Drag Reduction by Polymers in Saline Nutrient Solutions

2020 ◽  
Vol 142 (8) ◽  
Author(s):  
Renata T. Silva ◽  
Aloysio A. S. Campos ◽  
Edson J. Soares ◽  
Leonardo dos Santos ◽  
Renato N. Siqueira
Keyword(s):  
Drag Reduction ◽  
Blood Circulation ◽  
Industrial Applications ◽  
Blood Proteins ◽  
Experimental Conditions ◽  
Beneficial Effects ◽  
Artificial Plasma ◽  
Nutrient Solutions

Abstract Drag reduction (DR) by polymers has several industrial applications, and it has also shown to produce beneficial effects on blood circulation and may represent a way to treat cardiovascular disorders. Concerning medical applications, there are basically two types of studies using drag reducing polymers (DRP), i.e., in vitro and in vivo. Although blood may be used in the in vitro studies, there are several limitations, such as incompatibility of Rh and possibility of denaturing blood proteins. Thus, biomedical researchers commonly use an artificial plasma-like saline nutrient solution (SNS), which contains ions, nutrients, a buffer to maintain pH levels and a supply of oxygen to the tissue. The behavior of the DRP in water is well reported in the literature, but the SNS components can interact with the polymers, changing their capacity to reduce drag. This study investigates the behavior of three different polymers, i.e., polyacrylamide (PAM), polyethylene oxide (PEO), and xanthan gum (XG), when applied as DRP to a commonly used SNS. For the conditions evaluated, the SNS composition does not change significantly PAM and PEO behavior, showing that they can be satisfactorily diluted in this solvent without loss of efficiency as drag reducers. However, it modifies XG conformation, drastically reducing its efficiency. The experiments with tail arterial beds suggest that PAM is efficient to reduce the perfusion pressure, but PEO and XG do not seem to be good reducers under the experimental conditions that have been analyzed, possibly due to the interaction of the drag reducers with the flow, with the solvent components and with the tissues that were kept alive during the experiments. Although PEO did not present a good performance as DRP for the conditions evaluated in the perfusion tests, its performance can be improved in other organs where the turbulence levels, or instabilities, are higher, as suggested by the rheometer tests.

Factors affecting in vitro and in vivo antioxidant effects. Experimental conditions and nature of oxidants determine antioxidant efficacy

2021 ◽  
pp. 1-9
Author(s):  
Etsuo Niki
Keyword(s):  
Biological Molecules ◽  
Experimental Conditions ◽  
Factors Affecting ◽  
Beneficial Effects ◽  
Multiple Oxidants ◽  
Antioxidant Effects

Reactive oxygen and nitrogen species have been implicated in the onset and progression of various diseases and the role of antioxidants in the maintenance of health and prevention of diseases has received much attention. The action and effect of antioxidants have been studied extensively under different reaction conditions in multiple media. The antioxidant effects are determined by many factors. This review aims to discuss several important issues that should be considered for determination of experimental conditions and interpretation of experimental results in order to understand the beneficial effects and limit of antioxidants against detrimental oxidation of biological molecules. Emphasis was laid on cell culture experiments and effects of diversity of multiple oxidants on antioxidant efficacy.

scholarly journals Dietary compounds as potential modulators of microRNA expression in psoriasis

2019 ◽  
Vol 10 ◽  
pp. 204062231986480 ◽  
Author(s):  
Hristina Kocic ◽  
Giovanni Damiani ◽  
Bojana Stamenkovic ◽  
Michael Tirant ◽  
Andrija Jovic ◽  
...  
Keyword(s):  
Vitamin D ◽  
Omega 3 ◽  
Experimental Conditions ◽  
Keratinocyte Proliferation ◽  
Methyl Donors ◽  
Beneficial Effects ◽  
Small Noncoding Rnas ◽  
The Impact

Nutrigenomic DNA reprogramming in different chronic diseases and cancer has been assessed through the stimulation of gene expression and mRNA synthesis versus DNA silencing by CpG DNA modification (methylation); histone modification (acetylation, methylation) and expression of small noncoding RNAs, known as microRNAs (miRNAs). With regard to the specific nutrigenomic effects in psoriasis, the influence of specific diets on inflammatory cell signaling transcriptional factors such as nuclear factor (NF)-κB and Wnt signaling pathways, on disease-related specific cytokine expression, pro/antioxidant balance, keratinocyte proliferation/apoptosis and on proliferation/differentiation ratio have been documented; however, the influence of dietary compounds on the balance between ‘good and bad’ miRNA expression has not been considered. This review aims to summarize knowledge about aberrant microRNAs expression in psoriasis and to emphasize the potential impact of some dietary compounds on endogenous miRNA synthesis in experimental conditions in vivo and in vitro. Among the aberrantly expressed miRNAs in psoriasis, one of the most prominently upregulated seems to be miR-21. The beneficial effects of phenolic compounds (curcumin and resveratrol), vitamin D, methyl donors, and omega-3 fatty acids (eicosapentaenoic acid and docosahexaenoic acid) are discussed. Highly expressed miR-155 has been downregulated by flavonoids (through a quercetin-rich diet) and by vitamin D. Quercetin has been effective in modulating miR-146a. On the other hand, downregulated miR-125b expression was restored by vitamin D, Coenzyme Q10 and by microelement selenium. In conclusion, the miRNA profile, together with other ‘omics’, may constitute a multifaceted approach to explore the impact of diet on psoriasis prevention and treatment.

scholarly journals Antioxidant and Anti-Inflammaging Ability of Prune (Prunus Spinosa L.) Extract Result in Improved Wound Healing Efficacy

Antioxidants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 374
Author(s):  
Sofia Coppari ◽  
Mariastella Colomba ◽  
Daniele Fraternale ◽  
Vanessa Brinkmann ◽  
Margherita Romeo ◽  
...  
Keyword(s):  
Wound Healing ◽  
Umbilical Vein ◽  
Ethanol Extract ◽  
Typical Feature ◽  
Biologically Active ◽  
Experimental Conditions ◽  
Beneficial Effects ◽  
Prunus Spinosa

Prunus spinosa L. fruit (PSF) ethanol extract, showing a peculiar content of biologically active molecules (polyphenols), was investigated for its wound healing capacity, a typical feature that declines during aging and is negatively affected by the persistence of inflammation and oxidative stress. To this aim, first, PSF anti-inflammatory properties were tested on young and senescent LPS-treated human umbilical vein endothelial cells (HUVECs). As a result, PSF treatment increased miR-146a and decreased IRAK-1 and IL-6 expression levels. In addition, the PSF antioxidant effect was validated in vitro with DPPH assay and confirmed by in vivo treatments in C. elegans. Our findings showed beneficial effects on worms’ lifespan and healthspan with positive outcomes on longevity markers (i.e., miR-124 upregulation and miR-39 downregulation) as well. The PSF effect on wound healing was tested using the same cells and experimental conditions employed to investigate PSF antioxidant and anti-inflammaging ability. PSF treatment resulted in a significant improvement of wound healing closure (ca. 70%), through cell migration, both in young and older cells, associated to a downregulation of inflammation markers. In conclusion, PSF extract antioxidant and anti-inflammaging abilities result in improved wound healing capacity, thus suggesting that PSF might be helpful to improve the quality of life for its beneficial health effects.

scholarly journals Characterization and Functional Test of Canine Probiotics

2021 ◽  
Vol 12 ◽  
Author(s):  
Hyun-Jun Jang ◽  
Seungwoo Son ◽  
Jung-Ae Kim ◽  
Min Young Jung ◽  
Yeon-jae Choi ◽  
...  
Keyword(s):  
Animal Health ◽  
Clinical Results ◽  
Industrial Applications ◽  
Bacterial Strains ◽  
Host Animal ◽  
Microbial Composition ◽  
Beneficial Effects ◽  
Acid And Bile Tolerance

Probiotics can modulate the composition of gut microbiota and benefit the host animal health in multiple ways. Lactic acid bacteria (LAB), mainly Lactobacillus and Bifidobacterium species, are well-known microbes with probiotic potential. In the present study, 88 microbial strains were isolated from canine feces and annotated. Among these, the four strains CACC517, 537, 558, and 566 were tested for probiotic characteristics, and their beneficial effects on hosts were evaluated both in vitro and in vivo; these strains exhibited antibiosis, antibiotic activity, acid and bile tolerance, and relative cell adhesion to the HT-29 monolayer cell line. Byproducts of these strains increased the viability and decreased oxidative stress in mouse and dog cell lines (RAW264.7 and DH82, respectively). Subsequently, when the probiotics were applied to the clinical trial, changes in microbial composition and relative abundance of bacterial strains were clearly observed in the experimental animals. Experimental groups before and after the application were obviously separated from PCA analysis of clinical results. Conclusively, these results could provide comprehensive understanding of the effects of probiotic strains (CACC517, 537, 558, and 566) and their industrial applications.

Anti-atherosclerotic effects of fruit bioactive compounds: A review of current scientific evidence

2012 ◽  
Vol 92 (3) ◽  
pp. 407-419 ◽  
Author(s):  
Surangi H. Thilakarathna ◽  
H. P. Vasantha Rupasinghe
Keyword(s):  
Bioactive Compounds ◽  
Antioxidant Activities ◽  
Scientific Evidence ◽  
Experimental Models ◽  
Lipid Lowering ◽  
Experimental Conditions ◽  
Beneficial Effects ◽  
Positive Effects

Thilakarathna, S. H. and Rupasinghe, H. P. V. 2012. Anti-atherosclerotic effects of fruit bioactive compounds: A review of current scientific evidence. Can. J. Plant Sci. 92: 407–419. Atherosclerosis is a condition which leads to a cascade of processes involved in thickening of arterial walls as a result of fatty deposition, which can increase the risk of cardiovascular diseases. Among numerous remedies, the consumption of fruits is believed to have beneficial effects on atherosclerosis development. Various bioactive compounds are present in fruits and they have been found to be responsible for exerting these beneficial effects. Fruit flavonoids and certain terpenoids are among the most efficacious fruit bioactive compounds that have shown positive effects on different in vitro as well as in vivo research models of atherosclerosis. The mechanisms of actions of these compounds vary from exerting antioxidant activities to anti-atherogenic and lipid lowering activities, based on different experimental models. This review article briefly explains how some of the fruit bioactive compounds have affected atherosclerosis under experimental conditions.

scholarly journals Investigating Therapeutic Potential ofTrigonella foenum-graecumL. as Our Defense Mechanism against Several Human Diseases

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Shivangi Goyal ◽  
Nidhi Gupta ◽  
Sreemoyee Chatterjee
Keyword(s):  
Defense Mechanism ◽  
Therapeutic Potential ◽  
Chemical Constituents ◽  
Industrial Applications ◽  
Steroidal Saponin ◽  
Active Constituent ◽  
Beneficial Effects ◽  
Major Chemical

Current lifestyle, stress, and pollution have dramatically enhanced the progression of several diseases in human. Globally, scientists are looking for therapeutic agents that can either cure or delay the onset of diseases. Medicinal plants from time immemorial have been used frequently in therapeutics. Of many such plants, fenugreek is one of the oldest herbs which have been identified as an important medicinal plant by the researchers around the world. It is potentially beneficial in a number of diseases such as diabetes, hypercholesterolemia, and inflammation and probably in several kinds of cancers. It has industrial applications such as synthesis of steroidal hormones. Its medicinal properties and their role in clinical domain can be attributed to its chemical constituents. The 3 major chemical constituents which have been identified as responsible for principle health effects are galactomannan, 4-OH isoleucine, and steroidal saponin. Numerous experiments have been carried outin vivoandin vitrofor beneficial effects of both the crude chemical and of its active constituent. Due to its role in health care, the functional food industry has referred to it as a potential nutraceutical. This paper is about various medicinal benefits of fenugreek and its potential application as therapeutic agent against several diseases.

Superoxide, Xanthine Oxidase and Platelet Reactions: Further Studies on Mechanisms by which Oxidants Influence Platelets

1981 ◽  
Vol 45 (03) ◽  
pp. 290-293 ◽  
Author(s):  
Peter H Levine ◽  
Danielle G Sladdin ◽  
Norman I Krinsky
Keyword(s):  
Superoxide Dismutase ◽  
Cytochrome C ◽  
Xanthine Oxidase ◽  
Direct Effect ◽  
Platelet Function ◽  
Experimental Conditions ◽  
Release Reaction

SummaryIn the course of studying the effects on platelets of the oxidant species superoxide (O- 2), Of was generated by the interaction of xanthine oxidase plus xanthine. Surprisingly, gel-filtered platelets, when exposed to xanthine oxidase in the absence of xanthine substrate, were found to generate superoxide (O- 2), as determined by the reduction of added cytochrome c and by the inhibition of this reduction in the presence of superoxide dismutase.In addition to generating Of, the xanthine oxidase-treated platelets display both aggregation and evidence of the release reaction. This xanthine oxidase induced aggreagtion is not inhibited by the addition of either superoxide dismutase or cytochrome c, suggesting that it is due to either a further metabolite of O- 2, or that O- 2 itself exerts no important direct effect on platelet function under these experimental conditions. The ability of Of to modulate platelet reactions in vivo or in vitro remains in doubt, and xanthine oxidase is an unsuitable source of O- 2 in platelet studies because of its own effects on platelets.

Desmopressin (DDAVP) Enhances Platelet Adhesion to the Extracellular Matrix of Cultured Human Endothelial Cells through Increased Expression of Tissue Factor

1997 ◽  
Vol 77 (05) ◽  
pp. 0975-0980 ◽  
Author(s):  
Angel Gálvez ◽  
Goretti Gómez-Ortiz ◽  
Maribel Díaz-Ricart ◽  
Ginés Escolar ◽  
Rogelio González-Sarmiento ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Endothelial Cells ◽  
Tissue Factor ◽  
Platelet Adhesion ◽  
Umbilical Vein ◽  
Procoagulant Activity ◽  
Experimental Conditions ◽  
Chromogenic Assay

SummaryThe effect of desmopressin (DDAVP) on thrombogenicity, expression of tissue factor and procoagulant activity (PCA) of extracellular matrix (ECM) generated by human umbilical vein endothelial cells cultures (HUVEC), was studied under different experimental conditions. HUVEC were incubated with DDAVP (1, 5 and 30 ng/ml) and then detached from their ECM. The reactivity towards platelets of this ECM was tested in a perfusion system. Coverslips covered with DD A VP-treated ECMs were inserted in a parallel-plate chamber and exposed to normal blood anticoagulated with low molecular weight heparin (Fragmin®, 20 U/ml). Perfusions were run for 5 min at a shear rate of 800 s1. Deposition of platelets on ECMs was significantly increased with respect to control ECMs when DDAVP was used at 5 and 30 ng/ml (p <0.05 and p <0.01 respectively). The increase in platelet deposition was prevented by incubation of ECMs with an antibody against human tissue factor prior to perfusion. Immunofluorescence studies positively detected tissue factor antigen on DDAVP derived ECMs. A chromogenic assay performed under standardized conditions revealed a statistically significant increase in the procoagulant activity of the ECMs produced by ECs incubated with 30 ng/ml DDAVP (p <0.01 vs. control samples). Northern blot analysis revealed increased levels of tissue factor mRNA in extracts from ECs exposed to DDAVP. Our data indicate that DDAVP in vitro enhances platelet adhesion to the ECMs through increased expression of tissue factor. A similar increase in the expression of tissue factor might contribute to the in vivo hemostatic effect of DDAVP.

Applicability of Instability Index for In vitro Protein Stability Prediction

2019 ◽  
Vol 26 (5) ◽  
pp. 339-347 ◽  
Author(s):  
Dilani G. Gamage ◽  
Ajith Gunaratne ◽  
Gopal R. Periyannan ◽  
Timothy G. Russell
Keyword(s):  
Protein Stability ◽  
Caulobacter Crescentus ◽  
Effect Of Temperature ◽  
Instability Index ◽  
Dipeptide Composition ◽  
Experimental Conditions ◽  
The Stability ◽  
Vitro Protein

Background: The dipeptide composition-based Instability Index (II) is one of the protein primary structure-dependent methods available for in vivo protein stability predictions. As per this method, proteins with II value below 40 are stable proteins. Intracellular protein stability principles guided the original development of the II method. However, the use of the II method for in vitro protein stability predictions raises questions about the validity of applying the II method under experimental conditions that are different from the in vivo setting. Objective: The aim of this study is to experimentally test the validity of the use of II as an in vitro protein stability predictor. Methods: A representative protein CCM (CCM - Caulobacter crescentus metalloprotein) that rapidly degrades under in vitro conditions was used to probe the dipeptide sequence-dependent degradation properties of CCM by generating CCM mutants to represent stable and unstable II values. A comparative degradation analysis was carried out under in vitro conditions using wildtype CCM, CCM mutants and two other candidate proteins: metallo-β-lactamase L1 and α -S1- casein representing stable, borderline stable/unstable, and unstable proteins as per the II predictions. The effect of temperature and a protein stabilizing agent on CCM degradation was also tested. Results: Data support the dipeptide composition-dependent protein stability/instability in wt-CCM and mutants as predicted by the II method under in vitro conditions. However, the II failed to accurately represent the stability of other tested proteins. Data indicate the influence of protein environmental factors on the autoproteolysis of proteins. Conclusion: Broader application of the II method for the prediction of protein stability under in vitro conditions is questionable as the stability of the protein may be dependent not only on the intrinsic nature of the protein but also on the conditions of the protein milieu.

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