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PubMed1980

Inhibition of the plasma cholinesterase variants by pancuronium bromide and some of its analogues.

Pancuronium bromide, a 3,17-diacetoxy-5 alpha-androstane, and three of its analogues, the 17-desoxy, the 3,17-dibutyryloxy and the 16-N-monoquaternary ammonium derivatives have been used as inhibitors of the usual and atypical plasma cholinesterase variants. In all cases the usual enzyme is more sensitive to inhibition by the substituted steroids than the dibucaine resistant enzyme. The relative affinities of the bis-quaternary ammonium compounds for either enzyme is in the order dibutyryloxy derivative > 17-desoxy derivative greater than or equal to pancuronium bromide. The monoquaternary compound has the least affinity of all the inhibitors for the usual enzyme but the greater affinity for the atypical enzyme. These observations show that the bis-quaternary compounds are very powerful differentiators of the variants. The monoquaternary derivative shows less differential inhibition, but provides additional evidence that the usual and dibucaine resistant variants differ in structure at or near their esteratic active site.

Cholinesterase Inhibitors↗
PubMed1995

On-line coupling of micellar electrokinetic chromatography to electrospray mass spectrometry.

The possibility of selectivity enhancement in capillary electrophoresis-mass spectrometry (CE-MS) by hyphenating micellar electrokinetic chromatography (MEKC) and electrospray mass spectrometry (MS) is described for two quaternary ammonium compounds. Direct coupling of MEKC to MS is hazardous because of the contamination of the ion source due to presence of an excess of micelle forming agent in the MEKC buffer. Therefore, a coupled-capillary setup with the possibilities of voltage switching and buffer renewal has been designed. Such a system allows on-line heartcutting of the zones of interest in the MEKC capillary with subsequent transfer via a second capillary to the mass spectrometer.

Buffers↗
PubMed1989

An in vitro study of the antibacterial and antifungal properties of an irreversible hydrocolloid impression material impregnated with disinfectant.

The difficulties associated with the disinfection of alginate (irreversible hydrocolloid) materials have resulted in the development of an irreversible hydrocolloid impression material impregnated with an antimicrobial compound, didecyldimethyl ammonium chloride. This investigation assessed the antibacterial and antifungal properties in vitro of this innovative irreversible hydrocolloid material by using the agar well technique. The microorganisms used were Pseudomonas aeruginosa, Streptococcus mutans, Streptococcus sanguis, Lactobacillus odontolyticus rodriguez, Actinomyces odontolyticus, mixed salivary organisms, and Candida albicans. The results showed an absence of activity against Pseudomonas aeruginosa. Varying degrees of antibacterial activity were exhibited against the other microorganisms. It is concluded that it is not know whether the limited antibacterial and antifungal effect demonstrated in this study is sufficient to prevent bacterial and fungal colonization of the impression surface in the mouth during clinical practice.

Actinomyces↗
PubMedDate not supplied

Pharmacological actions of levallorphan allyl bromide (CM 32191), a new peripheral narcotic antagonist.

A dissociation of the effects of the newly synthesized quaternary ammonium narcotic antagonist, levallorphan allyl bromide (CM 32191) on morphine-induced analgesia and constipation in the mouse is reported. CM 32191 behaved as a pure morphine antagonist on the "in vitro" preparation of longitudinal muscle of guinea-pig ileum and antagonized dose-dependently the peripherally mediated morphine constipation (ID50:15.6 mg/kg) without significantly affecting morphine analgesia (ID50: greater than 80 mg/kg). Its peripheral selectivity was greater than that of another quaternary ammonium compound, N-methyl naloxone. It is proposed as a useful pharmacological tool to differentiate the peripherally mediated from the centrally mediated effects of opioids.

Animals↗
PubMed1986

Comparative study of the configuration and the cleanliness level of root canals prepared with the aid of sodium hypochlorite and bis-dequalinium-acetate solutions.

Bis-dequalinium acetate (BDA), a quaternary ammonium compound, was introduced as a bactericidal and chemotherapeutic agent for endodontic use. This study was undertaken to compare the efficacy of this compound to 5.25% sodium hypochlorite in the cleansing and shaping of root canals. One hundred twenty freshly extracted teeth were divided into three groups. Each group was treated with the aid of the test material; saline solution was used as a control. After completion of the endodontic preparation, a silicone imprint of the canals was performed and the teeth were decalcified. The imprints were examined three-dimensionally to determine the amount of debris and canal configuration due to defective preparation and anatomic variation. No significant difference could be observed between the tested materials with respect to cleanliness and the shape of the canals. At the apical third, however, the BDA-treated canals showed more favorable results with respect to cleanliness. On the basis of the present and previous findings, it was concluded that BDA might be a favorable replacement for sodium hypochlorite as an irrigation solution.

Dental Pulp Cavity↗
PubMedDate not supplied

Aminosidine ointments for the treatment of experimental cutaneous leishmaniasis.

A 15% aminosidine sulphate (AS)/10% urea/white soft paraffin (WSP) ointment cured all Leishmania major lesions on Balb/C mice following topical application for 10 d. Some relapses were observed 10 weeks after treatment. AS alone in WSP ointment was also highly effective. The ointment containing urea was non-irritant to mice, whereas ointments containing quaternary ammonium compounds were irritant. The 15% AS/10% urea/WSP ointment was not effective in the treatment of L. mexicana or L. panamensis lesions on Balb/C mice, no cure being observed.

Animals↗
PubMed1979

Overview of some aspects of occurrence, formation and analysis of nitrosamines.

This review principally addresses a number of aspects of the occurrence and formation of the nitrosamines, highlighting principal areas of potential concern ranging from the spectrum of nitrosatable moieties found in the environment (e.g., secondary and tertiary amines, quaternary ammonium compounds, ureas, carbamates and guanidines), specific examples of nitrosamines found in food, alcoholic beverages, feed (and their significance for carcinogenesis bioassays), air and water. The factors influencing in vitro and in vivo nitrosation and the evidence for the latter in man are also discussed. Additionally, germane areas of the analysis of nitrosamines are reviewed with a focus on the major areas of concern and requirements of extreme sensitivity and selectivity in addition to the problems of artifacts in the analytical procedures.

Air Pollution↗
PubMedDate not supplied

Ion conductances in the microvillous and basal membrane vesicles isolated from human placental syncytiotrophoblast.

Experiments were performed to characterize the ionic conductances in microvillous and basal membranes from human placenta. Microvillous and basal membranes were prepared from term placental tissue by homogenization, magnesium precipitation, differential and sucrose density gradient centrifugation. The relative permeabilities of sodium, potassium and chloride were measured using the bi-ionic potential technique which employs a fluorescent probe [diS-C3-(5)] which partitions into membranes in a potential-dependent manner. The permeabilities of sodium and chloride relative to potassium were determined by measuring their effects on a known membrane potential produced by a potassium gradient. In microvillous membranes PNa/PK = 0.25 and PClPK = 0.19 while in basal membranes, PNa/PK = 1.31 and PCl/PK = 0.03. Measurements of chloride permeability relative to sodium confirmed these results. The cation conductances were inhibited by quaternary ammonium compounds. Addition of tetramethylammonium altered the relative permeabilities in a pattern suggesting a block of potassium conductance while tetraethylammonium appeared to block both sodium and potassium conductances.

Basement Membrane↗
PubMed1992

Immunostimulants added to injected Aeromonas salmonicida bacterin enhance the defense mechanisms and protection in rainbow trout (Oncorhynchus mykiss).

Immunostimulants were given to rainbow trout for assaying effects on modulating non-specific defense mechanisms, specific immune response, and protection levels against pathogen challenge with Aeromonas salmonicida. Three drugs, levamisole (an approved veterinary drug in the USA), a quaternary ammonium compound (QAC), and a short-chain polypeptide (ISK) were found to affect the non-specific defense mechanism activities, which were measured by changes in circulatory neutrophil and phagocytic activity levels, and the specific immune response factors, which were measured by numbers of plaque-forming cells, and circulatory antibody levels. When given alone, the immunostimulants elevated the non-specific factors. When injected in combination with an A. salmonicida O-antigen bacterin, the non-specific factors were further elevated, and the specific response was raised over samples taken from fish given the bacterin without the immunostimulants. Challenge tests with the virulent pathogen, A. salmonicida, showed a 5-6 day delay in the onset of mortalities in the fish given the immunostimulants alone, and a 12-14 day delay when immunostimulants given were combined with the bacterin. In the groups given the QAC or ISK with the bacterin, there was a 20% and 40% survival rate, respectively.

Adjuvants, Immunologic↗
PubMed1986

Susceptibility of porin- and lipopolysaccharide-deficient strains of Escherichia coli to some antiseptics and disinfectants.

The sensitivities of some outer membrane protein (Omp) and/or lipopolysaccharide (LPS)-defective mutants of Escherichia coli to chlorhexidine and some quaternary ammonium compounds (QACs) were examined. Wild-type strains, with no defect in Omp or LPS were the most resistant to QACs, whereas LPS-deficient strains were the most sensitive. As expected, QAC resistance could not be related to the presence or absence of any specific porin(s). Chlorhexidine was highly active against all strains, inhibitory concentrations lying within the narrow range of 1 and 2 mg l-1.

Anti-Bacterial Agents↗
PubMed1994

Feasibility of a combined carrier test for disinfectants: studies with a mixture of five types of microorganisms.

BACKGROUND: There is mounting concern regarding the efficacy of many germicides on the market because officially recognized germicidal tests for various classes of microorganisms vary widely and often lack reproducibility and proper quantitation. We report here a carrier method for simultaneously and quantitatively assessing the efficacy of liquid chemical germicides against a mixture of microorganisms of varying degrees of resistance. METHODS: In the test, each small glass cup (10 mm wide x 14 mm long) was contaminated with 10 microliters of a standardized mixture of Staphylococcus aureus, Mycobacterium bovis bacille Calmette-Guérin, Trichophyton mentagrophytes spores, Sabin poliovirus type 1, and Bacillus stearothermophilus spores in 5% fetal bovine serum. The inoculum was dried for 60 minutes under ambient conditions and covered with 60 microliters of the disinfectant under test or a balanced salt solution control for the desired contact time. The carrier was then placed in 2940 microliters of an eluent and the eluates assayed separately for the five microorganisms. Tap water was used to dilute the test product as needed. RESULTS: Of the 11 products tested, 2% alkaline glutaraldehyde, 0.6% sodium hypochlorite (about 5000 ppm free chlorine), and a 0.4% quarternary ammonium compound containing 23% hydrochloric acid were effective against all five challenge organisms. A hard-surface spray containing 0.1% o-phenylphenol with 79% ethanol was effective against all but bacterial spores; 70% (volume/volume) ethanol alone and povidone-iodine (1% available iodine) were effective against S. aureus, the mycobacterium, and the fungus; a 3% solution of peroxygen compounds was effective only against S. aureus and the poliovirus; 1.5% chlorhexidine gluconate, 0.06% quaternary ammonia compound, and 0.03% o-phenylphenol + 0.03% p-tertiary amylphenol could inactivate nothing but S. aureus; and 3% hydrogen peroxide was ineffective in all tests. CONCLUSIONS: This method shows promise for use with various classes of microorganisms, individually or as mixtures. Its application should enable the classification of germicides according to spectrum of activity.

Disinfectants↗
PubMed1984

Electron microscopical autoradiography of [3H]choline fixed by phosphomolybdic acid in the motor nerve terminal.

The 'ionic fixation' of soluble quaternary ammonium compounds such as choline and acetylcholine by phosphomolybdic acid was used to fix [3H]choline taken up in the frog motor nerve terminal. The rapid 'ionic fixation' allowed autoradiography of [3H]choline directly at the electron microscopic level without considerable diffusion artifacts. Most of the radioactivity was localized in the motor nerve terminal and to a lesser degree, in Schwann cell processes and muscle fibers. These findings are in favor of our previous hypothesis of acetylcholine fixation by molybdic or tungstic heteropolyanions in the motor nerve terminal.

Acetylcholine↗
PubMed1990

Action of pinaverium bromide, a calcium-antagonist, on gastrointestinal motility disorders.

1. The evidence reviewed here indicates that pinaverium bromide (Dicetel) relaxes gastrointestinal (GI) structures primarily by inhibiting Ca2+ influx through potential-dependent channels of surface membranes of smooth muscle cells. 2. The in vivo selectivity of pinaverium bromide for the GI tract appears to be due mainly to its pharmacokinetic properties. Because of its low absorption (typical for quaternary ammonium compounds) and marked hepatobiliary excretion, most of the orally-administered dose of pinaverium bromide remains in the GI tract. 3. Orally-administered pinaverium bromide does not elicit adverse cardiovascular side-effects at doses that effectively relieve GI spasm, pain, transit disturbances and other symptoms related to motility disorders. 4. Pinaverium bromide is the only Ca2(+)-antagonist with known therapeutic efficacy in the treatment of irritable bowel syndrome and certain other functional intestinal disorders.

Animals↗
PubMed1992

A pharmacological profile of glycopyrrolate: interactions at the muscarinic acetylcholine receptor.

1. Glycopyrrolate, a synthetic quaternary ammonium compound had biphasic effects on the contraction of guinea-pig atrium. At concentrations between 0.4 and 20 microM, glycopyrrolate induced a small but consistent increase in the contraction force. 2. Further increase in the concentration of glycopyrrolate produced a concentration-dependent reduction in the force of contraction with a EC50 of 0.24 mM. 3. This negative inotropic effect was opposed by a Ca2+ channel agonist, Bay K 8644. Glycopyrrolate also antagonized potently the depressant effects of carbachol and acetylcholine in guinea-pig atrium. 4. Schild analysis showed a pA2 value of 8.16 against carbachol and 8.39 against acetylcholine. These similar pA2 values suggested that both compounds may have a common interacting site. The interactions however cannot be explained by a simple competition model as the slopes of the Schild plots were larger than unity. 5. The mutual competition between glycopyrrolate and quinuclidinyl benzilate (QNB), gallamine or methoctramine indicated that glycopyrrolate could have multiple action sites in the atrium. Interaction at an allosteric site was implicated. 6. Radioligand binding studies showed that glycopyrrolate displaced pirenzepine (PZ) and AF-DX 384 from their binding to the M1 and M2 muscarinic receptors in guinea-pig brain membranes respectively. 7. The respective binding constants (Kis) were 0.60 and 0.03 nM. The Hill coefficient value (nH) for glycopyrrolate against [3H] PZ was larger than unity, suggesting positive cooperativity at the receptor complex. In contrast, the nH of the agonist [3H] AF-DX 384 was not different from unity, indicating a simple competitive inhibition. 8. Our results confirm the antimuscarinic properties of glycopyrrolate.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1992

Ammonium ion increases the tone of rat portal vein.

1. The effect of ammonium ion on vascular tone was investigated using the portal vein isolated from rat. 2. Ammonium chloride at 10-90 mM induced a contractile response. 3. Spontaneous twitch contraction of portal strips was augmented by ammonium chloride at 10-60 mM. 4. Ammonium chloride-induced contraction was abolished in calcium-free solution or in the presence of 1 microM nifedipine. 5. Methylamine (60 mM) also induced a contractile response and augmented the spontaneous twitch contraction in rat portal vein. 6. After withdrawal of ammonium chloride or methylamine from the organ bath solution, the spontaneous twitch contraction was strongly inhibited. 7. These results suggest that ammonium compounds increase vascular tone by causing influx of extracellular calcium through the voltage-dependent calcium channel and intracellular alkalinization is involved in this process.

Ammonia↗
PubMed1988

Quantitation of pancuronium, 3-desacetylpancuronium, vecuronium, 3-desacetylvecuronium, pipecuronium and 3-desacetylpipecuronium in biological fluids by capillary gas chromatography using nitrogen-sensitive detection.

A sensitive and specific capillary gas chromatographic (GC) assay was developed for the quantitation of the quaternary ammonium steroidal neuromuscular blocking drugs pancuronium (PANC), vecuronium (VEC) and pipecuronium (PIP), as well as the metabolites 3-desacetylpancuronium (3-desPANC) and 3-desacetylvecuronium (3-des VEC) in plasma, bile and urine; the putative metabolite 3-desacetylpipecuronium (3-des PIP) was extracted and quantitated only in urine. The procedure employed a single dichloromethane extraction of the iodide ion-pairs of the monoquaternary or bisquaternary ammonium compounds (including internal and external standards) from acidified, ether-washed biological fluid followed by the formation of stable O-tert.-butyldimethylsilyl derivatives at the 3-hydroxy steroidal position of the metabolites. An automated capillary GC system fitted with a nitrogen-sensitive detector and an integrator was then used to analyze and quantitate both parent compounds and their derivatized metabolites. Optimal extraction, derivatization and GC conditions, as well as short-term stability and recoveries of these drugs and metabolites in plasma, are reported. Electron ionization mass spectrometry combined with GC was used to confirm the identities of compounds eluted from the column. The assay demonstrated a 10(3)-fold linear range up to 5000 ng/ml for PANC, VEC, 3-des VEC and PIP, and lower limits of detection with adequate precision of 2 ng/ml for PANC, VEC and PIP, and 4 ng/ml for 3-des VEC; 3-des PANC was linear from 8 to 500 ng/ml while 3-des PIP was linear from 25 to 1000 ng/ml. The precision (coefficient of variation) of the calibration curves for underivatized drugs and their derivatized metabolites over the linear ranges was 2-20% and the reproducibility of the assay over a range of clinical concentrations of these drugs found in human plasma was 5-16% for PANC, 2-4% for VEC and 6-11% for PIP. No interferences were detected in the assay of plasma samples from 106 surgical patients.

Androstane-3,17-diol↗
PubMed1986

Determination of succinyldicholine in different tissue samples from guinea pigs after injection of a single intravenous dose.

The distribution and postmortem stability of succinyldicholine in different tissues and urine from guinea-pigs has been studied. Succinyldicholine was extracted from tissue homogenates and urine samples from animals sacrificed by intravenous injections of succinyldicholine hydrochloride (40 mg/kg). The bis-quaternary ammonium compound was demethylated and the tertiary amine was analysed by gas chromatography/mass spectrometry. The concentrations found in muscle, kidney and urine were often low; in muscle below 5 pmol/g, in kidney from 5 to 1500 pmol/g and in urine from 5 to 650 pmol/ml. The eye proved to be the best tissue sample, with a rather high and constant concentration (280 +/- 36 pmol/g) of succinyldicholine. The postmortem stability was studied by storing the bodies at 4 degrees C. After 6 days storage the drug concentrations in the eyes started to decline. Four weeks after death it was not possible to detect any succinyldicholine in this tissue.

Animals↗
PubMed1992

Fundamental studies in reversed-phase liquid-solid extraction of basic drugs; III: Sample matrix effects.

Using a set of 13 basic solutes (including a quarternary ammonium compound) with controlled pKa, log P and plasma protein binding, the factors which influence the extraction of these compounds from plasma by reversed-phase liquid-solid extraction have been studied. Direct analysis of plasma, avoiding deproteination, etc., is possible providing the sample is applied to the cartridge under the appropriate conditions. These conditions are dictated by the degree of plasma protein binding and are controlled and predicted from the lipophilicity of the compound. Plasma samples containing lipophilic compounds (log D(pH 7.4) > 2.03) require acidification and samples containing more polar compounds (log D(pH 7.4) < 0.9) should be applied untreated. Failure to use the appropriate conditions can result in significant losses from the cartridge on application or washing. In the intermediate lipophilicity range the optimal application conditions cannot be predicted. The effect of various aqueous-organic wash solvents have been investigated, and it was found that the cationic but not the proteinaceous components of plasma also affect the extraction process. This phenomenon which is probably due to an attenuation of the secondary cation exchange mechanism, results in more facile elution than when compounds are applied in water.

Atenolol↗