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Gupta Shruti - - 2006
BACKGROUND: Fresh vegetable produce is abundant during the winter season in Punjab. It is an important source of vitamins and minerals in the Punjabi diet, but the availability of ascorbic acid and beta-carotene from the vegetables is altered to varying degrees when they are subjected to traditional household processing methods. ...
Wu Ka Lung - - 2006
Arsenic trioxide induces growth inhibition and apoptosis in multiple myeloma cell lines. Reducing glutathione by ascorbic acid may enhance the efficacy of arsenic trioxide. Here we report the results of an international multi-center study of arsenic trioxide in combination with ascorbic acid and dexamethasone as treatment for patients with advanced ...
Song Gyun Jee - - 2006
Ascorbic acid has recently been reported to protect sperm DNA from the damage induced by exogenous oxidative stress in vitro. But, there is no report on seminal ascorbic acid and sperm DNA fragmentation in infertile men. In this study, we asked whether sperm DNA damage correlates with seminal ascorbic acid ...
Sardar K K - - 2006
Nitrovasodilators-sodium nitroprusside (SNP; 10(-9)-10(-4) M) and 3-morpholino-sydnonimine (SIN-1; 10(-9)-10(-4) M) produced concentration-dependent relaxation of the fourth generation sheep pulmonary artery, preconstricted with 5-hydroxytryptamine (1 microM). Oxidizing agents [oxidized glutathione (GSSG, 1 mM) and CuSO4 (5 and 20 microM)] and reducing agents [dithiothreitol (DTT, 0.1 mM), ascorbic acid (1 mM) and ...
Mostafa T - - 2006
This work aimed to assess the relationship of seminal ascorbic acid levels with smoking in infertile males. One hundred and seventy men were divided into four groups: nonobstructive azoospermia [NOA: smokers (n = 20), nonsmokers (n = 20)]; oligoasthenozoospermia [smokers (n = 30), nonsmokers (n = 20)]; asthenozoospermia [smokers (n ...
Chang Soo Im - - 2007
Oxidative stress has been suggested to be a major cause of male reproductive failure. Here, we investigated whether arsenic, which impairs male reproductive functions in rodent models, acts by inducing oxidative stress. Male 8-week-old ICR mice were given drinking water containing 20 or 40 mg/l sodium arsenite with or without ...
Debolt Seth - - 2007
l-Ascorbate (vitamin C) has well-documented roles in many aspects of redox control and anti-oxidant activity in plant cells. This Botanical Briefing highlights recent developments in another aspect of l-ascorbate metabolism: its function as a precursor for specific processes in the biosynthesis of organic acids. The Briefing provides a summary of ...
Bonilla Ernesto - - 2006
The efficacy of melatonin, glutathione, serotonin, minocycline, lipoic acid and ascorbic acid in counteracting the toxicity of paraquat in Drosophila melanogaster was examined. Male Oregon wild strain flies were fed for 5 days with control food or food containing the test substance. They were transferred in groups of five to ...
Amako Katsumi - - 2006
Erythroascorbic acid (eAsA) is a five-carbon analog of ascorbic acid, and it is synthesized from D-arabinose by D-arabinose dehydrogenase (ARA) and D-arabinono-gamma-lactone oxidase. We found an NAD+-specific ARA activity which is operative under submillimolar level of d-arabinose in the extracts of Saccharomyces cerevisiae. The hypothetical protein encoded by YMR041c showed ...
Kim Yeong-Joon - - 2006
Au nanorods prepared by a photochemical method were used as seeds for the overgrowth of thin shell of gold by using a mild reducing agent, ascorbic acid at ambient conditions. The overgrowth rate along different crystal facets of the starting gold nanorods was regulated by the addition of polyallylamine. The ...
Gönüllü U - - 2006
Calcium ascorbate (CAAS), which is a hydrophilic and stable derivative of ascorbic acid (vitamin C) (AA), is commonly used in foods as an antioxidative agent. There are very limited reports on its dermatological use in the literature. In this paper, it is reported that CAAS could be used in place ...
Gazivoda Tatjana - - 2007
The novel C-5 substituted uracil derivatives of l-ascorbic acid were synthesized by coupling of 5-iodouracil-4,5-didehydro-5,6-dideoxy-l-ascorbic acid with unsaturated stannanes under Stille reaction conditions. The new compounds were evaluated for their antitumoral and antiviral activities. Among all compounds evaluated the 5-propynyl substituted uracil derivative of l-ascorbic acid (7) exhibited the most ...
Soltés Ladislav - - 2006
The degradation of high-molar-mass hyaluronan (HA) by copper(II) chloride and ascorbate was studied by means of rotational viscometry. It was found that even small amounts of CuCl(2) present in the oxidative system led to the pronounced degradation of HA, reflected in a rapid decrease of the dynamic viscosity of the ...
Nassef Hossam M - - 2007
The direct and selective detection of ascorbate at conventional carbon or metal electrodes is difficult due to its large overpotential and fouling by oxidation products. Electrode modification by electrochemical reduction of diazonium salts of different aryl derivatives is useful for catalytic, analytical and biotechnological applications. A monolayer of o-aminophenol (o-AP) ...
Iqbal M Perwaiz - - 2006
Fresh fruits and vegetables are good sources of vitamin C which is known for its antioxidant and immune-enhancing effects. The objective of this study was to determine ascorbic acid (vitamin C) contents of regularly consumed fruits and vegetables available in Pakistani markets. Most commonly used fresh fruits and vegetables were ...
Heras Jorge Yánez - - 2007
The sequential electrochemical polymerization of aniline and N-(3-propane sulfonic acid)aniline (PSA) is proposed to construct a sensor able to detect ascorbate at physiological conditions. Compared to poly(aniline) modified electrode, a device with improved conducting and electrochemical properties at neutral pH is obtained. The electrochemical copolymerization of the same starting materials ...
Davaran Soodabeh - - 2006
The present study was conducted to investigate the effect of poly(ethylene glycol)-alpha-cyclodextrin (alpha-CD) complexes on stabilization and cutaneous permeation of ascorbic acid from specially prepared transdermal patches. Poly(ethylene glycol) citrate (6-armPEG) and its inclusion complex with alpha-CD were prepared and used for preparation of the transdermal patches. Duro-Tak 87-2979 was ...
Helms Steve - - 2006
Chronic rhinosinusitis (CRS) is one of the most common long-term illnesses in the United States, affecting approximately 14 percent of the population. CRS is a challenging condition to treat, partly due to its multifaceted, poorly understood pathophysiology. Treatment goals include maintaining open drainage and decreasing inflammation while improving tissue integrity ...
Tworoger Shelley S - - 2006
The measurement of biomarkers in blood specimens has become an integral component of many epidemiologic studies and introduces several decision points about specimen collection, processing, and storage for the investigator. We briefly discuss the current state of knowledge for four commonly assessed biomarkers: estrogens and other sex hormones, ascorbic acid ...
Deaton C M - - 2006
REASONS FOR PERFORMING STUDY: Following a period of airway inflammation the clearance of inflammatory cells along the mucociliary escalator may impose a considerable oxidant load on the trachea. OBJECTIVES: To determine the degree of oxidative stress in tracheal epithelial lining fluid (ELF) in comparison to that present in peripheral airways ...
Görner Helmut - - 2006
The photolysis of 9,10-anthraquinone (AQ), 2-methyl- and 2,3-dimethyl-AQ was studied in air-saturated acetonitrile-water in the presence of various donors: formate, ascorbic acid, alcohols, e.g. 2-propanol or methanol, and amines, e.g. ethylenediaminetetraacetate (EDTA). The photoreaction is initiated by H-atom or electron transfer from the donor to the AQ triplet state. The ...
Schlieve Christopher R - - 2006
Retinal ganglion cells (RGCs) undergo apoptosis after axonal injury, in part regulated by an intracellular superoxide anion burst, for which the target(s) are unknown. Shifting the RGC redox state towards reduction and preventing sulfhydryl oxidation is neuroprotective in vitro and in vivo, implying that one or more sulfhydryls on one ...
Latkowska E - - 2006
The influence of (+)-usnic acid on rates of gas exchange (photosynthesis, respiration, and transpiration) in long-term cultivation of tomato plants was studied. The effect was dose-dependent. Plants grown in media containing the maximum concentration of (+)-usnic acid (30 muM) had photosynthetic and respiration rates reduced by 41% and 80%, respectively. ...
Hsieh Hsin-Ju - - 2006
The surface of a lipase from Burkholderia cepacia was coated with a nonionic surfactant, propylene glycol monostearate, and was used as a biocatalyst in the production of ascorbic acid in tert-butyl alcohol. The influence of various factors such as the type of surfactant, the pH of the buffer used for ...
Liu Jianhua - - 2007
A kinetic method performed on a flow injection system is described for the determination of ascorbic acid by using its catalytic effect on the complexation reaction of Cu(II) with 5,10,15,20-tetrakis(4-N-trimethyl-aminophenyl)porphyrin. The characteristic spectrum of porphyrin (Soret band), which shows intense absorption around 400 nm (epsilon>2.0 x 10(5) cm(-1)M(-1)), was used ...
Jeong Yeon Woo - - 2006
The objective was to determine optimal concentrations of alpha-tocopherol and l-ascorbic acid for development of porcine embryos derived from in vitro-fertilization (IVF) or somatic cell nuclear transfer (SCNT). The frequency of blastocyst formation in IVF embryos was 17.6, 28.6, 32.4 and 21.4% for control, 50, 100 and 200microM alpha-tocopherol, respectively, ...
Hossein Mohammad Shamim - - 2007
The susceptibility of embryos to reactive oxygen species (ROS) varies in different stages of embryo development. The present study evaluated temporal effects of alpha-tocopherol and L-ascorbic acid on the porcine embryo development, and investigated whether a single or twice supplements of these two antioxidants at a divided concentrations favors the ...
Guijarro B - - 2007
Stabilizers were added to conidia of Penicillium frequentans at two different points of the production-formulation process to improve shelf-life of conidia stored at different temperatures. Effects were also tested on conidial germination and production. Germination of conidia without additives was 90.2%; sodium chloride, potassium chloride, triton TX100, dimethyl sulphoxide, peroxidase, ...
Tai Akihiro - - 2006
2-O-alpha-D-glucopyranosyl-6-O-hexadecanoyl-L-ascorbic acid (6-sPalm-AA-2G), a novel stable lipophilic ascorbic acid derivative, was hydrolyzed to 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G), ascorbyl 6-palmitate (6-sPalm-AA) and ascorbic acid (AA) with alpha-glucosidase and lipase. An HPLC method for the simultaneous determination of AA, AA-2G, 6-sPalm-AA and 6-sPalm-AA-2G was developed using a cyanopropyl column with an isocratic solution ...
Van Opstal I - - 2006
AIMS: To study the bactericidal properties of the lactoperoxidase (LPER)-thiocyanate and soybean peroxidase (SBP)-thiocyanate systems at low pH, their efficiency for inactivation of Escherichia coli and Shigella in acidic fruit and vegetable juices, their effect on colour stability of the juices and interaction with ascorbic acid. METHODS AND RESULTS: Three-strain ...
Senthil Kumar Sellappan - - 2006
A new approach was attempted to prepare a chemically modified electrode using Cobalt hexacyanoferrate (CoHCF) as the redox mediator and to study its stability and electrocatalytic activity for ascorbic acid (AA) oxidation. The basic principle underlying the electrode modification is the coordination of cobalt ion with the amino nitrogen of ...
Martínez Luis - - 2006
The effects of rosemary, in combination with ascorbic acid, red beet root, and sodium lactate, as well as their mixtures, on the inhibition of both lipid and pigment oxidation of fresh pork sausages packaged in a modified atmosphere were studied. Sausages (240) were packaged in a 80% O2 + 20% ...
Maia Adriana M - - 2007
HPLC stability-indicating method was validated for Vitamin C (ascorbic acid) in semisolid pharmaceutical/cosmetic formulations containing glutathione and sodium metabisulfite, as antioxidants. The described procedure included a reliable, precise, accurate and specific method determination employing a 250mm x 4.6mm C(18) column, 0.2% metaphosphoric acid/methanol/acetonitrile (90:8:2, v/v/v) as the mobile phase and ...
Urbano Nicoletta - - 2007
PURPOSE: A novel biotin-DOTA conjugate (r-BHD: reduced biotinamidohexylamine-DOTA) was investigated in order to provide an efficient pretargeted antibody-guided radioimmunotherapy (PAGRIT) application. Preclinical and clinical results are described. METHODS: (90)Y and (177)Lu were used to label r-BHD. The effect of pH and a wide range of specific activities were studied. Radiolabelled ...
Lee Kwang-Pill - - 2006
A self-assembly directed approach was adopted to modify glassy carbon electrode (GC) with gold nanoparticles incorporation and the electrocatalytic performance of self-assembly modified electrode, GC/SA-Au-ME was critically evaluated for the oxidation of ascorbic acid (AA). The modification involves the dispersion of multi-wall carbon nanotube (MWNT) and an inclusion complex, beta-cyclodextrin-4-aminothiophenol ...
Inoue Naoko - - 2006
The chemiluminescence of gallic acid by hydrogen peroxide had completely inhibited by the presence of ascorbate. After ascorbate had disappeared by oxidation, chemiluminescence returned. The concentration of gallic acid was virtually unchanged by presence of ascorbate, but started to decrease after the disappearance of ascorbate. This might be attributable to ...
Heber Geoffrey K - - 2006
BACKGROUND: Ascorbic acid has numerous essential and beneficial functions in normal and photoaged skin. Ionisation of ascorbic acid in aqueous topical formulations leads to oxidative degradation. Ascorbic acid in an anhydrous vehicle would inherently have greater stability. OBJECTIVE: The objective of this study was to observe the effects of two ...
Serrano María - - 2006
Table grapes (Vitis vinifera L. cv. Crimson Seedless) were coated with Aloe vera gel according to our developed patent (SP Patent P200302937) and then stored for 35 days at 1 degrees C, and the subsequent shelf life (SL) was monitored at 20 degrees C. Uncoated clusters showed a rapid loss ...
Wood Paul L - - 2006
The concept of "oxidative stress" has become a mainstay in the field of neurodegeneration but has failed to differentiate critical events from epiphenomena and sequalae. Furthermore, the translation of current concepts of neurodegenerative mechanisms into effective therapeutics for neurodegenerative diseases has been meager and disappointing. A corollary of current concepts ...
Bok Jung Hun - - 2006
Stripping voltammetry capable of detecting 0.3microg/L arsenate and arsenite was applied for speciation analysis of arsenic sorbed onto synthetic ferrihydrite, goethite at As/Fe ratio of approximately 1.5mg/g with or without birnessite after sequential extraction using 1M phosphate (24 and 16 h) and 1.2M HCl (1h). Precautions to avoid oxygen were ...
Martinello Flávia - - 2006
BACKGROUND: Ascorbic acid interferes negatively in peroxidase-based tests (Trinder method). However, the precise mechanism remains unclear for tests that use peroxide, a phenolic compound and 4-aminophenazone (4-AP). We determined the chemical mechanism of this interference, by examining the effects of ascorbic acid in the reaction kinetics of the production and ...
Hu Guangzhi - - 2006
A L-cysteine (L-Cys) self-assembled modified gold electrode was used to detect dopamine (DA) by chronoamperometric method (CE) in the presence of ascorbic acid (AA). The defective limit is 2.0 x 10(-8) mol L(-1) (S/N=3). The proposed method was applied to detect DA in the samples with satisfied result.
Shekhovtsova Tatyana N - - 2006
The feasibility and expediency of enzymatic methods application in food analysis is demonstrated by the example of ascorbic acid (AsA) determination in foods. Enzymatic determination of ascorbic acid is based on its action as a second substrate of horseradish (HRP) and peanut (PNP) peroxidases in the reactions of o-dianisidine (OD) ...
Kim Do-Sung - - 2006
Adriamycin is a potent antitumor drug that is known to cause severe cardiotoxicity. This study examined the protective effect of calceolarioside on adriamycin-induced cardiomyocyte toxicity. Calceolarioside significantly inhibited the adriamycin induced cell death and caspase-3 activation, which may be explained by the increase in Bcl-2 expression and the inhibition of ...
Kiyota Maki - - 2006
Plant defenses against photo-oxidative stress have been studied almost exclusively with respect to stress responses, and little is known about how non-enzymic antioxidants change under constant conditions without a time cue or an environmental stress. Here, we show that, in both the flagellated alga Euglena gracilis Z and the angiosperm ...
Ramalingam K - - 2006
The ascorbic acid level was highest in immature proglottides and lowest in gravid proglottides of Avitellina lahorea, the gut parasite of sheep. The ascorbic acid content in all the regions of the parasite viz., immature, mature and gravid taken together remained higher to the value of the host serum. The ...
Görner Helmut - - 2006
The photolysis of acetophenone, benzophenone, 4-carboxybenzophenone and benzil was studied in air-saturated aqueous solution in the presence of alcohols. The overall reaction is an oxidation of 2-propanol to acetone. The quantum yield of oxygen uptake (Phi(-O(2))) increases with increasing 2-propanol concentration up to 0.9. The photoreaction can also be initiated ...
Yogeeta Surinder Kumar - - 2006
The present study aims at evaluating the effect of the combination of ferulic acid and ascorbic acid on isoproterenol-induced abnormalities in lipid metabolism. The rats were divided into eight groups: Control, isoproterenol, ferulic acid alone, ascorbic acid alone, ferulic acid+ascorbic acid, ferulic acid+isoproterenol, ascorbic acid+isoproterenol and ferulic acid+ascorbic acid+isoproterenol. Ferulic ...
Paixão Thiago R L C - - 2006
A positionable platinum microelectrode fabricated by electrochemical etching was used to monitor the concentration of ascorbic acid in fruits and vegetables. Studies carried out with ascorbate oxidase confirmed the suitability of the amperometric sensor to measure selectively the ascorbic acid content. The results obtained with the proposed method for ascorbic ...
Tiitinen Katja M - - 2006
A fast, one-step gas chromatographic method was developed to analyze trimethylsilyl (TMS) derivatives of sugars, fruit acids, and ascorbic acid in sea buckthorn (Hippohaë rhamnoides L.) berries. The method was applied to berry press juice of sea buckthorn of different origins grown in Finland during the 2003 and 2004 seasons. ...
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