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At least 703 records · Page 39Linked to original sources
PubMed1989

Effect of N,N'-bis(alkyldimethyl)-alpha, omega-alkanediammonium dibromides on bacteria of the genus Clostridium.

Antibacterial effect of 17 ammonium compounds of the type of N,N'-bis(alkyldimethyl)-alpha, omega-alkanediammonium dibromides was tested on anaerobically sporulating bacteria of the genus Clostridium. A sizable antibacterial activity was displayed by five N,N'-bis(alkyldimethyl)-1,6-hexanediammonium dibromides and by four N,N'-bis(decyldimethyl)-alpha, omega-alkanediammonium dibromides. These compounds exhibited activity higher than, or comparable with, that of the reference standards Ajatin and Septonex. The maximum antibacterial activity was found in compounds whose alkyl chain contained 9-12 carbon atoms. Compounds with a lower number of carbon atoms in the chain (less than 8) exhibited a low activity.

Benzalkonium Compounds↗
PubMed1986

Occupational dermatitis to 2,3-epoxypropyl trimethyl ammonium chloride.

4 workers developed hand dermatitis in an automated starch modification process plant. 2,3-epoxypropyl trimethyl ammonium chloride (EPTMAC), a quaternary ammonium compound used as a cationizing chemical, produced allergic reactions in all 4 patients. They had only been in contact with EPTMAC for a short time before developing dermatitis, which indicates that EPTMAC is a strong sensitizer. Immunohistochemistry and electron microscopy showed the features of an allergic patch test. An industrial hygiene project was initiated at the factory to prevent new cases. It revealed many risks of skin contact with the process chemicals. Thus an automated process does not guarantee protection.

Allergens↗
PubMed1993

Resistance to lipophilic cationic compounds in multidrug resistant leukemia cells.

Previously we have shown that multidrug resistant cells are cross-resistant to certain permanently charged cationic lipophilic compounds. In the present study we extend these observations to additional cationic lipophilic compounds with unrelated chemical structures. Study of the growth inhibitory activity of series of triphenylalkyl-phosphonium and alkyl-ammonium compounds revealed that cross-resistance to these compounds in multidrug resistant P-388 murine leukemia cells, was related to the presence of cationic charge but not to the molecular size/degree of lipophilicity.

Animals↗
PubMed2006

Study of overload for basic compounds in reversed-phase high performance liquid chromatography as a function of mobile phase pH.

The retention and overloading properties for eight basic solutes and two quaternary ammonium compounds were studied over the pH range 2.7-10.0 using phosphate and carbonate buffers. At low pH, a hybrid inorganic-organic silica-ODS phase (XTerra RP-18, 15 cm x 0.46 cm) showed substantial loss in efficiency when sample masses exceeded about 0.5 microg; these results were similar to those obtained previously on pure silica ODS and wholly polymeric phases, suggesting a common overloading mechanism. At pH 7-8.5, substantial improvements in loading capacity were obtained on XTerra due apparently to the unexpectedly strong influence of small decreases in solute ionisation. Data from the quaternary compounds suggested that silanol ionisation on this phase was still small even at intermediate pH. For many bases, loading capacity continued to improve as the pH was raised to 10, in line with the decrease in the proportion of ionised solute. However, for the highest pK(a) solutes, peak shape worsened at high pH, possibly due to the negative influence of increasing column silanol ionisation.

Amitriptyline↗
PubMed2006

Surface-active antifungal polyquaternary amine.

There is a distinct need for antimicrobial compounds that can act at surfaces without leaching into the environment. Such materials should be easy to synthesize, be easy to apply to surfaces, and display reasonable levels of antimicrobial and antifungal activity. Here we describe such a surface-active compound and demonstrate its ability to inhibit the growth of the filamentous fungus Aspergillus niger. We have synthesized a series of polyquaternary ammonium compounds by atom transfer radical polymerization. Two members of this series were tested for their ability to inhibit the growth of A. niger. The compounds were dried onto surfaces, and the treated surfaces were then used as growth chambers for A. niger. A water soluble polyquaternary amine compound was shown to effectively kill A. niger in solution in a dose-dependent manner. Conversely, a water insoluble polyquaternary amine compound was shown to kill only the fungi in direct contact with the material on the surface. These results have important implications for the development of effective, environmentally benign, surface-active anti-fungal compounds.

Amines↗
PubMed2004

Evaluation of mechanisms of azinphos-methyl resistance in the codling moth Cydia pomonella (L.).

Resistance of the codling moth Cydia pomonella (L.) to azinphos-methyl is not based on enhanced detoxifying enzymes like oxidation mediated by mixed function oxidases or by glutathione S-transferases. Synergism by S,S,S-tributylphosphoro-trithioate was evident, but the overall activity of general esterases using p-nitrophenyl acetate as the substrate was similar in resistant and susceptible insects. In comparison to acetylcholinesterase (AChE) from susceptible adult codling moth, the enzyme of insects resistant to azinphos-methyl has low affinities (higher K(m) values) to the substrates acetylthiocholine (ATCh) and propionylthiocholine. This difference indicates a possible amino acid alteration at the catalytic or anionic binding sites of the resistant enzyme. Inhibition studies revealed no apparent differences in sensitivity of AChE enzymes from resistant and susceptible moths to organophosphorus compounds (OPs), carbamate insecticides and quaternary ammonium ligands. MEPQ (7-Methylethoxyphosphinyloxy)-1-methylquinolinium) is the most powerful OP inhibitor acting at a nM range, while chlopyrifos oxon, azinphos-methyl oxon and paraoxon are less inhibitory by 22.9, 82.3 and 475 fold, respectively. The codling moth AChE is a typical enzyme that displays substrate inhibition by ATCh, negligible hydrolysis of butyrylthiocholine, very high sensitivity to the bisquaternary ammonium compound BW284c51 and it is not inhibited by the powerful butyrylcholinesterase inhibitor iso-OMPA. Of the three carbamates examined, only carbaryl was inhibitory at the mM range while pirimicarb and aldicarb were inactive. Of the quaternary ammonium ligands (except for the powerful BW284c51), edrophonium and decamethonium displayed appreciable inhibition rates, while d-tubocuraine was practically inactive.

Acetylcholinesterase↗
PubMed1988

Rapid pre-operative immunotherapy in a patient allergic to muscle relaxants.

Allergic reactions to muscle relaxants are not uncommon. Although, in most instances, divalent quaternary ammonium salts are involved in these reactions, some monovalent quaternary ammonium compounds can trigger IgE-mediated reactions. A woman who suffered from several episodes of anaphylaxis with divalent (suxamethonium) and monovalent quaternary ammonium salts (tiemonium) needed surgery. Regional anaesthesia was contra-indicated owing to a possible intolerance to local anaesthetics. Investigation confirmed an allergy to monovalent quaternary ammonium salts. Rapid immunotherapy was started with a monovalent quaternary ammonium salt (tiemonium) and subsequently followed by a general anaesthesia using vecuronium. The patient did not develop anaphylactic symptoms.

Adult↗
PubMed2000

The C-F...cation interaction: an ammonium complex of a hexafluoro macrocyclic cage compound.

An ammonium complex of the hexafluoro cage compound 1 was isolated and its structure was elucidated by X-ray crystallographic analysis. The C-F bonds are elongated by the complexation, which is clear evidence of C-F...cation interaction. The driving force of NH4(+) inclusion is the C-F cation interaction, but the C-F...HN+ hydrogen bond does not contribute to this complexation. The crystal structure of the NH4+ complex 1 shows short C-F...HN+ contacts (2.286-2.662 A). Furthermore, it shows that closer F...H(+)(-N) distances give a larger F...H(+)-N angle. Although such structural features seem to indicate the existence of C-F...HN+ hydrogen bonds, the spectral data (1H NMR, 19F VT-NMR, and IR spectroscopy) did not support the existence of hydrogen bonds. Thermodynamic parameters, log K(s) (4.6 +/- 0.1, 298 K), deltaH (-5.3 +/- 0.1 kcal mol(-1)), and deltaS (3.2 +/- 0.3 cal mol(-1) K(-1)), of the complexation were obtained in CDCl3/CD3CN mixture.

Cations↗
PubMed1999

Transporters for ammonium, amino acids and peptides are expressed in pitchers of the carnivorous plant Nepenthes.

Insect capture and digestion contribute substantially to the nitrogen budget of carnivorous plants. In Nepenthes, insect-derived nitrogenous compounds are imported from the pitcher fluid and transported throughout the plant via the vascular tissue to support growth. Import and distribution of nutrients may require transmembrane nitrogen transporters. Representatives of three classes of genes encoding transporters for the nitrogenous compounds ammonium, amino acids and peptides were identified in Nepenthes pitchers. The expression at the cellular level of an ammonium transporter gene, three amino acid transporter genes, and one peptide transporter gene were investigated in the insect trapping organs of Nepenthes. Expression of the ammonium transporter gene NaAMT1 was detected in the head cells of digestive glands in the lower part of the pitcher where NaAMT1 may function in ammonium uptake from the pitcher fluid. One amino acid transporter gene, NaAAP1, was expressed in bundle sheath cells surrounding the vascular tissue. To understand the locations where transmembrane transport could be required within the pitcher, symplasmic and apoplasmic continuity was probed using fluorescent dyes. Symplasmic connections were not found between cortical cells and vascular bundles. Therefore, the amino acid transporter encoded by NaAAP1 may be involved in transport of amino acids into the vascular tissue. In contrast, expression of the peptide transporter gene NaNTR1 was detected in phloem cells of the vascular tissue within pitchers. NaNTR1 may function in the export of nitrogen from the pitcher by loading peptides into the phloem.

Amino Acid Sequence↗
PubMed1975

Complex formation between menadione and cetylethylmorpholinium ethosulfate: effect on UV photodegradation of menadione.

The process of menadione photodegradation can be enhanced or diminished by other compounds. The presence of the quaternary ammonium compound cetylethylmorpholinium ethosulfate (I) in solutions of minadione was found to slow the rate of photodegradation by UV light (253.7 nm). The mechanism of this effect may be due to complex formation between menadione and I. Complex formation was demonstrated by a shift in the absorption peaks of menadione from 245 and 260 nm to 251.5 and 261.5 nm, respectively. The equilibrium constant of this complex was calculated to be 1.647 M.

Kinetics↗
PubMedDate not supplied

Capillary electrophoresis and liquid chromatography in the analysis of some quaternary ammonium salts used in lozenges as antibacterial agents.

A comparison is made of the relative merits of high-performance liquid chromatography and capillary electrophoresis, both using direct UV detection, for the determination of three quaternary ammonium compounds used as the active antibacterial ingredient in lozenge formulations. While both techniques are capable of separating the compounds cetylpyridinium chloride, dequalinium chloride, and benzalkonium chlorides, the liquid chromatographic method involving ion pairing and using a 5-micron cyanopropyl stationary phase, was unable to resolve the benzalkonium chlorides from the lozenge excipients and quantitation was not possible. The capillary electrophoresis method using a 205-mm 50-micron-i.d. capillary with a running buffer of 50% vol/vol 50 mM phosphate buffer at pH 3 provided superior resolution of the three antibacterials in all lozenge formulations. This system was also capable of resolving impurities in the dequalinium chloride both in the standard and in lozenges containing this compound. On the basis of quantitative results previously published, both methods have adequate validation parameters since the relative insensitivity of capillary electrophoresis compared with liquid chromatography is not important at the concentration required to be determined following a single simple sample pretreatment.

Anti-Infective Agents↗
PubMed1987

Hair bulb accumulation of Langerhans cells in allergic patch tests.

The occurrence of occupational allergic contact dermatitis due to 2,3-epoxypropyl trimethyl ammonium chloride (EPTMAC) is reported and supplemented with immunohistochemical and electron microscopic observations. Four young workers developed hand dermatitis at a factory in which modified, cationic starch is manufactured. EPTMAC, a quaternary ammonium compound used as a cationizing chemical in the process, produced allergic reactions in all four patients in epicutaneous testing. The patients had only been in contact with EPTMAC for a short time (one to three months) before developing allergic eczema, which indicates that EPTMAC is a strong sensitizer. Immunohistochemistry showed that dendritic OKT6+ cells (Langerhans cells) increase in the hair follicles and the peribulbar infiltrate during the allergic patch test indicating that hair follicles might actively be involved in delayed type allergic reactions, possibly as a shunt way for allergens. Using electron microscopy, mitotic immunocompetent cells were found in the epidermis during the allergic patch test.

Azo Compounds↗
PubMed1997

Trapping of organic blockers by closing of voltage-dependent K+ channels: evidence for a trap door mechanism of activation gating.

Small organic molecules, like quaternary ammonium compounds, have long been used to probe both the permeation and gating of voltage-dependent K+ channels. For most K+ channels, intracellularly applied quaternary ammonium (QA) compounds such as tetraethylammonium (TEA) and decyltriethylammonium (C10) behave primarily as open channel blockers: they can enter the channel only when it is open, and they must dissociate before the channel can close. In some cases, it is possible to force the channel to close with a QA blocker still bound, with the result that the blocker is "trapped." Armstrong (J. Gen. Physiol. 58:413-437) found that at very negative voltages, squid axon K+ channels exhibited a slow phase of recovery from QA blockade consistent with such trapping. In our studies on the cloned Shaker channel, we find that wild-type channels can trap neither TEA nor C10, but channels with a point mutation in S6 can trap either compound very efficiently. The trapping occurs with very little change in the energetics of channel gating, suggesting that in these channels the gate may function as a trap door or hinged lid that occludes access from the intracellular solution to the blocker site and to the narrow ion-selective pore.

Animals↗
PubMed1961

Evaluation of disinfection techniques for, and their effects on, rectal thermocouple catheters.

The antibacterial activities of an iodophor (Wescodyne G), a quaternary ammonium compound (Roccal), and an iodine tincture as agents for the cold disinfection of rectal catheters contaminated in vitro were determined. Following thorough cleaning with an alcoholic solution of soft soap, each of the three disinfectants tested showed satisfactory results (100% kill) in 5 min against the enteric test bacteria (Escherichia coli and Salmonella typhosa) as well as a test species of the genus Pseudomonas, among the bacteria most resistant to surface-active agents. An aqueous solution of Wescodyne G containing 75 ppm available iodine was used both as a wiping solution and for subsequent disinfection of rectal catheters contaminated in vivo. Total bacterial destruction was found to follow a 60-min soak preceded by the wiping procedure. Rectal catheters subjected to prolonged immersion in each of the test disinfectants were found to be essentially unaffected, retaining their initial calibrations within a permissible tolerance. Neither Roccal nor Wescodyne G solutions were found to measurably attack bare thermocouples. Alcoholic iodine 0.5% did, however, exert a deteriorating effect on bare thermocouples in a short time, as measured by change in resistance characteristics. The results of this study have led to the recommendation that Wescodyne G containing 75 ppm available iodine be used in standing operating procedures for the initial cleaning and subsequent disinfection of rectal thermocouple catheters.

Benzalkonium Compounds↗
PubMed1969

Acetylcholine receptor: covalent attachment of depolarizing groups at the active site.

Following reduction of the acetylcholine receptor in the electroplax with dithiothreitol, the quaternary ammonium compounds bromoacetylcholine bromide and the p-nitrophenyl ester of (p-carboxyphenyl) trimethylammonium iodide react near the active site probably with a sulfhydryl group. The covalently attached quaternary ammonium moieties additionally interact with the active site noncovalently to activate the receptor and cause depolarization of the cell.

Acetylcholine↗
PubMed1987

A surface test for virucidal activity of disinfectants: preliminary study with herpes virus.

A test was developed to assess the surface activity of disinfectants against dried viral preparations. In this preliminary study a variety of disinfectants was tested against herpes virus. The results showed that 2% alkaline glutaraldehyde and 70% ethanol or isopropanol were effective in 1 min. Hypochlorite solutions (2500 ppm av. Cl2) were effective in 5 min, but povidone-iodine (10%) was slower in action and a clear soluble phenol showed uncertain activity at 5 and 10 min. High concentrations of alcohols (above 95%), two quaternary ammonium compounds and 0.5% aqueous chlorhexidine showed little activity in 10 min.

Alcohols↗