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Clinical Scenario: Ankle sprains are one of the most common injuries in athletics, and many lead to recurrent sprains, chronic ankle instability, and persistent symptoms. Treatment improvements are needed. Platelet-rich plasma (PRP) involves formulating autologous plasma with higher platelet concentration to be injected in the desired tissue. There is currently high-quality evidence supporting the use of PRP with lateral epicondylitis and knee osteoarthritis to accelerate the healing process and decrease pain. Clinical Question: Does the injection of PRP relieve pain faster and improve function compared with no injection or placebo in patients with a lateral ankle sprain? Summary of Key Findings: A computerized search yielded 191 studies; of these, 3 studies fit the inclusion and exclusion criteria. PRP injection reduces pain and increases function after lateral ankle sprain 5 to 8 weeks after intervention. Clinical Bottom Line: The use of PRP after lateral ankle sprain to decrease pain and increase function is supported with moderate evidence. Strength of Recommendation: Based on the Strength of Recommendation Taxonomy, evidence from the included studies is considered as level B, reflecting limited quality patient-oriented evidence. [ABSTRACT FROM AUTHOR]

Purpose: To answer the following question: "Do recombinant, purified, and concentrated growth factors enhance the regenerative potential of particulate bone graft substitutes in maxillary sinus floor augmentation (MSA)" Materials and Methods: Human studies comparing histomorphometric data on new bone formation, residual graft material, and fibrous tissue ratio (outcomes of interest) following MSA procedures employing particulate bone grafts/substitutes in combination or not with growth factors were retrieved from PubMed/MEDLINE, Web of Science, Cochrane, and Scopus online databases and complemented with a hand search. Controlled studies published in English up to December 2022 and reporting on histomorphometric data expressed as volume percentage of the outcomes of interest were considered. Risk of bias was assessed, and a meta-analysis was performed to investigate the effects of supplementary growth factors on new bone formation, remaining graft particles, and fibrous tissue ratio. Results: Data were included from 613 samples in 477 patients reported in 22 publications. Meta-analysis showed that platelet-rich plasma or platelet-rich fibrin resulted in 49% more new bone formation than in control group areas (P = .004), and those areas supplemented with growth factors presented 57% less residual graft particles after healing (P < .0001). A significant (P = .03) 1.85-fold increase in connective tissue formation was noted in areas treated with recombinant human bone morphogenetic proteins (rhBMPs) after healing. Conclusions: Selective supplementary growth factors may enhance new bone formation and accelerate particulate graft turnover, while rhBMP may significantly increase connective tissue formation in MSA procedures in humans. [ABSTRACT FROM AUTHOR]

Objectives: This case series aimed to assess the efficacy of a novel horizontal ridge augmentation modality using histology. Combinations of "sticky bone" and tenting screws without autologous bone were used as augmentative materials. Method and materials: Five individuals presenting healed, atrophic, partially edentulous sites that required horizontal bone augmentation before implant placement were enrolled. Patients underwent the same augmentation type and 5 months of postoperative reentry procedures. The first surgery served as implant site development, whereas the biopsy and corresponding implant placement were performed during reentry. The bone was qualitatively analyzed using histology and histomorphometry and quantitatively evaluated using CBCT. Results: Four individuals healed uneventfully. Early wound dehiscence occurred in one case. Histology showed favorable bone substitute incorporation into the newly formed bone and intimate contact between de novo bone and graft material in most cases. Histomorphometry revealed an average of 48 ± 28% newly formed bone, 19 ± 13% graft material, and 33 ± 26% soft tissue components. The CBCTbased mean alveolar ridge horizontal increase was 3.9 ± 0.6 mm at 5 months postoperatively. Conclusions: The described augmentation method appears suitable for implant site development resulting in favorable bone quality according to histology. However, clinicians must accommodate 1 to 2 mm of resorption in augmentative material width at the buccal aspect. [ABSTRACT FROM AUTHOR]

The document explores the use of digital and manual techniques to restore severe atrophy in the esthetic zone, particularly in cases of facial lesions requiring surgical resection. It recommends the use of zygomatic implants combined with conventional implants for atrophic jaws and oncologic rehabilitation. A detailed case study of a patient with an ameloblastoma in the left maxilla illustrates the restoration process involving ceramics and zirconia frameworks. The document "Casos Clínicos y de Laboratorio. Actualidades Médico Odontológicas Latinoamérica, 2004" contains a series of articles on various topics related to dental prosthetics and restorations, including prosthetic gingival reconstruction, bonding zirconia, and clinical evaluation of zirconia abutments for implant-supported restorations. [Extracted from the article]

PurposeWe evaluate the efficacy and safety profiles of currently available conservative management options for penile and urethral lichen sclerosus.Materials and methodsA systematic review of existing literature on lichen sclerosus was conducted utilizing the PubMed, Embase, and Web of Science databases. References were assessed for relevance to nonsurgical management of male genital lichen sclerosus by title and abstract by 3 independent reviewers, then reviewed in full and in duplicate by 5 independent reviewers.ResultsSeventeen studies describing conservative management of histologically confirmed penile and urethral lichen sclerosus in male patients were included in the final review. We present available evidence supporting the use of 4 major treatment modalities represented in the existing literature: topical corticosteroids, tacrolimus, platelet-rich plasma, and CO2 laser. We also briefly discuss the limited studies on the use of oral acitretin and polydeoxyribonucleotide injections. Outcomes assessed include symptoms, clinical appearance, quality of life, sexual satisfaction, adverse effects, and long-term efficacy of treatment.ConclusionsTopical corticosteroids remain the mainstay of conservative management of penile and urethral lichen sclerosus, with current literature supporting the use of other therapies such as tacrolimus and platelet-rich plasma as alternatives or adjuvant treatments when escalation of treatment is necessary. Future research should further explore the efficacy and safety of newer therapies through additional controlled clinical trials in the targeted population.

BACKGROUND: Flap transplantation technique is a commonly used surgical procedure for the treatment of severe tissue defects, but postoperative flap necrosis is easily triggered by ischemia-reperfusion injury. Therefore, it is still an important research topic to improve the survival rate of transplanted flaps. OBJECTIVE: To review the pathogenesis and latest treatment progress of flap ischemia-reperfusion injury. METHODS: CNKI, WanFang Database and PubMed database were searched for relevant literature published from 2014 to 2024. The search terms used were “flap, ischemia-reperfusion injury, inflammatory response, oxidative stress, Ca2+ overload, apoptosis, mesenchymal stem cells, platelet-rich plasma, signaling pathways, shock wave, pretreatment” in Chinese and English. After elimination of irrelevant literature, poor quality and obsolete literature, 77 documents were finally included for review. RESULTS AND CONCLUSION: Flap ischemia/reperfusion injury may be related to pathological factors such as inflammatory response, oxidative stress response, Ca2+ overload, and apoptosis, which can cause apoptosis of vascular endothelial cells, vascular damage and microcirculation disorders in the flap, and eventually lead to flap necrosis. Studies have found that mesenchymal stem cell transplantation, platelet-rich plasma, signaling pathway modulators, shock waves, and pretreatment can alleviate flap ischemia/reperfusion injuries from different aspects and to varying degrees, and reduce the necrosis rate and necrosis area of the grafted flap. Although there are many therapeutic methods for skin flap ischemia/reperfusion injury, a unified and effective therapeutic method has not yet been developed in the clinic, and the advantages and disadvantages of various therapeutic methods have not yet been compared. Most of the studies remain in the stage of animal experiments, rarely involving clinical observations. Therefore, a lot of research is required in the future to gradually move from animal experiments to the clinic in order to better serve the clinic. [ABSTRACT FROM AUTHOR]

This study is to summarize and evaluate the available evidence for the efficacy of platelet-rich plasma (PRP) and hyaluronic acid (HA) for knee osteoarthritis (KOA). Eight databases were searched from inception to September 15, 2024. All systematic reviews (SRs)/meta-analyses (MAs) treated with PRP versus HA for KOA were collected. Literature screening and data extraction were independently performed by two reviewers. The methodological quality, reporting quality, risk of bias, evidence quality, and evidence overlap rate of the included studies were evaluated by using AMSTAR 2, PRISMA 2020, ROBIS, GRADE, and GROOVE systems. Seventeen SRs were included. The results showed that the effectiveness and safety of PRP in the treatment of KOA may be superior to HA. The methodological quality of all 17 documents was extremely low quality. Sixteen of them had poor reporting quality, and there were relatively serious information deficiencies. All SRs were determined to be at high risk. Among the 221 outcome indicators, there were two medium-quality evidences, 30 low-quality evidences, and 189 extremely low-quality evidences. It was found that there was a very high overlap among the included articles. Currently, the quality of SRs on the treatment of KOA with PRP versus HA is relatively low. Future authors of SRs should adhere to quality assessment tool criteria, expand sample sizes to reduce overlap, and evaluate the quality of evidence for merged study results, in order to provide more reliable and rigorous evidence-based support for clinical practice. [ABSTRACT FROM AUTHOR]

Sciatic nerve damage, a common condition affecting approximately 2.8% of the US population, can lead to significant disability due to impaired nerve signal transmission, resulting in loss of sensation and motor function in the lower extremities. In this study, a neural guidance channel was developed by rolling a nanofibrous scaffold produced via electrospinning. The scaffold's microstructure, biocompatibility, biodegradation rate, porosity, mechanical properties, and hemocompatibility were evaluated. Platelet-rich plasma (PRP) activated with 30,000 allogeneic Schwann cells (SCs) was injected into the lumen of the channels following implantation into a rat model of sciatic nerve injury. Recovery of motor function, sensory function, and muscle re-innervation was assessed using the sciatic function index (SFI), hot plate latency time, and gastrocnemius muscle wet weight loss. Results showed mean hot plate latency times of Autograft: 7.03, PCL/collagen scaffolds loaded with PRP and SCs (PCLCOLPRPSCs): 8.34, polymer-only scaffolds (PCLCOL): 10.66, and untreated animals (Negative Control): 12.00. The mean SFI values at week eight were Autograft: −49.30, PCLCOLPRPSCs: −64.29, PCLCOL: −75.62, and Negative Control: −77.14. The PCLCOLPRPSCs group showed a more negative SFI compared to the Autograft group but performed better than both the PCLCOL and Negative Control groups. These findings suggest that the developed strategy enhanced sensory and functional recovery compared to the negative control and polymer-only scaffold groups. [ABSTRACT FROM AUTHOR]

Purpose: Chronic whiplash-associated disorders (WAD) is a heterogeneous condition with limited effective treatment options available. This study evaluated the efficacy of multimodal physiotherapy and usual care in chronic WAD with facet-mediated pain receiving platelet-rich plasma (PRP) injections to determine if pain interference and confidence completing activities in the presence of neck pain could be improved. Materials and methods: A multiple-baseline, single-case experimental design was used to evaluate the 6-week effect of physiotherapy or usual care in two groups of three participants each. Results: All six participants demonstrated a significant reduction in pain interference, and three participants showed improved confidence to perform daily activities when in pain. Weighted Tau-U demonstrated a significant reduction of pain interference with large to very large effect sizes (> 0.75) for both interventions in all participants irrespective of treatment allocation with no significant group difference demonstrated. Similar effects were demonstrated for the confidence to perform daily activities with neck pain (ES > 0.46), although this was only evident in three participants (two PT and one UC). Generalisation measures also showed improvements in pain and disability, psychological and quality of life outcomes. No adverse events were reported. Conclusions: Both physiotherapy and usual care demonstrated improvements in pain interference and confidence to perform activities of daily living with neck pain in people with chronic WAD following cervical facet joint PRP. Trial Registration: The trial was registered with ClinicalTrials.gov (Protocol Number: NCT03949959). [ABSTRACT FROM AUTHOR]

Background: Herpes zoster (HZ), triggered by the reactivation of the varicella-zoster virus, manifests as a painful rash known as zoster-associated pain (ZAP), which can progress to postherpetic neuralgia (PHN). This study evaluates the efficacy and safety of ultrasound-guided thoracic paravertebral injections of platelet-rich plasma (PRP) in managing acute ZAP and preventing PHN. Methods: This is a prospective, randomized, controlled, open-label, endpoint-blinded, single-center trial involving 128 participants suffering from zoster-associated pain. Participants will be randomly assigned to the PRP treatment in combination with antiviral therapy group or the antiviral therapy group at a 1:1 ratio. Pain intensity (NRS-11), quality of life (SF-12), sleep quality (PSQI), pain characteristics, skin lesion recovery, average weekly consumption of rescue analgesics, and adverse events will be assessed. Follow-up assessments will be conducted at 1, 3, 6, and 12 months post-intervention to evaluate the incidence rate of PHN, pain intensity, quality of life, sleep quality, and safety. Ethics and Dissemination: Adhering to the 2013 SPIRIT statement and the Declaration of Helsinki, this study has received ethical approval from the relevant committee. Results will be disseminated through scientific journals and conferences, contributing to global data on managing ZAP. Conclusions: By comparing PRP with antiviral therapy, this trial seeks to establish a more effective treatment paradigm for reducing acute zoster-associated pain and the incidence of PHN, potentially setting a new standard in therapeutic strategies for HZ. Trial Registration: This clinical trial is registered with the Chinese Clinical Trial Registry (ChiCTR) at https://www.chictr.org.cn/index.html (Registration Number: ChiCTR2400087248, Registration Date: 2024–07-23). [ABSTRACT FROM AUTHOR]

Platelet-rich plasma has been increasingly used for facial rejuvenation in conjunction with other modalities such as microneedling or on its own. Nanofat grafting to the face has also been utilized for skin quality improvements. Our group previously described the novel combined Platelet Hybridized Adipose Transplant (PHAT) technique for hair restoration. In this series, we describe our experience with the PHAT technique for lip and facial rejuvenation to improve the quality of facial skin and superficial musculoaponeurotic system, and enhancing surgical results. [ABSTRACT FROM AUTHOR]

BACKGROUND: During healing process of chronic wounds, excessive production of reactive oxygen species can impair the function of L929 fibroblasts, thereby delaying wound repair. Therefore, protecting fibroblasts from oxidative stress is important to promote wound healing. OBJECTIVE: To assess the protective effects of carboxymethyl chitosan-oxidized chondroitin sulfate/platelet-rich plasma (CMC-OCS/PRP) hydrogel on L929 cells under H2O2 stimulation. METHODS: CMC-OCS/PRP hydrogels were prepared, and the micromorphology, degradation performance, scavenging ability of H2O2 and hydroxyl radical and biocompatibility of the hydrogels were characterized. L929 cells with good growth state were taken and cultured in five groups. The control group was cultured conventionally. H2O2 was added to the H2O2 group. Carboxymethyl chitosan-oxidized chondroitin sulfate hydrogel extract + H2O2 was added to the CMC- OCS group. Platelet-rich plasma gel extract + H2O2 was added to the PRP group. The CMC-OCS/PRP group was treated with carboxymethyl chitosan-oxidized chondroitin sulfate/platelet-rich plasma hydrogel extract + H2O2. Each group was treated with hydrogel extract for 6 hours, and then H2O2 for 24 hours. After culture, the levels of active oxygen and malondialdehyde, apoptosis and expression of collagen fiber I protein were detected. In the presence of H2O2, the above hydrogel extracts were directly or indirectly co-cultured with L929 fibroblasts for 36 hours, respectively. Migration ability of the cells was detected by scratch test and Transwell chamber test. RESULTS AND CONCLUSION: (1) CMC-OCS/PRP hydrogels had uniform and interrelated porous structure and good degradation ability, could effectively remove H2O2 and hydroxyl radicals in vitro, and had good biocompatibility. (2) Compared with the control group, the apoptosis rate, reactive oxygen species, and malondialdehyde levels were increased (P < 0.05); the spread area of cells was decreased (P < 0.05), and the expression of collagen fiber I protein had no significant changes (P > 0.05) in the H2O2 group. Compared with the H2O2 group, reactive oxygen species level was decreased in the CMC-OCS group (P < 0.05), malondialdehyde level was decreased (P < 0.05), and cell spread area was increased (P <0.05) in the PRP group, CMC-OCS group, and CMC-OCS/PRP group; apoptosis rate was decreased in the CMC-OCS/PRP group (P < 0.05), and collagen fiber I protein expression was increased in the PRP group, CMC-OCS group, and CMC-OCS/PRP group (P < 0.05). (3) Compared with the control group, the number of cell migration was decreased (P < 0.05), and the migration area had no significant change (P > 0.05) in the H2O2 group. Compared with the H2O2 group, the number and area of cell migration were increased in the PRP group, CMC-OCS group, and CMC-OCS/PRP group (P < 0.05), and the increase was most significant in the CMC-OCS/PRP group. (4) Under oxidative stress, CMC-OCS/ PRP hydrogel can improve the migration ability of fibroblasts, resist cell apoptosis, and preserve cell extension function [ABSTRACT FROM AUTHOR]

Introduction and objective: Stress urinary incontinence (SUI) poses a significant burden on affected individuals, impairing their quality of life and causing embarrassment due to involuntary urine leakage during activities such as sneezing or coughing. While conservative and surgical treatments exist, a subset of patients experiences persistent symptoms despite these interventions. This review provides insights into the potential role of platelet-rich plasma (PRP) as a therapeutic adjunct for patients with SUI that does not respond to conventional non-surgical or surgical treatments. Methods: We conducted a literature review of studies in English to evaluate PRP efficacy in managing SUI. Results: The studies conducted on PRP therapy suggest that it is an effective and safe treatment option for SUI in women. PRP injections, when used alone or in combination with other therapies, have shown significant improvements in SUI symptoms. Moreover, these studies indicate that PRP injections offer a less invasive and low-risk alternative to surgical procedures for managing SUI, which could lead to shorter recovery times. Conclusion: The efficacy of PRP therapy is evidenced by significant reductions in SUI symptoms, as well as improvements in bladder function variables, without significant adverse effects reported. However, further research is necessary to establish the long-term effectiveness and safety of PRP therapy for managing SUI in diverse patient populations. Additionally, ongoing evaluations of PRP therapy in combination with other interventions will be essential for optimizing treatment outcomes and broadening the potential applications of PRP in the management of SUI. [ABSTRACT FROM AUTHOR]

Female sexual dysfunction is highly prevalent among postmenopausal females approaching 50%, with vulvovaginal atrophy (VVA) being a cardinal sign. For decades, hormone replacement therapy was the only solution to relieve symptoms associated with this atrophy. However, it was limited by its serious side effects, raising the need for new treatment strategies. This study aims to compare the efficacy and safety of injection of hyaluronic acid (HA) versus platelet rich plasma (PRP) in post-menopausal females presented with VVA to improve female sexual dysfunction. Twenty post-menopausal females presented with VVA were randomly divided into two groups, 10 patients in each group. Both groups received three sessions of injections into the vulva and vagina, one month apart. Group I was injected with non cross linked HA while Group II received PRP injection. Subjective assessment was carried out through female sexual function index questionnaire and global aesthetic improvement scale.While objective assessment was carried out by measuring the labia majora length and reviewing the histopathological changes occurring in the vulva through skin biopsies before and after treatment. The change in vaginal thickness was estimated by transvaginal ultrasound. Results showed that both HA as well as PRP were effective in the treatment of post-menopausal vulvovaginal atrophy. However, HA showed more significant improvement in female sexual dysfunction. There were also higher values in vaginal wall thickness as measured by transvaginal ultrasound in favor of HA injected group. Histopathological assessment showed more collagen deposition in papillary dermis in HA treated group. No complications were reported in both groups. [ABSTRACT FROM AUTHOR]

Objective: To determine whether 448 kHz capacitive-resistive monopolar radiofrequency (CRMR) after platelet-rich-plasma (PRP) injections can further reduce pain sensation within the first 72 h in an active population with patellar chondropathy. Methods: One-hundred fifty-three active patients with patellar chondropathy grade II-III were followed for three days after PRP injections with and without CRMR under a control–placebo study. They were clinically evaluated for pain sensation using a visual analog scale ranging from zero (no pain sensation) to ten (highest pain sensation). Pain sensation was described using medians and analyzed through the Friedman and Conover test for within-group comparison (pre-intervention, and 24, 48, and 72 h post-intervention) and the Mann–Whitney test for between-group comparisons (Intervention vs. Placebo) with α = 5% and 1−β = 80%. Results: The placebo group showed statistical significance between pre-intervention and 24 h (Δ = −2.0 pts, p < 0.001), baseline and 48 h (Δ = −2.0 pts, p < 0.001), baseline and 72 h (Δ = −3.0 pts, p < 0.001), 24 h and 48 h (Δ = 0.0 pts, p < 0.016), and 24 h and 72 h (Δ = −1.0 pts, p < 0.001). The radiofrequency group showed statistical significance between baseline and 24 h (Δ = −7.0 pts, p < 0.001), baseline and 48 h (Δ = −7.0 pts, p < 0.001), baseline and 72 h (Δ = −8.0 pts, p < 0.001), 24 h and 72 h (Δ = −1.0 pts, p < 0.001), and 48 h and 72 h (Δ = −1.0 pts, p < 0.001). The placebo and radiofrequency groups were significantly different at 24 h (Δ = 4.0 pts, p < 0.001), 48 h (Δ = 4.0 pts, p < 0.001), and 72 h (Δ = 4.0 pts, p < 0.001). Conclusions: CRMR therapy administered after knee intra-articular injections of PRP within the first 72 h in active populations with patellar chondropathy reduces pain sensation with a median difference of 8.0 pts compared to baseline and 4.0 pts compared to placebo group. [ABSTRACT FROM AUTHOR]

Background: Lateral elbow tendinopathy is a common condition that significantly alters the function of the upper extremities. In case of first-line treatment failure, different local injections are usually used. Due to the lack of sufficient evidence to support it, we conducted the study to compare the outcomes of different single injections, including Platelet-Rich Plasma (PRP), Corticosteroids (CS), Hyaluronic Acid (HA), and placebo (saline). Methods: Sixty patients with confirmed lateral elbow tendinopathy were enrolled in the study and divided into four groups. Pain intensity (average for the current day, at rest, during provocative tests) measured by Visual Analogue Scale (VAS), pressure pain threshold (PPT), Patient-Rated Tennis Elbow Evaluation (PRTEE), Disability of Arm, Shoulder and Hand (DASH), Subjected Elbow Value (SEV), and strength of selected muscle groups were measured before and during follow-up visits (1, 4, 12, 24, and 52 weeks after treatment). The treatment was considered successful when minimal clinically important difference (MCID) was achieved in primary outcomes (VAS, PRTEE). Results: A significant improvement was achieved in most measurements in all groups. At the final follow-up, MCID for the mean pain reduction measured with VAS and improvement in the PRTEE score were achieved in 52 and 54 patients, respectively. The complete absence of pain was achieved after 1, 4, 12, 24, and 52 weeks in 2, 5, 10, 22, and 40 patients, respectively. The comparison between the groups found a significant difference in pain intensity between CS and other groups one week after injection, between the CS and PRP group in the fourth week, and between PRP and HA in the fourth week (p < 0.05). No other significant differences were found between each group at each follow-up time point. Conclusions: We conclude that each injection treatment provides good long-term clinical outcomes, but not better than placebo. A CS injection might be regarded as a more effective treatment only within the first month post-injection. [ABSTRACT FROM AUTHOR]

Simple Summary: Mesenchymal stromal cells are used for their regenerative properties both in human and veterinary medicine. Usually, these cells are collected from bone marrow or adipose tissue, but methods that allow a simple, economical, and non-invasive collection of cells would encourage their use. One easily accessible alternative source would be urine. In 2008, urine mesenchymal stromal cells were isolated for the first time from human urine. These cells come from the kidney and would, therefore, be ideal for use in the treatment of kidney/genitourinary diseases. In this paper, urine mesenchymal stromal cells were isolated from healthy dogs and dogs affected by chronic kidney disease. Three collection methods (spontaneous micturition, bladder catheterization, and cystocentesis) were compared and cells were analyzed for their mesenchymal properties. The isolated cells met the criteria set by the international society of stem cell therapy to be defined as stem cells. Cells isolated from sick dogs proliferated more readily than those isolated from healthy dogs and may provide a therapeutic option for the treatment of chronic kidney disease. However, in this study, cells could only be isolated from urine samples collected through cystocentesis. Urine-derived mesenchymal stromal/stem cells (USCs) could be a valuable source of cells in regenerative medicine because urine can be easily collected non-invasively. In this paper, USCs were isolated from both healthy dogs and dogs affected by chronic kidney disease (CKD), and the efficacy of collection methods (spontaneous micturition, bladder catheterization, and cystocentesis) were compared. Isolated cells were cultured in the presence of platelet-rich plasma and studied for their proliferative capacity (growth curve, doubling time, and colony forming unit), differentiation properties, expression of mesenchymal markers, and Klotho protein. Morphologically, all cells were elongated and fibroblast-like. USCs isolated from samples collected by spontaneous micturition and bladder catheterization failed to proliferate, whilst USCs obtained by cystocentesis showed a doubling time of 2.04 days in healthy dogs and 1.7 days in dogs with CKD (p < 0.05). Cells were able to differentiate into osteogenic, chondrogenic, and adipogenic lines, showed positive expression to mesenchymal/stem markers, negative expression to hematopoietic markers, and major histocompatibility complex (MHCII) antigen. Klotho protein expression was confirmed. This study confirmed that USCs from healthy and CKD dogs can act as stem cells, with those from sick dogs having greater proliferative ability with the potential for use as autologous therapies. [ABSTRACT FROM AUTHOR]

Platelet-Rich Plasma (PRP) is a biological treatment widely used in regenerative medicine for its restorative capacity. Although PRP is typically applied at the time of obtention, long-term storage and preservation could enhance its versatility and clinical applications. The objective of this study was to evaluate the effect of long-term freezing on PRP. For that, PRP and Platelet Lysates (PL) were collected and preserved at −20 °C and −80 °C for 6 and 12 months. The parameters analyzed included platelet count and size, fibrinogen levels, platelet activation percentage, growth factor (GF) levels, and bioactivity on cultured dermal fibroblasts. No significant changes in platelet count were found; however, variations in platelet size were observed. Platelets stored at −20 °C and −80 °C showed structural changes and increased activation over time, including membrane roughness and possible aggregation. GF analysis revealed a reduction in platelet-derived growth factors (PDGF-AB and VEGF), while extraplatelet factors like IGF-1 remained stable. Fibroblast cultures showed comparable cell viability when exposed to fresh and cryopreserved PRP and PL samples. These findings suggest that cryopreserving PRP at −20 °C or −80 °C for up to 12 months is a feasible approach for retaining its therapeutic potential, supporting its use in biobanking, and expanding clinical accessibility. [ABSTRACT FROM AUTHOR]

BACKGROUND: Platelet-derived extracellular vesicles are the most abundant vesicles in the circulation, rich in bioactive molecules, genetic material, proteins and other information molecules, involved in cellular communication and material exchange, not only has good procoagulant activity, but also has the promotion of tissue repair and regeneration, and has a wide range of applications in regenerative medicine. OBJECTIVE: To elaborate the secretion mechanism of platelet-derived extracellular vesicles, their application in regenerative medicine, and limiting factors for clinical transformation, and to provide some theoretical support for the clinical translation of platelet-derived extracellular vesicles. METHODS: A computerized search of the PubMed database from January 2005 to August 2023 was applied to articles relating to platelet-derived extracellular vesicles with the search terms “platelet-derived, platelet-rich plasma, extracellular vesicles, isolated, microvesicles exosomes, applications”. A total of 62 articles that met the subject criteria were finally included. RESULTS AND CONCLUSION: (1) Activated platelet-derived extracellular vesicles produce two types of vesicles, platelet-derived microparticles, whose secretion may be associated with the asymmetry of the actin cytoskeleton, and platelet-derived exosomes, which may be associated with the regulation of H+ -ATPase. (2) Platelet-derived extracellular vesicles are potential effectors of platelet concentrates and platelets themselves, and may intervene in tissue regeneration by promoting angiogenesis, influencing cellular behavior, promoting coagulation and hemostasis, and exerting inflammatory effects. (3) Platelet-derived extracellular vesicles have been reported preclinically in the field of regenerative medicine such as tissue injury, muscle regeneration, cartilage regeneration, and osteoarthritis, and clinical trial data are available as potential therapeutic approaches for wound healing. However, factors such as isolation methods, sample sources, and the types of activators limit the clinical translation of platelet-derived extracellular vesicles into the field of regenerative medicine. (4) In the future, platelet-derived extracellular vesicles may become a cell-free alternative to platelet-rich plasma in regenerative medicine, but the clinical translation of platelet-derived extracellular vesicles needs to actively search for specific markers to differentiate platelet-derived microparticles from plateletderived exosomes. The mechanism of activator-stimulated platelet-derived extracellular vesicle production, as well as the optimal method of platelet-derived extracellular vesicle collection, the optimal method of storage, the shelf life of the platelet-derived extracellular vesicles, the recommended dosage of plateletderived extracellular vesicles for clinical application, and the optimal clinical indications need to be further investigated. [ABSTRACT FROM AUTHOR]

Tendon injuries present significant medical, social, and economic challenges globally. Despite advancements in tendon injury repair techniques, outcomes remain suboptimal due to inferior tissue quality and functionality. Tissue engineering offers a promising avenue for tendon regeneration, with biocompatible scaffolds playing a crucial role. Ostrich eggshell membrane (ESM), characterized by a strong preferential orientation of calcite crystals, forms a semipermeable polymer network with excellent mechanical properties compared to membranes from other bird species, emerging as a potential natural scaffold candidate. Coupled with platelet-rich plasma (PRP), known for its regenerative properties, ESM holds promise for improving tendon repair. This study aims to evaluate the biocompatibility and efficacy of an ESM-PRP scaffold in treating Achilles tendon ruptures, employing in vitro and in vivo assessments to gauge its potential in tendon regeneration in living organisms. Ostrich ESM was prepared from pathogen-free ostrich eggs, sterilized with UV radiation and prepared in desired dimensions before implantation (1.5 × 1 cm). High-resolution scanning electron microscopy (HRSEM) was utilized to visualize the sample morphology and fiber bonding. In vitro biocompatibility was assessed using the MTT assay and DAPI staining, while in vivo biocompatibility was evaluated in a rat model. For the in vivo Achilles tendinopathy assay, rats were divided into groups and subjected to AT rupture followed by treatment with ESM, PRP, or a combination. SEM was employed to evaluate tendon morphology, and real-time PCR was conducted to analyze gene expression levels. The in vivo assay indicated that the ESM scaffold was safe for an extended period of 8 weeks, showing no signs of inflammation based on histopathological analysis. In the Achilles tendon rupture model, combining ESM with PRP enhanced tendon healing after 14 weeks post-surgery. This finding was supported by histopathological, morphological, and mechanical evaluations of tendon tissues compared to normal tendons, untreated tendinopathy, and injured tendons treated with the ESM scaffold. Gene expression analysis revealed significantly increased expression of Col1a1, Col3a1, bFGF, Scleraxis (Scx), and tenomodulin in the ESM-PRP groups. The findings of our study demonstrate that the combination of Ostrich ESM with PRP significantly enhances AT repair and is a biocompatible scaffold for the application in living organisms. [ABSTRACT FROM AUTHOR]