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PubMed1983

Whole body distribution of the quaternary ammonium compound thiazinamium (N-methylpromethazine) and promethazine in monkey and mice.

The distribution of 35S-ringlabeled thiazinamium (N-methyl-promethazine) methylsulphate (35S-Th.) and its tertiary analog 35S-promethazine hydrochloride (35S-Pr.) have been studied by means of whole body autoradiography in a squirrel monkey and in mice. After infusion of 35S-Th. in the monkey until steady state condition, high accumulations of radioactivity were found in the three main organs of excretion of the drug (liver, kidneys and intestines). High concentrations of radioactivity were also observed in organs with high amounts of acetylcholine receptor such as the ganglia, skeletal muscles, myocard and ciliary bodies, and in glandular tissue such as salivary glands, thyroid gland and pancreas. On the other hand no radioactivity was seen in the central nervous system with exception of the posterior pituitary gland and the fourth ventricle. This suggests that Th.-cations cannot pass "the blood-brain barrier", except for some high permeability regions that are known to be "windows" in this barrier. 35S-Pr. was distributed significantly different. Now a high level of radioactivity was seen in the central nervous system, indicating that the tertiary amine compound can easily pass "the blood-brain barrier". Again high concentrations of radiation were found in liver, kidneys and intestines. 35S-Pr. also seemed to penetrate to acetylcholine receptor areas. Substantial accumulation in the eye was seen, as well as in glandular tissues. Essentially the same distribution patterns as described above were seen for 35S-Th. and 35S-Pr. after intramuscular injection in mice. In pregnant mice, after administration of 35S-Th. high concentration of radioactivity was found in the placenta, but only low amounts were seen in the foetus, and then only in the liver and the kidneys, which implies that Th.-cations can pass the placenta, however, to a low extent and at a low rate. With 35S-Pr. obviously placenta transfer can occur more easily and distribution in the foetus is not restricted to the liver and kidneys.

Animals↗
PubMed1976

Ion-pair extraction method for quantitation of a bisquaternary ammonium compound, pancuronium bromide.

Pancuronium bromide (PCBr), a neuro-muscular blocking agent, was determined quantitatively in aqueous solution by ion-pair extraction. Separate determination of PCBr and degradation products was possible after thin layer chromatography. The procedure was developed by using a theoretical approach. Favorable conditions were calculated from the ion-pair extraction constant. The drug was determined with bromothymol blue at pH 9.0, using one extraction in the direct procedure and 2 successive extractions in the combined elution-extraction process after thin layer chromatography. In the direct method, 0.100 mg PCBr was determined with a reproducibility of +/- 1.0%.

Chromatography, Thin Layer↗
PubMed1993

Stimulatory effect of cooling tower biocides on amoebae.

Two species of amoebae were isolated from the cooling tower of an air-conditioning system and examined for effects of exposure to four cooling tower biocides, a thiocarbamate compound, tributyltin neodecanoate mixed with quaternary ammonium compounds, another quaternary ammonium compound alone, and an isothiazolin derivative. The amoebae isolated were Acanthamoeba hatchetti and a Cochliopodium species. Two other amoeba cultures, an A. hatchetti culture and Cochliopodium bilimbosum, were obtained from the American Type Culture Collection (ATCC) and were also tested. The cooling tower isolates were more resistant to most of the biocides than the ATCC isolates were. The isothiazolin derivative was the least inhibitory to all four amoeba isolates, and tributyltin neodecanoate mixed with quaternary ammonium compounds was the most inhibitory to three of the four isolates. After exposure to lower concentrations of the biocides, including for one strain the manufacturer's recommended concentration of one biocide, the cooling tower amoeba populations increased significantly compared with unexposed controls, whereas the ATCC isolates were not stimulated at any of the concentrations tested. In some cases, concentrations which stimulated cooling tower amoebae inhibited the growth of the ATCC isolates. These results suggest that cooling tower amoebae may adapt to biocides, underscoring the need to use freshly isolated cooling tower organisms rather than organisms from culture collections for testing the efficacy of such biocides. The stimulatory effect of biocides on amoeba populations is an alarming observation, since these organisms may be reservoirs for legionellae. Biocides used to control microbial growth may actually enhance populations of host organisms for pathogenic bacteria.

Acanthamoeba↗
PubMed1971

Injury of bacteria by sanitizers.

Injury of test cultures was quantitated by differences in colony counts obtained with a complete medium and those obtained on conventional selective media. Staphylococcus aureus, Streptococcus faecalis, and several strains of Escherichia coli were injured when exposed to the quaternary ammonium compound methylalkyltrimethyl ammonium chloride. Representative hypochlorite sanitizers also caused injury of E. coli ML30. Sanitizer concentration appeared to be the main factor in the cause of death and injury, a higher concentration being needed to cause death. Increases in temperature did not result in substantial increases in injury; however, the lethal effect was greater at higher temperatures. Varying the cell concentration from 10(7) to 10(9) cells per ml did not change the fraction of cell population killed or injured. The inability or failure of common selective media to detect injured bacteria in food could have serious public health consequences.

Chlorine↗
PubMed2005

Incidence of class 1 integrons in a quaternary ammonium compound-polluted environment.

Samples of effluent and soil were collected from a reed bed system used to remediate liquid waste from a wool finishing mill with a high use of quaternary ammonium compounds (QACs) and were compared with samples of agricultural soils. Resistance quotients of aerobic gram-negative and gram-positive bacteria to ditallowdimethylammomium chloride (DTDMAC) and cetyltrimethylammonium bromide (CTAB) were established by plating onto nutrient agar containing 5 microg/ml or 50 microg/ml DTDMAC or CTAB. Approximately 500 isolates were obtained and screened for the presence of the intI1 (class 1 integrase), qacE (multidrug efflux), and qacE Delta1 (attenuated qacE) genes. QAC resistance was higher in isolates from reed bed samples, and class 1 integron incidence was significantly higher for populations that were preexposed to QACs. This is the first study to demonstrate that QAC selection in the natural environment has the potential to coselect for antibiotic resistance, as class 1 integrons are well-established vectors for cassette genes encoding antibiotic resistance.

Bacteria↗
PubMed2001

Distinct mechanisms of block of Kv1.5 channels by tertiary and quaternary amine clofilium compounds.

The quaternary ammonium compound clofilium and its tertiary amine derivative LY97241 were used to analyze mechanisms of block in a voltage-gated potassium channel. Wild-type and mutant Kv1.5 channels expressed in Xenopus oocytes were recorded by two-electrode voltage clamp. Open-channel block to 20% of the control current amplitude was induced reversibly by 50 microM clofilium or 200 microM LY97241, and was seen as an acceleration of the macroscopic current decay. Although blockers remained present after application, channels recovered from block during each interpulse interval. The optimum voltage for recovery (-45 mV at pH 7.3) at the threshold for channel activation indicated that clofilium block and recovery occurred principally through the open channel state. In contrast, LY97241 appeared to exit from the closed state and the open state. In an acid-tolerant Kv1.5 mutant channel (H452Q), external pH was used to titrate LY97241. At low pH, which protonates the LY97241 amine group, recovery from block at hyperpolarized potentials was impaired in a manner similar to that seen with clofilium. Recovery from clofilium block was reduced at negative potentials independent of pH, an effect attributed to trapping of the permanently charged compound within the closed channels.

Animals↗
PubMed2003

Adaptive and cross-adaptive responses of persistent and non-persistent Listeria monocytogenes strains to disinfectants.

Persistent and non-persistent Listeria monocytogenes strains were tested for initial resistance and adaptive and cross-adaptive responses towards two quaternary ammonium compounds, alkyl-benzyl-dimethyl ammonium chloride and n-alkyldimethyl ethylbenzyl ammonium chloride, one tertiary alkylamine, 1,3-propanediamine-N-(3-aminopropyl)N-dodecyl, sodium hypochlorite and potassium persulphate. The initial resistance of two persistent and two non-persistent L. monocytogenes strains was observed to differ. Both types of strains adapted after a 2-h sublethal exposure to the quaternary ammonium compounds and the tertiary alkylamine, the highest increase in the minimum inhibitory concentration (MIC) being 3-fold. Progressively increasing disinfecting concentrations at 10 and 37 degrees C resulted in adaptation of L. monocytogenes to all disinfectants except potassium sulphate. The highest observed increase in MIC was over 15-fold, from 0.63 to 10 microg/ml of n-alkyldimethyl ethylbenzyl ammonium chloride. All strains reached approximately similar MICs. Stability of the increased resistance was tested by measuring MICs every seventh day for 28 days. The increased resistance to sodium hypochlorite disappeared in 1 week, but the quaternary ammonium compounds and the tertiary alkylamine showed increased resistance for 28 days. These results suggest that cellular changes due to adaptive responses continue to have an effect on the resistance some time after the exposure. All disinfectants were shown to cause cross-adaptation of L. monocytogenes, the highest increase in MIC being almost 8-fold. The only agent that L. monocytogenes could not be shown to cross-adapt to was potassium persulphate which did, however, cause cross-adaptation to the other disinfectants. The mechanism behind these adaptive responses seemed to be non-specific as cross-adaptation was observed not only between related but also unrelated disinfectants. These findings suggest that sustaining high disinfectant effectiveness may be unsuccessful by rotation, even when using agents with different mechanisms of action.

Adaptation, Physiological↗
PubMed1984

Hepatic uptake and biliary excretion of organic cations--I. Characterization of three new model compounds.

Three quaternary ammonium compounds (QACs) with different lipophilicity, triethylmethyl ammonium iodide (TEMA), tripropylmethyl ammonium iodide (TPMA) and tri-n-butylmethyl ammonium iodide (TBuMA) were given as a bolus injection of 10 mumole and 1 mumole in an isolated perfused liver. TPMA and TBuMA exhibited saturation kinetics at a dose of 10 mumole, but not when 1 mumole of the agents was given. Biliary clearance of TEMA was equal to the bile flow (0.010 ml/min), whereas for TPMA and TBuMA much higher values of 0.8 ml/min and 2.2 ml/min were found respectively. Partition coefficients of TEMA, TPMA and TBuMA between n-octanol and Krebsbicarbonate solution were 0.0013, 0.013 and 0.14 respectively. Liver-to-plasma concentration ratios were 4, 16 and 30 in the post-distribution phase, whereas bile-to-liver ratios were calculated to be 0.1, 1.3 and 14 respectively. The latter parameter varied roughly proportionally to the lipophilicity of the compounds. The liver/plasma concentration ratios corrected for intracellular binding exceeded a value of 12 indicating that accumulation in the liver of these agents cannot soley be explained by passive equilibration according to the membrane potential. Transport from liver into the bile of TPMA and TBuMA presumably also occurred against an electrochemical gradient. It was inferred that the small molecular weight compounds such as TEMA, can be transported from plasma into bile paracellularly by a passive process. Rapid uptake into the liver of such compounds may not lead to an appreciable biliary output and can even reduce the rate of biliary excretion. QACs with intermediate or high lipophilicity are transported by carrier mediated processes both at the level of hepatocyte uptake and bile canalicular transport. The influence of choleresis on hepato-biliary transport of the three QACs was investigated by giving sodium taurocholate (Tc) by constant infusion of 60 mumole/hr, increasing bile flow from 9 to 16 microliter/min. The biliary output of TEMA appeared to be basically unaffected, whereas the biliary excretion of TPMA and TBuMA was clearly elevated when the bile flow was increased. The stimulatory influence of taurocholate on the biliary output of the latter organic cations is explained by an increased net uptake of these agents into the liver and an increased net canalicular transport. This effect is proposed to be due to a reduced reabsorption from the biliary tree as a consequence of the higher bile flow and/or biliary micelle binding. Taurocholate increased liver-to-plasma ratios.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1998

Molecular modelling and footprinting studies of DNA minor groove binders: bisquaternary ammonium heterocyclic compounds.

We report new quantitative footprinting data which reveal differences in binding constants of bisquaternary ammonium heterocyclic compounds (BQA) with AT-rich DNA sites depending on the ligand structure and on the size and sequence of the DNA binding site. In an attempt to understand the dependence of binding affinity on the ligand structure we have performed quantum-chemical AM1 calculations on the BQA compounds and on subunits to explore the conformational space and to calculate the electronic and structural features of individual ligand conformations. Due to the properties of the rotatable backbone bonds, there is a large number of possible conformations with almost equal energy. We present a new method for the calculation of the radius of curvature of molecular structures. Assuming that strong binders should have a shape complementary to the DNA minor groove, this measure is used to select the optimum conformations for DNA-drug binding. The approach yields the correct ligand conformation for SN6999, for which an X-ray DNA-drug structure is known. The curvature of the optimum conformations of all ligands is compared with the experimental binding constants. A correlation is found between curvature and binding constant provided other structural factors do not vary. Therefore, we conclude that within structurally similar BQA compounds the extent of curvature is the relevant quantity which modulates the binding affinity.

DNA↗
PubMed1991

Inactivation of Mycobacterium tuberculosis and Mycobacterium bovis by 14 hospital disinfectants.

Epidemics of mycobacteria due to contamination of medical devices continue to occur. For this reason, we assessed the ability of disinfectants, generally used in hospitals for disinfecting noncritical and semicritical patient care items, to inactivate mycobacteria. A modified Association of Official Analytical Chemists' (AOAC) Tuberculocidal Activity Test, using Middlebrook 7H9 broth as the primary subculture medium and neutralization by dilution, was used to assess the ability of 14 hospital disinfectants to inactivate about 10(6) Mycobacterium tuberculosis and about 10(5) Mycobacterium bovis at 20 degrees C using 10- or 20-minute exposure. All products were tested for each organism using 10 penicylinders (P) and were prepared at the manufacturers' recommended use-dilution. Chlorine dioxide, 0.80% hydrogen peroxide plus 0.06% peroxyacetic acid, and an iodophor achieved complete inactivation (0 + P) of both M. tuberculosis and M. bovis. One quaternary ammonium compound with a tuberculocidal label claim, a quaternary ammonium compound without a tuberculocidal label claim, chlorine (approximately 100 ppm) and 0.13% glutaraldehyde/0.44% phenol/0.08% phenate were not effective (10 + P) against both M. tuberculosis and M. bovis. Another quaternary ammonium compound with a tuberculocidal label claim was tested against only M. bovis and found ineffective (10 + P). Glutaraldehydes (2% alkaline and 2% acid), a phenolic and chlorine (approximately 1,000 ppm) demonstrated complete inactivation of M. tuberculosis (0 + P) and good inactivation of M. bovis (1-3 + P). Two disinfectants, hydrogen peroxide and ethyl alcohol, provided differing results against M. tuberculosis and M. bovis. These studies have important implications for disinfecting semicritical patient care items.

Chlorine↗
PubMedDate not supplied

[The intensification of biological nitrogen fixation by using ammonium carbonate compounds and the routes of their action on microorganisms and plants].

The intensification of activity of associative and symbiotic nitrogen fixation while using low amounts of ammonium-carbonate compounds, carbonic-ammonium salts, in particular, has been established. The main ways and mechanisms of the action of ammonium-carbonate salts as a new and perspective agrochemical on physiological and biochemical processes of microorganisms and agricultural plants were presented on the basis of the analysis of literary information and the author's investigations.

Agrochemicals↗