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PubMed1984

Quantitation of types I and III collagens in human tissue samples and cell culture by cyanogen bromide peptide analysis.

A procedure for the quantitation of types I and III collagens by cyanogen bromide peptide analysis was developed with the aim of eliminating certain problems associated with this method. Ion-exchange chromatography reduced high background levels on gel scans used to quantitate the peptides; reduction with beta-mercaptoethanol substantially increased the efficiency of the cyanogen bromide cleavage; use of a concave gradient in acrylamide from 8 to 20% improved the resolution of cyanogen bromide peptides separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis; and a normalization procedure eliminated variations due to differences in the amount of material loaded on the gel system. This method of quantitation was applied to human aorta samples and to collagen secreted by human skin fibroblasts. Metachromasy of type I and type III collagen cyanogen bromide peptides stained with Coomassie blue R-250 was established and this was used as an index of the purity of the cyanogen bromide peptide preparations. Type I and III collagens were prepared from human placental tissue, and these purified collagens were used to construct calibration curves to determine the relationship between the quantity of diagnostic cyanogen bromide peptides present and the composition of the sample in terms of types I and III collagens.

Aged↗
PubMed1990

Formylated peptides from cyanogen bromide digests identified by fast atom bombardment mass spectrometry.

Exposure of proteins to 70% formic acid during cyanogen bromide digestion can result in formation of artifact peaks during subsequent purification by HPLC and detection of [M + H + 28]+ ions during analysis by fast atom bombardment (FAB) mass spectrometry. Following cyanogen bromide digestion, peptides from equine heart cytochrome c, bacteriorhodopsin, bovine adrenal medulla dodecapeptide, and bovine adrenal peptide E were analyzed by positive ion FAB mass spectrometry. The cyanogen bromide peptides of cytochrome c and bacteriorhodopsin showed mixtures of formylated ions, [M + H + 28]+, and nonformylated ions, [M + H]+. Bovine adrenal medulla dodecapeptide and bovine adrenal peptide E were not formylated during digestion. Formylated peptides could be resolved from the corresponding nonformylated peptides using reversed-phase HPLC. Instability of the formylated peptides prevented localization of the adduct by Edman degradation. However, B/E-linked scanning during FAB mass spectrometric analysis with collisional activation of the [M + H + 28]+ ion of a cyanogen bromide peptide from cytochrome c suggested that formylation occurred at a threonine residue. On the basis of stability measurements in aqueous solution and analysis by FAB mass spectrometry, it was determined that serine and threonine residues are the most likely sites of esterification by formic acid during cyanogen bromide digestion of proteins. Furthermore, substitution of 70% trifluoroacetic acid for formic acid during cyanogen bromide digestion eliminated formylation and generated little or no trifluoroacetylation.

Adrenal Medulla↗
PubMed1995

Pharmacokinetic properties of bromide in dogs after the intravenous and oral administration of single doses.

Bromide (20 mg kg-1) was administered intravenously and orally to normal beagle dogs. The mean (SD) apparent elimination half life (t1/2 beta) after oral administration (46 +/- 9 days) was not significantly different from the mean t1/2 beta after intravenous administration (37 +/- 10 days). The mean total body clearance was 9.0 +/- 3.9 ml day-1 kg-1 and the mean apparent volume of distribution was 0.45 +/- 0.07 litre kg-1. The mean area under the serum concentration time curve (AUC) was significantly smaller after oral administration than after intravenous administration, and from a comparison of the two values the oral bioavailability of bromide was estimated to be 46 per cent. Assuming this degree of bioavailability, the daily dose of bromide necessary to maintain serum bromide concentrations within the therapeutic range of 1000 to 2000 mg litre-1 recommended for epileptic dogs was estimated to be approximately 21 mg kg-1. The intravenous loading dose of sodium bromide necessary to reach minimal therapeutic serum bromide concentrations was predicted to be 570 +/- 90 mg kg-1.

Administration, Oral↗
PubMed1983

Toxicity of sodium bromide in rats: effects on endocrine system and reproduction.

Bromide has a low acute oral toxicity, with LD50 values in rodents ranging from 3500 to 7000 mg/kg body weight. It is rapidly absorbed and steady-state serum levels have been reached in rats within 4 weeks. The biological half-life of bromide, and consequently the serum levels, are strongly dependent on chloride intake. Feeding of sodium bromide to rats for 90 days in concentrations of 0, 75, 300, 1200, 4800 and 19,200 mg/kg diet led to a complex of changes in the endocrine system, thyroid activation being the most prominent. Furthermore, in the highest dose groups a decrease in spermatogenesis in the testes and decreased secretory activity of the prostate or a reduction in the number of corpora lutea in the ovaries were found. A three-generation reproduction study of the same dietary concentrations showed in the two highest dose groups a decrease in fertility which appeared to be reversible upon bromide withdrawal. Macroscopically, no changes in the offspring were observed. From these studies a no-effect level for bromide ion of 240 mg/kg diet was determined, corresponding to a tentative Acceptable Daily Intake (ADI) of 0.12 mg/kg body weight. This is in good agreement with a preliminary ADI of 0.1 mg/kg established in an experiment with human volunteers, but is considerably lower than the ADI of 1 mg/kg estimated by FAO/WHO. It is suggested that bromide exerts an inhibitory effect on the thyroid, resulting in an increased hormonal stimulation of this organ by the pituitary gland.

Absorption↗
PubMed2004

Bromide levels in natural waters: its relationship to levels of both chloride and total dissolved solids and the implications for water treatment.

South Australian freshwaters from a wide variety of environments were analysed for bromide and the results correlated with both chloride and total dissolved solids (TDS) concentrations. A linear relationship was obtained which allows chloride data to be successfully used to estimate bromide concentrations. Bromide displayed a slightly better correlation with TDS indicating that an improved estimate of bromide could be made by reference to TDS data which is more easily and commonly obtained, and generally available extensively as historical data. The bromide content in relation to its ratio with both chloride and TDS contents was around seventy percent of the corresponding ratios found in seawater, a finding reported in other published data. The ability to estimate bromide concentrations is a potentially useful tool in the drinking water industry as it enables the assessment of the extent of bromate formation (predicted through the use of mathematical models and other water quality data) which is an important factor when ozonation is being considered as a treatment option, particularly as many water industry regulatory bodies have imposed stringent limits on the levels of acceptable bromate.

Australia↗
PubMed2005

Direct analysis of bromide in human serum by capillary electrophoresis.

The purpose of the present work was the development and validation of a simple, rapid and reliable method for direct bromide quantification in serum based on capillary electrophoresis (CE). The analysis was carried out with an automated capillary electropherograph. Analytical conditions were as follows. Capillary: uncoated fused silica, effective length 50 cm, internal diameter 50 microm; voltage: 20 kV in reverse polarity mode; temperature: 25 degrees C; running buffer: 90 mmol/L sodium tetraborate decahydrate and 10 mmol/L NaCl, pH 9.24; detection: direct UV absorption at 200 nm; sample treatment: dilution of serum 1:10 with the internal standard solution (2 mmol/L thiocyanate). Under the described conditions, bromide ions and internal standard were baseline separated in 7 min. No interferences from other serum components were observed. The analytical sensitivity was characterized by a LOD: 0.05 mmol/L and a LOQ of 0.1 mmol/L. Excellent linearity was verified in the range from 2.5 to 60 mmol/L [y = 0.0746x - 0.0372; R2 = 0.9995 (x = bromide concentration; y = bromide peak area/internal standard (I.S.) peak area)]. Quantitative imprecision in intra-day (n = 7) and day-to-day (n = 7) experiments was always within R.S.D. values <2%. Recovery was quantitative throughout the range of linearity of the method. Clinical cases of infants undergoing potassium bromide therapy for refractory epilepsy were analyzed with results in agreement with literature data. On the basis of these considerations, capillary electrophoresis can be proposed as the method of choice for bromide analysis in serum samples, especially for therapeutic drug monitoring purposes.

Bromides↗
PubMed2006

Evaluating the pharmacoeconomic effect of adding tiotropium bromide to the management of chronic obstructive pulmonary disease patients in Singapore.

OBJECTIVE: To perform a pharmacoeconomic analysis on the treatment of chronic obstructive pulmonary disease (COPD) with the addition of tiotropium bromide. METHODS: Pharmacoeconomic modeling was performed utilizing the efficacy of tiotropium bromide from the literature on different settings and severity of COPD. Reductions in exacerbations, hospitalizations, and number of exacerbation days per year were derived from these studies. Cost of drug treatment, exacerbations, hospitalization, and loss of income were derived from local data in Singapore and reported in Singapore dollars (US$1=S$1.71). A model was constructed to calculate the impact of one-year treatment with tiotropium bromide, and the results were reported for the total incremental cost per year, cost per year needed to reduce one hospitalization in one year, and cost-savings from hospitalizations in one year. Sensitivity analysis were performed for different number of patients treated per year, differing cost of hospitalization, different cost for tiotropium bromide, different impact of tiotropium bromide on clinical outcomes, and the different amount of substitution drug utilized in the comparator group. RESULTS: Using the different clinical effects and looking at the impact on treating 1000, 2000, and 10,000 patients per year, most of the results showed a high level of decrease in overall cost per year that ranged from S$145.40 to S$840.37 per patient treated. Cost per year needed to reduce one hospitalization in one year ranged from S$3217.31 to S$18,148.92. Cost-savings from hospitalizations in one year per patient treated ranged from $57.16 to $322.49. This may contribute as high as 83% of the overall cost saving. Sensitivity analysis supports the cost savings finding. CONCLUSION: Adding tiotropium bromide for severe COPD patients would lead to a significant cost savings for the economy.

Bronchodilator Agents↗
PubMed2003

Bromide affecting drinking water mutagenicity.

The effect of bromide on the mutagenicity of artificially recharged groundwater and purified artificially recharged groundwater after chlorine, ozone, hydrogen peroxide, permanganate, and UV treatments alone and in various combinations was studied. The highest mutagenicity was observed after chlorination, while hydrogen peroxide-ozone-chlorine treatment produced the lowest value for both waters. Chlorinated waters, which were spiked with bromide, had up to 3.7 times more mutagenic activity than waters without bromide after every preoxidation method. 3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) was found to correspond as much as 76% of the overall mutagenicity in the waters not spiked with bromide. MX formation was found to be lower when the treated water contained bromide, implicating the formation of brominated MX analogues. Trihalomethane formation increased when the treated water contained bromide.

Bromides↗
PubMed1997

Expression of the proliferating cell nuclear antigen (PCNA) in the rat thyroid gland after exposure to bromide.

Analysis of expression of the proliferating cell nuclear antigen (PCNA) was used to determine the presumed hyperplastic character of morphological changes in the rat thyroid evoked by bromide administration. Male rats fed by a standard diet with determined iodine and bromine content were given potassium bromide. Control animals received no bromide. Experimental animals were given 10, 50 or 100 mg Br- per 11 drinking water for 16 and 66 days, or 100, 200, 400 mg Br-/l drinking water for 133 days. The thyroids of treated animals showed activation of growth of the epithelial follicular component as well as diffuse and focal microfollicular rearrangement of the parenchyma with higher follicular cells accompanied by a decrease of the amount of colloid even at low bromine concentrations (10-100 mg Br-/l drinking water). Using the PCNA-LI index (PCNA-positive nuclei.100/total number of follicular cell nuclei in the section), immunohistochemical analysis of PCNA in the nuclei of the follicular cells was carried out in parrafin sections. The index was significantly higher in bromide exposed animals (P < 0.01) and correlated well with the histological changes, with bromide concentration and with a increased mitotic activity of the follicular cells. PCNA analysis showed that morphological changes resembling a parenchymatic goitre reflect a microfollicular rearrangement of the thyroid of rats exposed to bromide and have the character of hyperplasia owing to the increased mitotic activity of the follicular epithelium.

Animals↗
PubMed1976

Characterization of the cyanogen bromide fragments of the beta chain of human haptoglobin.

Characterization of the cyanogen bromide (CNBr) fragments of the beta chain of human haptoglobin revealed five major fragments resulting from cleavage of four methionyl residues. The fragments were isolated by gel filtration in guanidine-HCl on Sepharose 6B and Bio-Gel P10 and P60. Compositional analyses of the five cyanogen bromide fragments accounted for 248-253 amino acid residues in agreement with the number of residues determined for the intact beta chain. Most of the carbohydrate was attached to CNBr II. Automated amino-terminal sequence analysis and carboxyl-terminal hydrolysis with carboxypeptidase of the haptoglobin beta chain and cyanogen bromide fragments identified 139 residues, or about 55% of the beta-chain molecule. The placement of the fragments within the beta-chain molecule was established by sequence analysis of whole beta chain and a plasmin cleavage fragment. The position of CNBr V was confirmed by the absence of homoserine or homoserine lactone. Cyanogen bromide reaction of intact haptoglobin 1-1 resulted in the isolation of a beta-chain fragment, CNBr III, covalently attached to the intact alpha1 chain by a single disulfide bond. The beta chain was shown to have primary structural similarities to the chymotrypsin family of serin eproteases. Partial sequence analysis of CNBr V established the region which is comparable to the serine-195 active-site region: /Asp-Thr-Cys-Tyr-Gly-Asp-Ala-Gly-Ser-Ala-Phe/ (residues 189-199, chymotrypsinogen A numbering). The active-site serine-195 is replaced by alanine; however, the specificity residue of the trypsin-like enzymes, Asp-189, is preserved. Several minor cyanogen bromide cleavage products were also identified in yields of up to 15%. These minor cleavage products give evidence that tryptophanyl residues in proteins, or glycoproteins, are also susceptible to cyanogen bromide cleavage.

Amino Acid Sequence↗
PubMed1990

Bromide therapy for pediatric seizure disorder intractable to other antiepileptic drugs.

Triple bromide elixir was used as an adjunctive antiepileptic drug in 11 children whose seizure disorders were intractable to other antiepileptic therapy. The patients' ages ranged from 2 to 17 years. The seizure disorders treated included photosensitive epilepsy (one case), acquired epileptic aphasia (one case), Lennox-Gastaut syndrome (three cases), and symptomatic localization-related epilepsies (six cases). Two patients' seizures completely stopped with bromide therapy. Four patients had a significant and sustained improvement on bromide therapy, while three more had a transient improvement. In these six patients with complete or significant control, the mean therapeutic dose was 33 mg bromide/kg daily, and the mean therapeutic serum concentration was 14.1 mmol/L (range, 4 to 30.5 mmol/L). The combination of bromide with valproate appeared to be particularly effective in these patients. Toxicity was minimal, and in only one patient was the medication stopped, because of anorexia and weight loss. Given the low cost, long half-life, and minimal toxicity when serum bromide concentrations are followed, bromide therapy should be considered as adjunctive antiepileptic drug therapy for patients whose seizures are intractable to other drugs.

Adolescent↗
PubMed1987

Exposure of the skin to methyl bromide: a study of six cases occupationally exposed to high concentrations during fumigation.

1 The effects of exposure of the skin to high concentrations of methyl bromide were studied in 6 cases, who had been unintentionally exposed. 2 Exposure to high concentrations of methyl bromide (approximately 40 g/m3) for 40 min can lead to redness and blistering of the skin. This cannot be prevented by wearing standard protective clothing. 3 Skin lesions show a preference for relatively moist skin areas. 4 Plasma bromide levels were highest immediately following exposure (mean 9.0 +/- 1.4 mg/l) and fell in subsequent hours (mean 6.8 +/- 2.3 mg/l 12 h after the exposure), suggesting absorption of (methyl) bromide through the skin. 5 No systemic effects were noted in this series. 6 Fumigation with methyl bromide should not be done in such a way as to require the presence of workers inside closed areas, where methyl bromide is released.

Adult↗
PubMedDate not supplied

Preferential bromide and pesticide movement to tile drains under different cropping practices.

Subsurface drainage systems are useful tools to study chemical leaching in soils. Our objective was to compare the breakthrough behavior of bromide, atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamid] to tile drains under two fall tillage practices (conventional tillage [CT] with a moldboard plow, and reduced tillage [RT] with a chisel plow) in field plots cultivated with corn (Zea mays L.). Leachate volume were greater in RT than in CT, with no statistical differences. Soil analysis showed that bromide migrated deeper in the soil profile than both herbicides, with little tillage effect. All chemicals were detected in drainage water at the same time and followed an event-driven behavior. Tillage had no effect on atrazine and metolachlor found in drainage water, while bromide concentration peaks were higher in RT than in CT in 1999. Concentration peaks were recorded earlier for atrazine and metolachlor than for bromide. Plots of cumulative relative chemical mass (cumulative mass divided by total mass measured in drainage) as a function of cumulative drainage were mostly linear for bromide, while they were S-shaped for both herbicides. Drainage that corresponded to 50% of relative cumulative mass ranged from 40 to 55% for bromide and from 5 to 28% for both herbicides. Rapid chemical movement to tile drains suggested that preferential flow was important in both CT and RT, and that these tillage practices had little influence on this phenomena.

Acetamides↗
PubMed1987

The toxicology of bromide ion.

Inorganic bromide is widely distributed in nature. Its natural physiological role in animal life is unknown. More than a century ago bromide was introduced in medicine as an antiepileptic drug. Nowadays, man is primarily exposed to bromide via food as the result of use of bromide-containing fumigants in intensive horticulture and in the treatment of food stocks. In this review exposure of man to bromide is described, and the pharmacological and toxicological effects of bromide ion are discussed.

Animals↗
PubMed1992

Low anion gap resulting from unexplained exposure to bromide in a patient with renal amyloidosis.

A patient with nephrotic syndrome secondary to renal amyloidosis was consistently observed to have serum anion gap levels as low as -1 mEq/L and averaging approximately 2 mEq/L. Neither multiple myeloma nor extreme hypertriglyceridemia was present, and the patient's serum albumin concentrations were not low enough to depress the anion gap to this degree. An increased serum bromide level (below the range expected to produce clinical toxicity) was the apparent cause of the low anion gap. The patient's parents, who live in the same apartment, also manifested low anion gaps and inexplicably elevated serum bromide levels. Despite detailed investigation, no environmental or pharmacologic source of bromide was uncovered. Although the source of the bromide in the present instance remains elusive, this report illustrates the necessity to measure serum bromide when a low anion gap cannot be explained by other factors, even when there is no history to suggest bromide exposure.

Acid-Base Equilibrium↗
PubMed2003

Measurement of the extracellular space in brain tumors using 76Br-bromide and PET.

UNLABELLED: Brain edema significantly contributes to the clinical course of human brain tumor patients. There is evidence that an enlargement of the extracellular space (ECS) is involved in the development of brain edema. Although T2-weighted magnetic resonance (T2-MR) images represent brain edema by its increased water content, they do not differentiate ECS enlargement from increased intracellular water content. METHODS: On the basis of the known distribution of bromide in the ECS, we used (76)Br-bromide and PET to measure the regional ECS in 9 brain tumor patients. Transport rate constants and the distribution volume (DV) of (76)Br-bromide in normal brain and tumor were derived from dynamic PET scans and the measured (76)Br-bromide concentration in arterial plasma. We evaluated different models regarding their reliability in estimating the ECS. RESULTS: Assuming that the DV of (76)Br-bromide represents the ECS, robust estimates were possible for all investigated regions. In normal brain, ECS was within a narrow range-for example, occipital lobe, 19.9% +/- 3.1%-and was lower in 2 dexamethasone-treated patients compared with untreated patients. In 7 of 9 tumors, increased ECS ranged between 43.8% and 61.1%. ECS increases were confined to the tumor mass and did not extend into peritumoral edematous brain. Two patients with large hyperintense lesions according to T2-MR images showed normal ECS values within the lesion. CONCLUSION: (76)Br-Bromide PET allows a quantitative measurement of the ECS in brain edema and in normal brain. The discrepancies between lesions shown by T2-MRI and regional ECS enlargement as measured with PET challenge the concept of tumor-induced brain edema.

Adult↗
PubMed1990

Effects of sodium bromide on the biosynthesis of thyroid hormones and brominated/iodinated thyronines.

The influence of bromide on thyroid function was studied in iodine-deficient rats, fed on a diet containing 4-16 g/kg sodium bromide for 4 weeks. Measurement of total and free thyroxine and thyroid-stimulating hormone in blood, as well as the thyroid hormones in the thyroid gland, revealed typical signs of hypothyroidism, which were significantly enhanced by bromide intake. Special attention was paid to the possible formation of bromo/iodosubstituted thyronines in the thyroid. These measurements were performed by high-performance liquid chromatography with off-line radioimmunoassay detection. Such thyroid hormone analogues could be detected in all groups of animals with additional bromide intake, but the amounts were found to be too low to compensate adequately for the reduced amounts of thyroid hormones. The results of this study also indicate that bromide toxicity is dependent upon the state of the iodine supply, which should be taken into account for evaluation of acceptable daily intake values for bromide.

Animals↗
PubMed1990

Bromide interference: is less really better?

Increased serum bromide may result from the ingestion of various drugs and from environmental exposures. Chloride methods that are less susceptible to bromide interference have a clinical disadvantage in that they are less likely to arouse suspicion in cases of bromide toxicity. When there is a clinical suspicion of bromide toxicity, differences among various analyzers in the amount of interference caused by bromide may be exploited to confirm this suspicion and to estimate the concentration of bromide in serum.

Bromides↗