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1.
目的 确定激活剂凝血酶与富血小板血浆(PRP)混合的最适比例,并探讨凝血酶与PRP中血小板衍生生长因子.AB(PDGF.AB)和转化生长因子-β(TGF-β)对人骨髓基质干细胞(hBMSCs)增殖的联合作用.方法 按1000 U凝血酶溶于1 mL质量百分比为10%的CaCl2配制激活剂.按PRP与激活剂混合比例为1:1、5:1、10:1、20:1、40:1分为A、B、C、D、E 5组.ELISA法测定各组0、1、8、24、120 h后PRP凝胶中PDGF-AB、TGF-β1的浓度;MTT法评价各组PRP凝胶上清对hBMSCs增殖的影响.结果 PRP与凝血酶混合后,PDGF-AB、TGF-β1浓度立即升高,在激活1 h后达到高峰.B、C、D组PRP凝胶中PDGF-AB、TGF-β1的浓度最高,并明显促进hBMSCs的增殖;而A组则抑制hBMSCs的增殖.结论 PRP对hBMSCs增殖的作用与其所含有PDGF-AB、TGF-β1存在浓度依赖性,而凝血酶可能在一定浓度范尉内主要通过对PRP中生长因子浓度的调控来影响hBMSCs的增殖,但是当凝血酶浓度过高时则抑制hBMSCs的增殖.  相似文献   

2.

Background

The purpose of the study is to investigate whether autologous platelet-rich plasma (PRP) can serve as bone-inducing factors to provide osteoinduction and improve bone regeneration for tissue-engineered bones fabricated with bone marrow mesenchymal stem cells (MSCs) and beta-tricalcium phosphate (β-TCP) ceramics. The current study will give more insight into the contradictory osteogenic capacity of PRP.

Methods

The concentration of platelets, platelet-derived growth factor-AB (PDGF-AB), and transforming growth factor-β1 (TGF-β1) were measured in PRP and whole blood. Tissue-engineered bones using MSCs on β-TCP scaffolds in combination with autologous PRP were fabricated (PRP group). Controls were established without the use of autologous PRP (non-PRP group). In vitro, the proliferation and osteogenic differentiation of MSCs on fabricated constructs from six rabbits were evaluated with MTT assay, alkaline phosphatase (ALP) activity, and osteocalcin (OC) content measurement after 1, 7, and 14 days of culture. For in vivo study, the segmental defects of radial diaphyses of 12 rabbits from each group were repaired by fabricated constructs. Bone-forming capacity of the implanted constructs was determined by radiographic and histological analysis at 4 and 8 weeks postoperatively.

Results

PRP produced significantly higher concentration of platelets, PDGF-AB, and TGF-β1 than whole blood. In vitro study, MTT assay demonstrated that the MSCs in the presence of autologous PRP exhibited excellent proliferation at each time point. The results of osteogenic capacity detection showed significantly higher levels of synthesis of ALP and OC by the MSCs in combination with autologous PRP after 7 and 14 days of culture. In vivo study, radiographic observation showed that the PRP group produced significantly higher score than the non-PRP group at each time point. For histological evaluation, significantly higher volume of regenerated bone was found in the PRP group when compared with the non-PRP group at each time point.

Conclusions

Our study findings support the osteogenic capacity of autologous PRP. The results indicate that the use of autologous PRP is a simple and effective way to provide osteoinduction and improve bone regeneration for tissue-engineered bone reconstruction.
  相似文献   

3.
Background and purpose — In 3 papers in Acta Orthopaedica 10 years ago, we described that platelet-rich plasma (PRP) improves tendon healing in a rat Achilles transection model. Later, we found that microtrauma has similar effects, probably acting via inflammation. This raised the suspicion that the effect ascribed to growth factors within PRP could instead be due to unspecific influences on inflammation. While testing this hypothesis, we noted that the effect seemed to be related to the microbiota.

Material and methods — We tried to reproduce our old findings with local injection of PRP 6?h after tendon transection, followed by mechanical testing after 11 days. This failed. After fruitless variations in PRP production protocols, leukocyte concentration, and physical activity, we finally tried rats carrying potentially pathogenic bacteria. In all, 242 rats were used.

Results — In 4 consecutive experiments on pathogen-free rats, no effect of PRP on healing was found. In contrast, apparently healthy rats carrying Staphylococcus aureus showed increased strength of the healing tendon after PRP treatment. These rats had higher levels of cytotoxic T-cells in their spleens.

Interpretation — The failure to reproduce older experiments in clean rats was striking, and the difference in response between these and Staphylococcus-carrying rats suggests that the PRP effect is dependent on the immune status. PRP functions may be more complex than just the release of growth factors. Extrapolation from our previous findings with PRP to the situation in humans therefore becomes even more uncertain.  相似文献   

4.
5.
Autologous platelet‐rich plasma (PRP) exerts positive therapeutic effects on hair thickness and density in patients with pattern hair loss. The aim of our study was to evaluate the efficacy of intra‐perifollicular autologous PRP and polydeoxyribonucleotide (PDRN) injections in treating female pattern hair loss (FPHL). Twenty FPHL patients were treated with a single session of PRP injection, followed by 12 sessions of PDRN intra‐perifollicular injection, along the scalp at weekly intervals. Additionally, another 20 FPHL patients were treated with 12 sessions of PDRN injection only. Meanwhile, one half of the backs of two rabbits was injected with the PRP preparation, while the other half was injected with phosphate buffered saline as a control. Tissue samples from the rabbits were analyzed by real‐time polymerase chain reaction and Western blotting. Compared with baseline values, patients treated with PRP and PDRN injections exhibited clinical improvement in mean hair counts (23.2 ± 15.5%; p < 0.001) and mean hair thickness (16.8 ± 10.8%; p < 0.001). In addition, patients treated with the 12 sessions of intra‐perifollicular PDRN injection alone also showed clinical improvement in mean hair counts (17.9 ± 13.2%; p < 0.001) and mean hair thickness (13.5 ± 10.7%; p < 0.001). Comparison analyses between the two groups revealed that combined therapy with PRP and PDRN induces greater improvement in hair thickness than treatment with PDRN therapy alone (p = 0.031), but not in hair counts (p > 0.05). The pilot animal study revealed significant up‐regulation of WNT, platelet‐derived growth factor, and fibroblast growth factor expression in rabbit skin treated with the PRP preparation, compared with control skin. In conclusion, intra‐perifollicular injections of autologous PRP and/or PDRN generate improvements in hair thickness and density in FPHL patients.  相似文献   

6.
This study aimed to evaluate growth factor concentration in platelet-rich plasma (PRP) (leukocyte-rich PRP) based on storage temperature, duration of storage, and method of activation. PRP samples were stored at 24℃ (room temperature group), 4℃ (refrigerator group), and −70℃ (deep-freezer group). In each temperature, four aliquots were prepared based on the time of analysis (immediately, 1, 3, and 7 days after preparation). After storage, concentrations of platelet-derived growth factor-AA (PDGF-AA), transforming growth factor-β (TGF-β), vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), and fibroblast growth factor-basic (FGF-B) were assessed with/without activation using Quantikine colorimetric sandwich immunoassay kits. PRP was activated with 10% Triton-X for PDGF-AA, VEGF, FGF-B, IGF-1 measurement and sonication for TGF-β1 measurement. Without activation, PDGF-AA concentration was highest on day 7 in the room temperature group. With activation, the concentration of PDGF-AA was constant over the observation period at all temperatures. Without activation, the TGF-β1 concentration remained negligible over the observation period at all temperatures. However, with activation, TGF-β1 gradually increased to its highest concentration on day 7 at all temperatures. Over the observation period, VEGF and IGF-1 concentrations were constant with and without activation at all temperatures. Without activation, FGF-B concentration increased, with the highest concentration observed on day 7 in the deep-freezer group. With activation, FGF-B concentration decreased after day 1 in the room temperature group. Growth factor concentration in PRP differed significantly based on storage temperature, duration of storage, and method of activation. Appropriate storage conditions and activation are important to optimize its effects on desired clinical outcomes. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:777-784, 2020  相似文献   

7.

Background

In addition to a stabile osteosynthesis autologous cancellous bone graft remains an essential therapy option in persistent non-union. Despite this therapy regimen persistent non-union can occasionally occur. The aim of this study was to evaluate the treatment of persistent non-union with a combination of platelet-rich plasma (PRP) and autologous cancellous bone.

Material and methods

In this prospective study 17 patients with persistent non-union of long bones were treated by a combination of PRP and autologous iliac crest bone. Inclusion criteria were a minimum of one previously failed cancellous bone transplantation and an atrophic non-union persisting for 6?C14?months (mean 9?months). The patients were examined clinically and radiologically at intervals of 3, 6 and 9?months postoperatively.

Results

After an average time of 17?months (range 15?C23?months) the patients were treated by a combination of PRP and autologous cancellous bone. In all cases the non-union was successfully treated and osseous bridging was found radiologically after an average of 5?months (range 4?C7?months) without any complications.

Conclusion

The combination of PRP and autologous cancellous bone appears to be a safe and effective method for treatment of persistent non-union. The use of PRP does not result in substantial additional costs. Allergies and graft versus host reactions are not expected because of the autologous origin.  相似文献   

8.
《Injury》2018,49(6):1052-1057
BackgroundThere is evidence showing that human mesenchymal stromal cells (MSC) seeded on collagen microspheres (CM) and incorporated into platelet rich plasma (PRP) clots induce bone formation. For clinical trials it is very important to establish standardization of storage and shipment conditions to ensure the viability and functionality of cellular products. We investigate the effect of storage temperature and time on the viability and functionality of human MSC seeded on CM and included into PRP clots for using in the further clinical application for bone regeneration.MethodsMSC/CM/PRP clots were stored at room temperature (RT), 4 °C and 37 °C for 12 h, 24 h and 48 h. At each period of time, MSC were evaluated for their viability and functionality.ResultsMSC from MSC/CM/PRP clots maintained at RT and 37 °C for 24 h showed a high viability (90%) and maintained their capacity of proliferation, migration and osteogenic differentiation. In contrast, MSC/CM/PRP maintained to 4 °C showed a significant reduction in their viability and migration capacity. MSC from MSC/CM/PRP clots maintained at RT for 24 h induce osteogenesis in the subcutaneous tissues of mice, after four months of transplantation.DiscussionOur results show that MSC incorporated into CM/PRP clots and maintained at RT can be utilized in bone regeneration protocols during the first 24 h after their processing.  相似文献   

9.
Background: In cases of congenital chest wall deformities, it is important to maintain the flexibility of the chest wall after rib cartilage resection. In this study, we aimed to determine the regeneration capability of cartilage and the effects of platelet-rich plasma (PRP) on the regeneration process.

Methods: A total of 16 four-week-old New Zealand rabbits were used in this study. In the 4th–5th right costal cartilages, the perichondrial sheaths were dissected and costal cartilages were excised. Then, the perichondrial sheaths were closed with absorbable material in the sham group (n?=?8), and this was done after replacing PRP in the PRP group (n?=?8). The left costal cartilages of the animals were used as controls. The volumes of the costal cartilages and their perichondrial sheaths were estimated using Cavalieri’s principle. In addition, the mean numerical densities of the chondroblasts and chondrocytes per square millimetre were estimated using unbiased counting frames.

Results: In the PRP and sham groups, the volumes of the cartilages and perichondrial sheaths were higher than those of the control group (p?p?Conclusions: Applying PRP after resection may provide better healing and faster regeneration of cartilage.  相似文献   

10.
The aim of this study was to investigate the effect of platelet-rich plasma (PRP) on the proliferation of osteoblast-like cells in vitro. PRP was prepared using a centrifuge; the number of platelets (n = 32) and the levels of platelet-derived growth factor-AB (PDGF-AB), transforming growth factor-beta1 (TGF-beta1), and insulin-like growth factor-I (IGF-I) were measured (n = 16). For the proliferation assay, SaOS-2 was cultured in the presence of platelet-poor plasma (PPP), whole blood, or PRP. The cell number was counted after 36 and 72 hours. To investigate the effect of each growth factor, the cells were cultured with PRP in the absence or presence of neutralizing antibodies, and counted as described. The mean platelet count of PRP was 1546.36 +/- 382.25 x 10(3)/microL, and the mean levels of PDGF-AB, TGF-beta1 and IGF-I were 0.271 +/- 0.043, 0.190 +/- 0.039, and 0.110 +/- 0.039 ng/1500 x 10(3) platelets, respectively. Cell proliferation was enhanced in all PRP groups in a dose-dependent manner, and all neutralizing antibodies significantly suppressed proliferation compared with the PRP group, lacking antibody, at 36 hours. However, at 72 hours, the neutralizing antibodies of PDGF and TGF-beta1, but not IGF-I, significantly suppressed proliferation. These results show the beneficial abilities of PRP in the proliferation of osteoblast-like cells from the standpoint of growth factors, including the contribution of each factor.  相似文献   

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