Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Dimethylamines”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed1982

Mechanistic studies on the dehydrogenases of methylotrophic bacteria. 2. Kinetic studies on the intramolecular electron transfer in trimethylamine and dimethylamine dehydrogenase.

E.p.r. spectroscopy of the trimethylamine and dimethylamine dehydrogenases of Hyphomicrobium X indicates that the substrate-reduced forms of these enzymes exist in the triplet state, which arise through interaction of a reduced [4Fe-4S] cluster and flavosemiquinone, with e.p.r. signals which differ in detail from those of the trimethylamine dehydrogenase of bacterium W3A1. Under certain conditions the intramolecular electron transfer between the flavoquinol form of 6-S-cysteinyl-FMN and the [4Fe-4S] cluster in all three dehydrogenases was much slower than the preceding reduction of the flavin to the flavoquinol form. Trimethylamine dehydrogenases from both organisms show a time-dependent broadening of the e.p.r. signals centred around g = 2 after mixing with trimethylamine. The broadening of the e.p.r. signals could be correlated with an unexpected dependence of the rate of formation of the triplet state on substrate concentration. A model which accounts in a qualitative manner for the substrate dependence of the formation of the triplet state in the trimethylamine dehydrogenase of Hyphomicrobium X is proposed. The binding of the substrate to the reduced form of the enzyme seems to result in a conformational change of the enzyme to a form in which the rate of intramolecular electron transfer is decreased. This finding may be correlated with the observation of hyperbolic substrate inhibition for both trimethylamine dehydrogenases. The results indicate the transfer of an electron to the [4Fe-4S] cluster to be an obligatory step in catalysis and suggest that the transfer of electrons from these enzymes to electron acceptors is mediated solely through the [4Fe-4S] cluster.

Bacteria↗
PubMed2003

Activity of the amidoamine myristamidopropyl dimethylamine against keratitis pathogens.

OBJECTIVES: Microbial keratitis accounts for up to 30% of blindness in some less developed societies. The development of a single broad-spectrum topical antimicrobial effective against bacteria, fungi and Acanthamoeba would have a major impact on reducing the morbidity and simplifying the treatment of microbial keratitis. To this end, the activity of the amidoamine myristamidopropyl dimethylamine (MAPD) was investigated against common causes of microbial keratitis. METHODS: Challenge test assays were used to study the efficacy of 50 mg/L MAPD against Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, Fusarium solani and Acanthamoeba polyphaga. RESULTS: MAPD gave a 3.7 log kill of P. aeruginosa after 60 min, 5.4 log for S. aureus by 45 min and 5 log for C. albicans and F. solani within 15 min. A. polyphaga cysts were reduced by 4 log within 120 min. CONCLUSIONS: The findings of this study confirm that MAPD is an effective Acanthamoeba cysticidal agent and extend the observation to demonstrate that it also possesses excellent antifungal and antibacterial activity. MAPD may represent a broad-spectrum therapeutic antimicrobial for keratitis and surgical prophylaxis and deserves further evaluation in these roles.

Acanthaceae↗
PubMed1984

Subcellular localization and properties of partially purified dimethylamine and trimethylamine mono-oxygenase activities in Candida utilis.

By techniques involving differential centrifugation and specific precipitation with CaCl2, it was shown that dimethylamine and trimethylamine mono-oxygenase activities co-sediment with NADPH-cytochrome c reductase activity in sphaeroplast lysates of Candida utilis grown on trimethylamine as sole nitrogen source. Since the active fraction also contained low levels of cytochromes P-450 and P-420, it was concluded that the two amine mono-oxygenases are located in the smooth endoplasmic reticulum and thus end up in the microsomal fraction on cell fractionation. Ten to twenty-fold enrichment of mono-oxygenase specific activity could be achieved by separation of activity from soluble protein by centrifugation or gel filtration. Cell-free extracts prepared in the absence of FAD showed only very low mono-oxygenase activity for either substrate. Some activity could be restored by addition of flavin nucleotides: there was a fivefold stimulation by FAD and a fourfold stimulation by FMN. All trimethylamine mono-oxygenase activity was lost when a partially purified preparation containing both activities was incubated for more than 24 h at 0 degrees C, suggesting that separate enzymes are responsible for the oxidation of secondary and tertiary amines. The enzyme preparation oxidized a wide range of secondary alkylamines up to dibutylamine and tertiary alkylamines up to tributylamine. Primary amines, choline, di- and triethanolamine, spermine, spermidine and substituted anilines were not oxidized. NADH had a lower apparent Km value and higher Vmax value than NADPH. Secondary and tertiary alkylamines containing more than one kind of alkyl group gave more than one kind of aldehyde on oxidation. Stoicheiometry determinations showed a consumption of 1 mol NAD(P)H and 1 mol O2 per mol aldehyde formed. Carbon monoxide, cyanide, proadifen hydrochloride (SKF 525-A), mercurials and mercaptoethanol all inhibited both activities.

Candida↗
PubMed2000

Antimicrobial evaluation of N-alkyl betaines and N-alkyl-N, N-dimethylamine oxides with variations in chain length.

Alkyl betaines and alkyl dimethylamine oxides have been shown to have pronounced antimicrobial activity when used individually or in combination. Although several studies have been conducted with these compounds in combinations, only equimolar concentrations of the C(12)/C(12) and C(16)/C(14) chain lengths for the betaine and the amine oxide, respectively, have been investigated. This study investigates the antimicrobial activity of a wide range of chain lengths (C(8) to C(18)) for both the betaine and amine oxide and attempts to correlate their micelle-forming capabilities with their biological activity. A broth microdilution method was used to determine the MICs of these compounds singly and in various molar ratio combinations. Activity against both Staphylococcus aureus and Escherichia coli was investigated. Antimicrobial activity was found to increase with increasing chain length for both homologous series up to a point, exhibiting a cutoff effect at chain lengths of approximately 16 for betaine and 14 for amine oxide. Additionally, the C(18) oleyl derivative of both compounds exhibited activity in the same range as the peak alkyl compounds. Critical micelle concentrations were correlated with MICs, inferring that micellar activity may contribute to the cutoff effect in biological activity.

Anti-Bacterial Agents↗
PubMed2004

Allergic contact dermatitis from cocamidopropyl betaine, cocamidoamine, 3-(dimethylamino)propylamine, and oleamidopropyl dimethylamine: co-reactions or cross-reactions?

We present the case of a patient with facial dermatitis caused by sensitization to cocamidopropyl betaine. The patient also had positive patch-test reactions to cocamidoamine, 3-(dimethylamino)propylamine, and oleamidopropyl dimethylamine. The presence of 3-(dimethylamino)propylamine as an impurity in all of these substances can be hypothesized to explain these simultaneous reactions.

Adult↗
PubMed1985

The acute toxicity and primary irritancy of N-benzyl-N,N-dimethylamine.

N-Benzyl-N,N-dimethylamine (BDMA), a polyester foam catalyst, was determined to have LD50 values of 0.65 (0.48-0.88) ml/kg perorally in the rat, and 1.66 (1.35-2.04) ml/kg by 24-hr occluded dermal contact in rabbits. The Lt50 for saturated vapor atmosphere exposure of rats was 35.4 min, and the 4-hr LC50 was 373 (311-447) ppm for rats and mice. Histological examination of the respiratory tract of animals exposed to BDMA concentrations of 277 ppm or higher revealed acute inflammatory changes in the nasal mucosa and pulmonary congestion. Unoccluded skin contact with 0.01 ml undiluted BDMA in rabbits produced moderate local erythema and edema. A 4-hr occluded contact resulted in local necrosis. Severe eye irritancy was produced by 0.005 ml undiluted BDMA and 0.5 ml 5% BDMA in propylene glycol; 1% BDMA was nonirritant to the eye. BDMA should be regarded as an acutely hazardous material by all routes of exposure.

Administration, Oral↗
PubMed1976

Experiments on the detection of the carcinogenic N-nitroso-dimethylamine in the urine of rats after oral administration of the analgesic amidopyrine and nitrite.

N-Nitroso-dimethylamine (NDMA) was excreted unchanged in the urine of rats after oral administration of the compound in amounts ranging from 0.003% at a dose of 2 mg/kg to 0.08% at a dose of 15 mg/kg. By measurement of the NDMA excreted after oral administration of amidopyrine and nitrite, the extent of nitrosation in vivo was estimated to be about 30%. For clinical investigation of NDMA formation in patients treated with amidopyrine, however, we consider this method to be too insensitive.

Aminopyrine↗
PubMedDate not supplied

Evidence for a fast repair of apurinic sites induced by N-nitroso-dimethylamine in rat liver DNA.

Sprague Dawley male rats were treated with N-nitroso-dimethylamine and the damage induced in liver DNA was investigated using the in vivo DNA alkaline elution assay. Determination of the number of single stranded breaks after different incubation periods in alkali showed that most of them (approximately equal to 95%) were alkali-labile sites, with a half-life of about 33 min, as expected for apurinic sites. The extent of DNA methylation was calculated, by assuming depurination of N-7-methylguanine to be the rate-limiting step for breakdown of DNA. The amount of DNA fragmentation observed accounted for only one fifth of N-7-methylguanine. The calculation could be made to correspond to the extent of methylation determined experimentally, by assuming the occurrence of a fast repair in vivo of apurinic sites (t1/2 approximately equal to 18 min). Our hypothesis of a fast repair of apurinic sites is in agreement with the analysis of data of Peterson et al. (1974). Moreover, the rate of repair required by the level of spontaneous depurination of normal guanine at neutral pH and 37 degree C, agrees satisfactorily with our estimations.

Animals↗
PubMed1992

Oral and dermal application of 2,4-dichlorophenoxyacetic acid sodium and dimethylamine salts to male rats: investigations on absorption and excretion as well as induction of hepatic mixed-function oxidase activities.

Absorption and urinary excretion of 2,4-dichlorophenoxyacetic acid sodium (sodium 2,4-D) and 2,4-dichlorophenoxyacetic acid dimethylammonium (2,4-DMA) salts were examined after single oral and mid-dorsal skin applications of the herbicides to male rats. Doses of 2.6 mg 2,4-D/kg body wt (sodium 2,4-D) and 1.9 mg 2,4-D/kg body wt (2,4-DMA) were applied. Quantitatively, with both salts, most of the orally administered herbicide (over 90%) was excreted in urine within 28 h. However, 2,4-D urinary peak concentrations were measured 4.5 and 20.5 h after dosing with 2,4-DMA and sodium 2,4-D, respectively. Additionally, the volume of urine in the oral study was significantly increased with both salts when compared with the controls or the dermal exposure. After topical application, 2,4-D absorption was much lower than in the oral study. Urinary excretion only reached about 10 and 15% of the applied dose for sodium 2,4-D and 2,4-DMA, respectively, by 5 days post-treatment. Further, we found some elevations in hepatic cytochrome P-450 activities. Ethylmorphine N-demethylase was only slightly induced by the herbicides while ethoxyresorufin O-deethylase activity was increased nearly 2-fold by sodium 2,4-D.

2,4-Dichlorophenoxyacetic Acid↗
PubMed1983

Oxidation of dimethylamine and trimethylamine in methazotrophic yeasts by microsomal mono-oxygenases sensitive to carbon monoxide.

Whole cells of Candida boidinii grown on di- or tri-methylamine as sole nitrogen source readily oxidized both amines. The oxidation was potently inhibited by carbon monoxide. Cell-free extracts required the presence of 20 microM FAD before mono-oxygenase activity with both amines could be demonstrated. NADH was a better electron donor than NADPH. Activity was present in cells grown on secondary and tertiary amines but not on primary amines, and was detected in a number of different yeasts. Enzyme activity could be sedimented at 187 000 x g, and was associated with NADPH-cytochrome c reductase activity. It is thus probably microsomal. Activity was inhibited by cyanide, mercaptoethanol, carbon monoxide and proadifen hydrochloride (SKF 525-A).

Candida↗