OBJECTIVE: To study the effect of platelet-rich plasma in the repair of bone defect. METHODS: Segmental bone defects of 1 cm were created in the mid-upper part of bilateral radius of 24 New Zealand white rabbits. One side was randomly chosen as the experimental side, which was filled with artificial bone with platelet-rich plasma (PRP). The other side filled with artificial bone without PRP as the control. After 2, 4, 8 and 12 weeks of implantation, the gross, radiological, histological observations, and computer graphic analysis were performed to investigate the bone healing of the defect in both sides. RESULTS: Two weeks after operation, new bone and fibrous tissue formation in both the experimental and the control sides were observed only in the areas adjacent to the cut ends of the host bone, but the amount of new tissue in the experimental side was much more than that in the control side. In the 4th and 8th weeks, the surface of the artificial bone was covered with a large amount of new bones, the artificial bone was bridged tightly with the host bone by callus in the experimental side, while new bone was limited mainly in the cut ends and was less mature in the control side. In the 12th weeks, bone defects were entirely healed in the experimental side, which were covered completely with cortical bone, while new bone formation was only observed in the ends of artificial bone and there were not continuous bone callus on the surface in the control side. CONCLUSION: Artificial bone with PRP is effective in the repair of segmental bone defects, and PRP could improve the healing of bone defect.
Objective To study the mechanism of compound of calcium phosphate(TCP) and platelet-rich plasma(PRP) in the treatment of femoral head necrosis.Methods The left femoral heads of 48 New Zealand white rabbits were frozen by liquid nitrogen as to make themodel of femoral head necrosis.Twenty-four rabbits were randomly chosen as theexperimental group and their femoral heads were filled with TCP/PRP. The other 24 rabbits were used as the control group and their femoral heads were filled only with TCP. They were sacrificed at 2, 4,8,12 weeks after operation. The specimens were examined with X-ray and histological study.Results At 2 weeks after operation,there was no significant difference in femoral headdensity between the two groups. Four weeks after operation, femoral head density decreased in both groups, while it decreased more in the control group. At 8,12 weeks after operation, the density of the femoral heads in both groups increased, and it was higher in the experimental group. Histology examination showed thatthere was no difference between the two groups 2 weeks after operation. The head became flat at 4 weeks. Control group had more defects. At 4,8,12 weeks, more repairs were observed in the experimental group than that in the control group. The amount and maturity of osteogenesis in experimental group were much more greaterthan those in control group．Bone histomorphometry showed that the volum of thetrabecular was larger in the experimental group (36.65%±7.22%,38.29%±4.28%，39.24%±3.42%) than that of control group(P＜0.05). Conclusion TCP/PRP does not only provide osteoblasts scaffold, butalso promotes bone formation and the head repair. TCP/PRP is a good biomaterialfor the treatment of femur head necrosis.
Objective To examine an effect of the locally-used platelet derived growth factor-BB (PDGF-BB) on the healing of the medial collateral ligament (MCL) in the knee joints of rats. Methods Forty-eight rats were equally randomly divided into 2 groups: the experimental group (group A) and the control group(group B). MCL of all the rats were ruptured to establish the wound models. In group A, 5 μg of PDGF-BB was locally injected in the wound of each rat and then the wound was sutured; but in group B, the wound was only sutured. After 2 weeks, histological evaluations were performed to determine whether PDGF-BB could promote the healing of MCL. Results There were significantly more fibroblasts formed during the ligament healing process in group A than in group B (213.44±15.32 vs. 180.42±12.78, Plt;0.01). The fibroblasts were more mature andmore regularlyarranged in group A than in group B. The type, content, and crosslink of the collagen were improved to a greater extent in group A than in group B (Plt;0.01). Conclusion PDGF can promote the healing of the injured ligament.
ObjectiveTo study the short-and long-term outcomes of high platelet count in patients with colorectal cancer after surgery. MethodsA total of 398 patients with colorectal cancer who complied with the requirements for this study and operated in professional group on colorectal surgery of Gastrointestinal Surgery Center of West China Hospital in Sichuan University from January 2009 to October 2009 were retrospectively included in this study. Based on the last preoperative platelet count, these patients were divided into normal platelet group(100×109/L-300×109/L)and high platelet group( > 300×109/L). The short-and long-term outcomes were analyzed and compared between two groups. Results①The gender, age, histological type, degree of differentiation, diameter of tumor, site of tumor, and operation method had no significant differences between two groups(P > 0.05), but the ratio ofⅢ, Ⅳstages of TNM in the high platelet group was significantly higher than that in the normal platelet group(P < 0.05).②The first exhaust time and defecation time of the normal platelet group was significantly shorter than those of the high platelet group(P < 0.05). The time of the first oral intake, the time of pull out the drainage, ureter, and nasogastric tube, the time of the first ambulation, and hospitalstay had no significant differences between two groups(P > 0.05).③The total complications rate and single complication rate had no significant differences between two groups(P > 0.05).④All the patients were followed-up with average following-up time 58 months, there were 7 patients with recurrence and 35 patients with death in all the followed-up patients, the recurrence rate and death rate in the high platelet group were significantly higher than those in the normal platelet group(3.5% versus 1.1%, P=0.013; 15.7% versus 6.0%, P=0.002). ConclusionsThere is a relationship of platelet count to colorectal malignant degree. The recovery time of gastrointestinal function is longer, and the local recurrence rate and the postoperative death rate are higher for the patients with high platelet count.
ObjectiveTo explore the clinical efficacy of the ultrasound-guided intra-articular injection of platelet-rich plasma (PRP) in the treatment of patients with different stages of knee osteoarthritis.MethodsWe retrospectively analyzed the clinical characteristics and X-ray data of patients with knee osteoarthritis who received ultrasound-guided intra-articular injection of PRP in the Department of Rehabilitation Medicine at Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University between May 2018 and June 2019. The patients were grouped according to the Kellgren & Lawrence Classification (K&L 0, Ⅰ, Ⅱ, Ⅲ, and Ⅳ). All the patients received four injections with a one-week interval. The Visual Analogue Scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were used to evaluate the clinical efficacy before the injection, and 3 and 6 months after the injection. Adverse reactions were recorded.ResultsA total of 102 patients were included without any grade 0 cases. There were 20 patients in K&L Ⅰ group, 37 in Ⅱ group, 31 in Ⅲ group, and 14 in Ⅳ group. No adverse event was reported. Significant differences of VAS scores and WOMAC index were observed in Ⅰ, Ⅱ and Ⅲ groups at the 3rd and 6th month follow-up (P<0.05). VAS and WOMAC scores of the three groups at the 3rd and 6th month after the treatment were significantly improved compared with those before the treatment (P<0.05). There was no significant difference in VAS score at the 3rd or 6th month after the treatment three groups (P>0.05). For K&L Ⅰ group, there was no statistically significant difference in WOMAC score at the 3rd or 6th month after the treatment (P>0.05). However, the WOMAC scores at the 3rd month after the treatment were better than those at the 6th month in K&L Ⅱ and Ⅲ groups (P<0.05). There was no significant time-depended changes in VAS score or WOMAC score in K&L Ⅳ group (P>0.05).ConclusionThe ultrasound-guided intra-articular PRP injection is safe and effective for pain relief and function improvement in patients with knee osteoarthritis at the early and middle stage.
Objective To investigate the effects of platelet-derived growth factor(PDGF) on the expression of α-smooth muscle actin(α-SMA) of cultured human retinal pigment epithelium cells(RPE). Methods Cultured human RPE cells of the 4-6 th passages were divided into two groups: Delbecco′s modified Eagle′s medium (DMEM) and 2%DMEM (20 g/L foeta calf serum+DMEM). PDGF (0,1,50 ng/ml) was added to medium.The expression of α-SMA was detected and quantitatively analyzed by image process of immunofluorescence.Results PDGF stimulated the expression of α-SMA of human RPE cells.In group of DMEM, The rate of RPE of α-SMA expression was 40%-50% and the intension of fluorescence was 8.08 without PDGF. After stimulated by PDGF(1 ng/ml,50 ng/ml), the rates were 80% and 90% respectively, and the intension of fluorescence were 12.35 and 17.23. In 2%DMEM group, The rates of RPE of α-SMA expression were 85% without PDGF, and 95% ,100% respectively treated with PDGF (1 ng/ml,50 ng/ml). The intension of fluorescence was 14.79 without PDGF, and after stimulated by PDGF, they were 16.28 at 1 ng/ml and 21.36 at 50 ng/ml，which was 2 .7 times ber than that in DMEM group without PDGF. Conclusion PDGF could stimulate RPE cells to express α-SMA. (Chin J Ocul Fundus Dis，2003，19：201-268)
OBJECTIVE The effect of platelet-derived wound healing factor (PDWHF) on wound healing in diabetic rats was studied. METHODS Forty-four male SD rats were randomly divided into 2 groups. Thirty-two rats of experimental group accepted intraperitoneal injection of alloxan (1.5 mg/10 g body weight). Within one or two days after injection, while the blood sugar of the rats was higher than 180 mg/dl, the animal model of diabetic rat should have been established. Then a dorsal incision was given to every rat. After the addition of PDWHF (the experimental group) or bovine albumin (the control group), the incision was sutured up. Seven, ten and fourteen days after operation, the breaking strength of the wound was measured. On another hand, specimen from the wound was taken for the culture of fibroblasts. When the cultured fibroblasts have been incubated with 10% PDWHF for 4, 8 and 12 hours, the procollagen I (alpha 1) mRNA levels were examined respectively, and compared with those of control. RESULTS Significant difference in wound breaking strength had been observed between PDWHF-treated incisions and the control on 7, 10 and 14 days after wounding (P lt; 0.01). Experiment in vitro demonstrated that the procollagen I (alpha 1) mRNA levels in wound fibroblasts incubated with 10% PDWHF for 4, 8 and 12 hours were 0.9, 3.7 and 2.2 folds higher than those in fibroblasts in control. CONCLUSION It was suggested that direct stimulation of procollagen I (alpha 1) gene expression was one of the ways that PDWHF played its role in accelerating wound healing.
Objective To study the effect of platelet-rich plasma (PRP) on repairing chronic wounds of lower l imbs. Methods From May 2007 to November 2007, 47 patients suffering from chronic wounds of lower l imbs were treated. There were 41 males and 6 females, aged from 15 to 68 years (43.2 years on average). The disease was caused by tibiofibulafracture in 20 cases, calcaneus fracture in 4 cases, metatarsal fracture in 1 case, multiple open fracture of lower l imbs in 3 cases, tibia osteomyel itis in 10 cases, femur osteomyel itis in 1 case, soft tissue injury of ankle in 4 cases, infection after amputation in 2 cases, infection after foot orthomorphia in 1 case, and infection after calcaneus tendon neoplasty in 1 case. Their chronic wounds did not healed after 2 to 4 months of therapy. Among them, chronic wounds compl icated with fracture nonunion in 23 cases and positive bacterial culture result in 38 cases. Debridement and autogenous PRP gel injection were appl ied every 2 months and for twice. Results The patients were followed up for 4 months after the first PRP injection. Two months after the first PRP injection, chronic wounds contracted significantly in 34 patients with purulence and necrosis tissue cleaned up, circulation of soft tissue improved and exposed bone or muscle tissue covered by neogenetic granulation. No patient was completely cured. Two months after the second PRP injection, the average coverage rate was 79.3% ± 18.0%, the total cure rate was 29.8%. The volume of the chronic wounds decreased by (9.3 ± 4.9) mL after PRP therapy (2.5 ± 2.7) mL when compared with (11.8 ± 5.6) mL of before therapy, showing significant difference (P lt; 0.05). X-ray photograph showed that among the 23 cases of fracture nonunion, fracture healed completely in 9 cases; bony callus formation increased obviously in 12 cases; no significant change was observed in 2 cases. No aggravated sign of osteomyel itis was notified. Positive results of bacterial culture reduced to 15 cases. Conclusion PRP efficiently enhances the recovery of soft tissue defect and speeds up the chronic wounds heal ing oflower l imbs.
ObjectiveTo investigate the changes of platelet-leukocyte aggregates (PLA) level in patients with sepsis and its diagnostic value in sepsis complicated with acute respiratory distress syndrome (ARDS).MethodsA prospective study was carried in adult sepsis patients admitted to our hospital from January 2015 to November 2016. According to the 2012 " Berlin definition” diagnostic criteria, 58 cases of sepsis with ARDS were allocated to an experimental group and 139 cases of sepsis non-ARDS patients were allocated to a control group. Immediately after the diagnosis of sepsis, elbow vein blood samples were collected for flow cytometry assay of PLA. The acute physiology and chronic health assessment II (APACHE II score) of each group was performed and the receiver operating characteristic (ROC) curve was drawn.ResultsPlatelet-neutrophil aggregates (PNA) and platelet-lymphocyte aggregates (PLyA) in the experimental group were higher than those in the control group, but there were no significant differences (both P>0.05). The platelet-monocyte aggregates (PMA) of the experimental group was significantly higher than that of the control group (P<0.05). Peripheral blood PMA was positively correlated with APACHE II score (r=0.671, P<0.001). When PMA was used as the test variable, the area under the curve (AUC) was 0.945 with significant diagnostic value (P<0.001), and optimal cutoff value of PMA was 8.25%, with diagnostic sensitivity of 0.806 and diagnostic specificity of 0.951. When APACHE II was used as the test variable, AUC was 0.930, with significant diagnostic value (P<0.001), and optimal threshold of APACHE II was 16.500 with diagnostic sensitivity of 0.871 and diagnostic specificity of 0.852.ConclusionPMA is of great value in the diagnosis of sepsis with ARDS.
Objective Platelet-rich plasma (PRP) can promote wound heal ing. To observe the effect of PRP injection on the early heal ing of rat’s Achilles tendon rupture so as to provide the experimental basis for cl inical practice. Methods Forty-six Sprague Dawley rats were included in this experiment, female or male and weighing 190-240 g. PRP and platelet-poor plasma (PPP) were prepared from the heart arterial blood of 10 rats; other 36 rats were made the models of Achilles tendon rupture, and were randomly divided into 3 groups (control group, PPP group, and PRP group), 12 rats for each group. In PPP and PRP groups, PPP and PRP of 100 μL were injected around the tendons once a week, respectively; in the control group, nothing was injected. The tendon tissue sample was harvested at 1, 2, 3, and 4 weeks after operation for morphology, histology, and immunohistochemistry observations. The content of collagen type I fibers also was measured. Specimens of each group were obtained for biomechanical test at 4 weeks. Results All the animals survived till the end of the experiment. Tendon edema gradually decreased and sliding improved with time. The tendon adhesion increased steadily from 1 week to 3 weeks postoperatively, and it was relieved at 4 weeks in 3 groups. There was no significant ifference in the grading of tendon adhesion among 3 groups at 1 week and at 4 weeks (P gt; 0.05), respectively. The inflammatory cell infiltration, angiogenesis, and collagen fibers were more in PRP group than in PPP group and control group at 1 week; with time, inflammatory cell infiltration and angiogenesis gradually decreased. Positive staining of collagen type I fibers was observed at 1-4 weeks postoperatively in 3 groups. The positive density of collagen type I fibers in group PRP was significantly higher than that in control group and PPP group at 1, 2, and 3 weeks (P lt; 0.05), but no significant difference was found among 3 groups at 4 weeks (P gt; 0.05). The biomechanical tests showed that there was no significant difference in the maximal gl iding excursion among 3 groups at 4 weeks postoperatively (P gt; 0.05); the elasticity modulus and the ultimate tensile strength of PRP group were significantly higher than those of control group and PPP group at 4 weeks (P lt; 0.05). Conclusion PRP injection can improve the healing of Achilles tendon in early repair of rat’s Achilles tendon rupture.