PRF was shown to improve soft tissue generation and limit dimensional changes post-extraction, with little available data to date supporting its use in GBR.

The findings from the present study demonstrate that a potent formulation of liquid platelet concentrates could be obtained without use of anti-coagulants.

The findings from the present study demonstrate modifications to centrifugation speed and time with the low-speed concept favor an increase in growth factor release from PRF clots. This, in turn, may directly influence tissue regeneration by increasing fibroblast migration, proliferation, and collagen mRNA levels. Future animal and clinical studies are now necessary.

The growing multidisciplinary field of tissue engineering aims at predictably regenerating, enhancing, or replacing damaged or missing tissues for a variety of conditions caused by trauma, disease, and old age. One area of research that has gained tremendous awareness in recent years is that of platelet-rich fibrin (PRF), which has been utilized across a wide variety of medical fields for the regeneration of soft tissues. This systematic review gathered all the currently available in vitro, in vivo, and clinical literature utilizing PRF for soft tissue regeneration, augmentation, and/or wound healing. In total, 164 publications met the original search criteria, with a total of 48 publications meeting inclusion criteria (kappa score = 94%). These studies were divided into 7 in vitro, 11 in vivo, and 31 clinical studies. In summary, 6 out of 7 (85.7%) and 11 out of 11 (100%) of the in vitro and in vivo studies, respectively, demonstrated a statistically significant advantage for combining PRF to their regenerative therapies. Out of the remaining 31 clinical studies, a total of 8 reported the effects of PRF in a randomized clinical trial, with 5 additional studies (13 total) reporting appropriate controls. In those clinical studies, 9 out of the 13 studies (69.2%) demonstrated a statistically relevant positive outcome for the primary endpoints measured. In total, 18 studies (58% of clinical studies) reported positive wound-healing events associated with the use of PRF, despite using controls. Furthermore, 27 of the 31 clinical studies (87%) supported the use of PRF for soft tissue regeneration and wound healing for a variety of procedures in medicine and dentistry. In conclusion, the results from the present systematic review highlight the positive effects of PRF on wound healing after regenerative therapy for the management of various soft tissue defects found in medicine and dentistry.

Isocoumarins are potent mechanism-based heterocyclic irreversible inhibitors for a variety of serine proteases. Most serine proteases are inhibited by the general serine protease inhibitor 3,4-dichloroisocoumarin, whereas isocoumarins containing hydrophobic 7-acylamino groups are potent inhibitors for human leukocyte elastase and those containing 7-alkylureidogroups are inhibitors for procine pancreatic elastase. Isocoumarins containing basic side chains that resemble arginine are potent inhibitors for trypsin-like enzymes. A number of 3-alkoxy-4-chloro-7-guanidinoisocoumarins are potent inhibitors of bovine thrombin, human factor Xa, human factor XIa, human factor XIIa, human plasma kallikrein, porcine pancreatic kallikrein, and bovine trypsin. Another cathionic derivative, 4-chloro-3-(2-isothiureidoethoxy) isocoumarin, is less reactive toward many of these enzymes but is an extremely potent inhibitor of human plasma kallikrein. Several guanidinoisocoumarins have been tested as anticoagulants in human plasma and are effective at prolonging the prothrombin time. The mechanism of inhibition by this class of heterocyclic inactivators involves formation of an acyl enzyme by reaction of the active site serine with the isocoumarin carbonyl group. Isocoumarins with 7-amino or 7-guanidino groups will then decompose further to quinone imine methide intermediates, which react further with an active site residue (probably His-57) to form stable inhibited enzyme derivatives. Isocoumarins should be useful in further investigations of the physiological function of serine proteases and may have future therapeutic utility for the treatment of emphysema and coagulation disorders.