scholarly journals A Comparative Study of the Effects of Anticoagulants on Pure Platelet-Rich Plasma Quality and Potency

Biomedicines ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 42 ◽  
Author(s):  
Hachidai Aizawa ◽  
Hideo Kawabata ◽  
Atsushi Sato ◽  
Hideo Masuki ◽  
Taisuke Watanabe ◽  
...  
Keyword(s):  
Ethylenediaminetetraacetic Acid ◽  
Platelet Rich Plasma ◽  
In Vivo Studies ◽  
Negative Effects ◽  
Acid Citrate Dextrose ◽  
Citrate Dextrose ◽  
High Level ◽  
Activation Status

It is generally accepted that citrate or the A-form of acid-citrate-dextrose (ACD-A) are suitable for preparing platelet-rich plasma (PRP) for regenerative therapy. However, this is based on evidence from blood transfusions and not from regenerative medicine. Thus, we examined the effects of anticoagulants, such as ACD-A, ethylenediaminetetraacetic acid (EDTA), and heparin, on the regenerative quality of PRP to address this gap. The blood samples were collected in the presence of anticoagulants and were processed to prepare pure-PRP. Platelet size, activation status, and intra-platelet free Ca2+ concentration were determined while using a hematology analyzer and flow cytometer. Platelet-derived growth factor-BB (PDGF-BB) was quantified while using an ELISA. In pure-PRP samples, EDTA caused platelet swelling and activation, but yielded the highest number of platelets. Heparin aggregated platelets and disturbed the overall counting of blood cells. However, no significant differences in PDGF-BB levels were observed among the anticoagulants tested. Moreover, when considering the easy preparation of platelet suspensions, without the need for high-level pipetting skills, these findings suggest the comparable potency of EDTA-derived pure-PRP in tissue regeneration and support the use of EDTA in the preparation of pure-PRP. Further in vivo studies are required in animal models to exclude the possible negative effects of including EDTA in pure-PRP preparations.

Quantification of Platelet Adsesion in vivo

1979 ◽  
Author(s):  
H. Kortenhaus ◽  
G.V.R. Bom
Keyword(s):  
Fluorescence Microscopy ◽  
Small Proportion ◽  
Platelet Rich Plasma ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Golden Hamsters ◽  
Cardiac Blood ◽  
Acid Citrate Dextrose ◽  
Citrate Dextrose

Golden hamsters (80-100g) were anaesthetised with pentobarbital and cardiac blood was collected into acid-citrate dextrose. Platelet-rich plasma brought to pH 6.2 was incubated at 37° with fluorescein-isothiocyanate (FITC: 100 μg/ml) for 10 min (Kortenhaus , Webelmann and Schroer: to be published). The platelets were injected i.v. into another hamster and observed in the cheek pouch circulation by fluorescence microscopy at x 500.In venules a small proportion of platelets were arrested, most for less than one sec., about 20% for up to 2 min and about 3% for longer. There was no correlation with rolling granulocyte frequencies (A therton & Born, 1972, Journal of Fhysiology, 222, 447).

Conditions Affecting the Responses of Human Platelets to Epinephrine

1988 ◽  
Vol 60 (02) ◽  
pp. 209-216 ◽  
Author(s):  
Chantal Lalau Keraly ◽  
Raelene L Kinlough-Rathbone ◽  
Marian A Packham ◽  
Hidenori Suzuki ◽  
J Fraser Mustard
Keyword(s):  
Platelet Rich Plasma ◽  
Shape Change ◽  
Human Platelets ◽  
Dense Granule ◽  
Primary Phase ◽  
Lag Phase ◽  
Acid Citrate Dextrose ◽  
Two Phases ◽  
Citrate Dextrose ◽  
Thromboxane Formation

SummaryConditions affecting the responses of human platelets to epinephrine were examined. In platelet-rich plasma prepared from blood anticoagulated with hirudin or PPACK (D-pheny- lalanyl-L-prolyl-L-arginine chloromethyl ketone), epinephrine did not cause shape change or aggregation. In a Tyrode-albumin- apyrase solution containing a concentration of Ca2+ in the physiological range, and fibrinogen, epinephrine in concentrations as high as 40 μM did not induce platelet shape change, caused either no primary aggregation or very slight primary aggregation, and did not induce thromboxane formation, release of dense granule contents, or secondary aggregation. In contrast, in citrated platelet-rich plasma, epinephrine induced two phases of aggregation. This is not attributable to the generation of traces of thrombin since the same effects were evident when blood was taken into a combined citrate-hirudin anticoagulant or a combined citrate-PPACK anticoagulant. In a modified Tyrode-albu- min-apyrase solution containing approximately 20 μM Ca2+, 1 mM Mg2+, and fibrinogen, epinephrine induced extensive aggregation after a lag phase, but no primary phase was evident; thromboxane formation and release of dense granule contents accompanied the aggregation response. These responses were also observed when PPACK was included with the acid-citrate- dextrose anticoagulant, and in the washing and resuspending fluids. In the presence of aspirin or the thromboxane receptor blocker BM 13.177 a few small aggregates were detected by particle counting and by scanning electron microscopy; with the latter inhibitor, the platelets in the aggregates retained their disc shape; secondary aggregation and the responses associated with it did not occur. Thus thromboxane A2 formation is not necessary for the formation of these small aggregates, but is required for extensive aggregation and release. As with other weak agonists, the close platelet-to-platelet contact in the low Ca2+ medium appears to be necessary for full secondary aggregation. Omission of fibrinogen from the low Ca2+ medium prevented both primary and secondary aggregation in response to epinephrine. An antibody (10E5) to the glycoprotein Ilb/IIIa complex was completely inhibitory in the presence of fibrinogen. Thus the response of human platelets to epinephrine is influenced by the concentration of Ca2+ and the presence of fibrinogen in the medium in which they are suspended.

Transplantation of Adipose-derived Cells for Periodontal Regeneration: A Systematic Review

2019 ◽  
Vol 14 (6) ◽  
pp. 504-518 ◽  
Author(s):  
Dilcele Silva Moreira Dziedzic ◽  
Bassam Felipe Mogharbel ◽  
Priscila Elias Ferreira ◽  
Ana Carolina Irioda ◽  
Katherine Athayde Teixeira de Carvalho
Keyword(s):  
Systematic Review ◽  
Animal Models ◽  
Platelet Rich Plasma ◽  
Periodontal Regeneration ◽  
In Vitro Studies ◽  
In Vivo Studies ◽  
Cell Sources ◽  
Study Designs

This systematic review evaluated the transplantation of cells derived from adipose tissue for applications in dentistry. SCOPUS, PUBMED and LILACS databases were searched for in vitro studies and pre-clinical animal model studies using the keywords “ADIPOSE”, “CELLS”, and “PERIODONTAL”, with the Boolean operator “AND”. A total of 160 titles and abstracts were identified, and 29 publications met the inclusion criteria, 14 in vitro and 15 in vivo studies. In vitro studies demonstrated that adipose- derived cells stimulate neovascularization, have osteogenic and odontogenic potential; besides adhesion, proliferation and differentiation on probable cell carriers. Preclinical studies described improvement of bone and periodontal healing with the association of adipose-derived cells and the carrier materials tested: Platelet Rich Plasma, Fibrin, Collagen and Synthetic polymer. There is evidence from the current in vitro and in vivo data indicating that adipose-derived cells may contribute to bone and periodontal regeneration. The small quantity of studies and the large variation on study designs, from animal models, cell sources and defect morphology, did not favor a meta-analysis. Additional studies need to be conducted to investigate the regeneration variability and the mechanisms of cell participation in the processes. An overview of animal models, cell sources, and scaffolds, as well as new perspectives are provided for future bone and periodontal regeneration study designs.

scholarly journals GPR21 Inhibition Increases Glucose-Uptake in HepG2 Cells

2021 ◽  
Vol 22 (19) ◽  
pp. 10784
Author(s):  
Gemma K. Kinsella ◽  
Stefania Cannito ◽  
Valentina Bordano ◽  
John C. Stephens ◽  
Arianna C. Rosa ◽  
...  
Keyword(s):  
Glucose Uptake ◽  
Hepg2 Cells ◽  
Insulin Signalling ◽  
Hepatic Insulin Resistance ◽  
In Vivo Studies ◽  
Negative Effects ◽  
Cellular Models ◽  
Insulin Signalling Pathway ◽  
Novel Strategy

GPR21 is a constitutively active, orphan, G-protein-coupled receptor, with in vivo studies suggesting its involvement in the modulation of insulin sensitivity. However, its precise contribution is not fully understood. As the liver is both a major target of insulin signalling and critically involved in glucose metabolism, the aim of this study was to examine the role of GPR21 in the regulation of glucose uptake and production in human hepatocytes. In particular, HepG2 cells, which express GPR21, were adopted as cellular models. Compared with untreated cells, a significant increase in glucose uptake was measured in cells treated with siRNA to downregulate GPR21 expression or with the GPR21-inverse agonist, GRA2. Consistently, a significantly higher membrane translocation of GLUT-2 was measured under these conditions. These effects were accompanied by an increased ratio of phAKT(Ser473)/tot-AKT and phGSK-3β(Ser9)/tot-GSK-3β, thus indicating a marked activation of the insulin signalling pathway. Moreover, a significant reduction in ERK activation was observed with GPR21 inhibition. Collectively, these results indicate that GPR21 mediates the negative effects on glucose uptake by the liver cells. In addition, they suggest that the pharmacological inhibition of GPR21 could be a novel strategy to improve glucose homeostasis and counteract hepatic insulin resistance.

scholarly journals How to Achieve High-Quality Oocytes? The Key Role of Myo-Inositol and Melatonin

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Salvatore Giovanni Vitale ◽  
Paola Rossetti ◽  
Francesco Corrado ◽  
Agnese Maria Chiara Rapisarda ◽  
Sandro La Vignera ◽  
...  
Keyword(s):  
Assisted Reproductive Technologies ◽  
Reproductive Technologies ◽  
Oocyte Quality ◽  
Fertilization Rate ◽  
In Vitro Models ◽  
The One ◽  
High Level

Assisted reproductive technologies (ART) have experienced growing interest from infertile patients seeking to become pregnant. The quality of oocytes plays a pivotal role in determining ART outcomes. Although many authors have studied how supplementation therapy may affect this important parameter for both in vivo and in vitro models, data are not yet robust enough to support firm conclusions. Regarding this last point, in this review our objective has been to evaluate the state of the art regarding supplementation with melatonin and myo-inositol in order to improve oocyte quality during ART. On the one hand, the antioxidant effect of melatonin is well known as being useful during ovulation and oocyte incubation, two occasions with a high level of oxidative stress. On the other hand, myo-inositol is important in cellular structure and in cellular signaling pathways. Our analysis suggests that the use of these two molecules may significantly improve the quality of oocytes and the quality of embryos: melatonin seems to raise the fertilization rate, and myo-inositol improves the pregnancy rate, although all published studies do not fully agree with these conclusions. However, previous studies have demonstrated that cotreatment improves these results compared with melatonin alone or myo-inositol alone. We recommend that further studies be performed in order to confirm these positive outcomes in routine ART treatment.

Comparative lyophilized platelet-rich plasma wafer and powder for wound-healing enhancement: formulation, in vitro and in vivo studies

2019 ◽  
Vol 45 (8) ◽  
pp. 1379-1387 ◽  
Author(s):  
Ghada E. Yassin ◽  
Marwa H. S. Dawoud ◽  
Reham Wasfi ◽  
Ahmed Maher ◽  
Ahmed M. Fayez
Keyword(s):  
Wound Healing ◽  
Platelet Rich Plasma ◽  
In Vivo Studies

scholarly journals Targeting Wnt/β-Catenin Pathway for Developing Therapies for Hair Loss

2020 ◽  
Vol 21 (14) ◽  
pp. 4915 ◽  
Author(s):  
Bu Young Choi
Keyword(s):  
Hair Loss ◽  
Hair Growth ◽  
In Vivo Studies ◽  
Intracellular Targets ◽  
Remarkable Progress ◽  
Made In

Persistent hair loss is a major cause of psychological distress and compromised quality of life in millions of people worldwide. Remarkable progress has been made in understanding the molecular basis of hair loss and identifying valid intracellular targets for designing effective therapies for hair loss treatment. Whereas a variety of growth factors and signaling pathways have been implicated in hair cycling process, the activation of Wnt/β-catenin signaling plays a central role in hair follicle regeneration. Several plant-derived chemicals have been reported to promote hair growth by activating Wnt/β-catenin signaling in various in vitro and in vivo studies. This mini-review sheds light on the role of Wnt/β-catenin in promoting hair growth and the current progress in designing hair loss therapies by targeting this signaling pathway.

Antibacterial properties and in vivo studies of tannic acid-stabilized silver–halloysite nanomaterials

Clay Minerals ◽  
2020 ◽  
Vol 55 (2) ◽  
pp. 112-119
Author(s):  
Anna Stavitskaya ◽  
Christina Shakhbazova ◽  
Yulia Cherednichenko ◽  
Läysän Nigamatzyanova ◽  
Gölnur Fakhrullina ◽  
...  
Keyword(s):  
Tannic Acid ◽  
Antibacterial Properties ◽  
Halloysite Nanotubes ◽  
In Vivo Studies ◽  
Negative Effects ◽  
Antibacterial Performance ◽  
Synthesis Strategy ◽  
Clay Nanotubes

AbstractTannic acid-stabilized silver nanoparticles were synthesized in situ on halloysite clay nanotubes. The synthesis strategy included simple steps of tannic acid adsorption on clay nanotubes and further particle formation from silver salt solution. Pristine halloysite nanotubes as well as amino-modified clays were used for silver stabilization in water or ethanol. The materials were tested for antibacterial performance using three different methods. All of the materials produced showed antimicrobial activity. The pristine halloysite-based material with ~5 nm particles produced using ethanol as the solvent and tannic acid as the reducing agent showed the greatest antibacterial activity against Serratia marcescens. The materials were tested in vivo on Caenorhabditis elegans nematodes to ensure their safety, and they showed no negative effects on nematode growth and life expectancy.

scholarly journals Impact of the Different Preparation Methods to Obtain Autologous Non-Activated Platelet-Rich Plasma (A-PRP) and Activated Platelet-Rich Plasma (AA-PRP) in Plastic Surgery: Wound Healing and Hair Regrowth Evaluation

2020 ◽  
Vol 21 (2) ◽  
pp. 431 ◽  
Author(s):  
Pietro Gentile ◽  
Claudio Calabrese ◽  
Barbara De Angelis ◽  
Laura Dionisi ◽  
Jacopo Pizzicannella ◽  
...  
Keyword(s):  
Platelet Rich Plasma ◽  
Quality Criteria ◽  
Preparation Technique ◽  
Quality And Safety ◽  
Preparation Methods ◽  
Closed Technique ◽  
Sterile Processing

Autologous therapies using platelet-rich plasma (PRP) need meticulous preparation—currently, no standardised preparation technique exists. Processing Quantitative Standards (PQSs) define manufacturing quantitative variables (such as time, volume and pressure). Processing Qualitative Standards (PQLSs) define the quality of the materials and methods of manufacturing. The aim of this review is to use existing PQSs and PQLs to report the in vivo/in vitro results obtained by using different Kits, that utilise different procedures (classified as Closed-Technique and Opened-Technique) to isolate autologous human activated (AA-PRP) or non-activated PRP (A-PRP). PQSs included the volumes of blood collected as well as the reagents used, the time/gravity of centrifugation, and the duration, temperature and tilt level/speed of centrifugation. PQLSs included the use of Calcium Chloride CaCl2, Kit weight, transparency of Kit components, the maintenance of a closed sterile processing environment and the use of a small centrifuge. Eight CE marked devices for PRP extraction were evaluated: Angel®, Biomed®, Cascade® and Selphyl®, Mag-18®, i-Stem®, MyCells® and Regenlab®. Using a Kit with the PQSs and PQLSs described in this study enables the isolation of A-PRP, thereby meeting consensus quality criteria. As our understanding of Critical Quality Attributes (CQAs) of A-PRP continues to evolve, especially with respect to purity and potency, adjustments to these benchmark PQSs and PQLs will hopefully help isolate A-PRP of desired CQAs with greater reproducibility, quality, and safety. Confirmatory studies will no doubt need to be completed.

The Effect of Methylprednisolone Sodium Succinate on Erythrocyte and Haemoglobin Function

1980 ◽  
Vol 59 (3) ◽  
pp. 163-168 ◽  
Author(s):  
M. Brada ◽  
L. A. Robinson ◽  
A. J. Bellingham
Keyword(s):  
Whole Blood ◽  
Sodium Succinate ◽  
Oxygen Affinity ◽  
Whole Cells ◽  
Methylprednisolone Sodium Succinate ◽  
Acid Citrate Dextrose ◽  
Citrate Dextrose ◽  
Therapeutic Doses

1. As it has been suggested that the beneficial effect of methylprednisolone in shock is due to its effect on erythrocyte oxygen affinity, we studied its effect on incubated erythrocytes and on haemoglobin solution. 2. Incubation of fresh whole blood anticoagulated with acid/citrate/dextrose with methylprednisolone (7 mmol/l) produced a significant decrease in oxygen affinity, which was not seen with lower concentrations of methylprednisolone. When either acid/citrate/dextrose blood stored for 10 days or fresh heparinized blood was used, no significant increase in the partial pressure of oxygen at 50% haemoglobin saturation (P50) was demonstrated even with methylprednisolone at 7 mmol/l. At the highest concentration achieved in plasma with standard therapeutic doses (56 μmol/l) there was no increase in P50 under all the conditions studied. 3. Methylprednisolone reduced the oxygen affinity of haemoglobin in solution. The reduction in oxygen affinity was less than that produced by 2,3-diphosphoglycerate and more than that of either sodium succinate or sodium chloride. 4. From the results of this study we conclude that the effect observed in whole cells is probably due to a direct effect of methylprednisolone on haemoglobin. To produce a significant decrease of oxygen affinity of whole blood in vitro requires a plasma concentration of methylprednisolone above that obtained in plasma in vivo, with the currently used therapeutic doses.

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