Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0010200 (cough)
 23,843 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine the short-term and long-term effects of organic solvents on the respiratory tract, 26 male floorlayers exposed to organic solvents were compared with 36 persons unexposed to such substances. The investigation primarily included a detailed history, determination of solvent concentration in the air inhaled by the workers, long-term ECG during the entire shift and lung-function test (vital capacity, forced expiratory volume in one second, flow volume curve) as well as non-specific bronchial inhalation challenge using a 3% acetylcholine aerosol before and after the shift. The floorlayers were primarily subjected to inhalative exposure to adhesives containing mixtures of toluene, petroleum hydrocarbons, ethyl acetate, methanol and acetone or one of these substances alone. This frequently resulted in short-term value limit excesses, especially in the MAK value (standardised threshold concentration in Germany) for toluene, which is a prime component of neoprene glue. Of the 26 floorlayers, 6 complained of breathlessness and coughing, whereas 13 suffered from nasal discharge and blockage--symptoms closely related to work. The smokers in this group showed a decline in lung function during the shift--especially in the forced expiratory volume in 1 s (FEV1)--as compared with the non-smokers in this group and the persons in the control group. This probably due to the combination of noxious substances. A strong correlation between occupational age and changes in lung function was observed: the occupationally youngest workers demonstrated the highest decrease in values during the course of the shift. There was no evidence of either obstructive or restrictive respiratory disorders or of marked deviation from the European Community for Coal and Steel (ECCS) references.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Alterations in lung function due to mixtures of organic solvents used in floor laying. 185 23

A simple, rapid and accurate method for the simultaneous determination of active ingredients in cough-cold mixtures using isocratic reversed-phase ion-pair high-performance liquid chromatography has been developed. It involves the use of an octadecylsilane column as the stationary phase with methanol, water, tetrahydrofuran, phosphoric acid mixtures as mobile phase including sodium dioctylsulphosuccinate as the ion-pair agent. The pH of the mobile phase was adjusted to 4.6 by means of phosphoric acid and ammonium hydroxide solutions. The proposed method involves the simple dilution of the samples with the mobile phase and the addition of metoclopramide hydrochloride as the internal standard. The active ingredients under investigation were chlorpheniramine, codeine, diphenhydramine, ephedrine, ethylmorphine, phenylephrine, phenylpropanolamine and pholcodine, which exist as various combinations in cough-cold mixtures. The optimum composition of the mobile phase and the optimum flow rate were determined and are reported. The method was applied to the determination of active ingredients in seven commercially available cough-cold mixtures.
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PMID:The simultaneous determination of active ingredients in cough-cold mixtures by isocratic reversed-phase ion-pair high-performance liquid chromatography. 257 52

The separation and simultaneous determination, by high-performance liquid chromatography, of acetaminophen (I), guaifenesin (II), pseudoephedrine hydrochloride (III), and pholcodine (IV), together with a series of parabens (methyl to butyl, V-VIII) in a cough mixture, has been demonstrated using a chemically bonded octadecylsilane stationary phase with a mobile phase of methanol-water-acetic acid (45:55:2) containing the ion-pairing agent octanesulfonic acid. Retention volumes for the active ingredients were 3.8 ml, 5.4 ml, 9.4 ml, and 15.6 ml for compounds I-IV, respectively. Corrected retention volumes for the parabens [5.4 ml for methyl (V), 9.6 ml for ethyl (VI), 18.5 ml for propyl (VII), and 37.9 ml for butyl (VIII)] showed an exponential relationship with chain length of the esterifying alcohols. Excipients did not interfere with the estimation of any of the compounds, hence pretreatment of the sample was unnecessary. Average recoveries of the active ingredients and of the parabens from laboratory prepared samples were essentially 100% of theoretical with standard deviations of 1.7, 0.3, 1.5, 0.3, 0.3, 3.3, 0.7, and 2.7% for I-VIII, respectively.
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PMID:Simultaneous determination of acetaminophen, guaifenesin, pseudoephedrine, pholcodine, and paraben preservatives in cough mixture by high-performance liquid chromatography. 683 61

Acetaminophen (I), guaifenesin (II), and dextromethorphan hydrobromide (III) were separated and quantitated simultaneously in cough syrup by high-pressure liquid chromatography. A chemically bonded octadecylsilane stationary phase was used with a mobile phase of 48% (v/v) aqueous methanol. The mobile phase pH was stabilized to 4.2 by adding formic acid--ammonium formate buffer (approximately 0.4%). The internal standard was o-dinitrobenzene. Retention volumes were 4 ml for I, 6 ml for II, 11 ml for the internal standard, and 20 ml for III. Inactive syrup components did not interfere, permitting direct diluted sample injection. Results on active ingredients were essentially 100% of the claim, with standard deviations of +/- 1.5, 1.2, and 2.1% for I, II, and III, respectively.
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PMID:Simultaneous high-pressure liquid chromatographic determination of acetaminophen, guaifenesin, and dextromethorphan hydrobromide in cough syrup. 735 28

Methyl and propyl parahydroxybenzoate (MPHB, PPHB), phenylephrine hydrochloride (PE) and chlorphenamine maleate (CPM) are often combined as ingredients in cough-syrups. Due to distinct chemical structures, pKa values among other chemical properties are different. This may result in a particular chromatographic behaviour on ion-pair reversed-phase liquid chromatographic (LC) systems. A face-centred central composite design was applied to study the impact of four LC mobile phase parameters and parameter interactions on the retention of these four compounds. The mobile phase parameters studied were the concentration of methanol as organic modifier, the concentration of sodium dioctylsulphosuccinate (SDSS) as counter-ion, the concentration of dimethyloctylamine (DMOA) as competitive base and the pH. By means of the proposed design, mathematical regression models and response surface plots were calculated, which could predict the compounds' retention times with good statistical reliability. Adequate combination of the most relevant of these mobile phase parameters enabled complete chromatographic separations within short times of analysis.
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PMID:Experimental design for the rapid selection of separation conditions for methyl and propyl parahydroxybenzoate, phenylephrine hydrochloride and chlorphenamine maleate by ion-pair liquid chromatography. 784 34

Monitoring by means of blood and urine analysis for methanol was successfully applied in 32 male workers who were exposed to methyl methacrylate (MMA) monomer at 6 ppm as a geometric mean and at 112 ppm as the maximum. Measurement of time-weighted average (TWA) intensity of the vapor exposure was successfully conducted with a diffusive sampler with activated carbon cloth as an adsorbent. Methanol concentrations in whole blood, serum, and urine samples were measured by headspace gas chromatography. The methanol concentrations in the three biological samples collected at the end of 8-h workshifts related linearly with the TWA MMA vapor concentrations, with correlation coefficients of 0.8-0.9. Quantitative evaluation of MMA in vapor and of methanol in urine suggests that only 1.5% of MMA inhaled will be excreted in urine as methanol. There were no significant clinical symptoms or abnormal hematological or serum biochemical findings at this exposure level, except that some workers complained throat irritation and frequent cough and sputa. The results indicate that biological monitoring by analysis for methanol is sensitive enough to detect MMA exposure at levels at which no serious health effects are to be expected.
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PMID:Biological monitoring and possible health effects in workers occupationally exposed to methyl methacrylate. 814 32

A simple, rapid and convenient chromatographic method, which permits the simultaneous determination of chlorpheniramine (CP) and maleate (MA), recently developed by the authors was applied to the analysis of chlorpheniramine maleate (CPM) in cough and cold drugs. In this method, a Capcell Pak C8 column and an isocratic mobile phase containing 15% methanol, 50 mM KH2PO4 and 5mM tetra-n-butylammonium phosphate as an ion-pair reagent were used. By using the mobile phase adjusted to pH 3.0 with orthophosphoric acid, fumaric acid, MA, CP, acetaminophen (paracetamol), caffeine, and m- and p-hydroxybenzoic acid as candidates for an internal standard were eluted separately within 17 min. Detection was carried out with UV detector at 215 nm. Under the same conditions, five other antihistamines analogous to CPM were also separated. The calibration graphs for CP and MA showed good linearity in the range of 0.5-10 nmol (0.195-3.9 micrograms) per 20 microliters injection, respectively. The proposed method was successfully applied to the simultaneous determination of CP and MA, i.e., CPM analysis, in commercial cough and cold drugs which pharmaceutical forms were tablet, granule and syrups.
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PMID:[Quantitative analysis of chlorpheniramine maleate in cough and cold drugs by ion-pair high-performance liquid chromatography for the simultaneous determination of chlorpheniramine and maleate]. 870 8

In a previous paper (J. O. De Beer, C. V. Vandenbroucke and D. L. Massart, J. Pharm. Biomed. Anal., 12, (1994) 1379-1396) liquid chromatographic (LC) retention modelling of the cough-syrup compounds methyl para-hydroxybenzoate (MPHB) and propyl para-hydroxybenzoate (PPHB), phenylephrine hydrochloride (PE) and chlorphenamine maleate (CPM) was studied using a face-centred central composite design. It is examined whether smaller half-fractional and full factorial designs with fewer experiments tend to reliably predict retention times of the latter compounds as well. Simplified regression modelling, however, neglecting more first-order and interactive effects and disregarding pure second-order effects, has to be set up. These smaller designs finally satisfy the prediction of the retention of MPHB, PPHB and PE also. Retention prediction of CPM is much less accurate. CPM has a pKa value of 4.0, which is encompassed by the examined mobile phase pH limits 3.0 and 5.0. Since the largest retention shifts occur near the pKa value, retention prediction in this area becomes more complex. CPM retention modelling from a full factorial design is useful if the mobile phase pH is fixed at 5.0 for methanol as well as for acetonitrile as organic modifers. The full factorial design, applied with acetonitrile as organic modifer, enables the selection of suitable LC parameter combinations for fast and complete separation of the four compounds in cough-syrup analysis.
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PMID:Half-fraction and full factorial designs versus central composite design for retention modelling in reversed-phase ion-pair liquid chromatography. 873 82

Liquid chromatographic methods were developed for the determination of bromhexine hydrochloride, methyl p-hydroxybenzoate and propyl p-hydroxybenzoate (method A) and dextromethorphan hydrobromide (method B) in cough-cold syrup formulations. Reversed-phase analytical columns (150 mm x 3.9 mm i.d.) were used with (A) C18 and (B) phenyl as stationary phases and mixtures of (A) acetonitrile and aqueous 15 mM triethylamine solution (43:57) and (B) methanol and aqueous 3% ammonium formate buffer solution (53:47) as mobile phases at a flow rate of 1.0 ml min-1. Both aqueous components were adjusted to pH 3.9. UV detection of analytes was at (A) 245 nm and (B) 278 nm. In both methods, the time required for an HPLC run giving good separations and recoveries was less than 8 min.
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PMID:Simultaneous determination of bromhexine hydrochloride and methyl and propyl p-hydroxybenzoate and determination of dextromethorphan hydrobromide in cough-cold syrup by high-performance liquid chromatography. 893 31

The methanol extract of Drymaria cordata Willd. was investigated for its effect on a cough model induced by sulfur dioxide gas in mice. It exhibited significant antitussive activity when compared with the control in a dose-dependent manner. The antitussive activity of the extract was comparable to that of codeine phosphate, a prototype antitussive agent. The D. cordata extract (100, 200, 400 mg/kg) showed 11.6%, 31.6% and 51.5% inhibition of cough with respect to the control group.
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PMID:Studies on antitussive activity of Drymaria cordata Willd. (Caryophyllaceae). 914 57


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