Decreased zinc availability affects glutathione metabolism in neuronal cells and in the developing brain.

A deficit in zinc (Zn) availability can increase cell oxidant production, affect the antioxidant defense system, and trigger oxidant-sensitive signals in neuronal cells. This work tested the hypothesis that a decreased Zn availability can affect glutathione (GSH) metabolism in the developing rat brain and in neuronal cells in culture, as well as the capacity of human neuroblastoma IMR-32 cells to upregulate GSH when challenged with dopamine (DA). GSH levels were low in the brain of gestation day 19 (GD19) fetuses from dams fed marginal Zn diets throughout gestation and in Zn-deficient IMR-32 cells.

Assessment of the antioxidant capacity of natural fruit extracts by inhibition of probe decay and plasma lipid peroxidation.

The oxidation of lipids, proteins, and DNA induced by reactive oxygen species has been implicated in the development of various diseases, and the role of antioxidants has received much attention. Free-radical scavenging antioxidants play an important role in the defense network in vivo, and assessment of the capacity of antioxidants has been the subject of extensive studies and controversy, but there is no universal method by which antioxidant capacity can be measured accurately. In the present study, the assessment of the antioxidant capacity of natural fruit extracts was examined for radical scavenging and inhibition of lipid peroxidation.

Action of 6-amino-3-pyridinols as novel antioxidants against free radicals and oxidative stress in solution, plasma, and cultured cells.

Free radical-mediated lipid peroxidation has been implicated in the pathogenesis of various diseases. Lipid peroxidation products are cytotoxic and they modify proteins and DNA bases, leading eventually to degenerative disorders. Various synthetic antioxidants have been developed and assessed for their capacity to inhibit lipid peroxidation and oxidative stress induced by free radicals.

Assessment of antioxidative activity of extract from fermented grain food mixture using chemical and cellular systems.

Fermented food is a rich source of antioxidants and micronutrients with the potential to prevent various human diseases. The increasing evidence indicates that in addition to its direct action, radical-scavenging antioxidants may modulate the cellular antioxidant system such as glutathione. In the present study, we investigated the antioxidant activity of Antioxidant Biofactor (AOB) extracts, a mixture of commercially available fermented grain food by using chemical and cellular experimental systems.

Characterization of novel furan compounds on the basis of their radical scavenging activity and cytoprotective effects against glutamate- and lipopolysaccharide-induced insults.

There is increasing evidence indicating that free radicals and oxygenases such as cyclooxygenase (COX) and lipoxygenase (LOX) are related to the onset and development of neurodegenerative diseases. In order to prevent and/or delay these diseases, the use of radical-scavenging antioxidants and inhibitors against oxygenases has received much attention. In the present study, we examined the radical-scavenging activity and cytoprotective effects of some novel furan compounds with potent inhibitory activity against oxygenases such as COX-1, COX-2, and 5-LOX.

Induction of adaptive response and enhancement of PC12 cell tolerance by lipopolysaccharide primarily through the upregulation of glutathione S-transferase A3 via Nrf2 activation.

Increasing evidence indicates that reactive oxygen species and other physiologically existing oxidative stimuli upregulate the antioxidant system, thereby triggering the adaptive response. In this study, we focused on adaptive cytoprotection induced by lipopolysaccharide (LPS), which induces oxidative stress and inflammatory cytokines, in PC12 cells, a model of the neuronal cell. After treating PC12 cells with LPS at sublethal concentrations, we found that they developed resistance to subsequent oxidative stress induced by 13S-hydroperoxy-9Z,11E-octadecadienoic acid and 5-amino-3-(4-morpholinyl)-1,2,3-oxadiazolium.

Assessment of radical scavenging capacity and lipid peroxidation inhibiting capacity of antioxidant.

The role of radical scavenging antioxidants against oxidative stress has received much attention, and the antioxidant capacity has been assessed by various methods. Among them, a method that measures the effect of antioxidant on decay of the probe is one of the most widely used methods. The present study was performed to compare the two methods to assess the antioxidant capacity, one to follow the decay of the probe and the other to measure lipid peroxidation products in human plasma.

Simple assessment of radical scavenging capacity of beverages.

The radical-scavenging antioxidants play an important role against oxidative stress in the defense system in vivo. The beneficial effects of antioxidants contained in foods and beverages have been well-accepted, and their antioxidant capacity has been assessed by various methods. In the present study, a simple method is proposed in which the total radical scavenging capacity is assessed from the bleaching of pyranine and pyrogallol red induced by free radicals generated from azo initiator.

Antioxidant capacity of BO-653, 2,3-dihydro-5-hydroxy-4,6-di-tert-butyl-2,2-dipentylbenzofuran, and uric acid as evaluated by ORAC method and inhibition of lipid peroxidation.

The role of radical-scavenging antioxidant against oxidative stress has received much attention. The antioxidant capacity has been assessed by various methods. Above all, oxygen radical absorbance capacity (ORAC) has been frequently employed [Prior et.

Interactions between stainless steel, shear stress, and monocytes.

Angioplasty with stent placement is commonly used to treat coronary atherosclerosis. However, 20-40% of stainless steel stents restenose within 6 months via a prolonged inflammatory response mediated by monocytic infiltration and cytokine secretion. In the current study, we tested a hypothesis that blood flow and monocytes interact to alter stent corrosion.

Effect of mercury(II) on Nrf2, thioredoxin reductase-1 and thioredoxin-1 in human monocytes.

Objectives: Human blood levels of mercury are commonly 10nM, but may transiently reach 50-75nM after dental amalgam placement or removal. Controversy persists about the use of mercury because the effects of these 'trace' levels of mercury are not clear. Concentrations of mercury > or =5000nM unequivocally alter redox balance in blood cells including monocytes.

Change of color and translucency by light curing in resin composites.

Objective: This study evaluated color and translucency changes caused by light curing resin composite materials.

Methods: The CIELAB parameters (L*, a* and b*) of disks of A2 and opaque A2 shades of Charisma (Heraeus-Kulzer), Solare (GC) and Filtek Supreme (3M) were evaluated on the backings of black, white and the material itself both before and after light curing to evaluate color and translucency changes (by means of calculating deltaE* and the translucency parameter, respectively).

Results: Solare and Filtek Supreme showed significantly smaller color changes during light curing than Charisma; however, the value of deltaE* of all the products/shades was still in the clinically unacceptable range.

Staining of hybrid composites with coffee, oolong tea, or red wine.

This study examined the surface staining mechanism of a photopolymerized composite by coffee, oolong tea, and red wine. Dental composite was subjected to an experimental 24-hour staining cycle: 17-hour immersion in artificial saliva solution containing 0.3% mucin followed by 7-hour immersion in coffee, tea, or wine.

Sublethal concentrations of diverse gold compounds inhibit mammalian cytosolic thioredoxin reductase (TrxR1).

Unlabelled: Thioredoxin reductase (TrxR) reduces thioredoxin (Trx), thereby contributing to cellular redox balance, facilitating the synthesis of deoxy-ribose sugars for DNA synthesis, and regulating redox-sensitive gene expression. Auranofin is a gold compound that potently inhibits TrxR. This inhibition is one suspected mechanism of auranofin's therapeutic benefit in the treatment of rheumatoid arthritis.

Gold-induced reactive oxygen species (ROS) do not mediate suppression of monocytic mitochondrial or secretory function.

Unlabelled: The toxicity of anti-rheumatic gold compounds has limited their use and development, yet both the toxicological and therapeutic actions of these compounds remain unclear. In the current study, we tested the hypothesis that intracellular reactive oxygen species (ROS) induced by Au(I) or Au(III) compounds mediate their ability to suppress mitochondrial activity.

Methods: Human THP1 monocytes were exposed to HAuCl(4) x 3H(2)O (Au(III)), or the anti-rheumatic compounds auranofin (AF) or gold sodium thiomalate (GSTM) for 6-72 h, after which mitochondrial activity (succinate dehydrogenase) was measured.

Extracellular environment as one mediator of blue light-induced mitochondrial suppression.

Objectives: The current study tested the hypothesis that the extracellular environment mediates mitochondrial suppression of oral epithelial cells and fibroblasts by blue light.

Methods: We exposed Balb fibroblasts (Balb), normal human epidermal keratinocytes (NHEK), and oral squamous carcinoma cells (OSC2) to blue light (30-120J/cm2) in different cell-culture media and in phosphate buffered saline (PBS). Mitochondrial activity (MTT method) was used to assess cellular response 72 h post-light exposure.

Colour and translucency of opaque-shades and body-shades of resin composites.

The purpose of this study was to evaluate the optical properties--not only the translucency but also the colours--of opaque-shade resin composites. The CIELAB parameters (L*, a* and b*) of disks of A2 and opaque A2 (OA2) shades of Charisma (Heraeus-Kulzer), Solare (GC) and Filtek Supreme (3M) were evaluated on backings of black, white and the material itself to calculate the translucency parameter (TP) and the colour differences (delta E*) between A2 and OA2. A two-way analysis of variance (anova) for the TP indicated a less statistically significant TP value in the OA2 shade than the A2 shade for all products.