Search results for "Smut"

Uncoupling of Endothelial Nitric Oxide Synthase in Cardiovascular Disease and its Pharmacological Reversal

2010

Publisher Summary This chapter discusses the role of oxidative stress in vascular dysfunction and atherogenesis, and strategies for its prevention. Endothelial dysfunction and oxidative stress have been identified as a common denominator of many cardiovascular risk factors. They support pro-inflammatory, prothrombotic, proliferative, and vasoconstrictor mechanisms that are involved in the initiation, progression, and complications of atherosclerosis. The pathophysiologic causes of oxidative stress involve changes in a number of different enzyme systems. Increased production of ROS by uncoupled eNOS is likely to contribute significantly to vascular oxidative stress and endothelial dysfunctio…

A new improved synthesis of the 110 K bismuth superconducting phase: freeze-drying of acetic solutions

1992

Abstract Metastability has greatly hindered the separated synthesis of the high-temperature superconducting phases represented as (Bi1−x, Pbx)2Sr2Can−1CunO4 + 2n (n = 2, 2-2-1-2, Tc≈80 K, and n = 3, 2-2-2-3, Tc≈110 K). By careful control of the synthetic variables, it becomes possible to obtain the 110 K phase as the only superconducting one through processing of freeze-dried acetic solutions. This technique leads to homogeneously sized (5–10 μm) micaceous platelets of the superconducting material.

Chronic Lymphocytic Leukemia: Correlations Between Oxidative Stress Metabolism and Cytogenetic Subgroups

2008

Abstract The chronic lymphocytic leukemia (B cell-CLL) is a heterogeneous lymphoproliferative disorder susceptible to oxidative stress. The excessive production of reactive oxygen intermediates above the capability of naturally produced antioxidants may result in the instability of essential macromolecules, and represents the molecular basis of many diseases including cancer. Highly reactive radicals interact with DNA inducing a multitude of oxidative modifications, and are implicated in mutagenesis due to misreplication of the damaged base 8-oxo-2′-deoxiguanosine (8-oxo-dG). Furthermore, protooncogene activation and/or tumor suppressor gene inhibition has been reported as a consequence of …

Oxidative stress and enzymatic antioxidant mechanisms in essential hypertension

2001

Age-related changes in antioxidant status and oxidative damage to lipids and dna in mitochondria of rat liver

2005

To investigate the correlation between oxidative stress and mitochondrial damage with aging, antioxidant system, levels of oxidative DNA damage and as an index of the loss of plasma membrane integrity lipid peroxidation and membrane potential were studied. Results showed that the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase significantly decreased during aging, however glutathione peroxidase (GSH-PX) increased in the aged mitochondria and glutathione (GSH) did not change during aging. No statistical difference was observed in the lipid peroxidation of mitochondria between young and old animals. The level of oxidative DNA damage (measured as 8oxo-dG) tended to in…

Sex Differences in Mitochondrial Antioxidant Gene Expression

2020

Females live longer than males. This could be in part due to the higher levels of estrogens in females, which protect them against aging. Physiological concentrations of estrogens have antioxidant effects as they induce the expression of manganese superoxide dismutase and glutathione peroxidase by stimulating estrogen receptors and the mitogen-activated protein kinase and nuclear factor kappa B pathways. However, estrogens can have undesirable effects such as they are feminizing to males, so other alternatives need to be searched. Phytoestrogens are good candidates as they can also bind to estrogens receptors, and in fact, they are able to mimic the antioxidant properties of estrogens. It i…

Exercise as an antioxidant: it up-regulates important enzymes for cell adaptations to exercise

2006

Abstract Aims. – To assess the role of the reactive oxygen species (ROS) in cell signalling and in the regulation of gene expression. Methods. – Exercise causes oxidative stress only when exhaustive. Strenuous exercise causes oxidation of glutathione, release of cytosolic enzymes, and other signs of cell damage. We have tested this hypothesis by studying the effect of inhibition of ROS production by allopurinol (an inhibitor of xanthine oxidase, a free radical generating enzyme) on cell signalling pathways in marathon runners and in rats submitted to exhaustive exercise by running on a treadmill. Results. – Exercise caused an activation of NF-κB in lymphocytes from marathon runners which wa…

Effects of strength and endurance training on antioxidant enzyme gene expression and activity in middle-aged men

2007

This study was aimed at investigating the effects of a 21-week period of progressive strength or endurance training on peripheral blood mononuclear cells (PBMC) antioxidant enzyme gene expression and activity in healthy middle-aged untrained men. Strength (n=11) and endurance (n=12) training were performed twice a week, including resistance exercises to activate all the main muscle groups or cycle-ergometer pedaling, respectively. mRNA levels of catalase, glutathione peroxidase (GPx), mitochondrial superoxide dismutase (MnSOD) and cytosolic superoxide dismutase (CuZnSOD) were increased after 21 weeks of strength training, while endurance training induced significant changes only in MnSOD an…

TRIARYL-ARSINE, -STIBENE UND -BISMUTHINE MIT -OR, -NR2-UND -CHR-NMe2-GRUPPEN IN ORTHO-STELLUNG

1983

Abstract Ortho-lithiated alkyl-arylethers, N,N-dialkylarylamines and substituted N,N-dimethylbenzylamines prepared according reaction (1) are reacted with the halides of arsine, antimony and bismuth forming the expected triarylarsines, triarylstibines and triarylbismuthines. By double lithiation the bis-arsine 37 is obtained. Nach (1) hergestellte ortho-lithiierte Alkyl-arylether, N,N-Dialkylarylamine und substituierte N,N-Dimethylbenzylamine werden nach (3) mit Arsen, -Antimon-und Wismutchloriden in die entsprechenden Triarylarsine, Triarylstibine und Triarylbismuthine uberfuhrt. Nach Zweifachlithiierung ist das Bis-arsin 37 zuganglich.

Phase transitions and distortion of [BiCl6]3– octahedra in (C3H5NH3)3[BiCl6] – DSC and single-crystal X-Ray diffraction studies

2004

The DSC diagram of tris(allylammonium) hexachlorobismuthate(III), (C3H5NH3)3[BiCl6], revealed three anomalies at 152, 191 and 299 K. The structure of the salt was determined at 200 and 315 K, below and above the high-temperature phase transition at 299 K. In both phases the crystals are monoclinic. At 200 K the space group is C2/c whereas at 315 K it is C2/m. The structures, at both temperatures, are composed of [BiCl6]3− octahedra and allylammonium cations. The organic and inorganic moieties are attracted to each other by a network of the N-H. . .Cl hydrogen bonds. The relationship between corresponding parameters of the unit cells has been found. The phase transition at 299 K, of the orde…