production of MSCs use fetal calf serum (FCS) as a supplement, which poses a potential risk for infections as well as immunological reactions. To find a suitable FCS substitute, we investigated the effects of pooled human AB serum (AB-HS) and thrombin-activated platelet-rich plasma (tPRP) on adipose tissue MSCs (AT-MSCs) with FCS as the standard control medium. AT-MSCs of 10 donors were cultured under three different conditions: (a) 10% FCS, (b) 10% AB-HS, and (c) 10% tPRP. Colony-forming units, cumulative population doubling rates, and differentiation capacity toward the adipogenic and osteogenic lineages were assessed, along with immunophenotype. We demonstrated that AB-HS and tPRP provide a significantly higher proliferative effect on AT-MSCs than does FCS. In the first six passages, AB-HS and tPRP MSCs exhibited a fold expansion of 66.6 +/- 15.7 and 68.1 +/- 6.7, respectively, compared with 24.4 +/- 0.7 for FCS. Differentiation capacity was preserved throughout long-term culture. Immunophenotype was characteristic for MSCs and comparable for all culture conditions with the exception of a distinct CD45-/CD14-positive side population for AB-HS and tPRP that tended to diminish with prolonged culture. We showed that pooled human AB serum and thrombin-activated platelet-rich plasma are alternatives to FCS for AT-MSCs. These human sources are better characterized regarding potential infectious threats, while providing a higher proliferation rate and retaining differentiation capacity and mesenchymal stem cell marker expression throughout long-term culture. Disclosure of potential conflicts of interest is found at the end of this article.  (+info)

Bone grafting with platelet-rich plasma in alveolar cleft. Case report. (3/196)

Bone grafting of the alveolus has become an essential part of the contemporary surgical management of oral clefts. The benefits of this procedure are the stabilization of the maxillary arch, elimination of oronasal fistulae, the reconstruction of the soft tissue nasal base support, creation of bony support for subsequent tooth eruption or, when they are not present or not preserved, for implants application. The authors show a case of bone grafting with the aid of platelet-rich plasma (PRP). Because of the difficulties due to the oral cleft and to its surgical reparation (big size of bone defect, hard scars and sclerotic soft tissue) the authors decided to add PRP to a bone graft taken from the chin. PRP contains a high concentration of growth factors and is able to stimulate both wound and bone regeneration. Infact, the authors have observed very good results both in bone integration and in soft tissue reparation.  (+info)

Calcium sulfate and platelet-rich plasma make a novel osteoinductive biomaterial for bone regeneration. (4/196)

BACKGROUND: With the present study we introduce a novel and simple biomaterial able to induce regeneration of bone. We theorized that nourishing a bone defect with calcium and with a large amount of activated platelets may initiate a series of biological processes that culminate in bone regeneration. Thus, we engineered CS-Platelet, a biomaterial based on the combination of Calcium Sulfate and Platelet-Rich Plasma in which Calcium Sulfate also acts as an activator of the platelets, therefore avoiding the need to activate the platelets with an agonist. METHODS: First, we tested CS-Platelet in heterotopic (muscle) and orthotopic (bone) bone regeneration bioassays. We then utilized CS-Platelet in a variety of dental and craniofacial clinical cases, where regeneration of bone was needed. RESULTS: The heterotopic bioassay showed formation of bone within the muscular tissue at the site of the implantation of CS-Platelet. Results of a quantitative orthotopic bioassay based on the rat calvaria critical size defect showed that only CS-Platelet and recombinant human BMP2 were able to induce a significant regeneration of bone. A non-human primate orthotopic bioassay also showed that CS-Platelet is completely resorbable. In all human clinical cases where CS-Platelet was used, a complete bone repair was achieved. CONCLUSION: This study showed that CS-Platelet is a novel biomaterial able to induce formation of bone in heterotopic and orthotopic sites, in orthotopic critical size bone defects, and in various clinical situations. The discovery of CS-Platelet may represent a cost-effective breakthrough in bone regenerative therapy and an alternative or an adjuvant to the current treatments.  (+info)

Antibacterial effect of autologous platelet gel enriched with growth factors and other active substances: an in vitro study. (5/196)

Platelet-rich plasma is a new inductive therapy which is being increasingly used for the treatment of the complications of bone healing, such as infection and nonunion. The activator for platelet-rich plasma is a mixture of thrombin and calcium chloride which produces a platelet-rich gel. We analysed the antibacterial effect of platelet-rich gel in vitro by using the platelet-rich plasma samples of 20 volunteers. In vitro laboratory susceptibility to platelet-rich gel was determined by the Kirby-Bauer disc-diffusion method. Baseline antimicrobial activity was assessed by measuring the zones of inhibition on agar plates coated with selected bacterial strains. Zones of inhibition produced by platelet-rich gel ranged between 6 mm and 24 mm (mean 9.83 mm) in diameter. Platelet-rich gel inhibited the growth of Staphylococcus aureus and was also active against Escherichia coli. There was no activity against Klebsiella pneumoniae, Enterococcus faecalis, and Pseudomonas aeruginosa. Moreover, platelet-rich gel seemed to induce the in vitro growth of Ps. aeruginosa, suggesting that it may cause an exacerbation of infections with this organism. We believe that a combination of the inductive and antimicrobial properties of platelet-rich gel can improve the treatment of infected delayed healing and nonunion.  (+info)

Ultrastructural comparison of the morphology of three different platelet and fibrin fiber preparations. (6/196)

The aim of the current study was to investigate the ultrastructural morphology of three different sources of fibrin networks and platelets, namely, lyophilized human platelet-rich plasma (LPRP), freshly prepared human platelet-rich plasma (FPRP), and human platelet concentrate (HPC). The ultrastructural morphology of the three different fibrin networks was studied using the scanning electron microscope (SEM). Turbidity curves were drawn at 405 nm at room temperature and fibrinogen concentrations were measured. Scanning electron micrographs showed that all clots produced thick major fibrin fibers as well as a well-defined fine fibrin network, which appeared to be a superimposed process that occurred after the major fibrin network was established. These features were decidedly more pronounced in the HPC specimens. Turbidity curves of the three types of plasma showed differences in LPRP and FPRP. Fibrinogen concentrations of all three preparations were in the normal ranges. Because of the great similarity between LPRP, HPC, and FPRP, we suggest that LPRP could be used successfully to study morphological changes in fibrin fibers and platelets, which may occur after exposure to certain therapeutic agents. However, functionality studies such as turbidity curves should concurrently be included. We therefore conclude that from a basic science point of view, LPRP is a valuable research tool and that such results may add information that could be valuable for clinical application.  (+info)

Platelet aggregation studies: autologous platelet-poor plasma inhibits platelet aggregation when added to platelet-rich plasma to normalize platelet count. (7/196)

Adjusting platelet count (PC) in platelet-rich plasma (PRP) using platelet-poor plasma (PPP) is recommended for platelet aggregation (PA) studies, but it could also affect PA independently of the decrease in PC. Analysis of aggregation tracings from healthy controls showed that PC correlated with PA in 47 diluted-PRPs, but not in 104 undiluted-PRPs. Dilution of 9 PRPs with PPP progressively decreased PA, while dilution of washed platelets with buffer hardly affected PA. Apyrase partially prevented the inhibitory effect of PPP. Therefore, the practice of diluting PRP with PPP to adjust platelet count should be avoided because it artefactually inhibits PA.  (+info)

Enzymes and receptors of prostaglandin pathways with arachidonic acid-derived versus eicosapentaenoic acid-derived substrates and products. (8/196)

Dietary fish oil containing omega 3 highly unsaturated fatty acids has cardioprotective and anti-inflammatory effects. Prostaglandins (PGs) and thromboxanes are produced in vivo both from the omega 6 fatty acid arachidonic acid (AA) and the omega 3 fatty acid eicosapentaenoic acid (EPA). Certain beneficial effects of fish oil may result from altered PG metabolism resulting from increases in the EPA/AA ratios of precursor phospholipids. Here we report in vitro specificities of prostanoid enzymes and receptors toward EPA-derived, 3-series versus AA-derived, 2-series prostanoid substrates and products. The largest difference was seen with PG endoperoxide H synthase (PGHS)-1. Under optimal conditions purified PGHS-1 oxygenates EPA with only 10% of the efficiency of AA, and EPA significantly inhibits AA oxygenation by PGHS-1. Two- to 3-fold higher activities or potencies with 2-series versus 3-series compounds were observed with PGHS-2, PGD synthases, microsomal PGE synthase-1 and EP1, EP2, EP3, and FP receptors. Our most surprising observation was that AA oxygenation by PGHS-2 is only modestly inhibited by EPA (i.e. PGHS-2 exhibits a marked preference for AA when EPA and AA are tested together). Also unexpectedly, TxA(3) is about equipotent to TxA(2) at the TP alpha receptor. Our biochemical data predict that increasing phospholipid EPA/AA ratios in cells would dampen prostanoid signaling with the largest effects being on PGHS-1 pathways involving PGD, PGE, and PGF. Production of 2-series prostanoids from AA by PGHS-2 would be expected to decrease in proportion to the compensatory decrease in the AA content of phospholipids that would result from increased incorporation of omega 3 fatty acids such as EPA.  (+info)