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PubMed1981

Experiences using chloramine-T and 1, 3, 4, 6-tetrachloro-3 alpha, 6 alpha-diphenylglycoluril (Iodogen) for radioiodination of materials for radioimmunoassay.

A comparison of labelling compounds with chloramine-T and with 1, 3, 4, 6-tetrachloro-3 alpha, 6 alpha-diphenylglycoluril (Iodogen) has been carried out. For human transferrin, human calcitonin, 1-84 bovine parathyrin, fibrinopeptide-A, human thyrotropin and F-CB3, a cyanogen bromide cleavage peptide of human fibrinogen, the quality of tracer produced by the Iodogen method was better. For rat lutropin, human growth hormone and human prolactin, labelling with Iodogen produced a tracer of unsatisfactory quality. For a further 13 peptides, the results from both methods were comparable. Optimal reaction times using Iodogen were of the magnitude of two to three times longer than when using chloramine-T. Reduction of the volume of radioactive waste by up to 90% could be achieved when the Iodogen method was coupled with a short cation-exchange column to separate unreacted iodide from the labelled compound. Data is presented on the quality of tracer, expressed in terms of elution profiles and radioimmunoassay standard curves. A novel "combi-method" of labelling proteins without tyrosine or histidine moieties is presented where N-succinimidyl-3-(4-hydroxyphenyl)-propionate is labelled at pH 7.5 using Iodogen to give "Bolton-Hunter" reagent, which is then transferred to a vessel containing the peptide to be labelled at ph 8.6.

Animals↗
PubMed1977

Physiologic and biologic behavior of autologous canine 131L-fibrinogen labeled by a chloramine-T method.

Autologous canine 131I-fibrinogen labeled by a chloramine-T method was examined to determine whether the fibrinogen had been altered by the iodination procedure as suggested by other investigators. Before and after radioiodination, clottability of the fibrinogen was always equal to or greater than 89 percent. Gel chromatography studies revealed that labeled fibrinogen behaved as unlabeled fibrinogen and no high molecular weight material was found. Gamma camera scintigraphy reflected the chromatography results, as iodinated material did not appear in the liver or spleen until 48 to 72 hours. The slow-moving component of the whole blood clearance curves, respresenting undenatured fibrinogen, had a mean half-life of 61.4 +/- 5.1 hours (+/- S.E.M.) and comprised 51.5 +/- 7.5 percent of the initial activity. Similarly, a mean falf-life of 53.4 +/- 2.0 hours and 59.6 +/- 7.7 percent initial activity wwere attributed to fibrinogen according to the plasma clearance curves as determined by trichloracetic acid precipitation. The results clearly demonstrated that chloramine-T iodination of fibrinogen can yield an excellent product, biologically and chemically, which is free from macroaggregates.

Animals↗
PubMed1996

Effects of formalin, chloramine-T, and low salinity dip on the behavior and hemolymph biochemistry of the American lobster.

The purpose of this research was to investigate the salinity and formalin sensitivity of a ciliate parasite (Anophryoides haemophila) of the American lobster (Homarus americanus), and to examine the target-animal (lobster) safety of chemical-bath treatments involving low salinity, formalin, or chloramine-T that could be used to control this parasite in lobster pounds. "Bumper car" disease, caused by An. haemophila, is an important concern to lobster pound operators in eastern North America, because of the implicated lobster mortality rate and the general lack of preventive and therapeutic intervention regimes. We determined, using an in vitro method, that formalin at 50 mg/L, or low salinity at 8.0 parts per thousand (ppt) for 1 hour killed 100% of the parasites. When healthy lobsters were exposed to formalin at 200 mg/L, there were no negative behavioral responses and no significant differences in a panel of hemolymph biochemical indices. Similar results occurred when lobsters were exposed to chloramine-T, a common finfish therapeutic agent for topical bacteria and protozoa, at 10 mg/L for 1 hour. The low salinity treatment (8.0 ppt) resulted in significant adverse changes in lobster behavior and biochemical indices; however, these changes did not persist for more than 1 week after treatment ended. Although these treatments are unlikely to kill parasites that have already invaded the lobster carapace, they should be effective in reducing parasite loads on the gill and carapace surface of the lobster and in the environment of the impoundment housing.

Animals↗
PubMedDate not supplied

Chemiluminescence of ABEI-labelled IgG triggered by the N-chloramine-H(2)O(2)-p-iodophenol system.

Light is emitted in systems containing N-chloramines or hypochlorite, H(2)O(2) and N-(4-aminobutyl)-N-ethylisoluminol (ABEI). The emission is enhanced by 4-iodophenol (PIP) in alkaline solution (1 mol/L NaOH), while at lower pH range (9-11) PIP is not only inactive but also its presence reduces chemiluminescence (CL) of the monochloramine-H(2)O(2)-ABEI system to the background. Two procedures for ABEI-labelled IgG assays were developed, with PIP in 1 mol/L NaOH and without PIP at pH 11, and the standard curves of free ABEI in these conditions were examined. We suggest also that the oxidative deamination of taurine chloramine leads to the formation of the various carbonyl derivatives and their formation is accelerated in the presence of H(2)O(2), especially in less alkaline solutions (pH 11). Moreover, the formation of enol forms of aldehydes in assay buffers was observed. The yield of the phenoxy radical mediators of ABEI oxidation and the pH-dependent H(2)O(2):HO(2) ratio seems to be decisive for the overall CL in the system examined. The main advantage of this method is that CL does not need precise timing of measurements and assays can be performed over a long period of time (hours) using a plate luminometer.

Aldehydes↗
PubMed1995

Taurine chloramine, a product of activated neutrophils, inhibits in vitro the generation of nitric oxide and other macrophage inflammatory mediators.

Taurine (Tau) is an exceptionally abundant free amino acid in the cytosol of inflammatory cells and especially in neutrophils. Taurine protects cells from self-destruction during processes that generate oxidants. The major function of Tau in leukocytes is to trap chlorinated oxidants (HOCl). Taurine reacts with HOCl to produce the long-lived compound taurine chloramine (TauCl). Previously, we have shown that other products of the neutrophil chlorinating system are able to modify functions of macrophages. In this study, we investigated in vitro the influence of TauCl on the generation of inflammatory mediators by activated macrophages. We have found that TauCl inhibited the generation of nitric oxide, prostaglandin E2, tumor necrosis factor alpha, and interleukin-6, but TauCl slightly enhanced the release of IL-1 alpha. The formation of nitrites by interferon-gamma-activated macrophages was inhibited by TauCl in a dose-dependent manner. Taurine chloramine also reduced the level of inducible nitric oxide synthase (iNOS) mRNA in macrophages, in a similar concentration-dependent manner. Although our experiments do not exclude a direct effect of TauCl on enzymatic activity of iNOS, the inhibition of iNOS expression seems to be the major mechanism responsible for suppression of NO formation. Finally, we discuss the biological role of TauCl in vivo. We suggest that at the site of inflammation TauCl works as a specific signaling molecule of activated neutrophils that coordinates the generation of inflammatory mediators in macrophages.

Animals↗
PubMed2001

Organic chloramine analysis and free chlorine quantification by electrospray and atmospheric pressure chemical ionization tandem mass spectrometry.

Atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), together with tandem mass spectrometry (MSn), are used to study the mechanism of chlorination of amines and to develop a method for qualitative and quantitative determination of organic chloramines. Cyclohexylamine and 1,4-butanediamine (putrescine) are used as model compounds to investigate the mechanisms of the reactions between primary aliphatic amines and hypochlorous acid (aqueous Cl2). The chlorination products are identified and characterized by collision-induced dissociation (CID) and H/D exchange. Chlorination occurs by electrophilic addition of Cl+ and may be followed by HCl elimination, hydrolysis, or, in the case of diamines, amine elimination by intramolecular nucleophilic substitution. The relative rates of chlorination at amine and chloramine nitrogens are a function of pH and depend on the basicity of the amine. A novel method for active chlorine quantification using ESI or APCI mass spectrometry is suggested on the basis of the extent of chlorination of a sacrifical amine standard. This measurement has a limit of detection for N-chlorocyclohexylamine in the range of 0.1-10 microM, a linear dynamic range of 10(2)-10(3), and an accuracy of +/-10%, as determined for wastewater samples.

Journal Article↗
PubMed2003

Unusual reaction of chloramine-T with araldoximes.

Reaction of araldoximes with 4 equiv of chloramine-T in refluxing methanol produces N-(p-tolyl)-N-(p-tosyl)benzamides via addition of 2 equiv of chloramine-T to the intermediate nitrile oxide followed by extrusion of sulfur dioxide.

Journal Article↗
PubMed2004

Taurine and its chloramine: modulators of immunity.

Taurine is a semiessential amino acid that is not incorporated into proteins. In mammalian tissues, taurine is ubiquitous and is the most abundant free amino acid in the heart, retina, skeletal muscle, and leukocytes. Taurine reaches up to 50 mM concentration in leukocytes. Taurine has been shown to be tissue-protective in many models of oxidant-induced injury. One possibility is that taurine reacts with HOCl, produced by the myeloperoxidase (MPO) pathway, to produce the more stable but less toxic taurine chloramine (Tau-Cl). However, data from several laboratories demonstrate that Tau-Cl is a powerful regulator of the immune system. Specifically, Tau-Cl has been shown to downregulate the production of proinflammatory mediators in both rodent and human leukocytes. Recent molecular studies on the function of taurine provide evidence that taurine is a constituent of biological macromolecules. Specifically, two novel taurine-containing modified uridines have been found in both human and bovine mitrochondria. In studies on mechanism of action, Tau-Cl inhibits the activation of NFkappaB, a potent signal transducer for inflammatory cytokines, by oxidation of IkappaB alpha at methionine45. Taurine transporter knockout mice show reduced taurine, reduced fertility, and loss of vision resulting from severe retinal degeneration, which was found to be due to apoptosis. Apoptosis induced by amino chloramines is a current and important finding because oxidants derived from leukocytes play a key role in killing pathogens. The fundamental importance of taurine in adaptive and acquired immunity will be revealed using genetic manipulation.

Animals↗
PubMed1999

Regulation of murine dendritic cell functions in vitro by taurine chloramine, a major product of the neutrophil myeloperoxidase-halide system.

Taurine chloramine (TauCl) is a major chloramine generated in activated neutrophils as a result of the reaction of highly toxic hypochlorous acid and taurine, the most abundant free amino acid in cytosol. In this study we have tested the influence of TauCl on the properties of murine dendritic cells (DC), the major cell population involved in the initiation of an adaptive immune response against pathogenic organisms. N418+, MHC II+, B7-2+ dendritic cells, generated from the mouse bone marrow cells cultured in the presence of granulocyte-macrophage colony-stimulating factor, were stimulated by interferon-gamma and lipopolysaccharide to produce nitric oxide, reactive oxygen species, interleukin-6 (IL-6), tumour necrosis factor-alpha, and IL-12, in the presence of different doses of TauCl. TauCl differently inhibited the generation of these inflammatory mediators in a dose-dependent manner. Furthermore, TauCl selectively modulated the ability of DC to induce the release IL-2 and IL-10 from T cells. These results suggest that neutrophil-derived mediators, such as TauCl, at a site of inflammation, may affect the functions of sentinel DC and macrophages, and play a role in maintaining the balance between the inflammatory response and the induction of an antigen-specific immune response.

Animals↗
PubMed1992

[Aqueous chloramine T solutions as disinfectants: chemical composition, reactivity and toxicity].

In aqueous solutions of Chloramine T (CAT), caused by dissociation, hydrolysis and disproportionation processes, seven different kinds of molecules emerge (HOCl, OCl-, R-NCl-, R-NHCl, R-NCl2, R-NH2, and R-NH- [R = CH3-C6H4-SO2]). Their equilibrium concentrations have been calculated using an iteration process (polynom of 4th degree) as a function of cCAT (0.003-10%) and pH (0-14): The (absol.) concentration of "free chlorine" ([HOCl] + [OCl-]) is surprisingly low showing a maximum concentration of HOCl in the whole concentration and pH range of only 2 . 10(-7) moles/l (0.014 ppm). The relative equilibrium concentrations of the N-chlorinated toluene sulfonamide species R-NCl-, R-NHCl, and R-NCl2, virtually alone responsible for the oxidizing and by this also disinfecting properties, owing to the extremely low concentration of free chlorine, are influenced in the concentration range relevant for practice (greater than 0.1%) only by the pH-value: At pH greater than 7 the whole oxidation capacity is present as R-NCl- (pH 7: 99.6%; pH 8: 99.96%), while at pH less than 3 it is formed by R-NHCl and R-NCl2.(ABSTRACT TRUNCATED AT 250 WORDS)

Chloramines↗
PubMed2004

A novel spectrophotometric determination of some phenothiazines involving iodine monochloride from chloramine-T with iodine.

A novel, simple, sensitive spectrophotometric method is proposed for the determination of five phenothiazines. Chloramine-T with iodine in acetic acid produces iodine monochloride which oxidizes phenothiazines to absorbing cations. Those would associate later with unreacted ICl to form an ion pair, [Ph+] [ICl-(2)] in hydrochloric acid medium. These appear to provide exceptional color stability to the systems. A probable mechanism along with experimental stoichiometry and stability constants of such ion pairs is indicated. The method is not only successful in stabilizing the color of the systems, but also in making a unique observation of two regions of concentration of phenothiazines adhering separately to Beer's law. The results obtained from the analyses of pure samples and their drug formulations in both regions of concentration are comparable with those obtained either with a reported titrimetric method or with a British Pharmacopoeia (B.P.) UV-spectrophotometric method. The conditions required for the quantitative determination of phenothiazines are described and related analytical parameters are also calculated.

Chloramines↗
PubMed1995

Mutation spectra in salmonella of chlorinated, chloraminated, or ozonated drinking water extracts: comparison to MX.

Drinking water samples were prepared in a pilot-scale treatment plant by chlorination (Cl2), chloramination (NH2Cl), ozonation (O3), or O3 followed by Cl2 or NH2Cl; and the nonvolatile acidic organics of the raw and treated waters were extracted by XAD/ethyl acetate and evaluated for mutagenicity in Salmonella (-S9). The extracts were 2-8 times more mutagenic in TA100 than in TA98, and the mutagenic potencies of the water extracts ranked similarly in both strains: Cl2 > O3 + Cl2 > NH2Cl > O3 + NH2Cl > O3 > raw. 3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), which was estimated to account for approximately 20% of the mutagenic activity of the extracts, was shown to be the most potent compound tested thus far in a prophage-induction assay in Escherichia coli and a forward-mutation assay in Salmonella TM677. The mutations in approximately 2,000 revertants of TA98 and TA100 induced by MX and the water extracts were analyzed by colony probe hybridization and polymerase chain reaction/DNA sequence analysis. The water extracts and MX produced similar mutation spectra, which consisted in TA100 of predominantly of GC-->TA transversions in the second position of the CCC (or GGG) target of the hisG46 allele. This spectrum resembles that produced by large aromatic compounds and is distinct from that produced by alkylating agents and the semivolatile drinking water mutagen dichloroacetic acid. In TA98, MX and those water extracts resulting from the introduction of the chlorine atom produced 50-70% hotspot 2-base deletions and 30-50% complex frameshifts (frameshifts with an adjacent base substitution--mostly GC-->TA transversions as found in TA100). No other compound or mixture is known to induce such high frequencies of complex frameshifts. These results suggest that MX and "MX-like" compounds (possibly halogenated aromatics, such as halogenated polycyclic aromatic hydrocarbons) account for much of the mutagenic activity and specificity of the nonvolatile organics in drinking water and that these halogenated organics are especially capable of promoting misincorporation by the DNA replication complex. This study provides further evidence that the mutation spectrum of a complex mixture reflects the dominance of one or a few classes of chemical mutagens within the mixture.

Alleles↗
PubMed1976

N-Halo derivatives V: Comparative antimicrobial activity of soft N-chloramine systems.

Comparative antimicrobial activity studies for certain new classes of soft N-chloramines derived from alpha-aminiisobutyric acid and 2-amino-2-methyl-1-propanol were examined using the minimum inhibitory concentration (MIC) and/or the contact germicidal efficiency (CGE) procedures. Several factors significantly aliphatic chain length in a homologous series, (b) the degree of chlorination of thenitrogen atom, (c) the solution pH, (d) the presence of a denaturant, and (e) the nature of a positive charge.

Anti-Infective Agents↗
PubMed1992

Structure-activity considerations in kinetics and mechanism of chlorine exchange between chloramine-T and secondary amines.

To study the mechanism of N-chlorination of secondary amines by chloramine-T, the kinetics of the reactions of some aromatic-substituted analogues of N-chlorobenzenesulfonamide with various secondary amines were determined. The importance of amine basicity and reactivity of the N-Cl bond of the N-chlorobenzenesulfonamide was also assessed. The results indicate that a mechanism involving the un-ionized species of both reactants (i.e., a molecular mechanism), rather than an ionic mechanism, is operating and that the reaction most likely proceeds via a six-membered-ring transition state that incorporates a water molecule.

Algorithms↗
PubMed2001

External interface for trap-and-release membrane introduction mass spectrometry applied to the detection of inorganic chloramines and chlorobenzenes in water.

Construction and evaluation of an external configuration trap-and-release membrane introduction system for mass spectrometry is described. This novel interface allows independent control of the temperature of the membrane and eliminates the dependence of membrane heating efficiency on its position in the ion source. The external trap-and-release MIMS configuration is successfully applied to detection of inorganic chloramines and chlorobenzenes. The method is shown to give temporal resolution of volatile vs. semi-volatile compounds, which increases its sensitivity for semi-volatiles in the presence of volatiles and provides an additional selectivity parameter. Further selectivity is provided by tandem mass spectrometry.

Chloramines↗
PubMed1995

Chloramine-T in radiolabeling techniques. II. A nondestructive method for radiolabeling biomolecules by halogenation.

Chloramine-T (CAT) is commonly used in the radiolabeling of bioactive molecules by halogenation. CAT may be used either as a solution or in an immobilized form (Iodobeads) to release radioactive elemental iodine or other halogens by oxidation of their salts. CAT has a very high chlorine potential, and it causes oxidative damage to sensitive substrate molecules, such as peptides and proteins. In some cases, the substrates are completely destroyed. To reduce the chlorine potential of CAT, morpholine was mixed with CAT prior to exposure to the substrates. This formed N-chloromorpholine, in situ, which readily reacted with KI to form I2. The kinetics of the formation of N-chloromorpholine from CAT and morpholine were studied spectrophotometrically by following the disappearance of CAT at 250 nm. The reaction was found to be rapid at all pH's from 5 to 11. 1-Aminocyclohexanecarboxylic acid (a model amino acid) decomposed rapidly in the presence of CAT, but there was no decomposition in the presence of N-chloromorpholine. N-Chloromorpholine was compared to CAT solution and Iodobeads for the iodination of L-tyrosine. The formation of mono- and diiodotyrosine were followed by HPLC. On an equimolar basis (0.55 microM), N-chloromorpholine produced a much greater yield of the mono- and diiodinated tyrosine than Iodobeads. Furthermore, decomposition products were observed when tyrosine was exposed to Iodobeads for 15 min. When a CAT solution was used at a higher concentration (5.5 microM), a substantial amount of decomposition occurred, and the yields of the two iodinated species were very small.(ABSTRACT TRUNCATED AT 250 WORDS)

Chloramines↗
PubMed2006

Anti-inflammatory effects of taurine derivatives (taurine chloramine, taurine bromamine, and taurolidine) are mediated by different mechanisms.

In this study, in an animal model of zymosan-induced peritonitis we have tested anti-inflammatory properties of Taurolidine (TRD), a synthetic derivative of taurine. In vitro, the effect of TRD and HOCl treated TRD on peritoneal macrophages was compared with that of TauCl. We report that locally administered TRD (Taurolin) shows strong anti-inflammatory properties. TRD inhibits vascular permeability increased by inflammatory stimuli; it also significantly attenuates the influx of neutrophils into the peritoneal cavity, as well as the production of pro-inflammatory cytokines (TNF-alpha, IL-6) by peritoneal exudate cells. Chlorination of TRD resulted in the formation of chloramine (TRD-Cl), as confirmed by characteristic UV spectra. Both TRD and TRD-Cl, more effectively than TauCl, inhibited the production of IL-6 by stimulated macrophages. The effect was not dependent on its well-known anti-endotoxin activity since TRD inhibited cytokine production by macrophages stimulated with either LPS or IFN-gamma. Finally, we report that anti-inflammatory activities of TRD and taurine haloamines are mediated by different mechanisms. TRD, in contrast to TauCl and TauBr, does not induce expression of HO-1, a stress inducible enzyme with strong anti-inflammatory properties.

Animals↗
PubMed1987

Subconductance states of single sodium channels modified by chloramine-T and sea anemone toxin in neuroblastoma cells.

Single channel currents of chloramine-T (Chl-T) and sea anemone toxin (ATX-II) modified sodium channels were studied in neuroblastoma cells. With both substances similar subconductance states have been observed. The conductances of the sublevels were multiples of the "unit" step which was about one-forth of the most frequently occurring main conductance. Thus, the current levels observed were one fourth, half and five-fourths of the main current size. Both substances caused a slower decay of the averaged current compared to the current of the native channels. The main single-channel conductance was 15.2 pS (T = 16 degrees C) for the Chl-T and 10.8 pS (T = 12 degrees C) for the ATX-II modified channels. The channel open time was doubled by ATX-II, but was not increased significantly by Chl-T. The existence of the subconductance states suggests that the native channels may also have multiple open conformations.

Animals↗