Radiochemical stability of radiopharmaceutical preparations

International Nuclear Information System (INIS)

Martins, Patricia de A.; Silva, Jose L. da; Ramos, Marcelo P.S.; Oliveira, Ideli M. de; Felgueiras, Carlos F.; Herrerias, Rosana; Zapparoli Junior, Carlos L.; Mengatti, Jair; Fukumori, Neuza T.O.; Matsuda, Margareth M.N.

2011-01-01

The 'in vitro' stability studies of the radiopharmaceutical preparations are an essential requirement for routine practice in nuclear medicine and are an important parameter for evaluating the quality, safety and efficacy required for the sanitary registration of pharmaceutical products. Several countries have published guidelines for the evaluation of pharmaceutical stability. In Brazil, the stability studies should be conducted according to the Guide for Conducting Stability Studies published in the Resolution-RE n. 1, of 29th July 2005. There are also for radiopharmaceutical products, two specific resolutions: RDC-63 regulates the Good Manufacturing Practices for Radiopharmaceuticals and RDC-64 provides the Registration of Radiopharmaceuticals, both published on the 18th December 2009. The radiopharmaceutical stability is defined as the time during which the radioisotope can be safely used for the intended purpose. The radiochemical stability can be affected by a variety of factors, including storage temperature, amount of radioactivity, radioactive concentration, presence or absence of antioxidants or other stabilizing agents. The radiochemical stability studies must be established under controlled conditions determined by the effective use of the product. The aim of this work was to evaluate the radiochemical stability of labeled molecules with 131 I, 123 I, 153 Sm, 18 F, 51 Cr, 177 Lu and 111 In as well as 67 Ga and 201 Tl radiopharmaceuticals. Radiochemical purity was evaluated after production and in the validity period, with the maximum activity and in the recommended storage conditions. The analyses were carried out by thin-layer silica gel plate, paper chromatography and gel chromatography. The experimental results showed to be in accordance with the specified limits for all the analysed products. (author)

Advanced glycation end product (AGE) modified proteins in tears of diabetic patients.

Science.gov (United States)

Zhao, Zhenjun; Liu, Jingfang; Shi, Bingyin; He, Shuixiang; Yao, Xiaoli; Willcox, Mark D P

2010-08-11

High glucose level in diabetic patients may lead to advanced glycation end product (AGE) modified proteins. This study investigated AGE modified proteins in tears and compared their levels in diabetic patients (DM) with non-diabetic controls (CTL). Basal tears were collected from DM with (DR) or without (DNR) retinopathy and CTL. Total AGE modified proteins were detected quantitatively by a dot immunobinding assay. The AGE modified proteins were separated in 1D- and 2D-SDS gels and detected by western-blotting. The individual AGE modified proteins were also compared between groups using densitometry. Compared with the CTL group, tear concentrations of AGE modified proteins were significantly elevated in DR and DNR groups. The concentration of AGE modified proteins in diabetic tears were positively correlated with AGE modified hemoglobin (HbA1c) and postprandial blood glucose level (PBG). Western blotting of AGE modified proteins from 1D-SDS gels showed several bands, the major one at around 60 kDa. The intensities of AGE modified protein bands were higher in DM tears than in CTL tears. Western blotting from 2D-SDS gels showed a strongly stained horizontal strip, which corresponded to the major band in 1D-SDS gels. Most of the other AGE modified protein species were within molecular weight of 30-60 kDa, PI 5.2-7.0. Densitometry analysis demonstrated several AGE modified proteins were elevated in DR or DNR tears. Total and some individual AGE modified proteins were elevated in DM tears. AGE modified proteins in tears may be used as biomarkers to diagnose diabetes and/or diabetic retinopathy.

Radiochemical Solar Neutrino Experiments - Successful and Otherwise

International Nuclear Information System (INIS)

Hahn, R.L.

2008-01-01

Over the years, several different radiochemical systems have been proposed as solar neutrino detectors. Of these, two achieved operating status and obtained important results that helped to define the current field of neutrino physics: the first solar-neutrino experiment, the Chlorine Detector ( 37 Cl) that was developed by chemist Raymond Davis and colleagues at the Homestake Mine, and the subsequent Gallium ( 71 Ga) Detectors that were operated by (a) the SAGE collaboration at the Baksan Laboratory and (b) the GALLEX/GNO collaborations at the Gran Sasso National Laboratory. These experiments have been extensively discussed in the literature and in many previous International Neutrino Conferences. In this paper, I present important updates to the results from SAGE and GALLEX/GNO. I also review the principles of the radiochemical detectors and briefly describe several different detectors that have been proposed. In light of the well-known successes that have been subsequently obtained by real-time neutrino detectors such as Kamiokande, Super-Kamiokande, SNO, and KamLAND, I do not anticipate that any new radiochemical neutrino detectors will be built. At present, only SAGE is still operating; the Chlorine and GNO radiochemical detectors have been decommissioned and dismantled

Radiochemical solar neutrino experiments, 'successful and otherwise'

International Nuclear Information System (INIS)

Hahn, Richard L

2008-01-01

Over the years, several different radiochemical systems have been proposed as solar neutrino detectors. Of these, two achieved operating status and obtained important results that helped to define the current field of neutrino physics: the first solar-neutrino experiment, the Chlorine Detector ( 37 Cl) that was developed by chemist Raymond Davis and colleagues at the Homestake Mine, and the subsequent Gallium ( 71 Ga) Detectors that were operated by (a) the SAGE collaboration at the Baksan Laboratory and (b) the GALLEX/GNO collaborations at the Gran Sasso National Laboratory. These experiments have been extensively discussed in the literature and in many previous International Neutrino Conferences. In this paper, I present important updates to the results from SAGE and GALLEX/GNO. I also review the principles of the radiochemical detectors and briefly describe several different detectors that have been proposed. In light of the well-known successes that have been subsequently obtained by real-time neutrino detectors such as Kamiokande, Super-Kamiokande, SNO, and KamLAND, I do not anticipate that any new radiochemical neutrino detectors will be built. At present, only SAGE is still operating; the Chlorine and GNO radiochemical detectors have been decommissioned and dismantled.

Adhesives from modified soy protein

Science.gov (United States)

Sun, Susan [Manhattan, KS; Wang, Donghai [Manhattan, KS; Zhong, Zhikai [Manhattan, KS; Yang, Guang [Shanghai, CN

2008-08-26

The present invention provides useful adhesive compositions having similar adhesive properties to conventional UF and PPF resins. The compositions generally include a protein portion and modifying ingredient portion selected from the group consisting of carboxyl-containing compounds, aldehyde-containing compounds, epoxy group-containing compounds, and mixtures thereof. The composition is preferably prepared at a pH level at or near the isoelectric point of the protein. In other preferred forms, the adhesive composition includes a protein portion and a carboxyl-containing group portion.

Radiochemicals

International Nuclear Information System (INIS)

1980-01-01

In this catalogue those radioactive chemicals for research are listed which are produced by the Radiochemical Centre Amersham and our laboratories at Brunswick. The dates given for each product can understandably only be limited within the framework of such a catalogue. Additional dates and references to application technique can be obtained from us any time. Our programme is continually updated by new products. If a compound not listed in the catalogue should be required we ask for inquiry. Our working team for special syntheses will try to produce it according to our possibilities and our requirements. (orig.) [de

Evolution and applications of radiochemical procedures. From Marie Curie to Darleane Hoffman

International Nuclear Information System (INIS)

Contis, E. T.; Rengan, K.

1996-01-01

Marie Curie carried out the first radiochemical separations which eventually lead to the discovery of polonium and radium, two new elements. Nearly a century later Darleane Hoffman and her collaborators are devising new radiochemical separation procedures for studying the chemical properties of newly discovered transactinide elements. Safety requirements as well as changes necessitated by fast decaying radionuclides have transformed the nature of radiochemical separations. Further, applications in a wide variety of areas such as analysis of trace elements in food to radioimmunoassay have broadened the use of radiochemical separations. Examples of some early, historically important, radiochemical separations are described in this article. In addition, recent trends in the use of radiochemical separations in neutron activation analysis, in dating applications, in fission product studies and in the study of transactinide elements are briefly described with specific examples. (author). 52 refs

Modified Protein Improves Vitiligo Symptoms in Mice

Science.gov (United States)

... Vitiligo Symptoms in Mice Spotlight on Research Modified Protein Improves Vitiligo Symptoms in Mice By Colleen Labbe, ... D., Ph.D., Rush University. Altering a key protein involved in the development of vitiligo may protect ...

Radioactive preparations. Determination of radiochemical purity by thin-layer chromatography

International Nuclear Information System (INIS)

1986-01-01

The standard sets the data which must be attached to every sample, and the equipment, chemicals and auxiliary substances used in the determination of radiochemical purity of substances by chromatography. Described are preparation of the sample, the procedure of sample deposition, the development, drying and detection of the radioactive preparation. The qualitative and quantitative assessment of the radiochromatogram is described as are the calculation of radiochemical purity and the determination of the reproducibility of measurement of radiochemical purity of radioactive preparations. (E.S.)

Radiochemical analysis of phosphorus in milk samples

International Nuclear Information System (INIS)

Oliveira, R.M. de; Cunha, I.I.L.

1991-01-01

The determination of phosphorus in milk samples by thermal neutron activation analysis employing radiochemical separation is described. The radiochemical separation consists of the simultaneous irradiation of samples and standards, dissolution of the milk samples in a perchloric acid and nitric acid mixture, addition of zinc hold-back carrier, precipitation of phosphorus as ammonium phospho molybdate (A.M.P.) and sample counting in a Geiger-Mueller detector. The analysis sources of error were studied and the established method was applied to phosphorus analyses in commercial milk samples. (author)

Aspects of 6-[18F]fluoro-L-DOPA preparation: precursor synthesis, preparative HPLC purification and determination of radiochemical purity

International Nuclear Information System (INIS)

Fuechtner, F.; Angelberger, P.; Kvaternik, H.; Hammerschmidt, F.; Simovc, B. Peric; Steinbach, J.

2002-01-01

A modified method for the synthesis of the intermediate product N-Boc-3,4-di(Boc-O)-6-iodo-L-phenylalanine ethyl ester of the [ 18 F]FDOPA precursor preparation was developed. With the application of bis-(trifluoroacetoxy)-iodobenzene for the iodination step with elemental iodine the yield of the intermediate can be increased from 12% to 50-60%. By replacing silica-gel-based RP HPLC column by a polymer-based column for semi-preparative purification of [ 18 F]FDOPA from the reaction mixture the radiochemical purity of the final product can be increased up to >99%. For the determination of the radiochemical impurity [ 18 F]fluoride a HPLC method using a column with polymer-based RP material was introduced

Instrumentation for chemical and radiochemical monitoring in nuclear power plants

International Nuclear Information System (INIS)

Nordmann, F.; Ballard, G.

2009-01-01

This article details the instrumentation implemented in French nuclear power plants for the monitoring of chemical and radiochemical effluents with the aim of limiting their environmental impact. It describes the controls performed with chemical automata for the search for drifts, anomalies or pollution in a given circuit. The operation principles of the different types of chemical automata are explained as well as the manual controls performed on samples manually collected. Content: 1 - general considerations; 2 - objectives of the chemical monitoring: usefulness of continuous monitoring with automata, transmission to control rooms and related actions, redundancy of automata; 3 - instrumentation and explanations for the main circuits: principle of chemical automata monitoring, instrumentation of the main primary circuit, instrumentation of the main secondary circuit, instrumentation of the tertiary circuit, preparation of water makeup (demineralized water), other loops, instrumentation for effluents and environment monitoring, measurement principles of chemical automata, control and maintenance of chemical automata; 4 - manual controls after sampling; 5 - radiochemical monitoring: automatized radiochemical measurements, manual radiochemical measurements; 6 - conclusion

Present status and perspective of radiochemical analysis of radionuclides in Nordic countries

DEFF Research Database (Denmark)

Hou, Xiaolin; Olsson, Mattias; Togneri, Laura

2016-01-01

Radiochemical analysis plays a critical role in the determination of pure beta and alpha emitting radionuclides for environmental monitoring, radioecology, decommissioning, nuclear forensics and geological dating. A remarkable development on radiochemical analysis has been achieved in the past...... of radionuclides, especially in Nordic countries; some requirements from nuclear industries and research organizations, as well as perspectives on the development of radiochemical analysis are discussed....

Radiochemical and instrumental neutron activation analysis - recent trends

International Nuclear Information System (INIS)

Dams, R.

1990-01-01

Recent trends of radiochemical and instrumental neutron activation analysis are discussed. Novel developments include the application of cyclic and pulsed activation, better energy resolution with hyperpure germanium detectors, and use of pulse processing systems allowing extremely high count rates of very short-lived isotopes. Further development is anticipated in the field of speciation in biological and environmental studies. Radiochemical methods have led to accurate determinations at the ng/g level. A promising future is expected for neutron activation techniques. (orig.)

Radiochemical verification and validation in the environmental data collection process

International Nuclear Information System (INIS)

Rosano-Reece, D.; Bottrell, D.; Bath, R.J.

1994-01-01

A credible and cost effective environmental data collection process should produce analytical data which meets regulatory and program specific requirements. Analytical data, which support the sampling and analysis activities at hazardous waste sites, undergo verification and independent validation before the data are submitted to regulators. Understanding the difference between verification and validation and their respective roles in the sampling and analysis process is critical to the effectiveness of a program. Verification is deciding whether the measurement data obtained are what was requested. The verification process determines whether all the requirements were met. Validation is more complicated than verification. It attempts to assess the impacts on data use, especially when requirements are not met. Validation becomes part of the decision-making process. Radiochemical data consists of a sample result with an associated error. Therefore, radiochemical validation is different and more quantitative than is currently possible for the validation of hazardous chemical data. Radiochemical data include both results and uncertainty that can be statistically compared to identify significance of differences in a more technically defensible manner. Radiochemical validation makes decisions about analyte identification, detection, and uncertainty for a batch of data. The process focuses on the variability of the data in the context of the decision to be made. The objectives of this paper are to present radiochemical verification and validation for environmental data and to distinguish the differences between the two operations

Radiochemical analysis of military nuclear facilities

International Nuclear Information System (INIS)

Bayramov, A.A.; Bayramova, S.M.

2012-01-01

Full text : Radiochemical Analysis is a branch of analytical chemistry comprising an aggregate of methods for qualitatively determining the composition and content of radioisotopes in the products of transformations. Safety and minimization of radiation impact on human and environment are important demand of operation of Military Nuclear Facilities (MNF). In accordance of recommendations of International Commission on Radiological Protection there are next objects of radiochemical analysis: 1) potential sources of radiochemical pollution; 2) environment (objects of environment, human environment including buildings, agricultural production, water, air et al.); 3) human himself (determination of dose from external and internal radiation, chemical poisoning). The chemical analysis can be carried out using, for example, the Gas Chromatography instrument whish separates chemical mixtures and identifies the components at a molecular level. It is one of the most accurate tools for analyzing environmental samples. The Gas Chromatography works on the principle that a mixture will separate into individual substances when heated. The heated gases are carried through a column with an inert gas (such as helium). As the separated substances emerge from the column opening, they flow into the Mass Spectrometry. Mass spectrometry identifies compounds by the mass of the analyte molecule. Newly developed portable Gas Chromatography and Mass Spectrometry are techniques that can be used to separate volatile organic compounds and pesticides. Other uses of Gas Chromatography, combined with other separation and analytical techniques, have been developed for radionuclides, explosive compounds such as royal demolition explosive and trinitrotoluene, and metals. So, based on the many years experience of operation of dangerous MNF, in concordance with norms of radiation and chemical safety it was considered that the tasks of the radiochemical analysis of Military Nuclear Facilities include

A modified Poisson-Boltzmann equation applied to protein adsorption.

Science.gov (United States)

Gama, Marlon de Souza; Santos, Mirella Simões; Lima, Eduardo Rocha de Almeida; Tavares, Frederico Wanderley; Barreto, Amaro Gomes Barreto

2018-01-05

Ion-exchange chromatography has been widely used as a standard process in purification and analysis of protein, based on the electrostatic interaction between the protein and the stationary phase. Through the years, several approaches are used to improve the thermodynamic description of colloidal particle-surface interaction systems, however there are still a lot of gaps specifically when describing the behavior of protein adsorption. Here, we present an improved methodology for predicting the adsorption equilibrium constant by solving the modified Poisson-Boltzmann (PB) equation in bispherical coordinates. By including dispersion interactions between ions and protein, and between ions and surface, the modified PB equation used can describe the Hofmeister effects. We solve the modified Poisson-Boltzmann equation to calculate the protein-surface potential of mean force, treated as spherical colloid-plate system, as a function of process variables. From the potential of mean force, the Henry constants of adsorption, for different proteins and surfaces, are calculated as a function of pH, salt concentration, salt type, and temperature. The obtained Henry constants are compared with experimental data for several isotherms showing excellent agreement. We have also performed a sensitivity analysis to verify the behavior of different kind of salts and the Hofmeister effects. Copyright © 2017 Elsevier B.V. All rights reserved.

Automated radiochemical processing for clinical PET

International Nuclear Information System (INIS)

Padgett, H.C.; Schmidt, D.G.; Bida, G.T.; Wieland, B.W.; Pekrul, E.; Kingsbury, W.G.

1991-01-01

With the recent emergence of positron emission tomography (PET) as a viable clinical tool, there is a need for a convenient, cost-effective source of the positron emitter-labeled radiotracers labeled with carbon-11, nitrogen-13, oxygen-15, and fluorine-18. These short-lived radioisotopes are accelerator produced and thus, require a cyclotron and radiochemistry processing instrumentation that can be operated 3 in a clinical environment by competant technicians. The basic goal is to ensure safety and reliability while setting new standards for economy and ease of operation. The Siemens Radioisotope Delivery System (RDS 112) is a fully automated system dedicated to the production and delivery of positron-emitter labeled precursors and radiochemicals required to support a clinical PET imaging program. Thus, the entire RDS can be thought of as an automated radiochemical processing apparatus

4-Hydroxyhexenal- and 4-Hydroxynonenal-Modified Proteins in Pterygia

Directory of Open Access Journals (Sweden)

Ichiya Sano

2013-01-01

Full Text Available Oxidative stress has been suspected of contributing to the pathogenesis of pterygia. We evaluated the immunohistochemical localization of the markers of oxidative stress, that is, the proteins modified by 4-hydroxyhexenal (4-HHE and 4-hydroxynonenal (4-HNE, which are reactive aldehydes derived from nonenzymatic oxidation of n-3 and n-6 polyunsaturated fatty acids, respectively. In the pterygial head, labeling of 4-HHE- and 4-HNE-modified proteins was prominent in the nuclei and cytosol of the epithelium. In the pterygial body, strong labeling was observed in the nuclei and cytosol of the epithelium and proliferating subepithelial connective tissue. In normal conjunctival specimens, only trace immunoreactivity of both proteins was observed in the epithelial and stromal layers. Exposures of ultraviolet (330 nm, 48.32 ± 0.55 J/cm2 or blue light (400 nm, 293.0 ± 2.0 J/cm2 to rat eyes enhanced labeling of 4-HHE- and 4-HNE-modified proteins in the nuclei of conjunctival epithelium. Protein modifications by biologically active aldehydes are a molecular event involved in the development of pterygia.

Methods for training radiochemical technicians at ORNL

International Nuclear Information System (INIS)

Parrott, J.R.; Nicol, R.G.

1975-01-01

The training of personnel to carry out radiochemical operations at ORNL is a formidable and recurrent task since repetitive, production-type operations are not involved, and programs are constantly shifting. It is essential that provisions be made for the routine retraining of personnel if they are to make effective contributions on a continuing basis. The present training methods have emerged as a result of thirty years experience in a variety of radiochemical pilot-plant programs. These programs have included operations performed in glove boxes, hot-cell manipulator work handling high-neutron-emitting isotopes, and the entire spectrum of remote solvent extraction operations. Present methods of training and the results obtained are summarized

Rapid Radiochemical Methods for Asphalt Paving Material ...

Science.gov (United States)

Technical Brief Validated rapid radiochemical methods for alpha and beta emitters in solid matrices that are commonly encountered in urban environments were previously unavailable for public use by responding laboratories. A lack of tested rapid methods would delay the quick determination of contamination levels and the assessment of acceptable site-specific exposure levels. Of special concern are matrices with rough and porous surfaces, which allow the movement of radioactive material deep into the building material making it difficult to detect. This research focuses on methods that address preparation, radiochemical separation, and analysis of asphalt paving materials and asphalt roofing shingles. These matrices, common to outdoor environments, challenge the capability and capacity of very experienced radiochemistry laboratories. Generally, routine sample preparation and dissolution techniques produce liquid samples (representative of the original sample material) that can be processed using available radiochemical methods. The asphalt materials are especially difficult because they do not readily lend themselves to these routine sample preparation and dissolution techniques. The HSRP and ORIA coordinate radiological reference laboratory priorities and activities in conjunction with HSRP’s Partner Process. As part of the collaboration, the HSRP worked with ORIA to publish rapid radioanalytical methods for selected radionuclides in building material matrice

New radiochemical methods for determination of 237Np a 241Pu using extraction chromatography (Presentation)

International Nuclear Information System (INIS)

Strisovska, J.

2013-01-01

Thesis was focused on the development of a new methodology for the separation of anthropogenic transuranium radionuclides 237 Np a 241 Pu from different kinds of matrices. The analytical methods used in this study were based on extraction chromatography and were optimized according to the sample type. The proposed radiochemical procedure is a combination of two algorithms, which represent the separation of radionuclides by using extraction chromatographic sorbents TEVA resin and TRU resin supplied by Eichrom Technologies LLC. 239 Np a 237 Np were selectively captured on sorbent TEVA resin in oxidation state 4+. TRU resin was used for purification of plutonium fraction from interfering americium radionuclide. 242 Pu and 239 Np radionuclides as tracers have been used to monitor the radiochemical yields of separation. Before every radiochemical separation tracer radionuclide 239 Np was obtained by separation from the parent radionuclide 2 43 Am, which is in radioactive equilibrium to 239 Np. The average yield of chemical separation was 69,3% for 239 Np at 277 keV energy line and 65,9% at 228 keV energy line. The NPL AH-B08069 (2008) samples which consist of the mixture of alpha-radionuclides were used for the modification and optimization of separation method used for separation of Np and Pu in model samples. This method provided high radiochemical yields of 239,240 Pu (95,0 ± 3,5)% and 237 Np (87,9 ± 3,0)%.. Reliability of the method was verified by applying our modified separation procedures on reference materials IAEA-375 and IAEA-414 supplied by International Atomic Energy Agency. A good agreement between the results is obtained by this procedure and the certified values were found. Samples of contaminated soils from the area of Nuclear power plant A-1 Jaslovske Bohunice which is stored temporarily before disposal were analyzed using developed separation procedure. Specific activity of investigated radionuclides was determined in these samples. (author)

Radiochemical Means of Investigating Delayed Neutron Precursors

International Nuclear Information System (INIS)

Marmol, P. del

1968-01-01

Fast radiochemical methods used now for the determination of delayed neutron precursors are classified and reviewed: precipitations, solvent extractions, range experiments, milking, gas sweeping, isotopic and ion exchange, hot atom reactions and diffusion loss. Advantages and limitations of irradiation systems with respect to fast separations are discussed: external beams which allow faster separations only have low neutron fluxes, internal beams which are mostly fit for gaseous reactions; and rabbits for solution irradiations. Future prospects of radiochemical procedures are presented; among these, studies should be mostly oriented towards gaseous reactions which offer possibilities of isolating very short-lived delayed neutron precursors. Chemical procedures for delayed neutron precursor detection are compared with mass spectrometric and isotope separator techniques; it is concluded that the methods are complementary. (author)

Radiochemical Means of Investigating Delayed Neutron Precursors

International Nuclear Information System (INIS)

Marmol, P. del

1968-01-01

Fast radiochemical methods used now for the determination of delayed neutron precursors are classified and reviewed: precipitations, solvent extractions, range experiments, milking, gas sweeping, isotopic and ion exchange, hot-atom reactions and diffusion loss. Advantages and limitations of irradiation systems with respect to fast separations are discussed: external beams which allow faster separations only have low neutron fluxes, internal beams which are mostly fit for gaseous reactions; and rabbits for solution irradiations. Future prospects of radiochemical procedures are presented; among these, studies should be mostly oriented towards gaseous reactions which offer possibilities of isolating very short-lived delayed neutron precursors. Chemical procedures for delayed neutron precursor detection are compared with mass spectrometric and isotope-separator techniques; it is concluded that the methods are complementary. (author)

Radiochemical guidelines and process specifications for reactor shutdown: the EDF strategy

International Nuclear Information System (INIS)

Mole, D.; Wintergerst, M.; Meylogan, Th.; Rocher, A.; Sagot, M.J.; Bonelli, V.; Bonnefon, J.; Dupont, B.

2012-09-01

Changes to French nuclear regulations made in June 2006 [1.] have made it necessary for EDF to modify its ruling principles. These modifications required the restructuring of radiochemical guidelines to better reflect their impact on nuclear safety, the environment and radioprotection. In accordance with these aims, a new authoritative document has been produced. This ruling document identifies all parameters with a potential impact on nuclear safety, radiological releases to the environment and personnel dose rates. These diagnostic and control parameters have been identified for a reactor in production and for a reactor during shutdown. For parameters related to a reactor in production, some indicators are used to evaluate impacts on availability, radioprotection and the environment during shutdown and on outage and to anticipate mitigation ways. On the other side, several parameters related to the stages of shutdown were also directly evaluated in order to minimize the impacts. This paper describes the EDF methodology used to establish operational documents: radiochemical guidelines and process specifications, and includes the following: - description of monitored parameters and their associated areas of risk; - justification of target values, frequencies of inspection and the required actions for the monitored parameters. The sizing methodology is based on theoretical studies and on EDF operational experience analysis. By implementing in the operational and technical specifications requirements linked to nuclear safety, radioprotection and environment respect, EDF will benefit from an improved compromise between these areas as well as an increased focus. (authors)

Radiochemical purity determination by paper chromatography 2

International Nuclear Information System (INIS)

1975-01-01

The standard relates to the determination of radiochemical impurities in labelled compounds using paper chromatography. The basic terms are given as is the description of procedure and evaluation of chromatograms. (E.S.)

Radiochemical analysis for nuclear waste management in decommissioning

International Nuclear Information System (INIS)

Hou, X.

2010-07-01

The NKS-B RadWaste project was launched from June 2009. The on-going decommissioning activities in Nordic countries and current requirements and problems on the radiochemical analysis of decommissioning waste were discussed and overviewed. The radiochemical analytical methods used for determination of various radionuclides in nuclear waste are reviewed, a book was written by the project partners Jukka Lehto and Xiaolin Hou on the chemistry and analysis of radionuclide to be published in 2010. A summary of the methods developed in Nordic laboratories is described in this report. The progresses on the development and optimization of analytical method in the Nordic labs under this project are presented. (author)

Radiochemical studies of some preparation methods for phosphorus

International Nuclear Information System (INIS)

Loos-Neskovic, C.; Fedoroff, M.

1983-01-01

Various methods of radiochemical separation were tested for the determination of phosphorus in metals and alloys by neutron activation analysis. Classical methods of separation revealed some defects when they were applied to this problem. Methods using liquid extraction gave low yields and were not reproducible. Methods based on precipitation gave better results, but were not selective enough in most cases. Retention on alumina was not possible without preliminary separations. Authors studied a new radiochemical separation based on the extraction of elemental phosphorus in the gaseous phase after reduction at high temperature with carbon. Measurements with radioactive phosphorus showed that the extraction yield is better than 99%. (author)

Radiochemical analysis for nuclear waste management in decommissioning

Energy Technology Data Exchange (ETDEWEB)

Hou, X. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy. Radiation Research Div., Roskilde (Denmark))

2010-07-15

The NKS-B RadWaste project was launched from June 2009. The on-going decommissioning activities in Nordic countries and current requirements and problems on the radiochemical analysis of decommissioning waste were discussed and overviewed. The radiochemical analytical methods used for determination of various radionuclides in nuclear waste are reviewed, a book was written by the project partners Jukka Lehto and Xiaolin Hou on the chemistry and analysis of radionuclide to be published in 2010. A summary of the methods developed in Nordic laboratories is described in this report. The progresses on the development and optimization of analytical method in the Nordic labs under this project are presented. (author)

Highly Efficient Intracellular Protein Delivery by Cationic Polyethyleneimine-Modified Gelatin Nanoparticles

Directory of Open Access Journals (Sweden)

Ming-Ju Chou

2018-02-01

Full Text Available Intracellular protein delivery may provide a safe and non-genome integrated strategy for targeting abnormal or specific cells for applications in cell reprogramming therapy. Thus, highly efficient intracellular functional protein delivery would be beneficial for protein drug discovery. In this study, we generated a cationic polyethyleneimine (PEI-modified gelatin nanoparticle and evaluated its intracellular protein delivery ability in vitro and in vivo. The experimental results showed that the PEI-modified gelatin nanoparticle had a zeta potential of approximately +60 mV and the particle size was approximately 135 nm. The particle was stable at different biological pH values and temperatures and high protein loading efficiency was observed. The fluorescent image results revealed that large numbers of particles were taken up into the mammalian cells and escaped from the endosomes into the cytoplasm. In a mouse C26 cell-xenograft cancer model, particles accumulated in cancer cells. In conclusion, the PEI-modified gelatin particle may provide a biodegradable and highly efficient protein delivery system for use in regenerative medicine and cancer therapy.

Radiochemistry and radiochemical separations. A current bibliography

International Nuclear Information System (INIS)

Bujdoso, E.

1999-01-01

A current bibliography for years 1993-1996 with 159 references was compiled on radiochemistry and radiochemical separations based on the INIS Atomindex. The references are arranged in alphabetical order of first authors. (N.T.)

Sonochemical synthesis of (3-aminopropyl)triethoxysilane-modified monodispersed silica nanoparticles for protein immobilization

International Nuclear Information System (INIS)

Shen, Shou-Cang; Ng, Wai Kiong; Chia, Leonard; Dong, Yuan-Cai; Tan, Reginald B.H.

2011-01-01

Graphical abstract: 3-Aminopropyltriethoxysilane modified monodispersed silica nanoparticles were synthesized by rapid sonochemical co-condensation to achieve high capability for protein immobilization. Highlights: → Amino-modified monodispersed silica nanoparticles were synthesized by rapid co-condensation. → Strong positive charge was created by aminopropyl-modification. → Capability for immobilization of negatively charged protein was enhanced. → Electrostatic interaction between proteins and surface contributed to the enhanced adsorption. -- Abstract: 3-Aminopropyltriethoxysilane modified monodispersed silica nanoparticles were synthesized by a rapid sonochemical co-condensation synthesis procedure. The chemical nature of surface organic modifier on the obtained modified silica nanoparticle was characterized by 13 C and 29 Si MAS Nuclear Magnetic Resonance (NMR) spectroscopies, Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA)- differential scanning calorimetry (DSC). Due to the strengthened positive surface charge of the silica nanoparticles by the modification with aminopropyl groups, the capability for bovine serum albumin (BSA) adsorption was significantly increased as compared with bare silica nanoparticles. 80 mg/g BSA was adsorbed on modified silica nanoparticles, whereas only 20 mg/g BSA could be loaded on pure silica nanoparticles. The enhanced positive surface charge repelled proteins with net positive charge and the modified silica nanoparticles exhibited negligible adsorption of lysozyme, thus a selective adsorption of proteins could be achieved.

Sonochemical synthesis of (3-aminopropyl)triethoxysilane-modified monodispersed silica nanoparticles for protein immobilization

Energy Technology Data Exchange (ETDEWEB)

Shen, Shou-Cang, E-mail: shen_shoucang@ices.a-star.edu.sg [Institute of Chemical and Engineering Sciences, A-STAR (Agency for Science, Technology and Research), 1 Pesek Road, Jurong Island, Singapore 627833 (Singapore); Ng, Wai Kiong; Chia, Leonard; Dong, Yuan-Cai [Institute of Chemical and Engineering Sciences, A-STAR (Agency for Science, Technology and Research), 1 Pesek Road, Jurong Island, Singapore 627833 (Singapore); Tan, Reginald B.H., E-mail: reginald_tan@ices.a-star.edu.sg [Institute of Chemical and Engineering Sciences, A-STAR (Agency for Science, Technology and Research), 1 Pesek Road, Jurong Island, Singapore 627833 (Singapore); Department of Chemical and Biomolecular Engineering, The National University of Singapore, 4 Engineering Drive 4, Singapore 117576 (Singapore)

2011-10-15

Graphical abstract: 3-Aminopropyltriethoxysilane modified monodispersed silica nanoparticles were synthesized by rapid sonochemical co-condensation to achieve high capability for protein immobilization. Highlights: {yields} Amino-modified monodispersed silica nanoparticles were synthesized by rapid co-condensation. {yields} Strong positive charge was created by aminopropyl-modification. {yields} Capability for immobilization of negatively charged protein was enhanced. {yields} Electrostatic interaction between proteins and surface contributed to the enhanced adsorption. -- Abstract: 3-Aminopropyltriethoxysilane modified monodispersed silica nanoparticles were synthesized by a rapid sonochemical co-condensation synthesis procedure. The chemical nature of surface organic modifier on the obtained modified silica nanoparticle was characterized by {sup 13}C and {sup 29}Si MAS Nuclear Magnetic Resonance (NMR) spectroscopies, Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA)- differential scanning calorimetry (DSC). Due to the strengthened positive surface charge of the silica nanoparticles by the modification with aminopropyl groups, the capability for bovine serum albumin (BSA) adsorption was significantly increased as compared with bare silica nanoparticles. 80 mg/g BSA was adsorbed on modified silica nanoparticles, whereas only 20 mg/g BSA could be loaded on pure silica nanoparticles. The enhanced positive surface charge repelled proteins with net positive charge and the modified silica nanoparticles exhibited negligible adsorption of lysozyme, thus a selective adsorption of proteins could be achieved.

Method of determination of radiochemical purity of gallium-67 citrate injection

International Nuclear Information System (INIS)

Wang Quanji

1985-01-01

A simple method is used to compare the effect of five developing agents on the radiochemical purity of neutral products of 67 GaCit and on Rsub(f) values. Two preferable developing agents are recommended as suitable for the identification of 67 GaCit injection in its production. The effect of six pH values of different developing agents on radiochemical purity, Rsub(f) and chromatogram are compared for the neutral products. The results of the experiments show that the ascending paper chromatography with 1:2:4 pyridine/ethanol/water and 85:15 methanol/water is preferable for the determination of the radiochemical purity of 67 GaCit. The other developing agents also can be used if there are not any impurities except gallium radioisotopes

Proceedings of the Tripartite Seminar on Nuclear Material Accounting and Control at Radiochemical Plants

International Nuclear Information System (INIS)

1999-01-01

The problems of creation and operation of nuclear materials (NM) control and accounting systems and their components at radiochemical plants were discussed in seminar during November 2-6 of 1998. There were 63 Russian and 25 foreign participants in seminar. The seminar programme includes following sessions and articles: the aspects of State NM control and accountancy; NM control and accounting in radiochemical plants and at separate stages of reprocessing of spent nuclear fuel and irradiated fuel elements of commercial reactors; NM control and accountancy in storage facilities of radiochemical plants; NM control and accounting computerization, material balance assessment, preparation of reports; qualitative and quantitative measurements in NM control and accounting at radiochemical plants destructive analysis techniques [ru

Comparison of different thin layer detection techniques to determine the radiochemical purity of radiopharmaceuticals

International Nuclear Information System (INIS)

Hammermaier, A.; Reich, E.; Boegl, W.

1985-01-01

Ten radiopharmaceuticals frequently used in clinical treatment were examined as to their radiochemical purity by paper and thin layer chromatography or electrophoresis, respectively. It is known that radiochemical impurities may result in an unnecessary exposure of the patients to be examined. Other than determining the radiochemical purity of several radiopharmaceuticals, a comparison of the different measuring methods of distributing activity on radiochromatograms or electropherograms is intended by this study. For this, the activity distribution in the developed radiochromatograms was assessed by four different measuring methods (TLC-linear analyzer, TLC-scanner with NaI(Tl) detector, TLC-scanner with gas flow counter and NaI(Tl) well-typ counter). As shown by the above analysis, only the TLC-linear analyzer and the NaI(Tl) well-typ counter (measurement of chromatograms or electropherograms cut into strips) are generally suitable methods for determining the radiochemical purity of radiochemicals, the TLC-scanner with gas flow counter is usable in most cases, while TLC-scanner with NaI(Tl) detector is yielding unsatisfactory results. (orig.) [de

Radiochemical studies on nuclear fission at Trombay

Indian Academy of Sciences (India)

227Ac to 245Cm were determined by radiochemical methods which involved ... foil, followed by direct γ counting using high resolution Ge(Li) detector was also ... the stiffness to mass asymmetric distortion decreases on either side of lead.Also ...

Radiochemical synthesis of etomoxir

Energy Technology Data Exchange (ETDEWEB)

Abbas, Hafiz G. [Institute of Nuclear Medicine and Oncology (INMOL), New Campus Road, Lahore (Pakistan); Yunus, M. [University of the Punjab, New Campus Road, Lahore (Pakistan); Feinendegen, Ludwig E., E-mail: feinendegen@gmx.ne [Department of Nuclear Medicine, Heinrich-Heine University Duesseldorf, Wannental 45, 88131 Lindau (Germany)

2011-02-15

Sodium 2-{l_brace}6-(4-chlorophenoxy)hexyl{r_brace}oxirane-2-carboxylate (Etomoxir) inhibits transport of fatty acids via the carnitine shuttle into mitochondria of muscle cells and prevents long chain fatty acids from providing energy through {beta}-oxidation especially for muscle contraction. The objective of this synthesis is to develop a method for radioiodination of Etomoxir in order to explore its potential in diagnostic metabolic studies and molecular imaging. Thus, a method is described for the radiochemical synthesis and purification of ethyl 2-{l_brace}6-(4-[{sup 131}I]iodophenoxy)hexyl{r_brace}oxirane-2-carboxylate (3) and 2-{l_brace}6-(4-[{sup 131}I]iodo-phenoxy)hexyl{r_brace}oxirane-2-carboxylic acid (4). For the synthesis of these new agents, ethyl 2-{l_brace}6-(4-bromophenoxy)hexyl{r_brace}oxirane-2-carboxylate (1) and 2-{l_brace}6-(4-bromophenoxy)hexyl{r_brace}oxirane-2-carboxylic acid (2) were refluxed with [{sup 131}I]NaI in the presence of anhydrous acetone at a temperature of 80 {sup o}C and 90 {sup o}C for a period of 3-4 hours, respectively. The method of radiolabeling, based on the nucleophilic exchange reaction, resulted in a radiochemical yield of 43% and 67% for compounds 3 and 4, respectively. This paper reports on the labeling of etomoxir with radioiodine as {sup 124}I labeled etomoxir may be of great importance in molecular imaging.

Radiochemical methods

International Nuclear Information System (INIS)

Geary, W.J.

1986-01-01

This little volume is one of an extended series of basic textbooks on analytical chemistry produced by the Analytical Chemistry by Open Learning project in the UK. Prefatory sections explain its mission, and how to use the Open Learning format. Seventeen specific sections organized into five chaptrs begin with a general discussion of nuclear properties, types, and laws of nuclear decay and proceeds to specific discussions of three published papers (reproduced in their entirety) giving examples of radiochemical methods which were discussed in the previous chapter. Each section begins with an overview, contains one or more practical problems (called self-assessment questions or SAQ's), and concludes with a summary and a list of objectives for the student. Following the main body are answers to the SAQ's, and several tables of physical constants, SI prefixes, etc. A periodic table graces the inside back cover

Safety and Waste Management for SAM Radiochemical Methods

Science.gov (United States)

The General Safety and Waste Management page offers section-specific safety and waste management details for the radiochemical analytes included in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).

Decontamination and decommission of a radiochemical laboratory building complex

International Nuclear Information System (INIS)

Zoubek, Norbert

2008-01-01

Full text: Handling of unsealed radioactive substances for research and development purposes in chemical or pharmaceutical industries or research centres as well as production of radioactive substances (e.g. for applications in nuclear medicine or industry) requires operation of special radiochemical laboratories. In general, operation of radiochemical laboratories is strongly regulated by the government and national authorities. The operator needs a permit related to radiological protection. In general, technical requirements for such facilities are very high. To ensure high safety standards with respect to the employees and the environment, several radiological protection measures have to be taken. These measures (for example special shielding or ventilation and waste water systems) depend on various factors, e.g. activity in use, kind of nuclides, chemical properties and volatility of substances. In order to close-down such radiochemical laboratories some radiological protection measures have to be maintained to ensure protection of both humans and the environment induced by possible residual contaminations within the facility including technical inventory. However, a later reuse of the facility as a non-radioactive facility requires removal of all radioactive contamination with respect to national regulation. Resulting radioactive wastes have to be disposed of under control of competent authorities. Based on the experience of a decontamination and decommission project for a former radiochemical laboratory complex, the main steps necessary to release such a facility are discussed. Analytical aspects of initial conditions, necessary organisational structures within the project, resources needed estimation and exploration of the radiological situation in the laboratory, elaboration of a measuring strategy and decontamination methods as well as different waste disposal routes in relation to different waste types are reported. (author)

Determination of thorium in native gold by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Liu, Y.; Kraehenbuehl, U.

1995-01-01

Thorium concentrations in 11 native gold samples from different sources, e.g. placer gold, vein and lode gold were determined. Thorium was determined by radiochemical separation and measurement of protactinium from irradiated native gold samples. The chemical yield of the separation procedures is 90%. Other elements were measured by gamma-ray spectroscopy. The radiochemical separation procedures described in this work make accurate determination of Th concentrations in native gold at picogram concentrations possible. (orig.)

Automated radiochemical synthesis and biodistribution of [11C]l-α-acetylmethadol ([11C]LAAM)

International Nuclear Information System (INIS)

Sai, Kiran Kumar Solingapuram; Fan, Jinda; Tu, Zhude; Zerkel, Patrick; Mach, Robert H.; Kharasch, Evan D.

2014-01-01

Long-acting opioid agonists methadone and l-α-acetylmethadol (LAAM) prevent withdrawal in opioid-dependent persons. Attempts to synthesize [ 11 C]-methadone for PET evaluation of brain disposition were unsuccessful. Owing, however, to structural and pharmacologic similarities, we aimed to develop [ 11 C]LAAM as a PET ligand to probe the brain exposure of long-lasting opioids in humans. This manuscript describes [ 11 C]LAAM synthesis and its biodistribution in mice. The radiochemical synthetic strategy afforded high radiochemical yield, purity and specific activity, thereby making the synthesis adaptable to automated modules. - Highlights: • Radiochemical synthesis of opioid [ 11 C]l-α-acetylmethadol (LAAM) described for the first time. • High radiochemical yield, purity and specific activity. • Easily reproducible and adaptable synthesis to any C-11 automated modules. • [ 11 C]LAAM utility as a PET radiopharmaceutical for assessing brain penetration

Radiochemical separation and their application to neutron activation analysis technique

International Nuclear Information System (INIS)

Turel, Z.R.

2013-01-01

The present paper discusses the development of some new, rapid and selective method for the radiochemical separation and estimation of elements such as, Co(II) 2-3 , Ir(III) 4 , Au(III) 5 , Pt(IV), Pd(II), Os(IV) 6 , Cu(II), Ag(I), Mo(VI), Ni(II), Zn(II), Cd(II), Hg(II), Cs(I), Sb(III), La(III), Sc(III) etc. using various reagents. Various parameters such as pH, time of equilibrium, effect of anions and cations, effect of reagent etc. has been determined employing tracers of the elements under consideration and will be discussed. The method is made highly selective by the use of appropriate masking agent. The stoichiometry of metal reagent is determined by the substoichiometric method. Some examples of multielemental radiochemical separation methods thus developed which have been applied in determining the elements by radiochemical thermal neutron activation analysis will be presented and discussed. The implications of the results on the reference system will also be accounted. Statistical evaluation with reference to accuracy, precision and sensitivity will also be presented

Protein-modified nanocrystalline diamond thin films for biosensor applications.

Science.gov (United States)

Härtl, Andreas; Schmich, Evelyn; Garrido, Jose A; Hernando, Jorge; Catharino, Silvia C R; Walter, Stefan; Feulner, Peter; Kromka, Alexander; Steinmüller, Doris; Stutzmann, Martin

2004-10-01

Diamond exhibits several special properties, for example good biocompatibility and a large electrochemical potential window, that make it particularly suitable for biofunctionalization and biosensing. Here we show that proteins can be attached covalently to nanocrystalline diamond thin films. Moreover, we show that, although the biomolecules are immobilized at the surface, they are still fully functional and active. Hydrogen-terminated nanocrystalline diamond films were modified by using a photochemical process to generate a surface layer of amino groups, to which proteins were covalently attached. We used green fluorescent protein to reveal the successful coupling directly. After functionalization of nanocrystalline diamond electrodes with the enzyme catalase, a direct electron transfer between the enzyme's redox centre and the diamond electrode was detected. Moreover, the modified electrode was found to be sensitive to hydrogen peroxide. Because of its dual role as a substrate for biofunctionalization and as an electrode, nanocrystalline diamond is a very promising candidate for future biosensor applications.

Development of radiochemical method of analysis of binding of tritium labeled drotaverine hydrochloride with human blood serum albumin

International Nuclear Information System (INIS)

Kim, A.A.; Djuraeva, G.T.; Shukurov, B.V.; Mavlyanov, I.R.

2004-01-01

Full text: The albumin, being a basic functional linkage of numerous endogenous and exogenous substances is the most important protein of blood plasma. At the diseases connected to liver disfunction, collected in blood metabolite reduce connecting ability of albumino. The aim of the present research was a development of radiochemical method of determination of ability of albumin to bind the tritium labeled preparation drotaverine hydrochloride (no - spa). We had developed a micromethod of definition of connecting ability of albumin, allowing to analyse 20 mkl of blood serum. The method consists in incubation of tritium labeled drotaverine hydrochloride with blood serum in vitro, the following fractionation of serum proteins by gel - filtration on a microcolumn with Sephadex G-25, and direct measurement of the radioactivity connected to fraction of proteins of blood serum. The method has been tested on a series of blood serum of control group of healthy people and on a series of blood serum of patients with hepatitis B. We received quantitative characteristics of binding of drotaverine hydrochloride with albumin of patients with hepatitis B. It was preliminary established that binding ability of serum albumin of children with various forms of acute virus hepatitis tends to decrease in comparison with group of the control. Advantage of the developed radiochemical method is high precision and the high sensitivity of detection of infringement of binding ability of albumin. Application of tritium labeled drotaverine hydrochloride allows to measure directly levels of binding of a preparation with albumin

Radiolabeling, quality control and radiochemical purity assessment of 99mTc-HYNIC-TOC

International Nuclear Information System (INIS)

Melero, Laura T.U.H.; Araujo, Elaine B.; Mengatti, Jair

2009-01-01

Somatostatine receptors are widely expressed by several tumors, especially of the neuroendocrine origin. In vivo images of these tumors using radiolabeled somatostatine analogues became a useful clinical tool in oncology. The aim of this work was the radiolabeling of the somatostatine analogue HYNIC-TOC with 99mTc as well as the evaluation of the radiochemical stability and quality control of labeled complex. 99mTc-HYNIC-TOC was produced by labeling conditions using 20 μg of peptide, 20 mg of tricine and 10 mg of EDDA as coligands, 1110 MBq of 99mTc (99Mo-99mTc IPEN-TEC generator) and 15 μg of SnCl 2 .2H 2 O. The reaction proceeds for 10 minutes at boiling water bath. Radiochemical purity of labeled preparation was evaluated by different chromatographic systems: ITLC-SG in methanol:ammonium acetate (1:1); TLC-SG in sodium citrate buffer 0.1 N pH 5.0 and methylethylketone, and HPLC employing column C-18, 5 μm, 4.6 mm x 250 mm, UV (220 nm), radioactivity detectors, 1 mL/minute flow of acetonitrile and trifluoroacetic acid solution 0.1 %. Labeled compound has been found radiochemically stable for 5 hours and radiochemical purity was higher than 90 %. The thin layer chromatographic systems enabled the separation of radiochemical species presented in the labeled mixture as well as HPLC system. The labeling procedure studied resulted in high radiochemical yield and easy preparation. Future works include the preparation of a lyophilized reagent to make feasible the preparation of 99mTc-HYNIC-TOC at nuclear medicine services in order to study the clinical potential of the radiopharmaceutical in diagnostic and staging of neuroendocrine tumors. (author)

Miniaturized chromatographic radiochemical procedure for 131I - MIBG

International Nuclear Information System (INIS)

Barboza, M.F. de; Pereira, N.S. de; Colturato, M.T.; Silva, C.P.G. da.

1989-12-01

Different solvents were used in paper chromatographic methods to obtain the best system in routine radiochemical control for 131 I-MIBG produced at IPEN-CNEN/SP. The dates were compared with those obtained with eletrophoresis method in buffer acetate, pH=4.5, 350V, during 40 minutes. The stability of the labeled compound store under 4 0 C was studied during 15 days. Miniaturized chromatographic procedures were established using Whatman 3MM (8x1cm) and n-butanol-:acetic acid: water (S:2:1) as a solvent. the Rf values were: 0.3 (I - ) and 1.0 (MIBG). The radiochemical purity was 99.3 and 99.2% (first day) obtained with eletrophoresis and miniaturized chromatographic procedures, respectively and, 84.7% after 15 days of its preparation. It is a rapid, practical and reproductive method. (author) [pt

Synthesis of N-[methyl-11C]hydromorphone by using multivariate strategies for optimization of radiochemical yields

International Nuclear Information System (INIS)

Rimland, Annika; Bergson, Goeran; Obenius, Ulf; Sjoeberg, Stefan; Langstroem, Bengt

1987-01-01

The synthesis of N-[methyl- 11 C]hydromorphone has been performed by using [ 11 C]methyl iodide and desmethyl hydromorphone in a mixture of dimethylsulphoxide and dimethylformamide as solvent. Optimization of the radiochemical yield by varying the reaction conditions was performed by using multivariate strategies. The labelled hydromorphone was obtained in 72% radiochemical yield in the alkylation reaction with [ 11 C]-methyl iodide, counted from the end of the [ 11 C]methyl iodide synthesis. N-[Methyl- 11 C]hydromorphone was obtained as a ready injectable pharmaceutical solution with a total synthesis time of 40 min and in a 10% total radiochemical yield, with a radiochemical purity > 99.5%, according to HPLC analysis. (author)

A radiochemical assay for biotin in biological materials

International Nuclear Information System (INIS)

Hood, R.L.

1975-01-01

A radiochemical assay for biotin is described. The assay was sensitive to one nanogram and simple enough for routine biotin analyses. The assay yielded results which were comparable to those obtained from a microbiological assay using Lactobacillus plantarum. (author)

Characterisation of chemically-modified proteins by electrospray ionisation mass spectrometry

International Nuclear Information System (INIS)

Bennett, K.L.

1996-09-01

Electrospray mass spectrometry (ESI-MS) has been used to examine a range of intact monoclonal antibodies (MAbs), antibody fragments such as F(ab') 2 , F ab and F c , chemically-modified fragments and a range of other chemically-modified peptides and proteins as part of a broader study aimed at establishing ESI-MS as a method for the characterisation of radioimmunoconjugates (radiolabelled monoclonal antibodies). For example, the addition of up to 10 biotin molecules to the 'papain-sensitive' 50 kDa F ab fragment can be easily detected in ESI mass spectra. For intact MAbs, however, it is only possible to detect average shifts in the mass of intact antibodies following modification. Successful ESI-MS analysis of complexes formed between chelators and other small molecules conjugated to synthetic peptides, hen egg-white Iysozyme (HEL) (M r 14 306) and horse heart myoglobin (M r 16 951) has been demonstrated. ESI-MS offers considerable advantages compared with existing methods for the characterisation of chemically-conjugated proteins including speed and sensitivity of analysis and the capability for obtaining specific structural information. The conditions for ESI-MS of intact MAbs and MAb fragments have been examined in detail and it was found that 150 kDa MAbs generally required lower sample concentration and higher skimmer potentials compared with the 50 kDa F ab fragment and other lower molecular weight proteins. In addition, the m/z range over which ions from MAbs were observed was higher (m/z ∼2000-4500) than for smaller proteins. ESI-MS was also found to be useful for probing the action of the protease papain, that is used to generate MAb fragments (F(ab) '2, F ab and F c ). Further, different sensitivities to papain for different MAb preparations was demonstrated. Finally, the tandem mass spectra of a range of peptides modified by iodine and biotin were examined. In the case of biotinylated peptides, a characteristic fragment ion was identified that could

The analytical of radiochemical purity of tumor receptor imaging agent 99Tcm-octreotide

International Nuclear Information System (INIS)

Wang Xufu; Zuo Shuyao; Shao Wenbo; Wang Guoming; Sun Jianwen; Zhang Qin

2003-01-01

The radiochemical purity of tumor receptor imaging agent 99 Tc m -octreotide is measured by High Pressure Liquid Chromatography (HPLC) and two systems of chromatography combining method of silver stain. The results show that the radiochemical purity of 98 Tc m -octreotide measured by both methods are effective and correct. It can separate 99 Tc m -octreotide from other radioactive compositions correctly and effectively

Radiolabeling, quality control and radiochemical purity assessment of {sup 99m}Tc-HYNIC-TOC

Energy Technology Data Exchange (ETDEWEB)

Melero, Laura T.U.H.; Araujo, Elaine B.; Mengatti, Jair [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2009-07-01

Somatostatine receptors are widely expressed by several tumors, especially of the neuroendocrine origin. In vivo images of these tumors using radiolabeled somatostatine analogues became a useful clinical tool in oncology. The aim of this work was the radiolabeling of the somatostatine analogue HYNIC-TOC with 99mTc as well as the evaluation of the radiochemical stability and quality control of labeled complex. 99mTc-HYNIC-TOC was produced by labeling conditions using 20 {mu}g of peptide, 20 mg of tricine and 10 mg of EDDA as coligands, 1110 MBq of 99mTc (99Mo-99mTc IPEN-TEC generator) and 15 {mu}g of SnCl{sub 2}.2H{sub 2}O. The reaction proceeds for 10 minutes at boiling water bath. Radiochemical purity of labeled preparation was evaluated by different chromatographic systems: ITLC-SG in methanol:ammonium acetate (1:1); TLC-SG in sodium citrate buffer 0.1 N pH 5.0 and methylethylketone, and HPLC employing column C-18, 5 {mu}m, 4.6 mm x 250 mm, UV (220 nm), radioactivity detectors, 1 mL/minute flow of acetonitrile and trifluoroacetic acid solution 0.1 %. Labeled compound has been found radiochemically stable for 5 hours and radiochemical purity was higher than 90 %. The thin layer chromatographic systems enabled the separation of radiochemical species presented in the labeled mixture as well as HPLC system. The labeling procedure studied resulted in high radiochemical yield and easy preparation. Future works include the preparation of a lyophilized reagent to make feasible the preparation of 99mTc-HYNIC-TOC at nuclear medicine services in order to study the clinical potential of the radiopharmaceutical in diagnostic and staging of neuroendocrine tumors. (author)

Evaluation of radiochemical purities of some radiopharmaceuticals in Shiraz Namazi teaching hospital

Directory of Open Access Journals (Sweden)

Hossein Sadeghpour

2015-03-01

Full Text Available Many radiopharmaceuticals, as a special group of drugs, are eventually prepared at the nuclear medicine departments of the hospitals. Therefore, their quality control procedures such as sterility tests, radionuclide, radiochemical and chemical purity should be carried out in the hospitals. In this study, radiochemical purity for more than 300 preparations of three different radiopharmaceutical formulations from commercial kits were tested using instant thin layer chromatography. The formulations 99mTc-DTPA, 99mTc-MDP and 99mTc-MIBI were obtained from Pars Isotope Co. Several paper chromatographic systems including standard and factory recommended thin layer chromatography systems were used in this study. In addition different equipments for detection of radioactivity in paper chromatography like gamma camera and dose calibrator were used. The results showed that the most observed impurities were hydrolyzed reduced technetium (HR-Tc. There were no significant differences between calculated 99mTc-MIBI radiochemical purities when the radioactive detection device was gamma camera instead of dose calibrator. In case of 99mTc-DTPA and 99mTc-MDP, there were significant differences in detection of HR-Tc. On the contrary, no significant differences in free pertechnetate were observed when package insert procedures for quality control were used instead of those recommended in the references. Finally, we observed that the package insert procedures for quality control can offer higher radiochemical purities.

Instant thin layer chromatography (ITLC) - the most true and convenient method for the determination of radiochemical purity of Tc-99m Labeled radiopharmaceuticals

International Nuclear Information System (INIS)

Anwar-Ul-Azim, M.; Ansari, M.I.H.

2007-01-01

Full text: Determination of radiochemical purity usually involves paper chromatography method or some column chromatography such as ion exchange or gel filtration technique. In this study, a modified chromatography method with thin-layer support called instant thin Layer chromatography (ITLC) was used for the measurement of radiochemical purity. The aim of the study was to present instant thin layer chromatography-Silica-Gel (ITLC-SG) technique as a fairly rapid , convenient and inexpensive system for the screening of radiochemical impurities of 99mTc-labeled radiopharmaceuticals resulting from physical , chemical and/or radiation decomposition. Materials and Methods: The experiment was carried out at the Institute of Nuclear Medicine and Ultrasound, Dhaka for a period of 10 months from August '05 to May '06. Radiochemical purity of seven types of 99mTc-labeled radiopharmaceuticals, namely 99mTc-DTPA,99mTc- MI I, 99m Tc - HDP, 99m Tc - DMSA, 99m Tc - Tetofosmin, 99mTc-Fyton and 99mTc-ECD were measured by the use of two solvent dual-instant thin layer chromatography systems. Commercially available instant thin layer chromatography plate ( 20cm x20cm) impregnated with silica gel (ITLC-SG: Merck, Germany) was used as a stationary phase for the measurement of radiochemical impurities.Acetone, Ethyl methyl ketone, chloroform and methanol were used to measure the amount of free pertechnetate in the labelled radiopharmaceuticals and 0.9% saline was used in all cases as solvent (Mobile phase) to measure the amount of the hydrolyzed-reduced technetium colloid. Results: The results showed that the measured radiochemical purity of 99mTc-DTPA, 99mTc-MIBI, 99mTc-HDP, 99mTc-DMSA, 99mTc-Tetofosmin, 99mTc-Fyton and 99mTc-ECD were acceptable for all the studied samples except two samples of 99mTc-MIBI, one sample of 99mTc-Fyton and two samples of 99mTc-ECD, where the measured radiochemical purity were not within the acceptable RCP limits of commonly used radiopharmaceuticals (RCP

Current studies of biological materials using instrumental and radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Fardy, J.J.; McOrist, G.D.; Farrar, Y.J.

1985-01-01

Instrumental neutron activation analysis still remains the preferred option when analysing the trace element distribution in a wide rage of materials by neutron activation analysis. However, when lower limits of detection are required or major interferences reduce the effectiveness of this technique, radiochemical neutron activation analysis is applied. This paper examines the current use of both methods and the development of rapid radiochemical techniques for analysis of the biological materials, hair, cow's milk, human's milk, milk powder, blood and blood serum

Imaging the lipidome: omega-alkynyl fatty acids for detection and cellular visualization of lipid-modified proteins.

Science.gov (United States)

Hannoush, Rami N; Arenas-Ramirez, Natalia

2009-07-17

Fatty acylation or lipid modification of proteins controls their cellular activation and diverse roles in physiology. It mediates protein-protein and protein-membrane interactions and plays an important role in regulating cellular signaling pathways. Currently, there is need for visualizing lipid modifications of proteins in cells. Herein we report novel chemical probes based on omega-alkynyl fatty acids for biochemical detection and cellular imaging of lipid-modified proteins. Our study shows that omega-alkynyl fatty acids of varying chain length are metabolically incorporated onto cellular proteins. Using fluorescence imaging, we describe the subcellular distribution of lipid-modified proteins across a panel of different mammalian cell lines and during cell division. Our results demonstrate that this methodology is a useful diagnostic tool for analyzing the lipid content of cellular proteins and for studying the dynamic behavior of lipid-modified proteins in various disease or physiological states.

Northern Marshall Islands Radiological Survey: a quality-control program for a radiochemical analyses

International Nuclear Information System (INIS)

Jennings, C.D.; Mount, M.E.

1983-08-01

More than 16,000 radiochemical analyses were performed on about 5400 samples of soils, vegetation, animals, fish, invertebrates, and water to establish amounts of 90 Sr, 137 Cs, 241 Am, and plutonium isotopes in the Northern Marshall Islands. Three laboratories were contracted by Lawrence Livermore National Laboratory to perform the radiochemical analyses: Environmental Analysis Laboratory (EAL), Richmond, California; Eberline Instrument Corporation (EIC), Albuquerque, New Mexico; and Laboratory of Radiation Ecology (LRE), University of Washington, Seattle, Washington. The analytical precision and accuracy were monitored by regularly including duplicate samples and natural matrix standards in each group of about 100 samples analyzed. Based on the duplicates and standards, over 83% of the radiochemical analyses in this survey were acceptable - 97% of the analyses by EAL, 45% of the analyses by EIC, and 98% of the analyses by LRE

Determination of radiochemical purity and pharmacokinetic parameters of sup(99m)Tc-sulphur colloid and sup(99m)Tc-tin colloid

International Nuclear Information System (INIS)

Jovanovic, V.; Konstantinovska, D.; Milivojevic, K.; Bzenic, J.

1981-01-01

Labelling yield and radiochemical purity, higher than 95%, of sup(99m)Tc-colloid preparations were determined by using the paper chromatography method. Less than 3% of labelled citric acid, added to the preparation as a buffer solution, has been found in sup(99m)Tc-sulphur colloid. High radiochemical purity and optimum size of colloid particles has also been proved by biodistribution studies on experimental animals. The analysis performed has shown that more than 50% of sup(99m)Tc-colloid preparations excreted by urine is sup(99m)TcO - , the remaining past 50% being protein bound sup(99m)Tc. Biological half-time of excretion of the fast phase is the same for both preparations, i.e. 10 min, while for the slow component it is 120 min in sup(99m)Tc-S-colloid and 160 min in sup(99m)Tc-Sn colloid. (orig.) [de

Using the Ubiquitin-modified Proteome to Monitor Distinct and Spatially Restricted Protein Homeostasis Dysfunction.

Science.gov (United States)

Gendron, Joshua M; Webb, Kristofor; Yang, Bing; Rising, Lisa; Zuzow, Nathan; Bennett, Eric J

2016-08-01

Protein homeostasis dysfunction has been implicated in the development and progression of aging related human pathologies. There is a need for the establishment of quantitative methods to evaluate global protein homoeostasis function. As the ubiquitin (ub) proteasome system plays a key role in regulating protein homeostasis, we applied quantitative proteomic methods to evaluate the sensitivity of site-specific ubiquitylation events as markers for protein homeostasis dysfunction. Here, we demonstrate that the ub-modified proteome can exceed the sensitivity of engineered fluorescent reporters as a marker for proteasome dysfunction and can provide unique signatures for distinct proteome challenges which is not possible with engineered reporters. We demonstrate that combining ub-proteomics with subcellular fractionation can effectively separate degradative and regulatory ubiquitylation events on distinct protein populations. Using a recently developed potent inhibitor of the critical protein homeostasis factor p97/VCP, we demonstrate that distinct insults to protein homeostasis function can elicit robust and largely unique alterations to the ub-modified proteome. Taken together, we demonstrate that proteomic approaches to monitor the ub-modified proteome can be used to evaluate global protein homeostasis and can be used to monitor distinct functional outcomes for spatially separated protein populations. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

The publication lapse of papers in Radiochemical and Radioanalytical Letters

International Nuclear Information System (INIS)

Braun, T.; Nagydiosi-Kocsis, Gy.

1982-01-01

The time needed for passing through journal editorial and publication processing has been examined for the papers published in Radiochemical and Radioanalytical Letters for the years 1969-1981. (author)

On the methodology of radiochemical neutron activation analysis of noble metals

International Nuclear Information System (INIS)

Chai, C.F.; Ma, S.L.; Mao, X.Y.; Liao, K.N.; Liu, W.C.

1986-01-01

Two different radiochemical procedures were developed: chelate ion resin exchange and amine solvent extraction. Two kinds of new Chinese chelate resins (NANKAI-3926 and BEI-5) and a new long-chain primary amine N 1923 were compared with Srafion NMRR and the tertiary amine N 235 in absorption performance of noble metals, respectively. Influences of various experimental conditions, e.g. sample digestion, acidity, equilibrium time, as well as elution of noble metals, on analytical sensitivity and chemical yield were discussed. Combining with neutron activation, the radiochemical separation procedures developed were used to determine the noble metal contents in the geological samples from Permina/Triassic boundary in South China. (author)

Scientific and technical conference. Problems and horizons of development of chemical and radiochemical control in nuclear energetics. Collection of summaries of reports

International Nuclear Information System (INIS)

2001-01-01

During scientific and technical conference on problems of development of chemical and radiochemical control in nuclear energetics following themes were considered: the problems of methodological and instrumental assurance of chemical and radiochemical control at working nuclear power plants and nuclear energetic units; modern conceptions of automation systems construction of chemical and radiochemical control on the basis of intellectual measuring channels; the ways of decision of generally system problems of organization and management of chemical and radiochemical control using computed technologies; the problems of certification of chemical and radiochemical methods of measuring in nuclear energetics [ru

Radiochemical analysis of the Bikini ashes

Energy Technology Data Exchange (ETDEWEB)

Ishibashi, M; Shigematsu, T; Ishida, T

1954-01-01

The following nuclides were detected in the Bikini ashes by radiochemical procedures: /sup 45/Ca, /sup 89/Sr, /sup 91/Y, /sup 95/Zr, /sup 103/Ru, /sup 144/Pr, and /sup 237/U. The ion-exchange method was used for analysis of contaminated rain water which fell on the Kyoto area on May 16, 1954 from which the presence of /sup 89/Sr, /sup 95/Zr, and /sup 140/Ba, was detected. Rare earths seemed also to be present.

Radiochemical schemes of obtaining 89Sr and 90Y radionuclides

International Nuclear Information System (INIS)

Usarov, Z. O.

2010-03-01

Key words: strontium-89, yttrium-90, extraction and extraction-chromatographic purification of radionuclides, radiopharmaceuticals. Subjects of research: strontium-89 and yttrium-90 radionuclides and their chloride forms. Purpose of work is developing of radiochemical technologies on obtaining of 89 Sr and 90 Y on the WWR-SM reactor with high radionuclide purity. Methods of research: extraction and extraction-chromatographic methods of radionuclides separation, beta- and gamma-spectrometric methods of activity measuring. The results obtained and their novelty: Were determined the conformity to laws of Y and Sr distribution in two-phase systems TBP-HNO 3 , TBP-NH 4 NO 3 , TBP-HCI, HDEHP-NO 3 , HDEHP-NH 4 NO 3 and HDEHP-HCI. Were determined the conformity to laws of Y and Sr distribution in systems with craun ethers DB-18K-6 and DTBDB-18K-6 from water solutions of HNO 3 . Radiochemical technologies on obtaining of 89 Sr and 90 Y radionuclides including radiochemical process of yttrium target with using the systems TBP-HNO 3 and HDEHP/Teflone were developed. Practical value: the radiochemical technology of obtaining 89 Sr with high radionuclide purity was developed. The method of preparation a chloride compound of 89 SrCl 2 which is used as a drug form for preparation of 89 Sr- 'Metastron' was developed. The relatively simple method of on the way obtaining 90 Y in the reactor with high radionuclidic purity that is useful for follow using in medical practice was offered. Degree of embed and economic effectivity: the developed technologies have approbation in manufacturing conditions in Radiopreparat Enterprise of INP AS RU and were offered for receiving of domestic preparations against of import foreign analogues. The statement about using the invention by obtained patent is attached to dissertation. Field of application: the received results will be introduced in manufacture at Radiopreparat Enterprise of INP AS RU for receiving of domestic preparations

Imaging Scanner Usage in Radiochemical Purity Test

International Nuclear Information System (INIS)

Norhafizah Othman; Yahaya Talib; Wan Hamirul Bahrin Wan Kamal

2011-01-01

Imaging Scanner model BIOSCAN AR-2000 has been used in the radiochemical purity test for the product of Mo-99/ Tc-99m generator. Result from this test was produced directly where the percentage of pertechnetate was calculated based on width peak area by thin layer chromatography. This paperwork will explain the function, procedure, calibration of the instrument and discussed the advantages compared to the previous method. (author)

Radiochemical problems of radiation chemical synthesis in n, γ-field of nuclear reactor

International Nuclear Information System (INIS)

Mironov, V.P.; Frejdus, N.V.; Bugaenko, L.T.; Kalyazin, E.P.; Petryaev, E.P.

1981-01-01

A wide applicability of products of radiation chemical synthesis (RCS), using n, γ-irradiation, is limited by possible contamination of the latter with long-lived radioactive isotopes of chemical elements included in the composition of the reagent and compounds syntesized (chemically non-separable radionuclides - CNR). A technique of the determination of the limit accumulation CNR on the basis of radiation chemical parameters of the synthesis (radiation-chemical yield, the dose rate absorbed, singleness of purpose of RCS etc.) and radiochemical parameters of formation and accumulation of CNR (radiochemical yields of CNR in the products of radiolysis, neutron fluence, the reagent purity etc.) is suggested. The radiochemical evaluation of CNR accumulation (tritium and carbon-14), formed at the expense of activation with neutrons of chemical elements of water and organic substances, consisting of hydrogen, carbon and oxygen has shown that at relatively low yields of final products (> or approximately 3 molecules/100 eV) no accumulation of radionuclides in concentrations reaching the average admissible concentration takes place [ru

Minicomputer system for radiochemical analysis by coincidence spectrometry

International Nuclear Information System (INIS)

Brauer, F.P.; Fager, J.E.

1979-01-01

Minicomputer-based coincidence analysis methods have been developed for use in performing radiochemical analysis by high-resolution x- and gamma-ray coincidence spectrometry. This paper describes the data-acquisition and analysis methods develolped for qualitative and quantitative analyses of coincidence spectrometric data. Data-acquisition capabilities include both direct multiparameter pulse-height analysis and buffered list-mode acquisition

Slifers revisited: a method for determining yields independent of radiochemical measurements

International Nuclear Information System (INIS)

Rambo, J.T.

1976-01-01

It would be very desirable if an independent method other than radiochemical measurement were available to determine the yields of low-yield events in the alluviums and tuffs of areas 2, 9, and 10 at the Nevada Test Site. The successful application of slifers to the measurement of yields from high-yield events suggests that under some conditions they may also be usable with low-yield events. This view is supported by the evidence discussed here, which is based on direct experience with slifer yield measurements for low-yield events in porous media. Suggested methods for improving slifer yield determinations and a method for determining yields independent of radiochemical measurements are offered

Rapid radiochemical separation of short-lived radionuclides in neutron-activated samples

International Nuclear Information System (INIS)

Fardy, J.

1985-11-01

Radiochemical separation procedures based on the removal of metal ions by columns of C 18 -bonded silica gel after selective complexation are examined and the simplicity of the method demonstrated by its application to determination of Mn, Cu and Zn in neutron-activated biological material from the following solutions (pH 0-10, sulphate concentration 0,18M and 1,44M SO 4 ): 8-hydroxyquinoline (oxine), ammonium pyrrolidinedithiocarbamate (APDC), cupferron (CUP), 1-(2-pyridylazo)-2-naphthol (PAN), 1-(2'-thiazolylazo)-2-naphthol (TAN), 4-(2-pyridylazo) resorcinol (PAR), diethylammonium diethyldithiocarbamate (DDC), potassium ethyl xanthate (PEX), acetylacetone (AcAc) or thenoyltrifluoracetone (TTA). The method is rapid and reliable and readily adaptable in all radiochemical laboratories

Statistical processing of technological and radiochemical data

International Nuclear Information System (INIS)

Lahodova, Zdena; Vonkova, Kateřina

2011-01-01

The project described in this article had two goals. The main goal was to compare technological and radiochemical data from two units of nuclear power plant. The other goal was to check the collection, organization and interpretation of routinely measured data. Monitoring of analytical and radiochemical data is a very valuable source of knowledge for some processes in the primary circuit. Exploratory analysis of one-dimensional data was performed to estimate location and variability and to find extreme values, data trends, distribution, autocorrelation etc. This process allowed for the cleaning and completion of raw data. Then multiple analyses such as multiple comparisons, multiple correlation, variance analysis, and so on were performed. Measured data was organized into a data matrix. The results and graphs such as Box plots, Mahalanobis distance, Biplot, Correlation, and Trend graphs are presented in this article as statistical analysis tools. Tables of data were replaced with graphs because graphs condense large amounts of information into easy-to-understand formats. The significant conclusion of this work is that the collection and comprehension of data is a very substantial part of statistical processing. With well-prepared and well-understood data, its accurate evaluation is possible. Cooperation between the technicians who collect data and the statistician who processes it is also very important. (author)

Radiochemical determination of zirconium by inductively coupled plasma mass spectrometry (ICPMS)

International Nuclear Information System (INIS)

Oliveira, Thiago C.; Oliveira, Arno Heeren de

2013-01-01

The zirconium isotope 93 Zr is a long-lived pure β-particle-emitting radionuclide thus occurring as one of the radionuclides found in nuclear reactors. It's produced from 235 U fission and from 92 Zr neutron activation. Due to its long half-life, 93 Zr is one of the interest radionuclides for assessment studies performance of waste storage or disposal. Measurement of 93 Zr is difficult owing to its trace level concentration and its low activity in nuclear wastes and further because its certified standards are not frequently available. The aim of this work was to apply a selective radiochemical separation methodology for 93 Zr determination in nuclear waste and analyze it by Inductively Coupled Plasma Mass Spectrometry (ICPMS). To set up the zirconium radiochemical separation procedure, a zirconium tracer solution was used in order to follow the zirconium behavior during the radiochemical separation. A tracer solution containing the main interferences, Ba, Co, Eu, Fe, Mn, Nb, Ni, Sr, and Y was used in order to verify the decontamination factor during separation process. The limit of detection of 0,039 ppb was obtained for zirconium standard solutions by ICPMS. Then, the protocol will be applied to low level waste (LLW) and intermediate level waste (ILW) from nuclear power plants. (author)

The use of robots for automation in the radiochemical laboratory

International Nuclear Information System (INIS)

Huddleston, J.

1988-01-01

The use of robotic systems for automated processes such as overnight operations, procedures involving radiation hazards in radiochemical laboratories is discussed. Particular reference is made to their use in analytical problems. Their flexibility is emphasised. (U.K.)

Competitive Protein Adsorption on Polysaccharide and Hyaluronate Modified Surfaces

Science.gov (United States)

Ombelli, Michela; Costello, Lauren; Postle, Corinne; Anantharaman, Vinod; Meng, Qing Cheng; Composto, Russell J.; Eckmann, David M.

2011-01-01

We measured adsorption of bovine serum albumin (BSA) and fibrinogen (Fg) onto six distinct bare and dextran- and hyaluronate-modified silicon surfaces created using two dextran grafting densities and three hyaluronic acid (HA) sodium salts derived from human umbilical cord, rooster comb and streptococcus zooepidemicus. Film thickness and surface morphology depended on HA molecular weight and concentration. BSA coverage was enhanced on surfaces upon competitive adsorption of BSA:Fg mixtures. Dextranization differentially reduced protein adsorption onto surfaces based on oxidation state. Hyaluronization was demonstrated to provide the greatest resistance to protein coverage, equivalent to that of the most resistant dextranized surface. Resistance to protein adsorption was independent of the type of hyaluronic acid utilized. With changing bulk protein concentration from 20 to 40 µg ml−1 for each species, Fg coverage on silicon increased by 4×, whereas both BSA and Fg adsorption on dextran and HA were far less dependent of protein bulk concentration. PMID:21623481

Hanford radiochemical site decommissioning demonstration program

International Nuclear Information System (INIS)

Nelson, D.C.

1971-01-01

A program is proposed for the innovation, development, and demonstration of technologies necessary to decommission the Hanford radiochemical plant area to the extent that the sites can have unrestricted public access. The five tasks selected for development and demonstration of restoration techniques were restoration of a burial ground, decommissioning of a separations plant, restoration of a separations plant waste interim storage tank farm, restoration of a liquid disposal area, and disposal of large contaminated equipment. Process development requirements are tabulated and discussed. A proposed schedule and estimated costs are given

Multilayer Choline Phosphate Molecule Modified Surface with Enhanced Cell Adhesion but Resistance to Protein Adsorption.

Science.gov (United States)

Chen, Xingyu; Yang, Ming; Liu, Botao; Li, Zhiqiang; Tan, Hong; Li, Jianshu

2017-08-22

Choline phosphate (CP), which is a new zwitterionic molecule, and has the reverse order of phosphate choline (PC) and could bind to the cell membrane though the unique CP-PC interaction. Here we modified a glass surface with multilayer CP molecules using surface-initiated atom-transfer radical polymerization (SI-ATRP) and the ring-opening method. Polymeric brushes of (dimethylamino)ethyl methacrylate (DMAEMA) were synthesized by SI-ATRP from the glass surface. Then the grafted PDMAEMA brushes were used to introduce CP groups to fabricate the multilayer CP molecule modified surface. The protein adsorption experiment and cell culture test were used to evaluate the biocompatibility of the modified surfaces by using human umbilical veinendothelial cells (HUVECs). The protein adsorption results demonstrated that the multilayer CP molecule decorated surface could prevent the adsorption of fibrinogen and serum protein. The adhesion and proliferation of cells were improved significantly on the multilayer CP molecule modified surface. Therefore, the biocompatibility of the material surface could be improved by the modified multilayer CP molecule, which exhibits great potential for biomedical applications, e.g., scaffolds in tissue engineering.

Abyssal sediment erosion from the Central Indian Basin: Evidence from radiochemical and radiolarian studies

Digital Repository Service at National Institute of Oceanography (India)

Banakar, V.K.; Gupta, S.M.; Padmavati, V.K.

) 167-173 167 Elsevier Science Publishers B.V., Amsterdam Letter Section Abyssal sediment erosion in the Central Indian Basin: Evidence from radiochemical and radiolarian studies V.K. Banakar, S.M. Gupta and V.K. Padmavathi National Institute... of Oceanography, Dona-Paula, Goa-403 004, India (Revision accepted September 17, 1990) ABSTRACT Banakar, V.K., Gupta, S.M. and Padmavathi, V.K., 1991. Abyssal sediment erosion from the Central Indian Basin: Evi- dence from radiochemical and radiolarian studies...

ESOL facility for the generation and radiochemical separation of short half-life fission products

International Nuclear Information System (INIS)

Gehrke, R.J.; Meikrantz, D.H.; Baker, J.D.; Anderl, R.A.; Novick, V.J.; Greenwood, R.C.

1988-01-01

A facility has been developed at the Idaho National Engineering Laboratory (INEL) for the generation and rapid radiochemical separation of short half-life mixed fission products. This facility, referred to as the Idaho Elemental Separation On Line (ESOL), consists of electro-plated sources of spontaneously fissioning 252 Cf with a helium jet transport arrangement to continuously deliver short half-life, mixed fission products to the radiochemistry laboratory for rapid, computer controlled, radiochemical separations. 18 refs., 13 figs

14th radiochemical conference. Booklet of abstracts

International Nuclear Information System (INIS)

2002-03-01

The contributions dealt with the following topics: Radionuclides in the environment, radioecology; Nuclear analytical methods; Chemistry of actinide and trans-actinide elements; Ionizing radiation in science, technology, and arts and cultural heritage preservation; Production and application of radionuclides; Separation methods, speciation; Chemistry of nuclear fuel cycle, radiochemical problems in nuclear waste management; and Nuclear methods in medicine, radiopharmaceuticals, and radiodiagnostics, labelled compounds. Of the verbal and poster presentation, 192 have been input to INIS. (P.A.)

Comparison of Zirconium Phosphonate-Modified Surfaces for Immobilizing Phosphopeptides and Phosphate-Tagged Proteins.

Science.gov (United States)

Forato, Florian; Liu, Hao; Benoit, Roland; Fayon, Franck; Charlier, Cathy; Fateh, Amina; Defontaine, Alain; Tellier, Charles; Talham, Daniel R; Queffélec, Clémence; Bujoli, Bruno

2016-06-07

Different routes for preparing zirconium phosphonate-modified surfaces for immobilizing biomolecular probes are compared. Two chemical-modification approaches were explored to form self-assembled monolayers on commercially available primary amine-functionalized slides, and the resulting surfaces were compared to well-characterized zirconium phosphonate monolayer-modified supports prepared using Langmuir-Blodgett methods. When using POCl3 as the amine phosphorylating agent followed by treatment with zirconyl chloride, the result was not a zirconium-phosphonate monolayer, as commonly assumed in the literature, but rather the process gives adsorbed zirconium oxide/hydroxide species and to a lower extent adsorbed zirconium phosphate and/or phosphonate. Reactions giving rise to these products were modeled in homogeneous-phase studies. Nevertheless, each of the three modified surfaces effectively immobilized phosphopeptides and phosphopeptide tags fused to an affinity protein. Unexpectedly, the zirconium oxide/hydroxide modified surface, formed by treating the amine-coated slides with POCl3/Zr(4+), afforded better immobilization of the peptides and proteins and efficient capture of their targets.

Thorium base fuels reprocessing at the L.P.R. (Radiochemical Processes Laboratory) experimental plant

International Nuclear Information System (INIS)

Almagro, J.C.; Dupetit, G.A.; Deandreis, R.A.

1987-01-01

The availability of the LPR (Radiochemical Processes Laboratory) plant offers the possibility to demonstrate and create the necessary technological basis for thorium fuels reprocessing. To this purpose, the solvents extraction technique is used, employing TBP (at 30%) as solvent. The process is named THOREX, a one-cycle acid, which permits an adequate separation of Th 232 and U 233 components and fission products. For thorium oxide elements dissolution, the 'chopp-leach' process (installed at LPR) is used, employing a NO 3 H 13N, 0.05M FH and 0.1M Al (NO 3 ) 3 , as solvent. To adapt the pilot plant to the flow-sheet requirements proposed, minor modifications must be carried out in the interconnection of the existing decanting mixers. The input of the plant has been calculated by Origin Code modified for irradiations in reactors of the HWR type. (Author)

DNA-modified electrodes fabricated using copper-free click chemistry for enhanced protein detection.

Science.gov (United States)

Furst, Ariel L; Hill, Michael G; Barton, Jacqueline K

2013-12-31

A method of DNA monolayer formation has been developed using copper-free click chemistry that yields enhanced surface homogeneity and enables variation in the amount of DNA assembled; extremely low-density DNA monolayers, with as little as 5% of the monolayer being DNA, have been formed. These DNA-modified electrodes (DMEs) were characterized visually, with AFM, and electrochemically, and were found to facilitate DNA-mediated reduction of a distally bound redox probe. These low-density monolayers were found to be more homogeneous than traditional thiol-modified DNA monolayers, with greater helix accessibility through an increased surface area-to-volume ratio. Protein binding efficiency of the transcriptional activator TATA-binding protein (TBP) was also investigated on these surfaces and compared to that on DNA monolayers formed with standard thiol-modified DNA. Our low-density monolayers were found to be extremely sensitive to TBP binding, with a signal decrease in excess of 75% for 150 nM protein. This protein was detectable at 4 nM, on the order of its dissociation constant, with our low-density monolayers. The improved DNA helix accessibility and sensitivity of our low-density DNA monolayers to TBP binding reflects the general utility of this method of DNA monolayer formation for DNA-based electrochemical sensor development.

Heterologous protein secretion in Lactobacilli with modified pSIP vectors.

Directory of Open Access Journals (Sweden)

Ingrid Lea Karlskås

Full Text Available We describe new variants of the modular pSIP-vectors for inducible gene expression and protein secretion in lactobacilli. The basic functionality of the pSIP system was tested in Lactobacillus strains representing 14 species using pSIP411, which harbors the broad-host-range Lactococcus lactis SH71rep replicon and a β-glucuronidase encoding reporter gene. In 10 species, the inducible gene expression system was functional. Based on these results, three pSIP vectors with different signal peptides were modified by replacing their narrow-host-range L. plantarum 256rep replicon with SH71rep and transformed into strains of five different species of Lactobacillus. All recombinant strains secreted the target protein NucA, albeit with varying production levels and secretion efficiencies. The Lp_3050 derived signal peptide generally resulted in the highest levels of secreted NucA. These modified pSIP vectors are useful tools for engineering a wide variety of Lactobacillus species.

Kit preparation of 153Sm-EDTMP and factors affecting radiochemical purity and stability

International Nuclear Information System (INIS)

Ferro-Flores, G.; Tendilla, J.I.; Lopez-Gomez, M.A.; Aguilar-Hernandez, F.; Gonzalez-Zavala, M.A.; Parades-Gutierrez, L.; Avila-Ramirez, E.

1996-01-01

A fast kit method was developed for the production of 153 Sm-EDTMP in two steps avoiding the use of nitric acid, evaporation and sterilization of the final solution by autoclave. Methods of analysis for the determination of chemical and radiochemical purity in the radiopharmaceutical solution were established. Factors affecting radiochemical purity and stability of the complex as the molar ratio of EDTMP/Sm, concentration of phosphate buffer and neutralization of EDTMP prior kit preparation were also analyzed. The use of this radiopharmaceutical in rabbits and patients showed selective skeletal uptake. (author). 5 refs., 4 figs., 3 tabs

Radiochemical procedures for determination of selected members of the uranium and thorium series

International Nuclear Information System (INIS)

Smithson, G.L.

1979-01-01

The radiochemical procedures contained in this manual are adaptations of those developed and published by many radiochemists. In many cases the identity of the originator is not clear and usually modifications in the original procedure have been made by subsequent workers. Nearly all of the basic radiochemical techniques and separations in use today were developed during the Manhattan Project and can be found in U.S.A.E.C. reports published from 1945 to 1953. This manual contains methods for the determination of Pb-210, Po-210; Ra-226, Ra-228, Th-228, Th-230 and Th-232. (auth)

Pepsin-Assisted Transglutaminase Modifi cation of Functional Properties of a Protein Isolate Obtained from Industrial Sunfl ower Meal

Directory of Open Access Journals (Sweden)

Petya Ivanova

2017-01-01

Full Text Available The utilization of industrial sunfl ower meal to produce protein-rich products for the food industry is an alternative approach for bett er and more effi cient use of this agricultural by-product. Sunfl ower meal proteins possess specifi c functional properties, which however need improvement to broaden their potential as supplements for delivering high-quality products for human nutrition. The aim of the study is to evaluate the combined infl uence of low-degree pepsin hydrolysis and transglutaminase (TG modifi cation on industrial sunfl ower meal protein isolate functionality at pH=2 to 10. Three TG-modifi ed pepsin hydrolysates with the degree of hydrolysis of 0.48, 0.71 and 1.72 % were produced and named TG-PH1, TG-PH2 and TG-PH3, respectively. All three TG-modifi ed pepsin hydrolysates exhibited improved solubility at pH between 3.5 and 5.5 as the highest was observed of TG-PH3 at protein isoelectric point (pI=4.5. Sunfl ower meal protein isolate and TG-modifi ed sunfl ower meal protein isolate had greater solubility than the three TG-modifi ed hydrolysates at pH7. Signifi cant improvement of foam making capacity (p<0.05 was achieved with all three TG-modifi ed pepsin hydrolysates in the entire pH area studied. Pepsin hydrolysis of the protein isolate with the three degrees of hydrolysis did not improve foam stability. Improved thermal stability was observed with TG-PH3 up to 80 °C compared to the protein isolate (pH=7. At 90 °C, TG modifi cation of the protein isolate alone resulted in the highest thermal stability. Pepsin hydrolysis followed by a treatment with TG could be used to produce sunfl ower protein isolates with improved solubility, foam making capacity and thermal stability for use in the food industry.

A modified FASP protocol for high-throughput preparation of protein samples for mass spectrometry.

Directory of Open Access Journals (Sweden)

Jeremy Potriquet

Full Text Available To facilitate high-throughput proteomic analyses we have developed a modified FASP protocol which improves the rate at which protein samples can be processed prior to mass spectrometry. Adapting the original FASP protocol to a 96-well format necessitates extended spin times for buffer exchange due to the low centrifugation speeds tolerated by these devices. However, by using 96-well plates with a more robust polyethersulfone molecular weight cutoff membrane, instead of the cellulose membranes typically used in these devices, we could use isopropanol as a wetting agent, decreasing spin times required for buffer exchange from an hour to 30 minutes. In a typical work flow used in our laboratory this equates to a reduction of 3 hours per plate, providing processing times similar to FASP for the processing of up to 96 samples per plate. To test whether our modified protocol produced similar results to FASP and other FASP-like protocols we compared the performance of our modified protocol to the original FASP and the more recently described eFASP and MStern-blot. We show that all FASP-like methods, including our modified protocol, display similar performance in terms of proteins identified and reproducibility. Our results show that our modified FASP protocol is an efficient method for the high-throughput processing of protein samples for mass spectral analysis.

Influence of Storage Temperature on Radiochemical Purity of 99mTc-Radiopharmaceuticals.

Science.gov (United States)

Uccelli, Licia; Boschi, Alessandra; Martini, Petra; Cittanti, Corrado; Bertelli, Stefania; Bortolotti, Doretta; Govoni, Elena; Lodi, Luca; Romani, Simona; Zaccaria, Samanta; Zappaterra, Elisa; Farina, Donatella; Rizzo, Carlotta; Giganti, Melchiore; Bartolomei, Mirco

2018-03-15

The influence of effective room temperature on the radiochemical purity of 99m Tc-radiopharmaceuticals was reported. This study was born from the observation that in the isolators used for the preparation of the 99m Tc-radiopharmaceuticals the temperatures can be higher than those reported in the commercial illustrative leaflets of the kits. This is due, in particular, to the small size of the work area, the presence of instruments for heating, the continuous activation of air filtration, in addition to the fact that the environment of the isolator used for the 99m Tc-radiopharmaceuticals preparation and storage is completely isolated and not conditioned. A total of 244 99m Tc-radiopharmaceutical preparations (seven different types) have been tested and the radiochemical purity was checked at the end of preparation and until the expiry time. Moreover, we found that the mean temperature into the isolator was significantly higher than 25 °C, the temperature, in general, required for the preparation and storage of 99m Tc-radiopharmaceuticals. Results confirmed the radiochemical stability of radiopharmaceutical products. However, as required in the field of quality assurance, the impact that different conditions than those required by the manufacturer on the radiopharmaceuticals quality have to be verified before human administration.

Synthesis and structural characterization of carboxyethylpyrrole-modified proteins: mediators of age-related macular degeneration.

Science.gov (United States)

Lu, Liang; Gu, Xiaorong; Hong, Li; Laird, James; Jaffe, Keeve; Choi, Jaewoo; Crabb, John; Salomon, Robert G

2009-11-01

Protein modifications in which the epsilon-amino group of lysyl residues is incorporated into a 2-(omega-carboxyethyl)pyrrole (CEP) are mediators of age-related macular degeneration (AMD). They promote both angiogenesis into the retina ('wet AMD') and geographic retinal atrophy ('dry AMD'). Blood levels of CEPs are biomarkers for clinical prognosis of the disease. To enable mechanistic studies of their role in promoting AMD, for example, through the activation of B- and T-cells, interaction with receptors, or binding with complement proteins, we developed an efficient synthesis of CEP derivatives, that is especially effective for proteins. The structures of tryptic peptides derived from CEP-modified proteins were also determined. A key finding is that 4,7-dioxoheptanoic acid 9-fluorenylmethyl ester reacts with primary amines to provide 9-fluorenylmethyl esters of CEP-modified proteins that can be deprotected in situ with 1,8-diazabicyclo[5.4.0]undec-7-ene without causing protein denaturation. The introduction of multiple CEP-modifications with a wide variety of CEP:protein ratios is readily achieved using this strategy.

The Northern Marshall Islands radiological survey: A quality control program for radiochemical and gamma spectroscopy analysis

International Nuclear Information System (INIS)

Kehl, S.R.; Mount, M.E.; Robison, W.L.

1995-09-01

From 1979 to 1989, approximately 25,000 Post Northern Marshall Islands Radiological Survey (PNMIRS) samples were collected, and over 71,400 radiochemical and gamma spectroscopy analyses were performed to establish the concentration of 90 Sr, 137 Cs, 241 Am, and plutonium isotopes in soil, vegetation, fish, and animals in the Northern Marshall Islands. While the Low Level Gamma Counting Facility (B379) in the Health and Ecological Assessment (HEA) division accounted for over 80% of all gamma spectroscopy analyses, approximately 4889 radiochemical and 5437 gamma spectroscopy analyses were performed on 4784 samples of soil, vegetation, terrestrial animal, and marine organisms by outside laboratories. Four laboratories were used by Lawrence Livermore National Laboratory (LLNL) to perform the radiochemical analyses: Thermo Analytical Norcal, Richmond, California (TMA); Nuclear Energy Services, North Carolina State University (NCSU); Laboratory of Radiation Ecology, University of Washington (LRE); and Health and Ecological Assessment (HEA) division, LLNL, Livermore, California. Additionally, LRE and NCSU were used to perform gamma spectroscopy analyses. The analytical precision and accuracy were monitored by including blind duplicates and natural matrix standards in each group of samples analyzed. On the basis of reported analytical values for duplicates and standards, 88% of the gamma and 87% of the radiochemical analyses in this survey were accepted. By laboratory, 93% of the radiochemical analyses by TMA; 88% of the gamma-ray spectrometry and 100% of the radiochemistry analyses by NCSU; 89% of the gamma spectroscopy and 87% of the radiochemistry analyses by LRE; and 90% of the radiochemistry analyses performed by HEA's radiochemistry department were accepted

Electrochemistry as a basis for radiochemical generator systems

International Nuclear Information System (INIS)

Bentley, G.E.; Steinkruger, F.J.; Wanek, P.M.

1984-01-01

Ion exchange and solvent extraction techniques have been used extensively as the basis for radiochemical generators exploiting the differences in absorption behavior between the parent nuclide and its useful daughter nuclide. Many parent/daughter pairs of nuclides have sufficiently different polarographic half wave potentials so that their electrochemical behavior may be exploited for rapid separation of the daughter from the parent with minimal contamination of the product with the parent isotope

Isolation of pronephros cells which endocytose chemically modified proteins in the rainbow trout

International Nuclear Information System (INIS)

Dannevig, B.H.; Berg, T.

1986-01-01

Modified serum albumin is cleared from the blood by kidney cells in salmonid fishes. The present study deals with isolation of cells from pronephros which endocytose formaldehyde-treated human serum albumin (fHSA). Radioactively labelled fHSA or dinitrophenyl-conjugated albumin (DNP-HSA) were injected intravenously into rainbow trouts. Pronephros cells, containing the endocytosed protein, were isolated and further separated by centrifugal elutriation and density-gradient centrifugation. Most of the radioactive protein was elutriated together with small cells. After centrifuging the cells through a Percoll density gradient, radioactive protein was located in cells recovered in the upper part of the gradient. In mammals, fHSA and other modified proteins are mainly taken up by sinusoidal endothelial cells in the liver via a scavenger receptor 0. Our results suggest that a comparable function in salmonids is located in a subpopulation of relatively small cells in kidney tissue, possibly sinusoidal lining cells. The separation techniques used seemed to be suitable for isolation of different populations of pronephros cells

Preparation of Modified Films with Protein from Grouper Fish

Science.gov (United States)

Tecante, A.; Granados-Navarrete, S.; Martínez-García, C.

2016-01-01

A protein concentrate (PC) was obtained from Grouper fish skin and it was used to prepare films with different amounts of sorbitol and glycerol as plasticizers. The best performing films regarding resistance were then modified with various concentrations of CaCl2, CaSO4 (calcium salts), and glucono-δ-lactone (GDL) with the purpose of improving their mechanical and barrier properties. These films were characterized by determining their mechanical properties and permeability to water vapor and oxygen. Formulations with 5% (w/v) protein and 75% sorbitol and 4% (w/v) protein with a mixture of 15% glycerol and 15% sorbitol produced adequate films. Calcium salts and GDL increased the tensile fracture stress but reduced the fracture strain and decreased water vapor permeability compared with control films. The films prepared represent an attractive alternative for being used as food packaging materials. PMID:27597950

Synthesis of [11C]PBR170, a novel imidazopyridine, for imaging the translocator protein with PET

International Nuclear Information System (INIS)

Bourdier, Thomas; Henderson, David; Fookes, Christopher J.R.; Lam, Peter; Mattner, Filomena; Fulham, Michael; Katsifis, Andrew

2014-01-01

The translocator protein (TSPO) ligand 2-(6,8-dichloro-2-(4-ethoxyphenyl)imidazo[1,2-a]pyridin-3-yl) –N-(2-fluoropyridin-3-yl)–N-methylacetamide (PBR170), is a novel imidazopyridineacetamide with high affinity (2.6 nm) and selectivity for the TSPO. The synthesis of [ 11 C]PBR170 was accomplished by N-methylation of the corresponding desmethyl precursor with [ 11 C]methyl iodide in the presence of sodium hydroxide in dimethylformamide. [ 11 C]PBR170 was produced in 30–45% radiochemical yield (decay-corrected, based on [ 11 C]methyl iodide) with a radiochemical purity >98% and a specific activity of 90–190 GBq/μmol after 35 min of synthesis time. - Highlights: • Radiosynthesis of a novel ligand PBR170 with carbon-11. • 30–45% radiochemical yield (decay-corrected, based on [ 11 C]methyl iodide). • Radiosynthesis and formulation achieved in 35 min. • High radiochemical purity (>98%) and specific activity (90–190 GBq/µmol). • High affinity and selectivity for the translocator protein (TSPO)

Potential allergenicity research of Cry1C protein from genetically modified rice.

Science.gov (United States)

Cao, Sishuo; He, Xiaoyun; Xu, Wentao; Luo, Yunbo; Ran, Wenjun; Liang, Lixing; Dai, Yunqing; Huang, Kunlun

2012-07-01

With the development of genetically modified crops, there has been a growing interest in available approaches to assess the potential allergenicity of novel gene products. We were not sure whether Cry1C could induce allergy. We examined the protein with three other proteins to determine the potential allergenicity of Cry1C protein from genetically modified rice. Female Brown Norway (BN) rats received 0.1 mg peanut agglutinin (PNA), 1mg potato acid phosphatase (PAP), 1mg ovalbumin (OVA) or 5 mg purified Cry1C protein dissolved in 1 mL water by daily gavage for 42 days to test potential allergenicity. Ten days after the last gavage, rats were orally challenged with antigens, and physiologic and immunologic responses were studied. In contrast to sensitization with PNA, PAP and OVA Cry1C protein did not induce antigen-specific IgG2a in BN rats. Cytokine expression, serum IgE and histamine levels and the number of eosinophils and mast cells in the blood of Cry1C group rats were comparable to the control group rats, which were treated with water alone. As Cry1C did not show any allergenicity, we make the following conclusion that the protein could be safety used in rice or other plants. Copyright © 2012 Elsevier Inc. All rights reserved.

Investigations of radiochemical methods for the platinum group metals for NAA

International Nuclear Information System (INIS)

Tredoux, M.

A radiochemical procedure for the determination of the platinum group metals and gold is outlined in this report. The sample is irradiated, treated with acids and passed through anion-exchange columns before being determined by gamma spectrometry

Devising of the method for the determination of small and very small amounts of cadmium in biological materials by radiochemical version of neutron activation analysis

International Nuclear Information System (INIS)

Dybczynski, R.; Samczynski, Z.

1996-01-01

The newly modified version of the method for the determination of cadmium in biological materials by radiochemical NAA based on selective post irradiation separation of Cd using ion exchange rasin Retardion 11A8 is presented. The conditions necessary for the selective retaining of Cd on the column exploiting both anionic and cationic ion exchange function of the resin have been discussed. Depending on the composition of the external solution, cadmium existing in the form of either anionic chloride complexes or cationic amine species is taken up by quaternary ammonium or carboxylate functional groups, respectively while accompanying elements are eluted. The elaborated method was further verified by determine Cd content in several certified biological reference materials using neutron activation analysis. The ion exchange separation procedure assures very high radiochemical purity of the cadmium fraction. Decontamination factors obtained for Mo, Sb, Na, Zn, Co, Sc amounted to 10 3 - 10 6 . Detection limit for Cd was 0.5 μg kg -1 . Analytical results show good agreement with the certified values. (author). 10 refs, 7 figs, 1 tab

Rapid, radiochemical-ligand binding assay for methotrexate

International Nuclear Information System (INIS)

Caston, J.D.

1976-01-01

A radiochemical ligand binding assay for methotrexate is provided. A binder factor comprising a partially purified dihydrofolic acid reductase preparation is employed. The binder factor is conveniently prepared by homogenizing a factor containing animal organ such as liver, and extracting with isotonic saline and ammonium sulfate. A binder cofactor, NADPH 2 , is also employed in the binding reaction. The procedure contemplates both direct and sequential assay techniques, and it is not interfered with by vast excesses of many natural folate derivatives. 12 claims, 6 drawing figures

Standardization of equations for radiochemical calculations

International Nuclear Information System (INIS)

Danahy, R.J.; Dugan, T.A.; Tomlinson, F.K.; Jones, H.W.

1994-01-01

In mid 1993, the Fernald Environmental Restoration Management Corporation (FERMCO), with USEPA approval implemented a project quality assurance plan containing performance-based specifications for radiochemical sample analyses conducted in support of the Fernald site remediation activities. FERMCO's initial approach to acquiring performance-based radioanalytical services was to provide limited guidance regarding equations for computation of the quantities required in each analysis report. It became evident that there was a significant divergence of opinion on how to compute some very basic radiochemical quantities. The use of a standardized set of equations was needed in order to ensure comparability of data from different laboratories. In a remediation project of this magnitude, use of multiple laboratories is a virtual necessity. Consequently comparability of data becomes an extremely important issue. A critical issue in the Remedial Investigation/Feasibility Study (RI/FS) phase of the dean up project is to avoid the occurrence of excessive false positive sample results. Such results could lead to unnecessary clean up and significant additional cost. This paper describes the specific formulas FERMCO is currently using to define such quantities as net sample count rate, sample radionuclide concentration, radiometric tracer and gravimetric carrier recovery. Equations have also been produced to define the uncertainty in each of the above quantities. Equations for the Total Propagated Uncertainty (TPU) and for a sample-specific Minimum Detectable Concentration (MDC) have also been specified. Generalized equations have been reformulated to address the specific conditions which apply to the analysis of FERMCO samples. In particular, FERMCO requires results which have been corrected for the radioactivity in the blank while in other instances, sample results without blank correction are required

A comparison of the radiochemical stability of different iodine-131 labelled metaiodobenzylguanidine formulations for therapeutic use

International Nuclear Information System (INIS)

Wafelman, A.R.; Beijnen, J.H.; Hoefnagel, C.A.; Maes, R.A.A.

1994-01-01

The results of a stability study of three commercially available formulations of [ 131 I]MIBG for therapeutic use and an unstabilized formulation, stored under various conditions, are presented. The stability was followed for 20 days. In all formulations tested, free [ 131 I]iodide, formed by radiolysis, was the most important radiochemical impurity. The pharmaceutical formulation with the largest amount of stabilizer was radiochemically - but not chemically -most stable. (author)

Investigation of quantitative separation of thorium, uranium, neptunium and plutonium from complex radiochemical mixtures

International Nuclear Information System (INIS)

Ushatskij, V.N.; Preobrazhenskaya, L.D.; Kolychev, V.B.; Gugel', E.S.

1979-01-01

Quantitative separation of actinides and their radiochemical purification with the aid of TBP with subsequent separation of thorium and quantitative separation of U, Np and Pu with the aid of D2EHPA have been studied. The method has been developed for quantitative extraction-chromatographic separation and radiochemical purification of nanogram amounts of U, Pu and microgram amounts of Th and Np from complex radiochemical mixtures containing both fragment radioisotopes and non-radioactive macrocomponents ( Fe,Al,Mg,Mn, Na and others). The method calls for application of one-extraction-chromatographic column with TBP and one column with D2EHPA. Thorium is separated at the first stage since it does not form complexes in a chloride solution during washing of the sorption column with 6. OM HCl. Npsup((4)) and Pusup((3)) required for separation are stabilized with the aid of hydrazine and hydroxylamine mixture. The yield of each of the above-cited actinide elements during the complete two-stage separation and at the stage of their separation varies within the range of 98.5-99.3%

Protein classification using modified n-grams and skip-grams.

Science.gov (United States)

Islam, S M Ashiqul; Heil, Benjamin J; Kearney, Christopher Michel; Baker, Erich J

2018-05-01

Classification by supervised machine learning greatly facilitates the annotation of protein characteristics from their primary sequence. However, the feature generation step in this process requires detailed knowledge of attributes used to classify the proteins. Lack of this knowledge risks the selection of irrelevant features, resulting in a faulty model. In this study, we introduce a supervised protein classification method with a novel means of automating the work-intensive feature generation step via a Natural Language Processing (NLP)-dependent model, using a modified combination of n-grams and skip-grams (m-NGSG). A meta-comparison of cross-validation accuracy with twelve training datasets from nine different published studies demonstrates a consistent increase in accuracy of m-NGSG when compared to contemporary classification and feature generation models. We expect this model to accelerate the classification of proteins from primary sequence data and increase the accessibility of protein characteristic prediction to a broader range of scientists. m-NGSG is freely available at Bitbucket: https://bitbucket.org/sm_islam/mngsg/src. A web server is available at watson.ecs.baylor.edu/ngsg. erich_baker@baylor.edu. Supplementary data are available at Bioinformatics online.

Agrobacterium-mediated transformation of modified antifreeze protein gene in strawberry

Directory of Open Access Journals (Sweden)

Srisulak Dheeranupattana

2005-07-01

Full Text Available The optimum condition for shoot regeneration from leaf explants of strawberry cultivar Tiogar was investigated. It was found that the best regeneration condition was MS medium containing N6-Benzyladenine (BA and 2,4-Dichlorophenoxy acetic acid (2,4-D at concentrations of 1 mg.l-1 and 0.2 mg.l-1, respectively. Antibiotics sensitivity test found that shoot regeneration from leaf explant was inhibited more than 90% at the concentration of kanamycin (Km as low as 5 mg.l-1. The modified gene encoding antifreeze protein isoform HPLC 6 was successfully constructed using codons which were optimally expressed in the strawberry plant. The antifreeze protein genes, naturally in plasmid pSW1 and modified in plasmid BB, were transformed to strawberry leaf explants by Agrobacterium tumefaciens LBA 4404. The strawberry plants, transformed with both AFP genes, were able to root in MS media containing 50 mg.l-1 Km, while no roots grew from nontransformed plant in this condition. Polymerase chain reaction indicated that the transgenes were integrated in the genome of transformants.

Preparation of Modified Films with Protein from Grouper Fish

Directory of Open Access Journals (Sweden)

M. A. Valdivia-López

2016-01-01

Full Text Available A protein concentrate (PC was obtained from Grouper fish skin and it was used to prepare films with different amounts of sorbitol and glycerol as plasticizers. The best performing films regarding resistance were then modified with various concentrations of CaCl2, CaSO4 (calcium salts, and glucono-δ-lactone (GDL with the purpose of improving their mechanical and barrier properties. These films were characterized by determining their mechanical properties and permeability to water vapor and oxygen. Formulations with 5% (w/v protein and 75% sorbitol and 4% (w/v protein with a mixture of 15% glycerol and 15% sorbitol produced adequate films. Calcium salts and GDL increased the tensile fracture stress but reduced the fracture strain and decreased water vapor permeability compared with control films. The films prepared represent an attractive alternative for being used as food packaging materials.

11th radiochemical conference

International Nuclear Information System (INIS)

Prasil, Z.

1987-01-01

The conference met in four sesions which discussed: Separation methods, Radioanalytical methods, Labelled compounds and Miscellaneous. The first session discussed extraction methods, ion exchange and chromatographic separation of radioisotopes. The second session heard papers on the application of these methods, e.g., in geochemistry, on the use of radioactive tracers in radiochemical analysis and the use of activation analysis in the determination of trace elements. The third session heard papers on the preparation of labelled organic compounds with isotopes 3 H, 14 C, radioiodine and 32 P, on the preparation of RIA kits and on the chemistry and radiopharmacology of technetium compounds. The other contributions which could not be heard in any of the three sessions discussed, e.g., the preparation of elements on the cyclotron and microtron, the production of a new 99m Tc-generator, the participation of the IAEA in processing low- and medium-level radioactive wastes, etc. (E.S.)

Effects of insecticidal crystal proteins (Cry proteins) produced by genetically modified maize (Bt maize) on the nematode Caenorhabditis elegans

International Nuclear Information System (INIS)

Höss, Sebastian; Menzel, Ralph; Gessler, Frank; Nguyen, Hang T.; Jehle, Johannes A.; Traunspurger, Walter

2013-01-01

The genetically modified maize MON89034 × MON88017 expresses different crystal (Cry) proteins with pesticidal activity against the European corn borer (Cry1.105; Cry2Ab2) and the Western corn root worm (Cry3Bb1). Non-target organisms, such as soil nematodes, might be exposed to the Cry proteins that enter the soil in course of crop growing. Therefore, the risk of those proteins for nematodes was assessed by testing their toxic effects on Caenorhabditis elegans. All three insecticidal Cry proteins showed dose-dependent inhibitory effects on C. elegans reproduction (EC50: 0.12–0.38 μmol L −1 ), however, at concentrations that were far above the expected soil concentrations. Moreover, a reduced toxicity was observed when Cry proteins were added jointly. A C. elegans mutant strain deficient for receptors for the nematicidal Cry5B was also resistant against Cry1.105 and Cry2Ab2, suggesting that these Cry proteins bound to the same or similar receptors as nematicidal Cry proteins and thereby affect the reproduction of C. elegans. -- Highlights: •Insecticidal Cry proteins dose-dependently inhibited the reproduction of C. elegans. •Mixture toxicity was lower than expected from concentration-additive single effects. •Genes for MAPK-defense-pathway were up-regulated in presence of Cry protein mixture. •Knock-out strains deficient for Cry5B-receptors showed lower susceptibility to insecticidal Cry proteins. •Toxicity of insecticidal Cry-proteins on C. elegans occurred at concentrations far above expected field concentrations. -- Insecticidal Cry proteins expressed by genetically modified maize act on nematodes via a similar mode of action as nematicidal Cry proteins, however, at concentrations far above expected soil levels

Use of ethyl-α-isonitrosoacetoacetate in the rapid estimation and radiochemical separation of gold

International Nuclear Information System (INIS)

Sawant, A.D.; Haldar, B.C.

1978-01-01

The use of ethyl-α-isonitrosoacetoacetate in the rapid estimation and radiochemical separation of gold is reported. As low as 5.00 mg of Au can be estimated with an accuracy better than 1%. Decontamination values against platinum metals and other metals usually associated with Au are greater than 10 5 . Isotopes and results are tabulated. The time required for radiochemical separation is around 20 min and the recovery of Au is better than 80%. γ-activities were measured with a single channel analyser and NaI(Tl) detector. β-activities were counted on a thin end-window type GM counter. (T.I.)

Brown pigment formation in heated sugar-protein mixed suspensions containing unmodified and peptically modified whey protein concentrates.

Science.gov (United States)

Rongsirikul, Narumol; Hongsprabhas, Parichat

2016-01-01

Commercial whey protein concentrate (WPC) was modified by heating the acidified protein suspensions (pH 2.0) at 80 °C for 30 min and treating with pepsin at 37 °C for 60 min. Prior to spray-drying, such modification did not change the molecular weights (MWs) of whey proteins determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After spray-drying the modified whey protein concentrate with trehalose excipient (MWPC-TH), it was found that the α-lactalbumin (α-La) was the major protein that was further hydrolyzed the most. The reconstituted MWPC-TH contained β-lactoglobulin (β-Lg) as the major protein and small molecular weight (MW) peptides of less than 6.5 kDa. The reconstituted MWPC-TH had higher NH2 group, Trolox equivalent antioxidant capacity (TEAC), lower exposed aromatic ring and thiol (SH) contents than did the commercial WPC. Kinetic studies revealed that the addition of MWPC-TH in fructose-glycine solution was able to reduce brown pigment formation in the mixtures heated at 80 to 95 °C by increasing the activation energy (Ea) of brown pigment formation due to the retardation of fluoresced advanced glycation end product (AGEs) formation. The addition of MWPC to reducing sugar-glycine/commercial WPC was also able to lower brown pigment formation in the sterilized (121 °C, 15 min) mixed suspensions containing 0.1 M reducing sugar and 0.5-1.0 % glycine and/or commercial (P < 0.05). It was demonstrated that the modification investigated in this study selectively hydrolyzed α-La and retained β-Lg for the production of antibrowning whey protein concentrate.

Radiochemical neutron activation analysis for trace elements of basic ingredients of pan

International Nuclear Information System (INIS)

Zaidi, J.H.; Arif, M.; Fatima, I; Qureshi, I.H.

2002-01-01

Extensive use of pan, by one-tenth of world's population, entails the evaluation of trace element contents in its ingredients. Radiochemical neutron activation analysis (RNAA) was developed and successfully employed to determine the concentration of 36 trace elements (essential, toxic and nonessential) in its four basic ingredients, leaf of betel pepper, betel nut, catechu and lime. The radiochemical separation methodology has significantly improved the detection limits of most of these elements due to suppression of Compton background. Base-line values of certain toxic and essential elements in these ingredients is provided. The daily intake of essential and toxic elements through pan was estimated and compared with the recommended values. The cumulative intake of Mn is four times higher than the recommended value and that of toxic elements is well below the tolerance limits. (author)

Identification of liver protein targets modified by tienilic acid metabolites using a two-dimensional Western blot-mass spectrometry approach

Science.gov (United States)

Methogo, Ruth Menque; Dansette, Patrick M.; Klarskov, Klaus

2007-12-01

A combined approach based on two-dimensional electrophoresis-immuno-blotting and nanoliquid chromatography coupled on-line with electrospray ionization mass spectrometry (nLC-MS/MS) was used to identify proteins modified by a reactive intermediate of tienilic acid (TA). Liver homogenates from rats exposed to TA were fractionated using ultra centrifugation; four fractions were obtained and subjected to 2D electrophoresis. Following transfer to PVDF membranes, modified proteins were visualized after India ink staining, using an anti-serum raised against TA and ECL detection. Immuno-reactive spots were localized on the PVDF membrane by superposition of the ECL image, protein spots of interest were excised, digested on the membrane with trypsin followed by nLC-MS/MS analysis and protein identification. A total of 15 proteins were identified as likely targets modified by a TA reactive metabolite. These include selenium binding protein 2, senescence marker protein SMP-30, adenosine kinase, Acy1 protein, adenosylhomocysteinase, capping protein (actin filament), protein disulfide isomerase, fumarylacetoacetase, arginase chain A, ketohexokinase, proteasome endopeptidase complex, triosephosphate isomerase, superoxide dismutase, dna-type molecular chaperone hsc73 and malate dehydrogenase.

The role of high performance liquid chromatography in radiochemical/radiopharmaceutical synthesis and quality assurance

International Nuclear Information System (INIS)

Boothe, T.E.; Emran, A.M.

1990-01-01

The usefulness of HPLC in all areas of radiopharmaceutics has been demonstrated in numerous laboratories, particularly in the development of in-house radiopharmaceuticals for SPECT and PET. HPLC continues to be a powerful tool in preparation and quality assurance (QA) as illustrated in such areas as chemical and radiochemical identification; product separation and isolation; preparative scale purification; and specific activity determination. A review of established HPLC techniques in radiopharmaceutics will be presented. Examples from the literature as well as newer applications will be used in an attempt to assess and define the present-day role of HPLC in the preparation of radiochemicals and radiopharmaceuticals with emphasis on QA

Diaphragms obtained by radiochemical grafting in PTFE

International Nuclear Information System (INIS)

Nenner, T.; Fahrasmane, A.

1984-01-01

Diaphragms for alkaline water electrolysis are prepared by radiochemical grafting of PTFE fabric with styrene, which is later on sulfonated, or with acrylic acid. The diaphragms obtained are mechanically resistant to potash at temperatures up to 200 0 C, but show some degrafting, which limits the lifetime. The sulfonated styrene group has been found to be more stable in electrolysis than the acrylic acid. In both cases, the incorporation of a cross-linking agent like divinyl benzene improves the lifetime of the diaphragms. Electrolysis during 500 hours at 120 0 C and 10 kAm 2 could be performed. (author)

Low temperature radio-chemical energy conversion processes

International Nuclear Information System (INIS)

Gomberg, H.J.

1986-01-01

This patent describes a radio-chemical method of converting radiated energy into chemical energy form comprising the steps of: (a) establishing a starting chemical compound in the liquid phase that chemically reacts endothermically to radiation and heat energy to produce a gaseous and a solid constituent of the compound, (b) irradiating the compound in its liquid phase free of solvents to chemically release therefrom in response to the radiation the gaseous and solid constituents, (c) physically separating the solid and gaseous phase constituents from the liquid, and (d) chemically processing the constituents to recover therefrom energy stored therein by the irradiation step (b)

Rapid radiochemical separation of zirconium-95 and niobium-95

International Nuclear Information System (INIS)

Downey, D.M.; McLaughlin, C.L.

1983-01-01

A rapid method for the quantitative separation of 95 Zr and 95 Nb has been developed. The method is based on the ion flotation of cationic zirconium complex ions with sodium lauryl sulfate (NaLS) from niobium which is masked with hydrogen peroxide. The separation was applied to mixtures of 95 Zr and 95 Nb initially in oxalic acid solution and quantitative recoveries of the radiochemically pure radioisotopes were obtained. (orig.)

Trace analysis measurements in high-purity aluminium by means of radiochemical neutron and proton activation analysis

International Nuclear Information System (INIS)

Egger, K.P.

1987-01-01

The aim of the study consisted in the development of efficient radiochemical composite processes and activation methods for the multi-element determination of traces within the lower ng range in high-purity aluminium. More than 50 elements were determined with the help of activation with reactor neutrons; the selective separation of matrix activity (adsorption with hydrated antimony pentoxide) led to a noticeable improvement of detectability, as compared with instrumental neutron activation analysis. Further improvements were achieved with the help of radiochemical group separations in ion exchangers or with the help of the selective separation of the pure beta-emitting elements. Over 20 elements up to high atomic numbers were determined by means of activating 13 MeV protons and 23 Me protons. In this connection, improvements of the detection limit by as a factor of 10 were achieved with radiochemical separation techniques, as compared with pure instrumental proton activation analysis. (RB) [de

Rapid radiochemical methods for preparation of sup(99m)Tc labelled compounds

International Nuclear Information System (INIS)

Narasimhan, D.V.S.; Banodkar, S.M.; Kothari, K.; Mani, R.S.

1981-01-01

Several inorganic and organic compounds incorporating sup( 99 m)Tc are being extensively used for imaging various body organs. The preparation of these sup( 99 m)Tc compounds with the necessary purity requirements is carried out by controlled reduction of sup( 99 m)Tc-pertechnetate using Sn(II) ions as the reducing agent followed by complexation with various active ingredients. The authors here present procedures developed at Radiopharmaceuticals Section of BARC for preparing sup( 99 m)Tc-diphosphonate, sup( 99 m)Tc-glucoheptonate, sup( 99 m)Tc-albumin microspheres and sup( 99 m)Tc-phytate with high radiochemical purity. The paper also describes procedures for the preparation of freeze-dried kits for single step preparation of these compounds. The paper also describes the authors' experience with various analytical procedures for the determination of radiochemical purity of these preparations. (author)

Radiochemical and biological control of metaiodobenzyl-guanidine (MIBG) labeled with 131I

International Nuclear Information System (INIS)

Barboza, M.R.F.F. de; Muramoto, E.; Colturato, M.T.; Silva Valente Goncalves, R. da; Pereira, N.P.S. de; Almeida, M.A.T.M. de; Silva, C.P.G. da.

1988-07-01

This study shows the standardization of the radiochemical control of MIBG - 131 I in eletrophoretic system and also the biological control in Wistar rat for a period of time, not longer than 60 minutes after tracer administration. (author) [pt

Critical evaluation of the determination of zirconium and hafnium by instrumental and radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Burger, Mario; Kraehenbuehl, Urs

1991-01-01

Neutron activation analysis (instrument or radiochemical) is suitable for the determination of zirconium and hafnium in samples of geochemical origin only when sufficient attention is paid to inter-fering nuclides. The size of the necessary correction for INAA depends on the composition of the sample; this problem is discussed. The radio-chemical technique which is recommended involves separation of the samples, precipitations and anion-exchange separation. Results are given for various standard reference materials and for meteorites. (author). 12 refs.; 1 fig.; 9 tabs

Analytical and radiochemical methods in the stability study of the MIBI-Sm

International Nuclear Information System (INIS)

Isaac, M.; Leyva, R.; Gamboa, R.; Turino, D.

1997-01-01

99mT c-MIBI is a radiopharmaceutical imaging agent useful for assessing myocardial perfusion. This paper presents the stability results obtained in the radiochemical purity and others parameters in the quality control of 5 batch during more than 2 years

OPERATIONAL EXPERIENCE: UPGRADED MPC AND A SYSTEMS FOR THE RADIOCHEMICAL PLANT OF THE SIBERIAN CHEMICAL COMBINE

International Nuclear Information System (INIS)

RODRIGUEZ, C.; GOLOSKOKOV, I.; FISHBONE, L.; GOODEY, K.; LOOMIS, M.; CRAIN, B. JR.; LARSEN, R.

2003-01-01

The success of reducing the risk of nuclear proliferation through physical protection and material control/accounting systems depends upon the development of an effective design that includes consideration of the objectives of the systems and the resources available to implement the design. Included among the objectives of the design are facility characterization, definition of threat, and identification of targets. When considering resources, the designer must consider funds available, rapid low-cost elements, technology elements, human resources, and the availability of resources to sustain operation of the end system. The Siberian Chemical Combine (SCC) is a multi-function nuclear facility located in the Tomsk region of Siberia, Russia. Beginning in 1996, SCC joined with the United States Department of Energy (US/DOE) Material Protection, Control, and Accounting (MPC and A) Program to develop and implement MPC and A upgrades for the Radiochemical, Chemical Metallurgical, Conversion, Uranium Enrichment, and Reactor Plants of the SCC. At the Radiochemical Plant the MPC and A design and implementation process has been largely completed for the Plutonium Storage Facility and related areas of the Radiochemical Plant. Design and implementation of upgrades for the Radiochemical Plant include rapid physical protection upgrades such as bricking up of doors and windows, and installation of security-hardened doors. Rapid material control and accounting upgrades include installation of modern balances and bar code equipment. Comprehensive MPC and A upgrades include the installation of access controls to sensitive areas of the Plant, alarm communication and display (AC and D) systems to detect and annunciate alarm conditions, closed circuit (CCTV) systems to assess alarm conditions, central and secondary alarm station upgrades that enable security forces to assess and respond to alarm conditions, material control and accounting upgrades that include upgraded physical

Radiochemical regularities of migration mobility of Chernobyl' discharge radionuclides

International Nuclear Information System (INIS)

Skorobogat'ko, E.P.; Rybalko, S.I.

1992-01-01

Data on the radionuclude (RN) migration in environment later the Chernobyl' accident are generalized. Introduction of fallout of the radioactive discharge into environment causes necessity to account and to study different factors of geochemical and physicochemical character determining further RN behaviour in the medium. For a well-founded forecast of the behaviour it is necessity to use a complex of radiochemical and physicochemical research, lying in the base of radiation monitoring of environment. 1 refs

Rapid radiochemical separation of zirconium-95 and niobium-95

Energy Technology Data Exchange (ETDEWEB)

Downey, D.M.; McLaughlin, C.L.

1983-01-01

A rapid method for the quantitative separation of /sup 95/Zr and /sup 95/Nb has been developed. The method is based on the ion flotation of cationic zirconium complex ions with sodium lauryl sulfate (NaLS) from niobium which is masked with hydrogen peroxide. The separation was applied to mixtures of /sup 95/Zr and /sup 95/Nb initially in oxalic acid solution and quantitative recoveries of the radiochemically pure radioisotopes were obtained.

Efficiency of Database Search for Identification of Mutated and Modified Proteins via Mass Spectrometry

OpenAIRE

Pevzner, Pavel A.; Mulyukov, Zufar; Dancik, Vlado; Tang, Chris L

2001-01-01

Although protein identification by matching tandem mass spectra (MS/MS) against protein databases is a widespread tool in mass spectrometry, the question about reliability of such searches remains open. Absence of rigorous significance scores in MS/MS database search makes it difficult to discard random database hits and may lead to erroneous protein identification, particularly in the case of mutated or post-translationally modified peptides. This problem is especially important for high-thr...

Ultratrace determination of platinum in biological materials via neutron activation and radiochemical separation

International Nuclear Information System (INIS)

Zeisler, R.; Greenberg, R.R.

1982-01-01

A neutron activation analysis scheme based upon a radiochemical separation of the activation products has been developed. The method utilizes the inherent sensitivity of the activation reaction 198 Pt(n,ν) 199 Pt and counting of the daughter nuclide 199 Au. This nuclide is radiochemically separated from interfering activities by homogeneous precipitation as elemental gold. The remaining interference of the secondary reaction 197 Au(n,ν) 198 Au(n,ν) 199 Au from gold in the samples is quantitatively assessed and corrected. During this process accurate gold concentrations in the samples are obtained at ultratrace levels. The analysis scheme is applied to gold and platinum determinations in biological Standard Reference Materials and human liver specimens. Gold and platinum are determined at concentrations of 5x10 - 11 g/g, and at higher levels. (author)

13th Radiochemical Conference. Booklet of Abstracts

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-04-01

The Conference included the following sessions: (i) Opening plenary presentations (6 contributions); (ii) Chemistry of natural radionuclides, discovery of radium and polonium (6 verbal presentations + 5 poster presentations); (iii) Radionuclides in the environment, radioecology (29 + 48); (iv) Activation analysis and other radioanalytical methods (36 + 49); (v) Ionizing radiation in science and technology (12 + 12); (vi) Chemistry of actinide and trans-actinide elements (11 + 14); (vii) Separation methods, speciation (18 + 41); (viii) Production and application of radionuclides (14 + 29); and (ix) Radiochemical problems in nuclear waste management (12 + 22). The majority of verbal presentations has been input to INIS, mostly in the form of the full authors` abstracts. (P.A.)

13th Radiochemical Conference. Booklet of Abstracts

International Nuclear Information System (INIS)

1998-04-01

The Conference included the following sessions: (i) Opening plenary presentations (6 contributions); (ii) Chemistry of natural radionuclides, discovery of radium and polonium (6 verbal presentations + 5 poster presentations); (iii) Radionuclides in the environment, radioecology (29 + 48); (iv) Activation analysis and other radioanalytical methods (36 + 49); (v) Ionizing radiation in science and technology (12 + 12); (vi) Chemistry of actinide and trans-actinide elements (11 + 14); (vii) Separation methods, speciation (18 + 41); (viii) Production and application of radionuclides (14 + 29); and (ix) Radiochemical problems in nuclear waste management (12 + 22). The majority of verbal presentations has been input to INIS, mostly in the form of the full authors' abstracts. (P.A.)

Mercury determination in geological samples using radiochemical separation

International Nuclear Information System (INIS)

Goncalves, Cristina; Favaro, Deborah I.T.

1997-01-01

In this work, a radiochemical procedure is presented to increase the neutron activation analysis sensitivity. After irradiation, geological reference materials - Buffalo River Sediment (BRS- - NIST SRM 2704), Lake Sediment (BCR - CRM 280) and GXR-5 (USGS - AEG) - were leached with aqua regia in a Parr bomb placed in a domestic microwave oven and then bismuth diethyl dithiocarbamate was used to pre concentrate mercury by solvent extraction. This procedure eliminates the interference from 279 keV Se-75 photopeak and background radiation from 511 keV Cu-64 photopeak. (author). 15 refs., 2 figs., 1 tab

Studies on some Indian paints for radiochemical plants

International Nuclear Information System (INIS)

Mahesh Kumar, V.V.; Srinivasan, R.; Natarajan, R.

1996-01-01

The choice of paints in areas subjected to contamination and radiation in nuclear installation need special attention. The types of generic coatings are examined with reference to these requirements. Among those examined, certain types of epoxy paints are found to be attractive for these applications. Samples of epoxy paints obtained from some Indian manufacturers are tested for their suitability. Decontaminability and radiation resistance properties are also evaluated with special reference to radiochemical plants. Important specifications for such applications are listed. This report summarizes the results of these studies. (author)

Growth of a manganese nodule from Peru Basin: a radiochemical anatomy

International Nuclear Information System (INIS)

Reyss, J.L.; Lemaitre, N.; Marchig, V.; Southon, J.R.; Nelson, D.E.; Vogel, J.S.

1985-01-01

Attempts have been made to study the entire growth history of a manganese nodule from the northern part of Peru Basin in the Pacific using radiochemical profiles of 230 Th/ 232 Th, 227 Th/ 230 Th and 10 Be/ 9 Be. Combined with the observations on Fe-Mn contents and textural variation, the radiochemical data indicate that the nodule grew more or less concentrically throughout most of its existence since it formed 1.5 my ago, receiving Mn from both bottom water and pore water. This condition appeared to have changed about 180 ky ago when the growth became asymmetric in that the top and bottom sides became fixed in their relative positions on the sea floor. Since then, the bottom side accreted with a fast rate of close to 200 mm/my, apparently fueled by the supply of diagenetically remobilized Mn in pore water from the sediment substrate. In the meantime, the topside accumulated at about 6 mm/my, a value which is in the normal range for deep-sea nodules having their Mn supplied from the hydrogenous source. (author)

A radio-high-performance liquid chromatography dual-flow cell gamma-detection system for on-line radiochemical purity and labeling efficiency determination

DEFF Research Database (Denmark)

Lindegren, S; Jensen, H; Jacobsson, L

2014-01-01

In this study, a method of determining radiochemical yield and radiochemical purity using radio-HPLC detection employing a dual-flow-cell system is evaluated. The dual-flow cell, consisting of a reference cell and an analytical cell, was constructed from two PEEK capillary coils to fit into the w...

Preparation, radiochemical purity control and stability of 99mTc-mertiatide (Mag-3)

International Nuclear Information System (INIS)

Van Hemert, F.J.; Schimmel, K.J.M.; Van Eck-Smit, B.L.F.; Van Lenthe, H.

2005-01-01

Scintigraphic image analysis of 99m Tc-mertiatide (Mag-3, mercaptoacetyltriglycine) clearance provides the determination of the blood flow, the tubular transit time and the excretion as well from both kidneys. Radiopharmaceutical routine recommends a radiochemical purity control before administration of the product to a patient. The main objective of this study is to develop a Mag-3 labeling procedure that fits better than the previous one in our daily routine production of radiopharmaceuticals. Increasing proportions of 99m Tc-Mag-3 were measured during the heating and cooling steps of the Mag-3 labeling procedure. High performance liquid chromatography (HPLC) analysis was used to confirm the results of a rapid radiochemical quality control assay on standard instant thin-layer chromatography-silica gel (ITLC-SG) paper. The reconstitution time takes 20-25 minutes from the harvest of pertechnetate to a ready-for-use calibrated patient syringe. The HPLC profile of 99m Tc-Mag-3 including its minor impurities remains unchanged for 24-48 hours after reconstitution. The application of a programmable Peltier-directed device for heating/cooling provides a better control of the temperature course. The procedure proposed fully meets the labeling criteria recommended by the supplier and can be performed with a minimum of attention within a time-span that we formerly needed for solely the radiochemical purity control assay. Moreover, 99m Tc-Mag-3 prepared in this way seems to be considerably more stable than mentioned in the manufacturer's instructions. (author)

Rapid and sensitive enzymatic-radiochemical assay for the determination of triglycerides

International Nuclear Information System (INIS)

Khoo, J.C.; Miller, E.; Goldberg, D.I.

1987-01-01

An enzymatic-radiochemical method suitable for the determination of triglyceride levels of cells in culture is described. The method is based on the enzymatic hydrolysis of triglycerides to free fatty acids which then complex with 63 Ni. The method is rapid, accurate, and inexpensive. The procedure extends the sensitivity of triglyceride measurement to as low as 0.25 nanomoles

Oxidatively Modified Proteins in the Serous Subtype of Ovarian Carcinoma

Directory of Open Access Journals (Sweden)

Sharifeh Mehrabi

2014-01-01

Full Text Available Serous subtype of ovarian cancer is considered to originate from fallopian epithelium mucosa that has been exposed to physiological changes resulting from ovulation. Ovulation influences an increased in inflammation of epithelial ovarian cells as results of constant exposure of cells to ROS. The imbalance between ROS and antioxidant capacities, as well as a disruption of redox signaling, causes a wide range of damage to DNA, proteins, and lipids. This study applied spectrophotometric, dinitrophenylhydrazone (DNPH assay, two-dimensional gel electrophoresis, and Western blot analyses to assess the levels of oxidatively modified proteins in 100 primary serous epithelial ovarian carcinoma and normal/surrounding tissues. These samples were obtained from 56 Caucasian and 44 African-American patients within the age range of 61±10 years. Analyses showed that the levels of reactive protein carbonyl groups increased as stages progressed to malignancy. Additionally, the levels of protein carbonyls in serous ovarian carcinoma among African Americans are 40% (P<0.05 higher relative to Caucasian at similar advanced stages. Results suggest that oxidative stress is involved in the modification of carbonyl protein groups, leading to increased aggressiveness of epithelial ovarian tumors and may contribute to the disease's invasiveness among African Americans.

The use of cuprous iodide as a precipitation matrix in the radiochemical determination of 131I in milk

International Nuclear Information System (INIS)

McCurdy, D.E.; Mellor, R.A.; Lambdin, R.W.; McLain, M.E. Jr.

1980-01-01

As a result of the implementation of the As Low As is Reasonably Achievable philosophy to the nuclear power industry, recent U.S. Nuclear Regulatory Commission requirements have prompted high sensitivity radiochemical analysis for the measurement of 131 I in milk. The most recognized and commonly employed technique incorporates costly palladium iodide as the final precipitate in the radiochemical purification of the iodine chemical species. The procedure presented in this paper outlines the many advantages of using cuprous iodide as the final precipitate. These include lower cost per analysis, consistent recoveries, better precipitate matrix and good self absorption characteristics. Typical lower limit of detection values and operating characteristics obtained for high sensitivity β-γ analysis as well as gas proportional counting and a comparison of radiochemical and Ge(Li) spectrometric results for environmental samples collected during a recent Chinese weapons fallout incident are presented. (author)

Chromatographic and traditional albumin isotherms on cellulose: a model for wound protein adsorption on modified cotton

Science.gov (United States)

Albumin is the most abundant protein found in healing wounds. Traditional and chromatogrpahic protein isotherms of albumin binding on modified cotton fibers are useful in understanding albumin binding to cellulose wound dressings. An important consideration in the design of cellulosic wound dressin...

III Scientific-technical conference. Problems and outlooks for development of chemical and radiochemical control in atomic energetics (Atomenergoanalytics-2005). Summaries of reports

International Nuclear Information System (INIS)

2005-01-01

Summaries of reports of the III Scientific-technical conference: Problems and outlooks for development of chemical and radiochemical control in atomic energetics (Atomenergoanalytics-2005) are presented. The conference performed 20-22 September, 2005, in Sosnovyj Bor. Problems of methodical, instrumental and metrological supply of chemical, radiochemical and radiometric control at active NPP and NPU, modern concepts of construction of automated systems of chemical and radiometric control in the atomic energetics, directions for the decision of questions in organization and conducting of chemical and radiochemical control of water-chemical regimes of NPP and NPU are discussed [ru

Mixing and sampling tests for Radiochemical Plant

International Nuclear Information System (INIS)

Ehinger, M.N.; Marfin, H.R.; Hunt, B.

1999-01-01

The paper describes results and test procedures used to evaluate uncertainly and basis effects introduced by the sampler systems of a radiochemical plant, and similar parameters associated with mixing. This report will concentrate on experiences at the Barnwell Nuclear Fuels Plant. Mixing and sampling tests can be conducted to establish the statistical parameters for those activities related to overall measurement uncertainties. Density measurements by state-of-the art, commercially availability equipment is the key to conducting those tests. Experience in the U.S. suggests the statistical contribution of mixing and sampling can be controlled to less than 0.01 % and with new equipment and new tests in operating facilities might be controlled to better accuracy [ru

Proceedings of the Tripartite Seminar on Nuclear Material Accounting and Control at Radiochemical Plants; Trudy trekhstoronnego seminara Uchet i kontrol' yadernykh materialov na radiokhimicheskikh ustanovkakh

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

The problems of creation and operation of nuclear materials (NM) control and accounting systems and their components at radiochemical plants were discussed in seminar during November 2-6 of 1998. There were 63 Russian and 25 foreign participants in seminar. The seminar programme includes following sessions and articles: the aspects of State NM control and accountancy; NM control and accounting in radiochemical plants and at separate stages of reprocessing of spent nuclear fuel and irradiated fuel elements of commercial reactors; NM control and accountancy in storage facilities of radiochemical plants; NM control and accounting computerization, material balance assessment, preparation of reports; qualitative and quantitative measurements in NM control and accounting at radiochemical plants destructive analysis techniques.

Quantitative analysis of modified proteins and their positional isomers by tandem mass spectrometry: human histone H4.

Science.gov (United States)

Pesavento, James J; Mizzen, Craig A; Kelleher, Neil L

2006-07-01

Here we show that fragment ion abundances from dissociation of ions created from mixtures of multiply modified histone H4 (11 kDa) or of N-terminal synthetic peptides (2 kDa) correspond to their respective intact ion abundances measured by Fourier transform mass spectrometry. Isomeric mixtures of modified forms of the same protein are resolved and quantitated with a precision of protein ions created by electrospray greatly easing many of the systematic biases that more strongly affect small peptides (e.g., differences in ionization efficiency and ion m/z values). The ion fragmentation methods validated here are directly extensible to intact human proteins to derive quantitative information on the highly related and often isomeric protein forms created by combinatorial arrays of posttranslational modifications.

Simple protein structure-sensitive chronopotentiometric analysis with dithiothreitol-modified Hg electrodes

Czech Academy of Sciences Publication Activity Database

Ostatná, Veronika; Černocká, Hana; Paleček, Emil

2012-01-01

Roč. 87, SI (2012), s. 84-88 ISSN 1567-5394 R&D Projects: GA AV ČR(CZ) KJB100040901; GA ČR(CZ) GAP301/11/2055; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : protein electroanalysis * DTT-modified electrodes * electrocatalysis Subject RIV: BO - Biophysics Impact factor: 3.947, year: 2012

A radiochemical analyses of metastudtite and leachates from spent fuel

International Nuclear Information System (INIS)

McNamara, Bruce K.; Hanson, Brady D.; Buck, Edgar C.; Soderquist, Chuck Z.

2004-01-01

Immersion of commercial spent nuclear fuel (CSNF) in deionized water produced two novel corrosion products after a two-year contact period. Another unexpected result was that suspensions of aggregates were observed to form at the air-water interface for each of five samples. These solids were characterized, by SEM and XRD to be nearly pure metastudtite (UO4-2H2O); while the corrosion present on the surface of the fuel itself was determined to be studtite (UO4-2H2O). The occurrence of the floating phase prompted a radiochemical analysis of these solids. This chemical analysis was a unique opportunity to study the relatively pure corrosion phase for incorporation of radionuclides. The analysis indicated that high concentration of 90Sr, 137Cs, 99Tc, and that lower concentrations 237Np, 238, 239Pu and 243, 244Cm had partitioned with the air-water interface aggregates. The concentrations of 241Am were two orders of magnitude lower than the expected inventory in the suspended solids. The radiochemical analyses of the several leachate samples provide preliminary solubility data for the hydrogen peroxide leaching of CSNF and these data are compared to leaching of the same fuel in J-13 and deionized waters. The extent of fuel dissolution in these media are discussed

Triphenyl phosphine oxide as a substoichiometric radiochemical reagent: Determination of thallium

International Nuclear Information System (INIS)

Reddy, P.C.; Polaiah, B.; Rangamannar, B.

1991-01-01

A rapid radiochemical method has been developed for the determination of microgram amounts of thallium based on the substoichiometric extraction of its ocmplex with triphenylphosphine oxide into benzene from 6 M sulphuric acid. 10-90 μg of thallium was determined with an average error of 2.06%. The effect of diverse metal ions on the extraction was studied. (orig.)

Radiochemical separation and alpha-spectrometric determination of Americium in different matrixes

International Nuclear Information System (INIS)

Radenkovic, M.; Joksic, J.; Paligoric, D.

2009-01-01

A method of separation and alpha-spectrometric determination of americium, developed in VINCA Institute of Nuclear Sciences is described in the paper. The procedure is convenient to be used for 241 Am determination in environmental matrixes as well as samples of human origin if a very small concentrations are expected, using 243 Am as a tracer for radiochemical yield recovery. (author) [sr

Determination of the radiochemical purity of phosphorus-32 and tritium-labeled diisopropylphosphorofluoridate (DFP)

International Nuclear Information System (INIS)

Christopher, R.E.; Sheppard, G.

1975-01-01

A method is described for the determination of the radiochemical purity of labeled diisopropylphosphorofluoridate (DFP), based on the irreversible inhibition reaction with the enzyme α-chymotrypsin. The nature of the impurities in commercially available 32 P- and 3 H-labeled DFP is discussed

Trace determination of uranium and thorium in biological samples by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Benedik, Ljudmila; Repinc, Urska; Byrne, Anthony R.; Stegnar, Peter

2002-01-01

Radiochemical neutron activation analysis (RNAA) is an excellent method for determining uranium and thorium; it offers unique possibilities for their ultratrace analysis using selective radiochemical separations. Regarding the favourably sensitive nuclear characteristics of uranium and of thorium with respect to RNAA, but the different half-lives of their induced nuclides, two different approaches were used. In the first approach uranium and thorium were determined separately via 239 U, 239 Np and 233 Pa. In the second approach these elements were 239 239 233 determined simultaneously in a single sample using U and/or Np and Pa. Isolation of induced nuclides was based on separation by extraction and/or anion exchange chromatography. Chemical yields were measured in each sample aliquot using added 235 U, 238 Np and 231 Pa radioisotopic tracers. (author)

Radiochemical syntheses further radiopharmaceuticals for positron emission tomography and new strategies for their production

CERN Document Server

Kilbourn, Michael R; Kilbourn, Michael R

2015-01-01

This book describes methods and procedures for preparing PET radiopharmaceuticals, and highlights new methods for conducting radiochemical reactions with carbon-11 (C11) and fluorine-18 (F18), which are two of the most commonly used radionuclides in positron emission tomography (PET) imaging.     Provides reliable methods for radiochemical syntheses and reactions, including all essential information to duplicate the procedure     Eliminates the time-consuming process of searching journal articles and extracting pertinent details from lengthy experimental sections or supporting information     Focuses on an emerging and important area for pharmaceutical and medical applications     Encompasses technical, regulatory, and application aspects     Includes solid-phase radiochemistry, transition-metal catalyzed radiochemistry, microfluidics, click chemistry, green radiochemistry and new strategies for radiopharmaceutical quality control.

RADCHEM - Radiochemical procedures for the determination of Sr, U, Pu, Am and Cm

Energy Technology Data Exchange (ETDEWEB)

Sidhu, R. [Inst. for Energy Technology (Norway)

2006-04-15

An accurate determination of radionuclides from various sources in the environment is essential for assessment of the potential hazards and suitable countermeasures both in case of accidents, authorised release and routine surveillance. Reliable radiochemical separation and detection techniques are needed for accurate determination of alpha and beta emitters. Rapid analytical methods are needed in case of an accident for early decision-making. The objective of this project has been to compare and evaluate radiochemical procedures used at Nordic laboratories for the determination of strontium, uranium, plutonium, americium and curium. To gather detailed information on the procedures in use, a questionnaire regarding various aspects of radionuclide determination was developed and distributed to all (sixteen) relevant laboratories in the Nordic countries. The response and the procedures used by each laboratory were then discussed between those who answered the questionnaire. This report summaries the findings and gives recommendation on suitable practice. (au)

RADCHEM - Radiochemical procedures for the determination of Sr, U, Pu, Am and Cm

International Nuclear Information System (INIS)

Sidhu, R.

2006-04-01

An accurate determination of radionuclides from various sources in the environment is essential for assessment of the potential hazards and suitable countermeasures both in case of accidents, authorised release and routine surveillance. Reliable radiochemical separation and detection techniques are needed for accurate determination of alpha and beta emitters. Rapid analytical methods are needed in case of an accident for early decision-making. The objective of this project has been to compare and evaluate radiochemical procedures used at Nordic laboratories for the determination of strontium, uranium, plutonium, americium and curium. To gather detailed information on the procedures in use, a questionnaire regarding various aspects of radionuclide determination was developed and distributed to all (sixteen) relevant laboratories in the Nordic countries. The response and the procedures used by each laboratory were then discussed between those who answered the questionnaire. This report summaries the findings and gives recommendation on suitable practice. (au)

An overview of the status of radiochemical analysis in Hungary

International Nuclear Information System (INIS)

Solymosi, J.; Toth, G.

1994-01-01

This overview covers the following activities at radioanalytical laboratories in Hungary: tracer techniques and their applications; some important new results; radioimmunoassay; x-ray emission analysis and x-ray fluorescence analysis, Moessbauer-spectroscopy and their applications in various fields of science and technology; neutron activation analysis; radiochemical analysis for nuclear power plant applications activities in various laboratories; nuclear environmental analysis (radioanalytical methods for the investigation of contamination by nuclear facilities). (N.T.) 1 fig.; 7 tabs

Use of reference materials for quality control of elemental analysis by neutron activation with radiochemical separation

International Nuclear Information System (INIS)

Woittiez, J.R.W.

1990-01-01

This paper describes the use of certified reference materials to monitor the long-term quality of radiochemical separations. The practical limitations which determine the actual design of the quality control are discussed. The hypothesis that the high yield of the radiochemical separation will be constant with time has been checked and validated for the elements Zn, Fe, Co, Cd, Mo and to a lesser extent for W and Th using NBS SRM 1577A, BCR CRM 274 and IAEA RM A-11. This validation could not be made for the elements Cr, Au, and Ag. Especially for Cr there is a serious lack of appropiate certified reference materials. (orig.)

Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

International Nuclear Information System (INIS)

Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B.

2017-01-01

The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, 3 H, 14 C, 55 Fe, 59 Ni, 63 Ni, 90 Sr, 93 Zr, 94 Nb, 99 Tc, 129 I, 235 U, 238 U, 238 Pu, 239 + 240 Pu, 241 Pu, 242 Pu, 241 Am, 242 Cm e 243 + 244 Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

Radiochemical aging of an epoxy network; Vieillissement radiochimique d'un reseau epoxyde

Energy Technology Data Exchange (ETDEWEB)

Devanne, Th

2003-05-01

This thesis is to give a better understanding of the radiochemical aging of a thermoset resin under gamma irradiation. The conditions of aging are gamma irradiation under air with a dose rate of 2 kGy/h at 120 C. The requested lifetime is four years, it means a dose of 70 MGy. The first step of this work was the choice of a resistive epoxy resin. This choice was made thanks to the literature data. The high glass transition temperature and the high amount of aromatic groups were the main criteria of the final choice. After this choice, thermal and mechanical properties were followed under thermal and radiochemical aging: i) under thermal aging, after 600 hours at 220 C, the glass transition temperature remained unchanged. But, from a mechanical point of view, properties at break dramatically decreased. This embrittlement was assigned to a critical oxidized layer. The thickness of this layer was estimated about 30 {mu}m. ii) the same kind of embrittlement was observed under radiochemical aging. Moreover, it appeared a decrease of the glass transition temperature when increasing the dose of irradiation. This indicates that the main degradation mechanism is chain scission under anaerobic atmosphere. We, then, proposed a mechanistic model associated with a kinetic model to predict the evolution of the glass transition temperature depending on the irradiation conditions. Parameters of the kinetic model were determined by solid NMR and ESR experiments. Comparison between experimental and calculated values at 120 C is satisfactory, a global good agreement was found. (author)

On the radiochemical purity of elementary 35S with high specific activity

International Nuclear Information System (INIS)

Todorovsky, D.S.; Kostadinov, K.N.; Efremova, Yu.N.

1979-01-01

Radiochemical composition and chemical changes with increasing storage time of benzene solutions and of solid species of elementary 35 S with high specific activity are studied. The dependence of the stability on the specific activity and the radioactive concentration is shown and some tentative limits are given for permissible storage periods. (author)

Improved mucoadhesion and cell uptake of chitosan and chitosan oligosaccharide surface-modified polymer nanoparticles for mucosal delivery of proteins.

Science.gov (United States)

Dyawanapelly, Sathish; Koli, Uday; Dharamdasani, Vimisha; Jain, Ratnesh; Dandekar, Prajakta

2016-08-01

The main aim of the present study was to compare mucoadhesion and cellular uptake efficiency of chitosan (CS) and chitosan oligosaccharide (COS) surface-modified polymer nanoparticles (NPs) for mucosal delivery of proteins. We have developed poly (D, L-lactide-co-glycolide) (PLGA) NPs, surface-modified COS-PLGA NPs and CS-PLGA NPs, by using double emulsion solvent evaporation method, for encapsulating bovine serum albumin (BSA) as a model protein. Surface modification of NPs was confirmed using physicochemical characterization methods such as particle size and zeta potential, SEM, TEM and FTIR analysis. Both surface-modified PLGA NPs displayed a slow release of protein compared to PLGA NPs. Furthermore, we have explored the mucoadhesive property of COS as a material for modifying the surface of polymeric NPs. During in vitro mucoadhesion test, positively charged COS-PLGA NPs and CS-PLGA NPs exhibited enhanced mucoadhesion, compared to negatively charged PLGA NPs. This interaction was anticipated to improve the cell interaction and uptake of NPs, which is an important requirement for mucosal delivery of proteins. All nanoformulations were found to be safe for cellular delivery when evaluated in A549 cells. Moreover, intracellular uptake behaviour of FITC-BSA loaded NPs was extensively investigated by confocal laser scanning microscopy and flow cytometry. As we hypothesized, positively charged COS-PLGA NPs and CS-PLGA NPs displayed enhanced intracellular uptake compared to negatively charged PLGA NPs. Our results demonstrated that CS- and COS-modified polymer NPs could be promising carriers for proteins, drugs and nucleic acids via nasal, oral, buccal, ocular and vaginal mucosal routes.

Protein arrangement on modified diamond-like carbon surfaces – An ARXPS study

Energy Technology Data Exchange (ETDEWEB)

Oosterbeek, Reece N., E-mail: reece.oosterbeek@auckland.ac.nz [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019 (New Zealand); Seal, Christopher K. [Light Metals Research Centre, The University of Auckland, Private Bag 92019 (New Zealand); Hyland, Margaret M. [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019 (New Zealand)

2014-12-01

Highlights: • DLC coatings were modified by Ar{sup +} ion sputtering and laser graphitisation. • The surface properties of the coatings were measured, and it was found that the above methods increased sp{sup 2} content and altered surface energy. • ARXPS was used to observe protein arrangement on the surface. • Polar CO/CN groups were seen to be segregated towards the interface, indicating they play an important role in bonding. • This segregation increased with increasing polar surface energy, indicating an increased net attraction between polar groups. - Abstract: Understanding the nature of the interface between a biomaterial implant and the biological fluid is an essential step towards creating improved implant materials. This study examined a diamond-like carbon coating biomaterial, the surface energy of which was modified by Ar{sup +} ion sputtering and laser graphitisation. The arrangement of proteins was analysed by angle resolved X-ray photoelectron spectroscopy, and the effects of the polar component of surface energy on this arrangement were observed. It was seen that polar groups (such as CN, CO) are more attracted to the coating surface due to the stronger polar interactions. This results in a segregation of these groups to the DLC–protein interface; at increasing takeoff angle (further from to DLC–protein interface) fewer of these polar groups are seen. Correspondingly, groups that interact mainly by dispersive forces (CC, CH) were found to increase in intensity as takeoff angle increased, indicating they are segregated away from the DLC–protein interface. The magnitude of the segregation was seen to increase with increasing polar surface energy, this was attributed to an increased net attraction between the solid surface and polar groups at higher polar surface energy (γ{sub S}{sup p})

Protein arrangement on modified diamond-like carbon surfaces – An ARXPS study

International Nuclear Information System (INIS)

Oosterbeek, Reece N.; Seal, Christopher K.; Hyland, Margaret M.

2014-01-01

Highlights: • DLC coatings were modified by Ar + ion sputtering and laser graphitisation. • The surface properties of the coatings were measured, and it was found that the above methods increased sp 2 content and altered surface energy. • ARXPS was used to observe protein arrangement on the surface. • Polar CO/CN groups were seen to be segregated towards the interface, indicating they play an important role in bonding. • This segregation increased with increasing polar surface energy, indicating an increased net attraction between polar groups. - Abstract: Understanding the nature of the interface between a biomaterial implant and the biological fluid is an essential step towards creating improved implant materials. This study examined a diamond-like carbon coating biomaterial, the surface energy of which was modified by Ar + ion sputtering and laser graphitisation. The arrangement of proteins was analysed by angle resolved X-ray photoelectron spectroscopy, and the effects of the polar component of surface energy on this arrangement were observed. It was seen that polar groups (such as CN, CO) are more attracted to the coating surface due to the stronger polar interactions. This results in a segregation of these groups to the DLC–protein interface; at increasing takeoff angle (further from to DLC–protein interface) fewer of these polar groups are seen. Correspondingly, groups that interact mainly by dispersive forces (CC, CH) were found to increase in intensity as takeoff angle increased, indicating they are segregated away from the DLC–protein interface. The magnitude of the segregation was seen to increase with increasing polar surface energy, this was attributed to an increased net attraction between the solid surface and polar groups at higher polar surface energy (γ S p )

Pyrenebutanoate as a dynamic protein modifier for fluorometric detection in capillary zone electrophoresis

Czech Academy of Sciences Publication Activity Database

Horká, Marie; Šlais, Karel

2002-01-01

Roč. 23, 7-8 (2002), s. 1090-1095 ISSN 0173-0835 R&D Projects: GA AV ČR IAA4031901 Institutional research plan: CEZ:AV0Z4031919 Keywords : pyrenebutanoate * dynamic protein modifier * CZE Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.325, year: 2002

Automation of column-based radiochemical separations. A comparison of fluidic, robotic, and hybrid architectures

Energy Technology Data Exchange (ETDEWEB)

Grate, J.W.; O' Hara, M.J.; Farawila, A.F.; Ozanich, R.M.; Owsley, S.L. [Pacific Northwest National Laboratory, Richland, WA (United States)

2011-07-01

Two automated systems have been developed to perform column-based radiochemical separation procedures. These new systems are compared with past fluidic column separation architectures, with emphasis on using disposable components so that no sample contacts any surface that any other sample has contacted, and setting up samples and columns in parallel for subsequent automated processing. In the first new approach, a general purpose liquid handling robot has been modified and programmed to perform anion exchange separations using 2 mL bed columns in 6 mL plastic disposable column bodies. In the second new approach, a fluidic system has been developed to deliver clean reagents through disposable manual valves to six disposable columns, with a mechanized fraction collector that positions one of four rows of six vials below the columns. The samples are delivered to each column via a manual 3-port disposable valve from disposable syringes. This second approach, a hybrid of fluidic and mechanized components, is a simpler more efficient approach for performing anion exchange procedures for the recovery and purification of plutonium from samples. The automation architectures described can also be adapted to column-based extraction chromatography separations. (orig.)

Self-decomposition of radiochemicals. Principles, control, observations and effects

International Nuclear Information System (INIS)

Evans, E.A.

1976-01-01

The aim of the booklet is to remind the established user of radiochemicals of the problems of self-decomposition and to inform those investigators who are new to the applications of radiotracers. The section headings are: introduction; radionuclides; mechanisms of decomposition; effects of temperature; control of decomposition; observations of self-decomposition (sections for compounds labelled with (a) carbon-14, (b) tritium, (c) phosphorus-32, (d) sulphur-35, (e) gamma- or X-ray emitting radionuclides, decomposition of labelled macromolecules); effects of impurities in radiotracer investigations; stability of labelled compounds during radiotracer studies. (U.K.)

Guiding Principles for Sustainable Existing Buildings: Radiochemical Processing Laboratory

Energy Technology Data Exchange (ETDEWEB)

Pope, Jason E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2013-11-11

In 2006, the United States (U.S.) Department of Energy (DOE) signed the Federal Leadership in High Performance and Sustainable Buildings Memorandum of Understanding (MOU), along with 21 other agencies. Pacific Northwest National Laboratory (PNNL) is exceeding this requirement and, currently, about 25 percent of its buildings are High Performance and Sustainable Buildings. The pages that follow document the Guiding Principles conformance effort for the Radiochemical Processing Laboratory (RPL) at PNNL. The RPL effort is part of continued progress toward a building inventory that is 100 percent compliant with the Guiding Principles.

A radiochemical technique for the determination of mercury in drinking water

International Nuclear Information System (INIS)

Ahmad, S.; Chaudhri, M.S.; Qureshi, I.H.

1982-01-01

A radiochemical method for the separation and determination of mercury in drinking water has been developed. The radionuclides of mercury formed after neutron irradiation of the sample were separated by liquid/liquid extraction using PAN and TBA mixture in chloroform from aqueous nitric acid medium. Quantitative extraction of mercury was achieved in a single step and the equilibrium was attained within five minutes. (orig.)

Serum lipids modify periodontal infection - C-reactive protein association.

Science.gov (United States)

Haro, Anniina; Saxlin, Tuomas; Suominen, Anna-Liisa; Ylöstalo, Pekka; Leiviskä, Jaana; Tervonen, Tellervo; Knuuttila, Matti

2012-09-01

To investigate whether low-grade inflammation-related factors such as serum low-density (LDL-C) and high-density lipoprotein cholesterol (HDL-C) modify the association between periodontal infection and C-reactive protein. This study was based on a subpopulation of the Health 2000 Survey, which consisted of dentate, non-diabetic, non-rheumatic subjects who were 30-49 years old (n = 2710). The extent of periodontal infection was measured by means of the number of teeth with periodontal pocket ≥4 mm and teeth with periodontal pocket ≥6 mm and systemic inflammation using high sensitive C-reactive protein. The extent of periodontal infection was associated with elevated levels of C-reactive protein among those subjects whose HDL-C value was below the median value of 1.3 mmol/l or LDL-C above the median value of 3.4 mmol/l. Among those with HDL-C ≥ 1.3 mmol/l or LDL-C ≤ 3.4 mmol/l, the association between periodontal infection and serum concentrations of C-reactive protein was practically non-existent. This study suggests that the relation of periodontal infection to the systemic inflammatory condition is more complicated than previously presumed. The findings of this study suggest that the possible systemic effect of periodontal infection is dependent on serum lipid composition. © 2012 John Wiley & Sons A/S.

Present status of radiochemical double β decay study (238U)

International Nuclear Information System (INIS)

Chevallier, A.; Chevallier, J.; Escoubes, B.; Schulz, N.; Sens, J.C.; Madic, C.; Maillard, C.

1989-01-01

The reasons for which the 238 U is a suitable candidate for the β β decay processes are explained. The strategy adopted for the radiochemical separation of the 234 U is given. A chemical system based on extraction chromatography is applied. The Pu IV breakthrough curves obtained at 40C during 238 Pu/ 238 U separation cycles are presented. A short description of the chromatographic facility is given. The solution adopted for the low background α spectrometer is explained

Radiochemical analysis of chlorine-36

International Nuclear Information System (INIS)

Rodriguez, M.; Pina, G.; Lara, E.

2006-01-01

The radioactive chlorine isotope, 36 Cl, decays with a half-life of 3x10 5 years by emitting a beta particle (98 %) and by electron capture. The aim of this paper is to propose a radiochemical separation method of 36 Cl from the other beta-gamma emitters present in low and medium radioactive wastes such as spent ion exchange resins and evaporator concentrates, that arise from Nuclear Power Plants and particularly in the wastes that come from decommissioning activities of graphite reactors, in order to provide data for 36 Cl inventory calculations. The separation method proposed is based on an oxidation technique where chlorine is trapped by NaOH. 36 Cl beta emissions are measured by liquid scintillation counting by the dual label technique in order to avoid the contamination produced by 14 C which is also trapped by NaOH and which is the main contaminant present in graphite samples. The sensitivity of this method is sufficient to achieve the needed thresholds for the radiological characterization of the radioactive materials to which this method can be applied. (author)

Collected radiochemical and geochemical procedures

Energy Technology Data Exchange (ETDEWEB)

Kleinberg, J [comp.

1990-05-01

This revision of LA-1721, 4th Ed., Collected Radiochemical Procedures, reflects the activities of two groups in the Isotope and Nuclear Chemistry Division of the Los Alamos National Laboratory: INC-11, Nuclear and radiochemistry; and INC-7, Isotope Geochemistry. The procedures fall into five categories: I. Separation of Radionuclides from Uranium, Fission-Product Solutions, and Nuclear Debris; II. Separation of Products from Irradiated Targets; III. Preparation of Samples for Mass Spectrometric Analysis; IV. Dissolution Procedures; and V. Geochemical Procedures. With one exception, the first category of procedures is ordered by the positions of the elements in the Periodic Table, with separate parts on the Representative Elements (the A groups); the d-Transition Elements (the B groups and the Transition Triads); and the Lanthanides (Rare Earths) and Actinides (the 4f- and 5f-Transition Elements). The members of Group IIIB-- scandium, yttrium, and lanthanum--are included with the lanthanides, elements they resemble closely in chemistry and with which they occur in nature. The procedures dealing with the isolation of products from irradiated targets are arranged by target element.

Leakage evaluation in the PCV (Primary Containment Vessel) using chemical and radiochemical data

International Nuclear Information System (INIS)

Maeda, Katsuji; Nagasawa, Katsumi

1998-01-01

Keeping the reliability of nuclear power plant operation, the primary coolant leakage in the PCV is strictly restricted by the Technical Specifications. It is very important to detect an indication of leakage and estimate the source of leakage to provide countermeasures. Usually the indication of leakage will be detected by increase of drain flow in the PCV sump. There are some possibilities of leakage sources in the PCV, such as reactor water, main steam, condensate, feedwater and closed cooling water. The leakage source contain different chemical and radiochemical species. This means that the leakage source can be presumed and detected by using chemical information from the PCV atmosphere and sump water. To detect the leakage indication and the source quickly and exactly, the PCV Leakage Detection Expert System has been developed. This paper describes how to evaluate the leakage indication and source in the PCV by using chemical and radiochemical data. (author)

O-GlcNAc-specific antibody CTD110.6 cross-reacts with N-GlcNAc2-modified proteins induced under glucose deprivation.

Directory of Open Access Journals (Sweden)

Takahiro Isono

Full Text Available Modification of serine and threonine residues in proteins by O-linked β-N-acetylglucosamine (O-GlcNAc glycosylation is a feature of many cellular responses to the nutritional state and to stress. O-GlcNAc modification is reversibly regulated by O-linked β-N-acetylglucosamine transferase (OGT and β-D-N-acetylglucosaminase (O-GlcNAcase. O-GlcNAc modification of proteins is dependent on the concentration of uridine 5'-diphospho-N-acetylglucosamine (UDP-GlcNAc, which is a substrate of OGT and is synthesized via the hexosamine biosynthetic pathway. Immunoblot analysis using the O-GlcNAc-specific antibody CTD110.6 has indicated that glucose deprivation increases protein O-GlcNAcylation in some cancer cells. The mechanism of this paradoxical phenomenon has remained unclear. Here we show that the increased glycosylation induced by glucose deprivation and detected by CTD110.6 antibodies is actually modification by N-GlcNAc(2, rather than by O-GlcNAc. We found that this induced glycosylation was not regulated by OGT and O-GlcNAcase, unlike typical O-GlcNAcylation, and it was inhibited by treatment with tunicamycin, an N-glycosylation inhibitor. Proteomics analysis showed that proteins modified by this induced glycosylation were N-GlcNAc(2-modified glycoproteins. Furthermore, CTD110.6 antibodies reacted with N-GlcNAc(2-modified glycoproteins produced by a yeast strain with a ts-mutant of ALG1 that could not add a mannose residue to dolichol-PP-GlcNAc(2. Our results demonstrated that N-GlcNAc(2-modified glycoproteins were induced under glucose deprivation and that they cross-reacted with the O-GlcNAc-specific antibody CTD110.6. We therefore propose that the glycosylation status of proteins previously classified as O-GlcNAc-modified proteins according to their reactivity with CTD110.6 antibodies must be re-examined. We also suggest that the repression of mature N-linked glycoproteins due to increased levels of N-GlcNAc(2-modified proteins is a newly

Computer aided piping layout design in radiochemical plants- an improved software package

International Nuclear Information System (INIS)

Raju, R.P.; Siddiqui, H.R.

1995-01-01

A software package was developed and it was successfully implemented for the piping layout design of the four process cells of the Kalpakkam Reprocessing Project. This paper discusses in detail all the improvements and modifications that are being carried out in the package so that it becomes more meaningful and useful for implementation for the forthcoming radiochemical plants

Facility Effluent Monitoring Plan for the 325 Radiochemical Processing Laboratory

International Nuclear Information System (INIS)

Shields, K.D.; Ballinger, M.Y.

1999-03-01

This Facility Effluent Monitoring Plan (FEMP) has been prepared for the 325 Building Radiochemical Processing Laboratory (RPL) at the Pacific Northwest National Laboratory (PNNL) to meet the requirements in DOE Order 5400.1, ''General Environmental Protection Programs.'' This FEMP has been prepared for the RPL primarily because it has a ''major'' (potential to emit >0.1 mrem/yr) emission point for radionuclide air emissions according to the annual National Emission Standards for Hazardous Air Pollutants (NESHAP) assessment performed. This section summarizes the airborne and liquid effluents and the inventory based NESHAP assessment for the facility. The complete monitoring plan includes characterization of effluent streams, monitoring/sampling design criteria, a description of the monitoring systems and sample analysis, and quality assurance requirements. The RPL at PNNL houses radiochemistry research, radioanalytical service, radiochemical process development, and hazardous and radioactive mixed waste treatment activities. The laboratories and specialized facilities enable work ranging from that with nonradioactive materials to work with picogram to kilogram quantities of fissionable materials and up to megacurie quantities of other radionuclides. The special facilities within the building include two shielded hot-cell areas that provide for process development or analytical chemistry work with highly radioactive materials and a waste treatment facility for processing hazardous, mixed radioactive, low-level radioactive, and transuranic wastes generated by PNNL activities

Facility Effluent Monitoring Plan for the 325 Radiochemical Processing Laboratory

Energy Technology Data Exchange (ETDEWEB)

Shields, K.D.; Ballinger, M.Y.

1999-04-02

This Facility Effluent Monitoring Plan (FEMP) has been prepared for the 325 Building Radiochemical Processing Laboratory (RPL) at the Pacific Northwest National Laboratory (PNNL) to meet the requirements in DOE Order 5400.1, ''General Environmental Protection Programs.'' This FEMP has been prepared for the RPL primarily because it has a ''major'' (potential to emit >0.1 mrem/yr) emission point for radionuclide air emissions according to the annual National Emission Standards for Hazardous Air Pollutants (NESHAP) assessment performed. This section summarizes the airborne and liquid effluents and the inventory based NESHAP assessment for the facility. The complete monitoring plan includes characterization of effluent streams, monitoring/sampling design criteria, a description of the monitoring systems and sample analysis, and quality assurance requirements. The RPL at PNNL houses radiochemistry research, radioanalytical service, radiochemical process development, and hazardous and radioactive mixed waste treatment activities. The laboratories and specialized facilities enable work ranging from that with nonradioactive materials to work with picogram to kilogram quantities of fissionable materials and up to megacurie quantities of other radionuclides. The special facilities within the building include two shielded hot-cell areas that provide for process development or analytical chemistry work with highly radioactive materials and a waste treatment facility for processing hazardous, mixed radioactive, low-level radioactive, and transuranic wastes generated by PNNL activities.

Safety decommissioning regulations of radiochemical objects - the problem, requires urgent decision

International Nuclear Information System (INIS)

Rovnyj, S.I.; Arsent'eva, N.V.; Emel'yanov, N.M.; Kolesnikov, V.N.

2001-01-01

The necessity of planning and pursuance of the measures on decommissioning of radiochemical industry is discussed. Technological processes were stopped more than in 30 buildings and constructions of the PO Mayak. The characteristics of the technological buildings to be decommissioned were treated in the context of building peculiarities, function, character and level of contamination. An acceptable variant for reactor decommissioning invites development of the standard-legal aspects [ru

Receptor Activity-modifying Protein-directed G Protein Signaling Specificity for the Calcitonin Gene-related Peptide Family of Receptors.

Science.gov (United States)

Weston, Cathryn; Winfield, Ian; Harris, Matthew; Hodgson, Rose; Shah, Archna; Dowell, Simon J; Mobarec, Juan Carlos; Woodlock, David A; Reynolds, Christopher A; Poyner, David R; Watkins, Harriet A; Ladds, Graham

2016-10-14

The calcitonin gene-related peptide (CGRP) family of G protein-coupled receptors (GPCRs) is formed through the association of the calcitonin receptor-like receptor (CLR) and one of three receptor activity-modifying proteins (RAMPs). Binding of one of the three peptide ligands, CGRP, adrenomedullin (AM), and intermedin/adrenomedullin 2 (AM2), is well known to result in a Gα s -mediated increase in cAMP. Here we used modified yeast strains that couple receptor activation to cell growth, via chimeric yeast/Gα subunits, and HEK-293 cells to characterize the effect of different RAMP and ligand combinations on this pathway. We not only demonstrate functional couplings to both Gα s and Gα q but also identify a Gα i component to CLR signaling in both yeast and HEK-293 cells, which is absent in HEK-293S cells. We show that the CGRP family of receptors displays both ligand- and RAMP-dependent signaling bias among the Gα s , Gα i , and Gα q/11 pathways. The results are discussed in the context of RAMP interactions probed through molecular modeling and molecular dynamics simulations of the RAMP-GPCR-G protein complexes. This study further highlights the importance of RAMPs to CLR pharmacology and to bias in general, as well as identifying the importance of choosing an appropriate model system for the study of GPCR pharmacology. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Requirement of radiochemical recovery determination for gross alpha and gross beta estimation in drinking water

International Nuclear Information System (INIS)

Raveendran, Nanda; Rao, D.D.; Hegde, A.G.

2010-01-01

Presence of radionuclides in drinking water which emits Alpha and Beta particles are the potential sources of internal exposure in drinking water. Gross alpha and gross beta determination in drinking water and packaged drinking water (PDW) as per BIS (Bureau of Indian standards) standards is discussed here. The methods have been tested to account for losses in the radiochemical procedures using radionuclides such as 137 Cs, 90 Sr, 226 Ra, 239 Pu, 243 Am, 232 U. The methods have also been validated in an IAEA proficiency test conducted during 2009. Monitoring of gross alpha and gross beta activity observed in drinking water/packaged drinking water from various states of India were within the limits set by BIS. Average radiochemical recoveries of 84% and 63% were obtained for gross α and gross β respectively. (author)

Protein arrangement on modified diamond-like carbon surfaces - An ARXPS study

Science.gov (United States)

Oosterbeek, Reece N.; Seal, Christopher K.; Hyland, Margaret M.

2014-12-01

Understanding the nature of the interface between a biomaterial implant and the biological fluid is an essential step towards creating improved implant materials. This study examined a diamond-like carbon coating biomaterial, the surface energy of which was modified by Ar+ ion sputtering and laser graphitisation. The arrangement of proteins was analysed by angle resolved X-ray photoelectron spectroscopy, and the effects of the polar component of surface energy on this arrangement were observed. It was seen that polar groups (such as CN, CO) are more attracted to the coating surface due to the stronger polar interactions. This results in a segregation of these groups to the DLC-protein interface; at increasing takeoff angle (further from to DLC-protein interface) fewer of these polar groups are seen. Correspondingly, groups that interact mainly by dispersive forces (CC, CH) were found to increase in intensity as takeoff angle increased, indicating they are segregated away from the DLC-protein interface. The magnitude of the segregation was seen to increase with increasing polar surface energy, this was attributed to an increased net attraction between the solid surface and polar groups at higher polar surface energy (γSp).

A combined simple bubbling method with high performance liquid chromatography purification strategy, higher radiochemical yield and purity and faster preparation of carbon-11-raclopride.

Science.gov (United States)

Huang, Huacheng; Ning, Yanli; Zhang, Bucheng; Lou, Cen

2015-01-01

Carbon-11-raclopride (¹¹C-R) is a positron-emitting radiotracer successfully used for the study of cognitive control and widely applied in PET imaging. A simple automated preparation of ¹¹C-R by using the reaction of carbon-(11)-methyl triflate (¹¹C-MeOTF) or ¹¹C-methyl iodide (¹¹C-MeI) with demethylraclopride is described. Specifically we used a simple setup applied an additional "U" reaction vessel for ¹¹C-MeOTf compared with ¹¹C-MeI and assessed the influence of several solvents and of the amount of the percussor for ¹¹C-methylation of demethylraclopride by the bubbling method. The reversal of retention order between product and its precursor has been achieved for ¹¹C-R, enabling collection of the purified ¹¹C-R by using the HPLC column after shorter retention time. By the improved radiosynthesis and purification strategy, ¹¹C-R could be prepared with higher radiochemical yield than that of the previous studies. The yield for ¹¹C-MeOTf was 76% and for ¹¹C-CH3I >26% and with better radiochemical purity (>99% based on both ¹¹C-MeOTf and ¹¹C-MeI) as compared to the previously obtained purity of ¹¹C-R using HPLC method with acetonitrile as a part of mobile phase. Furthermore, by using ethanol as the organic modifier, residual solvent analysis prior to human injection could be avoided and ¹¹C-R could be injected directly following simple dilution and sterile filtration. Improved radiosynthesis and HPLC purification in combination with ethanol containing eluent, extremely shortened the time for preparation of ¹¹C-R, gave a higher radiochemical yield and purity for ¹¹C-R and can be used for multiple and faster synthesis of ¹¹C-R and probably for other ¹¹C-labeled radiopharmaceuticals.

Determination of gold and platinum in biological materials by radiochemical neutron activation analysis using electrolytic separation of gold

International Nuclear Information System (INIS)

Reitz, B.; Heydorn, K.

1993-01-01

A new method is presented for the determination of Au and Pt in biological materials based on neutron activation analysis with radiochemical separation of gold. Separation of gold by electrolytic deposition on a niobium cathode ascertains thee highest radiochemical purity without any interference from calcium or other major elements. With 199 Au as indicator for platinum the gold content of the sample not only strongly affects the limit of detection, but also causes interference by double neutron capture. Replicate analyses of BCR Certified Reference Materials No. 184, 185 and 186 were carried out. (author) 18 refs.; 3 figs.; 2 tabs

The use of radiochemical analysis for detecting biotracers of food radioactive contamination in Cherkasy Region

International Nuclear Information System (INIS)

Matvyijenko, D.G.

2003-01-01

Stable biotracers of radioactive contamination according to the findings of analytical control of the foodstuffs was determined. The use of radiochemical analysis for determining the activity of the foodstuffs and water (Sr-90, Cs-137) was evaluated

Statistical analysis of radiochemical measurements of TRU radionuclides in REDC waste

International Nuclear Information System (INIS)

Beauchamp, J.; Downing, D.; Chapman, J.; Fedorov, V.; Nguyen, L.; Parks, C.; Schultz, F.; Yong, L.

1996-10-01

This report summarizes results of the study on the isotopic ratios of transuranium elements in waste from the Radiochemical Engineering Development Center actinide-processing streams. The knowledge of the isotopic ratios when combined with results of nondestructive assays, in particular with results of Active-Passive Neutron Examination Assay and Gamma Active Segmented Passive Assay, may lead to significant increase in precision of the determination of TRU elements contained in ORNL generated waste streams

Screening for Glycosylphosphatidylinositol-Modified Cell Wall Proteins in Pichia pastoris and Their Recombinant Expression on the Cell Surface

Science.gov (United States)

Zhang, Li; Liang, Shuli; Zhou, Xinying; Jin, Zi; Jiang, Fengchun; Han, Shuangyan; Zheng, Suiping

2013-01-01

Glycosylphosphatidylinositol (GPI)-anchored glycoproteins have various intrinsic functions in yeasts and different uses in vitro. In the present study, the genome of Pichia pastoris GS115 was screened for potential GPI-modified cell wall proteins. Fifty putative GPI-anchored proteins were selected on the basis of (i) the presence of a C-terminal GPI attachment signal sequence, (ii) the presence of an N-terminal signal sequence for secretion, and (iii) the absence of transmembrane domains in mature protein. The predicted GPI-anchored proteins were fused to an alpha-factor secretion signal as a substitute for their own N-terminal signal peptides and tagged with the chimeric reporters FLAG tag and mature Candida antarctica lipase B (CALB). The expression of fusion proteins on the cell surface of P. pastoris GS115 was determined by whole-cell flow cytometry and immunoblotting analysis of the cell wall extracts obtained by β-1,3-glucanase digestion. CALB displayed on the cell surface of P. pastoris GS115 with the predicted GPI-anchored proteins was examined on the basis of potential hydrolysis of p-nitrophenyl butyrate. Finally, 13 proteins were confirmed to be GPI-modified cell wall proteins in P. pastoris GS115, which can be used to display heterologous proteins on the yeast cell surface. PMID:23835174

A direct reading on-line flowrate meter for use in radiochemical plant

International Nuclear Information System (INIS)

Shah, B.V.; Kaimal, C.K.R.; Siddiqui, I.A.; Kumar, S.V.

1987-01-01

A device for measurement and remote direct reading display of the flowrates of streams in a radiochemical plant is described. The device is interposed in the measured stream and consists of a syphon pot with a specially developed attachment on the discharge line. Differential pressure switches are used to trigger a timer device at set levels in the pot and the time required for filling the pot during each cycle is measured and is used to compute and display the flowrate. The device is accurate and reliable and is simple to fabricate and install. It is maintenance-free since it has no moving parts. It is also suggested that a manometer with conductive contacts could be used in place of the d.p. switches. The background and various stages of development of the device are described. The operating data is tabulated and parameters required for plant applications are indicated in detail. A simple method to detect and correct for errors due to drift in d.p. switch setting is also outlined. Sketches of typical syphon pot, the schematic of the apparatus and suggested layout for application in radiochemical plant are also included. (author). 11 figures, 6 tables

Radiochemical determination of 210 Pb and 226Ra in petroleum sludges and scales

International Nuclear Information System (INIS)

Araujo, Andressa Arruda de

2005-01-01

The oil extraction and production, both onshore and offshore, can generate different types of residues, such as sludge, that is deposited in the water/oil separators, valves and storage tanks and scales, which form i the inner surface of ducts and equipment. Analyses already carried out through gamma spectrometry indicated the existence of high radioisotope concentration. However, radionuclides emitting low-energy gamma-rays, such as 210 Pb, are hardly detected by that technique. Consequently, there is a need to test alternative techniques to determine this and other radionuclides from the 238 U series. This work, therefore, focuses on the radiochemical determination of the concentration of 210 Pb, and 226 Ra in samples of sludge and scale from the oil processing stations of the UN-SEAL, a PETROBRAS unit responsible for the exploration and production of petroleum in Sergipe and Alagoas. The sludge and scale samples went through a preliminary process of extraction of oil, in order to separate the solid phase, where the largest fraction of the radioactivity is concentrated. After oil removal, the samples were digested using alkaline fusion as an option for dissolution. Finally, their activity concentration was determined for the samples of sludge and scales, using and alternative radiochemical method, which is based on ionic exchange. The activity concentration found for 210 Pb varied from 1,14 to 507,3 kBq kg -1 . The values for 226 Ra were higher, varying from 4,36 to 3.445 kBq kg -1 . The results for 226 Ra were then compared with the ones found for the same samples of sludge and scales using gamma spectrometry. The results of the comparison confirm the efficiency of the methodology used int hi work, that is, radiochemical determination by means of ionic exchange. (author)

Drug-binding ability of human serum albumin at children with chronic virus hepatitis radiochemical definition method

International Nuclear Information System (INIS)

Kim, A.A.; Dadakhanov, J.A.; Djuraeva, G.T.; Shukurov, B.V.; Mavlyanov, I.R.

2006-01-01

Full text: The chronic virus hepatitis produces numerous abnormalities of liver function. The viruses of B, C, D, F and G hepatitis possess the ability to cause chronically proceeding diseases. Earlier we have found that binding ability of serum albumin at patients with acute forms of virus hepatitis is authentically reduced in comparison with the given parameters of control group. At an acute virus hepatitis B with middle severity the reducing of binding ability of serum albumin was observed at 70 % of patients. At an acute virus hepatitis A the reduce of binding ability of serum albumin is less expressed than at acute virus hepatitis B. At of chronic virus intoxication in human organism there is a formation and accumulation of toxic compounds in the excessive concentrations, which are not inherent to a normal metabolism. One of universal mechanisms of reaction of an organism on the increasing concentration of metabolism products is formation of complexes of various compounds with blood plasma proteins. The formation in an organism of endo- and exotoxins excessive concentrations results in blocking the binding centers of albumin molecule that causes the change of its complexing ability. The purpose of the present research: investigation of binding ability of serum albumin with use of radiochemical method at children with a chronic virus hepatitis B and C. Materials and methods. Under clinical observation there were 52 children in the age from 3 till 14 years. From them at 32 the chronic virus hepatitis B was confirmed, at 20 chronic virus - hepatitis C. Etiological diagnostics was carried out by definition of specific markers of a hepatitis B and C method IFA and PCR. Binding ability of serum albumin was defined by radiochemical method with use of the tritium labeled no-spa (drotaverine hydrochloride). The control group consists from 10 conditionally health children of similar age. Results and their discussion. The results of investigation have shown, that at a

Radiochemical assay for determination of dihydropyrimidinase activity using reversed-phase high-performance liquid chromatography

NARCIS (Netherlands)

van Kuilenburg, A. B.; van Lenthe, H.; van Gennip, A. H.

1999-01-01

A radiochemical assay was developed to measure the activity of dihydropyrimidinase (DHP) in human liver homogenates. The method is based on the separation of radiolabeled dihydrouracil from N-carbamyl-beta-alanine by HPLC with on-line detection of radioactivity combined with detection of 14CO2 by

Functional relevance of G-protein-coupled-receptor-associated proteins, exemplified by receptor-activity-modifying proteins (RAMPs).

Science.gov (United States)

Fischer, J A; Muff, R; Born, W

2002-08-01

The calcitonin (CT) receptor (CTR) and the CTR-like receptor (CRLR) are close relatives within the type II family of G-protein-coupled receptors, demonstrating sequence identity of 50%. Unlike the interaction between CT and CTR, receptors for the related hormones and neuropeptides amylin, CT-gene-related peptide (CGRP) and adrenomedullin (AM) require one of three accessory receptor-activity-modifying proteins (RAMPs) for ligand recognition. An amylin/CGRP receptor is revealed when CTR is co-expressed with RAMP1. When complexed with RAMP3, CTR interacts with amylin alone. CRLR, initially classed as an orphan receptor, is a CGRP receptor when co-expressed with RAMP1. The same receptor is specific for AM in the presence of RAMP2. Together with human RAMP3, CRLR defines an AM receptor, and with mouse RAMP3 it is a low-affinity CGRP/AM receptor. CTR-RAMP1, antagonized preferentially by salmon CT-(8-32) and not by CGRP-(8-37), and CRLR-RAMP1, antagonized by CGRP-(8-37), are two CGRP receptor isotypes. Thus amylin and CGRP interact specifically with heterodimeric complexes between CTR and RAMP1 or RAMP3, and CGRP and AM interact with complexes between CRLR and RAMP1, RAMP2 or RAMP3.

Cleanout and decontamination of radiochemical hot cells

International Nuclear Information System (INIS)

Surma, J.E.; Holton, L.K. Jr.; Katayama, Y.B.; Gose, J.E.; Haun, F.E.; Dierks, R.D.

1990-01-01

The Pacific Northwest Laboratory is developing and employing advanced remote and contact technologies in cleaning out and decontaminating six radiochemical hot cells at Hanford under the Department of Energy's Surplus Facilities Management Program. The program is using a series of remote and contact decontamination techniques to reduce costs and to significantly lower radiation doses to workers. Refurbishment of the cover blocks above the air lock trench reduced radiation exposure in the air lock and cleanout and decontamination of an analytical cell achieved a reduction in radioactive contamination. Nuclear Regulatory Commission-approved Type B burial boxes are also being used to reduce waste disposal costs and radiation doses. PNL is currently decommissioning its pilot-scale radioactive liquid-fed ceramic melter. Special tools have been developed and are being used to accomplish the world's first such effort. 4 refs., 5 figs

Radiochemical Analysis Methodology for uranium Depletion Measurements

Energy Technology Data Exchange (ETDEWEB)

Scatena-Wachel DE

2007-01-09

This report provides sufficient material for a test sponsor with little or no radiochemistry background to understand and follow physics irradiation test program execution. Most irradiation test programs employ similar techniques and the general details provided here can be applied to the analysis of other irradiated sample types. Aspects of program management directly affecting analysis quality are also provided. This report is not an in-depth treatise on the vast field of radiochemical analysis techniques and related topics such as quality control. Instrumental technology is a very fast growing field and dramatic improvements are made each year, thus the instrumentation described in this report is no longer cutting edge technology. Much of the background material is still applicable and useful for the analysis of older experiments and also for subcontractors who still retain the older instrumentation.

International intercalibration as a method for control of radiochemical analyses

International Nuclear Information System (INIS)

Angelova, A.; Totseva, R.; Karaivanova, R.; Dandulova, Z.; Botsova, L.

1994-01-01

The participation of the Radioecology Section at the National Centre for Radiology and Radiation Protection (NCRRP) in the International Interlaboratory Comparison of radiochemical analyses organized by WHO is reported. The method of evaluating accuracy of the results from inter calibrations concerning radionuclide determination of environmental samples is outlined. The data from analysis of cesium 137, strontium 90 and radium 226 in milk, sediments, soil and seaweed made by 21 laboratories are presented. They show a good accuracy values of the results from NCRRP. 1 tab. 2 figs., 6 refs

Preparation of proton rich radionuclides in support of radiochemical analysis

International Nuclear Information System (INIS)

Jerome, Simon; Larijani, Cyrus; Parker, David

2012-01-01

The production of proton rich radionuclides supports a wide range of radiochemical analyses via radioactive yield tracers ( 95m Tc and 236 Pu). In recent years, NPL and the University of Birmingham cyclotron have collaborated to produce these, and other, radionuclides. - Highlights: ► In this paper we options for the production of Tc and Pu tracers. ► The irradiation and measurement of targets producing Tc-95 m and Pu-236 are described. ► Options for production are discussed. ► The results of this study and future work needed are described.

Determination of mercury in biologycal samples by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Suc, N.V.

1989-01-01

The radiochemical neutron activation analysis was applied to determine contents of mercury in biological samples. Samples were digested in mixing of H 2 SO 4 and HNO 3 acid. After extraction of mercury by Ni-Ditiodietylphosphoric acid in carbontetrachloride, mercury was back extracted by 5% KI solution. Contents of mercury from five samples of fish was determined by this method. The accuracy of the method was checked by comparing it with NBS standard samples and results are good agreement

Analysis of the radiochemical purity of 18F-FDG by HPLC

International Nuclear Information System (INIS)

Chen Liguang; Tang Anwu; He Shanzhen; Chen Yulong

2001-01-01

The radiochemical purity (RCP) of 18 F-FDG is analyzed by HPLC. Eighty-five percent acetonitrile is used as the eluting solution. Carbon hydrate column is used as separation column. The t R of 18 F - is 6.50 min and 18 F-FDG is 9.00 min. HPLC take less time and has higher sensitivity than TLC for the same sample at the same time. So HPLC excels TLC in analyzing RCP of 18 F-FDG

Radiochemical analyses of several spent fuel Approved Testing Materials

International Nuclear Information System (INIS)

Guenther, R.J.; Blahnik, D.E.; Wildung, N.J.

1994-09-01

Radiochemical characterization data are described for UO 2 and UO 2 plus 3 wt% Gd 2 O 3 commercial spent nuclear fuel taken from a series of Approved Testing Materials (ATMs). These full-length nuclear fuel rods include MLA091 of ATM-103, MKP070 of ATM-104, NBD095 and NBD131 of ATM-106, and ADN0206 of ATM-108. ATMs 103, 104, and 106 were all irradiated in the Calvert Cliffs Nuclear Power Plant (Reactor No.1), a pressurized-water reactor that used fuel fabricated by Combustion Engineering. ATM-108 was part of the same fuel bundle designed as ATM-105 and came from boiling-water reactor fuel fabricated by General Electric and irradiated in the Cooper Nuclear Power Plant. Rod average burnups and expected fission gas releases ranged from 2,400 to 3,700 GJ/kgM. (25 to 40 Mwd/kgM) and from less than 1% to greater than 10%, respectively, depending on the specific ATM. The radiochemical analyses included uranium and plutonium isotopes in the fuel, selected fission products in the fuel, fuel burnup, cesium and iodine on the inner surfaces of the cladding, 14 C in the fuel and cladding, and analyses of the gases released to the rod plenum. Supporting examinations such as fuel rod design and material descriptions, power histories, and gamma scans used for sectioning diagrams are also included. These ATMs were examined as part of the Materials Characterization Center Program conducted at Pacific Northwest Laboratory provide a source of well-characterized spent fuel for testing in support of the US Department of Energy Office of Civilian Radioactive Waste Management Program

Radiochemical purity of Mo and Tc solution obtained after irradiation and dissolution of Mo-100-enriched and ultra-high-purity natural Mo disks

Energy Technology Data Exchange (ETDEWEB)

Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States); Chemerisov, Sergey D. [Argonne National Lab. (ANL), Argonne, IL (United States); Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-09-01

Four irradiations of ultra-high-purity natural Mo targets and one irradiation using 97.4% Mo-100-enriched material were performed. The purpose of these irradiations was to determine whether the presence of Sn stabilizer in the H₂O₂ used for the dissolution of sintered Mo disks can affect the radiochemical purity of the final K₂MoO₄ in 5M KOH solution. Results from radiochemical purity tests performed using thin-layer paper chromatography show that even 2– 3× excess of Sn-stabilized H₂O₂ typically used for dissolution of sintered Mo disks did not affect the radiochemical purity of the final product.

Optimized Mitochondrial Targeting of Proteins Encoded by Modified mRNAs Rescues Cells Harboring Mutations in mtATP6

Directory of Open Access Journals (Sweden)

Randall Marcelo Chin

2018-03-01

Full Text Available Summary: Mitochondrial disease may be caused by mutations in the protein-coding genes of the mitochondrial genome. A promising strategy for treating such diseases is allotopic expression—the translation of wild-type copies of these proteins in the cytosol, with subsequent translocation into the mitochondria, resulting in rescue of mitochondrial function. In this paper, we develop an automated, quantitative, and unbiased screening platform to evaluate protein localization and mitochondrial morphology. This platform was used to compare 31 mitochondrial targeting sequences and 15 3′ UTRs in their ability to localize up to 9 allotopically expressed proteins to the mitochondria and their subsequent impact on mitochondrial morphology. Taking these two factors together, we synthesized chemically modified mRNAs that encode for an optimized allotopic expression construct for mtATP6. These mRNAs were able to functionally rescue a cell line harboring the 8993T > G point mutation in the mtATP6 gene. : Allotopic expression of proteins normally encoded by mtDNA is a promising therapy for mitochondrial disease. Chin et al. use an unbiased and high-content imaging-based screening platform to optimize allotopic expression. Modified mRNAs encoding for the optimized allotopic expression constructs rescued the respiration and growth of mtATP6-deficient cells. Keywords: mitochondria, mitochondrial disease, mRNA, modified mRNA, ATP6, allotopic expression, rare disease, gene therapy, screening, high content imaging

Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B., E-mail: rpgm@cdtn.br, E-mail: reisas@cdtn.br, E-mail: gfk@cdtn.br, E-mail: esct@cdtn.br, E-mail: tco@cdtn.br, E-mail: ama@cdtn.br, E-mail: francom@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-07-01

The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, {sup 3}H, {sup 14}C, {sup 55}Fe, {sup 59}Ni, {sup 63}Ni, {sup 90}Sr, {sup 93}Zr, {sup 94}Nb, {sup 99}Tc, {sup 129}I, {sup 235}U, {sup 238}U, {sup 238}Pu, {sup 239}+{sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 242}Cm e {sup 243}+{sup 244}Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

Some problems concenrning the use of automated radiochemical separation systems in destructive neutron activation analysis

International Nuclear Information System (INIS)

Nagy, L.G.; Toeroek, G.

1977-01-01

The present state of a long term program is reviewed. It was started to elaborate a remote controlled automated radiochemical processing system for the neutron activation analysis of biological materials. The system is based on wet ashing of the sample followed by reactive desorption of some volatile components. The distillation residue is passed through a series of columns filled with selective ion screening materials to remove the matrix activity. The solution is thus ''stripped'' from the interfering radioions, and it is processed to single-elements through group separations using ion-exchange chromatographic techniques. Some special problems concerning this system are treated. (a) General aspects of the construction of a (semi)automated radiochemical processing system are discussed. (b) Comparison is made between various technical realizations of the same basic concept. (c) Some problems concerning the ''reconstruction'' of an already published processing system are outlined. (T.G.)

Evaluation of different detection systems to determine the radiochemical purity of the technetium eluate and the radiopharmaceutical sestamibi

Energy Technology Data Exchange (ETDEWEB)

Santos, Poliane Angelo de L.; Andrade, Wellington G., E-mail: polianeangelo@gmail.com, E-mail: wandrade@cnen.gov.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Santos, Luiz Antonio P.; Lima, Fabiana Farias de, E-mail: luanps@uol.com.br, E-mail: fflima@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN/CNEN-PE), Recife, PE (Brazil)

2013-07-01

Since 2008 the Brazilian Health Surveillance Agency (ANVISA) has imposed some rules requiring that Nuclear Medicine Services (NMS) perform a minimum of tests with the radiopharmaceuticals before they are administered to their patients according to the Resolution n. 38 (RDC 38). Among the tests, the radiochemical purity is very important because the effectiveness for the use in vivo, and the fact radiochemical impurities may increase the radiation dose beyond to cause some damage in the diagnostic images. Radiochemical Purity is determined by ascendant chromatography technique and when it is used by NMS, the strips are analyzed in dose calibrator. Furthermore, the low activity on the strips can produce errors due to the low detection of this equipment type. Therefore, the aim of this paper is to compare different methods for determining the radiochemical purity of {sup 99m}Tc eluate and {sup 99m}Tc-MIBI radiopharmaceutical; gamma camera, and dose calibrator. The study was developed in three clinics in Recife-PE, and 15 analyses were performed to determine radiochemical purity of technetium eluate and {sup 99m}Tc-MIBI. For evaluating technetium eluate it was used Whatman® 3MM paper in 1cmx8cm strips. On the other hand, for analyzing MIBI radiopharmaceutical it was used 3 Whatman® 3MM paper strips and 3 with silica gel in 1cmx6.5cm format. According to the manufactures, an 1cm point from the base of the strip was labeled. It was dropped 50μ1 of sodium pertechnetate and {sup 99m}Tc-MIBI and, then, the strips were put in the glass tank, with solvent, according to the pharmacopoeia and inserts of the drug manufacturers. After the solvent front reached the end point, the strips were removed and allowed to dry. Firstly, the radioactivity count was made with a gamma camera. After that, the strips were cut in half (eluate) and in 2.5 cm from the base (MIBI) and measured with a dose calibrator. The results of the average radiochemical purity of the eluate in clinics A, B

Modifying a standard method allows simultaneous extraction of RNA and protein, enabling detection of enzymes in the rat retina with low expressions and protein levels.

Science.gov (United States)

Agardh, Elisabet; Gustavsson, Carin; Hagert, Per; Nilsson, Marie; Agardh, Carl-David

2006-02-01

The aim of the study was to evaluate messenger RNA and protein expression in limited amounts of tissue with low protein content. The Chomczynski method was used for simultaneous extraction of RNA, and protein was modified in the protein isolation step. Template mass and cycling time for the complementary DNA synthesis step of real-time reverse transcription-polymerase chain reaction (RT-PCR) for analysis of catalase, copper/zinc superoxide dismutase, manganese superoxide dismutase, the catalytic subunit of glutamylcysteine ligase, glutathione peroxidase 1, and the endogenous control cyclophilin B (CypB) were optimized before PCR. Polymerase chain reaction accuracy and efficacy were demonstrated by calculating the regression (R2) values of the separate amplification curves. Appropriate antibodies, blocking buffers, and running conditions were established for Western blot, and protein detection and multiplex assays with CypB were performed for each target. During the extraction procedure, the protein phase was dissolved in a modified washing buffer containing 0.1% sodium dodecyl sulfate, followed by ultrafiltration. Enzyme expression on real-time RT-PCR was accomplished with high reliability and reproducibility (R2, 0.990-0.999), and all enzymes except for glutathione peroxidase 1 were detectable in individual retinas on Western blot. Western blot multiplexing with CypB was possible for all targets. In conclusion, connecting gene expression directly to protein levels in the individual rat retina was possible by simultaneous extraction of RNA and protein. Real-time RT-PCR and Western blot allowed accurate detection of retinal protein expressions and levels.

Fully automated synthesis of 11C-acetate as tumor PET tracer by simple modified solid-phase extraction purification

International Nuclear Information System (INIS)

Tang, Xiaolan; Tang, Ganghua; Nie, Dahong

2013-01-01

Introduction: Automated synthesis of 11 C-acetate ( 11 C-AC) as the most commonly used radioactive fatty acid tracer is performed by a simple, rapid, and modified solid-phase extraction (SPE) purification. Methods: Automated synthesis of 11 C-AC was implemented by carboxylation reaction of MeMgBr on a polyethylene Teflon loop ring with 11 C-CO 2 , followed by acidic hydrolysis with acid and SCX cartridge, and purification on SCX, AG11A8 and C18 SPE cartridges using a commercially available 11 C-tracer synthesizer. Quality control test and animals positron emission tomography (PET) imaging were also carried out. Results: A high and reproducible decay-uncorrected radiochemical yield of (41.0±4.6)% (n=10) was obtained from 11 C-CO 2 within the whole synthesis time about 8 min. The radiochemical purity of 11 C-AC was over 95% by high-performance liquid chromatography (HPLC) analysis. Quality control test and PET imaging showed that 11 C-AC injection produced by the simple SPE procedure was safe and efficient, and was in agreement with the current Chinese radiopharmaceutical quality control guidelines. Conclusion: The novel, simple, and rapid method is readily adapted to the fully automated synthesis of 11 C-AC on several existing commercial synthesis module. The method can be used routinely to produce 11 C-AC for preclinical and clinical studies with PET imaging. - Highlights: • A fully automated synthesis of 11 C-acetate by simple modified solid-phase extraction purification has been developed. • Typical non-decay-corrected yields were (41.0±4.6)% (n=10) • Radiochemical purity was determined by radio-HPLC analysis on a C18 column using the gradient program, instead of expensive organic acid column or anion column. • QC testing (RCP>99%)

Application of the spectrometric and radiochemical techniques in analyzing environmental samples from the Bulgarian Black Sea region

International Nuclear Information System (INIS)

Veleva, B.S.; Mungov, G.; Galabov, N.; Kolarova, M.; Guenchev, T.

1999-01-01

Development of the appropriate methods and techniques for marine and atmospheric radioactivity measurements in the NIMH-BAS during the last 5 years is presented. Approaches for pre-concentration of the radionuclides from the atmosphere and sea water samples followed with reliable radiochemical methods for radionuclides separation and low level counting are discussed. Dissolved radiocesium concentrations measured in a period of time starting in 1993 show some decrease with years and spatial variations probably due to the hydrophysical features of the sampling sides - the lower measured concentrations during 1995 and 1998 correspond to the lower salinity. Application of the radiochemical separation of Plutonium, Thorium, 90 Sr and Americium on the samples from the Bulgarian Black Sea coastal region is reported. (author)

Improving the radiochemical purity determination of 123I-labeled metaiodobenzylguanidine

International Nuclear Information System (INIS)

Luciana Carvalheira; Paulo Bechara Dutra; Paula Fernandes de Aguiar

2014-01-01

The HPLC method originally applied at the Nuclear Engineering Institute (IEN) for the radiochemical purity determination of 123iodine labeled m-iodobenzylguanidine ( 123 I-mIBG) takes 18.5 min. The final product release also depends on this result, and to facilitate this stage, we aimed to decrease this analysis time. We also intended to use fewer toxic compounds, if feasible. The optimization approach used herein was a combination of factorial and mixture designs to study simultaneously the selected variables. Analysis time, resolution and chromatograms aspect were the measured responses. The qualitative analysis of these responses provided the best chromatographic separation conditions that were 52 mM KH 2 PO 4 in a solution of ethanol and water (1:1), applying a flow rate of 0.50 mL min -1 and C18 column (4.6 × 250 mm, 5 μm). These optimum conditions not only decreased the analysis time in 61 %, but also allowed the reduction of mobile phase toxicity. To assure reliable data, method validation was performed for these conditions. The method has proved its specificity, the detection limit found was 3.70 × 10 -4 MBq mL -1 and the quantification limit has corresponded to 1.11 × 10 -3 MBq mL -1 . Repeatability and intermediate precision has not exceeded 3 and 5 %, respectively, and the accuracy has matched the interval of 95-105 %. This new method has been routinely applied in the radiochemical purity determination of 123 I-mIBG at IEN. (author)

X-ray crystallographic analysis of adipocyte fatty acid binding protein (aP2) modified with 4-hydroxy-2-nonenal

Energy Technology Data Exchange (ETDEWEB)

Hellberg, Kristina; Grimsrud, Paul A.; Kruse, Andrew C.; Banaszak, Leonard J.; Ohlendorf, Douglas H.; Bernlohr, David A. (UMM)

2012-07-11

Fatty acid binding proteins (FABP) have been characterized as facilitating the intracellular solubilization and transport of long-chain fatty acyl carboxylates via noncovalent interactions. More recent work has shown that the adipocyte FABP is also covalently modified in vivo on Cys117 with 4-hydroxy-2-nonenal (4-HNE), a bioactive aldehyde linked to oxidative stress and inflammation. To evaluate 4-HNE binding and modification, the crystal structures of adipocyte FABP covalently and noncovalently bound to 4-HNE have been solved to 1.9 {angstrom} and 2.3 {angstrom} resolution, respectively. While the 4-HNE in the noncovalently modified protein is coordinated similarly to a carboxylate of a fatty acid, the covalent form show a novel coordination through a water molecule at the polar end of the lipid. Other defining features between the two structures with 4-HNE and previously solved structures of the protein include a peptide flip between residues Ala36 and Lys37 and the rotation of the side chain of Phe57 into its closed conformation. Representing the first structure of an endogenous target protein covalently modified by 4-HNE, these results define a new class of in vivo ligands for FABPs and extend their physiological substrates to include bioactive aldehydes.

Integration of carboxyl modified magnetic particles and aqueous two-phase extraction for selective separation of proteins.

Science.gov (United States)

Gai, Qingqing; Qu, Feng; Zhang, Tao; Zhang, Yukui

2011-07-15

Both of the magnetic particle adsorption and aqueous two-phase extraction (ATPE) were simple, fast and low-cost method for protein separation. Selective proteins adsorption by carboxyl modified magnetic particles was investigated according to protein isoelectric point, solution pH and ionic strength. Aqueous two-phase system of PEG/sulphate exhibited selective separation and extraction for proteins before and after magnetic adsorption. The two combination ways, magnetic adsorption followed by ATPE and ATPE followed by magnetic adsorption, for the separation of proteins mixture of lysozyme, bovine serum albumin, trypsin, cytochrome C and myloglobin were discussed and compared. The way of magnetic adsorption followed by ATPE was also applied to human serum separation. Copyright © 2011 Elsevier B.V. All rights reserved.

HPLC-ICP-MS compared with radiochemical detection for metabolite profiling of H-3-bromohexine in rat urine and faeces

DEFF Research Database (Denmark)

Jensen, B.P.; Gammelgaard, B.; Hansen, S.H.

2005-01-01

H-3-Bromohexine was dosed to rats as a model compound to allow comparison of HPLC-ICP-MS detection on bromine to radiochemical detection in an in vivo drug metabolism study. Metabolite profiles were obtained in urine and faeces extracts. No influence of the methanol gradient on the bromine response...... was observed in the range of 18 - 75% methanol. The sensitivity obtained by HPLC- ICP-MS was almost two orders of magnitude better than on-line H-3 radiochemical detection. For ICP- MS, the limit of detection was calculated to be 69 nM Br ( injection volume 100 mu l), corresponding to an absolute limit...

Protein adsorption resistance of PVP-modified polyurethane film prepared by surface-initiated atom transfer radical polymerization

International Nuclear Information System (INIS)

Yuan, Huihui; Qian, Bin; Zhang, Wei; Lan, Minbo

2016-01-01

Highlights: • Antifouling PVP brushes were successfully grafted on PU films by SI-ATRP. • The effect of polymerization time on surface property and topography was studied. • Hydrophilicity and protein fouling resistance of PVP–PU films were greatly promoted. • Competitive adsorption of three proteins on PVP–PU films was evaluated. - Abstract: An anti-fouling surface of polyurethane (PU) film grafted with Poly(N-vinylpyrrolidone) (PVP) was prepared through surface-initiated atom transfer radical polymerization (SI-ATRP). And the polymerization time was investigated to obtain PU films with PVP brushes of different lengths. The surface properties and protein adsorption of modified PU films were evaluated. The results showed that the hydrophilicity of PU–PVP films were improved with the increase of polymerization time, which was not positive correlation with the surface roughness due to the brush structure. Additionally, the protein resistance performance was promoted when prolonging the polymerization time. The best antifouling PU–PVP (6.0 h) film reduced the adsoption level of bovine serum albumin (BSA), lysozyme (LYS), and brovin serum fibrinogen (BFG) by 93.4%, 68.3%, 85.6%, respectively, compared to the unmodified PU film. The competitive adsorption of three proteins indicated that LYS preferentially adsorbed on the modified PU film, while BFG had the lowest adsorption selectivity. And the amount of BFG on PU–PVP (6.0 h) film reduced greatly to 0.08 μg/cm"2, which was almost one-tenth of its adsorption from the single-protein system. Presented results suggested that both hydrophilicity and surface roughness might be the important factors in all cases of protein adsorption, and the competitive or selective adsorption might be related to the size of the proteins, especially on the non-charged films.

Protein adsorption resistance of PVP-modified polyurethane film prepared by surface-initiated atom transfer radical polymerization

Energy Technology Data Exchange (ETDEWEB)

Yuan, Huihui; Qian, Bin; Zhang, Wei [Shanghai Key Laboratory of Functional Materials Chemistry and Research Center of Analysis and Test, East China University of Science and Technology, Shanghai 200237 (China); Lan, Minbo, E-mail: minbolan@ecust.edu.cn [Shanghai Key Laboratory of Functional Materials Chemistry and Research Center of Analysis and Test, East China University of Science and Technology, Shanghai 200237 (China); State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237 (China)

2016-02-15

Highlights: • Antifouling PVP brushes were successfully grafted on PU films by SI-ATRP. • The effect of polymerization time on surface property and topography was studied. • Hydrophilicity and protein fouling resistance of PVP–PU films were greatly promoted. • Competitive adsorption of three proteins on PVP–PU films was evaluated. - Abstract: An anti-fouling surface of polyurethane (PU) film grafted with Poly(N-vinylpyrrolidone) (PVP) was prepared through surface-initiated atom transfer radical polymerization (SI-ATRP). And the polymerization time was investigated to obtain PU films with PVP brushes of different lengths. The surface properties and protein adsorption of modified PU films were evaluated. The results showed that the hydrophilicity of PU–PVP films were improved with the increase of polymerization time, which was not positive correlation with the surface roughness due to the brush structure. Additionally, the protein resistance performance was promoted when prolonging the polymerization time. The best antifouling PU–PVP (6.0 h) film reduced the adsoption level of bovine serum albumin (BSA), lysozyme (LYS), and brovin serum fibrinogen (BFG) by 93.4%, 68.3%, 85.6%, respectively, compared to the unmodified PU film. The competitive adsorption of three proteins indicated that LYS preferentially adsorbed on the modified PU film, while BFG had the lowest adsorption selectivity. And the amount of BFG on PU–PVP (6.0 h) film reduced greatly to 0.08 μg/cm{sup 2}, which was almost one-tenth of its adsorption from the single-protein system. Presented results suggested that both hydrophilicity and surface roughness might be the important factors in all cases of protein adsorption, and the competitive or selective adsorption might be related to the size of the proteins, especially on the non-charged films.

Radiochemical separation of actinides for their determination in environmental samples and waste products

Energy Technology Data Exchange (ETDEWEB)

Gleisberg, B [Nuclear Engineering and Analytics Rossendorf, Inc. (VKTA), Dresden (Germany)

1997-03-01

The determination of low level activities of actinides in environmental samples and waste products makes high demands on radiochemical separation methods. Artificial and natural actinides were analyzed in samples form the surrounding areas of NPP and of uranium mines, incorporation samples, solutions containing radioactive fuel, solutions and solids resutling from the process, and in wastes. The activities are measured by {alpha}-spectrometry and {gamma}-spectrometry. (DG)

Physical Stability of Octenyl Succinate-Modified Polysaccharides and Whey Proteins for Potential Use as Bioactive Carriers in Food Systems.

Science.gov (United States)

Puerta-Gomez, Alex F; Castell-Perez, M Elena

2015-06-01

The high cost and potential toxicity of biodegradable polymers like poly(lactic-co-glycolic)acid (PLGA) has increased the interest in natural and modified biopolymers as bioactive carriers. This study characterized the physical stability (water sorption and state transition behavior) of selected starch and proteins: octenyl succinate-modified depolymerized waxy corn starch (DWxCn), waxy rice starch (DWxRc), phytoglycogen, whey protein concentrate (80%, WPC), whey protein isolate (WPI), and α-lactalbumin (α-L) to determine their potential as carriers of bioactive compounds under different environmental conditions. After enzyme modification and particle size characterization, glass transition temperature and moisture isotherms were used to characterize the systems. DWxCn and DWxRc had increased water sorption compared to native starch. The level of octenyl succinate anhydrate (OSA) modification (3% and 7%) did not reduce the water sorption of the DWxCn and phytoglycogen samples. The Guggenheim-Andersen-de Boer model indicated that native waxy corn had significantly (P whey proteins had higher glass transition temperature (Tg) values. On the other hand, depolymerized waxy starches at 7%-OSA modification had a "melted" appearance when exposed to environments with high relative humidity (above 70%) after 10 days at 23 °C. The use of depolymerized and OSA-modified polysaccharides blended with proteins created more stable blends of biopolymers. Hence, this biopolymer would be suitable for materials exposed to high humidity environments in food applications. © 2015 Institute of Food Technologists®

Phenolsulphotransferase in human tissue: radiochemical enzymatic assay and biochemical properties

International Nuclear Information System (INIS)

Anderson, R.J.; Weinshilboum, R.M.

1980-01-01

Phenolsulphotransferase (EC 2.8.2.1) (PST) is an important catecholamine and drug metabolizing enzyme. Optimal conditions have been determined for the accurate measurement of PST activity in the human platelet, human renal cortex, and human jejunum with a radiochemical microassay. 3-Methoxy-4-hydroxyphenylglycol (MHPG) and 35 S-3'-phosphoadenosine-5'-phosphosulfate ( 35 S-PAPS) were the substrates for the reaction. The apparent Michaelis-Menten (Ksub(m)) values for MHPG with platelet, renal cortex, and jejunum were 1.09, 0.46 and 1.16 mmol/l, respectively. Apparent Ksub(m) values for PAPS in the same tissues were 0.14, 0.13 and 0.21 μmol/l. The pH optimum of the reacton in all three tissues was approximately 6.2-6.8 with three different buffer systems. The coefficients of variation for the assay of platelet, renal cortex, and jejunal activities were 6.2%, 3.4% and 4.4%, respectively. Mean platelet PST activity in blood samples from 75 randomly selected adult subjects was 5.0 +- 1.72 mmol of MHPG sulfate formed per hour per mg of platelet protein (8.3 X 10 -5 +- 2.9 X 10 -5 μmol min -1 mg -1 , mean +- S.D.). There was a 5-fold intersubject variation in platelet PST activity within two standard deviations of the mean value. Experiments in which partially purified human erythrocyte PST was added to platelet, kidney and gut homogenates under these assay conditions provided evidence that endogenous PST inhibitors did not affect the observed enzyme activity. (Auth.)

Determination of radiochemical purity of 125I-TOC and 125I-F-PGA

International Nuclear Information System (INIS)

Yang Keya; Fan Wo; Zhang Youjiu; Xu Yujie; Zhu Ran; Hu Mingjiang

2006-01-01

To explore whether there is accordance among three determination methods of the radiochemical purity of [Tyr 3 ] octreotide (TOC) and folate-penicillin G amidase conjugate (F-PGA), which are both labeled with 125 I by Iodogen method, the RCP of the labelings are determined by high performance liquid chromatography (HPLC), paper chromatography and trichloroacetic acid (TCA) precipitation, in which four different concentrations of proteins are used to investigate the effect of them on the determination of RCP. It is shown that both HPLC and paper chromatography can separate the labelings from free iodine efficiently, though HPLC is the most precise and reliable method to determinate RCP of such labelings. In TCA precipitation, the RCP measured with 0.2%BSA is the lowest, but those with three other concentrations of the BSA are similar (P>0.05). When RCP 0.05), whereas higher than that with HPLC (P 10%, the RCP of 125 I-TOC obtained by TCA precipitation is a bit lower than those by two other methods (P 0.05), and there are no significant differences to determinate the RCP of 125 I-F-PGA (P>0.05). The three methods are correlated each other (r=0.0996-0.999, P<0.001). (authors)

TaBoo SeArch Algorithm with a Modified Inverse Histogram for Reproducing Biologically Relevant Rare Events of Proteins.

Science.gov (United States)

Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

2016-05-10

The TaBoo SeArch (TBSA) algorithm [ Harada et al. J. Comput. Chem. 2015 , 36 , 763 - 772 and Harada et al. Chem. Phys. Lett. 2015 , 630 , 68 - 75 ] was recently proposed as an enhanced conformational sampling method for reproducing biologically relevant rare events of a given protein. In TBSA, an inverse histogram of the original distribution, mapped onto a set of reaction coordinates, is constructed from trajectories obtained by multiple short-time molecular dynamics (MD) simulations. Rarely occurring states of a given protein are statistically selected as new initial states based on the inverse histogram, and resampling is performed by restarting the MD simulations from the new initial states to promote the conformational transition. In this process, the definition of the inverse histogram, which characterizes the rarely occurring states, is crucial for the efficiency of TBSA. In this study, we propose a simple modification of the inverse histogram to further accelerate the convergence of TBSA. As demonstrations of the modified TBSA, we applied it to (a) hydrogen bonding rearrangements of Met-enkephalin, (b) large-amplitude domain motions of Glutamine-Binding Protein, and (c) folding processes of the B domain of Staphylococcus aureus Protein A. All demonstrations numerically proved that the modified TBSA reproduced these biologically relevant rare events with nanosecond-order simulation times, although a set of microsecond-order, canonical MD simulations failed to reproduce the rare events, indicating the high efficiency of the modified TBSA.

Radiochemical determination and separation or total radium, 226Ra and 224Ra

International Nuclear Information System (INIS)

Suarez, J. A.; Gonzalez, J. A.; Pablo, M. A. de

1987-01-01

Radiochemical purification and separation of radium has been carried out and the determination of total radium solubilized in aqueous samples has been studied assuming that all the alpha emitters of the sample have their origin in the 226Ra and elements of its desintegration chain. Also, the activities of 22Ra and 226 Ra have been evaluated separately doing a measurement after the chemical separation of the radium and another one 10 days after. (Author) 9 refs

[The effect of hydrophobic surface properties of protein on its resistance to denaturation by organic solvents (using modified alpha-chymotrypsin as an example].

Science.gov (United States)

Kudriashova, E V; Belova, A B; Vinogradov, A A; Mozhaev, V V

1994-03-01

Catalytic activity of covalently modified alpha-chymotrypsin in water/cosolvent solutions was investigated. The stability of chymotrypsin increases upon modification with hydrophilic reagents, such as glyceraldehyde, pyrometallic and succinic anhydrides, and glucosamine. Correlation was observed between the protein's stability in organic solvents and the degree of hydrophilization of the protein's surface. The protein is the more stable, the higher are the modification degree and the hydrophilicity of the modifying residue. At a certain critical hydrophilization degree of chymotrypsin a limit of stability is achieved. The stabilization effect can be accounted for by the fact that the interaction between water molecules on the surface and protein's functional groups become stronger in the hydrophilized protein.

Procedural and developmental aspects of a multielement automatic radiochemical machine, applied to neutron irradiated biomedical samples

International Nuclear Information System (INIS)

Iyengar, G.V.

1976-06-01

This report is intended to serve as a practical guide, elaborately describing the working details and some developmental work connected with an automatic multielement radiochemical machine based on thermal neutron activation analysis using ion exchange and partition chromatography. Some of the practical aspects and personal observations after much experience with this versatile multielement method, applied to investigate the elemental composition of different biomedical matrices, are summarized. Standard reference materials are analyzed, and the data are presented with a set of gamma-spectra obtained before and after chemical separation into convenient groups suitable for gamma spectroscopy. The samples analyzed included various human and animal tissues, body fluids, IAEA biological standard reference materials, and samples from the WHO/IAEA project on 'Trace elements in relation to cardiovascular diseases'. Simplified modifications of the radiochemical processing, suitable for fast and routine analysis of clinical samples have also been discussed. (orig.) [de

Radiochemical procedure for the determination of plutonium isotopes in powdered milk

International Nuclear Information System (INIS)

Taddei, M.H.T.; Silva, N.C.

2006-01-01

A radiochemical procedure for the determination of alpha-emitting isotopes of plutonium in powdered milk is proposed. The procedure involves sample dissolution (by HNO 3 and HClO 4 ), separation by ionic-exchange resin, electrodeposition and alpha-spectroscopy. In order to determine the chemical recovery, 242 Pu was employed as a tracer. A reference material (Marine Sediment IAEA 135) was analyzed to validate such procedure, and to show its reliability. Afterwards, some powdered milk, produced for international trade, was analyzed and chemical recovery was found to be around 95%. (author)

Radiolabeling of anti-CD20 with Re-188 for treatment of non-Hodgkin's lymphoma: radiochemical control

International Nuclear Information System (INIS)

Dias, Carla R.; Osso Junior, Joao A.

2009-01-01

The development of tumor-selective radiopharmaceuticals is clinically desirable as a means of detecting or confirming the presence and location of primary and metastatic lesions and monitoring tumor response to (chemo)therapy. In addition, the application of targeted radiotherapeutics provides a unique and effective modality for direct tumor treatment. In this manner the radioimmunotherapy (RIT) uses the targeting features of monoclonal antibody to deliver radiation from an attached radionuclide. Antibody therapy directed against the CD20 antigen on the surface of B-cells is considered one of the first successful target-specific therapies in oncology. The radionuclide rhenium-188 ( 188 Re) is currently produced from the father nuclide tungsten-188 ( 188 W) through a transportable generator system. Because of its easy availability and suitable nuclear properties (EβMAX = 2.1 MeV, t 1/2 = 16.9 h, Eγ = 155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agent and could be conveniently utilized for imaging and dosimetric purposes. The purpose of this work is to show the radiochemical control of the optimized formulation (solution) and lyophilized formulation (kit) of labeled rituximab (anti-CD20) with 188 Re. Rituximab was reduced by incubation with 2-mercaptoethanol at room temperature. The number of resulting free sulfhydryl groups was assayed with Ellman's reagent. Radiochemical purity of 188 Re-rituximab was evaluated using instant thin layer chromatography-silica gel (ITLC-SG). Quality control methods for evaluation of radiochemical purity showed good labeling yield of the antibody. (author)

Evaluation of a modified IRMA for anti-D quantitation, using 3H protein A

International Nuclear Information System (INIS)

Dumasia, A.; Gupte, S.

1993-01-01

A modified immunoradiometric assay (IRMA) using tritiated ( 3 H) protein A was developed to estimate anti-D concentration. The main advantages of the assay were longer shelf life of the labelled reagent (more than two years); minimum radiation hazard and; low non specific binding. Levels of anti-D were estimated in 23 Rh (D) immunized women. A good correlation of anti-D concentration (μg/ml) with Rh antibody titre was observed (r=+ 0.89, P 3 H protein A IRMA correlated well with the severity of Rh-HDN. This assay could quantitate anti-D in sera having exclusively IgG 3 subtype. (author). 20 refs., 2 figs., 2 tabs

Analysis of potential protein-modifying variants in 9000 endometriosis patients and 150000 controls of European ancestry

DEFF Research Database (Denmark)

Sapkota, Yadav; Vivo, Immaculata De; Steinthorsdottir, Valgerdur

2017-01-01

-modifying variants in endometriosis using exome-array genotyping in 7164 cases and 21005 controls, and a replication set of 1840 cases and 129016 controls of European ancestry. Results in the discovery sample identified significant evidence for association with coding variants in single-variant (rs1801232-CUBN...... sufficient power, our results did not identify any protein-modifying variants (MAF > 0.01) with moderate or large effect sizes in endometriosis, although these variants may exist in non-European populations or in high-risk families. The results suggest continued discovery efforts should focus on genotyping...

Labeling of thymidine analog with an organometallic complex of technetium-99m for diagnostic of cancer: radiochemical and biological evaluation

International Nuclear Information System (INIS)

Santos, Rodrigo Luis Silva Ribeiro

2007-01-01

Thymidine analogs have been labeled with different radioisotopes due to their potential in monitoring the uncontrollable cell proliferation. Considering that the radioisotopes technetium-99m still keep a privileged position as a marker due to its chemical and nuclear properties, this dissertation was constituted by the developed of a new technique of labeling of thymidine analog with 99m Tc, by means of the organometallic complex. The aims of this research were: synthesis of the organometallic complex technetium-99m-carbonyl, thymidine labeling with this precursor, evaluation of stability, and radiochemical e biological evaluation with healthy and tumor-bearing animals. The preparation of the organometallic precursor, using the CO gas, was easily achieved, as well as the labeling of thymidine with this precursor, resulting itself a radiochemical pureness of ≥ 97% and ≥ 94%, respectively. Chromatography systems with good levels of trustworthiness were used, ensuring the qualification and quantification of the radiochemical samples. The result of in vitro testing of lipophilicity disclosed that the radiolabeled complex is hydrophilic, with a partition coefficient (log P) of -1.48. The precursor complex and the radiolabeled have good radiochemical stability up to 6 h in room temperature. The cysteine and histidine challenge indicated losses between 8 and 1 1 % for concentrations until 300 mM. The biodistribution assay in healthy mice revealed rapid blood clearance and low uptake by general organs with renal and hepatobiliary excretion. The tumor concentration was low with values of 0.28 and 0.18 %ID/g for lung and breast cancer, respectively. The results imply more studies in other tumor models or the modification of the structure of the organic molecule that act like ligand. (author)

Crystallization and molecular-replacement studies of the monoclonal antibody mAbR310 specific for the (R)-HNE-modified protein

International Nuclear Information System (INIS)

Ito, Sohei; Tatsuda, Emi; Ishino, Kousuke; Suzuki, Kenichiro; Sakai, Hiroshi; Uchida, Koji

2006-01-01

Antigen-free Fab fragment of mAbR310, which recognizes (R)-HNE modified protein, has been crystallized. Initial phases have been obtained by molecular replacement. 4-Hydroxy-2-nonenal (HNE), a major racemic product of lipid peroxidation, reacts with histidine to form a stable HNE–histidine Michael addition-type adduct possessing three chiral centres in the cyclic hemiacetal structure. Monoclonal antibodies against HNE-modified protein have been widely used for assessing oxidative stress in vitro and in vivo. Here, the purification, crystallization and preliminary crystallographic analysis of a Fab fragment of novel monoclonal antibody R310 (mAbR310), which recognizes (R)-HNE-modified protein, are reported. The Fab fragment of mAbR310 was obtained by digestion with papain, purified and crystallized. Using hanging-drop vapour-diffusion crystallization techniques, crystals of mAbR310 Fab were obtained. The crystal belongs to the monoclinic space group C2 (unit-cell parameters a = 127.04, b = 65.31, c = 64.29 Å, β = 118.88°) and diffracted X-rays to a resolution of 1.84 Å. The asymmetric unit contains one molecule of mAbR310, with a corresponding crystal volume per protein weight of 2.51 Å 3 Da −1 and a solvent content of 51.0%

Cyclotron production, radiochemical separation and quality control of platinum radiotracers for toxicological studies

International Nuclear Information System (INIS)

Bonardi, M.; Birattari, C.; Groppi, F.; Arginelli, D.; Gini, L.; Gallorini, M.

1998-01-01

The increasing concentration of Pt, Pd and Rh in the environment is mainly due to the release of these elements from the catalytic converters of the motorvehicles. This situation makes it necessary to carry out metallotoxicological experiments on both cell cultures and laboratory animals, in order to assess their impact on living organisms after a Long Term and Low Level Exposure (LLE). Both nuclear reactions nat Ir(p,xn) and nat Os(α,xn) were investigated in the energy range up to 45 MeV for protons and 38 MeV for alpha-particles, in order to optimize the irradiation parameters for the production of 188,189,191 Pt. Several sets of thin- and thick-target excitation functions were determined experimentally by cyclotron irradiation at both Milano and Ispra cyclotrons. This paper reports the irradiation parameters studied and adopted and two radiochemical procedures for the separation of radio-Pt from an Os target, as well as from ruthenium, iridium and gold impurities. These procedures were used to obtain very high specific activity Pt radionuclides in No Carrier Added (NCA) form. Radionuclidic, radiochemical and chemical purity measurements were carried out by the use of several techniques like γ-spectrometry, ion-exchange radio-chromatography, atomic absorption spectrometry and neutron activation analysis. (author)

RAPID AUTOMATED RADIOCHEMICAL ANALYZER FOR DETERMINATION OF TARGETED RADIONUCLIDES IN NUCLEAR PROCESS STREAMS

International Nuclear Information System (INIS)

O'Hara, Matthew J.; Durst, Philip C.; Grate, Jay W.; Egorov, Oleg; Devol, Timothy A.

2008-01-01

Some industrial process-scale plants require the monitoring of specific radionuclides as an indication of the composition of their feed streams or as indicators of plant performance. In this process environment, radiochemical measurements must be fast, accurate, and reliable. Manual sampling, sample preparation, and analysis of process fluids are highly precise and accurate, but tend to be expensive and slow. Scientists at Pacific Northwest National Laboratory (PNNL) have assembled and characterized a fully automated prototype Process Monitor instrument which was originally designed to rapidly measure Tc-99 in the effluent streams of the Waste Treatment Plant at Hanford, WA. The system is capable of a variety of tasks: extraction of a precise volume of sample, sample digestion/analyte redox adjustment, column-based chemical separations, flow-through radiochemical detection and data analysis/reporting. The system is compact, its components are fluidically inter-linked, and analytical results can be immediately calculated and electronically reported. It is capable of performing a complete analytical cycle in less than 15 minutes. The system is highly modular and can be adapted to a variety of sample types and analytical requirements. It exemplifies how automation could be integrated into reprocessing facilities to support international nuclear safeguards needs

Hot-spot analysis to dissect the functional protein-protein interface of a tRNA-modifying enzyme.

Science.gov (United States)

Jakobi, Stephan; Nguyen, Tran Xuan Phong; Debaene, François; Metz, Alexander; Sanglier-Cianférani, Sarah; Reuter, Klaus; Klebe, Gerhard

2014-10-01

Interference with protein-protein interactions of interfaces larger than 1500 Ų by small drug-like molecules is notoriously difficult, particularly if targeting homodimers. The tRNA modifying enzyme Tgt is only functionally active as a homodimer. Thus, blocking Tgt dimerization is a promising strategy for drug therapy as this protein is key to the development of Shigellosis. Our goal was to identify hot-spot residues which, upon mutation, result in a predominantly monomeric state of Tgt. The detailed understanding of the spatial location and stability contribution of the individual interaction hot-spot residues and the plasticity of motifs involved in the interface formation is a crucial prerequisite for the rational identification of drug-like inhibitors addressing the respective dimerization interface. Using computational analyses, we identified hot-spot residues that contribute particularly to dimer stability: a cluster of hydrophobic and aromatic residues as well as several salt bridges. This in silico prediction led to the identification of a promising double mutant, which was validated experimentally. Native nano-ESI mass spectrometry showed that the dimerization of the suggested mutant is largely prevented resulting in a predominantly monomeric state. Crystal structure analysis and enzyme kinetics of the mutant variant further support the evidence for enhanced monomerization and provide first insights into the structural consequences of the dimer destabilization. © 2014 Wiley Periodicals, Inc.

Radiochemical and thermal studies of the copper(II)-exchanged form of synthetic zeolite linde sieve A

International Nuclear Information System (INIS)

Banerjee, S.P.

1978-01-01

Synthetic zeolite Linde Sieve A displays a double ion-sieve action. Only small cations can penetrate the single 6-rings into the beta cages. The radiochemical and thermal studies of copper(II)-exchanges form of 4A shows evidence of hydrated copper(II) ions in the zeolite structure. (author)

Integral method of treatment of experimental data from radiochemical solar neutrino detectors

International Nuclear Information System (INIS)

Gavrin, V.N.; Kopylov, A.V.; Streltsov, A.V.

1985-01-01

An analysis is made of the statistical errors in solar neutrino detection by radiochemical detectors at different times of exposure. It is shown that short exposures (tau/sub e/ = one-half to one half-life) give minimal one-year error. The possibility is considered of the detection of the solar neutrino flux variation due to annual changes of the Earth-Sun distance. The integral method of treatment of the experimental data is described. Results are given of the statistical treatment of computer simulated data

Radiochemical analysis of a wide range of 131I activities in water and milk using well-type germanium detector

International Nuclear Information System (INIS)

Xin Li; Bradt, C.J.; Umme-Farzana Syed; Abdul Bari; Torres, M.A.; Kimi Nishikawa; Khan, A.J.; Menia, T.A.; Semkow, T.M.; University at Albany, State University of New York, Rensselaer, NY

2017-01-01

We report a study of a fast radiochemical method to determine the activity of 131 I via the radiochemical recovery obtained with a 129 I tracer. Previous methods were valid for low levels of 131 I activities. In the new method, we developed a correction using the 29.7-keV X-ray peak from Xe, taking into consideration that this peak originates from both and 131 I decay. This enables quantitation of high levels of 131 I activity. Furthermore, for a very high 131 I activity, one can use the 39.6-keV gamma peak which is unique to 129 I. Combining both approaches enables quantitation of 131 I activities up to 200 times that of the 129 I recovery tracer. (author)

Spectroscopic detection of fluorescent protein marker gene activity in genetically modified plants

Science.gov (United States)

Liew, O. W.; Chong, Jenny P. C.; Asundi, Anand K.

2005-04-01

This work focuses on developing a portable fibre optic fluorescence analyser for rapid identification of genetically modified plants tagged with a fluorescent marker gene. Independent transgenic tobacco plant lines expressing the enhanced green fluorescence protein (EGFP) gene were regenerated following Agrobacterium-mediated gene transfer. Molecular characterisation of these plant lines was carried out at the DNA level by PCR screening to confirm their transgenic status. Conventional transgene expression analysis was then carried out at the RNA level by RT-PCR and at the protein level by Western blotting using anti-GFP rabbit antiserum. The amount of plant-expressed EGFP on a Western blot was quantified against known amounts of purified EGFP by scanning densitometry. The expression level of EGFP in transformed plants was found to range from 0.1 - 0.6% of total extractable protein. A comparison between conventional western analysis of transformants and direct spectroscopic quantification using the fibre optic fluorescence analyser was made. The results showed that spectroscopic measurements of fluorescence emission from strong EGFP expressors correlated positively with Western blot data. However, the fluorescence analyser was also able to identify weakly expressing plant transformants below the detection limit of colorimetric Western blotting.

High radiochemical yield synthesis of [18F]FLT from 3'-O-nosylated thymidine and its 3-N-BOC-protected analogue

International Nuclear Information System (INIS)

Yoon, M. K.; Oh, S. J.; Ryu, J. S.; Moon, D. H.

2002-01-01

We synthesized 3'-O-nosylate and its 3-N-BOC-protected thymidine derivatives as two precursors for high radiochemical yield synthesis of [ 18 F]FLT and optimized [ 18 F]fluorination conditions. (5'-O-DMTr-2'-deoxy-3'-O-nosyl-β-D-threo-pentofuranosyl)thymidine and its s 3-N-BOD-protected analogue were prepared with 54% and 28% yield, respectively. After drying of [ 18 F]F-, 3'-O-nosylate(10-30 mg) or its 3-N-BOC-protected(11-34 mg) precursor was added to 500 μl of CH3CN, respectively. The mixtures were heated at 100-130 .deg. C for 5-30 min. For hydrolysis, 250-500 μl 1N HCl at 50 .deg. C for 5 min condition was used and 1.5ml of 2M sodium acetate was used for neutralization. Reaction mixture was purified by HPLC. The optimal [ 18 F]fluorination yield of 3'-O-nosylate precursor was 85±5.4% with 34 mg of precursor and a reaction time of 5 min at 130 .deg. C. For 3-N-BOC-protected analogue, [ 18 F]fluorination yield was 82±5.4% with 34 mg of precursor and a reaction time of 5 min at 110. deg. C. After HPLC purification, overall radiochemical yield using each precursors were 40±5.2% and 42±5.4% and radiochemical purity were 98±0.5% and 97±2.1% for two precursors, respectively. Preparation time was 60±10.5 min including HPLC purification for two precursors. From these two precursors, [ 18 F]FLT can be easily prepared with high radiochemical yield. 3-N-BOC-protected precursor required milder [ 18 F]fluorination conditions than 3'-O-nosylate precursor

The platinum group elements and gold: analysis by radiochemical and instrumental neutron activation analysis and relevance to geological exploration and related problems

Energy Technology Data Exchange (ETDEWEB)

Reeves, S; Plimer, I R [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1997-12-31

This paper presents an overview of research conducted with the support of the Australian Institute of Nuclear Science and Engineering, at the University of Melbourne, School of Earth Sciences, Radiochemical Neutron Activation Laboratory. The primary objective of this research is to realize the high potential of the platinum group elements (PGE) and gold to the solution of petrogenetic problems, the study of magma generation and magmatic processes in mafic/ultramafic rock suites, as tracers in hydrothermal ore formation. The PGEs (Os, Ru, Ir, Pt, Pd and Rh) are among the least abundant of all elements on earth with unique properties such as high melting points, high electrical and thermal conductivity, high density, strength and toughness as alloys. They exhibit both siderophile and chalcophile characteristics and are valuable tools in providing information about magmatic processes, in particular S-saturation, as well as crystal fractionation trends. Two distinct groups of PGEs are discerned; the IPGEs (Ru, Os, Ir) and the PPGEs (Pt, Pd, Rh, Au) on the basis of their behaviour during fractionation processes. Using chondrite normalized PGE patterns it is possible to distinguish between sulphides that segregated from primitive magmas, such as komatiites, and sulphides which segregated from more fractionated magmas, such as tholeiites. It is critical to the understanding of these processes to be able to analyse key elements, such as the PGE and gold, in the parts per billion to parts per trillion range. Platinum group elements and Au were determined by radiochemical neutron activation analysis using a modified NiS fire-assay preconcentration technique, adapted from procedures first used by Robert, R.V. D. and van Wyk, E. (1975) . Detection limits are generally 0.005-0.01 ppb (Au and Ir), 0.1-0.2 ppb (Pd and Pt), and 0.1-0.5 ppb for Ru. 9 refs.

The platinum group elements and gold: analysis by radiochemical and instrumental neutron activation analysis and relevance to geological exploration and related problems

Energy Technology Data Exchange (ETDEWEB)

Reeves, S.; Plimer, I. R. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1996-12-31

This paper presents an overview of research conducted with the support of the Australian Institute of Nuclear Science and Engineering, at the University of Melbourne, School of Earth Sciences, Radiochemical Neutron Activation Laboratory. The primary objective of this research is to realize the high potential of the platinum group elements (PGE) and gold to the solution of petrogenetic problems, the study of magma generation and magmatic processes in mafic/ultramafic rock suites, as tracers in hydrothermal ore formation. The PGEs (Os, Ru, Ir, Pt, Pd and Rh) are among the least abundant of all elements on earth with unique properties such as high melting points, high electrical and thermal conductivity, high density, strength and toughness as alloys. They exhibit both siderophile and chalcophile characteristics and are valuable tools in providing information about magmatic processes, in particular S-saturation, as well as crystal fractionation trends. Two distinct groups of PGEs are discerned; the IPGEs (Ru, Os, Ir) and the PPGEs (Pt, Pd, Rh, Au) on the basis of their behaviour during fractionation processes. Using chondrite normalized PGE patterns it is possible to distinguish between sulphides that segregated from primitive magmas, such as komatiites, and sulphides which segregated from more fractionated magmas, such as tholeiites. It is critical to the understanding of these processes to be able to analyse key elements, such as the PGE and gold, in the parts per billion to parts per trillion range. Platinum group elements and Au were determined by radiochemical neutron activation analysis using a modified NiS fire-assay preconcentration technique, adapted from procedures first used by Robert, R.V. D. and van Wyk, E. (1975) . Detection limits are generally 0.005-0.01 ppb (Au and Ir), 0.1-0.2 ppb (Pd and Pt), and 0.1-0.5 ppb for Ru. 9 refs.

The platinum group elements and gold: analysis by radiochemical and instrumental neutron activation analysis and relevance to geological exploration and related problems

International Nuclear Information System (INIS)

Reeves, S.; Plimer, I. R.

1996-01-01

This paper presents an overview of research conducted with the support of the Australian Institute of Nuclear Science and Engineering, at the University of Melbourne, School of Earth Sciences, Radiochemical Neutron Activation Laboratory. The primary objective of this research is to realize the high potential of the platinum group elements (PGE) and gold to the solution of petrogenetic problems, the study of magma generation and magmatic processes in mafic/ultramafic rock suites, as tracers in hydrothermal ore formation. The PGEs (Os, Ru, Ir, Pt, Pd and Rh) are among the least abundant of all elements on earth with unique properties such as high melting points, high electrical and thermal conductivity, high density, strength and toughness as alloys. They exhibit both siderophile and chalcophile characteristics and are valuable tools in providing information about magmatic processes, in particular S-saturation, as well as crystal fractionation trends. Two distinct groups of PGEs are discerned; the IPGEs (Ru, Os, Ir) and the PPGEs (Pt, Pd, Rh, Au) on the basis of their behaviour during fractionation processes. Using chondrite normalized PGE patterns it is possible to distinguish between sulphides that segregated from primitive magmas, such as komatiites, and sulphides which segregated from more fractionated magmas, such as tholeiites. It is critical to the understanding of these processes to be able to analyse key elements, such as the PGE and gold, in the parts per billion to parts per trillion range. Platinum group elements and Au were determined by radiochemical neutron activation analysis using a modified NiS fire-assay preconcentration technique, adapted from procedures first used by Robert, R.V. D. and van Wyk, E. (1975) . Detection limits are generally 0.005-0.01 ppb (Au and Ir), 0.1-0.2 ppb (Pd and Pt), and 0.1-0.5 ppb for Ru. 9 refs

Comparison study among methodologies of planar chromatography for radiochemical control of technetium-99m

International Nuclear Information System (INIS)

Monteiro, Elisiane de Godoy

2012-01-01

Radiopharmaceuticals are substances that have radioisotopes in their composition. About 95% of the procedures performed in nuclear medicine use radiopharmaceuticals with diagnostic purposes, and the Lyophilized Reagents (LR) labeled with Technetium-99m ( 99 mTc), obtained from 99 Mo/ 99 mTc generator, are the most one used. Quality Control represents the set of assays to be performed to assure that the product is adequate to its purpose. An important feature to be evaluated in 99m Tc radiopharmaceuticals is the radiochemical purity (% RqP) to quantify free pertechnetate ( 99 mTcO 4 - ) and technetium colloidal (99mTcO 2 ) mainly by paper chromatography (PC), thin layer (TLC) and High Performance Liquid Chromatography (HPLC). The objective of this work was to perform the comparison among the radiochemical control methodologies of LR labeled with 99m Tc, described in the United States Pharmacopoeia (USP) and European Pharmacopoeia (EP) and those used by IPEN. 99m TcO 4 - eluate and DISIDA, DMSA, DTPA, EC, ECD, GHA, MIBI, MDP, PIRO, SAH and Sn Coloidal LR were provided by IPEN-CNEN/SP. TLC-cellulose, TLC-SG.TLC-SG reverse phase, HPTLC-cellulose, HPTLC-SG (Merck) and ITLC-SG (Pall Corporation), W1MM, W3MM, W17M e W31ET (Whatman) chromatographic plates were used. The measurement of the radioactivity was done in a Perkin Elmer Cobra D-5002 gamma counter. LR were labeled to obtain 55,0 MBq mL 1 (1,5 mCi mL 1 ) of final radioactive concentration. The % 99m TcO 4 - , % 99m TcO 2 and % RqP were determined up to 4 hour labeling. From 11 LR, only EC and GHA have no radiochemical control methods in USP and EP. In USP and/or EP, DTPA, MDP, PIRO, SAH and Sn Coloidal methods use ITLC-SG; IPEN uses this chromatography plate in DISIDA, EC, ECD, GHA, PIRO, MIBI and SAH. As ITLC-SG had been out of production (recommended in 40, 70 and 41% of the USP, EP and IPEN methodologies, respectively), it was necessary to search alternatives to replace ITLC-SG plate in the radiochemical control

Radiochemical analysis in the nuclear research establishment (KFA) Juelich, FRG

International Nuclear Information System (INIS)

Anon.

1975-01-01

KFA Juelich is one of the two great nuclear research centres of the Federal Republic of Germany. About 3700 employees including about 700 scientists are engaged in a great number of programs and projects belonging to six main fields of research and development: high temperature reactor and energy techniques; nuclear fusion; properties of materials; materials research; life and environment; methods. In the article the radiochemical analysis work of the former Central Institute of Analytical Chemistry and its two successors is described: activation analysis, application of tracer techniques, fission product analysis. Further on the irradiation facilities are described, a short survey is given on the instrumentation, and the future work is outlined. (T.G.)

15th radiochemical conference: Booklet of abstracts and conference programme

International Nuclear Information System (INIS)

John, J.; Benes, P.; Kucera, J.; Havela, L.; Bartonicek, B.; Vobecky, M.; Krizova, V.; Kopicka, K.; Prasil, Z.

2006-04-01

The conference was structured as follows: Opening plenary lectures (6 lectures); Topic 1 - radionuclides in the environment, radioecology (22 verbal presentations (VPs), 23 poster presentations (PPs)); Topic 2 - nuclear analytical methods (22 VPs, 32 PPs); Topic 3 - chemistry of actinide and transactinide elements (8 VPs, 10 PPs); Topic 4 - radiation chemistry (9 VPs, 5 PPs); Topic 5 - production and application of radionuclides (17 VPs, 6 PPs); Topic 6 - separation methods, speciation (21 VPs, 23 PPs); Topic 7 - chemistry of nuclear fuel cycle, radiochemical problems in nuclear waste management (20 VPs, 16 PPs); Topic 8 - nuclear methods in medicine, radiopharmaceuticals, and radiodiagnostics, labelled compounds (8 VPs, 7 PPs); and Panels (2 introductions). (P.A.)

Radiochemical methods for studying lipase-catalyzed interesterification of lipids

International Nuclear Information System (INIS)

Schuch, R.; Mukherjee, K.D.

1987-01-01

Reactions involving lipase-catalyzed interesterification of lipids, which are of commendable interest in biotechnology, have been monitored and assayed by radiochemical methods using 14 C-labeled substrates. Medium chain (C 12 plus C 14 ) triacylglycerols were reacted in the presence of an immobilized lipase from Mucor miehei and hexane at 45 0 C with methyl [1- 14 C]oleate, [1- 14 C]oleic acid, [carboxyl- 14 C]trioleoylglycerol, [1- 14 C]octadecenyl alcohol, and [U- 14 C]glycerol, each of known specific activity. The reactions were monitored and the rate of interesterification determined by radio thin layer chromatography from the incorporation of radioactivity into acyl moieties of triacylglycerols (from methyl oleate, oleic acid, and trioleoylglycerol), alkyl moieties of wax esters (from octadecenyl alcohol), and into glycerol backbone of monoacylglycerols and diacylglycerols (from glycerol). (orig.)

Radiochemical neutron activation analysis of gold in geochemical samples

International Nuclear Information System (INIS)

Zilliacus, R.

1983-01-01

A fast method for the radiochemical neutron activation analysis of gold in geochemical samples is described. The method is intended for samples having background concentrations of gold. The method is based on the dissolution of samples with hydrofluoric acid and aqua regia followed by the dissolution of the fluorides with boric acid and hydrochloric acid. Gold is then adsorbed on activated carbon by filtrating the solution through a thin carbon layer. The activity measurements are carried out using a Ge(Li)-detector and a multichannel analyzer. The chemical yields of the separation determined by reirradiation vary between 60 and 90%. The detection limit of the method is 0.2 ng/g gold in rock samples. USGS standard rocks and exploration reference materials are analyzed and the results are presented and compared with literature data. (author)

Radiochemical plasma salicylamide assay using ring-labeled tritiated salicylamide

Energy Technology Data Exchange (ETDEWEB)

Stella, V J; Varia, S A; Riedy, M

1979-05-01

A rat plasma salicylamide assay was developed using ring-labeled tritiated salicylamide, synthesized by reacting salicylamide with tritium oxide in the presence of heptafluorobutyric acid. The reaction yielded /sup 3/H-salicylamide of specific activity up to 8.41 mCi/mmole, 60% yield. Plasma containing /sup 3/H-salicylamide and its metabolites was extracted with a toluene-based scintillation fluid, which was subsequently counted. Specificity for free salicylamide was demonstrated by radiochemical and standard fluorescence plasma salicylamide level-time curves. Specificity resulted from nonextraction of the salicylamide sulfate and glucuronide metabolites. Sulfatase and beta-glucuronidase treatment allowed the analysis of plasma sulfate and glucuronide conjugates as free salicylamide. This procedure should be effective for the analysis of salicylamide and its metabolites in the presence of similar phenolic compounds.

Radiochemical separations of hafnium, tantalum, and germanium from tungsten and selenium irradiated by 14 MeV neutrons

International Nuclear Information System (INIS)

Blachot, J.; Benabed, A.; Herment, J.; Monnand, E.

1968-01-01

Radiochemical separations of Hf, Ta and Ge from W and Se respectively, after 14 MeV-neutron irradiation. A new isotope: 79 Ge with a half-live of 50 ± 5 s and emitter of a 230 keV γ transition is observed. (authors) [fr

Radiochemical determination of strontium-90 and cesium-137 in waters of the Pacific Ocean and its neighboring seas

International Nuclear Information System (INIS)

Borisenko, G.S.; Kandinskii, P.A.; Gedeonov, L.I.; Ivanova, L.M.; Petrov, A.A.

1987-01-01

Depending on the salinity of the water, two versions of strontium-90 and cesium-137 concentration from water samples are presented. Cesium-137 was concentrated by precipitating sparingly soluble mixed hexacyanoferrates (II), and strontium-90 by precipitating carbonates together with calcium. A scheme has been given for radiochemical analysis of the concentrates. Strontium-90 and cesium-137 contents in the waters of the Pacific Ocean and its neighboring seas have been determined by the radiochemical method described. The levels of radionuclide content in the water and atmospheric precipitations have been shown to be inter-related. Strontium-90 and cesium-137 contents in the surface water of the northwestern Pacific were found to be much lower in 1980 than in the early seventies. The area of technogenic radioactive pollution was found to persist in the region of the Columbia mouth into the Pacific Ocean

The material control and accounting system model development in the Radiochemical plant of Siberian Chemical Combine (SChC)

International Nuclear Information System (INIS)

Kozyrev, A.S.; Purygin, V.Ya.; Skuratov, V.A.; Lapotkov, A.A.

1999-01-01

The nuclear material (NM) control and accounting computerized system is designed to automatically account NM reception, movement and storage at the Radiochemical Plant. The objective of this system development is to provide a constant surveillance over the process material movement, to improve their accountability and administrative work, to upgrade the plant protection against possible NM thefts, stealing and diversion, to rule out any casual errors of operators, to improve the timeliness and significance (reliability) of information about nuclear materials. The NM control and accounting system at the Radiochemical Plant should be based on the computerized network. It must keep track of all the material movements in each Material Balance Areas: material receipt from other plant; material local movement within the plant; material shipment to other plants; generation of required documents about NM movements and its accounting [ru

Pharmacological characterization of receptor-activity-modifying proteins (RAMPs) and the human calcitonin receptor.

Science.gov (United States)

Armour, S L; Foord, S; Kenakin, T; Chen, W J

1999-12-01

Receptor-activity-modifying proteins (RAMPs) are a family of single transmembrane domain proteins shown to be important for the transport and ligand specificity of the calcitonin gene-related peptide (CGRP) receptor. In this report, we describe the analysis of pharmacological properties of the human calcitonin receptor (hCTR) coexpressed with different RAMPs with the use of the Xenopus laevis melanophore expression system. We show that coexpression of RAMP3 with human calcitonin receptor changed the relative potency of hCTR to human calcitonin (hCAL) and rat amylin. RAMP1 and RAMP2, in contrast, had little effect on the change of hCTR potency to hCAL or rat amylin. When coexpressed with RAMP3, hCTR reversed the relative potency by a 3.5-fold loss in sensitivity to hCAL and a 19-fold increase in sensitivity to rat amylin. AC66, an inverse agonist, produced apparent simple competitive antagonism of hCAL and rat amylin, as indicated by linear Schild regressions. The potency of AC66 was changed in the blockade of rat amylin but not hCAL responses with RAMP3 coexpression. The mean pK(B) for AC66 to hCAL was 9.4 +/- 0.3 without RAMP3 and 9.45 +/- 0.07 with RAMP3. For the antagonism of AC66 to rat amylin, the pK(B) was 9.25 +/- 0.15 without RAMP3 and 8.2 +/- 0.35 with RAMP3. The finding suggests that RAMP3 might modify the active states of calcitonin receptor in such a way as to create a new receptor phenotype that is "amylin-like." Irrespective of the physiological association of the new receptor species, the finding that a coexpressed membrane protein can completely change agonist and antagonist affinities for a receptor raises implications for screening in recombinant receptor systems.

Radiochemical analysis of radio-nuclides in sea water collected near Bikini Atoll

Energy Technology Data Exchange (ETDEWEB)

Miyake, Y; Sugiura, Y

1955-01-01

A radiochemical analysis of sea water containing fission materials collected near Bikini Atoll in June, 1954, was performed. The sea water was boiled with hydrochloric acid, iron and lanthanum salts each 5 mg as Fe and La were added to it. They were precipitated as hydroxide, which was dissolved in hydrochloric acid and ferric chloride was extracted with ethyl ether. The remaining solution was evaporated to dryness and the residue was dissolved in hydrochloric acid. Using the latter solution the group separation was done with cation exchanger resins.

Lactose repressor protein modified with dansyl chloride: activity effects and fluorescence properties

International Nuclear Information System (INIS)

Hsieh, W.T.; Matthews, K.S.

1985-01-01

Chemical modification using 5-(dimethylamino)naphthalene-1-sulfonyl chloride (dansyl chloride) has been used to explore the importance of lysine residues involved in the binding activities of the lactose repressor and to introduce a fluorescent probe into the protein. Dansyl chloride modification of lac repressor resulted in loss of operator DNA binding at low molar ratios of reagent/monomer. Loss of nonspecific DNA binding was observed only at higher molar ratios, while isopropyl beta-D-thiogalactoside binding was not affected at any of the reagent levels studied. Lysine residues were the only modified amino acids detected. Protection of lysines-33 and -37 from modification by the presence of nonspecific DNA correlated with maintenance of operator DNA binding activity, and reaction of lysine-37 paralleled operator binding activity loss. Energy transfer between dansyl incorporated in the core region of the repressor protein and tryptophan-201 was observed, with an approximate distance of 23 A calculated between these two moieties

Radiochemical surveillance of KNK primary sodium

International Nuclear Information System (INIS)

Stamm, H.-H.; Stade, K.Ch.

1987-05-01

Radiochemical surveillance of the KNK primary sodium has been performed now for 15 years with 953 effective full-power days. The overflow method used for sodium sampling proved to be reliable. Different crucible materials have been used for different analytical tasks. The amount of radionuclides in the primary system has not given restrictions to plant operation at any time. On-line gamma spectroscopy on pipings and components of the primary circuits was accomplished in reactor downtimes. Activity depositions on the walls were dominated by Ta-182 after KNK I operation. Main deposited activities at KNK II were Mn-54 (fresh core) and after operation with failed fuel Cs-137, in cover gas areas together with Zn-65. Efficient experimental radionuclide traps for the removal of Mn-54, Zn-65 and Cs-137 from the primary coolant were tested successfully. The dose rates on primary pipes and components of KNK I and KNK II were lower by an order of magnitude compared to water-cooled reactors. This is in good agreement with experiences from LMFBR's in other countries. The resulting average yearly accumulated personal dose rate was 0.21 man-Sv at KNK, compared to 3.9 man-Sv at German light-water-cooled power reactors

Radiochemical studies on amorphous zirconium phosphate

Energy Technology Data Exchange (ETDEWEB)

Dyer, A; Moores, G E [Salford Univ. (UK). Dept. of Chemistry and Applied Chemistry

1981-01-01

Amorphous zirconium phosphate (ZrP) is used in some hemodialysis machines for the regeneration of dialysate. Its function is to adsorb ammonium ions formed by the pretreatment of urea by urease. It also adsorbs Ca, Mg and K ions but leaches phosphate ions which are then removed (along with F/sup -/ ions) by a bed of hydrous zirconium oxide. The sodium form of ZrP is used although other forms have been suggested for use. The work reported here describes some preliminary radiochemical studies on the mechanism of release of phosphate ions and its possible relationship to sodium ion-exchange. /sup 32/P labelled material (HHZrP) was used for elution experiments with deionized water and buffer solutions having the pH's 4.2, 7.0 and 9.2. Buffer solutions used were as supplied by BDH. Elution was at four different temperatures in the range 293 to 363/sup 0/C. In the second series of experiments HHZrP was suspended in a NaCl solution labelled with /sup 22/Na. From this, /sup 22/Na labelled ZrP (NaHZrP) was prepared and eluted in the same way as the HHZrP. Results are given and discussed.

Mucosal Immunogenicity of Genetically Modified Lactobacillus acidophilus Expressing an HIV-1 Epitope within the Surface Layer Protein.

Directory of Open Access Journals (Sweden)

Akinobu Kajikawa

Full Text Available Surface layer proteins of probiotic lactobacilli are theoretically efficient epitope-displaying scaffolds for oral vaccine delivery due to their high expression levels and surface localization. In this study, we constructed genetically modified Lactobacillus acidophilus strains expressing the membrane proximal external region (MPER from human immunodeficiency virus type 1 (HIV-1 within the context of the major S-layer protein, SlpA. Intragastric immunization of mice with the recombinants induced MPER-specific and S-layer protein-specific antibodies in serum and mucosal secretions. Moreover, analysis of systemic SlpA-specific cytokines revealed that the responses appeared to be Th1 and Th17 dominant. These findings demonstrated the potential use of the Lactobacillus S-layer protein for development of oral vaccines targeting specific peptides.

Determination of chromium, cobalt and nickel in tissue samples by radiochemical activation analysis

International Nuclear Information System (INIS)

Reisell, A.; Lakomaa, E.L.

1983-03-01

A radiochemical neutron activation analysis method for the determination of chromium, cobalt and nickel in tissue samples. A radiochemical neutron activation analysis method for the determination of chromium, cobalt and nickel has been developed. The destruction device used consisted of a combined wet-ashing-distillation and ion-exchange system. Six samples could be treated at the same time. The samples were wet-ashed with H*L2SO*L4-H*L2O*L2 mixture. Volatile elements were distilled as bromide compounds with HBr*H-. The distillation residue in 8M HCl was passed through hydrated antimony pentoxide (HAP) in order to remove disturbing *H2*H4Na-activity and through a Dowex 2 x 8 column so as to retain *H6*H0Co (formed from *H5*H8Ni). Chromium was elutriated from the column and precipitated as Cr(OH)*L3 for the removal of disturbing *H3*H2P-activity. The standards and samples were treated in a similar manner each so that the yield determination is not necessarily needed. The yields by tracer experiments were (43 +- 5) % for Cr, (93 +- 4) % for Co and (88 +- 14) % for Ni. The precision and accuracy of the method were studied by using reference materials of the National Bureau of Standards (NBS) and the International Atomic Energy Agency (IAEA)

The Protein-Sparing Modified Fast Diet

Directory of Open Access Journals (Sweden)

Marwan Bakhach MD

2016-01-01

Full Text Available Objectives: The protein-sparing modified fast (PSMF is a rigorous way of rapidly losing a large amount of weight. Although adult studies have shown the PSMF to be effective, data in adolescents are lacking. The aim of this study was to determine the efficacy and safety of the PSMF in severely obese adolescents. Methods: 12 subjects who were evaluated in the Obesity Management Program at the Cleveland Clinic from 2011 to 2014 were included. The subjects were initiated on the PSMF after failing other conventional methods of weight loss. Once the goal weight was achieved, subjects were transitioned to the refeeding phase for weight maintenance. Results: Follow-up was scheduled at 3-month (11 patients and 6-month (6 patients intervals. At the 6-month follow-up visit, the average weight loss was 11.19 kg (95% confidence interval = -5.4, -27.8, P = .028, with average of 9.8% from baseline. Fifty percent of subjects had >5% weight loss and 20% had >10% weight loss. Four patients were lost to the follow-up (40%. An improvement was noted in total cholesterol and high-density lipoprotein. Due to a small sample size these results were not statistically significant. Side effects reported by subjects were mild dehydration due to nausea (2 patients, decreased energy (1 patient, and transient labile mood (1 patient. No life-threatening side effects were reported. Conclusion: Our results show that the PSMF diet can be used as an effective and safe method in the outpatient setting for rapid weight loss in adolescents with severe obesity.

The design of a new radiochemical laboratory complex

International Nuclear Information System (INIS)

Lewis, A.G.

1984-01-01

A brief account is given of the history and scope of Amersham International plc in the manufacture of radiopharmaceuticals and other labelled organic compounds, and radioactive sources. Extra facilities were needed and a new site was found, and contracts placed for new radiochemical laboratories. The two new laboratories, which are described in some detail, are intended as follows: (a) a Medical Products building for the production of a range of diagnostic kits for use in the treatment of thyroid and other disorders, the main isotope used being iodine-125; and (b) the Chemical Products building, for the development and manufacture of a wide range of organic compounds, which are labelled with either tritium or carbon-14. Particular emphasis is given to the description of the air conditioning and ventilation systems, the open work benches, and the special ventilated enclosures, and the drainage system. Planning for maximum flexibility is also stressed. (U.K.)

The radiochemical purity of radiotracers as the criterion of their usefulness in investigations of hydrocarbons distillation

International Nuclear Information System (INIS)

Kolaczkowski, M.

1976-01-01

Among numerous analytic techniques of separation and analysis of radioactive products gas radiochromatography has proved to be particularly suitable. Organic bromides labelled with 82 Br-radionuclide are investigated. The analytic gas chromatographs equipped with appropriately constructed radiochromatographic attachments are used. The results of radiochemical purity determination of radiotracers are compared for various techniques. (author)

The mechanism of lauric acid-modified protein nanocapsules escape from intercellular trafficking vesicles and its implication for drug delivery.

Science.gov (United States)

Jiang, Lijuan; Liang, Xin; Liu, Gan; Zhou, Yun; Ye, Xinyu; Chen, Xiuli; Miao, Qianwei; Gao, Li; Zhang, Xudong; Mei, Lin

2018-11-01

Protein nanocapsules have exhibited promising potential applications in the field of protein drug delivery. A major issue with various promising nano-sized biotherapeutics including protein nanocapsules is that owing to their particle size they are subject to cellular uptake via endocytosis, and become entrapped and then degraded within endolysosomes, which can significantly impair their therapeutic efficacy. In addition, many nano-sized biotherapeutics could be also sequestered by autophagosomes and degraded through the autolysosomal pathway. Thus, a limiting step in achieving an effective protein therapy is to facilitate the endosomal escape and auto-lysosomal escape to ensure cytosolic delivery of the protein drugs. Here, we prepared a protein nanocapsule based on BSA (nBSA) and the BSA nanocapsules modified with a bilayer of lauric acid (LA-nBSA) to investigate the escape effects from the endosome and autophagosome. The size distribution of nBSA and LA-nBSA analyzed using DLS presents a uniform diameter centered at 10 nm and 16 nm. The data also showed that FITC-labeled nBSA and LA-nBSA were taken up by the cells mainly through Arf-6-dependent endocytosis and Rab34-mediated macropinocytosis. In addition, LA-nBSA could efficiently escape from endosomal before the degradation in endo-lysosomes. Autophagy could also sequester the LA-nBSA through p62 autophagosome vesicles. These two types of nanocapsules underwent different intracellular destinies and lauric acid (LA) coating played a vital role in intracellular particle retention. In conclusion, the protein nanocapsules modified with LA could enhance the protein nanocapsules escape from intercellular trafficking vesicles, and protect the protein from degradation by the lysosomes.

Study of performance characteristics of a radiochemical method to determine uranium in biological samples

International Nuclear Information System (INIS)

Puga, Maria J.; Cerchietti, Maria L.R.; Prudenzo, J.E.; Arguelles, Maria G.

2005-01-01

In this paper is described a methodology to calculate detection limit (Ld), quantification level (Lq) and minimum detectable activity (MDA) in a radiochemical method for determination of uranium in urine samples. The concentration is measured by fluorimetry and alpha gross activity using liquid scintillation counting (LSC). The calculation of total propagated uncertainty on a spike sample is presented. Furthermore, the major sources of uncertainty and percentage contribution in both measurements are assessed. (author)

Determination of heavy metal pollutants such as Hg, Zn, Se, Cd, and Cu in aquatic environment of Thana Creek by radiochemical thermal neutron activation analysis

International Nuclear Information System (INIS)

khan, S.Z.; Shah, P.K.; Ramani Rao, V.; Turel, Z.r.; Haldar, B.C.

1984-01-01

A rapid method has been developed for the radiochemical separation of Cu, As, Se, Hg, and Zn from thermal neutron irradiated environmental samples. The concentration of the elements in the environmental samples has been ascertained by radiochemical neutron activation analysis. The accuracy, precision and sensitivity of the method has been determined. The results of the analysis indicates the location of maximum pollution of the aquatic environment and the extent of pollution in the 5 locations of Thana Creek. 1 reference, 3 tables

Use of 236Pu and 242Pu as a radiochemical tracer for estimation of Pu in bioassay samples by fission track analysis

International Nuclear Information System (INIS)

Sawant, Pramilla D.; Prabhu, Supreetha P.; Kalsi, P.C.

2008-01-01

236 Pu and 242 Pu are routinely used as radiochemical yield monitors in India for bioassay monitoring of occupational workers by alpha spectrometry. Fission Track Analysis (FTA) is also being standardized for trace level determination of Pu in bioassay samples. The present study, reports the utility of 236 Pu and 242 Pu as radiochemical tracers in estimation of Pu in bioassay samples by FTA technique. The advantages of using 236 Pu tracer in FTA over 242 Pu as well as the interference caused due to presence of 241 Pu in the bioassay samples of occupational workers handling power reactor grade Pu is discussed. (author)

A thiophene-modified screen printed electrode for detection of dengue virus NS1 protein.

Science.gov (United States)

Silva, M M S; Dias, A C M S; Cordeiro, M T; Marques, E; Goulart, M O F; Dutra, R F

2014-10-01

A thiophene-modified screen printed electrode (SPE) for detection of the Dengue virus non-structural protein 1 (NS1), an important marker for acute phase diagnosis, is described. A sulfur-containing heterocyclic compound, the thiophene was incorporated to a carbon ink to prepare reproducible screen printed electrodes. After cured, the thiophene SPE was coated by gold nanoparticles conjugated to Protein A to form a nanostrutured surface. The Anti-NS1 antibodies immobilized via their Fc portions via Protein A, leaving their antigen specific sites free circumventing the problem of a random antibodies immobilization. Amperometric responses to the NS1 protein of dengue virus were obtained by cyclic voltammetries performed in presence of ferrocyanide/ferricyanide as redox probe. The calibration curve of immunosensor showed a linear response from 0.04 µg mL(-1) to 0.6 µg mL(-1) of NS1 with a good linear correlation (r=0.991, pink enhanced the electroanalytical properties of the SPEs, increasing their reproducibility and sensitivity. This point-of-care testing represents a great potential for use in epidemic situations, facilitating the early diagnosis in acute phase of dengue virus. Copyright © 2014 Elsevier B.V. All rights reserved.

Hydrologic conditions and distribution of selected radiochemical and chemical constituents in water, Snake River Plain aquifer, Idaho National Engineering Laboratory, Idaho, 1992 through 1995

International Nuclear Information System (INIS)

Bartholomay, R.C.; Tucker, B.J.; Ackerman, D.J.; Liszewski, M.J.

1997-04-01

Radiochemical and chemical wastewater discharged since 1952 to infiltration ponds and disposal wells at the Idaho National Engineering Laboratory (INEL) has affected water quality in the Snake River Plain aquifer. The US Geological Survey, in cooperation with the US Department of Energy, maintains a monitoring network at the INEL to determine hydrologic trends and to delineate the movement of radiochemical and chemical wastes in the aquifer. This report presents an analysis of water-level and water-quality data collected from the Snake River Plain aquifer during 1992--95

A radiochemical NAA method for the determination of tin, barium, copper and antimony- role of tin as an indicator for gun shot residues

International Nuclear Information System (INIS)

Chattopadhyay, N.; Basu, A.K.; Tripathi, A.B.R.; Rao, M.S.; Anil Kumar, S.; Parthasarathy, R.; Mathur, P.K.

1998-01-01

Metallic tin being present as impurity and hardening agent of lead bullet/shot, is expected to play an important role in forensic ballistics in matching of bullet lead specimens for establishment of commonness of origin and also as an additional parameter for characterisation of Gun Shot Residue (GSR). 121 Sn is a suitable radioisotope for quantification of the element at ppm level if it is separated in highest radiochemical purity. A sequential Radiochemical Neutron Activation Analysis (RNAA) procedure for its simultaneous determination along with trace levels of Ba, Cu and Sb has been developed and its applications in forensic science are described. (author)

Negligible depletion solid-phase microextraction with radiolabeled analytes to study free concentrations and protein binding : an example with [3H]Estradiol

NARCIS (Netherlands)

Heringa, M.B.; Pastor, D.; Algra, J.; Vaes, W.H.J.; Hemmens, J.L.M.

2002-01-01

A new method is presented that enables sensitive measurement of free concentrations of radiolabeled ligands. Additionally, protein binding of radiochemicals in complex matrixes can be determined with this new technique that combines negligible depletion solid-phase microextraction (nd-SPME) with

A new radiochemical assay for fructose-1,6-diphosphatase in human leucocytes

International Nuclear Information System (INIS)

Janssen, A.J.M.; Trijbels, F.J.M.

1982-01-01

Fructose-1,6-diphosphatase (D-fructose-1,6-diphosphate 1-phosphohydrolase, EC 3.1.3.11, FDPase) is one of the key enzymes of the gluconeogenic pathway. Measuring the activity both in the presence and in the absence of AMP yields the true FDPase activity, corrected for non-specific phosphatase activity. In this paper the authors introduce a new radiochemical assay for FDPase, based on the decarboxylating activity of 6-phosphogluconate dehydrogenase. One molecule [U- 14 C]fructose-1,6-diphosphate yields one molecule 14 CO 2 which can be captured in strongly basic solutions and counted in a liquid scintillation counter. (Auth.)

Radiochemical measurement of mass transport in sodium

International Nuclear Information System (INIS)

Cooper, M.H.; Chiang, S.H.

1976-01-01

Mass transport processes in the sodium coolant of Liquid Metal Fast Breeder Reactors (LMFBRs) are significant in determining rates of corrosion and deposition of radioactive nuclides from the fuel cladding, deposition and cold trapping of fission products from defect or failed fuel, carbon and nitrogen redistribution in the containment materials, and removal of impurities by cold trapping or hot trapping. Mass transport between rotating, concentric cylinders in molten sodium has been investigated using a unique radiochemical method. Long-lived (33 year) cesium-137, dissolved in the sodium, decays radioactively emitting a beta to barium-137m, which decays with a short half-life (2.6 minutes) emitting a gamma. Cesium is weakly adsorbed and remains in solution, while the barium is strongly adsorbed on the stainless steel surfaces. Hence, by measuring the barium-137m activity on movable stainless steel surfaces, one can calculate the mass transport to that surface. Mass transfer coefficients in sodium measured by this method are in agreement with published heat transfer correlations when the effect of the volumetric mass source is taken into account. Hence, heat transfer correlations can be confidently utilized by analogy in estimating mass transfer in liquid-metal systems

Roles of Trm9- and ALKBH8-like proteins in the formation of modified wobble uridines in Arabidopsis tRNA

DEFF Research Database (Denmark)

Leihne, Vibeke; Kirpekar, Finn; Vågbø, Cathrine B

2011-01-01

Uridine at the wobble position of tRNA is usually modified, and modification is required for accurate and efficient protein translation. In eukaryotes, wobble uridines are modified into 5-methoxycarbonylmethyluridine (mcm(5)U), 5-carbamoylmethyluridine (ncm(5)U) or derivatives thereof. Here, we...... demonstrate, both by in vitro and in vivo studies, that the Arabidopsis thaliana methyltransferase AT1G31600, denoted by us AtTRM9, is responsible for the final step in mcm(5)U formation, thus representing a functional homologue of the Saccharomyces cerevisiae Trm9 protein. We also show that the enzymatic...... activity of AtTRM9 depends on either one of two closely related proteins, AtTRM112a and AtTRM112b. Moreover, we demonstrate that AT1G36310, denoted AtALKBH8, is required for hydroxylation of mcm(5)U to (S)-mchm(5)U in tRNA(Gly)(UCC), and has a function similar to the mammalian dioxygenase ALKBH8...

Isolation of a macrophage receptor for proteins modified by advanced glycosylation end products

International Nuclear Information System (INIS)

Radoff, S.; Vlassara, H.; Cerami, A.

1987-01-01

The nonenzymatic reaction of glucose with protein amino groups leads to the formation of irreversible AGE, such as the recently characterized glucose-derived crosslink, [2-furoyl-4(5)-(2-furanyl)-1-H-imidazole] (FFI). These products accumulate with time in aging tissues and diabetes, and are implicated in irreversible tissue damage. The authors have recently shown that macrophages bind and degrade AGE-proteins via a specific surface receptor, which is thus selectively removing senescent macromolecules. Scatchard plot analysis of binding data has indicated 1.5 x 10 5 receptors/cell with a binding affinity (Ka) of 1.7 x 10 7 /M. They have now isolated this receptor from murine macrophage RAW 264.7 membranes, solubilized with octylglucoside/protease inhibitors, and using FFI-Sepharose affinity chromatography and FPLC. The purified receptor binds radioactive FFI-containing compounds competitively. SDS-PAGE gels under reducing conditions indicate the receptor to be composed of two polypeptides, 83 Kda and 36 Kda. Crosslinking experiments with 125 I-AGE-albumin as ligand, indicate the 83 Kda subunit to be the AGE-binding peptide. These studies further characterize a macrophage receptor which selectively recognizes time-dependent glucose-modified proteins associated with aging and diabetes

Fractionation of Cardiolite for clinical use: comparative evaluation of radiochemical purity by thin-layer and paper chromatography of 99mTc-hexakis-2-methoxy-isobutyl-isonitrile complex

International Nuclear Information System (INIS)

Albernaz, M.S.; Pantoja, M.R.; Martinho, M.J.R.; Fonseca, M.L.B.; Bernardo-Filho, Mario

1996-01-01

Twenty-five vials of the previous divided Cardiolite (technetium-99m-hexakis-2-metoxi-isobutyl-isonitrile) were evaluated immediately after labeling with technetium-99m and in 15 them the specific activity assurance was checked at hourly intervals up to 3 hours. Quality control assessment comprised instant thin-layer chromatography, as suggested by the manufacturer, compared to paper chromatography which is widely available and less expensive than the former. Among the 25 bottles, 21 had a radiochemical purity higher than 89%. The redistribution of the Cardiolite in small doses vacuum containers was a practical and reliable technique. The technetium-99m-isonitrile was a stable radiochemical compound thought the three hours period of observation and proved adequate for clinical use. When thin-layer and paper chromatography were compared there was no significant difference regarding radiochemical purity. (author)

Validation of the FDG (18F) radiochemical purity assay by thin layer chromatography

International Nuclear Information System (INIS)

Leao, R.L.C.; Oliveira, M.L.; Nascimento, J.E.; Nascimento, N.C.E.S.

2013-01-01

All methodologies utilized in radiopharmaceutical industry should be validated in order to prove that they meet the requirements of analytical applications, ensuring the reliability of the results. At a radiopharmaceutical industry there is one challenge aspect: sometimes it is not possible use a stable standard to perform the validation analysis. In order to overcome this difficulty, the objective of this study was to suggest a validation protocol for these methodologies, based on the recommendations of RE n° 899/Agencia Nacional de Vigilancia Sanitaria (ANVISA), and prove its efficiency, performing the radiochemical purity validation test of FDG (18F), by TLC. To obtain the calibration curve, we suggested that the theoretical activity values should be determined using a dose calibrator, simultaneously of each analysis performed by TLC, for 5 hours. The method was linear (R 2 of 0.996), precise (CV% <5%) and accurate (96.85% < accuracy < 102.56%). In relation to the robustness test, our experiments evaluated the influence of the distance travelled by mobile phase, variations at mobile phase concentration and type of chromatographic plate (silica gel on glass or aluminium plates). The detection and quantification limits were determined (321.9 and 1065.6 kBq, respectively). As expected, this methodology was nonspecific, showing a slight spot corresponding to the FDM. The proposed protocol was efficient and the methodology tested was effective to determine the radiochemical purity of FDG (18F), in accordance to the limits recommended by ANVISA. (author)

Synthesis of 17α-[(E)-2-[125I]iodoethenyl]androsta-4-6-dien-17β-o l-3-one, an active -site-directed photoaffinity radiolabel for androgen-binding proteins

International Nuclear Information System (INIS)

Diaz Cruz, P.J.; Smith, H.E.; Vanderbilt Univ., Nashville, TN; Danzo, B.J.; Clanton, J.A.; Mason, N.S.

1993-01-01

The active-site-directed photoaffinity radiolabel for androgen-binding proteins, 17α-[(E)-2-[ 125 I]iodoethenyl]androsta-4,6-dien-17β-ol-3-one, was prepared by reaction of 17α-[(E)-2-tributyltin(IV)ethenyl]androsta-4,6-dien-17β-ol-3-one with carrier added sodium iodide-125 in the presence of hydrogen peroxide and acetic acid. Purification by HPLC gave the radiolabeled steroid in 52% radiochemical yield with a specific activity of 27 Ci/mmol and 100% radiochemical purity. (author)

Middle east respiratory syndrome coronavirus spike protein delivered by modified vaccinia virus ankara efficiently induces virus-neutralizing antibodies

NARCIS (Netherlands)

F. Song (Fei); R. Fux (Robert); L.B.V. Provacia (Lisette); A. Volz (Asisa); M. Eickmann; S. Becker (Stephan); A.D.M.E. Osterhaus (Albert); B.L. Haagmans (Bart); G. Suttera (Gerd)

2013-01-01

textabstractMiddle East respiratory syndrome coronavirus (MERS-CoV) has recently emerged as a causative agent of severe respiratory disease in humans. Here, we constructed recombinant modified vaccinia virus Ankara (MVA) expressing full-length MERS-CoV spike (S) protein (MVA-MERS-S). The genetic

Radiochemical neutron activation analysis of zirconium and zirconium-niobium alloys

International Nuclear Information System (INIS)

Tashimova, F.A.; Sadikov, I.I.; Salimov, M.

2004-01-01

Full text: Zirconium and zirconium-niobium alloys are used on nuclear technology, as fuel cladding of nuclear reactors. Their nuclear-physical, mechanical and thermophysical properties are influenced them matrix and impurity composition, therefore determination of matrix and impurity content of these materials is a very important task. Neutron activation analysis is one from multielemental and high sensible techniques that are widely applied in analysis of high purity materials. Investigation of nuclear-physical characteristics of zirconium has shown that instrumental variant NAA is unusable for analysis due to high radioactivity of a matrix. Therefore it is necessary carrying out radiochemical separation of impurity radionuclides from matrix. Study of the literature datum have shown, that zirconium and niobium are very well extracted from muriatic solution with 5% tributyl phosphineoxide (TBPO) solution in toluene and 0,75 M solution of di-2-ethyl hexyl phosphoric acid (HDEHP) in cyclohexanone. Investigation of these elements extraction in these systems has shown that more effective and selective separation of matrix radionuclides is achieved in HDEHP-3M HCI system. This system is also extracted and hafnium, witch is an accompanying element of zirconium and its high content prevented determination of other impurity elements in sample. Therefore we used extraction system HDEHP-3M HCl for analysis of zirconium and zirconium-niobium alloys in chromatographic variant. By measurement of distribution profile of a matrix and of elution curve of determined elements is established, that for effective separation of impurity and matrix radionuclides there is enough chromatographic column with diameter 1 cm and height of a sorbent layer 7 cm, thus volume of elute, necessary for complete elution of determinate elements is 35-40 ml. On the basis of the carried out researches the technique of radiochemical NAA of high purity zirconium and zirconium-niobium alloy, which allows to

Colon luminal content and epithelial cell morphology are markedly modified in rats fed with a high-protein diet

OpenAIRE

Andriamihaja, Mireille; Davila-Gay, Anne-Marie; Eklou, Mamy; Petit, Nathalie; Delpal, Serge; Allek, Fadhila; Blais, Anne; Delteil, Corine; Tomé, Daniel; Blachier, Francois

2010-01-01

Andriamihaja M, Davila A, Eklou-Lawson M, Petit N, Delpal S, Allek F, Blais A, Delteil C, Tome D, Blachier F. Colon luminal content and epithelial cell morphology are markedly modified in rats fed with a high-protein diet. Am J Physiol Gastrointest Liver Physiol 299: G1030-G1037, 2010. First published August 5, 2010; doi: 10.1152/ajpgi.00149.2010.-Hyperproteic diets are used in human nutrition to obtain body weight reduction. Although increased protein ingestion results in an increased transf...

N(epsilon)-carboxymethyllysine-modified proteins are unable to bind to RAGE and activate an inflammatory response.

Science.gov (United States)

Buetler, Timo M; Leclerc, Estelle; Baumeyer, Alexandra; Latado, Helia; Newell, John; Adolfsson, Oskar; Parisod, Véronique; Richoz, Janique; Maurer, Sarah; Foata, Francis; Piguet, Dominique; Junod, Sylviane; Heizmann, Claus W; Delatour, Thierry

2008-03-01

Advanced glycation endproducts (AGEs) containing carboxymethyllysine (CML) modifications are generally thought to be ligands of the receptor for AGEs, RAGEs. It has been argued that this results in the activation of pro-inflammatory pathways and diseases. However, it has not been shown conclusively that a CML-modified protein can interact directly with RAGE. Here, we have analyzed whether beta-lactoglobulin (bLG) or human serum albumin (HSA) modified chemically to contain only CML (10-40% lysine modification) can (i) interact with RAGE in vitro and (ii) interact with and activate RAGE in lung epithelial cells. Our results show that CML-modified bLG or HSA are unable to bind to RAGE in a cell-free assay system (Biacore). Furthermore, they are unable to activate pro-inflammatory signaling in the cellular system. Thus, CML probably does not form the necessary structure(s) to interact with RAGE and activate an inflammatory signaling cascade in RAGE-expressing cells.

Quantitative radio-chemical separation of calcium, strontium and barium

International Nuclear Information System (INIS)

Dupuis, M.C.; Dupuis, M.; Le Nagard, M.; Michot, H.

1965-01-01

A method for separation of Ca 45 , Sr 89 and Ba 140 has been developed for the radiochemical determination of these isotopes in a solution of fission with a large concentration of mineral salts. After removal of most fission products by solvent extraction (TTA-MIBK) at different pH, the alkaline earths are extracted from the aqueous phase at pH 9. After recovery with diluted hydrochloric acid, the three elements are adsorbed on cationic resin Dowex 50 and eluted sequentially with ammonium α - Hydroxy iso-butyrate using gradient concentration and pH. Ca 45 and Sr 89 are measured by β - counting and Ba 140 by γ spectrometry. The chemical yield approximates 80 per cent for calcium, and 70 per cent for strontium and barium. The decontamination factor is 10 5 for most fission products. Four separations can be performed in twenty hours. (authors) [fr

Pepsin immobilized in dextran-modified fused-silica capillaries for on-line protein digestion and peptide mapping

Energy Technology Data Exchange (ETDEWEB)

Stigter, E.C.A. [Division of Biomedical Analysis, Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands)], E-mail: e.c.a.stigter@uu.nl; Jong, G.J. de; Bennekom, W.P. van [Division of Biomedical Analysis, Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands)

2008-07-07

On-line digestion of proteins under acidic conditions was studied using micro-reactors consisting of dextran-modified fused-silica capillaries with covalently immobilized pepsin. The proteins used in this study differed in molecular weight, isoelectric point and sample composition. The injected protein samples were completely digested in 3 min and the digest was analyzed with micro-high performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). The different proteins present in the samples could be identified with a Mascot database search on the basis of auto-MS/MS data. It proved also to be possible to digest and analyze protein mixtures with a sequence coverage of 55% and 97% for the haemoglobin {beta}- and {alpha}-chain, respectively, and 35-55% for the various casein variants. Protease auto-digestion, sample carry-over and loss of signal due to adsorption of the injected proteins were not observed. The backpressure of the reactor is low which makes coupling to systems such as Surface Plasmon Resonance biosensors, which do not tolerate too high pressure, possible. The reactor was stable for at least 40 days when used continuously.

Pepsin immobilized in dextran-modified fused-silica capillaries for on-line protein digestion and peptide mapping.

Science.gov (United States)

Stigter, E C A; de Jong, G J; van Bennekom, W P

2008-07-07

On-line digestion of proteins under acidic conditions was studied using micro-reactors consisting of dextran-modified fused-silica capillaries with covalently immobilized pepsin. The proteins used in this study differed in molecular weight, isoelectric point and sample composition. The injected protein samples were completely digested in 3 min and the digest was analyzed with micro-high performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). The different proteins present in the samples could be identified with a Mascot database search on the basis of auto-MS/MS data. It proved also to be possible to digest and analyze protein mixtures with a sequence coverage of 55% and 97% for the haemoglobin beta- and alpha-chain, respectively, and 35-55% for the various casein variants. Protease auto-digestion, sample carry-over and loss of signal due to adsorption of the injected proteins were not observed. The backpressure of the reactor is low which makes coupling to systems such as Surface Plasmon Resonance biosensors, which do not tolerate too high pressure, possible. The reactor was stable for at least 40 days when used continuously.

Paleomagnetism and radiochemical age estimates for Late Brunhes polarity episodes

International Nuclear Information System (INIS)

Denham, C.R.; Anderson, R.F.; Bacon, M.P.

1977-01-01

Several reversed polarity magnetozones occur within deep-sea sediment core CH57-8 from the Greater Antilles Outer Ridge, within sediment of latest Pleistocene/Late Brunhes age. The uppermost reversed interval spanning 31 data points coincides with the X faunal zone of the Last Interglacial Period. Radiochemical dating of cores CH57-8 and KN25-4 has shown that all the reversed polarity magnetozones are significantly younger than the Brunhes/Matuyama boundary at 0.7 m.y.B.P. A variation of the excess 230 Th method was used, in which 210 Po and 238 U were the actual radionuclides measured. In a third core from the Mid-Atlantic Ridge, the 210 Po results were similar to those which others obtained earlier by direct 230 Th measurements. (Auth.)

Research reactor FR2 - 20 years chemical and radiochemical measurements

International Nuclear Information System (INIS)

Feuerstein, H.; Graebner, H.; Oschinski, J.; Hoffmann, W.; Beyer, J.

1986-09-01

The FR2 has been a D 2 O cooled and moderated research reactor with a thermal output of 44 MW. It was in operation from 1961 to 1981. Because of the operating conditions of the reactor, only a small number of routine measurements were performed. For these however special techniques had to be developed. During the 20 years of operation a number of special events occured or have been observed, sometimes with very amazing results, e.g. the 'aceton effect'. This report describes the chemical and radiochemical conditions of the reactor systems, as well as the results of the surveilance work. Not described are measurements for the many experiments. The last chapter gives in a short form a description of the most unusual events and observations. (orig.) [de

Determination of selenium in roasted beans coffee samples consumed in Algeria by radiochemical neutron activation analysis method

International Nuclear Information System (INIS)

Messaoudi, Mohammed; Begaa, Samir; Hamidatou, Lylia; Salhi, M'hamed

2018-01-01

The essential trace element selenium is a focus of attention due to its effects on human health, there being consequences of both its deficiency and excess. Due to the ultra-trace content of selenium, the neutron activation analysis method (NAA) is difficult to apply. We therefore made use of the radiochemical neutron activation analysis (RNAA) to determine Se at low level concentrations in several consumed food items in Algeria. A radiochemical procedure based on liquid-liquid separation was established in our laboratory. In this research we focused on the determination of selenium in two species of coffee: Arabica and Robusta. The accuracy of the method was assessed by analyzing the certified reference material NIST-SRM 1573a (tomato leaves). The results obtained show a selenium variation from 0.025 to 0.052 μg/g in coffee beans and an average yield of the separation of about 85%. The results of this study were compared with those obtained with samples from Brazilian, Caribbean, Indian and Kenyan coffee beans.

Dual Mode Fluorophore-Doped Nickel Nitrilotriacetic Acid-Modified Silica Nanoparticles Combine Histidine-Tagged Protein Purification with Site-Specific Fluorophore Labeling

OpenAIRE

Kim, Sung Hoon; Jeyakumar, M.; Katzenellenbogen, John A.

2007-01-01

We present the first example of a fluorophore-doped nickel chelate surface- modified silica nanoparticle that functions in a dual mode, combining histidine-tagged protein purification with site-specific fluorophore labeling. Tetramethylrhodamine (TMR)-doped silica nanoparticles, estimated to contain 700–900 TMRs per ca. 23-nm particle, were surface modified with nitrilotriacetic acid (NTA), producing TMR-SiO2-NTA-Ni+2. Silica-embedded TMR retains very high quantum yield, is resistant to quenc...

NMR-based approach to the analysis of radiopharmaceuticals: radiochemical purity, specific activity, and radioactive concentration values by proton and tritium NMR spectroscopy.

Science.gov (United States)

Schenk, David J; Dormer, Peter G; Hesk, David; Pollack, Scott R; Lavey, Carolee Flader

2015-06-15

Compounds containing tritium are widely used across the drug discovery and development landscape. These materials are widely utilized because they can be efficiently synthesized and produced at high specific activity. Results from internally calibrated (3)H and (1)H nuclear magnetic resonance (NMR) spectroscopy suggests that at least in some cases, this calibrated approach could supplement or potentially replace radio-high-performance liquid chromatography for radiochemical purity, dilution and scintillation counting for the measurement of radioactivity per volume, and liquid chromatography/mass spectrometry analysis for the determination of specific activity. In summary, the NMR-derived values agreed with those from the standard approaches to within 1% to 9% for solution count and specific activity. Additionally, the NMR-derived values for radiochemical purity deviated by less than 5%. A benefit of this method is that these values may be calculated at the same time that (3)H NMR analysis provides the location and distribution of tritium atoms within the molecule. Presented and discussed here is the application of this method, advantages and disadvantages of the approach, and a rationale for utilizing internally calibrated (1)H and (3)H NMR spectroscopy for specific activity, radioactive concentration, and radiochemical purity whenever acquiring (3)H NMR for tritium location. Copyright © 2015 John Wiley & Sons, Ltd.

Electrochemical immunosensors for the detection of survival motor neuron (SMN) protein using different carbon nanomaterials-modified electrodes.

Science.gov (United States)

Eissa, Shimaa; Alshehri, Nawal; Rahman, Anas M Abdel; Dasouki, Majed; Abu-Salah, Khalid M; Zourob, Mohammed

2018-03-15

Spinal muscular atrophy is an untreatable potentially fatal hereditary disorder caused by loss-of-function mutations in the survival motor neuron (SMN) 1 gene which encodes the SMN protein. Currently, definitive diagnosis relies on the demonstration of biallelic pathogenic variants in SMN1 gene. Therefore, there is an urgent unmet need to accurately quantify SMN protein levels for screening and therapeutic monitoring of symptomatic newborn and SMA patients, respectively. Here, we developed a voltammetric immunosensor for the sensitive detection of SMN protein based on covalently functionalized carbon nanofiber-modified screen printed electrodes. A comparative study of six different carbon nanomaterial-modified electrodes (carbon, graphene (G), graphene oxide (GO), single wall carbon nanotube (SWCNT), multi-wall carbon nanotube (MWCNT), and carbon nanofiber (CNF)) was performed. 4-carboxyphenyl layers were covalently grafted on the six electrodes by electroreduction of diazonium salt. Then, the terminal carboxylic moieties on the electrodes surfaces were utilized to immobilize the SMN antibody via EDC/NHS chemistry and to fabricate the immunosensors. The electrochemical characterization and analytical performance of the six immunosensors suggest that carbon nanofiber is a better electrode material for the SMN immunosensor. The voltammetric SMN carbon nanofiber-based immunosensor showed high sensitivity (detection limit of 0.75pg/ml) and selectivity against other proteins such as cystic fibrosis transmembrane conductance regulator (CFTR) and dystrophin (DMD). We suggest that this novel biosensor is superior to other developed assays for SMN detection in terms of lower cost, higher sensitivity, simplicity and capability of high throughput screening. Copyright © 2017 Elsevier B.V. All rights reserved.

Synthesis of [¹¹C]PBR170, a novel imidazopyridine, for imaging the translocator protein with PET.

Science.gov (United States)

Bourdier, Thomas; Henderson, David; Fookes, Christopher J R; Lam, Peter; Mattner, Filomena; Fulham, Michael; Katsifis, Andrew

2014-08-01

The translocator protein (TSPO) ligand 2-(6,8-dichloro-2-(4-ethoxyphenyl)imidazo[1,2-a]pyridin-3-yl)-N-(2-fluoropyridin-3-yl)-N-methylacetamide (PBR170), is a novel imidazopyridineacetamide with high affinity (2.6 nm) and selectivity for the TSPO. The synthesis of [(11)C]PBR170 was accomplished by N-methylation of the corresponding desmethyl precursor with [(11)C]methyl iodide in the presence of sodium hydroxide in dimethylformamide. [(11)C]PBR170 was produced in 30-45% radiochemical yield (decay-corrected, based on [(11)C]methyl iodide) with a radiochemical purity >98% and a specific activity of 90-190 GBq/μmol after 35 min of synthesis time. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Direct and indirect radioiodination of protein: comparative study of chemotactic peptide labeling

International Nuclear Information System (INIS)

Lavinas, Tatiana

2004-01-01

The development of simple methods for protein radioiodination have stimulated the use of radioiodinated peptides in vivo. There are two basic methods for labeling proteins with radioiodine: direct labeling, reaction of an electrophilic radioiodine with functional activated groups on protein, like the phenol ring in the tyrosine residue, and the conjugation of a previously radioiodinated molecule to the protein, referred as indirect method. The great problem related to the direct radioiodination of proteins is the in vivo dehalogenation. This problem can be minimized if a non-phenolic prosthetic group is used in the indirect radioiodination of the peptide. The ATE prosthetic group, N-succinimidyl 3-(tri-n-butylstannyl) benzoate, when radioiodinated by electrophilic iododestannilation produces N-succinimidyl 3-[ 123 l/ 131 l] iodine benzoate (SIB) that is subsequently conjugated to the protein by the acylation of the lysine group. There are many radiopharmaceuticals employed in scintigraphic images of infection and inflammation used with some limitations. These limitations stimulated the improvement of a new class of radiopharmaceuticals, the receptor-specific related labeled peptides, as the mediators of the inflammatory response, that presents high affinity by receptors expressed in the inflammation process, and fast clearance from blood and non-target tissues. One of these molecules is the synthetic chemotactic peptide fNleLFNIeYK that presents potent chemotaxis for leukocytes, with high affinity by the receptors presented in polymorphonuclear leukocytes and mononuclear phagocytes. The objective of this work included the synthesis of ATE prosthetic group and comparative radioiodination of the chemotactic peptide fNleLFNIeYK by direct and indirect methods, with radiochemical purity determination and evaluation of in vivo and in vitro stability of the compounds. This work presented an original contribution in the comparative biological distribution studies of the

Stationary and through-flow radiochemical detectors in cooperation with high performance liquid chromatography: Application in biochemistry

International Nuclear Information System (INIS)

Kehr, J.

1986-01-01

A review article is presented containing some original experimental data and discussing the usability of radiochemical detection of labelled compounds using high performance liquid chromatography. The stationary and through-flow types of detection are compared with respect to efficiency, chromatographic zone resolution, usability in biochemical research, and also to the current trends of development of liquid chromatography. (author). 3 figs., 1 tab., 19 refs

Formation of covalent linkages between nuclear and protein constituents of ribosomes of E. coli MRE 600 irradiated by gamma rays

Energy Technology Data Exchange (ETDEWEB)

Ekert, B; Giocanti, N [Institut du Radium, 91 - Orsay (France)

1977-04-01

Gamma irradiation of E.coli MRE 600 ribosomes in aqueous suspensions led to covalent linkages between the RNA and some ribosomal proteins. The presence of oxygen during the irradiation strongly inhibited this phenomenon. It appears clearly that only a few proteins were able to participate in these cross-linking reactions, which occurred simultaneously in the two sub-units. The radiochemical yield was determined at several concentrations and was relatively low.

Obtention process of phosphorus 32 starting from commercial sulfur and design and construction of the radiochemical separation prototype

International Nuclear Information System (INIS)

Duarte A, C.; Alanis M, J.; Gutierrez R, C.

2002-01-01

In this work an obtention process of phosphorus 32 ( 32 P) in orthophosphoric acid form (H 3 32 PO 4 ) is described starting from commercial sulfur. Also the design and construction of the experimental prototype used in the radiochemical separation and their results in three tests carried out is reported. (Author)

Identification and modulation of the key amino acid residue responsible for the pH sensitivity of neoculin, a taste-modifying protein.

Directory of Open Access Journals (Sweden)

Ken-ichiro Nakajima

Full Text Available Neoculin occurring in the tropical fruit of Curculigo latifolia is currently the only protein that possesses both a sweet taste and a taste-modifying activity of converting sourness into sweetness. Structurally, this protein is a heterodimer consisting of a neoculin acidic subunit (NAS and a neoculin basic subunit (NBS. Recently, we found that a neoculin variant in which all five histidine residues are replaced with alanine elicits intense sweetness at both neutral and acidic pH but has no taste-modifying activity. To identify the critical histidine residue(s responsible for this activity, we produced a series of His-to-Ala neoculin variants and evaluated their sweetness levels using cell-based calcium imaging and a human sensory test. Our results suggest that NBS His11 functions as a primary pH sensor for neoculin to elicit taste modification. Neoculin variants with substitutions other than His-to-Ala were further analyzed to clarify the role of the NBS position 11 in the taste-modifying activity. We found that the aromatic character of the amino acid side chain is necessary to elicit the pH-dependent sweetness. Interestingly, since the His-to-Tyr variant is a novel taste-modifying protein with alternative pH sensitivity, the position 11 in NBS can be critical to modulate the pH-dependent activity of neoculin. These findings are important for understanding the pH-sensitive functional changes in proteinaceous ligands in general and the interaction of taste receptor-taste substance in particular.

Radiochemical techniques for determining some naturally occurring radionuclides in marine environmental materials

Energy Technology Data Exchange (ETDEWEB)

Baker, C W [Ministry of Agriculture, Fisheries and Food, Lowestoft (UK). Fisheries Lab.

1984-06-15

The determination of some of the naturally-occurring, alpha-emitting radionuclides in marine environmental materials, is of interest for several reasons. Radium and radon nuclides are potentially useful as oceanographic tracers. Lead and thorium nuclides may be used to study sedimentation rates, mixing processes and bioturbation in sediments. Radium and polonium nuclides are incorporated into food chains and the data may provide a perspective against which to assess the significance, for marine organisms, of exposure to radiation in a marine radioactive waste disposal situation. This paper discusses the manner in which samples are taken, and the radiochemical methods which have been employed to measure the nuclides, together with some data produced.

Dual-mode fluorophore-doped nickel nitrilotriacetic acid-modified silica nanoparticles combine histidine-tagged protein purification with site-specific fluorophore labeling.

Science.gov (United States)

Kim, Sung Hoon; Jeyakumar, M; Katzenellenbogen, John A

2007-10-31

We present the first example of a fluorophore-doped nickel chelate surface-modified silica nanoparticle that functions in a dual mode, combining histidine-tagged protein purification with site-specific fluorophore labeling. Tetramethylrhodamine (TMR)-doped silica nanoparticles, estimated to contain 700-900 TMRs per ca. 23 nm particle, were surface modified with nitrilotriacetic acid (NTA), producing TMR-SiO2-NTA-Ni2+. Silica-embedded TMR retains very high quantum yield, is resistant to quenching by buffer components, and is modestly quenched and only to a certain depth (ca. 2 nm) by surface-attached Ni2+. When exposed to a bacterial lysate containing estrogen receptor alpha ligand binding domain (ERalpha) as a minor component, these beads showed very high specificity binding, enabling protein purification in one step. The capacity and specificity of these beads for binding a his-tagged protein were characterized by electrophoresis, radiometric counting, and MALDI-TOF MS. ERalpha, bound to TMR-SiO2-NTA-Ni++ beads in a site-specific manner, exhibited good activity for ligand binding and for ligand-induced binding to coactivators in solution FRET experiments and protein microarray fluorometric and FRET assays. This dual-mode type TMR-SiO2-NTA-Ni2+ system represents a powerful combination of one-step histidine-tagged protein purification and site-specific labeling with multiple fluorophore species.

Preparation of C-terminally modified chemokines by expressed protein ligation.

Science.gov (United States)

Baumann, Lars; Steinhagen, Max; Beck-Sickinger, Annette G

2013-01-01

In order to link structural features on a molecular level to the function of chemokines, site-specific modification strategies are strongly required. These can be used to incorporate fluorescent dyes and/or physical probes to allow investigations in a wide range of biological and physical techniques, e.g., nuclear magnetic resonance (NMR) spectroscopy, fluorescence microscopy, fluorescence resonance energy transfer (FRET), or fluorescence correlation spectroscopy (FCS). Only a limited number of functional groups within the 20 canonical amino acids allow ligation strategies that can be helpful to introduce novel functionalities, which in turn expand the scope of chemoselective and orthogonal reactivity of (semi)synthetic chemokines. In the present chapter we mainly focus on the fabulous history of native chemical ligation (NCL) and provide a general protocol for the preparation of C-terminally modified SDF-1α including tips and tricks for practical work. We believe that this protocol can be easily adapted to other chemokines and many proteins in general.

Computer aided design of piping for a radiochemical plant

Energy Technology Data Exchange (ETDEWEB)

Selvaraj, P G; Chandrasekhar, A; Chandrasekar, A V [Reprocessing Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India); Raju, R P; Mahudeeswaran, K V; Kumar, S V [Reprocessing Group, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

In a radiochemical plant such as reprocessing plants, process equipment, storage tanks, liquid transfer systems and the associated pipe lines etc. are housed in series of concrete cells. Availability of limited cell space/volume, provision of various modes of liquid transfers with associated redundancies and instrumentation lines with standby alternatives increase the overall piping density. Designing such high density piping layout without interference is quite complex and needs lot of human efforts. This paper briefly describes development of computer codes for the entire scheme of design, drafting and fabrication of piping for nuclear fuel reprocessing plant. The general organisation of various programs, their functions, the complete sequence of the scheme and the flow of data are presented. High degree of reliability of each routine, considerable error checking facilities, marking legends on the drawings, provision for scaling in drafting and accuracy to the extent of one mm in layout design are some of the important features of this scheme. (author). 1 fig.

Handling of Ammonium Nitrate Mother-Liquid Radiochemical Production - 13089

International Nuclear Information System (INIS)

Zherebtsov, Alexander; Dvoeglazov, Konstantine; Volk, Vladimir; Zagumenov, Vladimir; Zverev, Dmitriy; Tinin, Vasiliy; Kozyrev, Anatoly; Shamin, Dladimir; Tvilenev, Konstantin

2013-01-01

The aim of the work is to develop a basic technology of decomposition of ammonium nitrate stock solutions produced in radiochemical enterprises engaged in the reprocessing of irradiated nuclear fuel and fabrication of fresh fuel. It was necessary to work out how to conduct a one-step thermal decomposition of ammonium nitrate, select and test the catalysts for this process and to prepare proposals for recycling condensation. Necessary accessories were added to a laboratory equipment installation decomposition of ammonium nitrate. It is tested several types of reducing agents and two types of catalyst to neutralize the nitrogen oxides. It is conducted testing of modes of the process to produce condensation, suitable for use in the conversion of a new technological scheme of production. It is studied the structure of the catalysts before and after their use in a laboratory setting. It is tested the selected catalyst in the optimal range for 48 hours of continuous operation. (authors)

Fast analysis procedure of radiochemical coordinat uptake for methotrexate

International Nuclear Information System (INIS)

Caston, J.D.; Kamen, B.A.

1976-01-01

Under this invention, a radio-chemical analysis is submitted to determine the concentration of methotrexate or its equivalents in analysis in a biological medium. The amounts taken up of the labelled compound and the known concentrations of the unlabelled compound to be determined are radio-isotopically related to a first system containing a pre-determined amount of the labelled compound and a pre-determined amount of the unlabelled compound. In a second system, identical to the first, save that the sample of the biological medium to be analyzed takes the place of the unlabelled compound, the amount of labelled compound taken up is determined radio-isotopically. The concentration of the compound in the sample is then determined by correlation of the labelled compound uptake determined in the second system with the relation determined in the first system. The radio-isotopic relations and determinations may be made by direct and sequential analytical techniques [fr

The Role of Histone Protein Modifications and Mutations in Histone Modifiers in Pediatric B-Cell Progenitor Acute Lymphoblastic Leukemia

Science.gov (United States)

Janczar, Szymon; Janczar, Karolina; Pastorczak, Agata; Harb, Hani; Paige, Adam J. W.; Zalewska-Szewczyk, Beata; Danilewicz, Marian; Mlynarski, Wojciech

2017-01-01

While cancer has been long recognized as a disease of the genome, the importance of epigenetic mechanisms in neoplasia was acknowledged more recently. The most active epigenetic marks are DNA methylation and histone protein modifications and they are involved in basic biological phenomena in every cell. Their role in tumorigenesis is stressed by recent unbiased large-scale studies providing evidence that several epigenetic modifiers are recurrently mutated or frequently dysregulated in multiple cancers. The interest in epigenetic marks is especially due to the fact that they are potentially reversible and thus druggable. In B-cell progenitor acute lymphoblastic leukemia (BCP-ALL) there is a relative paucity of reports on the role of histone protein modifications (acetylation, methylation, phosphorylation) as compared to acute myeloid leukemia, T-cell ALL, or other hematologic cancers, and in this setting chromatin modifications are relatively less well studied and reviewed than DNA methylation. In this paper, we discuss the biomarker associations and evidence for a driver role of dysregulated global and loci-specific histone marks, as well as mutations in epigenetic modifiers in BCP-ALL. Examples of chromatin modifiers recurrently mutated/disrupted in BCP-ALL and associated with disease outcomes include MLL1, CREBBP, NSD2, and SETD2. Altered histone marks and histone modifiers and readers may play a particular role in disease chemoresistance and relapse. We also suggest that epigenetic regulation of B-cell differentiation may have parallel roles in leukemogenesis. PMID:28054944

Project Title: Radiochemical Analysis by High Sensitivity Dual-Optic Micro X-ray Fluorescence

International Nuclear Information System (INIS)

Havrilla, George J.; Gao, Ning

2002-01-01

A novel dual-optic micro X-ray fluorescence instrument will be developed to do radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford. This concept incorporates new X-ray optical elements such as monolithic polycapillaries and double bent crystals, which focus X-rays. The polycapillary optic can be used to focus X-rays emitted by the X-ray tube thereby increasing the X-ray flux on the sample over 1000 times. Polycapillaries will also be used to collect the X-rays from the excitation site and screen the radiation background from the radioactive species in the specimen. This dual-optic approach significantly reduces the background and increases the analyte signal thereby increasing the sensitivity of the analysis. A doubly bent crystal used as the focusing optic produces focused monochromatic X-ray excitation, which eliminates the bremsstrahlung background from the X-ray source. The coupling of the doubly bent crystal for monochromatic excitation with a polycapillary for signal collection can effectively eliminate the noise background and radiation background from the specimen. The integration of these X-ray optics increases the signal-to-noise and thereby increases the sensitivity of the analysis for low-level analytes. This work will address a key need for radiochemical analysis of high-level waste using a non-destructive, multi-element, and rapid method in a radiation environment. There is significant potential that this instrumentation could be capable of on-line analysis for process waste stream characterization at DOE sites

The radiochemical purity of technetium-99m-tin-diethylene-triamino-pentaacetic acid (DTPA) complex

International Nuclear Information System (INIS)

Besnard, M.; Costerousse, O.; Merlin, L.; Coehn, Y.

1975-01-01

The effect on radiochemical purity was studied as a function of the storage period of tin-DTPA solution and of the technetium-complex solution. The quantity of the pertechnetate ions present in the solution is determined by ascending paper chromatography, and an attempt was made to clarify the bond type of technetium by a spectrophotometric method. The tin-DTPA solutions for complexing of the reduced technetium are stable over a period of 8 weeks. The yield of the radiopharmaceutical product is better than 95%. (G.Gy.)

Radiochemical neutron activation analysis for trace elements evaluation of human milk

International Nuclear Information System (INIS)

Gill, K.P.; Zaidi, J.H.; Ahmad, S.

2003-01-01

The principal objective pursued in this study is to establish the base-line data on the status of elemental composition in human milk from Pakistani subjects of Rawalpindi/Islamabad area. Radiochemical neutron activation analysis (RNAA) methodology was developed and successfully employed to determine the concentration of 18 minor and trace elements (essential, toxic and nonessential) in human milk. This methodology has significantly improved the detection limits of most of these elements due to suppression of Compton background. The data provide the base-line values of these elements in human milk of low- and medium-income group subjects of the region. The results obtained show good compatibility with the data reported by the WHO on elemental composition of human milk from different geological regions. (orig.)

Chitosan scaffold modified with D-(+) raffinose and enriched with thiol-modified gelatin for improved osteoblast adhesion

International Nuclear Information System (INIS)

Galli, C; Parisi, L; Smerieri, A; Lumetti, S; Manfredi, E; Macaluso, G M; Elviri, L; Bianchera, A; Bettini, R; Lagonegro, P

2016-01-01

The aim of the present study was to investigate whether chitosan-based scaffolds modified with D-(+) raffinose and enriched with thiol-modified gelatin could selectively improve osteoblast adhesion and proliferation. 2, 3 and 4.5% chitosan films were prepared. Chitosan suitability for tissue engineering was confirmed by protein adsorption assay. Scaffolds were incubated with a 2.5 mg ml −1 BSA solution and the decrease of protein content in the supernatants was measured by spectrophotometry. Chitosan films were then enriched with thiol-modified gelatin and their ability to bind BSA was also measured. Then, 2% chitosan discs with or without thiol-modified gelatin were used as culture substrates for MC3T3-E1 cells. After 72 h cells were stained with trypan blue or with calcein AM and propidium iodide for morphology, viability and proliferation assays. Moreover, cell viability was measured at 48, 72, 96 and 168 h to obtain a growth curve. Chitosan films efficiently bound and retained BSA proportionally to the concentration of chitosan discs. The amount of protein retained was higher on chitosan enriched with thiol-modified gelatin. Moreover, chitosan discs allowed the adhesion and the viability of cells, but inhibited their proliferation. The functionalization of chitosan with thiol-modified gelatin enhanced cell spreading and proliferation. Our data confirm that chitosan is a suitable material for tissue engineering. Moreover, our data show that the enrichment of chitosan with thiol-modified gelatin enhances its biological properties. (paper)

Fast radiochemical procedure to measure neptunium, plutonium, americium and curium in environmental samples for application in environmental monitoring and in radioecology research

International Nuclear Information System (INIS)

Pimpel, M.; Schuettelkopf, H.

1984-01-01

A radiochemical method is described by which Np, Pu, Am and Cm in environmental samples can be determined. The transuranium elements are dissolved with acids out of the ashed material. Np/Pu is separated from Am/Cm by sequential extraction using TOPO/cyclohexane. The two fractions are radiochemically purified. Np-237, Pu-239+240, Pu-238 and Pu-236 as well as Am-243, Am-241, Cm-244 and Cm-242 are measured by alpha spectrometery. Pu-236, Am-243 and Np-239 are used to determine the respective yields. A fast method of Np-239 preparation is described. The chemical yields range from 60 to 90%. The detection limit attained per nuclide is 10 fCi/sample. 20 reference, 1 table

Development of robotic plasma radiochemical assays for positron emission tomography

International Nuclear Information System (INIS)

Alexoff, D.L.; Shea, C.; Fowler, J.S.; Gatley, S.J.; Schlyer, D.J.

1995-01-01

A commercial laboratory robot system (Zymate PyTechnology II Laboratory Automation System; Zymark Corporation, Hopkinton, MA) was interfaced to standard and custom laboratory equipment and programmed to perform rapid radiochemical analyses for quantitative PET studies. A Zymark XP robot arm was used to carry out the determination of unchanged (parent) radiotracer in plasma using only solid phase extraction methods. Robotic throughput for the assay of parent radiotracer in plasma is 4--6 samples/hour depending on the radiotracer. Robotic assays of parent compound in plasma were validated for the radiotracers [ 11 C]Benztropine, [ 11 C]cocaine, [ 11 C]clorgyline, [ 11 C]deprenyl, [ 11 C]methadone, [ 11 C]methylphenidate, [ 11 C]raclorpride, and [ 11 C]SR46349B. A simple robot-assisted methods development strategy has been implemented to facilitate the automation of plasma assays of new radiotracers

Application of the radiochemical - and the direct gamma ray spectrometry method to the burnup determination of irradiated uranium oxide

International Nuclear Information System (INIS)

Cunha, I.I.L.

1979-01-01

The burn up of natural U 3 O 8 that occurs by the action of thermal neutrons was determined, using the radioisotopes 144 Ce, 137 Cs, 103 Ru, 106 Ru and 95 Zr as monitors. The determination of the burn up was made using both destructive and non-destructive methods. In the non-destructive method, the technique of direct gamma-ray spectrometry was used and the radioisotopes mentioned were simultaneously counted in a Ge-Li detector. In the radiochemical method the same radioisotopes were isolated one from the other and from all other fission products before counting. The solvent extraction technique was used for the radiochemical separation of uranium, cerium, cesium and ruthenium. To separate zirconium and niobium, adsorption in silica-gel was used. The extraction agent employed to isolate cesium was dipycrilamine and for the separation of the other radioisotopes Di-(2-Ethyl Hexyl) Phosphoric acid (HDEHP) was used. (Author) [pt

Rapid and accurate determination of radiochemical purity of sup(99m)Tc compounds

International Nuclear Information System (INIS)

Tamat, S.R.

1977-01-01

The wide spread use of sup(99m)Tc-labelled radiopharmaceuticals and limitation of the short half-life of the isotope, is associated with an urgent need for a rapid, simple but accurate method for determining the radiochemical purity of the compound. A short paper chromatographic (KK) or thin layer chromatographic (KLT) method using 95% methanol or 0.9% saline solution as solvents, has solved the problem. With these methods, the amount of free sup(99m)Tc pertechnetate in a compound, can be determined in only a few minutes. These methods compare satisfactorily with lengtheir procedures. (author)

Modifiers of notch transcriptional activity identified by genome-wide RNAi

Directory of Open Access Journals (Sweden)

Firnhaber Christopher B

2010-10-01

Full Text Available Abstract Background The Notch signaling pathway regulates a diverse array of developmental processes, and aberrant Notch signaling can lead to diseases, including cancer. To obtain a more comprehensive understanding of the genetic network that integrates into Notch signaling, we performed a genome-wide RNAi screen in Drosophila cell culture to identify genes that modify Notch-dependent transcription. Results Employing complementary data analyses, we found 399 putative modifiers: 189 promoting and 210 antagonizing Notch activated transcription. These modifiers included several known Notch interactors, validating the robustness of the assay. Many novel modifiers were also identified, covering a range of cellular localizations from the extracellular matrix to the nucleus, as well as a large number of proteins with unknown function. Chromatin-modifying proteins represent a major class of genes identified, including histone deacetylase and demethylase complex components and other chromatin modifying, remodeling and replacement factors. A protein-protein interaction map of the Notch-dependent transcription modifiers revealed that a large number of the identified proteins interact physically with these core chromatin components. Conclusions The genome-wide RNAi screen identified many genes that can modulate Notch transcriptional output. A protein interaction map of the identified genes highlighted a network of chromatin-modifying enzymes and remodelers that regulate Notch transcription. Our results open new avenues to explore the mechanisms of Notch signal regulation and the integration of this pathway into diverse cellular processes.

Intein-modified enzymes, their production and industrial applications

Science.gov (United States)

Apgar, James; Lessard, Philip; Raab, Michael R.; Shen, Binzhang; Lazar, Gabor; de la Vega, Humberto

2016-10-11

A method of predicting an intein insertion site in a protein that will lead to a switching phenotype is provided. The method includes identifying a plurality of C/T/S sites within the protein; selecting from the plurality of C/T/S/ sites those that are ranked 0.75 or higher by a support vector machine, within ten angstroms of the active site of the protein, and at or near a loop-.beta.-sheet junction or a loop-.alpha.-helix junction. A method of controlling protein activity and hosts including proteins with controlled activity are also provided. Also, intein modified proteins and plants containing intein modified proteins are provided.

Ethylene glycol assisted preparation of Ti(4+)-modified polydopamine coated magnetic particles with rough surface for capture of phosphorylated proteins.

Science.gov (United States)

Ma, Xiangdong; Ding, Chun; Yao, Xin; Jia, Li

2016-07-27

The reversible protein phosphorylation is very important in regulating almost all aspects of cell life, while the enrichment of phosphorylated proteins still remains a technical challenge. In this work, polydopamine (PDA) modified magnetic particles with rough surface (rPDA@Fe3O4) were synthesized by introduction of ethylene glycol in aqueous solution. The PDA coating possessing a wealth of catechol hydroxyl groups could serve as an active medium to immobilize titanium ions through the metal-catechol chelation, which makes the fabrication of titanium ions modified rPDA@Fe3O4 particles (Ti(4+)-rPDA@Fe3O4) simple and very convenient. The spherical Ti(4+)-rPDA@Fe3O4 particles have a surface area of 37.7 m(2) g(-1) and superparamagnetism with a saturation magnetization value of 38.4 emu g(-1). The amount of Ti element in the particle was measured to be 3.93%. And the particles demonstrated good water dispersibility. The particles were used as adsorbents for capture of phosphorylated proteins and they demonstrated affinity and specificity for phosphorylated proteins due to the specific binding sites (Ti(4+)). Factors affecting the adsorption of phosphorylated proteins on Ti(4+)-rPDA@Fe3O4 particles were investigated. The adsorption capacity of Ti(4+)-rPDA@Fe3O4 particles for κ-casein was 1105.6 mg g(-1). Furthermore, the particles were successfully applied to isolate phosphorylated proteins in milk samples, which demonstrated that Ti(4+)-rPDA@Fe3O4 particles had potential application in selective separation of phosphorylated proteins. Copyright © 2016 Elsevier B.V. All rights reserved.

Immobilization of ferrocene-modified SNAP-fusion proteins

NARCIS (Netherlands)

Wasserberg, D.; Uhlenheuer, D.; Neirynck, P.; Neirynck, Pauline; Cabanas Danés, Jordi; Schenkel, J.H.; Ravoo, B.J.; An, Q.; Huskens, Jurriaan; Milroy, L.G.; Brunsveld, Luc; Jonkheijm, Pascal

2013-01-01

The supramolecular assembly of proteins on surfaces has been investigated via the site-selective incorporation of a supramolecular moiety on proteins. To this end, fluorescent proteins have been site-selectively labeled with ferrocenes, as supramolecular guest moieties, via SNAP-tag technology. The

Design of the Laboratory-Scale Plutonium Oxide Processing Unit in the Radiochemical Processing Laboratory

Energy Technology Data Exchange (ETDEWEB)

Lumetta, Gregg J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Meier, David E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tingey, Joel M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Amanda J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Delegard, Calvin H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Edwards, Matthew K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Orton, Robert D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rapko, Brian M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smart, John E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-05-01

This report describes a design for a laboratory-scale capability to produce plutonium oxide (PuO₂) for use in identifying and validating nuclear forensics signatures associated with plutonium production, as well as for use as exercise and reference materials. This capability will be located in the Radiochemical Processing Laboratory at the Pacific Northwest National Laboratory. The key unit operations are described, including PuO₂ dissolution, purification of the Pu by ion exchange, precipitation, and re-conversion to PuO₂ by calcination.

A radiochemical procedure for the determination of Po-210 in environmental samples

International Nuclear Information System (INIS)

Godoy, J.M.; Schuettelkopf, H.

1980-07-01

A radiochemical procedure for the determination of Po-210 in environmental samples was developed. Soil, sediments, filter materials, plants, water and food samples can be analyzed for Po-210. Wet ashing is achieved with HNO 3 + H 2 O 2 or HCl + HNO 3 . To separate disturbing substances, a coprecipitation with Te is used for sample materials containing silica. Po-210 deposition from HCl solution on Ag platelets with other sample materials is possible directly. Deposited Po-210 is counted by α-spectrometry. For chemical yield determination Po-208 is added, yields range between 60% and 100%. A lower detection limit of about 0,002 pCi Po-210/sample is achievable. (orig./HP) [de

An OGA-Resistant Probe Allows Specific Visualization and Accurate Identification of O-GlcNAc-Modified Proteins in Cells.

Science.gov (United States)

Li, Jing; Wang, Jiajia; Wen, Liuqing; Zhu, He; Li, Shanshan; Huang, Kenneth; Jiang, Kuan; Li, Xu; Ma, Cheng; Qu, Jingyao; Parameswaran, Aishwarya; Song, Jing; Zhao, Wei; Wang, Peng George

2016-11-18

O-linked β-N-acetyl-glucosamine (O-GlcNAc) is an essential and ubiquitous post-translational modification present in nucleic and cytoplasmic proteins of multicellular eukaryotes. The metabolic chemical probes such as GlcNAc or GalNAc analogues bearing ketone or azide handles, in conjunction with bioorthogonal reactions, provide a powerful approach for detecting and identifying this modification. However, these chemical probes either enter multiple glycosylation pathways or have low labeling efficiency. Therefore, selective and potent probes are needed to assess this modification. We report here the development of a novel probe, 1,3,6-tri-O-acetyl-2-azidoacetamido-2,4-dideoxy-d-glucopyranose (Ac 3 4dGlcNAz), that can be processed by the GalNAc salvage pathway and transferred by O-GlcNAc transferase (OGT) to O-GlcNAc proteins. Due to the absence of a hydroxyl group at C4, this probe is less incorporated into α/β 4-GlcNAc or GalNAc containing glycoconjugates. Furthermore, the O-4dGlcNAz modification was resistant to the hydrolysis of O-GlcNAcase (OGA), which greatly enhanced the efficiency of incorporation for O-GlcNAcylation. Combined with a click reaction, Ac 3 4dGlcNAz allowed the selective visualization of O-GlcNAc in cells and accurate identification of O-GlcNAc-modified proteins with LC-MS/MS. This probe represents a more potent and selective tool in tracking, capturing, and identifying O-GlcNAc-modified proteins in cells and cell lysates.

radiochemical study on the medically and technology radionuclides of some lanthanides

International Nuclear Information System (INIS)

Aglan, H.A.E.

2010-01-01

In this work, trials for the production of the medically and technologically interesting 139 Ce and 142 Pr radionuclides through cyclotron irradiations using protons and alpha particles were studied. The radiochemical separation of no-carrier-added cerium from proton irradiated lanthanum was studied by solvent extraction using DEE, TBP and TPPO, the latter reagent being employed for the first time for separation of radio cerium from bulk of lanthanum. Distribution coefficients of cerium and lanthanum were investigated as a function of equilibrium time and HNO 3 concentration. A mixture of 0.05 M K 2 Cr 2 O 7 and 0.1 M H 2 SO 4 was used as an oxidizing agent to improve the separation efficiency of cerium. A comparative study of the three extractants released that DEE is the best for separation of cerium from bulk of lanthanum oxide. The target was prepared by pressing. The production of 139 Ce of high radionuclidic and chemical purity via irradiation of lanthanum oxide target at MGC-20 cyclotron with protons of energy 14.5 is described. The experimental yield was found to be 153 kBq/μAh .The adsorption behaviour of La/Ce system on Dowex 50W-X8 in different media, namely, nitric acid, acetate buffer and citrate buffer was studied as a function of the concentration of nitric acid and buffer ph. In addition, in cation-exchange column chromatography experiments, three different eluants, namely, citrate buffer of ph 5.5, 0.1 M EDTA and 0.2 M α-HIBA, were employed for separation of Ce (III) from La (III). The optimum conditions for improvement of radiochemical separation of no-carrier-added 139 Ce from proton irradiated lanthanum were applied using the most suitable chelating agent 0.2 M α-HIBA. The purification of 139 Ce from macro amount of La (III) was done using two columns in a sequence. The experimental yield was found to be 200 kBq/μAh.

The reliability of radiochemical and chemical trace analyses in environmental materials

International Nuclear Information System (INIS)

Heinonen, Jorma.

1977-12-01

After theoretically exploring the factors which influence the quality of analytical data as well as the means by which a sufficient quality can be assured and controlled, schemes of different kinds have been developed and applied in order to demonstrate the analytical quality assurance and control in practice. Methods have been developed for the determination of cesium, bromine and arsenic by neutron activation analysis at the natural ''background'' concentration level in environmental materials. The calibration of methods is described. The methods were also applied on practical routine analysis, the results of which are briefly reviewed. In the case of Ce the precision of a comprehensive calibration was found to vary between 5.2-9.2% as a relative standard deviation, which agrees well with the calculated statistical random error 5.7-8.7%. In the case of Br the method showed a reasonable precision, about 11% on the average, and accuracy. In employing the method to analyze died samples containing Br from 3 to 12 ppm a continuous control of precison was performed. The analysis of As demonstrates the many problems and difficulties associated with environmental analysis. In developing the final method four former intercomparison materials of IAEA were utilized in the calibration. The tests performed revealed a systematic error. In this case a scheme was developed for the continuous control of both precision and accuracy. The results of radiochemical analyses in environmental materials show a reliability somewhat better than that occuring in the determination of stable trace elements. According to a rough classification, 15% of the results of radiochemical analysis show excellent reliability, whereas 60% show a reliability adequate for certain purposes. The remaining 15% are excellent, 60% adequate for some purposes and 30% good-for-nothing. The reasons for often insufficient reliability of results are both organizational and technical. With reasonable effort and

Remote sampling of process fluids in radiochemical plants

International Nuclear Information System (INIS)

Sengar, P.B.; Bhattacharya, R.; Ozarde, P. D.; Rana, D.S.

1990-01-01

Sampling of process fluids, continuous or periodic, is an essential requirement in any chemical process plant, so as to keep a control on process variables. In a radiochemical plant the task of taking and conveying the samples is a very tricky affair. This is due to the fact that neither the vessels/equipment containing radioactive effluents can be approached for manual sampling nor sampled fluids can be handled directly. The problems become more accute with higher levels of radioactivity. As such, inovative systems have to be devised to obtain and handle the raioactive samples employing remote operations. The remote sampling system developed in this Division has some of the unique features such as taking only requisite amount of samples in microlitre range, practically maintenance free design, avoidence of excess radioactive fluids coming out of process systems, etc. The paper describes in detail the design of remote sampling system and compares the same with existing systems. The design efforts are towards simplicity in operation, obtaining homogenised representative samples and highly economical on man-rem expenditure. The performance of a prototype system has also been evaluated. (author). 3 refs

Physical Activity Modifies the Association between Dietary Protein and Lean Mass of Postmenopausal Women.

Science.gov (United States)

Martinez, Jessica A; Wertheim, Betsy C; Thomson, Cynthia A; Bea, Jennifer W; Wallace, Robert; Allison, Matthew; Snetselaar, Linda; Chen, Zhao; Nassir, Rami; Thompson, Patricia A

2017-02-01

Maintenance of lean muscle mass and related strength is associated with lower risk for numerous chronic diseases of aging in women. Our aim was to evaluate whether the association between dietary protein and lean mass differs by physical activity level, amino acid composition, and body mass index categories. We performed a cross-sectional analysis of a prospective cohort. Participants were postmenopausal women from the Women's Health Initiative with body composition measurements by dual-energy x-ray absorptiometry (n=8,298). Our study measured percent lean mass, percent fat mass, and lean body mass index. Linear regression models adjusted for scanner serial number, age, calibrated energy intake, race/ethnicity, neighborhood socioeconomic status, and recreational physical activity were used to determine the relationship between protein intake and body composition measures. Likelihood ratio tests and stratified analysis were used to investigate physical activity and body mass index as potential effect modifiers. Biomarker-calibrated protein intake was positively associated with percent lean mass; women in the highest protein quintile had 6.3 percentage points higher lean mass than the lowest quintile (Plean body mass index were both inversely related to protein intake (both Plean body mass index (P interaction =0.011). Leucine intake was associated with lean mass, as were branched chain amino acids combined (both Plean mass in postmenopausal women. Importantly, those that also engage in physical activity have the highest lean mass across body mass index categories. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

A rapid, simple method for obtaining radiochemically pure hepatic heme

International Nuclear Information System (INIS)

Bonkowski, H.L.; Bement, W.J.; Erny, R.

1978-01-01

Radioactively-labelled heme has usually been isolated from liver to which unlabelled carrier has been added by long, laborious techniques involving organic solvent extraction followed by crystallization. A simpler, rapid method is devised for obtaining radiochemically-pure heme synthesized in vivo in rat liver from delta-amino[4- 14 C]levulinate. This method, in which the heme is extracted into ethyl acetate/glacial acetic acid and in which porphyrins are removed from the heme-containing organic phase with HCl washes, does not require addition of carrier heme. The new method gives better heme recoveries than and heme specific activities identical to, those obtained using the crystallization method. In this new method heme must be synthesized from delta-amino[4- 14 C]levulinate; it is not satisfactory to use [2- 14 C]glycine substrate because non-heme counts are isolated in the heme fraction. (Auth.)

Radiochemical investigations on the solubility of molybdatophosphate in phosphate determination

International Nuclear Information System (INIS)

Noack, S.

1975-01-01

The solubility of various molybdatophosphates was determined under the conditions of a gravimetric phosphate determination by radiochemical means by labelling PO 4 3- with P-32. Starting with various conditions for phosphate determination via the molybdatophosphate of quinoline, 8-hydroxyquinoline, dimorpholino ethane, N,N,N',N'-tetrakis-β-hydroxypropyl ethylene diamine and N,N,N',N'-tetrakis-β-hydroxybutyl ethylene diamine, a general working rule was developed to determine the solubility. Taking the example of quinoline molybdatophosphates, a series of influencing factors - work, concentration and measuring parameters - were investigated in order to be able to limit the reliability region of the gravimetric phosphate determination. Depending on the conditions, the measured solubilities were between 10 -10 and 10 -6 Mol/l, the corresponding degrees of precipitation between 99.0 and 99.9999%. Apparent solubility products were calculated for the different molybdatophosphates using computer programmes especially developed for this purpose. (orig./RB) [de

Hanford Environmental Restoration data validation process for chemical and radiochemical analyses

International Nuclear Information System (INIS)

Adams, M.R.; Bechtold, R.A.; Clark, D.E.; Angelos, K.M.; Winter, S.M.

1993-10-01

Detailed procedures for validation of chemical and radiochemical data are used to assure consistent application of validation principles and support a uniform database of quality environmental data. During application of these procedures, it was determined that laboratory data packages were frequently missing certain types of documentation causing subsequent delays in meeting critical milestones in the completion of validation activities. A quality improvement team was assembled to address the problems caused by missing documentation and streamline the entire process. The result was the development of a separate data package verification procedure and revisions to the data validation procedures. This has resulted in a system whereby deficient data packages are immediately identified and corrected prior to validation and revised validation procedures which more closely match the common analytical reporting practices of laboratory service vendors

An ontology-based search engine for protein-protein interactions.

Science.gov (United States)

Park, Byungkyu; Han, Kyungsook

2010-01-18

Keyword matching or ID matching is the most common searching method in a large database of protein-protein interactions. They are purely syntactic methods, and retrieve the records in the database that contain a keyword or ID specified in a query. Such syntactic search methods often retrieve too few search results or no results despite many potential matches present in the database. We have developed a new method for representing protein-protein interactions and the Gene Ontology (GO) using modified Gödel numbers. This representation is hidden from users but enables a search engine using the representation to efficiently search protein-protein interactions in a biologically meaningful way. Given a query protein with optional search conditions expressed in one or more GO terms, the search engine finds all the interaction partners of the query protein by unique prime factorization of the modified Gödel numbers representing the query protein and the search conditions. Representing the biological relations of proteins and their GO annotations by modified Gödel numbers makes a search engine efficiently find all protein-protein interactions by prime factorization of the numbers. Keyword matching or ID matching search methods often miss the interactions involving a protein that has no explicit annotations matching the search condition, but our search engine retrieves such interactions as well if they satisfy the search condition with a more specific term in the ontology.

Expression of PAT and NPT II proteins during the developmental stages of a genetically modified pepper developed in Korea.

Science.gov (United States)

Kim, Hyo Jin; Lee, Si Myung; Kim, Jae Kwang; Ryu, Tae Hun; Suh, Seok Cheol; Cho, Hyun Suk

2010-10-27

Estimation of the protein levels introduced in a biotechnology-derived product is conducted as part of an overall safety assessment. An enzyme-linked immunosorbent assay (ELISA) was used to analyze phosphinothricin acetyltransferase (PAT) and neomycin phosphotransferase II (NPT II) protein expression in a genetically modified (GM) pepper plant developed in Korea. PAT and NPT II expression levels, based on both dry weight and fresh weight, were variable among different plant generations and plant sections from isolated genetically modified organism (GMO) fields at four developmental stages. PAT expression was highest in leaves at anthesis (11.44 μg/gdw and 2.17 μg/gfw) and lowest in roots (0.12 μg/gdw and 0.01 μg/gfw). NPT II expression was also highest in leaves at anthesis (17.31 μg/gdw and 3.41 μg/gfw) and lowest in red pepper (0.65 μg/gdw and 0.12 μg/gfw). In pollen, PAT expression was 0.59-0.62 μg/gdw, while NPT II was not detected. Both PAT and NPT II showed a general pattern of decreased expression with progression of the growing season. As expected, PAT and NPT II protein expression was not detectable in control pepper plants.

Characterization of filter cartridges from the IEA-R1 reactor by radiochemical method

International Nuclear Information System (INIS)

Geraldo, Bianca; Vicente, Roberto; Ferreira, Robson J.; Goes, Marcos M.; Marumo, Julio T.

2015-01-01

The filter cartridges used in water purification system of research nuclear reactor IEA-R1 are considered radioactive wastes after their useful life. The characterization of these wastes is one of the stages of management, which aims to identify and quantify the radionuclides present, including those known as 'difficult to measure' (DTM) radionuclides. Establish a radiochemical analysis methodology for this type of waste is a difficult job, not only by the application of these techniques, but also by the amount of radionuclides that should be analyzed. In the waste produced in a nuclear reactor, the most important radionuclides are fission products, activation products and transuranic elements. Since these radionuclides emit gamma radiation not measurable in its decay process and consequently are difficult to measure, their concentrations can be estimated by indirect methods such as scale factors. This method is used to evaluate the DTM concentration, which is represented by alpha and beta nuclides using the correlation between them and the radionuclide key, a gamma emitter. The objective of this work is to describe a radiochemical analysis methodology for gamma emitter nuclides, present in the filter cartridges, evaluating the activity and concentrations by destructive assays. At the same time, two studies have been performed by non-destructive assays, the first one based on dose rates and the point kernel method to correlate the results and the second one based on calibration efficiency with Monte Carlo method. These studies belong to the radioactive waste characterization program that has been conducted at the Waste Management Laboratory of Nuclear and Energy Research Institute, IPEN-CNEN/SP. (author)

Characterization of filter cartridges from the IEA-R1 reactor by radiochemical method

Energy Technology Data Exchange (ETDEWEB)

Geraldo, Bianca; Vicente, Roberto; Ferreira, Robson J.; Goes, Marcos M.; Marumo, Julio T., E-mail: bgeraldo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

The filter cartridges used in water purification system of research nuclear reactor IEA-R1 are considered radioactive wastes after their useful life. The characterization of these wastes is one of the stages of management, which aims to identify and quantify the radionuclides present, including those known as 'difficult to measure' (DTM) radionuclides. Establish a radiochemical analysis methodology for this type of waste is a difficult job, not only by the application of these techniques, but also by the amount of radionuclides that should be analyzed. In the waste produced in a nuclear reactor, the most important radionuclides are fission products, activation products and transuranic elements. Since these radionuclides emit gamma radiation not measurable in its decay process and consequently are difficult to measure, their concentrations can be estimated by indirect methods such as scale factors. This method is used to evaluate the DTM concentration, which is represented by alpha and beta nuclides using the correlation between them and the radionuclide key, a gamma emitter. The objective of this work is to describe a radiochemical analysis methodology for gamma emitter nuclides, present in the filter cartridges, evaluating the activity and concentrations by destructive assays. At the same time, two studies have been performed by non-destructive assays, the first one based on dose rates and the point kernel method to correlate the results and the second one based on calibration efficiency with Monte Carlo method. These studies belong to the radioactive waste characterization program that has been conducted at the Waste Management Laboratory of Nuclear and Energy Research Institute, IPEN-CNEN/SP. (author)

Texturized dairy proteins.

Science.gov (United States)

Onwulata, Charles I; Phillips, John G; Tunick, Michael H; Qi, Phoebi X; Cooke, Peter H

2010-03-01

Dairy proteins are amenable to structural modifications induced by high temperature, shear, and moisture; in particular, whey proteins can change conformation to new unfolded states. The change in protein state is a basis for creating new foods. The dairy products, nonfat dried milk (NDM), whey protein concentrate (WPC), and whey protein isolate (WPI) were modified using a twin-screw extruder at melt temperatures of 50, 75, and 100 degrees C, and moistures ranging from 20 to 70 wt%. Viscoelasticity and solubility measurements showed that extrusion temperature was a more significant (P extruded dairy protein ranged from rigid (2500 N) to soft (2.7 N). Extruding at or above 75 degrees C resulted in increased peak force for WPC (138 to 2500 N) and WPI (2.7 to 147.1 N). NDM was marginally texturized; the presence of lactose interfered with its texturization. WPI products extruded at 50 degrees C were not texturized; their solubility values ranged from 71.8% to 92.6%. A wide possibility exists for creating new foods with texturized dairy proteins due to the extensive range of states achievable. Dairy proteins can be used to boost the protein content in puffed snacks made from corn meal, but unmodified, they bind water and form doughy pastes with starch. To minimize the water binding property of dairy proteins, WPI, or WPC, or NDM were modified by extrusion processing. Extrusion temperature conditions were adjusted to 50, 75, or 100 degrees C, sufficient to change the structure of the dairy proteins, but not destroy them. Extrusion modified the structures of these dairy proteins for ease of use in starchy foods to boost nutrient levels. Dairy proteins can be used to boost the protein content in puffed snacks made from corn meal, but unmodified, they bind water and form doughy pastes with starch. To minimize the water binding property of dairy proteins, whey protein isolate, whey protein concentrate, or nonfat dried milk were modified by extrusion processing. Extrusion

Amperometric Immunosensor Based on a Protein A/Deposited Gold Nanocrystals Modified Electrode for Carbofuran Detection

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Xia Sun

2011-12-01

Full Text Available In this paper, an amperometric immunosensor modified with protein A/deposited gold nanocrystals (DpAu was developed for the ultrasensitive detection of carbofuran residues. First, DpAu were electrodeposited onto the Au electrode surface to absorb protein A (PA and improve the electrode conductivity. Then PA was dropped onto the surface of DpAu film, used for binding antibody Fc fragments. Next, anti-carbofuran monoclonal antibody was immobilized on the PA modified electrode. Finally, bovine serum albumin (BSA was employed to block the possible remaining active sites avoiding any nonspecific adsorption. The fabrication procedure of the immunosensor was characterized by electrochemical impedance spectroscopy (EIS and cyclic voltammetry (CV, respectively. With the excellent electroconductivity of DpAu and the PA’s oriented immobilization of antibodies, a highly efficient immuno-reaction and detection sensitivity could be achieved. The influences of the electrodeposition time of DpAu, pH of the detection solution and incubation time on the current response of the fabricated immunosensor were investigated. Under optimized conditions, the current response was proportional to the concentration of carbofuran which ranged from 1 to 100 ng/mL and 100 ng/mL to 100 μg/mL. The detection limit was 0.1924 ng/mL. The proposed carbofuran immnuosensor exhibited high specificity, reproducibility, stability and regeneration performance, which may open a new door for ultrasensitive detection of carbofuran residues in vegetables and fruits.

Preparation, radiochemical analysis and biodistribution of 99mTc-dihydrobis(1-pyrazolyl)borate

International Nuclear Information System (INIS)

Owunwanne, A.; Abdel-Dayem, H.; Yacoub, T.

1987-01-01

Optimum preparation of 99m Tc-dihydrobis(1-pyrazolyl)borate ( 99m Tc-HBPz 2 ) was done by mixing 1.4 mg/ml HBPz 2 and 1.0 mg/ml of stanous PYP. Radiochemical analysis of the preparation using paper chromatography (PC), thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) indicated a stable product with one major component. The labelling efficiency was approximately 90%. Animal biodistribution studies performed in mice showed that most of the injected radioactivity was confined to the liver, kidney, lungs, intestine and heart. The heart to blood ratio was small but persisted up to 3 hrs. after the injection. (orig.) [de

Senp1 Is Essential for Desumoylating Sumo1-Modified Proteins but Dispensable for Sumo2 and Sumo3 Deconjugation in the Mouse Embryo

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Prashant Sharma

2013-05-01

Full Text Available Posttranslational modification with small ubiquitin-like modifier (Sumo regulates numerous cellular and developmental processes. Sumoylation is dynamic with deconjugation by Sumo-specific proteases (Senps regulating steady-state levels. Different Senps are found in distinct subcellular domains, which may limit their deconjugation activity to colocalizing Sumo-modified proteins. In vitro, Senps can discriminate between the different Sumo paralogs: Sumo1 versus the highly related Sumo2 and Sumo3 (Sumo2/3, which can form poly-Sumo chains. However, a full understanding of Senp specificity in vivo is still lacking. Here, using biochemical and genetic approaches, we establish that Senp1 has an essential, nonredundant function to desumoylate Sumo1-modified proteins during mouse embryonic development. Senp1 specificity for Sumo1 conjugates represents an intrinsic function and not simply a product of colocalization. In contrast, Senp1 has only a limited role in Sumo2/3 desumoylation, although it may regulate Sumo1-mediated termination of poly-Sumo2/3 chains.

Radiochemical and thermal studies of the cation-exchanged forms of synthetic zeolite Linde sieve A

Energy Technology Data Exchange (ETDEWEB)

Banerjee, S P [Saugar Univ. (India). Dept. of Chemistry

1976-02-01

The compositions of the cobalt and silver-exchanged forms of synthetic zeolite Sieve A have been determined by radiochemical and TGA studies and correspond to Co/sub 6/A.19.8H/sub 2/O and Ag/sub 12/..cap alpha... 20H/sub 2/O respectively (A=Al/sub 12/Si/sub 12/O/sub 48//sup 12/-). Heating of these zeolites inhibits their capacity for cation exchange and water absorption. No evidence of occluded NaAlO/sub 2/ has been found.

Physicochemical and Antioxidant Properties of Buckwheat Protein Isolates with Different Polyphenolic Content Modified by Limited Hydrolysis with Trypsin

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Xiao-Yan Wang

2012-01-01

Full Text Available Effects of limited hydrolysis with trypsin on the physicochemical and antioxidant properties of buckwheat protein isolates (BPIs obtained with untreated and 2-propanol-extracted meal have been investigated and compared. The dephenolization treatment significantly improved the hydrolysis of BPI, which resulted in the gradual decrease in total and protein-bound polyphenolic content, but an increase in the free polyphenolic content. The hydrolysis of globulins was much easier than that of the albumins. The removal of polyphenols improved the hydrolysis of the albumin fraction. The modified BPIs with high polyphenolic content exhibited much higher DPPH radical scavenging activity and reducing power, but poorer ferrous ion chelating ability than those with low polyphenolic content. These results suggest that the limited hydrolysis is suitable for modification of the properties of buckwheat proteins.

Development of a radiochemical sensor. Part I: Feasibility study

Energy Technology Data Exchange (ETDEWEB)

Tarancon, A. [Departament de Quimica Analitica, Facultat de Quimica, Universitat de Barcelona, C/ Marti Franques 1, 08028 Barcelona (Spain); Garcia, J.F. [Departament de Pintura, Facultat de Belles Arts, Universitat de Barcelona, C/ Pau Gargallo 4, 08028 Barcelona (Spain)]. E-mail: jfgarcia@apolo.qui.ub.es; Rauret, G. [Departament de Quimica Analitica, Facultat de Quimica, Universitat de Barcelona, C/ Marti Franques 1, 08028 Barcelona (Spain)

2005-05-04

The evolution of nuclear activities and criteria for radiation protection have led to a continuous increase in measures to monitor and control the environment and therefore in the number of determinations required for such purposes. Classical analytical procedures are time-consuming, labor-intense and generate a large amount of waste. The alternative use of sensors for such determinations has seen very limited development. The present study focuses on the evaluation of the behavior of a prototype radiochemical sensor for liquid effluents. The sensor is based on a receptor made of a plastic scintillator and is capable of continuous, on-time and accurate remote quantification of the activity of alpha, beta and beta-gamma emitters. Low-level active solutions of {sup 90}Sr/{sup 90}Y, {sup 238}Pu, {sup 134}Cs and {sup 60}Co in matrices of groundwater, seawater and drinking water were quantified with prediction errors lower than 10% in most cases. The study also yields information about light generation and transmission and transductor configuration that will be useful in the design of future versions of this sensor.

A general approach to the construction of 'very accurate' or 'definitive' methods by radiochemical NAA and the role of these methods in QA

International Nuclear Information System (INIS)

Dybczynski, R.

1998-01-01

Constant progress in instrumentation and methodology of inorganic trace analysis is not always paralleled by improvement in reliability of analytical results. Our approach to construction of 'very accurate' methods for the determination of selected trace elements in biological materials by RNAA is based on an assumption that: (i) The radionuclide in question should be selectively and quantitatively isolated from the irradiated sample by a suitable radiochemical scheme, optimized with respect to this particular radionuclide, yielding finally the analyte in the state of high radiochemical purity what assures interference-free measurement by gamma-ray spectrometry. (ii) The radiochemical scheme should be based on ion exchange and/or extraction column chromatography resulting in an easy automatic repetition of an elementary act of distribution of the analyte and accompanying radionuclides between stationary and mobile phases. (iii) The method should have some intrinsic mechanisms incorporated into the procedure preventing any possibility of making gross errors. Based on these general assumptions, several more specific rules for devising of 'very accurate' methods were formulated and applied when elaborating our methods for the determination of copper, cobalt, nickel, cadmium, molybdenum and uranium in biological materials. The significance of such methods for Quality Assurance is pointed out and illustrated by their use in the certification campaign of the new Polish biological CRMs based on tobacco

Radiochemical study on preparation and quality control of 1-125/1-131 labelled some organic compounds for medical uses

International Nuclear Information System (INIS)

El-azoney, K.M.S.E.

1997-01-01

The main objective of this thesis is to investigate the optimum condition for the radioiodination of some organic compounds which find wide applications in nuclear medicine. Iodine-131 (T 1 /2= 8.04 d) which is of great importance in the field, are used for this purpose. long chain fatty acids such as 16-Bromo-hexadecanoic (16-brHDA) and -phenyl -fatty acids such as 15-p-iodophenyl pentadecanoic acid (p-IPPA) will be used as model substrates. 1- Labelling of 16-Br-HDA with Na 131 I. Labelling of 16-BrHDA will be investigated via the non-isotopic exchange between 16-Br HDA and Na 131 I to give 16- 131 IHDA. In order to obtain a high radiochemical yield with high radiochemical purity for the product 16- 131 IHDA, simple and fast methods will be followed. The influence of reagents concentrations, time, temperature, solvents and four quaternary ammonium salts as phase transfer catalysts with only one crown ether will be studied. The determination of reaction velocities and activation energies of catalysed systems was effected and compared with results on the dry state system. 2- Labelling of p-Ipa with Na 131 I. Radioiodination of 15-p-iodophenyl pentadecanoic acid is investigated by the nucleophilic substitution reaction via the isotopic exchange between p-Ipa and Na 131 I. As with 16-BrHDA, factors affecting the labelling yield such as reagent concentrations, solvents, reaction time, temperature and catalyst, is examine. The effect of different temperatures on the radiochemical yield of P- 131 Ipa is studied to determine the activation energy of the exchange reaction. Because of the necessity to separate the iodinated products from the starting materials, high performance liquid chromatographic techniques were applied for this purpose. 3.15 figs., 3.2 tabs., 179 refs

Mitochondrial associated ubiquitin fold modifier-1 mediated protein conjugation in Leishmania donovani.

Directory of Open Access Journals (Sweden)

Sreenivas Gannavaram

2011-01-01

Full Text Available In this report, we demonstrate the existence of the ubiquitin fold modifier-1 (Ufm1 and its conjugation pathway in trypanosomatid parasite Leishmania donovani. LdUfm1 is activated by E1-like enzyme LdUba5. LdUfc1 (E2 specifically interacted with LdUfm1 and LdUba5 to conjugate LdUfm1 to proteinaceous targets. Mass spectrometry analysis revealed that LdUfm1 is conjugated to Leishmania protein targets that are associated with mitochondria. Immunofluorescence experiments showed that Leishmania Ufm1, Uba5 and Ufc1 are associated with the mitochondria. The demonstration that all the components of this system as well as the substrates are associated with mitochondrion suggests it may have physiological roles not yet described in any other organism. Overexpression of a non-conjugatable form of LdUfm1 and an active site mutant of LdUba5 resulted in reduced survival of Leishmania in the macrophage. Since mitochondrial activities are developmentally regulated in the life cycle of trypanosomatids, Ufm1 mediated modifications of mitochondrial proteins may be important in such regulation. Thus, Ufm1 conjugation pathway in Leishmania could be explored as a potential drug target in the control of Leishmaniasis.

Assessment of radiochemical purity of [18F]fludeoxyglucose by high pressure liquid chromatography (HPLC)

International Nuclear Information System (INIS)

Lacerda, Aline E.; Silva, Juliana B.; Silveira, Marina B.; Ferreira, Soraya Z.

2011-01-01

The quality control of [ 18 F]fludeoxyglucose ( 18 FDG) has received attention due to its increasing clinical use. Although the quality requirements of 18 FDG are established in various pharmacopoeia, the suitability of all testing methods used should be verified under actual conditions of use and documented. The aim of this study was to develop a high pressure liquid chromatography (HPLC) method for radiochemical purity evaluation of 18 FDG, based on pharmacopoeia references, and to verify its suitability for routine quality control in our centre. HPLC analysis was performed with an Agilent HPLC. 18 FDG and impurities were separated on an anion-exchange column by isocratic elution with 0.1 M NaOH as the mobile phase. Detection was accomplished with refractive index and NaI (Tl) scintillation detectors. The flow rate of the mobile phase was set at 0.8 mL/min and the column temperature was kept at 35 deg C. Specificity, linearity, precision and robustness were assessed to verify if the method was adequate for its intended purpose. Retention time of 18 FDG was not affected by the presence of other components of the formulation and a good peak resolution was achieved. The analytical curve of 18 FDG was linear, with a correlation coefficient value of 0.9995. Intraday repeatable precision, reported as the relative standard deviation, was 0.11%. Analytical procedure remained unaffected by small variations in mobile phase flow rate. Results evidenced that HPLC is suitable for radiochemical purity evaluation of 18 FDG, considering operational conditions of our laboratory. (author)

A genetically modified protein-based hydrogel for 3D culture of AD293 cells.

Directory of Open Access Journals (Sweden)

Xiao Du

Full Text Available Hydrogels have strong application prospects for drug delivery, tissue engineering and cell therapy because of their excellent biocompatibility and abundant availability as scaffolds for drugs and cells. In this study, we created hybrid hydrogels based on a genetically modified tax interactive protein-1 (TIP1 by introducing two or four cysteine residues in the primary structure of TIP1. The introduced cysteine residues were crosslinked with a four-armed poly (ethylene glycol having their arm ends capped with maleimide residues (4-armed-PEG-Mal to form hydrogels. In one form of the genetically modification, we incorporated a peptide sequence 'GRGDSP' to introduce bioactivity to the protein, and the resultant hydrogel could provide an excellent environment for a three dimensional cell culture of AD293 cells. The AD293 cells continued to divide and displayed a polyhedron or spindle-shape during the 3-day culture period. Besides, AD293 cells could be easily separated from the cell-gel constructs for future large-scale culture after being cultured for 3 days and treating hydrogel with trypsinase. This work significantly expands the toolbox of recombinant proteins for hydrogel formation, and we believe that our hydrogel will be of considerable interest to those working in cell therapy and controlled drug delivery.

Optimization, validation and standardization of a method of measuring the radiochemical purity of 99mTc-HMDP in Necker hospital

International Nuclear Information System (INIS)

Dumont, A.; Izembart, M.; Barritault, L.

1997-01-01

By the end of 1996, the tests of the radiochemical purity (RCP) of preparation of HMDP- 99m Tc at Necker hospital were effected by means of 'Tech-Kit' technique which allowed making evident only one radiochemical impurity, the free TcO 4 - . So, the aim of this work has been the search for another technique able to detect also the reduced hydrolyzed 99m Tc, and then, to optimize, validate and standardize this new technique. Several methods have been tested and compared on different points (the chemical species identified, practical difficulties, duration, reproducibility) in order to chose 'the best' one, consisting in associating two TLC (migration time, 3 minutes): - TLC no.1, ITLC-SG/Methyl-ethyl-ketone; - TLC no.2, ITLC-SG/1M Sodium acetate. This method has been subsequently: - optimized, concerning the quantity of deposed sampling, way of deposit drying, migration range, reading protocol by radio-chromatograph; - validated, by verifying the migration of radiochemical impurities by means of controls and by evaluating its sensitivity; - standardized, by defining the interest zones for interpreting the radio-chromatograms, by evaluating the reproducibility and by calculating the 'normal values' of RCP percentages. This method has been adopted as routine and with current recoil (40 preparations) and our conditions of realizations, the extreme values of the percentages obtained for the impurity zones of interests, have been the following: - TcO 4 - zone, [0.39%-1.07%]; - hydrolyzed reduced Tc zone, [0.96%-5.09%]. By taking into account their distribution we calculated a minimum RCP value of 94% to accept the preparation (the RCP being defined as equal to 100% - % TcO 4 - % hydrolyzed reduced Tc)

Trace element evaluation of different varieties of chewing gum by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Zaidi, J.H.; Arif, M.; Fatima, I.; Ahmad, S.; Qureshi, I.H.

2000-01-01

Extensive use of chewing gums, by children in particular, entails the evaluation of trace element contents in them. Radiochemical neutron activation analysis (RNAA) was successfully employed to determine the concentration of 35 trace elements (essential, toxic and nonessential) in eight different brands of chewing gum generally consumed in Rawalpindi/Islamabad area. Comparison of trace element data of our work with literature has been presented. None of the elements detected in the brands of chewing gum examined was found to be present at a level representing a substantial contribution to the total dietary intake of the element. (author)

Radiochemical method for evaluating the effect of antibiotics on Escherichia coli biofilms

International Nuclear Information System (INIS)

Dix, B.A.; Cohen, P.S.; Laux, D.C.; Cleeland, R.

1988-01-01

A simple radiochemical method for evaluating the action of antibiotics on Escherichia coli cells in biofilms is reported. After growth, biofilms of E. coli ATCC 25922 on disks of urinary catheter material were suspended in fresh medium containing or lacking an antibiotic, incubated for 4 h at 37 degrees C, and pulse-labeled with [ 3 H]leucine for 5 min. Radioactivity in trichloracetic acid-precipitable material in the biofilm and in the surrounding medium (planktonic E. coli) was then measured. Antibiotic-induced inhibition of incorporation of [ 3 H]leucine into the cells in the biofilm was far less pronounced than incorporation into planktonic cells and, furthermore, correlated well with loss in viable counts. The method is simple, inexpensive, and extremely timesaving

Application of radiochemical methods to investigate mercury in water-ecosystems

International Nuclear Information System (INIS)

Kraemer, H.J.

1975-01-01

Two topics have been picked out of the vast scope of possible questions on mercury ecology in this work: 1) Development for a method of enrichment of mercury from surface water and neutron activation analytical determination of the influence of dissolved Hg compounds on the water/fish part-process taking course in the water-ecosystem with the help of radiochemical tracer methods. The developed enrichment method, adsorbents on aniline sulphur resin basis, was applied to the activation analytical Hg determination in model solutions with a specified content as well as in water of the Rhine, where a Hg content of 1.1 +- 0.2 x 10 -3 ppm was determined. 2) The uptake (and yield) of Hg (NO 3 ) 2 and CH 3 HgCl from fish was traced using radioactive tracers Hg 197 and Hg 203. The measured accumulation and yield kinetics and observed influence due to additions enable the development of model to interpret the interaction between fish and dissolved Hg compounds. (RB) [de

SCAN- a maintenance-free flowrate meter with direct digital read-out for computerised control applications in radiochemical plants

Energy Technology Data Exchange (ETDEWEB)

Shah, B V; Siddiqui, I A; Theyyunni, T K [Process Engineering and Systems Division, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

In radiochemical plants, the choice of flowrate sensor is subject to stringent requirements of fail-safe design and freedom from maintenance. The SCAN remote digital direct indicating flowrate meter described in this paper was developed to meet the requirements of flowrate and transmitting it to the control room, and to a computerised control system. SCAN is designed on the principle that flowrate through an orifice is a function of the head of liquid acting upon it. SCAN consists of a small chamber which receives the flow, and discharges it through an orifice located in bottom. The level of liquid in the pot represents the flowrate of the input stream. SCAN has been developed into an accurate, rugged and practical device by refinements in the design of internals, and by introducing a special end-section which makes the calibration insensitive to location. An important feature of SCAN is that it is passive, maintenance free, fail-safe device and contains no moving parts. There is no liquid hold up in the SCAN when idle, which is a desirable feature for the radiochemical plant environment. (author). 3 figs., 2 tabs.

Radiochemical studies, pre-clinical investigation and preliminary clinical evaluation of "1"7"0Tm-EDTMP prepared using in-house freeze-dried EDTMP kit

International Nuclear Information System (INIS)

Das, Tapas; Shinto, Ajit; Kamaleshwaran, Koramadai K.; Sarma, Haladhar D.; Mohammed, Sahiralam Khan; Mitra, Arpit; Lad, Sangita; Rajan, M.G.R.; Banerjee, Sharmila

2017-01-01

The objective of the present work is to formulate "1"7"0Tm-EDTMP using an in-house freeze-dried EDTMP kit and evaluate its potential as a bone pain palliation agent. Patient dose of "1"7"0Tm-EDTMP was prepared with high radiochemical purity using the lyophilized kit at room temperature within 15 min. Pre-clinical evaluation in normal Wistar rats revealed selective skeletal accumulation with extended retention. Preliminary clinical investigation in 8 patients with disseminated skeletal metastases exhibited selective uptake in the bone and retention therein for a long duration. - Highlights: • Formulation of patient dose of "1"7"0Tm-EDTMP using freeze-dried EDTMP kit. • Radiochemical studies and pre-clinical evaluation of the agent in animal model. • Clinical evaluation in eight cancer patients with disseminated skeletal metastases.

Radiochemical purity and in vitro stability of Tc-99m radiopharmaceuticals

International Nuclear Information System (INIS)

Vucina, J.

2001-01-01

The increased contents of long lived 99 Tc, oxygen and cupric ions could affect the labeling yield of eight radiopharmaceuticals. Oxygen and in leaser extend copper were found to affect the radiochemical purity of the preparations. In vitro stability of radiopharmaceuticals, examined on 99m Tc(Sn)-pyrosphoshate solutions, was extended when ascorbic acid was added as the chemical stabilizer. The quantity of 5x10 -7 mol/dm 3 of ascorbic acid was found to be sufficient to keep the content of 99m Tc-pertechnetate below 1 % six hours after labeling even in the cases when 99m Tc was present in high radioactive concentrations (740-814 GBq/dm 3 ). The results led to the development of the kits in which ascorbic or gentisic acid are the standards component in the kit composition (author)

Immunotoxicological Evaluation of Genetically Modified Rice Expressing Cry1Ab/Ac Protein (TT51-1) by a 6-Month Feeding Study on Cynomolgus Monkeys

OpenAIRE

Tan, Xiaoyan; Zhou, Xiaobing; Tang, Yao; Lv, Jianjun; Zhang, Lin; Sun, Li; Yang, Yanwei; Miao, Yufa; Jiang, Hua; Chen, Gaofeng; Huang, Zhiying; Wang, Xue

2016-01-01

The present study was performed to evaluate the food safety of TT51-1, a new type of genetically modified rice that expresses the Cry1Ab/Ac protein (Bt toxin) and is highly resistant to most lepidopteran pests. Sixteen male and 16 female cynomolgus monkeys were randomly divided into four groups: conventional rice (non-genetically modified rice, non-GM rice), positive control, 17.5% genetically modified rice (GM rice) and 70% GM rice. Monkeys in the non-GM rice, positive control, and GM rice g...

Burn-up determination of irradiated uranium oxide by means of direct gama spectrometry and by radiochemical method

International Nuclear Information System (INIS)

Cunha, I.I.L.; Nastasi, M.J.C.; Lima, F.W.

1981-09-01

The burn-up of thermal neutrons irradiated U 3 O 8 (natural uranium) samples has been determined by using both direct gamma spectrometry and radiochemical methods and the results obtained were compared. The fission products 144 Ce, 103 Ru, 106 Ru, 137 Cs and 95 Zr were chosen as burn-up monitors. In order to isolate the radioisotopes chosen as monitors, a radiochemical separation procedure has been established, in which the solvent extraction technique was used to separate cerium, cesium and ruthenium one from the other and all of them from uranium. The separation between zirconium and niobium and of both elements from the other radioisotopes and uranium was accomplished by means of adsorption on a silica-gel column, followed by selective elution of zirconium and of niobium. When use was made of the direct gamma-ray spectrometry method, the radioactivity of each nuclide of interest was measured in presence of all others. For this purpose use was made of gamma-ray spectrometry and of a Ge-Li detector. Comparison of burn-up values obtained by both methods was made by means of Student's 't' test, and this showed that results obtained in each case are statistically equal. (Author) [pt

Conceptual Design for the Pilot-Scale Plutonium Oxide Processing Unit in the Radiochemical Processing Laboratory

Energy Technology Data Exchange (ETDEWEB)

Lumetta, Gregg J.; Meier, David E.; Tingey, Joel M.; Casella, Amanda J.; Delegard, Calvin H.; Edwards, Matthew K.; Jones, Susan A.; Rapko, Brian M.

2014-08-05

This report describes a conceptual design for a pilot-scale capability to produce plutonium oxide for use as exercise and reference materials, and for use in identifying and validating nuclear forensics signatures associated with plutonium production. This capability is referred to as the Pilot-scale Plutonium oxide Processing Unit (P3U), and it will be located in the Radiochemical Processing Laboratory at the Pacific Northwest National Laboratory. The key unit operations are described, including plutonium dioxide (PuO2) dissolution, purification of the Pu by ion exchange, precipitation, and conversion to oxide by calcination.

A modified strategy for sequence specific assignment of protein NMR spectra based on amino acid type selective experiments

International Nuclear Information System (INIS)

Schubert, Mario; Labudde, Dirk; Leitner, Dietmar; Oschkinat, Hartmut; Schmieder, Peter

2005-01-01

The determination of the three-dimensional structure of a protein or the study of protein-ligand interactions requires the assignment of all relevant nuclei as an initial step. This is nowadays almost exclusively performed using triple-resonance experiments. The conventional strategy utilizes one or more pairs of three dimensional spectra to obtain redundant information and thus reliable assignments. Here, a modified strategy for obtaining sequence specific assignments based on two dimensional amino acid type selective triple-resonance experiments is proposed. These experiments can be recorded with good resolution in a relatively short time. They provide very specific and redundant information, in particular on sequential connectivities, that drastically increases the ease and reliability of the assignment procedure, done either manually or in an automated fashion. The new strategy is demonstrated with the protein domain PB1 from yeast CDC24p

Waste treatment at the Radiochemical Engineering Development Center

International Nuclear Information System (INIS)

Brunson, R.R.; Bond, W.D.; Chattin, F.R.; Collins, R.T.; Sullivan, G.R.; Wiles, R.H.

1997-01-01

At the Radiochemical Engineering Development Center (REDC) irradiated targets are processed for the recovery of valuable radioisotopes, principally transuranium nuclides. A system was recently installed for treating the various liquid alkaline waste streams for removal of excess radioactive contaminants at the REDC. Radionuclides that are removed will be stored as solids and thus the future discharge of radionuclides to liquid low level waste tank storage will be greatly reduced. The treatment system is of modular design and is installed in a hot cell (Cubicle 7) in Building 7920 at the REDC where preliminary testing is in progress. The module incorporates the following: (1) a resorcinol-formaldehyde resin column for Cs removal, (2) a cross flow filtration unit for removal of rare earths and actinides as hydroxide, and (3) a waste solidification unit. Process flowsheets for operation of the module, key features of the module design, and its computer-assisted control system are presented. Good operability of the cross flow filter system is mandatory to the successful treatment of REDC wastes. Results of tests to date on the operation of the filter in its slurry collection mode and its slurry washing mode are presented. These tests include the effects of entrained organic solvent in the waste stream feed to the filter

Development of a radiochemical neutron activation analysis procedure for determination of rhenium in biological and environmental samples at ultratrace level

Czech Academy of Sciences Publication Activity Database

Kučera, Jan; Byrne, A. R.; Mizera, Jiří; Lučaníková, M.; Řanda, Zdeněk

2006-01-01

Roč. 269, č. 2 (2006), s. 251-257 ISSN 0236-5731 R&D Projects: GA ČR(CZ) GA203/04/0943 Institutional research plan: CEZ:AV0Z10480505 Keywords : radiochemical neutron activation analysis * rhenium * biological and environmental samples Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.509, year: 2006

Remote-controlled module-assisted synthesis of O-(2-[18F]fluoroethyl)-L-tyrosine as tumor PET tracer using two different radiochemical routes

International Nuclear Information System (INIS)

Wang Mingwei; Yin Duanzhi; Zhang Lan; Zhou Wei; Wang Yongxian

2006-01-01

The positron-emitter fluorine-18 labeled amino acid O-(2-[ 18 F]fluoroethyl)-L-tyrosine ([ 18 F]FET) has shown very promising perspectives for brain tumor diagnosis with positron emission tomography (PET). There have been two existing preparation routes of [ 18 F]FET named direct nucleophilic radiofiuorination of protected L-tyrosine and radiofiuoroallcylation of unprotected L-tyrosine, respectively. A general module was designed specifically for the routine synthesis of [ 18 F]FET, which could be suitable for the present two chemical methods with simple modifications. The fluorinated intermediates and the final product were separated and purified using solid phase extraction (SPE) on the Sep-Pak silica plus cartridge instead of the time-consuming high performance liquid chromatography (HPLC) procedures. The total synthesis time was about 50-60 rain with good radiochemical yield (about 20-40%, no-decay-corrected) and good radiochemical purity (more than 97%) for both the synthetic methods. (authors)

The determination of the radiochemical purity of 99Tcm-DTPA-HSA injection

International Nuclear Information System (INIS)

Yin Guangrong; Zhang Yan

1996-01-01

A simple, rapid analytical method of radiochemical purity for the 99 Tc m -DTPA-HSA injection is established. 99 Tc m (VII), 99 Tc m (IV) and labelled compound 99 Tc m -DTPA-HSA are separated by two systems of paper chromatography on Whatman No.1. The solvent of the system A is 85% methanol and that of the system B is water-95% alcohol-ammonium hydroxide (volume ratio is 5:2:1). 90 Tc m (IV) and labelled compound are located at the origin, while R f of 99 Tc m (VII) is about 0.4-0.5 in the system A. R f of 99 Tc m (VII) and labelled compound are about 0.7-0.8, while 99 Tc m (IV) is located at the origin in the system B

On the presence of fictitious solar neutrino flux variations in radiochemical experiments

International Nuclear Information System (INIS)

Vladimirskii, B.M.; Bruns, A.V.

2004-01-01

The currently available data on solar neutrino flux variation in radiochemical experiments and Cherenkov measurements have so far defied a simple interpretation. Some of the results concerning these variations are indicative of their relationship to processes on the solar surface. It may well be that a poorly understood, uncontrollable factor correlating with solar activity indices affects the neutrino flux measurements. This factor is assumed to modulate the detection efficiency on different detectors in different ways. To test this assumption, we have analyzed all available radiochemical measurements obtained with the Brookhaven (1970-1994, 108 runs), GALLEX (1991-1997, 65 runs), and SAGE (1989-2000, 80 runs) detectors for possible instability of the detection efficiency. We consider the heliophysical situation at the final stage of the run, the last 7-27 days, when the products of the neutrino reaction with the target material had already been accumulated. All of the main results obtained previously by other authors were found to be reproduced for chlorine-argon measurements. The neutrino flux anticorrelates with the sunspot numbers only for an odd solar cycle. A similar behavior is observed for the critical frequencies of the E-ionosphere. The neutrino flux probably correlates with the A p magnetic activity index only for an even solar cycle. The predominance of a certain sign of the radial interplanetary magnetic field (IMF) in the last 14 (or 7) days of the run has the strongest effect on the recorded neutrino flux. The effect changes sign when the polarity of the general solar magnetic field is reversed and is most pronounced for the shortest runs (less than 50 days). The dependence of the flux on IMF polarity completely disappears if the corresponding index is taken for the first rather than the last days of the run. The IMF effect on the recorded neutrino flux was also found for short runs in the gallium-germanium experiment, but this effect for a given

How proteins modify water dynamics

Science.gov (United States)

Persson, Filip; Söderhjelm, Pär; Halle, Bertil

2018-06-01

Much of biology happens at the protein-water interface, so all dynamical processes in this region are of fundamental importance. Local structural fluctuations in the hydration layer can be probed by 17O magnetic relaxation dispersion (MRD), which, at high frequencies, measures the integral of a biaxial rotational time correlation function (TCF)—the integral rotational correlation time. Numerous 17O MRD studies have demonstrated that this correlation time, when averaged over the first hydration shell, is longer than in bulk water by a factor 3-5. This rotational perturbation factor (RPF) has been corroborated by molecular dynamics simulations, which can also reveal the underlying molecular mechanisms. Here, we address several outstanding problems in this area by analyzing an extensive set of molecular dynamics data, including four globular proteins and three water models. The vexed issue of polarity versus topography as the primary determinant of hydration water dynamics is resolved by establishing a protein-invariant exponential dependence of the RPF on a simple confinement index. We conclude that the previously observed correlation of the RPF with surface polarity is a secondary effect of the correlation between polarity and confinement. Water rotation interpolates between a perturbed but bulk-like collective mechanism at low confinement and an exchange-mediated orientational randomization (EMOR) mechanism at high confinement. The EMOR process, which accounts for about half of the RPF, was not recognized in previous simulation studies, where only the early part of the TCF was examined. Based on the analysis of the experimentally relevant TCF over its full time course, we compare simulated and measured RPFs, finding a 30% discrepancy attributable to force field imperfections. We also compute the full 17O MRD profile, including the low-frequency dispersion produced by buried water molecules. Computing a local RPF for each hydration shell, we find that the

Functional properties of unmodified and modified Jack bean ...

African Journals Online (AJOL)

The native Jack bean (Canavalia eniformis) starch was chemically modified through oxidation and acetylation. Proximate composition analysis revealed higher moisture, protein, fat and ash contents 'native unmodified than modified starches and higher yield in modified starches. Swelling capacity and solubility of all the ...

[Genetically modified food and allergies - an update].

Science.gov (United States)

Niemann, Birgit; Pöting, Annette; Braeuning, Albert; Lampen, Alfonso

2016-07-01

Approval by the European Commission is mandatory for placing genetically modified plants as food or feed on the market in member states of the European Union (EU). The approval is preceded by a safety assessment based on the guidance of the European Food Safety Authority EFSA. The assessment of allergenicity of genetically modified plants and their newly expressed proteins is an integral part of this assessment process. Guidance documents for the assessment of allergenicity are currently under revision. For this purpose, an expert workshop was conducted in Brussels on June 17, 2015. There, methodological improvements for the assessment of coeliac disease-causing properties of proteins, as well as the use of complex models for in vitro digestion of proteins were discussed. Using such techniques a refinement of the current, proven system of allergenicity assessment of genetically modified plants can be achieved.

The analysis of thallium in geological materials by radiochemical neutron activation and x-ray fluorescence spectrometry: a comparison

Energy Technology Data Exchange (ETDEWEB)

McGoldrick, P J; Robinson, P [Tasmania Univ., Sandy Bay, TAS (Australia)

1994-12-31

Carrier-based radiochemical neutron activation (RNAA) is a precise and accurate technique for the analysis of Tl in geological materials. For about a decade, until the mid-80s, a procedure modified from Keays et al. (1974) was used at the University of Melbourne to analyse for Tl in a wide variety of geological materials. Samples of powdered rock weighing several hundred milligrams each were irradiated in HIFAR for between 12 hours and 1 week, and subsequently fused with a sodium hydroxide - sodium peroxide mixture and several milligrams of inactive Tl carrier. Following acid digestion of the fusion mixture anion exchange resin was used to separate Tl from the major radioactive rock constituents. The Tl was then stripped from the resin and purified as thallium iodide and a yield measured gravimetrically. Activity from {sup 204}Tl (a {beta}-emitter with a 3 8 year half-life) was measured and Tl determined by reference to pure chemical standards irradiated and processed along with the unkowns. Detection limits for the longer irradiations were about one part per billion. Precision was monitored by repeat analyses of `internal standard` rocks and was estimated to be about five to ten percent (one standard deviation). On the other hand, X-ray fluorescence spectrometry (XRF) was seen as an excellent cost-effective alternative for thallium analysis in geological samples, down to 1 ppm. 6 refs. 1 tab., 1 fig.

The analysis of thallium in geological materials by radiochemical neutron activation and x-ray fluorescence spectrometry: a comparison

Energy Technology Data Exchange (ETDEWEB)

McGoldrick, P.J.; Robinson, P. [Tasmania Univ., Sandy Bay, TAS (Australia)

1993-12-31

Carrier-based radiochemical neutron activation (RNAA) is a precise and accurate technique for the analysis of Tl in geological materials. For about a decade, until the mid-80s, a procedure modified from Keays et al. (1974) was used at the University of Melbourne to analyse for Tl in a wide variety of geological materials. Samples of powdered rock weighing several hundred milligrams each were irradiated in HIFAR for between 12 hours and 1 week, and subsequently fused with a sodium hydroxide - sodium peroxide mixture and several milligrams of inactive Tl carrier. Following acid digestion of the fusion mixture anion exchange resin was used to separate Tl from the major radioactive rock constituents. The Tl was then stripped from the resin and purified as thallium iodide and a yield measured gravimetrically. Activity from {sup 204}Tl (a {beta}-emitter with a 3 8 year half-life) was measured and Tl determined by reference to pure chemical standards irradiated and processed along with the unkowns. Detection limits for the longer irradiations were about one part per billion. Precision was monitored by repeat analyses of `internal standard` rocks and was estimated to be about five to ten percent (one standard deviation). On the other hand, X-ray fluorescence spectrometry (XRF) was seen as an excellent cost-effective alternative for thallium analysis in geological samples, down to 1 ppm. 6 refs. 1 tab., 1 fig.

Utility of reversed phase high performance liquid chromatography for on-line yield determination of radiochemical separations: Studies with cobalt

International Nuclear Information System (INIS)

Subramanian, S.; Woittiez, J.R.W.

1993-01-01

This article indicates the potentials of high performance liquid chromatography (HPLC) as a radiochemical technique for multielement separation of neutron irradiated samples. The focus lies on the convenience to use the detector signal of the eluted components to indicate the chemical yield of the analyte, which has often proved to be a crucial step in radiochemical separations. Two signals have been utilized. The UV signal of the metal-ligand complexes separated by reversed phase HPLC and the radioactive response as a result of sample irradiation of carrier-tracer addition. Change in ratio is discussed between the two signals, if any, for a specific sample. Losses of metal as much as 65% were simulated and corrected using the individual UV response. The method promises improved accuracy for elemental analysis despite losses suffered during the various chemical steps. The procedure omits the necessity of additional analytical steps for yield determination. The present article aims at the chromatographic part of the study. Cobalt as cobalt diethyldithiocarbamate has been used to demonstrate the viability of the concept. The separation was developed on c C18 reverse phase analytical column and optimized on a semi preparative one

Pokemon siRNA Delivery Mediated by RGD-Modified HBV Core Protein Suppressed the Growth of Hepatocellular Carcinoma.

Science.gov (United States)

Kong, Jing; Liu, Xiaoping; Jia, Jianbo; Wu, Jinsheng; Wu, Ning; Chen, Jun; Fang, Fang

2015-10-01

Hepatocellular carcinoma (HCC) is a deadly human malignant tumor that is among the most common cancers in the world, especially in Asia. Hepatitis B virus (HBV) infection has been well established as a high risk factor for hepatic malignance. Studies have shown that Pokemon is a master oncogene for HCC growth, suggesting it as an ideal therapeutic target. However, efficient delivery system is still lacking for Pokemon targeting treatment. In this study, we used core proteins of HBV, which is modified with RGD peptides, to construct a biomimetic vector for the delivery of Pokemon siRNAs (namely, RGD-HBc-Pokemon siRNA). Quantitative PCR and Western blot assays revealed that RGD-HBc-Pokemon siRNA possessed the highest efficiency of Pokemon suppression in HCC cells. In vitro experiments further indicated that RGD-HBc-Pokemon-siRNA exerted a higher tumor suppressor activity on HCC cell lines, evidenced by reduced proliferation and attenuated invasiveness, than Pokemon-siRNA or RGD-HBc alone. Finally, animal studies demonstrated that RGD-HBc-Pokemon siRNA suppressed the growth of HCC xenografts in mice by a greater extent than Pokemon-siRNA or RGD-HBc alone. Based on the above results, Pokemon siRNA delivery mediated by RGD-modified HBV core protein was shown to be an effective strategy of HCC gene therapy.

Methods for nuclear material control used in the basic production of a typical radiochemical plant

International Nuclear Information System (INIS)

Kositsyn, V.F.; Mukhortov, N.F.; Korovin, Yu.I.; Rudenko, V.S.; Petrov, A.M.

1999-01-01

Techniques for destructive and non-destructive assay of the component and isotopic composition of nuclear materials are described, namely gravimetric, titrimetric, coulometric, mass spectrometry, as well as those based on registration of neutron and γ radiations. Their metrologic characteristics are described. The techniques described are suggested to be used for nuclear material (NM) control and accounting purposes at the model radiochemical plant for processing irradiated fuel subassemblies from power reactors. The measurement control program is also described. This program is intended for the measurement quality assurance in the framework of NM control and accountancy system [ru

Novel Highly Sensitive Protein Sensors Based on Tapered Optical Fibres Modified with Au-Based Nanocoatings

Directory of Open Access Journals (Sweden)

Aitor Urrutia

2016-01-01

Full Text Available Novel protein sensors based on tapered optical fibres modified with Au coatings deposited using two different procedures are proposed. Au-based coatings are deposited onto a nonadiabatic tapered optical fibre using (i a novel facile method composed of layer-by-layer deposition consisting of polycation (poly(allylamine hydrochloride, PAH and negatively charged SiO2 nanoparticles (NPs followed by the deposition of the charged Au NPs and (ii the sputtering technique. The Au NPs and Au thin film surfaces are then modified with biotin in order to bind streptavidin (SV molecules and detect them. The sensing principle is based on the sensitivity of the transmission spectrum of the device to changes in the refractive index of the coatings induced by the SV binding to the biotin. Both sensors showed high sensitivity to SV, with the lowest measured concentration levels below 2.5 nM. The calculated binding constant for the biotin-SV pair was 2.2×10-11 M−1 when a tapered fibre modified with the LbL method was used, with a limit of detection (LoD of 271 pM. The sensor formed using sputtering had a binding constant of 1.01×10-10 M−1 with a LoD of 806 pM. These new structures and their simple fabrication technique could be used to develop other biosensors.

Determination of radiochemical yields of 186Re-labelled complexes using thin layer chromatography

International Nuclear Information System (INIS)

Konirova, R.; Kohlickova, M.; Jedinakova-Krizova, V.

1999-01-01

The reaction conditions for synthesis of three rhenium complexes 186 Re-methylendiphosphonate (MDP), 186 Re-hydroxyethylidendiphosphonate (HEDP) and 186 Re-citrate have been investigated. Radiochemical yield of complexation has been determined by thin layer chromatography and paper chromatography. The rhenium complexation with corresponding ligand is dependent on pH values of reaction mixture, concentration of studied ligand (MDP, HEDP and sodium citrate) and concentration of reducing agent. Stannous chloride with ascorbic acid (as antioxidant) was used for reduction of perrhenate. The labeling yield of 186 Re-MDP was about 90 %, of 186 Re-HEDP more than 80 % and more than 75 % for 186 Re-citrate under optimum conditions. Besides, the possibility of application of porphyrins as organic ligands for complexation with rhenium isotopes is examined. (authors)

Radiochemical determination of Inertial Confinement Fusion capsule compression at the National Ignition Facility

Energy Technology Data Exchange (ETDEWEB)

Shaughnessy, D. A., E-mail: shaughnessy2@llnl.gov; Moody, K. J.; Gharibyan, N.; Grant, P. M.; Gostic, J. M.; Torretto, P. C.; Wooddy, P. T.; Bandong, B. B.; Cerjan, C. J.; Hagmann, C. A.; Caggiano, J. A.; Yeamans, C. B.; Bernstein, L. A.; Schneider, D. H. G.; Henry, E. A.; Fortner, R. J. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94551 (United States); Despotopulos, J. D. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94551 (United States); Radiochemistry Program, University of Nevada Las Vegas, Las Vegas, Nevada 89154 (United States)

2014-06-15

We describe a radiochemical measurement of the ratio of isotope concentrations produced in a gold hohlraum surrounding an Inertial Confinement Fusion capsule at the National Ignition Facility (NIF). We relate the ratio of the concentrations of (n,γ) and (n,2n) products in the gold hohlraum matrix to the down-scatter of neutrons in the compressed fuel and, consequently, to the fuel's areal density. The observed ratio of the concentrations of {sup 198m+g}Au and {sup 196g}Au is a performance signature of ablator areal density and the fuel assembly confinement time. We identify the measurement of nuclear cross sections of astrophysical importance as a potential application of the neutrons generated at the NIF.

Limits of the radiochemical and geochemical method for the test of nucleon stability

Energy Technology Data Exchange (ETDEWEB)

Bergamasco, L [CNR, Laboratorio di Cosmo-Geofisica, Turin, Italy; Texas A and M University, College Station, Tex.); Cini, G [CNR, Laboratorio di Cosmo-Geofisica; Torino, Universita, Turin, Italy)

1978-07-01

An estimate is obtained for the limiting nucleon lifetime that can be determined by the radiochemical method of Steinberg and Evans (1977), which counts the Ar-37 production from reactions due to nucleon decay in a large sample of KC2H3O2. To estimate the background rate, processes due to the atmospheric muon component are considered. It is found that the asymptotic limit on the maximum value of the nucleon lifetime is 2 x 10/sup 30/years. This value cannot be increased by going to larger depths or by using a larger sample, but is inherent in the method itself. To improve the limit one would have to resort to methods based on multiparticle decay modes.

Determination of trace elements in bottled water in Greece by instrumental and radiochemical neutron activation analyses

International Nuclear Information System (INIS)

Soupioni, M.J.; Symeopoulos, B.D.; Papaefthymiou, H.V.

2006-01-01

Four different bottled water brands sold in Greece in the winter of 2001-2002 were analyzed for a wide range of chemical elements, using neutron activation analysis (NAA). The elements Na and Br were determined instrumentally (INAA), whereas the other metals and trace elements radiochemically (RNAA). The results indicated that the mean level of all the elements determined in the samples were well within the European Union (EU) directive on drinking water and accomplish the drinking water standards of the World Health Organisation (WHO) as well as of the Food and Drug Administration (FDA). (author)

The effect of lunar soil, metal oxides on thermal and radio-chemical stability of amino acids

International Nuclear Information System (INIS)

Khenokh, M.A.; Lapinskaya, E.M.

1983-01-01

Data on study of the effect of lunar soil and some metal oxides characteristic both for land and sea basaltS of lunar sojls on thermal and radio-chemical stability of amino acids are presented. The data obtained permit to suppose that extremely small quantity of amino acids discovered in lunar soil is conditioned by their decomposition under combined effect of different types of radiation, solar wind and sharp change of temperature. Probably, the effect of soil on photochemical activity of UV-radiation of the Sun and solid-phase radiolysis is not practically observed

Planning for maintenance in radiochemical facilities [Paper No.: VB-2

International Nuclear Information System (INIS)

Balasubramanian, G.R.

1981-01-01

Reprocessing facilities in the earlier stages of development were planned mainly based on the concept of direct maintenance in view of the inherent advantage of man-machine interface and initial savings in the investment costs. With the mechanical processes finding a firm place in head-end operation and increase in down time necessary for elaborate decontamination efforts even for a minor modification has led to the review of the concept. For the same reason, the recent plants are based on the concept of harmonious blend of both direct and remote maintenance. The paper describes the planning needed from consideration of various aspects related to such concepts of maintenance during different phases of such type of facilities, highlighting some of the tools and special equipments to be developed for this purpose. A brief description of recent development in the field of remote maintenance is also given. Though the basic hot facility of reference is the one of reprocessing fast reactor fuels, the concepts and systems discussed are equally applicable to other radiochemical and radiometallurgical facilities also. (author)

Multiple organ histopathological changes in broiler chickens fed on genetically modified organism.

Science.gov (United States)

Cîrnatu, Daniela; Jompan, A; Sin, Anca Ileana; Zugravu, Cornelia Aurelia

2011-01-01

Diet can influence the structural characteristics of internal organs. An experiment involving 130 meat broilers was conducted during 42 days (life term for a meat broiler) to study the effect of feed with protein from genetically modified soy. The 1-day-old birds were randomly allocated to five study groups, fed with soy, sunflower, wheat, fish flour, PC starter. In the diet of each group, an amount of protein from soy was replaced with genetically modified soy (I - 0%, II - 25%, III - 50%, IV - 75%, V - 100% protein from genetically modified soy). The level of protein in soy, either modified, or non-modified, was the same. Organs and carcass weights were measured at about 42 days of age of the birds and histopathology exams were performed during May-June 2009. No statistically significant differences were observed in mortality, growth performance variables or carcass and organ yields between broilers consuming diets produced with genetically modified soybean fractions and those consuming diets produced with near-isoline control soybean fractions. Inflammatory and degenerative liver lesions, muscle hypertrophy, hemorrhagic necrosis of bursa, kidney focal tubular necrosis, necrosis and superficial ulceration of bowel and pancreatic dystrophies were found in tissues from broilers fed on protein from genetically modified soy. Different types of lesions found in our study might be due to other causes (parasites, viral) superimposed but their presence exclusively in groups fed with modified soy raises some serious questions about the consequences of use of this type of feed.

Metrological aspects of radiochemical methods for determining activity of gamma-emitting nuclides

International Nuclear Information System (INIS)

Shcherbakov, B.Y.

1986-01-01

The author considers the problem of metrological compatibility of the two stages in the radiochemical method of determining the activity of a gamma-emitting nuclide: chemical isolation of the nuclide and radiometric measurement of its activity. The authors show that preparation of the specimen in liquid form provides for important advantages compared with the traditional application of the solid residue onto a flat substate. The work here is of interest for analytical chemists who are involved with determination of the activity of gamma emitting nuclides such as Ru 103, Rh 106, Sn 113, Cs 134, Cs 137, La 140, Ce 141, Ce 144, Hg 203, Na 24, Mn 54, Fe 59, Co 60, Zn 65, Zr 95, and Nb 95, for example, in waste water or in emissions to the atmosphere, with the goal of protecting the environment

Continuous radiochemical analysis of fission products in a nuclear reactor water coolant

International Nuclear Information System (INIS)

Moskvin, L.N.; Zakharov, L.K.; Leont'ev, G.G.; Mel'nikov, V.A.; Orlenkov, I.S.; Slutskij, G.K.

1975-01-01

Method for continuous radiochemical analysis of I, Cs, Ba, Sr and Ce isotopes in a reactor water heat-transfer agent was developed. A continuous two-dimensional chromatographic process of complex mixtures separation of substances proved to be feasible on several parallel sorbent layers, which moved at constant velocities and separated by stationary intermediate collectors. Tests on model solutions containing I, Ce, Cs and Ba isotopes and on heat-carrier samples showed quantitative separation of elements. The results were indicative of a basic possibility of using multisorbent chromatographs for continuous control of multicomponent mixtures, particularly for control of radioactive fission product compositions in water heat-transfer agents in nuclear power plants. A diagram is shown for a two-dimensional chromatographic separation of a multicomponent mixture. Also shown is a flow chart of an installation for continuous control of iodine and cesium isotope activities

The study of radiochemical separation methods on gaseous Fission product krypton-88

International Nuclear Information System (INIS)

Yang Zhihong; Zhang Shengdong; Yang Lei; Ding Youqian; Sun Hongqing; Ma Peng

2012-01-01

Half-life of krypton-88 is 2.84 hours, high fission yields and a relatively large gamma branching ratio is had. The gas is short-lived fission products in burnup measurements. Only New fission products can extract from extraction in gas of fissile irradiation target. But krypton-88 with krypton-85, krypton-87, xenon -135, and xenon-138 is coexisted together, thus radiochemical separation must quickly taken. selected the irradiation time is 1-2 hours and cooling time is best 2 hours for sample preparation, krypton and xenon were separated using activated carbon adsorption, the ratio of krypton and xenon were measured by gamma spectroscopy. Then according to the ratio of krypton-85 and xenon-125 count rate coefficient around separation were calculated yield of krypton and decontamination factor of xenon and the final the yield of krypton-85 is calculated. (authors)

Radiochemical separation of cadmium-109

International Nuclear Information System (INIS)

Egamediev, S.; Mukhtarov, A.; Nurbaeva, D.; Rakhmanov, A.

2006-01-01

Full text: Cadmium-109 has a half-life of 461.9 days and decays by electron capture to 109 Ag with the emission of 88 keV γ-ray (3.79%) along with the characteristic X-ray from the K level of Ag, with energy of 22.5 keV. This radionuclide has found widespread use as a photon source in x-ray fluorescence analysis devices employed in industry for numerous applications such as the direct determination of gold in ores, the analysis of metals and identification of steels. Other applications range from its use as an electron source for measurement of densities of air-pollution samples, to tracer studies in mushrooms and mice and rats. In the nuclear medicine field there is growing interest in employing 109 Cd in a 109 Cd/ 109mA g generator, as an alternative to other biomedical generators of ultra short-lived gamma emitters. There are several methods for the production of 109 Cd in literature: 1. Bombardment of silver cyclotron target via 109 Ag(d,2n) 109 Cd reaction with 16 MeV deuterons. 2. Bombardment of natural silver target via 109 Ag(p,n) 109 Cd reaction with 14 MeV protons. 3. Proton bombardment of natural indium target with 96 MeV protons. 4. Irradiation of enriched 107 Ag target in high-flux nuclear reactor at neutron flux 2x10 15 n·cm -2 ·s -1 via 107 Ag(n,γ) 108 Ag → 108 Cd (n,γ) 109 Cd reaction. 5. Irradiation of enriched 108 Cd target in nuclear reactor at neutron flux 1x10 14 n·cm -2 ·s -1 via 108 Cd (n,γ) 109 Cd reaction. The production of 109 Cd with proton beam via 109 Ag(p,n) 109 Cd reaction is ideal for the cyclotron U-150, since it is not required the change of the regime for the machine functioning. Because of its relatively long half-life the time required for separation is also not an important factor, but its use as an X-ray source requires a very high radiochemical purity. In the present work we studied two methods for separation of 109 Cd from model solution of silver targets. First method is based on precipitation of silver as

Median Modified Wiener Filter for nonlinear adaptive spatial denoising of protein NMR multidimensional spectra

KAUST Repository

Cannistraci, Carlo Vittorio

2015-01-26

Denoising multidimensional NMR-spectra is a fundamental step in NMR protein structure determination. The state-of-the-art method uses wavelet-denoising, which may suffer when applied to non-stationary signals affected by Gaussian-white-noise mixed with strong impulsive artifacts, like those in multi-dimensional NMR-spectra. Regrettably, Wavelet\\'s performance depends on a combinatorial search of wavelet shapes and parameters; and multi-dimensional extension of wavelet-denoising is highly non-trivial, which hampers its application to multidimensional NMR-spectra. Here, we endorse a diverse philosophy of denoising NMR-spectra: less is more! We consider spatial filters that have only one parameter to tune: the window-size. We propose, for the first time, the 3D extension of the median-modified-Wiener-filter (MMWF), an adaptive variant of the median-filter, and also its novel variation named MMWF*. We test the proposed filters and the Wiener-filter, an adaptive variant of the mean-filter, on a benchmark set that contains 16 two-dimensional and three-dimensional NMR-spectra extracted from eight proteins. Our results demonstrate that the adaptive spatial filters significantly outperform their non-adaptive versions. The performance of the new MMWF* on 2D/3D-spectra is even better than wavelet-denoising. Noticeably, MMWF* produces stable high performance almost invariant for diverse window-size settings: this signifies a consistent advantage in the implementation of automatic pipelines for protein NMR-spectra analysis.

Median Modified Wiener Filter for nonlinear adaptive spatial denoising of protein NMR multidimensional spectra

KAUST Repository

Cannistraci, Carlo Vittorio; Abbas, Ahmed; Gao, Xin

2015-01-01

Denoising multidimensional NMR-spectra is a fundamental step in NMR protein structure determination. The state-of-the-art method uses wavelet-denoising, which may suffer when applied to non-stationary signals affected by Gaussian-white-noise mixed with strong impulsive artifacts, like those in multi-dimensional NMR-spectra. Regrettably, Wavelet's performance depends on a combinatorial search of wavelet shapes and parameters; and multi-dimensional extension of wavelet-denoising is highly non-trivial, which hampers its application to multidimensional NMR-spectra. Here, we endorse a diverse philosophy of denoising NMR-spectra: less is more! We consider spatial filters that have only one parameter to tune: the window-size. We propose, for the first time, the 3D extension of the median-modified-Wiener-filter (MMWF), an adaptive variant of the median-filter, and also its novel variation named MMWF*. We test the proposed filters and the Wiener-filter, an adaptive variant of the mean-filter, on a benchmark set that contains 16 two-dimensional and three-dimensional NMR-spectra extracted from eight proteins. Our results demonstrate that the adaptive spatial filters significantly outperform their non-adaptive versions. The performance of the new MMWF* on 2D/3D-spectra is even better than wavelet-denoising. Noticeably, MMWF* produces stable high performance almost invariant for diverse window-size settings: this signifies a consistent advantage in the implementation of automatic pipelines for protein NMR-spectra analysis.

Thermodynamics of protein folding using a modified Wako-Saitô-Muñoz-Eaton model.

Science.gov (United States)

Tsai, Min-Yeh; Yuan, Jian-Min; Teranishi, Yoshiaki; Lin, Sheng Hsien

2012-09-01

Herein, we propose a modified version of the Wako-Saitô-Muñoz-Eaton (WSME) model. The proposed model introduces an empirical temperature parameter for the hypothetical structural units (i.e., foldons) in proteins to include site-dependent thermodynamic behavior. The thermodynamics for both our proposed model and the original WSME model were investigated. For a system with beta-hairpin topology, a mathematical treatment (contact-pair treatment) to facilitate the calculation of its partition function was developed. The results show that the proposed model provides better insight into the site-dependent thermodynamic behavior of the system, compared with the original WSME model. From this site-dependent point of view, the relationship between probe-dependent experimental results and model's thermodynamic predictions can be explained. The model allows for suggesting a general principle to identify foldon behavior. We also find that the backbone hydrogen bonds may play a role of structural constraints in modulating the cooperative system. Thus, our study may contribute to the understanding of the fundamental principles for the thermodynamics of protein folding.

Elementary computation of radiation doses and shieldings for radiochemical laboratories; Calculo Elemental de dosis y blindajes para laboratorios radioquimicos

Energy Technology Data Exchange (ETDEWEB)

Jimeno de Osso, F

1971-07-01

Simple procedures for the calculation of radiation exposition, half thickness, shield thickness, etc. are described and equations and graphs are included for those gamma-emitting radionuclides, that are more often used in radiochemical laboratories. Application is made of these procedures to three radionuclides, bromine-82, sodium-24 and cobalt-60 which cover a rather wl.de energy range; theoretical results are compared with those obtained from experimental measurements. (Author) 23 refs.

Genetically modified anthrax lethal toxin safely delivers whole HIV protein antigens into the cytosol to induce T cell immunity

Science.gov (United States)

Lu, Yichen; Friedman, Rachel; Kushner, Nicholas; Doling, Amy; Thomas, Lawrence; Touzjian, Neal; Starnbach, Michael; Lieberman, Judy

2000-07-01

Bacillus anthrax lethal toxin can be engineered to deliver foreign proteins to the cytosol for antigen presentation to CD8 T cells. Vaccination with modified toxins carrying 8-9 amino acid peptide epitopes induces protective immunity in mice. To evaluate whether large protein antigens can be used with this system, recombinant constructs encoding several HIV antigens up to 500 amino acids were produced. These candidate HIV vaccines are safe in animals and induce CD8 T cells in mice. Constructs encoding gag p24 and nef stimulate gag-specific CD4 proliferation and a secondary cytotoxic T lymphocyte response in HIV-infected donor peripheral blood mononuclear cells in vitro. These results lay the foundation for future clinical vaccine studies.

Assessment of radiochemical purity of [{sup 18}F]fludeoxyglucose by high pressure liquid chromatography (HPLC)

Energy Technology Data Exchange (ETDEWEB)

Lacerda, Aline E.; Silva, Juliana B.; Silveira, Marina B.; Ferreira, Soraya Z., E-mail: radiofarmacoscdtn@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Unidade de Pesquisa e Producao de Radiofarmacos

2011-07-01

The quality control of [{sup 18}F]fludeoxyglucose ({sup 18}FDG) has received attention due to its increasing clinical use. Although the quality requirements of {sup 18}FDG are established in various pharmacopoeia, the suitability of all testing methods used should be verified under actual conditions of use and documented. The aim of this study was to develop a high pressure liquid chromatography (HPLC) method for radiochemical purity evaluation of {sup 18}FDG, based on pharmacopoeia references, and to verify its suitability for routine quality control in our centre. HPLC analysis was performed with an Agilent HPLC. {sup 18}FDG and impurities were separated on an anion-exchange column by isocratic elution with 0.1 M NaOH as the mobile phase. Detection was accomplished with refractive index and NaI (Tl) scintillation detectors. The flow rate of the mobile phase was set at 0.8 mL/min and the column temperature was kept at 35 deg C. Specificity, linearity, precision and robustness were assessed to verify if the method was adequate for its intended purpose. Retention time of {sup 18}FDG was not affected by the presence of other components of the formulation and a good peak resolution was achieved. The analytical curve of {sup 18}FDG was linear, with a correlation coefficient value of 0.9995. Intraday repeatable precision, reported as the relative standard deviation, was 0.11%. Analytical procedure remained unaffected by small variations in mobile phase flow rate. Results evidenced that HPLC is suitable for radiochemical purity evaluation of {sup 18}FDG, considering operational conditions of our laboratory. (author)

Radiochemical and chemical constituents in water from selected wells and springs from the southern boundary of the Idaho National Laboratory to the Hagerman Area, Idaho, 2003

Science.gov (United States)

Rattray, Gordon W.; Wehnke, Amy J.; Hall, L. Flint; Campbell, Linford J.

2005-01-01

The U.S. Geological Survey and the Idaho Department of Water Resources, in cooperation with the U.S. Department of Energy, sampled water from 14 sites as part of an ongoing study to monitor the water quality of the eastern Snake River Plain aquifer between the southern boundary of the Idaho National Laboratory (INL) and the Burley-Twin Falls-Hagerman area. The State of Idaho, Department of Environmental Quality, Division of INL Oversight and Radiation Control cosampled with the U.S. Geological Survey and the Idaho Department of Water Resources and their analytical results are included in this report. The samples were collected from four domestic wells, two dairy wells, two springs, four irrigation wells, one observation well, and one stock well and analyzed for selected radiochemical and chemical constituents. Two quality-assurance samples, sequential replicates, also were collected and analyzed. None of the concentrations of radiochemical or organic-chemical constituents exceeded the maximum contaminant levels for drinking water established by the U.S. Environmental Protection Agency. However, the concentration of one inorganic-chemical constituent, nitrate (as nitrogen), in water from site MV-43 was 20 milligrams per liter which exceeded the maximum contaminant level for that constituent. Of the radiochemical and chemical concentrations analyzed for in the replicate-sample pairs, 267 of the 270 pairs (with 95 percent confidence) were statistically equivalent.

Structural study of the AOT reverse micellar system. Influence of attractive interactions induced by the solubilisation of native and modified proteins

International Nuclear Information System (INIS)

Cassin, Guillaume

1994-01-01

This research thesis reports the study of the influence of intra-micellar attractions on the thermodynamic behaviour of reverse micellar systems, as well as of the effects induced by the solubilisation of natives or modified proteins. The author proposes a model to explain the decrease of attractions between droplets when the volume fraction occupied by reverse micelles increases. This model which highlights the importance of depletion forces between reverse micelles, allows the building up of a theoretical relationship between the bonding parameter and the volume fraction of reverse micelles. In order to understand the appearance of an attractive term related to the solubilisation of native cytochrome-c in these systems, this protein has been chemically modified. The author highlights the role of the charge born by a micellar probe on the thermodynamic behaviour of micro-emulsions. Then, the author applies the model of dimerizing adhesive spheres to reverse micellar systems containing native cytochrome-c. He shows that theoretical predictions of this model are in agreement with obtained experimental results [fr

Development of radiochemical separation method for determination of toxic elements in biological samples

International Nuclear Information System (INIS)

Maihara, V.A.; Vasconcellos, M.B.A.; Favaro, D.I.T.; Armelin, M.J.A.

1990-01-01

In order to determine Hg, Sb, As and Se in biological materials by neutron activation analysis, a radiochemical separation was developed. The chemical separation procedure used was based on the digestion of the irradiated sample in a mixture of H NO 3 and H 2 SO 4 in a teflon bomb, at 130 0 C for 1 to 4 hours. After the dissolution of organic matter, Hg and Sb were retained by a Dowex 2-X8 resin column in 6 M HCl. The effluent was passed through a TDO, tin dioxide column which retains As and Se in 3 M HCl medium. Radioactive tracers of these elements were used to determine the yields of the separation process. Certified reference materials were analyzed to check the precision and accuracy of the method. (author)

Development of a radiochemical separation method for toxic elements determination from biologic samples

International Nuclear Information System (INIS)

Malhara, V.A.; Vasconcellos, M.B.A.; Favaro, D.I.T.; Armelin, M.J.A.

1990-01-01

In order to determine Hg, Sb, As and Se in biological materials by neutron activation analysis, a radiochemical separation was developed. The chemical separation procedure used was based on the digestion of the irradiated sample in a mixture of HNO 3 and H 2 SO 4 in a teflon bomb, at 130 0 C for 1 to 4 hours. After the dissolution of organic matter, Hg and Sb were retained by a Dowex 2-XB resin column in 6M HCI. The efluent was passed through a TDO, tin dioxide column which retains As and Se in 3M HCI medium. Radioactive tracers of these elements were used to determine the yields of the separation process. Certified reference materials were analyzed to check the precision and accuracy of the method. (author)

Radiochemical search for neutron-rich isotopes of element 107

International Nuclear Information System (INIS)

Schaedel, M.

1987-01-01

Recent mass calculations have indicated that there is a region of deformed nuclei around neutron number N=162 that is especially stable against spontaneous fission. Barrier heights of about 5 MeV for Z = 107 nuclides can be extrapolated. To search for new, neutron-rich isotopes of element 107 in radiochemical experiments with 254 Es as a target an on-line chemical separation of element 107 (EKA-Rhenium), especially from the actinide elements is needed. An on-line gas-phase chemistry was developed with the homolog Re based on the volatility of the oxide which is transported in an O 2 containing atmosphere along a temperature gradient in a quartz tube and is condensed onto a thin Ta coated Ni-foil. The authors applied this technique in two series of experiments with their rotating wheel on-line gas-phase chemistry apparatus at the 88-inch cyclotron where they irradiated 254 Es as a target with 93 MeV and 96 MeV 16 O ions to search for 266 107. The assignment of the observed alpha events between 8 and 9 MeV to possibly (1) non actinide contaminants like 212 Po, (2) known isotopes of heavy elements like 261 105, or (3) a new isotope will be discussed

Radiochemical neutron activation analysis based multi-elemental analysis of high purity gallium

International Nuclear Information System (INIS)

Tashimova, F.A.; Sadikov, I.I; Salimov, M.I.; Zinov'ev, V.G.

2006-01-01

Full text: Gallium is one of the widely used materials in semiconductor and optoelectronics industry. Gallium is used to produce infrared detectors, piezoelectric sensors, high- and low-temperature transistors for space and defense technology. One of the most important requirements for semiconductor materials of gallium compounds is an excessive high purity for layers and films. Information on impurities (type of an impurity, concentration, character of distribution) is important as for better understanding of the physical and chemical processes taking place in formed semiconductor structures and for the 'know-how' of devices on their basis. The object of this work is to develop radiochemical neutron activation technique for analysis of high purity gallium. Irradiation of 0.1 g of gallium sample in neutron flux of 5·10 13 cm -2 s -1 for 5 hours will result in induced activity of more than 10 8 Bq, due to 72 Ga radionuclide, half-life of which is 14.1 hours. Therefore to perform instrumental NAA of gallium long period (10 day) cooling is required, and high sensitive determination of elements producing short- and long-lived radionuclides (T 1/2 72 Ga. We have studied the behavior of gallium in extraction-chromatographic system 'TBP-HCl'. The experiments have shown that higher factor of distribution (D) and capacity on gallium can be achieved when 'TBP-4M HCl' system is used. However more than 10 trace elements have high D and thus they cannot be separated from 72 Ga. To resolve the problem and increase the number of separated trace elements we have used preliminary satisfaction of chromatographic column with tellurium, which has D higher than the most of elements in 'TBP-4M HCl' system and thus suppresses extraction of elements. Distribution profile of gallium along the column and elution curve of 25 trace elements have been measured. Chemical yields of separated elements measured by using radiotracers are more than 93%. On the basis of the carried out researches

Cell-free system for synthesizing membrane proteins cell free method for synthesizing membrane proteins

Science.gov (United States)

Laible, Philip D; Hanson, Deborah K

2013-06-04

The invention provides an in vitro method for producing proteins, membrane proteins, membrane-associated proteins, and soluble proteins that interact with membrane-associated proteins for assembly into an oligomeric complex or that require association with a membrane for proper folding. The method comprises, supplying intracytoplasmic membranes from organisms; modifying protein composition of intracytoplasmic membranes from organism by modifying DNA to delete genes encoding functions of the organism not associated with the formation of the intracytoplasmic membranes; generating appropriate DNA or RNA templates that encode the target protein; and mixing the intracytoplasmic membranes with the template and a transcription/translation-competent cellular extract to cause simultaneous production of the membrane proteins and encapsulation of the membrane proteins within the intracytoplasmic membranes.

Mesoporous silica particles modified with graphitic carbon: interaction with human red blood cells and plasma proteins

Energy Technology Data Exchange (ETDEWEB)

Martinez, Diego Stefani Teodoro; Franqui, Lidiane Silva; Bettini, Jefferson; Strauss, Mathias, E-mail: diego.martinez@lnnano.cnpem.br [Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); Damasceno, Joao Paulo Vita; Mazali, Italo Odone [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

2016-07-01

Full text: In this work the interaction of the mesoporous silica particles (SBA-15, ∼700 nm) modified with graphitic carbon (SBA-15/C) on human red blood cells (hemolysis) and plasma proteins (protein corona formation) is studied. XPS and CHN analysis showed that the carbon content on the SBA-15/C samples varied from 2 to 10% and was tuned by the functionalization step. The formed carbon structures where associated to graphitic nanodomains coating the pores surface as verified by Raman spectroscopy and {sup 13}C NMR. Advanced TEM/EELS analysis showed that the carbon structures are distributed along the SBA-15 mesopores. SAXS and textural analyses were used to confirm that the porous structure of the silica support is kept after the modification procedure and to calculate the number of graphitic carbon stacked layers coating the mesopores. After incubation of SBA-15 with human red blood cells (RBCs), it was observed a dose-dependent hemolytic effect, probably, due to binding of the material silanol-rich surface to the phosphatidylcholine molecules from the RBC membrane. The graphitic carbon modifications have mitigated this effect, indicating that the graphitic carbon coating protected the silanol groups of the particle surface hindering the hemolysis. Considering the protein corona formation, selective biomolecular interaction of proteins was observed for the different materials using gel electrophoresis (SDS-PAGE) analysis. Besides, graphitic carbon modification decreased the amount of proteins on the corona. Together, the in vitro hemolysis and protein corona assays are promising biological models to understand the influence of silica surface functionalization on their bionano-interactions. Finally, our work contributes to the development of fundamental research on such nanomaterials chemistry in the emerging field of nanobioscience and nanotoxicology. (author)

Chemically modified carbon nanotubes as material enhanced laser desorption ionisation (MELDI) material in protein profiling

International Nuclear Information System (INIS)

Najam-ul-Haq, M.; Rainer, M.; Schwarzenauer, T.; Huck, C.W.; Bonn, G.K.

2006-01-01

Biomarkers play a potential role in the early detection and diagnosis of a disease. Our aim is to derivatize carbon nanotubes for exploration of the differences in human body fluids e.g. serum, through matrix assisted laser desorption ionisation/time of flight mass spectrometry (MALDI/TOF-MS) that can be related to disease and subsequently to be employed in the biomarker discovery process. This application we termed as the material enhanced laser desorption ionisation (MELDI). The versatility of this technology is meant to increase the amount of information from biological samples on the protein level, which will have a major impact to serve the cause of diagnostic markers. Serum peptides and proteins are immobilized on derivatized carbon nanotubes, which function as binding material. Protein-loaded suspension is placed on a stainless steel target or buckypaper on aluminum target for direct analysis with MALDI-MS. The elution method to wash the bound proteins from carbon nanotubes was employed to compare with the direct analysis procedure. Elution is carried out by MALDI matrix solution to get them out of the entangled nanotubes, which are difficult to desorb by laser due to the complex nanotube structures. The advantage of these optimized methods compared to the conventional screening methods is the improved sensitivity, selectivity and the short analysis time without prior albumin and immunoglobulin depletion. The comparison of similarly modified diamond and carbon nanotubes exhibit differences in their nature to bind the proteins out of serum due to the differences in their physical characteristics. Infrared (IR) spectroscopy provided hint for the presence of tertiary amine peak at the crucial chemical step of iminodiacetic acid addition to acid chloride functionality on carbon nanotubes. Atomic absorption spectroscopy (AAS) was utilized to quantitatively measure the copper capacity of these derivatized carbon nanotubes which is a direct measure of capacity of

High-protein diet modifies colonic microbiota and luminal environment but not colonocyte metabolism in the rat model: the increased luminal bulk connection.

Science.gov (United States)

Liu, Xinxin; Blouin, Jean-Marc; Santacruz, Arlette; Lan, Annaïg; Andriamihaja, Mireille; Wilkanowicz, Sabina; Benetti, Pierre-Henri; Tomé, Daniel; Sanz, Yolanda; Blachier, François; Davila, Anne-Marie

2014-08-15

High-protein diets are used for body weight reduction, but consequences on the large intestine ecosystem are poorly known. Here, rats were fed for 15 days with either a normoproteic diet (NP, 14% protein) or a hyperproteic-hypoglucidic isocaloric diet (HP, 53% protein). Cecum and colon were recovered for analysis. Short- and branched-chain fatty acids, as well as lactate, succinate, formate, and ethanol contents, were markedly increased in the colonic luminal contents of HP rats (P diet, whereas the amount of butyrate in feces was increased (P diet consumption allows maintenance in the luminal butyrate concentration and thus its metabolism in colonocytes despite modified microbiota composition and increased substrate availability. Copyright © 2014 the American Physiological Society.

Single patient doses of {sup 99m}Tc-HDP: Assessment of radiochemical purity, sterility and extractables from a polypropylene syringe over six hours

Energy Technology Data Exchange (ETDEWEB)

Parkes, S.L.; Varelis, P. [St George Hospital, Kogarah, NSW (Australia). Department of Nuclear Medicine

1997-12-01

Full text: The purpose of this investigation was to determine the radiochemical purity (RCP), sterility and extractables for {sup 99m}Tc oxidronate ({sup 99m}Tc-HDP) stored in polypropylene syringes over < six-hour period. The radiochemical purity was determined using a two-strip ITLC procedure, performed at time 0, 1, 2, 4, 6 hours. The sterility and endotoxin levels were tested by a NATA accredited laboratory, after allowing the radiopharmaceutical to stand at room temperature for six hours in the syringes. Plasticisers and other likely compounds that could be extracted from the syringes into the aqueous solution were determined by high pressure liquid chromatography (HPLC) diode array detection. This analysis involved shaking normal saline in a syringe over night and then injecting an aliquot of this solution onto a C18 analytical column and monitoring the effluent at 200 and 253 nm. The radiochemical purity of {sup 99m}Tc-HDP did not significantly change over the course of the study and remained above the recommended RCP for this radiopharmaceutical. Furthermore, at six hours the RCP of {sup 99m}Tc-HDP stored in both the manufacturer`s vial and a syringe were identical. Sterility testing of {sup 99m}Tc-HDP stored in syringes showed no microbial growth and less than 10 endotoxin units/mL (pass). The HPLC analysis did not show the presence of any extraneous compounds in the aqueous solution. Single patient doses of {sup 99m}Tc-HDP stored in polypropylene syringes over a six-hour period fulfill all the quality control requirements for administration to humans.

Radiochemical determination of the neutron capture cross sections of {sup 241}Am irradiated in the JMTR reactor

Energy Technology Data Exchange (ETDEWEB)

Shinohara, N.; Hatsukawa, Y.; Hata, K.; Kohno, N. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1997-03-01

The thermal neutron capture cross section {sigma}{sub 0} and Resonance integral I{sub 0} of {sup 241}Am leading to the production of {sup 242m}Am and {sup 242g}Am were measured by radiochemical method. The cross sections obtained in this study are {sigma}{sub 0}=60.9 {+-} 2.6 barn, I{sub 0}=213 {+-} 13 barn for {sup 241}Am(n,{gamma}){sup 242m}Am and {sigma}{sub 0}=736 {+-} 31 barn, I{sub 0}=1684 {+-} 92 barn for {sup 241}Am(n,{gamma}){sup 242g}Am. (author)

Pollution of agricultural crops with lanthanides, thorium and uranium studied by instrumental and radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Kucera, J.; Mizera, J.; Randa, Z.; Vavrova, M.

2007-01-01

The lanthanide elements, Th and U were measured in soils and agricultural crops collected in an area polluted by emissions from a phosphate fertilizer plant. Concentrations of the above elements in the soil and crop samples were determined by instrumental neutron activation analysis (INAA). Selected crop samples were also analyzed using radiochemical neutron activation analysis (RNAA) based on alkaline-oxidative fusion of the irradiated samples followed by precipitation of REE oxalates. Elevated levels of lanthanides, Th and U were found in some samples, especially in wheat chaff and parsley. (author)

Radiochemical synthesis of 3-(4-[18F] Fluorophenyl)-8-hydroxy-1, 2, 3, 4-tetrahydrochromeno [3, 4-c] pyridin-5-one: A putative dopamine D$4 receptor PET imaging agent

International Nuclear Information System (INIS)

Li, G.C.; Yin, D.Z.; Wang, M.W.; Cheng, D.F.; Wang, Y.X.

2005-01-01

Introduction: The dopamine D 4 receptor has lately received increasing interest since it has been hypothesized to be involved in the pathology and pharmacotherapy of schizophrenia. While this receptor is expressed in lower density in various extrastriatal brain regions and its distribution is still unclear due to the lack of suitable imaging agent and its level change in schizophrenia is controversial. Herein, based on the structure-activity analysis of chromeno[3, 4-c]pyridine- 5-ones as potential dopamine D 4 receptor ligands, a putative D 4 subtype positron emission tomography (PET) radioligand, 3-(4-[ 18 F]fluorophenyl)-8-hydroxy-1, 2, 3, 4-tetrahydrochromeno [3, 4-c]pyridin-5-one ([ 18 F]FHTP), was designed and synthesized. Methods: The radiochemical synthesis route was shown in Figure 1. [ 18 F]Fluoride was produced with a Cyclone-30 (IBA, Belgium) by 18 O(p, n) 18 F reaction using enriched 18 O-H 2 O and eluted from a Dowex 1-X8 anion-exchange column with aqueous potassium carbonate (20 mg/mL). 4-[ 18 F]Fluorobenzaldehyde was prepared according to the method reported by Alan A. Wilson and et al.. Then, 8-hydroxy-1, 2, 3, 4-tetrahydrochromeno [3, 4-c]pyridin-5-one, sodium cyanoborohydride, methanol and acetic acid were added to the dry residue, The mixture was then sealed and heated at 120 degree C for 12 min. At the end of the reaction, the mixture was cooled, diluted with ethyl acetate and washed with water. The extracted organic layer was passed through a small anhydrous magnesium sulfate column. After removal of the solvents in the mixture at 50 degree C under a stream of nitrogen, the obtained residue was redissolved in methanol and purified with a semi-preparative HPLC system, then the desired product was collected. Results: The radiochemical synthesis of [ 18 F]FHTP took around 110 min at EOS with an overall radiochemical yield 19% (decay-corrected) and its radiochemical purity was higher than 95%. Conclusion: A presumed dopamine D 4 receptor PET

Direct and indirect radioiodination of protein: comparative study of chemotactic peptide labeling; Radioiodacao de proteina por via direta e indireta: estudo comparativo da marcacao de peptideo quimiotatico

Energy Technology Data Exchange (ETDEWEB)

Lavinas, Tatiana

2004-07-01

The development of simple methods for protein radioiodination have stimulated the use of radioiodinated peptides in vivo. There are two basic methods for labeling proteins with radioiodine: direct labeling, reaction of an electrophilic radioiodine with functional activated groups on protein, like the phenol ring in the tyrosine residue, and the conjugation of a previously radioiodinated molecule to the protein, referred as indirect method. The great problem related to the direct radioiodination of proteins is the in vivo dehalogenation. This problem can be minimized if a non-phenolic prosthetic group is used in the indirect radioiodination of the peptide. The ATE prosthetic group, N-succinimidyl 3-(tri-n-butylstannyl) benzoate, when radioiodinated by electrophilic iododestannilation produces N-succinimidyl 3-[{sup 123}l/{sup 131}l] iodine benzoate (SIB) that is subsequently conjugated to the protein by the acylation of the lysine group. There are many radiopharmaceuticals employed in scintigraphic images of infection and inflammation used with some limitations. These limitations stimulated the improvement of a new class of radiopharmaceuticals, the receptor-specific related labeled peptides, as the mediators of the inflammatory response, that presents high affinity by receptors expressed in the inflammation process, and fast clearance from blood and non-target tissues. One of these molecules is the synthetic chemotactic peptide fNleLFNIeYK that presents potent chemotaxis for leukocytes, with high affinity by the receptors presented in polymorphonuclear leukocytes and mononuclear phagocytes. The objective of this work included the synthesis of ATE prosthetic group and comparative radioiodination of the chemotactic peptide fNleLFNIeYK by direct and indirect methods, with radiochemical purity determination and evaluation of in vivo and in vitro stability of the compounds. This work presented an original contribution in the comparative biological distribution studies

Adhesion of Trypanosoma cruzi trypomastigotes to fibronectin or laminin modifies tubulin and paraflagellar rod protein phosphorylation.

Directory of Open Access Journals (Sweden)

Eliciane C Mattos

Full Text Available BACKGROUND: The unicellular parasite Trypanosoma cruzi is the causative agent of Chagaś disease in humans. Adherence of the infective stage to elements of the extracellular matrix (ECM, as laminin and fibronectin, is an essential step in host cell invasion. Although members of the gp85/TS, as Tc85, were identified as laminin and fibronectin ligands, the signaling events triggered on the parasite upon binding to these molecules are largely unexplored. METHODOLOGY/PRINCIPAL FINDINGS: Viable infective parasites were incubated with laminin, fibronectin or bovine serum albumin for different periods of time and the proteins were separated by bidimensional gels. The phosphoproteins were envisaged by specific staining and the spots showing phosphorylation levels significantly different from the control were excised and identified by MS/MS. The results of interest were confirmed by immunoblotting or immunoprecipitation and the localization of proteins in the parasite was determined by immunofluorescence. Using a host cell-free system, our data indicate that the phosphorylation contents of T. cruzi proteins encompassing different cellular functions are modified upon incubation of the parasite with fibronectin or laminin. CONCLUSIONS/SIGNIFICANCE: Herein it is shown, for the first time, that paraflagellar rod proteins and α-tubulin, major structural elements of the parasite cytoskeleton, are predominantly dephosphorylated during the process, probably involving the ERK1/2 pathway. It is well established that T. cruzi binds to ECM elements during the cell infection process. The fact that laminin and fibronectin induce predominantly dephosphorylation of the main cytoskeletal proteins of the parasite suggests a possible correlation between cytoskeletal modifications and the ability of the parasite to internalize into host cells.

Silica-gel modified with zirconium oxide as a novel 99Mo adsorbent 99mTc generators

International Nuclear Information System (INIS)

Salehi, H.; Mollarazi, E.; Abbasi, H.

2010-01-01

A new 99 Mo adsorbent has been prepared with modified silica gel with zirconium oxide (SiO 2 /ZrO 2 :Na 2 MoO 4 ) and used in technetium-99m generator. The adsorption behaviors of 99 Mo in the form of molybdate and 99m Tc in the form of pertechnetate on the new adsorbent was investigated showed that the adsorption capacity of molybdate on this generator was considerably higher than the usual generator with alumina column. Coating zirconium oxide on the surface of silica gel resulted in higher 99 Mo adsorption of this compound. 99m Tc is eluted with 0.9% NaCl, and the radionuclidic, radiochemical and chemical purities of the eluate were checked. This generator has a great potential as compared to the traditional alumina generators.

40 CFR 174.505 - Bacillus thuringiensis modified Cry3A protein (mCry3A) in corn; exemption from the requirement of...

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis modified Cry3A protein (mCry3A) in corn; exemption from the requirement of a tolerance. 174.505 Section 174.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PROCEDURES AND REQUIREMENTS FOR PLANT-INCORPORATED PROTECTANTS...

Determination of hydrophobic coenzyme a esters and other lipids using a biosensor comprising a modified coenzyme a- and acyl-coa binding protein (acbp)

DEFF Research Database (Denmark)

2002-01-01

, food and feed preparations, tissue extracts, acyl-CoA synthetase reaction media and various laboratory conditions using a modified Coenzyme A- and acyl-CoA binding protein (ACBP) is provided. Furthermore the invention relates to a construct comprising a peptide and a signal moiety for performing...

Increase of the radiochemical purity of aqueous solutions of compounds labelled with 131I using a ClAg sterile column

International Nuclear Information System (INIS)

Pliego, O.H.; Mitta, A.E.A.

1980-01-01

The use of a C1Ag sterile column that may be easily assembled at any nuclear medical center is proposed. The column is easy to handle and allows to obtain aqueous solutions of compounds labelled with radioactive iodine, with a radiochemical purity greater than 99%, conserving pH values, activity concentration, apyretogenia and sterility, the controls of toxicity and presence of heavy metals being negative. (C.A.K) [es

IN-MACA-MCC: Integrated Multiple Attractor Cellular Automata with Modified Clonal Classifier for Human Protein Coding and Promoter Prediction

Directory of Open Access Journals (Sweden)

Kiran Sree Pokkuluri

2014-01-01

Full Text Available Protein coding and promoter region predictions are very important challenges of bioinformatics (Attwood and Teresa, 2000. The identification of these regions plays a crucial role in understanding the genes. Many novel computational and mathematical methods are introduced as well as existing methods that are getting refined for predicting both of the regions separately; still there is a scope for improvement. We propose a classifier that is built with MACA (multiple attractor cellular automata and MCC (modified clonal classifier to predict both regions with a single classifier. The proposed classifier is trained and tested with Fickett and Tung (1992 datasets for protein coding region prediction for DNA sequences of lengths 54, 108, and 162. This classifier is trained and tested with MMCRI datasets for protein coding region prediction for DNA sequences of lengths 252 and 354. The proposed classifier is trained and tested with promoter sequences from DBTSS (Yamashita et al., 2006 dataset and nonpromoters from EID (Saxonov et al., 2000 and UTRdb (Pesole et al., 2002 datasets. The proposed model can predict both regions with an average accuracy of 90.5% for promoter and 89.6% for protein coding region predictions. The specificity and sensitivity values of promoter and protein coding region predictions are 0.89 and 0.92, respectively.

Chemical and radiochemical control of the primary circuit of Atucha INPP (Nuclear Power Plant) since the start up in January 1990

International Nuclear Information System (INIS)

Ali, S.P; Baungartner, E.C.; Blesa, M.A.

1990-01-01

Since the start up of Atucha I Nuclear Power Plant in January 1990, an exhaustive chemical and radiochemical control of primary media was undertaken. The main objectives were the evaluation of the water condition after the long outage and the determination of activity measurements limitations to detect and localize fuel failures. Chemical and radiochemical techniques were critically proved. At the same time, a complete program of updating and optimization of those procedures was developed, including the revision of the analytical parameters, range of applicability and accuracy. A more adequate processing of data was adopted. They were compared with historical values corresponding to periods with and without fuel elements failures, used as references. The analysis of theoretical models of total gamma activity concentration and some specific radionuclides activity concentration evolution and their rates, and the comparison with experimental data obtained during normal operation including some failure events, generated tables of alarm criteria through a combination of parameters. Additionally, actions are suggested for different combination of parameters. Operative conditions that might interfere in the detection and localization of a failed fuel element are also pointed out. (Author)

[Genetically modified food--great unknown].

Science.gov (United States)

Cichosz, G; Wiackowski, S K

2012-08-01

Genetically modified food (GMF) creates evident threat to consumers' health. In spite of assurances of biotechnologists, DNA of transgenic plants is instable, so, synthesis of foreign, allergenic proteins is possible. Due to high trypsin inhibitor content the GMF is digested much more slowly what, alike Bt toxin presence, increases probability of alimentary canal diseases. Next threats are bound to the presence of fitoestrogens and residues of Roundup pesticide, that can diminish reproductiveness; and even lead to cancerogenic transformation through disturbance of human hormonal metabolism. In spite of food producers and distributors assurances that food made of GMF raw materials is marked, de facto consumers have no choice. Moreover, along the food law products containing less than 0.9% of GMF protein are not included into genetically modified food.

Determination of rhenium in biological and environmental samples by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Kucera, J.; Mizera, J.; Randa, Z.; Byrne, A.R.; Lucanikova, M.

2006-01-01

Radiochemical neutron activation procedures using liquid-liquid extraction with tetraphenylarsonium chloride in chloroform from 1 M HCl and solid extraction with ALIQUAT 336 incorporated in a polyacrylonitrile binding matrix from 0.1 M HCl were developed for accurate determination of rhenium in biological and environmental samples at the sub-ng.g -1 level. Concentrations of Re in the range of 0.1 to 2.4 ng.g -1 were determined in several botanical reference materials (RM), while in a RM of road dust a value of approx. 10 ng.g -1 was found. Significantly elevated values of Re, up to 90 ng.g -1 , were found in seaweed (brown algae). Results for Re in the brown algae Fucus vesiculosus in which elevated 99 Tc values had previously been determined suggest possible competition between Re and Tc in the accumulation process. (author)

Use of new composite materials for the determination of Cu, Cd, Mo, As, and Sb in biological samples by radiochemical neutron activation analysis

Czech Academy of Sciences Publication Activity Database

Lučaníková, M.; Kučera, Jan; Šebesta, F.; John, J.

2006-01-01

Roč. 269, č. 2 (2006), s. 463-468 ISSN 0236-5731 R&D Projects: GA ČR(CZ) GA203/04/0943 Institutional research plan: CEZ:AV0Z10480505 Keywords : radiochemical neutron activation analysis * separation using composite materials Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.509, year: 2006

Radiochemical separation and effective dose estimation due to ingestion of 90Sr

International Nuclear Information System (INIS)

Ilic, Z.; Vidic, A.; Deljkic, D.; Sirko, D.; Zovko, E.; Samek, D.

2009-01-01

Since 2007. Institute for Public Health of Federation of Bosnia and Herzegovina-Radiation Protection Centre, within the framework of monitoring of radioactivity of environment carried out measurement of specific activity of 90 Sr content in selected food and water samples. The paper described the methods of measurement and radiochemical separation. Presented results, as average values of specific activity of 90 Sr, were used for estimation of effective dose due to ingestion of 90 Sr for 2007. and 2008. Estimated effective dose for 2007. due to ingestion of 90 Sr for adults was 1,36 μSv and 2,03 μSv for children (10 year old), and for 2008. 0,67 μSv (adults) and 1,01 μSv (children 10 year old). Estimated effective doses for 2007. and 2008. are varied because of different average specific activity radionuclide 90 Sr in selected samples of food, their number, species and origin. (author) [sr

Method Development of Cadmium Investigation in Rice by Radiochemical Neutron Activation Analysis

International Nuclear Information System (INIS)

Promsawad, Arunee; Pareepart, Ratirot; Laoharojanaphand, Sirinart; Arunee, Kongsakpaisal

2007-08-01

Full text: A radiochemical neutron activation analysis for the determination of cadmium was investigated. A chemical separation of cadmium utilized ion exchange chromatography of a strong basic anion-exchange resin BIO-RAD 1X 8 (Chloride form). The adsorbing medium of 2M HCl was found to be the most suitable among the concentration attempted (2, 4, 6, 8 and 10M HCl) and the eluent for desorption of the cadmium from column was 8M NH 3 solution. A chemical yield of 95% was found. The method has been evaluated by analyzing certified reference materials with 0.5.g/g (SRM 1577b, Bovine Liver) and 2.48.g/g (SRM 1566b, Oyster Tissue) cadmium. The agreement of the result with certified values is within 92% for Bovine Liver and 96% for Oyster Tissue. The method developed was applied to determine the cadmium concentrations in contaminated Thai rice. It was found that the cadmium concentrations ranged from 7.4 to 578.9 ppb

Development of Cy5.5-Labeled Hydrophobically Modified Glycol Chitosan Nanoparticles for Protein Delivery

Science.gov (United States)

Chin, Amanda

Therapeutic proteins are often highly susceptible to enzymatic degradation, thus restricting their in vivo stability. To overcome this limitation, delivery systems designed to promote uptake and reduce degradation kinetics have undergone a rapid shift from macro-scale systems to nanomaterial based carriers. Many of these nanomaterials, however, elicit immune responses and may have cytotoxic effects both in vitro and in vivo. The naturally derived polysaccharide chitosan has emerged as a promising biodegradable material and has been utilized for many biomedical applications; nevertheless, its function is often constrained by poor solubility. Glycol chitosan, a derivative of chitosan, can be hydrophobically modified to impart amphiphilic properties that enable the self-assembly into nanoparticles in aqueous media at neutral pH. This nanoparticle system has shown initial success as a therapeutic agent in several model cell culture systems, but little is known about its stability against enzymatic degradation. Therefore, the goal of this research was to investigate the resistance of hydrophobically modified glycol chitosan against enzyme-catalyzed degradation using an in vivo simulated system containing lysozyme. To synthesize the nanoparticles, hydrophobic cholanic acid was first covalently conjugated to glycol chitosan using of N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). Conjugates were purified by dialysis, lyophilized, and ultra-sonicated to form nanoparticles. Fourier transform infrared (FT-IR) spectroscopy confirmed the binding of 5beta-cholanic acid to the glycol chitosan. Particle size and stability over time were determined with dynamic light scattering (DLS), and particle morphology was evaluated by transmission electron microscopy (TEM). The average diameter of the nanoparticles was approximately 200 nm, which remained stable at 4°C for up to 10 days. Additionally, a near infrared fluorescent (NIRF) dye

Radiochemical data obtained by α spectrometry on unrecrystallized fossil coral samples from the Egyptian shoreline of the north-western Red Sea

International Nuclear Information System (INIS)

Choukri, A.; Hakam, O.K.; Reyss, J.L.; Plaziat, J.C.

2007-01-01

In this work, radiochemical results obtained by α spectrometry on 80 unrecrystallized fossil coral samples from the Egyptian shoreline of the north-western Red Sea are presented and discussed. The coral samples were collected in Egypt from the emerged 5e coral reef terraces over 500km from The Ras Gharib-Ras Shukeir depression (28 deg. 10 ' ) in the north to Wadi Lahami (north of Ras Banas, 24 deg. 10 ' ) in the south. The statistical description of radiochemical results (concentrations of U and Th radioisotopes, 234 U/ 238 U activity ratios and ages) obtained on a great number of coral samples showed that it is possible to establish methodological criterions which could be used to validate the measured ages before confronting them to the geological context of sampling sites. The obtained results confirm that the unrecrystallized corals ( 232 Th 238 U varies between 2.2 and 4.9ppm around an average of 3.18+/-0.65ppm. 234 U/ 238 U activity ratios are between 1.08 and 1.28 with an averaged value of 1.164+/-0.016 which exceeds that of present day sea water but which is in agreement with the ratio of 1.16 measured by a precise mass spectrometry in many Pleistocene coral samples. Except three samples dated at least 100ka, the radiochemical age of 5e coral samples vary between 108 and 131ka with an average value of 122.2ka and a standard deviation of 4.3ka. Except for samples from the Zeit area, the reef terrace is between 2 and 6m above the present sea level. This position is similar to the highest sea level from the last interglacial according to the glacio-isostatic rebound calculated for stable regions. This work proves that the large tectonic motions which affected the studied area after the Oligocene ceased after at least the last interglacial period

Distribution of plutonium in organs of extrapulmonary pool in remote periods after the beginning of inhalation in workers of radiochemical plant

International Nuclear Information System (INIS)

Suslova, K.G.; Khokhryakov, V.F.; Tokarskaya, Z.B.; Kudryavtseva, T.I.; Nifatov, A.P.

2000-01-01

Influence of the health state and some dosimetric factors on the distribution of systemic Pu for workers of radiochemical plants is studied. Data were obtained on results of radiochemical analysis of soft tissue and bone samples taken at autopsy from 591 workers of the radiochemical plant. Alpha activity was measured with a low background alpha-radiometer. The patho-morphological state of the liver was taken into account. It is shown that the health state and the grade of the pathological process have an effect upon distribution of systemic Pu in humans. Skeleton to liver ratio is 50.3 : 42.3 = 1.2 for the practically healthy people. As the state of the health worsens and the pathology becomes more scenic, resulting in the fatty degeneration in the hepatocytes, the fractions of Pu deposition in liver decreases, while the fraction in the skeleton increases in the same degree. The individuals with serious liver diseases (cancer, massive metastases in the liver, cirrhosis, alcoholism) have got the ratio the skeleton : the liver = 77.9 : 14.9 = 5.5. The correlation between the state of the state of the health, some domestic factor and the distribution of systemic Pu was studied using the multifactorial regression analysis. These results indicated that Pu redistribution between the liver and the skeleton is the reciprocal process. Under pathological processes the element released from the liver is transported to the skeleton. The intensity of Pu translocation from the liver to the skeleton is higher under pathological processes (28 % for 1 - 2 years) than under the normal life conditions (1.4 % y -1 ). It should be assumed that for the persons with different heavy chronic diseases the skeleton and liver exposure doses may differ from the calculated ones, if the doses are evaluated from the models that do not take into account the plutonium recycling in systemic organs under the pathological processes [ru

The application of transition metal ion chromatography to the determination of elemental and radiochemical species in PWR primary coolant

International Nuclear Information System (INIS)

Bridle, D.A.; Brown, G.R.; Johnson, P.A.V.

1992-01-01

The accurate determination of both elemental and radiochemical transition metal corrosion products, particularly cobalt and nickel, in PWR coolants is necessary if the transport mechanisms and their role in the development of out-of-core radiation fields are to be fully understood. AEA Technology, Winfrith, has collaborated for several years with a number of PWR utilities in Europe, developing advanced sampling and analytical techniques for the determination of both soluble and insoluble corrosion products in primary coolant. The design and installation of continuously flowing isokinetic capillary modifications to the existing sampling systems has been shown to be an effective method of providing a low, but representative, sample flow from high pressure systems for on-line determination of corrosion product species. Transition metal ion chromatography coupled with gamma-spectrometry has been used to determine both insoluble and soluble elemental and radiochemical species in reactor coolant, with particular attention being given to the determination of soluble elemental cobalt at levels as low as 1 ng per kg. Soluble species were determined directly following their concentration from up to 1 litre of coolant. Insoluble species collected on 0.45 micron filter membranes, following filtration of up to 1500 litres of coolant, were solubilised by fusion with potassium hydrogen sulphate before the application of ion chromatography. In each case the eluant from the chromatographic column was collected and the radionuclides determined by gamma-spectrometry

Advanced glycation end products-modified proteins and oxidized LDL mediate down-regulation of leptin in mouse adipocytes via CD36

International Nuclear Information System (INIS)

Unno, Yuka; Sakai, Masakazu; Sakamoto, Yu-ichiro; Kuniyasu, Akihiko; Nakayama, Hitoshi; Nagai, Ryoji; Horiuchi, Seikoh

2004-01-01

Advanced glycation end products (AGE)-modified proteins as well as oxidized-LDL (Ox-LDL) undergo receptor-mediated endocytosis by CHO cells overexpressing CD36, a member of class B scavenger receptor family. The purpose of the present study was to examine the effects of glycolaldehyde-modified BSA (GA-BSA) as an AGE-ligand and Ox-LDL on leptin expression in adipocytes. GA-BSA decreased leptin expression at both protein and mRNA levels in 3T3-L1 adipocytes and mouse epididymal adipocytes. Ox-LDL showed a similar inhibitory effect on leptin expression in 3T3-L1 adipocytes, which effect was protected by N-acetylcysteine, a reactive oxygen species (ROS) inhibitor. Binding of 125 I-GA-BSA or 125 I-Ox-LDL to 3T3-L1 adipocytes and subsequent endocytic degradation were inhibited by a neutralizing anti-CD36 antibody. Furthermore, this antibody also suppressed Ox-LDL-induced leptin down-regulation. These results clarify that the interaction of GA-BSA and Ox-LDL with CD36 leads to down-regulation of leptin expression via ROS system(s) in 3T3-L1 adipocytes, suggesting that a potential link of AGE- and/or Ox-LDL-induced leptin down-regulation might be linked to insulin-sensitivity in metabolic syndrome

Radiochemical analyses of surface water from U.S. Geological Survey hydrologic bench-mark stations

Science.gov (United States)

Janzer, V.J.; Saindon, L.G.

1972-01-01

The U.S. Geological Survey's program for collecting and analyzing surface-water samples for radiochemical constituents at hydrologic bench-mark stations is described. Analytical methods used during the study are described briefly and data obtained from 55 of the network stations in the United States during the period from 1967 to 1971 are given in tabular form.Concentration values are reported for dissolved uranium, radium, gross alpha and gross beta radioactivity. Values are also given for suspended gross alpha radioactivity in terms of natural uranium. Suspended gross beta radioactivity is expressed both as the equilibrium mixture of strontium-90/yttrium-90 and as cesium-137.Other physical parameters reported which describe the samples include the concentrations of dissolved and suspended solids, the water temperature and stream discharge at the time of the sample collection.

The effect of modifying dietary protein and carbohydrate in weight loss on arterial compliance and postprandial lipidemia in overweight women with polycystic ovary syndrome.

Science.gov (United States)

Moran, Lisa J; Noakes, Manny; Clifton, Peter M; Norman, Robert J

2010-11-01

In overweight women with polycystic ovary syndrome, weight loss improves arterial compliance and postprandial lipidemia. Modifying dietary carbohydrate or protein in weight loss provided similar improvements in arterial compliance and postprandial lipidemia. Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Characterization and Preparation of Broken Rice Proteins Modified by Proteases

Directory of Open Access Journals (Sweden)

Lixia Hou

2010-01-01

Full Text Available Broken rice is an underutilized by-product of milling. Proteins prepared from broken rice by treatments with alkaline protease and papain have been characterized with regard to nutritional and functional properties. The protein content and the protein recovery were 56.45 and 75.45 % for alkaline protease treatment, and 65.45 and 46.32 % for papain treatment, respectively. Protease treatment increased the lysine and valine content, leading to a more balanced amino acid profile. Broken rice proteins had high emulsifying capacity, 58.3–71.6 % at neutral pH, and adequate water holding capacity, ranging from 1.96 to 2.93 g/g of proteins. At pH=7.0, the broken rice protein had the highest water holding capacity and the best interfacial activities (emulsifying capacity, emulsifying stability, foaming capacity and foaming stability, which may be the result of the higher solubility at pH=7.0. The interfacial activities increased with the increase in the mass fraction of broken rice proteins. The proteins prepared by the papain treatment had higher water holding capacity (p>0.05, emulsifying capacity (p0.05 than alkaline protease treatment at the same pH or mass fraction. To test the fortification of food products with broken rice proteins, pork sausages containing the proteins were prepared. Higher yield of the sausages was obtained with the increased content of broken rice proteins, in the range of 2.0–9.0 %. The results indicate that broken rice proteins have potential to be used as the protein fortification ingredient for food products.

Manganese modified CdTe/CdS quantum dots as an immunoassay biosensor for the detection of Golgi protein-73.

Science.gov (United States)

Liu, Wei; Zhang, Aixia; Xu, Guanhong; Wei, Fangdi; Yang, Jing; Hu, Qin

2016-01-05

In this paper, a new fluorescence bioassay for Golgi protein-73 (GP73), a promising marker for monitoring liver tumor, was developed by using anti-GP73 antibody (GP73 Ab) capped quantum dots (QDs) coupled with protein A/G agarose beads in an attempt to improve the analysis time, cost and operation. First, carboxylic-functionalized Mn modified CdTe/CdS QDs were synthesized and covalently conjugated with GP73 Ab, then protein A/G agarose beads were specifically combined with the QDs-conjugated Ab to form the QDs-Ab-beads conjugate, which could capture and separate GP73 from the sample through simple centrifugation. It was found that the fluorescence intensity of the above QDs-Ab-beads biosensor could be specifically quenched by GP73 added. A simple, rapid and specific quantitative method for GP73 protein was proposed using the as-prepared QDs-Ab-beads as a biosensor. Under the optimized conditions, the calibration curve of the proposed assay showed good linearity with a correlation coefficient of 0.9935 in the concentration range of 20-150 ng/mL of GP73 protein. The limit of detection (defined as 3σ/K) was 10 ng/mL. The method built exhibited a great potential in the clinic test of GP73. Copyright © 2015 Elsevier B.V. All rights reserved.

A radiochemical assay for detection of leukotriene B4 production from isolated cells

International Nuclear Information System (INIS)

Aharony, D.; Dobson, P.; Krell, R.D.

1984-01-01

A radiochemical procedure for quantitating the effect of inhibitors of leukotriene B4 (LTB4) biosynthesis is described. Rat peritoneal cells were labeled with 3 H-arachidonic acid and stimulated with the calcium ionophore A23187. 3 H-LTB4 was isolated by processing on C18-Sep Pak cartridges followed by reverse-phase high pressure liquid chromatography (HPLC). The identity of this product, as well as other arachidonic acid metabolites, was verified by using silicic acid column chromatography followed by straight-phase HPLC and thin layer chromatography. Using this assay, LTB4 release by ionophore A23187 has been shown to be both time- and concentration-dependent. Indomethacin enhanced, while NDGA and ETYA inhibited, the A23187-induced production of LTB4. This procedure is both simple and direct and is capable of assessing the ability of novel compounds to alter LTB4 production

Toxicity assessment of modified Cry1Ac1 proteins and genetically ...

African Journals Online (AJOL)

Owner

2015-06-10

Jun 10, 2015 ... Key words: Modified Cry1Ac1, food safety assessment, toxicity, insect- resistant rice Agb0101. INTRODUCTION. Genetically modified (GM) crops are becoming an increasingly important feature of the agricultural land- scapes. In 2013, approximately 175 million hectares of. GM crops were planted by 18 ...

Identification of an intracellular protein that specifically interacts with photoaffinity-labeled oncogenic p21 protein

International Nuclear Information System (INIS)

Lee, G.; Ronai, Z.A.; Pincus, M.R.; Brandt-Rauf, P.W.; Weinstein, I.B.; Murphy, R.B.; Delohery, T.M.; Nishimura, S.; Yamaizumi, Z.

1989-01-01

An oncogenic 21-kDa (p21) protein (Harvey RAS protein with Val-12) has been covalently modified with a functional reagent that contains a photoactivatable aromatic azide group. This modified p21 protein has been introduced quantitatively into NIH 3T3 cells using an erythrocyte-mediated fusion technique. The introduced p21 protein was capable of inducing enhanced pinocytosis and DNA synthesis in the recipient cells. To identify the putative intracellular protein(s) that specifically interact with modified p21 protein, the cells were pulsed with [ 35 S]methionine at selected times after fusion and then UV-irradiated to activate the azide group. The resulting nitrene covalently binds to amino acid residues in adjacent proteins, thus linking the p21 protein to these proteins. The cells were then lysed, and the lysate was immunoprecipitated with the anti-p21 monoclonal antibody Y13-259. The immunoprecipitate was analyzed by SDS/PAGE to identify p21 - protein complexes. By using this technique, the authors found that three protein complexes of 51, 64, and 82 kDa were labeled specifically and reproducibly. The most prominent band is the 64-kDa protein complex that shows a time-dependent rise and fall, peaking within a 5-hr period after introduction of the p21 protein the cells. These studies provide evidence that in vitro the p21 protein becomes associated with a protein whose mass is about 43 kDa. They suggest that the formation of this complex may play a role in mediating early events involved with cell transformation induced by RAS oncogenes

High-protein diet differently modifies intestinal goblet cell characteristics and mucosal cytokine expression in ileum and colon.

Science.gov (United States)

Lan, Annaïg; Andriamihaja, Mireille; Blouin, Jean-Marc; Liu, Xinxin; Descatoire, Véronique; Desclée de Maredsous, Caroline; Davila, Anne-Marie; Walker, Francine; Tomé, Daniel; Blachier, François

2015-01-01

We have previously shown that high-protein (HP) diet ingestion causes marked changes in the luminal environment of the colonic epithelium. This study aimed to evaluate the impact of such modifications on small intestinal and colonic mucosa, two segments with different transit time and physiological functions. Rats were fed with either normal protein (NP; 14% protein) or HP (53% protein) isocaloric diet for 2 weeks, and parameters related to intestinal mucous-secreting cells and to several innate/adaptive immune characteristics (myeloperoxidase activity, cytokine and epithelial TLR expression, proportion of immune cells in gut-associated lymphoid tissues) were measured in the ileum and colon. In ileum from HP animals, we observed hyperplasia of mucus-producing cells concomitant with an increased expression of Muc2 at both gene and protein levels, reduction of mucosal myeloperoxidase activity, down-regulation of Tlr4 gene expression in enterocytes and down-regulation of mucosal Th cytokines associated with CD4+ lymphocyte reduction in mesenteric lymph nodes. These changes coincided with an increased amount of acetate in the ileal luminal content. In colon, HP diet ingestion resulted in a lower number of goblet cells at the epithelial surface but increased goblet cell number in colonic crypts together with an increased Muc3 and a slight reduction of Il-6 gene expression. Our data suggest that HP diet modifies the goblet cell distribution in colon and, in ileum, increases goblet cell activity and decreases parameters related to basal gut inflammatory status. The impact of HP diet on intestinal mucosa in terms of beneficial or deleterious effects is discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

A modified gelatin zymography technique incorporating total protein normalization.

Science.gov (United States)

Raykin, Julia; Snider, Eric; Bheri, Sruti; Mulvihill, John; Ethier, C Ross

2017-03-15

Gelatinase zymography is a commonly used laboratory procedure; however, variability in sample loading and concentration reduce the accuracy of quantitative results obtained from this technique. To facilitate normalization of gelatinase activity by loaded protein amount, we developed a protocol using the trihalocompound 2,2,2-trichloroethanol to allow for gelatin zymography and total protein labeling within the same gel. We showed that detected protein levels increased linearly with loading, and describe a loading concentration range over which normalized gelatinase activity was constant. We conclude that in-gel total protein detection is feasible in gelatin zymography and greatly improves comparison of gelatinase activity between samples. Published by Elsevier Inc.

Green methods for the radiochemical separations of no-carrier-added 61Cu, 62Zn from 7Li irradiated cobalt target

International Nuclear Information System (INIS)

Moumita Maiti; Kaustab Ghosh; Susanta Lahiri

2015-01-01

A nat Co target was irradiated with 47 MeV 7 Li beam to produce no-carrier-added 61 Cu, 62 Zn in the target matrix. Two new green radiochemical methods were developed for separation of 61 Cu and 62 Zn from the target matrix, (i) liquid-liquid extraction (LLX) technique using room temperature ionic liquid (RTIL) 1-butyl-3-methylimidazolium hexafluorophosphate ([C 4 mim][PF 6 ]) and ammonium pyrrolidinedithiocarbamate (APDC) (ii) adsorption on calcium alginate beads. (author)

Radio-iodide uptake by modified poly (glycidyl methacrylate) as anion exchange resin

Energy Technology Data Exchange (ETDEWEB)

Othman, Sameh H. [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Center; Atomic Energy Authority, Cairo (Egypt). Second Research Reactor; Elbarbary, Ahmed M. [Atomic Energy Authority, Cairo (Egypt). Radiation Research of Polymer Chemistry Dept.; Rashad, Ghada; Fasih, T.W. [Atomic Energy Authority, Cairo (Egypt). Hot Laboratories Center

2017-03-01

Poly(glycidyl methacrylate) (PGMA) microspheres were prepared by radiation induced polymerization of glycidyl methacrylate (GMA) monomer. The factors affecting the degree of polymerization and yield (%) of PGMA such as type of solvent, monomer concentration, and irradiation dose were investigated. It was found that the PGMA yield (%) increases with increasing monomer concentration up to 50% and absorbed dose of 5 kGy. The resulting PGMA containing the epoxy group was chemically modified by hydroxyl amine to act as anion-exchange resin for uptake of {sup 131}I{sup -} ions. The modified PGMA (MPGMA) was characterized by Fourier transform infrared (FT-IR) spectrophotometer, thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM). I-131 is produced from the fission of U-235 with low-enrichment uranium (LEU) targets in the Egyptian Second Research Reactor (ETRR-2). Separation of iodide from the radioactive solution by batchwise and column techniques was employed to determine the adsorption capacity of the MPGMA. Quality control of {sup 131}I product solution and radiochemical purity was examined by using the ascending paper chromatography method. The uptake behavior of MPGMA towards {sup 131}I{sup -} ions were studied at different experimental conditions and achieved by X-ray fluorescence (XRF). The synthesized MPGMA showed good results as anion-exchange and an effective adsorbent for uptaking {sup 131}I{sup -} ions.

Low-molecular weight protein profiling of genetically modified maize using fast liquid chromatography electrospray ionization and time-of-flight mass spectrometry.

Science.gov (United States)

Koc, Anna; Cañuelo, Ana; Garcia-Reyes, Juan F; Molina-Diaz, Antonio; Trojanowicz, Marek

2012-06-01

In this work, the use of liquid chromatography coupled to electrospray time-of-flight mass spectrometry (LC-TOFMS) has been evaluated for the profiling of relatively low-molecular weight protein species in both genetically modified (GM) and non-GM maize. The proposed approach consisted of a straightforward sample fractionation with different water and ethanol-based buffer solutions followed by separation and detection of the protein species using liquid chromatography with a small particle size (1.8 μm) C(18) column and electrospray-time-of-flight mass spectrometry detection in the positive ionization mode. The fractionation of maize reference material containing different content of transgenic material (from 0 to 5% GM) led to five different fractions (albumins, globulins, zeins, zein-like glutelins, and glutelins), all of them containing different protein species (from 2 to 52 different species in each fraction). Some relevant differences in the quantity and types of protein species were observed in the different fractions of the reference material (with different GM contents) tested, thus revealing the potential use of the proposed approach for fast protein profiling and to detect tentative GMO markers in maize. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fully automated synthesis of ¹¹C-acetate as tumor PET tracer by simple modified solid-phase extraction purification.

Science.gov (United States)

Tang, Xiaolan; Tang, Ganghua; Nie, Dahong

2013-12-01

Automated synthesis of (11)C-acetate ((11)C-AC) as the most commonly used radioactive fatty acid tracer is performed by a simple, rapid, and modified solid-phase extraction (SPE) purification. Automated synthesis of (11)C-AC was implemented by carboxylation reaction of MeMgBr on a polyethylene Teflon loop ring with (11)C-CO2, followed by acidic hydrolysis with acid and SCX cartridge, and purification on SCX, AG11A8 and C18 SPE cartridges using a commercially available (11)C-tracer synthesizer. Quality control test and animals positron emission tomography (PET) imaging were also carried out. A high and reproducible decay-uncorrected radiochemical yield of (41.0 ± 4.6)% (n=10) was obtained from (11)C-CO2 within the whole synthesis time about 8 min. The radiochemical purity of (11)C-AC was over 95% by high-performance liquid chromatography (HPLC) analysis. Quality control test and PET imaging showed that (11)C-AC injection produced by the simple SPE procedure was safe and efficient, and was in agreement with the current Chinese radiopharmaceutical quality control guidelines. The novel, simple, and rapid method is readily adapted to the fully automated synthesis of (11)C-AC on several existing commercial synthesis module. The method can be used routinely to produce (11)C-AC for preclinical and clinical studies with PET imaging. Copyright © 2013 Elsevier Ltd. All rights reserved.

Determination of trace amounts of uranium in silicate materials by means of neutron activation analysis involving rapid radiochemical separation

International Nuclear Information System (INIS)

Ebihara, M.; Tomura, Kenji; Masutani, M.

1987-01-01

Uranium is determined in silicate materials such as standard rocks and a meteorite by radiochemical neutron activation analysis. The gamma-ray intensity of 239 U was measured with a planar type pure germanium detector system. The obtained data are mostly consistent with the literature values. Compared with a non-destructive method, the present method was found to improve the sensitivity by at least a factor of ten. Several errors which might be involved in the authors' RNAA procedures were examined and their degrees were evaluated. (author)

Soy protein modification: A review

Directory of Open Access Journals (Sweden)

Barać Miroljub B.

2004-01-01

Full Text Available Soy protein products such as flour, concentrates and isolates are used in food formulation because of their functionality, nutritional value and low cost. To obtain their optimal nutritive and functional properties as well as desirable flavor different treatments are used. Soybean proteins can be modified by physical, chemical and enzymatic treatments. Different thermal treatments are most commonly used, while the most appropriate way of modifying soy proteins from the standpoint of safety is their limited proteolysis. These treatments cause physical and chemical changes that affect their functional properties. This review discusses three principal methods used for modification of soy protein products, their effects on dominant soy protein properties and some biologically active compounds.

Hydrologic conditions and distribution of selected radiochemical and chemical constituents in water, Snake River Plain aquifer, Idaho National Engineering Laboratory, Idaho, 1989 through 1991

International Nuclear Information System (INIS)

Bartholomay, R.C.; Orr, B.R.; Liszewski, M.J.; Jensen, R.G.

1995-08-01

Radiochemical and chemical wastewater discharged since 1952 to infiltration ponds and disposal wells at the Idaho National Engineering Laboratory (INEL) has affected water quality in the Snake River Plain aquifer. The U.S. Geological Survey, in cooperation with the U.S. Department of Energy, maintains a continuous monitoring network at the INEL to determine hydrologic trends and to delineate the movement of radiochemical and chemical wastes in the aquifer. This report presents an analysis of water-level and water-quality data collected from the Snake River Plain aquifer during 1989-91. Water in the eastern Snake River Plain aquifer moves principally through fractures and interflow zones in basalt, generally flows southwestward, and eventually discharges at springs along the Snake River. The aquifer is recharged principally from irrigation water, infiltration of streamflow, and ground-water inflow from adjoining mountain drainage basins. Water levels in wells throughout the INEL generally declined during 1989-91 due to drought. Detectable concentrations of radiochemical constituents in water samples from wells in the Snake River Plain aquifer at the INEL decreased or remained constant during 1989-91. Decreased concentrations are attributed to reduced rates of radioactive-waste disposal, sorption processes, radioactive decay, and changes in waste-disposal practices. Detectable concentrations of chemical constituents in water from the Snake River Plain aquifer at the INEL were variable during 1989-91. Sodium and chloride concentrations in the southern part of the INEL increased slightly during 1989-91 because of increased waste-disposal rates and a lack of recharge from the Big Lost River. Plumes of 1,1,1-trichloroethane have developed near the Idaho Chemical Processing Plant and the Radioactive Waste Management Complex as a result of waste disposal practices

Modulating Protein Adsorption on Oxygen Plasma Modified Polysiloxane Surfaces

International Nuclear Information System (INIS)

Marletta, G.

2006-01-01

In the present paper we report the study on the adsorption behaviour of three model globular proteins, Human Serum Albumin, Lactoferrin and Egg Chicken Lysozyme onto both unmodified surfaces of a silicon-based polymer and the corresponding plasma treated surfaces. In particular, thin films of hydrophobic polysiloxane (about 90 degree of static water contact angle, WCA) were converted by oxygen plasma treatment at reduced pressure into very hydrophilic phases of SiOx (WCA less than 5 degree). The kinetics of protein adsorption processes were investigated by QCM-D technique, while the chemical structure and topography of the protein adlayer have been studied by Angular resolved-XPS and AFM respectively. It turned out that Albumin and Lysozyme exhibited the opposite preferential adsorption respectively onto the hydrophobic and hydrophilic surfaces, while Lactoferrin did not exhibit significant differences. The observed protein behaviour are discussed both in terms of surface-dependent parameters, including surface free energy and chemical structure, and in terms of protein-dependent parameters, including charge as well as the average molecular orientation in the adlayers. Finally, some examples of differential adsorption behaviour of the investigated proteins are reported onto nanopatterned polysiloxane surfaces consisting of hydrophobic nanopores surrounded by hydrophilic (plasma-treated) matrix and the reverse

Radiostrontium accumulation in animal bones: development of a radiochemical method by ultra low-level liquid scintillation counting for its quantification.

Science.gov (United States)

Iammarino, Marco; Dell'Oro, Daniela; Bortone, Nicola; Mangiacotti, Michele; Chiaravalle, Antonio Eugenio

2018-03-31

Strontium-90 (90Sr) is a fission product, resulting from the use of uranium and plutonium in nuclear reactors and weapons. Consequently, it may be found in the environment as a consequence of nuclear fallouts, nuclear weapon testing, and not correct waste management. When present in the environment, strontium-90 may be taken into animal body by drinking water, eating food, or breathing air. The primary health effects are bone tumors and tumors of the blood-cell forming organs, due to beta particles emitted by both 90Sr and yttrium-90 (90Y). Moreover, another health concern is represented by inhibition of calcification and bone deformities in animals. Actually, radiometric methods for the determination of 90Sr in animal bones are lacking. This article describers a radiochemical method for the determination of 90Sr in animal bones, by ultra low-level liquid scintillation counting. The method precision and trueness have been demonstrated through validation tests (CV% = 12.4%; mean recovery = 98.4%). Detection limit and decision threshold corresponding to 8 and 3 mBecquerel (Bq) kg-1, respectively, represent another strong point of this analytical procedure. This new radiochemical method permits the selective extraction of 90Sr, without interferences, and it is suitable for radiocontamination surveillance programs, and it is also an improvement with respect to food safety controls.

Radiochemical tools at the experimental lakes area (ELA) in Ontario, Canada

International Nuclear Information System (INIS)

Pfitzner, J.; Brunskill, G.

1998-01-01

Full text: For over 20 years, Canadian research scientists have used radiochemical tracers added to remote and pristine lakes to study physical, chemical, and biological processes that could not be easily quantified by other methods. Lakes have also been manipulated by experimentally altering the hydrological cycle, chemical composition, and species of fish in selected lakes, and using companion lakes as controls. Varying additions of organic carbon, N, and P have been done, and the exchange rate of carbon dioxide between the atmosphere and water was estimated using radon evasion rates from radium spikes in the lake water. Multinuclide spikes were done to follow the path of mine waste elements through the food chain and sediment accumulation. Lakes were experimentally acidified with HCl and HNO 3 and H 2 SO 4 to simulate acid rain, and to study natural buffering capacity of the hydrological cycle. Some of this research has been used to legislate pollution control in the St. Laurence Great Lakes and across Canada and USA. ELA research team spirit has survived several forest fires, bear attacks on the kitchen, massive cut-backs in funding and reduction in staff of Fisheries and Ocean Canada

Identification of an intracellular protein that specifically interacts with photoaffinity-labeled oncogenic p21 protein.

Science.gov (United States)

Lee, G; Ronai, Z A; Pincus, M R; Brandt-Rauf, P W; Murphy, R B; Delohery, T M; Nishimura, S; Yamaizumi, Z; Weinstein, I B

1989-11-01

An oncogenic 21-kDa (p21) protein (Harvey RAS protein with Val-12) has been covalently modified with a functional reagent that contains a photoactivatable aromatic azide group. This modified p21 protein has been introduced quantitatively into NIH 3T3 cells using an erythrocyte-mediated fusion technique. The introduced p21 protein was capable of inducing enhanced pinocytosis and DNA synthesis in the recipient cells. To identify the putative intracellular protein(s) that specifically interact with the modified p21 protein, the cells were pulsed with [35S]methionine at selected times after fusion and then UV-irradiated to activate the azide group. The resulting nitrene covalently binds to amino acid residues in adjacent proteins, thus linking the p21 protein to these proteins. The cells were then lysed, and the lysate was immunoprecipitated with the anti-p21 monoclonal antibody Y13-259. The immunoprecipitate was analyzed by SDS/PAGE to identify p21-protein complexes. By using this technique, we found that three protein complexes of 51, 64, and 82 kDa were labeled specifically and reproducibly. The most prominent band is the 64-kDa protein complex that shows a time-dependent rise and fall, peaking within a 5-hr period after introduction of the p21 protein into the cells. These studies provide evidence that in vitro the p21 protein becomes associated with a protein whose mass is about 43 kDa. We suggest that the formation of this complex may play a role in mediating early events involved with cell transformation induced by RAS oncogenes.

Determination of isotopic ratios of osmium and ruthenium in meteorites by pretreatment and radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Chinfang Chai; Yongzhong Liu; Xueying Mao

1996-01-01

The isotopic abundance ratios of 190 Os/ 184 Os and 96 Ru/ 102 Ru for the metal phases of the Jilin and Taonan stone meteorites were determined by pretreatment and radiochemical neutron activation analysis. All experimental factors affecting Os and Ru isotopic ratios were discussed, including sampling, standard, irradiation, separation and counting. The statistical errors of measurements for the 199 Os/ 184 Os ratio can be controlled within 1%. The experimental results indicate that the statistically significant anomalies of the 190 Os/ 184 Os and 96 Ru/ 102 Ru ratios have not been found relative to the terrestrial Os and Ru standards. (author). 6 refs., 1 fig., 5 tabs

Selective detection and quantification of modified DNA with solid-state nanopores.

Science.gov (United States)

Carlsen, Autumn T; Zahid, Osama K; Ruzicka, Jan A; Taylor, Ethan W; Hall, Adam R

2014-10-08

We demonstrate a solid-state nanopore assay for the unambiguous discrimination and quantification of modified DNA. Individual streptavidin proteins are employed as high-affinity tags for DNA containing a single biotin moiety. We establish that the rate of translocation events corresponds directly to relative concentration of protein-DNA complexes and use the selectivity of our approach to quantify modified oligonucleotides from among a background of unmodified DNA in solution.

Modifier genes: Moving from pathogenesis to therapy.

Science.gov (United States)

McCabe, Edward R B

2017-09-01

This commentary will focus on how we can use our knowledge about the complexity of human disease and its pathogenesis to identify novel approaches to therapy. We know that even for single gene Mendelian disorders, patients with identical mutations often have different presentations and outcomes. This lack of genotype-phenotype correlation led us and others to examine the roles of modifier genes in the context of biological networks. These investigations have utilized vertebrate and invertebrate model organisms. Since one of the goals of research on modifier genes and networks is to identify novel therapeutic targets, the challenges to patient access and compliance because of the high costs of medications for rare genetic diseases must be recognized. A recent article explored protective modifiers, including plastin 3 (PLS3) and coronin 1C (CORO1C), in spinal muscular atrophy (SMA). SMA is an autosomal recessive deficit of survival motor neuron protein (SMN) caused by mutations in SMN1. However, the severity of SMA is determined primarily by the number of SMN2 copies, and this results in significant phenotypic variability. PLS3 was upregulated in siblings who were asymptomatic compared with those who had SMA2 or SMA3, but identical homozygous SMN1 deletions and equal numbers of SMN2 copies. CORO1C was identified by interrogation of the PLS3 interactome. Overexpression of these proteins rescued endocytosis in SMA models. In addition, antisense RNA for upregulation of SMN2 protein expression is being developed as another way of modifying the SMA phenotype. These investigations suggest the practical application of protective modifiers to rescue SMA phenotypes. Other examples of the potential therapeutic value of novel protective modifiers will be discussed, including in Duchenne muscular dystrophy and glycerol kinase deficiency. This work shows that while we live in an exciting era of genomic sequencing, a functional understanding of biology, the impact of its

Groundwater quality in wells in central rural Finland: a microbiological and radiochemical survey

International Nuclear Information System (INIS)

Korhonen, L.; Niskanen, M.; Heinonen-Tanski, H.; Martikainen, P.J.; Salonen, L.; Taipalinen, I.

1996-01-01

The microbiological, physicochemical, and radiochemical water quality from samples of 150 rural wells in Finland was analyzed. Organic matter exceeded 12 mg KMnO4 L(-1) in 63% and nitrate 25 mg NO3 L(-1) in 29% of the wells. NO3--concentrations were higher in wells with cattle. Fecal coliforms and fecal streptococci were found in 10-40%. There was no direct positive correlation between heterotrophic and indicator bacteria. Salmonella or Campylobacter were not detected. Human pathogen Listeria monocytogenes was isolated from two and Yersinia enterocolitica serotypes O5 or O6 from four waters not containing fecal coliforms. Thus, the predictive value of fecal coliforms to indicate these pathogens is poor. Coliphages were found in seven wells. Mean concentrations of radon and long-lived alpha-active radionuclides were lower and those of beta-emitting radionuclides higher than the mean concentrations measured from groundwater in Finland. Radionuclides from the Chernobyl fallout were not detected

On-Line Monitoring for Control and Safeguarding of Radiochemical Streams at Spent Fuel Reprocessing Plant

International Nuclear Information System (INIS)

Bryan, Samuel A.; Levitskaia, Tatiana G.; Billing, Justin M.; Casella, Amanda J.; Johnsen, Amanda M.; Peterson, James M.

2009-01-01

Advanced techniques enabling enhanced safeguarding of the spent fuel reprocessing plants are urgently needed. Our approach is based on prerequisite that real time monitoring of the solvent extraction flowsheets provides unique capability to quickly detect unwanted manipulations with fissile isotopes present in the radiochemical streams during reprocessing activities. The methods used to monitor these processes must be robust and must be able to withstand harsh radiation and chemical environments. A new on-line monitoring system satisfying these requirements and featuring Raman spectroscopy combined with a Coriolis and conductivity probes, has been recently developed by our research team. It provides immediate chemical data and flow parameters of high-level radioactive waste streams with high brine content generated during retrieval activities from Hanford nuclear waste storage tanks. The nature of the radiochemical streams at the spent fuel reprocessing plant calls for additional spectroscopic information, which can be gained by the utilization of UV-vis-NIR capabilities. Raman and UV-vis-NIR spectroscopies are analytical techniques that have extensively been extensively applied for measuring the various organic and inorganic compounds including actinides. The corresponding spectrometers used under the laboratory conditions are easily convertible to the process-friendly configurations allowing remote measurements under the flow conditions. A fiber optic Raman probe allows monitoring of the high concentration species encountered in both aqueous and organic phases within the UREX suite of flowsheets, including metal oxide ions, such as uranyl, components of the organic solvent, inorganic oxo-anions, and water. The actinides and lanthanides are monitored remotely by UV-vis-NIR spectroscopy in aqueous and organic phases. In this report, we will present our recent results on spectroscopic measurements of simulant flowsheet solutions and commercial fuels available at

Application of radiochemical methods for development of new biological preparation designed for soil bioremediation

International Nuclear Information System (INIS)

Kim, A.A.; Djuraeva, G.T.; Djumaniyazova, G.I.; Yadgarov, Kh.T.

2006-01-01

Full text: Internationally the bioremediation of agricultural lands contaminated by persistent chloroorganic compounds by means of the microbial methods are used as the most low-cost and the most effective. One of the factors reducing efficacy of microbial degradation, is often the low quantity of microorganisms - destructors in the soil. Therefore, we have designed bioremediation technology of soils, contaminated by organochlorine compounds, with use of the alive microorganisms as active agent. We developed the biological preparation containing 5 aboriginal active strains of bacteria - destructors of persistent chloroorganic compounds and investigated the ability of biological preparation to increase the bioremediation potential of contaminated soils. To carry out the investigation we developed the complex of radiochemical methods with use of tritium labeled PCBs, including the following methods: 1.The method to define the accumulation and degradation of PCBs in soil bacteria in culture allows determination of quantitative characteristics of bacterial strains. 2. The method to define the PCBs degradation by soil bacteria strains in model conditions in the soil allows to estimate the PCB-destructive activity of strains after introducing in soil. 3. A method to define the PCB-destructive activity of own microbiota of contaminated soil. 4. A method to define the effect of stimulation of the PCB-destructive activity of biological preparation and own microbiota of soil with the help of biofertilizers. By using the developed radiochemical methods we have carried out investigation on creation of new biological preparation on the basis of strains of soil bacteria - destructors of PCBs. We also determined the quality and quantity characteristics of HCCH and PCBs-destructive activity of new biological preparation. It is shown that the new biological preparation is capable of accumulation and destruction of the PCBs in culture and in soil at model conditions. Thus, the

Bioinformatics analysis to assess potential risks of allergenicity and toxicity of HRAP and PFLP proteins in genetically modified bananas resistant to Xanthomonas wilt disease.

Science.gov (United States)

Jin, Yuan; Goodman, Richard E; Tetteh, Afua O; Lu, Mei; Tripathi, Leena

2017-11-01

Banana Xanthomonas wilt (BXW) disease threatens banana production and food security throughout East Africa. Natural resistance is lacking among common cultivars. Genetically modified (GM) bananas resistant to BXW disease were developed by inserting the hypersensitive response-assisting protein (Hrap) or/and the plant ferredoxin-like protein (Pflp) gene(s) from sweet pepper (Capsicum annuum). Several of these GM banana events showed 100% resistance to BXW disease under field conditions in Uganda. The current study evaluated the potential allergenicity and toxicity of the expressed proteins HRAP and PFLP based on evaluation of published information on the history of safe use of the natural source of the proteins as well as established bioinformatics sequence comparison methods to known allergens (www.AllergenOnline.org and NCBI Protein) and toxins (NCBI Protein). The results did not identify potential risks of allergy and toxicity to either HRAP or PFLP proteins expressed in the GM bananas that might suggest potential health risks to humans. We recognize that additional tests including stability of these proteins in pepsin assay, nutrient analysis and possibly an acute rodent toxicity assay may be required by national regulatory authorities. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Genetically modified foods and allergy.

Science.gov (United States)

Lee, T H; Ho, H K; Leung, T F

2017-06-01

2015 marked the 25th anniversary of the commercial use and availability of genetically modified crops. The area of planted biotech crops cultivated globally occupies a cumulative two billion hectares, equivalent to twice the land size of China or the United States. Foods derived from genetically modified plants are widely consumed in many countries and genetically modified soybean protein is extensively used in processed foods throughout the industrialised countries. Genetically modified food technology offers a possible solution to meet current and future challenges in food and medicine. Yet there is a strong undercurrent of anxiety that genetically modified foods are unsafe for human consumption, sometimes fuelled by criticisms based on little or no firm evidence. This has resulted in some countries turning away food destined for famine relief because of the perceived health risks of genetically modified foods. The major concerns include their possible allergenicity and toxicity despite the vigorous testing of genetically modified foods prior to marketing approval. It is imperative that scientists engage the public in a constructive evidence-based dialogue to address these concerns. At the same time, improved validated ways to test the safety of new foods should be developed. A post-launch strategy should be established routinely to allay concerns. Mandatory labelling of genetically modified ingredients should be adopted for the sake of transparency. Such ingredient listing and information facilitate tracing and recall if required.

The movement protein and coat protein of alfalfa mosaic virus accumulate in structurally modified plasmodesmata

NARCIS (Netherlands)

van der Wel, N. N.; Goldbach, R. W.; van Lent, J. W.

1998-01-01

In systemically infected tissues of Nicotiana benthamiana, alfalfa mosaic virus (AMV) coat protein (CP) and movement protein (MP) are detected in plasmodesmata in a layer of three to four cells at the progressing front of infection. Besides the presence of these viral proteins, the plasmodesmata are

Investigation of Chemical and Radiochemical Fingerprints of Water Resources in Siwa Oasis, Western Desert, Egypt

International Nuclear Information System (INIS)

El-Sayed, S.A.; Allam, Kh.A.; Salama, M.H.; El Begawy, H.

2017-01-01

Water resources in Siwa oasis, Egypt; included the Nubian sandstone aquifer system (NSSAS), Tertiary carbonate aquifer system (TCAS) as well as springs and lakes. Existing chemical and radiochemical fingerprints of these resources in the central and western parts of the oasis were examined based on the analyses of 30 water samples collected in 2015. In each sample, the analyzed chemical and radioisotopic constituents were Cl"-, SO_4"2"- , CO_3"2"-, HCO"3 "-, Na"+, K"+, Ca"2"+ and Mg"2"+, Al, B, Ba, Cd, Co, Fe, Cu, Mn, Mo, Ni, Pb, Sr, V, Zn, Si and Cr, "2"2"6 Ra, "2"3"2Th and "4"0K. Other physical properties included ph and TDS were measured in the field. The chemical analysis was carried out following the ASTM methods, while the radiochemical measurements were done using a hyper pure germanium (HPGe) gamma ray spectrometry. Results of this work may be advantage ous to promote the hydrologic database in the oasis, where levels of the natural radioactivity in groundwater resources were established for the first time. Water resources were classified based on their contents of TDS into fresh water for the NSSAS, brackish to salty water for TCAS, brackish water for springs and brine water for lakes. The artesian water of the NSSAS and TCAS and water of the springs were alkaline, while the water of the lakes was acidic. Chemical characters of the ground water of the NSSAS reflected a little response to the processes of water-rock interactions, and the vice versa was observed for the groundwater of the TCAS. The ground water of the NSSAS was dominated by HCO"3"-Na genetic type characterizing the meteoric origin of water. The ground water of the TCAS was characterized by the presence of three genetic types of water (SO"4"-Na, Cl-Mg, and Cl-CA water), indicating the modification of the recharged water from the underlain NSSAS due to the effects of water sediment interactions and mixing with trapped ancient sea water. The chemical properties of spring water were, greatly

Effect of altering local protein fluctuations using artificial intelligence

Directory of Open Access Journals (Sweden)

Katsuhiko Nishiyama

2017-03-01

Full Text Available The fluctuations in Arg111, a significantly fluctuating residue in cathepsin K, were locally regulated by modifying Arg111 to Gly111. The binding properties of 15 dipeptides in the modified protein were analyzed by molecular simulations, and modeled as decision trees using artificial intelligence. The decision tree of the modified protein significantly differed from that of unmodified cathepsin K, and the Arg-to-Gly modification exerted a remarkable effect on the peptide binding properties. By locally regulating the fluctuations of a protein, we may greatly alter the original functions of the protein, enabling novel applications in several fields.

Effect of altering local protein fluctuations using artificial intelligence

Science.gov (United States)

Nishiyama, Katsuhiko

2017-03-01

The fluctuations in Arg111, a significantly fluctuating residue in cathepsin K, were locally regulated by modifying Arg111 to Gly111. The binding properties of 15 dipeptides in the modified protein were analyzed by molecular simulations, and modeled as decision trees using artificial intelligence. The decision tree of the modified protein significantly differed from that of unmodified cathepsin K, and the Arg-to-Gly modification exerted a remarkable effect on the peptide binding properties. By locally regulating the fluctuations of a protein, we may greatly alter the original functions of the protein, enabling novel applications in several fields.

Application of radiochemical method under radioecological situation study in locations of radioactive wastes damping in shallow gulfs of the Novaya Zemlya Archipelago

International Nuclear Information System (INIS)

Stepanets, O.V.; Borisov, A.P.; Komarevskij, V.M.; Ligachev, A.N.; Solov'eva

2005-01-01

Results of works carried out on the 'Boris Petrov Academician' research ship on burial locations examination of submarine potential hazardous objects in the Kara Sea and in the Stepovoj, Abrosimov and Stivol'ka gulfs are cited. Comprehensive radioecological studies in the damping locations of solid radioactive wastes in the Novaya Zemlya Archipelago conducted in 2002-2004 with application of radio-chemical methods for certain radionuclides determination in the samples of bottom sediments and water in the immediate vicinity from the submerged objects are allowing to revealing the objective picture of man-caused contamination of water environment near submerged objects and by the gulfs water area. The studies uniting instrumental tools of acoustic search and visual objects inspection, opportunity of sampling of bottom sediments and near bottom water in the object vicinity and away from it with subsequent analysis of selected samples by the method of direct gamma-spectroscopy and radio-chemical concentration of certain radionuclides are permitting to obtain the statistically assisted data set on special concentrations of cesium, strontium, cobalt, plutonium radionuclides in a water layer and bottom sediments. Obtained results with taking into account of hydrological conditions allow to explain the peculiarities of radioactivity distribution in separate water areas

Radiochemical and Chemical Constituents in Water from Selected Wells and Springs from the Southern Boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman Area, Idaho, 1997

Energy Technology Data Exchange (ETDEWEB)

R. C. Bartholomay (USGS); L. M. Williams (USGS); L. J. Campbell (Idaho Department of Water Resources)

1998-12-01

The U.S. Geological Survey and the Idaho Department of Water Resources, in cooperation with the U.S. Department of Energy, sampled 18 sites as part of the fourth round of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radiochemical and chemical constituents. The samples were collected from seven domestic wells, six irrigation wells, two springs, one dairy well, one observation well, and one stock well. Two quality-assurance samples also were collected and analyzed. None of the radiochemical or chemical constituents exceeded the established maximum contaminant levels for drinking water. Many of the radionuclide- and inorganic-constituent concentrations were greater than their respective reporting levels.

Modification by Ubiquitin-Like Proteins: Significance in Apoptosis and Autophagy Pathways

Directory of Open Access Journals (Sweden)

Monde Ntwasa

2012-09-01

Full Text Available Ubiquitin-like proteins (Ubls confer diverse functions on their target proteins. The modified proteins are involved in various biological processes, including DNA replication, signal transduction, cell cycle control, embryogenesis, cytoskeletal regulation, metabolism, stress response, homeostasis and mRNA processing. Modifiers such as SUMO, ATG12, ISG15, FAT10, URM1, and UFM have been shown to modify proteins thus conferring functions related to programmed cell death, autophagy and regulation of the immune system. Putative modifiers such as Domain With No Name (DWNN have been identified in recent times but not fully characterized. In this review, we focus on cellular processes involving human Ubls and their targets. We review current progress in targeting these modifiers for drug design strategies.

Radiochemical applications of insoluble sulfate columns. Analytical possibilities in the field of the fission product solutions

International Nuclear Information System (INIS)

Barrachina, M.; Sauvagnac, R.

1962-01-01

In this paper we go on with our study of the heterogeneous ion-isotopic exchange in column. At present, we apply it to determine the radiochemical composition of the raw solutions used in the industrial recuperation of the long-lived fission products. The separation of the radioelements contained in these solutions is carried out mainly by making use of small columns, 1-3 cm height, of BaSO 4 or SrSO 4 , under selected experimental conditions. These columns behave like a special type of inorganic exchangers, working by absorption or by ion-isotopic exchange depending on the cases,a nd they provide the means for the selective separation of several important fission products employing very small volumes of fixing and eluting solutions. (Author) 11 refs

Radiochemical separation of {sup 231}Pa from siliceous cake prior to its determination by gamma ray spectrometry

Energy Technology Data Exchange (ETDEWEB)

Dalvi, Aditi A. [Bhabha Atomic Research Centre, Mumbai (India). Analytical Chemistry Div.; Homi Bhabha National Institute, Mumbai (India); Verma, Rakesh

2017-07-01

A simple and fast radiochemical method for the separation of protactinium ({sup 231}Pa) from siliceous cake for its determination by gamma ray spectrometry is described. The method involves (a) a novel approach, the fusion of the siliceous cake with sodium peroxide, (b) the dissolution of the fused mass in nitric acid and (c) the co-precipitation of {sup 231}Pa with manganese dioxide formed in-situ by the addition of solid manganous sulfate and potassium permanganate to the solution. The fusion, effected in a single step, is simpler and highly effective in comparison to methods reported hitherto in literature. The radiochemical yield of {sup 231}Pa, determined using 311.9 keV gamma ray of {sup 233}Pa radiotracer is quantitative (∝90%). The decontamination factors calculated using gamma ray spectrometry and energy dispersive X-ray fluorescence measurements show that the separation from the interfering radionuclides is high whereas separation from major and minor elements is good. Separation by ion-exchange method in hydrochloric acid, hydrofluoric acid and oxalic acid media have comparatively much lower yields. The concentration of {sup 231}Pa in the siliceous cake measured using interference-free 283.6 keV gamma ray was found to be (6.4 ± 0.33) μg kg{sup -1}. The measured concentration of {sup 231}Pa was well above the limit of quantitation whereas the coefficient of variation was ∝5%. The improvement in the limit of detection was due to the reduction in spectral background. Systematic evaluation of various uncertainty parameters showed that the major contributors to the combined uncertainty were efficiency of the high purity germanium detector and the counting statistics. The present sample decomposition and separation methods are robust, simple to perform and can be effectively used for the determination and hence source prospecting of protactinium.

How chelators can modified in vitro and in vivo response of indirect labelled BPTI peptide

International Nuclear Information System (INIS)

Crudo, J.L.; Obenaus, E.R.; Zapata, A.M.; Castiglia, S.G. de

2002-01-01

Aim: the aim of this work was to compare labeling methods for BPTI and in vitro and in vivo properties when it was labeled with 99mTc via two different chelators HYNIC and DTPA. BPTI (provided by Dr. Hnatowich) was used as a model for future labeling of HNE2, an analog peptide used in infection imaging. Materials and Methods: conjugation reaction was carried out at molar ratio of 5:1 between the chelators (NHS-HYNIC and cDTPA) and the peptide BPTI. After Biogel P4 purification, the first four fractions were labeled with 99mTc. The one with the best labelling efficiency was selected for testing each conjugated product. DTPA-BPTI was labeled with 99mTc at pH 5.2. HYNIC-BPTI was labeled with 99mTc using tricine as coligand. 99mTc-DTPA-BPTI was purified by C18 Sep-Pack cartridge due to its impurities. Both 99mTc-labelled BPTI were analysed by reverse phase high performance liquid chromatography (RP-HPLC). Stability of the labeled peptides was asses ed by incubating at 37 0 C with PBS 0.05M pH 7.2, for 24h. 99mTc-peptides were tested for instability toward cysteine, binding to serum protein and trypsin. Bio distributions in normal NIH mice were carried out for both labeled peptides at 2 h post injection (p.i.). Results: Radiochemical purity of 99mTc-((Tricine)HYNIC-BPTI) and 99mTc-DTPA-BPTI determined by RP-HPLC was higher than 95 % and 55 % respectively. The range of specific activity of these products was between 0.07-0.6-MBq/μg. The radiochemical purity of the C18 Sp-Pack purified 99mTc-DTPA-BPTI was 77 %. The dissociation value for 99mTc-((Tricine)HYNIC-BPTI)) was less than 10 % in PBS at 24 h. The results of a cysteine challenge assay of labelled BPTI showed anomalous behaviour for HYNIC conjugate. The activity bound to serum protein of 99mTc-((Tricine)HYNIC-BPTI) was 20 % higher than the value of 99mTc-DTPA-BPTI. G75 radiometric elution profile of 99mTc-((Tricine)HYNIC-BPTI)) : trypsin (Molar ratio 1:10) showed positive binding. Biodistribution in NIH normal mice

Radioiodination of protein using 2,3,5,6-tetrafluorophenyl 3-(nido-carboranyl) propionate (TCP) as a potential bi-functional linker: Synthesis and biodistribution in mice

International Nuclear Information System (INIS)

Lin Rushan; Liu Ning; Yang Yuanyou; Li Bing; Liao Jiali; Jin Jiannan

2009-01-01

2,3,5,6-Tetrafluorophenyl 3-(nido-carboranyl) propionate (TCP), as a new potential bi-functional linker for radiohalogenation of proteins or peptides, was synthesized. With this bi-functional linker, the first attempt to conjugate bovine serum albumin (BSA) with 125 I was made and the biodistribution of the conjugated BSA ( 125 I-TCP-BSA) was investigated in NIH strain mice. By the use of TCP as the linker, BSA was conjugated with 125 I in a labeling yield of 58-75% and with radiochemical purity of 99.8% after purification by Sephadex TM G-50. Even after being kept at room temperature for 72 h, the radiochemical purity of 125 I-TCP-BSA was still more than 98%, much higher than that of the directly 125 I-labeled BSA ( 125 I-BSA). Meanwhile, biodistribution experiments in mice indicated that the uptake of 125 I with 125 I-TCP-BSA into thyroid was obviously less than that with 125 I-BSA post-injection. All the results implied that the 125 I-conjugated BSA ( 125 I-TCP-BSA) was considerably stable in vivo as well as in vitro, and TCP was regarded as a promising bi-functional linker for radiohalogenation of proteins

The effect of selected preparation variables on the radiochemical purity of 99mTc-EDDA-HYNIC-TOC

International Nuclear Information System (INIS)

Betuel Tasdelen

2011-01-01

[ 99m Tc-EDDA-HYNIC-D-Phe 1 , Tyr 3 ]-Ocreotide ( 99m Tc-EDDA-HYNIC-TOC) increasingly emerges to be an alternative tool for somatostatin receptor (SSTR) scintigraphy of neuroendocrine tumours. The high quality of this radiopharmaceutical and its uniformity are very important facts for application of this preparation in clinical practice. Various factors may influence the radiochemical purity (RCP) of certain reagent kits. Some of these include the amount of activity added to the reagent kit, heating time and the age of the formulated kit. The effect of these factors on RCP of 99m Tc-EDDA-HYNIC-TOC has been investigated using high performance liquid chromatography (HPLC) and instant thin layer chromatography (ITLC). (author)

LWR spent-fuel radiochemical measurements and comparison with ORIGEN2 predictions

International Nuclear Information System (INIS)

Blahnik, D.E.; Jenquin, U.P.; Guenther, R.J.

1988-01-01

The Materials Characterization Center (MCC) at Pacific Northwest Laboratory is responsible for providing characterized spent fuel, designated approved testing material (ATMs) for subsequent use in the investigation of nuclear waste disposal forms by the US Department of Energy geologic repository project. The ATMs are selected to assure that test material is available that has a representative range of characteristics important to spent-fuel behavior in a geologic repository. Burnup and fission gas release were the primary criteria for selecting the ATMs. The five spent-fuel ATMs (ATM-101, -103, -104, -105, and -106) currently being characterized by the MCC have rod average burnups ranging from 20 to 43 MWd/kg M, fission gas releases ranging from 0.2 to 11.2%, and are from both boiling water reactors and pressurized water reactors. Radiochemical analyses of the fuel included measurements of 148 Nd (for fuel burnup), the isotopes of uranium and plutonium, and nuclides of importance to repository performance. Cladding samples were analyzed for 14 C. The measured values of selected nuclides were compared with values obtained from calculations with the ORIGEN2 code that was used to predict isotopic quantities for all of the ATMS. Ratios of the ORIGEN2 calculated values to the measured values for ATM-103 and ATM-106 fuel are given

Radiochemical and Chemical Constituents in Water from Selected Wells and Springs from the Southern Boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman Area, Idaho, 1998

Energy Technology Data Exchange (ETDEWEB)

R. C. Bartholomay; B. V. Twining (USGS); L. J. Campbell (Idaho Department of Water Resources)

1999-06-01

The U.S. Geological Survey and the Idaho Department of Water Resources, in cooperation with the U.S. Department of Energy, sampled 18 sites as part of the fourth round of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering and Environmental Laboratory to the Hagerman area. The samples were analyzed for selected radiochemical and chemical constituents. The samples were collected from 2 domestic wells, 12 irrigation wells, 2 stock wells, 1 spring, and 1 public supply well. Two quality-assurance samples also were collected and analyzed. None of the reported radiochemical or chemical constituent concentrations exceeded the established maximum contaminant levels for drinking water. Many of the radionuclide- and inorganic-constituent concentrations were greater than the respective reporting levels. Most of the organic-constituent concentrations were less than the reporting levels.

Radiochemical determination and separation or total radium, 226Ra and 224Ra; Analisis Radioquimico de Radio total, Radio-226 y Radio-224

Energy Technology Data Exchange (ETDEWEB)

Suarez, J A; Gonzalez, J A; Pablo, M A. de

1987-07-01

Radiochemical purification and separation of radium has been carried out and the determination of total radium solubilized in aqueous samples has been studied assuming that all the alpha emitters of the sample have their origin in the 226Ra and elements of its desintegration chain. Also, the activities of 22Ra and 226 Ra have been evaluated separately doing a measurement after the chemical separation of the radium and another one 10 days after. (Author) 9 refs.

Determination of inorganic pyrophosphatase in rat odontoblast layer by a radiochemical method

International Nuclear Information System (INIS)

Granstroem, G.; Linde, A.

1975-01-01

The enzyme inorganic pyrophosphatase (PPsub(i)ase, EC 3.6.1.1) from the odontoblastic layer of rat incisors has been studied by means of a radiochemical micromethod. The enzyme was incubated with 32 P-pyrophosphate in tris-HCl buffer at 37degC. The reaction was linear with time fr at least 45 min, and the pH optimum was found to be 8.8, independent of the amount of pyrophosphate present. Heating the enzyme at 56degC inhibited the enzyme activity rapidly, Mg 2+ ions activated the enzyme by 15 % at an ion concentration of 4 mM, while higher concentrations were inhibitory. Ca 2+ ions and PO 4 3- ions inhibited the enzyme at all concentrations. F - ions did not affect the PPsub(i)ase at concentrations below 8 mM, whereas higher concentrations had an inhibiting effect. Urea was found to inhibit the enzyme at concentrations above 1.5 M, while EDTA was a strong inhibitor at very low concentrations. The characteristics of PPsub(i)ase agree well with the properties of the enzyme nonspecific alkaline phosphatase (EC 3.1.3.1.) studied earlier. (author)

Modified C-reactive protein is expressed by stroke neovessels and is a potent activator of angiogenesis in vitro.

Science.gov (United States)

Slevin, Mark; Matou-Nasri, Sabine; Turu, Marta; Luque, Ana; Rovira, Norma; Badimon, Lina; Boluda, Susana; Potempa, Lawrence; Sanfeliu, Coral; de Vera, Nuria; Krupinski, Jerzy

2010-01-01

Native C-reactive protein (nCRP) is a pentameric oligo-protein and an acute phase reactant whose serum expression is increased in patients with inflammatory disease. We have identified by immunohistochemistry, significant expression of a tissue-binding insoluble modified version or monomeric form of CRP (mCRP) associated with angiogenic microvessels in peri-infarcted regions of patients studied with acute ischaemic stroke. mCRP, but not nCRP was expressed in the cytoplasm and nucleus of damaged neurons. mCRP co-localized with CD105, a marker of angiogenesis in regions of revascularisation. In vitro investigations demonstrated that mCRP was preferentially expressed in human brain microvessel endothelial cells following oxygen-glucose deprivation and mCRP (but not column purified nCRP) associated with the endothelial cell surface, and was angiogenic to vascular endothelial cells, stimulating migration and tube formation in matrigel more strongly than fibroblast growth factor-2. The mechanism of signal transduction was not through the CD16 receptor. Western blotting showed that mCRP stimulated phosphorylation of the key down-stream mitogenic signalling protein ERK1/2. Pharmacological inhibition of ERK1/2 phosphorylation blocked the angiogenic effects of mCRP. We propose that mCRP may contribute to the neovascularization process and because of its abundant presence, be important in modulating angiogenesis in both acute stroke and later during neuro-recovery.

Determination of individual rare earth elements in Vietnamese monazite by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Nguyen Van Suc; Nguyen Mong Sinh

1993-01-01

Radiochemical neutron activation analysis (RNAA) has been applied for determination of rare earth elements (REE) in Vietnamese monazite. The chemical separation procedure used is based on the chromatographic elution of rare earth groups, after the separation of 233 Pa(Th) in irradiated monazite samples by coprecipitation with MnO 2 , the rare earth elements were retained by Biorad AG1 x 8 resin column in 10% 15.4M HNO 3 -90% methanol solution. The elution of heavy rare earth (HREE) and middle rare earth (MREE) groups was carried out with 10% 1M HNO 3 - 90% methanol and 10% 0.05M HNO 3 -90% methanol solution, respectively; while the light rare earths (LREE) were eluted from the column by 0.1M HNO 3 solution. The accuracy of the method was checked by the analysis of granodiorite GSP-I and the rare earth values were in good agreement. (author) 7 refs.; 3 tabs

The Generation of Turnip Crinkle Virus-Like Particles in Plants by the Transient Expression of Wild-Type and Modified Forms of Its Coat Protein.

Science.gov (United States)

Saunders, Keith; Lomonossoff, George P

2015-01-01

Turnip crinkle virus (TCV), a member of the genus carmovirus of the Tombusviridae family, has a genome consisting of a single positive-sense RNA molecule that is encapsidated in an icosahedral particle composed of 180 copies of a single type of coat protein. We have employed the CPMV-HT transient expression system to investigate the formation of TCV-like particles following the expression of the wild-type coat protein or modified forms of it that contain either deletions and/or additions. Transient expression of the coat protein in plants results in the formation of capsid structures that morphologically resemble TCV virions (T = 3 structure) but encapsidate heterogeneous cellular RNAs, rather than the specific TCV coat protein messenger RNA. Expression of an amino-terminal deleted form of the coat protein resulted in the formation of smaller T = 1 structures that are free of RNA. The possibility of utilizing TCV as a carrier for the presentation of foreign proteins on the particle surface was also explored by fusing the sequence of GFP to the C-terminus of the coat protein. The expression of coat protein-GFP hybrids permitted the formation of VLPs but the yield of particles is diminished compared to the yield obtained with unmodified coat protein. Our results confirm the importance of the N-terminus of the coat protein for the encapsidation of RNA and show that the coat protein's exterior P domain plays a key role in particle formation.

Development of production of {sup 99}Mo from LEU target

Energy Technology Data Exchange (ETDEWEB)

Adang, H G; Mutalib, A; Lubis, H [Radioisotope Production Centre, National Atomic Energy Agency, Kawasan Puspiptek, Serpong (Indonesia); and others

1998-10-01

{sup 99}TC, the most popular radioisotope in nuclear medicine, is daughter of {sup 99}Mo. {sup 99}Mo is produced in research reactor by irradiating of high enriched uranium (HEU). However, in recent year, strict regulation that has been implemented by USA DOE and NPT has led to the difficulty in getting HEU. Therefore, BATAN has tried to develop the production of {sup 99}Mo by using low enriched uranium (LEU). The research involves the use of LEU in the production of {sup 99}Mo. This research was started in 1994 by joint-research between BATAN and Argonne National Laboratory USA. This program is divided into three research groups. The first group emphasizes its research on fabrication of LEU foil that is going to be irradiated. The second group studies the irradiation`s aspects and physical characteristic of irradiated LEU foils. The third group studies the radiochemical separation process of fission product {sup 99}Mo from solution of irradiated LEU foils. There are five steps that are carried out in studying of radiochemical separation of {sup 99}Mo from irradiated LEU. First is designing a dissolver that is going to be used in dissolving of LEU foil and testing its reliability. Second is dissolving LEU in the new design dissolver. Third is evaluation the modified of Cintichem`s radiochemical separation process of {sup 99}Mo from LEU. Forth is modifying the Cintichem`s radiochemical separation process of {sup 99}Mo from the solution of irradiated LEU. And fifth is using the modified of Cintichem`s radiochemical separation process for separation {sup 99}Mo from solution of irradiated LEU. The first through the forth steps of experiments were already carried out and will be reported in this workshop, whereas the fifth step of experiment is going to be conducted in February 1998. (author)

Development of Monoclonal Antibodies Recognizing Linear Epitope: Illustration by Three Bacillus thuringiensis Crystal Proteins of Genetically Modified Cotton, Maize, and Tobacco.

Science.gov (United States)

Cao, Zhen; Zhang, Wei; Ning, Xiangxue; Wang, Baomin; Liu, Yunjun; Li, Qing X

2017-11-22

Bacillus thuringiensis Cry1Ac, Cry1Ia1, and Cry1Ie are δ-endotoxin insecticidal proteins widely implemented in genetically modified organisms (GMO), such as cotton, maize, and potato. Western blot assay integrates electrophoresis separation power and antibody high specificity for monitoring specific exogenous proteins expressed in GMO. Procedures for evoking monoclonal antibody (mAb) for Western blot were poorly documented. In the present study, Cry1Ac partially denatured at 100 °C for 5 min was used as an immunogen to develop mAbs selectively recognizing a linear epitope of Cry1Ac for Western blot. mAb 5E9C6 and 3E6E2 selected with sandwich ELISA strongly recognized the heat semidenatured Cry1Ac. Particularly, 3E6E2 recognized both E. coli and cotton seed expressed Cry1Ac in Western blot. Such strategy of using partially denatured proteins as immunogens and using sandwich ELISA for mAb screening was also successfully demonstrated with production of mAbs against Cry1Ie for Western blot assay in maize.

Branched-chain Amino Acid Biosensing Using Fluorescent Modified Engineered Leucine/Isoleucine/Valine Binding Protein

Directory of Open Access Journals (Sweden)

Koji Sode

2007-06-01

Full Text Available A novel fluorescence sensing system for branched-chain amino acids (BCAAswas developed based on engineered leucine/isoleucine/valine-binding proteins (LIVBPsconjugated with environmentally sensitive fluorescence probes. LIVBP was cloned fromEscherichia coli and Gln149Cys, Gly227Cys, and Gln254Cys mutants were generated bygenetic engineering. The mutant LIVBPs were then modified with environmentallysensitive fluorophores. Based on the fluorescence intensity change observed upon thebinding of the ligands, the MIANS-conjugated Gln149Cys mutant (Gln149Cys-M showedthe highest and most sensitive response. The BCAAs Leu, Ile, and Val can each bemonitored at the sub-micromolar level using Gln149Cys-M. Measurements were alsocarried out on a mixture of BCAFAs and revealed that Gln149Cys-M-based measurementis not significantly affected by the change in the molar ratio of Leu, Ile and Val in thesample. Its high sensitivity and group-specific molecular recognition ability make the newsensing system ideally suited for the measurement of BCAAs and the determination of theFischer ratio, an indicator of hepatic disease involving metabolic dysfunction.

Modifying the properties of whey protein isolate edible film by incorporating palm oil and glycerol

Directory of Open Access Journals (Sweden)

Vachiraya Liaotrakoon

2018-02-01

Full Text Available This study aimed to improve the properties of whey protein isolate (WPI films by incorporating palm oil (6, 7, and 8% w/w and glycerol (40, 50 and 60% w/w. The lightness of the films increased as glycerol levels increased, but the redness increased with the increased amount of oil content. Increasing the amounts of palm oil and glycerol improved flexibility (P<0.05, but reduced the strength of the film (P<0.05. Films with higher levels of palm oil and lower amounts of glycerol were less permeable to water vapor and oxygen, but more thermally stable. The size of particles and air bubbles in the films reduced with increased palm oil content, regardless of glycerol level. Among all formulae, the film prepared with 8% palm oil and 40% glycerol showed the best overall results. Modifying WPI films with palm oil and glycerol offers a simple technique for producing packaging with better environmental barrier properties.

Lack of detectable allergenicity in genetically modified maize containing "Cry" proteins as compared to native maize based on in silico & in vitro analysis.

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Chandni Mathur

Full Text Available Genetically modified, (GM crops with potential allergens must be evaluated for safety and endogenous IgE binding pattern compared to native variety, prior to market release.To compare endogenous IgE binding proteins of three GM maize seeds containing Cry 1Ab,1Ac,1C transgenic proteins with non GM maize.An integrated approach of in silico & in vitro methods was employed. Cry proteins were tested for presence of allergen sequence by FASTA in allergen databases. Biochemical assays for maize extracts were performed. Specific IgE (sIgE and Immunoblot using food sensitized patients sera (n = 39 to non GM and GM maize antigens was performed.In silico approaches, confirmed for non sequence similarity of stated transgenic proteins in allergen databases. An insignificant (p> 0.05 variation in protein content between GM and non GM maize was observed. Simulated Gastric Fluid (SGF revealed reduced number of stable protein fractions in GM then non GM maize which might be due to shift of constituent protein expression. Specific IgE values from patients showed insignificant difference in non GM and GM maize extracts. Five maize sensitized cases, recognized same 7 protein fractions of 88-28 kD as IgE bindng in both GM and non-GM maize, signifying absence of variation. Four of the reported IgE binding proteins were also found to be stable by SGF.Cry proteins did not indicate any significant similarity of >35% in allergen databases. Immunoassays also did not identify appreciable differences in endogenous IgE binding in GM and non GM maize.

99mTc-ECD: Comparison of radiochemical purity evaluation techniques

International Nuclear Information System (INIS)

Dumont, A.; De Beco, V.; Ait Ben Ali, S.; Goudou-Sinha, C.; Izembart, M.; Jourdain, J.R.; Lemercier, V.; Linsker, S.; Lours, S.; Moati, F.; Pajard, D.; Piketty, M.L.; Rizzo, N.; Schlageter, M.H.; Moretti, J.L.

1997-01-01

The aim of this study was to validate a testing method for the radiochemical purity (RCP) of the preparations of 99m Tc - ECD that is to be reproducible and easy to realize in services of Nuclear Medicine. After a review of literature, four thin-layer chromatography techniques allowing to evidence the TcO 4 - were evaluated: no.1 - Papier Whatman 31ET / ethyl acetate; no.2 - Papier Whatman 3MM chr / ethyl acetate; no.3 - ITLC Silica gel / ethyl acetate; no.4 - Baker Flex silica gel aluminium oxide IB-F / ethyl acetate (the method proposed by the laboratory). The technique no.1 has presented a bad reproducibility, as well as percentages of RCP very different from those obtained by the other techniques. The techniques no.2 and no.3, although rapid, are characterized by lower reproducibilities in comparison with technique no.4, with, some times, peaks of undetermined nature on the radio-chromatograms no.3. So, in spite of a slower migration (10 min.) the technique no.4 has been selected from the group as the most reliable technique. For this technique, the comparison between the two modes of reading the chromatography (by means of a radio-chromatograph or by measuring the activity of the two halves of the plate by an activity-meter), has shown no significant difference in RCP. Consequently, this method (Baker Flex / ethyl acetate) may by adapted in any service of nuclear medicine, no matter of its equipment

SAAFEC: Predicting the Effect of Single Point Mutations on Protein Folding Free Energy Using a Knowledge-Modified MM/PBSA Approach.

Science.gov (United States)

Getov, Ivan; Petukh, Marharyta; Alexov, Emil

2016-04-07

Folding free energy is an important biophysical characteristic of proteins that reflects the overall stability of the 3D structure of macromolecules. Changes in the amino acid sequence, naturally occurring or made in vitro, may affect the stability of the corresponding protein and thus could be associated with disease. Several approaches that predict the changes of the folding free energy caused by mutations have been proposed, but there is no method that is clearly superior to the others. The optimal goal is not only to accurately predict the folding free energy changes, but also to characterize the structural changes induced by mutations and the physical nature of the predicted folding free energy changes. Here we report a new method to predict the Single Amino Acid Folding free Energy Changes (SAAFEC) based on a knowledge-modified Molecular Mechanics Poisson-Boltzmann (MM/PBSA) approach. The method is comprised of two main components: a MM/PBSA component and a set of knowledge based terms delivered from a statistical study of the biophysical characteristics of proteins. The predictor utilizes a multiple linear regression model with weighted coefficients of various terms optimized against a set of experimental data. The aforementioned approach yields a correlation coefficient of 0.65 when benchmarked against 983 cases from 42 proteins in the ProTherm database. the webserver can be accessed via http://compbio.clemson.edu/SAAFEC/.

Low-level simultaneous determination of As and Sb in standard reference materials using radiochemical neutron activation analysis with isotopic 77As and 125Sb tracers

International Nuclear Information System (INIS)

Byrne, A.R.

1987-01-01

The aim of the present work was to develop an older method used in our laboratory based on selective solvent extraction of As and Sb as their iodides with toluene, and by the use of the radioisotopic tracers 77 As and 125 Sb, to improve the accuracy by better control of the radiochemical yields. 77 As was produced for each sample run by concurrent irradiation of a few mg of GeO 2 followed by a rapid separation of 77 As from 77 Ge. The radiochemically purified sample fraction containing 76+77 As and 122+125 Sb was counted on a Ge detector in good geometry. The γ-lines of the four nuclides do not mutually interfere so that a combined measurement of As and Sb may be made. The method was applied to IAEA Milk Powder A-11, Animal Muscle H-4, Bowen's Kale and some other SRMs. The results obtained are discussed in the light of literature measurements. From present and previous results, together with data by Heydorn, the presently accepted value for As in Bowen's Kale of 140 ngxg -1 may be 20% too high. (orig.)

Radiochemical data obtained by {alpha} spectrometry on unrecrystallized fossil coral samples from the Egyptian shoreline of the north-western Red Sea

Energy Technology Data Exchange (ETDEWEB)

Choukri, A. [Laboratoire de Physique de la Matiere et Rayonnement, Equipe de Physique et Techniques Nucleaires, UFR ' Faibles Radioactivites, Mathematiques physiques et environnement' Universite Ibn Tofail, Faculte des Sciences, Departement de Physique, P.B. 133, 14 000 Kenitra (Morocco)]. E-mail: choukrimajid@yahoo.com; Hakam, O.K. [Laboratoire de Physique de la Matiere et Rayonnement, Equipe de Physique et Techniques Nucleaires, UFR ' Faibles Radioactivites, Mathematiques physiques et environnement' Universite Ibn Tofail, Faculte des Sciences, Departement de Physique, P.B. 133, 14 000 Kenitra (Morocco); Reyss, J.L. [Laboratoire des Sciences de Climat et de l' Environnement, Domaine du CNRS, Avenue de la Terrasse 91 1958, Gif sur Yvette (France); Plaziat, J.C. [Universite de Paris-Sud, Departement des Sciences de la Terre, URA 723, Batiment 504, F-91405 Orsay, Cedex (France)

2007-02-15

In this work, radiochemical results obtained by {alpha} spectrometry on 80 unrecrystallized fossil coral samples from the Egyptian shoreline of the north-western Red Sea are presented and discussed. The coral samples were collected in Egypt from the emerged 5e coral reef terraces over 500km from The Ras Gharib-Ras Shukeir depression (28 deg. 10{sup '}) in the north to Wadi Lahami (north of Ras Banas, 24 deg. 10{sup '}) in the south. The statistical description of radiochemical results (concentrations of U and Th radioisotopes, {sup 234}U/{sup 238}U activity ratios and ages) obtained on a great number of coral samples showed that it is possible to establish methodological criterions which could be used to validate the measured ages before confronting them to the geological context of sampling sites. The obtained results confirm that the unrecrystallized corals ({sup 232}Th<3%) constitute the reliable means of determining the timing of Pleistocene sea-level fluctuations in the past. A few number of measured younger ages could be explain as a result of a rejuvenation due to latter addition of a ''younger'' uranium to the initial stock entered just after coral death. The obvious rejuvenation observed and confirmed is due to a recent cementation of aragonitic deposit on the fossil coral. {sup 238}U varies between 2.2 and 4.9ppm around an average of 3.18+/-0.65ppm. {sup 234}U/ {sup 238}U activity ratios are between 1.08 and 1.28 with an averaged value of 1.164+/-0.016 which exceeds that of present day sea water but which is in agreement with the ratio of 1.16 measured by a precise mass spectrometry in many Pleistocene coral samples. Except three samples dated at least 100ka, the radiochemical age of 5e coral samples vary between 108 and 131ka with an average value of 122.2ka and a standard deviation of 4.3ka. Except for samples from the Zeit area, the reef terrace is between 2 and 6m above the present sea level. This position is similar to

Protein-protein interaction network-based detection of functionally similar proteins within species.

Science.gov (United States)

Song, Baoxing; Wang, Fen; Guo, Yang; Sang, Qing; Liu, Min; Li, Dengyun; Fang, Wei; Zhang, Deli

2012-07-01

Although functionally similar proteins across species have been widely studied, functionally similar proteins within species showing low sequence similarity have not been examined in detail. Identification of these proteins is of significant importance for understanding biological functions, evolution of protein families, progression of co-evolution, and convergent evolution and others which cannot be obtained by detection of functionally similar proteins across species. Here, we explored a method of detecting functionally similar proteins within species based on graph theory. After denoting protein-protein interaction networks using graphs, we split the graphs into subgraphs using the 1-hop method. Proteins with functional similarities in a species were detected using a method of modified shortest path to compare these subgraphs and to find the eligible optimal results. Using seven protein-protein interaction networks and this method, some functionally similar proteins with low sequence similarity that cannot detected by sequence alignment were identified. By analyzing the results, we found that, sometimes, it is difficult to separate homologous from convergent evolution. Evaluation of the performance of our method by gene ontology term overlap showed that the precision of our method was excellent. Copyright © 2012 Wiley Periodicals, Inc.

Radiolabeling of anti-CD20 with Re-188 for treatment of Non-Hodgkin's lymphoma: radiochemical control

International Nuclear Information System (INIS)

Dias, C.R.; Osso Junior, J.A.

2008-01-01

Radioimmunotherapy (RIT) uses target-specific monoclonal antibodies or fragments labeled with a radioactive isotope to combine humoral and radiolytic functions and has the advantage of targeting not only the cell to which the antibody is bound but also the surrounding tumor cells and microenvironment. The most successful clinical studies of RIT in patients with Non-Hodgkin's Lymphoma (NHL) have targeted CD20+ Bcell tumors. Antibody therapy directed against the CD20 antigen on the surface of B-cells is considered one of the first successful target-specific therapies in oncology. The radionuclide rhenium-188 ( 188 Re) is currently produced from the father nuclide 188 W through a transportable generator system. Because of its easy availability and suitable nuclear properties (E βMAX = 2.1 MeV, t1/2 = 16.9 h, E γ = 155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agent and could be conveniently utilized for imaging and dosimetric purposes. The objective of this work is the optimization of direct radiolabeling method of anti-CD20 with 188 Re using a liquid formulation. Anti-CD20 was reduced by incubation with 2-mercaptoethanol at room temperature. The number of resulting free sulphydryl groups was assayed with Ellman's reagent. Optimization of radiolabeling was achieved by varying parameters: antibody mass, reducing agent mass, tartrate mass, stability and reaction time, 188 Re volume and activity. Radiochemical purity of 188 Re-anti-CD20 was evaluated using instant thin layer chromatography-silica gel (ITLC-SG). Quality control methods for evaluation of radiochemical purity showed good labeling yield of the antibody but further studies will be carried out in order to improve the labeling yields and consequently the specific activity of the product. (author)

Chemical and semisynthesis of modified histones.

Science.gov (United States)

Maity, Suman Kumar; Jbara, Muhammad; Brik, Ashraf

2016-05-01

Post-translational modifications (PTMs) of histones play critical roles in the epigenetic regulation of eukaryotic genome by directly altering the biophysical properties of chromatin or by recruiting effector proteins. The large number of PTMs and the inherent complexity in their population and signaling processes make it highly challenging to understand epigenetics-related processes. To address these challenges, accesses to homogeneously modified histones are obligatory. Over the last decade, synthetic protein chemists have been devising novel synthetic tools and applying state-of-the-art chemoselective ligation strategies to prepare precious materials useful in answering fundamental questions in this area. In this short review, we cover some of the recent breakthroughs in these directions in particular the synthesis and semi-synthesis of modified histones and their use to unravel the mysteries of epigenetics. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

Use of composite materials for the determination of Cu, As, Mo, Cd and Sb in biological materials by radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Lucanikova, M.; John, J.; Kucera, J.; Sebesta, F.

2006-01-01

New composite materials were developed and tested for determination of Cu, As, Mo, Cd, and Sb in biological materials by radiochemical neutron activation analysis (RNAA). The materials were prepared by incorporation of solid zinc diethyldithiocarbamate or liquid bis(2,4,4-trimethylpentyl)dithiophosphinic acid (CYANEX 301) into a polyacrylonitrile (PAN) binding matrix. The accuracy of the RNAA procedures was proved by analysis of NIST SRM-1515 Apple Leaves, NIST SRM-1577b Bovine Liver, and NIST SRM-1549 Non Fat Milk Powder. (author)

Effect of Modifying Factors on Radiosensitive Biochemical Reactions

Energy Technology Data Exchange (ETDEWEB)

Romantsev, E. F.; Filippovich, I. V.; Zhulanova, Z. I.; Blokhina, V. D.; Trebenok, Z. A.; Kolesnikov, E. E.; Sheremetyevskaya, T. N.; Nikolsky, A. V.; Zymaleva, O. G. [Institute of Biophysics, USSR Ministry of Health, Moscow, USSR (Russian Federation)

1971-03-15

Some of the radioprotective aminothiols are now routine pharmacopoeial drugs and are used in clinics to decrease the radiation reaction which appears as a side effect during the radiotherapy of cancer. The action of effective modifying agents on radiosensitive biochemical reactions in the organisms of mammals, in principle, cannot be different from the same effects of the protectors on biochemical systems of the human organism. The effect of modifying agents is mediated by biochemical systems. The administration of radioprotective doses of MEA to rats before irradiation results in a significant normalization of the excretion in urine of degradation products of nucleic acids (so-called Dische-positive compounds), the excretion of which sharply rises after irradiation. The curve of the radioprotective effect of MEA (survival rate after administration of radioprotectors at different intervals of time) completely corresponds to curves of the accumulation of MEA which is bound (by mixed disulphide links) to the proteins of liver mitochondria, to proteins of the nuclear-sap, to the hyaloplasm of rat thymus and to the nuclear ribosomes of the spleen. After MEA administration the curve of the biosynthesis of deoxycytidine represents a mirror reflection of the curve of MEA bound to proteins of the thymus hyaloplasm by means of mixed disulphide links. The mechanism of action of such modifying factors as MEA in experiments on mammals is mediated to a great degree through the temporary formation of mixed disulphide links between the aminothiol and the protein component of enzymes in different biochemical systems. (author)

Investigation of the possibility of using hydrogranulation in reprocessing radioactive wastes of radiochemical production facilities

Energy Technology Data Exchange (ETDEWEB)

Revyakin, V.; Borisov, L.M. [All Russian Scientific and Research Institute of Non-Organic Materials, Moscow (Russian Federation)

1996-05-01

Radio-chemical production facilities are constantly accumulating liquid radioactive wastes (still residues as the result of evaporation of extraction and adsorption solutions etc.) which are a complex multicomponent mixtures. The wastes are frequently stored for extended periods of time while awaiting disposition and in some cases, and this is much worse, they are released into the environment. In this report, I would like to draw your attention to some results we have obtained from investigations aimed at simplifying handing of such wastes by the precipitation of hard to dissolve metal hydroxides, the flocculation of the above into granules with the help of surface-active agents (in this case a polyacrylamide - PAA), quickly precipitated and easily filtered. The precipitate may be quickly dried and calcinated, if necessary, and transformed into a dense oxide sinter. In other words it may be transformed into a material convenient for storage or burial.

Receptor activity modifying proteins (RAMPs) interact with the VPAC1 receptor: evidence for differential RAMP modulation of multiple signalling pathways

International Nuclear Information System (INIS)

Christopoulos, G.; Morfis, M.; Sexton, P.M.; Christopoulos, A.; Laburthe, M.; Couvineau, A.

2001-01-01

Full text: Receptor activity modifying proteins (RAMP) constitute a family of three accessory proteins that affect the expression and/or phenotype of the calcitonin receptor (CTR) or CTR-like receptor (CRLR). In this study we screened a range of class II G protein-coupled receptors (PTH1, PTH2, GHRH, VPAC1, VPAC2 receptors) for possible RAMP interactions by measurement of receptor-induced translocation of c-myc tagged RAMP1 or HA tagged RAMP3. Of these, only the VPAC1 receptor caused significant translocation of c-myc-RAMP1 or HA-RAMP3 to the cell surface. Co-transfection of VPAC1 and RAMPs did not alter 125 I-VIP binding and specificity. VPAC1 receptor function was subsequently analyzed through parallel determinations of cAMP accumulation and phosphoinositide (PI) hydrolysis in the presence and absence of each of the three RAMPs. In contrast to CTR-RAMP interaction, where there was an increase in cAMP Pharmacologisand a decrease in PI hydrolysis, VPAC1-RAMP interaction was characterized by a specific increase in agonist-mediated PI hydrolysis when co-transfected with RAMP2. This change was due to an enhancement of Emax with no change in EC 50 value for VIP. No significant change in cAMP accumulation was observed. This is the first demonstration of an interaction of RAMPs with a G protein-coupled receptor outside the CTR family and may suggest a more generalized role for RAMPs in modulating G protein-coupled receptor signaling. Copyright (2001) Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists

Mortality coefficients among personnel of radiochemical plants of open-quotes Mayakclose quotes-Combine for 40-year period of observation

International Nuclear Information System (INIS)

Koshurnikova, N.A.; Komleva, N.S.; Baisogolov, G.D.

1993-01-01

The results of the epidemiological research, conducted among the personnel of the radiochemical plants of open-quotes Mayakclose quotes. Combine are as follows: during the 40-year-period of observation the mortality rate from all and separate causes, except age, is lower, than the expected one, which is calculated on the basis of the National Statistics. Oncological mortality rate is reliably higher, than the expected one, which is conditioned by the high frequency of lung cancer and leucaemia. Internal α-irradiation plays the leading role in the induction of lung cancer, and the increase of mortality rate from leukemia is closely connected with external γ-irradiation

Au nanocrystals grown on a better-defined one-dimensional tobacco mosaic virus coated protein template genetically modified by a hexahistidine tag

International Nuclear Information System (INIS)

Liu Nan; Zhang Wei; Luo Zhaopeng; Zhai Niu; Zhang Hongfei; Li Zhonghao; Jiang Xingyi; Tang Gangling; Hu Qingyuan; Wang Chong; Tian Dandan

2012-01-01

In this paper, tobacco mosaic virus (TMV) coated protein (CP) was genetically modified by introducing a hexahistidine tag into it for a well-defined one-dimensional template, on which Au nanocrystals (NCs) were grown. The results showed that genetic modification could not only ameliorate the one-dimensional structure of the template, but also improve the growth density of Au NCs on the template. This indicated that genetic modification could be an effective method to modulate the structure of the TMVCP template-based nanocomposites allowing for a broader application of them. (paper)

Analysis of radiochemical impurities in radiopharmaceuticals. Pt. 1. A catalogue of methods. Analytik radiochemischer Verunreinigungen in Radiopharmaka. T. 1. Eine Zusammenstellung von Verfahren

Energy Technology Data Exchange (ETDEWEB)

Schuettler, C; Boegl, W

1979-01-01

In a study of the relevant literature analytical methods for the determination of radiochemical purity of pharmaceuticals were compiled in form of a dictionary. It contains data on studies of 71 radiopharmaceuticals and a total of 123 analyses. About half of the substances were labelled with I 131. The most frequently used investigation method was thin-layer chromatography (75 analyses), followed by paper chromatography (36 analyses), electrophoresis (10 analyses) and high-pressure liquid chromatography (2 analyses).

Identification of Atg2 and ArfGAP1 as Candidate Genetic Modifiers of the Eye Pigmentation Phenotype of Adaptor Protein-3 (AP-3) Mutants in Drosophila melanogaster.

Science.gov (United States)

Rodriguez-Fernandez, Imilce A; Dell'Angelica, Esteban C

2015-01-01

The Adaptor Protein (AP)-3 complex is an evolutionary conserved, molecular sorting device that mediates the intracellular trafficking of proteins to lysosomes and related organelles. Genetic defects in AP-3 subunits lead to impaired biogenesis of lysosome-related organelles (LROs) such as mammalian melanosomes and insect eye pigment granules. In this work, we have performed a forward screening for genetic modifiers of AP-3 function in the fruit fly, Drosophila melanogaster. Specifically, we have tested collections of large multi-gene deletions--which together covered most of the autosomal chromosomes-to identify chromosomal regions that, when deleted in single copy, enhanced or ameliorated the eye pigmentation phenotype of two independent AP-3 subunit mutants. Fine-mapping led us to define two non-overlapping, relatively small critical regions within fly chromosome 3. The first critical region included the Atg2 gene, which encodes a conserved protein involved in autophagy. Loss of one functional copy of Atg2 ameliorated the pigmentation defects of mutants in AP-3 subunits as well as in two other genes previously implicated in LRO biogenesis, namely Blos1 and lightoid, and even increased the eye pigment content of wild-type flies. The second critical region included the ArfGAP1 gene, which encodes a conserved GTPase-activating protein with specificity towards GTPases of the Arf family. Loss of a single functional copy of the ArfGAP1 gene ameliorated the pigmentation phenotype of AP-3 mutants but did not to modify the eye pigmentation of wild-type flies or mutants in Blos1 or lightoid. Strikingly, loss of the second functional copy of the gene did not modify the phenotype of AP-3 mutants any further but elicited early lethality in males and abnormal eye morphology when combined with mutations in Blos1 and lightoid, respectively. These results provide genetic evidence for new functional links connecting the machinery for biogenesis of LROs with molecules implicated in

Identification of Atg2 and ArfGAP1 as Candidate Genetic Modifiers of the Eye Pigmentation Phenotype of Adaptor Protein-3 (AP-3 Mutants in Drosophila melanogaster.

Directory of Open Access Journals (Sweden)

Imilce A Rodriguez-Fernandez

Full Text Available The Adaptor Protein (AP-3 complex is an evolutionary conserved, molecular sorting device that mediates the intracellular trafficking of proteins to lysosomes and related organelles. Genetic defects in AP-3 subunits lead to impaired biogenesis of lysosome-related organelles (LROs such as mammalian melanosomes and insect eye pigment granules. In this work, we have performed a forward screening for genetic modifiers of AP-3 function in the fruit fly, Drosophila melanogaster. Specifically, we have tested collections of large multi-gene deletions--which together covered most of the autosomal chromosomes-to identify chromosomal regions that, when deleted in single copy, enhanced or ameliorated the eye pigmentation phenotype of two independent AP-3 subunit mutants. Fine-mapping led us to define two non-overlapping, relatively small critical regions within fly chromosome 3. The first critical region included the Atg2 gene, which encodes a conserved protein involved in autophagy. Loss of one functional copy of Atg2 ameliorated the pigmentation defects of mutants in AP-3 subunits as well as in two other genes previously implicated in LRO biogenesis, namely Blos1 and lightoid, and even increased the eye pigment content of wild-type flies. The second critical region included the ArfGAP1 gene, which encodes a conserved GTPase-activating protein with specificity towards GTPases of the Arf family. Loss of a single functional copy of the ArfGAP1 gene ameliorated the pigmentation phenotype of AP-3 mutants but did not to modify the eye pigmentation of wild-type flies or mutants in Blos1 or lightoid. Strikingly, loss of the second functional copy of the gene did not modify the phenotype of AP-3 mutants any further but elicited early lethality in males and abnormal eye morphology when combined with mutations in Blos1 and lightoid, respectively. These results provide genetic evidence for new functional links connecting the machinery for biogenesis of LROs with

Description of project for pretreatment and storage of wastes of L.P.R. (Radiochemical Processes Laboratory)

International Nuclear Information System (INIS)

Doval, J.C.F.; Mehlich, A.M.; Quilici, D.F.

1987-01-01

The aim of the project is to allow the start up and operation of LPR (Radiochemical Processes Laboratory) as part of the intended activities in the plant. In this paper, the pretreatment and storage of liquid wastes generated at the LPR are described. The pretreatment section will be set up inside the shielded cells already existent in the LPR, where a previous concentration through the evaporation of liquid wastes will take place. The storage section has to be constructed on purpose in order to temporarily store the concentrates. The cells of transference and preconditioning of solid wastes are also described. These cells will be mounted inside the building, allowing the handling of radioactive solids generated as effluents during the reprocessing plan. In the description, the use of non conventional materials for the boiler making and the construction of cells is specially mentioned. (Author)

Synthesis of base-modified 2'-deoxyribonucleoside triphosphates and their use in enzymatic synthesis of modified DNA for applications in bioanalysis and chemical biology.

Science.gov (United States)

Hocek, Michal

2014-11-07

The synthesis of 2'-deoxyribonucleoside triphosphates (dNTPs) either by classical triphosphorylation of nucleosides or by aqueous cross-coupling reactions of halogenated dNTPs is discussed. Different enzymatic methods for synthesis of modified oligonucleotides and DNA by polymerase incorporation of modified nucleotides are summarized, and the applications in redox or fluorescent labeling, as well as in bioconjugations and modulation of interactions of DNA with proteins, are outlined.

Protein adsorption capability on polyurethane and modified-polyurethane membrane for periodontal guided tissue regeneration applications

Energy Technology Data Exchange (ETDEWEB)

Sheikh, Zeeshan [Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Fitzgerald Building, 150 College Street, Toronto, ON M5S 3E2 (Canada); School of Engineering and Materials Science, Queen Mary, University of London, Mile End Rd, London, E1 4NS (United Kingdom); Khan, Abdul Samad, E-mail: draskhan@ciitlahore.edu.pk [Interdisciplinary Research Centre in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Roohpour, Nima [Oral Care R& D, GSK St., Georges Ave., Weybridge KT13 8PA (United Kingdom); Glogauer, Michael [Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Fitzgerald Building, 150 College Street, Toronto, ON M5S 3E2 (Canada); Rehman, Ihtesham u [Department of Materials Science and Engineering, The Kroto Research Institute, North Campus, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom)

2016-11-01

Periodontal disease if left untreated can result in creation of defects within the alveolar ridge. Barrier membranes are frequently used with or without bone replacement graft materials for achieving periodontal guided tissue regeneration (GTR). Surface properties of barrier membranes play a vital role in their functionality and clinical success. In this study polyetherurethane (PEU) membranes were synthesized by using 4,4′-methylene-diphenyl diisocyanate (MDI), polytetramethylene oxide (PTMO) and 1,4-butane diol (BDO) as a chain extender via solution polymerization. Hydroxyl terminated polydimethylsiloxane (PDMS) due to having inherent surface orientation towards air was used for surface modification of PEU on one side of the membranes. This resulting membranes had one surface being PEU and the other being PDMS coated PEU. The prepared membranes were treated with solutions of bovine serum albumin (BSA) in de-ionized water at 37 °C at a pH of 7.2. The surface protein adsorptive potential of PEU membranes was observed using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), Raman spectroscopy and Confocal Raman spectroscopy. The contact angle measurement, tensile strength and modulus of prepared membranes were also evaluated. PEU membrane (89.86 ± 1.62°) exhibited less hydrophobic behavior than PEU-PDMS (105.87 ± 3.16°). The ultimate tensile strength and elastic modulus of PEU (27 ± 1 MPa and 14 ± 2 MPa) and PEU-PDMS (8 ± 1 MPa and 26 ± 1 MPa) membranes was in required range. The spectral analysis revealed adsorption of BSA proteins on the surface of non PDMS coated PEU surface. The PDMS modified PEU membranes demonstrated a lack of BSA adsorption. The non PDMS coated side of the membrane which adsorbs proteins could potentially be used facing towards the defect attracting growth factors for periodontal tissue regeneration. Whereas, the PDMS coated side could serve as an occlusive barrier for preventing gingival epithelial

Protein adsorption capability on polyurethane and modified-polyurethane membrane for periodontal guided tissue regeneration applications

International Nuclear Information System (INIS)

Sheikh, Zeeshan; Khan, Abdul Samad; Roohpour, Nima; Glogauer, Michael; Rehman, Ihtesham u

2016-01-01

Periodontal disease if left untreated can result in creation of defects within the alveolar ridge. Barrier membranes are frequently used with or without bone replacement graft materials for achieving periodontal guided tissue regeneration (GTR). Surface properties of barrier membranes play a vital role in their functionality and clinical success. In this study polyetherurethane (PEU) membranes were synthesized by using 4,4′-methylene-diphenyl diisocyanate (MDI), polytetramethylene oxide (PTMO) and 1,4-butane diol (BDO) as a chain extender via solution polymerization. Hydroxyl terminated polydimethylsiloxane (PDMS) due to having inherent surface orientation towards air was used for surface modification of PEU on one side of the membranes. This resulting membranes had one surface being PEU and the other being PDMS coated PEU. The prepared membranes were treated with solutions of bovine serum albumin (BSA) in de-ionized water at 37 °C at a pH of 7.2. The surface protein adsorptive potential of PEU membranes was observed using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), Raman spectroscopy and Confocal Raman spectroscopy. The contact angle measurement, tensile strength and modulus of prepared membranes were also evaluated. PEU membrane (89.86 ± 1.62°) exhibited less hydrophobic behavior than PEU-PDMS (105.87 ± 3.16°). The ultimate tensile strength and elastic modulus of PEU (27 ± 1 MPa and 14 ± 2 MPa) and PEU-PDMS (8 ± 1 MPa and 26 ± 1 MPa) membranes was in required range. The spectral analysis revealed adsorption of BSA proteins on the surface of non PDMS coated PEU surface. The PDMS modified PEU membranes demonstrated a lack of BSA adsorption. The non PDMS coated side of the membrane which adsorbs proteins could potentially be used facing towards the defect attracting growth factors for periodontal tissue regeneration. Whereas, the PDMS coated side could serve as an occlusive barrier for preventing gingival epithelial

ZZ HATCHES-18, Database for radiochemical modelling

International Nuclear Information System (INIS)

Heath, T.G.

2008-01-01

1 - Description of program or function: HATCHES is a referenced, quality assured, thermodynamic database, developed by Serco Assurance for Nirex. Although originally compiled for use in radiochemical modelling work, HATCHES also includes data suitable for many other applications e.g. toxic waste disposal, effluent treatment and chemical processing. It is used in conjunction with chemical and geochemical computer programs, to simulate a wide variety of reactions in aqueous environments. The database includes thermodynamic data (the log formation constant and the enthalpy of formation for the chemical species) for the actinides, fission products and decay products. The datasets for Ni, Tc, U, Np, Pu and Am are based on the NEA reviews of the chemical thermodynamics of these elements. The data sets for these elements with oxalate, citrate and EDTA are based on the NEA-selected values. For iso-saccharinic acid, additional data (non-selected values) have been included from the NEA review as well as data derived from other sources. HATCHES also includes data for many toxic metals and for elements commonly found in groundwaters or geological materials. HARPHRQ operates by reference to the PHREEQE master species list. Thus the thermodynamic information supplied is: a) the log equilibrium constant for the formation reaction of the requested species from the PHREEQE master species for the corresponding elements; b) the enthalpy of reaction for the formation reaction of the requested species from the PHREEQE master species for the corresponding elements. This version of HATCHES has been updated since the previous release to provide consistency with the selected data from two recent publications in the OECD Nuclear Energy Agency series on chemical thermodynamics: Chemical Thermodynamics Series Volume 7 (2005): Chemical Thermodynamics of Selenium by Aeke Olin (Chairman), Bengt Nolaeng, Lars-Olof Oehman, Evgeniy Osadchii and Erik Rosen and Chemical Thermodynamics Series Volume 8

Cellular responses to modified Plasmodium falciparum MSP119 antigens in individuals previously exposed to natural malaria infection

Directory of Open Access Journals (Sweden)

Awobode Henrietta O

2009-11-01

Full Text Available Abstract Background MSP1 processing-inhibitory antibodies bind to epitopes on the 19 kDa C-terminal region of the Plasmodium falciparum merozoite surface protein 1 (MSP119, inhibiting erythrocyte invasion. Blocking antibodies also bind to this antigen but prevent inhibitory antibodies binding, allowing invasion to proceed. Recombinant MSP119 had been modified previously to allow inhibitory but not blocking antibodies to continue to bind. Immunization with these modified proteins, therefore, has the potential to induce more effective protective antibodies. However, it was unclear whether the modification of MSP119 would affect critical T-cell responses to epitopes in this antigen. Methods The cellular responses to wild-type MSP119 and a panel of modified MSP119 antigens were measured using an in-vitro assay for two groups of individuals: the first were malaria-naïve and the second had been naturally exposed to Plasmodium falciparum infection. The cellular responses to the modified proteins were examined using cells from malaria-exposed infants and adults. Results Interestingly, stimulation indices (SI for responses induced by some of the modified proteins were at least two-fold higher than those elicited by the wild-type MSP119. A protein with four amino acid substitutions (Glu27→Tyr, Leu31→Arg, Tyr34→Ser and Glu43→Leu had the highest stimulation index (SI up to 360 and induced large responses in 64% of the samples that had significant cellular responses to the modified proteins. Conclusion This study suggests that specific MSP119 variants that have been engineered to improve their antigenicity for inhibitory antibodies, retain T-cell epitopes and the ability to induce cellular responses. These proteins are candidates for the development of MSP1-based malaria vaccines.

A review of animal models used to evaluate potential allergenicity of genetically modified organisms (GMOs)

DEFF Research Database (Denmark)

Marsteller, Nathan; Bøgh, Katrine Lindholm; Goodman, Richard E.

2017-01-01

Food safety regulators request prediction of allergenicity for newly expressed proteins in genetically modified (GM) crops and in novel foods. Some have suggested using animal models to assess potential allergenicity. A variety of animal models have been used in research to evaluate sensitisation...... of genetically modified organisms (GMOs).......Food safety regulators request prediction of allergenicity for newly expressed proteins in genetically modified (GM) crops and in novel foods. Some have suggested using animal models to assess potential allergenicity. A variety of animal models have been used in research to evaluate sensitisation...

Translationally controlled tumor protein supplemented chitosan modified glass ionomer cement promotes osteoblast proliferation and function

Energy Technology Data Exchange (ETDEWEB)

Sangsuwan, Jiraporn [Department of Molecular Biology and Bioinformatics, Center for Genomics and Bioinformatics Research, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112 (Thailand); Department of Oral Biology and Occlusion, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla 90112 (Thailand); Wanichpakorn, Supreya; Kedjarune-Leggat, Ureporn [Department of Oral Biology and Occlusion, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla 90112 (Thailand)

2015-09-01

The objective of this study was to evaluate the effect of translationally controlled tumor protein (TCTP) supplemented in a novel glass ionomer cement (BIO-GIC) on normal human osteoblasts (NHost cells). BIO-GIC was a glass ionomer cement (GIC) modified by adding chitosan and albumin to promote the release of TCTP. NHost cells were seeded on specimens of GIC, GIC + TCTP, BIO-GIC and BIO-GIC + TCTP. Cell proliferation was determined by BrdU assay. It was found that BIO-GIC + TCTP had significantly higher proliferation of cells than other specimens. Bone morphogenetic protein-2 (BMP-2) and osteopontin (OPN) gene expressions assessed by quantitative real time PCR and alkaline phosphatase (ALP) activity were used to determine cell differentiation. Bone cell function was investigated by calcium deposition using alizarin assay. Both BMP-2 and OPN gene expressions of cells cultured on specimens with added TCTP increased gradually up-regulation after day 1 and reached the highest on day 3 then down-regulation on day 7. The ALP activity of cells cultured on BIO-GIC + TCTP for 7 days and calcium content after 14 days were significantly higher than other groups. BIO-GIC + TCTP can promote osteoblast cells proliferation, differentiation and function. - Highlights: • Developed a new GIC by supplementing TCTP in BIO-GIC (GIC with chitosan and albumin) • BIO-GIC + TCTP released a higher amount of TCTP than GIC + TCTP. • BIO-GIC + TCTP promoted cell proliferation higher than other specimens and control. • BIO-GIC + TCTP promoted osteoblasts differentiation and function.

Translationally controlled tumor protein supplemented chitosan modified glass ionomer cement promotes osteoblast proliferation and function

International Nuclear Information System (INIS)

Sangsuwan, Jiraporn; Wanichpakorn, Supreya; Kedjarune-Leggat, Ureporn

2015-01-01

The objective of this study was to evaluate the effect of translationally controlled tumor protein (TCTP) supplemented in a novel glass ionomer cement (BIO-GIC) on normal human osteoblasts (NHost cells). BIO-GIC was a glass ionomer cement (GIC) modified by adding chitosan and albumin to promote the release of TCTP. NHost cells were seeded on specimens of GIC, GIC + TCTP, BIO-GIC and BIO-GIC + TCTP. Cell proliferation was determined by BrdU assay. It was found that BIO-GIC + TCTP had significantly higher proliferation of cells than other specimens. Bone morphogenetic protein-2 (BMP-2) and osteopontin (OPN) gene expressions assessed by quantitative real time PCR and alkaline phosphatase (ALP) activity were used to determine cell differentiation. Bone cell function was investigated by calcium deposition using alizarin assay. Both BMP-2 and OPN gene expressions of cells cultured on specimens with added TCTP increased gradually up-regulation after day 1 and reached the highest on day 3 then down-regulation on day 7. The ALP activity of cells cultured on BIO-GIC + TCTP for 7 days and calcium content after 14 days were significantly higher than other groups. BIO-GIC + TCTP can promote osteoblast cells proliferation, differentiation and function. - Highlights: • Developed a new GIC by supplementing TCTP in BIO-GIC (GIC with chitosan and albumin) • BIO-GIC + TCTP released a higher amount of TCTP than GIC + TCTP. • BIO-GIC + TCTP promoted cell proliferation higher than other specimens and control. • BIO-GIC + TCTP promoted osteoblasts differentiation and function

Physicochemical characterization of native and modified sodium caseinate- Vitamin A complexes.

Science.gov (United States)

Gupta, Chitra; Arora, Sumit; Syama, M A; Sharma, Apurva

2018-04-01

Native and modified sodium caseinate- Vitamin A complexes {Sodium caseinate- Vit A complex by stirring (NaCas-VA ST), succinylated sodium caseinate- Vit A complex by stirring (SNaCas-VA ST), reassembled sodium caseinate- Vit A complex (RNaCas-VA) and reassembled succinylated sodium caseinate- Vit A complex (RSNaCas-VA)} were prepared and characterized for their physicochemical characteristics e.g. particle size, zeta potential, turbidity analysis and tryptophan intensities which confirmed structural modification of both native (NaCas-VA ST) and modified (SNaCas-VA ST, RNaCas-VA and RSNaCas- VA) proteins upon complex formation with vitamin A. Binding of vitamin A to milk protein reduced the turbidity caused by vitamin A, however, the particle size and zeta potential of milk protein increased after complexation. Microstructure details of NaCas (spray dried) showed uniform spherical structure, however, other milk proteins and milk protein- Vit A complexes (freeze dried) showed broken glass and flaky structures. Tiny particles were observed on the surface of reassembled protein and reassembled protein- Vit A complexes. Binding of vitamin A to milk protein did not have an influence on the electrophoretic mobility and elution profile (RP-HPLC). Copyright © 2018 Elsevier Ltd. All rights reserved.