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PubMedDate not supplied

Amines in the marking fluid and anal sac secretion of the tiger, Panthera tigris.

Analysis of the marking fluid of two tigers (one Bengal and one Sumatran) by GC using an amine-specific column and a nitrogen-specific detector has shown the presence of the following amines: ammonia, methylamine, dimethylamine, trimethylamine, triethylamine, propylamine, and butane-1,4-diamine (putrescine). In contrast to previously published reports, we were unable to detect 2-phenylethylamine. The anal sac secretion was found to have a similar amine content.

Amines↗
PubMed2004

Quantitative structure-activity relationship modeling of acute toxicity of quaternary alkylammonium sulfobetaines to Daphnia magna.

The logarithm of the octanol/water partition coefficient has been widely used as the sole physicochemical property to define various types of biological activity, such as aquatic toxicity. In the present study, we derive a quantitative structure-activity relationship (QSAR) equation for the prediction of acute aquatic toxicity (48-h median effective concentration) of quaternary alkylammonium sulfobetaines to the aquatic invertebrate Daphnia magna Straus. The single-parameter approach described is also based on the hydrophobicity parameter, log P. The 17 zwitterionic compounds were considered for QSAR development. They have the general formula RN+(CH3)2(CH2)nSO3-, where n = 2 to 4, and were synthesized by reacting the corresponding N,N-dimethylamines with either sodium-2-chloroethanesulfonate (n = 2), 1,3-propanesultone (n = 3), or 1,4-butanesultone (n = 4). The R group was either a C6 to C12 alkyl chain, a phenylalkyl unit bearing a C1 to C4 chain, or a phenylpropyl unit with a C4 to C6 para-substituted alkyl group. Octanol/water partition coefficients were experimentally determined via a conventional stir-flask procedure, which was quantified using a reverse-phase, high-performance liquid chromatographic technique coupled with either an ultraviolet or an electrospray ionization mass spectrometry detection system. Median effective concentration values were also determined experimentally via a standard acute immobilization test recommended by Organisation for Economic Cooperation and Development (Paris, France) Guideline 202. The established QSAR equation for such zwitterionic compounds is consistent with the standard equation that normally defines the polar narcosis mode of toxic action.

Animals↗
PubMedDate not supplied

Sources and fate of nitrosodimethylamine and its precursors in municipal wastewater treatment plants.

To assess the occurrence and fate of nitrosodimethylamine (NDMA) and its precursors in wastewater treatment plants, samples from wastewater treatment plants and industrial sources were analyzed for NDMA, total NDMA precursors, and dimethylamine (DMA). The median concentration of NDMA in untreated wastewater was approximately 80 ng/L, with maximum concentrations up to 790 ng/L presumably occuring because of sources unrelated to domestic wastewater. Concentrations of DMA in untreated wastewater ranged from approximately 50 to 120 microg/L and accounted for a majority of the NDMA precursors. The removal of NDMA during secondary biological treatment exhibited considerable variability, with overall removal ranging from 0 to 75%. In contrast, removal of NDMA precursors and DMA generally exceeded 70%. The median concentration of NDMA in secondary effluent before disinfection was 46 ng/L. Although DMA was removed during secondary treatment, other NDMA precursors in wastewater effluent will result in formation of additional NDMA upon disinfection with chloramines.

Chlorine Compounds↗
PubMed1975

On the chemical basis of chromosome banding patterns.

A comparative study of the staining characteristics of four reagents for human chromosomes has been carried out. The four reagents are: (I) quinacrine mustard, as an alkylating agent, (II) the dihydroxy derivative of quinacrine mustard, (III) quinacrine, and (IV) 9-amino-6-chloro-2-methoxyacridine. The last reagent does not possess the amino substituted side chain even though it has the same intercalating nucleus. Comparison of the first three compounds in their staining and banding behavior suggested the initial step leading to banding may be the displacement of the nucleoprotein sites in hcromosomes. The Q and G banding could be blocked experimentally by treating the chromosome preparation with dimethylamine solution. This result may suggest that these sites have weaker basic proteins (nonhistone proteins?). The use of compound IV, which does not have the side chain in the molecule but does have the same intercalating chromophore, did not lead to banding and gives indirect support to this hypothesis. A combined use of compound IV and quinacrine may be useful for the determination of total DNA vs. banding DNA.

Acridines↗
PubMed2004

[An improved novel method of venlafaxine synthesis].

OBJECTIVE: To synthesize venlafaxine with an improved novel method. METHODS: p-methoxypheny lethyl-acid was reacted with SOCl(2) to produce acyl chloride which was reacted with N,N-dimethylamine solution to get amide; then through Ivanov reaction and reduction by KBH(4)/BF(3).Et(2)O to yield venlafaxine. RESULT: Venlafaxine was successfully synthesized by using this method with an yield rate of 50.3%. CONCLUSION: The improved method is suitable for industrial production of venlafaxine.

Antidepressive Agents, Second-Generation↗
PubMed2004

Interrelationships among microbiological, physicochemical, and biochemical properties of Terrincho cheese, with emphasis on biogenic amines.

Changes in the microbiological, physicochemical, and biochemical characteristics of Terrincho cheese as represented by native microflora, pH, water activity, soluble nitrogen fractions, free amino acids, and biogenic amines (e.g., ethylamine, dimethylamine, tryptamine, phenylethylamine, putrescine, cadaverine, histamine, tyramine, cystamine, and spermine) during ripening were monitored. Terrincho is a traditional Portuguese cheese manufactured from raw ewe's milk. The main groups of microorganisms (lactococci, lactobacilli, enterococci, pseudomonads, staphylococci, coliforms, yeasts, and molds) were determined following conventional microbiological procedures. Free amino acids and biogenic amines were determined by reverse-phase high-performance liquid chromatography, following extraction from the cheese matrix and derivatization with dabsyl chloride. The total content of free amino acids ranged from 1,730 mg/kg of dry matter at the beginning of the ripening stage to 5,180 mg/kg of dry matter by day 60 of ripening; such an increase was highly correlated with the increase of water-soluble nitrogen in total nitrogen, 12% trichloroacetic acid-soluble nitrogen in total nitrogen, and 5% phosphotungstic acid-soluble nitrogen in total nitrogen throughout ripening. Histamine was consistently present at very low levels, whereas putrescine, cadaverine, and tryptamine were the dominant biogenic amines and increased in concentration during ripening. Ethylamine, tryptamine, phenylethylamine, and cystamine reached maxima by 30 days of ripening and decreased thereafter. Significant correlations between amino acid precursors and corresponding biogenic amines, as well as between biogenic amines and microbial viable numbers, were observed.

Amino Acids↗
PubMed1999

Antimicrobial comparison of a new multi-purpose disinfecting solution to a 3% hydrogen peroxide system.

PURPOSE: We compared the antimicrobial activity of a new multi-purpose disinfection solution (OPTI-FREE EXPRESS with ALDOX) to a 3% hydrogen peroxide disinfecting system. The antimicrobial ingredients in the new solution are polyquaternium-1 and myristamidopropyl dimethylamine. METHODS: The solutions were tested for antimicrobial activity against Staphylococcus sp.., Pseudomonas aeruginosa, Serratia marcescens, Candida albicans, Fusarium solani, and two Acanthamoeba species and were evaluated according to the primary criteria of the FDA and ISO contact lens disinfection procedures. RESULTS AND CONCLUSIONS: OPTI-FREE EXPRESS with ALDOX (EXPRESS MPDS) Multi-Purpose Disinfecting Solution provided a multiple spectrum of antimicrobial activity and met the FDA and ISO primary Stand Alone Test criteria for disinfection of contact lenses. EXPRESS MPDS showed disinfection activity in the range of a 3% hydrogen peroxide system. Unlike the 3% hydrogen peroxide system, it retarded contamination during storage.

Bacteria↗
PubMed2000

Pharmacological limitation of damage to renal medulla after cold storage and transplantation by trimetazidine.

Delayed graft function remains an important complication after renal transplantation. In this study, we investigated the influence of trimetazidine (TMZ), a cytoprotective agent, on renal medullary damage after prolonged preservation and autotransplantation. Pig kidneys were cold-flushed and preserved (48 h at 4 degrees C) with two standard renal preservation solutions Euro-Collins and University of Wisconsin supplemented or not with TMZ (10(-6) M). Analysis of plasma and urine from 48-h-cold-stored and autotransplanted kidneys was performed with biochemical methods and proton NMR spectroscopy. Histological study by light and electron microscopy was performed after reperfusion (30-40 min) and on day 14. The results showed that the preservation in either Euro-Collins or University of Wisconsin solution containing TMZ improved significantly glomerular filtration rate compared with kidneys preserved without TMZ. TMZ significantly reduced renal medullary damage, evidenced by decreased excretion of trimethylamine-N-oxide, dimethylamine, dimethylglycine, and acetate in urine. Proximal tubular injury in TMZ-free groups was assessed by significantly greater Na(+) excretion, amino aciduria, and lactic aciduria than in TMZ-supplemented groups. Urinary concentrating ability was significantly improved in TMZ-preserved groups compared with TMZ-free groups. In TMZ-supplemented groups, there was also a greater excretion of citrate, which is a citric acid cycle metabolite. An extensive reduction in apical brush border of tubular cells, notably those of the proximal tubules, was noted in TMZ-free groups. This study clearly shows that TMZ has a beneficial action on in vivo renal preservation and its major impact is the vulnerable renal medulla.

Animals↗
PubMed2000

Broad spectrum antimicrobial activity of a new multi-purpose disinfecting solution.

PURPOSE: There has been increasing awareness of the need for more powerful contact lens disinfectants, ideally having low toxicity and allergenicity to ocular tissue. Opti-Free Express with ALDOX Multi-Purpose Disinfecting Solution (MPDS) was recently marketed as a new multi-purpose disinfecting solution for soft contact lenses. MPDS contains two antimicrobial agents, polyquaternium-1 and myristamidopropyl dimethylamine, to broaden the range of antimicrobial activity. The purpose of this study was to evaluate the antimicrobial activity of MPDS against microorganisms that have been reported as contact lens and lens case contaminants and causative agents of microbial keratitis. METHODS: MPDS was challenged with high numbers of gram-positive and gram-negative bacteria, yeast, mold, and Acanthamoeba. Several lots of product were challenged with at least three separate inocula of each isolate. After exposure to the disinfecting solution, a sample was removed from the product and plated for survivors by suitable recovery methods. The plates were incubated and the number of survivors was enumerated. RESULTS: The results showed that MPDS was bactericidal, fungicidal and amoebicidal against an extensive variety of environmental contaminants of lens care accessories and ocular pathogens. MPDS was capable of killing a broad spectrum of microorganisms. The log reduction exceeded the primary criteria for disinfecting products and produced a notable reduction of other clinical and environmental isolates as well. CONCLUSIONS: Opti-Free Express MPDS contains antimicrobial agents that can kill an extensive spectrum of many different types of microorganisms that may contaminate contact lenses and solutions.

Acanthamoeba↗
PubMed2000

The dipyridamole effect on the photoactive bacteriochlorophyll interaction with quinone acceptors in reaction centers of purple bacteria.

The effect of Dipyridamole (10(-6)-10(-3) M) on the photomobilized electron transport in the system of quinone acceptors Q(A)-Q(B) of isolated photosynthetic reaction centers of Rhodobacter sphaeroides and on its temporary stabilization on Q(B) was studied. Depending on the type of the detergent present in the reaction center (lauryl dimethylamine oxide, Triton X-100, sodium dodecyl sulfate, and sodium cholate), dipyridamole could increase the time of the electron transfer to Q(B). The dipyridamole effect on the efficiency of the electron stabilization on Q(B) for reaction centers with different detergents was revealed in slowing down the process of dark reduction of photoactive bacteriochlorophyll from Q(B) at initial concentrations of added dipyridamole (10(-6)-10(-5) M) with following acceleration of the process at the dipyridamole concentrations of 10(-4)-10(-3) M. The pH lowering from 6.8-7.0 to 5.9-6.0 increased the dipyridamole effect. The possibility of the dipyridamole effect on the structural-dynamic state of the reaction center complex, including its hydrogen bond system, which influences the studied parameters of functional activity, is suggested.

Bacteriochlorophylls↗
PubMed2000

[Some etiologic factors in condom-induced allergic contact balanitis].

Clinical cases presenting allergic contact balanitis from condoms are studied using a combination of patch testing and chemical analysis by gas chromatography and high-resolving liquid chromatography to identify the causative agents involved. It has been previously established that zinc ethylphenyl dithiocarbamate (ZEPC)--a dithiocarbamate-type accelerant (DTC)--is an etiological factor in the event of contact allergy to condoms. Later it is confirmed that DTCs, such as zinc dimethyl dithiocarbamate (ZDMC), zinc diethyl dithiocarbamate (ZDEC) and zinc dibutyl dithiocarbamate and amines, such as dimethylamine (DMA), diethylamine (DEA) and piperidine (PIP) are likewise implicated in condom-induced contact balanitis. As shown by the investigation along this line, although thiurams are believed to be more allergenic, as compared to the corresponding DTCs and amines, both DTCs (ZDMC, ZDEC, ZDBC, ZEPC) and amines (DMA, DEA and PIP) are noteworthy etiological factors of allergic contact balanitis from condoms.

Adult↗
PubMed2001

X-ray diffraction and neutron scattering studies of amphiphile-lipid bilayer organization.

The lipid bilayer thickness d(L), the transbilayer distance of lipid phosphate groups d(pp/inf> and the lipid surface area A(L) of fluid hydrated bilayers of lamellar phases of egg phosphatidylcholine or dipalmitoylphosphatidylcholine containing N-alkyl-N,N-dimethylamine N-oxides (CnNO), 1,4-butanedi-ammonium-N,N'-dialkyl-N,N,N',N'-tetramethyl dibromides (GSn) or mono-hydrochlorides of [2-(alkyloxy)phenyl]-2-(1-piperidinyl)ethylesters of carbamic acid (CnA) were obtained by X-ray diffraction, and the bilayer thickness in extruded unilamellar dioleoylphosphatidylcholine vesicles containing C12NO was obtained by the neutron scattering. The values of d(L), d(pp/inf> and A(L) change linearly up to the 1:1 amphiphile:lipid molar ratio. The slopes of these dependencies increase for d(L) and d(pp/inf> and decrease for AL) with an increasing number of carbons n in the amphiphile long hydrocarbon substituent (18> or =n> or =8 for CnNO, 16> or =n> or =9 for GSn, 12> or =n> or =5 for CnA), while the opposite trends are observed for the short substituent (8> or =n>/=6 for CnNO, 9> or =n> or =7 for GSn, 5> or =n> or =3 for CnA). In case of long substituents, the effects on dL), dpp/inf> and AL) are caused by the decrease in the difference between the lipid and amphiphile hydrocarbon chain lengths and by the increase in their van der Waals attraction. The short substituent amphiphiles are mobile and exchange between multiple binding sites in the bilayer, minimizing the bilayer surface area.

1,2-Dipalmitoylphosphatidylcholine↗
PubMedDate not supplied

Real-time, high-resolution quantitative measurement of multiple soil gas emissions: selected ion flow tube mass spectrometry.

A new technique is presented for the rapid, high-resolution identification and quantification of multiple trace gases above soils, at concentrations down to 0.01 microL L(-1) (10 ppb). The technique, selected ion flow tube mass spectrometry (SIFT-MS), utilizes chemical ionization reagent ions that react with trace gases but not with the major air components (N2, O2, Ar, CO2). This allows the real-time measurement of multiple trace gases without the need for preconcentration, trapping, or chromatographic separation. The technique is demonstrated by monitoring the emission of ammonia and nitric oxide, and the search for volatile organics, above containerized soil samples treated with synthetic cattle urine. In this model system, NH3 emissions peaked after 24 h at 2000 nmol m(-2) s(-1) and integrated to approximately 7% of the urea N applied, while NO emissions peaked about 25 d after urine addition at approximately 140 nmol m(-2) s(-1) and integrated to approximately 10% of the applied urea N. The monitoring of organics along with NH3 and NO was demonstrated in soils treated with synthetic urine, pyridine, and dimethylamine. No emission of volatile nitrogen organics from the urine treatments was observed at levels >0.01% of the applied nitrogen. The SIFT method allows the simultaneous in situ measurement of multiple gas components with a high spatial resolution of < 10 cm and time resolution <20 s. These capabilities allow, for example, identification of emission hotspots, and measurement of localized and rapid variations above agricultural and contaminated soils, as well as integrated emissions over longer periods.

Agriculture↗
PubMed2002

A kinetic model of N-nitrosodimethylamine (NDMA) formation during water chlorination/chloramination.

Experiments were conducted to investigate the hypothesis that N-nitrosodimethylamine (NDMA) is a potential disinfection by-product. NDMA was formed by the reaction of dimethylamine (DMA) with monochloramine and also with free chlorine in the presence of ammonia. We proposed a mechanism for NDMA formation which does not require the presence of nitrite as in N-nitrosation. The critical NDMA formation reactions consist of i) the formation of monochloramine by combination of free chlorine with ammonia, ii) the formation of 1,1-dimethylhydrazine (UDMH) intermediate from the reaction of DMA with monochloramine followed by, iii) the oxidation of UDMH by monochloramine to NDMA, and iv) the reversible chlorine transfer reaction between free chlorine/monochloramine and DMA which is parallel with i) and ii). A kinetic model was developed to validate the proposed mechanism.

Carcinogens↗
PubMed1990

Synthesis and antimicrobial activity of 2'-deoxypuromycin.

2'-Deoxypuromycin (2) was synthesized to learn the effect of the 2'-hydroxyl group on the biological activity. Acylated xylose 3 was condensed with silylated 6-chloropurine to give beta-D-xylofuranosyl-6-chloropurine derivative 4, whose 6-dimethylamination, 2'-deoxygenation and deprotection afforded 2'-deoxy-beta-D-xylofuranosyl purine analog 7. The latter was converted to 2'-deoxypuromycin (2) in 8 steps. 2'-Deoxy analog 2 showed only weak antimicrobial activity compared with that of puromycin (1).

Anti-Bacterial Agents↗
PubMed1992

Nuclear magnetic resonance spectroscopy and pattern recognition analysis of the biochemical processes associated with the progression of and recovery from nephrotoxic lesions in the rat induced by mercury(II) chloride and 2-bromoethanamine.

Nephrotoxic lesions were induced in Fischer 344 rats using HgCl2, a proximal tubular toxin, and 2-bromoethanamine (BEA), a medullary toxin. Biochemical effects of these toxins on urinary composition were observed by high resolution 1H NMR spectroscopy over 9 days after dosing. The onset of, progression of, and recovery from the induced toxic lesions were also followed histopathologically and related to the perturbed urinary biochemistry. Urinary concentrations of 20 endogenous substances were measured simultaneously by NMR at eight time points, to provide a time-related 20-dimensional description of the urinary biochemistry for each rat. Principal components analysis and nonlinear mapping were used to reduce the biochemical parameter spaces for each rat to two or three dimensions for display and classification purposes. An investigation of alternative data-presentation methods was made, and taking interanimal means of the map coordinates at each time point yielded a novel type of metabolic trajectory diagram with which the biochemical abnormalities associated with the HgCl2 and BEA lesions could be related to the progression and recovery phases of the toxic lesions. The time-course trajectories showed characteristically different paths for each toxin. These trajectories allowed the time points at which there were maximum metabolic differences to be determined and provided the visualization of net movements of the treatment group populations in time in relation to interanimal variation. Control animal urine samples subjected to this analysis showed simple clustering, with no evidence of metabolic trajectory. The trajectory for BEA showed different routes for onset of and recovery from toxicity, whereas for HgCl2 the outward trajectory (onset) mapped a space similar to the inward trajectory (recovery phase). This suggests that the NMR-detectable biochemical abnormalities after mercury toxicity mainly reflect the proportions of functional cells lining the nephron, whereas the biochemical abnormalities associated with renal medullary insult probably relate to functional integrity. An examination has been made for those metabolites that are most responsible for defining the trajectories, i.e., the discrimination of renal cortical and medullary toxicity from each other and from controls. These discriminatory metabolites (using paired t test, p < 0.001) included valine, taurine, trimethylamine N-oxide, and glucose for HgCl2 and acetate, methylamine, dimethylamine, lactate, and creatine for BEA, whereas citrate, succinate, N-acetyl resonances from as yet unidentified metabolites, hippurate, alanine, and 2-oxoglutarate played an important role in defining the biochemically perturbed trajectory of both toxins.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2002

[The activity of blood cholinesterase in rats exposed to dimehypo].

OBJECTIVE: To determine whether and to what degree the activity of cholinesterase(ChE) is inhibited by dimehypo at different doses of dimehypo [scientific name: 2-dimethylamine-1,3-bi(sodium hyposulfit)]. METHOD: Rats were dosed with dimehypo or methamidophos orally, and were randomly divided into four subgroups according to the pesticide doses, which were 1/16, 1/8, 1/4 and 1/2 of LD50 respectively(the LD50 of dimethypo and methamidophos is 342 mg/kg and 20 mg/kg respectively). The activity of ChE in blood was determined before and 30 min, 1, 2, 4 and 24 h after exposure. The modified Ellman Method was employed to measure the activity of ChE. RESULT: 1/16 LD50 dose of dimehypo did not affect the activity of ChE. When the dose increased, the activity of ChE decreased accordingly. 1/2 LD50 dose of dimehypo inhibited the activity of ChE by 35.9% compared with that of control group(P < 0.01). In rats dosed with methamidophos, even 1/16 LD50 dose inhibited the activity of ChE by 42.4% compared with that of control group. When the dose of methamidophos increased, the activity of ChE decreased accordingly. 1/2 LD50 dose of methamidophos inhibited the activity of ChE by 52.9%. The activity of ChE in the rats dosed with dimehypo at various doses was significantly lower than that in the rats dosed with corresponding doses of methamidophos(P < 0.01). CONCLUSION: Higher doses of dimehypo may inhibit the activity of ChE. However, as compared with methamidophos, dimehypo is a weaker inhibitor of ChE.

Animals↗
PubMed2004

Analysis of sulfur and nitrogen odorants using solid-phase microextraction and GC-MS.

An analytical method involving solid-phase micro-extraction (SPME) and gas chromatography-mass spectrometry (GC-MS) was applied to analyze biosolids odors. A selective ion monitoring (SIM)-based MS method was developed, using SPME injections of odorant standards under the full-scan mode to select the quantification and confirmation ions for each odorant. The odorants analyzed in this study include: dimethylsulfide, dimethyldisulfide, methyl mercaptan, hydrogen sulfide, carbon disulfide, trimethylamine and dimethylamine. We have used this method to quantify parts-per-billion levels of odorant vapors produced during anaerobic incubation of digested wastewater sludge. Important considerations for expedient and accurate calibration under static and dynamic flow conditions are discussed. The SPME-GC-MS method may give a positive intercept in the calibration curve, especially under static sampling conditions, which sets a practical detection limit for odor analysis.

Chemistry Techniques, Analytical↗