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PubMed1984

Ceruloplasmin. Increased serum concentration and impaired antioxidant activity in cigarette smokers, and ability to prevent suppression of elastase inhibitory capacity of alpha 1-proteinase inhibitor.

Bronchoalveolar lavage fluid of smokers and nonsmokers contains significant concentrations of ceruloplasmin, the major serum inhibitor of lipid peroxidation, with limited superoxide dismutase activity. This suggested that ceruloplasmin may protect the lower respiratory tract against oxidant(s) in cigarette smoke and air pollutants. We investigated (1) serum ceruloplasmin concentration and antioxidant activity (percentage inhibition of autoxidation of ox-brain homogenate) in healthy male and female smokers and nonsmokers, and (2) the capacity of ceruloplasmin to prevent suppression of the elastase inhibitory capacity of alpha 1-proteinase inhibitor by the oxidant chloramine T and by cigarette smoke solution. Mean ceruloplasmin concentration was 18% higher in 35 female smokers than in 46 male smokers (p less than 0.001), 17% higher in 22 female nonsmokers than in 18 male nonsmokers (p less than 0.005), 15% higher in the female smokers than in the female nonsmokers (0.02 greater than p greater than 0.01), and 14% higher in the male smokers than in the male nonsmokers (p less than 0.001). Serum antioxidant activity showed significant linear correlations with serum ceruloplasmin in smokers and nonsmokers of both sexes; correlation coefficients, all significant, ranged from 0.65 to 0.50. For comparable ceruloplasmin concentrations, serum antioxidant activity was significantly lower in smokers (males: 9%, p less than 0.001; females: 7%, 0.05 greater than p greater than 0.01) than in nonsmokers. There was a linear relationship between ceruloplasmin concentration and its ability to prevent suppression of the elastase inhibitory capacity of alpha 1-proteinase inhibitor by chloramine T and cigarette smoke solution. Our findings indicate: (1) that cigarette smoking can cause partial inactivation of serum antioxidant activity accompanied by insufficient compensatory increase in ceruloplasmin concentration, and (2) that ceruloplasmin may protect the lung against oxidant(s) in cigarette smoke and air pollutants.

Adult↗

PubMed1983

Laboratory investigations on the effect of selected disinfectants on survival of the cockroaches Blattella germanica (L.).

It was ascertained that lysol 2% and 5% showed the most toxic effect in control of cockroaches in the contact method (23.3% and 95.5% mortality after 24 hours of exposure), and that chloramine 1%, 3% and 5% was the most effective food poison (after 19 days exposure 100% of the insects died). When injecting disinfectant into the body cavity, the cockroaches showed a ten times higher sensibility to formalin and chloramine than to lysol. The use, however, of disinfectant in the contact method (particularly lysol 2%) together with an insecticide based on propoxur, allowed to reduce its dose to a half, what gave better results than the use of an insecticide alone in a normal dose.

Animals↗

PubMed1982

[Gastrin radioimmunoassay with polyethylene glycol method].

125I-labelled gastrin with high immunological activity and high specific radioactivity of 22.2 approximately 25.9 GBq (600 approximately mCi)/mg (0.5 iodine atom/1 gastrin molecule) was prepared by chloramine-T method using the amount of 100 molar ratio of chloramine-T to gastrin. As results of gastrin radioimmunoassay with polyethylene glycol (PEG) method, intra- and interassay coefficient of variation (C.V.) were 3.6 approximately 7.6% and 5.7 approximately 10.4%, respectively. The average recoveries of 2 levels of gastrin added to serum samples were 104 +/- 11.9% and 105 +/- 9.7%. The correlation coefficient of gastrin values obtained with dextrancoated charcoal (DCC) method and present method was r = 0.973. Antibody used in this study have a characteristic to strongly recognize the tyrosin residue at 12 position and the methionyl residue at 15 position on gastrin (1-17).

Antibody Specificity↗

PubMedDate not supplied

Investigations concerning the action of serveral chemical and biological agents on HBsAg.

Native and purified HBsAg preparations were subjected in vitro to the action of cetylpyridinium bromide (Bromocet), hibitan-chlorhexidine (Hibiscrub), chloramine B and propolis extract, at different concentrations and for various time intervals. The effect of these agents on the serological reactivity of HBsAg was tested by electroimmunodiffusion (EID) and radioimmunoassay (RIA). Chloramine B and the propolis extract had a significant inhibitory effect-ascertained by both EID and RIA - on purified HBsAg, but not on the native preparation. The inhibition exerted by Bromocet and Hibiscrub indicated by EID results was not confirmed by RIA.

Cetylpyridinium↗

PubMed1995

In vitro oxidative damage to tissue-type plasminogen activator: a selective modification of the biological functions.

OBJECTIVE: Tissue-type plasminogen activator (t-PA) is an important component of the blood fibrinolytic system responsible for thrombus dissolution. It is often required to function under oxidative stress, and exogenous t-PA is used clinically in the treatment of acute myocardial infarction (AMI). The aim of this study was to examine alterations in the residual activity of t-PA pre-treated with certain oxidants. METHODS: Recombinant t-PA (rt-PA) and native t-PA (nt-PA) were pre-treated with freshly generated hypochlorous acid (HOCl) and chloramine T at varying concentrations. The amidolytic activity, the plasminogenolytic activity and the fibrin-binding affinity were then examined using chromogenic assays based on S-2288 and S-2251. RESULTS: The amidolytic activity of t-PA was surprisingly found to be rather sensitive (IC50 1 and 12 mumol/1, respectively), and the plasminogenolytic activity rather resistant to pre-treatment with HOCl and chloramine T. The fibrin binding study of treated t-PA revealed substantial loss of binding to CNBr-digested fibrinogen (FDP-CNBr). The velocity of t-PA in reaction with plasminogen remained the same as non-treated t-PA. The possible mechanisms of this asymmetrical oxidative modification of the biological functions are also discussed. CONCLUSIONS: (1) The catalytic activity of t-PA and the binding affinity for its large-molecule substrate plasminogen, rather than the small-molecule substrate S-2288, are highly resistant to oxidative damage; (2) the fibrin-binding affinity of t-PA can be selectively and asymmetrically damaged by exposure to these oxidants. Thus it is possible that the characteristic advantage of thrombus selectivity of t-PA in both spontaneous thrombolysis and thrombolytic therapy may be diluted in circumstances where toxic and reactive oxidants exist.

Amino Acid Sequence↗

PubMed1975

[Radiolabeling (125I) with high specific activity of the 1-34 N-terminal derivative of bovine parathormone without loss of biological activity].

Radiolabelling of 1-34 N terminal synthetic biological active fragment of bovine parathormone (1-34 bPTH) with high specific activity and without loss of biological activity was studied. Chloramine T and lactoperoxydase methods were used. To assess biological activity of 125I 1-34 bPTH labelled fragment, we use their ability to activate renal cortical adenylate cyclase. Our results show that enzymatic labelling method preserved the biological activity. With the chloramine T method it is possible to keep the biological activity by using DMSO.

Adenylyl Cyclases↗

PubMed1993

[Bacterial flora of the hospital environment: identification, susceptibility to disinfecting agents, antibiotics and chemotherapeutics].

The studies were performed at the Intensive Care Unit of the Institute of Pediatrics. There were aimed at determination of cleanliness of boxes together with ante-rooms. At the same time bacterial flora of hospitalized children was investigated. The bacteria were isolated and identified by classical methods and by the API system. Among the identified strains, 60% constituted Gram-positive cocci with dominant participation of coagulase-negative staphylococci. Gram-negative rods (25% of total bacterial number) were represented mainly by Pseudomonas and Acinetobacter. Determination of susceptibility of tested strains toward 24 antibiotics and chemotherapeutics demonstrated wide occurrence of multiple antibiotic-resistance, particularly among enterococci and Gram-negative rods. Tests for susceptibility to disinfectants revealed presence of strains sensitive to chloramine in concentrations a dozen times higher when compared with standard strains. These strains occurred in the ward after systematic use of this disinfectant for many years. After replacement of chloramine by sterinol and chlorhexidine, these bacteria were not detectable after one year.

Acinetobacter↗

PubMed1976

[Possibility of the development of resistance to disinfectants in microorganisms (author's transl)].

Germs resistant to disinfectants have been found by various authors in hospitals. The question arise whether this is a case of primary resistance or - similar to resistance to antibiotics - a development of resistance takes place. Five fully sensitive laboratory germs were exposed for longer periods of time to sublethal doses of four basic constituents of disinfectants (phenole, isopropanole, formaldehyde, chloramine 80). After a different number of passages an increasing resistance could be noted against formaldehyde and chloramine 80. To date no comments are possible regarding the mechanisms of action.

1-Propanol↗

PubMed2001

Preliminary evidence of toxicity associated with the benthic cyanobacterium Phormidium in South Australia.

In April 2000, the water supply for Yorke Peninsula in South Australia was deemed non-potable when extracts from a proliferation of the benthic cyanobacterium Phormidium aff. formosum in Upper Paskeville Reservoir were found to be lethally toxic by intraperitoneal injection into mice (400 mg kg-1). Routine water quality monitoring had failed to detect the development of the Phormidium until complaints of musty taste and odour, attributable to the production of 2-methyl-isoborneol (MIB), were received from the consumers. The 185 ML open-balancing storage, receiving filtered and chloraminated water from the River Murray, was isolated from the drinking water supply and a health alert was issued to approximately 15,000 consumers. The identity of the toxin(s) is thus far unknown, but clinical symptoms of toxicity in mice and chemical characteristics are distinct from the known major cyanotoxins. Preliminary characterisation of this toxin indicates that it has low solubility in water and organic solvents and is strongly associated with the particulate cellular material of the filaments. Toxicity of extracts was diminished by boiling and by treatment with chlorine, but not by chloramines. Further testing of floating cyanobacterial mats in the Torrens Lake in the city of Adelaide (Phormidium aff. formosum) and Myponga Reservoir (Phormidium aff. amoenum) in 2000/2001 was also found to be toxic by mouse bioassay. Toxicity is yet to be confirmed in monospecific cultured strains and further studies are required to identify the toxin and assess its health significance. Genetic characterisation of isolates has commenced in an attempt to classify their relatedness and to assist in the rapid identification of potentially toxic strains.

Animals↗

PubMed1997

Bacillus thuringiensis delta-Endotoxin Binding Sites in Two Lepidoptera, Wiseana spp. and Epiphyas postvittana

Proteins from the midguts of the light-brown apple moth Epiphyas postvittana (Walker) and the porina caterpillars Wiseana cervinata (Walker), W. copularis (Meyrick), and W. jocosa (Meyrick) which bind the Bacillus thuringiensis delta-endotoxin Cry1Ba were characterized using Cry1Ba labeled with Bolton and Hunter reagent. A comparison of two iodine labeling techniques on the toxicity of B. thuringiensis delta-endotoxins showed that labeling using chloramine-T substantially decreased Cry1Ba toxicity against the light-brown apple moth E. postvittana, whereas labeling using the Bolton and Hunter reagent had no effect on the toxicity of either Cry1Ac or Cry1Ba to this insect. The characteristics of Cry1Ac binding sites from E. postvittana midguts were determined by competitive binding assays using toxin labeled with 125I by both methods. The difference in values of binding site characteristics found by the two methods was shown to be caused by modification of the toxin by the conditions of chloramine-T labeling. The relationship between number and affinity of the binding sites and the toxicity of the delta-endotoxins is discussed.

Journal Article↗

PubMed1998

Myeloperoxidase (MPO) may mediate neutrophil adherence to the endothelium through upregulation of CD11B expression--an effect downregulated by taurine.

Extracellular myeloperoxidase (MPO) is a macrophage modulator which stimulates release of the pro-inflammatory cytokine TNF alpha in addition to reactive oxygen species (ROS) generated by these cells. MPO-induced macrophage secretion of pro-inflammatory mediators indirectly upregulates neutrophil pro-inflammatory capacity through contributing to neutrophil priming for respiratory burst activity. However, to date the question concerning a direct influence on the neutrophil by MPO or the MPO-derived product hypochlorous acid (HOCl) remains to be elucidated. Taurine, the most abundant free amino acid in human neutrophils acts as an antioxidant through the formation of taurine-chloramine by sequestering HOCl. Zinc also has antioxidant properties and taurine-zinc complexes have been shown to have greater efficacy than either agent alone in protection against ROS-mediated tissue damage. The aims of this study were: (a) to determine if extracellular MPO modulates the inflammatory response through autocrine feedback on the neutrophil and to investigate if taurine either directly or indirectly through taurine-chloramine formation may further influence this pathway and (b) to evaluate the efficacy of a taurine-zinc combination in modulating MPO-induced CD11b receptor expression.

Cell Adhesion↗

PubMed1997

Advantage of residualizing radiolabels for an internalizing antibody against the B-cell lymphoma antigen, CD22.

LL2 is an anti-CD22 pan-B-cell monoclonal antibody which, when radiolabeled, has a high sensitivity for detecting B-cell, non-Hodgkin's lymphoma (NHL), as well as an antitumor efficacy in therapeutic applications. The aim of this study was to determine whether intracellularly retained radiolabels have an advantage in the diagnosis and therapy of lymphoma with LL2. In vitro studies showed that iodinated LL2 is intracellularly catabolized, with a rapid release of the radioiodine from the cell. In contrast, residualizing radiolabels, such as radioactive metals, are retained intracellularly for substantially longer. In vivo studies were performed using LL2-labeled with radioiodine by a non-residualizing (chloramine-T) or a residualizing method (dilactitol-tyramine, DLT), or with a radioactive metal (111In). The biodistribution of a mixture of 125I (non-residualizing chloramine-T compared to residualizing DLT), 111In-labeled LL2 murine IgG2a or its fragments [F(ab')2, Fab'], as well as its humanized, CDR-grafted form, was studied in nude mice bearing the RL human B-cell NHL cell line. Radiation doses were calculated from the biodistribution data according to the Medical International Radiation Dose scheme to assess the potential advantage for therapeutic applications. At all assay times, tumor uptake was higher with the residualizing labels (i.e., 111In and DLT-125I) than with the non-residualizing iodine label. For example, tumor/blood ratios of 111In-labeled IgG were 3.2-, 3.5- and 2.8-fold higher than for non-residualizing iodinated IgG on days 3, 7 and 14, respectively. Similar results were obtained for DLT-labeled IgG and fragments with residualized radiolabels. Tumor/organ ratios also were higher with residualizing labels. No significant differences in tumor, blood and organ uptake were observed between murine and humanized LL2. The conventionally iodinated anti-CD20 antibody, 1F5, had tumor uptake values comparable to those of iodinated LL2, the uptake of both antibodies being strongly dependent on tumor size. These data suggest that, with internalizing antibodies such as LL2, labeling with intracellularly retained isotopes has an advantage over released ones, which justifies further clinical trials with residualizing 111In-labeled LL2 for diagnosis, and residualizing 131I and 90Y labels for therapy.

Animals↗

PubMed2000

Kinetics of chlorination of monochlorodimedone by myeloperoxidase.

The phagocyte-derived enzyme myeloperoxidase has been recently implicated in the pathogenesis of atherosclerosis, because it catalyzes the reaction of hydrogen peroxide with chloride ions to give the highly toxic oxidant hypochlorous acid. The aim of this study was to determine the dependence of this reaction on the concentration of hydrogen peroxide and of the enzyme by means of the photometric monochlorodimedone assay. The initial rate of hypochlorous acid formation increased less than proportionally with increasing myeloperoxidase concentrations. Variation of the concentration of hydrogen peroxide had a biphasic effect, with an optimal concentration of hydrogen peroxide. Above this concentration enzyme destruction is apparently predominant. The progress curves of hypochlorous acid formation showed two distinct maxima. It was concluded that hypochlorous acid not only reacts with monochlorodimedone but also with the amino groups of myeloperoxidase to form intermediary chloramines that may further chlorinate monochlorodimedone. This was supported by the kinetics in the presence of the amino compound glycine, a competitive substrate for chlorination by hypochlorous acid. In the presence of high concentrations of glycine the progress curve rises continuously, yielding a greatly increased concentration of chlorinating species, either hypochlorous acid or chloramines. We concluded that glycine protects myeloperoxidase against hypochlorous acid-induced self-destruction.

Binding, Competitive↗

PubMed1995

Cephalosporins are scavengers of hypochlorous acid.

Potential scavenging properties of cephalosporins (i.e. cefamandole, cefotaxime and ceftriaxone) towards hypochlorous acid (HOCl) as well as the antibacterial activity of control and HOCl-reacted antibiotics were investigated. We found that these drugs, at therapeutically relevant concentrations, are indeed scavengers of HOCl, with ceftriaxone showing the highest anti-HOCl capacity. However, the efficiency of cephalosporins in protecting biological molecules is also related to the chemical identity of such molecules. Indeed, the polyenoic compound beta-carotene is much better protected that the thiol compound GSH against HOCl attack. Moreover, the drugs do not appear to form chloramine derivatives as a result of their reaction with HOCl, and they inhibit taurine-chloramine formation. After HOCl challenge, the antibacterial activity of cefamandole, cefotaxime and ceftriaxone (tested against the standard strain Escherichia coli ATCC 25922) is approx. 8-, 5- and 4-fold lower, respectively, than that of the HOCl-unreacted antibiotics. The depression of the antibacterial activity of cephalosporins appears inversely related to their HOCl scavenging capacity, suggesting that the drug antioxidant groups may protect the beta-lactam ring against HOCl attack. In conclusion, physiological biomolecules are protected by cephalosporins against HOCl-driven oxidative injury with varying efficiency, this antioxidant defence being a consequence of a direct drug scavenging capacity towards HOCl. The interaction of cephalosporins with HOCl, however, results in a depression of their antibacterial activity.

Antioxidants↗

PubMed1989

Characterization of the oxidant generation by inflammatory cells lavaged from rat lungs following acute exposure to ozone.

Following exposure to 2 ppm ozone for 4 hr, two distinct effects on rat lung inflammatory cell oxidant generation were observed. TPA- and opsonized zymosan-stimulated superoxide production by the inflammatory cell population was found to be maximally inhibited 24 hr following ozone exposure. In contrast, luminol-amplified chemiluminescence increased 24 hr following ozone exposure, coinciding with an increase in the percentage of neutrophils and myeloperoxidase in the inflammatory cell population. Supporting the involvement of myeloperoxidase in the enhanced oxidant-generating status of these cells, the luminol-amplified chemiluminescence was found to be azide-, but not superoxide dismutase-inhibitable. Additionally, this cell population was found to generate taurine chloramines, a myeloperoxidase-dependent function which was absent prior to the ozone exposure and also demonstrated enhanced activation of benzo[a]pyrene-7,8-dihydrodiol to its light-emitting dioxetane intermediate. Addition of myeloperoxidase to control alveolar macrophages resulted in enhanced luminol-amplified chemiluminescence, taurine chloramine generation, and enhanced chemiluminescence from benzo[a]pyrene-7,8-dihydrodiol demonstrating that, in the presence of myeloperoxidase, alveolar macrophages are capable of supporting myeloperoxidase-dependent reactions. The possibility of such an interaction occurring in vivo is suggested by the detection of myeloperoxidase activity in the cell-free lavagates of ozone-exposed rats. These studies suggest that neutrophils recruited to ozone-exposed lungs alter the oxidant-generating capabilities in the lung which could further contribute to lung injury or to the metabolism of inhaled xenobiotics.

Animals↗

PubMed1981

Binding of iodinated rat and ovine prolactins to prolactin receptors and to its antibodies.

Most studies of prolactin receptors in rat tissues have not used the homologous 125I-labeled rat prolactin as tracers, but rather 125I-labeled ovine or human prolactin. We have compared the effect of different methods of iodination on the specific binding of rat and ovine prolactin to sites in the seminal vesicle of rats and the liver of mice post-partum. Ovine prolactin, either iodinated with lactoperoxidase or with mild chloramine-T (10 micrograms), showed 3 times the specific binding of correspondingly-iodinated rat prolactin. This greater sensitivity of rat prolactin to oxidative damage during iodination, as compared with ovine prolactin is further shown by the difference in Sephadex G-100 elution constant of unlabeled and labeled rat prolactin. . This difference was absent in the case of ovine prolactin. Parallel studies of the binding of the labeled hormone to homologous antibody revealed that immunoreactivity of labeled ovine prolactin was not affected by any of the iodination methods. Rat-prolactin immunoreactivity was depressed by lactoperoxidase iodination as compared with chloramine-T iodination. Rat prolactin was also less potent than ovine prolactin in inhibiting the binding of homologous and heterologous labeled hormone to its receptors, to a larger degree than could be expected from the bioassay potency of the various hormone preparations. These results reflect the greater sensitivity to damage of the biologically active site of rat prolactin, as compared with the ovine hormone.

Animals↗

PubMed1975

The effect of serum and experimental variables on the transferrin and reticulocyte interaction.

The transfer of iron from transferrin to the developing erythrocyte is a research area of high interest and considerable controversy. We have found that the results of transferrin-reticulocyte incubation studies are quite sensitive to the experimental procedures that are utilized. Reticulocytosis has been induced in rabbits by phelbotomy and phenylhydrazine injections. While the latter gives a higher reticulocyte count, the cells appear to exhibit an altered transferrin-membrane interaction. Transferrin has been iodinated by published methods utilizing chloramine-T and molecular iodine. The iodotransferrin products exhibit the same iron donation ability, however, evidence was found that the chloramine-T treatment leads to a nonspecific binding of transferrin to the reticulocyte. The means of saturating transferrin with 59Fe is also of prime importance. Fe(NH4)2(SO4)2 and especially FeCl3 were found to yield nonspecifically bound iron when added to transferrin or serum. This artifact was reflected in an altered transferrin-reticulocyte interaction. Using what we believe to be optimal conditions, the effect of serum on the transferrin-reticulocyte system was re-examined. The results clearly indicated an enhancement of iron uptake by reticulocytes in the presence of serum, as well as an accelerated incorporation of iron by the cytoplasmic fraction.

Animals↗

PubMed1984

Myeloperoxidase reduces the opsonizing activity of immunoglobulin G and complement component C3b.

The effect of myeloperoxidase, hydrogen peroxide (H2O2) and a halide (Cl) on the opsonizing molecules in immunoglobulin G (IgG) and complement factor C3b was assayed. At concentrations of the enzyme (1 microgram/ml) that can be found in the extracellular fluid during inflammation, the myeloperoxidase-H2O2-Cl system inhibited the opsonizing effect of IgG and C3b measured as phagocytic uptake and superoxide generation. The effect was related to the enzymatic peroxidative activity of the protein. The presence of albumin (10 mg/ml) reduced the effect of myeloperoxidase with 10-20%. Taurine, which in the presence of myeloperoxidase-H2O2-Cl forms hydrophilic chloramines, and D-penicillamine, which scavenges HOCl, neutralize the inhibitory effect of myeloperoxidase. This suggests that either hypochlorous acid or lipophilic chloramines may exert its effect by oxidizing free sulphydryl groups exposed on the opsonizing ligands. Since the myeloperoxidase-H2O2-halide system also affects chemotactic factors, leukotrienes, proteinases and membrane receptors, the system may in several ways affect the development of the inflammatory response.

Complement C3b↗