A Comparative Study of The Effects of Anticoagulants on Pure Platelet-Rich Plasma Quality and Potency

Electromagnetic Iontophoresis: A Novel Nonsurgical Method for the Treatment of Dense Vitreous and Retinal Hemorrhages

Introduction

Vitreous, retinal, and suprochoroidal hemorrhages might develop secondary to trauma, retinal tear or detachment, neovascularization due to ischemic retina. If the clearance of retinal and vitreous hemorrhages can be accelerated, more effective treatments can be planned for the underlying pathology.

Case Presentations

We present 6 different cases with dense vitreous, preretinal, and subretinal hemorrhages due to Valsalva retinopathy, polypoid choroidal vasculopathy, diabetic retinopathy, neovascular age-related macular degeneration, retinitis pigmentosa with vasculitis, and myopic choroidal neovascularization. To accelerate the clearance of these dense intraocular hemorrhages, a novel nonsurgical method of electromagnetic iontophoresis (MagnoVision™) was used together with some appropriate medications in an outpatient setting without any complications or side effects. In all cases, liquefaction of the intraocular hemorrhage began by 5 days and mostly resolved by 10 days. This nonsurgical rapid clearance allowed us to diagnose and evaluate the underlying retinal and choroidal pathologies earlier and to treat them appropriately as early as possible.

Conclusion

Combined use of electromagnetic iontophoresis, subtenon platelet-rich plasma and bevacizumab injection, and oral bromelain can be considered as an effective and safe new treatment method for vitreous and retinal hemorrhages without any need for surgical intervention.

Update on Platelet-Rich Plasma and Platelet-Rich Fibrin for Dermatologic Surgery: Addressing Knowns and Unknowns

BACKGROUND

Autologous and allogeneic platelet-rich plasma (PRP) in addition to its derivatives, such as platelet-rich fibrin (PRF), are broadly accepted therapeutic approaches in orthopedics, otolaryngology, sports medicine, plastic surgery, and oral and maxillofacial surgery. However, the absence of expert consensus, standardized protocols, and varying outcomes pose challenges to their broader acceptance in cosmetic dermatology and dermatologic surgery.

OBJECTIVE

To offer a contemporary literature overview of PRP and PRF, focusing on fundamental aspects of the technology, diversity of commercially accessible systems, and shed light on present-day controversies within the field.

METHODS

A systemic review of PRP and PRF literature was conducted, utilizing search engine databases: Cochrane Database of Systematic Reviews, Embase, Ovid MEDLINE, and PubMed. Emphasis was placed on scrutinizing higher level-of-evidence articles, specifically randomized control trials, systematic reviews, and meta-analyses (Level 1A-2A), with particular emphasis on recent data that have not been well reviewed in other publications from January 2022 to May 2024.

RESULTS

An increasing body of literature affirms advantages of PRP products in dermatology, spanning wound care, facial rejuvenation, scar revision, and hair growth.

CONCLUSION

A foundational understanding of variation in preparation protocol, outcomes, and timing of administration is needed to better comprehend market dynamics, patient demand, and strategies for integrating PRP into dermatologic practice.

The Role of Autologous Platelet Concentrates as a Local Antibiotic Delivery System: A Systematic Scoping Review

OBJECTIVES

Ongoing research has begun to develop innovative approaches to deliver local antibiotics while minimizing systemic side effects, antimicrobial resistance, and limited tissue penetration. Autologous platelet concentrates (APCs) offer promise in delivering antibiotics directly to infection sites. Despite the interest, a comprehensive evaluation of their effectiveness is lacking. Therefore, this systematic scoping review aims to collect and appraise studies regarding the efficacy of APCs in delivering antibiotics.

METHODS

A systematic electronic search of PubMed, Scopus, and Web of Science, using a combination of keywords, was conducted up to February 2024. Articles addressing the use of APCs as a local antibiotic delivery system were included.

RESULTS

A total of 13 articles, including 10 in vitro studies, 1 in vitro and clinical study, 1 ex vivo study, and 1 clinical study, were selected. Antibiotic loading capacity and release was confirmed in all studies using doxycycline, gentamicin, linezolid, vancomycin, metronidazole, and penicillin. In addition, the antibacterial effect was obtained mainly against E. coli., P. aeruginosa, S. mitis, H. influenzae, S. pneumoniae, and S. aureus.

CONCLUSIONS

The incorporation of antibiotics into APCs has been proven to facilitate the effective release of antimicrobial agents at optimal concentrations, potentially reducing the incidence of post-operative infections, substituting, or augmenting systemic antibiotic treatment while retaining APCs' inherent healing properties.

In Vitro and In Silico Characterization of the Aggregation of Thrombi on Textured Ventricular Cannula

The unacceptably high stroke rate associated with HeartMate 3 ventricular assist device (VAD) without signs of adherent pump thrombosis is hypothesized to be the result of the emboli produced by the inflow cannula, that are ingested and ejected from the pump. This in vitro and numerical study aimed to emulate the surface features and supraphysiological shear of a ventricular cannula to provide insight into their effect on thrombogenesis. Human whole blood was perfused at calibrated flow rates in a microfluidic channel to achieve shear rates 1000-7500 s-1, comparable to that experienced on the cannula. The channel contained periodic teeth representative of the rough sintered surface of the HeartMate 3 cannula. The deposition of fluorescently labeled platelets was visualized in real time and analyzed with a custom entity tracking algorithm. Numerical simulations of a multi-constituent thrombosis model were performed to simulate laminar blood flow in the channel. The sustained growth of adherent platelets was observed in all shear conditions ( p <  0.05). However, the greatest deposition was observed at the lower shear rates. The location of deposition with respect to the microfluidic teeth was also found to vary with shear rate. This was confirmed by CFD simulation. The entity tracking algorithm revealed the spatial variation of instances of embolic events. This result suggests that the sintered surface of the ventricular cannula may engender unstable thrombi with a greater likelihood of embolization at supraphysiological shear rates.

Revitalizing female fertility: platelet-rich plasma - hype or hope?

Platelet-rich plasma (PRP) has gained popularity as an experimental tool in regenerative medicine, with potential applications in reproductive medicine. This review will assess the existing literature on the role of PRP in female fertility enhancement, focusing on ovarian rejuvenation and increased endometrial thickness. PRP is being explored as a treatment for recurrent implantation failure, primary ovarian insufficiency and poor ovarian response. While the influence of PRP on endometrial thickness and implantation success is postulated, its effectiveness remains the subject of debate due to protocol variability and unclear patient selection criteria. This narrative review includes 36 articles published before December 2022, and highlights the lack of comprehensive molecular studies examining the impact of PRP on reproductive capacity. This review underscores the importance of standardizing PRP preparation protocols in reproductive medicine. However, challenges persist, and there is a need for well-planned randomized controlled trials and a deeper understanding of the patient population that would gain the greatest benefit from PRP treatment. Clarifying these aspects is crucial to improve outcomes for low-prognosis patients undergoing assisted reproductive technology.

Plasma Gel Matrix as a Promising Carrier of Epigallocatechin Gallate for Regenerative Medicine

Plasma gel (PG) is a protein matrix prepared from platelet-poor plasma and can be utilized as a drug carrier for controlled release. We previously demonstrated its applicability as a carrier of polyphosphate. Epigallocatechin-3-gallate (EGCG) is the main flavonoid found in green tea and functions as a strong antioxidant. To explore the applicability of PG as an EGCG carrier, we examined the release of EGCG from the PG matrix using an in vitro system. Pooled platelet-poor plasma (PPP) was prepared from four healthy adult male donors, mixed with EGCG, and heated at 75 °C for 10 or 20 min to prepare the PG matrix. The PG-EGCG matrix was incubated in PBS at 37 °C, and the EGCG released into PBS was determined using spectrophotometry. The antioxidant capacity was determined based on the principle of the iodine decolorization reaction. EGCG precipitated and incorporated into the PG matrix during thermal preparation. Trypsin, used to simulate the in vivo degradation of PG, released EGCG from the PG matrix over time. The released EGCG maintained its antioxidant capacity during incubation. These results indicate that thermally prepared PG matrices can be utilized as a promising EGCG carrier in the fields of tissue engineering and regenerative medicine.

Advances and prospects of platelet-rich plasma therapy in veterinary ophthalmology

In the recent decades, there has been a significant uptick on the use of platelet-rich plasma (PRP) as a better alternative for ophthalmologic therapies in pathologies, primarily of the ocular surface. PRP is a class of liquid platelet concentrate containing a supra-physiological concentration of platelets in a relatively small amount of plasma. Its potential to heal various tissues has piqued interest in its therapeutic application as a biomaterial in regenerative medicine. It is currently a popular therapeutic agent in plastic surgery, cardiothoracic surgery, reconstructive surgery, and even oral and maxillofacial surgery. Based on the data from in vitro and in vivo studies, it can be concluded that PRP possesses adequate therapeutic potential in ocular pathologies, especially those involving cornea. In addition, the high concentrations of growth factors (TGF-β, VEGF, EGF) present in the PRP accelerate the healing of the corneal epithelium. PRP has great therapeutic prospects in veterinary ophthalmology as a regenerative therapeutic modality. However, several variables are yet to be defined and standardized that can directly affect the efficacy of PRP application in different ophthalmic conditions. There is a shortage of research on the use of PRP in ocular surface defects compared to the number of studies and reports on the use of autologous and allogeneic serum eye drops. Therefore, a data-driven approach is required to generate consensus/guidelines for the preparation, characterization, and therapeutic use of PRP in veterinary ophthalmology. This review aims to inform readers of the latest research on PRP, including its preparation methods, physiological and biochemical properties, clinical applications in veterinary ophthalmology, and their safety and efficacy.

Variations in the full blood count parameters among apparently healthy humans in the Ho municipality using ethylenediamine tetraacetic acid (EDTA), sodium citrate and lithium heparin anticoagulants: A laboratory-based cross-sectional analytical study

Background

Several studies have shown that various anticoagulants used for collection of blood samples produce varying effects on haematological analyses. Tripotassium ethylenediamine tetra-acetic acid (K₃EDTA), sodium citrate and lithium heparin remain the most used anticoagulants employed in hematological analysis. There is paucity of data on the effect of these anticoagulants on haematological parameters in humans in Ghana. We assessed the suitability of K₃EDTA, sodium citrate and lithium heparin for routine Full Blood Count (FBC) investigation.

Method

A laboratory-based analytical cross-sectional study was conducted using blood samples from 55 conveniently sampled apparently healthy tertiary students from January 2021 to October 2021. Blood samples were taken from each participant into 3 anticoagulant tubes: K₃EDTA, sodium citrate and lithium heparin and FBC parameters estimated using the Mindray automated haematology analyzer. One-way ANOVA Kruskal-Wallis test, Mann-Whitney U, Intra-class correlation coefficient (ICC) analysis, Bland-Altman's plot and Lin's concordance correlation coefficient were used where appropriate to ascertain the level of variation, consistency, and agreements among and between results. Normality testing using Shapiro-Wilk test statistic revealed non-Gaussian distribution of data, hence, were presented as median, minimum, and maximum. Data generated were analyzed using STATA v15 and MedCalc v20 where appropriate for statistical analysis. P-values <0.05 were considered statistically significant.

Results

The study comprised 34 males and 21 females. The median age for males (23 years: min = 20, max = 34) was statistically comparable (p = 0.2652) to that of females (22 years: min = 18, max = 34). We observed excellent consistency in the estimation of MCV (ICC = 0.94), MCH (ICC = 0.98), MCHC (ICC = 0.91), GRAN# (ICC = 0.92) and LYMPH% (ICC = 0.91) across the three anticoagulants. Heparin and K₃EDTA largely agreed on most of the FBC parameters, 50.0% (7/14) including HGB, MCV, MCH, PLT, LYMPH#, GRAN# and GRAN%. Meanwhile using K₃EDTA as a standard, heparin produced almost perfect agreement only in the assessment of RBC (CCC = 0.992) while a substantial agreement was observed in the assessment of HGB (0.971), HCT (0.958) and MCH (0.987). Citrate agreed substantially with K₃EDTA in the assessment of LYMPH% (CCC = 0.964) and moderately in the assessment of MCV (CCC = 0.948) and MCH (0.913). Overall, compared to K₃EDTA, heparin was highly precise and accurate in the estimation of HGB, RBC, HCT and MCH while citrate determined MCV and MCH more accurately and precisely.

Conclusion

Citrated blood consistently produced lower FBC values compared to heparin and K₃EDTA and hence suggests not reliable in the assessment of FBC among humans. Heparin agreed largely with K₃EDTA in the estimation of FBC parameters and may be used as a better alternative anticoagulant in the absence of K₃EDTA however with great caution.

Blood Biomarkers Discriminate Cerebral Amyloid Status and Cognitive Diagnosis when Collected with ACD-A Anticoagulant

BACKGROUND

The development of biomarkers that are easy to collect, process, and store is a major goal of research on current Alzheimer's Disease (AD) and underlies the growing interest in plasma biomarkers. Biomarkers with these qualities will improve diagnosis and allow for better monitoring of therapeutic interventions. However, blood collection strategies have historically differed between studies. We examined the ability of various ultrasensitive plasma biomarkers to predict cerebral amyloid status in cognitively unimpaired individuals when collected using acid citrate dextrose (ACD). We then examined the ability of these biomarkers to predict cognitive impairment independent of amyloid status.

METHODS

Using a cross-sectional study design, we measured amyloid beta 42/40 ratio, pTau-181, neurofilament-light, and glial fibrillary acidic protein using the Quanterix Simoa® HD-X platform. To evaluate the discriminative accuracy of these biomarkers in determining cerebral amyloid status, we used both banked plasma and 18F-AV45 PET cerebral amyloid neuroimaging data from 140 cognitively unimpaired participants. We further examined their ability to discriminate cognitive status by leveraging data from 42 cognitively impaired older adults. This study is the first, as per our knowledge, to examine these specific tests using plasma collected using acid citrate dextrose (ACD), as well as the relationship with amyloid PET status.

RESULTS

Plasma AB42/40 had the highest AUC (0.833, 95% C.I. 0.767-0.899) at a cut-point of 0.0706 for discriminating between the two cerebral amyloid groups (sensitivity 76%, specificity 78.5%). Plasma NFL at a cut-point of 20.58pg/mL had the highest AUC (0.908, 95% CI 0.851- 0.966) for discriminating cognitive impairment (sensitivity 84.8%, specificity 89.9%). The addition of age and apolipoprotein e4 status did not improve the discriminative accuracy of these biomarkers.

CONCLUSION

Our results suggest that the Aβ42/40 ratio is useful in discriminating clinician-rated elevated cerebral amyloid status and that NFL is useful for discriminating cognitive impairment status. These findings reinforce the growing body of evidence regarding the general utility of these biomarkers and extend their utility to plasma collected in a non-traditional anticoagulant.

Platelet polyphosphate and energy metabolism in professional male athletes (soccer players): A cross-sectional pilot study

Human platelet polyphosphate (polyP) is a multifunctional molecule; however, its functions are not yet fully understood. A recent study demonstrated that similar to skeletal muscle, polyP is involved in energy metabolism in platelets, which suggests that well-trained athletes may exhibit elevated platelet polyP levels for energy storage. To test this hypothesis, we quantified platelet polyP along with NADH, a component involved in ATP production in non-trained and well-trained male Japanese participants of the same generation. Washed platelets were prepared from the venous blood of young, healthy, non-athletes, and professional soccer players (pro-athletes). NADH and polyP levels were spectrophotometrically determined using tetrazolium reduction and fluorometrically determined using 4',6-diamidino-2-phenylindole at the excitation/emission wavelengths of 425/525 nm. Body weight and impedances were measured simultaneously. Statistical analyses were performed using the Mann-Whitney U test and Spearman correlation coefficient. Although basal metabolic rate levels were significantly higher, platelet polyP levels were significantly lower in pro-athletes than in that in non-athletes. No significant differences were detected in other body compositions or platelet indices between the two groups. The pro-athlete group showed a moderate, nearly significant correlation (R = 0.439; p = 0.0512) between platelet polyP and NADH levels. Taken together with the weak correlation data between polyP and body mass index, it is suggested that platelet polyP levels may be influenced by platelet and body energy metabolic activity. Further biochemical studies are needed to elucidate this mechanism.

Platelet-rich plasma in hair loss-Mechanism, preparation, and classification

Platelet-rich plasma is the autologous plasma containing platelet concentration more than the baseline separated after centrifugation. It has become a very popular option for the treatment of hair loss in the past few decades. Used alone or in combination with other treatment options it has found a place as a hair restoration procedure throughout the world. However, evidence supporting its credibility is quite ambiguous with contradictory reports available in the literature. In this article, we try to analyze the available data regarding its mechanism of action, preparation protocols, and classification, with regard to hair loss.

PRP in wound healing applications

Platelets play a crucial role in hemostasis, tissue regeneration and host defense. Based on these settings, platelet-rich plasma (PRP) and its derivatives are therapeutically used to promote wound healing in several scenarios. This review summarizes the biological mechanisms underlying the most traditional as well as innovative applications of PRP in wound healing. These mechanisms involve the combined action of platelet-derived growth factors and cytokines, together with the role of plasma-derived fibrillar, antioxidant and homeostatic factors. In addition, regenerative treatments with PRP consist of personalized and non-standardized methods. Thus, the quality of PRP varies depending on endogenous factors (e.g., age; gender; concomitant medication; disease-associated systemic factors; nutrition) and exogenous factors (anticoagulants and cellular composition). This review also analyses whether these factors affect the biological mechanisms of PRP in wound healing applications.

Platelet adhesion on commercially pure titanium plates in vitro III: effects of calcium phosphate-blasting on titanium plate biocompatibility

BACKGROUND

Platelet-rich plasma (PRP) is often used to improve surface biocompatibility. We previously found that platelets rapidly adhere to plain commercially pure titanium (cp-Ti) plates in the absence, but not in the presence, of plasma proteins. To further expand on these findings, in the present study, we switched titanium plates from a plain surface to a rough surface that is blasted with calcium phosphate (CaP) powder and then examined platelet adhesion and activation.

METHODS

Elemental distribution in CaP-blasted cp-Ti plates was analyzed using energy-dispersive X-ray spectroscopy. PRP samples prepared from anticoagulated blood samples of six healthy, non-smoking adult male donors were loaded on CaP-blasted cp-Ti plates for 1 h and fixed for examination of platelet morphology and visualization of PDGF-B and platelet surface markers (CD62P, CD63) using scanning electron microscopy and fluorescence microscopy. Plain SUS316L stainless steel plates used in injection needles were also examined for comparison.

RESULTS

Significant amounts of calcium and phosphate were detected on the CaP-blasted cp-Ti surface. Platelets rapidly adhered to this surface, leading to higher activation. Platelets also adhered to the plain stainless surface; however, the levels of adhesion and activation were much lower than those observed on the CaP-blasted cp-Ti plate.

CONCLUSIONS

The CaP-blasted cp-Ti surface efficiently entraps and activates platelets. Biomolecules released from the activated platelets could be retained by the fibrin matrix on the surface to facilitate regeneration of the surrounding tissues. Thus, PRP immersion could not only eliminate surface air bubbles but also improve the biocompatibility of the implant surface.

The Platelet Concentrates Therapy: From the Biased Past to the Anticipated Future

The ultimate goal of research on platelet concentrates (PCs) is to develop a more predictable PC therapy. Because platelet-rich plasma (PRP), a representative PC, was identified as a possible therapeutic agent for bone augmentation in the field of oral surgery, PRP and its derivative, platelet-rich fibrin (PRF), have been increasingly applied in a regenerative medicine. However, a rise in the rate of recurrence (e.g., in tendon and ligament injuries) and adverse (or nonsignificant) clinical outcomes associated with PC therapy have raised fundamental questions regarding the validity of the therapy. Thus, rigorous evidence obtained from large, high-quality randomized controlled trials must be presented to the concerned regulatory authorities of individual countries or regions. For the approval of the regulatory authorities, clinicians and research investigators should understand the real nature of PCs and PC therapy (i.e., adjuvant therapy), standardize protocols of preparation (e.g., choice of centrifuges and tubes) and clinical application (e.g., evaluation of recipient conditions), design bias-minimized randomized clinical trials, and recognize superfluous brand competitions that delay sound progress. In this review, we retrospect the recent past of PC research, reconfirm our ultimate goals, and discuss what will need to be done in future.

Concentrated Growth Factor Matrices Prepared Using Silica-Coated Plastic Tubes Are Distinguishable From Those Prepared Using Glass Tubes in Platelet Distribution: Application of a Novel Near-Infrared Imaging-Based, Quantitative Technique

Platelet-rich fibrin (PRF) matrices were originally prepared using plain glass tubes without the aid of coagulation factors because coagulation factor XII is activated by glass surfaces. Recently, the use of silica-coated plastic tubes as a substitute of glass tubes has been recommended for PRF preparation. This recommendation is owing not only to the shortage of glass tubes for medical use in the market, but also the higher coagulation activity of silica-coated plastic tubes and equal quality of PRF. However, these matrices are not the same. To evaluate the differences, we compared glass- and silica-coated plastic tubes in terms of platelet distribution and quantity in concentrated growth factors (CGF). CGF matrices were immediately prepared from freshly collected blood samples, fixed after red thrombus removal, and divided into two equal pieces sagittally. One piece was used for CD41 detection and the other was applied as an isotype control. Platelet distribution in CGF matrices was examined, without embedding or sectioning, by a novel method using invisible near-infrared imaging. The dehydrated membranous CGF matrix was more transparent. Thus, the fluorescence signal was clearly detectable with less scattering. Platelets were distributed mainly in the distal side of the glass-prepared CGF matrix, but homogeneously in the silica-prepared CGF matrix. Platelet count was positively correlated with fluorescence intensity. Although not yet fully developed, this imaging technique enabled us to recognize the differences in platelet distribution and quantity in CGF matrices by excluding bias caused by the technical limitations of scanning electron microscopy and conventional immunohistochemical methods.