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BACKGROUND: Platelet-rich plasma (PRP) has been used in different non-transfusion indications due to its role in tissue regeneration and healing. The aim of this overview of systematic reviews (umbrella review) is to provide a summary of the existing research syntheses related to PRP use for sports-related muscle, tendon and ligament injuries. MATERIALS AND METHODS: Literature searches were performed in MEDLINE, Embase, and Cochrane Library to identify systematic reviews focusing on PRP use for sports-related muscle, tendon and ligament injuries. The methodological quality of included studies was assessed using the checklist for systematic reviews and research syntheses developed by the Joanna Briggs Institute and the GRADE assessment. RESULTS: Twenty-two studies met the inclusion criteria. Five studies evaluated PRP use for acute muscle injury, and 17 evaluated PRP use for tendon and ligament injury. Studies were heterogeneous in terms of the dose and number of PRP injections, and the control groups. Three of the 5 reviews evaluating acute muscle injury concluded that PRP had no effect on the outcomes considered. One review shows superior efficacy of rehabilitation exercise compared to PRP. One review shows that PRP may result in an earlier return to sport for acute grade I-II injury. Eight out of the 17 reviews evaluating PRP for tendon and ligament injuries show a statistically significant (p

BACKGROUND: The aim of this systematic review and meta-analysis was to evaluate the benefit of platelet rich plasma (PRP) in oral surgery. MATERIALS AND METHODS: We performed a systematic search of the literature. The GRADE system was used to assess the certainty of the body of evidence. RESULTS: We found 21 randomised controlled trials that met our inclusion criteria: 12 studies included patients with periodontal defects, five studies focused on healing of extraction sockets, three studies on sinus lift augmentation, and one study on periapical osseous defects. However, for the quantitative synthesis (meta-analysis), we evaluated “periodontal defects” studies only, since for other clinical contexts the number of studies were too low and the procedural heterogeneity was too high to allow pooling of data. PRP-containing regimens were compared to non-PRP-containing regimens. Primary outcomes for the evaluation of periodontal defects were probing depths, clinical attachment level, gingival recession, and radiographic bone defect. It is not usually clear whether or not the use of PRP compared to controls affects “probing depth” at long-term follow up; the between group differences were small and unlikely to be of clinical importance (i.e., very low quality of evidence). For the other outcomes analysed (“clinical attachment levels”, “gingival recession”, “bony defect”), we observed a very slight marginal clinical benefit of PRP compared to controls. The available evidence for these comparisons was rated as low quality as most of the studies selected showed inconsistency, imprecision, and risk of bias. DISCUSSION: Evidence from a comparison between the use in oral surgery of PRP-containing regimens compared to other regimens not-containing PRP was of low quality. The results of the meta-analysis, limited to studies in patients with periodontal defects, document that PRP was slightly more effective compared to controls not-containing PRP.

The phenomenon of self-organization of domains into a “square-net pattern” in single-crystal, flux-grown BaTiO3 several degrees below the ferroelectric to paraelectric phase transition was investigated using in situ synchrotron x-ray topography. The tetragonal distortion of the crystal was determined by measuring the angular separation between the diffraction images received from 90° a and c domains in the projection topographs, and shows a rapid decrease towards 110 °C, the onset temperature for self-organization. The onset of self-organization is accompanied by bending of the {100} lattice planes parallel to the crystal surface, which produces a strain that persists up to and beyond the Curie temperature, where the crystal becomes cubic and the self-organized domains disappear. At the Curie point, the bending angle α100 = 8.1(±0.3) mrad is at a maximum and corresponds to the radius of curvature of the surface being 16.3(±0.6) mm.

In the marrow, macrophages form a morphological unit, the erythroblast island and in culture release factors still to be marked that affect the growth of the erythroblasts(Ery).When blood CD34pos are stimulated with dexamethasone(Dex) and growth factors in human erythroid massive amplification(HEMA)cultures, large numbers of Ery are generated which remain immature and proliferate for 10-17 days. Dex withdrawl and erythropoietin(EPO)exposure induce Ery to activate the maturation program within 24-48 h.At day 13-14 of HEMA. The role of macrophages in HEMA has not been investigated. Live contrast-phase microscopy(10x magnify.;timelapses: 1 frame/30”recorded for 8-10h)was used to visualize interactions between Ery and macrophages in day 13-14 HEMA with or without Dex and in cultures in which day 13-14 progeny were exposed to EPO alone. Macrophages and Ery at different stages of maturation were recognized on the basis of size, chromatin condensation state, motility and frequency using data previously obtained by FACS as comparison. Day14 without Dex: Ery at all maturation stages were observed moving in a coordinate fashion but with frequent changes in directions. Ery formed few, loose and unstable aggregates. Macrophages were rare and moved independently from Ery.Day14 with Dex: Ery moved synchronously toward each other forming large and stable aggregates. Macrophages were “fat”, highly motile and extended short protrusions which established transient contacts with hundreds/thousands of Ery over 1 h. Contacts involved both isolated Ery (interactions, “loose”)or clusters of Ery at all maturation stages(interactions “tight”). In the first 45’of observation,~45% of the interactions were loose,~23% were a combination of loose and tight and~35%were tight. By 1-2h,25% were loose,50% were loose and tight and 25% were tight. Cytokinesis involved single and double proEry. The process lasted 5’ and was not associated with macrophages. Dex withdrawal and EPO exposure induced noticeable changes.By15’,macrophages became greatly motile engaging in fewer “loose” interactions( 5-9%)and in more “tight” interactions. By 60’,86%of the interactions were “tight” and involved preferentially clusters of mature Ery (>80%).Mega-aggregates including 2-6 macrophage-Ery clusters each were also observed., Italian Journal of Anatomy and Embryology, Vol 119, No 1 (Supplement) 2014