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Sample records for chloramine-t

  1. Preparation and evaluation of radio labelled recombinant human interleukin 2 by improved chloramine T method

    International Nuclear Information System (INIS)

    Iodination by improved chloramine T method was investigated. Iodine was activated with very small quantity of chloramine T (21 fold excess to iodine in molar ratio) and then recombinant interleukin-2 (rIL-2) was added to the mixture. Characteristics of the labelled rIL-2 after purification by reversed-phase HPLC was superior to those by usual chloramine T method or lactoperoxidase method. The specific activity was 0.74-1.11 MBq/μg and the immunoreactivity, biological activity and binding ability to rIL-2 receptors were similar to the intrinsic rIL-2. The improved chloramine T method is useful for iodination of unstable peptides and proteins. (author)

  2. Pyridinium hydrobromide perbromide: a versatile catalyst for aziridination of olefins using Chloramine-T.

    Science.gov (United States)

    Ali, S I; Nikalje, M D; Sudalai, A

    1999-09-01

    [reaction: see text] Pyridinium hydrobromide perbromide (Py x HBr3) catalyzes effectively the aziridination of electron-deficient as well as electron-rich olefins using Chloramine-T (N-chloro-N-sodio-p-toluenesulfonamide) as a nitrogen source to afford the corresponding aziridines in moderate to good yields. PMID:16118868

  3. Radioiodination of interleukin 2 to high specific activities by the vapor-phase chloramine T method

    International Nuclear Information System (INIS)

    Recombinant human interleukin 2 (IL-2) was radioiodinated utilizing the vapor phase chloramine T method of iodination. The method is rapid, reproducible, and allows the efficient radioiodination of IL-2 to specific activities higher than those previously attained with full retention of biological activity. IL-2 radioiodinated by this method binds with high affinity to receptors present on phytohemagglutinin-stimulated peripheral blood lymphocytes and should be useful for the study of receptor structure and function

  4. Acid-base and ionic fluxes in rainbow trout (Oncorhynchus mykiss) during exposure to chloramine-T

    Energy Technology Data Exchange (ETDEWEB)

    Powell, M.D.; Perry, S.F. [Department of Biology, University of Ottawa, 30 Marie Curie Ottawa, Ontario, K1N 6N5 (Canada)

    1998-09-01

    The effects of chloramine-T and its degradation products, sodium hypochlorite (NaOCl) and para-toluenesulphonamide (pTSA), on whole body acid-base and branchial and renal ion (Na{sup +}and Cl{sup -}) fluxes were examined in rainbow trout (Oncorhynchus mykiss). Exposure to chloramine-T (3.5 h, 18 mg l{sup -1}) resulted in increases in plasma total CO{sub 2} but no coincident rise in P{sub a}CO{sub 2} or reduction in blood pH. Exposure of fish to 2, 9 or 18 mg l{sup -1} chloramine-T (3.5 h duration) resulted in a reduction in net acid uptake suggesting the development of a metabolic alkalosis. Exposure to the chloramine-T breakdown product pTSA (dissolved in DMSO) resulted in increased net acid uptake (decreased acid excretion) suggesting a metabolic acidosis. Whole body ion fluxes demonstrated increases in the losses of both Na{sup +}and Cl{sup -} with chloramine-T, NaOCl and pTSA. However, the effect of DMSO alone could not be isolated. Confirmatory studies using fish in which the urinary bladder (to allow collection of urine) and dorsal aorta (to allow injection of [{sup 14}C]polyethylene glycol 4000 ([{sup 14}C]PEG), an extracellular fluid marker) were catheterised, revealed that changes in whole body ion fluxes during chloramine-T exposure could not be explained by increased renal efflux through urine flow, glomerular filtration or renal clearance. Branchial effluxes of [{sup 14}C]PEG were not significantly affected by chloramine-T exposure suggesting that the changes in whole body ionic fluxes were caused by transcellular rather than paracellular processes. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  5. Effect of chloramine-T labeling conditions on the stability of monoclonal antibodies and their fragments

    International Nuclear Information System (INIS)

    Rapid in vivo degradation of radioiodinated monoclonal antibodies (MAb) has been reported. Conditions for radioiodination have varied. The purposes of this study were to compare the stability of MAb and their fragments when iodinated with chloramine-T (CT) under different conditions, and to compare methods for quality assessment of the radioiodinated molecules. A B-cell lymphoma MAb (Lym-1, IgG2a) and its FAb fragment, and a mammary cancer MAb(B6.01, IgG1) and its F(Ab')/sub 2/ fragment were iodinated with I-125 at CT:AB and I:Ab ratios of 1:1 and 1:10. Molecular sieving (TSK-3000) high performance liquid chromatography (HPLC), cellulose acetate electrophoresis (CAE) at 11 and 45 minutes and solid phase immunoreactivity (IRA) were used to observe stability of the molecules when stored at 40C. Radiochemical yield was greater than 95% in all instances. Iodination at CT:Ab and I:Ab ratios of 1:1 induced progressive degradation in all species which was most marked for the fragments. Iodination at CT:Ab and I:Ab ratios of 1:10 resulted in no observable degradation over 21 days. There was no significant difference in degradation between the IgG2a and IgG1 antibody when iodinated under identical circumstances. HPLC, CAE for 11 minutes and IRA, but not CAE for 45 minutes, revealed comparable changes. The authors conclude that lesser amounts of chloramine-T can be used to iodinate MAb and their fragments without loss of radiochemical efficiency and with improved stability of the species. MAb fragments are more vulnerable to chloramine-T. These observations may explain, at least in part, rapid in vivo degradation of radioiodinated MAb

  6. Chloramine-T as labelling agent for oleic acid and olive oil

    International Nuclear Information System (INIS)

    Olive oil and its main constituent, oleic acid, have been labelled with 125I using chloramine-T (CAT) as an oxidizing agent. The maximum yields of labelling in different organic solvents were found to vary between 10 to 50% for oleic acid. The values for olive oil were 70% of those of oleic acid. The labelled compounds were stable in organic solvents except acetone where they start to decompose after 20 minutes of starting the experiments. The low yields could be attributed partly to a possible labelling of CAT or to the reaction of CAT with labelled compounds or their precursors. (author)

  7. Using micro-quantity of chloramine T in chicken pro-latin labelling and radioimmunoassay

    International Nuclear Information System (INIS)

    A radioimmunoassay was developed for measurement of chicken plasma prolactin. The assay used chPRL(AFP-10328B) as reference standard, chPRL(AFP-4444B) as the radio labelled ligand, rabbit anti-chicken PRL (AFP-151040789) as first antibody, and donkey anti-rabbit IgG antiserum as second antibody. For iodide ratio labelling of chicken PRL, a modified chloramine T method which reduced the amount of chloramine T and omitted sodium metabisulfite, and produced the labelled hormone with a specific activity of 29μCi/μg was used. The assay sensitivity was 0.34 ng/ml. the ED75, ED50 and ED25 of standard curve were 1.30, 3.71 and 10.60 ng/ml, respectively. Both coefficients of variations between and within assay were less than 15%. Serial dilutions of chicken samples showed a parallel inhibition curve to that of the standards. Plasma PRL concentrations of samples from hens at different reproductive states measured by this assay revealed significant differences and rational changing trends. These results validate the assay

  8. Optimization of the chloramine T method for radioiodination of prostate gland by acid phosphatase

    International Nuclear Information System (INIS)

    Optimal conditions for preparation of [125I]-labelled human prostatic acid phosphatase (PAP) by chloramin T method were developed which make it possible to increase the radiochemical yield and immunoreactivity of labelled PAP. The influence of buffer system, pH of reaction mixture and molarity of borate buffer was investigated. Iodination in 0.2 M borate buffer, pH 8.0 make it possible to prepare [125I]-PAP with 90-98 immunoreactivity. Under storage of labelled PAP during 2 month immunoreactivity is decreased only by 10%. On the base of prepared 125I]-PAP high-sensitive competitive radioimmunoassay of PAP in human serum have developed

  9. Preparation of bromine-77 labelled monoclonal anti-hPLAP [human placental alkaline phosphatase] antibody using chloramine-T

    International Nuclear Information System (INIS)

    A tumor-associated monoclonal antibody, named 7E8 and raised against human placental alkaline phosphatase (hPLAP), is labelled with bromine-77 by means of chloramine-T. The paper describes optimum radiobromination conditions resulting in 34 % radiochemical yield of labelled antibody with more than 90 % immunoreactivity. (author)

  10. Spectrophotometric determination of bio-active compounds with chloramine-T and gallocyanine.

    Science.gov (United States)

    Sastry, C S; Srinivas, K R; Prasad, K M

    1996-10-01

    A simple, sensitive and selective method for the spectrophotometric determination of drugs, viz., sulphamethoxazole, tetracycline HCl, amidopyrine, nifurtimox and isoniazid and biologically important amino acids, cysteine, aspartic acid and arginine based on their reactivity with chloramine-T (CAT) is proposed. The method involves the addition of excess CAT of a known concentration in the presence of 0.25 M HCl and the determination of the unreacted CAT by measurement of the decrease in the absorbance of the dye, gallocyanine (lambda(max): 540 nm), the most suitable of several dyes that were tested. This method was applied to the determination of drug contents in pharmaceutical formulations and to the measurement of the aspartic acid content of some protein hydrolysates. The method is useful for the determination of the target compounds in microgram quantities from 0.4-5.6 microg mL(-1) with the exceptions of arginine (1.0-8.0 microg mL(-1)) and nifurtimox (0.8-5.6 microg mL(-1)). Standard deviations were typically 0.5 mg per dose (RSD 0.5-1.2%). No interferences were observed from common excipients in formulations, and detailed interference studies of other amino acids in the determination of cysteine, aspartic acid and arginine are reported. The validity of the method was tested against spectrophotometric and titrimetric reference methods. Recoveries were 99.8-102.1%. PMID:18966644

  11. Radioiodination of olive oil VIA iodinemonochloride and chloramine-T in organic medium

    International Nuclear Information System (INIS)

    Olive oil is one of the neutral oils, composed of many fatty acids, some are saturated while others are unsaturated. This paper reports the results of comparative radioiodination study performed using iodine mono chloride I CI and chloramine-T as oxidising agents in organic solvents. On labelling using 125 I Cl in different solvents, benzene, petroleum ether, diethyl ether and n-heptane a yield of > 70% was found in case of diethyl ether within 5 minutes for olive oil while it was 80% for oleic acid under the same conditions. In case of benzene as a solvent the labelling yield was reached a maximum labelling of 37% and > 43% for olive oil and oleic acid respectively within 60 minutes after which labelling decreased with time. So benzene was chosen as the solvent for labelling of oleic acid using commercial 125 I Cl to compare with I CI prepared in the laboratory. Using unpurified commercial 125 I CI as labelling agent a yield of 65% was reached within 15 minutes while purified commercial I CI gave ∼ 40% after 15 minutes and 22% using the prepared 125 I CI. This reduction in the yield in case of purified I CI indicates that other iodine species I2, I-3 and I OH plays great role in the labelling process depending on the medium used. Further studies were carried out using method for labelling olive oil as well as oleic acid in organic solvents n-heptane, benzene, acetone and methyl n-butyl ketone (MnBK) at a temperature just below the boiling point of each solvent. A maximum labelling yield of 28% for olive oil in the n-heptane solvent against 50% labelling yield of oleic acid under the same conditions of solvent, temperature and reaction time. Using actions as solvent it was found that the labelling yield decreases with reaction time.4 fig

  12. Mechanistic chemistry of oxidation of balsalazide with acidic chloramine-T and bromamine-T: A comparative spectrophotometric kinetic study

    Indian Academy of Sciences (India)

    Puttaswamy; S Dakshayani

    2014-11-01

    Balsalazide (BSZ) belongs to a class of non-steroidal anti-inflammatory drugs. Kinetics and mechanism of oxidation of BSZ with sodium N-halo-p-toluenesulfonamides viz., chloramine-T(CAT) and bromamine-T(BAT) in HClO4 medium have been spectrophotometrically investigated (max =357nm) at 303 K. Under comparable experimental conditions, reactions with both the oxidants follow a first-order dependence of rate on [BSZ] and fractional-order dependence on each [oxidant] and [HClO4]. Activation parameters and reaction constants have been computed. 2-hydroxy-5-nitroso-benzoic acid and 3-(4-nitroso-benzoylamino)-propionic acid are identified as the oxidation products of BSZ with both CAT and BAT. The rate of oxidation of BSZ is about five-fold faster with BAT than with CAT. Plausible mechanism and related rate law have been deduced for the observed kinetics.

  13. Influence of chloramine T iodination on the biological and immunological activity or the molecular radius of the human growth hormone molecule

    International Nuclear Information System (INIS)

    Potential alterations of the somatotropic activity of human growth hormone (hGH) resulting from Chloramine T labelling reaction, iodination up to 2.7 atoms/molecule and indirect radiation effects, have been studied. Three 2X2 factorial assays, performed in hypophysectomized rats, failed to reveal any significant difference (P greater than 0.05) in true growth promoting activity between hGH and (127-I)hGH, even after storing the latter with 125-I. Similar results were obtained applying a sensitive and precise gel filtration technique for Stokes Radius determination and radioimmunoassay

  14. Effects of sub lethal concentration of Chloramin T on growth, survival, haematocrit and some blood biochemical parameters in common carp fry (Cyprinus carpio

    Directory of Open Access Journals (Sweden)

    Mohamad R. Imanpoor

    2011-07-01

    Full Text Available This study was done in Gorgan University of Agricultural Sciences and Natural Resources, in 2009, during 8 weeks to survey effects of different concentrations of Chloramin T on fry common carp (Cyprinus carpio (Linnaeus, 1758. According to the pre experiment data, lethal concentration, the lowest observed effect concentration, maximum allowable toxicant concentration and No Observed Effect Concentration of Chloramin T (Halamid in common carp (C. carpio fry were respectively 40.9, 27.1, 4.90 and 11.28 mg/L-1. Hence, the range of our experiment was between 0 to 25 mg L-1 which was divided to five treatments (0, 5, 10, 15 and 25 mg/L-1. At the end of experiment we calculated growth factor (special growth rate and food conversion ratio and stress indices (glucose total protein and percent of haematocrit and then they were compared with the controlled group. Our study results showed no significant difference between percentage of increase in body weight (280.4±25.79 - 200.4±10.16, special growth rate (2.34±0.25 - 1.96±0.06 and food conversion ratio (0.84±0.05 - 0.60±0.12 in experimental lots of fishes. There is also no significant difference between glucose (146.82±0.79 - 99.54±1.89 and total protein (3.61±0.45 - 2.82±0.06 in experimental groups (P>.05. However there is a significant difference between the percentages of haematocrit (57.34±4.99 - 40.74±2.17 and cholesterol (362.05±24.38 - 134.92±17.59 in these groups (P<0.05.

  15. Fluorous Analogue of Chloramine-T: Preparation, X-ray Structure Determination, and Use as an Oxidant for Radioiodination and s-Tetrazine Synthesis.

    Science.gov (United States)

    Dzandzi, James P K; Beckford Vera, Denis R; Genady, Afaf R; Albu, Silvia A; Eltringham-Smith, Louise J; Capretta, Alfredo; Sheffield, William P; Valliant, John F

    2015-07-17

    A fluorous oxidant that can be used to introduce radioiodine into small molecules and proteins and generate iodinated tetrazines for bioorthogonal chemistry has been developed. The oxidant was prepared in 87% overall yield by combining a fluorous amine with tosyl chloride, followed by chlorination using aqueous sodium hypochlorite. A crystal structure of the oxidant, which is a fluorous analogue of chloramine-T, was obtained. The compound was shown to be stable for 7 days in EtOH and for longer than three months as a solid. The oxidant was effective at promoting the labeling of arylstannanes using [(125)I]NaI, where products were isolated in high specific activity in yields ranging from 46% to 86%. Similarly, iodinated biologically active proteins (e.g., thrombin) were successfully produced, as well as a radioiodinated tetrazine, through a concomitant oxidation-halodemetalation reaction. Because of its fluorous nature, unreacted oxidant and associated reaction byproducts can be removed quantitatively from reaction mixtures by passing solutions through fluorous solid phase extraction cartridges. This feature enables rapid and facile purification, which is critical when working with radionuclides and is similarly beneficial for general synthetic applications. PMID:26030355

  16. Critical evaluation of the radioiodination of follicle-stimulating-and luteinizing hormones by lactoperoxidase and its comparison with chloramine-T classical method

    International Nuclear Information System (INIS)

    A method is described for the enzymatic radioiodination of human gonadotropins by a system consisting of lactoperoxidase, hydrogen peroxide and Na125I. A comparison witth the clhloramine-T modified technique was done a satisfactory specific activity (100 μCi/μg) of the labeled hormone was obtained with the enzymatic iodination, with much greater immunoreactivity and stability than after chloramine-T. As aqueous polyethylene glycol causes precipitation of antibody-bound peptide hormones with radioactive iodine with little or no precipitation of free hormones, a method of separation was developed and applied to radioimmunoassay of gonadotropins, providing several advantages over te double-antibody precipitation method. It was demonstrated that, in humans, the intravenous administration of synthetic LH-FSH/RH, stimulates the pituitary release of both LH and FSH. Results are reported now for normal women, infused with an acute load of 25μg of synthetic LH/FSH-RH and 8 hours infusion of 100μg, during the mid-follicular and luteal phases. The greatest gonadotropin responsiveness to LH/FSH-RH are found in the luteal phase during acute testing. No differences were noticed during chronic infusion as well as acute post-chronic, performed in both phases of the menstrual cycle. The possible modulating effects of steroidal secretion by the ovaries are discussed. (Author)

  17. Use of chloramine-T and two dyes in the sensitive determination of stavudine in pharmaceuticals Uso de cloramina-T e de dois corantes na determinação sensível de estavudina em medicamentos

    Directory of Open Access Journals (Sweden)

    Kanakapura Basavaiah

    2007-09-01

    Full Text Available Three new methods are described for the assay of stavudine (STV in bulk drug and in dosage forms using chloramine-T (CAT and two dyes, methyl orange and indigocarmine, as reagents. Titrimetry involves treating STV with a measured excess of CAT in hydrochloric acid medium, and after the oxidation of STV is judged to be complete, the unreacted oxidant is determined iodometrically. Spectrophotometric methods entail the addition of a known excess of CAT to STV in hydrochloric acid medium followed by determination of residual oxidant by reacting with a fixed amount of either methyl orange and measuring the absorbance at 520 nm (Method A or indigo carmine and measuring the absorbance at 610 nm (Method B. In all the methods, the amount of CAT reacted corresponds to the amount of STV. In titrimetric method, the reaction follows 1:1 stoichiometry (STV: CAT, and is applicable over the range 1.5-10 mg of STV. In spectrophotometric methods, the absorbance is found to increase linearly with concentration of STV. The systems obey Beer's law for 0.2-2.0 and 1.0-10.0 mg/mL for method A and method B, respectively. The apparent molar absorptivities are calculated to be 5.7x10(4 and 1.5x10(4 L/mol/cm for method A and method B, respectively, and the corresponding Sandell sensitivity values are 0.004 and 0.015 µg/cm². The limits of detection and quantification are reported for both methods. Intra-day and inter-day precision and accuracy of the developed methods were evaluated as per the current ICH guidelines. The methods were successfully applied to the assay of STV in tablet and capsule formulations and the results were compared with those of a reference method by applying Student's t-test and F-test. No interference was observed from common tablet adjuvants. The accuracy and reliability of the methods were further ascertained by performing recovery experiments via standard-addition method.Descrevem-se três novos métodos para o ensaio de estavudina (STV na mat

  18. Preparation of iodine - 125 - labeled insulin for radioimmunoassay: comparison of chloramine T and iodogen iodination

    International Nuclear Information System (INIS)

    Stoichiometric iodination of porcine insulin was performed to the general method of Hunter and Greenwood with modifications recommended by Roth. These method was compared with radioidination using Iodogen. Films of Iodogen react rapidly in the solid phase with aqueous mixtures of I -and proteins. For two methods satisfactory activity of the labeled porcine insulin was obtained and characteristics of the radioimmunoassay were studied. (author)

  19. Preparation of high-quality iodine-125-labelled pituitary human follicle-stimulating hormone (hFSH) for radioimmunoassay

    International Nuclear Information System (INIS)

    A method is described for the enzymatic radioiodination of human follice-stimulating hormone (hFSH) by a system consisting of lactoperoxidase, hydrogen peroxide and Na125I. It is compared with the chloramine-T modified technique. A satisfactory specific activity of the labelled hormone is obtained with the enzymatic iodination, with much greater immunoreactivity and stability than with chloramine-T

  20. Chloramine-induced anaphylaxis while showering: a case report

    Directory of Open Access Journals (Sweden)

    D’Alò Simona

    2012-09-01

    Full Text Available Abstract Introduction Sodium-N-chlorine-p-toluene sulfonamide, commonly known as chloramine-T, is a derivative of chlorine which is widely used as a disinfectant. For many years, chloramine-T has been described as a cause of immediate-type hypersensitivity, especially with regard to asthma and rhinitis, and as a cause of occupational dermatoses in cleaning personnel in hospitals, although no anaphylactic reaction has yet been reported. Hence, to the best of our knowledge we present the first case of anaphylaxis to chloramine-T with evidence of specific immunoglobulin E antibodies. Case presentation We describe the case of a 25-year-old Caucasian woman who was in good health and with a negative history for atopy, including no respiratory symptoms of rhinitis or asthma, and with no professional exposure to chloramine-T. She, while showering, applied a chloramine-T solution to a skin area with folliculitis on her leg, and within a few minutes developed generalized urticaria and angioedema, followed by vomiting and collapse with loss of consciousness. A skin prick test with a chloramine-T solution at 10mg/mL concentration was positive, and specific immunoglobulin E to chloramine-T was quantified at a value of 2.9 optical density as measured by the enzyme allergosorbent test technique. Conclusion The strict cause-effect relationship and the results of the skin test and the in vitro test make certain the causative role of chloramine-T in this case of anaphylaxis. This suggests that chloramine-T, based on its wide use as a disinfectant, should be considered a possible cause in anaphylaxis of unknown origin.

  1. Variations of the pharmakocinetic in rabbits of the monoclonal antibody ior t1 produced by the radioiodonation with the chloramina T and iodogen methods

    International Nuclear Information System (INIS)

    The monoclonal antibody ior t1, an IgG2a was labeled with 125I, using the chloramine T and iodogen methods. Immunoreactivity against human lymphocites in vitro was affected in a significant way, mostly with chloramine T methods. In F1 male rabbits, the plasma radioactivity declined in apparently bioexponential manner in the administration of unlabeled ior t1, measured by an specific ELISA to murine IgG, and with the use of chloramine T. A monoexponential declined with the iodogen reagent was observed. We consider the possible of an unspecific binding in blood in the experiment with iodogen reagent. The t-tes student analysis show significant differences between the unlabeled protein and both methods of radioiodination, that differences must be have their origin in the high specific activity when labeled with chloramine T and in the probably of non-specific binding when we employs the iodogen reagents

  2. Radioiodination of melagenine-II with I-125 (preliminary study)

    International Nuclear Information System (INIS)

    Radioiodination of Melagenine-II with I-125 farmacokinetic studies was made, using Chloramine-T method. Radiochemical purity and stability of the labelled product were determined by radiochromatography. The labelled Melagenine-II showed two radioactive fractions

  3. Radio-labeling of polyethylene glycol modification of recombinant human interleukin-6

    International Nuclear Information System (INIS)

    Iodine-125 was used as labeling nuclide, and the PEG-rhIL-6 was labeled by the common used chloramines-T and the two-phase chloramines-T, respectively. The labeled compound was purified by both methods of gel filtration and ultrafiltration respectively. The purity of the labeled PEG-rhIL-6 was determined by both trichloroacetic acid (TCA) and SDS-PAGE, and the biological activity was determined by MTT method. The results demonstrated that the labeling rate and specific radioactivity were 74.5% and 5.513 x 105 Bq/μg for PEG-rhIL-6 by the two-phase chloramines-T method, higher than that by the common used chloramines-T method, which was 62.3% and 4.610 x 105 Bq/μg respectively. The purity of labeled PEG-rhIL-6, purified by both gel filtration and ultrafiltration methods, was over 99% with TCA method. The labeled PEG-rhIL-6 by two-phase chloramines-T method showed two bands, which was identical to that of standard PEG-rhIL-6 though SDS-PAGE, but the labeled PEG-rhIL-6 by common used chloramines-T method had one more band compared with standard PEG-rhIL-6. When determined by MTT, it shown that the biological activity of PEG-rhIL-6 iodinated by common used chloramines-T method was lower than that by two-phase chloramines-T method. (authors)

  4. The effect of chemical anti-inhibitors on fibrinolytic enzymes and inhibitors

    DEFF Research Database (Denmark)

    Sidelmann, Johannes Jakobsen; Jespersen, J; Kluft, C;

    1997-01-01

    proteases. We studied the influence of chemical anti-inhibitors (chloramine T, flufenamate, sodium lauryl sulfate, and methylamine) on fibrinolytic serine proteases and fibrinolytic enzyme inhibitors using the physiological substrate fibrin as plasmin substrate. Low concentrations of chloramine T (0.01 mmol...... plasminogen activators (apparent recovery > 200%). Sodium lauryl sulfate eliminates the major fibrinolytic enzyme inhibitors, but increases the activity of plasmin (apparent recovery > 200%) and plasminogen activator, urokinase type (apparent recovery 130%). Methylamine affects only plasmin inhibition. We...

  5. Differences in the pharmacokinetic and biodistribution in rates of the monoclonal antibody 125I-ior t1 due to I use of different methods of iodogen direct

    International Nuclear Information System (INIS)

    The monoclonal antibody ior t1, an IgG2a, was labeled with 125I, using the chloramine T, iodogen and iodine monochloride methods produce an important deiodination, demonstrated by ascending paper chromatography and the similarities between his serum profile respect to the radioactivity serum profile of the free 125I in Wistar rats. The plasma radioactivity declined in apparently bioexponential manner with the use of chloramine T and iodine monochloride, and show a monoexponential declined with the iodogen reagent. The pharmacokinetic of 125I ior t1, in the chloramine T methods, was very erractic. We consider the possible of an unspecific binding in blood in the experiment with iodogen reagents. The biodistribution show a similar pattern with other IgG2a in rats

  6. 125I radiolabelling of 1-34 N-terminal tetratiacontapeptide of bPTH with high specific activity and without destroying biological activity

    International Nuclear Information System (INIS)

    Radiolabelling of 1-34 N terminal synthetic biological active fragment of bovine parathormone (1-34 b PTH) 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, their ability to activate renal cortical adenylate cyclase was used. The 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

  7. Labelling of human follicle stimulant hormone with 125I, for radioimmunoassay

    International Nuclear Information System (INIS)

    An efficient labeling of human Follicle Stimulant Harmone is essential to development of sensitive radioimmunoassays. Iodination by Chloramine T method frequently is subject to severe iodination damage and some preparations are unaccetable for radioimmunoassays. Modifications to the Hunter method, changing incubation time, reaction temperature and reducing Chloramine T amount used in the reaction, were performed in obtaining a more effective labeling. FSH-125 I fraction obtained from Sephadex G-75 column purification presented excellent immunoreactivity and quality control of the steps of the reaction demonstrated a high percentage (90%) of intact Follicle Stimulant Hormone

  8. Comparison of the ribonucleoproteins of different rabies virus serotypes by radioimmunoassay

    International Nuclear Information System (INIS)

    Radioimmunoassay (RIA) provides a sensitive serological procedure for detecting rabies virus ribonucleoprotein (RNP) as well as its specific antibodies. RIA was carried out using highly purified RNPs labelled by the chloramine-T method. This paper describes optimal conditions for iodination of RNP with high specific activity. The optimal concentrations of 125I, RNP, chloramine-T, and reducing agent as well as the effect of pH on the reaction were investigated. RIA proved to be extremely sensitive for detection of homologous antibodies. In competition experiments the part-relationship of the group-specific RNPs of the three rabies virus serotypes (HEP, MOK and LBV) was confirmed

  9. Preparation of 125I-protein A usable for up to 10 months in immunoassays

    DEFF Research Database (Denmark)

    Dyrberg, T; Billestrup, Nils

    1984-01-01

    Chloramine-T iodination of protein A from Staphylococcus aureus and gel electrophoretic purification of the iodination mixture results in a stable tracer of high specific and functional activity. Following repeated gel electrophoresis of the tracer only a single component was observed. The specif...

  10. Improved radioimmunotherapy of hematologic malignancies. Progress report, November 1, 1993--October 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Press, O.W.

    1994-08-04

    This report summaries progress made during the time interval between November 1, 1993 and October 31, 1994 and briefly describes studies on the metabolism of antibodies targeting B cell antigens, retention of labeled antibodies by human B cell lymphocytes, and tissue distribution of Chloramine T and tyramine cellobiose labeled antibodies in mice harboring a human erythroleukemia tumor transplant.

  11. Treatment of trichodiniasis in eel ( Anguilla anguilla ) reared in recirculation systems in Denmark : alternatives to formaldehyde

    DEFF Research Database (Denmark)

    Madsen, H.C.K.; Buchmann, Kurt; Mellergaard, Stig

    2000-01-01

    parasiticidal effect: acriflavin (25 ppm), bithionol (0.1 ppm), chloramine T (50 ppm), Detarox AP(R) (45 ppm), malachite green (1 ppm), raw garlic (200 ppm), potassium permanganate (20 ppm) and Virkon PF(R) vet. (20 ppm). Preliminary screening revealed that the anthelmintic, bithionol, and the decomposable...

  12. Immunoreactivity of 125I-papain labelled by different methods

    International Nuclear Information System (INIS)

    Three different methods of papain iodination (with chloramine-T, lactoperoxidase and conjugation with Bolton-Hunter reagent) have been compared. The highest yield of 125I-papain could be obtained using lactoperoxidase which enabled to achieve the highest immunoreactivity. 125I-papain, labelled this way, is suitable for the radioimmunoassay of papain. (author)

  13. The dinoflagellates Pfiesteria shumwayae and Luciella masanensis cause fish kills in recirculation fish farms in Denmark

    DEFF Research Database (Denmark)

    Moestrup, Øjvind; Hansen, Gert; Daugbjerg, Niels;

    2014-01-01

    apparently the first RAS farms in which serious fish kills have been reported. In the marine farm (Luciella) fish mortality increased dramatically despite treatment of the water with peracetic acid and chloramine-T. The plant was temporarily closed down pending investigation into the cause of mortality and...

  14. One-pot synthesis of new series 3,4,5-trisubstituted-dihydroisoxazoline derivatives via 1,3-dipolar cycloaddition of nitrile oxides with chalcones

    Indian Academy of Sciences (India)

    Raad Kasim Yhya; K M Lokanatha Rai; Ebraheem Abdu Musad

    2013-07-01

    We have synthesized a series of novel isoxazolines via 1,3-dipolar cycloaddition reaction. Aromatic aldoximes undergo oxidative-dehydrogenation with chloramine-T to give nitrile oxides, which were reacted with chalcones to afford of 3,4,5-trisubstituted 4,5-dihydroisoxazolines in a good yield.

  15. Synthesis of new series of 4, 5-dihydroisoxazole-5-carboxylate derivatives for the study of their liquid crystalline properties

    Indian Academy of Sciences (India)

    SUMANA Y KOTIAN; NARAYANA U KUDVA N; K M LOKANATHA RAI; K BYRAPPA

    2016-07-01

    A new series of 4,5-dihydroisoxazole-5-carboxylate derivatives were synthesized via [3+2] cycloaddition reaction between ethyl acrylate and nitrile oxide generated in situ in presence of Chloramine-T. The synthesized derivatives were characterized by Mass, IR and NMR Spectroscopy and their mesomorphic behavior were studied using DSC and Polarising Optical Microscopy.

  16. Synthesis and radioiodination of analogues of substance P for the building up of a radioimmunoassay

    International Nuclear Information System (INIS)

    The substance P (SP) analogs [Lys(MSOC)3]-SP, [Tyr8]-SP, [Tyr8,Nle11]-SP and [p-HPA1]-SP have been synthesized by classical methods of peptide synthesis as well as by the liquid phase peptide synthesis (LPPS) to allow conjugation with protein in the Nα-position and radioiodination. [Tyr8]-SP and [p-HPA-Arg1]-SP have been radioiodinated by the chloramine T- and the lactoperoxidase method. A complete S-oxidation of SP was observed, when the chloramine T procedure was used, but this modification does not disturb the assay. The introduction of the [125I-pHPA-Arg1]-SP-tracer led to considerable improvements of our SP-radioimmunoassay. (author)

  17. Labelling of human serum albumin with iodine-131 for diagnosis in nuclear medicine

    International Nuclear Information System (INIS)

    Labelling of 131I-human serum albumin with I-131 from a solution of 131I-sodium iodide using chloramine T as an oxidant agent is studied. Parameters which can influence on the labelling yield like mass of human serum albumin, and chloramine T, pH of the reaction, reaction time and activity of 131I are also studied. The purification of the labeled product by means of IRA-410 Amberlite ion-exchange resin in chloride form and the sterilization of the 131I-human serum albumin by its passage through a 0,22μ millipore filter are carried out. The radiochemistry control of the final product by paper chromatography and the microbiological control by cultivation of microorganisms in fluid medium: nutrient broth, sodium thioglycollate broth and Sabouraud, are performed. The stability of the radiopharmaceutical until ten days after its preparation is analysed by means of radiochemical control. (Author)

  18. Preparation and Evaluation of (125I) Daunorubicin as a Potential Agent for Tumor Detection and radiotherapy

    International Nuclear Information System (INIS)

    In this study, the optimization of daunorubicin labeling with iodine-125 and its biological evaluation were described. Daunorubicin was labeled via direct electrophilic substitution using chloramine-T as oxidizing agent. The optimum amounts of reactants were: 40μg daunorubicin, 30μg Chloramine-T and ∼ 19 KBq carrier free Na125I. The labeled daunorubicin was stable for more than 24 hours. Results of the in-vivo evaluation revealed that the tracer, [125I] daunorubicin, tends to localize in tissues with high proliferation rate with preferential accumulation in cancerous tissues. Imaging should be carried at 3 hours post injection. The in-vitro cell growth inhibition assay showed that the effect of [125I] Daunorubicin was stronger than the effect of cold daunorubicin which strongly suggested that its cytotoxicity was mainly due to radiotoxicity rather than chemotherapeutic activity.

  19. Kinetics and Mechanism of Electron Transfer Reaction: Oxidation of Sulfanilic Acid by N-Chloro-p-Toluene Sulfonamide in Acid Perchlorate Medium

    Energy Technology Data Exchange (ETDEWEB)

    Sailani, Riya; Bhasin, Meneka; Khandelwal, C. L.; Sharma, P. D. [Univ. of Rajasthan, Jaipur (India)

    2014-01-15

    The kinetics and mechanism of oxidation of sulfanilic acid by N-chloro-p-toluene sulfonamide (chloramine-T) have been studied in acid medium. The species of chloramine-T were analysed on the basis of experimental observations and predominantly reactive species was taken into account for proposition of most plausible reaction mechanism. The derived rate law (1) conforms to such a mechanism. All kinetic parameters were evaluated. Activation parameters such as energy and entropy of activation were calculated to be (61.67 ± 0.47) kJ mol{sup -1} and (-62.71 ± 2.48) JK{sup -1}mol{sup -1} respectively employing Eyring equation.

  20. Development and applications of a radioimmunoassay to human plasma kallikrein

    International Nuclear Information System (INIS)

    A radioimmunoassay to human plasma kallikrein (Hu PK) was developed using specific antibodies against the purified activates enzyme. The antiserum showed identity in the precipitation, double immuno-diffusion, immobility, immuno-electrophoresis, using as normal plasma as purified kallikrein. The protein 125 I-kallikrein was prepared by chloramine-t method and presented homogeneity, stability, immunoactivity and high specific activity, so that a sensitive assay was assured. 193 refs., 19 figs., 4 tabs

  1. Human growth hormone (HGH), ch. 6

    International Nuclear Information System (INIS)

    A radioimmunoassay method for the human growth hormone (HGH) is described. The requirements are discussed in detail and a scheme for the preparation of incubation mixtures is given. HGH is labelled with 125I by the chloramine T method and purified by gel filtration or electrophoresis. Separation of bound and free-labelled hormones is performed by absorption of the free hormone, using talc or charcoal

  2. Ethyl 4,4''-Difluoro-5'-hydroxy-1,1':3',1''-terphenyl-4'-carboxylate

    Directory of Open Access Journals (Sweden)

    Badiadka Narayana

    2011-11-01

    Full Text Available A simple and novel route for the synthesis of new terphenyl derivative as well as oxidative aromatization of α,β-unsaturated cyclohexenone to the corresponding phenol derivative is developed. The present work involves the condensation of ethylacetoacetate with 4,4'-difluoro chalcone followed by the aromatization using chloramine-T in acetic acid to yield the title compound (3. The synthesized compound (3 is well characterized by IR, NMR, LCMS and elemental analysis.

  3. Ethyl 4,4''-Difluoro-5'-hydroxy-1,1':3',1''-terphenyl-4'-carboxylate

    OpenAIRE

    Badiadka Narayana; Balladka Kunhanna Sarojini; Seranthimata Samshuddin

    2011-01-01

    A simple and novel route for the synthesis of new terphenyl derivative as well as oxidative aromatization of α,β-unsaturated cyclohexenone to the corresponding phenol derivative is developed. The present work involves the condensation of ethylacetoacetate with 4,4'-difluoro chalcone followed by the aromatization using chloramine-T in acetic acid to yield the title compound (3). The synthesized compound (3) is well characterized by IR, NMR, LCMS and elemental analysis.

  4. New aquaculture drugs under FDA review

    Science.gov (United States)

    Bowker, James D.; Gaikowski, Mark P.

    2012-01-01

    Only eight active pharmaceutical ingredients available in 18 drug products have been approved by the U.S. Food and Drug Administration for use in aquaculture. The approval process can be lengthy and expensive, but several new drugs and label claims are under review. Progress has been made on approvals for Halamid (chloramine-T), Aquaflor (florfenicol) and 35% PeroxAid (hydrogen peroxide) as therapeutic drugs. Data are also being generated for AQUI-S 20E, a fish sedative.

  5. Synthetic heparinoids labelled with 125I and 35S

    OpenAIRE

    Sederel, L.C.; Kolar, Z.; Does, van der, Leen; Bantjes, A.

    1982-01-01

    The labelling of a water-soluble synthetic polyelectrolyte, having anticoagulant activity, has been studied. The polyelectrolyte is derived from cis-1,4-polyisoprene and contains N-sulfate and carboxylate groups. [125I]-Iodination of the polyelectrolyte, using the Chloramine-T method and an electrolytic method, resulted in a [125I]-labelled polyelectrolyte from which release of the label occurred. Resulfation of a partially desulfated polyelectrolyte with a [35S]-sulfur trioxide trimethylamin...

  6. Comparison and evaluation of different methods for α-MSH labelling

    International Nuclear Information System (INIS)

    The authors have studied the behaviour of 125I-labelled α-MSH under different experimental conditions. Until now, the chloramine T method had been used by most investigators with variable results. They have tested three other labelling techniques based on 125I mild oxidation: (1) an enzymatic method with lactoperoxidase, (2) a sparingly soluble chloramine method (T.D.G.U.), and (3) modified chloramine T procedure, 'the iodine volatilization method'. Labelled hormone obtained after each kind of iodination was assayed for immunoreactivity. In addition, time course degradation was measured by classical RIA incubation procedures. Charcoal-dextran was used to separate bound and free antigen. The authors have found chloramine T-iodinated α-MSH to be significantly more damaged than preparations obtained by other methods and to be less stable when stored at -180C. No differences were found between the differently labelled 125I-labelled α-MSH fresh preparations in binding to surface receptors of human melanoma cell lines in culture. (Auth.)

  7. Pituitary human growth hormone: small-scale purification method and application to radioimmunoassay

    International Nuclear Information System (INIS)

    Human growth hormone (hGH) extracted from pituitary glands is often heterogeneous, presenting, besides the native isohormone - B (IH-B) up to four different isohormones. To obtain more homogeneous preparations, essential for reproduceble radioligand assay results, the original method was modified, on a small scale, and by adding bacteriostatic and enzime inhibiting agents to all buffers (NaN3, EDTA, Trasylol) in order to minimize isohormone formation. After 3 to 4 homogeneizations and extractions of the frozen glands (10-20), hGH is precipitated, by 50% ammonium sulphate immediatly purified by Sephadex G 100 molecular sieve chromatography and hGH fractions are lyophilized. The whole process is completed in one week. Using 20 hypophises, 1.3 mg/gland was obtained. Several labellings with 125-I were performed using this purified hGH stored for more than one year. Two labelling techniques were employed: the classical method which uses 50 μg of Chloramine T and the stoichiometric iodination, which uses limiting amounts of chloramine T. For this preparation only 1.5 μg Chloramine T were necessary to achieve the desired specific activity. (author)

  8. The distribution and excretion of nerve growth factor in mice

    International Nuclear Information System (INIS)

    Nerve growth factor (NGF) was iodolabelled with chloramine-T method and its distribution and excretion in mice were investigated. The results showed that the highest levels were found in superior cervical ganglia, thyroid, bile, kidneys and adrenals between 20-30 min after injection, and the peak time in most tissues was also found at 20-30 min. About 72.55% of the injected dose was excreted in stool and urine, among them 65.6% was excreted in urine and only 7.0% in stool within 72 h after intramuscular injection

  9. Radioiodination of the protein complex of the VA-MENGOC-BC vaccine

    International Nuclear Information System (INIS)

    In this work was made the labelling of the protein complex of the vaccine VA-MEMGOC-BC with I-125 in order to study its immunological responses. These proteins were in both forms: dissolved and conjugated with polisacarids of the C-group. There were used three methods of iodination: chloramine-T iodogen and lactoperoxidase. Was found out that dissolved proteins can be iodinated using these methods with 0,1 mCi of I-125, and the obtained specific activities were similar

  10. Studies on the Radioimmunoassay of Human Growth Hormone - 1. Evaluation of the method of determination

    International Nuclear Information System (INIS)

    Utilizing the commercial radioimmunoassay kit, the author assayed HGH and evaluated the problems of the method. The method had the sensitivity of 0.5 mug/ml degree and could determine the plasma HGH concentration directly without the help of plasma extraction. Also it was specific for the HGH, when tested by a dilution method using test utilizing the plasma of the acromegalic patient. The author also obtained the 125I labelled HGH of specific activity of 156. 3 μCi/μg, performing the chloramine-T method.

  11. The tritium kinetic isotope effect for the iodination of L-(5-3H) -3-iodotyrosine

    International Nuclear Information System (INIS)

    The kinetic tritium isotope effect k(subH)/k(subT) for the iodination of L-(5-3H)-3-iodotyrosine at pH 7.5 was found to be 4.29 +-0.25 with molecular iodine and 4.50 +- 0.26 with chloramine-T/potassium iodide. This effect establishes that the rate-limiting step is proton removal by the general base. A novel method for measuring the fraction of tritiated water by high performance liquid chromatography is described

  12. Comparison of 131I-TYR3-octreotate and 131I-DOTA-TYR3-octreotate: The effect of DOTA on pharmacokinetics and stability

    International Nuclear Information System (INIS)

    The authors compared the biodistribution, and in vivo and in vitro stabilities of 131I-Tyr3-octreotate and 131I-DOTA-Tyr3-octreotate. The peptides were radioiodinated by the chloramine T method and high radiochemical yields were obtained (greater than 97%). Both labelled compounds showed high stability when incubated in human plasma at 37 deg C. The 131I-Tyr3-octreotate showed significant hepatic uptake and biliary excretion. The biodistribution of 131I-DOTA-Tyr3-octreotate, however, can be compared with the distribution of radiometal labelled octreotide analogues. (author)

  13. Qualitative and quantitative evaluation of donkeys responses to immunization by rabbits' IgG

    International Nuclear Information System (INIS)

    In this study two apparently healthy donkeys were immunized with highly pure rabbit's 1gG using a revised protocol. Qualitative test using the same immuno gen was done as a primary test to eva lute the immune system response. However, the same 1gG was iodinated with 125I using chloramine T method and the labeled 1gG was used to quantitatively study the immune response. The two donkeys showed good response with the younger one having the best response. The obtained donkey anti rabbit sera was used as separating agent for RIA assay for human PRL. (Author)

  14. optimization of insulin radioreceptor assay in human erythrocytes in normal and some disease status

    International Nuclear Information System (INIS)

    This study is concerned with the evaluation of a new optimized technique for the principle of chloramine-T method used for insulin iodination by 125I-radioisotope with some modifications. The modified procedure can be carried out under normal condition of room temperature, employed longer reaction times and omitted the addition of inorganic reducing salts, maintaining efficient iodination and avoiding denaturations to obtain labels of exceedingly high specific activity on a small quantities of insulin for in vitro usage in the investigation of human erythrocytes 125 I-insulin binding capacity in normal and some disease status

  15. Gradient polyacrylamide electrophoretic analysis of radioiodinated proteins from synaptosomes and mitochondria

    International Nuclear Information System (INIS)

    Fractions enriched in synaptosomes or mitochondria from swine brain, and mitochondria from beef heart were 125I-iodinated using either lactoperoxidase (LP) or chloramine= T catalysis. The labelled proteins were analysed by radioautography after high resolution gradient polyacrylamide gel electrophoresis. More radiolabelled protein bands were found in the brain mitochondrial fraction than in the synaptosomal fraction after LP catalysed iodination, but the protein labelling patterns of the brain organelles were similar. Comparison of the results of the two labelling procedures cannot therefore be used for the unambiguous determination of the topographic organization of the proteins in synaptic membranes. (U.K.)

  16. Preparation of iodine-123 labeled AM251: a potential SPECT radioligand for the brain cannabinoid CB1 receptor

    International Nuclear Information System (INIS)

    We report the synthesis and labeling with iodine-123 of N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251). This compound is an analog of the recently described cannabinoid receptor antagonist, SR141716A, in which a 4-chlorophenyl group is replaced by 4-iodophenyl. Labeling in good yield (62%) and radiochemical purity (> 95%), and high specific activity (> 2500 Ci/mmol) was achieved by an iododestannylation reaction using the tributyltin precursor, no carrier added I-123 iodide, and chloramine-T. (author)

  17. Radioimmunological determination of procollagen (type III) and procollagen peptide (type III)

    International Nuclear Information System (INIS)

    The detection of antigens circulating in the blood enables the early recognition of fibrotic processes e.g. liver cirrhosis and hepatitis. One thus uses an anti procollagen (type III) labelled with iodine 125 by the chloramine-T method, or an anti-procollagen peptide (type III) serum which is brought together with a sample of unknown contents. The separation of the antigen-antibody complex is carried out by means of a highly specific antiserum. The procollagen peptide (type III) is produced from calf skin of a foetus or from human aszites fluid. (DG)

  18. Radioiodinated iodophenyl maleimide: A potential radioimmunoconjugate with low in vivo deiodination

    International Nuclear Information System (INIS)

    The conceptual design and feasibility of a new sulfhydryl radiolabeled agent, N-(4-[125I]iodophenyl)maleimide, as a potential radioimmunoconjugate is described. The distribution of bovine serum albumin when labeled with 131I by the chloramine-T oxidation procedure or with 125I by maleimide conjugation was studied in normal female Fischer rats. The 125I-iodophenylmaleimide labeled bovine serum albumin showed significantly lower thyroid uptake (1.03% injected dose) and hence greater stability than the 131I labeled bovine serum albumin (4.85% injected dose) at 24 h. This promising result indicates need for further evaluation of iodophenylmaleimide as a potential radioimmunoconjugate. (orig.)

  19. Methods for labelling triiodo thyroxin (T3) and L-thyroxin (T4) with I-125 used in radioimmunoassay

    International Nuclear Information System (INIS)

    A rapid and sensitive radioimmunoassay has been developed for the measurement of T3 and T4 in human serum. This method is particularly useful for evaluating hyperthyroidism and hypothyroidism in patient with thyroid disease. T3 and T4 has been labelled with I-125 using chloramin-T method to attain tracers with specific activity 2500-3000μCi/μg. Iodinated products have radiochemical purity more than 98% (by paper electrophoresis of purified pooled fraction), immunoreactivity above 70%, non specific binding (NSB) less than 10%, used as tracer in RIA. (author)

  20. The experience with setting-up radioimmunoassay for alpha-1 fetoprotein

    International Nuclear Information System (INIS)

    The decisive factor in the preparation of radioimmunological alpha-1-fetoprotein determination, provided sufficient commercial or own antisera and standards are available for calibration, is the quality of the preparation for labelling. Alpha-1-fetoprotein was separated by affinity chromatography using Sepharose with alpha-1-fetoprotein-bound antibodies. The isolates thus obtained were labelled with 125I using enzyme and chloramine T and Iodogen techniques. The labelled alpha-1-fetoprotein can be used for RIA. In view of reduced immunoreactivity of the preparation, however, the performance of the radioimmunological determination has so far not matched the quality of imported kits. The technique is currently being optimized. (author)

  1. Preparation of iodine-123 labeled AM251: a potential SPECT radioligand for the brain cannabinoid CB1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Ruoxi; Makriyannis, Alexandros [Connecticut Univ., Molecular and Cell Biology Dept., Storrs, CT (United States); Gatley, S.J. [Brookhaven National Lab., Medical Dept., Upton, NY (United States)

    1996-10-01

    We report the synthesis and labeling with iodine-123 of N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251). This compound is an analog of the recently described cannabinoid receptor antagonist, SR141716A, in which a 4-chlorophenyl group is replaced by 4-iodophenyl. Labeling in good yield (62%) and radiochemical purity (> 95%), and high specific activity (> 2500 Ci/mmol) was achieved by an iododestannylation reaction using the tributyltin precursor, no carrier added I-123 iodide, and chloramine-T. (author).

  2. Fungicidal effect of 15 disinfectants against 24 fungal contaminants commonly found in bread and cheese manufacturing

    DEFF Research Database (Denmark)

    Bundgaard-Nielsen, Kirsten; Nielsen, Per Væggemose

    1996-01-01

    Resistance of 19 mold- and 6 yeast- species against 15 commercial disinfectants was investigated by a suspension-method in which the fungicidal effect and germination time were determined at 20 °C. Disinfectants containing 0.5 % dodecyldiethylentriaminacetic acid, 10 g/l chloramine-T, 2....... The examined isolates of P. roqueforti var. carneum, P. discolor, Aspergillus versicolor and Eurotium repens were resistant to different quaternary ammonium compounds. Conidia and vegetative cells were killed by alcohols, whereas ascospores were resistant. Resistance of ascospore to 70% ethanol...

  3. Isolation of a somatomedin binding protein from human preterm amniotic fluid: development of a radioimmunoassay

    International Nuclear Information System (INIS)

    This thesis investigates the nature and biological behaviour of a somatomedin binding protein, identified in preterm amniotic fluid (AF). For that purpose a double antibody radioimmunoassay was developed. Purified AF binding protein (AFBP) was iodinated by the chloramine-T method, and dilutions of partially purified AFBP were designated as the standard, with the results expressed in μg equivalent protein/ml. The sensitivity of the assay was improved by adoption of the nonequilibrium procedure. AFBP values were twice as high in preterm AF as in term AF. (Auth.)

  4. Preparation of stable 125I cyclic GMP tyrosine methyl ester suitable for 3',5' cyclic GMP radioimmunoassay by HPLC

    International Nuclear Information System (INIS)

    Determination of the concentration of cyclic guanosine monophosphate (cGMP) by radioimmunoassay (RIA) depends upon the availability of suitable radiolabeled tracers and antibody to detect the product. Reverse phase chromatographic techniques can easily separate the reaction products of chloramine-T iodination of succinyl cGMP tyrosine methyl ester. The binding characteristics of the iodination reaction products to anti-cGMP antibody have been determined. Purified succinyl cyclic nucleotide 125I-tyrosine methyl ester binds to cGMP antisera identically as commercially available tracer. The tracer is stable for greater than three months

  5. Preparation of 125I-labelled thyroid hormones for use in radioimmunoassay. Part of a coordinated programme on quality control of techniques in-vitro assay of thyroid-related hormones (Latin America)

    International Nuclear Information System (INIS)

    The primary objective was to prepare 125I labelled thyroid hormones for use in radioimmunoassays. T4 and T3 of very high specific activity was obtained by just labelling T2. With a molar relation of T2:125I as 1:2 and Chloramine T:125I as 60:1 it was possible to produce T4125I of approximately 3,300 to 3,800 uc/ug and T3125I of 1,800 and 2,500 uc/ug with reaction times of 60'' to 90''. Simultaneous production from T2 of both labelled T4 and T3 of high specific activity appears to be the best choice for routine radioimmunoassays. Various permutations of the molar relations between T2 and 125I and between chloramine T and 125I it was possible to produce labelled T3 and T4 of varying degrees of specificities. The labelled products can be separated by sephadex G25 chromatography with good resolution. The separation is still improved if sephadex LH-20 is used. T4 and T3 of very high specific activity is preserved best for about a month in Cyst-PG-Alb. Low specific activity material can be preserved in the same medium for about 3 months

  6. Immunoradiometric assay (IRMA) for hTSH - anti -hTSH monoclonal antibody (MAb) radioiodination

    International Nuclear Information System (INIS)

    Thyroid-stimulating hormone (TSH) is a glycoprotein secreted by pituitary gland and has a specific site of action which is the thyroid gland. Its main function is to regulate the release of thyroxine (T4) and of triiodothyronine (T3) and to control different stages of their synthesis. The test of measuring TSH levels is a screening test for the diagnosis of thyroid disease. An IRMA - TSH procedure was developed in order to determine the concentration of TSH in human serum samples. Two antibodies are involved in this assay system, one of which is 125 I radiolabelled. The aim of this work is to report the method of monoclonal antibody TSH 125 I radioiodination. Anti - TSH monoclonal antibody obtained from Medix Biochemica Finland was labelled by the Chloramine T method, using 10 mg of Chloramine T and 1 mCi of 125 I; the reaction time was 1 minute and the reaction was stopped by addition of 20 mg of sodium metabisulphite. Purification of radioiodinated anti - TSH monoclonal antibody was performed on a Sephadex G - 150 column, using for elution 0.05 M phosphate buffer. The studies in order to produce a IRMA -TSH kit are in progress. (authors)

  7. Preparation of 131I-epidepride and biodistribution study in SD rats

    International Nuclear Information System (INIS)

    The purpose is to study the preparation and biodistribution in animals of dopamine D2 receptor ligand 131I-epidepride. Epidepride was 131I radioiodinated with hydroperoxide or chloramine-T method. The purity and stability of 131I-epidepride were studied by HPLC and TLC, the dynamic distribution in brain and critical organs of SD rats were studied. The radiolabelling yields of 131I-epidepride were 97.4% and 52.9% respectively. With no more purification, the hydroperoxide method is better than the chloramine-T method. After 4 hours in room temperature, the radiochemical purity of 131I-epidepride was still over 90%. The striatum uptake was good, the striatum/cerebellum ratio reached 237:1 at 320 min. Among the critical organs, lung had the first and the highest uptake. All organs had quick clearance (T1/2131I-epidepride has a high striatum uptake and a high striatum/cerebellum ratio. 131I-epidepride is a good dopamine D2 receptor agent

  8. Optimization of the preparation conditions of radioiodoepidepride. A dopamine D2receptor antagonist radioligand

    International Nuclear Information System (INIS)

    [125I]iodepidepride, (s)-(-)-[(1-ethyl-2-pyrrolidinyl)methyl]-5-[125I]-iodo-2,3- dimethoxybenzamide is the iodine substituted analogue of isoremoxipride, both of which are very potent dopamine D2-antagonists. Epidepride was radioiodinated using different oxidizing agents such as chloramine-T, iodogen, iodogen glass frit and hydrogen peroxide. Chloramine-T is a powerful oxidizing agent compared to both iodogen and hydrogen peroxide so that the side products, especially the chlorinated epidepride, decreases the radiochemical yield. This chlorinated epidepride is minimized in the case of iodogen and iodogen glass frit and are not observed in case of the non-chlorinated oxidizing agent hydrogen peroxide. TLC and HPLC were used to analyze the reaction components and to estimate both the radiochemical yield and purity. The reaction parameters such as reaction time, pH, epidepride and oxidizing agent concentrations and the stabilty of the final product were studied to optimize the radiochemical yield and purity. The optimized radiochemical yield was about 90% and the radiochemical purity of the final product was 99.9%. (author)

  9. Studies on human proinsulin.C-peptide radioimmunoassay method

    International Nuclear Information System (INIS)

    125I-labelled human.C-peptide was prepared by the chloramin T method, the enzymic method and the active ester method, respectively. Using respective 125I-labelled human.C-peptides in human proinsulin.C-peptide RIA, we compared the binding (B0/T %) to antibody, displacement by standard human.C-peptide, recovery, and stability. The usable 125I-labelled antigen for human proinsulin.C-peptide RIA could be prepared by the chloramin T method and the enzymic method which labelled 125I to tyrosyl human proinsulin connecting peptide, and by an active ester method which conjugates 125I-labelled active ester to human proinsulin connecting peptide. No differences among those 125I-labelled antigens were observed in displacement (B/B0 %) by standard human.C-peptide or the recovery test. In the case of constant preparation of 125I-labelled antigen for RIA, the enzymic method was the best from the viewpoint that reaction ratio is stable and the stability of B0/T % was good. (auth.)

  10. The In vitro Inhibitory Effects of Some Disinfectants on Enzyme Activity of Carbonic Anhydrase from Rainbow Trout (Oncorhynchus Mykiss Gills

    Directory of Open Access Journals (Sweden)

    ??kriye Aras Hisar

    2005-01-01

    Full Text Available Traditional treatments of parasitic and bacterial disease in aquaculture are based on chemotherapeutic compounds. Although, a lot of compounds are used on fish treatment, their undesirable effects are not known in detail. In this study, the effects of some disinfectants - malachite green, methylene blue, potassium permanganate, chloramine-T, copper sulphate and formalin - on Rainbow Trout (RT gill Carbonic Anhydrase (CA which plays a key role in gas exchange, acid-base balance, osmoregulation and ionoregulation were investigated in vitro. For this purpose, CA was purified from RT gills by using sepharose-4$-L tyrosine-sulfanylamide affinity gel chromatography method at initial. CA enzyme with 55.56 (EU/mg proteins specific activity was purified with a yield of 40 % and 104.8-fold finally. I (inhibition values of malachite green, 50 methylene blue, potassium permanganate, chloramine-T and copper sulphate were determined as 0.05 mM, 0.023 mM, 0.15 mM, 0.32 mM and 5.39nM by means of activity % [disinfectant] graphs, respectively. In conclusion our data showed that all the disinfectants except formalin had the in vitro inhibitory effects on the rainbow trout gill CA enzyme whose inhibition could be hazardous to physiological functions such as osmoregulation and acid-base balance in fish.

  11. Study on novel peptide probe 131I-RRL for tumor molecular imaging

    International Nuclear Information System (INIS)

    To study the potential application value of Ary-Ary-Leu(RRL) specially combined with tumor derived endothelial cells in tumor molecular imaging for melanoma bearing mice, a novel peptide RRL was designed and labeled with 131I by chloramine-T method, and mice bearing melanoma tumor were injected 131I-RRL to imaging. The labeling results showed that the optimized condition were following: 50 μg RRL, 10 μL (74 MBq) Na 131I, 90 μg chloramine-T, total reaction volume 100 μL, and reaction time 3 min, the labeling yield was over 69%. The labeling compound was purified by Sephadex G25, its radiochemical purity was > 95%. In vitro binding experiments, FITC-RRL was mainly combine with tumor cells and tumor angiogenesis endothelial cells, and in the SPECT imaging, 131I-RRL peptide could successfully image the tumor in nude mice bearing melanoma tumor for 24 h after injection. The results indicated that small molecular peptide RRL was a promising carrier for tumor molecular imaging and radioimmunotherapy. (authors)

  12. Radioiodine labelling of insulin using dimethylsulfoxide as a labelling-aid

    International Nuclear Information System (INIS)

    Using dimethylsulfoxide (DMSO) as a labelling aid, insulin 126I of radioimmunoassay use has been effectively prepared. A small amount of DMSO was added to usual labelling mixture and the reaction time was controlled. The labelled insulin obtained in such a way showed improved bindabilities to the antibody and thus expressed larger dose-gradients in the plots of standard dose-response curves even though the labelling rate was decreased to some extent. However, by extending the reaction time to about 1 min, average labelling yield of 30% could be obtained. The average increase of bindability (B/F) in definite antiserum dilution was 2.5 comparing with 1.5 obtained in the absence of DMSO. Thus, the net bindability increase was 70% of those obtained in the absence of DMSO. By means of NMR spectrometry, it has been confirmed that the DMSO in the labelling mixture is converted to dimethylsulfone by chloramine-T. The results, generally agreed with the Stagg's postulation, were discussed in view of a competitive oxidation of DMSO with disulfide linkages of the insulin molecule by the chloramine-T. (author)

  13. Radioiodination and biological evaluation of levalbuterol as a new selective radiotracer. A β{sub 2}-adrenoceptor agonist

    Energy Technology Data Exchange (ETDEWEB)

    Sanad, Mahmoud Hamdi; Abelrahman, Mohamed Abdelmotelb; Marzook, Fawzy Mohamed Abdelmaged [Atomic Energy Authority, Cairo (Egypt). Radioisotopes Production and Radioactive Sources Div.

    2016-08-01

    Levalbuterol was successfully radiolabeled with iodine using chloramine-T as an oxidizing agent via an electrophilic substitution reaction. The reaction parameters that affecting the labeling yield such as levalbuterol concentration, chloramine-T concentration, pH of the reaction medium and reaction time were studied in details. The radiochemical yield was 97.5 ± 0.5% and the radioiodinated compound was separated by HPLC. In vitro studies showed that the iodinated levalbuterol was stable for up to 24 h. The biodistribution in experimental animals showed that the lung uptake was 68.18 ± 0.17% at 5 min post injection which decreased with time until reached to 18.7 ± 0.12% at 2 h which was higher than other recent developed radiopharmaceuticals for lung imaging. The clearance pathways from the mice appear to proceed via both hepatobiliary and renal pathways. Predosing the mice with cold levalbuterol reduced the lung uptake to 20 ± 1.3% and further confirms the high specificity and selectivity of {sup 125}I-levalbuterol for the lung.

  14. Labeling Lanreotide with 125I and 188Re

    International Nuclear Information System (INIS)

    Lanreotide is a new somatostatin analogue. It can bind to human somatostatin receptor (hSSTR) subtype 2 through 5 with high affinity and to hSSTR subtype I with low affinity. We investigate labeling condition, quality control and stability in vitro of 125I-Lanreotide and 188Re-lanreotide respectively. (A) Lanreotide is labeled with 125I using Chloramine T. The effect of reaction condition (such as reaction time, pH value, Lanreotide amount, quantity of Chloramine T and reaction volume) on labeling yield is investigated in detail. (B) The labeling yield and radiochemical purity (RP) is measured with paper chromatography (PC) and Sep-Pak C18 Cartridge. (C) The stability of 125I-Lanreotide in vitro is investigated by labeling compound incubating for 48 hours at 37 deg C in the 0.9% sodium chloride solution and RP is tested by PC at specific time intervals. (D) Lanreotide is labeled directly with 188Re via the mixture of citrate and tartate using stannous chloride as reduced agent. The influence of reaction conditions such as pH, temperature, amount of stannous chloride, amount of Lanreotide and reaction time on labeling yield is investigated in detail. At the time, the stability in vitro quality control and animal test are evaluated

  15. Labelling and quality control of somatostatin analogues with 99mTc

    International Nuclear Information System (INIS)

    Techniques and methodologies for labelling peptides with 99mTc and methods for their purification, chemical, radiochemical and biological controls were evaluated. With the purpose of gaining experience, labelling with 125I was also studied. RC-160 was labelled with 125I using iodogen as well as chloramine-T method. Higher yields were obtained with chloramine-T method (60%), rendering 125I-peptide with 98% of radiochemical purity, with specific activity of 240 μCi/μg - 274 μCi/μg. The product was stable for five weeks (at -20 deg. C). For somatostatin receptors studies rat brain cortex membrane was prepared. Maximum binding capacity was 24.7% and Kaff for the binding of RC-160 to receptor was estimated as 2.0x1010 M-1. Other peptides as β-(2-Naphthyl)-DAla-Cys-Tyr-DTrp-Lys-Val-Cys-Thr amide (N-9642, Σ) and mouse epidermal growth factor (mEGF) were also labelled by means of limiting chloramine-T method. In case of mEGF the availability of membrane receptors allowed us to experiment in mice as well as in vitro. The reaction yields were up to 60% and 70% respectively. Biodistribution of 125I-mEGF in a mouse with adenoma demonstrated preferential uptake in tumour (21,7% injected dose). The radioimmunoassay system gave 39% maximum binding (MB) and 50% displacement (ED50) for 10 ng/mL unlabelled mEGF. Direct method and BFC's for labelling peptides with 99mTc were investigated and purification and quality controls studies were performed by TLC, HPLC (UV and gamma detection). RC-160 was labelled by a direct method using sodium dithionite as reducing agent with radiochemical purity >95%. The product was stable up to six hours (at RT). Considerable adsorption problems were observed. Biological behavior was in accordance with the compounds' lipophilicity. The synthesis of TOC conjugates with HYNIC as BFC was done with 45%±5% (n=3) yield. Labelling of HYNIC-TOC with tricine as co-ligand was conducted with up to 90% yield. Studies of RC-160 labelling using 99m

  16. Separation of sup 125 I-labelled triiodothyronine (T3) and thyroxine (T4) on a sephadex G25 column with the elution of sodium hydroxide buffer

    International Nuclear Information System (INIS)

    Radioiodine labelled triiodothyronine and thyroxine hormones were obtained by iodinating T3 with NaI sup 125 by using chloramine-T method. sup 125 I-T3 and sup 125 I- T4 separated on a sephadex gel G25 filtration column eluted with 0.015 M NaOH, pH 12.0 or 0.05M NaHCO sub 3, pH 9.0 buffer. The percentage of radioiodine incorporated to T3 was 40-60% and to T4 between 25-40% The separation of sup 125 I-T3 and sup 125 I-T4 were completed within 5 hours following elution with NaOH buffer whereas the separation using carbonate buffer required about 12 hours. The radiolabelled T3 and T4 eluted with NaOH buffer bound to the anti T3 and anti T4 antibodies

  17. Homologous radioimmunoassay of human prolactin

    International Nuclear Information System (INIS)

    Gelfiltration on Sephadex G-75 showed a heterogenity of prolactin in serum of patients with prolactinoma and in culture medium of a prolactinoma. Serum of patients with prolactinoma and culture medium of a prolactinoma were examined as possible sources of prolactin by gel filtration and ion exchange chromatography. Polyacrylamide electrophoresis revealed both preparations as contaminated by other proteins. Nevertheless prolactin isolated form culture medium of a prolactinoma is good enough as a tracer in our radioimmunoassay because contaminating proteins in this preparation do not inferfere in our system. An hPRL antiserum created in a rabbit against a crude fraction of human serum of a patient with prolactinoma was tested by titration, saturation studies, and ion exchange chromatography. In comparison with lactoperoxidase-iodinated prolactin Chloramine T iodinated prolactin showed higher loss of immunochemical properity, however higher specific activity. Specifity and precision in our radioimmunoassay system were described and the conditions of optimal sensitivity in our assay were evaluated. (orig.)

  18. Rapid method for the preparation of 125I-labelled human growth hormone for receptor studies, using reverse-phase high performance liquid chromatography

    International Nuclear Information System (INIS)

    Human growth hormone was labelled with 125 Iodine by the stoichiometric modification of the chloramine-T method to a specific activity of 50-80 microCi/microgram, and the iodinated mixture was purified by reverse-phase high performance liquid chromatography using a C18 column (SynChropak RP-P) and a linear gradient. Compared with the usual Sephadex G-100 chromatography, HPLC gave a much better separation, with a higher yield and a considerably reduced analysis time (30 min vs 5 h). The [125I]-labelled preparation had normal binding to IM-9 lymphocyte receptors. The maximum bindability of the HPLC-purified preparation approximated 90%, which is the best value so far reported for human growth hormone. It is concluded that HPLC is a fast, convenient and reproducible method for obtaining an improved [125I]-labelled human growth hormone for receptor studies

  19. Development of the kits for RIA simultaneous determination of polypeptide hormones

    International Nuclear Information System (INIS)

    A simple and universal modification of chloramine T technique has been developed for the radioactive iodination of several polypeptide hormones such as insulin, human growth hormone (HGH), human TSH, synthetic human gastrin and beta-endorphine. The prepared products proved to have good immunoreactivity suitable for RIA purposes. The technique is inexpensive and quick. A new procedure has also been worked out utilizing horse myeloperoxidase in solid state as catalyser. The hormones iodinated with this technique show better parameters (e.g. longer stability, better binding to antibody, more favourable adsorption on dextran-coated charcoal); however the specific activities achieved were lower. The possibilities of simultaneous measurement of insulin and HGH have been studied. In this connection, a comparatively simple method for the determination of the endogenous anti-insulin antibodies was developed and used for the control of patients with diabetes and for the checking of new insulin preparations. However, the technique requires relatively sophisticated equipment and computerized calculations

  20. Immunoradiometric assay for human thyrotropin (h-TSH) monoclonal antibody radioiodination

    International Nuclear Information System (INIS)

    125 I labelled monoclonal antibody (MAb) TSH was prepared to be used for determination of h-TSH in clinical assay laboratory by an immunoradiometric assay (IRMA). Determination of h-TSH by this method helps to confirm the diagnosis of thyroid toxic adenoma or hypophysis tumours. In this study, the preparation and characterization of this reagent is described. The radioiodination of monoclonal antibody TSH was carried out by chloramine T method and the reaction mixture was purified by chromatography on a Sephadex G150 column. The reaction yields were around 80 % and 125 I - MAb anti h-TSH has the following characteristics: specific activity = 20-24 μCi μg and radioactive concentration ≅ 25 μCi/ml. Also, the immunological properties of the tracer were verified. 125 I labelled monoclonal antibody anti h-TSH will be used as reagent for direct immunometric assay of h-TSH. (authors)

  1. Synthesis of 131I labeled diiodothyronine (131I-T2)

    International Nuclear Information System (INIS)

    Objective: To synthesise 131I-T2 as the basis for future synthesis of 131I-T2S with sulfation. Methods: Firstly 3-T1 was radiolabeled with 131I with chloramine-T(Ch-T) labeling method. Then gel column chromatography and paper chromatography were used for separation and purification. Measurement of the labeling efficiency, radiochemical purity,stability of labeled compound, and identification of the product of immune activity were carried out. Results: The radiolabeling yield of the labeled compound produced with the modified Ch-T method was about 65.1%±4.5% (n=5) and the radiochemical purity was about 96.5%±1.1% (n=5). After 10d storage at -20 degree C, the radiochemical purity of the product still remained above 90%. Conclusion: High rate of labeling efficiency and good stability could be obtained with Ch-T labeling method. (authors)

  2. Feasibility of iodine-125 labeled anti-human hemoglobin antibody in the detection of bleeding sites from the large bowel-A preliminary study

    International Nuclear Information System (INIS)

    A monoclonal anti-human hemoglobin antibody that cross-reacts with mouse hemoglobin was labeled with Iodine-125 through the Chloramine-T method. The labeled antibody was used in an attempt to recognize bleeding sites from the large bowel in a mouse model, through a non-invasive enema-like study. In vitro experiments after double column chromatography of the labeled antibody and 10% trichloroacetic acid conjugation revealed that about 80% of the radioactivity was incorporated into protein. Inhibition assay containing could (non-radiolabeled) antibody showed that Iodine-125 radiolabeled antibody preserved its immunoreactivity. Autoradiographs exquisitely demonstrated accumulation of isotope in the corresponding intestinal bleeding areas. These findings suggest that this method can be useful for scintigraphic localization of bleeding sites in the large bowel. (author)

  3. UP-REGULATION OF HEPATIC RECEPTOR FOR GROWTH HORMONE IN THE FLOUNDER (PARALICHTHYS OLIVACEUS) AFTER ORAL ADMINISTRATION WITH EXOGENOUS GH

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The iodination efficiency of salmon GH(Sgh) was 38.82%,using a modification of the chloramine-T method. The specific activity of the 125I-Sgh was about 40 μCi/μg protein. The results of binding assay showed a single class of high affinity and low-capacity binding site in flounder liver. Long-term administration with exogenous GH can induce the up-regulation of hepatic GH receptor in total binding capacity though there was no significant difference of association constant among any groups. Considering that there was no significant difference in capacity of free binding sites of livers from control and experimental fish, this result also indicated that the liver from experimental fish, compared to that from control fish, had more occupied binding sites.

  4. UP-REGULATION OF HEPATIC RECEPTOR FOR GROWTH HORMONE IN THE FLOUNDER (PARALICHTHYS OLIVACEUS) AFTER ORAL ADMINISTRATION WITH EXOGENOUS GH

    Institute of Scientific and Technical Information of China (English)

    刘宗柱; 王金宝; 徐永立; 王勇; 张培军

    2001-01-01

    The iodination efficiency of salmon GH (sGH) was 38.82%,using a modification of the chloramine-T method. The specific activity of the 125I-sGH was about 40 μCi/μg protein. The results of binding assay showed a single class of high affinity and low-capacity binding site in flounder liver. Long-term administration with exogenous GH can induce the up-regulation of hepatic GH receptor in total binding capacity though there was no significant difference of association constant among any groups. Con-sidering that there was no significant difference in capacity of free binding sites of livers from control and experimental fish, this result also indicated that the liver from experimental fish, compared to that from control fish, had more occupied binding sites.

  5. Direct astatination of a tumour-binding protein, human epidermal growth factor, using nido-carborane as a prosthetic group

    International Nuclear Information System (INIS)

    A method for direct astatine labeling of proteins has been investigated. Binding sites for astatine were created by coupling of a nido-carborane derivative to a protein, the human epidermal growth factor (hEGF), using two different conjugation methods - by glutaraldehyde cross-linking or by introduction of sulfohydryl groups by Traut's reagent with subsequent linking of ANC-1 with m-maleimidobenzoyl-N-hydroxysulfosuccinimide ester. The conjugates were astatinated using the Chloramine-T method in high yield. The best labeling was obtained by the glutaraldehyde conjugate with an average yield of 68 ± 9%. In vitro stability tests indicated that the glutaraldehyde conjugated label was as stable as hEGF labeled with astatobenzoate. (author)

  6. Preparation of [123I]- and [125I]epidepride: a dopamine D-2 receptor antagonist radioligand

    International Nuclear Information System (INIS)

    (S)-(-)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-[123I] iodo-2,3-dimethoxybenzamide (TDP 517) (proposed generic name, [123I]epidepride) is the iodine-123 substituted analogue of isoremoxipride (FLB 457), both of which are very potent dopamine D-2 antagonists (epidepride KD 0.024 nM). [123I] Epidepride was radioiodinated in 60-70% radiochemical yields in 35 min from the corresponding 5-(tributyltin) derivative using Na123I with a specific radioactivity of 3000 Ci/mmol, and oxidized in situ with chloramine-T. The aryltin precursor was prepared from non-labelled epidepride by palladium-catalyzed stannylation using bis(tri-n-butyltin) in triethylamine. Alternatively, using no carrier-added Na125I as the radioisotope, [125I] epidepride at 2000 Ci/mmol specific radioactivity was prepared in 86% radiochemical yield and 99% radiochemical purity after purification by reverse phase HPLC in ethanolic phosphate buffer. (author)

  7. Development and Optimization of Sepharose Solid Phase Radioimmunoassay for Estimation of Thyroid Stimulating Hormone

    International Nuclear Information System (INIS)

    The aim of the present study was oriented to develop, optimize and validate solid phase radioimmunoassay, through many studies on Sepharose, for estimation of thyroid stimulating hormone in humane serum. Preparation of polyclonal antibodies was carried out in host rabbit animals against TSH antigen followed by partial purification of 1gG. Linkage of antibody 1gG to activated Sepharose CL-4B was carried out after activation of Sepharose with 1,1- carbonyldiimidazole. Labeling of TSH was carried out using chloramine-T as an oxidizing agent and the labeled tracer was purified through PD-10 column. Extensive studies were carried out to obtain the optimum conditions of using solid phase Sepharose to reach higher separation efficiency. The results of validation tests reveal that the local solid phase system is precise and accurate for evaluation of thyroid disorders

  8. development of solid phase anti-T3 and anti-T4 coated beads for detection of T3 and T4 hormones

    International Nuclear Information System (INIS)

    the thyroid secretes two significant hormones thyroxin and triiodothyronine, commonly called T4 and T3, respectively. both of these hormones have profound effect of increasing the metabolic rate of the body. in the present study a radioimmunoassay system was developed to detect T3 and T4 hormones. the solid phase anti-T3 and anti-T4 coated beads was prepared also the radiolabeled T3 and T4 was prepared using diiodothyronine (T2) and I125 with chloramine-T method. the system was developed and characterized according to the terms of accuracy, sensitivity, specificity, cross- reactivity and dilution effect. also the results of patient serum obtained by the developed system were compared with that of commercially used kit. from the obtained results it was found that the prepared system was closely similar to that of commercially used one

  9. Iodination of monoclonal antibodies, proteins and peptide using iodogen

    International Nuclear Information System (INIS)

    The use of the iodinating reagent 1,3,4,6-tetrachloro-3α, 6α-diphenylglycholuril (Iodogen) to label monoclonal antibodies (McAbs). Proteins and peptides was invesrigated with McAbs identified as mouse IgG and IgM, arginine-vasopressin (AVP), glucagon (Glu), human insulin(hI) and albumin(Alb). The labeled products were purified by gel chromatography and their immunoreactivity were detected by RIA or IRMA> Comparison of the Iodogen method with the lactoperoxides and chloramine-T methods showed that the Iodogen method had a number of advantages: 1) technically simpler ; 2) a high labeling efficiency could be obtained; 3) the immunoreactivity of the products was minimally affected; 4) the products were stable for up to 4 months

  10. Standardisation of radioimmunoassay for human insulin employing magnetizable cellulose particles

    International Nuclear Information System (INIS)

    We describe a convenient and flexible solid phase radioimmunoassay for human insulin employing magnetizable cellulose particles. Anti-porcine insulin antibody was covalently linked to magnetizable cellulose particles to form a stable and economical solid phase immunosorbent system. The tracer was prepared by radioiodinating insulin with 125I using Chloramine-T oxidation method. The analytical sensitivity of assay observed was 5.5 μIU/mL. Intra-assay and inter-assay variations were found to be <12 % along with analytical recovery of 93-109 %. The developed assay can be used for the routine analysis of clinical samples. In addition, concentration of the solid phase magnetizable immunosorbent can be easily varied as per the specific requirement for research purposes. (author)

  11. Preparation and Validation of Double Antibody Radioimmunoassay for Thyroglobulin (Tg) using Balb/C Mice as Host Animals

    International Nuclear Information System (INIS)

    The preparation and development of primary reagents of thyroglobulin (Tg) radioimmunoassay technique with low cost is considered to be the main objective of present study. The production of polyclonal antibodies of thyroglobulin was undertaken by immunizing three bulb/C mice intraperitoneal through primary injection and two booster doses. The preparation of 125I-Tg radiotracer was carried out using chloramine-T as oxidizing agent. The preparation of thyroglobulin standards were carried out. Optimization and validation of the assay were studied out. The results obtained provide a highly sensitive, specific and accurate RIA system for thyroglobulin based on liquid phase separation. In conclusion, this assay could be used for diagnosis of thyroid cancer.

  12. Measurement of plasma canine C peptide by radioimmunoassay

    International Nuclear Information System (INIS)

    A sensitive radioimmunoassay for canine C peptide (CCP) was established using synthetic CCP, a specific antiserum, and rabbit anti-guinea pig serum. Radioiodination was performed according to a modified chloramine T method. Tracer preparations have been used for 6 weeks after iodination. The standard curve ranges from 0.028 to 3.0 nmol/l. The intra-assay coefficient of variation (CV) was 3-5% and the inter-assay CV was 6-9% in the optimal range between 0.3 and 0.8 nmol/l. The average recovery of CCP added to plasma samples was 100.6% (n = 9). Canine insulin, porcine proinsulin, bovine proinsulin, and human C peptide exhibited no cross-reactivity. The mean fasting plasma CCP concentration was 0.089 +- 0.021 nmol/l in normal dogs and -0.005 +- 0.007 nmol/l (mean +- SEM) in diabetic dogs, respectively. (author)

  13. Standardization of human thyrotropin radioimmunoassay and its application to the purification of this hormone to the preparation of the assay reagents

    International Nuclear Information System (INIS)

    The various steps that are necessary for setting up the thyrotropin radioimmunoassay are presented below. Radioiodination was carried out through the Chloramine T method and the labeled purification performed on Sephadex G-100. Purification of human thyrotropin from side fractions obtained during the purification of growth hormone was carried out in order to obtain a pure reagent for use in the radioimmunoassay. The employment of the hormone obtained was evaluated as the radioimmunoassay tracer in comparison with that prepared from the hormone received from the NIDDKD, U.S.A. The results indicated that although it was not possible to obtain a hormone with a purity degree adequate to be used as the tracer, enough experience was acquired for the isolation of thyrotropin. (author)

  14. Development of a radioimmunoassay for pig pancreatic kallikrein

    International Nuclear Information System (INIS)

    A radioimmunoassay for the determination of pig pancreatic kallikrein was developed. The chloramine-T method was employed for the labelling of the antigen with 125I. The assay allows the determination of kallikrein in concentrations as low as 0.4 μg/l. Pig urinary and pig submandibular kallikreins are indistinguishable from pig pancreatic kallikrein by the assay. No cross reactivity was observed for bovine trypsin and chymotrypsin, porcine trypsin and kallikreins of guinea pig submandibular glands and guinea pig coagulation glands. Because of the high specificity of the assay, which is not attainable with conventional assays based on the enzymatic activity, the radioimmunoassay is highly suited for investigations into the physiological role and the pharmacological mechanism of action of pig glandular kallikreins. (orig.)

  15. Retention of biological activity following radioiodination of human interleukin 2: comparison with biosynthetically labeled growth factor in receptor binding assays

    International Nuclear Information System (INIS)

    Human interleukin 2 (IL-2) was radioiodinated by a modified form of the chloramine-T reaction. Comparison with biosynthetically radiolabeled IL-2 demonstrated that the iodinated molecule retained similar receptor binding characteristics and proliferation-inducing ability. The iodinated molecule also possessed the distinct advantages of a higher specific radioactivity and a reduced processing time for the assay samples. The majority of the iodine was incorporated at the tyrosine in position 45 of the polypeptide chain. Evidently, this residue is unimportant for the molecule's association with its receptor. The development of active radioiodinated IL-2 should facilitate routine measurement of the high-affinity IL-2 binding sites which mediate the physiological response to this lymphokine. (Auth.)

  16. 3H and 125I radioimmunoassays of haloperidol compared with fluoroimmunoassay involving antibody coupled to magnetizable solid phase

    International Nuclear Information System (INIS)

    Radioimmunoassays for haloperidol are described, involving use of tritium-or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also described in which the antiserum is coupled to magnetizable solid-phase medium, and fluorescein-labeled haloperidol is used. The assays have acceptable accuracy, precision, and reproducibility, and are specific for haloperidol and similar butyrophenones, with no significant interference from known metabolites and other drugs. Only the radioimmunoassays have sufficient sensitivity to cover the whole range of haloperidol concentrations in serum. The fluoroimmunoassay can be used to monitor high concentrations of haloperidol in 150 μL samples or the complete concentration range of 1-mL serum samples that are extracted and concentrated before assay

  17. 3H and 125I radioimmunoassays of haloperidol compared with fluoroimmunoassay involving antibody coupled to magnetizable solid phase

    International Nuclear Information System (INIS)

    Radioimmunoassays for haloperidol are described, involving use of tritium- or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also described in which the antiserum is coupled to magnetizable solid-phase medium, and fluorescein-labeled haloperidol is used. The assays have acceptable accuracy, precision, and reproducibility, and are specific for haloperidol and similar butyrophenones, with no significant interference from known metabolites and other drugs. Only the radioimmunoassays have sufficient sensitivity to cover the whole range of haloperidol concentrations in serum. The fluoroimmunoassay can be used to monitor high concentrations of haloperidol in 150-microL samples or the complete concentration range of 1-mL serum samples that are extracted and concentrated before assay

  18. Preparation of Double Antibody Radioimmunoassay for Determination of Alpha fetoprotein as a Tumor Marker using BALB/C Mice as Host Animals

    International Nuclear Information System (INIS)

    The aim of the present work was to prepare liquid phase radioimmunoassay system (RIA) reagents. Development as well as optimization and validation of this RIA system for the measurement of alpha fetoprotein (AFP) in human serum are described. The production of polyclonal antibodies was carried out by immunizing four BALB/C mice subcutaneously. The preparation of 125I-AFP tracer was performed using chloramine-T oxidation method. The preparation of AFP standards was done by diluting cord sera using assay buffer. The results obtained provide a highly sensitive,precise and accurate RIA system of AFP based on liquid phase separation. In conclusion, this assay could be used for the diagnosis and management of patients with certain malignant diseases and in prenatal diagnosis of neural tube defects

  19. Radioiodination of monoclonal antibodies, proteins and peptides for diagnosis and therapy. A review of standardized, reliable and safe procedures for clinical grade levels kBq to GBq in the Goettingen/Marburg experience

    Energy Technology Data Exchange (ETDEWEB)

    Behr, Th.M.; Gotthardt, M.; Behe, M. [Marburg Univ. (Germany). Dept. of Nuclear Medicine; Becker, W. [Goettingen Univ. (Germany). Dept. of Nuclear Medicine

    2002-04-01

    Simple and reliable methodologies for radioiodination of proteins and peptides are described. The labeling systems are easy to assemble, capable of radioiodinating any protein or, with slight modifications, also peptide (molecular mass 1000-300,000) from kBq to GBq levels of activity for use in diagnosis and/or therapy. Furthermore, the procedures are feasible in any nuclear medicine department. Gigabecquerel amounts of activity can be handled safely. The most favored iodination methodology relies on the lodogen system, a mild oxidating agent without reducing agents. Thus, protein degradation is minimized. Labeling yields are between 60 and 90%, and immunoreactivities remain {>=}85%. Other radioiodination methods (chloramine-T, Bolton-Hunter) are described and briefly discussed. (orig.)

  20. Radioiodination of monoclonal antibodies, proteins and peptides for diagnosis and therapy. A review of standardized, reliable and safe procedures for clinical grade levels kBq to GBq in the Goettingen/Marburg experience

    International Nuclear Information System (INIS)

    Simple and reliable methodologies for radioiodination of proteins and peptides are described. The labeling systems are easy to assemble, capable of radioiodinating any protein or, with slight modifications, also peptide (molecular mass 1000-300,000) from kBq to GBq levels of activity for use in diagnosis and/or therapy. Furthermore, the procedures are feasible in any nuclear medicine department. Gigabecquerel amounts of activity can be handled safely. The most favored iodination methodology relies on the lodogen system, a mild oxidating agent without reducing agents. Thus, protein degradation is minimized. Labeling yields are between 60 and 90%, and immunoreactivities remain ≥85%. Other radioiodination methods (chloramine-T, Bolton-Hunter) are described and briefly discussed. (orig.)

  1. Fetal antigen 2: an amniotic protein identified as the aminopropeptide of the alpha 1 chain of human procollagen type I

    DEFF Research Database (Denmark)

    Teisner, B; Rasmussen, H B; Højrup, P;

    1992-01-01

    Fetal antigen (FA2) was purified from second trimester human amniotic fluid by immunospecific chromatography, gel filtration and reversed-phase chromatography. Gel filtration revealed two molecular forms of FA2 eluting at volumes corresponding to an M(r) of approximately 100 kDa and 30 kDa. SDS...... aminopropeptide of the alpha 1 chain of human procollagen type I as determined by nucleotide sequences. After oxidative procedures normally employed for radio-iodination (iodogen and chloramine-T), FA2 lost its immunoreactivity. An antigen which cross-reacted with polyclonal rabbit anti-human FA2 was demonstrated...... in fetal calf serum. Gel filtration with analysis of fractions by inhibition ELISA showed that the bovine homologue was present in the same molecular forms as those in human amniotic fluid, and immunohistochemical analysis with anti-human FA2 showed that its distribution in bovine skin was identical...

  2. Receptor-purified, Bolton-Hunter radioiodinated, recombinant, human epidermal growth factor: An improved radioligand for receptor studies

    International Nuclear Information System (INIS)

    We report an assessment of the applicability of the Bolton-Hunter method to the radioiodination of epidermal growth factor (EGF). Recombinant human EGF (hEGF) could be radioiodinated successfully by this method, whereas murine EGF could not. Bolton-Hunter 125I-labeled hEGF was compared with commercial 125I-labeled hEGF prepared by the chloramine-T radioiodination method. Neither radioligand was sufficiently pure for a detailed characterization of the purportedly heterogeneous pattern of binding of EGF to its receptors. A procedure based on receptor adsorption was thus developed for repurification of the Bolton-Hunter 125I-labeled hEGF. This provided a much purer radioligand suitable for detailed studies of receptor-binding heterogeneity

  3. Evaluation of the efficacy and influence of the decontamination and sterilization of FBGs exposed to S. aureus and E. coli

    Science.gov (United States)

    Karam, Leandro Z.; Franco, Ana Paula G. O.; Tomazinho, Paulo; Signorini, Luciana; Carvalho, Lídia; Fernandes, Maria H.; Hecke, Mildred B.; Kalinowski, Hypolito J.

    2011-05-01

    The FBGs (Fibre Bragg Grating) are adequate sensors for measuring strain in biomedical applications. This work evaluates the efficacy of some products and processes, which are used for the decontamination and sterilization of these sensors. Fibre optic samples, partially stripped of the primary coating, were contaminated by E. coli and S. aureus and suffered decontamination processes by autoclave heating, immersion in ethylene oxide, sodium hypochlorite, chloramine T or peracetic acid and illumination ultra-violet radiation. After each process fibre samples were removed, washed in sterile saline and placed individually in BHI broth tubes. Tubes that showed turbidity of the BHI broth were considered positive. The sterilization practices by heating and immersionand avoided the formation of bacteria colonies, whereas illumination processes were not effective to avoid the bacteria colony growth.

  4. Preparation of 125I-protein A usable for up to 10 months in immunoassays

    International Nuclear Information System (INIS)

    Chloramine-T iodination of protein A from Staphylococcus aureus and gel electrophoretic purification of the iodination mixture results in a stable tracer of high specific and functional activity. Following repeated gel electrophoresis of the tracer only a single component was observed. The specific activity of the 125I-protein A was between 30 and 55 μCi/μg. The binding of 125I-protein A to rabbit immunoglobulin exceeded 90% and the tracer competed effectively with unlabelled protein A in binding to cells incubated with sera containing surface antibodies. Storage of the tracer for up to 46 weeks resulted in a moderate decrease in maximal binding to immunoglobulin (from 91% to 64%), in TCA precipitable radioactivity (from 97% to 80%) and an approx. 30% decrease in the ability to detect cell bound immunoglobulin. It is concluded that gel electrophoretic purification of 125I-protein A produces a tracer with a very long shelf life. (Auth.)

  5. Spectrophotometric determination of azathioprine in pharmaceutical formulations.

    Science.gov (United States)

    Lakshmi, C S; Reddy, M N

    1998-12-01

    Four simple and sensitive visible spectrophotometric methods (A-D) have been described for the assay of azathioprine (ATP) either in pure form or in pharmaceutical formulations. Methods A and B are based on the oxidation of ATP with excess N-bromosuccinimide (NBS) or chloramine-T (CAT) and determining the consumed NBS or CAT with a decrease in colour intensity of celestine blue (CB) (method A) or gallocyanine (GC) (method B), respectively. Methods C and D are based on the diazotisation of reduced azathioprine (RATP) with excess nitrous acid and estimating either the consumed nitrous acid (HNO(2)) with cresyl fast violet acetate (CFVA) (method C) or by coupling reaction of the diazonium salt formed with N-1-naphthyl ethylene diamine dihydrochloride (NED) (method D). All of the variables have been optimized and the reactions presented. The concentration measurements are reproducible within a relative standard deviation of 1.0%. Recoveries are 99.2-100.3%. PMID:18967434

  6. Pharmacodynamics of benziadarone labelled with 131-I

    International Nuclear Information System (INIS)

    Regarding the importance of benziodarone (Retrangor) - 2-ethyl-3-(3',5'-diiodo-4'-hidrovibenzoyl)benzofuran - in medical practice in respect of its vasodilator and uricosuric action, a working plan was developed intending to study the biological distribution of the drug rats Wistar and, using the plasmatic curve, to find out the existence of other compartments besides the intravascular one. With these data, the rhythms of benziodarone exchange were established, simulating its distribution in the organism. It was possible to develop this working project because the benziodarone structure could be labelled with iodine-131, using an isotopic exchange reaction, having chloramine T as an oxidant agent. The labelled compound was employed as radioactive tracer, and its specific activities varied from 18 uCi/mg to 20 uCi/mg

  7. In vitro evaluation of the disinfection efficacy on Eimeria tenella unsporulated oocysts isolated from broilers.

    Science.gov (United States)

    Guimarães, José S; Bogado, Alexey L Gomel; da Cunha, Thiago Cezar B; Garcia, João Luis

    2007-01-01

    The objective of this study was to evaluate in vitro the action of eight chemical principles by disinfection efficacy (DE) of Eimeria tenella oocysts. Disinfection efficacy was evaluated by either destruction or sporulation inhibition of the oocysts. Eight treatments were performed: T1 (Glutaraldehyde 42.5 g + Benzalkonium Chloride 7.5 g); T2 (Benzalkonium chloride + quaternary ammonium salt); T3 (formol 37% + Sodium Dodecylbenzene Sulfonate 12%); T4 (sodium hypochlorite 2%); T5 (Orthodichlorobenzene 60% + Xylene 30%); T6 (Polyoctyl polyamino ethyl glycine + Polyoxyethylene alkylphenol ether + Sodium Chloride); T7 (Chloramine T) and finally T8 (free iodine 2.25% + Phosphoric acid 15 g). The control test was carried out with distilled water (T9). The best DE were observed, respectively, in T3 (79.49%), T5 (75.60%) and T4 (65.56%) treatments. PMID:17706006

  8. Study and development of a radioimmunoassay of antidiuretic hormone sensitive at 10/sup -12/M

    Energy Technology Data Exchange (ETDEWEB)

    Caillens, H.; Rousselet, F. (Faculte des Sciences Pharmaceutiques, (France)); Paillard, F. (Hopital Tenon, Paris (France))

    1982-07-01

    A radioimmunoassay of antidiuretic hormone is described. The antiserum was obtained by immunization of rabbits with lysine vasopressin conjugated to hemocyanine. The specificity of the antibody was selective and directed against the pentapeptide ring of the vasopressin molecule: oxytocin showed no cross-reactivity at 10/sup -9/M. The labelled hormone (/sup 125/I-AVP) prepared using the chloramine-T method had a high specific activity (1860 Ci/mmol). Incubation was performed in an equilibrium system. Comparative studies of different separation methods of bounds and free /sup 125/I-AVP showed that the sensitivity and the precision of the standard curve were better using charcoal dextran. The limit of detection of the assay was 1,6 pg per ml.

  9. Invertase immobilization by adsorption on polymer microspheres studied by radioiodination technique

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Alvaro A.A. de [Universidade Federal de Itajuba, MG (Brazil). Inst. de Ciencias Exatas. Dept. de Fisica e Quimica]. E-mail: alencar@unifei.edu.br; Pontin, Luiz F. [Universidade Federal de Itajuba, MG (Brazil). Inst. de Ciencias Exatas. Dept. de Matematica e Computacao]. E-mail: pontin@unifei.edu.br; Higa, Olga Z.; Ribela, Maria Tereza C.P. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Lab. de Biologia Molecular]. E-mail: ozahiga@ipen.br; Tomotani, Ester J.; Vitolo, Michele [Sao Paulo Univ., SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Tecnologia Bioquimico-Farmaceutica]. E-mail: michenzi@usp.br

    2005-07-01

    In this paper, we report the study of the diffusion behavior of invertase onto polystyrene-divinylbenzene (PS-DVB) microspheres. To detect the surface concentration of protein adsorbed on the microspheres, the chloramine-T method was used to label invertase and has been applied to the study of protein sorption properties on the microspheres. The sorption isotherms and the diffusion coefficient (D{sub f}) were computed from experimental results and the concentration of bound invertase was determined in terms of the Fick's law. The Hill equation was applied to the data and the binding capacity of the microspheres were estimated. The results of adsorption show that the radiolabelling invertase method are efficacious at the protein surface concentration detection and can be used to investigate the enzyme immobilization by sorption properties of polymer microspheres. (author)

  10. Preparation of a 125I labelled [1,3H]imidazole: 2-n-butyl-4(5)-125I-iodo-5(4)-hydroxymethylene imidazole

    International Nuclear Information System (INIS)

    A method for the introduction of 125I in a substituted imidazole has been devised. 2-n-Butyl-4(5)-hydroxymethylene imidazole undergoes rapid and selective electrophilic substitution on the ring when treated with a halogenating agent such as, i.a., N-chlorosuccinimide. This reaction has been adapted to the preparation of 2-n-butyl-4(5)-125I-iodo-5(4)-hydroxymethylene imidazole by treatment of 2-n-butyl-4(5)-hydroxymethylene imidazole by chloramine-T in the presence of sodium iodide. The radiolabelled product purified and isolated by HPLC is obtained at a high specific activity (2200Ci/mmol) with good chemical and radiochemical yields (∼70%). (author)

  11. A radioimmunoassay for chicken avidin

    International Nuclear Information System (INIS)

    A double-antibody solid-phase radioimmunoassay for chicken avidin is reported. Avidin was labelled with 125I by the chloramine-T method. The bound and free avidin were separated with a second antibody bound to a solid matrix. In the logit-log scale the standard curve was linear from 1-2 to 100-200ng of avidin/ml. Cross-reaction of ovalbumin was less than 0.015%. Saturation of biotin-binding sites of avidin with an excess of biotin decreased radioimmunoassay values by about 15%. Recovery studies indicated that avidin can be assayed from all chicken tissues studied with radioimmunoassay, whereas the [14C]biotin/bentonite method gave poor recoveries for avidin in the liver and kidney. Radioimmunoassay and the [14C]biotin/bentonite method gave similar concentrations for oviduct avidin. (author)

  12. Clinical scale preparation and evaluation of 131I-Rituximab for Non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Radioimmunotherapy (RIT) with anti CD20 MoAb conjugated to a β- emitting radioisotope like 131I or 90Y has the added advantage of delivering radiation not only to tumor cells that bind the antibody but also due to a crossfire effect, to neighboring tumor cells inaccessible to the antibody. In order to make available an indigenous radioimmunotherapeutic agent for Non Hodgkin's Lymphoma (NHL), radioiodinated Rituximab has been prepared and evaluated at a clinical scale. Radioiodination of Rituximab was performed by the conventional Chloramine T method using 7.4 GBq Na131I in a lead shielded plant. Six batches of radioiodination were prepared and characterized by electrophoresis and HPLC to evaluate the reproducibility of the product. The product remained stable retaining the radiochemical purity > 95% upto 5 days after radioiodination. In vitro cell binding studies and biodistribution studies in normal Swiss mice have indicated the potential of this molecule as a radioimmunotherapeutic agent for NHL. (orig.)

  13. Labelling of some amino acids with radioiodine

    International Nuclear Information System (INIS)

    Some radioiodine labelled compounds which have application in nuclear medicine have been prepared. Two common techniques were employed. A comparative study on the radioiodination of the amino acids, L - tyrosine, L - a - methyl tyrosine and L-tyrosine methyl ester has been carried out by the electrophilic radioiodination technique. The blood flow reagent, antipyrine, also has been prepared by this technique using chloramine - T, iodogen and H2 O2 as oxidizing agents to generate electrophilic iodine. Radio chromatograms revealed side product impurities at long reaction times and high oxidizing agent concentrations. Comparison between the different oxidizing agents was done. Optimization of the radioiodination conditions, such as Ph of the medium, reaction time, oxidizing agent and substrate concentrations and carrier KI concentration was performed resulting in high radiochemical yields of 97% L - 3 -(131) iodotyrosine, 95% L -3-(131) iodo-a-methyl tyrosine, 88% L-3-(131) iodotyrosine methyl ester and 96% 4-(131) iodoantipyrine within short reaction times at room temperature when chloramine - T was used as oxidizing agent. Purification by high pressure liquid chromatography resulted in high radiochemically pure products suitable for medical application. Radioiodinated 3- iodotyrosine and 4- iodophenyl alanine have been prepared by the isotopic exchange technique using cuprous chloride as catalyst for the exchange reaction. The effect of solvents and the different parameters affecting the labelling yield were investigated to optimize the conditions for labelling of these compounds. Kinetic study indicated a second order reaction with an activation energy of 9.6 and 12.20 Kcal/mole for 3- iodotyrosine and 4-iodophenyl alanine respectively. Reducing agents were added to the Cu CI catalyzed reactions to improve the yield and decrease side products formation. Applying the results obtained to the radioiodination of the phenyl fatty acid 15(p-iodophenyl) pentadecanoic acid

  14. NEW ANALYTICAL METHODS AND THEIR VALIDATION FOR THE ESTIMATION OF METOPROLOL SUCCINATE IN BULK AND MARKETED FORMULATION

    Directory of Open Access Journals (Sweden)

    Viral Bechara

    2015-02-01

    Full Text Available Metoprolol succinate is cardiovascular agent. Mainly used for the treatment of hypertension, heart failure, and cardiovascular diseases. Purpose: Analytical methods are required to characterize drug substances and drug products composition during all phases of pharmaceutical development. Development of methods to achieve the final goal of ensuring the quality of drug substances and drug products must be implemented in conjunction with an understanding of the chemical behavior and physicochemical properties of the drug substance. This determination requires highly sophisticated instruments and methods like HPLC, HPTLC and Spectrophotometer. Hence there was a need for the development of newer, simple, sensitive, rapid, accurate and reproducible analytical methods for the routine estimation of metoprolol succinate in bulk and pharmaceutical dosage form. Methods: The present work describes two new spectrophotometric methods for the determination of metoprolol succinate in bulk and marketed formulations. Method A is based on oxidation reaction. Metoprolol succinate in presence of acidic medium reacts with excess amount of chloramine-T and remaining chloramine-T react with malachite green to produce orange colour chromogen which showed λmax at 516 nm. In Method B, the drug was diazotised with sodium nitrite in presence of hydrochloric acid and then it was coupled with β-naphthol in alkaline medium. Which produce red colour chromogen which showed λmax at 688 nm. Results: The linearity was found in concentration range of 5-30μg/ml for both method A and method B. The correlation coefficient was found to be 0.9983 and 0.9993 for method A and method B respectively. The methods were validated as per ICH guidelines. The LOD and LOQ for estimation of Metoprolol succinate were found as 0.0773, 0.2343 for method A and 0.0667, 0.2021 for method B respectively. Conclusion: Proposed methods were successfully applied for the quantitative estimation of

  15. Labeling of the Recombinant Streptokinase Using Iodine-131 as a New Thrombolytic Agent

    International Nuclear Information System (INIS)

    Stroke and acute myocardial infarction is a disease with the highest mortality in the world. WHO has estimated in 2008, 30% of deaths from heart disease and more than 80% of this cases have been occurred in developing countries. Streptokinase (SK) as an effective thrombolytic agent has been used as a drug of choice for about forty years ago. SK is plasminogen (PG) activator that converts plasminogen to active protease, called plasmin (PN) which degrades fibrin to soluble products. Recombinant streptokinase (SKA) from genetic engineering has been developed at School of Pharmacy ITB to reduce or eliminate immunogenicity of SK. However, scientific disclosures relating to dynamic and its kinetic studies in the body have still to be proven. One method that can explain this phenomenon is the pharmacological studies using radionuclide labeled compounds. Radioiodine labeled compound is used extensively and most suitable for biological studies. This paper describes the preparation of 131I-SKA and its characterization. The labeling conditions of SKA, such as chloramine-T as an oxidizing agent, amount of SKA, incubation time, and size of resin to purify the labeling yield have been observed. The result showed that the optimum condition of labeling (35.11%) was obtained using 10 µg of chloramine-T and 60 seconds of incubation time. The highest radiochemical purity (97.46 ± 1.14%) has also been obtained by passing through the resin chromatography column using 100 mg Dowex 1x8, size 50-100 mesh. The characterization of 131I-SKA with SDS PAGE method and autoradiography showed the similar performance with unlabeled-SKA (author)

  16. Radioiodination of vasoactive intestinal peptide (VIP) using different oxidative electrophilic substitution agents

    International Nuclear Information System (INIS)

    Vasoactive Intestinal Peptide (VIP) is a linear 28 residue polypeptide with a wide range of biological activities. Various tumor cells express significant amounts of VIP receptors and this became the basis for use of radiolabelled VIP for the in vivo localization of adenocarcinomas. The VIP molecule contains two tyrosine residues, in positions 10 and 22, susceptible to iodination. This work describes the influence of the oxidation agent in the radiochemical purity and in the production of different labelled forms of VIP, analysed by high performance liquid chromatography (HPLC). Three labelling procedures using oxidant agent were employed. In the first one, Iodogen was prepared in the form of pre-coated reaction vial. In the second procedure, Iodogen was introduced as a suspension and the iodination were allowed to proceed for 30 minutes at room temperature with gentle stirring. The third labelling procedure used Chloramine T as oxidant agent after a few minutes of reaction (less than 3 minutes) at room temperature and with gentle stirring, the reaction was terminated by the addition of sodium metabisulfite solution. The radiochemical purity was determined by HPLC (R P C 18, 5 μm, 4.6 x 50 mm) eluted isocratically with 73:27 % TFA (trifluoroacetic acid 0.1% aqueous solution: acetonitrile) with a flow rate of 0.5 m L/minute. Free radioiodine was also determined by horizontal zone electrophoresis. Radioiodinated VIP was obtained with high labelling yield and radiochemical purity, in a short reaction time, when using Chloramine T as oxidant agent. The proposed isocratic HPLC system allows the separation of labelled VIP of high specific activity, necessary for receptor-mediated diagnostic procedures with radiopharmaceuticals. (author)

  17. Modification of low-density lipoprotein by different radioiodination methods

    International Nuclear Information System (INIS)

    Scintigraphic imaging of radiolabeled low-density lipoproteins (LDL) is an interesting tool for the understanding of its role in pathomechanism of atherosclerosis. Metabolism of native LDL shows quite different pattern and kinetics as compared to that of modified LDL which is not mediated by classical LDL-receptor and accumulates in atherosclerotic lesions to form lipid-laden foam cells. Therefore we were interested whether radiolabelling of LDL induces structural modifications. We performed the iodine labeling of LDL for scintigraphic imaging of atherosclerosis by three different methods: chloramine-T (A), iodine monochloride (B) and iodogen (C). The highest radiolabelling yield of 125I was obtained by the iodogen method (75.44±13.52%) and the lowest (49.01±12.74%) by iodine monochloride. Chloramine T showed a labeling yield of 62.82±6.17%. The stability of the tracer was very high with all the methods, persisting up to 6 h (98.83±1.2% - 91.38±4.7%, 15 min vs 6 h after labeling). For the first time we not only investigated the influence of radiolabelling on relative electrophoretic mobility (REM), but also various oxidation parameters such as baseline dienes (BD), thiobarbituric acid reactive substances (TBARS), endogenous peroxides (POX) and oxidation resistance in the copper-mediated oxidation system (expressed as lag-time) were measured. Furthermore, oxidation- derived fragmentation of the lipoproteins was examined with SDS-PAGE electrophoresis. Data are expressed as % change compared to native LDL before radiolabeling. BD were reduced by 32% using the method (A), but increased by 33% and 47% with the monochloride (B) and iodogen method (C), respectively. The effect on lag-time was comparable for all the three methods, ranging from 25 to 36% reduction in lag-time. TBARS were strongly increased 5-7 fold by all the methods. REM was changed by all three methods. While by methods A and C we have found a moderate increase in REM by 1.75 and 2.0 fold

  18. Modification of low-density lipoprotein by different radioiodination methods

    Energy Technology Data Exchange (ETDEWEB)

    Sobal, G. E-mail: grazyna.sobal@akh-wien.ac.at; Resch, U.; Sinzinger, H

    2004-04-01

    Scintigraphic imaging of radiolabeled low-density lipoproteins (LDL) is an interesting tool for the understanding of its role in pathomechanism of atherosclerosis. Metabolism of native LDL shows quite different pattern and kinetics as compared to that of modified LDL which is not mediated by classical LDL-receptor and accumulates in atherosclerotic lesions to form lipid-laden foam cells. Therefore we were interested whether radiolabelling of LDL induces structural modifications. We performed the iodine labeling of LDL for scintigraphic imaging of atherosclerosis by three different methods: chloramine-T (A), iodine monochloride (B) and iodogen (C). The highest radiolabelling yield of {sup 125}I was obtained by the iodogen method (75.44{+-}13.52%) and the lowest (49.01{+-}12.74%) by iodine monochloride. Chloramine T showed a labeling yield of 62.82{+-}6.17%. The stability of the tracer was very high with all the methods, persisting up to 6 h (98.83{+-}1.2% - 91.38{+-}4.7%, 15 min vs 6 h after labeling). For the first time we not only investigated the influence of radiolabelling on relative electrophoretic mobility (REM), but also various oxidation parameters such as baseline dienes (BD), thiobarbituric acid reactive substances (TBARS), endogenous peroxides (POX) and oxidation resistance in the copper-mediated oxidation system (expressed as lag-time) were measured. Furthermore, oxidation- derived fragmentation of the lipoproteins was examined with SDS-PAGE electrophoresis. Data are expressed as % change compared to native LDL before radiolabeling. BD were reduced by 32% using the method (A), but increased by 33% and 47% with the monochloride (B) and iodogen method (C), respectively. The effect on lag-time was comparable for all the three methods, ranging from 25 to 36% reduction in lag-time. TBARS were strongly increased 5-7 fold by all the methods. REM was changed by all three methods. While by methods A and C we have found a moderate increase in REM by 1.75 and 2

  19. Labeling Lanreotide with 125I and 188Re. China

    International Nuclear Information System (INIS)

    Lanreotide (D-β-Nal-Cys-Try-D-Trp-Lys-Val-Cys-Thr-NH2) is a new somatostatin analogue. It can bind to human somatostatin receptor (hSSTR) subtype 2 through 5 with high affinity and to hSSTR subtype 1 with low affinity. We investigate labeling condition, quality control and stability in vitro of 125I-Lanreotide and 188Re-lanreotide respectively. (A) Lanreotide is labeled with 125I using Chloramine T. The effect of reaction condition (such as reaction time, pH value, Lanreotide amount, quantity of Chloramine T and reaction volume) on labeling yield is investigated in detail. (B) The labeling yield and radiochemical purity (RP) is measured with paper chromatography (PC) and Sep-Pak C18 Cartridge. For PC method, 125I-Lanreotide is spotted on the Whatman No.1 paper and developed in the mixture of CH3CH2CH2CH2OH and CH3CH2OH and NH4OH (v/v/v=5:2:1), the Rf value of every component in the mobile phase is given in table 1. For Sep-Pak C18 Cartridge methods each cartridge is washed with 10 ml of ethanol followed by 10 ml of iso-CH3CH2CH2OH solution. Aliquots of 0.1 mI sample is loaded onto the cartridge, unbound peptide (sodium iodine-125) is eluted with 5 ml of 0.5mol/L sodium acetate solution, 125I-Lanreotide is eluted with 5 mI of 95% aqueous ethanol solution. (C) The stability of 125I-Lanreotide in vitro is investigated by labeling compound incubating for 48 hours at 37 deg. C in the 0.9% sodium chloride solution and RP is tested by PC at specific time intervals. (D) Lanreotide is labeled directly with 188Re via the mixture of citrate and tartate using stannous chloride as reduced agent. The influence of reaction conditions such as pH, temperature, amount of stannous chloride, amount of Lanreotide and reaction time on labeling yield is investigated in detail. At the time, the stability in vitro quality control and animal test are evaluated

  20. Selective mono-radioiodination and characterization of a cell-penetrating peptide. L-Tyr-maurocalcine

    International Nuclear Information System (INIS)

    Mono-and poly-iodinated peptides form frequently during radioiodination procedures. However, the formation of a single species in its mono-iodinated form is essential for quantitative studies such as determination of tissue concentration or image quantification. Therefore, the aim of the present study was to define the optimal experimental conditions in order to exclusively obtain the mono-iodinated form of L-maurocalcine (L-MCa). L-MCa is an animal venom toxin which was shown to act as a cell-penetrating peptide. In order to apply the current direct radioiodination technique using oxidative agents including chloramine T, Iodo-Gen registered or lactoperoxidase, an analogue of this peptide containing a tyrosine residue (Tyr-L-MCa) was synthesized and was shown to fold/oxidize properly. The enzymatic approach using lactoperoxidase/H2O2 was found to be the best method for radioiodination of Tyr-L-MCa. MALDI-TOF mass spectrometry analyses were then used for identification of the chromatographic eluting components of the reaction mixtures. We observed that the production of different radioiodinated species depended upon the reaction conditions. Our results successfully described the experimental conditions of peptide radioiodination allowing the exclusive production of the mono-iodinated form with high radiochemical purity and without the need for a purification step. Mono-radioiodination of L-Tyr-MCa will be crucial for future quantitative studies, investigating the mechanism of cell penetration and in vivo biodistribution.

  1. Preparation, purification and primary bioevaluation of radioiodinated ofloxacin. An imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Kandil, Shaban; Seddik, Usama; Hussien, Hiba; Shaltot, Mohamed [Atomic Energy Authority, Cairo (Egypt). Cyclotron Project; El-Tabl, Abdou [Monofia Univ. (Egypt). Faculty of Science

    2015-07-01

    The broad-spectrum antibiotic agents have been demonstrated as promising diagnostic tools for early detection of infectious lesions. We set out ofloxacin (Oflo), a second-generation fluoroquinolone, for the radioiodination process. In particular, this was carried out with {sup 125}I via an electrophilic substitution reaction. The radiochemical yield was influenced by different factors; drug concentration, different oxidizing agents, e.g. chloramine-T, iodogen and n-bromosuccinimide, pH of medium, reaction time, temperature and different organic media. These parameters were studied to optimize the best conditions for labeling with ofloxacin. We found that radiolabeling in ethanol medium showed a 70% radiochemical yield of {sup 125}I-ofloxacin. The radioiodination was determined by means of TLC and HPLC. The cold labeled Oflo ({sup 127}I-Oflo) was prepared and controlled by HPLC. The cold labeled Oflo was also confirmed by NMR and MS techniques. Furthermore, biodistribution studies for labeled {sup 125}I-Oflo were examined in two independent groups (3 mice in each one); control and E. Coli-injected (inflamed). The radiotracer showed a good localization in muscle of thigh for inflamed group as compared to control. In conclusion, ofloxacine might be a promising target as an anti-inflammatory imaging agent.

  2. {sup 99m}Tc-labeled chimeric anti-NCA 95 antigranulocyte monoclonal antibody for bone marrow imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sarwar, M.; Higuchi, Tetsuya; Tomiyoshi, Katsumi [Gunma Univ., Maebashi (Japan). School of Medicine] [and others

    1998-09-01

    Chimeric mouse-human antigranulocyte monoclonal antibody (ch MAb) against non-specific cross-reacting antigen (NCA-95) was labeled with {sup 99m}Tc (using a direct method) and {sup 125}I (using the chloramine T method), and its binding to human granulocytes and LS-180 colorectal carcinoma cells expressing carcinoembryonic antigen on their surfaces, cross-reactive with anti-NCA-95 chimeric monoclonal antibody, increased in proportion to the number of cells added and reached more than 80% and 90%, respectively. In biodistribution studies, {sup 99m}Tc and {sup 125}I-labeled ch anti-NCA-95 MAb revealed high tumor uptake, and the tumor-to-blood ratio was 2.9 after 24 hours. The tumor-to-normal-organ ratio was also more than 3.0 in all organs except for the tumor-to-kidney ratio. Scintigrams of athymic nude mice confirmed the results of biodistribution studies that showed higher radioactivity in tumor and kidney of the mice administered with {sup 99m}Tc-labeled ch MAb. A normal volunteer injected with {sup 99m}Tc-labeled ch anti-NCA-95 antigranulocyte MAb showed clear bone marrow images, and a patient with aplastic anemia revealed irregular uptake in his lumbar spine, suggesting its utility for bone marrow scintigraphy and for the detection of hematological disorders, infections, and bone metastasis. (author)

  3. Characterization of tumour virus proteins. I. radioimmunoassay of the P27 protein of avian viruses

    International Nuclear Information System (INIS)

    The major structural protein of avian oncornaviruses, a core component of about 27000 daltons, has been measured by radioimmunoassay. The purified protein was labelled with 125Iodine by chloramine-T method. The immune serum titer was defined as the highest serum dilution able to precipitate 50% of the labelled antigon present in the system. Standard competition curve was constructed in order to determine the equivalents of protein, in a system with limiting antibody concentration. In the experimental conditions used, 0.14 ng of AMV-P27 inhibited 50% of 125I-AMV-P27 (1.0 ng) precipitation. The 125I-AMV-P27 vs anti-AMV-P27 system was used to study the competition of normal cells, purified virus suspension, productive cells and supernatant fluids. Most of the chicken ombryo fibroblast showed expression of this viral component. The phenomena of cell transformation, the increase in total protein, and the expression of P27 were studied in rapid transformation of CEF by RSV-SR sub(A)

  4. Proteins labelling with 125I and experimental determination of their specific activity

    International Nuclear Information System (INIS)

    A standardization of the labelling technique of proteins with 125I and the control of the obtained products, principally their specific activities was performed, in order to utilize them correctly in radioimmunoassays. The quantities of chloramine-T and sodium metabisulphite were lowered, with regard to the original method, to 3.6 and 9.6 μg respectively. Under these conditions, optimal yields and radioiodinated proteins with good immunological activities were obtained. It was found that the specific activity calculated, as usual, from the yield obtained by electrophoresis, is higher than the real value. For these reasons the yields and the corresponding specific activities were determined from ascending chromatographies performed with 70 per cent methanol as solvent, during two hours in darkness. The radioimmunoassay displacement curves obtained with proteins labelled which the proposed method and the specific activities of which were calculated from their radiochromatographic patterns, were reproducible and gave a percentage of bound radioiodinated protein in the absence of cold protein of 50 +- 4. (author)

  5. Development of an 'In vitro' system for the caption essay of T3; Desarrollo de un sistema 'In vitro' para el ensayo de captacion de T3

    Energy Technology Data Exchange (ETDEWEB)

    Lavalley, C.; Ferro, G.; Zambrano, F.; Lezama, J

    1990-02-15

    Triiodothyronine uptake (T3U) is a qualitative technique for evaluation of the unsaturation capacity of thyroid binding globulin (TBG). This paper presents results related to a T3 standardized serum and the integration of T3-I-125, and adsorbent for labelled hormone. Labelled hormone were prepared by the chloramine T method and then purified by high performance liquid chromatography. The specific activity was 500 {mu} Ci/ {mu} g. Various adsorbents such as: Norit A Charcoal, calcium silicate, talc, bovine serum albumin macroaggregated (BSAM) were used in different buffers as: Tris-HCl, barbital and Michaelis. Standardized serum was prepared by mixing different euthyroid sera. Best conditions for T3U assays were achieved with 15 mg/ml. BSAM at pH 8.6 in presence of Tris-HCl buffer for hypothyroid and hyperthyroid sera, for which we obtained < 0.9 {+-} 0.04 and > 1.1 {+-} 0.05 respectively as a T3U index with a 3.0 % of coefficient variation. The reagents so prepared can be conveniently used for T3U assays. (Author)

  6. The characters of 125I-VIP binding to the receptors derived from human gastrointestinal adenocarcinoma and their adjacent tissues

    International Nuclear Information System (INIS)

    To investigate the characteristics of 125I-VIP binding to human gastrointestinal adenocarcinoma and their adjacent tissue. VIP was labelled with Na 125I using chloramine -T method, separated by Sephadex G-50 column chromatography and examined by silica 60F254 thin layer chromatography. The effects of time and temperature on the specific binding were examined, saturable binding and competitive binding between 125I-VIP and VIP receptors in membranes from gastrointestinal adenocarcinoma and their adjacent tissue were carried out. The results showed that labelling rate was 70%, the specific activity of 125I-VIP was 18TBq/mmol, the radiochemical purity was better than 98%. A single specific binding sites of high affinity were present in gastric adenocarcinoma and its adjacent tissue as well as in colon adenocarcinoma and its adjacent tissue. The Kd and Bmax values were 1.19 nmol/L and 339 fmol/mg protein, 1.26 nmol/L and 156 fmol/mg protein, 0.97 nmol/L and 304 fmol/mg protein, 1.53 nmol/L and 151 fmol/mg protein respectively. The present study demonstrated that the binding sites of VIP on human gastrointestinal adenocarcinoma were more abundant than their adjacent tissue membrane, which provide valuable experimental evidence for VIP receptor imaging

  7. Preparation of 125I-labeled human growth hormone of high quality binding properties endowed with long-term stability

    International Nuclear Information System (INIS)

    125I-labeled human growth hormone (125I-labeled.hGH) was prepared by using two variants of the chloramine T labelling procedure and purified by polyacrylamide gel electrophoresis (PAGE) of the reaction mixture. Variant A produced a tracer with high specific activity (100 +/- 10 microCi/microgram), high maximal binding capacity to antibodies (93%) and long-term stability (at least 150 days at -20/degree/C). No diiodinated tyrosil residues could be detected in this tracer. Variant B was devised to obtain higher yields of labeled hormone. The electrophoresis of the iodination mixture revealed two radioactive components with Rm values of 0.49 and 0.55 which result from the iodination of hGH variants preexisting in the starting material. Both tracers had similar specific activities (70 +/- 10 microCi/microgram), high maximal binding capacity to antibodies or receptors (80-100%, after 80 days of their obtention) and high stability (at least 100 days at -20/degree/C). It is concluded that the iododerivatives of hGH obtained by either method are adequate to perform radioimmunoassay and receptor studies and have long-term stability

  8. Iodine-125 Chitosan-Vitamin C complex. Preparation, characterization and application

    Energy Technology Data Exchange (ETDEWEB)

    Elbarbary, Ahmed M. [National Center for Radiation Research and Technology, Cairo (Egypt). Polymer Chemistry Dept.; Shafik, H.M.; Ebeid, N.H.; Ayoub, S.M. [Atomic Energy Authority, Cairo (Egypt). Hot Lab. Center; Othman, Sameh H. [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Center

    2015-07-01

    In heterogeneous conditions, water soluble Chitosan-Vitamin C Complex (CSVC) is successfully synthesized via the ionic interaction between γ-degraded CS and VC. Chitosan (CS) of low molecular weight (MW) is prepared using γ-irradiation method. The coupling of CS and vitamin C (VC) is carried out by the chemical treatment of VC with the γ-degraded CS. The formation of CSVC complex instead of physical mixture is confirmed by FT-IR and UV spectrometry. Characterization by transmission electron microscope (TEM) and dynamic light scattering (DLS) shows the formation of a nanostructure in 40 nm range. The preparation of labeled CSVC was performed using chloramines-T oxidation method. The labeling feasibility of CSVC nanostructure by Iodine-125 ({sup 125}I) is investigated. The optimized conditions of labeling are thought to be 50 μg of oxidizing agent, pH 3, and one minute reaction time. The Biodistribution activity of {sup 125}I radiolabeled CSVC nanostructure ({sup 125}I-CSVC) is examined on a group of different ascites tumor bearing mice. Calculation of the biodistribution percentages shows that the tumor, liver, and kidney are the targeting organs of {sup 125}I-CSVC nanostructure.

  9. Composition of cross-linked 125I-follitropin-receptor complexes

    International Nuclear Information System (INIS)

    Both of the alpha and beta subunits of intact human follitropin (FSH) were radioiodinated with 125I-sodium iodide and chloramine-T and could be resolved on sodium dodecyl sulfate-polyacrylamide gels. Radioiodinated FSH was affinity-cross-linked with a cleavable (nondisulfide) homobifunctional reagent to its membrane receptor on the porcine granulosa cell surface as well as to a Triton X-100-solubilized form of the receptor. Cross-linked samples revealed three additional bands of slower electrophoretic mobility, corresponding to 65, 83, and 117 kDa, in addition to the hormone bands. The hormone alpha beta dimer band corresponded to 43 kDa. Formation of the three bands requires the 125I-hormone to bind specifically to the receptor with subsequent cross-linking. Binding was prevented by an excess of the native hormone but not by other hormones. A monofunctional analog of the cross-linking reagent failed to produce the three bands. Reagent concentration-dependent cross-linking revealed that their formation was sequential; smaller complexes formed first and then larger ones. When gels of cross-linked complexes were treated to cleave covalent cross-links and then electrophoresed in a second dimension, 18-, 22-, and 34-kDa components were released, in addition to the alpha and beta subunits of the hormone

  10. Oxidative radioiodination damage to human lactoferrin

    International Nuclear Information System (INIS)

    Oxidative iodination of human lactoferrin (Lf) commonly performed by using the chloramine-T, the Iodogen or the lactoperoxidase method produces an unreliable tracer protein because of excessive and heterogeneous polymer formation. Before iodination a minor tetramer fraction may be demonstrable in iron-saturated Lf only. 125I-Lf polymers are mainly covalently linked, as suggested by the lack of substantial dissociation in SDS/polyacrylamide-gel electrophoresis. Damage to the 125I-Lf monomer may be another consequence of oxidative iodination. This is demonstrated in SDS/polyacrylamide-gel electrophoresis where 50% of the radioactivity of apparently normal monomer (Msub(r) 75000) is displaced to a lower-Msub(r) region (30000-67000) after reduction with dithiothreitol. Non-oxidative iodination by the Bolton-Hunter technique produces an antigenetically stable tracer that is not being subjected to polymerization and monomer degradation as judged by high performance gel chromatography and SDS/polyacrylamide-gel electrophoresis with and without dithiothreitol treatment. It is concluded that oxidation in itself leads to covalent non-disulphide cross-linking between human Lf molecules and, possibly, to intramolecular peptide-bond breaking becoming unmasked under reducing conditions. (author)

  11. Preparation of 5-Iodo-2'- deoxyuridine labelled with 125 I

    International Nuclear Information System (INIS)

    5-Iodo-2'-deoxyuridine (IUdR), an analogue of thymidine is taken up by the proliferating cells during DNA synthesis. When IUdR is labelled with 125 I, due to Auger electrons from 125 I, this analogue of thymidine is very effective in cell destruction when is internalized. Recently, radioiodinated (125 I and 123 I) IUdR is considered a potential therapeutic agent, for treatment of cancer.125 I-IUdR was prepared by direct radioiodination of 2'-deoxyuridine (UdR), using chloramine T method. The radioiodination reaction was studied by varying the reaction parameters such as temperature and reaction time. The yield was improved by heating the reaction mixture to 65 deg. C for 10 min. Purification of 125 I-IUdR was carried out by gel filtration over a Sephadex G 25 column using 0.05 M citrate buffer (pH = 6). The yield of the reaction as well as the radiochemical purity were determined by paper electrophoresis using Whatman chromatography paper No.1, 0.05 M phosphate buffer at 13 V/cm. The analyse time was 1 h. The yield of radioiodination reaction was ≅70% and the radiochemical purity of 125 I-IUdR prepared by this method was: 91-92%. (authors)

  12. An immunoradiometric assay (IRMA) using an iodinized monoclonal antibody in the determination of two glycoprotein hormones, thyrotropine (TSH) and human choriongonadotropine (HCG)

    International Nuclear Information System (INIS)

    An immunoradiometric assay was developed for the determination of thyrotropine that uses an iodinized monoclonal antibody and a double-antibody separation technique. A monoclonal antibody to TSH served for a tracer, which was labelled with iodine-125 using the chloramine-T method and found to be sufficiently stable. The 1st antibody was rabbit anti-TSH made into a 1:500 dilution. Anti-rabbit globulin was chosen as the 2nd antibody. The basic concept of combining a monoclonal antibody tracer and a double-antibody separation technique proved to be an unfortunate one, as far as the development of an IRMA for hCG was concerned. In the determination of TSH, the IRMA's lower limit of detection was found to be 0.3 μIU/ml. By contrast with a RIA used on a routine basis in the same laboratory, the IRMA under investigation appeared to more susceptible to fluctuations. Further tests will be needed to gain better insights into the causative factors. (orig./MG)

  13. Radioimmunoassay of Human Thyrotropin - Part 1. Plasma TSH levels in various thyroid functions

    International Nuclear Information System (INIS)

    The radioimmunoassay of human thyrotropin was performed in various thyroid states, utilizing the anti-h-T.S.H. antibody and purified human thyrotropin supplied from National Institute of Arthritis and Metabolic Diseases, Bethesda, Ma., U.S.A., and human thyrotropin standard-A obtained from National Institute for Biologic Standards, Mill Hill, London, England. 131I labelled h-TSH was prepared after the Chloramine-T method of Greenwood et al. This double antibody system had a assay sensitivity of about l. 0 μU/ml of plasma HTS-A and could detect the plasma h-TSH level in the euthyroid patients. Plasma h-TSH level of the normal 26 Korean was l.1±0. 83 μU/ml, and that of the 8 hypothyroidisms were 8.3 to 67.5 μU/ml. In hyperthyroidisms, no cases showed the plasma h-TSH levels over l. 0 μU/ ml. Between the hypothyroidism and euthyroidism, no overlap is noticed on plasma h-TSH levels. A case of transient hypothyroid state identified by determination of plasma h-TSH level is presented. These results revealed that the radioimmunoassay of h-TSH in plasma could be a sensitive method to diagnose the hypothyroidism, if not caused by a pituitary disease.

  14. Preparation of directly iodinated steroid hormones and related directly halogenated compounds

    International Nuclear Information System (INIS)

    The preparation of directly iodinated radioactive steroid hormones is described for use in radioimmunoassays or radiolocalization and treatment of human breast tumours. The radioactive iodinated steroid hormone is prepared by reacting a parent steroid hormone with an alkali metal iodide containing radioactive 123I, 125I, 130I or 131I in the presence of hydrogen peroxide or chloramine-T. The parent steroid hormones include the adrenal corticosteroids, the estrogens, the progestogens, the progestins and the diuretic and antidiuretic agents. The radioactive iodinated steroid hormone is prepared by iodinating the parent steroid hormone directly on the cyclopentanophenanthrene nucleus. The radioactive iodinated steroid hormones have the same antigenicity and receptor site specificity as the parent steroid hormone. The invention is illustrated by 1) the method of iodination of estradiol-17β, 2) results for the percentage labelling of several steroids and steroid hormones, 3) results for the radioimmunoassay of 125I-estradiol and 4) results for the binding of directly iodinated estradiol-17β in an estrogen receptor assay of human breast cancer. (U.K.)

  15. Synthesis of 125 I - Salicyl Hydroxamic Acid for Urinary Bladder Imaging

    International Nuclear Information System (INIS)

    Salicylhydroxamic acid is a salicylate derivative. Radiolabeling of Salicyl hydroxamic acid ( SHA ) with iodine-125 may have considerable interest for imaging of urinary bladder. This study is aimed to optimize the radiolabeling yield of Salicyl hydroxamic with radio iodine (125-123) using chloramine - T (CAT) as an oxidizing agent with respect to factors that affect the reaction conditions such as SHA amount, CAT amount, reaction time and ph of the reaction mixture. In - vitro stability of the radiolabeled complex was checked and it was found to be stable for up to 24 h. 125 I-SHA was injected via intravenous administration routes into normal male Sprague – Dawley rats. Bio - distribution studies have revealed that 125I-SHA was excreted in urine with extent that it could give a clear image for urinary bladder especially if the bladder it tightly closed. The amount of 125 I - Salicyl hydroxamic excreted was increased in case of giving potassium bicarbonate to rat before injection of 125 I-SHA. The result of biodistribution study of 125 I - SHA in experimental animal suggest ed the possibility of using 123 I-SHA to image the urinary bladder

  16. Spectrophotometric Determination of Trace Cyanide in Fruit Wines by the Catalytic Reaction of Ninhydrin Following Micro-Distillation

    Directory of Open Access Journals (Sweden)

    Saksit Chanthai

    2014-03-01

    Full Text Available Trace analysis of cyanide (CN based on the absorbance of the catalytic reaction of ninhydrin (NH in the presence of CN- was developed. This reaction was investigated consisting of 0.08 M NH, 0.4 M Na2CO3, 1% (v/v Tween 20 and 2.5 M NaOH in 5-mL final volume. The absorbance of the CN-NH complex was measured against the reagent blank at 598 nm. The calibration curve was widely linear over the range of 40-160 µg/L with r2 >0.99. The method recoveries of free cyanide, bound cyanide and total cyanide for wine samples were found in the range of 76.2-89.2%, 73.2-91.2% and 76.8-94.8%, respectively, at 250 µg/L CN- spiked level. Limit of detection was 6 µg/L. The reproducibility of the proposed method was less than 4.44%. This method was then applied for local Thai fruit wines. No trace amount of cyanide was detected, as if high recovery (88.4% of the micro-distillation was guaranteed. The obtained results were in agreement with those of the chloramine-T/barbituric acid-pyridine method with no statistically significant difference at 95% confidence level.

  17. Biodistribution and radioimmunoimage of iodine-125 labeled anti-human ADAM15 polyclonal antibody in nude mice bearing human gastric carcinoma xenografts

    International Nuclear Information System (INIS)

    Objective: To investigate the biodistribution of Iodine-125 labeled anti-human ADAM15 polyclonal antibody in nude mice bearing human gastric carcinoma xenografts. Methods: The anti-human ADAM15 polyclonal antibody was labeled with I-125 using Chloramine-T method. The labeling efficiency and radiochemical purity of 125I-anti-ADAM15 antibody were measured. The SPECT planar imaging of nude mice bearing gastric carcinoma xenografts were performed at 1, 4, 8, 24, and 48 h post-injection and the biodistribution of 125I-anti-ADAM15 antibody was measured at 48 h after injection. Results: The labeling efficiency of 125I-anti-ADAM15 antibody was (75.16±9.43)% and its radiochemical purity was (99.44±0.21)% . Tumors could be cleanly visualized in SPECT planar images, and the radioactivity ratio of tumor to non-tumor tissue was 3.84±0.43 at 48 h post-injection. Conclusion: 125I-anti-ADAM15 antibody can target the gastric carcinoma in vivo, and provide good radioimmunoimages. (authors)

  18. Pilot plant studies on the treatment of El Atshan Uranium Ores, Eastern Desert, Egypt

    International Nuclear Information System (INIS)

    The present work deals with studying the different processes leading to the preparation of commercial uranium concentrate (yellow cake) from El Atshan granitic ore material (0.077%U) after acid leading of the latter, the two common extraction techniques of uranium from the obtained sulphate leach liquor; namely, anion exchange rein and solvent extraction have been studied. The studied leaching and extraction conditions-realized on the lab scale-were applied to inches pilot plant unit (capacity 150 kg ore). An average leaching leaching efficiency exceeding 88% has been achieved. Using anion exchange resin, it has been possible to prepare a uranium peroxide concentrate assaying a uranium content of about 67% U3 O8. Only trace amount of Ca, Fe, Po4, Cr and Pb have been detected. On the other hand, sodium uranate, as a uranium precipitate was prepared from the strip solution of the loaded solvent (di-2-ethyl phosphoric acid concerned with the evaluation of a new optimized technique for the principle of chloramine-T method used for insulin iodination for the modified procedure can be carried out under normal condition of room temperature, employed longer reaction times and omitted the addition of inorganic reducing salts maintaining efficient iodination and avoiding denaturation to obtain labels of exceedingly high specific activity and small quantities of insulin for in vitro usage in the investigation of human erythrocytes 125 I-inulin binding capacity in normal and in some disease status. 9 figs., 2 tabs

  19. Radioimmunoassay of chicken growth hormone using growth hormone produced by recombinant DNA technology: validation and observations of plasma hormone variations in genetically fat and lean chickens

    Energy Technology Data Exchange (ETDEWEB)

    Picaper, G.; Leclercq, B.; Saadoun, A.; Mongin, P.

    1986-01-01

    A radioimmunoassay (RIA) of chicken growth hormone (c-GH) has been developed using growth hormone produced by recombinant DNA technology. The best rabbit antiserum was used at 1/300,000 final dilution. Hormone labelling by iodine-125, achieved by chloramine T, allowed a specific activity of 3.7 MBq/..mu..g. The equilibrium curves show that optimal conditions of incubation were reached at room temperature for 24h. This RIA used a second sheep antibody which precipitated the whole c-GH bound to the first antibody in the presence of polyethylene glycol solution (6%) at room temperature for 30 min. In our conditions, sensitivity was about 30 pg of c-GH per tube. Coefficient of variation was around 10%. No cross reaction was found with avian LH and prolactin. Thyrotrophin-releasing hormone (TRH) injection to young chickens induced 20-fold higher plasma c-GH concentrations. Simultaneous injection of somatostatin and TRH slightly reduced these concentrations. Hypoglycemia induced by insulin led to a drop of the plasma c-GH concentration. Conversely, refeeding or glucose load induced slight increases of the c-GH level. Genetically fat chickens tended to exhibit higher plasma c-GH concentrations than lean chickens.

  20. Biochemical assays with radio-iodinated substrates

    International Nuclear Information System (INIS)

    A sensitive radiochemical method for the measurement of nanogram amounts of ammonia applicable to studies of enzymatic or other processes releasing or utilizing ammonia was developed. The method is based on a modified Berthelot reaction between ammonia and an aqueous alkaline solution of phenol and sodium hypochloride to yield indophenol. The radioactive tracer used is 125I-o-iodophenol, prepared by iodination of phenol with 125I by the chloramine-T method. A chloroform/carbon tetrachloride mixture is used to extract unreacted 125I-o-iodophenol from the reaction mixture; the 125I-labelled product remains in the aqueous phase and is measured by scintillation counting. Non-protein nitrogenous substances and certain other compounds interfere with the reaction, which cannot thus be used to measure ammonia directly in biological fluids. The glass Conway microdiffusion cell may, however, be utilized to isolate small amounts of ammonia from such fluids for measurement. The fluid is placed in the centre well of the cell and cold water in the outer well. Warm saturated potassium carbonate solution is then added to the centre well to expel the ammonia gas which is absorbed by the water. Technical details of the method are given

  1. Preparation of a 125I-labelled conjugate of pteroylglutamic acid and its use in a radio ligand assay of folate in blood

    International Nuclear Information System (INIS)

    The synthesis of a 125I-labelled folate derivative is described for use in the radioassay of folate in serum and whole blood haemolysate. Pteroylglutamic acid (PGA) was conjugated with tyramine in dimethylformamide solution using a mixed anhydride procedure. The product was characterised by its ultra-violet absorption spectrum and its electrophoretic mobility. Iodination of this conjugate with 125I, using Chloramine-T as oxidant, was carried out and gave high incorporation of label. The iodinated product, which was separated from other reactants by a simple and rapid Amberlite-IRA-400 resin separation technique, bound avidly to the folate-binding protein of cow's milk, enabling dose response curves to be constructed which provided a sensitive and precise assay for folate in serum and whole blood haemolysates. Comparison of the results obtained on serum and whole blood haemolysates with an established microbiological procedure gave good agreement. The radioassay described had improved precision at low folate levels where the discriminating need of the assay is greatest. (author)

  2. Preparation of ( sup 123 I)- and ( sup 125 I)epidepride: a dopamine D-2 receptor antagonist radioligand

    Energy Technology Data Exchange (ETDEWEB)

    Clanton, J.A.; Schmidt, D.E.; Ansari, M.S.; Manning, R.G.; Kessler, R.M. (Vanderbilt Univ., Nashville, TN (United States). School of Medicine); Paulis, T. de (Vanderbilt Univ., Nashville, TN (United States). School of Medicine Vanderbilt Univ., Nashville, TN (United States). Dept. of Chemistry); Baldwin, R.M. (Yale Univ., West Haven, CT (United States). Veterans Administration Medical Center Research)

    1991-07-01

    (S)-(-)-N-((1-ethyl-2-pyrrolidinyl)methyl)-5-({sup 123}I) iodo-2,3-dimethoxybenzamide (TDP 517) (proposed generic name, ({sup 123}I)epidepride) is the iodine-123 substituted analogue of isoremoxipride (FLB 457), both of which are very potent dopamine D-2 antagonists (epidepride K{sub D} 0.024 nM). ({sup 123}I) Epidepride was radioiodinated in 60-70% radiochemical yields in 35 min from the corresponding 5-(tributyltin) derivative using Na{sup 123}I with a specific radioactivity of 3000 Ci/mmol, and oxidized in situ with chloramine-T. The aryltin precursor was prepared from non-labelled epidepride by palladium-catalyzed stannylation using bis(tri-n-butyltin) in triethylamine. Alternatively, using no carrier-added Na{sup 125}I as the radioisotope, ({sup 125}I) epidepride at 2000 Ci/mmol specific radioactivity was prepared in 86% radiochemical yield and 99% radiochemical purity after purification by reverse phase HPLC in ethanolic phosphate buffer. (author).

  3. The transport of humic and fulvic acids through sand

    International Nuclear Information System (INIS)

    The objective of this work was to produce stable iodine-125 labelled humic and fulvic acids for use in field tests at the BGS borehole array at Drigg in Cumbria. The first part of the report describes iodine-125 labelling of humic and fulvic acids by oxidation of iodide-125 by chloramine-T. Although the apparent efficiency of labelling was high, some of the iodinated humic dissociated on standing and during passage through sand columns. The second part of the report describes the production of a more stable iodinated humic and fulvic acid. This was achieved by adding reducing agent to the reaction mixture after iodination of the humic material. The addition of reducing agent decreased the apparent labelling efficiency of the humic materials but increased the stability. The third part of the report describes the preparation of iodinated-fulvic acid for use in a field test. Gel column separation showed that 95% of the activity was bound to fulvic acid on the day of the field experiment. Samples of this material were passed through 55 cm long sand columns. I-125 breakthrough occurred simultaneously with tritium but a proportion remained on the column. This sorbed, or deposited, material then eluted very slowly from the column. (author)

  4. A radioimmunoassay of chicken growth hormone using growth hormone produced by recombinant DNA technology: validation and observations of plasma hormone variations in genetically fat and lean chickens

    International Nuclear Information System (INIS)

    A radioimmunoassay (RIA) of chicken growth hormone (c-GH) has been developed using growth hormone produced by recombinant DNA technology. The best rabbit antiserum was used at 1/300,000 final dilution. Hormone labelling by iodine-125, achieved by chloramine T, allowed a specific activity of 3.7 MBq/μg. The equilibrium curves show that optimal conditions of incubation were reached at room temperature for 24h. This RIA used a second sheep antibody which precipitated the whole c-GH bound to the first antibody in the presence of polyethylene glycol solution (6%) at room temperature for 30 min. In our conditions, sensitivity was about 30 pg of c-GH per tube. Coefficient of variation was around 10%. No cross reaction was found with avian LH and prolactin. Thyrotrophin-releasing hormone (TRH) injection to young chickens induced 20-fold higher plasma c-GH concentrations. Simultaneous injection of somatostatin and TRH slightly reduced these concentrations. Hypoglycemia induced by insulin led to a drop of the plasma c-GH concentration. Conversely, refeeding or glucose load induced slight increases of the c-GH level. Genetically fat chickens tended to exhibit higher plasma c-GH concentrations than lean chickens

  5. iodine 125 -tamoxifen (125ITX); radioligand for visualization of estrogen receptors: preparation and tissue distribution

    International Nuclear Information System (INIS)

    Tamoxifen,(Z) 2-[4-(1,2-diphenyl-1-butenyl) phenoxy] -N,N-dimethylethethanamine 2-hydroxy-1,2,3-propane tricarboxylate (TX) is a selective estrogen receptor antagonist for use in the treatment of breast cancer and other non-malignant estrogen dependant conditions. direct radioiodination of tamoxifen was done using chloramine-t as oxidizing agent and yielded 97% of 125ITX. the reaction mixture was heated at 50 c for 10 minutes . the ph of the reaction mixture was the most critical factor during this labeling reaction . iodine -125-tamoxifen was localized in the organs of interest with a percentage sufficient to produce a good image whereas their ratios to backgrounds were high (9.1 for breast/blood,6.4 for ovaries an uterus/blood at 8 h post injection). 125ITX was cleared by both the kidneys and the liver. at 8 post injection the excretion in urine was 28.5% and that in faeces was 22% . the thyroid uptake was very low (0.1%) indicating the in - vivo stability of 125ITX tracer. a specificity of the tracer to the breast and ovaries/uterus was established via prior administration of cold tamoxifen and estradiol that significantly reduced the localizing activity of the tracer

  6. Iodine-125 Nilutamide as Novel Radio-therapeutic Ligand for Androgen Receptor in Prostate Cancer

    International Nuclear Information System (INIS)

    Nilutamide is potent anti-androgen that is used in patients with metastatic prostate carcinoma. The labeling of nilutamide with iodine radioisotopes give an advantage to localize these radionuclides in prostate for imaging and/or therapy depending on the radionuclide used. During this study, nilutamide was labeled successfully with iodine-125 in a neutral ph medium using chloramine-T as oxidizing agent and the radiochemical yield obtained was greater than 96%. The biodistribution of the iodine-125-nilutamide in normal mice indicated the ability of the tracer to bind with specific receptors in prostate and other male organs with 3.5 % at 4 hours post injection. The clearance of the tracer from the blood pool was slow and equal to 40% of the initial blood uptake at 4 hours post injection. The in vivo stability of the tracer was established by the absence of the thyroid uptake. The competition binding was achieved via 1M injection of testosterone and IV injection of non-labeled nilutamide 2 hours before the administration of the tracer. The results referred to a significant reduction in the uptake of the tracer by the prior administration of testosterone and non-labeled nilutamide by 60% and 30%, respectively at 4 hours post injection

  7. Immunoradiometric assay of subunit H of human acidic isoferritin

    International Nuclear Information System (INIS)

    Acidic isoferritin (AIF) was isolated and purified from human heart muscle. Antisera against AIF were generated by immunizing rabbits and purified in affinity chromatography column which was conjugated with AIF. The immunoglobulins against AIF were made in solid-phase. 125I-monoclonal antibodies against H subunit of AIF(AIF-H) was prepared by the chloramine-T method. The AIF-H solid-phase IRMA was established and the data were processed by the automatic Spline function. The intra- and interbatch coefficients of variation were 2.443% and 10.160% respectively. The sensitivity was 0.736 μg/L and the recovery was 92.293%. The measuring range was 1.472-320 μg/L and ED50 was 23.05 μg/L. No cross-reaction was observed with AFP, CEA and LF, but there was 3.125% with ferritin. A parallel experiment demonstrated that serum matrix had no interference with this method. The level of serum AIF-H in 40 healthy men and women was 3.75 +- 1.85 μg/L and 2.92 +- 0.96 μg/L respectively while it was 8.39 +-3.87 μg/L in 10 patients with hepatoma. This method may therefore provide a valuable tool for diagnosis of tumor, especially for basic and clinical study of hepatoma

  8. Establishment of RIA for human obestatin and its primary application

    International Nuclear Information System (INIS)

    To establish a RIA method for human Obestatin and find out the expression changes and meaning of Obestatin during metabolic disorder diseases, synthetic human Obestatin was immunized and obtained anti-serum and chloramines-T method was used to radiolabel Obestatin with 125I, thus a RIA for Obestatin was established. The serum Obestatin levels of 50 patients with coronary heart disease, 50 patients with diabetes and in 50 healthy controls were determined by using self-established RIA. The results showed that both the shape of standard curve and metrical results of the Obestatin RIA established in this study were well. The serum Obestatin levels in patients with diabetes and coronary heart disease were significantly higher than that of healthy controls (P<0.001), while the serum Obestatin levels in patients with coronary heart disease were significantly higher than that of patients with diabetes (P<0.001). The results suggested that the established human Obestatin RIA was highly sensitive, concise and reliable. It can be used to detect human serum samples. The Obestatin may be a stress factor participating in the modulation of metabolic disorder diseases. (authors)

  9. Solid Phase Radioimmunoassay for Measuring Serum Triiodothyronine and Thyroxine using Different Preparations of Their Labeled Hormones

    International Nuclear Information System (INIS)

    The goal of the present work was oriented to prepare stable polystyrene coated tubes for direct radioimmunoassay (RIA) of triiodothyronine (T3) and thyroxine (T4) in human serum or plasma. Coating process was performed using sheep polyclonal antisera specific for each of T3 and T4. The stability study showed that these tubes could be stored for up to one year at 4 degree without any appreciable reduction in their binding. The preparations of 25I-T3 and 125I-T4 were carried out by two different methods [chloramine-T(Ch-T) and iodogen] . It was found that Ch-T method gave approximately the same results as iodogen method. Twenty five samples of different thyroid status were assayed for T3 and T4 using the present systems and with commerically available kits (coated tubes, DPC). The statistical analysis revealed good correlations between the results from the present systems using T3 and T4 tracers prepared by Ch-T and iodogen methods and The DPC kits. This may be extremely helpful in diagnosis and proper management of thyroid dysfunctions

  10. Iodine-123 labeled derivatives of methylphenidate: potential SPECT radiopharmaceuticals for brain dopamine transporters

    International Nuclear Information System (INIS)

    Since dl-threo-[11C]methylphenidate (Ritalin) and especially the more active enantiomer, d-threo-[11C]methylphenidate, have favorable properties for PET studies, we prepared two radioiodinated analogs of methylphenidate, p-[123I]iodomethylphenidate and m-[123I]iodo-p-hydroxymethylphenidate with a view to evaluating them as potential SPECT tracers. To prepare p-[123I]iodomethylphenidate, the p-tributyltin derivative was prepared from the previously reported p-bromomethylphenidate and reacted under acidic conditions with I-123 iodide plus chloramine-T at room temperature for 90 seconds. The predomimant radioactive product was obtained in 85% radiochemical yield and > 10 Ci/μmol specific radioactivity after HPLC purification. It had the same HPLC retention time as a spectroscopically characterized non-radioactive p-iodomethylphenidate standard prepared via nitration of methylphenidate and diazotization, after protection of the secondary amino group by benzoylation. A second radioiodinated methylphenidate derivative, m-[123)I]iodop-hydroxymethylphenidate was prepared in 80% radiochemical yield by direct iodination of the known p-hydroxymethylphenidate. In this case the non-radioactive standard was prepared by iodination of p-hydroxyritalinic acid using I2 and iodic acid, followed by esterification. (author)

  11. Human C-peptide. Pt. 1

    International Nuclear Information System (INIS)

    Synthetic human C-peptide bearing a tyrosine group at its amino end is labelled with 125iodine using chloramin T or hydrogen peroxide and lactoperoxidase. The results of the two methods are compared. Antiserum to synthetic human C-peptide (without tyrosine), which was partially coupled to rabbit albumin, is raised in guinea pigs and goats. Goats show to be superior to guinea pips concerning antibody production. The so-called 'hook effect' phenomenon is observed when setting up the standard curves for the radioimmunoassay. Monotonically decreasing standard curves are obtained on dilution of antiserum with a high antibody titer which was produced by repeated immunization in goats. Free C-peptide and C-peptide bound to antiserum are separated using the anion exchange resin amberlite. Using this separation technique we excluded unspecific binding of labelled C-peptide to protein fractions in serum of diabetics. The sensitivity of our radioimmunoassay is approx. 0.3 ng C-peptide/ml serum. Intra- and interassay variability are below 10%. Human proinsulin is the only substance found to crossreact with the antiserum. (orig.)

  12. Measurement of insulin in human sera using a new RIA kit. 1

    International Nuclear Information System (INIS)

    A sensitive and versatile radioimmunoassay (RIA) for insulin was established using human insulin standard, a specific guinea pig anti-insulin antiserum and rabbit anti-guinea pig serum. Radioiodination was performed according to a modified chloramine T method. Tracer preparations were used for as long as 6 weeks after iodination. The standard curve ranges from 0.044 to 1.2 nmol/l. The intra-assay coefficient of variation (CV) was 3-5% and the inter-assay CV was 6-9% in the optimal range between 0.4 and 0.9 nmol/l. The average recovery of human insulin added to plasma or serum samples was 100.2 ± 2.0% (n = 38) and 100.1 ± 1.9% (n = 42), respectively. In addition to human insulin, procine, canine, rabbit and bovine insulin can also be determined but not rat or mouse insulin. The cross-reactivity of the antiserum with porcine proinsulin was found to be 40 % on the molar basis. The range of mean fasting plasma insulin concentrations in healthy subjects and under various pathological conditions were estimated. (author)

  13. Clinical scale preparation and evaluation of {sup 131}I-Rituximab for Non-Hodgkin's lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Kameswaran, Mythili; Vimalnath, K. Viswanathan; Rajeswari, Ardhi; Joshi, Prahlad Vasudeo; Samuel, Grace [Bhabha Atomic Research Centre, Mumbai (India). Radiopharmaceuticals Div.; Sarma, H.D. [Bhabha Atomic Research Centre, Mumbai (India). Radiation Biology and Health Sciences Div.

    2014-09-01

    Radioimmunotherapy (RIT) with anti CD20 MoAb conjugated to a β{sup -} emitting radioisotope like {sup 131}I or {sup 90}Y has the added advantage of delivering radiation not only to tumor cells that bind the antibody but also due to a crossfire effect, to neighboring tumor cells inaccessible to the antibody. In order to make available an indigenous radioimmunotherapeutic agent for Non Hodgkin's Lymphoma (NHL), radioiodinated Rituximab has been prepared and evaluated at a clinical scale. Radioiodination of Rituximab was performed by the conventional Chloramine T method using 7.4 GBq Na{sup 131}I in a lead shielded plant. Six batches of radioiodination were prepared and characterized by electrophoresis and HPLC to evaluate the reproducibility of the product. The product remained stable retaining the radiochemical purity > 95% upto 5 days after radioiodination. In vitro cell binding studies and biodistribution studies in normal Swiss mice have indicated the potential of this molecule as a radioimmunotherapeutic agent for NHL. (orig.)

  14. Treatment of ichthyophthiriasis after malachite green. I. Concrete tanks at salmonid farms.

    Science.gov (United States)

    Rintamäki-Kinnunen, Päivi; Rahkonen, Mika; Mannermaa-Keränen, Anna-Liisa; Suomalainen, Lotta-Riina; Mykrä, Heikki; Valtonen, E Tellervo

    2005-04-01

    Since the use of malachite green was banned in many European countries, new alternative treatments have been tested to prevent white spot disease caused by Ichthyophthirius multifiliis. We tested formalin, potassium permanganate (KMnO4), chloramine-T, hydrogen peroxide (H2O2) and Per Aqua or Desirox alone or in combinations of 2 chemicals, one of which was always formalin, in 50 m2 concrete tanks at 2 farms producing salmon Salmo salar smolt in 2001 and 2002. Both Per Aqua and Desirox are combinations of peracetic acid, acetic acid and hydrogen peroxide. The alternative chemicals or their combinations can be used successfully to lower the parasite burden to such a level that no high mortality occurs during the first 4 wk after the start of an infection. This period of time allows the fish to develop immunity against these ciliates, and treatments can be reduced and stopped in due course. I. multifiliis decreased in number 3 to 4 wk after the beginning of the infection in all the treatments. Large differences in parasite burden and mortality occurred among the replicates in all except the Desirox-formalin tanks, which means that they are not as reliable as the malachite green-formalin used previously. It was also evident that the chemicals and their concentrations must be planned carefully to suit the conditions on each farm. PMID:15900690

  15. Iodine-125 Chitosan-Vitamin C complex. Preparation, characterization and application

    International Nuclear Information System (INIS)

    In heterogeneous conditions, water soluble Chitosan-Vitamin C Complex (CSVC) is successfully synthesized via the ionic interaction between γ-degraded CS and VC. Chitosan (CS) of low molecular weight (MW) is prepared using γ-irradiation method. The coupling of CS and vitamin C (VC) is carried out by the chemical treatment of VC with the γ-degraded CS. The formation of CSVC complex instead of physical mixture is confirmed by FT-IR and UV spectrometry. Characterization by transmission electron microscope (TEM) and dynamic light scattering (DLS) shows the formation of a nanostructure in 40 nm range. The preparation of labeled CSVC was performed using chloramines-T oxidation method. The labeling feasibility of CSVC nanostructure by Iodine-125 (125I) is investigated. The optimized conditions of labeling are thought to be 50 μg of oxidizing agent, pH 3, and one minute reaction time. The Biodistribution activity of 125I radiolabeled CSVC nanostructure (125I-CSVC) is examined on a group of different ascites tumor bearing mice. Calculation of the biodistribution percentages shows that the tumor, liver, and kidney are the targeting organs of 125I-CSVC nanostructure.

  16. Radioimmunoassay of TSH subunits in thyroid diseases and endocrine opthalmopahty

    International Nuclear Information System (INIS)

    Highly sensitive radioimmunoassays of hTSH sub-units were developed. The hormone preparations were labelled with 125-iodine according to a modified chloramine -T method, and purified by chromatography using biogel P6 and P60. Rabbit antisera were used as antibodies. Separation of the antibody-bound and of the free antigens was carried out via the double antibody method. The antiserum required for this purpose was obtained from a goat. The sensitivity of the assay was influenced by changing the protein content of the buffer, the incubation volume, the tracer amounts, the incubation time and the incubation temperature. For hTSH-α, the lowest detectable limit was found to be 50 pg/ml, for hTSH-#betta# 20 pg/ml. Thus, the sub-units could be determined for 98% of the patients under review. The #betta#-TSH radioimmunoassay is largely specific, TSH cross-reacts to a degree of 5%. The computerized evoluation was carried out by means of Spline approximation using the Siemens 4004 computer. Precision and accurateness are in compliance with generally accpted criteria. The serum levels of α and #betta# sub-units showed no discordancy with regard to TSH. In all groups of patients examined, the levels of the hormone-specific #betta#-chain were found to be exclusively dependent upon the actual thyroid activity. (orig.)

  17. Relationship between PLAP and high-risk pregnancy

    International Nuclear Information System (INIS)

    PLAP was isolated and purified from human placenta and the antiserum was obtained by immunizing the rabbits. A radioimmunoassay of PLAP (PLAP RIA) was established by labelling the antigen using the chloramine-T method. Its sensitivity was 1.54 μg/L, the recovery rate was between 96.7% and 105.2%, the intra- and inter-assay CV were 8.94% and 9.43%, respectively, the antiserum provided a linear response from 2 to 1000 μg/L. The assay has no cross-reactivity with liver AP. Serum level of PLAP were measured by PLAP RIA in 649 cases of normal pregnancy and 164 cases of high-risk pregnancy. The results indicated that the PLAP level increased proportionally with the advance of gestational age (r = 0.9843). In 33 cases of pregnancy induced hypertension and 21 cases of intrauterine fetal growth retardation, the PLAP were at significantly low level. In 7 cases of neonatal asphyxia and 26 cases of fetal distress, the PLAP level in the mother's serum were also low. In 53 cases of intrahepatic cholestasis of pregnancy, the PLAP level were similar to those of normal pregnancy. This study illustrated that PLAP RIA can play an important role in evaluation of placental function and fetal prognosis for cases of high-risk pregnancy

  18. Development of an 'In vitro' system for the caption essay of T3

    International Nuclear Information System (INIS)

    Triiodothyronine uptake (T3U) is a qualitative technique for evaluation of the unsaturation capacity of thyroid binding globulin (TBG). This paper presents results related to a T3 standardized serum and the integration of T3-I-125, and adsorbent for labelled hormone. Labelled hormone were prepared by the chloramine T method and then purified by high performance liquid chromatography. The specific activity was 500 μ Ci/ μ g. Various adsorbents such as: Norit A Charcoal, calcium silicate, talc, bovine serum albumin macroaggregated (BSAM) were used in different buffers as: Tris-HCl, barbital and Michaelis. Standardized serum was prepared by mixing different euthyroid sera. Best conditions for T3U assays were achieved with 15 mg/ml. BSAM at pH 8.6 in presence of Tris-HCl buffer for hypothyroid and hyperthyroid sera, for which we obtained 1.1 ± 0.05 respectively as a T3U index with a 3.0 % of coefficient variation. The reagents so prepared can be conveniently used for T3U assays. (Author)

  19. Evaluation of 3-[123I]iodo- and 3-[76Br]bromo-methylphenidate as potential tracers for the study of the dopamine transporter using SPECT and PET

    International Nuclear Information System (INIS)

    Full text: The psychomotor stimulant methylphenidate (MP) and several derivatives have demonstrated high affinity binding to a site on the dopamine transporter (DAT). Here we report the pharmacological evaluation of 3-[123I]iodomethylphenidate (l23MP) and 3-[76Br]bromomethyl phenidate (76BrMP) as potential SPET and PET tracers for the study of the DAT. Racemic 123IIMP and 76BrMP were synthesized from the corresponding 3-tributylstannyl methylphenidate using Na123I or NH476Br in the presence of chloramine-T. In vivo biodistribution of the active enantiomers of 123IMP in rats indicated a striatum (STR) to cerebellum (CB) ratio of 2.4 at 30 min p.i. Pretreatment of the rats with MP, WIN 35,428 and GBR 12909 reduced the STR/CB ratio to unity. Similarly, in vivo biodistribution of 76BrMP in rats also indicated high uptake in the striatum with a STR/CB ratio of 5.5 at 120 min p.i. Administration of 123IMP and 76BrMP in primates and examination by SPET and PET indicated a high accumulation of radioactivity in the striatum with rapid washout in other non-dopaminergic tissue. These results indicate that the active enantiomers of 123IMP and of 76BrMP have the potential for further development as SPET and PET tracers for the study of neurodegenerative diseases such as Parkinson's disease

  20. Establishment of 131I, 99mTc Labeling Methods to In-house Anti-CEA Antibodies and Evaluation of the Immunological Characteristics

    International Nuclear Information System (INIS)

    Cancer cells have several tumor-associated antigens on the cell surfaces, and antibodies against these antigens have been developed by many investigators. Radiolabeled antibodies have been used as new methods to diagnose and treat malignant tumors. Especially anti-carcinoembryonic antigen (CEA) is the most popular antibody for these purposes. In this investigation, we tried to label 131I and 99mTc to anti-CEA monoclonal antibodies which were developed in the Seoul National University College of Medicine. We found CEA-79 and CEA-92 antibodies had the better immunological characteristics among 8 anti-CEA monoclonal antibodies. And radioiodination of CEA-79 could be performed by chloramine-T method, while radioiodination of CEA-92 by iodogen method. To label these antibodies with 99mTc, we used pretargeting transchelation as direct labeling method. At first, 99mTc was bound to glucaric acid, and monoclonal antibody was reduced by β-mercaptoethanol. When these were incubated together, 99mTc bound to glucarate was switched to monoclonal antibody because of higher affinity. We established conditions of several steps in this method. Anti-CEA monoclonal antibodies labeled with 131I and 99mTc are expected to be used valuably in the detection and treatment of malignant tumors.

  1. Potential cerebral perfusion agents: synthesis and evaluation of a radioiodinated vinylalkylbarbituric acid analogue

    International Nuclear Information System (INIS)

    A new iodinated barbiturate has been prepared. Treatment of 5-chloropentyne and propargyl bromide with diethyl 2-ethyl-2-sodiomalonate (DESM) provided diethyl 2-ethyl-2-(1-pentyn-5-yl)malonate (3) and diethyl 2-ethyl-2-propargylmalonate (4), respectively. Similar condensation of DESM with (E)-(5-iodo-1-penten-1-yl)boronic acid (9) or the reaction of catecholborane with 3 provided diethyl (E)-2-ethyl-2-(1-borono-1-penten-5-yl)malonate (8). The direct sodium iodide-chloramine-T iodination of 8 or the treatment of (E)-1,5-diiodo-1-pentene (10) with DESM provided diethyl (E)-2-ethyl-2-(1-iodo-1-penten-5-yl)malonate (11). The condensation of functionalized malonates 3, 4, and 11 with urea in the presence of a base provided the corresponding barbiturates, 5-ethyl-5-(1-pentyn-5-yl)-(5), 5-ethyl-5-propargyl- (6), and (E)-5-ethyl-5-(1-iodo-1-penten-5-yl)barbituric acid (12), respectively. (E)-6-(Ethoxycarbonyl)-1-iodo-1-octene-6-carboxylic acid (13) was isolated as the hydrolytic byproduct of 11. Compound 13 decarboxylated under vacuum to provide ethyl (E)-1-iodo-1-octene-6-carboxylate (14). The 125I-labeled congeners of 12 and 13 were synthesized in the same manner and evaluated in rats. The barbiturate 12 exhibited significant brain uptake (approximately 1% dose after 5 min), demonstrating that iodinated barbiturates freely cross the intact blood-brain barrier

  2. Potential cerebral perfusion agents: synthesis and evaluation of a radioiodinated vinylalkylbarbituric acid analogue

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, P.C.; Callahan, A.P.; Cunningham, E.B.; Knapp, F.F. Jr.

    1983-05-01

    A new iodinated barbiturate has been prepared. Treatment of 5-chloropentyne and propargyl bromide with diethyl 2-ethyl-2-sodiomalonate (DESM) provided diethyl 2-ethyl-2-(1-pentyn-5-yl)malonate (3) and diethyl 2-ethyl-2-propargylmalonate (4), respectively. Similar condensation of DESM with (E)-(5-iodo-1-penten-1-yl)boronic acid (9) or the reaction of catecholborane with 3 provided diethyl (E)-2-ethyl-2-(1-borono-1-penten-5-yl)malonate (8). The direct sodium iodide-chloramine-T iodination of 8 or the treatment of (E)-1,5-diiodo-1-pentene (10) with DESM provided diethyl (E)-2-ethyl-2-(1-iodo-1-penten-5-yl)malonate (11). The condensation of functionalized malonates 3, 4, and 11 with urea in the presence of a base provided the corresponding barbiturates, 5-ethyl-5-(1-pentyn-5-yl)-(5), 5-ethyl-5-propargyl- (6), and (E)-5-ethyl-5-(1-iodo-1-penten-5-yl)barbituric acid (12), respectively. (E)-6-(Ethoxycarbonyl)-1-iodo-1-octene-6-carboxylic acid (13) was isolated as the hydrolytic byproduct of 11. Compound 13 decarboxylated under vacuum to provide ethyl (E)-1-iodo-1-octene-6-carboxylate (14). The /sup 125/I-labeled congeners of 12 and 13 were synthesized in the same manner and evaluated in rats. The barbiturate 12 exhibited significant brain uptake (approximately 1% dose after 5 min), demonstrating that iodinated barbiturates freely cross the intact blood-brain barrier.

  3. Development and evaluation of a magnetic solid-phase radioimmunoassay for total human thyroxine (T4)

    International Nuclear Information System (INIS)

    In this study a simple and rapid magnetic solid-phase radioimmunoassay (RIA) for human thyroxine (T4) was developed using locally raised sheep thyroxine antibody and radioiodinated thyroxine (T4) tracer by chloramine-T method. The assay involves two hours incubation at ambient temperature rang (30 to 35 oC) associated with the antibody covalently linked by the easily performed carbonyldiimidazole (CDI) method to magnetic particles obtained from SIPAC. 0.1% triton with sodium azide used as a wash buffer. L-Thyroxine Na-salt peta hydrate from sigma was used for the preparation of standards and quality control sera. The coupled magnetic anti-T4 solid phase titrated in order to find out the suitable antibody concentration (titre) to be used in the assay. Optimizations followed by validation procedures were done. When correlated with kits imported from NETRIA and AMERSHAM, results were found to be highly comparable r=0.965 and p<0.05. Shelf life was also studied, so that the local prepared T4 RIA magnetic reagents can be used for the measurement of total human thyroxine with a very low cost compared to imported kits. (Author)

  4. Radioimmunoassay for determination of alpha subunit of pituitary glycoprotein hormones in patients with pituitary tumors

    International Nuclear Information System (INIS)

    A radioimmunoassay method for alpha subunit has been described and applied for serum alpha subunit determinations in normal subjects and 71 patients with pituitary tumors /45 acromegalic and 26 non-acromegalic/. The labelling of alpha subunit by the chloramine T technique yielded 125I-alpha subunit of high specific activity and high immuno-reactivity. Three purification methods of labelled 125I-alpha subunit were compared; the best separation of undamaged 125I-alpha subunit from impurities was achieved by gel filtration on Ultrogel AcA54 column, whereas gel filtration on Sephadex G-100 and adsorption chromatography on CF-11 cellulose gave less satisfactory results. Microheterogenity of 125I-alpha subunit was disclosed by chromatofocusing on PBE 94; the fractions of high immunoreactivitiy had isoelectric points of 6.0, 5.5 and 4.8. In normal subjects, radioimmunoassay of alpha subunit gave the following results /mean and SD/: 0.75 ng/ml +- 0.41 in males and 0.80 ng/ml +- 0.39 in females in reproductive age. In 9 acromegalic serum alpha subunit concentration were elevated up to 21 ng/ml, and in 8 non-acromegalic up to 30 ng/ml. One woman with acromegaly and high serum alpha subunit concentration had also elevated serum TSH associated with hyperthyroids. Our results disclosed that high serum alpha subunit concentration occurs in 25 % of patients with pituitary adenomas. (Author)

  5. Development and clinical application of human gastrin radioimmunoassay

    International Nuclear Information System (INIS)

    The determination of human gastrin levels in the blood is very important for diagnosis of gastrointestinal disorders. This work describes the radioimmunoassay of gastrin developed according to Russell et al. and its clinical application measuring fasting levels of this hormone in normal subjects, gastrectomized, chagasics, patients with chronic renal failure (CRF), pernicious anemia (PA) and Zollinger-Ellison syndrome (ZES). Synthetic human gastrin was used for radioiodination and as standard, while the specific antibody was raised in rabbits. Gastrin was radioiodinated by a modification of the chloramine T technique and purified by anion exchange chromatography in QAE-Sephadex A-25 to a specific activity around 200 uCi/ug. The assays were performed by incubation of 125I-gastrin, standard gastrin (zero to 500 pmol/l) or unknown samples with the antiserum for 4 days at 40C. The antibody bound and free 125 I-gastrin was separated by adsorption of the latter to the charcoal. The basal gastrin values of normal subjects ranged from 2 to 74 pmol/l, being these levels higher in the chagasics (from 6 to 261 pmol/l). Higher levels of gastrin were determined in patients with CRF (from 12 to 350 pmol/l), PA (from 160 to 680 pmol/l) and with ZES(1010 pmol/l), while very low levels were confirmed in gastrectomized (from 1 to 8 pmol/l). (author)

  6. IRMA for assessment of soluble platelet glycocalicin and its clinical application in coronary heart disease

    International Nuclear Information System (INIS)

    Objective: To establish the immunoradiometric assay (IRMA) method for assessment of soluble platelet glycocalicin (sGC) and its clinical use. Methods: The labeling of 125I-2D4 was by chloramine T method. IRMA method was established for assessment of sGC. The plasma sGC levels of 50 healthy mine T method. IRMA method was established for assessment of sGC. The plasma sGC levels of 50 healthy people, 15 unstable angina (UA) and 37 acute myocardial infraction (AMI) were measured by IRMA. Results: The assaying range was 31.25-2000 μg/L. The sensitivity was 15 μg/L. The intra assay coefficients of variation (CV) were 6.25%, 4.35% and 3.99% (n=6) and the inter assay CV were 8.55%, 4.82% and 4.48% for 50, 300, 1800 μg/L, respectively. The average recovery rate was 101/88%. The plasma sGC level in normal group was (824.50 ± 225.11) μg/L. The plasma sGC levels in both UA and AMI groups were significantly higher than that in normal group (P<0.01). Coxregression analysis revealed that sGC was significantly correlated with P-selectin in AMI and UA groups (r=0.652, P<0.01). Conclusion: The sGC may be an important molecular marker of platelet activation and destruction. (authors)

  7. Comparison of three radioligands, selenium-75, iodine-125, and tritium, in the radioimmunoassay of methotrexate

    International Nuclear Information System (INIS)

    Radioimmunoassays for methotrexate are described, involving use of a rabbit antiserum to a conjugate of the drug and bovine serum albumin and the drug labeled with tritium, selenium-75, or iodine-125. Of the two gamma emitters, the 75Se-labeled drug was prepared by the Radiochemical Centre, Amersham, England and the 125I-labeled drug in the laboratory, by the Chloramine T iodination technique. The stability of labels with both methods allows use of the faster, cheaper, and simpler gamma-counting techniques, with results available after 3 h. All three methods have acceptable sensitivity, accuracy, precision, and reproducibility, and are specific for methotrexate, with no significant interference from naturally occurring folates or leucovorin. The assays in which the gamma emitters are used have significant practical advantages over the beta emitter and are much better suited to automation and clinical application. The main advantage of 75Se-labeled methotrexate is its longer half-life, 121 days, as compared with 60 days for 125I

  8. Development of Solid Phase Radioimmunoassay for Measuring Methotrexate and 7-Hydroxy Methotrexate in Biological Fluids using Magnetizable Particles

    International Nuclear Information System (INIS)

    The objective of the present study was to prepare a solid phase magnetic particles radioimmunoassay (RIA) reagents. Development as well as optimization and validation of RIA system for the assessment of methotrexate (MTX) and its main metabolite 7-hydroxy methotrexate (7-OH MTX) in human serum were described. Preparation of 125 I-MTX and 125 I -7(OH) MTX were carried out using tyrosine methyl ester (TME) and chloramine-T (Ch-T) as oxidizing agent. HPLC column was used for purification of the prepared tracers. The production of polyclonal anti - bodies was carried out using six rabbits divided to two groups. The first one was immunized intraperitoneal through primary injection and three booster doses using MTX-BSA conjugate while the other group was immunized using 7(OH) MTX-BSA conjugate. Low density magnitizable cellulose iron oxide particles have been used to couple covalently to polyclonal antibody. The results obtained provide a low cost, simple, sensitive, specific, and accurate RIA system based on magnetizable solid phase separation.

  9. The metabolism of parathyroid hormone in kidney

    International Nuclear Information System (INIS)

    In order to investigate the mechanism and localization of parathyroid hormone (PTH), the degradation and the effects of calcium ion to PTH degradation in kidney, bovine PTH (b-PTH 1 - 84) and its synthetic N-terminal peptide (b-PTH 1 - 34) labeled with 125I by Chloramine T methods (125I-b-PTH 1 - 84 and 125I-b-PTH 1 - 34) or labeled with horse radish peroxidase (125I-POX-b-PTH 1 - 84 and 125I-POX-bPTH 1-34) were used to study the disappearance from the blood stream and degradation and retention in the kidney after intravenous injections in male Wistar rats, weighing approximately 350 - 450 g. Degradation of PTH was studied in vitro, using isolated cells and homogenates of the kidney, and the effects of calcium ion to PTH degradation were furthermore studied, using our kidney perfusion system. PTH labeled with 125I and POX was less degraded by the kidney than PTH labeled with 125I alone. PTH 1 - 34 was more delayed in blood stream than PTH 1 - 84. Isolated intact kidney cells degrade PTH less efficiently than homogenates, indicating the prominance of microsomal degradative system in the kidney. The degradation of PTH in kidney was supposed to be controlled by calcium ion in our kidney perfusion system. (author)

  10. Galanin inhibits acetylcholine release in the ventral hippocampus of the rat: histochemical, autoradiographic, in vivo, and in vitro studies

    International Nuclear Information System (INIS)

    A high density of galanin binding sites was found by using 125I-labeled galanin, iodinated by chloramine-T, followed by autoradiography in the ventral, but not in the dorsal, hippocampus of the rat. Lesions of the fimbria and of the septum caused disappearance of a major population of these binding sites, suggesting that a large proportion of them is localized on cholinergic nerve terminals of septal afferents. As a functional correlate to these putative galanin receptor sites, it was shown, both in vivo and in vitro, that galanin, in a concentration-dependent manner, inhibited the evoked release of acetylcholine in the ventral, but not in the dorsal, hippocampus. Intracerebroventricularly applied galanin fully inhibited the scopolamine stimulated release of acetylcholine in the ventral, but not in the dorsal, hippocampus, as measured by the microdialysis technique. In vitro, galanin inhibited the 25 mM K+-evoked release of [3H]acetylcholine from slices of the ventral hippocampus, with an IC50 value of ≅ 50 nM. These results are discussed with respect to the colocalization of galanin- and choline acetyltransferase-like immunoreactivity in septal somata projecting to the hippocampus

  11. Development of 123I-labelled NNC 13-8241 as a radioligand for SPECT visualization of benzodiazepine receptor binding

    International Nuclear Information System (INIS)

    [125I]- and [123I]NNC 13-8241 were prepared from the trimethyltin precursor and radioactive iodide using the chloramine-T method. The total radiochemical yields of [125I]- and [123I]NNC 13-8241 were 60-70% and 40-50% respectively, with radiochemical purity higher than 98%. In binding studies with [125I]NNC 13-8241 in rats in vitro and in vivo a high uptake of radioactivity was demonstrated in brain regions known to have a high density of benzodiazepine (BZ) receptors such as the occipital and frontal cortex. SPECT examination with [123I]NNC 13-8241 in a Cynomolgus monkey demonstrated a high uptake of radioactivity in the occipital and frontal cortex. After displacement with flumazenil radioactivity in these brain regions was reduced to the level of a central region including the pons. Four hours after injection about 80% of the radioactivity in monkey plasma represented unchanged radioligand. This low degree of metabolism indicates that NNC 13-8241 is metabolically more stable than the radioligands hitherto developed for imaging of BZ-receptors in the primate brain

  12. Biologically active monoiodinated alpha-MSH derivatives for receptor binding studies using human melanoma cells

    International Nuclear Information System (INIS)

    Three different monoiodinated radioligands of alpha-MSH (alpha-melanocyte-stimulating hormone) were compared in a binding assay with human D10 melanoma cells: [Tyr(125I)2]-alpha-MSH, [Tyr(125I)2,NIe4]-alpha-MSH, and [Tyr(125I)2,NIe4,D-Phe7]-alpha-MSH. They were prepared either by the classical chloramine T method or by the Enzymobead method. A simple and rapid purification scheme was developed consisting of a primary separation on reversed-phase C18 silica cartridges immediately after the iodination, followed by HPLC purification before each binding experiment. Biological testing of the three radioligands showed that they all retained high melanotropic activity in the B16 melanin assay and the Anolis melanophore assay. However, in human D10 melanoma cells, [Tyr(125I)2,NIe4]-alpha-MSH led to a high degree of non-specific binding to the cells which could not be displaced by excess alpha-MSH and only partially by [NIe4]-alpha-MSH. The [Tyr(125I)2,NIe4,D-Phe7]-alpha-MSH tracer gave similar results but with a much lower proportion of non-specific binding. On the other hand, [Tyr(125I)2]-alpha-MSH proved to be an excellent radioligand whose non-specific binding to the D10 cells was not higher than 20% of the total binding

  13. Iodine-123 labeled derivatives of methylphenidate: potential SPECT radiopharmaceuticals for brain dopamine transporters

    Energy Technology Data Exchange (ETDEWEB)

    Pan, D.; Gatley, S.J.; Chen, R.; Ding, Y.-S. [Brookhaven National Lab., Upton, NY (United States)

    1996-06-01

    Since dl-threo-[{sup 11}C]methylphenidate (Ritalin) and especially the more active enantiomer, d-threo-[{sup 11}C]methylphenidate, have favorable properties for PET studies, we prepared two radioiodinated analogs of methylphenidate, p-[{sup 123}I]iodomethylphenidate and m-[{sup 123}I]iodo-p-hydroxymethylphenidate with a view to evaluating them as potential SPECT tracers. To prepare p-[{sup 123}I]iodomethylphenidate, the p-tributyltin derivative was prepared from the previously reported p-bromomethylphenidate and reacted under acidic conditions with I-123 iodide plus chloramine-T at room temperature for 90 seconds. The predomimant radioactive product was obtained in 85% radiochemical yield and > 10 Ci/{mu}mol specific radioactivity after HPLC purification. It had the same HPLC retention time as a spectroscopically characterized non-radioactive p-iodomethylphenidate standard prepared via nitration of methylphenidate and diazotization, after protection of the secondary amino group by benzoylation. A second radioiodinated methylphenidate derivative, m-[{sup 123}I]iodop-hydroxymethylphenidate was prepared in 80% radiochemical yield by direct iodination of the known p-hydroxymethylphenidate. In this case the non-radioactive standard was prepared by iodination of p-hydroxyritalinic acid using I{sub 2} and iodic acid, followed by esterification. (author).

  14. Radioimmunoimaging of ovarian cancer with 131I labelled CEA monoclonal antibody

    International Nuclear Information System (INIS)

    Objective: To investigate radioimmunoimaging with 131I labelled CEA McAb and its value in diagnosis and treatment of ovarian cancer. Methods: CEA McAb was labelled with 131I by standard chloramine T procedure. The radiolabeled McAb was given intravenously to the patients. The scintigraphy was performed at different time. Results: In 105 patients with histopathology proved ovarian cancers, for 96 patients the lesions were well located with RII (true positives), for the remaining 9 patients, the results were false negative. 22/23 cases with RII diagnosed benign ovarian tumors were proved to be true negative by surgical pathology in RII. Of 96 ovarian cancers 87 were stratified into identical stages by surgical pathology all RII. 141/151 metastatic tumors were found in RII and the positive rate was as high as 93.4%. The smallest tumor defected by RII was of 1 cm in diameter. Conclusions: RII is as good as ultrasonography and CT in distinguishing benignancy and malignancy. The location, size and number of the lesions can also be determined with RII. RII of ovarian cancer with 131I-CEA McAb is valuable and helpful in early detection of ovarian cancer. It is also helpful for clinical staging, treatment programing and prognosticating

  15. Preparation, purification and primary bioevaluation of radioiodinated ofloxacin. An imaging agent

    International Nuclear Information System (INIS)

    The broad-spectrum antibiotic agents have been demonstrated as promising diagnostic tools for early detection of infectious lesions. We set out ofloxacin (Oflo), a second-generation fluoroquinolone, for the radioiodination process. In particular, this was carried out with 125I via an electrophilic substitution reaction. The radiochemical yield was influenced by different factors; drug concentration, different oxidizing agents, e.g. chloramine-T, iodogen and n-bromosuccinimide, pH of medium, reaction time, temperature and different organic media. These parameters were studied to optimize the best conditions for labeling with ofloxacin. We found that radiolabeling in ethanol medium showed a 70% radiochemical yield of 125I-ofloxacin. The radioiodination was determined by means of TLC and HPLC. The cold labeled Oflo (127I-Oflo) was prepared and controlled by HPLC. The cold labeled Oflo was also confirmed by NMR and MS techniques. Furthermore, biodistribution studies for labeled 125I-Oflo were examined in two independent groups (3 mice in each one); control and E. Coli-injected (inflamed). The radiotracer showed a good localization in muscle of thigh for inflamed group as compared to control. In conclusion, ofloxacine might be a promising target as an anti-inflammatory imaging agent.

  16. Kinetic and Mechanistic Studies of Oxidation of an Antiallergic Drug with Bromamine-T in Acid and Alkaline Media

    International Nuclear Information System (INIS)

    Cetrizine dihydrochloride (CTZH) is widely used as an anti-allergic drug. Sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) is the bromine analogue of chloramine-T (CAT) and is found to be a better oxidizing agent than CAT. In the present research, the kinetics of oxidation of CTZH with BAT in acid and alkaline media was studied at 313 K. The experimental rate laws obtained are: -d[BAT]/dt = k[BAT] [CTZH]0.80[H+]-0.48 in acid medium and -d[BAT]/dt = k[BAT][CTZH]0.48[OH-]0.52[PTS]-0.40 in alkaline medium where PTS is p-toluenesulfonamide. Activation parameters and reaction constants were evaluated. The solvent isotope effect was studied using D2O. The dielectric effect is positive. The stoichiometry of the reaction was found to be 1:1 and the oxidation products were identified as 4-chlorobenzophenone and (2-piperazin-1-yl-ethoxy)-acetic acid in both media. The rate of oxidation of CTZH is faster in acid medium. Suitable mechanisms and related rate laws have been worked out

  17. A general method for the production of 125I-labelled low-molecular-weight tracers for radioimmunoassay

    International Nuclear Information System (INIS)

    A general method is described for the separation of low-molecular-weight 125I-labelled tracers from a chloramine-T labelling mixture, containing the starting material, the tracer, labelled by-products, free radioiodine and reagents used in the labelling procedure. Small molecules like tyrosine, thyronine and steroids as well as their tyrosine methyl ester conjugates are adsorbed on Sephadex LH-20 dextran gel. The introduction of iodine atoms increases the elution volume and the distribution coefficient in proportion to the number of iodine atoms per molecule. Organic solvents like ethanol are also adsorbed on dextran gel, which results in desorption of the starting material or its iodine-substituted derivatives. The elution order follows the number of iodine substituents per molecule, i.e. unsubstituted starting material, mono-, di-, tri- and tetra-substituted molecules. Using a water/ethanol binary eluent in which water can be considered as inert diluent, the elution is governed by the ethanol concentration. The finding that the logarithm of the distribution coefficient of the solutes is linearly correlated with the logarithm of the ethanol concentration permits an optimization of the separation. (author)

  18. Studies into the radiobromination and -iodination of aromatic compounds with n-halogen compounds without addition of carriers

    International Nuclear Information System (INIS)

    There is a special need for radiohalogenated compounds for diagnostic nuclear medicine, in particular for no-carrier-added (nca) short lived cyclotron products. In this study the applicability of chloramine-T (CAT) and dichloramine-T (DCT) has been demonstrated for nca-radiohalogenation with bromine-75, 77 and iodine-123 in aqueous and organic solvents. Radio gaschromatography and -HPLC are used for product analysis. In aqueous solution the optimum reaction conditions with respect to pH, concentration of CAT, reaction time and added bromide-carrier are determined using tyrosine as a model substrate. The suitability of the CAT method for radiobrominations under convenient and mild conditions is demonstrated for some biomolecules such as amino acids and nucleobases as well as for peptides and the proteins urokinase and HSA. Dichloramine-T is found to be a new efficient reagent for radiobromination and -iodination of aromatic compounds in various organic solvents such as acetic acid, dichloromethane or carbontetrachloride. A high para-selectivity is observed and the radiochemical yields (80%) are as high as in aqueous solution. A comparison of this reagent with different in-situ halogenation agents show that DCT is superior with respect to reaction time, concentration of the reagent and thus oxidative side reactions, and ease of handling. (orig./RB)

  19. Solid phase group specific absorbants in assays for glycoproteins

    International Nuclear Information System (INIS)

    The focus of this paper is on several technical advances in the assays for glycoprotein hormones and enzymes that have been achieved by use of the solid phase carbohydrate specific adsorbant concanavalin-A. Puriffication of glycoprotein radioligand after labelling by the chloramine-T method is readily accomplished using a small column of agarose bound concanavalin-A which separates glycoprotein radioligand from radioiodide and radiolabelled unadsorbed contaminants. After concanavalin-A column chromatography, radiolabelled glycoprotein hormone preparations exhibited improved binding to antibodies and tissue receptors. To increase the effective sensitivity of radioimmunoassays for glycoproteins, agarose bound concanavalin-A is used to extract and concentrate the glycoproteins from various biologic samples. For example, the effective sensitivity for the detection of human thyrotropin in serum was improved approximately 5 fold by using concanavalin-A concentrates of 1.5 ml of serum. Partial purification of the glycoprotein dopamine-β-hydroxylase from serum using agarose bound concanavalin-A resulted in separation of the serum factors that interfere with the measurement of enzyme activity. We conclude that in assays for glycoproteins, concanavalin-A is useful for purification of radioligand, for preparation of concentrates of glycoproteins from biologic samples, and for separation of glycoproteins from various interfering factors contained in biologic samples prior to radioligand or radioenzyme assay. (orig.)

  20. Solid-phase group-specific adsorbants in assays for glycoproteins

    International Nuclear Information System (INIS)

    The focus of the paper is on several technical advances in the assays for glycoprotein hormones and enzymes that have been achieved by the use of the solid-phase cabohydrate-specific adsorbant concanavalin-A. Purification of glycoprotein radioligand after labelling by the Chloramine-T method is readily accomplished using a small column of agarose-bound concanavalin-A which separates glycoprotein radioligand from radioiodide and radiolabelled unadsorbed contaminants. After concanavalin-A column chromatography, radiolabelled glycoprotein hormone preparations exhibited improved binding to antibodies and tissue receptors. To increase the effective sensitivity of radioimmunoassays for glycoproteins, agarose-bound concanavalin-A is used to extract and concentrate the glycoproteins from various biological samples. For example, the effective sensitivity for the detection of human thyrotropin in serum was improved approximately 5-fold by using concanavalin-A concentrates of 1.5ml of serum. Partial purification of the glycoprotein dopamine-β-hydroxylase from serum using agarose-bound concanavalin-A resulted in separation of the serum factors that interfere with the measurement of enzyme activity. We conclude that in assays for glycoproteins, concanavalin-A is useful for purification of radioligand, for preparation of concentrates of glycoproteins from biological samples and for separation of glycoproteins from various interfering factors contained in biological samples before radioligand or radioenzyme assay. (author)

  1. 125I Labelling of Protein Using Immobilized Enzyme

    International Nuclear Information System (INIS)

    For an effective solid-phase labelling of protein with 125I, studies on the immobilization of lactoperoxidase (LPO) on the inner wall of polystyrene tubes were carried out. Labelling of bovine serum albumin (BSA) and insulin was also practiced using the LPO immobilized tubes. The immobilized enzyme of about 2.5 μ g/tube was sufficient for small scale labelling since the results of radio-paper chromatography of the labelling mixture of insulin indicated that the yields were sufficiently high (80%) even in the reactions conducted at room temperature for 60 sec. The results of the Sephadex column chromatography indicated that the labelled products were not contaminated with LPO-125I, and the radiochemical purity of the products was more than 90%. In considering the general trend that the 125I labelled protein obtained by using LPO maintains its intactness better than those obtained by using chloramine-T, together with the tendency of yield enhancing with increase of reactants-concentration, the LPO immobilized tube method is estimated to be one of the simple methods of labelling. The product might be applicable without further purification.

  2. Experimental research for tumor VIP receptor imaging

    International Nuclear Information System (INIS)

    To study the possibility of radioactive labelled vasoactive intestinal peptide (VIP) for tumor VIP receptor imaging. 125I-VIP was prepared by chloramine-T method, and purified by Sephadex G-50 column chromatography. The bioactivity and stability of 125I-VIP were measured by silica 60 F254 TLC and competition test to SGC7901 cell in vitro. The biodistribution of 125I-VIP was studied in the nude mice bearing tumor. The results showed that labelled rate of 125I was 73.8%, the specific activity was 18.2 PBq/mol, the radiochemical purity (RCP) was over 98% and remained 96.3% after 48 days stored at -80 degree C. The specific binding of 125I-VIP to the SGC7901 cell was inhibited by VIP in dose dependence in the competition experiment. The radioactivity of tumor was higher than that of muscles in all phases (P<0.05-0.01), the peak activity of tumor occurred at 30 min (3.58 +- 0.48ID%/g) and the peak ratio of T/N occurred at 60 min after the injection. The activity of lungs was obviously higher than that of blood, the intestine was always in low level. Most of the activity in the body was mainly eliminated from kidney. The present study demonstrated that the radioactive labelled VIP is a promising agent for tumor VIP receptor scintigraphy

  3. Radioactive Iodo-azathioprine as a possible model for cancer imaging and therapy

    International Nuclear Information System (INIS)

    Azathioprine (Aza) is antimetabolite drug, could be labeled with the auger emitters iodine-125. Aza could be used an ideal vehicle to deliver radioactive decay energy to DNA of tumor cells causing DNA double strand break, thus stop DNA synthesis. In this study, the process of labeling was done via direct labeling technique using chloramine-T as an oxidizing agent and heating to 75 degree C, for 30 minutes at ph using 0.5 M phosphate buffer. The radiochemical purity of the labeled compound, at the above conditions, was determined using electrophoresis technique and was above 90%. About 2.5x106 of enrich ascites carcinoma (EAC) was injected intraperitoneally(i.p) to produce ascites and intramuscularly (i.m) in the right thigh to produce solid tumor in female mice. Biodistribution studies were carried out by injecting solution of 125I-aza in normal and tumor bearing mice. The uptake in ascites was over 40 % of the injected dose at 12 h post injection and above 20 % in solid tumor . These data revealed localization of the tracer in the tumor tissues with high percentage sufficient to give radiotherapeutic effect as well as promising tool for diagnosis.

  4. Preparation of 125I labelled nerve growth factor and study of its pharmacokinetics

    International Nuclear Information System (INIS)

    125I-Nerve growth factor (125I-NGF) with more than 95% of radiochemical purity is prepared by chloramine-T method. After I.V. and I.M. injection of 125I-NGF, pharmacokinetics of NGF in mice is determined by SDS-PAGE method. The results show that concentration-time curves after I.V. injection are fitted to a 2-compartment model are those after I.M. injection are fitted to a 1-compartment model. After I.V. injection of 25 μg/kg, the elimination half life (t1/2(β)) is 3.65 h. After I.M. injection of 75, 25, 10, 3.3 μg/kg, t1/2(β) is 1.79, 2.25, 2.30, 3.24 h, respectively. The mean plasma clearance (CLs) is 0.37 L/(h·kg), the appearance volume of distribution (Vd) is 1.18 L/kg and the mean residence time (tr-bar) in mice is 2.78 h. The pharmacokinetics of 125I-NGF in mice is useful for clinical trial

  5. Development of a radioimmunoassay for the measurement of human leptin in serum

    International Nuclear Information System (INIS)

    Leptin is a 16 kDa polypeptide hormone encoded by the obese gene (ob) and secreted by adipose tissue. This hormone plays a major role in energy homeostasis and regulation of food intake and body weight. It also affects the metabolic, neuroendocrine and reproductive systems. Labelling of recombinant human leptin with 125I was best performed by the Chloramine-T method. New Zealand white rabbits were immunised with recombinant human leptin, cross-reaction of obtained antisera was analyzed with 10 different antigens. The separation of bound and free fractions was performed using the second antibody - PEG method. The obtained tracer had specific activities of 2.8-3.3 kBq/μg and had a stability of 5 weeks. A highly specific polyclonal antibody was obtained without measurable cross-reaction against the analysed antigens. Concentrations of human leptin were measured by a single overnight incubation assay with a sensitivity of 0.5 ng/ml and a measuring range of 0.5-100 ng/ml. The intra-assay and inter-assay coefficient of variation was under 6% and 8%, respectively. Recovery ranged from 88% to 106%. Serum human leptin concentrations can be accurately and precisely measured by this new radioimmunoassay. Preliminary results obtained from the measurement of serum leptin in lean, overweight and obese patients are presented. Serum leptin concentrations correlated with body mass index and were significantly higher in women than in men, except for obese patients. (author)

  6. Development of radioimmunoassay for human leptin and its primary clinical application

    International Nuclear Information System (INIS)

    Leptin was a hormone synthesized and secreted by lipid cells which encoded and expressed by the obese gene. In this article, rabbit-anti-human leptin polyclonal antibodies (PcAb) was prepared by immunizing rabbits with recombined human leptin while 125I-leptin was obtained by chloramines-T method. A method of RIA for human leptin was developed, using these self-made preparations. The result of tests showed high sensitivity and specificity with reliable reproducibility, which proved that the quality of our preparations was no less good than that of the imported Linco product. The normal range (BMI 18-25) was 2.15 ± 1.46 ng/mL (male, 34 cases) and 7.86 ± 3.60 ng/mL(female, 36 cases). There was significant positive correlation (r=0.72, P<0.001) between serum leptin concentrations and body-mass-index (BMI), in the case of 112 healthy persons were separated to male group and female group. Tere was no significant correlation between serum leptin concentrations and ages. So did follicle-stimulating hormone, luteinizing hormone, prolactin, progesterone and estradiol in females. But in males, serum leptin concentrations correlated directly and negatively with testosterone concentrations. (authors)

  7. Antiseptics and microcosm biofilm formation on titanium surfaces

    Directory of Open Access Journals (Sweden)

    Georgia VERARDI

    2016-01-01

    Full Text Available Abstract Oral rehabilitation with osseointegrated implants is a way to restore esthetics and masticatory function in edentulous patients, but bacterial colonization around the implants may lead to mucositis or peri-implantitis and consequent implant loss. Peri-implantitis is the main complication of oral rehabilitation with dental implants and, therefore, it is necessary to take into account the potential effects of antiseptics such as chlorhexidine (CHX, chloramine T (CHT, triclosan (TRI, and essential oils (EO on bacterial adhesion and on biofilm formation. To assess the action of these substances, we used the microcosm technique, in which the oral environment and periodontal conditions are simulated in vitro on titanium discs with different surface treatments (smooth surface - SS, acid-etched smooth surface - AESS, sand-blasted surface - SBS, and sand-blasted and acid-etched surface - SBAES. Roughness measurements yielded the following results: SS: 0.47 µm, AESS: 0.43 µm, SB: 0.79 µm, and SBAES: 0.72 µm. There was statistical difference only between SBS and AESS. There was no statistical difference among antiseptic treatments. However, EO and CHT showed lower bacterial counts compared with the saline solution treatment (control group. Thus, the current gold standard (CHX did not outperform CHT and EO, which were efficient in reducing the biofilm biomass compared with saline solution.

  8. The use of protein A in solid-phase binding assays: a comparison of four radioiodination techniques

    International Nuclear Information System (INIS)

    Preparations of protein A radioiodinated by 4 different methods have been compared in indirect radioimmunoassays. The oxidative methods (chloramine-T and iodogen) for direct iodination of tyrosyl and histidyl residues were applied with high efficiency and gave a suitable product, provided the substitution ratio was kept low (1 iodine atom/molecule of protein A). Higher levels of modification tended to perturb the Fsub(c)-binding characteristics of the protein, especially with the use of iodogen. Introduction of the isotope via substitution of lysyl residues (Bolton-Hunter and Wood reagents) was also examined. The Bolton-Hunter modification of protein A gave an unsuitably low labelling efficiency: in contrast, the Wood reagent gave efficiencies approaching 50%. Protein A could be extensively substituted with the latter reagent (>5 diiodinated benzimidate molecules per protein molecule). Thus, the use of the Wood-labeled protein A could raise the sensitivity of the binding assay at least an order of magnitude compared to using protein A iodinated by the oxidative methods. The effects on the biological activity of protein A exerted by the different labeling procedures are rationalized on the basis of the amino acid composition and tertiary structure of the protein. (Auth.)

  9. Studies on porcine pancreatic elastase activity, 1

    International Nuclear Information System (INIS)

    An improved method of radioimmunoassay was devised to offer a successful formula for determining blood concentration of elastase. With porcine pancreatic elastase as the antigen, rabbits were immunized to obtain antiserum. Iodinated elastase labeled by the chloramine-T procedure using 131I (or 125I) had a specific activity of 200 - 300 mCi/mg. The double antibody method was used for BF separation. While the usual method of radioimmunoassay was not always successful in obtaining accurate serum concentration of elastase, the use of diisopropyl fluorophosphate (DFP) was able to eliminate the disturbing influence of intra-serous inhibitors, α1-AT and α2-M, eventually producing satisfactory results. With the use of DFP, the elastase standard curve and the porcine serum dilution curve had a statistically significant correlation; precision and recovery were both satisfactory; cross-reactivity of the antiserum with trypsin and chymotrypsin was less than 0.001%. The minimal detectable concentration of elastase was 5 ng/ml, and the range of normal fasting porcine serum level was 70 - 100 ng/ml. (author)

  10. Production of antibodies against secretin and their use for radioimmunoassay of secretin

    International Nuclear Information System (INIS)

    Synthetic thyroglobulin was bonded to bovine albunia and thyroglobulin according to the principle of the carbodiimide condensation reaction. 16 rabbits were immunized with these conjugates and with unconjugated secretin. Secretin labelling with 125I was carried out by the chloramin-T method. The tracer has a specific activity of 15.45 mCi/mg. A secretin RIA was developed using the double antibody method. The sensitivity of the system could be raised by variation of the specific activity of the tracer and optimisation of the incubation parameters. Antisera were compared. The titers of secretin/bovine albumine conjugate antisera were similar to the antisera against secretin thyroglobulin conjugate. The sensitivity of the standard curves was higher for secretin/bovine albumin conjugate antisera than for thyroglobulin conjugate antisera. Two antisera were tested for specificity. The detection threshold of antiserum S 5 IX was 12,43 pmol/l while the 50% intercept was at 55.45 pmol/l. This antiserum is particularly suitable for a secretin RIA. (orig./MS)

  11. Therapeutic effect of 131I-histamine-indomethacin in mice with Lewis pulmonary tumor

    International Nuclear Information System (INIS)

    Histamine-indomethacin (HIS-IN) was labeled with 131I by chloramine-T method. Thin-layer chromatography (TLC) was performed to evaluate the labeling ratio, radiochemical purity and stability of 131I-HIS-IN, using silicagel GF254 coated on glass plates, with chloroform and methanol being the mobile phase. The biodistributions of 131I-HIS-IN in Lewis pulmonary tumor model mice and normal mice were examined, and therapeutic effect of 131I-HIS-IN on mice with Lewis pulmonary tumor was studied. The results showed that radiochemical purity of the 131I-HIS-IN was 98%, and the highest %ID·g-1 of tumor tissue was 4.73±0.07 at 4 h, while the tumor/blood ratios were 2.95±0.30 at 8 h, 2.67±0.62 at 12 h and 3.54±0.54 at 16 h. The ratios, and the necrotic tissue cells, increased with the post-injection hours. Therefore, 131I-HIS-IN can be a new radioactive drug for tumor therapy. (authors)

  12. Luminal oxidants selectively modulate electrogenic ion transport in rat colon

    Institute of Scientific and Technical Information of China (English)

    Julio M Mayol; Yolanda Adame-Navarrete; Pilar Alarma-Estrany; Elena Molina-Roldan; Fernando Huete-Toral; Jesus A Fernandez-Represa

    2006-01-01

    AIM: To investigate the effects of luminal exposure to H2O2 and two related thiol oxidizing agents on basal and stimulated chloride secretion in native colon using electrophysiological and pharmacological approaches.METHODS: Unstripped rat distal colon segments were mounted in Ussing chambers. Potential difference, cal culated resistance and short-circuit current across unstripped colon segments were monitored with a dual voltage/current clamp. Paracellular permeability was assessed by measuring the mucosa-to-serosa flux of a fluorescent probe (FITC).RESULTS: Luminal exposure to hydrogen peroxide transitorily stimulated chloride secretion without altering barrier function. This stimulatory effect could be blocked by basolateral atropine but not indomethacin. The cysteine and methionine oxidizing compounds, phenylarsine oxide and chloramine T respectively, mimicked the effect of H2O2, except for a drop in transcolonic resistance after 30 min. In contrast to the observed stimulatory effect on basal secretion, cAMP-stimulated electrogenic ion trans port was blunted by luminal H2O2. However, the Ca2+-activated response remained unchanged.CONCLUSION: H2O2 may be an important selective modulator of intestinal ion and water secretion in certain pathologic conditions such as inflammation or ischemiareperfusion by multiple mechanisms.

  13. Labeling of polyamidoamine with 125I and its biodistribution in mice

    International Nuclear Information System (INIS)

    Objective: To investigate the biodistribution of 125I labeled dendrimer nanomaterial--polyamidoamine (PAMAM) in mice. Methods: Tyrosine was conjugated to four generation PAMAM by N-Hydroxysuccinimide,then 125I was labeled on PAMAM with chloramines-T method,and purified by dialysis. Labeling rate,radiochemical purity and stability of 125I-PAMAM were detected by radioactive thin layer chromatography scanning. The gamma imaging and biodistribution were detected by in vivo imaging system and gamma counter at one, four, eight, twenty-four and forty-eight hours after intravenous injection. Results: The 1H nuclear magnetic resonance results showed that about two tyrosines were conjugated to PAMAM. The 125I labeling rate was about 56% and radiochemical purity was more than 98%. The radiochemical purity of labeled compound remained more than 90% at 72 hours in vitro. In vivo imaging results showed that PAMAM was mainly accumulated in liver periphery. The gamma counter results showed that PAMAM mainly accumulated in liver, kidney and spleen, the excretion of PAMAM was slow and there has high dose of PAMAM in mice at 48 hours. Conclusion: PAMAM with no chemical modification was mainly accumulated in liver, kidney and spleen, and the excretion of PAMAM was slow, so PAMAM is not fit as drug carrier. PAMAM need to chemical modification to accelerate excretion and prevent the emergence of toxicity caused by accumulation in body. (authors)

  14. In vivo detection of prostatic carcinoma with antibodies against prostatic acid phosphatase

    International Nuclear Information System (INIS)

    Serum prostatic acid phosphates (PAP) immunoassay is used to evaluate patients with prostatic carcinoma; however, as with other tumor markers, the enzyme levels do not necessarily reflect the presence or extent of tumor. The authors investigated the use of radiolabeled PAP antibodies for the in vivo detection of prostatic carcinoma by external scintillation imaging. Nine patients with prostatic carcinoma were entered into the study. Each received from 2.0 to 2.5 mCi of I-131 labeled antibody to PAP, administered i.v. The immunogen (PAP) was purified from normal human seminal fluid. Antiserum was prepared in rabbits by injecting the purified PAP. The antibodies were labeled with I-131 by chloramine-T method (10 to 20 Ci/g of IgG). Total body images were obtained at 24 and 48 hrs following administration of the labeled antibody. Nontarget I-131 activity was diminished by computer processing. Tumor sites detected by I-131 antibodies were correlated with other diagnostic procedures. In 7 of 9 patients primary and metastatic sites of cancer were detected by antibody imaging, however, no bone lesions were detected (6 cases). In 3 patients with concomitant pulmonary tumors, one was identified as of prostate origin. The serum PAP was normal in 4 patients; however, the primary tumor was identified in 3 of these. These findings suggest that the localization of prostatic carcinoma by means of in-vivo imaging of labeled antibodies to PAP is feasible and offers diagnostic opportunities based upon the functional characteristics

  15. A pigeon crop sac radioreceptor assay for prolactin

    International Nuclear Information System (INIS)

    Ovine prolactin, labelled with 125I by either lactoperoxidase or a mild chloramine T method, was bound to receptors from the pigeon crop sac mucosa cells of prolactin-injected pigeons. Binding was demonstrated in a crude homogenate of mucosal cells removed from the crop by scraping and in a subcellular fraction in which 5'- nucleotidase activity was enhanced two- to three-fold. The binding was specific, dependent on time, temperature and the concentration of receptors and had a dissociation constant of 7 x 10-10 mol/l. The binding capacity of the crop tissue was 71 fmol/mg membrane protein. Nine purified preparations of prolactin from four species were assayed by local pigeon crop sac bioassay and by radioreceptor assay. The two methods were highly correlated (r = 0.934). The regression equation was radioreceptor assay = 1.22 bioassay - 0.18 indicating a 1:1 correspondence between the two methods for prolactin purified from sheep, rat, horse and pig anterior pituitary glands. (author)

  16. Radioimmunoassay measurement of secretin half-life in man

    International Nuclear Information System (INIS)

    High titer antibodies to secretin were produced in rabbits by immunization with purified porcine secretin (from GIH) conjugated to bovine serum albumin in complete Freund's adjuvant. Synthetic porcine secretin (from Squibb) was radiolabeled with 125I using chloramine-T and radiosecretin was purified using talc-silica and fibrocellulose powder. Specificity of antibodies to secretin was extensively evaluated in studies examining (1) cross-reactivity with other naturally occurring hormones, (2) parallelism of serum dilutions and secretin standards, (3) quantitative recovery of secretin added to serum samples, and (4) changes in circulating immunoreactive secretin in response to intraduodenal acidification. The mean fasting serum secretin concentration in 10 dogs was 65 +- 5 (SEM) pg per ml and in 21 healthy human volunteers it was 69 +- 5 pg per ml. In response to intraduodenal instillation of 10 mEq of HCl, portal venous secretin concentrations increased from a mean fasting value of 52 to 450 pg per ml within 2 min; peripheral venous secretin increased from 66 to 229 pg per ml within 5 min. No significant changes in peripheral serum immunoreactive secretin concentrations were identified in dogs after a protein meal. Intravenously administered secretin in man disappeared from the circulation with mean half-life 4.06 +- 0.82 (SEM) min

  17. Immunolocalization of neuroblastoma using radiolabeled monoclonal antibody UJ13A

    International Nuclear Information System (INIS)

    The monoclonal antibody UJ13A, raised after immunization of mice with human fetal brain, recognized an antigen expressed on human neuroblastoma cell lines and fresh tumors. Antibody was purified and radiolabeled with iodine isotopes using chloramine-T. In preclinical studies, 125I-labeled UJ13A was injected intravenously into nude mice bearing xenografts of human neuroblastoma. Radiolabeled UJ13A uptake by the tumors was four to 23 times greater than that by blood. In control animals, injected with a similar quantity of a monoclonal antibody known not to bind to neuroblastoma cells in vitro (FD44), there was no selective tumor uptake. Nine patients with histologically confirmed neuroblastoma each received 100 to 300 micrograms UJ13A radiolabeled with 1 to 2.8 mCi 123I or 131I. Sixteen positive sites were visible on gamma scans 1 to 7 days after injection: 15 were primary or secondary tumor sites, and one was a false positive; there were two false negatives. In two of the 15 positive sites, tumor had not been demonstrated by other imaging techniques; these were later confirmed as areas of malignant infiltration. No toxicity was encountered

  18. Dynamic behavior of histone H1 microinjected into HeLa cells

    International Nuclear Information System (INIS)

    Histone H1 was purified from bovine thymus and radiolabeled with tritium by reductive methylation or with 125I using chloramine-T. Red blood cell-mediated microinjection was then used to introduce the labeled H1 molecules into HeLa cells synchronized in S phase. The injected H1 molecules rapidly entered HeLa nuclei, and a number of tests indicate that their association with chromatin was equivalent to that of endogenous histone H1. The injected molecules copurified with HeLa cell nucleosomes, exhibited a half-life of ∼100h, and were hyperphosphorylated at mitosis. When injected HeLa cells were fused with mouse 3T3 fibroblasts < 10% of the labeled H1 molecules migrated to mouse nuclei during the next 48 h. Despite their slow rate of migration between nuclei, the injected H1 molecules were evenly distributed on mouse and human genomes soon after mitosis of HeLa-3T3 heterokaryons. These results suggest that although most histone H1 molecules are stably associated with interphase chromatin, they undergo extensive redistribution after mitosis

  19. Effects of combined 131I- and CT-BAC5 immunotherapy on NPC CNE-2 multicellular spheroids

    International Nuclear Information System (INIS)

    Objective: To develop a new specific therapeutic method for treating nasopharyngeal carcinoma (NPC) and to evaluate its effects on an in vitro tumor spheroid model. Methods: The human NPC cell line CNE-2 spheroids were grown in culture medium, on a thin layer of 0.75% agarose. The average volume of the spheroids was estimated by 1/2 (short dimension)2 x (long dimension). Anti-NPC BAC5 MAb was labelled with 131I using chloramine-T method. Cytotoxin from Chinese cobra (CT) was conjugated with BAC5 by hetero bifunctional cross-linking reagent (SPDP). The spheroids were treated with either 131I-BAC5 or CT-BAC5 separately or with both of them together by incubating in culture medium. Results: The conjugated rate of BAC5 and CT was 32.4%. CT-BAC5 significantly inhibited the growth of CNE-2 multicellular spheroids comparing with control agent (normal saline) (P 131I-BAC5 did more than CT-BAC5 (P131I-BAC5 with CT-BAC5 treatment showed even stronger destructive effect on the spheroids (vs. normal saline, P 131I-BAC5 with CT-BAC5 is better than either of them working separately

  20. Development and characterization of radioimmunoassay methods for the measurement of iodothyronines (T4, T3 and rT3)

    International Nuclear Information System (INIS)

    The experience acquired in the development of radioimmunoassay for T4, T3 and rT3 in unextrated serum is described. Antisera were produced in rabbits using iodothyronines conjugated to bovine serum albumin: the antisera selected provided the development of sensitive and specific radioassay methods. Stable high activity T3, T4 and rT3 tracers were prepared by iodination of 3,5 T2, T3 and 3,3' T2 by the chloramine-T method, and purified by column chromatography on Sephadex G25. Binding of those iodothyronines to endogenous serum proteins was blocked by including 8-aniline-1-naphtalene sulphonic acid (ANSA) in the T4 and T3 assays and thymerosal in the rT3 assay. Normal values were defined in 46 healthy euthyroid adults of both sexes: T4 = 7,1 +- 1,3μg/dl; T3 = 139 +- 35ng/dl and rT3 = 18,0 +- 7,9ng/dl. (Author)

  1. Selective mono-radioiodination and characterization of a cell-penetrating peptide. L-Tyr-maurocalcine

    Energy Technology Data Exchange (ETDEWEB)

    Ahmadi, Mitra; Bacot, Sandrine; Perret, Pascale; Riou, Laurent; Ghezzi, Catherine [Universite Joseph Fourier, Grenoble (France); INSERM U1039, Grenoble (France). Radiopharmaceutiques Biocliniques; Poillot, Cathy; Cestele, Sandrine [INSERM U836, Grenoble (France). Grenoble Inst. of Neuroscience; Universite Joseph Fourier, Grenoble (France); Desruet, Marie-Dominique [INSERM U1039, Grenoble (France). Radiopharmaceutiques Biocliniques; Couvet, Morgane; Bourgoin, Sandrine; Seve, Michel [CRI-INSERM U823, Grenoble (France). Inst. of Albert Bonniot; Universite Joseph Fourier, Grenoble (France); Waard, Michel de [INSERM U836, Grenoble (France). Grenoble Inst. of Neuroscience; Universite Joseph Fourier, Grenoble (France); Smartox Biotechnologies, Grenoble (France)

    2014-07-01

    Mono-and poly-iodinated peptides form frequently during radioiodination procedures. However, the formation of a single species in its mono-iodinated form is essential for quantitative studies such as determination of tissue concentration or image quantification. Therefore, the aim of the present study was to define the optimal experimental conditions in order to exclusively obtain the mono-iodinated form of L-maurocalcine (L-MCa). L-MCa is an animal venom toxin which was shown to act as a cell-penetrating peptide. In order to apply the current direct radioiodination technique using oxidative agents including chloramine T, Iodo-Gen {sup registered} or lactoperoxidase, an analogue of this peptide containing a tyrosine residue (Tyr-L-MCa) was synthesized and was shown to fold/oxidize properly. The enzymatic approach using lactoperoxidase/H{sub 2}O{sub 2} was found to be the best method for radioiodination of Tyr-L-MCa. MALDI-TOF mass spectrometry analyses were then used for identification of the chromatographic eluting components of the reaction mixtures. We observed that the production of different radioiodinated species depended upon the reaction conditions. Our results successfully described the experimental conditions of peptide radioiodination allowing the exclusive production of the mono-iodinated form with high radiochemical purity and without the need for a purification step. Mono-radioiodination of L-Tyr-MCa will be crucial for future quantitative studies, investigating the mechanism of cell penetration and in vivo biodistribution.

  2. Studies on the mode of action of calciferol. XIII. Development of a radioimmunoassay for vitamin D-dependent chick intestinal calcium-binding protein and tissue distribution

    International Nuclear Information System (INIS)

    A RIA for chick intestinal calcium-binding protein (CaBP) has been developed with a sensitivity of 1 ng. The antiserum was generated in rabbits injected with highly purified vitamin D-dependent chick intestinal CaBP. The assay employs the double antibody technique, and 125I-labeled CaBP was prepared using chloramine T. Low molecular weight peptide hormones and normal rabbit, rat, and human serum proteins show no cross-reactivity in the assay. Measurements of chick intestinal and kidney CaBP by RIA showed a good correlation with measurements of CaBP by the radial immunodiffusion method. The assay is reproducible (interassay variability, 16.3%) and precise (intraassay variability, 4.0%). The concentration of immunoreactive CaBP (iCaBP) in chick serum (2.7 ng/ml serum) can now be measured as early as 8 h after the administration of 6.5 nmol 1,25-dihydroxyvitamin D3; a maximum of 11 ng/ml is reached at 20 h. The level of CaBP in chick serum was found to be dependent on the dose of vitamin D3 or 1,25-dihydroxyvitamin D3 administered to the animal

  3. Studies on the mode of action of calciferol. XIII. Development of a radioimmunoassay for vitamin D-dependent chick intestinal calcium-binding protein and tissue distribution

    Energy Technology Data Exchange (ETDEWEB)

    Christakos, S.; Friedlander, E.J.; Frandsen, B.R.; Norman, A.W.

    1979-05-01

    A RIA for chick intestinal calcium-binding protein (CaBP) has been developed with a sensitivity of 1 ng. The antiserum was generated in rabbits injected with highly purified vitamin D-dependent chick intestinal CaBP. The assay employs the double antibody technique, and /sup 125/I-labeled CaBP was prepared using chloramine T. Low molecular weight peptide hormones and normal rabbit, rat, and human serum proteins show no cross-reactivity in the assay. Measurements of chick intestinal and kidney CaBP by RIA showed a good correlation with measurements of CaBP by the radial immunodiffusion method. The assay is reproducible (interassay variability, 16.3%) and precise (intraassay variability, 4.0%). The concentration of immunoreactive CaBP (iCaBP) in chick serum (2.7 ng/ml serum) can now be measured as early as 8 h after the administration of 6.5 nmol 1,25-dihydroxyvitamin D/sub 3/; a maximum of 11 ng/ml is reached at 20 h. The level of CaBP in chick serum was found to be dependent on the dose of vitamin D/sub 3/ or 1,25-dihydroxyvitamin D/sub 3/ administered to the animal.

  4. Receiving of iodoinsulin with preserved biological activity

    International Nuclear Information System (INIS)

    The paper presents a method of receiving iodoinsulin with preserved biological activity. As a raw material recrystallized bovine insulin produced by ''Polfa'' was used. Chloramine T was used as an oxidizing agent in the iodize reaction. Insulin was marked with 125I or 127I in the rate of molar concentration of NaI and insulin 0.6. The obtained product contained about 0.3 of iodine atom per one insulin molecule. Specific radioactivity of the iodoinsulin was between 77 and 147 μCi/μg. Such an insulin was in over 95% precipitable with trichloroacetic acid. Its immunological reactivity varied from 89% to 100% while biological activity, determined with the consumption of glucose by the fatty tissue of epididymis of rat, was 92% +- 24% of the native insulin activity. Half-life time of 125I insulin in the rat blood circulation was determined. Curve of the isotope disappearance was biphasic. Half-life time of the first phase (shorter one) was 0.64 +- 0.2 minute while the longer phase 8.89 +- 2.16 minutes. (author)

  5. The study of labeling with Iodine-131 of monoclonal antibody anti-CD20 used for the treatment of non-Hodgkin lymphoma; Estudo de marcacao com Iodo-131 de anticorpo monoclonal anti-CD20 na terapia de linfoma nao-Hodgkin

    Energy Technology Data Exchange (ETDEWEB)

    Akanji, Akinkunmi Ganiyu

    2006-07-01

    Lymphomas are malignancies of the lymphatic system, described by Thomas Hodgkin in 1932. Traditionally, lymphomas are classified in two basic groups: Hodgkin disease and non-Hodgkin lymphoma (NHL). Patients with NHL were earlier treated with radiotherapy alone or in combination with immunotherapy using monoclonal antibody anti-CD20 (ex., Rituximab-Mabthera, Roche). However, Radioimmunotherapy is a new modality of treatment for patients with NHL, in which cytotoxic radiation from therapeutic radioisotopes is delivered to tumors through monoclonal antibodies. This study focused on labeling conditions of monoclonal antibody anti-CD20 (Rituximab-Mabthera, Roche) with iodine-131, by direct radioiodination method using Chloramine-T as oxidizing agent. Labeling parameters investigated were: Radiochemical purity (RP), method of purification, incubation time, antibody mass, oxidative agent mass, stability in vitro, stability in vivo, immunoreactivity and biological distribution performed in normal Swiss mouse. Product of high radiochemical purity was obtained with no notable difference between the methods applied. No clear evidence of direct influence of incubation time on radiochemical purity of the labeled antibody was observed. Whereas, a clear evidence of direct influence of activity on radiochemical purity of the labeled antibody was observed when antibody mass was varied. After purification, the labeled product presented radiochemical purity of approximately 100 %. Product of superior radiochemical yield was observed when standard condition of labeling was used. The labeled product presented variation in radiochemical purity using five different stabilizer conditions. The condition in which gentisic acid was combined with freeze appears more suitable and capable of minimizing autoradiolysis of the antibody labeled with high therapeutic activity of iodine-131. The labeled product presented low immunoreactivity when compared to the literature. Biological distribution in

  6. The study of labeling with iodine-131 of monoclonal antibody anti-CD20 used for the treatment of non-Hodgkin lymphoma

    International Nuclear Information System (INIS)

    Lymphomas are malignancies of the lymphatic system, described by Thomas Hodgkin in 1932. Traditionally, lymphomas are classified in two basic groups: Hodgkin disease and non-Hodgkin lymphoma (NHL). Patients with NHL were earlier treated with radiotherapy alone or in combination with immunotherapy using monoclonal antibody anti-CD20 (ex., Rituximab-Mabthera, Roche). However, Radioimmunotherapy is a new modality of treatment for patients with NHL, in which cytotoxic radiation from therapeutic radioisotopes is delivered to tumors through monoclonal antibodies. This study focused on labeling conditions of monoclonal anti-CD20 (ex., Rituximab-Mabthera, Roche) with iodine-131, by direct radioiodination method using Chloramine-T as oxidizing agent. Labeling parameters investigated were: Radiochemical purity (RP), method of purification, incubation time, antibody mass, oxidative agent mass, stability in vitro, immunoreactivity and biological distribution performed in normal Swiss mouse. Product of high radiochemical purity was obtained with no notable difference between the methods applied. No clear evidence of direct influence of incubation time on radiochemical purity of the labeled antibody was observed. Whereas, a clear evidence of direct influence of activity on radiochemical purity of the labeled antibody was varied. After purification the labeled product presented radiochemical purity of approximately 100 %. Product of superior radiochemical yield was observed when standard condition of labeling was used. The labeled product presented variation in radiochemical purity using five different stabilizer conditions. The condition in which gentisic acid combined with freeze appears more suitable and capable of minimizing autoradiolysis of the antibody labeled with freeze appears more suitable and capable of minimizing autoradiolysis of the antibody labeled with high therapeutic activity of iodine-131. The labeled product presented low immunoreactivity when compared to the

  7. The study of labeling with Iodine-131 of monoclonal antibody anti-CD20 used for the treatment of non-Hodgkin lymphoma

    International Nuclear Information System (INIS)

    Lymphomas are malignancies of the lymphatic system, described by Thomas Hodgkin in 1932. Traditionally, lymphomas are classified in two basic groups: Hodgkin disease and non-Hodgkin lymphoma (NHL). Patients with NHL were earlier treated with radiotherapy alone or in combination with immunotherapy using monoclonal antibody anti-CD20 (ex., Rituximab-Mabthera, Roche). However, Radioimmunotherapy is a new modality of treatment for patients with NHL, in which cytotoxic radiation from therapeutic radioisotopes is delivered to tumors through monoclonal antibodies. This study focused on labeling conditions of monoclonal antibody anti-CD20 (Rituximab-Mabthera, Roche) with iodine-131, by direct radioiodination method using Chloramine-T as oxidizing agent. Labeling parameters investigated were: Radiochemical purity (RP), method of purification, incubation time, antibody mass, oxidative agent mass, stability in vitro, stability in vivo, immunoreactivity and biological distribution performed in normal Swiss mouse. Product of high radiochemical purity was obtained with no notable difference between the methods applied. No clear evidence of direct influence of incubation time on radiochemical purity of the labeled antibody was observed. Whereas, a clear evidence of direct influence of activity on radiochemical purity of the labeled antibody was observed when antibody mass was varied. After purification, the labeled product presented radiochemical purity of approximately 100 %. Product of superior radiochemical yield was observed when standard condition of labeling was used. The labeled product presented variation in radiochemical purity using five different stabilizer conditions. The condition in which gentisic acid was combined with freeze appears more suitable and capable of minimizing autoradiolysis of the antibody labeled with high therapeutic activity of iodine-131. The labeled product presented low immunoreactivity when compared to the literature. Biological distribution in

  8. Choice of labeling and cell line influences interactions between the Fab fragment AbD15179 and its target antigen CD44v6

    International Nuclear Information System (INIS)

    Medical imaging by use of immunotargeting generally relies on a labeled molecule binding to a specific target on the cell surface. It is important to utilize both cell-based and time-resolved binding assays in order to understand the properties of such molecular interactions in a relevant setting. In this report we describe the detailed characterization of the interaction properties for AbD15179, a promising CD44v6-targeting antibody fragment for radio-immunotargeting. Influence of labeling and cell-line model on the protein interaction kinetics was assessed using three different labeling approaches (111In, 125I and FITC) on three different squamous carcinoma cell lines. Interactions were measured using time-resolved assays on living cells, and further analyzed with Interaction Map®. Results demonstrated a general biphasic appearance of a high- and a low-affinity binding event in all cases. The relative contribution from these two interactions differed between conjugates. For 125I-Fab, the population of low-affinity binders could be significantly increased by extending the chloramine T exposure during labeling, whereas the 111In-labeling predominantly resulted in a high-affinity interaction. Interactions were also shown to be cell line dependent, with e.g. SCC-25 cells generally mediating a faster dissociation of conjugates compared to the other cell lines. In conclusion, we report both cell line dependent and labeling associated variations in interaction kinetics for AbD15179 binding to CD44v6. This has implications for cell-based kinetic assays and applications based on labeled conjugates in general, as well as in a clinical setting, where each individual tumor may create different kinetic profiles for the same conjugate

  9. Two Fatal Intoxications with Cyanohydrins.

    Science.gov (United States)

    Zheng, Shuiqing; Yuan, Xiaoliang; Wang, Wei; Liang, Chen; Cao, Fangqi; Zhang, Runsheng

    2016-06-01

    Cyanohydrins, also be called cyanoalcohols, are important industrial precursors to carboxylic acids and some amino acids. Acetone cyanohydrin (ACH) and formaldehyde cyanohydrin (glycolonitrile, FCH), which are the typical examples of cyanohydrins, are classified as extremely hazardous substances. As the cyanohydrins can readily decompose, and it is hard to find cyanohydrins in gastric contents and heart blood, the determination study in biological samples can be divided into two parts: the first is the determination of HCN by using a Prussian blue reaction and the HS-GC-MSD after derivatization by chloramine-T. The second is the determination of acetone or formaldehyde. In this part, headspace gas chromatography with flame ionization detector (HS-GC-FID) and solid phase microextraction (SPME)-gas chromatography with mass spectrometric detectors (GC-MSD) had been used. In this report, we reported two fatal intoxication cases of ACH and FCH; one person was killed by his wife by poisoning his food and the other was suicide by poison. Two real cases of ACH and FCH in human blood and gastric contents have been analyzed by using the above-mentioned method. The Prussian blue reaction was positive in the two cases. The peaks of acetone with retention times of 0.998 min appear in specimens of the deceased are consistent with the retention times of pure acetone. The peaks of formaldehyde with a retention time of 1.658 min appear in heart blood of the deceased, and the retention time of formaldehyde of the liquid is 1.674 min, which are consistent with the retention times of pure formaldehyde (1.673 min). PMID:27026650

  10. Considerations in the radioiodination and chelation labeling of an antiplatelet monoclonal antibody

    International Nuclear Information System (INIS)

    Radiolabeling of antibodies in particular with iodine nuclides frequently alters their biological behavior and compromises the specificity of binding to the in vivo antigens. Sensitivity to labeling chemistry however, is quite variable for different antibodies. This study was carried out to investigate the various factors affecting the binding to platelets (P) of an anti-P monoclonal antibody, 7E3, following iodination with I-123, I-125, I-131 and chelation labeling with In-111 and Tc-99m. Parameters such as the nature and amount of oxidant, reaction times, substitution level, specific activity etc., were studied. Results showed that each factor in addition to affecting chemical labeling yields also affected the binding of labeled 7E3 to P in whole blood and their blood clearance and clot uptake. With increasing I/7E3 or DTPA/7E3 molar ratios, a progressive decrease in binding to P resulted. Chloramine T (5-10 μg/100 μg 7E3) was superior to other oxidizing agents but the reaction times had to be ≤2 min (labeling yields 70 +- 10%). 7E3 appeared unaffected by specific activities of up to 40 μCi/μg (I-131 and In-111) and 300 μCi/μg (I-123). Satisfactory In-111-, I-131-, or I-123-7E3-P preparations were obtained that show considerable promise for localizing in vivo thrombi. Results of this study and prior experience with other antibodies indicate that in order to achieve maximum efficacy in imaging or therapy applications, individual antibodies may require a careful optimization of labeling procedures with different radionuclides

  11. A study on the metabolic pathway of pregnancy specific beta1-glycoprotein (SP1), 2

    International Nuclear Information System (INIS)

    SP1 was purified from human placentae, and the metabolism of 125I labeled SP1 was studied in non-pregnant and pregnant mice of ICR strain. Purification of SP1 was carried out by the method of Bohn (1971) and Nose (1981) with modifications. A preparation of purified SP1 was labeled with 125I by the Chloramine-T method. 125I-SP1 (0.1 ml of approximately 2.5 x 106 C.P.M./ml radioactivity) was injected into the subcutaneous tissue of both non-pregnant and pregnant mice. The animals were killed at 0.5, 1, 2, 4, 8 and 16 hours after the injection. The organs and tissues were collected, weighed and analysed for accumulated radioactivity. Non-pregnant mice tissue radioactivity exhibited the highest count in the kidney, followed by blood, ovary and uterus, spleen, liver, muscle and fat at 30 min. after the injection; similar tendencies were observed at other times. Radioactivity of the kidney was more than twice that of blood. A blood disappearance curve showed a half life of 8 hours. The radioactive substance was excreted in urine at a very high level from 30 min. to 4 hours, and in the faeces, it peaked at 8 hours. Pregnant mice tissue exhibited the highest count in the kidney, followed by blood, spleen, ovary and uterus, placenta, fat, muscle and fetus at 30 min. A blood disappearance curve showed a half life of about 11 hours. Radioactivity of the placenta exceeded that of blood after about 1.5 hour from the injection and reached a peak at 4 hours. It is suggested from this study that SP1 has an affinity to the placenta and its surroundings and is excreted to urine from blood quickly. (J.P.N.)

  12. Sorafenib-induced hepatocellular carcinoma cell death depends on reactive oxygen species production in vitro and in vivo.

    Science.gov (United States)

    Coriat, Romain; Nicco, Carole; Chéreau, Christiane; Mir, Olivier; Alexandre, Jérôme; Ropert, Stanislas; Weill, Bernard; Chaussade, Stanislas; Goldwasser, François; Batteux, Frédéric

    2012-10-01

    Sorafenib is presently the only effective therapy in advanced hepatocellular carcinoma (HCC). Because most anticancer drugs act, at least in part, through the generation of reactive oxygen species, we investigated whether sorafenib can induce an oxidative stress. The effects of sorafenib on intracellular ROS production and cell death were assessed in vitro in human (HepG2) and murine (Hepa 1.6) HCC cell lines and human endothelial cells (HUVEC) as controls. In addition, 26 sera from HCC patients treated by sorafenib were analyzed for serum levels of advanced oxidation protein products (AOPP). Sorafenib significantly and dose-dependently enhanced in vitro ROS production by HCC cells. The SOD mimic MnTBAP decreased sorafenib-induced lysis of HepG2 cells by 20% and of Hepa 1.6 cells by 75% compared with HCC cells treated with 5 mg/L sorafenib alone. MnTBAP significantly enhanced by 25% tumor growth in mice treated by sorafenib. On the other hand, serum levels of AOPP were higher in HCC patients treated by sorafenib than in sera collected before treatment (P < 0.001). An increase in serum AOPP concentration ≥0.2 μmol/L chloramine T equivalent after 15 days of treatment is a predictive factor for sorafenib response with higher progression free survival (P < 0.05) and overall survival rates (P < 0.05). As a conclusion, sorafenib dose-dependently induces the generation of ROS in tumor cells in vitro and in vivo. The sera of Sorafenib-treated HCC patients contain increased AOPP levels that are correlated with the clinical effectiveness of sorafenib and can be used as a marker of effectiveness of the drug. . PMID:22902857

  13. 99mTc labelled peptides for imaging of peripheral receptors

    International Nuclear Information System (INIS)

    The first trials of 99mTc labelling by direct method using dithionite as a reducing agent (prepared in the freeze-dried form) gave the yields of around 30%. RC-160 labelling with 125I by chloramine-T method resulted in 40-80% labelling yield. Our efforts were focused on BFC approach. HYNIC-TOC and HYNIC-RC-160 conjugates obtained in our laboratory were successfully labelled with 99mTc with the yields over 90%. HPLC and TLC methods were applied for quality control (QC) of the labelled preparation. Methods of in vitro (stability and protein binding) testing of the labelled preparations were adopted to our laboratory conditions. First attempts on dry kit formulation based on HYNIC-TOC conjugates with tricine, tricine/nicotinic acid and EDDA were described. Various amounts of tin (II) (as SnCl2) were added to the kits. Incubation conditions (time, temperature) were investigated. The kits were tested for labelling yield and radiochemical purity. It was shown that the results are at the same level or better than obtained in liquid phase but the procedure of labelling is significantly easier. Kit produced with tricine as co-ligand was labelled with 97% labelling yield after 30 min of incubation at room temperature, which is considered acceptable for diagnostic radiopharmaceutical preparation. Tricine/nicotinic acid kit requires heating to get labelling of around 95%. Similarly EDDA kit gives around 70% labelling after 30 min incubation at 80 deg. C. Further experiments on optimal kit composition and stability are required. Results of DOTA-RC-160 labelling with 90Y show that this isotope, manufactured by Radioisotope Centre POLATOM, can be successfully used for medical applications. (author)

  14. New bisphosphonate labeled with Iodine-131 for the palliative therapy for bone metastases pain

    International Nuclear Information System (INIS)

    The aim of this work was to obtain new bisphosphonate marked with 131I suitable for palliative treatment of bone metastases pain characteristics. Materials and Methods: It started with aromatic amino acids and the synthesis consisted of three stages: 1) Protection of amino groups by acetylation; 2) phosphonation protected amino acids with a mixture of phosphorous acid and phosphorus pentachloride; 3) Lack of protection of the amino groups by basic hydrolysis. The compounds obtained were characterized by IR, 1H NMR, RMN13-C mass. Los spectrometry bisphosphonic acids obtained were labeled with 131I using chloramine T and iodogen as oxidants. Stability of labeled compounds in aqueous solution was studied serum. 3 mg of 2-amino-3- (4-hydroxyphenyl) -1-hydroxypropyl-1,1-bisphosphonic acid labeled of 131I were administered to male wistar rats (170-190 g) through a lateral tail vein. The scintigraphic study was conducted at 2, 6 and 12 hours. Results: The yield of the reactions of the amino group protection four compounds ranged from 75 to 80%, while the phosphonation was between 50 and 60%. The radiochemical purity of 2-amino-3- (4-hydroxyphenyl) -1-hydroxypropyl-1,1- bisphosphonic acid labeled with 131I was (91.5 ± 1.4)% and its stability was satisfactory for 72h. Scintigraphic images suggest excretion by the kidneys of the compound and from 12 h post-administration begin to visualize bone structures of the animal, suggesting that the compound exhibits affinity for these tissues. Conclusions: A novel synthesis method with modifications that yielded the sodium salts of bisphosphonic acids starting from the respective aromatic amino acids was developed. 2-amino-3- (4-hydroxyphenyl) -1-hydroxypropyl-1,1-bisphosphonic acid 131I labeled was stable up to 72h and showed affinity for bone tissue. (author)

  15. Biochemical and pharmacological studies of native and irradiated crotamine with gamma radiation of Co60

    International Nuclear Information System (INIS)

    Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. This has been employed to attenuate animal toxins. Crotamine is a strongly basic polypeptide from South American rattlesnake venom, composed of 42 amino acid residues. It induces skeletal muscle spasms, leading to a spastic paralysis of hind limbs in mice. The objective was to carry out biochemical and pharmacological studies of native and irradiated crotamine with Co. Crotamine was purified from Crotalus durissus terrificus venom by Sephadex G-100 gel filtration followed by ion exchange chromatography, using a Fast performance Liquid Chromatography (FPLC) system. It was irradiated at 2 mg/ml in 0.15 m NaCl with 2.0 kGy gamma radiation emitted by a Co source. Native and irradiated crotamine were evaluated by biochemical characterization, toxic activity (LD50), and biodistribution. The native and irradiated crotamine were labeled with 29.6 MBq of I using chloramine T method and separated in a Sephadex G-50 column. Male Swiss mice (35 @ 5 g) were injected IP with 0.1 mL (2.4x10 cpm/mouse) of I native crotamine or with 0.4 mL (1.3 x 10 cpm/mouse) of I irradiated crotamine. The animals were sacrificed by ether inhalation at 0.08, 0.25, 0.5,1, 2, 3, 4, 8, 12, and 24 hours. Blood, spleen, liver, kidneys, brain, lungs, heart, and skeletal muscle were collected in order to determine radioactivity content. The results showed that gamma radiation did not change protein concentration, electrophoretic profile, or protein primary structure, although differences could be seen by spectroscopic techniques. Gamma radiation reduced crotamine toxicity, but did not eliminate bioactivity. Biodistribution studies showed that native and irradiated crotamine have hepatic metabolism and renal elimination. Native and irradiated crotamine have an affinity to skeletal muscle and did not cross the blood-brain barrier. (author)

  16. Biochemical and ultrastructural processing of [125I]epidermal growth factor in rat epidermis and hair follicles: accumulation of nuclear label

    International Nuclear Information System (INIS)

    Although the intracellular ultrastructural processing of epidermal growth factor (EGF) and its receptor have been described in cell culture systems, very few studies have examined this phenomenon in intact tissues. We have examined the ultrastructural and biochemical handling of [125I]EGF in the epidermis and hair follicle bulb of intact, viable, 3- to 5-day-old rat skin the EGF receptor distribution of which has already been documented and in which EGF has been shown to be biologically active. After incubation of explants with 10 nM [125I]EGF for 2.5 h at 25 degrees or 37 degrees C, radiolabel was detected over the basal cells of the epidermis and hair follicle outer root sheath, confirming previous light microscope observations. More specifically, silver grains were observed near coated and uncoated plasma membrane and coated membrane invaginations, Golgi apparatus, lysosomal structures, and nuclei. Sodium azide inhibited internalization of label, whereas a series of lysosomal inhibitors (chloroquine, monensin, and iodoacetamide) caused a slight increase in silver grains associated with lysosomal vesicles and a decrease in nuclear label. Biochemical analysis indicated that greater than 35% of radioactivity following incubation at 37 degrees C was in the form of degraded [125I]EGF fragments and that inclusion of chloroquine, monensin, and iodoacetamide reduced this value to 20.8%, 8.6%, and 4.0%, respectively. In addition, chloramine T-prepared [125I]EGF was found to be covalently cross-linked with low efficiency to a protein having the molecular weight of the EGF receptor. These data are discussed in the light of the effects of EGF on epithelial cell proliferation in skin

  17. Development of anti-CD30 radioimmunoconstructs (RICs) for treatment of Hodgkin's lymphoma. Studies with cell lines and animal studies

    International Nuclear Information System (INIS)

    Objectives: comparison of the binding affinity to a CD30-positive Hodgkin lymphoma (HL) cell line and biodistribution in HL bearing mice of new anti-CD30 radioimmunoconjugates (RICs) of varying structure and labelling nuclides. Methods: The antibodies Ki-4 and 5F11 were radioiodinated by the chloramine T method or labelled with 111In via p-NCS-Benzyl-DOTA. In addition, the Ki-4-dimer was investigated in the iodinated form. The RICs were analyzed for retained immunoreactivity by immunochromatography. In-vitro binding studies were performed on CD30-positive L540 cell lines. For in-vivo biodistribution studies, SCID mice bearing human HL xenografts were injected with the various radio-immunoconjugates. After 24 h, activities in the organs and tumour were measured for all 5 RICs. Tumour-free animals were studied in the same way with 131I-Ki-4 24 h p. i. The three RICs with the highest tumour/background ratios 24 h p.i. (131I-Ki-4, 131I-5F11, 111In-bz-DOTA-Ki-4) were analysed further at 48 h and 72 h. Results: all the RICs were successfully labelled with high specific activities (28-47 TBq/mmol) and sufficient radiochemical yields (> 80%). Scatchard plot analysis proved high tumour affinity (KD = 20-220 nmol/l). In-vivo tumour accumulation in % of injected dose per g tissue (% ID/g) lay between 2.6 (131I-5F11) and 12.3 % ID/g (131I-Ki-4) with permanently high background in blood. Tumour/blood-ratios of all RICs were below one at all time points. Conclusions: in-vitro tumour cell affinities of all RICs were promising. However, in-vivo biokinetics tested in the mouse model did not meet expectations. This highlights the importance of developing and testing further new anti-CD30 conjugates. (orig.)

  18. A radioimmunoassay detecting the borine leukaemia virus transmembrane protein gp30 and anti-gp30 antibodies in the serum of cattle

    International Nuclear Information System (INIS)

    From virus-infected fetal lamb kidney (FLK) cells a relatively homogeneous envelope transmembrane protein gp30 of bovine leukemia virus (BLV) was isolated. As shown by a partial sequence analysis of the N-terminus of this protein, the gp30 preparation contained only traces (less than 5%) of p24 gag protein: rabbit anti-gp30 serum did not cross react with the BLV proteins gp51, p12, p151, p152 and p10 but reacted weakly with the p24 polypeptide. 125I-labelled gp30 (chloramine-T) was precipitated with the serum of BLV-infected cattle. Nonlabelled preparation of gp30 competitively inhibited the reaction of 125I-labelled gp30 with natural antibodies. 193 cattle sera were investigated by liquid phase radioimmunoassay (RIA) using 125I-gp30, gp51 and p24 antigens. Sixteen noninfected cattle sera were negative in all tests. The 177 serum samples of BLV-infected animals were examined to the diagnostic value of the three tests. Of these, 175 were positive in gp51 RIA, 172 in p24 RIA and 164 in gp30 RIA. In all three tests, 159 sera were positive while 18 sera, mostly coming from animals with normal leukocyte counts, were positive only either with gp51 or p24, or were double positive with either gp51/p24 or gp51/gp30. It is concluded that gp51 RIA is superior to both gp30 and p24 RIA and that gp30 RIA will be useful for investigating the role of gp30 in virus pathogenicity. (author). 2 figs., 2 tabs., 33 refs

  19. Role of the metabolism of parathyroid hormone. [Rats

    Energy Technology Data Exchange (ETDEWEB)

    Teitelbaum, Anne P.

    1978-01-01

    The heterogeneity of parathyroid hormone (PTH) in plasma has prompted investigations of the metabolism of PTH and its relationship to hormone action. The time course of tissue distribution and metabolism of electrolytically iodinated PTH (E-PTH) previously shown to retain biological activity was compared with that of inactive PTH iodinated with Chloramine-T (CT-PTH). Labeled PTH (0.4 ..mu..g) was injected in the saphenous veins of anesthetized rats which were sacrificed at 1, 3, 5, 10, and 20 min. Tissue extracts from kidney, liver, and serum were chromatographed to separate intact PTH from its metabolites. In the kidney, the initial rate of degradation of E-PTH was greater than that of CT-PTH. The difference in initial rates of metabolism may be due, in part, to receptor-specific hydrolysis on peritubular cell membranes which selectively act on biologically active PTH molecules. PTH-responsive adenyl cyclase activity in isolated kidney cortex plasma membranes was measured and PTH metabolism was monitored simultaneously. When degradation was completely blocked by histone f/sub 3/ (1 mg/ml), adenyl cyclase activity was significantly increased over control. In addition, when adenyl cyclase activity was negligible, the rate of PTH degradation by the membranes was not significantly diminished. Consistent with the in vivo data was the observation that E-PTH is metabolized by these membranes at a greater rate than CT-PTH. The data demonstrate the existence of a receptor-specific metabolism at sites which are independent of PTH receptor mediated adenyl cyclase activity.

  20. Rhodamine-123: Radioiodination and evaluation as an agent for imaging and radiotherapy of certain tumors

    International Nuclear Information System (INIS)

    Rhodamine-123 (Rh-123) is a cationic lypophilic fluorescent dye which localizes in the mitochondria of living cells. The compound subsequently clears through normal cells but is selectively retained in carcinoma cells. As a result, the compound exhibits anticarcinoma activity both in vitro and in vivo. This high selectivity prompted us to evaluate Rhodamine-123 as an agent for imaging and radiotherapy. Accordingly in the present study Rh-123 was labeled with iodine-125 by chloramine-T. Tissue distributions were studied for C-3Hf/SED brown mice bearing 1 cm diameter implanted SCC VII carcinoma; CDF-1 mice with MB49 bladder carcinoma, nude mice with human CX-1 colon carcinoma and brown mice with murine mammary tumor. The results indicated that (i) initially the radioactivity was taken up by the liver (3.4%), thyroid (3.8%), kidney (2.3%) and tumor (0.8%); (ii) the radioactivity from all the normal tissues cleared within 24 hours but not from the tumors (iii) in tumors the radioactivity remained unchanged. This resulted in higher tumor/blood (1.2%) and tumor/muscle (4.2%) ratios which allows detection of the tumors by gamma camera imaging techniques. In the case of nude mice with human imaging CX-1 colon carcinoma and brown mice with murine mammary tumor the tumor/muscle ratios were interestingly much higher - 8.9% and 9.3%, respectively. These results clearly show that radioiodinated Rh-123 is a potential agent for imaging and radiotherapy of certain tumors

  1. The development of a human calcitonin radioimunoassay, with 'in house' reagent production, for application to the early diagnosis of medullary thyroid carcioma

    International Nuclear Information System (INIS)

    Reagent production for human Calcitonin (hCT) Radioimmunoassay (RIA) was carried out in our laboratory starting from a kind donation of human synthetic preparation from CIBA (Basel, Switzerland). This product was used for anti-hCT antibody production in rabbits and guinea-pigs and for radioiodination, according to two different methods: classical and stoichiometric Chloramine T techniques. The use of Sephadex G-50 in tracer purification allowed the obtainement of 125I-hCT free of high molecular weight contaminats. A repurification on polyacrylamide gel electrophoresis provided 125I-hCT of higher specific activity that presented specific binginds, to good quality antisera, of the same order of imported tracers (∼ 45%). Different antisera were obtained in rabbits and quinea-pigs, but only one (GP2-IPEN) could be used in such a dilution (1:4000) to provide highly sensitive curves (minimal detectable concentration < 70 pg/ml) presenting, however, very low specific bindings (7-10%). For this reason, in order to be able to set up a regular quality control of our hCT-RIA technique, an antiserum kindly donated by the Karolinska Institute (Stockholm, Sweden) was used. This way, through the use of an higher antibody dilution (1:8000), higher specific bindings (20-30%), higher sensitivies (< 30 pg/ml) and satisfactory precision were obtained. We consider this study a first approach to a complete national production of hCT-RIA reagents, that, at present moment, depends practically only from the obtainement of a high avidity anti-hCT antiserum. More has to be done on accuracy and correct clinical application of this assay to the screening of the familial form of Medullary Thyroid Carcinoma. We also emphasize the fact, due to our limited financial possibilities, all the work was carried out with great economy, taking advantage of previously set up techniques and of the experience already acquired in this field of work. (author)

  2. Synthesis and enantiomeric evaluation of radiolabelled methyl phenidate for the study of dopamine reuptake sites

    International Nuclear Information System (INIS)

    Full text: Neurological diseases such as Parkinson's Disease and associated Movement Disorders have been characterised by reductions in the number of dopamine re-uptake sites or dopamine transporters (DAT) on presynaptic neurons in the striatum. Radiolabelled drugs which display specific and selective binding to the DAT has thus found clinical utility in medical imaging. The psychomotor stimulant methyl phenidate (MP) or Ritalin 1 and several derivatives have demonstrated high affinity binding to these DAT where they exert their pharmacological action. MP possesses two chiral centers with its pharmacological activity being attributed to the dl-threo diastereomer, the dl-erythro being inactive. Furthermore, imaging studies using Positron Emission Tomography (PET) with carbon-11 radiolabelled MP confirmed the d-threo enantiomer to be most active. In vitro studies indicate that compounds substituted with either bromine or iodine in the 3 position of the aromatic ring exhibit high affinity and selective binding to DAT and were thus targeted for radiolabelling with both the PET tracer Bromine-76 as well as the SPECT tracer lodione-123. Threo methyl phenidate and its halogenated derivatives were prepared by the condensation of 3-bromophenylacetonitrile and 2-bromopyridine according to modified literature methods. Radiohalogenation with either 76Br or 123I was achieved by halodestannylation reactions of the corresponding tributyl stannane precursor in the presence of chloramine-T as the oxidant. Purification by C-18 reverse phase HPLC gave the dl-threo product in 70-80% radiochemical yield and in greater than 95% radiochemical purity. Separation of the d and / enantiomers was achieved by chiral HPLC. Biodistribution studies in rodents indicated high uptake of radioactivity in tissues with known DAT sites. PET and SPECT imaging studies in primates indicated high uptake in the striatum compared to the cerebellum reference tissue. The synthesis, diastereomeric separation

  3. Role of the metabolism of parathyroid hormone

    International Nuclear Information System (INIS)

    The heterogeneity of parathyroid hormone (PTH) in plasma has prompted investigations of the metabolism of PTH and its relationship to hormone action. The time course of tissue distribution and metabolism of electrolytically iodinated PTH (E-PTH) previously shown to retain biological activity was compared with that of inactive PTH iodinated with Chloramine-T (CT-PTH). Labeled PTH (0.4 μg) was injected in the saphenous veins of anesthetized rats which were sacrificed at 1, 3, 5, 10, and 20 min. Tissue extracts from kidney, liver, and serum were chromatographed to separate intact PTH from its metabolites. In the kidney, the initial rate of degradation of E-PTH was greater than that of CT-PTH. The difference in initial rates of metabolism may be due, in part, to receptor-specific hydrolysis on peritubular cell membranes which selectively act on biologically active PTH molecules. PTH-responsive adenyl cyclase activity in isolated kidney cortex plasma membranes was measured and PTH metabolism was monitored simultaneously. When degradation was completely blocked by histone f3 (1 mg/ml), adenyl cyclase activity was significantly increased over control. In addition, when adenyl cyclase activity was negligible, the rate of PTH degradation by the membranes was not significantly diminished. Consistent with the in vivo data was the observation that E-PTH is metabolized by these membranes at a greater rate than CT-PTH. The data demonstrate the existence of a receptor-specific metabolism at sites which are independent of PTH receptor mediated adenyl cyclase activity

  4. Subunit structure of the follitropin receptor

    International Nuclear Information System (INIS)

    Both of the α and β subunits of intact human follitropin (FSH) were radioiodinated with 125I-FSH-sodium iodide and chloramine-T, and could be resolved on polyacrylamide gels (SDS-PAGE). The electrophoretic mobility of radioiodinated FSH α and β subunits as well as the αβ dimer changed markedly depending on the concentration of reducing agents. 125I-FSH (Ka = 1.4 x 1010 M-1), complexes to the receptor on procine granulosa cells or in Triton X-100 extracts, was affinity-crosslinked with a cleavable (nondisulfide) homobifunctional reagent, bis[2-(succinimidooxycarbonyloxy)ethyl]sulfone, solubilized in sodium dodecyl sulfate with or without reducing agents, and electrophoresed. Crosslinked samples revealed three additional bands of slower electrophoretic mobility, corresponding to 65 (unreduced 62), 83 (unreduced 76) and 117 (unreduced 110)kDa, in addition to hormone bands. Formation of the three bands requires the 125I-FSH hormone to bind specifically to the receptor with subsequent cross-linking. The rate of formation and cleavage of the cross-linked complexes indicated a sequential and incremental addition of 22, 18, and 34 kDa components to the FSH αβ dimer. The results of reduction of cross-linked complexes demonstrated the existence of disulfide linkage between the three components. FSH was photoactively derivatized with N-hydroxysuccinimide ester of 4-azidobenzolyl-glycine and radioiodinated for photoaffinity labeling. When derivatized 125I-FSH (Ka = 1.12 1010 M-1) bound to the cell was photolyzed for cross-linking and resolved on the SDS-PAGE, two new bands (106 and 61 kDa) under reducing condition appeared in addition to the hormone bands. Upon reduction with dithiotheitol and second-dimensional electrophoresis, the unreduced 104 kDa (reduced 106 kDa) band released two small components 31 and 14 kDa

  5. 原料奶粉及乳饮料中L-羟脯氨酸的含量测定%Determination of L-hydroxyproline in raw milk powder and milk drink

    Institute of Scientific and Technical Information of China (English)

    陈铭中; 钟旭美; 胡洪森

    2011-01-01

    The method of P-dimethylaminobenzaldehyde spectrophotom etry was used to determine L-hydroxyproline in raw milk powder and milk drink.The result was stable and the recovery rate was high.After hydrolyzed with acid,L-hydroxyproline was released and oxidized by chloramine T.L-hydroxyproline oxide reacted with P-dimethylaminobenzaldehyde and formed red compounds,the absorbance was detected at 580 nm.The method was simple and accurate.Compared with other detecting methods,the expense of it was smaller.It could provide reference for enterprises to detect whether product was adulterated hydrolyzed protein in raw milk powder and milk drink.%采用对二甲氨基苯甲醛分光光度法测定奶粉及乳饮料中L-羟脯氨酸,具有较好的稳定性。奶粉及乳饮料经浓盐酸水解,得到的L-羟脯氨酸经过氯胺T氧化,与对二甲氨基苯甲醛反应生成红色物质,在558nm下测定吸光值。该方法操作简单、准确率高、检测费用相对少,可用于企业奶粉原料掺水解蛋白及产品中是否掺有水解蛋白的检测提供依据。

  6. Identification of the binding subunit of the D/sub 1/-dopamine receptor by photoaffinity crosslinking

    Energy Technology Data Exchange (ETDEWEB)

    Amlaiky, N.; Berger, J.G.; Chang, W.; McQuade, R.D.; Caron, M.G.

    1986-03-01

    A derivative of the potent D/sub 1/ antagonist SCH-23390 has been synthesized. This compound, (R,S)-1-(m-aminophenyl)-7-chloro-8-hydroxy-3-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine (SCH-38548), has been radioiodinated by a chloramine T procedure yielding 3 radioiodinated products. One of these separated isomers (R/sub f/ = 0.35; CH/sub 2/Cl/sub 2/:MEOH:TEA; 82.5:17.5:0.1 on TLC) binds reversibly to rat striatal membranes with high affinity (K/sub D/ approx. 80 pM) appropriate stereoselectivity and D/sub 1/-dopaminergic specificity. (/sup 125/I)SCH-38548 can be covalently incorporated into a peptide of M/sub r/ approx. 72,000 using the heterobifunctional crosslinking reagent N-succinimidyl-6-(4'-azido-2'-nitro-phenylamino) hexanoate. Covalent incorporation of (/sup 125/I) SCH-38548 into the M/sub r/ approx. 72,000 peptide can be blocked by dopaminergic agents with D/sub 1/-dopaminergic specificity (for agonists: SKF 38393 > apomorphine > dopamine; for antagonists: SCH-23390 > cis-flupentixol >>> trans-flupentixol). The D/sub 1/-dopaminergic selectivity and specificity of the labeling was further demonstrated by the fact that other antagonists such as domperidone, ketanserin, phentolamine and alprenolol did not compete for the covalent labeling of the M/sub r/ approx. 72,000 peptide. This new radioligand should be useful in the molecular characterization of the D/sub 1/-dopaminergic receptor from various sources.

  7. Pharmacokinetics of Pegylated recombinant new human Interleukin-6 (PET-rhIL-6)

    International Nuclear Information System (INIS)

    In this study, the newly developed Pegylated recombinant human Interleukin-6 (PEG-rhIL-6) was investigated. With 125I labeled PEG-rhIL-6 by two-phase chloramine-T method. Thirty of the SD rats were randomly divided into 6 groups (group 1, 2, 3, 4, 5 and 6, respectively), with 5 animals (3 males and 2 females) each group. Group 1, 2 and 3 were injected subcutaneously with 125I-PEG-rhIL-6 at the dose of 40, 20 and 3 μg/kg, respectively. Group 4, 5 and 6 were injected intravenously with 125I-PEG-rhIL-6 with the same dose level, respectively. Blood samples were collected at different time intervals after injection. The plasma concentration (ng/ml) of 125I-PEG-rhIL-6 were determined by 125I isotope tracing method and then assessed with 3P87 software to obtain the pharmacokinetic parameters. Results clearly showed that 1/2 ke (20.41, 21.53, 19.77) and tl/2 ka (10.44, 11.26, 11.37) of group 1-3 are higher number than t1/2β (17.54, 18.78, 17.81) and t1/2α (1.93, 1.60, 1.78) of group 4-6. The pharmacological activity of 125I-PEG-rhIL-6 maintain longer time by subcutaneous injection; The pharmacokinetic of V/Fc after sc (694.96 ml/kg) is higher than those after iv (115.26 ml/kg), which showed that the excretion speed of 125-PEG-rhIL-6 given by sc was slowly. The above results obtained indicated that the pharmacokinetic characteristics of 125I-PEG-rhIL-6 would provide important information for clinical application and the subcutaneous injection is better. (authors)

  8. SPECT of Transplanted Islets of Langerhans by Dopamine 2 Receptor Targeting in a Rat Model.

    Science.gov (United States)

    Willekens, Stefanie M A; van der Kroon, Inge; Joosten, Lieke; Frielink, Cathelijne; Boerman, Otto C; van den Broek, Sebastiaan A M W; Brom, Maarten; Gotthardt, Martin

    2016-01-01

    Pancreatic islet transplantation can be a more permanent treatment for type 1 diabetes compared to daily insulin administration. Quantitative and longitudinal noninvasive imaging of viable transplanted islets might help to further improve this novel therapy. Since islets express dopamine 2 (D2) receptors, they could be visualized by targeting this receptor. Therefore, the D2 receptor antagonist based tracer [(125/123)I][IBZM] was selected to visualize transplanted islets in a rat model. BZM was radioiodinated, and the labeling was optimized for position 3 of the aromatic ring. [(125)I]-3-IBZM was characterized in vitro using INS-1 cells and isolated islets. Subsequently, 1,000 islets were transplanted in the calf muscle of WAG/Rij rats and SPECT/CT images were acquired 6 weeks after transplantation. Finally, the graft containing muscle was dissected and analyzed immunohistochemically. Oxidative radioiodination resulted in 3 IBZM isomers with different receptor affinities. The use of 0.6 mg/mL chloramine-T hydrate resulted in high yield formation of predominantly [(125)I]-3-IBZM, the isomer harboring the highest receptor affinity. The tracer showed D2 receptor mediated binding to isolated islets in vitro. The transplant could be visualized by SPECT 6 weeks after transplantation. The transplants could be localized in the calf muscle and showed insulin and glucagon expression, indicating targeting of viable and functional islets in the transplant. Radioiodination was optimized to produce high yields of [(125)I]-3-IBZM, the isomer showing optimal D2R binding. Furthermore, [(123)I]IBZM specifically targets the D2 receptors on transplanted islets. In conclusion, this tracer shows potential for noninvasive in vivo detection of islets grafted in the muscle by D2 receptor targeting. PMID:26607139

  9. Development of simple immunoradiometric assays using avidin coupled to polystyrene beads as a common solid phase

    International Nuclear Information System (INIS)

    In this paper, we describe the preparation and application of avidin coupled polystyrene beads as a common solid phase for use in immunoradiometric assays (IRMAs). The assay system is based on two matched commercial monoclonal antibodies, of which, the capture antibody is biotinylated using biotinamidocaproate N-hydroxysuccinimide ester and the detection antibody is radiolabeled with 125I by conventional Chloramine-T method. Avidin was immobilized on the polystyrene beads through a primary coat of bovine serum albumin using glutaraldhyde activation method. Various factors, such as concentration of reagents, incubation time, etc. were optimised to obtain a simple assay protocol consisting of only two pipetting steps, namely, that of a mixture of the two labelled antibodies (radiolabelled and biotinylated) and of the standard or sample. The advantage of the Avidin-Biotin system is the improved sensitivity, economy of antibody and the possibility to use a common solid phase in assays for different analytes. Using the polystyrene beads along with the novel decanting device, it has been possible to achieve the convenience of the 'coated-tube' technology without the expensive automation necessary for large scale preparation of antibody coated tubes. This protocol has been successfully applied to Prolactin, LH and FSH assays. The sensitivity of the Prolactin assay is 8μIU/mL (0.3 ng/mL), that of the FSH assay is 1mIU/mL and that of the LH assay is 0.9 mIU/mL. The intra-assay and inter-assay variations were <10%. Shelf life of the avidin coupled beads was found to be about 8 months and that of the biotin labelled antibodies up to 18 months. (author)

  10. Radioimmunoassay of drugs: Phenytoin, clonidine and theophylline

    International Nuclear Information System (INIS)

    The development of radioimmunoassay procedures using 125I labelled tracers, for the drugs phenytoin, clonidine and theophylline is described. These drugs are conjugated to tyrosine methyl ester (TME) and bovine serum albumin (BSA) after suitable chemical modification, for preparation of radioiodinated drugs and antisera respectively. Phenytoin was modified to phenytoin valeric acid (P-VA) and phenytoin acetic acid (p-AA). In the case of clonidine, 4 carboxy clonidine (4-CLD) was used as the starting material, while for theophylline, 7-propionic acid (7-PAT) and 8-butyric acid (8-BAT) derivatives were made. Phenytoin and clonidine derivatives were coupled to BSA by the carbodiimide method. Theophylline derivatives were coupled to BSA by the mixed anhydride method. The drug-BSA conjugates were purified by dialysis and emulsified in complete Freund's adjuvant for immunization in rabbits. The different drug derivatives were coupled to TME using carbodiimide. The conjugates were purified by thin layer chromatography (TLC). Iodine-125 labelled tracers were prepared from the drug-TME derivatives using the chloramine-T method and purified by TLC or gel filtration. In phenytoin and theophylline good separation was obtained with TLC, while in clonidine, gel filtration was found to be better. Dextran coated charcoal was used as the separation system for clonidine, while polyethylene glycol was used for phenytoin and theophylline. Various factors such as time, temperature, concentration of reagents, serum interference and separation system were optimized to arrive at a suitable assay system for each of the drugs. The optimized assay systems were validated by precision profiles, interassay and intra-assay variations and specificity studies. These optimized systems have adequate sensitivity and can be used for the measurement of the drugs in serum without prior extraction of the samples. (author). 18 refs, 3 figs, 4 tabs

  11. RADIOCHEMICAL STUDIES ON ALPHA FETOPROTEIN RADIOIMMUNOASSAY SOLID PHASE COATED BEADS

    International Nuclear Information System (INIS)

    Alpha fetoprotein (AFP) is a marker for hepatocellular and germ cell carcinoma. There are many different techniques used for measuring AFP in blood where the most accurate one is the immunoassay technique. The aim of the present study was to evaluate, optimize and prepare anti-AFP solid phase coated beads and use it for the determination of AFP in serum. The anti-AFP polyclonal antibodies were prepared by immunization of five rats with a highly purified AFP antigen and the anti-sera obtained were used for coating polystyrene beads to obtain the solid phase coated beads. Also, the AFP antigen was labelled with 125 I using chloramin-T (Ch-T) as oxidizing agent and the tracer obtained was purified using sephadex G-25 (PD-10) chromatography. The assay was performed using a set of AFP standards prepared by diluting the cord blood. The suitable conditions for coating process were obtained which include pH 8, molarity of coating buffer 0.05 M, volume of coating buffer 100 ml and dilution of antibody 1:1000 for coating 1000 beads. Because the coated beads prepared using borate buffer is more suitable than prepared using carbonate or phosphate buffers, they were chosen to complete the optimization and validation study. The optimization and characterization of the assay were performed to evaluate the quality of the proposed system. The system prepared proved a low cost, simple, sensitive and accurate results. The prepared system can be used to evaluate AFP in the blood and this will be helpful in diagnosing some diseases such as hepatocellular carcinoma and neural tube defects

  12. Radioimmunoassay kit formulation and its validation for serum progesterone using progesterone radiotracer purified by gel filtration

    International Nuclear Information System (INIS)

    Purification of the radioiodinated progesterone tyrosine methyl ester conjugate by gel filtration and the development, optimization and clinical validation of a direct radioimmunoassay (RIA) of progesterone using this radiotracer are described. High purity radiotracer is essential for the error free performance of any RIA. Progesterone 11α hemisuccinate was conjugated to tyrosine methyl ester (TME) by the mixed anhydride method and this conjugate was then radioiodinated by the chloramine-T method. Purification of the radioiodinated product was carried out by gel filtration. About 12 batches of the radiotracer were prepared and purified. The purification by gel filtration gave reproducible elution pattern and purity. The radiotracer thus purified was found to have consistent quality as compared to that of any other purification methods. Non-specific binding of the radiotracer was found to be 95% as checked by paper electrophoresis. The stability (retention of the immunoreactivity) of the radiotracer was two to three months. No appreciable changes in the assay characteristics were observed during this period. The assay involved 3 hours incubation of progesterone antibody with individual standards or sample and radiotracer at room temperature. The optimized assay was then validated for internal and external quality control parameters. A RIA kit was then formulated with this radiotracer for estimation of progesterone in serum. The assay kit consisted of lyophilized individual standards ranging from 0.25 to 50 ng/ml. The clinical performance of the developed kit was compared with that of a commercial ELISA kit and a correlation of 0.94 was observed. (author)

  13. Fast determination of cyanide by paper disk method%氰化物纸片快速测定食品中的氰化物

    Institute of Scientific and Technical Information of China (English)

    杨俊; 陈亿展; 孟令兵; 赖小丽; 李意

    2012-01-01

    目的:建立食品中氰化物的纸片速测法并应用于重大活动保障中.方法:食品中的氰化物经水浸取后,与氯胺T反应生成氯化氰,继而与异烟酸反应,并经水解而成戊烯二醛,最后与1,3-二甲基巴比妥酸作用生成紫蓝色化合物,比色定量.结果:方法检出限为1.00 mg/kg,准确度和精密度都较为理想.结论:氰化物纸片速测法具有灵敏度高,快速,携带方便的特点,适合于重大活动保障中氰化物的快速测定.%Objective:To establish a method for fast determination of cyanide in food by paper disk method in important Activities. Methods: Cyanide in food was leached with water,and then reacted with chloramine T to form ey-anochloride which reacted with isonicotinic acid, the product was hydrolyed to glutaconaldehyde, and finally it reacted with 1,3- dimethyl barbituric acid to form a violet blue compound. The content of cyanide was quantitated colorime-trically. Results: The detection limit of the method was 1. 00 mg/kg, the recoveries and the precision were satisfactory. Conclusion: The method was sensitive, fast and convenient. It is suitable to determine cyanide in food in important Activities.

  14. Preparation of mono-radioiodinated tracers for study of the in vivo metabolism of atrial natriuretic peptide in humans

    International Nuclear Information System (INIS)

    The authors evaluate the optimum chemical conditions for labelling atrial natriuretic peptide (ANP) and its metabolites and for preparing highly purified radiotracers which can be used for in vivo kinetic studies of ANP in humans. Synthetic α h1-28ANP and some hormone metabolites were iodinated with Na125I or Na131I by means of the lactoperoxidase (ANP) or the chloramine-T (ANP metabolites) technique. The biological activity of labelled ANP was tested by means of a binding study using mouse cardiac membranes. A high-performance liquid chromatography (HPLC) procedure was used to purify the labelled hormone and the principal labelled metabolites in venous plasma samples collected up to 50 min after the injection of 125I-labelled ANP from nine healthy men. The main ANP kinetic parameters were derived from the disappearance curves of the [125I]ANP, which were satisfactorily fitted by a bi-exponential function in all subjects. The main advantages of this tracer technique are high accuracy, allowing the identification of the metabolites produced in vivo under steady-state conditions after injection of the precursor (labelled hormone) high sensitivity, allowing the detection of minimal quantities of metabolites high specificity, allowing the detection of possible in vitro artefactual generation of cleavage products of ANP using an internal labelled standard. Utilizing this tracer method, it was possible to estimate the principal parameters of ANP kinetics and also to plot the appearance curves of the labelled metabolites produced in vivo after the injection of the labelled precursor. (orig.). With 5 figs

  15. Problems in the application of labelled antibody techniques to communicable and parasitic diseases

    International Nuclear Information System (INIS)

    Two-site immunoradiometric and universal reagent techniques, using radiolabelled antibody, may be applied to communicable diseases. Labelled antibody techniques avoid the problems of purifying and then atraumatically radioiodinating the microorganismal antigens for radioimmunoassay. The application of solid-phase radiolabelled techniques to detect antigenaemia and circulating antibodies in mycobacterial diseases and amoebiasis caused by Mycobacterium tuberculosis and Entamoeba histolytica is described. Methods of antibody radioiodination (Chloramine-T, lactoperoxidase and iodogen) are compared, as well as the relative efficacy of labelling immunoglobulin sodium sulphate precipitate fractions vis-a-vis antibodies purified by affinity chromatography on antigen linked to immunoadsorbents (CNBr Sepharose 4B, diazocellulose). The problems of non-specific reactions because of interglobulin reactions or sticky IgM antibodies adhering to plastic solid phases are emphasized. Serious problems may arise if the antisera employed for labelling have themselves been raised against immunogens with complete Freund' s adjuvant because of anti-mycobacterial antibodies. A non-specific reaction in a communicable disease/infestation may represent a low level of exposure and a low level specific reaction, and the problem of obtaining non-infected non-exposed controls arises. Even neonatal blood may contain material IgG antibodies. Various methods of minimizing non-specific interglobulin reactions are stressed to obtain optimal sensitivity, as well as the need for 'matching' the specific antiserum and the universal reagent. Reference is made to the use of monoclonal antibodies derived from in vitro hybridomas in overcoming some of the problems at present limiting the labelled antibody techniques

  16. Prolactin-binding components in rabbit mammary gland: characterization by partial purification and affinity labeling

    International Nuclear Information System (INIS)

    The molecular characteristics of the PRL receptor isolated from rabbit mammary gland microsomes were investigated. Two approaches were employed: 1) affinity purification of PRL receptors and direct electrophoretic analysis, and 2) affinity cross-linking of microsomal receptors with [125I]ovine PRL [(125I]oPRL). PRL receptors were solubilized from mammary microsomes with 3-[(3-cholamidopropyl)dimethylammonio]1-propane sulfonate and purified using an oPRL agarose affinity column. Sodium dodecylsulfate-polyacrylamide gel electrophoresis and silver staining of the gel revealed at least nine bands, including a 32,000 mol wt band which was most intensively labeled with 125I using the chloramine-T method. Covalent labeling of PRL receptors with [125I]oPRL was performed using N-hydroxysuccinimidyl-4-azido benzoate, disuccinimidyl suberate, or ethylene glycol bis (succinimidyl succinate). A single band of 59,000 mol wt was produced by all three cross-linkers when sodium dodecylsulfate-polyacrylamide gel electrophoresis was performed under reducing conditions. Assuming 1:1 binding of hormone and binding subunit and by subtracting the mol wt of [125I]oPRL, which was estimated from the migration distance on the gel, the mol wt of the binding subunit was calculated as 32,000. In the absence of dithiothreitol during electrophoresis, only one major hormone-receptor complex band was observed. The same mol wt binding components were also detected in microsomal fractions of rabbit kidney, ovary, and adrenal. A slightly higher mol wt binding subunit was observed in rat liver microsomes. Rabbit liver microsomes revealed five [125I]oPRL-binding components, three of which were considered to be those of a GH receptor. Moreover, affinity labeling of detergent-solubilized and affinity purified mammary PRL receptors showed a similar major binding subunit

  17. Eradication of colon cancer cells before tumour formation in the peritoneal cavity of mice treated with intraperitoneal Re-186 radioimmunotherapy

    International Nuclear Information System (INIS)

    A treatment adjuvant to surgical resection of the primary lesion has been proven to be beneficial in improving the prognosis of patients with high risks of peritoneal dissemination of colon cancer. This study was performed to determine the comparative efficacy of intraperitoneal radioimmunotherapy (RIT) using Re-186 or I-131 labeled murine antibodies in the extermination of cancer cells. A murine anti-colorectal IgG1, A7 monoclonal antibody, was radio-labeled either with I-131 (by the chloramine-T method) or Re-186 (by the MAG3 pre-chelated method). A total number of 16 mice were subjected to RIT with Re-186 A7 (N=8) or I-131 A7 (N=8) at equitoxic doses in Balb/c bu/nu mice 10 min after intraperitoneal injection of LS180 human colon cancer cells. A third group of mice were subjected to chemotherapy with 5-fluorouracil at 30 mg/kg for 4 consecutive days following the intraperitoneal injection of the same LS180 human colon cancer cells. There were 19 mice in the control group who were not subjected to any form of therapy. The results revealed that the mean survival of mice in the control (N-19), I-131 A7 RIT (N=8) and Chemotherapy (N=6) groups were 33.8 ± 1.0, 80.1 ± 2.5 and 49.3 ± 5.3 days respectively. The eight mice who were subjected to Re-186 A7 RIT showed much better survival compared to the other groups. Two of the eight mice from this group died at 105 and 111 days following Re-186 A7 RIT. Other six mice were sacrificed at 172 days, and autopsy revealed no macroscopic peritoneal tumor growth. Based on this pilot study we concluded that individual tumor cells in the peritoneal cavity would be effectively exterminated by intraperitoneal RIT with Re-186 A7. (author)

  18. Radioimmunotherapy in refractory b-cell nonhodgkins lymphoma with I-131-labeled chimeric anti cd-20 c2b8 (I-131 rituximab): preliminary result

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hye Jin; Park, Yeon Hee; Kim, Sung Eun and others [Korea University Medical School, Seoul (Korea, Republic of)

    2005-07-01

    Recently, the native chimeric human-mouse anti CD-20 antibody IDEC-C2B8 (Rituximab) has been widely applied in NHL. This ongoing phase study was to evaluate whether radioimmunotherapy (RIT) with I-131 rituximab is effective in refractory B-cell NHL. Inclusion criteria were as follows: B-cell NHL with relapsed or refractory to primary standard therapy, measurable disease, adequate hematologic, renal, and hepatic function, informed consent. The rituximab (Mabthera, Roach) was radiolabeled with iodine-131(I-131) using a modified chloramine T method with high radiochemical purity (95%) and preservation of immuno-reactivity. All patients received loading doses of unlabeled rituximab (median, 40 mg: range, 20{approx}70 mg) immediately prior to administration of therapeutic dose (51.4{approx}152.2 MBq/kg), and then underwent gamma camera scan. 11 patients were enrolled (4 low-grade B-cell NHL, 7 DLBCL, median age 63 years). Patients had received a median of three prior chemotherapy regimens. The objective response rate was 36.4% (1 CR, 3 PRs). These all responses were observed in low-grade B-cell NHL, except one with DLBCL. Adverse events were primarily hematologic toxicities; the incidence of grade 3/4 neutropenia, thrombocytopenia, and anemia was 27.3%, 45.5%, and 18.2%, respectively. The treatment-related mortality was observed in one patient, who had been previously treated with high-dose chemotherapy plus TBI with autologous stem cell transplantation. RIT with I-131 rituximab seems to be effective tolerable in refractory low-grade B-cell NHL, although modest activity in refractory DLBCL. Further studies to define the efficacy of I-131 rituximab in DLBCL are warranted.

  19. Development of radioimmunoassay for the measurement of leptin in human serum

    International Nuclear Information System (INIS)

    Leptin is a 16 KDa polypeptide hormone encoded by the obese gene (ob) and secreted by adipose tissue. This hormone plays a major role in energy homeostasis and regulation of food intake and body weight. It also affects the metabolic, neuroendocrine, reproductive and haematopoietic systems. In this study, we report the development and validation of a radioimmunoassay for the quantitative measurement of human leptin in serum. Labeling of recombinant human leptin with 125I was best performed by the chloramineT method, specific activities of 2.8-3.3 MBq/μg were obtained. New Zealand white rabbits were immunized with recombinant human leptin and a highly specific polyclonal antibody was obtained without measurable cross-reaction as analysed using 10 different antigens. Concentrations of human leptin from serum samples were measured by a single overnight incubation assay with a sensitivity of 0.5 ng/mL and a measuring range of 0.5-100 ng/mL. Separation of bound and free fractions was performed with a magnetizable immunosorbent suspension and in the liquid phase assay separation was performed by using a 1mL mixture of anti-rabbit IgG (second antibody raised in sheep) and 8% PEG-solution after 20 minutes incubation at room temperature. Intra-assay and inter-assay imprecision (coefficient of variation) was < 6% and 8%, respectively. Recoveries of leptin in four human serum specimens serially diluted ranged from 88% to 106%. It was concluded that serum human leptin concentrations can be accurately and precisely measured by this novel radioimmunoassay procedure. Preliminary results obtained from the measurement of serum leptin in lean, overweight and obese patients are presented. Serum leptin concentrations correlated with Body Mass Index (BMI) and were significantly higher in women than in men. Such good correlation helped in the follow-up of the treated obese patients. (author)

  20. Preparation of monoclonal antibodies against cardiac myosin and some radiolabelling studies

    International Nuclear Information System (INIS)

    Monoclonal antibodies were raised against myosin, a specific indicator of myocardial infarction and labelled with 125I and 99mTc. Human cardiac myosin was isolated from normal human heart and was used for raising the monoclonal antibodies by the hybridoma technique. Antibody producing clones were identified by ELISA and cloning was done by the limiting dilution technique. Of the 13 clones obtained, 4 were deemed suitable for further studies. The antibodies were grown in ascites, purified, isotyped and their cross reactions with other forms of myosin were estimated. All the clones showed negligible cross reaction with rabbit myosin, but reacted to different extents with bovine skeletal myosin. The most avid antibody Mab-4G4 was chosen for further labelling studies. Mab-4G4 was labelled with 125I using different oxidising agents such as iodogen, chloramine-T and lactoperoxidase. Purified radioiodinated antibody with radiochemical purity >95% could be obtained by gel filtration. Immunoreactivity was retained as tested by binding to myosin immobilised on a solid support. Mab-4G4 was also labelled with 99mTc using stannous tartrate as the reducing agent. Radiolabelling yield was ∼60%, the purity was >95% and the immunoreactivity was retained. Both the labelled preparations were tested for bio-distribution in normal and infarcted rats. The activity accumulation in the infarcted region was ∼ 1.5 and 3.5 times as that in normal heart muscle for 125I and 99mTc labelled Mab-4G4 respectively. The major problem with the iodinated antibody was the in vivo deiodination resulting in very high percentage of activity in the thyroid. Although the fraction of the total activity associated with the infarcted heart is not very impressive, the fact that the activities with the infarcted and normal hearths are significantly different is heartening. With further optimisation of labelling and use of F(ab)'2 fragments, better delineation of the infarct sites is aspired. (author)

  1. Therapeutic efficacy of intralesional 131I-labelled hyaluronectin in grafted human glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Girard, N.; Courel, M.N.; Vera, P.; Delpech, B. [Centre Henri-Becquerel, Rouen (France). Laboratoire d' Oncologie Moleculaire

    2000-07-01

    The grafted human glioblastoma cell CB109 was used as a model for intralesional therapy with 131I-labelled hyaluronectin glycoprotein (131I-HN). 131I-HN bound specifically to in situ hyaluronic acid (HA), a main component of the extracellular matrix which is involved in tumour invasion. Labelling experimental conditions were determined and, finally, 25 {mu}Ci/{mu}gHN, 1 {mu}g chloramine-T/{mu}gHN and a 60-s stirring period provided a 131I-HN preparation with an optimal affinity for HA (64% compared to unlabelled HN). Following intratumoral injection, 131I-HN was retained with a limited diffusion outside the tumour. On day 4 the radioactivity concentrated in the tumour was still 25 times greater than that in the liver, spleen and kidneys combined. For therapeutic assays, 65 {mu}Ci 131I-HN was injected into the tumour, resulting in a delivery of 6.8 Gy over a 7-day period. Controls received unlabelled HN, heat-inactivated HN, a mixture of inactivated HN plus free 131I or no treatment (six animals per group). Tumour volumes were evaluated every second day from treatment day and the rate of tumour growth was expressed as a ratio of tumour size at time intervals to the tumour size at the time of injection. Growth curves were compared: heat-inactivated with or without free 131I had no anti-tumour effect. Unlabelled HN-injected tumours had a slightly slower growth rate than untreated tumours (p < 0.02) and growth rate of 131I-HN-injected tumours was much lower (p < 0.00002). A pronounced inhibitory effect with intralesional 131I-labelled HN injection resulted from a combination of a) blockage of HA, a proliferation facilitating factor, and b) local irradiation of tumoral tissue, while uptake in normal tissues was minimized.

  2. Harvard--MIT research program in short-lived radiopharmaceuticals

    International Nuclear Information System (INIS)

    This report describes progress on five projects. The first project showed a 1000 fold concentration of the cationic complex 99mTc (MIBI) in heart cell mitochondria vs heart cell cytoplasm, as determined by high resolution electron probe microanalysis. Additional technetium-99m based complexes are being developed and tested. The second project involves evaluating technetium acetylacteonates as potential indicators of cerebral blood flow. An intermediate in the synthesis of a technetium porphyrin complex has been synthesized; an oxotechnetium(V)-2,4-pentanedione complex has been prepared and is currently being characterized. The third project involves using radio labelled antibodies for diagnosis and treatment of cancer. An early discovery was that chloramine-T based iodination protocols resulted in a reversal of the charge on mouse lgGs. Immunoperoxidase-labelled monoclonal antibody MOv 18 was shown to bind specifically to the most frequent ovarian aderon carcinomas, and not to healthy tissue, making this antibody a good candidate for immunotherapy or immunodetection. Work on a specific immunotherapy protocol suffered a setback when one reagent, a 125I-biotin complex, proved to be unstable in vivo. The fourth project involves labelling antibodies with positron emitting radionuclides. Radiofluorination was accomplished through reductive alkylation of 18F-aldehyde, or pentafluorophenyl esters. Radioiodination was accomplished using alkyl-tin derivation exchange. The fifth project examined antibody modification for use in radioimmune imaging. Technetium-99m-labelled lgG was shown to be biologically equivalent to Indium-III-labelled lgG for imaging focal sites of inflamation. Also, Indium III labelling of small bioactive peptides was examined as a means of imaging important physiological processes. 44 refs., 2 figs

  3. Radioimmunoassay for human myoglobin: methods and results in patients with skeletal muscle or myocardial disorders

    International Nuclear Information System (INIS)

    A sensitive and specific radioimmunoassay has been developed for the measurement of serum Mb. Immunization of rabbit with human Mb yielded anti-Mb antibody which was purified by affinity chromatography. Human hemoglobin, CK, and the component of serum per se did not appear to cross-react with the antibody. Mb was radiolabeled by the chloramine T method. The radioimmunoassay method could detect as little as 0.3 ng of Mb and was not affected by hemolysis. Information is also given on precision, recovery, and specimen preservation. Mb levels could be detected in all of 120 normal adults, and the values ranged between 1 and 28 ng/ml (mean, 13.1 +- 6.1). No sex difference was observed. Levels were markedly elevated in all the patients with progressive muscular dystrophy, especially in the Duchenne type at the level of 40 to 1700 ng/ml. It was also noticed that about 70% of female gene carriers of Duchenne type had a slightly increased Mb level. An elevated serum Mb was also noted in polymyositis. In every case of acute myocardial infarction, serum Mb levels were increased, peak values ranging from 175 to 4400 ng/ml and averaging 1162 +- 287.9 Mb levels were elevated faster and peaked earlier (within 6 to 12 hr after the attack) than serum CK activity and returned to nearly normal range within 3 to 4 days. The increase in serum Mb was also noticed in shock and surgery. These data indicate that radioimmunoassay of Mb is a useful test for judging the myolytic state of myogenic myopathies and for early detection of myocardial infarction

  4. Development of radioiodine-labeled 4-hydroxyphenylcysteamine for specific diagnosis of malignant melanoma

    International Nuclear Information System (INIS)

    Introduction: A specific diagnosis for melanoma is strongly desired because malignant melanoma has poor prognosis. In a previous study, although radioiodine-125-labeled 4-hydroxyphenyl-L-cysteine (125I-L-PC) was found to have good substrate affinity for tyrosinase enzyme in the melanin metabolic pathway, 123/131I-L-PC had insufficient substrate affinity for tyrosinase to diagnose melanoma. In this study, we synthesized 4-hydroxyphenylcysteamine (4-PCA) and developed a novel radioiodine-125-labeled 4-hydroxyphenylcysteamine (125I-PCA) to increase affinity for the melanin biosynthesis pathway. Methods: 4-PCA was separated with 2-hydroxyphenylcysteamine (2-PCA), which is an isomer of 4-PCA, and was examined using melting point, proton nuclear magnetic resonance, mass spectrometry and elemental analysis. 125I-PCA was prepared using the chloramine-T method under no-carrier added conditions. We performed biodistribution experiments using B16 melanoma-bearing mice using 125I-PCA, 125I-L-PC, 125I-α-methyl-L-tyrosine, 123I-m-iodobenzylguanidine and 67Ga-citrate. In vitro assay was performed with B16 melanoma cells, and affinity for tyrosinase, DNA polymerase and amino acid transport was evaluated using phenylthiourea, thymidine, ouabine and L-tyrosine inhibitor. In addition, partition coefficients of 125I-PCA were evaluated. Results: In the synthesis of 4-PCA, analysis values did not differ between calculated and reported values, and 4-PCA was separated from 2-PCA at high purity. In biodistribution experiments, 125I-PCA was accumulated and retained in B16 melanoma cells when compared with 125I-L-PC. 125I-PCA showed the highest values at 60 min after radiotracer injection in melanoma-to-muscle ratios, melanoma-to-blood ratios and melanoma-to-skin ratios. Accumulation of 125I-PCA was significantly inhibited by phenylthiourea and thymidine. Partition coefficients of 125I-PCA were lower than those of N-isopropyl-p-[123I]iodoamphetamine and were not significantly different from

  5. Radioimmunoassay of protein C system

    International Nuclear Information System (INIS)

    Protein C system is an anticoagulation pathway which consists of protein C (PC), protein S (PS), thrombomodulator (TM) and protein C inhibitor (PCI). Using the McAb SZ-57, the authors have established SZ-57-Sepharose CL-6B affinity chromatography to purify human urinary TM. A procedure for isolation and purification of PC, PS and PCI from albumin-free human plasma by rivanol precipitation was also established. The isolation steps include adsorption onto and elution from barium, PEG precipitation, ion-exchange chromatography and preparative isoelectric focusing and so on. The molecular weight, isoelectric points, amino acid contents and the functional activity of these proteins were consistent with other previous reports. Four radioimmunoassays (RIAs) of PC, PS, TM and PCI were established using the equilibrium method. 125I-PC and 125I-PS were prepared using the chloramine-T method. 125I-PCI was prepared by iodogen method and 125I-TM by Bolton-Hunter method. Their sensitivities were 3.94 μg/L, 9.87 μg/L, 6.16 μg/L and 2.58 μg/L, respectively. The recovery rates were 104.28%, 94.30%, 105.22% and 101.89. Some antiserum provided a linear response from 6.25 to 1024 μg/L for PC, 21 to 700 μg/L for PS, 8.1 to 560 μg/L for TM and 4.8 to 1024 μg/L for PCI. The intra- and inter-assay CV were 4.4% and 9.68% for PC RIA, respectively, 4.99% and 13.14% for PS RIA, 5.10% and 10.94% for TM RIA, 2.73% and 8.62% for PCI RIA. The cross reactivity with factor II, thrombin, and antithrombin III was negligible. These methods can be used as effective tools especially for diagnosis of thrombosis and basic or clinical studies of protein C system. (20 refs., 8 figs., 6 tabs.)

  6. Structure and composition of arytenoid cartilage of the bullfrog (Lithobates catesbeianus) during maturation and aging.

    Science.gov (United States)

    Laureano, Priscila Eliane dos Santos; Oliveira, Kris Daiana Silva; de Aro, Andrea Aparecida; Gomes, Laurecir; Pimentel, Edson Rosa; Esquisatto, Marcelo Augusto Marretto

    2015-10-01

    The aging process induces progressive and irreversible changes in the structural and functional organization of animals. The objective of this study was to evaluate the effects of aging on the structure and composition of the extracellular matrix of the arytenoid cartilage found in the larynx of male bullfrogs (Lithobates catesbeianus) kept in captivity for commercial purposes. Animals at 7, 180 and 1080 days post-metamorphosis (n=10/age) were euthanized and the cartilage was removed and processed for structural and biochemical analysis. For the structural analyses, cartilage sections were stained with picrosirius, toluidine blue, Weigert's resorcin-fuchsin and Von Kossa stain. The sections were also submitted to immunohistochemistry for detection of collagen types I and II. Other samples were processed for the ultrastructural and cytochemical analysis of proteoglycans. Histological sections were used to chondrocyte count. The number of positive stainings for proteoglycans was quantified by ultrastructural analysis. For quantification and analysis of glycosaminoglycans were used the dimethyl methylene blue and agarose gel electrophoresis methods. The chloramine T method was used for hydroxyproline quantification. At 7 days, basophilia was observed in the pericellular and territorial matrix, which decreased in the latter over the period studied. Collagen fibers were arranged perpendicular to the major axis of the cartilaginous plate and were thicker in older animals. Few calcification areas were observed at the periphery of the cartilage specimens in 1080-day-old animals. Type II collagen was present throughout the stroma at the different ages. Elastic fibers were found in the stroma and perichondrium and increased with age in the two regions. Proteoglycan staining significantly increased from 7 to 180 days and reduced at 1080 days. The amount of total glycosaminoglycans was higher in 180-day-old animals compared to the other ages, with marked presence of

  7. Development of T3 radioimmunoassay kit

    International Nuclear Information System (INIS)

    Thyroxine T4 radioimmunoassay (RIA) kit has already been developed in this laboratory. For an efficient diagnosis of thyroid disease, however, it is well known that the T3 RIA should also be carried out in addition to the T4 RIA. Accordingly, the development of T3 RIA kit was urgently desired to match the T4 kit and to hold a sound domestic supply systems. The high specific activity T3125I about 3,000 μCi/μg T3) could be obtained by radioiodinating T2 with chloramine-T, and the labelled product could be stahilized. In the preparation of T3 free serum, charcoal was eliminated easily from serum by high speed centrifugation, and the resulting T3 free serum was used for the preparation of T3 standard serum solutions. RIA buffer system could be improved with the use of 0.025M barbital buffer, pH 8.2, containing 0.1% BSA, 0.5% bovine aamma globulin and 0.02% merthiolate. Antibody titer was increased threefold by using the 0.025M barbital buffer; the titer was 8,000: 1 in the 0.078M borbital buffer, pH 8.6, containing 0.1% BSA and 0.1% NaN3 while it was 26,000 : 1 in the above described 0.025M barbital buffer. The modified buffer system was also efficient for the use in T4 RIA since it increased the T4 antibody titer twofold. When the same buffer system was used in T3 RIA, no significant difference was observed between the use of HSA and of BSA in so far as 0.5% bovine gamma globulin was added to the buffer, contradicting those in the reference. The resalts indicated that the cost for the preparation of both kits can be saved. Quality guaranteed kits could be prepared by careful control of the assay values in comparing with those of the reference control sera. In consequence, there is not any technical difficulty in routine production. (Author)

  8. Development of anti-CD30 radioimmunoconstructs (RICs) for treatment of Hodgkin's lymphoma. Studies with cell lines and animal studies

    Energy Technology Data Exchange (ETDEWEB)

    Dietlein, M.; Boerner, S.M.; Fischer, T.; Zimmermanns, B.; Kobe, C.; Schicha, H.; Schomaecker, K. [Dept. of Nuclear Medicine, Univ. of Cologne (Germany); Hansen, H.; Schnell, R.; Tawadros, S.; Engert, A.; Staak, O.; Pogge von Strandmann, E. [Dept. of Internal Medicine I, Univ. of Cologne (Germany)

    2010-07-01

    Objectives: comparison of the binding affinity to a CD30-positive Hodgkin lymphoma (HL) cell line and biodistribution in HL bearing mice of new anti-CD30 radioimmunoconjugates (RICs) of varying structure and labelling nuclides. Methods: The antibodies Ki-4 and 5F11 were radioiodinated by the chloramine T method or labelled with {sup 111}In via p-NCS-Benzyl-DOTA. In addition, the Ki-4-dimer was investigated in the iodinated form. The RICs were analyzed for retained immunoreactivity by immunochromatography. In-vitro binding studies were performed on CD30-positive L540 cell lines. For in-vivo biodistribution studies, SCID mice bearing human HL xenografts were injected with the various radio-immunoconjugates. After 24 h, activities in the organs and tumour were measured for all 5 RICs. Tumour-free animals were studied in the same way with {sup 131}I-Ki-4 24 h p. i. The three RICs with the highest tumour/background ratios 24 h p.i. ({sup 131}I-Ki-4, {sup 131}I-5F11, {sup 111}In-bz-DOTA-Ki-4) were analysed further at 48 h and 72 h. Results: all the RICs were successfully labelled with high specific activities (28-47 TBq/mmol) and sufficient radiochemical yields (> 80%). Scatchard plot analysis proved high tumour affinity (K{sub D} = 20-220 nmol/l). In-vivo tumour accumulation in % of injected dose per g tissue (% ID/g) lay between 2.6 ({sup 131}I-5F11) and 12.3 % ID/g ({sup 131}I-Ki-4) with permanently high background in blood. Tumour/blood-ratios of all RICs were below one at all time points. Conclusions: in-vitro tumour cell affinities of all RICs were promising. However, in-vivo biokinetics tested in the mouse model did not meet expectations. This highlights the importance of developing and testing further new anti-CD30 conjugates. (orig.)

  9. New LHRH analogs for the detection of LHRH positive tumors

    International Nuclear Information System (INIS)

    Aim: Receptors for luteinizing hormone-releasing hormone (LHRH) can be found in various tumors including breast cancers as shown by previous studies on human specimens. Recently efforts were undertaken to target these receptors with cytotoxic peptide conjugates in experimental animal models (Schally et al.). However, LHRH receptor imaging in humans has not yet been reported. The aim of this study was to develop suitable analogs for this purpose and test the hypothesis that LHRH receptors can be detected and visualized by scintigraphic methods. Methods: Three radiolabeled analogs were prepared and evaluated in-vitro: Analog A is a radioiodinated derivative of the LHRH agonist D-Trp6-LHRH (Triptorelin). Analog B is a MAG-3 conjugate of D-Lys6-LHRH. (D-Lys6-LHRH is known to allow conjugation without substantial loss of receptor binding properties). Analog C is a HYNIC-conjugate of D-Lys6-LHRH. The latter 2 compounds allow for Tc-99m (and also Re-188) labeling. The iodinated compound was labeled using Chloramine-T methods and the Tc-labeled LHRH analogs were prepared by direct SnCl2 mediated labeling of the conjugates of chelator and peptide. (The conjugates were prepared using NHS-esters of the respective chelators, removal of protecting groups and final HPLC-purification.) High radiochemical yields and high specific activity can be obtained with all three compounds. However, first patient studies were carried out with the best characterized I-123-D-Trp6-LHRH. Results: Four patients (3 female, 1 male; mean age 53 y, 42-59) with newly diagnosed breast cancer underwent LHRH receptor scintigraphy after conventional imaging (US, mammography and MRI). After intravenous injection of 2-4 mCi HPLC-purified I-123-labeled D-Trp6-LHRH dynamic imaging was performed for 20 min with subsequent static imaging including whole body scans. The results were matched with conventional imaging. In 3/4 patients the breast cancer lesion was clearly visualized with tumoral tracer accumulation

  10. Development of a new radioimmunoassay for erythropoietin using recombinant erythropoietin

    Energy Technology Data Exchange (ETDEWEB)

    Mason-Garcia, M.; Beckman, B.S.; Brookins, J.W.; Powell, J.S.; Lanham, W.; Blaisdell, S.; Keay, L.; Li, S.C.; Fisher, J.W. (Tulane Univ. School of Medicine, New Orleans, LA (USA))

    1990-11-01

    The development of a 24 hour radioimmunoassay for erythropoietin (EPO) using EPO derived from recombinant DNA as both immunogen and ligand is described in the present paper. Mixed breed rabbits immunized with 10 micrograms/kg of EPO derived from a stably transfected cell line (MD) produced antibodies to EPO with high titer (up to 1:896,000 final dilution in the tube), high affinity (8.4 x 10(11) liter/M), and good specificity. Purified EPO from the above source or from AmGen Biologicals (AG) were successfully radioiodinated with the chloramine-T method and used as ligand in the radioimmunoassay. Standard dose-response curves prepared with EPO from both commercial sources were not significantly different and showed a sensitivity of 0.75 to 0.96 mU/tube. The dose-response curves in both systems also showed parallelism with serially diluted serum from a patient with aplastic anemia. Within-assay and between-assay precision were determined by assaying multiple replicates of a serum pool. Recovery of exogenous EPO added to a serum pool averaged 97% for both systems. The range of normal human serum EPO was determined by assaying the sera of 153 hematologically-normal adult subjects and was found to be 1.1 to 27.3 mU/ml for MD EPO and 0.5 to 16.7 mU/ml for AG EPO. Sera from several patients with hematologic abnormalities were also assayed, including those of 36 patients with anemia of end-stage renal disease (mean +/- SEM, 29.5 +/- 4.0 mU/ml; P less than 0.01). In conclusion, this new, more rapid and sensitive radioimmunoassay system can be used to measure EPO levels in sera from normal human subjects and patients with several types of anemia, and should also be very useful in therapeutic drug monitoring of patients receiving EPO from various commercial sources.

  11. Thrombus detection with a radiolabeled antiplatelet monoclonal antibody: Comparison with In-111-oxine technique in coronary and peripheral thrombi in dogs

    International Nuclear Information System (INIS)

    Platelets (P) labeled with low concentrations of an I-123 or In-111 labeled anti-P monoclonal antibody (7E3) were shown earlier to successfully image in-vivo thrombi. This study was carried out to compare this technique with In-111-oxine-P for localizing coronary and venous thrombi (CT and DVT) in dogs. Thrombi were induced using either transcatheter placement of a dacron pug, mechanical trauma, or electrocoagulation. 7E3 was labeled with I-131 in 70 +- 10% yield (labeling conditions: 100 μg 7E3; 5 μg chloramine T; I/sup -//7E3 ≤1; 2 min reaction; 200 μl pH 7 phosphate buffer; Sp. act. 10-30 μCi/μg). Binding of I-131-7E3 to dog P was 75 +- 10% after 1 hr incubation with whole blood. The dogs were injected with 0.5 mCi In-111-oxine-P and 1 mCi I-131-7E3-P in quick succession and data (blood clearance and imaging) were collected for 4 hr. In one experiment, DVT were clearly imaged within 10 min and CT in 30-60 min with I-131-7E3-P. In contrast, In-oxine-P required at least 30 min for imaging DVT and CT were only faintly visualized at 3-4 hr. The DVT to blood and CT to blood ratios at 2.4 hr were 16 and 12.3 for I-131-7E3-P and 9.4 and 6.5 for In-111-oxine-P respectively. In these preliminary studies, I-131-7E3-P thus appears to be superior to In-oxine-P for imaging venous and coronary thrombi. Additionally, 7E3 can be labeled with Tc-99m and I-123 for reduced dose and better imaging properties

  12. Functional expression of a single-chain antibody to ErbB-2 in plants and cell-free systems

    Directory of Open Access Journals (Sweden)

    Benevolo Maria

    2006-09-01

    Full Text Available Abstract Background Aberrant signaling by ErbB-2 (HER 2, Neu, a member of the human Epidermal Growth Factor (EGF receptor family, is associated with an aggressive clinical behaviour of carcinomas, particularly breast tumors. Antibodies targeting the ErbB-2 pathway are a preferred therapeutic option for patients with advanced breast cancer, but a worldwide deficit in the manufacturing capacities of mammalian cell bioreactors is foreseen. Methods Herein, we describe a multi-platform approach for the production of recombinant Single chain Fragments of antibody variable regions (ScFvs to ErbB-2 that involves their functional expression in (a bacteria, (b transient as well as stable transgenic tobacco plants, and (c a newly developed cell-free transcription-translation system. Results An ScFv (ScFv800E6 was selected by cloning immunoglobulin sequences from murine hybridomas, and was expressed and fully functional in all the expression platforms, thereby representing the first ScFv to ErbB-2 produced in hosts other than bacteria and yeast. ScFv800E6 was optimized with respect to redox synthesis conditions. Different tags were introduced flanking the ScFv800E6 backbone, with and without spacer arms, including a novel Strep II tag that outperforms conventional streptavidin-based detection systems. ScFv800E6 was resistant to standard chemical radiolabeling procedures (i.e. Chloramine T, displayed a binding ability extremely similar to that of the parental monovalent Fab' fragment, as well as a flow cytometry performance and an equilibrium binding affinity (Ka approximately 2 × 108 M-1 only slightly lower than those of the parental bivalent antibody, suggesting that its binding site is conserved as compared to that of the parental antibody molecule. ScFv800E6 was found to be compatible with routine reagents for immunohistochemical staining. Conclusion ScFv800E6 is a useful reagent for in vitro biochemical and immunodiagnostic applications in oncology

  13. A radioimmunoassay for erythropoietin: serum levels in normal human subjects and patients with hemopoietic disorders

    Energy Technology Data Exchange (ETDEWEB)

    Rege, A.B.; Brookins, J.; Fisher, J.W.

    1982-12-01

    An RIA for Ep has been developed that is highly sensitive and specific. A homogeneous Ep preparation was labeled with /sup 125/I by the chloramine-T method to a specific activity of 90 to 136 ..mu..Ci/..mu..g and immunoreactivity of 80%. Ep antiserum, which was produced to a human urinary Ep preparation (80 U/mg of protein), was adsorbed with normal human urinary and serum proteins without any loss in sensitivity of the RIA to increase the specificity of the assay. A good correlation was seen between the RIA and the exhypoxic polycythemic mouse assay (corr. coef. 0.967; slope 1.05 and ''y'' intercept 0.75). Ep titers in sera from 175 hematologically normal human subjects exhibited a normal frequency distribution and ranged between 5.8 and 36.6 mU/ml with a mean of 14.9 +/- 4.7 (S.D.) and median of 14.3. Serum Ep titers were markedly elevated in seven patients with aplastic anemia and one patient with pure red cell aplasia (1350 to 20,640 mU/ml) and were lower than normal in two patients with polycythemia vera (8.1 and 9.4 mU/ml). The serum Ep titers in a prenephrectomy patient with chronic glomerulonephritis (31.1 mU/ml) decreased to below normal levels (9.04 mU/ml) after nephrectomy. The cord serum erythropoietin titers in 10 IDM (90.82 +/- 134.1 (S.D.) mu/ml) returned to values within the normal range (13.86 +/- 5.55) on day 3 after birth, suggesting the utility of the RIA in elucidating the role of hypoxia and/or insulin in increased erythropoiesis in IDM. The serum Ep titers in patients with anemias and polycythemias were compared to those of normal human subjects and agreed well with pathophysiologic mechanisms of these hemopoietic disorders, confirming the validity of the RIA.

  14. A radioimmunoassay for erythropoietin: serum levels in normal human subjects and patients with hemopoietic disorders

    Energy Technology Data Exchange (ETDEWEB)

    Rege, A.B.; Brookins, J.; Fisher, J.W.

    1982-12-01

    An RIA for Ep has been developed that is highly sensitive and specific. A homogeneous Ep preparation was labeled with /sup 125/I by the chloramine-T method to a specific activity of 90 to 136 micro Ci/microgram and immunoreactivity of 80%. Ep antiserum, which was produced to a human urinary Ep preparation (80 U/mg of protein), was adsorbed with normal human urinary and serum proteins without any loss in sensitivity of the RIA to increase the specificity of the assay. A good correlation was seen between the RIA and the exhypoxic polycythemic mouse assay (corr. coef. 0.967; slope 1.05 and y intercept 0.75). Ep titers in sera from 175 hematologically normal human subjects exhibited a normal frequency distribution and ranged between 5.8 and 36.6 mU/ml with a mean of 14.9 +/- 4.7 (S.D.) and median of 14.3 Serum Ep titers were markedly elevated in seven patients with aplastic anemia and one patient with pure red cell aplasia (1350 to 20,640 mU/ml) and were lower than normal in two patients with polycythemia vera (8.1 and 9.4 mU/ml). The serum Ep titers in a prenephrectomy patient with chronic glomerulonephritis (32.1 mU/ml) decreased to below normal levels (9.04 mU/ml) after nephrectomy. The cord serum erythropoietin titers in 10 IDM (90.82 +/- 134.1 (S.D.) mu/ml) returned to values within the normal range (13.86 +/- 5.55) on day 3 after birth, suggesting the utility of the RIA in elucidating the role of hypoxia and/or insulin in increased erythropoiesis in IDM. The serum Ep titers in patients with anemias and polycythemias were compared to those of normal human subjects and agreed well with pathophysiologic mechanisms of these hemopoietic disorders, confirming the validity of the RIA.

  15. Distribution of 131 I- labeled Bothrops erythromelas venom in mice

    International Nuclear Information System (INIS)

    Bothrops erythromelas is responsible for many snake bites in northeastern Brazil. In the present study we determined the in vivo distribution of the venom following its subcutaneous injection into mice. B. erythromelas venom and albumin were labeled individually with 131 I by the chloramine T method, and separated in a Sephacryl S-200 column. The efficiency of labeling was 68%.Male Swiss mice (40-45 g), which had been provided with drinking water containing 0.05% KI over a period of 10 days prior to the experiment, were inoculated dorsally (sc) with 0.3 ml (2.35 x 105 cpm/mouse) of 131 I-venom (N = 42), 131 -albumin or 131 I (controls, N = 28 each). Thirty minutes and 1,3, 6, 12, 18 and 24 h after inoculation, the animals were perfused with 0.85% Na Cl and skin and various organs were collected in order to determine radioactivity content. There was a high rate of venom absorption int he skin (51%) within the first 30 min compared to albumin (20.1%) and free iodine (8.2%). Up to the third hour after injection there was a tendency for venom and albumin to concentrate in the stomach ( 3 rd h),small intestine (3 rd h) and large intestine (6th h). Both control groups had more radioactivity in the digestive tract, especially in the stomach, but these levels decreased essentially to baseline by 12-18 h postinjection. In the kidneys, the distribution profiles of venom, albumin and iodine were similar. Counts at 30 min postinjection were low in all three groups (1.37, 1.86 and 0.77, respectively), and diminished to essentially 0% by 12-18 h. Albumin tended to concentrate in muscle until the 3 rd h postinjection (1.98%).There was a low binding of labeled venom in the liver (B. erythromelas venom does not specifically target most internal organs. That is, the systemic effects of envenomation ar mainly due to an indirect action. (author)

  16. Synthesis and evaluation of iodine-123 labelled tricyclic tropanes as radioligands for the serotonin transporter

    Energy Technology Data Exchange (ETDEWEB)

    Quinlivan, Mitchell; Mattner, Filomena; Papazian, Vahan; Zhou, Jia; Katsifis, Andrew; Emond, Patrick; Chalon, Sylvie; Kozikowski, Alan; Guilloteau, Denis; Kassiou, Michael E-mail: mkassiou@med.usyd.edu.au

    2003-10-01

    The tricyclic tropane analogues (1S,3S,6R,10S)-(Z)-10-(benzoyloxymethyl)-9-(3-chloro-4-iodobenzylidene)-7 -azatricyclo[4.3.1.0{sup 3,7}]decane, 1, and (1S,3S,6R,10S)-(Z)-9-(3-chloro-4-iodobenzylidene)-7-azatricyclo[4.3.1.0{sup 3,7}] = decane-10-carboxylic acid methyl ester, 2, have been shown to be potent and selective serotonin transporter (SERT) ligands. They possess nanomolar affinity for the SERT (Ki = 0.06 nM and 1.8 nM respectively) and are suitable for radiolabelling using iodine-123. In the present study we prepared [{sup 123}I]1 and [{sup 123}I]2 from the appropriate tributylstannane precursors using acidic media with chloramine-T as the oxidising agent. The radiochemical yield obtained for [{sup 123}I]1 varied between 50-60% while for [{sup 123}I]2 the range was 65-80%. Both radioligands were obtained with radiochemical purity > 97% and specific activity estimated to be > 185 GBq/{mu}mol. The biodistribution of [{sup 123}I]1 demonstrated low degree of brain penetration at 5 min (0.14%ID/g) with a homogenous distribution. The radioactivity cleared quickly from all brain regions with no preferential localization. In comparison, [{sup 123}I]2 demonstrated on average a higher brain uptake at 5 min (0.5%ID/g). However the distribution of radioactivity was homogenous and cleared to levels similar to [{sup 123}I]1 at 1 hr post-injection. Pre-administration of citalopram failed to show any significant inhibition of [{sup 123}I]2 uptake in the rat brain. The high lipophilicity of 1 and 2 (HPLC-derived log P{sub 7.4} values of 6.41 and 4.25 respectively) and in vivo metabolism, seen by high thyroid uptake would explain the absence of any specific binding observed in the rat brain. In view of these results [{sup 123}I]1 and [{sup 123}I]2 do not appear to be suitable radioligands for in vivo studies of the SERT.

  17. Synthesis, in vitro binding, and tissue distribution of radioiodinated 2-[{sup 125}I]N-(N-benzylpiperidin-4-yl)-2-iodo benzamide, 2-[{sup 125}I]BP: a potential {sigma} receptor marker for human prostate tumors

    Energy Technology Data Exchange (ETDEWEB)

    John, Christy S.; Gulden, Mary E.; Li, Jinghua; Bowen, Wayne D.; McAfee, John G.; Thakur, Mathew L

    1998-04-01

    The preclinical evaluation of a {sigma} receptor-specific radiopharmaceutical that binds to human prostate tumor cells with a high affinity is described. We have synthesized and radioiodinated 2-[{sup 125}I]-N-(N-benzylpiperidin-4-yl)-2-iodobenzamide (2-[{sup 125}I]BP) that possesses high affinity for both {sigma}-1 and {sigma}-2 receptor subtypes that are expressed on a variety of tumor cells. 2-IBP was synthesized, purified and characterized by routine spectroscopic and analytical methods. Radioiodination was accomplished using an oxidative iododestannylation reaction in the presence of chloramine T in high yields (76%-93%) with a very high-specific activity (1700-1900 Ci/mmol). The in vitro competition binding studies of 2-[{sup 125}I]BP with various {sigma} receptor ligands in LnCAP human prostate tumor cells showed a dose-dependent saturable binding. The inhibition constants (K{sub i}, nM) for binding of 2-[{sup 125}I]BP to human prostate tumor cells for 4-IBP, haloperidol and 2-IBP were 4.09, 6.34 and 1.6 nM, respectively. The clearance of 2-[{sup 125}I]BP, in Sprague-Dawley rats, was rapid from the blood pool, other normal tissues and the total body. Tissue distribution studies in nude mice bearing human prostate tumor (DU-145) also showed a fast clearance from normal organs. The tumor had the highest percentage of injected dose per gram (%ID/g) of all tissues at 4 h as well as 24 h (2.0 {+-} 0.05 and 0.147 {+-} 0.038 ID/g, respectively) postinjection. The in vivo receptor binding specificity was demonstrated using haloperidol (a known high-affinity {sigma} receptor ligand). A significant decrease (>50%, p = 0.001) was observed in tumor concentration when haloperidol was used as a blocking agent. The high affinity of 2-[{sup 125}I]BP for {sigma} receptor-binding sites, its fast in vivo clearance from normal organs and its high uptake and retention in tumor implies that 2-[{sup 123}I]BP or 2-[{sup 131}I]BP may be a promising tracer for noninvasive imaging of

  18. Synthesis and evaluation of [{sup 123}I] ligands for the study of the peripheral benzodiazepine receptors using SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Mattner, F.; Katsifis, A.; Mardon, K.; Papazian, V.; Najdovski, L.; Dikic, B. [Australian Nuclear Science and technology Organisation, Lucas Heights, Sydney, NSW (Australia). Radiopharmaceuticals Division

    1998-06-01

    Full text: The peripheral benzodiazepine receptors (PBR), are distinct from the central benzodiazepine receptors in their pharmacology and subcellular location. PBR`s are predominantly found in the peripheral organs such as kidney, heart, adrenal cortex, as well as in the glial cells in the brain. PBR`s have been implicated in the control of cell proliferation and differentiation and shown to display increased levels in a variety of malignant tumours. Increased levels of PBR`s have also been implicated in a variety of neurodegenerative disorders. We have prepared and evaluated [{sup 123}I]N`N`-dimethyl-6-methyl-(4`iodophenyl) midazo[l,2-a]pyridine-3-acetamide (1), [{sup 123}I]N`N`-diethyl-6-chloro-(4`iodophenyl) imidazo[l,2-a]pyridine-3-acetamide (2) and [{sup 123}l]3-benzoimidomethyl-2- (4`-t-butylphenyl)-6-iodoimidazo[1,2-b]pyridazine (3) as potential probes for the study of the PBR`s in oncology and neurodegeneration using SPECT. The iodine-123 analogues 1 and 2 were prepared by iododestannylation with Na {sup 123}I in the presence of chloramine-T and HCI. Compound 3 was prepared from the bromo precursor with Na {sup 123}I using Cu{sup +} assisted halogen exchange. In vivo biodistribution of all three compounds in rodents indicated high uptake in tissues with known PBR sites. Pre-treatment of the rats with PK 11195, Ro 5-4864 and the cold material reduced significantly the uptake of activity in organs expressing the PBR`s. Other drugs including flumazenil and haloperidol, did not significantly reduce the uptake of activity in these organs. Metabolite studies on 1 and 2 indicated high in vivo stability, however significant deiodination in vivo was observed for 3. In conclusion, ligands 1, 2 and 3 indicated high and selective in vivo uptake in organs expressing the PBR whereas ligand 3 had reduced in vivo stability. Compounds 1 and 2 are therefore suitable candidates for further development as ligands for the study of the PBR`s using SPECT

  19. Synthesis, in vitro validation and in vivo pharmacokinetics of [125I]N-[2-(4-iodophenyl)ethyl]-N-methyl-2-(1-piperidinyl) ethylamine: A high-affinity ligand for imaging sigma receptor positive tumors

    International Nuclear Information System (INIS)

    N-[2-(4-iodophenyl)ethyl]-N-methyl-2-(1-piperidinyl)ethylamine, IPEMP, and the corresponding bromo derivative, BrPEMP, have been synthesized and characterized. Both BrPEMP and IPEMP were evaluated for sigma-1 and sigma-2 subtype receptor affinities and found to possess very high affinities for both receptor subtypes. The precursor for radioiodination n-tributylstannylphenylethylpiperidinylethylamine was prepared from its bromo derivative by palladium-catalyzed stannylation reaction. Radioiodinated 4-[125I]PEMP was readily prepared in high yields and high specific activity by oxidative iododestannylation reaction using chloramine-T as oxidizing agent. Sites labeled by 4-[125I]PEMP in guinea pig brain membranes showed high affinity for BD1008, haloperidol, and (+)-pentazocine (Ki = 5.06 ± 0.40, 32.6 ± 2.75, and 48.1 ± 8.60 nM, respectively), which is consistent with sigma receptor pharmacology. Competition binding studies of 4-[125I]PEMP in melanoma (A375) and MCF-7 breast cancer cells showed a high affinity, dose-dependent inhibition of binding with known sigma ligand N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl) ethylamine, BD1008 (Ki = 5, 11 nM, respectively), supporting the labeling of sigma sites in these cells. Haloperidol, however showed a weaker (Ki 100-200 nM) affinity for the sites labeled by 4-[125I]PEMP in these cells. Biodistribution studies of 4-[125I]PEMP in rats showed a fast clearance of this radiopharmaceutical from blood, liver, lung, and other organs. A co-injection of 4-IPEMP with 4-[125I]PEMP resulted in 37%, 69%, and 35% decrease in activity in liver, kidney, and brain (organs possessing sigma receptors), respectively at 1-h postinjection. These results suggest that 4-[125I]PEMP is a promising radiopharmaceutical for pursuing further studies in animal models with tumors

  20. Synthesis, in vitro binding, and tissue distribution of radioiodinated 2-[125I]N-(N-benzylpiperidin-4-yl)-2-iodo benzamide, 2-[125I]BP: a potential σ receptor marker for human prostate tumors

    International Nuclear Information System (INIS)

    The preclinical evaluation of a σ receptor-specific radiopharmaceutical that binds to human prostate tumor cells with a high affinity is described. We have synthesized and radioiodinated 2-[125I]-N-(N-benzylpiperidin-4-yl)-2-iodobenzamide (2-[125I]BP) that possesses high affinity for both σ-1 and σ-2 receptor subtypes that are expressed on a variety of tumor cells. 2-IBP was synthesized, purified and characterized by routine spectroscopic and analytical methods. Radioiodination was accomplished using an oxidative iododestannylation reaction in the presence of chloramine T in high yields (76%-93%) with a very high-specific activity (1700-1900 Ci/mmol). The in vitro competition binding studies of 2-[125I]BP with various σ receptor ligands in LnCAP human prostate tumor cells showed a dose-dependent saturable binding. The inhibition constants (Ki, nM) for binding of 2-[125I]BP to human prostate tumor cells for 4-IBP, haloperidol and 2-IBP were 4.09, 6.34 and 1.6 nM, respectively. The clearance of 2-[125I]BP, in Sprague-Dawley rats, was rapid from the blood pool, other normal tissues and the total body. Tissue distribution studies in nude mice bearing human prostate tumor (DU-145) also showed a fast clearance from normal organs. The tumor had the highest percentage of injected dose per gram (%ID/g) of all tissues at 4 h as well as 24 h (2.0 ± 0.05 and 0.147 ± 0.038 ID/g, respectively) postinjection. The in vivo receptor binding specificity was demonstrated using haloperidol (a known high-affinity σ receptor ligand). A significant decrease (>50%, p = 0.001) was observed in tumor concentration when haloperidol was used as a blocking agent. The high affinity of 2-[125I]BP for σ receptor-binding sites, its fast in vivo clearance from normal organs and its high uptake and retention in tumor implies that 2-[123I]BP or 2-[131I]BP may be a promising tracer for noninvasive imaging of human prostate tumors

  1. Monoclonal antibody RM2 as a potential ligand for a new immunotracer for prostate cancer imaging

    International Nuclear Information System (INIS)

    Objectives: To investigate the potential of monoclonal antibody (mAb) RM2 as a ligand for a radioimmunotracer for prostate cancer imaging. Methods: Labeling was conducted with mAb RM2 and 125I using the chloramine-T method. The cell study was conducted with PC-3 and LNCaP, which are prostate cancer cell lines, and MCF-7, which is a breast cancer cell line. The cells were treated or untreated with unlabeled mAb RM2 to block the haptoglobin-β chains expressed on the surface of the prostate cancer cells. 125I-mAb RM2 was added into the cell culture media and cellular uptake of 125I-mAb RM2 was evaluated at 1, 3 and 6 hours of incubation. For the in vivo biodistribution study, PC-3 cells were implanted in athymic male mice. The animals were injected intravenously with 125I-mAb RM2. At 24, 48 and 72 hours after tracer injection, the animals were sacrificed and the activity levels of blood and tissue samples were determined. Results: The uptake of 125I-mAb RM2 in the PC-3 and LNCaP cells increased according to the incubation time, while the uptake of 125I-mAb RM2 in MCF-7 cells did not show any increase up to 6 hours. The increase of 125I-RM2 uptake was not observed when the PC-3 and LNCaP cells were pre-treated with unlabeled RM2. In the biodistribution studies, 125I-mAb RM2 showed marked uptake into the implanted PC-3 cells. In PC-3 tumor-bearing mice, the tumor muscle ratio of 125I-RM2 was increased for up to 72 hours in a time-dependent manner. Conclusions: 125I-mAb RM2 showed excellent prostate cancer cell targeting in vitro and in vivo. Therefore, mAb RM2 seems to be a potential candidate for an immunoligand for prostate cancer imaging.

  2. Comparative Studies on the Radiolabeling and Chromatographic Purification of Some Medically Important Compounds

    International Nuclear Information System (INIS)

    The present thesis comprises five basic chapters: The first chapter includes the main idea of our study and its problems, also includes the aim of the work of our study. The second chapter includes the theoretical consideration of the subject. It deals with the general methods of labeling, factors that influence the integrity of labeled compounds, radionuclides used for diagnostic nuclear medicine, production methods and radioactive properties of 123I, 125I and 131I. It includes also the techniques used for the preparation of the radioiodinated compounds especially the electrophilic radioiodination technique. This chapter deals also with the medical imaging, techniques of diagnostic nuclear medicine and the purification of radioiodinated compounds using different chromatographic techniques. Since these radioiodinated compounds are used for diagnosis and therapeutic treatment of human diseases, quality control tests such as determination of chemical purity, radionuclidic purity, radiochemical purity, sterility, pyrogenicity and biodistribution are performed to ensure the purity, the safety and efficiency of these products for the intended nuclear medicine application. The third chapter describes the experimental section; comprising chemicals, reagents, the radionuclides, the equipments and the counting systems used in the study. It describes the electrophilic radioiodination using chloramine-T (CAT), iodogen and lactoperoxidase oxidizing agents and the factors affecting the radiochemical yield of the radioiodination of histamine and L-tyrosine methyl ester such as substrate concentration, ph of the medium, reaction time, temperature and stability of the labeled product. This chapter also includes the techniques used in the Purification of radioiodinated compounds, including paper electrophoresis, thin layer chromatography (TLC), Poly acrylamide-acrylic acid resin [P(AAm-AA) resin] and high performance liquid chromatography (HPLC), in addition, the quality control

  3. Radioiodination and biodistribution of the monoclonal antibody TU-20 and its scFv fragment

    International Nuclear Information System (INIS)

    The ability of the monoclonal antibody TU-20 and its scFv fragment to bind specifically to the C-end of the class III β-tubulin makes these substances useful as potential diagnostics for neurodegenerative diseases-especially peripheral neuropathies. TU-20 and its scFv were labeled with 125I and 123I by chloramine-T (with radiochemical yield 75 and 50%, respectively). Radiochemical purity and stability was revealed by gel filtration (decrease to 80 and 50% in 2 months, respectively). Immunoreactivity of the labeled TU-20 was determined by ELISA - the range of the preserved immunoreactivity varies from 60 to 95% in accordance to the used radiolabeling process. RIA and affinity coupling analytic methods were specifically designed with focusing on specifics of the antibody and its fragment. The results of RIA differ in dependence on the type of the reaction vessel (glass or polystyrene) and the affinity coupling results depend on the experimental arrangement - in the batch or on the column. Fragmentation of the labeled antibody and its fragment was estimated by bis-tris gel electrophoresis followed by silver staining and autoradiography (over 95% of radioactivity bound in the substances). The antibody binding in tissue slices was studied in vitro by immunohistochemistry. The Purkinje cells were observed conjugated with the radiolabeled substances, either TU-20 or its ScFv fragment in the area of the cerebellum. In vivo biodistribution of 125I-TU-20, 125I-scFv TU-20, 123I-scFv TU-20 and Na125I was proceeded in normal mice (wild type C57B/6/J). Both biomolecules labeled by 123I were also proved in an imaging biodistribution study with use of the SPECT camera. Finally, a transgene population G93A1 Gur was used for comparative study to show the different behaviour of the substances in a normal mouse and in the modified organism with amyotrophic lateral sclerosis. The most part of differences is observed in the area of the muscles, rostal and caudal spinal cord. In summary

  4. Preparation of the radiopharmaceutical 131I-Anti-CD20 for the treatment of lymphomas

    International Nuclear Information System (INIS)

    At the present time they are considered to the lymphomas like a problem of first magnitude since has happened it is necessary to be the fifth cancer cause in the world. Different treatments focused to the lymphoma like the chemotherapy and the radiotherapy, have been employees to counteract the No-Hodgkin lymphoma, without these they don't exclude the healthy tissue of the toxicity. It is for it that is taking a new direction with the employment of the directed radioimmunotherapy since this it allows to kill wicked cells selectively with radiation dose joined to the apoptosis and cytotoxicity induced by the own one bio molecule. The radioimmunotherapy with radiolabelled antibodies directed to the surface antigen CD20 represents a new modality for the treatment of No-Hodgkin lymphoma and potentially other illnesses. In this work the parameters of optimization are presented for the preparation, control of quality and evaluation of the stability in vitro and in vivo of the monoclonal antibody anti-CD20 labelled with 131 I for the treatment of No-Hodgkin lymphoma. The anti-CD20 labelled by the chloramine-T method with high radiochemical purity (>98%), it is stable in solution for but of a half life of the radionuclide (8.04 days) The 131 I-anti-CD20 doesn't present dehalogenation in vitro (human serum) during 24 h of incubation at 37 C. According to the tests carried out to establish the immunoreactivity, a percentage of union to cells was obtained (B lymphocytes) bigger to 30%. The biodistribution in mice balb/c one hour after their administration, it shows that there is not high reception in mucous neither kidneys, what indicates that the complex is stable in vivo. In conclusion, the radiopharmaceutical 131 I-anti-CD20 was obtained in sterile injectable solution and free of pyrogens with a radiochemical purity bigger to 98% and a specific activity of 296 MBq. The radiolabelled molecule maintains its biological recognition for the receiving CD20 highly expressed in

  5. Estimation of progesterone in bovine milk by liquid phase radioimmunoassay for veterinary applications

    International Nuclear Information System (INIS)

    Full text: Reproductive management is a major concern for the dairy industry which, with inefficient estrous detection, causes significant economic loses. The level of progesterone, which is a steroid hormone of molecular weight 314.5 D, as an early indicator of pregnancy, is becoming increasingly popular. This now has become an essential tool for the veterinarians and the farmers in making early diagnosis and decisions on culling and rebreeding for economic herd management. The standardization of a direct radioimmunoassay for the estimation of progesterone in bovine milk using 125I-labelled progesterone prepared by radio iodinating the tyrosine methyl ester (TME) conjugated to progesterone and a specific antibody is described. The conjugate was radioiodinated with 125I using chloramine-T and purified by gel-filtration. Radiochemical purity of the tracer was found to be >98%. A set of seven individual progesterone standards in buffer was prepared in lyophilized form. Milk samples for the preparation of progesterone free milk was collected during the heat period. After checking for the non-specific binding and specific binding, in these samples, they were further processed. Potassium dichromate was added to these samples for prolonged storage. Further, the milk was skimmed by centrifuging at 2000g for 15 minutes. Various assay parameters, such as, buffer, volume of the matrix, milk/sample/standard, incubation condition, total reaction volume, and separation system were studied in detail to optimize the assay. Non-specific binding was found to be <5% and specific binding was found to be 30-50%. No blocking agents were added in the milk sample during the assay. The assay involves the incubation of progesterone antibody along with individual standards or sample and radiolabelled tracer for 2 hours at room temperature. The assay range was 0-50ng/ml where the volume of standard/sample was 50μl. The developed assay was further validated where the intra and inter assay

  6. Biochemical and pharmacological studies of native and irradiated crotamine with gamma radiation of 60Co

    International Nuclear Information System (INIS)

    Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. This has been employed to attenuate animal toxins. Crotamine is a strongly basic polypeptide from the South American rattlesnake venom, composed of 42 amino acid residues. It induces skeletal muscle spasms leading to a spastic paralysis of hind limbs in mice. The objective of this thesis was carry out biochemical and pharmacological studies of native and irradiated crotamine with 60 Co. Crotamine was purified from Crotalus durissus terrificus venom by Sephadex G-100 gel filtration followed by ion exchange chromatography, using a Fast Performance Liquid Chromatography (FPLC) system. It was irradiated at 2 mg/ml in 0.15 M Na Cl with 2.0 kGy gamma radiation emitted by a 60 Co source. The native and irradiated crotamine were evaluated by biochemical characterization, toxic activity (LD50 and biodistribution. The native and irradiated crotamine were labelled with 29.6 MBq of 125 I using chloramine T method, and separated in a Sephadex G-50 column. Male Swiss mice (35± 5 g), were injected i.p. with o.1 mL (2.4 x 106 cpm/mouse) of 125 I native crotamine or with 0.4 mL (1.3 x 106 cpm/mouse) of 125 I irradiated crotamine. At 0.08; 0.25; 0.5; 1; 2; 4; 8; 12 and 24 hours the animal were killed by ether inhalation. Blood, spleen, liver, kidneys, brain, lungs, heart, and skeletal muscle were collected in order to determine radioactivity content. The results showed that gamma radiation did not change the protein concentration, the electroforetic profile or the primary structure of the protein, although differences were shown by spectroscopic techniques. The gamma radiation diminished the toxicity of crotamine, but it did not abolish bioactivity. Biodistribution studies showed that native and irradiated crotamine have hepatic metabolism and renal elimination. The native and irradiated crotamine have affinity by skeletal muscle and they did not pass the blood - brain

  7. Relation between human myocardial acidic isoferritin and hepatoma

    International Nuclear Information System (INIS)

    Acid iso ferritin (AIF), a ferritin isomer with a high proposition of H subunit, is different from basic iso ferritin (BIF) biochemically and immunologically. AIF was isolated and purified from human myocardium and the antiserum was obtained by immunizing the rabbits. A radioimmunoassay (RIA) of AIF and an immunoradiometric assay of AIF-H subunit were established by preparing 125I-AIF and 125I-AIF-H McAb using the chloramine-T method. The intra-and inter-assay CV of AIF RIA were 1.65% and 9.71%, respectively. The recovery rate was 102%. The antiserum provided a linear response from 7.0∼369.6μg/L, with ED50 of 27.50 μg/L. AIF-H IRMA methodological study found that the intra- and inter- assay CV were 2.44% and 10.16%, respectively. The sensitivity was 0.74 μg/L, the recovery rate was 92.29% and ED50 was 23.05 μg/L. The cross-reactivity of the two assays with AFP, CEA and lactoferrin was negligible, while that with BIF was 1.74% and 3.13%, respectively. The serum AIF concentration showed a considerable variation in different sexes and age groups. Its sensitivity for diagnosis of hepatic cancer was 73.05%, independent on the severity of hepatic injury. In eight kinds of malignant tumors studied, AIF was found to be most valuable in diagnosis of hepatic cancer, with its positive, negative false-positive and false-negative rates being all ideal. The patients with hepatoma had increased concentration of serum AIF-H subunit, so measuring the ratio of H/L subunits was valuable for studying the diseases. These results suggest that AIF may turn to be a rather specific index of hepatic cancer. Combination of monitoring both AIF and AFP would raise the rate of detection of positive cases and improve the specificity of method for the diagnosis of hepatic cancer. (15 refs., 4 figs., 6 tabs.)

  8. Modulation of the Pharmacological and Biochemical Actions of Leiurusquinquestriatus (L.q Scorpion Venom by Exposure to Gamma Radiation

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    Heba A. Mohamed*, Esmat A. Shaaban* , Aber M Amin** and Sanaa A. Kenawy

    2011-07-01

    Full Text Available This study was undertaken to evaluate the effect of gamma radiation (1.5 KGy & 3 KGy on L.q scorpion venom. This was carried out by studying the toxicological, biochemical & immunological properties of the venom before and after exposure to gamma radiation. Material and methods Animals, venom, antivenin, gamma radiation, 125I. Results Data revealed that the toxicity of irradiated venom (1.5 KGy & 3 KGy decreased as compared to that of the native one. LD50 of irradiated venom were 3.5 mg/kg & 7.5 mg/kg respectively while, that of the native venom was (0.39 mg/kg. Moreover, the distribution of 125I-labeled L.q venom was studied in male Swiss mice tissue using chloramine-T method by being injected intravenously. At various time intervals, urine and blood were collected and the animals were sacrificed. Brain, lungs, heart, liver, kidneys, spleen, intestine, bone and muscle were isolated in order to determine the radioactivity content. The highest contents of 125I-labeled L.q venom were found in the liver and kidney that were quickly excreted into the urinary tract. Trial to label irradiated (1.5 & 3 KGy L.q venom was unsuccessful due to its decomposition. For that reason the utilization of the labeled irradiated L.q venom is of no meaning. In immunodiffusion technique, both irradiated and native venoms exhibited prominent precipitin bands indicating high concentration of specific antibodies against polyvalent antivenin with venom. Furthermore, the effect of half the LD50 of native or irradiated (1.5 KGy L.q venom was studied on the activities of certain enzymes: ASAT, ALAT, LDH, CPK, CPK-MB, and the levels of total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol and the oxidative stress biomarkers (plasma MDA & blood GSH. Biochemical measurements showed that scorpion venom envenomation caused significant (p < 0.05 elevation in serum ASAT, ALAT, LDH, CPK as well as CPK-MB activities, blood GSH level while, caused significant (p < 0

  9. The in vivo pharmacokinetics study of anti-ProGRP(31-98) monoclonal antibody E-B5

    International Nuclear Information System (INIS)

    Objective: Progastrin-releasing peptide(31-98) (ProGRP(31-98) is a specific tumor marker in patients with small cell lung cancer (SCLC). E-B5 antibody against ProGRP(31-98) was produced by China Institute for Radiation Protection. The aim of this study was to explore the 131I labeling methods, stability, immunological activity and biological distribution pattern of E-B5 antibody against ProGRP(31-98). Methods: Chloramine-T method was used for 131I labeling E-B5 antibody. Labeling efficiency, radiochemical purity and stability were estimated by using paper chromatography method. Immunological activity of 131I-E-B5 was detected with cell conjugation assay. After healthy Kunming mice were injected with 131I-E-B5 antibody through tail veil, the biodistribution and pharmacokinetics of 131l-E-B5 antibody in healthy Kunming mice were studied. Continuous images of the nude mice beating SCLC were carried out at different time points after injection of 131I-E-B5 antibody. Continuous variables were expressed as x-bar ± s and compared by t-test with SPSS 13.0 software. Results: The labeling efficiency and radiochemical purity of 131I-E-B5were 90.8%, 99.28%, respectively. The radiochemical purity still maintained above 70% after incubation in water bath at 37 degree C for 24 h. After incubation with healthy serum for 24 h, the radiochemical purity still reached 68.1%. The immunobinding ratios were 71.6% and 33.2% for NCI-H446 cells and A549 cells respectively. The in vivo distribution and elimination of 131I-E-B5 antibody were consistent with a first-order and two-compartment model, t1/2α =0.2 h, t1/2β = 8.35 h. The metabolism of 131I-E-B5 antibody mainly depended on liver and kidney and with rapid elimination in blood. Conclusions: 131I-E-B5 antibody not only has high labeling efficiency and radiochemical purity, but also has good stability and keeps good immunological activity. 131I-E-B5 is a promising agent of radioimmunoimaging and radioimmunotherapy of SCLC. (authors

  10. Vasoactive intestinal peptide receptor scintigraphy in patients with pancreatic adenocarcinomas or neuroendocrine tumours

    International Nuclear Information System (INIS)

    Human adenocarcinomas of the gastroenteropancreatic system overexpress vasoactive intestinal peptide (VIP) receptors and therefore represent logical diagnostic targets for receptor scintigraphy. Using iodine-123 labelled VIP, the newly employed diagnostic procedure termed VIP receptor scintigraphy (VIP-RS) appears to detect tumour tissue, especially pancreatic metastatic tumours, in almost all cases. So far, however, only a single centre has demonstrated convincing positive results. The aim of this study was to compare the sensitivity and specificity of VIP-RS with those of computer tomography (CT) and transabdominal ultrasound in patients with extensive pancreatic metastatic adenocarcinomas and neuroendocrine tumours. VIP was radiolabelled with carrier-free 123I using the chloramine T-method and preparative high-performance liquid chromatography for purification. Patients with metastatic pancreatic (n=12) and colorectal (n=3) carcinomas (adenocarcinoma: n=13, neuroendocrine tumour: n=2) were studied by VIP-RS, CT, ultrasound and, in one case, also by radioligand receptor autoradiography. Carrier-free radioiodinated VIP of maximum specific radioactivity maintained a high biological activity as determined by cAMP formation in receptor-expressing tumour cell lines. Intravenous injection of 123I-VIP did not cause any side-effects. Biodistribution, determined over 24 h, was high in the lungs and low in abdominal organs. Although all patients had extensive metastatic disease as evidenced by CT and ultrasound, VIP-RS was unable to detect either primaries or metastases in these patients. Only in two patients could a significant uptake of radiolabel be detected in organs directly infiltrated by the primary. To exclude false-negative findings, tumour tissue in one patient with a large primary, undetectable by VIP-RS, was analysed by radioligand receptor autoradiography and shown to be receptor positive. Moreover, in vitro receptor determinations showed that pancreatic

  11. Radioiodine-labeling of salidroside and its biodistribution in mice

    International Nuclear Information System (INIS)

    To investigate the preparation of radioiodinated salidroside and its cell uptake in SH-SY5Y and its biodistribution in mice, salidroside was labeled with 131I using the chloramine-T method and the radiolabeled compound was characterized by polyamide TLC, in which the substratum of Vtrichoromethane:Vmethanol:Vacetone:Vwater=6:3:1:1 was used as the developing agent. The uptake of 131I-salidroside in human neuroblast cells (SH-SY5Y) and mammary cancer cells (MCF-7) was then measured and the biodistribution studies were carried out in KM mice. At different time (5, 10, 30, 60, 120, and 240 min) after radiopharmaceutical i.v. administration (1.85 MBq 131I-salidroside/mouse), the animals were sacrificed (n=5 animals for each time). Blood and the interested tissues samples were collected, washed, weighted and counted. The percent injected dose per gram (%ID/g) was calculated for each sample. The labeling yield of 131I-salidroside was 98% and its RCPs were 98.5%, 97.3% and 97.1% after 1, 4 and 20 days, respectively. In SH-SY5Y, 131I-salidroside uptake kept at a low level of around 0.035% from 0.5 to 4h, while in MCF-7 a slightly higher uptake of 0.1% was reached. Biodistribution in mice demonstrated that 131I-salidroside was metabolized mainly in liver and rapid elimination through kidney, in which the % ID/g were 7.71% and 11.31% at 5 min, 0.36% and 0.3% at 4h, respectively. Rapid clearance was also found in blood, 6.43% at 5 min and 0.11% at 4h. In heart, lung, spleen, muscle, bone, and intestines, there were little distributions. It is concluded that labeling yield of 131I-salidroside was high and the radioiodinated salidroside was stable, but its uptake in neuroblast was little. (authors)

  12. Improved iodine radiolabels for monoclonal antibody therapy.

    Science.gov (United States)

    Stein, Rhona; Govindan, Serengulam V; Mattes, M Jules; Chen, Susan; Reed, Linda; Newsome, Guy; McBride, Bill J; Griffiths, Gary L; Hansen, Hans J; Goldenberg, David M

    2003-01-01

    A major disadvantage of (131)iodine (I)-labeled monoclonal antibodies (MAbs) for radioimmunotherapy has been the rapid diffusion of iodotyrosine from target cells after internalization and catabolism of the radioiodinated MAbs. We recently reported that a radioiodinated, diethylenetriaminepentaacetic acid-appended peptide, designated immunomedics' residualizing peptide 1 (IMP-R1), was a residualizing iodine label that overcame many of the limitations that had impeded the development of residualizing iodine for clinical use. To determine the factors governing the therapeutic index of the labeled MAb, as well as the factors required for production of radioiodinated MAb in high yield and with high specific activity, variations in the peptide structure of IMP-R1 were evaluated. A series of radioiodinated, diethylenetriaminepentaacetic acid-appended peptide moieties (IMP-R1 through IMP-R8) that differed in overall hydrophilicity and charge were compared. Radioiodinations of the peptides followed by conjugations to disulfide-reduced RS7 (an anti-epithelial glycoprotein-1 MAb) furnished radioimmunoconjugates in good overall incorporations, with immunoreactivities comparable to that of directly radioiodinated RS7. Specific activities of up to 8 mCi/mg and yields > 80% have been achieved. In vitro processing experiments showed marked increases in radioiodine retention with all of the adducts; radioiodine retention at 45 h was up to 86% greater in cells than with directly iodinated RS7. Each of the (125)I-peptide-RS7 conjugates was compared with (131)I-RS7 (labeled by the chloramine-T method) in paired-label biodistribution studies in nude mice bearing human lung tumor xenografts. All of the residualizing substrates exhibited significantly enhanced retention in tumor in comparison to directly radioiodinated RS7, but the nontarget uptakes differed significantly among the residualizing labels. The best labels were IMP-R4 and IMP-R8, showing superior tumor-to-non-tumor ratios

  13. Biochemical and pharmacological studies of native and irradiated crotamine with gamma radiation of {sup 60}Co; Estudo bioquimico e farmacologico das crotaminas nativa e irradiada com radiacao gama de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Mitake, Malvina Boni

    2000-07-01

    Ionizing radiation can change the molecular structure and affect the biological properties of biomolecules. This has been employed to attenuate animal toxins. Crotamine is a strongly basic polypeptide from the South American rattlesnake venom, composed of 42 amino acid residues. It induces skeletal muscle spasms leading to a spastic paralysis of hind limbs in mice. The objective of this thesis was carry out biochemical and pharmacological studies of native and irradiated crotamine with {sup 60} Co. Crotamine was purified from Crotalus durissus terrificus venom by Sephadex G-100 gel filtration followed by ion exchange chromatography, using a Fast Performance Liquid Chromatography (FPLC) system. It was irradiated at 2 mg/ml in 0.15 M Na Cl with 2.0 kGy gamma radiation emitted by a {sup 60} Co source. The native and irradiated crotamine were evaluated by biochemical characterization, toxic activity (LD{sub 50} and biodistribution. The native and irradiated crotamine were labelled with 29.6 MBq of {sup 125} I using chloramine T method, and separated in a Sephadex G-50 column. Male Swiss mice (35{+-} 5 g), were injected i.p. with o.1 mL (2.4 x 10{sup 6} cpm/mouse) of {sup 125} I native crotamine or with 0.4 mL (1.3 x 10{sup 6} cpm/mouse) of {sup 125} I irradiated crotamine. At 0.08; 0.25; 0.5; 1; 2; 4; 8; 12 and 24 hours the animal were killed by ether inhalation. Blood, spleen, liver, kidneys, brain, lungs, heart, and skeletal muscle were collected in order to determine radioactivity content. The results showed that gamma radiation did not change the protein concentration, the electroforetic profile or the primary structure of the protein, although differences were shown by spectroscopic techniques. The gamma radiation diminished the toxicity of crotamine, but it did not abolish bioactivity. Biodistribution studies showed that native and irradiated crotamine have hepatic metabolism and renal elimination. The native and irradiated crotamine have affinity by skeletal

  14. Preparation of the radiopharmaceutical {sup 131}I-Anti-CD20 for the treatment of lymphomas; Preparacion del radiofarmaco {sup 131}I-Anti-CD20 para el tratamiento de linfomas

    Energy Technology Data Exchange (ETDEWEB)

    Pantoja H, I.E

    2004-07-01

    At the present time they are considered to the lymphomas like a problem of first magnitude since has happened it is necessary to be the fifth cancer cause in the world. Different treatments focused to the lymphoma like the chemotherapy and the radiotherapy, have been employees to counteract the No-Hodgkin lymphoma, without these they don't exclude the healthy tissue of the toxicity. It is for it that is taking a new direction with the employment of the directed radioimmunotherapy since this it allows to kill wicked cells selectively with radiation dose joined to the apoptosis and cytotoxicity induced by the own one bio molecule. The radioimmunotherapy with radiolabelled antibodies directed to the surface antigen CD20 represents a new modality for the treatment of No-Hodgkin lymphoma and potentially other illnesses. In this work the parameters of optimization are presented for the preparation, control of quality and evaluation of the stability in vitro and in vivo of the monoclonal antibody anti-CD20 labelled with {sup 131} I for the treatment of No-Hodgkin lymphoma. The anti-CD20 labelled by the chloramine-T method with high radiochemical purity (>98%), it is stable in solution for but of a half life of the radionuclide (8.04 days) The {sup 131} I-anti-CD20 doesn't present dehalogenation in vitro (human serum) during 24 h of incubation at 37 C. According to the tests carried out to establish the immunoreactivity, a percentage of union to cells was obtained (B lymphocytes) bigger to 30%. The biodistribution in mice balb/c one hour after their administration, it shows that there is not high reception in mucous neither kidneys, what indicates that the complex is stable in vivo. In conclusion, the radiopharmaceutical {sup 131} I-anti-CD20 was obtained in sterile injectable solution and free of pyrogens with a radiochemical purity bigger to 98% and a specific activity of 296 MBq. The radiolabelled molecule maintains its biological recognition for the receiving

  15. Experimental study of radiotargeting-therapy with small molecular polypeptide in nude mice bearing lung adenocarcinoma

    International Nuclear Information System (INIS)

    Background: Integrin signal transduction pathways provide an important basis for molecular targeting therapy of cancer in tumor growth, infiltration and transfer. Existing research data have shown that small molecular peptide labeled with radionuclide has good clinical application prospects, but the successful researches on lung cancer have not been reported so far. It is considered that the main reason is the lack of small molecule peptide for specific targeting lung cancer. Purpose: Based on the small molecular peptide cNGQGEQc for specifically identifying integrin α3 and β1 found previously, polypeptide cNGQGEQc is selected and radiolabelled with 131I. And the inhibitory effect of 131I-cNGQGEQc in nude mice bearing lung adenocarcinoma is observed. Methods: The coupling of cNGQGEQc and tyrosine was done in the processing of solid phase synthesis of small molecular peptide. Chloramine-T method was used for radiolabelling of cNGQGEQc with 131I. Twenty nude mice bearing NCI-H1975 were built and randomly divided into four groups with five mice in each group, including the group of 131I-cNGQGEQc, the group of 131I-cNAQAEQc, the group of 131I and the saline control group. The general condition was observed in nude mice bearing tumor after tail vein injection of corresponding drugs. And the tumor sizes after grafting were measured per 3 days in 30 days. The inhibitory rate of tumor in each group was calculated. Results: The labeling efficiencies of 131I-cNGQGEQc and 131I-cNAQAEQc were greater than 90% with the radiochemical purity of more than 95%, and 131I-cNGQGEQc had obvious inhibitory effect for transplantation tumor in nude mice bearing NCI-H1975 adenocarcinoma of lung. After a treatment for 30 days the tumor inhibitory rates were 60.93% for the group of 131I-cNGQGEQc, 11.63% for the group of 131I-cNAQAEQ and 10.70% for the group of 131I. Conclusion: 131I-cNGQGEQC has a good affinity and effective inhibit effect for the NCI-H1975 lung adenocarcinoma. Integrin is

  16. Comparison of [131I]-Tyr3-octreotate and [131I]DOTA-Tyr3-octreotate: the effect of DOTA on the pharmacokinetics and stability

    International Nuclear Information System (INIS)

    The introduction of radiolabeled somatostatin analogs for peptide receptor imaging and therapy of neuroendocrine cancer have become a primary focus of interest in nuclear medicine. In this work we studied the possibility of preparing radioiodinated octreotate derivatives, with high stability and favourable kinetic in vivo, because 131I-iodide is most frequently used in therapeutic nuclear medicine and aviable. We studied molar peptide to radionuclide ratio in order to obtain the mono-iodinated peptide (di-iodinated no longer binds to the somatostatin receptor). Like other radioiodinated proteins labeled on constituent tyrosine residues, it was important to study the possibility of dehalogenation in vivo. Despite DOTA chelating group was not necessary to the radioiodination procedure, we intended to evaluate the influence of the chelating group on the pharmacokinetic and the in vivo stability of the labeled peptide. 131I radiolabeling of Tyr3-octreotate and DOTA-Tyr3-octreotate was performed using Chloramine T method. A solution of 10 μg of peptide/40 μL of PBS (0.05M phosphate-buffered saline pH 7.5) was transferred to an Eppendorf cap. After addition of 10 μL (74 MBq) radioiodine and 5 μL of chloramine T solution (1mg/mL PBS), the cap was carefully stirred and the labeling reaction was allowed to proceed for 3 minutes at room temperature; 5 μL of sodium methabisulfite solution (2mg/mL PBS) was introduced as reducing agent. Radiochemical purity was determined by HPLC (Waters) using a RP C18 column (4.2 x 50 mm, 5 μm, Waters) with UV (230 nm) and radioactivity (Packard Canberra) detection, flow rate of 0.5 mL/minute with a linear gradient of 40-80% (v/v) methanol in 50 mM sodium acetate buffer (pH 5.5) for 20 minutes, maintained for another 25 minutes. Free radioiodine was also determined by horizontal zone electrophoresis (Amershan Pharmacia) on Whatman 1 paper, 0.05M barbital buffer, pH 8.6, 300V, 40 minutes. The stability of the compounds were evaluated

  17. Iodine labelled diethylstilbestrol (DES) of high specific activity: A potential radiopharmaceutical for therapy of estrogen receptorpositive tumours and their metastases?

    International Nuclear Information System (INIS)

    After binding to the estrogen receptor (ER) estrogens are localized very close to the DNA. Therefore, radioactively labelled estrogens, especially in connection with Auger-electron emitters which have only a very short range (1-10 nm) of radiation, are excellent candidates to achieve high specific cytotoxicity, in combination with a low degree of side effects. Diethylstilbestrol (3,4-Di-(4'-hydroxyphenyl)-hexene-3) is a well-known, synthetic, non-steroidal estrogen, which has a higher affinity to the estrogen receptor than the natural hormone estradiol itself. The idea to use iodine labelled DES for imaging of ER positive tumours is not new. Several working groups successfully tried to label DES with different methods and investigated the diagnostic usefulness of the product. Most attempts for labelling with radioiodine have been made with a water soluble derivate of DES, the tetra-sodium salt of diethylstilbestrol-diphosphate (DES-2P). Former labelling methods had some disadvantages: low yield (20-30%), low specific activity (0.7 - 2.9 GBq/mmol), bad reproducibility, and time consuming procedures. Presumably, the low specific activity was the reason for the unsatisfying biodistribution data observed with this labelled compounds. In the present work a fast and simple labelling and purification method for *I-DES was used and its binding affinity for ER was determined. For testing its cytotoxic effects on MCF-7 mamma carcinoma cells different iodine isotopes bound to DES or in form of iodide were compared with regard to apoptosis, necrosis, and viability. Last but not least first animal experiments with tumour bearing mice were carried out. DES was iodinated by Chloramine T in methanolic solution. Purification and quality control was carried out with reversed phase HPLC (column: Column: Hypersil ODS, 250 x 4 mm, 10 Ym, Eluent A: Methanol G, Eluent B: Water G, Gradient: 20% A to 70% A within 5 min, Flow: 1 ml/min, UV-Detection: 254 nm). The dissociation constants for

  18. Administering of I-125 preparation from blood of tortoise into organs of rats with experimental ovarian carcinoma

    International Nuclear Information System (INIS)

    Full text: Complexes of substances of the peptide nature, received mainly from lymphoid bodies that normalize immune processes, are offered. The preparation 'Tortesin' can be related to this group. Tortesin is a drug isolated from the blood cells of the Central Asian tortoise, an animal with a unique radioresistance (LD50 = 100 Gy). During a short spring the tissues of tortoises produce biogenetic stimulators that can positively affect the organisms of irradiated animals. Tortesin acts by stimulating haemo- and immunopoietic systems and aids in recovery from radiation exposure. Thus, at animals treated with Tortesin, DNA and RNA synthesis in the bone marrow was enhanced, both antibody forming cells number and spleenic size increased, and haemopoietic parameters normalized. The survival rate also increased. That is why the determination of the point of initial application of the preparation is an important scientific objective. The research with the use of 125I was carried out for this purpose. The labeling was conducted via reaction with chloramine T. The preparation 125I issued by 'Radiopreparat' (Tashkent) was used. After the purification by chromatography the activity of 1000 impulse/min by 1 μg of protein was got. The experiment was carried out in the Center of oncology and radiology Republic of Uzbekistan. The including of the marker was being determined in young rats at the age of 1 month with an experimental ovarian carcinoma in 15 min, 1 hour and 1 day after the injection. The preparation was injected into the tail vein. The following 22 organs were examined: blood, ascitic fluid with cells, ascitic fluid without cells, tumor, liver, spleen, stomach, bowels, lungs, heart, testicles, kidneys, cerebral, marrow, thymus, fat, muscles, skin, thyroid gland, thigh-bone, tail, excrements. The results can be classified into three groups. The first group of organs (heart, cerebral, cells from tumor, thigh-bone, marrow, thyroid gland, thymus,) do not include the

  19. Utilization of N-X bonds in the synthesis of N-heterocycles.

    Science.gov (United States)

    Minakata, Satoshi

    2009-08-18

    Nitrogen-containing heterocycles--such as aziridines, pyrrolidines, piperidines, and oxazolines--frequently show up as substructures in natural products. In addition, some of these species show potent biological activities. Therefore, researchers would like to develop practical and convenient methods for constructing these heterocycles. Among the available methods, the transfer of N(1) units to organic molecules, especially olefins, is a versatile method for the synthesis of N-heterocycles. This Account reviews some of our recent work on the synthesis of N-heterocycles using the N-X bond. A nitrogen-halogen bond bearing an electron-withdrawing group on the nitrogen can be converted to a halonium ion. In the presence of C-C double bonds, these species produce three-membered cyclic halonium intermediates, which can be strong electrophiles and can produce stereocontrolled products. N-Halosuccinimides are representative sources of halonium ions, and the nitrogen of succinimide is rarely used in organic synthesis. If the nitrogen could act as a nucleophile, after releasing halonium ions to C-C double bonds, we expect great advances would be possible in the stereoselective functionalization of olefins. We chose N-chloro-N-sodio-p-toluenesulfonamide (chloramine-T, CT), an inexpensive and commercially available reagent, as our desired reactant. In the presence of a catalytic amount of CuCl or I(2) and AgNO(3), we achieved the direct aziridination of olefins with CT. The reaction catalyzed by I(2) could be carried out in water or silica-water as a green process. The reaction of iodoolefins with CT gave pyrrolidine derivatives under extremely mild conditions with complete stereoselectivity. We also extended the utility of the N-chloro-N-metallo reagent, which is often unstable and difficult to work with. Although CT does not react with electron-deficient olefins without a metal catalyst or an additive, we found that N-chloro-N-sodiocarbamates react with electron

  20. Radiolabelled DOTA-TATE: Its evaluation for targeted radiotherapy

    International Nuclear Information System (INIS)

    The development of a radiopharmaceutical for cancer therapy based on a somatostatin analog peptide DOTATATE (DOTA-D-phe-cys-tyr-D-trp-lys-thr-cys-thr) labelled with I-125 was done and the biological properties were investigated. Labelling of the DOTA-TATE was achieved by oxidation of iodide with Chloramine-T. Purification was done by C18 separation cartridge using ethanol as the eluent and further reverse-phase chromatography (HPLC) on the eluate to increase specific activity. Stability of the labelled peptide at different time intervals as well as storing conditions was evaluated by RPHPLC and by chromatography in ITLC-SG or Whatman 3MM using different mobile phases: 2-butanone (MEK); NaCl 0.9%; EtOH-HCl 0.01N 90:10 and butanol:acetic:H O (4:1:5) (2). Also, electrophoresis was 2 done on Whatman 1 with Tris buffer, (pH 7.5, 200V, 80mA, 45 min). Biological behaviour of I-125 DOTA-TATE was evaluated through interaction with somatostatin receptors extracted from rat cortex membranes as well as from AR4- 2J cell membranes. In vitro binding of the peptide to viable AR4-2J was evaluated through internalization studies. The labelling yield obtained was higher than 95%. HPLC profile revealed that two radiochemical species were present having retention times of 23.5 and 25.0 min, while the unlabelled peptide eluted at 21.0 min. I-125 DOTATATE was obtained with very high yield even prior purification. The two radiochemical species evidenced by RP-HPLC could be interpreted as mono and diiodinated radio-conjugate species. Their retention times are slightly higher than the intact unlabelled peptide allowing the preparation of a labelled molecule with high specific activity. Stability of the radio-conjugate (at -4 deg. C and -80 deg. C) was determined over a period of more than 8 days. Maximum binding capacity (MBC) was found to be 23% for the species eluted at 25 min. Also MBC was lower for receptors obtained from AR 42J cells. 50% Inhibition dose was 9μg/mL (CV 20%). The

  1. Synthesis and biodistribution study of 3-iodo-4-hydroxyphenyl-cysteamine for detection of malignant melanoma based on specific enzyme of melanin formation

    International Nuclear Information System (INIS)

    Purpose: The aim of our study is to develop a new radiopharmaceutical labeled with radioiodine for detection and therapy of tumors, which have affinity to a characteristic metabolism in tumor. 3-Iodo-4-hydroxyphenyl-L-cysteine (I- L-PC), which we have reported previously, was found to have an interaction for tyrosinase, an essential and rate-limiting enzyme to melanin biosynthesis. In this study, considering higher affinity for tyrosinase, we synthesized 3-iodo-4-hydroxyphenylcysteamine (I-PCA) that was an amine derivative of I-L-PC and examined biodistribution study in melanoma-bearing mice. Method/Materials: 4-Hydroxyphenylcysteamine (4-PCA) was synthesized and radioiodinated in our laboratory. Synthesis of 4-PCA was confirmed by 1H-NMR, mass spectrometry and elemental analysis. 125I-PCA was prepared by conventional chloramine-T method under a no-carrier added condition. 125I-PCA was purified by Sep-Pak-C-18 cartridge and the labeling efficiency and radiochemical purity were examined by TLC analysis. Biodistribution study of I-PCA was performed using B16 melanoma-bearing C57BL6 mice. The radioactivities of each organ were measured and % injected dose / g wet tissue was determined. Moreover, the tumor-to-blood ratio (T/B ratio) and tumor-to-muscle ratios (T/M ratio) of 125I-PCA were also evaluated and were compared with 125I-L-PC, 67Ga-citrate, 125I-L-AMT and 123I-MIBG. Results: Radiosynthesis of 125I-PCA was carried out conveniently and efficiently within only 15 min. A labeling efficiency of more than 73 % resulted in the labeling of 4-PCA to 125I-PCA. After the simple Sep-Pak purification, no-carrier added 125I-PCA with radiochemical purity greater than 90 % was obtained. The biodistribution of 125I-PCA showed rapid blood clearance, renal excretion and low accumulation in normal tissue, while increase of accumulation in the tumor for 30 min. As a consequence, T/B ratio reached approximately 1.6 ± 0.3 and T/M ratio increased up to 8.7 ± 3.2 at 60 min after

  2. Comparative biodistribution profile of [131I]VIP and [131I]VIP10-28

    Directory of Open Access Journals (Sweden)

    Maria Tereza Colturato

    2005-10-01

    Full Text Available Various tumor cells express significantly higher amounts of VIP receptors (VIPR that provided the basis for the clinical use of radiolabeled VIP for the in vivo localization of tumors. This work studied the labeling of VIP and VIP10-28 with iodine-131 to compare the biological distribution of the labeled compounds in Nuce mice and the affinity for tumor cells. Both VIP and VIP10-28 peptides contain two tyrosine residues, in positions 10 and 22, that are theoretically equally susceptible to radioiodination employing oxidative electrophilic substitution using oxidizing agents like Chloramine T. Radiochemical purity of the reaction mixture was determined by electrophoresis and HPLC. The VIP peptide and the fragment were labeled with radioiodine with good radiochemical yield (above 96%. Suitable, but important differences can be observed in biological distribution studies. Comparatively, blood clearance was faster for labeled VIP and perhaps because of this, the uptake in tumor was lower, especially during the first hour. These differences observed in the biological distribution of the compounds can be related to the lipophilicity of the labeled compounds.Várias células tumorais expressam significantemente uma alta quantidade de receptores VIP (VIPR que determinam a base para o uso clínico de VIP radiomarcado para localização de tumores in vivo. Foi estudado neste trabalho a marcação do VIP e do fragmento VIP10-28 com iodo-131 comparando a distribuição biológica dos compostos marcados em camundongos Nude e sua afinidade pelas células tumorais. Ambos os peptídeos, VIP e VIP10-28. contém dois resíduos de tirosina nas posições 10 e 22, que teoricamente são igualmente susceptíveis pela substituição eletrofílica oxidativa do radioiodo utilizando Cloramina T como agente oxidante. A pureza radioquímica da mistura de reação foi determinada por eletroforese e cromatografia líquida de alta eficiência (CLAE. O VIP e fragmento foram

  3. I-131 rituximab (chimeric anti Cd 20 mab) radioimmunotherapy of non-Hodgkins lymphoma

    International Nuclear Information System (INIS)

    Full text: Commercially available anti-CD 20 monoclonal antibody, rituximab (MabThera) may be efficiently radioiodinated with 131I using standard Chloramine-T methodology in a hospital radiopharmacy, under appropriate regulatory authority approvals. Multicentre clinical trials of 131I-rituximab radioimmunotherapy have been performed in patients with relapsed or refractory low grade non-Hodgkins lymphoma with therapeutically effective administered activities being determined on the basis of individualised prospective patient dosimetry. A non-myeloablative regimen of 131I-radioimmunotherapy predicated upon a maximum prescribed dose of 0.75 Gy to whole body has been used to minimise myelotoxicity in patients undergoing radioimmunotherapy, even when they have been heavily pre-treated with chemotherapy and/or there is tumour infiltration of bone marrow greater than 25%. Provided that baseline leucocytes exceeded an absolute neutrophil count of 1.5 x 109/L and platelets > 100 x 109 /L, the incidence of grade IV haematological toxicity was 16% for neutrophils and 4 % for platelets which was self-limited. The red marrow radiation absorbed dose in selected patients receiving 131I activities estimated to deliver 0.75 Gy to whole body was calculated to be less than 2 Gy using Monte Carlo methodology on post therapy CT/SPECT imaging. Predictive dosimetry was performed by serial whole body imaging following IV administration of a standard 200 MBq 131I-rituximab tracer and determination of individual pharmacokinetics of the radiolabelled antibody in each patient. A standard dose of 375 mg/m2 unlabelled rituximab (MabThera) was administered IV immediately prior to the tracer and therapy doses of 131I-rituximab to minimise nonspecific uptake of the radiolabelled antibody and to optimise the tumour to background activity. The administration of a standard course of 4 cycles of cold rituximab (MabThera) in association with the prescribed maximum activity of 131I-rituximab constitutes

  4. Labelling and biological valuation of anti-CD-20 for treatment of non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Full text: Anti-CD20 monoclonal chimeric humanized murine antibodies (Rituximab), have been successfully applied for the treatment of Non Hodgkin's Lymphoma. However, upon labelling of the mab-CD20 with β-emitters as 90Y, the therapeutic efficacy has significantly increased due to radiological effects of ionizing radiation. Our objective was to develop reliable and efficient methods for labelling anti-CD20 with β-emitters of therapeutic interest and simple and rugged quality control methods to evaluate radiochemical purity, biological performance and immunoreactivity assessment. 131I and 188Re have been used for the labelling of anti-CD20 as two attractive alternatives due to decay properties and availability (188Re: Eβmax: 2.2MeV, Eγ 0,155MeV, T=17h, generator produced; 131I: Eβmax: 0,63MeV, Eγ 0,364MeV, T=8d). Labelling of anti-CD20 was optimized following the oxidation procedure of chloramine-T in the case of 131I and the synthesis of 188Re(IV) complex with the previously reduced monoclonal antibody. Quality control of the species obtained were done by physicochemical methods, including ITLC-SG and HPLC, non specific protein precipitation, biological distribution in normal mice and immunoreactivity studies with membrane antigens extracted from isolated leucocytes. 131I- (more than 3.7 GBq/mL) was introduced on tyrosyl residues of the protein chain by adding 28 MBq to 20μg of anti CD20 (Mab Thera, 10mg/mL) at pH 7.4 and 1.3μg of Choramine-T. Purification was done by gel-permeation with sephadex G-25 (PD-10, Pharmacia). For labelling with 188Re, anti CD20 was first reduced by incubation with 2- mercaptoethanol and purified over a PD10 column. Fractions of reduced antibody were pooled and formulated as kit for instant labelling. Each kit contained 1mg anti-CD20; 82.8mg of sodium tartrate; 1.67 mg of stannous fluoride and 0.25 mg gentisic acid. For the labelling, sodium perrhenate (1.5-1.9 GBq) was acidified, added to the kit and then incubated for 1 hour at

  5. Preclinical study of radioiodinated glucose-Tyr3-octreotate: Comparison with 111In-DOTA-Tyr3-octreotate

    International Nuclear Information System (INIS)

    Full text: Targeted radionuclide imaging and treatment are based upon the interaction of radioligands with receptors in the target tissue (namely high density receptor specific tumours). As receptors for somatostatin (mainly somatostatin receptor subtype-2 /sstr2/) are over-expressed in several human tumours of endocrine origin, a number of radiolabeled somatostatin analogs have been recently introduced as the vectors for targeted imaging and therapy; commercially available 111In-DTPA-octreotide being a gold standard in this field. Several publications demonstrate that a substitution of Tyr instead of Phe in the peptide position 3 and oxidation of carboxyl end of octreotide significantly increased the affinity of the peptide to sstr2. More recently it has been shown that NH2-terminal carbohydration leads to a further improvement of the peptide receptor affinity and its retention in the tumour. In this study we present preclinical analysis of distribution profile and elimination pathways of radioiodinated glucose-Tyr3-octreotate (125I-gluc-TOCA) in comparison with that of another promising targeted radiopharmaceutical, namely 111In-DOTA-Tyr3-octreotate (111In- DOTA-TOCA). Gluc-TOCA was radioiodinated using chloramine-T method. For radiolabeling of DOTA-TOCA with radiometal, to 200 μl of 0.4 M acetate buffer with 0.24 M gentisic acid pH 5, 10μl of peptide solution in 0.1% TFA (1mg/ml) were added together with 0.5-1 mCi of 111InCl3 in 0.04 M HCl. Reaction mixture was heated 25 minutes to 90-95 deg. C. Pharmacokinetic studies were performed on male Wistar rats. Results confirmed that specific internalization of 125I-gluc-TOCA by sstr2 - expressing AR423 rat pancreatic carcinoma cells in vitro was about twice of that for 111In-DOTA-TOCA. In rats, 125I-gluc-TOCA exhibited prolonged plasma clearance in comparison with the other peptide. Slower decrease of plasma radioactivity after 125I-gluc-TOCA was due to its higher lipophilicity and thus higher plasma protein binding

  6. Effect of cardiac muscle collagen and actin on myocardiopathological change of diabetes mellitus%心肌胶原蛋白和肌动蛋白对糖尿病心肌病变的研究

    Institute of Scientific and Technical Information of China (English)

    吴伟; 张锦; 邱阳

    2005-01-01

    目的研究糖尿病大鼠不同病程心肌胶原蛋白和骨架蛋白含量的变化,阐明两者对糖尿病心肌病变发生的作用.方法制造糖尿病大鼠心肌模型随机分组.氯胺T法测定羟脯氨酸含量,代表心肌胶原总含量.心肌免疫组织化学染色测定心肌胶原蛋白(Collagen Ⅰ、Collagen Ⅲ)和心肌型α肌动蛋白(α-actin)及转化生长因子β1(TGF-β1)平均积分光密度(IOD).心肌病理改变的光镜和透射电镜观察.结果糖尿病痛程6个月组心肌胶原总含量明显高于病程3个月以内组(P<0.01).病程3个月之后Ⅰ型胶原蛋白表达伴随TGF-β1的表达开始较健康鼠明显增加(P<0.01).α-actin蛋白表达较健康鼠明显减少(P<O.01).糖尿病鼠心肌横切面可见粗大胶原纤维相互连接成网状,排列紊乱,分布不匀.心肌细胞心肌型α-actin蛋白分布不均匀,着色呈浅黄色,心肌纵切面可见α-actin蛋白表达主要分布于心肌肌膜处.病程3个月后大鼠心肌细胞核皱缩,线粒体肿胀、模糊,闰盘不连续,α-actin蛋白表达明显减少,有糖原沉积现象.结论Ⅰ型心肌胶原蛋白呈现持续性增加是糖尿病鼠心肌纤维化的主要原因.心肌细胞核皱缩,线粒体肿胀、模糊,闰盘不连续,糖原沉积和心肌型actin表达减少是糖尿病心肌病病理基础.%[Objective] To investigate the content changes of myocardial collagenprotein and actin at different stages of diabetes mellitus(DM) rats. So as to illustrate that they play a role in myocardial changes of DM. [Methods] Cardiac muscle model of DM rats was grouped randomly. The hydroxy proline contents were measured with the chloramine T method. The type Ⅰ collagen, type Ⅲ collagen,transforming factor beta1 (TGF-beta1) and cardiactype α-actin were determined by myocardial immunehistochemical stain. Myocardiopathological change were observed with light microscope and transmission electron microscope. [Results] The collagen contents

  7. DOTA-TATE alternative labellings with halogens and radiometals

    International Nuclear Information System (INIS)

    Full text: DOTA-D-phe-cys-tyr-D-trp-lys-thr-cys-thr (DOTA-TATE), a somatostatin analog with high affinity for somatostatin receptors expressed in cancer of neuroendocrine origin, may be labeled with different beta radionuclides for its use in targeted radiotherapy. This allows the obtanting of products with particular chemical, radiochemical and biological properties, which interact in specific way with cells that express somatostatin receptors. In this study the labelling of DOTA-TATE with 125I, 131I and 177Lu and their biological properties were investigated, with the aim of potential application as a tumour seeking agents. Radioiodine was introduced on the tyrosyl residue of the DOTA-TATE by oxidation of iodide with chloramine-T. The labeled peptide was isolated from the reaction mixture by sep-pak purification and/or by RP-HPLC. Lutetium-177 was introduced in the peptide via the DOTA ring. To 7,2μg of DOTA-TATE 1mg/mL, 2μL 177LuCl3 (7.2 mCi) and 7.2 μL of gentisic acid in CH3COONa 0.4M were added. The mixture was incubated 30 minutes at 100 deg. C. Purification by RP-HPLC was conducted on a C18 column eluted with a linear gradient from 10% to 40% B in 30 min (A: 0.1% TFA in water and B: 0.1% TFA in acetonitrile). Fractions containing the labeled peptide were pooled and most of the solvent removed by evaporation and re-suspended in 1 mL of saline. For the control of 131I-DOTA-TATE, different gradients were used in order to optimize the separation. In the case of 177Lu-DOTA-TATE analysis, gradient was from 5 to 95% B in 15 minutes. Stability at different time intervals was evaluated by RP-HPLC and by chromatography in ITLC-SG or Whatman 3MM using different mobile phases: 2-butanone (MEK); NaCl 0.9%; EtOH-HCl 0.01N 90:10 and butanol:acetic:H2O (4:1:5) for radioidinated peptides. For 177Lu-DOTA-TATE, the chromatographic systems were: CH3COONH4 10%/MeOH (30:70), BuOH-CH3COOH-H2O (5:2:1), TFA 0,1% in ACN- H2O (1:1) and Sodium citrate 0.1M, pH:5 in Whatman 3MM (Rf

  8. 益气养阴、活血化瘀中药对糖尿病大鼠脂代谢紊乱及蛋白质非酶糖基化的影响%Effect of Chinese herb for benefiting qi, nourishing yin, activating blood circulation and resolving stasis on lipid metabolic disturbance and protein nonenzyme glycosylation in diabetic rats

    Institute of Scientific and Technical Information of China (English)

    戴红

    2005-01-01

    administered once every day in above 6 groups,and the treating course was 8 weeks. ③ Before treatment, on the 3rd, 6th and 8th weeks after treatment, fasting blood sugar was tested with One Touch Ⅱ tester. 8 weeks later, automatic biochemistry analyzer was used to assay triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDLC) and high-density lipoprotein cholesterol (HDLC). Thoracic aorta was collected swiftly and chloramine-T method was used to assay hydroxyproline content in the extract from aorta. Hydroxyproline content ×7.14=collagen content. Fluorescence spectrometer was used to assay the fluorescence degree of AGEs in collagen extract. ④ t test was applied for difference comparison of measurement data.MAIN OUTCOME MEASURES: ① Comparison of fasting blood sugar before and after treatment in each group. ② Comparison of blood lipid,collagen content and fluorescence degree of collagen-protein AGEs in thoracic aorta in 8 weeks after treatment in each group.RESULTS: At the end of experiment, 8, 4, 2, 2 and 3 rats were died in model group, insulin group, HXY low, middle and high-dose groups respectively, due to which, 12, 8, 11, 13, 13 and 12 rats entered result analysis in various groups respectively. ① Fasting blood sugar: Before treatment, it was higher remarkably in model and various treating groups compared with normal control (P < 0.01) and 8 weeks after treatment, it was lower remarkably in insulin group and various HXY groups compared with model group and before treatment (P < 0.01). ② Levels of TC, TG, LDLC in serum: Those in insulin and model groups were higher remarkably than normal control (P < 0.05-0.01). Those in insulin group and various HXY groups were lower remarkably than normal group (P < 0.05-0.01). ③ Level of HDLC: It was lower remarkably in insulin group and model group compared with normal control (P < 0.05-0.01), it was higher remarkably in HXY low and middle-dose groups compared with model group (P