• The Journal of Korean Academy of Prosthodontics
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• v.42 no.2
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• pp.175-191
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• 2004

Statement of problem: Platelet-rich plasma(PRP) is well known to be very effective method to stimulate and accelerate the healing of bone and soft tissue. However, there are few reports which deal with the mechanisms of the PRP on the activation of the osteoblasts. Purpose: This study was aimed to investigate the effect of growth factors in PRP on the activity of osteoblasts. Material and method: To evaluate the effect on human, human osteoblast cell line was cultured. PRP was extracted from the blood of a healthy volunteer. Using the recombinant growth factors of PDGF, $TGFT-\beta$, IGF-1, bFGF which are mainly found at bone matrix and their neutralizing antibody, the effect of PRP on the attachment and proliferation of osteoblasts was evaluated. To evaluate the autocrine and paracrine effects, conditioned media(CM) of PRP was made and compared with PRP. By the western blot analysis, the expression of growth factors in PRP, CM was examined. Cell morphology was compared by the light microscope. Results : 1) The effects of CM on osteoblast were similar to the effects of PRP. 2) PRP, CM, recombinant $TGF-\beta$, bFGF, IGF-1 showed significantly higher cellular attachment than control(p<0.05) in the cell attachment assay. In the cell proliferation assay, PRP, CM, recombinant $TGF-\beta$, IGF-1, bFGF, PDGF increased significantly cell proliferation(p<0.01). Among the recombinant growth factors, IGF-1 showed the highest cellular attachment and proliferation. 3) In the western blot assay, bFGF, IGF-1, PDGF weve equally expressed in PRP and CM. 4) The attachment of osteoblast cell decreased significantly after the addition of neutralizing antibody against $TGF-\beta$, IGF-1(p<0.05). In the cell proliferation assay, the addition of neutralizing antibody against $TGF-\beta$, bFGF, PDGF, IGF-1 decreased significantly the cellular proliferation(p<0.05). The amount of decreasing in the cell attachment and proliferation is the highest in at-lGF-1. 5) The cells in control group were flattened and elongated with a few cellular processes in the a light microscope. But, the cells appeared as spherical, plump cells with well developed cellular processes in experimental groups. The cells in PRP and CM had more prominent developed features than recombinant growth factor groups. Conclusions : These findings imply that PRP maximize the cellular activity in early healing period using the synergistic effect, autocrine, paracrine effects of growth factors and increase the rate and degree of bone formation.

• Archives of Plastic Surgery
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• v.34 no.3
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• pp.291-297
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• 2007

Purpose: Platelet-rich plasma(PRP) contains protein growth factors, which are actively secreted by platelets to promote wound healing. However, it is not clear whether the injection of PRP into the autologous fat grafts increases the survival rate and the degree of angiogenesis. Methods: New Zealand White rabbit ears were injected fat with PRP, saline, insulin or isoproterenol (n=8/each group) for observation of the survival and degree of angiogenesis of the injected fat. The volume of the harvested fat and the degree of angiogenesis from dorsum of rabbit ears were evaluated 4, 8, and 12 weeks after the autologous fat graft. The degree of angiogenesis was measured with microvascular density (MVD) counts. Results: The volume of harvested fat decreased in a time-dependent manner after autologous fat grafts, but the decrease rate in volume of harvested fat was slower in PRP-injected group compared to that of other control groups. The difference in the volume of the harvested fat between PRP-injected group and other control groups became significant from 4 weeks after the autologous fat graft, and was maintained up to 12 weeks. However, there was no significant difference between PRP-injected group and insulin-injected group 8 and 12 weeks after the autologous fat graft. On the contrary, MVD counts increased in a time-dependent manner after autologous fat grafts. The MVD counts were significantly higher in PRP-and insulin-injected groups than in other control groups from 4 weeks after the autologous fat graft, and these differences were maintained up to 12 weeks. There was no correlation between mean platelet numbers and the volume of harvested fat. Conclusion: The present study demonstrates that PRP-injection into autologous fat grafts increases the survival rate and the degree of angiogenesis. Thus, PRP injection with autologous fat grafts would be a promising tool for maintaining the volume of the grafted fat.

• The Journal of the Korean bone and joint tumor society
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• v.16 no.1
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• pp.8-13
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• 2010

Purpose: This study was performed to evaluate the effi ciency of Platelet-rich plasma (PRP) for acceleration of bone healing process on allograft transplantation after curettage in benign bone tumor. Materials and Methods: From December 2007 to February 2009, twenty-one patients who had benign bone tumor and underwent allograft transplantation after curettage were evaluated. Mean follow-up period was 14.6 months (range, 12-26 months). We compared with 13 cases of PRP group and 8 cases of non-PRP group in terms of size of lesion, bone resorption, amount of applied PRP and complications. The mean age at surgery was 23.6 years (range, 4-73 years). The most common diagnosis was simple bone cyst (7) followed by enchondroma (4), giant cell tumor (3), undifferentiated benign bone tumor (3) and so on. Results: The mean size of lesion was 33.5 $cm^3$ (range, 2.3-181.9 $cm^3$) (29.4 $cm^3$ in PRP group and 40.2 $cm^3$ in non-PRP group). The mean volume of injected PRP was 7.4 cc (range, 3-12 cc). Bone union started at 3.0 months (range, 1.5-5.8 months) in PRP group and 5.3 months (range, 4-8 months) in non-PRP group. Three cases for each group were excluded due to recurrence and pathologic fracture. One patient had febrile episode 3 weeks later after surgery which subsided with antibiotics. Conclusion: The PRP could accelerate bone union in allograft transplantation after curettage of benign bone tumor. Furthermore, we expect that PRP can accelerate bone union in fracture or non-union.

• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.513-529
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• 2001

For reconstruction of the bony defect, various artificial substitutes were developed. Among them, there has been a study of calcium phosphate coated bone substitutes for increasing attachment of osteoblasts in vivo. The purpose of this study was to evaluate the effects of serum and platelet-rich plasma (PRP) on calcium phosphate coated culture plate for the initial attachment, proliferation and activity of osteoblasts. After sampling the blood from white rats and concentrating by centrifugation, the amount of attachment of PDGF-BB and $TGF-{\beta}$ on the calcium phosphate coated culture plate was measured. Cultured HOS and ROS 17/2.8 cell was measured on attachment level and proliferation rate of osteoblasts. Alkaline phosphatase activity of HOS and ROS 17/2.8 cell was measured for studying on the activating rate of osteoblast. 1. Counting the amount of platelets of seperated plasma and PRP, the average number of platelets was 177,003 $cell/{\mu}l$ in plasma, and 1,656,062 $cell/{\mu}l$ in PRP, which was about 9 times as high as in plasma. 2. Amount of PDGF-BB deposited at calcium phosphate coated plate had increased by the total amount of plasma and PRP on the culture plate, whereas $TGF-{\beta}$had been deposited on the plate only when treated by $50{\mu}{\ell}$ of PRP(p<0.01). 3. After plating serum and PRP for 3 hours, we attached with HOS and ROS17/2.8 cell for 1 hour and 4 hours. There were no significant difference of the attachment between serum and control group, whereas there were significantly difference of the attachment between depositioning of PRP and control group. 4. After attaching plasma and PRP for 3 hours, cell number has much increased when HOS and ROS17/2.8 cell had been cultured for 48 hours(p<0.05). 5. After attaching plasma and PRP for 3 hours, concentration of alkaline-phosphatase has increased when HOS and ROS17/2.8 cell had been cultured for 48 hours(p<0.01). These results suggested that PRP affected on initial cell attachment rather than proliferation and activation of osteoblasts at calcium phosphate coated plate.

• Asian Oncology Nursing
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• v.12 no.4
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• pp.323-330
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• 2012

Purpose: Gamma knife radiosurgery (GKR) requires frame positioning because the treatment target should be as close as possible to the center of the frame. The purpose of this study was to identify the level of pin-fixing (PFP) and removal pain (PRP), and the associated factors with the pain undergoing GKR. Methods: A total of 116 patients who underwent GKR for their brain tumor were recruited from C University hospital located in H city, J province. The level of pain was measured by the 10 cm VAS. Results: The level of PFP and PRP were 6.36 and 3.26 points, respectively. Step-wise multiple regressions found that the group who have not perceived numbness after applying 5% EMLA cream was the highest associated factor with PFP, following the time from lidocaine injection to pin-fixation, which explained 21% of total variance of the level of PFP. On the other hand, a group who did not perceive numbness after applying 10% lidocaine spray was the highest factor with PRP, among female patients, which explained 27% of total variance of the level of PRP. Conclusion: Both of PFP and PRP of the stereotactic frame were moderate so that nurses should consider diverse strategies to reduce pain among patients undergoing gamma knife radiosurgery.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.16-27
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• 2010

Purpose: The aim of this experimental study is to observe the effect of platelet-rich plasma (PRP) on early bone regeneration of rats both in normal condition and in osteoporosis induced by ovariectomy. Material and methods: Total 40 Sprague-Dawley female rats were divided into 4 groups. A 8-mm-diameter calvarial critical-sized defect (CSD) was made by drilling with trephine at the center of calvaria in cranium of every rat. Every CSD was augmented with an osteoconductive synthetic alloplastic substitute ($MBCP^{TM}$) and PRP as follows. Group A; 10 non-ovariectomized rats grafted with only $MBCP^{TM}$. Group B; 10 non-ovariectomized rats grafted with $MBCP^{TM}$ and PRP. Group C; 10 ovariectomized rats grafted with only $MBCP^{TM}$. Group D; 10 ovariectomized rats grafted with $MBCP^{TM}$ and PRP. At 4 weeks after graft, every rat was sacrificed. And histomorphometric analysis was performed by measuring calcified area of new bone formation within the CSD. Results: Comparing four groups, results were obtained as follows. 1. In non-ovariectomized groups, PRP showed a positive effect somewhat but not significant (P > .05). 2. In ovariectomized groups, PRP showed a positive effect significantly (P < .05). 3. In PRP untreated groups, ovariectomy diminished bone regeneration significantly (P < .05). 4. In PRP treated groups, ovariectomy diminished bone regeneration somewhat but not significant (P > .05). Conclusion: Within the limitation of this study, it can be concluded that PRP in combination with an osteoconductive synthetic alloplastic substitute has an effect on bone regeneration more significantly in ovariectomized osteoporotic rats than in normal rats.

• Clinical and Experimental Reproductive Medicine
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• v.50 no.4
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• pp.285-291
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• 2023

Objective: Infertility can result from a diminished ovarian reserve, but a potential remedy exists in the form of platelet-rich plasma (PRP) administration. This treatment involves both biological factors and tissue trauma mechanisms, which stimulate folliculogenesis, making it a promising and effective strategy. We assessed the impact of direct PRP injections into the ovaries on the fertility outcomes of women classified as poor responders. Methods: A quasi-experimental study was conducted from April 2021 to December 2022, focusing on patients classified as POSEIDON grade 3 or 4. PRP injections were administered into both ovaries. After 3 months, data were collected on anti-Mullerian hormone (AMH) level, follicle-stimulating hormone (FSH) level, and the numbers of oocytes, mature oocytes, and good-quality embryos following ovarian stimulation. We then compared the data from before and after PRP injection. Results: This study included 50 women, with a mean of 39 years (interquartile range [IQR], 35 to 43) and 4 years (IQR, 2 to 6) for age and infertility duration, respectively. FSH levels decreased after treatment, while AMH levels and the numbers of oocytes, metaphase II oocytes, and high-quality embryos increased. However, only the increase in high-quality embryos was significant. The pregnancy and spontaneous pregnancy rates were 20% and 14%, respectively. Notably, women with secondary infertility exhibited a significantly higher pregnancy rate than those with primary infertility. Conclusion: Ample evidence suggests that PRP can enhance ovarian function. However, further studies are needed to identify the appropriate candidates for this procedure, establish the optimal PRP preparation method, and standardize the procedure for its adjuvant use in assisted reproductive technology cycles.

• Journal of Life Science
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• v.28 no.4
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• pp.398-407
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• 2018

The Purple pericarp (Prp) trait is a trait often bred for in black rice. Generally, the Prp trait is displayed in the color variations of seeds following the 9:3:4 purple, brown, and white ratio, respectively. The Prp trait is a recessive epistasis of two gene interactions; however, it is caused by the two complementation genes Pb and Pp. Here we present a study of the genetic characteristics of the Prp trait using an $F_1$ hybrid with a Pbpb Pppp genotype. This hybrid generated four seed colors with the following numbers: 3 dark purple, 6 medium purple, 3 brown, and 4 white (or 9 purple, 3 brown, and 4 white). However, further biochemical analysis of the all progenies divided them into two groups. One group had the Pb_ Pp_ allelic constitutions and contained cyanidin 3-O-glucoside (C3G) in both the dark purple or medium purple seeds. The other group, however, was absent of C3G in both the brown and white seeds, resulting in a ratio of 9:7, respectively. This segregation revealed the extended Mendelian 9:7 ratios of the complementary gene interactions with a good fitness in ${\chi}^2$ analysis. Further analysis revealed that brown seeds with the Pb_ pppp genotype corresponded with a null C3G, indicating that the Brown pericarp trait in rice is caused by a dominant allele of the Pb gene. Therefore, we conclude that the production of C3G is a main phenotype of the black and purple colored rice in the Prp trait, and it is governed by the complementary gene interactions between Pb and Pp genes.

• Archives of Plastic Surgery
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• v.40 no.5
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• pp.530-535
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• 2013

Background Platelet-rich plasma (PRP) has more concentrated platelets than normal plasma (approximately 150-400${\times}10^3$ cell/dL). Platelets excrete several growth factors and cytokines that are associated with the healing and regeneration process. However, even though PRP is widely used, the mechanism or actual effect is presently unclear. Therefore, this study was performed to investigate the levels of growth factors and platelet concentration rate. Methods Autologous blood for preparing PRP was obtained from healthy subjects aged 25 to 35 years. The samples were divided into 4 experimental groups (inactivated whole blood, inactivated PRP, activated whole blood with thrombin and calcium chloride, and activated PRP). The platelet counts in the blood were analyzed and the growth factors were quantitatively measured. A statistical analysis was performed by using Dunn's multiple comparison test. Results In the blood cell analysis, the platelet count of the PRP group was approximately 4.25 times higher than that of the whole blood group. In the quantitative analysis of growth factors, the platelet-derived growth factor (PDGF)-AB, PDGF-BB, and transforming growth factor-${\beta}$ of the inactivated and activated PRP groups were higher than those of the inactivated and activated whole blood groups (P<0.05). Conclusions In this study, the platelet count and the levels of PDGF-AB and PDGF-BB in the PRP were determined. Further, more research is required on the bioactivity level of the growth factors secreted during the process of PRP preparation and the potency of growth factors that can be exerted physiologically in vivo.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.647-653
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• 2014

Background Administration of growth factors has been associated with increased viability of composite grafts greater than 1-cm in diameter. Platelet-rich plasma (PRP) contains many of the growth factors studied. In this study, we evaluate the effect of PRP injection on composite graft viability and the proper time for injection. Methods A total of 24 New Zealand White rabbits were divided into four groups. Autologous PRP was injected into the recipient sites three days before grafting in group 1, on the day of grafting in group 2, and three days after grafting in group 3. Group 4 served as control without PRP administration. Auricular composite grafts of 3-cm diameter were harvested and grafted back into place after being rotated 180 degrees. Median graft viability and microvessel density were evaluated at day 21 of graft via macroscopic photographs and immunofluorescent staining, respectively. Results The median graft survival rate was 97.8% in group 1, 69.2% in group 2, 55.7% in group 3, and 40.8% in the control group. The median vessel counts were 34 (per ${\times}200$ HPF) in group 1, 24.5 in group 2, 19.5 in group 3, and 10.5 in the control group. Conclusions This study demonstrates that PRP administration is associated with increased composite graft viability. All experimental groups showed a significantly higher survival rate and microvessel density, compared with the control group. Pre-administration of PRP was followed by the highest graft survival rate and revascularization. PRP treatments are minimally invasive, fast, easily applicable, and inexpensive, and offer a potential clinical pathway to larger composite grafts.