Search results for " radical"

Inhibition of leukocyte functions by the alkaloid isaindigotone from Isatis indigotica and some new synthetic derivatives.

2001

The alkaloid isaindigotone (1a) and seven derivatives have been synthesized to study their influence on several leukocyte functions and the generation of inflammatory mediators. Isaindigotone (1a) was found to be a scavenger of superoxide generated either by the hypoxanthine/xanthine oxidase system or stimulated human neutrophils. Isaindigotone (1a) and its acetylated derivative (1b) also inhibited 5-lipoxygenase activity and leukotriene B(4) production in these cells, whereas none of the compounds affected degranulation. In RAW 264.7 macrophages stimulated with lipopolysaccharide, synthetic derivatives exerted higher inhibitory effects on prostaglandin E(2) (PGE(2)) and nitric oxide (NO) g…

The impact of humic and fulvic acids on the dynamic properties of liposome membranes: the ESR method

2013

This paper presents the results of research on the influence of two fractions of humic substances (HS): fulvic acids (FA) and humic acids (HA), as a function of concentration, on the liposome membranes formed from egg yolk lecithin (EYL). The concentration of HS in relation to EYL changed from 0% to 10% by weight. The influence of HS on various areas of membranes: interphase water-lipid, in the lipid layer just below the polar part of the membrane and in the middle of the lipid bilayer, was investigated by different spin labels (TEMPO, DOXYL 5, DOXYL 16). The study showed that HA slightly decreased the fluidity of the analyzed membranes on the surface layer, while FA significantly liquidate…

Cirrhotic patients with minimal hepatic encephalopathy have increased capacity to eliminate superoxide and peroxynitrite in lymphocytes, associated w…

2018

Patients with minimal hepatic encephalopathy (MHE) show increased oxidative stress in blood. We aimed to assess whether MHE patients show alterations in different types of blood cells in (a) basal reactive oxygen and nitrogen species levels; (b) capacity to metabolise these species. To assess the mechanisms involved in the altered capacity to metabolise these species we also analysed: (c) peroxynitrite formation and d) peroxynitrite reaction with biological molecules. Levels of reactive oxygen and nitrogen species were measured by flow cytometry in blood cell populations from cirrhotic patients with and without MHE and controls, under basal conditions and after adding generators of superoxi…

Primary radical termination and chain transfer in vinyl polymerization

1974

Modulation of longevity-associated genes by estrogens or phytoestrogens.

2008

Abstract Females live longer than males. We have shown that the higher levels of estrogens in females protect them against aging, by up-regulating the expression of antioxidant, longevity-related genes, such as that of selenium-dependent glutathione peroxidase (GPx) and Mn-superoxide dismutase (Mn-SOD). Both estradiol and genistein (the most abundant phytoestrogen in soybeans) share chemical properties which confer antioxidant features to these compounds. However, the low concentration of estrogens and phytoestrogens make it unlikely that they exhibit significant antioxidant capacity in the organism. Physiological concentrations of estrogens and nutritionally relevant concentrations of geni…

Monitoraggio dei marciumi radicali da Phytophthora nei vivai di piante ornamentali in Italia

2014

Pedagogia dell'odio e funzione educativa dei genitori: uno studio di diritto comparato su mafia e radicalizzazione jihadista

2016

L’indagine prendel’abbrivio da talune decisioni in materia di decadenza della potestà genitoriale/responsabilità genitoriale nei confronti di alcuni mafiosi,ritenuti inidonei a svolgere la funzione educativa nei confronti dei figli. Ci si interroga sui limiti alla discrezionalità genitoriale nell’esercizio della funzione educativa ed in particolare, in che termini si possano ritenere legittimi o meno quei contenuti educativi, che si manifestano sia mediante forme d’indottrinamento sia mediante condotte genitoriali suscettibili di emulazione, volti alla trasmissione – e conseguente interiorizzazione - di “valori”, schemi comportamentali e modelli cognitivi che si pongono in profondo e radica…

A new hyaluronic acid pH sensitive derivative obtained by ATRP for potential oral administration of proteins

2013

Atom transfer radical polymerization (ATRP) has been successfully employed to obtain a new derivative of hyaluronic acid (HA) able to change its solubility as a function of external pH and then to be potentially useful for intestinal release of bioactive molecules, included enzymes and proteins. In particular, a macroinitiator has been prepared by linking 2-bromo-2-methypropionic acid (BMP) to the amino groups of ethylenediamino derivative of tetrabutyl ammonium salt of HA (HA-TBA-EDA). This macroinititor, named HA-TBA-EDA-BMP has been used for the ATRP of sodium methacrylate (MANa) using a complex of Cu(I) and 2,2'-bipyridyl (Byp) as a catalyst. The resulting copolymer, named HA-EDA-BMP-MA…

Testosterone and oxidative stress: the oxidation handicap hypothesis

2007

Secondary sexual traits (SST) are usually thought to have evolved as honest signals of individual quality during mate choice. Honesty of SST is guaranteed by the cost of producing/maintaining them. In males, the expression of many SST is testosterone-dependent. The immunocompetence handicap hypothesis has been proposed as a possible mechanism ensuring honesty of SST on the basis that testosterone, in addition to its effect on sexual signals, also has an immunosuppressive effect. The immunocompetence handicap hypothesis has received mixed support. However, the cost of testosterone-based signalling is not limited to immunosuppression and might involve other physiological functions such as the…

An experimental manipulation of life-history trajectories and resistance to oxidative stress

2006

Optimal investment into life-history traits depends on the environmental conditions that organisms are likely to experience during their life. Evolutionary theory tells us that optimal investment in reproduction versus maintenance is likely to shape the pattern of age-associated decline in performance, also known as aging. The currency that is traded against different vital functions is, however, still debated. Here, we took advantage of a phenotypic manipulation of individual quality in early life to explore (1) long-term consequences on life-history trajectories, and (2) the possible physiological mechanism underlying the life-history adjustments. We manipulated phenotypic quality of a co…