BackgroundThe development of platelet-rich fibrin (PRF) drastically simplified the preparation procedure of platelet-concentrated biomaterials, such as platelet-rich plasma (PRP), and facilitated their clinical application. PRF’s clinical effectiveness has often been demonstrated in pre-clinical and clinical studies; however, it is still controversial whether growth factors are significantly concentrated in PRF preparations to facilitate wound healing and tissue regeneration. To address this matter, we performed a comparative study of growth factor contents in PRP and its derivatives, such as advanced PRF (A-PRF) and concentrated growth factors (CGF).MethodsPRP and its derivatives were prepared from the same peripheral blood samples collected from healthy donors. A-PRF and CGF preparations were homogenized and centrifuged to produce extracts. Platelet and white blood cell counts in A-PRF and CGF preparations were determined by subtracting those counts in red blood cell fractions, supernatant acellular serum fractions, and A-PRF/CGF exudate fractions from those counts of whole blood samples. Concentrations of growth factors (TGF-β1, PDGF-BB, VEGF) and pro-inflammatory cytokines (IL-1β, IL-6) were determined using ELISA kits.ResultsCompared to PRP preparations, both A-PRF and CGF extracts contained compatible or higher levels of platelets and platelet-derived growth factors. In a cell proliferation assay, both A-PRF and CGF extracts significantly stimulated the proliferation of human periosteal cells without significant reduction at higher doses.ConclusionsThese data clearly demonstrate that both A-PRF and CGF preparations contain significant amounts of growth factors capable of stimulating periosteal cell proliferation, suggesting that A-PRF and CGF preparations function not only as a scaffolding material but also as a reservoir to deliver certain growth factors at the site of application.

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This purpose of this study was to investigate the relationship between quality of life and psychiatric impairment in a Taiwanese community located near the epicenter of the 1999 earthquake, as assessed four to six months after the natural catastrophe. Trained assistants interviewed the 4223 respondents using the disaster-related psychological screening test (DRPST), an instrument specifically designed and validated by senior psychiatrists for assessment of psychiatric impairment after natural catastrophe. Additionally, the 36-Item Short-Form Health Survey (SF-36) was used to evaluate quality of life. The collected results were analyzed using Windows SPSS 10.0 software. Psychiatric impairment rated moderate to severe was assessed for 1448 (34.3%) of the responding residents. The 4223 respondents were divided into 4 psychiatric-impairment groups based on DPRST score: healthy (n = 952); mild impairment (n = 1823); moderate impairment (n = 1126); and, severe impairment (n = 322). The four groups were compared for a number of salient factors, including gender, age, current marital status and psychiatric-impairment score, to determine impact on quality of life. Respondents assessed as psychiatrically impaired tended to be older, female, divorced/widowed, and less educated, and they were more likely to have experienced major familial financial loss as an immediate consequence of the earthquake. Further, the greater the severity of the psychiatric impairment, the lower the scores for quality of life, for both the physical and mental aspects of this important general indicator.

The aim of the present study was to survey a cohort population for the risk factors of post-traumatic stress disorder (PTSD) and major depression, and the prevalence of different psychiatric disorders at 6 months and 2 and 3 years after a major earthquake. The Disaster-Related Psychological Screening Test (DRPST), part I, and the Mini-International Neuropsychiatric Interview (MINI) were, respectively, administered by trained interviewers and psychiatrists in this communityinterview program. The prevalence of PTSD decreased from 8.3% at 6 months to 4.2% at 3 years after the earthquake. Suicidality increased from 4.2% at 6 months and 5.6% at 2 years to 6.0% at 3 years after the earthquake; drug abuse/dependence increased from 2.3% at 6 months to 5.1% at 3 years after the disaster. The risk factors for PTSD and major depression in various post-disaster stages were determined. Earthquake survivors had a high percentage of psychiatric disorders in the first 2 years, and then the prevalence declined. Following the devastation caused by the Chi-Chi earthquake, it is important to focus on treating symptoms of major depression and PTSD and eliminating the risk factors for both of these disorders in survivors to avoid the increase in suicidality.

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