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Liu Ting - - 2004
Voltammetric behavior of dopamine (DA) on a gold electrode modified with the self-assembled monolayer (SAM) of N-acetylcysteine has been investigated, and one pair of well-defined redox peaks of dopamine is obtained at the SAM modified gold electrode. The oxidation peak current increases linearly with the concentration of dopamine in the ...
Tselepidis Stavros - - 2004
OBJECTIVE: This article describes conditions of ischemia and reperfusion in dog's liver. The aim of the study was to observe hepatic injury from oxygen free radicals and to evaluate mannitol and ascorbic acid as scavengers. METHODS: The criteria for evaluation were histopathological and biochemical. Twenty-one dogs were divided into three ...
Raschke T - - 2004
We present here a new cosmetic formula system containing 3% ascorbic acid based on an optimized oil-in-water (O/W) emulsion. This formulation demonstrated a good long-term stability of the active ingredient and also of the emulsion itself. It could be deduced from in vitro release studies that this O/W emulsion enabled ...
Kleinwächter Maik - - 2004
Up to now, a wide array of methods for the determination of myrosinase activity has been described. These vary from the simple photometric estimation to highly sophisticated assays using radioactively labelled substrates. However, ascorbic acid--an effective activator of myrosinases--interferes with most of these enzyme tests. Unfortunately, in the past, such ...
Sen Gupta Ronojoy - - 2004
Cadmium (Cd) is one of the environmental pollutants affecting various tissues and organs including testis. Harmful effect of Cd in testis is known to be germ cell degeneration and impairment of testicular steroidogenesis. Animals treated with high doses of Cd (0.2 and 0.3 mg/100g BW) showed a significant decrease in ...
Pan Chuan-Ju G - - 2004
The toxicity of diesel exhaust particles (DEP) can be due to the particle itself, extractable components, or both. Many studies focus on the biological properties of DEP-extractable components although it is possible that chemical properties inherent to the DEP itself can lead to toxicity. Thus, an examination of the chemistry ...
Ertl Siegmund - - 2004
A new, low-temperature sealed tube technique for combustion of organic carbon prior to subsequent off-line isotope analysis is proposed. Complete oxidation is achieved with potassium peroxodisulfate and silver permanganate as oxidants at temperatures not exceeding 500 degrees C. The combustion of gaseous (methane), solid (cane sugar, vanilla, N-thiazolyl-2-sulfamide, ascorbic acid, ...
Oladipo A - - 2004
This paper reports the effect of various concentrations of ascorbic acid on the availability of Fe, Zn, Ca and Mg in two popular plant foods--cowpea and amaranthus vegetable--in Nigeria. Ascorbic acid enhancement of iron availability was over 300 % and zinc by 200 % from 0-100 mg concentration. Availability of ...
Maurice D V - - 2004
1. An experiment was conducted with two strains of layers to ascertain whether the reduction in eggshell strength occurring at the end of the production cycle is the result of reduced ascorbic acid biosynthesis. 2. Hens producing strong and weak eggshells were identified within each strain and egg production, egg ...
Kraus Virginia B - - 2004
OBJECTIVE: To determine whether ascorbic acid might be of benefit for the treatment of spontaneous osteoarthritis (OA) when administered over a long period of time. METHODS: We investigated the effects of 8 months' exposure to low, medium, and high doses of ascorbic acid on the in vivo development of histologic ...
Gong Jing-Ming - - 2004
A novel and effective approach to sensitively determine serotonin, known as 5-hydroxytryptamine (5-HT), has been proposed based on a 5,5-ditetradecyl-2-(2-trimethylammonioethyl)-1,3-dioxane bromide (DTDB) self-assembled lipid bilayer membrane modified glassy carbon electrode (DTDB/GCE). A DTDB/GCE shows the strong electrocatalysis for the oxidation of 5-HT, with the peak potential shifted to less positive ...
Jagetia G C - - 2004
PURPOSE: Because of the crucial practical importance of acute radiation exposure associated with combined injuries, the study was undertaken to investigate the effect of various doses of ascorbic acid on the survival and healing of wounds in mice exposed to whole-body gamma-radiation. MATERIALS AND METHODS: Animals were given double-distilled water ...
Szymula M - - 2004
The antioxidant efficiency of two hydrophilic species, ascorbic acid (AA) and propyl gallate (PG), in an anionic surfactant system are studied. Ascorbic acid and propyl gallate are dissolved/solubilized in a microemulsion formed by water, pentanol, and sodium dodecyl sulfate. The determination of propyl gallate decomposition/oxidation kinetics shows enhanced oxidation of ...
Ishikawa Satoshi - - 2004
BACKGROUND: Periodontal ligament (PDL) cells form mineralized nodules in vitro. Ascorbic acid is known to be required in this process, although its effect on osteoblastic differentiation of PDL cells remains unclear. The purpose of this study was to determine the role of ascorbic acid on the early osteoblastic differentiation of ...
Goodpaster John V - - 2004
Low explosives such as smokeless powder, black powder, and black powder substitutes have been used in illicit pipe bombings throughout the United States. Some of the newer black powder substitutes are formulated with ascorbic acid, which gradually decomposes as the powder ages, making it difficult if not impossible for the ...
Hamlet Colin G - - 2004
The effect of dough recipe ingredients and processing on the generation of monochloropropanediol isomers (MCPDs) in leavened wheat doughs has been investigated. Commercial ingredients having no effect on MCPD formation were acetic acid and baking fats (triacylglycerols). Ingredients making a significant contribution to MCPD levels were yeast and flour improver ...
Toyoda-Ono Yoshiko - - 2004
A novel stable precursor of ascorbic acid (vitamin C), 2-O-(beta-D-glucopyranosyl)ascorbic acid, was isolated from both the ripe fresh fruit and dried fruit of Lycium barbarum L., a plant of the Solanaceae family. The chemical structure was inferred by instrumental analyses and confirmed by chemical synthesis. The dried fruit of Lycium ...
Tsivgoulis Gerasimos M - - 2004
Ascorbic acid in the presence of a catalytic amount of iodine reduces arsenic acid in methanol giving the arsenious acid bound to the 2-methyl hemi-ketal of dehydroascorbic acid, 5, in 1:1 and in a more stable 2:1 5/As(III) molar ratio. Removal of the As(III) and treating the 2-methyl hemi-ketal of ...
D'Amico Maria Lucia - - 2004
The effect of irrigation with 20% sea water was studied in 14 and 21-day-old seedlings of durum wheat (Triticum durum, cv. Ofanto). Comparisons between control (Hoagland's 2 solution) and treated (20% sea water in Hoagland's solution) plants included, besides HPLC determination of reduced (DHLA) and oxidised (LA) forms of lipoic ...
Ohta Yoshiji - - 2004
We examined whether short-term ascorbic acid deficiency impairs antioxidant status in the lens of guinea pigs. Male guinea pigs aged 4 wk were given a scorbutic diet (20 g/animal per day) with and without ascorbic acid (400 mg/animal per day) in drinking water for 3 wk. The ascorbic acid-deficient group ...
Shapiro Michael P - - 2004
Bacillus subtilis spores were killed by CuCl(2)-ascorbic acid, chloride ions were essential for killing of spores, and spores with defective coats were killed more rapidly. CuCl(2)-ascorbic acid did not damage spore DNA, and spores killed by this reagent initiated germination. However, spores killed by CuCl(2)-ascorbic acid may have damage to ...
Nishizawa Chiho - - 2004
Photosensitizers newly developed for photodynamic therapy of cancer need to be assessed using accurate methods of measuring reactive oxygen species (ROS). Little is known about the characteristics of the reaction of singlet oxygen (1O2) with spin traps, although this knowledge is necessary in electron spin resonance (ESR)/spin trapping. In the ...
Badrakhan Curd-David - - 2004
We present a fast to perform spectrophotometric method for the quantification of ascorbic acid and its oxidized form dehydroascorbic acid in biological samples. The assay detects a chromophore formed during the reaction of dehydroascorbic acid with methanol in phosphate/citrate buffer. This reaction can also be employed for the determination of ...
Passage Edith - - 2004
Charcot-Marie-Tooth disease (CMT) is the most common hereditary peripheral neuropathy, affecting 1 in 2,500 people. The only treatment currently available is rehabilitation or corrective surgery. The most frequent form of the disease, CMT-1A, involves abnormal myelination of the peripheral nerves. Here we used a mouse model of CMT-1A to test ...
Sezgintürk Mustafa Kemal - - 2004
In this study, an amperometric biosensor based on cucumber tissue homogenate was developed for the determination of glutathione. Cucumber (Cucumis sativus L.) tissue homogenate was used as the biological material. The cucumber tissue homogenate was cross-linked with gelatine using glutaraldehyde and fixed on a pretreated teflon membrane. The principle of ...
Ohta Yoshiji - - 2004
We examined whether short-term ascorbic acid deficiency induces oxidative stress in the retinas of young guinea pigs. Four-week-old guinea pigs were given a scorbutic diet (20 g/animal/day) with and without adequate ascorbic acid (400 mg/animal/day) in drinking water for 3 weeks. The serum concentrations of the reduced form of ascorbic ...
Balet Antònia - - 2004
BACKGROUND: We evaluate the effects of multilayered bags vs ethylvinyl-acetate bags on peroxidate formation of various emulsions for all-in-one total parenteral nutrition solutions (TPN) during storage. METHODS: Twenty-four parenteral nutritions were prepared with 4 commercial i.v. lipid emulsions (Soyacal 20%, Grifols; Intralipid 20%, Fresenius-Kabi; Lipofundina 20%, Braun; and Clinoleic 20%, ...
Lee Jun-Beum - - 2004
Efficiency was examined of microencapsulating L-ascorbic acid by polyglycerol monostearate (PGMS), and changes in the chemical and sensorial aspects of L-ascorbic acid and/or iron-fortified milk during storage were evaluated. The selected core materials were ferric ammonium sulfate and L-ascorbic acid. The highest efficiency (94.2%) of microencapsulation was found with the ...
Dimri U - - 2004
The aim of this study was to evaluate the therapeutic efficacy of commonly used acaricidal drugs in India and also to assess the effect of ascorbic acid as adjunct therapy in 72 growing sheep with sarcoptic mange, aged 5-6 months and weighing 20.4-31.7 kg. Eight replicates of nine animals were ...
Pérez-Ruiz Tomás - - 2004
A simple and rapid fluorimetric method for the determination of mixtures of thiamine and ascorbic acid is proposed. The procedure is based on the oxidation with mercury(II) of the B1 and C vitamins to form thiochrome (TC) and quinoxaline derivate, respectively. Both reaction products exhibit fluorescence at the same wavelengths ...
Tai Akihiro - - 2004
A series of novel lipophilic vitamin C derivatives, 6-O-acyl-2-O-alpha-D-glucopyranosyl-L-ascorbic acids possessing a branched-acyl chain of varying length from C(8) to C(16) (6-bAcyl-AA-2G), were evaluated as topical prodrugs of ascorbic acid (AA) with transdermal activity in a human living skin equivalent model. The permeability of 6-bAcyl-AA-2G was compared with those of ...
Kanikkannan N - - 2004
The present study was undertaken to prepare and evaluate monolithic drug-inadhesive type transdermal patches of melatonin containing penetration enhancers such as fatty alcohols, fatty acids, and terpenes. The patches were prepared using Eudragit E 100 as the adhesive polymer. The release profile of melatonin from control as well as enhancer-containing ...
Sahin N - - 2004
1. The effects of ascorbic acid (L-ascorbic acid) and melatonin supplementation on performance, carcase characteristics, malondialdehyde (MDA) as lipid peroxidation indicator, ascorbic acid, retinol, tocopherol and mineral status in the Japanese quail (Coturnix coturnix japonica) exposed to high ambient temperature were evaluated. 2. Two hundred and forty Japanese quails (10 ...
Bakaev V V - - 2004
Ascorbic acid plays a major role in pulmonary antioxidant defense. Sufficient amounts of ascorbic acid are necessary to maintain normal metabolic processes in the lung. We measured the levels of ascorbic, dehydroascorbic and diketogulonic acids in blood serum of patients with pulmonary tuberculosis (PTB) and pneumonia. The serum levels of ...
Deaton Christopher M - - 2004
The relationship between hydrogen peroxide (H2O2) concentration in expired breath condensate (EBC) and cytology of the respiratory tract obtained from tracheal wash (TW) or bronchoalveolar lavage (BAL), and epithelial lining fluid (ELF) antioxidant status is unknown. To examine this we analysed the concentration of H2O2 in breath condensate from healthy ...
Zhao Rong - - 2004
Ebselen is a selanazal drug recently revealed as a highly efficient peroxiredoxin mimic catalyzing the hydroperoxide reduction by the mammalian thioredoxin system [thioredoxin (Trx), thioredoxin reductase (TrxR), and NADPH]. The mammalian Trx system is a dehydroascorbic acid reductase recycling ascorbic acid essential for cell functions. Here we report that ebselen ...
Tao Y - - 2004
It is known that alpha-tocopherol (vitamin E) and L-ascorbic acid (vitamin C) can modulate many biochemical processes intracellularly or extracellularly as antioxidants. The objective of the present study was to investigate the effects of alpha-tocopherol and L-ascorbic acid on porcine oocyte meiotic maturation, viability and the functions of cumulus cells. ...
Barros Paulo S M - - 2004
BACKGROUND: Cataract is an important cause of blindness in dogs and frequently develops in young animals of certain breeds, such as the English cocker spaniel and the poodle. Protein oxidation is one of the mechanisms involved in lens opacification and may be causally related to depleted or diminished endogenous antioxidant ...
Fite Alemu - - 2004
It has been hypothesized that dietary nitrite augments the antimicrobial activity of gastric acid after conversion to nitric oxide and other reactive nitrogen intermediates, thus resulting in increased resistance against gastrointestinal infection. In this study, we showed that the reducing agents ascorbic acid and glutathione reduced the activity of acidified ...
May James M - - 2004
Recycling of ascorbic acid from its oxidized forms helps to maintain the vitamin in human erythrocytes. To determine the relative contributions of recycling from the ascorbate radical and dehydroascorbic acid, we studied erythrocytes exposed to a trans-membrane oxidant stress from ferricyanide. Ferricyanide was used both to induce oxidant stress across ...
Gum Elizabeth T - - 2004
BACKGROUND AND PURPOSE: Studies using animal models of stroke have shown that human serum albumin (HSA) significantly ameliorates cerebral ischemic injury after both transient and permanent ischemia, even when administered after the onset of ischemia or reperfusion. The mechanism of this effect remains uncertain, and prior studies suggest both indirect ...
Lee Jong-Suk - - 2004
This study presents a new approach that can stabilize effectively L-ascorbic acid in water-in-oil-in-water (w/o/w) double emulsions. Basically, the behavior of L-ascorbic acid in the aqueous phase was observed, considering its molecular deformation. Then, it was found that the stability determined in the aqueous phase by high-performance liquid chromatography (HPLC) ...
Das Kusal K - - 2004
We studied the effect of oral treatment with ascorbic acid (50 mg/100 g body weight) on nickel sulfate-induced (2.0 mg/100 g body weight, i.p.) alteration of nucleic acids and total protein concentration in the liver of Wistar strain male albino rats. Nucleic acids and total protein concentrations in treated rats ...
Dao Thanh H - - 2004
Animal manure contains partially digested feed fiber and grains where phosphorus (P) is bound in organic compounds that include myo-inositol 1,2,3,5/4,6-hexakis dihydrogenphosphate or phytic acid (IP6). Information is needed on the effects of other (non-IP6) organic ligands (LIGND) on the enzymatic dephosphorylation of IP6, which is a potential source of ...
Dakhale Ganesh - - 2004
There is evidence to suggest the derangement of the oxidant and antioxidant defense system in schizophrenia. The present study examined the effect of atypical antipsychotics on lipid peroxidation, superoxide dismutase (SOD) and ascorbic acid. For this purpose, a prospective, open-label, 8-week study design was utilized. Serum SOD, serum malondialdehyde (MDA) ...
Sarin Renu - - 2004
The callus tissue of Tagetes erecta maintained on revised Murashige and Skoog's medium (RT) as static cultures showed the presence of insecticidal pyrethrins. The percentage of pyrethrins further increased by feeding the tissue with various concentrations of ascorbic acid. The maximum pyrethrin content (1.68%) was observed in 6 weeks old ...
Pokorski M - - 2004
This study aims to compare the electron spin resonance (ESR) spectra emitted by human blood loaded with either ascorbyl-6-palmitate (AP), a lipid-soluble derivative of ascorbic acid (AA), or with AA. Whole blood of a healthy male individual was equilibrated with equimolar concentrations of AP and AA of 200, 400, and ...
Myojin Chiho - - 2004
Vegetables are rich source of antioxidative components such as ascorbic acid and polyphenols, which scavenge free radicals and reactive oxygen species and prevent life-style related diseases. In this work, the changes of radical-scavenging activity in shredded red and green cabbage leaves during storage were determined as well as ascorbic acid ...
Tada Mika - - 2004
BACKGROUND: A nitroxide radical, 4-hydroxyl-2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPOL), is directly reduced to hydroxylamine by ascorbic acid (AsA). Ascorbic acid is oxidized to dehydroascorbic acid (DHA) by ascorbic acid oxidase (AAOx), and DHA is reduced to AsA by glutathione (GSH). In the present study, in vivo and ex vivo reduction of TEMPOL in ...
Lee Soo-Bok - - 2004
Glycosylated ascorbic acids were synthesized by using the transglycosylation activity of Bacillus stearothermophilus maltogenic amylase with maltotriose to show effective antioxidative activity with enhanced oxidative stability. The modified ascorbic acids comprised mono- and di-glycosyl transfer products with an alpha-(1,6)-glycosidic linkage. The antioxidative effects of the glycosyl derivatives of ascorbic acid ...
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