Therapeutic Effectiveness of Leukocyte-and Platelet-rich Fibrin for Diabetic Foot Ulcers:A Retrospective Study

Objective Diabetic foot ulcer(DFU)is one of the most serious complications of diabetes.Leukocyte-and platelet-rich fibrin(L-PRF)is a second-generation autologous platelet-rich plasma.This study aims to investigate the clinical effects of L-PRF in patients with diabetes in real clinical practice.Methods Patients with DFU who received L-PRF treatment and standard of care(SOC)from 2018 to 2019 in Tongji Hospital were enrolled.The clinical information including patient characteristics,wound evaluation(area,severity,infection,blood supply),SOC of DFU,and images of ulcers was retrospectively extracted and analyzed.L-PRF treatment was performed every 7±2 days until the ulcer exhibited complete epithelialization or an overall percent volume reduction(PVR)greater than 80%.Therapeutic effectiveness,including overall PVR and the overall and weekly healing rates,was evaluated.Results Totally,26 patients with DFU were enrolled,and they had an ulcer duration of 47.0(35.0,72.3)days.The severity and infection of ulcers varied,as indicated by the Site,Ischemia,Neuropathy,Bacterial Infection,and Depth(SINBAD)scores of 2–6,Wagner grades of 1–4,and the Perfusion,Extent,Depth,Infection and Sensation(PEDIS)scores of 2–4.The initial ulcer volume before L-PRF treatment was 4.94(1.50,13.83)cm3,and the final ulcer volume was 0.35(0.03,1.76)cm3.The median number of L-PRF doses was 3(2,5).A total of 11 patients achieved complete epithelialization after the fifth week of treatment,and 19 patients achieved at least an 80%volume reduction after the seventh week.The overall wound-healing rate was 1.47(0.63,3.29)cm3/week,and the healing rate was faster in the first 2 weeks than in the remaining weeks.Concurrent treatment did not change the percentage of complete epithelialization or healing rate.Conclusion Adding L-PRF to SOC significantly improved wound healing in patients with DFU independent of the ankle brachial index,SINBAD score,or Wagner grade,indicating that this method is appropriate for DFU treatment under different clinical conditions.

Rescuing“hopeless”avulsed teeth using autologous platelet-rich fibrin following delayed reimplantation:Two case reports

BACKGROUND Tooth avulsion is one of the most severe types of dental trauma.Most avulsed teeth undergo long-term ankylosis and replacement resorption after delayed reimplantation and exhibit a poor prognosis.The aim of this work was to improve the success rate of avulsed teeth after delayed reimplantation using autologous platelet-rich fibrin(PRF).CASE SUMMARY Case 1 was a 14-year-old boy who fell and knocked out his left upper central incisor 18 h prior to his arrival at the department.The diagnoses were avulsion of tooth 21,lateral luxation of tooth 11 and alveolar fracture of teeth 11 and 21.In case 2,a 17-year-old boy fell 2 h prior to his presentation to the hospital,and his left upper lateral incisor was completely knocked out of the alveolar socket.The diagnoses included avulsion of tooth 22,complicated crown fracture of tooth 11and complicated crown-root fracture of tooth 21.The avulsed teeth were reimplanted along with autologous PRF granules and splinted using a semiflexible titanium preshaped labial arch.The root canals of the avulsed teeth were filled with calcium hydroxide paste,and root canal filling was performed 4 wk after reimplantation.The reimplanted teeth showed no symptoms of inflammatory root resorption or ankylosis at the 3-,6-,and 12-mo follow-up examinations after reimplantation with autologous PRF.In addition to the avulsed teeth,the other injured teeth were treated using corresponding conventional treatment methods.CONCLUSION These cases provide examples of the successful use of PRF to reduce pathological root resorption of the avulsed teeth,and the application of PRF may provide new healing opportunities for traditionally“hopeless”avulsed teeth.

Platelet-rich fibrin-induced bone marrow mesenchymal stem cell differentiation into osteoblast-like cells and neural cells

Bone marrow mesenchymal stem cells were allowed to develop for 14 days in a platelet-rich fibrin environment.Results demonstrated that platelet-rich fibrin significantly promoted bone marrow mesenchymal stem cell proliferation.In addition,there was a dose-dependent increase in Runt-related transcription factor-2 and bone morphogenetic protein-2 mRNA expression,as well as neuron-specific enolase and glial acidic protein.Results showed that platelet-rich fibrin promoted bone marrow mesenchymal stem cell proliferation and differentiation of osteoblast-like cells and neural cells in a dose-dependent manner.

Periodontally accelerated osteogenic orthodontics with platelet-rich fibrin in an adult patient with periodontal disease:A case report and review of literature

BACKGROUND In the clinical scenario,adult patients with periodontal diseases and dental malformation,characterized by dental crowding in lower anterior teeth with the thin biotype,often require orthodontic treatment.This case report aimed to evaluate the clinical and radiographic outcomes of periodontally accelerated osteogenic orthodontics(PAOO)combined with autologous platelet-rich fibrin(PRF)in an adult patient with class I malocclusion along with dental crowding,a thin periodontal biotype,and buccal plate deficiency.CASE SUMMARY A 32-year-old female complaining of dental crowding and gingival bleeding was referred to the orthodontic clinic.The patient underwent periodontal risk assessment prior to orthodontic treatment.She was diagnosed with a high risk of gingival recession due to dental crowding,root prominence,loss of buccal plates,and a thin gingival tissue biotype.The treatment regimen included PAOO combined with autologous PRF for alveolar augmentation and interproximal enamel reduction for moderate dental crowding.Clinically,PAOO-assisted orthodontic tooth movement in this case showed enhanced periodontium remodeling.Radiographic outcomes also showed statistically significant improvements(P<0.01)in the mandibular buccal alveolar bone.CONCLUSION This case report suggests the combination of autologous PRF with PAOO to enhance bone augmentation and long-term tissue support in adult orthodontic patients with periodontal disease.

Peri-implant keratinized gingiva augmentation using xenogeneic collagen matrix and platelet-rich fibrin:A case report

BACKGROUND Keratinized gingival insufficiency is a disease attributed to long-term tooth loss,can severely jeopardizes the long-term health of implants.A simple and effective augmentation surgery method should be urgently developed.CASE SUMMARY A healthy female patient,45-year-old,requested implant restoration of the her left mandibular first molar and second molar.Before considering a stage II,as suggested from the probing depth measurements,the widths of the mesial,medial,and distal buccal keratinized gingiva of second molar(tooth#37)were measured and found to be 0.5 mm,0.5 mm,and 0 mm,respectively.This suggested that the gingiva was insufficient to resist damage from bacterial and mechanical stimulation.Accordingly,modified apically repositioned flap(ARF)surgery combined with xenogeneic collagen matrix(XCM)and platelet-rich fibrin(PRF)was employed to increase the width of gingival tissue.After 1 mo of healing,the widths of mesial,medial,and distal buccal keratinized gingiva reached 4 mm,4 mm,and 3 mm,respectively,and the thickness of the augmented mucosa was 4.5 mm.Subsequently,through the second-stage operation,the patient obtained an ideal soft tissue shape around the implant.CONCLUSION For cases with keratinized gingiva widths around implants less than 2mm􀀀the soft tissue width and thickness could be increased by modified ARF surgery combined with XCM and PRF.Moreover,this surgery significantly alleviated patients’pain and ameliorated oral functional comfort.

Flapless immediate implant placement into fresh molar extraction socket using platelet-rich fibrin: A case report

BACKGROUND There are some challenges concerning immediate implant placement in the molar region.Platelet-rich fibrin(PRF),an autologous biomaterial,has been used widely for periodontal intra-bony defects,sinus augmentation,socket preservation,and gingival recession.However,the literature remains scarce for reports on immediate implants with PRF,particularly in the case of fresh molar extraction socket.CASE SUMMARY The patient was a 43-year-old woman with maxillary molar vertical crown-root fracture.She underwent flapless immediate implant placement into the fresh molar socket with PRF.At the follow-up visit 15 d post procedure,the vascularization of soft tissue was visible.There was no swelling or pain after the surgery.Six months postoperatively,the regeneration of bone and soft tissues was visible.Subsequently,the definitive restoration was placed.The patient was satisfied with the aesthetic outcomes.CONCLUSION The flapless immediate implant placement into the fresh molar socket with PRF is a feasible procedure.This case report demonstrates that PRF promotes bone and soft tissue regeneration apart from having an enhanced anti-inflammatory ability.Furthermore,the procedure involves a minimally invasive technique,thus reducing the surgical complexity.

Early therapeutic effect of platelet-rich fibrin combined with allogeneic bone marrow-derived stem cells on rats’ critical-sized mandibular defects

BACKGROUND Critically sized bone defects represent a significant challenge to orthopaedic surgeons worldwide.These defects generally result from severe trauma or resection of a whole large tumour.Autologous bone grafts are the current gold standard for the reconstruction of such defects.However,due to increased patient morbidity and the need for a second operative site,other lines of treatment should be introduced.To find alternative unconventional therapies to manage such defects,bone tissue engineering using a combination of suitable bioactive factors,cells,and biocompatible scaffolds offers a promising new approach for bone regeneration.AIM To evaluate the healing capacity of platelet-rich fibrin(PRF)membranes seeded with allogeneic mesenchymal bone marrow-derived stem cells(BMSCs)on critically sized mandibular defects in a rat model.METHODS Sixty-three Sprague Dawley rats were subjected to bilateral bone defects of critical size in the mandibles created by a 5-mm diameter trephine bur.Rats were allocated to three equal groups of 21 rats each.Group I bone defects were irrigated with normal saline and designed as negative controls.Defects of group II were grafted with PRF membranes and served as positive controls,while defects of group III were grafted with PRF membranes seeded with allogeneic BMSCs.Seven rats from each group were killed at 1,2 and 4 wk.The mandibles were dissected and prepared for routine haematoxylin and eosin(HE)staining,Masson's trichrome staining and CD68 immunohistochemical staining.RESULTS Four weeks postoperatively,the percentage area of newly formed bone was significantly higher in group III(0.88±0.02)than in groups I(0.02±0.00)and II(0.60±0.02).The amount of granulation tissue formation was lower in group III(0.12±0.02)than in groups I(0.20±0.02)and II(0.40±0.02).The number of inflammatory cells was lower in group III(0.29±0.03)than in groups I(4.82±0.08)and II(3.09±0.07).CONCLUSION Bone regenerative quality of critically sized mandibular bone defects in rats was better promoted by PRF membranes seeded with BMSCs than with PRF membranes alone.

Implant site development using titanium plate and platelet-rich fibrin for congenitally missed maxillary lateral incisors:A case report

BACKGROUND Bone deficiency and soft tissue atrophy in the absence of maxillary lateral incisors are among the most challenging problems for implant clinicians.Autologous bone grafting is the gold standard for bone augmentation,but not without limitations.Platelet-rich fibrin(PRF),a biodegradable autologous biomaterial,has been widely used for bone and soft tissue management.Moreover,titanium plate is an advantageous barrier due to its good space-maintaining ability.However,there is a lack of literature on implant site development using titanium plate and PRF for congenitally missing maxillary lateral incisors.CASE SUMMARY The patient was a 19-year-old girl with a congenitally missing tooth(#12).She underwent implant placement and simultaneous autologous bone grafting with titanium plate and PRF.At the follow-up visit 15 d post-procedure,the vascularization of soft tissue was visible.There was no swelling or pain after the surgery.Six months postoperatively,bone regeneration was evident.Subsequently,the definitive restoration was placed,and the patient was satisfied with the esthetic outcomes.CONCLUSION Implant site development using titanium plate and PRF for congenitally missing maxillary lateral incisors is a feasible procedure.In this case,the labial bone plate was displaced but remained connected to the base bone,ensuring blood supply.The titanium plate fixed the labial bone plate and maintained the osteogenic space,while the PRF provided growth factors and leukocytes for bone and soft tissue regeneration.Furthermore,the procedure reduced the surgical complexity and adverse reactions,displaying outstanding esthetic outcomes.

Autologous platelet-rich-fibrin-induced revascularization sequelae:Two case reports Autologous platelet-rich-fibrin-induced revascularization sequelae:Two case reports

BACKGROUND A key requirement for biomimetic regeneration of tissues is a 3D scaffold.The gold standard scaffold for revascularization is the blood clot,however,an adequate blood clot cannot always be achieved in narrow canals or mature roots.Hereby,we document the effects of platelet-rich fibrin(PRF)for the regenerative endodontic treatment(RET)of two immature permanent teeth with necrotic pulps for up to 48 mo.CASES SUMMARY The first patient was a 22-year-old female with history of trauma in tooth#9 with a sinus tract and a large periapical lesion.The second was a 9-year-old male presenting with a badly decayed tooth#14.Both cases were treated with RET and PRF prepared from the patients’blood.PRF and its extract were used as a scaffold for RET.Patients were followed-up to 9 and 48 mo(4 years),respectively.Both patients,were asymptomatic after treatment.At the 9-mo-follow-up of case#1,there was radiographic evidence of periapical bone healing,however,the root apex was still open.In case#2,the roots exhibited apical closure and normal periapical bone architecture at 12-mo follow-up,while no root lengthening was observed.After 48 mo,case#2 showed extensive intracanal calcification in all root canals that complicated conventional root canal treatment.CONCLUSION RET with PRF and its extract could be used in revascularization of immature permanent teeth.However,proper case selection to comply with long-term follow-up is necessary and adverse events such as calcification and canal obliteration should be planned for.

Comparative evaluation of effect of injectable platelet-rich fibrin with collagen membrane compared with collagen membrane alone for gingival recession coverage

BACKGROUND Collagen membrane and platelet-rich fibrin(PRF)have emerged as vital biomaterials in the field of periodontal regeneration.Minimally invasive techniques are being preferred by most periodontists,as it is patient compliant with fewer post-surgical complications as compared to conventional surgical techniques.Thus,in this study we have evaluated the effect of injectable PRF(i-PRF)with collagen membrane compared with collagen membrane alone using vestibular incision subperiosteal tunnel access(VISTA)technique for gingival recession coverage.AIM To compare the efficacy of VISTA using collagen membrane with collagen membrane soaked in injectable PRF for gingival recession coverage.METHODS A split mouth randomized controlled clinical trial was designed;13 subjects having at least 2 teeth indicated for recession coverage were enrolled in this study.The sites were randomly assigned to control group(VISTA using collagen membrane alone)and the test group(VISTA using collagen membrane with i-PRF).The clinical parameters assessed were pocket depth,recession depth(RD),recession width(RW),relative attachment level,keratinised tissue width(KTW),keratinised tissue thickness(KTT),and percentage root coverage.RESULTS RD showed a statistically significant difference between the test group at 3 mo(0.5±0.513)and 6 mo(0.9±0.641)and the control group at 3 mo(0.95±0.51)and 6 mo(1.5±0.571),with P values of 0.008 and 0.04,respectively.RW also showed a statistically significant difference between the test group at 3 mo(1±1.026)and 6 mo(1.65±1.04)and the control group at 3 mo(1.85±0.875)and 6 mo(2.25±0.759),with P values of 0.008 and 0.001,respectively.Results for KTW showed statistically significant results between the test group at 1 mo(2.85±0.489),3 mo(3.5±0.513),and 6 mo(3.4±0.598)and the control group at 1 mo(2.45±0.605),3 mo(2.9±0.447),and 6 mo(2.75±0.444),with P values of 0.04,0.004,and 0.003,respectively.Results for KTT also showed statistically significant results between test group at 1 mo(2.69±0.233),3 mo(2.53±0.212),and 6 mo(2.46±0.252)and the control group at 1 mo(2.12±0.193),3 mo(2.02±0.18),and 6 mo(1.91±0.166),with P values of 0.001,0.001,and 0.001,respectively.The test group showed 91.6%,81.6%,and 67%root coverage at 1 mo,3 mo,and 6 mo,while the control group showed 82.3%,66.4%,and 53.95%of root coverage at 1 mo,3 mo,and 6 mo,respectively.CONCLUSION The use of minimally invasive VISTA technique along with collagen membrane and injectable form of platelet-rich fibrin can be successfully used as a treatment method for multiple or isolated gingival recessions of Miller’s class-I and class-II defects.

Evaluating the Benefits of Platelet Rich-Fibrin in Periodontal Regeneration: A Literature Review

Introduction: Platelet Rich-Fibrin (PRF) is a biological matrix derived from a patient’s own blood, rich in growth factors and platelets. Its use in various periodontal and non-periodontal procedures is gaining recognition due to its potential in promoting tissue regeneration. The purpose of this review was to evaluate the benefits of using PRF in intra-bony defect regeneration, guided-bone regeneration, and sinus floor elevation. Methods: The study searched PubMed for manuscripts published between 2017 and 2022 to better understand the clinical and radiological effects of PRF. The manuscripts were divided into the following sections: intra-bony defect regeneration, guided-bone regeneration, and sinus floor elevation. Results: In intra-bony defects, PRF improved clinical and radiological parameters when compared with OFD alone, with a significant difference in wound healing at 7 days. In GBR, a CBCT evaluation shows no statistical difference between the PRF-autogenous bone complex group and the bovine bone-collagen membrane complex regarding volume change of the augmented bone with a 16% rate of bone loss following a 6-month healing period. Also, a slight increase in bone thickness has been seen when liquid PRF is used. In sinus floor elevation, results revealed no differences in graft volume between PRF group and control group at any of the evaluated time points. Although higher implant stability immediately postoperatively, higher new bone formation, the lesser amount of residual graft and earlier implant placement. Conclusion: Platelet Rich-Fibrin is widely accepted for use in periodontal surgery and dentistry due to its minimally invasive nature and low risk of adverse effects, with positive results in tissue regeneration. There is evidence that PRF leads to improved and faster healing, as well as cost-effective regenerative procedures compared to other treatments.

WHBE兔膝骨关节炎模型的建立与PRFr的干预研究

目的采用内侧副韧带和部分髌韧带切除术建立WHBE兔KOA模型并用富血小板纤维蛋白释放液(PRFr)干预,探讨WHBE兔KOA模型软骨损伤和炎症的机制以及PRFr干预疗效。方法取WHBE兔24只,随机分成3组,即对照(NC)组(n=6)、模型(KOA)组(n=12)和治疗(PRFr)组(n=6);其中KOA组和PRFr组分别于术后第7天和第14天时向两侧关节腔内注射生理盐水和PRFr 0.5 mL。造模4、8周时,各组动物进行行为学评分、X线影像学观察,并取血清进行ELISA检测IL-1β、TNF-α、MMP-13水平,4周时KOA组处理6只,8周时处理各组剩余动物,取兔双侧膝关节,进行大体评分,脱钙后行病理切片制作,然后进行HE染色、甲苯胺蓝染色和番红O固绿染色以及TGF-β、BMP3和NF-κB免疫组化表达检测。结果与NC组比,造模后WHBE兔Lequesne MG行为学评分,Mankin’s评分,Pelletier评分均显著升高(P<0.01),可见膝关节肿胀明显、关节疼痛刺激和活动受限明显,且X光显示软组织呈高密度阴影,关节积液较多,解剖观察显示关节面粗糙,病理观察显示软骨表面缺损,软骨细胞丢失或部分丢失,表明WHBE兔KOA模型成立。与KOA组比较,PRFr干预治疗后血清炎症水平(IL-1β、TNF-α、MMP-13)均显著降低(P<0.05,P<0.01),软骨表面粗糙程度低,大部分软骨细胞分布整齐;同时TGF-β、BMP3和NF-κB表达水平亦显著降低(P<0.01)。结论本研究成功建立了WHBE兔KOA模型,且PRFr可通过TGF-β/BMP和NF-κB途径改善WHBE兔KOA模型软骨损伤和炎症。

Autologous peripheral blood-derived orthobiologics:Different types and their effectiveness in managing knee osteoarthritis

Knees are the most commonly impacted weight-bearing joints in osteoarthritis(OA),affecting millions of people worldwide.With increasing life spans and obesity rates,the incidence of knee OA will further increase,leading to a significant increase in the economic burden.Conventional treatment modalities utilized to manage knee OA have limitations.Over the last decade,the role of various autologous peripheral blood-derived orthobiologics(APBOs)for the treatment of knee OA has been extensively investigated.This editorial provided an overview and focused on defining and shedding light on the current state of evidence based on the most recent published clinical studies concerning the use of APBO for the management of knee OA.While numerous studies have demonstrated promising results for these preparations,a notable gap exists in the comparative analysis of these diverse formulations.This absence of head-to-head studies poses a considerable challenge for physicians/surgeons in determining the optimal preparation for managing knee OA and achieving sustained longterm results.Thus,more adequately powered,multicenter,prospective,doubleblind,randomized controlled trials with longer follow-ups are needed to establish the long-term efficacy and to aid physicians/surgeons in determining the optimal APBO for the management of knee OA.

Platelet-rich plasma gel in combination with Schwann cells for repair of sciatic nerve injury

Bone marrow mesenchymal stem cells were isolated from New Zealand white rabbits, culture-expanded and differentiated into Schwann cell-like cells. Autologous platelet-dch plasma and Schwann cell-like cells were mixed in suspension at a density of 1 x 106 cells/mL, prior to introduction into a poly （lactic-co-glycolic acid） conduit. Fabricated tissue-engineered nerves were implanted into rabbits to bridge 10 mm sciatic nerve defects （platelet-rich plasma group）. Controls were established using fibrin as the seeding matrix for Schwann cell-like cells at identical density to construct tissue-engineered nerves （fibrin group）. Twelve weeks after implantation, toluidine blue staining and scanning electron microscopy were used to demonstrate an increase in the number of regenerating nerve fibers and thickness of the myelin sheath in the platelet-rich plasma group compared with the fibrin group. Fluoro-gold retrograde labeling revealed that the number of Fluoro-gold-positive neurons in the dorsal root ganglion and the spinal cord anterior horn was greater in the platelet-rich plasma group than in the fibrin group. Electrophysiological examination confirmed that compound muscle action potential and nerve conduction velocity were superior in the platelet-rich plasma group compared with the fibrin group. These results indicate that autologous platelet-rich plasma gel can effectively serve as a seeding matrix for Schwann cell-like cells to construct tissue-engineered nerves to promote perJpheral nerve regeneration.

Platelet-rich plasma,an adjuvant biological therapy to assist peripheral nerve repair

Therapies such as direct tension-free microsurgical repair or transplantation of a nerve autograft,are nowadays used to treat traumatic peripheral nerve injuries（PNI）,focused on the enhancement of the intrinsic regenerative potential of injured axons.However,these therapies fail to recreate the suitable cellular and molecular microenvironment of peripheral nerve repair and in some cases,the functional recovery of nerve injuries is incomplete.Thus,new biomedical engineering strategies based on tissue engineering approaches through molecular intervention and scaffolding offer promising outcomes on the field.In this sense,evidence is accumulating in both,preclinical and clinical settings,indicating that platelet-rich plasma products,and fibrin scaffold obtained from this technology,hold an important therapeutic potential as a neuroprotective,neurogenic and neuroinflammatory therapeutic modulator system,as well as enhancing the sensory and motor functional nerve muscle unit recovery.

Erbium-doped yttrium aluminum garnet laser and advanced plateletrich fibrin+in periodontal diseases:Two case reports and review of the literature

BACKGROUND The goal of periodontal disease treatment is to completely remove bacteria and promote wound healing.The erbium-doped yttrium aluminum garnet(Er:YAG)laser is commonly used to treat periodontal disease.Advanced platelet-rich fibrin+(A-PRF+)secrets growth factors that accelerates soft-and hard-tissue regeneration and wound healing.Herein I present 2 cases of patients with oral diseases treated with a combination of Er:YAG laser and A-PRF+.CASE SUMMARY Case 1 was a female with pocket depth bone loss over 8 mm and infection of tooth 31 and 41,and severe advanced periodontitis with grade III mobility.Case 2 was a male with tooth 22 root end apical swelling and infection and alveolar bony defects.Clinical outcomes were recorded at 6 and 36 mo.In case 1,the Er:YAG laser was used to perform open flap debridement(100 mJ/pulse,15 Hz)and remove calculus and granulation tissue(50 mJ/pulse,30 Hz).In case 2 the laser was used to create a semilunar full thickness flap incision(80 mJ/pulse,20 Hz)and eliminate the pathogen(100 mJ/pulse,15 Hz).In both patients,A-PRF+mixed with bone was used to fill bone defects,and A-PRF+autologous membranes were used to cover tension-free primary flaps.There was no recurrent infection at 36 mo,and tissue regeneration and would healing occurred.CONCLUSION Debridement with an Er:YAG laser followed by treatment with A-PRF+is effective for the treatment periodontal diseases with bone defects.

富血小板纤维蛋白中生长因子含量及释放周期的实验研究

目的 比较分析富血小板血浆(PRP)与富血小板纤维蛋白(PRF)中转化生长因子-β3(TGF-β3)、血小板源生长因子-AA(PDGF-AA)和胰岛素样生长因子-1(IGF-1)总含量及生长因子释放周期。方法于2020年6—8月课题组招募10名健康成年人志愿者,同一时间段在双侧肘静脉各抽血5 ml,双侧均按随机数表法分为PRP组和PRF组,通过ELISA法检测两组标本中TGF-β3、PDGF-AA和IGF-1含量,比较分析生长因子含量和释放周期,通过电镜扫描观察PRF的显微结构。结果 PRP组血液标本中TGF-β3、PDGF-AA和IGF-1含量分别为(385.3±36.8)ng/ml、(113.8±17.4)ng/ml、(102.4±12.5)ng/ml,PRF组分别为(401.8±43.4)ng/ml、(128.5±19.1)ng/ml、(109.8±14.7)ng/ml,两组比较,差异无统计学意义(P> 0.05);PRP中TGF-β3、PDGF-AA和IGF-1等生长因子在3 d内达到释放高峰,1周内缓慢释放,PRF中TGF-β3、PDGF-AA和IGF-1在3周后持续缓慢释放,释放曲线相一致,但存在不同释放高峰时间点;扫描电镜观察结果显示PRF中胶原纤维束形态规则、结构清晰、表面光滑,纤维束之间相互交联缠绕,呈网状结构,内含大量细胞成分。结论 PRP与PRF标本中TGF-β3、PDGF-AA和IGF-1的释放总含量相似,但具有不同的释放高峰时间点,PRF具有独特的三维网状结构,可以容纳更多的小分子物质,因而具有更长的释放周期。

富血小板纤维蛋白上清改善大鼠特应性皮炎的实验研究

目的观察富血小板纤维蛋白上清(platelet rich fibrin-releasate,PRF-r)对2,4-二硝基氯苯(DNCB)诱导的大鼠特应性皮炎(atopic dermatitis,AD)的影响,并试图探索其可能的潜在机制。方法SD大鼠42只(含制备PRF-r所需的大鼠10只)随机分为正常对照组、模型组(DNCB)、糠酸莫米松乳膏组和PRF-r组4组,每组8只。抽取正常大鼠不抗凝尾静脉血制备PRF-r。通过反复局部应用DNCB在大鼠背部诱导AD。PRF-r组和糠酸莫米松乳膏组从造膜第7天开始连续涂抹10天。对AD部位进行临床皮肤评分。AD组织用苏木精-伊红(H&E)染色以观察皮肤病理学改变。采用酶联免疫吸附实验(ELISA)测定大鼠血清中白介素4(IL-4)和γ-干扰素(IFN-γ)水平。免疫组化检测AD部位IL-4和IFN-γ的表达。结果PRF-r显著减轻DNCB诱导的大鼠AD样症状,包括皮炎严重程度,降低了皮炎评分(PRF-r组:1.8±0.27,DNCB模型组:4.9±0.44)。进一步实验发现,与正常对照组大鼠血清IFN-γ(140.43±8.21)pg/mL和IL-4(206.63±2.17)pg/mL水平相比,DNCB诱导的模型组大鼠血清IFN-γ水平明显减少(114.21±6.67)pg/mL,IL-4水平增加(221.71±2.58)pg/mL。糠酸莫米松乳膏和PRF-r治疗后IFN-γ表达提升[(127.83±7.59)pg/mL,(145.66±7.92)pg/mL],IL-4水平回落[(210.45±4.15)pg/mL,(212.26±3.71)pg/mL],趋于正常组水平。免疫组化显示各组AD局部组织中IFN-γ和IL-4的表达与血清中趋势一致。结论PRF-r可能通过调节Th2型炎症反应和Th1/2细胞因子水平来改善DNCB诱导的大鼠AD。

化学去细胞同种异体神经复合缓释神经生长因子修复周围神经缺损

目的探讨化学去细胞异体神经复合缓释神经生长因子(nerve growth factor,NGF)修复周围神经缺损的效果。方法采用药物微球技术制备NGF微球,与生物纤维蛋白胶混合形成NGF复合缓释制剂。取健康雄性SD大鼠20只,体重280～300g,制备化学去细胞异体神经。取健康雄性Wistar大鼠52只,体重250～300g,制备大鼠左侧坐骨神经10mm缺损模型。根据修复缺损材料不同,随机分成4组(n=13):自体神经移植组(A组)、化学去细胞异体神经移植加NGF复合缓释制剂组(B组)、化学去细胞异体神经移植组(C组)和化学去细胞同种异体神经移植和纤维蛋白胶组(D组)。右侧不作处理作为空白对照组。术后行大体观察;术后2周测量神经轴突生长距离;术后16周行电生理检测,计算术侧坐骨神经运动传导速度恢复率、术侧小腿三头肌收缩力恢复率及湿重恢复率,并行移植神经吻合中段HE和半薄切片甲苯胺蓝染色观察。结果所有动物均存活至实验完成,切口愈合良好。术后2周A组神经再生距离较其余3组长(P<0.05),B组优于C、D组(P<0.05),C、D组间比较差异无统计学意义(P>0.05)。术后16周,A、B、C、D组术侧坐骨神经运动传导速度恢复率分别为73.37%±7.82%、70.39%±8.45%、53.51%±6.31%、55.28%±5.37%;A、B组与C、D组比较,差异有统计学意义(P<0.05)。A、B、C、D组术侧小腿三头肌收缩力恢复率分别为85.33%±5.59%、69.79%±5.31%、64.46%±8.49%、63.35%±6.40%;A组与B、C、D组比较差异有统计学意义(P<0.05),B、C、D组间比较差异无统计学意义(P>0.05)。A、B、C、D组术侧小腿三头肌湿重恢复率分别为62.54%±8.25%、53.73%±4.56%、46.37%±5.68%、45.78%±7.14%;A组与B、C、D组比较差异有统计学意义(P<0.05),B组与C、D组比较差异有统计学意义(P<0.05),C、D组间比较差异无统计学意义(P>0.05)。组织学图像分析示B组有髓神经纤维数量、轴突直径及髓鞘厚度均优于C、D组(P<0.05),B组轴突直径小于A组(P<0.05)。结论复合缓释NGF的化学去细胞同种异体神经能满意修复一定长度的周围神经缺损,是一种有效的周围神经组织工程修复材料。

SHH缓释纤维蛋白支架移植促大鼠脊髓损伤的修复

目的:研究应用可缓释音猬因子(sonic hedgehog,SHH)的纤维蛋白胶(fibrin glue,FG)支架促大鼠脊髓完全横断损伤的修复效果。方法:(1)制作体外缓释SHH的纤维蛋白胶支架模型,探究缓释效果。(2)选用健康的SD大鼠60只,制作大鼠脊髓完全横断模型,随机分为三组:单纯脊髓横断组(SCI),纤维蛋白胶组(FG),音猬因子-支架移植组(F-SHH)。术后每周记录大鼠双后肢功能活动(BBB评分)。术后12周取出脊髓组织,采用免疫组织化学染色和免疫蛋白印迹检测,观察脊髓损伤的近远端神经元存活情况及神经丝蛋白(neurofilament200,NF200),生长再生相关蛋白(growth associated protein-43,GAP43),胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)表达情况。结果:(1)载SHH的纤维蛋白胶具有良好的缓释SHH的效果;(2)F-SHH组BBB评分从术后到第十二周较FG、SCI组上升明显(P<0.05);(3)免疫组化结果显示:F-SHH组脊髓横断端有一些神经元存活且排列规则,许多神经纤维未完全溃变。SCI组细胞凋亡明显,纤维溃变严重,退变空泡大,FG组较SCI组稍好;(4)Western Blot结果显示:F-SHH组NF200,GAP43相对含量高于FG、SCI组(P<0.05),而GFAP相对含量低于FG、SCI组(P<0.05)。结论:SHH缓释纤维蛋白支架缓释效果良好,对大鼠脊髓完全横断损伤的修复有明显的促进作用,SHH对于脊髓损伤的修复机理值得进一步研究。