Relationship between mindfulness, stress, and performance in medical students in pediatric emergency simulations.

Objectives: Pediatric teams of emergency departments work under extreme stress, which affects high-level cognitive functions, specifically attention and memory. Therefore, the methods of stress management are being sought. Mindfulness as a process of intentionally paying attention to each moment with acceptance of each experience without judgment can potentially contribute to improving the performance of medical teams. Medical simulation is a technique that creates a situation to allow persons to experience a representation of a real event for the purpose of education. It has been shown that emergency medicine simulation may create a high physiological fidelity environment similarly to what is observed in a real emergency room. The aim of our study was to determine whether the technical and non-technical skills of medical students in the course of pediatric high fidelity simulations are related to their mindfulness and stress. Participants and methods: A total of 166 standardized simulations were conducted among students of medicine in three simulation centers of medical universities, assessing: stress sensation (subjectively and heart rate/blood pressure), technical (checklists) and non-technical skills (Ottawa scale) and mindfulness (five facet mindfulness questionnaire): ClinicalTrials.gov ID: NCT03761355. Results: The perception of stress among students was lower and more motivating if they were more mindful. Mindfulness of students correlated positively with avoiding fixation error. In the consecutive simulations the leaders' non-technical skills improved, although no change was noted in their technical skills. Conclusion: The results of our research indicate that mindfulness influence the non-technical skills and the perception of stress of medical students during pediatric emergency simulations. Further research is needed to show whether mindfulness training leads to improvement in this field.

Multidrug-Resistant Micro-Organisms Associated with Urinary Tract Infections in Orthopedic Patients: A Retrospective Laboratory-Based Study.

BACKGROUND: The risk of healthcare-associated infections (HAIs) in surgical wards remains closely related to the type of surgery and procedures performed on patients. Those factors also condition the risk of various forms of clinical infections, especially urinary tract infections (UTIs). UTIs are most frequently (70-80% of cases) caused by the use of bladder catheter in the perioperative period. The aim of this study was to perform an epidemiological and microbiological analysis of UTIs in orthopedic patients, with an emphasis on multidrug-resistant (MDR) micro-organisms. Methods: The study was conducted in a 38-bed Department of Orthopedic-Traumatic Surgery in Sosnowiec, Poland. 5239 patients, operated on in 2013-2015, were included in the study. The urinary catheter use rate was 30.7%. Laboratory-based study used the UTI definition of the HAI-Net program. A micro-organism was declared MDR if it was resistant to at least one antibiotic from three or more groups of antibacterial drugs, and extensively drug-resistant (XDR) if it was sensitive to antibiotics from no more than two groups of drugs. Results: The UTI incidence was 3.2% (168 cases), the CA-UTI incidence density was 9.6/1000 catheter days. The highest risk of UTI was found in patients aged 75 or older. Monomicrobial cultures were detected in 163 specimens (78% of all microbiologically confirmed UTIs). Gram-negative flora prevailed among the micro-organisms, the predominantly isolated Enterobacteriaceae being Escherichia coli and Klebsiella pneumoniae. In 16 patients (7.7% of microbiologically confirmed UTIs), yeast infection was confirmed. Isolated micro-organisms were fully sensitive to carbapenems. Gram-negative bacilli showed the lowest sensitivity to extended substrate spectrum penicillins and fluoroquinolones (37-64%), as well as to trimethoprim-sulfamethoxazole (50%). The MDR prevalence was 24.4%. Conclusions The presented data indicates that UTIs are a significant problem in the studied population, so is antimicrobial resistance, especially to quinolones, and extended-spectrum cephalosporins, which are often used as first-line therapy. To tackle the problem of high UTI incidence and MDR prevalence, reducing the UTI risk factors should be prioritized.

Potential Effect of SOX2 on the Cell Cycle of Wharton's Jelly Stem Cells (WJSCs).

The connective tissue of the umbilical cord contains stem cells called Wharton's jelly cells. These cells express core transcription factors (NANOG, OCT4, and SOX2). The protein product of the SOX2 gene controls the cell cycle by interacting with cyclin D (directly and indirectly) and cycle inhibitors-p21 and p27, as well as two E2f3 protein isoforms. The aim of the study was to analyze the effect of SOX2 on the cell cycle of stem cells of Wharton's jelly. The material for the study was the stem cells of Wharton's jelly isolated from 20 umbilical cords collected during childbirth. The stem cells collected were subjected to cytometric analysis, cell culture, and RNA isolation. cDNA was the starting material for the analysis of gene expression: SOX2, CCND1, CDK4, and CDKN1B. The studies indicate a high proliferative potential of the Wharton's jelly stem cells and the inhibitory effect of SOX2 on the expression of the CCND1 and CDK4 gene.

Allergic reaction to platelet-rich plasma (PRP): Case report.

RATIONALE: In the recent years, growing interest is focused on the use of platelet-rich plasma (PRP) in wound healing and tissue regeneration. There are a number of papers regarding the usefulness of PRP in the healing of ulcerations, skin injures, bone loss or distraction osteogenesis. Most authors emphasize the safety of PRP usage due to its authogenic nature. PATIENT CONCERNS: We present a case of a 14 -year-old boy admitted to our department due to simple bone cyst of the distal tibia, qualified for injection of PRP into the cyst. PRP was separated with the use of Magellan Autologous Platelet Separator System (Arteriocyte Medical Systems Hopkington, MA) according to the manufacturers' manual. Immediately after separation during short-term IV anaesthesia, 3 mL of PRP was installed to the bone cyst under image intensifier control. DIAGNOSES: Within the first 24 hours after exposure to PRP, the skin rash appeared. Physical examination revealed the small red papular, regionally purpuric eruptions, mainly concentrated on the upper extremities and on more warmed regions of skin, in association with pharyngitis, tonsillar enlargement, mucopurulent discharge in the posterior pharynx and swelling of the eyelids. INTERVENTIONS: As the patient received calcium citrate with the PRP injection additional calcium citrate test were performed. Skin prick testing (negative) was and an intradermal test was positive (10×13 mm). Treatment included Claritine (Loratidinum) and Clemastin (Clemastinum)-both antihistaminic drugs. OUTCOMES: All symptoms withdrew and the patient was released home after 4 days. The patient is in 6 years follow-up without any symptoms of allergic disease. LESSONS: Our case shows that safety of use of PRP is not absolutely sure. The pure autologous tissue is safe, but preparation for its use can substantially decrease this safety. In our patient, only limited skin reaction to calcium citrate was observed, but general reaction leading to anaphylactic shock cannot be excluded. In order to reduce the risk of side effects skin test should be performed but as there were no records of allergic diseases on family and patients medical history this should apply to all patients.

Can surgical site infections be controlled through microbiological surveillance? A three-year laboratory-based surveillance at an orthopaedic unit, retrospective observatory study.

OBJECTIVE: The aims of the study were to analyse the surgical site infections (SSIs) in patients operated at an orthopaedic ward and to describe the drug-resistance of the aetiology of those infections. Also, analyse the possibility of SSI control through microbiological surveillance. Additionally, we have studied the information inferred by aggregating cumulative antibiograms for the SSIs of the studied orthopaedic unit. DESIGN: Cross-sectional studies carried out in 2013-2015. SETTING AND PATIENTS: Orthopaedic and Trauma Surgery Unit in Sosnowiec, Poland; 5995 patients, 5239 operations. METHODS: Retrospective laboratory-based data collection study of surgical site infections. RESULTS: SSI incidence rate was 6.6%, in the implantations-hip prosthesis 5.8% and knee prosthesis 5.4%, about 6 times higher compared with European HAI-Net. SSIs were usually caused by Gram-positive bacteria (56%). The prevalence of MDR microorganisms was 22.6%, and mainly concerned the Gram-negative bacilli: 97.6% of Acinetobacter baumannii and 50.0% of Klebsiella pneumoniae were multidrug-resistant. On the basis of what the Formula for Rational Empiric Antimicrobial Therapy analysis has shown, the use of amikacin, imipenem and ciprofloxacin has been recommended as the most efficient in the empirical therapy of SSIs. CONCLUSIONS: The infection control was a significant problem at the studied orthopaedic unit, as evidenced by the SSI incidence rate significantly higher than expected. We suggest implementing the infection control and prevention based on evidence-based medicine, and a unit-based surveillance. A cumulative unit-based antibiogram reflects the drug-susceptibility pattern for the strains from the infections acquired at the unit.

A new aspect of in vitro antimicrobial leukocyte- and platelet-rich plasma activity based on flow cytometry assessment.

The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby-Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity.

High-Fidelity Hybrid Simulation: A Novel Approach to Teaching Pediatric and Adolescent Gynecology.

STUDY OBJECTIVE: To describe a hybrid simulation model for pediatric and adolescent gynecology (PAG) examination teaching, to evaluate if it would be feasible to be conducted as a part of the PAG training, and to find out how it would be perceived by the trainees. DESIGN: The development process and a 2-day workshop is presented. SETTING: An academic 2-day PAG simulation training at the Medical University of Lublin Centre of Medical Simulation. PARTICIPANTS: Twenty-two obstetrics and gynecology and pediatric residents from various hospitals of the Lublin county region. INTERVENTIONS: Participants took part in a 2-day simulation-based workshop consisting of a theoretical part and 3 high-fidelity PAG simulation scenarios, followed by an anonymous feedback survey on their opinions about the hybrid model teaching strategy. MAIN OUTCOME MEASURES: To describe and evaluate feasibility of a hybrid simulation model for PAG examination teaching and to report students' satisfaction and acceptance of this teaching modality; to share faculty experience and lessons learned during the development process. RESULTS: Of 22 initially enrolled residents, 16 of them completed the simulation-based session. All but 1 participant preferred a hybrid model to a task trainer as a teaching modality. The same number of surveyed residents stated that they learned more using the hybrid model. Qualitative feedback from the participants was overall positive. CONCLUSION: A hybrid model for teaching PAG examination is feasible and greatly accepted by the trainees. We are convinced that such a model of training can improve trainees' skills and translate to PAG patients' comfort and safety. It could be potentially used in teaching more difficult procedures (eg, intrauterine device insertion or examination after sexual assault).

A review of decellurization methods caused by an urgent need for quality control of cell-free extracellular matrix' scaffolds and their role in regenerative medicine.

The natural extracellular matrix (ECM),thanks to its specific properties (e.g., collagenous lattice, a reservoir of growth factors, ECM-cell anchoring areas, an optimal pH and CO2 ),ensures an optimal microenvironment for homeostatic and regenerative cell development. In the context of regenerative medicine, ECM is a lair for residual and infiltrative cells. The aim of the clinical usage of cell-free ECM scaffolds is the enhancement of tissue regeneration with possible minimization of an adverse host reaction on allogeneic or xenogeneic biomaterial. Thus, the objective of decellularization is to obtain acellular grafts characterized by optimal biological properties, such as a lack of remaining cellular elements (e.g., cell membrane phospholipids and proteins, nucleic acids, mitochondria), lack of immunogenicity, lack of calcification promotion and lack of cytotoxicity (e.g., in unrinsed detergents). Furthermore, cell-free ECM scaffolds should present the optimal mechanical and structural properties that may ensure the biocompatibility of the graft. The maintenance of the ultrastructure composition of the ECM is one of the most important goals of decellularization. All physical, chemical, and biological methods proposed (used separately or in combination to extract cells from tissues/organs) are not 100% effective in cell removal and always cause a disruption of the ECM texture, as well as a probable loss of important structure components. Although cell-free ECM scaffolds are generally classified as medical devices, there are no widely accepted or legally defined criteria for quality control/evaluation methods of obtained matrices. Such criteria must be provided. Some of them have been proposed in this manuscript. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 909-923, 2018.

Dermatan sulfate is a player in the transglutaminase 2 interaction network.

Transglutaminase 2 (TG2) is a multifunctional protein that is primarily engaged in cell adhesion/signaling or shows Ca2+-dependent transglutaminase activity in the extracellular space of tissues. This latter action leads to the cross-linking of the extracellular matrix (ECM) proteins. The enhanced extracellular expression of TG2 is associated with processes such as wound healing, fibrosis or vascular remodeling that are also characterized by a high deposition of dermatan sulfate (DS) proteoglycans in the ECM. However, it is unknown whether DS may bind to TG2 or affect its function. Using the plasmon surface resonance method, we showed that DS chains, especially those of biglycan, are good binding partners for TG2. The interaction has some requirements as to the DS structure. The competitive effect of heparin on DS binding to TG2 suggests that both glycosaminoglycans occupy the same binding site(s) on the protein molecule. An occurrence of the DS-TG2 interaction was confirmed by the co-immunoprecipitation of this protein with native decorin that is a DS-bearing proteoglycan rather than with the decorin core protein. Moreover, in vivo DS is responsible for both TG2 binding and the regulation of the location of this protein in the ECM as can be suggested from an increased extraction of TG2 from the human fascia only when an enzymatic degradation of the tissue DS was conducted in the presence of the anti-collagen type I antiserum. In addition, DS with a low affinity for TG2 exerted an inhibitory effect on the protein transamidating activity most probably via the control of the accessibility of a substrate. Our data show that DS can affect several aspects of TG2 biology in both physiological and pathological conditions.

Benefit of Leukocyte- and Platelet-Rich Plasma in Operative Wound Closure in Oral and Maxillofacial Surgery.

This article reports the influence of an autologous leukocyte- and platelet-rich plasma (L-PRP) injection as a minimally invasive method on supporting wound healing processes after a mandibular odontogenic cystectomy and double mandibular fracture fixation. 113 patients were enrolled into a control group (received no L-PRP injection) and 102 patients were enrolled into an L-PRP group with an oral mucosa incision. 18 patients after a double mandibular fracture were operated on using 2 external submandibular approaches receiving no fluids in the right site (a control group) and an L-PRP injection in the left incision (L-PRP group). Clinical observations showed that the oral mucosa healed faster in patients treated with L-PRP, in comparison to cases where inductive biomaterial was not added. Pain at the L-PRP injection site was relieved within few hours after an operation in patients with double mandibular fractures. However, there were no differences observed in the progression of the healing process. L-PRP possesses inductive properties that could stimulate healing processes and it seems to be one of the most promising methods in the future for the treatment of soft tissue defects.

Classification of platelet concentrates (Platelet-Rich Plasma-PRP, Platelet-Rich Fibrin-PRF) for topical and infiltrative use in orthopedic and sports medicine: current consensus, clinical implications and perspectives.

Platelet concentrates for topical and infiltrative use - commonly termed Platetet-Rich Plasma (PRP) or Platelet-Rich Fibrin (PRF) - are used or tested as surgical adjuvants or regenerative medicine preparations in most medical fields, particularly in sports medicine and orthopaedic surgery. Even if these products offer interesting therapeutic perspectives, their clinical relevance is largely debated, as the literature on the topic is often confused and contradictory. The long history of these products was always associated with confusions, mostly related to the lack of consensual terminology, characterization and classification of the many products that were tested in the last 40 years. The current consensus is based on a simple classification system dividing the many products in 4 main families, based on their fibrin architecture and cell content: Pure Platelet-Rich Plasma (P-PRP), such as the PRGF-Endoret technique; Leukocyte- and Platelet-Rich Plasma (LPRP), such as Biomet GPS system; Pure Platelet-Rich Fibrin (P-PRF), such as Fibrinet; Leukocyte- and Platelet-Rich Fibrin (L-PRF), such as Intra-Spin L-PRF. The 4 main families of products present different biological signatures and mechanisms, and obvious differences for clinical applications. This classification serves as a basis for further investigations of the effects of these products. Perspectives of evolutions of this classification and terminology are also discussed, particularly concerning the impact of the cell content, preservation and activation on these products in sports medicine and orthopaedics.

Arthroplasty in patients with congenital hip dysplasia--early evaluation of a treatment method.

BACKGROUND: Developmental hip dysplasia (DHD) is the most common cause of secondary hip osteoarthritis (OA). It often leads to OA in young, active and working adults. The aim of our study is to evaluate the results of THA in patients with DHD. MATERIAL AND METHODS: Total hip arthroplasty was performed in 15 patients with DHD - 13 women (average age - 39) and 2 men (average age - 44) between June 2010 to June 2011. Patient's hips were estimated by Crowe classification to evaluate the severity of degenerative arthritis. Patients we reassessed with Harris Hip Score before and after the surgery. RESULTS: The mean preoperative score was 44.6 points, directly after surgery 62.4 pts., 6 months after 78.6 points. After artrhroplasty, improvement was noted in walking stairs without railing, walking without support, sitting on chair for more than 1 hour. Before the surgery average difference in limbs" length was 4 cm After the treatment it was reduced to 0.5 cm. Mean hip flexion was 40 ° before, 90 ° after the surgery, mean abduction was respectively 0° and 25°. Our study proves that total hip arthroplasty in patients with developmental dysplasia of hip helps to improve stability and mobility of joint and to reduce the pain. CONCLUSIONS: 1. In the type 1 and 2 according to Crow's classification, good clinical results may be achieved using standard prosthesis stem sizes and press-fit acebutalar component with possibly the smallest diameter providing stable placing. 2. In the case of ty pe III good results are observed using acetabular press-fit method for fixing, after reconstruction of bone defects with osteogenous bone graft. 3. The usage of big head dimensions gives beneficial effects on the osseointegration of the acetabular component and reduces the risk of dislocation. 4. A short follow-up period of the group of patients presented requires further prospective study to evaluate the long-term results.

Abduction dislocation of the knee joint--a case study.

The paper presents a case of untypical, not included in existing classifications, knee joint dislocation in a young man. An MRI scan confirmed a rupture of both cruciate ligaments and damage to the ligamento-capsular complex on the medial side of the knee joint. Two weeks after injury, an arthroscopy was performed with joint lavage followed by repair of the damaged ligamento-capsular complex. A very good functional result was obtained three years after the injury, in spite of the patient not having consented to an elective cruciate ligament reconstruction.

A side-effect induced by the combination of a demineralized freeze-dried bone allograft and leucocyte and platelet-rich plasma during treatment for large bone cysts: a 4-year follow-up clinical study.

During platelet activation over 30 growth factors are released from their alpha granules. By concentrating platelets, higher levels of growth factors are obtained and can be used to stimulate the healing processes. Moreover, during blood centrifugation, huge numbers of leukocytes and thrombocytes can be obtained to form leukocyte and platelet-rich plasma (L-PRP). After platelet degranulation the active gelatinous matrix called leukocyte and platelet-rich gel (L-PRG) is formed. In the present clinical study, we report the influence of PLRG and freeze-dried allografts on healing of large femoral bone cysts. Each of 6 participants was followed on a regular basis with clinical examinations, roentgenograms and dual-energy X-ray absorptiometry (DXA) examinations. Our four-year follow up clinical study using allografts and PLRG in the treatment of large cystic lesions of the proximal femur showed that mixing these substances is not efficient and it might induce unknown local reactions between them causing complete bone graft destruction. Further studies are necessary to fully understand the mechanisms of the local activity of L-PRP gel.

Locked intramedullary nailing in the treatment of non-union following humeral shaft fractures. Cases study.

The paper presents an analysis of cases of treatment of humeral shaft fracture non-union following operative treatment. Non-union was treated by locked intramedullary nailing in all patients. Bone destruction at the fracture site is an indication for using bone grafts. In our opinion autologous bone marrow injection to the fracture site is an effective method of bone union stimulation, and this non-invasive procedure may be repeated several times. Stable osteosynthesis promotes callus formation and remodeling, and enables early rehabilitation.

The role of leukocytes from L-PRP/L-PRF in wound healing and immune defense: new perspectives.

Platelet concentrates for topical use are innovative tools of regenerative medicine and their effects in various therapeutical situations are hotly debated. Unfortunately, this field of research mainly focused on the platelet growth factors, and the fibrin architecture and the leukocyte content of these products are too often neglected. In the four families of platelet concentrates, 2 families contain significant concentrations of leukocytes: L-PRP (Leukocyte- and Platelet-Rich Plasma) and L-PRF (Leukocyte- and Platelet-Rich Fibrin). The presence of leukocytes has a great impact on the biology of these products, not only because of their immune and antibacterial properties, but also because they are turntables of the wound healing process and the local factor regulation. In this article, the various kinds of leukocytes present in a platelet concentrate are described (particularly the various populations of granulocytes and lymphocytes), and we insist on the large diversity of factors and pathways that these cells can use to defend the wound site against infections and to regulate the healing process. Finally, the impact of these cells in the healing properties of the L-PRP and L-PRF is also discussed: if antimicrobial properties were already pointed out, effects in the regulation of cell proliferation and differentiation were also hypothesized. Leukocytes are key actors of many platelet concentrates, and a better understanding of their effects is an important issue for the development of these technologies.

Do the fibrin architecture and leukocyte content influence the growth factor release of platelet concentrates? An evidence-based answer comparing a pure platelet-rich plasma (P-PRP) gel and a leukocyte- and platelet-rich fibrin (L-PRF).

Platelet concentrates for surgical use are tools of regenerative medicine designed for the local release of platelet growth factors into a surgical or wounded site, in order to stimulate tissue healing or regeneration. Leukocyte content and fibrin architecture are 2 key characteristics of all platelet concentrates and allow to classify these technologies in 4 families, but very little is known about the impact of these 2 parameters on the intrinsic biology of these products. In this demonstration, we highlight some outstanding differences in the growth factor and matrix protein release between 2 families of platelet concentrate: Pure Platelet-Rich Plasma (P-PRP, here the Anitua's PRGF - Preparation Rich in Growth Factors - technique) and Leukocyte- and Platelet-Rich Fibrin (L-PRF, here the Choukroun's method). These 2 families are the extreme opposites in terms of fibrin architecture and leukocyte content. The slow release of 3 key growth factors (Transforming Growth Factor ß1 (TGFß1), Platelet-Derived Growth Factor AB (PDGF-AB) and Vascular Endothelial Growth Factor (VEGF)) and matrix proteins (fibronectin, vitronectin and thrombospondin-1) from the L-PRF and P-PRP gel membranes in culture medium is described and discussed. During 7 days, the L-PRF membranes slowly release significantly larger amounts of all these molecules than the P-PRP gel membranes, and the 2 products display different release patterns. In both platelet concentrates, vitronectin is the sole molecule to be released almost completely after only 4 hours, suggesting that this molecule is not trapped in the fibrin matrix and not produced by the leukocytes. Moreover the P-PRP gel membranes completely dissolve in the culture medium after less than 5 days only, while the L-PRF membranes are still intact after 7 days. This simple demonstration shows that the polymerization and final architecture of the fibrin matrix considerably influence the strength and the growth factor trapping/release potential of the membrane. It also suggests that the leukocyte populations have a strong influence on the release of some growth factors, particularly TGFß1. Finally, the various platelet concentrates present very different biological characteristics, and an accurate definition and characterization of the different families of product is a key issue for a better understanding and comparison of the reported clinical effects of these surgical adjuvants.

In search of a consensus terminology in the field of platelet concentrates for surgical use: platelet-rich plasma (PRP), platelet-rich fibrin (PRF), fibrin gel polymerization and leukocytes.

In the field of platelet concentrates for surgical use, most products are termed Platelet-Rich Plasma (PRP). Unfortunately, this term is very general and incomplete, leading to many confusions in the scientific database. In this article, a panel of experts discusses this issue and proposes an accurate and simple terminology system for platelet concentrates for surgical use. Four main categories of products can be easily defined, depending on their leukocyte content and fibrin architecture: Pure Platelet-Rich Plasma (P-PRP), such as cell separator PRP, Vivostat PRF or Anitua's PRGF; Leukocyteand Platelet-Rich Plasma (L-PRP), such as Curasan, Regen, Plateltex, SmartPReP, PCCS, Magellan, Angel or GPS PRP; Pure Plaletet-Rich Fibrin (P-PRF), such as Fibrinet; and Leukocyte- and Platelet-Rich Fibrin (L-PRF), such as Choukroun's PRF. P-PRP and L-PRP refer to the unactivated liquid form of these products, their activated versions being respectively named P-PRP gels and L-PRP gels. The purpose of this search for a terminology consensus is to plead for a more serious characterization of these products. Researchers have to be aware of the complex nature of these living biomaterials, in order to avoid misunderstandings and erroneous conclusions. Understanding the biomaterials or believing in the magic of growth factors ? From this choice depends the future of the field.