察爾斯大夫 美麗殿堂 Dr. Charles Meridien Palace

Platelet-rich fibrin（PRF）：a second-generation platelet concentrate. Part I：technological concepts and evolution.

David M. Dohan, DDS, MSa, , , Joseph Choukroun, MDb, Antoine Diss, DDS, MSc, Steve L. Dohand, Anthony J.J. Dohane, Jaafar Mouhyi, DDS, PhDf, Bruno Gogly, DDS, MS, PhDg

a Assistant Professor, Biophysics Laboratory, Faculty of Dental Surgery, University of Paris V; Department of Oral Surgery, Odontology Service, Hopital Albert Chenevier, Paris

b Private Practice, Pain Clinic Center, Nice, France

c Assistant Professor, Laboratory of Surface and Interface in Odontology, Odontology Faculty, Nice University; Department of Periodontology, Odontology Service, Hopital St Roch, Nice, France

d Student, Biophysics Laboratory, Faculty of Dental Surgery, University of Paris V; Odontology Service, Hopital Albert Chenevier, Paris

e Student, Saint-Antoine Faculty of Medicine, University of Paris VI

f Private practice, Casablanca, Morocco; Assistant Professor, Advanced Periodontology, University of Southern California; Researcher, Department of Biomaterials/Handicap Research, Institute for Surgical Sciences, Sahlgrenska Academy at Göteborg University

g Professor, Faculty of Dental Surgery, University of Paris V; Chief, Odontology Service, Hopital Albert Chenevier, Paris

Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006 Mar;101(3):e37-44. Epub 2006 Jan 19.

Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology

Volume 101, Issue 3, March 2006, Pages e37–e44

Source

Biophysics Laboratory, Faculty of Dental Surgery, University of Paris V, Paris, France. drdohand@hotmail.com

（http://www.sciencedirect.com/science/article/pii/S107921040500586X）

Abstract

Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates geared to simplified preparation without biochemical blood handling. In this initial article, we describe the conceptual and technical evolution from Fibrin glues to Platelet concentrates. This retrospective analysis is necessary for the understanding of fibrin technologies and the evaluation of the biochemical properties of 3 generations of surgical additives, respectively Fibrin adhesives, Concentrated Platelet-rich plasma (cPRP) and PRF. Indeed, the 3-dimensional fibrin architecture is deeply dependent on artificial clinical polymerization processes, such as massive bovine thrombin addition. Currently, the Slow polymerization during PRF preparation seems to generate a fibrin network very similar to the natural one. Such a network leads to a more efficient cell migration and proliferation and thus cicatrization.

Fig. 1. Technologic concept of cPRP processing

Fig. 2. Blood centrifugation immediately after collection allows the composition of a structured and resistant fibrin clot in the middle of the tube, just between the red corpuscles at the bottom and acellular plasma at the top.

Fig. 3. Blood processing with a PC-O2 centrifuge for PRF (A; Process, Nice, France) allows the composition of a structured fibrin clot in the middle of the tube, just between the red corpuscles at the bottom and acellular plasma at the top (B). After collection of the PRF itself (C), resistant autologous fibrin membranes are easily obtained by driving out the serum from the clot (D).

Fig. 4. Theoretical computer modelling of condensed tetramolecular or bilateral fibrin branch junctions. Note the rigidity of this architecture (D-TEP v1.3).

Fig. 5. Theoretical computer modelling of trimolecular or equilateral fibrin branch junctions. Note the flexibility of this net architecture (D-TEP v1.3).

Platelet-poor plasma（PPP）

From Wikipedia, the free encyclopedia

Platelet-Poor Plasma（PPP）is blood plasma with very low number of platelets（< 10 X 103/μL）.

Traditionally, PPP was recommended for use in platelet aggregation studies to both adjust the Platelet-rich plasma concentration, and to serve as a control.

PPP may have elevated levels of Fibrinogen, which has the ability to be form a fibrin rich clot once activated. Wound healing requires cell migration and attachment, which is facilitated by this fibrin clot.

Current Uses

Fibrin sealants have found use in many clinical situations such as blood management, orthopaedic surgery, and cosmetic surgery.

Future possibilities

As a by-product of PRP preparation, PPP may also find use in tissue engineering applications as an Autologous degradable scaffold. This plasma portion is frequently discarded when used with PRP treatments.

Platelet-rich Fibrin matrix for improvement of Deep nasolabial folds.

Sclafani AP.

J Cosmet Dermatol. 2010 Mar;9(1):66-71. doi: 10.1111/j.1473-2165.2010.00486.x.

Source

Division of Facial Plastic Surgery, The New York Eye & Ear Infirmary, New York, New York 10003, USA. asclafani@nyee.edu

Abstract

BACKGROUND :

Dermal augmentation continues to grow as an aesthetic facial procedure. Many exogenous filler materials rely on an autologous fibrotic response for volume augmentation.

AIMS :

To evaluate the efficacy of a single injection of autologous platelet-rich fibrin matrix (PRFM) for the correction of deep nasolabial folds (NLFs).

PATIENTS/METHODS :

Whole blood was obtained from 15 adults, and an activated autologous PRFM produced using a proprietary system (Selphyl; Aesthetic Factors, Inc., Wayne, NJ, USA) was then injected into the dermis and immediate subdermis below the NLFs. Subjects were photographed before and after treatment; NLFs were rated by the treating physician before and after treatment using the Wrinkle Assessment Scale (WAS) and patients rated their appearance at each post-treatment visit using the Global Aesthetic Improvement Scale. Patients were evaluated at 1, 2, 6, and 12 weeks after treatment.

RESULTS :

All patients were treated to maximal correction, no over-correction, with a mean reduction in WAS score of 2.12 +/- 0.56. At 1 week after treatment, this difference was 0.65 +/- 0.68, but rose to 0.97 +/- 0.75, 1.08 +/- 0.59, and 1.13 +/- 0.72 at 2, 6, and 12 weeks after treatment, respectively (P < 0.001). No patient noted any fibrosis, irregularity, hardness, restricted movement, or lumpiness.

CONCLUSIONS :

PRFM can provide significant long-term diminution of deep NLFs without the use of foreign materials. PRFM holds significant potential for stimulated dermal augmentation.

Platelet-rich Fibrin matrix improves wound angiogenesis via inducing endothelial cell proliferation.

Roy S, Driggs J, Elgharably H, Biswas S, Findley M, Khanna S, Gnyawali U, Bergdall VK, Sen CK.

Wound Repair Regen. 2011 Nov;19(6):753-66. doi: 10.1111/j.1524-475X.2011.00740.x.

Source

Comprehensive Wound Center, Department of Surgery, Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, Ohio 43210, USA.

Abstract

The economic, social, and public health burden of chronic ulcers and other compromised wounds is enormous and rapidly increasing with the aging population. The growth factors derived from platelets play an important role in Tissue remodeling including Neovascularization. Platelet-rich plasma (PRP) has been utilized and studied for the last four decades. Platelet gel and Fibrin sealant, derived from PRP mixed with Thrombin and Calcium chloride, have been exogenously applied to tissues to promote Wound healing, Bone growth, Hemostasis, and Tissue sealing. In this study, we first characterized recovery and viability of as well as growth factor release from platelets in a novel preparation of platelet gel and fibrin matrix, namely Platelet-rich fibrin matrix（PRFM）. Next, the effect of PRFM application in a delayed model of ischemic wound angiogenesis was investigated. The study, for the first time, shows the kinetics of the viability of platelet-embedded fibrin matrix. A slow and steady release of Growth factors from PRFM was observed. The Vascular endothelial growth factor released from PRFM was primarily responsible for endothelial mitogenic response via extracellular signal-regulated protein kinase activation pathway. Finally, this preparation of PRFM effectively induced endothelial cell proliferation and improved wound angiogenesis in chronic wounds, providing evidence of probable mechanisms of action of PRFM in healing of chronic ulcers.

2011 by the Wound Healing Society.

Platelet-rich plasma（PRP）and Platelet-Rich Fibrin（PRF）：Surgical adjuvants, preparations for in situ regenerative medicine and tools for tissue engineering.

Bielecki T, Dohan Ehrenfest DM.

Curr Pharm Biotechnol. 2012 Jun;13(7):1121-30.

Source

Department and Clinics of Orthopaedics, Medical University of Silesia, Sosnowiec, Poland. tomekbiel@o2.pl

Abstract

The recent developement of platelet concentrate for surgical use is an evolution of the Fibrin glue technologies used since many years. The initial concept of these autologous preparations was to concentrate platelets and their growth factors in a plasma solution, and to activate it into a fibrin gel on a surgical site, in order to improve local healing. These platelet suspensions were often called Platelet-Rich Plasma (PRP) like the platelet concentrate used in transfusion medicine, but many different technologies have in fact been developed; some of them are even no more platelet suspensions, but Solid fibrin-based biomaterials called Platelet-Rich Fibrin（PRF）. These various technologies were tested in many different clinical fields, particularly oral and maxillofacial surgery, Ear-Nose-Throat surgery, plastic surgery, orthopaedic surgery, sports medicine, gynecologic and cardiovascular surgery and ophthalmology. This field of research unfortunately suffers from the lack of a proper accurate terminology and the associated misunderstandings, and the literature on the topic is quite contradictory. Indeed, the effects of these preparations cannot be limited to their growth factor content: these products associate many actors of healing in synergy, such as Leukocytes, Fibrin matrix, and circulating Progenitor cells, and are in fact as complex as blood itself. If platelet concentrates were first used as surgical adjuvants for the stimulation of healing as Fibrin glues enriched with growth factors, many applications for in situ regenerative medicine and tissue engineering were developed and offer a great potential. However, the future of this field is first dependent on his coherence and scientific clarity. The objectives of this article is to introduce the main definitions, problematics and perspectives that are described in this special issue of Current Pharmaceutical Biotechnology about platelet concentrates.

Platelet-rich plasma（PRP）

From Wikipedia, the free encyclopedia

Platelet-rich plasma（PRP）is blood plasma that has been enriched with platelets. As a concentrated source of autologous platelets, PRP contains and releases（through degranulation）several different Growth factors and other Cytokines that stimulate healing of Bone and Soft tissue.

Components

The efficacy of certain growth factors in healing various injuries and the concentrations of these growth factors found within PRP are the theoretical basis for the use of PRP in tissue repair.

The platelets collected in PRP are activated by the addition of Thrombin and Calcium chloride, which induces the release of these factors from alpha granules.

The growth factors and other cytokines present in PRP include：

1、Platelet-derived growth factor

2、Transforming growth factor beta

3、Fibroblast growth factor

4、Insulin-like growth factor 1

5、Insulin-like growth factor 2

6、Vascular endothelial growth factor

7、Epidermal growth factor

8、Interleukin 8

9、Keratinocyte growth factor

10、Connective tissue growth factor

Preparation

There are, at present, two methods of PRP preparation approved by the U.S. Food and Drug Administration. Both processes involve the collection of whole blood（that is anticoagulated with Citrate dextrose）before undergoing Two stages of centrifugation（TruPRP）（Harvest）designed to separate the PRP aliquot from platelet-poor plasma and red blood cells.

In humans, the typical baseline blood platelet count is approximately 200,000 per µL; therapeutic PRP concentrates the platelets by roughly Five-fold.

According to several studies, Platelet Rich Plasma must contain platelet counts at least 4～6 times baseline in order to be therapeutic.

PRP is rich in platelet Growth factors as well as a Fibrin matrix.

Platelet Poor Plasma is a rich source of Fibrin matrix which has been used for Extra injection sites including the hands and upper arms, or a mask post laser resurfacing.

There is however broad variability in the production of PRP by various concentrating equipment and techniques.

Clinical applications

In humans, PRP has been investigated and used as clinical tool for several types of medical treatments, including Nerve injury, Tendinitis, Osteoarthritis, Cardiac muscle injury, Bone repair and regeneration, Plastic surgery, and oral surgery. PRP has also received attention in the popular media as a result of its use in treating sports injuries in professional athletes.

Clinical validity

The use and clinical validation of PRP is still in the early stages. Results of basic science and preclinical trials have not yet been confirmed in large-scale controlled clinical trials. For example, clinical use of PRP for nerve injury and sports medicine has produced "promising" but "inconsistent" results in early trials. A 2009 systematic review of the scientific literature stated that there are few controlled clinical trials that have adequately evaluated the safety and efficacy of PRP treatments and concluded that PRP is "a promising, but not proven, treatment option for joint, tendon, ligament, and muscle injuries".

Proponents of PRP therapy argue that negative clinical results are associated with Poor quality PRP produced by inadequate Single spin devices. The fact that most gathering devices capture a percentage of a given thrombocyte count is a bias, since there is significant inter-individual variability in the platelet concentration of human plasma. More is not necessarily better in this case. The variability in platelet concentrating techniques may alter platelet degranulation characteristics that could affect clinical outcomes.

Implications for doping

Some concern exists as to whether PRP treatments violate anti-doping rules, such as those maintained by the World Anti-Doping Agency. It is not clear if local injections of PRP can have a systemic impact on circulating cytokine levels, in turn affecting doping tests; it is also not clear whether PRP treatments have systemic anabolic effects or affect performance.

In January 2011, the World Anti-Doping Agency removed Intramuscular injections of PRP from its prohibitions after determining that there is a "lack of any current evidence concerning the use of these methods for purposes of performance enhancement".

Use of platelet-rich fibrin over skin wounds：Modified secondary intention healing（3）

Discussion        

Face being a highly aesthetic zone, the complexities in healing after any intervention poses a great challenge to the surgeon. Scar formation is one of the most undesirable outcomes of the healing process. Early primary closure helps minimize scars, but in cases where there is skin loss, it is not always achievable. This is true, especially in areas where undermining the adjacent tissue is not possible or it may distort facial symmetry.

It is certain that platelets play a prominent, if not deciding role, in wound healing. [2] Platelets release Cytokines and Growth factors during Clot formation at the wound sites. [3] Platelet activation in response to tissue damage and vascular exposure results in the formation of a Platelet plug and Blood clot to provide Hemostasis and the secretion of Biologically active proteins from the α-granules. These include platelet derived growth factor (PDGF), transforming growth factor (TGF), platelet factor 4 (PF4), interleukin (IL)-1, vascular endothelial growth factor (VEGF), platelet-derived angiogenesis factor (PDAF), epidermal growth factor (EGF), insulin-like growth factor (IGF), epithelial cell growth factor (ECGF), Osteonectin, Osteocalcin, Fibrinogen, Vitronectin, Fibronectin, and Thromboplastin. [2] These secretory proteins, in turn, initiate tissue healing. Healing includes cellular chemotaxis, proliferation, and differentiation and the removal of tissue debris, angiogenesis, laying down of extracellular matrix, and regeneration of the appropriate type of tissue. Platelets direct wound healing because, by design, they appear exactly where and when needed to create a local environment conducive to tissue regeneration and set the pace of wound healing with their effects lasting even after the clot has been cleared. The improvement of healing by the placement of a Supraphysiologic concentration of Autologous platelets at the site of tissue injury is supported by basic science studies. There are studies that provide evidence that the use of autologous platelet-rich plasma offers some efficacy in certain types of acute and chronic wounds and causes an increase in hard- and soft-tissue wound healing and a decrease in postoperative infection, pain, and blood loss. [2]

PRF is a second generation platelet concentrate with simplified processing without biochemical blood handling. It enmeshes glycosaminoglycans from the blood and platelets, which have a strong affinity with small circulating peptides and a great capacity to support cell migrations and healing processes.

Dohan et al. (2006) stated that PRF was a completely usable healing concentrate. [1]

Hom et al. (2007) in a study on the healing effects of autologous platelet gel (APG) on acute human skin wounds concluded that APG not only enhanced wound closure but also increased the wound healing velocity. [4]

Role of platelet-rich fibrin membrane in healing

Any avulsive wound gets covered with a blood clot. This clot is the focal point of initiating healing. A natural blood clot contains 5% Platelets, 95% Red blood cells, <1% White blood cells, and large amounts of Fibrin strands. A platelet-rich plasma (PRP) clot contains 95% Platelets, 4% Red blood cells, and 1% White blood cells. PRP is a first generation plasma concentrate. [5] Due to the various advantages of PRF over PRP and the ease of technique, PRF is preferred over the latter. PRF membrane is a simple approach of concentrating platelets or enriching natural blood clot, which forms in avulsive wounds, to initiate a more rapid and complete healing process.

PRF is an immune and platelet concentrate that collects on a single fibrin membrane; all the constituents of a blood sample are favorable to healing and immunity. [6] Although Platelet and Leukocyte cytokines are important in the biology of this biomaterial, the Fibrin matrix supporting them constitutes the determining element responsible for the real therapeutic potential of PRF. The PRF membranes simultaneously support the development of the three keys to healing and soft tissue maturation, namely, Angiogenesis, Immunity, and Epithelial cover. This membrane protects open wounds and accelerates healing, favors the development of Microvascularization, and also guides Epithelial cell migration to its surface. Furthermore, this matrix contains leukocytes and promotes their migration. Therefore, its utilization seems to be of high significance in the case of infected wounds, like that of rapid uneventful healing of a tooth socket filled with PRF. [6]

Since the healing that occurs by using this technique is neither by primary intention nor by pure secondary intention, we have termed it "Modified secondary intention healing." The efficacy of this treatment lies in the local delivery of a wide range of Growth factors and Proteins on a Fibrin mesh, mimicking and supporting physiological wound healing and reparative tissue processes, thereby resulting in a nearly scarless aesthetic wound healing.

References       

1.    Dohan DM, Choukroun J, Diss A, Dohan SL, Dohan AJ, Mouhyi J, et al. Platelet-rich fibrin (PRF): A second-generation platelet concentrate. Part II: Platelet-related biologic features. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:e45-50.

2.    Eppley BL, Pietrzak WS, Blanton M. Platelet-rich plasma: A review of biology and applications in plastic surgery. Plast Reconstr Surg 2006;118:147e-59e.

3.    Blanton MW, Hadad I, Johnstone BH, Mund JA, Rogers PI, Eppley BL, et al. Adipose stromal cells and platelet-rich plasma therapies synergistically increase revascularization during wound healing. Plast Reconstr Surg 2009;123:56S-64S.

4.    Hom DB, Linzie BM, Huang TC. The healing effects of autologous platelet gel on acute human skin wounds. Arch Facial Plast Surg 2007;9:174-83.

5.    Sunitha Raja V, Munirathnam Naidu E. Platelet-rich fibrin: Evolution of a second generation platelet concentrate. Indian J Dent Res 2008;19:42-6.

6.    Choukroun J, Diss A, Simonpieri A, Girard MO, Schoeffler C, Dohan SL, et al. Platelet-rich fibrin (PRF): A second-generation platelet concentrate. Part IV: Clinical effects on tissue healing. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;101:e56-60.

Correspondence Address :

Chirag B Desai

Department of Oral and Maxillofacial Surgery, Rural Dental College, Pravara Institute of Medical Sciences, Loni, Ahmednagar - 413 736, Maharashtra

India

DOI: 10.4103/0974-2077.110096

Use of platelet-rich fibrin over skin wounds：Modified secondary intention healing（2）

About 10 ml of venous blood was withdrawn to prepare PRF by Choukroun's protocol [Figure 2]. [1] The sampled blood was transferred into glass test tubes. It was then centrifuged at 3000 rpm for 10 min in a laboratory centrifuge. At the end of the centrifugation, three distinct layers could be seen in the test tube. The uppermost layer was Platelet poor plasma, the middle layer was Platelet rich fibrin, and the lowermost layer was Red blood cells. The middle layer of PRF was separated and squeezed between two layers of sterile gauze. The PRF membrane thus obtained was placed over the defect [Figure 3]. A Double layer of the membrane was placed over Deeper areas of the Defect to achieve an even surface. Neglecting this step could lead to an uneven surface and formation of a scar on healing; this was covered by a single layer of Moist gauze and Micropore dressing. A gradual decrease in the size of the wound and granulation tissue formation was observed in the subsequent visits [Figure 4]. There were no signs of inflammation or infection. It was observed that the PRF-treated site showed hastened healing with early wound contracture. In the subsequent visits, the color of the reconstructed region was comparable to the adjacent uninjured tissue. The defect in the vermilion border and the white roll was inconspicuous [Figure 5]. 

Figure 2 : Processing of platelet-rich fibrin

Figure 3 : Platelet-rich fibrin membrane

Figure 4 : Two weeks follow up

Figure 5 : Six weeks follow up

Classification of Platelet concentrates：from Pure platelet-rich plasma（P-PRP） to Leucocyte- and platelet-rich fibrin（L-PRF）（4）

Figure 4. Schematic illustration of the matrix and cell architecture of the four categories of platelet concentrates. Two key parameters are important: Leucocyte content (blue circles) and density of Fibrin (yellow/light-brown fibres). Platelet aggregates (light-grey shapes) are always assembled on the fibrin fibres. In typical P-PRP and L-PRP preparations (top panels), the fibrin network is immature and consists mainly of fibrillae with a small diameter (red arrows) due to simple fibre polymerization. This fibrin network supports platelet application during surgery but dissolves quickly like a fibrin glue. In P-PRF and L-PRF preparations (bottom panels), fibrin fibres are thick (black arrows) due to multiple fibre assembly and constitute a resistant matrix that can be considered as a fibrin biomaterial.

Classification of Platelet concentrates：from Pure platelet-rich plasma（P-PRP） to Leucocyte- and platelet-rich fibrin（L-PRF）（3）

Figure 3. Choukroun's platelet-rich fibrin (PRF) method 21, 22, 23, 24, 25, 26, 27, 28, 29 and 30.

(a) Blood is softly centrifuged immediately after collection without anticoagulants, and coagulation starts quickly. Blood is separated into three components with the formation of a strong fibrin clot in the middle of the tube. This clot acts as a plug that traps most light blood components, such as platelets and leucocytes, as well as circulating molecules, such as growth factors and fibronectin. This method leads to the natural production of a dense leucocyte-rich PRF (L-PRF) clot.

(b) After compression of the L-PRF clot, it can be used easily as a membrane (actual length shown: 3 to 4 cm).

Classification of Platelet concentrates：from Pure platelet-rich plasma（P-PRP） to Leucocyte- and platelet-rich fibrin（L-PRF）（2）

Figure 2. Commonly described protocol for Anitua's PRGF 10, 11, 12, 13 and 14.

Step 1: Citrated blood in 5 mL tubes is softly centrifuged 8 min at 460 g and separated into three layers: RBC base, buffy coat (BC) and acellular plasma. Acellular plasma contains the empirically defined layers plasma poor in growth factors (PPGF) and plasma rich in growth factors (PRGF).

Step 2: The PPGF layer (1 ml) is discarded, and the PRGF, just above the BC, is collected by careful pipetting. PRGF from all sample tubes is collected into one tube and Calcium chloride is added for clotting.

Classification of Platelet concentrates：from Pure platelet-rich plasma（P-PRP） to Leucocyte- and platelet-rich fibrin（L-PRF）（1）

David M. Dohan Ehrenfest , Lars Rasmusson, Tomas Albrektsson

Department of Biomaterials, Institute of Clinical Sciences, The Sahlgrenska Academy at University of Gothenburg, Sweden

（http://www.sciencedirect.com/science/article/pii/S0167779909000158）

The topical use of platelet concentrates is recent and its efficiency remains controversial. Several techniques for platelet concentrates are available; however, their applications have been confusing because each method leads to a different product with different biology and potential uses. Here, we present classification of the different platelet concentrates into four categories, depending on their leucocyte and fibrin content：pure platelet-rich plasma（P-PRP）, such as cell separator PRP, Vivostat PRF or Anitua's PRGF; Leucocyte- and platelet-rich plasma（L-PRP）, such as Curasan, Regen, Plateltex, SmartPReP, PCCS, Magellan or GPS PRP; Pure plaletet-rich fibrin（P-PRF）, such as Fibrinet; and Leucocyte- and platelet-rich fibrin（L-PRF）, such as Choukroun's PRF. This classification should help to elucidate successes and failures that have occurred so far, as well as providing an objective approach for the further development of these techniques.

Figure 1. Classical manual platelet-rich plasma (PRP) protocol using a two-step centrifugation procedure 8 and 16.

Step 1: Whole blood is collected with anticoagulants and briefly centrifuged with low forces (softspin). Three layers are obtained: red blood cells (RBCs), ‘buffy coat’ (BC) layer and platelet-poor plasma (PPP). Buffy coat（BC）is typically of whitish colour and contains the major proportion of the Platelets and Leucocytes.

Step 2A: For production of pure PRP (P-PRP), PPP and superficial BC are transferred to another tube. After hardspin centrifugation (at high centrifugal force), most of the PPP layer is discarded. The final P-PRP concentrate consists of an undetermined fraction of BC (containing a large number of platelets) suspended in some fibrin-rich plasma. Most leucocytes are not collected.

Step 2B: For production of leucocyte-rich PRP (L-PRP), PPP, the entire BC layer and some residual RBCs are transferred to another tube. After hardspin centrifugation, the PPP is discarded. The final L-PRP consists of the entire BC, which contains most of the platelets and leucocytes, and residual RBCs suspended in some fibrin-rich plasma. Therefore, the final product greatly depends on the means of BC collection. The transfer step is often performed with a syringe or pipette, with only eyeballing as measuring tool. Because the manual PRP process is not clearly defined, this protocol might randomly lead to P-PRP or L-PRP.

Use of platelet-rich fibrin over skin wounds：Modified secondary intention healing（1）

Chirag B Desai1, Uma R Mahindra1, Yogesh K Kini2, Makarand K Bakshi1

1 Department of Oral and Maxillofacial Surgery, Rural Dental College, Pravara Institute of Medical Sciences, Loni, Ahmednagar, India

2 Department of Oral and Maxillofacial Surgery, Dr. D.Y. Patil Dental College, Mumbai, Maharashtra, India

Date of Web Publication   4-Apr-2013

CASE REPORT     

Year : 2013 | Volume : 6 | Issue : 1 | Page : 35-37

Abstract     

The healing process after any surgical intervention has always posed a challenge for the surgeons. In spite of the advances in wound closure techniques and devices, there is a crucial need for newer methods of enhancing the healing process to achieve optimal outcomes. Fibrin adhesives and Platelet concentrates have proven useful in various treatment modalities in the fields of microvascular and plastic surgery. This case report shows its unique use in the field of maxillofacial and cutaneous surgery. It shows an innovative technique of enhancement of skin wound healing by local application of Platelet-rich fibrin.

Keywords : Biologic dressing, modified secondary intention healing, platelet-rich fibrin

（http://www.jcasonline.com/article.asp?issn=0974-2077;year=2013;volume=6;issue=1;spage=35;epage=37;aulast=Desai）

How to cite this article:

Desai CB, Mahindra UR, Kini YK, Bakshi MK. Use of platelet-rich fibrin over skin wounds: Modified secondary intention healing. J Cutan Aesthet Surg 2013;6:35-7

How to cite this URL:

Desai CB, Mahindra UR, Kini YK, Bakshi MK. Use of platelet-rich fibrin over skin wounds: Modified secondary intention healing. J Cutan Aesthet Surg [serial online] 2013 [cited 2013 Sep 28];6:35-7.

Available from: http://www.jcasonline.com/text.asp?2013/6/1/35/110096.

Introduction     

Despite the modern advances in wound closure techniques and devices, there is a vital need for newer methods of enhancing the healing process to achieve optimal outcomes. Wound healing is a complex sequence of intracellular and extracellular events regulated by signaling proteins. This process is, at present, not completely understood. One of the promising, but complicated areas of recent therapeutic development involves topical application of growth factors to enhance the normal healing process. This case report shows an innovative technique of enhancement of healing of skin wounds by local application of Platelet-rich fibrin（PRF）as a Biological dressing.

Case Report      

A 30-year-old man who suffered a motorcycle accident, reported to the Department of Oral and Maxillofacial Surgery, presenting with an avulsive wound, approximately 0.5 × 1 cm in size, on the lower lip in the midline region with a disruption of the vermilion border and a white roll [Figure 1]. The depth of the wound was uneven with muscle tissue loss in some regions. The patient had no medical history. Primary closure could have caused pouting of the lip. Healing by secondary intention could have resulted in fibrosis and development of a hideous scar. Therefore, it was decided to treat the defect by local application of a PRF membrane.      

Figure 1：Avulsive wound over the lower lip

切膚培養「誘導多功能幹細胞（iPSC）」　北榮培養「視網膜組織」和「會跳動的心臟組織」

NOWnews – 2013年9月30日

記者陳鈞凱／台北報導

切一小塊皮膚，就能從頭到腳「複製」人，不再是科幻電影情節。台灣幹細胞研究有大突破，台北榮總前後花費2年時間，一一比對，找出幹細胞分化的關鍵基因「Parp1」，進一步培養出的「誘導多功能幹細胞（iPSC）」沒有引發癌化疑慮，目前已成功培養出視網膜組織和會跳動的心臟組織，初步運用於篩選治療藥物。

傳統的「胚胎幹細胞」必須破壞受精孕，作法備受宗教、道德爭議，日本學者山中伸彌發明的「誘導多功能幹細胞（iPSC）」，則是在皮膚送入特定的基因使細胞進行重新編程，同樣具有類似胚胎幹細胞的特性與功能，去年一舉拿下諾貝爾醫學獎。

陽明大學藥理所教授、台北榮總教研部主治醫師邱士華表示，問題在於，山中伸彌所使用的其中一項「c-myc」基因，本身就是癌症基因，可能引發癌化與腫瘤發生的疑慮，北榮研究團隊則利用高機密質譜儀，2年間，一一比對核蛋白，這才找出可以成功取代的「Parp1」基因，讓iPSC一樣能夠發揮功效，卻不會致癌。

利用取下0.5乘0.5公分大小皮膚，再送入「Parp1」等4項基因，北榮研究團隊目前已成功培養出視網膜色素上皮細胞以及心肌細胞，初步運用在測試高血壓、強心針藥物等，好篩選出對病人最有效的治療藥物；未來也考慮申請臨床人體實驗，距離複製器官更進一步。

邱士華說，過去測試藥物，受限於沒辦法活生生切下病人的一塊組織，難以篩選出對個人最佳化的藥物，但現在可以培養出病人的iPSC，一一測試，已發現包括維生素C、薑黃素等成分對治療視網膜遺傳性疾病，反應都不錯，可供做為新藥開發之用。

邱士華強調，利用iPSC可以培養出心臟、眼睛、神經等各部位，未來應用範圍極廣泛，只要取得病人的細胞，就可以客製病人專屬的「個人化誘導多功能幹細胞」，進而開發個人化藥物。

北榮這項新發現與突破性的技術，不但已經刊登在國際頂尖醫學期刊「Journal of Experimental Medicine」上，並已申請世界多國專利，更獲山中伸彌主動來函高度肯定。

台北榮總「切膚」培養萬能幹細胞　分化誘導視網膜細胞和心肌細胞複製器官快「成真」

作者：蔣志偉 | TVBS – 2013年9月30日

這幾年醫學發展突飛猛進，未來真的會有複製人出現嗎？台北榮總花了近2年時間找出幹細胞，可以從皮膚切片加入研發新基因，讓細胞變成萬能幹細胞，進而分化出視網膜細胞和心肌細胞，可有效地治療失明，也能讓心臟病患者心跳變快、收縮力更強，最重要的是萬能幹細胞能篩選有效的治療藥物，而未來若技術成熟，可複製各種人體組織，甚至是器官，複製人將有可能會成真。

電影《絕地再生》一群複製人住在地底，每當地上主人生病、需要器官時，就會從這些複製人身上拿走，劇中人類只要有病痛就可透過再生複製人，從身上取得移植，恢復健康，這樣的情節在現實生活裡似乎也能如法炮製嗎？

台北榮總研究幹細胞多年，領先全球第一個發現幹細胞同樣也可以從人體複製，也就是說只要切下皮膚細胞，再加入研發新基因，就能讓細胞變成萬能幹細胞，細胞分化後可再誘導為視網膜和心肌細胞，可用來治療眼睛黃斑性病變和受損視網膜，治療失明。

榮總眼科部主治醫師邱士華：「視網膜可以應用在，不僅應用在藥物篩選之外，特別對於黃斑性病變可以進行移植手術，讓病人重獲光明。」

過去臨床經驗只能透過新藥實驗，讓病患吞服後試藥，現在心臟病患者能從皮膚透過試藥試驗，培養出心肌幹細胞，病患治療前心跳慢、收縮力弱，而培養出來的心肌細胞可讓心跳變快、收縮力變得更強。

榮總眼科部主治醫師邱士華：「篩選藥物，心臟病患者能夠在藥物上面得到最佳化的結晶。」

醫師不諱言，誘導幹細胞成功率大幅提升，未來民眾能透過皮膚、臍帶血，甚至是牙髓和血液，經由客製化服務，建立屬於自己誘導幹細胞。

這個重大研究登上國際頂尖醫療期刊，雖然目前還在臨床實驗階段，預計要再等個3～5年後，民眾就能透過幹細胞開發自個兒專屬藥物，治療疾病。

Autolgous Growth Factor Concentrate：AGF凍晶

2012年7月26日中國時報【台中訊】

常人總說「年齡是女人的秘密」，但對多數女人而言，年齡就算嘴巴不說，也能從肌膚上看出歲月痕跡。而並非每個人與生俱來就能擁有麗質天生的幸運，在先天不足、後天不努力的狀況下，如不靠技術就想保有年輕，可說是天方夜譚。莎士比亞有句名言：【上帝給了女人一張臉，女人還自己創造出另一張臉】看來這句古老諺語似乎與現今整型醫美有著異曲同工之處。

而就在醫學美容不斷推陳出新的現今，日前更有業者再度研發出一套先進的技術AGF凍晶生長因子，這項生物科技革命的新體驗，標榜以先進、具突破性及安全的美容概念，以依賴人體血小板的自我修復功能為原理，增進幹細胞與修復細胞的分化，形成新的血管，促進膠原蛋白合成。

抗老專家黃禎淦醫師說明，具有〝啟動青春之鑰〞之稱的AGF凍晶（Autologous growth factor concentrate），其實就是由PRP演變而來。

綜觀市場，現今PRP因子已廣泛的被利用在醫美市場上，但就臨床實驗指出，如PRP因子未被刺激活化，其所釋放的再生功能效果有限，而AGF凍晶生長因子就是PRP經刺激活化的代名詞，讓血小板完整釋放出自體生長因子，可在皮膚底層產生大量的膠原蛋白，活化肌膚。

除外，黃禎淦醫師也補充，在凍齡回春此一話題上，微整注射也是熱門選項，不論是肉毒桿菌、玻尿酸或是微晶瓷，都很常見用於填補全臉凹陷或加強輪廓線。為此黃禎淦醫師說明，當今愛美人士想要凍齡或是回春，無不希望講求立即見效、維持長久，加上許多患者對於〝美〞有著相當大的主觀迷思，也因此在自我要求愈來愈高，且初老症狀逐漸受重視的關係鏈下，似乎永遠都有無法滿足的需求。

一直致力於各種抗老回春技術的黃禎淦醫師最後提醒，民眾如想針對面容做全面性調整，其實第一步應先針對底層基礎做保養及改善，由根本去瞭解自身膚質狀況及初老症狀，再對症下藥選擇合適的調整方法，才能降低使用肉毒桿菌或玻尿酸等注射的頻率。

AGF：Autologous Growth Factor 自體生長因子

人體血小板內含有豐富生長因子可改善肌膚老化。

採用來自瑞士的Regen Lab的RegenKit系統，證實萃取出的血小板是一般萃取方式的4倍濃度，並經由自體的凝血酶（Human Thrombin）促使血小板釋放出高濃度的9大類自體生長因子，可以快速達到啟動青春之鑰，看起來回復年輕。

1. AGF機轉祕密

血漿濃度達到正常血小板濃度4～5倍時，會引發體內細胞的增值與分化，而AGF是一種藉由自體血液細胞分離濃縮後可直接萃取出血小板中的生長因子，其中血小板的含量高過1,000,000/mm3（每立方毫米中超過100萬的血小板含量），較約一般血液高出2～6倍，可快速刺激自體細胞更新作用，讓肌膚重生！

2. Regen Lab的Regen Kit系統

瑞士Regen Lab的Regen Kit系統，有紅管及藍管，紅管在血液的離心過程可以離心出純化的PRP，還可以激活自體凝血酶（Human Thrombin），藍管在血液離心過程可以離心純化並具有活性的PRP，在藍管與紅管比例上7：3的調配，可以將藍管內的純化PRP激活出273倍的PRP能力，讓抗衰老拉提緊緻肌膚的功效，更加明顯，效果的持久。

試管嬰兒成敗主要關鍵取決於媽媽年齡

作者：【記者蔡清欽／台南報導】 | 台灣新生報 – 2013年9月23日

台南市郭綜合醫院婦產部長林大欽強調，人工生殖醫學應用在治療不孕症是當前的主流趨勢，但試管嬰兒成敗，以他多年實務經驗，最主要因素是產婦年齡，年齡愈輕懷孕率越高，反之亦然。

林大欽部長說，有些病人接受過卵巢手術，卵子數目變少，抗穆勒式賀爾蒙（AMH）值降低，但只要年齡尚輕，懷孕機會還是很高，可能要施打較多的排卵針，做試管嬰兒的次數也可能增加，因而花費亦較大，因此，他提醒不孕症治療宜趁早，及早治療事半功倍。

林大欽領軍的郭綜合醫院醫研部、護理部、檢驗部組成的醫療團隊，所研究「12周中高劑量去氫皮質酮素（DHEA）對卵巢儲能不足患者在AMH幫助」專題論文，在台灣生殖醫學會102年度年會獲獎，並在會中發表研究所得，成果受到與會生殖醫學界的重視。

抗穆勒氏賀爾蒙激素名字的由來，是因這種賀爾蒙於男性胎兒發育8周到13周時，在要形成睪丸的組織中被發現有這種賀爾蒙存在，如果沒有這種賀爾蒙出現，則發育成女性子宮、輸卵管、陰道。

林大欽表示，AMH目前在臨床上的應用，是可作為卵巢內尚存有多少卵子的指標，它預測卵巢功能的準確率比測量濾泡刺激賀爾蒙、抑制素Ｂ或卵巢內有腔濾泡數目的多寡來得高。血液中AMH值不隨月經周期、有無懷孕、有無服用賀爾蒙如避孕藥等而變動。

AMH值隨年齡變動，年齡愈高值愈小，到更年期降至0。

接受卵巢手術後因卵巢組織變少會使AMH值變低；AMH數值過低要考慮用增加卵子數目的策略，數值高則要減少排卵針劑量，避免產生卵巢過度刺激症候群。

泰專家警告幹細胞治療恐致命

中央社 – 2013年9月7日

（中央社記者林憬屏曼谷7日專電）

泰國英文報刊「民族報」（The Nation）今天報導，6個醫療專家團體警告，無照幹細胞治療可能會讓病人致死。

皇家醫師學院（Royal College of Physicians）、皮膚病學會（Dermatological Society）、泰國心臟協會（Heart Association of Thailand）、泰國血液學會（Thai Society of Haematology）、腎臟病學會（Nephrology Society）、神經內科學會（Neurology Society）昨天共同發表聲明，警告泰國民眾。

聲明指出，僅有泰國醫學委員會（Medical Council of Thailand）獲准使用幹細胞治療血液疾病，像白血病、惡性淋巴瘤、貧血等。

皇家醫師學院院長克林（Kriang Tungsanga）表示，研究幹細胞治療疾病的成效仍持續進行，但目前沒有科學證明，幹細胞治療可以有效延長壽命，或延緩器官惡化、甚至改善病人生活品質。

報導指出，最近有關幹細胞的「奇蹟藥片」廣告到處流傳，聲稱糖尿病、心臟病等慢性疾病可以減緩症狀。

無照人員執行的幹細胞治療心臟病、糖尿病或美容行為在名流間越來越普遍，要價從10萬銖（約合新台幣9.2萬元）到100萬銖不等。

報導指出，有些病人甚至專程赴德國的私人診所注射幹細胞，因他們深信可改善健康或看起來更年輕。

克林（Kriang Tungsanga）不建議施行幹細胞治療，他指出，不適當使用幹細胞治療不只在泰國，錯誤使用幹細胞治療對病人有害，可能造成過敏或血管凝血、血液污染、癌細胞轉移等。

他說，病人希望達到的治療效果與現階段醫療科技有差距，無法滿足他們的希望，問題出在不懂及懂得醫療科學之間的差距。