Re: "The effects of local platelet rich plasma delivery on diabetic fracture healing". What do we use: Platelet-rich plasma or platelet-rich gel?

Application of autologous platelet-rich gel formed by calcium gluconate combined with hormone therapy for endometrial repair after hysteroscopic transcervical resection of adhesion surgery and successful pregnancy: case report and literature review

Introduction

Intrauterine adhesion (IUA), a common gynecological disease, is mainly caused by traumatic or infectious factors that lead to basal endometrial layer physiological repair disorders. IUA is mostly treated via hysteroscopic transcervical resection of adhesion and although it can restore uterine cavity shape, its endometrial repair effectiveness is limited. The figures showed that after surgery, patients with IUA have a high recurrence rate. Therefore, quick endometrial damage repair is key to successful treatment.

Case presentation

A 34-year-old patient visited our hospital after experiencing amenorrhea for 4 months following an induced abortion and had a fertility requirement. Based on the American Fertility Society intrauterine scores, the patient was diagnosed with moderate IUA. She underwent transcervical resection of adhesion, followed by autologous platelet-rich gel intrauterine perfusion and periodic estrogen-progesterone treatment for three menstrual cycles. No complications developed during treatment and the patient's endometrium was significantly repaired, with successful pregnancy being achieved.

Conclusion

Autologous platelet-rich gel promoted endometrial repair and acted as a mechanical barrier to prevent intrauterine adhesion. This approach May offer new insights into IUA treatment.

Evolution, current status and advances in application of platelet concentrate in periodontics and implantology

Platelet concentrates (PC) [platelet-rich plasma (PRP) and platelet-rich fibrin (PRF)] are frequently used for surgical procedures in medical and dental fields, particularly in oral and maxillofacial surgery, plastic surgery and sports medicine. The objective of all these technologies is to extract all the elements from a blood sample that could be used to improve healing and promote tissue regeneration. Although leukocyte rich and leukocyte poor PRP's have their own place in literature, the importance of non-platelet components in a platelet concentrate remains a mystery. PC have come a long way since its first appearance in 1954 to the T-PRF, A-PRF and i-PRF introduced recently. These PC find varied applications successfully in periodontics and implant dentistry as well. However, the technique of preparation, standing time, transfer process, temperature of centrifuge, vibration, etc., are the various factors for the mixed results reported in the literature. Until the introduction of a proper classification of terminologies, the PC were known by different names in different countries and by different commercial companies which also created a lot of confusion. This review intends to clarify all these confusion by briefing the exact evolution of PC, their preparation techniques, recent advances and their various clinical and technical aspects and applications.

A Comparative Study: Taxonomic Grouping of Alkaline Protease Producing Bacilli

Alkaline proteases have biotechnological importance due to their activity and stability at alkaline pH. 56 bacteria, capable of growing under alkaline conditions were isolated and their alkaline protease activities were carried out at different parameters to determine their optimum alkaline protease production conditions. Seven isolates were showed higher alkaline protease production capacity than the reference strains. The highest alkaline protease producing isolates (103125 U/g), E114 and C265, were identified as Bacillus licheniformis with 99.4% and Bacillus mojavensis 99.8% based on 16S rRNA gene sequence similarities, respectively. Interestingly, the isolates identified as Bacillus safensis were also found to be high alkaline protease producing strains. Genotypic characterizations of the isolates were also determined by using a wide range of molecular techniques (ARDRA, ITS-PCR, (GTG)5-PCR, BOX-PCR). These different techniques allowed us to differentiate the alkaliphilic isolates and the results were in concurrence with phylogenetic analyses of the 16S rRNA genes. While ITS-PCR provided the highest correlation with 16S rRNA groups, (GTG)5-PCR showed the highest differentiation at species and intra-species level. In this study, each of the biotechnologically valuable alkaline protease producing isolates was grouped into their taxonomic positions with multi-genotypic analyses.

Role of autologous platelet-rich plasma in treatment of long-bone nonunions: a prospective study

PURPOSE

Fracture union is a complex biological process, which depends upon several systemic and local factors. Disturbance of any of these factors may lead to nonunion of the fracture. These nonunions have a huge impact on quality of life as well as socioeconomical aspects. The platelets on activation release a number of growth factors and differentiation factors, which play important role in fracture healing. This study aimed to look for efficacy of platelet-rich plasma in the treatment of established fracture nonunions of long bones.

METHODS

A total of 94 patients with established nonunion of long bone (35 tibia, 30 femur, 11 humerus, 4 radius, 12 ulna, 2 with both radius and ulna) were included in this study. We injected 15-20 ml of autologous platelet-rich plasma (>2,000,000 platelets/μl) under image intensifier at each nonunion site. The fracture union was evaluated clinically and radiologically regularly at monthly interval till 4 months.

RESULTS

Eighty-two patients had their fracture united at the end of 4 months. Thirty-four patients showed bridging trabeculae on X-rays at the end of 2 months, while 41 patients showed bridging trabeculae at the end of third month. Twelve patients did not show any attempt of union at 4 months and were labeled as failure of treatment. There were no complications.

CONCLUSION

Platelet-rich plasma is a safe and effective treatment for the treatment of nonunions. More studies are needed to look into molecular mechanism of this fracture healing acceleration by platelet-rich plasma.

Platelet-Rich Preparations to Improve Healing. Part I: Workable Options for Every Size Practice

Numerous studies have demonstrated that platelet-rich preparations applied to surgical sites, injuries, or wounds are a safe and effective way to promote soft tissue healing and bone growth. Various protocols have been developed for preparing platelet-rich preparations, with subtle but important differences between them. Unfortunately, only a minority of clinicians use platelet-rich preparations, such as platelet-rich plasma and platelet-rich fibrin, in their practice, possibly due to confusion about the different methods and their advantages and disadvantages. Therefore, the different types of preparations are described to help guide the selection of the best method for any size practice. Classic methods generally require large volumes of blood and can be expensive, complicated, and time-intensive. Simpler protocols have been developed recently, which require relatively inexpensive equipment and small blood volumes and, thus, may be more applicable for small clinical practices. Platelet-rich preparations accelerate healing at earlier time points to reduce discomfort and the potential for adverse outcomes, including infection, poor wound closure, and delays in forming strong bone for subsequent procedures (such as implants). However, platelet-rich preparations may also improve long-term outcomes in patients expected to have impaired healing, such as with lifestyle choices (eg, smoking), medications (eg, steroids), diseases (eg, diabetes, osteoporosis, atherosclerosis), and aging, by supplementing the deficient wound environment to restore proper healing. Therefore, both large and small clinical practices would benefit from utilizing platelet-rich preparations to enhance healing in their patients.

Efficacy of leukocyte- and platelet-rich plasma gel (L-PRP gel) in treating osteomyelitis in a rabbit model

Leukocyte- and platelet-rich plasma gel (L-PRP gel), a new autologous product which was previously utilized in several surgical procedures to enhance tissue healing, is now increasingly used as a promising treatment method for infections. In this study, we investigated the antibacterial property of L-PRP gel against Methicillin-resistive Staphylococcus aureus (MRSA, ATCC 43300) in a rabbit model of osteomyelitis. Tibial osteomyelitis was induced in 40 New Zealand white rabbits using the MRSA strain. Three weeks after induction, the rabbits with tibial osteomyelitis were randomly divided into four groups: Control group (no treatment); Van group (debridement and parenteral treatment with vancomycin alone); L-PRP gel + Van group (debridement and local L-PRP gel injection, plus parenteral treatment with vancomycin); L-PRP gel group (debridement and local L-PRP gel injection). All rabbits were sacrificed 6 weeks after debridement. The antibacterial efficacy was evaluated by radiological, microbiological, and histological examinations. Newly formed bone was also quantified. The best therapeutic efficacy, including infection elimination and bone defect repair, was observed in the L-PRP gel + Van group. Although not comparable to vancomycin, L-PRP gel also exibited antimicrobial efficacy in vivo. We believe that a combination of L-PRP gel and antibiotics could be a favorable alternative for the treatment of osteomyelitis.

THE USE OF PLATELET RICH PLASMA WITH BONE MARROW ASPIRATE IN PUDDU TIBIAL OSTEOTOMY

Objective: The present study was performed in order to evaluate the use of platelet rich plasma associated to bone marrow aspirate, substituting autologous iliac bone graft in medial opening wedge osteotomy (OWHTO). Methods: Twenty-five patients were submitted to tibial opening wedge osteotomy, being divided into two groups. Iliac group: 14 patients submitted to OWHTO, using autologous iliac bone graft to fill the gap. PRP group: 11 patients using platelet rich plasma associated to bone marrow aspirate to fill the gap. We evaluated bleeding (hemoglobin and hematocrit levels) and pain (visual analogic scale-VAS), then we compared the groups regarding these variables. Results: Differences between the groups were not found regarding hemoglobin levels (p=0.820) and hematocrit levels (p=0.323). The groups were not different regarding pain measured with VAS (p=0.538). Conclusion: The use of platelet rich plasma associated to bone marrow aspirate in medial opening wedge osteotomy did not offer advantages over autologous iliac bone graft regarding bleeding and pain.

Benefit of percutaneous injection of autologous platelet-leukocyte-rich gel in patients with delayed union and nonunion

This article reports the efficacy of percutaneous autologous platelet-leukocyte-rich gel (PLRG) injection as a minimally invasive method alternative to open grafting techniques. Each of 32 participants was followed on a regular basis with clinical examinations, roentgenograms, dual-energy X-ray absorptiometry examinations. In the delayed union group, the average time to union was 9.3 weeks after PLRG injection and the union was achieved in all cases. In the nonunion group, the union was observed in 13 of 20 cases and the average time to union was 10.3 weeks after PLRG injection. Interestingly, in patients in whom union was not achieved, the average time from the fracture and/or from the last operation was >11 months. This is our initial experience with the use of PLRG as biologic treatment for delayed union or nonunion. Our investigation showed that percutaneous PLRG injection in delayed union is a sufficient method to obtain union, which is less invasive procedure than bone marrow injection. Percutaneous PLRG grafting can be also an effective method for the treatment of selected cases of nonunion. The essential factor is the average time from the initial surgery to PLRG injection for nonunion; <11 months seems to be critical for good outcomes.

Reviewing the Structural Features of Autologous Platelet-Leukocyte Gel and Suggestions for Use in Surgery

The therapeutic use of autologously prepared platelet-leukocyte gel (PLG) is a relatively new technology which might stimulate and accelerate soft-tissue and bone healing. The effectiveness of this procedure lies in the exogenous delivery of a wide range of platelet growth factors, intentionally released from autologously prepared PLG. The rationale to employ this technique is to mimic physiological wound healing and reparative tissue processes. Despite an increase in clinical PLG applications, the structures and kinetics of this biological material have not been completely examined. Electron microscopic imaging was performed to evaluate platelet-leukocyte gel structures. Furthermore, directions for PLG application are presented, based on results from published articles in various surgical disciplines. In conclusion, PLG can be useful in a wide range of clinical applications to enhance healing following surgical procedures, since exogenous applied PLG releases instantly platelet growth factors, in the presence of leukocytic cells.

Antibacterial effect of autologous platelet gel enriched with growth factors and other active substances

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.