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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 ...
Tran-Dinh S - - 1997
We propose a simple mathematical model and a practical approach for evaluating the flux constant and the absolute value of flux in the citric acid cycle in perfused organs by 13C-NMR and 1H-NMR spectroscopy. We demonstrate that 13C-NMR glutamate spectra are independent of the relative sizes of the mitochondrial and ...
Renvert S - - 1997
The purpose of the present study was to compare an enzyme immunoassay with culture samples from untreated and non-surgically treated periodontal pockets and to assess the clinical and microbiological effects of citric acid irrigation as a supplement to scaling and root planing. The enzyme immunoassay used in this study is ...
el-Sayad M H - - 1997
Prevention of human fascioliasis could depend on clearing of the leafy salads from the metacercariae. The present work evaluated the role of some chemicals in detaching and killing this infective stage. It was observed that washing in running water for 10 minutes detached only 50% of the metacercariae. Citric acid ...
Birch M - - 1997
We examined fast atom bombardment mass spectra (FAB-MS) of 29 clinical isolates of Aspergillus, from five pathogenic species, for the presence of phthioic acid anions (m/z 395.6) when grown at 37 degrees C. Phthioic acid was detected in only one of 12 A. fumigatus, three of nine A. terreus and ...
Babay N - - 1997
The scanning electron microscope was used to evaluate the effects of ultrasonic irrigation before and after root conditioning. Six groups of five specimens each received saline irrigation; ultrasonic irrigation; saline irrigation followed by root conditioning with either citric acid or tetracycline hydrochloride; or ultrasonic irrigation followed by root conditioning with ...
Bartine H - - 1997
None of the four Aspergillus flavus isolates studied was able to grow on wet cinnamon (5 g cinnamon + 3.3 mL distilled water) at 25 degrees C over 30 days. Fungal growth was weak on the curcumin, black pepper, and white pepper; good, but lower than on rice control, on ...
Tran-Dinh S - - 1996
We propose, first, a practical method for studying the isotopic transformation of glutamate or any other metabolite isotopomers in the citric acid and the glyoxylate cycles; second, two mathematical models, one for evaluating the flux through the citric acid cycle and the other for evaluating the flux through the latter ...
Green B G - - 1996
Topical desensitization of the tongue was assessed during multiple bouts of exposure to capsaicin. In the first experiment subjects rated perceived irritation as 30 capsaicin stimuli (33 microM) were applied to the tongue tip in three blocks of 10, with 15 min breaks between blocks. Significant desensitization was measured at ...
Gqaleni N - - 1996
The combined effects of water activity (a(w)) and temperature on mycotoxin production by Penicilium commune (cyclopiazonic acid - CPA) and Aspergillus flavus (CPA and aflatoxins - AF) were studied on maize over a 14-day period using a statistical experimental design. Analysis of variance showed a highly significant interaction (P ≤ ...
Yang S S - - 1996
Several microbes were isolated from the contaminated fuel-oil in Taiwan and the microbial corrosion of aluminum alloy A356-T6 was tested by MIL-STD-810E test method. Penicillium sp. AM-F5 and Cladosporium resinac ATCC 22712 had significant adsorption and pitting on the surface of aluminum alloy, Pseudomonas acruginosa AM-B5 had weak adsorption and ...
Pines O - - 1996
Saccharomyces cerevisiae accumulates L-malic acid but not only minute amounts of fumaric acid. A 13C-nuclear magnetic resonance study following the label from glucose to L-malic acid indicates that the L-malic acid is synthesized from pyruvic acid via oxaloacetic acid. From this, and from previously published studies, we conclude that a ...
Bachmanov A A - - 1996
Mice of the 129/J (129) and C57BL/6ByJ (B6) strains and their reciprocal F1 and F2 hybrids were offered solutions of ethanol, sucrose, citric acid, quinine hydrochloride, and NaCl in two-bottle choice tests. Consistent with earlier work, the B6 mice drank more ethanol, sucrose, citric acid, and quinine hydrochloride solution and ...
Crump T B - - 1996
OBJECTIVES: To determine and compare osseous regeneration associated with three guided tissue regeneration membrane types (expanded polytetrafluoroethylene, dense polytetrafluoroethylene, and an absorbable polylactic acid/citric acid ester base) and removal forces required for expanded and dense polytetrafluoroethylene membranes. STUDY DESIGN: Bilateral osseous defects were created in 30 adult rat calvaria; one ...
Lesage-Meessen L - - 1996
A two-step bioconversion process of ferulic acid to vanillin was elaborated combining two filamentous fungi, Aspergillus niger and Pycnoporus cinnabarinus. In the first step, A. niger transformed ferulic acid to vanillic acid and in the second step vanillic acid was reduced to vanillin by P. cinnabarinus. Ferulic acid metabolism by ...
Meléndez-Hevia E - - 1996
The evolutionary origin of the Krebs citric acid cycle has been for a long time a model case in the understanding of the origin and evolution of metabolic pathways: How can the emergence of such a complex pathway be explained? A number of speculative studies have been carried out that ...
Atilla G - - 1996
The purpose of this investigation was to determine the surface morphology and mineral content of periodontally diseased cementum surfaces following root planing and conditioning with either citric acid, tetracycline HCL and minocycline HCL. Mineral contents of cementum surfaces were determined with an electron probe. All 3 demineralizing agents caused the ...
Tanabe S - - 1996
Based on the wheat glutenin IgE-binding epitope, Gln-Gln-Gln-Pro-Pro, a practical method is proposed for the production of hypoallergenic wheat flour. Bromelain was found effective for decomposing the epitope structure. In practice, soft flour was mixed with water dissolving bromelain and the mixture was incubated at 37 degrees C for 4 ...
Merle M - - 1996
A mathematical model of the citric acid cycle devoted to the analysis of 13C-NMR data was developed for determining the relative flux of molecules through the anaplerotic versus oxidative pathways and the relative pyruvate carboxylase versus pyruvate dehydrogenase activities. Different variants of the model were considered depending on the reversibility ...
Romano A H - - 1996
Current studies of hyperthermophilic archaea and bacteria, the phylogenetically deepest-rooted and slowest-evolving extant organisms known, are allowing new insights into the nature of presumably ancient metabolic pathways. The apparent common occurrence of modified non-phosphorylated Entner-Doudoroff (ED) pathways among saccharolytic archaea and the absence of the conventional Embden-Meyerhof-Parnas (EMP) mode of ...
Arisan-Atac I - - 1996
Accumulation of citric acid by Aspergillus niger depends on a high flux through glycolysis. We have investigated the possibility of control of this flux by trehalose 6-phosphate, an inhibitor of hexokinase of Saccharomyces cerevisiae and other eukaryotes (Blasquez et al., FEBS Lett. (1993) 329, 51-54). Hexokinase of A. niger was ...
Kimura R E - - 1996
In the presence of glutamine, glucose, and 3-hydroxybutyrate, glutamine is the preferred oxidative substrate in enterocytes of suckling and weaned rats. Our studies of changes in intestinal metabolism in the developing rat clearly indicate that the oxidation of substrates that enter the citric acid cycle in the form of acetyl-CoA ...
Misra D N - - 1996
The use of citric acid is efficacious and distinctive in the demineralization of dentinal root surfaces for periodontal regeneration and in the etching and conditioning of enamel or dentin for bonding restorative resins. To decipher the role of citric acid in these applications, it is important that one have a ...
Sheets R W - - 1996
When samples of pre-1950s U.S.-made ceramic dinnerware, purchased in antique shops and flea markets, were filled with 4% acetic acid or 0.5% citric acid and heated in a microwave oven for 2-5 min, lead was leached in amounts of up to 5 mg per dish. Concentrations of lead in the ...
el-Samragy Y A - - 1996
The effect of pH value, methanol, and salt concentration on the production of citric acid from cheese whey by two strains of Aspergillus niger, i.e. CAIM 111 and CAIM 167, was investigated. Lactose concentration, utilized lactose, citric acid concentration, conversion coefficient of lactose to citric acid, and mycelial dry weight ...
Bier F F - - 1996
The amplification cycle consisting of NADH independent oligosaccharide dehydrogenase (ODH) and laccase has been recently reported to be highly sensitive to several catecholamines and p-aminophenol. A competitive immunoassay for 2,4-dichlorophenoxyacetic acid has been developed by combining this amplification cycle with beta-galactosidase as enzyme label resulting in p-aminophenol as product. The ...
Selvig K A - - 1996
Effects of topical citric acid application on tissue maturation was studied in standardized periodontal defects in 6 beagle dogs. Following elevation of facial mucoperiosteal flaps, fenestration defects, 3 mm in diameter, were made through the cortical bone and recessed 0.5 mm into the dentin of maxillary canines. 1 defect in ...
Khaskhali M H - - 1996
A simple method for the simultaneous determination of oxalic and citric acids had been developed using reversed-phase HPLC. An aqueous solution containing potassium dihydrogen phosphate (0.25%) and tetrabutylammonium hydrogen sulphate (2.5 mmol) at pH 2.0 was used as mobile phase. Under these conditions both the components were well resolved and ...
Suganuma T - - 1996
An acid-stable alpha-amylase (AA) was purified from an acidic extract of citric acid-koji (A. usamii var.). The N-terminal sequence of the first 20 amino acids of the enzyme was identical with that of AA from A. niger, but the two enzymes differed in molecular weight. HPLC analysis for identifying the ...
Yamaguchi M - - 1996
The purpose of this study was to investigate various properties of citric acid and EDTA solution as decalcifying and cleansing agents in root canal irrigation, and antibacterial effects of citric acid and EDTA solution. Powdered dentin-resin mixtures were used for evaluating the decalcifying effect of citric acid and EDTA solution. ...
Featherstone R L - - 1996
It has been suggested that bradykinin may play a role in stimulating cough in at least one pathological condition in humans. We have employed an animal model to investigate the possible role of this peptide in irritant-induced cough. The kinin antagonist Hoe 140 and codeine both produced dose-related inhibition of ...
Bashir E - - 1996
Citric acid contained in beverages and foods is one of the main causes of enamel erosion. It was hypothesized that the clearance of citric acid from saliva would influence the degree of salivary saturation with respect to hydroxyapatite (OHAp). Ten subjects rinsed with 2% citric acid, pH 2.1, for 5s. ...
Ashour S A - - 1996
The pattern and the extent of formation of proteases and secretion varied with the fungus, age and/or the nature of the co-supplement. Addition of yeast extract induced the best yield of proteases from both Aspergillus niger and A. terreus. Proteases from A. niger were highly induced by glutamic acid, alanine ...
Ono Y - - 1996
We have measured continuously the production of mass 45 CO2(13C16O2) from 13C-labeled pyruvate in a guinea pig liver mitochondrial suspension and simultaneously the O2 consumption at 37 degrees C and pH 7.4. The reactions took place in a closed 3-ml volume, stirred, thermoregulated chamber separated from the ion source of ...
Thomas C J - - 1995
Astringency, astringent subqualities (drying, roughing and puckering) and sourness were compared among six acids: hydrochloric, lactic, citric, acetic, fumaric and malic acids. The attribute profiles of organic acids were similar to each other but different from hydrochloric acid, the only inorganic acid, which was the most astringent and the least ...
Sumegi B - - 1995
The oxidation of [3-13C]pyruvate and [3-13C]propionate was studied in vivo in infused rats. The infused [3-13C]pyruvate was quickly converted to [3-13C]lactate in the blood, and the [3-13C]lactate formed was well metabolized in both normoxic and ischaemic hearts. Large differences (200-600%) in the 13C enrichment of alanine (C-3) and acetyl-CoA (C-2) ...
Schrickx J M - - 1995
Wild-type Aspergillus niger N402 and glucoamylase++ overproducing transformant A. niger N402[pAB6-10]B1 have grown in maltodextrin- and xylose-limited recycling culture at pH 4.5 on mineral medium. The only products formed were organic acids and proteins, among which glucoamylase. The production of organic acids by the fungus has been analyzed qualitatively and ...
Higashi T - - 1995
The surface characteristics of periodontally diseased human teeth after two treatments were compared both before and after partial demineralization with citric acid. Thirteen teeth were obtained from patients with advanced periodontal disease. Three teeth were selected for control groups and 10 were used for experimental groups. All diseased root surfaces ...
Maden B E - - 1995
In recent years, several alternatives to the classical prebiotic-soup model for the origin of life have been proposed. Among these, the theory of Wächtershäuser proposes that an archaic version of the autotrophic reductive citric acid cycle, driven by pyrite formation and contained on the resulting pyrite surface, was the earliest ...
Ivanov A G - - 1995
The exogenous application of abscisic acid (ABA) to barely seedlings resulted in partial protection of the PSII photochemistry against photoinhibition at low temperature, the effect being most pronounced at 10(-5) M ABA. This was accompanied by higher photochemical quenching (qP) in ABA-treated leaves. A considerable increase (122%) in the amount ...
MacDonald M J - - 1995
Previous studies indicated that in pancreatic islets the amount of glucose-derived pyruvate that enters mitochondrial metabolism via carboxylation is approximately equal to that entering via decarboxylation and that both carboxylation and decarboxylation are correlated with capacitation of glucose metabolism and insulin release. The relatively high rate of carboxylation is consistent ...
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