Differences in human and minipig platelet number, volume and activation induced by borosilicate glass beads in a modified chandler loop-system

2021 ◽  
Vol 79 (1) ◽  
pp. 149-155 ◽  
Author(s):  
G. Greif ◽  
C. Mrowietz ◽  
M. Wendt ◽  
F. Jung ◽  
B. Hiebl ◽  
...  
Keyword(s):  
Medical Devices ◽  
Human Platelets ◽  
Loop System ◽  
Large Animal Model ◽  
Large Animal ◽  
Platelet Volume ◽  
Cardiovascular Research ◽  
Activation Markers ◽  
Platelet Number ◽  
Chandler Loop

The pig is the most widely used large animal model in Europe, with cardiovascular research being one of the main areas of application. Adequate refinement of interventional studies in this field, meeting the requirements of Russel and Burchs’ 3 R concept, can only be performed if blood-contacting medical devices are hemocompatible. Because most medical devices for cardiovascular interventional procedures are developed for humans they are tested mostly for compatibility with human blood. The aim of this study was therefore to determine whether there are differences in behavior of porcine and human platelets when they come into contact with glass, which was used as an exemplary thrombogenic material. For this purpose changes of platelet count, platelet volume and platelet expression of the activation markers CD61, CD62P and CD63 were measured using a modified chandler loop-system simulating the fluidic effects of the blood flow. Minipig and human platelets showed significant differences in number and volume, but not in activation after 4–8 min exposure to glass.

Differences in human and sheep platelet adherence, aggregation and activation induced by glass beads in a modified chandler loop-system

2021 ◽  
pp. 1-8
Author(s):  
G. Greif ◽  
C. Mrowietz ◽  
H. Meyer-Sievers ◽  
M. Ganter ◽  
F. Jung ◽  
...  
Keyword(s):  
Platelet Count ◽  
Mean Platelet Volume ◽  
Human Platelets ◽  
Glass Beads ◽  
Loop System ◽  
Platelet Volume ◽  
Activation Markers ◽  
Chandler Loop ◽  
Silicon Tube ◽  
The Mean

In human cardiovascular research, sheep in particular are used as a large animal model in addition to pigs. In these animals, medical products, developed and tested for human medical purposes, are almost exclusively used in interventional studies. Therefore, the extent to which platelets from human and ovine blood differ in terms of adherence, aggregation and activation after a 4- or 8-minutes exposure to glass was investigated. Testing was performed with platelet-rich plasma (PRP) and a modified Chandler loop system, with 4- and 8-minute blood-material exposure times corresponding to 20 and 40 test cycles, respectively, through the entire silicon tube loop of the test system. In sheep and human PRP, contact with the silicone tubing resulted in a decrease in platelet count after 4 minutes and 20 test cycles, respectively. Four more minutes (20 additional test cycles) caused a further decrease of the platelet count only in sheep PRP. When the silicon tube was partly filled with glass beads, these effects were more pronounced and stronger in sheep then in human PRP. The mean platelet volume, which was used as parameter for platelet aggregation, did not change over time in human PRP without glass exposure. With glass exposure in human and sheep PRP the mean platelet volume increased within 40 test cycles, but this increase was stronger in sheep than in human PRP. Regarding activation behavior, the activation markers CD62P and CD63 were detectable only in < 30% (sheep) and < 45% (human) of platelets, whereas after 8 min of glass exposure, the proportion of CD62P+ and CD63+ cells was more increased than before only in sheep. These results indicate that ovine platelets adhere more strongly to glass and show stronger aggregation behavior after glass contact than human platelets, but that ovine and human platelets differ only slightly in activability by glass.

Abstract 265: Identification of MicroRNA in an Ovine Model of Heart Failure

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Lee Lee Wong ◽  
Eng Leng Saw ◽  
Kar Sheng Lew ◽  
Miriam T Rademaker ◽  
Leigh J Ellmers ◽  
...  
Keyword(s):  
Heart Failure ◽  
Heart Tissue ◽  
Left Ventricular ◽  
Ovis Aries ◽  
Large Animal Model ◽  
Large Animal ◽  
High Confidence ◽  
Cardiovascular Research ◽  
Sheep Model ◽  
Stem Loop

Introduction: The sheep ( Ovis aries ) provides a large animal model in cardiovascular research including heart failure (HF). However, microRNA (miR) related work in the sheep model has been limited due to a paucity of information regarding oar-miR. The aim of this study was to identify novel oar-miRs in myocardium and examine their regulation in HF and HF recovery. Methods: Heart tissue was harvested from sheep undergoing 1. HF induced by rapid left ventricular (LV) pacing at 225bpm for 14 days, 2. HF recovery (HF-R) after discontinuation of pacing for an additional 14 days and 3. Sham. LV miRs were examined using next generation deep sequencing (NGS), miR array and stem-loop qPCR. Sequences were aligned with miRBase v20.0 and mapped to ovine genome and miRBase Mature BLAST search engine. Plasma was collected to assess natriuretic peptides (ANP and BNP). Results: Three miR libraries were generated from NGS and a total of 619 miRs were detected. Of these, 93 were oar-miRs; 49 novel miRs (high confidence) mapped to ovine genome and perfectly aligned to mature miRs in other organisms (miRBase v20.0); 69 putative novel miRs (high confidence) that mapped to ovine genome and aligned partially to mature miRs of other species in miRBase v20.0; 168 miRs (low confidence) that mapped to ovine genome but unaligned to any known mature miRs; and 240 miRs (low confidence) that were unmapped to the sheep genome but aligned to either miRBase mature hsa-/mmu-/rno-miRs. Plasma BNP and ANP increased 19-folds and 18- folds respectively in HF, and returned to baseline in HF-R. MiR levels in HF model were examined using miR array. About 1000 miRs were detected from array and at least 301 of them were overlapped with NGS data. Using miR array profiling followed by stem-loop qPCR validation, we found that myocardial enriched miR-133b-3p, miR-208b-3p, miR-21-5p and miR-125a-5p, -125b-5p, -126-3p, -210-3p, and 29a-3p were significantly upregulated in HF (p<0.05 vs. Sham). All trended downwards towards baseline levels during recovery (HF-R) but only miR-210 was significant (p<0.001 vs. HF). Conclusion: We identified 118 novel oar-miRs with high confidence and 408 potential oar-miRs, which is a solid foundation for miR function studies using sheep models. We also identified miR changes in HF and HF-R.

A Relationship between Platelet Volume and Platelet Number

1974 ◽  
Vol 31 (02) ◽  
pp. 363-365 ◽  
Author(s):  
J. R O’Brien ◽  
Sandra Jamieson
Keyword(s):  
Platelet Volume ◽  
Platelet Number

Physiological Effects of Nonimmune Platelet Associated Immunoglobulin G

1981 ◽  
Vol 45 (01) ◽  
pp. 027-033 ◽  
Author(s):  
K Sugiura ◽  
M Steiner ◽  
M Baldini
Keyword(s):  
Shape Change ◽  
Fluorescein Isothiocyanate ◽  
Recovery Phase ◽  
Human Platelets ◽  
Serotonin Release ◽  
Platelet Volume ◽  
Igg Antibody ◽  
Heterologous Antiserum ◽  
Igg Binding ◽  
Series Of Experiments

SummaryThe function of nonimmune IgG associated with platelets is unknown. In a series of experiments we have investigated this problem, relating amount of platelet-associated IgG (PAIgG) to platelet volume, serotonin release, adherence of platelets to monocytes and platelet senescence. Most of these studies were performed with human platelets. Platelets freed of preexisting PAIgG by incubation at 22° C were incubated with IgG in a series of concentrations ranging from 0.4 — 27.0 X10-6 M. The IgG preparations used were demonstrably free of aggregated forms of the protein. The amount of PAIgG bound to platelets was determined by the use of fluorescein isothiocyanate-conjugated anti-IgG antibody (F-anti-IgG antibody) which was quantified in a fluorospectrophotometer. Newly bound IgG was assayed similarly by the use of F-IgG. A dose-dependent increase in platelet volume was associated with the binding of nonimmune IgG by platelets. The process which leveled off at an IgG concentration of 1.2 —1.5 X10-5 M was almost fully reversible and was not due to platelet shape change or aggregation. Release of serotonin from IgG-treated platelets was relatively small but to the extent that it occurred was positively related to the IgG concentration to which platelets were exposed. Adherence to autologous monocytes studied quantitatively by the use of formaldehyde-fixed cells was also positively related to the amount of IgG on the platelets. Normal or IgG-defident serum had a potent inhibitory (noncompetitive) action on the binding of F-IgG and F-anti-human IgG antibody to human platelets. Cohorts of platelets prepared in rabbits during the recovery phase of immunological thrombocytopenia induced by injection of heterologous antiserum, showed an age-dependent increase of PAIgG and of IgG binding. These results suggest that PAIgG plays a role in the clearance of senescent platelets.

DEVELOPMENT OF A LARGE ANIMAL MODEL OF OPIATE ADDICTION TO EVALUATE CARDIOVASCULAR FUNCTION.

Analgesia ◽  
1995 ◽  
Vol 1 (4) ◽  
pp. 598-602 ◽  
Author(s):  
L.D. Napier ◽  
Z. Mateo ◽  
D.A. Yoshishige ◽  
B.A. Barron ◽  
J.L. Caffrey
Keyword(s):  
Animal Model ◽  
Cardiovascular Function ◽  
Large Animal Model ◽  
Opiate Addiction ◽  
Large Animal

scholarly journals A novel large animal model of smoke inhalation-induced acute respiratory distress syndrome

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Premila D. Leiphrakpam ◽  
Hannah R. Weber ◽  
Andrea McCain ◽  
Roser Romaguera Matas ◽  
Ernesto Martinez Duarte ◽  
...  
Keyword(s):  
Animal Model ◽  
Acute Respiratory Distress Syndrome ◽  
Respiratory Distress Syndrome ◽  
Distress Syndrome ◽  
Inhalation Injury ◽  
Smoke Inhalation ◽  
Large Animal Model ◽  
Large Animal ◽  
X Ray ◽  
Chest X Ray

Abstract Background Acute respiratory distress syndrome (ARDS) is multifactorial and can result from sepsis, trauma, or pneumonia, amongst other primary pathologies. It is one of the major causes of death in critically ill patients with a reported mortality rate up to 45%. The present study focuses on the development of a large animal model of smoke inhalation-induced ARDS in an effort to provide the scientific community with a reliable, reproducible large animal model of isolated toxic inhalation injury-induced ARDS. Methods Animals (n = 21) were exposed to smoke under general anesthesia for 1 to 2 h (median smoke exposure = 0.5 to 1 L of oak wood smoke) after the ultrasound-guided placement of carotid, pulmonary, and femoral artery catheters. Peripheral oxygen saturation (SpO2), vital signs, and ventilator parameters were monitored throughout the procedure. Chest x-ray, carotid, femoral and pulmonary artery blood samples were collected before, during, and after smoke exposure. Animals were euthanized and lung tissue collected for analysis 48 h after smoke inhalation. Results Animals developed ARDS 48 h after smoke inhalation as reflected by a decrease in SpO2 by approximately 31%, PaO2/FiO2 ratio by approximately 208 (50%), and development of bilateral, diffuse infiltrates on chest x-ray. Study animals also demonstrated a significant increase in IL-6 level, lung tissue injury score and wet/dry ratio, as well as changes in other arterial blood gas (ABG) parameters. Conclusions This study reports, for the first time, a novel large animal model of isolated smoke inhalation-induced ARDS without confounding variables such as cutaneous burn injury. Use of this unique model may be of benefit in studying the pathophysiology of inhalation injury or for development of novel therapeutics.

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