Platelet-Rich Fibrin and its Emerging Therapeutic Benefits for Musculoskeletal Injury Treatment.

New therapies that accelerate musculoskeletal tissue recovery are highly desirable. Platelet-rich fibrin (PRF) is a leukocyte- and platelet-rich fibrin biomaterial that acts as a binding site for both platelets and growth factors. Through increasing the local concentration of growth factors at specific tissues, PRF promotes tissue regeneration. PRF has been frequently used in combination with bone graft materials to reduce healing times and promote bone regeneration during maxillofacial surgery. However, its benefits during muscle repair and recovery are less well-documented. Here, we perform a narrative review on PRF therapies and muscle injuries to ascertain its beneficial effects. We reviewed the factors that contribute to the biological activity of PRF and the published pre-clinical and clinical evidence to support its emerging use in musculoskeletal therapy. We include in vitro studies, in vivo animal studies and clinical articles highlighting both the success and failures of PRF treatment. PRF can promote the healing process when used in a range of orthopaedic and sports-related injuries. These include cartilage repair, rotator cuff surgery and anterior cruciate ligament surgery. However, conflicting data for these benefits have been reported, most likely due to inconsistencies in both PRF preparation protocols and dosing regimens. Despite this, the literature generally supports the use of PRF as a beneficial adjuvant for a range of chronic muscle, tendon, bone or other soft tissue injuries. Further clinical trials to confirm these benefits require consistency in PRF preparation and the classification of a successful clinical outcome to fully harness its potential.

About the Experimental and Virtual Analysis of Orthopedic Implant Systems for the Revision of the Hip Prosthesis with Morcellated Bone Graft and Reconstruction Net.

INTRODUCTION: Prosthesis loosening is an alteration of the function and position of a total hip prosthesis with reference to the initial surgical moment. The main mechanism unanimously accepted for aseptic prosthetic losses at the level of the cup is represented by the biological mechanism. MATERIAL AND METHOD: Experimental and virtual, interdisciplinary tools, techniques and methods were used to determine the behavior of the hip replacement prosthesis with the morcellated graft and the reconstruction net. Performing an orthopedic assembly with a morcellated bone graft and reconstruction net. An assembly was performed on a hip joint taken from an animal (cow). The biological material and the components of the prosthesis were prepared similarly to the revision prosthesis intervention. Experimental testing of orthopedic assembly with morcellated bone graft and reconstruction net. This assembly was tested on a universal machine to determine the maximum force at which it yields. This was 1790 Kgf, i.e. 17559 N. Virtual experimental testing of the hip joint with orthopedic revision assembly with a morcellated bone graft and reconstruction net for normal gait loading. The orthopedic assembly with the morcellated graft and the reconstruction net was reconstructed in the virtual environment. Normal load was used. Results maps were obtained. CONCLUSIONS: Analyzing the results from the two tests, experimental and virtual, and important conclusions were drawn regarding this orthopedic assembly.

Are Zirconia Bioceramics and Ceramics Intended to Come in Contact with Skin Inert?

Generally speaking, ceramic materials are insensitive to corrosion, compared to most other materials. The present study questions the fact that ceramics are inert. Two major aspects are to be considered: the stability of zirconia over time, the stable tetragonal phase transforming into an unstable monoclinic form; the multitude of manufacturing methods, using various additives, sintering additives, oxides mixing, impurities, grain boundaries, and porosities which strongly influence the corrosion behavior and chemical degradation. In case of the investigated ceramics two paths were pursued:a) Dissolutions of ceramics in a mixture of HNO3 60% and HF 40% ultrapure medium.b) Release of cations from ceramics in various mediums:dental bioceramics in a 0.07 M HCl medium and a 0.1% NaF+0.1% KF medium; ceramics used in jewelry and watchmaking applications in a HCl 0.07 M medium and an artificial sweat medium. By inductively coupled plasma-optical emission spectrometry/mass spectrometry (ICP-OES/MS), traces of significant chemical elements were assessed: Hf, Cr, Y, As, Pb, Al, Fe, Cu, Se, Sb, La, Ni, Co, Sb, Ta, Te, Ba, Sm, Nb, Hg, Cd, Sr, As and Se. In ceramics used in jewelry and watchmaking applications the concentrations found vary from one ceramic to another, including toxic elements such as Te, Ba, As, Pb, Sm, Hg and Cd, therefore being technical zirconia ceramics which are not intended for the medical field. For ceramics used in jewelry and watchmaking applications a screening identification test for Ni, Co, Cu and Fe with strips of type Merckoquant® (Merck, Kenilworth, NJ, USA) was also performed. The obtained data prove that the zirconia ceramics in question are far from being "inert".

The role of IgE specific for galactose-α-1,3-galactose in predicting cetuximab induced hypersensitivity reaction: a systematic review and a diagnostic meta-analysis.

Recombinant monoclonal antibodies are used for treating various diseases, from asthma, rheumatoid arthritis, and inflammatory bowel disease to cancer. Although monoclonal antibodies are known to have fewer toxic reactions compared with the conventional cytotoxic antineoplastic drugs, the cases of severe systemic hypersensitivity reaction (HSR) should be acknowledged. Our aim was to assess the diagnostic accuracy of the anti-IgE for galactose-α-1,3-galactose in patients with HSRs to cetuximab. We searched in PubMed, Cochrane Library, Scopus, and World of Science databases to July 1st, 2020. We included a total of 6 studies, with 1074 patients. Meta-analysis was performed using bivariate analysis and the random-effect model. The pooled sensitivity was 73% (95% CI 62-81%) and the pooled specificity was 88% (95% CI 79-94%). We had not found significant heterogeneity and, despite some discrepancies in the nature of data available in the analysed studies, we draw the conclusion that the presence of cetuximab specific IgE (anti cetuximab antibody) and/or galactose-α-1,3-galactose shows moderate to high sensitivity and specificity of developing an HSR. More studies are needed to establish a protocol necessary for the proper prediction and avoidance of HSR related to cetuximab.

Corrosion Resistance of Stainless Steels Intended to Come into Direct or Prolonged Contact with the Skin.

The biocompatibility of materials in contact with a living tissue becomes a puzzle in the overall picture of assessing the toxic effects of chemicals that come into contact with us. Allergic reactions to substances are a significant and growing health problem affecting large parts of the population in Europe. Wristwatches are objects worn in prolonged contact with the skin, being subject to localized corrosion, especially pitting and crevice types, in sulfide-chloride medium, and high wear in the bracelets joints. Watches of medium quality are usually made of stainless steels. The X2 CrNiMo 17-12-2 316L grade as well as X1 CrNiMo 20-25-5 Cu 1 or 904L are commonly used, having good resistance to generalized corrosion. The passive layer is nevertheless insufficient to ensure complete immunity in all cases of localized corrosion encountered during wear. For this reason, a high-corrosion-resistant steel: X1 CrNiMo 18-15-4 N 0.15 or 317LMN, from three different suppliers was evaluated. Metallographic characterization was carried out. The corrosion behavior evaluation was performed for the generalized corrosion, pitting and crevice corrosion and galvanic corrosion. Galvanic couples steel 317LMN-gold 18K alloy 3N and gold 18K 5M were used. The results of the generalized and pitting corrosion test indicated three basic groups. All of the 317LMNs were similar. The 316L variants tested noticeably worse. The 904Ls were difficult to discern, but certainly easier than the 316Ls and, possibly, at least comparable to the 317LMNs.

Histological aspects of full-thickness skin grafts augmented with platelet-rich fibrin in rat model.

BACKGROUND AND OBJECTIVES: The restoration of the damaged tissue commences very early with a regulated sequence of biochemical events set into motion to repair the damage. While the understanding of this entire process is still incomplete, it has been established that platelets play a decisive role not only in hemostasis, but also in the wound healing process, through an abundance of growth factors and other signaling cytokines modulating the inflammatory response. To this end, we attempted to evaluate the effect of a platelet-rich biomaterial - platelet-rich fibrin (PRF) - in the augmentation of full-thickness skin grafts (FTSGs). MATERIALS AND METHODS: Skin defects were performed on the rats' dorsum and covered with FTSGs. The test group wound bed was treated with PRF before the suture of the graft. Skin graft specimens were obtained from the control and test group rats for histological and immunohistochemical examination on the 21st postsurgical day. Our study included 40 male Wistar rats. Average thickness of epidermal cell layers was recorded for each wound site. The average fibroblast count was compared between the control and test (PRF-augmented FTSG) groups. Blood vessel count and vascular density - the blood vessels were identified under low-power microscopy. The prominent vascular areas were then scanned in higher-power fields; individual vessels were marked and counted by hand. Vascular density was calculated. Mean vascular count for each graft was then calculated. RESULTS: The mean thickness of the epidermal layer was significantly higher and closer to the physiological epidermal thickness, in the test group than in the control group. The average fibroblast and fibrocyte count in the dermal layer in FTSGs augmented with PRF was higher than in the control group. We discovered a statistically insignificant increase in the blood vessel count and vascular density of the test group, compared to the control group. CONCLUSIONS: Our limited data supports the theory that the addition of PRF to FTSG recipient wound beds has the potential to improve graft take and regulate the proliferation of a thicker and more uniform epidermis, while decreasing healing time and dermal necrosis rates.

Histological findings from rat calvaria defect augmented with platelet-rich fibrin by using two consecutive periosteal incisions.

BACKGROUND AND OBJECTIVES: Platelet-rich fibrin (PRF) is a new generation of biomaterial that proved to be an effective tool in numerous clinical uses. This study aims at expanding the range effectiveness of PRF in promoting bone healing by histological evaluation. MATERIALS AND METHODS: We performed a pair of two calvaria defects on 35 Wistar rats. The left defect was left empty as a control and the right defect was augmented with PRF. After 45 days, the experiment was terminated and the calvaria were collected and underwent morphological and histological analysis. RESULTS: New bone formations have been shown to be prevalent in the PRF augmented defect. CONCLUSIONS: PRF increases the body's natural ability to heal and regenerate bone.