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Lai Y L - - 1999
Antioxidants attenuate noncholinergic airway constriction. To further investigate the relationship between tachykinin-mediated airway constriction and oxygen radicals, we explored citric acid-induced bronchial constriction in 48 young Hartley strain guinea-pigs, divided into six groups: control; citric acid; hexa(sulphobutyl)fullerenes + citric acid; hexa(sulphobutyl)fullerenes + phosphoramidon + citric acid; dimethylthiourea (DMTU) + citric ...
Wong C H - - 1999
Citric acid has been used as a tussive agent in the investigation of the cough reflex. The mechanism of cough stimulation remains unclear. We conducted studies to compare the cough response of citric acid to an organic (acetic acid) and an inorganic acid (phosphoric acid). We also compared the cough ...
Xiong R - - 1999
The fate of Salmonella enteritidis PT4 in home-made mayonnaise prepared with citric acid solution (citric acid concentration of > or = 4.98% (w/v)) was investigated. It was found that pH of mayonnaise is closely related to the ratio of egg yolk to citric acid, and the inactivation rate of the ...
Cheung A K - - 1999
Although dialyzer reuse in chronic hemodialysis patients is commonly practiced in the United States, performance of reused dialyzers has not been extensively and critically evaluated. The present study analyzes data extracted from a multicenter clinical trial (the HEMO Study) and examines the effect of reuse on urea and beta2-microglobulin (beta2M) ...
Dowd P F - - 1999
The fungal metabolite kojic acid, which is produced by Aspergillus and Penicillium species fungi that may be pathogens of both insects and plants, was a significant inhibitor of phenoloxidase of different representative beetle and caterpillar insect species. Fusaric acid and picolinic acid, produced by Fusarium spp., were also significant inhibitors ...
Kirimura K - - 1999
Citric acid production from xylan and xylan hydrolysate was done by Aspergillus niger Yang no. 2 cultivated in a semi-solid culture using bagasse as a carrier. Yang no. 2 produced 72.4 g/l and 52.6 g/l of citric acid in 5 d from 140 g/l of xylose and arabinose, respectively. Yang ...
King B M - - 1998
In two profiling experiments and one grouping experiment, panelists evaluated orange drinks in order to measure the effects of design variables, especially color, on basic tastes as well as on more consumer-like attributes such as flavor strength and naturalness. Naturalness was increased in one experiment by lowering degrees Brix or ...
Takechi M - - 1998
Anti-washout-type fast-setting calcium phosphate cement using chitosan (aw-FSCPC(chi)), conventional CPC (c-CPC), CPC mixed with citric acid (CPC(citric)) and CPC mixed with polyacrylic acid (CPC(acrylic)) were implanted subcutaneously in rats immediately after mixing to shed some light on the understanding of the appearance of excellent tissue response to CPC. CPC(citric) and ...
Kondo T - - 1998
This study tested the hypothesis that the afferent input from the respiratory muscles may be involved in the neural mechanisms inducing cough responses. Coughing was evoked in conscious healthy humans by the inhalation of citric acid aerosol of several concentrations either during or not during chest wall vibration (100 Hz) ...
Rajashekhara E - - 1998
Heat-resistant molds, including Neosartorya fischeri, are known to spoil thermally processed fruit products. The control measures required for such problems must not cause an appreciable loss of the organoleptic qualities of the final products. In the present study we determined the thermal death rates of ascospores of N. fischeri ATCC ...
Cvetnić Z - - 1998
96 strains of Aspergillus flavus isolated from samples of stored grain and smoke-dried meat products were examined for ability to produce cyclopiazonic acid and aflatoxins, grown on mycological broth medium and malt extract agar. Five strains produced cyclopiazonic acid in the range of 0.5-30 mg/kg and 9 produced aflatoxin B1 ...
Tao L - - 1998
Optically gated capillary electrophoresis (CE) of amino acids derivatized with o-phthalaldehyde/β-mercaptoethanol (OPA/β-ME) was explored as a means to monitor amino acids with high temporal resolution. In agreement with a theoretical model described herein, 98% of a given concentration of OPA/β-ME derivatives can be photobleached by a few milliwatts of the ...
Zhike H - - 1998
A chemiluminescence method for the determination of citric acid was developed. The method is based on the enhancement of citric acid on the chemiluminescence light emission of tris-(2,2'-bipyridine)ruthenium(II). In the presence of tris-(2,2'-bipyridine)ruthenium(II), upon the addition of Ce(IV), resulted in intense light emission. The emission intensity is greatly enhanced by ...
Miyamoto T - - 1998
We examined the sour taste transduction mechanism in the mouse by applying whole cell patch-clamp technique to nondissociated taste cells from the fungiform papillae. Localized stimulation with 0.5 M NaCl and 25 mM citric acid (pH 3.0) of the apical membrane enabled us to obtain responses from single taste cells ...
Martin F - - 1998
The metabolism of [1-13C]glucose in Pisolithus tinctorius cv Coker & Couch, in uninoculated seedlings of Eucalyptus globulus bicostata ex Maiden cv Kirkp., and in the E. globulus-P. tinctorius ectomycorrhiza was studied using nuclear magnetic resonance spectroscopy. In roots of uninoculated seedlings, the 13C label was mainly incorporated into sucrose and ...
Schnierle P - - 1998
Singly charged amines and sulfonic acids as cationic and anionic aliphatic model substances, respectively, were detected in capillary electrophoresis with all-solid-state ion-selective electrodes. The sensitivity for these compounds is a function of their lipophilicity. The signal detected is generally greater for molecules with a larger organic part. The utility of ...
Lu Q - - 1998
PURPOSE: To better understand the nature of drug-excipient interactions we have studied the phase behavior of amorphous binary and ternary mixtures of citric acid, indomethacin and PVP, as model systems. METHODS: We have prepared amorphous mixtures by co-melting or coprecipitation from solvents, and have measured glass transition temperatures with differential ...
Vassileva M - - 1998
Spores of Aspergillus niger were encapsulated in agar, calcium alginate and k-carrageenan and further applied in citric acid production during six repeated batch cultivations. Rock phosphate (RP) at concentrations of 3 g l-1 and 7 g l-1 was supplemented to the culture medium to test encapsulated-fungus solubilizing capability. The highest ...
Radcliffe J S - - 1998
Crossbred weanling pigs (an equal number of barrows and gilts) with an average initial weight of 7.4 (Exp. 1) or 9.6 kg (Exp. 2) were used in two 4-wk experiments (Exp. 1, n = 96; Exp. 2, n = 96) to investigate the effects of added phytase or citric acid ...
Prohl C - - 1998
The operation of the citric acid cycle of Escherichia coli during nitrate respiration (anoxic conditions) was studied by measuring end products and enzyme activities. Excretion of products other than CO2, such as acetate or ethanol, was taken as an indication for a non-functional cycle. From glycerol, approximately 0.3 mol acetate ...
Roukas T - - 1998
The production of citric acid from carob pod extract by A. niger in surface fermentation was investigated. A maximum citric acid concentration (85.5 g/L), citric acid productivity (4.07 g/L/d), specific citric acid production rate (0.18 g/g/d), and specific sugar uptake rate (0.358 g/g/d) was achieved at an initial sugar concentration ...
Samelis J - - 1998
In an attempt to differentiate between Weissella viridescens, W. paramesenteroides, W. hellenica and some atypical arginine-negative Weissella isolates from meats, their cellular fatty acid composition was determined by a rapid GC method. Results showed that W. viridescens synthesized eicosenoic (n-C20:1) acid, while the other two species did not. Meanwhile, unlike ...
Adesunloye T A - - 1998
Gelatin capsule crosslinking is a well-known phenomenon that results in reduced dissolution of capsule products with the passage of time and/or under accelerated stability conditions. These studies describe one means of preventing capsule crosslinking by incorporating glycine and citric acid into a triamterene/hydrochlorothiazide 37.5/25 mg capsule formulation (triam/HCTZ). Triam/HCTZ without ...
Kock J L - - 1998
Dipodascopsis uninucleata has been recently shown to produce 3-hydroxy polyenoic fatty acids from several exogenous polyenoic fatty acids. In order to examine whether endogenous 3-hydroxy fatty acids (3-OH-FA) may be implicated in the developmental biology of this yeast, we mapped by immunofluorescence microscopy their occurrence in fixed cells with or ...
Odou P - - 1998
Midazolam is a benzodiazepine with short elimination half-life, used as induction or continuous agent for general anesthesia. At present, only injectable solution is available from French hospital pharmacies. The aim of the study is the development of 5 mg midazolam sublingual tablets to realize a short general anesthesia without intravenous ...
Hellström P M - - 1998
This study investigated the role of nitric oxide (NO) and adrenergic and dopaminergic mechanisms in reflex inhibition of the migrating myoelectric complex (MMC) after intraperitoneal administration of acid in rats. Acid instilled immediately after an activity front inhibited the migrating complex and prolonged the cycle length from 13.0 +/- 0.7 ...
Mato I - - 1998
To characterize honey types, a citric acid determination may be useful. A citric acid determination on honey was carried out with previous polyvinylpolypyrrolidone (PVPP) clarification followed by the Boehringer-Mannheim GmbH enzymatic test. The sample solution was prepared from 2 g of honey in 100 mL of Milli-Q water. A volume ...
Saso L - - 1998
The pharmacological treatment of calcium urinary stones, most of which are made of calcium oxalate (CaOx), is only prophylactic. The causes of nephrolithiasis are often unclear, and a number of patients were found to be deficient in physiological inhibitors, e.g. citrate, pyrophosphate, magnesium, and specific proteins. The identification and characterization ...
Kalapos M P - - 1998
The evolution can be divided into three stages: chemical, prebiological and biological evolution. Most of the problems emerge when the development of cellular organization, the so-called prebiological evolution, is investigated. Here the possible evolutionary roles for formaldehyde as well as for the methylglyoxalase pathway are proposed. The theory, on the ...
Ghosh P - - 1998
An ethyleneimine and UV irradiated mutant strain Aspergillus niger AB 1801 was explored for its aconitase activity, citric acid production and cell growth during citric acid fermentation. 10% sucrose and 0.25% urea served as the best carbon and nitrogen sources, respectively. Fe2+ stimulated aconitase activity and Co2+ (upto 5 micrograms/mL) ...
Aderiye B I - - 1998
The toxic effect of citric and succinic acids on the germination of the pycnidiospores ofBotryodiplodia theobromae, mycelial growth and the killing rate of theB. theobromae spores was investigated. The percentage inhibition of germination of viable fungal spores by 0.01% succinic or citric acid ranged between 51.6 and 58.1%, respectively.B. theobromae ...
Dress W - - 1997
Sarracenia purpurea L. (northern pitcher plant) is an insectivorous plant with extrafloral nectar that attracts insects to a water-filled pitfall trap. We identified and quantified the amino acids in extrafloral nectar produced by pitchers of S. purpurea. Nectar samples were collected from 32 pitchers using a wick-sampling technique. Samples were ...
Serkova N - - 1997
The toxic effect of the macrolide immunosuppressant sirolimus on cell metabolism of primary astrocytes was studied by multinuclear NMR spectroscopy of viable cells and perchloric acid (PCA) extracts and compared to the effects of the immunosuppressant cyclosporine. The addition of 5 mg/L sirolimus (5.5 mumol/L) induced swelling of primary astrocytes ...
Dieuaide-Noubhani M. - - 1997
Excised maize (Zea mays L.) root tips were used to study the early metabolic effects of glucose (Glc) starvation. Root tips were prelabeled with [1-13C]Glc so that carbohydrates and metabolic intermediates were close to steady-state labeling, but lipids and proteins were scarcely labeled. They were then incubated in a sugar-deprived ...
Fang D Q - - 1997
Fruit juice pH, titratable acidity, or citric acid content was measured in 6 populations derived from an acidless pummelo (pummelo 2240) (Citrus maxima (Burm.) Merrill). The acidless trait in pummelo 2240 is controlled by a single recessive gene called acitric. Using bulked segregant analysis, three RAPD markers were identified as ...
Pal S - - 1997
Azotobacter chroococcum MAL-201, when grown under nitrogen-free conditions with excess glucose, accumulated poly-beta-hydroxybutyric acid amounting to 75% of cell dry weight at the late exponential phase. This led to induction of encystment, which increased steadily with concomitant intracellular degradation of the polymer. Increase in encystment and PHB production were parallel ...
Lu Q - - 1997
To better understand the properties of citric acid when used in solid dosage forms as an acid-base buffer, we initiated a study of its properties in the amorphous state. Such a state often arises during processes such as lyophilization and wet granulation. In view of inconsistencies in the literature concerning ...
Barden T J - - 1997
A procedure in which anionic analytes, trapped on ion exchange resin, are simultaneously methylated and released using methyl iodide in either supercritical carbon dioxide or acetonitrile has been extended to polyfunctional organic acids. The combined SFE methylation of fruit juice acids trapped onto ion exchange resin proceeds in good yield ...
Stevens J C - - 1997
Detection thresholds for sodium chloride were compared in aqueous solution, in mixture with a sucrose masker, in mixture with a citric acid masker, and in mixture with both of these maskers together. Separately the two maskers raised the threshold of sodium chloride by three to four times, and together by ...
Giza B K - - 1997
Aversive conditioning has an impact on the neural signal for the gustatory conditioned stimulus (CS). Here, we determined whether the code is also affected by preference conditioning. We paired the taste of MgCl2 (CS+) with intragastric nutrients in some rats (MG), and citric acid (CS+) with nutrients in others (CI). ...
Law M F - - 1997
Different classes of excipients with potential for use in the design of novel pelletized formulations manufactured by extrusion-spheronization were examined using factorial experiments. Among the various silicates examined in a model mix with microcrystalline cellulose and lactose wetted with water, kaolin, talc and Veegum F provided improved plasticity for the ...
Barry P W - - 1997
1. Travellers to high altitude often complain of paroxysmal cough, which has not been previously investigated. We recorded overnight cough frequency and cough-receptor sensitivity to inhaled citric acid in a group of climbers travelling to 5300 m or higher. 2. Cough frequency, monitored in ten subjects, increased from a median ...
Pines O - - 1997
Saccharomyces cerevisiae accumulates L-malic acid through a cytosolic pathway starting from pyruvic acid and involving the enzymes pyruvate carboxylase and malate dehydrogenase. In the present study, the role of malate dehydrogenase in the cytosolic pathway was studied. Overexpression of cytosolic malate dehydrogenase (MDH2) under either the strong inducible GAL10 or ...
Bernstein E F - - 1997
BACKGROUND: Recently, there has been an exponential increase in the use of alpha-hydroxy acids in dermatologic practice. Their inclusion in a myriad of cosmetic preparations underscores their popularity. Among the clinical effects of alpha-hydroxy acids are their ability to prevent the atropy resulting from potent topical corticosteroids, improve the appearance ...
Fitzgerald B P - - 1997
This study investigated the hypothesis that for a subpopulation of horse mares continuation of estrous cycles during the nonbreeding season may be attributed to continued stimulatory glutamatergic activity on GnRH-secreting neurons. The gonadotropin response to the glutamatergic agonist N-methyl-DL-aspartic acid (NMA) was compared in cycling and anestrous mares during the ...
Gradisnik-Grapulin M - - 1997
A spontaneous rise in intracellular cyclic AMP (cAMP) levels was observed in the early stages of Aspergillus niger growth under conditions yielding large amounts of citric acid. The amount of cAMP formed was found to depend on the initial concentration of sucrose in the medium. Under higher-sucrose conditions, the cAMP ...
Netik A - - 1997
The uptake as well as the export of citric acid by Aspergillus niger occur by active, deltapH-driven, H(+)-symport dependent systems. They are inhibited by nonmetabolizable tricarboxylic acid analogues and phthalic acid, and by several other mono-, di- and tribasic organic acids. However, citrate export could only be demonstrated in a ...
Dabrosin C - - 1997
1. Previously it has been impossible to perform studies of human breast tissue in vivo. In this study, we investigated whether the microdialysis technique is applicable in human breast tissue and whether the concentrations of amino acids, lactate and pyruvate change during the menstrual cycle. 2. Microdialysis was performed twice ...
Riedel K - - 1997
The yeast Arxula adeninivorans LS3 is a suitable organism for use as part of a microbial sensor. In combination with an amperometric oxygen electrode the sensor offered a possibility for the physiological characterization of this yeast. About 300-400 measurements could be carried out with a single Arxula sensor. The microbial ...
Sheets R W - - 1997
Dinnerware decorated with overglaze designs can release toxic metals into food substances in amounts high enough to constitute health hazards. When dishes made in the US before 1970 were filled with 4% acetic acid for 24 h, lead concentrations of up to 610 micrograms/ml and cadmium concentrations of up to ...
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