Investigating the effect of age on platelet ultrastructure using transmission electron microscopy.

In the present study, the age- and sex-related differences in platelet ultrastructure were investigated using transmission electron microscopy (TEM). A total of 15 healthy volunteers were grouped according to age, with 5 people in each of the following groups: young group (25-45 years), middle-aged group (46-65 years), and old-aged group (> 65 years). In the TEM micrographs, the internal components, specifically the α-granules, dense granules, and lysosomal granules, of 20 platelets were counted for each group. Two-way analysis of variance of age and sex variance was used to compare the results. The ultrastructure of the platelets in the old-aged group was observed to be quite different from those of the young and middle-aged groups. Specifically, with ageing, the platelet membrane becomes more irregular in shape and non-smooth, and multiple platelet membrane ruptures are observed. Furthermore, the pseudopodia and protuberances become more numerous and slender, and the number of α-granules is significantly reduced. These morphological changes indicate that ageing may affect the function of platelets, which in turn affects the efficacy of platelet concentrates. Thus, the effects of age should be considered when using platelet concentrates prepared from elderly autologous blood.

Application of standardized platelet-rich plasma in elderly patients with complex wounds.

In recent years, autologous platelet-rich plasma (PRP) derivatives have been used widely in the regeneration and repair of tissue, but a standard definition and preparation method for PRP are lacking. We developed a standardized method using platelet indices as quality-control indicators for PRP preparation. Twenty-one elderly patients (9 males, 12 females) with complex wounds were treated with standardized platelet-rich plasma (S-PRP). The platelet count in PRP after the second centrifugation was 1,069-1,436 × 109 /L. We adjusted the platelet concentration in PRP after a second centrifugation to 1,000 × 109 /L according to a formula using platelet-poor plasma (PPP). The standardized preparation method that we developed gave S-PRP with a relatively uniform platelet concentration. The wounds of 21 patients showed accelerated healing after S-PRP treatment, and there were no obvious side effects during treatment. These data suggest that our preparation method of S-PRP, using platelet indices as quality-control indicators with platelet count of 1,000 × 109 /L could be used for the treatment of complex wounds in the elderly. The preparation method of S-PRP proposed in the present study may be a simple and effective method of PRP quality control.

Application of plasma-combined regeneration technology in managing facial acne scars.

BACKGROUND AND OBJECTIVES: Plasma skin regeneration (PSR) and platelet-rich plasma（PRP） have gained popularity in the treatment of acne scars due to their efficacy and improved tolerability. The objective of this investigation was to evaluate the synergistic effect of PRP plus PSR (plasma-combined regeneration technology, PCRT) in managing facial acne scars. METHODS: From March 2015 to June 2017，a total of 25 cases with facial atrophic acne scars were treated with PCRT treatment for three to five times. Treatments were repeated at an interval of 8 weeks．Treatment parameters were titrated to an immediate end point of moderate erythema. The clinical end point for cessation of treatment was the attainment of satisfactory clinical results. Results were monitored photographically up to 6 months after treatment. The efficacy and adverse effects were evaluated by using the following outcome parameters： the duration of edema,erythema and crusting; the degree of hyperpigmentation, hypopigmentation and scarformation; subjective effective rate was evaluated by patients and physicians. RESULTS: 22 of 25 participants completed the study, and were followed up for 6-12 months. After three to five treatments, evaluation by patients showed that the total effective rate was 90.91%. Evaluation by two physicians showed that the total effective rate was 86.36%. Treatment was well tolerated by all participants. The total duration of side effects was 6.7 ± 1.7 days of edema, 8.1 ± 2.3 days of erythema,6.5 ± 1.8 days of crusting, respectively. No hyperpigmentation, depigmentation, and worsening of scarring were observed by the conclusion of the follow-up period． Conclusion: These results provide initial evidence for the safety and effectiveness of PCRT as a well-tolerated modality for the treatment of acne scars. PCRT is an ideal treatment for facial acne scars with minimal side effect．.

The effects of aging, diabetes mellitus, and antiplatelet drugs on growth factors and anti-aging proteins in platelet-rich plasma.

As the aged population continues to markedly increase worldwide, the incidences of diabetes mellitus (DM) and cardiovascular disease (CVD) are increasing. In this study, we investigated the effects of aging, DM, and antiplatelet drugs on growth factors and anti-aging proteins in platelet-rich plasma (PRP). The study participants were classified into the following four groups: Group A, healthy individuals aged ≤45 years; Group B, healthy individuals aged >45 years; Group C, DM patients aged >45 years; and Group D, CVD patients aged >45 years taking antiplatelet drugs. The concentrations of epidermal growth factor (EGF), fibroblast growth factor (FGF)-2, platelet-derived growth factor (PDGF)-AA, PDGF-AB/BB, vascular endothelial growth factor (VEGF)-A, tissue inhibitor of metalloproteinase 2 (TIMP2), insulin-like growth factor 1 (IGF-1), growth differentiation factor (GDF)11, and clusterin in PRP samples were determined to analyze the effects of aging, DM, and antiplatelet drugs. Overall, the concentrations of IGF-1, TIMP2, and clusterin did not vary significantly between the four groups. The concentrations of PDGF-AB/BB (P = 0.010), VEGF-A (P = 0.000), and GDF11 (P = 0.026) were significantly different between Group A and Group B. Further, the concentrations of EGF (P = 0.000) and GDF11 (P = 0.000) were significantly different between Groups B and C. The concentrations of EGF (P = 0.001), VEGF-A (P = 0.000), and GDF11 (P = 0.002) significantly differed between Groups A and C. The concentrations of FGF-2 (P = 0.048), PDGF-AA (P = 0.03), and GDF11 (P = 0.001) were significantly different between Groups B and D. The concentrations of PDGF-AB/BB (P = 0.032), VEGF-A (P = 0.010), and GDF11 (P = 0.02) significantly differed between Groups A and D. We found that PRP contains high concentrations of the growth factors, TIMP2 and GDF11. Aging, DM, and antiplatelet drugs can decrease the concentration of some growth factors and GDF11, which weakens the regenerative capacity and anti-aging effects of PRP and reduces the quality of PRP.