Preparation and preliminary evaluation of sodium alginate/agarose/carboxymethyl chitosan spray film dressing carrying platelet rich plasma for wound repair / 中国输血杂志

【Objective】 To develop a spray-on membrane dressing for wound repair containing platelet rich plasma (PRP) sodium alginate (SA)/agarose(AG)/carboxymethyl chitosan (CMCS). 【Methods】 SA/AG/ CMCS were mixed in different proportions to prepare biodegradable quick setting spray (BQSS) by blending film method, and the film-forming time, moisture retention and compression resistance of the prepared BQSS were tested. Then PRP and BQSS were mixed in the proportion of 3∶7, 4∶6, 5∶5, 6∶4 and 7∶3 to prepare PRP-BQSS spray film dressings. The film-forming time, moisture retention, compressive strength, porosity and slow-release effect of growth factors of PRP-BQSS spray film dressings were studied. 【Results】 In the preparation of BQSS compound spray film solution, when SA, AG, CMCS and sterile distilled water were 0.6∶0.6∶0.6∶98.2g, the film-forming time (7.73±0.31) s, moisture retention (75. 54±3.03) % and compression resistance (791.00±68.02) g of the spray-film dressing were the best. The basic properties of PRP-BQSS spray-on film dressings and the release of growth factors show that PRP-BQSS spray-on film dressings can exist in different forms, and with the decrease of PRP concentration percentage, its film-forming time, moisturizing performance and compressive strength showed an upward trend. When the PRP content is 30%, the porosity of the dressing is the highest, about(84.34±0.90)%. The release of platelet-derived growth factor-AA(PDGF-AA), platelet factor-4(PF-4) and transforming growth factor beta (TGF-β) was in a slow upward trend, and the release of the three growth factors was higher than that of PRP group in 48 hours. 【Conclusion】 The preparation method of PRP-BQSS spray film dressing designed in this study is simple and mild, and can form a film quickly, with good biological properties and better growth factor inhibition and sustained-release effect.

Comparison of effects of different anticoagulants on the release of growth factor and injection pain of platelet-rich plasma in SD rats / 中国输血杂志

【Objective】 To investigate the effects of different anticoagulants on platelet-rich plasma(PRP) release content of growth factor and injection pain. 【Methods】 A total of 15 voluntary blood donors were selected, with each blood donor using four kinds of anticoagulant tubes with EDTA-K2 anticoagulation, EDTA-NA2 anticoagulation, citrate anticoagulation, ACD-A anticoagulation respectively as group A, B, C and D. PRP was isolated and prepared by the rich plasma method, and the contents of PDGF-AA, TGF-β, IGF-1, VEGF, and PF-4 were detected by enzyme-linked immunosorbent assay. Meanwhile, SD rats (20, 4 / group) were injected subcutaneously or intradermally with the supernatant of PRP and PG gel prepared in the 4 groups and normal saline in the control group. The pain status of SD rats during the injection was observed and recorded. The pain status of the 5 groups of experimental animals was evaluated according to the American Laboratory Animal Pain Guide. 【Results】 The platelet counts in PRP in group D was the highest [(1 294.53±277.37) × 109/L], which was significantly higher than that in group A [ (789.13±377.13) ×109/L] and group C [ (990.94±493.12) ×109/L] (P<0.05). The OD value of PDGF-AA in group A, B, C, and D were 1.51± 0.18, 1.69±0.21, 0.66±0.19and 1.72±0.13, respectively, with statistically significant difference between groups (P<0.05 ) and group D better than the other three groups. The OD value of PF-4 was 1.18±0.24, 1.61±0.14, 0.65±0.26 and 1.72±0.10 respectively, with statistically significant difference between groups (P<0.05) and group D better than other three groups. The OD value of IGF-1 was 1.02±0.08, 0.98±0.11, 1.06±0.11 and 1.32±0.65 respectively, with no significant difference between groups (P>0.05). The OD value of VEGF was 0.13±0.04, 0.21±0.14, 0.08±0.02 and 0.13±0.04 respectively, with statistically significant difference between group B and C (P<0.05). The OD value of TGF-β was 0.14±0.01, 0.15±0.01, 0.28±0.17 and 1.10±0.37 respectively, with statistically significant difference between groups (P<0.05) and group D better than other three groups. Comparison of injection pain: when the supernatant of PRP and PG gel was injected, there were significant differences between group A, B, C and D, and the control group (P<0.05) . The median pain scores of PRP injection of group A, B, C, and D were 6 (1.5), 5 (0.75), 4.5 (2.5), and 3(3) respectively, with group D lower than other three groups, and no statistically significant difference was noticed (P>0.05) . The median pain scores of the PG supernatant injection of group A, B, C, and D were 4 (2.25), 3 (2.75), 4 (3), 1 (1.5), and the difference was not statistically significant (P>0.05). There was no significant difference between the PRP injection group and the PG supernatant group (P> 0.05). 【Conclusion】 PRP prepared by two-step centrifugation with ACD-A anticoagulant can obtain the higher platelet counts and the maximum release of PDGF-AA, PF-4, IGF-1, and TGF-β. In terms of pain, ACD-A anticoagulant injection has the lowest pain with the animals.

Application of autologous platelet-rich plasma in the treatment of postoperative bone nonunion for long bone shaft fractures during and after operation / 中国输血杂志

【Objective】 To explore the clinical effects of autologous platelet-rich plasma (PRP) in the treatment of postoperative bone nonunion for long bone shaft fractures during operation and after operation. 【Methods】 A total of 34 patients with postoperative bone nonunion for long bone shaft fracture, who were admitted and cured in the Orthopedics Department of our hospital from January 2019 to June 2020, were selected. They were randomly divided into the experimental group(n=17) and control group(n=17). Individuals in the control were treated with autologous iliac bone alone., while the experimental group were treated with autologous iliac bone graft plus autologous PRP during and after operation. After surgery, the autogenous PRP was accurately injected with ultrasound guidance every 7 days (5 mL/person, 4 occasions in total). The clinical healing time of the fracture, the grading of callus formation and the functional rehabilitation level of limbs on the affected side at different time were observed in both groups. 【Results】 All 34 patients were followed up. In the experimental group and the control group, the clinical healing time (month) of the fracture was (5.03±1.24) vs (6.91±1.41), P<0.05. The healing rate of the fracture for 6 months and 9 months was 94%(16/17)vs 59%(10/17)and 94%(16/17)vs 82%(14/17), respectively (P<0.05). The grading of callus formation within 3, 6 and 9 months was (2.11±0.69) vs (1.53±0.80), (3.06±0.90) vs (2.59±0.87) and (3.82±0.73) vs (3.35±0.86), respectively (P<0.05). The acceptance rate of functional rehabilitation of limbs on the affected side was 82.35%(14/17)vs 76.47%(13/17), P<0.05. 【Conclusion】 The application of autologous PRP in the treatment of postoperative bone nonunion for long bone shaft fractures during operation and after operation can achieve good clinical treatment.

Study on the repair effect of lyophilized platelet lysate products on articular cartilage injury model of rat / 中国输血杂志

【Objective】 To discuss the repair effect of lyophilized platelet lysate (PL) products on articular cartilage injury model of rats. 【Methods】 A total of 25 SD rats were injected with typeⅡcollagenase at the right knuckle articular cavity respectively on day 1, 3 and 5 of experiment, and the modeling conditions were observed 14 days after the last injection of collagenase. The SD rats with successful modeling were randomly divided into three groups, and were injected with lyophilized PL [Group A, 1 mL/(mouse·time)], PL [Group B, 1 mL/(mouse·time)], and normal saline[Group C, 1 mL/(mouse·time)]. The above three substances were injected with corresponding drugs on day 0, 7, 14 and 21 of experiment based on the grouping conditions, and the changes of knee joint diameters of the rats from the three groups were observed and compared. On day 14 and 28, one rat in each group was randomly killed and two knuckle articular cavities of each were taken for tissue sampling, using hematoxylin-eosin staining (HE) and immunohistochemistry. 【Results】 After 14 days of modeling by injection of type Ⅱ collagenase, the proportion of successful modeling in rats was 84% (21/25), with the knee joint diameter (mm) before and after modeling at 12.84±1.14 vs 14.11±1.17(P<0.01). On day 14, 21 and 28, groups A and B were superior to group C in the knee joint diameter and activity improvement (P<0.05), with 13.33±1.16 vs 13.37±1.08 vs 14.21±1.08, 13.10±1.09 vs 13.01±1.04 vs 14.09±1.09 and 12.38±1.08 vs 12.51±1.03 vs 14.01±1.07, respectively. Histological observation showed that group A and B were superior to group C in the production and arrangement of chondrocytes and the positive expression of type Ⅱ collagen, and there was no significant difference between group A and group B. 【Conclusion】 The lyophilized PL has similar therapeutic effect to PL in the treatment and repair of articular cartilage injury, and is worthy of clinical application.

Influencing factors of clinical efficacy of autologous platelet-rich plasma in the treatment of androgenetic alopecia / 中国输血杂志

【Objective】 To analyze the influencing factors of clinical efficacy of autologous platelet-rich plasma in the treatment of androgenetic alopecia. 【Methods】 From January, 2019 to December, 2021, 151 outpatients with androgenetic alopecia were treated in our hospital. All patients were treated with autologous PRP injection once a month and planned to received injection for 4-6 occasions. According to the hair growth before and after treatment, the treatment results were evaluated. The influencing factors in the treatment results were grouped and analyzed, including the treatment numbers (divided into 1-6 occasions), the grade of alopecia(three grades: mild, moderate and severe alopecia) and the Plt concentration in PRP[five grades(×109/L): extremely low concentration (<800), low concentration (801-1 000) and medium concentration (1 001-1 200), high concentration(1 201-1 500)and extremely high concentration(>1 501)]. 【Results】 The correlation coefficient between the number of treatments and the effective rate was pearson=0.986, P<0.001, showing a positive correlation. There was a statistical difference in the total number of treatments between groups (P<0.01). As to the severity of alopecia: The effective rates of mild and moderate alopecia patients (66.67%, 56.95%) were higher than those of severe alopecia patients (35%). The difference between groups was statistically significant (P<0.01). As to the concentration of Plt in PRP: The concentration of Plt directly affected the therapeutic effect. When the Plt count was (1 200-1 500)×109/L, the effect was optimal, reaching 68.12%, which was significantly higher than the other four groups(P<0.01). The treatment numbers, alopecia grade and Plt concentration in PRP were all related to the effectiveness of treatment (P<0.05). When the OR value of treatment numbers and Plt concentration was >1, the effective rate increased by 2.619 times and 2.033 times, respectively, as treatment numbers and Plt concentration increased. When the OR value of the grade of alopecia was 0.338 (0<0.338<1), the effective rate decreased with the increase of alopecia severity; For each grade increased, the effective rate would be compromised by 0.338. 【Conclusion】 When PRP is applied to treat AGA patients, the clinical therapeutic effect will be better in patients who received more treatments, PRP with higher Plt count, and be in the early degree of hair loss. Whether the higher the concentration of Plt in PRP, the better the therapeutic effect will be, remains to be further verified.

Effect of temperature on the preparation of platelet-rich plasma / 中国输血杂志

【Objective】 To discuss the effect of temperature on the quality of platelet-rich plasma (PRP) prepared manually. 【Methods】 A total of 120 peripheral blood samples (60 mL/ person) were collected from healthy voluntary blood donors in the Blood Center of General Hospital of Southern Theater Command from May 10, 2010 to September 10, 2010. Each whole blood sample (60mL/ person) was randomly divided into 3 aliquots(20 mL each), totaling 360 aliquots, then divided into 9 groups (A1, A2, A3, B1, B2, B3, C1, C2, and C3), with 40 aliquots in each group. In group A: the ambient temperature for PRP preparation was set to (4±2)℃, and the temperature for PRP preparation and centrifugal bin was (4±2)℃, (24±2)℃ and (30±2)℃ for group A1, A2, and A3, respectively. In group B: the ambient temperature for PRP preparation was set to (24±2)℃, and the temperature for PRP preparation and centrifugal bin was (4±2)℃, (24±2)℃ and (30±2)℃ for group B1, B2 and B3 respectively. In group C: the ambient temperature for PRP preparation was set to (30±2)℃, and the temperature for PRP preparation and centrifugal bin was (4±2)℃, (24±2)℃ and (30±2)℃ for group C1, C2 and C3 respectively. Platelet concentrates were separated and prepared by rich slurry method, and the platelet recovery rate was calculated for each group, the platelet morphology was observed under the microscope, and the concentrations of platelet-derived growth factor (PDGF-BB), transforming growth factor β (TGF-β) and vascular endothelial growth factor (VEGF) were quantitatively determined using enzyme-linked immunosorbent assay (ELISA). 【Results】 The platelet count and platelet recovery rate were compared as follows: among group A1, A2, A3, B1, B2, B3, C1, C2 and C3, the results of A3, B3 and C3were (489.2±21.47) × 109/L vs (495.7±23.2) ×109/L vs (489.4±17.1) ×109/L and (57.4±2.3)% vs (54.9±1.3)% vs (50.7±2.3)%, respectively, all showed platelet aggregation, and the differences, relative to A1 and A2, B1 and B2, and C1 and C2, were statistically significant (P<0.05). Microscopic observation was as follows: in the PRPs collected from group A1, A2, B1, B2, C1 and C2, the platelet cells were uniform in size and without aggregation; in the PRPs collected from group A3, B3 and C3, some platelets showed aggregation. Determination of growth factor content was as follows: the content of TGF-β(ng/L) and PDGF-BB(ng/L) was 375.0±119.1 vs 183.67±106.2 and 933.0±273.0 vs 656±113.0 in the non-aggregation group and the aggregation group, respectively (P<0.05), while the content of VEGF(ng/L) was 217.5±93.5 vs 155.3±103.4 (P>0.05), with no statistically difference. 【Conclusion】 The ambient temperature had little effect on the preparation of PRP, and the temperature of the centrifuge bin was better to be maintained at (24±2)℃.