Search results for "whole blood"

2020

The analysis of tumours using biomarkers in blood is transforming cancer diagnosis and therapy. Cancers are characterised by evolving genetic alterations, making it difficult to develop reliable and broadly applicable DNA-based biomarkers for liquid biopsy. In contrast to the variability in gene mutations, the methylation pattern remains generally constant during carcinogenesis. Thus, methylation more than mutation analysis may be exploited to recognise tumour features in the blood of patients. In this work, we investigated the possibility of using global CpG (CpG means a CG motif in the context of methylation. The p represents the phosphate. This is used to distinguish CG sites meant for m…

Flow cytometric kinetic assay of calcium mobilization in whole blood platelets using Fluo-3 and CD41

1999

Background: Platelet activation plays a major role in the physiology and pathology of hemostasis. Flow cytometry is a promising approach for the structural and functional analysis of platelets. However, the choice of adequate biological parameters and most technical issues are still under discussion. A rise in cytosolic free Ca 21 is a key early event that follows platelet stimulation and precedes several activation responses, including shape change, aggregation, secretion, and expression of procoagulant activity. Our objective was to set up a fast and sensitive flow cytometric method to determine the kinetics of intracellular Ca 21 mobilization in platelets, which could be performed with t…

Oxygen-carrying v. non-oxygen-carrying colloidal blood substitutes in schock

1982

Loss of more than 10-15 per cent of the circulating blood causes a corresponding fall in filling pressure and a marked reduction in minute volume. In order to combat a fall in the minute volume, catecholamines are liberated, the stimulating components of these cause a rise in vessel tone. In spite of the blood volume being reduced by blood loss, filling pressure and minute volume are restored by compensating mechanisms as long as the volume lost is not enough to exceed the autoregulative capacity. Even with a blood loss of 10-15 per cent, full compensation is not achieved without replenishing the blood volume unless the fluid lost from the vascular bed is less than I0 per cent of the total.…

Mapping of activation frequencies during ventricular fibrillation in isolated perfused healthy human heart

2013

Whole blood endotoxin responsiveness in patients with chronic heart failure: the importance of serum lipoproteins.

2005

Background Endotoxin [lipopolysaccharide (LPS)] may be an important stimulus for cytokine release in patients with chronic heart failure (CHF). We sought to investigate the relationship between whole blood endotoxin responsiveness and serum lipoprotein concentrations. It is not known if low-dose LPS is sufficient to stimulate immune activation. Methods and results Whole blood from 32 CHF patients (mean age 66±2 years, NYHA class 2.7±0.2, five female) and 11 healthy control subjects (mean age 47±4 years, six female) was stimulated with LPS at nine different concentrations (0.001 to 10 ng/mL), and tumor necrosis factor (TNF-α) release was quantified. Reference standard endotoxin at concentrat…

Comprehensive platelet phenotyping supports the role of platelets in the pathogenesis of acute venous thromboembolism - results from clinical observa…

2020

Background: The pathogenesis of arterial and venous thrombosis is in large part interlaced. How much platelet phenotype relates to acute venous thromboembolism (VTE) independent of the underlying cardiovascular profile is presently poorly investigated.Methods: Platelet count and mean platelet volume (MPV), platelet aggregation in whole blood and platelet rich plasma (PRP), platelet-dependent thrombin generation (TG) and platelet surface activation markers were measured under standardized conditions. Machine learning was applied to identify the most relevant characteristics associated with VTE from a large array (N = 58) of clinical and plateletrelated variables.Findings: VTE cases (N = 159)…

Comparison of loop-mediated isothermal amplification (LAMP) and PCR for the diagnosis of infection with Trypanosoma brucei ssp. in equids in The Gamb…

2020

Introduction:\ud Infection of equids with Trypanosoma brucei (T. brucei) ssp. is of socioeconomic importance across sub-Saharan Africa as the disease often progresses to cause fatal meningoencephalitis. Loop-mediated isothermal amplification (LAMP) has been developed as a cost-effective molecular diagnostic test and is potentially applicable for use in field-based laboratories.\ud \ud Part I:\ud Threshold levels for T. brucei ssp. detection by LAMP were determined using whole equine blood specimens spiked with known concentrations of parasites. Results were compared to OIE antemortem gold standard of T. brucei-PCR (TBR-PCR).\ud \ud Results I:\ud Threshold for detection of T. brucei ssp. on …

A whole blood test to measure SARS-CoV-2-specific response in COVID-19 patients

2021

Objectives To examine whether specific T-cell-responses to SARS-CoV-2 peptides can be detected in COVID-19 using a whole-blood experimental setting, which may be further explored as potential diagnostic tool. Methods We evaluated IFN-γ levels after stimulating whole-blood with spike and remainder-antigens peptides megapools (MP) derived from SARS-CoV-2 sequences; IL-1β, IL-1RA, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-12p70, IL-13, IL-15, IL-17A, eotaxin, basic FGF, G-CSF, GM-CSF, IFN-γ, IP-10, MCP-1, MIP-1α, MIP-1β, PDGF, RANTES, TNF-α, VEGF were also evaluated. Results IFN-γ-response to spike and remainder-antigens MPs was significantly increased in 35 COVID-19-patients compare…

Roles of sedentary aging and lifelong physical activity in exchange of glutathione across exercising human skeletal muscle.

2014

Reactive oxygen species (ROS) are important signaling molecules with regulatory functions, and in young and adult organisms, the formation of ROS is increased during skeletal muscle contractions. However, ROS can be deleterious to cells when not sufficiently counterbalanced by the antioxidant system. Aging is associated with accumulation of oxidative damage to lipids, DNA, and proteins. Given the pro-oxidant effect of skeletal muscle contractions, this effect of age could be a result of excessive ROS formation. We evaluated the effect of acute exercise on changes in blood redox state across the leg of young (23±1 years) and older (66±2 years) sedentary humans by measuring the whole blood co…

Effect of soluble guanylyl cyclase activator and stimulator therapy on nitroglycerin-induced nitrate tolerance in rats

2015

Chronic nitroglycerin (GTN) anti-ischemic therapy induces side effects such as nitrate tolerance and endothelial dysfunction. Both phenomena could be based on a desensitization/oxidation of the soluble guanylyl cyclase (sGC). Therefore, the present study aims at investigating the effects of the therapy with the sGC activator BAY 60-2770 and the sGC stimulator BAY 41-8543 on side effects induced by chronic nitroglycerin treatment. Male Wistar rats were treated with nitroglycerin (100mg/kg/d for 3.5days, s.c. in ethanol) and BAY 60-2770 (0.5 or 2.5mg/kg/d) or BAY 41-8543 (1 and 5mg/kg/d) for 6days. Therapy with BAY 60-2770 but not with BAY 41-8543 improved nitroglycerin-triggered endothelial …