Minimization of Hemolysis in Centrifugal Blood Pumps: Influence of Different Geometries

1993 ◽  
Vol 16 (7) ◽  
pp. 521-529 ◽  
Author(s):  
H. Schima ◽  
M.R. MÜller ◽  
D. Papantonis ◽  
C. Schlusche ◽  
L. Huber ◽  
...  

Centrifugal blood pumps are of substantial importance for intraoperative extracorporeal circulation and for temporary cardiac assist. Their development and improvement raises many specific questions, especially on mechanical blood properties, flow distribution, and the resulting biocompatibility. In this comprehensive study the influence of various pump geometries on blood trauma was investigated. For this purpose analytical calculations, hydrodynamic performance, numerical simulation, in vitro hemolysis tests and in vivo experiments were used. The gap between rotor and housing was found to be crucial showing a distinct minimum of hemolysis at a gap of 1.5 mm (in vitro increase of plasma free hemoglobin per 100 ml plasma an hour: ΔfHb/hour = 2.4±0.83 mg%/h at 1.5 mm versus 12 ± 2.2 mg%/h at 2.5 mm; p < 0.05). Housing diameter and shape of the vanes were of less importance for blood traumatization (d = 60 mm: ΔfHb/hour = 6.36 ± 1.8 mg%/h; d = 70 mm: fHb = 7.1 ± 1.9 mg%/h; straight radial vanes: 5.2 ± 1.8 mg%/h; straight inclined vanes: 6.8 ± 1.2 mg%/h; flexed vanes: 6.1 ± 2.0 mg%/h). Three animal experiments confirmed the optimization of geometry, with a mean fHb of 2.5 to 3.2 mg% in steady state. Hydrodynamic efficiency revealed to be a necessary, but not a sufficient and sensitive criterion for hemolysis minimization (e.g. changes of η < 10% for changes of fHb > 500%). Numerical simulation gives an improved insight in flow distribution, but can not yet be applied for quantification of blood trauma. The study supports theories on mechanical hemolysis predicting a hemolysis at shear levels of less than 500N/m2 depending on exposure time. With the methods used it was possible to develop a pump with very low hemolysis potential. For further reduction of blood trauma and correlated thrombus formation basic studies on cell damage in recirculating blood and also advanced flow studies in rotary pumps would be desirable.

Author(s):  
Huiling Zhou ◽  
Lijun Liu ◽  
Xiaolong Ma ◽  
Jian Wang ◽  
Jinfu Yang ◽  
...  

AbstractVinblastine (VBL) has been considered as a first-line anti-tumor drug for many years. However, vinblastine-caused myocardial damage has been continually reported. The underlying molecular mechanism of the myocardial damage remains unknown. Here, we show that vinblastine induces myocardial damage and necroptosis is involved in the vinblastine-induced myocardial damage both in vitro and in vivo. The results of WST-8 and flow cytometry analysis show that vinblastine causes damage to H9c2 cells, and the results of animal experiments show that vinblastine causes myocardial cell damage. The necrosome components, receptor-interacting protein 1 (RIP1) receptor-interacting protein 3 (RIP3), are significantly increased in vinblastine-treated H9c2 cells, primary neonatal rat ventricular myocytes and rat heart tissues. And the downstream substrate of RIP3, mixed lineage kinase domain like protein (MLKL) was also increased. Pre-treatment with necroptosis inhibitors partially inhibits the necrosome components and MLKL levels and alleviates vinblastine-induced myocardial injury both in vitro and in vivo. This study indicates that necroptosis participated in vinblastine-evoked myocardial cell death partially, which would be a potential target for relieving the chemotherapy-related myocardial damage.


Author(s):  
I. А. Minigalieva ◽  
T. V. Bushueva ◽  
V. G. Panov ◽  
A. N. Varaksin ◽  
V. Ya. Shur ◽  
...  

Comparative and combined damaging actions of NiO and Mn3O4 anoparticles were estimated on cultures of different established human cell lines. It was found out that the addition of the fetal bovine serum (FBS) to the culture media ,used in the investigation, renders NiO-NPs and, to even a greater extent, Mn3O4-NPs exponentially soluble while without FBS their dissolution was extremely low. Along with it, sedimentation of those MeO-NPs caused by their aggregation noticeably slowed down in the presence of the same FBS. The dependence of cell damage on the MeO-NPs concentration was found out, at a higher cytotoxicity of Mn3O4-NP as compared to NiO-NP. Thus, comparative assessment of NPs non-specific toxicity previously obtained in animal experiments was reproduced in the «in vitro» tests. However, with respect to manganese-specific brain damage «in vivo» discovered previously in sub-chronic intoxication with the same MeO-NPs, the present «in vitro» experiment on neurons only showed a certain enhancing effect of Mn3O4-NP on the action of NiO-NP, but the role of NiO-NP in the combination prevailed.


Blood ◽  
1996 ◽  
Vol 88 (9) ◽  
pp. 3416-3423 ◽  
Author(s):  
P Sriramarao ◽  
LR Languino ◽  
DC Altieri

In addition to preserving hemostasis, fibrinogen assembly on leukocytes mediates inflammatory responses and may aberrantly contribute to vascular injury. In this study, we used real-time intravital video microscopy in exposed rabbit mesentery to investigate the potential role of fibrinogen on leukocyte adherence mechanisms, in vivo. At physiologic concentrations of 0.15 to 0.5 mg/mL, human fibrinogen dose-dependently enhanced by threefold to fivefold the adhesion of chemoattractant-stimulated monocytic HL-60 cells to rabbit mesenteric endothelium, by acting as a bridging molecule between the two types. Fibrinogen-dependent intercellular bridging occurred in venules, but not in arterioles or capillaries (1), was optimal at reduced flow shear forces (range: 0.77 to 2.79 dyne/cm2) (2), and produced a firm attachment of monocytic cells to endothelium, rather than transient rolling (3). Consistent with this model, rabbit fibrinogen failed to support human leukocyte adhesion, while human fibrinogen enhanced monocytic cell attachment to rabbit endothelial cells in vitro, in a reaction indistinguishable from that observed with human endothelium. Antagonists of the recently described association of fibrinogen with intercellular adhesion molecule-1 (ICAM-1), including monoclonal antibodies (MoAbs) LB-2 or 2D5, or the fibrinogen gamma 3 peptide gamma Asn117-Ala133, blocked fibrinogen-dependent leukocyte-endothelium interaction in vitro or in vivo, respectively, while a control nonbinding antibody or the fibrinogen L10 peptide gamma Leu402-Val411 were ineffective. These data suggest that simultaneous assembly of fibrinogen on leukocytes and endothelial ICAM-1 provides a pathway of intercellular adhesion which may act in concert with beta 2 integrins to stabilize firm leukocyte attachment to endothelium, in vivo. Given the recognized role of fibrinogen as a major risk factor for atherosclerosis, this mechanism may directly contribute to thrombus formation and endothelial cell damage in vascular diseases.


1980 ◽  
Vol 44 (02) ◽  
pp. 081-086 ◽  
Author(s):  
C V Prowse ◽  
A E Williams

SummaryThe thrombogenic effects of selected factor IX concentrates were evaluated in two rabbit models; the Wessler stasis model and a novel non-stasis model. Concentrates active in either the NAPTT or TGt50 in vitro tests of potential thrombogenicity, or both, caused thrombus formation in the Wessler technique and activation of the coagulation system in the non-stasis model. A concentrate with low activity in both in vitro tests did not have thrombogenic effects in vivo, at the chosen dose. Results in the non-stasis model suggested that the thrombogenic effects of factor IX concentrates may occur by at least two mechanisms. A concentrate prepared from platelet-rich plasma and a pyrogenic concentrate were also tested and found to have no thrombogenic effect in vivo.These studies justify the use of the NAPTT and TGt50 in vitro tests for the screening of factor IX concentrates prior to clinical use.


1986 ◽  
Vol 56 (03) ◽  
pp. 318-322 ◽  
Author(s):  
V Diness ◽  
P B Østergaard

SummaryThe neutralization of a low molecular weight heparin (LHN-1) and conventional heparin (CH) by protamine sulfate has been studied in vitro and in vivo. In vitro, the APTT activity of CH was completely neutralized in parallel with the anti-Xa activity. The APTT activity of LHN-1 was almost completely neutralized in a way similar to the APTT activity of CH, whereas the anti-Xa activity of LHN-1 was only partially neutralized.In vivo, CH 3 mg/kg and LHN-1 7.2 mg/kg was given intravenously in rats. The APTT and anti-Xa activities, after neutralization by protamine sulfate in vivo, were similar to the results in vitro. In CH treated rats no haemorrhagic effect in the rat tail bleeding test and no antithrombotic effect in the rat stasis model was found at a protamine sulfate to heparin ratio of about 1, which neutralized APTT and anti-Xa activities. In LHN-1 treated rats the haemorrhagic effect was neutralized when APTT was close to normal whereas higher doses of protamine sulfate were required for neutralization of the antithrombotic effect. This probably reflects the fact that in most experimental models higher doses of heparin are needed to induce bleeding than to prevent thrombus formation. Our results demonstrate that even if complete neutralization of APTT and anti-Xa activities were not seen in LHN-1 treated rats, the in vivo effects of LHN-1 could be neutralized as efficiently as those of conventional heparin. The large fall in blood pressure caused by high doses of protamine sulfate alone was prevented by the prior injection of LHN-1.


2020 ◽  
Author(s):  
K. Zerrouki ◽  
N. Djebli ◽  
L. Gadouche ◽  
I. Erdogan Orhan ◽  
F. SezerSenol Deniz ◽  
...  

Nowadays, because of the industrialization, a lot of contaminant were available ; the consequences of this availability are apparition of diseases including neurodegeneration. Neurodegenerative diseases of the human brain comprise a variety of disorders that affect an increasing percentage of the population. This study is based on the effect of the Boswellic resin, which is from a medicinal plant and known for its antioxidant effects on nerve cell damage. The objective of this work was to evaluate the in vitro and in vivo effects of the Boswellic resin on anticholinesterase activity and Alzheimer’s disease (AD) induced by D-galactose and aluminum tetrachloride in Swiss mice. Chemical composition of the resin essential oil was identified by the CG-MS analysis. The antioxidant activity was also assessed by the DMPD and metal chelation methods. In order to understand the mechanism of memory improvement, the acetylcholinesterase, AChE, and butyrylcholinesterase, BChE, inhibitory assays were performed. In vivo part of the study was achieved on Swiss mice divided into four groups: control, AD model, treated AD, and treated control group. The identification of chemical composition by CG-MS reach the 89.67% of the total extract compounds presented some very important molecules (p-Cymene, n-Octyl acetate, α-Pinene…). The present study proves that Boswellic resin improves memory and learning in treated Alzheimer’s group, modulates the oxidative stress and be involved in the protective effect against amyloid deposition and neurodegeneration, and stimulates the immune system in mice’s brain.


2020 ◽  
Vol 27 (10) ◽  
pp. 1634-1646 ◽  
Author(s):  
Huey-Shan Hung ◽  
Shan-hui Hsu

Treatment of cardiovascular disease has achieved great success using artificial implants, particularly synthetic-polymer made grafts. However, thrombus formation and restenosis are the current clinical problems need to be conquered. New biomaterials, modifying the surface of synthetic vascular grafts, have been created to improve long-term patency for the better hemocompatibility. The vascular biomaterials can be fabricated from synthetic or natural polymers for vascular tissue engineering. Stem cells can be seeded by different techniques into tissue-engineered vascular grafts in vitro and implanted in vivo to repair the vascular tissues. To overcome the thrombogenesis and promote the endothelialization effect, vascular biomaterials employing nanotopography are more bio-mimic to the native tissue made and have been engineered by various approaches such as prepared as a simple surface coating on the vascular biomaterials. It has now become an important and interesting field to find novel approaches to better endothelization of vascular biomaterials. In this article, we focus to review the techniques with better potential improving endothelization and summarize for vascular biomaterial application. This review article will enable the development of biomaterials with a high degree of originality, innovative research on novel techniques for surface fabrication for vascular biomaterials application.


2020 ◽  
Vol 15 (3) ◽  
pp. 193-206
Author(s):  
Brognara Lorenzo ◽  
Salmaso Luca ◽  
Mazzotti Antonio ◽  
Di M. Alberto ◽  
Faldini Cesare ◽  
...  

Background: Chronic wounds are commonly associated with polymicrobial biofilm infections. In the last years, the extensive use of antibiotics has generated several antibiotic-resistant variants. To overcome this issue, alternative natural treatments have been proposed, including the use of microorganisms like probiotics. The aim of this manuscript was to review current literature concerning the application of probiotics for the treatment of infected chronic wounds. Methods: Relevant articles were searched in the Medline database using PubMed and Scholar, using the keywords “probiotics” and “wound” and “injuries”, “probiotics” and “wound” and “ulcer”, “biofilm” and “probiotics” and “wound”, “biofilm” and “ulcer” and “probiotics”, “biofilm” and “ulcer” and “probiotics”, “probiotics” and “wound”. Results: The research initially included 253 articles. After removal of duplicate studies, and selection according to specific inclusion and exclusion criteria, 19 research articles were included and reviewed, accounting for 12 in vitro, 8 in vivo studies and 2 human studies (three articles dealing with animal experiments included also in vitro testing). Most of the published studies about the effects of probiotics for the treatment of infected chronic wounds reported a partial inhibition of microbial growth, biofilm formation and quorum sensing. Discussion: The application of probiotics represents an intriguing option in the treatment of infected chronic wounds with multidrug-resistant bacteria; however, current results are difficult to compare due to the heterogeneity in methodology, laboratory techniques, and applied clinical protocols. Lactobacillus plantarum currently represents the most studied strain, showing a positive application in burns compared to guideline treatments, and an additional mean in chronic wound infections. Conclusions: Although preliminary evidence supports the use of specific strains of probiotics in certain clinical settings such as infected chronic wounds, large, long-term clinical trials are still lacking, and further research is needed.


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 315
Author(s):  
Zhenxing Wang ◽  
Zongcai Tu ◽  
Xing Xie ◽  
Hao Cui ◽  
Kin Weng Kong ◽  
...  

This study aims to evaluate the bioactive components, in vitro bioactivities, and in vivo hypoglycemic effect of P. frutescens leaf, which is a traditional medicine-food homology plant. P. frutescens methanol crude extract and its fractions (petroleum ether, chloroform, ethyl acetate, n-butanol fractions, and aqueous phase residue) were prepared by ultrasound-enzyme assisted extraction and liquid–liquid extraction. Among the samples, the ethyl acetate fraction possessed the high total phenolic (440.48 μg GAE/mg DE) and flavonoid content (455.22 μg RE/mg DE), the best antioxidant activity (the DPPH radical, ABTS radical, and superoxide anion scavenging activity, and ferric reducing antioxidant power were 1.71, 1.14, 2.40, 1.29, and 2.4 times higher than that of control Vc, respectively), the most powerful α-glucosidase inhibitory ability with the IC50 value of 190.03 μg/mL which was 2.2-folds higher than control acarbose, the strongest proliferative inhibitory ability against MCF-7 and HepG2 cell with the IC50 values of 37.92 and 13.43 μg/mL, which were considerable with control cisplatin, as well as certain inhibition abilities on acetylcholinesterase and tyrosinase. HPLC analysis showed that the luteolin, rosmarinic acid, rutin, and catechin were the dominant components of the ethyl acetate fraction. Animal experiments further demonstrated that the ethyl acetate fraction could significantly decrease the serum glucose level, food, and water intake of streptozotocin-induced diabetic SD rats, increase the body weight, modulate their serum levels of TC, TG, HDL-C, and LDL-C, improve the histopathology and glycogen accumulation in liver and intestinal tissue. Taken together, P. frutescens leaf exhibits excellent hypoglycemic activity in vitro and in vivo, and could be exploited as a source of natural antidiabetic agent.


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