Search

Histamine has the ability to influence the activity of immune cells including neutrophils and plays a pivotal role in inflammatory processes, which are a complex network of cellular and humoral events. One of the main functions manifested by activated neutrophils is oxidative burst, which is linked to the production of reactive oxygen species; therefore, the effects of histamine receptor agonists and antagonists on the oxidative burst of neutrophils is reviewed. A role for the well-characterized histamine H1 and H2 receptors in this process is discussed and compared to that of the recently discovered H4 receptor. Linked Articles This article is part of a themed issue on Histamine Pharmacology Update. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2013.170.issue-1

Black chokeberry (Aronia melanocarpa) is a distinctive berry with a high content of polyphenol compounds and possesses one of the highest in vitro antioxidant activities among fruits. The bioavailability of aronia polyphenols seems to be low, but there is ample evidence for chokeberry health benefits including antidiabetic, cardioprotective, hepatoprotective, antimutagenic, and anticarcinogenic effects. This review presents the available information for the bioavailability and antioxidant activity of chokeberry polyphenols and explains the possible mechanisms of action in vivo in the prevention and treatment of oxidative stress-related diseases. The review shows the available data for chokeberry antioxidant activity in vitro, in isolated cells and cell lines, and in vivo, in both human subjects and animals. It is evident that in vivo antioxidant action of chokeberry extends far beyond radical scavenging and includes suppression of reactive oxygen and nitrogen species formation, inhibition of prooxidant enzymes, restoration of antioxidant enzymes, and probably cellular signaling to regulate the level of antioxidant compounds and enzymes. The original contribution of this work is that it compiles the available information up to date and outlines the gaps and future directions in the assessment of chokeberry antioxidant action in vivo.

Summary Introduction: The differentiation between extra- and intracellular production of reactive oxygen species (ROS) in whole blood was measured by luminol- and isoluminol-enhanced chemiluminescence (CL). Methods: Azide (total CL inhibition), azide + horseradish peroxidase (HRP, restoring extracellular CL), superoxide dismutase + catalase (depleting extracellular ROS) and HRP (enhancing extracellular CL) were used to modulate luminol- and isoluminol-enhanced CL (10−6–10−3 m luminophores) of 125× diluted whole blood which was activated by both calcium ionophore A23187 (Ca-I) and opsonized zymosan particles (OZP) separately. Results: Both activators stimulated intra- and extracellular production of ROS. Luminol-enhanced CL of Ca-I-activated samples detected the intracellular ROS, and with the addition of HRP detected the extracellular CL as well. CL enhanced with isoluminol in concentrations of 10−4 m or less was mostly extracellular. There was a mixture of intra- and extracellular CL in OZP-activated samples, probably because of the ingestion of luminophore molecules. Conclusion: Measurement of Ca-I-activated CL enhanced with 10−4 m luminol is recommended for the detection of intracellular ROS. The addition of HRP leads to the detection of overall ROS production while the OZP-activated system with its addition of HRP can only be used to detect overall ROS production. Ca-I-activated CL enhanced with 10−4 m isoluminol and with addition of HRP is recommended for the detection of extracellular CL.

– Objectives: The aim of this study was to develop an instrument measuring core concerns about dental treatment guided by Reiss’ expectancy theory of fear. This would include the content domains of injury, somatic reaction and interpersonal concerns, to study the underlying factorial structure, and to determine the test quality of the resulting subscales. Methods: A total of 555 regular dental patients answered the item pool. Subsamples filled in the Dental Anxiety Scale (DAS) (n = 346) and the Anxiety-Present Scale of the state-form of the State-Trait Anxiety Inventory (STAI-S) (n = 187). A second sample (n = 89) was used to determine test-retest reliability and bias for social desirability [Self Disclosure Scale of the Freiburg Personality Inventory (FPI)]. Results: Exploratory and confirmatory factor analyses identified a stable three-dimensional structure underlying the items convergent to the content domains of interpersonal, injury and somatic reaction concerns. Internal consistencies of the resulting subscales were between α = 0.84 and α = 0.87, test-retest reliabilities were from rtt = 0.72–0.78. No evidence for a social desirability response bias was found. All subscales discriminated between patients with low and high dental trait anxiety at a level of P

Polyphenols, phenolic acids, fibres and antioxidant capacity were determined in water, acetone and methanol extracts of buckwheat, rice, soybean, quinoa and 3 amaranth cultivars. Their antioxidant activities were comparatively assessed by total radical-trapping antioxidative potential (TRAP), ferric ion-reducing antioxidant power (FRAP), cupric-reducing antioxidant capacity (CUPRAC) and nitric oxide (NO center dot) assays, which comprised of contributions from polyphenols and phenolic acids (especially from the most abundant ferulic acid). The correlation coefficients between polyphenols and antioxidant activities of cereal and pseudocereal methanol extracts with FRAP, NO center dot, CUPRAC and TRAP were 0.99, 0.97, 0.96 and 0.77, respectively. The weakest correlation was with dietary fibres, an average one exhibited with tannins and marked correlation was shown with the phenolics. All the applied methods have shown that pseudocereals have higher antioxidant activity than some cereals (rice and buckwheat) and can be successfully replaced by cereals in case of allergy.

The aim of the study was to investigate the reactive oxygen species (ROS) production in the hypoxanthine–xanthinoxidase (HX–XO), hydrogen peroxide–ferrous sulphate (H 2 O 2 –FeSO 4 ) and hydrogen peroxide (H 2 O 2 ) systems by usingvarious concentrations of ROS scavengers, such as superoxide dismutase (SOD), dimethylthiourea (DMTU) or catalase (CAT).Luminol (0.8 mmol/L) was dissolved in a borate buffer, pH 9.0, and was used as a luminophor in the chemiluminescence (CL)measurements. In the HX–XO system SOD, CAT and DMTU deepened the CL signal, whereas in the H 2 O 2 –FeSO 4 system, onlyCAT and DMTU deepened the CL signal, and in the H 2 O 2 system SOD and CAT increased and DMTU deepened the CL signal.Electron spin resonance (ESR) measurements were performed only in the H 2 O 2 –FeSO 4 system. 5,5-dimethyl-pyrroline-N-oxide(DMPO) was used as a spin trap. According to typical ESR spectra, . OH was produced in this chemical system. It can be con-cluded that the chemical systems do not produce single reactive oxygen species but a mixture of them. Copyright © 2006 JohnWiley & Sons, Ltd.KEYWORDS: chemiluminescence; superoxide anion radical; hydroxyl radical; hydrogen peroxide

Dietary fibre, total polyphenols and phenolic acids in Spanish apples, peaches and pears were analysed and compared with their total radical-trapping antioxidative potential (TRAP). There were no significant differences in the content of dietary fibre among the studied fruits. The content of total polyphenols was 2.4 � 0.4, 2.1 � 0.3 and 6.9 � 0.7g kg � 1 in peeled fruits and 4.7 � 0.4, 4.5 � 0.4 and 11.1 � 1.2g kg � 1 in their peels for peaches, pears and apples respectively. The contents of dietary fibre, total polyphenols, caffeic, p-coumaric and ferulic acids and the TRAP values were significantly (P

The aim of the study was to examine the phagocyte-derived production of reactive oxygen species (ROS), lipoperoxidation and the total radical-trapping antioxidant parameter (TRAP) in patients undergoing regular haemodialysis (HD) followed by kidney transplantation (n = 13). A significant increase in both spontaneous and activated ROS generation was found during the post-transplantation period in days 1-3. This effect was caused mainly by an increased number of neutrophils. On the other hand, the TRAP parameter was decreased in HD patients. After kidney transplantation, the TRAP parameter increased, reaching the level of healthy controls at the end of the first week after surgery. Increase in MDA level was determined after HD and kidney transplantation. It can be concluded from the results obtained that phagocyte mobilisation and increased oxidative stress after HD and kidney transplantation were associated with the insufficient activity of extracellular antioxidant mechanisms resulting in increased lipid peroxidation.

An improved method for the preparation of leucocyte-rich plasma from human blood samples for chemiluminescence (CL) analysis is described. Heparinized blood is layered over 4% dextran in a ratio of 1 : 1 (v/v). The leucocyte-rich plasma is obtained after a 1 h sedimentation of the erythrocytes. When compared with the plasma obtained by the usual method of mixing blood with dextran, the residual red cell count was reduced. On the other hand, the index of phagocytosis (peak values of activated phagocytosis/spontaneous phagocytosis) was increased. This is caused by increased spontaneous CL activity after mixing blood with dextran, which can activate leucocytes. Such activation was observed both in plasma samples and in whole blood samples when measured immediately after dextran addition or after 1 h incubation with dextran.

The aim of the study was to test the effect of experimental conditions such as light radiation and temperature on chemiluminescence (CL) of 10(-2)-10(-5) mol/L lucigenin dissolved in various types of solvents. Irradiation by UV light (280, 297, 313 or 400 nm) induced a significant increase in CL of lucigenin dissolved in borate buffer. This effect was the most obvious for 10(-2)-10(-3) mol/L lucigenin. All wavelengths used had a similar effect. UV irradiation did not induce changes in the CL activity of lucigenin dissolved in dH2O or in dimethyl sulphoxide (DMSO). Different results for various solvents were not dependent on pH. The CL activity of 10(-2) mol/L and 10(-3) mol/L lucigenin dissolved in borate buffer increased depending on the solution temperature (25 degrees C, 30 degrees C, 37 degrees C or 40 degrees C) already at the beginning of the analysis, with a further increase during 16 h incubation period. It can be summarized that temperatures higher than 25 degrees C and intensive light irradiation are among those factors which significantly affect the result of analysis when lucigenin is used as a luminophor.