• Molecules and Cells
• /
• 제43권7호
• /
• pp.662-670
• /
• 2020

We have investigated the involvement of the pre-mRNA processing factor 4B (PRP4) kinase domain in mediating drug resistance. HCT116 cells were treated with curcumin, and apoptosis was assessed based on flow cytometry and the generation of reactive oxygen species (ROS). Cells were then transfected with PRP4 or pre-mRNA-processing-splicing factor 8 (PRP8), and drug resistance was analyzed both in vitro and in vivo. Furthermore, we deleted the kinase domain in PRP4 using Gateway™ technology. Curcumin induced cell death through the production of ROS and decreased the activation of survival signals, but PRP4 overexpression reversed the curcumin-induced oxidative stress and apoptosis. PRP8 failed to reverse the curcumin-induced apoptosis in the HCT116 colon cancer cell line. In xenograft mouse model experiments, curcumin effectively reduced tumour size whereas PRP4 conferred resistance to curcumin, which was evident from increasing tumour size, while PRP8 failed to regulate the curcumin action. PRP4 overexpression altered the morphology, rearranged the actin cytoskeleton, triggered epithelial-mesenchymal transition (EMT), and decreased the invasiveness of HCT116 cells. The loss of E-cadherin, a hallmark of EMT, was observed in HCT116 cells overexpressing PRP4. Moreover, we observed that the EMT-inducing potential of PRP4 was aborted after the deletion of its kinase domain. Collectively, our investigations suggest that the PRP4 kinase domain is responsible for promoting drug resistance to curcumin by inducing EMT. Further evaluation of PRP4-induced inhibition of cell death and PRP4 kinase domain interactions with various other proteins might lead to the development of novel approaches for overcoming drug resistance in patients with colon cancer.

• Pediatric Infection and Vaccine
• /
• 제10권1호
• /
• pp.71-80
• /
• 2003

목 적 : b형 Haemophilus influenzae(Hib)의 피막 다당질인 polyribosyl -ribitol-phosphate(PRP)가 Hib 질환의 발병기전에 중요한 역할을 하며, 이에 대한 항체가 있으면 Hib 질환을 예방할 수 있다. Hib 질환을 예방하기 위해 개발된 단백 결합 백신에는 PRP-D, PRP-T, PRP-OMP 및 PRP-CRM197 등이 있다. Hib 피막 다당질에 대한 항체 반응은 백신에 사용된 결합 단백의 종류에 따라 다르지만 인종이나 제조 회사에 따라서 유효성 및 안전성에 차이가 있을 수 있다. PRP-T에는 기존에 국내에 공급되던 $ActHib^{(R)}$(Aventis)와 최근에 국내에 도입되기 시작한 $Hiberix^{TM}$(GlaxoSmithKline Biologicals)가 있다. 본 연구에서는 우리나라 영아에서 PRP-T 백신인 $Hiberix^{TM}$의 면역원성 및 안전성을 평가하고자 하였다. 방 법 : 2001년 3월부터 2002년 4월까지 소아과에 예방접종을 위해 내원한 건강한 생후 2개월 이상의 영아 73명(남아 43명)을 대상으로 하였다. 생후 2, 4, 6개월에 PRP-T 백신($Hiberix^{TM}$)을 필요한 경우에 DTaP, TOPV, B형 간염백신과 같이 접종하였고, 1회 접종 전(2개월), 2회 접종 2개월 후(생후 6개월) 그리고 3회 접종 1개월 후(생후 7개월)에 혈청내 항 PRP 항체가를 효소면역법(ELISA)으로 측정하였다. 매 접종 후 72시간내에 발생하는 국소적, 전신적 이상반응을 관찰하였다. 면역원성은 계획한대로 접종을 완료한 영아에 대하여 분석하였으며, 이상반응은 1회 이상 접종받은 모든 영아에 대하여 분석하였다. 결 과 : 73명 중 63명(남아 37명)이 계획한대로 접종을 완료하였다. 생후 2개월에 측정한 접종 전항 PRP 항체가의 기하 평균치는 0.17 ${\mu}g/mL$(95% CI; 0.13~0.22)이었다. 2회 접종 후(생후 6개월) 항체가의 기하 평균치는 4.14 ${\mu}g/mL$(95% CI; 2.65~6.48), 3회 접종 후(생후 7개월)의 기하 평균치는 14.65 ${\mu}g/mL$(95% CI; 10.83~19.81)이었다. 항체가가 1.0 ${\mu}g/mL$ 이상인 비율은 2회 접종 후 77.8% (95% CI; 67.5~88.0), 3회 접종 후 98.4%(95% CI;95.3~100)이었다. 백신 접종 후 발생한 이상반응중 전신반응으로서 보챔(45.5%)이 가장 많았고 졸음(30.5%), 수유감소(26.7%), 발열(5.6%) 순이었다. 국소반응으로서 동통이 7.9%, 발적(${\geq}5$ mm) 2.8%, 부종(${\geq}5$ mm) 1.8% 순이었다. 이러한 이상반응은 대부분 경증으로 모두 회복되었다. 결 론 : 결론적으로, PRP-T 백신인 $Hiberix^{TM}$는 우리나라 영아에서 우수한 면역원성과 안전성을 보였으며, 특히 2회 접종으로도 항체가의 기하 평균치가 장기적인 방어 수준으로 상승함은 과거의 다른 PRP-T 백신($ActHib^{(R)}$)의 연구 결과들과 일치하는 소견으로 향후 국내에서 PRP-T 백신의 접종 방법에 대한 재고가 필요하다고 사료된다.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제29권2호
• /
• pp.113-122
• /
• 2007

Purpose: Platelet-rich plasma (PRP) is known to accelerate and/or enhance hard and soft tissue healing and regeneration. As such, PRP has been used in various clinical fields of surgery. Recently there have been several attempts to use PRP in the field of tissue engineering. However, some controversies still exist on exact mechanism and benefits of PRP. Therefore various animal experiments are necessary to reveal the effect of the PRP. However, even if animal experiment is performed, the efficacy of the experiment could not be validated due to absence of an animal PRP model. The purpose of this study is to establish rat PRP model by comparing several PRP fabricating methods, and to assay growth factor concentration in the PRP. Materials and methods: Rat blood samples were collected from nine SD rat (body weight: 600-800g). PRP was prepared using three different PRP fabricating methods according to previously reported literatures. (Method 1: 800 rpm, 15 minute, single centrifuge; Method 2: 1000 rpm, 10 minute, double centrifuge; Method 3: 3000 rpm, 4min and 2500 rpm, 8 min, double centrifuge). Platelet counts were evaluated in an automated machine before and after PRP fabrications. In terms of growth factor assay, prepared PRP were activated with 100 unit thrombin and 10% calcium chloride. Growth factor (PDGF-BB, VEGF) concentrations on incubation time were determined by sandwich-ELISA technique. Results: An average of 3ml (via infraorbital venous plexus) to 15ml (via celiac axis) the rat blood could be collected. By using Method 3 (3000 rpm, 4 min and 2500 rpm, 8 min, double centrifugation), around 1.5ml of PRP could be prepared. This method allowed us to concentrate platelet 3.77-fold on average. PDGF-BB concentration (mean, 1942.10 pg/ml after 1 hour incubation) and VEGF concentration (mean, 952.71 pg/ml after 1 hour incubation) in activated PRP were higher than those in untreated blood. Also PDGF-BB showed constant concentration during 4-hour incubation, while VEGF concentration was decreased after 1 hour. Conclusion: Total 11,000 g minute separation and condensation double centrifuge method can produce efficient platelet-rich plasma. Platelet-rich plasma activated with thrombin has showed higher concentrations of growth factors such as PDGF-BB and VEGF, compared to the control group. Platelet-rich plasma model in a rat model was confirmed in this study.

• Journal of Periodontal and Implant Science
• /
• 제31권3호
• /
• pp.513-529
• /
• 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.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제33권3호
• /
• pp.221-226
• /
• 2007

Purpose The purpose of this study is to evaluation of effect on bone formation of PRP and fibrin sealant with deproteinized bovine bone(Bio-Oss) grafts on rabbit cranial defect. Material and Methods Twelve rabbits were used as experimental animal Two equal 9mm diameter cranial bone defects were created in each rabbit and immediately grafted with Bio-Oss only, Bio-Oss and PRP, and Bio-Oss and Fibrin sealant. Rabbits were sacrificed at 4 and 8 week. The defects were evaluated by histomorphometric analysis. Results Kruskal-Wallis tests were performed comparing new bone formation via histomorphometric analysis. No statistically significant difference of new bone formation was found between Bio-Oss only, Bio-Oss and PRP, and Bio-Oss and fibrin sealant at 4 and 8 weeks (P>0.05). Conclusion This study fails to find a stimulatory effect of PRP and Fibrin sealant on New bone formation of Bio-Oss grafts by histomorphometric analyses.

• 대한치과보철학회지
• /
• 제39권6호
• /
• pp.659-681
• /
• 2001

Platelet-rich plasma(PRP) has been known to increase the rate and degree of bone formation by virtue of growth factors in concentrated platelets. Although its great healing effect on bone defect or pre-implantation site preparation in conjunction with bone substitute has been reported, the effect associated with implant is unknown. The purpose of this study was to investigate the effect of PRP on rapid osseointegration of endosseous dental implants in the rabbit tibiae. Twenty two adult female New Zealand white rabbits, weighing approximately 2.7-3.3kg, were used for this study. Twelve of the 22 animals were used for histomorphometric analysis and ten of the 22 were for removal torque test. Each animal received two implants in each tibia (two treated with PRP and two as control) and was given fluorochrome intramuscularly. For histomorphometric analysis, rabbits were divided into four groups according to the healing period. At 1 week, 2 weeks, 4 weeks and 8 weeks postoperatively, each three animals were sacrificed serially and the amount and rate of bone formation around dental implant were examined on the undecalcified sections under fluorescent microscope, polarized microscope and light microscope connected to a personal computer equipped with image analysis system. For removal torque test, rabbits were divided into two groups and removal torque tests were performed at 4 weeks, 10 weeks after implant placement. In total, 88 screw shaped, commercially pure titanium implants (Neoplant, Neobiotech, Seoul, Korea) were used in this study. Labeling pattern reflected differences of two groups in bone formation rate at each period. Histomorphometrically, PRP group showed significantly higher bone volume within threads compared to control group at 2 weeks ($70.30{\pm}4.96%$ vs. $50.68{\pm}6.33%$; P < .01) and 4 weeks ($82.59{\pm}5.94%$ vs. $72.94{\pm}4.57%$; P < .05 ). PRP group at 1, 2 and 4 weeks revealed similar degree of bone volume formation comparable to control group at 2, 4 and 8 weeks, respectively. On the other hand, while PRP group showed higher bone-implant contact ($47.37{\pm}8.09%$) than control group ($33.16{\pm}13.47%$) at 2 weeks, there were no significant differences between PRP group and control group for any experimental period. Removal torque values also showed no significant differences between PRP group and control group at any experimental period (P > .05). These findings imply that PRP could induce rapid, more bone formation around implant during early healing period and get faster secondary stability for reducing healing period, though it has not induced bone maturation enough to resist functional loading.

• Clinics in Shoulder and Elbow
• /
• 제25권1호
• /
• pp.73-89
• /
• 2022

Background: To evaluate the efficacy of autologous platelet-rich plasma (PRP) injections in the treatment of common shoulder diseases. Methods: The PubMed, Medline, and Central databases and trial registries were searched from their inception to October 2020 for randomized controlled trials of autologous PRP injections for shoulder diseases versus placebo or any control intervention. Preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed in the selection, analysis, and reporting of findings. The primary outcome was pain intensity (visual analog scale), and secondary outcomes were changes in function and quality of life (QoL). Results: A total of 17 randomized controlled trials of PRP versus control were analyzed. From 8-12 weeks to ≥1 year, PRP injections were associated with better pain relief and functional outcomes than control interventions. PRP injections were also associated with greater QoL, with an effect size of 2.61 (95% confidence interval, 2.01-14.17) at medium-term follow-up. Compared with placebo and corticosteroid injections, PRP injections provided better pain relief and functional improvement. In subgroup analyses, trials in which PRP was prepared by the double centrifugation technique, the platelet concentration in the PRP was enriched ≥5 times, leucocyte-rich PRP was used, or an activating agent was used before application reported the most effective pain relief at 6-7 months. Conclusions: PRP injections could provide better pain relief and functional outcomes than other treatments for persons presenting with common shoulder diseases. PRP injections have a greater capacity to improve shoulder-related QoL than other interventions.

• Archives of Plastic Surgery
• /
• 제34권3호
• /
• pp.291-297
• /
• 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.

• Journal of Veterinary Science
• /
• 제25권2호
• /
• pp.22.1-22.15
• /
• 2024

Background: Achilles tendon is composed of dense connective tissue and is one of the largest tendons in the body. In veterinary medicine, acute ruptures are associated with impact injury or sharp trauma. Healing of the ruptured tendon is challenging because of poor blood and nerve supply as well as the residual cell population. Platelet-rich plasma (PRP) contains numerous bioactive agents and growth factors and has been utilized to promote healing in bone, soft tissue, and tendons. Objective: The purpose of this study was to evaluate the healing effect of PRP injected into the surrounding fascia of the Achilles tendon after allograft in rabbits. Methods: Donor rabbits (n = 8) were anesthetized and 16 lateral gastrocnemius tendons were fully transected bilaterally. Transected tendons were decellularized and stored at -80℃ prior to allograft. The allograft was placed on the partially transected medial gastrocnemius tendon in the left hindlimb of 16 rabbits. The allograft PRP group (n = 8) had 0.3 mL of PRP administered in the tendon and the allograft control group (n = 8) did not receive any treatment. After 8 weeks, rabbits were euthanatized and allograft tendons were transected for macroscopic, biomechanical, and histological assessment. Results: The allograft PRP group exhibited superior macroscopic assessment scores, greater tensile strength, and a histologically enhanced healing process compared to those in the allograft control group. Conclusions: Our results suggest administration of PRP on an allograft tendon has a positive effect on the healing process in a ruptured Achilles tendon.

• 대한골관절종양학회지
• /
• 제16권1호
• /
• pp.8-13
• /
• 2010

목적: 양성 골종양의 소파수술 후 발생한 골 결손에 대해 동종골 이식시 골 유합을 촉진시키기 위해 자가 혈소판 풍부 혈장(Platelet-Rich Plasma)를 주입한 후 골 유합 시기를 비교하여 골 치유 과정에 대한 효과를 알아보고자 하였다. 대상 및 방법: 2007년 12월부터 2009년 2월까지 양성 골종양 환자 중 병소의 소파술 실시 후 동종골을 이식한 환자 중 12개월 이상 추시 관찰(평균 추시 기간 14.6개월, 12-26개월)이 가능하였던 총 21예(남자 12명, 여자 9명)를 대상으로 하였으며 자가골과 함께 동종골 이식을 실시한 환자는 배제하였다. 동종골 이식시 자가 혈소판 풍부 혈장을 주입한 13예와 동종골 이식만을 실시한 8예에서 수술 전후 단순 방사선 소견상 병소 크기, 골 유합 시기, 자가 혈소판 풍부 혈장의 투여량, 합병증 등을 살펴보았다. 대상 환자의 수술 시 나이는 평균 23.6세였으며(4-73세), 원인 질환은 단순 골 낭종 7예, 골내연골종 4예, 거대 세포종 3예, 분류 미상의 양성 골종양 3예, 섬유성 이형성증 1예, 비골화성 섬유종 1예, 골내 지방종 1예, 동맥류성 골 낭종을 동반한 단순 골 낭종 1예이었다. 결과: 방사선 사진 상 술 전 병소의 부피는 평균 33.5 $cm^3$ (2.3-181.9 $cm^3$)이었으며 자가 혈소판 풍부 혈장을 투여한 집단은 평균 29.4 $cm^3$, 자가 혈소판 풍부 혈장 없이 동종골 이식만을 실시한 집단은 평균 40.2 $cm^3$였다. 동종골 이식술과 함께 자가 혈소판 풍부 혈장을 투여한 집단에서 자가 혈소판 풍부 혈장의 평균 투여량은 7.4 cc (3-12 cc)이었으며, 골유합은 술 후 평균 3.0개월(1.5-5.8개월)에 이루어졌으며 동종골 이식술만을 실시한 집단에서는 술 후 평균 5.3개월(4-8개월)에 이루어졌다. 이 중 각각 3예에서 병변의 재발, 병적 골절 등이 발생하여 제외하였는데 자가 혈소판 풍부 혈장을 투여한 집단에서는 2예에서 병변이 재발하였으며 1예에서 불유합으로 인한 골절이 나타났고, 혈소판 풍부 혈장을 투여하지 않은 집단에서는 2예에서 병변이 재발하였고 1예에서 골절이 나타났다. 혈소판 풍부 혈장 투여의 합병증으로 술 후 3주 째에 발열이 있었으나 이는 항생제 경구 투여로 호전되었다. 결론: 양성 골종양의 소파술 후 발생한 골 결손에 대해 실시한 동종골 이식시 자가 혈소판 풍부 혈장을 투여하여 골 유합을 촉진시킬 수 있으며 나아가 골절, 불유합 등에서도 동종골 이식시 자가 혈소판 풍부 혈장을 투여하여 골 유합을 촉진시킬 수 있을 것으로 기대된다.